WorldWideScience

Sample records for surveyor mgs observations

  1. The MGS Avionics System Architecture: Exploring the Limits of Inheritance

    Science.gov (United States)

    Bunker, R.

    1994-01-01

    Mars Global Surveyor (MGS) avionics system architecture comprises much of the electronics on board the spacecraft: electrical power, attitude and articulation control, command and data handling, telecommunications, and flight software. Schedule and cost constraints dictated a mix of new and inherited designs, especially hardware upgrades based on findings of the Mars Observer failure review boards.

  2. MARS GLOBAL SURVEYOR RAW DATA SET - CRUISE V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Global Surveyor (MGS) Radio Science (RS) Raw Data Archive (RDA) is a time-ordered collection of raw and partially processed data collected during the MGS...

  3. Energetic particles detected by the Electron Reflectometer instrument on the Mars Global Surveyor, 1999-2006

    DEFF Research Database (Denmark)

    Delory, Gregory T.; Luhmann, Janet G.; Brain, David

    2012-01-01

    events at Mars associated with solar flares and coronal mass ejections, which includes the identification of interplanetary shocks. MGS observations of energetic particles at varying geometries between the Earth and Mars that include shocks produced by halo, limb, and backsided events provide a unique......We report the observation of galactic cosmic rays and solar energetic particles by the Electron Reflectometer instrument aboard the Mars Global Surveyor (MGS) spacecraft from May of 1999 to the mission conclusion in November 2006. Originally designed to detect low-energy electrons, the Electron...... recorded high energy galactic cosmic rays with similar to 45% efficiency. Comparisons of this data to galactic cosmic ray proton fluxes obtained from the Advanced Composition Explorer yield agreement to within 10% and reveal the expected solar cycle modulation as well as shorter timescale variations. Solar...

  4. Mars Global Surveyor Data Analysis Program. Origins of Small Volcanic Cones: Eruption Mechanisms and Implications for Water on Mars

    Science.gov (United States)

    Fagents, Sarah A.; Greeley, Ronald; Thordarson, Thorvaldur

    2002-01-01

    The goal of the proposed work was to determine the origins of small volcanic cones observed in Mars Global Surveyor (MGS) data, and their implications for regolith ice stores and magma volatile contents. For this 1-year study, our approach involved a combination of: Quantitative morphologic analysis and interpretation of Mars Orbiter Camera (MOC) and Mars Orbiter Laser Altimeter (MOLA) data; Numerical modeling of eruption processes responsible for producing the observed features; Fieldwork on terrestrial analogs in Iceland. Following this approach, this study succeeded in furthering our understanding of (i) the spatial and temporal distribution of near-surface water ice, as defined by the distribution and sizes of rootless volcanic cones ("pseudocraters"), and (ii) the properties, eruption conditions, and volatile contents of magmas producing primary vent cones.

  5. Observational evidence for composite grains in an AGB outflow: MgS in the extreme carbon star LL Pegasi

    NARCIS (Netherlands)

    Lombaert, R.; de Vries, B.L.; de Koter, A.; Decin, L.; Min, M.; Smolders, K.; Mutschke, H.; Waters, L.B.F.M.

    2012-01-01

    The broad 30 μm feature in carbon stars is commonly attributed to MgS dust particles. However, reproducing the 30 μm feature with homogeneous MgS grains would require much more sulfur relative to the solar abundance. Direct gas-phase condensation of MgS occurs at a low efficiency. Precipitation of

  6. The Gravity Field of Mars From MGS, Mars Odyssey, and MRO Radio Science

    Science.gov (United States)

    Genova, Antonio; Goossens, Sander; Lemoine, Frank G.; Mazarico, Erwan; Smith, David E.; Zuber, Maria T.

    2015-01-01

    The Mars Global Surveyor (MGS), Mars Odyssey (ODY), and Mars Reconnaissance Orbiter (MRO) missions have enabled NASA to conduct reconnaissance and exploration of Mars from orbit for sixteen consecutive years. These radio systems on these spacecraft enabled radio science in orbit around Mars to improve the knowledge of the static structure of the Martian gravitational field. The continuity of the radio tracking data, which cover more than a solar cycle, also provides useful information to characterize the temporal variability of the gravity field, relevant to the planet's internal dynamics and the structure and dynamics of the atmosphere [1]. MGS operated for more than 7 years, between 1999 and 2006, in a frozen sun-synchronous, near-circular, polar orbit with the periapsis at approximately 370 km altitude. ODY and MRO have been orbiting Mars in two separate sun-synchronous orbits at different local times and altitudes. ODY began its mapping phase in 2002 with the periapis at approximately 390 km altitude and 4-5pm Local Solar Time (LST), whereas the MRO science mission started in November 2006 with the periapis at approximately 255 km altitude and 3pm LST. The 16 years of radio tracking data provide useful information on the atmospheric density in the Martian upper atmosphere. We used ODY and MRO radio data to recover the long-term periodicity of the major atmospheric constituents -- CO2, O, and He -- at the orbit altitudes of these two spacecraft [2]. The improved atmospheric model provides a better prediction of the annual and semi-annual variability of the dominant species. Therefore, the inclusion of the recovered model leads to improved orbit determination and an improved gravity field model of Mars with MGS, ODY, and MRO radio tracking data.

  7. Accelerated Adaptive MGS Phase Retrieval

    Science.gov (United States)

    Lam, Raymond K.; Ohara, Catherine M.; Green, Joseph J.; Bikkannavar, Siddarayappa A.; Basinger, Scott A.; Redding, David C.; Shi, Fang

    2011-01-01

    The Modified Gerchberg-Saxton (MGS) algorithm is an image-based wavefront-sensing method that can turn any science instrument focal plane into a wavefront sensor. MGS characterizes optical systems by estimating the wavefront errors in the exit pupil using only intensity images of a star or other point source of light. This innovative implementation of MGS significantly accelerates the MGS phase retrieval algorithm by using stream-processing hardware on conventional graphics cards. Stream processing is a relatively new, yet powerful, paradigm to allow parallel processing of certain applications that apply single instructions to multiple data (SIMD). These stream processors are designed specifically to support large-scale parallel computing on a single graphics chip. Computationally intensive algorithms, such as the Fast Fourier Transform (FFT), are particularly well suited for this computing environment. This high-speed version of MGS exploits commercially available hardware to accomplish the same objective in a fraction of the original time. The exploit involves performing matrix calculations in nVidia graphic cards. The graphical processor unit (GPU) is hardware that is specialized for computationally intensive, highly parallel computation. From the software perspective, a parallel programming model is used, called CUDA, to transparently scale multicore parallelism in hardware. This technology gives computationally intensive applications access to the processing power of the nVidia GPUs through a C/C++ programming interface. The AAMGS (Accelerated Adaptive MGS) software takes advantage of these advanced technologies, to accelerate the optical phase error characterization. With a single PC that contains four nVidia GTX-280 graphic cards, the new implementation can process four images simultaneously to produce a JWST (James Webb Space Telescope) wavefront measurement 60 times faster than the previous code.

  8. MGS Esmeralda: new large seed mungbean cultivar MGS Esmeralda: nova cultivar de mungo-verde de sementes grandes

    Directory of Open Access Journals (Sweden)

    Rogério Faria Vieira

    2008-06-01

    Full Text Available Mungbean cultivar MGS Esmeralda was developed by Asian Vegetable Research and Development Center (Shanhua, Taiwan, as a result of crossing between the lines VC 1973A and VC 2768A. In ten trials conducted in the State of Minas Gerais, Brazil, it produced 13.5% more grains than 'Ouro Verde MG-2' (control cultivar, and its highest yield was 2,550 kg ha-1. The cultivar MGS Esmeralda is more susceptible to lodging, and its pods mature more uniformly than Ouro Verde MG-2 pods. One hundred-seed mass of 'MGS Esmeralda' ranged between 5.5 and 6.8 g. Both cultivars are susceptible to powdery mildew and cercospora leaf spot.A cultivar de mungo-verde MGS Esmeralda foi criada pelo Asian Vegetable Research and Development Center, localizado em Shanhua, Formosa. Ela é resultado do cruzamento entre as linhagens VC 1973A e VC 2768A. Em dez ensaios conduzidos em Minas Gerais, ela produziu 13,5% mais grãos do que a cultivar Ouro Verde MG-2 (testemunha, e sua produtividade mais alta foi 2.550 kg ha-1. A cultivar MGS Esmeralda é mais suscetível ao acamamento do que a Ouro Verde MG-2, mas suas vagens amadurecem mais uniformemente. A massa de 100 grãos da 'MGS Esmeralda' varia de 5,5 a 6,8 g. Ambas as cultivares são suscetíveis ao oídio e à cercosporiose.

  9. MGS Radio Science Measurements of Atmospheric Dynamics on Mars

    Science.gov (United States)

    Hinson, D. P.

    2001-12-01

    The Sun-synchronous, polar orbit of Mars Global Surveyor (MGS) provides frequent opportunities for radio occultation sounding of the neutral atmosphere. The basic result of each experiment is a profile of pressure and temperature versus planetocentric radius and geopotential. More than 4000 profiles were obtained during the 687-day mapping phase of the mission, and additional observations are underway. These measurements allow detailed characterization of planetary-scale dynamics, including stationary planetary (or Rossby) waves and transient waves produced by instability. For example, both types of dynamics were observed near 67° S during midwinter of the southern hemisphere (Ls=134° --160° ). Planetary waves are the most prominent dynamical feature in this subset of data. At zonal wave number s=1, both the temperature and geopotential fields tilt westward with increasing height, as expected for vertically-propagating planetary waves forced at the surface. The wave-2 structure is more nearly barotropic. The amplitude in geopotential height at Ls=150° increases from ~200 m near the surface to ~700 m at 10 Pa. The corresponding meridional wind speed increases from ~5 m s-1 near the surface to ~20 m s-1 at 10 Pa. Traveling ``baroclinic'' waves also appear intermittently during this interval. The dominant mode has a period of ~2 sols, s=3, and a peak amplitude of ~7 K at 300 Pa. Stong zonal variations in eddy amplitude signal the presence of a possible ``storm zone'' at 150° --330° E longitude. This talk will include other examples of these phenomena as well as comparisons with computer simulations by a Martian general circulation model (MGCM).

  10. Mars Global Surveyor Ka-Band Frequency Data Analysis

    Science.gov (United States)

    Morabito, D.; Butman, S.; Shambayati, S.

    2000-01-01

    The Mars Global Surveyor (MGS) spacecraft, launched on November 7, 1996, carries an experimental space-to-ground telecommunications link at Ka-band (32 GHz) along with the primary X-band (8.4 GHz) downlink. The signals are simultaneously transmitted from a 1.5-in diameter parabolic high gain antenna (HGA) on MGS and received by a beam-waveguide (BWG) R&D 34-meter antenna located in NASA's Goldstone Deep Space Network (DSN) complex near Barstow, California. The projected 5-dB link advantage of Ka-band relative to X-band was confirmed in previous reports using measurements of MGS signal strength data acquired during the first two years of the link experiment from December 1996 to December 1998. Analysis of X-band and Ka-band frequency data and difference frequency (fx-fka)/3.8 data will be presented here. On board the spacecraft, a low-power sample of the X-band downlink from the transponder is upconverted to 32 GHz, the Ka-band frequency, amplified to I-W using a Solid State Power Amplifier, and radiated from the dual X/Ka HGA. The X-band signal is amplified by one of two 25 W TWTAs. An upconverter first downconverts the 8.42 GHz X-band signal to 8 GHz and then multiplies using a X4 multiplier producing the 32 GHz Ka-band frequency. The frequency source selection is performed by an RF switch which can be commanded to select a VCO (Voltage Controlled Oscillator) or USO (Ultra-Stable Oscillator) reference. The Ka-band frequency can be either coherent with the X-band downlink reference or a hybrid combination of the USO and VCO derived frequencies. The data in this study were chosen such that the Ka-band signal is purely coherent with the X-band signal, that is the downconverter is driven by the same frequency source as the X-band downlink). The ground station used to acquire the data is DSS-13, a 34-meter BWG antenna which incorporates a series of mirrors inside beam waveguide tubes which guide the energy to a subterranean pedestal room, providing a stable environment

  11. Solar wind modulation of the Martian ionosphere observed by Mars Global Surveyor

    Directory of Open Access Journals (Sweden)

    J.-S. Wang

    2004-06-01

    Full Text Available Electron density profiles in the Martian ionosphere observed by the radio occultation experiment on board Mars Global Surveyor have been analyzed to determine if the densities are influenced by the solar wind. Evidence is presented that the altitude of the maximum ionospheric electron density shows a positive correlation to the energetic proton flux in the solar wind. The solar wind modulation of the Martian ionosphere can be attributed to heating of the neutral atmosphere by the solar wind energetic proton precipitation. The modulation is observed to be most prominent at high solar zenith angles. It is argued that this is consistent with the proposed modulation mechanism.

  12. Results on a Questionnaire to Soil Surveyors Around the World ...

    African Journals Online (AJOL)

    Seventy respondents from 40 countries replied to a questionnaire on methodologies used in soil surveys. Observations and conclusions worth noting are given. Some terminologies in soil surveys are not conceived and used consistently by soil surveyors. The nature of soil surveys is determined by soil surveyors ...

  13. Constraints on the Within Season and Between Year Variability of the North Residual Cap from MGS-TES

    Science.gov (United States)

    Calvin, W. M.; Titus, T. N.; Mahoney, S. A.

    2003-01-01

    There is a long history of telescopic and spacecraft observations of the polar regions of Mars. The finely laminated ice deposits and surrounding layered terrains are commonly thought to contain a record of past climate conditions and change. Understanding the basic nature of the deposits and their mineral and ice constituents is a continued focus of current and future orbited missions. Unresolved issues in Martian polar science include a) the unusual nature of the CO2 ice deposits ("Swiss Cheese", "slab ice" etc.) b) the relationship of the ice deposits to underlying layered units (which differs from the north to the south), c) understanding the seasonal variations and their connections to the finely laminated units observed in high-resolution images and d) the relationship of dark materials in the wind-swept lanes and reentrant valleys to the surrounding dark dune and surface materials. Our work focuses on understanding these issues in relationship to the north residual ice cap. Recent work using Mars Global Surveyor (MGS) data sets have described evolution of the seasonal CO2 frost deposits. In addition, the north polar residual ice cap exhibits albedo variations between Mars years and within the summer season. The Thermal Emission Spectrometer (TES) data set can augment these observations providing additional constraints such as temperature evolution and spectral properties associated with ice and rocky materials. Exploration of these properties is the subject of our current study.

  14. Mars Global Surveyor Radio Science Electron Density Profiles: Interannual Variability and Implications for the Neutral Atmosphere

    Science.gov (United States)

    Bougher, S. W.; Engel, S.; Hinson, D. P.; Murphy, J. R.

    2003-01-01

    The Mars Global Surveyor (MGS) Radio Science (RS) experiment employs an ultrastable oscillator aboard the spacecraft. The signal from the oscillator to Earth is refracted by the Martian ionosphere, allowing retrieval of electron density profiles versus radius and geopotential. The present analysis is carried out on five sets of occultation measurements: (1) four obtained near northern summer solstice (Ls = 74-116, near aphelion) at high northern latitudes (64.7-77.6N), and (2) one set of profiles approaching equinox conditions (Ls = 135- 146) at high southern latitudes (64.7-69.1S). Electron density profiles (95 to 200 km) are examined over a narrow range of solar zenith angles (76.5-86.9 degrees) for local true solar times of (1) 3-4 hours and (2) 12.1 hours. Variations spanning 1-Martian year are specifically examined in the Northern hemisphere.

  15. MGS Radio Science Electron Density Profiles: Interannual Variability and Implications for the Martian Neutral Atmosphere

    Science.gov (United States)

    Bougher, S. W.; Engel, S.; Hinson, D. P.; Murphy, J. R.

    2004-01-01

    Martian electron density profiles provided by the Mars Global Surveyor (MGS) Radio Science (RS) experiment over the 95-200 km altitude range indicate what the height of the electron peak and the longitudinal structure of the peak height are sensitive indicators of the physical state of the Mars lower and upper atmospheres. The present analysis is carried out on five sets of occultation profiles, all at high solar zenith angles (SZA). Variations spanning 2 Martian years are investigated near aphelion conditions at high northern latitudes (64.7 - 77.6 N) making use of four of these data sets. A mean ionospheric peak height of 133.5 - 135 km is obtained near SZA = 78 - 82 deg.; a corresponding mean peak density of 7.3 - 8.5 x l0(exp 4)/ qu cm is also measured during solar moderate conditions at Mars. Strong wave number 2 - 3 oscillations in peak heights are consistently observed as a function of longitude over the 2 Martian years. These observed ionospheric features are remarkably similar during aphelion conditions 1 Martian year apart. This year-to-year repeatability in the thermosphere-ionosphere structure is consistent with that observed in multiyear aphelion temperature data of the Mars lower atmosphere. Coupled Mars general circulation model (MGCM) and Mars thermospheric general circulation model (MTGCM) codes are run for Mars aphelion conditions, yielding mean and longitude variable ionospheric peak heights that reasonably match RS observations. A tidal decomposition of MTGCM thermospheric densities shows that observed ionospheric wave number 3 features are linked to a non-migrating tidal mode with semidiurnal period (sigma = 2) and zonal wave number 1 (s = -1) characteristics. The height of this photochemically determined ionospheric peak should be monitored regularly.

  16. Challenges to Building Surveyors From The Perspectives Of Non Surveyors

    Directory of Open Access Journals (Sweden)

    Isnin Zarina

    2016-01-01

    Full Text Available Awareness on the importance of Building Surveyors in Malaysia is still low as the role and skills of this profession are not fully understood. Although studies indicated that Building Surveyors are still in demand, even without the Building Surveyor Act, many graduates are experiencing inadequate employment opportunities in the current economic situation. Little is known on the views from other stakeholders about BS. This research aims to examine the awareness and opinions on BS in Malaysia amongst construction stakeholders. Questionnaire surveys were collected from 120 respondents from construction, maintenance and insurance companies and interviews were conducted to selected built environment respondents. It was found that awareness and knowledge on BS are still low as they lack information on the profession and professional recognitions. Some views indicated on a major identity crisis for having fragmented and disparate range of modules. The cause may have resulted in problems on public recognition, poor understanding of the surveyor’s skills, and fewer job opportunities. Several suggested the profession to have a clear, coherent and relevant identity, with strong professional structures in order for the profession to survive and gain recognition from the government. Graduates are also recommended to acquire other skills and training in order for them to be significant to the construction industry.

  17. Discovery Mondays: Surveyors' Tools

    CERN Multimedia

    2003-01-01

    Surveyors of all ages, have your rulers and compasses at the ready! This sixth edition of Discovery Monday is your chance to learn about the surveyor's tools - the state of the art in measuring instruments - and see for yourself how they work. With their usual daunting precision, the members of CERN's Surveying Group have prepared some demonstrations and exercises for you to try. Find out the techniques for ensuring accelerator alignment and learn about high-tech metrology systems such as deviation indicators, tracking lasers and total stations. The surveyors will show you how they precisely measure magnet positioning, with accuracy of a few thousandths of a millimetre. You can try your hand at precision measurement using different types of sensor and a modern-day version of the Romans' bubble level, accurate to within a thousandth of a millimetre. You will learn that photogrammetry techniques can transform even a simple digital camera into a remarkable measuring instrument. Finally, you will have a chance t...

  18. Eroded Layered Material in Southwest Utopia Planitia

    Science.gov (United States)

    1999-01-01

    Images from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC)dramatically illustrate that many places on the red planet have outcrops of layered geologic materials. The two pictures above show the remains of layered material inside craters in southwestern Utopia Planitia (see inset for detailed view). These remnant layers indicate that the craters--and perhaps the plains that surround them--were once buried beneath a deposit that has since been eroded away. This theme of layered outcrops and exhumed craters appears to be one of the dominant observations that MGS MOC has made--to date--about Mars. The origin and composition of the layered material--and its ultimate fate once it was largely eroded away--are unknown. Each of the two pictures shown here covers an area about 4 kilometers (2.5 miles)by 6.3 kilometers (3.9 miles). Illumination is from the lower right. These are subframes of a single MOC image acquired in July 1998 during the MGS Science Phasing Orbits imaging campaign. This figure was presented at the 30th Lunar and Planetary Science Conference in Houston, Texas, March 1999. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  19. Surveyor Manual

    DEFF Research Database (Denmark)

    Blyt, Henrik; Hessellund, Regner Bæk

    The project proposes a new training system aiming at the creation of a new profession, the building surveyor, working for the preservation of the existing built stock and extension of its lifetime, by means of regular, expert observation, operation and maintenance. The results of this activity...... in the field, at local and national level. The training system will operate at two different levels, a) for higher-education graduates, mainly architects and engineers, at postgraduate level, providing a new qualification as ‘building surveyor’ and b) for graduates of secondary schools, post-secondary training...... providing the qualification of ‘building maintenance technician’. Being addressed to people seeking jobs, but also to professionals already working in domains connected to the administration and maintenance of building stock, such as local administration, public and private companies owning buildings, SMEs...

  20. A Novel synthesis of MgS and its application as electrode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Wang, Minjuan; Li, Xiang; Gao, Mingxia; Pan, Hongge; Liu, Yongfeng

    2014-01-01

    Highlights: • Nanocrystallite MgS was synthesized by means of a reaction of MgH 2 of S via ball milling. • MgS was firstly investigated as anode material for lithium-ion batteries (LIBs). • MgS with acetylene black introduced by ball milling shows superior electrochemical property. • The mechanisms of the lithium insertion and extraction processes of MgS are discussed. • The work is considered helpful in developing new electrode material for LIBs. - Abstract: MgS was firstly investigated as an anode material for lithium-ion batteries (LIBs). A novel method for the synthesis of nano-sized MgS was conducted, i.e., by means of a reaction of MgH 2 of S via ball milling. Acetylene black (AB) was used as electron conductive agent and introduced by two approaches to the MgS anode material: the one is ball milling AB with the as-prepared MgS derived from MgH 2 and S; the other is pre-milling AB with S and then further milling the mixture with MgH 2 . X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM) and high resolution TEM analyses show that MgS/AB composites with MgS nanocrystallites embedded in the AB matrix are formed via either of the approaches. The MgS anode derived from MgH 2 and the pre-milled S/AB mixture shows high capacity. Capacity fading occurs mainly in the initial several cycles. A capacity of 630 mA h/g is retained after 80 cycles. The electrochemical property is much better than that of the MgS/AB derived from MgS and AB, due to the much homogenous microstructure of the former. The mechanism of the lithium insertion and extraction process of MgS is primarily discussed. The work is considered helpful in developing new synthesis method for MgS and new electrode material for LIBs

  1. Toe of Ganges Chasma Landslide ( 8.0 S, 44.4W)

    Science.gov (United States)

    2001-01-01

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows shear striations, dark dunes banked up against the toe of the slide and over-riding light-toned ripples and boulders on surface of slide. These features can be used to determine quantitative aspects of surface processes.Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  2. Seasonal and Static Gravity Field of Mars from MGS, Mars Odyssey and MRO Radio Science

    Science.gov (United States)

    Genova, Antonio; Goossens, Sander; Lemoine, Frank G.; Mazarico, Erwan; Neumann, Gregory A.; Smith, David E.; Zuber, Maria T.

    2016-01-01

    We present a spherical harmonic solution of the static gravity field of Mars to degree and order 120, GMM-3, that has been calculated using the Deep Space Network tracking data of the NASA Mars missions, Mars Global Surveyor (MGS), Mars Odyssey (ODY), and the Mars Reconnaissance Orbiter (MRO). We have also jointly determined spherical harmonic solutions for the static and time-variable gravity field of Mars, and the Mars k 2 Love numbers, exclusive of the gravity contribution of the atmosphere. Consequently, the retrieved time-varying gravity coefficients and the Love number k 2 solely yield seasonal variations in the mass of the polar caps and the solid tides of Mars, respectively. We obtain a Mars Love number k 2 of 0.1697 +/-0.0027 (3- sigma). The inclusion of MRO tracking data results in improved seasonal gravity field coefficients C 30 and, for the first time, C 50 . Refinements of the atmospheric model in our orbit determination program have allowed us to monitor the odd zonal harmonic C 30 for approx.1.5 solar cycles (16 years). This gravity model shows improved correlations with MOLA topography up to 15% larger at higher harmonics ( l = 60–80) than previous solutions.

  3. Bridging the Gap Between Surveyors and the Geo-Spatial Society

    Science.gov (United States)

    Müller, H.

    2016-06-01

    For many years FIG, the International Association of Surveyors, has been trying to bridge the gap between surveyors and the geospatial society as a whole, with the geospatial industries in particular. Traditionally the surveying profession contributed to the good of society by creating and maintaining highly precise and accurate geospatial data bases, based on an in-depth knowledge of spatial reference frameworks. Furthermore in many countries surveyors may be entitled to make decisions about land divisions and boundaries. By managing information spatially surveyors today develop into the role of geo-data managers, the longer the more. Job assignments in this context include data entry management, data and process quality management, design of formal and informal systems, information management, consultancy, land management, all that in close cooperation with many different stakeholders. Future tasks will include the integration of geospatial information into e-government and e-commerce systems. The list of professional tasks underpins the capabilities of surveyors to contribute to a high quality geospatial data and information management. In that way modern surveyors support the needs of a geo-spatial society. The paper discusses several approaches to define the role of the surveyor within the modern geospatial society.

  4. Determination of the maximum MGS mounting height : phase II detailed analysis with LS-DYNA.

    Science.gov (United States)

    2012-12-01

    Determination of the maximum Midwest Guardrail System (MGS) mounting height was performed in two phases. : Phase I concentrated on crash testing: two full-scale crash tests were performed on the MGS with top-rail mounting heights : of 34 in. (864 mm)...

  5. Surveyor Management of Hospital Accreditation Program: A Thematic Analysis Conducted in Iran.

    Science.gov (United States)

    Teymourzadeh, Ehsan; Ramezani, Mozhdeh; Arab, Mohammad; Rahimi Foroushani, Abbas; Akbari Sari, Ali

    2016-05-01

    The surveyors in hospital accreditation program are considered as the core of accreditation programs. So, the reliability and validity of the accreditation program heavily depend on their performance. This study aimed to identify the dimensions and factors affecting surveyor management of hospital accreditation programs in Iran. This qualitative study used a thematic analysis method, and was performed in Iran in 2014. The study participants included experts in the field of hospital accreditation, and were derived from three groups: 1. Policy-makers, administrators, and surveyors of the accreditation bureau, the ministry of health and medical education, Iranian universities of medical science; 2. Healthcare service providers, and 3. University professors and faculty members. The data were collected using semi-structured in-depth interviews. Following text transcription and control of compliance with the original text, MAXQDA10 software was used to code, classify, and organize the interviews in six stages. The findings from the analysis of 21 interviews were first classified in the form of 1347 semantic units, 11 themes, 17 sub-themes, and 248 codes. These were further discussed by an expert panel, which then resulted in the emergence of seven main themes - selection and recruitment of the surveyor team, organization of the surveyor team, planning to perform surveys, surveyor motivation and retention, surveyor training, surveyor assessment, and recommendations - as well as 27 sub-themes, and 112 codes. The dimensions and variables affecting the surveyors' management were identified and classified on the basis of existing scientific methods in the form of a conceptual framework. Using the results of this study, it would certainly be possible to take a great step toward enhancing the reliability of surveys and the quality and safety of services, while effectively managing accreditation program surveyors.

  6. THERESA FRANCO INSPECTS THE SOLAR PANELS OF THE MARS GLOBAL SURVEYOR

    Science.gov (United States)

    1996-01-01

    Theresa Franco of SPECTROLAB Inc. carefully inspects the solar panels of the Mars Global Surveyor spacecraft, undergoing preflight assembly and checkout in the Payload Hazardous Servicing Facility in KSC's Industrial Area. The four solar array panels will play a crucial role in the Mars Global Surveyor mission by providing the electrical power required to operate the spacecraft and its complement of scientific instruments. The Surveyor is slated for launch November 6 aboard a Delta II expendable launch vehicle. After arriving at the Red Planet in September 1997, the Surveyor will carry out an extensive study of Mars, gathering data about the planet's topography, magnetism, mineral composition and atmosphere.

  7. 5 CFR 532.275 - Special wage schedules for ship surveyors in Puerto Rico.

    Science.gov (United States)

    2010-01-01

    ... in Puerto Rico. 532.275 Section 532.275 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL... schedules for ship surveyors in Puerto Rico. (a) The Department of Defense shall establish special wage schedules for nonsupervisory ship surveyors and supervisory ship surveyors in Puerto Rico. (b) Rates shall...

  8. New transformation mechanism for a zinc-blende to rocksalt phase transformation in MgS

    International Nuclear Information System (INIS)

    Durandurdu, Murat

    2009-01-01

    The stability of the zinc-blende structured MgS is studied using a constant pressure ab initio molecular dynamics technique. A phase transition into a rocksalt structure is observed through the simulation. The zinc-blende to rocksalt phase transformation proceeds via two rhombohedral intermediate phases within R3m (No:160) and R3-barm (No:166) symmetries and does not involve any bond breaking. This mechanism is different from the previously observed mechanism in molecular dynamics simulations. (fast track communication)

  9. Utopia Cracks and Polygons

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-339, 23 April 2003This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a pattern of polygonal cracks and aligned, elliptical pits in western Utopia Planitia. The picture covers an area about 3 km (about 1.9 mi) wide near 44.9oN, 274.7oW. Sunlight illuminates the scene from the left.

  10. Workplace stress experienced by quantity surveyors

    African Journals Online (AJOL)

    Paul (P.A.) Bowen, Department of Construction Economics and Management,. University of Cape Town, Private ..... Explore workplace stress levels among quantity surveyors in the developing nation of ...... London: Free. Association Books.

  11. Experience of the Surveyor Mobile robot at Nine Mile Point

    International Nuclear Information System (INIS)

    Kniazewycz, B.G.; Irving, T.L.

    1987-01-01

    A successful test and evaluation program was recently conducted on a commercial-ready, wireless, remotely operated surveillance system for use in nuclear power plants. This evaluation of the Surveyor Mobile Surveillance System took place at Niagara Mohawk Power Corporation's (NMPC) Nine Mile Point (NMP) Nuclear Power Station. The remotely operated vehicles measures radiation, temperature and relative humidity and provides optical inspection capability. The vehicle is readily maneuvered through 36 inch wide passageways and labyrinth entries and can climb stairs, negotiating 180 degree turns on stair landings. The Surveyor systems consists of a Supervisory Control Station and a rugged, remotely operated, battery-powered vehicle. The Surveyor system is specifically designed to decrease personnel radiation exposure by supplementing the functions of an auxiliary operator or Health Physics Technician to perform periodic component inspections inside particular areas within a nuclear power plant. The purpose of this presentation is to describe the recent efforts, achievements and experiences of the personnel at NMP Unit 1. In particular, this will address the test and evaluation program for the Surveyor Mobile Surveillance Robot

  12. Identifying and Describing Tutor Archetypes: The Pragmatist, the Architect, and the Surveyor

    Science.gov (United States)

    Harootunian, Jeff A.; Quinn, Robert J.

    2008-01-01

    In this article, the authors identify and anecdotally describe three tutor archetypes: the pragmatist, the architect, and the surveyor. These descriptions, based on observations of remedial mathematics tutors at a land-grant university, shed light on a variety of philosophical beliefs regarding and pedagogical approaches to tutoring. An analysis…

  13. The X-Ray Surveyor mission concept study: forging the path to NASA astrophysics 2020 decadal survey prioritization

    Science.gov (United States)

    Gaskin, Jessica; Özel, Feryal; Vikhlinin, Alexey

    2016-07-01

    The X-Ray Surveyor mission concept is unique among those being studied for prioritization in the NASA Astrophysics 2020 Decadal Survey. The X-Ray Surveyor mission will explore the high-energy Universe; providing essential and complimentary observations to the Astronomy Community. The NASA Astrophysics Roadmap (Enduring Quests, Daring Visions) describes the need for an X-Ray Observatory that is capable of addressing topics such as the origin and growth of the first supermassive black holes, galaxy evolution and growth of the cosmic structure, and the origin and evolution of the stars that make up our Universe. To address these scientifically compelling topics and more, an Observatory that exhibits leaps in capability over that of previous X-Ray Observatories in needed. This paper describes the current status of the X-Ray Surveyor Mission Concept Study and the path forward, which includes scientific investigations, technology development, and community participation.

  14. The X-Ray Surveyor Mission Concept Study: Forging the Path to NASA Astrophysics 2020 Decadal Survey Prioritization

    Science.gov (United States)

    Gaskin, Jessica; Ozel, Feryal; Vikhlinin, Alexey

    2016-01-01

    The X-Ray Surveyor mission concept is unique among those being studied for prioritization in the NASA Astrophysics 2020 Decadal Survey. The X-Ray Surveyor mission will explore the high-energy Universe; providing essential and complimentary observations to the Astronomy Community. The NASA Astrophysics Roadmap (Enduring Quests, Daring Visions) describes the need for an X-Ray Observatory that is capable of addressing topics such as the origin and growth of the first supermassive black holes, galaxy evolution and growth of the cosmic structure, and the origin and evolution of the stars that make up our Universe. To address these scientifically compelling topics and more, an Observatory that exhibits leaps in capability over that of previous X-Ray Observatories in needed. This paper describes the current status of the X-Ray Surveyor Mission Concept Study and the path forward, which includes scientific investigations, technology development, and community participation.

  15. Experience with the Surveyor mobile robot in radioactive work environments

    International Nuclear Information System (INIS)

    Kniazewycz, B.G.; Darvish, A.R.; Irving, T.L.

    1986-01-01

    This paper summarizes the development and implementation history of the Surveyor mobile robotic device from November 1985 through August 1986. This two-tracked remotely controlled tetherless device is used to conduct surveillance and inspection and light maintenance missions in nuclear power plants. Surveyor's relatively light weight (<400 lb) can easily be transported manually from location to location. The total maximum payload of the device, which is able to climb 40-deg stairs, is up to 300 lb when transported on a level floor. Surveyor can traverse through 14 in. of water and over 9-in.-high obstacles. Standard accessories include radiation detector, humidity monitor, temperature measurement, sound detection and position/ranging, and a standard video or CCD camera having a wide angle and telephoto lens. These devices are mounted on a 3 degree-of-freedom articulated arm with halogen lights

  16. Correlations Between Variations in Solar EUV and Soft X-Ray Irradiance and Photoelectron Energy Spectra Observed on Mars and Earth

    Science.gov (United States)

    Peterson, W. K.; Brain, D. A.; Mitchell, D. L.; Bailey, S. M.; Chamberlin, P. C.

    2013-01-01

    Solar extreme ultraviolet (EUV; 10-120 nm) and soft X-ray (XUV; 0-10 nm) radiation are major heat sources for the Mars thermosphere as well as the primary source of ionization that creates the ionosphere. In investigations of Mars thermospheric chemistry and dynamics, solar irradiance models are used to account for variations in this radiation. Because of limited proxies, irradiance models do a poor job of tracking the significant variations in irradiance intensity in the EUV and XUV ranges over solar rotation time scales when the Mars-Sun-Earth angle is large. Recent results from Earth observations show that variations in photoelectron energy spectra are useful monitors of EUV and XUV irradiance variability. Here we investigate photoelectron energy spectra observed by the Mars Global Surveyor (MGS) Electron Reflectometer (ER) and the FAST satellite during the interval in 2005 when Earth, Mars, and the Sun were aligned. The Earth photoelectron data in selected bands correlate well with calculations based on 1 nm resolution observations above 27 nm supplemented by broadband observations and a solar model in the 0-27 nm range. At Mars, we find that instrumental and orbital limitations to the identifications of photoelectron energy spectra in MGS/ER data preclude their use as a monitor of solar EUV and XUV variability. However, observations with higher temporal and energy resolution obtained at lower altitudes on Mars might allow the separation of the solar wind and ionospheric components of electron energy spectra so that they could be used as reliable monitors of variations in solar EUV and XUV irradiance than the time shifted, Earth-based, F(10.7) index currently used.

  17. Correlations between variations in solar EUV and soft X-ray irradiance and photoelectron energy spectra observed on Mars and Earth

    Science.gov (United States)

    Peterson, W. K.; Brain, D. A.; Mitchell, D. L.; Bailey, S. M.; Chamberlin, P. C.

    2013-11-01

    extreme ultraviolet (EUV; 10-120 nm) and soft X-ray (XUV; 0-10 nm) radiation are major heat sources for the Mars thermosphere as well as the primary source of ionization that creates the ionosphere. In investigations of Mars thermospheric chemistry and dynamics, solar irradiance models are used to account for variations in this radiation. Because of limited proxies, irradiance models do a poor job of tracking the significant variations in irradiance intensity in the EUV and XUV ranges over solar rotation time scales when the Mars-Sun-Earth angle is large. Recent results from Earth observations show that variations in photoelectron energy spectra are useful monitors of EUV and XUV irradiance variability. Here we investigate photoelectron energy spectra observed by the Mars Global Surveyor (MGS) Electron Reflectometer (ER) and the FAST satellite during the interval in 2005 when Earth, Mars, and the Sun were aligned. The Earth photoelectron data in selected bands correlate well with calculations based on 1 nm resolution observations above 27 nm supplemented by broadband observations and a solar model in the 0-27 nm range. At Mars, we find that instrumental and orbital limitations to the identifications of photoelectron energy spectra in MGS/ER data preclude their use as a monitor of solar EUV and XUV variability. However, observations with higher temporal and energy resolution obtained at lower altitudes on Mars might allow the separation of the solar wind and ionospheric components of electron energy spectra so that they could be used as reliable monitors of variations in solar EUV and XUV irradiance than the time shifted, Earth-based, F10.7 index currently used.

  18. Surveyor mobile surveillance system for hazardous environments

    International Nuclear Information System (INIS)

    Silverman, E.B.; Simmons, R.K.; Kniazewycz, B.G.; Darvish, A.R.; Irving, T.L.

    1987-01-01

    A successful program was recently conducted to test and evaluate a commercial-ready, wireless, remotely operated surveillance system for use in nuclear power plants. This evaluation of the Surveyor mobile surveillance system took place at Niagara Mohawk Power Corporation's Nine Mile Point Nuclear Power Station. The remotely operated vehicle measures radiation, temperature and relative humidity and provides optical inspection capability. The vehicle is readily maneuvered in 36-inch wide passageways and labyrinth entries and can climb stairs, negotiating 180-degree turns on stair landings. The system consists of a supervisory control station and a rugged, remotely-operated, battery-powered vehicle. The surveyor system is specifically designed to decrease personnel radiation exposure by supplementing the functions of an auxiliary operator or wealth physics technician to perform periodic component inspections inside particular areas within a nuclear power plant

  19. 46 CFR 42.05-65 - Surveyor.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Surveyor. 42.05-65 Section 42.05-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of... American Bureau of Shipping or other classification society recognized by the Commandant as the person who...

  20. The surveyors get the measure of the LHC

    CERN Multimedia

    2002-01-01

    The first to start work in the LHC tunnel, the surveyors are precisely marking out the positions of the future accelerator's magnets. A total of 7000 reference points will have to be marked out over two years.

  1. Chemical Analysis of the Moon at the Surveyor VI Landing Site: Preliminary Results.

    Science.gov (United States)

    Turkevich, A L; Patterson, J H; Franzgrote, E J

    1968-06-07

    The alpha-scattering experiment aboard soft-landing Surveyor VI has provided a chemical analysis of the surface of the moon in Sinus Medii. The preliminary results indicate that, within experimental errors, the composition is the same as that found by Surveyor V in Mare Tranquillitatis. This finding suggests that large portions of the lunar maria resemble basalt in composition.

  2. Research Ship Southern Surveyor Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Southern Surveyor Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  3. The Far-Infrared Surveyor (FIS) for AKARI

    NARCIS (Netherlands)

    Kawada, Mitsunobu; Baba, Hajime; Barthel, Peter D.; Clements, David; Cohen, Martin; Doi, Yasuo; Figueredo, Elysandra; Fujiwara, Mikio; Goto, Tomotsugu; Hasegawa, Sunao; Hibi, Yasunori; Hirao, Takanori; Hiromoto, Norihisa; Jeong, Woong-Seob; Kaneda, Hidehiro; Kawai, Toshihide; Kawamura, Akiko; Kester, Do; Kii, Tsuneo; Kobayashi, Hisato; Kwon, Suk Minn; Lee, Hyung Mok; Makiuti, Sin'itirou; Matsuo, Hiroshi; Matsuura, Shuji; Mueller, Thomas G.; Murakami, Noriko; Nagata, Hirohisa; Nakagawa, Takao; Narita, Masanao; Noda, Manabu; Oh, Sang Hoon; Okada, Yoko; Okuda, Haruyuki; Oliver, Sebastian; Ootsubo, Takafumi; Pak, Soojong; Park, Yong-Sun; Pearson, Chris P.; Rowan-Robinson, Michael; Saito, Toshinobu; Salama, Alberto; Sato, Shinji; Savage, Richard S.; Serjeant, Stephen; Shibai, Hiroshi; Shirahata, Mai; Sohn, Jungjoo; Suzuki, Toyoaki; Takagi, Toshinobu; Takahashi, Hidenori; Thomson, Matthew; Usui, Fumihiko; Verdugo, Eva; Watabe, Toyoki; White, Glenn J.; Wang, Lingyu; Yamamura, Issei; Yamauchi, Chisato; Yasuda, Akiko

    2007-01-01

    The Far-Infrared Surveyor (FIS) is one of two focal-plane instruments on the AKARI satellite. FIS has four photometric bands at 65, 90, 140, and 160 mu m, and uses two kinds of array detectors. The FIS arrays and optics are designed to sweep the sky with high spatial resolution and redundancy. The

  4. Polygons in Martian Frost

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-428, 21 July 2003This June 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polygonal pattern developed in seasonal carbon dioxide frost in the martian southern hemisphere. The frost accumulated during the recent southern winter; it is now spring, and the carbon dioxide frost is subliming away. This image is located near 80.4oS, 200.2oW; it is illuminated by sunlight from the upper left, and covers an area 3 km (1.9 mi) across.

  5. Whither the Nigerian Quantity Surveyors in the Information ...

    African Journals Online (AJOL)

    The paucity of information on the computing status of the quantity surveyors in Nigeria have been scanty and without empirical substantiation. The basic platform for entry to the information technology gateway is the acquisition, adoption and utilization of the computer. Baseline information is therefore indispensable for the ...

  6. Rocksalt MgS solar blind ultra-violet detectors

    Directory of Open Access Journals (Sweden)

    Ying-Hoi Lai

    2012-03-01

    Full Text Available Studies using in-situ Auger electron spectroscopy and reflection high energy electron diffraction, and ex-situ high resolution X-ray diffraction and electron backscatter diffraction reveal that a MgS thin film grown directly on a GaAs (100 substrate by molecular beam epitaxy adopts its most stable phase, the rocksalt structure, with a lattice constant of 5.20 Å. A Au/MgS/n+-GaAs (100 Schottky-barrier photodiode was fabricated and its room temperature photoresponse was measured to have a sharp fall-off edge at 235 nm with rejection of more than three orders at 400 nm and higher than five orders at 500 nm, promising for various solar-blind UV detection applications.

  7. Are Quantity Surveyors Competent to Value for Civil Engineering Works? Evaluating QSs' Competencies and Militating Factors

    Science.gov (United States)

    Olawumi, Timothy Oluwatosin; Ayegun, Olaleke Amos

    2016-01-01

    The role of the quantity surveyor is one that is often unclear amongst the general public. This study discussed the competencies of the quantity surveyor in measuring and managing civil engineering works and also carrying out the financial management for civil engineering construction projects; also outlined the various competencies and skills…

  8. The Cosmology Large Angular Scale Surveyor (CLASS): 38 GHz Detector Array of Bolometric Polarimeters

    Science.gov (United States)

    Appel, John W.; Ali, Aamir; Amiri, Mandana; Araujo, Derek; Bennett, Charles L.; Boone, Fletcher; Chan, Manwei; Cho, Hsiao-Mei; Chuss, David T.; Colazo, Felipe; hide

    2014-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) experiment aims to map the polarization of the Cosmic Microwave Background (CMB) at angular scales larger than a few degrees. Operating from Cerro Toco in the Atacama Desert of Chile, it will observe over 65% of the sky at 38, 93, 148, and 217 GHz. In this paper we discuss the design, construction, and characterization of the CLASS 38 GHz detector focal plane, the first ever Q-band bolometric polarimeter array.

  9. The cosmology large angular scale surveyor (CLASS): 38-GHz detector array of bolometric polarimeters

    Science.gov (United States)

    Appel, John W.; Ali, Aamir; Amiri, Mandana; Araujo, Derek; Bennet, Charles L.; Boone, Fletcher; Chan, Manwei; Cho, Hsiao-Mei; Chuss, David T.; Colazo, Felipe; Crowe, Erik; Denis, Kevin; Dünner, Rolando; Eimer, Joseph; Essinger-Hileman, Thomas; Gothe, Dominik; Halpern, Mark; Harrington, Kathleen; Hilton, Gene; Hinshaw, Gary F.; Huang, Caroline; Irwin, Kent; Jones, Glenn; Karakula, John; Kogut, Alan J.; Larson, David; Limon, Michele; Lowry, Lindsay; Marriage, Tobias; Mehrle, Nicholas; Miller, Amber D.; Miller, Nathan; Moseley, Samuel H.; Novak, Giles; Reintsema, Carl; Rostem, Karwan; Stevenson, Thomas; Towner, Deborah; U-Yen, Kongpop; Wagner, Emily; Watts, Duncan; Wollack, Edward; Xu, Zhilei; Zeng, Lingzhen

    2014-07-01

    The Cosmology Large Angular Scale Surveyor (CLASS) experiment aims to map the polarization of the Cosmic Microwave Background (CMB) at angular scales larger than a few degrees. Operating from Cerro Toco in the Atacama Desert of Chile, it will observe over 65% of the sky at 38, 93, 148, and 217 GHz. In this paper we discuss the design, construction, and characterization of the CLASS 38 GHz detector focal plane, the first ever Q-band bolometric polarimeter array.

  10. Thanks to CERN's team of surveyors, the Organization's stand at the Night of Science attracted a large number of visitors : the technology and tools used by the surveyors, such as the Terrameter shown here, attracted many visitors to the CERN stand

    CERN Multimedia

    2004-01-01

    Thanks to CERN's team of surveyors, the Organization's stand at the Night of Science attracted a large number of visitors : the technology and tools used by the surveyors, such as the Terrameter shown here, attracted many visitors to the CERN stand

  11. Surveyor assay to diagnose persistent Müllerian duct syndrome in Miniature Schnauzers.

    Science.gov (United States)

    Kim, Young June; Kwon, Hyuk Jin; Byun, Hyuk Soo; Yeom, Donguk; Choi, Jea-Hong; Kim, Joong-Hyun; Shim, Hosup

    2017-12-31

    Persistent Müllerian duct syndrome (PMDS) is a pseudohermaphroditism in males characterized by the presence of Müllerian duct derivatives. As PMDS dogs often lack clinical symptoms, a molecular diagnosis is essential to identify the syndrome in these animals. In this study, a new molecular method using DNA mismatch-specific Surveyor nuclease was developed. The Surveyor nuclease assay identified the AMHR2 mutation that produced PMDS in a Miniature Schnauzer as accurately as that obtained by using the conventional method based on restriction digestion. As an alternative to the current molecular diagnostic method, the new method may result in increased accuracy when detecting PMDS.

  12. Thermophysical properties of the MER and Beagle II landing site regions on Mars

    Science.gov (United States)

    Jakosky, Bruce M.; Hynek, Brian M.; Pelkey, Shannon M.; Mellon, Michael T.; Martínez-Alonso, Sara; Putzig, Nathaniel E.; Murphy, Nate; Christensen, Philip R.

    2006-08-01

    We analyzed remote-sensing observations of the Isidis Basin, Gusev Crater, and Meridiani Planum landing sites for Beagle II, MER-A Spirit, and MER-B Opportunity spacecraft, respectively. We emphasized the thermophysical properties using daytime and nighttime radiance measurements from the Mars Global Surveyor (MGS) Thermal Emission Spectrometer and Mars Odyssey Thermal Emission Imaging System (THEMIS) and thermal inertias derived from nighttime data sets. THEMIS visible images, MGS Mars Orbiter Camera (MOC) narrow-angle images, and MGS Mars Orbiter Laser Altimeter (MOLA) data are incorporated as well. Additionally, the remote-sensing data were compared with ground-truth at the MER sites. The Isidis Basin surface layer has been shaped by aeolian processes and erosion by slope winds coming off of the southern highlands and funneling through notches between massifs. In the Gusev region, surface materials of contrasting thermophysical properties have been interpreted as rocks or bedrock, duricrust, and dust deposits; these are consistent with a complex geological history dominated by volcanic and aeolian processes. At Meridiani Planum the many layers having different thermophysical and erosional properties suggest periodic deposition of differing sedimentological facies possibly related to clast size, grain orientation and packing, or mineralogy.

  13. Mars Pathfinder and Mars Global Surveyor Outreach Compilation

    Science.gov (United States)

    1999-09-01

    This videotape is a compilation of the best NASA JPL (Jet Propulsion Laboratory) videos of the Mars Pathfinder and Mars Global Surveyor missions. The mission is described using animation and narration as well as some actual footage of the entire sequence of mission events. Included within these animations are the spacecraft orbit insertion; descent to the Mars surface; deployment of the airbags and instruments; and exploration by Sojourner, the Mars rover. JPL activities at spacecraft control during significant mission events are also included at the end. The spacecraft cameras pan the surrounding Mars terrain and film Sojourner traversing the surface and inspecting rocks. A single, brief, processed image of the Cydonia region (Mars face) at an oblique angle from the Mars Global Surveyor is presented. A description of the Mars Pathfinder mission, instruments, landing and deployment process, Mars approach, spacecraft orbit insertion, rover operation are all described using computer animation. Actual color footage of Sojourner as well as a 360 deg pan of the Mars terrain surrounding the spacecraft is provided. Lower quality black and white photography depicting Sojourner traversing the Mars surface and inspecting Martian rocks also is included.

  14. Further Analysis on the Mystery of the Surveyor III Dust Deposits

    Science.gov (United States)

    Metzger, Philip; Hintze, Paul; Trigwell, Steven; Lane, John

    2012-01-01

    The Apollo 12 lunar module (LM) landing near the Surveyor III spacecraft at the end of 1969 has remained the primary experimental verification of the predicted physics of plume ejecta effects from a rocket engine interacting with the surface of the moon. This was made possible by the return of the Surveyor III camera housing by the Apollo 12 astronauts, allowing detailed analysis of the composition of dust deposited by the LM plume. It was soon realized after the initial analysis of the camera housing that the LM plume tended to remove more dust than it had deposited. In the present study, coupons from the camera housing have been reexamined. In addition, plume effects recorded in landing videos from each Apollo mission have been studied for possible clues.

  15. CERN's surveyors are pushing back the frontiers of precision

    CERN Multimedia

    2001-01-01

    Aiming at a target on the other side of the Alps, 730 kilometres from CERN, or controlling the positions of thousands of devices to a precision of one tenth of a millimetre, these are just some of the painstaking tasks undertaken by the surveyors in the Positioning Metrology and Surveying Group. These masters of measurement are pushing precision to its very limit.Go down into the LEP tunnel, walk about half a mile and then try to imagine how you could possibly take precise aim at something hundreds of kilometres away without any reference to the surface. Absurd, you might think? Not entirely, for that, in a nutshell, is the geodetic challenge of the Gran Sasso project. Indeed it is just one of the challenges faced by the surveyors in CERN's Positioning Metrology and Surveying Group, whose task it will be to aim a neutrino beam at a detector located in an underground cavern 732 kilometres away at INFN's Gran Sasso laboratory in Italy. The tools for solving such problems are provided by geodetics, the branch of...

  16. Frost on Dunes

    Science.gov (United States)

    2005-01-01

    18 March 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark dunes on a crater floor during the southern spring. Some of the dunes have frost on their south-facing slopes. Location near: 52.3oS, 326.7oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  17. Mars Thermal Inertia

    Science.gov (United States)

    2001-01-01

    This image shows the global thermal inertia of the Martian surface as measured by the Thermal Emission Spectrometer (TES) instrument on the Mars Global Surveyor. The data were acquired during the first 5000 orbits of the MGS mapping mission. The pattern of inertia variations observed by TES agrees well with the thermal inertia maps made by the Viking Infrared Thermal Mapper experiment, but the TES data shown here are at significantly higher spatial resolution (15 km versus 60 km).The TES instrument was built by Santa Barbara Remote Sensing and is operated by Philip R. Christensen, of Arizona State University, Tempe, AZ.

  18. Polygons on Crater Floor

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-357, 11 May 2003This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a pattern of polygons on the floor of a northern plains impact crater. These landforms are common on crater floors at high latitudes on Mars. Similar polygons occur in the arctic and antarctic regions of Earth, where they indicate the presence and freeze-thaw cycling of ground ice. Whether the polygons on Mars also indicate water ice in the ground is uncertain. The image is located in a crater at 64.8oN, 292.7oW. Sunlight illuminates the scene from the lower left.

  19. an examination of estate surveyors and valuers' perception of flood

    African Journals Online (AJOL)

    Osondu

    2013-11-27

    Nov 27, 2013 ... Key words: Estate Surveyors, Perception, Flood risk, Residential .... islands separated by creeks on a vast lagoon on ... the coastal low land of south western Nigeria – ... tropical continental with rainfall almost ... vegetation is salt water mangrove swamp forest .... have afforded them the opportunity of being.

  20. The Cosmology Large Angular Scale Surveyor (CLASS)

    Science.gov (United States)

    Cleary, Joseph

    2018-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) is an array of four telescopes designed to measure the polarization of the Cosmic Microwave Background. CLASS aims to detect the B-mode polarization from primordial gravitational waves predicted by cosmic inflation theory, as well as the imprint left by reionization upon the CMB E-mode polarization. This will be achieved through a combination of observing strategy and state-of-the-art instrumentation. CLASS is observing 70% of the sky to characterize the CMB at large angular scales, which will measure the entire CMB power spectrum from the reionization peak to the recombination peak. The four telescopes operate at frequencies of 38, 93, 145, and 217 GHz, in order to estimate Galactic synchrotron and dust foregrounds while avoiding atmospheric absorption. CLASS employs rapid polarization modulation to overcome atmospheric and instrumental noise. Polarization sensitive cryogenic detectors with low noise levels provide CLASS the sensitivity required to constrain the tensor-to-scalar ratio down to levels of r ~ 0.01 while also measuring the optical depth the reionization to sample-variance levels. These improved constraints on the optical depth to reionization are required to pin down the mass of neutrinos from complementary cosmological data. CLASS has completed a year of observations at 38 GHz and is in the process of deploying the rest of the telescope array. This poster provides an overview and update on the CLASS science, hardware and survey operations.

  1. Correlates of job satisfaction amongst quantity surveyors in consulting firms in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Henry Ndubuisi Onukwube

    2012-05-01

    Full Text Available Job satisfaction is the sense of well- being, good feeling and positive mental state that emerge in an incumbent worker when his obtained reward consequent upon his performance is congruent with his equitable reward.The aim of this study is to ascertain the levels of job satisfaction amongst quantity surveyors in consulting firms in Lagos, Nigeria. Biographical and job descriptive index questionnaires (JDI were administered to gather the data. The JDI measures job satisfaction on five facets, namely, pay, promotions, supervision, co-workers and the work itself. A total of 100 questionnaires were collected and used for the study. The survey covered quantity surveyors in consulting firms in Lagos and the respondents were selected using stratified random sampling technique. Data collected were analysed using descriptive statistics, correlation matrix, t-test and one way anova. Findings of the study revealed that the respondents were satisfied with the relationship with co-workers, nature of work and the supervision they receive. Major sources of dissatisfaction are promotion and salaries of the respondents. This finding is a bold step and necessary benchmark for resolving major sources of dissatisfaction among quantity surveyors in consulting firms. The roles of other contextual factors on job satisfaction need to be contemplated for future research.

  2. Aram Chaos Rocks

    Science.gov (United States)

    2005-01-01

    8 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcrops of light-toned, sedimentary rock among darker-toned mesas in Aram Chaos. Dark, windblown megaripples -- large ripples -- are also present at this location. Location near: 3.0oN, 21.6oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  3. Northeast Isidis

    Science.gov (United States)

    2005-01-01

    7 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mesa in northeastern Isidis Planitia. The mesa might be a remnant of terrain that once more extensively covered the region. Location near: 20.3oN, 267.7oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  4. Ripple Belt

    Science.gov (United States)

    2006-01-01

    16 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows windblown materials that have collected and been shaped into large ripples in a valley in the Auqakuh Vallis system in northeastern Arabia Terra, Mars. Location near: 29.1oN, 299.6oW Image width: 2 km (1.2 mi) Illumination from: lower left Season: Northern Winter

  5. Microwave Readout to Enable the Imaging Spectrometer for the X-ray Surveyor

    Data.gov (United States)

    National Aeronautics and Space Administration — The X-ray Surveyor mission concept is one of NASA’s four large missions to be studied in the upcoming 2020 Astrophysics Decadal Review. It aims to be a true...

  6. Electronic and structural properties of MgS and CaS

    International Nuclear Information System (INIS)

    Madu, C.A.; Onwuagba, B.N.

    2005-12-01

    The electronic and structural properties of MgS and CaS rocksalt structure are studied with the first principle full Potential Linearized Augmented Plane Wave (FP-LAPW) method. The exchange-correlation potential was calculated within the Generalized Gradient Approximation (GGA) using the Perdew-Burke-Ernzerhof (PBE-GGA) scheme. The scalar relativistic approach was adopted for the valence states, whereas the core states are treated fully relativistically. Energy band structures, density of states and structural parameters of both compounds are presented and discussed in context with the available theoretical and experimental studies. Our results are good and show reasonable agreement with previous results even though sufficient experimental values are not available for more realistic comparison. (author)

  7. Frost in Charitum Montes

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-387, 10 June 2003This is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle view of the Charitum Montes, south of Argyre Planitia, in early June 2003. The seasonal south polar frost cap, composed of carbon dioxide, has been retreating southward through this area since spring began a month ago. The bright features toward the bottom of this picture are surfaces covered by frost. The picture is located near 57oS, 43oW. North is at the top, south is at the bottom. Sunlight illuminates the scene from the upper left. The area shown is about 217 km (135 miles) wide.

  8. Correlates of job satisfaction amongst quantity surveyors in consulting firms in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Henry Ndubuisi Onukwube

    2012-05-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Job satisfaction is the sense of well- being, good feeling and positive mental state that emerge in an incumbent worker when his obtained reward consequent upon his performance is congruent with his equitable reward.The aim of this study is to ascertain the levels of job satisfaction amongst quantity surveyors in consulting firms in Lagos, Nigeria. Biographical and job descriptive index questionnaires (JDI were administered to gather the data. The JDI measures job satisfaction on five facets, namely, pay, promotions, supervision, co-workers and the work itself. A total of 100 questionnaires were collected and used for the study. The survey covered quantity surveyors in consulting firms in Lagos and the respondents were selected using stratified random sampling technique. Data collected were analysed using descriptive statistics, correlation matrix, t-test and one way anova. Findings of the study revealed that the respondents were satisfied with the relationship with co-workers, nature of work and the supervision they receive. Major sources of dissatisfaction are promotion and salaries of the respondents. This finding is a bold step and necessary benchmark for resolving major sources of dissatisfaction among quantity surveyors in consulting firms. The roles of other contextual factors on job satisfaction need to be contemplated for future research.

  9. Rapid Geophysical Surveyor

    International Nuclear Information System (INIS)

    Roybal, L.G.; Carpenter, G.S.; Josten, N.E.

    1993-01-01

    The Rapid Geophysical Surveyor (RGS) is a system designed to rapidly and economically collect closely-spaced geophysical data used for characterization of US Department of Energy waste sites. Geophysical surveys of waste sites are an important first step in the remediation and closure of these sites; especially older sites where historical records are inaccurate and survey benchmarks have changed because of refinements in coordinate controls and datum changes. Closely-spaced data are required to adequately differentiate pits, trenches, and soil vault rows whose edges may be only a few feet from each other. A prototype vehicle designed to collect magnetic field data was built at the Idaho National Engineering Laboratory (INEL) during the summer of 1992. The RGS was funded by the Buried Waste Integrated Demonstration program. This vehicle was demonstrated at the Subsurface Disposal Area (SDA) within the Radioactive Waste Management Complex at the INEL in September 1992. Magnetic data were collected over two areas in the SDA, with a total survey area of about 1.7 acres. Data were collected at a nominal density of 2 1/2 in. along survey lines spaced 1-ft apart. Over 350,000 data points were collected over a 6 day period corresponding to about 185 worker-days using conventional ground survey techniques

  10. The Cosmology Large Angular Scale Surveyor

    Science.gov (United States)

    Harrington, Kathleen; Marriage, Tobias; Ali, Aamir; Appel, John; Bennett, Charles; Boone, Fletcher; Brewer, Michael; Chan, Manwei; Chuss, David T.; Colazo, Felipe; hide

    2016-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) is a four telescope array designed to characterize relic primordial gravitational waves from inflation and the optical depth to reionization through a measurement of the polarized cosmic microwave background (CMB) on the largest angular scales. The frequencies of the four CLASS telescopes, one at 38 GHz, two at 93 GHz, and one dichroic system at 145217 GHz, are chosen to avoid spectral regions of high atmospheric emission and span the minimum of the polarized Galactic foregrounds: synchrotron emission at lower frequencies and dust emission at higher frequencies. Low-noise transition edge sensor detectors and a rapid front-end polarization modulator provide a unique combination of high sensitivity, stability, and control of systematics. The CLASS site, at 5200 m in the Chilean Atacama desert, allows for daily mapping of up to 70% of the sky and enables the characterization of CMB polarization at the largest angular scales. Using this combination of a broad frequency range, large sky coverage, control over systematics, and high sensitivity, CLASS will observe the reionization and recombination peaks of the CMB E- and B-mode power spectra. CLASS will make a cosmic variance limited measurement of the optical depth to reionization and will measure or place upper limits on the tensor-to-scalar ratio, r, down to a level of 0.01 (95% C.L.).

  11. Electric Polygons

    Science.gov (United States)

    2006-01-01

    14 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows erosional remnants of layered rock and large windblown ripples on the floor of a crater in the Tyrrhena Terra region of Mars. The layered rocks are most likely sedimentary. Location near: 68.5oN, 191.8oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

  12. Slam!

    Science.gov (United States)

    2006-01-01

    2 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater on the martian northern plains. This crater is roughly the size of the famous Meteor Crater in Arizona on the North American continent. Location near: 43.0oN, 231.7oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

  13. Influence of the Interplanetary Convective Electric Field on the Distribution of Heavy Pickup Ions Around Mars

    Science.gov (United States)

    Johnson, B. C.; Liemohn, M. W.; Fränz, M.; Ramstad, R.; Stenberg Wieser, G.; Nilsson, H.

    2018-01-01

    This study obtains a statistical representation of 2-15 keV heavy ions outside of the Martian-induced magnetosphere and depicts their organization by the solar wind convective electric field (ESW). The overlap in the lifetime of Mars Global Surveyor (MGS) and Mars Express (MEX) provides a period of nearly three years during which magnetometer data from MGS can be used to estimate the direction of ESW in order to better interpret MEX ion data. In this paper we use MGS estimates of ESW to express MEX ion measurements in Mars-Sun-Electric field (MSE) coordinates. A new methodological technique used in this study is the limitation of the analysis to a particular instrument mode for which the overlap between proton contamination and plume observations is rare. This allows for confident energetic heavy ion identification outside the induced magnetosphere boundary. On the dayside, we observe high count rates of 2-15 keV heavy ions more frequently in the +ESW hemisphere (+ZMSE) than in the -ESW hemisphere, but on the nightside the reverse asymmetry was found. The results are consistent with planetary origin ions being picked up by the solar wind convective electric field. Though a field of view hole hinders quantification of plume fluxes and velocity space, this new energetic heavy ion identification technique means that Mars Express should prove useful in expanding the time period available to assess general plume loss variation with drivers.

  14. Adjusting forest density estimates for surveyor bias in historical tree surveys

    Science.gov (United States)

    Brice B. Hanberry; Jian Yang; John M. Kabrick; Hong S. He

    2012-01-01

    The U.S. General Land Office surveys, conducted between the late 1700s to early 1900s, provide records of trees prior to widespread European and American colonial settlement. However, potential and documented surveyor bias raises questions about the reliability of historical tree density estimates and other metrics based on density estimated from these records. In this...

  15. Observing the Cosmic Microwave Background Polarization with Variable-delay Polarization Modulators for the Cosmology Large Angular Scale Surveyor

    Science.gov (United States)

    Harrington, Kathleen; CLASS Collaboration

    2018-01-01

    The search for inflationary primordial gravitational waves and the optical depth to reionization, both through their imprint on the large angular scale correlations in the polarization of the cosmic microwave background (CMB), has created the need for high sensitivity measurements of polarization across large fractions of the sky at millimeter wavelengths. These measurements are subjected to instrumental and atmospheric 1/f noise, which has motivated the development of polarization modulators to facilitate the rejection of these large systematic effects.Variable-delay polarization modulators (VPMs) are used in the Cosmology Large Angular Scale Surveyor (CLASS) telescopes as the first element in the optical chain to rapidly modulate the incoming polarization. VPMs consist of a linearly polarizing wire grid in front of a moveable flat mirror; varying the distance between the grid and the mirror produces a changing phase shift between polarization states parallel and perpendicular to the grid which modulates Stokes U (linear polarization at 45°) and Stokes V (circular polarization). The reflective and scalable nature of the VPM enables its placement as the first optical element in a reflecting telescope. This simultaneously allows a lock-in style polarization measurement and the separation of sky polarization from any instrumental polarization farther along in the optical chain.The Q-Band CLASS VPM was the first VPM to begin observing the CMB full time in 2016. I will be presenting its design and characterization as well as demonstrating how modulating polarization significantly rejects atmospheric and instrumental long time scale noise.

  16. Utopia Plain

    Science.gov (United States)

    2006-01-01

    5 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a dark-toned, cratered plain in southwest Utopia Planitia. Large, light-toned, windblown ripples reside on the floors of many of the depressions in the scene, including a long, linear, trough. Location near: 30.3oN, 255.3oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  17. Mesa with Apron

    Science.gov (United States)

    2006-01-01

    23 September 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mesa and an impact grater just east of Phlegra Montes. The mesa is the eroded remnant of a once more extensive terrain. An apron of material surrounds the mesa. Location near: 38.5oN, 193.4oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

  18. South Polar Polygons

    Science.gov (United States)

    2005-01-01

    4 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polgyon-cracked surface, into which deep, somewhat kidney-bean-shaped pits have formed. These are landscapes of the martian south polar residual cap. This view was captured during May 2005. Location near: 86.9oS, 5.1oW Image width: 1.5 km (0.9 mi) Illumination from: upper left Season Southern Spring

  19. Buried Craters of Utopia

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-365, 19 May 2003Beneath the northern plains of Mars are numerous buried meteor impact craters. One of the most heavily-cratered areas, although buried, occurs in Utopia Planitia, as shown in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. The history of Mars is complex; impact craters provide a tool by which to understand some of that history. In this case, a very ancient, cratered surface was thinly-buried by younger material that is not cratered at all. This area is near 48.1oN, 228.2oW; less than 180 km (112 mi) west of the Viking 2 lander site. Sunlight illuminates the scene from the lower left.

  20. The ties that bind: Soil surveyor William Edgar Tharp and oceanographic cartographer Marie Tharp

    Science.gov (United States)

    Landa, Edward R.

    The link between soil science and geology is personified in the American father and daughter: soil surveyor William Edgar Tharp (1870-1959) and oceanographic cartographer Marie Tharp (1920-2006). From 1904 to 1935, W.E. Tharp mapped soils in 14 states for the US Department of Agriculture, and campaigned during the late 1920s-early 1930s to raise awareness of the high rates of soil erosion from croplands. The lifestyle of the federal soil surveyor in the United States during the early 20th century involved frequent household moves, and it played a formative role in Marie Tharp’s childhood. Her path to a career in geology was molded by this family experience, by mentors encountered in the classroom, and by social barriers that faced women scientists of that era.

  1. The Cosmology Large Angular Scale Surveyor (CLASS)

    Science.gov (United States)

    Harrington, Kathleen; Marriange, Tobias; Aamir, Ali; Appel, John W.; Bennett, Charles L.; Boone, Fletcher; Brewer, Michael; Chan, Manwei; Chuss, David T.; Colazo, Felipe; hide

    2016-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) is a four telescope array designed to characterize relic primordial gravitational waves from in ation and the optical depth to reionization through a measurement of the polarized cosmic microwave background (CMB) on the largest angular scales. The frequencies of the four CLASS telescopes, one at 38 GHz, two at 93 GHz, and one dichroic system at 145/217 GHz, are chosen to avoid spectral regions of high atmospheric emission and span the minimum of the polarized Galactic foregrounds: synchrotron emission at lower frequencies and dust emission at higher frequencies. Low-noise transition edge sensor detectors and a rapid front-end polarization modulator provide a unique combination of high sensitivity, stability, and control of systematics. The CLASS site, at 5200 m in the Chilean Atacama desert, allows for daily mapping of up to 70% of the sky and enables the characterization of CMB polarization at the largest angular scales. Using this combination of a broad frequency range, large sky coverage, control over systematics, and high sensitivity, CLASS will observe the reionization and recombination peaks of the CMB E- and B-mode power spectra. CLASS will make a cosmic variance limited measurement of the optical depth to reionization and will measure or place upper limits on the tensor-to-scalar ratio, r, down to a level of 0.01 (95% C.L.).

  2. Incomplete Puzzle

    Science.gov (United States)

    2006-01-01

    15 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mid-summer view of a portion of the south polar residual cap of Mars. The large, relatively flat-lying, puzzle-like pieces in this scene are mesas composed largely of solid carbon dioxide. Location near: 85.5oS, 76.8oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  3. Polygons in Utopia

    Science.gov (United States)

    2005-01-01

    14 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a typical view of polygon-cracked and pitted surfaces unique to western Utopia Planitia. No other place on Mars has this appearance. Some Mars scientists have speculated that ground ice may be responsible for these landforms. Location near: 42.3oN, 275.6oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

  4. The surveyors' quest for perfect alignment

    CERN Document Server

    2003-01-01

    Photogrammetry of a CMS endcap and part of the hadronic calorimeter.The structure was covered with targets photographed by digital cameras. Perfect alignment.... Although CERN's surveyors do not claim to achieve it, they are constantly striving for it and deploy all necessary means to come as close as they can. In their highly specialised field of large-scale metrology, the solution lies in geodesy and photogrammetry, both of which are based on increasingly sophisticated instruments and systems. In civil engineering, these techniques are used for non-destructive inspection of bridges, dams and other structures, while industrial applications include dimensional verification and deformation measurement in large mechanical assemblies. The same techniques also come into play for the metrology of research tools such as large telescopes and of course, particle accelerators. Particle physics laboratories are especially demanding customers, and CERN has often asked for the impossible. As a result, the alignment metro...

  5. Chemical Analysis of the Moon at the Surveyor VII Landing Site: Preliminary Results.

    Science.gov (United States)

    Turkevich, A L; Franzgrote, E J; Patterson, J H

    1968-10-04

    The alpha-scattering experiment aboard Surveyor VII has provided a chemical analysis of the moon in the area of the crater Tycho. The preliminary results indicate a chemical composition similar to that already found at two mare sites, but with a lower concentration of elements of the iron group (titanium through copper).

  6. Rapid geophysical surveyor

    International Nuclear Information System (INIS)

    Roybal, L.G.; Carpenter, G.S.; Josten, N.E.

    1993-01-01

    The Rapid Geophysical Surveyor (RGS) is a system designed to rapidly and economically collect closely-spaced geophysical data used for characterization of Department of Energy (DOE) waste sites. Geophysical surveys of waste sites are an important first step in the remediation and closure of these sites; especially older sties where historical records are inaccurate and survey benchmarks have changed due to refinements in coordinate controls and datum changes. Closely-spaced data are required to adequately differentiate pits, trenches, and soil vault rows whose edges may be only a few feet from each other. A prototype vehicle designed to collect magnetic field data was built at the Idaho national Engineering Laboratory (INEL) during the summer of 1992. The RGS was one of several projects funded by the Buried Waste Integrated Demonstration (BWID) program. This vehicle was demonstrated at the Subsurface Disposal Area (SDA) within the Radioactive Waste Management Complex (RWMC) on the INEL in September of 1992. Magnetic data were collected over two areas in the SDA, with a total survey area of about 1.7 acres. Data were collected at a nominal density of 2 1/2 inches along survey lines spaced 1 foot apart. Over 350,000 data points were collected over a 6 day period corresponding to about 185 man-days using conventional ground survey techniques. This report documents the design and demonstration of the RGS concept including the presentation of magnetic data collected at the SDA. The surveys were able to show pit and trench boundaries and determine details of their spatial orientation never before achieved

  7. Early Results from the Odyssey THEMIS Investigation

    Science.gov (United States)

    Christensen, Philip R.; Bandfield, Joshua L.; Bell, James F., III; Hamilton, Victoria E.; Ivanov, Anton; Jakosky, Bruce M.; Kieffer, Hugh H.; Lane, Melissa D.; Malin, Michael C.; McConnochie, Timothy

    2003-01-01

    The Thermal Emission Imaging System (THEMIS) began studying the surface and atmosphere of Mars in February, 2002 using thermal infrared (IR) multi-spectral imaging between 6.5 and 15 m, and visible/near-IR images from 450 to 850 nm. The infrared observations continue a long series of spacecraft observations of Mars, including the Mariner 6/7 Infrared Spectrometer, the Mariner 9 Infrared Interferometer Spectrometer (IRIS), the Viking Infrared Thermal Mapper (IRTM) investigations, the Phobos Termoscan, and the Mars Global Surveyor Thermal Emission Spectrometer (MGS TES). The THEMIS investigation's specific objectives are to: (1) determine the mineralogy of localized deposits associated with hydrothermal or sub-aqueous environments, and to identify future landing sites likely to represent these environments; (2) search for thermal anomalies associated with active sub-surface hydrothermal systems; (3) study small-scale geologic processes and landing site characteristics using morphologic and thermophysical properties; (4) investigate polar cap processes at all seasons; and (5) provide a high spatial resolution link to the global hyperspectral mineral mapping from the TES investigation. THEMIS provides substantially higher spatial resolution IR multi-spectral images to complement TES hyperspectral (143-band) global mapping, and regional visible imaging at scales intermediate between the Viking and MGS cameras.

  8. CERN’s surveyors send sparks flying

    CERN Multimedia

    Anaïs Schaeffer

    2013-01-01

    A few weeks ago, we published an article on the three-dimensional laser scanner technique used at CERN to produce 3D images of the LHC tunnels and experiments (see the article here). Photogrammetry is another technique in the CERN surveyors’ arsenal.   The ATLAS wheel during a photogrammetry measurement campaign. The white spots (see red arrows) dotted across the wheel are the retro-reflective "dot" targets. Used in a number of fields including topography, architecture, geology and archaeology, photogrammetry is a stereoscopy technique whereby 2D images taken from different angles can be used to reconstruct a 3D image of an object. Surveyors at CERN have been using this technique for over 15 years as a way of gaining precise information on the shape, size, deformation and position of the LHC detectors and their composite elements. The photogrammetry used at CERN is relatively “light” in terms of the equipment required, w...

  9. Constraining the 0-20 km Vertical Profile of Water Vapor in the Martian Atmosphere with MGS-TES Limb Sounding

    Science.gov (United States)

    McConnochie, T. H.; Smith, M. D.; McDonald, G. D.

    2016-12-01

    The vertical profile of water vapor in the lower atmosphere of Mars is a crucial but poorly-measured detail of the water cycle. Most of our existing water vapor data sets (e.g. Smith, 2002, JGR 107; Smith et al., 2009, JGR 114; Maltagliati et al., 2011, Icarus 213) rely on the traditional assumption of uniform mass mixing from the surface up to a saturation level, but GCM models (Richardson et al., 2002, JGR 107; Navarro et al., 2014, JGR 119) imply that this is not the case in at least some important seasons and locations. For example at the equator during northern summer the water vapor mixing ratio in aforementioned GCMs increases upwards by a factor of two to three in the bottom scale height. This might influence the accuracy of existing precipitable water column (PWC) data sets. Even if not, the correct vertical distribution is critical for determining the extent to which high-altitude cold trapping interferes with inter-hemispheric transport, and its details in the lowest scale heights will be a critical test of the accuracy of modeled water vapor transport. Meanwhile attempts to understand apparent interactions of water vapor with surface soils (e.g. Ojha et al. 2015, Nature Geoscience 8; Savijärvi et al., 2016, Icarus 265) need an estimate for the amount of water vapor in the boundary layer, and existing PWC data sets can't provide this unless the lower atmospheric vertical distribution is known or constrained. Maltagliati et al. (2013, Icarus 223) have obtained vertical profiles of water vapor at higher altitudes with SPICAM on Mars Express, but these are commonly limited to altitudes greater 20 km and they never extend below 10 km. We have previously used Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) limb-sounding to measure the vertical profile of water vapor (e.g. McConnochie and Smith, 2009, Fall AGU #P54B-06), but these preliminary results were clearly not quantitatively accurate in the lower atmosphere. We will present improved TES

  10. Professional Risk Assessment on the Workplace of Surface Surveyor Employed in Measuring-Geological Department of Coalmine

    Science.gov (United States)

    Matuszewska, Ewa; Orwat, Justyna

    2016-06-01

    In this article were shown the identification of threats and the assessment of occupational risk for the surface surveyor by using the Five Steps method and taking into account the health state of workers.

  11. Impact of revisions to the F-Tag 309 surveyors' interpretive guidelines on pain management among nursing home residents.

    Science.gov (United States)

    Lapane, Kate L; Quilliam, Brian J; Chow, Wing; Kim, Myoung S

    2012-05-01

    On 31 March 2009, the US Centers for Medicare & Medicaid Services (CMS) provided revised guidance for meeting compliance in the evaluation and management of pain in nursing home residents, known as F-Tag 309. The aim of the study was to estimate the extent to which implementation of revisions to the surveyors' interpretive guidelines for F-Tag 309 improved recognition and management of pain among nursing home residents. The impact of the revisions to guidance on F-Tag 309 on pain in nursing home residents was investigated. The study was quasi-experimental in design and included 174 for-profit nursing homes in 19 US states. Nursing home residents with ≥2 Minimum Data Set (MDS) assessments between 1 January 2007 and 30 March 2009 (before the revisions to the guidelines; n = 8449) and between 31 March 2009 and 31 December 2009 (after the revisions; n = 1400) were included. The MDS assessments provided information on pain, analgesic use and cognitive, functional and emotional status. Separate logistic regression models that adjusted for clustering effects of residents residing in nursing homes provided estimates of the relationship between the implementation of the revisions to F-Tag 309 and the prevalence of pain and its management. Pain was more likely to be documented in the period after the revisions were implemented. The odds of pain being documented on at least one of two consecutive MDS assessments increased after the revisions to the guidelines were implemented (adjusted odds ratio [OR] 1.15; 95% confidence interval [CI] 1.01, 1.31). Increases in scheduled analgesic prescription were observed in the post-revision era (adjusted OR 1.38; 95% CI 1.21,1.57). The implementation of revisions to the surveyors' interpretive guidelines for F-Tag 309 improved recognition and management of pain as well as analgesic use in nursing home residents with documented non-cancer pain. Use of directed language as part of the surveyors' interpretive guidelines may be a

  12. The importance of standardized observations to evaluate nutritional care quality in the survey process.

    Science.gov (United States)

    Schnelle, John F; Bertrand, Rosanna; Hurd, Donna; White, Alan; Squires, David; Feuerberg, Marvin; Hickey, Kelly; Simmons, Sandra F

    2009-10-01

    Guidelines written for government surveyors who assess nursing home (NH) compliance with federal standards contain instructions to observe the quality of mealtime assistance. However, these instructions are vague and no protocol is provided for surveyors to record observational data. This study compared government survey staff observations of mealtime assistance quality to observations by research staff using a standardized protocol that met basic standards for accurate behavioral measurement. Survey staff used either the observation instructions in the standard survey process or those written for the revised Quality Improvement Survey (QIS). Trained research staff observed mealtime care in 20 NHs in 5 states during the same time period that survey staff evaluated care in the same facilities, although it could not be determined if survey and research staff observed the same residents during the same meals. Ten NHs were evaluated by government surveyors using the QIS survey instructions and 10 NHs were evaluated by surveyors using the standard survey instructions. Research staff observations using a standardized observation protocol identified a higher proportion of residents receiving inadequate feeding assistance during meals relative to survey staff using either the standard or QIS survey instructions. For example, more than 50% of the residents who ate less than half of their meals based on research staff observation were not offered an alternative to the served meal, and the lack of alternatives, or meal substitutions, was common in all 20 NHs. In comparison, the QIS survey teams documented only 2 instances when meal substitutes were not offered in 10 NHs and the standard survey teams documented no instances in 10 NHs. Standardized mealtime observations by research staff revealed feeding assistance care quality issues in all 20 study NHs. Surveyors following the instructions in either the standard or revised QIS surveys did not detect most of these care quality

  13. Cosmology Large Angular Scale Surveyor (CLASS) Focal Plane Development

    Science.gov (United States)

    Chuss, D. T.; Ali, A.; Amiri, M.; Appel, J.; Bennett, C. L.; Colazo, F.; Denis, K. L.; Dunner, R.; Essinger-Hileman, T.; Eimer, J.; hide

    2015-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) will measure the polarization of the Cosmic Microwave Background to search for and characterize the polarized signature of inflation. CLASS will operate from the Atacama Desert and observe approx.70% of the sky. A variable-delay polarization modulator provides modulation of the polarization at approx.10Hz to suppress the 1/f noise of the atmosphere and enable the measurement of the large angular scale polarization modes. The measurement of the inflationary signal across angular scales that spans both the recombination and reionization features allows a test of the predicted shape of the polarized angular power spectra in addition to a measurement of the energy scale of inflation. CLASS is an array of telescopes covering frequencies of 38, 93, 148, and 217 GHz. These frequencies straddle the foreground minimum and thus allow the extraction of foregrounds from the primordial signal. Each focal plane contains feedhorn-coupled transition-edge sensors that simultaneously detect two orthogonal linear polarizations. The use of single-crystal silicon as the dielectric for the on-chip transmission lines enables both high efficiency and uniformity in fabrication. Integrated band definition has been implemented that both controls the bandpass of the single-mode transmission on the chip and prevents stray light from coupling to the detectors.

  14. Winter Frost and Fog

    Science.gov (United States)

    2005-01-01

    This somewhat oblique blue wide angle Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the 174 km (108 mi) diameter crater, Terby, and its vicinity in December 2004. Located north of Hellas, this region can be covered with seasonal frost and ground-hugging fog, even in the afternoon, despite being north of 30oS. The subtle, wavy pattern is a manifestation of fog. Location near: 28oS, 286oW Illumination from: upper left Season: Southern Winter

  15. Enhanced by Frost

    Science.gov (United States)

    2005-01-01

    30 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcrops of south polar layered terrain. Their appearance in this July 2005 springtime image is enhanced by bright patches of carbon dioxide frost. The frost is left over from the previous southern winter season; by summer, the frost would be gone. Location near: 84.6oS, 203.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  16. Sand Dunes with Frost

    Science.gov (United States)

    2004-01-01

    9 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of frost-covered sand dunes in the north polar region of Mars in early spring, 2004. The dunes indicate wind transport of sand from left to right (west to east). These landforms are located near 78.1oN, 220.8oW. This picture is illuminated by sunlight from the lower left and covers an area about 3 km (1.9 mi) across.

  17. Polar Polygons

    Science.gov (United States)

    2005-01-01

    18 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark-outlined polygons on a frost-covered surface in the south polar region of Mars. In summer, this surface would not be bright and the polygons would not have dark outlines--these are a product of the presence of seasonal frost. Location near: 77.2oS, 204.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  18. Core-Log-Seismic investigations of the Surveyor Fan and Channel system during the Pleistocene; IODP Exp. 341

    Science.gov (United States)

    Somchat, K.; Reece, R.; Gulick, S. P. S.

    2017-12-01

    The Chugach-St. Elias mountain range is the product of the ongoing subduction and collision of the Yakutat microplate with the North America Plate. The presence of this high topography close to the shoreline creates a unique source-to-sink system in which glacial eroded sediment is transported directly to the sea and preserved offshore in a deep sea fan without intervening storage. Surveyor Fan and Channel system is the product of this system. In this study we will focus on the four tributary channels that form at the head of the Surveyor Channel complex and merge into the main channel trunk 200 km from the shelf edge. We integrated drill core and 2D seismic reflection data to study the evolution of these tributaries in order to decipher glacial history along the southern Alaskan margin since the mid-Pleistocene (1.2 Ma). An age model from Integrated Ocean Drilling Program Expedition 341 Site U1418 provides a higher resolution chronology of sediment delivery to the Surveyor Fan than previous studies. We regionally mapped the seismic subunits previously identified by Exp. 341 scientists starting from Site U1418 and analyzed regional patterns of sediment deposition. Channel migrations are observable between 1.2-0.5 Ma which could be the result of increasing glacial ice volume onshore due to onset of the MPT. Two-way travel time (isopach) maps of the three subunits show that sediment depocenter began to move eastward since 1.2 Ma with a trend of overall sediment flux increase in all tributary channels. Changes in sediment flux in each system represent the changes in volume of glacial ice over successive glacial intervals. Additionally, seismic analysis of channel geomorphology shows that each system contains distinct geomorphological evolutions that respond to the glacially eroded sediment flux at different times. Since glacial erosional processes is the driver of this source-to-sink system, a history of glacial ice onshore since the Pleistocene can be inferred from

  19. Cracks in Utopia

    Science.gov (United States)

    1999-01-01

    Many of the craters found on the northern plains of Mars have been partly filled or buried by some material (possibly sediment). The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image presented here (MOC2-136b, above left) shows a high-resolution view of a tiny portion of the floor of one of these northern plains craters. The crater, located in Utopia Planitia at 44oN, 258oW, is shown on the right (MOC2-136a)with a small white box to indicate the location of the MOC image. The MOC image reveals that the material covering the floor of this crater is cracked and pitted. The origin and source of material that has been deposited in this crater is unknown.The MOC image was acquired in June 1999 and covers an area only 1.1 kilometers (0.7 miles) wide at a resolution of 1.8 meters (6 feet) per pixel. The context picture is a mosaic of Viking 2 orbiter images 010B53 and 010B55, taken in 1976. Both images are illuminated from the left. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  20. Variability in Morphology and Thermophysical Properties of Pitted Cones in Acidalia Planitia and Cydonia Mensae

    Science.gov (United States)

    Farrand, W. H.; Gaddis, L. R.; Blundell, S.

    2004-01-01

    The northern plains of Mars contain a number of unique landforms and are unique in terms of their topography and composition . Much of the speculation about the northern plains centers on whether there was ever a northern ocean, and if there was, was it long-lived or ephemeral? The northern plains also hosts the Vastitas Borealis Formation which has been variously interpreted as the residue from a northern ocean , and pre-existing material reworked by cold-weather processes . In this work we examine a set of unusual features resident on the northern plains, the pitted cones originally recognized in Viking data . Our focus is on the pitted cones in Acidalia and Cydonia regions. The pitted cones of the northern plains have been hypothesized as being equivalent to terrestrial cinder cones , rootless cones , pingos , and mud volcanoes . To examine the Acidalia and Cydonia regions, multispectral data from the Mars Odyssey THEMIS, gridded topography from Mars Global Surveyor (MGS) MOLA, images from MGS MOC, and mineralogic and thermal inertia information from MGS TES have been assembled in a Geographic Information System. Analysis of MOC Narrow Angle camera images

  1. Arsia Mons Spiral Cloud

    Science.gov (United States)

    2002-01-01

    One of the benefits of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Extended Mission is the opportunity to observe how the planet's weather changes during a second full martian year. This picture of Arsia Mons was taken June 19, 2001; southern spring equinox occurred the same day. Arsia Mons is a volcano nearly large enough to cover the state of New Mexico. On this particular day (the first day of Spring), the MOC wide angle cameras documented an unusual spiral-shaped cloud within the 110 km (68 mi) diameter caldera--the summit crater--of the giant volcano. Because the cloud is bright both in the red and blue images acquired by the wide angle cameras, it probably consisted mostly of fine dust grains. The cloud's spin may have been induced by winds off the inner slopes of the volcano's caldera walls resulting from the temperature differences between the walls and the caldera floor, or by a vortex as winds blew up and over the caldera. Similar spiral clouds were seen inside the caldera for several days; we don't know if this was a single cloud that persisted throughout that time or one that regenerated each afternoon. Sunlight illuminates this scene from the left/upper left.Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  2. Pits on Ascraeus

    Science.gov (United States)

    2005-01-01

    24 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows collapse pits and troughs on the lower northeast flank of the giant martian volcano, Ascraeus Mons. Layers of volcanic rock are evident in some of the pit and valley walls, and boulders the size of houses and trucks that were liberated from these walls by gravity can be seen on the floors of the depressions. Location near: 13.6oN, 102.6oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  3. Polygons and Craters

    Science.gov (United States)

    2005-01-01

    3 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygons enhanced by subliming seasonal frost in the martian south polar region. Polygons similar to these occur in frozen ground at high latitudes on Earth, suggesting that perhaps their presence on Mars is also a sign that there is or once was ice in the shallow subsurface. The circular features are degraded meteor impact craters. Location near: 72.2oS, 310.3oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  4. 'Surveyor': An Underwater System for Threat Material Detection

    International Nuclear Information System (INIS)

    Valkovic, Vladivoj; Sudac, Davorin; Nad, Karlo; Obhodas, Jasmina; Matika, Dario; Kollar, Robert

    2010-01-01

    The bottoms of the coastal seas, and oceans as well, are contaminated by many man-made objects including a variety of ammunition. This contamination is world wide spread with some areas being highly polluted presenting a serious threat to local population and to visitors as well. All littoral nations are investing lots of effort into the remediation of their coastal areas. Once the presence of the anomaly on the bottom of the shallow coastal sea water is confirmed (by visual identification and by using one or several sensors, namely magnetometer, sonar and optical cameras) it is necessary to establish if it contains explosive/chemical warfare charge. In our work we propose this to be performed by using neutron sensor installed within an underwater vessel - 'Surveyor'. When positioned above the object, or to its side, the system inspects the object for the presence of the threat material by using alpha particle tagged neutrons from the sealed tube d+t neutron generator. (author)

  5. Quality assurance systems – the difficulties in providing a global unified system for Surveyors

    OpenAIRE

    Goodhead, Tim

    2012-01-01

    This paper will analyse the difficulties in providing a global quality assurance system for Surveyors. Using case studies from the United Kingdom and elsewhere opportunities for harmonising Quality Assurance systems will be explored. The difficulties in moving towards common quality assurance systems will be analysed. Possible alternatives in the form of the development a knowledge bank of mutual agreements and top up qualifications will be investigated. The paper also looks at the role of FI...

  6. Polygons near Lyot Crater

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-564, 4 December 2003This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows patterned ground, arranged in the form of polygons, on the undulating plains associated with ejecta from the Lyot impact crater on the martian northern plains. This picture was acquired in October 2003 and shows that the polygon margins are ridges with large boulders--shown here as dark dots--on them. On Earth, polygon patterns like this are created in arctic and antarctic regions where there is ice in the ground. The seasonal and longer-term cycles of freezing and thawing of the ice-rich ground cause these features to form over time. Whether the same is true for Mars is unknown. The polygons are located near 54.6oN, 326.6oW. The image covers an area 3 km (1.9 mi) wide and is illuminated from the lower left.

  7. Spiders from Mars?

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-426, 19 July 2003No, this is not a picture of a giant, martian spider web. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a plethora of polygonal features on the floor of a northern hemisphere impact crater near 65.6oN, 327.7oW. The picture was acquired during spring, after the seasonal carbon dioxide frost cap had largely migrated through the region. At the time the picture was taken, remnants of seasonal frost remained on the crater rim and on the edges of the troughs that bound each of the polygons. Frost often provides a helpful hint as to where polygons and patterned ground occur. The polygons, if they were on Earth, would indicate the presence of freeze-thaw cycles in ground ice. Although uncertain, the same might be true of Mars. Sunlight illuminates the scene from the lower left.

  8. Waves in the Martian Atmosphere: Results from MGS Radio Occultations

    Science.gov (United States)

    Flasar, F. M.; Hinson, D. P.; Tyler, G. L.

    1999-01-01

    Temperatures retrieved from Mars Global Surveyor radio occultations have been searched for evidence of waves. Emphasis has been on the initial series of occultations between 29 deg N and 64 deg S, obtained during the early martian southern summer, L(sub s) = 264 deg - 308 deg. The profiles exhibit an undulatory behavior that is suggestive of vertically propagating waves. wavelengths approximately 10 km are often dominant, but structure on smaller scales is evident. The undulatory structure is most pronounced between latitudes 29 deg N and 10 deg S, usually in regions of "interesting" topography, e.g., in the Tharsis region and near the edge of Syrtis Major. Several temperature profiles, particularly within 30 deg of the equator, exhibit lapse rates that locally become superadiabatic near the 0.4-mbar level or at higher altitudes. This implies that the waves are "breaking" and depositing horizontal momentum into the atmosphere. Such a deposition may play an important role in modulating the atmospheric winds, and characterizing the spatial and temporal distribution of these momentum transfers can provide important clues to understanding how the global circulation is maintained.

  9. Direct imaging and new technologies to search for substellar companions around MGs cool dwarfs

    Directory of Open Access Journals (Sweden)

    Burningham B.

    2011-07-01

    Full Text Available We describe here our project based in a search for sub-stellar companions (brown dwarfs and exo-planets around young ultra-cool dwarfs (UCDs and characterise their properties. We will use current and future technology (high contrast imaging, high-precision Doppler determinations from the ground and space (VLT, ELT and JWST, to find companions to young objects. Members of young moving groups (MGs have clear advantages in this field. We compiled a catalogue of young UCD objects and studied their membership to five known young moving groups: Local Association (Pleiades moving group, 20–150 Myr, Ursa Mayor group (Sirius supercluster, 300 Myr, Hyades supercluster (600 Myr, IC 2391 supercluster (35 Myr and Castor moving group (200 Myr. To assess them as members we used different kinematic and spectroscopic criteria.

  10. The PhotoElectron Boundary as observed by MAVEN instruments

    Science.gov (United States)

    Garnier, P.; Steckiewicz, M.; Mazelle, C. X.; Xu, S.; Mitchell, D. L.; Holmberg, M.; Halekas, J. S.; Andersson, L.; Brain, D.; Connerney, J. E. P.; Espley, J. R.; Lillis, R. J.; Luhmann, J. G.; Savaud, J. A.; Jakosky, B. M.

    2017-12-01

    Photoelectron peaks in the 20-30 eV energy range are commonly observed in planetary atmospheres (Earth, Mars, Titan...), produced by the intense photoionization from solar 30.4 nm photons. At Mars, these photoelectrons result from the ionization of CO2 and O atmospheric neutrals, and are known to escape the planet down its tail, making them tracers for the atmospheric escape (Frahm et al., 2006). Furthermore, their presence or absence allows us to define the so-called PhotoElectron Boundary (PEB), that separates the sunlit photoelectron-dominated ionosphere from the solar wind controlled environment, as initially observed by the Mars Global Surveyor (MGS) MAG/ER instrument (Mitchell et al. (2000, 2001). We provide here a detailed statistical analysis of the location and properties of the PEB based on the Mars Atmosphere and Volatile Evolution (MAVEN) mission electron and magnetic field data. Our dataset includes 1696 dayside PEB crossings obtained from September 2014 until May 2016 (the observations of escaping photoelectrons in the wake being not included). The PEB appears as mostly sensitive to the solar wind dynamic and crustal magnetic fields pressures, for which a quantitative dependance is derived and compared with two other important boundaries : the bow shock and magnetic pileup boundary. The PEB altitude is highly variable, leading to a variable wake cross section for escape (up to +- 50%), which is important for deriving global escape rates from in situ photoelectron escape rates. The PEB is not always sharp, and is, despite a strong variability, characterized on average by : a magnetic field topology typical for the edge of the Magnetic Pile Up Region above it, more field aligned fluxes above than below, and a clear change of the altitude dependence of both electron fluxes and total density (that appears different from the ionopause). The PEB thus appears as a transition region between two plasma and field configurations which is determined by the

  11. Crater in Utopia

    Science.gov (United States)

    2004-01-01

    23 March 2004 Craters of the martian northern plains tend to be somewhat shallow because material has filled them in. Their ejecta blankets, too, are often covered by younger materials. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example--a crater in Utopia Planitia near 43.7oN, 227.3oW. Erosion has roughened some of the surfaces of the material that filled the crater and covered its ejecta deposit. The picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the lower left.

  12. CLASS: The Cosmology Large Angular Scale Surveyor

    Science.gov (United States)

    Essinger-Hileman, Thomas; Ali, Aamir; Amiri, Mandana; Appel, John W.; Araujo, Derek; Bennett, Charles L.; Boone, Fletcher; Chan, Manwei; Cho, Hsiao-Mei; Chuss, David T.; hide

    2014-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the signature of a gravitational wave background from inflation in the polarization of the cosmic microwave background (CMB). CLASS is a multi-frequency array of four telescopes operating from a high-altitude site in the Atacama Desert in Chile. CLASS will survey 70% of the sky in four frequency bands centered at 38, 93, 148, and 217 GHz, which are chosen to straddle the Galactic-foreground minimum while avoiding strong atmospheric emission lines. This broad frequency coverage ensures that CLASS can distinguish Galactic emission from the CMB. The sky fraction of the CLASS survey will allow the full shape of the primordial B-mode power spectrum to be characterized, including the signal from reionization at low-length. Its unique combination of large sky coverage, control of systematic errors, and high sensitivity will allow CLASS to measure or place upper limits on the tensor-to-scalar ratio at a level of r = 0:01 and make a cosmic-variance-limited measurement of the optical depth to the surface of last scattering, tau. (c) (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  13. High-Resolution and Lightweight X-ray Optics for the X-Ray Surveyor

    Science.gov (United States)

    Zhang, William

    Envisioned in "Enduring Quest, Daring Visions" and under study by NASA as a potential major mission for the 2020s, the X-ray Surveyor mission will likely impose three requirements on its optics: (1) high angular resolution: 0.5 PSF, (2) large effective area: e10,000 cm2 or more, and (3) affordable production cost: $500M. We propose a technology that can meet these requirements by 2020. It will help the X-ray Surveyor secure the endorsement of the coming decadal survey and enable its implementation following WFIRST. The technology comprises four elements: (1) fabrication of lightweight single crystal silicon mirrors, (2) coating these mirrors with iridium to maximize effective area without figure degradation, (3) alignment and bonding of these mirrors to form meta-shells that will be integrated to make a mirror assembly, and (4) systems engineering to ensure that the mirror assembly meet all science performance and spaceflight environmental requirements. This approach grows out of our existing approach based on glass slumping. Using glass slumping technology, we have been able to routinely build and test mirror modules of 10half-power diameter (HPD). While comparable in HPD to XMM-Newtons electroformed nickel mirrors, these mirror modules are 10 times lighter. Likewise, while comparable in weight to Suzakus epoxy-replicated aluminum foil mirrors, these modules have 10 times better HPD. These modules represent the current state of the art of lightweight X-ray optics. Although both successful and mature, the glass slumping technology has reached its limit and cannot achieve sub-arc second HPD. Therefore, we are pursuing the new approach based on polishing single crystal silicon. The new approach will enable the building and testing of mirror modules, called meta-shells, capable of 3HPD by 2018 and 1HPD by 2020, and has the potential to reach diffraction limits ( 0.1) in the 2020s.

  14. Eos Chaos Rocks

    Science.gov (United States)

    2006-01-01

    11 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered rock outcrops in Eos Chaos, located near the east end of the Valles Marineris trough system. The outcrops occur in the form of a distinct, circular butte (upper half of image) and a high slope (lower half of image). The rocks might be sedimentary rocks, similar to those found elsewhere exposed in the Valles Marineris system and the chaotic terrain to the east of the region. Location near: 12.9oS, 49.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  15. Polygons in Seasonal Frost

    Science.gov (United States)

    2004-01-01

    8 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a summertime scene in the south polar region of the red planet. A patch of bright frost--possibly water ice--is seen in the lower third of the image. Polygon patterns that have developed in the ice as it sublimes away can be seen; these are not evident in the defrosted surfaces, so they are thought to have formed in the frost. This image is located near 82.6oS, 352.5oW. Sunlight illuminates this scene from the upper left; the image covers an area 3 km (1.9 mi) wide.

  16. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from SOUTHERN SURVEYOR in the North Pacific Ocean and South Pacific Ocean from 2009-02-03 to 2009-03-24 (NODC Accession 0108082)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0108082 includes chemical, discrete sample, physical and profile data collected from SOUTHERN SURVEYOR in the North Pacific Ocean and South Pacific...

  17. Glacial and tectonic influence on terrestrial organic carbon delivery to high latitude deep marine systems: IODP Site U1417, Surveyor Fan, Gulf of Alaska

    Science.gov (United States)

    Childress, L. B.; Ridgway, K. D.

    2014-12-01

    Glacial and tectonic processes on active margins are intrinsically coupled to the transport of sediment and associated organic carbon (OC). Glaciation/deglaciation and the formation of ice sheets can alter the quantity and composition of OC delivered to the marine environment. Over geologic time scales (>1 Ma), exhumation and mass wasting of sedimentary rock from uplifted accretionary wedges inject recycled OC (e.g. kerogen), along with modern OC into the marine environment. The sedimentary record of glacial and tectonic processes along the southern Alaska margin is particularly well preserved at Integrated Ocean Drilling Program (IODP) Site U1417. Lithofacies of Site U1417 can be divided into 3 sedimentary packages that we interpret as linked to the onset of tidewater glaciation along, and tectonic convergence of the Yakutat Terrane with, the continental margin of northwestern Canada and southern Alaska. Based on previous studies linking the development of the Cordilleran Ice Sheet and the movement of the Yakutat Terrane to the development of the Surveyor Fan System, we hypothesize biogeochemical variations in the deposited sediments as a result of changing provenance. Preservation of terrestrial OC that has been documented in sediments of the Alaskan continental shelf margin and sediment routing through the deep-sea Surveyor Channel from the Pleistocene to modern time implies a long-term conduit for this OC to reach the distal portion of the Surveyor Fan system. To correlate marine deposits with terrestrial formations, bulk geochemical and detailed biomarker analyses are used to delineate source material. Preliminary bulk OC content and stable carbon isotope analyses of the Yakataga, Poul Creek, and Kultheith Fms. reveal notable differences. Detailed biomarker analysis by pyrolysis-gas chromatograph-mass spectrometry has revealed further differences between the three primary formations. Using the biogeochemical fingerprints of the Yakataga, Poul Creek, and coal

  18. The Transient High Energy Sky and Early Universe Surveyor

    Science.gov (United States)

    O'Brien, P. T.

    2016-04-01

    The Transient High Energy Sky and Early Universe Surveyor is a mission which will be proposed for the ESA M5 call. THESEUS will address multiple components in the Early Universe ESA Cosmic Vision theme:4.1 Early Universe,4.2 The Universe taking shape, and4.3 The evolving violent Universe.THESEUS aims at vastly increasing the discovery space of the high energy transient phenomena over the entire cosmic history. This is achieved via a unique payload providing an unprecedented combination of: (i) wide and deep sky monitoring in a broad energy band(0.3 keV-20 MeV; (ii) focusing capabilities in the soft X-ray band granting large grasp and high angular resolution; and (iii) on board near-IR capabilities for immediate transient identification and first redshift estimate.The THESEUS payload consists of: (i) the Soft X--ray Imager (SXI), a set of Lobster Eye (0.3--6 keV) telescopes with CCD detectors covering a total FOV of 1 sr; (ii) the X--Gamma-rays spectrometer (XGS), a non-imaging spectrometer (XGS) based on SDD+CsI, covering the same FOV than the Lobster telescope extending the THESEUS energy band up to 20 MeV; and (iii) a 70cm class InfraRed Telescope (IRT) observing up to 2 microns with imaging and moderate spectral capabilities.The main scientific goals of THESEUS are to:(a) Explore the Early Universe (cosmic dawn and reionization era) by unveiling the Gamma--Ray Burst (GRBs) population in the first billion years}, determining when did the first stars form, and investigating the re-ionization epoch, the interstellar medium (ISM) and the intergalactic medium (IGM) at high redshifts.(b) Perform an unprecedented deep survey of the soft X-ray transient Universe in order to fill the present gap in the discovery space of new classes of transient; provide a fundamental step forward in the comprehension of the physics of various classes of Galactic and extra--Galactic transients, and provide real time trigger and accurate locations of transients for follow-up with next

  19. Improvement of job satisfaction and organisational commitment through work group identification: an examination of the quantity surveyors in Hong Kong

    Directory of Open Access Journals (Sweden)

    Wai Yee Betty Chiu

    2013-09-01

    Full Text Available Though extant literatures in other sectors indicatethat job satisfaction and organizational commitment are important fordetermining individual and organisational outcomes, limited related researchhas been conducted amongst quantity surveyors in Hong Kong. Given cooperativeworking arrangement in the quantity surveying profession, work groupidentification is regarded as an important antecedent for determining jobsatisfaction and organisational commitment. The aim of this study is to examinewhether work group identification improves job satisfaction and organisationalcommitment. A questionnaire survey is conducted to collect data from quantitysurveyors working in private sector. A total of 71 valid responses are obtainedfrom 509 contacted quantity surveyors in Hong Kong. Bivariate correlation andmultiple regression analyses are performed to find the significance ofrelationships among the variables. Data analysis results support mosthypotheses. Work group identification is found to have significant positiveeffect on job satisfaction, affective and normative commitment. The finding isa bold step for quantity surveying companies to improve their quantity surveyors’job satisfaction and commitment level. The role of other contextual and organisationalfactors on job satisfaction and organisational commitment needs to becomplemented for future research.

  20. Cloud amount/frequency, NITRATE and other data from SURVEYOR in the Chukchi Sea from 1990-10-02 to 1990-10-20 (NODC Accession 9200012)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Conductivity, Temperature and Depth (CTD) and other data were collected in Chukchi Sea. Data was collected during 155 Casts from Ship SURVEYOR. The data was...

  1. Wave phenomena comparison between Mars and Titan upper atmospheres

    Science.gov (United States)

    Elrod, Meredith K.; Bell, J. M.

    2013-10-01

    We will examine the presence of waves in the neutral atmospheres of two terrestrial bodies: Mars and Titan. We will examine the aerobraking datasets from both the Mars Global Surveyor (MGS) and Mars Odyssey (ODY) missions, analyzing the neutral densities to characterize the planetary tides and/or smaller-scale internal gravity waves present in the data. While several studies have examined these features before at Mars (e.g., Forbes et al. [2002] and Fritts and Tolson [2006]), we will be focusing on examining whether or not the wave features observed in the thermosphere could be explained primarily with planetary tides, as posted recently in Klienbohl et al. [2013]. In addition to this, we will also examine the neutral densities obtained by the Cassini Ion-Neutral Mass Spectrometer (INMS) in order to determine if planetary tides can explain the numerous wave-like features that have been interpreted as gravity waves propagating vertically (cf., Mueller-Wodarg et al. [2008], Cui et al. [2013], and Snowden et al. [2013]).

  2. Tracking Boulders

    Science.gov (United States)

    2006-01-01

    13 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a trough in the Sirenum Fossae region. On the floor and walls of the trough, large -- truck- to house-sized -- boulders are observed at rest. However, there is evidence in this image for the potential for mobility. In the central portion of the south (bottom) wall, a faint line of depressions extends from near the middle of the wall, down to the rippled trough floor, ending very near one of the many boulders in the area. This line of depressions is a boulder track; it indicates the path followed by the boulder as it trundled downslope and eventually came to rest on the trough floor. Because it is on Mars, even when the boulder is sitting still, this once-rolling stone gathers no moss. Location near: 29.4oS, 146.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  3. Extratropical Weather Systems on Mars: Radiatively-Active Water Ice Effects

    Science.gov (United States)

    Hollingsworth, J. L.; Kahre, M. A.; Haberle, R. M.; Urata, R. A.; Montmessin, F.

    2017-01-01

    Extratropical, large-scale weather disturbances, namely transient, synoptic-period,baroclinic barotropic eddies - or - low- (high-) pressure cyclones (anticyclones), are components fundamental to global circulation patterns for rapidly rotating, differentially heated, shallow atmospheres such as Earth and Mars. Such "wave-like" disturbances that arise via (geophysical) fluid shear instability develop, mature and decay, and travel west-to-east in the middle and high latitudes within terrestrial-like planetary atmospheres. These disturbances serve as critical agents in the transport of heat and momentum between low and high latitudes of the planet. Moreover, they transport trace species within the atmosphere (e.g., water vapor/ice, other aerosols (dust), chemical species, etc). Between early autumn through early spring, middle and high latitudes on Mars exhibit strong equator-to-pole mean temperature contrasts (i.e., "baroclinicity"). Data collected during the Viking era and observations from both the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) indicate that such strong baroclinicity supports vigorous, large-scale eastward traveling weather systems [Banfield et al., 2004; Barnes et al., 1993]. A good example of traveling weather systems, frontal wave activity and sequestered dust activity from MGS/MOC image analyses is provided in Figure 1 (cf. Wang et al. [2005]). Utilizing an upgraded and evolving version of the NASA Ames Research Center (ARC) Mars global climate model, investigated here are key dynamical and physical aspects of simulated northern hemisphere (NH) large-scale extratropica lweather systems,with and without radiatively-active water ice clouds. Mars Climate Model:

  4. The Transient High Energy Sky and Early Universe Surveyor (THESEUS)

    Science.gov (United States)

    Amati, Lorenzo; O'Brien, Paul T.; Götz, Diego

    2016-07-01

    The Transient High Energy Sky and Early Universe Surveyor (THESEUS) is a mission concept under development by a large international collaboration aimed at exploiting gamma-ray bursts for investigating the early Universe. The main scientific objectives of THESEUS include: investigating the star formation rate and metallicity evolution of the ISM and IGM up to redshift 9-10, detecting the first generation (pop III) of stars, studying the sources and physics of re-ionization, detecting the faint end of galaxies luminosity function. These goals will be achieved through a unique combination of instruments allowing GRB detection and arcmin localization over a broad FOV (more than 1sr) and an energy band extending from several MeVs down to 0.3 keV with unprecedented sensitivity, as well as on-board prompt (few minutes) follow-up with a 0.6m class IR telescope with both imaging and spectroscopic capabilities. Such instrumentation will also allow THESEUS to unveil and study the population of soft and sub-energetic GRBs, and, more in general, to perform monitoring and survey of the X-ray sky with unprecedented sensitivity.

  5. Assessment of Viability Appraisal Practice by Estate Surveyors and Valuers in Lagos Metropolis, Nigeria

    Directory of Open Access Journals (Sweden)

    Oyetunji Abiodun Kolawale

    2017-01-01

    Full Text Available A capital investment appraisal is a means of ensuring value for money. It is not meant to provide an indication of profit or loss, but rather a comparison of costs in relation to those areas where there is an opportunity or an inclination for change. The decision to invest in a project is based on the expectation of future returns since a rational investor does not expect to incur loss on his capital outlay. This decision making is usually hinged on advice obtained during pre-investment appraisal. This study is aimed at evaluating the mode of practicing investment viability appraisal by Estate Surveyors and Valuers in Lagos metropolis. The data for the study was obtained by randomly administering structured questionnaires on eighty-seven (87 practicing Estate Surveyors and Valuers in the study area and the findings were analyzed through descriptive statistical tools such as the Likert scale to present the result. Findings revealed that the payback period is the most adopted appraisal technique in practice as evidenced with a mean score of 3.57. The objective (s of the investor is also the most significant factor being considered while selecting appraisal technique with a mean score of 3.83 while the problems of actual return varying from the expected return and also difficulty in the repayment of loans always result when a wrong viability technique is employed. The success of any viability study goes beyond knowing the objective (s of the investor; therefore, it was recommended that appraisers should ensure that they are equipped with adequate knowledge required for the execution of feasibility and on viability studies because knowing the right viability criteria for a particular objective will help in advising an investor on a course of action that will best achieve the developer’s objective.

  6. Optimal Management Of Renewable-Based Mgs An Intelligent Approach Through The Evolutionary Algorithm

    Directory of Open Access Journals (Sweden)

    Mehdi Nafar

    2015-08-01

    Full Text Available Abstract- This article proposes a probabilistic frame built on Scenario fabrication to considerate the uncertainties in the finest action managing of Micro Grids MGs. The MG contains different recoverable energy resources such as Wind Turbine WT Micro Turbine MT Photovoltaic PV Fuel Cell FC and one battery as the storing device. The advised frame is based on scenario generation and Roulette wheel mechanism to produce different circumstances for handling the uncertainties of altered factors. It habits typical spreading role as a probability scattering function of random factors. The uncertainties which are measured in this paper are grid bid alterations cargo request calculating error and PV and WT yield power productions. It is well-intentioned to asset that solving the MG difficult for 24 hours of a day by considering diverse uncertainties and different constraints needs one powerful optimization method that can converge fast when it doesnt fall in local optimal topic. Simultaneously single Group Search Optimization GSO system is presented to vision the total search space globally. The GSO algorithm is instigated from group active of beasts. Also the GSO procedure one change is similarly planned for this algorithm. The planned context and way is applied o one test grid-connected MG as a typical grid.

  7. Age of the Mars Global Northerly Slope: Evidence From Utopia Planitia

    Science.gov (United States)

    McGill, George E.

    2002-01-01

    Recent results from the Mars Orbiter Laser Altimeter (MOLA) experiment on Mars Global Surveyor (MGS) indicate that most of Mars is characterized by a very gentle, roughly northerly slope. Detailed mapping in north-central Arabia Terra combined with superposition relations and crater counts indicate that, in that region at least, this northerly slope must have been formed no later than Late Hesperian, with the most likely time of formation being Late Hesperian. Current research in Utopia Planitia intended as a test of extant models for the formation of giant polygons has turned up good evidence for a Late Hesperian age for the northerly tilt in this region as well, as will be discussed.

  8. Dunes with Frost

    Science.gov (United States)

    2004-01-01

    31 May 2004 Springtime for the martian northern hemisphere brings defrosting spots and patterns to the north polar dune fields. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example located near 76.7oN, 250.4oW. In summer, these dunes would be darker than their surroundings. However, while they are still covered by frost, they are not any darker than the substrate across which the sand is slowly traveling. Dune movement in this case is dominated by winds that blow from the southwest (lower left) toward the northeast (upper right). The picure covers an area about 3 km (1.9 mi) across and is illuminated by sunlight from the lower left.

  9. High Latitude Polygons

    Science.gov (United States)

    2005-01-01

    26 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows polygonal patterned ground on a south high-latitude plain. The outlines of the polygons, like the craters and hills in this region, are somewhat enhanced by the presence of bright frost left over from the previous winter. On Earth, polygons at high latitudes would usually be attributed to the seasonal freezing and thawing cycles of ground ice. The origin of similar polygons on Mars is less certain, but might also be an indicator of ground ice. Location near: 75.3oS, 113.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  10. The Cosmology Large Angular Scale Surveyor (CLASS): 40 GHz Optical Design

    Science.gov (United States)

    Eimer, Joseph R.; Bennett, Charles L.; Chuss, David T.; Marriage, Tobias; Wollack, Edward J.; Zeng, Lingzhen

    2012-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) instrument will measure the polarization of the cosmic microwave background at 40, 90, and 150 GHz from Cerro Toco in the Atacama desert of northern Chile. In this paper, we describe the optical design of the 40 GHz telescope system. The telescope is a diffraction limited catadioptric design consisting of a front-end Variable-delay Polarization Modulator (VPM), two ambient temperature mirrors, two cryogenic dielectric lenses, thermal blocking filters, and an array of 36 smooth-wall scalar feedhorn antennas. The feed horns guide the signal to antenna-coupled transition-edge sensor (TES) bolometers. Polarization diplexing and bandpass definition are handled on the same microchip as the TES. The feed horn beams are truncated with 10 dB edge taper by a 4 K Lyot-stop to limit detector loading from stray light and control the edge illumination of the front-end VPM. The field-of-view is 19 deg x 14 deg with a resolution for each beam on the sky of 1.5 deg. FWHM.

  11. The cosmology large angular scale surveyor (CLASS): 40 GHz optical design

    Science.gov (United States)

    Eimer, Joseph R.; Bennett, Charles L.; Chuss, David T.; Marriage, Tobias; Wollack, Edward J.; Zeng, Lingzhen

    2012-09-01

    The Cosmology Large Angular Scale Surveyor (CLASS) instrument will measure the polarization of the cosmic microwave background at 40, 90, and 150 GHz from Cerro Toco in the Atacama desert of northern Chile. In this paper, we describe the optical design of the 40 GHz telescope system. The telescope is a diffraction limited catadioptric design consisting of a front-end Variable-delay Polarization Modulator (VPM), two ambient temperature mirrors, two cryogenic dielectric lenses, thermal blocking filters, and an array of 36 smooth-wall scalar feedhorn antennas. The feed horns guide the signal to antenna-coupled transition-edge sensor (TES) bolometers. Polarization diplexing and bandpass definition are handled on the same microchip as the TES. The feed horn beams are truncated with 10 dB edge taper by a 4 K Lyot-stop to limit detector loading from stray light and control the edge illumination of the front-end VPM. The field-of-view is 19° x 14° with a resolution for each beam on the sky of 1.5° FWHM.

  12. "Long life" DC brush motor for use on the Mars surveyor program

    Science.gov (United States)

    Braun, David; Noon, Don

    1998-01-01

    DC brush motors have several qualities which make them very attractive for space flight applications. Their mechanical commutation is simple and lightweight, requiring no external sensing and control in order to function properly. They are extremely efficient in converting electrical energy into mechanical energy. Efficiencies over 80% are not uncommon, resulting in high power throughput to weight ratios. However, the inherent unreliability and short life of sliding electrical contacts, especially in vacuum, have driven previous programs to utilize complex brushless DC or the less efficient stepper motors. The Mars Surveyor Program (MSP'98) and the Shuttle Radar Topography Mission (SRTM) have developed a reliable "long life" brush type DC motor for operation in low temperature, low pressure CO2 and N2, utilizing silver-graphite brushes. The original intent was to utilize this same motor for SRTM's space operation, but the results thus far have been unsatisfactory in vacuum. This paper describes the design, test, and results of this development.

  13. Chryse 'Alien Head'

    Science.gov (United States)

    2005-01-01

    26 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater in Chryse Planitia, not too far from the Viking 1 lander site, that to seems to resemble a bug-eyed head. The two odd depressions at the north end of the crater (the 'eyes') may have formed by wind or water erosion. This region has been modified by both processes, with water action occurring in the distant past via floods that poured across western Chryse Planitia from Maja Valles, and wind action common occurrence in more recent history. This crater is located near 22.5oN, 47.9oW. The 150 meter scale bar is about 164 yards long. Sunlight illuminates the scene from the left/lower left.

  14. Frosty Polygons

    Science.gov (United States)

    2004-01-01

    16 January 2004 Looking somewhat like a roadmap, this 3 km (1.9 mi) wide view of a cratered plain in the martian south polar region shows a plethora of cracks that form polygonal patterns. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image is located near 78.9oS, 357.3oW. Polygons such as these, where they are found on Earth, would be indicators of the presence of subsurface ice. Whether the same is true for Mars is uncertain. What is certain is that modern, seasonal frost on the surface enhances the appearance of the polygons as the frost persists longer in the cracks than on adjacent plains. This southern springtime image is illuminated by sunlight from the upper left.

  15. The Transient High-Energy Sky and Early Universe Surveyor (THESEUS)

    Science.gov (United States)

    Amati, L.; O'Brien, P.; Goetz, D.; Tenzer, C.; Bozzo, E.

    2017-10-01

    The Transient High Energy Sky and Early Universe Surveyor (THESEUS) is a mission concept developed by a large international collaboration aimed at exploiting Gamma-Ray Bursts for investigating the early Universe. The main scientic objectives of THESEUS, currently under evaluation by ESA within the selection process for next M5 mission, include: investigating the star formation rate and metallicity evolution of the ISM and IGM up to redshift 10, detecting the first generation (pop III) of stars, studying the sources and physics of re-ionization, detecting the faint end of galaxies luminosity function. These goals will be achieved through a unique combination of instruments allowing GRB detection and arcmin localization over a broad FOV (more than 1sr) and an energy band extending from several MeVs down to 0.3 keV with unprecedented sensitivity, as well as on-board prompt (few minutes) follow-up with a 0.7m class IR telescope with both imaging and spectroscopic capabilities. Such instrumentation will also allow THESEUS to perform a monitoring of the X-ray sky with unprecedented sensitivity, which will provide a perfect service and sinergy to next generation multi-wavalength (e.g., E-ELT, SKA, CTA, ATHENA) and multi-messenger (aLIGO, aVIRGO, eLISA, ET, neutrino detectors, ...) facilities.

  16. The Size of Mars' Fluid Core From Mars k2 Love Number Obtained From Analysis of MGS Doppler Tracking.

    Science.gov (United States)

    Yoder, C. F.; Konopliv, A. S.; Yuan, D. N.; Standish, E. M.; Folkner, W. M.

    2002-12-01

    The solar tidal deformation of Mars, measured by its k2 potential Love number, has been obtained from analysis of MGS radio tracking. The observed k2 =0.164+-0.016 is large enough to rule out a solid iron core. The inferred core radius Rc (1600kmobserved J3, J5 amplitudes are consistent with estimates of ice cap mass only if the cap thickness increases with latitude and the south cap is significantly larger than the north cap.

  17. Expression profiles of two small heat shock proteins and antioxidant enzyme activity in Mytilus galloprovincialis exposed to cadmium at environmentally relevant concentrations

    Science.gov (United States)

    You, Liping; Ning, Xuanxuan; Chen, Leilei; Zhang, Linbao; Zhao, Jianmin; Liu, Xiaoli; Wu, Huifeng

    2014-03-01

    Small heat shock proteins encompass a widespread but diverse class of proteins, which play key roles in protecting organisms from various stressors. In the present study, the full-length cDNAs of two small heat shock proteins (MgsHSP22 and MgsHSP24.1) were cloned from Mytilus galloprovincialis, which encoded peptides of 181 and 247 amino acids, respectively. Both MgsHSP22 and MgsHSP24.1 were detected in all tissues examined by real-time PCR, with the highest expression being observed in muscle and gonad tissues. The real-time PCR results revealed that Cd significantly inhibited MgsHSP22 expression at 24 h and MgsHSP24.1 at 24 and 48 h under 5 μg/L Cd 2+ exposure. MgsHSP24.1 expression was also significantly inhibited after 50 μg/L Cd2+ exposure for 48 h. With regard to antioxidant enzymes, increased GPx and CAT activity were detected under Cd2+ stress (5 and 50 μg/L), while no significant difference in SOD activity was observed throughout the experiment. Overall, both MgsHsps and antioxidant enzymes revealed their potential as Cd stress biomarkers in M. galloprovincialis.

  18. Mars Orbiter Camera Views the 'Face on Mars' - Best View from Viking

    Science.gov (United States)

    1998-01-01

    Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.This Viking Orbiter image is one of the best Viking pictures of the area Cydonia where the 'Face' is located. Marked on the image are the 'footprint' of the high resolution (narrow angle) Mars Orbiter Camera image and the area seen in enlarged views (dashed box). See PIA01440-1442 for these images in raw and processed form.Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  19. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the SOUTHERN SURVEYOR in the Bass Strait, Coral Sea and others from 2008011 to 2010-10-31 (NODC Accession 0115181)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115181 includes chemical, meteorological, physical and underway - surface data collected from SOUTHERN SURVEYOR in the Bass Strait, Coral Sea, Great...

  20. Turbidity, SOLAR RADIATION - ATMOSPHERIC and other data from SURVEYOR in the North Pacific Ocean, Bering Sea and NE Pacific from 1995-09-10 to 1995-09-19 (NODC Accession 9600139)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrophysical, hydrochemical, and other data were collected from the SURVEYOR from September 10, 1995 to September 19, 1995. Data were submitted by Mr. David Kachel...

  1. A New Era in Geodesy and Cartography: Implications for Landing Site Operations

    Science.gov (United States)

    Duxbury, T. C.

    2001-01-01

    The Mars Global Surveyor (MGS) Mars Orbiter Laser Altimeter (MOLA) global dataset has ushered in a new era for Mars local and global geodesy and cartography. These data include the global digital terrain model (Digital Terrain Model (DTM) radii), the global digital elevation model (Digital Elevation Model (DEM) elevation with respect to the geoid), and the higher spatial resolution individual MOLA ground tracks. Currently there are about 500,000,000 MOLA points and this number continues to grow as MOLA continues successful operations in orbit about Mars, the combined processing of radiometric X-band Doppler and ranging tracking of MGS together with millions of MOLA orbital crossover points has produced global geodetic and cartographic control having a spatial (latitude/longitude) accuracy of a few meters and a topographic accuracy of less than 1 meter. This means that the position of an individual MOLA point with respect to the center-of-mass of Mars is know to an absolute accuracy of a few meters. The positional accuracy of this point in inertial space over time is controlled by the spin rate uncertainty of Mars which is less than 1 km over 10 years that will be improved significantly with the next landed mission.

  2. Vertical distribution of Martian aerosols from SPICAM/Mars-Express limb observations

    Science.gov (United States)

    Fedorova, A.; Korablev, O.; Bertaux, J.-L.; Rodin, A.; Perrier, S.; Moroz, V. I.

    Limb spectroscopic observations provide invaluable information about vertical distribution of main atmospheric components in the Martian atmosphere, in particular vertical distribution and structure of aerosols, which play an important role in the heat balance of the planet. Only limited set of successful limb spectroscopic observations have been carried out on Mars so far, including those by MGS/TES spectrometer and Thermoscan and Auguste experiments of Phobos mission. Currently SPICAM instrument onboard Mars-Express spacecraft has accomplished several sequences of limb observations. First analysis of limb sounding data received by SPICAM IR and UV channels, which imply the presence of fine, deep, optically thin aerosol fraction extended over broad range of altitudes, is presented.

  3. CTD data from CTD casts in the Northeast Pacific Ocean from NOAA Ship DISCOVERER and NOAA Ship SURVEYOR from 1985-06-03 to 1988-09-21 (NODC Accession 8900194)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CTD data were collected from CTD casts from NOAA Ship DISCOVERER and NOAA Ship SURVEYOR in the Northeast Pacific Ocean from 03 June 1985 to 21 September 1988. Data...

  4. The Aerial Regional-Scale Environmental Surveyor (ARES): New Mars Science to Reduce Human Risk and Prepare for the Human Exploration

    Science.gov (United States)

    Levine, Joel S.; Croom, Mark A.; Wright, Henry S.; Killough, B. D.; Edwards, W. C.

    2012-01-01

    Obtaining critical measurements for eventual human Mars missions while expanding upon recent Mars scientific discoveries and deriving new scientific knowledge from a unique near surface vantage point is the focus of the Aerial Regional-scale Environmental Surveyor (ARES) exploration mission. The key element of ARES is an instrumented,rocket-powered, well-tested robotic airplane platform, that will fly between one to two kilometers above the surface while traversing hundreds of kilometers to collect and transmit previously unobtainable high spatial measurements relevant to the NASA Mars Exploration Program and the exploration of Mars by humans.

  5. Ripple Trap

    Science.gov (United States)

    2006-01-01

    3 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples. Conversely, the lava flow apparently acted as a trap for windblown materials, illustrated by the presence of the light-toned, wave-like texture over much of the flow. That the lava flow surface trapped windblown sand and granules better than the cratered plain indicates that the flow surface has a rougher texture at a scale too small to resolve in this image. Location near: 10.7oN, 204.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  6. Temperature, salinity and other measurements found in dataset CTD taken from the SOUTHERN SURVEYOR (VLHJ) in the Coastal S Pacific, Equatorial Pacific and other locations from 2003 to 2006 (NODC Accession 0043461)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature, salinity, chemical, and other data were collected using CTD casts from the SOUTHERN SURVEYOR in the Iceland Sea and North / South Pacific Ocean. Data...

  7. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the SOUTHERN SURVEYOR in the Coral Sea, Great Australian Bight and others from 2011-04-06 to 2011-11-26 (NODC Accession 0115708)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115708 includes chemical, meteorological, physical and underway - surface data collected from SOUTHERN SURVEYOR in the Coral Sea, Great Australian...

  8. Drivers militating against the pricing of sustainable construction materials: The Ghanaian quantity surveyors perspective

    Directory of Open Access Journals (Sweden)

    Ernest Kissi

    2018-06-01

    Full Text Available Sustainability has in recent times attained much acceptance as a result of its positive impact on the environment, social and economic issues. Nevertheless, in developing countries, the price of sustainable construction materials are too high. The aim of the study was to examine drivers militating against the pricing of sustainable construction materials. Through an in-depth review of literature as well as an interview survey, questionnaire was designed and administered to practicing quantity surveyors. Data generated from the survey was analysed using Principal Component Analysis which resulted four main drivers. These included: awareness challenge (AC, sustainability measurement tools challenge (SMTC, economic challenge (EC, and information challenge (IC. The study offers useful lessons on sustainable practices that pricing experts in the construction industry can draw on when pricing.The need for this study cannot be doubted since the consciousness of such challenges will help in resolving issues associated with pricing of sustainable construction materials. Keywords: Drivers, Militating, Pricing, Sustainable construction materials, Ghanaian

  9. The Large UV/Optical/Infrared Surveyor (LUVOIR): Decadal Mission concept technology development overview

    Science.gov (United States)

    Bolcar, Matthew R.

    2017-09-01

    The Large Ultraviolet / Optical / Infrared (LUVOIR) Surveyor is one of four large mission concept studies being developed by NASA for consideration in the 2020 Astrophysics Decadal Survey. LUVOIR will support a broad range of science objectives, including the direct imaging and spectral characterization of habitable exoplanets around sun-like stars, the study of galaxy formation and evolution, the epoch of reionization, star and planet formation, and the remote sensing of Solar System bodies. The LUVOIR Science and Technology Definition Team (STDT) has tasked a Technology Working Group (TWG), with more than 60 members from NASA centers, academia, industry, and international partners, with identifying technologies that enable or enhance the LUVOIR science mission. The TWG has identified such technologies in the areas of Coronagraphy, Ultra-Stable Opto-mechanical Systems, Detectors, Coatings, Starshades, and Instrument Components, and has completed a detailed assessment of the state-of-the-art. We present here a summary of this technology assessment effort, as well as the current progress in defining a technology development plan to mature these technologies to the required technology readiness level (TRL).

  10. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the SOUTHERN SURVEYOR in the Coral Sea, Indian Ocean and others from 2012-04-11 to 2012-07-25 (NODC Accession 0115295)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115295 includes chemical, meteorological, physical and underway - surface data collected from SOUTHERN SURVEYOR in the Coral Sea, Indian Ocean, South...

  11. Oxidation feature and diffusion mechanism of Zr-based metallic glasses near the glass transition point

    Science.gov (United States)

    Hu, Zheng; Lei, Xianqi; Wang, Yang; Zhang, Kun

    2018-03-01

    The oxidation behaviors of as-cast, pre-deformed, and crystallized Zr47.9Ti0.3Ni3.1Cu39.3Al9.4 metallic glasses (MGs) were studied near the glass transition point. The oxidation kinetics of the crystallized MGs followed a parabolic-rate law, and the as-cast and pre-deformed MGs exerted a typical two-stage behavior above the glass transition temperature (T g). Most interesting, pre-deformed treatment can significantly improve the oxidation rate of MGs, as the initial oxidation appeared earlier than for the as-cast MGs, and was accompanied by much thicker oxide scale. The EDS and XPS results showed that the metal Al acted as the preferred scavenger that absorbed intrinsic oxygen in the near-surface region of as-cast MGs. However, a homogeneous mixed layer without Al was observed in the pre-deformed MGs. We speculated the accelerated diffusion of other elements in the MGs was due to the local increase in the free volume and significant shear-induced dilation of the local structure. The results from this study demonstrate that MGs exhibit controllable atomic diffusion during the oxidation process, which can facilitate use in super-cooled liquid region applications.

  12. In Situ Atmospheric Pressure Measurements in the Martian Southern Polar Region: Mars Volatiles and Climate Surveyor Meteorology Package on the Mars Polar Lander

    Science.gov (United States)

    Harri, A.-M.; Polkko, J.; Siili, T.; Crisp, D.

    1998-01-01

    Pressure observations are crucial for the success of the Mars Volatiles and Climate Surveyor (MVACS) Meteorology (MET) package onboard the Mars Polar Lander (MPL), due for launch early next year. The spacecraft is expected to land in December 1999 (L(sub s) = 256 degrees) at a high southern latitude (74 degrees - 78 degrees S). The nominal period of operation is 90 sols but may last up to 210 sols. The MVACS/MET experiment will provide the first in situ observations of atmospheric pressure, temperature, wind, and humidity in the southern hemisphere of Mars and in the polar regions. The martian atmosphere goes through a large-scale atmospheric pressure cycle due to the annual condensation/sublimation of the atmospheric CO2. Pressure also exhibits short period variations associated with dust storms, tides, and other atmospheric events. A series of pressure measurements can hence provide us with information on the large-scale state and dynamics of the atmosphere, including the CO2 and dust cycles as well as local weather phenomena. The measurements can also shed light on the shorter time scale phenomena (e.g., passage of dust devils) and hence be important in contributing to our understanding of mixing and transport of heat, dust, and water vapor.

  13. Pressure Balance at Mars and Solar Wind Interaction with the Martian Atmosphere

    Science.gov (United States)

    Krymskii, A. M.; Ness, N. F.; Crider, D. H.; Breus, T. K.; Acuna, M. H.; Hinson, D.

    2003-01-01

    The strongest crustal fields are located in certain regions in the Southern hemisphere. In the Northern hemisphere, the crustal fields are rather weak and usually do not prevent direct interaction between the SW and the Martian ionosphere/atmosphere. Exceptions occur in the isolated mini-magnetospheres formed by the crustal anomalies. Electron density profiles of the ionosphere of Mars derived from radio occultation data obtained by the Radio Science Mars Global Surveyor (MGS) experiment have been compared with the crustal magnetic fields measured by the MGS Magnetometer/Electron Reflectometer (MAG/ER) experiment. A study of 523 electron density profiles obtained at latitudes from +67 deg. to +77 deg. has been conducted. The effective scale-height of the electron density for two altitude ranges, 145-165 km and 165-185 km, and the effective scale-height of the neutral atmosphere density in the vicinity of the ionization peak have been derived for each of the profiles studied. For the regions outside of the potential mini-magnetospheres, the thermal pressure of the ionospheric plasma for the altitude range 145-185 km has been estimated. In the high latitude ionosphere at Mars, the total pressure at altitudes 160 and 180 km has been mapped. The solar wind interaction with the ionosphere of Mars and origin of the sharp drop of the electron density at the altitudes 200-210 km will be discussed.

  14. 4-Meter Gait Speed Test in Chronic Obstructive Pulmonary Disease: INTERRATER RELIABILITY USING A STOPWATCH.

    Science.gov (United States)

    Bisca, Gianna Waldrich; Fava, Lucas Rodrigues; Morita, Andrea Akemi; Machado, Felipe Vilaça Cavallari; Pitta, Fabio; Hernandes, Nidia Aparecida

    2017-12-14

    4-meter gait speed (4MGS) is increasingly used to assess functional performance in patients with chronic obstructive pulmonary disease. However, the current literature lacks information regarding some technical standards for this test. Therefore, the purpose of this study was to compare and to evaluate the interrater reliability between a stopwatch and video recording used as timing systems for the 4MGS in patients with chronic obstructive pulmonary disease, as well as to verify the interrater reliability between 2 observers measuring the 4MGS time using a manual stopwatch. Fifty-one patients performed the 4MGS using 4 different protocols (random order): walking at the usual and maximum speed in a 4-meter course and walking at the same 2 speeds on an 8-m course using a 2-m acceleration zone, a 4-meter timing area, and a 2-m deceleration zone. Gait speed was measured simultaneously using a stopwatch and a video recording. In a subanalysis (n = 24), 2 independent observers timed the 4MGS using a stopwatch. There was no significant difference in comparison between the 2 timing methods (P > .05 for all), and the reliability between video recording and stopwatch was excellent in all 4MGS studied protocols (intraclass correlation coefficient ≥ 0.91). Moreover, when comparing gait speed measured by 2 observers using a stopwatch, no significant difference was found among all proposed protocols (P > .05 for all), and there was also excellent reliability between the 2 independent observers (intraclass correlation coefficient ≥ 0.94). The stopwatch, a low-cost and feasible tool, is reliable as a timing device for the 4MGS in patients with chronic obstructive pulmonary disease.

  15. Plasticity of ductile metallic glasses: a self-organized critical state.

    Science.gov (United States)

    Sun, B A; Yu, H B; Jiao, W; Bai, H Y; Zhao, D Q; Wang, W H

    2010-07-16

    We report a close correlation between the dynamic behavior of serrated flow and the plasticity in metallic glasses (MGs) and show that the plastic deformation of ductile MGs can evolve into a self-organized critical state characterized by the power-law distribution of shear avalanches. A stick-slip model considering the interaction of multiple shear bands is presented to reveal complex scale-free intermittent shear-band motions in ductile MGs and quantitatively reproduce the experimental observations. Our studies have implications for understanding the precise plastic deformation mechanism of MGs.

  16. Magnetic Storms at Mars and Earth

    DEFF Research Database (Denmark)

    Vennerstrøm, Susanne; Falkenberg, Thea Vilstrup

    In analogy with magnetic storms at the Earth, periods of significantly enhanced global magnetic activity also exist at Mars. The extensive database of magnetic measurements from Mars Global Surveyor (MGS), covering almost an entire solar cycle, is used in combination with geomagnetic activity...... indices at Earth to compare the occurrence of magnetic storms at Mars and Earth. Based on superposed epochs analysis the time-development of typical magnetic storms at Mars and Earth is described. In contradiction to storms at Earth, most magnetic storms at Mars are found to be associated...... with heliospheric current sheet crossings, where the IMF changes polarity. While most storms at the Earth occur due to significant southward excursions of the IMF associated with CMEs, at Mars most storms seem to be associated with the density enhancement of the heliospheric current sheet. Density enhancements...

  17. Tharsis Limb Cloud

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Annotated image of Tharsis Limb Cloud 7 September 2005 This composite of red and blue Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired on 6 July 2005 shows an isolated water ice cloud extending more than 30 kilometers (more than 18 miles) above the martian surface. Clouds such as this are common in late spring over the terrain located southwest of the Arsia Mons volcano. Arsia Mons is the dark, oval feature near the limb, just to the left of the 'T' in the 'Tharsis Montes' label. The dark, nearly circular feature above the 'S' in 'Tharsis' is the volcano, Pavonis Mons, and the other dark circular feature, above and to the right of 's' in 'Montes,' is Ascraeus Mons. Illumination is from the left/lower left. Season: Northern Autumn/Southern Spring

  18. Accuracy of Single Frequency GPS Observations Processing In Near Real-time With Use of Code Predicted Products

    Science.gov (United States)

    Wielgosz, P. A.

    In this year, the system of active geodetic GPS permanent stations is going to be estab- lished in Poland. This system should provide GPS observations for a wide spectrum of users, especially it will be a great opportunity for surveyors. Many of surveyors still use cheaper, single frequency receivers. This paper focuses on processing of single frequency GPS observations only. During processing of such observations the iono- sphere plays an important role, so we concentrated on the influence of the ionosphere on the positional coordinates. Twenty consecutive days of GPS data from 2001 year were processed to analyze the accuracy of a derived three-dimensional relative vec- tor position between GPS stations. Observations from two Polish EPN/IGS stations: BOGO and JOZE were used. In addition to, a new test station - IGIK was created. In this paper, the results of single frequency GPS observations processing in near real- time are presented. Baselines of 15, 27 and 42 kilometers and sessions of 1, 2, 3, 4, and 6 hours long were processed. While processing we used CODE (Centre for Orbit De- termination in Europe, Bern, Switzerland) predicted products: orbits and ionosphere info. These products are available in real-time and enable near real-time processing. Software Bernese v. 4.2 for Linux and BPE (Bernese Processing Engine) mode were used. These results are shown with a reference to dual frequency weekly solution (the best solution). Obtained GPS positional time and GPS baseline length dependency accuracy is presented for single frequency GPS observations.

  19. Virtual Surveyor based Object Extraction from Airborne LiDAR data

    Science.gov (United States)

    Habib, Md. Ahsan

    Topographic feature detection of land cover from LiDAR data is important in various fields - city planning, disaster response and prevention, soil conservation, infrastructure or forestry. In recent years, feature classification, compliant with Object-Based Image Analysis (OBIA) methodology has been gaining traction in remote sensing and geographic information science (GIS). In OBIA, the LiDAR image is first divided into meaningful segments called object candidates. This results, in addition to spectral values, in a plethora of new information such as aggregated spectral pixel values, morphology, texture, context as well as topology. Traditional nonparametric segmentation methods rely on segmentations at different scales to produce a hierarchy of semantically significant objects. Properly tuned scale parameters are, therefore, imperative in these methods for successful subsequent classification. Recently, some progress has been made in the development of methods for tuning the parameters for automatic segmentation. However, researchers found that it is very difficult to automatically refine the tuning with respect to each object class present in the scene. Moreover, due to the relative complexity of real-world objects, the intra-class heterogeneity is very high, which leads to over-segmentation. Therefore, the method fails to deliver correctly many of the new segment features. In this dissertation, a new hierarchical 3D object segmentation algorithm called Automatic Virtual Surveyor based Object Extracted (AVSOE) is presented. AVSOE segments objects based on their distinct geometric concavity/convexity. This is achieved by strategically mapping the sloping surface, which connects the object to its background. Further analysis produces hierarchical decomposition of objects to its sub-objects at a single scale level. Extensive qualitative and qualitative results are presented to demonstrate the efficacy of this hierarchical segmentation approach.

  20. Inversion of Gravity and Magnetic Field Data for Tyrrhena Patera

    Science.gov (United States)

    Milbury, C.; Schubert, G.; Raymond, C. A.; Smrekar, S. E.

    2011-01-01

    Tyrrhena Patera is located to the southeast/northeast of the Isidis/Hellas impact basin. It was geologically active into the Late Amazonian, although the main edifice was formed in the Noachian(approximately 3.7-4.0 Ga). Tyrrhena Patera and the surrounding area contain gravity and magnetic anomalies that appear to be correlated. The results presented here are for the anomalies 1a and 1b (closest to Tyrrhena Patera), however other anomalies in this region have been modeled and will be presented at the conference.The Mars Global Surveyor (MGS) free-air gravity signature of Tyrrhena Patera has been studied by Kiefer, who inferred the existence of an extinct magma chamber below it. The magnetic signature has been mapped by Lillis R. J. et al., who compared electron reflectometer data, analogous to the total magnetic field, for Syrtis Major and Tyrrhena Patera and argued for demagnetization of both volcanoes.

  1. Atomistic origin of size effects in fatigue behavior of metallic glasses

    Science.gov (United States)

    Sha, Zhendong; Wong, Wei Hin; Pei, Qingxiang; Branicio, Paulo Sergio; Liu, Zishun; Wang, Tiejun; Guo, Tianfu; Gao, Huajian

    2017-07-01

    While many experiments and simulations on metallic glasses (MGs) have focused on their tensile ductility under monotonic loading, the fatigue mechanisms of MGs under cyclic loading still remain largely elusive. Here we perform molecular dynamics (MD) and finite element simulations of tension-compression fatigue tests in MGs to elucidate their fatigue mechanisms with focus on the sample size effect. Shear band (SB) thickening is found to be the inherent fatigue mechanism for nanoscale MGs. The difference in fatigue mechanisms between macroscopic and nanoscale MGs originates from whether the SB forms partially or fully through the cross-section of the specimen. Furthermore, a qualitative investigation of the sample size effect suggests that small sample size increases the fatigue life while large sample size promotes cyclic softening and necking. Our observations on the size-dependent fatigue behavior can be rationalized by the Gurson model and the concept of surface tension of the nanovoids. The present study sheds light on the fatigue mechanisms of MGs and can be useful in interpreting previous experimental results.

  2. The Large UV/Optical/Infrared Surveyor (LUVOIR): Decadal Mission concept design update

    Science.gov (United States)

    Bolcar, Matthew R.; Aloezos, Steve; Bly, Vincent T.; Collins, Christine; Crooke, Julie; Dressing, Courtney D.; Fantano, Lou; Feinberg, Lee D.; France, Kevin; Gochar, Gene; Gong, Qian; Hylan, Jason E.; Jones, Andrew; Linares, Irving; Postman, Marc; Pueyo, Laurent; Roberge, Aki; Sacks, Lia; Tompkins, Steven; West, Garrett

    2017-09-01

    In preparation for the 2020 Astrophysics Decadal Survey, NASA has commissioned the study of four large mission concepts, including the Large Ultraviolet / Optical / Infrared (LUVOIR) Surveyor. The LUVOIR Science and Technology Definition Team (STDT) has identified a broad range of science objectives including the direct imaging and spectral characterization of habitable exoplanets around sun-like stars, the study of galaxy formation and evolution, the epoch of reionization, star and planet formation, and the remote sensing of Solar System bodies. NASA's Goddard Space Flight Center (GSFC) is providing the design and engineering support to develop executable and feasible mission concepts that are capable of the identified science objectives. We present an update on the first of two architectures being studied: a 15- meter-diameter segmented-aperture telescope with a suite of serviceable instruments operating over a range of wavelengths between 100 nm to 2.5 μm. Four instruments are being developed for this architecture: an optical / near-infrared coronagraph capable of 10-10 contrast at inner working angles as small as 2 λ/D the LUVOIR UV Multi-object Spectrograph (LUMOS), which will provide low- and medium-resolution UV (100 - 400 nm) multi-object imaging spectroscopy in addition to far-UV imaging; the High Definition Imager (HDI), a high-resolution wide-field-of-view NUV-Optical-IR imager; and a UV spectro-polarimeter being contributed by Centre National d'Etudes Spatiales (CNES). A fifth instrument, a multi-resolution optical-NIR spectrograph, is planned as part of a second architecture to be studied in late 2017.

  3. Effects of a CME on Mars

    DEFF Research Database (Denmark)

    Falkenberg, Thea Vilstrup; Vennerstrøm, Susanne; Brain, D.

    this balances the solar wind pressure. As the dynamic pressure is severely increased during a CME, so is the magnetic pressure. A CME are also typically connected to a Solar Energetic Particle (SEP) event, causing large amounts of radiation. When the shock front of a CME arrives at Mars strong signals are seen......We investigate the effects of a Coronal Mass Ejection (CME) on Mars. The magnetic field in the magnetic pileup region on Mars is dominated by the dynamic pressure from the solar as increased dynamic pressure compresses the magnetic pileup region causing a larger magnetic pressure, until...... in both the magnetic field data and in the radiation data. Based on Mars Global Surveyor (MGS) Magnetometer (MAG) and Electron Reflectometer (ER) data we study the radiation and magnetic field variations on Mars during a CME event. We also compare the effects on Mars to the effects on Earth for the same...

  4. Fusing Mobile In Situ Observations and Satellite Remote Sensing of Chemical Release Emissions to Improve Disaster Response

    Directory of Open Access Journals (Sweden)

    Ira Leifer

    2016-09-01

    Full Text Available Chemical release disasters have serious consequences, disrupting ecosystems, society, and causing significant loss of life. Mitigating the destructive impacts relies on identification and mapping, monitoring, and trajectory forecasting. Improvements in sensor capabilities are enabling airborne and spacebased remote sensing to support response activities. Key applications are improving transport models in complex terrain and improved disaster response.Chemical release disasters have serious consequences, disrupting ecosystems, society, and causing significant loss of life. Mitigating the destructive impacts relies on identification and mapping, monitoring, and trajectory forecasting. Improvements in sensor capabilities are enabling airborne and space-based remote sensing to support response activities. Key applications are improving transport models in complex terrain and improved disaster response.Understanding urban atmospheric transport in the Los Angeles Basin, where topographic influences on transport patterns are significant, was improved by leveraging the Aliso Canyon leak as an atmospheric tracer. Plume characterization data was collected by the AutoMObile trace Gas (AMOG Surveyor, a commuter car modified for science. Mobile surface in situ CH4 and winds were measured by AMOG Surveyor under Santa Ana conditions to estimate an emission rate of 365±30% Gg yr-1. Vertical profiles were collected by AMOG Surveyor by leveraging local topography for vertical profiling to identify the planetary boundary layer at ~700 m. Topography significantly constrained plume dispersion by up to a factor of two. The observed plume trajectory was used to validate satellite aerosol optical depth-inferred atmospheric transport, which suggested the plume first was driven offshore, but then veered back towards land. Numerical long-range transport model predictions confirm this interpretation. This study demonstrated a novel application of satellite aerosol remote

  5. The Moving Group Targets of the Seeds High-Contrast Imaging Survey of Exoplanets and Disks: Results and Observations from the First Three Years

    Science.gov (United States)

    Brandt, Timothy D.; Kuzuhara, Masayuki; McElwain, Michael W.; Schlieder, Joshua E.; Wisniewski, John P.; Turner, Edwin L.; Carson, J.; Matsuo, T.; Biller, B.; Bonnefoy, M.; hide

    2014-01-01

    We present results from the first three years of observations of moving group (MG) targets in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of (is) approximately10(exp 5) at 1" and (is) approximately 10(exp 6) beyond 2" around 63 proposed members of nearby kinematic MGs. We review each of the kinematic associations to which our targets belong, concluding that five, beta Pictoris ((is) approximately 20 Myr), AB Doradus ((is) approximately 100 Myr), Columba ((is) approximately 30 Myr), Tucana-Horogium ((is) approximately 30 Myr), and TW Hydrae ((is) approximately 10 Myr), are sufficiently well-defined to constrain the ages of individual targets. Somewhat less than half of our targets are high-probability members of one of these MGs. For all of our targets, we combine proposed MG membership with other age indicators where available, including Ca ii HK emission, X-ray activity, and rotation period, to produce a posterior probability distribution of age. SEEDS observations discovered a substellar companion to one of our targets, kappa And, a late B star. We do not detect any other substellar companions, but do find seven new close binary systems, of which one still needs to be confirmed. A detailed analysis of the statistics of this sample, and of the companion mass constraints given our age probability distributions and exoplanet cooling models, will be presented in a forthcoming paper.

  6. A hybrid concept (segmented plus monolithic fused silica shells) for a high-throughput and high-angular resolution x-ray mission (Lynx/X-Ray Surveyor like)

    Science.gov (United States)

    Basso, Stefano; Civitani, Marta; Pareschi, Giovanni; Parodi, Giancarlo

    2017-09-01

    Lynx is a large area and high angular resolution X-ray mission being studied by NASA to be presented to the next Decadal Survey for the implementation in the next decade. It aims to realize an X-ray telescope with the effective area similar to Athena (2 m2 at 1 keV) but with the same angular resolution of Chandra and a much larger Field Of View (up 20 arcmin x 20 arcmin). The science of X-ray Surveyor requires a large-throughput mirror assembly with sub-arcsec angular resolution. These future X-ray mirrors have a set of requirements which, collectively, represents very substantial advances over any currently in operation or planned for missions other than X-ray Surveyor. Of particular importance is achieving low mass per unit collecting area, while maintaining Chandra like angular resolution. Among the possible solutions under study, the direct polishing of both thin monolithic pseudo-cylindrical shells and segments made of fused silica are being considered as viable solutions for the implementation of the mirrors. Fused silica has very good thermomechanical parameters (including a very low CTE), making the material particularly well suited for for the production of the Lynx mirrors. It should be noted that the use of close shells is also very attractive, since the operations for the integration of the shells will be greatly simplified and the area lost due to the vignetting from the interfacing structures minimized even if the management of such big (diameter of 3 m) and thin shells have to be demonstrated. In this paper we will discuss a possible basic layout for a full shell mirror and a hybrid concept (segmented plus monolithic shells made of fused silica) as a second solution, for the Lynx/XRS telescope, discussing preliminary results in terms of optical and mechanical performance.

  7. The remarkable vision of Robert Hooke (1635-1703): first observer of the microbial world.

    Science.gov (United States)

    Gest, Howard

    2005-01-01

    Robert Hooke played important roles in the early development of the Royal Society of London. As Curator of Experiments of the Society, he became a pioneering microscopist, prolific inventor, astronomer, geologist, architect, and an effective surveyor of the City of London following the Great Fire of 1666. Hooke's Micrographia (1665) revealed the microscopic structures of numerous biological and inorganic objects and became an important source of information for later studies. Aside from the body of detailed observations reported and depicted in Micrographia, the Preface is in itself an extraordinary document that exhibits Hooke's fertile mind, philosophical insights, and rare ability to look into the future.

  8. A fast dynamic mode in rare earth based glasses

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, L. Z.; Xue, R. J.; Zhu, Z. G.; Wang, W. H.; Bai, H. Y., E-mail: hybai@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Ngai, K. L. [Dipartimento di Fisica, Università di Pisa, Largo B. Pontecorvo 3, I-56127 Pisa (Italy)

    2016-05-28

    Metallic glasses (MGs) usually exhibit only slow β-relaxation peak, and the signature of the fast dynamic is challenging to be observed experimentally in MGs. We report a general and unusual fast dynamic mode in a series of rare earth based MGs manifested as a distinct fast β′-relaxation peak in addition to slow β-relaxation and α-relaxation peaks. We show that the activation energy of the fast β′-relaxation is about 12RT{sub g} and is equivalent to the activation of localized flow event. The coupling of these dynamic processes as well as their relationship with glass transition and structural heterogeneity is discussed.

  9. Remote Sensing of Mars: Detection of Impact Craters on the Mars Global Surveyor DTM by Integrating Edge- and Region-Based Algorithms

    Science.gov (United States)

    Athanassas, C. D.; Vaiopoulos, A.; Kolokoussis, P.; Argialas, D.

    2018-03-01

    This study integrates two different computer vision approaches, namely the circular Hough transform (CHT) and the determinant of Hessian (DoH), to detect automatically the largest number possible of craters of any size on the digital terrain model (DTM) generated by the Mars Global Surveyor mission. Specifically, application of the standard version of CHT to the DTM captured a great number of craters with diameter smaller than 50 km only, failing to capture larger craters. On the other hand, DoH was successful in detecting craters that were undetected by CHT, but its performance was deterred by the irregularity of the topographic surface encompassed: strongly undulated and inclined (trended) topographies hindered crater detection. When run on a de-trended DTM (and keeping the topology unaltered) DoH scored higher. Current results, although not optimal, encourage combined use of CHT and DoH for routine crater detection undertakings.

  10. AKTIVITAS URIKASE YANG DIHASILKAN DARI BERBAGAI SEL LACTOBACILLUS PLANTARUM DAN PARAMETER KINETIKANYA

    Directory of Open Access Journals (Sweden)

    Dyah Iswantini

    2009-12-01

    Full Text Available Uric acid concentration could be determined by spectrophotometry method. Uric acid was oxidized into allatonin in the presence of uricase and calculated by measuring the decrease of uric acid absorbance at 293 nm. These uricase were obtained from cells of Lactobacillus plantarum. L. plantarum K. Mar. E was isolated from passion fruit skin and L. plantarum Mgs. Psmb and Mgs. Bst from mangosteen. This research was conducted to observe the activity and kinetics of uricase from various cells of L. plantarum by spectrophotometric method. The plate assay method indicated that L. plantarum produced uricase, based on the clear zone about 0,2 mm on glucose yeast peptone medium contained 0,2% uric acid. The optimum condition of uricase activity from the three different sources occured in physiological condition. Uricase activity generated from cells of L. plantarum K. Mar. E, Mgs. Psmb, and Mgs. Bst were 0,1073; 0,0867; and 0,0842 U/mL, respectively. The kinetic parameters for uricase, determined with uric acid as the substrate. Vmax produced by L. plantarum K. Mar. E, Mgs. Psmb, and Mgs. Bst were 1,3635; 0,0316; and 0,0418 U/mL of bacterial culture, respectively and KM 0,1541; 0,0061; and 0,0054 mM, respectively. Uricase activity in various bacterial cells of L. plantarum was stable until the second day

  11. A three-dimensional vertically aligned functionalized multilayer graphene architecture: an approach for graphene-based thermal interfacial materials.

    Science.gov (United States)

    Liang, Qizhen; Yao, Xuxia; Wang, Wei; Liu, Yan; Wong, Ching Ping

    2011-03-22

    Thermally conductive functionalized multilayer graphene sheets (fMGs) are efficiently aligned in large-scale by a vacuum filtration method at room temperature, as evidenced by SEM images and polarized Raman spectroscopy. A remarkably strong anisotropy in properties of aligned fMGs is observed. High electrical (∼386 S cm(-1)) and thermal conductivity (∼112 W m(-1) K(-1) at 25 °C) and ultralow coefficient of thermal expansion (∼-0.71 ppm K(-1)) in the in-plane direction of A-fMGs are obtained without any reduction process. Aligned fMGs are vertically assembled between contacted silicon/silicon surfaces with pure indium as a metallic medium. Thus-constructed three-dimensional vertically aligned fMG thermal interfacial material (VA-fMG TIM) architecture has significantly higher equivalent thermal conductivity (75.5 W m(-1) K(-1)) and lower contact thermal resistance (5.1 mm2 K W(-1)), compared with their counterpart from A-fMGs that are recumbent between silicon surfaces. This finding provides a throughout approach for a graphene-based TIM assembly as well as knowledge of vertically aligned graphene architectures, which may not only facilitate graphene's application in current demanding thermal management but also promote its widespread applications in electrodes of energy storage devices, conductive polymeric composites, etc.

  12. Use of maternal information for QTL detection in a (granddaughter design

    Directory of Open Access Journals (Sweden)

    Boichard Didier

    2002-05-01

    Full Text Available Abstract In a (granddaughter design, maternal information is often neglected because the number of progeny per dam is limited. The number of dams per maternal grandsire (MGS, however, could be large enough to contribute to QTL detection. But dams and MGS usually are not genotyped, there are two recombination opportunities between the MGS and the progeny, and at a given location, only half the progeny receive a MGS chromosomal segment. A 3-step procedure was developed to estimate: (1 the marker phenotypes probabilities of the MGS; (2 the probability of each possible MGS haplotype; (3 the probabilities that the progeny receives either the first, or second MGS segment, or a maternal grandam segment. These probabilities were used for QTL detection in a linear model including the effects of sire, MGS, paternal QTL, MGS QTL and maternal grandam QTL. Including the grandam QTL effect makes it possible to detect QTL in the grandam population, even when MGS are not informative. The detection power, studied by simulation, was rather high, provided that MGS family size was greater than 50. Using maternal information in the French dairy cattle granddaughter design made it possible to detect 23 additional QTL genomewise significant.

  13. 'Inca City' is Part of a Circular Feature

    Science.gov (United States)

    2002-01-01

    MGS MOC Release No. MOC2-319, 8 August 2002 [figure removed for brevity, see original site] 'Inca City' is the informal name given by Mariner 9 scientists in 1972 to a set of intersecting, rectilinear ridges that are located among the layered materials of the south polar region of Mars. Their origin has never been understood; most investigators thought they might be sand dunes, either modern dunes or, more likely, dunes that were buried, hardened, then exhumed. Others considered them to be dikes formed by injection of molten rock (magma) or soft sediment into subsurface cracks that subsequently hardened and then were exposed at the surface by wind erosion. The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) has provided new information about the 'Inca City' ridges, though the camera's images still do not solve the mystery. The new information comes in the form of a MOC red wide angle context frame taken in mid-southern spring, shown above left and above right. The original Mariner 9 view of the ridges is seen at the center. The MOC image shows that the 'Inca City' ridges, located at 82oS, 67oW, are part of a larger circular structure that is about 86 km (53 mi) across. It is possible that this pattern reflects an origin related to an ancient, eroded meteor impact crater that was filled-in, buried, then partially exhumed. In this case, the ridges might be the remains of filled-in fractures in the bedrock into which the crater formed, or filled-in cracks within the material that filled the crater. Or both explanations could be wrong. While the new MOC image shows that 'Inca City' has a larger context as part of a circular form, it does not reveal the exact origin of these striking and unusual martian landforms.

  14. Whole genome sequencing as a tool for phylogenetic analysis of clinical strains of Mitis group streptococci

    DEFF Research Database (Denmark)

    Rasmusen, L. H.; Dargis, R.; Iversen, Katrine Højholt

    2016-01-01

    observed in single gene analyses. Species identification based on single gene analysis showed their limitations when more strains were included. In contrast, analyses incorporating more sequence data, like MLSA, SNPs and core-genome analyses, provided more distinct clustering. The core-genome tree showed......Identification of Mitis group streptococci (MGS) to the species level is challenging for routine microbiology laboratories. Correct identification is crucial for the diagnosis of infective endocarditis, identification of treatment failure, and/or infection relapse. Eighty MGS from Danish patients...

  15. Sulfates on Mars: TES Observations and Thermal Inertia Data

    Science.gov (United States)

    Cooper, C. D.; Mustard, J. F.

    2001-05-01

    The high resolution thermal emission spectra returned by the TES spectrometer on the MGS spacecraft have allowed the mapping of a variety of minerals and rock types by different sets of researchers. Recently, we have used a linear deconvolution approach to compare sulfate-palagonite soil mixtures created in the laboratory with Martian surface spectra. This approach showed that a number of areas on Mars have spectral properties that match those of sulfate-cemented soils (but neither loose powder mixtures of sulfates and soils nor sand-sized grains of disaggregated crusted soils). These features do not appear to be caused by atmospheric or instrumental effects and are thus believed to be related to surface composition and texture. The distribution and physical state of sulfate are important pieces of information for interpreting surface processes on Mars. A number of different mechanisms could have deposited sulfate in surface layers. Some of these include evaporation of standing bodies of water, aerosol deposition of volcanic gases, hydrothermal alteration from groundwater, and in situ interaction between the atmosphere and soil. The areas on Mars with cemented sulfate signatures are spread across a wide range of elevations and are generally large in spatial scale. Some of the areas are associated with volcanic regions, but many are in dark red plains that have previously been interpreted as duricrust deposits. Our current work compares the distribution of sulfate-cemented soils as mapped by the spectral deconvolution approach with thermal inertia maps produced from both Viking and MGS-TES. Duricrust regions, interpreted from intermediate thermal inertia values, are large regions thought to be sulfate-cemented soils similar to coherent, sulfate-rich materials seen at the Viking lander sites. Our observations of apparent regions of cemented sulfate are also large in spatial extent. This scale information is important for evaluating formation mechanisms for the

  16. A Multicenter Phase I/II Study of the BCNU Implant (Gliadel ® Wafer) for Japanese Patients with Malignant Gliomas

    Science.gov (United States)

    AOKI, Tomokazu; NISHIKAWA, Ryo; SUGIYAMA, Kazuhiko; NONOGUCHI, Naosuke; KAWABATA, Noriyuki; MISHIMA, Kazuhiko; ADACHI, Jun-ichi; KURISU, Kaoru; YAMASAKI, Fumiyuki; TOMINAGA, Teiji; KUMABE, Toshihiro; UEKI, Keisuke; HIGUCHI, Fumi; YAMAMOTO, Tetsuya; ISHIKAWA, Eiichi; TAKESHIMA, Hideo; YAMASHITA, Shinji; ARITA, Kazunori; HIRANO, Hirofumi; YAMADA, Shinobu; MATSUTANI, Masao

    2014-01-01

    Carmustine (BCNU) implants (Gliadel® Wafer, Eisai Inc., New Jersey, USA) for the treatment of malignant gliomas (MGs) were shown to enhance overall survival in comparison to placebo in controlled clinical trials in the United States and Europe. A prospective, multicenter phase I/II study involving Japanese patients with MGs was performed to evaluate the efficacy, safety, and pharmacokinetics of BCNU implants. The study enrolled 16 patients with newly diagnosed MGs and 8 patients with recurrent MGs. After the insertion of BCNU implants (8 sheets maximum, 61.6 mg BCNU) into the removal cavity, various chemotherapies (including temozolomide) and radiotherapies were applied. After placement, overall and progression-free survival rates and whole blood BCNU levels were evaluated. In patients with newly diagnosed MGs, the overall survival rates at 12 months and 24 months were 100.0% and 68.8%, and the progression-free survival rate at 12 months was 62.5%. In patients with recurrent MGs, the progression-free survival rate at 6 months was 37.5%. There were no grade 4 or higher adverse events noted due to BCNU implants, and grade 3 events were observed in 5 of 24 patients (20.8%). Whole blood BCNU levels reached a peak of 19.4 ng/mL approximately 3 hours after insertion, which was lower than 1/600 of the peak BCNU level recorded after intravenous injections. These levels decreased to less than the detection limit (2.00 ng/mL) after 24 hours. The results of this study involving Japanese patients are comparable to those of previous studies in the United States and Europe. PMID:24739422

  17. Direct observation of atomic-level nucleation and growth processes from an ultrathin metallic glass films

    Energy Technology Data Exchange (ETDEWEB)

    Huang, K. Q.; Cao, C. R.; Sun, Y. T.; Li, J.; Bai, H. Y.; Zheng, D. N., E-mail: l.gu@iphy.ac.cn, E-mail: dzheng@iphy.ac.cn, E-mail: whw@iphy.ac.cn; Wang, W. H., E-mail: l.gu@iphy.ac.cn, E-mail: dzheng@iphy.ac.cn, E-mail: whw@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Gu, L., E-mail: l.gu@iphy.ac.cn, E-mail: dzheng@iphy.ac.cn, E-mail: whw@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100190 (China)

    2016-01-07

    Till date, there have been no direct atomic-level experimental observations of the earliest stages of the nucleation and growth processes of nanocrystals formed by thermally induced crystallization in ultrathin metallic glasses (MGs). Here, we present a study of the crystallization process in atomically thin and highly stable MG films using double spherical aberration-corrected scanning transmission electron microscopy (Cs-TEM). Taking advantage of the stability of MG films with a slow crystallization process and the atomic-level high resolution of Cs-TEM, we observe the formation of the nucleus precursor of nanocrystals formed by atom aggregation followed by concomitant coalescence and stepwise evolution of the shape of the nanocrystals with a monodispersed and separated bimodal size distribution. Molecular dynamics simulation of the atomic motion in the glass film on a rigid amorphous substrate confirms the stepwise evolution processes of atom aggregation, cluster formation, cluster movement on the substrate, and cluster coalescence into larger crystalline particles. Our results might provide a better fundamental understanding of the nucleation and growth processes of nanocrystals in thin MG films.

  18. Meier-Gorlin syndrome: Report of an additional patient with congenital heart disease

    Directory of Open Access Journals (Sweden)

    Rabah M. Shawky

    2014-10-01

    Full Text Available We report a 7 year old female child with the classical triad of Meier-Gorlin syndrome (MGS, (microtia, absent patella and short stature. She had the characteristic facial features, with normal mentality and defective speech, skeletal abnormalities, conductive hearing loss, cystitis and normal growth hormone level. She suffered from recurrent chest infection during the first year of life which improved gradually with age. Although congenital heart is rarely observed in MGS, our patient had in addition fenestrated interatrial septal defect.

  19. Modeling, Stability Analysis and Active Stabilization of Multiple DC-Microgrids Clusters

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2014-01-01

    ), and more especially during interconnection with other MGs, creating dc MG clusters. This paper develops a small signal model for dc MGs from the control point of view, in order to study stability analysis and investigate effects of CPLs and line impedances between the MGs on stability of these systems....... This model can be also used to synthesis and study dynamics of control loops in dc MGs and also dc MG clusters. An active stabilization method is proposed to be implemented as a dc active power filter (APF) inside the MGs in order to not only increase damping of dc MGs at the presence of CPLs but also...... to improve their stability while connecting to the other MGs. Simulation results are provided to evaluate the developed models and demonstrate the effectiveness of proposed active stabilization technique....

  20. Overproduction of lactimidomycin by cross-overexpression of genes encoding Streptomyces antibiotic regulatory proteins.

    Science.gov (United States)

    Zhang, Bo; Yang, Dong; Yan, Yijun; Pan, Guohui; Xiang, Wensheng; Shen, Ben

    2016-03-01

    The glutarimide-containing polyketides represent a fascinating class of natural products that exhibit a multitude of biological activities. We have recently cloned and sequenced the biosynthetic gene clusters for three members of the glutarimide-containing polyketides-iso-migrastatin (iso-MGS) from Streptomyces platensis NRRL 18993, lactimidomycin (LTM) from Streptomyces amphibiosporus ATCC 53964, and cycloheximide (CHX) from Streptomyces sp. YIM56141. Comparative analysis of the three clusters identified mgsA and chxA, from the mgs and chx gene clusters, respectively, that were predicted to encode the PimR-like Streptomyces antibiotic regulatory proteins (SARPs) but failed to reveal any regulatory gene from the ltm gene cluster. Overexpression of mgsA or chxA in S. platensis NRRL 18993, Streptomyces sp. YIM56141 or SB11024, and a recombinant strain of Streptomyces coelicolor M145 carrying the intact mgs gene cluster has no significant effect on iso-MGS or CHX production, suggesting that MgsA or ChxA regulation may not be rate-limiting for iso-MGS and CHX production in these producers. In contrast, overexpression of mgsA or chxA in S. amphibiosporus ATCC 53964 resulted in a significant increase in LTM production, with LTM titer reaching 106 mg/L, which is five-fold higher than that of the wild-type strain. These results support MgsA and ChxA as members of the SARP family of positive regulators for the iso-MGS and CHX biosynthetic machinery and demonstrate the feasibility to improve glutarimide-containing polyketide production in Streptomyces strains by exploiting common regulators.

  1. Thermal inertia and surface heterogeneity on Mars

    Science.gov (United States)

    Putzig, Nathaniel E.

    Thermal inertia derived from temperature observations is critical for understanding surface geology and assessing potential landing sites on Mars. Derivation methods generally assume uniform surface properties for any given observation. Consequently, horizontal heterogeneity and near-surface layering may yield apparent thermal inertia that varies with time of day and season. To evaluate the effects of horizontal heterogeneity, I modeled the thermal behavior of surfaces containing idealized material mixtures (dust, sand, duricrust, and rocks) and differing slope facets. These surfaces exhibit diurnal and seasonal variability in apparent thermal inertia of several 100 tiu, 1 even for components with moderately contrasting thermal properties. To isolate surface effects on the derived thermal inertia of Mars, I mapped inter- annual and seasonal changes in albedo and atmospheric dust opacity, accounting for their effects in a modified derivation algorithm. Global analysis of three Mars years of MGS-TES 2 data reveals diurnal and seasonal variations of ~200 tiu in the mid-latitudes and 600 tiu or greater in the polar regions. Correlation of TES results and modeled apparent thermal inertia of heterogeneous surfaces indicates pervasive surface heterogeneity on Mars. At TES resolution, the near-surface thermal response is broadly dominated by layering and is consistent with the presence of duricrusts over fines in the mid-latitudes and dry soils over ground ice in the polar regions. Horizontal surface mixtures also play a role and may dominate at higher resolution. In general, thermal inertia obtained from single observations or annually averaged maps may misrepresent surface properties. In lieu of a robust heterogeneous- surface derivation technique, repeat coverage can be used together with forward-modeling results to constrain the near-surface heterogeneity of Mars. 1 tiu == J m -2 K -1 s - 2 Mars Global Surveyor Thermal Emission Spectrometer

  2. Improved Mars Upper Atmosphere Climatology

    Science.gov (United States)

    Bougher, S. W.

    2004-01-01

    The detailed characterization of the Mars upper atmosphere is important for future Mars aerobraking activities. Solar cycle, seasonal, and dust trends (climate) as well as planetary wave activity (weather) are crucial to quantify in order to improve our ability to reasonably depict the state of the Mars upper atmosphere over time. To date, our best information is found in the Mars Global Surveyor (MGS) Accelerometer (ACC) database collected during Phase 1 (Ls = 184 - 300; F10.7 = 70 - 90) and Phase 2 (Ls = 30 - 90; F10.7 = 90 - 150) of aerobraking. This database (100 - 170 km) consists of thermospheric densities, temperatures, and scale heights, providing our best constraints for exercising the coupled Mars General Circulation Model (MGCM) and the Mars Thermospheric General Circulation Model (MTGCM). The Planetary Data System (PDS) contains level 0 and 2 MGS Accelerometer data, corresponding to atmospheric densities along the orbit track. Level 3 products (densities, temperatures, and scale heights at constant altitudes) are also available in the PDS. These datasets provide the primary model constraints for the new MGCM-MTGCM simulations summarized in this report. Our strategy for improving the characterization of the Mars upper atmospheres using these models has been three-fold : (a) to conduct data-model comparisons using the latest MGS data covering limited climatic and weather conditions at Mars, (b) to upgrade the 15-micron cooling and near-IR heating rates in the MGCM and MTGCM codes for ad- dressing climatic variations (solar cycle and seasonal) important in linking the lower and upper atmospheres (including migrating tides), and (c) to exercise the detailed coupled MGCM and MTGCM codes to capture and diagnose the planetary wave (migrating plus non-migrating tidal) features throughout the Mars year. Products from this new suite of MGCM-MTGCM coupled simulations are being used to improve our predictions of the structure of the Mars upper atmosphere for the

  3. Glycogen Synthase in Sertoli Cells: More Than Glycogenesis?

    Science.gov (United States)

    Maldonado, Rodrigo; Mancilla, Héctor; Villarroel-Espíndola, Franz; Slebe, Felipe; Slebe, Juan Carlos; Méndez, Raúl; Guinovart, Joan J; Concha, Ilona I

    2016-11-01

    Sertoli cell metabolism actively maintains the nutritional needs of germ cells. It has been described that after glucose incorporation in Sertoli cells, less than 1% is converted to glycogen suggesting low levels of glycogen synthase activity. Phosphorylation of muscle glycogen synthase (MGS) at serine 640 (pS640MGS) decreases its activity, and this form of the enzyme was discovered as a non-ribosomal protein that modulates the translation of a subset of transcripts in HeLa cells. The aim of our study was to functionally characterize MGS in cultured Sertoli cells, as well as to explore this new feature related to RNA molecules. We detected MGS in the cytoplasm of Sertoli cells as well as in the nuclei. The activity rates of the enzyme were extremely low indicating that MGS is expressed but almost inactive. Protein targeting to glycogen (PTG) overexpression was performed to activate MGS by dephosphorylation. PTG induced glycogen synthesis massively, confirming that this enzyme is present but inactive. This finding correlates with high levels of pS640MGS, which were assayed by phosphatase treatment. To explore a putative new function for MGS in Sertoli cells, we performed RNA immunoprecipitation coupled to microarray studies. The results revealed that MGS co-immunoprecipitated with the several mRNAs and also rRNAs. These findings indicate that MGS is expressed Sertoli cells but in an inactive form, and also support a possibly novel feature of this metabolic enzyme associated with RNA-related molecules. J. Cell. Biochem. 117: 2597-2607, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Grading of meningeal solitary fibrous tumors/hemangiopericytomas: analysis of the prognostic value of the Marseille Grading System in a cohort of 132 patients.

    Science.gov (United States)

    Macagno, Nicolas; Vogels, Rob; Appay, Romain; Colin, Carole; Mokhtari, Karima; Küsters, Benno; Wesseling, Pieter; Figarella-Branger, Dominique; Flucke, Uta; Bouvier, Corinne

    2018-03-30

    The finding that meningeal solitary fibrous tumors (SFTs) and meningeal hemangiopericytomas (HPCs) are both characterized by NAB2-STAT6 gene fusion has pushed their inclusion in the WHO 2016 Classification of tumors of the central nervous system (CNS) as different manifestations of the same entity. Given that the clinical behavior of the CNS SFT/HPC spectrum ranges from benign to malignant, it is presently unclear whether the grading criteria are still adequate. Here, we present the results of a study that analyzed the prognostic value of an updated version of the Marseille Grading System (MGS) in a retrospectively assembled cohort of 132 primary meningeal SFTs/HPCs with nuclear overexpression of STAT6. The median patient follow-up was 64 months (range 4-274 months); 73 cases (55%) were MGS I, 50 cases (38%) MGS II and 9 cases (7%) were MGS III. Progression-free survival (PFS) and disease-specific survival (DSS) were investigated using univariate analysis: the prognostic factors for PFS included MGS, extent of surgery, radiotherapy, chemotherapy and mitotic activity ≥5/10 high-power field (HPF). Moreover, MGS, radiotherapy, mitotic activity ≥5/10 HPF, and necrosis were the prognostic factors measured for DSS. In multivariate analysis, extent of surgery, mitotic activity ≥5/10 HPF, MGS I and MGS III were the independent prognostic factors measured for PFS while necrosis, MGS III and radiotherapy were the independent prognostic factors for DSS. In conclusion, our results show that assessing the malignancy risk of SFT/HPC should not rely on one single criterion like mitotic activity. Therefore, MGS is useful as it combines the value of different criteria. In particular, the combination of a high mitotic activity and necrosis (MGS III) indicates a particularly poor prognosis. © 2018 International Society of Neuropathology.

  5. The Post-polyketide Synthase Steps in iso-Migrastatin Biosynthesis Featuring Tailoring Enzymes with Broad Substrate Specificity

    Science.gov (United States)

    Ma, Ming; Kwong, Thomas; Lim, Si-Kyu; Ju, Jianhua; Lohman, Jeremy R.; Shen, Ben

    2013-01-01

    The iso-migrastatin (iso-MGS) biosynthetic gene cluster from Streptomyces platensis NRRL 18993 consists of 11 genes, featuring an acyltransferase (AT)-less type I polyketide synthase (PKS) and three tailoring enzymes MgsIJK. Systematic inactivation of mgsIJK in S. platensis enabled us to (i) identify two nascent products (10 and 13) of the iso-MGS AT-less type I PKS, establishing an unprecedented novel feature for AT-less type I PKSs, and (ii) account for the formation of all known post-PKS biosynthetic intermediates (10-17) generated by the three tailoring enzymes MgsIJK, which possessed significant substrate promiscuities. PMID:23394593

  6. Energy Sharing for Interconnected Microgrids with a Battery Storage System and Renewable Energy Sources Based on the Alternating Direction Method of Multipliers

    Directory of Open Access Journals (Sweden)

    Nian Liu

    2018-04-01

    Full Text Available In order to facilitate the local sharing of renewable energy, an energy sharing management method of multiple microgrids (MGs with a battery energy storage system (BESS and renewable energy sources (RESs is developed. First, a virtual entity named the energy sharing provider (ESP, which acts as an agent for MGs, is introduced to minimize the power loss cost. Second, a distributed optimal model and a two-level iterative algorithm for the MGs and ESP are proposed, which minimize the total operation cost including purchasing electricity cost, energy storage cost and power loss cost. Based on the energy sharing framework, considering the local objectives of MGs and the objective of ESP, the optimal scheduling can be achieved through the bidirectional interaction between MGs and ESP. During the optimization, the shared information between MGs and ESP is limited to expected exchange power, which protects the privacy of MGs and ESP. Finally, the effectiveness of the proposed model and algorithm in different scenarios is verified through a case study.

  7. Effect of the Cu and Ni content on the crystallization temperature and crystallization mechanism of La–Al–Cu(Ni metallic glasses

    Directory of Open Access Journals (Sweden)

    Peiyou Li

    2016-02-01

    Full Text Available The effect of the Cu and Ni content on the crystallization mechanism and the crystallization temperatures of La–Al–Cu(Ni metallic glasses (MGs was studied by differential scanning calorimetry (DSC. The experimental results have shown that the DSC curves obtained for the La–Al–Cu and La–Al–Ni MGs exhibit two and three crystallization temperatures, respectively. The crystallization temperatures of the La–Al–Cu and La–Al–Ni MGs result from the merging and splitting of thermal events related to the corresponding eutectic atomic pairs in the La72Cu28 and La81.6Al18.4 MGs, and La72Ni28 and La81.6Al18.4 MGs, respectively. In addition, Al- and Ni-containing clusters with weak or strong atomic interaction in the Al–Ni atomic pairs strongly affect the crystallization mechanism and thus the crystallization temperature of La–Al–Ni MGs. This study provides a novel understanding of the relation between the crystallization temperature and the underlying crystallization mechanisms in La–Al–Cu(Ni MGs.

  8. Theoretical study of the low-lying electronic states of magnesium sulfide cation including spin-orbit interaction

    Science.gov (United States)

    Chen, Peng; Wang, Ning; Li, Song; Chen, Shan-Jun

    2017-11-01

    Highly correlated ab initio calculations have been performed for an accurate determination of electronic structures and spectroscopic features for the low-lying electronic states of the MgS+ cation. The potential energy curves for the four Λ-S states correlating to the lowest dissociation asymptote are studied for the first time. Four Λ-S states split into nine Ω states through the spin-orbit coupling effect. Accurate spectroscopic constants are deduced for all bound states. The spin-orbit couplings and the transition dipole moments, as well as the PECs, are utilized to calculate Franck-Condon factors and radiative lifetimes of the vibrational levels. To verify our computational accuracy, analogous calculations for the ground state of MgS are also carried out, and our derived results are in reasonable agreement with available experimental data. In addition, photoelectron spectrum of MgS has been simulated. The predictive results are anticipated to serve as guidelines for further researches such as assisting laboratorial detections and analyzing observed spectrum.

  9. The Annual Cycle of Water Vapor on Mars as Observed by the Thermal Emission Spectrometer

    Science.gov (United States)

    Smith, Michael D.; Vondrak, Richard R. (Technical Monitor)

    2001-01-01

    Spectra taken by the Mars Global Surveyor Thermal Emission Spectrometer (TES) have been used to monitor the latitude, longitude, and seasonal dependence of water vapor for over one full Martian year (March 1999-March 2001). A maximum in water vapor abundance is observed at high latitudes during mid-summer in both hemispheres, reaching a maximum value of approximately 100 pr-micrometer in the north and approximately 50 pr-micrometer in the south. Low water vapor abundance (water vapor. The latitudinal and seasonal dependence of the decay of the northern summer water vapor maximum implies cross-equatorial transport of water to the southern hemisphere, while there is little or no corresponding transport during the decay of the southern hemisphere summer maximum. The latitude-longitude dependence of annually-averaged water vapor (corrected for topography) has a significant positive correlation with albedo and significant negative correlations with thermal inertia and surface pressure. Comparison of TES results with those retrieved from the Viking Orbiter Mars Atmospheric Water Detectors (MAWD) experiments shows some similar features, but also many significant differences. The southern hemisphere maximum observed by TES was not observed by MAWD and the large latitudinal gradient in annually-averaged water vapor observed by MAWD does not appear in the TES results.

  10. Modern methods of surveyor observations in opencast mining under complex hydrogeological conditions.

    Science.gov (United States)

    Usoltseva, L. A.; Lushpei, V. P.; Mursin, VA

    2017-10-01

    The article considers the possibility of linking the modern methods of surveying security of open mining works to improve industrial safety in the Primorsky Territory, as well as their use in the educational process. Industrial Safety in the management of Surface Mining depends largely on the applied assessment methods and methods of stability of pit walls and slopes of dumps in the complex mining and hydro-geological conditions.

  11. Processing of A New Digital Orthoimage Map of The Martian Western Hemisphere Using Data Obtained From The Mars Orbiter Camera At A Resolution of 256 Pixel/deg

    Science.gov (United States)

    Wählisch, M.; Niedermaier, G.; van Gasselt, S.; Scholten, F.; Wewel, F.; Roatsch, T.; Matz, K.-D.; Jaumann, R.

    We present a new digital orthoimage map of Mars using data obtained from the CCD line scanner Mars Orbiter Camera (MOC) of the Mars Global Surveyor Mis- sion (MGS) [1,2]. The map covers the Mars surface from 0 to 180 West and from 60 South to 60 North with the MDIM2 resolution of 256 pixel/degree and size. Image data processing has been performed using multiple programs, developed by DLR, Technical University of Berlin [3], JPL, and the USGS. 4,339 Context and 183 Geodesy images [2] were included. After radiometric corrections, the images were Mars referenced [4], geometrically corrected [5] and orthoprojected using a global Martian Digital Terrain Model (DTM) with a resolution of 64 pixel/degree, developed at DLR and based on MGS Mars Orbiter Laser Altimeter (MOLA) data [6]. To elim- inate major differences in brightness between the individual images of the mosaics, high- and low-pass filter processing techniques were applied for each image. After filtering, the images were mosaicked without registering or using block adjustment techniques in order to improve the geometric quality. It turns out that the accuracy of the navigation data has such a good quality that the orthoimages fit very well to each other. When merging the MOC mosaic with the MOLA data using IHS- trans- formation, we recognized very good correspondence between these two datasets. We create a topographic image map of the Coprates region (MC­18) adding contour lines derived from the global DTM to the mosaic. These maps are used for geological and morphological interpretations in order to review and improve our current Viking-based knowledge about the Martian surface. References: [1] www.mssss.com, [2] Caplinger, M. and M. Malin, "The Mars Or- biter Camera Geodesy Campaign, JGR, in press, [3] Scholten, F., Vol XXXI, Part B2, Wien 1996, p.351-356, [4] naïf.jpl.nasa.gov, [5] R.L.Kirk. et al. (2001), "Geometric Calibration of the Mars Orbiter Cameras and Coalignment with Mars Orbiter Laser Altimeter

  12. Study of the Radial Peripapillary Capillary Network in Congenital Optic Disc Anomalies With Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Cennamo, Gilda; Rossi, Claudia; Ruggiero, Pasquale; de Crecchio, Giuseppe; Cennamo, Giovanni

    2017-04-01

    To evaluate the radial peripapillary capillary network with optical coherence tomography angiography (angio-OCT) in morning glory syndrome (MGS), optic disc colobomas, and optic disc pits, and to explore possible correlations between the neural vascular structure and the pathogenesis of congenital optic disc anomalies. Prospective observational comparative case series. Fifteen eyes of 15 patients with congenital optic disc anomalies were enrolled in this study. All patients underwent angio-OCT. The scans were centered on optic discs. The mean age at presentation was 33 years (range: 19-50 years). Congenital optic disc anomalies were identified in all 15 eyes. Three eyes had the characteristic funduscopic signs of MGS, and angio-OCT scans of the peripapillary retina revealed a dense microvascular network. Optic disc colobomas were found in 5 eyes, and the characteristic funduscopic signs of optic pits were found in 7 eyes. Angio-OCT showed the absence of a radial peripapillary microvascular network in these 12 eyes. The finding that angio-OCT scans confirmed the presence of a peripapillary microvascular network only in MGS cases supports the hypothesis that a primary neuroectodermal abnormality and a secondary mesenchymal abnormality leads to MGS. Angio-OCT is a safe, rapid imaging technique that could shed light on the pathogenesis of rare diseases of the optic disc. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Short-term secular change in height, body mass and Tanner-Whitehouse 3 skeletal maturity of Madeira youth, Portugal.

    Science.gov (United States)

    Freitas, Duarte; Malina, Robert M; Maia, José; Lefevre, Johan; Stasinopoulos, Mikis; Gouveia, Élvio; Claessens, Albrecht; Thomis, Martine; Lausen, Berthold

    2012-05-01

    Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking. To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs). Data for 2856 children and adolescents of 4-17 years, 1412 boys and 1444 girls, from The 'Madeira Growth Study' (MGS; 1996-1998) and from the'Healthy Growth of Madeira Children Study' (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods. Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8 cm in boys and 5.5 cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively. The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs.

  14. Modeling of the Martian environment for radiation analysis

    International Nuclear Information System (INIS)

    De Angelis, G.; Wilson, J.W.; Clowdsley, M.S.; Qualls, G.D.; Singleterry, R.C.

    2006-01-01

    A model for the radiation environment to be found on the planet Mars due to Galactic Cosmic Rays (GCR) has been developed. Solar modulated primary particles rescaled for conditions at Mars are transported through the Martian atmosphere down to the surface, with altitude and backscattering patterns taken into account. The altitude to compute the atmospheric thickness profile has been determined by using a model for the topography based on the data provided by the Mars Orbiter Laser Altimeter (MOLA) instrument on board the Mars Global Surveyor (MGS) spacecraft. The Mars surface composition has been modeled based on averages over the measurements obtained from orbiting spacecraft and at various landing sites, taking into account the possible volatile inventory (e.g. CO 2 and H 2 O ices) along with its time variations throughout the Martian year. The Mars Radiation Environment Model has been made available worldwide through the Space Ionizing Radiation Effects and Shielding Tools (SIREST) website, a project of NASA Langley Research Center. This site has been developed to provide the scientific and engineering communities with an interactive site containing a variety of environmental models, shield evaluation codes, and radiation response models to allow a thorough assessment of ionizing radiation risk for current and future space missions

  15. The kinetic origin of delayed yielding in metallic glasses

    International Nuclear Information System (INIS)

    Ye, Y. F.; Liu, X. D.; Wang, S.; Liu, C. T.; Yang, Y.; Fan, J.

    2016-01-01

    Recent experiments showed that irreversible structural change or plasticity could occur in metallic glasses (MGs) even within the apparent elastic limit after a sufficiently long waiting time. To explain this phenomenon, a stochastic shear transformation model is developed based on a unified rate theory to predict delayed yielding in MGs, which is validated afterwards through extensive atomistic simulations carried out on different MGs. On a fundamental level, an analytic framework is established in this work that links time, stress, and temperature altogether into a general yielding criterion for MGs.

  16. The kinetic origin of delayed yielding in metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Y. F.; Liu, X. D.; Wang, S.; Liu, C. T.; Yang, Y., E-mail: yonyang@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, Centre for Advanced Structural Materials, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong (China); Fan, J. [Department of Applied Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong (China)

    2016-06-20

    Recent experiments showed that irreversible structural change or plasticity could occur in metallic glasses (MGs) even within the apparent elastic limit after a sufficiently long waiting time. To explain this phenomenon, a stochastic shear transformation model is developed based on a unified rate theory to predict delayed yielding in MGs, which is validated afterwards through extensive atomistic simulations carried out on different MGs. On a fundamental level, an analytic framework is established in this work that links time, stress, and temperature altogether into a general yielding criterion for MGs.

  17. Non-Newtonian plastic flow of a Ni-Si-B metallic glass at low stresses

    International Nuclear Information System (INIS)

    Csach, K.; Fursova, Y.V.; Khonik, V.A.; Ocelik, V.

    1998-01-01

    The problem of the rheological behavior of metallic glasses (MGs) is quite important both from theoretical and practical viewpoints. Early experiments carried out on MGs at temperatures T > 300 K using low shear stress levels revealed plastic flow to be Newtonian while measurements at relative high shear stresses (more than 200 to 400 MPa, depending on temperature, thermal prehistory of samples and chemical composition) indicated a non-linear behavior with 1 < m < 12. Numerous investigations performed later both on as-cast and relaxed MGs of various chemical compositions using a number of testing methods (tensile creep, tensile and bend stress relaxation) showed that a transition from Newtonian behavior at low stresses to a non-linear flow at high stresses was observed. At present, such a situation is considered to be generally accepted. The authors performed precise creep measurements of a Ni-Si-B metallic glass. The results obtained indicate that plastic flow in this case at low tensile stress (12 le σ le 307 MPa) is clearly non-Newtonian and, consequently, the viscosity is stress dependent

  18. Comparison of Physical Properties of Marine and Arctic Gas-Hydrate-Bearing Deposits

    Science.gov (United States)

    Winters, W. J.; Walker, M.; Collett, T. S.; Bryant, S. L.; Novosel, I.; Wilcox-Cline, R.; Bing, J.; Gomes, M. L.

    2009-12-01

    with both characteristics. Maximum MGS measured on more than 1200 samples was 46 µm, but the average MGS for 14 wells varied from 5 to 10 µm. At Site 10, in the Krishna-Godavari Basin, GH was observed in several morphologic configurations, including complex high-angle planar and rotational veins, solid nodules, and disseminated, in sediment with average MGS of 5 µm, liquid limits between 70 and 98, and plastic limits between 33 and 49. Sediment in a 692-m deep well drilled off the Andaman Islands sporadically hosted disseminated GH in thin coarser-grained ash beds and ash-rich zones. Average and maximum MGS in this well is 6 and 17 µm, respectively. To date, sandy GH reservoirs (with some exceptions, e.g., Nankai Trough) are typically associated with the arctic. However, the presence of thick offshore sand-rich GHB reservoirs is the subject of current investigations, such as by the Gulf of Mexico Joint Industry Project (JIP).

  19. Hierarchical Control for Multiple DC-Microgrids Clusters

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2014-01-01

    DC microgrids (MGs) have gained research interest during the recent years because of many potential advantages as compared to the ac system. To ensure reliable operation of a low-voltage dc MG as well as its intelligent operation with the other DC MGs, a hierarchical control is proposed in this p......DC microgrids (MGs) have gained research interest during the recent years because of many potential advantages as compared to the ac system. To ensure reliable operation of a low-voltage dc MG as well as its intelligent operation with the other DC MGs, a hierarchical control is proposed...

  20. Low-Voltage Ride-Through Operation of Power Converters in Grid-Interactive Microgrids by Using Negative-Sequence Droop Control

    DEFF Research Database (Denmark)

    Zhao, Xin; Guerrero, Josep M.; Savaghebi, Mehdi

    2017-01-01

    of the utility grid during grid faults. In this paper, a LVRT control strategy based on positive/negative sequence droop control is proposed for grid-interactive MGs to ride-through voltage sags with not only inductive/resistive, but also complex line impedance. By using the proposed control strategy, MGs can......Due to the increasing penetration level of microgrids (MGs), it becomes a critical issue for MGs to help sustaining power system stability. Therefore, ancillary services, such as the low-voltage ride-through (LVRT) capability should be incorporated in MGs in order to guarantee stable operation...... support the grid voltage, make profits, and also ride-through the voltage dip during the whole fault period. A two layer hierarchical control strategy is proposed in this paper. The primary controller consists of voltage and current inner loops, a conventional droop control and a virtual impedance loop...

  1. Surface Chemistry Interactions of Cationorm with Films by Human Meibum and Tear Film Compounds

    Directory of Open Access Journals (Sweden)

    Georgi As. Georgiev

    2017-07-01

    Full Text Available Cationorm® (CN cationic nanoemulsion was demonstrated to enhance tear film (TF stability in vivo possibly via effects on tear film lipid layer (TFLL. Therefore the interactions of CN with human meibum (MGS and TFLL in vitro and in vivo deserve special study. MGS and CN were spread at the air/water interface of a Langmuir surface balance to ensure a range of MGS/CN oil phase ratios: 20/1, 10/1, 5/1, 3/1, 2/1 and 1/1. The films capability to reorganize during dynamic area changes was evaluated via the surface pressure-area compression isotherms and step/relaxation dilatational rheology studies. Films structure was monitored with Brewster angle microscopy. CN/TFLL interactions at the ocular surface were monitored with non-contact specular microscopy. The in vitro studies of MGS/CN layers showed that (i CN inclusion (at fixed MGS content increased film elasticity and thickness and that (ii CN can compensate for moderate meibum deficiency in MGS/CN films. In vivo CN mixed with TFLL in a manner similar to CN/MGS interactions in vitro, and resulted in enhanced thickness of TFLL. In vitro and in vivo data complement each other and facilitated the study of the composition-structure-function relationship that determines the impact of cationic nanoemulsions on TF.

  2. Landing Site Studies Using High Resolution MGS Crater Counts and Phobos-2 Termoskan Data

    Science.gov (United States)

    Hartmann, Willian K.; Berman, Daniel C.; Betts, Bruce H.

    1999-06-01

    We have examined a number of potential landing sites to study effects associated with impact crater populations. We used Mars Global Surveyor high resolution MOC images, and emphasized "ground truth" by calibrating with the MOC images of Viking 1 and Pathfinder sites. An interesting result is that most of Mars (all surfaces with model ages older than 100 My) have small crater populations in saturation equilibrium below diameters D approx. = 60 meters (and down to the smallest resolvable, countable sizes, approx. = 15 m). This may have consequences for preservation of surface bedrock exposures accessible to rovers. In the lunar maria, a similar saturation equilibrium is reached for crater diameters below about 300 meters, and this has produced a regolith depth of about 10-20 meters in those areas. Assuming linear scaling, we infer that saturation at D approx. = 60 m would produce gardening and Martian regolith, or fragmental layers, about 2 to 4 meters deep over all but extremely young surfaces (such as the very fresh thin surface flows in southern Elysium Planitia, which have model ages around 10 My or less). This result may explain the global production of ubiquitous dust and fragmental material on Mars. Removal of fines may leave the boulders that have been seen at all three of the first landing sites. Accumulation of the fines elsewhere produces dunes. Due to these effects, it may be difficult to set down rovers in areas where bedrock is well preserved at depths of centimeters, unless we find cliff sides or areas of deflation where wind has exposed clean surfaces (among residual boulders?) We have also surveyed the PHOBOS 2 Termoskan data to look for regions of thermal anomalies that might produce interesting landing sites. For landing site selection, two of the more interesting types of features are thermally distinct ejecta blankets and thermally distinct channels and valleys. Martian "thermal features" such as these that correlate closely with nonaeolian

  3. The Age-Related Macular Degeneration Complex: Linking Epidemiology and Histopathology Using the Minnesota Grading System (The Inaugural Frederick C. Blodi Lecture).

    Science.gov (United States)

    Olsen, Timothy W; Bottini, Alexander R; Mendoza, Pia; Grossniklausk, Hans E

    2015-09-01

    To describe the histopathologic findings of the four stages of age-related macular degeneration (AMD) as defined by the Age-Related Eye Disease Study (AREDS) using the Minnesota grading system (MGS). There are no animal models for AMD. Eye banks enable access to human tissue with AMD. The level of AMD (grades 1 through 4) as defined by AREDS is determined ex vivo using the MGS. The AREDS has the largest collection to date of prospectively gathered data on the natural history of AMD. Since the MGS uses the same clinical criteria as AREDS, the addition of histopathologic findings of graded tissue confirms important pathophysiology at each stage of AMD. Four eye bank eyes were graded according to the MGS. Only the right eyes were dissected for phenotype grading. The fellow (left) eyes were fixed for histopathologic study. The eyes were serially sectioned (7 μm) through the macula. Individual slides were examined, and a two-dimensional reconstruction of the topography of the macula was created for each donor. Selected, unstained slides were used for immunohistochemical staining. In one donor, portions of tissue were obtained for transmission electron microscopic (TEM) processing. Donor 1 had a rare hard, nodular druse (MGS1). Donor 2 had intermediate confluent drusen (MGS2). Donor 3 had numerous intermediate drusen (MGS3) in the right eye. Histopathology of the fellow left showed basal laminar deposits (BLamD), soft drusen, and an area of occult choroidal neovascularization underlying the retinal pigment epithelium (RPE) with endothelial cells (CD31-positive). Donor 4 also had MGS 3 along with reticular pseudodrusen (RPD). Histologic and TEM examination demonstrated diffuse BLamD, thickening of Bruch's membrane, hard drusen, and focal nodules underlying the RPE that corresponded to the RPD. EM examination demonstrated both BLamD and electron-dense material located just external to the elastic layer of Bruch's membrane. Eye bank eyes graded using the MGS serve as an

  4. The Nine-Step Minnesota Grading System for Eyebank Eyes With Age Related Macular Degeneration: A Systematic Approach to Study Disease Stages.

    Science.gov (United States)

    Olsen, Timothy W; Liao, Albert; Robinson, Hershonna S; Palejwala, Neal V; Sprehe, Nicholas

    2017-10-01

    To refine the Minnesota Grading System (MGS) using definitions from the Age-Related Eye Disease Studies (AREDS) into a nine-step grading scale (MGS-9). A nine-step grading scale descriptive analysis using three key phenotypic features (total drusen area, increased, and decreased pigmentation) of human eyebank eyes that were graded according to definitions from the AREDS criteria in order to harmonize studies of disease progression for research involving human tissue. From 2005 through February 2017, we have analyzed 1159 human eyes, procured from two eyebanks. Each macula was imaged using high-resolution, stereoscopic color fundus photography with both direct- and transillumination. Fundus images were digitally overlaid with a grading template and triangulated for foveal centration. We documented and stratified risk for each globe by applying the AREDS nine-step grading scale to the key clinical features from the MGS-9. We found a good distribution within the MGS categories (1-9) with few level eight globes. Eyes were processed within 12.1 ± 6.3, hours from the time of death through imaging, dissection, and freezing or fixation. Applying the MGS-9 to 331 pairs (662 eyes were simultaneously graded), 84% were within one-grading step and 93% within two steps of the fellow eye. We also document reticular pseudodrusen, basal laminar drusen, and pattern dystrophy. The MGS nine-step grading scale enables researchers using human tissue to refine the risk assessment of donor tissue. This analysis will harmonize results among researchers when grading human tissue using MGS criteria. Most importantly, the MGS-9 links directly to the known risk for progression from the AREDS.

  5. A Critical Review on Metallic Glasses as Structural Materials for Cardiovascular Stent Applications.

    Science.gov (United States)

    Jafary-Zadeh, Mehdi; Praveen Kumar, Gideon; Branicio, Paulo Sergio; Seifi, Mohsen; Lewandowski, John J; Cui, Fangsen

    2018-02-27

    Functional and mechanical properties of novel biomaterials must be carefully evaluated to guarantee long-term biocompatibility and structural integrity of implantable medical devices. Owing to the combination of metallic bonding and amorphous structure, metallic glasses (MGs) exhibit extraordinary properties superior to conventional crystalline metallic alloys, placing them at the frontier of biomaterials research. MGs have potential to improve corrosion resistance, biocompatibility, strength, and longevity of biomedical implants, and hence are promising materials for cardiovascular stent applications. Nevertheless, while functional properties and biocompatibility of MGs have been widely investigated and validated, a solid understanding of their mechanical performance during different stages in stent applications is still scarce. In this review, we provide a brief, yet comprehensive account on the general aspects of MGs regarding their formation, processing, structure, mechanical, and chemical properties. More specifically, we focus on the additive manufacturing (AM) of MGs, their outstanding high strength and resilience, and their fatigue properties. The interconnection between processing, structure and mechanical behaviour of MGs is highlighted. We further review the main categories of cardiovascular stents, the required mechanical properties of each category, and the conventional materials have been using to address these requirements. Then, we bridge between the mechanical requirements of stents, structural properties of MGs, and the corresponding stent design caveats. In particular, we discuss our recent findings on the feasibility of using MGs in self-expandable stents where our results show that a metallic glass based aortic stent can be crimped without mechanical failure. We further justify the safe deployment of this stent in human descending aorta. It is our intent with this review to inspire biodevice developers toward the realization of MG-based stents.

  6. A Critical Review on Metallic Glasses as Structural Materials for Cardiovascular Stent Applications

    Directory of Open Access Journals (Sweden)

    Mehdi Jafary-Zadeh

    2018-02-01

    Full Text Available Functional and mechanical properties of novel biomaterials must be carefully evaluated to guarantee long-term biocompatibility and structural integrity of implantable medical devices. Owing to the combination of metallic bonding and amorphous structure, metallic glasses (MGs exhibit extraordinary properties superior to conventional crystalline metallic alloys, placing them at the frontier of biomaterials research. MGs have potential to improve corrosion resistance, biocompatibility, strength, and longevity of biomedical implants, and hence are promising materials for cardiovascular stent applications. Nevertheless, while functional properties and biocompatibility of MGs have been widely investigated and validated, a solid understanding of their mechanical performance during different stages in stent applications is still scarce. In this review, we provide a brief, yet comprehensive account on the general aspects of MGs regarding their formation, processing, structure, mechanical, and chemical properties. More specifically, we focus on the additive manufacturing (AM of MGs, their outstanding high strength and resilience, and their fatigue properties. The interconnection between processing, structure and mechanical behaviour of MGs is highlighted. We further review the main categories of cardiovascular stents, the required mechanical properties of each category, and the conventional materials have been using to address these requirements. Then, we bridge between the mechanical requirements of stents, structural properties of MGs, and the corresponding stent design caveats. In particular, we discuss our recent findings on the feasibility of using MGs in self-expandable stents where our results show that a metallic glass based aortic stent can be crimped without mechanical failure. We further justify the safe deployment of this stent in human descending aorta. It is our intent with this review to inspire biodevice developers toward the realization

  7. A Critical Review on Metallic Glasses as Structural Materials for Cardiovascular Stent Applications

    Science.gov (United States)

    Jafary-Zadeh, Mehdi; Praveen Kumar, Gideon

    2018-01-01

    Functional and mechanical properties of novel biomaterials must be carefully evaluated to guarantee long-term biocompatibility and structural integrity of implantable medical devices. Owing to the combination of metallic bonding and amorphous structure, metallic glasses (MGs) exhibit extraordinary properties superior to conventional crystalline metallic alloys, placing them at the frontier of biomaterials research. MGs have potential to improve corrosion resistance, biocompatibility, strength, and longevity of biomedical implants, and hence are promising materials for cardiovascular stent applications. Nevertheless, while functional properties and biocompatibility of MGs have been widely investigated and validated, a solid understanding of their mechanical performance during different stages in stent applications is still scarce. In this review, we provide a brief, yet comprehensive account on the general aspects of MGs regarding their formation, processing, structure, mechanical, and chemical properties. More specifically, we focus on the additive manufacturing (AM) of MGs, their outstanding high strength and resilience, and their fatigue properties. The interconnection between processing, structure and mechanical behaviour of MGs is highlighted. We further review the main categories of cardiovascular stents, the required mechanical properties of each category, and the conventional materials have been using to address these requirements. Then, we bridge between the mechanical requirements of stents, structural properties of MGs, and the corresponding stent design caveats. In particular, we discuss our recent findings on the feasibility of using MGs in self-expandable stents where our results show that a metallic glass based aortic stent can be crimped without mechanical failure. We further justify the safe deployment of this stent in human descending aorta. It is our intent with this review to inspire biodevice developers toward the realization of MG-based stents

  8. Two models of minimalist, incremental syntactic analysis.

    Science.gov (United States)

    Stabler, Edward P

    2013-07-01

    Minimalist grammars (MGs) and multiple context-free grammars (MCFGs) are weakly equivalent in the sense that they define the same languages, a large mildly context-sensitive class that properly includes context-free languages. But in addition, for each MG, there is an MCFG which is strongly equivalent in the sense that it defines the same language with isomorphic derivations. However, the structure-building rules of MGs but not MCFGs are defined in a way that generalizes across categories. Consequently, MGs can be exponentially more succinct than their MCFG equivalents, and this difference shows in parsing models too. An incremental, top-down beam parser for MGs is defined here, sound and complete for all MGs, and hence also capable of parsing all MCFG languages. But since the parser represents its grammar transparently, the relative succinctness of MGs is again evident. Although the determinants of MG structure are narrowly and discretely defined, probabilistic influences from a much broader domain can influence even the earliest analytic steps, allowing frequency and context effects to come early and from almost anywhere, as expected in incremental models. Copyright © 2013 Cognitive Science Society, Inc.

  9. Methylglyoxal synthase regulates cell elongation via alterations of cellular methylglyoxal and spermidine content in Bacillus subtilis.

    Science.gov (United States)

    Shin, Sang-Min; Song, Sung-Hyun; Lee, Jin-Woo; Kwak, Min-Kyu; Kang, Sa-Ouk

    2017-10-01

    Methylglyoxal regulates cell division and differentiation through its interaction with polyamines. Loss of their biosynthesizing enzyme causes physiological impairment and cell elongation in eukaryotes. However, the reciprocal effects of methylglyoxal and polyamine production and its regulatory metabolic switches on morphological changes in prokaryotes have not been addressed. Here, Bacillus subtilis methylglyoxal synthase (mgsA) and polyamine biosynthesizing genes encoding arginine decarboxylase (SpeA), agmatinase (SpeB), and spermidine synthase (SpeE), were disrupted or overexpressed. Treatment of 0.2mM methylglyoxal and 1mM spermidine led to the elongation and shortening of B. subtilis wild-type cells to 12.38±3.21μm (P<0.05) and 3.24±0.73μm (P<0.01), respectively, compared to untreated cells (5.72±0.68μm). mgsA-deficient (mgsA - ) and -overexpressing (mgsA OE ) mutants also demonstrated cell shortening and elongation, similar to speB- and speE-deficient (speB - and speE - ) and -overexpressing (speB OE and speE OE ) mutants. Importantly, both mgsA-depleted speB OE and speE OE mutants (speB OE /mgsA - and speE OE /mgsA - ) were drastically shortened to 24.5% and 23.8% of parental speB OE and speE OE mutants, respectively. These phenotypes were associated with reciprocal alterations of mgsA and polyamine transcripts governed by the contents of methylglyoxal and spermidine, which are involved in enzymatic or genetic metabolite-control mechanisms. Additionally, biophysically detected methylglyoxal-spermidine Schiff bases did not affect morphogenesis. Taken together, the findings indicate that methylglyoxal triggers cell elongation. Furthermore, cells with methylglyoxal accumulation commonly exhibit an elongated rod-shaped morphology through upregulation of mgsA, polyamine genes, and the global regulator spx, as well as repression of the cell division and shape regulator, FtsZ. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Software Surveyor

    National Research Council Canada - National Science Library

    Wells, Davide

    2003-01-01

    .... The non-intrusive gauges illustrate the interaction patters, how far the effects of changes can propagate and whether an anticipated action is likely to be safe and identify subtle differences...

  11. Evaluating health worker performance in Benin using the simulated client method with real children.

    Science.gov (United States)

    Rowe, Alexander K; Onikpo, Faustin; Lama, Marcel; Deming, Michael S

    2012-10-08

    The simulated client (SC) method for evaluating health worker performance utilizes surveyors who pose as patients to make surreptitious observations during consultations. Compared to conspicuous observation (CO) by surveyors, which is commonly done in developing countries, SC data better reflect usual health worker practices. This information is important because CO can cause performance to be better than usual. Despite this advantage of SCs, the method's full potential has not been realized for evaluating performance for pediatric illnesses because real children have not been utilized as SCs. Previous SC studies used scenarios of ill children that were not actually brought to health workers. During a trial that evaluated a quality improvement intervention in Benin (the Integrated Management of Childhood Illness [IMCI] strategy), we conducted an SC survey with adult caretakers as surveyors and real children to evaluate the feasibility of this approach and used the results to assess the validity of CO. We conducted an SC survey and a CO survey (one right after the other) of health workers in the same 55 health facilities. A detailed description of the SC survey process was produced. Results of the two surveys were compared for 27 performance indicators using logistic regression modeling. SC and CO surveyors observed 54 and 185 consultations, respectively. No serious problems occurred during the SC survey. Performance levels measured by CO were moderately higher than those measured by SCs (median CO - SC difference = 16.4 percentage-points). Survey differences were sometimes much greater for IMCI-trained health workers (median difference = 29.7 percentage-points) than for workers without IMCI training (median difference = 3.1 percentage-points). SC surveys can be done safely with real children if appropriate precautions are taken. CO can introduce moderately large positive biases, and these biases might be greater for health workers exposed to quality improvement

  12. Considering treatment of male genital schistosomiasis as a tool for future HIV prevention

    DEFF Research Database (Denmark)

    Stecher, Chalotte Willemann; Kallestrup, Per; Kjetland, Eyrun Floerecke

    2015-01-01

    OBJECTIVES: Male genital schistosomiasis (MGS) is a neglected manifestation of Schistosoma haematobium infection with ignored implications on reproductive health and a differential diagnosis to sexually transmitted infections in endemic regions. MGS may have associations with HIV transmission...... and acquisition, and treatment could be a neglected chance of HIV prevention. This review summarizes current knowledge on epidemiology, clinical manifestations, diagnosis and treatment of MGS as a hypothesized risk factor for HIV transmission. Future research areas of global interest are suggested. METHODS: Pub...... association between MGS and HIV are urgently needed. Furthermore, field diagnostic tools should be developed and future mass treatment programs should include adults to reduce morbidity and prevent HIV acquisition. SYSTEMATIC REVIEW REGISTRATION NUMBER: CRD42015016252....

  13. Revealing flow behaviors of metallic glass based on activation of flow units

    Energy Technology Data Exchange (ETDEWEB)

    Ge, T. P.; Wang, W. H.; Bai, H. Y., E-mail: hybai@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2016-05-28

    Atomic level flow plays a critical role in the mechanical behavior of metallic glass (MG) while the connection between the flow and the heterogeneous microstructure of the glass remains unclear. We describe the heterogeneity of MGs as the elastic matrix with “inclusions” of nano-scale liquid-like flow units, and the plastic flow behavior of MGs is considered to be accommodated by the flow units. We show that the model can explain the various deformation behaviors, the transformation from inhomogeneous deformation to homogeneous flow upon strain rate or temperature, and the deformation map in MGs, which might provide insights into the flow mechanisms in glasses and inspiration for improving the plasticity of MGs.

  14. Declines in arrestin and rhodopsin in the macula with progression of age-related macular degeneration.

    Science.gov (United States)

    Ethen, Cheryl M; Feng, Xiao; Olsen, Timothy W; Ferrington, Deborah A

    2005-03-01

    Biochemical analysis of age-related macular degeneration (AMD) at distinct stages of the disease will help further understanding of the molecular events associated with disease progression. This study was conducted to determine the ability of a new grading system for eye bank eyes, the Minnesota Grading System (MGS), to discern distinct stages of AMD so that retinal region-specific changes in rod photoreceptor protein expression from donors could be determined. Donor eyes were assigned to a specific level of AMD by using the MGS. Expression of the rod photoreceptor proteins rhodopsin and arrestin was evaluated by Western immunoblot analysis in the macular and peripheral regions of the neurosensory retina from donors at different stages of AMD. A significant linear decline in both arrestin and rhodopsin content correlated with progressive MGS levels in the macula. In contrast, the peripheral region showed no significant correlation between MGS level and the content of either protein. The statistically significant relationship between decreasing macular rod photoreceptor proteins and progressive MGS levels of AMD demonstrates the utility of the clinically based MGS to correspond with specific protein changes found at known, progressive stages of degeneration. Future biochemical analysis of clinically characterized donor eyes will further understanding of the pathobiochemistry of AMD.

  15. Power Talk

    DEFF Research Database (Denmark)

    Liu, Hongpeng; Yang, Yongheng; Loh, Poh Chiang

    2016-01-01

    In this paper, a novel communication strategy called Power Talk is introduced to realize the power line communication among the Voltage Source Converters (VSC) of DC MicroGrids (MGs). Each VSC transmits information by changing the control parameters, and receives information by observing the local...

  16. Simulated orbits of heavy planetary ions at Mars for different IMF configurations

    Science.gov (United States)

    Curry, Shannon; Luhmann, Janet; Livi, Roberto; Hara, Takuya; Dong, Chuanfei; Ma, Yingjuan; McFadden, James; Bougher, Stephen

    2014-11-01

    We present simulated detections of O+, O2+ and CO2+ ions at Mars along a virtual orbit in the Mars space environment. Planetary pick-up ions are formed through the direct interaction of the solar wind with the neutral upper atmosphere, causing the newly created ions to be picked up and accelerated by the background convective electric field. Because previous missions such as Mars Global Surveyor (MGS) and Mars Express (MEX) have not been able to measure the interplanetary magnetic field (IMF) components simultaneously with plasma measurements, the response of heavy planetary pick-up ions to changes in the IMF has not been well characterized. Using a steady-state multi-species MHD model to provide the background electric and magnetic fields, the Mars Test Particle (MTP) simulation can trace each of these particles along field lines in near-Mars space and construct virtual ion detections from a spacecraft orbit. Specifically, we will present energy-time spectrograms and velocity space distributions (VSDs) for a selection of orbits during different IMF configurations and solar cycle conditions. These simulated orbits have broader implications for how to measure ion escape. Using individual particle traces, the origin and trajectories of different ion populations can be analyzed in order to assess how and where they contribute to the total atmospheric escape rate, which is a major objective of the upcoming MAVEN mission.

  17. Stationary Planetary Waves in the Mars Winter Atmosphere as seen by the Radio Science Experiment MaRS on Mars Express

    Science.gov (United States)

    Tellmann, Silvia; Pätzold, Martin; Häusler, Bernd; Tyler, Leonard G.; Hinson, David P.

    2015-11-01

    Stationary (Rossby) Waves are excited by the interaction of the zonally varying topography with the strong eastward winter jets. They lead to distinctive longitudinal temperature variations which contribute significantly to the asymmetry of the seasonal polar CO2 ice caps and are also important for the dust redistribution in the planetary atmosphere.Radio Science profiles from the Mars Express Radio Science Experiment MaRS at northern and southern high latitudes are used to gain insight into winter stationary wave structures on both hemispheres.Mars Global Surveyor (MGS) radio occultation measurements from the same season and year with their exceptionally good longitudinal and temporal coverage can be used to estimate the influence of transient eddies. Transient waves are especially important in the northern winter hemisphere.Wave number 2 stationary waves, driven by topography, are dominant in the northern winter latitudes while the wave number 1 wave is the most significant wave number during southern winter. The wave amplitudes peak around winter solstice on both hemispheres.Radio occultation measurements provide the unique opportunity to determine simultaneous measurements of temperature and geopotential height structures. Assuming geostrophic balance, these measurements can be used to determine meridional winds and eddy heat fluxes which provide further insight into the contribution of stationary waves to the heat exchange between the poles and the lower latitudes.

  18. Morning Glory Syndrome with Carotid and Middle Cerebral Artery Vasculopathy.

    Science.gov (United States)

    Nezzar, Hachemi; Mbekeani, Joyce N; Dalens, Helen

    2015-12-01

    To report a case of incidental asymptomatic atypical morning glory syndrome (MGS) with concomitant ipsilateral carotid and middle cerebral dysgenesis. A 6-year-old child was discovered to have incidental findings of MGS, with atypia. All visual functions were normal including vision and stereopsis. Neuroimaging revealed ipsilateral carotid and middle cerebral vascular narrowing without associated collateral vessels or cerebral ischemia commonly seen in Moyamoya disease. Subsequent annual examinations have been stable, without signs of progression. This case demonstrates disparity between structural aberrations and final visual and neurological function and reinforces the association between MGS and intracranial vascular disruption. Full ancillary ophthalmic and neuroimaging studies should be performed in all patients with MGS with interval reassessments, even when the patient is asymptomatic and functionally intact.

  19. The transition to efficiency in minority games

    International Nuclear Information System (INIS)

    Galla, Tobias; De Martino, Andrea

    2008-01-01

    The existence of a phase transition with diverging susceptibility in batch minority games (MGs) is the mark of informationally efficient regimes and is linked to the specifics of the agents' learning rules. Here, we study how the standard scenario is affected in a mixed population game in which agents with the 'optimal' learning rule (i.e. the one leading to efficiency) coexist with those whose adaptive dynamics is sub-optimal. Our generic finding is that any non-vanishing intensive fraction of optimal agents guarantees the existence of an efficient phase. Specifically, we calculate the dependence of the critical point on the fraction q of 'optimal' agents focusing our analysis on three cases: MGs with market impact correction, grand-canonical MGs and MGs with heterogeneous comfort levels

  20. NADPH-diaphorase expression in the Meibomian glands of rat palpebra in postnatal development

    Directory of Open Access Journals (Sweden)

    D. Kluchova

    2010-11-01

    Full Text Available In the current study, we aimed at investigating the presence of nitric oxide synthase (NOS positive nerve fibers in rat meibomian glands (MGs at various stages of development. There is good evidence to suggest that nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d is a surrogate for neuronal nitric oxide synthase (NOS. Sections of the central, upper eyelids of Wistar rats were processed histochemically for NADPH-d to investigate the presence and distribution of NOS-positive nerve fibers at the following time points: day 1 and weeks 1, 2 and 3 post partum, and in adult controls. At day 1, MG acini were lightly stained and located at a distance from the mucosal border. Vessels were accompanied by intensely stained NADPH-d positive nerve fibers. At the week 1 time point, both the vessels and the NADPH-d positive fibers were still present, but less numerous. MGs were now closer to the mucosa, so that the submucosa was thinner. The acini were mostly pale but occasionally darker. At week 3, there were fewer blood vessels in both the submucosa and within the septa. Darker acini were more common than lightly stained acini. NADPH-d positive dots were observed in the vicinity of the MGs. At the week 3 time point, MGs were adjacent to the mucosal border and stained more intensely than at earlier times; almost all acini were stained. The microscopic appearances were almost identical with those of adult palpebra. Submucosal and septal blood vessels and NADPH-d positive nerve fibers were less numerous. NADPH-d histochemical staining confirmed differences in the density of stained nerve fibers at different developmental stages. The greatest density of NADPH-d -positive nerve fibers occurred in 1-day-old rats whereas they were less numerous in adult rat eyelids. Nerves innervating MGs utilize nitric oxide (NO as a neurotransmitter mostly in early developmental stages and this need thereafter decreases and stabilizes at 3 weeks postnatally.

  1. Meibomian gland dysfunction patients with novel Sjögren’s syndrome biomarkers benefit significantly from a single vectored thermal pulsation procedure: a retrospective analysis

    Directory of Open Access Journals (Sweden)

    Epitropoulos AT

    2017-04-01

    Full Text Available Alice T Epitropoulos,1,2 Krysta Goslin,2 Raman Bedi,3 Caroline A Blackie4 1Ophthalmic Surgeons and Consultants of Ohio, The Eye Center of Columbus, 2The Ohio State University Wexner Medical Center, Department of Ophthalmology, Columbus, OH, USA; 3Iris Advanced Eye Centre, Chandigarh, India; 4TearScience Inc., Morrisville, NC, USA Purpose: To measure the effects from a single vectored thermal pulsation treatment of the meibomian glands on dry eye signs and symptoms in patients who tested positively versus negatively for novel Sjögren’s syndrome (SS biomarkers. Methods: The retrospective study included the deidentified data of 102 eyes of 59 patients with dry eye and meibomian gland dysfunction (MGD, who were also tested for novel biomarkers for SS and underwent a single 12-minute LipiFlow thermal pulsation procedure. All patients were already being treated with individualized dry eye therapy but remained symptomatic. Meibomian gland secretion (MGS scores, Standard Patient Evaluation of Eye Dryness (SPEED questionnaire scores and tear breakup times (TBUTs before and 8 weeks after thermal pulsation treatment were analyzed. Results: Twenty-three patients tested positive for novel biomarkers of SS and 36 patients tested negative. At baseline, MGS, SPEED and TBUT of both SS-positive and SS-negative patients were equivalent. At 8 weeks’ post-treatment, mean MGS score, SPEED and TBUT were 13.0±7.8, 12.5±6.8 and 9.6±4.6, respectively, in SS-positive patients and 15.9±7.9, 10.0±6.3 and 8.3±4.6, respectively, in SS-negative patients (P<0.001. While the post-treatment MGS was significantly better in SS-negative patients than SS-positive (P=0.021, no significant difference between post-treatment SPEED and TBUT was observed between the two groups (P>0.05. Conclusion: LipiFlow treatment in MGD patients who were SS-positive for novel biomarkers of SS demonstrated improvement in signs and symptoms of dry eye. While improvement in MGS scores in SS

  2. Parahippocampal Involvement in Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis: A Proof of Concept from Memory-Guided Saccades

    Directory of Open Access Journals (Sweden)

    Silvia Colnaghi

    2017-11-01

    Full Text Available ObjectiveMesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS may involve extrahippocampal areas of structural damage and dysfunction. The accuracy of medium-term spatial memory can be tested by memory-guided saccades (MGS to evaluate a functional impairment of the parahippocampal cortex (PHC, while voxel-based morphometry (VBM analysis can be used to detect a structural damage of the latter region.MethodsMGS with 3- and 30-s memorization delays were compared between 7 patients affected by right MTLE-HS (r-MTLE-HS, 6 patients affected by left MTLE-HS, and 13 healthy controls. The same subjects underwent brain MRI for a VBM analysis. Correlation analysis was performed between the results of VBM and MGS and with patients’ clinical data.ResultsRight MTLE-HS patients showed impaired accuracy of leftward MGS with a 30-s memorization delay; their gray-matter volume was reduced in the right hippocampus and inferior temporal gyrus, and bilaterally in the cerebellum. Left MTLE-HS patients had normal MGS accuracy; their gray-matter volume was reduced in the left hippocampus, in the right-inferior temporal gyrus and corpus callosus, and bilaterally in the insular cortex and in the cerebellum. The difference between right and left parahippocampal volumes correlated with MGS accuracy, while right and left hippocampal volumes did not. Hippocampal and parahippocampal volume did not correlate with clinical variables such as febrile seizures, age at disease onset, disease duration, and seizure frequency.ConclusionMGS abnormalities suggested the functional involvement of the right PHC in patients with r-MTLE-HS, supporting a right lateralization of spatial memory control and showing a relation between functional impairment and degree of atrophy.

  3. Characterization of overwintering sites of the invasive brown marmorated stink bug in natural landscapes using human surveyors and detector canines.

    Directory of Open Access Journals (Sweden)

    Doo-Hyung Lee

    Full Text Available Halyomorpha halys is an invasive species from Asia causing major economic losses in agricultural production in the mid-Atlantic region of the United States. Unlike other crop pests, H. halys is also well-known for nuisance problems in urban, suburban, and rural areas, as massive numbers of adults often invade human-made structures to overwinter inside protected environments. Research efforts have focused on populations in human-made structures while overwintering ecology of H. halys in natural landscapes is virtually unknown. We explored forested landscapes in the mid-Atlantic region to locate and characterize natural overwintering structures used by H. halys. We also evaluated the use of detector canines to locate overwintering H. halys to enhance the accuracy and efficiency of surveys. From these studies, we indentified shared characteristics of overwintering sites used by H. halys in natural landscapes. Overwintering H. halys were recovered from dry crevices in dead, standing trees with thick bark, particularly oak (Quercus spp. and locust (Robinia spp.; these characteristics were shared by 11.8% of all dead trees in surveyed landscapes. For trees with favorable characteristics, we sampled ∼20% of the total above-ground tree area and recovered 5.9 adults per tree from the trees with H. halys present. Two detector canines were successfully trained to recognize and detect the odor of adult H. halys yielding >84% accuracy in laboratory and semi-field trials. Detector canines also found overwintering H. halys under field conditions. In particular, overwintering H. halys were recovered only from dead trees that yielded positive indications from the canines and shared key tree characteristics established by human surveyors. The identified characteristics of natural overwintering sites of H. halys will serve as baseline information to establish crop economic risk levels posed by overwintering populations, and accordingly develop sustainable

  4. A comparison between anisotropic analytical and multigrid superposition dose calculation algorithms in radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Wu, Vincent W.C.; Tse, Teddy K.H.; Ho, Cola L.M.; Yeung, Eric C.Y.

    2013-01-01

    Monte Carlo (MC) simulation is currently the most accurate dose calculation algorithm in radiotherapy planning but requires relatively long processing time. Faster model-based algorithms such as the anisotropic analytical algorithm (AAA) by the Eclipse treatment planning system and multigrid superposition (MGS) by the XiO treatment planning system are 2 commonly used algorithms. This study compared AAA and MGS against MC, as the gold standard, on brain, nasopharynx, lung, and prostate cancer patients. Computed tomography of 6 patients of each cancer type was used. The same hypothetical treatment plan using the same machine and treatment prescription was computed for each case by each planning system using their respective dose calculation algorithm. The doses at reference points including (1) soft tissues only, (2) bones only, (3) air cavities only, (4) soft tissue-bone boundary (Soft/Bone), (5) soft tissue-air boundary (Soft/Air), and (6) bone-air boundary (Bone/Air), were measured and compared using the mean absolute percentage error (MAPE), which was a function of the percentage dose deviations from MC. Besides, the computation time of each treatment plan was recorded and compared. The MAPEs of MGS were significantly lower than AAA in all types of cancers (p<0.001). With regards to body density combinations, the MAPE of AAA ranged from 1.8% (soft tissue) to 4.9% (Bone/Air), whereas that of MGS from 1.6% (air cavities) to 2.9% (Soft/Bone). The MAPEs of MGS (2.6%±2.1) were significantly lower than that of AAA (3.7%±2.5) in all tissue density combinations (p<0.001). The mean computation time of AAA for all treatment plans was significantly lower than that of the MGS (p<0.001). Both AAA and MGS algorithms demonstrated dose deviations of less than 4.0% in most clinical cases and their performance was better in homogeneous tissues than at tissue boundaries. In general, MGS demonstrated relatively smaller dose deviations than AAA but required longer computation time

  5. Implementing a Science-driven Mars Exploration Program

    Science.gov (United States)

    Garvin, J. B.

    2001-12-01

    NASA's newly restructured Mars Exploration Program (MEP) was developed on the basis of the goals, objectives, investigations, and prioritizations established by the Mars Exploration Payload Analysis Group (as summarized previously by Greeley et al., 2001). The underlying scientific strategy is linked to common threads which include the many roles water has played on and within Mars as a "system". The implementation strategy that has been adopted relies heavily on an ever-sharpening program of reconnaissance, beginning with the legacy of the Mars Global Surveyor, continuing with the multispectral and compositional observations of the Mars Odyssey orbiter, and extending to a first step in surface-based reconnaissance with the 2003 Mars Exploration Rovers. The results of MGS and Odyssey will serve to focus the trade space of localities where the record, for example, of persistent surface water may have been preserved in a mineralogical sense. The 2005 Mars Reconnaissance Orbiter will further downselect the subset of sites on Mars where evidence of depositional patterns and aqueous mineralogies (i.e., diagenetic minerals) are most striking at scales as fine as tens to hundreds of meters. Reconnaissance will move to the surface and shallow subsurface in 2007 with the Mars "Smart Lander" (MSL), at which time an extensive array of mobile scientific exploration tools will be used to examine a locality at 10km traverse scales, ultimately asking scientific questions which can be classed as paleobiological (i.e., life inference). Further orbital reconnaissance may be undertaken in 2009, perhaps involving targeted multi-wavelength SAR imaging, in anticipation of a precisely targeted Mars Sample Return mission as early as 2011. This sequence of core program MEP missions will be amplified by the selection of PI-led SCOUT missions, starting in 2007, and continuing every other Mars launch opportunity.

  6. Human performance in radiological survey scanning

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W.S. [Brookhaven National Lab., Upton, NY (United States); Abelquist, E.W. [Oak Ridge Inst. for Science and Education, TN (United States)

    1998-03-01

    The probability of detecting residual contamination in the field using portable radiological survey instruments depends not only on the sensitivity of the instrumentation used in scanning, but also on the surveyor`s performance. This report provides a basis for taking human performance into account in determining the minimum level of activity detectable by scanning. A theoretical framework was developed (based on signal detection theory) which allows influences on surveyors to be anticipated and understood, and supports a quantitative assessment of performance. The performance of surveyors under controlled yet realistic field conditions was examined to gain insight into the task and to develop means of quantifying performance. Then, their performance was assessed under laboratory conditions to quantify more precisely their ability to make the required discriminations. The information was used to characterize surveyors` performance in the scanning task and to provide a basis for predicting levels of radioactivity that are likely to be detectable under various conditions by surveyors using portable survey instruments.

  7. Generating functional analysis of minority games with inner product strategy definitions

    Science.gov (United States)

    Coolen, A. C. C.; Shayeghi, N.

    2008-08-01

    We use generating functional methods to solve the so-called inner product versions of the minority game (MG), with fake and/or real market histories, by generalizing the theory developed recently for look-up table MGs with real histories. The phase diagrams of the look-up table and inner product MG versions are generally found to be identical, with the exception of inner product MGs where histories are sampled linearly, which are found to be structurally critical. However, we encounter interesting differences both in the theory (where the role of the history frequency distribution in look-up table MGs is taken over by the eigenvalue spectrum of a history covariance matrix in inner product MGs) and in the static and dynamic phenomenology of the models. Our theoretical predictions are supported by numerical simulations.

  8. Generating functional analysis of minority games with inner product strategy definitions

    Energy Technology Data Exchange (ETDEWEB)

    Coolen, A C C; Shayeghi, N [Department of Mathematics, King' s College London, The Strand, London WC2R 2LS (United Kingdom)], E-mail: ton.coolen@kcl.ac.uk, E-mail: nima@mth.kcl.ac.uk

    2008-08-15

    We use generating functional methods to solve the so-called inner product versions of the minority game (MG), with fake and/or real market histories, by generalizing the theory developed recently for look-up table MGs with real histories. The phase diagrams of the look-up table and inner product MG versions are generally found to be identical, with the exception of inner product MGs where histories are sampled linearly, which are found to be structurally critical. However, we encounter interesting differences both in the theory (where the role of the history frequency distribution in look-up table MGs is taken over by the eigenvalue spectrum of a history covariance matrix in inner product MGs) and in the static and dynamic phenomenology of the models. Our theoretical predictions are supported by numerical simulations.

  9. Hierarchical Control for Optimal and Distributed Operation of Microgrid Systems

    DEFF Research Database (Denmark)

    Meng, Lexuan

    manages the power flow with external grids, while the economic and optimal operation of MGs is not guaranteed by applying the existing schemes. Accordingly, this project dedicates to the study of real-time optimization methods for MGs, including the review of optimization algorithms, system level...... mathematical modeling, and the implementation of real-time optimization into existing hierarchical control schemes. Efficiency enhancement in DC MGs and optimal unbalance compensation in AC MGs are taken as the optimization objectives in this project. Necessary system dynamic modeling and stability analysis......, a discrete-time domain modeling method is proposed to establish an accurate system level model. Taking into account the different sampling times of real world plant, digital controller and communication devices, the system is modeled with these three parts separately, and with full consideration...

  10. Generating functional analysis of minority games with inner product strategy definitions

    International Nuclear Information System (INIS)

    Coolen, A C C; Shayeghi, N

    2008-01-01

    We use generating functional methods to solve the so-called inner product versions of the minority game (MG), with fake and/or real market histories, by generalizing the theory developed recently for look-up table MGs with real histories. The phase diagrams of the look-up table and inner product MG versions are generally found to be identical, with the exception of inner product MGs where histories are sampled linearly, which are found to be structurally critical. However, we encounter interesting differences both in the theory (where the role of the history frequency distribution in look-up table MGs is taken over by the eigenvalue spectrum of a history covariance matrix in inner product MGs) and in the static and dynamic phenomenology of the models. Our theoretical predictions are supported by numerical simulations

  11. Assessment of Mars Atmospheric Temperature Retrievals from the Thermal Emission Spectrometer Radiances

    Science.gov (United States)

    Hoffman, Matthew J.; Eluszkiewicz, Janusz; Weisenstein, Deborah; Uymin, Gennady; Moncet, Jean-Luc

    2012-01-01

    Motivated by the needs of Mars data assimilation. particularly quantification of measurement errors and generation of averaging kernels. we have evaluated atmospheric temperature retrievals from Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) radiances. Multiple sets of retrievals have been considered in this study; (1) retrievals available from the Planetary Data System (PDS), (2) retrievals based on variants of the retrieval algorithm used to generate the PDS retrievals, and (3) retrievals produced using the Mars 1-Dimensional Retrieval (M1R) algorithm based on the Optimal Spectral Sampling (OSS ) forward model. The retrieved temperature profiles are compared to the MGS Radio Science (RS) temperature profiles. For the samples tested, the M1R temperature profiles can be made to agree within 2 K with the RS temperature profiles, but only after tuning the prior and error statistics. Use of a global prior that does not take into account the seasonal dependence leads errors of up 6 K. In polar samples. errors relative to the RS temperature profiles are even larger. In these samples, the PDS temperature profiles also exhibit a poor fit with RS temperatures. This fit is worse than reported in previous studies, indicating that the lack of fit is due to a bias correction to TES radiances implemented after 2004. To explain the differences between the PDS and Ml R temperatures, the algorithms are compared directly, with the OSS forward model inserted into the PDS algorithm. Factors such as the filtering parameter, the use of linear versus nonlinear constrained inversion, and the choice of the forward model, are found to contribute heavily to the differences in the temperature profiles retrieved in the polar regions, resulting in uncertainties of up to 6 K. Even outside the poles, changes in the a priori statistics result in different profile shapes which all fit the radiances within the specified error. The importance of the a priori statistics prevents

  12. Comparison of Anti-Obesity Effect between Two Types of Syrup Containing Rare Sugars in Wistar Rats.

    Science.gov (United States)

    Ochiai, Masaru; Misaki, Kohei; Yamada, Takako; Iida, Tetsuo; Okuma, Kazuhiro; Matsuo, Tatsuhiro

    2017-01-01

    D-Allulose-containing rare sugar sweeteners have been categorized into two types, rare sugar syrup (RSS), consisting of 4 rare monosaccharides, and modified glucose syrup (MGS), rich in D-allulose, which was previously referred to D-psicose. The anti-obesity effect of RSS and D-allulose has been already clarified, but that of rare monosaccharides other than D-allulose in RSS has not yet been well understood. Here, we investigated and compared the anti-obesity effect of RSS and MGS in rats. Male Wistar rats were divided into 4 dietary groups: a high-sucrose control diet group (S), a high-fructose corn syrup diet group (HFCS), an RSS diet group (RSS), and an MGS diet group (MGS). RSS significantly suppressed abdominal adipose tissue weight and total body fat accumulation in comparison to sucrose. On the other hand, MGS reduced body weight gain, but not abdominal fat accumulation, relative to sucrose. The weight of the liver and kidneys was significantly higher in the RSS and MGS groups than in the S and HFCS groups, but serum biochemical parameters and hepatic lipids contents were not significantly different among the groups. The present study shows that two types of D-allulose-containing rare sugar sweeteners can suppress body fat accumulation or weight gain in a different manner and that RSS could be used as more effective sweeteners in place of sucrose and HFCS to maintain healthy body weight.

  13. Monoglyceride lipase as a drug target: At the crossroads of arachidonic acid metabolism and endocannabinoid signaling.

    Science.gov (United States)

    Grabner, Gernot F; Zimmermann, Robert; Schicho, Rudolf; Taschler, Ulrike

    2017-07-01

    Monoglyerides (MGs) are short-lived, intermediary lipids deriving from the degradation of phospho- and neutral lipids, and monoglyceride lipase (MGL), also designated as monoacylglycerol lipase (MAGL), is the major enzyme catalyzing the hydrolysis of MGs into glycerol and fatty acids. This distinct function enables MGL to regulate a number of physiological and pathophysiological processes since both MGs and fatty acids can act as signaling lipids or precursors thereof. The most prominent MG species acting as signaling lipid is 2-arachidonoyl glycerol (2-AG) which is the most abundant endogenous agonist of cannabinoid receptors in the body. Importantly, recent observations demonstrate that 2-AG represents a quantitatively important source for arachidonic acid, the precursor of prostaglandins and other inflammatory mediators. Accordingly, MGL-mediated 2-AG degradation affects lipid signaling by cannabinoid receptor-dependent and independent mechanisms. Recent genetic and pharmacological studies gave important insights into MGL's role in (patho-)physiological processes, and the enzyme is now considered as a promising drug target for a number of disorders including cancer, neurodegenerative and inflammatory diseases. This review summarizes the basics of MG (2-AG) metabolism and provides an overview on the therapeutic potential of MGL. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. An overview on the conventional and nonconventional methods for manufacturing the metallic glasses

    Directory of Open Access Journals (Sweden)

    Axinte Eugen

    2017-01-01

    Full Text Available Metallic glasses (MGs, first discovered in 1959 at Caltech are currently among the most studied metallic materials. MGs called also glassy metals, amorphous metals, liquid metals, are considered to be among the materials of the future. The “classic” methods for industrialization of MGs are : end-casting in copper molds and protected environment, die forging , atomization for obtaining MG powder ,selective laser melting , imprinting in molds, thermoplastic shaping in the super-cooled temperature region. These methods are suitable for producing high value-added precision components but the problems still exists: expensive tools, limited lifetime of tools and the occurring of crystallization. Actually methods (thermoplastic shaping, casting and die forging are limited by the low flexibility of production and by higher costs of tools and accessories. More suitable methods are greatly desired to machine MGs for their wider applications.

  15. Prefiriendo siempre á los agrimensores científicos". Discriminación en la medición y el reparto de reguardos indígenas en la altiplano cundiboyacense, 1821-1854

    Directory of Open Access Journals (Sweden)

    Lina Del Castillo

    2006-12-01

    Full Text Available This article examines the process of privatization of indigenous reservations in New Granada and argues that the process was mired in confict. The article demonstrates how ethnic and gender discrimination sparked confict as attempts were made to privatize indigenous reservations. The focus of the struggles for control over the privatization process was the surveyor: he who had the power to name the surveyor could -in large part- control how the privatized land parcels would be distributed. By naming surveyors trained in the national Military School, the governors in Bogotá consolidated their political power over privatization, legitimated a process that fomented ethnic and gender discrimination, and promoted the reputations of surveyors trained in the Military School as neutral, dependable experts, despite the mistakes these surveyors also committed.

  16. Evaluating health worker performance in Benin using the simulated client method with real children

    Directory of Open Access Journals (Sweden)

    Rowe Alexander K

    2012-10-01

    Full Text Available Abstract Background The simulated client (SC method for evaluating health worker performance utilizes surveyors who pose as patients to make surreptitious observations during consultations. Compared to conspicuous observation (CO by surveyors, which is commonly done in developing countries, SC data better reflect usual health worker practices. This information is important because CO can cause performance to be better than usual. Despite this advantage of SCs, the method’s full potential has not been realized for evaluating performance for pediatric illnesses because real children have not been utilized as SCs. Previous SC studies used scenarios of ill children that were not actually brought to health workers. During a trial that evaluated a quality improvement intervention in Benin (the Integrated Management of Childhood Illness [IMCI] strategy, we conducted an SC survey with adult caretakers as surveyors and real children to evaluate the feasibility of this approach and used the results to assess the validity of CO. Methods We conducted an SC survey and a CO survey (one right after the other of health workers in the same 55 health facilities. A detailed description of the SC survey process was produced. Results of the two surveys were compared for 27 performance indicators using logistic regression modeling. Results SC and CO surveyors observed 54 and 185 consultations, respectively. No serious problems occurred during the SC survey. Performance levels measured by CO were moderately higher than those measured by SCs (median CO – SC difference = 16.4 percentage-points. Survey differences were sometimes much greater for IMCI-trained health workers (median difference = 29.7 percentage-points than for workers without IMCI training (median difference = 3.1 percentage-points. Conclusion SC surveys can be done safely with real children if appropriate precautions are taken. CO can introduce moderately large positive biases, and these biases might

  17. Mars Surveyor Program '01 Mars Environmental Compatibility Assessment wet chemistry lab: a sensor array for chemical analysis of the Martian soil

    Science.gov (United States)

    Kounaves, Samuel P.; Lukow, Stefan R.; Comeau, Brian P.; Hecht, Michael H.; Grannan-Feldman, Sabrina M.; Manatt, Ken; West, Steven J.; Wen, Xiaowen; Frant, Martin; Gillette, Tim

    2003-01-01

    The Mars Environmental Compatibility Assessment (MECA) instrument was designed, built, and flight qualified for the now canceled MSP (Mars Surveyor Program) '01 Lander. The MECA package consisted of a microscope, electrometer, material patch plates, and a wet chemistry laboratory (WCL). The primary goal of MECA was to analyze the Martian soil (regolith) for possible hazards to future astronauts and to provide a better understanding of Martian regolith geochemistry. The purpose of the WCL was to analyze for a range of soluble ionic chemical species and electrochemical parameters. The heart of the WCL was a sensor array of electrochemically based ion-selective electrodes (ISE). After 20 months storage at -23 degrees C and subsequent extended freeze/thawing cycles, WCL sensors were evaluated to determine both their physical durability and analytical responses. A fractional factorial calibration of the sensors was used to obtain slope, intercept, and all necessary selectivity coefficients simultaneously for selected ISEs. This calibration was used to model five cation and three anion sensors. These data were subsequently used to determine concentrations of several ions in two soil leachate simulants (based on terrestrial seawater and hypothesized Mars brine) and four actual soil samples. The WCL results were compared to simulant and soil samples using ion chromatography and inductively coupled plasma optical emission spectroscopy. The results showed that flight qualification and prolonged low-temperature storage conditions had minimal effects on the sensors. In addition, the analytical optimization method provided quantitative and qualitative data that could be used to accurately identify the chemical composition of the simulants and soils. The WCL has the ability to provide data that can be used to "read" the chemical, geological, and climatic history of Mars, as well as the potential habitability of its regolith.

  18. Quality control of measurements made on fixed-area sample plots

    Science.gov (United States)

    Ola Lindgren

    2000-01-01

    The paper describes results from a large program for quality control of forest measurements. The performance of 87 surveyors was evaluated. Tree heights were usually measured well, whereas the counting of tree-rings on increment cores was a source of considerable bias for many surveyors. During tree count on sample plots, many surveyors had a tendency to forget trees,...

  19. Earth's Largest Terrestrial Landslide (The Markagunt Gravity Slide of Southwest Utah): Insights from the Catastrophic Collapse of a Volcanic Field

    Science.gov (United States)

    Hacker, D. B.; Biek, R. F.; Rowley, P. D.

    2015-12-01

    The newly discovered Miocene Markagunt gravity slide (MGS; Utah, USA) represents the largest volcanic landslide structure on Earth. Recent geologic mapping of the MGS indicates that it was a large contiguous volcanic sheet of allochthonous andesitic mudflow breccias and lava flows, volcaniclastic rocks, and intertonguing regional ash-flow tuffs that blanketed an area of at least 5000 km2 with an estimated volume of ~3000 km3. From its breakaway zone in the Tushar and Mineral Mountains to its southern limits, the MGS is over 95 km long and at least 65 km wide. The MGS consists of four distinct structural segments: 1) a high-angle breakaway segment, 2) a bedding-plane segment, ~60 km long and ~65 km wide, typically located within the volcaniclastic Eocene-Oligocene Brian Head Formation, 3) a ramp segment ~1-2 km wide where the slide cuts upsection, and 4) a former land surface segment where the upper-plate moved at least 35 km over the Miocene landscape. The presence of basal and lateral cataclastic breccias, clastic dikes, jigsaw puzzle fracturing, internal shears, pseudotachylytes, and the overall geometry of the MGS show that it represents a single catastrophic emplacement event. The MGS represents gravitationally induced collapse of the southwest sector of the Oligocene to Miocene Marysvale volcanic field. We suggest that continuous growth of the Marysvale volcanic field, loading more volcanic rocks on a structurally weak Brian Head basement, created conditions necessary for gravity sliding. In addition, inflation of the volcanic pile due to multiple magmatic intrusions tilted the strata gently southward, inducing lateral spreading of the sub-volcanic rocks prior to failure. Although similar smaller-scale failures have been recognized from individual volcanoes, the MGS represents a new class of low frequency but high impact hazards associated with catastrophic sector collapse of large volcanic fields containing multiple volcanoes. The relationship of the MGS to

  20. Two new modified Gauss-Seidel methods for linear system with M-matrices

    Science.gov (United States)

    Zheng, Bing; Miao, Shu-Xin

    2009-12-01

    In 2002, H. Kotakemori et al. proposed the modified Gauss-Seidel (MGS) method for solving the linear system with the preconditioner [H. Kotakemori, K. Harada, M. Morimoto, H. Niki, A comparison theorem for the iterative method with the preconditioner () J. Comput. Appl. Math. 145 (2002) 373-378]. Since this preconditioner is constructed by only the largest element on each row of the upper triangular part of the coefficient matrix, the preconditioning effect is not observed on the nth row. In the present paper, to deal with this drawback, we propose two new preconditioners. The convergence and comparison theorems of the modified Gauss-Seidel methods with these two preconditioners for solving the linear system are established. The convergence rates of the new proposed preconditioned methods are compared. In addition, numerical experiments are used to show the effectiveness of the new MGS methods.

  1. Low specific-grinding energy machining of ceramics by a laser dressed diamond grinding stone

    International Nuclear Information System (INIS)

    Jodan, K.; Matsumaru, K.; Ishizaki, K.

    2003-01-01

    A laser dressing is an effective dressing method to accomplish efficient ceramic grinding. Since laser dressing achieves protrusion heights of abrasive-grains without grain dislodgment, the number of abrasive-grains in a laser dressed grinding stone (LGS) is higher than that in a mechanically dressed grinding stone (MGS), remaining the initial grain distribution. Thus, the LGS contains higher number of effective cutting edges, and forms higher number of ground grooves on a ground surface than the MGS. Consequently, the LGS can achieve lower specific grinding energy than the MGS. Copyright (2003) AD-TECH - International Foundation for the Advancement of Technology Ltd

  2. Non-localized deformation in Cu−Zr multi-layer amorphous films under tension

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, C. [International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, State Key Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Zhang, H. [International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, State Key Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Cao, Q.P.; Wang, X.D. [International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, State Key Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Zhang, D.X. [State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027 (China); Hu, J.W. [Hangzhou Workers Amateur University, Hangzhou 310027 (China); Liaw, P.K. [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996 (United States); Jiang, J.Z., E-mail: jiangjz@zju.edu.cn [International Center for New-Structured Materials (ICNSM), Laboratory of New-Structured Materials, State Key Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

    2016-09-05

    In metallic glasses (MGs), plastic deformation at room temperature is dominated by highly localized shear bands. Here we report the non-localized deformation under tension in Cu−Zr multi-layer MGs with a pure amorphous structure using large-scale atomistic simulations. It is demonstrated that amorphous samples with high layer numbers, composed of Cu{sub 64}Zr{sub 36} and Cu{sub 40}Zr{sub 60}, or Cu{sub 64}Zr{sub 36} and Cu{sub 50}Zr{sub 50}, present obviously non-localized deformation behavior. We reveal that the deformation behavior of the multi-layer-structured MG films is related but not determined by the deformation behavior of the composed individual layers. The criterion for the deformation mode change for MGs with a pure amorphous structure, in generally, was suggested, i.e., the competition between the elastic-energy density stored and the energy density needed for forming one mature shear band in MGs. Our results provide a promising strategy for designing tensile ductile MGs with a pure amorphous structure at room temperature. - Highlights: • Tensile deformation behaviors in multi-layer MG films. • Films with high layer numbers confirmed with a non-localized deformation behavior. • The deformation mode is reasonably controlled by whether U{sub p} larger than U{sub SB.}.

  3. Smart transactive energy framework in grid-connected multiple home microgrids under independent and coalition operations

    DEFF Research Database (Denmark)

    Marzband, Mousa; Azarinejadian, Fatemeh; Savaghebi, Mehdi

    2018-01-01

    This paper presents a smart Transactive energy (TE) framework in which home microgrids (H-MGs) can collaborate with each other in a multiple H-MG system by forming coalitions for gaining competitiveness in the market. Profit allocation due to coalition between H-MGs is an important issue...

  4. Influências dos modos de operação nas emissões de poluentes provenientes de veículos flex em região urbana

    Directory of Open Access Journals (Sweden)

    Julie Anne Holanda Azevedo

    2017-08-01

    Full Text Available This work proposes to verify the influence of operating modes on pollutants emissions of flex - fuel vehicles. For this, a real driving cycle was developed for the flex light vehicle in an urban street of the Fortaleza city. For data collection was used a method of instant collection of kinematic parameters from engine, road and vehicle emissions. Due to the local characteristics of the traffic, a greater representatively of the idle operating modes was observed. In general, there was a greater influence of the acceleration mode on pollutant emissions and fuel consumption. The highest average CO2 emission rate was observed during acceleration mode (6.38 mg/s, followed by the idle mode (4.70 mg/s. For the CO pollutant, the highest average emission rate was also observed during the acceleration mode (55.60 μg/s, followed by the idle mode (35.01 μg/s. For the NOx pollutant, higher emission rates were observed in the acceleration mode, 5.08 μg/km and 1.98 μg/km for the idle mode. The average fuel consumption in the acceleration mode was 6.61 L/100 km during the tests, followed by idle and deceleration modes, with 4.84 and 3.39 L/100 km, respectively.

  5. Benjamin Banneker and the Law of Sines

    Science.gov (United States)

    Mahoney, John F.

    2005-01-01

    Benjamin Banneker, a self-taught mathematician, surveyor and astronomer published annual almanacs containing his astronomical observations and predictions. Banneker who also used logarithms to apply the Law of Sines believed that the method used to solve a mathematical problem depends on the tools available.

  6. Meteoric Impact and Ion Density Calculation in the Nighttime ...

    Indian Academy of Sciences (India)

    Bhavin

    2013-11-08

    Nov 8, 2013 ... Pandya, B. M., and S. A. Haider (2012), Meteor impact perturbation in the lower ionosphere of Mars: MGS observations,. Planet. Space Sci., 63, 105-109, doi: 10.1016/j.pss.2011.09.013. Page 6. Pandya, B. M., and S. A. Haider (2012), Meteor impact perturbation in the lower ionosphere of Mars: MGS ...

  7. Mars Orbiter Camera Views the 'Face on Mars' - Comparison with Viking

    Science.gov (United States)

    1998-01-01

    Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.In this comparison, the best Viking image has been enlarged to 3.3 times its original resolution, and the MOC image has been decreased by a similar 3.3 times, creating images of roughly the same size. In addition, the MOC images have been geometrically transformed to a more overhead projection (different from the mercator map projection of PIA01440 & 1441) for ease of comparison with the Viking image. The left image is a portion of Viking Orbiter 1 frame 070A13, the middle image is a portion of MOC frame shown normally, and the right image is the same MOC frame but with the brightness inverted to simulate the approximate lighting conditions of the Viking image.Processing Image processing has been applied to the images in order to improve the visibility of features. This processing included the following steps: The image was

  8. Fresh Impact Crater and Rays in Tharsis

    Science.gov (United States)

    2002-01-01

    The Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) Extended Mission has included dozens of opportunities to point the spacecraft directly at features of interest so that pictures of things not seen during the earlier Mapping Mission can be obtained. The example shown here is a small meteorite impact crater in northern Tharsis near 17.2oN, 113.8oW. Viking Orbiter images from the late 1970's showed at this location what appeared to be a dark patch with dark rays emanating from a brighter center. The MOC team surmised that the dark rays may be indicating the location of afresh crater formed by impact sometime in the past few centuries (since dark ray are quickly covered by dust falling out of the martian atmosphere). All through MOC's Mapping Mission in 1999 and 2000, attempts were made to image the crater as predictions indicated that the spacecraft would pass over the site, but the crater was never seen. Finally, in June 2001, Extended Mission operations allowed the MOC team to point the spacecraft (and hence the camera, which is fixed to the spacecraft)directly at the center of the dark rays, where we expected to find the crater.The picture on the left (above, A) is a mosaic of three MOC high resolution images and one much lower-resolution Viking image. From left to right, the images used in the mosaic are: Viking 1 516A55, MOC E05-01904, MOCM21-00272, and MOC M08-03697. Image E05-01904 is the one taken in June 2001 by pointing the spacecraft. It captured the impact crater responsible for the rays. A close-up of the crater, which is only 130 meters (427 ft)across, is shown on the right (above, B). This crater is only one-tenth the size of the famous Meteor Crater in northern Arizona.The June 2001 MOC image reveals many surprises about this feature. For one, the crater is not located at the center of the bright area from which the dark rays radiate. The rays point to the center of this bright area, not the crater. Further, the dark material ejected from the

  9. Sequential Isolation of Saturated, Aromatic, Resinic and Asphaltic Fractions Degrading Bacteria from Oil Contaminated Soil in South Sumatera

    Directory of Open Access Journals (Sweden)

    Pingkan Aditiawati

    2012-04-01

    Full Text Available Sequential isolation has been conducted to obtain isolates of saturated, aromatic, resin, and asphaltene fractions degrading bacteria from oil contaminated sites. Five soil samples were collected from South Sumatera. These were analyzed using soil extract medium enriched with oil recovery or Remaining-Oil recovery Degradated (ROD as sole carbon and energy sources according to the isolation stage. ROD at the end of every isolation stage analyzed oil fractions by use of the SARA analysis method. Six isolates of bacteria have been selected, one isolate was fraction saturates degrading bacteria that are Mycobacterium sp. T1H2D4-7 at degradation rate 0.0199 mgs/h with density 8.4x106 cfu/g from stage I. The isolate T2H1D2-4, identified as Pseudomonas sp. was fraction aromatics degrading bacteria at accelerate 0.0141 mgs/h with density 5.1x106 cfu/g are obtained at stage II. Two isolates namely Micrococcus sp. T3H2D4-2 and Pseudomonas sp. T1H1D5-5 were fraction resins degrading bacteria by accelerate 0.0088 mgs/h at density 5.6x106 cfu/g and 0.0089 mgs/h at density 5.7x106 cfu/g are obtained at stage III. Isolation of stage IV has been obtained two isolates Pseudomonas sp. T4H1D3-1and Pseudomonas sp. T4H3D5-4 were fraction asphaltenes degrading bacteria by accelerate 0.0057 mgs/h at density 5.6x106 cfu/g and accelerate 0.0058 mgs/h at density 5.7x106 cfu/g.

  10. Effects of clove oil-phospholipid mixtures on rheology of gum tragacanth - possible application for surfactant action on mucus gel simulants.

    Science.gov (United States)

    Banerjee, R; Puniyani, R R

    2000-01-01

    The present study evaluates the effectiveness of specialised biomaterials consisting of clove oil- phospholipid mixtures as possible substitute surfactants in diseases of altered mucus viscosity by studying their effect on the viscosity of mucus gel simulants in vitro. Test surfactants consisting of phospholipid-clove oil mixtures in the ratio of 1 part of oil to 9 parts of phospholipid were prepared. The phospholipids used were dipalmitoyl phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) and binary mixtures of PC: PE and PC: PG in the ratio of 2 parts of PC to 3 parts of PE or PG. The effects of the phospholipid-clove oil mixtures on the viscosity of mucus gel simulant (MGS: a polymeric gel consisting predominantly of gum tragacanth and simulating respiratory mucus), was studied by application of steady shear rates ranging from 0.512 to 51.2/s in a concentric cylinder viscometer at 37 degrees C. The change in MGS viscosity, after incubation with surfactants, was found to have a non-Newtonian character and to follow the power law model with R2 values >0.8. The addition of clove oil-phospholipid mixtures caused a decrease in the MGS viscosity when compared with the effect of the phospholipid alone at low shear rates in case of PC, PG and PCPG. The combination of PC : PG with clove oil caused ratios of change in MGS viscosity < 1 i.e., caused a decrease in the MGS viscosity. PC: PG with clove oil was capable of lowering MGS viscosity and should be further researched as possible therapies for diseases of altered mucus rheology.

  11. Human performance in radiological survey scanning

    International Nuclear Information System (INIS)

    Brown, W.S.; Abelquist, E.W.

    1998-03-01

    The probability of detecting residual contamination in the field using portable radiological survey instruments depends not only on the sensitivity of the instrumentation used in scanning, but also on the surveyor's performance. This report provides a basis for taking human performance into account in determining the minimum level of activity detectable by scanning. A theoretical framework was developed (based on signal detection theory) which allows influences on surveyors to be anticipated and understood, and supports a quantitative assessment of performance. The performance of surveyors under controlled yet realistic field conditions was examined to gain insight into the task and to develop means of quantifying performance. Then, their performance was assessed under laboratory conditions to quantify more precisely their ability to make the required discriminations. The information was used to characterize surveyors' performance in the scanning task and to provide a basis for predicting levels of radioactivity that are likely to be detectable under various conditions by surveyors using portable survey instruments

  12. The Needs for Professionalism and Competency in the Construction Industry

    Directory of Open Access Journals (Sweden)

    Adebiyi John Oladotun

    2016-09-01

    Full Text Available The quantity surveyors, in the present day construction industry, analyze cost components of a construction project in a scientific way and applies the results of the analysis to a variety of financial and economic problems confronting the developer and the designer. However, competence, in any sphere of work, can be a difficult concept to pin down, especially, when it relates to professional occupations where such roles are complex and involved diverse professionals in the built environment sector. This paper aims to investigate the competencies of quantity surveyors in the discharge of its professional duties by evaluating the effects of professional competency on quantity surveying practices in Nigeria. The study population comprised professional quantity surveyors who are in the private construction/consulting firms in Lagos State, Nigeria. Data were obtained to investigate the professional views on the quantity surveying profession, the roles of quantity surveyors in the construction industry and the need for professionalism and competencies in the surveying industry. Questionnaires were administered to randomly select 200 practicing quantity surveyors in Lagos state. Findings revealed that the major role of quantity surveyors in the construction industry is the preparation of the bill of quantity as it ranked 1st with RII value of 1.00; it was also discovered that quantity surveyors were in agreement with client service delivery as the first ethical standard that construction professionals should consider when performing their professional obligations in order to avoid project failure and over-cost. It is therefore recommended that the professional bodies and the academia should organize proper and adequate service trainings, workshops and seminars which will enhance the possibility of acquiring more skills and experience so as to improve competence in the discharge of quantity surveyors professional duties.

  13. The Need for Professionalism and Competencies in the Construction Industry

    Directory of Open Access Journals (Sweden)

    Adebiyi John Oladotun

    2017-01-01

    Full Text Available The quantity surveyors, in the present day construction industry, analyze cost components of a construction project in a scientific way and applies the results of the analysis to a variety of financial and economic problems confronting the developer and the designer. However, competence, in any sphere of work, can be a difficult concept to pin down, especially, when it relates to professional occupations where such roles are complex and involved diverse professionals in the built environment sector. This paper aims to investigate the competencies of quantity surveyors in the discharge of its professional duties by evaluating the effects of professional competency on quantity surveying practices in Nigeria. The study population comprised professional quantity surveyors who are in the private construction/consulting firms in Lagos State, Nigeria. Data were obtained to investigate the professional views on the quantity surveying profession, the roles of quantity surveyors in the construction industry and the need for professionalism and competencies in the surveying industry. Questionnaires were administered to randomly select 200 practicing quantity surveyors in Lagos state. Findings revealed that the major role of quantity surveyors in the construction industry is the preparation of the bill of quantity as it ranked 1st with RII value of 1.00; it was also discovered that quantity surveyors were in agreement with client service delivery as the first ethical standard that construction professionals should consider when performing their professional obligations in order to avoid project failure and over-cost. It is therefore recommended that the professional bodies and the academia should organize proper and adequate service trainings, workshops and seminars which will enhance the possibility of acquiring more skills and experience so as to improve competence in the discharge of quantity surveyors professional duties.

  14. A Three-Stage Optimal Approach for Power System Economic Dispatch Considering Microgrids

    Directory of Open Access Journals (Sweden)

    Wei-Tzer Huang

    2016-11-01

    Full Text Available The inclusion of microgrids (MGs in power systems, especially distribution-substation-level MGs, significantly affects power systems because of the large volumes of import and export power flows. Consequently, power dispatch has become complicated, and finding an optimal solution is difficult. In this study, a three-stage optimal power dispatch model is proposed to solve such dispatch problems. In the proposed model, the entire power system is divided into two parts, namely, the main power grid and MGs. The optimal power dispatch problem is resolved on the basis of multi-area concepts. In stage I, the main power system economic dispatch (ED problem is solved by sensitive factors. In stage II, the optimal power dispatches of the local MGs are addressed via an improved direct search method. In stage III, the incremental linear models for the entire power system can be established on the basis of the solutions of the previous two stages and can be subjected to linear programming to determine the optimal reschedules from the original dispatch solutions. The proposed method is coded using Matlab and tested by utilizing an IEEE 14-bus test system to verify its feasibility and accuracy. Results demonstrated that the proposed approach can be used for the ED of power systems with MGs as virtual power plants.

  15. Comparative transcriptome analysis on the synthesis pathway of honey bee (Apis mellifera) mandibular gland secretions.

    Science.gov (United States)

    Wu, YuQi; Zheng, HuoQing; Corona, Miguel; Pirk, Christian; Meng, Fei; Zheng, YuFei; Hu, FuLiang

    2017-07-03

    Secretions from mandibular glands (MGs) have important caste-specific functions that are associated with the social evolution of honey bees. To gain insights into the molecular architecture underlying these caste differences, we compared the gene expression patterns of MGs from queens, queenright workers (WQRs) and queenless workers (WQLs) using high-throughput RNA-sequencing technology. In total, we identified 46 candidate genes associated with caste-specific biosynthesis of fatty acid pheromones in the MG, including members of cytochrome P450 (CYP450) family and genes involved in fatty acid β-oxidation and ω-oxidation. For further identification of the CYP450s genes involved in the biosynthesis of MG secretions, we analyzed by means of qPCR, the expression levels of six of the CYP450 genes most abundantly expressed in the transcriptome analysis across different castes, ages, tasks and tissues. Our analysis revealed that CYP6AS8 and CYP6AS11, the most abundantly expressed CYP450 genes in worker and queen MGs, respectively, are selectively expressed in the MGs of workers and queens compared to other tissues. These results suggest that these genes might be responsible for the critical bifurcated hydroxylation process in the biosynthesis pathway. Our study contributes to the description of the molecular basis for the biosynthesis of fatty acid-derived pheromones in the MGs.

  16. Starting and developing a surveying business

    CERN Document Server

    Imber, Austen

    2013-01-01

    Starting and Developing a Surveying Business shows how surveyors can develop their own successful small business. For surveyors thinking of taking this step, guidance is provided on the pros and cons which will help the right decision to be made, and the key factors which help see the business through its early stages. For surveyors already running their own small business, consideration is given to factors which will help profitability and growth potential.

  17. Mass gatherings: A one-stop opportunity to complement global disease surveillance

    Directory of Open Access Journals (Sweden)

    Habida Elachola

    2016-01-01

    Full Text Available Emerging infections including those resulting from the bioterrorist use of infectious agents have indicated the need for global health surveillance. This paper reviews multiple surveillance opportunities presented by mass gatherings (MGs that align with fundamental questions in epidemiology (why, what, who, where, when and how. Some MGs bring together large, diverse population groups coming from countries with high prevalence of communicable diseases and disparate surveillance capacities. MGs have the potential to exacerbate the transmission dynamics of infectious diseases due to various factors including the high population density and rigor of events, increase in number of people with underlying diseases that predisposes them to disease acquisition, mixing of people from countries or regions with and without efficient disease control efforts, and varying endemicity or existence of communicable diseases in home countries. MGs also have the potential to increase the opportunities for mechanical and even heat-related injuries, morbidity or deaths from accidents, alcohol use, deliberate terrorist attacks with biological agents and/or with explosives and from exacerbation of pre-existing conditions. Responding to these wider range of events may require the use of novel bio-surveillance systems designed to collect data from different sources including electronic and non-electronic medical records from emergency departments and hospitalisations, laboratories, medical examiners, emergency call centres, veterinary, food processors, drinking water systems and even other non-traditional sources such as over-the-counter drug sales and crowd photographs. Well-structured, interoperable real-time surveillance and reporting systems should be integral to MG planning. The increase in magnitude of participants exceeding millions and diversity of people attending MGs can be proactively used to conduct active surveillance of communicable and non

  18. Meier-Gorlin syndrome.

    Science.gov (United States)

    de Munnik, Sonja A; Hoefsloot, Elisabeth H; Roukema, Jolt; Schoots, Jeroen; Knoers, Nine V A M; Brunner, Han G; Jackson, Andrew P; Bongers, Ernie M H F

    2015-09-17

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females and urogenital anomalies, such as cryptorchidism and hypoplastic labia minora and majora. Typical facial characteristics during childhood comprise a small mouth with full lips and micro-retrognathia. During ageing, a narrow, convex nose becomes more prominent. The diagnosis MGS should be considered in patients with at least two of the three features of the clinical triad of microtia, patellar anomalies, and pre- and postnatal growth retardation. In patients with short stature and/or microtia, the patellae should be assessed with care by ultrasonography before age 6 or radiography thereafter. Mutations in one of five genes (ORC1, ORC4, ORC6, CDT1, and CDC6) of the pre-replication complex, involved in DNA-replication, are detected in approximately 67-78% of patients with MGS. Patients with ORC1 and ORC4 mutations appear to have the most severe short stature and microcephaly. Management should be directed towards in-depth investigation, treatment and prevention of associated problems, such as growth retardation, feeding problems, hearing loss, luxating patellae, knee pain, gonarthrosis, and possible pulmonary complications due to congenital pulmonary emphysema with or without broncho- or laryngomalacia. Growth hormone treatment is ineffective in most patients with MGS, but may be effective in patients in whom growth continues to decrease after the first year of life (usually growth velocity normalizes after the first year) and with low levels of IGF1. At present, few data is available about reproduction of females with MGS, but the risk of premature labor might be increased. Here, we propose experience-based guidelines for the regular care and treatment of MGS patients.

  19. Origin of Shear Stability and Compressive Ductility Enhancement of Metallic Glasses by Metal Coating

    Science.gov (United States)

    Sun, B. A.; Chen, S. H.; Lu, Y. M.; Zhu, Z. G.; Zhao, Y. L.; Yang, Y.; Chan, K. C.; Liu, C. T.

    2016-01-01

    Metallic glasses (MGs) are notorious for the poor macroscopic ductility and to overcome the weakness various intrinsic and extrinsic strategies have been proposed in past decades. Among them, the metal coating is regarded as a flexible and facile approach, yet the physical origin is poorly understood due to the complex nature of shear banding process. Here, we studied the origin of ductile enhancement in the Cu-coating both experimentally and theoretically. By examining serrated shear events and their stability of MGs, we revealed that the thin coating layer plays a key role in stopping the final catastrophic failure of MGs by slowing down shear band dynamics and thus retarding its attainment to a critical instable state. The mechanical analysis on interplay between the coating layer and shear banding process showed the enhanced shear stability mainly comes from the lateral tension of coating layer induced by the surface shear step and the bonding between the coating layer and MGs rather than the layer thickness is found to play a key role in contributing to the shear stability. PMID:27271435

  20. A Novel Decentralized Economic Operation in Islanded AC Microgrids

    Directory of Open Access Journals (Sweden)

    Hua Han

    2017-06-01

    Full Text Available Droop schemes are usually applied to the control of distributed generators (DGs in microgrids (MGs to realize proportional power sharing. The objective might, however, not suit MGs well for economic reasons. Addressing that issue, this paper proposes an alternative droop scheme for reducing the total active generation costs (TAGC. Optimal economic operation, DGs’ capacity limitations and system stability are fully considered basing on DGs’ generation costs. The proposed scheme utilizes the frequency as a carrier to realize the decentralized economic operation of MGs without communication links. Moreover, a fitting method is applied to balance DGs’ synchronous operation and economy. The effectiveness and performance of the proposed scheme are verified through simulations and experiments.

  1. Comparison of forced expiratory spirometric flow changes following ...

    African Journals Online (AJOL)

    Group B received intrathecal anaesthesia 15 mgs of bupivacaine with 0.5 ml of normal saline and Group BF received 15 mgs of bupivacaine with 0.5 ml of fentanyl (25 μg) intrathecally. The patients were instructed about the performance of the spirometry on the previous evening of the surgery. Forced vital capacity, forced ...

  2. Clustering, microalloying and mechanical properties in Cu/Zr-based glassy models by molecular dynamics simulations and ab-initio computations

    Energy Technology Data Exchange (ETDEWEB)

    Lekka, Ch.E.; Bokas, G.B. [University of Ioannina, Department of Materials Science and Engineering, Ioannina 45100 (Greece); Almyras, G.A. [University of Ioannina, Department of Physics, Ioannina 45110 (Greece); Papageorgiou, D.G. [University of Ioannina, Department of Materials Science and Engineering, Ioannina 45100 (Greece); Evangelakis, G.A., E-mail: gevagel@cc.uoi.gr [University of Ioannina, Department of Physics, Ioannina 45110 (Greece)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Cu-Zr MGs consist of interpenetrating ICO-like clusters (superclusters (SCs)). Black-Right-Pointing-Pointer The SCs participate in the accommodation of the tensile deformation. Black-Right-Pointing-Pointer The SCs may exhibit a free of bonds (FoB) plane. Black-Right-Pointing-Pointer Al microalloying changes the SCs' electronic structure inducing FoB planes. Black-Right-Pointing-Pointer Control of SCs' electronic structure may lead to control of MGs' properties. - Abstract: We present results on the microstructure of Cu-Zr metallic glasses (MGs) at equilibrium and under tensile deformation by means of large scale molecular dynamics (MD) simulations and density functional theory (DFT) calculations. We found that the MGs are composed by interpenetrating icosahedral-like (ICO) clusters forming superclusters (SCs). The deformation accommodation is associated with the destruction and recreation of these ICO clusters and SCs. DFT calculations on the Cu{sub 13}Zr{sub 10} SCs with Cu-Cu core atoms revealed the presence of a free of bonds (FoB) plane that could be viewed as analog of a slip plane of the crystalline materials. The microalloying (MA) effect in a similar SC (one of the core atoms substituted by Al) yielded that Al is associated with the formation of a FoB plane. These results provide possible explanations of the experimental findings referring to the short range order, the MA effect and could potentially be used for the design of new MGs.

  3. Meckel Gruber syndrome, A case report

    Science.gov (United States)

    Aslan, Kiper; Külahçı Aslan, Elif; Orhan, Adnan; Atalay, Mehmet Aral

    2015-01-01

    ABSTRACT. Introduction: Meckel-Gruber Syndrome was first described by J R Meckel in 1822. It is an autosomal recessive disorder, and is caused by the failure of mesodermal induction. The typical triad of Meckel-Gruber Syndrome (MGS) involves meningo-encephalocele, polycystic kidneys and postaxial polydactyly. The worldwide incidence varies from 1 in 1.300 to 1 in 140.000 live births. Case: In this report, we present a case of MGS in which the diagnosis was made at 19 weeks of gestation based on ultrasonographic findings of the typical triad of the disease (encephalocele, polycystic kidneys, and polydactyly) These features were suggestive of the diagnosis of Meckel Gruber Syndrome (MGS). She had also placenta previa totalis. The patient was counselled regarding the lethal outcome of MGS. Unfortunately, the family did not approve the termination of pregnancy. At the 32nd week, she referred to hospital with complaints of vaginal bleeding and uterine contractions. An emergency cesarean section was perfomed due to plasental malposition. A 1380 gr, female fetus was delivered. First and 5th minute Apgar scores were 1 and 0, respectively. Consequently, the baby died after 45 minutes of neonatal resuscitation. Conclusıon: MGS is a lethal disorder. One cannot speak about survival of the fetus because of the pulmonary hypoplasia. The parents should be counseled about prognosis of the fetus and the outcome. Counselers should strictly give information about the recurrence risk for the next pregnancies. PMID:26037304

  4. Correlation between relaxations and plastic deformation, and elastic model of flow in metallic glasses and glass-forming liquids

    International Nuclear Information System (INIS)

    Wang Weihua

    2011-01-01

    We study the similarity and correlations between relaxations and plastic deformation in metallic glasses (MGs) and MG-forming liquids. It is shown that the microscope plastic events, the initiation and formation of shear bands, and the mechanical yield in MGs where the atomic sites are topologically unstable induced by applied stress, can be treated as the glass to supercooled liquid state transition induced by external shear stress. On the other hand, the glass transition, the primary and secondary relaxations, plastic deformation and yield can be attributed to the free volume increase induced flow, and the flow can be modeled as the activated hopping between the inherent states in the potential energy landscape. We then propose an extended elastic model to describe the flow based on the energy landscape theory. That is, the flow activation energy density is linear proportional to the instantaneous elastic moduli, and the activation energy density ρ E is determined to be a simple expression of ρ E =(10/11)G+(1/11)K. The model indicates that both shear and bulk moduli are critical parameters accounting for both the homogeneous and inhomogeneous flows in MGs and MG-forming liquids. The elastic model is experimentally certified. We show that the elastic perspectives offers a simple scenario for the flow in MGs and MG-forming liquids and are suggestive for understanding the glass transition, plastic deformation, and nature and characteristics of MGs

  5. An optimal autonomous microgrid cluster based on distributed generation droop parameter optimization and renewable energy sources using an improved grey wolf optimizer

    Science.gov (United States)

    Moazami Goodarzi, Hamed; Kazemi, Mohammad Hosein

    2018-05-01

    Microgrid (MG) clustering is regarded as an important driver in improving the robustness of MGs. However, little research has been conducted on providing appropriate MG clustering. This article addresses this shortfall. It proposes a novel multi-objective optimization approach for finding optimal clustering of autonomous MGs by focusing on variables such as distributed generation (DG) droop parameters, the location and capacity of DG units, renewable energy sources, capacitors and powerline transmission. Power losses are minimized and voltage stability is improved while virtual cut-set lines with minimum power transmission for clustering MGs are obtained. A novel chaotic grey wolf optimizer (CGWO) algorithm is applied to solve the proposed multi-objective problem. The performance of the approach is evaluated by utilizing a 69-bus MG in several scenarios.

  6. Progressive Transformation between Two Magnetic Ground States for One Crystal Structure of a Chiral Molecular Magnet.

    Science.gov (United States)

    Li, Li; Nishihara, Sadafumi; Inoue, Katsuya; Kurmoo, Mohamedally

    2016-03-21

    We report the exceptional observation of two different magnetic ground states (MGS), spin glass (SG, T(B) = 7 K) and ferrimagnet (FI, T(C) = 18 K), for one crystal structure of [{Mn(II)(D/L-NH2ala)}3{Mn(III)(CN)6}]·3H2O obtained from [Mn(CN)6](3-) and D/L-aminoalanine, in contrast to one MGS for [{Mn(II)(L-NH2ala)}3{Cr(III)(CN)6}]·3H2O. They consist of three Mn(NH2ala) helical chains bridged by M(III)(CN)6 to give the framework with disordered water molecules in channels and between the M(III)(CN)6. Both MGS are characterized by a negative Weiss constant, bifurcation in ZFC-FC magnetizations, blocking of the moments, both components of the ac susceptibilities, and hysteresis. They differ in the critical temperatures, absolute magnetization for 5 Oe FC (lack of spontaneous magnetization for the SG), and the shapes of the hysteresis and coercive fields. While isotropic pressure increases both T(crit) and the magnetizations linearly and reversibly in each case, dehydration progressively transforms the FI into the SG as followed by concerted in situ magnetic measurements and single-crystal diffraction. The relative strengths of the two moderate Mn(III)-CN-Mn(II) antiferromagnetic (J1 and J2), the weak Mn(II)-OCO-Mn(II) (J3), and Dzyaloshinkii-Moriya antisymmetric (DM) interactions generate the two sets of characters. Examination of the bond lengths and angles for several crystals and their corresponding magnetic properties reveals a correlation between the distortion of Mn(III)(CN)6 and the MGS. SG is favored by higher magnetic anisotropy by less distorted Mn(III)(CN)6 in good accordance with the Mn-Cr system. This conclusion is also born out of the magnetization measurements on orientated single crystals with fields parallel and perpendicular to the unique c axis of the hexagonal space group.

  7. Gas adsorption in Mg-porphyrin-based porous organic frameworks: A computational simulation by first-principles derived force field.

    Science.gov (United States)

    Pang, Yujia; Li, Wenliang; Zhang, Jingping

    2017-09-15

    A novel type of porous organic frameworks, based on Mg-porphyrin, with diamond-like topology, named POF-Mgs is computationally designed, and the gas uptakes of CO 2 , H 2 , N 2 , and H 2 O in POF-Mgs are investigated by Grand canonical Monte Carlo simulations based on first-principles derived force fields (FF). The FF, which describes the interactions between POF-Mgs and gases, are fitted by dispersion corrected double-hybrid density functional theory, B2PLYP-D3. The good agreement between the obtained FF and the first-principle energies data confirms the reliability of the FF. Furthermore our simulation shows the presence of a small amount of H 2 O (≤ 0.01 kPa) does not much affect the adsorption quantity of CO 2 , but the presence of higher partial pressure of H 2 O (≥ 0.1 kPa) results in the CO 2 adsorption decrease significantly. The good performance of POF-Mgs in the simulation inspires us to design novel porous materials experimentally for gas adsorption and purification. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Feasibility Studies for Production of Pellet Grade Concentrate from Sub Grade Iron Ore Using Multi Gravity Separator

    Science.gov (United States)

    Rao, Gottumukkala Venkateswara; Markandeya, R.; Kumar, Rajan

    2018-04-01

    An attempt has been made to utilise Sub Grade Iron Ore by producing pellet grade concentrate from Deposit 5, Bacheli Complex, Bailadila, Chhattisgarh, India. The `as received' Run of Mine (ROM) sample assayed 40.80% Fe, 40.90% SiO2. Mineralogical studies indicated that the main ore mineral is Hematite and lone gangue mineral is Quartz. Mineral liberation studies indicated that, the ore mineral Hematite and gangue mineral Quartz are getting liberated below 100 microns. The stage crushed and ground sample was subjected to concentration by using a Multi Gravity Separator (MGS). Rougher Multi Gravity Separation (MGS) experimental results were optimised to recover highest possible iron values. A concentrate of 55.80% Fe with a yield of 61.73% by weight with a recovery of 84.42% Iron values was obtained in rougher MGS concentrate. Further experiments were carried out with rougher MGS concentrate to produce a concentrate suitable for commercial grade pellet concentrate. It was proved that a concentrate assaying 66.67% Fe, 3.12% SiO2 with an yield of 45.08% by weight and with a recovery of 73.67% iron values in the concentrate.

  9. Shotgun proteomics deciphered age/division of labor-related functional specification of three honeybee (Apis mellifera L.) exocrine glands.

    Science.gov (United States)

    Fujita, Toshiyuki; Kozuka-Hata, Hiroko; Hori, Yutaro; Takeuchi, Jun; Kubo, Takeo; Oyama, Masaaki

    2018-01-01

    The honeybee (Apis mellifera L.) uses various chemical signals produced by the worker exocrine glands to maintain the functioning of its colony. The roles of worker postcerebral glands (PcGs), thoracic glands (TGs), and mandibular glands (MGs) and the functional changes they undergo according to the division of labor from nursing to foraging are not as well studied. To comprehensively characterize the molecular roles of these glands in workers and their changes according to the division of labor of workers, we analyzed the proteomes of PcGs, TGs, and MGs from nurse bees and foragers using shotgun proteomics technology. We identified approximately 2000 proteins from each of the nurse bee or forager glands and highlighted the features of these glands at the molecular level by semiquantitative enrichment analyses of frequently detected, gland-selective, and labor-selective proteins. First, we found the high potential to produce lipids in PcGs and MGs, suggesting their relation to pheromone production. Second, we also found the proton pumps abundant in TGs and propose some transporters possibly related to the saliva production. Finally, our data unveiled candidate enzymes involved in labor-dependent acid production in MGs.

  10. Traveling Weather Disturbances in Mars Southern Extratropics: Sway of the Great Impact Basins

    Science.gov (United States)

    Hollingsworth, Jeffery L.

    2016-01-01

    As on Earth, between late autumn and early spring on Mars middle and high latitudes within its atmosphere support strong mean thermal contrasts between the equator and poles (i.e. "baroclinicity"). Data collected during the Viking era and observations from both the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) indicate that this strong baroclinicity supports vigorous, large-scale eastward traveling weather systems (i.e. transient synoptic-period waves). Within a rapidly rotating, differentially heated, shallow atmosphere such as on Earth and Mars, such large-scale, extratropical weather disturbances are critical components of the global circulation. These wave-like disturbances act as agents in the transport of heat and momentum, and moreover generalized tracer quantities (e.g., atmospheric dust, water vapor and water-ice clouds) between low and high latitudes of the planet. The character of large-scale, traveling extratropical synoptic-period disturbances in Mars' southern hemisphere during late winter through early spring is investigated using a high-resolution Mars global climate model (Mars GCM). This global circulation model imposes interactively lifted (and radiatively active) dust based on a threshold value of the instantaneous surface stress. Compared to observations, the model exhibits a reasonable "dust cycle" (i.e. globally averaged, a more dusty atmosphere during southern spring and summer occurs). In contrast to their northern-hemisphere counterparts, southern synoptic-period weather disturbances and accompanying frontal waves have smaller meridional and zonal scales, and are far less intense synoptically. Influences of the zonally asymmetric (i.e. east-west varying) topography on southern large-scale weather disturbances are examined. Simulations that adapt Mars' full topography compared to simulations that utilize synthetic topographies emulating essential large-scale features of the southern middle latitudes indicate that Mars

  11. Dayside ionosphere of Mars: Empirical model based on data from the MARSIS instrument

    Czech Academy of Sciences Publication Activity Database

    Němec, F.; Morgan, D. D.; Gurnett, D. A.; Duru, F.; Truhlík, Vladimír

    2011-01-01

    Roč. 116, - (2011), E07003/1-E07003/14 ISSN 0148-0227 Institutional research plan: CEZ:AV0Z30420517 Keywords : RADIO OCCULTATION MEASUREMENTS * GLOBAL SURVEYOR OBSERVATIONS * MARTIAN IONOSPHERE Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.021, year: 2011 http://www.agu.org/pubs/crossref/2011/2010JE003789.shtml

  12. Maturity group classification and maturity locus genotyping of early-maturing soybean varieties from high-latitude cold regions.

    Science.gov (United States)

    Jia, Hongchang; Jiang, Bingjun; Wu, Cunxiang; Lu, Wencheng; Hou, Wensheng; Sun, Shi; Yan, Hongrui; Han, Tianfu

    2014-01-01

    With the migration of human beings, advances of agricultural sciences, evolution of planting patterns and global warming, soybeans have expanded to both tropical and high-latitude cold regions (HCRs). Unlike other regions, HCRs have much more significant and diverse photoperiods and temperature conditions over seasons or across latitudes, and HCR soybeans released there show rich diversity in maturity traits. However, HCR soybeans have not been as well classified into maturity groups (MGs) as other places. Therefore, it is necessary to identify MGs in HCRs and to genotype the maturity loci. Local varieties were collected from the northern part of Northeast China and the far-eastern region of Russia. Maturity group reference (MGR) soybeans of MGs MG000, MG00, and MG0 were used as references during field experiments. Both local varieties and MGR soybeans were planted for two years (2010-2011) in Heihe (N 50°15', E 127°27', H 168.5 m), China. The days to VE (emergence), R1 (beginning bloom) and R7 (beginning maturity) were recorded and statistically analyzed. Furthermore, some varieties were further genotyped at four molecularly-identified maturity loci E1, E2, E3 and E4. The HCR varieties were classified into MG0 or even more early-maturing. In Heihe, some varieties matured much earlier than MG000, which is the most early-maturing known MG, and clustered into a separate group. We designated the group as MG0000, following the convention of MGs. HCR soybeans had relatively stable days to beginning bloom from emergence. The HCR varieties diversified into genotypes of E1, E2, E3 and E4. These loci had different effects on maturity. HCRs diversify early-maturing MGs of soybean. MG0000, a new MG that matures much earlier than known MGs, was developed. HCR soybean breeding should focus more on shortening post-flowering reproductive growth. E1, E2, E3, and E4 function differentially.

  13. Supervisory Control for Real Time Reactive Power Flow Optimization in Islanded Microgrids

    DEFF Research Database (Denmark)

    Milczarek, Adam; Vasquez, Juan Carlos; Malinowski, Mariusz

    2013-01-01

    -line measurements. Similarly to any process system, MG hierarchical control is divided into three levels. However, an additional control algorithm is required to manage power transmission between sources and loads, maximizing efficiency and minimizing transmission losses. This real-time optimization problem......A microgrid (MG) is a local energy system consisting of a number of energy sources, energy storage units and loads that operate connected to the main electrical grid or autonomously. MGs include wind, solar or other renewable energy sources. MGs provide flexibility, reduce the main electricity grid...... dependence and contribute to change the large centralized production paradigm to local and distributed generation. However, such energy systems require complex management, advanced control and optimization. Interest on MGs hierarchical control has increased due to the availability of cheap on...

  14. ISSN 2073 ISSN 2073 9990 East Cent. Afr. J. s 9990 East Cent. Afr ...

    African Journals Online (AJOL)

    Hp 630 Dual Core

    birth weight likewise the findings obtained by Homa et al6 signifying low birth weight to not be a direct risk for developing small bowel obstruction in newborns. But this observation was statistically insignificant in this study. Most of the neonates were delivered at term similar to the results obtained by another surveyor6 this ...

  15. Surface Properties of Squalene/Meibum Films and NMR Confirmation of Squalene in Tears

    Directory of Open Access Journals (Sweden)

    Slavyana Ivanova

    2015-09-01

    Full Text Available Squalene (SQ possesses a wide range of pharmacological activities (antioxidant, drug carrier, detoxifier, hydrating, emollient that can be of benefit to the ocular surface. It can come in contact with human meibum (hMGS; the most abundant component of the tear film lipid layer as an endogenous tear lipid or from exogenous sources as eyelid sebum or pharmaceuticals. The aims of this study were to determine (i if SQ is in tear lipids and (ii its influence on the surface properties of hMGS films. Heteronuclear single quantum correlation NMR confirmed 7 mol % SQ in Schirmer’s strips extracts. The properties of SQ/hMGS pseudo-binary films at the air/water interface were studied with Langmuir surface balance, stress-relaxation dilatational rheology and Brewster angle microscopy. SQ does not possess surfactant properties. When mixed with hMGS squalene (i localized over the layers’ thinner regions and (ii did not affect the film pressure at high compression. Therefore, tear SQ is unlikely to instigate dry eye, and SQ can be used as a safe and “inert” ingredient in formulations to protect against dry eye. The layering of SQ over the thinner film regions in addition to its pharmacological properties could contribute to the protection of the ocular surface.

  16. The pathogenic persona of community-associated oral streptococci.

    Science.gov (United States)

    Whitmore, Sarah E; Lamont, Richard J

    2011-07-01

    The mitis group streptococci (MGS) are widespread in the oral cavity and are traditionally associated with oral health. However, these organisms have many attributes that contribute to the development of pathogenic oral communities. MGS adhere rapidly to saliva-coated tooth surfaces, thereby providing an attachment substratum for more overtly pathogenic organisms such as Porphyromonas gingivalis, and the two species assemble into heterotypic communities. Close physical association facilitates physiologic support, and pathogens such as Aggregatibacter actinomycetemcomitans display resource partitioning to favour carbon sources generated by streptococcal metabolism. MGS exchange information with community members through a number of interspecies signalling systems including AI-2 and contact dependent mechanisms. Signal transduction systems induced in P. gingivalis are based on protein dephosphorylation mediated by the tyrosine phosphatase Ltp1, and converge on a LuxR-family transcriptional regulator, CdhR. Phenotypic responses in P. gingivalis include regulation of hemin uptake systems and gingipain activity, processes that are intimately linked to the virulence of the organism. Furthermore, communities of S. gordonii with P. gingivalis or with A. actinomycetemcomitans are more pathogenic in animal models than the constituent species alone. We propose that MGS should be considered accessory pathogens, organisms whose pathogenic potential only becomes evident in the context of a heterotypic microbial community. © 2011 Blackwell Publishing Ltd.

  17. Dilatancy induced ductile-brittle transition of shear band in metallic glasses

    Science.gov (United States)

    Zeng, F.; Jiang, M. Q.; Dai, L. H.

    2018-04-01

    Dilatancy-generated structural disordering, an inherent feature of metallic glasses (MGs), has been widely accepted as the physical mechanism for the primary origin and structural evolution of shear banding, as well as the resultant shear failure. However, it remains a great challenge to determine, to what degree of dilatation, a shear banding will evolve into a runaway shear failure. In this work, using in situ acoustic emission monitoring, we probe the dilatancy evolution at the different stages of individual shear band in MGs that underwent severely plastic deformation by the controlled cutting technology. A scaling law is revealed that the dilatancy in a shear band is linearly related to its evolution degree. A transition from ductile-to-brittle shear bands is observed, where the formers dominate stable serrated flow, and the latter lead to a runaway instability (catastrophe failure) of serrated flow. To uncover the underlying mechanics, we develop a theoretical model of shear-band evolution dynamics taking into account an atomic-scale deformation process. Our theoretical results agree with the experimental observations, and demonstrate that the atomic-scale volume expansion arises from an intrinsic shear-band evolution dynamics. Importantly, the onset of the ductile-brittle transition of shear banding is controlled by a critical dilatation.

  18. Decentralised control method for DC microgrids with improved current sharing accuracy

    DEFF Research Database (Denmark)

    Yang, Jie; Jin, Xinmin; Wu, Xuezhi

    2017-01-01

    A decentralised control method that deals with current sharing issues in dc microgrids (MGs) is proposed in this study. The proposed method is formulated in terms of ‘modified global indicator’ concept, which was originally proposed to improve reactive power sharing in ac MGs. In this work......, the ‘modified global indicator’ concept is extended to coordinate dc MGs, which aims to preserve the main features offered by decentralised control methods such as no need of communication links, central controller or knowledge of the microgrid topology and parameters. This global indicator is inserted between...... a shunt virtual resistance. The operation under multiple dc-buses is also included in order to enhance the applicability of the proposed controller. A detailed mathematical model including the effect of network mismatches is derived for analysis of the stability of the proposed controller. The feasibility...

  19. Author Details

    African Journals Online (AJOL)

    Cattell, K. Vol 20, No 2 (2013) - Articles Workplace stress experienced by quantity surveyors. Abstract PDF · Vol 20, No 2 (2013) - Articles Harassment and discrimination experienced by quantity surveyors in South Africa Abstract PDF. ISSN: 2415-0487. AJOL African Journals Online. HOW TO USE AJOL... for Researchers ...

  20. Author Details

    African Journals Online (AJOL)

    Bowen, P. Vol 20, No 2 (2013) - Articles Workplace stress experienced by quantity surveyors. Abstract PDF · Vol 20, No 2 (2013) - Articles Harassment and discrimination experienced by quantity surveyors in South Africa Abstract PDF. ISSN: 1023-0564. AJOL African Journals Online. HOW TO USE AJOL... for Researchers ...

  1. Author Details

    African Journals Online (AJOL)

    Edwards, P. Vol 20, No 2 (2013) - Articles Workplace stress experienced by quantity surveyors. Abstract PDF · Vol 20, No 2 (2013) - Articles Harassment and discrimination experienced by quantity surveyors in South Africa Abstract PDF. ISSN: 2415-0487. AJOL African Journals Online. HOW TO USE AJOL... for Researchers ...

  2. Cruise report; RV Coastal Surveyor Cruise C1-99; multibeam mapping of the Long Beach, California continental shelf; April 12 through May 19, 1999

    Science.gov (United States)

    Gardner, James V.; Hughes-Clarke, John E.; Mayer, Larry A.

    1999-01-01

    The greater Los Angeles area of California is home to more than 10 million people. This large population puts increased pressure on the adjacent offshore continental shelf and margin with activities such as ocean disposal for dredged spoils, explosive disposal, waste-water outfall, and commercial fishing. The increased utilization of the shelf and margin in this area has generated accelerated multi-disciplinary research efforts in all aspects of the environment of the coastal zone. Prior to 1996 there were no highly accurate base maps of the continental shelf and slope upon which the research activities could be located and monitored. In 1996, the United States Geological Survey (USGS) Pacific Seafloor Mapping Project began to address this problem by mapping the Santa Monica shelf and margin (Fig. 1) using a state-of-the-art, high-resolution multibeam sonar system (Gardner, et al., 1996; 1999). Additional seafloor mapping in 1998 provided coverage of the continental margin from south of Newport to the proximal San Pedro Basin northwest of Palos Verdes Peninsula (Gardner, et al., 1998) (Fig. 1). The mapping of the seafloor in the greater Los Angeles continental shelf and margin was completed with a 30-day mapping of the Long Beach shelf in April and May 1999, the subject of this report. The objective of Cruise C-1-99-SC was to completely map the broad continental shelf from the eastern end of the Palos Verdes Peninsula to the narrow shelf south of Newport Beach, from the break in slope at about 120-m isobath to the inner shelf at about the 10-m isobath. Mapping the Long Beach shelf was jointly funded by the U.S. Geological Survey and the County of Orange (CA) Sanitation District and was conducted under a Cooperative Agreement with the Ocean Mapping Group from the University of New Brunswick (OMG/UNB). The OMG/UNB contracted with C&C Technologies, Inc. of Lafayette, LA for use of the RV Coastal Surveyor and the latest evolution of high-resolution multibeam sonars, a

  3. Minority games, evolving capitals and replicator dynamics

    International Nuclear Information System (INIS)

    Galla, Tobias; Zhang, Yi-Cheng

    2009-01-01

    We discuss a simple version of the minority game (MG) in which agents hold only one strategy each, but in which their capitals evolve dynamically according to their success and in which the total trading volume varies in time accordingly. This feature is known to be crucial for MGs to reproduce stylized facts of real market data. The stationary states and phase diagram of the model can be computed, and we show that the ergodicity breaking phase transition common for MGs, and marked by a divergence of the integrated response, is present also in this simplified model. An analogous majority game turns out to be relatively void of interesting features, and the total capital is found to diverge in time. Introducing a restraining force leads to a model akin to the replicator dynamics of evolutionary game theory, and we demonstrate that here a different type of phase transition is observed. Finally we briefly discuss the relation of this model with one strategy per player to more sophisticated minority games with dynamical capitals and several trading strategies per agent

  4. De Amsterdamse bouwmeester en landmeter Jan Jacobszoon Bolten (1738-na 1811)

    NARCIS (Netherlands)

    von der Dunk, T.H.

    2013-01-01

    The Amsterdam architect and surveyor Jan Jacobszoon Bolten (1738-after 1811) is one of many private architects whose name pops up now and then in the literature. This essay, for the first time, sketches his quite varied career. Since mid-1768 he held the post of architect and surveyor in the

  5. Ensuring Standards in Geospatial Data | Nwadialor | FUTY Journal ...

    African Journals Online (AJOL)

    Since evolution of modern civilization, land surveyors solely were legally entrusted with the task of geographic data collection for planning and development of any nation. Presently, society has become very complex and so has the high demand of geo-data facing the surveyor. In response to this, technological development ...

  6. Power Flow Analysis for Low-Voltage AC and DC Microgrids Considering Droop Control and Virtual Impedance

    DEFF Research Database (Denmark)

    Li, Chendan; Chaudhary, Sanjay Kumar; Savaghebi, Mehdi

    2017-01-01

    In the low-voltage (LV) ac microgrids (MGs), with a relatively high R/X ratio, virtual impedance is usually adopted to improve the performance of droop control applied to distributed generators (DGs). At the same time, LV dc MG using virtual impedance as droop control is emerging without adequate...... power flow studies. In this paper, power flow analyses for both ac and dc MGs are formulated and implemented. The mathematical models for both types of MGs considering the concept of virtual impedance are used to be in conformity with the practical control of the DGs. As a result, calculation accuracy...... is improved for both ac and dc MG power flow analyses, comparing with previous methods without considering virtual impedance. Case studies are conducted to verify the proposed power flow analyses in terms of convergence and accuracy. Investigation of the impact to the system of internal control parameters...

  7. Relationship between the electronic structure and the glide in the hexagonal close packed metals

    International Nuclear Information System (INIS)

    Legrand, B.; Le Hazif, R.

    1983-06-01

    In all hexagonal close-packed metals (HCP), deformation is performed by slip on a mean glide system (MGS) and on several secondary systems. There are no reliable predictions of the MGS choice. In this paper is shown the role played by the electronic structure on the choice of glide system in HCP metals. MGS is basal for all normal metals and is a function of the electron number in HCP transition metals. The different SFE's were calculated using appropriate total energy models, for different metals. Thus pseudopotentials were used (or empirical pair potentials) for normal metals, and a tight-binding model for transition metals. The most important results are the following: prismatic SFE (PSFE) is smaller than basal SFE (BSFE) for Y, Ti, Zr, Hf, Ru and Os; BSFE is smaller than PSFE for Co and all normal metals; BSFE and PSFe and about the same for RE and Tc

  8. Performance evaluation of microturbine generation system for microgrid applications

    Energy Technology Data Exchange (ETDEWEB)

    Salam, A.A.; Mohamed, A.; Hannan, M.A.; Shareef, H.; Wanik, M.Z.C. [Kebangsaan Malaysia Univ., Selangor (Malaysia). Dept. of Electrical, Electronic and Systems Engineering, Faculty of Engineering and Built Environment

    2009-03-11

    A control system for microturbine generation system (MGS) units in microgrid applications was presented. A dynamic model of the microturbine and power electronics interface systems was used to determine converter control strategies for distributed generation operation. Back-to-back converters were used to interface the microturbine-based distributed generation system to the grid. The controllers were used to regulate the output voltage value at the reference bus voltage and the frequency of the whole grid. Reference values were predetermined in the control scheme in order to obtain the desired value of voltage amplitude and frequency. An investigation of system dynamics was conducted using simulations in both grid-connected and islanded modes. Results of the simulations demonstrated the ability of the MGS to improve electricity grid reliability. The model can be used to accurately simulate MGS dynamic performance for both grid- and islanded modes of operation. 10 refs., 17 figs.

  9. Model comparison on genomic predictions using high-density markers for different groups of bulls in the Nordic Holstein population

    DEFF Research Database (Denmark)

    Gao, Hongding; Su, Guosheng; Janss, Luc

    2013-01-01

    This study compared genomic predictions based on imputed high-density markers (~777,000) in the Nordic Holstein population using a genomic BLUP (GBLUP) model, 4 Bayesian exponential power models with different shape parameters (0.3, 0.5, 0.8, and 1.0) for the exponential power distribution...... relationship with the training population. Groupsmgs had both the sire and the maternal grandsire (MGS), Groupsire only had the sire, Groupmgs only had the MGS, and Groupnon had neither the sire nor the MGS in the training population. Reliability of DGV was measured as the squared correlation between DGV...... and DRP divided by the reliability of DRP for the bulls in validation data set. Unbiasedness of DGV was measured as the regression of DRP on DGV. The results indicated that DGV were more accurate and less biased for animals that were more related to the training population. In general, the Bayesian...

  10. Simulating the Current Water Cycle with the NASA Ames Mars Global Climate Model

    Science.gov (United States)

    Kahre, M. A.; Haberle, R. M.; Hollingsworth, J. L.; Brecht, A. S.; Urata, R. A.; Montmessin, F.

    2017-12-01

    The water cycle is a critical component of the current Mars climate system, and it is now widely recognized that water ice clouds significantly affect the nature of the simulated water cycle. Two processes are key to implementing clouds in a Mars global climate model (GCM): the microphysical processes of formation and dissipation, and their radiative effects on atmospheric heating/cooling rates. Together, these processes alter the thermal structure, change the atmospheric dynamics, and regulate inter-hemispheric transport. We have made considerable progress using the NASA Ames Mars GCM to simulate the current-day water cycle with radiatively active clouds. Cloud fields from our baseline simulation are in generally good agreement with observations. The predicted seasonal extent and peak IR optical depths are consistent MGS/TES observations. Additionally, the thermal response to the clouds in the aphelion cloud belt (ACB) is generally consistent with observations and other climate model predictions. Notably, there is a distinct gap in the predicted clouds over the North Residual Cap (NRC) during local summer, but the clouds reappear in this simulation over the NRC earlier than the observations indicate. Polar clouds are predicted near the seasonal CO2 ice caps, but the column thicknesses of these clouds are generally too thick compared to observations. Our baseline simulation is dry compared to MGS/TES-observed water vapor abundances, particularly in the tropics and subtropics. These areas of disagreement appear to be a consistent with other current water cycle GCMs. Future avenues of investigation will target improving our understanding of what controls the vertical extent of clouds and the apparent seasonal evolution of cloud particle sizes within the ACB.

  11. Multi-Scale Modeling of Microstructural Evolution in Structural Metallic Systems

    Science.gov (United States)

    Zhao, Lei

    the attachment behavior takes place collectively and heterogeneously, similarly to Al diffusion in MGs. Finally, we applied the MD technique to study the origin of five-fold twinning nucleation during the solidification of Al base alloys. We studied several model alloys and reported the observed nucleation pathway. We found that the key factors controlling the five-fold twinning are the twin boundary energy and the formation of pentagon structures, and the twin boundary energy plays the dominant role in the five-fold twinning in the model alloys studied.

  12. Síndrome de Cushing por adenomielolipoma. Presentación de caso Cushing's syndrome caused by adenomyelolipoma. A case report

    Directory of Open Access Journals (Sweden)

    Idania Teresa Mora López

    2012-04-01

    Full Text Available Se presenta el caso de una paciente de 61 años con antecedentes de dolor lumbar derecho con una irradiación al miembro inferior derecho que no se alivia con el reposo, ni analgésicos, de moderada intensidad, y 3 meses de evolución, debuta de hipertensión arterial, diabetes mellitus e incremento del peso corporal en la cara, tórax y abdomen, que contrasta con delgadez de las extremidades. Se decide el ingreso, siendo realizadas investigaciones indispensables, donde se demuestran las cifras de glucemia compatibles con diabetes mellitus, estudios imagenológicos, como la ultrasonografía de hemiabdomen superior donde se observa masa suprarrenal derecha en contacto con el hígado, tomografía axial computarizada simple y contrastada de suprarrenales que confirma resultado ultrasonográfico, ante esto se le realiza ritmo circadiano para el cortisol, que no se encontraba conservado, inhibiciones con 2 mgs y 8mgs de dexametasona, no existiendo inhibición, confirmándose síndrome de Cushing. Se decide adrenalectomía derecha y biopsia por congelación, que informa adenomielolipoma de 7 cms x 6 cms de suprarrenal derecha.A 61-year old female patient with a history of right back pain with radiation to the right-lower limb, that did not relieve at rest or with the use analgesics of moderate intensity, having a 3-month evolution, presenting hypertension and diabetes mellitus onset, together with an increase in body weight mainly in her face, thorax and abdomen, which contrasted to the thinness of her extremities was admitted. The necessary clinical complementaries indicated high levels of blood glucose compatible with diabetes mellitus and the sonographic studies showed an adrenal mass in contact with the liver in the upper right hemi-abdomen, simple and contrasted CT of the adrenal glands confirmed the sonographic results, the circadian rhythm was driven to the cortisol control, resulting in not preserved. No inhibitions were observed with 2 mgs

  13. [Safety and effectiveness of nicotinic acid in the management of patients with chronic renal disease and hyperlipidemia associated to hyperphosphatemia].

    Science.gov (United States)

    Restrepo Valencia, C A; Cruz, J

    2008-01-01

    To establish if the nicotinic acid in patients with chronic renal disease reduce significantly and with security the levels of lipids and serum phosphate in refractory patients to the classical management. Observational study Place: Renal Unity RTS Ltda Caldas Santa Sofìa Hospital. All the patients with chronic renal disease in dialysis therapy to whom the classical treatment for their hyperlipidaemia and hyperphosphatemia didn't manage a satisfactory reduce of their serum levels. It was identified that those patients who in the 3 previous months to the intervention hadn't presented changes in the lipids profile even though they received low fats diet and a lipid lowering therapies (statin o fibric acid derivates). It was determined in them whether they presented levels of serum phosphorus greater than 5.5 mg/dl even though having received nutritional recommendations and treatment with oral phosphate binding agents (Aluminum hydroxide, Calcium salts or Sevelamer). In them it was proceeded to administrate nicotinic acid via oral at night until a doses of 1,000 milligrams was reached (preceded of 100 mgs of acetylsalicylic acid 1 hour before) during a period of 8 months, observing its therapeutical effectivity and security profile to improve the lipids profile and reduce the serum phosphorus. 9 patients complied with the requirements, average time in dialysis 34 months, 3 in hemodialysis and 6 in peritoneal dialysis. All patients started with 500 mgs and 3 months later correctly tolerated the dose of 1,000 mgs. Between the evaluated variables, the most important changes were: the phosphorus reduced reaching a significant value at eight months: initial 6.46+/-0.53, four months 4.37+/-0.63 (p>0.05) and eight months 3.94+/-0.76 (padherence to the medicament 100%. The nicotinic acid is efficient, very well tolerated and economical in comparison with others drugs, which makes it ideal for the treatment of patients with hyperlipidaemia and refractory hyperphosphatemia to

  14. The Effect of Cooling Conditions on the Evolution of Non-metallic Inclusions in High Manganese TWIP Steels

    Science.gov (United States)

    Wang, Yu-Nan; Yang, Jian; Xin, Xiu-Ling; Wang, Rui-Zhi; Xu, Long-Yun

    2016-04-01

    In the present study, the effect of cooling conditions on the evolution of non-metallic inclusions in high manganese TWIP steels was investigated based on experiments and thermodynamic calculations. In addition, the formation and growth behavior of AlN inclusions during solidification under different cooling conditions were analyzed with the help of thermodynamics and dynamics. The inclusions formed in the high manganese TWIP steels are classified into nine types: (1) AlN; (2) MgO; (3) CaS; (4) MgAl2O4; (5) AlN + MgO; (6) MgO + MgS; (7) MgO + MgS + CaS; (8) MgO + CaS; (9) MgAl2O4 + MgS. With the increase in the cooling rate, the volume fraction and area ratio of inclusions are almost constant; the size of inclusions decreases and the number density of inclusions increases in the steels. The thermodynamic results of inclusion types calculated with FactSage are consistent with the observed results. With increasing cooling rate, the diameter of AlN decreases. When the cooling rate increases from 0.75 to 4.83 K s-1, the measured average diameter of AlN decreases from 4.49 to 2.42 μm. Under the high cooling rate of 4.83 K s-1, the calculated diameter of AlN reaches 3.59 μm at the end of solidification. However, the calculated diameter of AlN increases to approximately 5.93 μm at the end of solidification under the low cooling rate of 0.75 K s-1. The calculated diameter of AlN decreases with increasing cooling rate. The theoretical calculation results of the change in diameter of AlN under the different cooling rates have the same trend with the observed results. The existences of inclusions in the steels, especially AlN which average sizes are 2.42 and 4.49 μm, respectively, are not considered to have obvious influences on the hot ductility.

  15. Comparative proteomic analysis provides insight into 10-hydroxy-2-decenoic acid biosynthesis in honey bee workers.

    Science.gov (United States)

    Yang, Xiao-Hui; Yang, Shi-Fa; Wang, Rui-Ming

    2017-07-01

    10-Hydroxy-2-decenoic acid (10-HDA) is the major compound produced from the mandibular glands (MGs) of honey bee workers. However, little information is available on the molecular mechanisms of 10-HDA biosynthesis. In our study, based on investigating the 10-HDA secretion pattern and the morphological characteristics of MGs from honey bee workers of different ages, a comparative proteomic analysis was performed in the MGs of workers with different 10-HDA production. In total, 59 up-regulated protein species representing 45 unique proteins were identified in high 10-HDA-producing workers by 2-DE-MALDI-TOF/TOF MS. These proteins were involved in carbohydrate/energy metabolism, fatty acid metabolism, protein metabolism and folding, antioxidation, cytoskeleton, development and cell signaling. Proteins related to fatty acid metabolism, including fatty acid synthase and β-oxidation enzymes, are potentially crucial proteins involved in 10-HDA biosynthesis pathway. And RNA interference (RNAi) results demonstrated that knockdown of electron transfer flavoprotein subunit beta (ETF-β), one of the protein related to fatty acid metabolism, decreased 10-HDA production of worker bees, suggesting that ETF-β was necessary for 10-HDA biosynthesis. This study reveals the characteristics of MGs of worker bees at different developmental stages and proteins associated with 10-HDA biosynthesis, which provides the first insight into the molecular mechanism of 10-HDA biosynthesis.

  16. Multi-Functional Distributed Secondary Control for Autonomous Microgrids

    DEFF Research Database (Denmark)

    Shafiee, Qobad

    Microgrids (MGs)--the building blocks of the smart grid-- are local grids comprise different technologies such as power electronics converters, distributed renewable and non-renewable energy sources, energy storage systems, and telecommunications which can operate either in islanded mode or conne......Microgrids (MGs)--the building blocks of the smart grid-- are local grids comprise different technologies such as power electronics converters, distributed renewable and non-renewable energy sources, energy storage systems, and telecommunications which can operate either in islanded mode...

  17. Contribution to the study of the intergalactic medium physical properties through infrared, sub-millimetric and millimetric observations

    International Nuclear Information System (INIS)

    Pointecouteau, Etienne

    1999-01-01

    This work concerns the largest self-gravitating structures of the Universe, clusters of galaxies. Due to its thermodynamical conditions, their intracluster atmosphere is completely ionised. This gas is observed at X-ray wavelengths through its free-free emission, and at submillimeter-millimeter wavelengths through the Sunyaev-Zel'dovich (SZ) effect. This effect is due to the inverse Compton scattering of the cosmic microwave background photons by the hot intracluster electrons. First, taking into account the weakly relativistic behaviour of the electrons, we performed exact calculations of the SZ spectrum. The resulting spectra show the strong dependency of the SZ effect spectral shape with respect to the gas temperature. Making use of this work, we analysed the millimeter data from the DiaBolo spectrophotometer in the direction of a massive and distant cluster, RXJ1347-1145. With a high angular resolution, we have mapped the centre and the extended emission of this cluster, leading to the detection of the strongest SZ effect measured to date. The comparison with the X-ray data shows some very exciting and puzzling differences. In the third part, we present for the first time the spectrum of a galaxy cluster, A2163, from far infrared (90 μm) to millimeter (2.1 mm) wavelengths. The constraints set by the FIR measurements on the residual dust emission, allowed us put strong constraints on the SZ parameters. Finally, we propose a new method which allows to extract the intracluster gas temperature from a set of SZ data. We have quantified the reliability of this method in case of observations obtained from the Planck surveyor and the Herschel space missions. (author) [fr

  18. White Rock

    Science.gov (United States)

    2002-01-01

    (Released 19 April 2002) The Science 'White Rock' is the unofficial name for this unusual landform which was first observed during the Mariner 9 mission in the early 1970's. As later analysis of additional data sets would show, White Rock is neither white nor dense rock. Its apparent brightness arises from the fact that the material surrounding it is so dark. Images from the Mars Global Surveyor MOC camera revealed dark sand dunes surrounding White Rock and on the floor of the troughs within it. Some of these dunes are just apparent in the THEMIS image. Although there was speculation that the material composing White Rock could be salts from an ancient dry lakebed, spectral data from the MGS TES instrument did not support this claim. Instead, the White Rock deposit may be the erosional remnant of a previously more continuous occurrence of air fall sediments, either volcanic ash or windblown dust. The THEMIS image offers new evidence for the idea that the original deposit covered a larger area. Approximately 10 kilometers to the southeast of the main deposit are some tiny knobs of similarly bright material preserved on the floor of a small crater. Given that the eolian erosion of the main White Rock deposit has produced isolated knobs at its edges, it is reasonable to suspect that the more distant outliers are the remnants of a once continuous deposit that stretched at least to this location. The fact that so little remains of the larger deposit suggests that the material is very easily eroded and simply blows away. The Story Fingers of hard, white rock seem to jut out like icy daggers across a moody Martian surface, but appearances can be deceiving. These bright, jagged features are neither white, nor icy, nor even hard and rocky! So what are they, and why are they so different from the surrounding terrain? Scientists know that you can't always trust what your eyes see alone. You have to use other kinds of science instruments to measure things that our eyes can

  19. Inhibitory effect of etodolac, a selective cyclooxygenase-2 inhibitor, on stomach carcinogenesis in Helicobacter pylori-infected Mongolian gerbils

    International Nuclear Information System (INIS)

    Magari, Hirohito; Shimizu, Yasuhito; Inada, Ken-ichi; Enomoto, Shotaro; Tomeki, Tatsuji; Yanaoka, Kimihiko; Tamai, Hideyuki; Arii, Kenji; Nakata, Hiroya; Oka, Masashi; Utsunomiya, Hirotoshi; Tsutsumi, Yutaka; Tsukamoto, Tetsuya; Tatematsu, Masae; Ichinose, Masao

    2005-01-01

    The effect of the selective COX-2 inhibitor, etodolac, on Helicobacter pylori (Hp)-associated stomach carcinogenesis was investigated in Mongolian gerbils (MGs). Hp-infected MGs were fed for 23 weeks with drinking water containing 10 ppm N-methyl-N-nitrosourea. They were then switched to distilled water and placed on a diet containing 5-30 mg/kg/day etodolac for 30 weeks. We found that etodolac dose-dependently inhibited the development of gastric cancer, and no cancer was detected at a dose of 30 mg/kg/day. Etodolac did not affect the extent of inflammatory cell infiltration or oxidative DNA damage, but it significantly inhibited mucosal cell proliferation and dose-dependently repressed the development of intestinal metaplasia in the stomachs of Hp-infected MGs. These results suggest that COX-2 is a key molecule in inflammation-mediated stomach carcinogenesis and that chemoprevention of stomach cancer should be possible by controlling COX-2 expression or activity

  20. FACTORS INFLUENCING YIELD SPREADS OF THE MALAYSIAN BONDS

    Directory of Open Access Journals (Sweden)

    Norliza Ahmad

    2009-01-01

    Full Text Available Malaysian bond market is developing rapidly but not much is understood in terms of macroeconomic factors that could influence the yield spread of the Ringgit Malaysian denominated bonds. Based on a multifactor model, this paper examines the impact of four macroeconomic factors namely: Kuala Lumpur Composite Index (KLCI, Industry Production Index (IPI, Consumer Price Index (CPI and interest rates (IR on bond yield spread of the Malaysian Government Securities (MGS and Corporate Bonds (CBs for a period from January 2001 to December 2008. The findings support the expected hypotheses that CPI and IR are the major drivers that influence the changes in MGS yield spreads. However IPI and KLCI have weak and no influence on MGS yield spreads respectively Whilst IR, CPI and IPI have significant influence on the yield spreads of CB1, CB2 and CB3, KLCI has significant influence only on the CB1 yield spread but not on CB2 and CB3 yield spreads.

  1. Meckel-Gruber Syndrome: Autopsy Based Approach to Diagnosis

    Directory of Open Access Journals (Sweden)

    Asaranti Kar

    2016-01-01

    Full Text Available Meckel-Gruber syndrome (MGS is a rare lethal congenital malformation affecting 1 in 13,250-140,000 live births. The classical diagnostic triad comprises multicystic dysplastic kidneys, occipital encephalocele, and postaxial polydactyly. It can variably be associated with other malformations such as cleft lip and palate, pulmonary hypoplasia, hepatic fibrosis, and anomalies of central nervous system. A 20 weeks fetus was diagnosed as MGS with classical features along with many other congenital abnormalities such as microcephaly, microphthalmia, hypertelorism, cleft lip and palate, neonatal teeth, and the right side club foot which were detected only after doing autopsy. This case is reported because of its rarity emphasizing the importance of neonatal autopsy in every case of fetal death, especially where the antenatal diagnosis has not been made previously. A systematic approach to accurate diagnosis of MGS based on autopsy will be described here which can allow recurrence risk counseling and proper management in future pregnancies.

  2. SNP Discovery for mapping alien introgressions in wheat

    Science.gov (United States)

    2014-01-01

    Background Monitoring alien introgressions in crop plants is difficult due to the lack of genetic and molecular mapping information on the wild crop relatives. The tertiary gene pool of wheat is a very important source of genetic variability for wheat improvement against biotic and abiotic stresses. By exploring the 5Mg short arm (5MgS) of Aegilops geniculata, we can apply chromosome genomics for the discovery of SNP markers and their use for monitoring alien introgressions in wheat (Triticum aestivum L). Results The short arm of chromosome 5Mg of Ae. geniculata Roth (syn. Ae. ovata L.; 2n = 4x = 28, UgUgMgMg) was flow-sorted from a wheat line in which it is maintained as a telocentric chromosome. DNA of the sorted arm was amplified and sequenced using an Illumina Hiseq 2000 with ~45x coverage. The sequence data was used for SNP discovery against wheat homoeologous group-5 assemblies. A total of 2,178 unique, 5MgS-specific SNPs were discovered. Randomly selected samples of 59 5MgS-specific SNPs were tested (44 by KASPar assay and 15 by Sanger sequencing) and 84% were validated. Of the selected SNPs, 97% mapped to a chromosome 5Mg addition to wheat (the source of t5MgS), and 94% to 5Mg introgressed from a different accession of Ae. geniculata substituting for chromosome 5D of wheat. The validated SNPs also identified chromosome segments of 5MgS origin in a set of T5D-5Mg translocation lines; eight SNPs (25%) mapped to TA5601 [T5DL · 5DS-5MgS(0.75)] and three (8%) to TA5602 [T5DL · 5DS-5MgS (0.95)]. SNPs (gsnp_5ms83 and gsnp_5ms94), tagging chromosome T5DL · 5DS-5MgS(0.95) with the smallest introgression carrying resistance to leaf rust (Lr57) and stripe rust (Yr40), were validated in two released germplasm lines with Lr57 and Yr40 genes. Conclusion This approach should be widely applicable for the identification of species/genome-specific SNPs. The development of a large number of SNP markers will facilitate the precise introgression and

  3. SNP Discovery for mapping alien introgressions in wheat.

    Science.gov (United States)

    Tiwari, Vijay K; Wang, Shichen; Sehgal, Sunish; Vrána, Jan; Friebe, Bernd; Kubaláková, Marie; Chhuneja, Praveen; Doležel, Jaroslav; Akhunov, Eduard; Kalia, Bhanu; Sabir, Jamal; Gill, Bikram S

    2014-04-10

    Monitoring alien introgressions in crop plants is difficult due to the lack of genetic and molecular mapping information on the wild crop relatives. The tertiary gene pool of wheat is a very important source of genetic variability for wheat improvement against biotic and abiotic stresses. By exploring the 5Mg short arm (5MgS) of Aegilops geniculata, we can apply chromosome genomics for the discovery of SNP markers and their use for monitoring alien introgressions in wheat (Triticum aestivum L). The short arm of chromosome 5Mg of Ae. geniculata Roth (syn. Ae. ovata L.; 2n = 4x = 28, UgUgMgMg) was flow-sorted from a wheat line in which it is maintained as a telocentric chromosome. DNA of the sorted arm was amplified and sequenced using an Illumina Hiseq 2000 with ~45x coverage. The sequence data was used for SNP discovery against wheat homoeologous group-5 assemblies. A total of 2,178 unique, 5MgS-specific SNPs were discovered. Randomly selected samples of 59 5MgS-specific SNPs were tested (44 by KASPar assay and 15 by Sanger sequencing) and 84% were validated. Of the selected SNPs, 97% mapped to a chromosome 5Mg addition to wheat (the source of t5MgS), and 94% to 5Mg introgressed from a different accession of Ae. geniculata substituting for chromosome 5D of wheat. The validated SNPs also identified chromosome segments of 5MgS origin in a set of T5D-5Mg translocation lines; eight SNPs (25%) mapped to TA5601 [T5DL · 5DS-5MgS(0.75)] and three (8%) to TA5602 [T5DL · 5DS-5MgS (0.95)]. SNPs (gsnp_5ms83 and gsnp_5ms94), tagging chromosome T5DL · 5DS-5MgS(0.95) with the smallest introgression carrying resistance to leaf rust (Lr57) and stripe rust (Yr40), were validated in two released germplasm lines with Lr57 and Yr40 genes. This approach should be widely applicable for the identification of species/genome-specific SNPs. The development of a large number of SNP markers will facilitate the precise introgression and monitoring of alien segments in crop

  4. Outcomes of different Class II treatments : Comparisons using the American Board of Orthodontics Model Grading System.

    Science.gov (United States)

    Akinci Cansunar, Hatice; Uysal, Tancan

    2016-07-01

    The aim of this study was to evaluate the clinical outcomes of three different Class II treatment modalities followed by fixed orthodontic therapy, using the American Board of Orthodontics Model Grading System (ABO-MGS). As a retrospective study, files of patients treated at postgraduate orthodontic  clinics in different cities in Turkey was randomly selected. From 1684 posttreatment records, 669 patients were divided into three groups: 269 patients treated with extraction of two upper premolars, 198 patients treated with cervical headgear, and 202 patients treated with functional appliances. All the cases were evaluated by one researcher using ABO-MGS. The χ (2), Z test, and multivariate analysis of variance were used for statistical evaluation (p < 0.05). No significant differences were found among the groups in buccolingual inclination, overjet, occlusal relationship, and root angulation. However, there were significant differences in alignment, marginal ridge height, occlusal contact, interproximal contact measurements, and overall MGS average scores. The mean treatment time between the extraction and functional appliance groups was significantly different (p = 0.017). According to total ABO-MGS scores, headgear treatment had better results than functional appliances. The headgear group had better tooth alignment than the extraction group. Headgear treatment resulted in better occlusal contacts than the functional appliances and had lower average scores for interproximal contact measurements. Functional appliances had the worst average scores for marginal ridge height. Finally, the functional appliance group had the longest treatment times.

  5. Up-conversion and near infrared luminescence in Er3+/Yb3+ co-doped glass-ceramic containing MgGa2O4 nano-crystals

    International Nuclear Information System (INIS)

    Sun, Jiaju; Yu, Lixin; Li, Fuhai; Wei, Shuilin; Li, Songchu

    2016-01-01

    The MgO–Ga 2 O 3 –SiO 2 (MG-S) glasses and nanocrystalline glass-ceramics (GCs) containing MgGa 2 O 4 nanocrystals codoped with Er 3+ and Yb 3+ were prepared by a simple sol–gel method. The formation of MgGa 2 O 4 nanocrystals in the GCs was confirmed by the X-ray diffraction (XRD). Their morphology was investigated applying high-resolution transmission electron microscopy (HRTEM). Stark splitting of near infrared (NIR) and up-conversion (UC) emission implies that the Er 3+ is incorporated into MgGa 2 O 4 nanocrystals. The effect of the MgO, Ga 2 O 3 content and sintering temperature on the structure of the prepared samples was systematically studied. Under 980 nm excitation, intense UC and NIR emission (1530 nm) were observed in the MG-S GCs by efficient energy transfer from Yb 3+ to Er 3+ . The two-photon process was confirmed to be responsible for both the green and red UC emissions. - Highlights: • It is interesting that the CIE chromaticity coordinates of the several prepared CaMO 4 :Eu samples by a hydrothermal method are very close to the standard of white light.

  6. Impact of spatial dimension on structural ordering in metallic glass.

    Science.gov (United States)

    Hu, Yuan-Chao; Tanaka, Hajime; Wang, Wei-Hua

    2017-08-01

    Metallic glasses (MGs) have so far attracted considerable attention for their applications as bulk materials. However, new physics and applications often emerge by dimensional reduction from three dimensions (3D) to two dimensions (2D). Here, we study, by molecular dynamics simulations, how the liquid-to-glass transition of a binary Cu_{50}Zr_{50} MG is affected by spatial dimensionality. We find clear evidence that crystal-like structural ordering controls both dynamic heterogeneity and slow dynamics, and thus plays a crucial role in the formation of the 2DMG. Although the 2DMG reproduces the dynamical behaviors of its 3D counterpart by considering Mermin-Wagner-type fluctuations specific to 2D, this atomic-scale structural mechanism is essentially different from that for the 3DMG in which icosahedral clusters incompatible with crystallographic symmetry play a key role in glassy behaviors. Our finding provides a structural mechanism for the formation of 2DMGs, which cannot be inferred from the knowledge of 3DMGs. The results suggest a structural basis for the glass transition in 2DMG and provide possible explanations for some previous experimental observations in ultrathin film MGs.

  7. Atomic Scale Investigation of Structural Properties and Glass Forming Ability of Ti100- x Al x Metallic Glasses

    Science.gov (United States)

    Tahiri, M.; Hasnaoui, A.; Sbiaai, K.

    2018-06-01

    In this work, we employed molecular dynamics (MD) simulations to study Ti-Al metallic glasses (MGs) using the embedded atom method (EAM) potential to model the atomic interaction with different compositions. The results showed evidence of the metallic glass formation induced by the split occurring in the second peak of the radial distribution function (RDF) curves implying both Ti and Al atoms. The common neighbor analysis (CNA) method confirmed the presence of the icosahedral clusters with a maximum amount observed for an alloy with 75 pct of Al. Analysis of coordination numbers (CNs) indicated that the total CNs are nearly unchanged in these systems. Finally, Voronoi tessellation analyses (VTA) showed a higher value of the number of icosahedral units at Ti25Al75 composition. This specific composition represents a nearby peritectic point localized at a low melting point in the Ti-Al binary phase diagram. The glass forming ability (GFA) becomes important when the fraction of Al increases by forming and connecting "icosahedral-like" clusters (12-coordinated and 13-coordinated ) and by playing a main role in the structure stability of the Ti-Al MGs.

  8. Atomic Scale Investigation of Structural Properties and Glass Forming Ability of Ti100-x Al x Metallic Glasses

    Science.gov (United States)

    Tahiri, M.; Hasnaoui, A.; Sbiaai, K.

    2018-03-01

    In this work, we employed molecular dynamics (MD) simulations to study Ti-Al metallic glasses (MGs) using the embedded atom method (EAM) potential to model the atomic interaction with different compositions. The results showed evidence of the metallic glass formation induced by the split occurring in the second peak of the radial distribution function (RDF) curves implying both Ti and Al atoms. The common neighbor analysis (CNA) method confirmed the presence of the icosahedral clusters with a maximum amount observed for an alloy with 75 pct of Al. Analysis of coordination numbers (CNs) indicated that the total CNs are nearly unchanged in these systems. Finally, Voronoi tessellation analyses (VTA) showed a higher value of the number of icosahedral units at Ti25Al75 composition. This specific composition represents a nearby peritectic point localized at a low melting point in the Ti-Al binary phase diagram. The glass forming ability (GFA) becomes important when the fraction of Al increases by forming and connecting "icosahedral-like" clusters (12-coordinated and 13-coordinated ) and by playing a main role in the structure stability of the Ti-Al MGs.

  9. New opportunity for enzymatic modification of fats and oils with industrial potentials

    DEFF Research Database (Denmark)

    Guo, Zheng; Xu, Xuebing

    2005-01-01

    Novozym 435 (Candida antarctica lipase)-catalyzed glycerolysis of commercial oils and fats to produce monoglycerides (MGs) was investigated using a tetraammonium-based ionic liquid (IL) as a reaction medium. A 90% yield of MGs and nearly 100% conversion of triglycerides in this ionic liquid were...... achieved, markedly higher than in normal solvents. The amphiphilic structure of cocosalkyl pentaethoxi methyl ammonium methosulfate (CPMA·MS) was suggested to be capable of creating a compatible system for glycerol, oils and fats, as well as inducing the shift of reaction equilibrium to the formation of MG...

  10. Distributed Smart Decision-Making for a Multimicrogrid System Based on a Hierarchical Interactive Architecture

    DEFF Research Database (Denmark)

    Marzband, Mousa; Parhizi, Narges; Savaghebi, Mehdi

    2016-01-01

    In this paper, a comprehensive real-time interactive EMS framework for the utility and multiple electrically-coupled MGs is proposed. A hierarchical bi-level control scheme-BLCS with primary and secondary level controllers is applied in this regard. The proposed hierarchical architecture consists...... are treated as uncertainties in the proposed structure. In order to handle the uncertainties, Taguchi0s orthogonal array testing-TOAT approach is utilized. Then, the shortage or surplus of the MGs power should be submitted to a central EMS-CEMS in the secondary-level. In order to validate the proposed control...

  11. Potential and Benefits of Building Information Modeling (BIM) During Pre-Construction, Construction and Post Construction Stage

    OpenAIRE

    Aw Nien Wei; Md Azree Othuman Mydin

    2017-01-01

    The construction industry is the main economic support for all countries around the world in which continually adapting to meet competitive challenges around the global market. Nevertheless, the construction project is becoming much more complex and difficult to manage. This is because the construction project involves a large number of stakeholder, for example, the consultant companies, architects, engineers, building surveyors and quantity surveyors. The technology current...

  12. Application of Wireless Sensor and Actuator Networks to Achieve Intelligent Microgrids: A Promising Approach towards a Global Smart Grid Deployment

    Directory of Open Access Journals (Sweden)

    Alvaro Llaria

    2016-02-01

    Full Text Available Smart Grids (SGs constitute the evolution of the traditional electrical grid towards a new paradigm, which should increase the reliability, the security and, at the same time, reduce the costs of energy generation, distribution and consumption. Electrical microgrids (MGs can be considered the first stage of this evolution of the grid, because of the intelligent management techniques that must be applied to assure their correct operation. To accomplish this task, sensors and actuators will be necessary, along with wireless communication technologies to transmit the measured data and the command messages. Wireless Sensor and Actuator Networks (WSANs are therefore a promising solution to achieve an intelligent management of MGs and, by extension, the SG. In this frame, this paper surveys several aspects concerning the application of WSANs to manage MGs and the electrical grid, as well as the communication protocols that could be applied. The main concerns regarding the SG deployment are also presented, including future scenarios where the interoperability of different generation technologies must be assured.

  13. Morning glory syndrome associated with primary open angle glaucoma: Case report

    Directory of Open Access Journals (Sweden)

    Božić Marija

    2014-01-01

    Full Text Available Introduction. Morning glory syndrome (MGS is a rare congenital optic disc anomaly, first reported in 1970. MGS is a nonprogressive and untreatable condition, which usually occurs as an isolated ocular anomaly, and can be associated with the increased incidence of nonrhegmatogenous retinal detachment, and also with strabismus, afferent pupillary defect, visual field defects, presence of hyaloids artery remnants, ciliary body cyst, congenital cataract, lid hemangioma and preretinal gliosis. Case Outline. We report a clinical case of MGS associated with primary open angle glaucoma. The use of sophisticated diagnostic tools, such as retinal tomography and visual field testing is limited if multiple eye conditions are present, since optic disc does not have “usual” appearance that can be analyzed according to standard statistical databases. Conclusion. In treating and follow up of glaucoma cases associated with other diseases and conditions that affect the appearance and function of the optic nerve head, sometimes the use of modern technological methods is limited due to difficult interpretation of the obtained results.

  14. A hidden variable in shear transformation zone volume versus Poisson's ratio relation in metallic glasses

    Science.gov (United States)

    Kim, S. Y.; Oh, H. S.; Park, E. S.

    2017-10-01

    Herein, we elucidate a hidden variable in a shear transformation zone (STZ) volume (Ω) versus Poisson's ratio (ν) relation and clarify the correlation between STZ characteristics and the plasticity of metallic glasses (MGs). On the basis of cooperative shear model and atomic stress theories, we carefully formulate Ω as a function of molar volume (Vm) and ν. The twofold trend in Ω and ν is attributed to a relatively large variation of Vm as compared to that of ν as well as an inverse relation between Vm and ν. Indeed, the derived equation reveals that the number of atoms in an STZ instead of Ω is a microstructural characteristic which has a close relationship with plasticity since it reflects the preference of atomistic behaviors between cooperative shearing and the generation of volume strain fluctuation under stress. The results would deepen our understanding of the correlation between microscopic behaviors (STZ activation) and macroscopic properties (plasticity) in MGs and enable a quantitative approach in associating various STZ-related macroscopic behaviors with intrinsic properties of MGs.

  15. Quantifying multipartite nonlocality via the size of the resource

    Science.gov (United States)

    Curchod, Florian John; Gisin, Nicolas; Liang, Yeong-Cherng

    2015-01-01

    The generation of (Bell-)nonlocal correlations, i.e., correlations leading to the violation of a Bell-like inequality, requires the usage of a nonlocal resource, such as an entangled state. When given a correlation (a collection of conditional probability distributions) from an experiment or from a theory, it is desirable to determine the extent to which the participating parties would need to collaborate nonlocally for its (re)production. Here, we propose to achieve this via the minimal group size (MGS) of the resource, i.e., the smallest number of parties that need to share a given type of nonlocal resource for the above-mentioned purpose. In addition, we provide a general recipe—based on the lifting of Bell-like inequalities—to construct MGS witnesses for nonsignaling resources starting from any given ones. En route to illustrating the applicability of this recipe, we also show that when restricted to the space of full-correlation functions, nonsignaling resources are as powerful as unconstrained signaling resources. Explicit examples of correlations where their MGS can be determined using this recipe and other numerical techniques are provided.

  16. Plane and geodetic surveying

    CERN Document Server

    Johnson, Aylmer

    2014-01-01

    IntroductionAim And ScopeClassification Of SurveysThe Structure Of This BookGeneral Principles Of SurveyingErrorsRedundancyStiffnessAdjustmentPlanning And Record KeepingPrincipal Surveying ActivitiesEstablishing Control NetworksMappingSetting OutResectioningDeformation MonitoringAngle MeasurementThe Surveyor's CompassThe ClinometerThe Total StationMaking ObservationsChecks On Permanent AdjustmentsDistance MeasurementGeneralTape MeasurementsOptical Methods (Tachymetry)Electromagnetic Distance Measurement (EDM)Ultrasonic MethodsGNSSLevellingTheoryThe InstrumentTechniqueBookingPermanent Adjustmen

  17. Intracellular magnesium concentrations in dogs with gastric dilatation-volvulus.

    Science.gov (United States)

    Bebchuk, T N; Hauptman, J G; Braselton, W E; Walshaw, R

    2000-11-01

    To quantify and compare intracellular magnesium concentrations (Mgi) in clinically normal dogs (control dogs) and dogs that have gastric dilatation-volvulus (GDV dogs) and to determine whether there is a difference in Mgi and serum magnesium concentrations (Mgs) between GDV dogs with and without cardiac arrhythmias. 41 control dogs and 21 GDV dogs. Rectus abdominis muscle specimens were obtained from control and GDV dogs for determination of Mgi. Blood samples were obtained from GDV dogs for determination of Mgs, and dogs were monitored for 48 hours for cardiac arrhythmias. Muscle specimens were frozen at -40 C, oven dried at 95 C, and digested with concentrated nitric acid. Multielemental analyses were performed by simultaneous/sequential inductively coupled plasma-atomic emission spectroscopy with fixed-cross flow nebulization. The Mg, was standardized to sulfur content to correct for the amount of fat and fascia in the muscle specimen. Mean (+/- SEM) values were recorded in parts per million (ppm). Results-There were no significant differences in Mgi between control (627 +/- 11.1 ppm) and GDV (597 +/- 20.5 ppm) dogs, in Mgi between GDV dogs with (590 +/- 34 ppm) and without (584 +/- 29 ppm) cardiac arrhythmias, and in Mgs between GDV dogs with (1.77 +/- 0.26 ppm) and without (1.51 +/- 0.09 ppm) cardiac arrhythmias. There was no correlation between Mgs and Mgi (R2 = 0.0001). Results indicate that Mg depletion is not pathophysiologically important in dogs with GDV and does not play a role in the cardiac arrhythmias detected in these patients.

  18. A Novel Approach to Neighborhood Fair Energy Trading in a Distribution Network of Multiple Microgrid Clusters

    DEFF Research Database (Denmark)

    Jadhav, Ashok Mohan; Patne, Nita Ravindra; Guerrero, Josep M.

    2018-01-01

    of their total surplus. To avoid the selfish behaviour of any buyer MG, an algorithm is used by the energy market operator which verifies the strategies submitted by buyer MGs before releasing set points to the generators. Apart from fairness and stability, the extensive numerical study confirms the ascendancy...... as a mediator between the trading parties. Depending on the priority factor, each buyer MG decides its strategy for energy demand from the surplus using a non-cooperative game theory based algorithm. The interests of seller MGs are protected by allowing them to decide the amount of energy they want to share out...

  19. Extraction of solubles from plant biomass for use as microbial growth stimulant and methods related thereto

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Ming Woei

    2015-12-08

    A method for producing a microbial growth stimulant (MGS) from a plant biomass is described. In one embodiment, an ammonium hydroxide solution is used to extract a solution of proteins and ammonia from the biomass. Some of the proteins and ammonia are separated from the extracted solution to provide the MGS solution. The removed ammonia can be recycled and the proteins are useful as animal feeds. In one embodiment, the method comprises extracting solubles from pretreated lignocellulosic biomass with a cellulase enzyme-producing growth medium (such T. reesei) in the presence of water and an aqueous extract.

  20. Methods and means of sodium fire fighting

    International Nuclear Information System (INIS)

    Zemskij, G.T.

    1985-01-01

    Methods and means for coaling sodium fire fighting are analyzed. Their advantages and drawbacks are considered. Comparative data on sodium fire fighting using some of considered compositions are presented. High efficiency of self-expanding compositions (Grafeks SK-23 and RS) is noted. Properties of MGS new composition for sodium fire fighting are considered. High fighting ability of the composition independent of burning metal layer width is shown. It is noted that fire fighting MGS efficiency decreases with growth of time of free fire burning which affects fire fighting methods. Technical means of powder delivery to burning sodium are reported

  1. Contributing to the Global Agenda

    DEFF Research Database (Denmark)

    Enemark, Stig

    2008-01-01

    Stig Enemark, President of the International Federation of Surveyors, explains the organisation's role in the areas of geospatial information and land management. Link to full text: http://www.euinfrastructure.com/currentissue/article.asp?art=273895&issue=259......Stig Enemark, President of the International Federation of Surveyors, explains the organisation's role in the areas of geospatial information and land management. Link to full text: http://www.euinfrastructure.com/currentissue/article.asp?art=273895&issue=259...

  2. Is Marcus Gunn jaw winking a primitive reflex? Rat neuroanatomy

    Directory of Open Access Journals (Sweden)

    Hou-Cheng Liang

    2018-03-01

    Full Text Available AIM: To investigate a possible trigeminal proprioceptive-oculomotor neural pathway and explore possible synaptic connections between neurons in this pathway. Attempt to bring a new insight to mechanism of Marcus Gunn syndrome (MGS. METHODS: Anterograde and retrograde tract tracing was applied and combined with immunofluorescent stain in rats. After electrophysiological identifying mesencephalic trigeminal nucleus (Vme neurons, intracellular injection of tracer was performed to trace axon trajectory. RESULTS: Following injections of anterograde tracers into the Vme, labeled terminals were observed ipsilateral in oculomotor and trochlear nuclei (III/IV, as well as in their premotor neurons in interstitial nucleus of Cajal and Darkschewitsch nucleus (INC/DN. Combining with choline acetyltransferase (ChAT immunofluorescent stain, it showed that Vme projecting terminals contact upon ChAT positive III/IV motoneurons under confocal microscope. By retrograde labeling premotor neurons of the III, it showed that Vme neuronal terminals contact with retrogradely labeled pre-oculomotor neurons in the INC/DN. Axons of intracellularly labeled Vme neurons that respond to electric stimuli of the masseter nerve traveled into the ipsilateral III. CONCLUSION: There may exist a trigeminal proprioceptive- oculomotor system neural circuit in the rat, which is probably related to vertical-torsional eye movements. Possible association of this pathway with MGS etiology was discussed.

  3. Desigualdades sociales en la mortalidad por cáncer de cuello de útero en la Ciudad Autónoma de Buenos Aires, 1999-2003 y 2004-2006

    Directory of Open Access Journals (Sweden)

    María Laura Martínez

    2013-01-01

    Full Text Available La literatura mundial describe diversos estudios sobre el manejo de trastornos mentales (TM en servicios no psiquiátricos; sin embargo, en el Perú los estudios están básicamente dirigidos a determinar la prevalencia de trastornos mentales en población general o en población hospitalaria no-psiquiátrica. Objetivo: Obtener información sobre las características y actitudes de los médicos generales (MGs y los patrones de manejo de pacientes con probables TM. Materiales y métodos: Se administró una encuesta a 73 médicos que trabajaban en servicios ambulatorios de medicina general en tres hospitales de Lima – Perú. Resultados: El 23% de los MGs recibieron algún curso de salud mental luego de haber concluido los estudios universitarios, 56% se siente confiado en su propia habilidad para diagnosticar un TM, 82% reporta interés en manejar médicamente a pacientes con TM y 66% de siente capaz de ayudarlos. Como práctica usual, 37% reporta realizar evaluación del estado mental (EEM, 48% dice preguntar sobre conducta sexual y 37% sobre historia personal y familiar de TM. La confianza en hacer un diagnóstico fue significativamente más elevada en MGs varones y en asistentes, pero el interés para manejarlos médicamente fue mayor en MGs mujeres. La actualización en salud mental en post-grado se asoció significativamente con la confianza en diagnosticar TM, preguntar sobre historia psiquiátrica y salud sexual, y realizar EEM. Los TM listados como más frecuentemente vistos fueron: depresión, trastornos somáticos sin explicación y trastornos de ansiedad. Los psicotrópicos listados como más utilizados fueron: hipnóticos/sedantes; tónicos, vitaminas y hierbas; y antidepresivos, particularmente tricíclicos. Diagnosticado un TM, 93% dice referirlo a un psiquiatra. Conclusiones: Factores relacionados a los MGs pueden influenciar los patrones de tratamiento de pacientes psiquiátricos en atención primaria.

  4. Manejo de pacientes con trastornos mentales en servicios ambulatorios de Medicina General en tres hospitales de Lima.

    Directory of Open Access Journals (Sweden)

    Robert De la Grecca Prevoo

    2005-10-01

    Full Text Available La literatura mundial describe diversos estudios sobre el manejo de trastornos mentales (TM en servicios no psiquiátricos; sin embargo, en el Perú los estudios están básicamente dirigidos a determinar la prevalencia de trastornos mentales en población general o en población hospitalaria no-psiquiátrica. Objetivo: Obtener información sobre las características y actitudes de los médicos generales (MGs y los patrones de manejo de pacientes con probables TM. Materiales y métodos: Se administró una encuesta a 73 médicos que trabajaban en servicios ambulatorios de medicina general en tres hospitales de Lima - Perú. Resultados: El 23% de los MGs recibieron algún curso de salud mental luego de haber concluido los estudios universitarios, 56% se siente confiado en su propia habilidad para diagnosticar un TM, 82% reporta interés en manejar médicamente a pacientes con TM y 66% de siente capaz de ayudarlos. Como práctica usual, 37% reporta realizar evaluación del estado mental (EEM, 48% dice preguntar sobre conducta sexual y 37% sobre historia personal y familiar de TM. La confianza en hacer un diagnóstico fue significativamente más elevada en MGs varones y en asistentes, pero el interés para manejarlos médicamente fue mayor en MGs mujeres. La actualización en salud mental en post-grado se asoció significativamente con la confianza en diagnosticar TM, preguntar sobre historia psiquiátrica y salud sexual, y realizar EEM. Los TM listados como más frecuentemente vistos fueron: depresión, trastornos somáticos sin explicación y trastornos de ansiedad. Los psicotrópicos listados como más utilizados fueron: hipnóticos/sedantes; tónicos, vitaminas y hierbas; y antidepresivos, particularmente tricíclicos. Diagnosticado un TM, 93% dice referirlo a un psiquiatra. Conclusiones: Factores relacionados a los MGs pueden influenciar los patrones de tratamiento de pacientes psiquiátricos en atención primaria. (Rev Med Hered 2005;16:246-252.

  5. "No former travellers having attained such a height on the Earth's surface": Instruments, inscriptions, and bodies in the Himalaya, 1800-1830.

    Science.gov (United States)

    Fleetwood, Lachlan

    2018-03-01

    East India Company surveyors began gaining access to the high Himalaya in the 1810s, at a time when the mountains were taking on increasing political significance as the northern borderlands of British India. Though never as idiosyncratic as surveyors insisted, these were spaces in which instruments, fieldbook inscriptions, and bodies were all highly prone to failure. The ways surveyors managed these failures (both rhetorically and in practice) demonstrate the social performances required to establish credible knowledge in a world in which the senses were scrambled. The resulting tensions reveal an ongoing disconnect in understanding between those displaced not only from London, but also from Calcutta, something insufficiently emphasized in previous histories of colonial science. By focusing on the early nineteenth century, often overlooked in favor of the later period, this article shows the extent to which the scientific, imaginative, and political constitution of the Himalaya was haphazard and contested.

  6. Defective replication initiation results in locus specific chromosome breakage and a ribosomal RNA deficiency in yeast.

    Directory of Open Access Journals (Sweden)

    Joseph C Sanchez

    2017-10-01

    Full Text Available A form of dwarfism known as Meier-Gorlin syndrome (MGS is caused by recessive mutations in one of six different genes (ORC1, ORC4, ORC6, CDC6, CDT1, and MCM5. These genes encode components of the pre-replication complex, which assembles at origins of replication prior to S phase. Also, variants in two additional replication initiation genes have joined the list of causative mutations for MGS (Geminin and CDC45. The identity of the causative MGS genetic variants strongly suggests that some aspect of replication is amiss in MGS patients; however, little evidence has been obtained regarding what aspect of chromosome replication is faulty. Since the site of one of the missense mutations in the human ORC4 alleles is conserved between humans and yeast, we sought to determine in what way this single amino acid change affects the process of chromosome replication, by introducing the comparable mutation into yeast (orc4Y232C. We find that yeast cells with the orc4Y232C allele have a prolonged S-phase, due to compromised replication initiation at the ribosomal DNA (rDNA locus located on chromosome XII. The inability to initiate replication at the rDNA locus results in chromosome breakage and a severely reduced rDNA copy number in the survivors, presumably helping to ensure complete replication of chromosome XII. Although reducing rDNA copy number may help ensure complete chromosome replication, orc4Y232C cells struggle to meet the high demand for ribosomal RNA synthesis. This finding provides additional evidence linking two essential cellular pathways-DNA replication and ribosome biogenesis.

  7. Defective replication initiation results in locus specific chromosome breakage and a ribosomal RNA deficiency in yeast.

    Science.gov (United States)

    Sanchez, Joseph C; Kwan, Elizabeth X; Pohl, Thomas J; Amemiya, Haley M; Raghuraman, M K; Brewer, Bonita J

    2017-10-01

    A form of dwarfism known as Meier-Gorlin syndrome (MGS) is caused by recessive mutations in one of six different genes (ORC1, ORC4, ORC6, CDC6, CDT1, and MCM5). These genes encode components of the pre-replication complex, which assembles at origins of replication prior to S phase. Also, variants in two additional replication initiation genes have joined the list of causative mutations for MGS (Geminin and CDC45). The identity of the causative MGS genetic variants strongly suggests that some aspect of replication is amiss in MGS patients; however, little evidence has been obtained regarding what aspect of chromosome replication is faulty. Since the site of one of the missense mutations in the human ORC4 alleles is conserved between humans and yeast, we sought to determine in what way this single amino acid change affects the process of chromosome replication, by introducing the comparable mutation into yeast (orc4Y232C). We find that yeast cells with the orc4Y232C allele have a prolonged S-phase, due to compromised replication initiation at the ribosomal DNA (rDNA) locus located on chromosome XII. The inability to initiate replication at the rDNA locus results in chromosome breakage and a severely reduced rDNA copy number in the survivors, presumably helping to ensure complete replication of chromosome XII. Although reducing rDNA copy number may help ensure complete chromosome replication, orc4Y232C cells struggle to meet the high demand for ribosomal RNA synthesis. This finding provides additional evidence linking two essential cellular pathways-DNA replication and ribosome biogenesis.

  8. Deficiency in origin licensing proteins impairs cilia formation: implications for the aetiology of Meier-Gorlin syndrome.

    Directory of Open Access Journals (Sweden)

    Tom Stiff

    Full Text Available Mutations in ORC1, ORC4, ORC6, CDT1, and CDC6, which encode proteins required for DNA replication origin licensing, cause Meier-Gorlin syndrome (MGS, a disorder conferring microcephaly, primordial dwarfism, underdeveloped ears, and skeletal abnormalities. Mutations in ATR, which also functions during replication, can cause Seckel syndrome, a clinically related disorder. These findings suggest that impaired DNA replication could underlie the developmental defects characteristic of these disorders. Here, we show that although origin licensing capacity is impaired in all patient cells with mutations in origin licensing component proteins, this does not correlate with the rate of progression through S phase. Thus, the replicative capacity in MGS patient cells does not correlate with clinical manifestation. However, ORC1-deficient cells from MGS patients and siRNA-mediated depletion of origin licensing proteins also have impaired centrosome and centriole copy number. As a novel and unexpected finding, we show that they also display a striking defect in the rate of formation of primary cilia. We demonstrate that this impacts sonic hedgehog signalling in ORC1-deficient primary fibroblasts. Additionally, reduced growth factor-dependent signaling via primary cilia affects the kinetics of cell cycle progression following cell cycle exit and re-entry, highlighting an unexpected mechanism whereby origin licensing components can influence cell cycle progression. Finally, using a cell-based model, we show that defects in cilia function impair chondroinduction. Our findings raise the possibility that a reduced efficiency in forming cilia could contribute to the clinical features of MGS, particularly the bone development abnormalities, and could provide a new dimension for considering developmental impacts of licensing deficiency.

  9. A Privacy-Preserving Distributed Optimal Scheduling for Interconnected Microgrids

    Directory of Open Access Journals (Sweden)

    Nian Liu

    2016-12-01

    Full Text Available With the development of microgrids (MGs, interconnected operation of multiple MGs is becoming a promising strategy for the smart grid. In this paper, a privacy-preserving distributed optimal scheduling method is proposed for the interconnected microgrids (IMG with a battery energy storage system (BESS and renewable energy resources (RESs. The optimal scheduling problem is modeled to minimize the coalitional operation cost of the IMG, including the fuel cost of conventional distributed generators and the life loss cost of BESSs. By using the framework of the alternating direction method of multipliers (ADMM, a distributed optimal scheduling model and an iteration solution algorithm for the IMG is introduced; only the expected exchanging power (EEP of each MG is required during the iterations. Furthermore, a privacy-preserving strategy for the sharing of the EEP among MGs is designed to work with the mechanism of the distributed algorithm. According to the security analysis, the EEP can be delivered in a cooperative and privacy-preserving way. A case study and numerical results are given in terms of the convergence of the algorithm, the comparison of the costs and the implementation efficiency.

  10. SVC control enhancement applying self-learning fuzzy algorithm for islanded microgrid

    Directory of Open Access Journals (Sweden)

    Hossam Gabbar

    2016-03-01

    Full Text Available Maintaining voltage stability, within acceptable levels, for islanded Microgrids (MGs is a challenge due to limited exchange power between generation and loads. This paper proposes an algorithm to enhance the dynamic performance of islanded MGs in presence of load disturbance using Static VAR Compensator (SVC with Fuzzy Model Reference Learning Controller (FMRLC. The proposed algorithm compensates MG nonlinearity via fuzzy membership functions and inference mechanism imbedded in both controller and inverse model. Hence, MG keeps the desired performance as required at any operating condition. Furthermore, the self-learning capability of the proposed control algorithm compensates for grid parameter’s variation even with inadequate information about load dynamics. A reference model was designed to reject bus voltage disturbance with achievable performance by the proposed fuzzy controller. Three simulations scenarios have been presented to investigate effectiveness of proposed control algorithm in improving steady-state and transient performance of islanded MGs. The first scenario conducted without SVC, second conducted with SVC using PID controller and third conducted using FMRLC algorithm. A comparison for results shows ability of proposed control algorithm to enhance disturbance rejection due to learning process.

  11. Power Electronics for Microgrids

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Blaabjerg, Frede

    2016-01-01

    A microgrid (MG) is a stand-alone or grid-connected hybrid renewable system that uses distributed renewable and nonrenewable energy sources and energy storage systems (ESSs) to supply power to local loads. The system is ordinarily based on power electronics, with interface converters allowing...... a continuous supply of power in the presence of variable RES production. This chapter describes some specific features of DC MGs in terms of power architecture, control, and protection. It also reviews several uncommon power electronic interfaces. Regarding control, operation without critical communication...... are explained in this chapter. The chapter concludes with a review of power electronic intensive protection solutions for DC MGs....

  12. Detecting Structural Features in Metallic Glass via Synchrotron Radiation Experiments Combined with Simulations

    Directory of Open Access Journals (Sweden)

    Gu-Qing Guo

    2015-11-01

    Full Text Available Revealing the essential structural features of metallic glasses (MGs will enhance the understanding of glass-forming mechanisms. In this work, a feasible scheme is provided where we performed the state-of-the-art synchrotron-radiation based experiments combined with simulations to investigate the microstructures of ZrCu amorphous compositions. It is revealed that in order to stabilize the amorphous state and optimize the topological and chemical distribution, besides the icosahedral or icosahedral-like clusters, other types of clusters also participate in the formation of the microstructure in MGs. This cluster-level co-existing feature may be popular in this class of glassy materials.

  13. Penerapan Metode K-nearest Neighbor pada Penentuan Grade Dealer Sepeda Motor

    OpenAIRE

    Leidiyana, Henny

    2017-01-01

    The mutually beneficial cooperation is a very important thing for a leasing and dealer. Incentives for marketing is given in order to get consumers as much as possible. But sometimes the surveyor objectivity is lost due to the conspiracy on the field of marketing and surveyors. To overcome this, leasing a variety of ways one of them is doing ranking against the dealer. In this study the application of the k-Nearest Neighbor method and Euclidean distance measurement to determine the grade deal...

  14. Magnesium sulphate and the development of the common bean cultivated in an Ultisol of Northeast Australia Sulfato de magnésio e o desenvolvimento do feijoeiro comum cultivado em um Ultissolo do Nordeste da Australia

    Directory of Open Access Journals (Sweden)

    Itamar Pereira de Oliveira

    2000-03-01

    Full Text Available Magnesium applications (MgS0(4.7H(20 to achieve 8 and 16 mmol c/cm3 of Mg (324 and 1284 kg of MgS0(4 ha-1 were made on one Ultisol from Australia Northeast to correct Mg deficiency in plants and to verify the optimum level of Mg to grow common bean (Phaseolus vulgaris L. Magnesium was applied together with lime, N, K, Cu, Zn, B, and Mo as calcium carbonate, ammonium nitrate, potassium phosphate, cupric and zinc sulphate, boric acid and sodium molybdate respectively a month before planting and P as phosphoric acid at the planting. The pH reached the equilibrium after six weeks of incubation. Higher electrical conductivity (EC was observed in soil where Mg was applied to reach 8 mmol c/cm3 in the absence of common bean and 16 mmol c/cm3 when the plant was present. Higher plant height, leaf area, dry matter weight:leaf area ratio and nutrient concentrations were observed in plants cultivated in soils treated with Mg to reach 8 mmol c/cm3 and 16 mmol c/cm3 when the plant was present. The plant top P content was very low but N, Ca and Mg contents can be considered normal for the common bean.Aplicações de sulfato de magnésio (MgS0(4.7H(20 para atigir 8 e 16 mmol c/cm3 de Mg (324 e 1284 kg de MgS0(4 ha-1 foram realizadas em um solo Ultissolo com a finalidade de corrigir deficiências de Mg no feijoeiro e verificar o nível de Mg suficiente para cultivar o feijão comum (Phaseolus vugaris L. O magnésio foi aplicado junto com calcário, N, K, Cu, Zn, B e Mo, como carbonato de cálcio, nitrato de amônio, fosfato de potássio, sulfato de cobre, sulfato de zinco, ácido bórico e molibidato de sódio respectivamente, um mês antes do plantio e o P como ácido fosfórico no plantio. O pH alcançou o equilíbrio após seis semanas de incubação. A condutividade elétrica mais alta (CE foi observada em solo onde o Mg foi aplicado para atingir 8 mmol c/cm3 na ausência e 16 mmol c/cm3 na presença do feijoeiro A altura das plantas , área foliar, rela

  15. VGI in surveying engineering: Introducing collaborative cloud land surveying

    Directory of Open Access Journals (Sweden)

    Ioannis Sofos

    2017-12-01

    Full Text Available Volunteered geographic information (VGI has enabled many innovative applications in various scientific fields. This paper introduces a new framework called "collaborative cloud-based land surveying" (CCLS that uses VGI principles for data sharing among surveyor engineers to boost the productivity and improve the quality of their applications. A cloud-based spatio-temporal data repository is presented, aiming to facilitate the sharing of VGI among surveyor engineers. A fully-functional distributed software application has been developed and used to apply CCLS in a large-scale land surveying project run by the Greek Ministry of Culture, which involves the mapping of the historic center of Athens. Results from the data analysis of hundreds of measurements indicate a substantial (30% to 60% error reduction and also a significant productivity raise (~22%. The collected measurements are shared in an online database, accessible by professional surveyors who can in turn contribute their own data to further enhance the CCLS system.

  16. Mobile Interfaces for Building Control Surveyors

    OpenAIRE

    Chmielewski , Jacek; Walczak , Krzysztof; Wiza , Wojciech

    2010-01-01

    International audience; The problem of integrating heterogeneous back-end platforms used in public administration has been widely addressed in a number of research and development projects. In such a complex and heterogeneous environment, application of the SOA paradigm can be particularly beneficial. However, in some application domains - such as the Building Control Administration - there is an additional requirement: integration of heterogeneous front-end platforms - including access throu...

  17. Testing the cosmological constant as a candidate for dark energy

    International Nuclear Information System (INIS)

    Kratochvil, Jan; Linde, Andrei; Linder, Eric V.; Shmakova, Marina

    2004-01-01

    It may be difficult to single out the best model of dark energy on the basis of the existing and planned cosmological observations, because many different models can lead to similar observational consequences. However, each particular model can be studied and either found consistent with observations or ruled out. In this paper, we concentrate on the possibility to test and rule out the simplest and by far the most popular of the models of dark energy, the theory described by general relativity with positive vacuum energy (the cosmological constant). We evaluate the conditions under which this model could be ruled out by the future observations made by the Supernova/Acceleration Probe SNAP (both for supernovae and weak lensing) and by the Planck Surveyor cosmic microwave background satellite

  18. Multifunctional microstructured polymer films for boosting solar power generation of silicon-based photovoltaic modules.

    Science.gov (United States)

    Leem, Jung Woo; Choi, Minkyu; Yu, Jae Su

    2015-02-04

    We propose two-dimensional periodic conical micrograting structured (MGS) polymer films as a multifunctional layer (i.e., light harvesting and self-cleaning) at the surface of outer polyethylene terephthalate (PET) cover-substrates for boosting the solar power generation in silicon (Si)-based photovoltaic (PV) modules. The surface of ultraviolet-curable NOA63 MGS polymer films fabricated by the soft imprint lithography exhibits a hydrophobic property with water contact angle of ∼121° at no inclination and dynamic advancing/receding water contact angles of ∼132°/111° at the inclination angle of 40°, respectively, which can remove dust particles or contaminants on the surface of PV modules in real outdoor environments (i.e., self-cleaning). The NOA63 MGS film coated on the bare PET leads to the reduction of reflection as well as the enhancement of both the total and diffuse transmissions at wavelengths of 300-1100 nm, indicating lower solar weighted reflectance (RSW) of ∼8.2%, higher solar weighted transmittance (TSW) of ∼93.1%, and considerably improved average haze ratio (HAvg) of ∼88.3% as compared to the bare PET (i.e., RSW ≈ 13.5%, TSW ≈ 86.9%, and HAvg ≈ 9.1%), respectively. Additionally, it shows a relatively good durability at temperatures of ≤160 °C. The resulting Si PV module with the NOA63 MGS/PET has an enhanced power conversion efficiency (PCE) of 13.26% (cf., PCE = 12.55% for the reference PV module with the bare PET) due to the mainly improved short circuit current from 49.35 to 52.01 mA, exhibiting the PCE increment percentage of ∼5.7%. For light incident angle-dependent PV module current-voltage characteristics, superior solar energy conversion properties are also obtained in a broad angle range of 10-80°.

  19. Variação na qualidade do azeite em cultivares de oliveira

    Directory of Open Access Journals (Sweden)

    Luiz Fernando de Oliveira da Silva

    2012-01-01

    Full Text Available O cultivo de oliveira (Olea europaea L. no sul de Minas Gerais tem apresentado resultados promissores quanto à produção de frutos. No entanto, há necessidade de verificar seu valor nutritivo e a qualidade do azeite oriundo dos frutos das cultivares potencialmente produtivas. Objetivou-se com este trabalho determinar a composição centesimal dos frutos, as características químicas e o perfil de ácidos graxos dos azeites extraídos de diferentes cultivares de oliveira, com a finalidade de selecionar os materiais com potencial agroindustrial. Foram avaliadas 32 cultivares de oliveira com seis anos de idades quanto à composição centesimal (teores de umidade, lipídeos, proteínas e cinzas, tanto na polpa quanto no caroço dos frutos; composição química e perfil de ácidos graxos dos azeites. Observaram-se nas cultivares MGS ASC315, Cerignola, MGS GRAP561 e MGS GRAP575 maiores valores de lipídeos. Além disso, as análises indicaram que o caroço possui quantidades significativas de lipídeos, embora sempre inferiores às quantidades presentes na polpa. Os índices de acidez em ácido oleico, peróxidos e refração absoluta estão de acordo com a resolução da ANVISA, podendo ser inicialmente classificados como azeite de oliva extravirgem ou virgem. De modo geral, todos os ácidos graxos presentes nos azeites possuem valores satisfatórios, destacando a cultivar MGS GRAP084, com maior concentração de ácido oleico, principal ácido responsável pelos benefícios à saúde.

  20. Introduction: Chapter 1

    Science.gov (United States)

    Esque, Todd C.; Nussear, Kenneth E.; Inman, Richard D.; Matocq, Marjorie D.; Weisberg, Peter J.; Dilts, Thomas E.; Leitner, Philip

    2013-01-01

    The Mohave ground squirrel (Xerospermophilus mohavensis), named just over a century ago (Merriam 1889), is precinctive to the western Mojave Desert in California, USA, and occupies portions of Kern, Los Angeles, Inyo and San Bernardino counties (Best 1995). Early estimates of the geographic range of the squirrel are just 20,000 km2 in area (Hall 1981, Zeiner et al. 1988‐ 1990), one of the smallest distributions among North American ground squirrel species (Hoyt 1972, P. Leitner – pers. obs.). The closest living relative of the Mohave ground squirrel (MGS) is the round‐tailed ground squirrel (Xerospermophilus tereticaudus). Mohave ground squirrels have a “shorter tail with distichous hairs and white undersurface”, but visual differences between the two species are subtle (Hafner and Yates 1983). Speciation likely occurred when portions of the parent population were isolated 4‐1.6 million years ago during the accelerated uplift of the Sierra Nevada, the Transverse Ranges and the Mojave River system, resulting in separation and isolation with MGS evolving in refugia (Hafner 1992, Bell et al. 2009). Subsequently, fluvial‐ lacustrine systems in the Mojave River basin provided vicariance features during the Pleistocene (Hafner 1992, Bell et al. 2009). Responding to previous climate change, the two species potentially migrated into their current ranges from southern refugia after the Last Glacial Maximum, eventually abutting each other along the Mojave River (Hafner and Yates 1983). The species are capable of hybridizing, but intercrosses appear to be rare, and sampling near the zones of potential hybridization remains limited (Bell and Matocq 2011). The only other similar sized squirrel occupying the range of MGS is the white‐tailed antelope ground squirrel (Ammospermophilus leucurus) whose range entirely overlaps MGS, but is easily distinguished by its bright white dorso‐lateral stripes (Best 1995)

  1. Towards self-sustainable power systems

    DEFF Research Database (Denmark)

    Angjelichinoski, Marko; Danzi, Pietro; Stefanovic, Cedomir

    2017-01-01

    We propose use of a “modemless” communication solution, termed power talk, tailored for optimization and monitoring, i.e., upper layer control in low voltage DC MicroGrids (MGs). Specifically, the exchange of the information required for the upper control among control agents is achieved by modul......We propose use of a “modemless” communication solution, termed power talk, tailored for optimization and monitoring, i.e., upper layer control in low voltage DC MicroGrids (MGs). Specifically, the exchange of the information required for the upper control among control agents is achieved...... of minimizing the cost of the generation. The simulation results prove the feasibility of power talk as enabler of fully self-sustainable DC MicroGrids....

  2. Osmium isotope and highly siderophile element systematics of the lunar crust

    Science.gov (United States)

    Day, J.M.D.; Walker, R.J.; James, O.B.; Puchtel, I.S.

    2010-01-01

    Coupled 187Os/188Os and highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance data are reported for pristine lunar crustal rocks 60025, 62255, 65315 (ferroan anorthosites, FAN) and 76535, 78235, 77215 and a norite clast in 15455 (magnesian-suite rocks, MGS). Osmium isotopes permit more refined discrimination than previously possible of samples that have been contaminated by meteoritic additions and the new results show that some rocks, previously identified as pristine, contain meteorite-derived HSE. Low HSE abundances in FAN and MGS rocks are consistent with derivation from a strongly HSE-depleted lunar mantle. At the time of formation, the lunar floatation crust, represented by FAN, had 1.4 ?? 0.3 pg g- 1 Os, 1.5 ?? 0.6 pg g- 1 Ir, 6.8 ?? 2.7 pg g- 1 Ru, 16 ?? 15 pg g- 1 Pt, 33 ?? 30 pg g- 1 Pd and 0.29 ?? 0.10 pg g- 1 Re (??? 0.00002 ?? CI) and Re/Os ratios that were modestly elevated (187Re/188Os = 0.6 to 1.7) relative to CI chondrites. MGS samples are, on average, characterised by more elevated HSE abundances (??? 0.00007 ?? CI) compared with FAN. This either reflects contrasting mantle-source HSE characteristics of FAN and MGS rocks, or different mantle-crust HSE fractionation behaviour during production of these lithologies. Previous studies of lunar impact-melt rocks have identified possible elevated Ru and Pd in lunar crustal target rocks. The new results provide no supporting evidence for such enrichments. If maximum estimates for HSE in the lunar mantle are compared with FAN and MGS averages, crust-mantle concentration ratios (D-values) must be ??? 0.3. Such D-values are broadly similar to those estimated for partitioning between the terrestrial crust and upper mantle, with the notable exception of Re. Given the presumably completely different mode of origin for the primary lunar floatation crust and tertiary terrestrial continental crust, the potential similarities in crust-mantle HSE partitioning for the Earth and Moon are somewhat

  3. A success by any measure

    CERN Multimedia

    2004-01-01

    Thanks to CERN's team of surveyors, the Organization's stand at the Night of Science attracted a large number of visitors. The technology and tools used by the surveyors, such as the Terrameter shown here, attracted many visitors to the CERN stand. Almost 500 visitors to the fifth annual Night of Science on 3 and 4 July had their height photogrametrically measured to an accuracy of one thousandth of a millimetre and came away with a certificate displaying the result. The theme of this year's Night of Science event was 'measuring and counting', which brought CERN's surveyors into the spotlight with an attractive and entertaining exhibition of all the various tools and the latest cutting-edge technology they use in their work. Over the two days, around 400 scientists, actors and artists at 90 different stands spread across the park of the Perle du Lac entertained the general public on the theme of measurement. The broad nature of the theme meant that many different scientific disciplines had the opportunity t...

  4. A Survey on Smart Agent-Based Microgrids for Resilient/Self-Healing Grids

    Directory of Open Access Journals (Sweden)

    Kaveh Dehghanpour

    2017-05-01

    Full Text Available This paper presents an overview of our body of work on the application of smart control techniques for the control and management of microgrids (MGs. The main focus here is on the application of distributed multi-agent system (MAS theory in multi-objective (MO power management of MGs to find the Pareto-front of the MO power management problem. In addition, the paper presents the application of Nash bargaining solution (NBS and the MAS theory to directly obtain the NBS on the Pareto-front. The paper also discusses the progress reported on the above issues from the literature. We also present a MG-based power system architecture for enhancing the resilience and self-healing of the system.

  5. A GPS-Based Decentralized Control Method for Islanded Microgrids

    DEFF Research Database (Denmark)

    Golsorkhi, Mohammad; Lu, Dylan; Guerrero, Josep M.

    2017-01-01

    Coordinated control of distributed energy resources (DER) is essential for the operation of islanded microgrids (MGs). Conventionally, such coordination is achieved by drooping the frequency of the reference voltage versus active (or reactive) power. The conventional droop method ensures synchron......Coordinated control of distributed energy resources (DER) is essential for the operation of islanded microgrids (MGs). Conventionally, such coordination is achieved by drooping the frequency of the reference voltage versus active (or reactive) power. The conventional droop method ensures......, GPS timing technology is utilized to synchronize the DERs to a common reference frame, rotating at nominal frequency. In addition, an adaptive Q-f droop controller is introduced as a backup to ensure stable operation during GPS signal interruptions. In the context of the common reference frame, even...

  6. Propagation of stationary Rossby waves in the Martian lower atmosphere

    Science.gov (United States)

    Ghosh, Priyanka; Thokuluwa, Ramkumar

    The Martian lower atmospheric (-1.5 km to 29.3 km) temperature, measured by radio occultation technique during the Mars Global Surveyor (MGS) mission launched by US in November 1996, at the Northern winter hemispheric latitude of about 63(°) N clearly shows a statistically significant (above 95 percent confidential level white noise) and strong 3.5-day oscillation during 1-10 January 2006. This strong signal occurs in the longitudinal sectors of 0-30(°) E and 190-230(°) E but statistically insignificant in almost all the other longitudes. This 180 degree separation between the two peaks of occurrence of strong 3.5 day oscillation indicates that this may be associated with zonal wave number 2 structure global scale wave. At the lowest height of -1.5 km, the power observed in the longitude of 0-30(°) E is 50 K (2) and it increased gradually to the maximum power of 130 K (2) at the height of 0.8 - 1.7 km. Above this height, the power decreased monotonously and gradually to insignificant level at the height of 3.7 km (20 K (2) ). This gradual decrease of power above the height of 1.7 km indicates that radiative damping (infra red cooling due to large abundance of CO _{2} molecules and dust particles) would have played an important role in the dissipation of waves. The height and longitudinal profiles of phase of the 3.5-day wave indicate that this wave is a vertically standing and eastward propagating planetary wave respectively. Since the statistically significant spectral amplitude occurs near the high topography structures, it seems that the wave is generated by flows over the topography. In the Northern winter, it is possible that the large gradient of temperature between the low and high latitudes would lead to flow of winds from the tropical to polar latitudes. Due to the Coriolis effect, this flow would in turn move towards the right and incite wave generation when the air flows over the high topographic structures. This lead to speculate that the observed 3

  7. Using clinical indicators to facilitate quality improvement via the accreditation process: an adaptive study into the control relationship.

    Science.gov (United States)

    Chuang, Sheuwen; Howley, Peter P; Hancock, Stephen

    2013-07-01

    The aim of the study was to determine accreditation surveyors' and hospitals' use and perceived usefulness of clinical indicator reports and the potential to establish the control relationship between the accreditation and reporting systems. The control relationship refers to instructional directives, arising from appropriately designed methods and efforts towards using clinical indicators, which provide a directed moderating, balancing and best outcome for the connected systems. Web-based questionnaire survey. Australian Council on Healthcare Standards' (ACHS) accreditation and clinical indicator programmes. Seventy-three of 306 surveyors responded. Half used the reports always/most of the time. Five key messages were revealed: (i) report use was related to availability before on-site investigation; (ii) report use was associated with the use of non-ACHS reports; (iii) a clinical indicator set's perceived usefulness was associated with its reporting volume across hospitals; (iv) simpler measures and visual summaries in reports were rated the most useful; (v) reports were deemed to be suitable for the quality and safety objectives of the key groups of interested parties (hospitals' senior executive and management officers, clinicians, quality managers and surveyors). Implementing the control relationship between the reporting and accreditation systems is a promising expectation. Redesigning processes to ensure reports are available in pre-survey packages and refined education of surveyors and hospitals on how to better utilize the reports will support the relationship. Additional studies on the systems' theory-based model of the accreditation and reporting system are warranted to establish the control relationship, building integrated system-wide relationships with sustainable and improved outcomes.

  8. An automated locating and data logging system for geophysical surveys

    International Nuclear Information System (INIS)

    Nyquist, J.E.; Blair, M.S.

    1990-01-01

    Oak Ridge National Laboratory has developed an Ultrasonic Ranging and Data System (USRADS) and interfaced the system with a Geonics EM31 terrain conductivity meter. USRADS keeps track of a surveyor's position by measuring the time-of-flight of ultrasonic pulses from an transducer carried by the surveyor in a backpack to stationary receivers arrayed over the survey area. Also built into the backpack is a radio transmitter that sends the EM31 data to a base station (van or truck) where the surveyor's position and the EM31 quadrature and inphase data are automatically recorded once a second on a portable computer. We surveyed a 13-acre landfill at Idaho National Engineering Laboratory with three people, in three days, collecting over 25,000 EM31 quadrature and inphase readings. At a normal walking pace the average distance between measurement points along the surveyor's path was about 2 ft, with an overall positioning precision of about 0.5 ft for each point. USRADS offers several advantages over conventional EM31 surveys: (1) time and money are saved because it does not require a civil survey to lay a grid before the geophysical survey begins, (2) data are directly recorded by a portable computer and are available for analysis in the field, and (3) refining or expanding the grid about an anomaly does not require civil surveying to add extra grid points. USRADS can also be used with a gamma scintillometer for radiation surveys. Currently, we are working to interface USRADS with a portable X-ray fluorescence spectrometer for detecting heavy metals in soil

  9. NASA's Human Mission to a Near-Earth Asteroid: Landing on a Moving Target

    Science.gov (United States)

    Smith, Jeffrey H.; Lincoln, William P.; Weisbin, Charles R.

    2011-01-01

    This paper describes a Bayesian approach for comparing the productivity and cost-risk tradeoffs of sending versus not sending one or more robotic surveyor missions prior to a human mission to land on an asteroid. The expected value of sample information based on productivity combined with parametric variations in the prior probability an asteroid might be found suitable for landing were used to assess the optimal number of spacecraft and asteroids to survey. The analysis supports the value of surveyor missions to asteroids and indicates one launch with two spacecraft going simultaneously to two independent asteroids appears optimal.

  10. SAJAA SepOct 33-38

    African Journals Online (AJOL)

    Studio G5

    Background: Higher dermatomal block following spinal anaesthesia impairs ... Group B received intrathecal anaesthesia 15 mgs of bupivacaine with 0.5 ml of normal saline ..... patient's ability to cough effectively, despite sensory segmental.

  11. Organic Seston Dynamics in Upland Neotropical Streams: Implications for Amphibian Declines

    Science.gov (United States)

    Peterson, S. D.; Colon-Gaud, C.; Whiles, M. R.; Hunte-Brown, M.; Connelly, S.; Kilham, S.; Pringle, C. M.; Lips, K. R.; Brenes, R.

    2005-05-01

    Organic seston represents food for filter feeders and a mechanism for downstream transport of energy and nutrients. As part of a study assessing the ecological impacts of stream-breeding anuran extirpations, we examined seston dynamics in 2 stream reaches with tadpoles (El Cope) and 2 without (Fortuna) in the Panamanian uplands. All reaches are high gradient with annual average discharge ranging from 46-102 L/s. Samples were collected multiple times per month at various discharges, sieved into fine (98μm) and very fine (1.6μm) fractions, and processed to estimate ash-free dry mass (AFDM), total C, and total N. Average annual concentrations ranged from 0.52- 2.51 mg/L (fine) and 2.04-3.14 mg/L (very fine), and total export ranged from 0.27-7,981 mg/s across all streams. On average, very fine particles comprised 78% of export from El Cope sites and 61% from Fortuna streams. Average total N export ranged from 5.32-30.53 mg/s in El Cope sites and 1.71-6.04 mg/s at Fortuna. Average particle quality (C/N) in El Cope streams was higher (7.6) than Fortuna streams (11.5). Lower export of very fine particles and lower seston quality in Fortuna streams suggests the loss of tadpoles may influence seston dynamics and quality in these systems.

  12. A Signature of Inflation from Dynamical Supersymmetry Breaking

    CERN Document Server

    Kinney, W H; Kinney, William H.; Riotto, Antonio

    1998-01-01

    In models of cosmological inflation motivated by dynamical supersymmetry breaking, the potential driving inflation may be characterized by inverse powers of a scalar field. These models produce observables similar to those typical of the hybrid inflation scenario: negligible production of tensor (gravitational wave) modes, and a blue scalar spectral index. In this short note, we show that, unlike standard hybrid inflation models, dynamical supersymmetric inflation (DSI) predicts a measurable deviation from a power-law spectrum of fluctuations, with a variation in the scalar spectral index $|dn / d(\\ln k)|$ may be as large as 0.05. DSI can be observationally distinguished from other hybrid models with cosmic microwave background measurements of the planned sensitivity of the ESA's Planck Surveyor.

  13. Observing participating observation

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    2011-01-01

    Current methodology concerning participating observation in general leaves the act of observation unobserved. Approaching participating observation from systems theory offers fundamental new insights into the topic. Observation is always participation. There is no way to escape becoming...

  14. Observing participating observation

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    2010-01-01

    Current methodology concerning participating observation in general leaves the act of observation unobserved. Approaching participating observation from systems theory offers fundamental new insights into the topic. Observation is always participation. There is no way to escape becoming...

  15. Solar and Interplanetary Disturbances causing Moderate ...

    Indian Academy of Sciences (India)

    magnetospheric conditions leading to 121 moderate geomagnetic storms. (MGS) have been ... increases on sudden storm commencement (SSC) day than its previous day value and acquires .... Tokyo, Japan. Webb, D. F. 1995, Rev. Geophys.

  16. Meckel Gruber Syndrome: Correlation Between Prenatal Diagnosis and Autopsy Findings

    Directory of Open Access Journals (Sweden)

    Hülya Akgün

    2008-04-01

    CONCLUSION: Ultrasonographic findings of MGS allow for diagnosis of the most cases. However autopsy may be valuable for confirmation of the diagnosis and to evaluate the recurrence risk in future pregnancies.

  17. Moon/Mars Landing Commemorative Release: Gusev Crater and Ma'adim Vallis

    Science.gov (United States)

    1998-01-01

    On July 20, 1969, the first human beings landed on the Moon. On July 20, 1976, the first robotic lander touched down on Mars. This July 20th-- 29 years after Apollo 11 and 22 years since the Viking 1 Mars landing-- we take a look forward toward one possible future exploration site on the red planet.One of the advantages of the Mars Global Surveyor Mars Orbiter Camera (MOC) over its predecessors on the Viking and Mariner spacecraft is resolution. The ability to see-- resolve--fine details on the martian surface is key to planning future landing sites for robotic and, perhaps, human explorers that may one day visit the planet.At present, NASA is studying potential landing sites for the Mars Surveyor landers, rovers, and sample return vehicles that are scheduled to be launched in 2001, 2003, and 2005. Among the types of sites being considered for these early 21st Century landings are those with 'exobiologic potential'--that is, locations on Mars that are in some way related to the past presence of water.For more than a decade, two of the prime candidates suggested by various Mars research scientists are Gusev Crater and Ma'adim Vallis. Located in the martian southern cratered highlands at 14.7o S, 184.5o W, Gusev Crater is a large, ancient, meteor impact basin that--after it formed--was breached by Ma'adim Vallis.Viking Orbiter observations provided some evidence to suggest that a fluid--most likely, water--once flowed through Ma'adim Vallis and into Gusev Crater. Some scientists have suggested that there were many episodes of flow into Gusev Crater (as well as flow out of Gusev through its topographically-lower northwestern rim). Some have also indicated that there were times when Ma'adim Vallis, also, was full of water such that it formed a long, narrow lake.The possibility that water flowed into Gusev Crater and formed a lake has led to the suggestion that the materials seen on the floor of this crater--smooth-surfaced deposits, buried craters, and huge mesas near

  18. Robust Networked Control Scheme for Distributed Secondary Control of Islanded MicroGrids

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Stefanovic, Cedomir; Dragicevic, Tomislav

    2014-01-01

    Distributed secondary control (DSC) is a new approach for microgrids (MGs) by which the frequency, voltage and power can be regulated by using only local unit controllers. Such a solution is necessary for anticipated scenarios that have an increased number of distributed generators (DGs) within...... the MG. Due to the constrained traffic pattern required by the secondary control, it is viable to implement a dedicated local area communication functionality among the local controllers. This paper presents a new, wireless-based robust communication algorithm for the DSC of MGs. The algorithm tightly...... couples the communication and the control functionality, such that the transmission errors are absorbed through an averaging operation performed in each local controller, resulting in a very high reliability. Furthermore, transmissions from each DG are periodic and prescheduled broadcasts, and in this way...

  19. Model Predictive Control of Power Converters for Robust and Fast Operation of AC Microgrids

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav

    2018-01-01

    the load power at the same time. Those functionalities are conventionally achieved by hierarchical linear control loops. However, they have limited transient response and high sensitivity to parameter variations. This paper aims to mitigate these problems by firstly introducing an improvement of the FCS......This paper proposes the application of a finite control set model predictive control (FCS-MPC) strategy in standalone ac microgrids (MGs). AC MGs are usually built from two or more voltage source converters (VSCs) which can regulate the voltage at the point of common coupling, while sharing......-MPC strategy for a single VSC based on tracking of derivative of the voltage reference trajectory. Using only a single step prediction horizon, the proposed strategy exhibits low computational expense but provides steady state performance comparable to PWM, while its transient response and robustness...

  20. Locating the rate-limiting step for the interaction of hydrogen with Mg(0001) using density-functional theory calculations and rate theory

    DEFF Research Database (Denmark)

    Vegge, Tejs

    2004-01-01

    The dissociation of molecular hydrogen on a Mgs0001d surface and the subsequent diffusion of atomic hydrogen into the magnesium substrate is investigated using Density Functional Theory (DFT) calculations and rate theory. The minimum energy path and corresponding transition states are located usi...... to be rate-limiting for the ab- and desorption of hydrogen, respectively. Zero-point energy contributions are found to be substantial for the diffusion of atomic hydrogen, but classical rates are still found to be within an order of magnitude at room temperature.......The dissociation of molecular hydrogen on a Mgs0001d surface and the subsequent diffusion of atomic hydrogen into the magnesium substrate is investigated using Density Functional Theory (DFT) calculations and rate theory. The minimum energy path and corresponding transition states are located using...

  1. MAS-based Distributed Coordinated Control and Optimization in Microgrid and Microgrid Clusters: A Comprehensive Overview

    DEFF Research Database (Denmark)

    Han, Yang; Zhang, Ke; Hong, Li

    2018-01-01

    The increasing integration of the distributed renewable energy sources highlights the requirement to design various control strategies for microgrids (MGs) and microgrid clusters (MGCs). The multi-agent system (MAS)-based distributed coordinated control strategies shows the benefits to balance...... the power and energy, stabilize voltage and frequency, achieve economic and coordinated operation among the MGs and MGCs. However, the complex and diverse combinations of distributed generations in multi-agent system increase the complexity of system control and operation. In order to design the optimized...... configuration and control strategy using MAS, the topology models and mathematic models such as the graph topology model, non-cooperative game model, the genetic algorithm and particle swarm optimization algorithm are summarized. The merits and drawbacks of these control methods are compared. Moreover, since...

  2. A Tale of 3 Craters

    Science.gov (United States)

    2004-01-01

    11 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image captures some of the complexity of the martian upper crust. Mars does not simply have an impact-cratered surface, it's upper crust is a cratered volume. Over time, older craters on Mars have been eroded, filled, buried, and in some cases exhumed and re-exposed at the martian surface. The crust of Mars is layered to depths of 10 or more kilometers, and mixed in with the layered bedrock are a variety of ancient craters with diameters ranging from a few tens of meters (a few tens of yards) to several hundred kilometers (more than one or two hundred miles). The picture shown here captures some of the essence of the layered, cratered volume of the upper crust of Mars in a very simple form. The image shows three distinct circular features. The smallest, in the lower right quarter of the image, is a meteor crater surrounded by a mound of material. This small crater formed within a layer of bedrock that once covered the entire scene, but today is found only in this small remnant adjacent to the crater. The intermediate-sized crater, west (left) of the small one, formed either in the next layer down--that is, below the layer in which the small crater formed--or it formed in some layers that are now removed, but was big enough to penetrate deeply into the rock that is near the surface today. The largest circular feature in the image, in the upper right quarter of the image, is still largely buried. It formed in layers of rock that are below the present surface. Erosion has brought traces of its rim back to the surface of Mars. This picture is located near 50.0oS, 77.8oW, and covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates this October 2004 image from the upper left.

  3. Meier-Gorlin syndrome Clinical genetics and genomics

    NARCIS (Netherlands)

    S. de Munnik (Sonja); E.H. Hoefsloot (Lies); J. Roukema (Jolt); J. Schoots (Jeroen); N.V.A.M. Knoers (Nine); H.G. Brunner; A.P. Jackson (Andrew); E. Bongers (Ernie)

    2015-01-01

    textabstractMeier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia

  4. Climate change, land use and land surveyors

    NARCIS (Netherlands)

    van der Molen, P.; Mitchell, D.

    2016-01-01

    Research reveals that the land sector is a major emitter of greenhouse gases. But the land sector has also potential to reduce emissions. Different from other emission sectors like energy and transport, the land sector (in particular the rural area including forests) has the potential to also remove

  5. Climate change, land use and land surveyors

    OpenAIRE

    van der Molen, P.; Mitchell, D.

    2016-01-01

    Research reveals that the land sector is a major emitter of greenhouse gases. But the land sector has also potential to reduce emissions. Different from other emission sectors like energy and transport, the land sector (in particular the rural area including forests) has the potential to also remove greenhouse gases from the atmosphere through sequestration and storage. This requires land use, land use change and forestry to be managed with respect to climate change goals. Carbon storage has ...

  6. Caspar Wessel (1745-1818). Surveyor and Mathematician

    DEFF Research Database (Denmark)

    Branner, Bodil; Johansen, Nils Voje

    1999-01-01

    as 1787. In 1797 his mathematical paper "On the Analytical Representation of Direction. An Attempt Applied Chiefly to Solving Plane and Spherical Polygons" (in Danish) was accepted for publication in the Collected Papers of the Academy. The articleis today recognised as the first to contain...

  7. Effective utilisation of generation Y Quantity Surveyors

    African Journals Online (AJOL)

    together and tested by means of open interview discussions with senior QS professionals. ... employers could better utilise generation Y employees. 2. Literature review .... Literature was reviewed by using search engines (Emerald, Business.

  8. Rapid screening for nuclear genes mutations in isolated respiratory chain complex I defects.

    Science.gov (United States)

    Pagniez-Mammeri, Hélène; Lombes, Anne; Brivet, Michèle; Ogier-de Baulny, Hélène; Landrieu, Pierre; Legrand, Alain; Slama, Abdelhamid

    2009-04-01

    Complex I or reduced nicotinamide adenine dinucleotide (NADH): ubiquinone oxydoreductase deficiency is the most common cause of respiratory chain defects. Molecular bases of complex I deficiencies are rarely identified because of the dual genetic origin of this multi-enzymatic complex (nuclear DNA and mitochondrial DNA) and the lack of phenotype-genotype correlation. We used a rapid method to screen patients with isolated complex I deficiencies for nuclear genes mutations by Surveyor nuclease digestion of cDNAs. Eight complex I nuclear genes, among the most frequently mutated (NDUFS1, NDUFS2, NDUFS3, NDUFS4, NDUFS7, NDUFS8, NDUFV1 and NDUFV2), were studied in 22 cDNA fragments spanning their coding sequences in 8 patients with a biochemically proved complex I deficiency. Single nucleotide polymorphisms and missense mutations were detected in 18.7% of the cDNA fragments by Surveyor nuclease treatment. Molecular defects were detected in 3 patients. Surveyor nuclease screening is a reliable method for genotyping nuclear complex I deficiencies, easy to interpret, and limits the number of sequence reactions. Its use will enhance the possibility of prenatal diagnosis and help us for a better understanding of complex I molecular defects.

  9. Design Factors Influencing Quality of Building Projects in Nigeria: Consultants' Perception

    Directory of Open Access Journals (Sweden)

    Lukumon Oyedele

    2012-11-01

    Full Text Available Various factors identified from the literature that caninfluence quality of building projects in Nigeria have beenstudied by means of questionnaire survey sent to architects,engineers and quantity surveyors in the industry. From atotal response of 107 consultants, the importance of eachfactor was obtained via severity and frequency responsesof the factors. Data analysis includes comparisons ofranking among consultants using severity, frequency andimportance indexes, correlation analysis, and percentagerank agreement factor (PRAF to measure the agreement inthe importance ranking among the consultants.Correlation results between the professionals are architects/quantity surveyors (0.75, architects/engineers (0.21 ,and engineers/quantity surveyors (0.24. The percentagerank agreement factor (PRAF shows that the five mostimportant factors affecting quality are 'design changes'(78.9%; 'inadequate involvement of other professionalsduring the design stage' (78.9%; 'insufficient andunrealistic constraints of project cost' (71.1 %; 'poor levelof commitment to quality improvement among designprofessionals' (63.2%; and 'making design decisions oncost and not value of work' (55.3%. The results of this studywould provide feedback for the clients, project and qualitymangers and all the consultants in the industry, so thateffective management of quality can be ensured from theconceptual-design stage of the project.

  10. Meier-Gorlin syndrome Clinical genetics and genomics

    NARCIS (Netherlands)

    De Munnik, Sonja A.; Hoefsloot, Elisabeth H.; Roukema, Jolt; Schoots, Jeroen; Knoers, Nine Vam; Brunner, Han G.; Jackson, Andrew P.; Bongers, Ernie Mhf

    2015-01-01

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females

  11. Meier-Gorlin syndrome

    NARCIS (Netherlands)

    Munnik, S.A. de; Hoefsloot, E.H.; Roukema, J.; Schoots, J.; Knoers, N.V.A.M.; Brunner, H.G.; Jackson, A.P.; Bongers, E.M.H.F.

    2015-01-01

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females

  12. Il geometra del mare

    Directory of Open Access Journals (Sweden)

    Elisabetta Panina

    2015-03-01

    Full Text Available The course concern a post graduate diploma for Surveyors wanted by the Ministry of Education, University and Research (MIUR, the Ligurian Region, the Provincial College Surveyors of Genoa and the Naval Academy of Genoa, in order to train professionals' figure able to manage in a qualified way the main activities related to the management of coastal areas both marine, river and lake, to the protection and safeguarding of coasts, ports and artifacts and, again, in order to create maintenance operations and realization that take account of the adjustments and functional evolution of maritime transport.

  13. GWA study data mining and independent replication identify cardiomyopathy-associated 5 (CMYA5) as a risk gene for schizophrenia

    NARCIS (Netherlands)

    Chen, X.; Lee, G.; Maher, B. S.; Fanous, A. H.; Chen, J.; Zhao, Z.; Guo, A.; van den Oord, E.; Sullivan, P. F.; Shi, J.; Levinson, D. F.; Gejman, P. V.; Sanders, A.; Duan, J.; Owen, M. J.; Craddock, N. J.; O'Donovan, M. C.; Blackman, J.; Lewis, D.; Kirov, G. K.; Qin, W.; Schwab, S.; Wildenauer, D.; Chowdari, K.; Nimgaonkar, V.; Straub, R. E.; Weinberger, D. R.; O'Neill, F. A.; Walsh, D.; Bronstein, M.; Darvasi, A.; Lencz, T.; Malhotra, A. K.; Rujescu, D.; Giegling, I.; Werge, T.; Hansen, T.; Ingason, A.; Nöethen, M. M.; Rietschel, M.; Cichon, S.; Djurovic, S.; Andreassen, O. A.; Cantor, R. M.; Ophoff, R.; Corvin, A.; Morris, D. W.; Gill, M.; Pato, C. N.; Pato, M. T.; Macedo, A.; Gurling, H. M. D.; McQuillin, A.; Pimm, J.; Hultman, C.; Lichtenstein, P.; Sklar, P.; Purcell, S. M.; Scolnick, E.; St Clair, D.; Blackwood, D. H. R.; Kendler, K. S.; Kahn, René S.; Linszen, Don H.; van Os, Jim; Wiersma, Durk; Bruggeman, Richard; Cahn, Wiepke; de Haan, Lieuwe; Krabbendam, Lydia; Myin-Germeys, Inez; O'Donovan, Michael C.; Kirov, George K.; Craddock, Nick J.; Holmans, Peter A.; Williams, Nigel M.; Georgieva, Lyudmila; Nikolov, Ivan; Norton, N.; Williams, H.; Toncheva, Draga; Milanova, Vihra; Owen, Michael J.; Hultman, Christina M.; Lichtenstein, Paul; Thelander, Emma F.; Sullivan, Patrick; Morris, Derek W.; O'Dushlaine, Colm T.; Kenny, Elaine; Quinn, Emma M.; Gill, Michael; Corvin, Aiden; McQuillin, Andrew; Choudhury, Khalid; Datta, Susmita; Pimm, Jonathan; Thirumalai, Srinivasa; Puri, Vinay; Krasucki, Robert; Lawrence, Jacob; Quested, Digby; Bass, Nicholas; Gurling, Hugh; Crombie, Caroline; Fraser, Gillian; Kuan, Soh Leh; Walker, Nicholas; St Clair, David; Blackwood, Douglas H. R.; Muir, Walter J.; McGhee, Kevin A.; Pickard, Ben; Malloy, Pat; Maclean, Alan W.; van Beck, Margaret; Wray, Naomi R.; Macgregor, Stuart; Visscher, Peter M.; Pato, Michele T.; Medeiros, Helena; Middleton, Frank; Carvalho, Celia; Morley, Christopher; Fanous, Ayman; Conti, David; Knowles, James A.; Ferreira, Carlos Paz; Macedo, Antonio; Azevedo, M. Helena; Pato, Carlos N.; Stone, Jennifer L.; Ruderfer, Douglas M.; Kirby, Andrew N.; Ferreira, Manuel A. R.; Daly, Mark J.; Purcell, Shaun M.; Sklar, Pamela; Chambert, Kimberly; Kuruvilla, Finny; Gabriel, Stacey B.; Ardlie, Kristin; Moran, Jennifer L.; Scolnick, Edward M.

    2011-01-01

    We conducted data-mining analyses using the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and molecular genetics of schizophrenia genome-wide association study supported by the genetic association information network (MGS-GAIN) schizophrenia data sets and performed

  14. Mars Analog Rio Tinto Experiment (MARTE): An Experimental Demonstration of Key Technologies for Searching for Life on Mars

    Science.gov (United States)

    Stoker, Carol

    2004-01-01

    The discovery of near surface ground ice by the Mars Odyssey mission and the abundant evidence for recent Gulley features observed by the Mars Global Surveyor mission support longstanding theoretical arguments for subsurface liquid water on Mars. Thus, implementing the Mars program goal to search for life points to drilling on Mars to reach liquid water, collecting samples and analyzing them with instrumentation to detect in situ organisms and biomarker compounds. Searching for life in the subsurface of Mars will require drilling, sample extraction and handling, and new technologies to find and identify biomarker compounds and search for living organisms.

  15. Obesity alters gene expression for GH/IGF-I axis in mouse mammary fat pads: differential role of cortistatin and somatostatin.

    Directory of Open Access Journals (Sweden)

    Alicia Villa-Osaba

    Full Text Available Locally produced growth hormone (GH and IGF-I are key factors in the regulation of mammary gland (MG development and may be important in breast cancer development/progression. Somatostatin (SST and cortistatin (CORT regulate GH/IGF-I axis at various levels, but their role in regulating GH/IGF-I in MGs remains unknown. Since obesity alters the expression of these systems in different tissues and is associated to MG (patho physiology, we sought to investigate the role of SST/CORT in regulating GH/IGF-I system in the MGs of lean and obese mice. Therefore, we analyzed GH/IGF-I as well as SST/CORT and ghrelin systems expression in the mammary fat pads (MFPs of SST- or CORT-knockout (KO mice and their respective littermate-controls fed a low-fat (LF or a high-fat (HF diet for 16 wks. Our results demonstrate that the majority of the components of GH/IGF-I, SST/CORT and ghrelin systems are locally expressed in mouse MFP. Expression of elements of the GH/IGF-I axis was significantly increased in MFPs of HF-fed control mice while lack of endogenous SST partially suppressed, and lack of CORT completely blunted, the up-regulation observed in obese WT-controls. Since SST/CORT are known to exert an inhibitory role on the GH/IGFI axis, the increase in SST/CORT-receptor sst2 expression in MFPs of HF-fed CORT- and SST-KOs together with an elevation on circulating SST in CORT-KOs could explain the differences observed. These results offer new information on the factors (GH/IGF-I axis involved in the endocrine/metabolic dysregulation of MFPs in obesity, and suggest that CORT is not a mere SST sibling in regulating MG physiology.

  16. An improved charging/discharging strategy of lithium batteries considering depreciation cost in day-ahead microgrid scheduling

    International Nuclear Information System (INIS)

    Zhang, Zhong; Wang, Jianxue; Wang, Xiuli

    2015-01-01

    Highlights: • A quantitative depreciation cost model is put forward for lithium batteries. • A practical charging/discharging strategy is applied to battery management. • The depth of discharge of the battery storage is scheduled more rationally. • The proposed strategy improves the cost efficiency of lithium batteries in MGs. - Abstract: An energy storage system is critical for the safe and stable operation of a microgrid (MG) and has a promising prospect in future power system. Economical and safe operation of storage system is of great significance to MGs. This paper presents an improved management strategy for lithium battery storage by establishing a battery depreciation cost model and employing a practical charging/discharging strategy. Firstly, experimental data of lithium battery cycle lives, which are functions of the depth of discharge, are investigated and synthesized. A quantitative depreciation cost model is put forward for lithium batteries from the perspective of cycle life. Secondly, a practical charging/discharging strategy is applied to the lithium battery management in MGs. Then, an optimal scheduling model is developed to minimize MG operational cost including battery depreciation cost. Finally, numerical tests are conducted on a typical grid-connected MG. Results show that the depth of discharge of storage is scheduled more rationally, and operational cost is simultaneously saved for MG under the proposed management strategy. This study helps to improve the cost efficiency and alleviate the aging process for lithium batteries.

  17. Variations in Growing-Season NDVI and Its Response to Permafrost Degradation in Northeast China

    Directory of Open Access Journals (Sweden)

    Jinting Guo

    2017-04-01

    Full Text Available Permafrost is extremely sensitive to climate change. The degradation of permafrost has strong and profound effects on vegetation. The permafrost zone of northeastern China is the second largest region of permafrost in China and lies on the south edge of the Eurasian cryolithozone. This study analyzed the spatiotemporal variations of the growing-season Normalization Difference Vegetation Index (NDVI in the permafrost zone of northeastern China and analyzed the correlation between NDVI and ground surface temperatures (GST during the years 1981–2014. Mean growing-season NDVI (MGS-NDVI experienced a marked increase of 0.003 year−1 across the entire permafrost zone. The spatial dynamics of vegetation cover had a high degree of heterogeneity on a per pixel scale. The MGS-NDVI value increased significantly (5% significance level in 80.57%, and this increase was mostly distributed in permafrost zone except for the western steppe region. Only 7.72% experienced a significant decrease in NDVI, mainly in the cultivated and steppe portions. In addition, MGS-NDVI increased significantly with increasing growing-season mean ground surface temperature (GS-MGST. Our results suggest that a warming of GS-MGST (permafrost degradation in the permafrost region of northeastern China played a positive role in increasing plant growth and activities. Although increasing ground surface temperature resulted in increased vegetation cover and growth in the short time of permafrost degradation, from the long term point of view, permafrost degradation or disappearance may weaken or even hinder vegetation activities.

  18. Stochastic multi-objective model for optimal energy exchange optimization of networked microgrids with presence of renewable generation under risk-based strategies.

    Science.gov (United States)

    Gazijahani, Farhad Samadi; Ravadanegh, Sajad Najafi; Salehi, Javad

    2018-02-01

    The inherent volatility and unpredictable nature of renewable generations and load demand pose considerable challenges for energy exchange optimization of microgrids (MG). To address these challenges, this paper proposes a new risk-based multi-objective energy exchange optimization for networked MGs from economic and reliability standpoints under load consumption and renewable power generation uncertainties. In so doing, three various risk-based strategies are distinguished by using conditional value at risk (CVaR) approach. The proposed model is specified as a two-distinct objective function. The first function minimizes the operation and maintenance costs, cost of power transaction between upstream network and MGs as well as power loss cost, whereas the second function minimizes the energy not supplied (ENS) value. Furthermore, the stochastic scenario-based approach is incorporated into the approach in order to handle the uncertainty. Also, Kantorovich distance scenario reduction method has been implemented to reduce the computational burden. Finally, non-dominated sorting genetic algorithm (NSGAII) is applied to minimize the objective functions simultaneously and the best solution is extracted by fuzzy satisfying method with respect to risk-based strategies. To indicate the performance of the proposed model, it is performed on the modified IEEE 33-bus distribution system and the obtained results show that the presented approach can be considered as an efficient tool for optimal energy exchange optimization of MGs. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Strain gradient drives shear banding in metallic glasses

    Science.gov (United States)

    Tian, Zhi-Li; Wang, Yun-Jiang; Chen, Yan; Dai, Lan-Hong

    2017-09-01

    Shear banding is a nucleation-controlled process in metallic glasses (MGs) involving multiple temporal-spatial scales, which hinders a concrete understanding of its structural origin down to the atomic scale. Here, inspired by the morphology of composite materials, we propose a different perspective of MGs as a hard particle-reinforced material based on atomic-scale structural heterogeneity. The local stable structures indicated by a high level of local fivefold symmetry (L5FS) act as hard "particles" which are embedded in the relatively soft matrix. We demonstrate this concept by performing atomistic simulations of shear banding in CuZr MG. A shear band is prone to form in a sample with a high degree of L5FS which is slowly quenched from the liquid. An atomic-scale analysis on strain and the structural evolution reveals that it is the strain gradient effect that has originated from structural heterogeneity that facilitates shear transformation zones (STZs) to mature shear bands. An artificial composite model with a high degree of strain gradient, generated by inserting hard MG strips into a soft MG matrix, demonstrates a great propensity for shear banding. It therefore confirms the critical role strain gradient plays in shear banding. The strain gradient effect on shear banding is further quantified with a continuum model and a mechanical instability analysis. These physical insights might highlight the strain gradient as the hidden driving force in transforming STZs into shear bands in MGs.

  20. Smart transactive energy framework in grid-connected multiple home microgrids under independent and coalition operations

    DEFF Research Database (Denmark)

    Marzband, Mousa; Azarinejadian, Fatemeh; Savaghebi, Mehdi

    2018-01-01

    This paper presents a smart Transactive energy (TE) framework in which home microgrids (H-MGs) can collaborate with each other in a multiple H-MG system by forming coalitions for gaining competitiveness in the market. Profit allocation due to coalition between H-MGs is an important issue...... for ensuring the optimal use of installed resources in the whole multiple H-MG system. In addition, considering demand fluctuations, energy production based on renewable resources in the multiple H-MG can be accomplished by demand-side management strategies that try to establish mechanisms to allow...... for a flatter demand curve. In this regard, demand shifting potential can be tapped through shifting certain amounts of energy demand from some time periods to others with lower expected demand, typically to match price values and to ensure that existing generation will be economically sufficient. It is also...

  1. DC Distribution Systems and Microgrids

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Anvari-Moghaddam, Amjad; Quintero, Juan Carlos Vasquez

    2017-01-01

    summarized. Due to its attractive characteristics in terms of compliance with modern generation, storage and electronic load technologies, high reliability and current carrying capacity, as well as simple control, DC systems are already an indispensable part of power systems. Moreover, the existing......A qualitative overview of different hardware topologies and control systems for DC MGs has been presented in this chapter. Some challenges and design considerations of DC protections systems have also been discussed. Finally, applications of DC MGs in emerging smart grid applications have been...... challenges such as protection issues will be effectively resolved in the near future due to fast progress of semiconductor technology which is a key enabler cheap and reliable future DC solid-state protection systems. Therefore, it is the view of the author that more and more DC systems will appear...

  2. Negative Sequence Droop Method based Hierarchical Control for Low Voltage Ride-Through in Grid-Interactive Microgrids

    DEFF Research Database (Denmark)

    Zhao, Xin; Firoozabadi, Mehdi Savaghebi; Quintero, Juan Carlos Vasquez

    2015-01-01

    . In this paper, a voltage support strategy based on negative sequence droop control, which regulate the positive/negative sequence active and reactive power flow by means of sending proper voltage reference to the inner control loop, is proposed for the grid connected MGs to ride through voltage sags under...... complex line impedance conditions. In this case, the MGs should inject a certain amount of positive and negative sequence power to the grid so that the voltage quality at load side can be maintained at a satisfied level. A two layer hierarchical control strategy is proposed in this paper. The primary...... control loop consists of voltage and current inner loops, conventional droop control and virtual impedance loop while the secondary control loop is based on positive/negative sequence droop control which can achieve power injection under voltage sags. Experimental results with asymmetrical voltage sags...

  3. The Distribution of Crystalline Hematite on Mars from the Thermal Emission Spectrometer: Evidence for Liquid Water

    Science.gov (United States)

    Christensen, P. R.; Malin, M.; Morris, D.; Bandfield, J.; Lane, M.; Edgett, K.

    2000-01-01

    Crystalline hematite on Mars has been mapped using the MGS TES. Two major, and several minor areas of significant accumulation are identified. We favor precipitation models involving Fe-rich water, providing direct mineralogic evidence for large-scale water interactions.

  4. Distributed Voltage Unbalance Compensation in Islanded Microgrids by Using Dynamic-Consensus-Algorithm

    DEFF Research Database (Denmark)

    Meng, Lexuan; Zhao, Xin; Tang, Fen

    2016-01-01

    In islanded microgrids (MGs), distributed generators (DGs) can be employed as distributed compensators for improving the power quality in the consumer side. Two-level hierarchical control can be used for voltage unbalance compensation. Primary level, consisting of droop control and virtual...

  5. A Novel Distributed Secondary Coordination Control Approach for Islanded Microgrids

    DEFF Research Database (Denmark)

    Lu, Xiaoqing; Yu, Xinghuo; Lai, Jingang

    2018-01-01

    This paper develops a new distributed secondary cooperative control scheme to coordinate distributed generators (DGs) in islanded microgrids (MGs). A finite time frequency regulation strategy containing a consensus-based distributed active power regulator is presented, which can not only guarantee...

  6. Il ruolo del topografo ieri, oggi e domani

    Directory of Open Access Journals (Sweden)

    Bryn Fosburgh

    2012-04-01

    Full Text Available Bryn Fosburgh, vice presidente di Trimble e membro del comitato esecutivo della società, fornisce ai lettori di GEOmedia la sua visione del ruolo del topografo (e dunque del geometra, in Italia al giorno d’oggi.Come cambia il suo ruolo in questo contesto? Secondo Fosburgh il topografo è diventato un professionista della gestione, interpretazione, analisi e rappresentazione dei dati geospaziali; il suo nuovo ruolo dev’essere quello di guida per tutti gli utenti che hanno a che fare con questo tipo di dati. The Role of the Surveyor Yesterday, Today and TomorrowOver the past 50 years, advances in technology have increased the efficiency of the surveying profession, particularly in meas-urement  and  data  collection.  However,  the  new  technolo-gies—coupled with the decreasing population of professional surveyors worldwide—mandate that the surveyor’s role must and will change to managing, interpreting, analyzing and por-traying geomatics data. The surveyor must guide geospatial data consumers in a variety of related disciplines on how data is collected and used while maintaining a high level of data integrity.

  7. Intra-specific variation in social organization of gorillas: implications for their social evolution.

    Science.gov (United States)

    Yamagiwa, Juichi; Kahekwa, John; Basabose, Augustin Kanyunyi

    2003-10-01

    We analysed intra-specific variation in the social organization of gorillas and ecological and social factors influencing them, based on recent data on diet, day journey length, home range size, group size and proportion of multi-male groups in three subspecies [western lowland gorillas (WLG); eastern lowland gorillas (ELG); mountain gorillas (MG)]. Median group size was similar across subspecies and across habitats, but the extraordinarily large group including >30 gorillas was only found in habitat with dense terrestrial herbaceous vegetation. Within-group competition may determine the upper limit of group size in frugivorous WLGs and ELGs in lowland habitats with scarce undergrowth. A frugivorous diet may be a causal factor of subgrouping in multi-male groups of WLGs and ELGs, while a folivorous diet may prevent subgrouping in multi-male groups of MGs. Social factors, rather than ecological factors, may play an important role in the formation of multi-male groups and their cohesiveness in MGs. High gregariousness of female gorillas and their prolonged association with a protector male are explained by their vulnerability to both infanticide (MGs) and predators (ELGs). Comparison of long-term changes in group composition and individual movements between ELGs in Kahuzi and MGs in the Virungas suggest that the occurrence of infanticide may promote kin-male association within a group. Threat of infanticide may stimulate MG females to transfer into multi-male groups to seek reliable protection and maturing MG males to stay in their natal groups after maturity. By contrast, the absence of infanticide may facilitate ELG females to associate with infants and other females at transfer and ELG males to establish large groups in a short period by taking females from their natal groups, by luring females from neighbouring groups, or by takeover of a widow group after the death of its leading male. These conditions may prevent ELG and WLG maturing males from remaining to

  8. Probabilistic energy management of a renewable microgrid with hydrogen storage using self-adaptive charge search algorithm

    International Nuclear Information System (INIS)

    Niknam, Taher; Golestaneh, Faranak; Shafiei, Mehdi

    2013-01-01

    Micro Grids (MGs) are clusters of the DER (Distributed Energy Resource) units and loads which can operate in both grid-connected and island modes. This paper addresses a probabilistic cost optimization scheme under uncertain environment for the MGs with several multiple Distributed Generation (DG) units. The purpose of the proposed approach is to make decisions regarding to optimizing the production of the DG units and power exchange with the upstream network for a Combined Heat and Power (CHP) system. A PEMFCPP (Proton Exchange Membrane Fuel cell power plant) is considered as a prime mover of the CHP system. An electrochemical model for representation and performance of the PEMFC is applied. In order to best use of the FCPP, hydrogen production and storage management are carried out. An economic model is organized to calculate the operation cost of the MG based on the electrochemical model of the PEMFC and hydrogen storage. The proposed optimization scheme comprises a self-adaptive Charged System Search (CSS) linked to the 2m + 1 point estimate method. The 2m + 1 point estimate method is employed to cover the uncertainty in the following data: the hourly market tariffs, electrical and thermal load demands, available output power of the PhotoVoltaic (PV) and Wind Turbines (WT) units, fuel prices, hydrogen selling price, operation temperature of the FC and pressure of the reactant gases of FC. The Self-adaptive CSS (SCSS) is organized based on the CSS algorithm and is upgraded by some modification approaches, mainly a self-adaptive reformation approach. In the proposed reformation method, two updating approaches are considered. Each particle based on the ability of those approaches to find optimal solutions in the past iterations, chooses one of them to improve its solution. The effectiveness of the proposed approach is verified on a multiple-DG MG in the grid-connected mode. -- Highlights: ► Consider the effect of Hydrogen produced by PEMFC on MGs. ► Combines

  9. Local structure and structural signature underlying properties in metallic glasses and supercooled liquids

    Science.gov (United States)

    Ding, Jun

    Metallic glasses (MGs), discovered five decades ago as a newcomer in the family of glasses, are of current interest because of their unique structures and properties. There are also many fundamental materials science issues that remain unresolved for metallic glasses, as well as their predecessor above glass transition temperature, the supercooled liquids. In particular, it is a major challenge to characterize the local structure and unveil the structure-property relationship for these amorphous materials. This thesis presents a systematic study of the local structure of metallic glasses as well as supercooled liquids via classical and ab initio molecular dynamics simulations. Three typical MG models are chosen as representative candidate, Cu64 Zr36, Pd82Si18 and Mg65Cu 25Y10 systems, while the former is dominant with full icosahedra short-range order and the prism-type short-range order dominate for latter two. Furthermore, we move to unravel the underlying structural signature among several properties in metallic glasses. Firstly, the temperature dependence of specific heat and liquid fragility between Cu-Zr and Mg-Cu-Y (also Pd-Si) in supercooled liquids are quite distinct: gradual versus fast evolution of specific heat and viscosity/relaxation time with undercooling. Their local structural ordering are found to relate with the temperature dependence of specific heat and relaxation time. Then elastic heterogeneity has been studied to correlate with local structure in Cu-Zr MGs. Specifically, this part covers how the degree of elastic deformation correlates with the internal structure at the atomic level, how to quantitatively evaluate the local solidity/liquidity in MGs and how the network of interpenetrating connection of icosahedra determine the corresponding shear modulus. Finally, we have illustrated the structure signature of quasi-localized low-frequency vibrational normal modes, which resides the intriguing vibrational properties in MGs. Specifically, the

  10. A Distributed Control Framework for Integrated Photovoltaic-Battery-Based Islanded Microgrids

    DEFF Research Database (Denmark)

    Golsorkhi, Mohammad; Shafiee, Qobad; Lu, Dylan Dah-Chuan

    2017-01-01

    This paper proposes a new cooperative control framework for coordination of energy storage units (ESUs), photovoltaic (PV) panels and controllable load units in singlephase low voltage microgrids (MGs). The control objectives are defined and acted upon using a two level structure; primary...

  11. Analysis and optimization of the battery energy storage systems for frequency control in autonomous microgrids, by means of hardware-in-the-loop simulations

    DEFF Research Database (Denmark)

    Serban, I.; Teodorescu, Remus; Marinescu, C.

    2012-01-01

    . The focus is on autonomous MGs that dynamically should perform similarly to the conventional power systems. During MG autonomous operation, the generators should accomplish the frequency control process, by means of their automatic generation control. However, RES-based generators have poor controllability...

  12. Generating functional analysis of batch minority games with arbitrary strategy numbers

    International Nuclear Information System (INIS)

    Shayeghi, N; Coolen, A C C

    2006-01-01

    Both the phenomenology and the theory of minority games (MG) with more than two strategies per agent are different from those of the conventional and extensively studied case S = 2. MGs with S > 2 exhibit nontrivial statistics of the frequencies with which the agents select from their available decision making strategies, with far-reaching implications. In the few theoretical MG studies with S > 2 published so far, these statistics could not be calculated analytically. This prevented solution even in ergodic stationary states; equations for order parameters could only be closed approximately, using simulation data. Here we carry out a generating functional analysis of fake history batch MGs with arbitrary values of S, and give an analytical solution of the strategy frequency problem. This leads to closed equations for order parameters in the ergodic regime, exact expressions for strategy selection statistics, and phase diagrams. Our results find perfect confirmation in numerical simulations

  13. GWA study data mining and independent replication identify cardiomyopathy-associated 5 (CMYA5) as a risk gene for schizophrenia

    DEFF Research Database (Denmark)

    Chen, X; Lee, G; Maher, B S

    2011-01-01

    We conducted data-mining analyses using the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and molecular genetics of schizophrenia genome-wide association study supported by the genetic association information network (MGS-GAIN) schizophrenia data sets and performed...... bioinformatic prioritization for all the markers with P-values ¿0.05 in both data sets. In this process, we found that in the CMYA5 gene, there were two non-synonymous markers, rs3828611 and rs10043986, showing nominal significance in both the CATIE and MGS-GAIN samples. In a combined analysis of both the CATIE...... in our Irish samples and was dropped out without further investigation. The other two markers were verified in 23 other independent data sets. In a meta-analysis of all 23 replication samples (family samples, 912 families with 4160 subjects; case-control samples, 11¿380 cases and 15¿021 controls), we...

  14. A comparative study of Mg and Pt contacts on semi-insulating GaAs: Electrical and XPS characterization

    Energy Technology Data Exchange (ETDEWEB)

    Dubecký, F., E-mail: elekfdub@savba.sk [Institute of Electrical Engineering, SAS, Dúbravská cesta 9, Bratislava, SK-84104 (Slovakia); Kindl, D.; Hubík, P. [Institute of Physics CAS, v.v.i., Cukrovarnická 10, CZ-16200 Prague (Czech Republic); Mičušík, M. [Polymer Institute, SAS, Dúbravská cesta 9, Bratislava, SK-84541 (Slovakia); Dubecký, M. [Department of Physics, Faculty of Science, University of Ostrava, 30. dubna 22, CZ-70103 Ostrava 1 (Czech Republic); Boháček, P.; Vanko, G. [Institute of Electrical Engineering, SAS, Dúbravská cesta 9, Bratislava, SK-84104 (Slovakia); Gombia, E. [IMEM-CNR, Parco area delle Scienze 37/A, Parma, I-43010 (Italy); Nečas, V. [Faculty of Electrical Engineering and Information Technology, SUT, Ilkovičova 3, Bratislava, SK-81219 (Slovakia); Mudroň, J. [Department of Electronics, Academy of Armed Forces, Demänová 393, Liptovský Mikuláš, SK-03106 (Slovakia)

    2017-02-15

    Highlights: • Explored were diodes with full-area low/high work function metal contacts on semi-insulating GaAs (S). • The Mg-S-Mg diode is promising for radiation detectors for its low high-field current. • The XPS analysis of Mg-S interface shows presence of MgO instead of Mg metal. - Abstract: We present a comparative study of the symmetric metal-SI GaAs-metal (M-S-M) diodes with full-area contacts on both device sides, in order to demonstrate the effect of contact metal work function in a straightforward way. We compare the conventional high work function Pt contact versus the less explored low work function Mg contact. The Pt-S-Pt, Mg-S-Mg and mixed Mg-S-Pt structures are characterized by the current-voltage measurements, and individual Pt-S and Mg-S contacts are investigated by the X-ray photoelectron spectroscopy (XPS). The transport measurements of Mg-S-Pt structure show a significant current decrease at low bias while the Mg-S-Mg structure shows saturation current at high voltages more than an order of magnitude lower with respect to the Pt-S-Pt reference. The phenomena observed in Mg-containing samples are explained by the presence of insulating MgO layer at the M-S interface, instead of the elementary Mg, as confirmed by the XPS analysis. Alternative explanations of the influence of MgO layer on the effective resistance of the structures are presented. The reported findings have potential applications in M-S-M sensors and radiation detectors based on SI GaAs.

  15. AMIGHO: Automated Metadata Ingest for GNSS Hydrology within OODT

    Data.gov (United States)

    National Aeronautics and Space Administration — GNSS sites installed by surveyors and geophysicists to measure land motions can also provide valuable and cost-efficient information about three critical hydrologic...

  16. Composition and grain size effects on the structural and mechanical properties of CuZr nanoglasses

    International Nuclear Information System (INIS)

    Adibi, Sara; Branicio, Paulo S.; Zhang, Yong-Wei; Joshi, Shailendra P.

    2014-01-01

    Nanoglasses (NGs), metallic glasses (MGs) with a nanoscale grain structure, have the potential to considerably increase the ductility of traditional MGs while retaining their outstanding mechanical properties. We investigated the effects of composition on the structural and mechanical properties of CuZr NG films with grain sizes between 3 to 15 nm using molecular dynamics simulations. Results indicate a transition from localized shear banding to homogeneous superplastic flow with decreasing grain size, although the critical average grain size depends on composition: 5 nm for Cu 36 Zr 64 and 3 nm for Cu 64 Zr 36 . The flow stress of the superplastic NG at different compositions follows the trend of the yield stress of the parent MG, i.e., Cu 36 Zr 64 yield/flow stress: 2.54 GPa/1.29 GPa and Cu 64 Zr 36 yield/flow stress: 3.57 GPa /1.58 GPa. Structural analysis indicates that the differences in mechanical behavior as a function of composition are rooted at the distinct statistics of prominent atomic Voronoi polyhedra. The mechanical behavior of NGs is also affected by the grain boundary thickness and the fraction of atoms at interfaces for a given average grain size. The results suggest that the composition dependence of the mechanical behavior of NGs follows that of their parent MGs, e.g., a stronger MG will generate a stronger NG, while the intrinsic tendency for homogeneous deformation occurring at small grain size is not affected by composition.

  17. Towards Stochastic Optimization-Based Electric Vehicle Penetration in a Novel Archipelago Microgrid.

    Science.gov (United States)

    Yang, Qingyu; An, Dou; Yu, Wei; Tan, Zhengan; Yang, Xinyu

    2016-06-17

    Due to the advantage of avoiding upstream disturbance and voltage fluctuation from a power transmission system, Islanded Micro-Grids (IMG) have attracted much attention. In this paper, we first propose a novel self-sufficient Cyber-Physical System (CPS) supported by Internet of Things (IoT) techniques, namely "archipelago micro-grid (MG)", which integrates the power grid and sensor networks to make the grid operation effective and is comprised of multiple MGs while disconnected with the utility grid. The Electric Vehicles (EVs) are used to replace a portion of Conventional Vehicles (CVs) to reduce CO 2 emission and operation cost. Nonetheless, the intermittent nature and uncertainty of Renewable Energy Sources (RESs) remain a challenging issue in managing energy resources in the system. To address these issues, we formalize the optimal EV penetration problem as a two-stage Stochastic Optimal Penetration (SOP) model, which aims to minimize the emission and operation cost in the system. Uncertainties coming from RESs (e.g., wind, solar, and load demand) are considered in the stochastic model and random parameters to represent those uncertainties are captured by the Monte Carlo-based method. To enable the reasonable deployment of EVs in each MGs, we develop two scheduling schemes, namely Unlimited Coordinated Scheme (UCS) and Limited Coordinated Scheme (LCS), respectively. An extensive simulation study based on a modified 9 bus system with three MGs has been carried out to show the effectiveness of our proposed schemes. The evaluation data indicates that our proposed strategy can reduce both the environmental pollution created by CO 2 emissions and operation costs in UCS and LCS.

  18. The sustained effect (12 months) of a single-dose vectored thermal pulsation procedure for meibomian gland dysfunction and evaporative dry eye.

    Science.gov (United States)

    Blackie, Caroline A; Coleman, Christy A; Holland, Edward J

    2016-01-01

    To evaluate the sustained effect (up to 1 year) of a single, 12-minute vectored thermal pulsation (VTP) treatment in improving meibomian gland function and dry eye symptoms in patients with meibomian gland dysfunction and evaporative dry eye. The prospective, multicenter, open-label clinical trial included 200 subjects (400 eyes) who were randomized to a single VTP treatment (treatment group) or twice-daily, 3-month, conventional warm compress and eyelid hygiene therapy (control group). Control group subjects received crossover VTP treatment at 3 months (crossover group). Effectiveness measures of meibomian gland secretion (MGS) and dry eye symptoms were evaluated at baseline and 1, 3, 6, 9, and 12 months. Subjects with inadequate symptom relief could receive additional meibomian gland dysfunction therapy after 3 (treatment group) and 6 months (crossover group). At 3 months, the treatment group had greater mean improvement in MGS (Pdry eye symptoms (P=0.0068), compared to controls. At 12 months, 86% of the treatment group had received only one VTP treatment, and sustained a mean improvement in MGS from 6.4±3.7 (baseline) to 17.3±9.1 (Pdry eye symptoms from 44.1±20.4 to 21.6±21.3 (Pdry eye symptoms from 49.1±21.0 to 24.0±23.2 (Pdry eye symptoms, over 12 months. A single VTP treatment provides significantly greater mean improvement in meibomian gland function and dry eye symptoms as compared to a conventional, twice-daily, 3-month regimen. Early VTP intervention for meibomian gland dysfunction is associated with improved treatment outcomes.

  19. Influence of anesthesia techniques of caesarean section on memory, perception and speech

    Directory of Open Access Journals (Sweden)

    Volkov O.O.

    2014-06-01

    Full Text Available In obstetrics postoperative cognitive dysfunctions may take place after caesarean section and vaginal delivery with poor results both for mother and child. The goal was to study influence of anesthesia techniques following caesarian section on memory, perception and speech. Having agreed with local ethics committee and obtained informed consent depending on anesthesia method, pregnant women were divided into 2 groups: 1st group (n=31 had spinal anesthesia, 2nd group (n=34 – total intravenous anesthesia. Spinal anesthesia: 1.8-2.2 mLs of hyperbaric 0.5% bupivacaine. ТIVА: Thiopental sodium (4 mgs kg-1, succinylcholine (1-1.5 mgs kg-1. Phentanyl (10-5-3 µgs kg-1 hour and Diazepam (10 mgs were used after newborn extraction. We used Luria’s test for memory assessment, perception was studied by test “recognition of time”. Speech was studied by test "name of fingers". Control points: 1 - before the surgery, 2 - in 24h after the caesarian section, 3 - on day 3 after surgery, 4 - at discharge from hospital (5-7th day. The study showed that initially decreased memory level in expectant mothers regressed along with the time after caesarean section. Memory is restored in 3 days after surgery regardless of anesthesia techniques. In spinal anesthesia on 5-7th postoperative day memory level exceeds that of used in total intravenous anesthesia. The perception and speech do not depend on the term of postoperative period. Anesthesia technique does not influence perception and speech restoration after caesarean sections.

  20. Plug-and-Play Design of Current Controllers for Grid-feeding Converters in DC Microgrids

    DEFF Research Database (Denmark)

    Han, Renke; Tucci, Michele; Soloperto, Raffaele

    2017-01-01

    In this paper, we address the problem of synthesizing decentralized current controllers for grid-feeding converters of current-controlled distributed generation units (CDGUs) in dc microgrids (MGs). Notably, a plug-and-play (PnP) design procedure is proposed to achieve grid-feeding current tracking...

  1. Topology identification for multiple-bus DC MicroGrids via primary control perturbations

    DEFF Research Database (Denmark)

    Angjelichinoski, Marko; Stefanovic, Cedomir; Popovski, Petar

    2017-01-01

    We propose a Least Squares Estimation procedure for estimating the admittance matrix of multi-bus DC MicroGrids (MGs). In the proposed solution, the generators simultaneously inject training signals in the form of small deterministic perturbations of the primary droop control parameters and measure...

  2. Communication-Theoretic Model of Power Talk for a Single-Bus DC Microgrid

    DEFF Research Database (Denmark)

    Angjelichinoski, Marko; Stefanovic, Cedomir; Popovski, Petar

    2016-01-01

    Power talk is a method for communication among voltage control sources (VSCs) in DC microgrids (MGs), achieved through variations of the supplied power that is incurred by modulation of the parameters of the primary control. The physical medium upon which the communication channel is established...

  3. Voltage-Level Selection of Future Two-Level LVdc Distribution Grids

    DEFF Research Database (Denmark)

    Diaz, Enrique Rodriguez; Chen, Fang; Quintero, Juan Carlos Vasquez

    2016-01-01

    significantly. Microgrids (MGs) come as a suitable solution for the installation of distributed sources in the low voltage grid, where most of the consumers are sparsely located. Microgrids ease the integration of distributed generators (DGs), especially renewable energy sources like solar panels and small wind...

  4. On Secondary Control Approaches for Voltage Regulation in DC Microgrids

    DEFF Research Database (Denmark)

    Peyghami Akhuleh, Saeed; Mokhtari, Hossein; Davari, Pooya

    2017-01-01

    Centralized or decentralized secondary controller is commonly employed to regulate the voltage drop raised by the primary controller. However, in the case of high capacity MGs and long feeders with much voltage drop on the line resistances, the conventional methods may not guarantee the voltage...

  5. Labour costs and queueing theory in retailing

    NARCIS (Netherlands)

    J.B.G. Frenk (Hans); A.R. Thurik (Roy); C.A. Bout

    1991-01-01

    textabstractIn this paper approximation results for the M/G/s queueing model are used to derive an empirically verified shop type dependent non-homogeneous relation between labour volume and sales in retail trade. Moreover, we formulate the retailer's labour management as a formal minimization

  6. Energy storage systems impact on the short-term frequency stability of distributed autonomous microgrids, an analysis using aggregate models

    DEFF Research Database (Denmark)

    Serban, Ioan; Teodorescu, Remus; Marinescu, Corneliu

    2013-01-01

    This study analyses the integration impact of battery energy storage systems (BESSs) on the short-term frequency control in autonomous microgrids (MGs). Short-term frequency stability relates with the primary or speed control level, as defined in the regulations of the classical grids. The focus...

  7. At R802

    CERN Multimedia

    1974-01-01

    The photo shows the magnet (blue) of the spectrometer covering nearly the complete solid angle used by the CERN-Rome Collaboration to study negative particles at angles close to 0 deg with respect to one of the two colliding beams (Annual Report 1974, p. 108 and Photo Archive 7402246). Particles were identified by four threshold Cerenkov counters (on the left, bottom) and their trajectories were determined by twelve planes of MWPC (multiwire proportional chambers). The angular correlations between these particles and the over-all distribution of charged secondaries as observed in the hodoscope of R801 were also determined. On the centre a surveyor.

  8. Electronic distance measurement: an introduction

    National Research Council Canada - National Science Library

    Rüeger, J. M

    1990-01-01

    .... It is excellently suited as a text for undergraduate and graduate students and as an invaluable reference for practicing surveyors, geodesists and other scientists using EDM as a measuring tool...

  9. Monitor and Control of the Deep-Space network via Secure Web

    Science.gov (United States)

    Lamarra, N.

    1997-01-01

    (view graph) NASA lead center for robotic space exploration. Operating division of Caltech/Jet Propulsion Laboratory. Current missions, Voyagers, Galileo, Pathfinder, Global Surveyor. Upcoming missions, Cassini, Mars and New Millennium.

  10. GWA study data mining and independent replication identify cardiomyopathy-associated 5 (CMYA5) as a risk gene for schizophrenia.

    LENUS (Irish Health Repository)

    Chen, X

    2011-11-01

    We conducted data-mining analyses using the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) and molecular genetics of schizophrenia genome-wide association study supported by the genetic association information network (MGS-GAIN) schizophrenia data sets and performed bioinformatic prioritization for all the markers with P-values ≤0.05 in both data sets. In this process, we found that in the CMYA5 gene, there were two non-synonymous markers, rs3828611 and rs10043986, showing nominal significance in both the CATIE and MGS-GAIN samples. In a combined analysis of both the CATIE and MGS-GAIN samples, rs4704591 was identified as the most significant marker in the gene. Linkage disequilibrium analyses indicated that these markers were in low LD (3 828 611-rs10043986, r(2)=0.008; rs10043986-rs4704591, r(2)=0.204). In addition, CMYA5 was reported to be physically interacting with the DTNBP1 gene, a promising candidate for schizophrenia, suggesting that CMYA5 may be involved in the same biological pathway and process. On the basis of this information, we performed replication studies for these three single-nucleotide polymorphisms. The rs3828611 was found to have conflicting results in our Irish samples and was dropped out without further investigation. The other two markers were verified in 23 other independent data sets. In a meta-analysis of all 23 replication samples (family samples, 912 families with 4160 subjects; case-control samples, 11 380 cases and 15 021 controls), we found that both markers are significantly associated with schizophrenia (rs10043986, odds ratio (OR)=1.11, 95% confidence interval (CI)=1.04-1.18, P=8.2 × 10(-4) and rs4704591, OR=1.07, 95% CI=1.03-1.11, P=3.0 × 10(-4)). The results were also significant for the 22 Caucasian replication samples (rs10043986, OR=1.11, 95% CI=1.03-1.17, P=0.0026 and rs4704591, OR=1.07, 95% CI=1.02-1.11, P=0.0015). Furthermore, haplotype conditioned analyses indicated that the association

  11. Harassment and discrimination experienced by quantity surveyors in ...

    African Journals Online (AJOL)

    relationship between job stress and harassment and discrimination .... job satisfaction (Ensher, Grant-Vallone & Donaldson, 2001: 56) and ...... income. These findings are consistent with previous research in the field of organisational justice, ...

  12. Determination of the maximum MGS mounting height : phase I crash testing.

    Science.gov (United States)

    2012-03-09

    Post-and-rail guardrail systems encounter environmental conditions, such as severe frost heave or erosion, which : may drastically affect the post embedment depth and rail mounting height. In addition, guardrail systems may be designed : to accommoda...

  13. HP-multigrid as smoother algorithm for higher order discontinuous Galerkin discretizations of advection dominated flows. Part I. Multilevel Analysis

    NARCIS (Netherlands)

    van der Vegt, Jacobus J.W.; Rhebergen, Sander

    2011-01-01

    The hp-Multigrid as Smoother algorithm (hp-MGS) for the solution of higher order accurate space-(time) discontinuous Galerkin discretizations of advection dominated flows is presented. This algorithm combines p-multigrid with h-multigrid at all p-levels, where the h-multigrid acts as smoother in the

  14. Meier-Gorlin syndrome: Growth and secondary sexual development of a microcephalic primordial dwarfism disorder

    NARCIS (Netherlands)

    de Munnik, Sonja A.; Otten, Barto J.; Schoots, Jeroen; Bicknell, Louise S.; Aftimos, Salim; Al-Aama, Jumana Y.; van Bever, Yolande; Bober, Michael B.; Borm, George F.; Clayton-Smith, Jill; Deal, Cheri L.; Edrees, Alaa Y.; Feingold, Murray; Fryer, Alan; van Hagen, Johanna M.; Hennekam, Raoul C.; Jansweijer, Maaike C. E.; Johnson, Diana; Kant, Sarina G.; Opitz, John M.; Ramadevi, A. Radha; Reardon, Willie; Ross, Alison; Sarda, Pierre; Schrander-Stumpel, Constance T. R. M.; Sluiter, A. Erik; Temple, I. Karen; Terhal, Paulien A.; Toutain, Annick; Wise, Carol A.; Wright, Michael; Skidmore, David L.; Samuels, Mark E.; Hoefsloot, Lies H.; Knoers, Nine V. A. M.; Brunner, Han G.; Jackson, Andrew P.; Bongers, Ernie M. H. F.

    2012-01-01

    MeierGorlin syndrome (MGS) is a rare autosomal recessive disorder characterized by primordial dwarfism, microtia, and patellar aplasia/hypoplasia. Recently, mutations in the ORC1, ORC4, ORC6, CDT1, and CDC6 genes, encoding components of the pre-replication complex, have been identified. This complex

  15. Meier-Gorlin syndrome: Growth and secondary sexual development of a microcephalic primordial dwarfism disorder

    NARCIS (Netherlands)

    de Munnik, S.A.; Otten, B.J.; Schoots, J.; Bicknell, L.S.; Aftimos, S.; Al-Aama, J.Y.; van Bever, Y.; Bober, M.B.; Borm, G.F.; Clayton-Smith, J.; Deal, C.L.; Edrees, A.Y.; Feingold, M.; Fryer, A.; van Hagen, J.M.; Hennekam, R.C.M.; Jansweijer, M.C.E.; Johnson, D.; Kant, S.G.; Opitz, J.M.; Ramadevi, A.R.; Reardon, W.; Ross, A.; Sarda, P.; Schrander-Stumpel, C.T.R.M.; Sluiter, A.E.; Temple, I.K.; Terhal, P.A.; Toutain, A.; Wise, C.A.; Wright, M.; Skidmore, D.L.; Samuels, M.E.; Hoefsloot, L.H.; Knoers, N.V.A.M.; Brunner, H.G.; Jackson, A.P.; Bongers, M.H.F.

    2012-01-01

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive disorder characterized by primordial dwarfism, microtia, and patellar aplasia/hypoplasia. Recently, mutations in the ORC1, ORC4, ORC6, CDT1, and CDC6 genes, encoding components of the pre-replication complex, have been identified. This

  16. Identification and assembly of genomes and genetic elements in complex metagenomic samples without using reference genomes

    DEFF Research Database (Denmark)

    Nielsen, Henrik Bjørn; Almeida, Mathieu; Juncker, Agnieszka

    2014-01-01

    of microbial genomes without the need for reference sequences. We demonstrate the method on data from 396 human gut microbiome samples and identify 7,381 co-abundance gene groups (CAGs), including 741 metagenomic species (MGS). We use these to assemble 238 high-quality microbial genomes and identify...

  17. A Novel Robust Communication Algorithm for Distributed Secondary Control of Islanded MicroGrids

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2013-01-01

    Distributed secondary control (DSC) is a new approach for MicroGrids (MGs) such that frequency, voltage and power regulation is made in each unit locally to avoid using a central controller. Due to the constrained traffic pattern required by the secondary control, it is viable to implement...

  18. Case Report: Meier-Gorlin syndrome: Report of an additional patient ...

    African Journals Online (AJOL)

    We report a 7 year old female child with the classical triad of Meier-Gorlin syndrome (MGS), (microtia, absent patella and short stature). She had the characteristic facial features, with normal mentality and defective speech, skeletal abnormalities, conductive hearing loss, cystitis and normal growth hormone level.

  19. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana. Sirus Mohammadi. Articles written in Sadhana. Volume 39 Issue 4 August 2014 pp 819-841. Optimal sizing of energy storage system for microgrids · Babak Mozafari Sirus Mohammadi · More Details Abstract Fulltext PDF. Microgrids (MGs) are Low Voltage distribution networks comprising various ...

  20. On Secondary Control Approaches for Voltage Regulation in DC Microgrids

    DEFF Research Database (Denmark)

    Peyghami, Saeed; Mokhtari, Hossein; Davari, Pooya

    2017-01-01

    Centralized or decentralized secondary controller is commonly employed to regulate the voltage drop raised by the primary controller. However, in the case of high capacity MGs and long feeders with much voltage drop on the line resistances, the conventional methods may not guarantee the voltage r...

  1. Reactive Power Management in Islanded Microgrid – Proportional Power Sharing in Hierarchical Droop Control

    DEFF Research Database (Denmark)

    Milczarek, Adam; Malinowski, Mariusz; Guerrero, Josep M.

    2015-01-01

    A microgrid (MG) is a local energy system consisting a number of energy sources (e.g. wind turbine or solar panels among others), energy storage units and loads that operate connected to the main electrical grid or autonomously. MGs provide flexibility, reduce the main electricity grid dependence...

  2. Glucose 6-phosphate compartmentation and the control of glycogen synthesis

    NARCIS (Netherlands)

    Meijer, Alfred

    2002-01-01

    Using adenovirus-mediated gene transfer into FTO-2B cells, a rat hepatoma cell line, we have overexpressed hexokinase I, (HK I), glucokinase (GK), liver glycogen synthase (LGS), muscle glycogen synthase (MGS), and combinations of each of the two glucose phosphorylating enzymes with each one of the

  3. 77 FR 51560 - Notice of Filing of Plats of Survey; North Dakota

    Science.gov (United States)

    2012-08-24

    ... Director, Bureau of Indian Affairs, Great Plains Region, Aberdeen, South Dakota, and was necessary to...: 43 U.S.C. Chap. 3. Josh Alexander, Acting Chief Cadastral Surveyor, Division of Resources. [FR Doc...

  4. Simulated body-fluid tests and electrochemical investigations on biocompatibility of metallic glasses

    International Nuclear Information System (INIS)

    Lin, C.H.; Huang, C.H.; Chuang, J.F.; Lee, H.C.; Liu, M.C.; Du, X.H.; Huang, J.C.; Jang, J.S.C.; Chen, C.H.

    2012-01-01

    This paper presents the in-vitro and electrochemical investigations of four metallic glasses (MGs) for finding potential MG-based bio-materials. The simulation body-fluid Hanks solution is utilized for testing the corrosion resistance of MGs, and microorganisms of Escherichia coli are used in testing the bio-toxicity. In addition, a simple cyclic voltammetry method is used for rapid verification of the potential electrochemical responses. It is found that the Zr-based MG can sustain in the body-fluid, exhibiting the best corrosion resistance and electrochemical stability. The microbiologic test shows that E. coli can grow on the surface of the Zr-based metallic glass, confirming the low cell toxicity of this Zr-based MG. Highlights: ► Vanadium is added in Cu–Zr–Al alloy to induce B2-CuZr formation. ► The more induced B2-CuZr phase can improve compressive plasticity. ► The plasticity improvement might be caused by B2 phase dynamic coarsening.

  5. Identification and assembly of genomes and genetic elements in complex metagenomic samples without using reference genomes.

    Science.gov (United States)

    Nielsen, H Bjørn; Almeida, Mathieu; Juncker, Agnieszka Sierakowska; Rasmussen, Simon; Li, Junhua; Sunagawa, Shinichi; Plichta, Damian R; Gautier, Laurent; Pedersen, Anders G; Le Chatelier, Emmanuelle; Pelletier, Eric; Bonde, Ida; Nielsen, Trine; Manichanh, Chaysavanh; Arumugam, Manimozhiyan; Batto, Jean-Michel; Quintanilha Dos Santos, Marcelo B; Blom, Nikolaj; Borruel, Natalia; Burgdorf, Kristoffer S; Boumezbeur, Fouad; Casellas, Francesc; Doré, Joël; Dworzynski, Piotr; Guarner, Francisco; Hansen, Torben; Hildebrand, Falk; Kaas, Rolf S; Kennedy, Sean; Kristiansen, Karsten; Kultima, Jens Roat; Léonard, Pierre; Levenez, Florence; Lund, Ole; Moumen, Bouziane; Le Paslier, Denis; Pons, Nicolas; Pedersen, Oluf; Prifti, Edi; Qin, Junjie; Raes, Jeroen; Sørensen, Søren; Tap, Julien; Tims, Sebastian; Ussery, David W; Yamada, Takuji; Renault, Pierre; Sicheritz-Ponten, Thomas; Bork, Peer; Wang, Jun; Brunak, Søren; Ehrlich, S Dusko

    2014-08-01

    Most current approaches for analyzing metagenomic data rely on comparisons to reference genomes, but the microbial diversity of many environments extends far beyond what is covered by reference databases. De novo segregation of complex metagenomic data into specific biological entities, such as particular bacterial strains or viruses, remains a largely unsolved problem. Here we present a method, based on binning co-abundant genes across a series of metagenomic samples, that enables comprehensive discovery of new microbial organisms, viruses and co-inherited genetic entities and aids assembly of microbial genomes without the need for reference sequences. We demonstrate the method on data from 396 human gut microbiome samples and identify 7,381 co-abundance gene groups (CAGs), including 741 metagenomic species (MGS). We use these to assemble 238 high-quality microbial genomes and identify affiliations between MGS and hundreds of viruses or genetic entities. Our method provides the means for comprehensive profiling of the diversity within complex metagenomic samples.

  6. Precombustion desulfurization using Microcel{trademark} and multi-gravity separator

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.H.; Luttrell, G.H.; Venkatraman, P. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)

    1994-12-31

    Studies conducted at the Center for Coal and Minerals Processing (CCMP) indicate that surface-based processes such as froth flotation are inefficient in removing pyrite from fine coal. This shortcoming has been attributed to the fact that pyrite can become hydrophobic under certain conditions and to the inability of flotation to reject middling particles. To overcome these deficiencies, a new processing scheme has been developed at CCMP which involved the use of the Microcel{trademark} flotation column in combination with a centrifugal flowing-film separator, called a Multi-Gravity Separator (MGS). The flotation column removes ash-forming minerals such as clay, while the MGS is effective in removing pyrite. Preliminary test data obtained with high-sulfur coals shows that this processing scheme can nearly double the pyritic sulfur rejection with little loss in clean coal yield. This article discusses the underlying principles of the new circuit and provides test results obtained using eastern U.S. coals.

  7. Construction of the Cylindrical Ozone Generator by Silent Discharge Method

    International Nuclear Information System (INIS)

    Agus Purwadi; Widdi Usada; Suryadi; Isyuniarto; Sri Sukmajaya

    2002-01-01

    It has been constructed the ozone generator by silent discharge method. Anode and cathode of discharge tube were made of stainless steel (SS) in the cylinder form with diameters of 22 mm and 25 mm, the length of 100 mm and 110 mm, the equal thickness of 1 mm respectively. The dielectric was made of cylinder glass with diameter of 23 cm, the length of 105 cm and the thickness of 1 mm. The testing of apparatus was carried out by using discharge voltage of 12.5 kV and frequency of 1.5 kHz. Identification of the ozone gas formation was marked by the existing of special ozone smell and the separated of iodine molecule (yellow colour) from the potassium iodide solution which contaminated gas out put from the ozonizer. By using absorbing method can be shown that the ozone production rate was 0.196 mg/s by using oxygen gas input and 0.065 mg/s by using ordinary air input. (author)

  8. MBE growth and design of II-VI heterostructures for epitaxial lift-off

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, Ian A.; Vallance, Erin C.; Prior, Kevin A. [School of Engineering and Physical Science, Heriot-Watt University, Edinburgh (United Kingdom); Moug, Richard T.; Tamargo, Maria C. [Department of Chemistry, City College of New York, New York, NY (United States)

    2012-08-15

    Epitaxial lift-off (ELO) is a post-growth process that allows the active part of a semiconductor structure to be transferred from its growth substrate to a new one. This is a well established technique for III-V semiconductors, and has previously been demonstrated for ZnSe-based alloys grown on GaAs using a metastable MgS sacrificial layer, taking advantage of the huge difference in etch rates of MgS and ZnSe. We report here the first successful extension of this process to II-VI layers grown on InP by using a MgSe sacrificial layer. By using the correct etching conditions, MgSe has been found to work effectively as a sacrificial layer. 5 x 5 mm{sup 2} square pieces of material can be lifted and deposited on glass substrates without any deterioration in the structural or optical properties; as confirmed by optical microscopy and photoluminescence (PL) measurements. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Tracer methodology: an appropriate tool for assessing compliance with accreditation standards?

    Science.gov (United States)

    Bouchard, Chantal; Jean, Olivier

    2017-10-01

    Tracer methodology has been used by Accreditation Canada since 2008 to collect evidence on the quality and safety of care and services, and to assess compliance with accreditation standards. Given the importance of this methodology in the accreditation program, the objective of this study is to assess the quality of the methodology and identify its strengths and weaknesses. A mixed quantitative and qualitative approach was adopted to evaluate consistency, appropriateness, effectiveness and stakeholder synergy in applying the methodology. An online questionnaire was sent to 468 Accreditation Canada surveyors. According to surveyors' perceptions, tracer methodology is an effective tool for collecting useful, credible and reliable information to assess compliance with Qmentum program standards and priority processes. The results show good coherence between methodology components (appropriateness of the priority processes evaluated, activities to evaluate a tracer, etc.). The main weaknesses are the time constraints faced by surveyors and management's lack of cooperation during the evaluation of tracers. The inadequate amount of time allowed for the methodology to be applied properly raises questions about the quality of the information obtained. This study paves the way for a future, more in-depth exploration of the identified weaknesses to help the accreditation organization make more targeted improvements to the methodology. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  10. The Behavior of Warm Molecules in Planet-forming Disks and CHESS: a Pathfinder UV Spectrograph for the LUVOIR Surveyor

    Science.gov (United States)

    Hoadley, Keri; France, Kevin

    2017-01-01

    Understanding the evolution of gas over the lifetime of protoplanetary disks provides us with important clues about how planet formation mechanisms drive the diversity of exoplanetary systems observed to date. In the first part of my talk, I will discuss how we use emission line observations of molecular hydrogen (H2) in the far-ultraviolet (far-UV) with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope to study the warm molecular regions (a CHESS), built as a demonstration of one component of the LUVOIR spectrograph and new technological improvements to UV optical components for the next generation of near- to far-UV astrophysical observatories. CHESS is a far-UV sounding rocket experiment designed to probe the warm and cool atoms and molecules near sites of recent star formation in the local interstellar medium. I will talk about the science goals, design, research and development (R&D) components, and calibration of the CHESS instrument. I will end by presenting the initial data reduction and results of the flight observations taken during the second launch of CHESS.

  11. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    is known as the driving force of crystallization. The driving force of crystallization () provides very important information about the glass-forming ability (GFA) of metallic glasses (MGs). Lesser the driving force of crystallization more is the GFA. The varies linearly with the critical size (). According to Battezzati and ...

  12. The queue-length in GI/G/s queues

    Directory of Open Access Journals (Sweden)

    Le Gall Pierre

    2000-01-01

    Full Text Available The distribution of the queue-length in the stationary symmetrical GI/G/s queue is given with an application to the M/G/s queue, particularly in the case of the combination of several packet traffics, with various constant service times, to dimension the buffer capacity.

  13. Understanding Active Metal Reaction Kinetics with Cu–Mg ...

    Indian Academy of Sciences (India)

    magnesium metal (Mg(s)) in the cathode and chlorine (Cl2(g)) in the anode ... der acidic (pH ≤ 4) and basic (pH≥ 9) conditions, the oxide layer is broken and its .... and high ionic strength of the environment (such as sea water. ([Cl−] = from ...

  14. Optimal sizing of energy storage system for microgrids

    Indian Academy of Sciences (India)

    Microgrids (MGs) are Low Voltage distribution networks comprising various distributed generators (DG), storage devices and controllable loads that can operate either interconnected or isolated from the main distribution grid as a controlled entity. Energy storage system (ESS) is a vital part of an MG. In this paper, a ...

  15. Lunar dust transport and potential interactions with power system components

    International Nuclear Information System (INIS)

    Katzan, C.M.; Edwards, J.L.

    1991-11-01

    The lunar surface is covered by a thick blanket of fine dust. This dust may be readily suspended from the surface and transported by a variety of mechanisms. As a consequence, lunar dust can accumulate on sensitive power components, such as photovoltaic arrays and radiator surfaces, reducing their performance. In addition to natural mechanisms, human activities on the Moon will disturb significant amounts of lunar dust. Of all the mechanisms identified, the most serious is rocket launch and landing. The return of components from the Surveyor III provided a rare opportunity to observe the effects of the nearby landing of the Apollo 12 lunar module. The evidence proved that significant dust accumulation occurred on the Surveyor at a distance of 155 m. From available information on particle suspension and transport mechanisms, a series of models was developed to predict dust accumulation as a function of distance from the lunar module. The accumulation distribution was extrapolated to a future lunar lander scenario. These models indicate that accumulation is expected to be substantial even as far as 2 km from the landing site. Estimates of the performance penalties associated with lunar dust coverage on radiators and photovoltaic arrays are presented. Because of the lunar dust adhesive and cohesive properties, the most practical dust defensive strategy appears to be the protection of sensitive components from the arrival of lunar dust by location, orientation, or barriers

  16. Lunar dust transport and potential interactions with power system components

    Energy Technology Data Exchange (ETDEWEB)

    Katzan, C.M.; Edwards, J.L.

    1991-11-01

    The lunar surface is covered by a thick blanket of fine dust. This dust may be readily suspended from the surface and transported by a variety of mechanisms. As a consequence, lunar dust can accumulate on sensitive power components, such as photovoltaic arrays and radiator surfaces, reducing their performance. In addition to natural mechanisms, human activities on the Moon will disturb significant amounts of lunar dust. Of all the mechanisms identified, the most serious is rocket launch and landing. The return of components from the Surveyor III provided a rare opportunity to observe the effects of the nearby landing of the Apollo 12 lunar module. The evidence proved that significant dust accumulation occurred on the Surveyor at a distance of 155 m. From available information on particle suspension and transport mechanisms, a series of models was developed to predict dust accumulation as a function of distance from the lunar module. The accumulation distribution was extrapolated to a future lunar lander scenario. These models indicate that accumulation is expected to be substantial even as far as 2 km from the landing site. Estimates of the performance penalties associated with lunar dust coverage on radiators and photovoltaic arrays are presented. Because of the lunar dust adhesive and cohesive properties, the most practical dust defensive strategy appears to be the protection of sensitive components from the arrival of lunar dust by location, orientation, or barriers.

  17. Accuracy Assessment in Determining the Location of Corners of Building Structures Using a Combination of Various Measurement Methods

    Science.gov (United States)

    Krzyżek, Robert; Przewięźlikowska, Anna

    2017-12-01

    presented in this study. Observance of the proposed boundary conditions would allow for frequent performance of surveys of building structures by surveyors (from tie distances), while maintaining the applicable accuracy criteria. This would allow for the inclusion of surveying documentation into the national geodetic and cartographic documentation center database pursuant to the legal bases.

  18. Buckling analysis of partially corroded steel plates with irregular ...

    Indian Academy of Sciences (India)

    Department of Ocean Engineering, AmirKabir University of Technology, ... could yield some acceptance criteria to assist surveyors or designers in repair and .... Finite element model of a partially both-sided corroded plate (shell elements).

  19. Towards Stochastic Optimization-Based Electric Vehicle Penetration in a Novel Archipelago Microgrid

    Directory of Open Access Journals (Sweden)

    Qingyu Yang

    2016-06-01

    Full Text Available Due to the advantage of avoiding upstream disturbance and voltage fluctuation from a power transmission system, Islanded Micro-Grids (IMG have attracted much attention. In this paper, we first propose a novel self-sufficient Cyber-Physical System (CPS supported by Internet of Things (IoT techniques, namely “archipelago micro-grid (MG”, which integrates the power grid and sensor networks to make the grid operation effective and is comprised of multiple MGs while disconnected with the utility grid. The Electric Vehicles (EVs are used to replace a portion of Conventional Vehicles (CVs to reduce CO 2 emission and operation cost. Nonetheless, the intermittent nature and uncertainty of Renewable Energy Sources (RESs remain a challenging issue in managing energy resources in the system. To address these issues, we formalize the optimal EV penetration problem as a two-stage Stochastic Optimal Penetration (SOP model, which aims to minimize the emission and operation cost in the system. Uncertainties coming from RESs (e.g., wind, solar, and load demand are considered in the stochastic model and random parameters to represent those uncertainties are captured by the Monte Carlo-based method. To enable the reasonable deployment of EVs in each MGs, we develop two scheduling schemes, namely Unlimited Coordinated Scheme (UCS and Limited Coordinated Scheme (LCS, respectively. An extensive simulation study based on a modified 9 bus system with three MGs has been carried out to show the effectiveness of our proposed schemes. The evaluation data indicates that our proposed strategy can reduce both the environmental pollution created by CO 2 emissions and operation costs in UCS and LCS.

  20. Investigation on Wire Electrochemical Micro Machining of Ni-based Metallic Glass

    International Nuclear Information System (INIS)

    Meng, Lingchao; Zeng, Yongbin; Zhu, Di

    2017-01-01

    Highlights: • WECMM with nanosecond pulses is proposed firstly for fabricating micro complex components based on metallic glasses. • Applicable electrolyte for WECMM of the Ni-based MG is discussed. • Significantly uniform machined surface is achieved in H_2SO_4 solution. • High machining efficiency and stability are obtained experimentally by modifying pulse waveforms and electrolyte compositions. • Complex microstructures of Ni-based MG are fabricated by WECMM with optimized parameters. - Abstract: Metallic glasses (MGs) have been recognized as promising materials for realizing high-performance micro devices in micro electromechanical systems (MEMS) due to their excellent functional and structural characteristics. However, the applications of MGs are currently limited because of the difficulty of shaping them on the microscale. Wire electrochemical micro machining (WECMM) is increasingly recognized as a flexible and effective method to fabricate complex-shaped micro metal components with many advantages relative to the thermomechanical processing, which appears to be well suitable for micro shaping of MGs. We consider the example of a Ni-based MG, Ni_7_2Cr_1_9Si_7B_2, which has a typical passivation characteristic in 0.1 M H_2SO_4 solution. The transpassive process can be used for localized material removal when combined with nanosecond pulsed WECMM technique. In present work, the applicable electrolyte for WECMM of the Ni-based MG was discussed firstly. Then the voltage pulse waveform and electrolyte composition were modified to improve machining efficiency and stability. Several complex microstructures such as micro curved cantilever beam, micro gear, and micro square helix were machined with different optimized parameters.

  1. Role of Leadership in Transforming the Profession of Quantity Surveying

    Directory of Open Access Journals (Sweden)

    George Ofori

    2012-11-01

    Full Text Available The construction industry is facing a period of change. The roles ofthe professions involved in the industry in general, and of quantitysurveyors in particular, are also changing. There are opportunitiesfor surveyors to seize the initiative to broaden their involvement inprojects, and attain strategic positions within the industry. However,they will have to improve upon their skill sets and their knowledgebases. Senior quantity surveyors interviewed in Singapore sharedtheir views on the challenges facing the construction industry,and their profession. They suggested that the quantity surveyingprofession would only be able to address the pressing issues itfaces if it pays more attention to innovation and the development ofits people. It should be able to attract and retain talent. Knowledgemanagement will be of critical importance. This will be enabled andfacilitated by knowledge leadership.

  2. General Land Office_GLO_Vegetation from the Years 1832 to 1859 of the State of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The Goverment Land Office (GLO) conducted the orginal public land survey of Iowa during the period 1832 to 1859. Deputy Surveyors and their assistants produced both...

  3. Power Talk

    DEFF Research Database (Denmark)

    Stefanovic, Cedomir; Popovski, Petar; Angjelichinoski, Marko

    2015-01-01

    We introduce a novel communication strategy for DC Micro Grids (MGs), termed power talk, in which the devices communicate by modulating the power levels in the DC bus. The information is transmitted by varying the parameters that the MG units use to control the level of the common bus voltage...

  4. Coriolis mass flow rate meters for low flows

    NARCIS (Netherlands)

    Mehendale, A.

    2008-01-01

    The accurate and quick measurement of small mass flow rates (~10 mg/s) of fluids is considered an “enabling technology��? in semiconductor, fine-chemical, and food & drugs industries. Flowmeters based on the Coriolis effect offer the most direct sensing of the mass flow rate, and for this reason do

  5. Meier–Gorlin syndrome: An additional Egyptian patient with ...

    African Journals Online (AJOL)

    Rabah M. Shawky

    2016-01-23

    Jan 23, 2016 ... 1. Introduction. The Meier–Gorlin syndrome (MGS) is a rare autosomal reces- ... was 81.5 cm, weight for stature (<3rd centile) and her skull circumference was ... Polycystic ovaries also were reported in ... moderate conductive hearing loss [4]. ... et al. Meier–Gorlin syndrome genotype-phenotype studies: 35.

  6. Formal validation of supervisory energy management systems for microgrids

    DEFF Research Database (Denmark)

    Sugumar, Gayathri; Selvamuthukumaran, R.; Dragicevic, T.

    2017-01-01

    techniques are available in the literature to monitor and control the energy flows among distributed RES in MGs, formal verification of those techniques was not proposed yet. The emphasis of this paper is to design and validate energy management system for a MG which consists of a solar photovoltaic (PV...

  7. PERFORMANCE AND EMISSION STUDIES ON DI-DIESEL ENGINE FUELED WITH PONGAMIA METHYL ESTER INJECTION AND METHANOL CARBURETION

    Directory of Open Access Journals (Sweden)

    HARIBABU, N.

    2010-03-01

    Full Text Available The target of the present study is to clarify ignition characteristics, combustion process and knock limit of methanol premixture in a dual fuel diesel engine, and also to improve the trade-off between NOx and smoke markedly without deteriorating the high engine performance. Experiment was conducted to evaluate the performance and emission characteristics of direct injection diesel engine operating in duel fuel mode using Pongamia methyl ester injection and methanol carburetion. Methanol is introduced into the engine at different throttle openings along with intake air stream by a carburetor which is arranged at bifurcated air inlet. Pongamia methyl ester fuel was supplied to the engine by conventional fuel injection. The experimental results show that exhaust gas temperatures are moderate and there is better reduction of NOx, HC, CO and CO2 at methanol mass flow rate of 16.2 mg/s. Smoke level was observed to be low and comparable. Improved thermal efficiency of the engine was observed.

  8. Retention characteristics of hydrogen isotopes in JT-60U

    International Nuclear Information System (INIS)

    Masaki, K.; Sugiyama, K.; Hayashi, T.; Ochiai, K.; Gotoh, Y.; Shibahara, T.; Hirohata, Y.; Oya, Y.; Miya, N.; Tanabe, T.

    2005-01-01

    Erosion/deposition distribution and hydrogen isotope behavior in the JT-60U plasma-facing wall were investigated. Distribution of the tritium, which was produced by D-D nuclear reaction, was not correlated with erosion/deposition distribution. The tritium distribution can be explained by the distribution of high-energy tritium ion-implantation due to ripple loss. Deuterium distribution in the divertor region was different from the tritium distribution and not well correlated with the deposition. The highest D/C was ∼0.05 at the bottom of the outer dome wing, which is much less than that observed in other tokamaks. For the deuterium retention, at least two retention processes (ion-implantation and co-deposition) were found on the dome region. The systematic dust collection gave the small amount of dust (∼7 g: 0.2 mg/s production) in the whole vessel of JT-60U. Deposition was observed at the remote area of the outer divertor region

  9. Genetic diversity of improved salt tolerant calli of maize (Zea mays L.) using RAPD

    Science.gov (United States)

    Saputro, Triono Bagus; Dianawati, Siti; Sholihah, Nur Fadlillatus; Ermavitalini, Dini

    2017-06-01

    Maize is one of important cultivated plants in the world, in terms of production rates, utilization rates and demands. Unfortunately, the increment of demands were not followed by the increase of production rates since the cultivation area were significantly decrease. Coastal area is the marginal land that have a good potential to extend the cultivation area. The main challenge of this area is the high content of salt. The aims of this research were try to induce a new varian of local maize through in vitro culture and observe its genetic variation using RAPD. Bluto variety from Madura island was used as an explant in callus induction. Induction of callus were conducted using MS basal medium supplemented with 3 mg/L of 2,4 D under dark condition. While the selection stage was conducted using MS basal medium supplemented with 3 mg/L of 2,4 D with the addition of various concentration of NaCl (0 mg/L; 2500 mg/L; 5000 mg/L; and 7500 mg/L). The research were arranged in a completely randomized design with three replications. The exposion of NaCl were significantly decrease the mass of maize callus. The highest addition of callus weight was 210 mgs in control treatment, while the lowest is in 7500 mg/L with 3 mgs. The RAPD technique was utilized to characterize the genotype of maize callus. Out of five primers, only three primers can produce polymorphic bands named OPA10, OPB07 and OPC02. Taken together, the surviving callus of Bluto varians can be further developed as potential somaclone that has high tolerance to salt stress.

  10. An integrated fiber and stone basket device for use in Thulium fiber laser lithotripsy

    Science.gov (United States)

    Wilson, Christopher R.; Hutchens, Thomas C.; Hardy, Luke A.; Irby, Pierce B.; Fried, Nathaniel M.

    2014-03-01

    The Thulium fiber laser (TFL) is being explored as an alternative laser lithotripter to the Holmium:YAG laser. The TFL's superior near-single mode beam profile enables higher power transmission through smaller fibers with reduced proximal fiber tip damage. Recent studies have also reported that attaching hollow steel tubing to the distal fiber tip decreases fiber degradation and burn-back without compromising stone ablation rates. However, significant stone retropulsion was observed, which increased with pulse rate. In this study, the hollow steel tip fiber design was integrated with a stone basket to minimize stone retropulsion during ablation. A device was constructed consisting of a 100-μm-core, 140-μm-OD silica fiber outfitted with 5-mm-long stainless steel tubing at the distal tip, and integrated with a 1.3-Fr (0.433-mm-OD) disposable nitinol wire basket, to form an overall 1.9-Fr (0.633-mm- OD) integrated device. This compact design may provide several potential advantages including increased flexibility, higher saline irrigation rates through the ureteroscope working channel, and reduced fiber tip degradation compared to separate fiber and stone basket manipulation. TFL pulse energy of 31.5 mJ with 500 μs pulse duration and pulse rate of 500 Hz was delivered through the integrated fiber/basket device in contact with human uric acid stones, ex vivo. TFL stone ablation rates measured 1.5 +/- 0.2 mg/s, comparable to 1.7 +/- 0.3 mg/s (P > 0.05) using standard bare fiber tips separately with a stone basket. With further development, this device may be useful for minimizing stone retropulsion, thus enabling more efficient TFL lithotripsy at higher pulse rates.

  11. Article 5

    African Journals Online (AJOL)

    recommended that the authorities regulating the practice of Estate surveyors and Valuers in Nigeria should make effort to ... Should valuation practice leave valuers' clients with the ..... Special Reference to Years Purchase (Y. P.) A Research ...

  12. Dairy cows produce cytokine and cytotoxic T cell responses following vaccination with an antigenic fraction from Streptococcus uberis.

    Science.gov (United States)

    Wedlock, D Neil; Buddle, Bryce M; Williamson, John; Lacy-Hulbert, S Jane; Turner, Sally-Anne; Subharat, Supatsak; Heiser, Axel

    2014-07-15

    Streptococcus uberis is a major cause of mastitis in dairy cows worldwide and currently, there is no vaccine commercially available against this form of mastitis. In the current study, cell-free extracts (CFE) were prepared from each of three different S. uberis strains, designated as #3, #24 and #363 representative of the three main sequence types of S. uberis that cause mastitis in New Zealand. These proteins were formulated into vaccines with Emulsigen-D and the immunogenicity of the vaccines was determined in both calves and dairy cows. Two groups of calves (n=5/group) were vaccinated subcutaneously with CFE from strain #24 or strains #3, #24 and #363 formulated with Emulsigen-D, respectively. A third group (n=5) was vaccinated with CFE from the three strains formulated with Emulsigen-D and also containing recombinant bovine granulocyte macrophage colony-stimulating factor while, a control group (n=5) was not vaccinated. Vaccinated animals produced strong antibody responses to the S. uberis antigens and an antigen-specific cytotoxic effect against blood monocytes/macrophages that had phagocytosed S. uberis, with no significant differences in responses observed between the three vaccinated groups. In a second trial, the safety and immunogenicity of the vaccine containing CFE from all three strains of S. uberis and Emulsigen-D was determined in dairy cows. A group of six cows were vaccinated subcutaneously at 3 and 1 week prior to dry off and revaccinated 2-3 weeks before calving. Immune responses in blood and mammary gland secretions (MGS) were monitored during the dry period and in the subsequent lactation. The vaccine was well tolerated with no adverse effect from vaccination observed in any of the cows. Vaccination induced an antigen-specific cytotoxic effect against blood monocytes/macrophages that had phagocytosed S. uberis, moderate antigen-specific IFN-γ responses in blood and strong antibody responses in both blood and MGS. In conclusion, the results

  13. Dusty plasma in the region of the lunar terminator

    Energy Technology Data Exchange (ETDEWEB)

    Popel, S. I., E-mail: popel@iki.rssi.ru; Zelenyi, L. M. [Russian Academy of Sciences, Space Research Institute (Russian Federation); Atamaniuk, B. [Polish Academy of Sciences, Space Research Center (Poland)

    2016-05-15

    Dusty plasma in the region of the lunar terminator is considered. It is shown that, in this region, a structure resembling a plasma sheath forms near the lunar surface. This sheath creates a potential barrier, due to which electrons over the illuminated part of the Moon are confined by electrostatic forces. The width of the sheath-like structure is on the order of the ion Debye length. In this structure, significant (about several hundred V/m) electric fields arise, which lift charged micron-size dust grains to heights of several tens of centimeters. The suggested effect may be used to explain the glow observed by the Surveyor spacecraft over the lunar terminator.

  14. Monitoring of stability of ASG-EUPOS network coordinates

    Science.gov (United States)

    Figurski, M.; Szafranek, K.; Wrona, M.

    2009-04-01

    ASG-EUPOS (Active Geodetic Network - European Position Determination System) is the national system of precise satellite positioning in Poland, which increases a density of regional and global GNSS networks and is widely used by public administration, national institutions, entrepreneurs and citizens (especially surveyors). In near future ASG-EUPOS is to take role of main national network. Control of proper activity of stations and realization of ETRS'89 is a necessity. User of the system needs to be sure that observations quality and coordinates accuracy are high enough. Coordinates of IGS (International GNSS Service) and EPN (European Permanent Network) stations are precisely determined and any changes are monitored all the time. Observations are verified before they are archived in regional and global databases. The same applies to ASG-EUPOS. This paper concerns standardization of GNSS observations from different stations (uniform adjustment), examination of solutions correctness according to IGS and EPN standards and stability of solutions and sites activity

  15. The dynamics in the upper atmospheres of Mars and Titan

    Science.gov (United States)

    Bell, Jared M.

    2008-06-01

    This thesis explores the dynamics of two terrestrial bodies: Mars and Titan. At Mars, the coupled Mars General Circulation Model - Mars Thermospheric General Circulation Model (MGCM-MTGCM) is employed to investigate the phenomenon known as Mars winter polar warming. At Titan, a new theoretical model, the Titan Global Ionosphere - Thermosphere Model (T-GITM), is developed, based upon previous work by Ridley et al. [2006]. Using this new model, three separate numerical studies quantify the impacts of solar cycle, seasons, and lower boundary zonal winds on the Titan thermosphere structure and dynamics. At Mars, this thesis investigates thermospheric winter polar warming through three major studies: (1) a systematic analysis of vertical dust mixing in the lower atmosphere and its impact upon the dynamics of the lower thermosphere (100-130 km), (2) an interannual investigation utilizing three years of lower atmosphere infrared (IR) dust optical depth data acquired by the Thermal Emission Spectrometer (TES) instrument on board Mars Global Surveyor (MGS), and finally (3) a brief study of the MTGCM's response to variations in upward propagating waves and tides from the lower atmosphere. Ultimately, this investigation suggests that an interhemispheric summer-to-winter Hadley circulation, originating in the lower atmosphere and extending into the upper atmosphere, is responsible for thermospheric winter polar warming [ Bell etal. , 2007]. A major branch of this thesis builds upon the previous work of Müller-Wodarg et al. [2000], Müller-Wodarg et al. [2003], M7uuml;ller-Wodarg et al. [2006], and Yelle et al. [2006] as it attempts to explain the structures in Titan's upper atmosphere, between 500-1500 km. Building also upon the recent development of GITM by Ridley et al. [2006], this thesis presents a new theoretical framework, T-GITM. This model is then employed to conduct a series of numerical experiments to quantify the impacts of the solar cycle, the season, and the

  16. Buried CO2 Ice traces in South Polar Layered Deposits of Mars detected by radar sounder

    Science.gov (United States)

    Castaldo, L.; Mège, D.; Orosei, R.; Séjourné, A.

    2014-12-01

    SHARAD (SHAllow RADar) is the subsurface sounding radar provided by the Italian Space Agency (ASI) as a facility instrument to NASA's 2005 Mars Reconnaissance Orbiter (MRO). The Reduced Data Record of SHARAD data covering the area of the South Polar Layered Deposits (SPLD), has been used. The elaboration and interpretation of the data, aimed to estimate electromagnetic properties of surface layers, has been performed in terms of permittivity. The theory of electromagnetic scattering from fractal surfaces, and the estimation of geometric parameters from topographic data by Mars Orbiter Laser Altimeter (MOLA) which was one of five instruments on board the Mars Global Surveyor (MGS) spacecraft, has been used. A deep analysis of inversion has been made on all Mars and extended to the South Polar Caps in order to extract the area with a permittivity constant of CO2 ice. Several corrections have been applied to the data, moreover the calibration of the signal requires the determination of a constant that takes into account the power gain due to the radar system and the surface in order to compensate the power losses due to the orbitographic phenomena. The determination of regions with high probability of buried CO2 ice in the first layer of the Martian surface, is obtained extracting the real part of the permittivity constant of the CO2 ice (~2), estimated by other means. The permittivity of CO2ice is extracted from the Global Permittivity Map of Mars using the global standard deviation of itself as following: ɛCO2ice=ɛCO2ice+ Σ (1)where Σ=±std(ɛMapMars)/2Figure 1(a) shows the south polar areas where the values of the permittivity point to the possibility of a CO2 ice layer. Figure 1(b) is the corresponding geologic map. The comparison between the two maps indicates that the area with probable buried CO2 overlaps Hesperian and Amazonian polar units (Hp, Hesperian plains-forming deposits marked by narrow sinuous, anabranching ridges and irregular depressions, and

  17. The Athena Mars Rover Science Payload

    Science.gov (United States)

    Squyes, S. W.; Arvidson, R.; Bell, J. F., III; Carr, M.; Christensen, P.; DesMarais, D.; Economou, T.; Gorevan, S.; Klingelhoefer, G.; Haskin, L.

    1998-01-01

    .28 mrad/pixel, nearly a factor of four higher than that of the Mars Pathfinder and Mars Surveyor '98 cameras. Image compression will be performed using a wavelet compression algorithm. The Mini-Thermal Emission Spectrometer (Mini-TES) is a point spectrometer operating in -the thermal IR. It produces high spectral resolution (5 /cm) image cubes with a wavelength range of 5-40 gm, a nominal signal/noise ratio of 500:1, and a maximum angular resolution of 7 mrad (7 cm at a distance of 10 in). The wavelength region over which it operates samples the diagnostic fundamental absorption features of rockforming minerals, and also provides some capability to see through dust coatings that could tend to obscure spectral features. The mineralogical information that Mini-TES provides will be used to select from a distance the rocks and soils that will be investigated in more detail and ultimately sampled. Mini-TES is derived from the MO/MGS TES instrument, but is significantly smaller and simpler. The instrument uses an 8-cm Cassegrain telescope, a Michelson interferometer, and uncooled pyroelectric detectors. Along with its mineralogical capabilities, Mini-TES can provide information on the thermophysical properties of rocks and soils. Viewing upward, it can also provide temperature profiles through the martian atmospheric boundary layer. Elemental and Mineralogical Composition: Once promising samples have been identified from a distance using Pancam/Mini-TES, they will be studied in detail using up to three compositional sensors that can be placed directly against them by an Instrument Arm. The two compositional sensors, presently on the payload are an Alpha-Proton-X-Ray Spectrometer (APXS), and a Mossbauer Spectrometer. The APXS is derived closely from the instrument that flew on Mars Pathfinder. Radioactive alpha sources and three detection modes (alpha, proton, and x-ray) provide elemental abundances of rocks and soils to complement and constrain mineralogical data. The Athena

  18. Hull-Mounted (shipboard) Acoustic Doppler Current Profiler (ADCP) data collected during shipboard surveys during 2010 and 2011 in Vieques Sound, Virgin Passage and surrounding regions (NODC Accession 0088063)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Teledyne RD Instruments Ocean Surveyor 150kHz and Workhorse 300kHz ADCPs were utilized during cruises conducted between March 2010 and April 2011 in Vieques Sound,...

  19. Follow up of acute gonococcal urethritis in males treated with norfloxacin

    Directory of Open Access Journals (Sweden)

    Chari KVR

    1994-01-01

    Full Text Available This subject was undertaken to confirm the efficacy of norfloxacin in acute gonorrhoea and to note the relapse if any during the follow up period of 3 months. 27 male patients suffering from acute gonorrhoea were treated with 800 mgs of norfloxacin as single oral dose. In all cases, gonococci disappeared from urethral smears by 8 hours, urethral discharge subsided by 72 hrs, urine on naked eye examination cleared in 4 days except in 1 case and burning micturition subsided by 7 days. Cure rate was 100% in the study. No relapse was found at the end of follow up of 3 months. No adverse reactions were observed to norfloxacin except headache in 2 cases. Norfloxacin was safe and effective in the treatment of acute gonorrhoea.

  20. Smart Power Management of DC Microgrids in Future Milligrids

    DEFF Research Database (Denmark)

    Peyghami, Saeed; Mokhtari, Hossein; Davari, Pooya

    2016-01-01

    In this paper a novel droop approach for power management in low voltage dc MicroGrids (MGs) based on a master-slave concept is presented. A virtual frequency is injected by a master unit, which is proportional to its output power. Other slave units determine their output power according to the c...

  1. The circumstellar environment of evolved stars as traced by molecules and dust. The diagnostic power of Herschel

    Science.gov (United States)

    Lombaert, Robin

    2013-12-01

    Low-to-intermediate mass stars end their life on the asymptotic giant branch (AGB), an evolutionary phase in which the star sheds most of its mantle into the circumstellar environment through a stellar wind. This stellar wind expands at relatively low velocities and enriches the interstellar medium with elements newly made in the stellar interior. The physical processes controlling the gas and dust chemistry in the outflow, as well as the driving mechanism of the wind itself, are poorly understood and constitute the broader context of this thesis work. In a first chapter, we consider the thermodynamics of the high-density wind of the oxygen-rich star oh, using observations obtained with the PACS instrument onboard the Herschel Space Telescope. Being one of the most abundant molecules, water vapor can be dominant in the energy balance of the inner wind of these types of stars, but to date, its cooling contribution is poorly understood. We aim to improve the constraints on water properties by careful combination of both dust and gas radiative-transfer models. This unified treatment is needed due to the high sensitivity of water excitation to dust properties. A combination of three types of diagnostics reveals a positive radial gradient of the dust-to-gas ratio in oh. The second chapter deals with the dust chemistry of carbon-rich winds. The 30-mic dust emission feature is commonly identified as due to magnesium sulfide (MgS). However, the lack of short-wavelength measurements of the optical properties of this dust species prohibits the determination of the temperature profile of MgS, and hence its feature strength and shape, questioning whether this species is responsible for the 30-mic feature. By considering the very optically thick wind of the extreme carbon star LL Peg, this problem can be circumvented because in this case the short-wavelength optical properties are not important for the radial temperature distribution. We attribute the 30-mic feature to MgS, but

  2. Discovery Monday: How to measure success

    CERN Multimedia

    2003-01-01

    The last Discovery Monday which was carried out by the surveyors at CERN was a great success, one which they could not measure with their usual precision. The various entertaining as well as instructive experiments deserve a big "Thank you" to the SU group at the EST division. Children learn how to measure with the water level, like in Roman times.At CERN, photogrammetric techniques are used to precisely measure positions of complex ensembles like detectors. In Microcosm, photogrammetry is also invaluable to take the measure of visitors who can no longer cheat about their size. They were measured to a precision of one tenth of a millimetre and received a certificate.The alignment of accelerators is one of the big challenges for the surveyors at CERN. But even with good instruments, you need to have good eyes!

  3. Practical boundary surveying legal and technical principles

    CERN Document Server

    Gay, Paul

    2015-01-01

    This guide to boundary surveying provides landowners, land surveyors, students and others with the necessary foundation to understand boundary surveying techniques and the common legal issues that govern boundary establishment.  Boundary surveying is sometimes mistakenly considered a strictly technical discipline with simple and straightforward technical solutions.  In reality, boundary establishment is often a difficult and complex matter, requiring years of experience and a thorough understanding of boundary law.  This book helps readers to understand the challenges often encountered by boundary surveyors and some of the available solutions. Using only simple and logically explained mathematics, the principles and practice of boundary surveying are demystified for those without prior experience, and the focused coverage of pivotal issues such as easements and setting lot corners will aid even licensed practitioners in untangling thorny cases. Practical advice on using both basic and advanced instruments ...

  4. Browse Title Index

    African Journals Online (AJOL)

    Items 51 - 71 of 71 ... Vol 18, No 2 (2011), Strategic management: An Eastern Cape ... of clients' leadership in relation to construction health and safety in ... Vol 20, No 2 (2013), Workplace stress experienced by quantity surveyors, Abstract PDF.

  5. The History of Expropriation in Ethiopian Law

    African Journals Online (AJOL)

    Daniel_W_A

    Expropriation is a compulsory taking of land by the state for public purpose and upon .... International Federation of Surveyors. 8 Black ... In Ethiopia, the first systematic definition for the concept was given in the ...... De Droit, 28, 235-274.

  6. A magnetically responsive nanocomposite scaffold combined with Schwann cells promotes sciatic nerve regeneration upon exposure to magnetic field

    Directory of Open Access Journals (Sweden)

    Liu ZY

    2017-10-01

    Full Text Available Zhongyang Liu,1,* Shu Zhu,1,* Liang Liu,2,* Jun Ge,3,4,* Liangliang Huang,1 Zhen Sun,1 Wen Zeng,5 Jinghui Huang,1 Zhuojing Luo1 1Department of Orthopedics, Xijing Hospital, Fourth Military Medical University, Xi’an, Shaanxi, 2Department of Orthopedics, No 161 Hospital of PLA, Wuhan, Hubei, 3Department of Orthopedics, No 323 Hospital of PLA, Xi’an, Shaanxi, 4Department of Anatomy, Fourth Military Medical University, Xi’an, Shaanxi, 5Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi’an, Shaanxi, People’s Republic of China *These authors contributed equally to this work Abstract: Peripheral nerve repair is still challenging for surgeons. Autologous nerve transplantation is the acknowledged therapy; however, its application is limited by the scarcity of available donor nerves, donor area morbidity, and neuroma formation. Biomaterials for engineering artificial nerves, particularly materials combined with supportive cells, display remarkable promising prospects. Schwann cells (SCs are the absorbing seeding cells in peripheral nerve engineering repair; however, the attenuated biologic activity restricts their application. In this study, a magnetic nanocomposite scaffold fabricated from magnetic nanoparticles and a biodegradable chitosan–glycerophosphate polymer was made. Its structure was evaluated and characterized. The combined effects of magnetic scaffold (MG with an applied magnetic field (MF on the viability of SCs and peripheral nerve injury repair were investigated. The magnetic nanocomposite scaffold showed tunable magnetization and degradation rate. The MGs synergized with the applied MF to enhance the viability of SCs after transplantation. Furthermore, nerve regeneration and functional recovery were promoted by the synergism of SCs-loaded MGs and MF. Based on the current findings, the combined application of MGs and SCs with applied MF is a promising therapy for the engineering of peripheral

  7. De Novo GMNN Mutations Cause Autosomal-Dominant Primordial Dwarfism Associated with Meier-Gorlin Syndrome.

    Science.gov (United States)

    Burrage, Lindsay C; Charng, Wu-Lin; Eldomery, Mohammad K; Willer, Jason R; Davis, Erica E; Lugtenberg, Dorien; Zhu, Wenmiao; Leduc, Magalie S; Akdemir, Zeynep C; Azamian, Mahshid; Zapata, Gladys; Hernandez, Patricia P; Schoots, Jeroen; de Munnik, Sonja A; Roepman, Ronald; Pearring, Jillian N; Jhangiani, Shalini; Katsanis, Nicholas; Vissers, Lisenka E L M; Brunner, Han G; Beaudet, Arthur L; Rosenfeld, Jill A; Muzny, Donna M; Gibbs, Richard A; Eng, Christine M; Xia, Fan; Lalani, Seema R; Lupski, James R; Bongers, Ernie M H F; Yang, Yaping

    2015-12-03

    Meier-Gorlin syndrome (MGS) is a genetically heterogeneous primordial dwarfism syndrome known to be caused by biallelic loss-of-function mutations in one of five genes encoding pre-replication complex proteins: ORC1, ORC4, ORC6, CDT1, and CDC6. Mutations in these genes cause disruption of the origin of DNA replication initiation. To date, only an autosomal-recessive inheritance pattern has been described in individuals with this disorder, with a molecular etiology established in about three-fourths of cases. Here, we report three subjects with MGS and de novo heterozygous mutations in the 5' end of GMNN, encoding the DNA replication inhibitor geminin. We identified two truncating mutations in exon 2 (the 1(st) coding exon), c.16A>T (p.Lys6(∗)) and c.35_38delTCAA (p.Ile12Lysfs(∗)4), and one missense mutation, c.50A>G (p.Lys17Arg), affecting the second-to-last nucleotide of exon 2 and possibly RNA splicing. Geminin is present during the S, G2, and M phases of the cell cycle and is degraded during the metaphase-anaphase transition by the anaphase-promoting complex (APC), which recognizes the destruction box sequence near the 5' end of the geminin protein. All three GMNN mutations identified alter sites 5' to residue Met28 of the protein, which is located within the destruction box. We present data supporting a gain-of-function mechanism, in which the GMNN mutations result in proteins lacking the destruction box and hence increased protein stability and prolonged inhibition of replication leading to autosomal-dominant MGS. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  8. A robust adaptive load frequency control for micro-grids.

    Science.gov (United States)

    Khooban, Mohammad-Hassan; Niknam, Taher; Blaabjerg, Frede; Davari, Pooya; Dragicevic, Tomislav

    2016-11-01

    The goal of this study is to introduce a novel robust load frequency control (LFC) strategy for micro-grid(s) (MG(s)) in islanded mode operation. Admittedly, power generators in MG(s) cannot supply steady electric power output and sometimes cause unbalance between supply and demand. Battery energy storage system (BESS) is one of the effective solutions to these problems. Due to the high cost of the BESS, a new idea of Vehicle-to-Grid (V2G) is that a battery of Electric-Vehicle (EV) can be applied as a tantamount large-scale BESS in MG(s). As a result, a new robust control strategy for an islanded micro-grid (MG) is introduced that can consider electric vehicles׳ (EV(s)) effect. Moreover, in this paper, a new combination of the General Type II Fuzzy Logic Sets (GT2FLS) and the Modified Harmony Search Algorithm (MHSA) technique is applied for adaptive tuning of proportional-integral (PI) controller. Implementing General Type II Fuzzy Systems is computationally expensive. However, using a recently introduced α-plane representation, GT2FLS can be seen as a composition of several Interval Type II Fuzzy Logic Systems (IT2FLS) with a corresponding level of α for each. Real-data from an offshore wind farm in Sweden and solar radiation data in Aberdeen (United Kingdom) was used in order to examine the performance of the proposed novel controller. A comparison is made between the achieved results of Optimal Fuzzy-PI (OFPI) controller and those of Optimal Interval Type II Fuzzy-PI (IT2FPI) controller, which are of most recent advances in the area at hand. The Simulation results prove the successfulness and effectiveness of the proposed controller. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Long-Chain Omega-3 Polyunsaturated Fatty Acids Modulate Mammary Gland Composition and Inflammation.

    Science.gov (United States)

    Khadge, Saraswoti; Thiele, Geoffrey M; Sharp, John Graham; McGuire, Timothy R; Klassen, Lynell W; Black, Paul N; DiRusso, Concetta C; Talmadge, James E

    2018-03-25

    Studies in rodents have shown that dietary modifications as mammary glands (MG) develop, regulates susceptibility to mammary tumor initiation. However, the effects of dietary PUFA composition on MGs in adult life, remains poorly understood. This study investigated morphological alterations and inflammatory microenvironments in the MGs of adult mice fed isocaloric and isolipidic liquid diets with varying compositions of omega (ω)-6 and long-chain (Lc)-ω3FA that were pair-fed. Despite similar consumption levels of the diets, mice fed the ω-3 diet had significantly lower body-weight gains, and abdominal-fat and mammary fat pad (MFP) weights. Fatty acid analysis showed significantly higher levels of Lc-ω-3FAs in the MFPs of mice on the ω-3 diet, while in the MFPs from the ω-6 group, Lc-ω-3FAs were undetectable. Our study revealed that MGs from ω-3 group had a significantly lower ductal end-point density, branching density, an absence of ductal sprouts, a thinner ductal stroma, fewer proliferating epithelial cells and a lower transcription levels of estrogen receptor 1 and amphiregulin. An analysis of the MFP and abdominal-fat showed significantly smaller adipocytes in the ω-3 group, which was accompanied by lower transcription levels of leptin, IGF1, and IGF1R. Further, MFPs from the ω-3 group had significantly decreased numbers and sizes of crown-like-structures (CLS), F4/80+ macrophages and decreased expression of proinflammatory mediators including Ptgs2, IL6, CCL2, TNFα, NFκB, and IFNγ. Together, these results support dietary Lc-ω-3FA regulation of MG structure and density and adipose tissue inflammation with the potential for dietary Lc-ω-3FA to decrease the risk of mammary gland tumor formation.

  10. Procesamiento del grano de maíz sobre la cinética de degradación de la materia seca in vitro

    Directory of Open Access Journals (Sweden)

    Raul Velásquez V.

    2013-11-01

    Full Text Available Objetivo. Determinar el efecto del procesamiento del grano de maíz sobre la cinética de degradación y fermentación de la materia seca in vitro. Materiales y métodos. Se evaluaron cinco tratamientos, cada uno constó de una mezcla con dos especies, 70% pasto Kikuyo (Pennisetum clandestinum y 30% grano de maíz (Zea mays. El grano fue sometido a diferentes procesamientos: maíz grueso seco (MGS, maíz fino seco (MFS, maíz reconstituido (MGH, reconstituido y ensilado (MGE y ensilado con urea (MGEU. Se realizó la técnica de gas in vitro para medir parámetros de degradación y de producción de gas en diferentes horarios hasta las 48 h. Se utilizaron los modelos de Gompertz y Ørskov y McDonald para ajustar las curvas de producción de gas y degradación de MS y se evaluaron con PROC NLIN de SAS. Resultados. Los mayores volúmenes acumulados fueron obtenidos con los tratamientos MFS y MGEU con 552.5 ml y 524.03 ml, respectivamente y fueron diferentes al tratamiento MGS (p<0.05. El potencial de degradación (A+B en MGS mostró el menor valor, siendo diferente (p<0.05 a los tratamientos MFS, MGE y MGEU. Conclusiones. El tipo de procesamiento del grano de máiz molido fino, reconstituido, ensilado con y sin urea mejoraron significativamente los parámetros de fermentación y degradación de la MS. El uso de grano molido fino (2 mm puede ser reemplazado por grano grueso reconstituido y ensilado, el cual resulta más económico que la molienda fina.

  11. On the Impact of Wireless Jamming on the Distributed Secondary Microgrid Control

    DEFF Research Database (Denmark)

    Danzi, Pietro; Stefanovic, Cedomir; Meng, Lexuan

    2017-01-01

    The secondary control in direct current microgrids (MGs) is used to restore the voltage deviations caused by the primary droop control, where the latter is implemented locally in each distributed generator and reacts to load variations. Numerous recent works propose to implement the secondary con...... the secondary MG control. Compared to other denial-of-service attacks that are oriented against the tertiary control, such as economic dispatch, the attack on the secondary control presented here can be more severe, as it disrupts the basic functionality of the MG.......The secondary control in direct current microgrids (MGs) is used to restore the voltage deviations caused by the primary droop control, where the latter is implemented locally in each distributed generator and reacts to load variations. Numerous recent works propose to implement the secondary...... control in a distributed fashion, relying on a communication system to achieve consensus among MG units. This paper shows that, if the system is not designed to cope with adversary communication impairments, then a malicious attacker can apply a simple jamming of a few units of the MG and thus compromise...

  12. DISTRIBUTION OF MAXIMAL LUMINOSITY OF GALAXIES IN THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Taghizadeh-Popp, M.; Szalay, A. S. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Ozogany, K.; Racz, Z. [Institute for Theoretical Physics-HAS, Eoetvoes University, Pazmany setany 1/a, 1117 Budapest (Hungary); Regoes, E., E-mail: mtaghiza@pha.jhu.edu [European Laboratory for Particle Physics (CERN), Geneva (Switzerland)

    2012-11-10

    Extreme value statistics is applied to the distribution of galaxy luminosities in the Sloan Digital Sky Survey. We analyze the DR8 Main Galaxy Sample (MGS), as well as the luminous red galaxies (LRGs). Maximal luminosities are sampled from batches consisting of elongated pencil beams in the radial direction of sight. For the MGS, results suggest a small and positive tail index {xi}, effectively ruling out the possibility of having a finite maximum cutoff luminosity, and implying that the luminosity distribution function may decay as a power law at the high-luminosity end. Assuming, however, {xi} = 0, a non-parametric comparison of the maximal luminosities with the Fisher-Tippett-Gumbel distribution (limit distribution for variables distributed by the Schechter fit) indicates a good agreement provided that uncertainties arising from both the finite batch size and the batch-size distribution are accounted for. For a volume-limited sample of LRGs, results show that they can be described as being the extremes of a luminosity distribution with an exponentially decaying tail, provided that the uncertainties related to batch-size distribution are taken care of.

  13. A Control Strategy for Flywheel Energy Storage System for Frequency Stability Improvement in Islanded Microgrid

    Directory of Open Access Journals (Sweden)

    A. A. Khodadoost Arani

    2017-03-01

    Full Text Available The Micro-Grid (MG stability is a significant issue that must be maintained in all operational modes. Usually, two control strategies can be applied to MG; V/f control and PQ control strategies. MGs with V/f control strategy should have some Distributed Generators (DGs which have fast responses versus load changes. The Flywheel Energy Storage System (FESS has this characteristic. The FESS, which converts the mechanical energy to electrical form, can generate electrical power or absorb the additional power in power systems or MGs. In this paper, the FESS structure modeled in detail and two control strategies (V/f and PQ control are applied for this application. In addition, in order to improve the MG frequency and voltage stability, two complementary controllers are proposed for the V/f control strategy; conventional PI and Fuzzy Controllers. A typical low voltage network, including FESS is simulated for four distinct scenarios in the MATLAB/ Simulink environment. It is shown that fuzzy controller has better performance than conventional PI controller in islanded microgrid.

  14. Effects of “Danzhi Decoction” on Chronic Pelvic Pain, Hemodynamics, and Proinflammatory Factors in the Murine Model of Sequelae of Pelvic Inflammatory Disease

    Directory of Open Access Journals (Sweden)

    Xiaoling Bu

    2015-01-01

    Full Text Available Objective. To evaluate the effect of Danzhi decoction (DZD on chronic pelvic pain (CPP, hemodynamics, and proinflammatory factors of sequelae of pelvic inflammatory diseases (SPID in murine model. Methods. SPID mice were randomly treated with high-dose DZD, mid-dose DZD, low-dose DZD, aspirin, and vehicle for 3 estrous circles. The Mouse Grimace Scale (MGS was performed to evaluate CPP; blood flows of the upper genital tract, pelvic wall, and mesentery were used to assess hemodynamics in SPID mice; expressions of vascular endothelial growth factor (VEGF, angiopoietin-2 (Ang-2, and osteopontin (OPN were measured by Western blot and immunochemistry. Results. Treatment with dose-dependent DZD significantly decreased the MGS scores, accelerated blood flows of the pelvis, and reduced expressions of VEGF, Ang-2, and OPN in the upper genital tract. Conclusions and Discussions. DZD was effective in relieving CPP and improving hemodynamics of the pelvic blood-stasis microenvironment in SPID mice. There was a relationship between CPP and the pelvic blood-stasis microenvironment. Furthermore, DZD might play a positive role in the anti-inflammatory process.

  15. Process, structure, property and applications of metallic glasses

    Directory of Open Access Journals (Sweden)

    B. Geetha Priyadarshini

    2016-07-01

    Full Text Available Metallic glasses (MGs are gaining immense technological significance due to their unique structure-property relationship with renewed interest in diverse field of applications including biomedical implants, commercial products, machinery parts, and micro-electro-mechanical systems (MEMS. Various processing routes have been adopted to fabricate MGs with short-range ordering which is believed to be the genesis of unique structure. Understanding the structure of these unique materials is a long-standing unsolved mystery. Unlike crystalline counterpart, the outstanding properties of metallic glasses owing to the absence of grain boundaries is reported to exhibit high hardness, excellent strength, high elastic strain, and anti-corrosion properties. The combination of these remarkable properties would significantly contribute to improvement of performance and reliability of these materials when incorporated as bio-implants. The nucleation and growth of metallic glasses is driven by thermodynamics and kinetics in non-equilibrium conditions. This comprehensive review article discusses the various attributes of metallic glasses with an aim to understand the fundamentals of relationship process-structure-property existing in such unique class of material.

  16. Development of a proof of concept low temperature 4He Superfluid Magnetic Pump

    Science.gov (United States)

    Jahromi, Amir E.; Miller, Franklin K.

    2017-03-01

    We describe the development and experimental results of a proof of concept Superfluid Magnetic Pump in this work. This novel low temperature, no moving part pump can replace the existing bellows-piston driven 4He or 3He-4He mixture compressor/circulators used in various sub Kelvin refrigeration systems such as dilution, Superfluid pulse tube, Stirling, or active magnetic regenerative refrigerators. Due to the superior thermal transport properties of sub-Lambda 4He this pump can also be used as a simple circulator to distribute cooling over large surface areas. Our pump was experimentally shown to produce a maximum flow rate of 440 mg/s (averaged over cycle), 665 mg/s (peak) and produced a maximum pressure difference of 2323 Pa using only the more common isotope of helium, 4He. This pump worked in an ;ideal; thermodynamic state: The experimental results matched with the theoretical values predicted by a computer model. Pump curves were developed to map the performance of this pump. This successful demonstration will enable this novel pump to be implemented in suitable sub Kelvin refrigeration systems.

  17. Big Bang to Biosignatures: The LUVOIR Decadal Mission Concept

    Science.gov (United States)

    Roberge, A.; Luvoir Mission Concept Team

    2017-11-01

    The Large UV/Optical/IR Surveyor (LUVOIR) is a concept for a multi-wavelength space observatory with broad science goals. One of its major aims is to characterize habitable exoplanets around Sun-like stars and search them for signs of life.

  18. Study of ice-related flow features around Tanaica Montes, Mars: Implications for late amazonian debris-covered glaciation

    Science.gov (United States)

    Sinha, Rishitosh K.; Vijayan, S.; Bharti, Rajiv R.

    2017-11-01

    Lobate debris aprons (LDA) and lineated valley fill (LVF) have been broadly recognized in the mid-latitudes of Mars and their subsequent analyses using data from the SHAllow RADar (SHARAD) instrument has suggested evidence for contemporary ice preserved beneath these features. In this study, we conduct detailed characterization of newly identified LDA flow units within the Tanaica Montes region (39.55˚ N, 269.17˚ E) of Mars to assess and understand the similarities in their emplacement with respect to LDA flow units mapped in other regions of Mars. We utilize the Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) images and SHAllow RADar (SHARAD) datasets for geomorphic and subsurface analysis and Mars Global Surveyor (MGS) Mars Orbiter Laser Altimeter (MOLA) point tracks for topographic analysis. Geomorphic observation of LDA flow units surrounding the montes flanks and massif walls reveal integrated pattern of convergence and divergence and evidence of bending and deflection within the flow lines that resulted in concentric, loop-like flow patterns in the downslope. Brain-terrain texture and craters with varying morphological characteristics (ring-mold type) is suggestive that LDAs may be similar to ice-rich, debris-covered glaciers. MOLA point track based convex-up topographic profiles of LDAs suggest that their thickness vary in the range of ∼100-200 m in both the northwestern and southeastern portions of study region. Further, the slope values of mapped LDA surfaces within the study region are within ∼0.1˚-4˚. The extent of mapped LDAs within the study region is such that some of the low elevation (∼0.8-1.3 km) portions of montes flanks are surrounded by relatively less extent (up to ∼0.5-0.8 km) of LDA flow units. Geomorphic and topographic evidence for flow units that appear to be superposed on the main LDA body collectively suggest the possibility of episodic glacial activity in the region. Furthermore, based on the alignment of subsurface

  19. Effects of marketing group on the variability of fresh loin, belly, and fresh and processed ham quality from pigs sourced from a commercial processing facility

    Science.gov (United States)

    The objective was to quantify the effect of marketing group (MG) on the variability of primal quality. Pigs (N=7,684) were slaughtered in 3 MGs from 8 barns. Pigs were from genetic selection programs focused on lean growth (L; group 1 n=1,131; group 2 n=1,466; group 3 n=1,030) or superior meat qua...

  20. Genetic epidemiology of the Sudden Oak Death pathogen Phytophthora ramorum in California

    Science.gov (United States)

    S. Mascheretti; P.J.P. Croucher; M. Kozanitas; L. Baker; M. Garbelotto

    2009-01-01

    A total of 669 isolates of Phytophthora ramorum, the pathogen responsible for Sudden Oak Death, were collected from 34 Californian forests and from the ornamental plant-trade. Seven microsatellite markers revealed 82 multilocus genotypes (MGs) of which only three were abundant (>10%). Iteratively collapsing based upon minimum ΦST, yielded five meta-samples and five...

  1. The Cosmology Large Angular Scale Surveyor (CLASS) Telescope Architecture

    Science.gov (United States)

    Chuss, David T.; Ali, Aamir; Amiri, Mandana; Appel, John W.; Araujo, Derek; Bennett, Charles L.; Boone, Fletcher; Chan, Manwei; Cho, Hsiao-Mei; Colazo, Felipe; hide

    2014-01-01

    We describe the instrument architecture of the Johns Hopkins University-led CLASS instrument, a groundbased cosmic microwave background (CMB) polarimeter that will measure the large-scale polarization of the CMB in several frequency bands to search for evidence of inflation.

  2. Geophysical Surveys in Archaeology: Guidance for Surveyors and Sponsors

    National Research Council Canada - National Science Library

    Somers, Lewis

    2003-01-01

    The last few years have seen a significant increase in the use of geophysical techniques by archaeologists in the United States working in both academic settings and Cultural Resources Management (CRM). Since 1995...

  3. CERN's surveyors are pushing back the frontiers of precision

    CERN Multimedia

    Laurent Guiraud

    2001-01-01

    One of the SU group's major tasks is the positioning of the accelerators. The magnets must be positioned to a precision of one tenth of a millimetre. Above, the positioning of the magnets for the LHC string test.

  4. Continuing Professional Development in the quantity surveying ...

    African Journals Online (AJOL)

    1991-01-01

    Jan 1, 1991 ... The research established that quantity surveyors regarded handing in their CPD ... Surveying, Walter Sisulu University, PO Box 1421, East London, 5200, South Africa. ... Keywords: Continuing professional development, quantity surveying, perception .... In spite of this opportunity enshrined in the Act, the.

  5. The 1985 Army Experience Survey: Methodology and Recommendations for Future Administrations

    Science.gov (United States)

    1986-01-01

    Leather products, except footwear (315-317, 319) 111 Bakery products (205) 112 Sugar and confectionery products (206) 120 Beverage industries (208...Engineers, n.e.c. (1639) 013 Managers, marketing , advertising, and public relations 063 Surveyors and mapping scientists (164) (125) Mathematical and

  6. The cart before the horse: Mariner spacecraft and launch vehicles

    Science.gov (United States)

    1984-01-01

    Evolution of unmanned space exploration (Pioneer, Ranger, Surveyor, and Prospector) up to 1960, and the problems in the design and use of the Atlas Centaur launch vehicle were discussed. The Mariner Program was developed from the experience gained from the previous unmanned flights.

  7. NASA's strategy for Mars exploration in the 1990s and beyond

    Science.gov (United States)

    Huntress, W. T.; Feeley, T. J.; Boyce, J. M.

    NASA's Office of Space Science is changing its approach to all its missions, both current and future. Budget realities are necessitating that we change the way we do business and the way we look at NASA's role in the U.S. Government. These challenges are being met by a new and innovative approach that focuses on achieving a balanced world-class space science program that requires less U.S. resources while providing an enhanced role for technology and education as integral components of our Research and Development (R&D) programs. Our Mars exploration plans, especially the Mars Surveyor program, are a key feature of this new NASA approach to space science. The Mars Surveyor program will be affordable, engaging to the public with global and close-up images of Mars, have high scientific value, employ a distributed risk strategy (two launches per opportunity), and will use significant advanced technologies.

  8. WebPlotDigitizer, a polyvalent and free software to extract spectra from old astronomical publications: application to ultraviolet spectropolarimetry

    Science.gov (United States)

    Marin, F.; Rohatgi, A.; Charlot, S.

    2017-12-01

    In this contribution, we present WebPlotDigitizer, a polyvalent and free software developed to facilitate easy and accurate data extraction from a variety of plot types. We describe the numerous features of this numerical tool and present its relevance when applied to astrophysical archival research. We exploit WebPlotDigitizer to extract ultraviolet spectropolarimetric spectra from old publications that used the Hubble Space Telescope, Lick Observatory 3 m Shane telescope and Astro-2 mission to observe the Seyfert-2 AGN NGC 1068. By doing so, we compile all the existing ultraviolet polarimetric data on NGC 1068 to prepare the ground for further investigations with the future high-resolution spectropolarimeter POLLUX on-board of the proposed Large UV/Optical/Infrared Surveyor (LUVOIR) NASA mission.

  9. Understanding and Improvement of an Experiment Measuring Chemical Reaction Rates by Monitoring Volume Change of a Gas: On the Reaction between HCl(aq) and Mg(s)

    International Nuclear Information System (INIS)

    Bang, Jeong Ah; Yoon, Hee Sook; Jeong, Dae Hong; Choi, Won Ho

    2006-01-01

    In this study we analyzed and improved an experiment measuring chemical reaction rates introduced in the high school science textbooks through an understanding of the phenomena observed in carrying out the experiment. For this purpose, the contents of textbooks related to the experiment were analyzed, and the problems observed in carrying out the experiment were addressed through experimental analysis. When the experiment was carried out by the method of aquatic transposition presented in textbooks, the observed volume change of H 2 gas was delayed and chemical reaction rate was increased in the early stage of reaction period. To resolve these problems, an improved method for measuring the reaction rates was suggested. In the improved experiment the reaction rate was measured to be constant on time, which was interpreted in terms of the concentration of H + and the surface area of magnesium

  10. Environmental security of coastal seas

    International Nuclear Information System (INIS)

    Valkovic, Vladivoj; Sudac, Davorin; Nad, Karlo; Obhodas, Jasmina; Kollar, Robert; Matika, Dario

    2008-01-01

    Full text: The bottoms of the coastal seas are contaminated by many man-made objects including a variety of ammunition. This contamination is world wide spread with some areas being highly polluted presenting a serious threat to local population and to visitors as well. All littoral nations are investing lots of effort into the remediation of their coastal areas. In this report an effort to identify the nature of the object on the sea bottom is presented. Once the presence of the anomaly on the bottom of the shallow coastal sea water is confirmed (by visual identification and by using one or several sensors, namely magnetometer, sonar and optical cameras) it is necessary to establish if it contains explosive and/or chemical warfare charge. In our work we propose this to be performed by using neutron sensor installed within an underwater vessel - 'Surveyor'. When positioned above the object, or to its side, the system inspects the object for the presence of the threat material by using alpha particle tagged neutrons from the sealed tube d+t neutron generator. The inside of the first prototype of the underwater system 'Surveyor' containing neutron generator, shielding and gamma ray detector is shown in figure. The neutron generator used by the 'Surveyor' is rotated by two step motors so that different volume elements chosen by the relative position of the neutron generator and gamma ray detector could be inspected. In such a way a profile of concentrations could also be measured. The preliminary results from the laboratory tests are presented

  11. The Rare Traces of Constructional Procedures in `Practical Geometries´

    DEFF Research Database (Denmark)

    Høyrup, Jens

    2009-01-01

    measurements. As a rule it is not interested in geometrical construction, nor in the making of measurements - the fields, broadly speaking, of master builders/architects and surveyors. The paper discusses two cases - one fairly well-established, another more conjectural - where none the less "scribal...

  12. The Voyager Journey to Interstellar Space

    KAUST Repository

    Stone, Edward

    2017-01-01

    on television and the Web. Highlights of his decade of leadership as the Direction of JPL include Galileo's five-year orbital mission to Jupiter, the launch of Cassini to Saturn, the launch of Mars Global Surveyor and a new generation of Earth science satellites

  13. 7 CFR Exhibit C to Subpart C of... - Checklist of Visual Exhibits and Documentation for RRH, RCH, and LH Proposals

    Science.gov (United States)

    2010-01-01

    ... proposed development must be included. This document shall bear the seal of a professional licensed to... contracts for the professional services of an architect, engineer, land surveyor, landscape architect, site... buildings, recreation center, central cooking and dining facilities, or other similar facilities to meet...

  14. Development of a Prototype for the Assessment of the Malaysian LADM Country Profile

    NARCIS (Netherlands)

    Zulkifli, N.A.; Abdul Rahman, A.; Jamil, H.; Teng, C.H.; Tan, L.C.; Looi, K.S.; Chan, K.L.; Van Oosterom, P.J.M.

    2014-01-01

    During the last couple of years, the potential of 3D and Land Administration Domain Model (LADM, ISO 2012) based cadastral registration in Malaysiahas been investigated and described in several papers, and presented at various International Federation of Surveyor (FIG) meetings. Based on these

  15. The application of geophysics in South African coal mining and exploration

    CSIR Research Space (South Africa)

    Van Schoor, Abraham M

    2014-10-01

    Full Text Available . The target audience for such a book would be coal geologists, mine surveyors, mine planners, and other mining staff with limited or no geophysics background. This paper provides a very brief overview of the book by summarizing key sections and selected...

  16. Variation in density and diversity of species of Phytophthora in two forest stream networks

    Science.gov (United States)

    Jaesoon Hwang; Steven N. Jeffers; Steven W. Oak

    2010-01-01

    Monitoring occurrence and distribution of Phytophthora species, including Phytophthora ramorum, in forest ecosystems can be achieved in several ways including sampling symptomatic plants, infested soils, and infested streams. Collecting plant and soil samples can be laborious and time consuming due to the distance surveyors...

  17. The Cadastral Template Project

    DEFF Research Database (Denmark)

    Enemark, Stig; Steudler, Daniel; Williamson, Ian P.

    2004-01-01

    . The work of the PCGIAP-Working Group 3 ?Cadastre? is being done in collaboration with Comission 7 ?Cadastre and Land Management? of the International Federation of Surveyors (FIG), which has extensive experience in comparative cadastral studies. This article describes the creation and the content...

  18. Preparing astronomical observations and observing with OHP facilities

    Directory of Open Access Journals (Sweden)

    Patris J.

    2010-12-01

    Full Text Available In addition to the general introduction to observational astronomy given in a past paper (J. Phys. IV France, ERCA 07 (2006 pp 373-390 some tools are given to the observer. These include the general knowledge of what is going to be observed and of the instruments used. A guideline is given to prepare an observing program and to follow it as efficiently as possible. Finally, some examples are given of observations to be made by ERCA participants at OHP observatory.

  19. Meier-Gorlin syndrome

    OpenAIRE

    de Munnik, Sonja A; Hoefsloot, Elisabeth H; Roukema, Jolt; Schoots, Jeroen; Knoers, Nine V A M; Brunner, Han G; Jackson, Andrew P; Bongers, Ernie M H F

    2015-01-01

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females and urogenital anomalies, such as cryptorchidism and hypoplastic labia minora and majora. Typical facial characteristics during childhood comprise a small mouth with full lips and micro-retrognathia...

  20. Meier-Gorlin syndrome Clinical genetics and genomics

    OpenAIRE

    Munnik, Sonja; Hoefsloot, Lies; Roukema, Jolt; Schoots, Jeroen; Knoers, Nine; Brunner, H.G.; Jackson, Andrew; Bongers, Ernie

    2015-01-01

    textabstractMeier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females and urogenital anomalies, such as cryptorchidism and hypoplastic labia minora and majora. Typical facial characteristics during childhood comprise a small mouth with full lips and micro-...

Some links on this page may take you to non-federal websites. Their policies may differ from this site.