WorldWideScience

Sample records for high average age

  1. High average power supercontinuum sources

    Indian Academy of Sciences (India)

    J C Travers

    2010-11-01

    The physical mechanisms and basic experimental techniques for the creation of high average spectral power supercontinuum sources is briefly reviewed. We focus on the use of high-power ytterbium-doped fibre lasers as pump sources, and the use of highly nonlinear photonic crystal fibres as the nonlinear medium. The most common experimental arrangements are described, including both continuous wave fibre laser systems with over 100 W pump power, and picosecond mode-locked, master oscillator power fibre amplifier systems, with over 10 kW peak pump power. These systems can produce broadband supercontinua with over 50 and 1 mW/nm average spectral power, respectively. Techniques for numerical modelling of the supercontinuum sources are presented and used to illustrate some supercontinuum dynamics. Some recent experimental results are presented.

  2. High-Average Power Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, David H.; /SLAC; Power, John G.; /Argonne

    2012-09-05

    There has been significant progress in the development of high-power facilities in recent years yet major challenges remain. The task of WG4 was to identify which facilities were capable of addressing the outstanding R&D issues presently preventing high-power operation. To this end, information from each of the facilities represented at the workshop was tabulated and the results are presented herein. A brief description of the major challenges is given, but the detailed elaboration can be found in the other three working group summaries.

  3. High Average Power Yb:YAG Laser

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, L E; Beach, R J; Payne, S A

    2001-05-23

    We are working on a composite thin-disk laser design that can be scaled as a source of high brightness laser power for tactical engagement and other high average power applications. The key component is a diffusion-bonded composite comprising a thin gain-medium and thicker cladding that is strikingly robust and resolves prior difficulties with high average power pumping/cooling and the rejection of amplified spontaneous emission (ASE). In contrast to high power rods or slabs, the one-dimensional nature of the cooling geometry and the edge-pump geometry scale gracefully to very high average power. The crucial design ideas have been verified experimentally. Progress this last year included: extraction with high beam quality using a telescopic resonator, a heterogeneous thin film coating prescription that meets the unusual requirements demanded by this laser architecture, thermal management with our first generation cooler. Progress was also made in design of a second-generation laser.

  4. High Average Power Optical FEL Amplifiers

    CERN Document Server

    Ben-Zvi, I; Litvinenko, V

    2005-01-01

    Historically, the first demonstration of the FEL was in an amplifier configuration at Stanford University. There were other notable instances of amplifying a seed laser, such as the LLNL amplifier and the BNL ATF High-Gain Harmonic Generation FEL. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance a 100 kW average power FEL. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting energy recovery linacs combine well with the high-gain FEL amplifier to produce unprecedented average power FELs with some advantages. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Li...

  5. High average-power induction linacs

    Energy Technology Data Exchange (ETDEWEB)

    Prono, D.S.; Barrett, D.; Bowles, E.; Caporaso, G.J.; Chen, Yu-Jiuan; Clark, J.C.; Coffield, F.; Newton, M.A.; Nexsen, W.; Ravenscroft, D.

    1989-03-15

    Induction linear accelerators (LIAs) are inherently capable of accelerating several thousand amperes of /approximately/ 50-ns duration pulses to > 100 MeV. In this paper we report progress and status in the areas of duty factor and stray power management. These technologies are vital if LIAs are to attain high average power operation. 13 figs.

  6. Materials for high average power lasers

    Energy Technology Data Exchange (ETDEWEB)

    Marion, J.E.; Pertica, A.J.

    1989-01-01

    Unique materials properties requirements for solid state high average power (HAP) lasers dictate a materials development research program. A review of the desirable laser, optical and thermo-mechanical properties for HAP lasers precedes an assessment of the development status for crystalline and glass hosts optimized for HAP lasers. 24 refs., 7 figs., 1 tab.

  7. A database of age-appropriate average MRI templates.

    Science.gov (United States)

    Richards, John E; Sanchez, Carmen; Phillips-Meek, Michelle; Xie, Wanze

    2016-01-01

    This article summarizes a life-span neurodevelopmental MRI database. The study of neurostructural development or neurofunctional development has been hampered by the lack of age-appropriate MRI reference volumes. This causes misspecification of segmented data, irregular registrations, and the absence of appropriate stereotaxic volumes. We have created the "Neurodevelopmental MRI Database" that provides age-specific reference data from 2 weeks through 89 years of age. The data are presented in fine-grained ages (e.g., 3 months intervals through 1 year; 6 months intervals through 19.5 years; 5 year intervals from 20 through 89 years). The base component of the database at each age is an age-specific average MRI template. The average MRI templates are accompanied by segmented partial volume estimates for segmenting priors, and a common stereotaxic atlas for infant, pediatric, and adult participants. The database is available online (http://jerlab.psych.sc.edu/NeurodevelopmentalMRIDatabase/).

  8. MACHINE PROTECTION FOR HIGH AVERAGE CURRENT LINACS

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Kevin; Allison, Trent; Evans, Richard; Coleman, James; Grippo, Albert

    2003-05-01

    A fully integrated Machine Protection System (MPS) is critical to efficient commissioning and safe operation of all high current accelerators. The Jefferson Lab FEL [1,2] has multiple electron beam paths and many different types of diagnostic insertion devices. The MPS [3] needs to monitor both the status of these devices and the magnet settings which define the beam path. The matrix of these devices and beam paths are programmed into gate arrays, the output of the matrix is an allowable maximum average power limit. This power limit is enforced by the drive laser for the photocathode gun. The Beam Loss Monitors (BLMs), RF status, and laser safety system status are also inputs to the control matrix. There are 8 Machine Modes (electron path) and 8 Beam Modes (average power limits) that define the safe operating limits for the FEL. Combinations outside of this matrix are unsafe and the beam is inhibited. The power limits range from no beam to 2 megawatts of electron beam power.

  9. Time averaging, ageing and delay analysis of financial time series

    Science.gov (United States)

    Cherstvy, Andrey G.; Vinod, Deepak; Aghion, Erez; Chechkin, Aleksei V.; Metzler, Ralf

    2017-06-01

    We introduce three strategies for the analysis of financial time series based on time averaged observables. These comprise the time averaged mean squared displacement (MSD) as well as the ageing and delay time methods for varying fractions of the financial time series. We explore these concepts via statistical analysis of historic time series for several Dow Jones Industrial indices for the period from the 1960s to 2015. Remarkably, we discover a simple universal law for the delay time averaged MSD. The observed features of the financial time series dynamics agree well with our analytical results for the time averaged measurables for geometric Brownian motion, underlying the famed Black-Scholes-Merton model. The concepts we promote here are shown to be useful for financial data analysis and enable one to unveil new universal features of stock market dynamics.

  10. Industrial Applications of High Average Power FELS

    CERN Document Server

    Shinn, Michelle D

    2005-01-01

    The use of lasers for material processing continues to expand, and the annual sales of such lasers exceeds $1 B (US). Large scale (many m2) processing of materials require the economical production of laser powers of the tens of kilowatts, and therefore are not yet commercial processes, although they have been demonstrated. The development of FELs based on superconducting RF (SRF) linac technology provides a scaleable path to laser outputs above 50 kW in the IR, rendering these applications economically viable, since the cost/photon drops as the output power increases. This approach also enables high average power ~ 1 kW output in the UV spectrum. Such FELs will provide quasi-cw (PRFs in the tens of MHz), of ultrafast (pulsewidth ~ 1 ps) output with very high beam quality. This talk will provide an overview of applications tests by our facility's users such as pulsed laser deposition, laser ablation, and laser surface modification, as well as present plans that will be tested with our upgraded FELs. These upg...

  11. Age-specific average head template for typically developing 6-month-old infants.

    Directory of Open Access Journals (Sweden)

    Lisa F Akiyama

    Full Text Available Due to the rapid anatomical changes that occur within the brain structure in early human development and the significant differences between infant brains and the widely used standard adult templates, it becomes increasingly important to utilize appropriate age- and population-specific average templates when analyzing infant neuroimaging data. In this study we created a new and highly detailed age-specific unbiased average head template in a standard MNI152-like infant coordinate system for healthy, typically developing 6-month-old infants by performing linear normalization, diffeomorphic normalization and iterative averaging processing on 60 subjects' structural images. The resulting age-specific average templates in a standard MNI152-like infant coordinate system demonstrate sharper anatomical detail and clarity compared to existing infant average templates and successfully retains the average head size of the 6-month-old infant. An example usage of the average infant templates transforms magnetoencephalography (MEG estimated activity locations from MEG's subject-specific head coordinate space to the standard MNI152-like infant coordinate space. We also created a new atlas that reflects the true 6-month-old infant brain anatomy. Average templates and atlas are publicly available on our website (http://ilabs.washington.edu/6-m-templates-atlas.

  12. High Brightness, High Average Current Injector Development at Cornell

    CERN Document Server

    Sinclair, C K

    2005-01-01

    Cornell University is constructing a 100 mA average current, high brightness electron injector for a planned Energy Recovery Linac (ERL) hard X-ray synchrotron radiation source. This injector will employ a very high voltage DC gun with a negative electron affinity photoemission cathode. Relatively long duration electron pulses from the photocathode will be drift bunched, and accelerated to 5-15 MeV with five two-cell, 1300 MHz superconducting cavities. The total beam power will be limited to 575 kW by the DC and RF power sources. A genetic algorithm based computational optimization of this injector has resulted in simulated rms normalized emittances of 0.1 mm-mrad at 80 pC/bunch, and 0.7 mm-mrad at 1 nC/bunch. The many technical issues and their design solutions will be discussed. Construction of the gun and the SRF cavities is well underway. The schedule for completion, and the planned measurements, will be presented.

  13. High Average Current Electron Guns for High-Power FELs

    Science.gov (United States)

    2009-12-09

    FELs 10 Appendix B: Thermionic Injectors 11 Appendix C: Grid Fields and Bunch Emittance 13 Appendix D: PARMELA Simulation of an IOT Gun 16...Inductive Output Tube ( IOT ) amplifiers [32-34] and can generate average currents of ~1 A, peak currents of ~ 5-10 A, cathode-anode voltages of ~ 35...of grid wires, centered at z = zG and x = ±a, ±3a, ±5a, ..., is given by <D(JC,Z) = - X n = ±l.±3. Fa(x,z) Gn(x,z) ( C3 ) where *0 = (1 / 2

  14. Estimation of differences and ratios of average age at first occurrence

    NARCIS (Netherlands)

    Boshuizen, H.C.; Greenland, S.

    1996-01-01

    Average age at first occurrence of a disease is easier to interpret than the incidence rate, which can be difficult to interpret for a common disease. Basic methods for estimating univariate differences and ratios for average age at first occurrence are outlined and illustrated with a real-life exam

  15. High-average-power diode-pumped Yb: YAG lasers

    Energy Technology Data Exchange (ETDEWEB)

    Avizonis, P V; Beach, R; Bibeau, C M; Emanuel, M A; Harris, D G; Honea, E C; Monroe, R S; Payne, S A; Skidmore, J A; Sutton, S B

    1999-10-01

    A scaleable diode end-pumping technology for high-average-power slab and rod lasers has been under development for the past several years at Lawrence Livermore National Laboratory (LLNL). This technology has particular application to high average power Yb:YAG lasers that utilize a rod configured gain element. Previously, this rod configured approach has achieved average output powers in a single 5 cm long by 2 mm diameter Yb:YAG rod of 430 W cw and 280 W q-switched. High beam quality (M{sup 2} = 2.4) q-switched operation has also been demonstrated at over 180 W of average output power. More recently, using a dual rod configuration consisting of two, 5 cm long by 2 mm diameter laser rods with birefringence compensation, we have achieved 1080 W of cw output with an M{sup 2} value of 13.5 at an optical-to-optical conversion efficiency of 27.5%. With the same dual rod laser operated in a q-switched mode, we have also demonstrated 532 W of average power with an M{sup 2} < 2.5 at 17% optical-to-optical conversion efficiency. These q-switched results were obtained at a 10 kHz repetition rate and resulted in 77 nsec pulse durations. These improved levels of operational performance have been achieved as a result of technology advancements made in several areas that will be covered in this manuscript. These enhancements to our architecture include: (1) Hollow lens ducts that enable the use of advanced cavity architectures permitting birefringence compensation and the ability to run in large aperture-filling near-diffraction-limited modes. (2) Compound laser rods with flanged-nonabsorbing-endcaps fabricated by diffusion bonding. (3) Techniques for suppressing amplified spontaneous emission (ASE) and parasitics in the polished barrel rods.

  16. Thermal effects in high average power optical parametric amplifiers.

    Science.gov (United States)

    Rothhardt, Jan; Demmler, Stefan; Hädrich, Steffen; Peschel, Thomas; Limpert, Jens; Tünnermann, Andreas

    2013-03-01

    Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given.

  17. Eighth CW and High Average Power RF Workshop

    CERN Document Server

    2014-01-01

    We are pleased to announce the next Continuous Wave and High Average RF Power Workshop, CWRF2014, to take place at Hotel NH Trieste, Trieste, Italy from 13 to 16 May, 2014. This is the eighth in the CWRF workshop series and will be hosted by Elettra - Sincrotrone Trieste S.C.p.A. (www.elettra.eu). CWRF2014 will provide an opportunity for designers and users of CW and high average power RF systems to meet and interact in a convivial environment to share experiences and ideas on applications which utilize high-power klystrons, gridded tubes, combined solid-state architectures, high-voltage power supplies, high-voltage modulators, high-power combiners, circulators, cavities, power couplers and tuners. New ideas for high-power RF system upgrades and novel ways of RF power generation and distribution will also be discussed. CWRF2014 sessions will start on Tuesday morning and will conclude on Friday lunchtime. A visit to Elettra and FERMI will be organized during the workshop. ORGANIZING COMMITTEE (OC): Al...

  18. Average density and porosity of high-strength lightweight concrete

    Directory of Open Access Journals (Sweden)

    A.S. Inozemtcev

    2014-11-01

    Full Text Available The analysis results of high-strength lightweight concrete (HSLWC structure are presented in this paper. The X-ray tomography, optical microscopy and other methods are used for researching of average density and porosity. It has been revealed that mixtures of HSLWC with density 1300…1500 kg/m3 have a homogeneous structure. The developed concrete has a uniform distribution of the hollow filler and a uniform layer of cement-mineral matrix. The highly saturated gas phase which is divided by denser large particles of quartz sand and products of cement hydration in the contact area allow forming a composite material with low average density, big porosity (up to 40% and high strength (compressive strength is more than 40 MPa. Special modifiers increase adhesion, compacts structure in the contact area, decrease water absorption of high-strength lightweight concrete (up to 1 % and ensure its high water resistance (water resistance coefficient is more than 0.95.

  19. A high average power electro-optic switch using KTP

    Energy Technology Data Exchange (ETDEWEB)

    Ebbers, C.A.; Cook, W.M.; Velsko, S.P.

    1994-04-01

    High damage threshold, high thermal conductivity, and small thermo-optic coefficients make KTiOPO{sub 4} (KTP) an attractive material for use in a high average power Q-switch. However, electro-chromic damage and refractive index homogeneity have prevented the utilization of KTP in such a device in the past. This work shows that electro-chromic damage is effectively suppressed using capacitive coupling, and a KTP crystal can be Q-switched for 1.5 {times} 10{sup 9} shots without any detectable electro-chromic damage. In addition, KTP with the high uniformity and large aperture size needed for a KTP electro-optic Q-switch can be obtained from flux crystals grown at constant temperature. A thermally compensated, dual crystal KTP Q-switch, which successfully produced 50 mJ pulses with a pulse width of 8 ns (FWHM), has been constructed. In addition, in off-line testing the Q-switch showed less than 7% depolarization at an average power loading of 3.2 kW/cm{sup 2}.

  20. Code Red: Explaining Average Age of Death in the City of Hamilton

    Directory of Open Access Journals (Sweden)

    Patrick F. DeLuca

    2015-11-01

    Full Text Available The aim of this study is to identify the underlying factors that explain the average age of death in the City of Hamilton, Ontario, Canada, as identified in the Code Red Series of articles that were published in the city's local newspaper in 2010. Using a combination of data from the Canadian Census, the Government of Ontario and the Canadian Institute for Health Information, factor analysis was performed yielding three factors relating to poverty, working class, and health and aging. In a regression analysis these factors account for 42% of the total variability in the average ages of death observed at the census tract level of geography within the city.

  1. A high-average-power FEL for industrial applications

    Energy Technology Data Exchange (ETDEWEB)

    Dylla, H.F.; Benson, S.; Bisognano, J.

    1995-12-31

    CEBAF has developed a comprehensive conceptual design of an industrial user facility based on a kilowatt UV (150-1000 nm) and IR (2-25 micron) FEL driven by a recirculating, energy-recovering 200 MeV superconducting radio-frequency (SRF) accelerator. FEL users{endash}CEBAF`s partners in the Laser Processing Consortium, including AT&T, DuPont, IBM, Northrop-Grumman, 3M, and Xerox{endash}plan to develop applications such as polymer surface processing, metals and ceramics micromachining, and metal surface processing, with the overall effort leading to later scale-up to industrial systems at 50-100 kW. Representative applications are described. The proposed high-average-power FEL overcomes limitations of conventional laser sources in available power, cost-effectiveness, tunability and pulse structure. 4 refs., 3 figs., 2 tabs.

  2. Potential of high-average-power solid state lasers

    Energy Technology Data Exchange (ETDEWEB)

    Emmett, J.L.; Krupke, W.F.; Sooy, W.R.

    1984-09-25

    We discuss the possibility of extending solid state laser technology to high average power and of improving the efficiency of such lasers sufficiently to make them reasonable candidates for a number of demanding applications. A variety of new design concepts, materials, and techniques have emerged over the past decade that, collectively, suggest that the traditional technical limitations on power (a few hundred watts or less) and efficiency (less than 1%) can be removed. The core idea is configuring the laser medium in relatively thin, large-area plates, rather than using the traditional low-aspect-ratio rods or blocks. This presents a large surface area for cooling, and assures that deposited heat is relatively close to a cooled surface. It also minimizes the laser volume distorted by edge effects. The feasibility of such configurations is supported by recent developments in materials, fabrication processes, and optical pumps. Two types of lasers can, in principle, utilize this sheet-like gain configuration in such a way that phase and gain profiles are uniformly sampled and, to first order, yield high-quality (undistorted) beams. The zig-zag laser does this with a single plate, and should be capable of power levels up to several kilowatts. The disk laser is designed around a large number of plates, and should be capable of scaling to arbitrarily high power levels.

  3. HIGH AVERAGE POWER UV FREE ELECTRON LASER EXPERIMENTS AT JLAB

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, David; Evtushenko, Pavel; Gubeli, Joseph; Hernandez-Garcia, Carlos; Legg, Robert; Neil, George; Powers, Thomas; Shinn, Michelle D; Tennant, Christopher

    2012-07-01

    Having produced 14 kW of average power at {approx}2 microns, JLAB has shifted its focus to the ultraviolet portion of the spectrum. This presentation will describe the JLab UV Demo FEL, present specifics of its driver ERL, and discuss the latest experimental results from FEL experiments and machine operations.

  4. Average use of Alcohol and Binge Drinking in Pregnancy: Neuropsychological Effects at Age 5

    DEFF Research Database (Denmark)

    Kilburn, Tina R.

    Objectives The objective of this PhD. was to examine the relation between low weekly average maternal alcohol consumption and ‘Binge drinking' (defined as intake of 5 or more drinks per occasion) during pregnancy and information processing time (IPT) in children aged five years. Since a method...... to investigate IPT in very young children does not exist, it was decided to develop a method to test this based on Sternberg's paradigm. Method development Sternberg's original method of testing IPT used nine digits in a computer based program, where a subject had to decide whether a shown digit was found...... that provided detailed information on maternal alcohol drinking patterns before and during pregnancy and other lifestyle factors. These women were categorized in groups of prenatally average alcohol intake and binge drinking, timing and number of episodes. At the age of five years the children of these women...

  5. Picosecond mid-infrared amplifier for high average power.

    CSIR Research Space (South Africa)

    Botha, LR

    2007-04-01

    Full Text Available are similar. The saturation fluence for a multi level system can be written as z PhEsat σ υ 2 = With σ the stimulated emission cross section and P the pressure of the laser. 1/z... is essentially the average number of populated rotational levels. For our case z=0.07 and 181054.1 −×=σ cm2. Thus for a 10 atm laser the saturation fluence is: 2 18 1334 /1173 07.01017/12 10109.210626.6 cmmJxEsat = ××× ××× = − − The maximum...

  6. From CIE 2006 physiological model to improved age-dependent and average colorimetric observers.

    Science.gov (United States)

    Sarkar, Abhijit; Autrusseau, Florent; Viénot, Françoise; Le Callet, Patrick; Blondé, Laurent

    2011-10-01

    In the context of color perception on modern wide-gamut displays with narrowband spectral primaries, we performed a theoretical analysis on various aspects of physiological observers proposed by CIE TC 1-36 (CIEPO06). We allowed certain physiological factors to vary, which was not considered in the CIEPO06 framework. For example, we analyzed that the long-wave-sensitive (LWS) or medium-wave-sensitive (MWS) peak wavelength shift in the photopigment absorption spectra, a factor not modeled in CIEPO06, contributed more toward observer variability than some of the factors considered in the model. Further, we compared the color-matching functions derived from the CIEPO06 model and the CIE 10° standard colorimetric observer to the average observer data from three distinct subgroups of Stiles-Burch observers, formed on the basis of observer ages (22-23 years, 27-29 years, and 49-50 years). The errors in predicting the x(λ) and y(λ) color-matching functions of the intragroup average observers in the long-wave range and in the medium-wave range, respectively, were generally more in the case of the CIEPO06 model compared to the 10° standard colorimetric observer and manifested in both spectral and chromaticity space. In contrast, the short-wave-sensitive z₁₀(λ) function of the 10° standard colorimetric observer performed poorly compared to the CIEPO06 model for all three subgroups. Finally, a constrained nonlinear optimization on the CIEPO06 model outputs showed that a peak wavelength shift of photopigment density alone could not improve the model prediction errors at higher wavelengths. As an alternative, two optimized weighting functions for each of the LWS and MWS cone photopigment densities led to significant improvement in the prediction of intra-age-group average data for both the 22-23 year and 49-50 year age groups. We hypothesize that the assumption in the CIEPO06 model that the peak optical density of visual pigments does not vary with age is false and is

  7. Active cooling of pulse compression diffraction gratings for high energy, high average power ultrafast lasers.

    Science.gov (United States)

    Alessi, David A; Rosso, Paul A; Nguyen, Hoang T; Aasen, Michael D; Britten, Jerald A; Haefner, Constantin

    2016-12-26

    Laser energy absorption and subsequent heat removal from diffraction gratings in chirped pulse compressors poses a significant challenge in high repetition rate, high peak power laser development. In order to understand the average power limitations, we have modeled the time-resolved thermo-mechanical properties of current and advanced diffraction gratings. We have also developed and demonstrated a technique of actively cooling Petawatt scale, gold compressor gratings to operate at 600W of average power - a 15x increase over the highest average power petawatt laser currently in operation. Combining this technique with low absorption multilayer dielectric gratings developed in our group would enable pulse compressors for petawatt peak power lasers operating at average powers well above 40kW.

  8. Cesium telluride cathodes for the next generation of high-average current high-brightness photoinjectors

    Energy Technology Data Exchange (ETDEWEB)

    Filippetto, D., E-mail: dfilippetto@lbl.gov; Qian, H.; Sannibale, F. [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720 (United States)

    2015-07-27

    We report on the performances of a Cs{sub 2}Te photocathode under extreme conditions of high peak time-dependent accelerating fields, continuous wave operations, and MHz pulse extraction with up to 0.3 mA average current. The measurements, performed in a normal conducting cavity, show extended lifetime and robustness, elucidate the main mechanisms for cathode degradation, and set the required system vacuum performance for compatibility with the operations of a high average power X-ray free electron laser user facility, opening the doors to the next generation of MHz-scale ultrafast scientific instruments.

  9. Diode-Pumped High Energy and High Average Power All-Solid-State Picosecond Amplifier Systems

    OpenAIRE

    Jiaxing Liu; Wei Wang; Zhaohua Wang; Zhiguo Lv; Zhiyuan Zhang; Zhiyi Wei

    2015-01-01

    We present our research on the high energy picosecond laser operating at a repetition rate of 1 kHz and the high average power picosecond laser running at 100 kHz based on bulk Nd-doped crystals. With diode-pumped solid state (DPSS) hybrid amplifiers consisting of a picosecond oscillator, a regenerative amplifier, end-pumped single-pass amplifiers, and a side-pumped amplifier, an output energy of 64.8 mJ at a repetition rate of 1 kHz was achieved. An average power of 37.5 W at a repetition ra...

  10. Diode-Pumped High Energy and High Average Power All-Solid-State Picosecond Amplifier Systems

    Directory of Open Access Journals (Sweden)

    Jiaxing Liu

    2015-12-01

    Full Text Available We present our research on the high energy picosecond laser operating at a repetition rate of 1 kHz and the high average power picosecond laser running at 100 kHz based on bulk Nd-doped crystals. With diode-pumped solid state (DPSS hybrid amplifiers consisting of a picosecond oscillator, a regenerative amplifier, end-pumped single-pass amplifiers, and a side-pumped amplifier, an output energy of 64.8 mJ at a repetition rate of 1 kHz was achieved. An average power of 37.5 W at a repetition rate of 100 kHz pumped by continuous wave laser diodes was obtained. Compact, stable and high power DPSS laser amplifier systems with good beam qualities are excellent picosecond sources for high power optical parametric chirped pulse amplification (OPCPA and high-efficiency laser processing.

  11. High average power coherent vuv generation at 10 MHz repetition frequency by intracavity high harmonic generation.

    Science.gov (United States)

    Ozawa, Akira; Zhao, Zhigang; Kuwata-Gonokami, Makoto; Kobayashi, Yohei

    2015-06-15

    Intracavity high harmonic generation was utilized to generate high average-power coherent radiation at vacuum ultraviolet (vuv) wavelengths. A ytterbium-doped fiber-laser based master-oscillator power-amplifier (MOPA) system with a 10 MHz repetition frequency was developed and used as a driving laser for an external cavity. A series of odd-order harmonic radiations was generated extending down to ∼ 30 nm (41 eV in photon energy). The 7th harmonic radiation generated was centered at 149 nm and had an average output power of up to 0.5 mW. In this way, we developed a sub-mW coherent vuv-laser with a 10 MHz repetition frequency, which, if used as an excitation laser source for photo-electron spectroscopy, could improve the signal count-rate without deterioration of the spectral-resolution caused by space-charge effects.

  12. Crossatron switch as thyratron replacement in high repetition rate, high average power modulators

    Science.gov (United States)

    Sullivan, J. S.

    1988-06-01

    The Crossatron is a cold cathode, low pressure, gas discharge switch with opening and closing capabilities. Due to its cold cathode operation, the Crossatron may offer lifetime advantages compared to the hydrogen thyratron. Unfortunately, little information regarding Crossatron lifetime and performance in high repetition rate, high average power, pulse modulators exists. Four prototype Crossatron devices, fabricated by Hughes Aircraft, were obtained to evaluate their performance and lifetime in high repetition rate, high average power, pulse modulators that had previously been equipped with hydrogen thyratrons. The prototype Crossatrons were evaluated over a range of operating parameters. Various grid drive, keep alive power levels and triggering schemes were employed in the tests. Switch parameters such as trigger time, anode fall time, jitter, recovery time, peak di/dt, switch efficiency, and the gas pumping effect of the discharge were observed. One Crossatron prototype was also subjected to lifetime tests that accumulated tens of billions of pulses. Lifetime data will be compared to various thyratron models tested similarly.

  13. High-throughput machining using high average power ultrashort pulse lasers and ultrafast polygon scanner

    Science.gov (United States)

    Schille, Joerg; Schneider, Lutz; Streek, André; Kloetzer, Sascha; Loeschner, Udo

    2016-03-01

    In this paper, high-throughput ultrashort pulse laser machining is investigated on various industrial grade metals (Aluminium, Copper, Stainless steel) and Al2O3 ceramic at unprecedented processing speeds. This is achieved by using a high pulse repetition frequency picosecond laser with maximum average output power of 270 W in conjunction with a unique, in-house developed two-axis polygon scanner. Initially, different concepts of polygon scanners are engineered and tested to find out the optimal architecture for ultrafast and precision laser beam scanning. Remarkable 1,000 m/s scan speed is achieved on the substrate, and thanks to the resulting low pulse overlap, thermal accumulation and plasma absorption effects are avoided at up to 20 MHz pulse repetition frequencies. In order to identify optimum processing conditions for efficient high-average power laser machining, the depths of cavities produced under varied parameter settings are analyzed and, from the results obtained, the characteristic removal values are specified. The maximum removal rate is achieved as high as 27.8 mm3/min for Aluminium, 21.4 mm3/min for Copper, 15.3 mm3/min for Stainless steel and 129.1 mm3/min for Al2O3 when full available laser power is irradiated at optimum pulse repetition frequency.

  14. The development of early numeracy skills in kindergarten in low-, average- and high-performance groups

    NARCIS (Netherlands)

    Aunio, P.; Heiskari, P.; van Luit, J.E.H.; Vuorio, J.-M.

    2015-01-01

    In this study, we investigated how early numeracy skills develop in kindergarten-age children. The participants were 235 Finnish children (111 girls and 124 boys). At the time of the first measurement, the average age of the children was 6 years. The measurements were conducted three times during 1

  15. Current long-term negative average annual energy balance of the earth leads to the new little ice age

    Directory of Open Access Journals (Sweden)

    Abdussamatov Habibullo

    2015-01-01

    Full Text Available The average annual decreasing rate of the total solar irradiance (TSI is increasing from the 22-nd to the 23-rd and 24-th cycles, because the Sun since the 1990 is in the phase decline of quasi-bicentennial variation. The portion of the solar energy absorbed by the Earth is decreasing. Decrease in the portion of TSI absorbed by the Earth since 1990 remains uncompensated by the Earth's radiation into space at the previous high level over a time interval determined by the thermal inertia of the Ocean. A long-term negative deviation of the Earth’s average annual energy balance from the equilibrium state is dictating corresponding variations in it’s the energy state. As a result, the Earth will have a negative average annual energy balance also in the future. This will lead to the beginning of the decreasing in the Earth's temperature and of the epoch of the Little Ice Age after the maximum phase of the 24-th solar cycle approximately since the end of 2014. The influence of the consecutive chain of the secondary feedback effects (the increase in the Bond albedo and the decrease in the concentration of greenhouse gases in the atmosphere due to cooling will lead to an additional reduction of the absorbed solar energy and reduce the greenhouse effect. The start of the TSI’s Grand Minimum is anticipated in the solar cycle 27±1 in 2043±11 and the beginning of the phase of deep cooling of the 19th Little Ice Age for the past 7,500 years around 2060±11.

  16. Hard Water or High Ages?

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2008-01-01

    to spurious, too high ages of samples from freshwater systems. The possibility of the hardwater effect in food crusts on pottery is investigated for two sites of the Late Mesolithic Ertebølle culture. The first radiocarbon dates from the food crusts from these sites were surprisingly high. I will examine...

  17. High-gain Yb:YAG amplifier for ultrashort pulse laser at high-average power

    Science.gov (United States)

    Vetrovec, John; Copeland, Drew A.; Litt, Amardeep S.; Du, Detao

    2016-03-01

    We report on a Yb:YAG laser amplifier for ultrashort pulse applications at kW-class average power. The laser uses two large-aperture, disk-type gain elements fabricated from composite ceramic YAG material, and a multi-pass extraction architecture to obtain high gain in a chirped-pulse amplification system. The disks are edge-pumped, thus allowing for reduced doping of host material with laser ions, which translates to lower lasing threshold and lower heat dissipation in the Yb:YAG material. The latter makes it possible to amplify a near diffraction-limited seed without significant thermo-optical distortions. This work presents results of testing the laser amplifier with relay optics configured for energy extraction with up to 40 passes through the disks. Applications for the ultrashort pulse laser amplifier include producing laser-induced plasma channel, laser material ablation, and laser acceleration of atomic particles.

  18. Icodextrin improves metabolic and fluid management in high and high-average transport diabetic patients.

    Science.gov (United States)

    Paniagua, Ramón; Ventura, María-de-Jesús; Avila-Díaz, Marcela; Cisneros, Alejandra; Vicenté-Martínez, Marlén; Furlong, María-Del-Carmen; García-González, Zuzel; Villanueva, Diana; Orihuela, Oscar; Prado-Uribe, María-Del-Carmen; Alcántara, Guadalupe; Amato, Dante

    2009-01-01

    Icodextrin-based solutions (ICO) have clinical and theoretical advantages over glucose-based solutions (GLU) in fluid and metabolic management of diabetic peritoneal dialysis (PD) patients; however, these advantages have not yet been tested in a randomized fashion. To analyze the effects of ICO on metabolic and fluid control in high and high-average transport diabetic patients on continuous ambulatory PD (CAPD). A 12-month, multicenter, open-label, randomized controlled trial was conducted to compare ICO (n = 30) versus GLU (n = 29) in diabetic CAPD patients with high-average and high peritoneal transport characteristics. The basic daily schedule was 3 x 2 L GLU (1.5%) and either 1 x 2 L ICO (7.5%) or 1 x 2 L GLU (2.5%) for the long-dwell exchange, with substitution of 2.5% or 4.25% for 1.5% GLU being allowed when clinically necessary. Variables related to metabolic and fluid control were measured each month. Groups were similar at baseline in all measured variables. More than 66% of the patients using GLU, but only 9% using ICO, needed prescriptions of higher glucose concentration solutions. Ultrafiltration (UF) was higher (198 +/- 101 mL/day, p ICO group than in the GLU group over time. Changes from baseline were more pronounced in the ICO group than in the GLU group for extracellular fluid volume (0.23 +/- 1.38 vs -1.0 +/- 1.48 L, p ICO group had better metabolic control than those in the GLU group: glucose absorption was more reduced (-17 +/- 44 vs -64 +/- 35 g/day) as were insulin needs (3.6 +/- 3.4 vs - 9.1 +/- 4.7 U/day, p ICO group had fewer adverse events related to fluid and glucose control than patients in the GLU group. Icodextrin represents a significant advantage in the management of high transport diabetic patients on PD, improving peritoneal UF and fluid control and reducing the burden of glucose overexposure, thereby facilitating metabolic control.

  19. Average Transient Lifetime and Lyapunov Dimension for Transient Chaos in a High-Dimensional System

    Institute of Scientific and Technical Information of China (English)

    陈洪; 汤建新; 唐少炎; 向红; 陈新

    2001-01-01

    The average transient lifetime of a chaotic transient versus the Lyapunov dimension of a chaotic saddle is studied for high-dimensional nonlinear dynamical systems. Typically the average lifetime depends upon not only the system parameter but also the Lyapunov dimension of the chaotic saddle. The numerical example uses the delayed feedback differential equation.

  20. Vibrational resonance: a study with high-order word-series averaging

    CERN Document Server

    Murua, Ander

    2016-01-01

    We study a model problem describing vibrational resonance by means of a high-order averaging technique based on so-called word series. With the tech- nique applied here, the tasks of constructing the averaged system and the associ- ated change of variables are divided into two parts. It is first necessary to build recursively a set of so-called word basis functions and, after that, all the required manipulations involve only scalar coefficients that are computed by means of sim- ple recursions. As distinct from the situation with other approaches, with word- series, high-order averaged systems may be derived without having to compute the associated change of variables. In the system considered here, the construction of high-order averaged systems makes it possible to obtain very precise approxima- tions to the true dynamics.

  1. The Analysis of Average Diameter of Erythrocytes in Children of Early Age with Pneumonia and Acute Respiratory Viral Infections

    Directory of Open Access Journals (Sweden)

    S. S. Shevchenko,

    2015-01-01

    Full Text Available Development of inflammatory bronkholegochny process in children is followed by the permanent changes in system of an eritron aggravating finally the phenomena of a hypoxia of bodies and fabrics. Work purpose: studying of average diameter of erythrocytes at children of early age, patients with pneumonia and ARVI. Determination of average diameter of erythrocytes was carried out by a diffraction method on identical structure of chaotic objects at 36 children with pneumonia and at 41 children with a ARVI aged from 4 months till 3 years. The control group was made by 20 almost healthy children of the same age. During the sharp period of a disease the average diameter of erythrocytes was authentically increased both at pneumonia, and at a ARVI. Reliable difference of these indicators when comparing a toxic syndrome at pneumonia and a ARVI is revealed. Thus, at children of early age, patients with pneumonia and ARVI, in dynamics of a disease the natural changes of average diameter of erythrocytes having differential and diagnostic and predictive value are revealed.

  2. Improved performance of high average power semiconductor arrays for applications in diode pumped solid state lasers

    Energy Technology Data Exchange (ETDEWEB)

    Beach, R.; Emanuel, M.; Benett, W.; Freitas, B.; Ciarlo, D.; Carlson, N.; Sutton, S.; Skidmore, J.; Solarz, R.

    1994-01-01

    The average power performance capability of semiconductor diode laser arrays has improved dramatically over the past several years. These performance improvements, combined with cost reductions pursued by LLNL and others in the fabrication and packaging of diode lasers, have continued to reduce the price per average watt of laser diode radiation. Presently, we are at the point where the manufacturers of commercial high average power solid state laser systems used in material processing applications can now seriously consider the replacement of their flashlamp pumps with laser diode pump sources. Additionally, a low cost technique developed and demonstrated at LLNL for optically conditioning the output radiation of diode laser arrays has enabled a new and scalable average power diode-end-pumping architecture that can be simply implemented in diode pumped solid state laser systems (DPSSL`s). This development allows the high average power DPSSL designer to look beyond the Nd ion for the first time. Along with high average power DPSSL`s which are appropriate for material processing applications, low and intermediate average power DPSSL`s are now realizable at low enough costs to be attractive for use in many medical, electronic, and lithographic applications.

  3. Validity of a Wearable Accelerometer Device to Measure Average Acceleration Values During High-Speed Running.

    Science.gov (United States)

    Alexander, Jeremy P; Hopkinson, Trent L; Wundersitz, Daniel W T; Serpell, Benjamin G; Mara, Jocelyn K; Ball, Nick B

    2016-11-01

    Alexander, JP, Hopkinson, TL, Wundersitz, DWT, Serpell, BG, Mara, JK, and Ball, NB. Validity of a wearable accelerometer device to measure average acceleration values during high-speed running. J Strength Cond Res 30(11): 3007-3013, 2016-The aim of this study was to determine the validity of an accelerometer to measure average acceleration values during high-speed running. Thirteen subjects performed three sprint efforts over a 40-m distance (n = 39). Acceleration was measured using a 100-Hz triaxial accelerometer integrated within a wearable tracking device (SPI-HPU; GPSports). To provide a concurrent measure of acceleration, timing gates were positioned at 10-m intervals (0-40 m). Accelerometer data collected during 0-10 m and 10-20 m provided a measure of average acceleration values. Accelerometer data was recorded as the raw output and filtered by applying a 3-point moving average and a 10-point moving average. The accelerometer could not measure average acceleration values during high-speed running. The accelerometer significantly overestimated average acceleration values during both 0-10 m and 10-20 m, regardless of the data filtering technique (p < 0.001). Body mass significantly affected all accelerometer variables (p < 0.10, partial η = 0.091-0.219). Body mass and the absence of a gravity compensation formula affect the accuracy and practicality of accelerometers. Until GPSports-integrated accelerometers incorporate a gravity compensation formula, the usefulness of any accelerometer-derived algorithms is questionable.

  4. Aging underdamped scaled Brownian motion: Ensemble- and time-averaged particle displacements, nonergodicity, and the failure of the overdamping approximation

    Science.gov (United States)

    Safdari, Hadiseh; Cherstvy, Andrey G.; Chechkin, Aleksei V.; Bodrova, Anna; Metzler, Ralf

    2017-01-01

    We investigate both analytically and by computer simulations the ensemble- and time-averaged, nonergodic, and aging properties of massive particles diffusing in a medium with a time dependent diffusivity. We call this stochastic diffusion process the (aging) underdamped scaled Brownian motion (UDSBM). We demonstrate how the mean squared displacement (MSD) and the time-averaged MSD of UDSBM are affected by the inertial term in the Langevin equation, both at short, intermediate, and even long diffusion times. In particular, we quantify the ballistic regime for the MSD and the time-averaged MSD as well as the spread of individual time-averaged MSD trajectories. One of the main effects we observe is that, both for the MSD and the time-averaged MSD, for superdiffusive UDSBM the ballistic regime is much shorter than for ordinary Brownian motion. In contrast, for subdiffusive UDSBM, the ballistic region extends to much longer diffusion times. Therefore, particular care needs to be taken under what conditions the overdamped limit indeed provides a correct description, even in the long time limit. We also analyze to what extent ergodicity in the Boltzmann-Khinchin sense in this nonstationary system is broken, both for subdiffusive and superdiffusive UDSBM. Finally, the limiting case of ultraslow UDSBM is considered, with a mixed logarithmic and power-law dependence of the ensemble- and time-averaged MSDs of the particles. In the limit of strong aging, remarkably, the ordinary UDSBM and the ultraslow UDSBM behave similarly in the short time ballistic limit. The approaches developed here open ways for considering other stochastic processes under physically important conditions when a finite particle mass and aging in the system cannot be neglected.

  5. Preparation of high viscosity average molecular mass poly-L-lactide

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhi-hua; RUAN Jian-ming; ZOU Jian-peng; ZHOU Zhong-cheng; SHEN Xiong-jun

    2006-01-01

    Poly-L-lactide(PLLA) was synthesized by ring-opening polymerization from high purity L-lactide with tin octoate as initiator, and characterized by means of infrared, and 1H-nuclear magnetic resonance. The influences of initiator concentration,polymerization temperature and polymerization time on the viscosity average molecular mass of PLLA were investigated. The effects of different purification methods on the concentration of initiator and viscosity average molecular mass were also studied. PLLA with a viscosity average molecular mass of about 50.5×104 was obtained when polymerization was conducted for 24 h at 140 ℃ with the molar ratio of monomer to purification initator being 12 000. After purification, the concentration of tin octoate decreases; however,the effect of different purification methods on the viscosity average molecular mass of PLLA is different, and the obtained PLLA is a typical amorphous polymeric material. The crystallinity of PLLA decreases with the increase of viscosity average molecular mass.

  6. Performance and production requirements for the optical components in a high-average-power laser system

    Energy Technology Data Exchange (ETDEWEB)

    Chow, R.; Doss, F.W.; Taylor, J.R.; Wong, J.N.

    1999-07-02

    Optical components needed for high-average-power lasers, such as those developed for Atomic Vapor Laser Isotope Separation (AVLIS), require high levels of performance and reliability. Over the past two decades, optical component requirements for this purpose have been optimized and performance and reliability have been demonstrated. Many of the optical components that are exposed to the high power laser light affect the quality of the beam as it is transported through the system. The specifications for these optics are described including a few parameters not previously reported and some component manufacturing and testing experience. Key words: High-average-power laser, coating efficiency, absorption, optical components

  7. High-throughput machining using a high-average power ultrashort pulse laser and high-speed polygon scanner

    Science.gov (United States)

    Schille, Joerg; Schneider, Lutz; Streek, André; Kloetzer, Sascha; Loeschner, Udo

    2016-09-01

    High-throughput ultrashort pulse laser machining is investigated on various industrial grade metals (aluminum, copper, and stainless steel) and Al2O3 ceramic at unprecedented processing speeds. This is achieved by using a high-average power picosecond laser in conjunction with a unique, in-house developed polygon mirror-based biaxial scanning system. Therefore, different concepts of polygon scanners are engineered and tested to find the best architecture for high-speed and precision laser beam scanning. In order to identify the optimum conditions for efficient processing when using high-average laser powers, the depths of cavities made in the samples by varying the processing parameter settings are analyzed and, from the results obtained, the characteristic removal values are specified. For overlapping pulses of optimum fluence, the removal rate is as high as 27.8 mm3/min for aluminum, 21.4 mm3/min for copper, 15.3 mm3/min for stainless steel, and 129.1 mm3/min for Al2O3, when a laser beam of 187 W average laser powers irradiates. On stainless steel, it is demonstrated that the removal rate increases to 23.3 mm3/min when the laser beam is very fast moving. This is thanks to the low pulse overlap as achieved with 800 m/s beam deflection speed; thus, laser beam shielding can be avoided even when irradiating high-repetitive 20-MHz pulses.

  8. Crimes and the Bell Curve: The Role of People with High, Average, and Low Intelligence

    OpenAIRE

    Burhan, Nik Ahmad Sufian; Kurniawan, Yohan; Sidek, Abdul Halim; Mohamad, Mohd Rosli

    2014-01-01

    The present study examines whether crime rates can be reduced by increasing the IQ of people with high, average, and low IQ. Previous studies have shown that as a determinant of the national level of income per capita growth and technological achievement, the IQ of the intellectual class (those at the 95th percentile of the Bell curve distribution of population intelligence) is more important than the IQ of those with average ability at the 50th percentile. Extending these findings, our study...

  9. Development of a high average current polarized electron source with long cathode operational lifetime

    Energy Technology Data Exchange (ETDEWEB)

    C. K. Sinclair; P. A. Adderley; B. M. Dunham; J. C. Hansknecht; P. Hartmann; M. Poelker; J. S. Price; P. M. Rutt; W. J. Schneider; M. Steigerwald

    2007-02-01

    Substantially more than half of the electromagnetic nuclear physics experiments conducted at the Continuous Electron Beam Accelerator Facility of the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory) require highly polarized electron beams, often at high average current. Spin-polarized electrons are produced by photoemission from various GaAs-based semiconductor photocathodes, using circularly polarized laser light with photon energy slightly larger than the semiconductor band gap. The photocathodes are prepared by activation of the clean semiconductor surface to negative electron affinity using cesium and oxidation. Historically, in many laboratories worldwide, these photocathodes have had short operational lifetimes at high average current, and have often deteriorated fairly quickly in ultrahigh vacuum even without electron beam delivery. At Jefferson Lab, we have developed a polarized electron source in which the photocathodes degrade exceptionally slowly without electron emission, and in which ion back bombardment is the predominant mechanism limiting the operational lifetime of the cathodes during electron emission. We have reproducibly obtained cathode 1/e dark lifetimes over two years, and 1/e charge density and charge lifetimes during electron beam delivery of over 2?105???C/cm2 and 200 C, respectively. This source is able to support uninterrupted high average current polarized beam delivery to three experimental halls simultaneously for many months at a time. Many of the techniques we report here are directly applicable to the development of GaAs photoemission electron guns to deliver high average current, high brightness unpolarized beams.

  10. High-Average-Power Diffraction Pulse-Compression Gratings Enabling Next-Generation Ultrafast Laser Systems

    Energy Technology Data Exchange (ETDEWEB)

    Alessi, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-11-01

    Pulse compressors for ultrafast lasers have been identified as a technology gap in the push towards high peak power systems with high average powers for industrial and scientific applications. Gratings for ultrashort (sub-150fs) pulse compressors are metallic and can absorb a significant percentage of laser energy resulting in up to 40% loss as well as thermal issues which degrade on-target performance. We have developed a next generation gold grating technology which we have scaled to the petawatt-size. This resulted in improvements in efficiency, uniformity and processing as compared to previous substrate etched gratings for high average power. This new design has a deposited dielectric material for the grating ridge rather than etching directly into the glass substrate. It has been observed that average powers as low as 1W in a compressor can cause distortions in the on-target beam. We have developed and tested a method of actively cooling diffraction gratings which, in the case of gold gratings, can support a petawatt peak power laser with up to 600W average power. We demonstrated thermo-mechanical modeling of a grating in its use environment and benchmarked with experimental measurement. Multilayer dielectric (MLD) gratings are not yet used for these high peak power, ultrashort pulse durations due to their design challenges. We have designed and fabricated broad bandwidth, low dispersion MLD gratings suitable for delivering 30 fs pulses at high average power. This new grating design requires the use of a novel Out Of Plane (OOP) compressor, which we have modeled, designed, built and tested. This prototype compressor yielded a transmission of 90% for a pulse with 45 nm bandwidth, and free of spatial and angular chirp. In order to evaluate gratings and compressors built in this project we have commissioned a joule-class ultrafast Ti:Sapphire laser system. Combining the grating cooling and MLD technologies developed here could enable petawatt laser systems to

  11. Free-space optical communications with peak and average constraints: High SNR capacity approximation

    KAUST Repository

    Chaaban, Anas

    2015-09-07

    The capacity of the intensity-modulation direct-detection (IM-DD) free-space optical channel with both average and peak intensity constraints is studied. A new capacity lower bound is derived by using a truncated-Gaussian input distribution. Numerical evaluation shows that this capacity lower bound is nearly tight at high signal-to-noise ratio (SNR), while it is shown analytically that the gap to capacity upper bounds is a small constant at high SNR. In particular, the gap to the high-SNR asymptotic capacity of the channel under either a peak or an average constraint is small. This leads to a simple approximation of the high SNR capacity. Additionally, a new capacity upper bound is derived using sphere-packing arguments. This bound is tight at high SNR for a channel with a dominant peak constraint.

  12. Problem-Solving Processes of High and Average Performers in Physics.

    Science.gov (United States)

    Coleman, Elaine B.; Shore, Bruce

    1991-01-01

    This study examined the problem-solving protocols of 21 students in a grade 11 enriched physics course as well as 3 adult "experts" in physics. Experts and high performing students made more correct metastatements and more references to prior knowledge than did average performing students. (DB)

  13. Total Quality Management (TQM) Practices and School Climate amongst High, Average and Low Performance Secondary Schools

    Science.gov (United States)

    Ismail, Siti Noor

    2014-01-01

    Purpose: This study attempted to determine whether the dimensions of TQM practices are predictors of school climate. It aimed to identify the level of TQM practices and school climate in three different categories of schools, namely high, average and low performance schools. The study also sought to examine which dimensions of TQM practices…

  14. High-frequency averaging in semi-classical Hartree-type equations

    CERN Document Server

    Giannoulis, Johannes; Sparber, Christof

    2009-01-01

    We investigate the asymptotic behavior of solutions to semi-classical Schroedinger equations with nonlinearities of Hartree type. For a weakly nonlinear scaling, we show the validity of an asymptotic superposition principle for slowly modulated highly oscillatory pulses. The result is based on a high-frequency averaging effect due to the nonlocal nature of the Hartree potential, which inhibits the creation of new resonant waves. In the proof we make use of the framework of Wiener algebras.

  15. Population Aging at Cross-Roads: Diverging Secular Trends in Average Cognitive Functioning and Physical Health in the Older Population of Germany.

    Science.gov (United States)

    Steiber, Nadia

    2015-01-01

    This paper uses individual-level data from the German Socio-Economic Panel to model trends in population health in terms of cognition, physical fitness, and mental health between 2006 and 2012. The focus is on the population aged 50-90. We use a repeated population-based cross-sectional design. As outcome measures, we use SF-12 measures of physical and mental health and the Symbol-Digit Test (SDT) that captures cognitive processing speed. In line with previous research we find a highly significant Flynn effect on cognition; i.e., SDT scores are higher among those who were tested more recently (at the same age). This result holds for men and women, all age groups, and across all levels of education. While we observe a secular improvement in terms of cognitive functioning, at the same time, average physical and mental health has declined. The decline in average physical health is shown to be stronger for men than for women and found to be strongest for low-educated, young-old men aged 50-64: the decline over the 6-year interval in average physical health is estimated to amount to about 0.37 SD, whereas average fluid cognition improved by about 0.29 SD. This pattern of results at the population-level (trends in average population health) stands in interesting contrast to the positive association of physical health and cognitive functioning at the individual-level. The findings underscore the multi-dimensionality of health and the aging process.

  16. Population Aging at Cross-Roads: Diverging Secular Trends in Average Cognitive Functioning and Physical Health in the Older Population of Germany.

    Directory of Open Access Journals (Sweden)

    Nadia Steiber

    Full Text Available This paper uses individual-level data from the German Socio-Economic Panel to model trends in population health in terms of cognition, physical fitness, and mental health between 2006 and 2012. The focus is on the population aged 50-90. We use a repeated population-based cross-sectional design. As outcome measures, we use SF-12 measures of physical and mental health and the Symbol-Digit Test (SDT that captures cognitive processing speed. In line with previous research we find a highly significant Flynn effect on cognition; i.e., SDT scores are higher among those who were tested more recently (at the same age. This result holds for men and women, all age groups, and across all levels of education. While we observe a secular improvement in terms of cognitive functioning, at the same time, average physical and mental health has declined. The decline in average physical health is shown to be stronger for men than for women and found to be strongest for low-educated, young-old men aged 50-64: the decline over the 6-year interval in average physical health is estimated to amount to about 0.37 SD, whereas average fluid cognition improved by about 0.29 SD. This pattern of results at the population-level (trends in average population health stands in interesting contrast to the positive association of physical health and cognitive functioning at the individual-level. The findings underscore the multi-dimensionality of health and the aging process.

  17. Development of a high average current polarized electron source with long cathode operational lifetime

    Directory of Open Access Journals (Sweden)

    C. K. Sinclair

    2007-02-01

    Full Text Available Substantially more than half of the electromagnetic nuclear physics experiments conducted at the Continuous Electron Beam Accelerator Facility of the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory require highly polarized electron beams, often at high average current. Spin-polarized electrons are produced by photoemission from various GaAs-based semiconductor photocathodes, using circularly polarized laser light with photon energy slightly larger than the semiconductor band gap. The photocathodes are prepared by activation of the clean semiconductor surface to negative electron affinity using cesium and oxidation. Historically, in many laboratories worldwide, these photocathodes have had short operational lifetimes at high average current, and have often deteriorated fairly quickly in ultrahigh vacuum even without electron beam delivery. At Jefferson Lab, we have developed a polarized electron source in which the photocathodes degrade exceptionally slowly without electron emission, and in which ion back bombardment is the predominant mechanism limiting the operational lifetime of the cathodes during electron emission. We have reproducibly obtained cathode 1/e dark lifetimes over two years, and 1/e charge density and charge lifetimes during electron beam delivery of over 2×10^{5}   C/cm^{2} and 200 C, respectively. This source is able to support uninterrupted high average current polarized beam delivery to three experimental halls simultaneously for many months at a time. Many of the techniques we report here are directly applicable to the development of GaAs photoemission electron guns to deliver high average current, high brightness unpolarized beams.

  18. Prevalence of colorectal adenoma in an average-risk population aged 40-50 versus 50-60 years.

    Science.gov (United States)

    Hemmasi, Gholamreza; Sohrabi, Masoudreza; Zamani, Farhad; Ajdarkosh, Hossein; Rakhshani, Naser; Khoonsari, Mahmoodreza; Ameli, Mitra; Hatami, Khadijeh

    2015-09-01

    According to current guidelines, screening colonoscopy begins at 50 years for the average-risk population, although there are not enough data on the incidence of precancerous lesions of individuals in the preceding decades. To evaluate the prevalence of colorectal polyps including potentially premalignant lesions in asymptomatic, average-risk individuals aged 40-49 versus 50-59 years, we offered total colonoscopy screening to individuals without any lower gastrointestinal symptoms. The primary end point was the prevalence of colorectal adenoma in two age groups. Of a total of 737 studies, 333 participants were 40-49 years old and 407 participants were 50-59 years old. The overall prevalence of adenomas was 11.2 and 16.4% in the group of 40-49 and 50-59 year olds, respectively. Advanced adenoma was more common in 50-59 year olds (1.2 vs. 2.9%). Malignancy was not reported in these groups. Furthermore, 77.5 and 68.6% of adenomas were observed in the distal colon in the groups of 40-49 year olds and 50-59 year olds, whereas in the proximal colon, 22.2 and 57.1% of adenomas in the groups of 40-49 year olds and 50-59 year olds, respectively, were advanced adenomas. In our study, male sex showed an association with adenoma. However, importantly, there was no significant association between age and colorectal adenoma. Although the prevalence of colorectal adenoma was similar in the two age groups investigated, the rate of advanced adenoma was higher in the group of individuals who were 50-59 years old, suggesting that colorectal cancer screening could be recommended at an age younger than 50 years.

  19. Kilowatt high average power narrow-linewidth nanosecond all-fiber laser

    Institute of Scientific and Technical Information of China (English)

    Rongtao; Su; Pu; Zhou; Xiaolin; Wang; Rumao; Tao; Xiaojun; Xu

    2014-01-01

    A high power narrow-linewidth nanosecond all-fiber laser based on the master oscillator power amplifier(MOPA)configuration is demonstrated. A pulsed seed with high repetition rate of 10 MHz was generated by modulating a continuous-wave(CW) single-frequency fiber laser at ~1064 nm by using an electro-optic intensity modulator(EOIM).After multi-stage cascaded power amplification, the average power was boosted to be kilowatt level. The pulses from the main amplifier had a pulse width of ~3 ns and an average/peak power of 913 W/28.6 kW. Further power scaling of the pulses was limited by stimulated Raman scattering(SRS) for the moment, method for SRS suppression and further power scaling was briefly discussed.

  20. Temperature-insensitive frequency tripling for generating high-average power UV lasers.

    Science.gov (United States)

    Zhong, Haizhe; Yuan, Peng; Wen, Shuangchun; Qian, Liejia

    2014-02-24

    Aimed for generating high-average power ultraviolet (UV) lasers via third-harmonic generation (THG) consisting of frequency doubling and tripling stages, we numerically and experimentally demonstrate a novel frequency tripling scheme capable of supporting temperature-insensitive phase-matching (PM). Two cascaded tripling crystals, with opposite signs of the temperature derivation of phase-mismatch, are proposed and theoretically studied for improving the temperature-acceptance of PM. The proof-of-principle tripling experiment using two crystals of LBO and BBO shows that the temperature acceptance can be ~1.5 times larger than that of using a single tripling crystal. In addition, the phase shift caused by air dispersion, along with its influence on the temperature-insensitive PM, are also discussed. To illustrate the potential applications of proposed two-crystal tripling design in the high-average-power regime, full numerical simulations for the tripling process, are implemented based on the realistic crystals. The demonstrated two-crystal tripling scheme may provide a promising route to high-average-power THG in the UV region.

  1. High speed laser drilling of metals using a high repetition rate, high average power ultrafast fiber CPA system.

    Science.gov (United States)

    Ancona, A; Röser, F; Rademaker, K; Limpert, J; Nolte, S; Tünnermann, A

    2008-06-09

    We present an experimental study on the drilling of metal targets with ultrashort laser pulses at high repetition rates (from 50 kHz up to 975 kHz) and high average powers (up to 68 Watts), using an ytterbium-doped fiber CPA system. The number of pulses to drill through steel and copper sheets with thicknesses up to 1 mm have been measured as a function of the repetition rate and the pulse energy. Two distinctive effects, influencing the drilling efficiency at high repetition rates, have been experimentally found and studied: particle shielding and heat accumulation. While the shielding of subsequent pulses due to the ejected particles leads to a reduced ablation efficiency, this effect is counteracted by heat accumulation. The experimental data are in good qualitative agreement with simulations of the heat accumulation effect and previous studies on the particle emission. However, for materials with a high thermal conductivity as copper, both effects are negligible for the investigated processing parameters. Therefore, the full power of the fiber CPA system can be exploited, which allows to trepan high-quality holes in 0.5mm-thick copper samples with breakthrough times as low as 75 ms.

  2. High energy, high average power solid state green or UV laser

    Science.gov (United States)

    Hackel, Lloyd A.; Norton, Mary; Dane, C. Brent

    2004-03-02

    A system for producing a green or UV output beam for illuminating a large area with relatively high beam fluence. A Nd:glass laser produces a near-infrared output by means of an oscillator that generates a high quality but low power output and then multi-pass through and amplification in a zig-zag slab amplifier and wavefront correction in a phase conjugator at the midway point of the multi-pass amplification. The green or UV output is generated by means of conversion crystals that follow final propagation through the zig-zag slab amplifier.

  3. High average power picosecond pulse generation from a thulium-doped all-fiber MOPA system.

    Science.gov (United States)

    Liu, Jiang; Wang, Qian; Wang, Pu

    2012-09-24

    We report a stable highly-integrated high power picosecond thulium-doped all-fiber MOPA system without using conventional chirped pulse amplification technique. The master oscillator was passively mode-locked by a SESAM to generate average power of 15 mW at a fundamental repetition rate of 103 MHz in a short linear cavity, and a uniform narrow bandwidth FBG is employed to stabilize the passively mode-locked laser operation. Two-stage double-clad thulium-doped all-fiber amplifiers were used directly to boost average power to 20.7 W. The laser center wavelength was 1962.8 nm and the pulse width was 18 ps. The single pulse energy and peak-power after the amplication were 200 nJ and 11.2 kW respectively. To the best of our knowledge, this is the highest average power ever reported for a picosecond thulium-doped all-fiber MOPA system.

  4. Incidence Rates of Clinical Mastitis among Canadian Holsteins Classified as High, Average, or Low Immune Responders

    Science.gov (United States)

    Miglior, Filippo; Mallard, Bonnie A.

    2013-01-01

    The objective of this study was to compare the incidence rate of clinical mastitis (IRCM) between cows classified as high, average, or low for antibody-mediated immune responses (AMIR) and cell-mediated immune responses (CMIR). In collaboration with the Canadian Bovine Mastitis Research Network, 458 lactating Holsteins from 41 herds were immunized with a type 1 and a type 2 test antigen to stimulate adaptive immune responses. A delayed-type hypersensitivity test to the type 1 test antigen was used as an indicator of CMIR, and serum antibody of the IgG1 isotype to the type 2 test antigen was used for AMIR determination. By using estimated breeding values for these traits, cows were classified as high, average, or low responders. The IRCM was calculated as the number of cases of mastitis experienced over the total time at risk throughout the 2-year study period. High-AMIR cows had an IRCM of 17.1 cases per 100 cow-years, which was significantly lower than average and low responders, with 27.9 and 30.7 cases per 100 cow-years, respectively. Low-AMIR cows tended to have the most severe mastitis. No differences in the IRCM were noted when cows were classified based on CMIR, likely due to the extracellular nature of mastitis-causing pathogens. The results of this study demonstrate the desirability of breeding dairy cattle for enhanced immune responses to decrease the incidence and severity of mastitis in the Canadian dairy industry. PMID:23175290

  5. New generation of high average power industry grade ultrafast ytterbium fiber lasers

    Science.gov (United States)

    Yusim, Alex; Samartsev, Igor; Shkurikhin, Oleg; Myasnikov, Daniil; Bordenyuk, Andrey; Platonov, Nikolai; Kancharla, Vijay; Gapontsev, Valentin

    2016-03-01

    We report an industrial grade picosecond and femtosecond pulse Yb fiber lasers with >100 μJ pulse energy and hundreds of Watts of average power for improved laser machining speed of sapphire and glass. This highly efficient laser offers >25% wall plug efficiency within a compact 3U rack-mountable configuration plus a long >2m fiber delivery cable. Reconfigurable features such as controllable repetition rate, fine pulse duration control, burst mode operation and adjustable pulse energy permit the customer to tailor the laser to their application.

  6. Dual-scale turbulence in filamenting laser beams at high average power

    CERN Document Server

    Schubert, Elise; Mongin, Denis; Kasparian, Jérôme; Wolf, Jean-Pierre; Klingebiel, Sandro; Schultze, Marcel; Metzger, Thomas; Michel, Knut

    2016-01-01

    We investigate the self-induced turbulence of high repetition rate laser filaments over a wide range of average powers (1 mW to 100 W) and its sensitivity to external atmospheric turbulence. Although both externally-imposed and self-generated turbulences can have comparable magnitudes, they act on different temporal and spatial scales. While the former drives the shot-to-shot motion at the millisecond time scale, the latter acts on the 0.5 s scale. As a consequence, their effects are decoupled, preventing beam stabilization by the thermally-induced low-density channel produced by the laser filaments.

  7. Development and significance of a fetal electrocardiogram recorded by signal-averaged high-amplification electrocardiography.

    Science.gov (United States)

    Hayashi, Risa; Nakai, Kenji; Fukushima, Akimune; Itoh, Manabu; Sugiyama, Toru

    2009-03-01

    Although ultrasonic diagnostic imaging and fetal heart monitors have undergone great technological improvements, the development and use of fetal electrocardiograms to evaluate fetal arrhythmias and autonomic nervous activity have not been fully established. We verified the clinical significance of the novel signal-averaged vector-projected high amplification ECG (SAVP-ECG) method in fetuses from 48 gravidas at 32-41 weeks of gestation and in 34 neonates. SAVP-ECGs from fetuses and newborns were recorded using a modified XYZ-leads system. Once noise and maternal QRS waves were removed, the P, QRS, and T wave intervals were measured from the signal-averaged fetal ECGs. We also compared fetal and neonatal heart rates (HRs), coefficients of variation of heart rate variability (CV) as a parasympathetic nervous activity, and the ratio of low to high frequency (LF/HF ratio) as a sympathetic nervous activity. The rate of detection of a fetal ECG by SAVP-ECG was 72.9%, and the fetal and neonatal QRS and QTc intervals were not significantly different. The neonatal CVs and LF/HF ratios were significantly increased compared with those in the fetus. In conclusion, we have developed a fetal ECG recording method using the SAVP-ECG system, which we used to evaluate autonomic nervous system development.

  8. Status of HiLASE project: High average power pulsed DPSSL systems for research and industry

    Directory of Open Access Journals (Sweden)

    Mocek T.

    2013-11-01

    Full Text Available We introduce the Czech national R&D project HiLASE which focuses on strategic development of advanced high-repetition rate, diode pumped solid state laser (DPSSL systems that may find use in research, high-tech industry and in the future European large-scale facilities such as HiPER and ELI. Within HiLASE we explore two major concepts: thin-disk and cryogenically cooled multislab amplifiers capable of delivering average output powers above 1 kW level in picosecond-to-nanosecond pulsed regime. In particular, we have started a programme of technology development to demonstrate the scalability of multislab concept up to the kJ level at repetition rate of 1–10 Hz.

  9. Status of HiLASE project: High average power pulsed DPSSL systems for research and industry

    Science.gov (United States)

    Mocek, T.; Divoky, M.; Smrz, M.; Sawicka, M.; Chyla, M.; Sikocinski, P.; Vohnikova, H.; Severova, P.; Lucianetti, A.; Novak, J.; Rus, B.

    2013-11-01

    We introduce the Czech national R&D project HiLASE which focuses on strategic development of advanced high-repetition rate, diode pumped solid state laser (DPSSL) systems that may find use in research, high-tech industry and in the future European large-scale facilities such as HiPER and ELI. Within HiLASE we explore two major concepts: thin-disk and cryogenically cooled multislab amplifiers capable of delivering average output powers above 1 kW level in picosecond-to-nanosecond pulsed regime. In particular, we have started a programme of technology development to demonstrate the scalability of multislab concept up to the kJ level at repetition rate of 1-10 Hz.

  10. High average power CO II laser MOPA system for Tin target LPP EUV light source

    Science.gov (United States)

    Ariga, Tatsuya; Hoshino, Hideo; Endo, Akira

    2007-02-01

    Extreme ultraviolet lithography (EUVL) is the candidate for next generation lithography to be introduced by the semiconductor industry to HVM (high volume manufacturing) in 2013. The power of the EUVL light source has to be at least 115W at a wavelength of 13.5nm. A laser produced plasma (LPP) is the main candidate for this light source but a cost effective laser driver is the key requirement for the realization of this concept. We are currently developing a high power and high repetition rate CO II laser system to achieve 50 W intermediate focus EUV power with a Tin droplet target. We have achieved CE of 2.8% with solid Tin wire target by a transversely excited atmospheric (TEA) CO II laser MOPA system with pulse width, pulse energy and pulse repetition rate as 10~15 ns, 30 mJ and 10 Hz, respectively. A CO II laser system with a short pulse length less than 15 ns, a nominal average power of a few kW, and a repetition rate of 100 kHz, based on RF-excited, fast axial flow CO II laser amplifiers is under development. Output power of about 3 kW has been achieved with a pulse length of 15 ns at 130 kHz repletion rate in a small signal amplification condition with P(20) single line. The phase distortion of the laser beam after amplification is negligible and the beam can be focused to about 150μm diameter in 1/e2. The CO II laser system is reported on short pulse amplification performance using RF-excited fast axial flow lasers as amplifiers. And the CO II laser average output power scaling is shown towards 5~10 kW with pulse width of 15 ns from a MOPA system.

  11. Average Anisotropy Characteristics of High Energy Cosmic Ray Particles and Geomagnetic Disturbance Index Ap

    Indian Academy of Sciences (India)

    C. M. Tiwari; D. P. Tiwari; Ajay K. Pandey; Pankaj K. Shrivastava

    2005-12-01

    The average characteristics of the diurnal and semi-diurnal anisotropy of cosmic ray intensity at relativistic energies have been obtained by using data from the worldwide grid of neutron monitor for the period 1989 to 1996. The complex behaviour of the diurnal amplitudes and time of maxima (phase) and its association with the Ap index on a long-term and day-to-day basis have been studied. Even though the general characteristics, on a yearly average basis, have not changed significantly during this period, both the diurnal and semi-diurnal amplitudes and phases vary significantly, besides significant changes being observed for different interplanetary conditions on a short-term basis. It is found that the relationship between the Ap index and the diurnal vector is out of phase during the period 1991 to 1995. On a long-term basis, the correlation of diurnal variation with Ap index has been found to vary during the solar cycle. On a short-term basis, it has been observed that the high Ap days are usually associated with higher amplitudes with phase shifted to earlier hours.

  12. A high-sensitivity 2x2 multi-aperture color camera based on selective averaging

    Science.gov (United States)

    Zhang, Bo; Kagawa, Keiichiro; Takasawa, Taishi; Seo, Min-Woong; Yasutomi, Keita; Kawahito, Shoji

    2015-03-01

    To demonstrate the low-noise performance of the multi-aperture imaging system using a selective averaging method, an ultra-high-sensitivity multi-aperture color camera with 2×2 apertures is being developed. In low-light conditions, random telegraph signal (RTS) noise and dark current white defects become visible, which greatly degrades the quality of the image. To reduce these kinds of noise as well as to increase the number of incident photons, the multi-aperture imaging system composed of an array of lens and CMOS image sensor (CIS), and the selective averaging for minimizing the synthetic sensor noise at every pixel is utilized. It is verified by simulation that the effective noise at the peak of noise histogram is reduced from 1.44 e- to 0.73 e- in a 2×2-aperture system, where RTS noise and dark current white defects have been successfully removed. In this work, a prototype based on low-noise color sensors with 1280×1024 pixels fabricated in 0.18um CIS technology is considered. The pixel pitch is 7.1μm×7.1μm. The noise of the sensor is around 1e- based on the folding-integration and cyclic column ADCs, and the low voltage differential signaling (LVDS) is used to improve the noise immunity. The synthetic F-number of the prototype is 0.6.

  13. Optimisation of high average power optical parametric generation using a photonic crystal fiber.

    Science.gov (United States)

    Sloanes, Trefor; McEwan, Ken; Lowans, Brian; Michaille, Laurent

    2008-11-24

    In this paper the length of a photonic crystal fiber is optimised to perform high average output power parametric generation with maximum efficiency. It is shown that the fiber length has to be increased up to 150 m, well beyond the walk-off distance between the pump and signal/idler, to optimize the generation efficiency. In this regime, the Raman process can take over from four-wave mixing and lead to supercontinuum generation. It is shown that the parametric wavelength conversion is directional; probably due to small variations in the core dimensions along the fiber length. The fiber exhibits up to 40% conversion efficiency, with the idler (0.9 microm) and the signal (1.3 microm) having a combined output power of over 1.5 W.

  14. The Mercury Project: A High Average Power, Gas-Cooled Laser For Inertial Fusion Energy Development

    Energy Technology Data Exchange (ETDEWEB)

    Bayramian, A; Armstrong, P; Ault, E; Beach, R; Bibeau, C; Caird, J; Campbell, R; Chai, B; Dawson, J; Ebbers, C; Erlandson, A; Fei, Y; Freitas, B; Kent, R; Liao, Z; Ladran, T; Menapace, J; Molander, B; Payne, S; Peterson, N; Randles, M; Schaffers, K; Sutton, S; Tassano, J; Telford, S; Utterback, E

    2006-11-03

    Hundred-joule, kilowatt-class lasers based on diode-pumped solid-state technologies, are being developed worldwide for laser-plasma interactions and as prototypes for fusion energy drivers. The goal of the Mercury Laser Project is to develop key technologies within an architectural framework that demonstrates basic building blocks for scaling to larger multi-kilojoule systems for inertial fusion energy (IFE) applications. Mercury has requirements that include: scalability to IFE beamlines, 10 Hz repetition rate, high efficiency, and 10{sup 9} shot reliability. The Mercury laser has operated continuously for several hours at 55 J and 10 Hz with fourteen 4 x 6 cm{sup 2} ytterbium doped strontium fluoroapatite (Yb:S-FAP) amplifier slabs pumped by eight 100 kW diode arrays. The 1047 nm fundamental wavelength was converted to 523 nm at 160 W average power with 73% conversion efficiency using yttrium calcium oxy-borate (YCOB).

  15. On the XFEL Schrödinger Equation: Highly Oscillatory Magnetic Potentials and Time Averaging

    KAUST Repository

    Antonelli, Paolo

    2014-01-14

    We analyse a nonlinear Schrödinger equation for the time-evolution of the wave function of an electron beam, interacting selfconsistently through a Hartree-Fock nonlinearity and through the repulsive Coulomb interaction of an atomic nucleus. The electrons are supposed to move under the action of a time dependent, rapidly periodically oscillating electromagnetic potential. This can be considered a simplified effective single particle model for an X-ray free electron laser. We prove the existence and uniqueness for the Cauchy problem and the convergence of wave-functions to corresponding solutions of a Schrödinger equation with a time-averaged Coulomb potential in the high frequency limit for the oscillations of the electromagnetic potential. © 2014 Springer-Verlag Berlin Heidelberg.

  16. Average Neutron Total Cross Sections in the Unresolved Energy Range From ORELA High Resolutio Transmission Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, H

    2004-05-27

    Average values of the neutron total cross sections of {sup 233}U, {sup 235}U, {sup 238}U, and {sup 239}Pu have been obtained in the unresolved resonance energy range from high-resolution transmission measurements performed at ORELA in the past two decades. The cross sections were generated by correcting the effective total cross sections for the self-shielding effects due to the resonance structure of the data. The self-shielding factors were found by calculating the effective and true cross sections with the computer code SAMMY for the same Doppler and resolution conditions as for the transmission measurements, using an appropriate set of resonance parameters. Our results are compared to results of previous measurements and to the current ENDF/B-VI data.

  17. Cryogenic nanosecond and picosecond high average and peak power(HAPP) pump lasers for ultrafast applications

    Institute of Scientific and Technical Information of China (English)

    David C.Brown; Sten Tornegrd; Joseph Kolis

    2016-01-01

    Using cryogenic laser technology, it is now possible to design and demonstrate lasers that have concomitant high average and peak powers, with near-diffraction-limited beam quality. We refer to these new laser systems as HAPP lasers. In this paper, we review important laser crystal materials properties at cryogenic temperature, with an emphasis on Yb lasers, and discuss the important design considerations, including the laser-induced damage threshold, nonlinear effects and thermal effects. A comprehensive model is presented to describe diode pulsed pumping with arbitrary duration and repetition rate, and is used with the Frantz–Nodvik equation to describe, to first order, the performance of HAPP laser systems. A computer code with representative results is also described.

  18. Comparative Study of Reynolds Averaged and Embedded Large Eddy Simulations of a High Pressure Turbine Stage

    Science.gov (United States)

    Jones, Sam; Jemcov, Aleksandar; Corke, Thomas

    2016-11-01

    An Embedded Large Eddy Simulation (ELES) approach is used to simulate the flow path through a high pressure turbine stage that includes the entry duct, stationary inlet and exit guide vanes, and a rotor. The flowfield around the rotor is simulated using LES. A Reynolds Averaged Simulation (RAS) is used for the rest of the flow domain. The interface between RAS and LES domains uses the RAS turbulence quantities as a means of obtaining length scales that are used in computing the vorticity required to trigger a proper energy cascade within the LES part of the flow field. The objective is to resolve the unsteady vortical motions that eminate from the gap between the rotor tip and duct walls that are presumably under-resolved in a RAS approach. A comparative analysis between RAS and ELES approaches for this turbomachinery problem is then presented. APS Fellow.

  19. High average power Q-switched 1314 nm two-crystal Nd:YLF laser

    CSIR Research Space (South Africa)

    Botha, RC

    2015-02-01

    Full Text Available . 40, No. 4 / OPTICS LETTERS High average power Q-switched 1314 nm two-crystal Nd:YLF laser R. C. Botha,1,2,* W. Koen,3 M. J. D. Esser,3,4 C. Bollig,3,5 W. L. Combrinck,1,6 H. M. von Bergmann,2 and H. J. Strauss3 1HartRAO, P.O. Box 443..., Krugersdorp, 1740 South Africa 2Stellenbosch University, P/Bag X1, Matieland, 7602 South Africa 3National Laser Centre, CSIR, PO Box 395, Pretoria, 0001 South Africa 4Formerly at CSIR, now at Heriot-Watt University, EH14 4AS Edinburgh, UK 5Formerly at CSIR...

  20. Selling students short: Racial differences in teachers' evaluations of high, average, and low performing students.

    Science.gov (United States)

    Irizarry, Yasmiyn

    2015-07-01

    Education scholars document notable racial differences in teachers' perceptions of students' academic skills. Using data from the Early Childhood Longitudinal Study-Kindergarten Cohort, this study advances research on teacher perceptions by investigating whether racial differences in teachers' evaluations of first grade students' overall literacy skills vary for high, average, and low performing students. Results highlight both the overall accuracy of teachers' perceptions, and the extent and nature of possible inaccuracies, as demonstrated by remaining racial gaps net literacy test performance. Racial differences in teachers' perceptions of Black, non-White Latino, and Asian students (compared to White students) exist net teacher and school characteristics and vary considerably across literacy skill levels. Skill specific literacy assessments appear to explain the remaining racial gap for Asian students, but not for Black and non-White Latino students. Implications of these findings for education scholarship, gifted education, and the achievement gap are discussed.

  1. Efficient Pumping Schemes for High Average Brightness Collisional X-ray Lasers

    Energy Technology Data Exchange (ETDEWEB)

    Keenan, R; Dunn, J; Shlyaptsev, V N; Smith, R F; Patel, P K; Price, D F

    2003-10-07

    Advances in transient collisional x-ray lasers have been demonstrated over the last 5 years as a technique for achieving tabletop soft x-ray lasers using 2-10 J of laser pump energy. The high peak brightness of these sources operating in the high output saturation regime, in the range of 10{sup 24}-10{sup 25} ph. mm{sup -2} mrad{sup -2} s-1 (0.1% BW){sup -1}, is ideal for many applications requiring high photon fluence in a single short burst. However, the pump energy required for these x-ray lasers is still relatively high and limits the x-ray laser repetition rate to 1 shot every few minutes. Higher repetition rate collisional schemes have been reported and show some promise for high output in the future. We report a novel technique for enhancing the coupling efficiency of the laser pump into the gain medium that could lead to enhanced x-ray inversion with a factor of ten reduction in the drive energy. This has been applied to the collisional excitation scheme for Ni-like Mo at 18.9 nm and x-ray laser output has been demonstrated. Preliminary results show lasing on a single shot of the optical laser operating at 10 Hz and with 70 mJ in the short pulse. Such a proposed source would have higher average brightness, {approx}10{sup 14} ph. mm{sup -2} mrad{sup -2} s{sup -1} (0.1% BW){sup -1}, than present bending magnet 3rd generation synchrotron sources operating at the same spectral range.

  2. Intraindividual neuropsychological test variability in healthy individuals with high average intelligence and educational attainment.

    Science.gov (United States)

    Heyanka, Daniel J; Holster, Jessica L; Golden, Charles J

    2013-08-01

    Knowledge of patterns of neuropsychological performance among normal, healthy individuals is integral to the practice of clinical neuropsychology, because clinicians may not always account for intraindividual variability (IIV) before coming to diagnostic conclusions. The IIV was assessed among a sample of 46 healthy individuals with high average intelligence and educational attainment, utilizing a battery of neuropsychological tests, including the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) and Wechsler Memory Scale, Fourth Edition (WMS-IV). The data indicated substantial variability in neurocognitive abilities. All participants were found to demonstrate scores considered impaired by at least 2 standard deviations (SDs). Despite adjusting for outliers, no participant produced a "normal" testing profile with an intraindividual maximum discrepancy (MD) of less than 1 SD in either direction. When WAIS-IV Full Scale IQ (FSIQ) was considered, participants generally demonstrated cognitive test scores ranging from 2 SDs less than to 1.5 SDs greater than their FSIQ. Furthermore, after demographic corrections, the majority (59%) of participants demonstrated at least 1 impaired cognitive test score, as defined by being 1 to 1.5 SDs below the mean. Overall, results substantiate the need for clinicians to consider FSIQ and educational attainment in interpretation of neuropsychological testing results, given the relevant commonality of "abnormal" test scores within this population. This may ultimately reduce the likelihood of making false-positive conclusions of impairment when educational attainment and intelligence are high, thus improving diagnostic accuracy.

  3. Hard Water or High Ages?

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2008-01-01

    The aim of this thesis is the investigation of the hardwater effect and its implications for the dating of the first occurrence of pottery in Northern Germany. The hardwater effect denotes the effect of a high carbonate content of freshwater on radiocarbon dating: the dissolved minerals can lead...

  4. The influence of averageness on judgments of facial attractiveness: no own-age or own-sex advantage among children attending single-sex schools.

    Science.gov (United States)

    Vingilis-Jaremko, Larissa; Maurer, Daphne; Gao, Xiaoqing

    2014-04-01

    We examined how recent biased face experience affects the influence of averageness on judgments of facial attractiveness among 8- and 9-year-old children attending a girls' school, a boys' school, and a mixed-sex school. We presented pairs of individual faces in which one face was transformed 50% toward its group average, whereas the other face was transformed 50% away from that average. Across blocks, the faces varied in age (adult, 9-year-old, or 5-year-old) and sex (male or female). We expected that averageness might influence attractiveness judgments more strongly for same-age faces and, for children attending single-sex schools, same-sex faces of that age because their prototype(s) should be best tuned to the faces they see most frequently. Averageness influenced children's judgments of attractiveness, but the strength of the influence was not modulated by the age of the face, nor did the effects of sex of face differ across schools. Recent biased experience might not have affected the results because of similarities between the average faces of different ages and sexes and/or because a minimum level of experience with a particular group of faces may be adequate for the formation of a veridical prototype and its influence on judgments of attractiveness. The results suggest that averageness affects children's judgments of the attractiveness of the faces they encounter in everyday life regardless of age or sex of face. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. A Comparison of Strategic Development for Multiplication Problem Solving in Low-, Average-, and High-Achieving Students

    Science.gov (United States)

    Zhang, Dake; Ding, Yi; Barrett, Dave E.; Xin, Yan Ping; Liu, Ru-de

    2014-01-01

    The present study investigated the differences of strategy use between low-, average-, and high-achieving students when solving different multiplication problems. Nineteen high-, 48 average-, and 17 low-achieving students participated in this study. All participants were asked to complete three different multiplication tests and to explain how…

  6. Average age at death in infancy and infant mortality level: Reconsidering the Coale-Demeny formulas at current levels of low mortality

    Directory of Open Access Journals (Sweden)

    Evgeny M. Andreev

    2015-08-01

    Full Text Available Background: The long-term historical decline in infant mortality has been accompanied by increasing concentration of infant deaths at the earliest stages of infancy. In the mid-1960s Coale and Demeny developed formulas describing the dependency of the average age of death in infancy on the level of infant mortality, based on data obtained up to that time. Objective: In the more developed countries a steady rise in average age of infant death began in the mid-1960s. This paper documents this phenomenon and offers alternative formulas for calculation of the average age of death, taking into account the new mortality trends. Methods: Standard statistical methodologies and a specially developed method are applied to the linked individual birth and infant death datasets available from the US National Center for Health Statistics and the initial (raw numbers of deaths from the Human Mortality Database. Results: It is demonstrated that the trend of decline in the average age of infant death becomes interrupted when the infant mortality rate attains a level around 10 per 1000, and modifications of the Coale-Demeny formulas for practical application to contemporary low levels of mortality are offered. Conclusions: The average age of death in infancy is an important characteristic of infant mortality, although it does not influence the magnitude of life expectancy. That the increase in average age of death in infancy is connected with medical advances is proposed as a possible explanation.

  7. Somatic component of risk of the development of vegetative-vascular dysfunction at children of the average and advanced school age

    Directory of Open Access Journals (Sweden)

    Olena Savchuk

    2016-10-01

    Full Text Available Purpose: to estimate quantitatively factors of somatic component of risk of the development of vegetative-vascular dysfunction at children of the average and advanced school age. Material & Methods: 569 children of 14–17 years old are examined in order to the existence of somatopathies, violation of posture, level and harmony of physical development, extent of development of adipopexis, functional indicators of health. Influence of somatic factors on risk of developing of vegetative-vascular dysfunction was revealed by means of the correlation analysis. Results: the system of assessment and the integrated indicator of action of somatic factors on risk of the development of vegetative-vascular dysfunction are offered. 6,57% of pupils with the low level of probability of risk of developing of vegetative-vascular dysfunction, 24,25% of pupils with the level below the average, 38,36% of children of 14–17 years old with the average level of probability of risk of developing of vegetative-vascular dysfunction, 24,25% of teenagers with the average level of probability, 6,57% of pupils with the high level of probability of risk of developing of vegetative-vascular dysfunction are revealed. The reliable communications between the low level of functionality on the test of Ruffier and the disharmonious physical development (p<0,001, low indicators of power and respiratory indexes (p<0,05 are established statistically. Conclusions: the children of the group of risk, who need the individual approach at lessons of physical culture, are defined.

  8. Information Entropy- and Average-Based High-Resolution Digital Storage Oscilloscope

    Directory of Open Access Journals (Sweden)

    Jun Jiang

    2014-01-01

    Full Text Available Vertical resolution is an essential indicator of digital storage oscilloscope (DSO and the key to improving resolution is to increase digitalizing bits and lower noise. Averaging is a typical method to improve signal to noise ratio (SNR and the effective number of bits (ENOB. The existing averaging algorithm is apt to be restricted by the repetitiveness of signal and be influenced by gross error in quantization, and therefore its effect on restricting noise and improving resolution is limited. An information entropy-based data fusion and average-based decimation filtering algorithm, proceeding from improving average algorithm and in combination with relevant theories of information entropy, are proposed in this paper to improve the resolution of oscilloscope. For single acquiring signal, resolution is improved through eliminating gross error in quantization by utilizing the maximum entropy of sample data with further noise filtering via average-based decimation after data fusion of efficient sample data under the premise of oversampling. No subjective assumptions and constraints are added to the signal under test in the whole process without any impact on the analog bandwidth of oscilloscope under actual sampling rate.

  9. Average gene length is highly conserved in prokaryotes and eukaryotes and diverges only between the two kingdoms.

    Science.gov (United States)

    Xu, Lin; Chen, Hong; Hu, Xiaohua; Zhang, Rongmei; Zhang, Ze; Luo, Z W

    2006-06-01

    The average length of genes in a eukaryote is larger than in a prokaryote, implying that evolution of complexity is related to change of gene lengths. Here, we show that although the average lengths of genes in prokaryotes and eukaryotes are much different, the average lengths of genes are highly conserved within either of the two kingdoms. This suggests that natural selection has clearly set a strong limitation on gene elongation within the kingdom. Furthermore, the average gene size adds another distinct characteristic for the discrimination between the two kingdoms of organisms.

  10. Numerical Investigation of Thermal Effect in Plasma Electrode Pockels Cell for High Average Power

    Institute of Scientific and Technical Information of China (English)

    CAO Ding-Xiang; ZHANG Xiong-Jun; ZHENG Wan-Guo; HE Shao-Bo; SUI Zhan

    2006-01-01

    @@ The average power of a Pockels cell is limited by thermal effects arising from the optical absorption of the laser pulse. These thermal effects can be managed by configuring the switch as a plasma-electrode thin plate Pockels cell, which works under heat-capacity operation. Simulation results show that, based on KD*P (in thickness 0.5cm) at an average power loading of 1 kW, the aperture integrated depolarization loss at 1.06 um is less than 10% in 5min working time.

  11. Enhanced flat adenoma detection rate with high definition colonoscopy plus i-scan for average-risk colorectal cancer screening

    Directory of Open Access Journals (Sweden)

    Antonio Rodríguez-D'Jesús

    Full Text Available Background and aim: The usefulness of high definition colonoscopy plus i-scan (HD+i-SCAN for average-risk colorectal cancer screening has not been fully assessed. The detection rate of adenomas and other measurements such as the number of adenomas per colonoscopy and the flat adenoma detection rate have been recognized as markers of colonoscopy quality. The aim of the present study was to compare the diagnostic performance of an HD+i-SCAN with that of standard resolution white-light colonoscope. Methods: This is a retrospective analysis of a prospectively collected screening colonoscopy database. A comparative analysis of the diagnostic yield of an HD+i-SCAN or standard resolution colonoscopy for average-risk colorectal screening was conducted. Results: During the period of study, 155/163 (95.1% patients met the inclusion criteria. The mean age was 56.9 years. Sixty of 155 (39% colonoscopies were performed using a HD+i-SCAN. Adenoma-detection-rates during the withdrawal of the standard resolution versus HD+i-SCAN colonoscopies were 29.5% and 30% (p = n.s.. Adenoma/colonoscopy values for standard resolution versus HD+i-SCAN colonoscopies were 0.46 (SD = 0.9 and 0.72 (SD = 1.3 (p = n.s.. A greater number of flat adenomas were detected in the HD+i-SCAN group (6/60 vs. 2/95 (p < .05. Likewise, serrated adenomas/polyps per colonoscopy were also higher in the HD+i-SCAN group. Conclusions: A HD+i-SCAN colonoscopy increases the flat adenoma detection rate and serrated adenomas/polyps per colonoscopy compared to a standard colonoscopy in average-risk screening population. HD+i-SCAN is a simple, available procedure that can be helpful, even for experienced providers. The performance of HD+i-SCAN and substantial prevalence of flat lesions in our average-risk screening cohort support its usefulness in improving the efficacy of screening colonoscopies.

  12. Generation and applications of high average power Mid-IR supercontinuum in chalcogenide fibres

    DEFF Research Database (Denmark)

    Petersen, Christian Rosenberg

    2016-01-01

    Mid-infrared supercontinuum with up to 54.8 mW average power, and maximum bandwidth of 1.77-8.66 μm is demonstrated as a result of pumping tapered chalcogenide photonic crystal fibers with a MHz parametric source at 4 μm....

  13. Charge and fluence lifetime measurements of a dc high voltage GaAs photogun at high average current

    Energy Technology Data Exchange (ETDEWEB)

    J. Grames, R. Suleiman, P.A. Adderley, J. Clark, J. Hansknecht, D. Machie, M. Poelker, M.L. Stutzman

    2011-04-01

    GaAs-based dc high voltage photoguns used at accelerators with extensive user programs must exhibit long photocathode operating lifetime. Achieving this goal represents a significant challenge for proposed high average current facilities that must operate at tens of milliamperes or more. This paper describes techniques to maintain good vacuum while delivering beam, and techniques that minimize the ill effects of ion bombardment, the dominant mechanism that reduces photocathode yield of a GaAs-based dc high voltage photogun. Experimental results presented here demonstrate enhanced lifetime at high beam currents by: (a) operating with the drive laser beam positioned away from the electrostatic center of the photocathode, (b) limiting the photocathode active area to eliminate photoemission from regions of the photocathode that do not support efficient beam delivery, (c) using a large drive laser beam to distribute ion damage over a larger area, and (d) by applying a relatively low bias voltage to the anode to repel ions created within the downstream beam line. A combination of these techniques provided the best total charge extracted lifetimes in excess of 1000 C at dc beam currents up to 9.5 mA, using green light illumination of bulk GaAs inside a 100 kV photogun.

  14. State Averages

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of a variety of averages for each state or territory as well as the national average, including each quality measure, staffing, fine amount and number of...

  15. Thermal distortion and birefringence in repetition-rate plasma electrode Pockels cell for high average power

    Institute of Scientific and Technical Information of China (English)

    Dingxiang Cao; Xiongjun Zhang; Wanguo Zheng; Shaobo He; Zhan Sui

    2007-01-01

    We numerically study thermally induced birefringence and distortion in plasma electrode Pockels cell based on KD*P as the electro-optic material. This device can repetitively operate under the heat capacity mode.Simulation results indicate that the excellent switching performances and low wave-front distortion are achieved within several tens seconds working time at average power in excess of 1 kW.

  16. A comment on the average foil-hit number for a high-intensity proton ring

    CERN Document Server

    Yamane, I

    2002-01-01

    The minimum value of the average foil-hit number is derived for H sup - charge-exchange injection using a stripping foil, in which the H sup - beam is injected at a corner of the stripper foil and the cross-sectional area of the ring beam is increased as a function of time, kt sup 1 sup / sup n , where k and n are constants.

  17. Multi-session complex averaging for high resolution high SNR 3T MR visualization of ex vivo hippocampus and insula

    Science.gov (United States)

    Stamm, Aymeric; Singh, Jolene M.; Scherrer, Benoit; Afacan, Onur; Warfield, Simon K.

    2015-03-01

    The hippocampus and the insula are responsible for episodic memory formation and retrieval. Hence, visualization of the cytoarchitecture of such structures is of primary importance to understand the underpinnings of conscious experience. Magnetic Resonance Imaging (MRI) offers an opportunity to non-invasively image these crucial structures. However, current clinical MR imaging operates at the millimeter scale while these anatomical landmarks are organized into sub-millimeter structures. For instance, the hippocampus contains several layers, including the CA3-dentate network responsible for encoding events and experiences. To investigate whether memory loss is a result of injury or degradation of CA3/dentate, spatial resolution must exceed one hundred micron, isotropic, voxel size. Going from one millimeter voxels to one hundred micron voxels results in a 1000× signal loss, making the measured signal close to or even way below the precision of the receiving coils. Consequently, the signal magnitude that forms the structural images will be biased and noisy, which results in inaccurate contrast and less than optimal signal-to-noise ratio (SNR). In this paper, we propose a strategy to perform high spatial resolution MR imaging of the hippocampus and insula with 3T scanners that enables accurate contrast (no systematic bias) and arbitrarily high SNR. This requires the collection of additional repeated measurements of the same image and a proper averaging of the k-space data in the complex domain. This comes at the cost of additional scan time, but long single-session scan times are not practical for obvious reasons. Hence, we also develop an approach to combine k-space data from multiple sessions, which enables the total scan time to be split into arbitrarily short sessions, where the patient is allowed to move and rest in-between. For validation, we hereby illustrate our multi-session complex averaging strategy by providing high spatial resolution 3T MR visualization

  18. Femtosecond and picosecond laser drilling of metals at high repetition rates and average powers.

    Science.gov (United States)

    Ancona, A; Döring, S; Jauregui, C; Röser, F; Limpert, J; Nolte, S; Tünnermann, A

    2009-11-01

    The influence of pulse duration on the laser drilling of metals at repetition rates of up to 1 MHz and average powers of up to 70 W has been experimentally investigated using an ytterbium-doped-fiber chirped-pulse amplification system with pulses from 800 fs to 19 ps. At a few hundred kilohertz particle shielding causes an increase in the number of pulses for breakthrough, depending on the pulse energy and duration. At higher repetition rates, the heat accumulation effect overbalances particle shielding, but significant melt ejection affects the hole quality. Using femtosecond pulses, heat accumulation starts at higher repetition rates, and the ablation efficiency is higher compared with picosecond pulses.

  19. Multi-Repeated Projection Lithography for High-Precision Linear Scale Based on Average Homogenization Effect

    Directory of Open Access Journals (Sweden)

    Dongxu Ren

    2016-04-01

    Full Text Available A multi-repeated photolithography method for manufacturing an incremental linear scale using projection lithography is presented. The method is based on the average homogenization effect that periodically superposes the light intensity of different locations of pitches in the mask to make a consistent energy distribution at a specific wavelength, from which the accuracy of a linear scale can be improved precisely using the average pitch with different step distances. The method’s theoretical error is within 0.01 µm for a periodic mask with a 2-µm sine-wave error. The intensity error models in the focal plane include the rectangular grating error on the mask, static positioning error, and lithography lens focal plane alignment error, which affect pitch uniformity less than in the common linear scale projection lithography splicing process. It was analyzed and confirmed that increasing the repeat exposure number of a single stripe could improve accuracy, as could adjusting the exposure spacing to achieve a set proportion of black and white stripes. According to the experimental results, the effectiveness of the multi-repeated photolithography method is confirmed to easily realize a pitch accuracy of 43 nm in any 10 locations of 1 m, and the whole length accuracy of the linear scale is less than 1 µm/m.

  20. Multi-Repeated Projection Lithography for High-Precision Linear Scale Based on Average Homogenization Effect.

    Science.gov (United States)

    Ren, Dongxu; Zhao, Huiying; Zhang, Chupeng; Yuan, Daocheng; Xi, Jianpu; Zhu, Xueliang; Ban, Xinxing; Dong, Longchao; Gu, Yawen; Jiang, Chunye

    2016-04-14

    A multi-repeated photolithography method for manufacturing an incremental linear scale using projection lithography is presented. The method is based on the average homogenization effect that periodically superposes the light intensity of different locations of pitches in the mask to make a consistent energy distribution at a specific wavelength, from which the accuracy of a linear scale can be improved precisely using the average pitch with different step distances. The method's theoretical error is within 0.01 µm for a periodic mask with a 2-µm sine-wave error. The intensity error models in the focal plane include the rectangular grating error on the mask, static positioning error, and lithography lens focal plane alignment error, which affect pitch uniformity less than in the common linear scale projection lithography splicing process. It was analyzed and confirmed that increasing the repeat exposure number of a single stripe could improve accuracy, as could adjusting the exposure spacing to achieve a set proportion of black and white stripes. According to the experimental results, the effectiveness of the multi-repeated photolithography method is confirmed to easily realize a pitch accuracy of 43 nm in any 10 locations of 1 m, and the whole length accuracy of the linear scale is less than 1 µm/m.

  1. Highly efficient sparse-matrix inversion techniques and average procedures applied to collisional-radiative codes

    CERN Document Server

    Poirier, M

    2009-01-01

    The behavior of non-local thermal-equilibrium (NLTE) plasmas plays a central role in many fields of modern-day physics, such as laser-produced plasmas, astrophysics, inertial or magnetic confinement fusion devices, or X-ray sources. The proper description of these media in stationary cases requires to solve linear systems of thousands or more rate equations. A possible simplification for this arduous numerical task may lie in some type of statistical average, such as configuration or superconfiguration average. However to assess the validity of this procedure and to handle cases where isolated lines play an important role, it may be important to deal with detailed levels systems. This involves matrices with sometimes billions of elements, which are rather sparse but still involve thousands of diagonals. We propose here a numerical algorithm based on the LU decomposition for such linear systems. This method turns out to be orders of magnitude faster than the traditional Gauss elimination. And at variance with ...

  2. High-average-power high-beam-quality vis-UV sources based on kinetically enhanced copper vapor lasers

    Science.gov (United States)

    Brown, Daniel J. W.; Withford, Michael J.; Carman, Robert J.; Mildren, Richard P.; Piper, James A.

    2000-04-01

    Investigations of the factors that limit average power scaling of elemental copper vapor lasers (CVLs) have demonstrated that decay of the electron density in the interpulse period is critical in restricting pulse repetition rate and laser aperture scaling. We have recently developed the 'kinetic enhancement' (or KE) technique to overcome these limitations, whereby optimal plasma conditions are engineered using low concentrations of HCl/H2 additive gases in the Ne buffer. Dissociative electron attachment of HCl and subsequent mutual neutralization of Cl- and Cu+ promote rapid plasma relaxation and fast recovery of Cu densities, permitting operation at elevated Cu densities and pulse rates for given apertures. Using this approach, we have demonstrated increases in output power and efficiency of a factor of 2 or higher over conventional CVLs of the same size. For a 38 mm- bore KE-CVL, output powers up to 150 W have been achieved at 22 kHz, corresponding to record specific powers (80 mW/cm3) for such a 'small/medium-scale' device. In addition, kinetic enhancement significantly extends the gain duration and restores gain on-axis, even for high pulse rates, thereby promoting substantial increases (5 - 10x) in high- beam-quality power levels when operating with unstable resonators. This has enabled us to achieve much higher powers in second-harmonic generation from the visible copper laser output to the ultraviolet (e.g. 5 W at 255 nm from a small- scale KE-CVL). Our approach to developing KE-CVLs including computer modeling and experimental studies will be reviewed, and most recent results in pulse rate scaling and scaling of high-beam-quality power using oscillator-amplifier configurations, will be presented.

  3. Age Trajectory of High Cognitive Functioning Among the Oldest Old

    DEFF Research Database (Denmark)

    Thinggaard, Mikael; McGue, Matt; Christensen, Kaare

    2013-01-01

    individual differences. This decline of cognitive functioning at an individual level may suggest that cognitive function at a population level decreases with age. However, in the Danish 1905 cohort, the age trajectory of both average and high cognitive functioning is constant at a population level from......The chance of reaching age 90 years has increased markedly over the last 50 years, and this chance will probably continue to increase with successive cohorts. There is a widespread concern that a large fraction of the future oldest old will be cognitively impaired. However, there is strong evidence...... that later born cohorts may have better late-life cognitive function than earlier born cohorts as studies have shown a decline both in the prevalence and in the incidence of dementia. Cognitive functioning generally declines after the age of 40 years at an individual level, but there are substantial...

  4. NEO-LISP: Deflecting near-Earth objects using high average power, repetitively pulsed lasers

    Science.gov (United States)

    Phipps, C. R.; Michaelis, M. M.

    Several kinds of Near-Earth objects exist for which one would like to cause modest orbit perturbations, but which are inaccessible to normal means of interception because of their number, distance or the lack of early warning. For these objects, LISP (Laser Impulse Space Propulsion) is an appropriate technique for rapidly applying the required mechanical impulse from a ground-based station. In order of increasing laser energy required, examples are: (1) repositioning specially prepared geosynchronous satellites for an enhanced lifetime; (2) causing selected items of space junk to re-enter and burn up in the atmosphere on a computed trajectory; and (3) safely deflecting Earth-directed comet nuclei and earth-crossing asteroids (ECA's) a few tens of meters in size (the most hazardous size). They will discuss each of these problems in turn and show that each application is best matched by its own matrix of LISP laser pulse width, pulse repetition rate, wavelength and average power. The latter ranges from 100W to 3GW for the cases considered. They will also discuss means of achieving the active beam phase error correction during passage through the atmosphere and very large exit pupil in the optical system which are required in each of these cases.

  5. Microbial Carbon Substrate Utilization Differences among High- and Average-Yield Soybean Areas

    National Research Council Canada - National Science Library

    Taylor C. Adams; Kristofor R. Brye; Mary C. Savin; Jung Ae Lee; Edward E. Gbur

    2017-01-01

    Since soybean (Glycine max L. (Merr.)) yields greater than 6719 kg ha−1 have only recently and infrequently been achieved, little is known about the soil microbiological environment related to high-yield soybean production...

  6. Is it better to be average? High and low performance as predictors of employee victimization.

    Science.gov (United States)

    Jensen, Jaclyn M; Patel, Pankaj C; Raver, Jana L

    2014-03-01

    Given increased interest in whether targets' behaviors at work are related to their victimization, we investigated employees' job performance level as a precipitating factor for being victimized by peers in one's work group. Drawing on rational choice theory and the victim precipitation model, we argue that perpetrators take into consideration the risks of aggressing against particular targets, such that high performers tend to experience covert forms of victimization from peers, whereas low performers tend to experience overt forms of victimization. We further contend that the motivation to punish performance deviants will be higher when performance differentials are salient, such that the effects of job performance on covert and overt victimization will be exacerbated by group performance polarization, yet mitigated when the target has high equity sensitivity (benevolence). Finally, we investigate whether victimization is associated with future performance impairments. Results from data collected at 3 time points from 576 individuals in 62 work groups largely support the proposed model. The findings suggest that job performance is a precipitating factor to covert victimization for high performers and overt victimization for low performers in the workplace with implications for subsequent performance.

  7. AVERAGE GEOMETRICAL FEATURES OF THE ELECTRON WAVE PACKAGES DISTRIBUTION IN METALLIC CONDUCTORS WITH PULSED AXIAL CURRENT OF HIGH DENSITY

    Directory of Open Access Journals (Sweden)

    M. I. Baranov

    2016-11-01

    Full Text Available Purpose. Calculation and experimental determination of average geometrical features of distributing of macroscopic electron wave packages (EWP in round cylindrical metallic conductors with the pulsed axial current of high density. Methodology. Theoretical bases of the electrical engineering, bases of atomic and quantum physics, electrophysics bases of technique of high voltage and high pulsed currents. Results. The results of the conducted calculation and experimental researches are resulted on close determination of average geometrical features of distribution of longitudinal and radial EWP of macroscopic sizes in the indicated conductors. These descriptions are included by the average widths of «hot» and «cold» longitudinal and radial areas of conductor, and also average steps of division into the periods of similar areas. Results of the executed calculations and high temperature experiments for average geometrical features of longitudinal EWP in the zincked steel wire of diameter of 1.6 mm and length of 320 mm with the aperiodic impulse of current of temporal form 9 ms/160 ms and by amplitude 745 A coincide within the limits of 19 %. Originality. First with the use of methods of atomic and quantum physics the features of the stochastic distributing and mean values of basic geometrical sizes are analysed macroscopic longitudinal and radial EWP in round cylindrical metallic conductors with the pulsed axial current of high density. Practical value. Drawing on the got results in practice will allow more reliably to forecast geometrical sizes and places of localization of arising up in the probed metallic conductors with pulsed axial current of high density longitudinal and radial EWP.

  8. Solid State Raman Materials Characterization for High Average Power 1.3 micrometer Laser Frequency Shift

    Science.gov (United States)

    1999-01-01

    reflectivity at 1067 rim wavelength. Solid state phototrop filter based on gallium -scandium- gadolinium garnet doped with chromium was used as a passive Q-switch... gadolinium tungstate, KGd(W0 4)2 exhibited efficient Raman properties . In spite of the fact that its Raman gain coefficient at 1064 nm (6 cm/GW) is twice less...studied by high- temperature Raman scattering (HTRS) technique. According to [1], the lattice cell of KGd(W04) 2 low - temperature modification is a base

  9. The Effect of Computer Based Instructional Technique for the Learning of Elementary Level Mathematics among High, Average and Low Achievers

    Science.gov (United States)

    Afzal, Muhammad Tanveer; Gondal, Bashir; Fatima, Nuzhat

    2014-01-01

    The major objective of the study was to elicit the effect of three instructional methods for teaching of mathematics on low, average and high achiever elementary school students. Three methods: traditional instructional method, computer assisted instruction (CAI) and teacher facilitated mathematics learning software were employed for the teaching…

  10. Are Confidence Ratings Test- or Trait-Driven? Individual Differences among High, Average, and Low Comprehenders in Fourth Grade

    Science.gov (United States)

    Kasperski, Ronen; Katzir, Tami

    2013-01-01

    The aim of this study was to examine whether low, average, and high comprehenders (LC, AC, and HC, respectively) differed in their reading self-confidence and bias ratings, and whether confidence ratings were driven by reading ability or distributed evenly among diverse readers. Seventy fourth-graders with good decoding abilities were administered…

  11. Are Confidence Ratings Test- or Trait-Driven? Individual Differences among High, Average, and Low Comprehenders in Fourth Grade

    Science.gov (United States)

    Kasperski, Ronen; Katzir, Tami

    2013-01-01

    The aim of this study was to examine whether low, average, and high comprehenders (LC, AC, and HC, respectively) differed in their reading self-confidence and bias ratings, and whether confidence ratings were driven by reading ability or distributed evenly among diverse readers. Seventy fourth-graders with good decoding abilities were administered…

  12. Design of a high average-power FEL driven by an existing 20 MV electrostatic-accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kimel, I.; Elias, L.R. [Univ. of Central Florida, Orlando, FL (United States)

    1995-12-31

    There are some important applications where high average-power radiation is required. Two examples are industrial machining and space power-beaming. Unfortunately, up to date no FEL has been able to show more than 10 Watts of average power. To remedy this situation we started a program geared towards the development of high average-power FELs. As a first step we are building in our CREOL laboratory, a compact FEL which will generate close to 1 kW in CW operation. As the next step we are also engaged in the design of a much higher average-power system based on a 20 MV electrostatic accelerator. This FEL will be capable of operating CW with a power output of 60 kW. The idea is to perform a high power demonstration using the existing 20 MV electrostatic accelerator at the Tandar facility in Buenos Aires. This machine has been dedicated to accelerate heavy ions for experiments and applications in nuclear and atomic physics. The necessary adaptations required to utilize the machine to accelerate electrons will be described. An important aspect of the design of the 20 MV system, is the electron beam optics through almost 30 meters of accelerating and decelerating tubes as well as the undulator. Of equal importance is a careful design of the long resonator with mirrors able to withstand high power loading with proper heat dissipation features.

  13. Sliding Mode Pulsed Averaging IC Drivers for High Brightness Light Emitting Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Anatoly Shteynberg, PhD

    2006-08-17

    This project developed new Light Emitting Diode (LED) driver ICs associated with specific (uniquely operated) switching power supplies that optimize performance for High Brightness LEDs (HB-LEDs). The drivers utilize a digital control core with a newly developed nonlinear, hysteretic/sliding mode controller with mixed-signal processing. The drivers are flexible enough to allow both traditional microprocessor interface as well as other options such as “on the fly” adjustment of color and brightness. Some other unique features of the newly developed drivers include • AC Power Factor Correction; • High power efficiency; • Substantially fewer external components should be required, leading to substantial reduction of Bill of Materials (BOM). Thus, the LED drivers developed in this research : optimize LED performance by increasing power efficiency and power factor. Perhaps more remarkably, the LED drivers provide this improved performance at substantially reduced costs compared to the present LED power electronic driver circuits. Since one of the barriers to market penetration for HB-LEDs (in particular “white” light LEDs) is cost/lumen, this research makes important contributions in helping the advancement of SSL consumer acceptance and usage.

  14. Method for optical pumping of thin laser media at high average power

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Luis E. (Livermore, CA); Beach, Raymond J. (Livermore, CA); Honea, Eric C. (Sunol, CA); Payne, Stephen A. (Castro Valley, CA)

    2004-07-13

    A thin, planar laser material is bonded to a light guide of an index-matched material forming a composite disk. Diode array or other pump light is introduced into the composite disk through the edges of the disk. Pump light trapped within the composite disk depletes as it multi-passes the laser medium before reaching an opposing edge of the disk. The resulting compound optical structure efficiently delivers concentrated pump light and to a laser medium of minimum thickness. The external face of the laser medium is used for cooling. A high performance cooler attached to the external face of the laser medium rejects heat. Laser beam extraction is parallel to the heat flux to minimize optical distortions.

  15. Overview of the HiLASE project: high average power pulsed DPSSL systems for research and industry

    Institute of Scientific and Technical Information of China (English)

    M.Divoky; M.Smrz; M.Chyla; P.Sikocinski; P.Severova; O.Novak; J.Huynh; S.S.Nagisetty; T.Miura; J.Pila; O.Slezak; M.Sawicka; V.Jambunathan; J.Vanda; A.Endo; A.Lucianetti; D.Rostohar; P.D.Mason; P.J.Phillips; K.Ertel; S.Banerjee; C.Hernandez-Gomez; J.L.Collier; T.Mocek

    2014-01-01

    An overview of the Czech national R&D project HiLASE(High average power pulsed laser) is presented. The project focuses on the development of advanced high repetition rate, diode pumped solid state laser(DPSSL) systems with energies in the range from mJ to 100 J and repetition rates in the range from 10 Hz to 100 kHz. Some applications of these lasers in research and hi-tech industry are also presented.

  16. The value of time-averaged serum high-sensitivity C-reactive protein in prediction of mortality and dropout in peritoneal dialysis patients.

    Science.gov (United States)

    Liu, Shou-Hsuan; Chen, Chao-Yu; Li, Yi-Jung; Wu, Hsin-Hsu; Lin, Chan-Yu; Chen, Yung-Chang; Chang, Ming-Yang; Hsu, Hsiang-Hao; Ku, Cheng-Lung; Tian, Ya-Chung

    2017-01-01

    C-reactive protein (CRP) is a useful biomarker for prediction of long-term outcomes in patients undergoing chronic dialysis. This observational cohort study evaluated whether the time-averaged serum high-sensitivity CRP (HS-CRP) level was a better predictor of clinical outcomes than a single HS-CRP level in patients undergoing peritoneal dialysis (PD). We classified 335 patients into three tertiles according to the time-averaged serum HS-CRP level and followed up regularly from January 2010 to December 2014. Clinical outcomes such as cardiovascular events, infection episodes, newly developed malignancy, encapsulating peritoneal sclerosis (EPS), dropout (death plus conversion to hemodialysis), and mortality were assessed. During a 5-year follow-up, 164 patients (49.0%) ceased PD; this included 52 patient deaths (15.5%), 100 patients (29.9%) who converted to hemodialysis, and 12 patients (3.6%) who received a kidney transplantation. The Kaplan-Meier survival analysis and log-rank test revealed a significantly worse survival accumulation in patients with high time-average HS-CRP levels. A multivariate Cox regression analysis revealed that a higher time-averaged serum HS-CRP level, older age, and the occurrence of cardiovascular events were independent mortality predictors. A higher time-averaged serum HS-CRP level, the occurrence of cardiovascular events, infection episodes, and EPS were important predictors of dropout. The receiver operating characteristic analysis verified that the value of the time-average HS-CRP level in predicting the 5-year mortality and dropout was superior to a single serum baseline HS-CRP level. This study shows that the time-averaged serum HS-CRP level is a better marker than a single baseline measurement in predicting the 5-year mortality and dropout in PD patients.

  17. Optical Fibre Beam Delivery of High Average Power NEODYMIUM:YAG Laser Radiation

    Science.gov (United States)

    Boechat, Alvaro A. P.

    Available from UMI in association with The British Library. This thesis presents a study of the waveguiding properties of large core (200-1000mum core diameter), relatively short length (5-50m) multimode optical fibres used for delivery of Nd:YAG laser radiation at a wavelength of 1.06mum. A major objective of the study was to provide design information for beam delivery systems used in high power materials processing application. Experimental and theoretical investigation of the optical losses produced by bending the fibre lead to a model which can be used to predict the magnitude of the bend loss as a function of launching conditions, bend geometry and fibre parameters. The study confirms the importance of using large numerical aperture, small core diameter fibres to minimise losses. It has been shown that the beam output near field profile from a fibre is a function of the launching conditions. Theoretical and experimental study of the effect for both step and graded index fibres is presented. Geometric optics and phase space theory was used to develop a model in which a relationship between input and output beam quality from a graded index fibre was established. The results showed that there is an optimum launching condition for which the beam quality may be preserved for fibres with quadratic index profiles. The effect of curvature induced mode coupling on beam quality has been studied experimentally, and compared with intrinsic mode coupling effects. The study was supported by the development of a simple theoretical mode coupling model. Finally, a new monitoring technique for beam delivery systems was developed, based on detection of power in the fibre cladding. Applications include determining laser -fibre coupling efficiency, fibre integrity monitoring, and providing real time process information.

  18. High average power and energy microsecond pulse generation from an erbium-doped fluoride fiber MOPA system.

    Science.gov (United States)

    Luo, Hongyu; Li, Jianfneg; Xie, Jitao; Zhai, Bo; Wei, Chen; Liu, Yong

    2016-12-12

    We reported a high average power and energy microsecond pulse erbium-doped fluoride fiber MOPA system centered at 2786.8 nm. The master oscillator was a passively Q-switched erbium-doped fluoride fiber laser based on SESAM in a linear cavity. Then a one-stage erbium-doped fluoride fiber amplifier was used to boost its average output power to 4.2 W and pulse energy to 58.87 μJ. The pulse duration and repetition rate were 2.29 µs and 71.73 kHz, respectively. To the best of our knowledge, the achieved average output power and pulse energy are the recorded levels for the passively Q-switched fiber lasers at 3 μm wavelength region.

  19. The Effect of High School Socioeconomic Status on the Predictive Validity of SAT Scores and High School Grade-Point Average

    Science.gov (United States)

    Zwick, Rebecca; Himelfarb, Igor

    2011-01-01

    Research has often found that, when high school grades and SAT scores are used to predict first-year college grade-point average (FGPA) via regression analysis, African-American and Latino students, are, on average, predicted to earn higher FGPAs than they actually do. Under various plausible models, this phenomenon can be explained in terms of…

  20. Computations of longitudinal electron dynamics in the recirculating cw RF accelerator-recuperator for the high average power FEL

    Science.gov (United States)

    Sokolov, A. S.; Vinokurov, N. A.

    1994-03-01

    The use of optimal longitudinal phase-energy motion conditions for bunched electrons in a recirculating RF accelerator gives the possibility to increase the final electron peak current and, correspondingly, the FEL gain. The computer code RECFEL, developed for simulations of the longitudinal compression of electron bunches with high average current, essentially loading the cw RF cavities of the recirculator-recuperator, is briefly described and illustrated by some computational results.

  1. High average power picosecond pulse and supercontinuum generation from a thulium-doped, all-fiber amplifier.

    Science.gov (United States)

    Liu, Jiang; Xu, Jia; Liu, Kun; Tan, Fangzhou; Wang, Pu

    2013-10-15

    We demonstrate a high-power, picosecond, thulium-doped, all-fiber master oscillator power amplifier with average power of 120.4 W. The compact fiber oscillator is carefully designed with high repetition rate for the purpose of overcoming the detrimental effects of fiber nonlinearity in the later fiber amplifiers. The pulse duration of 16 ps at 333.75 MHz repetition rate results in a peak power of 22.5 kW in the final fiber power amplifier. To the best of our knowledge, this is the first demonstration of average power exceeding 100 W from an ultrashort pulse laser at 2 μm wavelength. On the other hand, by decreasing the fiber oscillator repetition rate and pulse duration for enhancing the fiber nonlinearity effects, we also demonstrate a high-power supercontinuum source with average power of 36 W from 1.95 μm to beyond 2.4 μm in the final fiber power amplifier.

  2. Effects of Visible and Invisible Hyperlinks on Vocabulary Acquisition and Reading Comprehension for High- and Average-Foreign Language Achievers

    Directory of Open Access Journals (Sweden)

    Ofelia R. Nikolova

    2004-12-01

    Full Text Available This study investigated the effects of visible and invisible links for annotated words in a computer module for learning French on the vocabulary acquisition and reading comprehension of two types of students – high – and average-achievers. Two hundred and sixty four second-semester students of French were identified as high- or average-achievers. Each type of students was then randomly assigned to two groups – with visible or invisible hyperlinks. All students were instructed to read a short passage in French (181 words for general comprehension and allowed to consult the annotated words (made visible by bold face for the visible links group as much as they needed. The students took a vocabulary pretest and an immediate and delayed (two weeks vocabulary and reading comprehension posttest. The results of the study showed that average- achievers benefited more from the visible links for vocabulary acquisition and reading comprehension than high-achievers. The results are discussed in light of second language acquisition and gifted-student theories and suggestions for future research are made.

  3. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Science.gov (United States)

    Stevens, Jens T; Safford, Hugh D; North, Malcolm P; Fried, Jeremy S; Gray, Andrew N; Brown, Peter M; Dolanc, Christopher R; Dobrowski, Solomon Z; Falk, Donald A; Farris, Calvin A; Franklin, Jerry F; Fulé, Peter Z; Hagmann, R Keala; Knapp, Eric E; Miller, Jay D; Smith, Douglas F; Swetnam, Thomas W; Taylor, Alan H

    Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA) program reflects the timing of historical high-severity (i.e. stand-replacing) fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1) the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2) recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  4. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Directory of Open Access Journals (Sweden)

    Jens T Stevens

    Full Text Available Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA program reflects the timing of historical high-severity (i.e. stand-replacing fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1 the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2 recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  5. High-repetition rate industrial TEA CO2 laser with average output power of 1.5 kW

    Science.gov (United States)

    Wan, Chongyi; Liu, Shiming; Zhou, Jinwen; Qi, Jilan; Yang, Xiaola; Wu, Jin; Tan, Rongqing; Wang, Lichun; Mei, Qichu

    1995-03-01

    High power high repetition rate TEA CO2 laser has potential importance in material processing such as shock hardening, glazing, drilling, welding, and cutting for high damage threshold materials, as well as in chemical reaction and isotope separation. This paper describes a transverse-flow closed-cycle UV-preionized TEA CO2 laser with peak pulse power of 20 MW, maximum average power of 1.5 KW at repetition rate of 300 HZ. The laser has compact constructure of gas flow circulation system using tangential fans. With addition of small amounts of H2 and CO to the normal CO2-N2-He gas mixture, one filling sealed operating lifetime is up to millions of pulses. A novel spark gap switch has been developed for very high repetition rate laser discharge in the condition of high pulse power.

  6. Averaged Electroencephalic Audiometry in Infants

    Science.gov (United States)

    Lentz, William E.; McCandless, Geary A.

    1971-01-01

    Normal, preterm, and high-risk infants were tested at 1, 3, 6, and 12 months of age using averaged electroencephalic audiometry (AEA) to determine the usefulness of AEA as a measurement technique for assessing auditory acuity in infants, and to delineate some of the procedural and technical problems often encountered. (KW)

  7. Edge-facet pumped, multi-aperture, thin-disk laser geometry for very high average power output scaling

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Luis E.

    2004-12-21

    The average power output of a laser is scaled, to first order, by increasing the transverse dimension of the gain medium while increasing the thickness of an index matched light guide proportionately. Strategic facets cut at the edges of the laminated gain medium provide a method by which the pump light introduced through edges of the composite structure is trapped and passes through the gain medium repeatedly. Spontaneous emission escapes the laser volume via these facets. A multi-faceted disk geometry with grooves cut into the thickness of the gain medium is optimized to passively reject spontaneous emission generated within the laser material, which would otherwise be trapped and amplified within the high index composite disk. Such geometry allows the useful size of the laser aperture to be increased, enabling the average laser output power to be scaled.

  8. High average daily intake of PCDD/Fs and serum levels in residents living near a deserted factory producing pentachlorophenol (PCP) in Taiwan: Influence of contaminated fish consumption

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.C. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Research Center of Environmental Trace Toxic Substances, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Lin, W.T. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Liao, P.C. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Research Center of Environmental Trace Toxic Substances, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Su, H.J. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Research Center of Environmental Trace Toxic Substances, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Chen, H.L. [Department of Industrial Safety and Health, Hung Kuang University, Taichung, 34 Chung Chie Rd. Sha Lu, Taichung 433, Taiwan (China)]. E-mail: hsiulin@sunrise.hk.edu.tw

    2006-05-15

    An abandoned pentachlorophenol plant and nearby area in southern Taiwan was heavily contaminated by dioxins, impurities formed in the PCP production process. The investigation showed that the average serum PCDD/Fs of residents living nearby area (62.5 pg WHO-TEQ/g lipid) was higher than those living in the non-polluted area (22.5 and 18.2 pg WHO-TEQ/g lipid) (P < 0.05). In biota samples, average PCDD/F of milkfish in sea reservoir (28.3 pg WHO-TEQ/g) was higher than those in the nearby fish farm (0.15 pg WHO-TEQ/g), and Tilapia and shrimp showed the similar trend. The average daily PCDD/Fs intake of 38% participants was higher than 4 pg WHO-TEQ/kg/day suggested by the world health organization. Serum PCDD/F was positively associated with average daily intake (ADI) after adjustment for age, sex, BMI, and smoking status. In addition, a prospective cohort study is suggested to determine the long-term health effects on the people living near factory. - Inhabitants living near a deserted PCP factory are exposed to high PCDD/F levels.

  9. Screening for hepatitis C in average and high-risk populations of Qatar using rapid point-of-care testing

    Science.gov (United States)

    Al Kaabi, Saad; John, Anil K; Al Dweik, Nazeeh; Ullah Wani, Hameed; Babu Thandassary, Ragesh; Derbala, Moutaz F; Al Ejji, Khalid; Sultan, Khaleel; Pasic, Fuad; Al Mohannadi, Munnera; Yacoub, Rafae; Butt, Mohd Tariq; Singh, Rajvir

    2015-01-01

    Background Screening for hepatitis C has been found to be beneficial in high-risk individuals and ‘baby boomers’. Objective Our aim was to screen for hepatitis C in average and high-risk individuals and compare the disease characteristics and response to treatment among the screened group (SG) and non-screened group (NSG). Method Community-based screening for hepatitis C was done in the average and high-risk populations of Qatar. Screening was done using rapid point-of-care testing. All patients with stage 1 fibrosis on liver biopsy were treated with pegylated interferon and ribavirin. Results In total, 13,704 people were screened and 272 (2%, 95% CI (1.8–2.2%) had positive antibodies to hepatitis C. During the same period, 237 non-screened patients (NSG) with hepatitis C were referred for treatment. Alanine and aspartate aminotransferases (ALT, AST) and overall fibrosis were significantly lower in the SG as compared with the NSG (p = 0.04, 0.04 and 0.01, respectively). The response to treatment was similar in the SG as compared with the NSG (sustained viral response 61.7 % versus 69.1%, p = 0.55). Average-risk patients had significantly lower ALT levels (p = 0.04) but had similar response to treatment as the high-risk individuals (sustained viral response 63.2 % versus 61%, p = 0.87). Conclusion Screening detects hepatitis C with lesser fibrosis but does not result in better response to pegylated interferon and ribavirin as compared with non-screened patients. PMID:26279845

  10. A satellite snow depth multi-year average derived from SSM/I for the high latitude regions

    Science.gov (United States)

    Biancamaria, S.; Mognard, N.M.; Boone, A.; Grippa, M.; Josberger, E.G.

    2008-01-01

    The hydrological cycle for high latitude regions is inherently linked with the seasonal snowpack. Thus, accurately monitoring the snow depth and the associated aerial coverage are critical issues for monitoring the global climate system. Passive microwave satellite measurements provide an optimal means to monitor the snowpack over the arctic region. While the temporal evolution of snow extent can be observed globally from microwave radiometers, the determination of the corresponding snow depth is more difficult. A dynamic algorithm that accounts for the dependence of the microwave scattering on the snow grain size has been developed to estimate snow depth from Special Sensor Microwave/Imager (SSM/I) brightness temperatures and was validated over the U.S. Great Plains and Western Siberia. The purpose of this study is to assess the dynamic algorithm performance over the entire high latitude (land) region by computing a snow depth multi-year field for the time period 1987-1995. This multi-year average is compared to the Global Soil Wetness Project-Phase2 (GSWP2) snow depth computed from several state-of-the-art land surface schemes and averaged over the same time period. The multi-year average obtained by the dynamic algorithm is in good agreement with the GSWP2 snow depth field (the correlation coefficient for January is 0.55). The static algorithm, which assumes a constant snow grain size in space and time does not correlate with the GSWP2 snow depth field (the correlation coefficient with GSWP2 data for January is - 0.03), but exhibits a very high anti-correlation with the NCEP average January air temperature field (correlation coefficient - 0.77), the deepest satellite snow pack being located in the coldest regions, where the snow grain size may be significantly larger than the average value used in the static algorithm. The dynamic algorithm performs better over Eurasia (with a correlation coefficient with GSWP2 snow depth equal to 0.65) than over North America

  11. Design of an L-band normally conducting RF gun cavity for high peak and average RF power

    Science.gov (United States)

    Paramonov, V.; Philipp, S.; Rybakov, I.; Skassyrskaya, A.; Stephan, F.

    2017-05-01

    To provide high quality electron bunches for linear accelerators used in free electron lasers and particle colliders, RF gun cavities operate with extreme electric fields, resulting in a high pulsed RF power. The main L-band superconducting linacs of such facilities also require a long RF pulse length, resulting in a high average dissipated RF power in the gun cavity. The newly developed cavity based on the proven advantages of the existing DESY RF gun cavities, underwent significant changes. The shape of the cells is optimized to reduce the maximal surface electric field and RF loss power. Furthermore, the cavity is equipped with an RF probe to measure the field amplitude and phase. The elaborated cooling circuit design results in a lower temperature rise on the cavity RF surface and permits higher dissipated RF power. The paper presents the main solutions and results of the cavity design.

  12. Plasma wakefield excitation by incoherent laser pulses: a path towards high-average power laser-plasma accelerators

    CERN Document Server

    Benedetti, C; Esarey, E; Leemans, W P

    2014-01-01

    In a laser plasma accelerator (LPA), a short and intense laser pulse propagating in a plasma drives a wakefield (a plasma wave with a relativistic phase velocity) that can sustain extremely large electric fields, enabling compact accelerating structures. Potential LPA applications include compact radiation sources and high energy linear colliders. We propose and study plasma wave excitation by an incoherent combination of a large number of low energy laser pulses (i.e., without constraining the pulse phases). We show that, in spite of the incoherent nature of electromagnetic fields within the volume occupied by the pulses, the excited wakefield is regular and its amplitude is comparable or equal to that obtained using a single, coherent pulse with the same energy. These results provide a path to the next generation of LPA-based applications, where incoherently combined multiple pulses may enable high repetition rate, high average power LPAs.

  13. The value of time-averaged serum high-sensitivity C-reactive protein in prediction of mortality and dropout in peritoneal dialysis patients

    Directory of Open Access Journals (Sweden)

    Liu SH

    2017-08-01

    Full Text Available Shou-Hsuan Liu,1–3,* Chao-Yu Chen,1,* Yi-Jung Li,1,2 Hsin-Hsu Wu,1,2 Chan-Yu Lin,1 Yung-Chang Chen,1 Ming-Yang Chang,1 Hsiang-Hao Hsu,1 Cheng-Lung Ku,2,3 Ya-Chung Tian1 1Kidney Research Center, Department of Nephrology, Lin-Kou Chang Gung Memorial Hospital and Department of Medicine, 2Graduate Institute of Clinical Medical Sciences, 3Laboratory of Human Immunology and Infectious Diseases, Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan *These authors contributed equally to this work Purpose: C-reactive protein (CRP is a useful biomarker for prediction of long-term outcomes in patients undergoing chronic dialysis. This observational cohort study evaluated whether the time-averaged serum high-sensitivity CRP (HS-CRP level was a better predictor of clinical outcomes than a single HS-CRP level in patients undergoing peritoneal dialysis (PD. Patients and methods: We classified 335 patients into three tertiles according to the time-averaged serum HS-CRP level and followed up regularly from January 2010 to December 2014. Clinical outcomes such as cardiovascular events, infection episodes, newly developed malignancy, encapsulating peritoneal sclerosis (EPS, dropout (death plus conversion to hemodialysis, and mortality were assessed. Results: During a 5-year follow-up, 164 patients (49.0% ceased PD; this included 52 patient deaths (15.5%, 100 patients (29.9% who converted to hemodialysis, and 12 patients (3.6% who received a kidney transplantation. The Kaplan–Meier survival analysis and log-rank test revealed a significantly worse survival accumulation in patients with high time-average HS-CRP levels. A multivariate Cox regression analysis revealed that a higher time-averaged serum HS-CRP level, older age, and the occurrence of cardiovascular events were independent mortality predictors. A higher time-averaged serum HS-CRP level, the occurrence of cardiovascular events, infection episodes, and EPS were

  14. TECATE - a code for anisotropic thermoelasticity in high-average-power laser technology. Phase 1 final report

    Energy Technology Data Exchange (ETDEWEB)

    Gelinas, R.J.; Doss, S.K.; Carlson, N.N.

    1985-01-01

    This report describes a totally Eulerian code for anisotropic thermoelasticity (code name TECATE) which may be used in evaluations of prospective crystal media for high-average-power lasers. The present TECATE code version computes steady-state distributions of material temperatures, stresses, strains, and displacement fields in 2-D slab geometry. Numerous heat source and coolant boundary condition options are available in the TECATE code for laser design considerations. Anisotropic analogues of plane stress and plane strain evaluations can be executed for any and all crystal symmetry classes. As with all new and/or large physics codes, it is likely that some code imperfections will emerge at some point in time.

  15. High-Throughput Laser Peening of Metals Using a High-Average-Power Nd: Glass Laser System

    Energy Technology Data Exchange (ETDEWEB)

    Dane, C.B.; Hackel, L.A.; Halpin, J.; Daly, J.; Harrisson, J.; Harris, J.

    1999-11-01

    Laser shot peening, a surface treatment for metals, is known to induce residual compressive stresses to depths of over 1 mm providing improved component resistance to various forms of failure. Recent information also suggests that thermal relaxation of the laser induced stress is significantly less than that experienced by other forms of surface stressing that involve significantly higher levels of cold work. We have developed a unique solid state laser technology employing Nd:glass amplifier slabs and SBS phase conjugation that enables this process to move into high throughput production processing.

  16. Iterative Bayesian Model Averaging: a method for the application of survival analysis to high-dimensional microarray data

    Directory of Open Access Journals (Sweden)

    Raftery Adrian E

    2009-02-01

    Full Text Available Abstract Background Microarray technology is increasingly used to identify potential biomarkers for cancer prognostics and diagnostics. Previously, we have developed the iterative Bayesian Model Averaging (BMA algorithm for use in classification. Here, we extend the iterative BMA algorithm for application to survival analysis on high-dimensional microarray data. The main goal in applying survival analysis to microarray data is to determine a highly predictive model of patients' time to event (such as death, relapse, or metastasis using a small number of selected genes. Our multivariate procedure combines the effectiveness of multiple contending models by calculating the weighted average of their posterior probability distributions. Our results demonstrate that our iterative BMA algorithm for survival analysis achieves high prediction accuracy while consistently selecting a small and cost-effective number of predictor genes. Results We applied the iterative BMA algorithm to two cancer datasets: breast cancer and diffuse large B-cell lymphoma (DLBCL data. On the breast cancer data, the algorithm selected a total of 15 predictor genes across 84 contending models from the training data. The maximum likelihood estimates of the selected genes and the posterior probabilities of the selected models from the training data were used to divide patients in the test (or validation dataset into high- and low-risk categories. Using the genes and models determined from the training data, we assigned patients from the test data into highly distinct risk groups (as indicated by a p-value of 7.26e-05 from the log-rank test. Moreover, we achieved comparable results using only the 5 top selected genes with 100% posterior probabilities. On the DLBCL data, our iterative BMA procedure selected a total of 25 genes across 3 contending models from the training data. Once again, we assigned the patients in the validation set to significantly distinct risk groups (p

  17. Investigation of cognitive abilities related to reading and spelling in Korean: readers with high, average, and low skill levels.

    Science.gov (United States)

    Park, Hyun-Rin; Uno, Akira

    2012-11-01

    In this study, we investigated the characteristics of cognitive abilities as predictors of Korean reading and spelling ability, and the characteristics of the cognition of reading difficulty in Korean. In 103 Korean third-grade children, we tested ability to read and spell, nonverbal intelligence, vocabulary size, phonological cognitive processing, visual cognitive processing, and naming speed. Our results indicated that receptive vocabulary, phoneme awareness, and naming speed served as factors for predicting reading test score; receptive vocabulary served as a factor for predicting spelling test score. We found that low reading-level groups had significantly slower performance on the naming speed task and lower scores on the receptive vocabulary test, as compared with the other groups (average and high reading-level groups). The present results have implications concerning useful tasks for screening for Korean poor readers. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Status of the High Average Power Diode-Pumped Solid State Laser Development at HiLASE

    Directory of Open Access Journals (Sweden)

    Ondřej Novák

    2015-09-01

    Full Text Available An overview of the latest developments of kilowatt-level diode pumped solid state lasers for advanced applications at the HiLASE Centre is presented. An overview of subcontracted and in-house-developed laser beamlines is presented. The aim of development is to build kW-class beamlines delivering picosecond pulses between 1- and 100-kHz repetition rates and high-energy nanosecond pulses at 10 Hz. The picosecond beamlines are based on Yb:YAG thin-disk amplifiers and chirped pulse amplification. The current status of the beamlines’ performance is reported. The advantages of zero-phonon line and pulsed pumping are demonstrated with respect to efficiency, thin disk temperature and beam quality. New diagnostics methods supporting the high average power lasers’ development, such as the high-resolution spectroscopy of Yb-doped materials, in situ thin disk deformation measurements, single-shot M2 measurement, realization of wavefront correction by a deformable mirror and the laser performance of a new mixed garnet ceramics, are described. The energetic, thermal and fluid-mechanical numerical modeling for the optimization of the multi-slab amplifiers is also described.

  19. High Recharge Areas in the Choushui River Alluvial Fan (Taiwan Assessed from Recharge Potential Analysis and Average Storage Variation Indexes

    Directory of Open Access Journals (Sweden)

    Jui-Pin Tsai

    2015-03-01

    Full Text Available High recharge areas significantly influence the groundwater quality and quantity in regional groundwater systems. Many studies have applied recharge potential analysis (RPA to estimate groundwater recharge potential (GRP and have delineated high recharge areas based on the estimated GRP. However, most of these studies define the RPA parameters with supposition, and this represents a major source of uncertainty for applying RPA. To objectively define the RPA parameter values without supposition, this study proposes a systematic method based on the theory of parameter identification. A surrogate variable, namely the average storage variation (ASV index, is developed to calibrate the RPA parameters, because of the lack of direct GRP observations. The study results show that the correlations between the ASV indexes and computed GRP values improved from 0.67 before calibration to 0.85 after calibration, thus indicating that the calibrated RPA parameters represent the recharge characteristics of the study area well; these data also highlight how defining the RPA parameters with ASV indexes can help to improve the accuracy. The calibrated RPA parameters were used to estimate the GRP distribution of the study area, and the GRP values were graded into five levels. High and excellent level areas are defined as high recharge areas, which composed 7.92% of the study area. Overall, this study demonstrates that the developed approach can objectively define the RPA parameters and high recharge areas of the Choushui River alluvial fan, and the results should serve as valuable references for the Taiwanese government in their efforts to conserve the groundwater quality and quantity of the study area.

  20. The Baryon Cycle at High Redshifts: Effects of Galactic Winds on Galaxy Evolution in Overdense and Average Regions

    Science.gov (United States)

    Sadoun, Raphael; Shlosman, Isaac; Choi, Jun-Hwan; Romano-Díaz, Emilio

    2016-10-01

    We employ high-resolution cosmological zoom-in simulations focusing on a high-sigma peak and an average cosmological field at z ˜ 6-12 in order to investigate the influence of environment and baryonic feedback on galaxy evolution in the reionization epoch. Strong feedback, e.g., galactic winds, caused by elevated star formation rates (SFRs) is expected to play an important role in this evolution. We compare different outflow prescriptions: (i) constant wind velocity (CW), (ii) variable wind scaling with galaxy properties (VW), and (iii) no outflows (NW). The overdensity leads to accelerated evolution of dark matter and baryonic structures, absent from the “normal” region, and to shallow galaxy stellar mass functions at the low-mass end. Although CW shows little dependence on the environment, the more physically motivated VW model does exhibit this effect. In addition, VW can reproduce the observed specific SFR (sSFR) and the sSFR-stellar mass relation, which CW and NW fail to satisfy simultaneously. Winds also differ substantially in affecting the state of the intergalactic medium (IGM). The difference lies in the volume-filling factor of hot, high-metallicity gas, which is near unity for CW, while such gas remains confined in massive filaments for VW, and locked up in galaxies for NW. Such gas is nearly absent from the normal region. Although all wind models suffer from deficiencies, the VW model seems to be promising in correlating the outflow properties with those of host galaxies. Further constraints on the state of the IGM at high z are needed to separate different wind models.

  1. Process optimization in high-average-power ultrashort pulse laser microfabrication: how laser process parameters influence efficiency, throughput and quality

    Science.gov (United States)

    Schille, Joerg; Schneider, Lutz; Loeschner, Udo

    2015-09-01

    In this paper, laser processing of technical grade stainless steel and copper using high-average-power ultrashort pulse lasers is studied in order to gain deeper insight into material removal for microfabrication. A high-pulse repetition frequency picosecond and femtosecond laser is used in conjunction with high-performance galvanometer scanners and an in-house developed two-axis polygon scanner system. By varying the processing parameters such as wavelength, pulse length, fluence and repetition rate, cavities of standardized geometry are fabricated and analyzed. From the depths of the cavities produced, the ablation rate and removal efficiency are estimated. In addition, the quality of the cavities is evaluated by means of scanning electron microscope micrographs or rather surface roughness measurements. From the results obtained, the influence of the machining parameters on material removal and machining quality is discussed. In addition, it is shown that both material removal rate and quality increase by using femtosecond compared to picosecond laser pulses. On stainless steel, a maximum throughput of 6.81 mm3/min is achieved with 32 W femtosecond laser powers; if using 187 W picosecond laser powers, the maximum is 15.04 mm3/min, respectively. On copper, the maximum throughputs are 6.1 mm3/min and 21.4 mm3/min, obtained with 32 W femtosecond and 187 W picosecond laser powers. The findings indicate that ultrashort pulses in the mid-fluence regime yield most efficient material removal. In conclusion, from the results of this analysis, a range of optimum processing parameters are derived feasible to enhance machining efficiency, throughput and quality in high-rate micromachining. The work carried out here clearly opens the way to significant industrial applications.

  2. The Baryon Cycle at High Redshifts: Effects of Galactic Winds on Galaxy Evolution in Overdense and Average Regions

    CERN Document Server

    Sadoun, Raphael; Choi, Jun-Hwan; Romano-Díaz, Emilio

    2015-01-01

    We use high-resolution cosmological zoom-in simulations in order to analyze galaxy evolution at redshifts z~6-12 in highly-overdense 5 sigma density peaks. Strong stellar feedback, in the form of galactic winds, is expected to play an important role in the evolution of these regions. We investigate the effects of these winds by comparing different galactic outflow prescriptions, including (i) a constant velocity model (CW), (ii) a variable velocity model scaling with galaxy properties (VW), and (iii) a model with no outflows (NW). The CW model is also applied to a simulation of an average density region to study the impact of environment on galaxy evolution. A direct consequence of the overdensity is a shallow galaxy mass function slope at the low-mass end and an accelerated evolution of dark matter and baryonic structures. The overdensity hosts massive haloes, up to ~10^{12} Msun, with embedded galaxies up to ~10^{11} Msun in stellar mass by z~6, which are absent in the "normal" region. The CW model leads to...

  3. Analysis of high-frequency energy in long-term average spectra of singing, speech, and voiceless fricatives.

    Science.gov (United States)

    Monson, Brian B; Lotto, Andrew J; Story, Brad H

    2012-09-01

    The human singing and speech spectrum includes energy above 5 kHz. To begin an in-depth exploration of this high-frequency energy (HFE), a database of anechoic high-fidelity recordings of singers and talkers was created and analyzed. Third-octave band analysis from the long-term average spectra showed that production level (soft vs normal vs loud), production mode (singing vs speech), and phoneme (for voiceless fricatives) all significantly affected HFE characteristics. Specifically, increased production level caused an increase in absolute HFE level, but a decrease in relative HFE level. Singing exhibited higher levels of HFE than speech in the soft and normal conditions, but not in the loud condition. Third-octave band levels distinguished phoneme class of voiceless fricatives. Female HFE levels were significantly greater than male levels only above 11 kHz. This information is pertinent to various areas of acoustics, including vocal tract modeling, voice synthesis, augmentative hearing technology (hearing aids and cochlear implants), and training/therapy for singing and speech.

  4. Performance study of highly efficient 520 W average power long pulse ceramic Nd:YAG rod laser

    Science.gov (United States)

    Choubey, Ambar; Vishwakarma, S. C.; Ali, Sabir; Jain, R. K.; Upadhyaya, B. N.; Oak, S. M.

    2013-10-01

    We report the performance study of a 2% atomic doped ceramic Nd:YAG rod for long pulse laser operation in the millisecond regime with pulse duration in the range of 0.5-20 ms. A maximum average output power of 520 W with 180 J maximum pulse energy has been achieved with a slope efficiency of 5.4% using a dual rod configuration, which is the highest for typical lamp pumped ceramic Nd:YAG lasers. The laser output characteristics of the ceramic Nd:YAG rod were revealed to be nearly equivalent or superior to those of high-quality single crystal Nd:YAG rod. The laser pump chamber and resonator were designed and optimized to achieve a high efficiency and good beam quality with a beam parameter product of 16 mm mrad (M2˜47). The laser output beam was efficiently coupled through a 400 μm core diameter optical fiber with 90% overall transmission efficiency. This ceramic Nd:YAG laser will be useful for various material processing applications in industry.

  5. Average exceptional Lie and Coxeter group hierarchies with special reference to the standard model of high energy particle physics

    Energy Technology Data Exchange (ETDEWEB)

    El Naschie, M.S. [King Abdullah Al Saud Institute of Nano and Advanced Technologies, Riyadh (Saudi Arabia)], E-mail: Chaossf@aol.com

    2008-08-15

    The notions of the order of a symmetry group may be extended to that of an average, non-integer order. Building on this extension, it can be shown that the five classical exceptional Lie symmetry groups could be extended to a hierarchy, the total sum of which is four times {alpha}-bar{sub 0}=137+k{sub 0} of the electromagnetic field. Subsequently it can be shown that all known and conjectured physical fields may be derived by E-infinity transfinite scaling transformation. Consequently E{sub 8}E{sub 8} exceptional Lie symmetry groups manifold, the SL(2,7){sub c} holographic modular curve boundary {gamma}(7), Einstein-Kaluza gravity R{sup (n=4)} and R{sup (n=5)} as well as the electromagnetic field are all topological transformations of each other. It is largely a matter of mathematical taste to choose E{sub 8} or the electromagnetic field associated with {alpha}-bar{sub 0} as derived or as fundamental. However since E{sub 8} has been extensively studied by the founding father of group theory and has recently been mapped completely, it seems beneficial to discuss at least high energy physics starting from the largest of the exceptional groups.

  6. The inclusion of pupils with special educational needs in Early Stimulation age into the regular classroom environment, at Nursery Schools, of an average municipality Vale dos Sinos

    Directory of Open Access Journals (Sweden)

    Luciana Cátia Loose Pereira

    2012-03-01

    Full Text Available Inclusive education in Brazil has been widely discussed in all areas of the educational. The inclusion of pupils with special educational needs (SEN in mainstream schools is increasingly frequent, though still many aspects need to be rethought. This work aimed at checking how the subjects with SEN in Early Stimulation age, from zero to three years and 11 months are included into the regular classroom environment, at Nursery Schools, of an average municipality - Vale dos Sinos. This work involved a cross-sectional survey of quantitative and descriptive statistics. The data collection was carried out directly from a structured questionnaire with open and closed questions, directed to all principals of the thirteen Nursery Schools in the referred municipality. From the thirteen schools of the municipality only one did not take part of the research since there was no enrollment of children with special needs there, totalizing 46 children in processes of educational inclusion. From those, twelve children (26.8% were benefited with an Early Stimulation service maintained by the Association of Parents and Friends of Exceptional Children of that referred municipality, Thirty children (65,2% enrolled in school at the initiative of his own family e four children (8% by intervention of the Wakefield council. In this sense, we believe that the professionals of the Early Stimulation have the responsibility of promoting and conveying its importance and, mainly, the benefits of Early Stimulation for the whole development of individuals, as well as its contribution to a process of inclusive education.

  7. Highly turbulent solutions of the Lagrangian-averaged Navier-Stokes alpha model and their large-eddy-simulation potential.

    Science.gov (United States)

    Pietarila Graham, Jonathan; Holm, Darryl D; Mininni, Pablo D; Pouquet, Annick

    2007-11-01

    We compute solutions of the Lagrangian-averaged Navier-Stokes alpha - (LANS alpha ) model for significantly higher Reynolds numbers (up to Re approximately 8300 ) than have previously been accomplished. This allows sufficient separation of scales to observe a Navier-Stokes inertial range followed by a second inertial range specific to the LANS alpha model. Both fully helical and nonhelical flows are examined, up to Reynolds numbers of approximately 1300. Analysis of the third-order structure function scaling supports the predicted l3 scaling; it corresponds to a k-1 scaling of the energy spectrum for scales smaller than alpha. The energy spectrum itself shows a different scaling, which goes as k1. This latter spectrum is consistent with the absence of stretching in the subfilter scales due to the Taylor frozen-in hypothesis employed as a closure in the derivation of the LANS alpha model. These two scalings are conjectured to coexist in different spatial portions of the flow. The l3 [E(k) approximately k-1] scaling is subdominant to k1 in the energy spectrum, but the l3 scaling is responsible for the direct energy cascade, as no cascade can result from motions with no internal degrees of freedom. We demonstrate verification of the prediction for the size of the LANS alpha attractor resulting from this scaling. From this, we give a methodology either for arriving at grid-independent solutions for the LANS alpha model, or for obtaining a formulation of the large eddy simulation optimal in the context of the alpha models. The fully converged grid-independent LANS alpha model may not be the best approximation to a direct numerical simulation of the Navier-Stokes equations, since the minimum error is a balance between truncation errors and the approximation error due to using the LANS alpha instead of the primitive equations. Furthermore, the small-scale behavior of the LANS alpha model contributes to a reduction of flux at constant energy, leading to a shallower energy

  8. Phase Transformation and Thermal Stability of Aged Ti-Ni-Hf High Temperature Shape Memory Alloys

    Institute of Scientific and Technical Information of China (English)

    Xianglong MENG; Wei CAI; K.T.Lau; L.M.Zhou; Liancheng ZHAO

    2006-01-01

    The use of Ni-rich TiNiHf alloys as high temperature shape memory alloys(SMAs)through aging has been presented. For Ni-rich Ti80-xNixHf20 alloys, their phase transformation temperatures are averagely increased more than 100 K by aging at 823 K for 2 h. Especially for the alloys with Ni-content of 50.4 at. pct and 50.6 at. pct, their martensitic transformation start temperatures(Ms)are more than 473 K after aging. TEM observation confirmed that some fine particles precipitate from the matrix during aging. The aged Ni-rich TiNiHf SMAs show the better thermal stability of phase transformation temperatures than the solutiontreated TiNiHf alloys. The fine particles precipitated during aging should be responsible for the increase of phase transformation temperatures and its high stability.

  9. Associations between age at first calving, rearing average daily weight gain, herd milk yield and dairy herd production, reproduction, and profitability.

    Science.gov (United States)

    Krpálková, L; Cabrera, V E; Kvapilík, J; Burdych, J; Crump, P

    2014-10-01

    The objective of this study was to evaluate the associations of variable intensity in rearing dairy heifers on 33 commercial dairy herds, including 23,008 cows and 18,139 heifers, with age at first calving (AFC), average daily weight gain (ADG), and milk yield (MY) level on reproduction traits and profitability. Milk yield during the production period was analyzed relative to reproduction and economic parameters. Data were collected during a 1-yr period (2011). The farms were located in 12 regions in the Czech Republic. The results show that those herds with more intensive rearing periods had lower conception rates among heifers at first and overall services. The differences in those conception rates between the group with the greatest ADG (≥0.800 kg/d) and the group with the least ADG (≤0.699 kg/d) were approximately 10 percentage points in favor of the least ADG. All the evaluated reproduction traits differed between AFC groups. Conception at first and overall services (cows) was greatest in herds with AFC ≥800 d. The shortest days open (105 d) and calving interval (396 d) were found in the middle AFC group (799 to 750 d). The highest number of completed lactations (2.67) was observed in the group with latest AFC (≥800 d). The earliest AFC group (≤749 d) was characterized by the highest depreciation costs per cow at 8,275 Czech crowns (US$414), and the highest culling rate for cows of 41%. The most profitable rearing approach was reflected in the middle AFC (799 to 750 d) and middle ADG (0.799 to 0.700 kg) groups. The highest MY (≥8,500 kg) occurred with the earliest AFC of 780 d. Higher MY led to lower conception rates in cows, but the highest MY group also had the shortest days open (106 d) and a calving interval of 386 d. The same MY group had the highest cow depreciation costs, net profit, and profitability without subsidies of 2.67%. We conclude that achieving low AFC will not always be the most profitable approach, which will depend upon farm

  10. High Strength, Weldable Precipitation Aged Steels

    Science.gov (United States)

    Wilson, Alexander D.

    1987-03-01

    The family of plate steels represented by ASTM Specification A7101 is finding increasing applications. These low carbon, Cu-Ni-Cr-Mo-Cb, copper precipitation hardened steels have been identified by a number of designations over the years. During early development in the late 1960's and first commercial production in 1970, the steels were known as IN-787 (trademark of International Nickel Company).2 ASTM specifications were subsequently developed for structural (A710) and pressure vessel (A736) applications over ten years ago. More recent interest and application of this family of steels by the U.S. Navy has lead to development of a military specification MIL-S-24645 (SH),3 also initially known as "HSLA-80." Significant tonnage is being produced for the U.S. Navy as a replacement for HY80 (MIL-S-16216) in cruiser deck, bulkhead and hull applications.4 In these applications, the enhanced weldability and requirement of no preheat at this high strength and toughness level has been the main motivation for its use. Over the past 15 years, A710 type steels have also been used in a variety of applications, including off-shore platforms, pressure vessels, arctic linepipe valves and off-highway mining truck frames.

  11. Cancer screening with digital mammography for women at average risk for breast cancer, magnetic resonance imaging (MRI) for women at high risk: an evidence-based analysis.

    Science.gov (United States)

    2010-01-01

    The purpose of this review is to determine the effectiveness of 2 separate modalities, digital mammography (DM) and magnetic resonance imaging (MRI), relative to film mammography (FM), in the screening of women asymptomatic for breast cancer. A third analysis assesses the effectiveness and safety of the combination of MRI plus mammography (MRI plus FM) in screening of women at high risk. An economic analysis was also conducted. How does the sensitivity and specificity of DM compare to FM?How does the sensitivity and specificity of MRI compare to FM?How do the recall rates compare among these screening modalities, and what effect might this have on radiation exposure? What are the risks associated with radiation exposure?How does the sensitivity and specificity of the combination of MRI plus FM compare to either MRI or FM alone?What are the economic considerations? The effectiveness of FM with respect to breast cancer mortality in the screening of asymptomatic average- risk women over the age of 50 has been established. However, based on a Medical Advisory Secretariat review completed in March 2006, screening is not recommended for women between the ages of 40 and 49 years. Guidelines published by the Canadian Task Force on Preventive Care recommend mammography screening every 1 to 2 years for women aged 50 years and over, hence, the inclusion of such women in organized breast cancer screening programs. In addition to the uncertainty of the effectiveness of mammography screening from the age of 40 years, there is concern over the risks associated with mammographic screening for the 10 years between the ages of 40 and 49 years. The lack of effectiveness of mammography screening starting at the age of 40 years (with respect to breast cancer mortality) is based on the assumption that the ability to detect cancer decreases with increased breast tissue density. As breast density is highest in the premenopausal years (approximately 23% of postmenopausal and 53% of

  12. Mitochondrial DNA Marker EST00083 Is Not Associated with High vs. Average IQ in a German Sample.

    Science.gov (United States)

    Moises, Hans W.; Yang, Liu; Kohnke, Michael; Vetter, Peter; Neppert, Jurgen; Petrill, Stephen A.; Plomin, Robert

    1998-01-01

    Tested the association of a mitochondrial DNA marker (EST00083) with high IQ in a sample of 47 German adults with high IQ scores and 77 adults with IQs estimated at lower than 110. Results do not support the hypothesis that high IQ is associated with this marker. (SLD)

  13. High average daily intake of PCDD/Fs and serum levels in residents living near a deserted factory producing pentachlorophenol (PCP) in Taiwan: influence of contaminated fish consumption.

    Science.gov (United States)

    Lee, C C; Lin, W T; Liao, P C; Su, H J; Chen, H L

    2006-05-01

    An abandoned pentachlorophenol plant and nearby area in southern Taiwan was heavily contaminated by dioxins, impurities formed in the PCP production process. The investigation showed that the average serum PCDD/Fs of residents living nearby area (62.5 pg WHO-TEQ/g lipid) was higher than those living in the non-polluted area (22.5 and 18.2 pg WHO-TEQ/g lipid) (Pfarm (0.15 pg WHO-TEQ/g), and Tilapia and shrimp showed the similar trend. The average daily PCDD/Fs intake of 38% participants was higher than 4 pg WHO-TEQ/kg/day suggested by the world health organization. Serum PCDD/F was positively associated with average daily intake (ADI) after adjustment for age, sex, BMI, and smoking status. In addition, a prospective cohort study is suggested to determine the long-term health effects on the people living near factory.

  14. An Analysis of Java Programming Behaviors, Affect, Perceptions, and Syntax Errors among Low-Achieving, Average, and High-Achieving Novice Programmers

    Science.gov (United States)

    Rodrigo, Ma. Mercedes T.; Andallaza, Thor Collin S.; Castro, Francisco Enrique Vicente G.; Armenta, Marc Lester V.; Dy, Thomas T.; Jadud, Matthew C.

    2013-01-01

    In this article we quantitatively and qualitatively analyze a sample of novice programmer compilation log data, exploring whether (or how) low-achieving, average, and high-achieving students vary in their grasp of these introductory concepts. High-achieving students self-reported having the easiest time learning the introductory programming…

  15. An Analysis of Java Programming Behaviors, Affect, Perceptions, and Syntax Errors among Low-Achieving, Average, and High-Achieving Novice Programmers

    Science.gov (United States)

    Rodrigo, Ma. Mercedes T.; Andallaza, Thor Collin S.; Castro, Francisco Enrique Vicente G.; Armenta, Marc Lester V.; Dy, Thomas T.; Jadud, Matthew C.

    2013-01-01

    In this article we quantitatively and qualitatively analyze a sample of novice programmer compilation log data, exploring whether (or how) low-achieving, average, and high-achieving students vary in their grasp of these introductory concepts. High-achieving students self-reported having the easiest time learning the introductory programming…

  16. Aging, High Altitude, and Blood Pressure: A Complex Relationship.

    Science.gov (United States)

    Parati, Gianfranco; Ochoa, Juan Eugenio; Torlasco, Camilla; Salvi, Paolo; Lombardi, Carolina; Bilo, Grzegorz

    2015-06-01

    Parati, Gianfranco, Juan Eugenio Ochoa, Camilla Torlasco, Paolo Salvi, Carolina Lombardi, and Grzegorz Bilo. Aging, high altitude, and blood pressure: A complex relationship. High Alt Biol Med 16:97-109, 2015.--Both aging and high altitude exposure may induce important changes in BP regulation, leading to significant increases in BP levels. By inducing atherosclerotic changes, stiffening of large arteries, renal dysfunction, and arterial baroreflex impairment, advancing age may induce progressive increases in systolic BP levels, promoting development and progression of arterial hypertension. It is also known, although mainly from studies in young or middle-aged subjects, that exposure to high altitude may influence different mechanisms involved in BP regulation (i.e., neural central and reflex control of sympathetic activity), leading to important increases in BP levels. The evidence is less clear, however, on whether and to what extent advancing age may influence the BP response to acute or chronic high altitude exposure. This is a question not only of scientific interest but also of practical relevance given the consistent number of elderly individuals who are exposed for short time periods (either for leisure or work) or live permanently at high altitude, in whom arterial hypertension is frequently observed. This article will review the evidence available on the relationship between aging and blood pressure levels at high altitude, the pathophysiological mechanisms behind this complex association, as well as some questions of practical interest regarding antihypertensive treatment in elderly subjects, and the effects of antihypertensive drugs on blood pressure response during high altitude exposure.

  17. Age scope of high-risk population for esophageal cancer in Ci county

    Institute of Scientific and Technical Information of China (English)

    Zhi-Feng Chen; Jun Hou; Zhen-Wei Ding; Cui-Lan Guo; Cui-Yun Qiao; Guo-Hui Song; Shao-Sen Li; Jian-Hui Zhang; Yu-Tong He

    2005-01-01

    AIM: To define the age scope of high-risk population for esophageal cancer (EC) in Ci county.METHODS: The results of endoscopic examination of 2013 subjects, cytological screening of 16 763 persons and records of 9 265 patients with EC were analyzed by Ridit methods, the standard age group was 45-49 year group.RESULTS: The average age of patients with moderate esophageal epithelium dysplasia by endoscopic examination was 53.5 years, of severe esophageal epithelium dysplasia,51.4 years, early EC, 55.6 years. The average age of stage one severe epithelium dysplasia (SEEDI) by cytological screening was 51.2 years, of stage two severe epithelium esophageal dysplasia (SEED Ⅱ) 51.6 years, of advanced EC 61.7 years. In the group of 40-year olds,the value of Ridit by pathological diagnosis was 0.46, 95%CI, 0.45-0.47, that by cytological diagnosis was 0.45, 95%CI, 0.43-0.47. As the age increased at five-year intervals,the value of Ridit increased significantly.CONCLUSION: In Ci county of a high incidence area of EC, the age definition of high-risk population should be above 45 years.

  18. High-average-power 2 μm few-cycle optical parametric chirped pulse amplifier at 100 kHz repetition rate.

    Science.gov (United States)

    Shamir, Yariv; Rothhardt, Jan; Hädrich, Steffen; Demmler, Stefan; Tschernajew, Maxim; Limpert, Jens; Tünnermann, Andreas

    2015-12-01

    Sources of long wavelengths few-cycle high repetition rate pulses are becoming increasingly important for a plethora of applications, e.g., in high-field physics. Here, we report on the realization of a tunable optical parametric chirped pulse amplifier at 100 kHz repetition rate. At a central wavelength of 2 μm, the system delivered 33 fs pulses and a 6 W average power corresponding to 60 μJ pulse energy with gigawatt-level peak powers. Idler absorption and its crystal heating is experimentally investigated for a BBO. Strategies for further power scaling to several tens of watts of average power are discussed.

  19. Implementation of a reference-scaled average bioequivalence approach for highly variable generic drug products of agomelatine in Chinese subjects

    Directory of Open Access Journals (Sweden)

    Fang Tang

    2016-01-01

    Full Text Available The aim of this study was to apply the reference-scaled average bioequivalence (RSABE approach to evaluate the bioequivalence of 2 formulations of agomelatine, and to investigate the pharmacokinetic properties of agomelatine in Chinese healthy male subjects. This was performed in a single-dose, randomized-sequence, open-label, four-way crossover study with a one-day washout period between doses. Healthy Chinese males were randomly assigned to receive 25 mg of either the test or reference formulation. The formulations were considered bioequivalent if 90% confidence intervals (CIs for the log-transformed ratios and ratio of geometric means (GMR of AUC and Cmax of agomelatine were within the predetermined bioequivalence range based on RSABE method. Results showed that both of the 90% CIs for the log-transformed ratios of AUC and Cmax of 7-desmethyl-agomelatine and 3-hydroxy-agomelatine were within the predetermined bioequivalence range. The 90% CIs for natural log-transformed ratios of Cmax, AUC0–t and AUC0–∞ of agomelatine (104.42–139.86, 101.33–123.83 and 97.90–117.94 were within the RSABE acceptance limits, and 3-hydroxy-agomelatine (105.55–123.03, 101.95–109.10 and 101.72–108.70 and 7-desmethyl-agomelatine (104.50–125.23, 102.36–111.50 and 101.62–110.64 were within the FDA bioequivalence definition intervals (0.80–1.25 for AUC and 0.75–1.33 for Cmax. The RSABE approach was successful in evaluating the bioequivalence of these two formulations.

  20. High Resolution Topography of Age-Related Changes in Non-Rapid Eye Movement Sleep Electroencephalography.

    Directory of Open Access Journals (Sweden)

    Kate E Sprecher

    Full Text Available Sleeping brain activity reflects brain anatomy and physiology. The aim of this study was to use high density (256 channel electroencephalography (EEG during sleep to characterize topographic changes in sleep EEG power across normal aging, with high spatial resolution. Sleep was evaluated in 92 healthy adults aged 18-65 years old using full polysomnography and high density EEG. After artifact removal, spectral power density was calculated for standard frequency bands for all channels, averaged across the NREM periods of the first 3 sleep cycles. To quantify topographic changes with age, maps were generated of the Pearson's coefficient of the correlation between power and age at each electrode. Significant correlations were determined by statistical non-parametric mapping. Absolute slow wave power declined significantly with increasing age across the entire scalp, whereas declines in theta and sigma power were significant only in frontal regions. Power in fast spindle frequencies declined significantly with increasing age frontally, whereas absolute power of slow spindle frequencies showed no significant change with age. When EEG power was normalized across the scalp, a left centro-parietal region showed significantly less age-related decline in power than the rest of the scalp. This partial preservation was particularly significant in the slow wave and sigma bands. The effect of age on sleep EEG varies substantially by region and frequency band. This non-uniformity should inform the design of future investigations of aging and sleep. This study provides normative data on the effect of age on sleep EEG topography, and provides a basis from which to explore the mechanisms of normal aging as well as neurodegenerative disorders for which age is a risk factor.

  1. High Resolution Topography of Age-Related Changes in Non-Rapid Eye Movement Sleep Electroencephalography.

    Science.gov (United States)

    Sprecher, Kate E; Riedner, Brady A; Smith, Richard F; Tononi, Giulio; Davidson, Richard J; Benca, Ruth M

    2016-01-01

    Sleeping brain activity reflects brain anatomy and physiology. The aim of this study was to use high density (256 channel) electroencephalography (EEG) during sleep to characterize topographic changes in sleep EEG power across normal aging, with high spatial resolution. Sleep was evaluated in 92 healthy adults aged 18-65 years old using full polysomnography and high density EEG. After artifact removal, spectral power density was calculated for standard frequency bands for all channels, averaged across the NREM periods of the first 3 sleep cycles. To quantify topographic changes with age, maps were generated of the Pearson's coefficient of the correlation between power and age at each electrode. Significant correlations were determined by statistical non-parametric mapping. Absolute slow wave power declined significantly with increasing age across the entire scalp, whereas declines in theta and sigma power were significant only in frontal regions. Power in fast spindle frequencies declined significantly with increasing age frontally, whereas absolute power of slow spindle frequencies showed no significant change with age. When EEG power was normalized across the scalp, a left centro-parietal region showed significantly less age-related decline in power than the rest of the scalp. This partial preservation was particularly significant in the slow wave and sigma bands. The effect of age on sleep EEG varies substantially by region and frequency band. This non-uniformity should inform the design of future investigations of aging and sleep. This study provides normative data on the effect of age on sleep EEG topography, and provides a basis from which to explore the mechanisms of normal aging as well as neurodegenerative disorders for which age is a risk factor.

  2. High Resolution Topography of Age-Related Changes in Non-Rapid Eye Movement Sleep Electroencephalography

    Science.gov (United States)

    Sprecher, Kate E.; Riedner, Brady A.; Smith, Richard F.; Tononi, Giulio; Davidson, Richard J.; Benca, Ruth M.

    2016-01-01

    Sleeping brain activity reflects brain anatomy and physiology. The aim of this study was to use high density (256 channel) electroencephalography (EEG) during sleep to characterize topographic changes in sleep EEG power across normal aging, with high spatial resolution. Sleep was evaluated in 92 healthy adults aged 18–65 years old using full polysomnography and high density EEG. After artifact removal, spectral power density was calculated for standard frequency bands for all channels, averaged across the NREM periods of the first 3 sleep cycles. To quantify topographic changes with age, maps were generated of the Pearson’s coefficient of the correlation between power and age at each electrode. Significant correlations were determined by statistical non-parametric mapping. Absolute slow wave power declined significantly with increasing age across the entire scalp, whereas declines in theta and sigma power were significant only in frontal regions. Power in fast spindle frequencies declined significantly with increasing age frontally, whereas absolute power of slow spindle frequencies showed no significant change with age. When EEG power was normalized across the scalp, a left centro-parietal region showed significantly less age-related decline in power than the rest of the scalp. This partial preservation was particularly significant in the slow wave and sigma bands. The effect of age on sleep EEG varies substantially by region and frequency band. This non-uniformity should inform the design of future investigations of aging and sleep. This study provides normative data on the effect of age on sleep EEG topography, and provides a basis from which to explore the mechanisms of normal aging as well as neurodegenerative disorders for which age is a risk factor. PMID:26901503

  3. High average power 1314 nm Nd:YLF laser, passively Q-switched with V:YAG

    CSIR Research Space (South Africa)

    Botha, RC

    2013-03-01

    Full Text Available Stellenbosch University, P/Bag X1, Matieland 7602, South Africa 3National Laser Centre, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001, South Africa 4Physics Department, Carl von Ossietzky University, Oldenburg 26111, Germany 5...-shifted to the 1.5 μm region, which is useful for applications requiring eye-safe operation at high powers, such as Lidar and free-space optical com- munication [1]. Furthermore, 1314.0 nm (specifically the 657.0 nm harmonic) is required to probe the relevant...

  4. Interpreting Changes over Time in High School Average ACT® College Readiness Assessment Composite Scores and ACT College Readiness Benchmark Attainment Rates. ACT Research Report Series, 2013 (9)

    Science.gov (United States)

    Sawyer, Richard

    2013-01-01

    Education officials and journalists frequently track changes over time in the average ACT® College Readiness Assessment Composite scores and ACT College Readiness Benchmark attainment rates of individual high schools. Using standard statistical methods, I examined how often changes in these statistics are unambiguously positive or negative, rather…

  5. 2D Chaos in the Interaction of Inflation and Unemployment: Moving Averages and the Modeling of High Frequency Macrodynamics

    Directory of Open Access Journals (Sweden)

    Peter Flaschel

    2014-01-01

    Full Text Available The paper argues that applicable macro is high frequency macro and the data generating process is therefore to be modeled in continuous time. It exemplifies this with a misuse of a 2D period model of monetarist type which becomes extremely overshooting, allowing for routes to “chaos,” when iterated at low frequencies. Instead of such low frequency procedures, we augment the model by a Keynesian feedback chain (the real rate of interest channel to introduce local instability into the model. We also introduce heterogeneous opinion dynamics into it. The implied 4D dynamics are made bounded thereby, but seem to allow only complex limit cycles, with no transition towards strange attractors anymore.

  6. U.S. onroad transportation CO2 emissions analysis comparing highly resolved CO2 emissions and a national average approach : mitigation options and uncertainty reductions

    Science.gov (United States)

    Mendoza, D. L.; Gurney, K. R.

    2011-12-01

    The transportation sector is the second largest CO2 emitting economic sector in the United States, accounting for 32.3% of the total U.S. emissions in 2002. Within the transportation sector, the largest component (80%) is made up of onroad emissions. In order to accurately quantify future emissions and evaluate emissions regulation strategies, analysis must account for spatially-explicit fleet distribution, driving patterns, and mitigation strategies. Studies to date, however, have either focused on one of these three components, have been only completed at the national scale, or have not explicitly represented CO2 emissions instead relying on the use of vehicle miles traveled (VMT) as an emissions proxy. We compare a high resolution onroad emissions data product (Vulcan) to a national averaging of the Vulcan result. This comparison is performed in four groupings: light duty (LD) and heavy duty (HD) vehicle classes, and rural and urban road classes. Two different bias metrics are studied: 1) the state-specific, group-specific bias and 2) the same bias when weighted by the state share of the national group-specific emissions. In the first metric, we find a spread of positive and negative biases for the LD and HD vehicle groupings and these biases are driven by states having a greater/lesser proportion of LD/HD vehicles within their total state fleet than found from a national average. The standard deviation of these biases is 2.01% and 0.75% for the LD and HD groupings, respectively. These biases correlate with the road type present in a state, so that biases found in the urban and LD groups are both positive or both negative, with a similar relationship found between biases of the rural and HD groups. Additionally, the road group bias is driven by the distribution of VMT on individual road classes within the road groupings. When normalized by national totals, the state-level group-specific biases reflect states with large amounts of onroad travel that deviate

  7. Estimated Daily Average Per Capita Water Ingestion by Child and Adult Age Categories Based on USDA's 1994-96 and 1998 Continuing Survey of Food Intakes by Individuals (Journal Article)

    Science.gov (United States)

    Current water ingestion estimates are important for the assessment of risk to human populations of exposure to water-borne pollutants. This paper reports mean and percentile estimates of the distributions of daily average per capita water ingestion for 12 age range groups. The a...

  8. Determination of the fission-neutron averaged cross sections of some high-energy threshold reactions of interest for reactor dosimetry

    CERN Document Server

    Arribere, M A; Ribeiro-Guevara, S; Korochinsky, S; Blostein, J J

    2003-01-01

    For three high threshold reactions, we have measured the cross sections averaged over a sup 2 sup 3 sup 5 U fission neutron spectrum. The measured reactions, and corresponding averaged cross sections found, are: sup 1 sup 2 sup 7 I(n,2n) sup 1 sup 2 sup 6 I, (1.36+-0.12) mb; sup 9 sup 0 Zr(n,2n) sup 8 sup 9 sup m Zr, (13.86+-0.83) mu b; and sup 5 sup 8 Ni(n,d+np+pn) sup 5 sup 7 Co, (274+-15) mu b; all referred to the well known standard of (111+-3) mb for the sup 5 sup 8 Ni(n,p) sup 5 sup 8 sup m sup + sup g Co averaged cross section. The measured cross sections are of interest in nuclear engineering for the characterization of the fast neutron component in the energy distribution of reactor neutrons. (author)

  9. Development of laser diode-pumped high average power solid-state laser for the pumping of Ti:sapphire CPA system

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Yoichiro; Tei, Kazuyoku; Kato, Masaaki; Niwa, Yoshito; Harayama, Sayaka; Oba, Masaki; Matoba, Tohru; Arisawa, Takashi; Takuma, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    Laser diode pumped all solid state, high repetition frequency (PRF) and high energy Nd:YAG laser using zigzag slab crystals has been developed for the pumping source of Ti:sapphire CPA system. The pumping laser installs two main amplifiers which compose ring type amplifier configuration. The maximum amplification gain of the amplifier system is 140 and the condition of saturated amplification is achieved with this high gain. The average power of fundamental laser radiation is 250 W at the PRF of 200 Hz and the pulse duration is around 20 ns. The average power of second harmonic is 105 W at the PRF of 170 Hz and the pulse duration is about 16 ns. The beam profile of the second harmonic is near top hat and will be suitable for the pumping of Ti:sapphire laser crystal. The wall plug efficiency of the laser is 2.0 %. (author)

  10. Aging study of boiling water reactor high pressure injection systems

    Energy Technology Data Exchange (ETDEWEB)

    Conley, D.A.; Edson, J.L.; Fineman, C.F. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)

    1995-03-01

    The purpose of high pressure injection systems is to maintain an adequate coolant level in reactor pressure vessels, so that the fuel cladding temperature does not exceed 1,200{degrees}C (2,200{degrees}F), and to permit plant shutdown during a variety of design basis loss-of-coolant accidents. This report presents the results of a study on aging performed for high pressure injection systems of boiling water reactor plants in the United States. The purpose of the study was to identify and evaluate the effects of aging and the effectiveness of testing and maintenance in detecting and mitigating aging degradation. Guidelines from the United States Nuclear Regulatory Commission`s Nuclear Plant Aging Research Program were used in performing the aging study. Review and analysis of the failures reported in databases such as Nuclear Power Experience, Licensee Event Reports, and the Nuclear Plant Reliability Data System, along with plant-specific maintenance records databases, are included in this report to provide the information required to identify aging stressors, failure modes, and failure causes. Several probabilistic risk assessments were reviewed to identify risk-significant components in high pressure injection systems. Testing, maintenance, specific safety issues, and codes and standards are also discussed.

  11. The impact of including children with intellectual disability in general education classrooms on the academic achievement of their low-, average-, and high-achieving peers.

    Science.gov (United States)

    Sermier Dessemontet, Rachel; Bless, Gérard

    2013-03-01

    This study aimed at assessing the impact of including children with intellectual disability (ID) in general education classrooms with support on the academic achievement of their low-, average-, and high-achieving peers without disability. A quasi-experimental study was conducted with an experimental group of 202 pupils from classrooms with an included child with mild or moderate ID, and a control group of 202 pupils from classrooms with no included children with special educational needs (matched pairs sample). The progress of these 2 groups in their academic achievement was compared over a period of 1 school year. No significant difference was found in the progress of the low-, average-, or high-achieving pupils from classrooms with or without inclusion. The results suggest that including children with ID in primary general education classrooms with support does not have a negative impact on the progress of pupils without disability.

  12. Investigation on repetition rate and pulse duration influences on ablation efficiency of metals using a high average power Yb-doped ultrafast laser

    Directory of Open Access Journals (Sweden)

    Lopez J.

    2013-11-01

    Full Text Available Ultrafast lasers provide an outstanding processing quality but their main drawback is the low removal rate per pulse compared to longer pulses. This limitation could be overcome by increasing both average power and repetition rate. In this paper, we report on the influence of high repetition rate and pulse duration on both ablation efficiency and processing quality on metals. All trials have been performed with a single tunable ultrafast laser (350 fs to 10ps.

  13. Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Secondary Organic Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, Adam P.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

    2012-07-02

    The applicability of high resolution electrospray ionization mass spectrometry (HR ESI-MS) to measurements of the average oxygen to carbon ratio (O/C) in organic aerosols was investigated. Solutions with known average O/C containing up to 10 standard compounds representative of secondary organic aerosol (SOA) were analyzed and corresponding electrospray ionization efficiencies were quantified. The assumption of equal ionization efficiency commonly used in estimating O/C ratios of organic aerosols was found to be reasonably accurate. We found that the accuracy of the measured O/C ratios increases by averaging the values obtained from both (+) and (-) modes. A correlation was found between the ratio of the ionization efficiencies in the positive and negative ESI modes with the octanol-water partition constant, and more importantly, with the compound's O/C. To demonstrate the utility of this correlation for estimating average O/C values of unknown mixtures, we analyzed the ESI (+) and ESI (-) data for SOA produced by oxidation of limonene and isoprene and compared to online O/C measurements using an aerosol mass spectrometer (AMS). This work demonstrates that the accuracy of the HR ESI-MS methods is comparable to that of the AMS, with the added benefit of molecular identification of the aerosol constituents.

  14. Average stand age from forest inventory plots does not describe historical fire regimes in ponderosa pine and mixed-conifer forests of western North America

    Science.gov (United States)

    Jens T. Stevens; Hugh D. Safford; Malcolm P. North; Jeremy S. Fried; Andrew N. Gray; Peter M. Brown; Christopher R. Dolanc; Solomon Z. Dobrowski; Donald A. Falk; Calvin A. Farris; Jerry F. Franklin; Peter Z. Fulé; R. Keala Hagmann; Eric E. Knapp; Jay D. Miller; Douglas F. Smith; Thomas W. Swetnam; Alan H. Taylor; Julia A. Jones

    2016-01-01

    Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests...

  15. Development of a kilowatt-class, joule-level ultrafast laser for driving compact high average power coherent EUV/soft x-ray sources

    Science.gov (United States)

    Reagan, Brendan A.; Baumgarten, Cory M.; Pedicone, Michael A.; Bravo, Herman; Yin, Liang; Woolston, Mark; Wang, Hanchen; Menoni, Carmen S.; Rocca, Jorge J.

    2016-03-01

    Our recent progress in the development of high energy / high average power, chirped pulse amplification laser systems based on diode-pumped, cryogenically-cooled Yb:YAG amplifiers is discussed, including the demonstration of a laser that produces 1 Joule, sub-10 picosecond duration, λ = 1.03μm pulses at 500 Hz repetition rate. This compact, all-diodepumped laser combines a mode-locked Yb:KYW oscillator and a water-cooled Yb:YAG preamplifer with two cryogenic power amplification stages to produce 1.5 Joule pulses with high beam quality which are subsequently compressed. This laser system occupies an optical table area of less than 1.5x3m2. This laser was employed to pump plasma-based soft x-ray lasers at λ = 10-20nm at repetition rates >=100 Hz. To accomplish this, temporally-shaped pulses were focused at grazing incidence into a high aspect ratio line focus using cylindrical optics on a high shot capacity rotating metal target. This results in an elongated plasma amplifier that produces microjoule pulses at several narrow-linewidth EUV wavelengths between λ = 109Å and 189Å. The resulting fraction of a milliwatt average powers are the highest reported to date for a compact, coherent source operating at these wavelengths, to the best of our knowledge.

  16. Dynamo: a flexible, user-friendly development tool for subtomogram averaging of cryo-EM data in high-performance computing environments.

    Science.gov (United States)

    Castaño-Díez, Daniel; Kudryashev, Mikhail; Arheit, Marcel; Stahlberg, Henning

    2012-05-01

    Dynamo is a new software package for subtomogram averaging of cryo Electron Tomography (cryo-ET) data with three main goals: first, Dynamo allows user-transparent adaptation to a variety of high-performance computing platforms such as GPUs or CPU clusters. Second, Dynamo implements user-friendliness through GUI interfaces and scripting resources. Third, Dynamo offers user-flexibility through a plugin API. Besides the alignment and averaging procedures, Dynamo includes native tools for visualization and analysis of results and data, as well as support for third party visualization software, such as Chimera UCSF or EMAN2. As a demonstration of these functionalities, we studied bacterial flagellar motors and showed automatically detected classes with absent and present C-rings. Subtomogram averaging is a common task in current cryo-ET pipelines, which requires extensive computational resources and follows a well-established workflow. However, due to the data diversity, many existing packages offer slight variations of the same algorithm to improve results. One of the main purposes behind Dynamo is to provide explicit tools to allow the user the insertion of custom designed procedures - or plugins - to replace or complement the native algorithms in the different steps of the processing pipeline for subtomogram averaging without the burden of handling parallelization. Custom scripts that implement new approaches devised by the user are integrated into the Dynamo data management system, so that they can be controlled by the GUI or the scripting capacities. Dynamo executables do not require licenses for third party commercial software. Sources, executables and documentation are freely distributed on http://www.dynamo-em.org.

  17. Signal-to-noise ratio improvements in laser flow diagnostics using time-resolved image averaging and high dynamic range imaging

    Science.gov (United States)

    Giassi, Davide; Long, Marshall B.

    2016-08-01

    Two alternative image readout approaches are demonstrated to improve the signal-to-noise ratio (SNR) in temporally resolved laser-based imaging experiments of turbulent phenomena. The first method exploits the temporal decay characteristics of the phosphor screens of image intensifiers when coupled to an interline-transfer CCD camera operated in double-frame mode. Specifically, the light emitted by the phosphor screen, which has a finite decay constant, is equally distributed and recorded over the two sequential frames of the detector so that an averaged image can be reconstructed. The characterization of both detector and image intensifier showed that the technique preserves the correct quantitative information, and its applicability to reactive flows was verified using planar Rayleigh scattering and tested with the acquisition of images of both steady and turbulent partially premixed methane/air flames. The comparison between conventional Rayleigh results and the averaged ones showed that the SNR of the averaged image is higher than the conventional one; with the setup used in this work, the gain in SNR was seen to approach 30 %, for both the steady and turbulent cases. The second technique uses the two-frame readout of an interline-transfer CCD to increase the image SNR based on high dynamic range imaging, and it was tested in an unsteady non-reactive flow of Freon-12 injected in air. The result showed a 15 % increase in the SNR of the low-pixel-count regions of an image, when compared to the pixels of a conventionally averaged one.

  18. Performance of MgO:PPLN, KTA, and KNbO₃ for mid-wave infrared broadband parametric amplification at high average power.

    Science.gov (United States)

    Baudisch, M; Hemmer, M; Pires, H; Biegert, J

    2014-10-15

    The performance of potassium niobate (KNbO₃), MgO-doped periodically poled lithium niobate (MgO:PPLN), and potassium titanyl arsenate (KTA) were experimentally compared for broadband mid-wave infrared parametric amplification at a high repetition rate. The seed pulses, with an energy of 6.5 μJ, were amplified using 410 μJ pump energy at 1064 nm to a maximum pulse energy of 28.9 μJ at 3 μm wavelength and at a 160 kHz repetition rate in MgO:PPLN while supporting a transform limited duration of 73 fs. The high average powers of the interacting beams used in this study revealed average power-induced processes that limit the scaling of optical parametric amplification in MgO:PPLN; the pump peak intensity was limited to 3.8  GW/cm² due to nonpermanent beam reshaping, whereas in KNbO₃ an absorption-induced temperature gradient in the crystal led to permanent internal distortions in the crystal structure when operated above a pump peak intensity of 14.4  GW/cm².

  19. A highly detailed FEM volume conductor model based on the ICBM152 average head template for EEG source imaging and TCS targeting.

    Science.gov (United States)

    Haufe, Stefan; Huang, Yu; Parra, Lucas C

    2015-08-01

    In electroencephalographic (EEG) source imaging as well as in transcranial current stimulation (TCS), it is common to model the head using either three-shell boundary element (BEM) or more accurate finite element (FEM) volume conductor models. Since building FEMs is computationally demanding and labor intensive, they are often extensively reused as templates even for subjects with mismatching anatomies. BEMs can in principle be used to efficiently build individual volume conductor models; however, the limiting factor for such individualization are the high acquisition costs of structural magnetic resonance images. Here, we build a highly detailed (0.5mm(3) resolution, 6 tissue type segmentation, 231 electrodes) FEM based on the ICBM152 template, a nonlinear average of 152 adult human heads, which we call ICBM-NY. We show that, through more realistic electrical modeling, our model is similarly accurate as individual BEMs. Moreover, through using an unbiased population average, our model is also more accurate than FEMs built from mismatching individual anatomies. Our model is made available in Matlab format.

  20. Terbium gallium garnet ceramic-based Faraday isolator with compensation of thermally induced depolarization for high-energy pulsed lasers with kilowatt average power

    Science.gov (United States)

    Yasuhara, Ryo; Snetkov, Ilya; Starobor, Alexey; Palashov, Oleg

    2014-12-01

    A scalable aperture Faraday isolator for high-energy pulsed lasers with kW-level average power was demonstrated using terbium gallium garnet ceramics with water cooling and compensation of thermally induced depolarization in a magnetic field. An isolation ratio of 35 dB (depolarization ratio γ of 3.4 × 10-4) was experimentally observed at a maximum laser power of 740 W. By using this result, we estimated that this isolator maintains an isolation ratio of 30 dB for laser powers of up to 2.7 kW. Our results provide the solution for achieving optical isolation in high-energy (100 J to kJ) laser systems with a repetition rate greater than 10 Hz.

  1. Implementation of a reference-scaled average bioequivalence approach for highly variable generic drug products by the US Food and Drug Administration.

    Science.gov (United States)

    Davit, Barbara M; Chen, Mei-Ling; Conner, Dale P; Haidar, Sam H; Kim, Stephanie; Lee, Christina H; Lionberger, Robert A; Makhlouf, Fairouz T; Nwakama, Patrick E; Patel, Devvrat T; Schuirmann, Donald J; Yu, Lawrence X

    2012-12-01

    Highly variable (HV) drugs are defined as those for which within-subject variability (%CV) in bioequivalence (BE) measures is 30% or greater. Because of this high variability, studies designed to show whether generic HV drugs are bioequivalent to their corresponding HV reference drugs may need to enroll large numbers of subjects even when the products have no significant mean differences. To avoid unnecessary human testing, the US Food and Drug Administration's Office of Generic Drugs developed a reference-scaled average bioequivalence (RSABE) approach, whereby the BE acceptance limits are scaled to the variability of the reference product. For an acceptable RSABE study, an HV generic drug product must meet the scaled BE limit and a point estimate constraint. The approach has been implemented successfully. To date, the RSABE approach has supported four full approvals and one tentative approval of HV generic drug products.

  2. Residual thermal stress of a mounted KDP crystal after cooling and its effects on second harmonic generation of a high-average-power laser

    Science.gov (United States)

    Su, Ruifeng; Liu, Haitao; Liang, Yingchun; Yu, Fuli

    2017-01-01

    Thermal problems are huge challenges for solid state lasers that are interested in high output power, cooling of the nonlinear optics is insufficient to completely solve the problem of thermally induced stress, as residual thermal stress remains after cooling, which is first proposed, to the best of our knowledge. In this paper a comprehensive model incorporating principles of thermodynamics, mechanics and optics is proposed, and it is used to study the residual thermal stress of a mounted KDP crystal after cooling process from mechanical perspective, along with the effects of the residual thermal stress on the second harmonic generation (SHG) efficiency of a high-average-power laser. Effects of the structural parameters of the mounting configuration of the KDP crystal on the residual thermal stress are characterized, as well as the SHG efficiency. The numerical results demonstrate the feasibility of solving the problems of residual thermal stress from the perspective on structural design of mounting configuration.

  3. Are societies with a high value on the Active Ageing Index more age-integrated?

    NARCIS (Netherlands)

    P.A. Dykstra (Pearl); M. Fleischmann (Maria)

    2016-01-01

    textabstractCombining round four data from the European Social Survey (ESS) with indicators of Active Ageing, we examine conditions conducive to age integration. We use both a behavioural and an attitudinal measure of age integration: the prevalence of cross-age friendships and low levels of ageism.

  4. Arrange and average algorithm for the retrieval of aerosol parameters from multiwavelength high-spectral-resolution lidar/Raman lidar data.

    Science.gov (United States)

    Chemyakin, Eduard; Müller, Detlef; Burton, Sharon; Kolgotin, Alexei; Hostetler, Chris; Ferrare, Richard

    2014-11-01

    We present the results of a feasibility study in which a simple, automated, and unsupervised algorithm, which we call the arrange and average algorithm, is used to infer microphysical parameters (complex refractive index, effective radius, total number, surface area, and volume concentrations) of atmospheric aerosol particles. The algorithm uses backscatter coefficients at 355, 532, and 1064 nm and extinction coefficients at 355 and 532 nm as input information. Testing of the algorithm is based on synthetic optical data that are computed from prescribed monomodal particle size distributions and complex refractive indices that describe spherical, primarily fine mode pollution particles. We tested the performance of the algorithm for the "3 backscatter (β)+2 extinction (α)" configuration of a multiwavelength aerosol high-spectral-resolution lidar (HSRL) or Raman lidar. We investigated the degree to which the microphysical results retrieved by this algorithm depends on the number of input backscatter and extinction coefficients. For example, we tested "3β+1α," "2β+1α," and "3β" lidar configurations. This arrange and average algorithm can be used in two ways. First, it can be applied for quick data processing of experimental data acquired with lidar. Fast automated retrievals of microphysical particle properties are needed in view of the enormous amount of data that can be acquired by the NASA Langley Research Center's airborne "3β+2α" High-Spectral-Resolution Lidar (HSRL-2). It would prove useful for the growing number of ground-based multiwavelength lidar networks, and it would provide an option for analyzing the vast amount of optical data acquired with a future spaceborne multiwavelength lidar. The second potential application is to improve the microphysical particle characterization with our existing inversion algorithm that uses Tikhonov's inversion with regularization. This advanced algorithm has recently undergone development to allow automated and

  5. High strength hot rolled and aged microalloyed 5%Ni steel

    Directory of Open Access Journals (Sweden)

    A.K. Lis

    2006-08-01

    Full Text Available Purpose: Purpose of this paper was to give information about low temperature strength and impact CharpyVtoughness of low carbon microalloyed 5%Ni bainitic steel after thermomechanical rolling (TMR orthermomechanical controlled processing (TMCP and ageing at different temperatures: 580°C/2 h, 640°C/1hand 680°C/1h.Design/methodology/approach: The tensile strength tests were performed at -196, -60 and 20°C and Charpy Vsamples were broken at -100, -80, -60, -40, -20 and 20°C temperatures. The tensile strength TS, yield strengthYS, elongation A5 and reduction of area RA were established from tensile experiments. After TMCP 16 mm steelplate had YS = 730MPa, TS = 950 MPa, A5 = 22,5% and RA = 61% and impact energy > 50 J at -196°C.Findings: The best combination of mechanical properties; yield strength and Charpy V toughness was achieved forsteel after TMR and ageing 580°C/ 2h; YS = 800MPa, TS = 900 MPa, A5 = 22.5%, at -1000C KVmin.= 110 J.Research limitations/implications: The precise methodology for retained austenite identification and itsamount content determination in the investigated microstructures is still metallographic problem which needsto be resolved.Practical implications: The best combination of yield strength and Charpy V toughness was achieved for steelafter TMR and ageing 580°C/ 2h. At liquid nitrogen temperature ultrahigh strength properties were: YS = 1140MPa, TS = 1280 MPa, A5 = 26%, RA = 55% and KV 122 J at -100°C.Originality/value: The detailed microstructure examination of the steel with optical and mainly scanningtransmission electron microscopy was needed to explain its good properties at very low temperature. TRIP effectwas observed due to the presence of highly alloyed retained austenite in the microstructure. That type of steelmay be used for contemporary military and structural applications working at low temperatures.

  6. Plasma wakefields driven by an incoherent combination of laser pulses: a path towards high-average power laser-plasma accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Benedetti, C.; Schroeder, C.B.; Esarey, E.; Leemans, W.P.

    2014-05-01

    he wakefield generated in a plasma by incoherently combining a large number of low energy laser pulses (i.e.,without constraining the pulse phases) is studied analytically and by means of fully-self-consistent particle-in-cell simulations. The structure of the wakefield has been characterized and its amplitude compared with the amplitude of the wake generated by a single (coherent) laser pulse. We show that, in spite of the incoherent nature of the wakefield within the volume occupied by the laser pulses, behind this region the structure of the wakefield can be regular with an amplitude comparable or equal to that obtained from a single pulse with the same energy. Wake generation requires that the incoherent structure in the laser energy density produced by the combined pulses exists on a time scale short compared to the plasma period. Incoherent combination of multiple laser pulses may enable a technologically simpler path to high-repetition rate, high-average power laser-plasma accelerators and associated applications.

  7. Aggregation and Averaging.

    Science.gov (United States)

    Siegel, Irving H.

    The arithmetic processes of aggregation and averaging are basic to quantitative investigations of employment, unemployment, and related concepts. In explaining these concepts, this report stresses need for accuracy and consistency in measurements, and describes tools for analyzing alternative measures. (BH)

  8. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    1999-01-01

    In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...

  9. Mechanical Reproduction in an Age of High Art

    Directory of Open Access Journals (Sweden)

    Chris Barker

    2014-01-01

    Full Text Available This paper reopens the question of the place of high art in the period identified by Walter Benjamin as the age of mechanical reproduction. Walter Benjamin, Bruno Latour, and Adam Lowe are wrong to think that mechanical reproduction has transformed the concept of art, destroying the aura of art or transmitting that aura from original to copy. The concept of art cannot be redefined by the modern change in the capacity to reproduce art unless art was initially defined primarily by its uniqueness/nonreproducibility. Photographic reproduction has caused major changes in the visual arts and in the way we consume art, but reproductive techniques have a long, continuous history that includes the production and reproduction of exact, artistic copies.

  10. Aging of organic materials around high-energy particle accelerators

    Science.gov (United States)

    Tavlet, Marc

    1997-08-01

    Around particle accelerators used for fundamental research on the basic structure of matter, materials and components are exposed to ionizing radiation caused by beam losses in the proton machines and by synchrotron radiation in the lepton machines. Furthermore, with the high-energy and high-intensity collisions produced from future colliders, radiation damage is also to be expected in particle-physics detectors. Therefore, for a safe and reliable operation, the radiation aging of most of the components has to be assessed prior to their selection. An extensive radiation-damage test program has been carried out at CERN for decades on a routine basis and many results have been published. The tests have mainly concentrated on magnet-coil insulations and cable-insulating materials; they are carried out in accordance with the IEC 544 standard which defines the mechanical tests to be performed and the methods of degradation evaluation. The mechanical tests are also used to assess the degradation of composite structural materials. Moreover, electrical properties of high-voltage insulations and optical properties of organic scintillators and wave guides have also been studied. Our long-term experience has pointed out many parameters to be taken into account for the estimate of the lifetime of components in the radiation environment of our accelerators. One of the main parameters is the dose-rate effect, but the influence of other parameters has sometimes to be taken into account.

  11. Reynolds-averaged Navier-Stokes investigation of high-lift low-pressure turbine blade aerodynamics at low Reynolds number

    Science.gov (United States)

    Arko, Bryan M.

    Design trends for the low-pressure turbine (LPT) section of modern gas turbine engines include increasing the loading per airfoil, which promises a decreased airfoil count resulting in reduced manufacturing and operating costs. Accurate Reynolds-Averaged Navier-Stokes predictions of separated boundary layers and transition to turbulence are needed, as the lack of an economical and reliable computational model has contributed to this high-lift concept not reaching its full potential. Presented here for what is believed to be the first time applied to low-Re computations of high-lift linear cascade simulations is the Abe-Kondoh-Nagano (AKN) linear low-Re two-equation turbulence model which utilizes the Kolmogorov velocity scale for improved predictions of separated boundary layers. A second turbulence model investigated is the Kato-Launder modified version of the AKN, denoted MPAKN, which damps turbulent production in highly strained regions of flow. Fully Laminar solutions have also been calculated in an effort to elucidate the transitional quality of the turbulence model solutions. Time accurate simulations of three modern high-lift blades at a Reynolds number of 25,000 are compared to experimental data and higher-order computations in order to judge the accuracy of the results, where it is shown that the RANS simulations with highly refined grids can produce both quantitatively and qualitatively similar separation behavior as found in experiments. In particular, the MPAKN model is shown to predict the correct boundary layer behavior for all three blades, and evidence of transition is found through inspection of the components of the Reynolds Stress Tensor, spectral analysis, and the turbulence production parameter. Unfortunately, definitively stating that transition is occurring becomes an uncertain task, as similar evidence of the transition process is found in the Laminar predictions. This reveals that boundary layer reattachment may be a result of laminar

  12. Optimization of X-ray sources from a high-average-power ND:Glass laser-produced plasma for proximity lithography

    Energy Technology Data Exchange (ETDEWEB)

    Celliers, P.; Da Silva, L.B.; Dane, C.B. [and others

    1996-06-01

    The concept of a laser-based proximity lithography system for electronic microcircuit production has advanced to the point where a detailed design of a prototype system capable of exposing wafers at 40 wafer levels per hr is technically feasible with high-average-power laser technology. In proximity x-ray lithography, a photoresist composed of polymethyl- methacrylate (PMMA) or similar material is exposed to x rays transmitted through a mask placed near the photoresist, a procedure which is similar to making a photographic contact print. The mask contains a pattern of opaque metal features, with line widths as small as 0.12 {mu}m, placed on a thin (1-{mu}m thick) Si membrane. During the exposure, the shadow of the mask projected onto the resist produces in the physical and chemical properties of the resist a pattern of variation with the same size and shape as the features contained in the metal mask. This pattern can be further processed to produce microscopic structures in the Si substrate. The main application envisioned for this technology is the production of electronic microcircuits with spatial features significantly smaller than currently achievable with conventional optical lithographic techniques (0.12 {micro}m vs 0.25 {micro}m). This article describes work on optimizing a laser-produced plasma x-ray source intended for microcircuit production by proximity lithography.

  13. Optimization of x-ray sources for proximity lithography produced by a high average power Nd:glass laser{sup a}

    Energy Technology Data Exchange (ETDEWEB)

    Celliers, P.; Da Silva, L.B.; Dane, C.B.; Mrowka, S.; Norton, M.; Harder, J.; Hackel, L.; Matthews, D.L. [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States); Fiedorowicz, H.; Bartnik, A. [Laser Plasma Interaction Section, Military University of Technology, Institute of Optoelectronics, 01-489 Warsaw 49 (Poland); Maldonado, J.R. [IBM Microelectronics, Hopewell Junction, New York 12533 (United States); Abate, J.A. [AT& T Bell Laboratories, Murray Hill, New Jersey 07974 (United States)

    1996-06-01

    We measured the conversion efficiency of laser pulse energy into keV x rays from a variety of solid planar targets and a Xe gas puff target irradiated using a high average power Nd:glass slab laser capable of delivering 13 ns full width at half-maximum pulses at up to 20 J at 1.053 {mu}m and 12 J at 0.53 {mu}m. Targets were chosen to optimize emission in the 10{endash}15 A wavelength band, including {ital L}-shell emission from materials with atomic numbers in the range {ital Z}=24{endash}30 and {ital M}-shell emission from Xe ({ital Z}=54). With 1.053 {mu}m a maximum conversion of 11{percent} into 2{pi} sr was measured from solid Xe targets. At 0.527 {mu}m efficiencies of 12{percent}{endash}18{percent}/(2{pi} sr) were measured for all of the solid targets in the same wavelength band. The x-ray conversion efficiency from the Xe gas puff target was considerably lower, at about 3{percent}/(2{pi} sr) when irradiated with 1.053 {mu}m. {copyright} {ital 1996 American Institute of Physics.}

  14. The effect of an aerobic training program on the electrical remodeling of the heart: high-frequency components of the signal-averaged electrocardiogram are predictors of the maximal aerobic power

    Directory of Open Access Journals (Sweden)

    M. Marocolo

    2007-02-01

    Full Text Available Increased heart rate variability (HRV and high-frequency content of the terminal region of the ventricular activation of signal-averaged ECG (SAECG have been reported in athletes. The present study investigates HRV and SAECG parameters as predictors of maximal aerobic power (VO2max in athletes. HRV, SAECG and VO2max were determined in 18 high-performance long-distance (25 ± 6 years; 17 males runners 24 h after a training session. Clinical visits, ECG and VO2max determination were scheduled for all athletes during thew training period. A group of 18 untrained healthy volunteers matched for age, gender, and body surface area was included as controls. SAECG was acquired in the resting supine position for 15 min and processed to extract average RR interval (Mean-RR and root mean squared standard deviation (RMSSD of the difference of two consecutive normal RR intervals. SAECG variables analyzed in the vector magnitude with 40-250 Hz band-pass bi-directional filtering were: total and 40-µV terminal (LAS40 duration of ventricular activation, RMS voltage of total (RMST and of the 40-ms terminal region of ventricular activation. Linear and multivariate stepwise logistic regressions oriented by inter-group comparisons were adjusted in significant variables in order to predict VO2max, with a P < 0.05 considered to be significant. VO2max correlated significantly (P < 0.05 with RMST (r = 0.77, Mean-RR (r = 0.62, RMSSD (r = 0.47, and LAS40 (r = -0.39. RMST was the independent predictor of VO2max. In athletes, HRV and high-frequency components of the SAECG correlate with VO2max and the high-frequency content of SAECG is an independent predictor of VO2max.

  15. Your Average Nigga

    Science.gov (United States)

    Young, Vershawn Ashanti

    2004-01-01

    "Your Average Nigga" contends that just as exaggerating the differences between black and white language leaves some black speakers, especially those from the ghetto, at an impasse, so exaggerating and reifying the differences between the races leaves blacks in the impossible position of either having to try to be white or forever struggling to…

  16. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    2001-01-01

    In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...

  17. OH-initiated heterogeneous aging of highly oxidized organic aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, Sean H.; Nah, Theodora; Daumit, Kelly E.; Smith, Jared D.; Leone, Stephen R.; Kolb, Charles E.; Worsnop, Douglas R.; Wilson, Kevin R.; Kroll, Jesse H.

    2011-12-05

    The oxidative evolution (“aging”) of organic species in the atmosphere is thought to have a major influence on the composition and properties of organic particulate matter, but remains poorly understood, particularly for the most oxidized fraction of the aerosol. Here we measure the kinetics and products of the heterogeneous oxidation of highly oxidized organic aerosol, with an aim of better constraining such atmospheric aging processes. Submicron particles composed of model oxidized organics—1,2,3,4-butanetetracarboxylic acid (C{sub 8}H{sub 10}O{sub 8}), citric acid (C{sub 6}H{sub 8}O{sub 7}), tartaric acid (C{sub 4}H{sub 6}O{sub 6}), and Suwannee River fulvic acid—were oxidized by gas-phase OH in a flow reactor, and the masses and elemental composition of the particles were monitored as a function of OH exposure. In contrast to our previous studies of less-oxidized model systems (squalane, erythritol, and levoglucosan), particle mass did not decrease significantly with heterogeneous oxidation. Carbon content of the aerosol always decreased somewhat, but this mass loss was approximately balanced by an increase in oxygen content. The estimated reactive uptake coefficients of the reactions range from 0.37 to 0.51 and indicate that such transformations occur at rates corresponding to 1-2 weeks in the atmosphere, suggesting their importance in the atmospheric lifecycle of organic particulate matter.

  18. Patent Strategy at the Age of High Technology

    Science.gov (United States)

    Aoyama, Hirokazu

    This paper is a summary of the lecture which the author presented at the 5th Hokuriku Workshop for Study of Scientific and Technological Information Activities on the 17th of January in 1986. The author analyzed the present situation and made some suggestions on them ; (1) the role of patent system has shifted from introduction of foreign technologies to independent technological development at the age of high technology, (2) circumstances of rapidly increasing international patent war, particularly patent conflict between U.S. and Japan concerning U.S. ITC, (3) as the service of soft aspects of economy has been closed up, the new business has come to the fore front, and the move to consider technology as a good has been activated, (4) how patent specification should be written, the way of obtaining and protecting patent successfully, (5) basic pattern of patent strategy and what the strategy should be to respond to the enterprises level, (6) present situation of patent information service, effective use of patent maps and information strategy.

  19. Short communication: Variation of total immunoglobulin G and β-lactoglobulin concentrations in colostrum and milk from Canadian Holsteins classified as high, average, or low immune responders.

    Science.gov (United States)

    Fleming, K; Thompson-Crispi, K A; Hodgins, D C; Miglior, F; Corredig, M; Mallard, B A

    2016-03-01

    The objective of this study was to evaluate IgG and β-lactoglobulin (β-LG) concentrations in colostrum and milk of Canadian Holsteins (n=108) classified as high (H), average (A), or low (L) for antibody-mediated (AMIR) or cell-mediated immune responses (CMIR) based on estimated breeding values. It was hypothesized that H-AMIR and H-CMIR cows produce colostrum (first milking) and milk (d 5 postcalving) with higher concentrations of IgG and β-LG. Data for IgG and β-LG in colostrum and milk were analyzed independently using mixed linear models. Least squares means were compared using Tukey's test. Cows classified as H-AMIR had higher IgG and β-LG concentrations in colostrum compared with A- and L-AMIR cows; 84% of H-AMIR, 69% of A-AMIR, and 68% of L-AMIR cows had over 5,000 mg/dL IgG in colostrum. No differences in IgG and β-LG concentrations in colostrum were noted among cows ranked on CMIR or in milk of cows ranked on AMIR. β-Lactoglobulin and IgG concentrations were positively correlated in colostrum. Breeding cows for H-AMIR status may reduce failure of passive transfer of IgG in their calves; β-LG may play a role in bovine immune defenses. Colostrum from H-AMIR cows may serve as a more economical feedstock source for manufacturing natural health products.

  20. High Satisfaction and Return to Sports After Total Shoulder Arthroplasty in Patients Aged 55 Years and Younger.

    Science.gov (United States)

    Garcia, Grant H; Liu, Joseph N; Sinatro, Alec; Wu, Hao-Hua; Dines, Joshua S; Warren, Russell F; Dines, David M; Gulotta, Lawrence V

    2017-06-01

    Young, active candidates for total shoulder arthroplasty (TSA) are a unique group of patients. Not only do they demand longevity and improved function, but they also desire a return to physical activities. To determine the rate of return to sports in patients aged ≤55 years undergoing TSA. Case series; Level of evidence, 4. This was a retrospective review of consecutive patients who underwent anatomic TSA at a single institution. Exclusion criteria included age at the time of surgery >55 years and 55 years). The average VAS score improved from 5.6 to 0.9 ( P 55/57) restarted at least 1 sport at an average of 6.7 months. Direct rates of return were as follows: fitness sports (97.2%), golf (93.3%), singles tennis (87.5%), swimming (77.7%), basketball (75.0%), and flag football (66.7%). Patients in 47 shoulders (82.4%) returned to a similar or higher level of sports; 90.3% returned to high-demand sports, and 83.8% returned to high upper extremity sports. There was no significant difference in rates of return to sports by body mass index, sex, age, preoperative diagnosis, revision status, and dominant extremity. In patients aged ≤55 years undergoing TSA, there was a 96.4% rate of return to ≥1 previous sports at an average of 6.7 months. Furthermore, at an average follow-up of 61.0 months, no patients needed revision of their glenoid component, despite an 83.8% rate of return to high upper extremity sports. While caution should still be advised in young, active patients undergoing TSA, these results demonstrate a high satisfaction rate and improved ability to return to most sports after surgery.

  1. DNA methylation-based age prediction from saliva: High age predictability by combination of 7 CpG markers.

    Science.gov (United States)

    Hong, Sae Rom; Jung, Sang-Eun; Lee, Eun Hee; Shin, Kyoung-Jin; Yang, Woo Ick; Lee, Hwan Young

    2017-07-01

    DNA methylation is currently one of the most promising age-predictive biomarkers. Many studies have reported DNA methylation-based age predictive models, but most of these are based on DNA methylation patterns from blood. Only a few studies have examined age-predictive DNA patterns in saliva, which is one of the most frequently-encountered body fluids at crime scenes. In this study, we generated genome-wide DNA methylation profiles of saliva from 54 individuals and identified CpG markers that showed a high correlation between methylation and age. Because the age-associated marker candidates from saliva differed from those of blood, we investigated DNA methylation patterns of 6 age-associated CpG marker candidates (cg00481951, cg19671120, cg14361627, cg08928145, cg12757011, and cg07547549 of the SST, CNGA3, KLF14, TSSK6, TBR1, and SLC12A5 genes, respectively) in addition to a cell type-specific CpG marker (cg18384097 of the PTPN7 gene) in an independent set of saliva samples obtained from 226 individuals aged 18 to 65 years. Multiplex methylation SNaPshot reactions were used to generate the data. We then generated a linear regression model with age information and the methylation profile from the 113 training samples. The model exhibited a 94.5% correlation between predicted and chronological age with a mean absolute deviation (MAD) from chronological age of 3.13 years. In subsequent validation using 113 test samples, we also observed a high correlation between predicted and chronological age (Spearman's rho=0.952, MAD from chronological age=3.15years). The model composed of 7 selected CpG sites enabled age prediction in saliva with high accuracy, which will be useful in saliva analysis for investigative leads. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Covariant approximation averaging

    CERN Document Server

    Shintani, Eigo; Blum, Thomas; Izubuchi, Taku; Jung, Chulwoo; Lehner, Christoph

    2014-01-01

    We present a new class of statistical error reduction techniques for Monte-Carlo simulations. Using covariant symmetries, we show that correlation functions can be constructed from inexpensive approximations without introducing any systematic bias in the final result. We introduce a new class of covariant approximation averaging techniques, known as all-mode averaging (AMA), in which the approximation takes account of contributions of all eigenmodes through the inverse of the Dirac operator computed from the conjugate gradient method with a relaxed stopping condition. In this paper we compare the performance and computational cost of our new method with traditional methods using correlation functions and masses of the pion, nucleon, and vector meson in $N_f=2+1$ lattice QCD using domain-wall fermions. This comparison indicates that AMA significantly reduces statistical errors in Monte-Carlo calculations over conventional methods for the same cost.

  3. CT coronary angiography is feasible for the assessment of coronary artery disease in chronic dialysis patients, despite high average calcium scores.

    Directory of Open Access Journals (Sweden)

    Mihály K de Bie

    Full Text Available PURPOSE: Significant obstructive coronary artery disease (CAD is common in asymptomatic dialysis patients. Identifying these high risk patients is warranted and may improve the prognosis of this vulnerable patient group. Routine catheterization of incident dialysis patients has been proposed, but is considered too invasive. CT-angiography may therefore be more appropriate. However, extensive coronary calcification, often present in this patient group, might hamper adequate lumen evaluation. The objective of this study was to assess the feasibility of CT-angiography in this patient group. METHODS: For this analysis all patients currently participating in the ICD2 trial (ISRCTN20479861, with no history of PCI or CABG were included. The major epicardial vessels were evaluated on a segment basis (segment 1-3, 5-8, 11 and 13 by a team consisting of an interventional and an imaging specialist. Segments were scored as not significant, significant and not interpretable. RESULTS: A total of 70 dialysis patients, with a mean age of 66±8 yrs and predominantly male (70% were included. The median calcium score was 623 [79, 1619]. Over 90% of the analyzed segments were considered interpretable. The incidence of significant CAD on CT was 43% and was associated with cardiovascular events during follow-up. The incidence of cardiovascular events after 2-years follow-up: 36% vs. 0% in patients with no significant CAD (p<0.01. CONCLUSION: Despite the high calcium scores CT-angiography is feasible for the evaluation of the extent of CAD in dialysis patients. Moreover the presence of significant CAD on CT was associated with events during follow-up.

  4. Predicting Long-Term College Success through Degree Completion Using ACT[R] Composite Score, ACT Benchmarks, and High School Grade Point Average. ACT Research Report Series, 2012 (5)

    Science.gov (United States)

    Radunzel, Justine; Noble, Julie

    2012-01-01

    This study compared the effectiveness of ACT[R] Composite score and high school grade point average (HSGPA) for predicting long-term college success. Outcomes included annual progress towards a degree (based on cumulative credit-bearing hours earned), degree completion, and cumulative grade point average (GPA) at 150% of normal time to degree…

  5. High average daily intake of PCDD/Fs and serum levels in residents living near a deserted factory producing pentachlorophenol (PCP) in Taiwan: influence of contaminated fish consumption

    Energy Technology Data Exchange (ETDEWEB)

    Lee Ching-Chang; Lin Wu-Ting; Liao Po-Chi; Su Huey-Jen [Dept. of Environmental and Occupational Health/Research Center of Environmental Trace Toxic substances, Medical Coll., National Cheng Kung Univ., Tainan (Taiwan); Chen Hsiu-Lin [Inst. of Basic Medical Sciences, Medical Coll., National Cheng Kung Univ., Tainan (Taiwan)

    2004-09-15

    Many reports have suggested that PCDD/Fs (polychlorinated dibenzo-p-dioxins and dibenzofurans) contribute to immune deficiency, liver damage, human carcinogenesis, and neuromotor maturation in children. Therefore, beginning in 1999, the Taiwan Environmental Protection Agency (EPA) conducted a survey to determine serum levels of PCDD/Fs in the general populations living around 19 incinerators in Taiwan. Relatively high average serum PCDD/F levels were unexpectedly found in Tainan city, a less industrialized area in southwestern Taiwan, than in other urban areas. We therefore reviewed the usage history of the land and found that a factory situated between Hsien-Gong Li and Lu-Erh Li, two administrative units of Tainan city, had been manufacturing pentachlorophenol (PCP) between 1967 and 1982. PCDD/Fs are formed as byproducts in the PCP manufacturing process. Exposure to PCP and its derivatives via the food chain is the most significant intake route of PCDD/Fs in consumers in the European Union (EU). In Japan, in addition to combustion processes, PCP and chlornitrofen (CNP) have also been identified as the major sources of PCDD/Fs in Tokyo Bay7. A preliminary investigation showed that the soil in the PCP factory and sediments in the sea reservoir (13 hectares) near the deserted factory were seriously contaminated with PCDD/Fs (260-184,000 and 20-6220 pg I-TEQ/g, respectively), levels higher than those in other countries. Therefore, the aim of this study was to compare the PCDD/F levels of fish meat in the sea reservoir and the serum in inhabitants living in the vicinity of the closed PCP plant and other nearby areas. The data from human and other biota samples might clarify the transmission pathway of the PCDD/F contaminants from the PCP factory to local residents, provide information about the exposure status of those living in the vicinity of the deserted PCP factory, and also lead to useful suggestions for controlling PCDD/F accumulation in those living near such

  6. High-average power THG of a diode-pumped Nd:YAG laser at 355 nm generated by LiB3O5 crystal

    Institute of Scientific and Technical Information of China (English)

    Yong Bi(毕勇); Yan Feng(冯衍); Huarong Gong(巩华荣); Hongbo Zhang(张鸿博); Zuyan Xu(许祖彦)

    2003-01-01

    More than 6 W average power ultraviolet radiation at 355 nm was generated in LiB3O5 (LBO) crystalthrough the frequency mixing of the fundamental and second harmonic radiation of a Nd:YAG laser. Thisperformance was achieved with 38% optical-to-optical conversion efficiency (532 nm to 355 nm).

  7. Negative Average Preference Utilitarianism

    Directory of Open Access Journals (Sweden)

    Roger Chao

    2012-03-01

    Full Text Available For many philosophers working in the area of Population Ethics, it seems that either they have to confront the Repugnant Conclusion (where they are forced to the conclusion of creating massive amounts of lives barely worth living, or they have to confront the Non-Identity Problem (where no one is seemingly harmed as their existence is dependent on the “harmful” event that took place. To them it seems there is no escape, they either have to face one problem or the other. However, there is a way around this, allowing us to escape the Repugnant Conclusion, by using what I will call Negative Average Preference Utilitarianism (NAPU – which though similar to anti-frustrationism, has some important differences in practice. Current “positive” forms of utilitarianism have struggled to deal with the Repugnant Conclusion, as their theory actually entails this conclusion; however, it seems that a form of Negative Average Preference Utilitarianism (NAPU easily escapes this dilemma (it never even arises within it.

  8. Dephosphorization mechanism of prolonged sludge age SBBR treating saline and high-phosphorus wastewater

    Institute of Scientific and Technical Information of China (English)

    龙腾锐; 陈垚; 周健

    2009-01-01

    Prolonged sludge age sequencing batch biofilm reactor (SBBR) without sludge discharge appears high performance phosphorus removal in treating saline and high-phosphorus wastewater,which cannot be explained by traditional biological dephosphorization theory. The new path and mechanism of phosphorus removal was discussed on the phosphorus balance of phosphorus removal system without sludge discharge. Phosphorus balance in sludge was studied on 26 running cycles of the phosphorus reduction system. The results show that there is only 0.12 mg/g poly-P in sludge at the end of each reaction period,not phosphorus uptake by polyphosphate-accumulating organisms (PAOs). It is found that 41.8 mg/L of external phosphorus gets lost per day averagely,and 155 mg of internal phosphorus in sludge gets lost. The matrix bound phosphine in sludge achieves 36.04 mg/kg measured by alkaline digestion,and there is 18.44 mg/kg in +1 valence state,a intermediate,in sludge. This implies that the phosphorus removal system of prolonged sludge age SBBR without sludge discharge is a phosphate reduction,and the path of dephosphorization is phosphate→hypophosphite→phosphine.

  9. Correlation between high-risk pregnancy and developmental delay in children aged 4–60 months

    Directory of Open Access Journals (Sweden)

    Saba Amiri

    2012-09-01

    Full Text Available Background: The future development of children is considered more than ever now due to the advances in medical knowledge and thus the increase in survival rates of high-risk infants. This study investigated the correlation between high-risk pregnancy and developmental delay in children aged 4–60 months. Methods: This descriptive study was conducted on 401 mothers and their children (4–60 months who visited health service centers affiliated to Isfahan University of Medical Sciences, Iran, in 2011. Sampling was carried out in several stages, and the Ages and Stage Questionnaire was completed by the participants. Data were analyzed with SPSS 18 software and independent t-test; Mann-Whitney and logistic-regression tests were used. Results: The average age of children in the low-risk pregnancy group was 22±16 months, and that in the high-risk pregnancy group was 18.9±14.8 months. The majority of children were female (53.1%. The prevalence of high-risk pregnancies was 80.5%, and the prevalence of developmental delay was 18.7%. Multiple pregnancies, low birth weight, habitual abortions, maternal medical disorders in pregnancy, and gestational diabetes had significant correlations with developmental delay in children (P<0.04. In the logistic model, male gender, low birth weight, family marriage, and maternal medical disorders during pregnancy showed significant correlations with developmental delay in children (P<0.05. Additionally, abnormal body mass index (BMI and social and economic status showed probability values close to the significance level (P = 0.05, whereas other high-risk pregnancy variables had no correlation with developmental delay in children. A correlation between high-risk pregnancy and developmental delay (P = 0.002 and fine motor delay was observed (P = 0.02, but no correlation was observed between high-risk pregnancy and other developmental domains. Conclusion: This study showed that some high-risk pregnancy variables had a

  10. Vertical Gradients in Water Chemistry and Age in the Northern High Plains Aquifer, Nebraska, 2003

    Science.gov (United States)

    McMahon, P.B.; Böhlke, J.K.; Carney, C.P.

    2007-01-01

    The northern High Plains aquifer is the primary source of water used for domestic, industrial, and irrigation purposes in parts of Colorado, Kansas, Nebraska, South Dakota, and Wyoming. Despite the aquifer's importance to the regional economy, fundamental ground-water characteristics, such as vertical gradients in water chemistry and age, remain poorly defined. As part of the U.S. Geological Survey's National Water-Quality Assessment Program, water samples from nested, short-screen monitoring wells installed in the northern High Plains aquifer were analyzed for major ions, nutrients, trace elements, dissolved organic carbon, pesticides, stable and radioactive isotopes, dissolved gases, and other parameters to evaluate vertical gradients in water chemistry and age in the aquifer. Chemical data and tritium and radiocarbon ages show that water in the aquifer was chemically and temporally stratified in the study area, with a relatively thin zone of recently recharged water (less than 50 years) near the water table overlying a thicker zone of older water (1,800 to 15,600 radiocarbon years). In areas where irrigated agriculture was an important land use, the recently recharged ground water was characterized by elevated concentrations of major ions and nitrate and the detection of pesticide compounds. Below the zone of agricultural influence, major-ion concentrations exhibited small increases with depth and distance along flow paths because of rock/water interactions. The concentration increases were accounted for primarily by dissolved calcium, sodium, bicarbonate, sulfate, and silica. In general, the chemistry of ground water throughout the aquifer was of high quality. None of the approximately 90 chemical constituents analyzed in each sample exceeded primary drinking-water standards. Mass-balance models indicate that changes in ground-water chemistry along flow paths in the aquifer can be accounted for by small amounts of feldspar and calcite dissolution; goethite and

  11. ZPR-3 Assembly 6F : A spherical assembly of highly enriched uranium, depleted uranium, aluminum and steel with an average {sup 235}U enrichment of 47 atom %.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; McKnight, R. D; Schaefer, R. W.; Nuclear Engineering Division

    2010-09-30

    Assembly 6F (ZPR-3/6F), the final phase of the Assembly 6 program, simulated a spherical core with a thick depleted uranium reflector. ZPR-3/6F was designed as a fast reactor physics benchmark experiment with an average core {sup 235}U enrichment of approximately 47 at.%. Approximately 81.4% of the total fissions in this assembly occur above 100 keV, approximately 18.6% occur below 100 keV, and essentially none below 0.625 eV - thus the classification as a 'fast' assembly. This assembly is Fast Reactor Benchmark No. 7 in the Cross Section Evaluation Working Group (CSEWG) Benchmark Specifications and has historically been used as a data validation benchmark assembly. Loading of ZPR-3/6F began in late December 1956, and the experimental measurements were performed in January 1957. The core consisted of highly enriched uranium (HEU) plates, depleted uranium plates, perforated aluminum plates and stainless steel plates loaded into aluminum drawers, which were inserted into the central square stainless steel tubes of a 31 x 31 matrix on a split table machine. The core unit cell consisted of three columns of 0.125 in.-wide (3.175 mm) HEU plates, three columns of 0.125 in.-wide depleted uranium plates, nine columns of 0.125 in.-wide perforated aluminum plates and one column of stainless steel plates. The maximum length of each column of core material in a drawer was 9 in. (228.6 mm). Because of the goal to produce an approximately spherical core, core fuel and diluent column lengths generally varied between adjacent drawers and frequently within an individual drawer. The axial reflector consisted of depleted uranium plates and blocks loaded in the available space in the front (core) drawers, with the remainder loaded into back drawers behind the front drawers. The radial reflector consisted of blocks of depleted uranium loaded directly into the matrix tubes. The assembly geometry approximated a reflected sphere as closely as the square matrix tubes, the drawers and the

  12. Personalised Prescription of Scalable High Intensity Interval Training to Inactive Female Adults of Different Ages

    Science.gov (United States)

    Mair, Jacqueline L.

    2016-01-01

    Stepping is a convenient form of scalable high-intensity interval training (HIIT) that may lead to health benefits. However, the accurate personalised prescription of stepping is hampered by a lack of evidence on optimal stepping cadences and step heights for various populations. This study examined the acute physiological responses to stepping exercise at various heights and cadences in young (n = 14) and middle-aged (n = 14) females in order to develop an equation that facilitates prescription of stepping at targeted intensities. Participants completed a step test protocol consisting of randomised three-minute bouts at different step cadences (80, 90, 100, 110 steps·min-1) and step heights (17, 25, 30, 34 cm). Aerobic demand and heart rate values were measured throughout. Resting metabolic rate was measured in order to develop female specific metabolic equivalents (METs) for stepping. Results revealed significant differences between age groups for METs and heart rate reserve, and within-group differences for METs, heart rate, and metabolic cost, at different step heights and cadences. At a given step height and cadence, middle-aged females were required to work at an intensity on average 1.9 ± 0.26 METs greater than the younger females. A prescriptive equation was developed to assess energy cost in METs using multilevel regression analysis with factors of step height, step cadence and age. Considering recent evidence supporting accumulated bouts of HIIT exercise for health benefits, this equation, which allows HIIT to be personally prescribed to inactive and sedentary women, has potential impact as a public health exercise prescription tool. PMID:26848956

  13. Personalised Prescription of Scalable High Intensity Interval Training to Inactive Female Adults of Different Ages.

    Directory of Open Access Journals (Sweden)

    Jacqueline L Mair

    Full Text Available Stepping is a convenient form of scalable high-intensity interval training (HIIT that may lead to health benefits. However, the accurate personalised prescription of stepping is hampered by a lack of evidence on optimal stepping cadences and step heights for various populations. This study examined the acute physiological responses to stepping exercise at various heights and cadences in young (n = 14 and middle-aged (n = 14 females in order to develop an equation that facilitates prescription of stepping at targeted intensities. Participants completed a step test protocol consisting of randomised three-minute bouts at different step cadences (80, 90, 100, 110 steps·min-1 and step heights (17, 25, 30, 34 cm. Aerobic demand and heart rate values were measured throughout. Resting metabolic rate was measured in order to develop female specific metabolic equivalents (METs for stepping. Results revealed significant differences between age groups for METs and heart rate reserve, and within-group differences for METs, heart rate, and metabolic cost, at different step heights and cadences. At a given step height and cadence, middle-aged females were required to work at an intensity on average 1.9 ± 0.26 METs greater than the younger females. A prescriptive equation was developed to assess energy cost in METs using multilevel regression analysis with factors of step height, step cadence and age. Considering recent evidence supporting accumulated bouts of HIIT exercise for health benefits, this equation, which allows HIIT to be personally prescribed to inactive and sedentary women, has potential impact as a public health exercise prescription tool.

  14. Aging, tumor suppression and cancer: High-wire act!

    Energy Technology Data Exchange (ETDEWEB)

    Campisi, Judith

    2004-08-15

    Evolutionary theory holds that aging is a consequence of the declining force of natural selection with age. We discuss here the evidence that among the causes of aging in complex multicellular organisms, such as mammals, is the antagonistically pleiotropic effects of the cellular responses that protect the organism from cancer. Cancer is relatively rare in young mammals, owing in large measure to the activity of tumor suppressor mechanisms. These mechanisms either protect the genome from damage and/or mutations, or they elicit cellular responses--apoptosis or senescence--that eliminate or prevent the proliferation of somatic cells at risk for neoplastic transformation.We focus here on the senescence response, reviewing its causes, regulation and effects. In addition, we describe recent data that support the idea that both senescence and apoptosis may indeed be the double-edged swords predicted by the evolutionary hypothesis of antagonistic pleiotropy--protecting organisms from cancer early in life, but promoting aging phenotypes, including late life cancer, in older organisms.

  15. Disentangling High Fat, Low Carb, and Healthy Aging.

    Science.gov (United States)

    Brown-Borg, Holly M

    2017-09-05

    Dietary interventions are simple, non-invasive tools that can be utilized to improve health and lifespan. In this issue, Roberts et al. (2017) and Newman et al. (2017) reveal the physiological benefits of feeding mice ketogenic diets and suggest different underlying mechanisms that may promote healthy aging. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Longitudinal temperature distribution in an end-pumped solid-state amplifier medium: application to a high average power diode pumped Yb:YAG thin disk amplifier.

    Science.gov (United States)

    Bourdet, Gilbert L; Yu, Haiwu

    2007-08-10

    We propose a simple analytical derivation making it possible to compute a one-dimensional temperature variation in an end-pumped solid-state laser. This derivation takes into account the pump intensity variation along the crystal, the doping concentration, and temperature dependence of the thermal conductivity. We then compare this simulation with the one usually used, which does not take into account any of these dependences. The results show that, at room temperature, the two methods are in good agreement, but at a cryogenic temperature where the thermal conductivity varies fast with temperature, a large discrepancy is found, and the conventional computations underestimate both the average temperature and the longitudinal gradient.

  17. Diode-pumped continuous-wave and femtosecond Cr:LiCAF lasers with high average power in the near infrared, visible and near ultraviolet

    OpenAIRE

    Demirbas, Umit; Baali, Ilyes; Acar, Durmus Alp Emre; Leitenstorfer, Alfred

    2015-01-01

    We demonstrate continuous-wave (cw), cw frequency-doubled, cw mode-locked and Q-switched mode-locked operation of multimode diode-pumped Cr:LiCAF lasers with record average powers. Up to 2.54 W of cw output is obtained around 805 nm at an absorbed pump power of 5.5 W. Using intracavity frequency doubling with a BBO crystal, 0.9 W are generated around 402 nm, corresponding to an optical-to-optical conversion efficiency of 12%. With an intracavity birefringent tuning plate, the fundamental and ...

  18. Diode-pumped continuous-wave and femtosecond Cr:LiCAF lasers with high average power in the near infrared, visible and near ultraviolet.

    Science.gov (United States)

    Demirbas, Umit; Baali, Ilyes; Acar, Durmus Alp Emre; Leitenstorfer, Alfred

    2015-04-01

    We demonstrate continuous-wave (cw), cw frequency-doubled, cw mode-locked and Q-switched mode-locked operation of multimode diode-pumped Cr:LiCAF lasers with record average powers. Up to 2.54 W of cw output is obtained around 805 nm at an absorbed pump power of 5.5 W. Using intracavity frequency doubling with a BBO crystal, 0.9 W are generated around 402 nm, corresponding to an optical-to-optical conversion efficiency of 12%. With an intracavity birefringent tuning plate, the fundamental and frequency-doubled laser output is tuned continuously in a broad wavelength range from 745 nm to 885 nm and from 375 to 440 nm, respectively. A saturable Bragg reflector is used to initiate and sustain mode locking. In the cw mode-locked regime, the Cr:LiCAF laser produces 105-fs long pulses near 810 nm with an average power of 0.75 W. The repetition rate is 96.4 MHz, resulting in pulse energies of 7.7 nJ and peak powers of 65 kW. In Q-switched mode-locked operation, pulses with energies above 150 nJ are generated.

  19. Average transverse momenta of baryon production at p-p collider experiments and their crucial implications for the high energy hadroproduction physics

    CERN Document Server

    Piskounova, Olga I

    2016-01-01

    The phenomenological approach in the framework of Quark-Gluon String Model (QGSM) has been applied to the description of transverse momentum spectra for the various sorts of baryons in hadroproduction at colliders. The analysis of data on hyperon transverse momentum distributions,dN/dp_t, demonstrates a difference in the dynamics of multiparticle production in proton-proton vs. antiproton-proton collisions in the region of low p_t . The most important contribution in antip-p reaction goes from fragmentation of antidiquark-diquark side of pomeron diagram. The complete study of the energy dependence of average transverse momenta for the energies from sqrt(s)= 0.2 to 7. TeV shows the slight growing of with energy. No dramatic changes were seen on the range from Tevatron to LHC, which may be responsible for "knee" in the cosmic ray proton spectra. The average transverse momentum analysis through the different mass of hadrons reveals some regularity in the mass gaps between the hadron generations. This observatio...

  20. High-resolution AUV mapping and lava flow ages at Axial Seamount

    Science.gov (United States)

    Clague, D. A.; Paduan, J. B.; Dreyer, B. M.; Caress, D. W.; Martin, J.

    2011-12-01

    Mapping along mid-ocean ridges, as on land, requires identification of flow boundaries and sequence, and ages of some flows to understand eruption history. Multibeam sonars on autonomous underwater vehicles (AUV) now generate 1-m resolution maps that resolve lava pillars, internal flow structures and boundaries, and lava flow emplacement sequences using crosscutting relations and abundance of fissures. MBARI has now mapped the summit caldera floor and rims and the upper south rift zone on Axial Seamount on the Juan de Fuca Ridge. With the advent of the high-resolution bathymetry and the ability to observe flow contacts to determine superposition using ROVs and submersibles, the missing component has been determining absolute ages of the flows. We used the MBARI ROV Doc Ricketts to collect short push cores (<30 cm) of the thin sediment nestled between pillow lava lobes and sieve and then hand-pick planktic foraminifera from the base of the cores to date by AMS 14C. Ages of planktic foraminifera are marine-calibrated in years before present, and provide minimum ages for the underlying flows, as there is probably some basal sediment that is not recovered. 14C ages have been determined for 10 cores near the summit of Axial Seamount and for 6 from the lowermost south rift. Ages of nearby samples commonly yield statistically identical ages, and 2 cores near the center of the caldera had multiple layers dated. These ages systematically increase with depth, indicating that redistribution of sediment by bottom currents does not significantly affect the stratigraphy. We will expand these collections in summer 2011. The coring is accompanied by collection of flow samples for chemistry and video observations to confirm contact locations and flow superposition inferred from the mapping data. Six ages from the lowermost part of the south rift of Axial Seamount include samples on a cone with deep summit crater that is ~16,580 aBP and on 5 flows between 950 and 1510 aBP. Two

  1. ZPR-3 Assembly 12 : A cylindrical assembly of highly enriched uranium, depleted uranium and graphite with an average {sup 235}U enrichment of 21 atom %.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; McKnight, R. D.; Perel, R. L.; Wagschal, J. J.; Nuclear Engineering Division; Racah Inst. of Physics

    2010-09-30

    Over a period of 30 years, more than a hundred Zero Power Reactor (ZPR) critical assemblies were constructed at Argonne National Laboratory. The ZPR facilities, ZPR-3, ZPR-6, ZPR-9 and ZPPR, were all fast critical assembly facilities. The ZPR critical assemblies were constructed to support fast reactor development, but data from some of these assemblies are also well suited for nuclear data validation and to form the basis for criticality safety benchmarks. A number of the Argonne ZPR/ZPPR critical assemblies have been evaluated as ICSBEP and IRPhEP benchmarks. Of the three classes of ZPR assemblies, engineering mockups, engineering benchmarks and physics benchmarks, the last group tends to be most useful for criticality safety. Because physics benchmarks were designed to test fast reactor physics data and methods, they were as simple as possible in geometry and composition. The principal fissile species was {sup 235}U or {sup 239}Pu. Fuel enrichments ranged from 9% to 95%. Often there were only one or two main core diluent materials, such as aluminum, graphite, iron, sodium or stainless steel. The cores were reflected (and insulated from room return effects) by one or two layers of materials such as depleted uranium, lead or stainless steel. Despite their more complex nature, a small number of assemblies from the other two classes would make useful criticality safety benchmarks because they have features related to criticality safety issues, such as reflection by soil-like material. ZPR-3 Assembly 12 (ZPR-3/12) was designed as a fast reactor physics benchmark experiment with an average core {sup 235}U enrichment of approximately 21 at.%. Approximately 68.9% of the total fissions in this assembly occur above 100 keV, approximately 31.1% occur below 100 keV, and essentially none below 0.625 eV - thus the classification as a 'fast' assembly. This assembly is Fast Reactor Benchmark No. 9 in the Cross Section Evaluation Working Group (CSEWG) Benchmark

  2. High School Psychology: A Coming of Age Story

    Science.gov (United States)

    Keith, Kenneth D.; Hammer, Elizabeth Yost; Blair-Broeker, Charles T.; Ernst, Randal M.

    2013-01-01

    Although institutional recognition of high school psychology is fairly recent, psychology and psychological subject matters have a history dating to at least the 1830s. By the middle of the twentieth century, high school psychology courses existed in nearly all U.S. states, and enrollments grew throughout the second half of the century. However,…

  3. High School Psychology: A Coming of Age Story

    Science.gov (United States)

    Keith, Kenneth D.; Hammer, Elizabeth Yost; Blair-Broeker, Charles T.; Ernst, Randal M.

    2013-01-01

    Although institutional recognition of high school psychology is fairly recent, psychology and psychological subject matters have a history dating to at least the 1830s. By the middle of the twentieth century, high school psychology courses existed in nearly all U.S. states, and enrollments grew throughout the second half of the century. However,…

  4. Highly dynamically evolved intermediate-age open clusters

    CERN Document Server

    Piatti, Andrés E; Sampedro, Laura M

    2016-01-01

    We present a comprehensive UBVRI and Washington CT1T2 photometric analysis of seven catalogued open clusters, namely: Ruprecht 3, 9, 37, 74, 150, ESO 324-15 and 436-2. The multi-band photometric data sets in combination with 2MASS photometry and Gaia astrometry for the brighter stars were used to estimate their structural parameters and fundamental astrophysical properties. We found that Ruprecht 3 and ESO 436-2 do not show self-consistent evidence of being physical systems. The remained studied objects are open clusters of intermediate-age (9.0 < log(t yr-1) < 9.6), of relatively small size (r_cls ~ 0.4 - 1.3 pc) and placed between 0.6 and 2.9 kpc from the Sun. We analized the relationships between core, half-mass, tidal and Jacoby radii as well as half-mass relaxation times to conclude that the studied clusters are in an evolved dynamical stage. The cluster masses obtained by summing those of the observed cluster stars resulted to be ~ 10-15 per cent of the masses of open clusters of similar age locat...

  5. High Availability Solution: Resource Usage Management in Virtualized Software Aging

    Directory of Open Access Journals (Sweden)

    Aye Myat Myat Paing

    2012-07-01

    Full Text Available As businesses increasingly rely on IT for their mission-critical operations, continuous availability is auniversal concern. Nowadays, virtualized platform has become the popular option to deploy complexenough services. Deployed services are expected to be always, available, but these long running servicesare especially sensitive to suffer from software aging phenomenon. Software aging of virtual machinemonitors (VMMs is becoming critical because performance degradation or crash failure of a VMM affectsall virtual machines (VMs on it. To counteract this issue, we deploy software rejuvenation methodology.To eliminate the service outage during software rejuvenation process, we combine the rejuvenation withlive migration technology. Live VM migration enables a running VM on a host serer to move onto the otherhost server with very small interruption of the execution. Live VM migration depends on VMs placementand efficient resource available is required. The idea behind our paper is two-fold. First, we present theoptimization of the resource usage as accepting as many services as in virtualized environment whichsupport of VM live migration. Second, to demonstrate how much it can improve system availability, thestochastic Petri nets model a virtualized server system in case of using time based software rejuvenation forVMM is presented. Finally, we perform the numerical analysis to evaluate the model.

  6. Highly dynamically evolved intermediate-age open clusters

    Science.gov (United States)

    Piatti, Andrés E.; Dias, Wilton S.; Sampedro, Laura M.

    2017-04-01

    We present a comprehensive UBVRI and Washington CT1T2 photometric analysis of seven catalogued open clusters, namely: Ruprecht 3, 9, 37, 74, 150, ESO 324-15 and 436-2. The multiband photometric data sets in combination with 2MASS photometry and Gaia astrometry for the brighter stars were used to estimate their structural parameters and fundamental astrophysical properties. We found that Ruprecht 3 and ESO 436-2 do not show self-consistent evidence of being physical systems. The remained studied objects are open clusters of intermediate age (9.0 ≤ log(t yr-1) ≤ 9.6), of relatively small size (rcls ∼ 0.4-1.3 pc) and placed between 0.6 and 2.9 kpc from the Sun. We analysed the relationships between core, half-mass, tidal and Jacoby radii as well as half-mass relaxation times to conclude that the studied clusters are in an evolved dynamical stage. The total cluster masses obtained by summing those of the observed cluster stars resulted to be ∼10-15 per cent of the masses of open clusters of similar age located closer than 2 kpc from the Sun. We found that cluster stars occupy volumes as large as those for tidally filled clusters.

  7. Brain network characterization of high-risk preterm-born school-age children.

    Science.gov (United States)

    Fischi-Gomez, Elda; Muñoz-Moreno, Emma; Vasung, Lana; Griffa, Alessandra; Borradori-Tolsa, Cristina; Monnier, Maryline; Lazeyras, François; Thiran, Jean-Philippe; Hüppi, Petra S

    2016-01-01

    Higher risk for long-term cognitive and behavioral impairments is one of the hallmarks of extreme prematurity (EP) and pregnancy-associated fetal adverse conditions such as intrauterine growth restriction (IUGR). While neurodevelopmental delay and abnormal brain function occur in the absence of overt brain lesions, these conditions have been recently associated with changes in microstructural brain development. Recent imaging studies indicate changes in brain connectivity, in particular involving the white matter fibers belonging to the cortico-basal ganglia-thalamic loop. Furthermore, EP and IUGR have been related to altered brain network architecture in childhood, with reduced network global capacity, global efficiency and average nodal strength. In this study, we used a connectome analysis to characterize the structural brain networks of these children, with a special focus on their topological organization. On one hand, we confirm the reduced averaged network node degree and strength due to EP and IUGR. On the other, the decomposition of the brain networks in an optimal set of clusters remained substantially different among groups, talking in favor of a different network community structure. However, and despite the different community structure, the brain networks of these high-risk school-age children maintained the typical small-world, rich-club and modularity characteristics in all cases. Thus, our results suggest that brain reorganizes after EP and IUGR, prioritizing a tight modular structure, to maintain the small-world, rich-club and modularity characteristics. By themselves, both extreme prematurity and IUGR bear a similar risk for neurocognitive and behavioral impairment, and the here defined modular network alterations confirm similar structural changes both by IUGR and EP at school age compared to control. Interestingly, the combination of both conditions (IUGR + EP) does not result in a worse outcome. In such cases, the alteration in network

  8. Brain network characterization of high-risk preterm-born school-age children

    Directory of Open Access Journals (Sweden)

    Elda Fischi-Gomez

    2016-01-01

    Full Text Available Higher risk for long-term cognitive and behavioral impairments is one of the hallmarks of extreme prematurity (EP and pregnancy-associated fetal adverse conditions such as intrauterine growth restriction (IUGR. While neurodevelopmental delay and abnormal brain function occur in the absence of overt brain lesions, these conditions have been recently associated with changes in microstructural brain development. Recent imaging studies indicate changes in brain connectivity, in particular involving the white matter fibers belonging to the cortico-basal ganglia-thalamic loop. Furthermore, EP and IUGR have been related to altered brain network architecture in childhood, with reduced network global capacity, global efficiency and average nodal strength. In this study, we used a connectome analysis to characterize the structural brain networks of these children, with a special focus on their topological organization. On one hand, we confirm the reduced averaged network node degree and strength due to EP and IUGR. On the other, the decomposition of the brain networks in an optimal set of clusters remained substantially different among groups, talking in favor of a different network community structure. However, and despite the different community structure, the brain networks of these high-risk school-age children maintained the typical small-world, rich-club and modularity characteristics in all cases. Thus, our results suggest that brain reorganizes after EP and IUGR, prioritizing a tight modular structure, to maintain the small-world, rich-club and modularity characteristics. By themselves, both extreme prematurity and IUGR bear a similar risk for neurocognitive and behavioral impairment, and the here defined modular network alterations confirm similar structural changes both by IUGR and EP at school age compared to control. Interestingly, the combination of both conditions (IUGR + EP does not result in a worse outcome. In such cases, the alteration

  9. Ensemble Averaged Gravity Theory

    CERN Document Server

    Khosravi, Nima

    2016-01-01

    We put forward the idea that all the theoretically consistent models of gravity have a contribution to the observed gravity interaction. In this formulation each model comes with its own Euclidean path integral weight where general relativity (GR) automatically has the maximum weight in high-curvature regions. We employ this idea in the framework of Lovelock models and show that in four dimensions the result is a specific form of $f(R,G)$ model. This specific $f(R,G)$ satisfies the stability conditions and has self-accelerating solution. Our model is consistent with the local tests of gravity since its behavior is same as GR for high-curvature regimes. In low-curvature regime the gravity force is weaker than GR which can interpret as existence of a repulsive fifth force for very large scales. Interestingly there is an intermediate-curvature regime where the gravity force is stronger in our model than GR. The different behavior of our model in comparison with GR in both low- and intermediate-curvature regimes ...

  10. Diffusion Bonded KTiOPO4 Crystal for the Second Harmonic Generation of High Average Power Zigzag Slab Nd:YAG Laser

    Science.gov (United States)

    Tei, Kazuyoku; Kato, Masaaki; Matsuoka, Fumiaki; Niwa, Yosito; Maruyama, Yoichiro; Matoba, Tohru; Arisawa, Takasi

    1999-01-01

    For the second harmonic generation (SHG) of a high-repetition rate and high pulse energy zigzag slab Nd:YAG laser, the direct bonding of two KTiPO4 (KTP) crystals is carried out and their characteristics are studied using the zigzag slab laser that produces 2.1 J energy pulses with a beam having a rectangular cross section at a pulse repetition rate of 100 Hz. Although an angle mismatch of four minutes between two tuning curves is observed for the bonded crystals, the energy conversion efficiency is the same as that of a single KTP crystal. The second harmonic produced is 1 J.

  11. Prevalence of sleep duration on an average school night among 4 nationally representative successive samples of American high school students, 2007-2013.

    Science.gov (United States)

    Basch, Charles E; Basch, Corey H; Ruggles, Kelly V; Rajan, Sonali

    2014-12-11

    Consistency, quality, and duration of sleep are important determinants of health. We describe sleep patterns among demographically defined subgroups from the Youth Risk Behavior Surveillance System reported in 4 successive biennial representative samples of American high school students (2007 to 2013). Across the 4 waves of data collection, 6.2% to 7.7% of females and 8.0% to 9.4% of males reported obtaining 9 or more hours of sleep. Insufficient duration of sleep is pervasive among American high school students. Despite substantive public health implications, intervention research on this topic has received little attention.

  12. Dry aging of beef in a bag highly permeable to water vapour.

    Science.gov (United States)

    Ahnström, Maria Lundesjö; Seyfert, Mark; Hunt, Melvin C; Johnson, Dallas E

    2006-08-01

    The objective of this experiment was to compare traditional dry aging of beef with a novel technique of dry aging in a highly moisture-permeable bag. Four equal-sized sections from paired beef strip loins were dry aged traditionally, unpackaged, or packaged in the experimental bag for 14 or 21d at 3°C. No differences (P>0.05) were noted for pH, moisture, fat, total plate counts, cook loss, shear force, or any measured sensory attribute between the two aging treatments after either aging period. After 21d, however, dry aging in the bag (versus traditional dry aging) decreased (PDry aging in a highly moisture-permeable bag is feasible, will positively impact yields and reduce microbial spoilage, and will have no negative impact on product quality.

  13. Short-lived high-amplitude cooling on Svalbard during the Dark Ages

    Science.gov (United States)

    van der Bilt, Willem; D`Andrea, William; Bakke, Jostein; Balascio, Nicholas; Werner, Johannes; Hoek, Wim

    2016-04-01

    As the paradigm of a stable Holocene climate has shifted, an increasing number of high-resolution proxy timeseries reveal dynamic conditions, characterized by high-amplitude climate shifts. Some of these events occurred during historical times and allow us to study the interaction between environmental and cultural change, providing valuable lessons for the near future. These include the Dark Ages Cold Period (DACP) between 300 and 800 AD, a period marked by political upheaval and climate instability that remains poorly investigated. Here, we present two temperature reconstructions from the High Arctic Svalbard Archipelago. To this end, we applied the established alkenone-based UK37 paleothermometer on sediments from two lakes on western Spitsbergen, Lake Hajeren and Lake Hakluyt. The Arctic is presently warming twice as fast as the global average and proxy data as well as model simulations suggest that this amplified response is characteristic for regional climate. The Arctic therefore provides a uniquely sensitive environment to study relatively modest climate shifts, like the DACP, that may not be adequately captured at lower-latitude sites. Owing to undisturbed sediments, a high sampling resolution and robust chronological control, the presented reconstructions resolve the attendant sub-centennial-scale climate shifts. Our findings suggest that the DACP marks a cold spell within the cool Neoglacial period, which started some 4 ka BP on Svalbard. Close investigation reveals a distinct temperature minimum around 500 AD that is reproduced in another alkenone-based temperature reconstruction from a nearby lake. At ± 1.75 °C, cooling underlines the sensitivity of Arctic climate as well as the magnitude of the DACP.

  14. Aging and Embrittlement of High Fluence Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Was, gary; Jiao, Zhijie; der ven, Anton Van; Bruemmer, Stephen; Edwards, Dan

    2012-12-31

    Irradiation of austenitic stainless steels results in the formation of dislocation loops, stacking fault tetrahedral, Ni-Si clusters and radiation-induced segregation (RIS). Of these features, it is the formation of precipitates which is most likely to impact the mechanical integrity at high dose. Unlike dislocation loops and RIS, precipitates exhibit an incubation period that can extend from 10 to 46 dpa, above which the cluster composition changes and a separate phase, (G-phase) forms. Both neutron and heavy ion irradiation showed that these clusters develop slowly and continue to evolve beyond 100 dpa. Overall, this work shows that the irradiated microstructure features produced by heavy ion irradiation are remarkably comparable in nature to those produced by neutron irradiation at much lower dose rates. The use of a temperature shift to account for the higher damage rate in heavy ion irradiation results in a fairly good match in the dislocation loop microstructure and the precipitate microstructure in austenitic stainless steels. Both irradiations also show segregation of the same elements and in the same directions, but to achieve comparable magnitudes, heavy ion irradiation must be conducted at a much higher temperature than that which produces a match with loops and precipitates. First-principles modeling has confirmed that the formation of Ni-Si precipitates under irradiation is likely caused by supersaturation of solute to defect sinks caused by highly correlated diffusion of Ni and Si. Thus, the formation and evolution of Ni-Si precipitates at high dose in austenitic stainless steels containing Si is inevitable.

  15. High accuracy digital aging monitor based on PLL-VCO circuit

    Science.gov (United States)

    Yuejun, Zhang; Zhidi, Jiang; Pengjun, Wang; Xuelong, Zhang

    2015-01-01

    As the manufacturing process is scaled down to the nanoscale, the aging phenomenon significantly affects the reliability and lifetime of integrated circuits. Consequently, the precise measurement of digital CMOS aging is a key aspect of nanoscale aging tolerant circuit design. This paper proposes a high accuracy digital aging monitor using phase-locked loop and voltage-controlled oscillator (PLL-VCO) circuit. The proposed monitor eliminates the circuit self-aging effect for the characteristic of PLL, whose frequency has no relationship with circuit aging phenomenon. The PLL-VCO monitor is implemented in TSMC low power 65 nm CMOS technology, and its area occupies 303.28 × 298.94 μm2. After accelerating aging tests, the experimental results show that PLL-VCO monitor improves accuracy about high temperature by 2.4% and high voltage by 18.7%.

  16. Excluded volume effect of counterions and water dipoles near a highly charged surface due to a rotationally averaged Boltzmann factor for water dipoles.

    Science.gov (United States)

    Gongadze, Ekaterina; Iglič, Aleš

    2013-03-01

    Water ordering near a negatively charged electrode is one of the decisive factors determining the interactions of an electrode with the surrounding electrolyte solution or tissue. In this work, the generalized Langevin-Bikerman model (Gongadze-Iglič model) taking into account the cavity field and the excluded volume principle is used to calculate the space dependency of ions and water number densities in the vicinity of a highly charged surface. It is shown that for high enough surface charged densities the usual trend of increasing counterion number density towards the charged surface may be completely reversed, i.e. the drop in the counterions number density near the charged surface is predicted.

  17. Evidence of alpha fluctuations in myoglobin's denaturation in the high temperature region: Average relaxation time from an Adam-Gibbs perspective.

    Science.gov (United States)

    Olivares-Quiroz, Luis; Garcia-Colin, Leopoldo S

    2009-10-01

    In this work, we derive an analytical expression for the relaxation time tau as a function of temperature T for myoglobin protein (Mb, PDB:1MBN) in the high temperature limit (T>T(g)=200K). The method is based on a modified version of the Adam-Gibbs theory (AG theory) for the glass transition in supercooled liquids and an implementation of differential geometry techniques. This modified version of the AG theory takes into account that the entropic component in protein's denaturation has two major sources: a configurational contribution DeltaS(c) due to the unfolding of the highly ordered native state N and a hydration contribution DeltaS(hyd) arising from the exposure of non-polar residues to direct contact with solvent polar molecules. Our results show that the configurational contribution DeltaS(c) is temperature-independent and one order of magnitude smaller than its hydration counterpart DeltaS(hyd) in the temperature range considered. The profile obtained for log tau(T) from T=200 K to T=300 K exhibits a non-Arrhenius behavior characteristic of alpha relaxation mechanisms in hydrated proteins and glassy systems. This result is in agreement with recent dielectric spectroscopy data obtained for hydrated myoglobin, where at least two fast relaxation processes in the high temperature limit have been observed. The connection between the relaxation process calculated here and the experimental results is outlined.

  18. Area-averaged evapotranspiration over a heterogeneous land surface: aggregation of multi-point EC flux measurements with a high-resolution land-cover map and footprint analysis

    Science.gov (United States)

    Xu, Feinan; Wang, Weizhen; Wang, Jiemin; Xu, Ziwei; Qi, Yuan; Wu, Yueru

    2017-08-01

    The determination of area-averaged evapotranspiration (ET) at the satellite pixel scale/model grid scale over a heterogeneous land surface plays a significant role in developing and improving the parameterization schemes of the remote sensing based ET estimation models and general hydro-meteorological models. The Heihe Watershed Allied Telemetry Experimental Research (HiWATER) flux matrix provided a unique opportunity to build an aggregation scheme for area-averaged fluxes. On the basis of the HiWATER flux matrix dataset and high-resolution land-cover map, this study focused on estimating the area-averaged ET over a heterogeneous landscape with footprint analysis and multivariate regression. The procedure is as follows. Firstly, quality control and uncertainty estimation for the data of the flux matrix, including 17 eddy-covariance (EC) sites and four groups of large-aperture scintillometers (LASs), were carefully done. Secondly, the representativeness of each EC site was quantitatively evaluated; footprint analysis was also performed for each LAS path. Thirdly, based on the high-resolution land-cover map derived from aircraft remote sensing, a flux aggregation method was established combining footprint analysis and multiple-linear regression. Then, the area-averaged sensible heat fluxes obtained from the EC flux matrix were validated by the LAS measurements. Finally, the area-averaged ET of the kernel experimental area of HiWATER was estimated. Compared with the formerly used and rather simple approaches, such as the arithmetic average and area-weighted methods, the present scheme is not only with a much better database, but also has a solid grounding in physics and mathematics in the integration of area-averaged fluxes over a heterogeneous surface. Results from this study, both instantaneous and daily ET at the satellite pixel scale, can be used for the validation of relevant remote sensing models and land surface process models. Furthermore, this work will be

  19. Tall Poppies: Bullying Behaviors Faced by Australian High-Performance School-Age Athletes

    Science.gov (United States)

    O'Neill, Maureen; Calder, Angela; Allen, Bill

    2014-01-01

    Little is known about Australian high-performance school-age athletes' experiences as victims of the tall poppy syndrome. Tall poppies are successful individuals bullied by those who are less successful in order to "normalize them." Nineteen current or previous national or international high-performance school-age athletes were…

  20. Education of Social Skills among Senior High School Age Students in Physical Education Classes

    Science.gov (United States)

    Akelaitis, Arturas V.; Malinauskas, Romualdas K.

    2016-01-01

    Research aim was to reveal peculiarities of the education of social skills among senior high school age students in physical education classes. We hypothesized that after the end of the educational experiment the senior high school age students will have more developed social skills in physical education classes. Participants in the study were 51…

  1. Differential Effects on Student Demographic Groups of Using ACT® College Readiness Assessment Composite Score, Act Benchmarks, and High School Grade Point Average for Predicting Long-Term College Success through Degree Completion. ACT Research Report Series, 2013 (5)

    Science.gov (United States)

    Radunzel, Justine; Noble, Julie

    2013-01-01

    In this study, we evaluated the differential effects on racial/ethnic, family income, and gender groups of using ACT® College Readiness Assessment Composite score and high school grade point average (HSGPA) for predicting long-term college success. Outcomes included annual progress towards a degree (based on cumulative credit-bearing hours…

  2. Inferring Average Ground Profiles of the Muon Density of Inclined Air Showers from Monte-Carlo Simulations at Ultra-High Energy

    CERN Document Server

    Dembinski, Hans; Deligny, Olivier; Hebbeker, Thomas

    2009-01-01

    A standard method to measure ultra-high energy cosmic rays is the sampling of the ground particle profile of the extensive air shower that is produced in the atmosphere with an array of surface detectors. The primary energy of inclined air showers with zenith angles >60 Deg can be reconstructed by using simulated 2-D profiles of the ground density of muons. We will present an effective way to extract such profiles from a library of Monte-Carlo simulated air showers. Also, we will demonstrate a way to speed up the simulation of ground profiles of the muon density in very inclined showers by three orders of magnitude, if only the muon component in the shower is of interest.

  3. From cradle to grave: high-throughput studies of aging in model organisms.

    Science.gov (United States)

    Spivey, Eric C; Finkelstein, Ilya J

    2014-07-01

    Aging-the progressive decline of biological functions-is a universal fact of life. Decades of intense research in unicellular and metazoan model organisms have highlighted that aging manifests at all levels of biological organization - from the decline of individual cells, to tissue and organism degeneration. To better understand the aging process, we must first aim to integrate quantitative biological understanding on the systems and cellular levels. A second key challenge is to then understand the many heterogeneous outcomes that may result in aging cells, and to connect cellular aging to organism-wide degeneration. Addressing these challenges requires the development of high-throughput aging and longevity assays. In this review, we highlight the emergence of high-throughput aging approaches in the most commonly used model organisms. We conclude with a discussion of the critical questions that can be addressed with these new methods.

  4. Physical Theories with Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2013-01-01

    This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violat...

  5. Average Convexity in Communication Situations

    NARCIS (Netherlands)

    Slikker, M.

    1998-01-01

    In this paper we study inheritance properties of average convexity in communication situations. We show that the underlying graph ensures that the graphrestricted game originating from an average convex game is average convex if and only if every subgraph associated with a component of the underlyin

  6. Vertical Gradients in Water Chemistry and Age in the Southern High Plains Aquifer, Texas, 2002

    Science.gov (United States)

    McMahon, P.B.; Böhlke, J.K.; Lehman, T.M.

    2004-01-01

    The southern High Plains aquifer is the primary source of water used for domestic, industrial, and irrigation purposes in parts of New Mexico and Texas. Despite the aquifer's importance to the overall economy of the southern High Plains, fundamental ground-water characteristics, such as vertical gradients in water chemistry and age, remain poorly defined. As part of the U.S. Geological Survey's National Water-Quality Assessment Program, water samples from nested, short-screen monitoring wells installed in the southern High Plains aquifer at two locations (Castro and Hale Counties, Texas) were analyzed for field parameters, major ions, nutrients, trace elements, dissolved organic carbon, pesticides, stable and radioactive isotopes, and dissolved gases to evaluate vertical gradients in water chemistry and age in the aquifer. Tritium measurements indicate that recent (post-1953) recharge was present near the water table and that deeper water was recharged before 1953. Concentrations of dissolved oxygen were largest (2.6 to 5.6 milligrams per liter) at the water table and decreased with depth below the water table. The smallest concentrations were less than 0.5 milligram per liter. The largest major-ion concentrations generally were detected at the water table because of the effects of overlying agricultural activities, as indicated by postbomb tritium concentrations and elevated nitrate and pesticide concentrations at the water table. Below the zone of agricultural influence, major-ion concentrations exhibited small increases with depth and distance along flow paths because of rock/water interactions and mixing with water from the underlying aquifer in rocks of Cretaceous age. The concentration increases primarily were accounted for by dissolved sodium, bicarbonate, chloride, and sulfate. Nitrite plus nitrate concentrations at the water table were 2.0 to 6.1 milligrams per liter as nitrogen, and concentrations substantially decreased with depth in the aquifer to a

  7. Sampling Based Average Classifier Fusion

    Directory of Open Access Journals (Sweden)

    Jian Hou

    2014-01-01

    fusion algorithms have been proposed in literature, average fusion is almost always selected as the baseline for comparison. Little is done on exploring the potential of average fusion and proposing a better baseline. In this paper we empirically investigate the behavior of soft labels and classifiers in average fusion. As a result, we find that; by proper sampling of soft labels and classifiers, the average fusion performance can be evidently improved. This result presents sampling based average fusion as a better baseline; that is, a newly proposed classifier fusion algorithm should at least perform better than this baseline in order to demonstrate its effectiveness.

  8. Spatial filters for high average power lasers

    Science.gov (United States)

    Erlandson, Alvin C

    2012-11-27

    A spatial filter includes a first filter element and a second filter element overlapping with the first filter element. The first filter element includes a first pair of cylindrical lenses separated by a first distance. Each of the first pair of cylindrical lenses has a first focal length. The first filter element also includes a first slit filter positioned between the first pair of cylindrical lenses. The second filter element includes a second pair of cylindrical lenses separated by a second distance. Each of the second pair of cylindrical lenses has a second focal length. The second filter element also includes a second slit filter positioned between the second pair of cylindrical lenses.

  9. Detrimental effects of a high fat/high cholesterol diet on memory and hippocampal markers in aged rats.

    Science.gov (United States)

    Ledreux, Aurélie; Wang, Xiuzhe; Schultzberg, Marianne; Granholm, Ann-Charlotte; Freeman, Linnea R

    2016-10-01

    High fat diets have detrimental effects on cognitive performance, and can increase oxidative stress and inflammation in the brain. The aging brain provides a vulnerable environment to which a high fat diet could cause more damage. We investigated the effects of a high fat/high cholesterol (HFHC) diet on cognitive performance, neuroinflammation markers, and phosphorylated Tau (p-Tau) pathological markers in the hippocampus of Young (4-month old) versus Aged (14-month old) male rats. Young and Aged male Fisher 344 rats were fed a HFHC diet or a normal control diet for 6 months. All animals underwent cognitive testing for 12days in a water radial arm maze to assess spatial and working reference memory. Hippocampal tissue was analyzed by immunohistochemistry for structural changes and inflammation, and Western blot analysis. Young and Aged rats fed the HFHC diet exhibited worse performance on a spatial working memory task. They also exhibited significant reduction of NeuN and calbindin-D28k immunoreactivity as well as an increased activation of microglial cells in the hippocampal formation. Western blot analysis of the hippocampus showed higher levels of p-Tau S202/T205 and T231 in Aged HFHC rats, suggesting abnormal phosphorylation of Tau protein following the HFHC diet exposure. This work demonstrates HFHC diet-induced cognitive impairment with aging and a link between high fat diet consumption and pathological markers of Alzheimer's disease.

  10. Age of Sexual Debut and Physical Dating Violence Victimization: Sex Differences among US High School Students

    Science.gov (United States)

    Ihongbe, Timothy O.; Cha, Susan; Masho, Saba W.

    2017-01-01

    Background: Research has shown that early age of sexual debut is associated with physical dating violence (PDV), but sex-specific associations are sparse. We estimated the prevalence of PDV victimization in high school students who have initiated sexual intercourse and examined sex-specific association between age of sexual debut and PDV…

  11. Sleep Patterns of School-Age Children with Asperger Syndrome or High-Functioning Autism

    Science.gov (United States)

    Allik, Hiie; Larsson, Jan-Olov; Smedje, Hans

    2006-01-01

    Sleep patterns of 32 school-age children with Asperger syndrome (AS) and high-functioning autism (HFA) were compared to those of 32 typically developing age- and gender-matched children, using parent survey and one week of diary and actigraphic monitoring. Parents of children with AS/HFA more commonly reported that their children had difficulty…

  12. Age of Sexual Debut and Physical Dating Violence Victimization: Sex Differences among US High School Students

    Science.gov (United States)

    Ihongbe, Timothy O.; Cha, Susan; Masho, Saba W.

    2017-01-01

    Background: Research has shown that early age of sexual debut is associated with physical dating violence (PDV), but sex-specific associations are sparse. We estimated the prevalence of PDV victimization in high school students who have initiated sexual intercourse and examined sex-specific association between age of sexual debut and PDV…

  13. Pb-Pb zircon ages of the Porto Nacional high-grade metamorphic terrain, northern portion of the Goias Massif, central Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Gorayeb, Paulo Sergio de Sousa; Moura, Candido Augusto Veloso [Para Univ., Belem, PA (Brazil). Centro de Geociencias]. E-mail: gorayebp@ufpa.br; c_moura@ufpa.br; Barros, Gisele Ribeiro de [Para Univ., Belem, PA (Brazil). Programa Institucional de Bolsas de Iniciacao Cientifica (PIBIC)]. E-mail: agbarros@amazon.com.br

    2000-03-01

    Single zircon Pb-evaporation ages were determined for a mafic granulite, two enderbites and a kinzigite of the Porto Nacional High-Grade Metamorphic Terrain (PNHGT) in the Goias massif. Zircons from mafic granulites and one of the enderbites of yielded average {sup 207} Pb/{sup 206} Pb ages of 2125{+-}3 Ma and 2153{+-}1 Ma, respectively, being interpreted as minimum ages of the igneous protoliths. The other enderbite, whose zircons presented round terminations, yielded an average {sup 207} Pb/{sup 206} Pb age of 2097 {+-} 2 Ma. Zircons from the kinzigite, displaying cores and rims overgrowth, presented {sup 207} Pb/{sup 206} Pb ages ranging between 2027 and 2115 Ma. However, a very homogeneous zircon crystal without overgrowth yielded age of 2100 {+-} 2 Ma, with a distinctive low Th/U value (0.02). This zircon is interpreted as a metamorphic crystal and its age probably sets the age of the granulite facies metamorphism, indicating that the PNHGT is a result of the Transamazonian thermotectonic event. (author)

  14. High-frequency hearing thresholds: effects of age, occupational ultrasound and noise exposure.

    Science.gov (United States)

    Maccà, Isabella; Scapellato, Maria Luisa; Carrieri, Mariella; Maso, Stefano; Trevisan, Andrea; Bartolucci, Giovanni Battista

    2015-02-01

    It has been suggested that high-frequency audiometry (HFA) could represent a useful preventive measure in exposed workers. The aim was to investigate the effects of age, ultrasound and noise on high-frequency hearing thresholds. We tested 24 industrial ultrasound-exposed subjects, 113 industrial noise-exposed subjects and 148 non-exposed subjects. Each subject was tested with both conventional-frequency (0.125-8 kHz) and high-frequency (9-18 kHz) audiometry. The hearing threshold at high frequency deteriorated as a function of age, especially in subjects more than 30 years old. The ultrasound-exposed subjects had significantly higher hearing thresholds than the non-exposed ones at the high frequencies, being greatest from 10 to 14 kHz. This hearing loss was already significantly evident in subjects with exposure frequencies 4 and 6 kHz and at the high frequency of 14 kHz. After stratification for age, there was a significant difference between the two groups at 9-10 and 14-15 kHz only for those under 30 years of age. Multivariate analysis indicated that age was the primary predictor, and noise and ultrasound exposure the secondary predictors of hearing thresholds in the high-frequency range. The results suggest that HFA could be useful in the early diagnosis of noise-induced hearing loss in younger groups of workers (under 30 years of age).

  15. Physical Theories with Average Symmetry

    CERN Document Server

    Alamino, Roberto C

    2013-01-01

    This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violations of physical symmetries, as for instance Lorentz invariance in some quantum gravity theories, is briefly commented.

  16. An Epidemiological Profile Of Diabetes Mellitus Amongst High Risk Age Group - A Community Based Study

    OpenAIRE

    Nadeem Ahmad; Suresh Chandra; R P Sharma; J P Srivastava; S C Saxena

    2004-01-01

    Research Question : What is the epidemiological profile of Diabetes mellitus amongst high-risk age group population in urban and rural areas of Kanpur.Objectives : To study the prevalence, magnitude, possible associates and socio demographic variables related to Diabetes mellitus amongst the high risk age group population in urban and rural areas of Kanpur.Study Design : Cross-sectional study.Setting : The study was performed on five thousand population each in urban and rural areas of Kanpur...

  17. High-field proton magnetic resonance spectroscopy reveals metabolic effects of normal brain aging.

    Science.gov (United States)

    Harris, Janna L; Yeh, Hung-Wen; Swerdlow, Russell H; Choi, In-Young; Lee, Phil; Brooks, William M

    2014-07-01

    Altered brain metabolism is likely to be an important contributor to normal cognitive decline and brain pathology in elderly individuals. To characterize the metabolic changes associated with normal brain aging, we used high-field proton magnetic resonance spectroscopy in vivo to quantify 20 neurochemicals in the hippocampus and sensorimotor cortex of young adult and aged rats. We found significant differences in the neurochemical profile of the aged brain when compared with younger adults, including lower aspartate, ascorbate, glutamate, and macromolecules, and higher glucose, myo-inositol, N-acetylaspartylglutamate, total choline, and glutamine. These neurochemical biomarkers point to specific cellular mechanisms that are altered in brain aging, such as bioenergetics, oxidative stress, inflammation, cell membrane turnover, and endogenous neuroprotection. Proton magnetic resonance spectroscopy may be a valuable translational approach for studying mechanisms of brain aging and pathology, and for investigating treatments to preserve or enhance cognitive function in aging.

  18. Quantized average consensus with delay

    NARCIS (Netherlands)

    Jafarian, Matin; De Persis, Claudio

    2012-01-01

    Average consensus problem is a special case of cooperative control in which the agents of the network asymptotically converge to the average state (i.e., position) of the network by transferring information via a communication topology. One of the issues of the large scale networks is the cost of co

  19. Age and growth of the sand lizards (Lacerta agilis from a high Alpine population of north-western Italy

    Directory of Open Access Journals (Sweden)

    Fabio M. Guarino

    2010-07-01

    Full Text Available We studied growth and longevity of Lacerta agilis from a sample (34 adults and 2 small-sized juveniles of a population living at high altitude in north-western Italy using skeletochronological method. Snout vent length (SVL mean of males did not significantly differ from that of females although the latter were in average bigger (SVL ± SD, males: 69.3 ± 7.1 mm, n = 11; females: 73.9 ± 9.7 mm, n = 22; Mann-Whitney U-test, U = 1.76, P = 0.077. Age ranged from 2 to 4 years (mean age ± SD = 2.3 ± 0.2 in males and from 2 to 3 years in females (mean age ± SD = 2.59 ± 0.5 years. Age mean did not significantly differ between the sexes (Mann-Whitney U-test, U = 1.35, P = 0.174. The two juveniles were 30 and 32 mm in SVL and both were 1-2 months old. In both sexes, a significant positive correlation between SVL and age was recorded although weakly significant for males (Spearman’s correlation coefficient, males: rs = 0.70, P = 0.05; females: rs = 0.75, P < 0.001. Von Bertalanffy growth curves well fitted to the relationships between age and SVL and showed a different profile between males (asymptotics size, SVLmax = 81.9 mm; growth coefficient, k = 0.63 and females (SVLmax = 100 mm; k = 0.40. Results indicate that individuals of L. agilis studied by us are short-living when compared with other populations of the same species.

  20. Age dependency of myocardial triglyceride content. A 3T high-field {sup 1}H-MR spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Petritsch, B.; Gassenmaier, T.; Kunz, A.S.; Donhauser, J.; Bley, T.A.; Horn, M. [University Hospital of Wuerzburg (Germany). Inst. of Diagnostic and Interventional Radiology; Goltz, J.P. [University Hospital of Schleswig-Holstein, Campus Luebeck (Germany). Clinic for Radiology and Nuclear Medicine

    2015-11-15

    The role of myocardial triglyceride (mTG) content in the aging human heart is not entirely understood. The aim of this study was to measure concentrations of mTG content from healthy volunteers and to determine the association between age, mTG content and systolic heart function. Furthermore, the technical stability of the {sup 1}H-magnetic resonance spectroscopy ({sup 1}H-MRS) and the reliability of peak evaluation at 3 T were evaluated. The total study population of 47 healthy volunteers was divided into 4 age classes, according to the age of the subjects (1{sup st} cohort 20-29 years (yrs.), n=20; 2{sup nd} cohort 30-39 yrs., n=10; 3{sup rd} cohort 40-49 yrs., n=9; 4{sup th} cohort 50-60 yrs., n=8). Cardiac MRI and double triggered {sup 1}H-MRS of the myocardium were consecutively performed using a 3 T scanner. Each participant underwent spectroscopic measurements twice in the same investigation. mTG content increases with age. The correlation of age and mTG is minimal (r=0.48; p<0.001). The following age-averaged mTG content values expressed as % of mTG signal compared to the water signal were determined for each cohort: 1{sup st} cohort 0.25 % (± 0.17); 2{sup nd} cohort 0.48 % (± 0.30); 3{sup rd} cohort 0.48 % (± 0.18); 4{sup th} cohort 0.77 % (± 0.70). There was no significant correlation (r=0.04; p=n.s.) between LV mass and mTG content in healthy volunteers. Within our cohorts, no effects of age or mTG content on systolic heart function were seen (r=-0.01; p=n.s.). The intraclass correlation coefficient of spectroscopic measurements was high (r=0.965; p<0.001). Myocardial TG content increases with age. The normal age-dependent concentration ranges of myocardial lipid metabolites reported in this study may be helpful for the correction of acquired {sup 1}H-MRS data in patients when evaluating metabolic and cardiovascular diseases in future magnetic resonance spectroscopy studies.

  1. Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet.

    Science.gov (United States)

    Kesby, James P; Kim, Jane J; Scadeng, Miriam; Woods, Gina; Kado, Deborah M; Olefsky, Jerrold M; Jeste, Dilip V; Achim, Cristian L; Semenova, Svetlana

    2015-01-01

    Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD) exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old) and aged (15 months old) mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions.

  2. Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet.

    Directory of Open Access Journals (Sweden)

    James P Kesby

    Full Text Available Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old and aged (15 months old mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions.

  3. All-fiber high-average power nanosecond-pulsed master-oscillator power amplifier at 2  μm with mJ-level pulse energy.

    Science.gov (United States)

    Wang, Xiong; Jin, Xiaoxi; Zhou, Pu; Wang, Xiaolin; Xiao, Hu; Liu, Zejin

    2016-03-10

    We present a high-power nanosecond-pulsed Tm-doped fiber amplifier at 1.971 μm based on a master-oscillator power amplifier (MOPA) configuration. When the repetition rate is 500 kHz and the pulse width is 63.3 ns, the average power reaches 238 W, the peak power reaches 7.06 kW, and the pulse energy is 0.477 mJ. When the pulse train's repetition rate is 300 kHz with a pulse width of 63.7 ns, the average power reaches 197 W, the peak power reaches 9.73 kW, and the pulse energy is 0.66 mJ. When the pulse train's repetition rate is 200 kHz with a pulse width of 58.2 ns, the average power reaches 150 W, the peak power reaches 12.1 kW, and the pulse energy is 0.749 mJ. The spectral linewidths of the pulse trains are 0.15, 0.14, and 0.10 nm for 500 kHz repetition rate, 300 kHz repetition rate, and 200 kHz repetition rate, respectively. To the best of our knowledge, this is the first demonstration of high-power nanosecond-pulsed MOPA at 2 μm with the maximum average power reaching 238 W, the maximum peak power reaching 12.1 kW, and the maximum pulse energy reaching 0.749 mJ.

  4. High-demand jobs: age-related diversity in work ability?

    Science.gov (United States)

    Sluiter, Judith K

    2006-07-01

    High-demand jobs include 'specific' job demands that are not preventable with state of the art ergonomics knowledge and may overburden the bodily capacities, safety or health of workers. An interesting question is whether the age of the worker is an important factor in explanations of diversity in work ability in the context of high-demand jobs. In this paper, the work ability of ageing workers is addressed according to aspects of diversity in specific job demands and the research methods that are needed to shed light upon the relevant associated questions. From the international literature, a body of evidence was elicited concerning rates of chronological ageing in distinct bodily systems and functions. Intra-age-cohort differences in capacities and work ability, however, require (not yet existing) valid estimates of functional age or biological age indices for the specific populations of workers in high-demand jobs. Many studies have drawn on the highly demanding work of fire-fighters, ambulance workers, police officers, medical specialists, pilots/astronauts and submarine officers. Specific job demands in these jobs can be physical, mental or psychosocial in origin but may cause combined task-level loadings. Therefore, the assessment of single demands probably will not reveal enough relevant information about work ability in high-demand jobs and there will be a call for more integrated measures. Existing studies have used a variety of methodologies to address parts of the issue: task analyses for quantifying physical work demands, observations of psychological and physiological parameters, measures of psychosocial work demands and health complaints. Specific details about the work ability of ageing workers in high-demand jobs are scarce. In general, specific demands are more likely to overtax the capacities of older workers than those of younger workers in high-demand jobs, implying greater repercussions for health, although these effects also vary considerably

  5. Manga High: Literacy, Identity, and Coming of Age in an Urban High School

    Science.gov (United States)

    Bitz, Michael

    2009-01-01

    Based on a four-year study, "Manga High" explores the convergence of literacy, creativity, social development, and personal identity in one of New York City's largest high schools. Since 2004, students at Martin Luther King, Jr., High School in Manhattan have been creating manga--Japanese comic books. They write the stories, design the…

  6. Manga High: Literacy, Identity, and Coming of Age in an Urban High School

    Science.gov (United States)

    Bitz, Michael

    2009-01-01

    Based on a four-year study, "Manga High" explores the convergence of literacy, creativity, social development, and personal identity in one of New York City's largest high schools. Since 2004, students at Martin Luther King, Jr., High School in Manhattan have been creating manga--Japanese comic books. They write the stories, design the…

  7. Manga High: Literacy, Identity, and Coming of Age in an Urban High School

    Science.gov (United States)

    Bitz, Michael

    2009-01-01

    Based on a four-year study, "Manga High" explores the convergence of literacy, creativity, social development, and personal identity in one of New York City's largest high schools. Since 2004, students at Martin Luther King, Jr., High School in Manhattan have been creating manga--Japanese comic books. They write the stories, design the characters,…

  8. Gaussian moving averages and semimartingales

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas

    2008-01-01

    In the present paper we study moving averages (also known as stochastic convolutions) driven by a Wiener process and with a deterministic kernel. Necessary and sufficient conditions on the kernel are provided for the moving average to be a semimartingale in its natural filtration. Our results...... are constructive - meaning that they provide a simple method to obtain kernels for which the moving average is a semimartingale or a Wiener process. Several examples are considered. In the last part of the paper we study general Gaussian processes with stationary increments. We provide necessary and sufficient...

  9. An Epidemiological Profile Of Diabetes Mellitus Amongst High Risk Age Group - A Community Based Study

    Directory of Open Access Journals (Sweden)

    Nadeem Ahmad

    2004-06-01

    Full Text Available Research Question : What is the epidemiological profile of Diabetes mellitus amongst high-risk age group population in urban and rural areas of Kanpur.Objectives : To study the prevalence, magnitude, possible associates and socio demographic variables related to Diabetes mellitus amongst the high risk age group population in urban and rural areas of Kanpur.Study Design : Cross-sectional study.Setting : The study was performed on five thousand population each in urban and rural areas of Kanpur. Participants : High risk age group population i.e. 45 years and above.Study variables: Age, sex, education, working status, social class. Impaired glucose tolerance. Body mass index, Hypertension, family history of diabetes mellitus.Statistical analysis : Chi-square test. Percentages.Results : The overall prevalence of Diabetes mellitus amongst high risk age group population was found to be 7.6% with 11.3% in urban areas and 3.6% in rural areas. The overall maximum prevalence was in the 56-60 years age group. Higher prevalence was observed amongst the graduates and onwards (30.1%, social class-1 (32.1%, sedentary lifestyle (62.5%, obese (19.7%. hypertensives (39.5%, family history of diabetes mellitus (31.5%. It was observed that 77.7% cases in rural areas and 26.9% cases in urban areas were newly diagnosed.

  10. Youth as Design Partners: Age-Appropriate Websites for Middle and High School Students

    Science.gov (United States)

    Chow, Anthony S.; Smith, Kathelene McCarty; Sun, Katherine

    2012-01-01

    This study explored the impact of using best practices identified in previous studies in designing age-appropriate websites for middle and high school youth. Utilizing a mixed-method approach, 31 middle and 22 high school youth took part in six focus groups across four states. Participants were introduced to a website specifically designed for…

  11. Effect of thermal ageing on mechanical properties of a high-strength ODS alloy

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sung Hoon; Kim, Sung Hwan; Jang, Chang Heui [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Tae Kyu [Nuclear Materials DivisionKorea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    A new high-strength ODS alloy, ARROS, was recently developed for the application as the cladding material of a Sodium-cooled fast reactor (SFR). To assess the long-term integrity under thermal ageing, ARROS was thermally aged in air at 650°C for 1000 h. The degree of thermal ageing was assessed by mechanical tests such as uniaxial tensile, hardness, and small punch tests at from room temperature to 650°C. Tensile strength was slightly decreased but elongation, hardness, and small punch energy were hardly changed at all test temperatures for the specimen aged at 650°C for 1000 h. However, the variation in mechanical properties such as hardness and small punch energy increased after thermal ageing. Using the test results, the correlation between tensile strength and maximum small punch load was established.

  12. High repetition TEA CO2 laser with average output power of 3.3 kW%平均功率3.3kW高重复频率TEA CO2激光器

    Institute of Scientific and Technical Information of China (English)

    文康; 谭荣清; 张阔海; 刘世明; 朱玉峰; 徐程; 王东蕾; 卢远添; 赵志龙

    2011-01-01

    研制了一台平均功率3.3 kW横向激励大气压(TEA)CO2激光器.激光器采用单节放电体积为5 cm×4 cm×90 cm的两节腔体串连的形式,印刷板电路预电离结构和闸流管开关放电电路,实现了激光器单脉冲能量输出,高重复频率工作.在重复频率150 Hz条件下,获得了3.3 kW平均输出功率.获得32.8 J单脉冲输出能量,电光转换效率达到15.4%.%A high average power TEA CO2 laser has been developed. Average output power of 3.3 kW is achieved at a repetition of 150 Hz. The TEA CO2 laser consists of two same laser modules, each of which has a 5 cm x 4 cm× 90 cm discharge volume. Several special technologies including Printed Circuit Board (PCB) pre-ionization and thyratron switch discharging circuit are employed. The laser realized large energy output, high repetition operating and high average power output. Laser output pulse energy is measured. The relationship between laser pulse energy and voltage at different gas pressures is obtained. The maximum of output pulse energy is 32.8 J. Electro-optical efficiency is calculated and the maximum of electro-optical efficiency is 15.4%. The laser pulse waveforms are measured at different gas pressures.

  13. Pathway-Based Factor Analysis of Gene Expression Data Produces Highly Heritable Phenotypes That Associate with Age

    Science.gov (United States)

    Anand Brown, Andrew; Ding, Zhihao; Viñuela, Ana; Glass, Dan; Parts, Leopold; Spector, Tim; Winn, John; Durbin, Richard

    2015-01-01

    Statistical factor analysis methods have previously been used to remove noise components from high-dimensional data prior to genetic association mapping and, in a guided fashion, to summarize biologically relevant sources of variation. Here, we show how the derived factors summarizing pathway expression can be used to analyze the relationships between expression, heritability, and aging. We used skin gene expression data from 647 twins from the MuTHER Consortium and applied factor analysis to concisely summarize patterns of gene expression to remove broad confounding influences and to produce concise pathway-level phenotypes. We derived 930 “pathway phenotypes” that summarized patterns of variation across 186 KEGG pathways (five phenotypes per pathway). We identified 69 significant associations of age with phenotype from 57 distinct KEGG pathways at a stringent Bonferroni threshold (P<5.38×10−5). These phenotypes are more heritable (h2=0.32) than gene expression levels. On average, expression levels of 16% of genes within these pathways are associated with age. Several significant pathways relate to metabolizing sugars and fatty acids; others relate to insulin signaling. We have demonstrated that factor analysis methods combined with biological knowledge can produce more reliable phenotypes with less stochastic noise than the individual gene expression levels, which increases our power to discover biologically relevant associations. These phenotypes could also be applied to discover associations with other environmental factors. PMID:25758824

  14. Magnetic ageing study of high and medium permeability nanocrystalline FeSiCuNbB alloys

    Science.gov (United States)

    Lekdim, Atef; Morel, Laurent; Raulet, Marie-Ange

    2017-04-01

    increasing the energy efficiency is one of the most important issues in modern power electronic systems. In aircraft applications, the energy efficiency must be associated with a maximum reduction of mass and volume, so a high components compactness. A consequence from this compactness is the increase of operating temperature. Thus, the magnetic materials used in these applications, have to work at high temperature. It raises the question of the thermal ageing problem. The reliability of these components operating at this condition becomes a real problem which deserves serious interest. Our work takes part in this context by studying the magnetic material thermal ageing. The nanocrystalline materials are getting more and more used in power electronic applications. Main advantages of nanocrystalline materials compared to ferrite are: high saturation flux density of almost 1.25 T and low dynamic losses for low and medium frequencies. The nanocrystalline Fe73.5Cu1Nb3Si15.5B7 alloys have been chosen in our aging study. This study is based on monitoring the magnetic characteristics for several continuous thermal ageing (100, 150, 200 and 240 °C). An important experimental work of magnetic characterization is being done following a specific monitoring protocol. Elsewhere, X-Ray Diffraction and magnetostriction measurements were carried out to support the study of the anisotropy energies evolution with ageing. This latter is discussed in this paper to explain and give hypothesis about the ageing phenomena.

  15. FY2005 Progress Summary and FY2006 Program Plan Statement of Work and Deliverables for Development of High Average Power Diode-Pumped Solid State Lasers, and Complementary Technologies, for Applications in Energy and Defense

    Energy Technology Data Exchange (ETDEWEB)

    Ebbers, C

    2006-03-24

    The primary focus this year was to operate the system with two amplifiers populated with and pumped by eight high power diode arrays. The system was operated for extended run periods which enabled average power testing of components, diagnostics, and controls. These tests were highly successful, with a demonstrated energy level of over 55 joules for 4 cumulative hours at a repetition rate of 10 Hz (average power 0.55 kW). In addition, high average power second harmonic generation was demonstrated, achieving 227 W of 523.5 nm light (22.7 J, 10 Hz, 15 ns, 30 minutes) Plans to achieve higher energy levels and average powers are in progress. The dual amplifier system utilizes a 4-pass optical arrangement. The Yb:S-FAP slabs were mounted in aerodynamic aluminum vane structures to allow turbulent helium gas flow across the faces. Diagnostic packages that monitored beam performance were deployed during operation. The laser experiments involved injecting a seed beam from the front end into the system and making four passes through both amplifiers. Beam performance diagnostics monitored the beam on each pass to assess system parameters such as gain and nearfield intensity profiles. This year, an active mirror and wavefront sensor were procured and demonstrated in an off-line facility. The active mirror technology can correct for low order phase distortions at user specified operating conditions (such as repetition rates different than 10 Hz) and is a complementary technology to the static phase plates used in the system for higher order distortions. A picture of the laser system with amplifier No.2 (foreground) and amplifier No.1 (background) is shown in Fig. 1.0.1.1. The control system and diagnostics were recently enhanced for faster processing and allow remote operation of the system. The growth and fabrication of the Yb:S-FAP slabs constituted another major element of our program objectives. Our goal was to produce at least fourteen 4x6 cm2 crystalline slabs. These

  16. Vocal attractiveness increases by averaging.

    Science.gov (United States)

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception.

  17. High levels of mitochondrial DNA deletions in substantia nigra neurons in aging and Parkinson disease.

    Science.gov (United States)

    Bender, Andreas; Krishnan, Kim J; Morris, Christopher M; Taylor, Geoffrey A; Reeve, Amy K; Perry, Robert H; Jaros, Evelyn; Hersheson, Joshua S; Betts, Joanne; Klopstock, Thomas; Taylor, Robert W; Turnbull, Douglass M

    2006-05-01

    Here we show that in substantia nigra neurons from both aged controls and individuals with Parkinson disease, there is a high level of deleted mitochondrial DNA (mtDNA) (controls, 43.3% +/- 9.3%; individuals with Parkinson disease, 52.3% +/- 9.3%). These mtDNA mutations are somatic, with different clonally expanded deletions in individual cells, and high levels of these mutations are associated with respiratory chain deficiency. Our studies suggest that somatic mtDNA deletions are important in the selective neuronal loss observed in brain aging and in Parkinson disease.

  18. A New Type S-band High-average-power Broadband Klystron%一种新型S波段高平均功率宽带速调管

    Institute of Scientific and Technical Information of China (English)

    张兆传; 沈宝丽; 于晓娟; 张峰; 黄云平

    2011-01-01

    This paper presents the design considerations, the simulation results and the test results for a new type S-band high-average-power broadband klystron. In this paper, a method which is used for verifying the quality of an electron-optics-system of a high-average-power broadband klystron is proposed. And then the coordinate method using the 2.5D Arsenal-MSN code and the KLY6 code is also described, which deals with eliminating the potential output-power-sag and optimizing the parameters of the RF-interaction region for broadband klystrons. The further hot-test results prove that both of the methods are effective.%该文介绍了一种新型S波段高平均功率宽带速调管的主要设计思想、模拟计算结果和实验结果.文中提出了具有理想高频通过率的高平均功率宽带速调管电子光学系统的验证方法,以及联合使用2.5D Arsenal-MSN code和KLY6两种软件去除带内功率凹点和改善高频性能的方法.最终的实验测试结果表明,这些方法是有效的.

  19. High Aerobic Capacity Mitigates Changes in the Plasma Metabolomic Profile Associated with Aging.

    Science.gov (United States)

    Falegan, Oluyemi S; Vogel, Hans J; Hittel, Dustin S; Koch, Lauren G; Britton, Steven L; Hepple, Russ T; Shearer, Jane

    2017-02-03

    Advancing age is associated with declines in maximal oxygen consumption. Declines in aerobic capacity not only contribute to the aging process but also are an independent risk factor for morbidity, cardiovascular disease, and all-cause mortality. Although statistically convincing, the relationships between aerobic capacity, aging, and disease risk remain largely unresolved. To this end, we employed sensitive, system-based metabolomics approach to determine whether enhanced aerobic capacity could mitigate some of the changes seen in the plasma metabolomic profile associated with aging. Metabolomic profiles of plasma samples obtained from young (13 month) and old (26 month) rats bred for low (LCR) or high (HCR) running capacity using proton nuclear magnetic resonance spectroscopy ((1)H NMR) were examined. Results demonstrated strong profile separation in old and low aerobic capacity rats, whereas young and high aerobic capacity rat models were less predictive. Significantly differential metabolites between the groups include taurine, acetone, valine, and trimethylamine-N-oxide among other metabolites, specifically citrate, succinate, isovalerate, and proline, were differentially increased in older HCR animals compared with their younger counterparts. When interactions between age and aerobic capacity were examined, results demonstrated that enhanced aerobic capacity could mitigate some but not all age-associated alterations in the metabolomic profile.

  20. THE AGES OF HIGH-MASS X-RAY BINARIES IN NGC 2403 AND NGC 300

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Benjamin F.; Binder, Breanna A.; Dalcanton, Julianne J. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Eracleous, Michael [Department of Astronomy and Astrophysics and Center for Gravitational Wave Physics, Pennsylvania State University, 525 Davey Lab, University Park, PA 16803 (United States); Dolphin, Andrew, E-mail: ben@astro.washington.edu, E-mail: bbinder@astro.washington.edu, E-mail: jd@astro.washington.edu, E-mail: mce@astro.psu.edu, E-mail: adolphin@raytheon.com [Raytheon Company, Tucson, AZ 85734 (United States)

    2013-07-20

    We have examined resolved stellar photometry from HST imaging surrounding 18 high-mass X-ray binary (HMXB) candidates in NGC 300 and NGC 2403 as determined from combined Chandra/HST analysis. We have fit the color-magnitude distribution of the surrounding stars with stellar evolution models. All but one region in NGC 300 and two in NGC 2403 contain a population with an age between 20 and 70 Myr. One of the candidates is the ultraluminous X-ray source in NGC 2403, which we associate with a 60 {+-} 5 Myr old population. These age distributions provide additional evidence that 16 of these 18 candidates are HMXBs. Furthermore, our results suggest that the most common HMXB age in these galaxies is 40-55 Myr. This preferred age is similar to observations of HMXBs in the Small Magellanic Cloud, providing new evidence of this formation timescale, but in higher metallicity populations. We suggest that this preferred HMXB age is the result of the fortuitous combination of two physical effects. First, this is the age of a population when the greatest rate of core-collapse events should be occurring, maximizing neutron star production. Second, this is the age when B stars are most likely to be actively losing mass. We also discuss our results in the context of HMXB feedback in galaxies, confirming HMXBs as a potentially important source of energy for the interstellar medium in low-mass galaxies.

  1. Prediction of mortality at age 40 in Danish males at high and low risk for alcoholism

    DEFF Research Database (Denmark)

    Knop, J; Penick, E C; L Mortensen, E

    2004-01-01

    OBJECTIVE: This prospective high-risk study examined the influence of father's alcoholism and other archival-generated measures on premature death. METHOD: Sons of alcoholic fathers (n = 223) and sons of non-alcoholic fathers (n = 106) have been studied from birth to age 40. Archival predictors...... of premature death included father's alcoholism, childhood developmental data, and diagnostic information obtained from the Psychiatric Register and alcoholism clinics. RESULTS: By age 40, 21 of the 329 subjects had died (6.4%), a rate that is more than two times greater than expected. Sons of alcoholic...... fathers were not more likely to die by age 40. Premature death was associated with physical immaturity at 1-year of age and psychiatric/alcoholism treatment. No significant interactions were found between risk and archival measures. CONCLUSION: Genetic vulnerability did not independently predict death...

  2. Resolving high precision U-Pb ages from Tertiary plutons with complex zircon systematics

    Science.gov (United States)

    Mcclelland, William C.; Mattinson, James M.

    1996-10-01

    Success in establishing high precision crystallization ages with the U/Pb zircon method is highly dependent on the ability to isolate or remove the effects of inherited xenocrystic components or secondary lead-loss, or the combined effects of both. Current "conventional" single crystal and ion probe (SHRIMP) methods are successfully applied to Paleozoic and older samples but typically suffer from imprecision when applied to younger (Mesozoic-Cenozoic) samples due to generally reduced radiogenic lead concentrations. Here we apply a series of intense partial dissolution steps to multigrain zircon fractions from a series of Paleocene tonalitic to granodioritic intrusive rocks from southeastern Alaska. The zircon systematics are complicated by both minor inheritance and postcrystallization lead-loss. Physical and isotopic evidence demonstrate that the partial dissolution steps preferentially remove outer layers susceptible to lead loss, as well as core regions containing inherited components. The final residues are often hollow shells of low-U primary igneous zircon that yield highly precise, reproducible, and concordant ages. The resulting age determinations commonly statistically differ at the 95% confidence level from ages based on apparently concordant, but less precise conventional isotope dilution analyses, the uncertainties of which masked minor, subtle isotopic complexities. This observation strongly cautions against basing age assignments of samples yielding slightly discordant data on (1) single "concordant" analyses accompanied by an array of discordant data or (2) the mean of several 206Pb/ 238U or 207Pb/ 206Pb ages. The step-wise dissolution technique allows age determinations on young, relatively low U and Pb zircons at a resolution not currently possible with techniques such as single-grain conventional or spot ion probe analyses. Widespread application of the technique will likely prove instrumental in resolving detailed magmatic histories of igneous

  3. Ergodic averages via dominating processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Mengersen, Kerrie

    2006-01-01

    We show how the mean of a monotone function (defined on a state space equipped with a partial ordering) can be estimated, using ergodic averages calculated from upper and lower dominating processes of a stationary irreducible Markov chain. In particular, we do not need to simulate the stationary ...

  4. High serum coenzyme Q10, positively correlated with age, selenium and cholesterol in Inuit of Greenland

    DEFF Research Database (Denmark)

    Pedersen, Henning Sloth; Mortensen, S.A.; Rhode, M.

    1999-01-01

    .001) compared to a Danish population. In a linear multiple regression model the S-CoQ10 level is significantly positively associated with age and S-selenium in males, and S-total cholesterol in females. The high level of CoQ10 in Greenlanders probably reflects diet, since no bioaccumulation takes place...

  5. Early age stress-crack opening relationships for high performance concrete

    DEFF Research Database (Denmark)

    Østergaard, Lennart; Lange, David A.; Stang, Henrik

    2004-01-01

    Stress–crack opening relationships for concrete in early age have been determined for two high performance concrete mixes with water to cementitious materials ratios of 0.307 and 0.48. The wedge splitting test setup was used experimentally and the cracked nonlinear hinge model based on the fictit...

  6. Perception of Talker Age by Young Adults with High-Functioning Autism

    Science.gov (United States)

    Clopper, Cynthia G.; Rohrbeck, Kristin L.; Wagner, Laura

    2013-01-01

    People with high-functioning Autism (HFA) can accurately identify social categories from speech, but they have more difficulty connecting linguistic variation in the speech signal to social stereotypes associated with those categories. In the current study, the perception and evaluation of talker age by young adults with HFA was examined. The…

  7. Benchmarking statistical averaging of spectra with HULLAC

    Science.gov (United States)

    Klapisch, Marcel; Busquet, Michel

    2008-11-01

    Knowledge of radiative properties of hot plasmas is important for ICF, astrophysics, etc When mid-Z or high-Z elements are present, the spectra are so complex that one commonly uses statistically averaged description of atomic systems [1]. In a recent experiment on Fe[2], performed under controlled conditions, high resolution transmission spectra were obtained. The new version of HULLAC [3] allows the use of the same model with different levels of details/averaging. We will take advantage of this feature to check the effect of averaging with comparison with experiment. [1] A Bar-Shalom, J Oreg, and M Klapisch, J. Quant. Spectros. Rad. Transf. 65, 43 (2000). [2] J. E. Bailey, G. A. Rochau, C. A. Iglesias et al., Phys. Rev. Lett. 99, 265002-4 (2007). [3]. M. Klapisch, M. Busquet, and A. Bar-Shalom, AIP Conference Proceedings 926, 206-15 (2007).

  8. Emergent biomarkers of residual cardiovascular risk in patients with low HDL-c and/or high triglycerides and average LDL-c concentrations: focus on HDL subpopulations, Oxidized LDL, adiponectin, and uric acid.

    Science.gov (United States)

    Mascarenhas-Melo, Filipa; Palavra, Filipe; Marado, Daniela; Sereno, José; Teixeira-Lemos, Edite; Freitas, Isabel; Isabel-Mendonça, Maria; Pinto, Rui; Teixeira, Frederico; Reis, Flávio

    2013-01-01

    This study intended to determine the impact of HDL-c and/or TGs levels on patients with average LDL-c concentration, focusing on lipidic, oxidative, inflammatory, and angiogenic profiles. Patients with cardiovascular risk factors (n = 169) were divided into 4 subgroups, combining normal and low HDL-c with normal and high TGs patients. The following data was analyzed: BP, BMI, waist circumference and serum glucose, Total-c, TGs, LDL-c, oxidized-LDL, total HDL-c and HDL subpopulations, paraoxonase-1 (PON1) activity, hsCRP, uric acid, TNF- α , adiponectin, VEGF, and iCAM1. The two populations with increased TGs levels, regardless of the normal or low HDL-c, presented obesity and higher waist circumference, Total-c, LDL-c, Ox-LDL, and uric acid. Adiponectin concentration was significantly lower and VEGF was higher in the population with cumulative low values of HDL-c and high values of TGs, while HDL quality was reduced in the populations with impaired values of HDL-c and/or TGs, viewed by reduced large and increased small HDL subfractions. In conclusion, in a population with cardiovascular risk factors, low HDL-c and/or high TGs concentrations seem to be associated with a poor cardiometabolic profile, despite average LDL-c levels. This condition, often called residual risk, is better evidenced by using both traditional and nontraditional CV biomarkers, including large and small HDL subfractions, Ox-LDL, adiponectin, VEGF, and uric acid.

  9. Evolution of undissolved phases in high-zinc content super-high strength aluminum alloy during ageing

    Institute of Scientific and Technical Information of China (English)

    张坤; 刘志义; 叶呈武; 许晓嫦; 郑青春

    2004-01-01

    The evolution of undissolved phases in the high-zinc content super-high strength aluminum alloy during ageing was investigated by means of SEM and EIS. The results show that undissolved phases of Cu-rich M(AlZnMgCu) exist in the silver-free alloy at solid-solution state. With increasing the ageing time, the precipitation of agehardening precipitates MgZn2 stimulates Zn atoms within the undissolved phases to diffuse into the matrix, and thus the Cu content in the M(AlZnMgCu) phase increases relatively. For the silver-bearing alloy, small addition of Ag promotes the formation of Ag-rich M(A1ZnMgCuAg) undissolved phases and deteriorates mechanical properties of the alloy. At the early stage of ageing, Ag content within the M(AlZnMgCuAg) phases greatly decreases due to rapid diffusing of Ag atoms into the matrix and the co-clustering of Ag and Mg atoms. As the ageing time prolonging, the precipitation of MgZn2 results in the decrease of Zn content in the undissolved phases, and the relative increase of Ag and Mg contents.

  10. The Ages of High Mass X-ray Binaries in NGC 2403 and NGC 300

    CERN Document Server

    Williams, Benjamin F; Dalcanton, Julianne J; Eracleous, Michael; Dolphin, Andrew

    2013-01-01

    We have examined resolved stellar photometry from HST imaging surrounding 18 high-mass X-ray binary (HMXB) candidates in NGC 300 and NGC 2403 as determined from combined Chandra/HST analysis. We have fit the color-magnitude distribution of the surrounding stars with stellar evolution models. All but one region in NGC 300 and two in NGC 2403 contain a population with an age between 20 and 70 Myr. One of the candidates is the ultraluminous X-ray source (ULX) in NGC 2403, which we associate with a 60 Myr old population. These age distributions provide additional evidence that 16 of these 18 candidates are HMXBs. Furthermore, our results suggest that the most common HMXB age in these galaxies is 40-55 Myr. This preferred age is similar to observations of HMXBs in the Small Magellanic Cloud, providing new evidence of this formation timescale, but in higher metallicity populations. We suggest that this preferred HMXB age is the result of the fortuitous combination of two physical effects. First, this is the age of ...

  11. A new high-resolution seafloor age grid for the South Atlantic

    Science.gov (United States)

    Pérez-Díaz, L.; Eagles, G.

    2017-01-01

    Digital grids of basement age of the world's oceans are essential for modern geodynamic and paleoceanographic studies. Any such grid is built using a plate kinematic model, whose accuracy and reliability directly influence the accuracy and reliability of the grid. We present a seafloor age grid for the South Atlantic based on a recent high-resolution plate kinematic model. The grid is built from a data set of points whose ages are defined in or for the plate kinematic model, incorporating breaks at tectonic boundaries like fracture zones where the age function is discontinuous. We compare predictions of the new grid and of a previously published one, which is based on an older plate kinematic model, to magnetic isochron pick data sets. The comparison shows the new grid to provide a more reliable depiction of seafloor age in the South Atlantic. Numerical estimates of the new grid's uncertainty are determined by interpolation between (1) misfits at grid cells coinciding with magnetic isochron ages, (2) misfits implied by locational uncertainties in predicted isochrons propagated from uncertainties in the plate kinematic model, and (3) by the proximities of cells to fracture zone traces or ridge-jump scars. Estimated total uncertainty is Normal Superchron) and in the vicinity of long-offset fracture zones.

  12. Dependability in Aggregation by Averaging

    CERN Document Server

    Jesus, Paulo; Almeida, Paulo Sérgio

    2010-01-01

    Aggregation is an important building block of modern distributed applications, allowing the determination of meaningful properties (e.g. network size, total storage capacity, average load, majorities, etc.) that are used to direct the execution of the system. However, the majority of the existing aggregation algorithms exhibit relevant dependability issues, when prospecting their use in real application environments. In this paper, we reveal some dependability issues of aggregation algorithms based on iterative averaging techniques, giving some directions to solve them. This class of algorithms is considered robust (when compared to common tree-based approaches), being independent from the used routing topology and providing an aggregation result at all nodes. However, their robustness is strongly challenged and their correctness often compromised, when changing the assumptions of their working environment to more realistic ones. The correctness of this class of algorithms relies on the maintenance of a funda...

  13. Measuring Complexity through Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2015-01-01

    This work introduces a complexity measure which addresses some conflicting issues between existing ones by using a new principle - measuring the average amount of symmetry broken by an object. It attributes low (although different) complexity to either deterministic or random homogeneous densities and higher complexity to the intermediate cases. This new measure is easily computable, breaks the coarse graining paradigm and can be straightforwardly generalised, including to continuous cases an...

  14. Quantum Averaging of Squeezed States of Light

    DEFF Research Database (Denmark)

    Squeezing has been recognized as the main resource for quantum information processing and an important resource for beating classical detection strategies. It is therefore of high importance to reliably generate stable squeezing over longer periods of time. The averaging procedure for a single qu...

  15. Palaeoethnobotanical Data from the High Mountainous Early Bronze Age Settlement of Tsaghkasar-1 (Mt. Aragats, Armenia

    Directory of Open Access Journals (Sweden)

    Roman Hovsepyan

    2011-09-01

    Full Text Available Palaeoethnobotanical investigations suggest that at least part of the Early Bronze Age population of Tsaghkasar was settled and practiced agriculture in the high mountainous zone. People there appear to have cultivated hexa‐ and tetraploid wheats (probably bread wheat and emmer and barley (possibly hulled. Bronze Age agriculture in the Southern Caucasus differs from earlier and later period when cultivation of pulses, oil‐producing plants, and other plants was common. This emphasis on the cultivation and use of certain cereal grains at Early Bronze sites such as Tsaghkasar can tentatively be added to a constellation of practices associated with the Kura‐Araxes culture in the South Caucasus.

  16. Isotopic composition analysis and age dating of uranium samples by high resolution gamma ray spectrometry

    Science.gov (United States)

    Apostol, A. I.; Pantelica, A.; Sima, O.; Fugaru, V.

    2016-09-01

    Non-destructive methods were applied to determine the isotopic composition and the time elapsed since last chemical purification of nine uranium samples. The applied methods are based on measuring gamma and X radiations of uranium samples by high resolution low energy gamma spectrometric system with planar high purity germanium detector and low background gamma spectrometric system with coaxial high purity germanium detector. The "Multigroup γ-ray Analysis Method for Uranium" (MGAU) code was used for the precise determination of samples' isotopic composition. The age of the samples was determined from the isotopic ratio 214Bi/234U. This ratio was calculated from the analyzed spectra of each uranium sample, using relative detection efficiency. Special attention is paid to the coincidence summing corrections that have to be taken into account when performing this type of analysis. In addition, an alternative approach for the age determination using full energy peak efficiencies obtained by Monte Carlo simulations with the GESPECOR code is described.

  17. DEVELOPING OF HIGH QUALITY COURSE MATERIALS TO IMPROVE EARLY AGE PRACTITIONERS’ EDUCATION

    Directory of Open Access Journals (Sweden)

    MONA VINTILA

    2012-11-01

    Full Text Available The pre-primary age is an especially sensitive period in children’s development but high quality education and care from a very early age creates a good foundation for lifelong learning. This is why performant teacher education is needed.This paper addresses the issue of early age practitioners’ education presenting an European project that aims to develop course materials that focus on the major areas in early learning and contribute to the development of research based, pedagogical approaches within three areas that are crucial in respect to get all toddlers on a successful life learning road: learning of language(s and focus on the teacher-child communication, improved knowledge of how to foster toddlers'wellbeing, identifying crucial aspects for improved parental involvement.

  18. Influence of Trace Oxygen on the Mechanical Properties of High Pure Silver during Natural Aging

    Institute of Scientific and Technical Information of China (English)

    XIE Hongchao; ZHUANG Dianxiang; LI Ji; CHEN Liangwei; YANG Anheng; LUO Yanbo; ZHU Yong

    2012-01-01

    Two kinds of high pure silver materials with 5.3 ppm oxygen and 32.7 ppm oxygen were prepared by various melting processes,both samples were subjected to accumulative rolling with 95% thickness reduction.Their mechanical properties were tested during long natural aging.Results showed that the Ag sheet with 5.3 ppm oxygen is at full annealed state when natural aging 58 days or kept at 150℃ for 30 minutes,and the Ag sheet with 32.7 ppm oxygen is a little of recovery when natural aging a year.It is suggested that appropriate oxygen interstitial solute in Ag solid solution and a few of Ag2O particles at Ag grain boundaries impede the recovery and recrystallization of Ag sheets.

  19. FY2002 Progress Summary Program Plan, Statement of Work and Deliverables for Development of High Average Power Diode-Pumped Solid State Lasers, and Complementary Technologies, for Applications in Energy and Defense

    Energy Technology Data Exchange (ETDEWEB)

    Bayramian, A; Bibeau, C; Beach, R; Behrendt, B; Ebbers, C; Latkowski, J; Meier, W; Payne, S; Perkins, J; Schaffers, K; Skulina, K; Ditmire, T; Kelly, J; Waxer, L; Rudi, P; Randles, M; Witter, D; Meissner, H; Merissner, O

    2001-12-13

    The High Average Power Laser Program (HAPL) is a multi-institutional, coordinated effort to develop a high-energy, repetitively pulsed laser system for Inertial Fusion Energy and other DOE and DOD applications. This program is building a laser-fusion energy base to complement the laser-fusion science developed by DOE Defense programs over the past 25 years. The primary institutions responsible for overseeing and coordinating the research activities are the Naval Research Laboratory (NRL) and LLNL. The current LLNL proposal is a companion proposal to that submitted by NRL, for which the driver development element is focused on the krypton fluoride excimer laser option. Aside from the driver development aspect, the NRL and LLNL companion proposals pursue complementary activities with the associated rep-rated laser technologies relating to target fabrication, target injection, final optics, fusion chamber, materials and power plant economics. This report requests continued funding in FY02 to support LLNL in its program to build a 1kW, 100J, diode-pumped, crystalline laser. In addition, research in high gain laser target design, fusion chamber issues and survivability of the final optic element will be pursued. These technologies are crucial to the feasibility of inertial fusion energy power plants and also have relevance in rep-rated stewardship experiments.

  20. Highly Reproducible Perovskite Solar Cells with Average Efficiency of 18.3% and Best Efficiency of 19.7% Fabricated via Lewis Base Adduct of Lead(II) Iodide.

    Science.gov (United States)

    Ahn, Namyoung; Son, Dae-Yong; Jang, In-Hyuk; Kang, Seong Min; Choi, Mansoo; Park, Nam-Gyu

    2015-07-15

    High efficiency perovskite solar cells were fabricated reproducibly via Lewis base adduct of lead(II) iodide. PbI2 was dissolved in N,N-dimethyformamide with equimolar N,N-dimethyl sulfoxide (DMSO) and CH3NH3I. Stretching vibration of S═O appeared at 1045 cm(-1) for bare DMSO, which was shifted to 1020 and 1015 cm(-1) upon reacting DMSO with PbI2 and PbI2 + CH3NH3I, respectively, indicative of forming the adduct of PbI2·DMSO and CH3NH3I·PbI2·DMSO due to interaction between Lewis base DMSO and/or iodide (I(-)) and Lewis acid PbI2. Spin-coating of a DMF solution containing PbI2, CH3NH3I, and DMSO (1:1:1 mol %) formed a transparent adduct film, which was converted to a dark brown film upon heating at low temperature of 65 °C for 1 min due to removal of the volatile DMSO from the adduct. The adduct-induced CH3NH3PbI3 exhibited high charge extraction characteristics with hole mobility as high as 3.9 × 10(-3) cm(2)/(V s) and slow recombination rate. Average power conversion efficiency (PCE) of 18.3% was achieved from 41 cells and the best PCE of 19.7% was attained via adduct approach.

  1. Early Signs of Pathological Cognitive Aging in Mice Lacking High-Affinity Nicotinic Receptors.

    Science.gov (United States)

    Konsolaki, Eleni; Tsakanikas, Panagiotis; Polissidis, Alexia V; Stamatakis, Antonios; Skaliora, Irini

    2016-01-01

    In order to address pathological cognitive decline effectively, it is critical to adopt early preventive measures in individuals considered at risk. It is therefore essential to develop approaches that identify such individuals before the onset of irreversible dementia. A deficient cholinergic system has been consistently implicated as one of the main factors associated with a heightened vulnerability to the aging process. In the present study we used mice lacking high affinity nicotinic receptors (β2-/-), which have been proposed as an animal model of accelerated/premature cognitive aging. Our aim was to identify behavioral signs that could serve as indicators or predictors of impending cognitive decline. We used test batteries in order to assess cognitive functions and additional tasks to investigate spontaneous behaviors, such as species-specific activities and exploration/locomotion in a novel environment. Our data confirm the hypothesis that β2-/- animals exhibit age-related cognitive impairments in spatial learning. In addition, they document age-related deficits in other areas, such as recognition memory, burrowing and nesting building, thereby extending the validity of this animal model for the study of pathological aging. Finally, our data reveal deficits in spontaneous behavior and habituation processes that precede the onset of cognitive decline and could therefore be useful as a non-invasive behavioral screen for identifying animals at risk. To our knowledge, this is the first study to perform an extensive behavioral assessment of an animal model of premature cognitive aging, and our results suggest that β2-nAChR dependent cognitive deterioration progressively evolves from initial subtle behavioral changes to global dementia due to the combined effect of the neuropathology and aging.

  2. Age-related differences in repeated-sprint ability in highly trained youth football players.

    Science.gov (United States)

    Mujika, Inigo; Spencer, Matt; Santisteban, Juanma; Goiriena, Juan Jose; Bishop, David

    2009-12-01

    In this study, we investigated the age-related differences in repeated-sprint ability and blood lactate responses in 134 youth football players. Players from the development programme of a professional club were grouped according to their respective under-age team (U-11 to U-18). Following familiarization, the participants performed a repeated-sprint ability test [6 x 30-m sprints 30 s apart, with active recovery (2.0-2.2 m . s(-1)) between sprints]. The test variables were total time, percent sprint decrement, and post-test peak lactate concentration. Total time improved from the U-11 to U-15 age groups (range 33.15 +/- 1.84 vs. 27.25 +/- 0.82 s), whereas no further significant improvements were evident from U-15 to U-18. No significant differences in percent sprint decrement were reported among groups (range 4.0 +/- 1.0% to 5.5 +/- 2.1%). Post-test peak lactate increased from one age group to the next (range 7.3 +/- 1.8 to 12.6 +/- 1.6 mmol . l(-1)), but remained constant when adjusted for age-related difference in body mass. Peak lactate concentration was moderately correlated with sprint time (r = 0.70, P > 0.001). Our results suggest that performance in repeated-sprint ability improves during maturation of highly trained youth football players, although a plateau occurs from 15 years of age. In contrast to expectations based on previous suggestions, percent sprint decrement during repeated sprints did not deteriorate with age.

  3. Risk factors for high blood pressure in low income children aged 3-4 years.

    Science.gov (United States)

    Vitolo, Márcia Regina; da Costa Louzada, Maria Laura; Rauber, Fernanda; Campagnolo, Paula Dal Bó

    2013-08-01

    This study aimed to evaluate the effect of dietary sodium intake on blood pressure among low income children aged 3-4 years. Data were collected during a randomized trial conducted in São Leopoldo, Brazil, with 500 mother-child pairs recruited from the maternity ward of a local hospital. Breastfeeding data were obtained during the children's first year of life. At 3 to 4 years of age, children's anthropometric, dietary, and blood pressure assessments were obtained. Sodium intake was estimated from two multiple-pass 24-h dietary recalls. Systolic blood pressure > 90th percentile for age, sex, and height was classified as high systolic blood pressure, according to the population-based percentiles provided by the Task Force on Hypertension Control in Children and Adolescents. Blood pressure data were obtained from 331 children at 3 to 4 years. The mean value of systolic blood pressure was 91.31 mmHg (SD = 8.30 mmHg) and 5.2% (n = 17) presented high systolic blood pressure. The results of the multivariable analyses showed that children who consumed more than 1,200 mg of sodium/day and with waist-to-height ratio higher than 0.5 presented, respectively, 3.32 (95%CI 0.98-11.22) and 8.81 (95%CI 2.13-36.31) greater risk of having high systolic blood pressure. Exclusive breastfeeding, child overweight and change in body mass index z score during the first year of life were not associated with the outcome. The results of this study suggest that at preschool age sodium intake and high waist-to-height ratio are risk factors for high systolic blood pressure.

  4. Early signs of pathological cognitive aging in mice lacking high-affinity nicotinic receptors.

    Directory of Open Access Journals (Sweden)

    Eleni eKonsolaki

    2016-04-01

    Full Text Available In order to address pathological cognitive decline effectively, it is critical to adopt early preventive measures in individuals considered at risk. It is therefore essential to develop approaches that identify such individuals before the onset of irreversible dementia. Α deficient cholinergic system has been consistently implicated as one of the main factors associated with a heightened vulnerability to the aging process. In the present study we used mice lacking high affinity nicotinic receptors (β2-/-, which have been proposed as an animal model of accelerated/premature cognitive aging. Our aim was to identify behavioural signs that could serve as indicators or predictors of impending cognitive decline. We used test batteries in order to assess cognitive functions and additional tasks to investigate spontaneous behaviours, such as species-specific activities and exploration/locomotion in a novel environment. Our data confirm and extend the hypothesis that β2-/- animals exhibit age-related cognitive impairments, manifested in both spatial learning and recognition memory tasks. In addition, we reveal deficits in spontaneous behaviour and habituation processes earlier in life. To our knowledge, this is the first study to perform an extensive behavioural examination of an animal model of premature cognitive aging, and our results suggest that β2-nAChR dependent cognitive deterioration progressively evolves from initial subtle behavioural changes to global dementia due to the combined effect of the neuropathology and aging.

  5. Hormone-sensitive lipase-knockout mice maintain high bone density during aging.

    Science.gov (United States)

    Shen, Wen-Jun; Liu, Li-Fen; Patel, Shailja; Kraemer, Fredric B

    2011-08-01

    We tested the hypothesis that the actions of hormone-sensitive lipase (HSL) affect the microenvironment of the bone marrow and that removal of HSL function by gene deletion maintains high bone mass in aging mice. We compared littermate control wild-type (WT) and HSL(-/-) mice during aging for changes in serum biochemical values, trabecular bone density using micro-computed tomography, bone histomorphometry, and characteristics of primary bone marrow cells and preosteoblasts. There is a regulated expression of HSL and genes involved in lipid metabolism in the bone marrow during aging. HSL(-/-) mice have increased serum levels of insulin and osteocalcin with decreased leptin levels. Compared with the marked adipocyte infiltration in WT bone marrow (65% by area) at 14 mo, HSL(-/-) mice have fewer (16%, PHSL(-/-) mice maintain a higher bone density (bone volume/total volume 6.1%) with age than WT mice (2.6%, PHSL(-/-) mice show increased growth rates and higher osteogenic potential, manifested by increased expression of Runx2 (3.5-fold, PHSL directs cells within the bone marrow toward osteoblast differentiation and favors the maintenance of bone density with aging.

  6. New high-precision 40Ar/39Ar ages on Oligocene volcanic rocks of northwestern Kenya

    Science.gov (United States)

    Brown, Francis H.; Jicha, Brian R.

    2016-02-01

    New, high-precision 40Ar/39Ar ages from volcanic rocks in northwestern Kenya are provided for some areas of exposure in this remote area. We report seven 40Ar/39Ar ages generated from single crystal total fusion experiments on alkali feldspar separated from volcanic rocks in the Mogila, Songot, and Lokwanamur Ranges and the Gatome valley. A rhyolite from the lower part of the sequence in the Mogila Range yielded ages of 32.31 ± 0.06 Ma and 32.33 ± 0.07 Ma, and a rhyolite near the top of that sequence yielded 31.67 ± 0.04 Ma. A single sample from the Songot Range yielded an age of 32.49 ± 0.07 Ma, slightly older than the rocks collected from Mogila. In both ranges the early Oligocene rhyolites are underlain by basalts, as is also the case in the Labur Range. Ages of 25.95 ± 0.03 Ma, 25.91 ± 0.04 Ma, and 27.15 ± 0.03 Ma were measured on alkali feldspar from rhyolites from the Lokwanamur Range, and the nearby Gatome valley. All of these rocks are part of an episode of widespread volcanism in northwestern Kenya in the mid-to late Oligocene that is not currently known from the Ethiopian Rift Valley.

  7. Serotonin mediates a learned increase in attraction to high concentrations of benzaldehyde in aged C. elegans.

    Science.gov (United States)

    Tsui, David; van der Kooy, Derek

    2008-11-01

    We utilized olfactory-mediated chemotaxis in Caenorhabditis elegans to examine the effect of aging on information processing and animal behavior. Wild-type (N2) young adults (day 4) initially approach and eventually avoid a point source of benzaldehyde. Aged adult animals (day 7) showed a stronger initial approach and a delayed avoidance to benzaldehyde compared with young adults. This delayed avoidance is due to an increased attraction rather than a decreased avoidance to benzaldehyde because (1) aged odr-3 mutants that are defective in odor attraction showed no delayed benzaldehyde avoidance, and (2) the delay in avoidance was also observed with another attractant diacetyl, but not the repellent octanol. Interestingly, the stronger expression of attractive behavior was only observed at benzaldehyde concentrations of 1% or higher. When worms were grown on nonbacterial growth media instead of Escherichia coli, thus removing the contingency between odors released from the food and the food itself, the increase in attraction to benzaldehyde disappeared. The increased attraction recovered after reinitiating the odor-food contingency by returning animals to E. coli food or supplementing axenic media with benzaldehyde. Moreover, serotonin-deficient mutants showed a deficit in the age-enhanced attraction. These results suggest that the increased attraction to benzaldehyde in aged worms is (1) serotonin mediated, (2) specific to high concentration of odorants, and (3) dependent on a learned association of odor metabolites with the presence of food. We propose that associative learning may selectively modify pathways at or downstream from a low-affinity olfactory receptor.

  8. Mirror averaging with sparsity priors

    CERN Document Server

    Dalalyan, Arnak

    2010-01-01

    We consider the problem of aggregating the elements of a (possibly infinite) dictionary for building a decision procedure, that aims at minimizing a given criterion. Along with the dictionary, an independent identically distributed training sample is available, on which the performance of a given procedure can be tested. In a fairly general set-up, we establish an oracle inequality for the Mirror Averaging aggregate based on any prior distribution. This oracle inequality is applied in the context of sparse coding for different problems of statistics and machine learning such as regression, density estimation and binary classification.

  9. Trends in birth across high-parity groups by race/ethnicity and maternal age.

    Science.gov (United States)

    Aliyu, Muktar H; Salihu, Hamisu M; Keith, Louis G; Ehiri, John E; Islam, M Aminul; Jolly, Pauline E

    2005-06-01

    The changing racial and ethnic diversity of the U.S. population along with delayed childbearing suggest that shifts in the demographic composition of gravidas are likely. It is unclear whether trends in the proportion of births to parous women in the United States have changed over the decades by race and ethnicity, reflecting parallel changes in population demographics. Singleton deliveries > or = 20 weeks of gestation in the United States from 1989 through 2000 were analyzed using data from the "Natality data files" assembled by the National Center for Health Statistics (NCHS). We classified maternal age into three categories; younger mothers (aged or = 40 years) and maternal race/ethnicity into three groups: blacks (non-Hispanic), Hispanics and whites (non-Hispanic). We computed birth rates by period of delivery across the entire population and repeated the analysis stratified by age and maternal race. Chi-squared statistics for linear trend were utilized to assess linear trend across three four-year phases: 1989-1992, 1993-1996 and 1997-2000. In estimating the association between race/ethnicity and parity status, the direct method of standardization was employed to adjust for maternal age. Over the study period, the total number of births to blacks and whites diminished consistently (p for trend fashion among the high (5-9 previous live births), very high (10-14 previous live births) and extremely high (> or = 15 previous live births) parity groups (p for trend < 0.001). After maternal age standardization, black and Hispanic women were more likely to have higher parity as compared to whites. Our findings demonstrate substantial variation in parity patterns among the main racial and ethnic populations in the United States. These results may help in formulating strategies that will serve as templates for optimizing resource allocation across the different racial/ethnic subpopulations in the United States.

  10. [Analysis on geographic distribution of high blood pressure prevalence in children and adolescents aged 7-18 years in China, 2014].

    Science.gov (United States)

    Dong, Y H; Zou, Z Y; Wang, Z H; Wang, S; Yang, Z P; Chen, Y J; Ma, J

    2017-07-10

    Objective: To understand and evaluate the characteristics of geographic distribution of high blood pressure prevalence in children and adolescents aged 7-18 years in China in 2014, and provide evidence for the prevention of hypertension in children and adolescents. Methods: The data of 2014 Chinese National Surveys on Students Constitution and Health conducting 31 provinces (except Hong Kong, Macao and Taiwan) were collected. A total of 216 299 children and adolescents who had complete blood pressure records were selected as study subjects. The low, middle and high prevalence areas were identified according to their high blood pressure detection rates in the children and adolescents,7%, to analyze the geographic distribution of high blood pressure prevalence in the children and adolescents. The environmental data in the capitals of 31 provinces in 2014 were collected to analyze the correlation between environmental factors and blood pressure Z score in the children and adolescents. Results: The average detection rates of high blood pressure was 6.4% in 31 provinces (1.5%-14.2%). The high prevalence areas were mainly distributed in the eastern China, especially the Circum-Bohai sea area, low prevalence areas were mainly distributed in the central and western areas of China and some provinces in the east. Correlation analysis results showed that the annual average temperature, annual average air humidity and local altitude were negatively correlated with blood pressure Z score, including diastolic and systolic blood pressure, in both boys and girls. The annual average sunshine time, PM(2.5) and PM(10) concentrations, content of SO(2) were positively correlated with blood pressure Z score in both boys and girls. Conclusions: There was a significant difference in high blood pressure of children and adolescents among 31 provinces. More attention should be paid to the children and adolescents living high prevalence area. And it is necessary to understand environmental

  11. Tamanho da leitegada e pesos médios, ao nascer e aos 21 dias de idade, de leitões da raça Large White Litter size and average weights at birth and at 21 days of age of Large White piglets

    Directory of Open Access Journals (Sweden)

    M.C.R. Holanda

    2005-08-01

    Full Text Available Avaliaram-se os efeitos da época de parto e idade da matriz ao parto (IMP sobre o tamanho da leitegada (TL, da época de parto, idade da matriz ao parto e tamanho da leitegada sobre o peso médio ao nascer (PMN, e da época de parto, idade da matriz ao parto, número de nascidos vivos (NV e percentual de machos na leitegada (PERCM sobre o peso aos 21 dias de idade (PM21 de leitões Large White. Utilizaram-se dados de 3259 leitões nascidos no período de junho/85 a junho/96. A avaliação foi feita por meio de regressão múltipla. Para TL apenas o efeito de IMP determinou modificações significativas sobre o número de leitões nascidos. TL médio foi 9,73±2,78, observando-se maiores leitegadas em fêmeas de 2,84 a 3,83 anos. PMN e PM21 foram 1,35kg±0,18 e 5,06kg±1,00, respectivamente. Para PMN foram significativos os efeitos de IMP e TL, com redução do peso em 20g para cada leitão adicional. Para PM21 apenas o número de NV apresentou efeito significativo.The effects of season of birth (PE and age of sow at birth (IMP on litter size (TL; season of birth, age of sow and litter size on average weight at birth (PMN; season of birth age of sow, number of alive piglets at birth (NV, and percentage of alive males on average weight at 21 days of age (PM21 of 3259 Large White piglets born from June/85 to June/96 were evaluated by multiple regression analyses. The IMP effect on TL was significant. The average TL was 9.73±2.78. Larger litters were observed for sows from 2.84 to 3.83 years of age. The average PMN and PM21 were 1.35kg±0.18 e 5.06kg±1.00, respectively. The IMP and TL effects on PMN traits were linear and significant. A decrease of 20g on piglet weight was estimated for each additional piglet in the litter. The effect of NV was significant only for PM21 trait.

  12. A study of brainstem evoked response audiometry in high-risk infants and children under 10 years of age

    Directory of Open Access Journals (Sweden)

    Ramanathan Thirunavukarasu

    2015-01-01

    Full Text Available Aims: To evaluate the hearing threshold and find the incidence of hearing loss in infants and children belonging to high-risk category and analyze the common risk factors. Subjects and Methods: Totally, 125 infants and children belonging to high-risk category were subjected to brainstem evoked response audiometry. Clicks were given at the rate of 11.1 clicks/s. Totally, 2000 responses were averaged. The intensity at which wave V just disappears was established as hearing the threshold. Degree of impairment and risk factors were analyzed. Results: Totally, 44 (35.2% were found to have sensorineural hearing loss. Totally, 30 children with hearing loss (68% belonged to age group 1-5 years. Consanguineous marriage was the most commonly associated risk factor. Majority (34 had profound hearing loss. Conclusion: Newborn screening is mandatory to identify hearing loss in the prelinguistic period to reduce the burden of handicap in the community. The need of the hour is health education and genetic counseling to decrease the hereditary hearing loss, as hearing impairment due to perinatal factors has reduced due to recent medical advancements.

  13. High irradiation and ageing properties of resistive Micromegas detectors at the new CERN Gamma Irradiation Facility

    CERN Document Server

    Andreou, Dimitra

    2016-01-01

    Resistive Micromegas have been developed in recent years with the aim of making this technology usable in HEP experiments where the high sparking rate of classical Micromegas is not tolerable. A resistive Micromegas with four layers and an active surface of 0.5 m2 each, has been designed and built at CERN as prototype of the detectors to be used for the upgrade of the ATLAS experiment. The detector has been exposed to an intense gamma source of 16 TBq in order to study the effects of ageing and evaluate the detector behavior under high irradiation.

  14. Aging Behavior of High-Strength Al Alloy 2618 Produced by Selective Laser Melting

    Science.gov (United States)

    Casati, Riccardo; Lemke, Jannis Nicolas; Alarcon, Adrianni Zanatta; Vedani, Maurizio

    2017-02-01

    High Si-bearing Al alloys are commonly used in additive manufacturing, but they have moderate mechanical properties. New high-strength compositions are necessary to spread the use of additively manufactured Al parts for heavy-duty structural applications. This work focuses on the microstructure, mechanical behavior, and aging response of an Al alloy 2618 processed by selective laser melting. Calorimetric analysis, electron microscopy, and compression tests were performed in order to correlate the mechanical properties with the peculiar microstructure induced by laser melting and thermal treatments

  15. Assessment of peritrochanteric high T2 signal depending on the age and gender of the patients

    Energy Technology Data Exchange (ETDEWEB)

    Haliloglu, Nuray, E-mail: nurayunsal2@hotmail.co [Ankara University School of Medicine, Department of Radiology (Turkey); Inceoglu, Deniz; Sahin, Gulden [Ankara University School of Medicine, Department of Radiology (Turkey)

    2010-07-15

    Introduction: The aim of this study is to evaluate the incidence of peritrochanteric high T2 signal (peritrochanteric edema, peritendinitis) on routine MR imaging studies and to determine whether reporting peritrochanteric edema is always clinically relevant depending on the age and gender of the patients. Materials and methods: We evaluated 79 consecutive bilateral hip MR images performed in our department between January 2006 and December 2006 (57 female, 22 male patients, mean age 49 years). Each study was evaluated for areas of T2 hyperintensity representing edema around the greater trochanter. Patients with a known fracture, tumor, history of radiation therapy, history of hip surgery and prothesis were excluded from the study. Patients with signal intensity alterations within the thickened gluteus medius/minimus tendons (tendinitis) or peritrochanteric bursal fluid accumulation (bursitis) were also excluded. All patients were scanned with our routine MR imaging protocol for hip imaging. Results: In 55 of the 79 patients (70%) peritrochanteric edema was detected on MR images and 52 of these 55 patients (95%) had these changes on both hips. The median age was 56 years for the patients with peritrochanteric edema and 35.5 years for the patients without peritrochanteric edema. There was statistical significance between the median ages of the patients and a significant increased risk of peritrochanteric edema was found over 40 years of age. There was no significant difference between male and female patients. Conclusion: Bilateral peritrochanteric high T2 signal may be a part of the degeneration process and we suggest that it may not be necessarily reported if the clinical findings do not support greater trochanteric pain syndrome.

  16. Linking high-frequency DOC dynamics to the age of connected water sources

    Science.gov (United States)

    Tunaley, C.; Tetzlaff, D.; Lessels, J.; Soulsby, C.

    2016-07-01

    We combined high-frequency dissolved organic matter fluorescence (FDOM) data with stable isotope observations to identify the sources and ages of runoff that cause temporal variability in dissolved organic carbon (DOC) within a peat-dominated Scottish catchment. FDOM was strongly correlated (r2 ˜ 0.8) with DOC, allowing inference of a 15 min time series. We captured 34 events over a range of hydrological conditions. Along with marked seasonality, different event responses were observed during summer depending on dry or wet antecedent conditions. The majority of events exhibited anticlockwise hysteresis as a result of the expansion of the riparian saturation zone, mobilizing previously unconnected DOC sources. Water ages from the main runoff sources were extracted from a tracer-aided hydrological model. Particularly useful were ages of overland flow, which were negatively correlated with DOC concentration. Overland flow age, which ranged between 0.2 and 360 days, reflected antecedent conditions, with younger water generally mobilizing the highest DOC concentrations in summer events. During small events with dry antecedent conditions, DOC response was proportionally higher due to the displacement and mixing of small volumes of previously unconnected highly concentrated riparian soil waters by new precipitation. During large events with wet antecedent conditions, the riparian saturation zone expands to organic layers on the hillslopes causing peaks in DOC. However, these peaks were limited by dilution and supply. This study highlights the utility of linking high-frequency DOC measurements with other tracers, allowing the effects of hydrologic connectivity and antecedent conditions on delivery of DOC to streams to be assessed.

  17. Assessment of early-age cracking of high-performance concrete in restrained ring specimens

    Directory of Open Access Journals (Sweden)

    Quang-phu NGUYEN NGUYEN

    2010-03-01

    Full Text Available High-performance concrete (HPC is stronger and more durable than conventional concrete. However, shrinkage and shrinkage cracking are common phenomena in HPC, especially early-age cracking. This study assessed early-age cracking of HPC for two mixtures using restrained ring tests. The two mixtures were produced with water/binder mass ratio (mW/mB of 0.22 and 0.40, respectively. The results show that, with greater steel thickness, the higher degree of restraint resulted in a higher interface pressure and earlier cracking. With steel thickness of 6 mm, 19 mm, and 30 mm, the age of cracking were, respectively, 12 days, 8 days, and 5.4 days with the mW/mB = 0.22 mixture; and 22.5 days, 12.6 days, and 7.1 days with the mW/mB = 0.40 mixture. Cases of the same steel thickness show that the ring specimens with a thicker concrete wall crack later. With the mW/mB = 0.22 mixture, concrete walls with thicknesses of 37.5 mm, 75 mm, and 112.5 mm cracked at 3.4 days, 8.0 days, and 9.8 days, respectively; with the mW/mB = 0.40 mixture, the ages of cracking were 7.1 days, 12.6 days, and 16.0 days, respectively.

  18. 11~14岁超常儿童与普通儿童问题解决能力的发展比较%The Developmental Differences of Problem Solving Ability between Intellectually-gifted and Intellectually-average Children Aged from 11-14 Years Old

    Institute of Scientific and Technical Information of China (English)

    张博; 黎坚; 徐楚; 李一茗

    2014-01-01

    以北京市某中学和某小学11~14岁之间294名学生为被试,其中超常儿童131人,普通儿童163人。采用推箱子任务,结合横断比较和纵向追踪数据,从认知能力、元认知能力和认知效率三个维度来考察超常儿童与普通儿童问题解决能力的发展差异。结果发现超常儿童在问题解决能力的三个维度上均优于普通儿童,两类儿童问题解决能力的发展模式不一致:超常儿童的问题解决能力发展先快后慢,快速发展期在11~12岁半之间;普通儿童的问题解决能力发展先慢后快,快速发展期在12岁半~14岁之间。超常儿童与普通儿童的问题解决能力差异随年龄增大逐渐减小。%Problems are everywhere in daily life. The ability to solve problems helps human being survive natural selection, characterizing us as an intellectual species. It is also closely related to various life outcomes. A number of cross-sectional studies have demonstrated that intellectually-gifted children performed better than their average cohorts in problem solving tasks. But most of these studies primarily focus on the cognitive dimension of problem solving. They did not suffice to draw a whole picture of human problem solving ability. Moreover, few studies have explored the group differences from a developmental perspective, such as their developmental patterns or developmental critical stage, which could contribute a lot to both theories and educational practices. The present study investigated the developmental differences of problem solving ability between intellectually-gifted and intellectually-average children from cognitive, metacognitive and efficiency dimensions. Both cross-sectional and longitudinal data were collected. The cross-sectional study included 131 intellectually-gifted and 163 intellectually-average children aged from 11 to14, and the longitudinal study included 32 intellectually-gifted and 38 intellectually-average children

  19. Effects of High-Humidity Aging on Platinum, Palladium, and Gold Loaded Tin Oxide—Volatile Organic Compound Sensors

    Directory of Open Access Journals (Sweden)

    Maiko Nishibori

    2010-07-01

    Full Text Available This study is an investigation of high-humidity aging effects on the total volatile organic compound (T–VOC gas-sensing properties of platinum, palladium, and gold-loaded tin oxide (Pt,Pd,Au/SnO2 thick films. The sensor responses of the high-humidity aged Pt,Pd,Au/SnO2, a non-aged Pt,Pd,Au/SnO2, and a high-humidity aged Pt/SnO2 to T–VOC test gas have been measured. The high-humidity aging is an effective treatment for resistance to humidity change for the Pt,Pd,Au/SnO2 but not effective for the Pt/SnO2. The mechanism of the high-humidity aging effects is discussed based on the change of surface state of the SnO2 particles.

  20. Motivating Factors and Potential Deterrents to Blood Donation in High School Aged Blood Donors

    Directory of Open Access Journals (Sweden)

    Rachel Finck

    2016-01-01

    Full Text Available Background. To ensure an adequate supply of blood, collection centers must design campaigns that successfully recruit and maintain an active donor pool. Understanding factors that motivate and deter individuals from donating may help centers develop targeted recruitment campaigns. These factors among high school aged blood donors have not yet been fully investigated. Study Design and Methods. A voluntary, anonymous survey was administered to student donors at high school mobile blood drives. The survey instrument asked the students to rate several potential motivating factors in their importance in the decision to donate blood and several potential deterring factors in their future decision whether or not to donate blood again. The survey also asked the students to rate the desirability of several potential incentives. Results. Motivating factors that reflected prosocial, empathetic, and altruistic thoughts and beliefs were rated highly by students. Pain from phlebotomy was most commonly chosen as potential deterrent. Movie tickets and cookies/snacks at the drive were rated as the most attractive incentives. Conclusion. High school aged blood donors are similar to other donor groups in their expressed motives for donating blood. This group may be unique in the factors that deter them from donating and in their preferences for different incentives.

  1. Average Light Intensity Inside a Photobioreactor

    Directory of Open Access Journals (Sweden)

    Herby Jean

    2011-01-01

    Full Text Available For energy production, microalgae are one of the few alternatives with high potential. Similar to plants, algae require energy acquired from light sources to grow. This project uses calculus to determine the light intensity inside of a photobioreactor filled with algae. Under preset conditions along with estimated values, we applied Lambert-Beer's law to formulate an equation to calculate how much light intensity escapes a photobioreactor and determine the average light intensity that was present inside the reactor.

  2. The average visual response in patients with cerebrovascular disease

    NARCIS (Netherlands)

    Oostehuis, H.J.G.H.; Ponsen, E.J.; Jonkman, E.J.; Magnus, O.

    1969-01-01

    The average visual response (AVR) was recorded in thirty patients after a cerebrovascular accident and in fourteen control subjects from the same age group. The AVR was obtained with the aid of a 16-channel EEG machine, a Computer of Average Transients and a tape recorder with 13 FM channels. This

  3. Secondary ageing in an Al-Cu-Mg alloy with high Cu/Mg ratio

    Energy Technology Data Exchange (ETDEWEB)

    Dupasquier, A.; Folegati, P. [Politecnico di Milano (Italy). Ist. di Fisica della Materia; Ferragut, R. [Politecnico di Milano (Italy). Ist. di Fisica della Materia; IFIMAT, Univ. Nacional del Centro de la Provincia de Buenos Aires and CICPBA, Tandil (Argentina); Massazza, M.; Riontino, G. [Ist. Nazionale di Fisica della Materia, Dipt. di Chimica I.F.M., Univ. di Torino (Italy); Somoza, A. [IFIMAT, Univ. Nacional del Centro de la Provincia de Buenos Aires and CICPBA, Tandil (Argentina)

    2002-07-01

    The mechanisms governing secondary ageing (structural transformations occurring at low temperature after a heat treatment at higher temperature) were investigated by combined measurements of positron lifetimes, Vickers microhardness measurements and differential scanning calorimetry (DSC) on a laboratory alloy (Al-4.5 wt.% Cu-0.56 wt.% Mg). The results show that hardening occurs at a much slower rate than in case of primary ageing at RT. The positron lifetime data suggest that the hardening rate is controlled by slow release of vacancies from Cu-rich clusters formed during the initial high temperature treatment. The hardening stage is concomitant with an increase of the positron lifetime, and has probably the same origin, which is the formation of solute clusters containing vacancies and Mg as essential components. The formation at low temperature of new structures is also demonstrated by DSC. (orig.)

  4. High-energy {gamma}-irradiation effect on physical ageing in Ge-Se glasses

    Energy Technology Data Exchange (ETDEWEB)

    Golovchak, R. [Lviv Scientific Research Institute of Materials of SRC ' Carat' , 202 Stryjska Str., Lviv, UA-79031 (Ukraine); Kozdras, A. [Department of Physics of Opole University of Technology, 75 Ozimska Str., Opole, PL-45370 (Poland); Department of Economy of Academy of Management and Administration in Opole, 18 Niedzialkowski Str., Opole, PL-45085 (Poland); Kozyukhin, S. [Institute of General and Inorganic Chemistry of RAS, Leninsky Pr. 31, Moscow 199991 (Russian Federation); Shpotyuk, O. [Lviv Scientific Research Institute of Materials of SRC ' Carat' , 202 Stryjska Str., Lviv, UA-79031 (Ukraine); Institute of Physics of Jan Dlugosz University, 13/15 al. Armii Krajowej, Czestochowa, PL-42201 (Poland)], E-mail: shpotyuk@novas.lviv.ua

    2009-09-01

    Effect of Co{sup 60} {gamma}-irradiation on physical ageing in binary Ge{sub x}Se{sub 100-x} glasses (5 {<=} x {<=} 27) is studied using conventional differential scanning calorimetry method. It is shown, that high-energy irradiation leads to additional increase in the glass transition temperature and endothermic peak area near the glass transition region over the one induced by isochronal storage of these glasses at normal conditions. This {gamma}-induced physical ageing is shown to be well-pronounced in Se-rich glasses (x < 20), while only negligible changes are recorded for glasses of 20 {<=} x {<=} 27 compositions. The effect under consideration is supposed to be associated with {gamma}-activated structural relaxation of the glass network towards thermodynamic equilibrium of supercooled liquid.

  5. Social conflicts and historical totality in high middle ages (5th-10th century

    Directory of Open Access Journals (Sweden)

    Mário Jorge Bastos da Motta

    2015-01-01

    Full Text Available The study of the great transitions enjoys, in these days, a considerable degree of low status in the field of History. Maybe it's not hard to see the reasons of such absurd contradiction - at least if we consider that the essence of the subject in question lies in the study of the changes and transformations! Postmodernism, denial of the knowability or even the existence of the real, micro-history, fascination for the immobility, the continuities and the resistance to change, a more or less dense ‘description’, prevalent, are hegemonic tendencies in the historiographical field that help us to understand the feeling, almost widespread nowadays, that the attempted framing of the transition processes is an extemporaneous task, a surpassed demand! I propose, in this paper, in the context of Iberian's High Middle Ages, the analysis of the transition from Antiquity to the Middle Ages in its fundamental structuring elements.

  6. Early Age-Related Functional Connectivity Decline in High-Order Cognitive Networks

    Science.gov (United States)

    Siman-Tov, Tali; Bosak, Noam; Sprecher, Elliot; Paz, Rotem; Eran, Ayelet; Aharon-Peretz, Judith; Kahn, Itamar

    2017-01-01

    As the world ages, it becomes urgent to unravel the mechanisms underlying brain aging and find ways of intervening with them. While for decades cognitive aging has been related to localized brain changes, growing attention is now being paid to alterations in distributed brain networks. Functional connectivity magnetic resonance imaging (fcMRI) has become a particularly useful tool to explore large-scale brain networks; yet, the temporal course of connectivity lifetime changes has not been established. Here, an extensive cross-sectional sample (21–85 years old, N = 887) from a public fcMRI database was used to characterize adult lifespan connectivity dynamics within and between seven brain networks: the default mode, salience, dorsal attention, fronto-parietal control, auditory, visual and motor networks. The entire cohort was divided into young (21–40 years, mean ± SD: 25.5 ± 4.8, n = 543); middle-aged (41–60 years, 50.6 ± 5.4, n = 238); and old (61 years and above, 69.0 ± 6.3, n = 106) subgroups. Correlation matrices as well as a mixed model analysis of covariance indicated that within high-order cognitive networks a considerable connectivity decline is already evident by middle adulthood. In contrast, a motor network shows increased connectivity in middle adulthood and a subsequent decline. Additionally, alterations in inter-network interactions are noticeable primarily in the transition between young and middle adulthood. These results provide evidence that aging-related neural changes start early in adult life. PMID:28119599

  7. Does cyclic stress and accelerated ageing influence the wear behavior of highly crosslinked polyethylene?

    Science.gov (United States)

    Affatato, Saverio; De Mattia, Jonathan Salvatore; Bracco, Pierangiola; Pavoni, Eleonora; Taddei, Paola

    2016-06-01

    First-generation (irradiated and remelted or annealed) and second-generation (irradiated and vitamin E blended or doped) highly crosslinked polyethylenes were introduced in the last decade to solve the problems of wear and osteolysis. In this study, the influence of the Vitamin-E addition on crosslinked polyethylene (XLPE_VE) was evaluated by comparing the in vitro wear behavior of crosslinked polyethylene (XLPE) versus Vitamin-E blended polyethylene XLPE and conventional ultra-high molecular weight polyethylene (STD_PE) acetabular cups, after accelerated ageing according to ASTM F2003-02 (70.0±0.1°C, pure oxygen at 5bar for 14 days). The test was performed using a hip joint simulator run for two millions cycles, under bovine calf serum as lubricant. Mass loss was found to decrease along the series XLPE_VE>STD_PE>XLPE, although no statistically significant differences were found between the mass losses of the three sets of cups. Micro-Raman spectroscopy was used to investigate at a molecular level the morphology changes induced by wear. The spectroscopic analyses showed that the accelerated ageing determined different wear mechanisms and molecular rearrangements during testing with regards to the changes in both the chain orientation and the distribution of the all-trans sequences within the orthorhombic, amorphous and third phases. The results of the present study showed that the addition of vitamin E was not effective to improve the gravimetric wear of PE after accelerated ageing. However, from a molecular point of view, the XLPE_VE acetabular cups tested after accelerated ageing appeared definitely less damaged than the STD_PE ones and comparable to XLPE samples.

  8. High-precision 40Ar/39Ar age for the Jehol Biota

    Science.gov (United States)

    Chang, S.; Zhang, H.; Renne, P. R.; Fang, Y.

    2008-12-01

    Abundant fossils of the terrestrial Jehol Biota, including plants, insects, dinosaurs, birds, mammals and freshwater invertebrates, were discovered from the Yixian Formation and the overlying Jiufotang Formation in Inner Mongolia, Hebei Province and Liaoning Province, northeastern China. Because of the exceptional preservation of fossils, the Jehol Biota is one of the most important Mesozoic fossil outcrops and referred to as a "Mesozoic Pompeii". The Jehol Biota has provided a rare opportunity to address questions about the origin of birds, the evolution of feathers and flight, the early diversification of angiosperms and the timing of the radiation of placental mammals. The Tuchengzi Formation, which lies unconformably just below the Yixian Formation and consists mainly of variegated sandstones, is less fossiliferous than the two overlying formations. However, dinosaur tracks, silicified wood and compressed plants are found in this formation. A systematic 40Ar/39Ar dating of the Yixian and the Jiufotang formations was undertaken to provide a framework for understanding the timing and duration of the Jehol Biota and evolutionary events represented within it. Furthermore, determining the absolute age of the Tuchengzi Formation provides information to interpret abundant dinosaur tracks within and provide better age constrains for the beginning of the Jehol Biota. Here we present robust high-precision 40Ar/39Ar data for six tuff samples and two basalt samples collected from the Tuchengzi, the Yixian and the Jiufotang formations near the classic outcrops in western Liaoning, NE China. We obtain an age of 139.5 ± 1.0 Ma for the uppermost Tuchengzi Formation, an age of 129.7 ± 0.5 Ma for a basaltic lava from the bottom of the Yixian Formation and an age of 122.1 ± 0.3 Ma for a tuff from the base of the overlying Jiufotang Formation. Our data indicate that the Yixian Formation was deposited during the Early Cretaceous, the Barremian to early Aptian, within a time span

  9. April 25, 2003, FY2003 Progress Summary and FY2002 Program Plan, Statement of Work and Deliverables for Development of High Average Power Diode-Pumped Solid State Lasers,and Complementary Technologies, for Applications in Energy and Defense

    Energy Technology Data Exchange (ETDEWEB)

    Meier, W; Bibeau, C

    2005-10-25

    The High Average Power Laser Program (HAPL) is a multi-institutional, synergistic effort to develop inertial fusion energy (IFE). This program is building a physics and technology base to complement the laser-fusion science being pursued by DOE Defense programs in support of Stockpile Stewardship. The primary institutions responsible for overseeing and coordinating the research activities are the Naval Research Laboratory (NRL) and Lawrence Livermore National Laboratory (LLNL). The current LLNL proposal is a companion document to the one submitted by NRL, for which the driver development element is focused on the krypton fluoride excimer laser option. The NRL and LLNL proposals also jointly pursue complementary activities with the associated rep-rated laser technologies relating to target fabrication, target injection, final optics, fusion chamber, target physics, materials and power plant economics. This proposal requests continued funding in FY03 to support LLNL in its program to build a 1 kW, 100 J, diode-pumped, crystalline laser, as well as research into high gain fusion target design, fusion chamber issues, and survivability of the final optic element. These technologies are crucial to the feasibility of inertial fusion energy power plants and also have relevance in rep-rated stewardship experiments. The HAPL Program pursues technologies needed for laser-driven IFE. System level considerations indicate that a rep-rated laser technology will be needed, operating at 5-10 Hz. Since a total energy of {approx}2 MJ will ultimately be required to achieve suitable target gain with direct drive targets, the architecture must be scaleable. The Mercury Laser is intended to offer such an architecture. Mercury is a solid state laser that incorporates diodes, crystals and gas cooling technologies.

  10. Prime-time television exposure to high priority school-aged social-developmental issues.

    Science.gov (United States)

    Suzuki, Sherrie; Itano, Davin; Yamamoto, Loren G

    2008-03-01

    The purpose of this study is to quantify the material children and adolescents are exposed to while watching prime-time television so that school educators, health professionals, and parents can focus on issues of maximum exposure that must be addressed. Prime-time programming was recorded from 7 p.m. to 10 p.m. Hawaiian Standard Time daily for 2 weeks in July 2005. Recordings were then viewed to identify social behaviors of interest. Each hour on average, sex was referenced 1.8 times, drugs 0.6 times, tobacco 0.3 times, alcohol 2.4 times, and violence/crime 6.0 times per network. Messages advocating exercise, anti-drug advocacy, and anti-smoking advocacy were each shown 0.2 times per hour; while anti-alcohol advocacy was shown 0.1 times per hour. School educators, health professionals, and parents must recognize that prime-time television frequently exposes viewers to issues that are of critical importance to the health and social development of school-aged children and adolescents.

  11. The rate of nonallelic homologous recombination in males is highly variable, correlated between monozygotic twins and independent of age.

    Directory of Open Access Journals (Sweden)

    Jacqueline A L MacArthur

    2014-03-01

    Full Text Available Nonallelic homologous recombination (NAHR between highly similar duplicated sequences generates chromosomal deletions, duplications and inversions, which can cause diverse genetic disorders. Little is known about interindividual variation in NAHR rates and the factors that influence this. We estimated the rate of deletion at the CMT1A-REP NAHR hotspot in sperm DNA from 34 male donors, including 16 monozygotic (MZ co-twins (8 twin pairs aged 24 to 67 years old. The average NAHR rate was 3.5 × 10(-5 with a seven-fold variation across individuals. Despite good statistical power to detect even a subtle correlation, we observed no relationship between age of unrelated individuals and the rate of NAHR in their sperm, likely reflecting the meiotic-specific origin of these events. We then estimated the heritability of deletion rate by calculating the intraclass correlation (ICC within MZ co-twins, revealing a significant correlation between MZ co-twins (ICC = 0.784, p = 0.0039, with MZ co-twins being significantly more correlated than unrelated pairs. We showed that this heritability cannot be explained by variation in PRDM9, a known regulator of NAHR, or variation within the NAHR hotspot itself. We also did not detect any correlation between Body Mass Index (BMI, smoking status or alcohol intake and rate of NAHR. Our results suggest that other, as yet unidentified, genetic or environmental factors play a significant role in the regulation of NAHR and are responsible for the extensive variation in the population for the probability of fathering a child with a genomic disorder resulting from a pathogenic deletion.

  12. Dark-ages reionization and galaxy formation simulation--VII. The sizes of high-redshift galaxies

    CERN Document Server

    Liu, Chuanwu; Poole, Gregory; Angel, Paul; Duffy, Alan; Geil, Paul; Mesinger, Andrei; Wyithe, Stuart

    2016-01-01

    We investigate high-redshift galaxy sizes using a semi-analytic model constructed for the Dark-ages Reionization And Galaxy-formation Observables from Numerical Simulation project. Our fiducial model, including strong feedback from supernovae and photoionization background, accurately reproduces the evolution of the stellar mass function and luminosity function. Using this model, we study the size--luminosity relation of galaxies and find that the effective radius scales with UV luminosity as $R_\\mathrm{e}\\propto L^{0.25}$ at $z{\\sim}5$--$9$. We show that recently discovered very luminous galaxies at $z{\\sim}7$ (Bowler et al. 2016) and $z{\\sim}11$ (Oesch et al. 2016) lie on our predicted size--luminosity relations. We find that a significant fraction of galaxies at $z>6$ will not be resolved by JWST, but GMT will have the ability to resolve all galaxies in haloes above the atomic cooling limit. We show that our fiducial model successfully reproduces the redshift evolution of average galaxy sizes at $z>5$. We ...

  13. Dark-ages reionization and galaxy-formation simulation - VII. The sizes of high-redshift galaxies

    Science.gov (United States)

    Liu, Chuanwu; Mutch, Simon J.; Poole, Gregory B.; Angel, P. W.; Duffy, Alan R.; Geil, Paul M.; Mesinger, Andrei; Wyithe, J. Stuart B.

    2017-03-01

    We investigate high-redshift galaxy sizes using a semi-analytic model constructed for the Dark-ages Reionization And Galaxy-formation Observables from Numerical Simulation project. Our fiducial model, including strong feedback from supernovae and photoionization background, accurately reproduces the evolution of the stellar mass function and ultraviolet (UV) luminosity function. Using this model, we study the size-luminosity relation of galaxies and find that the effective radius scales with UV luminosity as Re ∝ L0.25 at z ∼ 5-9. We show that recently discovered very luminous galaxies at z ∼ 7 and 11 lie on our predicted size-luminosity relations. We find that a significant fraction of galaxies at z > 8 will not be resolved by James Webb Space Telescope, but Giant Magellan Telescope will have the ability to resolve all galaxies in haloes above the atomic cooling limit. We show that our fiducial model successfully reproduces the redshift evolution of average galaxy sizes at z > 5. We also explore galaxy sizes in models without supernova feedback. The no-supernova feedback models produce galaxy sizes that are smaller than observations. We therefore confirm that supernova feedback plays an important role in determining the size-luminosity relation of galaxies and its redshift evolution during reionization.

  14. VARIATION OF SUBSTRUCTURES OF PEARLITIC HEAT RESISTANT STEEL AFTER HIGH TEMPERATURE AGING

    Institute of Scientific and Technical Information of China (English)

    R.C.Yang; K.Chen; H.X.Feng; H.Wang

    2004-01-01

    The observations of dislocations, substructures and other microstructural details were conducted mainly by means of transmission electron microscope (TEM) and scanning electron microscope (SEM) for 12Cr1Mo V pearlitic heat-resistant steel. It is shown that during the high temperature long-term aging, the disordered and jumbled phasetransformed dislocations caused by normalized cooling are recovered and rearranged into cell substructures, and then the dislocation density is reduced gradually. Finally a low density linear dislocation configuration and a stabler dislocation network are formed and ferritic grains grow considerably.

  15. [Attenuated Total Reflection Infrared Spectroscopy for Degradation Profile of High Density Polyethylene after Weathering Aging].

    Science.gov (United States)

    Guo, Jun-jun; Yan, Hua; Bao, He-bin; Wang, Xue-mei; Hu, Zhi-de; Yang, Jian-jian

    2015-06-01

    High density polyethylene (HDPE) was widely used as rotational packaging case in the material reserve field. The chemical changes of HDPE, exposed to particular climatic conditions of tropic marine atmosphere for one year-long in Wanning Hainan, were elucidated by the attenuated total reflection infrared spectroscopy (ATR-FTIR). The structural changes were studied qualitatively, mainly from the polymeric chain breaking, branching and oxidation to distinguish the degradation profile. The variations of crystallinity & carbonyl index were also studied quantitatively according to the characteristic peaks intensity & area ratio. Finally, the relationships between structural changes and mechanical properties were investigated. The results showed that the polymeric chain breaking & branching play a leading role before 3 months in the aging progress. Then oxidation phenomena gradually takes place during 3-6 months. The chain branching & oxidation were predominant factors after 6 months. Nine months later, the oxidation was saturated gradually. Furthermore, the aging process is positively correlated to the temperature and irradiation. After 12 months aging, the carbonyl index increased by 112 times and crystallinity was 10% higher than before. The tensile/bending modulus deceased faster than tensile/bending strength of HDPE. The linear degree of tensile modulus and carbonyl index was 0.97. The degree of linearity of tensile strength and crystallinity calculated by feature bands (720-730 cm(-1)) was 0.96. It showed that the mechanical properties of HDPE can be speculated from the structural changes by ATR-FTIR.

  16. Alzheimer's disease and non-demented high pathology control nonagenarians: comparing and contrasting the biochemistry of cognitively successful aging.

    Directory of Open Access Journals (Sweden)

    Chera L Maarouf

    Full Text Available The amyloid cascade hypothesis provides an economical mechanistic explanation for Alzheimer's disease (AD dementia and correlated neuropathology. However, some nonagenarian individuals (high pathology controls, HPC remain cognitively intact while enduring high amyloid plaque loads for decades. If amyloid accumulation is the prime instigator of neurotoxicity and dementia, specific protective mechanisms must enable these HPC to evade cognitive decline. We evaluated the neuropathological and biochemical differences existing between non-demented (ND-HPC and an age-matched cohort with AD dementia. The ND-HPC selected for our study were clinically assessed as ND and possessed high amyloid plaque burdens. ELISA and Western blot analyses were used to quantify a group of proteins related to APP/Aβ/tau metabolism and other neurotrophic and inflammation-related molecules that have been found to be altered in neurodegenerative disorders and are pivotal to brain homeostasis and mental health. The molecules assumed to be critical in AD dementia, such as soluble or insoluble Aβ40, Aβ42 and tau were quantified by ELISA. Interestingly, only Aβ42 demonstrated a significant increase in ND-HPC when compared to the AD group. The vascular amyloid load which was not used in the selection of cases, was on the average almost 2-fold greater in AD than the ND-HPC, suggesting that a higher degree of microvascular dysfunction and perfusion compromise was present in the demented cohort. Neurofibrillary tangles were less frequent in the frontal cortices of ND-HPC. Biochemical findings included elevated vascular endothelial growth factor, apolipoprotein E and the neuroprotective factor S100B in ND-HPC, while anti-angiogenic pigment epithelium derived factor levels were lower. The lack of clear Aβ-related pathological/biochemical demarcation between AD and ND-HPC suggests that in addition to amyloid plaques other factors, such as neurofibrillary tangle density and vascular

  17. Enhancement of Skeletal Muscle in Aged Rats Following High-Intensity Stretch-Shortening Contraction Training.

    Science.gov (United States)

    Rader, Erik P; Naimo, Marshall A; Layner, Kayla N; Triscuit, Alyssa M; Chetlin, Robert D; Ensey, James; Baker, Brent A

    2016-08-03

    Exercise is the most accessible, efficacious, and multifactorial intervention to improve health and treat chronic disease. High-intensity resistance exercise, in particular, also maximizes skeletal muscle size and strength-outcomes crucial at advanced age. However, such training is capable of inducing muscle maladaptation when misapplied at old age. Therefore, characterization of parameters (e.g., mode and frequency) that foster adaptation is an active research area. To address this issue, we utilized a rodent model that allowed training at maximal intensity in terms of muscle activation and tested the hypothesis that muscles of old rats adapt to stretch-shortening contraction (SSC) training, provided the training frequency is sufficiently low. At termination of training, normalized muscle mass (i.e., muscle mass divided by tibia length) and muscle quality (isometric force divided by normalized muscle mass) were determined. For young rats, normalized muscle mass increased by ∼20% regardless of training frequency. No difference was observed for muscle quality values after 2 days versus 3 days per week training (0.65 ± 0.09 N/mg/mm vs. 0.59 ± 0.05 N/mg/mm, respectively). For old rats following 3 days per week training, normalized muscle mass was unaltered and muscle quality was 30% lower than young levels. Following 2 days per week training at old age, normalized muscle mass increased by 17% and muscle quality was restored to young levels. To investigate this enhanced response, oxidative stress was assessed by lipid peroxidation quantification. For young rats, lipid peroxidation levels were unaltered by training. With aging, baseline levels of lipid peroxidation increased by 1.5-fold. For old rats, only 2 days per week training decreased lipid peroxidation to levels indistinguishable from young values. These results imply that, appropriately scheduled high-intensity SSC training at old age is capable of restoring muscle to a younger phenotype in terms

  18. Time-average dynamic speckle interferometry

    Science.gov (United States)

    Vladimirov, A. P.

    2014-05-01

    For the study of microscopic processes occurring at structural level in solids and thin biological objects, a method of dynamic speckle interferometry successfully applied. However, the method has disadvantages. The purpose of the report is to acquaint colleagues with the method of averaging in time in dynamic speckle - interferometry of microscopic processes, allowing eliminating shortcomings. The main idea of the method is the choice the averaging time, which exceeds the characteristic time correlation (relaxation) the most rapid process. The method theory for a thin phase and the reflecting object is given. The results of the experiment on the high-cycle fatigue of steel and experiment to estimate the biological activity of a monolayer of cells, cultivated on a transparent substrate is given. It is shown that the method allows real-time visualize the accumulation of fatigue damages and reliably estimate the activity of cells with viruses and without viruses.

  19. Raman spectroscopy for highly accurate estimation of the age of refrigerated porcine muscle

    Science.gov (United States)

    Timinis, Constantinos; Pitris, Costas

    2016-03-01

    The high water content of meat, combined with all the nutrients it contains, make it vulnerable to spoilage at all stages of production and storage even when refrigerated at 5 °C. A non-destructive and in situ tool for meat sample testing, which could provide an accurate indication of the storage time of meat, would be very useful for the control of meat quality as well as for consumer safety. The proposed solution is based on Raman spectroscopy which is non-invasive and can be applied in situ. For the purposes of this project, 42 meat samples from 14 animals were obtained and three Raman spectra per sample were collected every two days for two weeks. The spectra were subsequently processed and the sample age was calculated using a set of linear differential equations. In addition, the samples were classified in categories corresponding to the age in 2-day steps (i.e., 0, 2, 4, 6, 8, 10, 12 or 14 days old), using linear discriminant analysis and cross-validation. Contrary to other studies, where the samples were simply grouped into two categories (higher or lower quality, suitable or unsuitable for human consumption, etc.), in this study, the age was predicted with a mean error of ~ 1 day (20%) or classified, in 2-day steps, with 100% accuracy. Although Raman spectroscopy has been used in the past for the analysis of meat samples, the proposed methodology has resulted in a prediction of the sample age far more accurately than any report in the literature.

  20. Comprehensive Evaluation of Fast-Response, Reynolds-Averaged Navier-Stokes, and Large-Eddy Simulation Methods Against High-Spatial-Resolution Wind-Tunnel Data in Step-Down Street Canyons

    Science.gov (United States)

    Hayati, Arash Nemati; Stoll, Rob; Kim, J. J.; Harman, Todd; Nelson, Matthew A.; Brown, Michael J.; Pardyjak, Eric R.

    2017-08-01

    Three computational fluid dynamics (CFD) methods with different levels of flow-physics modelling are comprehensively evaluated against high-spatial-resolution wind-tunnel velocity data from step-down street canyons (i.e., a short building downwind of a tall building). The first method is a semi-empirical fast-response approach using the Quick Urban Industrial Complex (QUIC-URB) model. The second method solves the Reynolds-averaged Navier-Stokes (RANS) equations, and the third one utilizes a fully-coupled fluid-structure interaction large-eddy simulation (LES) model with a grid-turbulence inflow generator. Unlike typical point-by-point evaluation comparisons, here the entire two-dimensional wind-tunnel dataset is used to evaluate the dynamics of dominant flow topological features in the street canyon. Each CFD method is scrutinized for several geometric configurations by varying the downwind-to-upwind building-height ratio (H_d/H_u) and street canyon-width to building-width aspect ratio ( S / W) for inflow winds perpendicular to the upwind building front face. Disparities between the numerical results and experimental data are quantified in terms of their ability to capture flow topological features for different geometric configurations. Overall, all three methods qualitatively predict the primary flow topological features, including a saddle point and a primary vortex. However, the secondary flow topological features, namely an in-canyon separation point and secondary vortices, are only well represented by the LES method despite its failure for taller downwind building cases. Misrepresentation of flow-regime transitions, exaggeration of the coherence of recirculation zones and wake fields, and overestimation of downwards vertical velocity into the canyon are the main defects in QUIC-URB, RANS and LES results, respectively. All three methods underestimate the updrafts and, surprisingly, QUIC-URB outperforms RANS for the streamwise velocity component, while RANS is

  1. Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; DePiero, A H; Garza, R G; Tarver, C M

    1999-06-01

    Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges.

  2. Mix design of concrete with high content of mineral additions: Optimisation to improve early age strength

    Energy Technology Data Exchange (ETDEWEB)

    M.I.A. Khokhar; E. Roziere; P. Turcry; F. Grondin; A. Loukili [Institut de Recherche en Genie Civil et Mecanique (GeM), Nantes (France)

    2010-05-15

    The concrete industry is an important source of CO{sub 2} gas emissions. The cement used in the design of concrete is the result of a chemical process linked to the decarbonation of limestone conducted at high temperature and results in a significant release of carbon dioxide. Under the project EcoBeton (Green concrete) funded by the French National Research Agency (ANR), concrete mixtures have been designed with a low cement quantity, by replacing cement by mineral additions i.e., blast-furnace slag, fly ash or limestone fillers. Replacement of cement by other materials at high percentages generally lowers the early age strength of the resulting concrete. To cope with this problem, an optimisation method for mix design of concrete using Bolomey's law has been used. Following the encouraging results obtained from mortar, a series of tests on concretes with various substitution percentages were carried out to validate the optimisation method.

  3. High folic acid intake reduces natural killer cell cytotoxicity in aged mice.

    Science.gov (United States)

    Sawaengsri, Hathairat; Wang, Junpeng; Reginaldo, Christina; Steluti, Josiane; Wu, Dayong; Meydani, Simin Nikbin; Selhub, Jacob; Paul, Ligi

    2016-04-01

    Presence of unmetabolized folic acid in plasma, which is indicative of folic acid intake beyond the metabolic capacity of the body, is associated with reduced natural killer (NK) cell cytotoxicity in postmenopausal women ≥50years. NK cells are cytotoxic lymphocytes that are part of the innate immune system critical for surveillance and defense against virus-infected and cancer cells. We determined if a high folic acid diet can result in reduced NK cell cytotoxicity in an aged mouse model. Female C57BL/6 mice (16-month-old) were fed an AIN-93M diet with the recommended daily allowance (1× RDA, control) or 20× RDA (high) folic acid for 3months. NK cytotoxicity was lower in splenocytes from mice fed a high folic acid diet when compared to mice on control diet (Pfolic acid fed mice could be due to their lower mature cytotoxic/naïve NK cell ratio (P=.03) when compared to the control mice. Splenocytes from mice on high folic acid diet produced less interleukin (IL)-10 when stimulated with lipopolysaccharide (Pfolic acid group was at least partially due to reduced IL-10 production. This study demonstrates a causal relationship between high folic acid intake and reduced NK cell cytotoxicity and provides some insights into the potential mechanisms behind this relationship.

  4. Cerebrolysin Accelerates Metamorphosis and Attenuates Aging-Accelerating Effect of High Temperature in Drosophila Melanogaster.

    Science.gov (United States)

    Navrotskaya, V; Oxenkrug, G; Vorobyova, L; Sharma, H; Muresanu, D; Summergrad, P

    2014-10-01

    Cerebrolysin® (CBL) is a neuroprotective drug used for the treatment of neurodegenerative diseases. CBL's mechanisms of action remain unclear. Involvement of tryptophan (TRP)-kynurenine (KYN) pathway in neuroprotective effect of CBL might be suggested considering that modulation of KYN pathway of TRP metabolism by CBL, and protection against eclosion defect and prolongation of life span of Drosophila melanogaster with pharmacologically or genetically-induced down-regulation of TRP conversion into KYN. To investigate possible involvement of TRP-KYN pathway in mechanisms of neuroprotective effect of CBL, we evaluated CBL effects on metamorphosis and life span of Drosophila melanogaster maintained at 23 °C and 28 °C ambient temperature. CBL accelerated metamorphosis, exerted strong tendency (p = 0.04) to prolong life span in female but not in male flies, and attenuated aging-accelerating effect of high (28 °C) ambient temperature in both female and male flies. Further research of CBL effects on metamorphosis and resistance to aging-accelerating effect of high temperature might offer new insights in mechanisms of its neuroprotective action and expand its clinical applications.

  5. High Intensity Interval Training (HIIT) improves physical performance and frailty in aged mice.

    Science.gov (United States)

    Seldeen, Kenneth Ladd; Lasky, Ginger; Leiker, Merced Maria; Pang, Manhui; Personius, Kirkwood Ely; Troen, Bruce Robert

    2017-06-17

    Sarcopenia and frailty are highly prevalent in older individuals, increasing the risk of disability and loss of independence. High intensity interval training (HIIT) may provide a robust intervention for both sarcopenia and frailty by achieving both strength and endurance benefits with lower time commitments than other exercise regimens. To better understand the impacts of HIIT during aging, we compared 24-month-old C57BL/6J sedentary mice with those that were administered 10-minute uphill treadmill HIIT sessions three times per week over 16 weeks. Baseline and endpoint assessments included body composition, physical performance, and frailty based upon criteria from the Fried physical frailty scale. HIIT trained mice demonstrated dramatic improvement in grip strength (HIIT 10.9% versus -3.9% in sedentary mice), treadmill endurance (32.6% versus -2.0%), and gait speed (107.0% versus 39.0%). Muscles from HIIT mice also exhibited greater mass, larger fiber size, and an increase in mitochondrial biomass. Furthermore, HIIT exercise showed dramatic reduction in frailty scores in 5 of 6 mice that were frail or pre-frail at baseline, with 4 ultimately becoming non-frail. The uphill treadmill HIIT exercise sessions were well tolerated by aged mice and led to dramatic performance gains, improvement in underlying muscle physiology, and reduction in frailty. Published by Oxford University Press on behalf of The Gerontological Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  6. High Rate and Ageing Studies for the Drift Tubes of the ATLAS Muon Spectrometer

    CERN Document Server

    Zimmermann, S

    2004-01-01

    The muon spectrometer of Atlas, one of the 4 experiments currently under construction at the Large Hadron Collider LHC, relies on Monitored Drift Tubes (MDTs) for track reconstruction in most of its regions. The MDTs will have to sustain count rates up to 1500 Hz/cm and must be able to survive an accumulated charge of up to 0.6 C/cm during 10 years of operation. This thesis presents results of high rate and ageing studies conducted at the CERN Gamma Irradiation Facility GIF; a series production Atlas muon chamber and a prototype of the gas recirculation system planned at LHC were used for the first time. Test beam muons were utilized to evaluate the MDT high rate behaviour; questions of resolution, efficiency and changes in the drift properties of the operating gas were addressed. The measurements were complemented by simulations with the program GARFIELD. For the ageing study the MDTs were irradiated over a period of several months, in which their performance was monitored weekly with cosmic muons. A loss in...

  7. Ensemble average theory of gravity

    Science.gov (United States)

    Khosravi, Nima

    2016-12-01

    We put forward the idea that all the theoretically consistent models of gravity have contributions to the observed gravity interaction. In this formulation, each model comes with its own Euclidean path-integral weight where general relativity (GR) has automatically the maximum weight in high-curvature regions. We employ this idea in the framework of Lovelock models and show that in four dimensions the result is a specific form of the f (R ,G ) model. This specific f (R ,G ) satisfies the stability conditions and possesses self-accelerating solutions. Our model is consistent with the local tests of gravity since its behavior is the same as in GR for the high-curvature regime. In the low-curvature regime the gravitational force is weaker than in GR, which can be interpreted as the existence of a repulsive fifth force for very large scales. Interestingly, there is an intermediate-curvature regime where the gravitational force is stronger in our model compared to GR. The different behavior of our model in comparison with GR in both low- and intermediate-curvature regimes makes it observationally distinguishable from Λ CDM .

  8. The influence of age and high-frequency hearing loss on sensitivity to temporal fine structure at low frequencies (L).

    Science.gov (United States)

    Moore, Brian C J; Glasberg, Brian R; Stoev, Martin; Füllgrabe, Christian; Hopkins, Kathryn

    2012-02-01

    Sensitivity to temporal fine structure (TFS) at low frequencies may be adversely affected by hearing loss at high frequencies even when absolute thresholds at low frequencies are within the normal range. However, in several studies suggesting this, the effects of hearing loss and age were confounded. Here, interaural phase discrimination (IPD) thresholds for pure tones at 500 and 750 Hz were measured for 39 subjects with ages from 61 to 83 yr. All subjects had near-normal audiometric thresholds at low frequencies, but thresholds varied across subjects at high frequencies. IPD thresholds were correlated with age. IPD thresholds for the test frequency of 750 Hz were weakly correlated with absolute thresholds at high frequencies, but these correlations became non-significant when the effect of age was partialed out. The results do not confirm that sensitivity to TFS at low frequencies is influenced by hearing loss at high frequencies, independently of age.

  9. Characterization of Stoichiometric and Aging Effects on NiTiHf High Temperature Shape Memory Alloys

    Science.gov (United States)

    Coughlin, Daniel Robert

    NiTiHf ternary alloys exhibit attractive high temperature shape memory alloy (HTSMA) properties. Material properties include moderate transformation strain, relatively high transformation temperature, stable pseudoelastic (PE) behavior, and very small irrecoverable strain during load biased tests. The addition of Hf is more attractive than Pt and Pd due to the fact that Hf has a lower cost. Four NiTiHf alloys with different chemical compositions spanning stoichiometry were used to analyze microstructure and mechanical behavior. Research will mainly be focused on the Ni-rich alloys based on that the Ni-lean alloys do not exhibit the previously mentioned HTSMA material properties. The alloys analyzed all had 20(at.)% Hf with varying Ti concentrations (29(at.)%, 29.7(at.)%, 30(at.)%, and 30.5(at.)%). All of the alloys were formed by induction melting, homogenized at 1050C for 72hrs, and then hot extruded with a diameter reduction of 7:1 at a temperature of 900C. In addition to the homogenized and extruded condition, several short-term aging cycles above 400C were completed on each of the alloys. Certain microstructure and mechanical properties are obtained when Hf is added to NiTi and a proper aging cycle is used. Results from isothermal compression tests that were executed above the austenite finish temperature determined that the Ni-rich NiTiHf alloys exhibited all the necessary properties to be considered for HTSMA applications. The test temperature range of the isothermal compression tests were chosen to characterize the transition from PE behavior to austenite plasticity and to examine the deformation behavior of the B2 phase at high temperatures. Results from compression tests showed a strengthening effect when the test temperature was increased through the PE test region. The strengthening effect is due to the yield stress and plasticity being related to the stress induced martensite that is created during the compression test executed above the austenite

  10. Body mass index and age at menarche in Peruvian children living at high altitude and at sea level.

    Science.gov (United States)

    Gonzales, G F; Villena, A

    1996-04-01

    The present study was designed to determine the relationship between body mass index (BMI) and age at menarche in girls (aged 10-19 years) living in Lima (150 m) and in Cerro de Pasco (4340 m above sea level). The purpose of the study was to determine whether the relationships between BMI and both age at menarche and chronological age differ between girls living at low and at high altitude. The ratio weight/height (the Benn index) was used in the present study as a variant of BMI because the exponent minimizes the relationship with height and maximizes the relationship with weight. From 10 to 16 years of age the Benn index of highlander girls was lower than that for girls at sea level, but at 17-19 years the differences disappeared. A later age at menarche was observed at high altitude than at sea level after controlling for socioeconomic status and for the Benn index. The value of the Benn index at the time of menarche, after controlling for chronological age in the analysis, was significantly higher at high altitude than at sea level. It was also observed that the higher the chronological age, the lower the value of the Benn index at the time of menarche. Using the median ages at menarche in Lima and in Cerro de Pasco, we found that a higher Benn index at the time of menarche is still observed at high altitude compared with girls from sea level. In Lima body weight and height were directly related to age at menarche (p Cerro de Pasco only weight was related to age at menarche (p Cerro de Pasco is an independent effect of altitude. Because the Benn index for menarche was different at sea level and at high altitude, we conclude that regression equations to predict age at menarche must include altitude as an independent variable.

  11. A sixth order averaged vector field method

    OpenAIRE

    Li, Haochen; Wang, Yushun; Qin, Mengzhao

    2014-01-01

    In this paper, based on the theory of rooted trees and B-series, we propose the concrete formulas of the substitution law for the trees of order =5. With the help of the new substitution law, we derive a B-series integrator extending the averaged vector field (AVF) method to high order. The new integrator turns out to be of order six and exactly preserves energy for Hamiltonian systems. Numerical experiments are presented to demonstrate the accuracy and the energy-preserving property of the s...

  12. High-protein-low-carbohydrate diet: deleterious metabolic and cardiovascular effects depend on age.

    Science.gov (United States)

    Bedarida, Tatiana; Baron, Stephanie; Vessieres, Emilie; Vibert, Francoise; Ayer, Audrey; Marchiol-Fournigault, Carmen; Henrion, Daniel; Paul, Jean-Louis; Noble, Florence; Golmard, Jean-Louis; Beaudeux, Jean-Louis; Cottart, Charles-Henry; Nivet-Antoine, Valerie

    2014-09-01

    High-protein-low-carbohydrate (HP-LC) diets have become widespread. Yet their deleterious consequences, especially on glucose metabolism and arteries, have already been underlined. Our previous study (2) has already shown glucose intolerance with major arterial dysfunction in very old mice subjected to an HP-LC diet. The hypothesis of this work was that this diet had an age-dependent deleterious metabolic and cardiovascular outcome. Two groups of mice, young and adult (3 and 6 mo old), were subjected for 12 wk to a standard or to an HP-LC diet. Glucose and lipid metabolism was studied. The cardiovascular system was explored from the functional stage with Doppler-echography to the molecular stage (arterial reactivity, mRNA, immunohistochemistry). Young mice did not exhibit any significant metabolic modification, whereas adult mice presented marked glucose intolerance associated with an increase in resistin and triglyceride levels. These metabolic disturbances were responsible for cardiovascular damages only in adult mice, with decreased aortic distensibility and left ventricle dysfunction. These seemed to be the consequence of arterial dysfunctions. Mesenteric arteries were the worst affected with a major oxidative stress, whereas aorta function seemed to be maintained with an appreciable role of cyclooxygenase-2 to preserve endothelial function. This study highlights for the first time the age-dependent deleterious effects of an HP-LC diet on metabolism, with glucose intolerance and lipid disorders and vascular (especially microvessels) and cardiac functions. This work shows that HP-LC lead to equivalent cardiovascular alterations, as observed in very old age, and underlines the danger of such diet.

  13. Age-related changes in dating aggression in Spanish high school students.

    Science.gov (United States)

    Fernández-González, Liria; O'Leary, K Daniel; Muñoz-Rivas, Marina Julia

    2014-04-01

    Prevention programs for dating partner aggression should be based on knowledge about when such aggression starts and how it changes. Given the very few studies regarding such trends, changes in physical, psychological, and sexual aggression against dating partners were examined in 14- to 20-year-old Spanish high school students (N = 2,016). Overall, psychological aggression increased linearly, whereas physical aggression had a negative quadratic association, peaking at 16 to 17 years for males and females. Sexual aggression was infrequent, but it spiked at age 16 for males. Although physical aggression diminished in late adolescence, injuries as a consequence of such aggression increased linearly for females, and they were also significantly higher for females (14.9%) than for males (3%) at ages 18 to 20 years. The findings support the hypothesis that dating physical aggression for males and females peaks during middle-to-late adolescence and shows a similar developmental pattern to other antisocial and criminal behaviors. Prevention of dating aggression, escalation of such aggression, and prevention of injury should consider developmental trends in dating aggression.

  14. Sleep Patterns in School-Age Children with Asperger Syndrome or High-Functioning Autism: A Follow-Up Study

    Science.gov (United States)

    Allik, Hiie; Larsson, Jan-Olov; Smedje, Hans

    2008-01-01

    The course of sleep patterns over 2-3 years was compared between 16 school-age children with Asperger syndrome (AS) or high-functioning autism (HFA) and 16 age- and gender-matched typically developing children, using 1-week actigraphy at baseline and follow-up. At baseline (mean age 11.1 years), children with AS/HFA had longer sleep latency and…

  15. Aging mechanisms for concrete components of High-Level Waste storage tanks

    Energy Technology Data Exchange (ETDEWEB)

    Kassir, M.; Bandyopadhyay, K.; Bush, S.; Mather, B.; Shewmon, P.; Streicher, M.; Thompson, B.; van Rooyen, D.; Weeks, J.

    1995-05-01

    The age-related degradation mechanisms which affect the concrete and the reinforcing steel in the high-level waste (HLW) storage tanks art evaluated with respect to their potential significance to the continued performance of the concrete, and am classified into non-significant and potentially significant. The identified potentially significant degradation mechanisms include the effects of elevated temperature, freezing and thawing, leaching of calcium hydroxide, aggressive chemical attack, and corrosion of the reinforcing steel. To the extent that available knowledge permits, these mechanisms are generically evaluated and quantified so that site-specific plans may be developed to verify whether significant degradation has occurred in the concrete, and, if so, to formulate mitigating measures to avoid further deterioration and possibly repair the degradation or pursue other management options.

  16. Gel–sol synthesis and aging effect on highly crystalline anatase nanopowder

    Indian Academy of Sciences (India)

    Sharif Shahini; Masoud Askari; S K Sadrnezhaad

    2011-10-01

    Highly crystalline TiO2 anatase nanoparticles were synthesized via gel–sol method by using titanium isopropoxide and triethanolamine. The products were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric/differential thermal analysis and nitrogen gas absorption methods. The particle size ranged from 7 to 24 nm having specific surface area of 64 to 220 m2/g. Selective Ti(OH)4 gel specifications and hydrothermal test conditions resulted in thermodynamically-stable phase-formation. Aging at 130°C for 4 h resulted in particle size of 7 nm; while at 130 and 160°C for 12 h resulted in 12 and 21 nm, respectively.

  17. Influence of age on reactivity to diverse emotional challenges in low- and high-anxiety rats.

    Science.gov (United States)

    de Oliveira, Luciana C; Gomes, Margareth Z; Brandão, Marcus L

    2011-02-01

    Studies have revealed that the extent of reactivity of high-anxiety rats to diverse challenges is different than low-anxiety rats and have provided important insights into the psychopathology of anxiety. Various factors intervene to allow defensive mechanisms to react to diverse threatening challenges, including ontogeny and the nature of the emotional challenge (e.g., conditioned vs. unconditioned). The present study investigated the extent to which a particular type of fear extrapolates to other emotional responses to diverse threatening challenges. Groups of 30- and 60-day-old rats were assigned to low freezing behavior (LFB) and high freezing behavior (HFB) groups using the contextual fear conditioning paradigm and subjected to either the fear-potentiated startle (FPS) test, novelty-induced ultrasound vocalizations (USVs) or elevated plus-maze (EPM) tests. At 30 days of age, HFB rats exhibited greater FPS than LFB rats. In contrast, prior selection of HFB and LFB did not affect the performance of 30-day-old animals in the EPM and novelty-induced USVs. Sixty-day-old animals exhibited a performance deficit in all three tests. These data suggest that the performance of young rats in animal models of anxiety parallels their selection as LFB and HFB in the contextual fear conditioning paradigm. However, the increased fear-like behavior exhibited by the 60-day-old HFB rats may elicit performance deficits in conditioned and unconditioned fear tests. These results suggest that the interaction between hyperanxiety and age may cause a performance deficit despite the animals' increased fear-like behavior when facing emotional challenges, thus resembling psychiatric patients in many respects. Copyright © 2010 ISDN. Published by Elsevier Ltd. All rights reserved.

  18. 7 CFR 1209.12 - On average.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false On average. 1209.12 Section 1209.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS....12 On average. On average means a rolling average of production or imports during the last two...

  19. Elevated high-density lipoprotein cholesterol and age-related macular degeneration: the Alienor study.

    Directory of Open Access Journals (Sweden)

    Audrey Cougnard-Grégoire

    Full Text Available BACKGROUND: Lipid metabolism and particularly high-density lipoprotein (HDL may be involved in the pathogenic mechanism of age-related macular degeneration (AMD. However, conflicting results have been reported in the associations of AMD with plasma HDL and other lipids, which may be confounded by the recently reported associations of AMD with HDL-related genes. We explored the association of AMD with plasma lipid levels and lipid-lowering medication use, taking into account most of HDL-related genes associated with AMD. METHODS: The Alienor study is a population-based study on age-related eye diseases performed in 963 elderly residents of Bordeaux (France. AMD was graded from non mydriatic color retinal photographs in three exclusive stages: no AMD (n = 430 subjects, 938 eyes; large soft distinct drusen and/or large soft indistinct drusen and/or reticular drusen and/or pigmentary abnormalities (early AMD, n = 176, 247; late AMD (n = 40, 61. Associations of AMD with plasma lipids (HDL, total cholesterol (TC, Low-density lipoprotein (LDL, and triglycerides (TG were estimated using Generalized Estimating Equation logistic regressions. Statistical analyses included 646 subjects with complete data. RESULTS: After multivariate adjustment for age, sex, educational level, smoking, BMI, lipid-lowering medication use, cardiovascular disease and diabetes, and for all relevant genetic polymorphisms (ApoE2, ApoE4, CFH Y402H, ARMS2 A69S, LIPC rs10468017, LIPC rs493258, LPL rs12678919, ABCA1 rs1883025 and CETP rs3764261, higher HDL was significantly associated with an increased risk of early (OR = 2.45, 95%CI: 1.54-3.90; P = 0.0002 and any AMD (OR = 2.29, 95%CI: 1.46-3.59; P = 0.0003. Association with late AMD was far from statistical significance (OR = 1.58, 95%CI: 0.48-5.17; p = 0.45. No associations were found for any stage of AMD with TC, LDL and TG levels, statin or fibrate drug use. CONCLUSIONS: This study suggests that elderly patients with high HDL

  20. Engineering study - alternatives for SHMS high temperature/moisture gas sample conditioners for the aging waste facility

    Energy Technology Data Exchange (ETDEWEB)

    THOMPSON, J.F.

    1999-06-02

    The Standard Hydrogen Monitoring Systems have been experiencing high temperature/moisture problems with gas samples from the Aging Waste Tanks. These moist hot gas samples have stopped the operation of the SHMS units on tanks AZ-101, AZ-102, and AY-102. This study looks at alternatives for gas sample conditioners for the Aging Waste Facility.

  1. RELAXATIONS LOSSES IN POLYETHYLENE INSULATION OF COAXIAL CABLE STRUCTURE DURING AGING IN HIGH HUMIDITY CONDITIONS

    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych

    2016-05-01

    Full Text Available Introduction. The presence of free moisture in power cables leading to the formation of tree structures - water treeing, which originate in the amorphous phase polyethylene and are a major cause of degradation of the polymer insulation. They represent the damage of the polymer size from several microns to 1 mm, developing technology for insulation defects under the combined action of the electric field and the moisture diffusing from the environment. Water treeing destroys the polymer chain, resulting in the formation of microcavities filled with moisture. The dynamics of water treeing and subtle properties largely depend on the composition, morphology of the polymer insulation, chemical nature of the defect, in which they originate. Due to the force of gravity in the water formed typical only for her region with locally ordered structure - clusters, which cause loss of relaxation. Purpose. Features presence of relaxation losses in high-frequency range in polyethylene insulation during aging in high humidity conditions of samples power and RF cables. Methodology. Samples of the power cable for the voltage of 35 kV with a cross-linked polyethylene insulation radial water-blocking protection from moisture and radio-frequency coaxial cable with thermoplastic insulation for 1440 hours in a humidity of 100%. The dielectric loss tangent measured resonance method before and after aging. Originality. Experimentally found evidence of the existence in the polymer cable insulation free water in the form of areas with locally ordered structure - clusters. It is found that the solid polyethylene insulation in the frequency dependence of dielectric loss tangent maximum relaxation shown one at 10 MHz in the initial state, and there are two additional frequency range 500 kHz - 5 MHz after moistening. For cross-linked polyethylene insulation characteristic of large width Δf of the frequency spectrum in which the observed relaxation losses. It is obvious that

  2. Highly retentive core domains in K-feldspar preserve argon ages from high temperature stages of granite exhumation

    Science.gov (United States)

    Forster, Marnie; Lister, Gordon

    2016-04-01

    Retentive core domains are characterized by diffusion parameters that imply K-feldspar should be able to retain argon even at temperatures near or above the granite solidus. In this case it should be possible to date granite emplacement using argon geochronology, and the same answer should be obtained as by using other methods. We present one case study where this is the case, from the elevated Capoas granite stock on Palawan, in the Philippines, and another where it is not, from the South Cyclades Shear Zone, on Ios, Greece. We attempt to determine the factors such as the role of fluid ingress in triggering the in situ recrystallization that can eliminate and/or modify the core domains, leading to relatively youthful ages. Thermochronology is still possible, because less retentive diffusion domains exist, but different methods need to be applied to interpret the data. The work also demonstrates that K-feldspar can be sufficiently retentive as to allow direct dating of processes that reduce the dimensions of diffusion domains, e.g., cataclased and/or recrystallized K-feldspar in fault rock and/or mylonite. These are important developments in the methodology of 40Ar/39Ar geochronology, but to further advance we need to clarify the nature of these highly retentive core domains. In particular, we need better understand how they are modified by microstructural processes during deformation and metamorphism. We need also to assess the role of any crystal structural changes during step-heating in vacuo.

  3. Aging behavior and fatigue crack propagation of high Zn-containing Al-Zn-Mg-Cu alloys with zinc variation

    National Research Council Canada - National Science Library

    Kai Wen Yunqiang Fan Guojun Wang Longbing Jin Xiwu Li Zhihui Li Yongan Zhang Baiqing Xiong

    2017-01-01

    In the present work, the influence of two-step aging treatments on hardness, electrical conductivity and mechanical properties of two high Zn-containing Al-Zn-Mg-Cu alloys with zinc content variation...

  4. The age of extremely red and massive galaxies at very high redshift

    CERN Document Server

    Castro-Rodriguez, N

    2011-01-01

    Aims. We present a determination of the intrinsic colors and ages of galaxies at very high redshift, in particular old galaxies (OGs) within extremely red objects (EROs). To date, the definition of EROs has been restricted to objects with z2.5). We therefore, refer to these objects as very high-redshift EROs (Z-EROS, herein). Methods. We analyze 63,550 galaxies selected in the XMM-LSS field. To obtain a reasonably sized sample of EROs, it is essential to consider a very wide area surveys. We identify targets within an area of 0.77 square degrees for which optical to mid-infrared data are available from SUBARU, UKIDSS, and Spitzer. We select Z-EROs based on their colors, and then perform a selection of only OGs. One of our novel innovations is to adapt the traditional method of EROs selection based on the filters I and K, to higher redshifts. Using our method, we identify 20 objects that satisfy the conditions required to be Z-EROs/OGs at redshifts 2.5~4.7. After including additional galaxies with z<2.5 ana...

  5. Increased Aβ pathology in aged Tg2576 mice born to mothers fed a high fat diet

    Science.gov (United States)

    Nizari, Shereen; Carare, Roxana O.; Hawkes, Cheryl A.

    2016-01-01

    Maternal obesity is associated with increased risk of developing diabetes, obesity and premature death in adult offspring. Mid-life diabetes, hypertension and hypercholesterolaemia are risk factors for the development of sporadic Alzheimer’s disease (AD). A key pathogenic feature of AD is the accumulation of β-amyloid (Aβ) in the brain. The purpose of this study was to investigate the effect of high fat diet feeding during early life on Aβ pathology in the Tg2576 mouse model of AD. Female mice were fed a standard (C) or high fat (HF) diet before mating and during gestation and lactation. At weaning, male offspring were fed a C diet. Significantly higher levels of guanidine-soluble Aβ and plaque loads were observed in the hippocampi of 11-month old Tg2576 mice born to mothers fed a HF diet. Changes in the extracellular matrix led to increased retention of Aβ within the parenchyma. These data support a role for maternal and gestational health on the health of the aged brain and pathologies associated with AD and may provide a novel target for both the prevention and treatment of AD. PMID:26911528

  6. Cardiac autonomic function and high-intensity interval training in middle-age men.

    Science.gov (United States)

    Kiviniemi, Antti M; Tulppo, Mikko P; Eskelinen, Joonas J; Savolainen, Anna M; Kapanen, Jukka; Heinonen, Ilkka H A; Huikuri, Heikki V; Hannukainen, Jarna C; Kalliokoski, Kari K

    2014-10-01

    The effects of short-term high-intensity interval training (HIT) on cardiac autonomic function are unclear. The present study assessed cardiac autonomic adaptations to short-term HIT in comparison with aerobic endurance training (AET). Twenty-six healthy middle-age sedentary men were randomized into HIT (n = 13, 4-6 × 30 s of all-out cycling efforts with 4-min recovery) and AET (n = 13, 40-60 min at 60% of peak workload) groups, performing six sessions within 2 wk. The participants underwent a 24-h ECG recording before and after the intervention and, additionally, recorded R-R interval data in supine position (5 min) at home every morning during the intervention. Mean HR and low-frequency (LF) and high-frequency (HF) power of R-R interval oscillation were analyzed from these recordings. Peak oxygen consumption (V˙O2peak) increased in both groups (P training, most probably by inducing larger increases in cardiac vagal activity. The acute autonomic responses to the single HIT session were not modified by short-term training.

  7. Aging of magnesium stearate under high doses gamma irradiation and oxidative conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lebeau, D.; Beuvier, L.; Cornaton, M. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Miserque, F. [CEA, DEN, DPC, SCCME, LECA, F-91191 Gif-sur-Yvette (France); Tabarant, M. [CEA, DEN, DPC, SEARS, LISL, F-91191 Gif-sur-Yvette (France); Esnouf, S. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Ferry, M., E-mail: muriel.ferry@cea.fr [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France)

    2015-05-15

    Highlights: • Magnesium stearate was radio-oxidized at very high doses using gamma-rays. • H{sub 2} emission was estimated as a function of the integrated dose. • Modifications in the organic solid were followed as a function of the integrated dose. • A non-exhaustive degradation mechanism of magnesium stearate was proposed. - Abstract: In nuclear waste packages conditioning processes, magnesium stearate is widely used because of its high lubricating properties. For safety purposes, the radiolytic degradation of these organic materials has to be better understood to be able to predict their aging in repository conditions. This study reports the radiolytic degradation of magnesium stearate, using gamma-rays at room temperature and under air. Modifications were followed using different analytical tools (XPS, ATR-FTIR, ICP-AES, ATG and mass spectrometry). It has been observed that molecules mainly formed up to 1000 kGy of gamma irradiation dose under radio-oxidation are alkanes, hydroperoxides, double bonds in the aliphatic chain, carboxylates with aliphatic chain shorter than the one of stearate and ketones. At a dose of 4000 kGy, dicarboxylic acids are observed: the formation of these molecules needs a dose of at least 1000 kGy to be created under radio-oxidation. These observations allow us to propose a non-exhaustive degradation mechanism of magnesium stearate under gamma-irradiation at room temperature and under air.

  8. Dark-ages Reionization & Galaxy Formation Simulation I: The dynamical lives of high redshift galaxies

    CERN Document Server

    Poole, Gregory B; Mutch, Simon J; Power, Chris; Duffy, Alan R; Geil, Paul M; Mesinger, Andrei; Wyithe, Stuart B

    2015-01-01

    We present the Dark-ages Reionization and Galaxy-formation Observables from Numerical Simulations (DRAGONS) program and Tiamat, the collisionless N-body simulation program upon which DRAGONS is built. The primary trait distinguishing Tiamat from other large simulation programs is its density of outputs at high redshift (100 from z=35 to z=5; roughly one every 10 Myr) enabling the construction of very accurate merger trees at an epoch when galaxy formation is rapid and mergers extremely frequent. We find that the friends-of-friends halo mass function agrees well with the prediction of Watson et al. at high masses, but deviates at low masses, perhaps due to our use of a different halo finder or perhaps indicating a break from "universal" behaviour. We then analyse the dynamical evolution of galaxies during the Epoch of Reionization finding that only a small fraction (~20%) of galactic halos are relaxed. We illustrate this using standard relaxation metrics to establish two dynamical recovery time-scales: i) halo...

  9. Teenagers' High Arrest Rates: Features of Young Age or Youth Poverty?

    Science.gov (United States)

    Males, Mike A.; Brown, Elizabeth A.

    2014-01-01

    The association of more crime with youthful age is widely accepted in social science. However, a literature search revealed no studies of the age-crime relationship that controlled for young ages' economic disadvantage. This research gap is addressed using the California Criminal Justice Statistics Center's arrest detail and Census poverty…

  10. Teenagers' High Arrest Rates: Features of Young Age or Youth Poverty?

    Science.gov (United States)

    Males, Mike A.; Brown, Elizabeth A.

    2014-01-01

    The association of more crime with youthful age is widely accepted in social science. However, a literature search revealed no studies of the age-crime relationship that controlled for young ages' economic disadvantage. This research gap is addressed using the California Criminal Justice Statistics Center's arrest detail and Census poverty…

  11. Teenagers' High Arrest Rates: Features of Young Age or Youth Poverty?

    Science.gov (United States)

    Males, Mike A.; Brown, Elizabeth A.

    2014-01-01

    The association of more crime with youthful age is widely accepted in social science. However, a literature search revealed no studies of the age-crime relationship that controlled for young ages' economic disadvantage. This research gap is addressed using the California Criminal Justice Statistics Center's arrest detail and Census…

  12. Sm-Nd age dating of high- pressure granulites and amphi- bolite from Sanggan area, North China craton

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The high pressure (HP) metamorphic age has been dated to HP rocks from the Sanggan area, North China craton. We have got garnet+whole rock isochron ages of (1 842±38) Ma for HP granulite, and (1 856 ± 26) Ma for HP amphibolite. The Sm-Nd whole rock isochron of HP granulites give out an age of (1 870±150) Ma with Nd deplet-ed mantle model age of (2 402-2 482) Ma. Considering the Nd isotope homogenization during the peak metamorphism of the HP granulite, Sm-Nd closure temperature and the retention of Nd isotopic memory in garnets partially broken down during decompression, all these isochron ages are thought to be HP metamorphic age. Furthermore, we pro-posed that the HP metamorphism took place at the end of Paleoproterozoic during the large-scale collision and assem-bly of the North China craton.

  13. Interaction of cyclic ageing at high-rate and low temperatures and safety in lithium-ion batteries

    Science.gov (United States)

    Fleischhammer, Meike; Waldmann, Thomas; Bisle, Gunther; Hogg, Björn-Ingo; Wohlfahrt-Mehrens, Margret

    2015-01-01

    The differences in the safety behaviour between un-aged and aged high-power 18650 lithium-ion cells were investigated at the cell and material level by Accelerating Rate Calorimetry (ARC) and Simultaneous Thermal Analysis (STA). Commercial cells containing a LixNi1/3Mn1/3Co1/3O2/LiyMn2O4 blend cathode, a carbon/graphite anode and a PP/PE/PP trilayer separator were aged by high-rate and low temperature cycling, leading to (i) mechanical deformation of the jelly roll and (ii) lithium plating on the anode. The results show a strong influence of the ageing history on the safety behaviour. While cycling at high current does not have a strong influence on the cell safety, lithium plating leads to a significant increase of heat formation during thermal runaway and thus to a higher hazard of safety.

  14. Level sets of multiple ergodic averages

    CERN Document Server

    Ai-Hua, Fan; Ma, Ji-Hua

    2011-01-01

    We propose to study multiple ergodic averages from multifractal analysis point of view. In some special cases in the symbolic dynamics, Hausdorff dimensions of the level sets of multiple ergodic average limit are determined by using Riesz products.

  15. Tendências genética e fenotípica para ganho de peso médio diário entre a desmama e o sobreano em uma população Angus x Nelore Genetic and phenotypic trends for average daily weight gain from weaning to 550 days of age in a Angus Nellore population

    Directory of Open Access Journals (Sweden)

    D. D'avila Balbé

    2007-02-01

    Full Text Available Foram analisados os registros de ganho médio diário entre a desmama e o sobreano (GMDDS de 33.267 animais de uma população multirracial Angus - Nelore, filhos de 525 touros, criados em 37 rebanhos, em diversas regiões do Brasil, entre os anos de 1987 e 2001. O modelo animal usado incluiu os efeitos aleatórios genético aditivo direto e materno e residual e os efeitos fixos de grupo genético do pai, da mãe e do animal e do grupo de contemporâneos pós-desmama, além da covariável idade à desmama, não ajustada. O GMDDS médio observado para a população foi 384,22g. O ano de 1999 foi o que apresentou o maior GMDDS (484,04g, e o ano de 1992, o menor (299,42g. Os coeficientes de herdabilidade estimados foram: 0,30±0,11 (direta e 0,29±0,07 (materna. O VG médio foi de -0,827g. A tendência genética estimada para essa característica foi de -0,029g/ano (PDirect and maternal heritability coefficients were estimated and genetic and phenotypic trends were predicted for average weight gain from weaning to 550 days of age (AWG from 33,267 animals of a multi-breed Angus-Nellore population, sired by 525 bulls and raised in 37 herds in several regions of Brazil, from 1987 to 2001. MTDFREML was used for estimating the (covariance components utilized to estimate the genetic direct and maternal heritability coefficients and to predict the breeding values. The animal model included as fixed the genetic group of sire, dam and animal and the pos weaning year/station/herd contemporary group and the covariate weaning age, and as ramdom, the additive genetic, maternal and residual effects. The observed AWG was 384.22g, 1999 presented the highest (484.04g and 1992 the lowest value (299.42g. The direct heritability was 0.30±0.11, the maternal h² was 0.29±0.07 and the average genetic value was -0.827g. The estimated genetic trend for AWG was -0.029g (P<0.08 and the phenotypic trend was 5.68g (P<0.05. A phenotypic progress for average weight gain from

  16. Dark-ages reionization & galaxy formation simulation IV: UV luminosity functions of high-redshift galaxies

    CERN Document Server

    Liu, Chuanwu; Angel, P W; Duffy, Alan R; Geil, Paul M; Poole, Gregory B; Mesinger, Andrei; Wyithe, J Stuart B

    2015-01-01

    In this paper we present calculations of the UV luminosity function predictions from the Dark-ages Reionization And Galaxy-formation Observables from Numerical Simulations (DRAGONS) project, which combines N-body, semi-analytic and semi-numerical modeling designed to study galaxy formation during the Epoch of Reionization. Using galaxy formation physics including supernova feedback, the model naturally reproduces the UV LFs for high-redshift star-forming galaxies from $z{\\sim}5$ through to $z{\\sim}10$. We investigate the predicted luminosity-star formation rate (SFR) relation, finding that variable SFR histories of galaxies result in a scatter around the mean relation of $0.1$-$0.3$ dex depending on UV luminosity. We find close agreement between the model and observationally derived SFR functions. We use our predicted luminosities to investigate the luminosity function below current detection limits, and the ionizing photon budget for reionization. We predict that the slope of the UV LF remains steep below cu...

  17. Accurate Switched-Voltage voltage averaging circuit

    OpenAIRE

    金光, 一幸; 松本, 寛樹

    2006-01-01

    Abstract ###This paper proposes an accurate Switched-Voltage (SV) voltage averaging circuit. It is presented ###to compensated for NMOS missmatch error at MOS differential type voltage averaging circuit. ###The proposed circuit consists of a voltage averaging and a SV sample/hold (S/H) circuit. It can ###operate using nonoverlapping three phase clocks. Performance of this circuit is verified by PSpice ###simulations.

  18. Spectral averaging techniques for Jacobi matrices

    CERN Document Server

    del Rio, Rafael; Schulz-Baldes, Hermann

    2008-01-01

    Spectral averaging techniques for one-dimensional discrete Schroedinger operators are revisited and extended. In particular, simultaneous averaging over several parameters is discussed. Special focus is put on proving lower bounds on the density of the averaged spectral measures. These Wegner type estimates are used to analyze stability properties for the spectral types of Jacobi matrices under local perturbations.

  19. Multitasking and aging: do older adults benefit from performing a highly practiced task?

    Science.gov (United States)

    Allen, Philip A; Lien, Mei-Ching; Ruthruff, Eric; Voss, Andreas

    2014-01-01

    BACKGROUND/STUDY CONTEXT: The present study examined the effect of training on age differences in performing a highly practiced task using the psychological refractory period (PRP) paradigm (Pashler, 1984, Journal of Experimental Psychology: Human Perception and Performance, 10, 358-377). Earlier training studies have concentrated on tasks that are not already overlearned. The present question of interest is whether task dual-task integration will be more efficient when single-task performance is approaching asymptotic levels. Task 1 was red/green signal discrimination (green = "go" and red = "wait"; analogous to pedestrian signals) and Task 2 was tone discrimination (white noise vs. a horn "honk"; analogous to traffic sound). The stimulus onset asynchrony (SOA) between Task 1 and Task 2 was varied (50, 150, 600, and 1000 ms). All individuals participated in eight sessions spread over 8 weeks (one session per week). Participants completed a dual-task pretest (Week 1), followed by 6 weeks of single-task testing (Weeks 2-7), followed by a dual-task posttest (Week 8). Although older adults showed larger overall dual-task costs (i.e., PRP effects), they were able to reduce the costs with practice as much as younger adults. However, even when training on Task 1 results in asymptotic performance, this still did not lead to an appreciable reduction in dual-task costs. Also, older adults, but not younger adults, responded more rapidly to green stimuli than to red stimuli in the Task 1 training latency data. The authors confirmed this green/go bias using diffusion modeling, which takes into account response time and error rates at the same time. This green/go bias is potentially dangerous at crosswalks, especially when combined with large dual-task interference, and might contribute to the high rate of crosswalk accidents in the elderly.

  20. Generalized Joint Laxity and Ligament Injuries in High School–Aged Female Volleyball Players in Japan

    Science.gov (United States)

    Sueyoshi, Ted; Emoto, Gen; Yuasa, Tomoki

    2016-01-01

    Background: Generalized joint laxity has been linked to ligamentous injuries such as anterior cruciate ligament tear and ankle sprain. Purpose/Hypothesis: The purpose of this study was to investigate generalized joint laxity and incidence of ligament injuries in high school–aged female volleyball players. It was hypothesized that volleyball players with a past history of sprains would have increased generalized joint laxity compared with those without any history and that athletes with multiple sprains would demonstrate with a higher generalized joint laxity score than those who had only 1 sprain. Study Design: Case-control study; Level of evidence, 3. Methods: Forty-seven subjects were tested for generalized joint laxity using the Beighton and Horan Joint Mobility Index (BHJMI). They were categorized into 2 groups based on the presence of past ligament injury: injury group (IG) and noninjury group (NG). The IG group was further divided into 2 groups based on whether they had a single ligamentous injury (IGS) or multiple injuries (IGM) in the past to study whether there was any difference in scores between the subgroups. The collected data were analyzed statistically with 1-way analysis of variance. Results: Subjects in the IG group scored significantly higher on the BHJMI than those in the NG group. The mean score for the IG group was 2.40 ± 1.42, as opposed to 1.24 ± 1.09 for the NG group (P = .006). Eleven subjects in the IG group had suffered multiple injuries or recurrent injuries (IGM) and scored significantly higher than the remaining 19 individuals in the IG group, who had only sustained a single injury (IGS). The mean BHJMI scores were 3.18 ± 1.47 and 1.95 ± 1.22 for IGM and IGS, respectively (P = .02). Conclusion: Female athletes with a high generalized joint laxity score may be more prone to ligament injury and potentially to recurrent ligament injuries. PMID:27761474

  1. Insomnia in school-age children with Asperger syndrome or high-functioning autism

    Directory of Open Access Journals (Sweden)

    Smedje Hans

    2006-04-01

    Full Text Available Abstract Background Asperger syndrome (AS and high-functioning autism (HFA are pervasive developmental disorders (PDD in individuals of normal intelligence. Childhood AS/HFA is considered to be often associated with disturbed sleep, in particular with difficulties initiating and/or maintaining sleep (insomnia. However, studies about the topic are still scarce. The present study investigated childhood AS/HFA regarding a wide range of parent reported sleep-wake behaviour, with a particular focus on insomnia. Methods Thirty-two 8–12 yr old children with AS/HFA were compared with 32 age and gender matched typically developing children regarding sleep and associated behavioural characteristics. Several aspects of sleep-wake behaviour including insomnia were surveyed using a structured paediatric sleep questionnaire in which parents reported their children's sleep patterns for the previous six months. Recent sleep patterns were monitored by use of a one-week sleep diary and actigraphy. Behavioural characteristics were surveyed by use of information gleaned from parent and teacher-ratings in the High-Functioning Autism Spectrum Screening Questionnaire, and in the Strengths and Difficulties Questionnaire. Results Parent-reported difficulties initiating sleep and daytime sleepiness were more common in children with AS/HFA than in controls, and 10/32 children with AS/HFA (31.2% but none of the controls fulfilled our definition of paediatric insomnia. The parent-reported insomnia corresponded to the findings obtained by actigraphy. Children with insomnia had also more parent-reported autistic and emotional symptoms, and more teacher-reported emotional and hyperactivity symptoms than those children without insomnia. Conclusion Parental reports indicate that in childhood AS/HFA insomnia is a common and distressing symptom which is frequently associated with coexistent behaviour problems. Identification and treatment of sleep problems need to be a routine

  2. ZPR-3 Assembly 11 : A cylindrical sssembly of highly enriched uranium and depleted uranium with an average {sup 235}U enrichment of 12 atom % and a depleted uranium reflector.

    Energy Technology Data Exchange (ETDEWEB)

    Lell, R. M.; McKnight, R. D.; Tsiboulia, A.; Rozhikhin, Y.; National Security; Inst. of Physics and Power Engineering

    2010-09-30

    Over a period of 30 years, more than a hundred Zero Power Reactor (ZPR) critical assemblies were constructed at Argonne National Laboratory. The ZPR facilities, ZPR-3, ZPR-6, ZPR-9 and ZPPR, were all fast critical assembly facilities. The ZPR critical assemblies were constructed to support fast reactor development, but data from some of these assemblies are also well suited for nuclear data validation and to form the basis for criticality safety benchmarks. A number of the Argonne ZPR/ZPPR critical assemblies have been evaluated as ICSBEP and IRPhEP benchmarks. Of the three classes of ZPR assemblies, engineering mockups, engineering benchmarks and physics benchmarks, the last group tends to be most useful for criticality safety. Because physics benchmarks were designed to test fast reactor physics data and methods, they were as simple as possible in geometry and composition. The principal fissile species was {sup 235}U or {sup 239}Pu. Fuel enrichments ranged from 9% to 95%. Often there were only one or two main core diluent materials, such as aluminum, graphite, iron, sodium or stainless steel. The cores were reflected (and insulated from room return effects) by one or two layers of materials such as depleted uranium, lead or stainless steel. Despite their more complex nature, a small number of assemblies from the other two classes would make useful criticality safety benchmarks because they have features related to criticality safety issues, such as reflection by soil-like material. ZPR-3 Assembly 11 (ZPR-3/11) was designed as a fast reactor physics benchmark experiment with an average core {sup 235}U enrichment of approximately 12 at.% and a depleted uranium reflector. Approximately 79.7% of the total fissions in this assembly occur above 100 keV, approximately 20.3% occur below 100 keV, and essentially none below 0.625 eV - thus the classification as a 'fast' assembly. This assembly is Fast Reactor Benchmark No. 8 in the Cross Section Evaluation

  3. Low-volume high-intensity swim training is superior to high-volume low-intensity training in relation to insulin sensitivity and glucose control in inactive middle-aged women.

    Science.gov (United States)

    Connolly, Luke J; Nordsborg, Nikolai B; Nyberg, Michael; Weihe, Pál; Krustrup, Peter; Mohr, Magni

    2016-10-01

    We tested the hypothesis that low-volume high-intensity swimming has a larger impact on insulin sensitivity and glucose control than high-volume low-intensity swimming in inactive premenopausal women with mild hypertension. Sixty-two untrained premenopausal women were randomised to an inactive control (n = 20; CON), a high-intensity low-volume (n = 21; HIT) or a low-intensity high-volume (n = 21; LIT) training group. During the 15-week intervention period, HIT performed 3 weekly 6-10 × 30-s all-out swimming intervals (average heart rate (HR) = 86 ± 3 % HRmax) interspersed by 2-min recovery periods and LIT swam continuously for 1 h at low intensity (average HR = 73 ± 3 % HRmax). Fasting blood samples were taken and an oral glucose tolerance test (OGTT) was conducted pre- and post-intervention. After HIT, resting plasma [insulin] was lowered (17 ± 34 %; P training strategy for improving insulin sensitivity, glucose control and biomarkers of vascular function in inactive, middle-aged mildly hypertensive women.

  4. Intelligence profiles of Chinese school-aged boys with high-functioning ASD and ADHD

    Directory of Open Access Journals (Sweden)

    Li G

    2017-06-01

    Full Text Available Gaizhi Li,1,* Wenqing Jiang,2,* Yasong Du,2 Kathryn Rossbach3 1Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 2Department of Child & Adolescent Psychiatry, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 3Emory Autism Center, Emory University School of Medicine, Atlanta, GA, USA *These authors contributed equally to this work Purpose: This study aimed to explore the intelligence profiles of Chinese school-aged boys with high-functioning autism spectrum disorder (HFASD and attention-deficit/hyperactivity disorder (ADHD. Additionally, differences in intelligence quotient (IQ between the HFASD group and the ADHD group were examined.Patients and methods: Thirty-two boys with HFASD, 58 boys with ADHD, and 39 typically developing (TD boys aged 6–16 years participated in this study. The ADHD group was divided into subgroups: ADHD-I (predominantly inattentive and ADHD-C (combined type. (The ADHD-H [hyperactive] group was excluded because of small sample size. The Wechsler Intelligence Scale for Children-IV Chinese version was administered to every participant, and the FSIQ (Full-Scale IQ score was used as the measure of IQ.Results: Both boys with HFASD and ADHD (ADHD-I and ADHD-C showed impairments in Processing Speed Index and FSIQ, as compared to the TD group. Lower Verbal Comprehension Index scores were found in the ASD and ADHD-I groups. Interestingly, Working Memory Index was only impaired in children with ADHD. Additionally, equivalent Perceptual Reasoning Index (PRI scores were found among the HFASD, ADHD, and TD groups.Conclusion: Results indicated that both children with ADHD and HFASD have difficulty in processing speed, which may be explained by these children having neurodevelopmental disorders. These results also indicated that working memory appears to only be impacted by having ADHD. Children

  5. High-Density Lipoprotein Function in Exudative Age-Related Macular Degeneration.

    Directory of Open Access Journals (Sweden)

    Laura Pertl

    Full Text Available High-density lipoproteins (HDL have long been implicated in the pathogenesis of age-related macular degeneration (AMD. However, conflicting results have been reported with regard to the associations of AMD with HDL-cholesterol levels. The present study is the first to assess HDL composition and metrics of HDL function in patients with exudative AMD and control patients.Blood samples were collected from 29 patients with exudative AMD and 26 age-matched control patients. Major HDL associated apolipoproteins were determined in apoB-depleted serum by immunoturbidimetry or ELISA, HDL-associated lipids were quantified enzymatically. To get an integrated measure of HDL quantity and quality, we assessed several metrics of HDL function, including cholesterol efflux capacity, anti-oxidative and anti-inflammatory activities using apoB-depleted serum from study participants.In our study, we observed that the HDL associated acute phase protein serum amyloid A (SAA was significantly increased in AMD patients (p<0.01, whereas all other assessed apolipoproteins including ApoA-I, apoA-II, apoC-II, apoC-III and apoE as well as major HDL associated lipids were not altered. HDL efflux capacity, anti-oxidative capacity and arylesterase activity were not different in AMD patients when compared with the control group. The ability of apoB-depleted serum to inhibit monocyte NF-κB expression was significantly improved in AMD patients (mean difference (MD -5.6, p<0.01. Moreover, lipoprotein-associated phospholipase A2 activity, a marker of vascular inflammation, was decreased in AMD subjects (MD -24.1, p<0.01.The investigated metrics of HDL composition and HDL function were not associated with exudative AMD in this study, despite an increased content of HDL associated SAA in AMD patients. Unexpectedly, anti-inflammatory activity of apoB-depleted serum was even increased in our study. Our data suggest that the investigated parameters of serum HDL function showed no

  6. Average-Time Games on Timed Automata

    OpenAIRE

    Jurdzinski, Marcin; Trivedi, Ashutosh

    2009-01-01

    An average-time game is played on the infinite graph of configurations of a finite timed automaton. The two players, Min and Max, construct an infinite run of the automaton by taking turns to perform a timed transition. Player Min wants to minimise the average time per transition and player Max wants to maximise it. A solution of average-time games is presented using a reduction to average-price game on a finite graph. A direct consequence is an elementary proof of determinacy for average-tim...

  7. Moderating Effect of Age on the Link of Emotional Intelligence and Mental Health among High School Students

    Science.gov (United States)

    Shabani, Jafar; Hassan, Siti Aishah; Ahmad, Aminah; Baba, Maznah

    2011-01-01

    This study examined whether Emotional Intelligence (EI) can be considered as predictor for mental health and explored also the moderating effect of age on the link between EI with mental health among high school students. The participants in the study included 10th, 11th, and 12th grade students from 8 public high schools in Gorgan City, north of…

  8. Effects of Lawsonia intracellularis on Average Daily Gain in finisher pigs

    DEFF Research Database (Denmark)

    Johansen, M.; Nielsen, M.; Dahl, J.;

    Lawsonia intracellularis (LI) is the causative agent of porcine proliferative enteropathy1, a disease that is found with high prevalence in all countries with industrial pig production. The infection is known to cause disease in different age groups. In pigs between 6 to 20 weeks of age the endem...... form called Porcine Intestinal Andenomatosis (PIA) is predominant. The clinical signs are diarrhoea, ill-thriftiness and wasting. The objective of this study was to estimate the impact of LI detected in faeces on Average Daily Gain (ADG) in grower-finisher pigs....

  9. Nutritional Status and Age at Menarche on Female Students of Junior High School

    Science.gov (United States)

    Juliyatmi, Rihul Husnul; Handayani, Lina

    2015-01-01

    Menarche is the first menstrual period as one of the sign of puberty. There are many factors may affect the age at menarche such as nutritional status, genetic, environmental conditions, socioeconomic status, and education. The purpose of this research is to determine the relationship between nutritional status and age of menarche on female…

  10. High-dose vitamin A supplementation administered with vaccinations after 6 months of age

    DEFF Research Database (Denmark)

    Fisker, Ane Bærent; Bale, Carlito; Jørgensen, Mathias Jul

    2013-01-01

    WHO recommends vitamin A supplementation (VAS) at vaccination contacts after six months of age. The effect of this recommendation on mortality has not been evaluated.......WHO recommends vitamin A supplementation (VAS) at vaccination contacts after six months of age. The effect of this recommendation on mortality has not been evaluated....

  11. Functional outcome at school age of preterm-born children treated with high-dose dexamethasone

    NARCIS (Netherlands)

    Hitzert, Marrit M.; Van Braeckel, Koenraad N. A.; de Bok, Marijn; Maathuis, Carel G. B.; Roze, Elise; Bos, Arend F.

    2014-01-01

    Background: Postnatal dexamethasone (DXM) treatment is associated with adverse motor outcome. It is largely unknown as to what extent functional outcome at school age is affected. Aims: Our first aim was to determine motor, cognitive, and behavioural outcome at school age of preterm-born children tr

  12. Serotonin Mediates a Learned Increase in Attraction to High Concentrations of Benzaldehyde in Aged "C. elegans"

    Science.gov (United States)

    Tsui, David; van der Kooy, Derek

    2008-01-01

    We utilized olfactory-mediated chemotaxis in "Caenorhabditis elegans" to examine the effect of aging on information processing and animal behavior. Wild-type (N2) young adults (day 4) initially approach and eventually avoid a point source of benzaldehyde. Aged adult animals (day 7) showed a stronger initial approach and a delayed avoidance to…

  13. Maternal death after oocyte donation at high maternal age: Case report

    NARCIS (Netherlands)

    J.M. Schutte (Joke); N.W.E. Schuitemaker (Nico); E.A.P. Steegers (Eric); J. van Roosmalen (Jos)

    2008-01-01

    textabstractBackground. The percentage of women giving birth after the age of 35 increased in many western countries. The number of women remaining childless also increased, mostly due to aging oocytes. The method of oocyte donation offers the possibility for infertile older women to become

  14. Maternal death after oocyte donation at high maternal age: Case report

    NARCIS (Netherlands)

    J.M. Schutte (Joke); N.W.E. Schuitemaker (Nico); E.A.P. Steegers (Eric); J. van Roosmalen (Jos)

    2008-01-01

    textabstractBackground. The percentage of women giving birth after the age of 35 increased in many western countries. The number of women remaining childless also increased, mostly due to aging oocytes. The method of oocyte donation offers the possibility for infertile older women to become pregnant

  15. Behavior problems at ages 6 and 11 and high school academic achievement: longitudinal latent variable modeling.

    Science.gov (United States)

    Breslau, Naomi; Breslau, Joshua; Miller, Elizabeth; Raykov, Tenko

    2011-02-28

    Previous studies documented long-run effects of behavior problems at the start of school on academic achievement. However, these studies did not examine whether the observed effects of early behavior problems are explained by more proximate behavior problems, given the tendency of children's behavior problems to persist. Latent variable modeling was applied to estimate the effects of behavior problems at ages 6 and 11 on academic achievement at age 17, using data from a longitudinal study (n=823). Behavior problems at ages 6 and 11, each stage independently of the other, predicted lower math and reading test scores at age 17, controlling for intelligence quotient (IQ), birth weight, maternal characteristics, family and community environment, and taking into account behavior problems at age 17. Behavior problems at the start of school, independent of later behavior problems, exert lingering effects on achievement by impeding the acquisition of cognitive skills that are the foundation for later academic progress.

  16. Studies on relationship of overweight and obesity with high blood pressure and high HCY in young and middle-aged adults

    Directory of Open Access Journals (Sweden)

    Wen-dong YANG

    2014-04-01

    Full Text Available Objective: To investigate the correlation between high blood pressure, high HCY and overweight as well as obesity in young and middle-aged adults by observing BMI and high HCY levels. Methods: To investigate BMI, blood pressure and HCY levels of 750 young and middle-aged adults, and to make statistical analysis according to the groups. Results: Proportion of overweight and obesity was 31.07% and 12.13% in 750 young and middle-aged adults. Proportion of overweight and obesity was higher in males than in females. (P<0.01. In total subjects, proportion of hypertension and high homocysteinemia were 17.07% and 9.73% , while proportion of hypertension and high homocysteinemia of overweight and obesity were 28.09% (91/324 and 19.75% (64/324, and they were significantly higher than the normal group (P<0.01. Blood pressure (systolic blood pressure, diastolic blood pressure and serum HCY levels were positively correlated with BMI (r=0.639,0.515,0.497,P<0.01. Conclusions: Over half Young and middle-aged adults, especially males, were overweight or obesity, high blood pressure and high HCY levels were correlated with BMI, high incidence of hypertension and hyperlipidemia HCY with overweight and obesity should be actively combat.

  17. Vibratory perception threshold in young and middle-aged patients at high risk of knee osteoarthritis compared to controls

    DEFF Research Database (Denmark)

    Thorlund, Jonas Bloch; Shakoor, Najia; Ageberg, Eva

    2012-01-01

    Vibratory perception threshold (VPT) is impaired in patients with knee osteoarthritis (OA). It is, however, not known if sensory deficits precede or follow as a consequence of OA. The aim of this study was to investigate VPT in 2 independent groups of patients with high risk of future OA (young a...... anterior cruciate ligament [ACL]-injured patients and middle-aged meniscectomized patients) and compare them to age-matched controls....

  18. Averaging and sampling for magnetic-observatory hourly data

    Directory of Open Access Journals (Sweden)

    J. J. Love

    2010-11-01

    Full Text Available A time and frequency-domain analysis is made of the effects of averaging and sampling methods used for constructing magnetic-observatory hourly data values. Using 1-min data as a proxy for continuous, geomagnetic variation, we construct synthetic hourly values of two standard types: instantaneous "spot" measurements and simple 1-h "boxcar" averages. We compare these average-sample types with others: 2-h average, Gaussian, and "brick-wall" low-frequency-pass. Hourly spot measurements provide a statistically unbiased representation of the amplitude range of geomagnetic-field variation, but as a representation of continuous field variation over time, they are significantly affected by aliasing, especially at high latitudes. The 1-h, 2-h, and Gaussian average-samples are affected by a combination of amplitude distortion and aliasing. Brick-wall values are not affected by either amplitude distortion or aliasing, but constructing them is, in an operational setting, relatively more difficult than it is for other average-sample types. It is noteworthy that 1-h average-samples, the present standard for observatory hourly data, have properties similar to Gaussian average-samples that have been optimized for a minimum residual sum of amplitude distortion and aliasing. For 1-h average-samples from medium and low-latitude observatories, the average of the combination of amplitude distortion and aliasing is less than the 5.0 nT accuracy standard established by Intermagnet for modern 1-min data. For medium and low-latitude observatories, average differences between monthly means constructed from 1-min data and monthly means constructed from any of the hourly average-sample types considered here are less than the 1.0 nT resolution of standard databases. We recommend that observatories and World Data Centers continue the standard practice of reporting simple 1-h-average hourly values.

  19. Maternal death after oocyte donation at high maternal age: case report

    Directory of Open Access Journals (Sweden)

    Steegers Eric AP

    2008-12-01

    Full Text Available Abstract Background The percentage of women giving birth after the age of 35 increased in many western countries. The number of women remaining childless also increased, mostly due to aging oocytes. The method of oocyte donation offers the possibility for infertile older women to become pregnant. Gestation after oocyte-donation-IVF, however, is not without risks for the mother, especially at advanced age. Case presentation An infertile woman went abroad for oocyte-donation-IVF, since this treatment is not offered in The Netherlands after the age of 45. The first oocyte donation treatment resulted in multiple gestation, but was ended by induced abortion: the woman could not cope with the idea of being pregnant with twins. During the second pregnancy after oocyte donation, at the age of 50, she was mentally more stable. The pregnancy, again a multiple gestation, was uneventful until delivery. Immediately after delivery the woman had hypertension with nausea and vomiting. A few hours later she had an eclamptic fit. HELLP-syndrome was diagnosed. She died due to cerebral haemorrhage. Conclusion In The Netherlands, the age limit for women receiving donor oocytes is 45 years and commercial oocyte donation is forbidden by law. In other countries there is no age limit, the reason why some women are going abroad to receive the treatment of their choice. Advanced age, IVF and twin pregnancy are all risk factors for pre-eclampsia, the leading cause of maternal death in The Netherlands. Patient autonomy is an important ethical principle, but doctors are also bound to the principle of 'not doing harm', and do have the right to refuse medical treatment such as IVF-treatment. The discussion whether women above 50 should have children is still not closed. If the decision is made to offer this treatment to a woman at advanced age, the doctor should counsel her intensively about the risks before treatment is started.

  20. 一维高效动态负载平衡方法:多层均权法%High Efficient One Dimensional Dynamical Load Balancing Method: Multilevel Averaging Weight Method

    Institute of Scientific and Technical Information of China (English)

    莫则尧

    2001-01-01

    A Multilevel Averaging Weight (MAW) dynamic load balancing method suitable for both synchronous and heterogeneous parallel computing environments is presented in this paper to solve the one-dimensional dynamic load imbalance problems arising from the parallel Lagrange numerical simulation of multiple matters non-steady fluid dynamics. At first, a one-dimensional load imbalance model is designed to simplify the theoretical analysis for the robustness of MAW method. For this model, the defined domain is uniformly differenced into grid cells, and every grid cells is assumed to be processed with different CPU time. Given P processors, it is required to find the efficient domain decomposition strategy which can keep the loads among different subdomains assigned to individual processors balanced. Secondly, we present a load balancing method, Averaging Weight (AW) method. The theoretical analysis shows that, while the number the processors is equal to 2, AW method is very efficient to adjust the system form a very imbalanced state to a very balanced state in 2—4 iterations. It is unfortunately that this conclusion can not be generalized to be suitable for larger number of processors. In further, inherited form the idea of the AW method, we designed another load balancing method, Multilevel Averaging Weight method. The similar theoretical analysis shows that this method can adjust the load to be balanced in ClogP iterations for any number of processors, where P is the number of processors and C is the iterations using AW method while P=2. This result is usually enough to efficiently track fluctuations in the load imbalance as the parallel numerical simulation progresses. Moreover, both AW and MAW method are all suitable for both homogeneous and heterogeneous parallel computing environments. Thirdly, we organize the numerical experiments for three types of load balancing models, and gain the same conclusions coincided with that of the theoretical analysis. At last, we

  1. Aging- and task-related resilience decline is linked to food responsiveness in highly social honey bees.

    Science.gov (United States)

    Speth, Martin T; Kreibich, Claus D; Amdam, Gro V; Münch, Daniel

    2015-05-01

    Conventional invertebrate models of aging have provided striking examples for the influence of food- and nutrient-sensing on lifespan and stress resilience. On the other hand, studies in highly social insects, such as honey bees, have revealed how social context can shape very plastic life-history traits, for example flexible aging dynamics in the helper caste (workers). It is, however, not understood how food perception and stress resilience are connected in honey bee workers with different social task behaviors and aging dynamics. To explore this linkage, we tested if starvation resilience, which normally declines with age, depends on food responsiveness in honey bees. We studied two typically non-senesced groups of worker bees with different social task behaviors: mature nurses (caregivers) and mature foragers (food collectors). In addition, we included a group of old foragers for which functional senescence is well-established. Bees were individually scored for their food perception by measuring the gustatory response to different sucrose concentrations. Subsequently, individuals were tested for survival under starvation stress. We found that starvation stress resilience, but not gustatory responsiveness differed between workers with different social task behaviors (mature nurses vs. mature foragers). In addition starvation stress resilience differed between foragers with different aging progressions (mature foragers vs. old foragers). Control experiments confirmed that differences in starvation resilience between mature nurses and mature foragers were robust against changing experimental conditions, such as water provision and activity. For all worker groups we established that individuals with low gustatory responsiveness were more resilient to starvation stress. Finally, for the group of rapidly aging foragers we found that low food responsiveness was linked to a delayed age-related decline in starvation resilience. Our study highlights associations between

  2. The association between etanercept serum concentration and psoriasis severity is highly age-dependent.

    Science.gov (United States)

    Detrez, Iris; Van Steen, Kristel; Segaert, Siegfried; Gils, Ann

    2017-06-01

    The association between etanercept serum concentration and psoriasis disease severity is poorly investigated, and currently etanercept serum concentration monitoring that is aiming to optimize the psoriasis treatment lacks evidence. In this prospective study, we investigated the relation between etanercept exposure and disease severity via measuring etanercept concentrations at five consecutive time points in 56 psoriasis patients. Disease severity assessments included the Psoriasis Area and Severity Index (PASI), body surface area (BSA) and Physician Global Assessment (PGA), and etanercept and anti-etanercept antibody concentrations were determined every 3 months for a period of 1 year. The present study demonstrated that the association between etanercept concentration and psoriasis severity is age-dependent: when patients were stratified into three groups, patients in the youngest age group (-50 years) showed a lower PASI at a higher etanercept concentration (β = -0.26), whereas patients in the oldest age group (+59 years) showed the opposite trend (β =0.22). Similar age effects were observed in the relation of etanercept concentration with BSA (P=0.02) and PGA (P=0.02). The influence of age and length of time in therapy on the etanercept concentration-disease severity relation was unaffected by body mass index (BMI) or any other possible confounder. Incidence of anti-etanercept antibodies was low (2%). The age-dependent relation between etanercept serum concentrations is both unexpected and intriguing and needs further investigation. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  3. WIDTHS AND AVERAGE WIDTHS OF SOBOLEV CLASSES

    Institute of Scientific and Technical Information of China (English)

    刘永平; 许贵桥

    2003-01-01

    This paper concerns the problem of the Kolmogorov n-width, the linear n-width, the Gel'fand n-width and the Bernstein n-width of Sobolev classes of the periodicmultivariate functions in the space Lp(Td) and the average Bernstein σ-width, averageKolmogorov σ-widths, the average linear σ-widths of Sobolev classes of the multivariatequantities.

  4. DS-777 Average Annual Recharge, 2000 to 2009, in inches estimated from the SOil WATer (SOWAT) Balance Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  5. DS-777 Average Annual Irrigation Withdrawals, 2000 to 2009, in inches estimated from the Soil Water Balance (SWB) Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget-components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  6. DS-777 Average Annual Precipitation Data, 1940 to 1949, in inches estimated from an Inverse-Distance-Weighted (IDW) interpolation for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget-components geodatabase contains selected data from maps in the,"Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  7. DS-777 Average Annual Actual Evapotranspiration, 1940 to 1949, in inches estimated from the Soil Water Balance (SWB) Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  8. DS-777 Average Annual Irrigation Withdrawals, 2000 to 2009, in inches, estimated from the Soil WATer (SOWAT) Balance Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  9. DS-777 Average Annual Actual Evapotranspiration, 2000 to 2009, in inches estimated from the Simplified-Surface-Energy-Balance (SSEB) Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  10. DS-777 Average Annual Recharge, 2000 to 2009, in inches estimated from the Soil Water Balance (SWB) Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  11. DS-777 Average Annual Precipitation Data, 2000 to 2009, in inches estimated from an Inverse-Distance-Weighted (IDW) interpolation, for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget-components geodatabase contains selected data from maps in the,"Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  12. DS-777 Average Annual Actual Evapotranspiration, 2000 to 2009, in inches estimated from the Soil Water Balance (SWB) Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the,"Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  13. DS-777 Average Annual Recharge, 1940 to 1949, in inches estimated from the Soil Water Balance (SWB) Model for the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The water-budget components geodatabase contains selected data from maps in the, "Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940...

  14. DS-777 Thickness-Weighted Average of Hydraulic Conductivity and Specific Yield for the Northern High Plains Groundwater-Flow Model in Parts of Colorado, Kansas, Nebraska, South Dakota, and Wyoming

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is one of many developed in support of The High Plains Groundwater Availability Project and the U.S. Geological Survey Data Series Report: Geodatabase...

  15. Stochastic averaging of quasi-Hamiltonian systems

    Institute of Scientific and Technical Information of China (English)

    朱位秋

    1996-01-01

    A stochastic averaging method is proposed for quasi-Hamiltonian systems (Hamiltonian systems with light dampings subject to weakly stochastic excitations). Various versions of the method, depending on whether the associated Hamiltonian systems are integrable or nonintegrable, resonant or nonresonant, are discussed. It is pointed out that the standard stochastic averaging method and the stochastic averaging method of energy envelope are special cases of the stochastic averaging method of quasi-Hamiltonian systems and that the results obtained by this method for several examples prove its effectiveness.

  16. NOAA Average Annual Salinity (3-Zone)

    Data.gov (United States)

    California Department of Resources — The 3-Zone Average Annual Salinity Digital Geography is a digital spatial framework developed using geographic information system (GIS) technology. These salinity...

  17. A Stress-Induced Martensitic Transformation in Aged Ti49Ni51 Alloy after High-Velocity Impact

    Directory of Open Access Journals (Sweden)

    Yingying Zhu

    2016-06-01

    Full Text Available The effects of a high-velocity impact on the microstructure, phase transformation and mechanical property of aged Ti49Ni51 alloy are investigated. The transformation behavior and microstructure along the impact direction after impact emerge with regionalization characteristics, including a deformed region near the crater (0–4 mm and an un-deformed region of the distal crater (5–6 mm. Stress-induced martensite is the main deformation mechanism in the deforming region of aged Ti49Ni51 alloy under high-velocity impact.

  18. Microstructure and high temperature stability of age hardenable AA2219 aluminium alloy modified by Sc, Mg and Zr additions

    Energy Technology Data Exchange (ETDEWEB)

    Naga Raju, P. [Metallurgical and Materials Engineering Department, IIT-Madras, Chennai 600036 (India)], E-mail: puvvala_nagaraju@yahoo.com; Srinivasa Rao, K. [Metallurgical Engineering Department, Andhra University, Visakapatnam 530003 (India); Reddy, G.M. [Defence Metallurgical Research Laboratory, Hyderabad 500258 (India); Kamaraj, M.; Prasad Rao, K. [Metallurgical and Materials Engineering Department, IIT-Madras, Chennai 600036 (India)

    2007-08-25

    The present work pertains to the improvement of high temperature stability of age hardenable AA2219 aluminium-copper (6.3%) alloy. Addition of scandium, magnesium and zirconium to the base metal AA2219 was adopted to improve this high temperature stability. These additions were systematically varied by preparing alloys of different composition using gas tungsten arc melting. Long time ageing studies and impression creep technique were used to study the high temperature stability of the alloys. These modified compositions of the alloy resulted in fine equiaxed grains, refined eutectics, large number of high temperature stable and finer precipitates. Among all the compositions, 0.8% Sc + 0.45% Mg + 0.2% Zr addition was found to be significant in improving the high temperature stability of AA2219 alloy. This may be attributed to the possible microstructural changes, solute enrichment of the matrix and pinning of the grain boundaries by the finer precipitates.

  19. Pregnancy-specific stress, preterm birth, and gestational age among high-risk young women.

    Science.gov (United States)

    Cole-Lewis, Heather J; Kershaw, Trace S; Earnshaw, Valerie A; Yonkers, Kimberly Ann; Lin, Haiqun; Ickovics, Jeannette R

    2014-09-01

    There is evidence that pregnancy-specific stress is associated with preterm birth. The purpose of this study is to examine the association between change in pregnancy-specific stress over the course of pregnancy and birth outcomes (i.e., preterm birth and gestational age) in an understudied but vulnerable group using a theoretically derived model. Multivariate linear and logistic regression techniques were used to examine the association between pregnancy-specific stress (measured in second and third trimester) and length of gestation (i.e., preterm birth and gestational age) among a sample of 920 Black and/or Latina adolescent and young women. Second trimester pregnancy-specific stress was not associated with preterm birth or gestational age. Third trimester pregnancy-specific stress was associated with preterm birth but not with gestational age. Change in pregnancy-specific stress between second and third trimester was significantly associated with increased likelihood of preterm delivery and shortened gestational age, even after controlling for important biological, behavioral, psychological, interpersonal, and sociocultural risk factors. Findings emphasize the importance of measuring pregnancy-specific stress across pregnancy, as the longitudinal change from second to third trimester was significantly associated with length of gestation measured both as a dichotomous variable (preterm birth) and a continuous variable (gestational age). Furthermore, this is the first study to observe the association of pregnancy-specific stress with length of gestation in this understudied population-unique in age, race, and ethnicity. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  20. Dynamic Multiscale Averaging (DMA) of Turbulent Flow

    Energy Technology Data Exchange (ETDEWEB)

    Richard W. Johnson

    2012-09-01

    A new approach called dynamic multiscale averaging (DMA) for computing the effects of turbulent flow is described. The new method encompasses multiple applications of temporal and spatial averaging, that is, multiscale operations. Initially, a direct numerical simulation (DNS) is performed for a relatively short time; it is envisioned that this short time should be long enough to capture several fluctuating time periods of the smallest scales. The flow field variables are subject to running time averaging during the DNS. After the relatively short time, the time-averaged variables are volume averaged onto a coarser grid. Both time and volume averaging of the describing equations generate correlations in the averaged equations. These correlations are computed from the flow field and added as source terms to the computation on the next coarser mesh. They represent coupling between the two adjacent scales. Since they are computed directly from first principles, there is no modeling involved. However, there is approximation involved in the coupling correlations as the flow field has been computed for only a relatively short time. After the time and spatial averaging operations are applied at a given stage, new computations are performed on the next coarser mesh using a larger time step. The process continues until the coarsest scale needed is reached. New correlations are created for each averaging procedure. The number of averaging operations needed is expected to be problem dependent. The new DMA approach is applied to a relatively low Reynolds number flow in a square duct segment. Time-averaged stream-wise velocity and vorticity contours from the DMA approach appear to be very similar to a full DNS for a similar flow reported in the literature. Expected symmetry for the final results is produced for the DMA method. The results obtained indicate that DMA holds significant potential in being able to accurately compute turbulent flow without modeling for practical

  1. Effect of high pressure treatment on the aging characteristics of Chinese liquor as evaluated by electronic nose and chemical analysis

    Science.gov (United States)

    Zhu, S. M.; Xu, M. L.; Ramaswamy, H. S.; Yang, M. Y.; Yu, Y.

    2016-08-01

    Several high pressure (HP) treatments (100–400 MPa 15 and 30 min) were applied to Chinese “Junchang” liquor, and aging characteristics of the liquor were evaluated. Results from the principal component analysis and the discriminant factor analysis of E-Nose demonstrated that HP treatment at 300 and 400 MPa resulted in significant (p natural aging process of Chinese liquor. However, HP treatment caused a slight increase in solid content, which might be somewhat undesirable. Sensory evaluation results confirmed that favorable changes in color and flavor of Chinese liquor were induced by HP treatment; however, overall gaps still existed between the quality of treated and six-year aged samples. HP treatment demonstrated a potential to accelerate the natural aging process for Chinese liquor, but long term studies may be needed further to realize the full potential.

  2. Stream water age distributions controlled by storage dynamics and nonlinear hydrologic connectivity: Modeling with high-resolution isotope data.

    Science.gov (United States)

    Soulsby, C; Birkel, C; Geris, J; Dick, J; Tunaley, C; Tetzlaff, D

    2015-09-01

    To assess the influence of storage dynamics and nonlinearities in hydrological connectivity on time-variant stream water ages, we used a new long-term record of daily isotope measurements in precipitation and streamflow to calibrate and test a parsimonious tracer-aided runoff model. This can track tracers and the ages of water fluxes through and between conceptual stores in steeper hillslopes, dynamically saturated riparian peatlands, and deeper groundwater; these represent the main landscape units involved in runoff generation. Storage volumes are largest in groundwater and on the hillslopes, though most dynamic mixing occurs in the smaller stores in riparian peat. Both streamflow and isotope variations are generally well captured by the model, and the simulated storage and tracer dynamics in the main landscape units are consistent with independent measurements. The model predicts that the average age of stream water is ∼1.8 years. On a daily basis, this varies between ∼1 month in storm events, when younger waters draining the hillslope and riparian peatland dominates, to around 4 years in dry periods when groundwater sustains flow. This variability reflects the integration of differently aged water fluxes from the main landscape units and their mixing in riparian wetlands. The connectivity between these spatial units varies in a nonlinear way with storage that depends upon precipitation characteristics and antecedent conditions. This, in turn, determines the spatial distribution of flow paths and the integration of their contrasting nonstationary ages. This approach is well suited for constraining process-based modeling in a range of northern temperate and boreal environments.

  3. An epidemiological study of diabetes mellitus amongst high risk age group population in urban and Rural areas of kanpur

    Directory of Open Access Journals (Sweden)

    Nadeem Ahmad

    2003-12-01

    Full Text Available Research Question : - What is the magnitude of Diabetes mellitus in the urban and rural areas of Kanpur.Objectives:To study the prevalence of diabetes mellitus amongst high risk age group population in urban and rural areas of Kanpur.To compare the magnitude of problem of diabetes mellitus between urban and rural areas of Kanpur.To study the possible associates and socio-demographic variables related to diabetes mellitus.Study Design : Cross sectional study.Setting : The study was performed on three thousand population each in urban and rural areas of Kanpur.Participants : High risk age group population i.e. 45 years and above.Study variables : Age, Sex. impaired glucose tolerance. Body mass index, Education, Working status. Social class, family history of diabetes.Statistical analysis : Chi-square lest, percentagesResults From a total of 676 persons of high risk age group i.e. 45 years and above, the overall prevalence of diabetes mellitus in the study areas was observed lobe 7. l%with 9.94% in urban and 3.61% in rural areas, the maximum percetage of diabetes cases (41.66% was in the age group of 56-60 years. Higher prevalence of diabetes was observed in the obese (56.25% and sedentary (87.5% persons. The family history' of diabetes mellitus was present in (35.41% of diabetes mellitus cases.

  4. Average Transmission Probability of a Random Stack

    Science.gov (United States)

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  5. Average sampling theorems for shift invariant subspaces

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The sampling theorem is one of the most powerful results in signal analysis. In this paper, we study the average sampling on shift invariant subspaces, e.g. wavelet subspaces. We show that if a subspace satisfies certain conditions, then every function in the subspace is uniquely determined and can be reconstructed by its local averages near certain sampling points. Examples are given.

  6. Testing linearity against nonlinear moving average models

    NARCIS (Netherlands)

    de Gooijer, J.G.; Brännäs, K.; Teräsvirta, T.

    1998-01-01

    Lagrange multiplier (LM) test statistics are derived for testing a linear moving average model against an additive smooth transition moving average model. The latter model is introduced in the paper. The small sample performance of the proposed tests are evaluated in a Monte Carlo study and compared

  7. Averaging Einstein's equations : The linearized case

    NARCIS (Netherlands)

    Stoeger, William R.; Helmi, Amina; Torres, Diego F.

    2007-01-01

    We introduce a simple and straightforward averaging procedure, which is a generalization of one which is commonly used in electrodynamics, and show that it possesses all the characteristics we require for linearized averaging in general relativity and cosmology for weak-field and perturbed FLRW situ

  8. Averaging Einstein's equations : The linearized case

    NARCIS (Netherlands)

    Stoeger, William R.; Helmi, Amina; Torres, Diego F.

    We introduce a simple and straightforward averaging procedure, which is a generalization of one which is commonly used in electrodynamics, and show that it possesses all the characteristics we require for linearized averaging in general relativity and cosmology for weak-field and perturbed FLRW

  9. Average excitation potentials of air and aluminium

    NARCIS (Netherlands)

    Bogaardt, M.; Koudijs, B.

    1951-01-01

    By means of a graphical method the average excitation potential I may be derived from experimental data. Average values for Iair and IAl have been obtained. It is shown that in representing range/energy relations by means of Bethe's well known formula, I has to be taken as a continuously changing fu

  10. Average Transmission Probability of a Random Stack

    Science.gov (United States)

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  11. Aging phenomena in high-Si steels studied by internal friction

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, D. [Department of Metallurgy and Materials Science, Ghent University, Technologiepark 903, B-9052 Gent (Belgium) and Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)]. E-mail: Daniel.Ruiz@UGent.be; Rivera-Tovar, J.L. [Department of Metallurgy and Materials Science, Ghent University, Technologiepark 903, B-9052 Gent (Belgium); Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, A.P. 149-F, 66451 San Nicolas de los Garza, N.L. (Mexico); Segers, D. [Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Vandenberghe, R.E. [Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Houbaert, Y. [Department of Metallurgy and Materials Science, Ghent University, Technologiepark 903, B-9052 Gent (Belgium)

    2006-12-20

    Si-steels with various Si-contents (1.9-5.6 wt.%) have been analyzed by internal friction and compared with an ultra-low carbon steel. Measurements have been carried out immediately after different thermomechanical treatments to study a believed aging phenomenon. Adding Si lowers the Snoek peak of carbon and produces a new peak associated to the formation of Si-C pairs. For Si contents higher than 4.6 wt.%, another peak appears at very low frequencies, which can be attributed to a Zener relaxation of Si-atom pairs. A room-temperature aging effect has been detected in the Si-steels, but not in the ultra-low carbon steel. This aging is caused by the migration of C atoms to the structural defects and by formation of short-range order in the Fe-Si solution.

  12. New results on averaging theory and applications

    Science.gov (United States)

    Cândido, Murilo R.; Llibre, Jaume

    2016-08-01

    The usual averaging theory reduces the computation of some periodic solutions of a system of ordinary differential equations, to find the simple zeros of an associated averaged function. When one of these zeros is not simple, i.e., the Jacobian of the averaged function in it is zero, the classical averaging theory does not provide information about the periodic solution associated to a non-simple zero. Here we provide sufficient conditions in order that the averaging theory can be applied also to non-simple zeros for studying their associated periodic solutions. Additionally, we do two applications of this new result for studying the zero-Hopf bifurcation in the Lorenz system and in the Fitzhugh-Nagumo system.

  13. Analogue Divider by Averaging a Triangular Wave

    Science.gov (United States)

    Selvam, Krishnagiri Chinnathambi

    2017-08-01

    A new analogue divider circuit by averaging a triangular wave using operational amplifiers is explained in this paper. The triangle wave averaging analog divider using operational amplifiers is explained here. The reference triangular waveform is shifted from zero voltage level up towards positive power supply voltage level. Its positive portion is obtained by a positive rectifier and its average value is obtained by a low pass filter. The same triangular waveform is shifted from zero voltage level to down towards negative power supply voltage level. Its negative portion is obtained by a negative rectifier and its average value is obtained by another low pass filter. Both the averaged voltages are combined in a summing amplifier and the summed voltage is given to an op-amp as negative input. This op-amp is configured to work in a negative closed environment. The op-amp output is the divider output.

  14. High Age Predicts Low Referral of Hyperthyroid Patients to Specialized Hospital Departments

    DEFF Research Database (Denmark)

    Carlé, Allan; Pedersen, Inge Bülow; Perrild, Hans

    2013-01-01

    , and analyzed how referral depended on subtype of disease, sex, age, and degree of biochemical hyperthyroidism. Results: In a 4-year period, 1,032 hyperthyroid patients were diagnosed at primary care offices, and 435 of these (42.2%) were referred to specialized units, 92 patients had hyperthyroidism diagnosed...... in other hospital departments (referral: 43, 46.7%), and 24 patients had hyperthyroidism diagnosed at the specialized unit after referral for other diseases. Patients suffering from Graves' disease (GD; n=474, median age=65.8 years) were referred more often (odds ratio=1.7 [95% confidence interval 1...

  15. Extended multiplexing of TMT labeling reveals age and high fat diet specific proteome changes in mouse epididymal adipose tissue.

    Science.gov (United States)

    Plubell, Deanna L; Wilmarth, Phillip A; Zhao, Yuqi; Fenton, Alexandra M; Minnier, Jessica; Reddy, Ashok P; Klimek, John; Yang, Xia; David, Larry L; Pamir, Nathalie

    2017-03-21

    The lack of high-throughput methods to analyze the adipose tissue protein composition limits our understanding of the protein networks responsible for age and diet related metabolic response. We have developed an approach using multiple-dimension liquid chromatography tandem mass spectrometry and extended multiplexing (24 biological samples) with TMT labeling to analyze proteomes of epididymal adipose tissues isolated from mice fed either low or high fat diet for a short or a long-term, and from mice that aged on low vs. high fat diets. The peripheral metabolic health (as measured by body weight, adiposity, plasma fasting glucose, insulin, triglycerides, total cholesterol levels, and glucose and insulin tolerance tests) deteriorated with diet and advancing age, with long-term high fat diet exposure being the worst. In response to short-term high fat diet, 43 proteins representing lipid metabolism (e.g., AACS, ACOX1, ACLY) and red-ox pathways (e.g., CPD2, CYP2E, SOD3) were significantly altered (FDR fat diet significantly altered 55 proteins associated with immune response (e.g., IGTB2, IFIT3, LGALS1) and rennin angiotensin system (e.g. ENPEP, CMA1, CPA3, ANPEP). Age-related changes on low fat diet significantly altered only 18 proteins representing mainly urea cycle (e.g., OTC, ARG1, CPS1), and amino acid biosynthesis (e.g., GMT, AKR1C6). Surprisingly, high fat diet driven age-related changes culminated with alterations in 155 proteins involving primarily the urea cycle (e.g., ARG1, CPS1), immune response/complement activation (e.g., C3, C4b, C8, C9, CFB, CFH, FGA), extracellular remodeling (e.g., EFEMP1, FBN1, FBN2, LTBP4, FERMT2, ECM1, EMILIN2, ITIH3) and apoptosis (e.g., YAP1, HIP1, NDRG1, PRKCD, MUL1) pathways. Using our adipose tissue tailored approach we have identified both age-related and high fat diet specific proteomic signatures highlighting a pronounced involvement of arginine metabolism in response to advancing age, and branched chain amino acid

  16. Features of high-speed and strength qualities development in young biathlonists aged 14–15 in the preparatory period

    Directory of Open Access Journals (Sweden)

    Artem Burla

    2015-04-01

    Full Text Available Purpose: to substantiate a methodology of high-speed and strength qualities development of young biathlonists aged 14–15 during the preparatory period. Material and Methods: young biathlonists aged 14–15 from control and experimental groups took part in the research. There were 12 athletes in each group. Pedagogical methods and methods of mathematical statistics were used in the work. Pedagogical methods of researches were used for level definition of high-speed and strength qualities development of young biathlonists. Results: reliable increase of motive qualities and polydynamometry results testing of young biathlonists from the experimental group due to implementation of the experimental methodology in the preparatory period is established. Conclusions: application of the developed complexes in the preparatory period in the experimental group of young biathlonists aged 14–15 allows to raise indices of motive qualities and polydynamometry testing statistically significantly.

  17. Relationships between feeding behavior and average daily gain in cattle

    Directory of Open Access Journals (Sweden)

    Bruno Fagundes Cunha Lage

    2013-12-01

    Full Text Available Several studies have reported relationship between eating behavior and performance in feedlot cattle. The evaluation of behavior traits demands high degree of work and trained manpower, therefore, in recent years has been used an automated feed intake measurement system (GrowSafe System ®, that identify and record individual feeding patterns. The aim of this study was to evaluate the relationship between feeding behavior traits and average daily gain in Nellore calves undergoing feed efficiency test. Date from 85 Nelore males was recorded during the feed efficiency test performed in 2012, at Centro APTA Bovinos de Corte, Instituto de Zootecnia, São Paulo State. Were analyzed the behavioral traits: time at feeder (TF, head down duration (HD, representing the time when the animal is actually eating, frequency of visits (FV and feed rate (FR calculated as the amount of dry matter (DM consumed by time at feeder (g.min-1. The ADG was calculated by linear regression of individual weights on days in test. ADG classes were obtained considering the average ADG and standard deviation (SD being: high ADG (>mean + 1.0 SD, medium ADG (± 1.0 SD from the mean and low ADG (age at the middle of test as a covariate. Low gain animals remained 21.8% less time of head down than medium or high gain animals (P<0.05. Were observed significant effects of ADG class on FR (P<0.01, high ADG animals consumed more feed per time (g.min-1 than the low and medium ADG animals. No diferences were observed (P>0.05 among ADG classes for FV, indicating that these traits are not related to each other. These results shows that the ADG is related to the agility in eat food and not to the time spent in the bunk or to the number of visits in a range of 24 hours.

  18. Do Diurnal Aerosol Changes Affect Daily Average Radiative Forcing?

    Energy Technology Data Exchange (ETDEWEB)

    Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Michalsky, Joseph J.; Lantz, K.; Hodges, G. B.

    2013-06-17

    Strong diurnal variability of aerosol has been observed frequently for many urban/industrial regions. How this variability may alter the direct aerosol radiative forcing (DARF), however, is largely unknown. To quantify changes in the time-averaged DARF, we perform an assessment of 29 days of high temporal resolution ground-based data collected during the Two-Column Aerosol Project (TCAP) on Cape Cod, which is downwind of metropolitan areas. We demonstrate that strong diurnal changes of aerosol loading (about 20% on average) have a negligible impact on the 24-h average DARF, when daily averaged optical properties are used to find this quantity. However, when there is a sparse temporal sampling of aerosol properties, which may preclude the calculation of daily averaged optical properties, large errors (up to 100%) in the computed DARF may occur. We describe a simple way of reducing these errors, which suggests the minimal temporal sampling needed to accurately find the forcing.

  19. Determining the optimal number of individual samples to pool for quantification of average herd levels of antimicrobial resistance genes in Danish pig herds using high-throughput qPCR

    DEFF Research Database (Denmark)

    Clasen, Julie; Mellerup, Anders; Olsen, John Elmerdahl

    2016-01-01

    The primary objective of this study was to determine the minimum number of individual fecal samples to pool together in order to obtain a representative sample for herd level quantification of antimicrobial resistance (AMR) genes in a Danish pig herd, using a novel high-throughput qPCR assay....... The secondary objective was to assess the agreement between different methods of sample pooling. Quantification of AMR was achieved using a high-throughput qPCR method to quantify the levels of seven AMR genes (ermB, ermF, sulI, sulII, tet(M), tet(O) and tet(W)). A large variation in the levels of AMR genes...

  20. Relationship between Tree Value, Diameter, and Age in High-Quality Sugar Maple (Acer saccharum) on the Menominee Reservation, Wisconsin

    Science.gov (United States)

    Daniel C. Dey; John Dwyer; Jan Wiedenbeck

    2017-01-01

    Guidelines for managing sugar maple-dominated forests by the single-tree selection method are well established and widely adopted. The forests of the Menominee Tribe in Wisconsin provide an opportunity to validate current guidelines by testing tree value and size/age relationships in forests that have substantially older and larger high-quality trees than can be found...

  1. Validation of a novel automatic sleep spindle detector with high performance during sleep in middle aged subjects

    DEFF Research Database (Denmark)

    Wendt, Sabrina Lyngbye; Christensen, Julie A. E.; Kempfner, Jacob

    2012-01-01

    Many of the automatic sleep spindle detectors currently used to analyze sleep EEG are either validated on young subjects or not validated thoroughly. The purpose of this study is to develop and validate a fast and reliable sleep spindle detector with high performance in middle aged subjects. An a...

  2. High-Frequency, Moderate-Intensity Training in Sedentary Middle-Aged Women.

    Science.gov (United States)

    Johannessen, S.; And Others

    1986-01-01

    The effects of a five-day-a-week, moderate-intensity aerobic training program were studied in previously sedentary middle-aged women. After 10 weeks of graduated-length sessions of continuous exercise, the subjects showed a 20 percent improvement in maximal oxygen uptake but no change in body weight or composition. Results are discussed.…

  3. Functional limitations linked to high body mass index, age and current pain in obese women.

    Science.gov (United States)

    Evers Larsson, U; Mattsson, E

    2001-06-01

    To describe functional limitations in obese women. Comparisons of functional limitations in obese women and in a normal-weight reference group regarding mobility, balance and housework transport. A large room with a corridor and staircase nearby. Fifty-seven consecutively selected obese female outpatients, mean age 44 y, body mass index (BMI) 37 kg.m(-2), and 22 voluntary references, mean age 49 y, BMI 22 kg.m(-2). Pain questionnaire (for background data); a new valid and reliable test protocol measuring activities of daily life (ADL), pain and exertion, heart rate, balance and speed. The patients had problems in performing 13 of 16 actions compared with the references (P-values between 0.05 and 0.001). They moved more slowly and had difficulties and /or pain and exertion in flexibility tasks, balancing, activities at floor level (bending and kneeling), climbing stairs and carrying groceries. BMI (P=0.002), age (P=0.02) and current pain (P=0.02) from the lower body predicted functional limitation. The functional test reflected functional limitations in obese women, revealing difficulties and perceived pain in ADL. The test protocol can be used to evaluate the effects of training or dieting. For clinical use we recommend considering BMI, age and current pain for use when individualizing advice on training.

  4. On the complex ageing characteristics of high-power LiFePO4/graphite battery cells cycled with high charge and discharge currents

    DEFF Research Database (Denmark)

    Groot, Jens; Swierczynski, Maciej Jozef; Stroe, Ana-Irina

    2015-01-01

    are demanding. The aim of the present work is to quantify the ageing in terms of capacity fade and impedance growth as a function of operating conditions typical to high-power automotive applications; high charge and discharge rate, elevated temperatures and wide state-of-charge windows. The cycle life of 34......Li-ion batteries are known to undergo complex ageing processes, where the operating conditions have a profound and non-linear effect on both calendar life and cycle life. This is especially a challenge for the automotive industry, where the requirements on product lifetime and reliability...... power-optimised LiFePO4/graphite cells was quantified by testing with charge and discharge rates between 1 and 4C-rate, temperatures between +23o C and +53o C, and a depth-of-discharge of either 100% or 60%. Although all cells show similar ageing pattern in general, the cycle life...

  5. Short-term high dose of quercetin and resveratrol alters aging markers in human kidney cells

    Directory of Open Access Journals (Sweden)

    Fatemeh Abharzanjani

    2017-01-01

    Full Text Available Background: Hyperglycemia-mediated oxidative stress implicates in etiology of kidney cell aging and diabetic nephropathy. We evaluated the effects of different doses of resveratrol and quercetin and their combination therapy on aging marker in human kidney cell culture under hyperglycemia condition. Methods: Human embryonic kidney cell (HEK-293 was cultured in Dulbecco's Modified Eagle Medium (DMEM containing 100 mM (18 mg/L for 24 h. The cells were treated with resveratrol (2.5, 5, 10 μm, quercetin (3, 6, 12 μm, and combination of these (R 2.5 μm, Q 3 μm and (R 5 μm, Q 6 μm and (R 10 μm, Q 12 μm for 48 h, and then, cells were lysed to access RNA and lysate. Results: The analysis of data showed that beta-galactosidase enzyme gene expression as an aging marker in all treatment groups has reduced in a dose-dependent manner. Gene expression of Sirtuin1 and thioredoxin (Trx in all treated groups in comparison to control group increased in a dose-dependent fashion. Trx interacting protein (TXNIP gene expression decreased in a dose-dependent manner in all treated groups, especially in resveratrol and combination therapy. Conclusions: According to the results of this research, quercetin, resveratrol, and especially combination treatments with increased expression levels of antioxidants, can reduce aging markers in HEK cell line in hyperglycemia conditions. These results lead us to use flavonoids such as resveratrol for anti-aging potential.

  6. Implications of the Eighth Joint National Committee Guidelines for the Management of High Blood Pressure for Aging Adults: Atherosclerosis Risk in Communities Study.

    Science.gov (United States)

    Miedema, Michael D; Lopez, Faye L; Blaha, Michael J; Virani, Salim S; Coresh, Josef; Ballantyne, Christie M; Folsom, Aaron R

    2015-09-01

    The recent 2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults from the Eight Joint National Committee Panel may significantly affect the aging US population. We performed a cross-sectional analysis of black and white participants in Atherosclerosis Risk in Communities who participated in the fifth study visit (2011-2013). Sitting blood pressure was calculated from the average of 3 successive readings taken after a 5-minute rest. Currently, prescribed antihypertensive medications were recorded by reviewing medication containers brought to the visit. Blood pressure control was defined using both the Seventh and Eighth Joint National Committee thresholds. Of 6088 participants (mean age, 75.6 [range, 66-90] years, 58.4% women; 23.2% black), 54.9% had either diabetes mellitus or chronic kidney disease. The prevalence of hypertension according to Seventh Joint National Committee thresholds was 81.9%, and 62.8% of the entire sample were at blood pressure goal. Using the Eighth Joint National Committee thresholds, 79.4% were at blood pressure goal (16.6% were reclassified as at-goal). Reclassification was higher for individuals with diabetes mellitus or chronic kidney disease (20.6%) when compared with individuals without either condition (11.6%). The use of antihypertensive medications in our cohort was high, with 75.0% prescribed at least 1 antihypertensive medication and 46.7% on ≥2 antihypertensive agents. In conclusion, in a US cohort of aging white and black individuals, ≈1 in 6 individuals were reclassified as having blood pressure at goal by Eighth Joint National Committee guidelines. Despite these less aggressive goals, >20% remain uncontrolled by the new criteria. © 2015 American Heart Association, Inc.

  7. A procedure to average 3D anatomical structures.

    Science.gov (United States)

    Subramanya, K; Dean, D

    2000-12-01

    Creating a feature-preserving average of three dimensional anatomical surfaces extracted from volume image data is a complex task. Unlike individual images, averages present right-left symmetry and smooth surfaces which give insight into typical proportions. Averaging multiple biological surface images requires careful superimposition and sampling of homologous regions. Our approach to biological surface image averaging grows out of a wireframe surface tessellation approach by Cutting et al. (1993). The surface delineating wires represent high curvature crestlines. By adding tile boundaries in flatter areas the 3D image surface is parametrized into anatomically labeled (homology mapped) grids. We extend the Cutting et al. wireframe approach by encoding the entire surface as a series of B-spline space curves. The crestline averaging algorithm developed by Cutting et al. may then be used for the entire surface. Shape preserving averaging of multiple surfaces requires careful positioning of homologous surface regions such as these B-spline space curves. We test the precision of this new procedure and its ability to appropriately position groups of surfaces in order to produce a shape-preserving average. Our result provides an average that well represents the source images and may be useful clinically as a deformable model or for animation.

  8. The nucleosynthetic history of elements in the Galactic disk: [X/Fe] - age relations from high-precision spectroscopy

    CERN Document Server

    Spina, L; Karakas, A I; Ramírez, I; Monroe, T R; Asplund, M; Yong, D

    2016-01-01

    Context: The chemical composition of stars is intimately linked to the Galaxy formation and evolution. Aims: We aim to trace the chemical evolution of the Galactic disk through the inspection of the [X/Fe]-age relations of 24 species from C to Eu. Methods: Using high-resolution and high-signal-to-noise UVES spectra of nine solar twins, we obtained precise estimates of stellar ages and chemical abundances. These determinations have been integrated with additional accurate age and abundance determinations from recent spectroscopic studies of solar twins existing in the literature, comprising superb abundances with 0.01~dex precision. Based on this data set, we outlined the [X/Fe]-age relations over a time interval of 10~Gyr. Results: We present the [X/Fe] - age relations for 24 elements (C, O, Na, Mg, Al, Si, S, K, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Ba, La, Ce, Nd, and Eu). Each different class of elements showed distinct evolution with time that relies on the different characteristics, rates and timesca...

  9. Incorporation of Copper Enhances the Anti-Ageing Property of Flame-Sprayed High-Density Polyethylene Coatings

    Science.gov (United States)

    Jia, Zhengmei; Huang, Jing; Gong, Yongfeng; Jin, Peipeng; Suo, Xinkun; Li, Hua

    2017-02-01

    High-density polyethylene (HDPE)-copper (Cu) composite coatings were prepared through depositing HDPE-Cu core-shell particles by flame spraying. The HDPE-Cu composite coatings and the HDPE coatings were aged in xenon lamp ageing testing chamber. The variations of chemical compositions and surface morphology of the coatings before and after the ageing testing were analyzed using infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and ultraviolet-visible spectrophotometer. Results show that there is no chemical composition variation in the HDPE-Cu coatings. Cracks were found on the surfaces of the HDPE coatings, while the HDPE-Cu coating shows almost intact surface morphology. These results suggest that the HDPE-Cu coatings present better anti-ageing performances than the HDPE coatings. Further assessment of the function of Cu shells on the anti-ageing property reveals that Cu shells not only enhanced the absorption of the coatings to ultraviolet, but also increased their reflectivity to visible light. Additionally, the Cu shells enhanced the decomposition temperature and thermal stability of HDPE in the composite coatings. These results give bright insight into potential anti-ageing applications of the polymer-based structures.

  10. High-precision abundances of Sc, Mn, Cu, and Ba in solar twins. Trends of element ratios with stellar age

    CERN Document Server

    Nissen, P E

    2016-01-01

    A previous study of correlations between element abundance ratios, [X/Fe], and ages of solar twin stars is extended to include Sc, Mn, Cu, and Ba. HARPS spectra with S/N > 600 are used to derive very precise (+/- 0.01 dex) differential abundances, and stellar ages with internal errors less than 1 Gyr are obtained by interpolation in the logg - Teff diagram between isochrones calculated with the Aarhus Stellar Evolution Code. For stars younger than 6 Gyr, [X/Fe] is tightly correlated with stellar age for all elements. For ages between 6 and 9 Gyr, the [X/Fe] - age correlations break down and the stars split up into two groups having respectively high and low [X/Fe] for the odd-Z elements. It is concluded that while stars in the solar neighborhood younger than about 6 Gyr were formed from interstellar gas with a smooth chemical evolution, older stars have originated from regions enriched by supernovae with different neutron excesses. Furthermore, the correlations between abundance ratios and stellar age suggest...

  11. Forensic age prediction for dead or living samples by use of methylation-sensitive high resolution melting.

    Science.gov (United States)

    Hamano, Yuya; Manabe, Sho; Morimoto, Chie; Fujimoto, Shuntaro; Ozeki, Munetaka; Tamaki, Keiji

    2016-07-01

    Age prediction with epigenetic information is now edging closer to practical use in forensic community. Many age-related CpG (AR-CpG) sites have proven useful in predicting age in pyrosequencing or DNA chip analyses. In this study, a wide range methylation status in the ELOVL2 and FHL2 promoter regions were detected with methylation-sensitive high resolution melting (MS-HRM) in a labor-, time-, and cost-effective manner. Non-linear-distributions of methylation status and chronological age were newly fitted to the logistic curve. Notably, these distributions were revealed to be similar in 22 living blood samples and 52 dead blood samples. Therefore, the difference of methylation status between living and dead samples suggested to be ignorable by MS-HRM. Additionally, the information from ELOVL2 and FHL2 were integrated into a logistic curve fitting model to develop a final predictive model through the multivariate linear regression of logit-linked methylation rates and chronological age with adjusted R(2)=0.83. Mean absolute deviation (MAD) was 7.44 for 74 training set and 7.71 for 30 additional independent test set, indicating that the final predicting model is accurate. This suggests that our MS-HRM-based method has great potential in predicting actual forensic age.

  12. Subcortical White Matter Changes with Normal Aging Detected by Multi-Shot High Resolution Diffusion Tensor Imaging.

    Science.gov (United States)

    Xie, Sheng; Zhang, Zhe; Chang, Feiyan; Wang, Yishi; Zhang, Zhenxia; Zhou, Zhenyu; Guo, Hua

    2016-01-01

    Subcortical white matter builds neural connections between cortical and subcortical regions and constitutes the basis of neural networks. It plays a very important role in normal brain function. Various studies have shown that white matter deteriorates with aging. However, due to the limited spatial resolution provided by traditional diffusion imaging techniques, microstructural information from subcortical white matter with normal aging has not been comprehensively assessed. This study aims to investigate the deterioration effect with aging in the subcortical white matter and provide a baseline standard for pathological disorder diagnosis. We apply our newly developed multi-shot high resolution diffusion tensor imaging, using self-feeding multiplexed sensitivity-encoding, to measure subcortical white matter changes in regions of interest of healthy persons with a wide age range. Results show significant fractional anisotropy decline and radial diffusivity increasing with age, especially in the anterior part of the brain. We also find that subcortical white matter has more prominent changes than white matter close to the central brain. The observed changes in the subcortical white matter may be indicative of a mild demyelination and a loss of myelinated axons, which may contribute to normal age-related functional decline.

  13. Subcortical White Matter Changes with Normal Aging Detected by Multi-Shot High Resolution Diffusion Tensor Imaging.

    Directory of Open Access Journals (Sweden)

    Sheng Xie

    Full Text Available Subcortical white matter builds neural connections between cortical and subcortical regions and constitutes the basis of neural networks. It plays a very important role in normal brain function. Various studies have shown that white matter deteriorates with aging. However, due to the limited spatial resolution provided by traditional diffusion imaging techniques, microstructural information from subcortical white matter with normal aging has not been comprehensively assessed. This study aims to investigate the deterioration effect with aging in the subcortical white matter and provide a baseline standard for pathological disorder diagnosis. We apply our newly developed multi-shot high resolution diffusion tensor imaging, using self-feeding multiplexed sensitivity-encoding, to measure subcortical white matter changes in regions of interest of healthy persons with a wide age range. Results show significant fractional anisotropy decline and radial diffusivity increasing with age, especially in the anterior part of the brain. We also find that subcortical white matter has more prominent changes than white matter close to the central brain. The observed changes in the subcortical white matter may be indicative of a mild demyelination and a loss of myelinated axons, which may contribute to normal age-related functional decline.

  14. Prevalence of Neutralizing Antibodies to Japanese Encephalitis Virus among High-Risk Age Groups in South Korea, 2010

    Science.gov (United States)

    Ju, Young Ran; Han, Myung Guk; Lee, Won-Ja; Jeong, Young Eui

    2016-01-01

    After an extensive vaccination policy, Japanese encephalitis (JE) was nearly eliminated since the mid-1980s in South Korea. Vaccination in children shifted the affected age of JE patients from children to adults. However, an abrupt increase in JE cases occurred in 2010, and this trend has continued. The present study aimed to investigate the prevalence of neutralizing antibodies to the JE virus (JEV) among high-risk age groups (≥40 years) in South Korea. A plaque reduction neutralization test was conducted to evaluate the prevalence of neutralizing antibodies to JEV in 945 subjects within four age groups (30–39, 40–49, 50–59, and 60–69 years) in 10 provinces. Of the 945 enrolled subjects, 927 (98.1%) exhibited antibodies against JEV. No significant differences were found in the prevalence of neutralizing antibodies according to sex, age, or occupation. However, there were significant differences in the plaque reduction rate according to age and occupation; oldest age group had a higher reduction rate, and subjects who were employed in agriculture or forestry also had a higher value than the other occupations. We also found that three provinces (Gangwon, Jeonnam, and Gyeongnam) had a relatively lower plaque reduction rate than the other locations. In addition, enzyme-linked immunosorbent assays were conducted to determine recent viral infections and 12 (2.2%) subjects were found to have been recently infected by the virus. In conclusion, the present study clearly indicated that the prevalence of neutralizing antibodies has been maintained at very high levels among adult age groups owing to vaccination or natural infections, or both. In the future, serosurveillance should be conducted periodically using more representative samples to better understand the population-level immunity to JE in South Korea. PMID:26807709

  15. Quadrivalent HPV vaccine effectiveness against high-grade cervical lesions by age at vaccination: A population-based study.

    Science.gov (United States)

    Herweijer, Eva; Sundström, Karin; Ploner, Alexander; Uhnoo, Ingrid; Sparén, Pär; Arnheim-Dahlström, Lisen

    2016-06-15

    Human papillomavirus (HPV) types 16/18, included in HPV vaccines, contribute to the majority of cervical cancer, and a substantial proportion of cervical intraepithelial neoplasia (CIN) grades 2/3 or worse (CIN2+/CIN3+) including adenocarcinoma in situ or worse. The aim of this study was to quantify the effect of quadrivalent HPV (qHPV) vaccination on incidence of CIN2+ and CIN3+. A nationwide cohort of girls and young women resident in Sweden 2006-2013 and aged 13-29 (n = 1,333,691) was followed for vaccination and histologically confirmed high-grade cervical lesions. Data were collected using the Swedish nationwide healthcare registers. Poisson regression was used to calculate incidence rate ratios (IRRs) and vaccine effectiveness [(1-IRR)x100%] comparing fully vaccinated with unvaccinated individuals. IRRs were adjusted for attained age and parental education, and stratified on vaccination initiation age. Effectiveness against CIN2+ was 75% (IRR = 0.25, 95%CI = 0.18-0.35) for those initiating vaccination before age 17, and 46% (IRR = 0.54, 95%CI = 0.46-0.64) and 22% (IRR = 0.78, 95%CI = 0.65-0.93) for those initiating vaccination at ages 17-19, and at ages 20-29, respectively. Vaccine effectiveness against CIN3+ was similar to vaccine effectiveness against CIN2+. Results were robust for both women participating to the organized screening program and for women at prescreening ages. We show high effectiveness of qHPV vaccination on CIN2+ and CIN3+ lesions, with greater effectiveness observed in girls younger at vaccination initiation. Continued monitoring of impact of HPV vaccination in the population is needed in order to evaluate both long-term vaccine effectiveness and to evaluate whether the vaccination program achieves anticipated effects in prevention of invasive cervical cancer.

  16. Averaged Lema\\^itre-Tolman-Bondi dynamics

    CERN Document Server

    Isidro, Eddy G Chirinos; Piattella, Oliver F; Zimdahl, Winfried

    2016-01-01

    We consider cosmological backreaction effects in Buchert's averaging formalism on the basis of an explicit solution of the Lema\\^itre-Tolman-Bondi (LTB) dynamics which is linear in the LTB curvature parameter and has an inhomogeneous bang time. The volume Hubble rate is found in terms of the volume scale factor which represents a derivation of the simplest phenomenological solution of Buchert's equations in which the fractional densities corresponding to average curvature and kinematic backreaction are explicitly determined by the parameters of the underlying LTB solution at the boundary of the averaging volume. This configuration represents an exactly solvable toy model but it does not adequately describe our "real" Universe.

  17. Average-passage flow model development

    Science.gov (United States)

    Adamczyk, John J.; Celestina, Mark L.; Beach, Tim A.; Kirtley, Kevin; Barnett, Mark

    1989-01-01

    A 3-D model was developed for simulating multistage turbomachinery flows using supercomputers. This average passage flow model described the time averaged flow field within a typical passage of a bladed wheel within a multistage configuration. To date, a number of inviscid simulations were executed to assess the resolution capabilities of the model. Recently, the viscous terms associated with the average passage model were incorporated into the inviscid computer code along with an algebraic turbulence model. A simulation of a stage-and-one-half, low speed turbine was executed. The results of this simulation, including a comparison with experimental data, is discussed.

  18. FREQUENTIST MODEL AVERAGING ESTIMATION: A REVIEW

    Institute of Scientific and Technical Information of China (English)

    Haiying WANG; Xinyu ZHANG; Guohua ZOU

    2009-01-01

    In applications, the traditional estimation procedure generally begins with model selection.Once a specific model is selected, subsequent estimation is conducted under the selected model without consideration of the uncertainty from the selection process. This often leads to the underreporting of variability and too optimistic confidence sets. Model averaging estimation is an alternative to this procedure, which incorporates model uncertainty into the estimation process. In recent years, there has been a rising interest in model averaging from the frequentist perspective, and some important progresses have been made. In this paper, the theory and methods on frequentist model averaging estimation are surveyed. Some future research topics are also discussed.

  19. Averaging of Backscatter Intensities in Compounds

    Science.gov (United States)

    Donovan, John J.; Pingitore, Nicholas E.; Westphal, Andrew J.

    2002-01-01

    Low uncertainty measurements on pure element stable isotope pairs demonstrate that mass has no influence on the backscattering of electrons at typical electron microprobe energies. The traditional prediction of average backscatter intensities in compounds using elemental mass fractions is improperly grounded in mass and thus has no physical basis. We propose an alternative model to mass fraction averaging, based of the number of electrons or protons, termed “electron fraction,” which predicts backscatter yield better than mass fraction averaging. PMID:27446752

  20. Experimental Demonstration of Squeezed State Quantum Averaging

    CERN Document Server

    Lassen, Mikael; Sabuncu, Metin; Filip, Radim; Andersen, Ulrik L

    2010-01-01

    We propose and experimentally demonstrate a universal quantum averaging process implementing the harmonic mean of quadrature variances. The harmonic mean protocol can be used to efficiently stabilize a set of fragile squeezed light sources with statistically fluctuating noise levels. The averaged variances are prepared probabilistically by means of linear optical interference and measurement induced conditioning. We verify that the implemented harmonic mean outperforms the standard arithmetic mean strategy. The effect of quantum averaging is experimentally tested both for uncorrelated and partially correlated noise sources with sub-Poissonian shot noise or super-Poissonian shot noise characteristics.

  1. The Average Lower Connectivity of Graphs

    Directory of Open Access Journals (Sweden)

    Ersin Aslan

    2014-01-01

    Full Text Available For a vertex v of a graph G, the lower connectivity, denoted by sv(G, is the smallest number of vertices that contains v and those vertices whose deletion from G produces a disconnected or a trivial graph. The average lower connectivity denoted by κav(G is the value (∑v∈VGsvG/VG. It is shown that this parameter can be used to measure the vulnerability of networks. This paper contains results on bounds for the average lower connectivity and obtains the average lower connectivity of some graphs.

  2. Cosmic inhomogeneities and averaged cosmological dynamics.

    Science.gov (United States)

    Paranjape, Aseem; Singh, T P

    2008-10-31

    If general relativity (GR) describes the expansion of the Universe, the observed cosmic acceleration implies the existence of a "dark energy." However, while the Universe is on average homogeneous on large scales, it is inhomogeneous on smaller scales. While GR governs the dynamics of the inhomogeneous Universe, the averaged homogeneous Universe obeys modified Einstein equations. Can such modifications alone explain the acceleration? For a simple generic model with realistic initial conditions, we show the answer to be "no." Averaging effects negligibly influence the cosmological dynamics.

  3. Changing mortality and average cohort life expectancy

    DEFF Research Database (Denmark)

    Schoen, Robert; Canudas-Romo, Vladimir

    2005-01-01

    of survivorship. An alternative aggregate measure of period mortality which has been seen as less sensitive to period changes, the cross-sectional average length of life (CAL) has been proposed as an alternative, but has received only limited empirical or analytical examination. Here, we introduce a new measure......, the average cohort life expectancy (ACLE), to provide a precise measure of the average length of life of cohorts alive at a given time. To compare the performance of ACLE with CAL and with period and cohort life expectancy, we first use population models with changing mortality. Then the four aggregate...

  4. Perceptual learning in Williams syndrome: looking beyond averages.

    Directory of Open Access Journals (Sweden)

    Patricia Gervan

    Full Text Available Williams Syndrome is a genetically determined neurodevelopmental disorder characterized by an uneven cognitive profile and surprisingly large neurobehavioral differences among individuals. Previous studies have already shown different forms of memory deficiencies and learning difficulties in WS. Here we studied the capacity of WS subjects to improve their performance in a basic visual task. We employed a contour integration paradigm that addresses occipital visual function, and analyzed the initial (i.e. baseline and after-learning performance of WS individuals. Instead of pooling the very inhomogeneous results of WS subjects together, we evaluated individual performance by expressing it in terms of the deviation from the average performance of the group of typically developing subjects of similar age. This approach helped us to reveal information about the possible origins of poor performance of WS subjects in contour integration. Although the majority of WS individuals showed both reduced baseline and reduced learning performance, individual analysis also revealed a dissociation between baseline and learning capacity in several WS subjects. In spite of impaired initial contour integration performance, some WS individuals presented learning capacity comparable to learning in the typically developing population, and vice versa, poor learning was also observed in subjects with high initial performance levels. These data indicate a dissociation between factors determining initial performance and perceptual learning.

  5. Aging Assessment of an Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR) Service Cable.

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Robert; Celina, Mathias Christopher; Redline, Erica Marie; White, II, Gregory Von

    2014-07-01

    Nuclear energy is one industry where aging of safety-related materials and components is of great concern. Many U.S. nuclear power plants are approaching, or have already exceeded, 40 years of age. Analysis comparing the cost of new plant construction versus long-term operation under extended plant licensing through 60 years strongly favors the latter option. To ensure the safe, reliable, and cost-effective long-term operation of nuclear power plants, many systems, structures, and components must be evaluated. Furthermore, as new analytical techniques and testing approaches are developed, it is imperative that we also validate, and if necessary, improve upon the previously employed Institute of Electrical and Electronic Engineers (IEEE) qualification standards originally written in 1974. Fortunately, this daunting task has global support, particularly in light of the new social and political climate surrounding nuclear energy in a post-Fukushima era.

  6. High age-adjusted prevalence of Parkinson's disease among Inuits in Greenland

    DEFF Research Database (Denmark)

    Wermuth, Lene; Pakkenberg, Henning; Jeune, Bernard

    2002-01-01

    The prevalence of PD among Inuits in Greenland has not been determined. The authors found 40 patients with PD at the prevalence date January 1, 2000. The crude prevalence of PD was estimated to be 81.0 per 100.000 inhabitants born in Greenland. However, owing to the low proportion of 50+ year old...... Inuits (16.5 vs 33.5% in Denmark) the age-adjusted prevalence was much higher-187.5 per 100,000 persons....

  7. Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations

    OpenAIRE

    Zhang, Fei; Inokoshi, Masanao; Batuk, Maria; Hadermann, Joke; Naert, Ignace; Van Meerbeek, Bart; Vleugels, Jef

    2016-01-01

    Abstract: Objective. The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. Methods. Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning elect...

  8. Effect of aging and oxidation on strain hardening behaviour of a nickel-free high nitrogen austenitic stainless steel

    Science.gov (United States)

    Karthik, B.; Veerababu, R.; Satyanarayana, D. V. V.

    2016-05-01

    Effect of aging and oxidation on strain hardening behaviour of a nickel-free high nitrogen austenitic stainless steel has been investigated using room temperature tensile tests and TEM. The alloy in both oxidised and unoxidised conditions exhibits a transition in flow behaviour that can be described best by the Ludwigson flow relationship as evident from the lowest values of the sum of residual squares, χ 2, of the fit. The transition in macroscopic flow behaviour with strain has been correlated to change in deformation mechanism from planar slip in the low strain regime (LSR) to deformation twinning and slip in the high strain regime (HSR) in solution treated (ST) condition of the alloy. However, the LSR of the alloy aged for longer times (>100 h) is characterized by the formation of dislocation tangles, while the HSR is marked by the formation of well-defined finer dislocation cell structure. This difference in deformation sub-structures in low and high strain regimes between ST and long term aged samples has been correlated to the change in stacking fault energy due to the precipitation of Cr2N and σ-phases. Further, the alloy in ST condition exhibits the highest strain hardening rate, which then progressively decreases with aging time.

  9. Test of a device for accelerated ageing of polymeric material in high concentrated sunlight at the DLR solar furnace

    Energy Technology Data Exchange (ETDEWEB)

    Witzke, A.; Neumann, A.; Kaluza, J. [German Aerospace Center (DLR), Solar Energy Technology, Cologne (Germany); Demuth, M.; Ritterskamp, P. [Max-Planck-Inst. fuer Strahlenchemie, Muelheim a.d.R. (Germany)

    2001-07-01

    Within this study the design and first tests of a device for accelerated ageing with high concentrated sunlight have been described. Firstly, the device was designed for testing samples of lacquer for the car industry. It is based on two points: first, the photochemical effect that the ageing of polymers is mainly initiated by the UV solar radiation and, second, on the idea to accelerate the ageing process by increasing the UV radiation dose. Therefore the concentrated sunlight at the DLR Solar Furnace is filtered by a cold-mirror that reflects the radiation with a wavelength below 450 nm onto the samples. The samples are fixed in a chamber where they can simultaneously be wetted by a spraying device. The first tests show that this device enables us to radiate the relevant samples with a high UV radiation intensity without overheating them. During one day irradiation at the DLR Solar Furnace in March 2001 we reach an UV radiation dose which is about sixteen times higher than the dose after 24 hours irradiation in common used weathering devices. Further tests at the DLR Solar Furnace have to examine in what way this increased radiation dose leads to a high accelerated ageing of the polymeric material. (orig.)

  10. High resolution isotopic ages for the early Miocene "Patagoniense" transgression in Southwest Patagonia: Stratigraphic implications

    Science.gov (United States)

    Cuitiño, José I.; Pimentel, Marcio M.; Ventura Santos, Roberto; Scasso, Roberto A.

    2012-10-01

    The classical marine Patagoniense succession at Lago Argentino, southwestern Patagonia (Argentina), known as Estancia 25 de Mayo Formation, was dated by radiometric U-Pb on zircon grains from pyroclastic rocks and 87Sr/86Sr ratio on calcitic oyster shells. U-Pb data yielded an age of 19.14 Ma for the lower portion of the Patagoniense succession and 18.85 Ma for the lowermost part of the overlying Santa Cruz Formation. 87Sr/86Sr data yielded ages ranging from 20.05 Ma at the lower part and 19.1 Ma for the upper portion of the Estancia 25 de Mayo Formation, in good agreement with respect to the U-Pb results. Our results constrain the age of these beds entirely into the early Miocene Burdigalian stage, and locally into the Superpatagoniense stage. Correlation with other Patagoniense units in Santa Cruz, especially in the westernmost parts of the Austral Basin, reveals the existence of a shallow and extended sea, and lack of correlation with global sea-level highstands suggests a local Andean tectonic overprint as the cause of the sea level rise.

  11. Effect of high-intensity exercise on aged mouse brain mitochondria, neurogenesis, and inflammation.

    Science.gov (United States)

    E, Lezi; Burns, Jeffrey M; Swerdlow, Russell H

    2014-11-01

    In aged mice, we assessed how intensive exercise affects brain bioenergetics, inflammation, and neurogenesis-relevant parameters. After 8 weeks of a supra-lactate threshold treadmill exercise intervention, 21-month-old C57BL/6 mice showed increased brain peroxisome proliferator-activated receptor gamma coactivator-1α protein, mammalian target of rapamycin and phospho-mammalian target of rapamycin protein, citrate synthase messenger RNA, and mitochondrial DNA copy number. Hippocampal vascular endothelial growth factor A (VEGF-A) gene expression trended higher, and a positive correlation between VEGF-A and PRC messenger RNA levels was observed. Brain doublecortin, brain-derived neurotrophic factor, tumor necrosis factor-α, and CCL11 gene expression, as well as plasma CCL11 protein levels, were unchanged. Despite these apparent negative findings, a negative correlation between plasma CCL11 protein levels and hippocampal doublecortin gene expression was observed; further analysis indicated exercise may mitigate this relationship. Overall, our data suggest supra-lactate threshold exercise activates a partial mitochondrial biogenesis in aged mice, and a gene (VEGF-A) known to support neurogenesis. Our data are consistent with another study that found systemic inflammation in general, and CCL11 protein specifically, suppresses hippocampal neurogenesis. Our study supports the view that intense exercise above the lactate threshold may benefit the aging brain; future studies to address the extent to which exercise-generated lactate mediates the observed effects are warranted.

  12. Tuberculosis in ageing: high rates, complex diagnosis and poor clinical outcomes

    Science.gov (United States)

    Cruz-Hervert, Luis Pablo; García-García, Lourdes; Ferreyra-Reyes, Leticia; Bobadilla-del-Valle, Miriam; Cano-Arellano, Bulmaro; Canizales-Quintero, Sergio; Ferreira-Guerrero, Elizabeth; Báez-Saldaña, Renata; Téllez-Vázquez, Norma; Nava-Mercado, Ariadna; Juárez-Sandino, Luis; Delgado-Sánchez, Guadalupe; Fuentes-Leyra, César Alejandro; Montero-Campos, Rogelio; Martínez-Gamboa, Rosa Areli; Small, Peter M.; Sifuentes-Osornio, José; Ponce-de-León, Alfredo

    2012-01-01

    Background: worldwide, the frequency of tuberculosis among older people almost triples that observed among young adults. Objective: to describe clinical and epidemiological consequences of pulmonary tuberculosis among older people. Methods: we screened persons with a cough lasting more than 2 weeks in Southern Mexico from March 1995 to February 2007. We collected clinical and mycobacteriological information (isolation, identification, drug-susceptibility testing and IS6110-based genotyping and spoligotyping) from individuals with bacteriologically confirmed pulmonary tuberculosis. Patients were treated in accordance with official norms and followed to ascertain treatment outcomes, retreatment, and vital status. Results: eight hundred ninety-three tuberculosis patients were older than 15 years of age; of these, 147 (16.5%) were 65 years of age or older. Individuals ≥65 years had significantly higher rates of recently transmitted and reactivated tuberculosis. Older age was associated with treatment failure (OR = 5.37; 95% CI: 1.06–27.23; P = 0.042), and death due to tuberculosis (HR = 3.52; 95% CI: 1.78–6.96; P < 0.001) adjusting for sociodemographic and clinical variables. Conclusions: community-dwelling older individuals participate in chains of transmission indicating that tuberculosis is not solely due to the reactivation of latent disease. Untimely and difficult diagnosis and a higher risk of poor outcomes even after treatment completion emphasise the need for specific strategies for this vulnerable group. PMID:22431155

  13. Sea Surface Temperature Average_SST_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sea surface temperature collected via satellite imagery from http://www.esrl.noaa.gov/psd/data/gridded/data.noaa.ersst.html and averaged for each region using ArcGIS...

  14. Appeals Council Requests - Average Processing Time

    Data.gov (United States)

    Social Security Administration — This dataset provides annual data from 1989 through 2015 for the average processing time (elapsed time in days) for dispositions by the Appeals Council (AC) (both...

  15. Average Vegetation Growth 1990 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1990 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  16. Average Vegetation Growth 1997 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1997 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  17. Average Vegetation Growth 1992 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1992 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  18. Average Vegetation Growth 2001 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 2001 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  19. Average Vegetation Growth 1995 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1995 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  20. Average Vegetation Growth 2000 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 2000 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  1. Average Vegetation Growth 1998 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1998 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  2. Average Vegetation Growth 1994 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1994 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  3. MN Temperature Average (1961-1990) - Line

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data set depicts 30-year averages (1961-1990) of monthly and annual temperatures for Minnesota. Isolines and regions were created using kriging and...

  4. Average Vegetation Growth 1996 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1996 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  5. Average Vegetation Growth 2005 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 2005 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  6. Average Vegetation Growth 1993 - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer is a grid map of 1993 average vegetation growth for Alaska and the conterminous United States. The nominal spatial resolution is 1 kilometer and the...

  7. MN Temperature Average (1961-1990) - Polygon

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data set depicts 30-year averages (1961-1990) of monthly and annual temperatures for Minnesota. Isolines and regions were created using kriging and...

  8. Spacetime Average Density (SAD) Cosmological Measures

    CERN Document Server

    Page, Don N

    2014-01-01

    The measure problem of cosmology is how to obtain normalized probabilities of observations from the quantum state of the universe. This is particularly a problem when eternal inflation leads to a universe of unbounded size so that there are apparently infinitely many realizations or occurrences of observations of each of many different kinds or types, making the ratios ambiguous. There is also the danger of domination by Boltzmann Brains. Here two new Spacetime Average Density (SAD) measures are proposed, Maximal Average Density (MAD) and Biased Average Density (BAD), for getting a finite number of observation occurrences by using properties of the Spacetime Average Density (SAD) of observation occurrences to restrict to finite regions of spacetimes that have a preferred beginning or bounce hypersurface. These measures avoid Boltzmann brain domination and appear to give results consistent with other observations that are problematic for other widely used measures, such as the observation of a positive cosmolo...

  9. A practical guide to averaging functions

    CERN Document Server

    Beliakov, Gleb; Calvo Sánchez, Tomasa

    2016-01-01

    This book offers an easy-to-use and practice-oriented reference guide to mathematical averages. It presents different ways of aggregating input values given on a numerical scale, and of choosing and/or constructing aggregating functions for specific applications. Building on a previous monograph by Beliakov et al. published by Springer in 2007, it outlines new aggregation methods developed in the interim, with a special focus on the topic of averaging aggregation functions. It examines recent advances in the field, such as aggregation on lattices, penalty-based aggregation and weakly monotone averaging, and extends many of the already existing methods, such as: ordered weighted averaging (OWA), fuzzy integrals and mixture functions. A substantial mathematical background is not called for, as all the relevant mathematical notions are explained here and reported on together with a wealth of graphical illustrations of distinct families of aggregation functions. The authors mainly focus on practical applications ...

  10. Rotational averaging of multiphoton absorption cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Friese, Daniel H., E-mail: daniel.h.friese@uit.no; Beerepoot, Maarten T. P.; Ruud, Kenneth [Centre for Theoretical and Computational Chemistry, University of Tromsø — The Arctic University of Norway, N-9037 Tromsø (Norway)

    2014-11-28

    Rotational averaging of tensors is a crucial step in the calculation of molecular properties in isotropic media. We present a scheme for the rotational averaging of multiphoton absorption cross sections. We extend existing literature on rotational averaging to even-rank tensors of arbitrary order and derive equations that require only the number of photons as input. In particular, we derive the first explicit expressions for the rotational average of five-, six-, and seven-photon absorption cross sections. This work is one of the required steps in making the calculation of these higher-order absorption properties possible. The results can be applied to any even-rank tensor provided linearly polarized light is used.

  11. Rotational averaging of multiphoton absorption cross sections

    Science.gov (United States)

    Friese, Daniel H.; Beerepoot, Maarten T. P.; Ruud, Kenneth

    2014-11-01

    Rotational averaging of tensors is a crucial step in the calculation of molecular properties in isotropic media. We present a scheme for the rotational averaging of multiphoton absorption cross sections. We extend existing literature on rotational averaging to even-rank tensors of arbitrary order and derive equations that require only the number of photons as input. In particular, we derive the first explicit expressions for the rotational average of five-, six-, and seven-photon absorption cross sections. This work is one of the required steps in making the calculation of these higher-order absorption properties possible. The results can be applied to any even-rank tensor provided linearly polarized light is used.

  12. Monthly snow/ice averages (ISCCP)

    Data.gov (United States)

    National Aeronautics and Space Administration — September Arctic sea ice is now declining at a rate of 11.5 percent per decade, relative to the 1979 to 2000 average. Data from NASA show that the land ice sheets in...

  13. Average Annual Precipitation (PRISM model) 1961 - 1990

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer shows polygons of average annual precipitation in the contiguous United States, for the climatological period 1961-1990. Parameter-elevation...

  14. Occupational noise, smoking, and a high body mass index are risk factors for age-related hearing impairment and moderate alcohol consumption is protective: A European population-based multicenter study

    DEFF Research Database (Denmark)

    Fransen, E.; Topsakal, V.; Hendrickx, J.J.

    2008-01-01

    exposure was associated with a significant loss of hearing at high sound frequencies (> 1 kHz). Smoking significantly increased high-frequency hearing loss, and the effect was dose-dependent. The effect of smoking remained significant when accounting for cardiovascular disease events. Taller people had......-tone average [PTA]) were collected and the participants filled out a questionnaire on environmental risk factors and medical history. People with a history of disease that could affect hearing were excluded. PTAs were adjusted for age and sex and tested for association with exposure to risk factors. Noise...

  15. On the relativistic mass function and averaging in cosmology

    CERN Document Server

    Ostrowski, Jan J; Roukema, Boudewijn F

    2016-01-01

    The general relativistic description of cosmological structure formation is an important challenge from both the theoretical and the numerical point of views. In this paper we present a brief prescription for a general relativistic treatment of structure formation and a resulting mass function on galaxy cluster scales in a highly generic scenario. To obtain this we use an exact scalar averaging scheme together with the relativistic generalization of Zel'dovich's approximation (RZA) that serves as a closure condition for the averaged equations.

  16. Woodland: dynamics of average diameters of coniferous tree stands of the principal forest types

    Directory of Open Access Journals (Sweden)

    R. A. Ziganshin

    2016-08-01

    Full Text Available The analysis of age dynamics of average diameters of deciduous tree stands of different forest types at Highland Khamar-Daban (natural woodland in South-East Baikal Lake region has been done. The aggregate data of average tree, the analysis of age dynamics of average diameters of a deciduous tree stands of stand diameters by age classes, as well as tree stand current periodic and overall average increment are presented and discussed in the paper. Forest management appraisal is done. The most representative forest types have been selected to be analyzed. There were nine of them including three Siberian stone pine Pinus sibirica Du Tour stands, three Siberian fir Abies sibirica Ledeb. stands, one Siberian spruce Picea obovata Ledeb. stand, and two dwarf Siberian pine Pinus pumila (Pallas Regel stands. The whole high-altitude range of mountain taiga has been evaluated. Mathematical and statistic indicators have been calculated for every forest type. Stone pine stands are the largest. Dynamics of mean diameters of forest stands have been examined by dominant species for every forest type. Quite a number of interesting facts have been elicited. Generally, all species have maximal values of periodic annual increment that is typical for young stands, but further decrease of increment is going on differently and connects to the different lifetime of wood species. It is curious that annual increment of the dwarf Siberian pine stands almost does not decrease with aging. As for mean annual increment, it is more stable than periodic annual increment. From the fifth age class (age of stand approaching maturity mean annual increment of cedar stands varies from 0.20 to 0.24 cm per year; from 0.12–0.15 to 0.18–0.21 cm per year – in fir stands; from 0.18 to 0.24 cm per year – in spruce stands; and from 0.02–0.03 to 0.05–0.06 cm per year – in draft pine stands. Mean annual increment of dwarf Siberian pine increases with aging and increment of other

  17. Symmetric Euler orientation representations for orientational averaging.

    Science.gov (United States)

    Mayerhöfer, Thomas G

    2005-09-01

    A new kind of orientation representation called symmetric Euler orientation representation (SEOR) is presented. It is based on a combination of the conventional Euler orientation representations (Euler angles) and Hamilton's quaternions. The properties of the SEORs concerning orientational averaging are explored and compared to those of averaging schemes that are based on conventional Euler orientation representations. To that aim, the reflectance of a hypothetical polycrystalline material with orthorhombic crystal symmetry was calculated. The calculation was carried out according to the average refractive index theory (ARIT [T.G. Mayerhöfer, Appl. Spectrosc. 56 (2002) 1194]). It is shown that the use of averaging schemes based on conventional Euler orientation representations leads to a dependence of the result from the specific Euler orientation representation that was utilized and from the initial position of the crystal. The latter problem can be overcome partly by the introduction of a weighing factor, but only for two-axes-type Euler orientation representations. In case of a numerical evaluation of the average, a residual difference remains also if a two-axes type Euler orientation representation is used despite of the utilization of a weighing factor. In contrast, this problem does not occur if a symmetric Euler orientation representation is used as a matter of principle, while the result of the averaging for both types of orientation representations converges with increasing number of orientations considered in the numerical evaluation. Additionally, the use of a weighing factor and/or non-equally spaced steps in the numerical evaluation of the average is not necessary. The symmetrical Euler orientation representations are therefore ideally suited for the use in orientational averaging procedures.

  18. Cosmic Inhomogeneities and the Average Cosmological Dynamics

    OpenAIRE

    Paranjape, Aseem; Singh, T. P.

    2008-01-01

    If general relativity (GR) describes the expansion of the Universe, the observed cosmic acceleration implies the existence of a `dark energy'. However, while the Universe is on average homogeneous on large scales, it is inhomogeneous on smaller scales. While GR governs the dynamics of the \\emph{in}homogeneous Universe, the averaged \\emph{homogeneous} Universe obeys modified Einstein equations. Can such modifications alone explain the acceleration? For a simple generic model with realistic ini...

  19. Average Bandwidth Allocation Model of WFQ

    Directory of Open Access Journals (Sweden)

    Tomáš Balogh

    2012-01-01

    Full Text Available We present a new iterative method for the calculation of average bandwidth assignment to traffic flows using a WFQ scheduler in IP based NGN networks. The bandwidth assignment calculation is based on the link speed, assigned weights, arrival rate, and average packet length or input rate of the traffic flows. We prove the model outcome with examples and simulation results using NS2 simulator.

  20. Prevalence of cryptosporidium in children under 5 years of age, immunocompromised patients and high risk persons in Isfahan province

    Directory of Open Access Journals (Sweden)

    Mehdi Azami

    2008-09-01

    Full Text Available Background: Cryptosporidium is an important enteric parasite which causes diarrheal illness in humans and animals worldwide. With attention to the role of cryptosporidium in producing diarrhea and mortality in immunocopromised patients and children under 5 years of age, the present study was designed to identify the prevalence of cryptosporidium and potential risk factors in Isfahan province. Methods: This descriptive study was done in Isfahan province from October 2003 to April 2004. A total of 642 children under 5 years of age, immunocompromised patients and high risk persons selected randomly and their stool samples were studied microscopically using Sheater's Sucrose Flotation technique and stained by modified Ziehl-Neelsen staining method. Results: The overall prevalence of cryptosporidium was 4.7% (30 samples. The prevalence rates of infection were 4.6%, 3.5% and 5.4% in children under 5 years of age, immunocompromised patients and high risk persons, respectively. The highest prevalence of infection (6.2% belonged to 1-2 years old children in the group of under 5 years of age, 3-4 years in immunocompromised patients group and 5-10 years in high risk persons group (10%, 6.2% and 14.8% respectively. Conclusion: Cryptosporidium is significantly prevalent in children under 5 years of age, immune compromised patients and high risk persons in Isfahan province. Therefore, health policy makers have to design a plan to identify and treat infected subjected with cryptosporidium thus as a result the transmission of the disease can be prevented in the society.