WorldWideScience

Sample records for extreme conditions high

  1. Mechanical characterization of alloys in extreme conditions of high strain rates and high temperature

    Science.gov (United States)

    Cadoni, Ezio

    2018-03-01

    The aim of this paper is the description of the mechanical characterization of alloys under extreme conditions of temperature and loading. In fact, in the frame of the Cost Action CA15102 “Solutions for Critical Raw Materials Under Extreme Conditions (CRM-EXTREME)” this aspect is crucial and many industrial applications have to consider the dynamic response of materials. Indeed, for a reduction and substitution of CRMs in alloys is necessary to design the materials and understand if the new materials behave better or if the substitution or reduction badly affect their performance. For this reason, a deep knowledge of the mechanical behaviour at high strain-rates of considered materials is required. In general, machinery manufacturing industry or transport industry as well as energy industry have important dynamic phenomena that are simultaneously affected by extended strain, high strain-rate, damage and pressure, as well as conspicuous temperature gradients. The experimental results in extreme conditions of high strain rate and high temperature of an austenitic stainless steel as well as a high-chromium tempered martensitic reduced activation steel Eurofer97 are presented.

  2. Inelastic X-ray scattering experiments at extreme conditions: high temperatures and high pressures

    Directory of Open Access Journals (Sweden)

    S.Hosokawa

    2008-03-01

    Full Text Available In this article, we review the present status of experimental techniques under extreme conditions of high temperature and high pressure used for inelastic X-ray scattering (IXS experiments of liquid metals, semiconductors, molten salts, molecular liquids, and supercritical water and methanol. For high temperature experiments, some types of single-crystal sapphire cells were designed depending on the temperature of interest and the sample thickness for the X-ray transmission. Single-crystal diamond X-ray windows attached to the externally heated high-pressure vessel were used for the IXS experiment of supercritical water and methanol. Some typical experimental results are also given, and the perspective of IXS technique under extreme conditions is discussed.

  3. Complex Plasma Research Under Extreme Conditions

    International Nuclear Information System (INIS)

    Ishihara, Osamu

    2008-01-01

    Complex plasma research under extreme conditions is described. The extreme conditions include low-dimensionality for self-organized structures of dust particles, dust magnetization in high magnetic field, criticality in phase transition, and cryogenic environment for Coulomb crystals and dust dynamics.

  4. Hygienic diagnosis in extreme conditions

    International Nuclear Information System (INIS)

    Sofronov, G.A.

    1997-01-01

    Review for book by M.P. Zakharchenko, S.A. Lopatin, G.N. Novozhilov, V.I. Zakharov Hygienic diagnosis in extreme conditions is presented discussing the problem of people health preservation under extreme conditions. Hygienic diagnosis is considered illustrated by cases of hostilities (Afghan War), earthquake response in Armenia (1988) and Chernobyl accident response. Attention is paid to the estimation of radiation doses to people and characteristics of main types of dosimeters. The high scientific level of the book is marked

  5. High-energy synchrotron x-ray diffraction studies on disordered materials. From ambient condition to an extreme condition

    International Nuclear Information System (INIS)

    Kohara, Shinji; Ohishi, Yasuo; Suzuya, Kentaro; Takata, Masaki

    2007-01-01

    High-energy x-rays from synchrotron radiation source allow us to measure high-quality diffraction data of the disordered materials from under ambient condition to an extreme condition, which is necessary to reveal the detailed structure of glass, liquid, and amorphous materials. We introduce the high-energy x-ray diffraction beamline and dedicated diffractometer for glass, liquid, and amorphous materials with the recent developments of ancillary equipments. Furthermore our recent studies on the structures of disordered materials reviewed. (author)

  6. Injuries in an Extreme Conditioning Program

    OpenAIRE

    Aune, Kyle T.; Powers, Joseph M.

    2016-01-01

    Background: Extreme conditioning programs (ECPs) are fitness training regimens relying on aerobic, plyometric, and resistance training exercises, often with high levels of intensity for a short duration of time. These programs have grown rapidly in popularity in recent years, but science describing the safety profile of these programs is lacking. Hypothesis: The rate of injury in the extreme conditioning program is greater than the injury rate of weightlifting and the majority of injuries occ...

  7. The extreme condition analyzing for NEMPI shielding of electronic system in high-intensity pulsed radiation diagnosing

    International Nuclear Information System (INIS)

    Cheng Xiaolei; Liu Fang; Ouyang Xiaoping

    2012-01-01

    The difficulty for estimating the NEMPI (electromagnetic pulsed interference caused by the nuclear reaction) on the electronic system in high-intensity pulsed radiation diagnosing is analyzed in this article. To solve the difficulty, a method called 'Extreme Condition Analyzing' is presented for estimating the NEMPI conservatively and reliably. Through an extreme condition hypothesizing which could be described as 'Entire Coupling of Electric Field Energy', the E max (maximum electric field intensity which could be endured by the electronic system in the high-intensity pulsed radiation) could be figured out without any other information of the EMP caused by the nuclear reaction. Then a feasibility inspection is introduced, to confirm that the EMPI shielding request according to E max is not too extreme to be achieved. (authors)

  8. Response of Simple, Model Systems to Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ewing, Rodney C. [Univ. of Michigan, Ann Arbor, MI (United States); Lang, Maik [Univ. of Michigan, Ann Arbor, MI (United States)

    2015-07-30

    The focus of the research was on the application of high-pressure/high-temperature techniques, together with intense energetic ion beams, to the study of the behavior of simple oxide systems (e.g., SiO2, GeO2, CeO2, TiO2, HfO2, SnO2, ZnO and ZrO2) under extreme conditions. These simple stoichiometries provide unique model systems for the analysis of structural responses to pressure up to and above 1 Mbar, temperatures of up to several thousands of kelvin, and the extreme energy density generated by energetic heavy ions (tens of keV/atom). The investigations included systematic studies of radiation- and pressure-induced amorphization of high P-T polymorphs. By studying the response of simple stoichiometries that have multiple structural “outcomes”, we have established the basic knowledge required for the prediction of the response of more complex structures to extreme conditions. We especially focused on the amorphous state and characterized the different non-crystalline structure-types that result from the interplay of radiation and pressure. For such experiments, we made use of recent technological developments, such as the perforated diamond-anvil cell and in situ investigation using synchrotron x-ray sources. We have been particularly interested in using extreme pressures to alter the electronic structure of a solid prior to irradiation. We expected that the effects of modified band structure would be evident in the track structure and morphology, information which is much needed to describe theoretically the fundamental physics of track-formation. Finally, we investigated the behavior of different simple-oxide, composite nanomaterials (e.g., uncoated nanoparticles vs. core/shell systems) under coupled, extreme conditions. This provided insight into surface and boundary effects on phase stability under extreme conditions.

  9. QCD under extreme conditions: an informal discussion

    CERN Document Server

    Fraga, E.S.

    2015-05-22

    We present an informal discussion of some aspects of strong interactions un- der extreme conditions of temperature and density at an elementary level. This summarizes lectures delivered at the 2013 and 2015 CERN – Latin-American Schools of High-Energy Physics and is aimed at students working in experi- mental high-energy physics.

  10. Physics of condensed matter at extreme conditions

    International Nuclear Information System (INIS)

    Ross, M.

    1988-01-01

    The study of matter under extreme conditions is a highly interdisciplinary subject with broad applications to materials science, geophysics and astrophysics. High-pressure properties are studied in the laboratory using static and dynamic techniques. The two differ drastically in the methods of generating and measuring pressure and in the fundamentally different nature of the final compressed state. This article covers a very broad range of conditions, intended to present an overview of important recent developments and to emphasize the behavior of materials and the kinds of properties now being studied

  11. Extreme Conditions Modeling Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    Coe, R. G.; Neary, V. S.; Lawson, M. J.; Yu, Y.; Weber, J.

    2014-07-01

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, NM on May 13th-14th, 2014. The objective of the workshop was to review the current state of knowledge on how to model WECs in extreme conditions (e.g. hurricanes and other large storms) and to suggest how U.S. Department of Energy (DOE) and national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry.

  12. Structural studies of disordered materials using high-energy x-ray diffraction from ambient to extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kohara, Shinji [Japan Synchrotron Radiation Research Institute (SPring-8/JASRI), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Itou, Masayoshi [Japan Synchrotron Radiation Research Institute (SPring-8/JASRI), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Suzuya, Kentaro [Japan Atomic Energy Agency (J-PARC/JAEA), Tokai, Naka, Ibaraki 319-1195 (Japan); Inamura, Yasuhiro [Japan Atomic Energy Agency (J-PARC/JAEA), Tokai, Naka, Ibaraki 319-1195 (Japan); Sakurai, Yoshiharu [Japan Synchrotron Radiation Research Institute (SPring-8/JASRI), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Ohishi, Yasuo [Japan Synchrotron Radiation Research Institute (SPring-8/JASRI), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Takata, Masaki [Japan Synchrotron Radiation Research Institute (SPring-8/JASRI), 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

    2007-12-19

    High-energy x-rays from a synchrotron radiation source allow us to obtain high-quality diffraction data for disordered materials from ambient to extreme conditions, which is necessary for revealing the detailed structures of glass, liquid and amorphous materials. We introduced high-energy x-ray diffraction beamlines and a dedicated diffractometer for glass, liquid and amorphous materials at SPring-8 and report the recent developments of ancillary equipment. Furthermore, the structures of liquid and amorphous materials determined from the high-energy x-ray diffraction data obtained at SPring-8 are discussed.

  13. Foundations of high-energy-density physics physical processes of matter at extreme conditions

    CERN Document Server

    Larsen, Jon

    2017-01-01

    High-energy-density physics explores the dynamics of matter at extreme conditions. This encompasses temperatures and densities far greater than we experience on Earth. It applies to normal stars, exploding stars, active galaxies, and planetary interiors. High-energy-density matter is found on Earth in the explosion of nuclear weapons and in laboratories with high-powered lasers or pulsed-power machines. The physics explored in this book is the basis for large-scale simulation codes needed to interpret experimental results whether from astrophysical observations or laboratory-scale experiments. The key elements of high-energy-density physics covered are gas dynamics, ionization, thermal energy transport, and radiation transfer, intense electromagnetic waves, and their dynamical coupling. Implicit in this is a fundamental understanding of hydrodynamics, plasma physics, atomic physics, quantum mechanics, and electromagnetic theory. Beginning with a summary of the topics and exploring the major ones in depth, thi...

  14. Single-photon detector operating under extremely high background photon flux conditions

    International Nuclear Information System (INIS)

    Prochazka, Ivan; Sopko, Bruno; Blazej, Josef

    2009-01-01

    We are reporting our results in research and development in the field of avalanche semiconductor single-photon detectors and their application. Our goal was a development of a solid-state photon-counting detector capable of high-precision photon arrival time tagging in extremely harsh operating conditions. The background photon flux exceeding 10 9 photons per second hitting the detector active area should not avoid the useful signal detection and recognition on the signal level of units of photons per second. This is background photon flux about two orders of magnitude higher than what the conventional solid-state photon counters accept. The detection timing resolution should be better than 100 ps and the delay stability should be on picosecond level. We have developed and tested the active quenched and gated avalanche structure on silicon providing the required features in connection with the K14 detection chips. The detector is capable of gated operation under the conditions of background photon flux of 5x10 9 photons per second. The operational detector tolerates long term exposures to the input photon flux exceeding 10 15 photons (>1 mW) per second without damage.

  15. Ultrasonic Technique for Density Measurement of Liquids in Extreme Conditions

    Science.gov (United States)

    Kazys, Rymantas; Sliteris, Reimondas; Rekuviene, Regina; Zukauskas, Egidijus; Mazeika, Liudas

    2015-01-01

    An ultrasonic technique, invariant to temperature changes, for a density measurement of different liquids under in situ extreme conditions is presented. The influence of geometry and material parameters of the measurement system (transducer, waveguide, matching layer) on measurement accuracy and reliability is analyzed theoretically along with experimental results. The proposed method is based on measurement of the amplitude of the ultrasonic wave, reflected from the interface of the solid/liquid medium under investigation. In order to enhance sensitivity, the use of a quarter wavelength acoustic matching layer is proposed. Therefore, the sensitivity of the measurement system increases significantly. Density measurements quite often must be performed in extreme conditions at high temperature (up to 220 °C) and high pressure. In this case, metal waveguides between piezoelectric transducer and the measured liquid are used in order to protect the conventional transducer from the influence of high temperature and to avoid depolarization. The presented ultrasonic density measurement technique is suitable for density measurement in different materials, including liquids and polymer melts in extreme conditions. A new calibration algorithm was proposed. The metrological evaluation of the measurement method was performed. The expanded measurement uncertainty Uρ = 7.4 × 10−3 g/cm3 (1%). PMID:26262619

  16. Ultrasonic Technique for Density Measurement of Liquids in Extreme Conditions.

    Science.gov (United States)

    Kazys, Rymantas; Sliteris, Reimondas; Rekuviene, Regina; Zukauskas, Egidijus; Mazeika, Liudas

    2015-08-07

    An ultrasonic technique, invariant to temperature changes, for a density measurement of different liquids under in situ extreme conditions is presented. The influence of geometry and material parameters of the measurement system (transducer, waveguide, matching layer) on measurement accuracy and reliability is analyzed theoretically along with experimental results. The proposed method is based on measurement of the amplitude of the ultrasonic wave, reflected from the interface of the solid/liquid medium under investigation. In order to enhance sensitivity, the use of a quarter wavelength acoustic matching layer is proposed. Therefore, the sensitivity of the measurement system increases significantly. Density measurements quite often must be performed in extreme conditions at high temperature (up to 220 °C) and high pressure. In this case, metal waveguides between piezoelectric transducer and the measured liquid are used in order to protect the conventional transducer from the influence of high temperature and to avoid depolarization. The presented ultrasonic density measurement technique is suitable for density measurement in different materials, including liquids and polymer melts in extreme conditions. A new calibration algorithm was proposed. The metrological evaluation of the measurement method was performed. The expanded measurement uncertainty Uρ = 7.4 × 10(-3) g/cm(3) (1%).

  17. Ultrasonic Technique for Density Measurement of Liquids in Extreme Conditions

    Directory of Open Access Journals (Sweden)

    Rymantas Kazys

    2015-08-01

    Full Text Available An ultrasonic technique, invariant to temperature changes, for a density measurement of different liquids under in situ extreme conditions is presented. The influence of geometry and material parameters of the measurement system (transducer, waveguide, matching layer on measurement accuracy and reliability is analyzed theoretically along with experimental results. The proposed method is based on measurement of the amplitude of the ultrasonic wave, reflected from the interface of the solid/liquid medium under investigation. In order to enhance sensitivity, the use of a quarter wavelength acoustic matching layer is proposed. Therefore, the sensitivity of the measurement system increases significantly. Density measurements quite often must be performed in extreme conditions at high temperature (up to 220 °C and high pressure. In this case, metal waveguides between piezoelectric transducer and the measured liquid are used in order to protect the conventional transducer from the influence of high temperature and to avoid depolarization. The presented ultrasonic density measurement technique is suitable for density measurement in different materials, including liquids and polymer melts in extreme conditions. A new calibration algorithm was proposed. The metrological evaluation of the measurement method was performed. The expanded measurement uncertainty Uρ = 7.4 × 10−3 g/cm3 (1%.

  18. Atomic collisions under extreme conditions in space

    International Nuclear Information System (INIS)

    Itikawa, Yukikazu

    1987-01-01

    In space, atoms and molecules are often placed under the extreme conditions which are very difficult to be realized on Earth. For instance, extremely hot and dense plasmas are found in and around various stellar objects (e.g., neutron stars) on one hand and extremely cold and diffuse gases prevail in interstellar space on the other. There is so strong a magnetic field that electron clouds in atoms and molecules are distorted. The study of atomic collisions under the extreme conditions is not only helpful in understanding the astrophysical environment but also reveals new aspects of the physics of atoms and molecules. This paper is an invitation to the study. (References are not exhaustive but only provide a clue with which more details can be found.) (author)

  19. Extreme Conditions Modeling Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    Coe, Ryan Geoffrey [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Neary, Vincent Sinclair [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Lawon, Michael J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yu, Yi-Hsiang [National Renewable Energy Lab. (NREL), Golden, CO (United States); Weber, Jochem [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-07-01

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, New Mexico on May 13–14, 2014. The objective of the workshop was to review the current state of knowledge on how to numerically and experimentally model WECs in extreme conditions (e.g. large ocean storms) and to suggest how national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry. More than 30 U.S. and European WEC experts from industry, academia, and national research institutes attended the workshop, which consisted of presentations from W EC developers, invited keynote presentations from subject matter experts, breakout sessions, and a final plenary session .

  20. EMA beamline at SIRIUS: extreme condition X-ray methods of analysis

    International Nuclear Information System (INIS)

    Souza Neto, Narcizo

    2016-01-01

    Full text: The EMA beamline (Extreme condition X-ray Methods of Analysis) is one of the hard x-ray undulator beamlines within the first phase of the new synchrotron source in Brazil (Sirius project). This beamline is thought to make a difference where a high brilliance (high flux of up to 2 x 10 14 photons/sec with beam size down to 0.5 x 0.5 μm 2 ) is essential, which is the case for extreme pressures that require small focus and time-resolved that require high photon flux. With that in mind we propose the beamline to have two experimental hutches to cover most of the extreme condition techniques today employed at synchrotron laboratories worldwide. These two stations are thought to provide the general infrastructure for magnets and lasers experiments, which may evolve as new scientific problems appear. In addition to the hutches, support laboratories will be strongly linked and supportive to the experiments at the beamline, covering high pressure instrumentations using diamond anvil cells and pump-and-probe requirements for ultrafast and high power lasers. Along these lines, we will describe the following techniques covered at this beamline: magnetic spectroscopy (XMCD) and scattering (XRMS) under high pressure and very low temperature in order to fully probe both ferromagnetic and antiferromagnetic materials and the dependence with pressure; extreme pressure and temperature XRD and XAS experiments using very small diamond culet anvils and high power lasers. (author)

  1. EMA beamline at SIRIUS: extreme condition X-ray methods of analysis

    Energy Technology Data Exchange (ETDEWEB)

    Souza Neto, Narcizo, E-mail: narcizo.souza@lnls.br [Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil)

    2016-07-01

    Full text: The EMA beamline (Extreme condition X-ray Methods of Analysis) is one of the hard x-ray undulator beamlines within the first phase of the new synchrotron source in Brazil (Sirius project). This beamline is thought to make a difference where a high brilliance (high flux of up to 2 x 10{sup 14} photons/sec with beam size down to 0.5 x 0.5 μm{sup 2}) is essential, which is the case for extreme pressures that require small focus and time-resolved that require high photon flux. With that in mind we propose the beamline to have two experimental hutches to cover most of the extreme condition techniques today employed at synchrotron laboratories worldwide. These two stations are thought to provide the general infrastructure for magnets and lasers experiments, which may evolve as new scientific problems appear. In addition to the hutches, support laboratories will be strongly linked and supportive to the experiments at the beamline, covering high pressure instrumentations using diamond anvil cells and pump-and-probe requirements for ultrafast and high power lasers. Along these lines, we will describe the following techniques covered at this beamline: magnetic spectroscopy (XMCD) and scattering (XRMS) under high pressure and very low temperature in order to fully probe both ferromagnetic and antiferromagnetic materials and the dependence with pressure; extreme pressure and temperature XRD and XAS experiments using very small diamond culet anvils and high power lasers. (author)

  2. Resistance of Microorganisms to Extreme Environmental Conditions and Its Contribution to Astrobiology

    Directory of Open Access Journals (Sweden)

    Pabulo Henrique Rampelotto

    2010-06-01

    Full Text Available In the last decades, substantial changes have occurred regarding what scientists consider the limits of habitable environmental conditions. For every extreme environmental condition investigated, a variety of microorganisms have shown that not only can they tolerate these conditions, but that they also often require these extreme conditions for survival. Microbes can return to life even after hundreds of millions of years. Furthermore, a variety of studies demonstrate that microorganisms can survive under extreme conditions, such as ultracentrifugation, hypervelocity, shock pressure, high temperature variations, vacuums, and different ultraviolet and ionizing radiation intensities, which simulate the conditions that microbes could experience during the ejection from one planet, the journey through space, as well as the impact in another planet. With these discoveries, our knowledge about the biosphere has grown and the putative boundaries of life have expanded. The present work examines the recent discoveries and the principal advances concerning the resistance of microorganisms to extreme environmental conditions, and analyzes its contributions to the development of the main themes of astrobiology: the origins of life, the search for extraterrestrial life, and the dispersion of life in the Universe.

  3. Rational Calibration of Four IEC 61400-1 Extreme External Conditions

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Hansen, Kurt Schaldemose

    2008-01-01

    Based on a set of asymptotic statistical models on closed form this paper presents a rational and consistent calibration of four extreme external conditions defined in the International Electrotechnical Commission (IEC) 61400-1 standard: extreme operating gust, extreme wind shear, extreme coheren...... and proposed specifications of the magnitudes of the extreme external wind conditions are highlighted and discussed using an illustrative example based on two selected terrain types. Copyright © 2008 John Wiley & Sons, Ltd....... gust with direction change and extreme wind direction change. These four extreme external conditions are used in the definition of six of the IEC 61400-1 ultimate load cases. The statistical models are based on simple and easily accessible mean wind speed and turbulence characteristics...

  4. Injuries in an Extreme Conditioning Program.

    Science.gov (United States)

    Aune, Kyle T; Powers, Joseph M

    2016-10-19

    Extreme conditioning programs (ECPs) are fitness training regimens relying on aerobic, plyometric, and resistance training exercises, often with high levels of intensity for a short duration of time. These programs have grown rapidly in popularity in recent years, but science describing the safety profile of these programs is lacking. The rate of injury in the extreme conditioning program is greater than the injury rate of weightlifting and the majority of injuries occur to the shoulder and back. Cross-sectional study. Level 4. This is a retrospective survey of injuries reported by athletes participating in an ECP. An injury survey was sent to 1100 members of Iron Tribe Fitness, a gym franchise with 5 locations across Birmingham, Alabama, that employs exercises consistent with an ECP in this study. An injury was defined as a physical condition resulting from ECP participation that caused the athlete to either seek medical treatment, take time off from exercising, or make modifications to his or her technique to continue. A total of 247 athletes (22%) completed the survey. The majority (57%) of athletes were male (n = 139), and 94% of athletes were white (n = 227). The mean age of athletes was 38.9 years (±8.9 years). Athletes reported participation in the ECP for, on average, 3.6 hours per week (± 1.2 hours). Eighty-five athletes (34%) reported that they had sustained an injury while participating in the ECP. A total of 132 injuries were recorded, yielding an estimated incidence of 2.71 per 1000 hours. The shoulder or upper arm was the most commonly injured body site, accounting for 38 injuries (15% of athletes). Athletes with a previous shoulder injury were 8.1 times as likely to injure their shoulder in the ECP compared with athletes with healthy shoulders. The trunk, back, head, or neck (n = 29, 12%) and the leg or knee (n = 29, 12%) were the second most commonly injured sites. The injury incidence rate among athletes with study estimates the incidence of

  5. Automatic residue removal for high-NA extreme illumination

    Science.gov (United States)

    Moon, James; Nam, Byong-Sub; Jeong, Joo-Hong; Kong, Dong-Ho; Nam, Byung-Ho; Yim, Dong Gyu

    2007-10-01

    An epidemic for smaller node has been that, as the device architecture shrinks, lithography process requires high Numerical Aperture (NA), and extreme illumination system. This, in turn, creates many lithography problems such as low lithography process margin (Depth of Focus, Exposure Latitude), unstable Critical Dimension (CD) uniformity and restricted guideline for device design rule and so on. Especially for high NA, extreme illumination such as immersion illumination systems, above all the related problems, restricted design rule due to forbidden pitch is critical and crucial issue. This forbidden pitch is composed of numerous optical effects but majority of these forbidden pitch compose of photo resist residue and these residue must be removed to relieve some room for already tight design rule. In this study, we propose automated algorithm to remove photo resist residue due to high NA and extreme illumination condition. This algorithm automatically self assembles assist patterns based on the original design layout, therefore insuring the safety and simplicity of the generated assist pattern to the original design and removes any resist residue created by extreme illumination condition. Also we tested our automated algorithm on full chip FLASH memory device and showed the residue removal effect by using commercial verification tools as well as on actual test wafer.

  6. Proceedings of the second symposium on science of hadrons under extreme conditions

    International Nuclear Information System (INIS)

    Chiba, Satoshi

    2000-08-01

    The second symposium on Science of Hadrons under Extreme Conditions, organized by the Research Group for Hadron Science, Advanced Science Research Center, was held at Tokai Research Establishment of JAERI on January 24 to 26, 2000. The symposium was devoted for discussions and presentations of research results in wide variety of fields such as nuclear matter, high-energy nuclear reactions, quantum chromodynamics, supernovae and nucleosynthesis to understand various aspects of hadrons under extreme conditions. The 26 of the presented papers are indexed individually. (J.P.N.)

  7. Shocking matter to extreme conditions

    International Nuclear Information System (INIS)

    Gupta, Y.M.; Sharma, S.M.

    1997-01-01

    A good understanding of the thermodynamic response of matter at high compression and high energy densities is important to several areas of physics. Shock-wave experiments are uniquely suited for obtaining data at extreme conditions, and a shock-compressed matter can be viewed as a condensed system with or without dissociation or as a strongly coupled plasma. This article reviews work by Da Silva et al. in which irradiances ranging from 5x10 superscript 12 to 2x10 superscript 14 W/cm 2 were used to generate 8- to 10-ns square pulses in liquid deuterium. The authors demonstrated negligible pre-heating of the sample, steady propagation of the shock wave, and direct determination of the shock wave velocity along with particle velocity and density in the shocked state. Da Silva et al. results are compared with models and other experimental information, and the usefulness of the data in other areas is assessed. 11 refs., 1 fig

  8. Extreme conditions (p, T, H)

    Energy Technology Data Exchange (ETDEWEB)

    Mesot, J [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    The aim of this paper is to summarize the sample environment which will be accessible at the SINQ. In order to illustrate the type of experiments which will be feasible under extreme conditions of temperature, magnetic field and pressure at the SINQ a few selected examples are also given. (author) 7 figs., 14 refs.

  9. Triticale in the years with extreme weather conditions

    Directory of Open Access Journals (Sweden)

    Nožinić Miloš

    2009-01-01

    Full Text Available Unlike other grain crops, the area under triticale in the Republic of Srpska has been expanding every year. Since the introduction of this plant species in the broad production began a few years ago, the finding of the optimal variety agrotechnique in different environmental conditions has great importance. This paper deals with the results of the trials from seven locations in two very extreme vegetation seasons (2002/03, 2006/07. High yield of triticale on the location Banja Luka (150 m alt. with five triticale varieties in four sowing rates in the replication trial in very unfavorable weather conditions in 2003, points to emphasized triticale tolerance to high temperatures and drought. High grain yield of triticale in the trials on the locations Banja Luka, Butmir (460 m alt. and Živince (230 m alt. was obtained in 2007 too, when all vegetation months had higher mean temperature than long term average, what is a unique appearance in the entire 'meteorological history'. In the paper the appearance of the earliest triticale heading is described and explained. It happened at one production trial on Manjača (250 m alt. in the first decade of March in 2007. On the another location on Manjača (450 m alt., in the macrotrial, rye showed much higher tolerance to extreme soil acidity, than triticale. Obtained results and unusual appearances on triticale are helpful for the further research of the stability and adaptability of more important triticale traits. .

  10. Near-extreme system condition and near-extreme remaining useful time for a group of products

    International Nuclear Information System (INIS)

    Wang, Hai-Kun; Li, Yan-Feng; Huang, Hong-Zhong; Jin, Tongdan

    2017-01-01

    When a group of identical products is operating in field, the aggregation of failures is a catastrophe to engineers and customers who strive to develop reliable and safe products. In order to avoid a swarm of failures in a short time, it is essential to measure the degree of dispersion from different failure times in a group of products to the first failure time. This phenomenon is relevant to the crowding of system conditions near the worst one among a group of products. The group size in this paper represents a finite number of products, instead of infinite number or a single product. We evaluate the reliability of the product fleet from two aspects. First, we define near-extreme system condition and near-extreme failure time for offline solutions, which means no online observations. Second, we apply them to a continuous degradation system that breaks down when it reaches a soft failure threshold. By using particle filtering in the framework of prognostics and health management for a group of products, we aim to estimate near-extreme system condition and further predict the remaining useful life (RUL) using online solutions. Numerical examples are provided to demonstrate the effectiveness of the proposed method. - Highlights: • The aggregation of failures is measured for a group of identical products. • The crowding of failures is quantitated by the near-extreme evaluations. • Near-extreme system condition are given for offline solutions. • Near-extreme remaining useful time are provided for online solutions.

  11. Injuries in an Extreme Conditioning Program

    Science.gov (United States)

    Aune, Kyle T.; Powers, Joseph M.

    2016-01-01

    Background: Extreme conditioning programs (ECPs) are fitness training regimens relying on aerobic, plyometric, and resistance training exercises, often with high levels of intensity for a short duration of time. These programs have grown rapidly in popularity in recent years, but science describing the safety profile of these programs is lacking. Hypothesis: The rate of injury in the extreme conditioning program is greater than the injury rate of weightlifting and the majority of injuries occur to the shoulder and back. Study Design: Cross-sectional study. Level of Evidence: Level 4. Methods: This is a retrospective survey of injuries reported by athletes participating in an ECP. An injury survey was sent to 1100 members of Iron Tribe Fitness, a gym franchise with 5 locations across Birmingham, Alabama, that employs exercises consistent with an ECP in this study. An injury was defined as a physical condition resulting from ECP participation that caused the athlete to either seek medical treatment, take time off from exercising, or make modifications to his or her technique to continue. Results: A total of 247 athletes (22%) completed the survey. The majority (57%) of athletes were male (n = 139), and 94% of athletes were white (n = 227). The mean age of athletes was 38.9 years (±8.9 years). Athletes reported participation in the ECP for, on average, 3.6 hours per week (± 1.2 hours). Eighty-five athletes (34%) reported that they had sustained an injury while participating in the ECP. A total of 132 injuries were recorded, yielding an estimated incidence of 2.71 per 1000 hours. The shoulder or upper arm was the most commonly injured body site, accounting for 38 injuries (15% of athletes). Athletes with a previous shoulder injury were 8.1 times as likely to injure their shoulder in the ECP compared with athletes with healthy shoulders. The trunk, back, head, or neck (n = 29, 12%) and the leg or knee (n = 29, 12%) were the second most commonly injured sites. The

  12. Extreme Transients in the High Energy Universe

    Science.gov (United States)

    Kouveliotou, Chryssa

    2013-01-01

    The High Energy Universe is rich in diverse populations of objects spanning the entire cosmological (time)scale, from our own present-day Milky Way to the re-ionization epoch. Several of these are associated with extreme conditions irreproducible in laboratories on Earth. Their study thus sheds light on the behavior of matter under extreme conditions, such as super-strong magnetic fields (in excess of 10^14 G), high gravitational potentials (e.g., Super Massive Black Holes), very energetic collimated explosions resulting in relativistic jet flows (e.g., Gamma Ray Bursts, exceeding 10^53 ergs). In the last thirty years, my work has been mostly focused on two apparently different but potentially linked populations of such transients: magnetars (highly magnetized neutron stars) and Gamma Ray Bursts (strongly beamed emission from relativistic jets), two populations that constitute unique astrophysical laboratories, while also giving us the tools to probe matter conditions in the Universe to redshifts beyond z=10, when the first stars and galaxies were assembled. I did not make this journey alone I have either led or participated in several international collaborations studying these phenomena in multi-wavelength observations; solitary perfection is not sufficient anymore in the world of High Energy Astrophysics. I will describe this journey, present crucial observational breakthroughs, discuss key results and muse on the future of this field.

  13. Proceedings of the third symposium on science of hadrons under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Satoshi (ed.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-09-01

    The third symposium on Science of Hadrons under Extreme Conditions, organized by the Research Group for Hadron Science, Advanced Science Research Center, was held at Tokai Research Establishment of JAERI on January 29 to 31, 2001. The symposium was devoted for discussions and presentations of research results in wide variety of hadron physics such as nuclear matter, high-energy nuclear reactions, quantum chromodynamics, neutron stars, supernovae, nucleosynthesis as well as finite nuclei to understand various aspects of hadrons under extreme conditions. Twenty two papers on these topics presented at the symposium, including a special talk on the present status of JAERI-KEK joint project on high-intensity proton accelerator, aroused lively discussions among approximately 40 participants. The 20 of the presented papers are indexed individually. (J.P.N.)

  14. What are extreme environmental conditions and how do organisms cope with them?

    Directory of Open Access Journals (Sweden)

    John C. WINGFIELD, J. Patrick KELLEY, Frédéric ANGELIER

    2011-06-01

    Full Text Available Severe environmental conditions affect organisms in two major ways. The environment may be predictably severe such as in deserts, polar and alpine regions, or individuals may be exposed to temporarily extreme conditions through weather, presence of predators, lack of food, social status etc. Existence in an extreme environment may be possible, but then to breed or molt in addition can present major bottlenecks that have resulted in the evolution of hormone-behavior adaptations to cope with unpredictable events. Examples of hormone-behavior adaptations in extreme conditions include attenuated testosterone secretion because territoriality and excess courtship may be too costly when there is one opportunity to reproduce. The individual may even become insensitive to testosterone when target areas of the brain regulating reproductive behavior no longer respond to the hormone. A second example is reduced sensitivity to glucocorticoids following acute stress during the breeding season or molt that allows successful reproduction and/or a vital renewal of the integument to endure extreme conditions during the rest of the year. Reduced sensitivity could involve: (a modulated response of the hypothalamo-pituitary-adrenal axis, (b reduced sensitivity to high glucocorticoid levels, or (c a combination of (a and (b. Moreover, corticosteroid binding proteins (CBP buffer responses to stress by reducing the movement of glucocorticoids into target cells. Finally, intracellular enzymes (11b-hydroxysteroid dehydrogenase and variants can deactivate glucocorticoids entering cells thus reducing interaction with receptors. These mechanisms have important implications for climate change and increasing extremes of weather [Current Zoology 57 (3: 363–374, 2011].

  15. Tolerances of microorganisms to extreme environmental conditions

    International Nuclear Information System (INIS)

    West, J.M.; Arme, S.C.

    1985-03-01

    Microbial isolates from sites relevant to the disposal of radioactive wastes have been subjected to extreme environmental conditions in order to ascertain their tolerance ability. Two groups were chosen, sulphate reducing bacteria and sulphur oxidising bacteria, because of their potential effects on waste containment. They have been subjected to high temperatures, pressures and radiation (delta-emissions) in optimal media conditions and their ability to tolerate the conditions has been ascertained by epifluorescence microscopy and adenosine tri-phosphate (ATP) analysis followed by 'culture-on' to assess post experimental viability. Results indicate that the sulphate reducers in general, are more tolerant to these conditions than the sulphur oxidisers, some proving to be thermophilic. The sulphate reducer showed increased growth rates, as determined by population numbers, at 50 0 C and survived at 80 0 C, 4,500 psig (310 bar) with no subsequent loss in viability. Gamma irradiation of this group and an isolate of 10 5 rad over 4 hours had no effect on population numbers or viability. Such resistances are not apparent with the sulphur oxidisers whose numbers decreased with increasing radiation dose and are destroyed with pressure. (author)

  16. Effects of anthropogenic heat due to air-conditioning systems on an extreme high temperature event in Hong Kong

    Science.gov (United States)

    Wang, Y.; Li, Y.; Di Sabatino, S.; Martilli, A.; Chan, P. W.

    2018-03-01

    Anthropogenic heat flux is the heat generated by human activities in the urban canopy layer, which is considered the main contributor to the urban heat island (UHI). The UHI can in turn increase the use and energy consumption of air-conditioning systems. In this study, two effective methods for water-cooling air-conditioning systems in non-domestic areas, including the direct cooling system and central piped cooling towers (CPCTs), are physically based, parameterized, and implemented in a weather research and forecasting model at the city scale of Hong Kong. An extreme high temperature event (June 23-28, 2016) in the urban areas was examined, and we assessed the effects on the surface thermal environment, the interaction of sea-land breeze circulation and urban heat island circulation, boundary layer dynamics, and a possible reduction of energy consumption. The results showed that both water-cooled air-conditioning systems could reduce the 2 m air temperature by around 0.5 °C-0.8 °C during the daytime, and around 1.5 °C around 7:00-8:00 pm when the planetary boundary layer (PBL) height was confined to a few hundred meters. The CPCT contributed around 80%-90% latent heat flux and significantly increased the water vapor mixing ratio in the atmosphere by around 0.29 g kg-1 on average. The implementation of the two alternative air-conditioning systems could modify the heat and momentum of turbulence, which inhibited the evolution of the PBL height (a reduction of 100-150 m), reduced the vertical mixing, presented lower horizontal wind speed and buoyant production of turbulent kinetic energy, and reduced the strength of sea breeze and UHI circulation, which in turn affected the removal of air pollutants. Moreover, the two alternative air-conditioning systems could significantly reduce the energy consumption by around 30% during extreme high temperature events. The results of this study suggest potential UHI mitigation strategies and can be extended to

  17. Extreme meteorological conditions

    International Nuclear Information System (INIS)

    Altinger de Schwarzkopf, M.L.

    1983-01-01

    Different meteorological variables which may reach significant extreme values, such as the windspeed and, in particular, its occurrence through tornadoes and hurricanes that necesarily incide and wich must be taken into account at the time of nuclear power plants' installation, are analyzed. For this kind of study, it is necessary to determine the basic phenomenum of design. Two criteria are applied to define the basic values of design for extreme meteorological variables. The first one determines the expected extreme value: it is obtained from analyzing the recurence of the phenomenum in a convened period of time, wich may be generally of 50 years. The second one determines the extreme value of low probability, taking into account the nuclear power plant's operating life -f.ex. 25 years- and considering, during said lapse, the occurrence probabilities of extreme meteorological phenomena. The values may be determined either by the deterministic method, which is based on the acknowledgement of the fundamental physical characteristics of the phenomena or by the probabilistic method, that aims to the analysis of historical statistical data. Brief comments are made on the subject in relation to the Argentine Republic area. (R.J.S.) [es

  18. Life under Multiple Extreme Conditions: Diversity and Physiology of the Halophilic Alkalithermophiles

    Science.gov (United States)

    Wiegel, Juergen

    2012-01-01

    Around the world, there are numerous alkaline, hypersaline environments that are heated either geothermally or through intense solar radiation. It was once thought that such harsh environments were inhospitable and incapable of supporting a variety of life. However, numerous culture-dependent and -independent studies revealed the presence of an extensive diversity of aerobic and anaerobic bacteria and archaea that survive and grow under these multiple harsh conditions. This diversity includes the halophilic alkalithermophiles, a novel group of polyextremophiles that require for growth and proliferation the multiple extremes of high salinity, alkaline pH, and elevated temperature. Life under these conditions undoubtedly involves the development of unique physiological characteristics, phenotypic properties, and adaptive mechanisms that enable control of membrane permeability, control of intracellular osmotic balance, and stability of the cell wall, intracellular proteins, and other cellular constituents. This minireview highlights the ecology and growth characteristics of the extremely halophilic alkalithermophiles that have been isolated thus far. Biochemical, metabolic, and physiological properties of the extremely halophilic alkalithermophiles are described, and their roles in resistance to the combined stressors of high salinity, alkaline pH, and high temperature are discussed. The isolation of halophilic alkalithermophiles broadens the physicochemical boundaries for life and extends the boundaries for the combinations of the maximum salinity, pH, and temperature that can support microbial growth. PMID:22492435

  19. In-situ transmission electron microscopy growth of nanoparticles under extreme conditions

    International Nuclear Information System (INIS)

    Luce, F. P.; Azevedo, G. de M.; Baptista, D. L.; Zawislak, F. C.; Oliviero, E.; Fichtner, P. F. P.

    2016-01-01

    The formation and time resolved behavior of individual Pb nanoparticles embedded in silica have been studied by in-situ transmission electron microscopy observations at high temperatures (400–1100 °C) and under 200 keV electron irradiation. It is shown that under such extreme conditions, nanoparticles can migrate at long distances presenting a Brownian-like behavior and eventually coalesce. The particle migration phenomenon is discussed considering the influence of the thermal energy and the electron irradiation effects on the atomic diffusion process which is shown to control particle migration. These results and comparison with ex-situ experiments tackle the stability and the microstructure evolution of nanoparticles systems under extreme conditions. It elucidates on the effects of energetic particle irradiation-annealing treatments either as a tool or as a detrimental issue that could hamper their long-term applications in radiation-harsh environments such as in space or nuclear sectors

  20. Application of Electro Chemical Machining for materials used in extreme conditions

    Science.gov (United States)

    Pandilov, Z.

    2018-03-01

    Electro-Chemical Machining (ECM) is the generic term for a variety of electrochemical processes. ECM is used to machine work pieces from metal and metal alloys irrespective of their hardness, strength or thermal properties, through the anodic dissolution, in aerospace, automotive, construction, medical equipment, micro-systems and power supply industries. The Electro Chemical Machining is extremely suitable for machining of materials used in extreme conditions. General overview of the Electro-Chemical Machining and its application for different materials used in extreme conditions is presented.

  1. Extremely Durable, Flexible Supercapacitors with Greatly Improved Performance at High Temperatures.

    Science.gov (United States)

    Kim, Sung-Kon; Kim, Hae Jin; Lee, Jong-Chan; Braun, Paul V; Park, Ho Seok

    2015-08-25

    The reliability and durability of energy storage devices are as important as their essential characteristics (e.g., energy and power density) for stable power output and long lifespan and thus much more crucial under harsh conditions. However, energy storage under extreme conditions is still a big challenge because of unavoidable performance decays and the inevitable damage of components. Here, we report high-temperature operating, flexible supercapacitors (f-SCs) that can provide reliable power output and extreme durability under severe electrochemical, mechanical, and thermal conditions. The outstanding capacitive features (e.g., ∼40% enhancement of the rate capability and a maximum capacitances of 170 F g(-1) and 18.7 mF cm(-2) at 160 °C) are attributed to facilitated ion transport at elevated temperatures. Under high-temperature operation and/or a flexibility test in both static and dynamic modes at elevated temperatures >100 °C, the f-SCs showed extreme long-term stability of 100000 cycles (>93% of initial capacitance value) and mechanical durability after hundreds of bending cycles (at bend angles of 60-180°). Even at 120 °C, the versatile design of tandem serial and parallel f-SCs was demonstrated to provide both desirable energy and power requirements at high temperatures.

  2. Proceedings of the workshop on scattering experiments under extreme conditions

    International Nuclear Information System (INIS)

    Sakai, N.; Ikeda, H.; Ando, M.

    1991-10-01

    In the National Laboratory for High Energy Physics (KEK), as the research facilities, there are Photon Factory, the facility for utilizing the booster and University of Tokyo Meson Science Research Center. For the research on physical properties, it is very important to do structural analysis in a broad sense and to observe the behavior of quasiparticles in solids. The X-ray and pulsed neutrons required for these researches can be obtained in a single laboratory in KEK, and it is rare in the world. At this opportunity of the workshop on scattering experiments under extreme conditions, it is hoped that the positive interchange between both PF and booster groups will be carried out. The research on magnetic substances using X-ray is a most noteworthy utilization of synchrotron radiation. The discovery of X-ray resonance magnetic scattering by K. Namikawa is one of the remarkable researches using synchrotron radiation in the world. When the extreme conditions around samples are prepared, the quality of signals for the research on physical properties is to be heightened. In this report, the researches on physical properties under ultrahigh pressure and ultralow temperature are reported. (K.I.)

  3. Ecological and biological systems under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zlobin, V S; Nenishkiene, V B

    1989-01-01

    The behaviour of biological and ecological systems under extreme conditions (high and low temperatures, electromagnetic fields of different frequencies, ultraviolet. X-ray and gamma radiation) is analyzed. The ecosystems of macro- and microalgae living in salt, brackinsh and fresh waters are considered in the evolutional aspect basing on their chemical and biochemical composition taking into account the mechanism of radionuclide uptake by water plant cells, osmotic regulation, water and ice structures, combined water in a living organism. The problems of life-support in cosmic flights and of mastering the planets of the Solar system, for instance Mars and Venus, utilizing some microalgae and bacteria with high adaptive properties are discussed. Abnormal water points and their role in the metabolism of a water plant cell are estimated. The 'life niches' are determined at the temperatures exceeding 100 deg C and the possibility of existence for living organisms in high pressure and temperature is grounded. Attempts are made to change the metabolism of the plant and animal cell by subjecting it to the action of electromagnetic and thermal fields, heavy water, chemical and pharmocological substances changing the structure of bound water. 333 refs.; 79 tabs.

  4. Life at extreme conditions: neutron scattering studies of biological molecules suggest that evolution selected dynamics

    International Nuclear Information System (INIS)

    Zaccai, Joseph Giuseppe

    2008-01-01

    The short review concentrates on recent work performed at the neutrons in biology laboratories of the Institut Laue Langevin and Institut de Biologie Structurale in Grenoble. Extremophile organisms have been discovered that require extreme conditions of temperature, pressure or solvent environment for survival. The existence of such organisms poses a significant challenge in understanding the physical chemistry of their proteins, in view of the great sensitivity of protein structure and stability to the aqueous environment and to external conditions in general. Results of neutron scattering measurements on the dynamics of proteins from extremophile organisms, in vitro as well as in vivo, indicated remarkably how adaptation to extreme conditions involves forces and fluctuation amplitudes that have been selected specifically, suggesting that evolutionary macromolecular selection proceeded via dynamics. The experiments were performed on a halophilic protein, and membrane adapted to high salt, a thermophilic enzyme adapted to high temperature and its mesophilic (adapted to 37 degC) homologue; and in vivo for psychrophilic, mesophilic, thermophilic and hyperthermophilic bacteria, adapted respectively to temperatures of 4 degC, 37 degC, 75 degC and 85 degC. Further work demonstrated the existence of a water component of exceptionally low mobility in an extreme halophile from the Dead Sea, which is not present in mesophile bacterial cells. (author)

  5. Molecular Mechanisms of Survival Strategies in Extreme Conditions

    Directory of Open Access Journals (Sweden)

    Federica Migliardo

    2012-12-01

    Full Text Available Today, one of the major challenges in biophysics is to disclose the molecular mechanisms underlying biological processes. In such a frame, the understanding of the survival strategies in extreme conditions received a lot of attention both from the scientific and applicative points of view. Since nature provides precious suggestions to be applied for improving the quality of life, extremophiles are considered as useful model-systems. The main goal of this review is to present an overview of some systems, with a particular emphasis on trehalose playing a key role in several extremophile organisms. The attention is focused on the relation among the structural and dynamic properties of biomolecules and bioprotective mechanisms, as investigated by complementary spectroscopic techniques at low- and high-temperature values.

  6. Experimental and theoretical study of electronic structure of aluminum in extreme conditions with X-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Festa, Floriane

    2013-01-01

    Matter in extreme conditions belongs to Warm Dense Matter regime which lays between dense plasma regime and condensed matter. This regime is still not well known, indeed it is very complex to generate such plasma in the laboratory to get experimental data and validate models. The goal of this thesis is to study electronic structure of aluminum in extreme conditions with X-ray absorption spectroscopy. Experimentally aluminum has reached high densities and high temperatures, up to now unexplored. An X-ray source has also been generated to probe highly compressed aluminum. Two spectrometers have recorded aluminum absorption spectra and aluminum density and temperature conditions have been deduced thanks to optical diagnostics. Experimental spectra have been compared to ab initio spectra, calculated in the same conditions. The theoretical goal was to validate the calculation method in high densities and high temperatures regime with the study of K-edge absorption modifications. We also used absorption spectra to study the metal-non metal transition which takes place at low density (density ≤ solid density). This transition could be study with electronic structure modifications of the system. (author) [fr

  7. User-Defined Meteorological (MET) Profiles from Climatological and Extreme Condition Data

    Science.gov (United States)

    2018-04-01

    ARL-TN-0876 ● MAR 2018 US Army Research Laboratory User-Defined Meteorological (MET) Profiles from Climatological and Extreme...needed. Do not return it to the originator. ARL-TN-0876 ● MAR 2018 US Army Research Laboratory User-Defined Meteorological (MET...User-Defined Meteorological (MET) Profiles from Climatological and Extreme Condition Data 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

  8. Establishment and performance of an experimental green roof under extreme climatic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Petra M., E-mail: pkklein@ou.edu [School of Meteorology, University of Oklahoma, Norman, OK (United States); Coffman, Reid, E-mail: rcoffma4@kent.edu [College of Architecture and Environmental Design, Kent State University, Kent, OH (United States)

    2015-04-15

    Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April–October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating

  9. Establishment and performance of an experimental green roof under extreme climatic conditions

    International Nuclear Information System (INIS)

    Klein, Petra M.; Coffman, Reid

    2015-01-01

    Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April–October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating

  10. Extreme groundwater levels caused by extreme weather conditions - the highest ever measured groundwater levels in Middle Germany and their management

    Science.gov (United States)

    Reinstorf, F.; Kramer, S.; Koch, T.; Pfützner, B.

    2017-12-01

    Extreme weather conditions during the years 2009 - 2011 in combination with changes in the regional water management led to maximum groundwater levels in large areas of Germany in 2011. This resulted in extensive water logging, with problems especially in urban areas near rivers, where water logging produced huge problems for buildings and infrastructure. The acute situation still exists in many areas and requires the development of solution concepts. Taken the example of the Elbe-Saale-Region in the Federal State of Saxony-Anhalt, were a pilot research project was carried out, the analytical situation, the development of a management tool and the implementation of a groundwater management concept are shown. The central tool is a coupled water budget - groundwater flow model. In combination with sophisticated multi-scale parameter estimation, a high-resolution groundwater level simulation was carried out. A decision support process with an intensive stakeholder interaction combined with high-resolution simulations enables the development of a management concept for extreme groundwater situations in consideration of sustainable and environmentally sound solutions mainly on the base of passive measures.

  11. Behavior under Extreme Conditions: The Titanic Disaster

    OpenAIRE

    Bruno S. Frey; David A. Savage; Benno Torgler

    2011-01-01

    During the night of April 14, 1912, the RMS Titanic collided with an iceberg on her maiden voyage. Two hours and 40 minutes later she sank, resulting in the loss of 1,501 lives—more than two-thirds of her 2,207 passengers and crew. This remains one of the deadliest peacetime maritime disasters in history and by far the most famous. For social scientists, evidence about how people behaved as the Titanic sunk offers a quasi-natural field experiment to explore behavior under extreme conditions o...

  12. Solidification at the High and Low Rate Extreme

    Energy Technology Data Exchange (ETDEWEB)

    Meco, Halim [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

  13. Distribution patterns of terricolous and saxicolous lichens in extreme desert conditions

    Science.gov (United States)

    Temina, M.

    2012-04-01

    The investigation of biodiversity in stressful habitats is of great interest because it elucidates relationships between organisms and their environment, as well as revealing the mechanisms of their survival and adaptation to extreme conditions. Deserts represent such stressful habitats where harsh climate and limited resources greatly influence the formation of biota. In order to understand the link between microscale environmental variability in extreme arid conditions and lichen biodiversity patterns, we conducted the present study. For this purpose, the structure and distribution of lichen communities on soil and cobbles at six stations at "Evolution Canyon" III (EC III), Nahal Shaharut, in the extreme southern Negev, Israel, were examined. The opposite slopes of the canyon represented specific ecological niches characterized by sharply different microclimatic conditions. The following characteristics of lichen communities were studied: species richness, systematic diversity, biogeographical elements, frequencies and distribution of species, their morphological and anatomical characteristics, reproductive strategy, and ecological peculiarities. In the research site three environmental variables were evaluated: soil moisture, and temperatures of soil and cobbles. The Canonical Correspondence Analysis was used to study the influence of these ecological variables on the distribution of lichen species. The lichen diversity of EC III was very poor and comprised 12 species (3 cyanoliches on soil vs. 9 phycolichens on cobbles). Most of them belong to a specific group of arid endemic elements, adapted to survive in extreme arid conditions in the deserts of the Levant. The harsh desert conditions of the canyon negatively influence the reproductive ability of lichens. This influence is expressed in the decreased sizes of fruit bodies in some species, and the frequent occurrence of sterile specimens among lichens found in the canyon. A comparative analysis of structure

  14. Proceedings of the first symposium on science of hadrons under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Satoshi; Maruyama, Toshiki [eds.

    1999-08-01

    The first symposium on Science of Hadrons under Extreme Conditions, organized by the Research Group for Hadron Science, Advanced Science Research Center, was held at Tokai Research Establishment of JAERI on March 11 and 12, 1999. The symposium was devoted for discussions and presentations of research results in wide variety of fields such as observation of X-ray pulsars, theoretical studies of nuclear matter, nuclear structure, low- and high-energy nuclear reactions and QCD. Thirty seven papers on these topics presented at the symposium are indexed individually. (J.P.N.)

  15. High resolution modelling of extreme precipitation events in urban areas

    Science.gov (United States)

    Siemerink, Martijn; Volp, Nicolette; Schuurmans, Wytze; Deckers, Dave

    2015-04-01

    The present day society needs to adjust to the effects of climate change. More extreme weather conditions are expected, which can lead to longer periods of drought, but also to more extreme precipitation events. Urban water systems are not designed for such extreme events. Most sewer systems are not able to drain the excessive storm water, causing urban flooding. This leads to high economic damage. In order to take appropriate measures against extreme urban storms, detailed knowledge about the behaviour of the urban water system above and below the streets is required. To investigate the behaviour of urban water systems during extreme precipitation events new assessment tools are necessary. These tools should provide a detailed and integral description of the flow in the full domain of overland runoff, sewer flow, surface water flow and groundwater flow. We developed a new assessment tool, called 3Di, which provides detailed insight in the urban water system. This tool is based on a new numerical methodology that can accurately deal with the interaction between overland runoff, sewer flow and surface water flow. A one-dimensional model for the sewer system and open channel flow is fully coupled to a two-dimensional depth-averaged model that simulates the overland flow. The tool uses a subgrid-based approach in order to take high resolution information of the sewer system and of the terrain into account [1, 2]. The combination of using the high resolution information and the subgrid based approach results in an accurate and efficient modelling tool. It is now possible to simulate entire urban water systems using extreme high resolution (0.5m x 0.5m) terrain data in combination with a detailed sewer and surface water network representation. The new tool has been tested in several Dutch cities, such as Rotterdam, Amsterdam and The Hague. We will present the results of an extreme precipitation event in the city of Schiedam (The Netherlands). This city deals with

  16. Quantitative evaluation of the mitochondrial proteomes of Drosophila melanogaster adapted to extreme oxygen conditions.

    Directory of Open Access Journals (Sweden)

    Songyue Yin

    Full Text Available Mitochondria are the primary organelles that consume oxygen and provide energy for cellular activities. To investigate the mitochondrial mechanisms underlying adaptation to extreme oxygen conditions, we generated Drosophila strains that could survive in low- or high-oxygen environments (LOF or HOF, respectively, examined their mitochondria at the ultrastructural level via transmission electron microscopy, studied the activity of their respiratory chain complexes, and quantitatively analyzed the protein abundance responses of the mitochondrial proteomes using Isobaric tag for relative and absolute quantitation (iTRAQ. A total of 718 proteins were identified with high confidence, and 55 and 75 mitochondrial proteins displayed significant differences in abundance in LOF and HOF, respectively, compared with the control flies. Importantly, these differentially expressed mitochondrial proteins are primarily involved in respiration, calcium regulation, the oxidative response, and mitochondrial protein translation. A correlation analysis of the changes in the levels of the mRNAs corresponding to differentially regulated mitochondrial proteins revealed two sets of proteins with different modes of regulation (transcriptional vs. post-transcriptional in both LOF and HOF. We believe that these findings will not only enhance our understanding of the mechanisms underlying adaptation to extreme oxygen conditions in Drosophila but also provide a clue in studying human disease induced by altered oxygen tension in tissues and cells.

  17. Diamonds on Diamond: structural studies at extreme conditions on the Diamond Light Source.

    Science.gov (United States)

    McMahon, M I

    2015-03-06

    Extreme conditions (EC) research investigates how the structures and physical and chemical properties of materials change when subjected to extremes of pressure and temperature. Pressures in excess of one million times atmospheric pressure can be achieved using a diamond anvil cell, and, in combination with high-energy, micro-focused radiation from a third-generation synchrotron such as Diamond, detailed structural information can be obtained using either powder or single-crystal diffraction techniques. Here, I summarize some of the research drivers behind international EC research, and then briefly describe the techniques by which high-quality diffraction data are obtained. I then highlight the breadth of EC research possible on Diamond by summarizing four examples from work conducted on the I15 and I19 beamlines, including a study which resulted in the first research paper from Diamond. Finally, I look to the future, and speculate as to the type of EC research might be conducted at Diamond over the next 10 years. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  18. A new fluorescent pH probe for extremely acidic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yu [School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Taishan College, Shandong University, Jinan 250100 (China); Jiang, Zheng [School of Life Science, Shandong University, Jinan 250100 (China); Taishan College, Shandong University, Jinan 250100 (China); Xiao, Yu [School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Taishan College, Shandong University, Jinan 250100 (China); Bi, Fu-Zhen [School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Miao, Jun-Ying, E-mail: miaojy@sdu.edu.cn [School of Life Science, Shandong University, Jinan 250100 (China); Zhao, Bao-Xiang, E-mail: bxzhao@sdu.edu.cn [School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2014-04-01

    A new coumarin-based fluorescent probe can detect highly acidic conditions in both solution and bacteria with high selectivity and sensitivity. Highlights: • A new fluorescence probe for very low pH was synthesized and characterized. • The probe can monitor pH in solution and bacteria. • The two-step protonation of N atoms of the probe leads to fluorescence quenching. Abstract: A novel turn-off fluorescent probe based on coumarin and imidazole moiety for extremely acidic conditions was designed and developed. The probe with pKa = 2.1 is able to respond to very low pH value (below 3.5) with high sensitivity relying on fluorescence quenching at 460 nm in fluorescence spectra or the ratios of absorbance maximum at 380 nm to that at 450 nm in UV–vis spectra. It can quantitatively detect pH value based on equilibrium equation, pH = pKa -log[(Ix - Ib)/(Ia - Ix)]. It had very short response time that was less than 1 min, good reversibility and nearly no interference from common metal ions. Moreover, using ¹H NMR analysis and theoretical calculation of molecular orbital, we verified that a two-step protonation process of two N atoms of the probe leaded to photoinduced electron transfer (PET), which was actually the mechanism of the fluorescence quenching phenomenon under strongly acidic conditions. Furthermore, the probe was also applied to imaging strong acidity in bacteria, E.coli and had good effect. This work illustrates that the new probe could be a practical and ideal pH indicator for strongly acidic conditions with good biological significance.

  19. Extreme conditions over Europe and North America: role of the Atlantic Multidecadal Variability

    Science.gov (United States)

    Ruprich-Robert, Yohan; Msadek, Rym; Delworth, Tom

    2016-04-01

    The Atlantic Multidecadal Variability (AMV) is the result and possibly the source of marked modulations of the climate over many areas of the globe. For instance, the relatively warm and dry climate of North America throughout the 30-yr interval of 1931-60, during which the Dust Bowl and the 1950's drought occurred, has been linked to the concomitant warm phase of the AMV. During this period relative warm and wet conditions prevailed over Europe. After 1960, the Atlantic began to cool, and for almost three decades the North American climate turned wetter and cooler whereas Europe experienced cooler and dryer conditions. However, the shortness of the historical observations compared to the AMV period suggested by longer proxy (~60-80yr) does not allow to firmly conclude on the causal effect of the AMV. We use a model approach to isolate the causal role of the AMV on the occurrence of extreme events over Europe and North America. We present experiments based on two GFDL global climate models, a low resolution version, CM2.1 and a higher resolution model for the atmospheric component, FLOR. In both model experiments sea surface temperatures in the North Atlantic sector are restored to the observed AMV pattern, while the other basins are left fully coupled. In order to explore and robustly isolate the AMV impacts on extreme events, we use large ensemble simulations (100 members for CM2.1 and 50 for FLOR) that we run for 20 years. We find that a positive phase of the AMV increases the frequency of occurrence of drought over North America and of extremely cold/warm conditions over Northern/Central Europe during winter/summer. Interestingly, we find that the AMV impacts on these extreme conditions are modulated by the Pacific response to the AMV itself. Members that develop a weak Pacific response show more extreme events over Europe whereas those that develop a strong Pacific response show more extreme events over North America.

  20. Studies in the statistical and thermal properties of hadronic matter under some extreme conditions

    International Nuclear Information System (INIS)

    Chase, K.C.; Mekjian, A.Z.; Bhattacharyya, P.

    1997-01-01

    The thermal and statistical properties of hadronic matter under some extreme conditions are investigated using an exactly solvable canonical ensemble model. A unified model describing both the fragmentation of nuclei and the thermal properties of hadronic matter is developed. Simple expressions are obtained for quantities such as the hadronic equation of state, specific heat, compressibility, entropy, and excitation energy as a function of temperature and density. These expressions encompass the fermionic aspect of nucleons, such as degeneracy pressure and Fermi energy at low temperatures and the ideal gas laws at high temperatures and low density. Expressions are developed which connect these two extremes with behavior that resembles an ideal Bose gas with its associated Bose condensation. In the thermodynamic limit, an infinite cluster exists below a certain critical condition in a manner similar to the sudden appearance of the infinite cluster in percolation theory. The importance of multiplicity fluctuations is discussed and some recent data from the EOS collaboration on critical point behavior of nuclei can be accounted for using simple expressions obtained from the model. copyright 1997 The American Physical Society

  1. Wireless pilot monitoring system for extreme race conditions.

    Science.gov (United States)

    Pino, Esteban J; Arias, Diego E; Aqueveque, Pablo; Melin, Pedro; Curtis, Dorothy W

    2012-01-01

    This paper presents the design and implementation of an assistive device to monitor car drivers under extreme conditions. In particular, this system is designed in preparation for the 2012 Atacama Solar Challenge to be held in the Chilean desert. Actual preliminary results show the feasibility of such a project including physiological and ambient sensors, real-time processing algorithms, wireless data transmission and a remote monitoring station. Implementation details and field results are shown along with a discussion of the main problems found in real-life telemetry monitoring.

  2. Extreme Sea Conditions in Shallow Water: Estimation based on in-situ measurements

    Science.gov (United States)

    Le Crom, Izan; Saulnier, Jean-Baptiste

    2013-04-01

    The design of marine renewable energy devices and components is based, among others, on the assessment of the environmental extreme conditions (winds, currents, waves, and water level) that must be combined together in order to evaluate the maximal loads on a floating/fixed structure, and on the anchoring system over a determined return period. Measuring devices are generally deployed at sea over relatively short durations (a few months to a few years), typically when describing water free surface elevation, and extrapolation methods based on hindcast data (and therefore on wave simulation models) have to be used. How to combine, in a realistic way, the action of the different loads (winds and waves for instance) and which correlation of return periods should be used are highly topical issues. However, the assessment of the extreme condition itself remains a not-fully-solved, crucial, and sensitive task. Above all in shallow water, extreme wave height, Hmax, is the most significant contribution in the dimensioning process of EMR devices. As a case study, existing methodologies for deep water have been applied to SEMREV, the French marine energy test site. The interest of this study, especially at this location, goes beyond the simple application to SEMREV's WEC and floating wind turbines deployment as it could also be extended to the Banc de Guérande offshore wind farm that are planned close by. More generally to pipes and communication cables as it is a redundant problematic. The paper will first present the existing measurements (wave and wind on site), the prediction chain that has been developed via wave models, the extrapolation methods applied to hindcast data, and will try to formulate recommendations for improving this assessment in shallow water.

  3. Assessing the importance of spatio-temporal RCM resolution when estimating sub-daily extreme precipitation under current and future climate conditions

    DEFF Research Database (Denmark)

    Sunyer Pinya, Maria Antonia; Luchner, J.; Onof, C.

    2017-01-01

    extreme precipitation over Denmark generated by the regional climate model (RCM) HIRHAM-ECEARTH at different spatial resolutions (8, 12, 25 and 50km), three RCM from the RiskChange project at 8km resolution and three RCMs from ENSEMBLES at 25km resolution at temporal aggregations from 1 to 48h...... are more skewed than the observational dataset, which leads to an overestimation by the higher spatial resolution simulations. Nevertheless, in general, under current conditions RCM simulations at high spatial resolution represent extreme events and high-order moments better. The changes projected...

  4. Extreme states of matter high energy density physics

    CERN Document Server

    Fortov, Vladimir E

    2016-01-01

    With its many beautiful colour pictures, this book gives fascinating insights into the unusual forms and behaviour of matter under extremely high pressures and temperatures. These extreme states are generated, among other things, by strong shock, detonation and electric explosion waves, dense laser beams,electron and ion beams, hypersonic entry of spacecraft into dense atmospheres of planets, and in many other situations characterized by extremely high pressures and temperatures.Written by one of the world's foremost experts on the topic, this book will inform and fascinate all scientists dealing with materials properties and physics, and also serve as an excellent introduction to plasma-, shock-wave and high-energy-density physics for students and newcomers seeking an overview. This second edition is thoroughly revised and expanded, in particular with new material on high energy-density physics, nuclear explosions and other nuclear transformation processes.

  5. EXTREME METEOROLOGICAL CONDITIONS AND METABOLIC PROFILE IN HIGH YIELDING HOLSTEINFRIESIAN DAIRY COWS

    Directory of Open Access Journals (Sweden)

    Z. GERGÁCZ

    2008-10-01

    Full Text Available The impact of two years (2002 and 2003 with different summer temperature extremes on variation in metabolic profile was analyzed in blood and urine samples taken from healthy, primiparous (n = 371 and multiparous (n = 795 high yielding Holstein-Friesian dairy cows. In this study main focus was lead on three most critical physiological phases, thus cows were assigned into three groups as follows: (1 dry cows for 10 days prior to calving; (2 cows 1-30 days after delivery, and (3 cows with more than 31 days post partum. Findings reveal clear response of the cows to heat in selected blood (hemoglobin, plasma aceto-acetic-acid, FFA, AST, glucose, urea and urine (pH, NABE and urea parameters. In the majority of cows, glucose and hemoglobin level, one of the most significant blood parameters, indicated symptoms of insufficient energy supply. Further metabolic indicators differed more or less from reference values depending on actual condition. Due to heat load dry matter intake has been decreased even by 10-15 per cent in primiparous cows. They were expected to increase body weight and size and simultaneously produce attain at large milk yields. In doing so that cows would have require large amount of nutrients. Out of parameters such as hemoglobin, glucose, FFA, AST and blood-urea differed from the reference values in most cases; however, this phenomenon seemed to be present in almost every case for hemoglobin and glucose. The lack of energy caused by heat stress can be contributed to the decrease of dry matter intake which has been indicated by the urea levels and pH both in blood and urine prevailing unfavorable and insufficient feeding practice. The results reconfirm the need to reconsider both the actual feeding practice (e.g. to increase of nutrient content in rations, reduce the intake of soluble proteins in rumen, pay attention of crude fiber in Total Mixed Rations (TMR, NDF and ADF, avoid overfeeding of inorganic buffers, to control moisture

  6. Community responses to extreme climatic conditions

    Directory of Open Access Journals (Sweden)

    Frédéric JIGUET, Lluis BROTONS, Vincent DEVICTOR

    2011-06-01

    Full Text Available Species assemblages and natural communities are increasingly impacted by changes in the frequency and severity of extreme climatic events. Here we propose a brief overview of expected and demonstrated direct and indirect impacts of extreme events on animal communities. We show that differential impacts on basic biological parameters of individual species can lead to strong changes in community composition and structure with the potential to considerably modify the functional traits of the community. Sudden disequilibria have even been shown to induce irreversible shifts in marine ecosystems, while cascade effects on various taxonomic groups have been highlighted in Mediterranean forests. Indirect effects of extreme climatic events are expected when event-induced habitat changes (e.g. soil stability, vegetation composition, water flows altered by droughts, floods or hurricanes have differential consequences on species assembled within the communities. Moreover, in increasing the amplitude of trophic mismatches, extreme events are likely to turn many systems into ecological traps under climate change. Finally, we propose a focus on the potential impacts of an extreme heat wave on local assemblages as an empirical case study, analysing monitoring data on breeding birds collected in France. In this example, we show that despite specific populations were differently affected by local temperature anomalies, communities seem to be unaffected by a sudden heat wave. These results suggest that communities are tracking climate change at the highest possible rate [Current Zoology 57 (3: 406–413, 2011].

  7. A statistical methodology for the estimation of extreme wave conditions for offshore renewable applications

    DEFF Research Database (Denmark)

    Larsén, Xiaoli Guo; Kalogeri, Christina; Galanis, George

    2015-01-01

    and post-process outputs from a high resolution numerical wave modeling system for extreme wave estimation based on the significant wave height. This approach is demonstrated through the data analysis at a relatively deep water site, FINO 1, as well as a relatively shallow water area, coastal site Horns...... as a characteristic index of extreme wave conditions. The results from the proposed methodology seem to be in a good agreement with the measurements at both the relatively deep, open water and the shallow, coastal water sites, providing a potentially useful tool for offshore renewable energy applications. © 2015...... Rev, which is located in the North Sea, west of Denmark. The post-processing targets at correcting the modeled time series of the significant wave height, in order to match the statistics of the corresponding measurements, including not only the conventional parameters such as the mean and standard...

  8. Extreme summer temperatures in Iberia: health impacts and associated synoptic conditions

    Directory of Open Access Journals (Sweden)

    R. García-Herrera

    2005-02-01

    Full Text Available This paper examines the effect of extreme summer temperatures on daily mortality in two large cities of Iberia: Lisbon (Portugal and Madrid (Spain. Daily mortality and meteorological variables are analysed using the same methodology based on Box-Jenkins models. Results reveal that in both cases there is a triggering effect on mortality when maximum daily temperature exceeds a given threshold (34°C in Lisbon and 36°C in Madrid. The impact of most intense heat events is very similar for both cities, with significant mortality values occurring up to 3 days after the temperature threshold has been surpassed. This impact is measured as the percentual increase of mortality associated to a 1°C increase above the threshold temperature. In this respect, Lisbon shows a higher impact, 31%, as compared with Madrid at 21%. The difference can be attributed to demographic and socio-economic factors. Furthermore, the longer life span of Iberian women is critical to explain why, in both cities, females are more susceptible than males to heat effects, with an almost double mortality impact value. The analysis of Sea Level Pressure (SLP, 500hPa geopotential height and temperature fields reveals that, despite being relatively close to each other, Lisbon and Madrid have relatively different synoptic circulation anomalies associated with their respective extreme summer temperature days. The SLP field reveals higher anomalies for Lisbon, but extending over a smaller area. Extreme values in Madrid seem to require a more western location of the Azores High, embracing a greater area over Europe, even if it is not as deep as for Lisbon. The origin of the hot and dry air masses that usually lead to extreme heat days in both cities is located in Northern Africa. However, while Madrid maxima require wind blowing directly from the south, transporting heat from Southern Spain and Northern Africa, Lisbon maxima occur under more easterly conditions, when Northern African air

  9. Extreme summer temperatures in Iberia: health impacts and associated synoptic conditions

    Directory of Open Access Journals (Sweden)

    R. García-Herrera

    2005-02-01

    Full Text Available This paper examines the effect of extreme summer temperatures on daily mortality in two large cities of Iberia: Lisbon (Portugal and Madrid (Spain. Daily mortality and meteorological variables are analysed using the same methodology based on Box-Jenkins models. Results reveal that in both cases there is a triggering effect on mortality when maximum daily temperature exceeds a given threshold (34°C in Lisbon and 36°C in Madrid. The impact of most intense heat events is very similar for both cities, with significant mortality values occurring up to 3 days after the temperature threshold has been surpassed. This impact is measured as the percentual increase of mortality associated to a 1°C increase above the threshold temperature. In this respect, Lisbon shows a higher impact, 31%, as compared with Madrid at 21%. The difference can be attributed to demographic and socio-economic factors. Furthermore, the longer life span of Iberian women is critical to explain why, in both cities, females are more susceptible than males to heat effects, with an almost double mortality impact value.

    The analysis of Sea Level Pressure (SLP, 500hPa geopotential height and temperature fields reveals that, despite being relatively close to each other, Lisbon and Madrid have relatively different synoptic circulation anomalies associated with their respective extreme summer temperature days. The SLP field reveals higher anomalies for Lisbon, but extending over a smaller area. Extreme values in Madrid seem to require a more western location of the Azores High, embracing a greater area over Europe, even if it is not as deep as for Lisbon. The origin of the hot and dry air masses that usually lead to extreme heat days in both cities is located in Northern Africa. However, while Madrid maxima require wind blowing directly from the south, transporting heat from Southern Spain and Northern Africa, Lisbon maxima occur under more easterly

  10. Development of a system for simultaneously generating triple extreme conditions for neutron scattering experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ichimura, Shigeju [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    We have developed new system available for controlling sample environment during the neutron scattering experiments. The system can simultaneously generate triple extreme conditions of low temperature, high magnetic field and high pressure. The system consists of : (1) a liquid-helium cryostat which enables the sample temperature range of 1.7 K to 200 K, (2) a superconducting magnet providing a vertical field up to 5 Tesla with antisymmetric split-coil geometry for polarized-beam experiments, and (3) a non-magnetic clamping high-pressure cell designed with the aim of generating hydrostatic pressure up to 2.5 Gpa. In the workshop, we will report the outline of the system and some results of performance tests using the system at JRR-3M of JAERI. (author)

  11. Extreme Unconditional Dependence Vs. Multivariate GARCH Effect in the Analysis of Dependence Between High Losses on Polish and German Stock Indexes

    Science.gov (United States)

    Rokita, Pawel

    Classical portfolio diversification methods do not take account of any dependence between extreme returns (losses). Many researchers provide, however, some empirical evidence for various assets that extreme-losses co-occur. If the co-occurrence is frequent enough to be statistically significant, it may seriously influence portfolio risk. Such effects may result from a few different properties of financial time series, like for instance: (1) extreme dependence in a (long-term) unconditional distribution, (2) extreme dependence in subsequent conditional distributions, (3) time-varying conditional covariance, (4) time-varying (long-term) unconditional covariance, (5) market contagion. Moreover, a mix of these properties may be present in return time series. Modeling each of them requires different approaches. It seams reasonable to investigate whether distinguishing between the properties is highly significant for portfolio risk measurement. If it is, identifying the effect responsible for high loss co-occurrence would be of a great importance. If it is not, the best solution would be selecting the easiest-to-apply model. This article concentrates on two of the aforementioned properties: extreme dependence (in a long-term unconditional distribution) and time-varying conditional covariance.

  12. Establishment and performance of an experimental green roof under extreme climatic conditions.

    Science.gov (United States)

    Klein, Petra M; Coffman, Reid

    2015-04-15

    Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April-October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating

  13. Effective interactions for extreme isospin conditions; Interactions effectives pour des conditions extremes d`isospin

    Energy Technology Data Exchange (ETDEWEB)

    Chabanat, E.

    1995-01-01

    One of the main goal in nuclear physics research is the study of nuclei in extreme conditions of spin and isospin. The more performing tools for theoretical predictions in this field are microscopic methods such as the Hartree-Fock one based on independent particle approximation. The main ingredient for such an approach is the effective nucleon-nucleon interaction. The actual trend being the study of nuclei more and more far from the stability valley, it is necessary to cast doubt over the validity of usual effective interaction. This work constitute a study on the way one can construct a new interaction allowing some theoretical predictions on nuclei far from the stability. We have thus made a complete study of symmetric infinite nuclear matter and asymmetric one up to pure neutron matter. One shows that the asymmetry coefficient, which was considered until now as fixing isospin properties, is not sufficient to have a correct description of very exotic isospin states. A new type of constraint is shown for fixing this degree of freedom: the neutron matter equation of state. One include this equation of state, taken from a theoretical model giving a good description of radii and masses of neutron stars. One can thus expect to build up new Skyrme interaction with realistic properties of ground state of very neutron-rich nuclei. (author). 63 refs., 68 figs., 15 tabs.

  14. Organizing of medical ensurance of human population under extreme conditions. Summaries of reports of scientific-practical conference

    International Nuclear Information System (INIS)

    1994-01-01

    Summary of reports are presented of Scientific-Practical conference on the organizing of medical ensurance of human population under extreme conditions including radiation accidents. The conference held in Moscow in October, 1994. It covered problems of organizing medical ensurance of population, medical surveillance problems, sanitary-hygienic and epidemiological problems (including radiation protection), and medical provision problems under extreme conditions

  15. Extreme hydrothermal conditions at an active plate-bounding fault

    Science.gov (United States)

    Sutherland, Rupert; Townend, John; Toy, Virginia; Upton, Phaedra; Coussens, Jamie; Allen, Michael; Baratin, Laura-May; Barth, Nicolas; Becroft, Leeza; Boese, Carolin; Boles, Austin; Boulton, Carolyn; Broderick, Neil G. R.; Janku-Capova, Lucie; Carpenter, Brett M.; Célérier, Bernard; Chamberlain, Calum; Cooper, Alan; Coutts, Ashley; Cox, Simon; Craw, Lisa; Doan, Mai-Linh; Eccles, Jennifer; Faulkner, Dan; Grieve, Jason; Grochowski, Julia; Gulley, Anton; Hartog, Arthur; Howarth, Jamie; Jacobs, Katrina; Jeppson, Tamara; Kato, Naoki; Keys, Steven; Kirilova, Martina; Kometani, Yusuke; Langridge, Rob; Lin, Weiren; Little, Timothy; Lukacs, Adrienn; Mallyon, Deirdre; Mariani, Elisabetta; Massiot, Cécile; Mathewson, Loren; Melosh, Ben; Menzies, Catriona; Moore, Jo; Morales, Luiz; Morgan, Chance; Mori, Hiroshi; Niemeijer, Andre; Nishikawa, Osamu; Prior, David; Sauer, Katrina; Savage, Martha; Schleicher, Anja; Schmitt, Douglas R.; Shigematsu, Norio; Taylor-Offord, Sam; Teagle, Damon; Tobin, Harold; Valdez, Robert; Weaver, Konrad; Wiersberg, Thomas; Williams, Jack; Woodman, Nick; Zimmer, Martin

    2017-06-01

    Temperature and fluid pressure conditions control rock deformation and mineralization on geological faults, and hence the distribution of earthquakes. Typical intraplate continental crust has hydrostatic fluid pressure and a near-surface thermal gradient of 31 ± 15 degrees Celsius per kilometre. At temperatures above 300-450 degrees Celsius, usually found at depths greater than 10-15 kilometres, the intra-crystalline plasticity of quartz and feldspar relieves stress by aseismic creep and earthquakes are infrequent. Hydrothermal conditions control the stability of mineral phases and hence frictional-mechanical processes associated with earthquake rupture cycles, but there are few temperature and fluid pressure data from active plate-bounding faults. Here we report results from a borehole drilled into the upper part of the Alpine Fault, which is late in its cycle of stress accumulation and expected to rupture in a magnitude 8 earthquake in the coming decades. The borehole (depth 893 metres) revealed a pore fluid pressure gradient exceeding 9 ± 1 per cent above hydrostatic levels and an average geothermal gradient of 125 ± 55 degrees Celsius per kilometre within the hanging wall of the fault. These extreme hydrothermal conditions result from rapid fault movement, which transports rock and heat from depth, and topographically driven fluid movement that concentrates heat into valleys. Shear heating may occur within the fault but is not required to explain our observations. Our data and models show that highly anomalous fluid pressure and temperature gradients in the upper part of the seismogenic zone can be created by positive feedbacks between processes of fault slip, rock fracturing and alteration, and landscape development at plate-bounding faults.

  16. Extreme hydrothermal conditions at an active plate-bounding fault.

    Science.gov (United States)

    Sutherland, Rupert; Townend, John; Toy, Virginia; Upton, Phaedra; Coussens, Jamie; Allen, Michael; Baratin, Laura-May; Barth, Nicolas; Becroft, Leeza; Boese, Carolin; Boles, Austin; Boulton, Carolyn; Broderick, Neil G R; Janku-Capova, Lucie; Carpenter, Brett M; Célérier, Bernard; Chamberlain, Calum; Cooper, Alan; Coutts, Ashley; Cox, Simon; Craw, Lisa; Doan, Mai-Linh; Eccles, Jennifer; Faulkner, Dan; Grieve, Jason; Grochowski, Julia; Gulley, Anton; Hartog, Arthur; Howarth, Jamie; Jacobs, Katrina; Jeppson, Tamara; Kato, Naoki; Keys, Steven; Kirilova, Martina; Kometani, Yusuke; Langridge, Rob; Lin, Weiren; Little, Timothy; Lukacs, Adrienn; Mallyon, Deirdre; Mariani, Elisabetta; Massiot, Cécile; Mathewson, Loren; Melosh, Ben; Menzies, Catriona; Moore, Jo; Morales, Luiz; Morgan, Chance; Mori, Hiroshi; Niemeijer, Andre; Nishikawa, Osamu; Prior, David; Sauer, Katrina; Savage, Martha; Schleicher, Anja; Schmitt, Douglas R; Shigematsu, Norio; Taylor-Offord, Sam; Teagle, Damon; Tobin, Harold; Valdez, Robert; Weaver, Konrad; Wiersberg, Thomas; Williams, Jack; Woodman, Nick; Zimmer, Martin

    2017-06-01

    Temperature and fluid pressure conditions control rock deformation and mineralization on geological faults, and hence the distribution of earthquakes. Typical intraplate continental crust has hydrostatic fluid pressure and a near-surface thermal gradient of 31 ± 15 degrees Celsius per kilometre. At temperatures above 300-450 degrees Celsius, usually found at depths greater than 10-15 kilometres, the intra-crystalline plasticity of quartz and feldspar relieves stress by aseismic creep and earthquakes are infrequent. Hydrothermal conditions control the stability of mineral phases and hence frictional-mechanical processes associated with earthquake rupture cycles, but there are few temperature and fluid pressure data from active plate-bounding faults. Here we report results from a borehole drilled into the upper part of the Alpine Fault, which is late in its cycle of stress accumulation and expected to rupture in a magnitude 8 earthquake in the coming decades. The borehole (depth 893 metres) revealed a pore fluid pressure gradient exceeding 9 ± 1 per cent above hydrostatic levels and an average geothermal gradient of 125 ± 55 degrees Celsius per kilometre within the hanging wall of the fault. These extreme hydrothermal conditions result from rapid fault movement, which transports rock and heat from depth, and topographically driven fluid movement that concentrates heat into valleys. Shear heating may occur within the fault but is not required to explain our observations. Our data and models show that highly anomalous fluid pressure and temperature gradients in the upper part of the seismogenic zone can be created by positive feedbacks between processes of fault slip, rock fracturing and alteration, and landscape development at plate-bounding faults.

  17. Influence of the emotional state on behavior in extreme conditions of competitive sports activities

    Directory of Open Access Journals (Sweden)

    V.A. Malakhov

    2014-04-01

    Full Text Available Purpose : establish a communication pattern of emotional intensity and level of extreme environment in which activity is performed. Materials : in the study involved 600 men aged 18-22 years. Results : the effect of the emotional state on the efficiency of the motor activity that flowed under extreme conditions. Set individual characteristics flow sports activities in extreme conditions. First used in the special semantic space for the orderly presentation of research results parachute jumps. The monogram built in semantic fields allows to establish the frequency response range of individual heartbeats and the optimal frequency for maximum performance. On the basis of established regularities of the "reflex of readiness" assessment methodology given emotional stress, which reflects the readiness of an individual to perform a parachute jump. An objective indicator of preparedness measures is a violation of the symmetry of the flow and haptic reflex and serial dynamometry. Conclusions : in using semantic spaces reflects the flowing of reflex of biological caution and accompaniment reflex. In the basis of constructing estimates of emotional stress are the regularities of mean arterial pressure as nonspecific reactions. Measure of extent of confused is estimated by variability of accompaniment reflex. Breach of symmetry in mean arterial pressure and the amplitude - frequency response accompaniment reflex, determine the validity of staying in extreme conditions. Introduction of the measure in using semantic spaces allows by selective data to establish the overall structure of the studied process.

  18. Influence of the emotional state on behavior in extreme conditions of competitive sports activities

    Directory of Open Access Journals (Sweden)

    Malakhov V.A.

    2014-03-01

    Full Text Available Purpose : establish a communication pattern of emotional intensity and level of extreme environment in which activity is performed. Materials : in the study involved 600 men aged 18-22 years. Results : the effect of the emotional state on the efficiency of the motor activity that flowed under extreme conditions. Set individual characteristics flow sports activities in extreme conditions. First used in the special semantic space for the orderly presentation of research results parachute jumps. The monogram built in semantic fields allows to establish the frequency response range of individual heartbeats and the optimal frequency for maximum performance. On the basis of established regularities of the "reflex of readiness" assessment methodology given emotional stress, which reflects the readiness of an individual to perform a parachute jump. An objective indicator of preparedness measures is a violation of the symmetry of the flow and haptic reflex and serial dynamometry. Conclusions : in using semantic spaces reflects the flowing of reflex of biological caution and accompaniment reflex. In the basis of constructing estimates of emotional stress are the regularities of mean arterial pressure as nonspecific reactions. Measure of extent of confused is estimated by variability of accompaniment reflex. Breach of symmetry in mean arterial pressure and the amplitude - frequency response accompaniment reflex, determine the validity of staying in extreme conditions. Introduction of the measure in using semantic spaces allows by selective data to establish the overall structure of the studied process.

  19. Improving multisensor estimation of heavy-to-extreme precipitation via conditional bias-penalized optimal estimation

    Science.gov (United States)

    Kim, Beomgeun; Seo, Dong-Jun; Noh, Seong Jin; Prat, Olivier P.; Nelson, Brian R.

    2018-01-01

    A new technique for merging radar precipitation estimates and rain gauge data is developed and evaluated to improve multisensor quantitative precipitation estimation (QPE), in particular, of heavy-to-extreme precipitation. Unlike the conventional cokriging methods which are susceptible to conditional bias (CB), the proposed technique, referred to herein as conditional bias-penalized cokriging (CBPCK), explicitly minimizes Type-II CB for improved quantitative estimation of heavy-to-extreme precipitation. CBPCK is a bivariate version of extended conditional bias-penalized kriging (ECBPK) developed for gauge-only analysis. To evaluate CBPCK, cross validation and visual examination are carried out using multi-year hourly radar and gauge data in the North Central Texas region in which CBPCK is compared with the variant of the ordinary cokriging (OCK) algorithm used operationally in the National Weather Service Multisensor Precipitation Estimator. The results show that CBPCK significantly reduces Type-II CB for estimation of heavy-to-extreme precipitation, and that the margin of improvement over OCK is larger in areas of higher fractional coverage (FC) of precipitation. When FC > 0.9 and hourly gauge precipitation is > 60 mm, the reduction in root mean squared error (RMSE) by CBPCK over radar-only (RO) is about 12 mm while the reduction in RMSE by OCK over RO is about 7 mm. CBPCK may be used in real-time analysis or in reanalysis of multisensor precipitation for which accurate estimation of heavy-to-extreme precipitation is of particular importance.

  20. Atmospheric conditions and weather regimes associated with extreme winter dry spells over the Mediterranean basin

    Science.gov (United States)

    Raymond, Florian; Ullmann, Albin; Camberlin, Pierre; Oueslati, Boutheina; Drobinski, Philippe

    2018-06-01

    Very long dry spell events occurring during winter are natural hazards to which the Mediterranean region is extremely vulnerable, because they can lead numerous impacts for environment and society. Four dry spell patterns have been identified in a previous work. Identifying the main associated atmospheric conditions controlling the dry spell patterns is key to better understand their dynamics and their evolution in a changing climate. Except for the Levant region, the dry spells are generally associated with anticyclonic blocking conditions located about 1000 km to the Northwest of the affected area. These anticyclonic conditions are favourable to dry spell occurrence as they are associated with subsidence of cold and dry air coming from boreal latitudes which bring low amount of water vapour and non saturated air masses, leading to clear sky and absence of precipitation. These extreme dry spells are also partly related to the classical four Euro-Atlantic weather regimes are: the two phases of the North Atlantic Oscillation, the Scandinavian "blocking" or "East-Atlantic", and the "Atlantic ridge". Only the The "East-Atlantic", "Atlantic ridge" and the positive phase of the North Atlantic Oscillation are frequently associated with extremes dry spells over the Mediterranean basin but they do not impact the four dry spell patterns equally. Finally long sequences of those weather regimes are more favourable to extreme dry spells than short sequences. These long sequences are associated with the favourable prolonged and reinforced anticyclonic conditions

  1. Condensed Matter NMR under Extreme Conditions: Challenges and Opportunities

    Science.gov (United States)

    Reyes, Arneil

    2006-11-01

    Advances in resistive magnet and power supply technology have made available extremely high magnetic fields suitable for condensed matter broadline NMR experiments. This capability expands the available phase space for investigating a wide variety of materials using magnetic resonance; utilizing the strength of the field to expose or induce new physical phenomena resulting in better understanding of the physics. Continuous fields up to 45T in NHMFL Hybrid magnet have brought new challenges in designing NMR instrumentation. Field strengths and sample space limitations put constraints on RF pulse power, tuning range, bandwidth, and temperature control. The inclusion of other capabilities, including high pressure, optics, and sample rotation requires intricate probe design and construction, while extremely low milliKelvin temperatures are desired in order to explore energy scales where thermal fluctuations are suppressed. Optimization of these devices has been of paramount consideration in NHMFL Condensed Matter NMR user program. Science achieved at high fields, the new initiatives to develop resistively-detected NMR in 2D electron gas and similar systems, and the current new generation Series-Connected Hybrid magnets for NMR work will be discussed. The NHMFL is supported by the National Science Foundation and the State of Florida.

  2. Matter in Extreme Conditions Instrument - Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, R.F.; Boyce, R.M.; Haller, G.; Hastings, J.B.; Hays, G.; Lee, H.J.; /SLAC; Lee, R.W.; /LLNL, Livermore; Nagler, B.; /Rutherford; Scharfenstein, M.; Marsh, D.; White, W.E.; /SLAC

    2009-12-09

    The SLAC National Accelerator Laboratory (SLAC), in collaboration with Argonne National Laboratory (ANL), Lawrence Livermore National Laboratory (LLNL), and the University of California at Los Angeles (UCLA), is constructing a Free-Electron Laser (FEL) research facility. The FEL has already met its performance goals in the wavelength range 1.5 nm - 0.15 nm. This facility, the Linac Coherent Light Source (LCLS), utilizes the SLAC 2-Mile Linear Accelerator (linac) and will produce sub-picosecond pulses of short wavelength X-rays with very high peak brightness and almost complete transverse coherence. The final one-third of the SLAC linac is used as the source of electrons for the LCLS. The high energy electrons are transported across the SLAC Research Yard, into a tunnel which houses a long undulator. In passing through the undulator, the electrons are bunched by the force of their own synchrotron radiation and produce an intense, monochromatic, spatially coherent beam of X-rays. By varying the electron energy, the FEL X-ray wavelength is tunable from 1.5 nm to 0.15 nm. The LCLS includes two experimental halls as well as X-ray optics and infrastructure necessary to create a facility that can be developed for research in a variety of disciplines such as atomic physics, materials science, plasma physics and biosciences. This Conceptual Design Report, the authors believe, confirms the feasibility of designing and constructing an X-ray instrument in order to exploit the unique scientific capability of LCLS by creating extreme conditions and study the behavior of plasma under those controlled conditions. This instrument will address the Office of Science, Fusion Energy Sciences, mission objective related to study of Plasma and Warm Dense Matter as described in the report titled LCLS, the First Experiments, prepared by the LCLS Scientific Advisory Committee (SAC) in September 2000. The technical objective of the LCLS Matter in Extreme Conditions (MEC) Instrument project is

  3. Technology development of protein rich concentrates for nutrition in extreme conditions using soybean and meat by-products.

    Science.gov (United States)

    Kalenik, Tatiana K; Costa, Rui; Motkina, Elena V; Kosenko, Tamara A; Skripko, Olga V; Kadnikova, Irina A

    2017-01-01

    There is a need to develop new foods for participants of expeditions in extreme conditions, which must be self-sufficient. These foods should be light to carry, with a long shelf life, tasty and with  high nutrient density. Currently, protein sources are limited mainly to dried and canned meat. In this work, a protein-rich dried concentrate suitable for extreme expeditions was developed using soya, tomato, milk whey and meat by-products. Protein concentrates were developed using minced beef liver and heart, dehydrated and mixed with a soya protein-lycopene coagulate (SPLC) obtained from a solution prepared with germi- nated soybeans and mixed with tomato paste in milk whey, and finally dried. The technological parameters of pressing SPLC and of drying the protein concentrate were optimized using response surface methodology. The optimized technological parameters to prepare the protein concentrates were obtained, with 70:30 being the ideal ratio of minced meat to SPLC. The developed protein concentrates are characterized by a high calorific value of 376 kcal/100 g of dry product, with a water content of 98 g·kg-1, and 641-644 g·kg-1 of proteins. The essential amino acid indices are 100, with minimum essential amino acid content constitut- ing 100-128% of the FAO standard, depending on the raw meat used. These concentrates are also rich in micronutrients such as β-carotene and vitamin C. Analysis of the nutrient content showed that these non-perishable concentrates present a high nutritional value and complement other widely available vegetable concentrates to prepare a two-course meal. The soups and porridges prepared with these concentrates can be classified as functional foods, and comply with army requirements applicable to food products for extreme conditions.

  4. Alginate Adsorbent Immobilization Technique Promotes Biobutanol Production by Clostridium acetobutylicum Under Extreme Condition of High Concentration of Organic Solvent

    Directory of Open Access Journals (Sweden)

    Zhuoliang Ye

    2018-05-01

    Full Text Available In Acetone-Butanol-Ethanol fermentation, bacteria should tolerate high concentrations of solvent products, which inhibit bacteria growth and limit further increase of solvents to more than 20 g/L. Moreover, this limited solvent concentration significantly increases the cost of solvent separation through traditional approaches. In this study, alginate adsorbent immobilization technique was successfully developed to assist in situ extraction using octanol which is effective in extracting butanol but presents strong toxic effect to bacteria. The adsorbent improved solvent tolerance of Clostridium acetobutylicum under extreme condition of high concentration of organic solvent. Using the developed technique, more than 42% of added bacteria can be adsorbed to the adsorbent. Surface area of the adsorbent was more than 10 times greater than sodium alginate. Scanning electron microscope image shows that an abundant amount of pore structure was successfully developed on adsorbents, promoting bacteria adsorption. In adsorbent assisted ABE fermentation, there was 21.64 g/L butanol in extracting layer compared to negligible butanol produced with only the extractant but without the adsorbent, for the reason that adsorbent can reduce damaging exposure of C. acetobutylicum to octanol. The strategy can improve total butanol production with respect to traditional culture approach by more than 2.5 fold and save energy for subsequent butanol recovery, which effects can potentially make the biobutanol production more economically practical.

  5. Regional metamorphism at extreme conditions: Implications for orogeny at convergent plate margins

    Science.gov (United States)

    Zheng, Yong-Fei; Chen, Ren-Xu

    2017-09-01

    Regional metamorphism at extreme conditions refers either to Alpine-type metamorphism at low geothermal gradients of geothermal gradients of >30 °C/km. Extreme pressures refer to those above the polymorphic transition of quartz to coesite, so that ultrahigh-pressure (UHP) eclogite-facies metamorphism occurs at mantle depths of >80 km. Extreme temperatures refer to those higher than 900 °C at crustal depths of ≤80 km, so that ultrahigh-temperature (UHT) granulite-facies metamorphism occurs at medium to high pressures. While crustal subduction at the low geothermal gradients results in blueschist-eclogite facies series without arc volcanism, heating of the thinned orogenic lithosphere brings about the high geothermal gradients for amphibolite-granulite facies series with abundant magmatism. Therefore, UHP metamorphic rocks result from cold lithospheric subduction to the mantle depths, whereas UHT metamorphic rocks are produced by hot underplating of the asthenospheric mantle at the crustal depths. Active continental rifting is developed on the thinned lithosphere in response to asthenospheric upwelling, and this tectonism is suggested as a feasible mechanism for regional granulite-facies metamorphism, with the maximum temperature depending on the extent to which the mantle lithosphere is thinned prior to the rifting. While lithospheric compression is associated with subduction metamorphism in accretionary and collisional orogens, the thinned orogenic lithosphere undergoes extension due to the asthenospheric upwelling to result in orogen-parallel rifting metamorphism and magmatism. Thus, the rifting metamorphism provides a complement to the subduction metamorphism and its operation marks the asthenospheric heating of the orogenic lithosphere. Because of the partial melting and melt extraction of the lower continental crust, contemporaneous granite-migmatite-granulite associations may serve as a petrological indicator of rifting orogeny that is superimposed on

  6. Observations and Predictions of Wave Runup, Extreme Water Levels, and Medium-Term Dune Erosion during Storm Conditions

    Directory of Open Access Journals (Sweden)

    Serge Suanez

    2015-07-01

    Full Text Available Monitoring of dune erosion and accretion on the high-energy macrotidal Vougot beach in North Brittany (France over the past decade (2004–2014 has revealed significant morphological changes. Dune toe erosion/accretion records have been compared with extreme water level measurements, defined as the sum of (i astronomic tide; (ii storm surge; and (iii vertical wave runup. Runup parameterization was conducted using swash limits, beach profiles, and hydrodynamic (Hm0, Tm0,–1, and high tide water level—HTWL data sets obtained from high frequency field surveys. The aim was to quantify in-situ environmental conditions and dimensional swash parameters for the best calibration of Battjes [1] runup formula. In addition, an empirical equation based on observed tidal water level and offshore wave height was produced to estimate extreme water levels over the whole period of dune morphological change monitoring. A good correlation between this empirical equation (1.01Hmoξo and field runup measurements (Rmax was obtained (R2 85%. The goodness of fit given by the RMSE was about 0.29 m. A good relationship was noticed between dune erosion and high water levels when the water levels exceeded the dune foot elevation. In contrast, when extreme water levels were below the height of the toe of the dune sediment budget increased, inducing foredune recovery. These erosion and accretion phases may be related to the North Atlantic Oscillation Index.

  7. "On-off-on" switchable sensor: a fluorescent spiropyran responds to extreme pH conditions and its bioimaging applications.

    Science.gov (United States)

    Wan, Shulin; Zheng, Yang; Shen, Jie; Yang, Wantai; Yin, Meizhen

    2014-11-26

    A novel spiropyran that responds to both extreme acid and extreme alkali and has an "on-off-on" switch is reported. Benzoic acid at the indole N-position and carboxyl group at the indole 6-position contribute to the extreme acid response. The ionizations of carboxyl and phenolic hydroxyl groups cause the extreme alkali response. Moreover, the fluorescent imaging in bacterial cells under extreme pH conditions supports the mechanism of pH response.

  8. Polygenic determinants in extremes of high-density lipoprotein cholesterol.

    Science.gov (United States)

    Dron, Jacqueline S; Wang, Jian; Low-Kam, Cécile; Khetarpal, Sumeet A; Robinson, John F; McIntyre, Adam D; Ban, Matthew R; Cao, Henian; Rhainds, David; Dubé, Marie-Pierre; Rader, Daniel J; Lettre, Guillaume; Tardif, Jean-Claude; Hegele, Robert A

    2017-11-01

    HDL cholesterol (HDL-C) remains a superior biochemical predictor of CVD risk, but its genetic basis is incompletely defined. In patients with extreme HDL-C concentrations, we concurrently evaluated the contributions of multiple large- and small-effect genetic variants. In a discovery cohort of 255 unrelated lipid clinic patients with extreme HDL-C levels, we used a targeted next-generation sequencing panel to evaluate rare variants in known HDL metabolism genes, simultaneously with common variants bundled into a polygenic trait score. Two additional cohorts were used for validation and included 1,746 individuals from the Montréal Heart Institute Biobank and 1,048 individuals from the University of Pennsylvania. Findings were consistent between cohorts: we found rare heterozygous large-effect variants in 18.7% and 10.9% of low- and high-HDL-C patients, respectively. We also found common variant accumulation, indicated by extreme polygenic trait scores, in an additional 12.8% and 19.3% of overall cases of low- and high-HDL-C extremes, respectively. Thus, the genetic basis of extreme HDL-C concentrations encountered clinically is frequently polygenic, with contributions from both rare large-effect and common small-effect variants. Multiple types of genetic variants should be considered as contributing factors in patients with extreme dyslipidemia. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  9. Heavy fermions and extreme conditions

    International Nuclear Information System (INIS)

    Cheikine, Ilia

    2000-01-01

    Three heavy electron systems, CeCu 2 Si 2 , CePd 2 Si 2 and UGe 2 , were investigated by transport, quantum oscillations (CePd 2 Si 2 ) and neutron diffraction (UGe 2 ) measurements. The experiments were performed under extreme conditions of very low temperature, high magnetic field and hydrostatic pressure. In the case of CeCu 2 Si 2 , we followed the evolution of the magnetic A-phase that is found to collapse rapidly under pressure. We found evidence for a relation between the A-phase and the presence of a maximum in the temperature dependence of H c2 . Our analysis showed that at low pressure, the sign of the exchange integral should be negative, thus superconductivity is enhanced by an increase in the paramagnetic susceptibility as in the Jaccarino-Peter effect. The anisotropy of the initial slope of H c2 and therefore that of the effective mass was found to change under pressure. For CePd 2 Si 2 , both the de Haas-van Alphen effect at ambient pressure and the electrical resistivity under pressure were studied. The latter reveals a non-Fermi liquid behavior in the vicinity of the antiferromagnetic quantum critical point, P c ∼ kbar. The analysis of H c2 at P c shows that the superconducting state is well described by a weak coupling, clean limit model with a slightly anisotropic orbital limit and a strongly anisotropic paramagnetic one. UGe 2 is shown to demonstrate the coexistence of ferromagnetism and superconductivity that develops just below the ferromagnetic quantum critical point, P c ∼16 kbar. The measurements of the resistivity under pressure point to a possible existence of another phase boundary and thus another quantum critical point, P x ∼ 12 kbar, within the ferromagnetic state. The P-T phase diagram containing both P c and P x was sketched, and a possible relation between P x and the development of superconductivity was discussed. The temperature dependence of H c2 demonstrates a variety of novel behaviors, which cannot be understood within

  10. Necessary and sufficient conditions for big bangs, bounces, crunches, rips, sudden singularities and extremality events

    International Nuclear Information System (INIS)

    Cattoen, Celine; Visser, Matt

    2005-01-01

    Until recently, the physically relevant singularities occurring in FRW cosmologies had traditionally been thought to be limited to the 'big bang', and possibly a 'big crunch'. However, over the last few years, the zoo of cosmological singularities considered in the literature has become considerably more extensive, with 'big rips' and 'sudden singularities' added to the mix, as well as renewed interest in nonsingular cosmological events such as 'bounces' and 'turnarounds'. In this paper we present an extensive catalogue of such cosmological milestones, both at the kinematical and dynamical level. First, using generalized power series, purely kinematical definitions of these cosmological events are provided in terms of the behaviour of the scale factor a(t). The notion of a 'scale-factor singularity' is defined, and its relation to curvature singularities (polynomial and differential) is explored. Second, dynamical information is extracted by using the Friedmann equations (without assuming even the existence of any equation of state) to place constraints on whether or not the classical energy conditions are satisfied at the cosmological milestones. We use these considerations to derive necessary and sufficient conditions for the existence of cosmological milestones such as bangs, bounces, crunches, rips, sudden singularities and extremality events. Since the classification is extremely general and, modulo certain technical assumptions, is complete, the corresponding results are to a high degree model independent: in particular, we provide a characterization of the class of bangs, crunches and sudden singularities for which the dominant energy condition is satisfied

  11. Biological effects of extreme environmental conditions. [considering limits of biosphere

    Science.gov (United States)

    Imshenetskiy, A. A.

    1975-01-01

    Actions of extreme physical and chemical space factors on microorganisms and plants are elaborated in order to establish limits for the biosphere. Considered are effects of low and high temperatures; ionizing and ultraviolet radiation; various gases; and effects of vibration, desiccation and acceleration.

  12. Does red noise increase or decrease extinction risk? Single extreme events versus series of unfavorable conditions.

    Science.gov (United States)

    Schwager, Monika; Johst, Karin; Jeltsch, Florian

    2006-06-01

    Recent theoretical studies have shown contrasting effects of temporal correlation of environmental fluctuations (red noise) on the risk of population extinction. It is still debated whether and under which conditions red noise increases or decreases extinction risk compared with uncorrelated (white) noise. Here, we explain the opposing effects by introducing two features of red noise time series. On the one hand, positive autocorrelation increases the probability of series of poor environmental conditions, implying increasing extinction risk. On the other hand, for a given time period, the probability of at least one extremely bad year ("catastrophe") is reduced compared with white noise, implying decreasing extinction risk. Which of these two features determines extinction risk depends on the strength of environmental fluctuations and the sensitivity of population dynamics to these fluctuations. If extreme (catastrophic) events can occur (strong noise) or sensitivity is high (overcompensatory density dependence), then temporal correlation decreases extinction risk; otherwise, it increases it. Thus, our results provide a simple explanation for the contrasting previous findings and are a crucial step toward a general understanding of the effect of noise color on extinction risk.

  13. Extremely high concentration of folates in premature newborns.

    Science.gov (United States)

    Zikavska, T; Brucknerova, I

    2014-01-01

    Extremely high concentration of folates in premature newborns: case reports. Folates are a group of water soluble compounds, which are important for metabolic processes in human body. These are important during periods of rapid cell growth. The most accurate indicator of long-term folate level status in the body is the determination of red blood cell (RBC) folate concentrations. The optimal level of RBC folate is not known in neonatal period. Authors discuss the reasons for extremely high level of RBC folate concentrations. In our work we present the cases of two premature newborns with extremely high level of RBC folate concentrations, which were analyzed immunochemically on the first day of life and after six weeks of life. In both cases we measured RBC folate concentrations on the 1st day of life. After 6 weeks we found extremely high RBC folate concentration level (5516.67 ng/ml) in the first case after RBC transfusions. In second case after two months of life the RBC folate concentration level was doubled (2335.1 ng/ml) until 24 hours after RBC transfusion compared to levels after birth. The normal range of RBC folate values vary in newborns. The upper limit of daily dose of folic acid in pregnancy and neonatal period is not known. On the other hand it is an easily excreted water-soluble vitamin but in premature newborn it can lead to the disruption of metabolic balance and slow its degradation. Some factors can have an impact on RBC folate concentration. Blood transfusion can be one of the main influences on RBC folate concentration. To clarify these mechanisms further studies are required (Ref. 29).

  14. High-Resolution Dynamical Downscaling Ensemble Projections of Future Extreme Temperature Distributions for the United States

    Science.gov (United States)

    Zobel, Zachary; Wang, Jiali; Wuebbles, Donald J.; Kotamarthi, V. Rao

    2017-12-01

    The aim of this study is to examine projections of extreme temperatures over the continental United States (CONUS) for the 21st century using an ensemble of high spatial resolution dynamically downscaled model simulations with different boundary conditions. The downscaling uses the Weather Research and Forecast model at a spatial resolution of 12 km along with outputs from three different Coupled Model Intercomparison Project Phase 5 global climate models that provide boundary conditions under two different future greenhouse gas (GHG) concentration trajectories. The results from two decadal-length time slices (2045-2054 and 2085-2094) are compared with a historical decade (1995-2004). Probability density functions of daily maximum/minimum temperatures are analyzed over seven climatologically cohesive regions of the CONUS. The impacts of different boundary conditions as well as future GHG concentrations on extreme events such as heat waves and days with temperature higher than 95°F are also investigated. The results show that the intensity of extreme warm temperature in future summer is significantly increased, while the frequency of extreme cold temperature in future winter decreases. The distribution of summer daily maximum temperature experiences a significant warm-side shift and increased variability, while the distribution of winter daily minimum temperature is projected to have a less significant warm-side shift with decreased variability. Using "business-as-usual" scenario, 5-day heat waves are projected to occur at least 5-10 times per year in most CONUS and ≥95°F days will increase by 1-2 months by the end of the century.

  15. Numerical Analysis of Flood modeling of upper Citarum River under Extreme Flood Condition

    Science.gov (United States)

    Siregar, R. I.

    2018-02-01

    This paper focuses on how to approach the numerical method and computation to analyse flood parameters. Water level and flood discharge are the flood parameters solved by numerical methods approach. Numerical method performed on this paper for unsteady flow conditions have strengths and weaknesses, among others easily applied to the following cases in which the boundary irregular flow. The study area is in upper Citarum Watershed, Bandung, West Java. This paper uses computation approach with Force2 programming and HEC-RAS to solve the flow problem in upper Citarum River, to investigate and forecast extreme flood condition. Numerical analysis based on extreme flood events that have occurred in the upper Citarum watershed. The result of water level parameter modeling and extreme flood discharge compared with measurement data to analyse validation. The inundation area about flood that happened in 2010 is about 75.26 square kilometres. Comparing two-method show that the FEM analysis with Force2 programs has the best approach to validation data with Nash Index is 0.84 and HEC-RAS that is 0.76 for water level. For discharge data Nash Index obtained the result analysis use Force2 is 0.80 and with use HEC-RAS is 0.79.

  16. Numerical tools to predict the environmental loads for offshore structures under extreme weather conditions

    Science.gov (United States)

    Wu, Yanling

    2018-05-01

    In this paper, the extreme waves were generated using the open source computational fluid dynamic (CFD) tools — OpenFOAM and Waves2FOAM — using linear and nonlinear NewWave input. They were used to conduct the numerical simulation of the wave impact process. Numerical tools based on first-order (with and without stretching) and second-order NewWave are investigated. The simulation to predict force loading for the offshore platform under the extreme weather condition is implemented and compared.

  17. BEHAVIOUR OF BACKFILL MATERIALS FOR ELECTRICAL GROUNDING SYSTEMS UNDER HIGH VOLTAGE CONDITIONS

    Directory of Open Access Journals (Sweden)

    S. C. LIM

    2015-06-01

    Full Text Available Backfill materials like Bentonite and cement are effective in lowering grounding resistance of electrodes for a considerable period. During lightning, switching impulses and earth fault occurrences in medium and high voltage networks, the grounding system needs to handle extremely high currents either for a short duration or prolonged period respectively. This paper investigates the behaviour of bentonite, cement and sand under impulse and alternating high voltage (50Hz conditions. Fulguritic-formation was observed in all materials under alternating high voltage. The findings reveal that performance of grounding systems under high voltage conditions may significantly change from the outcomes anticipated at design stage.

  18. Crenarchaeal biofilm formation under extreme conditions.

    Directory of Open Access Journals (Sweden)

    Andrea Koerdt

    Full Text Available BACKGROUND: Biofilm formation has been studied in much detail for a variety of bacterial species, as it plays a major role in the pathogenicity of bacteria. However, only limited information is available for the development of archaeal communities that are frequently found in many natural environments. METHODOLOGY: We have analyzed biofilm formation in three closely related hyperthermophilic crenarchaeotes: Sulfolobus acidocaldarius, S. solfataricus and S. tokodaii. We established a microtitre plate assay adapted to high temperatures to determine how pH and temperature influence biofilm formation in these organisms. Biofilm analysis by confocal laser scanning microscopy demonstrated that the three strains form very different communities ranging from simple carpet-like structures in S. solfataricus to high density tower-like structures in S. acidocaldarius in static systems. Lectin staining indicated that all three strains produced extracellular polysaccharides containing glucose, galactose, mannose and N-acetylglucosamine once biofilm formation was initiated. While flagella mutants had no phenotype in two days old static biofilms of S. solfataricus, a UV-induced pili deletion mutant showed decreased attachment of cells. CONCLUSION: The study gives first insights into formation and development of crenarchaeal biofilms in extreme environments.

  19. Mean versus extreme climate in the Mediterranean region and its sensitivity to future global warming conditions

    Energy Technology Data Exchange (ETDEWEB)

    Paeth, H.; Hense, A. [Meteorological Inst., Univ. Bonn (Germany)

    2005-06-01

    The Mediterranean region (MTR) has been supposed to be very sensitive to changes in land surface and atmospheric greenhouse-gas (GHG) concentrations. Particularly, an intensification of climate extremes may be associated with severe socio-economic implications. Here, we present an analysis of climate mean and extreme conditions in this subtropical area based on regional climate model experiments, simulating the present-day and possible future climate. The analysis of extreme values (EVs) is based on the assumption that the extremes of daily precipitation and near-surface temperature are well fitted by the Generalized Pareto distribution (GPD). Return values of extreme daily events are determined using the method of L-moments. Particular emphasis is laid on the evaluation of the return values with respect to the uncertainty range of the estimate as derived from a Monte Carlo sampling approach. During the most recent 25 years the MTR has become dryer in spring but more humid especially in the western part in autumn and winter. At the same time, the whole region has been subject to a substantial warming. The strongest rainfall extremes are simulated in autumn over the Mediterranean Sea around Italy. Temperature extremes are most pronounced over the land masses, especially over northern Africa. Given the large uncertainty of the EV estimate, only 1-year return values are further analysed. During recent decades, statistically significant changes in extremes are only found for temperature. Future climate conditions may come along with a decrease in mean and extreme precipitation during the cold season, whereas an intensification of the hydrological cycle is predicted in summer and autumn. Temperature is predominantly affected over the Iberian Peninsula and the eastern part of the MTR. In many grid boxes, the signals are blurred out due to the large amount of uncertainty in the EV estimate. Thus, a careful analysis is required when making inferences about the future

  20. Polygenic determinants in extremes of high-density lipoprotein cholesterol[S

    Science.gov (United States)

    Dron, Jacqueline S.; Wang, Jian; Low-Kam, Cécile; Khetarpal, Sumeet A.; Robinson, John F.; McIntyre, Adam D.; Ban, Matthew R.; Cao, Henian; Rhainds, David; Dubé, Marie-Pierre; Rader, Daniel J.; Lettre, Guillaume; Tardif, Jean-Claude

    2017-01-01

    HDL cholesterol (HDL-C) remains a superior biochemical predictor of CVD risk, but its genetic basis is incompletely defined. In patients with extreme HDL-C concentrations, we concurrently evaluated the contributions of multiple large- and small-effect genetic variants. In a discovery cohort of 255 unrelated lipid clinic patients with extreme HDL-C levels, we used a targeted next-generation sequencing panel to evaluate rare variants in known HDL metabolism genes, simultaneously with common variants bundled into a polygenic trait score. Two additional cohorts were used for validation and included 1,746 individuals from the Montréal Heart Institute Biobank and 1,048 individuals from the University of Pennsylvania. Findings were consistent between cohorts: we found rare heterozygous large-effect variants in 18.7% and 10.9% of low- and high-HDL-C patients, respectively. We also found common variant accumulation, indicated by extreme polygenic trait scores, in an additional 12.8% and 19.3% of overall cases of low- and high-HDL-C extremes, respectively. Thus, the genetic basis of extreme HDL-C concentrations encountered clinically is frequently polygenic, with contributions from both rare large-effect and common small-effect variants. Multiple types of genetic variants should be considered as contributing factors in patients with extreme dyslipidemia. PMID:28870971

  1. High resolution spectroscopy of six new extreme helium stars

    Science.gov (United States)

    Heber, U.; Jones, G.; Drilling, J. S.

    1986-01-01

    High resolution spectra of six newly discovered extreme helium stars are presented. LSS 5121 is shown to be a spectroscopical twin of the hot extreme helium star HD 160641. A preliminary LTE analysis of LSS 3184 yielded an effective temperature of 22,000 K and a surface gravity of log g = 3.2. Four stars form a new subgroup, classified by sharp-lined He I spectra and pronounced O II spectra, and it is conjectured that these lie close to the Eddington limit. The whole group of extreme helium stars apparently is inhomogeneous with respect to luminosity to mass ratio and chemical composition.

  2. Extreme Conditioning Programs: Potential Benefits and Potential Risks.

    Science.gov (United States)

    Knapik, Joseph J

    2015-01-01

    CrossFit, Insanity, Gym Jones, and P90X are examples of extreme conditioning programs (ECPs). ECPs typically involve high-volume and high-intensity physical activities with short rest periods between movements and use of multiple joint exercises. Data on changes in fitness with ECPs are limited to CrossFit investigations that demonstrated improvements in muscle strength, muscular endurance, aerobic fitness, and body composition. However, no study has directly compared CrossFit or other ECPs to other more traditional forms of aerobic and resistance training within the same investigation. These direct comparisons are needed to more adequately evaluate the effectiveness of ECPs. Until these studies emerge, the comparisons with available literature suggest that improvements in CrossFit, in terms of muscular endurance (push-ups, sit-ups), strength, and aerobic capacity, appear to be similar to those seen in more traditional training programs. Investigations of injuries in ECPs are limited to two observational studies that suggest that the overall injury rate is similar to that seen in other exercise programs. Several cases of rhabdomyolysis and cervical carotid artery dissections have been reported during CrossFit training. The symptoms, diagnosis, and treatment of these are reviewed here. Until more data on ECPs emerge, physical training should be aligned with US Army doctrine. If ECPs are included in exercise programs, trainers should (1) have appropriate training certifications, (2) inspect exercise equipment regularly to assure safety, (3) introduce ECPs to new participants, (4) ensure medical clearance of Soldiers with special health problems before participation in ECPs, (4) tailor ECPs to the individual Soldier, (5) adjust rest periods to optimize recovery and reduce fatigue, (6) monitor Soldiers for signs of overtraining, rhabdomyolysis, and other problems, and (7) coordinate exercise programs with other unit training activities to eliminate redundant activities

  3. Workshop on extremely high energy density plasmas and their diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Shozo (ed.)

    2001-09-01

    Compiled are the papers presented at the workshop on 'Extremely High Energy Density Plasmas and Their Diagnostics' held at National Institute for Fusion Science. The papers cover physics and applications of extremely high-energy density plasmas such as dense z-pinch, plasma focus, and intense pulsed charged beams. Separate abstracts were presented for 7 of the papers in this report. The remaining 25 were considered outside the subject scope of INIS. (author)

  4. Workshop on extremely high energy density plasmas and their diagnostics

    International Nuclear Information System (INIS)

    Ishii, Shozo

    2001-09-01

    Compiled are the papers presented at the workshop on 'Extremely High Energy Density Plasmas and Their Diagnostics' held at National Institute for Fusion Science. The papers cover physics and applications of extremely high-energy density plasmas such as dense z-pinch, plasma focus, and intense pulsed charged beams. Separate abstracts were presented for 7 of the papers in this report. The remaining 25 were considered outside the subject scope of INIS. (author)

  5. Correlations in condensed matter under extreme conditions a tribute to Renato Pucci on the occasion of his 70th birthday

    CERN Document Server

    2017-01-01

    This book addresses a wide range of topics relating to the properties and behavior of condensed matter under extreme conditions such as intense magnetic and electric fields, high pressures, heat and cold, and mechanical stresses. It is divided into four sections devoted to condensed matter theory, molecular chemistry, theoretical physics, and the philosophy and history of science. The main themes include electronic correlations in material systems under extreme pressure and temperature conditions, surface physics, the transport properties of low-dimensional electronic systems, applications of the density functional theory in molecular systems, and graphene. The book is the outcome of a workshop held at the University of Catania, Italy, in honor of Professor Renato Pucci on the occasion of his 70th birthday. It includes selected invited contributions from collaborators and co-authors of Professor Pucci during his long and successful career, as well as from other distinguished guest authors.

  6. Extremely-high vacuum pressure measurement by laser ionization

    International Nuclear Information System (INIS)

    Kokubun, Kiyohide

    1991-01-01

    Laser ionization method has the very high sensitivity for detecting atoms and molecules. Hurst et al. successfully detected a single Cs atom by means of resonance ionization spectroscopy developed by them. Noting this high sensitivity, the authors have attempted to apply the laser ionization method to measure gas pressure, particularly in the range down to extremely high vacuum. At present, hot cathode ionization gauges are used for measuring gas pressure down to ultrahigh vacuum, however, those have a number of disadvantages. The pressure measurement using lasers does not have such disadvantages. The pressure measurement utilizing the laser ionization method is based on the principle that when laser beam is focused through a lens, the amount of atom or molecule ions generated in the focused space region is proportional to gas pressure. In this paper, the experimental results are presented on the nonresonant multiphoton ionization characteristics of various kinds of gases, the ion detection system with high sensitivity and an extremely high vacuum system prepared for the laser ionization experiment. (K.I.)

  7. Thermoregulatory value of cracking-clay soil shelters for small vertebrates during extreme desert conditions.

    Science.gov (United States)

    Waudby, Helen P; Petit, Sophie

    2017-05-01

    Deserts exhibit extreme climatic conditions. Small desert-dwelling vertebrates have physiological and behavioral adaptations to cope with these conditions, including the ability to seek shelter. We investigated the temperature (T) and relative humidity (RH) regulating properties of the soil cracks that characterize the extensive cracking-clay landscapes of arid Australia, and the extent of their use by 2 small marsupial species: fat-tailed and stripe-faced dunnarts (Sminthopsis crassicaudata and Sminthopsis macroura). We measured hourly (over 24-h periods) the T and RH of randomly-selected soil cracks compared to outside conditions, during 2 summers and 2 winters. We tracked 17 dunnarts (8 Sminthopsis crassicaudata and 9 Sminthopsis macroura) to quantify their use of cracks. Cracks consistently moderated microclimate, providing more stable conditions than available from non-crack points, which often displayed comparatively dramatic fluctuations in T and RH. Both dunnart species used crack shelters extensively. Cracks constitute important shelter for small animals during extreme conditions by providing a stable microclimate, which is typically cooler than outside conditions in summer and warmer in winter. Cracks likely play a fundamental sheltering role by sustaining the physiological needs of small mammal populations. Globally, cracking-clay areas are dominated by agricultural land uses, including livestock grazing. Management of these systems should focus not only on vegetation condition, but also on soil integrity, to maintain shelter resources for ground-dwelling fauna. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  8. Offshore wind turbine risk quantification/evaluation under extreme environmental conditions

    International Nuclear Information System (INIS)

    Taflanidis, Alexandros A.; Loukogeorgaki, Eva; Angelides, Demos C.

    2013-01-01

    A simulation-based framework is discussed in this paper for quantification/evaluation of risk and development of automated risk assessment tools, focusing on applications to offshore wind turbines under extreme environmental conditions. The framework is founded on a probabilistic characterization of the uncertainty in the models for the excitation, the turbine and its performance. Risk is then quantified as the expected value of some risk consequence measure over the probability distributions considered for the uncertain model parameters. Stochastic simulation is proposed for the risk assessment, corresponding to the evaluation of some associated probabilistic integral quantifying risk, as it allows for the adoption of comprehensive computational models for describing the dynamic turbine behavior. For improvement of the computational efficiency, a surrogate modeling approach is introduced based on moving least squares response surface approximations. The assessment is also extended to a probabilistic sensitivity analysis that identifies the importance of each of the uncertain model parameters, i.e. risk factors, towards the total risk as well as towards each of the failure modes contributing to this risk. The versatility and computational efficiency of the advocated approaches is finally exploited to support the development of standalone risk assessment applets for automated implementation of the probabilistic risk quantification/assessment. -- Highlights: ► A simulation-based risk quantification/assessment framework is discussed. ► Focus is on offshore wind turbines under extreme environmental conditions. ► Approach is founded on probabilistic description of excitation/system model parameters. ► Surrogate modeling is adopted for improved computational efficiency. ► Standalone risk assessment applets for automated implementation are supported

  9. Extremely high frequency RF effects on electronics.

    Energy Technology Data Exchange (ETDEWEB)

    Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

    2012-01-01

    The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

  10. Base Oil-Extreme Pressure Additive Synergy in Lubricants

    Science.gov (United States)

    Extreme pressure (EP) additives are those containing reactive elements such as sulfur, phosphorus, and chlorine. In lubrication processes that occur under extremely severe conditions (e.g., high pressure and/or slow speed), these elements undergo chemical reactions generating new materials (tribofi...

  11. Impacts of extreme weather events on highly eutrophic marine ecosystem (Rogoznica Lake, Adriatic coast)

    Science.gov (United States)

    Ciglenečki, I.; Janeković, I.; Marguš, M.; Bura-Nakić, E.; Carić, M.; Ljubešić, Z.; Batistić, M.; Hrustić, E.; Dupčić, I.; Garić, R.

    2015-10-01

    Rogoznica Lake is highly eutrophic marine system located on the Eastern Adriatic coast (43°32‧N, 15°58‧E). Because of the relatively small size (10,276 m2) and depth (15 m) it experiences strong natural and indirect anthropogenic influences. Dynamics within the lake is characterized by the extreme and highly variable environmental conditions (seasonal variations in salinity and temperature, water stratification and mixing, redox and euxinic conditions, concentrations of nutrients) which significantly influence the biology inside the lake. Due to the high phytoplankton activity, the upper part of the water column is well oxygenated, while hypoxia/anoxia usually occurs in the bottom layers. Anoxic part of the water column is characterized with high concentrations of sulfide (up to 5 mM) and nutrients (NH4+ up to 315 μM; PO43- up to 53 μM; SiO44- up to 680 μM) indicating the pronounced remineralization of the allochthonous organic matter, produced in the surface waters. The mixolimnion varies significantly within a season feeling effects of the Adriatic atmospheric and ocean dynamics (temperature, wind, heat fluxes, rainfall) which all affect the vertical stability and possibly induce vertical mixing and/or turnover. Seasonal vertical mixing usually occurs during the autumn/winter upon the breakdown of the stratification, injecting oxygen-rich water from the surface into the deeper layers. Depending on the intensity and duration of the vertical dynamics (slower diffusion and/or faster turnover of the water layers) anoxic conditions could developed within the whole water column. Extreme weather events such as abrupt change in the air temperature accompanied with a strong wind and consequently heat flux are found to be a key triggering mechanism for the fast turnover, introducing a large amount of nutrients and sulfur species from deeper parts to the surface. Increased concentration of nutrients, especially ammonium, phosphate, and silicates persisting for

  12. [Injury mechanisms in extreme violence settings].

    Science.gov (United States)

    Arcaute-Velazquez, Fernando Federico; García-Núñez, Luis Manuel; Noyola-Vilallobos, Héctor Faustino; Espinoza-Mercado, Fernando; Rodríguez-Vega, Carlos Eynar

    2016-01-01

    Extreme violence events are consequence of current world-wide economic, political and social conditions. Injury patterns found among victims of extreme violence events are very complex, obeying several high-energy injury mechanisms. In this article, we present the basic concepts of trauma kinematics that regulate the clinical approach to victims of extreme violence events, in the hope that clinicians increase their theoretical armamentarium, and reflecting on obtaining better outcomes. Copyright © 2016. Published by Masson Doyma México S.A.

  13. Bridge Management Strategy Based on Extreme User Costs for Bridge Network Condition

    Directory of Open Access Journals (Sweden)

    Ladislaus Lwambuka

    2014-01-01

    Full Text Available This paper presents a practical approach for prioritization of bridge maintenance within a given bridge network. The maintenance prioritization is formulated as a multiobjective optimization problem where the simultaneous satisfaction of several conflicting objectives includes minimization of maintenance costs, maximization of bridge deck condition, and minimization of traffic disruption and associated user costs. The prevalence of user cost during maintenance period is twofold; the first case refers to the period of dry season where normally the traffic flow is diverted to alternative routes usually resurfaced to regain traffic access. The second prevalence refers to the absence of alternative routes which is often the case in the least developed countries; in this case the user cost referred to results from the waiting time while the traffic flow is put on hold awaiting accomplishment of the maintenance activity. This paper deals with the second scenario of traffic closure in the absence of alternative diversion routes which in essence results in extreme user cost. The paper shows that the multiobjective optimization approach remains valid for extreme cases of user costs in the absence of detour roads as often is the scenario in countries with extreme poor road infrastructure.

  14. Aortic dissection: natural course of disease? Report of two cases representing the extremes of the condition

    International Nuclear Information System (INIS)

    Tollefsen, Isak; Joergensen, Ingrid K.; Woie, Leik; Fossdal, Jan E.

    2001-01-01

    Objective: In a time when diagnostic methods and above all, surgical as well as interventional radiological treatment for aortic aneurysms and aortic dissections have reached a point nobody could think of a few years back, the present authors feel that it is worth while to remind oneself of the natural course of disease in these conditions. Taking into consideration the high morbidity and mortality rate in surgically treated patients with aortic dissection, and the high complication rate per- and postoperatively, it also seems right to ask if a more expectative and conservative approach to the condition sometimes perhaps may be justified. Methods and material: Two case reports are given. One was a 15-year-old boy with Stanford (Daily) type B dissection who statistically ought to have a good prognosis, but who died within 2 h after onset of symptoms. The other patient, a middle-aged woman with Stanford type A dissection, survived for 25 years without operation. Conclusion: These two cases, though not unique viewed separately, we consider to represent the extremes of the condition and also a natural course of disease, while none of them was operated on

  15. Aortic dissection: natural course of disease? Report of two cases representing the extremes of the condition.

    Science.gov (United States)

    Tollefsen, I; Jørgensen, I K; Woie, L; Fossdal, J E

    2001-10-01

    In a time when diagnostic methods and above all, surgical as well as interventional radiological treatment for aortic aneurysms and aortic dissections have reached a point nobody could think of a few years back, the present authors feel that it is worth while to remind oneself of the natural course of disease in these conditions. Taking into consideration the high morbidity and mortality rate in surgically treated patients with aortic dissection, and the high complication rate per- and postoperatively, it also seems right to ask if a more expectative and conservative approach to the condition sometimes perhaps may be justified. Two case reports are given. One was a 15-year-old boy with Stanford (Daily) type B dissection who statistically ought to have a good prognosis, but who died within 2 h after onset of symptoms. The other patient, a middle-aged woman with Stanford type A dissection, survived for 25 years without operation. These two cases, though not unique viewed separately, we consider to represent the extremes of the condition and also a natural course of disease, while none of them was operated on.

  16. Extreme wind conditions for a Danish offshore site

    DEFF Research Database (Denmark)

    Hansen, Kurt S.

    2000-01-01

    This paper presents an analysis of extreme wind speed gust values measured at a shallow water offshore site and at a coastal onshore site in Denmark. An estimate of 50-year extreme values has been evaluated using a new statistical method. In addition a mean gust shape is determined, based on a la...

  17. Development and performance test of a system available for generating multiple extreme conditions for neutron scattering experiments

    International Nuclear Information System (INIS)

    Kawano, Shinji; Fukui, Susumu; Moriai, Atsushi; Ohtomo, Akitoshi; Ichimura, Shigeki; Onodera, Akifumi; Amita, F.; Katano, Susumu

    1998-01-01

    We have developed unique system available for controlling sample environment during the neutron scattering experiments. The system can simultaneously generate triple extreme conditions of low temperature, high magnetic field and high pressure. The system consists of: (i) a liquid-helium cryostat variable for sample temperature from 1.7 K to 200 K, (ii) a superconducting magnet providing a vertical field up to ±5 T with an antisymmetric split-coil geometry for polarized-beam experiments, and (iii) a non-magnetic piston-cylinder high-pressure cell designed with the aim of generating hydrostatic pressure up to 2.5 GPa. In the presentation, we will report the outline of the system and some results of performance tests at KURRI and JRR-3M of JAERI. (author)

  18. Development of a high-resolution apparatus to monitor physiological state of a person undergoing extreme conditions

    Directory of Open Access Journals (Sweden)

    Kodermyatov Radik

    2016-01-01

    Full Text Available The present research has shown that ECG recordings and parameters of the body functional state are crucial for all kinds of the astronaut pre-flight preparations (centrifuge, thermal chamber, pressure chamber, pressure chamber with special equipment. It is, therefore, important to develop methods and tools for early detection of the preclinical forms of the functional state disorders in patients undergoing high-intensity loads of mixed character. The method based on the hardware-software compleх (HSC with nanosensors of high resolution has been proposed to measure the electrophysiological characteristics and bioelectrical impedance of the body tissues directly exposed to loading. The hardware-software compleх is subjected to clinical trials in Tomsk Research Institute for Cardiology. The obtained results show that the use of nanosensors of high resolution in the HSC without standard filters allows elimination of the power-line interference in ECG recordings. Monitoring of the tissue bioimpedance parameters under test loads enables the detection of preclinical (latent forms of various diseases. After clinical trials in Tomsk Institute for Cardiology the developed apparatus will be proposed for in-depth study of the cardiovascular system and the functional state of the body of astronauts and other persons exposed to extreme loads.

  19. Investigating the Effects of Simulated Space conditions on Novel Extremely Halophilic Archaea: Halovarius Luteus gen. nov., sp. nov.

    Science.gov (United States)

    Feshangsaz, Niloofar; Van Loon, ing.. Jack J. W. A.; Nazmi, Kamran; Semsarha, Farid

    2016-07-01

    Studying halophiles from different environments of Earth provide new insights into our search for life in the universe. Haloarchaea show some unique characteristics and physiological adaptations like acidic proteins against harsh environments such as natural brine with salt concentration approaching saturation (5 M) and regions with low active water. These properties make haloarchaea interesting candidate for astrobiological studies. Halovarius luteus gen. nov., sp. nov. a novel extremely halophilic archaeon from Urmia salt lake, in Iran has been chosen to explore its resistance against a series of extreme conditions. The aim of this study is to assess the resistance of strain DA50T under the effects of simulated space conditions like simulated microgravity, hypergravity, and desiccation. In this paper we will discuss the results of these studies where we specifically focus on changes in carotenoid pigments production and whole cell proteome. This is the first report of very novel Iranian archaea in response to extreme space conditions. The pigments were extracted by acetone and methanol. Pigments were analyzed by scanning the absorbance spectrum in the UV-VIS spectrophotometer. And they were separated by TLC. Whole protein from cell lysate supernatant was extracted after lysis with Bacterial Protein Extraction Reagent and fractionated by RP-HPLC using C18 column. Proteome analyzed by electrophoresis (SDS-PAGE), and MALDI-TOF. Carotenoid pigments are formed under different extreme conditions such as dry environment and gravitational changes. Also the protein composition exhibits alterations after exposure to the same conditions. Our conclusion is that pigments and proteins formation depend on the growth circumstances. Halophiles use this as an adaptation to survive under different environmental conditions.

  20. The evolution of extreme precipitations in high resolution scenarios over France

    Science.gov (United States)

    Colin, J.; Déqué, M.; Somot, S.

    2009-09-01

    Over the past years, improving the modelling of extreme events and their variability at climatic time scales has become one of the challenging issue raised in the regional climate research field. This study shows the results of a high resolution (12 km) scenario run over France with the limited area model (LAM) ALADIN-Climat, regarding the representation of extreme precipitations. The runs were conducted in the framework of the ANR-SCAMPEI national project on high resolution scenarios over French mountains. As a first step, we attempt to quantify one of the uncertainties implied by the use of LAM : the size of the area on which the model is run. In particular, we address the issue of whether a relatively small domain allows the model to create its small scale process. Indeed, high resolution scenarios cannot be run on large domains because of the computation time. Therefore one needs to answer this preliminary question before producing and analyzing such scenarios. To do so, we worked in the framework of a « big brother » experiment. We performed a 23-year long global simulation in present-day climate (1979-2001) with the ARPEGE-Climat GCM, at a resolution of approximately 50 km over Europe (stretched grid). This first simulation, named ARP50, constitutes the « big brother » reference of our experiment. It has been validated in comparison with the CRU climatology. Then we filtered the short waves (up to 200 km) from ARP50 in order to obtain the equivalent of coarse resolution lateral boundary conditions (LBC). We have carried out three ALADIN-Climat simulations at a 50 km resolution with these LBC, using different configurations of the model : * FRA50, run over a small domain (2000 x 2000 km, centered over France), * EUR50, run over a larger domain (5000 x 5000 km, centered over France as well), * EUR50-SN, run over the large domain (using spectral nudging). Considering the facts that ARPEGE-Climat and ALADIN-Climat models share the same physics and dynamics

  1. Wave-mixing with high-order harmonics in extreme ultraviolet region

    International Nuclear Information System (INIS)

    Dao, Lap Van; Dinh, Khuong Ba; Le, Hoang Vu; Gaffney, Naylyn; Hannaford, Peter

    2015-01-01

    We report studies of the wave-mixing process in the extreme ultraviolet region with two near-infrared driving and controlling pulses with incommensurate frequencies (at 1400 nm and 800 nm). A non-collinear scheme for the two beams is used in order to spatially separate and to characterise the properties of the high-order wave-mixing field. We show that the extreme ultraviolet frequency mixing can be treated by perturbative, very high-order nonlinear optics; the modification of the wave-packet of the free electron needs to be considered in this process

  2. Investigating Extreme Lifestyles through Mangrove Transcriptomics

    Science.gov (United States)

    Dassanayake, Maheshi

    2009-01-01

    Mangroves represent phylogenetically diverse taxa in tropical coastal terrestrial habitats. They are extremophiles, evolutionarily adapted to tolerate flooding, anoxia, high temperatures, wind, and high and extremely variable salt conditions in typically resource-poor environments. The genetic basis for these adaptations is, however, virtually…

  3. Identification of Extreme Events Under Climate Change Conditions Over Europe and The Northwest-atlantic Region: Spatial Patterns and Time Series Characteristics

    Science.gov (United States)

    Leckebusch, G.; Ulbrich, U.; Speth, P.

    In the context of climate change and the resulting possible impacts on socio-economic conditions for human activities it seems that due to a changed occurrence of extreme events more severe consequences have to be expected than from changes in the mean climate. These extreme events like floods, excessive heats and droughts or windstorms possess impacts on human social and economic life in different categories such as forestry, agriculture, energy use, tourism and the reinsurance business. Reinsurances are affected by nearly 70% of all insured damages over Europe in the case of wind- storms. Especially the December 1999 French windstorms caused damages about 10 billion. A new EU-founded project (MICE = Modelling the Impact of Climate Ex- tremes) will focus on these impacts caused by changed occurrences of extreme events over Europe. Based upon the output of general circulation models as well as regional climate models, investigations are carried out with regard to time series characteristics as well as the spatial patterns of extremes under climate changed conditions. After the definition of specific thresholds for climate extremes, in this talk we will focus on the results of the analysis for the different data sets (HadCM3 and CGCMII GCM's and RCM's, re-analyses, observations) with regard to windstorm events. At first the results of model outputs are validated against re-analyses and observations. Especially a comparison of the stormtrack (2.5 to 8 day bandpass filtered 500 hPa geopotential height), cyclone track, cyclone frequency and intensity is presented. Highly relevant to damages is the extreme wind near the ground level, so the 10 m wind speed will be investigated additionally. of special interest to possible impacts is the changed spatial occurrence of windspeed maxima under 2xCO2-induced climate change.

  4. Safety analysis of casks under extreme impact conditions

    International Nuclear Information System (INIS)

    Wieser, G.; Qiao, L.; Voelzke, H.; Wolff, D.; Droste, B.

    2004-01-01

    The determination of the inherent safety of casks under extreme impact conditions has been of increasing interest since the terrorist attacks of 11 September 2001. For nearly three decades BAM has been investigating cask safety under severe accident conditions like drop tests from more than 9 m onto different targets and without impact limiters as well as artificially damaged prototype casks. One of the most critical scenarios for a cask is the centric impact of a dynamic load onto the lid-seal system. This can be caused, for example, by a direct aircraft crash (or just its engine) as well as by an impact due to the collapse of a building, e.g. a nuclear facility storage hall. In this context BAM is developing methods to calculate the deformation of cask components and-with respect to leak-tightness-relative displacements between the metallic seals and their counterparts. This paper presents reflections on modelling of cask structures for finite-element analyses and discusses calculated results of stresses and deformations. Another important aspect is the behaviour of a cask under a lateral impact by aircraft or fragments of a building. Examples of the kinetic reaction (cask acceleration due to the fragments, subsequent contact with neighbouring structures like the ground, buildings or casks) are shown and discussed in correlation to cask stresses which are to be expected. (author)

  5. Safety analysis of casks under extreme impact conditions

    International Nuclear Information System (INIS)

    Wieser, G.; Qiao Linan; Voelzke, H.; Wolff, D.; Droste, B.

    2004-01-01

    The determination of the inherent safety of casks also under extreme impact conditions has been of increasing interest since the terrorist attacks from 11th September 2001. For nearly three decades BAM has been investigating cask safety under severe accident conditions like drop tests from more than 9 m onto different targets and without impact limiters as well as artificially damaged prototype casks. One of the most critical scenarios for a cask is the centric impact of a dynamic load onto the lid seal system. This can be caused e.g. by direct aircraft crash or its engine as well as by an impact due to the collapse of a building e.g. a nuclear facility storage hall. In this context BAM is developing methods to calculate the deformation of cask components and - with respect to leak tightness - relative displacements between the metallic seals and their counterparts. This paper presents reflections on modelling of cask structures for Finite Element analyses and discusses calculated results of stresses and deformations. Another important aspect is the behaviour of a cask under a lateral impact by aircraft and fragments of a building. Examples of the kinetic reaction (cask acceleration due to the fragments, subsequent contact with neighbouring structures like ground, buildings or casks) are shown and discussed in correlation to cask stresses which are to be expected

  6. Normal and Extreme Wind Conditions for Power at Coastal Locations in China.

    Science.gov (United States)

    Gao, Meng; Ning, Jicai; Wu, Xiaoqing

    2015-01-01

    In this paper, the normal and extreme wind conditions for power at 12 coastal locations along China's coastline were investigated. For this purpose, the daily meteorological data measured at the standard 10-m height above ground for periods of 40-62 years are statistically analyzed. The East Asian Monsoon that affects almost China's entire coastal region is considered as the leading factor determining wind energy resources. For most stations, the mean wind speed is higher in winter and lower in summer. Meanwhile, the wind direction analysis indicates that the prevalent winds in summer are southerly, while those in winter are northerly. The air densities at different coastal locations differ significantly, resulting in the difference in wind power density. The Weibull and lognormal distributions are applied to fit the yearly wind speeds. The lognormal distribution performs better than the Weibull distribution at 8 coastal stations according to two judgement criteria, the Kolmogorov-Smirnov test and absolute error (AE). Regarding the annual maximum extreme wind speed, the generalized extreme value (GEV) distribution performs better than the commonly-used Gumbel distribution. At these southeastern coastal locations, strong winds usually occur in typhoon season. These 4 coastal provinces, that is, Guangdong, Fujian, Hainan, and Zhejiang, which have abundant wind resources, are also prone to typhoon disasters.

  7. Single-crystal diffraction at the Extreme Conditions beamline P02.2: procedure for collecting and analyzing high-pressure single-crystal data.

    Science.gov (United States)

    Rothkirch, André; Gatta, G Diego; Meyer, Mathias; Merkel, Sébastien; Merlini, Marco; Liermann, Hanns Peter

    2013-09-01

    Fast detectors employed at third-generation synchrotrons have reduced collection times significantly and require the optimization of commercial as well as customized software packages for data reduction and analysis. In this paper a procedure to collect, process and analyze single-crystal data sets collected at high pressure at the Extreme Conditions beamline (P02.2) at PETRA III, DESY, is presented. A new data image format called `Esperanto' is introduced that is supported by the commercial software package CrysAlis(Pro) (Agilent Technologies UK Ltd). The new format acts as a vehicle to transform the most common area-detector data formats via a translator software. Such a conversion tool has been developed and converts tiff data collected on a Perkin Elmer detector, as well as data collected on a MAR345/555, to be imported into the CrysAlis(Pro) software. In order to demonstrate the validity of the new approach, a complete structure refinement of boron-mullite (Al5BO9) collected at a pressure of 19.4 (2) GPa is presented. Details pertaining to the data collections and refinements of B-mullite are presented.

  8. Taking water-based mud to extremes : new ultra-high temperature water-based mud development and applications in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Conn, L.; Cullum, D.; Ray, R.; Marinescu, P. [Mi SWACO, Calgary, AB (Canada)

    2008-07-01

    The design, development and field applications of an ultra-high temperature water-based mud used for drilling very deep and hot wells in continental Europe was described. Basin-centred gas production from unconventional tight sands represents a significant resources that may revive exploration and gas production. However, these accumulations lie deep down from normal-pressure reservoirs and the bottom hole static temperatures are greater than 200 degrees C. In addition, they host acid gases such as carbon dioxide and hydrogen sulfide. As such, there are severe limitations on the design and choice of drilling fluids. This paper also described the extensive laboratory work that is needed to optimize the formulation of drilling fluids for high densities and extreme high temperatures. The lessons learned were described with reference to critical engineering guidelines for running a water-based system in such harsh conditions. The effectiveness of new fluids in delivering optimum drilling in extreme high temperature high pressure (HTHP) conditions were demonstrated using a unique software program that predicted the rheological behaviour, pressure losses, equivalent circulating density and equivalent static density. The new water-based system proved to be effective in drilling HTHP wells in areas where invert emulsion drilling fluid systems are not allowed.

  9. Operational early warning platform for extreme meteorological events

    Science.gov (United States)

    Mühr, Bernhard; Kunz, Michael

    2015-04-01

    Operational early warning platform for extreme meteorological events Most natural disasters are related to extreme weather events (e.g. typhoons); weather conditions, however, are also highly relevant for humanitarian and disaster relief operations during and after other natural disaster like earthquakes. The internet service "Wettergefahren-Frühwarnung" (WF) provides various information on extreme weather events, especially when these events are associated with a high potential for large damage. The main focus of the platform is on Central Europe, but major events are also monitored worldwide on a daily routine. WF provides high-resolution forecast maps for many weather parameters which allow detailed and reliable predictions about weather conditions during the next days in the affected areas. The WF service became operational in February 2004 and is part of the Center for Disaster Management and Risk Reduction Technology (CEDIM) since 2007. At the end of 2011, CEDIM embarked a new type of interdisciplinary disaster research termed as forensic disaster analysis (FDA) in near real time. In case of an imminent extreme weather event WF plays an important role in CEDIM's FDA group. It provides early and precise information which are always available and updated several times during a day and gives advice and assists with articles and reports on extreme events.

  10. Is Extremely High Life Satisfaction during Adolescence Advantageous?

    Science.gov (United States)

    Suldo, Shannon M.; Huebner, E. Scott

    2006-01-01

    This study examined whether extremely high life satisfaction was associated with adaptive functioning or maladaptive functioning. Six hundred ninety-eight secondary level students completed the Students' Life Satisfaction Scale [Huebner, 1991a, School Psychology International, 12, pp. 231-240], Youth Self-Report of the Child Behavior Checklist…

  11. Statistical Model of Extreme Shear

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Hansen, Kurt Schaldemose

    2004-01-01

    In order to continue cost-optimisation of modern large wind turbines, it is important to continously increase the knowledge on wind field parameters relevant to design loads. This paper presents a general statistical model that offers site-specific prediction of the probability density function...... by a model that, on a statistically consistent basis, describe the most likely spatial shape of an extreme wind shear event. Predictions from the model have been compared with results from an extreme value data analysis, based on a large number of high-sampled full-scale time series measurements...... are consistent, given the inevitabel uncertainties associated with model as well as with the extreme value data analysis. Keywords: Statistical model, extreme wind conditions, statistical analysis, turbulence, wind loading, statistical analysis, turbulence, wind loading, wind shear, wind turbines....

  12. Expert consensus on facilitators and barriers to return-to-work following surgery for non-traumatic upper extremity conditions: a Delphi study.

    Science.gov (United States)

    Peters, S E; Johnston, V; Ross, M; Coppieters, M W

    2017-02-01

    This Delphi study aimed to reach consensus on important facilitators and barriers for return-to-work following surgery for non-traumatic upper extremity conditions. In Round 1, experts ( n = 42) listed 134 factors, which were appraised in Rounds 2 and 3. Consensus (⩾85% agreement) was achieved for 13 facilitators (high motivation to return-to-work; high self-efficacy for return-to-work and recovery; availability of modified/alternative duties; flexible return-to-work arrangements; positive coping skills; limited heavy work exertion; supportive return-to-work policies; supportive supervisor/management; no catastrophic thinking; no fear avoidance to return-to-work; no fear avoidance to pain/activity; return to meaningful work duties; high job satisfaction) and six barriers (mood disorder diagnosis; pain/symptoms at more than one musculoskeletal site; heavy upper extremity exertions at work; lack of flexible return-to-work arrangements; lack of support from supervisor/management; high level of pain catastrophizing). Future prognostic studies are required to validate these biopsychosocial factors to further improve return-to-work outcomes. V.

  13. An archaeal tRNA-synthetase complex that enhances aminoacylation under extreme conditions

    DEFF Research Database (Denmark)

    Godinic-Mikulcic, Vlatka; Jaric, Jelena; Hausmann, Corinne D

    2011-01-01

    Aminoacyl-tRNA synthetases (aaRSs) play an integral role in protein synthesis, functioning to attach the correct amino acid with its cognate tRNA molecule. AaRSs are known to associate into higher-order multi-aminoacyl-tRNA synthetase complexes (MSC) involved in archaeal and eukaryotic translatio...... of a complex between MtSerRS and MtArgRS provides a means by which methanogenic archaea can optimize an early step in translation under a wide range of extreme environmental conditions....

  14. Matter Under Extreme Conditions: The Early Years

    Science.gov (United States)

    Keeler, R. Norris; Gibson, Carl H.

    2012-03-01

    Extreme conditions in natural flows are examined, starting with a turbulent big bang. A hydro-gravitational-dynamics cosmology model is adopted. Planck-Kerr turbulence instability causes Planck-particle turbulent combustion. Inertial-vortex forces induce a non-turbulent ki- netic energy cascade to Planck-Kolmogorov scales where vorticity is produced, overcoming 10113 Pa Planck-Fortov pressures. The spinning, expanding fireball has a slight deficit of Planck antiparticles. Space and mass-energy powered by gluon viscous stresses expand exponentially at speeds >1025 c. Turbulent temperature and spin fluctuations fossilize at scales larger than ct, where c is light speed and t is time. Because "dark-energy" antigravity forces vanish when infla- tion ceases, and because turbulence produces entropy, the universe is closed and will collapse and rebound. Density and spin fossils of big bang turbulent mixing trigger structure formation in the plasma epoch. Fragmenting protosuperclustervoids and protoclustervoids produce weak tur- bulence until the plasma-gas transition give chains of protogalaxies with the morphology of tur- bulence. Chain galaxy clusters observed at large redshifts ~8.6 support this interpretation. Pro- togalaxies fragment into clumps, each with a trillion Earth-mass H-He gas planets. These make stars, supernovae, the first chemicals, the first oceans and the first life soon after the cosmologi- cal event.

  15. Regional-Scale High-Latitude Extreme Geoelectric Fields Pertaining to Geomagnetically Induced Currents

    Science.gov (United States)

    Pulkkinen, Antti; Bernabeu, Emanuel; Eichner, Jan; Viljanen, Ari; Ngwira, Chigomezyo

    2015-01-01

    Motivated by the needs of the high-voltage power transmission industry, we use data from the high-latitude IMAGE magnetometer array to study characteristics of extreme geoelectric fields at regional scales. We use 10-s resolution data for years 1993-2013, and the fields are characterized using average horizontal geoelectric field amplitudes taken over station groups that span about 500-km distance. We show that geoelectric field structures associated with localized extremes at single stations can be greatly different from structures associated with regionally uniform geoelectric fields, which are well represented by spatial averages over single stations. Visual extrapolation and rigorous extreme value analysis of spatially averaged fields indicate that the expected range for 1-in-100-year extreme events are 3-8 V/km and 3.4-7.1 V/km, respectively. The Quebec reference ground model is used in the calculations.

  16. Enhancing protein to extremely high content in photosynthetic bacteria during biogas slurry treatment.

    Science.gov (United States)

    Yang, Anqi; Zhang, Guangming; Meng, Fan; Lu, Pei; Wang, Xintian; Peng, Meng

    2017-12-01

    This work proposed a novel approach to achieve an extremely high protein content in photosynthetic bacteria (PSB) using biogas slurry as a culturing medium. The results showed the protein content of PSB could be enhanced strongly to 90% in the biogas slurry, which was much higher than reported microbial protein contents. The slurry was partially purified at the same time. Dark-aerobic was more beneficial than light-anaerobic condition for protein accumulation. High salinity and high ammonia of the biogas slurry were the main causes for protein enhancement. In addition, the biogas slurry provided a good buffer system for PSB to grow. The biosynthesis mechanism of protein in PSB was explored according to theoretical analysis. During biogas slurry treatment, the activities of glutamate synthase and glutamine synthetase were increased by 26.55%, 46.95% respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Properties of a planar electric double layer under extreme conditions investigated by classical density functional theory and Monte Carlo simulations.

    Science.gov (United States)

    Zhou, Shiqi; Lamperski, Stanisław; Zydorczak, Maria

    2014-08-14

    Monte Carlo (MC) simulation and classical density functional theory (DFT) results are reported for the structural and electrostatic properties of a planar electric double layer containing ions having highly asymmetric diameters or valencies under extreme concentration condition. In the applied DFT, for the excess free energy contribution due to the hard sphere repulsion, a recently elaborated extended form of the fundamental measure functional is used, and coupling of Coulombic and short range hard-sphere repulsion is described by a traditional second-order functional perturbation expansion approximation. Comparison between the MC and DFT results indicates that validity interval of the traditional DFT approximation expands to high ion valences running up to 3 and size asymmetry high up to diameter ratio of 4 whether the high valence ions or the large size ion are co- or counter-ions; and to a high bulk electrolyte concentration being close to the upper limit of the electrolyte mole concentration the MC simulation can deal with well. The DFT accuracy dependence on the ion parameters can be self-consistently explained using arguments of liquid state theory, and new EDL phenomena such as overscreening effect due to monovalent counter-ions, extreme layering effect of counter-ions, and appearance of a depletion layer with almost no counter- and co-ions are observed.

  18. Fabrication of Diamond Based Sensors for Use in Extreme Environments

    Directory of Open Access Journals (Sweden)

    Gopi K. Samudrala

    2015-04-01

    Full Text Available Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This method can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. We demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.

  19. High-resolution Sonographic Measurements of Lower Extremity Bursae in Chinese Healthy Young Men

    Directory of Open Access Journals (Sweden)

    Yong-Yan Gao

    2016-01-01

    Conclusions: Using HR-US imaging, we were able to analyze lower extremity bursae with high detection rates in healthy young men. The normal ranges of lower extremity bursa dimensions in healthy young men measured by HR-US in this study could be used as reference values for evaluation of bursa abnormalities in the lower extremity.

  20. Extremely high thermal conductivity anisotropy of double-walled carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Zhaoji Ma

    2017-06-01

    Full Text Available Based on molecular dynamics simulations, we reveal that double-walled carbon nanotubes can possess an extremely high anisotropy ratio of radial to axial thermal conductivities. The mechanism is basically the same as that for the high thermal conductivity anisotropy of graphene layers - the in-plane strong sp2 bonds lead to a very high intralayer thermal conductivity while the weak van der Waals interactions to a very low interlayer thermal conductivity. However, different from flat graphene layers, the tubular structures of carbon nanotubes result in a diameter dependent thermal conductivity. The smaller the diameter, the larger the axial thermal conductivity but the smaller the radial thermal conductivity. As a result, a DWCNT with a small diameter may have an anisotropy ratio of thermal conductivity significantly higher than that for graphene layers. The extremely high thermal conductivity anisotropy allows DWCNTs to be a promising candidate for thermal management materials.

  1. State-of-the-Art of Extreme Pressure Lubrication Realized with the High Thermal Diffusivity of Liquid Metal.

    Science.gov (United States)

    Li, Haijiang; Tian, Pengyi; Lu, Hongyu; Jia, Wenpeng; Du, Haodong; Zhang, Xiangjun; Li, Qunyang; Tian, Yu

    2017-02-15

    Sliding between two objects under very high load generally involves direct solid-solid contact at molecular/atomic level, the mechanism of which is far from clearly disclosed yet. Those microscopic solid-solid contacts could easily lead to local melting of rough surfaces. At extreme conditions, this local melting could propagate to the seizure and welding of the entire interface. Traditionally, the microscopic solid-solid contact is alleviated by various lubricants and additives based on their improved mechanical properties. In this work, we realized the state-of-the-art of extreme pressure lubrication by utilizing the high thermal diffusivity of liquid metal, 2 orders of magnitude higher than general organic lubricants. The extreme pressure lubrication property of gallium based liquid metal (GBLM) was compared with gear oil and poly-α-olefin in a four-ball test. The liquid metal lubricates very well at an extremely high load (10 kN, the maximum capability of a four-ball tester) at a rotation speed of 1800 rpm for a duration of several minutes, much better than traditional organic lubricants which typically break down within seconds at a load of a few kN. Our comparative experiments and analysis showed that this superextreme pressure lubrication capability of GBLM was attributed to the synergetic effect of the ultrafast heat dissipation of GBLM and the low friction coefficient of FeGa 3 tribo-film. The present work demonstrated a novel way of improving lubrication capability by enhancing the lubricant thermal properties, which might lead to mechanical systems with much higher reliability.

  2. Extreme Wave-Induced Oscillation in Paradip Port Under the Resonance Conditions

    Science.gov (United States)

    Kumar, Prashant; Gulshan

    2017-12-01

    A mathematical model is constructed to analyze the long wave-induced oscillation in Paradip Port, Odisha, India under the resonance conditions to avert any extreme wave hazards. Boundary element method (BEM) with corner contribution is utilized to solve the Helmholtz equation under the partial reflection boundary conditions. Furthermore, convergence analysis is also performed for the boundary element scheme with uniform and non-uniform discretization of the boundary. The numerical scheme is also validated with analytic approximation and existing studies based on harbor resonance. Then, the amplification factor is estimated at six key record stations in the Paradip Port with multidirectional incident waves and resonance modes are also estimated at the boundary of the port. Ocean surface wave field is predicted in the interior of Paradip Port for the different directional incident wave at various resonance modes. Moreover, the safe locations in the port have been identified for loading and unloading of moored ship with different resonance modes and directional incident waves.

  3. Extreme Consumption Drinking Gaming and Prepartying among High School Students

    Science.gov (United States)

    Tomaso, Cara C.; Zamboanga, Byron L.; Haas, Amie L.; Kenney, Shannon R.; Ham, Lindsay S.; Borsari, Brian

    2016-01-01

    Drinking games and prepartying (i.e., drinking before going to a social gathering/event) have emerged as high-risk drinking behaviors in high school students. The present study examines the current prepartying behaviors of high school students who report current participation in extreme-consumption games (e.g., chugging) with those who do not.…

  4. Influence of Extreme Storage Conditions on Extra Virgin Olive Oil Parameters: Traceability Study

    Directory of Open Access Journals (Sweden)

    Alfredo Escudero

    2016-01-01

    Full Text Available This study reflects the effect of extreme storage conditions on several extra virgin olive oil (EVOO varieties (arbequina, hojiblanca, and picual. The conditions were simulated in the laboratory, by means of heating treatments in stove at different temperatures (40 and 60°C and times (two and three weeks. The aim is the evaluation of the deterioration of the quality parameters and minority components, which are responsible for the nutritional and therapeutic properties (fatty acids, polyphenols, pigments, and tocopherols, and organoleptic qualities. The quality criteria and limits used in this work are according to International Olive Council. The results contribute to the control of the traSceability for the commercialization of the EVOO.

  5. HERCULES Specialized Course on Synchrotron radiation and neutrons for extreme conditions studies - HSC12 - slides of the presentations

    International Nuclear Information System (INIS)

    Daniel, I.; Itie, J.P.; Meersman, F.; Jacobs, J.; Hantsetters, K. de; Syassen, K.; Krisch, M.; Mezouar, M.; Mac Millan, P.F.; Salmon, P.; Klotz, S.; Pascarelli, S.; Hansen, T.C.

    2011-01-01

    The purpose of this Hercules Specialized Course (HSC12) is to give the participants an introduction to high pressure research at large experimental facilities such as the synchrotron and the neutron reactor. The basic principles of synchrotron radiation and neutrons techniques at extreme conditions of pressure have been illustrated. Cross-disciplinary examples in a representative range of scientific areas, covering fundamental physics, earth and planetary science, chemistry and material science have been dealt with. Most presentations are dedicated to X-ray diffraction, X-ray absorption and neutron scattering of materials (solids, liquids or glasses) at high pressure. Several presentations deal with the experimental set-up and especially the preparation of the diamond anvil. This document is made up of the slides of the presentations. (A.C.)

  6. Exertional Rhabdomyolysis after an Extreme Conditioning Competition: A Case Report

    Directory of Open Access Journals (Sweden)

    Ramires Alsamir Tibana

    2018-04-01

    Full Text Available This case report describes an instance of exercise-induced rhabdomyolysis caused by an extreme conditioning program (ECP competition. A 35-year-old female presented with abdominal pain and soreness, which began one day after she completed two days of ECPcompetition composed of five workouts. Three days after competition, creatine kinase (CK was 77,590 U/L accompanied by myalgia and abnormal liver function tests, while renal function was normal and this resulted in a diagnosis of rhabdomyolysis. A follow-up examination revealed that her serum level of CK was still elevated to 3034 U/L on day 10 and 1257 U/L on day 25 following the ECP competition. The subject reported myalgia even up to 25 days after the ECP competition. Exertional rhabdomyolysis can be observed in ECP athletes following competition and highlights a dangerous condition, which may be increasing in recent years due to the massive expansion of ECP popularity and a growing number of competitions. Future research should investigate the causes of rhabdomyolysis that occur as a result of ECP, especially training methods and/or tasks developed specifically for these competitions.

  7. Final Report for Project. Quark matter under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Incera, Vivian [Univ. of Texas, El Paso, TX (United States); Ferrer, Efrain [Univ. of Texas, El Paso, TX (United States)

    2015-12-31

    The results obtained in the two years of the grant have served to shine new light on several important questions about the phases of quantum chromodynamics (QCD) under extreme conditions that include quark matter at high density, as well quark-gluon plasma at high temperatures, both in the presence of strong magnetic fields. The interest in including an external magnetic field on these studies is motivated by the generation of large magnetic fields in off-central heavy-ion collisions and by their common presence in astrophysical compact objects, the two scenarios where the physics of quark matter becomes relevant. The tasks carried out in this DOE project led us, among other things, to discover the first connection between the physics of very dense quark matter and novel materials as for instance topological insulators and Weyl semimetals; they allowed us to find a physical explanation for and a solution to a standing puzzle in the apparent effect of a magnetic field on the critical temperature of the QCD chiral transition; and they led us to establish by the first time that the core of the observed two-solar-mass neutron stars could be made up of quark matter in certain inhomogeneous chiral phases in a magnetic field and that this was consistent with current astrophysical observations. A major goal established by the Nuclear Science Advisory committee in its most recent report “Reaching for the Horizon” has been “to truly understand how nuclei and strongly interacting matter in all its forms behave and can predict their behavior in new settings.” The results found in this DOE project have all contributed to address this goal, and thus they are important for advancing fundamental knowledge in the area of nuclear physics and for enhancing our understanding of the role of strong magnetic fields in the two settings where they are most relevant, neutron stars and heavy-ion collisions.

  8. Final Report for Project. Quark matter under extreme conditions

    International Nuclear Information System (INIS)

    Incera, Vivian; Ferrer, Efrain

    2015-01-01

    The results obtained in the two years of the grant have served to shine new light on several important questions about the phases of quantum chromodynamics (QCD) under extreme conditions that include quark matter at high density, as well quark-gluon plasma at high temperatures, both in the presence of strong magnetic fields. The interest in including an external magnetic field on these studies is motivated by the generation of large magnetic fields in off-central heavy-ion collisions and by their common presence in astrophysical compact objects, the two scenarios where the physics of quark matter becomes relevant. The tasks carried out in this DOE project led us, among other things, to discover the first connection between the physics of very dense quark matter and novel materials as for instance topological insulators and Weyl semimetals; they allowed us to find a physical explanation for and a solution to a standing puzzle in the apparent effect of a magnetic field on the critical temperature of the QCD chiral transition; and they led us to establish by the first time that the core of the observed two-solar-mass neutron stars could be made up of quark matter in certain inhomogeneous chiral phases in a magnetic field and that this was consistent with current astrophysical observations. A major goal established by the Nuclear Science Advisory committee in its most recent report 'Reaching for the Horizon' has been 'to truly understand how nuclei and strongly interacting matter in all its forms behave and can predict their behavior in new settings.' The results found in this DOE project have all contributed to address this goal, and thus they are important for advancing fundamental knowledge in the area of nuclear physics and for enhancing our understanding of the role of strong magnetic fields in the two settings where they are most relevant, neutron stars and heavy-ion collisions.

  9. Extremal surface barriers

    International Nuclear Information System (INIS)

    Engelhardt, Netta; Wall, Aron C.

    2014-01-01

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy

  10. An Invariant-Preserving ALE Method for Solids under Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sambasivan, Shiv Kumar [Los Alamos National Laboratory; Christon, Mark A [Los Alamos National Laboratory

    2012-07-17

    We are proposing a fundamentally new approach to ALE methods for solids undergoing large deformation due to extreme loading conditions. Our approach is based on a physically-motivated and mathematically rigorous construction of the underlying Lagrangian method, vector/tensor reconstruction, remapping, and interface reconstruction. It is transformational because it deviates dramatically from traditionally accepted ALE methods and provides the following set of unique attributes: (1) a three-dimensional, finite volume, cell-centered ALE framework with advanced hypo-/hyper-elasto-plastic constitutive theories for solids; (2) a new physically and mathematically consistent reconstruction method for vector/tensor fields; (3) advanced invariant-preserving remapping algorithm for vector/tensor quantities; (4) moment-of-fluid (MoF) interface reconstruction technique for multi-material problems with solids undergoing large deformations. This work brings together many new concepts, that in combination with emergent cell-centered Lagrangian hydrodynamics methods will produce a cutting-edge ALE capability and define a new state-of-the-art. Many ideas in this work are new, completely unexplored, and hence high risk. The proposed research and the resulting algorithms will be of immediate use in Eulerian, Lagrangian and ALE codes under the ASC program at the lab. In addition, the research on invariant preserving reconstruction/remap of tensor quantities is of direct interest to ongoing CASL and climate modeling efforts at LANL. The application space impacted by this work includes Inertial Confinement Fusion (ICF), Z-pinch, munition-target interactions, geological impact dynamics, shock processing of powders and shaped charges. The ALE framework will also provide a suitable test-bed for rapid development and assessment of hypo-/hyper-elasto-plastic constitutive theories. Today, there are no invariant-preserving ALE algorithms for treating solids with large deformations. Therefore

  11. Extreme High-Temperature Events Over East Asia in 1.5°C and 2°C Warmer Futures: Analysis of NCAR CESM Low-Warming Experiments

    Science.gov (United States)

    Li, Donghuan; Zhou, Tianjun; Zou, Liwei; Zhang, Wenxia; Zhang, Lixia

    2018-02-01

    Extreme high-temperature events have large socioeconomic and human health impacts. East Asia (EA) is a populous region, and it is crucial to assess the changes in extreme high-temperature events in this region under different climate change scenarios. The Community Earth System Model low-warming experiment data were applied to investigate the changes in the mean and extreme high temperatures in EA under 1.5°C and 2°C warming conditions above preindustrial levels. The results show that the magnitude of warming in EA is approximately 0.2°C higher than the global mean. Most populous subregions, including eastern China, the Korean Peninsula, and Japan, will see more intense, more frequent, and longer-lasting extreme temperature events under 1.5°C and 2°C warming. The 0.5°C lower warming will help avoid 35%-46% of the increases in extreme high-temperature events in terms of intensity, frequency, and duration in EA with maximal avoidance values (37%-49%) occurring in Mongolia. Thus, it is beneficial for EA to limit the warming target to 1.5°C rather than 2°C.

  12. Probing the local, electronic and magnetic structure of matter under extreme conditions of temperature and pressure

    DEFF Research Database (Denmark)

    Torchio, R.; Boccato, S.; Cerantola, V.

    2016-01-01

    In this paper we present recent achievements in the field of investigation of the local, electronic and magnetic structure of the matter under extreme conditions of pressure and temperature. These results were obtained thanks to the coupling of a compact laser heating system to the energy-dispersive...

  13. Insertion sequences enrichment in extreme Red sea brine pool vent

    KAUST Repository

    Elbehery, Ali H. A.

    2016-12-03

    Mobile genetic elements are major agents of genome diversification and evolution. Limited studies addressed their characteristics, including abundance, and role in extreme habitats. One of the rare natural habitats exposed to multiple-extreme conditions, including high temperature, salinity and concentration of heavy metals, are the Red Sea brine pools. We assessed the abundance and distribution of different mobile genetic elements in four Red Sea brine pools including the world’s largest known multiple-extreme deep-sea environment, the Red Sea Atlantis II Deep. We report a gradient in the abundance of mobile genetic elements, dramatically increasing in the harshest environment of the pool. Additionally, we identified a strong association between the abundance of insertion sequences and extreme conditions, being highest in the harshest and deepest layer of the Red Sea Atlantis II Deep. Our comparative analyses of mobile genetic elements in secluded, extreme and relatively non-extreme environments, suggest that insertion sequences predominantly contribute to polyextremophiles genome plasticity.

  14. High-resolution stochastic generation of extreme rainfall intensity for urban drainage modelling applications

    Science.gov (United States)

    Peleg, Nadav; Blumensaat, Frank; Molnar, Peter; Fatichi, Simone; Burlando, Paolo

    2016-04-01

    Urban drainage response is highly dependent on the spatial and temporal structure of rainfall. Therefore, measuring and simulating rainfall at a high spatial and temporal resolution is a fundamental step to fully assess urban drainage system reliability and related uncertainties. This is even more relevant when considering extreme rainfall events. However, the current space-time rainfall models have limitations in capturing extreme rainfall intensity statistics for short durations. Here, we use the STREAP (Space-Time Realizations of Areal Precipitation) model, which is a novel stochastic rainfall generator for simulating high-resolution rainfall fields that preserve the spatio-temporal structure of rainfall and its statistical characteristics. The model enables a generation of rain fields at 102 m and minute scales in a fast and computer-efficient way matching the requirements for hydrological analysis of urban drainage systems. The STREAP model was applied successfully in the past to generate high-resolution extreme rainfall intensities over a small domain. A sub-catchment in the city of Luzern (Switzerland) was chosen as a case study to: (i) evaluate the ability of STREAP to disaggregate extreme rainfall intensities for urban drainage applications; (ii) assessing the role of stochastic climate variability of rainfall in flow response and (iii) evaluate the degree of non-linearity between extreme rainfall intensity and system response (i.e. flow) for a small urban catchment. The channel flow at the catchment outlet is simulated by means of a calibrated hydrodynamic sewer model.

  15. Asthma in Patients Climbing to High and Extreme Altitudes in the Tibetan Everest Region

    NARCIS (Netherlands)

    Huismans, Henrike K.; Douma, W. Rob; Kerstjens, Huib A. M.; Renkema, Tineke E. J.

    Objectives: The aim of this study was to investigate the behavior of asthma in patients traveling to high and extreme altitudes. Methods: Twenty-four Dutch patients with mild asthma did a trekking at high and extreme altitudes (up to 6410 m = 21030 ft) in the Tibetan Everest region. Asthma symptoms,

  16. A joint analysis of wave and surge conditions for past and present extrem events in the south-western Baltic Sea

    Science.gov (United States)

    Groll, Nikolaus; Gaslikova, Lidia

    2017-04-01

    Extreme marine events in the south-western Baltic Sea like the historic storm in 1872 are rare, but have large impacts on human safety and coastal infrastructure. The aforementioned extreme storm event of 1872 and has cost over 250 human lives, left severely damaged infrastructure and caused land loss due to coastal erosion. Recent extreme events also result in drastic impacts to coastal regions. Using results from numerical wave and hydrodynamic model simulations we will present a joint analysis of wave and water level conditions for selected extreme events. For the historic event the numerical models have been forced by reconstructed wind and pressure fields from pressure readings. Simulated atmospheric conditions from reanalysis have been used for the more recent events. The height of the water level due to the possible previous inflow of water masses in the Baltic Sea basin, as well as possible seiches and swell effects have been incorporated in the simulations. We will discuss similarities and differences between the historic and the more recent marine hazard events.

  17. High resolution extremity CT for biomechanics modeling

    International Nuclear Information System (INIS)

    Ashby, A.E.; Brand, H.; Hollerbach, K.; Logan, C.M.; Martz, H.E.

    1995-01-01

    With the advent of ever more powerful computing and finite element analysis (FEA) capabilities, the bone and joint geometry detail available from either commercial surface definitions or from medical CT scans is inadequate. For dynamic FEA modeling of joints, precise articular contours are necessary to get appropriate contact definition. In this project, a fresh cadaver extremity was suspended in parafin in a lucite cylinder and then scanned with an industrial CT system to generate a high resolution data set for use in biomechanics modeling

  18. High resolution extremity CT for biomechanics modeling

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, A.E.; Brand, H.; Hollerbach, K.; Logan, C.M.; Martz, H.E.

    1995-09-23

    With the advent of ever more powerful computing and finite element analysis (FEA) capabilities, the bone and joint geometry detail available from either commercial surface definitions or from medical CT scans is inadequate. For dynamic FEA modeling of joints, precise articular contours are necessary to get appropriate contact definition. In this project, a fresh cadaver extremity was suspended in parafin in a lucite cylinder and then scanned with an industrial CT system to generate a high resolution data set for use in biomechanics modeling.

  19. Predicting the solubility of gases in Nitrile Butadiene Rubber in extreme conditions using molecular simulation

    Science.gov (United States)

    Khawaja, Musab; Molinari, Nicola; Sutton, Adrian; Mostofi, Arash

    In the oil and gas industry, elastomer seals play an important role in protecting sensitive monitoring equipment from contamination by gases - a problem that is exacerbated by the high pressures and temperatures found down-hole. The ability to predict and prevent such permeative failure has proved elusive to-date. Nitrile butadiene rubber (NBR) is a common choice of elastomer for seals due to its resistance to heat and fuels. In the conditions found in the well it readily absorbs small molecular weight gases. How this behaviour changes quantitatively for different gases as a function of temperature and pressure is not well-understood. In this work a series of fully atomistic simulations are performed to understand the effect of extreme conditions on gas solubility in NBR. Widom particle insertion is used to compute solubilities. The importance of sampling and allowing structural relaxation upon compression are highlighted, and qualitatively reasonable trends reproduced. Finally, while at STP it has previously been shown that the solubility of CO2 is higher than that of He in NBR, we observe that under the right circumstances it is possible to reverse this trend.

  20. On the Performance of Carbon Nanotubes in Extreme Conditions and in the Presence of Microwaves

    Science.gov (United States)

    2013-01-01

    been considered for use as transparent conductors include: transparent conducting oxides (TCOs), intrinsically conducting polymers (ICPs), graphene ...optical transmission properties, but are extremely sensitive to environmental conditions (such as temperature and humidity). Graphene has recently...during the dicing procedure, silver paint was applied to the sample to serve as improvised contact/probe-landing points. Figure 1 shows the CNT thin

  1. The Extreme Male Brain Theory and Gender Role Behaviour in Persons with an Autism Spectrum Condition

    Science.gov (United States)

    Stauder, J. E. A.; Cornet, L. J. M.; Ponds, R. W. H. M.

    2011-01-01

    According to the Extreme Male Brain theory persons with autism possess masculinised cognitive traits. In this study masculinisation of gender role behaviour is evaluated in 25 persons with an autism spectrum condition (ASC) and matched controls with gender role behaviour as part of a shortened version of the Minnesota Multiphasic Personality…

  2. Production processes at extremely high energies

    CERN Document Server

    Gastmans, R; Wu, Tai Tsun

    2013-01-01

    The production processes are identified that contribute to the rise of the total cross section in proton-proton scattering at extremely high energies, s->~. At such energies, the scattering can be described by a black disk (completely absorptive) with a radius expanding logarithmically with energy surrounded by a gray fringe (partially absorptive). For the leading term of (lns)^2 in the increasing total cross section, the gray fringe is neglected, and geometrical optics is generalized to production processes. It is known that half of the rise in the total cross section is due to elastic scattering. The other half is found to originate from the production of jets with relatively small momenta in the center-of-mass system.

  3. Evolution of self-organization in nano-structured PVD coatings under extreme tribological conditions

    Energy Technology Data Exchange (ETDEWEB)

    Fox-Rabinovich, G., E-mail: gfox@mcmaster.ca [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada); Kovalev, A. [Surface Phenomena Researches Group, CNIICHERMET, 9/23, 2-nd Baumanskaya Street, Moscow 105005 (Russian Federation); Aguirre, M.H. [Laboratory of Advanced Microscopy, Institute of Nanoscience of Aragón, University of Zaragoza, 50018 Zaragoza (Spain); Yamamoto, K. [Materials Research Laboratory, Kobe Steel Ltd, 1-5-5 Takatsuda-dai, Nishi-ku, Kobe 651-2271, Hyogo (Japan); Veldhuis, S. [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada); Gershman, I. [All-Russian Railway Research Institute, 10 Third Mytishchinskaya Street, Moscow 29851 (Russian Federation); Rashkovskiy, A. [Surface Phenomena Researches Group, CNIICHERMET, 9/23, 2-nd Baumanskaya Street, Moscow 105005 (Russian Federation); Endrino, J.L. [Albengoa Research, Energia Solar 1, Palmas Altas, Seville 41014 (Spain); Beake, B. [Micro Materials Limited, Willow House, Yale Business Village, Ellice Way, Wrexham LL13 7YL (United Kingdom); Dosbaeva, G. [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada); Wainstein, D. [Surface Phenomena Researches Group, CNIICHERMET, 9/23, 2-nd Baumanskaya Street, Moscow 105005 (Russian Federation); Yuan, Junifeng; Bunting, J.W. [Department of Mechanical Engineering, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L7 (Canada)

    2014-04-01

    Highlights: • The evolution of self-organization under extreme frictional conditions has been studied. • Comprehensive characterization of the tribo-films was made using various surface analytical techniques. • During the running-in stage, mullite tribo-ceramics predominate on the surface of the nano-multilayer coating, establishing a functional hierarchy within the layer of tribo-films. • It is possible to control tribo-film evolution during self-organization by means of an increase in structural complexity and the non-equilibrium state of the surface engineered layer. - Abstract: The evolution of the self-organization process where dissipative structures are formed under the extreme frictional conditions associated with high performance dry machining of hardened steels has been studied in detail. The emphasis was on the progressive studies of surface transformations within multilayer and monolayer TiAlCrSiYN-based PVD coatings during the running-in stage of wear when self-organization process occurs. The coating layer was characterized by high resolution electron energy-loss spectroscopy (HREELS). It is shown that the nano-multilayer coating possesses higher non-equilibrium structure in comparison to the monolayer. Comprehensive studies of the tribo-films (dissipative structures) formed on the friction surface were made using a number of advanced surface characterization techniques such as X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). The data obtained for the tribo-films was combined with the detailed TEM studies of the structural and phase transformations within the underlying coating layer. This data was related to the micro-mechanical characteristics of the coating layer and its wear resistance. It was demonstrated that the evolution of the self-organization process is strongly controlled by the characteristics of the tribo-films formed at different stages of the wear process. Within running-in stage (after

  4. Performance of PICS bags under extreme conditions in the sahel zone of Niger.

    Science.gov (United States)

    Baoua, Ibrahim B; Bakoye, Ousmane; Amadou, Laouali; Murdock, Larry L; Baributsa, Dieudonne

    2018-03-01

    Experiments in Niger assessed whether extreme environmental conditions including sunlight exposure affect the performance of triple-layer PICS bags in protecting cowpea grain against bruchids. Sets of PICS bags and woven polypropylene bags as controls containing 50 kg of naturally infested cowpea grain were held in the laboratory or outside with sun exposure for four and one-half months. PICS bags held either inside or outside exhibited no significant increase in insect damage and no loss in weight after 4.5 months of storage compared to the initial values. By contrast, woven bags stored inside or outside side by side with PICS bags showed several-fold increases in insects present in or on the grain and significant losses in grain weight. Grain stored inside in PICS bags showed no reduction in germination versus the initial value but there was a small but significant drop in germination of grain in PICS bags held outside (7.6%). Germination rates dropped substantially more in grain stored in woven bags inside (16.1%) and still more in woven bags stored outside (60%). PICS bags held inside and outside retained their ability to maintain internal reduced levels of oxygen and elevated levels of carbon dioxide. Exposure to extreme environmental conditions degraded the external polypropylene outer layer of the PICS triple-layer bag. Even so, the internal layers of polyethylene were more slowly degraded. The effects of exposure to sunlight, temperature and humidity variation within the sealed bags are described.

  5. Extreme eigenvalues of sample covariance and correlation matrices

    DEFF Research Database (Denmark)

    Heiny, Johannes

    This thesis is concerned with asymptotic properties of the eigenvalues of high-dimensional sample covariance and correlation matrices under an infinite fourth moment of the entries. In the first part, we study the joint distributional convergence of the largest eigenvalues of the sample covariance...... matrix of a p-dimensional heavy-tailed time series when p converges to infinity together with the sample size n. We generalize the growth rates of p existing in the literature. Assuming a regular variation condition with tail index ... eigenvalues are essentially determined by the extreme order statistics from an array of iid random variables. The asymptotic behavior of the extreme eigenvalues is then derived routinely from classical extreme value theory. The resulting approximations are strikingly simple considering the high dimension...

  6. Higher order magnetic modulation structures in rare earth metal, alloys and compounds under extreme conditions

    International Nuclear Information System (INIS)

    Kawano, S.

    2003-01-01

    Magnetic materials consisting of rare earth ions form modulation structures such as a helical or sinusoidal structure caused by the oscillating magnetic interaction between rare earth ions due to RKKY magnetic interaction. These modulation structures, in some cases, develop further to higher order modulation structures by additional modulations caused by higher order crystalline electric field, magnetic interactions such as spin-lattice interaction, external magnetic field and pressure. The higher order modulation structures are observed in a spin-slip structure or a helifan structure in Ho, and a tilt helix structure in a TbEr alloy. Paramagnetic ions originated from frustration generate many magnetic phases under applied external magnetic field. KUR neutron diffraction groups have performed the development and adjustment of high-pressure instruments and external magnetic fields for neutron diffraction spectrometers. The studies of 'neutron diffraction under extreme conditions' by the seven groups are described in this report. (Y. Kazumata)

  7. A single pH fluorescent probe for biosensing and imaging of extreme acidity and extreme alkalinity.

    Science.gov (United States)

    Chao, Jian-Bin; Wang, Hui-Juan; Zhang, Yong-Bin; Li, Zhi-Qing; Liu, Yu-Hong; Huo, Fang-Jun; Yin, Cai-Xia; Shi, Ya-Wei; Wang, Juan-Juan

    2017-07-04

    A simple tailor-made pH fluorescent probe 2-benzothiazole (N-ethylcarbazole-3-yl) hydrazone (Probe) is facilely synthesized by the condensation reaction of 2-hydrazinobenzothiazole with N-ethylcarbazole-3-formaldehyde, which is a useful fluorescent probe for monitoring extremely acidic and alkaline pH, quantitatively. The pH titrations indicate that Probe displays a remarkable emission enhancement with a pK a of 2.73 and responds linearly to minor pH fluctuations within the extremely acidic range of 2.21-3.30. Interestingly, Probe also exhibits strong pH-dependent characteristics with pK a 11.28 and linear response to extreme-alkalinity range of 10.41-12.43. In addition, Probe shows a large Stokes shift of 84 nm under extremely acidic and alkaline conditions, high selectivity, excellent sensitivity, good water-solubility and fine stability, all of which are favorable for intracellular pH imaging. The probe is further successfully applied to image extremely acidic and alkaline pH values fluctuations in E. coli cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. The need of the change of the conceptualisation of hydrologic processes under extreme conditions – taking reference evapotranspiration as an example

    Directory of Open Access Journals (Sweden)

    S. Liu

    2015-06-01

    Full Text Available What a hydrological model displays is the relationships between the output and input in daily, monthly, yearly and other temporal scales. In the case of climate change or other environment changes, the input of the hydrological model may show a gradual or abrupt change. There have been numerous documented studies to explore the response of output of the hydrological models to the change of the input with scenario simulation. Most of the studies assumed that the conceptualisation of hydrologic processes will remain, which may be true for the gradual change of the input. However, under extreme conditions the conceptualisation of hydrologic processes may be completely changed. Taking an example of the Allen's formula to calculate crop reference evapotranspiration (ET0 as a simple hydrological model, we analyze the alternation of the extreme in ET0 from 1955 to 2012 at the Chongling Experimental Station located in Hebei Province, China. The relationships between ET0 and the meteorological factors for the average values, minimum (maximum values at daily, monthly and annual scales are revealed. It is found the extreme of the output can follow the extreme of the input better when their relationship is more linear. For non-liner relationship, the extreme of the input cannot at all be reflected from the extreme of the output. Relatively, extreme event at daily scale is harder to be shown than that at monthly scale. The result implicates that a routine model may not be able to catch the response to extreme events and it is even more so as we extrapolate models to higher temperature/CO2 conditions in the future. Some possible choices for the improvements are suggested for predicting hydrological extremes.

  9. Toward Improving Predictability of Extreme Hydrometeorological Events: the Use of Multi-scale Climate Modeling in the Northern High Plains

    Science.gov (United States)

    Munoz-Arriola, F.; Torres-Alavez, J.; Mohamad Abadi, A.; Walko, R. L.

    2014-12-01

    Our goal is to investigate possible sources of predictability of hydrometeorological extreme events in the Northern High Plains. Hydrometeorological extreme events are considered the most costly natural phenomena. Water deficits and surpluses highlight how the water-climate interdependence becomes crucial in areas where single activities drive economies such as Agriculture in the NHP. Nonetheless we recognize the Water-Climate interdependence and the regulatory role that human activities play, we still grapple to identify what sources of predictability could be added to flood and drought forecasts. To identify the benefit of multi-scale climate modeling and the role of initial conditions on flood and drought predictability on the NHP, we use the Ocean Land Atmospheric Model (OLAM). OLAM is characterized by a dynamic core with a global geodesic grid with hexagonal (and variably refined) mesh cells and a finite volume discretization of the full compressible Navier Stokes equations, a cut-grid cell method for topography (that reduces error in computational gradient computation and anomalous vertical dispersion). Our hypothesis is that wet conditions will drive OLAM's simulations of precipitation to wetter conditions affecting both flood forecast and drought forecast. To test this hypothesis we simulate precipitation during identified historical flood events followed by drought events in the NHP (i.e. 2011-2012 years). We initialized OLAM with CFS-data 1-10 days previous to a flooding event (as initial conditions) to explore (1) short-term and high-resolution and (2) long-term and coarse-resolution simulations of flood and drought events, respectively. While floods are assessed during a maximum of 15-days refined-mesh simulations, drought is evaluated during the following 15 months. Simulated precipitation will be compared with the Sub-continental Observation Dataset, a gridded 1/16th degree resolution data obtained from climatological stations in Canada, US, and

  10. Opacity calculations for extreme physical systems: code RACHEL

    Science.gov (United States)

    Drska, Ladislav; Sinor, Milan

    1996-08-01

    Computer simulations of physical systems under extreme conditions (high density, temperature, etc.) require the availability of extensive sets of atomic data. This paper presents basic information on a self-consistent approach to calculations of radiative opacity, one of the key characteristics of such systems. After a short explanation of general concepts of the atomic physics of extreme systems, the structure of the opacity code RACHEL is discussed and some of its applications are presented.

  11. Impact of urban WWTP and CSO fluxes on river peak flow extremes under current and future climate conditions.

    Science.gov (United States)

    Keupers, Ingrid; Willems, Patrick

    2013-01-01

    The impact of urban water fluxes on the river system outflow of the Grote Nete catchment (Belgium) was studied. First the impact of the Waste Water Treatment Plant (WWTP) and the Combined Sewer Overflow (CSO) outflows on the river system for the current climatic conditions was determined by simulating the urban fluxes as point sources in a detailed, hydrodynamic river model. Comparison was made of the simulation results on peak flow extremes with and without the urban point sources. In a second step, the impact of climate change scenarios on the urban fluxes and the consequent impacts on the river flow extremes were studied. It is shown that the change in the 10-year return period hourly peak flow discharge due to climate change (-14% to +45%) was in the same order of magnitude as the change due to the urban fluxes (+5%) in current climate conditions. Different climate change scenarios do not change the impact of the urban fluxes much except for the climate scenario that involves a strong increase in rainfall extremes in summer. This scenario leads to a strong increase of the impact of the urban fluxes on the river system.

  12. Spatial extreme value analysis to project extremes of large-scale indicators for severe weather.

    Science.gov (United States)

    Gilleland, Eric; Brown, Barbara G; Ammann, Caspar M

    2013-09-01

    Concurrently high values of the maximum potential wind speed of updrafts ( W max ) and 0-6 km wind shear (Shear) have been found to represent conducive environments for severe weather, which subsequently provides a way to study severe weather in future climates. Here, we employ a model for the product of these variables (WmSh) from the National Center for Atmospheric Research/United States National Center for Environmental Prediction reanalysis over North America conditioned on their having extreme energy in the spatial field in order to project the predominant spatial patterns of WmSh. The approach is based on the Heffernan and Tawn conditional extreme value model. Results suggest that this technique estimates the spatial behavior of WmSh well, which allows for exploring possible changes in the patterns over time. While the model enables a method for inferring the uncertainty in the patterns, such analysis is difficult with the currently available inference approach. A variation of the method is also explored to investigate how this type of model might be used to qualitatively understand how the spatial patterns of WmSh correspond to extreme river flow events. A case study for river flows from three rivers in northwestern Tennessee is studied, and it is found that advection of WmSh from the Gulf of Mexico prevails while elsewhere, WmSh is generally very low during such extreme events. © 2013 The Authors. Environmetrics published by JohnWiley & Sons, Ltd.

  13. Design, fabrication, and characterization of high-efficiency extreme ultraviolet diffusers

    Energy Technology Data Exchange (ETDEWEB)

    Naulleau, Patrick P.; Liddle, J. Alexander; Salmassi, Farhad; Anderson, Erik H.; Gullikson, Eric M.

    2004-02-19

    As the development of extreme ultraviolet (EUV) lithography progresses, interest grows in the extension of traditional optical components to the EUV regime. The strong absorption of EUV by most materials and its extremely short wavelength, however, makes it very difficult to implement many components that are commonplace in the longer wavelength regimes. One such example is the diffuser often implemented with ordinary ground glass in the visible light regime. Here we demonstrate the fabrication of reflective EUV diffusers with high efficiency within a controllable bandwidth. Using these techniques we have fabricated diffusers with efficiencies exceeding 10% within a moderate angular single-sided bandwidth of approximately 0.06 radians.

  14. [The action of low-intensity extremely high-freguency electromagnetic radiation on growth parameters for bacteria Enterococcus hirae].

    Science.gov (United States)

    Oganian, V; Sarkisian, A; Tadevosian, A; Torchunian, A

    2008-01-01

    It has been found that the exposure of Enterococcus hirae ATCC9790, grown under anaerobic conditions for 30 min or 1 h, to low-intensity (flux capacity 0.06 mW/sm2) coherent electromagnetic radiation (EMI) of extremely high-frequency 45 - 53 GHz), or millimeter waves causes a marked prolongation of the lag-growth phase and a decrease in their specific growth rate, the inhibitory effect increasing in the frequency range from 49 to 53 GHz. The effect enhanced as duration of expocure was encreased from 30 min to 1 h; however, further increase in exposure duration to 2 h did not cause an enhancement of the effect. It has been shown that the action of extremely high-frequency EMI on these bacteria does not depend on medium pH (pH 8.0 or pH 6.0). It is proposed that these bacteria have defensive or reparation mechanisms which compensate for the action of radiation; the occurrence of different mechanisms for pH regulation is not ruled out.

  15. Bright high-repetition-rate source of narrowband extreme-ultraviolet harmonics beyond 22 eV

    Energy Technology Data Exchange (ETDEWEB)

    Wang, He [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Xu, Yiming [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Ulonska, Stefan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Robinson, Joseph S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Ranitovic, Predrag [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Kaindl, Robert A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division

    2015-06-11

    Novel table-top sources of extreme-ultraviolet light based on high-harmonic generation yield unique insight into the fundamental properties of molecules, nanomaterials or correlated solids, and enable advanced applications in imaging or metrology. Extending high-harmonic generation to high repetition rates portends great experimental benefits, yet efficient extreme-ultraviolet conversion of correspondingly weak driving pulses is challenging. In this article, we demonstrate a highly-efficient source of femtosecond extreme-ultraviolet pulses at 50-kHz repetition rate, utilizing the ultraviolet second-harmonic focused tightly into Kr gas. In this cascaded scheme, a photon flux beyond ≈3 × 1013 s-1 is generated at 22.3 eV, with 5 × 10-5 conversion efficiency that surpasses similar harmonics directly driven by the fundamental by two orders-of-magnitude. The enhancement arises from both wavelength scaling of the atomic dipole and improved spatio-temporal phase matching, confirmed by simulations. Finally, spectral isolation of a single 72-meV-wide harmonic renders this bright, 50-kHz extreme-ultraviolet source a powerful tool for ultrafast photoemission, nanoscale imaging and other applications.

  16. Forecasting of flowrate under rolling motion flow instability condition based on on-line sequential extreme learning machine

    International Nuclear Information System (INIS)

    Chen Hanying; Gao Puzhen; Tan Sichao; Tang Jiguo; Hou Xiaofan; Xu Huiqiang; Wu Xiangcheng

    2015-01-01

    The coupling of multiple thermal-hydraulic parameters can result in complex flow instability in natural circulation system under rolling motion. A real-time thermal-hydraulic condition prediction is helpful to the operation of systems in such condition. A single hidden layer feedforward neural networks algorithm named extreme learning machine (ELM) is considered as suitable method for this application because of its extremely fast training time, good accuracy and simplicity. However, traditional ELM assumes that all the training data are ready before the training process, while the training data is received sequentially in practical forecasting of flowrate. Therefore, this paper proposes a forecasting method for flowrate under rolling motion based on on-line sequential ELM (OS-ELM), which can learn the data one by one or chunk-by-chunk. The experiment results show that the OS-ELM method can achieve a better forecasting performance than basic ELM method and still keep the advantage of fast training and simplicity. (author)

  17. Atmospheric conditions associated with extreme fire activity in the Western Mediterranean region.

    Science.gov (United States)

    Amraoui, Malik; Pereira, Mário G; DaCamara, Carlos C; Calado, Teresa J

    2015-08-15

    Active fire information provided by TERRA and AQUA instruments on-board sun-synchronous polar MODIS platform is used to describe fire activity in the Western Mediterranean and to identify and characterize the synoptic patterns of several meteorological fields associated with the occurrence of extreme fire activity episodes (EEs). The spatial distribution of the fire pixels during the period of 2003-2012 leads to the identification of two most affected sub-regions, namely the Northern and Western parts of the Iberian Peninsula (NWIP) and Northern Africa (NAFR). The temporal distribution of the fire pixels in these two sub-regions is characterized by: (i) high and non-concurrent inter- and intra-annual variability with maximum values during the summer of 2003 and 2005 in NWIP and 2007 and 2012 in NAFR; and, (ii) high intra-annual variability dominated by a prominent annual cycle with a main peak centred in August in both sub-regions and a less pronounced secondary peak in March only evident in NWIP region. The 34 EEs identified were grouped according to the location, period of occurrence and spatial configuration of the associated synoptic patterns into 3 clusters (NWIP-summer, NWIP-winter and NAFR-summer). Results from the composite analysis reveal similar fire weather conditions (statistically significant positive anomalies of air temperature and negative anomalies of air relative humidity) but associated with different circulation patterns at lower and mid-levels of the atmosphere associated with the occurrence of EEs in each cluster of the Western Mediterranean region. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Specialized or opportunistic-how does the high mountain endemic butterfly Erebia nivalis survive in its extreme habitats?

    Science.gov (United States)

    Ehl, Stefan; Dalstein, Vivian; Tull, Fabienne; Gros, Patrick; Schmitt, Thomas

    2018-02-01

    High mountain ecosystems are a challenge for the survival of animal and plant species, which have to evolve specific adaptations to cope with the prevailing extreme conditions. The strategies to survive may reach from opportunistic to highly adapted traits. One species successfully surviving under these conditions is the here studied butterfly Erebia nivalis. In a mark-release-recapture study performed in the Hohe Tauern National Park (Austria) from 22 July to 26 August 2013, we marked 1386 individuals and recaptured 342 of these. For each capture event, we recorded the exact point of capture and various other traits (wing conditions, behavior, nectar sources). The population showed a partial protandrous demography with the minority of males emerging prior to the females, but the majority being synchronized with them. Males and females differed significantly in their behavior with males being more flight active and females nectaring and resting more. Both sexes showed preferences for the same plant species as nectar sources, but this specialization apparently is the result of a rapid individual adaptation to the locally available flowers. Estimates of the realized dispersal distances predicted a comparatively high amount of long-distance flights, especially for females. Therefore, the adaptation of Erebia nivalis to the unpredictable high mountain conditions might be a mixture of opportunism and specialized traits. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  19. Atmospheric conditions during high ragweed pollen concentrations in Zagreb, Croatia

    Science.gov (United States)

    Prtenjak, Maja Telišman; Srnec, Lidija; Peternel, Renata; Madžarević, Valentina; Hrga, Ivana; Stjepanović, Barbara

    2012-11-01

    We examined the atmospheric conditions favourable to the occurrence of maximum concentrations of ragweed pollen with an extremely high risk of producing allergy. Over the 2002-2009 period, daily pollen data collected in Zagreb were used to identify two periods of high pollen concentration (> 600 grains/m3) for our analysis: period A (3-4 September 2002) and period B (6-7 September 2003). Synoptic conditions in both periods were very similar: Croatia was under the influence of a lower sector high pressure system moving slowly eastward over Eastern Europe. During the 2002-2009 period, this type of weather pattern (on ~ 70% of days), in conjunction with almost non-gradient surface pressure conditions in the area (on ~ 30% of days) characterised days when the daily pollen concentrations were higher than 400 grains/m3. Numerical experiments using a mesoscale model at fine resolution showed successful multi-day simulations reproducing the local topographic influence on wind flow and in reasonable agreement with available observations. According to the model, the relatively weak synoptic flow (predominantly from the eastern direction) allowed local thermal circulations to develop over Zagreb during both high pollen episodes. Two-hour pollen concentrations and 48-h back-trajectories indicated that regional-range transport of pollen grains from the central Pannonian Plain was the cause of the high pollen concentrations during period A. During period B, the north-westward regional-range transport in Zagreb was supplemented significantly by pronounced horizontal recirculation of pollen grains. This recirculation happened within the diurnal local circulation over the city, causing a late-evening increase in pollen concentration.

  20. Future changes in hydro-climatic extremes in the Upper Indus, Ganges, and Brahmaputra River basins.

    Science.gov (United States)

    Wijngaard, René R; Lutz, Arthur F; Nepal, Santosh; Khanal, Sonu; Pradhananga, Saurav; Shrestha, Arun B; Immerzeel, Walter W

    2017-01-01

    Future hydrological extremes, such as floods and droughts, may pose serious threats for the livelihoods in the upstream domains of the Indus, Ganges, Brahmaputra. For this reason, the impacts of climate change on future hydrological extremes is investigated in these river basins. We use a fully-distributed cryospheric-hydrological model to simulate current and future hydrological fluxes and force the model with an ensemble of 8 downscaled General Circulation Models (GCMs) that are selected from the RCP4.5 and RCP8.5 scenarios. The model is calibrated on observed daily discharge and geodetic mass balances. The climate forcing and the outputs of the hydrological model are used to evaluate future changes in climatic extremes, and hydrological extremes by focusing on high and low flows. The outcomes show an increase in the magnitude of climatic means and extremes towards the end of the 21st century where climatic extremes tend to increase stronger than climatic means. Future mean discharge and high flow conditions will very likely increase. These increases might mainly be the result of increasing precipitation extremes. To some extent temperature extremes might also contribute to increasing discharge extremes, although this is highly dependent on magnitude of change in temperature extremes. Low flow conditions may occur less frequently, although the uncertainties in low flow projections can be high. The results of this study may contribute to improved understanding on the implications of climate change for the occurrence of future hydrological extremes in the Hindu Kush-Himalayan region.

  1. Future changes in hydro-climatic extremes in the Upper Indus, Ganges, and Brahmaputra River basins.

    Directory of Open Access Journals (Sweden)

    René R Wijngaard

    Full Text Available Future hydrological extremes, such as floods and droughts, may pose serious threats for the livelihoods in the upstream domains of the Indus, Ganges, Brahmaputra. For this reason, the impacts of climate change on future hydrological extremes is investigated in these river basins. We use a fully-distributed cryospheric-hydrological model to simulate current and future hydrological fluxes and force the model with an ensemble of 8 downscaled General Circulation Models (GCMs that are selected from the RCP4.5 and RCP8.5 scenarios. The model is calibrated on observed daily discharge and geodetic mass balances. The climate forcing and the outputs of the hydrological model are used to evaluate future changes in climatic extremes, and hydrological extremes by focusing on high and low flows. The outcomes show an increase in the magnitude of climatic means and extremes towards the end of the 21st century where climatic extremes tend to increase stronger than climatic means. Future mean discharge and high flow conditions will very likely increase. These increases might mainly be the result of increasing precipitation extremes. To some extent temperature extremes might also contribute to increasing discharge extremes, although this is highly dependent on magnitude of change in temperature extremes. Low flow conditions may occur less frequently, although the uncertainties in low flow projections can be high. The results of this study may contribute to improved understanding on the implications of climate change for the occurrence of future hydrological extremes in the Hindu Kush-Himalayan region.

  2. Extreme implanting in Si: A study of ion-induced damage at high temperature and high dose

    International Nuclear Information System (INIS)

    Holland, O.W.

    1994-01-01

    Ion-solid interactions near room temperature and below have been well studied in single-crystal Si. While this has led to a better understanding of the mechanisms responsible for nucleation and growth of lattice damage during irradiation, these studies have not, in general, been extended to high temperatures (e.g., >200 degrees C). This is the case despite the commercialization of ion beam technologies which utilize high-temperature processing, such as separation by implantation of oxygen (SIMOX). In this process, a silicon-on-insulator (SOI) material is produced by implanting a high dose of oxygen ions into a Si wafer to form a buried, stoichiometric oxide layer. Results will be presented of a study of damage accumulation during high-dose implantation of Si at elevated temperatures. In particular, O + -ions were used because of the potential impact of the results on the SIMOX technology. It will be shown that the nature of the damage accumulation at elevated temperatures is quite distinctive and portends the presence of a new mechanism, one which is only dominant under the extreme conditions encountered during ion beam synthesis (i.e., high temperature and high dose). This mechanism is discussed and shown to be quite general and not dependent on the chemical identity of the ions. Also, techniques for suppressing this mechanism by open-quotes defect engineeringclose quotes are discussed. Such techniques are technologically relevant because they offer the possibility of reducing the defect density of the SOI produced by SIMOX

  3. The myoglobin of Emperor penguin (Aptenodytes forsteri): amino acid sequence and functional adaptation to extreme conditions.

    Science.gov (United States)

    Tamburrini, M; Romano, M; Giardina, B; di Prisco, G

    1999-02-01

    In the framework of a study on molecular adaptations of the oxygen-transport and storage systems to extreme conditions in Antarctic marine organisms, we have investigated the structure/function relationship in Emperor penguin (Aptenodytes forsteri) myoglobin, in search of correlation with the bird life style. In contrast with previous reports, the revised amino acid sequence contains one additional residue and 15 differences. The oxygen-binding parameters seem well adapted to the diving behaviour of the penguin and to the environmental conditions of the Antarctic habitat. Addition of lactate has no major effect on myoglobin oxygenation over a large temperature range. Therefore, metabolic acidosis does not impair myoglobin function under conditions of prolonged physical effort, such as diving.

  4. Characteristics of extreme ultraviolet emission from high-Z plasmas

    International Nuclear Information System (INIS)

    Ohashi, H.; Higashiguchi, T.; Suzuki, Y.; Kawasaki, M.; Suzuki, C.; Tomita, K.; Nishikino, M.; Fujioka, S.; Endo, A.; Li, B.; Otsuka, T.; Dunne, P.; O'Sullivan, G.

    2016-01-01

    We demonstrate the extreme ultraviolet (EUV) and soft x-ray sources in the 2 to 7 nm spectral region related to the beyond EUV (BEUV) question at 6.x nm and the water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs), extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on high-Z plasma UTA source, coupled to multilayer mirror optics. (paper)

  5. Characteristics of extreme ultraviolet emission from high-Z plasmas

    Science.gov (United States)

    Ohashi, H.; Higashiguchi, T.; Suzuki, Y.; Kawasaki, M.; Suzuki, C.; Tomita, K.; Nishikino, M.; Fujioka, S.; Endo, A.; Li, B.; Otsuka, T.; Dunne, P.; O'Sullivan, G.

    2016-03-01

    We demonstrate the extreme ultraviolet (EUV) and soft x-ray sources in the 2 to 7 nm spectral region related to the beyond EUV (BEUV) question at 6.x nm and the water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs), extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on high-Z plasma UTA source, coupled to multilayer mirror optics.

  6. Probability modeling of high flow extremes in Yingluoxia watershed, the upper reaches of Heihe River basin

    Science.gov (United States)

    Li, Zhanling; Li, Zhanjie; Li, Chengcheng

    2014-05-01

    Probability modeling of hydrological extremes is one of the major research areas in hydrological science. Most basins in humid and semi-humid south and east of China are concerned for probability modeling analysis of high flow extremes. While, for the inland river basin which occupies about 35% of the country area, there is a limited presence of such studies partly due to the limited data availability and a relatively low mean annual flow. The objective of this study is to carry out probability modeling of high flow extremes in the upper reach of Heihe River basin, the second largest inland river basin in China, by using the peak over threshold (POT) method and Generalized Pareto Distribution (GPD), in which the selection of threshold and inherent assumptions for POT series are elaborated in details. For comparison, other widely used probability distributions including generalized extreme value (GEV), Lognormal, Log-logistic and Gamma are employed as well. Maximum likelihood estimate is used for parameter estimations. Daily flow data at Yingluoxia station from 1978 to 2008 are used. Results show that, synthesizing the approaches of mean excess plot, stability features of model parameters, return level plot and the inherent independence assumption of POT series, an optimum threshold of 340m3/s is finally determined for high flow extremes in Yingluoxia watershed. The resulting POT series is proved to be stationary and independent based on Mann-Kendall test, Pettitt test and autocorrelation test. In terms of Kolmogorov-Smirnov test, Anderson-Darling test and several graphical diagnostics such as quantile and cumulative density function plots, GPD provides the best fit to high flow extremes in the study area. The estimated high flows for long return periods demonstrate that, as the return period increasing, the return level estimates are probably more uncertain. The frequency of high flow extremes exhibits a very slight but not significant decreasing trend from 1978 to

  7. Effects of Extreme Temperatures on Cause-Specific Cardiovascular Mortality in China.

    Science.gov (United States)

    Wang, Xuying; Li, Guoxing; Liu, Liqun; Westerdahl, Dane; Jin, Xiaobin; Pan, Xiaochuan

    2015-12-21

    Limited evidence is available for the effects of extreme temperatures on cause-specific cardiovascular mortality in China. We collected data from Beijing and Shanghai, China, during 2007-2009, including the daily mortality of cardiovascular disease, cerebrovascular disease, ischemic heart disease and hypertensive disease, as well as air pollution concentrations and weather conditions. We used Poisson regression with a distributed lag non-linear model to examine the effects of extremely high and low ambient temperatures on cause-specific cardiovascular mortality. For all cause-specific cardiovascular mortality, Beijing had stronger cold and hot effects than those in Shanghai. The cold effects on cause-specific cardiovascular mortality reached the strongest at lag 0-27, while the hot effects reached the strongest at lag 0-14. The effects of extremely low and high temperatures differed by mortality types in the two cities. Hypertensive disease in Beijing was particularly susceptible to both extremely high and low temperatures; while for Shanghai, people with ischemic heart disease showed the greatest relative risk (RRs = 1.16, 95% CI: 1.03, 1.34) to extremely low temperature. People with hypertensive disease were particularly susceptible to extremely low and high temperatures in Beijing. People with ischemic heart disease in Shanghai showed greater susceptibility to extremely cold days.

  8. Study of the CMS RPC detector performance in high radiation background conditions

    CERN Document Server

    Miguel Colin, Osvaldo

    2017-01-01

    The RPC system at the CMS Detector is operating successfully from beginning of the data taking. The high instantaneous luminosity causes an extremely high flux of ionizing particles. The long period of operation (Run1 and Run2) in a huge radiation background conditions, gives the opportunity to study the operation capability of the RPCs and also to predict a data-driven extrapolation about the expecting particle rates at HL LHC (High Luminosity) scenario. The obtained results in terms of measured rate, currents and integrated charged will be presented in the poster. When it is possible they will be compared to the relevant results obtained from the dedicated study where a set of test chambers have been irradiated at GIF++ laboratory setup.

  9. Human Performance under Extreme Conditions with Respect to a Resilient Organisation. Proceedings of a CSNI International Workshop, 24-26 February 2015, Brugg, Switzerland

    International Nuclear Information System (INIS)

    2015-01-01

    After the Fukushima Daiichi accident a number of initiatives have been undertaken internationally to learn from the accident and to implement lessons learned to improve nuclear safety. The accident has shown in particular the challenges in supporting reliable human performance under extreme conditions. Acknowledging that further work is needed to be better prepared for the HOF (Human and Organisational Factors) challenges of the extreme conditions that may be present in severe accidents, the NEA's Working Group on Human and Organisational Factors (WGHOF), one of the working groups for the Committee on the Safety of Nuclear Installations (CSNI) initiated a new task with the objectives to: - share experiences and knowledge of human and organisational performance under extreme conditions, - identify specific currently applied HOF principles in nuclear and other high risk industries and compare them with the available knowledge, - provide a basis for improvements and necessary research taking into account HOF issues in the design and use of measures, and - make recommendations with the aim to achieve the best level of human and organisational performance as possible under extreme conditions. In order to move those issues forward WGHOF hosted together with the Swiss Federal Nuclear Safety Inspectorate ENSI a workshop entitled 'Human Performance under Extreme Conditions with respect to a Resilient Organization'. The workshop was conducted with participation of a number of invited key speakers from academic research and a range of industries, including nuclear. Thirty-four experts from 12 countries, the IAEA and OECD/Halden participated. Experts came from nuclear authorities, research centres, technical support organisations, training simulator centres, utilities and from non-nuclear field (aircraft accident investigation, fire fighting, military, design of resilient organisations). From the discussions at the workshop, it is clear that the accident at Fukushima has

  10. Extreme river flow dependence in Northern Scotland

    Science.gov (United States)

    Villoria, M. Franco; Scott, M.; Hoey, T.; Fischbacher-Smith, D.

    2012-04-01

    predominantly impermeable bedrock, with the Ewe's one being very wet. The Lossie(216km2) and Dulnain (272.2km2) both contain significant areas of glacial deposits. River flow in the Dulnain is usually affected by snowmelt. In all cases, the conditional probability of each of the three rivers (Dulnain, Lossie, Ewe) decreases as the event in the conditioning river (Ness) becomes more extreme. The Ewe, despite being the furthest of the three sites from the Ness shows the strongest dependence, with relatively high (>0.4) conditional probabilities even for very extreme events (>0.995). Although the Lossie is closer geographically to the Ness than the Ewe, it shows relatively low conditional probabilities and can be considered independent of the Ness for very extreme events (> 0.990). The conditional probabilities seem to reflect the different catchment characteristics and dominant precipitation generating events, with the Ewe being more similar to the Ness than the other two rivers. This interpretation suggests that the conditional method may yield improved estimates of extreme events, but the approach is time consuming. An alternative model that is easier to implement, using a spatial quantile regression, is currently being investigated, which would also allow the introduction of further covariates, essential as the effects of climate change are incorporated into estimation procedures.

  11. High Energy Ion Acceleration by Extreme Laser Radiation Pressure

    Science.gov (United States)

    2017-03-14

    published in the internationally leading journal Physical Review Letters. We continued to progress this pionee 15.  SUBJECT TERMS ion therapy, heavy ion ...Thomson parabola spectrometer: To separate and provide a measurement of the charge -to-mass ratio and energy spectrum of the different ion species...AFRL-AFOSR-UK-TR-2017-0015 High energy ion acceleration by extreme laser radiation pressure Paul McKenna UNIVERSITY OF STRATHCLYDE VIZ ROYAL COLLEGE

  12. Liquid Water Restricts Habitability in Extreme Deserts.

    Science.gov (United States)

    Cockell, Charles S; Brown, Sarah; Landenmark, Hanna; Samuels, Toby; Siddall, Rebecca; Wadsworth, Jennifer

    2017-04-01

    Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than more extreme arid deserts where organisms can dehydrate prior to being exposed to these extremes, thus minimizing thermal and radiation damage. Life in extreme deserts is poised between the deleterious effects of the presence and the lack of liquid water. Key Words: Deserts-Extremophiles-Stress-High temperatures-UV radiation-Desiccation. Astrobiology 17, 309-318.

  13. Pharmacological Correction of the Human Functional State in High Altitude Conditions

    Science.gov (United States)

    2001-06-01

    Operational Medical Issues in Hypo-and Hyperbaric Conditions [les Questions medicales a caractere oprationel liees aux conditions hypobares ou hyperbares ...Cholesterol, Adaptation Paper presented at the RTO HFM Symposium on "Operational Medical Issues in Hypo- and Hyperbaric Conditions", held in Toronto...T.D., 1986, Recovery after Extreme Hypobaric Hypoxia as a Method of Study of Antihypoxic Activity of Chemical Compounds. In: Farmakologicheskaya

  14. Analyses of crystal field and exchange interaction of Dy3Ga5O12 under extreme conditions

    International Nuclear Information System (INIS)

    Wang Wei; Qi Xin; Yue Yuan

    2011-01-01

    This paper theoretically investigates the effects of crystal field and exchange interaction field on magnetic properties in dysprosium gallium garnet under extreme conditions (low temperatures and high magnetic fields) based on quantum theory. Here, five sets of crystal field parameters are discussed and compared. It demonstrates that, only considering the crystal field effect, the experiments can not be successfully explained. Thus, referring to the molecular field theory, an effective exchange field associated with the Dy—Dy exchange interaction is further taken into account. Under special consideration of crystal field and the exchange interaction field, it obtains an excellent agreement between the theoretical results and experiments, and further confirms that the exchange interaction field between rare-earth ions has great importance to magnetic properties in paramagnetic rare-earth gallium garnets. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  15. A web-based study of bipolarity and impulsivity in athletes engaging in extreme and high-risk sports.

    Science.gov (United States)

    Dudek, Dominika; Siwek, Marcin; Jaeschke, Rafał; Drozdowicz, Katarzyna; Styczeń, Krzysztof; Arciszewska, Aleksandra; Chrobak, Adrian A; Rybakowski, Janusz K

    2016-06-01

    We hypothesised that men and women who engage in extreme or high-risk sports would score higher on standardised measures of bipolarity and impulsivity compared to age and gender matched controls. Four-hundred and eighty extreme or high-risk athletes (255 males and 225 females) and 235 age-matched control persons (107 males and 128 females) were enrolled into the web-based case-control study. The Mood Disorder Questionnaire (MDQ) and Barratt Impulsiveness Scale (BIS-11) were administered to screen for bipolarity and impulsive behaviours, respectively. Results indicated that extreme or high-risk athletes had significantly higher scores of bipolarity and impulsivity, and lower scores on cognitive complexity of the BIS-11, compared to controls. Further, there were positive correlations between the MDQ and BIS-11 scores. These results showed greater rates of bipolarity and impulsivity, in the extreme or high-risk athletes, suggesting these measures are sensitive to high-risk behaviours.

  16. Impacts of Extreme Events on Human Health. Chapter 4

    Science.gov (United States)

    Bell, Jesse E.; Herring, Stephanie C.; Jantarasami, Lesley; Adrianopoli, Carl; Benedict, Kaitlin; Conlon, Kathryn; Escobar, Vanessa; Hess, Jeremy; Luvall, Jeffrey; Garcia-Pando, Carlos Perez; hide

    2016-01-01

    Increased Exposure to Extreme Events Key Finding 1: Health impacts associated with climate-related changes in exposure to extreme events include death, injury, or illness; exacerbation of underlying medical conditions; and adverse effects on mental health[High Confidence]. Climate change will increase exposure risk in some regions of the United States due to projected increases in the frequency and/or intensity of drought, wildfires, and flooding related to extreme precipitation and hurricanes [Medium Confidence].Disruption of Essential Infrastructure Key Finding 2: Many types of extreme events related to climate change cause disruption of infrastructure, including power, water, transportation, and communication systems, that are essential to maintaining access to health care and emergency response services and safeguarding human health [High Confidence].Vulnerability to Coastal Flooding Key Finding 3: Coastal populations with greater vulnerability to health impacts from coastal flooding include persons with disabilities or other access and functional needs, certain populations of color, older adults, pregnant women and children, low-income populations, and some occupational groups [High Confidence].Climate change will increase exposure risk to coastal flooding due to increases in extreme precipitation and in hurricane intensity and rainfall rates, as well as sea level rise and the resulting increases in storm surge.

  17. Effects of Extreme Temperatures on Cause-Specific Cardiovascular Mortality in China

    Directory of Open Access Journals (Sweden)

    Xuying Wang

    2015-12-01

    Full Text Available Objective: Limited evidence is available for the effects of extreme temperatures on cause-specific cardiovascular mortality in China. Methods: We collected data from Beijing and Shanghai, China, during 2007–2009, including the daily mortality of cardiovascular disease, cerebrovascular disease, ischemic heart disease and hypertensive disease, as well as air pollution concentrations and weather conditions. We used Poisson regression with a distributed lag non-linear model to examine the effects of extremely high and low ambient temperatures on cause-specific cardiovascular mortality. Results: For all cause-specific cardiovascular mortality, Beijing had stronger cold and hot effects than those in Shanghai. The cold effects on cause-specific cardiovascular mortality reached the strongest at lag 0–27, while the hot effects reached the strongest at lag 0–14. The effects of extremely low and high temperatures differed by mortality types in the two cities. Hypertensive disease in Beijing was particularly susceptible to both extremely high and low temperatures; while for Shanghai, people with ischemic heart disease showed the greatest relative risk (RRs = 1.16, 95% CI: 1.03, 1.34 to extremely low temperature. Conclusion: People with hypertensive disease were particularly susceptible to extremely low and high temperatures in Beijing. People with ischemic heart disease in Shanghai showed greater susceptibility to extremely cold days.

  18. Evaluation of BICRON NE MCP DXT-RAD passive extremity dosemeter

    CERN Document Server

    Yuen, P S; Frketich, G; Rotunda, J

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of ligh...

  19. Baryon number nonconservation in extreme conditions

    International Nuclear Information System (INIS)

    Matveev, V.A.; Rubakov, V.A.; Tavkhelidze, A.N.; Shaposhnikov, M.E.

    1988-01-01

    In gauge theories with the left-right asymmetric fermionic content (e.g. in standard electroweak theory) fermion number F is not conserved due to the anomaly. It is shown that anomalous processes, while being exponentially suppressed, under normal conditions, are in fact rapid. The mechanism of fermionic number nonconservation connected with a level crossing phenomenon in external gauge fields is described. The theory and experimental consequences of monopole catalysis of a proton decay is reviewed. It is shown that cold dense fermionic matter is stable only up to some limiting density. It is demonstrated that there is no exponential suppression of the rate F nonconservation at high temperatures. The cosmological implications of this fact are discussed. The strong anomalous fermionic number violation in decays of superheavy fermions technibaryons is considered

  20. The near-term prediction of drought and flooding conditions in the northeastern United States based on extreme phases of AMO and NAO

    Science.gov (United States)

    Berton, Rouzbeh; Driscoll, Charles T.; Adamowski, Jan F.

    2017-10-01

    frequency of wet, average, and dry discharge conditions with regards to the extreme phases of AMO and NAO. While the function was decaying, the tail asymptotically merged into and stabilized at the theoretical probability of the event. As the basin scale increased, the probability of wet, average, and dry discharge conditions decreased. The Merrimack River watershed will most likely experience greater than average discharge as its extreme condition, therefore development should be avoided on flood plains. Furthermore, the current reservoir storage capacity in the Merrimack should be improved in order to accommodate excess water input and minimize flood damage. Future research should target changes in the magnitude and timing of high discharge events in order to develop adaptation strategies for aging hydraulic infrastructure in the region.

  1. A genome-wide analysis of putative functional and exonic variation associated with extremely high intelligence.

    Science.gov (United States)

    Spain, S L; Pedroso, I; Kadeva, N; Miller, M B; Iacono, W G; McGue, M; Stergiakouli, E; Davey Smith, G; Putallaz, M; Lubinski, D; Meaburn, E L; Plomin, R; Simpson, M A

    2016-08-01

    Although individual differences in intelligence (general cognitive ability) are highly heritable, molecular genetic analyses to date have had limited success in identifying specific loci responsible for its heritability. This study is the first to investigate exome variation in individuals of extremely high intelligence. Under the quantitative genetic model, sampling from the high extreme of the distribution should provide increased power to detect associations. We therefore performed a case-control association analysis with 1409 individuals drawn from the top 0.0003 (IQ >170) of the population distribution of intelligence and 3253 unselected population-based controls. Our analysis focused on putative functional exonic variants assayed on the Illumina HumanExome BeadChip. We did not observe any individual protein-altering variants that are reproducibly associated with extremely high intelligence and within the entire distribution of intelligence. Moreover, no significant associations were found for multiple rare alleles within individual genes. However, analyses using genome-wide similarity between unrelated individuals (genome-wide complex trait analysis) indicate that the genotyped functional protein-altering variation yields a heritability estimate of 17.4% (s.e. 1.7%) based on a liability model. In addition, investigation of nominally significant associations revealed fewer rare alleles associated with extremely high intelligence than would be expected under the null hypothesis. This observation is consistent with the hypothesis that rare functional alleles are more frequently detrimental than beneficial to intelligence.

  2. Hemoglobin system of Sparus aurata: Changes in fishes farmed under extreme conditions

    International Nuclear Information System (INIS)

    Campo, Salvatore; Nastasi, Giancarlo; D'Ascola, Angela; Campo, Giuseppe M.; Avenoso, Angela; Traina, Paola; Calatroni, Alberto; Burrascano, Emanuele; Ferlazzo, Alida; Lupidi, Giulio; Gabbianelli, Rosita; Falcioni, Giancarlo

    2008-01-01

    In order to gain more knowledge on the stress responses of gilhead seabream (Sparus aurata) under extreme conditions, this study investigated the functional properties of the hemoglobin system and globin gene expression under hypoxia and low salinity. The oxygen affinity for the two hemoglobin components present inside the S. aurata erythrocyte was practically identical as was the influence of protons and organic phosphates (Root effect). The quantification of S. aurata hemoglobin fractions performed by HPLC and the data on gene expression of globin chains assayed by PCR indicate that under hypoxia and low salinity there is a change in the ratio between the two different hemoglobin components. The result indicating that the distinct hemoglobins present in S. aurata erythrocyte have almost identical functional properties, does not explain the adaptive response (expression change) following exposure of the animal to hypoxia or low salinity on the basis of their function as oxygen transporter. We hypothesize that other parallel biological functions that the hemoglobin molecule is known to display within the erythrocyte are involved in adaptive molecular mechanisms. The autoxidation-reduction cycle of hemoglobin could be involved in the response to particular living conditions

  3. Impact of soil moisture on extreme maximum temperatures in Europe

    Directory of Open Access Journals (Sweden)

    Kirien Whan

    2015-09-01

    Full Text Available Land-atmosphere interactions play an important role for hot temperature extremes in Europe. Dry soils may amplify such extremes through feedbacks with evapotranspiration. While previous observational studies generally focused on the relationship between precipitation deficits and the number of hot days, we investigate here the influence of soil moisture (SM on summer monthly maximum temperatures (TXx using water balance model-based SM estimates (driven with observations and temperature observations. Generalized extreme value distributions are fitted to TXx using SM as a covariate. We identify a negative relationship between SM and TXx, whereby a 100 mm decrease in model-based SM is associated with a 1.6 °C increase in TXx in Southern-Central and Southeastern Europe. Dry SM conditions result in a 2–4 °C increase in the 20-year return value of TXx compared to wet conditions in these two regions. In contrast with SM impacts on the number of hot days (NHD, where low and high surface-moisture conditions lead to different variability, we find a mostly linear dependency of the 20-year return value on surface-moisture conditions. We attribute this difference to the non-linear relationship between TXx and NHD that stems from the threshold-based calculation of NHD. Furthermore the employed SM data and the Standardized Precipitation Index (SPI are only weakly correlated in the investigated regions, highlighting the importance of evapotranspiration and runoff for resulting SM. Finally, in a case study for the hot 2003 summer we illustrate that if 2003 spring conditions in Southern-Central Europe had been as dry as in the more recent 2011 event, temperature extremes in summer would have been higher by about 1 °C, further enhancing the already extreme conditions which prevailed in that year.

  4. Directional analysis of extreme winds under mixed climate conditions

    CSIR Research Space (South Africa)

    Kruger, A

    2013-07-01

    Full Text Available Directional statistics provide design engineers with the opportunity to realise considerable cost savings, but these are not yet provided for in the South African standard for wind loading. The development of the directional statistics of extreme...

  5. Fabrication of surfaces with extremely high contact angle hysteresis from polyelectrolyte multilayer.

    Science.gov (United States)

    Wang, Liming; Wei, Jingjing; Su, Zhaohui

    2011-12-20

    High contact angle hysteresis on polyelectrolyte multilayers (PEMs) ion-paired with hydrophobic perfluorooctanoate anions is reported. Both the bilayer number of PEMs and the ionic strength of deposition solutions have significant influence on contact angle hysteresis: higher ionic strength and greater bilayer number cause increased contact angle hysteresis values. The hysteresis values of ~100° were observed on smooth PEMs and pinning of the receding contact line on hydrophilic defects is implicated as the cause of hysteresis. Surface roughness can be used to further tune the contact angle hysteresis on the PEMs. A surface with extremely high contact angle hysteresis of 156° was fabricated when a PEM was deposited on a rough substrate coated with submicrometer scale silica spheres. It was demonstrated that this extremely high value of contact angle hysteresis resulted from the penetration of water into the rough asperities on the substrate. The same substrate hydrophobized by chemical vapor deposition of 1H,1H,2H,2H-perfluorooctyltriethoxysilane exhibits high advancing contact angle and low hysteresis. © 2011 American Chemical Society

  6. Modular SiGe 130 nm Cell Library for Extreme Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA space missions utilizing application-specific integrated circuits (ASICs) under extreme conditions have a critical need for high performance analog cell...

  7. Performance of Chlorella sorokiniana under simulated extreme winter conditions

    NARCIS (Netherlands)

    Cuaresma, M.; Buffing, M.F.; Janssen, M.G.J.; Lobato, C.V.; Wijffels, R.H.

    2012-01-01

    High annual microalgae productivities can only be achieved if solar light is efficiently used through the different seasons. During winter the productivity is low because of the light and temperature conditions. The productivity and photosynthetic efficiency of Chlorella sorokiniana were assessed

  8. Laser waveform control of extreme ultraviolet high harmonics from solids.

    Science.gov (United States)

    You, Yong Sing; Wu, Mengxi; Yin, Yanchun; Chew, Andrew; Ren, Xiaoming; Gholam-Mirzaei, Shima; Browne, Dana A; Chini, Michael; Chang, Zenghu; Schafer, Kenneth J; Gaarde, Mette B; Ghimire, Shambhu

    2017-05-01

    Solid-state high-harmonic sources offer the possibility of compact, high-repetition-rate attosecond light emitters. However, the time structure of high harmonics must be characterized at the sub-cycle level. We use strong two-cycle laser pulses to directly control the time-dependent nonlinear current in single-crystal MgO, leading to the generation of extreme ultraviolet harmonics. We find that harmonics are delayed with respect to each other, yielding an atto-chirp, the value of which depends on the laser field strength. Our results provide the foundation for attosecond pulse metrology based on solid-state harmonics and a new approach to studying sub-cycle dynamics in solids.

  9. Detection of irradiated peppers by viscosity measurement at extremely high pH

    International Nuclear Information System (INIS)

    Hayashi, Toru; Todoriki, Setsuko

    1996-01-01

    The viscosities of aqueous suspensions of irradiated peppers determined after heat gelatinization were influenced by the pH of the suspension to a greater degree than those of unirradiated ones. Viscosity measurement under an extremely alkaline condition (pH 13.8) resulted in a significant different between irradiated peppers and unirradiated ones, irrespective of the planting locality and storage period. All of the pepper samples irradiated at 5 kGy showed viscosity values significantly lower than unirradiated ones. (Author)

  10. Image-based motion compensation for high-resolution extremities cone-beam CT

    Science.gov (United States)

    Sisniega, A.; Stayman, J. W.; Cao, Q.; Yorkston, J.; Siewerdsen, J. H.; Zbijewski, W.

    2016-03-01

    Purpose: Cone-beam CT (CBCT) of the extremities provides high spatial resolution, but its quantitative accuracy may be challenged by involuntary sub-mm patient motion that cannot be eliminated with simple means of external immobilization. We investigate a two-step iterative motion compensation based on a multi-component metric of image sharpness. Methods: Motion is considered with respect to locally rigid motion within a particular region of interest, and the method supports application to multiple locally rigid regions. Motion is estimated by maximizing a cost function with three components: a gradient metric encouraging image sharpness, an entropy term that favors high contrast and penalizes streaks, and a penalty term encouraging smooth motion. Motion compensation involved initial coarse estimation of gross motion followed by estimation of fine-scale displacements using high resolution reconstructions. The method was evaluated in simulations with synthetic motion (1-4 mm) applied to a wrist volume obtained on a CMOS-based CBCT testbench. Structural similarity index (SSIM) quantified the agreement between motion-compensated and static data. The algorithm was also tested on a motion contaminated patient scan from dedicated extremities CBCT. Results: Excellent correction was achieved for the investigated range of displacements, indicated by good visual agreement with the static data. 10-15% improvement in SSIM was attained for 2-4 mm motions. The compensation was robust against increasing motion (4% decrease in SSIM across the investigated range, compared to 14% with no compensation). Consistent performance was achieved across a range of noise levels. Significant mitigation of artifacts was shown in patient data. Conclusion: The results indicate feasibility of image-based motion correction in extremities CBCT without the need for a priori motion models, external trackers, or fiducials.

  11. PREDICTION OF THE EXTREMAL SHAPE FACTOR OF SPHEROIDAL PARTICLES

    Directory of Open Access Journals (Sweden)

    Daniel Hlubinka

    2011-05-01

    Full Text Available In the stereological unfolding problem for spheroidal particles the extremal shape factor is predicted. The theory of extreme values has been used to show that extremes of the planar shape factor of particle sections tend to the same limit distribution as extremes of the original shape factor for both the conditional and marginal distribution. Attention is then paid to the extreme shape factor conditioned by the particle size. Normalizing constants are evaluated for a parametric model and the numerical procedure is tested on real data from metallography.

  12. Quadrupole beam-transport experiment for heavy ions under extreme space charge conditions

    International Nuclear Information System (INIS)

    Chupp, W.; Faltens, A.; Hartwig, E.C.

    1983-03-01

    A Cs ion-beam-transport experiment is in progress to study beam behavior under extreme space-charge conditions. A five-lens section matches the beam into a periodic electrostatic quadrupole FODO channel and its behavior is found to agree with predictions. With the available parameters (less than or equal to 200 keV, less than or equal to 20 mA, πepsilon/sub n/ greater than or equal to 10 - 7 π rad-m, up to 41 periods) the transverse (betatron) occillation frequency (nu) can be depressed down to one-tenth of its zero current value (nu/sub 0/), where nu/sup 2/ = nu/sub 0//sup 2/ -#betta#/sub p/ 2 /2, and #betta#/sub p/ is the beam plasma frequency. The current can be controlled by adjustment of the gun and the emittance can be controlled independently by means of a set of charged grids

  13. Recent studies of transplutonium compounds: new directions and use of extreme conditions

    International Nuclear Information System (INIS)

    Peterson, J.R.; Begun, G.M.; Gibson, J.K.

    1987-01-01

    The number of bulk-phase compounds prepared and characterized for each of the transplutonium (TPu) elements drops off precipitously with increasing atomic number. However, efforts have been made to increase the number of TPu compounds known and also the range of investigative methods applied to their characterization. The results of a worldwide survey to determine the status of the preparation of new TPu compounds and/or the application of new investigative techniques to the study of such compounds in bulk will be presented. The focus will then shift to Oak Ridge projects: extreme conditions of pressure and/or temperature are being used for synthesis and for absorption and raman spectral studies; single crystals of trihalides are being grown for spectral and magnetic studies; new ternary chalcogenide-halide compounds are being characterized; vaporization thermodynamics of TPu compounds are being determined; and attempts to stabilize unusual oxidation states are being carried out

  14. Highly Efficient Method for the Synthesis of Activated Mesoporous Biocarbons with Extremely High Surface Area for High-Pressure CO2 Adsorption.

    Science.gov (United States)

    Singh, Gurwinder; Lakhi, Kripal S; Kim, In Young; Kim, Sungho; Srivastava, Prashant; Naidu, Ravi; Vinu, Ajayan

    2017-09-06

    A simple and efficient way to synthesize activated mesoporous biocarbons (AMBs) with extremely high BET surface area and large pore volume has been achieved for the first time through a simple solid state activation of freely available biomass, Arundo donax, with zinc chloride. The textural parameters of the AMB can easily be controlled by varying the activation temperature. It is demonstrated that the mesoporosity of AMB can be finely tuned with a simple adjustment of the amount of activating agent. AMB with almost 100% mesoporosity can be achieved using the activating agent and the biomass ratio of 5 and carbonization at 500 °C. Under the optimized conditions, AMB with a BET surface area of 3298 m 2 g -1 and a pore volume of 1.9 cm 3 g -1 can be prepared. While being used as an adsorbent for CO 2 capture, AMB registers an impressively high pressure CO 2 adsorption capacity of 30.2 mmol g -1 at 30 bar which is much higher than that of activated carbon (AC), multiwalled carbon nanotubes (MWCNTs), highly ordered mesoporous carbons, and mesoporous carbon nitrides. AMB also shows high stability with excellent regeneration properties under vacuum and temperatures of up to 250 °C. These impressive textural parameters and high CO 2 adsorption capacity of AMB clearly reveal its potential as a promising adsorbent for high-pressure CO 2 capture and storage application. Also, the simple one-step synthesis strategy outlined in this work would provide a pathway to generate a series of novel mesoporous activated biocarbons from different biomasses.

  15. Extreme climate, not extreme weather: the summer of 1816 in Geneva, Switzerland

    Directory of Open Access Journals (Sweden)

    R. Auchmann

    2012-02-01

    Full Text Available We analyze weather and climate during the "Year without Summer" 1816 using sub-daily data from Geneva, Switzerland, representing one of the climatically most severely affected regions. The record includes twice daily measurements and observations of air temperature, pressure, cloud cover, wind speed, and wind direction as well as daily measurements of precipitation. Comparing 1816 to a contemporary reference period (1799–1821 reveals that the coldness of the summer of 1816 was most prominent in the afternoon, with a shift of the entire distribution function of temperature anomalies by 3–4 °C. Early morning temperature anomalies show a smaller change for the mean, a significant decrease in the variability, and no changes in negative extremes. Analyzing cloudy and cloud-free conditions separately suggests that an increase in the number of cloudy days was to a significant extent responsible for these features. A daily weather type classification based on pressure, pressure tendency, and wind direction shows extremely anomalous frequencies in summer 1816, with only one day (compared to 20 in an average summer classified as high-pressure situation but a tripling of low-pressure situations. The afternoon temperature anomalies expected from only a change in weather types was much stronger negative in summer 1816 than in any other year. For precipitation, our analysis shows that the 80% increase in summer precipitation compared to the reference period can be explained by 80% increase in the frequency of precipitation, while no change could be found neither in the average intensity of precipitation nor in the frequency distribution of extreme precipitation. In all, the analysis shows that the regional circulation and local cloud cover played a dominant role. It also shows that the summer of 1816 was an example of extreme climate, not extreme weather.

  16. The greenhouse effect and extreme weather

    International Nuclear Information System (INIS)

    Groenaas, Sigbjoern; Kvamstoe, Nils Gunnar

    2002-01-01

    The article asserts that an anthropogenic global warming is occurring. This greenhouse effect is expected to cause more occurrences of extreme weather. It is extremely difficult, however, to relate specific weather catastrophes to global warming with certainty, since such extreme weather conditions are rare historically. The subject is controversial. The article also discusses the public debate and the risk of floods

  17. Hydrogen ion induced ultralow wear of PEEK under extreme load

    Science.gov (United States)

    Yan, Shuai; Wang, Anying; Fei, Jixiong; Wang, Zhenyang; Zhang, Xiaofeng; Lin, Bin

    2018-03-01

    As a high-performance engineering polymer, poly(ether ether ketone) (PEEK) is a perfect candidate material for applications under extreme working conditions. However, its high wear rate greatly shortens its service life. In this study, ultralow friction and wear between PEEK and silicon nitride (Si3N4) under extreme-load conditions (with a mean contact pressure above 100 MPa) are found in acid lubricating solutions. Both friction and wear decrease sharply with decreasing pH. At pH = 1, the friction coefficient decreases by an order of magnitude and the wear rate of the PEEK decreases by two orders of magnitude compared to the results with water lubrication. These reductions in friction and wear occur for different speed, load, and surface roughness conditions. The underlying mechanism can be attributed to the formation of hydrogen-ion-induced electrical double layers on the surfaces of PEEK and Si3N4. The combined effect of the resulting repulsive force, electro-viscosity, and low shear strength of the water layer dramatically reduces both friction and wear.

  18. An Extreme Degree of Difficulty: The Educational Demographics of Urban Neighborhood High Schools

    Science.gov (United States)

    Neild, Ruth Curran; Balfanz, Robert

    2006-01-01

    Despite the growth of a variety of alternatives to the neighborhood high school, most students in big-city school systems still attend large comprehensive high schools that serve a particular residential area. The authors contend that the extreme concentration of educational need at these schools is often overlooked by policymakers, school reform…

  19. Acclimatization to extreme heat

    Science.gov (United States)

    Warner, M. E.; Ganguly, A. R.; Bhatia, U.

    2017-12-01

    Heat extremes throughout the globe, as well as in the United States, are expected to increase. These heat extremes have been shown to impact human health, resulting in some of the highest levels of lives lost as compared with similar natural disasters. But in order to inform decision makers and best understand future mortality and morbidity, adaptation and mitigation must be considered. Defined as the ability for individuals or society to change behavior and/or adapt physiologically, acclimatization encompasses the gradual adaptation that occurs over time. Therefore, this research aims to account for acclimatization to extreme heat by using a hybrid methodology that incorporates future air conditioning use and installation patterns with future temperature-related time series data. While previous studies have not accounted for energy usage patterns and market saturation scenarios, we integrate such factors to compare the impact of air conditioning as a tool for acclimatization, with a particular emphasis on mortality within vulnerable communities.

  20. Extreme value modelling of Ghana stock exchange index.

    Science.gov (United States)

    Nortey, Ezekiel N N; Asare, Kwabena; Mettle, Felix Okoe

    2015-01-01

    Modelling of extreme events has always been of interest in fields such as hydrology and meteorology. However, after the recent global financial crises, appropriate models for modelling of such rare events leading to these crises have become quite essential in the finance and risk management fields. This paper models the extreme values of the Ghana stock exchange all-shares index (2000-2010) by applying the extreme value theory (EVT) to fit a model to the tails of the daily stock returns data. A conditional approach of the EVT was preferred and hence an ARMA-GARCH model was fitted to the data to correct for the effects of autocorrelation and conditional heteroscedastic terms present in the returns series, before the EVT method was applied. The Peak Over Threshold approach of the EVT, which fits a Generalized Pareto Distribution (GPD) model to excesses above a certain selected threshold, was employed. Maximum likelihood estimates of the model parameters were obtained and the model's goodness of fit was assessed graphically using Q-Q, P-P and density plots. The findings indicate that the GPD provides an adequate fit to the data of excesses. The size of the extreme daily Ghanaian stock market movements were then computed using the value at risk and expected shortfall risk measures at some high quantiles, based on the fitted GPD model.

  1. Unique Nature of the Quality of Life in the Context of Extreme Climatic, Geographical and Specific Socio-Cultural Living Conditions

    Science.gov (United States)

    Kulik, Anastasia; Neyaskina, Yuliya; Frizen, Marina; Shiryaeva, Olga; Surikova, Yana

    2016-01-01

    This article presents the results of a detailed empirical research, aimed at studying the quality of life in the context of extreme climatic, geographical and specific sociocultural living conditions. Our research is based on the methodological approach including social, economical, ecological and psychological characteristics and reflecting…

  2. Extremely high wall-shear stress events in a turbulent boundary layer

    Science.gov (United States)

    Pan, Chong; Kwon, Yongseok

    2018-04-01

    The present work studies the fluctuating characteristics of the streamwise wall-shear stress in a DNS of a turbulent boundary layer at Re τ =1500 from a structural view. The two-dimensional field of the fluctuating friction velocity u‧ τ (x,z) is decomposed into the large- and small-scale components via a recently proposed scale separation algorithm, Quasi-bivariate Variational Mode Decomposition (QB-VMD). Both components are found to be dominated by streak-like structures, which can be regarded as the wall signature of the inner-layer streaks and the outer-layer LSMs, respectively. Extreme positive/negative wall-shear stress fluctuation events are detected in the large-scale component. The former’s occurrence frequency is nearly one order of magnitude higher than the latter; therefore, they contribute a significant portion of the long tail of the wall-shear stress distribution. Both two-point correlations and conditional averages show that these extreme positive wall-shear stress events are embedded in the large-scale positive u‧ τ streaks. They seem to be formed by near-wall ‘splatting’ process, which are related to strong finger-like sweeping (Q4) events originated from the outer-layer positive LSMs.

  3. Potential changes in the extreme climate conditions at the regional scale: from observed data to modelling approaches and towards probabilistic climate change information

    International Nuclear Information System (INIS)

    Gachon, P.; Radojevic, M.; Harding, A.; Saad, C.; Nguyen, V.T.V.

    2008-01-01

    The changes in the characteristics of extreme climate conditions are one of the most critical challenges for all ecosystems, human being and infrastructure, in the context of the on-going global climate change. However, extremes information needed for impacts studies cannot be obtained directly from coarse scale global climate models (GCMs), due mainly to their difficulties to incorporate regional scale feedbacks and processes responsible in part for the occurrence, intensity and duration of extreme events. Downscaling approaches, namely statistical and dynamical downscaling techniques (i.e. SD and RCM), have emerged as useful tools to develop high resolution climate change information, in particular for extremes, as those are theoretically more capable to take into account regional/local forcings and their feedbacks from large scale influences as they are driven with GCM synoptic variables. Nevertheless, in spite of the potential added values from downscaling methods (statistical and dynamical), a rigorous assessment of these methods are needed as inherent difficulties to simulate extremes are still present. In this paper, different series of RCM and SD simulations using three different GCMs are presented and evaluated with respect to observed values over the current period and over a river basin in southern Quebec, with future ensemble runs, i.e. centered over 2050s (i.e. 2041-2070 period using the SRES A2 emission scenario). Results suggest that the downscaling performance over the baseline period significantly varies between the two downscaling techniques and over various seasons with more regular reliable simulated values with SD technique for temperature than for RCM runs, while both approaches produced quite similar temperature changes in the future from median values with more divergence for extremes. For precipitation, less accurate information is obtained compared to observed data, and with more differences among models with higher uncertainties in the

  4. Adjuvant radiotherapy in high-grade extremity sarcomas

    International Nuclear Information System (INIS)

    Franca, Carlos Antonio da Silva; Penna, Antonio Belmiro Rodrigues Campbell; Carvalho, Antonio Carlos Pires; Vieira, Sergio Lannes

    2010-01-01

    Objective: to evaluate the therapies utilized in the authors' institution for management of high-grade extremity sarcomas, analyzing the overall survival rates following multidisciplinary treatment. Materials and methods: retrospective study developed in the period from 1993 to 2007 with 36 patients diagnosed with stages IIb/III, submitted to postoperative external beam radiotherapy, with or without boost dose, utilizing high-dose brachytherapy. Results: thirty-six patients underwent surgery followed by adjuvant external beam radiation therapy. Four patients (11%) received boost dose with brachytherapy, and seven (19%) received chemotherapy. The average dose for radiotherapy was 50 Gy (CI 95%: 47-53 Gy), and the four patients with brachytherapy boost received doses ranging from 16.2 to 35 Gy. Chemotherapy was indicated for seven patients (19%) with positive margins. Fifteen patients (42%) presented local or distant recurrence, and all of them progressed to death. Twenty-one patients (58%) remain with no clinical/radiological evidence of local/distant recurrence. The mean follow-up time was 88 months (IC 95%: 74-102). The overall seven years survival rate was 80%. Conclusion: combined surgery and radiotherapy is an effective treatment with excellent outcomes in cases where brachytherapy is associated, with improved overall survival rates. (author)

  5. Reliability of offshore wind power production under extreme wind conditions. Deliverable D 9.5. Work Package 9: Electrical grid

    DEFF Research Database (Denmark)

    Cutululis, Nicolaos Antonio; Zeni, Lorenzo

    years, with each year simulated with five random seeds, leading to a total of 25 annual wind power time series for six large offshore wind farms, summing up to a little over 330 wind turbines. Two storm control strategies were used. The analysis involved several aspects inspired from reliability studies....... The aspects investigated are storm events occurrences and durations, storm control strategy impact on the capacity factor (lost production), the loss of production (power produced from wind drops below a certain threshold due to high wind speeds and storm controller) and finally, the wind power production......Reliability of offshore wind production under extreme wind conditions was investigated in this report. The wind power variability from existing and future large offshore wind farms in Western Denmark were simulated using the Correlated Wind model developed at Risø. The analysis was done for five...

  6. The genomic sequence of Exiguobacterium chiriqhucha str. N139 reveals a species that thrives in cold waters and extreme environmental conditions

    Directory of Open Access Journals (Sweden)

    Ana Gutiérrez-Preciado

    2017-04-01

    Full Text Available We report the genome sequence of Exiguobacterium chiriqhucha str. N139, isolated from a high-altitude Andean lake. Comparative genomic analyses of the Exiguobacterium genomes available suggest that our strain belongs to the same species as the previously reported E. pavilionensis str. RW-2 and Exiguobacterium str. GIC 31. We describe this species and propose the chiriqhucha name to group them. ‘Chiri qhucha’ in Quechua means ‘cold lake’, which is a common origin of these three cosmopolitan Exiguobacteria. The 2,952,588-bp E. chiriqhucha str. N139 genome contains one chromosome and three megaplasmids. The genome analysis of the Andean strain suggests the presence of enzymes that confer E. chiriqhucha str. N139 the ability to grow under multiple environmental extreme conditions, including high concentrations of different metals, high ultraviolet B radiation, scavenging for phosphorous and coping with high salinity. Moreover, the regulation of its tryptophan biosynthesis suggests that novel pathways remain to be discovered, and that these pathways might be fundamental in the amino acid metabolism of the microbial community from Laguna Negra, Argentina.

  7. Extreme wildfire events are linked to global-change-type droughts in the northern Mediterranean

    Science.gov (United States)

    Ruffault, Julien; Curt, Thomas; Martin-StPaul, Nicolas K.; Moron, Vincent; Trigo, Ricardo M.

    2018-03-01

    Increasing drought conditions under global warming are expected to alter the frequency and distribution of large and high-intensity wildfires. However, our understanding of the impact of increasing drought on extreme wildfires events remains incomplete. Here, we analyzed the weather conditions associated with the extreme wildfires events that occurred in Mediterranean France during the exceptionally dry summers of 2003 and 2016. We identified that these fires were related to two distinct shifts in the fire weather space towards fire weather conditions that had not been explored before and resulting from specific interactions between different types of drought and different fire weather types. In 2016, a long-lasting press drought intensified wind-driven fires. In 2003, a hot drought combining a heat wave with a press drought intensified heat-induced fires. Our findings highlight that increasing drought conditions projected by climate change scenarios might affect the dryness of fuel compartments and lead to a higher frequency of extremes wildfires events.

  8. Hydrogen at extreme pressures (Review Article)

    International Nuclear Information System (INIS)

    Goncharov, Alexander F.; Howie, Ross T.; Gregoryanz Eugene

    2013-01-01

    Here we review recent experimental and theoretical studies of hydrogen approaching metallization regime. Experimental techniques have made great advances over the last several years making it possible to reach previously unachievable conditions of pressure and temperature and to probe hydrogen at these conditions. Theoretical methods have also greatly improved; exemplified through the prediction of new structural and ordered quantum states. Recently, a new solid phase of hydrogen, phase IV, has been discovered in a high-pressure high-temperature domain. This phase is quite unusual structurally and chemically as it represents an intermediate state between common molecular and monatomic configurations. Moreover, it shows remarkable fluxional characteristics related to its quantum nature, which makes it unique among the solid phases, even of light elements. However, phase IV shows the presence of a band gap and exhibits distinct phonon and libron characteristic of classical solids. The quantum behavior of hydrogen in the limit of very high pressure remains an open question. Prospects of studying hydrogen at more extreme conditions by static and combined static-dynamic methods are also presented.

  9. Extreme fire events are related to previous-year surface moisture conditions in permafrost-underlain larch forests of Siberia

    International Nuclear Information System (INIS)

    Forkel, Matthias; Beer, Christian; Thonicke, Kirsten; Cramer, Wolfgang; Bartalev, Sergey; Schmullius, Christiane

    2012-01-01

    Wildfires are a natural and important element in the functioning of boreal forests. However, in some years, fires with extreme spread and severity occur. Such severe fires can degrade the forest, affect human values, emit huge amounts of carbon and aerosols and alter the land surface albedo. Usually, wind, slope and dry air conditions have been recognized as factors determining fire spread. Here we identify surface moisture as an additional important driving factor for the evolution of extreme fire events in the Baikal region. An area of 127 000 km 2 burned in this region in 2003, a large part of it in regions underlain by permafrost. Analyses of satellite data for 2002–2009 indicate that previous-summer surface moisture is a better predictor for burned area than precipitation anomalies or fire weather indices for larch forests with continuous permafrost. Our analysis advances the understanding of complex interactions between the atmosphere, vegetation and soil, and how coupled mechanisms can lead to extreme events. These findings emphasize the importance of a mechanistic coupling of soil thermodynamics, hydrology, vegetation functioning, and fire activity in Earth system models for projecting climate change impacts over the next century. (letter)

  10. Comparison and development of advanced dosimetric techniques to be used under extreme climatic conditions

    International Nuclear Information System (INIS)

    Madhvanath, U.

    1975-08-01

    The post-irradiation fading characteristics of various dosimeters in function of relative humidity of air during storage were tested in specially set up humidity boxes. The temperature and relative humidity were varied between 5deg-35degC and 40-90%, respectively. Fading was 70% and 80% at 2 and 6 days respectively, for Kodak Type 2 film under 28degC and 76% relative humidity. Under these conditions the corresponding values for NTA emulsions were 30% and 80% respectively. Agfa-Gevaert films proved to be less sensitive and gave 20% and 30%, respectively, for the mentioned intervals. When Kodak Type 2 film was sealed in polythene bags, fading was reduced considerably, to appr. 15% in 4 weeks. Alternate storage of exposed films in humid and dry conditions also reduced fading to the same extent. When NTA emulsions were double-sealed with desiccant inside fading was reduced to 10% in 15 days. CaSO 4 :Dy (DRP and Harshaw) showed only 7% fading in 3 months. LiF TLD-100 was more sensitive, 13% in 2 months. Gamma-irradiated Li-borate has faded up to 30% at extreme climatic conditions in 3 months but thermal neutron irradiated Li-borate was resistant against fading for this period

  11. Air-cooled LiBr-water absorption chillers for solar air conditioning in extremely hot weathers

    International Nuclear Information System (INIS)

    Kim, D.S.; Infante Ferreira, C.A.

    2009-01-01

    A low temperature-driven absorption cycle is theoretically investigated for the development of an air-cooled LiBr-water absorption chiller to be combined with low-cost flat solar collectors for solar air conditioning in hot and dry regions. The cycle works with dilute LiBr-water solutions so that risk of LiBr crystallization is less than for commercially available water-cooled LiBr-water absorption chillers even in extremely hot ambient conditions. Two-phase heat exchangers in the system were modelled taking account of the heat and mass transfer resistances in falling film flows by applying the film theory in thermal and concentration boundary layers. Both directly and indirectly air-cooled chillers were modelled by properly combining component models and boundary conditions in a matrix system and solved with an algebraic equation solver. Simulation results predict that the chillers would deliver chilled water around 7.0 deg. C with a COP of 0.37 from 90 deg. C hot water under 35 deg. C ambient condition. At 50 deg. C ambient temperature, the chillers retained about 36% of their cooling power at 35 deg. C ambient. Compared with the directly air-cooled chiller, the indirectly air-cooled chiller presented a cooling power performance reduction of about 30%

  12. Kinetics of Materials at Extreme Conditions: Understanding the Time Dependent Approach to Equilibrium at MaRIE

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, R. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mcnabb, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kumar, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Eggert, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Borg, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cerreta, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dattelbaum, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fried, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Greeff, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Stolken, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-04-21

    The National Nuclear Security Agency has recently recognized that a long-term need exists to establish a stronger scientific basis for the assessment and qualification of materials and manufacturing processes for the nuclear stockpile and other national security applications. These materials may have undergone substantial changes with age, or may represent new materials that are being introduced because of difficulties associated with reusing or recreating materials used in original stockpile components. Also, with advancements in manufacturing methods, the NNSA anticipates opportunities for an enhanced range of control over fabricated components, an enhanced pace of materials development, and enhanced functionality. The development of qualification standards for these new materials will require the ability to understand and control material characteristics that affect both mechanical and dynamic performance. A unique aspect for NNSA is that the performance requirements for materials are often set by system hydrodynamics, and these materials must perform in extreme environments and loading conditions. Thus, the scientific motivation is to understand “Matter-Radiation Interactions in Extremes (MaRIE).”

  13. Bias and spread in extreme value theory measurements of probability of error

    Science.gov (United States)

    Smith, J. G.

    1972-01-01

    Extreme value theory is examined to explain the cause of the bias and spread in performance of communications systems characterized by low bit rates and high data reliability requirements, for cases in which underlying noise is Gaussian or perturbed Gaussian. Experimental verification is presented and procedures that minimize these effects are suggested. Even under these conditions, however, extreme value theory test results are not particularly more significant than bit error rate tests.

  14. [Guidelines on asthma in extreme environmental conditions].

    Science.gov (United States)

    Drobnic, Franchek; Borderías Clau, Luis

    2009-01-01

    Asthma is a highly prevalent chronic disease which, if not properly controlled, can limit the patient's activities and lifestyle. In recent decades, owing to the diffusion of educational materials, the application of clinical guidelines and, most importantly, the availability of effective pharmacological treatment, most patients with asthma are now able to lead normal lives. Significant social changes have also taken place during the same period, including more widespread pursuit of sporting activities and tourism. As a result of these changes, individuals with asthma can now participate in certain activities that were inconceivable for these patients only a few years ago, including winter sports, underwater activities, air flight, and travel to remote places with unusual environmental conditions (deserts, high mountain environments, and tropical regions). In spite of the publication of several studies on this subject, our understanding of the effects of these situations on patients with asthma is still limited. The Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) has decided to publish these recommendations based on the available evidence and expert opinion in order to provide information on this topic to both doctors and patients and to avert potentially dangerous situations that could endanger the lives of these patients.

  15. The paradox of extreme high-altitude migration in bar-headed geese Anser indicus

    Science.gov (United States)

    Hawkes, L. A.; Balachandran, S.; Batbayar, N.; Butler, P. J.; Chua, B.; Douglas, D. C.; Frappell, P. B.; Hou, Y.; Milsom, W. K.; Newman, S. H.; Prosser, D. J.; Sathiyaselvam, P.; Scott, G. R.; Takekawa, J. Y.; Natsagdorj, T.; Wikelski, M.; Witt, M. J.; Yan, B.; Bishop, C. M.

    2013-01-01

    Bar-headed geese are renowned for migratory flights at extremely high altitudes over the world's tallest mountains, the Himalayas, where partial pressure of oxygen is dramatically reduced while flight costs, in terms of rate of oxygen consumption, are greatly increased. Such a mismatch is paradoxical, and it is not clear why geese might fly higher than is absolutely necessary. In addition, direct empirical measurements of high-altitude flight are lacking. We test whether migrating bar-headed geese actually minimize flight altitude and make use of favourable winds to reduce flight costs. By tracking 91 geese, we show that these birds typically travel through the valleys of the Himalayas and not over the summits. We report maximum flight altitudes of 7290 m and 6540 m for southbound and northbound geese, respectively, but with 95 per cent of locations received from less than 5489 m. Geese travelled along a route that was 112 km longer than the great circle (shortest distance) route, with transit ground speeds suggesting that they rarely profited from tailwinds. Bar-headed geese from these eastern populations generally travel only as high as the terrain beneath them dictates and rarely in profitable winds. Nevertheless, their migration represents an enormous challenge in conditions where humans and other mammals are only able to operate at levels well below their sea-level maxima. PMID:23118436

  16. Covered Interest-Rate Parity Revisited: an Extreme Value Copula Analysis

    Directory of Open Access Journals (Sweden)

    Mikel Ugando-Peñate

    2015-11-01

    Full Text Available This article studied the covered interest-rate parity (CIP condition under extreme market movements using extreme value theory and extreme value copulas to characterize dependence between extreme interest rate differentials and forward premium. The empirical analysis for the CIP between interest rates for the US dollar and the British pound indicates that there is strong co-movement between interest rate differentials and forward premium at different maturities and in both upper and lower tails. This conclusion would support the existence of the CIP condition under extreme market movements.

  17. High dose rate brachytherapy for the treatment of soft tissue sarcoma of the extremity

    International Nuclear Information System (INIS)

    Speight, J.L.; Streeter, O.E.; Chawla, S.; Menendez, L.E.

    1996-01-01

    Purpose: we examined the role of preoperative neoadjuvant chemoradiation and adjuvant high-dose rate brachytherapy on the management of prognostically unfavorable soft tissue sarcomas of the extremities. Our goal was to examine the effect of high dose rate interstitial brachytherapy (HDR IBT) on reducing the risk of local recurrence following limb-sparing resection, as well as shortening treatment duration. Materials and methods: eleven patients, ranging in age from 31 to 73 years old, with soft tissue sarcoma of the extremity were treated at USC/Norris Comprehensive Cancer Center during 1994 and 1995. All patients had biopsy proven soft tissue sarcoma, and all were suitable candidates for limb-sparing surgery. All lesions were greater than 5cm in size and were primarily high grade. Tumor histologies included malignant fibrous histiocytoma (45%), liposarcoma (18%) and leiomyosarcoma, synovial cell sarcoma and spindle cell sarcoma (36%). Sites of tumor origin were the lower extremity (55%), upper extremity (18%) and buttock (9%), 1 patient (9%) had lesions in both the upper and lower extremity. Patients received HDR IBT following combined chemotherapy and external beam irradiation (EBRT) and en bloc resection of the sarcoma. Neoadjuvant chemotherapy consisted of three to four cycles of either Ifosfamide/Mesna with or without Adriamycin, or Mesna, Adriamycin, Ifosfamide and Dacarbazine. One patient received Cis-platin in addition to Ifos/Adr. A minimum of two cycles of chemotherapy were administered prior to EBRT. Additional cycles of chemotherapy were completed concurrently with EBRT but prior to HDR IBT. Preoperative EBRT doses ranging from 40 to 59.4 Gy were given in daily fractions of 180 to 200cGy. Following en bloc resection, HDR IBT was administered using the Omnitron tm 2000 remote afterloading system. Doses ranging from 13 to 30 Gy were delivered to the surgical tumor bed at depths of 0.5mm to 0.75mm from the radioactive source. Results: median follow-up was

  18. Theoretical and experimental study of single particle tracking in extreme conditions: single photon imaging

    International Nuclear Information System (INIS)

    Cajgfinger, T.

    2012-10-01

    This manuscript presents my thesis on the high frame rate (500 frames / second) single-photon detector electron-bombarded CMOS (ebCMOS). The first section compares three ultra-sensitive detectors and their methods for improving photon sensitivity: the CMOS low noise (sCMOS), the electron-multiplying CCD (emCCD) with signal multiplication by pixel and the ebCMOS with amplification by applied electric field. The method developed to detect single photon impacts with intra-pixel resolution on the ebCMOS sensor is presented. The second section compares the localization accuracy of these detectors in extreme conditions of very low photon flux (<10 photons/frame). First the theoretical limit is calculated using the Cramer-Rao lower bound for significant parameter sets. An experimental comparison of the detectors is then described. The setup provides one or more point sources controlled in position, signal and background noise. The results allow a comparison of the experimental effectiveness, purity and localization accuracy. The last section describes two experiments with the ebCMOS camera. The first aims at tracking hundreds of quantum dots simultaneously at the Nanoptec center. The second focuses on the swimming of bacteria at the surface at the Joliot Curie Institute. The point sources tracking algorithm using single photons and the Kalman filter implementation developed for these experiments is also described. (author)

  19. Modeling Spatial Dependence of Rainfall Extremes Across Multiple Durations

    Science.gov (United States)

    Le, Phuong Dong; Leonard, Michael; Westra, Seth

    2018-03-01

    Determining the probability of a flood event in a catchment given that another flood has occurred in a nearby catchment is useful in the design of infrastructure such as road networks that have multiple river crossings. These conditional flood probabilities can be estimated by calculating conditional probabilities of extreme rainfall and then transforming rainfall to runoff through a hydrologic model. Each catchment's hydrological response times are unlikely to be the same, so in order to estimate these conditional probabilities one must consider the dependence of extreme rainfall both across space and across critical storm durations. To represent these types of dependence, this study proposes a new approach for combining extreme rainfall across different durations within a spatial extreme value model using max-stable process theory. This is achieved in a stepwise manner. The first step defines a set of common parameters for the marginal distributions across multiple durations. The parameters are then spatially interpolated to develop a spatial field. Storm-level dependence is represented through the max-stable process for rainfall extremes across different durations. The dependence model shows a reasonable fit between the observed pairwise extremal coefficients and the theoretical pairwise extremal coefficient function across all durations. The study demonstrates how the approach can be applied to develop conditional maps of the return period and return level across different durations.

  20. Extreme-ultraviolet wavelength and lifetime measurements in highly ionized krypton

    CERN Document Server

    Kukla, K W; Vogt, C M V; Berry, H G; Dunford, R W; Curtis, L J; Cheng, S

    2005-01-01

    We have studied the spectrum of highly ionized krypton in the extreme-ultraviolet wavelength region (50-300 Aa), using beam-foil excitation of fast krypton ions at the Argonne ATLAS accelerator facility. We report measurements of transition wavelengths and excited-state lifetimes for n=2 states in the lithiumlike, berylliumlike, and boronlike ions, Kr/sup 31+,32+,33+/. Excited state lifetimes ranging from 10 ps to 3 ns were measured by acquiring time- of-flight-delayed spectra with a position-sensitive multichannel detector.

  1. Study of a pressure measurement method using laser ionization for extremely-high vacuum

    International Nuclear Information System (INIS)

    Kokubun, Kiyohide

    1991-01-01

    A method of measuring pressures in the range of extremely-high vacuum (XHV) using the laser ionization has been studied. For this purpose, nonresonant multiphoton ionization of various kinds of gases has been studied, and highly-sensitive ion-detection systems and an extremely-high vacuum equipment were fabricated. These results are presented in detail. Two ion-detection systems were fabricated and tested: the one is based on the pulse-counting method, and the other utilizes the image-processing technique. The former is superior in detecting a few ions or less. The latter was processing technique. The former is superior in detecting a few ions or less. The latter was verified to able to count accurately the number of ions in the range of a few to several hundreds. To obtain the information on residual gases and test our pressure measurement system, an extremely-high vacuum system was fabricated in our own fashion, attained a pressure lower than 1 x 10 -10 Pa, measured with an extractor gauge. The outgassing rate of this vacuum vessel was measured to be 7.8 x 10 -11 Pa·m 3 /s·m 2 . The surface structures and the surface compositions of the raw material, the machined material, and the machined-and-outgased material were studied by SEM and AES. Besides, the pumping characteristics and the residual gases of the XHV system were investigated in detail at each pumping stage. On the course of these studies, the method of pressure measurement using the laser-ionization has been verified to be very effective for measuring pressures in XHV. (J.P.N.)

  2. Frequently Asked Questions (FAQ) about Extreme Heat

    Science.gov (United States)

    ... Extreme Heat Older Adults (Aged 65+) Infants and Children Chronic Medical Conditions Low Income Athletes Outdoor Workers Pets Hot Weather Tips Warning Signs and Symptoms FAQs Social Media How to Stay Cool Missouri Cooling Centers Extreme ...

  3. Long-term monitoring reveals cold-water corals in extreme conditions off the southeast US coast

    Science.gov (United States)

    Mienis, F.; Duineveld, G.; Davies, A. J.; Ross, S. W.; Lavaleye, M.; Van Weering, T.

    2011-12-01

    Cold-water corals are common on the SE slope of the US (SEUS) from Florida to Cape Hatteras between depths of 400-600 m. Near Cape Hatteras cold-water corals have formed mound structures that are up to 60 m high, which are mainly covered by living colonies of the coral species Lophelia pertusa. Past explorations of major reef sites of N Carolina using remote and manned submersibles have shown living Lophelia pertusa colonies on the current facing side of the mound structures and a high biodiversity of associated fauna, especially fish. The coral areas lie in the vicinity of the Gulf Stream characterized by strong currents transporting relatively warm water northwards along the SEUS slope. Thus far little is known about the environmental conditions inside the SEUS coral communities and particularly the effects of the nearby Gulf Stream. In December 2009 two autonomous benthic landers were deployed amidst Lophelia reefs off Cape Lookout (NC) for a period of 6 months to define oceanographic patterns that are relevant for the development and persistence of cold-water coral ecosystems. Landers recorded temperature, fluorescence, turbidity, and current speed and direction. Furthermore, a sediment trap was mounted on the landers that collected material at a 16-days interval. A first analysis of the lander data shows that instability of the Gulf Stream causes rapid rises in temperature, current speed and turbidity lasting for days to more than a week. Peak temperature and turbidity levels are the highest measured in coral habitats studied so far. We did not see clear cut effects of Gulf Stream instabilities on the near bed flux of phytodetritus as opposed to reports of meanders inducing upwelling and enhanced production in the photic zone. Data analyzed so far suggest that cwc habitats of Cape Lookout experience extreme and adverse conditions for prolonged periods. The findings of this study are compared with methodologically similar studies that have been conducted in

  4. Extreme conditioning programs and injury risk in a US Army Brigade Combat Team.

    Science.gov (United States)

    Grier, Tyson; Canham-Chervak, Michelle; McNulty, Vancil; Jones, Bruce H

    2013-01-01

    Brigades and battalions throughout the US Army are currently implementing a variety of exercise and conditioning programs with greater focus on preparation for mission-specific tasks. An Army physical therapy clinic working with a light infantry brigade developed the Advanced Tactical Athlete Conditioning (ATAC) program. The ATAC program is a unique physical training program consisting of high-intensity aquatic exercises, tactical agility circuits, combat core conditioning, and interval speed training. Along with ATAC, battalions have also incorporated components of fitness programs such as the Ranger Athlete Warrior program and CrossFit (Crossfit, Inc, Santa Monica, CA) an extreme conditioning program (ECP). To determine if these new programs (ATAC, ECP) had an effect on injury rates and physical fitness. Surveys were administered to collect personal characteristics, tobacco use, personal physical fitness training, Army physical fitness test results, and self-reported injuries. Medical record injury data were obtained 6 months before and 6 months after the implementation of the new program. Predictors of injury risk were assessed using multivariate logistic regression. Odds ratios (OR) and 95% confidence intervals (CI) were reported. Injury incidence among Soldiers increased 12% for overall injuries and 16% for overuse injuries after the implementation of the ATAC/ECPs. However, injury incidence among Soldiers not participating in ATAC/ECPs also increased 14% for overall injuries and 10% for overuse injuries. Risk factors associated with higher injury risk for Soldiers participating in ATAC/ECPs included: greater mileage run per week during unit physical training (OR (>16 miles per week÷≤7 miles per week)=2.24, 95% CI, 1.33-3.80); higher body mass index (BMI) (OR (BMI 25-29.9÷BMI<25)=1.77, 95% CI, 1.29-2.44), (OR (BMI =30÷BMI<25)=2.72, 95% CI, 1.67-4.43); cigarette use (OR (smoker÷nonsmoker)=1.80, 95% CI, 1.34-2.42); poor performance on the 2-mile run during

  5. Extreme climatic events in relation to global change and their impact on life histories

    Directory of Open Access Journals (Sweden)

    Juan MORENO, Anders Pape Møller

    2011-06-01

    Full Text Available Extreme weather conditions occur at an increasing rate as evidenced by higher frequency of hurricanes and more extreme precipitation and temperature anomalies. Such extreme environmental conditions will have important implications for all living organisms through greater frequency of reproductive failure and reduced adult survival. We review examples of reproductive failure and reduced survival related to extreme weather conditions. Phenotypic plasticity may not be sufficient to allow adaptation to extreme weather for many animals. Theory predicts reduced reproductive effort as a response to increased stochasticity. We predict that patterns of natural selection will change towards truncation selection as environmental conditions become more extreme. Such changes in patterns of selection may facilitate adaptation to extreme events. However, effects of selection on reproductive effort are difficult to detect. We present a number of predictions for the effects of extreme weather conditions in need of empirical tests. Finally, we suggest a number of empirical reviews that could improve our ability to judge the effects of extreme environmental conditions on life history [Current Zoology 57 (3: 375–389, 2011].

  6. Assessing changes in extreme convective precipitation from a damage perspective

    Science.gov (United States)

    Schroeer, K.; Tye, M. R.

    2016-12-01

    Projected increases in high-intensity short-duration convective precipitation are expected even in regions that are likely to become more arid. Such high intensity precipitation events can trigger hazardous flash floods, debris flows and landslides that put people and local assets at risk. However, the assessment of local scale precipitation extremes is hampered by its high spatial and temporal variability. In addition to which, not only are extreme events rare, but such small scale events are likely to be underreported where they don't coincide with the observation network. Rather than focus solely on the convective precipitation, understanding the characteristics of these extremes which drive damage may be more effective to assess future risks. Two sources of data are used in this study. First, sub-daily precipitation observations over the Southern Alps enable an examination of seasonal and regional patterns in high-intensity convective precipitation and their relationship with weather types. Secondly, reports of private loss and damage on a household scale are used to identify which events are most damaging, or what conditions potentially enhance the vulnerability to these extremes.This study explores the potential added value from including recorded loss and damage data to understand the risks from summertime convective precipitation events. By relating precipitation generating weather types to the severity of damage we hope to develop a mechanism to assess future risks. A further benefit would be to identify from damage reports the likely occurrence of precipitation extremes where no direct observations are available and use this information to validate remotely sensed observations.

  7. Global patterns of NDVI-indicated vegetation extremes and their sensitivity to climate extremes

    International Nuclear Information System (INIS)

    Liu Guo; Liu Hongyan; Yin Yi

    2013-01-01

    Extremes in climate have significant impacts on ecosystems and are expected to increase under future climate change. Extremes in vegetation could capture such impacts and indicate the vulnerability of ecosystems, but currently have not received a global long-term assessment. In this study, a robust method has been developed to detect significant extremes (low values) in biweekly time series of global normalized difference vegetation index (NDVI) from 1982 to 2006 and thus to acquire a global pattern of vegetation extreme frequency. This pattern coincides with vegetation vulnerability patterns suggested by earlier studies using different methods over different time spans, indicating a consistent mechanism of regulation. Vegetation extremes were found to aggregate in Amazonia and in the semi-arid and semi-humid regions in low and middle latitudes, while they seldom occurred in high latitudes. Among the environmental variables studied, extreme low precipitation has the highest slope against extreme vegetation. For the eight biomes analyzed, these slopes are highest in temperate broadleaf forest and temperate grassland, suggesting a higher sensitivity in these environments. The results presented here contradict the hypothesis that vegetation in water-limited semi-arid and semi-humid regions might be adapted to drought and suggest that vegetation in these regions (especially temperate broadleaf forest and temperate grassland) is highly prone to vegetation extreme events under more severe precipitation extremes. It is also suggested here that more attention be paid to precipitation-induced vegetation changes than to temperature-induced events. (letter)

  8. Extreme weather events and infectious disease outbreaks.

    Science.gov (United States)

    McMichael, Anthony J

    2015-01-01

    Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and 'pestilence' associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations.

  9. Rapid adaptation of microalgae to bodies of water with extreme pollution from uranium mining: an explanation of how mesophilic organisms can rapidly colonise extremely toxic environments.

    Science.gov (United States)

    García-Balboa, C; Baselga-Cervera, B; García-Sanchez, A; Igual, J M; Lopez-Rodas, V; Costas, E

    2013-11-15

    Extreme environments may support communities of microalgae living at the limits of their tolerance. It is usually assumed that these extreme environments are inhabited by extremophile species. However, global anthropogenic environmental changes are generating new extreme environments, such as mining-effluent pools of residual waters from uranium mining with high U levels, acidity and radioactivity in Salamanca (Spain). Certain microalgal species have rapidly adapted to these extreme waters (uranium mining in this area began in 1960). Experiments have demonstrated that physiological acclimatisation would be unable to achieve adaptation. In contrast, rapid genetic adaptation was observed in waters ostensibly lethal to microalgae by means of rare spontaneous mutations that occurred prior to the exposure to effluent waters from uranium mining. However, adaptation to the most extreme conditions was only possible after recombination through sexual mating because adaptation requires more than one mutation. Microalgae living in extreme environments could be the descendants of pre-selective mutants that confer significant adaptive value to extreme contamination. These "lucky mutants" could allow for the evolutionary rescue of populations faced with rapid environmental change. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Microbial Fuel Cells under Extreme Salinity

    Science.gov (United States)

    Monzon del Olmo, Oihane

    I developed a Microbial Fuel Cell (MFC) that unprecedentedly works (i.e., produces electricity) under extreme salinity (≈ 100 g/L NaCl). Many industries, such as oil and gas extraction, generate hypersaline wastewaters with high organic strength, accounting for about 5% of worldwide generated effluents, which represent a major challenge for pollution control and resource recovery. This study assesses the potential for microbial fuel cells (MFCs) to treat such wastewaters and generate electricity under extreme saline conditions. Specifically, the focus is on the feasibility to treat hypersaline wastewater generated by the emerging unconventional oil and gas industry (hydraulic fracturing) and so, with mean salinity of 100 g/L NaCl (3-fold higher than sea water). The success of this novel technology strongly depends on finding a competent and resilient microbial community that can degrade the waste under extreme saline conditions and be able to use the anode as their terminal electron acceptor (exoelectrogenic capability). I demonstrated that MFCs can produce electricity at extremely high salinity (up to 250 g/l NaCl) with a power production of 71mW/m2. Pyrosequencing analysis of the anode population showed the predominance of Halanaerobium spp. (85%), which has been found in shale formations and oil reservoirs. Promoting Quorum sensing (QS, cell to cell communication between bacteria to control gene expression) was used as strategy to increase the attachment of bacteria to the anode and thus improve the MFC performance. Results show that the power output can be bolstered by adding 100nM of quinolone signal with an increase in power density of 30%, for the first time showing QS in Halanaerobium extremophiles. To make this technology closer to market applications, experiments with real wastewaters were also carried out. A sample of produced wastewater from Barnet Shale, Texas (86 g/L NaCl) produced electricity when fed in an MFC, leading to my discovery of another

  11. Characteristics of Extreme Extratropical Cyclones in a High-Resolution Global Climate Model

    Science.gov (United States)

    Catalano, A. J.; Broccoli, A. J.; Kapnick, S. B.; Janoski, T. P.

    2017-12-01

    In the northeastern United States, many of the strongest impacts from extratropical cyclones (ETCs) are associated with storms that exhibit slow movement, unusual tracks, or exceptional intensity. Examples of extreme ETCs include the Appalachian storm of November 1950, the Perfect Storm of October 1991, and the Superstorm of March 1993. Owing to the rare nature of these events, it is difficult to quantify the associated risks (e.g. high winds, storm surge) given the limited duration of high-quality observational datasets. Furthermore, storms with even greater impacts than those observed may be possible, particularly in a warming climate. In the context of tropical cyclones, Lin and Emanuel (2016) have used the metaphor "grey swans" to refer to high-impact events that have not been observed but may be physically possible. One method for analyzing "grey swans" is to generate a larger sample of ETCs using a coupled climate model. Therefore, we use long simulations (over 1,000 years with atmospheric constituents fixed at 1990 levels) from a global climate model (GFDL FLOR) with 50km atmospheric resolution. FLOR has been shown to realistically simulate the spatial distribution and climatology of ETCs during the reanalysis era. We will discuss the climatological features of these extreme ETC events.

  12. Expert consensus on facilitators and barriers to return-to-work following surgery for non-traumatic upper extremity conditions : A Delphi study

    NARCIS (Netherlands)

    Peters, S. E.; Johnston, V.; Ross, M.; Coppieters, M. W.

    2017-01-01

    This Delphi study aimed to reach consensus on important facilitators and barriers for return-to-work following surgery for non-traumatic upper extremity conditions. In Round 1, experts (n = 42) listed 134 factors, which were appraised in Rounds 2 and 3. Consensus (3/485% agreement) was achieved for

  13. Extending wind turbine operational conditions; a comparison of set point adaptation and LQG individual pitch control for highly turbulent wind

    International Nuclear Information System (INIS)

    Engels, W P; Subhani, S; Zafar, H; Savenije, F

    2014-01-01

    Extreme wind conditions can cause excessive loading on the turbine. This not only results in higher design loads, but when these conditions occur in practice, will also result in higher maintenance cost. Although there are already effective methods of dealing with gusts, other extreme conditions should also be examined. More specifically, extreme turbulence conditions (e.g. those specified by design load case 1.3 in IEC61400-1 ed. 3) require special attention as they can lead to design-driving extreme loads on blades, tower and other wind turbine components. This paper examines two methods to deal with extreme loads in a case of extreme turbulent wind. One method is derating the turbine, the other method is an individual pitch control (IPC) algorithm. Derating of the turbine can be achieved in two ways, one is changing the rated torque, the other is changing the rated rotor speed. The effect of these methods on fatigue loads and extreme loads is examined. Non-linear aero-elastic simulations using Phatas, show that reducing the rated rotor speed is far more effective at reducing the loads than reducing torque. Then, the IPC algorithm is proposed. This algorithm is a linear quadratic Gaussian (LQG) controller based on a time invariant model, defined in the fixed reference frame that includes the first tower and blade modes. Because this method takes the dynamics of the system into account more than conventional IPC control, it is expected that these loads dealt with more effectively, when they are particularly relevant. It is expected that in extreme turbulent the blade and tower dynamics are indeed more relevant. The effect of this algorithm on fatigue loads and pitch effort is examined and compared with the fatigue loads and pitch effort of reference IPC. Finally, the methods are compared in non-linear aero-elastic simulations with extreme turbulent wind

  14. Microbial ecology of extreme environments: Antarctic yeasts and growth in substrate-limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1985-01-01

    The high, dry valleys of the Ross Desert of Antarctic, characterized by extremely low temperatures, aridity and a depauperate biota, are used as an analog of the postulated extreme climates of other planetary bodies of the Solar System to test the hypothesis that if life could be supported by Ross, it might be possible where similar conditions prevail. The previously considered sterility of the Ross Desert soil ecosystem has yielded up an indigenous yeast, Cryptoccus vishniacci, which is able to resist the extremes of cold, wet and dry freezing, and long arid periods, while making minimal nutritional demands on the soil.

  15. A conditional extreme value theory approach in value-at-risk forecasting: Evidence from Southeastern Europe and USA market

    Directory of Open Access Journals (Sweden)

    Totić Selena

    2015-01-01

    Full Text Available As a consequence of the recent financial crisis, the adequacy of different Value-at-Risk (VaR methodologies was heavily questioned. Current practice in VaR assessment relies on modeling the whole distribution of returns. As an alternative, in this paper we model tail behavior of returns, and thus VaR, using conditional Extreme Value Theory (EVT, which combines EVT and GARCH methodology. Moreover, we examine the performance of conditional EVT with the daily returns of seven stock market indices, of which six are from Southeastern Europe (BelexLine, BET, BUX, CROBEX, SBITOP, SOFIX from the period of September 2004 - April 2013, and one from USA market (Standard&Poors 500 Index from the period January 1998 - April 2013. Backtesting of historical daily returns proves that conditional EVT model gives good predictions for all indices and for all confidence levels.

  16. Stable pelagic vertebrate community structure through extreme Paleogene greenhouse conditions

    Science.gov (United States)

    Sibert, E. C.; Friedman, M.; Hull, P. M.; Hunt, G.; Norris, R. D.

    2016-02-01

    The species composition (structure) and energy transfer (function) of an ecosystem is reflected by the presence and type of consumers that it supports. Here we use ichthyoliths, microfossil fish teeth and shark denticles, to assess the ecological variability of the pelagic fish community structure and composition from the Late Cretaceous to the middle Eocene from a drill core in the South Pacific gyre (DSDP Site 596). We find that the overall vertebrate community structure, as measured by the relative abundance of sharks to ray-finned fishes, has a punctuated change at the Cretaceous/Paleogene mass extinction. The vertebrate community structure remained stable throughout the Paleogene despite a five-fold increase in overall abundance of ichthyoliths during the extreme greenhouse of the Early Eocene. Further, we use a novel system to quantify the morphological variation in fish teeth. We find that the morphospace occupied by the tooth assemblage is conserved throughout the interval, with a slight expansion following the Cretaceous-Paleogene mass extinction, and the evolution of a distinct morphotype-group around the Paleocene-Eocene boundary. While there are elevated rates of morphotype origination and extinction following the Cretaceous-Paleogene mass extinction, the extreme greenhouse warming of the Early Eocene and associated increase in fish production produce near-zero origination and extinction rates. The relative stability in composition of the pelagic vertebrate community during intervals of extreme climate change and across large ranges of total fish accumulation, suggests that pelagic ecosystem structure is robust to climate events, and that the overall structure of the pelagic fish community may be decoupled from both climate and ecosystem function.

  17. TRISO-Coated Fuel Durability Under Extreme Conditions

    International Nuclear Information System (INIS)

    2014-01-01

    The PIs propose to examine TRISO-coated particles (SiC and ZrC coatings) in an integrated two-part study. In the first part, experiments will be performed to assess the reaction kinetics of the carbides under CO-CO2 environments at temperatures up to 1800 degree C. Kinetic model will be applied to describe the degradation. Scanning and transmission electron microscopy will be employed to establish the chemical and microstructure evolution under the imposed environmental conditions. The second part of the proposed work focuses on establishing the role of the high temperature, environmental exposure described above on the mechanical behavior of TRISO-coated particles. Electron microscopy and other advanced techniques will be subsequently performed to evaluate failure mechanisms. The work is expected to reveal relationships between corrosion reactions, starting material characteristics (polytype of SiC, impurity concentration, flaw distribution), flaw healing behavior, and crack growth.

  18. Neurodevelopmental problems and extremes in BMI

    Directory of Open Access Journals (Sweden)

    Nóra Kerekes

    2015-07-01

    Full Text Available Background. Over the last few decades, an increasing number of studies have suggested a connection between neurodevelopmental problems (NDPs and body mass index (BMI. Attention deficit/hyperactivity disorder (ADHD and autism spectrum disorders (ASD both seem to carry an increased risk for developing extreme BMI. However, the results are inconsistent, and there have been only a few studies of the general population of children.Aims. We had three aims with the present study: (1 to define the prevalence of extreme (low or high BMI in the group of children with ADHD and/or ASDs compared to the group of children without these NDPs; (2 to analyze whether extreme BMI is associated with the subdomains within the diagnostic categories of ADHD or ASD; and (3 to investigate the contribution of genetic and environmental factors to BMI in boys and girls at ages 9 and 12.Method. Parents of 9- or 12-year-old twins (n = 12,496 were interviewed using the Autism—Tics, ADHD and other Comorbidities (A-TAC inventory as part of the Child and Adolescent Twin Study in Sweden (CATSS. Univariate and multivariate generalized estimated equation models were used to analyze associations between extremes in BMI and NDPs.Results. ADHD screen-positive cases followed BMI distributions similar to those of children without ADHD or ASD. Significant association was found between ADHD and BMI only among 12-year-old girls, where the inattention subdomain of ADHD was significantly associated with the high extreme BMI. ASD scores were associated with both the low and the high extremes of BMI. Compared to children without ADHD or ASD, the prevalence of ASD screen-positive cases was three times greater in the high extreme BMI group and double as much in the low extreme BMI group. Stereotyped and repetitive behaviors were significantly associated with high extreme BMIs.Conclusion. Children with ASD, with or without coexisting ADHD, are more prone to have low or high extreme BMIs than

  19. Probabilistic analysis of extreme wind events

    Energy Technology Data Exchange (ETDEWEB)

    Chaviaropoulos, P.K. [Center for Renewable Energy Sources (CRES), Pikermi Attikis (Greece)

    1997-12-31

    A vital task in wind engineering and meterology is to understand, measure, analyse and forecast extreme wind conditions, due to their significant effects on human activities and installations like buildings, bridges or wind turbines. The latest version of the IEC standard (1996) pays particular attention to the extreme wind events that have to be taken into account when designing or certifying a wind generator. Actually, the extreme wind events within a 50 year period are those which determine the ``static`` design of most of the wind turbine components. The extremes which are important for the safety of wind generators are those associated with the so-called ``survival wind speed``, the extreme operating gusts and the extreme wind direction changes. A probabilistic approach for the analysis of these events is proposed in this paper. Emphasis is put on establishing the relation between extreme values and physically meaningful ``site calibration`` parameters, like probability distribution of the annual wind speed, turbulence intensity and power spectra properties. (Author)

  20. Thermal Implications for Extreme Fast Charge

    Energy Technology Data Exchange (ETDEWEB)

    Keyser, Matthew A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-08-14

    Present-day thermal management systems for battery electric vehicles are inadequate in limiting the maximum temperature rise of the battery during extreme fast charging. If the battery thermal management system is not designed correctly, the temperature of the cells could reach abuse temperatures and potentially send the cells into thermal runaway. Furthermore, the cell and battery interconnect design needs to be improved to meet the lifetime expectations of the consumer. Each of these aspects is explored and addressed as well as outlining where the heat is generated in a cell, the efficiencies of power and energy cells, and what type of battery thermal management solutions are available in today's market. Thermal management is not a limiting condition with regard to extreme fast charging, but many factors need to be addressed especially for future high specific energy density cells to meet U.S. Department of Energy cost and volume goals.

  1. Beryllium armoured target for extreme heat and neutron loading conditions

    International Nuclear Information System (INIS)

    Mazul, I.; Gervash, A.; Giniyatulin, R.

    2004-01-01

    Beryllium is a primary candidate as a target material for high-energy protons conversion into neutrons used for different applications. In order to get higher neutron flux the conversion area has to be minimized - in our case the target is limited by 1-2 liter volume. This target generates about 5·10 13 fast neutrons per second and removes of 150 kW thermal power deposited by proton beam (30 mA, 5 MeV), coming from linac. The operational condition of the converter is close to the condition of Be-armored components in fusion reactors: high thermal and neutron fluxes and active cooling. Therefore achievements in development of water-cooled high heat flux components for fusion application can be used for design of Be converter and vice versa. However for medical application the using of high-activated heat sink materials such as Cu and SS is strongly limited. So, new materials (Be, Al, Zr) and new joining technologies in comparison with the achievements in fusion area have to be used for construction of such Be converter. In order to reduce amount of heat sink materials in the target saddle-block geometry for Be armor is suggested and developed. Results of R and D works on the development of water cooled Be target for converter are presented, including data on selected materials, technological trials and mockups high heat flux testing. Preliminary design of Be neutron converter for medical applications based on R and D results is presented. (author)

  2. Recent and future warm extreme events and high-mountain slope stability.

    Science.gov (United States)

    Huggel, C; Salzmann, N; Allen, S; Caplan-Auerbach, J; Fischer, L; Haeberli, W; Larsen, C; Schneider, D; Wessels, R

    2010-05-28

    The number of large slope failures in some high-mountain regions such as the European Alps has increased during the past two to three decades. There is concern that recent climate change is driving this increase in slope failures, thus possibly further exacerbating the hazard in the future. Although the effects of a gradual temperature rise on glaciers and permafrost have been extensively studied, the impacts of short-term, unusually warm temperature increases on slope stability in high mountains remain largely unexplored. We describe several large slope failures in rock and ice in recent years in Alaska, New Zealand and the European Alps, and analyse weather patterns in the days and weeks before the failures. Although we did not find one general temperature pattern, all the failures were preceded by unusually warm periods; some happened immediately after temperatures suddenly dropped to freezing. We assessed the frequency of warm extremes in the future by analysing eight regional climate models from the recently completed European Union programme ENSEMBLES for the central Swiss Alps. The models show an increase in the higher frequency of high-temperature events for the period 2001-2050 compared with a 1951-2000 reference period. Warm events lasting 5, 10 and 30 days are projected to increase by about 1.5-4 times by 2050 and in some models by up to 10 times. Warm extremes can trigger large landslides in temperature-sensitive high mountains by enhancing the production of water by melt of snow and ice, and by rapid thaw. Although these processes reduce slope strength, they must be considered within the local geological, glaciological and topographic context of a slope.

  3. Extreme Spectroscopy: In situ nuclear materials behavior from optical data

    Energy Technology Data Exchange (ETDEWEB)

    Guimbretiere, G.; Canizares, A.; Raimboux, N.; Omnee, R.; Duval, F.; Ammar, M.R.; Simon, P. [CNRS - UPR3079 CEMHTI, Universite d' Orleans, 45071Orleans cedex 2 (France); Desgranges, L.; Mohun, R. [CEA, DEN, DEC, F-13108 Saint-Paul-Lez-Durance (France); Jegou, C.; Magnin, M. [CEA/DTCD/SECM/LMPA, Marcoule 30207 Bagnols Sur Ceze (France); Clavier, N.; Dacheux, N. [ICSM-UMR5257 CEA/CNRS/UM2/ENSCM, Marcoule, BP17171, 30207 Bagnols sur Ceze (France)

    2015-07-01

    In the nuclear industry, materials are regularly exposed to high temperature or/and irradiation and a better knowledge and understanding of their behavior under such extreme conditions is a key-point for improvements and further developments. Nowadays, Raman spectroscopy begins to be well known as a promising technique in the post mortem and remote characterization of nuclear materials exposed to extreme conditions. On this topic, at ANIMMA 2013 conference, we have presented some results about its implementation in the study of model or real nuclear fuel. However, the strength of Raman spectroscopy as in situ characterization tool is mainly its ability to be implemented remotely through optical fibers. Aware of this, implementation of other optical techniques can be considered in order to gain information not only on the structural dynamics of materials but also on the electronic charge carrier populations. In this paper, we propose to present our last advances in Raman characterization of nuclear materials and enlarge to the in situ use of complementary optical spectroscopies. Emphasis will be made on the information that can be gained to the behavior of the model fuel depleted UO{sub 2} under extreme conditions of high temperature and ionic irradiation: - In Situ Raman identification of the radiolysis alteration products of UO{sub 2} in contact with water under ionic irradiation. - In Situ Raman recording of the damaged dynamic of UO{sub 2} under inert atmosphere. - In Situ Raman and photo-luminescence study of virgin and damaged UO2 at high temperature. - In Situ study of electronic charge carriers' behavior in U{sub x}Th{sub 1-x}O{sub 2} solid solutions by mean of Iono- and Thermo- luminescence under and post- ionic irradiation. (authors)

  4. INLA goes extreme: Bayesian tail regression for the estimation of high spatio-temporal quantiles

    KAUST Repository

    Opitz, Thomas; Huser, Raphaë l; Bakka, Haakon; Rue, Haavard

    2018-01-01

    approach is based on a Bayesian generalized additive modeling framework that is designed to estimate complex trends in marginal extremes over space and time. First, we estimate a high non-stationary threshold using a gamma distribution for precipitation

  5. Extreme Environment Circuit Blocks for Spacecraft Power & Propulsion System & Other High Reliability Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Chronos Technology (DIv of FMI, Inc.) proposes to design, fabricate, and deliver a performance proven, and commercially available set of extreme high operating...

  6. Atmospheric and Fog Effects on Ultra-Wide Band Radar Operating at Extremely High Frequencies.

    Science.gov (United States)

    Balal, Nezah; Pinhasi, Gad A; Pinhasi, Yosef

    2016-05-23

    The wide band at extremely high frequencies (EHF) above 30 GHz is applicable for high resolution directive radars, resolving the lack of free frequency bands within the lower part of the electromagnetic spectrum. Utilization of ultra-wideband signals in this EHF band is of interest, since it covers a relatively large spectrum, which is free of users, resulting in better resolution in both the longitudinal and transverse dimensions. Noting that frequencies in the millimeter band are subjected to high atmospheric attenuation and dispersion effects, a study of the degradation in the accuracy and resolution is presented. The fact that solid-state millimeter and sub-millimeter radiation sources are producing low power, the method of continuous-wave wideband frequency modulation becomes the natural technique for remote sensing and detection. Millimeter wave radars are used as complementary sensors for the detection of small radar cross-section objects under bad weather conditions, when small objects cannot be seen by optical cameras and infrared detectors. Theoretical analysis for the propagation of a wide "chirped" Frequency-Modulated Continuous-Wave (FMCW) radar signal in a dielectric medium is presented. It is shown that the frequency-dependent (complex) refractivity of the atmospheric medium causes distortions in the phase of the reflected signal, introducing noticeable errors in the longitudinal distance estimations, and at some frequencies may also degrade the resolution.

  7. Do climate extreme events foster violent civil conflicts? A coincidence analysis

    Science.gov (United States)

    Schleussner, Carl-Friedrich; Donges, Jonathan F.; Donner, Reik V.

    2014-05-01

    Civil conflicts promoted by adverse environmental conditions represent one of the most important potential feedbacks in the global socio-environmental nexus. While the role of climate extremes as a triggering factor is often discussed, no consensus is yet reached about the cause-and-effect relation in the observed data record. Here we present results of a rigorous statistical coincidence analysis based on the Munich Re Inc. extreme events database and the Uppsala conflict data program. We report evidence for statistically significant synchronicity between climate extremes with high economic impact and violent conflicts for various regions, although no coherent global signal emerges from our analysis. Our results indicate the importance of regional vulnerability and might aid to identify hot-spot regions for potential climate-triggered violent social conflicts.

  8. A COMPARISON OF UPPER-EXTREMITY REACTION FORCES BETWEEN THE YURCHENKO VAULT AND FLOOR EXERCISE

    Directory of Open Access Journals (Sweden)

    Matthew Kirk Seeley

    2005-06-01

    Full Text Available The purpose of this study was to examine reaction forces transmitted to the upper extremities of high-level gymnasts during the round-off phase of the Yurchenko vault. A secondary purpose of this study was to compare reaction forces during the Yurchenko vault to reaction forces observed in a tumbling pass during the floor exercise. Ten high-level, female gymnasts volunteered to participate. Conditions of the independent variable were the Yurchenko vault and floor exercise; dependent variables were peak vertical and peak anterior-posterior reaction forces. Each participant performed three trials of both conditions with the trail hand contacting a force platform. Vertical and anterior-posterior reaction forces, normalized to body weight, were greater (p < 0.05 during the round-off phase of the Yurchenko vault (2.38 than during the floor exercise round-off (2.15. Vertical reaction forces during the round-off phase of the Yurchenko vault and floor exercise round-off are similar to reaction forces transmitted to upper extremities during other gymnastic skills and ground reaction forces transmitted to lower extremities while running and walking at various speeds. Results of this study reveal a need for further research considering methods aimed at reducing reaction forces transmitted to the upper extremities during the Yurchenko vault and floor exercise.

  9. Improving real-time estimation of heavy-to-extreme precipitation using rain gauge data via conditional bias-penalized optimal estimation

    Science.gov (United States)

    Seo, Dong-Jun; Siddique, Ridwan; Zhang, Yu; Kim, Dongsoo

    2014-11-01

    A new technique for gauge-only precipitation analysis for improved estimation of heavy-to-extreme precipitation is described and evaluated. The technique is based on a novel extension of classical optimal linear estimation theory in which, in addition to error variance, Type-II conditional bias (CB) is explicitly minimized. When cast in the form of well-known kriging, the methodology yields a new kriging estimator, referred to as CB-penalized kriging (CBPK). CBPK, however, tends to yield negative estimates in areas of no or light precipitation. To address this, an extension of CBPK, referred to herein as extended conditional bias penalized kriging (ECBPK), has been developed which combines the CBPK estimate with a trivial estimate of zero precipitation. To evaluate ECBPK, we carried out real-world and synthetic experiments in which ECBPK and the gauge-only precipitation analysis procedure used in the NWS's Multisensor Precipitation Estimator (MPE) were compared for estimation of point precipitation and mean areal precipitation (MAP), respectively. The results indicate that ECBPK improves hourly gauge-only estimation of heavy-to-extreme precipitation significantly. The improvement is particularly large for estimation of MAP for a range of combinations of basin size and rain gauge network density. This paper describes the technique, summarizes the results and shares ideas for future research.

  10. Satellite-Enhanced Dynamical Downscaling of Extreme Events

    Science.gov (United States)

    Nunes, A.

    2015-12-01

    Severe weather events can be the triggers of environmental disasters in regions particularly susceptible to changes in hydrometeorological conditions. In that regard, the reconstruction of past extreme weather events can help in the assessment of vulnerability and risk mitigation actions. Using novel modeling approaches, dynamical downscaling of long-term integrations from global circulation models can be useful for risk analysis, providing more accurate climate information at regional scales. Originally developed at the National Centers for Environmental Prediction (NCEP), the Regional Spectral Model (RSM) is being used in the dynamical downscaling of global reanalysis, within the South American Hydroclimate Reconstruction Project. Here, RSM combines scale-selective bias correction with assimilation of satellite-based precipitation estimates to downscale extreme weather occurrences. Scale-selective bias correction is a method employed in the downscaling, similar to the spectral nudging technique, in which the downscaled solution develops in agreement with its coarse boundaries. Precipitation assimilation acts on modeled deep-convection, drives the land-surface variables, and therefore the hydrological cycle. During the downscaling of extreme events that took place in Brazil in recent years, RSM continuously assimilated NCEP Climate Prediction Center morphing technique precipitation rates. As a result, RSM performed better than its global (reanalysis) forcing, showing more consistent hydrometeorological fields compared with more sophisticated global reanalyses. Ultimately, RSM analyses might provide better-quality initial conditions for high-resolution numerical predictions in metropolitan areas, leading to more reliable short-term forecasting of severe local storms.

  11. Observations and predictions of wave runup, extreme water levels, and medium-term dune erosion during storm conditions

    OpenAIRE

    Suanez , Serge ,; Cancouët , Romain; Floc'h , France; Blaise , Emmanuel; Ardhuin , Fabrice; Filipot , Jean-François; Cariolet , Jean-Marie; Delacourt , Christophe

    2015-01-01

    Monitoring of dune erosion and accretion on the high-energy macrotidal Vougot beach in North Brittany (France) over the past decade (2004–2014) has revealed significant morphological changes. Dune toe erosion/accretion records have been compared with extreme water level measurements, defined as the sum of (i) astronomic tide; (ii) storm surge; and (iii) vertical wave runup. Runup parameterization was conducted using swash limits, beach profiles, and hydrodynamic (Hm0, Tm0,–1, and high tide wa...

  12. Optimization with Extremal Dynamics

    International Nuclear Information System (INIS)

    Boettcher, Stefan; Percus, Allon G.

    2001-01-01

    We explore a new general-purpose heuristic for finding high-quality solutions to hard discrete optimization problems. The method, called extremal optimization, is inspired by self-organized criticality, a concept introduced to describe emergent complexity in physical systems. Extremal optimization successively updates extremely undesirable variables of a single suboptimal solution, assigning them new, random values. Large fluctuations ensue, efficiently exploring many local optima. We use extremal optimization to elucidate the phase transition in the 3-coloring problem, and we provide independent confirmation of previously reported extrapolations for the ground-state energy of ±J spin glasses in d=3 and 4

  13. Disaster Risks Reduction for Extreme Natural Hazards

    Science.gov (United States)

    Plag, H.; Jules-Plag, S.

    2013-12-01

    Mega disasters associated with extreme natural hazards have the potential to escalate the global sustainability crisis and put us close to the boundaries of the safe operating space for humanity. Floods and droughts are major threats that potentially could reach planetary extent, particularly through secondary economic and social impacts. Earthquakes and tsunamis frequently cause disasters that eventually could exceed the immediate coping capacity of the global economy, particularly since we have built mega cities in hazardous areas that are now ready to be harvested by natural hazards. Unfortunately, the more we learn to cope with the relatively frequent hazards (50 to 100 years events), the less we are worried about the low-probability, high-impact events (a few hundred and more years events). As a consequence, threats from the 500 years flood, drought, volcano eruption are not appropriately accounted for in disaster risk reduction (DRR) discussions. Extreme geohazards have occurred regularly throughout the past, but mostly did not cause major disasters because exposure of human assets to hazards was much lower in the past. The most extreme events that occurred during the last 2,000 years would today cause unparalleled damage on a global scale and could worsen the sustainability crisis. Simulation of these extreme hazards under present conditions can help to assess the disaster risk. Recent extreme earthquakes have illustrated the destruction they can inflict, both directly and indirectly through tsunamis. Large volcano eruptions have the potential to impact climate, anthropogenic infrastructure and resource supplies on global scale. During the last 2,000 years several large volcano eruptions occurred, which under today's conditions are associated with extreme disaster risk. The comparison of earthquakes and volcano eruptions indicates that large volcano eruptions are the low-probability geohazards with potentially the highest impact on our civilization

  14. EXTREME WINTERS IN XX–XXI CENTURIES AS INDICATORS OF SNOWINESS AND AVALANCHE HAZARD IN THE PAST AND EXPECTED CLIMATE CHANGE CONDITIONS

    Directory of Open Access Journals (Sweden)

    A. D. Oleynikov

    2012-01-01

    Full Text Available Currently, due to the global climate change and increasing frequency of weather events focus is on prediction of climate extremes. Large-scale meteorological anomalies can cause long-term paralysis of social and economic infrastructure of the major mountain regions and even individual states. In winter periods, these anomalies are associated with prolonged heavy snowfalls and associated with them catastrophic avalanches which cause significant social and economic damage. The climate system maintains a certain momentum during periods of adjustment and transition to other conditions in the ratio of heat and moisture and contains a climate «signal» of the climates of the past and the future. In our view seasonal and yearly extremes perform the role of these indicators, study of which enables for a deeper understanding and appreciation of the real situation of the climate periods related to the modern ones. The paper provides an overview of the criteria for selection of extreme winters. Identification of extremely cold winters during the period of instrumental observation and assessment of their snowiness and avalanche activity done for the Elbrus region, which is a model site for study of the avalanche regime in the Central Caucasus. The studies aim to identify the extreme winters in the Greater Caucasus, assess their frequency of occurrence, characterize the scale and intensity of the avalanche formation. The data obtained can be used to identify winter-analogues in the reconstruction and long-term forecast of avalanches. 

  15. The Effect of Sport Specialization on Lower Extremity Injury Rates in High School Athletes

    OpenAIRE

    McGuine, Timothy A.; Bell, David; Brooks, Margaret Alison; Hetzel, Scott; Pfaller, Adam; Post, Eric

    2017-01-01

    Objectives: Sport specialization has been shown to be associated with increased risk of musculoskeletal lower extremity injuries (LEI) in adolescent athletes presenting in clinical settings. However, the association of sport specialization and incidence of LEI has not been studied prospectively in a large population of adolescent athletes. The objective of this study was to compare the incidence of LEI in high school athletes identified as having low (LOW), moderate (MOD) or high (HIGH) level...

  16. Liquid jet impingement cooling with diamond substrates for extremely high heat flux applications

    International Nuclear Information System (INIS)

    Lienhard V, J.H.

    1993-01-01

    The combination of impinging jets and diamond substrates may provide an effective solution to a class of extremely high heat flux problems in which very localized heat loads must be removed. Some potential applications include the cooling of high-heat-load components in synchrotron x-ray, fusion, and semiconductor laser systems. Impinging liquid jets are a very effective vehicle for removing high heat fluxes. The liquid supply arrangement is relatively simple, and low thermal resistances can be routinely achieved. A jet's cooling ability is a strong function of the size of the cooled area relative to the jet diameter. For relatively large area targets, the critical heat fluxes can approach 20 W/mm 2 . In this situation, burnout usually originates at the outer edge of the cooled region as increasing heat flux inhibits the liquid supply. Limitations from liquid supply are minimized when heating is restricted to the jet stagnation zone. The high stagnation pressure and high velocity gradients appear to suppress critical flux phenomena, and fluxes of up to 400 W/mm 2 have been reached without evidence of burnout. Instead, the restrictions on heat flux are closely related to properties of the cooled target. Target properties become an issue owing to the large temperatures and large temperature gradients that accompany heat fluxes over 100 W/mm 2 . These conditions necessitate a target with both high thermal conductivity to prevent excessive temperatures and good mechanical properties to prevent mechanical failures. Recent developments in synthetic diamond technology present a possible solution to some of the solid-side constraints on heat flux. Polycrystalline diamond foils can now be produced by chemical vapor deposition in reasonable quantity and at reasonable cost. Synthetic single crystal diamonds as large as 1 cm 2 are also available

  17. Intensity changes in future extreme precipitation: A statistical event-based approach.

    Science.gov (United States)

    Manola, Iris; van den Hurk, Bart; de Moel, Hans; Aerts, Jeroen

    2017-04-01

    Short-lived precipitation extremes are often responsible for hazards in urban and rural environments with economic and environmental consequences. The precipitation intensity is expected to increase about 7% per degree of warming, according to the Clausius-Clapeyron (CC) relation. However, the observations often show a much stronger increase in the sub-daily values. In particular, the behavior of the hourly summer precipitation from radar observations with the dew point temperature (the Pi-Td relation) for the Netherlands suggests that for moderate to warm days the intensification of the precipitation can be even higher than 21% per degree of warming, that is 3 times higher than the expected CC relation. The rate of change depends on the initial precipitation intensity, as low percentiles increase with a rate below CC, the medium percentiles with 2CC and the moderate-high and high percentiles with 3CC. This non-linear statistical Pi-Td relation is suggested to be used as a delta-transformation to project how a historic extreme precipitation event would intensify under future, warmer conditions. Here, the Pi-Td relation is applied over a selected historic extreme precipitation event to 'up-scale' its intensity to warmer conditions. Additionally, the selected historic event is simulated in the high-resolution, convective-permitting weather model Harmonie. The initial and boundary conditions are alternated to represent future conditions. The comparison between the statistical and the numerical method of projecting the historic event to future conditions showed comparable intensity changes, which depending on the initial percentile intensity, range from below CC to a 3CC rate of change per degree of warming. The model tends to overestimate the future intensities for the low- and the very high percentiles and the clouds are somewhat displaced, due to small wind and convection changes. The total spatial cloud coverage in the model remains, as also in the statistical

  18. Communication: A novel method for generating molecular mixtures at extreme conditions: The case of hydrogen and oxygen

    International Nuclear Information System (INIS)

    Pravica, Michael; Sneed, Daniel; White, Melanie; Wang, Yonggang

    2014-01-01

    We have successfully created a segregated mixture of hydrogen and oxygen at high pressure in a diamond anvil cell using hard x-ray photochemistry. A keyhole (two holes connected by an opening) sample chamber was created in a metallic gasket to support two segregated powders of ammonia borane and potassium perchlorate, respectively, in each hole at a pressure of ∼5.0 GPa. Both holes were separately irradiated with synchrotron hard x-rays to release molecular oxygen and molecular hydrogen, respectively. Upon irradiation of the first KClO 4 -containing hole, solid reddish-orange O 2 appeared in the region of irradiation and molecular oxygen was found to diffuse throughout the entire sample region. The second ammonia borane-containing hole was then irradiated and H 2 was observed to form via Raman spectroscopy. Water also was observed in the ammonia borane-containing hole and possibly (in the form of ice VII) in the second hole. This unique experiment demonstrates the ability to easily create solid mixtures of simple molecular systems via x-ray irradiation and then react them via further irradiation which will aid the study of chemistry under extreme conditions

  19. Extreme fire severity patterns in topographic, convective and wind-driven historical wildfires of Mediterranean pine forests.

    Directory of Open Access Journals (Sweden)

    Judit Lecina-Diaz

    Full Text Available Crown fires associated with extreme fire severity are extremely difficult to control. We have assessed fire severity using differenced Normalized Burn Ratio (dNBR from Landsat imagery in 15 historical wildfires of Pinus halepensis Mill. We have considered a wide range of innovative topographic, fuel and fire behavior variables with the purposes of (1 determining the variables that influence fire severity patterns among fires (considering the 15 wildfires together and (2 ascertaining whether different variables affect extreme fire severity within the three fire types (topographic, convective and wind-driven fires. The among-fires analysis showed that fires in less arid climates and with steeper slopes had more extreme severity. In less arid conditions there was more crown fuel accumulation and closer forest structures, promoting high vertical and horizontal fuel continuity and extreme fire severity. The analyses carried out for each fire separately (within fires showed more extreme fire severity in areas in northern aspects, with steeper slopes, with high crown biomass and in climates with more water availability. In northern aspects solar radiation was lower and fuels had less water limitation to growth which, combined with steeper slopes, produced more extreme severity. In topographic fires there was more extreme severity in northern aspects with steeper slopes and in areas with more water availability and high crown biomass; in convection-dominated fires there was also more extreme fire severity in northern aspects with high biomass; while in wind-driven fires there was only a slight interaction between biomass and water availability. This latter pattern could be related to the fact that wind-driven fires spread with high wind speed, which could have minimized the effect of other variables. In the future, and as a consequence of climate change, new zones with high crown biomass accumulated in non-common drought areas will be available to burn

  20. Extreme fire severity patterns in topographic, convective and wind-driven historical wildfires of Mediterranean pine forests.

    Science.gov (United States)

    Lecina-Diaz, Judit; Alvarez, Albert; Retana, Javier

    2014-01-01

    Crown fires associated with extreme fire severity are extremely difficult to control. We have assessed fire severity using differenced Normalized Burn Ratio (dNBR) from Landsat imagery in 15 historical wildfires of Pinus halepensis Mill. We have considered a wide range of innovative topographic, fuel and fire behavior variables with the purposes of (1) determining the variables that influence fire severity patterns among fires (considering the 15 wildfires together) and (2) ascertaining whether different variables affect extreme fire severity within the three fire types (topographic, convective and wind-driven fires). The among-fires analysis showed that fires in less arid climates and with steeper slopes had more extreme severity. In less arid conditions there was more crown fuel accumulation and closer forest structures, promoting high vertical and horizontal fuel continuity and extreme fire severity. The analyses carried out for each fire separately (within fires) showed more extreme fire severity in areas in northern aspects, with steeper slopes, with high crown biomass and in climates with more water availability. In northern aspects solar radiation was lower and fuels had less water limitation to growth which, combined with steeper slopes, produced more extreme severity. In topographic fires there was more extreme severity in northern aspects with steeper slopes and in areas with more water availability and high crown biomass; in convection-dominated fires there was also more extreme fire severity in northern aspects with high biomass; while in wind-driven fires there was only a slight interaction between biomass and water availability. This latter pattern could be related to the fact that wind-driven fires spread with high wind speed, which could have minimized the effect of other variables. In the future, and as a consequence of climate change, new zones with high crown biomass accumulated in non-common drought areas will be available to burn as extreme

  1. [The heart in extreme sports: hyperbaric activity and microgravity].

    Science.gov (United States)

    Berrettini, Umberto; Landolfi, Angelo; Patteri, Giovanna

    2008-10-01

    The study of the cardiovascular and respiratory modifications in extreme environments could be useful for the understanding of the adaptive mechanisms of the body in particular conditions. The knowledge of how different environmental conditions in terms of extreme pressure, temperature and gravity modify the neurovegetative and cardiovascular system could be useful in daily practice for hypobaric and hyperbaric sports.

  2. Assessing Climate Variability using Extreme Rainfall and ...

    African Journals Online (AJOL)

    user1

    extreme frequency); the average intensity of rainfall from extreme events ... frequency and extreme intensity indices, suggesting that extreme events are more frequent and intense during years with high rainfall. The proportion of total rainfall from ...

  3. Thermal science under extreme conditions. Proceedings of the annual congress of the French Society of Thermal science - SFT 2012, 29 May-1 June, Bordeaux-Talence

    International Nuclear Information System (INIS)

    Gendrhi, Philippe; Perrin, Bernard; Journeau, Christophe; MOST, Jean-Michel; Nicolai, Philippe

    2012-06-01

    This publication proposes the contributions made during plenary sessions, and those made on various themes (Multi-physical couplings combustion; Contacts and interfaces; Natural, hybrid and forced convection, Energy and the environment; High temperatures and high flows; Metrology and identification; Micro- and nano-thermal science; Radiation; Control of systems and thermal process; System thermal science; Life thermal science; Transfer in multi-phase media; Transfer in porous media). Among the plenary session conferences some authors more particularly addressed the following issues: Thermal science at the heart of thermonuclear fusion (presentation of thermonuclear fusion by magnetic confinement); Thermal science of severe accidents of nuclear reactors (study of the thermal science of corium-water interaction which could result in a thermal detonation, study of corium baths at the vessel bottom or in interaction with the vessel well concrete, proposition of technological solutions for corium recovery); Fusion by inertial confinement and associated energy exchanges (case of inertial confinement by power lasers, presentation of needed conditions to obtain an energetic gain, of different energy and heat transfers under extreme conditions)

  4. Extremely deformable structures

    CERN Document Server

    2015-01-01

    Recently, a new research stimulus has derived from the observation that soft structures, such as biological systems, but also rubber and gel, may work in a post critical regime, where elastic elements are subject to extreme deformations, though still exhibiting excellent mechanical performances. This is the realm of ‘extreme mechanics’, to which this book is addressed. The possibility of exploiting highly deformable structures opens new and unexpected technological possibilities. In particular, the challenge is the design of deformable and bi-stable mechanisms which can reach superior mechanical performances and can have a strong impact on several high-tech applications, including stretchable electronics, nanotube serpentines, deployable structures for aerospace engineering, cable deployment in the ocean, but also sensors and flexible actuators and vibration absorbers. Readers are introduced to a variety of interrelated topics involving the mechanics of extremely deformable structures, with emphasis on ...

  5. Effects of elevated mean and extremely high temperatures on the physio-ecological characteristics of geographically distinctive populations of Cunninghamia lanceolata

    Science.gov (United States)

    Zhou, Ting; Jia, Xiaorong; Liao, Huixuan; Peng, Shijia; Peng, Shaolin

    2016-12-01

    Conventional models for predicting species distribution under global warming scenarios often treat one species as a homogeneous whole. In the present study, we selected Cunninghamia lanceolata (C. lanceolata), a widely distributed species in China, to investigate the physio-ecological responses of five populations under different temperature regimes. The results demonstrate that increased mean temperatures induce increased growth performance among northern populations, which exhibited the greatest germination capacity and largest increase in the overlap between the growth curve and the monthly average temperature. However,tolerance of the southern population to extremely high temperatures was stronger than among the population from the northern region,shown by the best growth and the most stable photosynthetic system of the southern population under extremely high temperature. This result indicates that the growth advantage among northern populations due to increased mean temperatures may be weakened by lower tolerance to extremely high temperatures. This finding is antithetical to the predicted results. The theoretical coupling model constructed here illustrates that the difference in growth between populations at high and low latitudes and altitudes under global warming will decrease because of the frequent occurrence of extremely high temperatures.

  6. Performance of High Temperature Operational Amplifier, Type LM2904WH, under Extreme Temperatures

    Science.gov (United States)

    Patterson, Richard; Hammoud, Ahmad; Elbuluk, Malik

    2008-01-01

    Operation of electronic parts and circuits under extreme temperatures is anticipated in NASA space exploration missions as well as terrestrial applications. Exposure of electronics to extreme temperatures and wide-range thermal swings greatly affects their performance via induced changes in the semiconductor material properties, packaging and interconnects, or due to incompatibility issues between interfaces that result from thermal expansion/contraction mismatch. Electronics that are designed to withstand operation and perform efficiently in extreme temperatures would mitigate risks for failure due to thermal stresses and, therefore, improve system reliability. In addition, they contribute to reducing system size and weight, simplifying its design, and reducing development cost through the elimination of otherwise required thermal control elements for proper ambient operation. A large DC voltage gain (100 dB) operational amplifier with a maximum junction temperature of 150 C was recently introduced by STMicroelectronics [1]. This LM2904WH chip comes in a plastic package and is designed specifically for automotive and industrial control systems. It operates from a single power supply over a wide range of voltages, and it consists of two independent, high gain, internally frequency compensated operational amplifiers. Table I shows some of the device manufacturer s specifications.

  7. Crystallization and Thermoelectric Transport in Semiconductor Micro- and Nanostructures Under Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gokirmak, Ali [Univ. of Connecticut, Storrs, CT (United States); Silva, Helena [Univ. of Connecticut, Storrs, CT (United States)

    2017-08-30

    This project focused on thermoelectric transport in semiconductor micro and nanostructures where moderate and typical operating voltages and currents lead to extreme thermal gradients and current densities. Models that describe behavior of semiconducting materials typically assume an equilibrium condition or slight deviations from it. In these cases the generation-recombination processes are assumed to have reached a local equilibrium for a given temperature. Hence, free carrier concentrations and their mobilities, band-gap, thermal conductivity, thermoelectric properties, mobility of atoms and mechanical properties of the material, can be described as a function of temperature. In the case of PN junctions under electrical bias, carrier concentrations can change up to ~ 1020 cm-3 and a drift-diffusion approximation is typically used to obtain the carrier concentrations while assuming that the material properties do not change. In non-equilibrium conditions, the assumption that the material properties remain the same may not be valid. While the increased conduction-band electron concentration may not have a drastic effect on the material, large hole concentration is expected to soften the material as ‘a hole’ comes into existence as a broken bond in the lattice. As the hole density approaches 1022 cm-3, the number of bonds holding the lattice together is significantly reduced, making it easier to break additional bonds, reduce band-gap and inhibit phonon transport. As these holes move away from where they were generated, local properties are expected to deviate significantly from the equilibrium case. Hence, temperature alone is not sufficient to describe the behavior of the material. The behavior of the solid material close to a molten region (liquid-solid interfaces) is also expected to deviate from the equilibrium case as a function of hole injection rate, which can be drastically increased or decreased in the presence of an electric field. In the past years

  8. Extreme Environment High Temperature Communication Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop and demonstrate a communications system capable of operation at extreme temperatures and pressures in hostile and corrosive...

  9. Identification of extreme motor phenotypes in Huntington's disease.

    Science.gov (United States)

    Braisch, Ulrike; Hay, Birgit; Muche, Rainer; Rothenbacher, Dietrich; Landwehrmeyer, G Bernhard; Long, Jeffrey D; Orth, Michael

    2017-04-01

    The manifestation of motor signs in Huntington's disease (HD) has a well-known inverse relationship with HTT CAG repeat length, but the prediction is far from perfect. The probability of finding disease modifiers is enhanced in individuals with extreme HD phenotypes. We aimed to identify extreme HD motor phenotypes conditional on CAG and age, such as patients with very early or very late onset of motor manifestation. Retrospective data were available from 1,218 healthy controls and 9,743 HD participants with CAG repeats ≥40, and a total of about 30,000 visits. Boundaries (2.5% and 97.5% quantiles) for extreme motor phenotypes (UHDRS total motor score (TMS) and motor age-at-onset) were estimated using quantile regression for longitudinal data. More than 15% of HD participants had an extreme TMS phenotype for at least one visit. In contrast, only about 4% of participants were consistent TMS extremes at two or more visits. Data from healthy controls revealed an upper cut-off of 13 for the TMS representing the extreme of motor ratings for a normal aging population. In HD, boundaries of motor age-at-onset based on diagnostic confidence or derived from the TMS data cut-off in controls were similar. In summary, a UHDRS TMS of more than 13 in an individual carrying the HD mutation indicates a high likelihood of motor manifestations of HD irrespective of CAG repeat length or age. The identification of motor phenotype extremes can be useful in the search for disease modifiers, for example, genetic or environmental such as medication. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Decrease in hydroclimatic conditions generating floods in the southeast of Belgium over the last 50 years resulting from changes in seasonal snow cover and extreme precipitation events

    Science.gov (United States)

    Wyard, Coraline; Fettweis, Xavier

    2016-04-01

    As a consequence of climate change, several studies concluded that winter flood occurrence could increase in the future in many rivers of northern and western Europe in response to an increase in extreme precipitation events. This study aims to determine if trends in extreme hydroclimatic events generating floods can already be detected over the last century. In particular, we focus on the Ourthe River (southeast of Belgium) which is one of the main tributaries of the Meuse River with a catchment area of 3500 km². In this river, most of the floods occur during winter and about 50% of them are due to rainfall events associated with the melting of the snow which covers the Ardennes during winter. In this study, hydroclimatic conditions favorable to flooding were reconstructed over the 20th century using the regional climate model MAR ("Modèle Atmosphérique Régional") forced by the following reanalyses: the ERA-20C, the ERA-Interim and the NCEP/NCAR-v1. The use of the MAR model allows to compute precipitation, snow depth and run-off resulting from precipitation events and snow melting in any part of the Ourthe river catchment area. Therefore, extreme hydroclimatic events, namely extreme run-off events, which could potentially generate floods, can be reconstructed using the MAR model. As validation, the MAR results were compared to weather station-based data. A trend analysis was then performed in order to study the evolution of conditions favorable to flooding in the Ourthe River catchment. The results show that the MAR model allows the detection of more than 95% of the hydroclimatic conditions which effectively generated observed floods in the Ourthe River over the 1974-2014 period. Conditions favorable to flooding present a negative trend over the last 50 years as a result of a decrease in snow accumulation and in extreme precipitation events. However, significance of these trends depends on the reanalysis used to force the regional climate model as well as the

  11. An influence of extremal edges on boundary extension.

    Science.gov (United States)

    Hale, Ralph G; Brown, James M; McDunn, Benjamin A; Siddiqui, Aisha P

    2015-08-01

    Studies have shown that people consistently remember seeing more of a studied scene than was physically present (e.g., Intraub & Richardson Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 179-187, 1989). This scene memory error, known as boundary extension, has been suggested to occur due to an observer's failure to differentiate between the contributing sources of information, including the sensory input, amodal continuation beyond the view boundaries, and contextual associations with the main objects and depicted scene locations (Intraub, 2010). Here, "scenes" made of abstract shapes on random-dot backgrounds, previously shown to elicit boundary extension (McDunn, Siddiqui, & Brown Psychonomic Bulletin & Review, 21, 370-375, 2014), were compared with versions made with extremal edges (Palmer & Ghose Psychological Science, 19, 77-84, 2008) added to their borders, in order to examine how boundary extension is influenced when amodal continuation at the borders' view boundaries is manipulated in this way. Extremal edges were expected to reduce boundary extension as compared to the same scenes without them, because extremal edge boundaries explicitly indicate an image's end (i.e., they do not continue past the view boundary). A large and a small difference (16 % and 40 %) between the close and wide-angle views shown during the experiment were tested to examine the effects of both boundary extension and normalization with and without extremal edges. Images without extremal edges elicited typical boundary extension for the 16 % size change condition, whereas the 40 % condition showed signs of normalization. With extremal edges, a reduced amount of boundary extension occurred for the 16 % condition, and only normalization was found for the 40 % condition. Our findings support and highlight the importance of amodal continuation at the view boundaries as a component of boundary extension.

  12. Definitive intraoperative very high-dose radiotherapy for localized osteosarcoma in the extremities

    International Nuclear Information System (INIS)

    Oya, Natsuo; Kokubo, Masaki; Mizowaki, Takashi; Shibamoto, Yuta; Nagata, Yasushi; Sasai, Keisuke; Nishimura, Yasumasa; Tsuboyama, Tadao; Toguchida, Junya; Nakamura, Takashi; Hiraoka, Masahiro

    2001-01-01

    Purpose: To evaluate the outcome and adverse effects in patients with osteosarcoma treated with very high-dose definitive intraoperative radiotherapy (IORT), with the intention of saving the affected limb. Methods and Materials: Thirty-nine patients with osteosarcoma in their extremities were treated with definitive IORT. The irradiation field included the tumor plus an adequate wide margin and excluded the major vessels and nerves. Forty-five to 80 Gy of electrons or X-rays were delivered. The median follow-up of the surviving patients was 124 months. Results: The cause-specific and relapse-free 5-year survival rate was 50% and 43%, respectively. Distant metastasis developed in 23 patients; 19 died and 4 were alive for >10 years. Nine local recurrences were found 4-29 months after IORT in the affected limb. No radiation-induced skin reaction or nerve palsy was observed in the patients treated with X-rays. Experiments using phantoms also confirmed that the scatter dose was below the toxic level in the IORT setting with X-rays. Conclusions: Very high-dose definitive IORT combined with preventive nailing and chemotherapy appeared to be a promising quality-of-life-oriented alternative to treating patients with osteosarcomas in the extremities, although the problem of recurrences from the surrounding unirradiated soft tissue remains to be solved

  13. The influence of non thermal coherent EMR with low intensity and extremely high frequency on total activity and isoenzyme composition of peroxidase

    International Nuclear Information System (INIS)

    Nerkararyan, A.V.; Shahinyan, M.A.; Khachatryan, A.V.; Vardevanyan, P.O.

    2011-01-01

    In this work the influence of non-thermal coherent electromagnetic radiation (EMR) with low intensity and extremely high frequency on intensity of wheat developing germ metabolism has been investigated. Particularly, total activity and isoenzymatic composition of peroxidase of germ cells have been determined during their growth. The role of water in formation of organism response reaction to the external physical field effect has also been investigated. It has been shown, that water appears to be a primary element of extremely high frequency EMR effect on bio system. Extremely high frequency EMR irradiation of germinating seeds and the cultivation of dry seeds and their germs by irradiated water stimulate peroxidase synthesis in germ cells. The redistribution of quantitative composition of peroxidase molecular forms takes place in germ cells effected by EMR with extremely high frequency and low intensity

  14. Extreme-Environment Silicon-Carbide (SiC) Wireless Sensor Suite

    Science.gov (United States)

    Yang, Jie

    2015-01-01

    Phase II objectives: Develop an integrated silicon-carbide wireless sensor suite capable of in situ measurements of critical characteristics of NTP engine; Compose silicon-carbide wireless sensor suite of: Extreme-environment sensors center, Dedicated high-temperature (450 deg C) silicon-carbide electronics that provide power and signal conditioning capabilities as well as radio frequency modulation and wireless data transmission capabilities center, An onboard energy harvesting system as a power source.

  15. Fiber Bragg Grating Dilatometry in Extreme Magnetic Field and Cryogenic Conditions

    Directory of Open Access Journals (Sweden)

    Marcelo Jaime

    2017-11-01

    Full Text Available In this work, we review single mode SiO2 fiber Bragg grating techniques for dilatometry studies of small single-crystalline samples in the extreme environments of very high, continuous, and pulsed magnetic fields of up to 150 T and at cryogenic temperatures down to <1 K. Distinct millimeter-long materials are measured as part of the technique development, including metallic, insulating, and radioactive compounds. Experimental strategies are discussed for the observation and analysis of the related thermal expansion and magnetostriction of materials, which can achieve a strain sensitivity (ΔL/L as low as a few parts in one hundred million (≈10−8. The impact of experimental artifacts, such as those originating in the temperature dependence of the fiber’s index of diffraction, light polarization rotation in magnetic fields, and reduced strain transfer from millimeter-long specimens, is analyzed quantitatively using analytic models available in the literature. We compare the experimental results with model predictions in the small-sample limit, and discuss the uncovered discrepancies.

  16. Extremely low temperature properties of epoxy GFRP

    International Nuclear Information System (INIS)

    Kadotani, Kenzo; Nagai, Matao; Aki, Fumitake.

    1983-01-01

    The examination of fiber-reinforced plastics, that is, plastics such as epoxy, polyester and polyimide reinforced with high strength fibers such as glass, carbon, boron and steel, for extremely low temperature use began from the fuel tanks of rockets. Therafter, the trial manufacture of superconducting generators and extremely low temperature transformers and the manufacture of superconducting magnets for nuclear fusion experimental setups became active, and high performance FRPs have been adopted, of which the extremely low temperature properties have been sufficiently grasped. Recently, the cryostats made of FRPs have been developed, fully utilizing such features of FRPs as high strength, high rigidity, non-magnetic material, insulation, low heat conductivity, light weight and the freedom of molding. In this paper, the mechanical properties at extremely low temperature of the plastic composite materials used as insulators and structural materials for extremely low temperature superconducting equipment is outlined, and in particular, glass fiber-reinforced epoxy laminates are described somewhat in detail. The fracture strain of GFRP at extremely low temperature is about 1.3 times as large as that at room temperature, but at extremely low temperature, clear cracking occurred at 40% of the fracture strain. The linear thermal contraction of GFRP showed remarkable anisotropy. (Kako, I.)

  17. Extreme events in total ozone over Arosa – Part 1: Application of extreme value theory

    Directory of Open Access Journals (Sweden)

    H. E. Rieder

    2010-10-01

    Full Text Available In this study ideas from extreme value theory are for the first time applied in the field of stratospheric ozone research, because statistical analysis showed that previously used concepts assuming a Gaussian distribution (e.g. fixed deviations from mean values of total ozone data do not adequately address the structure of the extremes. We show that statistical extreme value methods are appropriate to identify ozone extremes and to describe the tails of the Arosa (Switzerland total ozone time series. In order to accommodate the seasonal cycle in total ozone, a daily moving threshold was determined and used, with tools from extreme value theory, to analyse the frequency of days with extreme low (termed ELOs and high (termed EHOs total ozone at Arosa. The analysis shows that the Generalized Pareto Distribution (GPD provides an appropriate model for the frequency distribution of total ozone above or below a mathematically well-defined threshold, thus providing a statistical description of ELOs and EHOs. The results show an increase in ELOs and a decrease in EHOs during the last decades. The fitted model represents the tails of the total ozone data set with high accuracy over the entire range (including absolute monthly minima and maxima, and enables a precise computation of the frequency distribution of ozone mini-holes (using constant thresholds. Analyzing the tails instead of a small fraction of days below constant thresholds provides deeper insight into the time series properties. Fingerprints of dynamical (e.g. ENSO, NAO and chemical features (e.g. strong polar vortex ozone loss, and major volcanic eruptions, can be identified in the observed frequency of extreme events throughout the time series. Overall the new approach to analysis of extremes provides more information on time series properties and variability than previous approaches that use only monthly averages and/or mini-holes and mini-highs.

  18. Industrial Coatings at Extreme Conditions

    DEFF Research Database (Denmark)

    Subramanian, Srinath; Pérez Hornero, Clara; Pedersen, Lars Thorslund

    With the gradual depletion of oil wells operable at relatively lower temperatures and pressures, the upstream oil industry relies on High Pressure High Temperature (HPHT) wells to source crude oil and gas. HPHT well extraction and processing require anticorrosive coatings applied on substrates...

  19. Possible alternatives to critical elements in coatings for extreme applications

    Science.gov (United States)

    Grilli, Maria Luisa; Valerini, Daniele; Piticescu, Radu Robert; Bellezze, Tiziano; Yilmaz, Mehmet; Rinaldi, Antonio; Cuesta-López, Santiago; Rizzo, Antonella

    2018-03-01

    Surface functionalisation and protection have been used since a long time for improving specific properties of materials such as lubrication, water repellence, brightness, and for increasing durability of objects and tools. Among the different kinds of surface treatments used to achieve the required properties, the use of coatings is fundamental to guarantee substrate durability in harsh environments. Extreme working conditions of temperature, pressure, irradiation, wear and corrosion occur in several applications, thus very often requiring bulk material protection by means of coatings. In this study, three main classes of coatings used in extreme conditions are considered: i) hard and superhard coatings for application in machining tools, ii) coatings for high temperatures (thermal barrier coatings), and iii) coatings against corrosion. The presence of critical elements in such coatings (Cr, Y, W, Co, etc.) is analysed and the possibility to use CRMs-free substitutes is reviewed. The role of multilayers and nanocomposites in tailoring coating performances is also discussed for thermal barrier and superhard coatings.

  20. Decolorisation of Congo Red by Aeromonas hydrophila Under Microaerophilic Conditions

    International Nuclear Information System (INIS)

    El Gizawy, S.; Refae, R.A.; Abd El Kareem, H.; Gomaa, O.M.; Hamed, H.

    2009-01-01

    Among 22 local bacterial isolates, Aeromonas hydrophila isolated from Bolti fish showed a remarkable ability to decolorize congo red under microaerophilic conditions (98.8% in 48 hrs) without prior adaptation. The bacterium had the ability to grow and decolorized high concentrations of congo red which varied from 50 to 1000 mg/l , the decolorisation was irrelevant to bacterial growth. The strain was capable of decolorizing congo red under a wide range of temperatures (20-40 degree C), ph (3-8), NaCl (0-200 mg/l) and also had the ability to decolorized mono, di and poly azo dyes. This bacterium is notable in its ability to decolorized the diazo congo red under extreme conditions of temperature, ph, salinity and high dye concentrations which makes it suitable for decolorisation under extreme industrial conditions

  1. CLASH: EXTREME EMISSION-LINE GALAXIES AND THEIR IMPLICATION ON SELECTION OF HIGH-REDSHIFT GALAXIES

    International Nuclear Information System (INIS)

    Huang, Xingxing; Wang, Junxian; Shu, Xinwen; Zheng, Wei; Ford, Holland; Lemze, Doron; Moustakas, John; Van der Wel, Arjen; Zitrin, Adi; Frye, Brenda L.; Postman, Marc; Bradley, Larry; Coe, Dan; Bartelmann, Matthias; Benítez, Narciso; Broadhurst, Tom; Donahue, Megan; Infante, Leopoldo

    2015-01-01

    We utilize the Cluster Lensing And Supernova survey with Hubble observations of 25 clusters to search for extreme emission-line galaxies (EELGs). The selections are carried out in two central bands: F105W (Y 105 ) and F125W (J 125 ), as the flux of the central bands could be enhanced by the presence of [O III] λλ4959, 5007 at redshifts of ∼0.93-1.14 and 1.57-1.79, respectively. The multiband observations help to constrain the equivalent widths (EWs) of emission lines. Thanks to cluster lensing, we are able to identify 52 candidates down to an intrinsic limiting magnitude of 28.5 and to a rest-frame [O III] λλ4959, 5007 EW of ≅ 3700 Å. Our samples include a number of EELGs at lower luminosities that are missed in other surveys, and the extremely high EW can only be found in such faint galaxies. These EELGs can mimic a dropout feature similar to that of high-redshift galaxies and contaminate the color-color selection of high-redshift galaxies when the signal-to-noise ratio is limited or the band coverage is incomplete

  2. CLASH: EXTREME EMISSION-LINE GALAXIES AND THEIR IMPLICATION ON SELECTION OF HIGH-REDSHIFT GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xingxing; Wang, Junxian; Shu, Xinwen [CAS Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zheng, Wei; Ford, Holland; Lemze, Doron [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Moustakas, John [Department of Physics and Astronomy, Siena College, 515 Loudon Road, Loudonville, NY 12211 (United States); Van der Wel, Arjen [Max-Planck Institute for Astronomy, Königstuhl 17, D-69117, Heidelberg (Germany); Zitrin, Adi [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); Frye, Brenda L. [Steward Observatory/Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Postman, Marc; Bradley, Larry; Coe, Dan [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21208 (United States); Bartelmann, Matthias [Leiden Observatory, Leiden University, P. O. Box 9513, 2300 RA Leiden (Netherlands); Benítez, Narciso [Instituto de Astrofísica de Andalucía (CSIC), C/Camino Bajo de Huétor 24, Granada E-18008 (Spain); Broadhurst, Tom [Department of Theoretical Physics, University of Basque Country UPV/EHU E-Bilbao (Spain); Donahue, Megan [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Infante, Leopoldo, E-mail: hxx@mail.ustc.edu.cn [Departamento de Astronoía y Astrofísica, Pontificia Universidad Católica de Chile, V. Mackenna 4860 Santiago 22 (Chile); and others

    2015-03-01

    We utilize the Cluster Lensing And Supernova survey with Hubble observations of 25 clusters to search for extreme emission-line galaxies (EELGs). The selections are carried out in two central bands: F105W (Y {sub 105}) and F125W (J {sub 125}), as the flux of the central bands could be enhanced by the presence of [O III] λλ4959, 5007 at redshifts of ∼0.93-1.14 and 1.57-1.79, respectively. The multiband observations help to constrain the equivalent widths (EWs) of emission lines. Thanks to cluster lensing, we are able to identify 52 candidates down to an intrinsic limiting magnitude of 28.5 and to a rest-frame [O III] λλ4959, 5007 EW of ≅ 3700 Å. Our samples include a number of EELGs at lower luminosities that are missed in other surveys, and the extremely high EW can only be found in such faint galaxies. These EELGs can mimic a dropout feature similar to that of high-redshift galaxies and contaminate the color-color selection of high-redshift galaxies when the signal-to-noise ratio is limited or the band coverage is incomplete.

  3. Arctic sea ice, Eurasia snow, and extreme winter haze in China.

    Science.gov (United States)

    Zou, Yufei; Wang, Yuhang; Zhang, Yuzhong; Koo, Ja-Ho

    2017-03-01

    The East China Plains (ECP) region experienced the worst haze pollution on record for January in 2013. We show that the unprecedented haze event is due to the extremely poor ventilation conditions, which had not been seen in the preceding three decades. Statistical analysis suggests that the extremely poor ventilation conditions are linked to Arctic sea ice loss in the preceding autumn and extensive boreal snowfall in the earlier winter. We identify the regional circulation mode that leads to extremely poor ventilation over the ECP region. Climate model simulations indicate that boreal cryospheric forcing enhances the regional circulation mode of poor ventilation in the ECP region and provides conducive conditions for extreme haze such as that of 2013. Consequently, extreme haze events in winter will likely occur at a higher frequency in China as a result of the changing boreal cryosphere, posing difficult challenges for winter haze mitigation but providing a strong incentive for greenhouse gas emission reduction.

  4. Climate extremes promote fatal co-infections during canine distemper epidemics in African lions.

    Science.gov (United States)

    Munson, Linda; Terio, Karen A; Kock, Richard; Mlengeya, Titus; Roelke, Melody E; Dubovi, Edward; Summers, Brian; Sinclair, Anthony R E; Packer, Craig

    2008-06-25

    Extreme climatic conditions may alter historic host-pathogen relationships and synchronize the temporal and spatial convergence of multiple infectious agents, triggering epidemics with far greater mortality than those due to single pathogens. Here we present the first data to clearly illustrate how climate extremes can promote a complex interplay between epidemic and endemic pathogens that are normally tolerated in isolation, but with co-infection, result in catastrophic mortality. A 1994 canine distemper virus (CDV) epidemic in Serengeti lions (Panthera leo) coincided with the death of a third of the population, and a second high-mortality CDV epidemic struck the nearby Ngorongoro Crater lion population in 2001. The extent of adult mortalities was unusual for CDV and prompted an investigation into contributing factors. Serological analyses indicated that at least five "silent" CDV epidemics swept through the same two lion populations between 1976 and 2006 without clinical signs or measurable mortality, indicating that CDV was not necessarily fatal. Clinical and pathology findings suggested that hemoparsitism was a major contributing factor during fatal epidemics. Using quantitative real-time PCR, we measured the magnitude of hemoparasite infections in these populations over 22 years and demonstrated significantly higher levels of Babesia during the 1994 and 2001 epidemics. Babesia levels correlated with mortalities and extent of CDV exposure within prides. The common event preceding the two high mortality CDV outbreaks was extreme drought conditions with wide-spread herbivore die-offs, most notably of Cape buffalo (Syncerus caffer). As a consequence of high tick numbers after the resumption of rains and heavy tick infestations of starving buffalo, the lions were infected by unusually high numbers of Babesia, infections that were magnified by the immunosuppressive effects of coincident CDV, leading to unprecedented mortality. Such mass mortality events may become

  5. Climate extremes promote fatal co-infections during canine distemper epidemics in African lions.

    Directory of Open Access Journals (Sweden)

    Linda Munson

    Full Text Available Extreme climatic conditions may alter historic host-pathogen relationships and synchronize the temporal and spatial convergence of multiple infectious agents, triggering epidemics with far greater mortality than those due to single pathogens. Here we present the first data to clearly illustrate how climate extremes can promote a complex interplay between epidemic and endemic pathogens that are normally tolerated in isolation, but with co-infection, result in catastrophic mortality. A 1994 canine distemper virus (CDV epidemic in Serengeti lions (Panthera leo coincided with the death of a third of the population, and a second high-mortality CDV epidemic struck the nearby Ngorongoro Crater lion population in 2001. The extent of adult mortalities was unusual for CDV and prompted an investigation into contributing factors. Serological analyses indicated that at least five "silent" CDV epidemics swept through the same two lion populations between 1976 and 2006 without clinical signs or measurable mortality, indicating that CDV was not necessarily fatal. Clinical and pathology findings suggested that hemoparsitism was a major contributing factor during fatal epidemics. Using quantitative real-time PCR, we measured the magnitude of hemoparasite infections in these populations over 22 years and demonstrated significantly higher levels of Babesia during the 1994 and 2001 epidemics. Babesia levels correlated with mortalities and extent of CDV exposure within prides. The common event preceding the two high mortality CDV outbreaks was extreme drought conditions with wide-spread herbivore die-offs, most notably of Cape buffalo (Syncerus caffer. As a consequence of high tick numbers after the resumption of rains and heavy tick infestations of starving buffalo, the lions were infected by unusually high numbers of Babesia, infections that were magnified by the immunosuppressive effects of coincident CDV, leading to unprecedented mortality. Such mass mortality

  6. Climate Extremes Promote Fatal Co-Infections during Canine Distemper Epidemics in African Lions

    Science.gov (United States)

    Munson, Linda; Terio, Karen A.; Kock, Richard; Mlengeya, Titus; Roelke, Melody E.; Dubovi, Edward; Summers, Brian; Sinclair, Anthony R. E.; Packer, Craig

    2008-01-01

    Extreme climatic conditions may alter historic host-pathogen relationships and synchronize the temporal and spatial convergence of multiple infectious agents, triggering epidemics with far greater mortality than those due to single pathogens. Here we present the first data to clearly illustrate how climate extremes can promote a complex interplay between epidemic and endemic pathogens that are normally tolerated in isolation, but with co-infection, result in catastrophic mortality. A 1994 canine distemper virus (CDV) epidemic in Serengeti lions (Panthera leo) coincided with the death of a third of the population, and a second high-mortality CDV epidemic struck the nearby Ngorongoro Crater lion population in 2001. The extent of adult mortalities was unusual for CDV and prompted an investigation into contributing factors. Serological analyses indicated that at least five “silent” CDV epidemics swept through the same two lion populations between 1976 and 2006 without clinical signs or measurable mortality, indicating that CDV was not necessarily fatal. Clinical and pathology findings suggested that hemoparsitism was a major contributing factor during fatal epidemics. Using quantitative real-time PCR, we measured the magnitude of hemoparasite infections in these populations over 22 years and demonstrated significantly higher levels of Babesia during the 1994 and 2001 epidemics. Babesia levels correlated with mortalities and extent of CDV exposure within prides. The common event preceding the two high mortality CDV outbreaks was extreme drought conditions with wide-spread herbivore die-offs, most notably of Cape buffalo (Syncerus caffer). As a consequence of high tick numbers after the resumption of rains and heavy tick infestations of starving buffalo, the lions were infected by unusually high numbers of Babesia, infections that were magnified by the immunosuppressive effects of coincident CDV, leading to unprecedented mortality. Such mass mortality events may

  7. Local likelihood estimation of complex tail dependence structures in high dimensions, applied to US precipitation extremes

    KAUST Repository

    Camilo, Daniela Castro

    2017-10-02

    In order to model the complex non-stationary dependence structure of precipitation extremes over the entire contiguous U.S., we propose a flexible local approach based on factor copula models. Our sub-asymptotic spatial modeling framework yields non-trivial tail dependence structures, with a weakening dependence strength as events become more extreme, a feature commonly observed with precipitation data but not accounted for in classical asymptotic extreme-value models. To estimate the local extremal behavior, we fit the proposed model in small regional neighborhoods to high threshold exceedances, under the assumption of local stationarity. This allows us to gain in flexibility, while making inference for such a large and complex dataset feasible. Adopting a local censored likelihood approach, inference is made on a fine spatial grid, and local estimation is performed taking advantage of distributed computing resources and of the embarrassingly parallel nature of this estimation procedure. The local model is efficiently fitted at all grid points, and uncertainty is measured using a block bootstrap procedure. An extensive simulation study shows that our approach is able to adequately capture complex, non-stationary dependencies, while our study of U.S. winter precipitation data reveals interesting differences in local tail structures over space, which has important implications on regional risk assessment of extreme precipitation events. A comparison between past and current data suggests that extremes in certain areas might be slightly wider in extent nowadays than during the first half of the twentieth century.

  8. Local likelihood estimation of complex tail dependence structures in high dimensions, applied to US precipitation extremes

    KAUST Repository

    Camilo, Daniela Castro; Huser, Raphaë l

    2017-01-01

    In order to model the complex non-stationary dependence structure of precipitation extremes over the entire contiguous U.S., we propose a flexible local approach based on factor copula models. Our sub-asymptotic spatial modeling framework yields non-trivial tail dependence structures, with a weakening dependence strength as events become more extreme, a feature commonly observed with precipitation data but not accounted for in classical asymptotic extreme-value models. To estimate the local extremal behavior, we fit the proposed model in small regional neighborhoods to high threshold exceedances, under the assumption of local stationarity. This allows us to gain in flexibility, while making inference for such a large and complex dataset feasible. Adopting a local censored likelihood approach, inference is made on a fine spatial grid, and local estimation is performed taking advantage of distributed computing resources and of the embarrassingly parallel nature of this estimation procedure. The local model is efficiently fitted at all grid points, and uncertainty is measured using a block bootstrap procedure. An extensive simulation study shows that our approach is able to adequately capture complex, non-stationary dependencies, while our study of U.S. winter precipitation data reveals interesting differences in local tail structures over space, which has important implications on regional risk assessment of extreme precipitation events. A comparison between past and current data suggests that extremes in certain areas might be slightly wider in extent nowadays than during the first half of the twentieth century.

  9. Delayed responses of an Arctic ecosystem to an extremely dry summer: impacts on net ecosystem exchange and vegetation functioning

    Science.gov (United States)

    Zona, D.; Lipson, D. A.; Richards, J. H.; Phoenix, G. K.; Liljedahl, A. K.; Ueyama, M.; Sturtevant, C. S.; Oechel, W. C.

    2013-12-01

    The importance and mode of action of extreme events on the global carbon budget are inadequately understood. This includes the differential impact of extreme events on various ecosystem components, lag effects, recovery times, and compensatory processes. Summer 2007 in Barrow, Arctic Alaska, experienced unusually high air temperatures (fifth warmest over a 65 yr period) and record low precipitation (lowest over a 65 yr period). These abnormal conditions resulted in strongly reduced net Sphagnum CO2 uptake, but no effect neither on vascular plant development nor on net ecosystem exchange (NEE) from this arctic tundra ecosystem. Gross primary production (GPP) and ecosystem respiration (Reco) were both generally greater during most of this extreme summer. Cumulative ecosystem C uptake in 2007 was similar to the previous summers, showing the capacity of the ecosystem to compensate in its net ecosystem exchange (NEE) despite the impact on other functions and structure such as substantial necrosis of the Sphagnum layer. Surprisingly, the lowest ecosystem C uptake (2005-2009) was observed during the 2008 summer, i.e the year directly following the extremely summer. In 2008, cumulative C uptake was ∼70% lower than prior years. This reduction cannot solely be attributed to mosses, which typically contribute with ∼40% - of the entire ecosystem C uptake. The minimum summer cumulative C uptake in 2008 suggests that the entire ecosystem experienced difficulty readjusting to more typical weather after experiencing exceptionally warm and dry conditions. Importantly, the return to a substantial cumulative C uptake occurred two summers after the extreme event, which suggest a high resilience of this tundra ecosystem. Overall, these results show a highly complex response of the C uptake and its sub-components to atypically dry conditions. The impact of multiple extreme events still awaits further investigation.

  10. Nitrogen accumulation and partitioning in a High Arctic tundra ecosystem from extreme atmospheric N deposition events

    International Nuclear Information System (INIS)

    Choudhary, Sonal; Blaud, Aimeric; Osborn, A. Mark; Press, Malcolm C.; Phoenix, Gareth K.

    2016-01-01

    Arctic ecosystems are threatened by pollution from recently detected extreme atmospheric nitrogen (N) deposition events in which up to 90% of the annual N deposition can occur in just a few days. We undertook the first assessment of the fate of N from extreme deposition in High Arctic tundra and are presenting the results from the whole ecosystem "1"5N labelling experiment. In 2010, we simulated N depositions at rates of 0, 0.04, 0.4 and 1.2 g N m"−"2 yr"−"1, applied as "1"5NH_4"1"5NO_3 in Svalbard (79"°N), during the summer. Separate applications of "1"5NO_3"− and "1"5NH_4"+ were also made to determine the importance of N form in their retention. More than 95% of the total "1"5N applied was recovered after one growing season (~ 90% after two), demonstrating a considerable capacity of Arctic tundra to retain N from these deposition events. Important sinks for the deposited N, regardless of its application rate or form, were non-vascular plants > vascular plants > organic soil > litter > mineral soil, suggesting that non-vascular plants could be the primary component of this ecosystem to undergo measurable changes due to N enrichment from extreme deposition events. Substantial retention of N by soil microbial biomass (70% and 39% of "1"5N in organic and mineral horizon, respectively) during the initial partitioning demonstrated their capacity to act as effective buffers for N leaching. Between the two N forms, vascular plants (Salix polaris) in particular showed difference in their N recovery, incorporating four times greater "1"5NO_3"− than "1"5NH_4"+, suggesting deposition rich in nitrate will impact them more. Overall, these findings show that despite the deposition rates being extreme in statistical terms, biologically they do not exceed the capacity of tundra to sequester pollutant N during the growing season. Therefore, current and future extreme events may represent a major source of eutrophication. - Highlights: • High Arctic tundra demonstrated a

  11. Assessment extreme hydrometeorological conditions in the Gulf of Bothnia, the Baltic Sea

    Science.gov (United States)

    Dvornikov, Anton; Martyanov, Stanislav; Ryabchenko, Vladimir; Eremina, Tatjana; Isaev, Alexey; Sein, Dmitry

    2017-04-01

    Extreme hydrometeorological conditions in the Gulf of Bothnia, the Baltic Sea, are estimated paying a special attention to the area of the future construction of nuclear power plant (NPP) "Hanhikivi-1" (24° 16' E, 64° 32' N). To produce these estimates, long-term observations and results from numerical models of water and ice circulation and wind waves are used. It is estimated that the average annual air temperature in the vicinity of the station is +3° C, summer and winter extreme temperature is equal to 33.3° C and -41.5° C, respectively. Model calculations of wind waves have shown that the most dangerous (in terms of the generation of wind waves in the NPP area) is a north-west wind with the direction of 310°. The maximum height of the waves in the Gulf of Bothnia near the NPP for this wind direction with wind velocity of 10 m/s is 1.2-1.4 m. According to the model estimates, the highest possible level of the sea near the NPP is 248 cm, the minimum level, -151 cm, respectively for the western and eastern winds. These estimates are in good agreement with observations on the sea level for the period 1922-2015 at the nearest hydrometeorological station Raahe (Finland). In order to assess the likely impact of the NPP on the marine environment numerical experiments for the cold (2010) and warm year (2014) have been carried out. These calculations have shown that permanent release of heat into the marine environment from the operating NPP for the cold year (2010) will increase the temperature in the upper layer of 0-250m zone by 10°C in winter - spring and by 8°C in summer - early autumn, and in the bottom layer of 0-250m zone by 5°C in winter - spring and 3°C in summer - early autumn. For the warm year (2014), these temperature changes are smaller. Ice cover in both cases will disappear in two - kilometer vicinity of the NPP. These effects should be taken into account when assessing local climate changes in the future

  12. Combined dendro-documentary evidence of Central European hydroclimatic springtime extremes over the last millennium

    Science.gov (United States)

    Büntgen, Ulf; Brázdil, Rudolf; Heussner, Karl-Uwe; Hofmann, Jutta; Kontic, Raymond; Kyncl, Tomáš; Pfister, Christian; Chromá, Kateřina; Tegel, Willy

    2011-12-01

    A predicted rise in anthropogenic greenhouse gas emissions and associated effects on the Earth's climate system likely imply more frequent and severe weather extremes with alternations in hydroclimatic parameters expected to be most critical for ecosystem functioning, agricultural yield, and human health. Evaluating the return period and amplitude of modern climatic extremes in light of pre-industrial natural changes is, however, limited by generally too short instrumental meteorological observations. Here we introduce and analyze 11,873 annually resolved and absolutely dated ring width measurement series from living and historical fir ( Abies alba Mill.) trees sampled across France, Switzerland, Germany, and the Czech Republic, which continuously span the AD 962-2007 period. Even though a dominant climatic driver of European fir growth was not found, ring width extremes were evidently triggered by anomalous variations in Central European April-June precipitation. Wet conditions were associated with dynamic low-pressure cells, whereas continental-scale droughts coincided with persistent high-pressure between 35 and 55°N. Documentary evidence independently confirms many of the dendro signals over the past millennium, and further provides insight on causes and consequences of ambient weather conditions related to the reconstructed extremes. A fairly uniform distribution of hydroclimatic extremes throughout the Medieval Climate Anomaly, Little Ice Age and Recent Global Warming may question the common believe that frequency and severity of such events closely relates to climate mean stages. This joint dendro-documentary approach not only allows extreme climate conditions of the industrial era to be placed against the backdrop of natural variations, but also probably helps to constrain climate model simulations over exceptional long timescales.

  13. Extreme ultraviolet spectroscopy of highly charged argon ions at the Berlin EBIT

    International Nuclear Information System (INIS)

    Biedermann, C; Radtke, R; Fussmann, G; Allen, F I

    2007-01-01

    Extreme ultraviolet radiation from highly charged argon was investigated at the Berlin Electron Beam Ion Trap with a 2 m grazing incidence spectrometer. Lines in the wavelength range 150 to 660 A originating from C-like Ar 12+ to Li-like Ar 15+ ions have been identified and are compared with database information from solar line lists and predictions. Line ratios for the observed resonance, intercombination and forbidden lines offer important diagnostic capabilities for low density, hot plasmas

  14. Extremely Stable Polypyrrole Achieved via Molecular Ordering for Highly Flexible Supercapacitors.

    Science.gov (United States)

    Huang, Yan; Zhu, Minshen; Pei, Zengxia; Huang, Yang; Geng, Huiyuan; Zhi, Chunyi

    2016-01-27

    The cycling stability of flexible supercapacitors with conducting polymers as electrodes is limited by the structural breakdown arising from repetitive counterion flow during charging/discharging. Supercapacitors made of facilely electropolymerized polypyrrole (e-PPy) have ultrahigh capacitance retentions of more than 97, 91, and 86% after 15000, 50000, and 100000 charging/discharging cycles, respectively, and can sustain more than 230000 charging/discharging cycles with still approximately half of the initial capacitance retained. To the best of our knowledge, such excellent long-term cycling stability was never reported. The fully controllable electropolymerization shows superiority in molecular ordering, favoring uniform stress distribution and charge transfer. Being left at ambient conditions for even 8 months, e-PPy supercapacitors completely retain the good electrochemical performance. The extremely stable supercapacitors with excellent flexibility and scalability hold considerable promise for the commerical application of flexible and wearable electronics.

  15. Numerical simulation of floating bodies in extreme free surface waves

    Directory of Open Access Journals (Sweden)

    Z. Z. Hu

    2011-02-01

    Full Text Available In this paper, we use the in-house Computational Fluid Dynamics (CFD flow code AMAZON-SC as a numerical wave tank (NWT to study wave loading on a wave energy converter (WEC device in heave motion. This is a surface-capturing method for two fluid flows that treats the free surface as contact surface in the density field that is captured automatically without special provision. A time-accurate artificial compressibility method and high resolution Godunov-type scheme are employed in both fluid regions (air/water. The Cartesian cut cell method can provide a boundary-fitted mesh for a complex geometry with no requirement to re-mesh globally or even locally for moving geometry, requiring only changes to cut cell data at the body contour. Extreme wave boundary conditions are prescribed in an empty NWT and compared with physical experiments prior to calculations of extreme waves acting on a floating Bobber-type device. The validation work also includes the wave force on a fixed cylinder compared with theoretical and experimental data under regular waves. Results include free surface elevations, vertical displacement of the float, induced vertical velocity and heave force for a typical Bobber geometry with a hemispherical base under extreme wave conditions.

  16. Rapid adaptation of microalgae to bodies of water with extreme pollution from uranium mining: An explanation of how mesophilic organisms can rapidly colonise extremely toxic environments

    Energy Technology Data Exchange (ETDEWEB)

    García-Balboa, C.; Baselga-Cervera, B. [Genetica, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid (Spain); García-Sanchez, A.; Igual, J.M. [Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA-CSIC), PO Box 257, 37071 Salamanca (Spain); Lopez-Rodas, V. [Genetica, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid (Spain); Costas, E., E-mail: ecostas@vet.ucm.es [Genetica, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid (Spain)

    2013-11-15

    Highlights: •Some microalgae species survive to extreme environments in ponds of residual waters from uranium mining. •Adaptation of microalgae to U arose very fast. •Spontaneous mutations that confer large adaptive value were able to produce the adaptation to residual waters of U mining. •Adaptation to more extreme waters of U mining is only possible after the recombination subsequent to sexual mating. •Resistant microalgae bio-adsorbs uranium to the cell wall and internalises uranium inside the cytoplasm. -- Abstract: Extreme environments may support communities of microalgae living at the limits of their tolerance. It is usually assumed that these extreme environments are inhabited by extremophile species. However, global anthropogenic environmental changes are generating new extreme environments, such as mining-effluent pools of residual waters from uranium mining with high U levels, acidity and radioactivity in Salamanca (Spain). Certain microalgal species have rapidly adapted to these extreme waters (uranium mining in this area began in 1960). Experiments have demonstrated that physiological acclimatisation would be unable to achieve adaptation. In contrast, rapid genetic adaptation was observed in waters ostensibly lethal to microalgae by means of rare spontaneous mutations that occurred prior to the exposure to effluent waters from uranium mining. However, adaptation to the most extreme conditions was only possible after recombination through sexual mating because adaptation requires more than one mutation. Microalgae living in extreme environments could be the descendants of pre-selective mutants that confer significant adaptive value to extreme contamination. These “lucky mutants” could allow for the evolutionary rescue of populations faced with rapid environmental change.

  17. Rapid adaptation of microalgae to bodies of water with extreme pollution from uranium mining: An explanation of how mesophilic organisms can rapidly colonise extremely toxic environments

    International Nuclear Information System (INIS)

    García-Balboa, C.; Baselga-Cervera, B.; García-Sanchez, A.; Igual, J.M.; Lopez-Rodas, V.; Costas, E.

    2013-01-01

    Highlights: •Some microalgae species survive to extreme environments in ponds of residual waters from uranium mining. •Adaptation of microalgae to U arose very fast. •Spontaneous mutations that confer large adaptive value were able to produce the adaptation to residual waters of U mining. •Adaptation to more extreme waters of U mining is only possible after the recombination subsequent to sexual mating. •Resistant microalgae bio-adsorbs uranium to the cell wall and internalises uranium inside the cytoplasm. -- Abstract: Extreme environments may support communities of microalgae living at the limits of their tolerance. It is usually assumed that these extreme environments are inhabited by extremophile species. However, global anthropogenic environmental changes are generating new extreme environments, such as mining-effluent pools of residual waters from uranium mining with high U levels, acidity and radioactivity in Salamanca (Spain). Certain microalgal species have rapidly adapted to these extreme waters (uranium mining in this area began in 1960). Experiments have demonstrated that physiological acclimatisation would be unable to achieve adaptation. In contrast, rapid genetic adaptation was observed in waters ostensibly lethal to microalgae by means of rare spontaneous mutations that occurred prior to the exposure to effluent waters from uranium mining. However, adaptation to the most extreme conditions was only possible after recombination through sexual mating because adaptation requires more than one mutation. Microalgae living in extreme environments could be the descendants of pre-selective mutants that confer significant adaptive value to extreme contamination. These “lucky mutants” could allow for the evolutionary rescue of populations faced with rapid environmental change

  18. Projections of extreme water level events for atolls in the western Tropical Pacific

    Science.gov (United States)

    Merrifield, M. A.; Becker, J. M.; Ford, M.; Yao, Y.

    2014-12-01

    Conditions that lead to extreme water levels and coastal flooding are examined for atolls in the Republic of the Marshall Islands based on a recent field study of wave transformations over fringing reefs, tide gauge observations, and wave model hindcasts. Wave-driven water level extremes pose the largest threat to atoll shorelines, with coastal levels scaling as approximately one-third of the incident breaking wave height. The wave-driven coastal water level is partitioned into a mean setup, low frequency oscillations associated with cross-reef quasi-standing modes, and wind waves that reach the shore after undergoing high dissipation due to breaking and bottom friction. All three components depend on the water level over the reef; however, the sum of the components is independent of water level due to cancelling effects. Wave hindcasts suggest that wave-driven water level extremes capable of coastal flooding are infrequent events that require a peak wave event to coincide with mid- to high-tide conditions. Interannual and decadal variations in sea level do not change the frequency of these events appreciably. Future sea-level rise scenarios significantly increase the flooding threat associated with wave events, with a nearly exponential increase in flooding days per year as sea level exceeds 0.3 to 1.0 m above current levels.

  19. Quantification of Cation Sorption to Engineered Barrier Materials Under Extreme Conditions

    International Nuclear Information System (INIS)

    Powell, Brian; Schlautman, Mark; Rao, Linfeng; Nitsche, Heino; Gregorich, Kenneth

    2016-01-01

    The objective of this research is to examine mechanisms and thermodynamics of actinide sorption to engineered barrier materials (iron (oxyhydr)oxides and bentonite clay) for nuclear waste repositories under high temperature and high ionic strength conditions using a suite of macroscopic and microscopic techniques which will be coupled with interfacial reaction models. Gaining a mechanistic understanding of interfacial processes governing the sorption/sequestration of actinides at mineral-water interfaces is fundamental for the accurate prediction of actinide behavior in waste repositories. Although macroscale sorption data and various spectroscopic techniques have provided valuable information regarding speciation of actinides at solid-water interfaces, significant knowledge gaps still exist with respect to sorption mechanisms and the ability to quantify sorption, particularly at high temperatures and ionic strengths. This objective is addressed through three major tasks: (1) influence of oxidation state on actinide sorption to iron oxides and clay minerals at elevated temperatures and ionic strengths; (2) calorimetric titrations of actinide-mineral suspensions; (3) evaluation of bentonite performance under repository conditions. The results of the work will include a qualitative conceptual model and a quantitative thermodynamic speciation model describing actinide partitioning to minerals and sediments, which is based upon a mechanistic understanding of specific sorption processes as determined from both micro-scale and macroscale experimental techniques. The speciation model will be a thermodynamic aqueous and surface complexation model of actinide interactions with mineral surfaces that is self-consistent with macroscopic batch sorption data, calorimetric and potentiometric titrations, X-ray absorption Spectroscopy (XAS, mainly Extended X-ray Absorption Fine Structure (EXAFS)), and electron microscopy analyses. The novelty of the proposed work lies largely in

  20. Quantification of Cation Sorption to Engineered Barrier Materials Under Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Powell, Brian [Clemson Univ., SC (United States); Schlautman, Mark [Clemson Univ., SC (United States); Rao, Linfeng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nitsche, Heino [Univ. of California, Berkeley, CA (United States); Gregorich, Kenneth [Univ. of California, Berkeley, CA (United States)

    2016-02-02

    The objective of this research is to examine mechanisms and thermodynamics of actinide sorption to engineered barrier materials (iron (oxyhydr)oxides and bentonite clay) for nuclear waste repositories under high temperature and high ionic strength conditions using a suite of macroscopic and microscopic techniques which will be coupled with interfacial reaction models. Gaining a mechanistic understanding of interfacial processes governing the sorption/sequestration of actinides at mineral-water interfaces is fundamental for the accurate prediction of actinide behavior in waste repositories. Although macroscale sorption data and various spectroscopic techniques have provided valuable information regarding speciation of actinides at solid-water interfaces, significant knowledge gaps still exist with respect to sorption mechanisms and the ability to quantify sorption, particularly at high temperatures and ionic strengths. This objective is addressed through three major tasks: (1) influence of oxidation state on actinide sorption to iron oxides and clay minerals at elevated temperatures and ionic strengths; (2) calorimetric titrations of actinide-mineral suspensions; (3) evaluation of bentonite performance under repository conditions. The results of the work will include a qualitative conceptual model and a quantitative thermodynamic speciation model describing actinide partitioning to minerals and sediments, which is based upon a mechanistic understanding of specific sorption processes as determined from both micro-scale and macroscale experimental techniques. The speciation model will be a thermodynamic aqueous and surface complexation model of actinide interactions with mineral surfaces that is self-consistent with macroscopic batch sorption data, calorimetric and potentiometric titrations, X-ray absorption Spectroscopy (XAS, mainly Extended X-ray Absorption Fine Structure (EXAFS)), and electron microscopy analyses. The novelty of the proposed work lies largely in

  1. Microsystem for remote sensing of high energy radiation with associated extremely low photon flux densities

    Science.gov (United States)

    Otten, A.; Jain, V. K.

    2015-08-01

    This paper presents a microsystem for remote sensing of high energy radiation in extremely low flux density conditions. With wide deployment in mind, potential applications range from nuclear non-proliferation, to hospital radiation-safety. The daunting challenge is the low level of photon flux densities - emerging from a Scintillation Crystal (SC) on to a ~1 mm-square detector, which are a factor of 10000 or so lower than those acceptable to recently reported photonic chips (including `single-photon detection' chips), due to a combination of low Lux, small detector size, and short duration SC output pulses - on the order of 1 μs. These challenges are attempted to be overcome by the design of an innovative `System on a Chip' type microchip, with high detector sensitivity, and effective coupling from the SC to the photodetector. The microchip houses a tiny n+ diff p-epi photodiode (PD) as well as the associated analog amplification and other related circuitry, all fabricated in 0.5micron, 3-metal 2-poly CMOS technology. The amplification, together with pulse-shaping of the photocurrent-induced voltage signal, is achieved through a tandem of two capacitively coupled, double-cascode amplifiers. Included in the paper are theoretical estimates and experimental results.

  2. The impact of extreme weather conditions on the life of settlers in the Central Russia in X - XVI centuries

    Science.gov (United States)

    Graves, Irina; Nizovtsev, Viacheslav; Erman, Natalia

    2017-04-01

    A special place in the reconstruction of climate dynamics takes an analysis of extraordinary meteorological phenomena. These extreme weather events in the first place impact the functioning of, the rhythm and dynamics of the landscapes and determine not only the features of economy, but also certain aspects of historical development. In the analysis of primary chronicles and published data, along with the direct climatic characteristics (hot, warm, cold, wet, dry, etc.) a lot of attention was paid to abnormal (extreme) natural phenomena and indirect indications of climate variability (floods, crop failures, hunger years, epidemics, etc.). As a result, tables were compiled reflecting climatic basic characteristics and extremes for each year since 900 BC. X-XI centuries was a period of minor climatic optimum - the climate was warmer and drier than the modern one. In addition to higher temperatures (up to 1-3C above than mordern), during this period there were no severe winters. A small amount of summer rainfall has led to a reduction in the number of small water reservoirs and flooding rivers. This is evidenced by Slavic settlements on floodplains of a number of rivers in the Moscow region. It is in this favorable climatic time the way "from the Vikings to the Greeks" was open. Catastrophic natural events had a minimum repeatability. For example, during the X century the Russian chronicles mentioned 41 extreme event, but for the XIII century - 102. Most of the villages and towns were located on the low floodplain terraces of rivers. The main farmland was concentrated there as well. In the "period of contrasts" (XIII - XIV centuries) there was an increase of intra-seasonal climate variability, humidity and widespread reduction in summer temperatures by 1-2C. The number of extreme weather events increased: cold prolonged winters, long rains in summers, cold weather returns in the early summer, early frosts in late summer - early autumn. Such conditions often

  3. Soil response to long-term projections of extreme temperature and precipitation in the southern La Plata Basin

    Science.gov (United States)

    Pántano, Vanesa C.; Penalba, Olga C.

    2017-12-01

    Projected changes were estimated considering the main variables which take part in soil-atmosphere interaction. The analysis was focused on the potential impact of these changes on soil hydric condition under extreme precipitation and evapotranspiration, using the combination of Global Climate Models (GCMs) and observational data. The region of study is the southern La Plata Basin that covers part of Argentine territory, where rainfed agriculture production is one of the most important economic activities. Monthly precipitation and maximum and minimum temperatures were used from high quality-controlled observed data from 46 meteorological stations and the ensemble of seven CMIP5 GCMs in two periods: 1970-2005 and 2065-2100. Projected changes in monthly effective temperature and precipitation were analysed. These changes were combined with observed series for each probabilistic interval. The result was used as input variables for the water balance model in order to obtain consequent soil hydric condition (deficit or excess). Effective temperature and precipitation are expected to increase according to the projections of GCMs, with few exceptions. The analysis revealed increase (decrease) in the prevalence of evapotranspiration over precipitation, during spring (winter). Projections for autumn months show precipitation higher than potential evapotranspiration more frequently. Under dry extremes, the analysis revealed higher projected deficit conditions, impacting on crop development. On the other hand, under wet extremes, excess would reach higher values only in particular months. During December, projected increase in temperatures reduces the impact of extreme high precipitation but favours deficit conditions, affecting flower-fructification stage of summer crops.

  4. Likelihood estimators for multivariate extremes

    KAUST Repository

    Huser, Raphaë l; Davison, Anthony C.; Genton, Marc G.

    2015-01-01

    The main approach to inference for multivariate extremes consists in approximating the joint upper tail of the observations by a parametric family arising in the limit for extreme events. The latter may be expressed in terms of componentwise maxima, high threshold exceedances or point processes, yielding different but related asymptotic characterizations and estimators. The present paper clarifies the connections between the main likelihood estimators, and assesses their practical performance. We investigate their ability to estimate the extremal dependence structure and to predict future extremes, using exact calculations and simulation, in the case of the logistic model.

  5. Likelihood estimators for multivariate extremes

    KAUST Repository

    Huser, Raphaël

    2015-11-17

    The main approach to inference for multivariate extremes consists in approximating the joint upper tail of the observations by a parametric family arising in the limit for extreme events. The latter may be expressed in terms of componentwise maxima, high threshold exceedances or point processes, yielding different but related asymptotic characterizations and estimators. The present paper clarifies the connections between the main likelihood estimators, and assesses their practical performance. We investigate their ability to estimate the extremal dependence structure and to predict future extremes, using exact calculations and simulation, in the case of the logistic model.

  6. Uncertainties in extreme precipitation under climate change conditions

    DEFF Research Database (Denmark)

    Sunyer Pinya, Maria Antonia

    of adaptation strategies, but these changes are subject to uncertainties. The focus of this PhD thesis is the quantification of uncertainties in changes in extreme precipitation. It addresses two of the main sources of uncertainty in climate change impact studies: regional climate models (RCMs) and statistical...... downscaling methods (SDMs). RCMs provide information on climate change at the regional scale. SDMs are used to bias-correct and downscale the outputs of the RCMs to the local scale of interest in adaptation strategies. In the first part of the study, a multi-model ensemble of RCMs from the European ENSEMBLES...... project was used to quantify the uncertainty in RCM projections over Denmark. Three aspects of the RCMs relevant for the uncertainty quantification were first identified and investigated. These are: the interdependency of the RCMs; the performance in current climate; and the change in the performance...

  7. Legacies from extreme drought increase ecosystem sensitivity to future extremes

    Science.gov (United States)

    Smith, M. D.; Knapp, A.; Hoover, D. L.; Avolio, M. L.; Felton, A. J.; Wilcox, K. R.

    2016-12-01

    Climate extremes, such as drought, are increasing in frequency and intensity, and the ecological consequences of these extreme events can be substantial and widespread. Although there is still much to be learned about how ecosystems will respond to an intensification of drought, even less is known about the factors that determine post-drought recovery of ecosystem function. Such knowledge is particularly important because post-drought recovery periods can be protracted depending on the extent to which key plant populations, community structure and biogeochemical processes are affected. These drought legacies may alter ecosystem function for many years post-drought and may impact future sensitivity to climate extremes. We experimentally imposed two extreme growing season droughts in a central US grassland to assess the impacts of repeated droughts on ecosystem resistance (response) and resilience (recovery). We found that this grassland was not resistant to the first extreme drought due to reduced productivity and differential sensitivity of the co-dominant C4 grass (Andropogon gerardii) and C3 forb (Solidago canadensis) species. This differential sensitivity led to a reordering of species abundances within the plant community. Yet, despite this large shift in plant community composition, which persisted post-drought, the grassland was highly resilient post-drought, due to increased abundance of the dominant C4 grass. Because of this shift to increased C4 grass dominance, we expected that previously-droughted grassland would be more resistant to a second extreme drought. However, contrary to these expectations, previously droughted grassland was more sensitive to drought than grassland that had not experienced drought. Thus, our result suggest that legacies of drought (shift in community composition) may increase ecosystem sensitivity to future extreme events.

  8. Enhancing the Extreme Climate Index (ECI) to monitor climate extremes for an index-based insurance scheme across Africa

    Science.gov (United States)

    Helmschrot, J.; Malherbe, J.; Chamunorwa, M.; Muthige, M.; Petitta, M.; Calmanti, S.; Cucchi, M.; Syroka, J.; Iyahen, E.; Engelbrecht, F.

    2017-12-01

    Climate services are a key component of National Adaptation Plan (NAP) processes, which require the analysis of current climate conditions, future climate change scenarios and the identification of adaptation strategies, including the capacity to finance and implement effective adaptation options. The Extreme Climate Facility (XCF) proposed by the African Risk Capacity (ARC) developed a climate index insurance scheme, which is based on the Extreme Climate Index (ECI): an objective, multi-hazard index capable of tracking changes in the frequency or magnitude of extreme weather events, thus indicating possible shifts to a new climate regime in various regions. The main hazards covered by ECI are extreme dry, wet and heat events, with the possibility of adding other region-specific risk events. The ECI is standardized across broad geographical regions, so that extreme events occurring under different climatic regimes in Africa can be compared. Initially developed by an Italian company specialized in Climate Services, research is now conducted at the CSIR and SASSCAL, to verify and further develop the ECI for application in southern African countries, through a project initiated by the World Food Programme (WFP) and ARC. The paper will present findings on the most appropriate definitions of extremely wet and dry conditions in Africa, in terms of their impact across a multitude of sub-regional climates of the African continent. Findings of a verification analysis of the ECI, as determined through vegetation monitoring data and the SASSCAL weather station network will be discussed. Changes in the ECI under climate change will subsequently be projected, using detailed regional projections generated by the CSIR and through the Coordinated Regional Downscaling Experiment (CORDEX). This work will be concluded by the development of a web-based climate service informing African Stakeholders on climate extremes.

  9. Projected changes of extreme weather events in the eastern United States based on a high resolution climate modeling system

    International Nuclear Information System (INIS)

    Gao, Y; Fu, J S; Drake, J B; Liu, Y; Lamarque, J-F

    2012-01-01

    This study is the first evaluation of dynamical downscaling using the Weather Research and Forecasting (WRF) Model on a 4 km × 4 km high resolution scale in the eastern US driven by the new Community Earth System Model version 1.0 (CESM v1.0). First we examined the global and regional climate model results, and corrected an inconsistency in skin temperature during the downscaling process by modifying the land/sea mask. In comparison with observations, WRF shows statistically significant improvement over CESM in reproducing extreme weather events, with improvement for heat wave frequency estimation as high as 98%. The fossil fuel intensive scenario Representative Concentration Pathway (RCP) 8.5 was used to study a possible future mid-century climate extreme in 2057–9. Both the heat waves and the extreme precipitation in 2057–9 are more severe than the present climate in the Eastern US. The Northeastern US shows large increases in both heat wave intensity (3.05 °C higher) and annual extreme precipitation (107.3 mm more per year). (letter)

  10. Ultra-high field upper extremity peripheral nerve and non-contrast enhanced vascular imaging.

    Directory of Open Access Journals (Sweden)

    Shailesh B Raval

    Full Text Available The purpose of this study was to explore the efficacy of Ultra-high field [UHF] 7 Tesla [T] MRI as compared to 3T MRI in non-contrast enhanced [nCE] imaging of structural anatomy in the elbow, forearm, and hand [upper extremity].A wide range of sequences including T1 weighted [T1] volumetric interpolate breath-hold exam [VIBE], T2 weighted [T2] double-echo steady state [DESS], susceptibility weighted imaging [SWI], time-of-flight [TOF], diffusion tensor imaging [DTI], and diffusion spectrum imaging [DSI] were optimized and incorporated with a radiofrequency [RF] coil system composed of a transverse electromagnetic [TEM] transmit coil combined with an 8-channel receive-only array for 7T upper extremity [UE] imaging. In addition, Siemens optimized protocol/sequences were used on a 3T scanner and the resulting images from T1 VIBE and T2 DESS were compared to that obtained at 7T qualitatively and quantitatively [SWI was only qualitatively compared]. DSI studio was utilized to identify nerves based on analysis of diffusion weighted derived fractional anisotropy images. Images of forearm vasculature were extracted using a paint grow manual segmentation method based on MIPAV [Medical Image Processing, Analysis, and Visualization].High resolution and high quality signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]-images of the hand, forearm, and elbow were acquired with nearly homogeneous 7T excitation. Measured [performed on the T1 VIBE and T2 DESS sequences] SNR and CNR values were almost doubled at 7T vs. 3T. Cartilage, synovial fluid and tendon structures could be seen with higher clarity in the 7T T1 and T2 weighted images. SWI allowed high resolution and better quality imaging of large and medium sized arteries and veins, capillary networks and arteriovenous anastomoses at 7T when compared to 3T. 7T diffusion weighted sequence [not performed at 3T] demonstrates that the forearm nerves are clearly delineated by fiber tractography. The

  11. Dynamics of indicators of a metabolic exchange and condition of blood circulation of the bottom extremities after traction extension at patients with lumbar and sacral dorsopathy

    Directory of Open Access Journals (Sweden)

    Kotenko К.V.

    2013-12-01

    Full Text Available Aim: to study influence of traction therapy in a pulse mode in a complex with electrotherapy on a condition of blood circulation of the bottom extremities and level of a metabolic exchange. Material and methods. There had been examined 120 patients with a lumbar and sacral dorsopathy aged from 22 to 69 years (middle age of 49,5 years with prescription of a disease from 1 to 5 years, among them men of 34,2%, women of 65,8%. Results. The analysis of effects of various medical methods on a condition of local blood circulation in the bottom extremities showed that the most expressed its compensation is noted at complex application of mechanical pulse traction influence and electrotherapy for patients with a dorsopathy of lumbar and sacral department of a backbone that is confirmed by restoration to normal values of all indicators rheovasogramm. Conclusion. High clinical results of application of the combined medical and rehabilitation complex are based on compensation of local blood circulation that is shown in elimination of deficiency of blood supply due to improvement of a tone of arterial vessels and elimination of venous stagnation, and also due to increase of linear speed of a blood-groove and development of collateral blood circulation. Application of electrical impulse and mechanical traction influences, more at their combination promotes fermentative activity of the systems responsible for a protein exchange that is important for prevention of degenerate and dystrophic process progressing.

  12. The Sphagnum microbiome supports bog ecosystem functioning under extreme conditions.

    Science.gov (United States)

    Bragina, Anastasia; Oberauner-Wappis, Lisa; Zachow, Christin; Halwachs, Bettina; Thallinger, Gerhard G; Müller, Henry; Berg, Gabriele

    2014-09-01

    Sphagnum-dominated bogs represent a unique yet widely distributed type of terrestrial ecosystem and strongly contribute to global biosphere functioning. Sphagnum is colonized by highly diverse microbial communities, but less is known about their function. We identified a high functional diversity within the Sphagnum microbiome applying an Illumina-based metagenomic approach followed by de novo assembly and MG-RAST annotation. An interenvironmental comparison revealed that the Sphagnum microbiome harbours specific genetic features that distinguish it significantly from microbiomes of higher plants and peat soils. The differential traits especially support ecosystem functioning by a symbiotic lifestyle under poikilohydric and ombrotrophic conditions. To realise a plasticity-stability balance, we found abundant subsystems responsible to cope with oxidative and drought stresses, to exchange (mobile) genetic elements, and genes that encode for resistance to detrimental environmental factors, repair and self-controlling mechanisms. Multiple microbe-microbe and plant-microbe interactions were also found to play a crucial role as indicated by diverse genes necessary for biofilm formation, interaction via quorum sensing and nutrient exchange. A high proportion of genes involved in nitrogen cycle and recycling of organic material supported the role of bacteria for nutrient supply. 16S rDNA analysis indicated a higher structural diversity than that which had been previously detected using PCR-dependent techniques. Altogether, the diverse Sphagnum microbiome has the ability to support the life of the host plant and the entire ecosystem under changing environmental conditions. Beyond this, the moss microbiome presents a promising bio-resource for environmental biotechnology - with respect to novel enzymes or stress-protecting bacteria. © 2014 John Wiley & Sons Ltd.

  13. Spin-resolved photoelectron spectroscopy using femtosecond extreme ultraviolet light pulses from high-order harmonic generation

    Energy Technology Data Exchange (ETDEWEB)

    Plötzing, M.; Adam, R., E-mail: r.adam@fz-juelich.de; Weier, C.; Plucinski, L.; Schneider, C. M. [Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-6), 52425 Jülich (Germany); Eich, S.; Emmerich, S.; Rollinger, M.; Aeschlimann, M. [University of Kaiserslautern and Research Center OPTIMAS, 67663 Kaiserslautern (Germany); Mathias, S. [Georg-August-Universität Göttingen, I. Physikalisches Institut, 37077 Göttingen (Germany)

    2016-04-15

    The fundamental mechanism responsible for optically induced magnetization dynamics in ferromagnetic thin films has been under intense debate since almost two decades. Currently, numerous competing theoretical models are in strong need for a decisive experimental confirmation such as monitoring the triggered changes in the spin-dependent band structure on ultrashort time scales. Our approach explores the possibility of observing femtosecond band structure dynamics by giving access to extended parts of the Brillouin zone in a simultaneously time-, energy- and spin-resolved photoemission experiment. For this purpose, our setup uses a state-of-the-art, highly efficient spin detector and ultrashort, extreme ultraviolet light pulses created by laser-based high-order harmonic generation. In this paper, we present the setup and first spin-resolved spectra obtained with our experiment within an acquisition time short enough to allow pump-probe studies. Further, we characterize the influence of the excitation with femtosecond extreme ultraviolet pulses by comparing the results with data acquired using a continuous wave light source with similar photon energy. In addition, changes in the spectra induced by vacuum space-charge effects due to both the extreme ultraviolet probe- and near-infrared pump-pulses are studied by analyzing the resulting spectral distortions. The combination of energy resolution and electron count rate achieved in our setup confirms its suitability for spin-resolved studies of the band structure on ultrashort time scales.

  14. Quantitative Assessment on Anthropogenic Contributions to the Rainfall Extremes Associated with Typhoon Morakot (2009)

    Science.gov (United States)

    Chen, C. T.; Lo, S. H.; Wang, C. C.; Tsuboki, K.

    2017-12-01

    More than 2000 mm rainfall occurred over southern Taiwan when a category 1 Typhoon Morakot pass through Taiwan in early August 2009. Entire village and hundred of people were buried by massive mudslides induced by record-breaking precipitation. Whether the past anthropogenic warming played a significant role in such extreme event remained very controversial. On one hand, people argue it's nearly impossible to attribute an individual extreme event to global warming. On the other hand, the increase of heavy rainfall is consistent with the expected effects of climate change on tropical cyclone. To diagnose possible anthropogenic contributions to the odds of such heavy rainfall associated with Typhoon Morakot, we adapt an existing probabilistic event attribution framework to simulate a `world that was' and compare it with an alternative condition, 'world that might have been' that removed the historical anthropogenic drivers of climate. One limitation for applying such approach to high-impact weather system is that it will require models capable of capturing the essential processes lead to the studied extremes. Using a cloud system resolving model that can properly simulate the complicated interactions between tropical cyclone, large-scale background, topography, we first perform the ensemble `world that was' simulations using high resolution ECMWF YOTC analysis. We then re-simulate, having adjusted the analysis to `world that might have been conditions' by removing the regional atmospheric and oceanic forcing due to human influences estimated from the CMIP5 model ensemble mean conditions between all forcing and natural forcing only historical runs. Thus our findings are highly conditional on the driving analysis and adjustments therein, but the setup allows us to elucidate possible contribution of anthropogenic forcing to changes in the likelihood of heavy rainfall associated Typhoon Morakot in early August 2009.

  15. High-energy roller injuries to the upper extremity.

    Science.gov (United States)

    Askins, G; Finley, R; Parenti, J; Bush, D; Brotman, S

    1986-12-01

    Eleven cases of high-energy industrial roller injuries treated between 1980 and 1984 were retrospectively reviewed. The dominant extremity was affected in nine. Six patients sustained fractures and/or dislocations, and three of these patients required fasciotomies for clinical signs of impending compartment syndromes. All fracture/dislocations, with the exception of a scapula fracture, anterior dislocation of a thumb interphalangeal joint, and a fractured coronoid process of the ulna, required open reduction with internal fixation. Three patients required split-thickness skin grafting for extensive skin degloving. Two patients required immediate amputation. Late sequelae included prolonged edema, nutritional depletion, neuroma formation of the superficial branch of the radial nerve, late carpal tunnel syndrome, and partial brachial plexus palsy. Industrial roller injuries continue to be an occupational hazard associated with more severe crushing trauma than the low-energy wringer washer injuries first described by MacCollum (11). Attention must be paid to the treatment of crushed skin, muscle, and nerves, fracture stabilization, nutritional support, and occupational therapy. Concurrent monitoring for signs of a developing compartment syndrome and complications of rhabdomyolysis is essential.

  16. Wind simulation for extreme and fatigue loads

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, M.; Larsen, G.C.; Mann, J.; Ott, S.; Hansen, K.S.; Pedersen, B.J.

    2004-01-01

    Measurements of atmospheric turbulence have been studied and found to deviate from a Gaussian process, in particular regarding the velocity increments over small time steps, where the tails of the pdf are exponential rather than Gaussian. Principles for extreme event counting and the occurrence of cascading events are presented. Empirical extreme statistics agree with Rices exceedence theory, when it is assumed that the velocity and its time derivative are independent. Prediction based on the assumption that the velocity is a Gaussian process underpredicts the rate of occurrence of extreme events by many orders of magnitude, mainly because the measured pdf is non-Gaussian. Methods for simulation of turbulent signals have been developed and their computational efficiency are considered. The methods are applicable for multiple processes with individual spectra and probability distributions. Non-Gaussian processes are simulated by the correlation-distortion method. Non-stationary processes are obtained by Bezier interpolation between a set of stationary simulations with identical random seeds. Simulation of systems with some signals available is enabled by conditional statistics. A versatile method for simulation of extreme events has been developed. This will generate gusts, velocity jumps, extreme velocity shears, and sudden changes of wind direction. Gusts may be prescribed with a specified ensemble average shape, and it is possible to detect the critical gust shape for a given construction. The problem is formulated as the variational problem of finding the most probable adjustment of a standard simulation of a stationary Gaussian process subject to relevant event conditions, which are formulated as linear combination of points in the realization. The method is generalized for multiple correlated series, multiple simultaneous conditions, and 3D fields of all velocity components. Generalization are presented for a single non-Gaussian process subject to relatively

  17. Manipulation of Samples at Extreme Temperatures for Fast in-situ Synchrotron Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Richard [Materials Development, Inc., Arlington Heights, IL (United States)

    2016-04-22

    An aerodynamic sample levitation system with laser beam heating was integrated with the APS beamlines 6 ID-D, 11 ID-C and 20 BM-B. The new capability enables in-situ measurements of structure and XANES at extreme temperatures (300-3500 °C) and in conditions that completely avoid contact with container surfaces. In addition to maintaining a high degree of sample purity, the use of aerodynamic levitation enables deep supercooling and greatly enhanced glass formation from a wide variety of melts and liquids. Development and integration of controlled extreme sample environments and new measurement techniques is an important aspect of beamline operations and user support. Processing and solidifying liquids is a critical value-adding step in manufacturing semiconductors, optical materials, metals and in the operation of many energy conversion devices. Understanding structural evolution is of fundamental importance in condensed materials, geology, and biology. The new capability provides unique possibilities for materials research and helps to develop and maintain a competitive materials manufacturing and energy utilization industry. Test samples were used to demonstrate key features of the capability including experiments on hot crystalline materials, liquids at temperatures from about 500 to 3500 °C. The use of controlled atmospheres using redox gas mixtures enabled in-situ changes in the oxidation states of cations in melts. Significant innovations in this work were: (i) Use of redox gas mixtures to adjust the oxidation state of cations in-situ (ii) Operation with a fully enclosed system suitable for work with nuclear fuel materials (iii) Making high quality high energy in-situ x-ray diffraction measurements (iv) Making high quality in-situ XANES measurements (v) Publishing high impact results (vi) Developing independent funding for the research on nuclear materials This SBIR project work led to a commercial instrument product for the niche market of processing and

  18. Liquid Water Restricts Habitability in Extreme Deserts

    Science.gov (United States)

    Cockell, Charles S.; Brown, Sarah; Landenmark, Hanna; Samuels, Toby; Siddall, Rebecca; Wadsworth, Jennifer

    2017-04-01

    Liquid water is a requirement for biochemistry, yet under some circumstances it is deleterious to life. Here, we show that liquid water reduces the upper temperature survival limit for two extremophilic photosynthetic microorganisms (Gloeocapsa and Chroococcidiopsis spp.) by greater than 40°C under hydrated conditions compared to desiccated conditions. Under hydrated conditions, thermal stress causes protein inactivation as shown by the fluorescein diacetate assay. The presence of water was also found to enhance the deleterious effects of freeze-thaw in Chroococcidiopsis sp. In the presence of water, short-wavelength UV radiation more effectively kills Gloeocapsa sp. colonies, which we hypothesize is caused by factors including the greater penetration of UV radiation into hydrated colonies compared to desiccated colonies. The data predict that deserts where maximum thermal stress or irradiation occurs in conjunction with the presence of liquid water may be less habitable to some organisms than more extreme arid deserts where organisms can dehydrate prior to being exposed to these extremes, thus minimizing thermal and radiation damage. Life in extreme deserts is poised between the deleterious effects of the presence and the lack of liquid water.

  19. Pyogenic Arthritis of the Ankle Joint Following a High-Voltage Electrical Burn in the Lower Extremity: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kuk Seon; Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Lee, Eil Seong; Min, Seon Jung; Han, You Mie [Dept. of Radiology, Hangang Scared Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of); Lee, Eil Seong [Dept.of Radiology, Gyeongju Hospital, Dongguk University College of Medicine, Gyeongju (Korea, Republic of)

    2011-04-15

    A high-voltage electrical burn caused extensive deep muscle injuries beneath a relatively small skin wound at the contact point. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, which can lead to major amputations or sepsis. The radiologic features of this rare, sometimes life-threatening injury have occasionally been described in the literature. However, to the best of our knowledge, there have been no reports on a case of pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity. We report a case of the pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity.

  20. XBeach-G: a tool for predicting gravel barrier response to extreme storm conditions

    Science.gov (United States)

    Masselink, Gerd; Poate, Tim; McCall, Robert; Roelvink, Dano; Russell, Paul; Davidson, Mark

    2014-05-01

    Gravel beaches protect low-lying back-barrier regions from flooding during storm events and their importance to society is widely acknowledged. Unfortunately, breaching and extensive storm damage has occurred at many gravel sites and this is likely to increase as a result of sea-level rise and enhanced storminess due to climate change. Limited scientific guidance is currently available to provide beach managers with operational management tools to predict the response of gravel beaches to storms. The New Understanding and Prediction of Storm Impacts on Gravel beaches (NUPSIG) project aims to improve our understanding of storm impacts on gravel coastal environments and to develop a predictive capability by modelling these impacts. The NUPSIG project uses a 5-pronged approach to address its aim: (1) analyse hydrodynamic data collected during a proto-type laboratory experiment on a gravel beach; (2) collect hydrodynamic field data on a gravel beach under a range of conditions, including storm waves with wave heights up to 3 m; (3) measure swash dynamics and beach response on 10 gravel beaches during extreme wave conditions with wave heights in excess of 3 m; (4) use the data collected under 1-3 to develop and validate a numerical model to model hydrodynamics and morphological response of gravel beaches under storm conditions; and (5) develop a tool for end-users, based on the model formulated under (4), for predicting storm response of gravel beaches and barriers. The aim of this presentation is to present the key results of the NUPSIG project and introduce the end-user tool for predicting storm response on gravel beaches. The model is based on the numerical model XBeach, and different forcing scenarios (wave and tides), barrier configurations (dimensions) and sediment characteristics are easily uploaded for model simulations using a Graphics User Interface (GUI). The model can be used to determine the vulnerability of gravel barriers to storm events, but can also be

  1. Thermal properties of bentonite under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Vasicek, R. [Czech Technical Univ., Centre of Experimental Geotechnics, Faculty of Civil Engineering, Prague (Czech Republic)

    2005-07-01

    Centre of Experimental Geotechnics (CEG) deals with the research of the behaviour of bentonite and clays. The measurement of thermal properties is not so frequent test in geotechnical laboratory but in relation to deep repository it is a part which should not be overlooked. The reason is the heat generated by canister with spent nuclear fuel and possible influence of the heat on the materials of the engineered barrier. In the initial stages following the burial of canister with the waste the barrier materials will be exposed to elevated temperature. According to existing information, these temperatures should not exceed 90 C. That heat can induce a creation of cracks and opening of joint between highly compacted blocks. It will predispose the bentonite barrier to penetration of water from surrounding towards to canister. Therefore easy removal of heat through the barrier is required. It is essential that the tests aimed at determining the real values of measured parameters are carried out in conditions identical with those anticipated in a future disposal system. These relatively complicated thermophysical tests are logical continuation of the simple ones, carried out under laboratory temperature and on not fully saturated samples without possibility to measure the swelling pressure. Thermophysical properties and swelling pressure are dominantly influenced by water content (which is influenced by temperature). Therefore is important to realize the tests under different moisture and thermal conditions. These tests are running at the APT-PO1 Analyser, designed to fulfill mentioned requirements - it allows measurement of thermal properties under temperature up to 200 C and swelling pressure up to 20 MPa. The device is capable to register the evolution of temperature, swelling and vapor pressure. The measurement of thermal conductivity and volume heat capacity is realized by the dynamic impulse method with point source of heat. Four types of tests are possible: at

  2. Extremely high efficiency phosphorescent organic light-emitting diodes with horizontal emitting dipoles

    Science.gov (United States)

    Kim, Kwon-Hyeon; Moon, Chang-Ki; Lee, Jeong-Hwan; Kim, Jang-Joo

    2014-10-01

    We present the factors influencing the orientation of the phosphorescent dyes in phosphorescent OLEDs. And, we report that an OLED containing a phosphorescent emitter with horizontally oriented dipoles in an exciplex-forming co-host that exhibits an extremely high EQE of 32.3% and power efficiency of 142 lm/W, the highest values ever reported in literature. Furthermore, we experimentally and theoretically correlated the EQE of OLEDs to the PL quantum yield and the horizontal dipole ratio of phosphorescent dyes using three different dyes.

  3. Influence of an extreme high water event on survival, reproduction, and distribution of snail kites in Florida, USA

    Science.gov (United States)

    Bennetts, R.E.; Kitchens, W.M.; Dreitz, V.J.

    2002-01-01

    Hydrology frequently has been reported as the environmental variable having the greatest influence on Florida snail kite (Rostrhamus sociabilis) populations. Although drought has received the most attention, high-water conditions also have been reported to affect kites. Years of high water generally have been reported to be favorable for nesting, although prolonged high water may be detrimental to sustaining suitable habitat. During 1994 and 1995, southern Florida experienced an extreme high water event. This event enabled us to compare survival, nesting success, number of young per successful nest, and spatial distribution of nesting before, during, and after the event. We found no evidence of an effect (either negative or positive) on survival of adult kites. In contrast, juvenile kites experienced the highest survival during the event, although our data suggest greater annual variability than can be explained by the event alone. We found no evidence of an effect of the high water event on nest success or number of young per successful nest. Nest success was highest during the event in the southern portion of the range but was quite similar to other years, both before and after the event. Our data do indicate a substantial shift in the spatial distribution of nesting birds. During the event, nesting activity shifted to higher elevations (i.e., shallower water) in the major nesting areas of the Everglades region. Nesting also occurred in Big Cypress National Preserve during the event, which is typically too dry to support nesting kites. Thus, our data indicate a potential short-term benefit of increased juvenile survival and an expansion of nesting habitat. However, the deterioration of habitat quality from prolonged high water precludes any recommendation for such conditions to be maintained for extended periods. ?? 2002, The Society of Wetland Scientists.

  4. Nitrogen accumulation and partitioning in a High Arctic tundra ecosystem from extreme atmospheric N deposition events

    Energy Technology Data Exchange (ETDEWEB)

    Choudhary, Sonal, E-mail: S.Choudhary@sheffield.ac.uk [Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN (United Kingdom); Management School, University of Sheffield, Conduit Road, Sheffield S10 1FL (United Kingdom); Blaud, Aimeric [Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN (United Kingdom); Osborn, A. Mark [Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN (United Kingdom); School of Applied Sciences, RMIT University, PO Box 71, Bundoora, VIC 3083 (Australia); Press, Malcolm C. [School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Manchester Metropolitan University, Manchester, M15 6BH (United Kingdom); Phoenix, Gareth K. [Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield S10 2TN (United Kingdom)

    2016-06-01

    Arctic ecosystems are threatened by pollution from recently detected extreme atmospheric nitrogen (N) deposition events in which up to 90% of the annual N deposition can occur in just a few days. We undertook the first assessment of the fate of N from extreme deposition in High Arctic tundra and are presenting the results from the whole ecosystem {sup 15}N labelling experiment. In 2010, we simulated N depositions at rates of 0, 0.04, 0.4 and 1.2 g N m{sup −2} yr{sup −1}, applied as {sup 15}NH{sub 4}{sup 15}NO{sub 3} in Svalbard (79{sup °}N), during the summer. Separate applications of {sup 15}NO{sub 3}{sup −} and {sup 15}NH{sub 4}{sup +} were also made to determine the importance of N form in their retention. More than 95% of the total {sup 15}N applied was recovered after one growing season (~ 90% after two), demonstrating a considerable capacity of Arctic tundra to retain N from these deposition events. Important sinks for the deposited N, regardless of its application rate or form, were non-vascular plants > vascular plants > organic soil > litter > mineral soil, suggesting that non-vascular plants could be the primary component of this ecosystem to undergo measurable changes due to N enrichment from extreme deposition events. Substantial retention of N by soil microbial biomass (70% and 39% of {sup 15}N in organic and mineral horizon, respectively) during the initial partitioning demonstrated their capacity to act as effective buffers for N leaching. Between the two N forms, vascular plants (Salix polaris) in particular showed difference in their N recovery, incorporating four times greater {sup 15}NO{sub 3}{sup −} than {sup 15}NH{sub 4}{sup +}, suggesting deposition rich in nitrate will impact them more. Overall, these findings show that despite the deposition rates being extreme in statistical terms, biologically they do not exceed the capacity of tundra to sequester pollutant N during the growing season. Therefore, current and future extreme events

  5. IOD and ENSO impacts on the extreme stream-flows of Citarum river in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Netrananda; Yamashiki, Yosuke; Takara, Kaoru [Kyoto University, Disaster Prevention Research Institute, Innovative Disaster Prevention Technology and Policy Research Laboratory, Gokasho, Uji City, Kyoto (Japan); Behera, Swadhin K. [JAMSTEC, Research Institute for Global Change, Yokohama, Kanagawa (Japan); JAMSTEC, Application Laboratory, Yokohama (Japan); Yamagata, Toshio [University of Tokyo, School of Science, Bunkyo-ku, Tokyo (Japan); JAMSTEC, Application Laboratory, Yokohama (Japan)

    2012-10-15

    Extreme stream-flow events of Citarum River are derived from the daily stream-flows at the Nanjung gauge station. Those events are identified based on their persistently extreme flows for 6 or more days during boreal fall when the seasonal mean stream-flow starts peaking-up from the lowest seasonal flows of June-August. Most of the extreme events of high-streamflows were related to La Nina conditions of tropical Pacific. A few of them were also associated with the negative phases of IOD and the newly identified El Nino Modoki. Unlike the cases of extreme high streamflows, extreme low streamflow events are seen to be associated with the positive IODs. Nevertheless, it was also found that the low-stream-flow events related to positive IOD events were also associated with El Nino events except for one independent event of 1977. Because the occurrence season coincides the peak season of IOD, not only the picked extreme events are seen to fall under the IOD seasons but also there exists a statistically significant correlation of 0.51 between the seasonal IOD index and the seasonal streamflows. There also exists a significant lag correlation when IOD of June-August season leads the streamflows of September-November. A significant but lower correlation coefficient (0.39) is also found between the seasonal streamflow and El Nino for September-November season only. (orig.)

  6. Evaluation of trends in high temperature extremes in north-western Europe in regional climate models

    International Nuclear Information System (INIS)

    Min, E; Hazeleger, W; Van Oldenborgh, G J; Sterl, A

    2013-01-01

    Projections of future changes in weather extremes on the regional and local scale depend on a realistic representation of trends in extremes in regional climate models (RCMs). We have tested this assumption for moderate high temperature extremes (the annual maximum of the daily maximum 2 m temperature, T ann.max ). Linear trends in T ann.max from historical runs of 14 RCMs driven by atmospheric reanalysis data are compared with trends in gridded station data. The ensemble of RCMs significantly underestimates the observed trends over most of the north-western European land surface. Individual models do not fare much better, with even the best performing models underestimating observed trends over large areas. We argue that the inability of RCMs to reproduce observed trends is probably not due to errors in large-scale circulation. There is also no significant correlation between the RCM T ann.max trends and trends in radiation or Bowen ratio. We conclude that care should be taken when using RCM data for adaptation decisions. (letter)

  7. Development of an Extreme Environment Materials Research Facility at Princeton

    International Nuclear Information System (INIS)

    Cohen, A.B.; Gentile, C.A.; Tully, C.G.; Austin, R.; Calaprice, F.; McDonald, K.; Ascione, G.; Baker, G.; Davidson, R.; Dudek, L.; Grisham, L.; Kugel, H.; Pagdon, K.; Stevenson, T.; Woolley, R.; Zwicker, A.

    2010-01-01

    The need for a fundamental understanding of material response to a neutron and/or high heat flux environment can yield development of improved materials and operations with existing materials. Such understanding has numerous applications in fields such as nuclear power (for the current fleet and future fission and fusion reactors), aerospace, and other research fields (e.g., high-intensity proton accelerator facilities for high energy physics research). A proposal has been advanced to develop a facility for testing various materials under extreme heat and neutron exposure conditions at Princeton. The Extreme Environment Materials Research Facility comprises an environmentally controlled chamber (48 m 3 ) capable of high vacuum conditions, with extreme flux beams and probe beams accessing a central, large volume target. The facility will have the capability to expose large surface areas (1 m 2 ) to 14 MeV neutrons at a fluence in excess of 10 13 n/s. Depending on the operating mode. Additionally beam line power on the order of 15-75 MW/m 2 for durations of 1-15 seconds are planned. The multi-second duration of exposure can be repeated every 2-10 minutes for periods of 10-12 hours. The facility will be housed in the test cell that held the Tokamak Fusion Test Reactor (TFTR), which has the desired radiation and safety controls as well as the necessary loading and assembly infrastructure. The facility will allow testing of various materials to their physical limit of thermal endurance and allow for exploring the interplay between radiation-induced embrittlement, swelling and deformation of materials, and the fatigue and fracturing that occur in response to thermal shocks. The combination of high neutron energies and intense fluences will enable accelerated time scale studies. The results will make contributions for refining predictive failure modes (modeling) in extreme environments, as well as providing a technical platform for the development of new alloys, new

  8. Lower extremity muscle activation during baseball pitching.

    Science.gov (United States)

    Campbell, Brian M; Stodden, David F; Nixon, Megan K

    2010-04-01

    The purpose of this study was to investigate muscle activation levels of select lower extremity muscles during the pitching motion. Bilateral surface electromyography data on 5 lower extremity muscles (biceps femoris, rectus femoris, gluteus maximus, vastus medialis, and gastrocnemius) were collected on 11 highly skilled baseball pitchers and compared with individual maximal voluntary isometric contraction (MVIC) data. The pitching motion was divided into 4 distinct phases: phase 1, initiation of pitching motion to maximum stride leg knee height; phase 2, maximum stride leg knee height to stride foot contact (SFC); phase 3, SFC to ball release; and phase 4, ball release to 0.5 seconds after ball release (follow-through). Results indicated that trail leg musculature elicited moderate to high activity levels during phases 2 and 3 (38-172% of MVIC). Muscle activity levels of the stride leg were moderate to high during phases 2-4 (23-170% of MVIC). These data indicate a high demand for lower extremity strength and endurance. Specifically, coaches should incorporate unilateral and bilateral lower extremity exercises for strength improvement or maintenance and to facilitate dynamic stabilization of the lower extremities during the pitching motion.

  9. Influence of a range of extreme environmental factors on tripartite lichen Peltigera aphthosa thallus viability

    Science.gov (United States)

    Irina, Insarova; Dyakov, Max; Ptushenko, Vasiliy; Shtaer, Oksana

    Lichens are symbiotic organisms consisting of at least two genetic different partners: a heterotrophic fungus (mycobiont) and a phototrophic alga or cyanobacterium (photobiont). Lichens are ubiquitous at global scale. These symbiotic organisms represent the dominant type of “vegetation” at 8 - 10% of land (Larson, 1987). Abiotic stress’ resistance is notable for lichens among all eukaryotes. Lichens are often called “extremophiles” for their ability to acclimate the most severe environmental conditions. These features allow regarding lichens as a group of organisms which is potentially able to keep viability under open space conditions and to survive within Mars-like atmosphere types. The research presented was carried out in the network of spacecraft Bion-1 experiments involving the investigation of physiological and ultrastructural changes in biological objects survivable under open space conditions. Similar researches were already conducted on bipartite lichen species. The most attention was paid to the influence of UV and other space radiation types on lichen viability in those works. Thus we have taken tripartite lichen Peltigera aphthosa as a main research object and temperature fluctuations from extremely high to extremely low values in accordance to solar and umbral orbit sides - for the main extreme environmental factors. These factors were the less studied in previous works. During the research the influence of incubation under anaerobic conditions, multi-time effects of high and low temperatures and their interchange on respiratory metabolism, photosynthetic apparatus condition and the ultrastructure of P. aphthosa thalli was assessed. The data obtained demonstrate that activity either mycobiont or photobiont in tripartite lichen Peltigera aphthosa keep near unchanged under influence of all stress factors explored on dry thalli.

  10. The effects of extracorporeal shockwave on acute high-energy long bone fractures of the lower extremity.

    Science.gov (United States)

    Wang, Ching-Jen; Liu, Hao-Chen; Fu, Te-Hu

    2007-02-01

    High-energy long bone fractures of the lower extremity are at risk of poor fracture healing and high rate of non-union. Extracorporeal shockwave was shown effective to heal non-union of long bone fracture. However, the effect of shockwave on acute fractures is unknown. The purpose of this study was to investigate the effects of shockwave on acute high-energy fractures of the lower extremity. Between January and October 2004, 56 patients with 59 acute high-energy fractures were enrolled in this study. Patients were randomly divided into two groups with 28 patients with 28 fractures in the study group and 28 patients with 31 fractures in the control group. Both groups showed similar age, gender, type of fracture and follow-up time. Patients in the study group received open reduction and internal fixation and shockwave treatment immediately after surgery on odd-numbered days of the week, whereas, patients in the control group received open reduction and internal fixation without shockwave treatment on even-numbered days of the week. Postoperative managements were similarly performed in both groups including crutch walking with non-weight bearing on the affected limb until fracture healing shown on radiographs. The evaluation parameters included clinical assessments of pain score and weight bearing status of the affected leg and serial radiographs at 3, 6 and 12 months. The primary end-point is the rate of non-union at 12 months, and the secondary end point is the rate of fracture healing at 3, 6 and 12 months. At 12 months, the rate of non-union was 11% for the study group versus 20% for the control group (P fracture healing was noted in the study group than the control group at 3, 6 and 12 months (P fracture healing and decreasing the rate of non-union in acute high-energy fractures of the lower extremity.

  11. Measurement Properties of the Lower Extremity Functional Scale: A Systematic Review.

    Science.gov (United States)

    Mehta, Saurabh P; Fulton, Allison; Quach, Cedric; Thistle, Megan; Toledo, Cesar; Evans, Neil A

    2016-03-01

    Systematic review of measurement properties. Many primary studies have examined the measurement properties, such as reliability, validity, and sensitivity to change, of the Lower Extremity Functional Scale (LEFS) in different clinical populations. A systematic review summarizing these properties for the LEFS may provide an important resource. To locate and synthesize evidence on the measurement properties of the LEFS and to discuss the clinical implications of the evidence. A literature search was conducted in 4 databases (PubMed, MEDLINE, Embase, and CINAHL), using predefined search terms. Two reviewers performed a critical appraisal of the included studies using a standardized assessment form. A total of 27 studies were included in the review, of which 18 achieved a very good to excellent methodological quality level. The LEFS scores demonstrated excellent test-retest reliability (intraclass correlation coefficients ranging between 0.85 and 0.99) and demonstrated the expected relationships with measures assessing similar constructs (Pearson correlation coefficient values of greater than 0.7). The responsiveness of the LEFS scores was excellent, as suggested by consistently high effect sizes (greater than 0.8) in patients with different lower extremity conditions. Minimal detectable change at the 90% confidence level (MDC90) for the LEFS scores varied between 8.1 and 15.3 across different reassessment intervals in a wide range of patient populations. The pooled estimate of the MDC90 was 6 points and the minimal clinically important difference was 9 points in patients with lower extremity musculoskeletal conditions, which are indicative of true change and clinically meaningful change, respectively. The results of this review support the reliability, validity, and responsiveness of the LEFS scores for assessing functional impairment in a wide array of patient groups with lower extremity musculoskeletal conditions.

  12. Prediction of extreme floods in the Central Andes by means of Complex Networks

    Science.gov (United States)

    Boers, Niklas; Bookhagen, Bodo; Barbosa, Henrique; Marwan, Norbert; Kurths, Jürgen; Marengo, Jose

    2014-05-01

    Based on a non-linear synchronisation measure and complex network theory, we present a novel framework for the prediction of extreme events of spatially embedded, interrelated time series. This method is general in the sense that it can be applied to any type of spatially sampled time series with significant interrelations, ranging from climate observables to biological or stock market data. In this presentation, we apply our method to extreme rainfall in South America and show how this leads to the prediction of more than 60% (90% during El Niño conditions) of extreme rainfall events in the eastern Central Andes of Bolivia and northern Argentina, with only 1% false alarms. From paleoclimatic to decadal time scales, the Central Andes continue to be subject to pronounced changes in climatic conditions. In particular, our and past work shows that frequency as well as magnitudes of extreme rainfall events have increased significantly during past decades, calling for a better understanding of the involved climatic mechanisms. Due to their large spatial extend and occurrence at high elevations, these extreme events often lead to severe floods and landslides with disastrous socioeconomic impacts. They regularly affect tens of thousands of people and produce estimated costs of the order of several hundred million USD. Alongside with the societal value of predicting natural hazards, our study provides insights into the responsible climatic features and suggests interactions between Rossby waves in polar regions and large scale (sub-)tropical moisture transport as a driver of subseasonal variability of the South American monsoon system. Predictable extreme events result from the propagation of extreme rainfall from the region of Buenos Aires towards the Central Andes given characteristic atmospheric conditions. Our results indicate that the role of frontal systems originating from Rossby waves in polar latitudes is much more dominant for controlling extreme rainfall in

  13. Study on extreme high temperature of cooling water in Chinese coastal nuclear power plant

    International Nuclear Information System (INIS)

    Yu Fan; Jiang Ziying

    2012-01-01

    In order to protect aquatic life from the harmful effects of thermal discharge, the appropriate water temperature limits or the scope of the mixing zone is a key issue in the regulatory control of the environmental impact of thermal discharge. Based on the sea surface temperature in the Chinese coastal waters, the extreme value of the seawater temperature change was analyzed by using the Gumbel model. The limit of the design temperature rise of cooling water in the outfall is 9 ℃, and the limit of the temperature rise of cooling water in the edge of the mixing zone is 4 ℃. The extreme high temperature of the cooling water in Chinese coastal nuclear power plant is 37 ℃ in the Bohai Sea, Yellow Sea, and is 40 ℃ in East China Sea, South China Sea. (authors)

  14. Gravo-Aeroelastic Scaling for Extreme-Scale Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Fingersh, Lee J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Loth, Eric [University of Virginia; Kaminski, Meghan [University of Virginia; Qin, Chao [University of Virginia; Griffith, D. Todd [Sandia National Laboratories

    2017-06-09

    A scaling methodology is described in the present paper for extreme-scale wind turbines (rated at 10 MW or more) that allow their sub-scale turbines to capture their key blade dynamics and aeroelastic deflections. For extreme-scale turbines, such deflections and dynamics can be substantial and are primarily driven by centrifugal, thrust and gravity forces as well as the net torque. Each of these are in turn a function of various wind conditions, including turbulence levels that cause shear, veer, and gust loads. The 13.2 MW rated SNL100-03 rotor design, having a blade length of 100-meters, is herein scaled to the CART3 wind turbine at NREL using 25% geometric scaling and blade mass and wind speed scaled by gravo-aeroelastic constraints. In order to mimic the ultralight structure on the advanced concept extreme-scale design the scaling results indicate that the gravo-aeroelastically scaled blades for the CART3 are be three times lighter and 25% longer than the current CART3 blades. A benefit of this scaling approach is that the scaled wind speeds needed for testing are reduced (in this case by a factor of two), allowing testing under extreme gust conditions to be much more easily achieved. Most importantly, this scaling approach can investigate extreme-scale concepts including dynamic behaviors and aeroelastic deflections (including flutter) at an extremely small fraction of the full-scale cost.

  15. Technology-derived storage solutions for stabilizing insulin in extreme weather conditions I: the ViViCap-1 device.

    Science.gov (United States)

    Pfützner, Andreas; Pesach, Gidi; Nagar, Ron

    2017-06-01

    Injectable life-saving drugs should not be exposed to temperatures 30°C/86°F. Frequently, weather conditions exceed these temperature thresholds in many countries. Insulin is to be kept at 4-8°C/~ 39-47°F until use and once opened, is supposed to be stable for up to 31 days at room temperature (exception: 42 days for insulin levemir). Extremely hot or cold external temperature can lead to insulin degradation in a very short time with loss of its glucose-lowering efficacy. Combined chemical and engineering solutions for heat protection are employed in ViViCap-1 for disposable insulin pens. The device works based on vacuum insulation and heat consumption by phase-change material. Laboratory studies with exposure of ViViCap-1 to hot outside conditions were performed to evaluate the device performance. ViViCap-1 keeps insulin at an internal temperature phase-change process and 'recharges' the device for further use. ViViCap-1 performed within its specifications. The small and convenient device maintains the efficacy and safety of using insulin even when carried under hot weather conditions.

  16. Effect of multiple-feedstock strategy on the economic and environmental performance of thermochemical ethanol production under extreme weather conditions

    International Nuclear Information System (INIS)

    Kou, Nannan; Zhao, Fu

    2011-01-01

    Current US transportation sector mainly relies on liquid hydrocarbons derived from petroleum and about 60% of the petroleum consumed is from areas where supply may be disturbed by regional instability. This has led to serious concerns on energy security and global warming. To address these issues, numerous alternative energy carriers have been proposed. Among them, second generation biofuel is one of the most promising technologies. Gasification-based thermochemical conversion will bring flexibility to both feedstock and production sides of a plant, thus presents an attractive technical route to address both the energy security and global warming concerns. In this paper, thermochemical ethanol production using multiple-feedstock (corn stover, municipal solid waste, and wood chips) is simulated using Aspen Plus and compared with the single-feedstock scenario, in terms of economic performances, life cycle greenhouse gas (GHG) emissions and survivability under extreme weather conditions. For a hypothetical facility in southwest Indiana it is found that multiple-feedstock strategy improves the net present value by 18% compared to single-feedstock strategy. This margin is increased to 57% when effects of extreme weather conditions on feedstock supply are considered. Moreover, multiple-feedstock fuel plant has no potential risk of bankruptcy during the payback period, while single-feedstock fuel plant has a 75% chance of bankruptcy. Although the multiple-feedstock strategy has 26% more GHG emission per liter of ethanol produced than the single-feedstock strategy, the trend is reversed if feedstock supply disruption is taken into account. Thus the idea of multiple-feedstock strategy is proposed to the future thermo chemical biofuel plants.

  17. Identifying Patterns in Extreme Precipitation Risk and the Related Impacts

    Science.gov (United States)

    Schroeer, K.; Tye, M. R.

    2017-12-01

    Extreme precipitation can harm human life and assets through flooding, hail, landslides, or debris flows. Flood risk assessments typically concentrate on river or mountain torrent channels, using water depth, flow velocity, and/or sediment deposition to quantify the risk. In addition, extreme events with high recurrence intervals are often the main focus. However, damages from short-term and localized convective showers often occur away from watercourses. Also, damages from more frequent small scale extremes, although usually less disastrous, can accumulate to considerable financial burdens. Extreme convective precipitation is expected to intensify in a warmer climate, and vulnerability patterns might change in tandem with changes in the character of precipitation and flood types. This has consequences for adaptation planners who want to establish effective protection measures and reduce the cost from natural hazards. Here we merge hydrological and exposure data to identify patterns of risk under varying synoptic conditions. Exposure is calculated from a database of 76k damage claims reported to the national disaster fund in 480 municipalities in south eastern Austria from 1990-2015. Hydrological data comprise sub-daily precipitation (59 gauges) and streamflow (62 gauges) observations. We use synoptic circulation types to identify typical precipitation patterns. They indicate the character of precipitation even if a gauge is not in close proximity, facilitating potential future research with regional climate model data. Results show that more claims are reported under synoptic conditions favouring convective precipitation (on average 1.5-3 times more than on other days). For agrarian municipalities, convective precipitation damages are among the costliest after long low-intensity precipitation events. In contrast, Alpine communities are particularly vulnerable to convective high-intensity rainfall. In addition to possible observational error, uncertainty is present

  18. Meteorological Drivers of Extreme Air Pollution Events

    Science.gov (United States)

    Horton, D. E.; Schnell, J.; Callahan, C. W.; Suo, Y.

    2017-12-01

    The accumulation of pollutants in the near-surface atmosphere has been shown to have deleterious consequences for public health, agricultural productivity, and economic vitality. Natural and anthropogenic emissions of ozone and particulate matter can accumulate to hazardous concentrations when atmospheric conditions are favorable, and can reach extreme levels when such conditions persist. Favorable atmospheric conditions for pollutant accumulation include optimal temperatures for photochemical reaction rates, circulation patterns conducive to pollutant advection, and a lack of ventilation, dispersion, and scavenging in the local environment. Given our changing climate system and the dual ingredients of poor air quality - pollutants and the atmospheric conditions favorable to their accumulation - it is important to characterize recent changes in favorable meteorological conditions, and quantify their potential contribution to recent extreme air pollution events. To facilitate our characterization, this study employs the recently updated Schnell et al (2015) 1°×1° gridded observed surface ozone and particulate matter datasets for the period of 1998 to 2015, in conjunction with reanalysis and climate model simulation data. We identify extreme air pollution episodes in the observational record and assess the meteorological factors of primary support at local and synoptic scales. We then assess (i) the contribution of observed meteorological trends (if extant) to the magnitude of the event, (ii) the return interval of the meteorological event in the observational record, simulated historical climate, and simulated pre-industrial climate, as well as (iii) the probability of the observed meteorological trend in historical and pre-industrial climates.

  19. Detection and Attribution of Climate Change : From global mean temperature change to climate extremes and high impact weather.

    CERN Multimedia

    CERN. Geneva

    2013-01-01

    This talk will describe how evidence has grown in recent years for a human influence on climate and explain how the Fifth Assessment Report of the Intergovernmental Panel on Climate Change concluded that it is extremely likely (>95% probability) that human influence on climate has been the dominant cause of the observed global-mean warming since the mid-20th century. The fingerprint of human activities has also been detected in warming of the ocean, in changes in the global water cycle, in reductions in snow and ice, and in changes in some climate extremes. The strengthening of evidence for the effects of human influence on climate extremes is in line with long-held basic understanding of the consequences of mean warming for temperature extremes and for atmospheric moisture. Despite such compelling evidence this does not mean that every instance of high impact weather can be attributed to anthropogenic climate change, because climate variability is often a major factor in many locations, especially for rain...

  20. Wave-induced extreme water levels in the Puerto Morelos fringing reef lagoon

    Directory of Open Access Journals (Sweden)

    A. Torres-Freyermuth

    2012-12-01

    Full Text Available Wave-induced extreme water levels in the Puerto Morelos fringing reef lagoon are investigated by means of a phase-resolving non-hydrostatic wave model (SWASH. This model solves the nonlinear shallow water equations including non-hydrostatic pressure. The one-dimensional version of the model is implemented in order to investigate wave transformation in fringing reefs. Firstly, the numerical model is validated with (i laboratory experiments conducted on a physical model (Demirbilek et al., 2007and (ii field observations (Coronado et al., 2007. Numerical results show good agreement with both experimental and field data. The comparison against the physical model results, for energetic wave conditions, indicates that high- and low-frequency wave transformation is well reproduced. Moreover, extreme water-level conditions measured during the passage of Hurricane Ivan in Puerto Morelos are also estimated by the numerical tool. Subsequently, the model is implemented at different along-reef locations in Puerto Morelos. Extreme water levels, wave-induced setup, and infragravity wave energy are estimated inside the reef lagoon for different storm wave conditions (Hs >2 m. The numerical results revealed a strong correlation between the offshore sea-swell wave energy and the setup. In contrast, infragravity waves are shown to be the result of a more complex pattern which heavily relies on the reef geometry. Indeed, the southern end of the reef lagoon provides evidence of resonance excitation, suggesting that the reef barrier may act as either a natural flood protection morphological feature, or as an inundation hazard enhancer depending on the incident wave conditions.

  1. Studies of nuclei under the extreme conditions of density, temperature, isospin asymmetry and the phase diagram of hadronic matter

    Energy Technology Data Exchange (ETDEWEB)

    Mekjian, Aram [Rutgers Univ., Piscataway, NJ (United States). Dept. of Physics and Astronomy

    2016-10-18

    The main emphasis of the entire project is on issues having to do with medium energy and ultra-relativistic energy and heavy ion collisions. A major goal of both theory and experiment is to study properties of hot dense nuclear matter under various extreme conditions and to map out the phase diagram in density or chemical potential and temperature. My studies in medium energy nuclear collisions focused on the liquid-gas phase transition and cluster yields from such transitions. Here I developed both the statistical model of nuclear multi-fragmentation and also a mean field theory.

  2. High-resolution projections of mean and extreme precipitations over China through PRECIS under RCPs

    Science.gov (United States)

    Zhu, Jinxin; Huang, Gordon; Wang, Xiuquan; Cheng, Guanhui; Wu, Yinghui

    2018-06-01

    The impact of global warming on the characteristics of mean and extreme precipitations over China is investigated by using the Providing REgional Climate Impacts for Studies (PRECIS) model. The PRECIS model was driven by the Hadley Centre Global Environment Model version 2 with Earth System components and coupling (HadGEM2-ES). The results of both models are analyzed in terms of mean precipitation and indices of precipitation extremes (R95p, R99p, SDII, WDF, and CWD) over China at the resolution of 25 km under the Representative Concentration Pathways 4.5 and 8.5 (RCP4.5 and RCP8.5) scenarios for the baseline period (1976-2005) and two future periods (2036-2065 and 2070-2099). With improved resolution, the PRECIS model is able to better represent the fine-scale physical process than HadGEM2-ES. It can provide reliable spatial patterns of precipitation and its related extremes with high correlations to observations. Moreover, there is a notable improvement in temporal patterns simulation through the PRECIS model. The PRECIS model better reproduces the regional annual cycle and frequencies of daily precipitation intensity than its driving GCM. Under RCP4.5 and RCP8.5, both the HadGEM2-ES and the precis project increasing annual precipitation over the entire country for two future periods. Precipitation increase in winter is greater than the increase in summer. The results suggest that increased radiative forcing from RCP4.5 to RCP8.5 would further intensify the magnitude of projected precipitation changes by both PRECIS and HadGEM2-ES. For example, some parts of south China with decreased precipitation under RCP4.5 would expect even less precipitation under RCP8.5; regions (northwest, northcentral and northeast China) with increased precipitation under RCP4.5 would expect more precipitation under RCP8.5. Apart from the projected increase in annual total precipitation, the results also suggest that there will be an increase in the days with precipitation higher than

  3. Extreme quantile estimation for dependent data with applications to finance

    OpenAIRE

    Drees, Holger

    2002-01-01

    The asymptotic normality of a class of estimators for extreme quantiles is established under mild structural conditions on the observed stationary \\beta-mixing time series. Consistent estimators of the asymptotic variance are introduced, which render possible the construction of asymptotic confidence intervals for the extreme quantiles. Moreover, it is shown that many well-known time series models satisfy our conditions. Then the theory is applied to a time series of returns of a stock in...

  4. Assessment of extreme value distributions for maximum temperature in the Mediterranean area

    Science.gov (United States)

    Beck, Alexander; Hertig, Elke; Jacobeit, Jucundus

    2015-04-01

    Extreme maximum temperatures highly affect the natural as well as the societal environment Heat stress has great effects on flora, fauna and humans and culminates in heat related morbidity and mortality. Agriculture and different industries are severely affected by extreme air temperatures. Even more under climate change conditions, it is necessary to detect potential hazards which arise from changes in the distributional parameters of extreme values, and this is especially relevant for the Mediterranean region which is characterized as a climate change hot spot. Therefore statistical approaches are developed to estimate these parameters with a focus on non-stationarities emerging in the relationship between regional climate variables and their large-scale predictors like sea level pressure, geopotential heights, atmospheric temperatures and relative humidity. Gridded maximum temperature data from the daily E-OBS dataset (Haylock et al., 2008) with a spatial resolution of 0.25° x 0.25° from January 1950 until December 2012 are the predictands for the present analyses. A s-mode principal component analysis (PCA) has been performed in order to reduce data dimension and to retain different regions of similar maximum temperature variability. The grid box with the highest PC-loading represents the corresponding principal component. A central part of the analyses is the model development for temperature extremes under the use of extreme value statistics. A combined model is derived consisting of a Generalized Pareto Distribution (GPD) model and a quantile regression (QR) model which determines the GPD location parameters. The QR model as well as the scale parameters of the GPD model are conditioned by various large-scale predictor variables. In order to account for potential non-stationarities in the predictors-temperature relationships, a special calibration and validation scheme is applied, respectively. Haylock, M. R., N. Hofstra, A. M. G. Klein Tank, E. J. Klok, P

  5. Extreme metabolic alkalosis in intensive care.

    Science.gov (United States)

    Tripathy, Swagata

    2009-10-01

    Metabolic alkalosis is a commonly seen imbalance in the intensive care unit (ICU). Extreme metabolic alkalemia, however, is less common. A pH greater than 7.65 may carry a high risk of mortality (up to 80%). We discuss the entity of life threatening metabolic alkalemia by means of two illustrative cases - both with a pH greater than 7.65 on presentation. The cause, modalities of managing and complications of this condition is discussed from the point of view of both the traditional method of Henderson and Hasselbalch and the mathematical model based on physiochemical model described by Stewart. Special mention to the pitfalls in managing patients of metabolic alkalosis with concomitant renal compromise is made.

  6. Models and Inference for Multivariate Spatial Extremes

    KAUST Repository

    Vettori, Sabrina

    2017-12-07

    The development of flexible and interpretable statistical methods is necessary in order to provide appropriate risk assessment measures for extreme events and natural disasters. In this thesis, we address this challenge by contributing to the developing research field of Extreme-Value Theory. We initially study the performance of existing parametric and non-parametric estimators of extremal dependence for multivariate maxima. As the dimensionality increases, non-parametric estimators are more flexible than parametric methods but present some loss in efficiency that we quantify under various scenarios. We introduce a statistical tool which imposes the required shape constraints on non-parametric estimators in high dimensions, significantly improving their performance. Furthermore, by embedding the tree-based max-stable nested logistic distribution in the Bayesian framework, we develop a statistical algorithm that identifies the most likely tree structures representing the data\\'s extremal dependence using the reversible jump Monte Carlo Markov Chain method. A mixture of these trees is then used for uncertainty assessment in prediction through Bayesian model averaging. The computational complexity of full likelihood inference is significantly decreased by deriving a recursive formula for the nested logistic model likelihood. The algorithm performance is verified through simulation experiments which also compare different likelihood procedures. Finally, we extend the nested logistic representation to the spatial framework in order to jointly model multivariate variables collected across a spatial region. This situation emerges often in environmental applications but is not often considered in the current literature. Simulation experiments show that the new class of multivariate max-stable processes is able to detect both the cross and inner spatial dependence of a number of extreme variables at a relatively low computational cost, thanks to its Bayesian hierarchical

  7. Simulation of the 23 July 2012 Extreme Space Weather Event: What if This Extremely Rare CME Was Earth Directed?

    Science.gov (United States)

    Ngwira, Chigomezyo M.; Pulkkinen, Antti; Mays, M. Leila; Kuznetsova, Maria M.; Galvin, A. B.; Simunac, Kristin; Baker, Daniel N.; Li, Xinlin; Zheng, Yihua; Glocer, Alex

    2013-01-01

    Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (approx. 1 AU) in about 19 h. Here we use the SpaceWeather Modeling Framework (SWMF) to perform a simulation of this rare CME.We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic field perturbations are used to compute the simulated induced geoelectric field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.

  8. Plant Responses to Extreme Climatic Events: A Field Test of Resilience Capacity at the Southern Range Edge

    Science.gov (United States)

    Herrero, Asier; Zamora, Regino

    2014-01-01

    The expected and already observed increment in frequency of extreme climatic events may result in severe vegetation shifts. However, stabilizing mechanisms promoting community resilience can buffer the lasting impact of extreme events. The present work analyzes the resilience of a Mediterranean mountain ecosystem after an extreme drought in 2005, examining shoot-growth and needle-length resistance and resilience of dominant tree and shrub species (Pinus sylvestris vs Juniperus communis, and P. nigra vs J. oxycedrus) in two contrasting altitudinal ranges. Recorded high vegetative-resilience values indicate great tolerance to extreme droughts for the dominant species of pine-juniper woodlands. Observed tolerance could act as a stabilizing mechanism in rear range edges, such as the Mediterranean basin, where extreme events are predicted to be more detrimental and recurrent. However, resistance and resilience components vary across species, sites, and ontogenetic states: adult Pinus showed higher growth resistance than did adult Juniperus; saplings displayed higher recovery rates than did conspecific adults; and P. nigra saplings displayed higher resilience than did P. sylvestris saplings where the two species coexist. P. nigra and J. oxycedrus saplings at high and low elevations, respectively, were the most resilient at all the locations studied. Under recurrent extreme droughts, these species-specific differences in resistance and resilience could promote changes in vegetation structure and composition, even in areas with high tolerance to dry conditions. PMID:24489971

  9. Plant responses to extreme climatic events: a field test of resilience capacity at the southern range edge.

    Directory of Open Access Journals (Sweden)

    Asier Herrero

    Full Text Available The expected and already observed increment in frequency of extreme climatic events may result in severe vegetation shifts. However, stabilizing mechanisms promoting community resilience can buffer the lasting impact of extreme events. The present work analyzes the resilience of a Mediterranean mountain ecosystem after an extreme drought in 2005, examining shoot-growth and needle-length resistance and resilience of dominant tree and shrub species (Pinus sylvestris vs Juniperus communis, and P. nigra vs J. oxycedrus in two contrasting altitudinal ranges. Recorded high vegetative-resilience values indicate great tolerance to extreme droughts for the dominant species of pine-juniper woodlands. Observed tolerance could act as a stabilizing mechanism in rear range edges, such as the Mediterranean basin, where extreme events are predicted to be more detrimental and recurrent. However, resistance and resilience components vary across species, sites, and ontogenetic states: adult Pinus showed higher growth resistance than did adult Juniperus; saplings displayed higher recovery rates than did conspecific adults; and P. nigra saplings displayed higher resilience than did P. sylvestris saplings where the two species coexist. P. nigra and J. oxycedrus saplings at high and low elevations, respectively, were the most resilient at all the locations studied. Under recurrent extreme droughts, these species-specific differences in resistance and resilience could promote changes in vegetation structure and composition, even in areas with high tolerance to dry conditions.

  10. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Y., E-mail: y.hirano@aist.go.jp, E-mail: hirano.yoichi@phys.cst.nihon-u.ac.jp [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); College of Science and Technologies, Nihon University, Chiyodaku, Tokyo 101-0897 (Japan); Kiyama, S.; Koguchi, H. [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Fujiwara, Y.; Sakakita, H. [Innovative Plasma Processing Group, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki 305-8577 (Japan)

    2015-11-15

    A high current density (≈3 mA/cm{sup 2}) hydrogen ion beam source operating in an extremely low-energy region (E{sub ib} ≈ 150–200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E{sub ib} is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  11. ACUTE EFFECTS OF STATIC STRETCHING, DYNAMIC EXERCISES, AND HIGH VOLUME UPPER EXTREMITY PLYOMETRIC ACTIVITY ON TENNIS SERVE PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Ertugrul Gelen

    2012-12-01

    Full Text Available The purpose of this study was to compare the acute effects of static stretching; dynamic exercises and high volume upper extremity plyometric activity on tennis serve performance. Twenty-six elite young tennis players (15.1 ± 4.2 years, 167.9 ± 5.8 cm and 61.6 ± 8.1 kg performed 4 different warm-up (WU routines in a random order on non-consecutive days. The WU methods consisted of traditional WU (jogging, rally and serve practice (TRAD; traditional WU and static stretching (TRSS; traditional WU and dynamic exercise (TRDE; and traditional WU and high volume upper extremity plyometric activity (TRPLYP. Following each WU session, subjects were tested on a tennis serve ball speed test. TRAD, TRSS, TRDE and TRPLYO were compared by repeated measurement analyses of variance and post-hoc comparisons. In this study a 1 to 3 percent increase in tennis serve ball speed was recorded in TRDE and TRPLYO when compared to TRAD (p 0.05. ICCs for ball speed showed strong reliability (0.82 to 0.93 for the ball speed measurements.The results of this study indicate that dynamic and high volume upper extremity plyometric WU activities are likely beneficial to serve speed of elite junior tennis players.

  12. Quantitative methods for stochastic high frequency spatio-temporal and non-linear analysis: Assessing health effects of exposure to extreme ambient temperature

    Science.gov (United States)

    Liss, Alexander

    Extreme weather events, such as heat waves and cold spells, cause substantial excess mortality and morbidity in the vulnerable elderly population, and cost billions of dollars. The accurate and reliable assessment of adverse effects of extreme weather events on human health is crucial for environmental scientists, economists, and public health officials to ensure proper protection of vulnerable populations and efficient allocation of scarce resources. However, the methodology for the analysis of large national databases is yet to be developed. The overarching objective of this dissertation is to examine the effect of extreme weather on the elderly population of the Conterminous US (ConUS) with respect to seasonality in temperature in different climatic regions by utilizing heterogeneous high frequency and spatio-temporal resolution data. To achieve these goals the author: 1) incorporated dissimilar stochastic high frequency big data streams and distinct data types into the integrated data base for use in analytical and decision support frameworks; 2) created an automated climate regionalization system based on remote sensing and machine learning to define climate regions for the Conterminous US; 3) systematically surveyed the current state of the art and identified existing gaps in the scientific knowledge; 4) assessed the dose-response relationship of exposure to temperature extremes on human health in relatively homogeneous climate regions using different statistical models, such as parametric and non-parametric, contemporaneous and asynchronous, applied to the same data; 5) assessed seasonal peak timing and synchronization delay of the exposure and the disease within the framework of contemporaneous high frequency harmonic time series analysis and modification of the effect by the regional climate; 6) modeled using hyperbolic functional form non-linear properties of the effect of exposure to extreme temperature on human health. The proposed climate

  13. Improved Survival With Radiation Therapy in High-Grade Soft Tissue Sarcomas of the Extremities: A SEER Analysis

    International Nuclear Information System (INIS)

    Koshy, Matthew; Rich, Shayna E.; Mohiuddin, Majid M.

    2010-01-01

    Purpose: The benefit of radiation therapy in extremity soft tissue sarcomas remains controversial. The purpose of this study was to determine the effect of radiation therapy on overall survival among patients with primary soft tissue sarcomas of the extremity who underwent limb-sparing surgery. Methods and Materials: A retrospective study from the Surveillance, Epidemiology, and End Results (SEER) database that included data from January 1, 1988, to December 31, 2005. A total of 6,960 patients constituted the study population. Overall survival curves were constructed using the Kaplan-Meir method and for patients with low- and high-grade tumors. Hazard ratios were calculated based on multivariable Cox proportional hazards models. Results: Of the cohort, 47% received radiation therapy. There was no significant difference in overall survival among patients with low-grade tumors by radiation therapy. In high-grade tumors, the 3-year overall survival was 73% in patients who received radiation therapy vs. 63% for those who did not receive radiation therapy (p < 0.001). On multivariate analysis, patients with high-grade tumors who received radiation therapy had an improved overall survival (hazard ratio 0.67, 95% confidence interval 0.57-0.79). In patients receiving radiation therapy, 13.5% received it in a neoadjuvant setting. The incidence of patients receiving neoadjuvant radiation did not change significantly between 1988 and 2005. Conclusions: To our knowledge, this is the largest population-based study reported in patients undergoing limb-sparing surgery for soft tissue sarcomas of the extremities. It reports that radiation was associated with improved survival in patients with high-grade tumors.

  14. Gene expression profiles in testis of pigs with extreme high and low levels of androstenone

    Directory of Open Access Journals (Sweden)

    Bendixen Christian

    2007-11-01

    Full Text Available Abstract Background: Boar taint is a major obstacle when using uncastrated male pigs for swine production. One of the main compounds causing this taint is androstenone, a pheromone produced in porcine testis. Here we use microarrays to study the expression of thousands of genes simultaneously in testis of high and low androstenone boars. The study allows identification of genes and pathways associated with elevated androstenone levels, which is essential for recognising potential molecular markers for breeding purposes. Results: Testicular tissue was collected from 60 boars, 30 with extreme high and 30 with extreme low levels of androstenone, from each of the two breeds Duroc and Norwegian Landrace. The samples were hybridised to porcine arrays containing 26,877 cDNA clones, detecting 563 and 160 genes that were differentially expressed (p Conclusion: This study contributes to the understanding of the complex genetic system controlling and responding to androstenone levels in pig testis. The identification of new pathways and genes involved in the biosynthesis and metabolism of androstenone is an important first step towards finding molecular markers to reduce boar taint.

  15. Are recent severe floods in Xiang River basin of China linked with the increase extreme precipitation?

    Science.gov (United States)

    Cheng, L.; Du, J.

    2015-12-01

    The Xiang River, a main tributary of the Yangtze River, is subjected to high floods frequently in recent twenty years. Climate change, including abrupt shifts and fluctuations in precipitation is an important factor influencing hydrological extreme conditions. In addition, human activities are widely recognized as another reasons leading to high flood risk. With the effects of climate change and human interventions on hydrological cycle, there are several questions that need to be addressed. Are floods in the Xiang River basin getting worse? Whether the extreme streamflow shows an increasing tendency? If so, is it because the extreme rainfall events have predominant effect on floods? To answer these questions, the article detected existing trends in extreme precipitation and discharge using Mann-Kendall test. Continuous wavelet transform method was employed to identify the consistency of changes in extreme precipitation and discharge. The Pearson correlation analysis was applied to investigate how much degree of variations in extreme discharge can be explained by climate change. The results indicate that slightly upward trends can be detected in both extreme rainfalls and discharge in the upper region of Xiang River basin. For the most area of middle and lower river basin, the extreme rainfalls show significant positive trends, but the extreme discharge displays slightly upward trends with no significance at 90% confidence level. Wavelet transform analysis results illustrate that highly similar patterns of signal changes can be seen between extreme precipitation and discharge in upper section of the basin, while the changes in extreme precipitation for the middle and lower reaches do not always coincide with the extreme streamflow. The correlation coefficients of the wavelet transforms for the precipitation and discharge signals in most area of the basin pass the significance test. The conclusion may be drawn that floods in recent years are not getting worse in

  16. Mitigation of houses with extremely high indoor radon concentrations

    International Nuclear Information System (INIS)

    Jiranek, M.; Neznal, M.

    2006-01-01

    Full text of publication follows: The paper reports on the experience of the Czech Technical University in dealing with mitigation of houses in which unusually high indoor radon concentrations were found. The whole process of remediation is illustrated by example of an old single-family house that was built in the area formed by highly permeable soils with high radon content in the soil air. T he house has a small cellar located under 1/5 of the ground floor area. Two types of floors, i.e. timber floors and cracked concrete slabs were found in the house. As a result of extremely high radon concentration in the sub-floor region (up to 600 kBq/m 3 ) and leaky structures in contact with soil, radon concentrations around 100 kBq/m 3 in the cellar and up to 60 kBq/m 3 in the living rooms on the ground floor were measured prior to mitigation. Mitigation measures that were carried out in the house consist of reconstruction of timber floors and installation of active soil depressurization. Timber floors were replaced with concrete slab fitted with damp proof membrane, thermal insulation and floor covering. The soil depressurization system was made up of two sections. The first section is composed of the network of perforated pipes inserted in the drainage layer placed under the new floors and four perforated tubes drilled under the existing floors. The soil air from this section is extracted by means of a roof fan installed at the top of the vertical exhaust pipe running inside the living space and terminating above the roof. The second section was designed to withdraw by means of a small fan radon-laden air from the filling in the floor above the cellar and from perforated tubes drilled into the sub-floor region under the rooms adjacent to the cellar. It serves also for the active ventilation of the cellar. Pressure, temperature and radon concentration sensors were installed into the drainage layer during the reconstruction of floors to record variations in these

  17. TYPHOID FEVER WITH FATAL OUTCOME IN PEOPLE WITH SEVERE TROPHOLOGICAL FAILURE IN EXTREME CONDITIONS

    Directory of Open Access Journals (Sweden)

    Yu. I. Lyashenko

    2017-01-01

    Full Text Available For purpose of clinical and morphological characterization of typhoid fever with fatal outcome was perform analysis of medical documentation as well as postmortem studies of internal tissues in 36men aged 21 to 34 years with severe body weight loss and in the conditions of combat stress in period from 1983 to 1985. The results of the study find a number of clinical and pathomorphological features of typhoid fever in patients with body weight deficiency that were in extreme conditions. Focal changes of the central nervous system were detected. The defeat of the respiratory system was characterized from the first days of the disease by bronchitis, and in the subsequent development of pneumonia, plevritis and empyema of the pleura. Majority of patients had symptoms of cardiovascular and renal failure. In died in the first week of the disease and in 2/3 parts – in a later period were combined with the symptoms of infectious-toxic encephalopathy and severe acute respiratory failure. All died had postmortem dystrophic changes of cardiomyocytes, and in patients had fatal outcome in 2–5 weeks – also focal or diffuse myocarditis. In a third of the patients who died, the disease was complicated by intestinal perforations. In a number of cases, peritonitis was a consequence of necrosis of mesenteric lymph nodes. In all patients with a fatal outcome, hemorrhagic (thrombohemorrhagic syndrome was diagnosed. A significant proportion of patients posthumously detected signs of sepsis and other complications, many of which could be the cause of death.

  18. Meeting the challenge of extremely corrosive service: A primer on clad oilfield equipment

    International Nuclear Information System (INIS)

    Pendley, M.R.

    1993-01-01

    Extremely corrosive environments, such as those often encountered in deep, hot, sour oil and gas wells, are usually characterized by the presence of hydrogen sulfide (H 2 S), carbon dioxide (CO 2 ), chlorides, and other corrosive species coupled with high temperatures (> 400 F/204 C) and high pressures (up to 20,000 psi/138 MPa). Most low alloy and stainless steel materials are not suitable for such environments. Extremely corrosive service conditions dictate the use of a corrosion-resistant alloy (CRA) in areas which are exposed to the hostile environment. However, it is often cost-prohibitive to make an entire component out of CRA material. An alternative strategy is to use a low alloy steel for the bulk of the component and clad critical surfaces with a corrosion-resistant material. Clad equipment can provide excellent corrosion resistance in hostile environments at a fraction of the cost of 100% CRA components. This paper will detail the problems posed by extremely corrosive environments and discuss how clad equipment provides a cost-effective solution

  19. IOD and ENSO impacts on the extreme stream-flows of Citarum river in Indonesia

    Science.gov (United States)

    Sahu, Netrananda; Behera, Swadhin K.; Yamashiki, Yosuke; Takara, Kaoru; Yamagata, Toshio

    2012-10-01

    Extreme stream-flow events of Citarum River are derived from the daily stream-flows at the Nanjung gauge station. Those events are identified based on their persistently extreme flows for 6 or more days during boreal fall when the seasonal mean stream-flow starts peaking-up from the lowest seasonal flows of June-August. Most of the extreme events of high-streamflows were related to La Niña conditions of tropical Pacific. A few of them were also associated with the negative phases of IOD and the newly identified El Niño Modoki. Unlike the cases of extreme high streamflows, extreme low streamflow events are seen to be associated with the positive IODs. Nevertheless, it was also found that the low-stream-flow events related to positive IOD events were also associated with El Niño events except for one independent event of 1977. Because the occurrence season coincides the peak season of IOD, not only the picked extreme events are seen to fall under the IOD seasons but also there exists a statistically significant correlation of 0.51 between the seasonal IOD index and the seasonal streamflows. There also exists a significant lag correlation when IOD of June-August season leads the streamflows of September-November. A significant but lower correlation coefficient (0.39) is also found between the seasonal streamflow and El Niño for September-November season only.

  20. THE HIGH-RESOLUTION EXTREME-ULTRAVIOLET SPECTRUM OF N{sub 2} BY ELECTRON IMPACT

    Energy Technology Data Exchange (ETDEWEB)

    Heays, A. N. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Ajello, J. M.; Aguilar, A. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Lewis, B. R.; Gibson, S. T., E-mail: heays@strw.leidenuniv.nl [Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)

    2014-04-01

    We have analyzed high-resolution (FWHM = 0.2 Å) extreme-ultraviolet (EUV, 800-1350 Å) laboratory emission spectra of molecular nitrogen excited by an electron impact at 20 and 100 eV under (mostly) optically thin, single-scattering experimental conditions. A total of 491 emission features were observed from N{sub 2} electronic-vibrational transitions and atomic N I and N II multiplets and their emission cross sections were measured. Molecular emission was observed at vibrationally excited ground-state levels as high as v'' = 17, from the a {sup 1}Π {sub g} , b {sup 1}Π {sub u} , and b'{sup 1}Σ {sub u} {sup +} excited valence states and the Rydberg series c'{sub n} {sub +1} {sup 1}Σ {sub u} {sup +}, c{sub n} {sup 1}Π {sub u} , and o{sub n} {sup 1}Π {sub u} for n between 3 and 9. The frequently blended molecular emission bands were disentangled with the aid of a sophisticated and predictive quantum-mechanical model of excited states that includes the strong coupling between valence and Rydberg electronic states and the effects of predissociation. Improved model parameters describing electronic transition moments were obtained from the experiment and allowed for a reliable prediction of the vibrationally summed electronic emission cross section, including an extrapolation to unobserved emission bands and those that are optically thick in the experimental spectra. Vibrationally dependent electronic excitation functions were inferred from a comparison of emission features following 20 and 100 eV electron-impact collisional excitation. The electron-impact-induced fluorescence measurements are compared with Cassini Ultraviolet Imaging Spectrograph observations of emissions from Titan's upper atmosphere.

  1. Nuclear power plant Olkiluoto 3. Containment leakage test under extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Fleckenstein, Tobias [TUEV SUED Industrie Service GmbH, Munich (Germany). Measaruement Technology Dept.

    2015-01-15

    Modern nuclear power plants place high demands on the design and execution of safety checks. TUEV SUED supported the containment leakage test for the largest- capacity third generation nuclear power plant in the world - Olkiluoto 3 in Finland. The experts successfully met the challenges presented by exceptional parameters of the project. The containment of Olkiluoto 3 is unique in that the vessel's volume is 80,000 m{sup 3} while measurements were carried out over a period of ten days. To execute the test, 75 temperature and 15 humidity sensors had to be installed and correctly interlinked by more than ten kilometres of cable. These instruments also needed to withstand an absolute pressure of 6 bar, ambient temperatures of 30 C and high levels of humidity. These conditions required comprehensive preparation and a high amount of qualification tests. Parts of the qualifications were carried out at the autoclave system of the Technical University in Munich, Germany, where the project test conditions could be simulated. The software required to determine the tests was developed by TUEV SUED and verified by German's national accreditation body DAkkS under ISO 17025. TUEV SUED enabled the test schedule to continue without delay by analysing all recorded data continuously on site, including pressure, temperature, humidity and leakage mass flow curves. With the comprehensive preparation, data acquisition system recording measurements continuously and the on-time result calculation, all components of the leak-tightness assessment were successfully completed in accordance with requirements.

  2. Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic

    International Nuclear Information System (INIS)

    Hansen, Brage B; Isaksen, Ketil; Benestad, Rasmus E; Kohler, Jack; Pedersen, Åshild Ø; Loe, Leif E; Coulson, Stephen J; Larsen, Jan Otto; Varpe, Øystein

    2014-01-01

    One predicted consequence of global warming is an increased frequency of extreme weather events, such as heat waves, droughts, or heavy rainfalls. In parts of the Arctic, extreme warm spells and heavy rain-on-snow (ROS) events in winter are already more frequent. How these weather events impact snow-pack and permafrost characteristics is rarely documented empirically, and the implications for wildlife and society are hence far from understood. Here we characterize and document the effects of an extreme warm spell and ROS event that occurred in High Arctic Svalbard in January–February 2012, during the polar night. In this normally cold semi-desert environment, we recorded above-zero temperatures (up to 7 °C) across the entire archipelago and record-breaking precipitation, with up to 98 mm rainfall in one day (return period of >500 years prior to this event) and 272 mm over the two-week long warm spell. These precipitation amounts are equivalent to 25 and 70% respectively of the mean annual total precipitation. The extreme event caused significant increase in permafrost temperatures down to at least 5 m depth, induced slush avalanches with resultant damage to infrastructure, and left a significant ground-ice cover (∼5–20 cm thick basal ice). The ground-ice not only affected inhabitants by closing roads and airports as well as reducing mobility and thereby tourism income, but it also led to high starvation-induced mortality in all monitored populations of the wild reindeer by blocking access to the winter food source. Based on empirical-statistical downscaling of global climate models run under the moderate RCP4.5 emission scenario, we predict strong future warming with average mid-winter temperatures even approaching 0 °C, suggesting increased frequency of ROS. This will have far-reaching implications for Arctic ecosystems and societies through the changes in snow-pack and permafrost properties. (letter)

  3. Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic

    Science.gov (United States)

    Hansen, Brage B.; Isaksen, Ketil; Benestad, Rasmus E.; Kohler, Jack; Pedersen, Åshild Ø.; Loe, Leif E.; Coulson, Stephen J.; Larsen, Jan Otto; Varpe, Øystein

    2014-11-01

    One predicted consequence of global warming is an increased frequency of extreme weather events, such as heat waves, droughts, or heavy rainfalls. In parts of the Arctic, extreme warm spells and heavy rain-on-snow (ROS) events in winter are already more frequent. How these weather events impact snow-pack and permafrost characteristics is rarely documented empirically, and the implications for wildlife and society are hence far from understood. Here we characterize and document the effects of an extreme warm spell and ROS event that occurred in High Arctic Svalbard in January-February 2012, during the polar night. In this normally cold semi-desert environment, we recorded above-zero temperatures (up to 7 °C) across the entire archipelago and record-breaking precipitation, with up to 98 mm rainfall in one day (return period of >500 years prior to this event) and 272 mm over the two-week long warm spell. These precipitation amounts are equivalent to 25 and 70% respectively of the mean annual total precipitation. The extreme event caused significant increase in permafrost temperatures down to at least 5 m depth, induced slush avalanches with resultant damage to infrastructure, and left a significant ground-ice cover (˜5-20 cm thick basal ice). The ground-ice not only affected inhabitants by closing roads and airports as well as reducing mobility and thereby tourism income, but it also led to high starvation-induced mortality in all monitored populations of the wild reindeer by blocking access to the winter food source. Based on empirical-statistical downscaling of global climate models run under the moderate RCP4.5 emission scenario, we predict strong future warming with average mid-winter temperatures even approaching 0 °C, suggesting increased frequency of ROS. This will have far-reaching implications for Arctic ecosystems and societies through the changes in snow-pack and permafrost properties.

  4. Probing the origin of cosmic-rays with extremely high energy neutrinos using the IceCube Observatory

    DEFF Research Database (Denmark)

    Aartsen, M.G.; Abbasi, R.; Ackermann, M.

    2013-01-01

    originate from cosmogenic neutrinos produced in the interactions of ultrahigh energy cosmic rays with ambient photons while propagating through intergalactic space. Exploiting IceCube’s large exposure for extremely high energy neutrinos and the lack of observed events above 100 PeV, we can rule out...

  5. Prospect for extreme field science

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, T. [Ludwig Maximilian Univ. and Max Planck Institute for Quantum Optics, Garching (Germany); Japan Atomic Energy Agency, Kyoto and KEK, Tsukuba (Japan)

    2009-11-15

    The kind of laser extreme light infrastructure (ELI) provides will usher in a class of experiments we have only dreamed of for years. The characteristics that ELI brings in include: the highest intensity ever, large fluence, and relatively high repetition rate. A personal view of the author on the prospect of harnessing this unprecedented opportunity for advancing science of extreme fields is presented. The first characteristic of ELI, its intensity, will allow us to access, as many have stressed already, extreme fields that hover around the Schwinger field or at the very least the neighboring fields in which vacuum begins to behave as a nonlinear medium. In this sense, we are seriously probing the 'material' property of vacuum and thus the property that theory of relativity itself described and will entail. We will probe both special theory and general theory of relativity in regimes that have been never tested so far. We may see a glimpse into the reach of relativity or even its breakdown in some extreme regimes. We will learn Einstein and may even go beyond Einstein, if our journey is led. Laser-driven acceleration both by the laser field itself and by the wakefield that is triggered in a plasma is huge. Energies, if not luminosity, we can access, may be unprecedented going far beyond TeV. The nice thing about ELI is that it has relatively high repetition rate and average fluence as compared with other extreme lasers. This high fluence can be a key element that leads to applications to high energy physics, such as gamma-gamma collider driver experiment, and some gamma ray experiments that may be relevant in the frontier of photo-nuclear physics, and atomic energy applications. Needless to say, high fluence is one of most important features that industrial and medical applications may need. If we are lucky, we may see a door opens at the frontier of novel physics that may not be available by any other means. (authors)

  6. Halophilic archaea on Earth and in space: growth and survival under extreme conditions.

    Science.gov (United States)

    Oren, Aharon

    2014-12-13

    Salts are abundant on Mars, and any liquid water that is present or may have been present on the planet is expected to be hypersaline. Halophilic archaea (family Halobacteriaceae) are the microorganisms best adapted to life at extremes of salinity on Earth. This paper reviews the properties of the Halobacteriaceae that may make the group good candidates for life also on Mars. Many species resist high UV and gamma radiation levels; one species has survived exposure to vacuum and radiation during a space flight; and there is at least one psychrotolerant species. Halophilic archaea may survive for millions of years within brine inclusions in salt crystals. Many species have different modes of anaerobic metabolism, and some can use light as an energy source using the light-driven proton pump bacteriorhodopsin. They are also highly tolerant to perchlorate, recently shown to be present in Martian soils, and some species can even use perchlorate as an electron acceptor to support anaerobic growth. The presence of characteristic carotenoid pigments (α-bacterioruberin and derivatives) makes the Halobacteriaceae easy to identify by Raman spectroscopy. Thus, if present on Mars, such organisms may be detected by Raman instrumentation planned to explore Mars during the upcoming ExoMars mission. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Extreme ground motions and Yucca Mountain

    Science.gov (United States)

    Hanks, Thomas C.; Abrahamson, Norman A.; Baker, Jack W.; Boore, David M.; Board, Mark; Brune, James N.; Cornell, C. Allin; Whitney, John W.

    2013-01-01

    Yucca Mountain is the designated site of the underground repository for the United States' high-level radioactive waste (HLW), consisting of commercial and military spent nuclear fuel, HLW derived from reprocessing of uranium and plutonium, surplus plutonium, and other nuclear-weapons materials. Yucca Mountain straddles the western boundary of the Nevada Test Site, where the United States has tested nuclear devices since the 1950s, and is situated in an arid, remote, and thinly populated region of Nevada, ~100 miles northwest of Las Vegas. Yucca Mountain was originally considered as a potential underground repository of HLW because of its thick units of unsaturated rocks, with the repository horizon being not only ~300 m above the water table but also ~300 m below the Yucca Mountain crest. The fundamental rationale for a geologic (underground) repository for HLW is to securely isolate these materials from the environment and its inhabitants to the greatest extent possible and for very long periods of time. Given the present climate conditions and what is known about the current hydrologic system and conditions around and in the mountain itself, one would anticipate that the rates of infiltration, corrosion, and transport would be very low—except for the possibility that repository integrity might be compromised by low-probability disruptive events, which include earthquakes, strong ground motion, and (or) a repository-piercing volcanic intrusion/eruption. Extreme ground motions (ExGM), as we use the phrase in this report, refer to the extremely large amplitudes of earthquake ground motion that arise at extremely low probabilities of exceedance (hazard). They first came to our attention when the 1998 probabilistic seismic hazard analysis for Yucca Mountain was extended to a hazard level of 10-8/yr (a 10-4/yr probability for a 104-year repository “lifetime”). The primary purpose of this report is to summarize the principal results of the ExGM research program

  8. Expected impacts of climate change on extreme climate events

    International Nuclear Information System (INIS)

    Planton, S.; Deque, M.; Chauvin, F.; Terray, L.

    2008-01-01

    An overview of the expected change of climate extremes during this century due to greenhouse gases and aerosol anthropogenic emissions is presented. The most commonly used methodologies rely on the dynamical or statistical down-scaling of climate projections, performed with coupled atmosphere-ocean general circulation models. Either of dynamical or of statistical type, down-scaling methods present strengths and weaknesses, but neither their validation on present climate conditions, nor their potential ability to project the impact of climate change on extreme event statistics allows one to give a specific advantage to one of the two types. The results synthesized in the last IPCC report and more recent studies underline a convergence for a very likely increase in heat wave episodes over land surfaces, linked to the mean warming and the increase in temperature variability. In addition, the number of days of frost should decrease and the growing season length should increase. The projected increase in heavy precipitation events appears also as very likely over most areas and also seems linked to a change in the shape of the precipitation intensity distribution. The global trends for drought duration are less consistent between models and down-scaling methodologies, due to their regional variability. The change of wind-related extremes is also regionally dependent, and associated to a poleward displacement of the mid-latitude storm tracks. The specific study of extreme events over France reveals the high sensitivity of some statistics of climate extremes at the decadal time scale as a consequence of regional climate internal variability. (authors)

  9. A combination of extreme environmental conditions favor the prevalence of Endospore-forming Firmicutes

    Directory of Open Access Journals (Sweden)

    Sevasti Filippidou

    2016-11-01

    Full Text Available Environmental conditions unsuitable for microbial growth are the rule rather than the exception in most habitats. In response to this, microorganisms have developed various strategies to withstand environmental conditions that limit active growth. Endospore-forming Firmicutes (EFF deploy a myriad of survival strategies in order to resist adverse conditions. Like many bacterial groups, they can form biofilms and detect nutrient scarcity through chemotaxis. Moreover, within this paraphyletic group of Firmicutes, ecophysiological optima are diverse. Nonetheless, a response to adversity that delimits this group is the formation of wet-heat resistant spores. These strategies are energetically demanding and therefore might affect the biological success of EFF. Therefore, we hypothesize that abundance and diversity of EFF should be maximized in those environments in which the benefits of these survival strategies offsets the energetic cost. In order to address this hypothesis, geothermal and mineral springs and drillings were selected because in these environments of steep physicochemical gradients, diversified survival strategies may become a successful strategy. We collected 71 samples from geothermal and mineral environments characterized by none (null, single or multiple limiting environmental factors (temperature, pH, UV radiation and specific mineral composition. To measure success, we quantified EFF gene copy numbers (GCN; spo0A gene in relation to total bacterial GCN (16S rRNA gene, as well as the contribution of EFF to community composition. The quantification showed that relative GCN for EFF reached up to 20% at sites characterized by multiple limiting environmental factors, whereas it corresponded to less than 1% at sites with one or no limiting environmental factor. Pyrosequencing of the 16S rRNA gene supports a higher contribution of EFF at sites with multiple limiting factors. Community composition suggested a combination of phylotypes

  10. Large-scale Meteorological Patterns Associated with Extreme Precipitation Events over Portland, OR

    Science.gov (United States)

    Aragon, C.; Loikith, P. C.; Lintner, B. R.; Pike, M.

    2017-12-01

    Extreme precipitation events can have profound impacts on human life and infrastructure, with broad implications across a range of stakeholders. Changes to extreme precipitation events are a projected outcome of climate change that warrants further study, especially at regional- to local-scales. While global climate models are generally capable of simulating mean climate at global-to-regional scales with reasonable skill, resiliency and adaptation decisions are made at local-scales where most state-of-the-art climate models are limited by coarse resolution. Characterization of large-scale meteorological patterns associated with extreme precipitation events at local-scales can provide climatic information without this scale limitation, thus facilitating stakeholder decision-making. This research will use synoptic climatology as a tool by which to characterize the key large-scale meteorological patterns associated with extreme precipitation events in the Portland, Oregon metro region. Composite analysis of meteorological patterns associated with extreme precipitation days, and associated watershed-specific flooding, is employed to enhance understanding of the climatic drivers behind such events. The self-organizing maps approach is then used to characterize the within-composite variability of the large-scale meteorological patterns associated with extreme precipitation events, allowing us to better understand the different types of meteorological conditions that lead to high-impact precipitation events and associated hydrologic impacts. A more comprehensive understanding of the meteorological drivers of extremes will aid in evaluation of the ability of climate models to capture key patterns associated with extreme precipitation over Portland and to better interpret projections of future climate at impact-relevant scales.

  11. Using extreme value theory approaches to forecast the probability of outbreak of highly pathogenic influenza in Zhejiang, China.

    Directory of Open Access Journals (Sweden)

    Jiangpeng Chen

    Full Text Available Influenza is a contagious disease with high transmissibility to spread around the world with considerable morbidity and mortality and presents an enormous burden on worldwide public health. Few mathematical models can be used because influenza incidence data are generally not normally distributed. We developed a mathematical model using Extreme Value Theory (EVT to forecast the probability of outbreak of highly pathogenic influenza.The incidence data of highly pathogenic influenza in Zhejiang province from April 2009 to November 2013 were retrieved from the website of Health and Family Planning Commission of Zhejiang Province. MATLAB "VIEM" toolbox was used to analyze data and modelling. In the present work, we used the Peak Over Threshold (POT model, assuming the frequency as a Poisson process and the intensity to be Pareto distributed, to characterize the temporal variability of the long-term extreme incidence of highly pathogenic influenza in Zhejiang, China.The skewness and kurtosis of the incidence of highly pathogenic influenza in Zhejiang between April 2009 and November 2013 were 4.49 and 21.12, which indicated a "fat tail" distribution. A QQ plot and a mean excess plot were used to further validate the features of the distribution. After determining the threshold, we modeled the extremes and estimated the shape parameter and scale parameter by the maximum likelihood method. The results showed that months in which the incidence of highly pathogenic influenza is about 4462/2286/1311/487 are predicted to occur once every five/three/two/one year, respectively.Despite the simplicity, the present study successfully offers the sound modeling strategy and a methodological avenue to implement forecasting of an epidemic in the midst of its course.

  12. Autophagy sustains the survival of human pancreatic cancer PANC-1 cells under extreme nutrient deprivation conditions.

    Science.gov (United States)

    Kim, Sang Eun; Park, Hye-Jin; Jeong, Hye Kyoung; Kim, Mi-Jung; Kim, Minyeong; Bae, Ok-Nam; Baek, Seung-Hoon

    2015-07-31

    Pancreatic ductal adenocarcinomas are an extremely aggressive and devastating type of cancer with high mortality. Given the dense stroma and poor vascularization, accessibility to nutrients is limited in the tumor microenvironment. Here, we aimed to elucidate the role of autophagy in promoting the survival of human pancreatic cancer PANC-1 cells exposed to nutrient-deprived media (NDM) lacking glucose, amino acids, and serum. NDM inhibited Akt activity and phosphorylation of p70 S6K, and induced AMPK activation and mitochondrial depolarization. NDM also time-dependently increased LC3-II accumulation, number of GFP-LC3 puncta, and colocalization between GFP-LC3 and lysosomes. These results suggested that autophagy was progressively activated through Akt- and AMPK-mTOR pathway in nutrient-deficient PANC-1 cells. Autophagy inhibitors (chloroquine and wortmannin) or silencing of Atg5 augmented PANC-1 cell death in NDM. In cells exposed to NDM, chloroquine and wortmannin induced apoptosis and Z-VAD-fmk inhibited cytotoxicity of these inhibitors. These data demonstrate that autophagy is anti-apoptotic and sustains the survival of PANC-1 cells following extreme nutrient deprivation. Autophagy modulation may be a viable therapeutic option for cancer cells located in the core of solid tumors with a nutrient-deficient microenvironment. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    Science.gov (United States)

    Otero, Noelia Felipe; Sillmann, Jana; Schnell, Jordan L.; Rust, Henning W.; Butler, Tim

    2016-04-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8-hour average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over Southern Europe. In general, the best model performance is found over Central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  14. Life at extreme elevations on Atacama volcanoes: the closest thing to Mars on Earth?

    Science.gov (United States)

    Schmidt, S K; Gendron, E M S; Vincent, K; Solon, A J; Sommers, P; Schubert, Z R; Vimercati, L; Porazinska, D L; Darcy, J L; Sowell, P

    2018-03-20

    Here we describe recent breakthroughs in our understanding of microbial life in dry volcanic tephra ("soil") that covers much of the surface area of the highest elevation volcanoes on Earth. Dry tephra above 6000 m.a.s.l. is perhaps the best Earth analog for the surface of Mars because these "soils" are acidic, extremely oligotrophic, exposed to a thin atmosphere, high UV fluxes, and extreme temperature fluctuations across the freezing point. The simple microbial communities found in these extreme sites have among the lowest alpha diversity of any known earthly ecosystem and contain bacteria and eukaryotes that are uniquely adapted to these extreme conditions. The most abundant eukaryotic organism across the highest elevation sites is a Naganishia species that is metabolically versatile, can withstand high levels of UV radiation and can grow at sub-zero temperatures, and during extreme diurnal freeze-thaw cycles (e.g. - 10 to + 30 °C). The most abundant bacterial phylotype at the highest dry sites sampled (6330 m.a.s.l. on Volcán Llullaillaco) belongs to the enigmatic B12-WMSP1 clade which is related to the Ktedonobacter/Thermosporothrix clade that includes versatile organisms with the largest known bacterial genomes. Close relatives of B12-WMSP1 are also found in fumarolic soils on Volcán Socompa and in oligotrophic, fumarolic caves on Mt. Erebus in Antarctica. In contrast to the extremely low diversity of dry tephra, fumaroles found at over 6000 m.a.s.l. on Volcán Socompa support very diverse microbial communities with alpha diversity levels rivalling those of low elevation temperate soils. Overall, the high-elevation biome of the Atacama region provides perhaps the best "natural experiment" in which to study microbial life in both its most extreme setting (dry tephra) and in one of its least extreme settings (fumarolic soils).

  15. Vacuum-assisted closure downgrades reconstructive demands in high-risk patients with severe lower extremity injuries.

    Science.gov (United States)

    Kakagia, D; Karadimas, E; Drosos, G; Ververidis, A; Kazakos, D; Lazarides, M; Verettas, D

    2009-01-01

    Primary soft tissue reconstruction in complex leg injuries is mandatory in order to protect exposed tissues; however, it may be precluded by the patient's clinical status or by local wound conditions. This retrospective study aims to evaluate the use of negative pressure as an adjunct to delayed soft tissue reconstruction in patients with complex lower limb trauma. Forty-two patients with 49 complex lower limb injuries were treated with Vacuum assisted closure (VAC) 48 hours after bone fixation, vascular repair and surgical debridement. Wound swab cultures were obtained before and after every VAC application. Duration of therapy, wound flora, final reconstructive technique required, outcome and follow-up period were retrieved from medical records. Twenty-four male and eighteen female patients were recruited, with a mean age of 47 years. All were treated with VAC therapy for 15-42 days. Reconstruction was delayed due to the patients' critical condition, advanced age, medical co-morbidities, heavily exuding wounds and questionable viability of soft tissues. Patients were followed up for 90-895 days. Two wounds healed spontaneously, 6 were managed with delayed direct suture, 31 with split thickness skin grafts and 9 required local cutaneous, fasciocutaneous or muscular flaps. One patient died due to fat embolism. Wound bacterial flora progressively decreased in all but one patient. Scar formation was aesthetically acceptable by the patients while function depended on the initial injury. Negative pressure is a safe and effective adjunct to delayed soft tissue reconstruction in high-risk patients with severe lower extremity injuries, minimizing reconstructive requirements and therefore postoperative morbidity.

  16. PHASE QUANTIZATION STUDY OF SPATIAL LIGHT MODULATOR FOR EXTREME HIGH-CONTRAST IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    Dou, Jiangpei; Ren, Deqing, E-mail: jpdou@niaot.ac.cn, E-mail: jiangpeidou@gmail.com [Physics and Astronomy Department, California State University Northridge, 18111 Nordhoff Street, Northridge, CA 91330 (United States)

    2016-11-20

    Direct imaging of exoplanets by reflected starlight is extremely challenging due to the large luminosity ratio to the primary star. Wave-front control is a critical technique to attenuate the speckle noise in order to achieve an extremely high contrast. We present a phase quantization study of a spatial light modulator (SLM) for wave-front control to meet the contrast requirement of detection of a terrestrial planet in the habitable zone of a solar-type star. We perform the numerical simulation by employing the SLM with different phase accuracy and actuator numbers, which are related to the achievable contrast. We use an optimization algorithm to solve the quantization problems that is matched to the controllable phase step of the SLM. Two optical configurations are discussed with the SLM located before and after the coronagraph focal plane mask. The simulation result has constrained the specification for SLM phase accuracy in the above two optical configurations, which gives us a phase accuracy of 0.4/1000 and 1/1000 waves to achieve a contrast of 10{sup -10}. Finally, we have demonstrated that an SLM with more actuators can deliver a competitive contrast performance on the order of 10{sup -10} in comparison to that by using a deformable mirror.

  17. High-z X-ray Obscured Quasars in Galaxies with Extreme Mid-IR/Optical Colors

    Science.gov (United States)

    Piconcelli, E.; Lanzuisi, G.; Fiore, F.; Feruglio, C.; Vignali, C.; Salvato, M.; Grappioni, C.

    2009-05-01

    Extreme Optical/Mid-IR color cuts have been used to uncover a population of dust-enshrouded, mid-IR luminous galaxies at high redshifts. Several lines of evidence point towards the presence of an heavily absorbed, possibly Compton-thick quasar at the heart of these systems. Nonetheless, the X-ray spectral properties of these intriguing sources still remain largely unexplored. Here we present an X-ray spectroscopic study of a large sample of 44 extreme dust-obscured galaxies (EDOGs) with F24 μm/FR>2000 and F24 μm>1.3 mJy selected from a 6 deg2 region in the SWIRE fields. The application of our selection criteria to a wide area survey has been capable of unveiling a population of X-ray luminous, absorbed z>1 quasars which is mostly missed in the traditional optical/X-ray surveys performed so far. Advances in the understanding of the X-ray properties of these recently-discovered sources by Simbol-X observations will be also discussed.

  18. Test fields cannot destroy extremal black holes

    International Nuclear Information System (INIS)

    Natário, José; Queimada, Leonel; Vicente, Rodrigo

    2016-01-01

    We prove that (possibly charged) test fields satisfying the null energy condition at the event horizon cannot overspin/overcharge extremal Kerr–Newman or Kerr–Newman–anti de Sitter black holes, that is, the weak cosmic censorship conjecture cannot be violated in the test field approximation. The argument relies on black hole thermodynamics (without assuming cosmic censorship), and does not depend on the precise nature of the fields. We also discuss generalizations of this result to other extremal black holes. (paper)

  19. WEAK LINE QUASARS AT HIGH REDSHIFT: EXTREMELY HIGH ACCRETION RATES OR ANEMIC BROAD-LINE REGIONS?

    International Nuclear Information System (INIS)

    Shemmer, Ohad; Trakhtenbrot, Benny; Netzer, Hagai; Anderson, Scott F.; Brandt, W. N.; Schneider, Donald P.; Diamond-Stanic, Aleksandar M.; Fan Xiaohui; Lira, Paulina; Plotkin, Richard M.; Richards, Gordon T.; Strauss, Michael A.

    2010-01-01

    We present Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines (WLQs), SDSS J114153.34+021924.3 at z = 3.55 and SDSS J123743.08+630144.9 at z = 3.49. In both sources, we detect an unusually weak broad Hβ line and place tight upper limits on the strengths of their [O III] lines. Virial, Hβ-based black hole mass determinations indicate normalized accretion rates of L/L Edd =0.4 for these sources, which is well within the range observed for typical quasars with similar luminosities and redshifts. We also present high-quality XMM-Newton imaging spectroscopy of SDSS J114153.34+021924.3 and find a hard-X-ray photon index of Γ = 1.91 +0.24 -0.22 , which supports the virial L/L Edd determination in this source. Our results suggest that the weakness of the broad emission lines in WLQs is not a consequence of an extreme continuum-emission source but instead due to abnormal broad emission line region properties.

  20. A large, benign prostatic cyst presented with an extremely high serum prostate-specific antigen level.

    Science.gov (United States)

    Chen, Han-Kuang; Pemberton, Richard

    2016-01-08

    We report a case of a patient who presented with an extremely high serum prostate specific antigen (PSA) level and underwent radical prostatectomy for presumed prostate cancer. Surprisingly, the whole mount prostatectomy specimen showed only small volume, organ-confined prostate adenocarcinoma and a large, benign intraprostatic cyst, which was thought to be responsible for the PSA elevation. 2016 BMJ Publishing Group Ltd.

  1. Extreme summer temperatures in Iberia: health impacts and associated synoptic conditions

    OpenAIRE

    Garcia-Herrera , R.; Diaz , J.; Trigo , R. M.; Hernández , E.

    2005-01-01

    This paper examines the effect of extreme summer temperatures on daily mortality in two large cities of Iberia: Lisbon (Portugal) and Madrid (Spain). Daily mortality and meteorological variables are analysed using the same methodology based on Box-Jenkins models. Results reveal that in both cases there is a triggering effect on mortality when maximum daily temperature exceeds a given threshold (34°C in Lisbon and 36°C in Madrid). The impact of most intense heat events is very ...

  2. Extremely Elevated CA 125 and CA 19-9 in Endometrioma; A Case Series

    Directory of Open Access Journals (Sweden)

    Vugar Bayramov

    2010-03-01

    Full Text Available Although endometriosis is a benign condition, increased levels of the tumor markers CA 125 and CA 19-9 may be seen. However, these tumor markers reach to very high levels, rarely. In this report, 4 patients between 20 and 43 year-old with extremely elevated CA 125, CA 19-9 and CA 15-3 levels are discussed. In endometriosis extremely increased tumor markers are determined in the case of ruptured endometrioma cyst. There are two mechanisms to clarify extremely elevated levels of CA 125 in endometriosis. First, the peritoneal irritation of CA 125 molecule after the rupture of endometioma cyst and CA 125 secretion from the periton. And the second is penetration of the CA 125 moecule easily to the circulation through the peritoneal endothelial surface after the cyst rupture. In conclusion, the diagnosis of ruptured endometrioma cyst should be kept in mind especially in young patients with extremely elevated serum CA 125 levels with regard to the history and ultrasonographical signs and invasive procedures should be avoided.

  3. A Generalized Framework for Non-Stationary Extreme Value Analysis

    Science.gov (United States)

    Ragno, E.; Cheng, L.; Sadegh, M.; AghaKouchak, A.

    2017-12-01

    Empirical trends in climate variables including precipitation, temperature, snow-water equivalent at regional to continental scales are evidence of changes in climate over time. The evolving climate conditions and human activity-related factors such as urbanization and population growth can exert further changes in weather and climate extremes. As a result, the scientific community faces an increasing demand for updated appraisal of the time-varying climate extremes. The purpose of this study is to offer a robust and flexible statistical tool for non-stationary extreme value analysis which can better characterize the severity and likelihood of extreme climatic variables. This is critical to ensure a more resilient environment in a changing climate. Following the positive feedback on the first version of Non-Stationary Extreme Value Analysis (NEVA) Toolbox by Cheng at al. 2014, we present an improved version, i.e. NEVA2.0. The upgraded version herein builds upon a newly-developed hybrid evolution Markov Chain Monte Carlo (MCMC) approach for numerical parameters estimation and uncertainty assessment. This addition leads to a more robust uncertainty estimates of return levels, return periods, and risks of climatic extremes under both stationary and non-stationary assumptions. Moreover, NEVA2.0 is flexible in incorporating any user-specified covariate other than the default time-covariate (e.g., CO2 emissions, large scale climatic oscillation patterns). The new feature will allow users to examine non-stationarity of extremes induced by physical conditions that underlie the extreme events (e.g. antecedent soil moisture deficit, large-scale climatic teleconnections, urbanization). In addition, the new version offers an option to generate stationary and/or non-stationary rainfall Intensity - Duration - Frequency (IDF) curves that are widely used for risk assessment and infrastructure design. Finally, a Graphical User Interface (GUI) of the package is provided, making NEVA

  4. Desiccation and Mortality Dynamics in Seedlings of Different European Beech (Fagus sylvatica L.) Populations under Extreme Drought Conditions

    Science.gov (United States)

    Bolte, Andreas; Czajkowski, Tomasz; Cocozza, Claudia; Tognetti, Roberto; de Miguel, Marina; Pšidová, Eva; Ditmarová, Ĺubica; Dinca, Lucian; Delzon, Sylvain; Cochard, Hervè; Ræbild, Anders; de Luis, Martin; Cvjetkovic, Branislav; Heiri, Caroline; Müller, Jürgen

    2016-01-01

    European beech (Fagus sylvatica L., hereafter beech), one of the major native tree species in Europe, is known to be drought sensitive. Thus, the identification of critical thresholds of drought impact intensity and duration are of high interest for assessing the adaptive potential of European beech to climate change in its native range. In a common garden experiment with one-year-old seedlings originating from central and marginal origins in six European countries (Denmark, Germany, France, Romania, Bosnia-Herzegovina, and Spain), we applied extreme drought stress and observed desiccation and mortality processes among the different populations and related them to plant water status (predawn water potential, ΨPD) and soil hydraulic traits. For the lethal drought assessment, we used a critical threshold of soil water availability that is reached when 50% mortality in seedling populations occurs (LD50SWA). We found significant population differences in LD50SWA (10.5–17.8%), and mortality dynamics that suggest a genetic difference in drought resistance between populations. The LD50SWA values correlate significantly with the mean growing season precipitation at population origins, but not with the geographic margins of beech range. Thus, beech range marginality may be more due to climatic conditions than to geographic range. The outcome of this study suggests the genetic variation has a major influence on the varying adaptive potential of the investigated populations. PMID:27379105

  5. Extremes temperatures and enthalpy in Finland and Sweden in a changing climate

    International Nuclear Information System (INIS)

    Venaelaeinen, A.; Saku, S.; Jylhae, K.; Nikulin, G.; Kjellstroem, E.; Baerring, L.

    2009-06-01

    Though risks caused by harsh weather conditions are taken into account in the planning of nuclear power plants, some exceptional weather events or combination of different events may prevent normal power operation and simultaneously endanger safe shutdown of the plant. Extreme weather events could influence, for example, the external power grid connection, emergency diesel generators (blockage of air intakes), ventilation and cooling of electric and electronics equipment rooms and the seawater intake. Due to the influence of an intensified greenhouse effect the climate is changing rapidly during the coming decades and this change is expected to have an influence also on the occurrence of extreme weather events. In this report we have examined extreme temperatures. Enthalpy is a parameter that combines air temperature and air humidity and it is used in the design of air conditioning systems. Therefore, we have included also return levels of enthalpy in our analysis. The influence of climate change on extreme temperatures is analysed based on regional climate model simulations. The reoccurrence times of high temperatures combined with high air humidity was analysed based on measurements made at five Finnish and three Swedish meteorological stations. Based on the observational records we find the 10 year return level of daily maximum temperature to be around 32 deg. C and the 100 year return level around 35 deg. C. If we look the return levels of warm and humid conditions then for example in Helsinki the 10 year return level of one week mean temperature in case mean air humidity is above 80% is 20.1 deg. C. The 10 year return level of daily maximum enthalpy is around 60 kJ/kg and the 100 year return level almost 70 kJ/kg. According to the climate model simulations the largest increase of 50-year return level of daily maximum temperature is found in southern Sweden and south-western Finland. By the end of this century the increase can be 3-5 deg. C. The largest change

  6. Extremes temperatures and enthalpy in Finland and Sweden in a changing climate

    Energy Technology Data Exchange (ETDEWEB)

    Venaelaeinen, A.; Saku, S.; Jylhae, K. (Finnish Meteorological Institute (Finland)); Nikulin, G.; Kjellstroem, E.; Baerring, L. (Swedish Meteorological Institute (Sweden))

    2009-06-15

    Though risks caused by harsh weather conditions are taken into account in the planning of nuclear power plants, some exceptional weather events or combination of different events may prevent normal power operation and simultaneously endanger safe shutdown of the plant. Extreme weather events could influence, for example, the external power grid connection, emergency diesel generators (blockage of air intakes), ventilation and cooling of electric and electronics equipment rooms and the seawater intake. Due to the influence of an intensified greenhouse effect the climate is changing rapidly during the coming decades and this change is expected to have an influence also on the occurrence of extreme weather events. In this report we have examined extreme temperatures. Enthalpy is a parameter that combines air temperature and air humidity and it is used in the design of air conditioning systems. Therefore, we have included also return levels of enthalpy in our analysis. The influence of climate change on extreme temperatures is analysed based on regional climate model simulations. The reoccurrence times of high temperatures combined with high air humidity was analysed based on measurements made at five Finnish and three Swedish meteorological stations. Based on the observational records we find the 10 year return level of daily maximum temperature to be around 32 deg. C and the 100 year return level around 35 deg. C. If we look the return levels of warm and humid conditions then for example in Helsinki the 10 year return level of one week mean temperature in case mean air humidity is above 80% is 20.1 deg. C. The 10 year return level of daily maximum enthalpy is around 60 kJ/kg and the 100 year return level almost 70 kJ/kg. According to the climate model simulations the largest increase of 50-year return level of daily maximum temperature is found in southern Sweden and south-western Finland. By the end of this century the increase can be 3-5 deg. C. The largest change

  7. A comparison study of the two-bladed partial pitch turbine during normal operation and an extreme gust conditions

    International Nuclear Information System (INIS)

    Kim, T; Petersen, M M; Larsen, T J

    2014-01-01

    This paper shows the load comparisons between the numerical simulation and the full-scale load measurement data. First part of this paper includes the comparisons of statistic load in terms of maximum, mean, and minimum values for the selected normal operation cases. The blade root bending moments and tower top bending moments are compared. Second part of this paper introduces the dynamic response comparisons during an extreme wind gust condition where the wind speed changed approximately 10 m/s during three seconds. The rotor speed and blade root flapwise and edgewise bending moment are compared. The nonlinear aeroelastic simulation code HAWC2 is used for the simulations. A very fine agreement between the simulated and the full-scale measured loads is seen for the both comparisons

  8. Extreme temperatures increase the deleterious consequences of inbreeding under laboratory and semi-natural conditions

    DEFF Research Database (Denmark)

    Kristensen, Torsten Nygård; Barker, J. Stuart F.; Pedersen, Kamilla Sofie

    2008-01-01

    when compared with non-inbred lines of Drosophila melanogaster under different temperature conditions. Egg-to-adult viability, developmental time and sex ratio of emerging adults are studied under low, intermediate and high temperatures under laboratory as well as semi-natural conditions. The results...... show inbreeding depression for egg-to-adult viability. The level of inbreeding depression is highly dependent on test temperature and is observed only at low and high temperatures. Inbreeding did not affect the developmental time or the sex ratio of emerging adults. However, temperature affected...... the sex ratio with more females relative to males emerging at low temperatures, suggesting that selection against males in pre-adult life stages is stronger at low temperatures. The coefficient of variation (CV) of egg-to-adult viability within and among lines is higher for inbred flies and generally...

  9. MR imaging findings of high-voltage electrical burns in the upper extremities: correlation with angiographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Min, Seon Jung; Han, You Mi (Dept. of Radiology, Hallym Univ. College of Medicine, Hangang Sacred Heart Hospital, Seoul (Korea, Republic of)); Suh, Kyung Jin (Dept. of Radiology, Dongguk Univ. College of Medicine, Gyeongju Hospital, Gyeongju (Korea, Republic of)), email: kyungjin.suh@gmail.com; Choi, Min Ho (Dept. of Internal Medicine, Hallym Univ. College of Medicine, Hangang Sacred Heart Hospital, Seoul (Korea, Republic of))

    2011-02-15

    Background: A high-voltage electrical burn is often associated with deep muscle injuries. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, and this can lead to major amputations or sepsis. MRI has excellent soft tissue contrast and it may aid in differentiating the areas of viable deep muscle from the areas of non-viable deep muscle. Purpose: To describe the MR imaging findings of a high-voltage electrical burn in the upper extremity with emphasis on the usefulness of the gadolinium-enhanced MRI and to compare the MR imaging findings with angiography. Material and Methods: We retrospectively reviewed the imaging studies of six patients with high-voltage electrical burns who underwent both MRI and angiography at the burn center of our hospital from January 2005 to December 2009. The imaging features were evaluated for the involved locations, the MR signal intensity of the affected muscles, the MR enhancement pattern, the involved arteries and the angiographic findings (classified as normal, sluggish flow, stenosis or occlusion) of the angiography of the upper extremity. We assessed the relationship between the MR imaging findings and the angiographic findings. Results: The signal intensities of affected muscles were isointense or of slightly high signal intensity as compared with the adjacent unaffected skeletal muscle on the T1-weighted MR images. Affected muscles showed heterogenous high signal intensity relative to the adjacent unaffected skeletal muscle on the T2- weighted images. The gadolinium-enhanced T1-weighted images showed diffuse inhomogeneous enhancement or peripheral rim enhancement of the affected muscles. The angiographic findings of the arterial injuries showed complete occlusion in three patients, severe stenosis in two patients and sluggish flow in one patient. Of these, the five patients with complete occlusion or severe stenosis on angiography showed non-perfused and non-viable areas of edematous muscle on

  10. Radiosensitizing and toxic effects of the 2-nitroimidazole Ro-07-0582 in different phases of the cell cycle of extremely hypoxic human cells in vitro

    International Nuclear Information System (INIS)

    Petterson, E.O.

    1978-01-01

    The radiosensitizing effect of 5 and 30 mM of Ro-07-0582 (misonidazole) has been studied at different stages of the cell cycle of mitotically selected NHIK 3025 cells under aerobic and extremely hypoxic conditions. For cells irradiated under aerobic conditions no sensitizing effect was seen at any stage of the cell cycle. For cells irradiated under extremely hypoxic conditions there was a lower sensitizing effect in mid-G1 than in mid-S for low radiation doses (in the initial region of the dose-response curves). For high radiation doses, however, no significant difference in sensitizing effect on cells in mid-G1 and in mid-S was seen. For cells in mid-G1 the sensitizing effect increased with increasing radiation dose. The toxic effect of 30 mM Ro-07-0582 as measured by loss of reproductive capacity was studied at room temperature for contact times up to 6 hours under aerobic conditions and 3 hours under extremely hypoxic conditions. While no effect was seen under aerobic conditions there was a toxic effect for contact intervals above 1 hour under extremely hypoxic conditions. Cells in S were more sensitive to the toxic effect of Ro-07-0582 than cells in G1. Implications for clinical use are discussed

  11. SOI N-Channel Field Effect Transistors, CHT-NMOS80, for Extreme Temperatures

    Science.gov (United States)

    Patterson, Richard L.; Hammoud, Almad

    2009-01-01

    Extreme temperatures, both hot and cold, are anticipated in many of NASA space exploration missions as well as in terrestrial applications. One can seldom find electronics that are capable of operation under both regimes. Even for operation under one (hot or cold) temperature extreme, some thermal controls need to be introduced to provide appropriate ambient temperatures so that spacecraft on-board or field on-site electronic systems work properly. The inclusion of these controls, which comprise of heating elements and radiators along with their associated structures, adds to the complexity in the design of the system, increases cost and weight, and affects overall reliability. Thus, it would be highly desirable and very beneficial to eliminate these thermal measures in order to simplify system's design, improve efficiency, reduce development and launch costs, and improve reliability. These requirements can only be met through the development of electronic parts that are designed for proper and efficient operation under extreme temperature conditions. Silicon-on-insulator (SOI) based devices are finding more use in harsh environments due to the benefits that their inherent design offers in terms of reduced leakage currents, less power consumption, faster switching speeds, good radiation tolerance, and extreme temperature operability. Little is known, however, about their performance at cryogenic temperatures and under wide thermal swings. The objective of this work was to evaluate the performance of a new commercial-off-the-shelf (COTS) SOI parts over an extended temperature range and to determine the effects of thermal cycling on their performance. The results will establish a baseline on the suitability of such devices for use in space exploration missions under extreme temperatures, and will aid mission planners and circuit designers in the proper selection of electronic parts and circuits. The electronic part investigated in this work comprised of a CHT-NMOS80

  12. Influence of Anthropogenic Climate Change on Planetary Wave Resonance and Extreme Weather Events.

    Science.gov (United States)

    Mann, Michael E; Rahmstorf, Stefan; Kornhuber, Kai; Steinman, Byron A; Miller, Sonya K; Coumou, Dim

    2017-03-27

    Persistent episodes of extreme weather in the Northern Hemisphere summer have been shown to be associated with the presence of high-amplitude quasi-stationary atmospheric Rossby waves within a particular wavelength range (zonal wavenumber 6-8). The underlying mechanistic relationship involves the phenomenon of quasi-resonant amplification (QRA) of synoptic-scale waves with that wavenumber range becoming trapped within an effective mid-latitude atmospheric waveguide. Recent work suggests an increase in recent decades in the occurrence of QRA-favorable conditions and associated extreme weather, possibly linked to amplified Arctic warming and thus a climate change influence. Here, we isolate a specific fingerprint in the zonal mean surface temperature profile that is associated with QRA-favorable conditions. State-of-the-art ("CMIP5") historical climate model simulations subject to anthropogenic forcing display an increase in the projection of this fingerprint that is mirrored in multiple observational surface temperature datasets. Both the models and observations suggest this signal has only recently emerged from the background noise of natural variability.

  13. Modeling and evaluation of a high-resolution CMOS detector for cone-beam CT of the extremities.

    Science.gov (United States)

    Cao, Qian; Sisniega, Alejandro; Brehler, Michael; Stayman, J Webster; Yorkston, John; Siewerdsen, Jeffrey H; Zbijewski, Wojciech

    2018-01-01

    Quantitative assessment of trabecular bone microarchitecture in extremity cone-beam CT (CBCT) would benefit from the high spatial resolution, low electronic noise, and fast scan time provided by complementary metal-oxide semiconductor (CMOS) x-ray detectors. We investigate the performance of CMOS sensors in extremity CBCT, in particular with respect to potential advantages of thin (CMOS x-ray detector incorporating the effects of CsI:Tl scintillator thickness was developed. Simulation studies were performed using nominal extremity CBCT acquisition protocols (90 kVp, 0.126 mAs/projection). A range of scintillator thickness (0.35-0.75 mm), pixel size (0.05-0.4 mm), focal spot size (0.05-0.7 mm), magnification (1.1-2.1), and dose (15-40 mGy) was considered. The detectability index was evaluated for both CMOS and a-Si:H flat-panel detector (FPD) configurations for a range of imaging tasks emphasizing spatial frequencies associated with feature size aobj. Experimental validation was performed on a CBCT test bench in the geometry of a compact orthopedic CBCT system (SAD = 43.1 cm, SDD = 56.0 cm, matching that of the Carestream OnSight 3D system). The test-bench studies involved a 0.3 mm focal spot x-ray source and two CMOS detectors (Dalsa Xineos-3030HR, 0.099 mm pixel pitch) - one with the standard CsI:Tl thickness of 0.7 mm (C700) and one with a custom 0.4 mm thick scintillator (C400). Measurements of modulation transfer function (MTF), detective quantum efficiency (DQE), and CBCT scans of a cadaveric knee (15 mGy) were obtained for each detector. Optimal detectability for high-frequency tasks (feature size of ~0.06 mm, consistent with the size of trabeculae) was ~4× for the C700 CMOS detector compared to the a-Si:H FPD at nominal system geometry of extremity CBCT. This is due to ~5× lower electronic noise of a CMOS sensor, which enables input quantum-limited imaging at smaller pixel size. Optimal pixel size for high-frequency tasks was CMOS

  14. Validation of nonlinear FEA models of a thin-walled elbow under extreme loading conditions for Sodium-cooled Fast Reactors

    International Nuclear Information System (INIS)

    Watakabe, Tomoyoshi; Wakai, Takashi; Jin, Chuanrong; Usui, Yoshiya; Sakai, Shinkichi; Ooshika, Junji; Tsukimori, Kazuyuki

    2015-01-01

    For the purpose of confirming failure modes and safety margin, some studies on the ultimate strength of thin-walled piping components for Sodium-cooled Fast Reactors (SFRs) under extreme loading conditions such as large earthquakes have been reported these several years. Nonlinear finite element analysis has been applied in these studies to simulate buckling and yielding with large deformation, whose accuracy is dependent on the element type, the mesh size, the elasto-plastic model and so on. It is important to check the validation of a finite element model for nonlinear analysis especially under extreme loading conditions. This paper presents static and dynamic analyses of a thin-walled elbow with large deformation under large seismic loading, and discusses the validation of the FEA models comparing with experimental results. The finite element analysis models in this study are generated by shell elements for a stainless steel pipe elbow of diameter-to-thickness ratio 59:1 similar to the main pipe of SFRs, which is used for shaking table tests. At first, a static analysis is carried out for an in-plane monotonic bending test, in order to confirm that the shell element is appropriate to the large deformation analysis and the material parameters are proper for the strain level in the experiments. And then, a dynamic in-plane bending test with the maximum acceleration of 11.7G is simulated by the nonlinear FEA with stiffness-proportional damping. The influence of mesh sizes on results is investigated, to determine proper mesh sizes and reduce the computational cost. Finally, comparing the results of the FEM analyses with those of experiments, it is concluded that the appropriately generated FEA models are effective and give accurate results for nonlinear analyses of the thin-walled elbow under large seismic loading. (author)

  15. Exertional Heat Illnesses and Environmental Conditions During High School Football Practices.

    Science.gov (United States)

    Tripp, Brady L; Eberman, Lindsey E; Smith, Michael Seth

    2015-10-01

    Guidelines for preventing exertional heat illnesses (EHIs) during extreme heat stress should be specific to regional environments, age, and sport and should be based on evidence of reducing the risk. Each year in the United States, over 1 million high school football players practice in the August heat; however, no published data describe the incidence of EHIs in these athletes. To describe the environmental conditions and incidence of EHIs during high school football practices over a 3-month period. Descriptive epidemiology study. For a 3-month period (August-October), athletic trainers at 12 high schools in North Central Florida recorded the practice time and length, environmental conditions (wet-bulb globe temperature), and incidences of EHIs in varsity football athletes. Athletes suffered 57 total EHIs during 29,759 athlete-exposures (AEs) for the 3-month data collection period (rate = 1.92/1000 AEs). August accounted for the majority of all EHIs, with 82.5% (47/57) and the highest rate (4.35/1000 AEs). Of total heat illnesses, heat cramps accounted for 70.2% (40/57), heat exhaustion 22.8% (13/57), and heat syncope 7.0% (4/57). The odds ratio indicated that athletes in August practices that lasted longer than the recommended 3 hours were 9.84 times more likely to suffer a heat illness than those in practices lasting ≤3 hours. The highest rate of EHIs was during August. Practices in August that exceeded the recommended 3 hours were associated with a greater risk of heat illnesses. The overall rate of EHIs was lower for the high school football athletes observed in the study compared with that reported for collegiate football athletes in the region. The low rates of EHIs recorded suggest that the prevention guidelines employed by sports medicine teams are appropriate for the region and population. Team physicians and athletic trainers should employ evidence-based, region- and population-specific EHI prevention guidelines. Sports medicine teams, coaches, and

  16. Hexafluorobenzene under Extreme Conditions.

    Science.gov (United States)

    Pravica, Michael; Sneed, Daniel; Wang, Yonggang; Smith, Quinlan; White, Melanie

    2016-03-17

    We report the results from three high pressure experiments on hexafluorobenzene (C6F6). In the first experiment, Raman spectra were recorded up to 34.4 GPa. A phase transition from I → II was observed near 2 GPa. Near 8.8 GPa, a phase transition to an unreported phase (III) commenced. Above 20.6 GPa, yet another phase was observed (IV). Pressure cycling was employed to determine that, below 25.6 GPa, all pressure-induced alterations were reversible. However, at pressures above 20 GPa, dramatic spectral changes and broadening were observed at 25.6 and 34.4 GPa. The sample irreversibly changed into a soft solid with waxlike consistency when pressure was reduced to ambient and was recoverable. In the second experiment, IR spectra were collected up to 14.6 GPa. The phase transition (II → III) near 8.8 GPa was confirmed. An angular dispersive X-ray diffraction experiment was conducted to 25.6 GPa. Phase transitions above 1.4 GPa (I → II), above 5.5 GPa (II → III), above 10 GPa (III → IV), and above 15.5 GPa (IV → V) were observed. Near 25.6 GPa, long-range crystalline order was lost as the X-ray diffraction spectrum presented evidence of an amorphous solid.

  17. Improving the diffraction of apoA-IV crystals through extreme dehydration

    International Nuclear Information System (INIS)

    Deng, Xiaodi; Davidson, W. Sean; Thompson, Thomas B.

    2011-01-01

    Apolipoprotein A-IV crystals consisted of a long unit-cell edge (540 Å) with a high mosaic spread, making them intractable for X-ray diffraction analysis. Extreme dehydration in 60% PEG 3350 was utilized as a post-crystallization treatment as well a screening method to significantly sharpen the mosaic spread and increase the overall resolution of diffraction. Apolipoproteins are the protein component of high-density lipoproteins (HDL), which are necessary for mobilizing lipid-like molecules throughout the body. Apolipoproteins undergo self-association, especially at higher concentrations, making them difficult to crystallize. Here, the crystallization and diffraction of the core fragment of apolipoprotein A-IV (apoA-IV), consisting of residues 64–335, is presented. ApoA-IV 64–335 crystallized readily in a variety of hexagonal (P6) morphologies with similar unit-cell parameters, all containing a long axis of nearly 550 Å in length. Preliminary diffraction experiments with the different crystal morphologies all resulted in limited streaky diffraction to 3.5 Å resolution. Crystal dehydration was applied to the different morphologies with variable success and was also used as a quality indicator of crystal-growth conditions. The results show that the morphologies that withstood the most extreme dehydration conditions showed the greatest improvement in diffraction. One morphology in particular was able to withstand dehydration in 60% PEG 3350 for over 12 h, which resulted in well defined intensities to 2.7 Å resolution. These results suggest that the approach of integrating dehydration with variation in crystal-growth conditions might be a general technique to optimize diffraction

  18. High-pressure behavior and crystal–fluid interaction under extreme conditions in paulingite [PAU-topology

    Czech Academy of Sciences Publication Activity Database

    Gatta, G. D.; Scheidl, K. S.; Pippinger, T.; Skála, Roman; Lee, J.; Miletich, R.

    2015-01-01

    Roč. 206, April (2015), s. 34-41 ISSN 1387-1811 Institutional support: RVO:67985831 Keywords : paulingite * high pressure * X-ray diffraction * compressibility * crystal–fluid interaction Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.349, year: 2015

  19. Extreme Heat: A Prevention Guide to Promote Your Personal Health and Safety

    Science.gov (United States)

    ... Extreme Heat Older Adults (Aged 65+) Infants and Children Chronic Medical Conditions Low Income Athletes Outdoor Workers Pets Hot Weather Tips Warning Signs and Symptoms FAQs Social Media How to Stay Cool Missouri Cooling Centers Extreme ...

  20. High dark matter densities and the formation of extreme dwarf galaxies

    International Nuclear Information System (INIS)

    Lake, G.

    1990-01-01

    The extreme dwarfs of the Local Group, GR 8, Draco, and Ursa Minor have high densities of dark matter. If the dark matter is dissipationless, then there is a simple relation between the redshift of turnaround z(turn) and its current mean density. Three alternatives for the dSphs are discussed. If the dark matter follows the light, then z(turn) is greater than 30. If a density profile is adopted so that the mean density becomes low enough to be barely consistent with the standard density fluctuation spectrum of cold dark matter, then the mass-to-light ratios are greater than 1000 solar mass/solar luminosity. The last alternative is dissipational dark matter. In this case, the additional collapse factor owing to dissipation allows a later epoch of formation. 39 refs

  1. HE0359-3959: An Extremely Radiating Quasar

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-Aldama, M. L.; Del Olmo, A. [Instituto de Astrofísica de Andalucía, IAA-CSIC, Granada (Spain); Marziani, P. [INAF, Osservatorio Astronomico di Padova, Padua (Italy); Negrete, C. A. [CONACYT Research Fellow, Instituto de Astronomía, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Dultzin, D. [Instituto de Astronomía, Universidad Nacional Autonoma de Mexico, Mexico City (Mexico); Martínez-Carballo, M. A., E-mail: maryloli@iaa.es [Instituto de Astrofísica de Andalucía, IAA-CSIC, Granada (Spain)

    2017-11-28

    We present a multiwavelength spectral study of the quasar HE0359-3959, which has been identified as an extreme radiating source at intermediate redshift (z = 1.5209). Along the spectral range, the different ionic species give information about the substructures in the broad line region. The presence of a powerful outflow with an extreme blueshifted velocity of ~–6,000 ± 500 km s{sup −1} is shown in the Civλ1549 emission line. A prominent blueshifted component is also associated with the 1900Å blend, resembling the one observed in Civλ1549. We detect a strong contribution of very the low–ionization lines, Feii and Near-Infrared Ca ii triplet. We find that the physical conditions for the low, intermediate, and high–ionization emission lines are different, which indicate that the emission lines are emitted in different zones of the broad line region. The asymmetries shown by the profiles reveal different forces over emitter zones. The high–ionization region is strongly dominated by radiation forces, which also affect the low and intermediate–ionization emitter region, commonly governed by virial motions. These results support the idea that highly radiating sources host a slim disk.

  2. Future intensification of hydro-meteorological extremes: downscaling using the weather research and forecasting model

    KAUST Repository

    El-Samra, R.

    2017-02-15

    A set of ten downscaling simulations at high spatial resolution (3 km horizontally) were performed using the Weather Research and Forecasting (WRF) model to generate future climate projections of annual and seasonal temperature and precipitation changes over the Eastern Mediterranean (with a focus on Lebanon). The model was driven with the High Resolution Atmospheric Model (HiRAM), running over the whole globe at a resolution of 25 km, under the conditions of two Representative Concentration Pathways (RCP) (4.5 and 8.5). Each downscaling simulation spanned one year. Two past years (2003 and 2008), also forced by HiRAM without data assimilation, were simulated to evaluate the model’s ability to capture the cold and wet (2003) and hot and dry (2008) extremes. The downscaled data were in the range of recent observed climatic variability, and therefore corrected for the cold bias of HiRAM. Eight future years were then selected based on an anomaly score that relies on the mean annual temperature and accumulated precipitation to identify the worst year per decade from a water resources perspective. One hot and dry year per decade, from 2011 to 2050, and per scenario was simulated and compared to the historic 2008 reference. The results indicate that hot and dry future extreme years will be exacerbated and the study area might be exposed to a significant decrease in annual precipitation (rain and snow), reaching up to 30% relative to the current extreme conditions.

  3. Extreme ultra-violet emission spectroscopy of highly charged gadolinium ions with an electron beam ion trap

    International Nuclear Information System (INIS)

    Ohashi, Hayato; Nakamura, Nobuyuki; Sakaue, Hiroyuki A

    2013-01-01

    We present extreme ultra-violet emission spectra of highly charged gadolinium ions obtained with an electron beam ion trap at electron energies of 0.53–1.51 keV. The electron energy dependence of the spectra in the 5.7–11.3 nm range is compared with calculation with the flexible atomic code. (paper)

  4. Extremely high magnetoresistance and conductivity in the type-II Weyl semimetals WP2 and MoP2.

    Science.gov (United States)

    Kumar, Nitesh; Sun, Yan; Xu, Nan; Manna, Kaustuv; Yao, Mengyu; Süss, Vicky; Leermakers, Inge; Young, Olga; Förster, Tobias; Schmidt, Marcus; Borrmann, Horst; Yan, Binghai; Zeitler, Uli; Shi, Ming; Felser, Claudia; Shekhar, Chandra

    2017-11-21

    The peculiar band structure of semimetals exhibiting Dirac and Weyl crossings can lead to spectacular electronic properties such as large mobilities accompanied by extremely high magnetoresistance. In particular, two closely neighboring Weyl points of the same chirality are protected from annihilation by structural distortions or defects, thereby significantly reducing the scattering probability between them. Here we present the electronic properties of the transition metal diphosphides, WP 2 and MoP 2 , which are type-II Weyl semimetals with robust Weyl points by transport, angle resolved photoemission spectroscopy and first principles calculations. Our single crystals of WP 2 display an extremely low residual low-temperature resistivity of 3 nΩ cm accompanied by an enormous and highly anisotropic magnetoresistance above 200 million % at 63 T and 2.5 K. We observe a large suppression of charge carrier backscattering in WP 2 from transport measurements. These properties are likely a consequence of the novel Weyl fermions expressed in this compound.

  5. Gene adaptation to extreme environments

    International Nuclear Information System (INIS)

    Marlaire, P.; Rodriguez, V.; Kerner, N.

    2005-01-01

    Full text: This work is oriented to the study of gene adaptation to extreme conditions, such as the hydrothermal system located in Copahue, Neuquen, Argentina. The organisms living there develop under two pressure selection conditions: the high temperature of thermal water and the strong impact of ultraviolet (UV) radiation. Several microorganisms found in this region were isolated and different colonies resistant to UV radiation were selected, a Geobacillus thermoleovorans strain identified through 16S RNA sequence, being the most remarkable. A gene library was prepared out of this strain with UV sensitive bacteria BH200 (uvrA::Tn10). A number of clones were isolated by means of UV selection, the most outstanding being a gene carrier able to codify for the guanosine monophosphate synthetase enzyme (GMPs). The suitability of said enzyme was proved by means of additional assays performed on ght 1 bacteria (guaA26::Tn 10) which lacked the enzyme. A transcript of 1100 pb was detected through Northern Blot. The result was consistent with that obtained for the mapping of the starting transcription site. The cloned GMPs produces an increase in growth speed and a greater biomass in BH200 bacteria. (author)

  6. Upper-extremity phocomelia reexamined: a longitudinal dysplasia.

    Science.gov (United States)

    Goldfarb, Charles A; Manske, Paul R; Busa, Riccardo; Mills, Janith; Carter, Peter; Ezaki, Marybeth

    2005-12-01

    In contrast to longitudinal deficiencies, phocomelia is considered a transverse, intercalated segmental dysplasia. Most patients demonstrate severe, but not otherwise classifiable, upper-extremity deformities, which usually cannot be placed into one of three previously described phocomelia groups. Additionally, these phocomelic extremities do not demonstrate true segmental deficits; the limb is also abnormal proximal and distal to the segmental defect. The purpose of this investigation was to present evidence that upper-extremity abnormalities in patients previously diagnosed as having phocomelia in fact represent a proximal continuum of radial or ulnar longitudinal dysplasia. The charts and radiographs of forty-one patients (sixty extremities) diagnosed as having upper-extremity phocomelia were reviewed retrospectively. On the basis of the findings on the radiographs, the disorders were categorized into three groups: (1) proximal radial longitudinal dysplasia, which was characterized by an absent proximal part of the humerus, a nearly normal distal part of the humerus, a completely absent radius, and a radial-sided hand dysplasia; (2) proximal ulnar longitudinal dysplasia, characterized by a short one-bone upper extremity that bifurcated distally and by severe hand abnormalities compatible with ulnar dysplasia; and (3) severe combined dysplasia, with type A characterized by an absence of the forearm segment (i.e., the radius and ulna) and type B characterized by absence of the arm and forearm (i.e., the hand attached to the thorax). Twenty-nine limbs in sixteen patients could be classified as having proximal radial longitudinal dysplasia. Systemic medical conditions such as thrombocytopenia-absent radius syndrome were common in those patients, but additional musculoskeletal conditions were rare. Twenty limbs in seventeen patients could be classified as having proximal ulnar longitudinal dysplasia. Associated musculoskeletal abnormalities, such as proximal femoral

  7. CO2-Philic polymer membrane with extremely high separation performance

    KAUST Repository

    Yave, Wilfredo

    2010-01-12

    Polymeric membranes are attractive for CO2 separation and concentration from different gas streams because of their versatility and energy efficiency; they can compete with, and they may even replace, traditional absorption processes. Here we describe a simple and powerful method for developing nanostructured and CO2-philic polymer membranes for CO2 separation. A poly(ethylene oxide)-poly(butylene terephthalate) multiblock copolymer is used as membrane material. Smart additives such as polyethylene glycol dibutyl ether are incorporated as spacers or fillers for producing nanostructured materials. The addition of these specific additives produces CO2-philic membranes and increases the CO2 permeability (750 barrer) up to five-fold without the loss of selectivity. The membranes present outstanding performance for CO2 separation, and the measured CO2 flux is extremely high ( > 2 m3 m -2 h-1 bar-1) with selectivity over H2 and N2 of 10 and 40, respectively, making them attractive for CO 2 capture. © 2009 American Chemical Society.

  8. CO2-Philic polymer membrane with extremely high separation performance

    KAUST Repository

    Yave, Wilfredo; Car, Anja; Funari, S.; Nunes, Suzana Pereira; Peinemann, Klaus-Viktor

    2010-01-01

    Polymeric membranes are attractive for CO2 separation and concentration from different gas streams because of their versatility and energy efficiency; they can compete with, and they may even replace, traditional absorption processes. Here we describe a simple and powerful method for developing nanostructured and CO2-philic polymer membranes for CO2 separation. A poly(ethylene oxide)-poly(butylene terephthalate) multiblock copolymer is used as membrane material. Smart additives such as polyethylene glycol dibutyl ether are incorporated as spacers or fillers for producing nanostructured materials. The addition of these specific additives produces CO2-philic membranes and increases the CO2 permeability (750 barrer) up to five-fold without the loss of selectivity. The membranes present outstanding performance for CO2 separation, and the measured CO2 flux is extremely high ( > 2 m3 m -2 h-1 bar-1) with selectivity over H2 and N2 of 10 and 40, respectively, making them attractive for CO 2 capture. © 2009 American Chemical Society.

  9. Very high cycle fatigue crack initiation in electroplated Ni films under extreme stress gradients

    International Nuclear Information System (INIS)

    Baumert, E.K.; Pierron, O.N.

    2012-01-01

    A characterization technique based on kilohertz micro-resonators is presented to investigate the very high cycle fatigue behavior of 20 μm thick electroplated Ni films with a columnar microstructure (grain diameter less than 2 μm). The films exhibit superior fatigue resistance due to the extreme stress gradients at the surface. The effects of stress amplitude and environment on the formation of fatigue extrusions and micro-cracks are discussed based on scanning electron microscopy and the tracking of the specimens’ resonant frequency.

  10. Future Projection of Summer Extreme Precipitation from High Resolution Multi-RCMs over East Asia

    Science.gov (United States)

    Kim, Gayoung; Park, Changyong; Cha, Dong-Hyun; Lee, Dong-Kyou; Suh, Myoung-Seok; Ahn, Joong-Bae; Min, Seung-Ki; Hong, Song-You; Kang, Hyun-Suk

    2017-04-01

    Recently, the frequency and intensity of natural hazards have been increasing due to human-induced climate change. Because most damages of natural hazards over East Asia have been related to extreme precipitation events, it is important to estimate future change in extreme precipitation characteristics caused by climate change. We investigate future changes in extremal values of summer precipitation simulated by five regional climate models participating in the CORDEX-East Asia project (i.e., HadGEM3-RA, RegCM4, MM5, WRF, and GRIMs) over East Asia. 100-year return value calculated from the generalized extreme value (GEV) parameters is analysed as an indicator of extreme intensity. In the future climate, the mean values as well as the extreme values of daily precipitation tend to increase over land region. The increase of 100-year return value can be significantly associated with the changes in the location (intensity) and scale (variability) GEV parameters for extreme precipitation. It is expected that the results of this study can be used as fruitful references when making the policy of disaster management. Acknowledgements The research was supported by the Ministry of Public Safety and Security of Korean government and Development program under grant MPSS-NH-2013-63 and the National Research Foundation of Korea Grant funded by the Ministry of Science, ICT and Future Planning of Korea (NRF-2016M3C4A7952637) for its support and assistant in completion of the study.

  11. Extreme waves at Filyos, southern Black Sea

    Directory of Open Access Journals (Sweden)

    E. Bilyay

    2011-03-01

    Full Text Available A wave measurement project was carried out for a new port planned in Filyos, in the Western Black Sea region of Turkey. The measurement at a depth of 12.5 m lasted for a period of two years and 7949 records were obtained. During the analysis, it was noticed that there were 209 records in which H/Hs ratio was higher than 2.0. These higher waves in a record are called extreme waves in this study. Although the purpose of wave measurement is not to investigate extreme waves, it is believed that studying these unexpected waves could be interesting. Therefore, detailed statistical and spectral analyses on the extreme waves were done for the records. The analyses results show that the distribution of surface profiles of the records containing extreme waves deviates from Gaussian distribution with the negative skewness changing between –0.01 and –0.4 and with the high kurtosis in the range of 3.1–4.2. Although the probability of occurrence of the extreme waves is over-predicted by the Rayleigh distribution, a higher ratio of Hsrms indicates that the wave height distribution can be represented by Rayleigh. The average value of the slope of the frequency spectrum at the high frequency range is proportional to f–9 which is much steeper than the typical wind-wave frequency power law, f–4, –5. The directional spreading is measured with the parameter Smax and it is in the range of 5–70 for the extreme wave records. The wave and current interaction was also investigated and it was found that in most cases, extreme waves occur when the wave and the current are almost aligned. Furthermore, it is observed that extreme waves appear within a group of high waves.

  12. Investigating NARCCAP Precipitation Extremes via Bivariate Extreme Value Theory (Invited)

    Science.gov (United States)

    Weller, G. B.; Cooley, D. S.; Sain, S. R.; Bukovsky, M. S.; Mearns, L. O.

    2013-12-01

    We introduce methodology from statistical extreme value theory to examine the ability of reanalysis-drive regional climate models to simulate past daily precipitation extremes. Going beyond a comparison of summary statistics such as 20-year return values, we study whether the most extreme precipitation events produced by climate model simulations exhibit correspondence to the most extreme events seen in observational records. The extent of this correspondence is formulated via the statistical concept of tail dependence. We examine several case studies of extreme precipitation events simulated by the six models of the North American Regional Climate Change Assessment Program (NARCCAP) driven by NCEP reanalysis. It is found that the NARCCAP models generally reproduce daily winter precipitation extremes along the Pacific coast quite well; in contrast, simulation of past daily summer precipitation extremes in a central US region is poor. Some differences in the strength of extremal correspondence are seen in the central region between models which employ spectral nudging and those which do not. We demonstrate how these techniques may be used to draw a link between extreme precipitation events and large-scale atmospheric drivers, as well as to downscale extreme precipitation simulated by a future run of a regional climate model. Specifically, we examine potential future changes in the nature of extreme precipitation along the Pacific coast produced by the pineapple express (PE) phenomenon. A link between extreme precipitation events and a "PE Index" derived from North Pacific sea-surface pressure fields is found. This link is used to study PE-influenced extreme precipitation produced by a future-scenario climate model run.

  13. EPS-LASSO: Test for High-Dimensional Regression Under Extreme Phenotype Sampling of Continuous Traits.

    Science.gov (United States)

    Xu, Chao; Fang, Jian; Shen, Hui; Wang, Yu-Ping; Deng, Hong-Wen

    2018-01-25

    Extreme phenotype sampling (EPS) is a broadly-used design to identify candidate genetic factors contributing to the variation of quantitative traits. By enriching the signals in extreme phenotypic samples, EPS can boost the association power compared to random sampling. Most existing statistical methods for EPS examine the genetic factors individually, despite many quantitative traits have multiple genetic factors underlying their variation. It is desirable to model the joint effects of genetic factors, which may increase the power and identify novel quantitative trait loci under EPS. The joint analysis of genetic data in high-dimensional situations requires specialized techniques, e.g., the least absolute shrinkage and selection operator (LASSO). Although there are extensive research and application related to LASSO, the statistical inference and testing for the sparse model under EPS remain unknown. We propose a novel sparse model (EPS-LASSO) with hypothesis test for high-dimensional regression under EPS based on a decorrelated score function. The comprehensive simulation shows EPS-LASSO outperforms existing methods with stable type I error and FDR control. EPS-LASSO can provide a consistent power for both low- and high-dimensional situations compared with the other methods dealing with high-dimensional situations. The power of EPS-LASSO is close to other low-dimensional methods when the causal effect sizes are small and is superior when the effects are large. Applying EPS-LASSO to a transcriptome-wide gene expression study for obesity reveals 10 significant body mass index associated genes. Our results indicate that EPS-LASSO is an effective method for EPS data analysis, which can account for correlated predictors. The source code is available at https://github.com/xu1912/EPSLASSO. hdeng2@tulane.edu. Supplementary data are available at Bioinformatics online. © The Author (2018). Published by Oxford University Press. All rights reserved. For Permissions, please

  14. [Body condition and metabolic stability as the basis for high milk yield and undisturbed fertility in dairy cows--a contribution for deduction of reference values].

    Science.gov (United States)

    Staufenbiel, R; Arndt, G; Schröder, U; Gelfert, C C

    2004-05-01

    The target of this study was to describe the interactions between body condition and various descriptors of yield and fertility. It was aimed to identify an optimal conditional range to be used in herd management which combines high milk yield with acceptable fertility traits and general health. For this purpose, backfat thickness was measured by ultrasound at 46111 dairy cows on 78 different farms and was subsequently related to production variables. Negative energy balance is getting more intense and prolonged with increasing milk yield. However a conditional nadir below 10 mm leads to decreased milk production. To reach a high production level without an increasing incidence of health disorders, conditional nadir should not decline below 13 mm backfat thickness on herd average. Lower value only lead to negligibly higher milk yield but cause a distinctively higher risk of fertility problems and culling. High herd yields do not have to be at expense of reproduction performance and can be achieved without extreme body condition losses. An efficient herd management can offset depression in fertility, which commonly is combined with increasing milk yield. A standard curve for backfat thickness throughout lactation is suggested to be used in dairy herd management.

  15. Extremely Short Optical Pulses and Ads/CFT Compliance

    Directory of Open Access Journals (Sweden)

    Konobeeva N.N.

    2015-01-01

    Full Text Available Dynamics of few cycle optical pulses in non-Fermi liquid was considered. Energy spectrum of non-Fermi liquid was taken from the AdS/CFT compliance. Conditions of quasiparticle excitation existence were defined. Non-Fermi liquid parameters impact on the shape of few cycle pulses were estimated. It was shown that extremely short optical pulse propagation in the non-Fermi liquid is a stable pattern. The value of chemical potential has a significant impact on extremely short pulse shape. An increase in initial pulse amplitude does not result in pulse-shape distortions under its propagation in considered medium that is why the non-Fermi liquid can be used in applications inherent in extremely short pulse processing.

  16. Moving in extreme environments: what's extreme and who decides?

    Science.gov (United States)

    Cotter, James David; Tipton, Michael J

    2014-01-01

    , extreme loading, chronic unloading and high altitude. Ramifications include factors such as health and safety, productivity, enjoyment and autonomy, acute and chronic protection and optimising adaptation.

  17. Plasmonic nanocomposite thin film enabled fiber optic sensors for simultaneous gas and temperature sensing at extreme temperatures.

    Science.gov (United States)

    Ohodnicki, Paul R; Buric, Michael P; Brown, Thomas D; Matranga, Christopher; Wang, Congjun; Baltrus, John; Andio, Mark

    2013-10-07

    Embedded sensors capable of operation in extreme environments including high temperatures, high pressures, and highly reducing, oxidizing and/or corrosive environments can make a significant impact on enhanced efficiencies and reduced greenhouse gas emissions of current and future fossil-based power generation systems. Relevant technologies can also be leveraged in a wide range of other applications with similar needs including nuclear power generation, industrial process monitoring and control, and aviation/aerospace. Here we describe a novel approach to embedded sensing under extreme temperature conditions by integration of Au-nanoparticle based plasmonic nanocomposite thin films with optical fibers in an evanescent wave absorption spectroscopy configuration. Such sensors can potentially enable simultaneous temperature and gas sensing at temperatures approaching 900-1000 °C in a manner compatible with embedded and distributed sensing approaches. The approach is demonstrated using the Au/SiO2 system deposited on silica-based optical fibers. Stability of optical fibers under relevant high temperature conditions and interactions with changing ambient gas atmospheres is an area requiring additional investigation and development but the simplicity of the sensor design makes it potentially cost-effective and may offer a potential for widespread deployment.

  18. Assessment of extreme hydrological conditions in the Bothnian Bay, Baltic Sea, and the impact of the nuclear power plant "Hanhikivi-1" on the local thermal regime

    Science.gov (United States)

    Dvornikov, Anton Y.; Martyanov, Stanislav D.; Ryabchenko, Vladimir A.; Eremina, Tatjana R.; Isaev, Alexey V.; Sein, Dmitry V.

    2017-04-01

    The results of the study aimed to assess the influence of future nuclear power plant Hanhikivi-1 upon the local thermal conditions in the Bothnian Bay in the Baltic Sea are presented. A number of experiments with different numerical models were also carried out in order to estimate the extreme hydro-meteorological conditions in the area of the construction. The numerical experiments were fulfilled both with analytically specified external forcing and with real external forcing for 2 years: a cold year (2010) and a warm year (2014). The study has shown that the extreme values of sea level and water temperature and the characteristics of wind waves and sea ice in the vicinity of the future nuclear power plant can be significant and sometimes catastrophic. Permanent release of heat into the marine environment from an operating nuclear power plant will lead to a strong increase in temperature and the disappearance of ice cover within a 2 km vicinity of the station. These effects should be taken into account when assessing local climate changes in the future.

  19. Silicon-Carbide Power MOSFET Performance in High Efficiency Boost Power Processing Unit for Extreme Environments

    Science.gov (United States)

    Ikpe, Stanley A.; Lauenstein, Jean-Marie; Carr, Gregory A.; Hunter, Don; Ludwig, Lawrence L.; Wood, William; Del Castillo, Linda Y.; Fitzpatrick, Fred; Chen, Yuan

    2016-01-01

    Silicon-Carbide device technology has generated much interest in recent years. With superior thermal performance, power ratings and potential switching frequencies over its Silicon counterpart, Silicon-Carbide offers a greater possibility for high powered switching applications in extreme environment. In particular, Silicon-Carbide Metal-Oxide- Semiconductor Field-Effect Transistors' (MOSFETs) maturing process technology has produced a plethora of commercially available power dense, low on-state resistance devices capable of switching at high frequencies. A novel hard-switched power processing unit (PPU) is implemented utilizing Silicon-Carbide power devices. Accelerated life data is captured and assessed in conjunction with a damage accumulation model of gate oxide and drain-source junction lifetime to evaluate potential system performance at high temperature environments.

  20. Accuracy of Handheld Blood Glucose Meters at High Altitude

    NARCIS (Netherlands)

    de Mol, Pieter; Krabbe, Hans G.; de Vries, Suzanna T.; Fokkert, Marion J.; Dikkeschei, Bert D.; Rienks, Rienk; Bilo, Karin M.; Bilo, Henk J. G.

    2010-01-01

    Background: Due to increasing numbers of people with diabetes taking part in extreme sports (e. g., high-altitude trekking), reliable handheld blood glucose meters (BGMs) are necessary. Accurate blood glucose measurement under extreme conditions is paramount for safe recreation at altitude. Prior

  1. Beyond Extreme Ultra Violet (BEUV) Radiation from Spherically symmetrical High-Z plasmas

    Science.gov (United States)

    Yoshida, Kensuke; Fujioka, Shinsuke; Higashiguchi, Takeshi; Ugomori, Teruyuki; Tanaka, Nozomi; Kawasaki, Masato; Suzuki, Yuhei; Suzuki, Chihiro; Tomita, Kentaro; Hirose, Ryouichi; Eshima, Takeo; Ohashi, Hayato; Nishikino, Masaharu; Scally, Enda; Nshimura, Hiroaki; Azechi, Hiroshi; O'Sullivan, Gerard

    2016-03-01

    Photo-lithography is a key technology for volume manufacture of high performance and compact semiconductor devices. Smaller and more complex structures can be fabricated by using shorter wavelength light in the photolithography. One of the most critical issues in development of the next generation photo-lithography is to increase energy conversion efficiency (CE) from laser to shorter wavelength light. Experimental database of beyond extreme ultraviolet (BEUV) radiation was obtained by using spherically symmetrical high-Z plasmas generated with spherically allocated laser beams. Absolute energy and spectra of BEUV light emitted from Tb, Gd, and Mo plasmas were measured with a absolutely calibrated BEUV calorimeter and a transmission grating spectrometer. 1.0 x 1012 W/cm2 is the optimal laser intensity to produced efficient BEUV light source plasmas with Tb and Gd targets. Maximum CE is achieved at 0.8% that is two times higher than the published CEs obtained with planar targets.

  2. Life at the limits: peculiar features of lichen symbiosis related to extreme environmental factors

    Science.gov (United States)

    de Vera, J.-P.; Horneck, G.; Rettberg, P.; Ott, S.

    A lichen is a symbiotic association formed by a mycobiont (fungi), a photobiont (algae) and/or a cyanobacteria. The special symbiotic contact and interaction between the bionts in a lichen is a prerequisite for maintainance of viability for each of them during influences by harsh environmental factors. In nature parameters like UV radiation, low or high temperatures and dryness may have a destructive impact on all life functions of an organism. But with lichens the evolution has created a peculiar symbiosis which enables a wide variety of lichen species to colonize habitats where their separate bionts would not be able to survive. The results of our investigations are demonstrating these aspects (de Vera et al. 2003, 2004).We have already investigated the viability of the entire lichen thallus, the embedded spores in lichen apothecia (fruiting bodies) as well as the isolated spores and isolated photobionts after exposure to most extreme conditions caused by simulated space parameters as extreme UV radiation and vacuum. The results presented here focuse on the survival capacity of the isolated photobionts from the two lichen species Xanthoria elegans and Fulgensia bracteata which are not protected by the fungal structure of the lichen thallus. They are based on examinations using a Confocal Laser Scanning Microscopy (CLSM), analysed by modern methods of the Image Tool Program and by culture experiments. In contrast to photobionts embedded in the entire lichen thallus the isolated photobionts are much more sensitve to the extreme conditions of UV radiation and vaccum: while 50 % of the bionts in an entire lichen thallus are able to cope with simulated extreme space conditions (UV-radiation: λ quad ≥ 160nm and vacuum: p = 10-5 Pa) during an exposure time of 2 weeks, the viability of the isolated photobiont cells was already decreasing after 2 hours of exposure. All photobiont cells were inactivated after longer exposure times of about 8 hours. Further more analysis

  3. AN EXTREMELY CARBON-RICH, EXTREMELY METAL-POOR STAR IN THE SEGUE 1 SYSTEM

    International Nuclear Information System (INIS)

    Norris, John E.; Yong, David; Gilmore, Gerard; Wyse, Rosemary F. G.; Frebel, Anna

    2010-01-01

    We report the analysis of high-resolution, high signal-to-noise ratio, spectra of an extremely metal-poor, extremely C-rich red giant, Seg 1-7, in Segue 1-described in the literature alternatively as an unusually extended globular cluster or an ultra-faint dwarf galaxy. The radial velocity of Seg 1-7 coincides precisely with the systemic velocity of Segue 1, and its chemical abundance signature of [Fe/H] = -3.52, [C/Fe] = +2.3, [N/Fe] = +0.8, [Na/Fe] = +0.53, [Mg/Fe] = +0.94, [Al/Fe] = +0.23, and [Ba/Fe] < -1.0 is similar to that of the rare and enigmatic class of Galactic halo objects designated CEMP-no (carbon-rich, extremely metal-poor with no enhancement (over solar ratios) of heavy neutron-capture elements). This is the first star in a Milky Way 'satellite' that unambiguously lies on the metal-poor, C-rich branch of the Aoki et al. bimodal distribution of field halo stars in the ([C/Fe], [Fe/H])-plane. Available data permit us only to identify Seg 1-7 as a member of an ultra-faint dwarf galaxy or as debris from the Sgr dwarf spheroidal galaxy. In either case, this demonstrates that at extremely low abundance, [Fe/H ] <-3.0, star formation and associated chemical evolution proceeded similarly in the progenitors of both the field halo and satellite systems. By extension, this is consistent with other recent suggestions that the most metal-poor dwarf spheroidal and ultra-faint dwarf satellites were the building blocks of the Galaxy's outer halo.

  4. Convergence of Extreme Value Statistics in a Two-Layer Quasi-Geostrophic Atmospheric Model

    Directory of Open Access Journals (Sweden)

    Vera Melinda Gálfi

    2017-01-01

    Full Text Available We search for the signature of universal properties of extreme events, theoretically predicted for Axiom A flows, in a chaotic and high-dimensional dynamical system. We study the convergence of GEV (Generalized Extreme Value and GP (Generalized Pareto shape parameter estimates to the theoretical value, which is expressed in terms of the partial information dimensions of the attractor. We consider a two-layer quasi-geostrophic atmospheric model of the mid-latitudes, adopt two levels of forcing, and analyse the extremes of different types of physical observables (local energy, zonally averaged energy, and globally averaged energy. We find good agreement in the shape parameter estimates with the theory only in the case of more intense forcing, corresponding to a strong chaotic behaviour, for some observables (the local energy at every latitude. Due to the limited (though very large data size and to the presence of serial correlations, it is difficult to obtain robust statistics of extremes in the case of the other observables. In the case of weak forcing, which leads to weaker chaotic conditions with regime behaviour, we find, unsurprisingly, worse agreement with the theory developed for Axiom A flows.

  5. Global predictability of temperature extremes

    Science.gov (United States)

    Coughlan de Perez, Erin; van Aalst, Maarten; Bischiniotis, Konstantinos; Mason, Simon; Nissan, Hannah; Pappenberger, Florian; Stephens, Elisabeth; Zsoter, Ervin; van den Hurk, Bart

    2018-05-01

    Extreme temperatures are one of the leading causes of death and disease in both developed and developing countries, and heat extremes are projected to rise in many regions. To reduce risk, heatwave plans and cold weather plans have been effectively implemented around the world. However, much of the world’s population is not yet protected by such systems, including many data-scarce but also highly vulnerable regions. In this study, we assess at a global level where such systems have the potential to be effective at reducing risk from temperature extremes, characterizing (1) long-term average occurrence of heatwaves and coldwaves, (2) seasonality of these extremes, and (3) short-term predictability of these extreme events three to ten days in advance. Using both the NOAA and ECMWF weather forecast models, we develop global maps indicating a first approximation of the locations that are likely to benefit from the development of seasonal preparedness plans and/or short-term early warning systems for extreme temperature. The extratropics generally show both short-term skill as well as strong seasonality; in the tropics, most locations do also demonstrate one or both. In fact, almost 5 billion people live in regions that have seasonality and predictability of heatwaves and/or coldwaves. Climate adaptation investments in these regions can take advantage of seasonality and predictability to reduce risks to vulnerable populations.

  6. [The effects of electromagnetic radiation of extremely high frequency and low intensity on the growth rate of bacteria Escherichia coli and the role of medium pH].

    Science.gov (United States)

    Tadevosian, A; Kalantarian, V; Trchunian, A

    2007-01-01

    It has been shown that coherent electromagnetic irradiation (EMI) of extremely high frequency (45-53 GHz) or millimeter waves (wavelength 5.6-6.7 mm) of low intensity (flux capacity 0.06 mW/cm2) of Escherichia coli K12, grown under anaerobic conditions during the fermentation of sugar (glucose) for 30 min or 1 h, caused a decrease in their growth rate, the maximum inhibitory effect being achieved at a frequency of 51.8 or 53 GHz. This effect depended on medium pH when the maximal action was determined at pH 7.5. In addition, separate 30-min of 1-h irradiation (frequency 51.8 or 53 GHz) of doubly distilled water or some inorganic ions contained in Tris-phosphate buffer where the cells were transferred induced oppositely directed changes in further growth of these bacteria under anaerobic conditions; irradiation of water caused a decrease in the growth rate of bacteria. A significant change in pH of water (0.5-1.5 unit) was induced by a 30-irradiation at a frequency of 49, 50.3, 51.8, or 53 GHz, when the initial pH value was 6.0 or 8.0, but not 7.5. These results indicate the changes in the properties of water and its role in the effects of EMI of extremely high frequency. The marked effect of EMI on bacteria disappeared upon repeated irradiation for 1 h at a frequency of 51.8 or 53 GHz with an interval of 2 hours. This result indicates some compensatory mechanisms in bacteria.

  7. Handling and storage of conditioned high-level wastes

    International Nuclear Information System (INIS)

    1983-01-01

    This report deals with certain aspects of the management of one of the most important wastes, i.e. the handling and storage of conditioned (immobilized and packaged) high-level waste from the reprocessing of spent nuclear fuel and, although much of the material presented here is based on information concerning high-level waste from reprocessing LWR fuel, the principles, as well as many of the details involved, are applicable to all fuel types. The report provides illustrative background material on the arising and characteristics of high-level wastes and, qualitatively, their requirements for conditioning. The report introduces the principles important in conditioned high-level waste storage and describes the types of equipment and facilities, used or studied, for handling and storage of such waste. Finally, it discusses the safety and economic aspects that are considered in the design and operation of handling and storage facilities

  8. Handling and storage of conditioned high-level wastes

    International Nuclear Information System (INIS)

    Heafield, W.

    1984-01-01

    This paper deals with certain aspects of the management of one of the most important radioactive wastes arising from the nuclear fuel cycle, i.e. the handling and storage of conditioned high-level wastes. The paper is based on an IAEA report of the same title published during 1983 in the Technical Reports Series. The paper provides illustrative background material on the characteristics of high-level wastes and, qualitatively, their requirements for conditioning. The principles important in the storage of high-level wastes are reviewed in conjunction with the radiological and socio-political considerations involved. Four fundamentally different storage concepts are described with reference to published information and the safety aspects of particular storage concepts are discussed. Finally, overall conclusions are presented which confirm the availability of technology for constructing and operating conditioned high-level waste storage facilities for periods of at least several decades. (author)

  9. Performance and biocompatibility of extremely tough alginate/polyacrylamide hydrogels.

    Science.gov (United States)

    Darnell, Max C; Sun, Jeong-Yun; Mehta, Manav; Johnson, Christopher; Arany, Praveen R; Suo, Zhigang; Mooney, David J

    2013-11-01

    Although hydrogels now see widespread use in a host of applications, low fracture toughness and brittleness have limited their more broad use. As a recently described interpenetrating network (IPN) of alginate and polyacrylamide demonstrated a fracture toughness of ≈ 9000 J/m(2), we sought to explore the biocompatibility and maintenance of mechanical properties of these hydrogels in cell culture and in vivo conditions. These hydrogels can sustain a compressive strain of over 90% with minimal loss of Young's Modulus as well as minimal swelling for up to 50 days of soaking in culture conditions. Mouse mesenchymal stem cells exposed to the IPN gel-conditioned media maintain high viability, and although cells exposed to conditioned media demonstrate slight reductions in proliferation and metabolic activity (WST assay), these effects are abrogated in a dose-dependent manner. Implantation of these IPN hydrogels into subcutaneous tissue of rats for 8 weeks led to mild fibrotic encapsulation and minimal inflammatory response. These results suggest the further exploration of extremely tough alginate/PAAM IPN hydrogels as biomaterials. © 2013 Elsevier Ltd. All rights reserved.

  10. Risk from drought and extreme heat in Russian wheat production and its relation to atmospheric blocking and teleconnection patterns

    Science.gov (United States)

    Giannakaki, Paraskevi; Calanca, Pierluigi

    2017-04-01

    Russia has become one of the leading wheat exporters worldwide. Major breakdowns in Russian wheat production induced by extreme weather events are therefore of high significance not only for the domestic but also for the global market. Wheat production in south-western Russia, the main growing area, suffers in particular from the adverse effects of drought and heat waves. For this reason knowledge of the occurrence of this type of extreme events and of the processes that lead to adverse conditions is of paramount importance for risk management. The negative impacts of heat waves and drought are particularly severe when anomalous conditions persist in time. As an example, a blocking event in summer 2010 resulted in one of the warmest and worst drought conditions in Russia's recent history. The latter caused a decline in Russian wheat production by more than 30%, which in turn prompted the Russian government to issue an export ban that lasted until summer 2011. In view of this, the question of course arises of how much of the negative variations in Russian wheat production levels can be explained by blocking events and other features of the large-scale atmospheric circulation. Specific questions are: how often are blocking events over Russia associated with extreme high temperatures and dry conditions? Which of the teleconnection patterns are correlated with drought and heat stress conditions in the area? Answering these questions can contribute to a develop strategies for agricultural risk management. In this contribution we present results of a study that aims at characterizing the occurrence of adverse weather conditions in south-western Russia in relation to atmospheric blocking and teleconnection patterns such as East Atlantic/Western Russia pattern, the Polar/Eurasia pattern, the North Atlantic Oscillation and the Scandinavia pattern. The analysis relies on weather data for 1980-2014 from 130 stations distributed across the wheat production area. The account

  11. Assessment of some high-order finite difference schemes on the scalar conservation law with periodical conditions

    Directory of Open Access Journals (Sweden)

    Alina BOGOI

    2016-12-01

    Full Text Available Supersonic/hypersonic flows with strong shocks need special treatment in Computational Fluid Dynamics (CFD in order to accurately capture the discontinuity location and his magnitude. To avoid numerical instabilities in the presence of discontinuities, the numerical schemes must generate low dissipation and low dispersion error. Consequently, the algorithms used to calculate the time and space-derivatives, should exhibit a low amplitude and phase error. This paper focuses on the comparison of the numerical results obtained by simulations with some high resolution numerical schemes applied on linear and non-linear one-dimensional conservation low. The analytical solutions are provided for all benchmark tests considering smooth periodical conditions. All the schemes converge to the proper weak solution for linear flux and smooth initial conditions. However, when the flux is non-linear, the discontinuities may develop from smooth initial conditions and the shock must be correctly captured. All the schemes accurately identify the shock position, with the price of the numerical oscillation in the vicinity of the sudden variation. We believe that the identification of this pure numerical behavior, without physical relevance, in 1D case is extremely useful to avoid problems related to the stability and convergence of the solution in the general 3D case.

  12. Are extreme hydro-meteorological events a prerequisite for extreme water quality impacts? Exploring climate impacts on inland and coastal waters

    Science.gov (United States)

    Michalak, A. M.; Balaji, V.; Del Giudice, D.; Sinha, E.; Zhou, Y.; Ho, J. C.

    2017-12-01

    Questions surrounding water sustainability, climate change, and extreme events are often framed around water quantity - whether too much or too little. The massive impacts of extreme water quality impairments are equally compelling, however. Recent years have provided a host of compelling examples, with unprecedented harmful algal blooms developing along the West coast, in Utah Lake, in Lake Erie, and off the Florida coast, and huge hypoxic dead zones continuing to form in regions such as Lake Erie, the Chesapeake Bay, and the Gulf of Mexico. Linkages between climate change, extreme events, and water quality impacts are not well understood, however. Several factors explain this lack of understanding, including the relative complexity of underlying processes, the spatial and temporal scale mismatch between hydrologists and climatologists, and observational uncertainty leading to ambiguities in the historical record. Here, we draw on a number of recent studies that aim to quantitatively link meteorological variability and water quality impacts to test the hypothesis that extreme water quality impairments are the result of extreme hydro-meteorological events. We find that extreme hydro-meteorological events are neither always a necessary nor a sufficient condition for the occurrence of extreme water quality impacts. Rather, extreme water quality impairments often occur in situations where multiple contributing factors compound, which complicates both attribution of historical events and the ability to predict the future incidence of such events. Given the critical societal importance of water quality projections, a concerted program of uncertainty reduction encompassing observational and modeling components will be needed to examine situations where extreme weather plays an important, but not solitary, role in the chain of cause and effect.

  13. Risk assessment of precipitation extremes in northern Xinjiang, China

    Science.gov (United States)

    Yang, Jun; Pei, Ying; Zhang, Yanwei; Ge, Quansheng

    2018-05-01

    This study was conducted using daily precipitation records gathered at 37 meteorological stations in northern Xinjiang, China, from 1961 to 2010. We used the extreme value theory model, generalized extreme value (GEV) and generalized Pareto distribution (GPD), statistical distribution function to fit outputs of precipitation extremes with different return periods to estimate risks of precipitation extremes and diagnose aridity-humidity environmental variation and corresponding spatial patterns in northern Xinjiang. Spatiotemporal patterns of daily maximum precipitation showed that aridity-humidity conditions of northern Xinjiang could be well represented by the return periods of the precipitation data. Indices of daily maximum precipitation were effective in the prediction of floods in the study area. By analyzing future projections of daily maximum precipitation (2, 5, 10, 30, 50, and 100 years), we conclude that the flood risk will gradually increase in northern Xinjiang. GEV extreme value modeling yielded the best results, proving to be extremely valuable. Through example analysis for extreme precipitation models, the GEV statistical model was superior in terms of favorable analog extreme precipitation. The GPD model calculation results reflect annual precipitation. For most of the estimated sites' 2 and 5-year T for precipitation levels, GPD results were slightly greater than GEV results. The study found that extreme precipitation reaching a certain limit value level will cause a flood disaster. Therefore, predicting future extreme precipitation may aid warnings of flood disaster. A suitable policy concerning effective water resource management is thus urgently required.

  14. Characterization of extremely low frequency magnetic fields from diesel, gasoline and hybrid cars under controlled conditions.

    Science.gov (United States)

    Hareuveny, Ronen; Sudan, Madhuri; Halgamuge, Malka N; Yaffe, Yoav; Tzabari, Yuval; Namir, Daniel; Kheifets, Leeka

    2015-01-30

    This study characterizes extremely low frequency (ELF) magnetic field (MF) levels in 10 car models. Extensive measurements were conducted in three diesel, four gasoline, and three hybrid cars, under similar controlled conditions and negligible background fields. Averaged over all four seats under various driving scenarios the fields were lowest in diesel cars (0.02 μT), higher for gasoline (0.04-0.05 μT) and highest in hybrids (0.06-0.09 μT), but all were in-line with daily exposures from other sources. Hybrid cars had the highest mean and 95th percentile MF levels, and an especially large percentage of measurements above 0.2 μT. These parameters were also higher for moving conditions compared to standing while idling or revving at 2500 RPM and higher still at 80 km/h compared to 40 km/h. Fields in non-hybrid cars were higher at the front seats, while in hybrid cars they were higher at the back seats, particularly the back right seat where 16%-69% of measurements were greater than 0.2 μT. As our results do not include low frequency fields (below 30 Hz) that might be generated by tire rotation, we suggest that net currents flowing through the cars' metallic chassis may be a possible source of MF. Larger surveys in standardized and well-described settings should be conducted with different types of vehicles and with spectral analysis of fields including lower frequencies due to magnetization of tires.

  15. High energy x-ray and neutron studies of disordered energy-related materials at extreme conditions

    International Nuclear Information System (INIS)

    Parise, John

    2016-01-01

    The fundamental scientific accomplishments are: (1) advances in a general description of the liquid state by employing structural models constrained by measurements to interpret experimental results and extend them to liquids in general, with special emphasis on (2) The structure of the high-temperature crystal and molten UO_2 and 3) water. Specifically, samples of UO_2 and water were probed using high-energy x-rays at the Advanced Photon Source. The high Z of UO_2, and the 2-3mm diameter droplet shape of the molten sample, means that >100keV X-rays are required to minimize absorption and multiple scattering, which can distort the measured structure factor. A high flux of x-rays is also required to obtain sufficient statistical accuracy in short (a few seconds) measurement times. The scattered x-ray data were analyzed and pair distribution functions, extracted that characterize the local and long-range atomic structure of the material. The measurements of the hot UO_2 solid show a substantial increase in oxygen disorder and, upon melting, the average U-O coordination was found to decrease from 8 to 6.7±0.5. The research incorporated development of diffraction techniques, sample environment optimization and state-of-the-art simulation techniques. The symbiotic nature of the advances in simulation and experiment allowed for a more focused and informed development of future experiments, effective use of expensive beam time and generated new research agendas for the growing number of research groups, within the US and internationally, that focus on the structure of liquids. Molecular dynamics (MD) provided detailed information when combined with high-quality XN data including addressing key issues in liquids; the relationship between cooling path, structure and fictive temperature, and the trade-offs between network over connectedness in liquids containing low-coordination cations.

  16. High energy x-ray and neutron studies of disordered energy-related materials at extreme conditions

    Energy Technology Data Exchange (ETDEWEB)

    Parise, John [Stony Brook Univ., NY (United States)

    2016-05-16

    The fundamental scientific accomplishments are: (1) advances in a general description of the liquid state by employing structural models constrained by measurements to interpret experimental results and extend them to liquids in general, with special emphasis on (2) The structure of the high-temperature crystal and molten UO2 and 3) water. Specifically, samples of UO2 and water were probed using high-energy x-rays at the Advanced Photon Source. The high Z of UO2, and the 2-3mm diameter droplet shape of the molten sample, means that >100keV X-rays are required to minimize absorption and multiple scattering, which can distort the measured structure factor. A high flux of x-rays is also required to obtain sufficient statistical accuracy in short (a few seconds) measurement times. The scattered x-ray data were analyzed and pair distribution functions, extracted that characterize the local and long-range atomic structure of the material. The measurements of the hot UO2 solid show a substantial increase in oxygen disorder and, upon melting, the average U-O coordination was found to decrease from 8 to 6.7±0.5. The research incorporated development of diffraction techniques, sample environment optimization and state-of-the-art simulation techniques. The symbiotic nature of the advances in simulation and experiment allowed for a more focused and informed development of future experiments, effective use of expensive beam time and generated new research agendas for the growing number of research groups, within the US and internationally, that focus on the structure of liquids. Molecular dynamics (MD) provided detailed information when combined with high-quality XN data including addressing key issues in liquids; the relationship between cooling path, structure and fictive temperature, and the trade-offs between network over connectedness in liquids containing low-coordination cations.

  17. Probabilistic attribution of individual unprecedented extreme events

    Science.gov (United States)

    Diffenbaugh, N. S.

    2016-12-01

    The last decade has seen a rapid increase in efforts to understand the influence of global warming on individual extreme climate events. Although trends in the distributions of climate observations have been thoroughly analyzed, rigorously quantifying the contribution of global-scale warming to individual events that are unprecedented in the observed record presents a particular challenge. This paper describes a method for leveraging observations and climate model ensembles to quantify the influence of historical global warming on the severity and probability of unprecedented events. This approach uses formal inferential techniques to quantify four metrics: (1) the contribution of the observed trend to the event magnitude, (2) the contribution of the observed trend to the event probability, (3) the probability of the observed trend in the current climate and a climate without human influence, and (4) the probability of the event magnitude in the current climate and a climate without human influence. Illustrative examples are presented, spanning a range of climate variables, timescales, and regions. These examples illustrate that global warming can influence the severity and probability of unprecedented extremes. In some cases - particularly high temperatures - this change is indicated by changes in the mean. However, changes in probability do not always arise from changes in the mean, suggesting that global warming can alter the frequency with which complex physical conditions co-occur. Because our framework is transparent and highly generalized, it can be readily applied to a range of climate events, regions, and levels of climate forcing.

  18. SPREAD: a high-resolution daily gridded precipitation dataset for Spain – an extreme events frequency and intensity overview

    Directory of Open Access Journals (Sweden)

    R. Serrano-Notivoli

    2017-09-01

    Full Text Available A high-resolution daily gridded precipitation dataset was built from raw data of 12 858 observatories covering a period from 1950 to 2012 in peninsular Spain and 1971 to 2012 in Balearic and Canary islands. The original data were quality-controlled and gaps were filled on each day and location independently. Using the serially complete dataset, a grid with a 5 × 5 km spatial resolution was constructed by estimating daily precipitation amounts and their corresponding uncertainty at each grid node. Daily precipitation estimations were compared to original observations to assess the quality of the gridded dataset. Four daily precipitation indices were computed to characterise the spatial distribution of daily precipitation and nine extreme precipitation indices were used to describe the frequency and intensity of extreme precipitation events. The Mediterranean coast and the Central Range showed the highest frequency and intensity of extreme events, while the number of wet days and dry and wet spells followed a north-west to south-east gradient in peninsular Spain, from high to low values in the number of wet days and wet spells and reverse in dry spells. The use of the total available data in Spain, the independent estimation of precipitation for each day and the high spatial resolution of the grid allowed for a precise spatial and temporal assessment of daily precipitation that is difficult to achieve when using other methods, pre-selected long-term stations or global gridded datasets. SPREAD dataset is publicly available at https://doi.org/10.20350/digitalCSIC/7393.

  19. Jump conditions in transonic equilibria

    International Nuclear Information System (INIS)

    Guazzotto, L.; Betti, R.; Jardin, S. C.

    2013-01-01

    In the present paper, the numerical calculation of transonic equilibria, first introduced with the FLOW code in Guazzotto et al.[Phys. Plasmas 11, 604 (2004)], is critically reviewed. In particular, the necessity and effect of imposing explicit jump conditions at the transonic discontinuity are investigated. It is found that “standard” (low-β, large aspect ratio) transonic equilibria satisfy the correct jump condition with very good approximation even if the jump condition is not explicitly imposed. On the other hand, it is also found that high-β, low aspect ratio equilibria require the correct jump condition to be explicitly imposed. Various numerical approaches are described to modify FLOW to include the jump condition. It is proved that the new methods converge to the correct solution even in extreme cases of very large β, while they agree with the results obtained with the old implementation of FLOW in lower-β equilibria.

  20. Sediment Dynamics Within Buffer Zone and Sinkhole Splay Areas Under Extreme Soil Disturbance Conditions.

    Science.gov (United States)

    Schoonover, Jon E; Crim, Jackie F; Williard, Karl W J; Groninger, John W; Zaczek, James J; Pattumma, Klairoong

    2015-09-01

    Sedimentation dynamics were assessed in sinkholes within training areas at Ft. Knox Military Installation, a karst landscape subjected to decades of tracked vehicle use and extreme soil disturbance. Sinkholes sampled were sediment-laden and behaved as intermittent ponds. Dendrogeomorphic analyses were conducted using willow trees (Salix spp.) located around the edge of 18 sinkholes to estimate historical sedimentation rates, and buried bottles were installed in 20 sinkholes at the center, outer edge, and at the midpoint between the center and edge to estimate annual sedimentation rates. Sedimentation data were coupled with vegetation characteristics of sinkhole buffers to determine relationships among these variables. The dendrogeomorphic method estimated an average accumulation rate of 1.27 cm year(-1) translating to a sediment loss rate of 46.1 metric ton year(-1) from the training areas. However, sediment export to sinkholes was estimated to be much greater (118.6 metric ton year(-1)) via the bottle method. These data suggest that the latter method provided a more accurate estimate since accumulation was greater in the center of sinkholes compared to the periphery where dendrogeomorphic data were collected. Vegetation data were not tightly correlated with sedimentation rates, suggesting that further research is needed to identify a viable proxy for direct measures of sediment accumulation in this extreme deposition environment. Mitigation activities for the sinkholes at Ft. Knox's tank training area, and other heavily disturbed karst environments where extreme sedimentation exists, should consider focusing on flow path and splay area management.

  1. A new class of photoactivatable and carbene generating reagents with extremely high specific radioactivity. Synthesis, characterization and applications

    International Nuclear Information System (INIS)

    Weber, T.

    1994-01-01

    The main objective of this work was the development of new photocrosslinking and labeling reagents which show favourable photochemical properties and can be synthesized in an extremely high specific radioactivity. A key compound in the synthesis of these reagents was 2-tributyltin-4-(3-trifluormethyl-3H-diazirin-3-yl)-benzyl alcohol. Esters of this alcohol can be easily radioiodinated at a specific radioactivity of >2000 Ci/mmol under mild conditions. By experiments with a model compound it was shown that 2-iodo-4-(3-trifluormethyl-3H-diazirin-3-yl)-benzyl esters, upon photolysis, generate highly reactive (singlet) carbenes capable of inserting into CH-bonds. Equally important, there is no indication of loss of iodine under the photolysis conditions applied. Therefore two key requirements for photolabeling reagents are fulfilled. Several photoactivatable radioiodinated phospholipids have been synthesized. Their properties have been evaluated by labeling of the the membranes of intact erythrocytes and influenza viruses. Currently these lipids are used to study the interaction of various proteins (shown are experiments with MARCKS) with membranes. Furthermore a new class of actual label transfer crosslinkers (two thiol specific and one amino specific) have been developed. The range of potentialities of these reagents is currently being investigated. Finally a photoactivatable radioiodinated ceramide analogue suitable as a photoaffinity crosslinker has been developed with the goal of identifying the putative receptor of this second messenger-like lipid. Preliminary studies towards this goal are described. We are convinced that the reagents and methods presented in this work are valuable tools, and that they will find widespread use in future cell-biological and biochemical research. (author) figs., tabs., refs

  2. Consortium for Health and Military Performance and American College of Sports Medicine consensus paper on extreme conditioning programs in military personnel.

    Science.gov (United States)

    Bergeron, Michael F; Nindl, Bradley C; Deuster, Patricia A; Baumgartner, Neal; Kane, Shawn F; Kraemer, William J; Sexauer, Lisa R; Thompson, Walter R; O'Connor, Francis G

    2011-01-01

    A potential emerging problem associated with increasingly popularized extreme conditioning programs (ECPs) has been identified by the military and civilian communities. That is, there is an apparent disproportionate musculoskeletal injury risk from these demanding programs, particularly for novice participants, resulting in lost duty time, medical treatment, and extensive rehabilitation. This is a significant and costly concern for the military with regard to effectively maintaining operational readiness of the Force. While there are certain recognized positive aspects of ECPs that address a perceived and/or actual unfulfilled conditioning need for many individuals and military units, these programs have limitations and should be considered carefully. Moreover, certain distinctive characteristics of ECPs appear to violate recognized accepted standards for safely and appropriately developing muscular fitness and are not uniformly aligned with established and accepted training doctrine. Accordingly, practical solutions to improve ECP prescription and implementation and reduce injury risk are of paramount importance.

  3. Feasibility of performing high resolution cloud-resolving simulations of historic extreme events: The San Fruttuoso (Liguria, italy) case of 1915.

    Science.gov (United States)

    Parodi, Antonio; Boni, Giorgio; Ferraris, Luca; Gallus, William; Maugeri, Maurizio; Molini, Luca; Siccardi, Franco

    2017-04-01

    Recent studies show that highly localized and persistent back-building mesoscale convective systems represent one of the most dangerous flash-flood producing storms in the north-western Mediterranean area. Substantial warming of the Mediterranean Sea in recent decades raises concerns over possible increases in frequency or intensity of these types of events as increased atmospheric temperatures generally support increases in water vapor content. Analyses of available historical records do not provide a univocal answer, since these may be likely affected by a lack of detailed observations for older events. In the present study, 20th Century Reanalysis Project initial and boundary condition data in ensemble mode are used to address the feasibility of performing cloud-resolving simulations with 1 km horizontal grid spacing of a historic extreme event that occurred over Liguria (Italy): The San Fruttuoso case of 1915. The proposed approach focuses on the ensemble Weather Research and Forecasting (WRF) model runs, as they are the ones most likely to best simulate the event. It is found that these WRF runs generally do show wind and precipitation fields that are consistent with the occurrence of highly localized and persistent back-building mesoscale convective systems, although precipitation peak amounts are underestimated. Systematic small north-westward position errors with regard to the heaviest rain and strongest convergence areas imply that the Reanalysis members may not be adequately representing the amount of cool air over the Po Plain outflowing into the Liguria Sea through the Apennines gap. Regarding the role of historical data sources, this study shows that in addition to Reanalysis products, unconventional data, such as historical meteorological bulletins, newspapers and even photographs can be very valuable sources of knowledge in the reconstruction of past extreme events.

  4. Combined effects of extremely high frequency electromagnetic field and antibiotics on Enterococcus Hirae growth and survival

    International Nuclear Information System (INIS)

    Ohanyan, V.A.

    2012-01-01

    Combined effects of extremely high frequency electromagnetic field and antibiotics on Enterococcus hirae ATCC 9790 bacterial growth and survival were investigated using 51.8 GHz and 53 GHz frequencies in combination with two commonly used antibiotics: ampicillin and dalacin. Results revealed that, despite bacterial type and membrane structure and properties, the combined effect, especially with 53 GHz and dalacin, suppresses bacterial growth and decreases their survival

  5. Torque and power outputs on different subjects during manual wheelchair propulsion under different conditions

    Science.gov (United States)

    Hwang, Seonhong; Kim, Seunghyeon; Son, Jongsang; Kim, Youngho

    2012-02-01

    Manual wheelchair users are at a high risk of pain and injuries to the upper extremities due to mechanical inefficiency of wheelchair propulsion motion. The kinetic analysis of the upper extremities during manual wheelchair propulsion in various conditions needed to be investigated. We developed and calibrated a wheelchair dynamometer for measuring kinetic parameters during propulsion. We utilized the dynamometer to investigate and compare the propulsion torque and power values of experienced and novice users under four different conditions. Experienced wheelchair users generated lower torques with more power than novice users and reacted alertly and sensitively to changing conditions. We expect that these basic methods and results may help to quantitatively evaluate the mechanical efficiency of manual wheelchair propulsion.

  6. Extremely high hole concentrations in c-plane GaN

    Energy Technology Data Exchange (ETDEWEB)

    Trybus, Elaissa; Moseley, Michael; Henderson, Walter; Billingsley, Daniel [Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA (United States); Namkoong, Gon [Old Dominion University, Applied Research Center, Newport News, VA (United States); Look, David C. [Wright State University, Semiconductor Research Center, Dayton, OH (United States); Doolittle, W.A.

    2009-06-15

    Metal Modulated Epitaxy (S. D. Burnham et al., J. Appl. Phys. 104, 024902 (2008)[1]) is extended to include modulation of both the shutters of Ga and Mg, the Mg being delivered from a Veeco corrosive series valved cracker (S. D. Burnham et al., Mater. Res. Soc. Proc. 798, Y8.11 (2003)[2]). The Ga fluxes used are sufficiently large that droplets rapidly form when the Ga shutter opens and are subsequently depleted when the Ga shutter closes. The result is the ability to limit surface faceting while predominantly growing under average N-rich growth conditions and thus, possibly reduce N-vacancy defects. N-vacancy defects are known to result in compensation. This ability to grow higher quality materials under N-rich conditions results in very high hole concentrations and low resistivity p-type materials. Hole concentrations as high as 2 x 10{sup 19} cm{sup -3} have been achieved on c-plane GaN resulting in resistivities as low as 0.38 ohm-cm. The dependence on Ga flux, shutter timing, the corresponding RHEED images for each condition is detailed and clearly show minimization of faceting and crystal quality variations as determined by X-ray diffraction. Quantification of the Mg incorporation and residual impurities such as hydrogen, oxygen, and carbon by SIMS, eliminates co-doping, while temperature dependent hall measurements show reduced activation energies. X-ray diffraction data compares crystalline quality with hole concentration. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Temperature extremes reduce seagrass growth and induce mortality

    International Nuclear Information System (INIS)

    Collier, C.J.; Waycott, M.

    2014-01-01

    Highlights: • Temperature extremes occur during low tide in shallow seagrass meadows. • The effects of temperature extremes were tested experimentally at 35 °C, 40 °C and 43 °C. • 40 °C was a critical threshold with a large impact on growth and mortality. • At 43 °C there was complete mortality after 2–3 days. • Lower light conditions (e.g. poor water quality) led to a greater negative impact. - Abstract: Extreme heating (up to 43 °C measured from five-year temperature records) occurs in shallow coastal seagrass meadows of the Great Barrier Reef at low tide. We measured effective quantum yield (ϕ PSII ), growth, senescence and mortality in four tropical seagrasses to experimental short-duration (2.5 h) spikes in water temperature to 35 °C, 40 °C and 43 °C, for 6 days followed by one day at ambient temperature. Increasing temperature to 35 °C had positive effects on ϕ PSII (the magnitude varied between days and was highly correlated with PPFD), with no effects on growth or mortality. 40 °C represented a critical threshold as there were strong species differences and there was a large impact on growth and mortality. At 43 °C there was complete mortality after 2–3 days. These findings indicate that increasing duration (more days in a row) of thermal events above 40 °C is likely to affect the ecological function of tropical seagrass meadows

  8. Measuring risk of crude oil at extreme quantiles

    Directory of Open Access Journals (Sweden)

    Saša Žiković

    2011-06-01

    Full Text Available The purpose of this paper is to investigate the performance of VaR models at measuring risk for WTI oil one-month futures returns. Risk models, ranging from industry standards such as RiskMetrics and historical simulation to conditional extreme value model, are used to calculate commodity market risk at extreme quantiles: 0.95, 0.99, 0.995 and 0.999 for both long and short trading positions. Our results show that out of the tested fat tailed distributions, generalised Pareto distribution provides the best fit to both tails of oil returns although tails differ significantly, with the right tail having a higher tail index, indicative of more extreme events. The main conclusion is that, in the analysed period, only extreme value theory based models provide a reasonable degree of safety while widespread VaR models do not provide adequate risk coverage and their performance is especially weak for short position in oil.

  9. Frequency Analysis of High Flow Extremes in the Yingluoxia Watershed in Northwest China

    Directory of Open Access Journals (Sweden)

    Zhanling Li

    2016-05-01

    Full Text Available Statistical modeling of hydrological extremes is significant to the construction of hydraulic engineering. This paper, taking the Yingluoxia watershed as the study area, compares the annual maximum (AM series and the peaks over a threshold (POT series in order to study the hydrological extremes, examines the stationarity and independence assumptions for the two series, and discusses the estimations and uncertainties of return levels from the two series using the Generalized Extreme Value (GEV and Generalized Pareto distribution (GPD models. For comparison, the return levels from all threshold excesses with considering the extremal index are also estimated. For the POT series, the threshold is selected by examining the mean excess plot and the stability of the parameter estimates and by using common-sense. The serial correlation is reduced by filtering out a set of dependent threshold excesses. Results show that both series are approximately stationary and independent. The GEV model fits the AM series well and the GPD model fits the POT series well. The estimated return levels are fairly comparable for the AM series, the POT series, and all threshold excesses with considering the extremal index, with the difference being less than 10% for return periods longer than 10 years. The uncertainties of the estimated return levels are the highest for the AM series, and next for the POT series and then for all threshold excesses series in turn.

  10. Adventure and Extreme Sports.

    Science.gov (United States)

    Gomez, Andrew Thomas; Rao, Ashwin

    2016-03-01

    Adventure and extreme sports often involve unpredictable and inhospitable environments, high velocities, and stunts. These activities vary widely and include sports like BASE jumping, snowboarding, kayaking, and surfing. Increasing interest and participation in adventure and extreme sports warrants understanding by clinicians to facilitate prevention, identification, and treatment of injuries unique to each sport. This article covers alpine skiing and snowboarding, skateboarding, surfing, bungee jumping, BASE jumping, and whitewater sports with emphasis on epidemiology, demographics, general injury mechanisms, specific injuries, chronic injuries, fatality data, and prevention. Overall, most injuries are related to overuse, trauma, and environmental or microbial exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Large Scale Meteorological Pattern of Extreme Rainfall in Indonesia

    Science.gov (United States)

    Kuswanto, Heri; Grotjahn, Richard; Rachmi, Arinda; Suhermi, Novri; Oktania, Erma; Wijaya, Yosep

    2014-05-01

    Extreme Weather Events (EWEs) cause negative impacts socially, economically, and environmentally. Considering these facts, forecasting EWEs is crucial work. Indonesia has been identified as being among the countries most vulnerable to the risk of natural disasters, such as floods, heat waves, and droughts. Current forecasting of extreme events in Indonesia is carried out by interpreting synoptic maps for several fields without taking into account the link between the observed events in the 'target' area with remote conditions. This situation may cause misidentification of the event leading to an inaccurate prediction. Grotjahn and Faure (2008) compute composite maps from extreme events (including heat waves and intense rainfall) to help forecasters identify such events in model output. The composite maps show large scale meteorological patterns (LSMP) that occurred during historical EWEs. Some vital information about the EWEs can be acquired from studying such maps, in addition to providing forecaster guidance. Such maps have robust mid-latitude meteorological patterns (for Sacramento and California Central Valley, USA EWEs). We study the performance of the composite approach for tropical weather condition such as Indonesia. Initially, the composite maps are developed to identify and forecast the extreme weather events in Indramayu district- West Java, the main producer of rice in Indonesia and contributes to about 60% of the national total rice production. Studying extreme weather events happening in Indramayu is important since EWEs there affect national agricultural and fisheries activities. During a recent EWE more than a thousand houses in Indramayu suffered from serious flooding with each home more than one meter underwater. The flood also destroyed a thousand hectares of rice plantings in 5 regencies. Identifying the dates of extreme events is one of the most important steps and has to be carried out carefully. An approach has been applied to identify the

  12. Extreme value modeling for the analysis and prediction of time series of extreme tropospheric ozone levels: a case study.

    Science.gov (United States)

    Escarela, Gabriel

    2012-06-01

    The occurrence of high concentrations of tropospheric ozone is considered as one of the most important issues of air management programs. The prediction of dangerous ozone levels for the public health and the environment, along with the assessment of air quality control programs aimed at reducing their severity, is of considerable interest to the scientific community and to policy makers. The chemical mechanisms of tropospheric ozone formation are complex, and highly variable meteorological conditions contribute additionally to difficulties in accurate study and prediction of high levels of ozone. Statistical methods offer an effective approach to understand the problem and eventually improve the ability to predict maximum levels of ozone. In this paper an extreme value model is developed to study data sets that consist of periodically collected maxima of tropospheric ozone concentrations and meteorological variables. The methods are applied to daily tropospheric ozone maxima in Guadalajara City, Mexico, for the period January 1997 to December 2006. The model adjusts the daily rate of change in ozone for concurrent impacts of seasonality and present and past meteorological conditions, which include surface temperature, wind speed, wind direction, relative humidity, and ozone. The results indicate that trend, annual effects, and key meteorological variables along with some interactions explain the variation in daily ozone maxima. Prediction performance assessments yield reasonably good results.

  13. I-Love-Q to the extreme

    Science.gov (United States)

    Silva, Hector O.; Yunes, Nicolás

    2018-01-01

    Certain bulk properties of neutron stars, in particular their moment of inertia, rotational quadrupole moment and tidal Love number, when properly normalized, are related to one another in a nearly equation of state independent way. The goal of this paper is to test these relations with extreme equations of state at supranuclear densities constrained to satisfy only a handful of generic, physically sensible conditions. By requiring that the equation of state be (i) barotropic and (ii) its associated speed of sound be real, we construct a piecewise function that matches a tabulated equation of state at low densities, while matching a stiff equation of state parametrized by its sound speed in the high-density region. We show that the I-Love-Q relations hold to 1 percent with this class of equations of state, even in the extreme case where the speed of sound becomes superluminal and independently of the transition density. We also find further support for the interpretation of the I-Love-Q relations as an emergent symmetry due to the nearly constant eccentricity of isodensity contours inside the star. These results reinforce the robustness of the I-Love-Q relations against our current incomplete picture of physics at supranuclear densities, while strengthening our confidence in the applicability of these relations in neutron star astrophysics.

  14. Extreme Programming: Maestro Style

    Science.gov (United States)

    Norris, Jeffrey; Fox, Jason; Rabe, Kenneth; Shu, I-Hsiang; Powell, Mark

    2009-01-01

    "Extreme Programming: Maestro Style" is the name of a computer programming methodology that has evolved as a custom version of a methodology, called extreme programming that has been practiced in the software industry since the late 1990s. The name of this version reflects its origin in the work of the Maestro team at NASA's Jet Propulsion Laboratory that develops software for Mars exploration missions. Extreme programming is oriented toward agile development of software resting on values of simplicity, communication, testing, and aggressiveness. Extreme programming involves use of methods of rapidly building and disseminating institutional knowledge among members of a computer-programming team to give all the members a shared view that matches the view of the customers for whom the software system is to be developed. Extreme programming includes frequent planning by programmers in collaboration with customers, continually examining and rewriting code in striving for the simplest workable software designs, a system metaphor (basically, an abstraction of the system that provides easy-to-remember software-naming conventions and insight into the architecture of the system), programmers working in pairs, adherence to a set of coding standards, collaboration of customers and programmers, frequent verbal communication, frequent releases of software in small increments of development, repeated testing of the developmental software by both programmers and customers, and continuous interaction between the team and the customers. The environment in which the Maestro team works requires the team to quickly adapt to changing needs of its customers. In addition, the team cannot afford to accept unnecessary development risk. Extreme programming enables the Maestro team to remain agile and provide high-quality software and service to its customers. However, several factors in the Maestro environment have made it necessary to modify some of the conventional extreme

  15. Mandelbrot's Extremism

    NARCIS (Netherlands)

    Beirlant, J.; Schoutens, W.; Segers, J.J.J.

    2004-01-01

    In the sixties Mandelbrot already showed that extreme price swings are more likely than some of us think or incorporate in our models.A modern toolbox for analyzing such rare events can be found in the field of extreme value theory.At the core of extreme value theory lies the modelling of maxima

  16. Modification of growth conditions by mm-waves of wood-decaying mushrooms cultures

    International Nuclear Information System (INIS)

    Avagyan, I.A.

    2016-01-01

    Basidial macromycetes are not only value food, but can be used as source of such biological active compounds as the genistein, β -glucans, glioxal-oxidase et al. In this work we used different frequencies of extremely high frequency of electromagnetic irradiation (EHF EMI) with the aim of obtaining mushroom cultures with increased fermentative activity by the modulation of its growth conditions during growth on the peptone media. We investigated the influence of the non-thermal extremely high frequency electromagnetic waves in the interval of 45-53 GHz on β-glucosidase activities of two species of wood-decaying mushroom. In this study we examined the most popular edible wood-decaying mushroom Pleurotus ostreatus, which is wide-spread in the forests and commercial mushroom Lentinula edodes, under influence of such an abiotic factor as the extremely high frequency waves in the interval of 45 GHz - 53 GHz during 20 and 40 min on the 7th day of mycelial culture's growth. After the treatment of cultures we continued their growth and on the 3th day we examined the influence of these waves on fermentative activity of mycelial extracts. The some conditions of such treatment led to significant rising of β-glucosidase activities in the extracts of mycelial cultures

  17. Global characteristics of extreme winters from a multi-millennial simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, B.G. [CSIRO Marine and Atmospheric Research, PO Box 1, Aspendale (Australia)

    2011-10-15

    Output from a multi-millennial simulation with the CSIRO Mark 2 coupled global climatic model has been analysed to determine the principal characteristics of extreme winters over the globe for ''present conditions''. Thus, this study is not concerned with possible changes in winter conditions associated with anthropogenically induced climatic change. Defining an extreme winter as having a surface temperature anomaly of below -2 standard deviations (sd) revealed a general occurrence rate over the globe of between 100 and 200 over a 6,000-year period of the simulation, with somewhat higher values over northwest North America. For temperature anomalies below -3 sd the corresponding occurrence rate drops to about 10. Spatial correlation studies revealed that extreme winters over regions in Europe, North America or Asia were very limited geographically, with time series of the surface temperature anomalies for these regions having mutual correlation coefficients of about 0.2. The temporal occurrence rates of winters (summers) having sd below -3 (above +3) were very asymmetric and sporadic, suggesting that such events arise from stochastic influences. Multi-year sequences of extreme winters were comparatively rare events. Detailed analysis revealed that the temporal and spatial evolution of the monthly surface temperature anomalies associated with an individual extreme winter were well replicated in the simulation, as were daily time series of such anomalies. Apart from an influence of the North Atlantic Oscillation on extreme winters in Europe, other prominent climatic oscillations were very poorly correlated with such winters. Rather modest winter temperature anomalies were found in the southern hemisphere. (orig.)

  18. Hydrological impacts of precipitation extremes in the Huaihe River Basin, China.

    Science.gov (United States)

    Yang, Mangen; Chen, Xing; Cheng, Chad Shouquan

    2016-01-01

    Precipitation extremes play a key role in flooding risks over the Huaihe River Basin, which is important to understand their hydrological impacts. Based on observed daily precipitation and streamflow data from 1958 to 2009, eight precipitation indices and three streamflow indices were calculated for the study of hydrological impacts of precipitation extremes. The results indicate that the wet condition intensified in the summer wet season and the drought condition was getting worse in the autumn dry season in the later years of the past 50 years. The river basin had experienced higher heavy rainfall-related flooding risks in summer and more severe drought in autumn in the later of the period. The extreme precipitation events or consecutive heavy rain day events led to the substantial increases in streamflow extremes, which are the main causes of frequent floods in the Huaihe River Basin. The large inter-annual variation of precipitation anomalies in the upper and central Huaihe River Basin are the major contributor for the regional frequent floods and droughts.

  19. Coordinated Hard Sphere Mixture (CHaSM): A fast approximate model for oxide and silicate melts at extreme conditions

    Science.gov (United States)

    Wolf, A. S.; Asimow, P. D.; Stevenson, D. J.

    2015-12-01

    Recent first-principles calculations (e.g. Stixrude, 2009; de Koker, 2013), shock-wave experiments (Mosenfelder, 2009), and diamond-anvil cell investigations (Sanloup, 2013) indicate that silicate melts undergo complex structural evolution at high pressure. The observed increase in cation-coordination (e.g. Karki, 2006; 2007) induces higher compressibilities and lower adiabatic thermal gradients in melts as compared with their solid counterparts. These properties are crucial for understanding the evolution of impact-generated magma oceans, which are dominated by the poorly understood behavior of silicates at mantle pressures and temperatures (e.g. Stixrude et al. 2009). Probing these conditions is difficult for both theory and experiment, especially given the large compositional space (MgO-SiO2-FeO-Al2O3-etc). We develop a new model to understand and predict the behavior of oxide and silicate melts at extreme P-T conditions (Wolf et al., 2015). The Coordinated Hard Sphere Mixture (CHaSM) extends the Hard Sphere mixture model, accounting for the range of coordination states for each cation in the liquid. Using approximate analytic expressions for the hard sphere model, this fast statistical method compliments classical and first-principles methods, providing accurate thermodynamic and structural property predictions for melts. This framework is applied to the MgO system, where model parameters are trained on a collection of crystal polymorphs, producing realistic predictions of coordination evolution and the equation of state of MgO melt over a wide P-T range. Typical Mg-coordination numbers are predicted to evolve continuously from 5.25 (0 GPa) to 8.5 (250 GPa), comparing favorably with first-principles Molecular Dynamics (MD) simulations. We begin extending the model to a simplified mantle chemistry using empirical potentials (generally accurate over moderate pressure ranges, consuming classical MD calculations. This approach also sheds light on the universality

  20. Imaging of upper extremity stress fractures in the athlete.

    Science.gov (United States)

    Anderson, Mark W

    2006-07-01

    Although it is much less common than injuries in the lower extremities, an upper extremity stress injury can have a significant impact on an athlete. If an accurate and timely diagnosis is to be made, the clinician must have a high index of suspicion of a stress fracture in any athlete who is involved in a throwing, weightlifting, or upper extremity weight-bearing sport and presents with chronic pain in the upper extremity. Imaging should play an integral role in the work-up of these patients; if initial radiographs are unrevealing, further cross-sectional imaging should be strongly considered. Although a three-phase bone scan is highly sensitive in this regard, MRI has become the study of choice at most centers.

  1. Extreme Hurricane-Generated Waves in Gulf of Mexico

    National Research Council Canada - National Science Library

    Alberto, Carlos; Fernandes, Santos

    2005-01-01

    .... Although WaveWatchIII (WW3) is used by many operational forecasting centers around the world, there is a lack of field studies to evaluate its accuracy in regional applications and under extreme conditions, such as Hurricanes...

  2. A low cost, high precision extreme/harsh cold environment, autonomous sensor data gathering and transmission platform.

    Science.gov (United States)

    Chetty, S.; Field, L. A.

    2014-12-01

    SWIMS III, is a low cost, autonomous sensor data gathering platform developed specifically for extreme/harsh cold environments. Arctic ocean's continuing decrease of summer-time ice is related to rapidly diminishing multi-year ice due to the effects of climate change. Ice911 Research aims to develop environmentally inert materials that when deployed will increase the albedo, enabling the formation and/preservation of multi-year ice. SWIMS III's sophisticated autonomous sensors are designed to measure the albedo, weather, water temperature and other environmental parameters. This platform uses low cost, high accuracy/precision sensors, extreme environment command and data handling computer system using satellite and terrestrial wireless solution. The system also incorporates tilt sensors and sonar based ice thickness sensors. The system is light weight and can be deployed by hand by a single person. This presentation covers the technical, and design challenges in developing and deploying these platforms.

  3. High intensity vacuum ultraviolet and extreme ultraviolet production by noncollinear mixing in laser vaporized media

    Energy Technology Data Exchange (ETDEWEB)

    Todt, Michael A.; Albert, Daniel R.; Davis, H. Floyd, E-mail: hfd1@cornell.edu [Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301 (United States)

    2016-06-15

    A method is described for generating intense pulsed vacuum ultraviolet (VUV) and extreme ultraviolet (XUV) laser radiation by resonance enhanced four-wave mixing of commercial pulsed nanosecond lasers in laser vaporized mercury under windowless conditions. By employing noncollinear mixing of the input beams, the need of dispersive elements such as gratings for separating the VUV/XUV from the residual UV and visible beams is eliminated. A number of schemes are described, facilitating access to the 9.9–14.6 eV range. A simple and convenient scheme for generating wavelengths of 125 nm, 112 nm, and 104 nm (10 eV, 11 eV, and 12 eV) using two dye lasers without the need for dye changes is described.

  4. The family as a determinant of stunting in children living in conditions of extreme poverty: a case-control study

    Directory of Open Access Journals (Sweden)

    Doubova Svetlana V

    2004-11-01

    Full Text Available Abstract Background Malnutrition in children can be a consequence of unfavourable socioeconomic conditions. However, some families maintain adequate nutritional status in their children despite living in poverty. The aim of this study was to ascertain whether family-related factors are determinants of stunting in young Mexican children living in extreme poverty, and whether these factors differ between rural or urban contexts. Methods A case-control study was conducted in one rural and one urban extreme poverty level areas in Mexico. Cases comprised stunted children aged between 6 and 23 months. Controls were well-nourished children. Independent variables were defined in five dimensions: family characteristics; family income; household allocation of resources and family organisation; social networks; and child health care. Information was collected from 108 cases and 139 controls in the rural area and from 198 cases and 211 controls in the urban area. Statistical analysis was carried out separately for each area; unconditional multiple logistic regression analyses were performed to obtain the best explanatory model for stunting. Results In the rural area, a greater risk of stunting was associated with father's occupation as farmer and the presence of family networks for child care. The greatest protective effect was found in children cared for exclusively by their mothers. In the urban area, risk factors for stunting were father with unstable job, presence of small social networks, low rate of attendance to the Well Child Program activities, breast-feeding longer than six months, and two variables within the family characteristics dimension (longer duration of parents' union and migration from rural to urban area. Conclusions This study suggests the influence of the family on the nutritional status of children under two years of age living in extreme poverty areas. Factors associated with stunting were different in rural and urban communities

  5. Extreme value analysis of meterological parameters observed at Narora during the period 1989-2001

    International Nuclear Information System (INIS)

    Varakhedkar, V.K.; Dube, B.; Gurg, R.P.

    2002-08-01

    The design of engineering structures requires an understanding of extreme weather conditions that may occur at the site of interest, which is very essential, so that the structures can be designed to withstand weather stresses. In this report an analysis of extreme values of meteorological parameters observed at Narora for the period 1989- 2001 is described. The parameters considered are maximum and minimum air temperature, minimum relative humidity, maximum wind speed, maximum rainfall in a day and month, and annual rainfall. The extreme value analysis reveals that the variables such as annual maximum air temperature, minimum relative humidity and monthly maximum rainfall obey Fisher -Tippet Type -I extreme value distribution where as annual minimum air temperature, maximum hourly wind speed, daily maximum rainfall and maximum and minimum annual rainfall, obey Fisher -Tippet Type -2 extreme value distribution function. Various distribution function parameters for each variable are determined. Extreme values corresponding to return periods of 50 years and 100 years are worked out. These derived extreme values are particularly useful for arriving at suitable design values to ensure the safety of any civil structure in Narora area with respect to stresses due to weather conditions. (author)

  6. Surface (glyco-)proteins: primary structure and crystallization under microgravity conditions

    Science.gov (United States)

    Claus, H.; Akca, E.; Schultz, N.; Karbach, G.; Schlott, B.; Debaerdemaeker, T.; De Clercq, J.-P.; König, H.

    2001-08-01

    The Archaea comprise microorganisms that live under environmental extremes, like high temperature, low pH value or high salt concentration. Their cells are often covered by a single layer of (glyco)protein subunits (S-layer) in hexagonal arrangement. In order to get further hints about the molecular mechanisms of protein stabilization we compared the primary and secondary structures of archaeal S-layer (glyco)proteins. We found an increase of charged amino acids in the S-layer proteins of the extreme thermophilic species compared to their mesophilic counterparts. Our data and those of other authors suggest that ionic interactions, e.g., salt bridges seem to be played a major role in protein stabilization at high temperatures. Despite the differences in the growth optima and the predominance of some amino acids the primary structures of S-layers revealed also a significant degree of identity between phylogenetically related archaea. These obervations indicate that protein sequences of S-layers have been conserved during the evolution from extremely thermophilic to mesophilic life. To support these findings the three-dimensional structure of the S-layer proteins has to be elucidated. Recently, we described the first successful crystallization of an extreme thermophilic surface(glyco)protein under microgravity conditions.

  7. Minute synthesis of extremely stable gold nanoparticles.

    Science.gov (United States)

    Zhou, Min; Wang, Baoxiang; Rozynek, Zbigniew; Xie, Zhaohui; Fossum, Jon Otto; Yu, Xiaofeng; Raaen, Steinar

    2009-12-16

    We describe a rapid environmentally friendly wet-chemical approach to synthesize extremely stable non-toxic, biocompatible, water-soluble monodispersed gold nanoparticles (AuNPs) in one step at room temperature. The particles have been successfully achieved in just a few minutes by merely adding sodium hydroxide (NaOH) acting as an initiator for the reduction of HAuCl(4) in aqueous solution in the presence of polyvinylpyrrolidone (PVP) without the use of any reducing agent. It is also proved to be highly efficient for the preparation of AuNPs with controllable sizes. The AuNPs show remarkable stability in water media with high concentrations of salt, various buffer solutions and physiological conditions in biotechnology and biomedicine. Moreover, the AuNPs are also non-toxic at high concentration (100 microM). Therefore, it provides great opportunities to use these AuNPs for biotechnology and biomedicine. This new approach also involved several green chemistry concepts, such as the selection of environmentally benign reagents and solvents, without energy consumption, and less reaction time.

  8. Minute synthesis of extremely stable gold nanoparticles

    International Nuclear Information System (INIS)

    Zhou Min; Wang Baoxiang; Rozynek, Zbigniew; Xie Zhaohui; Fossum, Jon Otto; Yu Xiaofeng; Raaen, Steinar

    2009-01-01

    We describe a rapid environmentally friendly wet-chemical approach to synthesize extremely stable non-toxic, biocompatible, water-soluble monodispersed gold nanoparticles (AuNPs) in one step at room temperature. The particles have been successfully achieved in just a few minutes by merely adding sodium hydroxide (NaOH) acting as an initiator for the reduction of HAuCl 4 in aqueous solution in the presence of polyvinylpyrrolidone (PVP) without the use of any reducing agent. It is also proved to be highly efficient for the preparation of AuNPs with controllable sizes. The AuNPs show remarkable stability in water media with high concentrations of salt, various buffer solutions and physiological conditions in biotechnology and biomedicine. Moreover, the AuNPs are also non-toxic at high concentration (100 μM). Therefore, it provides great opportunities to use these AuNPs for biotechnology and biomedicine. This new approach also involved several green chemistry concepts, such as the selection of environmentally benign reagents and solvents, without energy consumption, and less reaction time.

  9. High gain requirements and high field Tokamak experiments

    International Nuclear Information System (INIS)

    Cohn, D.R.

    1994-01-01

    Operation at sufficiently high gain (ratio of fusion power to external heating power) is a fundamental requirement for tokamak power reactors. For typical reactor concepts, the gain is greater than 25. Self-heating from alpha particles in deuterium-tritium plasmas can greatly reduce ητ/temperature requirements for high gain. A range of high gain operating conditions is possible with different values of alpha-particle efficiency (fraction of alpha-particle power that actually heats the plasma) and with different ratios of self heating to external heating. At one extreme, there is ignited operation, where all of the required plasma heating is provided by alpha particles and the alpha-particle efficiency is 100%. At the other extreme, there is the case of no heating contribution from alpha particles. ητ/temperature requirements for high gain are determined as a function of alpha-particle heating efficiency. Possibilities for high gain experiments in deuterium-tritium, deuterium, and hydrogen plasmas are discussed

  10. Distributing urban resilience to extreme precipitation events with green infrastructure

    Science.gov (United States)

    Montalto, F. A.; Catalano De Sousa, M.; Yu, Z.

    2013-12-01

    New urban green spaces are being designed to manage stormwater, but their performance in a changing climate is untested. Key questions pertain to the ability of these systems to mitigate flood and sewer overflow concerns during impact of extreme events on, and to withstand (biologically and physically) increased frequency and intensity of drought and flood conditions. In this presentation, we present field data characterizing performance of a bioretention area, a stormwater treatment wetland, and a green roof under Hurricane Irene (2011), Superstorm Sandy (2012), and a variety of extreme precipitation events during the summer of 2013. Specifically, we characterize the fate and volume of incident runon and/or precipitation to the facilities during these extreme events, and compare them to long term monitored performance metrics. We also present laboratory test results documenting how vegetation in these facilities stands up to simulated flood and drought conditions. The results are discussed in the context of predicted climate change, specifically associated with the amount and timing of precipitation.

  11. Statistical Model of Extreme Shear

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose; Larsen, Gunner Chr.

    2005-01-01

    In order to continue cost-optimisation of modern large wind turbines, it is important to continuously increase the knowledge of wind field parameters relevant to design loads. This paper presents a general statistical model that offers site-specific prediction of the probability density function...... by a model that, on a statistically consistent basis, describes the most likely spatial shape of an extreme wind shear event. Predictions from the model have been compared with results from an extreme value data analysis, based on a large number of full-scale measurements recorded with a high sampling rate...

  12. Improving simulated long-term responses of vegetation to temperature and precipitation extremes using the ACME land model

    Science.gov (United States)

    Ricciuto, D. M.; Warren, J.; Guha, A.

    2017-12-01

    While carbon and energy fluxes in current Earth system models generally have reasonable instantaneous responses to extreme temperature and precipitation events, they often do not adequately represent the long-term impacts of these events. For example, simulated net primary productivity (NPP) may decrease during an extreme heat wave or drought, but may recover rapidly to pre-event levels following the conclusion of the extreme event. However, field measurements indicate that long-lasting damage to leaves and other plant components often occur, potentially affecting the carbon and energy balance for months after the extreme event. The duration and frequency of such extreme conditions is likely to shift in the future, and therefore it is critical for Earth system models to better represent these processes for more accurate predictions of future vegetation productivity and land-atmosphere feedbacks. Here we modify the structure of the Accelerated Climate Model for Energy (ACME) land surface model to represent long-term impacts and test the improved model against observations from experiments that applied extreme conditions in growth chambers. Additionally, we test the model against eddy covariance measurements that followed extreme conditions at selected locations in North America, and against satellite-measured vegetation indices following regional extreme events.

  13. High-definition infrared thermography of ice nucleation and propagation in wheat under natural frost conditions and controlled freezing.

    Science.gov (United States)

    Livingston, David P; Tuong, Tan D; Murphy, J Paul; Gusta, Lawrence V; Willick, Ian; Wisniewski, Micheal E

    2018-04-01

    An extremely high resolution infrared camera demonstrated various freezing events in wheat under natural conditions. Many of those events shed light on years of misunderstanding regarding freezing in small grains. Infrared thermography has enhanced our knowledge of ice nucleation and propagation in plants through visualization of the freezing process. The majority of infrared analyses have been conducted under controlled conditions and often on individual organs instead of whole plants. In the present study, high-definition (1280 × 720 pixel resolution) infrared thermography was used under natural conditions to visualize the freezing process of wheat plants during freezing events in 2016 and 2017. Plants within plots were found to freeze one at a time throughout the night and in an apparently random manner. Leaves on each plant also froze one at a time in an age-dependent pattern with oldest leaves freezing first. Contrary to a common assumption that freezing begins in the upper parts of leaves; freezing began at the base of the plant and spread upwards. The high resolution camera used was able to verify that a two stage sequence of freezing began within vascular bundles. Neither of the two stages was lethal to leaves, but a third stage was demonstrated at colder temperatures that was lethal and was likely a result of dehydration stress; this stage of freezing was not detectable by infrared. These results underscore the complexity of the freezing process in small grains and indicate that comprehensive observational studies are essential to identifying and selecting freezing tolerance traits in grain crops.

  14. How extreme is extreme hourly precipitation?

    Science.gov (United States)

    Papalexiou, Simon Michael; Dialynas, Yannis G.; Pappas, Christoforos

    2016-04-01

    The importance of accurate representation of precipitation at fine time scales (e.g., hourly), directly associated with flash flood events, is crucial in hydrological design and prediction. The upper part of a probability distribution, known as the distribution tail, determines the behavior of extreme events. In general, and loosely speaking, tails can be categorized in two families: the subexponential and the hyperexponential family, with the first generating more intense and more frequent extremes compared to the latter. In past studies, the focus has been mainly on daily precipitation, with the Gamma distribution being the most popular model. Here, we investigate the behaviour of tails of hourly precipitation by comparing the upper part of empirical distributions of thousands of records with three general types of tails corresponding to the Pareto, Lognormal, and Weibull distributions. Specifically, we use thousands of hourly rainfall records from all over the USA. The analysis indicates that heavier-tailed distributions describe better the observed hourly rainfall extremes in comparison to lighter tails. Traditional representations of the marginal distribution of hourly rainfall may significantly deviate from observed behaviours of extremes, with direct implications on hydroclimatic variables modelling and engineering design.

  15. Sensitivity of European wheat to extreme weather

    DEFF Research Database (Denmark)

    Mäkinen, H; Kaseva, J; Trnka, M

    2018-01-01

    The frequency and intensity of extreme weather is increasing concomitant with changes in the global climate change. Although wheat is the most important food crop in Europe, there is currently no comprehensive empirical information available regarding the sensitivity of European wheat to extreme...... weather. In this study, we assessed the sensitivity of European wheat yields to extreme weather related to phenology (sowing, heading) in cultivar trials across Europe (latitudes 37.21° to 61.34° and longitudes −6.02° to 26.24°) during the period 1991–2014. All the observed agro-climatic extremes (≥31 °C...... wheat cultivars that responded positively (+10%) to drought after sowing, or frost during winter (−15 °C and −20 °C). Positive responses to extremes were often shown by cultivars associated with specific regions, such as good performance under high temperatures by southern-origin cultivars. Consequently...

  16. Microbial survival of space vacuum and extreme ultraviolet irradiation: strain isolation and analysis during a rocket flight.

    Science.gov (United States)

    Saffary, Roya; Nandakumar, Renu; Spencer, Dennis; Robb, Frank T; Davila, Joseph M; Swartz, Marvin; Ofman, Leon; Thomas, Roger J; DiRuggiero, Jocelyne

    2002-09-24

    We have recovered new isolates from hot springs, in Yellowstone National Park and the Kamchatka Peninsula, after gamma-irradiation and exposure to high vacuum (10(-6) Pa) of the water and sediment samples. The resistance to desiccation and ionizing radiation of one of the isolates, Bacillus sp. strain PS3D, was compared to that of the mesophilic bacterium, Deinococcus radiodurans, a species well known for its extraordinary resistance to desiccation and high doses of ionizing radiation. Survival of these two microorganisms was determined in real and simulated space conditions, including exposure to extreme UV radiation (10-100 nm) during a rocket flight. We found that up to 15 days of desiccation alone had little effect on the viability of either bacterium. In contrast, exposure to space vacuum ( approximately 10(-6) Pa) decreased cell survival by two and four orders of magnitude for Bacillus sp. strain PS3D and D. radiodurans, respectively. Simultaneous exposure to space vacuum and extreme UV radiation further decreased the survival of both organisms, compared to unirradiated controls. This is the first report on the isolated effect of extreme UV at 30 nm on cell survival. Extreme UV can only be transmitted through high vacuum, therefore its penetration into the cells may only be superficial, suggesting that in contrast to near UV, membrane proteins rather than DNA were damaged by the radiation.

  17. Relationships between High Impact Tropical Rainfall Events and Environmental Conditions

    Science.gov (United States)

    Painter, C.; Varble, A.; Zipser, E. J.

    2017-12-01

    While rainfall increases as moisture and vertical motion increase, relationships between regional environmental conditions and rainfall event characteristics remain more uncertain. Of particular importance are long duration, heavy rain rate, and significant accumulation events that contribute sizable fractions of overall precipitation over short time periods. This study seeks to establish relationships between observed rainfall event properties and environmental conditions. Event duration, rain rate, and rainfall accumulation are derived using the Tropical Rainfall Measuring Mission (TRMM) 3B42 3-hourly, 0.25° resolution rainfall retrieval from 2002-2013 between 10°N and 10°S. Events are accumulated into 2.5° grid boxes and matched to monthly mean total column water vapor (TCWV) and 500-hPa vertical motion (omega) in each 2.5° grid box, retrieved from ERA-interim reanalysis. Only months with greater than 3 mm/day rainfall are included to ensure sufficient sampling. 90th and 99th percentile oceanic events last more than 20% longer and have rain rates more than 20% lower than those over land for a given TCWV-omega condition. Event duration and accumulation are more sensitive to omega than TCWV over oceans, but more sensitive to TCWV than omega over land, suggesting system size, propagation speed, and/or forcing mechanism differences for land and ocean regions. Sensitivities of duration, rain rate, and accumulation to TCWV and omega increase with increasing event extremity. For 3B42 and ERA-Interim relationships, the 90th percentile oceanic event accumulation increases by 0.93 mm for every 1 Pa/min change in rising motion, but this increases to 3.7 mm for every 1 Pa/min for the 99th percentile. Over land, the 90th percentile event accumulation increases by 0.55 mm for every 1 mm increase in TCWV, whereas the 99th percentile increases by 0.90 mm for every 1 mm increase in TCWV. These changes in event accumulation are highly correlated with changes in event

  18. Numerical modeling of materials under extreme conditions

    CERN Document Server

    Brown, Eric

    2014-01-01

    The book presents twelve state of the art contributions in the field of numerical modeling of materials subjected to large strain, high strain rates, large pressure and high stress triaxialities, organized into two sections. The first part is focused on high strain rate-high pressures such as those occurring in impact dynamics and shock compression related phenomena, dealing with material response identification, advanced modeling incorporating microstructure and damage, stress waves propagation in solids and structures response under impact. The latter part is focused on large strain-low strain rates applications such as those occurring in technological material processing, dealing with microstructure and texture evolution, material response at elevated temperatures, structural behavior under large strain and multi axial state of stress.

  19. Identification of Climate Change with Generalized Extreme Value (GEV) Distribution Approach

    International Nuclear Information System (INIS)

    Rahayu, Anita

    2013-01-01

    Some events are difficult to avoid and gives considerable influence to humans and the environment is extreme weather and climate change. Many of the problems that require knowledge about the behavior of extreme values and one of the methods used are the Extreme Value Theory (EVT). EVT used to draw up reliable systems in a variety of conditions, so as to minimize the risk of a major disaster. There are two methods for identifying extreme value, Block Maxima with Generalized Extreme Value (GEV) distribution approach and Peaks over Threshold (POT) with Generalized Pareto Distribution (GPD) approach. This research in Indramayu with January 1961-December 2003 period, the method used is Block Maxima with GEV distribution approach. The result showed that there is no climate change in Indramayu with January 1961-December 2003 period.

  20. The problem of defining contemporary right-wing extremism in political theory

    Directory of Open Access Journals (Sweden)

    Đorić Marija

    2016-01-01

    Full Text Available The subject matter of research in this paper is theoretical controversy related to the definition of right-wing extremism. Given the fact that extremism is a variable, amorphous and insufficiently researched phenomenon, largely conditioned by time, space, political and cultural differences, there is a great confusion in the field of political science when defining right-wing extremism. The problem of researching right-wing extremism is additionally complicated by various terms that are being used in the contemporary literature as its synonyms, such as right-wing radicalism, neo-Fascism, ultra-radicalism, etc. In order to provide the most valid theoretical determination of right-wing extremism, the author provides a detailed analysis of all the components constituting this phenomenon and examines their causality. In the political praxis, the term extremism is extensively abused, which additionally complicates its determination. Videlicet, politicians often use term 'extremist' in order to discredit their political opponents. While during the French revolution aristocracy saw the bourgeoisie as extremists, the members of the working class later stated that the bourgeoisie were extremists. The problem lies in the fact that, in politics, extremists are not only the ones who use violence as modus operandi; indeed, it is also used by political opponents who do not belong to the extreme political option. Another aggravating factor in defining right-wing extremism is that many administrative and academic definitions do not make a clear distinction between extremism and related phenomena, such as terrorism, radicalism and populism. Extremism is most often equaled with terrorism, which gives rise to another problem in defining this phenomenon. The relation between extremism and terrorism is the relation of general and specific. Namely, every act of terrorism is concurrently considered to be an act of extremism, but not vice versa, given the fact that