Science.gov

Sample records for barker napsas salman

  1. Design of Barker coded multiple pulse experiments

    NASA Astrophysics Data System (ADS)

    Zamlutti, C. J.

    1980-12-01

    The combination of Barker-coded pulse compression techniques with the multiple pulse technique in incoherent scatter studies of the lower ionosphere is discussed. The basic principles of both techniques are reviewed, and the combined technique is presented as consisting of the coding of each pulse of the multiple pulse scheme by a b-baud Barker code. Design considerations for measurements from which the autocorrelation function can be computed are examined for the case of the radar at Arecibo, and possible experiments for observations of sporadic E layers, man-made ionospheric modification and the nighttime E layer are proposed. It is noted that the advantage of the Barker-coded multiple pulse technique consists in the possibility of obtaining simultaneously height and frequency resolution, which is important in the observation of thin layers with narrow frequency spectra.

  2. Innovations in Ecological Psychology: Conversations with Roger and Louise Barker.

    ERIC Educational Resources Information Center

    Orzek, Ann M.

    1987-01-01

    Interviews Roger and Louise Barker and traces their work together at the Midwest Psychological Field Station in Oskaloosa, Kansas, as well as early influences on Roger Barker. Discusses practical implications for their work in education and counseling. (Author/ABB)

  3. A Powerful Theory and a Paradox: Ecological Psychologists after Barker

    ERIC Educational Resources Information Center

    Scott, M. M.

    2005-01-01

    Roger Barker, influenced by Lewin, developed a powerful theory in psychology, behavior setting theory. Paradoxically, this theory is still not widely known or understood in mainstream American psychology. Oral histories of the core group who worked with Barker were collected and examined to determine influences on them and subsequent directions in…

  4. Listening Assessment: The Watson-Barker Listening Test.

    ERIC Educational Resources Information Center

    Watson, Kittie W.; Barker, Larry L.

    An overview of listening tests and a description of the Watson-Barker Listening Test are presented in this paper. Topics covered include the readability and validity of listening tests; listening test administration; listening test criteria; creation of the Watson-Barker Listening Test; development, validation, and proper administration of this…

  5. Time multiplexing super resolution using a Barker-based array.

    PubMed

    Ilovitsh, Asaf; Preter, Eyal; Levanon, Nadav; Zalevsky, Zeev

    2015-01-15

    We propose the use of a new encoding mask in order to improve the performance of the conventional time multiplexing super resolution method. The resolution improvement is obtained using a 2D Barker-based array that is placed upon the object and shifted laterally. The Barker-based array is a 2D generalization of the standard 1D Barker code. The Barker-based array has stable autocorrelation sidelobes, making it ideal for the encoding process. A sequence of low resolution images are captured at different positions of the array, and are decoded properly using the same array. After removing the low resolution image from the resulting reconstruction, a high resolution image is established. The proposed method is presented analytically, demonstrated via numerical simulation, and validated by laboratory experiment.

  6. Time multiplexing super resolution using a Barker-based array.

    PubMed

    Ilovitsh, Asaf; Preter, Eyal; Levanon, Nadav; Zalevsky, Zeev

    2015-01-15

    We propose the use of a new encoding mask in order to improve the performance of the conventional time multiplexing super resolution method. The resolution improvement is obtained using a 2D Barker-based array that is placed upon the object and shifted laterally. The Barker-based array is a 2D generalization of the standard 1D Barker code. The Barker-based array has stable autocorrelation sidelobes, making it ideal for the encoding process. A sequence of low resolution images are captured at different positions of the array, and are decoded properly using the same array. After removing the low resolution image from the resulting reconstruction, a high resolution image is established. The proposed method is presented analytically, demonstrated via numerical simulation, and validated by laboratory experiment. PMID:25679834

  7. Checkmate: Linguistic and Literary Play in Salman Rushdie's "Haroun and the Sea of Stories"

    ERIC Educational Resources Information Center

    Bongartz, Christiane; Richey, Esther Gilman

    2010-01-01

    The authors use Noam Chomsky's theories about generative grammar to discuss the notion of linguistic creativity they believe lies at the core of storytelling as Salman Rushdie pictures it in his novel, "Haroun and the Sea of Stories." The production of meaning through the use of narrative helps explain the rules of the literary game,…

  8. Official portrait of Payload Specialist Sultan Salman Abdelazize Al-Saud

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Official portrait of Payload Specialist Sultan Salman Abdelazize Al-Saud. He is wearing the blue shuttle flight suit and holding his helmet under his arm. Behind him to the right is the Saudi Arabian flag. To his left is the American flag and a model of the Space Shuttle.

  9. Payload specialist Sultan Salman Abdelazize Al-Saud floats over pilots chair

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialist Sultan Salman Abdelazize Al-Saud floats above the pilot's station on Discovery's forward flight deck. On one side of him floats a clipboard, on the other side a fire extinguisher is attached to the wall. Through overhead windows beyond him are seen reflections of the Earth's horizon.

  10. The Predictive Value of the Watson-Barker Listening Test.

    ERIC Educational Resources Information Center

    Vander Kooi, Daryl

    Using the Watson-Barker Listening Test Form A and Form B as pretest and posttest at the freshman level, this research attempted to determine whether the two forms of the test and the differences between pretest and posttest would be significant predictors of students' final grade point average (GPA). Each form of the test was taken by 190 students…

  11. The "Watson-Barker Listening Test" for High School Students.

    ERIC Educational Resources Information Center

    Halay, Kathryn; Roberts, Charles V.

    The high school version of the Watson-Barker Listening Test was developed in response to the need for a listening test appropriate for high school students. The test was comprised of conversations that would normally occur in either the high school setting or in the home and was developed in two different versions. The test consists of five…

  12. THE BARKER HYPOTHESIS: IMPLICATIONS FOR FUTURE DIRECTIONS IN TOXICOLOGY RESEARCH

    EPA Science Inventory

    This review covers the past year’s papers germane to the Barker hypothesis. While much of the literature has centered on maternal and developmental nutrition, new findings have emerged on the ability of toxic exposures during development to impact fetal/developmental programming....

  13. Tour by Saudi prince Salman Abdelazize Al-Saud prior to mission

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Tour by Saudi prince Salman Abdelazize Al-Saud, payload specialists for STS 51-G mission, prior to mission. Al-Saud and Abdulmohsen Hamad Al-Bassam, the backup payload specialist, man the controls on the flight deck of the crew compartment trainer in the Shuttle mockup and integration laboratory (29788); the Saudi payload specialists share the hatch of the crew compartment trainer (29789); Portrait view of Abdulmohsen Hamad Al-Bassam during a visit to the Shuttle mockup and integraion laboratory (29790); Don Sirroco, left, explains the middeck facilities in the Shuttle mockup and integration laboratory (29791); Portrait view of Sultan Salman Abdelazize Al-Saud in the Shuttle Mockup and Integration laboratory (29792); The Saudi payload specialists witness a space food demonstration in the life sciences laboratory at JSC. Al-Saud (left) and Al-Bassam (second left) listen as Rita M. Rapp, food specialist, discusses three preparations of re-hydratable food for space travelers. Lynn S. Coll

  14. [Doctor Levi B. Salmans, founder of The Good Samaritan sanitarium in Guanajuato].

    PubMed

    Olivier-Toledo, Carlos; Viesca-Treviño, Carlos

    2016-01-01

    In this research we focus on the medical evangelist Levi B. Salmans, and The Good Samaritan sanitarium. Doctor Salmans lived in Mexico for about 50 years (1885-1935). During the first part of his stay, he was devoted to found churches and Methodist schools. However, from 1891 he took a turn in his career by founding dispensaries in different towns of Guanajuato to create, in 1899, the private charity association for the sick and infirm The Good Samaritan. His intense, intellectual, and practical work led him to create health journals, to train nurses, and to promote physiotherapies in accordance with the science advances of that time. By itself, this research shows that the history of medicine in Mexico still has long way to go and that Protestant communities, in favor of modernity and scientific knowledge, took a big part in shaping the history of this discipline in Mexico. PMID:27100985

  15. [Doctor Levi B. Salmans, founder of The Good Samaritan sanitarium in Guanajuato].

    PubMed

    Olivier-Toledo, Carlos; Viesca-Treviño, Carlos

    2016-01-01

    In this research we focus on the medical evangelist Levi B. Salmans, and The Good Samaritan sanitarium. Doctor Salmans lived in Mexico for about 50 years (1885-1935). During the first part of his stay, he was devoted to found churches and Methodist schools. However, from 1891 he took a turn in his career by founding dispensaries in different towns of Guanajuato to create, in 1899, the private charity association for the sick and infirm The Good Samaritan. His intense, intellectual, and practical work led him to create health journals, to train nurses, and to promote physiotherapies in accordance with the science advances of that time. By itself, this research shows that the history of medicine in Mexico still has long way to go and that Protestant communities, in favor of modernity and scientific knowledge, took a big part in shaping the history of this discipline in Mexico.

  16. Sidelobe reduction of Barker codes, part 7.1C

    NASA Technical Reports Server (NTRS)

    Green, J. L.

    1984-01-01

    Barker codes can be realized as simple digital preprocessors, or with the use of a delay line, can be realized as an analogue device. Assuming the process observed has an autocorrelation time that is long compared to the code length, a gain in signal to noise, G = N where N is the number of elements in the code, may be realized. Typically Barker codes are implemented by shifting the phase of the transmitted signal by 0 or 180 degrees according to the code pattern. A typical detection scheme is shown where the output of the radar receiver is delayed by an analogue delay line or a shift register. The signal in each element of the delay line or shift register is continuously multiplied by the code and all elements are summed. A principal disadvantage was the sidelobe response. In the case of MST or ST radar echoes where there is a dynamic range as large as 60 dB, these unwanted sidelobes cause an increase in the apparent width of atmospheric layers, or some narrow layer to appear at several altitudes. The sidelobes of a Barker code may be reduced by tapering the response of the decoder. Optimum tapers, are shown. It is found that the sidelobe response is greatly reduced with very little loss in G.

  17. Preliminary Research Employing the Watson-Barker Listening Test: A Validation of the Instrument.

    ERIC Educational Resources Information Center

    Roberts, Charles V.

    A study was conducted to further validate the "Watson-Barker Listening Test." The subjects, 120 students enrolled in basic speech courses, completed the Receiver Apprehension Test (RAT) and the Watson-Barker Listening Test: Form A. Statistical analysis of the results revealed a significant correlation between the RAT scores and both the long term…

  18. Take a Walk on the Wild Side, with Folk Artist Jack Barker.

    ERIC Educational Resources Information Center

    Delacruz, Elizabeth Manley

    1999-01-01

    Discusses the life and artwork of Jack Barker who became a folk artist after running a local gas station in Essex, Illinois. Explains that art educators view student interactions with folk artists like Barker as valuable because these artists embody a creative spirit and a thirst for knowledge about materials and processes. (CMK)

  19. Toward an Instructional Philosophy: "A Theoretical Framework for Teaching and Training at Salman Bin Abdulaziz University (SAU)"

    ERIC Educational Resources Information Center

    Qandile, Yasine A.; Al-Qasim, Wajeeh Q.

    2014-01-01

    The purpose of this study is to construct a clear instructional philosophy for Salman bin Abdulaziz University as a fundamental basis for teaching and training as well as a theoretical framework for curriculum design and development. The study attempts to answer the main questions about pertaining to the basic structure of contemporary higher…

  20. Barker-coded excitation in ophthalmological ultrasound imaging

    PubMed Central

    Zhou, Sheng; Wang, Xiao-Chun; Yang, Jun; Ji, Jian-Jun; Wang, Yan-Qun

    2014-01-01

    High-frequency ultrasound is an attractive means to obtain fine-resolution images of biological tissues for ophthalmologic imaging. To solve the tradeoff between axial resolution and detection depth, existing in the conventional single-pulse excitation, this study develops a new method which uses 13-bit Barker-coded excitation and a mismatched filter for high-frequency ophthalmologic imaging. A novel imaging platform has been designed after trying out various encoding methods. The simulation and experiment result show that the mismatched filter can achieve a much higher out signal main to side lobe which is 9.7 times of the matched one. The coded excitation method has significant advantages over the single-pulse excitation system in terms of a lower MI, a higher resolution, and a deeper detection depth, which improve the quality of ophthalmic tissue imaging. Therefore, this method has great values in scientific application and medical market. PMID:25356093

  1. An SNR improvement of passive SAW tags with 5-bit Barker code sequence

    NASA Astrophysics Data System (ADS)

    Bae, Hyunchul; Kim, Jaekwon; Burm, Jinwook

    2012-07-01

    Passive surface acoustic wave (SAW) tags require a large signal-to-noise ratio (SNR) in order to increase the interrogation range. For the purpose of achieving high SNR for radio frequency identification (RFID) communication systems, Barker codes, a binary phase shift keying (BPSK) modulation technique, have been adopted in this study. Passive SAW RFID tags were designed with 5-bit Barker code sequences to generate BPSK modulated signals. Through the SNR analysis, the improvements in SNR were about 11 dB using Barker codes along with a correlator, which can be further improved by optimisation in the correlator.

  2. Barker's Behavior Setting Theory: A Useful Conceptual Framework for Research on Educational Administration.

    ERIC Educational Resources Information Center

    Eklund, S. J.; Scott, M. M.

    1985-01-01

    Research in educational administration needs a coherent empirical base for a comprehensive, ecologically valid theory of administration. This paper describes Roger Barker's Behavior Setting Theory and promotes it as a broad-based conceptual framework for research on educational administration. (Author/TE)

  3. Barker's Ecology of Disadvantage and Educational Equity: Issues of Redistribution and Recognition

    ERIC Educational Resources Information Center

    Raffo, Carlo

    2011-01-01

    As Barker notes, the link between disadvantage and poor educational attainments is an enduring one. Educational policy over the last 40 years or so has tended to respond to educational inequality in predominately one of two ways--attempts to raise standards across the system as a whole and attempts to redistribute resources to families, schools…

  4. A New Way of Thinking about Technology: An Interview with Futurists Joel Barker and Scott Erickson

    ERIC Educational Resources Information Center

    Morrison, James L.; Barker, Joel; Erickson, Scott

    2006-01-01

    Editor-in-chief James Morrison interviews Joel Barker and Scott Erickson, co-authors of the book "Five Regions of the Future: A New Way to Think about Technology". In their book, the authors propose an ecological model that classifies technology according to different clusters or regions, each of which entails its own perspective of technology and…

  5. Time multiplexing super resolution using a 2D Barker-based array

    NASA Astrophysics Data System (ADS)

    Ilovitsh, Asaf; Ilovitsh, Tali; Preter, Eyal; Levanon, Nadav; Zalevsky, Zeev

    2016-03-01

    We propose the use of a two dimensional Barker-based array in order to improve the performance of the standard time multiplexing super resolution system. The Barker-based array is a 2D generalization of the standard 1D Barker code. It enables achieving a two dimensional super resolution image using only one dimensional scan, by exploiting its unique auto correlation property. A sequence of low resolution images are captured at different lateral positions of the array, and are decoded properly using the same array. In addition, we present the use of a mismatched array for the decoding process. The cross correlation between the Barker-based array and the mismatched array has a perfect peak to sidelobes ratio, making it ideal for the super resolution process. Also, we propose the projection of this array onto the object using a phase-only spatial light modulator. Projecting the array eliminates the need for printing it, mechanically shifting it, and having a direct contact with the object, which is not feasible in many imaging applications. The proposed method is presented analytically, demonstrated via numerical simulation, and validated by laboratory experiments.

  6. David Barker, Buruli ulcer and the epidemiology of a neglected tropical disease.

    PubMed

    Phillips, D I W

    2015-10-01

    In 1969, David Barker, his wife and four children moved to Uganda to work at Makerere Medical School in the capital Kampala. During the 1960s, Makerere had become a research and teaching centre with an international reputation based on the work of Trowell, Burkitt, Hutt and many others who had pioneered studies explaining the disease patterns in the West Nile area on the basis of the local climate, nutrition and lifestyle. David Barker was funded by the Medical Research Council to carry out research on a poorly understood disease, Buruli ulcer, joining Scottish surgeon Wilson Carswell, who was later to achieve fame as the role model for Dr Garrigan in Giles Foden's novel The Last King of Scotland.

  7. A binary sequence of period 60 with better autocorrelation properties than the Barker sequence of period 13

    NASA Technical Reports Server (NTRS)

    Watkins, J.; Loftsson, J.; Tyler, S.

    1985-01-01

    A binary sequence of period 60 has been discovered which in some respects has better autocorrelation properties than the Barker sequence of period 13. When both sequences are processed using appropriate sidelobe-eliminating mismatched filters, the Barker sequence's main lobe is reduced by a factor of 1.040 or 0.17 dB, while the new sequence's main lobe is reduced by a factor of only 1.035 or 0.15 dB. This sequence is the first counterexample known to the authors of the hypothesis that the autocorrelation properties of all sequences of periods greater than 13 are inferior to those of the Barker period-13 sequences. Sequences of this type are very useful in radar and deep space communications, especially in situations where there is an adverse signal to noise ratio.

  8. On the path integral representation of the Wigner function and the Barker-Murray ansatz

    NASA Astrophysics Data System (ADS)

    Sels, Dries; Brosens, Fons; Magnus, Wim

    2012-01-01

    The propagator of the Wigner function is constructed from the Wigner-Liouville equation as a phase space path integral over a new effective Lagrangian. In contrast to a paper by Barker and Murray (1983) [1], we show that the path integral can in general not be written as a linear superposition of classical phase space trajectories over a family of non-local forces. Instead, we adopt a saddle point expansion to show that the semiclassical Wigner function is a linear superposition of classical solutions for a different set of non-local time dependent forces. As shown by a simple example the specific form of the path integral makes the formulation ideal for Monte Carlo simulation.

  9. The Eco-Behavioral Approach to Surveys and Social Accounts for Rural Communities: Exploratory Analyses and Interpretations of Roger G. Barker's Microdata from the Behavior Setting Survey of Midwest, Kansas in 1963-64.

    ERIC Educational Resources Information Center

    Fox, Karl A.

    The concept of behavior settings--the environments shaping individual behavior--was originated by Roger Barker in 1950 in connection with his community surveys in a small Kansas town, code-named Midwest. This book seeks to provide rural social scientists with an understanding of Barker's eco-behavioral approach and proposed adaptations of it to…

  10. Assessing the Watson-Barker Listening Test (WBLT)-Form C in Measuring Listening Comprehension of Post-Secondary Hispanic-American Students

    ERIC Educational Resources Information Center

    Worthington, Debra L.; Keaton, Shaughan; Cook, John; Fitch-Hauser, Margaret; Powers, William G.

    2014-01-01

    The Watson-Barker Listening Test (WBLT) is one of the most popular measures of listening comprehension. However, participants in studies utilizing this scale have been almost exclusively Anglo-American. At the same time, previous research questions the psychometric properties of the test. This study addressed both of these issues by testing the…

  11. Holocene palaeoclimate and sea level fluctuation recorded from the coastal Barker Swamp, Rottnest Island, south-western Western Australia

    NASA Astrophysics Data System (ADS)

    Gouramanis, C.; Dodson, J.; Wilkins, D.; De Deckker, P.; Chase, B. M.

    2012-10-01

    The Holocene palaeoclimatic history of south-western Western Australia (SWWA) has received little attention compared to south-eastern Australia, and this has resulted in conflicting views over the impact of climate variability in the region. We present here a well-dated, high-resolution record from two overlapping sediment cores obtained from the centre of Barker Swamp, Rottnest Island, offshore Perth. The records span the last 8.7 ka, with the main lacustrine phase occurring after 7.4 ka. This site preserves both pollen and several ostracod taxa. The pollen record suggests a long-term shift from the early-mid Holocene to the late Holocene to drier conditions with less shrubland and more low-ground cover and less fire activity. A salinity transfer function was developed from ostracod faunal assemblage data and trace metal ratios (Mg/Ca, Sr/Ca and Na/Ca) and stable isotopes (δ18O and δ13C) analysed on selected ostracod valves. These provide a detailed history of evaporation/precipitation (E/P) differences that clearly shows that the SWWA region was subjected to significant climatic shifts over the last 7.4 ka, with a broad shift towards increased aridity after 5 ka. The swamp ranged from fresh to saline as recorded in the ostracod valve chemistry and the independently-derived salinity transfer function. The ostracod record also indicates that a sea-level highstand occurred between ca. 4.5 and 4.3 ka, with probable step-wise increases at 6.75, 6.2, and 5.6 ka, with the last vestiges of salt water intrusion at ca. 1 ka. After about 2.3 ka, the fresh, groundwater lens that underlies the western portion of the island intersected the swamp depression, influencing the hydrology of the swamp. The broad climatic changes recorded in Barker Swamp are also compared with data from southern South Africa, and it is suggested that the Southern Annular Mode appears to have been the dominant driver in the climate of these regions and that the Indian Ocean Dipole is of little

  12. The Stories We Hear, the Stories We Tell What Can the Life of Jane Barker (1652-1732) Tell Us about Women's Leadership in Higher Education in the Twenty-First Century?

    ERIC Educational Resources Information Center

    Wilson, Carol Shiner

    2009-01-01

    Jane Barker--poet, novelist, farm manager, student and practitioner of medical arts--was not allowed to attend university because she was a woman. Yet she was Oxford-educated in the most modern of medical theories of her time. By the end of her life, unmarried by choice, Barker was writing for pay under her own name in an emerging genre--the…

  13. Application of wavelet filtering and Barker-coded pulse compression hybrid method to air-coupled ultrasonic testing

    NASA Astrophysics Data System (ADS)

    Zhou, Zhenggan; Ma, Baoquan; Jiang, Jingtao; Yu, Guang; Liu, Kui; Zhang, Dongmei; Liu, Weiping

    2014-10-01

    Air-coupled ultrasonic testing (ACUT) technique has been viewed as a viable solution in defect detection of advanced composites used in aerospace and aviation industries. However, the giant mismatch of acoustic impedance in air-solid interface makes the transmission efficiency of ultrasound low, and leads to poor signal-to-noise (SNR) ratio of received signal. The utilisation of signal-processing techniques in non-destructive testing is highly appreciated. This paper presents a wavelet filtering and phase-coded pulse compression hybrid method to improve the SNR and output power of received signal. The wavelet transform is utilised to filter insignificant components from noisy ultrasonic signal, and pulse compression process is used to improve the power of correlated signal based on cross-correction algorithm. For the purpose of reasonable parameter selection, different families of wavelets (Daubechies, Symlet and Coiflet) and decomposition level in discrete wavelet transform are analysed, different Barker codes (5-13 bits) are also analysed to acquire higher main-to-side lobe ratio. The performance of the hybrid method was verified in a honeycomb composite sample. Experimental results demonstrated that the proposed method is very efficient in improving the SNR and signal strength. The applicability of the proposed method seems to be a very promising tool to evaluate the integrity of high ultrasound attenuation composite materials using the ACUT.

  14. How To Use Barker's Paradigm Concepts To Help Solve Major Higher Education Problems and Help Create a Vital Future for Institutional Research and Planning. AIR 1993 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Meredith, Mark

    This paper introduces, as a new, relevant, technique for use in institutional research and planning, the concept of paradigms as presented by J. A. Barker. The paper uses as examples of these concepts analysis of two major problems, frequently found in higher education and institutional research and planning. These examples illustrate how outsider…

  15. Fluid-fluid and fluid-solid transitions in the Kern-Frenkel model from Barker-Henderson thermodynamic perturbation theory

    NASA Astrophysics Data System (ADS)

    Gögelein, Christoph; Romano, Flavio; Sciortino, Francesco; Giacometti, Achille

    2012-03-01

    We study the Kern-Frenkel model for patchy colloids using Barker-Henderson second-order thermodynamic perturbation theory. The model describes a fluid where hard sphere particles are decorated with one patch, so that they interact via a square-well potential if they are sufficiently close one another, and if patches on each particle are properly aligned. Both the gas-liquid and fluid-solid phase coexistences are computed and contrasted against corresponding Monte Carlo simulations results. We find that the perturbation theory describes rather accurately numerical simulations all the way from a fully covered square-well potential down to the Janus limit (half coverage). In the region where numerical data are not available (from Janus to hard-spheres), the method provides estimates of the location of the critical lines that could serve as a guideline for further efficient numerical work at these low coverages. A comparison with other techniques, such as integral equation theory, highlights the important aspect of this methodology in the present context.

  16. Zachary D. Barker: Final DHS HS-STEM Report

    SciTech Connect

    Barker, Z D

    2008-08-14

    Working at Lawrence Livermore National Laboratory (LLNL) this summer has provided a very unique and special experience for me. I feel that the research opportunities given to me have allowed me to significantly benefit my research group, the laboratory, the Department of Homeland Security, and the Department of Energy. The researchers in the Single Particle Aerosol Mass Spectrometry (SPAMS) group were very welcoming and clearly wanted me to get the most out of my time in Livermore. I feel that my research partner, Veena Venkatachalam of MIT, and I have been extremely productive in meeting our research goals throughout this summer, and have learned much about working in research at a national laboratory such as Lawrence Livermore. I have learned much about the technical aspects of research while working at LLNL, however I have also gained important experience and insight into how research groups at national laboratories function. I believe that this internship has given me valuable knowledge and experience which will certainly help my transition to graduate study and a career in engineering. My work with Veena Venkatachalam in the SPAMS group this summer has focused on two major projects. Initially, we were tasked with an analysis of data collected by the group this past spring in a large public environment. The SPAMS instrument was deployed for over two months, collecting information on many of the ambient air particles circulating through the area. Our analysis of the particle data collected during this deployment concerned several aspects, including finding groups, or clusters, of particles that seemed to appear more during certain times of day, analyzing the mass spectral data of clusters and comparing them with mass spectral data of known substances, and comparing the real-time detection capability of the SPAMS instrument with that of a commercially available biological detection instrument. This analysis was performed in support of a group report to the Department of Homeland Security on the results of the deployment. The analysis of the deployment data revealed some interesting applications of the SPAMS instrument to homeland security situations. Using software developed in-house by SPAMS group member Dr. Paul Steele, Veena and I were able to cluster a subset of data over a certain timeframe (ranging from a single hour to an entire week). The software used makes clusters based on the mass spectral characteristics of the each particle in the data set, as well as other parameters. By looking more closely at the characteristics of individual clusters, including the mass spectra, conclusions could be made about what these particles are. This was achieved partially through examination and discussion of the mass spectral data with the members of the SPAMS group, as well as through comparison with known mass spectra collected from substances tested in the laboratory. In many cases, broad conclusions could be drawn about the identity of a cluster of particles.

  17. Historical note: Snow, Empson and the Barkers of Bath.

    PubMed

    Zuck, D

    2001-03-01

    The identity of the artist who painted the well-known portrait of John Snow has been established. It has been discovered that the painting was exhibited at the Royal Academy of Arts, London in 1847. PMID:11251428

  18. How Bob Barker Would (Probably) Teach Discrete Mathematics

    ERIC Educational Resources Information Center

    Urness, Timothy

    2010-01-01

    This article proposes a discrete mathematics course in which games from "The Price Is Right" are used to engage students in a deeper, practical study of discrete mathematics. The games themselves are not the focus of the course; rather, the mathematical principles of the games give motivation for the concepts being taught. The game examples are…

  19. Kodamaea Y. Yamada, T. Suzuki, Matsuda & Mikata emend. Rosa, Lachance, Starmer, Barker, Bowles & Schlag-Edler (1999)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Kodamaea and is to be published in The Yeasts, A Taxonomic Study, 5th edition. The genus Kodamaea has five assigned species and all are associated with wood boring insects. Many of the species appear worldwide in distribution. One of the species, K...

  20. Effects on water quality due to flood-water detention by Barker and Addicks Reservoirs, Houston, Texas

    USGS Publications Warehouse

    Liscum, Fred; Goss, R.L.; Paul, E.M.

    1987-01-01

    The third approach was a comparison at each site of the mean, maximum, and minimum values computed for seven constituents that did not correlate with discharge. These constituents or properties of water were temperature, pH, dissolved oxygen, dissolved oxygen percent saturation, total-coliform bacteria, fecal-conform bacteria, and fecal-streptococci bacteria. The only consistent water-quality changes observed were with the three bacteria groups, which were decreased by flood-water detention.

  1. An Introduction to Student Quality Circle at College of Business Administration, Salman Bin Abdulaziz University, Al Kharj, Kingdom of Saudi Arabia--An Empirical Study

    ERIC Educational Resources Information Center

    Faridi, Mohammad Rishad; Al Kahtani, Nasser Saad; Alam, Teg; Malki, Said

    2014-01-01

    Catch 'em young for imparting hands-on rigorous academic training. This is what has been relentlessly pursued while dealing with the undergraduate students of business management who are to be thoroughly exposed to the whole gamut of quality work life. Whether they opt for corporate career or pursue masters or choose be an entrepreneur, their…

  2. Theoretical and Practical Approaches to Teaching Listening: Using the Watson-Barker Listening Test To Validate Levels of Learning in the Classroom.

    ERIC Educational Resources Information Center

    Watt, Willis M.

    A study investigated whether listening effectiveness could be improved by completing a college listening class. Volunteer subjects, 14 males and 14 females enrolled in a 3-hour, 16-week college listening course for undergraduate or graduate students at a medium-sized midwestern university, were given the video version of the Watson-Barker…

  3. Alternative computational protocols for supercharging protein surfaces for reversible unfolding and retention of stability.

    PubMed

    Der, Bryan S; Kluwe, Christien; Miklos, Aleksandr E; Jacak, Ron; Lyskov, Sergey; Gray, Jeffrey J; Georgiou, George; Ellington, Andrew D; Kuhlman, Brian

    2013-01-01

    Reengineering protein surfaces to exhibit high net charge, referred to as "supercharging", can improve reversibility of unfolding by preventing aggregation of partially unfolded states. Incorporation of charged side chains should be optimized while considering structural and energetic consequences, as numerous mutations and accumulation of like-charges can also destabilize the native state. A previously demonstrated approach deterministically mutates flexible polar residues (amino acids DERKNQ) with the fewest average neighboring atoms per side chain atom (AvNAPSA). Our approach uses Rosetta-based energy calculations to choose the surface mutations. Both protocols are available for use through the ROSIE web server. The automated Rosetta and AvNAPSA approaches for supercharging choose dissimilar mutations, raising an interesting division in surface charging strategy. Rosetta-supercharged variants of GFP (RscG) ranging from -11 to -61 and +7 to +58 were experimentally tested, and for comparison, we re-tested the previously developed AvNAPSA-supercharged variants of GFP (AscG) with +36 and -30 net charge. Mid-charge variants demonstrated ∼3-fold improvement in refolding with retention of stability. However, as we pushed to higher net charges, expression and soluble yield decreased, indicating that net charge or mutational load may be limiting factors. Interestingly, the two different approaches resulted in GFP variants with similar refolding properties. Our results show that there are multiple sets of residues that can be mutated to successfully supercharge a protein, and combining alternative supercharge protocols with experimental testing can be an effective approach for charge-based improvement to refolding. PMID:23741319

  4. 75 FR 28769 - Safety Zone; Osage River, Mile 016.8 to 017.2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-24

    ... Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public meeting. But you may... questions on this proposed rule, call or e-mail Lieutenant Commander (LCDR) Matthew Barker, Sector Upper Mississippi River Response Department at telephone 314-269-2540, e-mail Matthew.P.Barker@uscg.mil . If...

  5. "No Change There Then!" (? ): The Onward March of School Markets and Competition

    ERIC Educational Resources Information Center

    Lupton, Ruth

    2011-01-01

    This article reviews Bernard Barker's claims that "the pendulum is swinging", in relation to school markets and competition. Barker's arguments are complex in this regard. He rejects markets and competition as a means of improving outcomes and equity, but supports some of the system features that are often associated with marketisation, such as…

  6. A Policy Sociology Reflection on School Reform in England: From the "Third Way" to the "Big Society"

    ERIC Educational Resources Information Center

    Lingard, Bob; Sellar, Sam

    2012-01-01

    This article presents a policy sociology reflection on Bernard Barker's book, "The Pendulum Swings: Transforming School Reform". The book represents Barker's attempt to intervene in education policy during the lead-up to the 2010 UK general election and is framed by what he imagined might be possible under a new Conservative government. Barker…

  7. New and little-known pygmy grasshoppers (Orthoptera: Tetrigidae) from Thailand.

    PubMed

    Storozhenko, Sergey Yu; Dawwrueng, Pattarawich

    2015-01-01

    An annotated list of 39 species in 25 genera and seven subfamilies of the pygmy grasshoppers (Orthoptera: Tetrididae) from Thailand is given; from these 18 species are recorded from this country for the first time. Five new species are described: Cotysoides gaponi sp. nov. (subfamily Metrodorinae), Eucriotettix anisyutkini sp. nov., Gavialidium bufocrocodil sp. nov., Scelimena bellula sp. nov. (subfamily Scelimeninae) and Phaesticus uvarovi sp. nov. (subfamily Discotettiginae). One species is transferred from Scelimena to Amphibotettix and a new combination is proposed: Scelimena hafizhaii Mahmmod, Idris et Salman, 2007 = Amphibotettix hafizhaii (Mahmmod, Idris et Salman, 2007), comb. nov. The previously unknown male of Falconius tschernovi Storozhenko, 2014 is described. PMID:26701451

  8. Can Khan Move the Bell Curve to the Right?

    ERIC Educational Resources Information Center

    Kronholz, June

    2012-01-01

    More than 1 million people have watched the online video in which Salman Khan--a charming MIT math whiz, Harvard Business School graduate, and former Boston hedge-fund analyst--explains how he began tutoring his cousins in math by posting short lessons for them on YouTube. Other people began watching the lessons and sending Khan adulatory notes.…

  9. Payload specialist Al-Saud siting in middeck area

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialist Sultan Salman Abdelazize Al-Saud seated in a posture common to weightlessness as he logs notes in Discovery's middeck area. He has headphones on connected to a portable tape recorder. Behind him on the middeck lockers is a sign which reads 'Welcome to Riyadh'. On the other wall, a sleep restraint is attached to the lockers.

  10. Communicating with Parents of Children with Special Needs in Saudi Arabia: Parents' and Teachers' Perceptions of Using Email for Regular and Ongoing Communication

    ERIC Educational Resources Information Center

    Dubis, Snaa; Bernadowski, Carianne

    2015-01-01

    The purpose of this study, by Snaa Dubis from Salman Bin Abdu Aziz University, Saudi Arabia, and Robert Morris University, USA, and Carianne Bernadowski from Robert Morris University, was to investigate parents' and special education teachers' perceptions of using email as a component of parental involvement in the academic and/or behavioural…

  11. Payload specialists Baudry and Al-Saud in the middeck

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The two payload specialists for the STS 51-G flight share a middeck scene on Discovery. Sultan Salman Abdelazize Al-Saud (left) is in the midst of a meal while Patrick Baudry conducts a phase of the French Postural Experiment (FPE) on himself. Sleep restraints are in the background.

  12. Payload specialists Baudry and Al-Saud conduct Postural experiment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialists Patrick Baudry (left) and Sultan Salman Abdelazize Al-Saud team up to conduct a French Postural Experement (FPE) on the middeck of the Space shuttle Discovery during the STS 51-G flight. Behind them on the middeck walls are two sleep restraints.

  13. STS 51-G simulate meal session on orbiter's middeck

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Three members of the STS 51-G crew simulate a meal session on the orbiter's middeck during training in the crew compartment trainer at JSC's shuttle mockup and integration facility. Pictured (l.-r.) are Sultan Salman Abdelzize Al-Saud, John N. Fabian and Patrick Baudry. Fabian is a mission specialist and the other two men are payload specialists.

  14. Payload specialist Sultan Abdelazize Al-Saud conducts Postural experiment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialist Sultan Salman Abdelazize Al-Saud assists in conducting a French Postural Experement (FPE) on the middeck of the Space shuttle Discovery during the STS 51-G flight. Behind him on the middeck walls are two sleep restraints. At the bottom of the frame, foot restraints are visible.

  15. STS 51-G crew photo on the flight deck

    NASA Technical Reports Server (NTRS)

    1985-01-01

    STS 51-G crew photo on the flight deck. Left to right in the front are John O. Creighton, Shannon W. Lucid, Daniel C. Brandenstein; and in the back row are Sultan Salman Abdelazize Al-Saud, Steven R. Nagel, John N. Fabian and Patrick Baudry.

  16. Portrait of STS 51-G Payload Specialists

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Portrait of STS 51-G Payload specialists. Left to right are Patrick Baudry, for the Centre National d'Etudes Spatiales of France; Abdulmohsen Hamad Al-Bassan, backup payload specialist to Sultan Salman Abdelazize Al-Saud of Saudi Arabia. They are standing in front of a small table containing a model of the Space Shuttle.

  17. Portrait of STS 51-G crew

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Portrait of STS 51-G crew. Kneeling in front are Astronauts Daniel C. Brandenstein (left) and John O. Creighton, commander and pilot, respectively. Astronauts Shannon W. Lucid, Steven R. Nagel, and John M. Fabian, mission specialist (l.-r.) joing Payload specialists Sultan Salman Abdelazize Al-Saud (second right) and Patrick Baudry on the back row.

  18. Toward a One-World Schoolhouse: Interview with Sal Khan

    ERIC Educational Resources Information Center

    Pinkus, Ari

    2015-01-01

    Ten years ago, Salman Khan, with three degrees from MIT and an MBA from Harvard, agreed to help tutor his cousin Nadia, who was struggling in math. Using Yahoo's Doodle notepad, Khan offered Nadia a sequence of mini lessons designed to scaffold her learning. Over time, other friends and relatives heard about Khan's success and asked for similar…

  19. Can Khan Move the Bell Curve to the Right?

    ERIC Educational Resources Information Center

    Kronholz, June

    2012-01-01

    This article features Khan Academy which offers an online math program and short video lectures embedded in the "module", or math concept, that fit students' goals. By now, more than 1 million people have watched the online video in which Salman Khan--a charming MIT math whiz, Harvard Business School graduate, and former Boston hedge-fund…

  20. Commentary: The Khan Academy and the Day-Night Flipped Classroom

    ERIC Educational Resources Information Center

    Parslow, Graham R.

    2012-01-01

    Teaching by night and reflecting on a subject by day is the way that Salman Khan sees education evolving in the age of online lectures. Khan believes he is onto something in what he styles the "flipped classroom." In Khan's view, there is no need for students to be divided into grades by age. Instead, they should learn at their own pace, moving on…

  1. Schools "Flip" for Lesson Model Promoted by Khan Academy

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2011-01-01

    The author reports on a "flip model" of instruction that has gotten national media attention lately, thanks to its promotion by Khan Academy, the high-profile nonprofit online-tutoring library created by Salman A. Khan, a Massachusetts Institute of Technology graduate who was looking for a way to help his young relatives with their homework. The…

  2. Flip or Flop: Are Math Teachers Using Khan Academy as Envisioned by Sal Khan?

    ERIC Educational Resources Information Center

    Cargile, Lori A.; Harkness, Shelly Sheats

    2014-01-01

    Khan Academy (KA) is a free web-based intelligent tutor, which has been featured in countless media outlets for its potential to change mathematics instruction. The founder and executive director, Salman Khan, recommends that KA be used to personalize instruction, freeing up class time for engaging high yield activities like student discourse and…

  3. Streaming in English Primary Schools

    ERIC Educational Resources Information Center

    Acland, H.

    1973-01-01

    This paper seeks to extend our knowledge of ability grouping through the reanalysis of two sets of survey data, the Plowden survey (Peaker, 1967) and the NFER streaming survey (Barker Lunn, 1970). (Editor)

  4. Linking Early Environmental Exposures to Adult Diseases

    MedlinePlus

    ... David Barker, for example, put forward the “fetal programming or developmental basis of health and disease” hypothesis, ... mechanisms by which fetal insults lead to altered programming and to disease later in life. RESEARCH FINDINGS ...

  5. Do we need another model for mental health care?

    PubMed

    Noak, J

    In this discussion, James Noak critiques Fletcher and Stevenson's (2001) article 'Launching the Tidal Model in an adult mental health programme'. Responses from the authors and Phil Barker, author of the Tidal Model, follow.

  6. 76 FR 19772 - Environmental Impacts Statements; Notice of Availability

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-08

    .... Revision to FR Notice Published 02/18/2011: Extending Comment Period from 04/04/2011 to 05/04/2011. Dated..., Contact: Scott Barker 208-735-2072. EIS No. 20110101, Final EIS, USFS, CO, Big Moose Vegetation...

  7. 50. Trash strainer and sluice gate at top of castiron ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. Trash strainer and sluice gate at top of cast-iron pipe penstock leading to Barker turbine. HAER PR, 6-MAGU, 1D-2 - Hacienda Buena Vista, PR Route 10 (Ponce to Arecibo), Magueyes, Ponce Municipio, PR

  8. 75 FR 69433 - City of Boulder, CO; Notice of Availability of Environmental Assessment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-12

    ... Regulatory Commission's (Commission) regulations, 18 CFR part 380 (Order No. 486, 52 FR 47879), the Office of...; (5) the valve house; (6) the concrete Barker gravity pipeline; (7) the Kossler Reservoir,...

  9. STS 51-G crewmembers depart KSC's operations and checkout building

    NASA Technical Reports Server (NTRS)

    1985-01-01

    STS 51-G crewmembers depart the Kennedy Space Center's operations and checkout building on their way to the launch pad for the launch of the Discovery. Leading the seven are Daniel C. Brandenstein, commander; and John O. Creighton, pilot. Following are Payload specialist Sultan Salman Abdelazize Al-Saud; John M. Fabian, mission specialist; Patrick Baudry, payload specialist; Shannon Lucid and Steven R. Nagel, mission specialists.

  10. Crew of the STS 51-G Discovery egress the orbiter in California

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The crew of the STS 51-G Discovery egress the orbiter in California at the end of the mission. Astronaut Danel C. Brandenstein, crew commander, shakes hands with George W.S. Abbey, Director of Flight Crew Operations at JSC. Behind Brandenstein are (bottom to top) John O. Creighton, John M. Fabian, Shannon W. Lucid, Sultan Salman Abdelazize Al-Saud, Patrick Baudry and Steven R. Nagel.

  11. An Adult Protective Services' view of collaboration with Mental Health Services.

    PubMed

    Teaster, Pamela B; Stansbury, Kim L; Nerenberg, Lisa; Stanis, Patricia

    2009-10-01

    Mental Health Services (MHS) meet mental health needs of older adults through active, outpatient, community-based care. Adult Protective Services (APS) are involved with needs of older adults who have mental disability and mental illness. Adult Protective Services and MHS staff may to work together when they respond to the needs of victims and adults at risk for abuse, neglect, self-neglect, and exploitation. The purpose of this study was to understand effective APS-MHS collaborations (e.g., leadership, organizational culture, administration, and resources in predicting success). A survey that was sent to members of the National Adult Protective Services Association (NAPSA) revealed that both APS and MHS have strong commitments to protecting clients' rights and autonomy, but there appear to be differences between the two with regard to implementation, apparent in cases involving clients with diminished mental capacity who are at imminent risk, but who refuse help. Strengths of APS-MHS collaborations included improved communication and better service for at-risk clients.

  12. A Comparative Examination and Analysis of Three Listening Tests.

    ERIC Educational Resources Information Center

    Rubin, Rebecca B.; Roberts, Charles V.

    1987-01-01

    Examines the conceptual and methodological similarities and differences of three listening measures--the Watson-Barker Listening Test, Kentucky Comprehensive Listening Test, and the Communication Competency Assessment Instrument. Provides information on the concepts being assessed in each and illuminates major methodological issues for listening…

  13. Ecological Theory and Method for Behavioral Assessment.

    ERIC Educational Resources Information Center

    Carlson, Cindy I.; And Others

    1980-01-01

    The theoretical perspective and naturalistic methods of ecological psychology developed by Roger Barker are described. Ecological assessment implies examining (1) naturally occurring behavior; (2) environment immediately surrounding behavior; and (3) the individual-environment link. The specimen record, chronolog, and behavior-setting survey are…

  14. The Question of Validity and Application: How Do We Know How Well We Are Listening.

    ERIC Educational Resources Information Center

    Roberts, Charles V.

    To test the validity of the Watson-Barker Listening Test (WBLT), a study was conducted based on the hypothesis that there is a curvilinear relationship between receiver apprehension and listening ability. Subjects, 120 undergraduate speech students, completed the Receiver Apprehension Test (RAT) and the WBLT. Analysis of the data revealed a…

  15. Theories of Person-Environment Interaction: Implications for the College Student. Monograph 10.

    ERIC Educational Resources Information Center

    Walsh, W. Bruce

    The basic objective of this monograph is to present and review a few selected theories of person-environment interaction which have stimulated meaningful research. Five theoretical viewpoints are included: Barker's theory of behavior settings, the subcultural approach, Holland's theory of personality types and model environments, Stern's need x…

  16. Some Theories of Person/Environment Interaction

    ERIC Educational Resources Information Center

    Walsh, W. Bruce

    1975-01-01

    This article is a review of five selected theories of person/environment interaction. The five theoretical viewpoints reviewed are Barker's theory of behavior settings, the subculture approach, Holland's theory of personality types and model environments, Stern's need X press=culture theory, and Pervin's transactional approach. (Author)

  17. Profiles of Children's Behavior in Various Lessons.

    ERIC Educational Resources Information Center

    Day, David E.; Libertini, Gail E.

    This study investigated the behavioral responses of eight children to five alternate lesson types. Barker's assertion of the coercive nature of setting was examined. Questions addressed were: (1) Do children having the same or similar lessons behave asimilarly or differently? (2) Do children change their patterns of behavior as they move from one…

  18. Word Order in Klamath.

    ERIC Educational Resources Information Center

    Sundberg, Karen

    The word order in Klamath, a Penutian language of southern Oregon, has been described as almost completely "free". The language is examined in terms of the effect of the relative topicality of arguments on their position preceding or following the verb. The database used for this study consisted of seven Klamath texts from Barker (1963): five…

  19. Transformational Leadership and Organizational Commitment: A Study of UNC System Business School Department Chairs

    ERIC Educational Resources Information Center

    Luton, Bill

    2010-01-01

    Ample evidence is available citing a positive relationship between transformational leadership and organizational commitment (Boerner et al., 2007; Bono & Judge, 2003; Bycio, Hackett, & Allen, 1995; Chen, 2004; Emery & Barker, 2007; Walumbwa, Orwa, Wang, & Lawler, 2005). The majority of research on leadership in higher education, however, is based…

  20. Conflicting Perceptions of the Status of Field Biology and Identification Skills in UK Education

    ERIC Educational Resources Information Center

    Goulder, Raymond; Scott, Graham W.

    2016-01-01

    Reviews of the state of biology fieldwork in UK schools and universities at the beginning of the twenty-first century (Barker, Slingsby, and Tilling 2002; Smith 2004) were not entirely pessimistic; rather they suggested ways forward that might lead to an increase in fieldwork. Whether their hopes have been realised has, perhaps, been revealed by…

  1. Between "Bastard" and "Wicked" Leadership? School Leadership and the Emerging Policies of the UK Coalition Government

    ERIC Educational Resources Information Center

    Wright, Nigel

    2011-01-01

    Barker argues that in England under New Labour, school leaders and teachers have been "bastardised" and suggests that the situation in 2010, with a general election afforded an opportunity in education policy for the "pendulum to swing". In this article, the key points about "bastard Leadership" are briefly summarised. The article then develops a…

  2. Adding a New Dimension to Algebra

    ERIC Educational Resources Information Center

    Gordon, Sheldon P.

    2013-01-01

    Much of what is taught, especially in college, is designed to support other disciplines. To determine the current mathematical needs of twenty-three partner disciplines, the Mathematical Association of America (MAA) conducted the Curriculum Foundations Project (Ganter and Barker 2004; Ganter and Haver 2011), as discussed in the appendix…

  3. Novel concepts in the developmental origins of adult health and disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The seminal epidemiological observations of David Barker demonstrated that birth weight across the normal range is inversely proportional to the risk for hypertension, cardiovascular disease, and type 2 diabetes in adulthood. Increasing evidence suggests that either low birth weight or accelerated p...

  4. Is Small Really Better? Testing Some Assumptions about High School Size

    ERIC Educational Resources Information Center

    Schneider, Barbara L.; Wyse, Adam E.; Keesler, Venessa

    2007-01-01

    The case for small schools has been made in educational research since the 1960s, when scholars such as Barker and Gump argued that smaller schools provided students with greater opportunities for participation in various extracurricular activities. The value of small schools was further supported in the 1980s by research on public and private…

  5. The Ecological Psychology of the Small Town.

    ERIC Educational Resources Information Center

    Miller, Duane I.

    1989-01-01

    Uses principles of ecological theory to predict architectural needs of a small town. Examines Barker's concept of undermanning which led to six hypotheses regarding small-town behavior and corresponding design recommendations. Concludes that psychology of small-town resident is unique because of special ecological demands placed on the people.…

  6. Mentoring Influence on Socially Responsible Leadership Capacity Based on Institutional Carnegie Classification

    ERIC Educational Resources Information Center

    Gleason, Michael C.

    2012-01-01

    Higher education institutions are being called to provide leaders capable of operating in increasingly complex environments (Astin & Astin, 2000; Daloz Parks, 2005; Longo & Gibson, 2011; Rost & Barker, 2000). As immersion into these complex environments has been found to assist students in developing leadership capacities, mentoring is…

  7. Examining the Implementation of an Innovative Mathematics Curriculum

    ERIC Educational Resources Information Center

    Hansen, Heidi Britte

    2010-01-01

    Reform in mathematics instruction at the college level has been slow to arrive (Dossey, Halvorson, & McCrone, 2008), and many institutions of higher learning still follow the calculus model, while fewer and fewer students need calculus for their chosen areas of study (Ganter & Barker, 2003). Instead, mathematics that is applicable and transferable…

  8. The Reality of Sustaining Community-Based Sport and Physical Activity Programs to Enhance the Development of Underserved Youth: Challenges and Potential Strategies

    ERIC Educational Resources Information Center

    Whitley, Meredith A.; Forneris, Tanya; Barker, Bryce

    2015-01-01

    Many community-based sport and physical activity programs take a positive youth development approach when operating in underserved communities around the world (Forneris, Whitley, & Barker, 2013). However, one of the biggest challenges for these programs is sustainability (Lindsey, 2008). The purpose of this article is to present the 3…

  9. The Five E's: Ethnicity, Education, Economy, Equity, and Environment. Proceedings [of the] Annual Conference of the Global Awareness Society International (Chicago, Illinois, June 1994).

    ERIC Educational Resources Information Center

    Huber, James H., Ed.; And Others

    The 23 conference papers in this proceedings include: (1) "Global Awareness Society International: Retrospectives and Prospectives" (Chang Shub Roh); (2) "Technology Transfer in Developing Countries: The Case of Turkey (1989-1994)" (Huseyin Ates; Asim Sen); (3) "Indigenous People, Environmental Protection and Globalization" (Edward D. Barker); (4)…

  10. Facing Up to Radical Changes in Universities and Colleges. Staff and Educational Development Series.

    ERIC Educational Resources Information Center

    Armstrong, Steve, Ed.; And Others

    This collection of 18 essays focuses on efforts to manage change in higher education, primarily at universities in the United Kingdom. It includes: (1) "Changing Universities: From Evolution to Revolution" (Gail Thompson); (2) "Assessing Attitudes to Electronic Lectures" (Philip Barker); (3) "Teaching and Learning Technology: Shifting the Culture"…

  11. Manliness and Exploration: The Discovery of the North Pole.

    PubMed

    Robinson, Michael

    2015-01-01

    Americans crowded newsstands in early 1910 to read Robert Peary's firsthand account of his expedition to the North Pole. As they read "The Discovery of the North Pole," serialized exclusively in Hampton's Magazine, few knew that this harrowing, hypermasculine tale was really crafted by New York poet Elsa Barker. Barker's authorship of the North Pole story put her at the center of a large community of explorers, writers, patrons, and fans who were taken with Arctic exploration as much for its national symbolism as for its thrilling tales. The fact that Barker was a woman made her ascent into elite expeditionary circles remarkable. Yet this essay argues that it was also representative: women shaped the ideas and practices of manly exploration at home as well as in the field. Peary's dependence upon women writers, patrons, and audiences came at a time when explorers were breaking away from their traditional base of support: male scientific networks that had promoted their expeditions since the 1850s. Despite the "go-it-alone" ideals of their expedition accounts, explorers adopted masculine roles shaped by the world around them: by the growing influence of women writers, readers, and lecture-goers and, simultaneously, by the declining influence of traditional scientific peers and patrons. Barker and Peary's story, then, reveals a new fault line that opened up between scientists and explorers in the late nineteenth century over the issue of manliness, a fault line still largely uncharted in historical scholarship.

  12. Animal Models for Testing the DOHaD Hypothesis

    EPA Science Inventory

    Since the seminal work in human populations by David Barker and colleagues, several species of animals have been used in the laboratory to test the Developmental Origins of Health and Disease (DOHaD) hypothesis. Rats, mice, guinea pigs, sheep, pigs and non-human primates have bee...

  13. PRENATAL EXPOSURE TO LOW DOSE PFOA INDUCES LOW DEVELOPMENTAL BODY WEIGHT FOLLOWED BY ADULT ONSET OBESITY THAT IS BLUNTED IN OVARIECTOMIZED ANIMALS

    EPA Science Inventory

    The Barker hypothesis, or fetal origins of adult disease, proposes that individuals born to mothers who were pregnant during lean times develop a "thrifty" phenotype with a smaller body size and lowered metabolic rates, leading to a propensity for obesity and development of disor...

  14. Censorship of Off-Campus Publications Violates First Amendment Rights.

    ERIC Educational Resources Information Center

    Adams, Julian

    1989-01-01

    Reviews Burch v. Barker, in which the Ninth Circuit Court of Appeals ruled that school administrators' prior review of an alternative or off-campus publication, destined for distribution on the school campus, is in violation of the First Amendment. (MS)

  15. [Papers of the ELF Project].

    ERIC Educational Resources Information Center

    Barker, Philip; And Others

    The five papers in this collection discuss various aspects of the Electronic Learning-Package Factory (ELF) project at the University of Bradford in England. In the first paper, "Adoption of CAL in Higher Education: A Cooperative Approach to Research, Development and Implementation," Philip Barker considers the opportunities for collaborative…

  16. Teaching Web Search Skills: Techniques and Strategies of Top Trainers

    ERIC Educational Resources Information Center

    Notess, Greg R.

    2006-01-01

    Here is a unique and practical reference for anyone who teaches Web searching. Greg Notess shares his own techniques and strategies along with expert tips and advice from a virtual "who's who" of Web search training: Joe Barker, Paul Barron, Phil Bradley, John Ferguson, Alice Fulbright, Ran Hock, Jeff Humphrey, Diane Kovacs, Gary Price, Danny…

  17. 76 FR 7817 - Announcing Draft Federal Information Processing Standard 180-4, Secure Hash Standard, and Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... more flexibility and efficiency in implementing the secure hash algorithms in many computer network... sent to: Chief, Computer Security Division, Information Technology Laboratory, Attention: Comments on... electronically at http://csrc.nist.gov/CryptoToolkit/ . FOR FURTHER INFORMATION CONTACT: Elaine Barker,...

  18. The Market for Vocational Education and Training.

    ERIC Educational Resources Information Center

    Robinson, Chris, Ed.; Kenyon, Richard, Ed.

    These 43 conference papers on vocational education and training (VET) markets are grouped under three broad themes describing them. Sixteen papers deal with the VET product and providers: "The VET Market" (Kemp); "Market Frameworks in VET" (FitzGerald); "The New Zealand Market Approach" (Barker); "An Economic Primer to Government's Role in VET"…

  19. The Acquisition of Case in Spanish Pronominal Object Clitics in English-Speaking College-Level L2 Learners

    ERIC Educational Resources Information Center

    Olsen, Michael Kevin

    2013-01-01

    The second language acquisition (SLA) of Spanish pronominal object clitics (POCs) has been a topic of research with regards to clitic placement (Houston, 1997; Lee, 1987; LoCoco, 1987; VanPatten, 1984; and VanPatten & Houston 1998), acquiring specific dialectal norms (Geeslin, Garcia-Amaya, Hasler-Barker, Henriksen, & Killam, 2010), and…

  20. Traditional-Aged College Juniors' Career Planning Self-Efficacy: A Case Study

    ERIC Educational Resources Information Center

    Sherman, Dawn C.

    2012-01-01

    The purpose of this single-site case study was to explore and describe traditional-age college juniors' reports of self-efficacy (Bandura, 1997) regarding Career Planning (Barker & Kellen, 1998). More specifically, the career planning confidence levels of college juniors enrolled in a required career development course at a private…

  1. 9 CFR 151.9 - Recognized breeds and books of record.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Guernsey English Guernsey Herd Book English Guernsey Cattle Society, J. W. Barker, secretary, Mappin House...., London, W. 1, England. 1309 Welsh Welsh Black Cattle Herd Book Welsh Black Cattle Society, G. Williams..., Ireland. Berkshire Gloucestershire Old Spots. Large Black 6002 Large WhiteMiddle White Herd Book of...

  2. 9 CFR 151.9 - Recognized breeds and books of record.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Guernsey English Guernsey Herd Book English Guernsey Cattle Society, J. W. Barker, secretary, Mappin House...., London, W. 1, England. 1309 Welsh Welsh Black Cattle Herd Book Welsh Black Cattle Society, G. Williams..., Ireland. Berkshire Gloucestershire Old Spots. Large Black 6002 Large WhiteMiddle White Herd Book of...

  3. 9 CFR 151.9 - Recognized breeds and books of record.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Guernsey English Guernsey Herd Book English Guernsey Cattle Society, J. W. Barker, secretary, Mappin House...., London, W. 1, England. 1309 Welsh Welsh Black Cattle Herd Book Welsh Black Cattle Society, G. Williams..., Ireland. Berkshire Gloucestershire Old Spots. Large Black 6002 Large WhiteMiddle White Herd Book of...

  4. 9 CFR 151.9 - Recognized breeds and books of record.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Guernsey English Guernsey Herd Book English Guernsey Cattle Society, J. W. Barker, secretary, Mappin House...., London, W. 1, England. 1309 Welsh Welsh Black Cattle Herd Book Welsh Black Cattle Society, G. Williams..., Ireland. Berkshire Gloucestershire Old Spots. Large Black 6002 Large WhiteMiddle White Herd Book of...

  5. 9 CFR 151.9 - Recognized breeds and books of record.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Guernsey English Guernsey Herd Book English Guernsey Cattle Society, J. W. Barker, secretary, Mappin House...., London, W. 1, England. 1309 Welsh Welsh Black Cattle Herd Book Welsh Black Cattle Society, G. Williams..., Ireland. Berkshire Gloucestershire Old Spots. Large Black 6002 Large WhiteMiddle White Herd Book of...

  6. Can In Utero Exposures Program an Increased Risk for Diseases Later in Life?

    EPA Science Inventory

    In the early 1990's, David Barker and his colleagues studied the relationship between the incidence of coronary heart disease and birth weight in a population of adult men and women in Hertfordshire, England. They found an inverse correlation between the incidence of coronary hea...

  7. 78 FR 25331 - Self-Regulatory Organizations; Financial Industry Regulatory Authority, Inc.; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-30

    .... 68700 (Jan. 18, 2013), 78 FR 5542. \\4\\ See Letter from Charles Barker, dated Jan. 29, 2013; Letter from... from Lisa Catalano, Esq., dated Feb. 18, 2013. \\5\\ See Securities Exchange Act Release No. 69063, 78 FR..., dated Feb. 13, 2013; Letter from Bert Savage, dated Feb. 13, 2013; Letter from William A. Jacobson,...

  8. EMBRYONIC AND FETAL PROGRAMMING OF PHYSIOLOGICAL DISORDERS IN ADULTHOOD

    EPA Science Inventory

    In the past decade, numerous epidemiological studies have indicated strong inverse associations between birth weight and risk of coronary heart disease, hypertension, type 2-diabetes and other diseases in adulthood. The ¿Barker hypothesis¿ thus postulates that a number of organ ...

  9. Improving Exam Results, but to What End? The Limitations of New Labour's Control Mechanism for Schools: Assessment-Based Accountability

    ERIC Educational Resources Information Center

    Mansell, Warwick

    2011-01-01

    Bernard Barker's thesis that schools have been undermined over the past quarter of a century by a damaging combination of top-down, centralised reform and a desire to impose a market philosophy on education is powerful. This article analyses the nature of the apparatus of control--both statist and free-market--which has been applied to schools…

  10. Saudi payload specialists during tour of center

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Sultan Salman Abdelazize Al-Saud and Abdulmohsen Hamad Al-Bassan, payload specialists from Saudi Arabia, are briefed in one of the mission control center support rooms by Kathleen V. Cannon (facing camera), payloads officer. Looking on is Erlinda Stevenson, secretary in the payload specialist coordination office (29713); Visitors tour the payload operations control center (POCC) in the mission control center during a Spacelab 3 simulation (29714); Visitors pose for picture in one of the Mission Control Center support rooms (29715); Visitors briefed by Kathleen V. Cannon (right) in one of the Mission Control Center support rooms. Erlinda Stevenson is also pictured (29716).

  11. STS-51G Crew Portrait

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The crew assigned to the STS-51G mission included (kneeling front left to right) Daniel C. Brandenstein, commander; and John O. Creighton, pilot. Standing, left to right, are mission specialists Shannon W. Lucid, Steven R. Nagel, and John M. Fabian; and payload specialists Sultan Salman Al-Saud, and Patrick Baudrey. Launched aboard the Space Shuttle Discovery on June 17, 1985 at 7:33:00 am (EDT), the STS-51G mission's primary payloads were three communications satellites: MORELOS-A for Mexico; ARABSAT-A , for Arab Satellite communications; and TELSTAR-3D, for ATT.

  12. View of the STS 51-L Memorial service on JSC's main mall

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Memorial services for the Challenger Seven were conducted on the morning of Jan. 31, 1986 at JSC's main mall. Among those in attendance were former and present astronauts and Space Shuttle payload specialists (PS). U.S. Sen. Jake Garn (R., Utah) vists at center with Sultan Salman Abdelazize Al-Saud of Saudi Arabia. Others pictured include German PS Ulf Merbold, French PS Patrick Baudry and NASA Astronauts Robert L. Stewart, Marsha S. Ivins, David C. Leestma and C. Gordon Fullerton, along with former astronaut Eugene A. Cernan.

  13. Vagueness as Probabilistic Linguistic Knowledge

    NASA Astrophysics Data System (ADS)

    Lassiter, Daniel

    Consideration of the metalinguistic effects of utterances involving vague terms has led Barker [1] to treat vagueness using a modified Stalnakerian model of assertion. I present a sorites-like puzzle for factual beliefs in the standard Stalnakerian model [28] and show that it can be resolved by enriching the model to make use of probabilistic belief spaces. An analogous problem arises for metalinguistic information in Barker's model, and I suggest that a similar enrichment is needed here as well. The result is a probabilistic theory of linguistic representation that retains a classical metalanguage but avoids the undesirable divorce between meaning and use inherent in the epistemic theory [34]. I also show that the probabilistic approach provides a plausible account of the sorites paradox and higher-order vagueness and that it fares well empirically and conceptually in comparison to leading competitors.

  14. Record length, mass, and clutch size in the nonindigenous Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), in Florida

    USGS Publications Warehouse

    Krysko, Kenneth L.; Hart, Kristen M.; Smith, Brian J.; Selby, Thomas H.; Cherkiss, Michael S.; Coutu, Nicholas T.; Reichart, Rebecca M.; Nuñez, Leroy P.; Mazzotti, Frank J.; Snow, Ray W.

    2012-01-01

    The Burmese Python, Python bivittatus Kuhl 1820 (Squamata: Pythonidae), is indigenous to northern India,east to southern China, and south to Vietnam and a few islands in Indonesia (Barker and Barker 2008, Reed and Rodda 2009). This species has been introduced since at least 1979 in southern Florida, USA, where it likely began reproducing and became established during the 1980s (Meshaka et al. 2000, Snowet al. 2007b,Kraus 2009, Krysko et al. 2011, Willson et al. 2011). Python bivittatus has been documented in Florida consuming a variety of mammals and birds, and the American Alligator(Alligator mississippiensis) (Snowet al. 2007a, 2007b; Harvey et al. 2008; Rochford et al. 2010b; Holbrook and Chesnes 2011), many of which are protected species. Herein, we provide details on two of the largest known wild P. bivittatus in Florida to date, including current records on length,mass,clutch size, and diet.

  15. A Cosmological Model with Negative Constant Deceleration Parameter in a General Scalar-Tensor Theory of Gravitation

    NASA Astrophysics Data System (ADS)

    Rao, V. U. M.; Sree Devi Kumari, G.

    2012-01-01

    Spatially homogeneous and anisotropic LRS Bianchi type-I metric is considered in the framework of Nordtvedt-Barker's general scalar-tensor theory of gravitation when the source for the energy momentum tensor is a perfect fluid. With the help of a special law of variation for Hubble's parameter proposed by Berman (Nuovo Cim. B. 74:182, 1983) a cosmological model with negative constant deceleration parameter is obtained. Some physical and kinematical properties of the model are also discussed.

  16. Equation of state and liquid-vapour equilibrium in a triangle-well fluid

    NASA Astrophysics Data System (ADS)

    Rivera, L. D.; Robles, M.; López de Haro, M.

    2012-06-01

    The second-order thermodynamic perturbation theory formulation of Barker and Henderson is used to derive the equation of state of the triangle-well fluid. This is combined with the rational function approximation to the radial distribution function of the hard-sphere fluid. Results are obtained for the critical parameters and the liquid-vapour coexistence curve for various values of the range of the potential. A comparison with available simulation data is presented.

  17. On analytic design of loudspeaker arrays with uniform radiation characteristics

    PubMed

    Aarts; Janssen

    2000-01-01

    Some notes on analytical derived loudspeaker arrays with uniform radiation characteristics are presented. The array coefficients are derived via analytical means and compared with so-called maximal flat sequences known from telecommunications and information theory. It appears that the newly derived array, i.e., the quadratic phase array, has a higher efficiency than the Bessel array and a flatter response than the Barker array. The method discussed admits generalization to the design of arrays with desired nonuniform radiating characteristics.

  18. A simplified perturbation theory for equilibrium properties of triangular-well fluids

    NASA Astrophysics Data System (ADS)

    Largo, J.; Solana, J. R.

    2000-09-01

    A simple expression for the first coordination shell of the radial distribution function of the reference hard-sphere fluid is used in combination with Barker-Henderson perturbation theory to obtain the thermodynamic properties of triangular-well fluids. These properties are expressed analytically in terms of density, temperature, and range of the potential. It is found that the results are accurate for a wide range of densities and temperatures in comparison with existing simulation data.

  19. Coded excitation for infrared non-destructive testing of carbon fiber reinforced plastics.

    PubMed

    Mulaveesala, Ravibabu; Venkata Ghali, Subbarao

    2011-05-01

    This paper proposes a Barker coded excitation for defect detection using infrared non-destructive testing. Capability of the proposed excitation scheme is highlighted with recently introduced correlation based post processing approach and compared with the existing phase based analysis by taking the signal to noise ratio into consideration. Applicability of the proposed scheme has been experimentally validated on a carbon fiber reinforced plastic specimen containing flat bottom holes located at different depths.

  20. Open abdomen in gastrointestinal surgery: Which technique is the best for temporary closure during damage control?

    PubMed Central

    Ribeiro Junior, Marcelo A F; Barros, Emily Alves; de Carvalho, Sabrina Marques; Nascimento, Vinicius Pereira; Cruvinel Neto, José; Fonseca, Alexandre Zanchenko

    2016-01-01

    AIM To compare the 3 main techniques of temporary closure of the abdominal cavity, vacuum assisted closure (vacuum-assisted closure therapy - VAC), Bogota bag and Barker technique, in damage control surgery. METHODS After systematic review of the literature, 33 articles were selected to compare the efficiency of the three procedures. Criteria such as cost, infections, capacity of reconstruction of the abdominal wall, diseases associated with the technique, among others were analyzed. RESULTS The Bogota bag and Barker techniques present as advantage the availability of material and low cost, what is not observed in the VAC procedure. The VAC technique is the most efficient, not only because it reduces the tension on the boarders of the lesion, but also removes stagnant fluids and debris and acts at cellular level increasing cell proliferation and division. Bogota bag presents the higher rates of skin laceration and evisceration, greater need for a stent for draining fluids and wash-ups, higher rates of intestinal adhesion to the abdominal wall. The Barker technique presents lack of efficiency in closing the abdominal wall and difficulty on maintaining pressure on the dressing. The VAC dressing can generate irritation and dermatitis when the drape is applied, in addition to pain, infection and bleeding, as well as toxic shock syndrome, anaerobic sepsis and thrombosis. CONCLUSION The VAC technique, showed to be superior allowing a better control of liquid on the third space, avoiding complications such as fistula with small mortality, low infection rate, and easier capability on primary closure of the abdominal cavity.

  1. STS 51-G crewmembers undergoing emergency egress training

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Mission specialist John M. Fabian, STS 51-G, listens to briefing on use of the Sky-Genie as an aid for emergency egress from the Shuttle vehicle, during a training session in the Shuttle mockup and integration laboratory at JSC. Phillip Morgan, left, of McDonnell Douglas, lends a hand (31930); A portrait view of Sultan Salman Abdelazize Al-Saud during a training session in the Shuttle mockup and integration laboratory. He is wearing a flight suit and helmet (31931); Jean Loup Chretien, a spationaut representing the Centre National d'Etudes Spatiales (CMES) of France, participates in emergency egress training. He is shown suspended in the Sky-Genie about to be lowered from the top of the crew compartment trainer (31932).

  2. SDAV Viz July Progress Update: LANL

    SciTech Connect

    Sewell, Christopher Meyer

    2012-07-30

    SDAV Viz July Progress Update: (1) VPIC (Vector Particle in Cell) Kinetic Plasma Simulation Code - (a) Implemented first version of an in-situ adapter based on Paraview CoProcessing Library, (b) Three pipelines: vtkDataSetMapper, vtkContourFilter, vtkPistonContour, (c) Next, resolve issue at boundaries of processor domains; add more advanced viz/analysis pipelines; (2) Halo finding/merger trees - (a) Summer student Wathsala W. from University of Utah is working on data-parallel halo finder algorithm using PISTON, (b) Timo Bremer (LLNL), Valerio Pascucci (Utah), George Zagaris (Kitware), and LANL people are interested in using merger trees for tracking the evolution of halos in cosmo simulations; discussed possible overlap with work by Salman Habib and Katrin Heitmann (Argonne) during their visit to LANL 7/11; (3) PISTON integration in ParaView - Now available from ParaView github.

  3. Supercomputing Sheds Light on the Dark Universe

    SciTech Connect

    Salman Habib

    2012-11-15

    At Argonne National Laboratory, scientists are using supercomputers to shed light on one of the great mysteries in science today, the Dark Universe. With Mira, a petascale supercomputer at the Argonne Leadership Computing Facility, a team led by physicists Salman Habib and Katrin Heitmann will run the largest, most complex simulation of the universe ever attempted. By contrasting the results from Mira with state-of-the-art telescope surveys, the scientists hope to gain new insights into the distribution of matter in the universe, advancing future investigations of dark energy and dark matter into a new realm. The team's research was named a finalist for the 2012 Gordon Bell Prize, an award recognizing outstanding achievement in high-performance computing.

  4. Development of a new type of germanium detector for dark matter searches

    NASA Astrophysics Data System (ADS)

    Wei, Wenzhao

    Monte Carlo simulation is an important tool used to develop a better understanding of important physical processes. This thesis describes three Monte Carlo simulations used to understand germanium detector response to low energy nuclear recoils and radiogenic backgrounds for direct dark matter searches. The first simulation is the verification of Barker-Mei model, a theoretical model for calculating the ionization efficiency for germanium detector for the energy range of 1 - 100 keV. Utilizing the shape analysis, a bin-to-bin comparison between simulation and experimental data was performed for verifying the accuracy of the Barker-Mei model. A percentage difference within 4% was achieved between data and simulation, which showed the validity of the Barker-Mei model. The second simulation is the study of a new type of germanium detector for n/gamma discrimination at 77 K with plasma time difference in pulse shape. Due to the poor time resolution, conventional P-type Point Contact (PPC) and coaxial germanium detectors are not capable of discriminating nuclear recoils from electron recoils. In this thesis, a new idea of using great detector granularity and plasma time difference in pulse shape to discriminate nuclear recoils from electron recoils with planar germanium detectors in strings was discussed. The anticipated sensitivity of this new detector array is shown for detecting dark matter. The last simulation is a study of a new type of germanium-detector array serving as a PMT screening facility for ultra-low background dark matter experiments using noble liquid xenon as detector material such LUX/LZ and XENON100/XENON1T. A well-shaped germanium detector array and a PMT were simulated to study the detector response to the signal and background for a better understanding of the radiogenic gamma rays from PMTs. The detector efficiency and other detector performance were presented in this work.

  5. Open abdomen in gastrointestinal surgery: Which technique is the best for temporary closure during damage control?

    PubMed Central

    Ribeiro Junior, Marcelo A F; Barros, Emily Alves; de Carvalho, Sabrina Marques; Nascimento, Vinicius Pereira; Cruvinel Neto, José; Fonseca, Alexandre Zanchenko

    2016-01-01

    AIM To compare the 3 main techniques of temporary closure of the abdominal cavity, vacuum assisted closure (vacuum-assisted closure therapy - VAC), Bogota bag and Barker technique, in damage control surgery. METHODS After systematic review of the literature, 33 articles were selected to compare the efficiency of the three procedures. Criteria such as cost, infections, capacity of reconstruction of the abdominal wall, diseases associated with the technique, among others were analyzed. RESULTS The Bogota bag and Barker techniques present as advantage the availability of material and low cost, what is not observed in the VAC procedure. The VAC technique is the most efficient, not only because it reduces the tension on the boarders of the lesion, but also removes stagnant fluids and debris and acts at cellular level increasing cell proliferation and division. Bogota bag presents the higher rates of skin laceration and evisceration, greater need for a stent for draining fluids and wash-ups, higher rates of intestinal adhesion to the abdominal wall. The Barker technique presents lack of efficiency in closing the abdominal wall and difficulty on maintaining pressure on the dressing. The VAC dressing can generate irritation and dermatitis when the drape is applied, in addition to pain, infection and bleeding, as well as toxic shock syndrome, anaerobic sepsis and thrombosis. CONCLUSION The VAC technique, showed to be superior allowing a better control of liquid on the third space, avoiding complications such as fistula with small mortality, low infection rate, and easier capability on primary closure of the abdominal cavity. PMID:27648164

  6. Incorporating movement patterns to improve survival estimates for juvenile bull trout

    USGS Publications Warehouse

    Bowerman, Tracy; Budy, Phaedra

    2012-01-01

    Populations of many fish species are sensitive to changes in vital rates during early life stages, but our understanding of the factors affecting growth, survival, and movement patterns is often extremely limited for juvenile fish. These critical information gaps are particularly evident for bull trout Salvelinus confluentus, a threatened Pacific Northwest char. We combined several active and passive mark–recapture and resight techniques to assess migration rates and estimate survival for juvenile bull trout (70–170 mm total length). We evaluated the relative performance of multiple survival estimation techniques by comparing results from a common Cormack–Jolly–Seber (CJS) model, the less widely used Barker model, and a simple return rate (an index of survival). Juvenile bull trout of all sizes emigrated from their natal habitat throughout the year, and thereafter migrated up to 50 km downstream. With the CJS model, high emigration rates led to an extreme underestimate of apparent survival, a combined estimate of site fidelity and survival. In contrast, the Barker model, which allows survival and emigration to be modeled as separate parameters, produced estimates of survival that were much less biased than the return rate. Estimates of age-class-specific annual survival from the Barker model based on all available data were 0.218±0.028 (estimate±SE) for age-1 bull trout and 0.231±0.065 for age-2 bull trout. This research demonstrates the importance of incorporating movement patterns into survival analyses, and we provide one of the first field-based estimates of juvenile bull trout annual survival in relatively pristine rearing conditions. These estimates can provide a baseline for comparison with future studies in more impacted systems and will help managers develop reliable stage-structured population models to evaluate future recovery strategies.

  7. Mercedes-Benz water molecules near hydrophobic wall: integral equation theories vs Monte Carlo simulations.

    PubMed

    Urbic, T; Holovko, M F

    2011-10-01

    Associative version of Henderson-Abraham-Barker theory is applied for the study of Mercedes-Benz model of water near hydrophobic surface. We calculated density profiles and adsorption coefficients using Percus-Yevick and soft mean spherical associative approximations. The results are compared with Monte Carlo simulation data. It is shown that at higher temperatures both approximations satisfactory reproduce the simulation data. For lower temperatures, soft mean spherical approximation gives good agreement at low and at high densities while in at mid range densities, the prediction is only qualitative. The formation of a depletion layer between water and hydrophobic surface was also demonstrated and studied.

  8. Mercedes–Benz water molecules near hydrophobic wall: Integral equation theories vs Monte Carlo simulations

    PubMed Central

    Urbic, T.; Holovko, M. F.

    2011-01-01

    Associative version of Henderson-Abraham-Barker theory is applied for the study of Mercedes–Benz model of water near hydrophobic surface. We calculated density profiles and adsorption coefficients using Percus-Yevick and soft mean spherical associative approximations. The results are compared with Monte Carlo simulation data. It is shown that at higher temperatures both approximations satisfactory reproduce the simulation data. For lower temperatures, soft mean spherical approximation gives good agreement at low and at high densities while in at mid range densities, the prediction is only qualitative. The formation of a depletion layer between water and hydrophobic surface was also demonstrated and studied. PMID:21992334

  9. Mercedes-Benz water molecules near hydrophobic wall: Integral equation theories vs Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Urbic, T.; Holovko, M. F.

    2011-10-01

    Associative version of Henderson-Abraham-Barker theory is applied for the study of Mercedes-Benz model of water near hydrophobic surface. We calculated density profiles and adsorption coefficients using Percus-Yevick and soft mean spherical associative approximations. The results are compared with Monte Carlo simulation data. It is shown that at higher temperatures both approximations satisfactory reproduce the simulation data. For lower temperatures, soft mean spherical approximation gives good agreement at low and at high densities while in at mid range densities, the prediction is only qualitative. The formation of a depletion layer between water and hydrophobic surface was also demonstrated and studied.

  10. Multiple pollutant removal using the condensing heat exchanger. Task 3, Long term testing at the ECTC

    SciTech Connect

    Schulze, K.H.

    1996-01-01

    The objective of this task is to demonstrate long term operation of a condensing heat exchanger for coal-fired conditions. A small condensing heat exchanger will be installed at the Environmental Control Technology Center in Barker, New York. It will be installed downstream of the flue gas particulate removal system. The test will determine the amount of wear, if any, on the Teflon{trademark} covered internals of the heat exchanger. Visual inspection and measurements will be obtained for the Teflon{trademark} covered tubes during the test. The material wear study will conducted over a one year calendar period, and the CHX equipment will be operated to the fullest extent allowable.

  11. Experimental observations of structural relaxation in granular matter

    NASA Astrophysics Data System (ADS)

    Massalska-Arodź, M.; Mayer, J.; Brańkowski, J.; Ostrowicz, A.; Lisiecki, E.

    1997-01-01

    The relaxational changes of the electrical capacitance of a system of grains poured abruptly into a vessel capacitor have been observed. Two power-law decays have been found. The faster relaxation at the beginning has been interpreted as being driven by independent-grain motion. The later slower process has been ascribed to the collective reorganization of the granular system. The observations seem to be an experimental illustration of the computer simulation predictions of Mehta and Barker [Rep. Prog. Phys. 57, 383 (1994); Phys. Rev. A 45, 3435 (1992); Phys. Rev. Lett. 67, 394 (1991); Nature 364, 486 (1993); Phys. Rev. E 47, 184 (1993)].

  12. Sea surface temperatures in the North Atlantic Ocean from 30ka to 10ka

    NASA Astrophysics Data System (ADS)

    Barrack, Kerr; Greenop, Rosanna; Burke, Andrea; Barker, Stephen; Chalk, Thomas; Crocker, Anya

    2016-04-01

    Some of the most striking features of the Late Pleistocene interval are the rapid changes in climate between warmer interstadial and cold stadial periods which, when coupled, are termed Dansgaard-Oeschger (D-O) events. This shift between warm and cold climates has been interpreted to result from changes in the thermohaline circulation (Broecker et al., 1985) triggered by, for instance, freshwater input from the collapse of the Laurentide ice sheet (Zahn et al., 1997). However, a recent study suggests that major ice rafting events cannot be the 'trigger' for the centennial to millennial scale cooling events identified over the past 500kyr (Barker at al., 2015). Polar planktic foraminiferal and lithogenic/terrigenous grain counts reveal that the southward migration of the polar front occurs before the deposition of ice rafted debris and therefore the rafting of ice during stadial periods. Based upon this evidence, Barker et al. suggest that the transition to a stadial state is a non-linear response to gradual cooling in the region. In order to test this hypothesis, our study reconstructs sea surface temperature across D-O events and the deglaciation in the North Atlantic between 30ka and 10ka using Mg/ Ca paleothermometry in Globigerina bulloides at ODP Sites 980 and 983 (the same sites as used in Barker et al., 2015) with an average sampling resolution of 300 years. With our new record we evaluate the timing of surface ocean temperature change, frontal shift movement, and ice rafting to investigate variations in the temperature gradient across the polar front over D-O events. References: Barker, S., Chen, J., Gong, X., Jonkers, L., Knorr, G., Thornalley, D., 2015. Icebergs not the trigger for North Atlantic cold events. Nature, 520(7547), pp.333-336. Broecker, W.S., Peteer, D.M., Rind, D., 1985. Does the ocean-atmosphere system have more than one stable mode of operation? Nature, 315 (6014), pp.21-26. Zahn, R., Schönfeld, J., Kudrass, H.-R., Park, M

  13. In Franklin's Path: Establishing Physics at the University of Pennsylvania

    NASA Astrophysics Data System (ADS)

    Halpern, Paul

    2008-04-01

    In 1751 Benjamin Franklin established the Academy of Philadelphia, the precursor of the University of Pennsylvania. Among its curricular mandates he envisioned included ``Natural and Mechanic History,'' using a popular text he suggested by No"el Antoine Pluche that encompassed optics and celestial dynamics among its subjects. This talk will trace the history of physics research and education at Penn from its establishment, to the appointment of the first designated physics professor, George Frederic Barker, in 1873, to the opening of the Randall Morgan Laboratory in 1901 under the directorship of Arthur Goodspeed, and finally to the inauguration of the David Rittenhouse Laboratory in 1954 under the university leadership of Gaylord Harnwell.

  14. Pulse Voltammetry

    NASA Astrophysics Data System (ADS)

    Stojek, Zbigniew

    The idea of imposing potential pulses and measuring the currents at the end of each pulse was proposed by Barker in a little-known journal as early as in 1958 [1]. However, the first reliable trouble-free and affordable polarographs offering voltammetric pulse techniques appeared on the market only in the 1970s. This delay was due to some limitations on the electronic side. In the 1990s, again substantial progress in electrochemical pulse instrumentation took place. This was related to the introduction of microprocessors, computers, and advanced software.

  15. Mercedes-Benz water molecules near hydrophobic wall: integral equation theories vs Monte Carlo simulations.

    PubMed

    Urbic, T; Holovko, M F

    2011-10-01

    Associative version of Henderson-Abraham-Barker theory is applied for the study of Mercedes-Benz model of water near hydrophobic surface. We calculated density profiles and adsorption coefficients using Percus-Yevick and soft mean spherical associative approximations. The results are compared with Monte Carlo simulation data. It is shown that at higher temperatures both approximations satisfactory reproduce the simulation data. For lower temperatures, soft mean spherical approximation gives good agreement at low and at high densities while in at mid range densities, the prediction is only qualitative. The formation of a depletion layer between water and hydrophobic surface was also demonstrated and studied. PMID:21992334

  16. GeSi Raman spectra vs. local clustering/anticlustering: Percolation scheme and ab initio calculations

    NASA Astrophysics Data System (ADS)

    Pagès, O.; Hussein, R. Hajj; Torres, V. J. B.

    2013-07-01

    We formalize within the percolation scheme that operates along the linear chain approximation, i.e., at one dimension (1D), an intrinsic ability behind Raman scattering to achieve a quantitative insight into local clustering/anticlustering in an alloy, using GeSi as a case study. For doing so, we derive general expressions of the individual fractions of the six GeSi percolation-type oscillators [1×(Ge-Ge), 3×(Ge-Si), 2×(Si-Si)], which monitor directly the Raman intensities, via a relevant order parameter κ. This is introduced by adapting to the 1D oscillators of the GeSi-diamond version of the 1D-percolation scheme, i.e., along a fully consistent 1D treatment, the approach originally used by Verleur and Barker for the three-dimensional (3D) oscillators of their 1D-cluster scheme applying to zincblende alloys [H. W. Verleur and A. S. Barker, Phys. Rev. 149, 715 (1966)], a somehow problematic one in fact, due to its 3D-1D ambivalence. Predictive κ-dependent intensity-interplays between the Ge0.5Si0.5 Raman lines are confronted with existing experimental data and with ab initio Raman spectra obtained by using (32-atom) disordered supercells matching the required κ values, with special attention to the Ge-Si triplet and to the Si-Si doublet, respectively.

  17. An overview on the effect of manufacturing on the shock response of polymers

    NASA Astrophysics Data System (ADS)

    Kister, G.; Wood, D. C.; Appleby-Thomas, G. J.; Leighs, J. A.; Goff, M.; Barnes, N. R.; Hazell, P. J.

    2014-05-01

    Scatter and non-linearity of the Hugoniot in the Us-up plane has been seen in a number of polymers including poly(methyl methacrylate) (PMMA), the polymer considered here. In this study the plate impact technique has been used to investigate the shock response of PMMA between particle velocities of 0.13 and 0.77 mm μs-1. From this data no scatter was seen between our data and the experimental data of Barker and Hollenbach, and Carter and Marsh. Also a linear Hugoniot in the Us-up plane was found, with the equation Us = 2.99 + 0.92up. The non-linearity observed by Barker and Hollenbach was not present in this data, probably due to the non-linearity occur at particle velocities of below 0.13 mm μs-1, within their experimental data. Gruneisen gamma has also been briefly considered using a shock reverberation experiment but more work is needed before a value can be ascertained.

  18. The application of coded excitation technology in medical ultrasonic Doppler imaging

    NASA Astrophysics Data System (ADS)

    Li, Weifeng; Chen, Xiaodong; Bao, Jing; Yu, Daoyin

    2008-03-01

    Medical ultrasonic Doppler imaging is one of the most important domains of modern medical imaging technology. The application of coded excitation technology in medical ultrasonic Doppler imaging system has the potential of higher SNR and deeper penetration depth than conventional pulse-echo imaging system, it also improves the image quality, and enhances the sensitivity of feeble signal, furthermore, proper coded excitation is beneficial to received spectrum of Doppler signal. Firstly, this paper analyzes the application of coded excitation technology in medical ultrasonic Doppler imaging system abstractly, showing the advantage and bright future of coded excitation technology, then introduces the principle and the theory of coded excitation. Secondly, we compare some coded serials (including Chirp and fake Chirp signal, Barker codes, Golay's complementary serial, M-sequence, etc). Considering Mainlobe Width, Range Sidelobe Level, Signal-to-Noise Ratio and sensitivity of Doppler signal, we choose Barker codes as coded serial. At last, we design the coded excitation circuit. The result in B-mode imaging and Doppler flow measurement coincided with our expectation, which incarnated the advantage of application of coded excitation technology in Digital Medical Ultrasonic Doppler Endoscope Imaging System.

  19. Heat capacity of square-well fluids of variable width

    NASA Astrophysics Data System (ADS)

    Largo, J.; Solana, J. R.; Acedo, L.; Santos, A.

    We have obtained by Monte Carlo NVT simulations the constant-volume excess heat capacity of square-well fluids for several temperatures, densities and potential widths. Heat capacity is a thermodynamic property much more sensitive to the accuracy of a theory than other thermodynamic quantities, such as the compressibility factor. This is illustrated by comparing the reported simulation data for the heat capacity with the theoretical predictions given by the Barker-Henderson perturbation theory as well as with those given by a non-perturbative theoretical model based on Baxter's solution of the Percus-Yevick integral equation for sticky hard spheres. Both theories give accurate predictions for the equation of state. By contrast, it is found that the Barker-Henderson theory strongly underestimates the excess heat capacity for low to moderate temperatures, whereas a much better agreement between theory and simulation is achieved with the non-perturbative theoretical model, particularly for small well widths, although the accuracy of the latter worsens for high densities and low temperatures, as the well width increases.

  20. Vitrinite reflectance of sinkhole coals, east central Missouri fire clay district

    SciTech Connect

    Laudon, R.C. . Dept. of Geology and Geophysics)

    1993-03-01

    East central Missouri contains numerous sinkholes many of which are filled with commercial quantities of fire clay and some contain small amounts of coal. Vitrinite reflectance averages from 513 samples taken from eleven of these coals ranged from 0.71 to 0.78. Data were remarkably consistent and no local trends were observed. Using Barker and Goldstein (1990) and Barker and Pawlewicz (1986) temperature correlations, these measurements suggest that the coals have been heated to temperatures on the order of 108 C to 128 C (average = 116). These temperatures are considered anomalously high when compared against known geothermal gradients and burial depths for these rocks. The temperatures suggest that the sinkhole coals have been heated by some thermal event, possibly associated with Mississippi Valley type mineralization. These temperatures are consistent with regional trends in the state. This data, when combined with other vitrinite reflectance and fluid inclusion data (right), suggest that southwest Missouri (Tristate) and southeast Missouri (Viburnum Trend) were hot spots, and that temperatures decrease regionally away from these two areas.

  1. Experimental investigation of the transient dynamics of slow light in ruby

    NASA Astrophysics Data System (ADS)

    Wisniewski-Barker, Emma; Gibson, Graham M.; Franke-Arnold, Sonja; Shi, Zhimin; Narum, Paul; Boyd, Robert W.; Padgett, Miles J.

    2014-12-01

    When a pulsed light beam propagates through ruby, it is delayed by a slow-light mechanism. This mechanism has been the subject of debate (Wisniewski-Barker et al 2013 New J. Phys. 15 083020; Kozlov et al 2014 New J. Phys. 16 038001; Wisniewski-Barker et al 2014 New J. Phys. 16 038002). To distinguish between the two main proposed mechanisms, we investigate the trailing edge of a square-wave pulsed laser beam propagating through ruby. Our observation of a pronounced tail on the trailing edge of the transmitted pulse cannot be explained solely by the effects of a time-varying absorber acting upon the incident pulse. Therefore, our observation of the creation of a tail at the trailing edge of the pulse provides evidence for a complicated model of slow light in ruby that requires more than pulse reshaping. The different delays of individual Fourier components of the pulse signal explain the pulse distortion that occurs upon transmission through the ruby and must be accounted for by any model that attempts to describe the effects of slow light in ruby.

  2. Comment on ‘Evidence of slow-light effects from rotary drag of structured beams’

    NASA Astrophysics Data System (ADS)

    Kozlov, G. G.; Poltavtsev, S. V.; Ryzhov, I. I.; Zapasskii, V. S.

    2014-03-01

    The paper Wisniewski-Barker E et al (2013 New J. Phys. 15 083020) is intended to distinguish experimentally between two mechanisms of pulse delay in ruby and to provide evidence in favor of the slow-light model. The proposed test is based on the idea of monitoring time delay of a ‘dark pulse’ or ‘intensity null’, rather than that of some Gaussian-like pulse. We show that, because of certain experimental inconsistencies, the results of the measurements do not allow one to prefer one of the models and, thus, are interpreted inadequately. In this comment, we propose and realize a simple modification of the experiment Wisniewski-Barker E et al (2013 New J. Phys. 15 083020), which allows us to unambiguously resolve this dilemma. We show that the effect of pulse delay in ruby is perfectly described by the simple model of pulse reshaping and does not require invoking the coherent population oscillation-based slow-light effects.

  3. Fetal origins of adult disease.

    PubMed

    Calkins, Kara; Devaskar, Sherin U

    2011-07-01

    Dr. David Barker first popularized the concept of fetal origins of adult disease (FOAD). Since its inception, FOAD has received considerable attention. The FOAD hypothesis holds that events during early development have a profound impact on one's risk for development of future adult disease. Low birth weight, a surrogate marker of poor fetal growth and nutrition, is linked to coronary artery disease, hypertension, obesity, and insulin resistance. Clues originally arose from large 20th century, European birth registries. Today, large, diverse human cohorts and various animal models have extensively replicated these original observations. This review focuses on the pathogenesis related to FOAD and examines Dr. David Barker's landmark studies, along with additional human and animal model data. Implications of the FOAD extend beyond the low birth weight population and include babies exposed to stress, both nutritional and nonnutritional, during different critical periods of development, which ultimately result in a disease state. By understanding FOAD, health care professionals and policy makers will make this issue a high health care priority and implement preventive measures and treatment for those at higher risk for chronic diseases.

  4. Nonlinear Binormal Flow of Vortex Filaments

    NASA Astrophysics Data System (ADS)

    Strong, Scott; Carr, Lincoln

    2015-11-01

    With the current advances in vortex imaging of Bose-Einstein condensates occurring at the Universities of Arizona, São Paulo and Cambridge, interest in vortex filament dynamics is experiencing a resurgence. Recent simulations, Salman (2013), depict dissipative mechanisms resulting from vortex ring emissions and Kelvin wave generation associated with vortex self-intersections. As the local induction approximation fails to capture reconnection events, it lacks a similar dissipative mechanism. On the other hand, Strong&Carr (2012) showed that the exact representation of the velocity field induced by a curved segment of vortex contains higher-order corrections expressed in powers of curvature. This nonlinear binormal flow can be transformed, Hasimoto (1972), into a fully nonlinear equation of Schrödinger type. Continued transformation, Madelung (1926), reveals that the filament's square curvature obeys a quasilinear scalar conservation law with source term. This implies a broader range of filament dynamics than is possible with the integrable linear binormal flow. In this talk we show the affect higher-order corrections have on filament dynamics and discuss physical scales for which they may be witnessed in future experiments. Partially supported by NSF.

  5. Trabasa - Traditional Architecture Recorded by Means of Building Archaeology in Saudi Arabia: Workshop in Jeddah

    NASA Astrophysics Data System (ADS)

    Herbig, U.; Jäger-Klein, C.; Mayer, I.; Mortada, H.; Styhler-Aydın, G.

    2013-07-01

    Saudi Arabia has a rich architectural heritage that can be found in all regions of the vast country. Except for a small number of publications the recording and documentation of the traditional built environment was not content of detailed scientific investigations so far. But with the increasing decay of the architectural heritage the interest for this kind of research is rising. A mirror of this efforts is the National Built Heritage Forum, annual conference, launched in 2010 by his excellency Prince Sultan bin Salman bin Abdulaziz Al Saud and the Saudi Commission for Tourism and Antiquities (SCTA). In that frame Saudi universities are intensifying research and educational programs for the research of traditional architecture. In 2008 the Department of Architecture of the College of Environmental Design at the King Abdulaziz University established a cooperation with the Department of History of Architecture and Building Archaeology of the Vienna University of Technology with the aim to start an exchange of knowledge and experience in building archaeology and building survey. An important part of this cooperation was a workshop for staff and students in the historic centre of Jeddah. The aim was to train methods and techniques on typical examples in the old town of Jeddah, Al Balad. This paper is describing the layout of the workshop, the process of the work and examples of the results.

  6. Evaluation of knowledge of Health care professionals on warfarin interactions with drug and herb medicinal in Central Saudi Arabia

    PubMed Central

    Al-Arifi, Mohamed N.; Wajid, Syed; Al-Manie, Nawaf K.; Al-Saker, Faisal M.; Babelgaith, Salmeen D.; Asiri, Yousif A.; Sales, Ibrahim

    2016-01-01

    Objectives: To evaluate health care professionals’ knowledge on warfarin interactions with drugs and herbs. Methods: A self-administered questionnaire was developed to assess health care professionals’ knowledge on warfarin interactions with drug and herb. Respondents were asked to classify 15 drugs that may effect on warfarin action as “enhance”, “inhibit “, “no effect”. The study sample involved health care professionals (physicians, pharmacists and nurses) from king Salman hospital, Saudi Arabia. Results: About 92.2% of health care professionals identified warfarin interactions with aspirin, 4.4% for warfarin and fluoxetine. Warfarin and cardiac agents (atenolol) was correctly identified by 11.1% of respondents. In warfarin –herb interactions section, the majority of respondents (66.7%) identified the interaction between green tea and warfarin. Approximately one-third of respondents (n=33) correctly classified warfarin interactions with cardamom. No significant difference was found between the health care professionals (p=0.49) for warfarin-drug interactions knowledge score and p= 0.52 for warfarin- herb interactions knowledge score. Conclusion: This study suggests that health care professionals’ knowledge of warfarin- drug-herb interactions was inadequate. Therefore, health care professionals should receive more education programs about drug-drug/herb interactions to provide appropriate patient counseling and optimal therapeutic outcomes. PMID:27022381

  7. Magnetic fields in noninvasive brain stimulation.

    PubMed

    Vidal-Dourado, Marcos; Conforto, Adriana Bastos; Caboclo, Luis Otávio Sales Ferreira; Scaff, Milberto; Guilhoto, Laura Maria de Figueiredo Ferreira; Yacubian, Elza Márcia Targas

    2014-04-01

    The idea that magnetic fields could be used therapeutically arose 2000 years ago. These therapeutic possibilities were expanded after the discovery of electromagnetic induction by the Englishman Michael Faraday and the American Joseph Henry. In 1896, Arsène d'Arsonval reported his experience with noninvasive brain magnetic stimulation to the scientific French community. In the second half of the 20th century, changing magnetic fields emerged as a noninvasive tool to study the nervous system and to modulate neural function. In 1985, Barker, Jalinous, and Freeston presented transcranial magnetic stimulation, a relatively focal and painless technique. Transcranial magnetic stimulation has been proposed as a clinical neurophysiology tool and as a potential adjuvant treatment for psychiatric and neurologic conditions. This article aims to contextualize the progress of use of magnetic fields in the history of neuroscience and medical sciences, until 1985. PMID:23787954

  8. Plasma Medicine

    NASA Astrophysics Data System (ADS)

    Laroussi, M.; Kong, M. G.; Morfill, G.; Stolz, W.

    2012-05-01

    Foreword R. Satava and R. J. Barker; Part I. Introduction to Non-equilibrium Plasma, Cell Biology, and Contamination: 1. Introduction M. Laroussi; 2. Fundamentals of non-equilibrium plasmas M. Kushner and M. Kong; 3. Non-equilibrium plasma sources M. Laroussi and M. Kong; 4. Basic cell biology L. Greene and G. Shama; 5. Contamination G. Shama and B. Ahlfeld; Part II. Plasma Biology and Plasma Medicine: 6. Common healthcare challenges G. Isbary and W. Stolz; 7. Plasma decontamination of surfaces M. Kong and M. Laroussi; 8. Plasma decontamination of gases and liquids A. Fridman; 9. Plasma-cell interaction: prokaryotes M. Laroussi and M. Kong; 10. Plasma-cell interaction: eukaryotes G. Isbary, G. Morfill and W. Stolz; 11. Plasma based wound healing G. Isbary, G. Morfill and W. Stolz; 12. Plasma ablation, surgery, and dental applications K. Stalder, J. Woloszko, S. Kalghatgi, G. McCombs, M. Darby and M. Laroussi; Index.

  9. Experimental Determination of Densities and Isobaric Vapor-Liquid Equilibria of Methyl Acetate and Ethyl Acetate with Alcohols (C3 and C4) at 0.3 MPa

    NASA Astrophysics Data System (ADS)

    Susial, Pedro; Estupiñan, Esteban J.; Castillo, Victor D.; Rodríguez-Henríquez, José J.; Apolinario, José C.

    2013-10-01

    The densities and excess volumes were determined at 298.15 K for the methyl acetate + 1-propanol, methyl acetate + 1-butanol, and ethyl acetate + 1-butanol mixtures. The vapor-liquid equilibria data at 0.3 MPa for these binary systems were obtained using a stainless steel equilibrium still. The activity coefficients were obtained from the experimental data using the Hayden and O’Connell method and the Yen and Woods equation. The binary systems in this study showed positive deviations from ideality. The experimental VLE data were verified with the point-to-point test of van Ness using the Barker routine and the Fredenslund criterion. The different versions of the UNIFAC and the ASOG group contribution models were applied.

  10. Perturbation theory for multicomponent fluids based on structural properties of hard-sphere chain mixtures

    NASA Astrophysics Data System (ADS)

    Hlushak, Stepan

    2015-09-01

    An analytical expression for the Laplace transform of the radial distribution function of a mixture of hard-sphere chains of arbitrary segment size and chain length is used to rigorously formulate the first-order Barker-Henderson perturbation theory for the contribution of the segment-segment dispersive interactions into thermodynamics of the Lennard-Jones chain mixtures. Based on this approximation, a simple variant of the statistical associating fluid theory is proposed and used to predict properties of several mixtures of chains of different lengths and segment sizes. The theory treats the dispersive interactions more rigorously than the conventional theories and provides means for more accurate description of dispersive interactions in the mixtures of highly asymmetric components.

  11. Dissociative adsorption of O2 on unreconstructed metal (100) surfaces: Pathways, energetics, and sticking kinetics

    NASA Astrophysics Data System (ADS)

    Liu, Da-Jiang; Evans, James W.

    2014-05-01

    An accurate description of oxygen dissociation pathways and kinetics for various local adlayer environments is key for an understanding not just of the coverage dependence of oxygen sticking, but also of reactive steady states in oxidation reactions. Density functional theory analysis for M(100) surfaces with M =Pd, Rh, and Ni, where O prefers the fourfold hollow adsorption site, does not support the traditional Brundle-Behm-Barker picture of dissociative adsorption onto second-nearest-neighbor hollow sites with an additional blocking constraint. Rather adsorption via neighboring vicinal bridge sites dominates, although other pathways can be active. The same conclusion also applies for M =Pt and Ir, where oxygen prefers the bridge adsorption site. Statistical mechanical analysis is performed based on kinetic Monte Carlo simulation of a multisite lattice-gas model consistent with our revised picture of adsorption. This analysis determines the coverage and temperature dependence of sticking for a realistic treatment of the oxygen adlayer structure.

  12. A fully implicit domain decomposition based ALE framework for three-dimensional fluid-structure interaction with application in blood flow computation

    NASA Astrophysics Data System (ADS)

    Wu, Yuqi; Cai, Xiao-Chuan

    2014-02-01

    Due to the rapid advancement of supercomputing hardware, there is a growing interest in parallel algorithms for modeling the full three-dimensional interaction between the blood flow and the arterial wall. In [4], Barker and Cai developed a parallel framework for solving fluid-structure interaction problems in two dimensions. In this paper, we extend the idea to three dimensions. We introduce and study a parallel scalable domain decomposition method for solving nonlinear monolithically coupled systems arising from the discretization of the coupled system in an arbitrary Lagrangian-Eulerian framework with a fully implicit stabilized finite element method. The investigation focuses on the robustness and parallel scalability of the Newton-Krylov algorithm preconditioned with an overlapping additive Schwarz method. We validate the proposed approach and report the parallel performance for some patient-specific pulmonary artery problems. The algorithm is shown to be scalable with a large number of processors and for problems with millions of unknowns.

  13. Ionization efficiency study for low energy nuclear recoils in germanium

    NASA Astrophysics Data System (ADS)

    Barker, D.; Wei, W.-Z.; Mei, D.-M.; Zhang, C.

    2013-08-01

    We used the internal conversion (E0 transition) of germanium-72 to indirectly measure the low energy nuclear recoils of germanium. Together with a reliable Monte Carlo package, in which we implement the internal conversion process, the data was compared to the Lindhard (k = 0.159) and Barker-Mei models. A shape analysis indicates that both models agree well with data in the region of interest within 4%. The most probable value (MPV) of the nuclear recoils obtained from the shape analysis is 17.5 ± 0.12 (sys) ±0.035 (stat) keV with an average path-length of 0.014 μm.

  14. What veterinary practice managers can learn from other health care professions.

    PubMed

    Wood, F

    1996-02-01

    Joel Barker, a noted futurist, points out that the best ideas usually come from outside an industry or profession. As a management consultant, I often get new ideas from industries completely unrelated to my clients' industry. For example, companies interested in offering outstanding customer service might study Nordstrom's, L.L. Bean, or Lexus. Those interested in world class distribution might research Federal Express or United Parcel Service. Airlines, trying to minimize downtime of jets at the terminal, learn secrets from Indianapolis 500 pit crews. Similarly, in observing optometrists and dentists, there are valuable lessons for veterinarians. Dentists identified a business model or organizational structure that generates healthy profits. Independent optometrists experienced the onslaught of intense competition from huge corporate players and weathered the storm. The veterinary profession is not so unique. By studying other professions, we need not recreate the wheel. PMID:8778948

  15. Historical saturated thickness of the Edwards-Trinity aquifer system and selected contiguous hydraulically connected units, west-central Texas

    USGS Publications Warehouse

    Ardis, Ann F.; Barker, Rene A.

    1993-01-01

    The purposes of this report are to illustrate the historical distribution of saturated thickness (hereafter referred to as the saturated thickness) in the Edwards-Trinity aquifer system, summarize the reasons for the variation in the saturated thickness, and relate the regional effects of this variation to the distribution of transmissivity. The saturated thickness map (sheet 2) was determined for most of the area by subtracting the altitude of the base of the aquifer system (Barker and Ardis, 1992) from the altitude of the historical potentiometric surface (Bush and others, 1993). Where the Edwards and Trinity aquifers are confined in the Balcones fault zone, the saturated thickness is defined by the thickness of the aquifer system, which was determined by subtracting the altitude of the base of the aquifer system from the altitude of the base of the Navarro-Del Rio confining unit (G.E. Groschen and W.G. Stein, U.S. Geological Survey, written commun, 1990).

  16. Killing Me Softly: The Fetal Origins Hypothesis*

    PubMed Central

    Almond, Douglas

    2013-01-01

    In the epidemiological literature, the fetal origins hypothesis associated with David J. Barker posits that chronic, degenerative conditions of adult health, including heart disease and type 2 diabetes, may be triggered by circumstance decades earlier, in utero nutrition in particular. Economists have expanded on this hypothesis, investigating a broader range of fetal shocks and circumstances and have found a wealth of later-life impacts on outcomes including test scores, educational attainment, and income, along with health. In the process, they have provided some of the most credible observational evidence in support of the hypothesis. The magnitude of the impacts is generally large. Thus, the fetal origins hypothesis has not only survived contact with economics, but has flourished. PMID:25152565

  17. Sustainable development of geothermal fields in the Pannonian Basin - A case study

    SciTech Connect

    Panu, Dumitru; Mitrofan, Horia; Serbu, Viorel

    1996-01-24

    As suggested by the discusssion of Barker, 1988, on the influence of flow dimension on the late-time behaviour of the generalized line source solution, it was inferred that observed long term reservoir pressure decline was an outcome of the 1D (linear) flow geometry, indicated by well tests. The detrimental effects of the reservoir pressure decline can be partly mitigated by taking advantage of the two-phase flow which occurs when methane, originally dissolved in the geothermal brine, is released within the well bore. Sustainable artesiar withdrawal scenarios for existing geothermal fields are devised, based on an accurate prediction of bottomhole pressure decline trends and an adequate selection of the diameter and length of the production tubing. Overall analysis and forecast are performed by an integrated reservoir & well bore simulator.

  18. A species pair of Bivesicula Yamaguti, 1934 (Trematoda: Bivesiculidae) in unrelated Great Barrier Reef fishes: implications for the basis of speciation in coral reef fish trematodes.

    PubMed

    Trieu, Nancy; Cutmore, Scott C; Miller, Terrence L; Cribb, Thomas H

    2015-07-01

    Combined morphological and molecular analysis shows that a species of Bivesicula Yamaguti, 1934 from four species of Apogonidae Günther [Nectamia fusca (Quoy & Gaimard), Ostorhinchus angustatus (Smith & Radcliffe), O. cookii (Macleay) and Taeniamia fucata (Cantor)] on the Great Barrier Reef is morphologically similar to, but clearly distinct from B. unexpecta Cribb, Bray & Barker, 1994 which infects a sympatric pomacentrid, Acanthochromis polyacanthus (Bleeker). Bivesicula neglecta n. sp. is proposed for the form from apogonids. Novel ITS2 rDNA sequences generated for the two species differ at just one consistent base position, implying that the two species are closely related. The combination of their close relationship, high but distinct specificity and co-occurrence suggests that speciation was driven by a recent host switching event enabled by similar dietary ecomorphology.

  19. Volcano monitoring using short wavelength infrared data from satellites

    NASA Technical Reports Server (NTRS)

    Rothery, D. A.; Francis, P. W.; Wood, C. A.

    1988-01-01

    It is shown that Landsat TM and MSS data provide useful and sometimes unique information on magmatic and fumarolic events at poorly monitored active volcanoes. The digital number data recorded in each spectral band by TM and MSS can be converted into spectral radiance, measured in W/sq m per micron per sr, using calibration data such as those provided by Markham and Barker (1986) and can provide temperature information on the lava fountain, lava lakes, pahoehoe flows, blocky lava, pyroclastic flow, and fumarole. The examples of Landsat data documenting otherwise unobserved precursors and/or activity include the September 1986 eruption of Lascar volcano, Chile; the continued presence of lava lakes at Erta 'Ale, Ethiopia (in the absence of any ground-based observations); and minor eruptions at Mount Erebus, Antarctica.

  20. Prenatal Programming of Mental Illness: Current Understanding of Relationship and Mechanisms

    PubMed Central

    Bale, Tracy L.; Epperson, C. Neill

    2015-01-01

    The British epidemiologist Dr. David J. Barker documented the relationship between infant birth weight and later onset of hypertension, coronary heart disease, insulin resistance, and type II diabetes. A stressful in utero environment can cause long-term consequences for offspring through prenatal programming. Prenatal programming most commonly occurs through epigenetic mechanisms and can be dependent on the type and timing of exposure as well as the sex of the fetus. In this review, we highlight the most recent evidence that prenatal programming is implicated in the development of psychiatric disorders in offspring exposed to maternal stress during pregnancy. Methodological differences between studies contribute to unavoidable heterogeneity in study findings. Current data suggest that fetal exposure to maternal hypothalamic-pituitary-adrenal axis dysregulation, excessive glucocorticoids, and inflammation with resulting epigenetic changes at both the placental and fetal levels are important areas of continued investigation. PMID:25617041

  1. A remarkable new genus and a new species of chewing louse (Phthiraptera, Ischnocera, Philopteridae) from Brazil

    PubMed Central

    Valim, Michel P.; Cicchino, Armando C.

    2015-01-01

    Abstract A new genus of chewing louse as Bobdalgleishia, and its type species Bobdalgleishia stephanophallus sp. n. (Phthiraptera) belonging to the Brueelia-complex (Ischnocera: Philopteridae) are described. Adults of the new species are fully described, illustrated and compared morphologically with the type species of Motmotnirmus Mey & Barker, 2014, which is its closest relative. The type host of Bobdalgleishia stephanophallus is a subspecies of the great jacamar Jacamerops aureus ridgwayi Todd, 1943, an endemic Amazonian bird distributed in northern Brazil, and the type locality is the State of Pará. Bobdalgleishia is a remarkable genus with unique morphological and chaetotaxic characters which readily separate it from other members of the Brueelia-complex, in particular by having the first two marginal temporal and ocular setae very long. PMID:26798280

  2. Thermodynamic properties of van der Waals fluids from Monte Carlo simulations and perturbative Monte Carlo theory

    NASA Astrophysics Data System (ADS)

    Díez, A.; Largo, J.; Solana, J. R.

    2006-08-01

    Computer simulations have been performed for fluids with van der Waals potential, that is, hard spheres with attractive inverse power tails, to determine the equation of state and the excess energy. On the other hand, the first- and second-order perturbative contributions to the energy and the zero- and first-order perturbative contributions to the compressibility factor have been determined too from Monte Carlo simulations performed on the reference hard-sphere system. The aim was to test the reliability of this "exact" perturbation theory. It has been found that the results obtained from the Monte Carlo perturbation theory for these two thermodynamic properties agree well with the direct Monte Carlo simulations. Moreover, it has been found that results from the Barker-Henderson [J. Chem. Phys. 47, 2856 (1967)] perturbation theory are in good agreement with those from the exact perturbation theory.

  3. Magnetic fields in noninvasive brain stimulation.

    PubMed

    Vidal-Dourado, Marcos; Conforto, Adriana Bastos; Caboclo, Luis Otávio Sales Ferreira; Scaff, Milberto; Guilhoto, Laura Maria de Figueiredo Ferreira; Yacubian, Elza Márcia Targas

    2014-04-01

    The idea that magnetic fields could be used therapeutically arose 2000 years ago. These therapeutic possibilities were expanded after the discovery of electromagnetic induction by the Englishman Michael Faraday and the American Joseph Henry. In 1896, Arsène d'Arsonval reported his experience with noninvasive brain magnetic stimulation to the scientific French community. In the second half of the 20th century, changing magnetic fields emerged as a noninvasive tool to study the nervous system and to modulate neural function. In 1985, Barker, Jalinous, and Freeston presented transcranial magnetic stimulation, a relatively focal and painless technique. Transcranial magnetic stimulation has been proposed as a clinical neurophysiology tool and as a potential adjuvant treatment for psychiatric and neurologic conditions. This article aims to contextualize the progress of use of magnetic fields in the history of neuroscience and medical sciences, until 1985.

  4. Phase-coded microwave signal generation based on a single electro-optical modulator and its application in accurate distance measurement.

    PubMed

    Zhang, Fangzheng; Ge, Xiaozhong; Gao, Bindong; Pan, Shilong

    2015-08-24

    A novel scheme for photonic generation of a phase-coded microwave signal is proposed and its application in one-dimension distance measurement is demonstrated. The proposed signal generator has a simple and compact structure based on a single dual-polarization modulator. Besides, the generated phase-coded signal is stable and free from the DC and low-frequency backgrounds. An experiment is carried out. A 2 Gb/s phase-coded signal at 20 GHz is successfully generated, and the recovered phase information agrees well with the input 13-bit Barker code. To further investigate the performance of the proposed signal generator, its application in one-dimension distance measurement is demonstrated. The measurement accuracy is less than 1.7 centimeters within a measurement range of ~2 meters. The experimental results can verify the feasibility of the proposed phase-coded microwave signal generator and also provide strong evidence to support its practical applications.

  5. Maternal preeclampsia and risk for cardiovascular disease in offspring.

    PubMed

    Herrera-Garcia, Guadalupe; Contag, Stephen

    2014-09-01

    Hypertensive disease of pregnancy (HDP) has been associated with elevated lifetime cardiovascular risk, including stroke, myocardial disease, coronary artery disease, and peripheral arterial disease. These two entities share common risk factors such as obesity, insulin resistance, diabetes, and hypertension. This article will evaluate the current literature on the maternal and fetal cardiovascular risks posed by HDP. The landmark study by Barker et al. demonstrated increased cardiovascular risk in growth-restricted infants, which may also be associated with HDP. Research has demonstrated the effects that HDP may have on the vascular and nephron development in offspring, particularly with respect to endothelial and inflammatory markers. In order to control for confounding variables and better understand the relationship between HDP and lifetime cardiovascular risk, future research will require following blood pressure and metabolic profiles of the parturients and their offspring.

  6. Perturbation theory for multicomponent fluids based on structural properties of hard-sphere chain mixtures

    SciTech Connect

    Hlushak, Stepan

    2015-09-28

    An analytical expression for the Laplace transform of the radial distribution function of a mixture of hard-sphere chains of arbitrary segment size and chain length is used to rigorously formulate the first-order Barker-Henderson perturbation theory for the contribution of the segment-segment dispersive interactions into thermodynamics of the Lennard-Jones chain mixtures. Based on this approximation, a simple variant of the statistical associating fluid theory is proposed and used to predict properties of several mixtures of chains of different lengths and segment sizes. The theory treats the dispersive interactions more rigorously than the conventional theories and provides means for more accurate description of dispersive interactions in the mixtures of highly asymmetric components.

  7. Acidic episodes and surface-water chemistry: a comparison of northeast and southeast study sites. Project report

    SciTech Connect

    Ford, D.E.; Malcom, J.T.; Murdoch, P.S.; Olem, H.; Witt, E.C.

    1987-05-01

    Much of the emphasis in the National Acid Precipitation Assessment Program (NAPAP) has been on historical or long-term trends in surface-water acidification. Short-term acidic episodes, however, also might have significant adverse effects on aquatic ecosystems. The U.S. EPA is presently designing an Episodic Response Project to investigate the regional extent, frequency, duration and magnitude of acidic episodes. The studies discussed in the report, however, were conducted under NAPAP Task Group E2-Aquatic Effects. A total of four episodic studies were conducted in the Catskill Mountains of New York (Murdoch, USGS), Laurel Hills, PA (Witt and Barker, USGS), Southern Blue Ridge Province, NC, TN (Olem, TVA), and Ouachita Mountains, AR (Nix et al., Ouachita Baptist University).

  8. (Research on Trichoderma cellulases)

    SciTech Connect

    Woodward, J.

    1989-09-29

    The traveler attended TRICEL 89, the first international symposium on Trichoderma cellulases. He presented a paper summarizing his work at ORNL. He also visited Aston University in Birmingham, England, and gave a lecture describing his work at Oak Ridge National Laboratory (ORNL). In Vienna, the latest knowledge concerning Trichoderma cellulases was obtained, and two contacts were established that will lead to unclassified and nonproprietary cooperative research efforts between ORNL and these European colleagues. In Birmingham, unclassified and nonproprietary discussions were held with Professor P.E. Barker and his staff in the Department of Chemical Engineering and Applied Chemistry. As a result of these discussions, areas of research cooperation between ORNL and Aston University were identified, and it is hoped that this cooperation will attract funding from the National Science Foundation (US) and the European Economic Community (EEC).

  9. Updates from the Fourth International Congress 'psoriasis: from gene to clinic', the Royal College of Physicians, London, UK, 1-3 December 2005.

    PubMed

    Camp, R D R

    2006-12-01

    The fourth 'Psoriasis: From Gene to Clinic' meeting was held in December 2005, its international status confirmed by the presence of almost 300 delegates from Europe, North America, Asia and Australasia. The meeting was co-organized by Jonathan Barker (St John's Institute of Dermatology, London) and Chris Griffiths (University of Manchester), who once again deserve congratulations for the success of their initiative. As its title suggests, the meeting was targeted at both clinical and basic scientists with a special interest in psoriasis, but in preparing this report the writer has selected presentations that caught his attention and that he felt able to review in a manner that might be of interest to the general readership of this Journal.

  10. Binary Pulse Compression Techniques for MST Radars

    NASA Technical Reports Server (NTRS)

    Woodman, R. F.; Sulzer, M. P.; Farley, D. T.

    1984-01-01

    In most mesosphere-stratosphere-troposphere (MST) applications pulsed radars are peak power limited and have excess average power capability. Short pulses are required for good range resolution but the problem of range biguity (signals received simultaneously from more than one altitude) sets a minimum limit on the interpulse period (IPP). Pulse compression is a echnique which allows more of the transmitter average power capacity to be used without scarificing range resolution. Binary phase coding methods for pulse compression are discussed. Many aspects of codes and decoding and their applications to MST experiments are addressed; this includes Barker codes and longer individual codes, and then complementary codes and other code sets. Software decoding, hardware decoders, and coherent integrators are also discussed.

  11. Diurnal behaviour of water on Mars

    NASA Technical Reports Server (NTRS)

    Flasar, F. M.; Goody, R. M.

    1976-01-01

    A numerical model of the diurnal transport of water across the Martian surface is developed. The atmospheric boundary layer is modeled in terms of local radiative-convective processes, and radiative effects of ice fogs near the surface are included. Diffusion of water in the ground is treated for the cases of adsorption and condensation. The model is applied to the diurnal variation of water vapor in the atmosphere as observed by Barker (1974). The morning rise in the amount of water vapor can be explained in terms of the evaporation of ground fogs. The evening decrease is compatible with the model if adsorption dominates in the soil. The average level of vapor concentration requires that the atmosphere above the boundary layer be relatively dry. The ground fogs persist until midmorning and should be observable. Some consequences of these conclusions are discussed.

  12. New signatures of underground nuclear tests revealed by satellite radar interferometry

    USGS Publications Warehouse

    Vincent, P.; Larsen, S.; Galloway, D.; Laczniak, R.J.; Walter, W.R.; Foxall, W.; Zucca, J.J.

    2003-01-01

    New observations of surface displacement caused by past underground nuclear tests at the Nevada Test Site (NTS) are presented using interferometric synthetic aperture radar (InSAR). The InSAR data reveal both coseismic and postseismic subsidence signals that extend one kilometer or more across regardless of whether or not a surface crater was formed from each test. While surface craters and other coseismic surface effects (ground cracks, etc.) may be detectable using high resolution optical or other remote sensing techniques, these broader, more subtle subsidence signals (one to several centimeters distributed over an area 1-2 kilometers across) are not detectable using other methods [Barker et al., 1998]. A time series of interferograms reveal that the postseismic signals develop and persist for months to years after the tests and that different rates and styles of deformation occur depending on the geologic and hydrologic setting and conditions of the local test area.

  13. First observation of a muscle spindle in fish.

    PubMed

    Maeda, N; Miyoshi, S; Toh, H

    1983-03-01

    In many groups of vertebrates, the muscle spindle is a specialized sensory organ for the detection of muscle stretching. The structure of the spindle varies among vertebrate classes. Moreover, Barker has asserted that Amphibia are the most primitive vertebrates to possess muscle spindles. Extensive studies, made mainly on the locomotor myotome, seem to show that the muscle receptors of fish are less specialized than those of more advanced animals, and that muscle spindles are absent. However, little attention has been paid to the jaw-closing muscle. We report here our finding of a very simple muscle spindle with a single intrafusal fibre in the well-developed jaw-closing muscle, adductor mandibulae, in a primitive teleostean, Oncorhynchus masou (Brevoort).

  14. An efficient method for unfolding kinetic pressure driven VISAR data

    SciTech Connect

    Mark Harry Hess; Peterson, Kyle; Harvey-Thompson, Adam James

    2015-08-18

    Velocity Interferometer System for Any Reflector (VISAR) [Barker and Hollenbach, J. Appl. Phys. 43, 4669 (1972)] is a well-known diagnostic that is employed on many shock physics and pulsed-power experiments. With the VISAR diagnostic, the velocity on the surface of any metal flyer can be found. For most experiments employing VISAR, either a kinetic pressure [Grady, Mech. Mater. 29, 181 (1998)] or a magnetic pressure [Lemke et al., Intl J. Impact Eng. 38, 480 (2011)] drives the motion of the flyer. Moreover, reliable prediction of the time-dependent pressure is often a critical component to understanding the physics of these experiments. Although VISAR can provide a precise measurement of a flyer’s surface velocity, the real challenge of this diagnostic implementation is using this velocity to unfold the time-dependent pressure. The purpose of this study is to elucidate a new method for quickly and reliably unfolding VISAR data.

  15. Midlatitude sporadic-E layers and vertical metallic ion drift profiles

    NASA Astrophysics Data System (ADS)

    Royrvik, O.

    1983-02-01

    An investigation of the relationship between the occurrence of midlatitude sporadic-E-layers and convergent points in the ion drift profiles has been made using the 430 MHz incoherent scatter radar at the Arecibo Observatory. Electron concentration profiles were obtained using a 13 baud Barker coded pulse yielding 600 m range resolution, while a 5-pulse sequence with 2.4 km range resolution was used to obtain line-of-sight ion drift velocities. With some exceptions, observed sporadic-E layers occur near convergent points in the vertical metallic ion drift profile, and vertical motions of these layers follow the vertical motions of the convergent point. A sudden increase in the altitude of a sporadic-E layer has been observed. This is attributed to the disappearance of the convergent point, releasing the layer, followed by an ascent of the layer to the closest overlying convergent point.

  16. The effect of high viscosity on the flow around a cylinder and around a sphere

    NASA Technical Reports Server (NTRS)

    Homann, F

    1952-01-01

    For the determination of the flow velocity one is accustomed to measure the impact pressure, i.e., the pressure intensity in front of an obstacle. In incompressible fluids the impact pressure is yv(sup 2)/2g if the influence of viscosity can be neglected. Such an influence is appreciable, however, when the Reynolds number corresponding to impact tube radius is under about 100, and must consequently be considered, if the velocity determination is not to be faulty. The first investigation of this influence are included in the work of Miss M. Barker. In the following pages, experiments will be reported which determine the intensity of impact pressure on cylinders and spheres; furthermore a theory of the phenomenon will be developed which is in good agreement with the measurements.

  17. HR 7578 - A K dwarf double-lined spectroscopic binary with peculiar abundances

    NASA Technical Reports Server (NTRS)

    Fekel, F. C., Jr.; Beavers, W. I.

    1983-01-01

    The number of double-lined K and M dwarf binaries which is currently known is quite small, only a dozen or less of each type. The HR 7578 system was classified as dK5 on the Mount Wilson system and as K2 V on the MK ystem. A summary of radial-velocity measurements including the observatory and weight of each observation is given in a table. The star with the stronger lines has been called component A. The final orbital element solution with all observations appropriately weighted was computed with a differential corrections computer program described by Barker et al. (1967). The program had been modified for the double-lined case. Of particular interest are the very large eccentricity of the system and the large minimum masses for each component. These large minimum masses suggest that eclipses may be detectable despite the relatively long period and small radii of the stars.

  18. Mercury emissions control by wet FGD systems: EPRI pilot-scale results

    SciTech Connect

    Peterson, J.R.; Hargrove, O.W. Jr.; Seeger, D.M.

    1995-06-01

    This paper presents results from pilot-scale tests that investigated mercury removal across wet limestone flue gas desulfurization (FGD) systems. The program was conducted at EPRIs Environmental Control Technology Center, located in Barker, NY. The test results showed that mercuric chloride (HgCl{sub 2}) was efficiently removed across the FGD system, while elemental mercury was not collected. The practical implication of this study is that although FGD systems efficiently remove some forms of mercury from flue gas, the overall mercury removal efficiency, and therefore the total mercury emissions from a coal-fired power plant equipped with an FGD system, will depend on the chemical form of the mercury in the flue gas. Unfortunately, no validated gas sampling method is available for speciating the different forms of mercury in flue gas. It is, therefore, difficult to predict mercury removal across FGD systems and to interpret any mercury removal data that have been collected.

  19. Shock Hugoniot of 1215 steel

    NASA Astrophysics Data System (ADS)

    Brar, N. S.; Rosenberg, Z.

    1996-05-01

    1215 steel is almost pure iron with 0.1 percent or less carbon. Information pertaining to deformation of this material under shock loading is useful to simulate penetration of projectiles of different shapes, such as fragments or rods, in propellants storage containments made from almost pure iron. In this paper we present the dynamic response of 1215 steel to shock wave loading to 30 GPa. Manganin gauges were used to record the stress wave profiles in these experiments. The Hugoniot data in the stress-particle velocity plane was obtained to 30 GPa. Hugoniot elastic limit was found to be 1.37±0.05 GPa. Phase transformation (α-ɛ) takes place at about 13.2±0.2 GPa, which agrees with the value determined by Barker and Hollenbach using VISAR. Hugoniot does not show any softening at stresses below 13 GPa.

  20. Dissociative adsorption of O2 on unreconstructed metal (100) surfaces: Pathways, energetics, and sticking kinetics

    SciTech Connect

    Liu, Da-Jiang; Evans, James W.

    2014-05-06

    An accurate description of oxygen dissociation pathways and kinetics for various local adlayer environments is key for an understanding not just of the coverage dependence of oxygen sticking, but also of reactive steady states in oxidation reactions. Density functional theory analysis for M(100) surfaces with M=Pd, Rh, and Ni, where O prefers the fourfold hollow adsorption site, does not support the traditional Brundle-Behm-Barker picture of dissociative adsorption onto second-nearest-neighbor hollow sites with an additional blocking constraint. Rather adsorption via neighboring vicinal bridge sites dominates, although other pathways can be active. The same conclusion also applies for M=Pt and Ir, where oxygen prefers the bridge adsorption site. Statistical mechanical analysis is performed based on kinetic Monte Carlo simulation of a multisite lattice-gas model consistent with our revised picture of adsorption. This analysis determines the coverage and temperature dependence of sticking for a realistic treatment of the oxygen adlayer structure.

  1. Investigation of Three-Dimensional (3-D) Solar Radiative Transfer Effects Using A-Train Satellite Measurements

    NASA Astrophysics Data System (ADS)

    Ham, S.; Kato, S.; Barker, H.; Rose, F. G.

    2012-12-01

    Three-dimensional (3-D) radiative effects are examined for cloudy atmosphere obtained from A-train satellite measurements. Since CloudSat and Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) only provide two-dimensional (2-D) nadir profiles along the satellite track, Moderate Resolution Imaging Spectroradiometer (MODIS) spectral radiances are used to extend the 2-D cloud profiles to the cross track direction (Barker et al., 2011). Then one-dimensional (1-D) and 3-D simulations are performed to get (SW) broad band (BB) flux and heating rate profile for constructed 3-D cloud field. In the simulation, correlated k-distribution model is employed to obtain rapid estimation of gaseous optical depths for 70 solar spectral bands. The difference between 1-D and 3-D results are interpreted as 3-D solar effects, and analyzed for different cloud types and solar zenith angle. In addition, modeled top-of-atmosphere (TOA) irradiances by the 1-D and 3-D models are compared to Clouds and the Earth's Radiant Energy System (CERES)-derived TOA irradiances. The preliminary results show that 3-D cloud absorption is larger than 1-D calculation, and thus 3-D heating rate is larger than 1-D heating rate for cloud layer. On the other hand, 3-D downward flux at surface is smaller than 1-D flux. Reference Barker, H. W., M. P. Jerg, T. Wehr, S. Kato, D. P. Donovan, and R. J. Hogan, 2011, A 3D cloud-construction algorithm for the EarthCARE mission, Q. J. R. Meteorol. Soc., 137, 1042-1058.

  2. Increasing average power in medical ultrasonic endoscope imaging system by coded excitation

    NASA Astrophysics Data System (ADS)

    Chen, Xiaodong; Zhou, Hao; Wen, Shijie; Yu, Daoyin

    2008-12-01

    Medical ultrasonic endoscope is the combination of electronic endoscope and ultrasonic sensor technology. Ultrasonic endoscope sends the ultrasonic probe into coelom through biopsy channel of electronic endoscope and rotates it by a micro pre-motor, which requires that the length of ultrasonic probe is no more than 14mm and the diameter is no more than 2.2mm. As a result, the ultrasonic excitation power is very low and it is difficult to obtain a sharp image. In order to increase the energy and SNR of ultrasonic signal, we introduce coded excitation into the ultrasonic imaging system, which is widely used in radar system. Coded excitation uses a long coded pulse to drive ultrasonic transducer, which can increase the average transmitting power accordingly. In this paper, in order to avoid the overlapping between adjacent echo, we used a four-figure Barker code to drive the ultrasonic transducer, which is modulated at the operating frequency of transducer to improve the emission efficiency. The implementation of coded excitation is closely associated with the transient operating characteristic of ultrasonic transducer. In this paper, the transient operating characteristic of ultrasonic transducer excited by a shock pulse δ(t) is firstly analyzed, and then the exciting pulse generated by special ultrasonic transmitting circuit composing of MD1211 and TC6320. In the final part of the paper, we designed an experiment to validate the coded excitation with transducer operating at 5MHz and a glass filled with ultrasonic coupling liquid as the object. Driven by a FPGA, the ultrasonic transmitting circuit output a four-figure Barker excitation pulse modulated at 5MHz, +/-20 voltage and is consistent with the transient operating characteristic of ultrasonic transducer after matched by matching circuit. The reflected echo from glass possesses coded character, which is identical with the simulating result by Matlab. Furthermore, the signal's amplitude is higher.

  3. Low birth weight: causes and consequences

    PubMed Central

    2013-01-01

    During our phylogenetic evolution we have selected genes, the so called thrifty genes, that can help to maximize the amount of energy stored from every consumed calorie. An imbalance in the amount of stored calories can lead to many diseases. In the early 80’s the distinguished English epidemiologist David Barker, formulated a hypothesis suggesting that many events that occur during the intrauterine life and early in infancy can influence the occurrence of many diseases that will develop in adulthood. This theory proposes that under-nutrition and other insult or adverse stimulus in utero and during infancy can permanently change the body’s structure, physiology and metabolism. The lasting or lifelong effects of under-nutrition will depend on the period in the development at which it occurs. The clues that led Barker to his conclusions started to be discovered when he was studying the temporal trends in the incidence of ischemic heart disease in England and Wales. Examining data found in The Hertfordshire records, collected in the beginning of the last century, he found that the rates of mortality by ischemic heart disease was much higher in children born in less affluent counties and mostly in those with low birth weight. After his initial findings a myriad of diseases have been found to be linked to low birth weight and under-nutrition in utero and in the neonatal period. These diseases were then nominated adult diseases with fetal origin. Epidemiological studies that led to these findings suggest that in utero and early postnatal life have critical importance for long-term programming of health and disease, opening unique chances for primary prevention of chronic diseases. PMID:24128325

  4. Screening of coeliac disease in undetected adults and patients diagnosed with irritable bowel syndrome in Riyadh, Saudi Arabia.

    PubMed

    Al-Ajlan, Abdulrahman S

    2016-07-01

    The present study is to determine the prevalence and implication of coeliac disease (CD) among adult Saudis and compared to those with diagnosed irritable bowel syndrome. This prospective study was conducted among 980 adults. Out of that, 482 subjects (staff and students of Riyadh Health Science College) were designated as control cohorts for undetected coeliac disease. Furthermore, another contingent of 498 subjects diagnosed with irritable bowel syndrome (IBS) at Prince Salman Hospital and Al-Iman General Hospital also constituted a segment of the overall initial 1020 subjects. Both cases and control were tested for serological markers of coeliac disease (tissues transglutaminase (tTGAs) and endomysial autoantibody (EMAs) and were confirmed by histopathology test. All the positive for cases of coeliac disease were screened for iron deficiency anaemia, Vitamin D deficiency, and osteoporosis and weight assessment. The percentage of coeliac disease in control subjects and patients diagnosed with irritable bowel syndrome (IBS) were found to be 1.9% and 9.6% respectively, about 38% of the total coeliac disease patients are among females of middle age (20-39-years) and 16% of the males in the same age range. Whereas, 20% and 25% of all coeliac disease cases with ages of 40-59 were remarked as females and males respectively. The identical nature and overlap of symptoms of the two conditions could possibly result in misdiagnosis of coeliac diseases or over-diagnosis of irritable bowel syndrome. The findings of the study might also give considerable implications of the disease in the nutritional level which is noticeable. PMID:27298578

  5. Active transport on disordered microtubule networks: the generalized random velocity model.

    PubMed

    Kahana, Aviv; Kenan, Gilad; Feingold, Mario; Elbaum, Michael; Granek, Rony

    2008-11-01

    The motion of small cargo particles on microtubules by means of motor proteins in disordered microtubule networks is investigated theoretically using both analytical tools and computer simulations. Different network topologies in two and three dimensions are considered, one of which has been recently studied experimentally by Salman [Biophys. J. 89, 2134 (2005)]. A generalization of the random velocity model is used to derive the mean-square displacement of the cargo particle. We find that all cases belong to the class of anomalous superdiffusion, which is sensitive mainly to the dimensionality of the network and only marginally to its topology. Yet in three dimensions the motion is very close to simple diffusion, with sublogarithmic corrections that depend on the network topology. When details of the thermal diffusion in the bulk solution are included, no significant change to the asymptotic time behavior is found. However, a small asymmetry in the mean microtubule polarity affects the corresponding long-time behavior. We also study a three-dimensional model of the microtubule network in living animal cells. Three first-passage-time problems of intracellular transport are simulated and analyzed for different motor processivities: (i) cargo that originates near the nucleus and has to reach the membrane, (ii) cargo that originates from the membrane and has to reach the nucleus, and (iii) cargo that leaves the nucleus and has to reach a specific target in the cytoplasm. We conclude that while a higher motor processivity increases the transport efficiency in cases (i) and (ii), in case (iii) it has the opposite effect. We conjecture that the balance between the different network tasks, as manifested in cases (i) and (ii) versus case (iii), may be the reason for the evolutionary choice of a finite motor processivity.

  6. Screening of coeliac disease in undetected adults and patients diagnosed with irritable bowel syndrome in Riyadh, Saudi Arabia.

    PubMed

    Al-Ajlan, Abdulrahman S

    2016-07-01

    The present study is to determine the prevalence and implication of coeliac disease (CD) among adult Saudis and compared to those with diagnosed irritable bowel syndrome. This prospective study was conducted among 980 adults. Out of that, 482 subjects (staff and students of Riyadh Health Science College) were designated as control cohorts for undetected coeliac disease. Furthermore, another contingent of 498 subjects diagnosed with irritable bowel syndrome (IBS) at Prince Salman Hospital and Al-Iman General Hospital also constituted a segment of the overall initial 1020 subjects. Both cases and control were tested for serological markers of coeliac disease (tissues transglutaminase (tTGAs) and endomysial autoantibody (EMAs) and were confirmed by histopathology test. All the positive for cases of coeliac disease were screened for iron deficiency anaemia, Vitamin D deficiency, and osteoporosis and weight assessment. The percentage of coeliac disease in control subjects and patients diagnosed with irritable bowel syndrome (IBS) were found to be 1.9% and 9.6% respectively, about 38% of the total coeliac disease patients are among females of middle age (20-39-years) and 16% of the males in the same age range. Whereas, 20% and 25% of all coeliac disease cases with ages of 40-59 were remarked as females and males respectively. The identical nature and overlap of symptoms of the two conditions could possibly result in misdiagnosis of coeliac diseases or over-diagnosis of irritable bowel syndrome. The findings of the study might also give considerable implications of the disease in the nutritional level which is noticeable.

  7. Interview: partnering with the industry: the Olympic laboratory model.

    PubMed

    Cowan, David A; Barker, Campbell P

    2012-07-01

    David A Cowan and Campbell P Barker speak to Ryan De Vooght-Johnson at Bioanalysis in May 2012 about the partnership between industry and academia for the setup and running of the doping-control laboratory for the London 2012 Olympic Games. David A Cowan is Director of the London 2012 anti-doping laboratory as well as Director of the King's College London Drug Control Centre, the UK's only WADA-accredited anti-doping laboratory, and Head of the Department of Forensic Science and Drug Monitoring. Cowan co-founded the Drug Control Centre in 1978 and became its Director in 1990. He has published extensively in the field of pharmaceutical analysis, especially as it relates to detecting drug administration in sport, and was awarded a personal chair in pharmaceutical toxicology in 1996. Cowan became Head of the Department of Forensic Science and Drug Monitoring at King's College London in 2002. He has served on a number of national and international committees, including the Council of Europe Working Party Investigating Drug Abuse in Sport that led to the first World Anti-Doping Convention, the Laboratory Representative on the International Olympic Committee's Medical Commission, and WADA's Laboratory Accreditation Subcommittee. He is a member of the Crippen Club for Distinguished Toxicologists. In 1998 he was awarded the IOC Trophy for Sport Ethics by the BOA. He was a founding member of the World Association of Anti-Doping Scientists and became its first President serving on its Executive Board between 2001 and 2004. He was a Visiting Laboratory Director at the Salt Lake City Winter Olympic Games 2002, where the first novel erythropoiesis-stimulating protein (NESP) positive was discovered. He was also a senior advisory scientist at both the Turin Winter Olympic Games in 2006 and the Beijing Olympic Games in 2008. He was also a member of the IOC Medical Commission for the Sydney Olympic Games in 2000 and the Vancouver Winter Olympic Games in 2010. The Drug Control

  8. Geochemistry of sedimentary-derived migmatite from NE Sardinia, Italy

    NASA Astrophysics Data System (ADS)

    Cruciani, Gabriele; Fancello, Dario; Franceschelli, Marcello; Scodina, Massimo

    2015-04-01

    In NE Sardinia at Porto Ottiolu, about 30 km south of Olbia (NE Sardinia), crops out a sequence of migmatized ortho and paragneiss, belonging to the Variscan basement's axial zone. Sedimentary-derived migmatite, which have a layered appearance in the field, were affected by three major variscan folding phase. D2, which is characterized by tight folds, is the most widespread deformation in the field. Leucosomes consists of discontinuous centimetre-thick, coarse-grained layers, that follow the S2 schistosity and are folded by D2 deformation phase. The contact with mesosome is sharp and sometimes marked by melanosome trails. They consist of quartz, plagioclase, very rare K-feldspar, muscovite, biotite, fibrolite, and rare kyanite. Plagioclase is unzoned oligoclase, though in some cases a thin albite rim is observed. Muscovite occurs as: i) single small- to medium-grained flakes enclosed in feldspar; ii) coarse grained crystals associated to biotite, fibrolite, and opaques, iii) in intergrowth with biotite to form thin elongated, slightly oriented trails, marking the faint foliation. Mesosomes are medium-grained, well foliated rocks, consisting of quartz, plagioclase muscovite, , biotite, fibrolite ± K-feldspar ± garnet. Fibrolite, muscovite and biotite are associated, to form strongly oriented, thick levels. Muscovite also occurs as unoriented crystals, showing quartz exsolutions and thin rims. A few mm-thick melanosome is usually present at the boundary between the leucosomes and mesosomes. Leucosomes are characterized by: SiO2: 75.4-77.9; Al2O3: 13.2-14.5; Fe2O3tot: 0.3-0.5; MgO: 0.1-0.2; CaO: 2.7- 3.7; Na2O: 3.9-4.6; K2O: 0.4-0.6 wt.%. An interesting feature is the relative high calcium content already described in other sedimentary-derived migmatite from Sardinia (Cruciani et al., 2008). In the normative Ab-An-Or diagram (Barker, 1979) the leucosomes plot at the boundary between trondhjemite/tonalite fields. All leucosomes are corundum normative and peraluminous

  9. Interview: partnering with the industry: the Olympic laboratory model.

    PubMed

    Cowan, David A; Barker, Campbell P

    2012-07-01

    David A Cowan and Campbell P Barker speak to Ryan De Vooght-Johnson at Bioanalysis in May 2012 about the partnership between industry and academia for the setup and running of the doping-control laboratory for the London 2012 Olympic Games. David A Cowan is Director of the London 2012 anti-doping laboratory as well as Director of the King's College London Drug Control Centre, the UK's only WADA-accredited anti-doping laboratory, and Head of the Department of Forensic Science and Drug Monitoring. Cowan co-founded the Drug Control Centre in 1978 and became its Director in 1990. He has published extensively in the field of pharmaceutical analysis, especially as it relates to detecting drug administration in sport, and was awarded a personal chair in pharmaceutical toxicology in 1996. Cowan became Head of the Department of Forensic Science and Drug Monitoring at King's College London in 2002. He has served on a number of national and international committees, including the Council of Europe Working Party Investigating Drug Abuse in Sport that led to the first World Anti-Doping Convention, the Laboratory Representative on the International Olympic Committee's Medical Commission, and WADA's Laboratory Accreditation Subcommittee. He is a member of the Crippen Club for Distinguished Toxicologists. In 1998 he was awarded the IOC Trophy for Sport Ethics by the BOA. He was a founding member of the World Association of Anti-Doping Scientists and became its first President serving on its Executive Board between 2001 and 2004. He was a Visiting Laboratory Director at the Salt Lake City Winter Olympic Games 2002, where the first novel erythropoiesis-stimulating protein (NESP) positive was discovered. He was also a senior advisory scientist at both the Turin Winter Olympic Games in 2006 and the Beijing Olympic Games in 2008. He was also a member of the IOC Medical Commission for the Sydney Olympic Games in 2000 and the Vancouver Winter Olympic Games in 2010. The Drug Control

  10. A 400-kyr record of millennial-scale carbonate preservation events in the Southern Ocean: Implications for Atlantic Meridional Overturning Circulation and atmospheric CO2

    NASA Astrophysics Data System (ADS)

    Hodell, D. A.; Vautravers, M. J.; Barker, S.; Charles, C.; Crowhurst, S.

    2014-12-01

    Hodell et al. (2001) suggested that carbonate preservation in the deep Cape Basin represented a qualitative, high-resolution record of the temporal evolution of the carbonate saturation state of the deep sea. The carbonate signal reflects both transient events in the redistribution of alkalinity and DIC in the deep ocean and steady-state mass balance processes. Here we re-analyzed the carbonate records of Sites 1089/TN057-21 using an Avaatech XRF core scanner and measured elemental variations at 2.5-mm resolution for the past 400 kyrs. Log Ca/Ti is highly correlated to weight percent carbonate content and other dissolution proxies and resolves millennial-scale events in carbonate preservation. A high-pass filter removes the low-frequency (orbital) variability in carbonate preservation, which is attributed mainly to steady-state mass balance processes. The high-frequency (suborbital) component reflects transient responses to the redistribution of carbonate ion that is related mainly to changing deep-water circulation. During the last glacial period, distinct millennial-scale increases in carbonate preservation in piston core TN057-21 occurred during times of enhanced Atlantic Meridional Overtunring Circulation (AMOC) (Barker et al., 2010; Barker and Diz, 2014), as supported by increases in benthic δ13C and less radiogenic ɛNd values. Carbonate preservation peaked particularly during long, warm interstadials in Greenland when a deep water mass with high carbonate ion concentration was formed in the North Atlantic. Export of NADW may have been greater than the Holocene during some of these events ("overshoots") and/or preformed carbonate ion concentrations in North Atlantic source areas may have been higher owing to lower atmospheric CO2 and less carbonate production in surface water. Each South Atlantic carbonate peak is associated with the start of Antarctic cooling and declining or leveling of atmospheric CO2, reflecting the signature of a thermal bipolar seesaw

  11. Generation of long prolate volumes of uniform magnetic field in cylindrical saddle-shaped coils

    NASA Astrophysics Data System (ADS)

    Dinale, Justin; Vrbancich, Julian

    2014-03-01

    We investigate the uniformity of the magnetic flux density (referred to as the field uniformity) within a series of coils designed to provide a prolate volume of field uniformity. Computational modelling of two cylindrical coil systems which have a sinusoidal current density distributed on the surface of the cylinder, shows the extent of prolate field uniformity along the cylindrical axis, with height and width of the magnetic volume limited by the radius of the cylinder. The first coil system consists of a cos θ coil--a series of saddle-shaped filament loops spaced uniformly with respect to cos θ on the curved cylindrical surface, where θ is the angle between the radius of the cylinder and the horizontal radial axis (assuming a horizontal cylinder). The second coil system, named the ‘ELFcage’ coil, consists of saddle-shaped filament loops spaced uniformly with respect to a fixed Δθ, on the cylindrical surface. The volume of field uniformity is also compared with volumes generated by circular Helmholtz and Barker coil designs. For coil diameters of 2 m, the Helmholtz and Barker coils generate a volume of field uniformity within 1% to 3% of the field at the centre that extends ˜0.8 m and ˜1.4 m respectively along the axis of symmetry. This compares to an extent of 3 m and 6 m for both the cos θ and ELFcage coils wound on a 2 m diameter cylinder (8 m length), for 1% and 3% field uniformity respectively. Importantly, the ELFcage coil shows significantly greater field uniformity along the radial axis compared to the cos θ coil. An array of triaxial magnetometers was used to measure the volume of field uniformity within the cos θ coil system, consisting of two sets of orthogonal cos θ windings to generate radial fields and a solenoid winding to generate an axial field. These measurements confirmed the results obtained from computational modelling. The cos θ coil system is currently in use for calibration of magnetometers and for measuring the magnetic

  12. Assimilation of DMSP/SSUSI UV data into IDA4D

    NASA Astrophysics Data System (ADS)

    Gelinas, L. J.; Bust, G. S.; Brinkman, D. G.; Straus, P. R.; Swartz, R. L.

    2014-12-01

    Ionospheric Data Assimilation Four-Dimensional (IDA4D) is a continuous-time, three-dimensional imaging algorithm that can produce 4D electron density specifications for various science investigations [e.g., Bust et al., 2007]. IDA4D is based on three-dimensional variational (3DVAR) data assimilation [Daley and Barker, 2001]. The algorithm combines various data sources and their associated error covariances with a background model (in this case the IRI) and its covariances to produce an ionospheric specification with formal uncertainties. IDA4D employs a Gauss- Markov Kalman filter technique similar to that used by operational assimilation models. The model can ingest a broad spectrum of data types that are either linearly or non-linearly related to electron density, including ground-based TEC, space-based TEC as measured by GPS occultation sensors and UV emissions associated with nightside recombination of O+. IDA4D has been undergoing testing at The Aerospace Corporation to determine its performance with respect to combinations of input data sets under different conditions (solar minimum, solar maximum, geomagnetic activity). The results presented here summarize the performance of IDA4D when UV data is ingested, both with and without additional TEC measurements. The UV data used in the study summarized here are 135.6 nm emissions measured the SSUSI instruments on F16 and F18 DMSP. We discuss the process by which UV data is ingested into IDA4D, including data binning, error estimation and correction of 135.6 nm contamination from mutual neutralization of O+ and O-. Model performance is then assessed using comparisons to various ground truth data, including ISR data, Jason VTEC, CNOF/S in-situ plasma density and ionosonde-derived NmF2 values. The results of this study show that UV data improves model performance, particularly when TEC data coverage is sparse. Bust, G. S., G. Crowley, T. W. Garner, T. L. Gaussiran II, R. W. Meggs, C. N. Mitchell, P. S. J. Spencer, P

  13. Liquid theory with high accuracy and broad applicability: Coupling parameter series expansion and non hard sphere perturbation strategy

    NASA Astrophysics Data System (ADS)

    Zhou, Shiqi

    2011-12-01

    Thermodynamic and structural properties of liquids are of fundamental interest in physics, chemistry, and biology, and perturbation approach has been fundamental to liquid theoretical approaches since the dawn of modern statistical mechanics and remains so to this day. Although thermodynamic perturbation theory (TPT) is widely used in the chemical physics community, one of the most popular versions of the TPT, i.e. Zwanzig (Zwanzig, R. W. J. Chem. Phys. 1954, 22, 1420-1426) 1st-order high temperature series expansion (HTSE) TPT and its 2nd-order counterpart under a macroscopic compressibility approximation of Barker-Henderson (Barker, J. A.; Henderson, D. J. Chem. Phys. 1967, 47, 2856-2861), have some serious shortcomings: (i) the nth-order term of the HTSE is involved with reference fluid distribution functions of order up to 2n, and the higher-order terms hence progressively become more complicated and numerically inaccessible; (ii) the performance of the HTSE rapidly deteriorates and the calculated results become even qualitatively incorrect as the temperature of interest decreases. This account deals with the developments that we have made over the last five years or so to advance a coupling parameter series expansion (CPSE) and a non hard sphere (HS) perturbation strategy that has scored some of its greatest successes in overcoming the above-mentioned difficulties. In this account (i) we expatiate on implementation details of our schemes: how input information indispensable to high-order truncation of the CPSE in both the HS and non HS perturbation schemes is calculated by an Ornstein-Zernike integral equation theory; how high-order thermodynamic quantities, such as critical parameters and excess constant volume heat capacity, are extracted from the resulting excess Helmholtz free energy with irregular and inevitable numerical errors; how to select reference potential in the non HS perturbation scheme. (ii) We give a quantitative analysis on why convergence

  14. Heavy metal content (Cd, Ni, Cr and Pb) in soil amendment with a low polluted biosolid

    NASA Astrophysics Data System (ADS)

    Gomez Lucas, Ignacio; Lag Brotons, Alfonso; Navarro-Pedreño, Jose; Belén Almendro-Candel, Maria; Jordán, Manuel M.; Bech, Jaume; Roca, Nuria

    2016-04-01

    The progressively higher water quality standards in Europe has led to the generation of large quantities of sewage sludge derived from wastewater treatment (Fytili and Zabaniotou 2008). Composting is an effective method to minimize these risks, as pathogens are biodegraded and heavy metals are stabilized as a result of organic matter transformations (Barker and Bryson 2002; Noble and Roberts 2004). Most of the studies about sewage sludge pollution are centred in medium and high polluted wastes. However, the aim of this study was to assess the effects on soil heavy metal content of a low polluted sewage sludge compost in order to identify an optimal application rate based in heavy metal concentration under a period of cultivation of a Mediterranean horticultural plant (Cynara carducnculus). The experiment was done between January to June: rainfall was 71 mm, the volume of water supplied every week was 10.5 mm, mean air temperatures was 14.2, 20.4 (maximum), and 9.2◦C (minimum). The soil was a clay-loam anthrosol (WRB 2006). The experimental plot (60 m2) was divided into five subplots with five treatments corresponding to 0, 2, 4, 6, and 8 kg compost/m2. Three top-soil (first 20 cm) samples from each treatment were taken (January, April and June) and these parameters were analysed: pH, electrical conductivity, organic matter and total content of heavy metals (microwave acid digestion followed by AAS-spectrometry determination). The results show that sewage sludge compost treatments increase the organic matter content and salinity (electrical conductivity of the soils) and diminish the pH. Cd and Ni total content in top-soil was affected and both slightly reduce their concentration. Pb and Cr show minor changes. In general, the application of this low polluted compost may affect the mobility of Cd and Ni due to the pH modification and the water added by irrigation along time but Pb and Cr remain their content in the top-soil. References Barker, A.V., and G.M. Bryson

  15. THE PLACENTA IS THE CENTER OF THE CHRONIC DISEASE UNIVERSE

    PubMed Central

    Thornburg, Kent L.; Marshall, Nicole

    2015-01-01

    Over the past quarter century it has become clear that adult onset chronic diseases like heart disease and type 2 diabetes have their roots in early development. The report by David Barker and colleagues showing an inverse relationship between birthweight and mortality from ischemic heart disease was the first clear-cut demonstration of fetal programming. Because fetal growth depends upon the placental capacity to transport nutrients from maternal blood, it has been a suspected causative agent since the original Barker reports. Epidemiological studies have shown that placental size and shape have powerful associations with offspring disease. More recent studies have shown that maternal phenotypic characteristics, such as body mass index and height, interact with placental size and shape to predict disease with much more precision than does birthweight alone. For example, among people in the Helsinki Birth Cohort, who were born during 1924–1944, the risk for acquiring colorectal cancer increased as the placental surface became longer and more oval. Among people in whom the difference between the length and breadth of the surface exceeded 6 cm, the hazard ratio for the cancer was 2.3 (95% CI 1.2–4.7, p=0.003) compared with those in whom there was no difference. Among Finnish men, the hazard ratio for coronary heart disease was 1.07 (1.02–1.13, P =0.01) per 1% increase in the placental weight/birthweight ratio. Thus, it appears that the ratio of birthweight to placental weight, known as placental efficiency, predicts cardiovascular risk as well. Babies born with placentas at the extremes of efficiency are more vulnerable for adult onset chronic diseases. Recent evidence suggests that placental growth patterns are sex specific. Boys’ placentas are, in general, more efficient than those made by girls. Another recent discovery is that the size, shape and efficiencies of the placenta can change over years of time with very narrow confidence limits. This suggests

  16. Polar Climate Connections of the Last Glacial Period

    NASA Astrophysics Data System (ADS)

    Yang, X.; Rial, J. A.

    2015-12-01

    Ever since the cross-core chronology became available, the connection between the Earth's polar regions - or the lack of such [Wunsch, 2003; 2006] - has been an on-going debate in the paleoclimate community. While the inverse relationship inferred from the bipolar seesaw model [Crowley, 1992] could not account for the difference in signal shape of the polar records, integration/differentiation (I/D) has been proposed as the linkage between them [Schmittner et al., 2003; Huybers, 2004; Roe and Steig, 2004; Schmittner et al., 2004]. Stoker and Johnsen [2003] have proposed a revised (thermal) bipolar seesaw model (TBS), demonstrating that the climate record from Antarctic is that of the Greenland convolved with an exponential decaying function, which represents the heat reservoir of the Southern Ocean. More recently, Rial [2012] has proposed phase synchronization (PS) as the polar climate connection from which polar climate records can be treated approximately as a Hilbert transform pair. All three models (I/D, TBS, and PS) have been used to reconstruct past climate of the north from the longer climate record of the south [Siddall et al., 2006; Barker et al., 2011; Oh et al., 2014]. However, no comparison has been made to test and analyze these models against one another for their performance and stabilities. Here we investigated the aforementioned models with polar climate data on the recent AICC2012 chronology to derive the similarities and differences among them in both time and frequency domains. Most importantly we discussed how such differences translate to the discrepancies in reconstructions of the northern climate and possible physical mechanism(s) of connection each model limits and allows. ReferencesBarker et al., 2011, Science, 334(6054), 347-351. Crowley, 1992, Paleoceanography, 7(4), 489-497. Huybers, 2004, QSR, 23(1-2), 207-210. Oh et al., 2014, QSR, 83, 129-142. Rial, 2012, Am J Sci, 312(4), 417-448. Roe & Steig, 2004, Journal of Climate, 17(10), 1929

  17. Long-wave phonons in ZnSe-BeSe mixed crystals: Raman scattering and percolation model

    NASA Astrophysics Data System (ADS)

    Pagès, O.; Ajjoun, M.; Tite, T.; Bormann, D.; Tournié, E.; Rustagi, K. C.

    2004-10-01

    We extend to longitudinal-optical (LO) phonons the percolation model set for the basic understanding of the atypical transverse-optical (TO) one-bond→two-mode behavior observed by Raman scattering in the Be-Se spectral range of the random Zn1-xBexSe alloy (0⩽x⩽1) , which opens the class of mixed crystals with contrast in the bond stiffness. The study is supported by contour modeling of the TO and LO Raman line shapes. This is achieved via application of the Hon and Faust treatment to a version of the modified-random-element-isodisplacement model generalized to multioscillators. While the TO signal clearly discriminates between Be-Se vibrations within the hard Be -rich region and the soft Zn -rich one, complexity arises in the LO symmetry due to vibration coupling via the 1ong-range longitudinal polarization field. In particular this generates a massive transfer of oscillator strength from the low-frequency (LO-) (hard, soft)-mixed mode to the high-frequency (LO+) one, which results in an apparent LO+ single-mode behavior. Moreover the contrasts between the Zn-Se and Be-Se bond lengths and bond stiffness are proposed to force a Verleur and Barker-like (VB) discrete multimode Raman response from each region. Accordingly LO- and LO+ intramode transfers of oscillator strength superimpose to the LO-→LO+ intermode one. This accounts for the spectacular distortions of the LO+ line shape. On the whole, the puzzling LO behavior can be regarded as the result of a cooperative phenomenon between two discrete assemblies of polar LO phonons, driven by the long-range longitudinal polarization field. Also, the Verleur and Barker description accounts for subtle unexplained behaviors in the TO symmetry. More generally it appears to provide a much attractive area for the discussion of the asymmetries of the TO and LO Raman line shapes in random alloys, as a possible alternative to the much debated spatial correlation model or to internal/external strain effects.

  18. Pulse compression using binary phase codes

    NASA Technical Reports Server (NTRS)

    Farley, D. T.

    1983-01-01

    In most MST applications pulsed radars are peak power limited and have excess average power capacity. Short pulses are required for good range resolution, but the problem of range ambiguity (signals received simultaneously from more than one altitude) sets a minimum limit on the interpulse period (IPP). Pulse compression is a technique which allows more of the transmitter average power capacity to be used without sacrificing range resolution. As the name implies, a pulse of power P and duration T is in a certain sense converted into one of power nP and duration T/n. In the frequency domain, compression involves manipulating the phases of the different frequency components of the pulse. One way to compress a pulse is via phase coding, especially binary phase coding, a technique which is particularly amenable to digital processing techniques. This method, which is used extensively in radar probing of the atmosphere and ionosphere is discussed. Barker codes, complementary and quasi-complementary code sets, and cyclic codes are addressed.

  19. From square-well to Janus: improved algorithm for integral equation theory and comparison with thermodynamic perturbation theory within the Kern-Frenkel model.

    PubMed

    Giacometti, Achille; Gögelein, Christoph; Lado, Fred; Sciortino, Francesco; Ferrari, Silvano; Pastore, Giorgio

    2014-03-01

    Building upon past work on the phase diagram of Janus fluids [F. Sciortino, A. Giacometti, and G. Pastore, Phys. Rev. Lett. 103, 237801 (2009)], we perform a detailed study of integral equation theory of the Kern-Frenkel potential with coverage that is tuned from the isotropic square-well fluid to the Janus limit. An improved algorithm for the reference hypernetted-chain (RHNC) equation for this problem is implemented that significantly extends the range of applicability of RHNC. Results for both structure and thermodynamics are presented and compared with numerical simulations. Unlike previous attempts, this algorithm is shown to be stable down to the Janus limit, thus paving the way for analyzing the frustration mechanism characteristic of the gas-liquid transition in the Janus system. The results are also compared with Barker-Henderson thermodynamic perturbation theory on the same model. We then discuss the pros and cons of both approaches within a unified treatment. On balance, RHNC integral equation theory, even with an isotropic hard-sphere reference system, is found to be a good compromise between accuracy of the results, computational effort, and uniform quality to tackle self-assembly processes in patchy colloids of complex nature. Further improvement in RHNC however clearly requires an anisotropic reference bridge function.

  20. On the molecular origin of high-pressure effects in nanoconfinement: The role of surface chemistry and roughness

    NASA Astrophysics Data System (ADS)

    Long, Yun; Palmer, Jeremy C.; Coasne, Benoit; Śliwinska-Bartkowiak, Małgorzata; Jackson, George; Müller, Erich A.; Gubbins, Keith E.

    2013-10-01

    Experiments and simulations both suggest that the pressure experienced by an adsorbed phase confined within a carbon nanoporous material can be several orders of magnitude larger than the bulk phase pressure in equilibrium with the system. To investigate this pressure enhancement, we report a molecular-simulation study of the pressure tensor of argon confined in slit-shaped nanopores with walls of various models, including carbon and silica materials. We show that the pressure is strongly enhanced by confinement, arising from the effect of strongly attractive wall forces; confinement within purely repulsive walls does not lead to such enhanced pressures. Simulations with both the Lennard-Jones and Barker-Fisher-Watts intermolecular potentials for argon-argon interactions give rise to similar results. We also show that an increase in the wall roughness significantly decreases the in-pore pressure due to its influence on the structure of the adsorbate. Finally, we demonstrate that the pressures calculated from the mechanical (direct pressure tensor calculations) and the thermodynamic (volume perturbation method) routes yield almost identical results, suggesting that both methods can be used to calculate the local pressure tensor components in the case of these planar geometries.

  1. Theoretical study on ThF+, a prospective system in search of time-reversal violation

    NASA Astrophysics Data System (ADS)

    Denis, Malika; Nørby, Morten S.; Jensen, Hans Jørgen Aa; Severo Pereira Gomes, André; Nayak, Malaya K.; Knecht, Stefan; Fleig, Timo

    2015-04-01

    The low-lying electronic states of ThF+, a possible candidate in the search for P- and T-violation, have been studied using high-level correlated relativistic ab initio multi-reference coupled-cluster and configuration interaction approaches. For the 3Δ state component with Ω = 1 (electron electric dipole moment ‘science state’) we obtain an effective electric field of {{E}eff}=35.2 GV c{{m}-1}, a P- and T-odd electron-nucleon interaction constant of {{W}P,T}=48.4 kHz, a magnetic hyperfine interaction constant of {{A}\\parallel }=1833 MHz for 229Th (I=5/2), and a very large molecular dipole moment of 4.03 D. The Ω = 1 state is found to be more than 300 cm-1 lower in energy than Ω ={{0}+} (1{{Σ }+}), challenging the state assignment from an earlier theoretical study on this species (Barker et al 2012 J. Chem. Phys. 136 104305).

  2. The Role of Clouds: An Introduction and Rapporteur Report

    NASA Astrophysics Data System (ADS)

    Taylor, Patrick C.

    2012-07-01

    This paper presents an overview of discussions during the Cloud's Role session at the Observing and Modelling Earth's Energy Flows Workshop. N. Loeb and B. Soden convened this session including 10 presentations by B. Stevens, B. Wielicki, G. Stephens, A. Clement, K. Sassen, D. Hartmann, T. Andrews, A. Del Genio, H. Barker, and M. Sugi addressing critical aspects of the role of clouds in modulating Earth energy flows. Presentation topics covered a diverse range of areas from cloud microphysics and dynamics, cloud radiative transfer, and the role of clouds in large-scale atmospheric circulations patterns in both observations and atmospheric models. The presentations and discussions, summarized below, are organized around several key questions raised during the session. (1) What is the best way to evaluate clouds in climate models? (2) How well do models need to represent clouds to be acceptable for making climate predictions? (3) What are the largest uncertainties in clouds? (4) How can these uncertainties be reduced? (5) What new observations are needed to address these problems? Answers to these critical questions are the topics of ongoing research and will guide the future direction of this area of research.

  3. Translationally invariant calculations of form factors, nucleon densities and momentum distributions for finite nuclei with short-range correlations included

    NASA Astrophysics Data System (ADS)

    Shebeko, A. V.; Grigorov, P. A.; Iurasov, V. S.

    2012-11-01

    Relying upon our previous treatment of the density matrices for nuclei (in general, nonrelativistic self-bound finite systems) we are studying a combined effect of center-of-mass motion and short-range nucleon-nucleon correlations on the nucleon density and momentum distributions in light nuclei (4He and 16O). Their intrinsic ground-state wave functions are constructed in the so-called fixed center-of-mass approximation, starting with mean-field Slater determinants modified by some correlator ( e.g., after Jastrow or Villars). We develop the formalism based upon the Cartesian or boson representation, in which the coordinate and momentum operators are linear combinations of the creation and annihilation operators for oscillatory quanta in the three different space directions, and get the own "Tassie-Barker" factors for each distribution and point out other model-independent results. After this separation of the center-of-mass motion effects we propose additional analytic means in order to simplify the subsequent calculations ( e.g., within the Jastrow approach or the unitary correlation operator method). The charge form factors, densities and momentum distributions of 4He and 16O evaluated by using the well-known cluster expansions are compared with data, our exact (numerical) results and microscopic calculations.

  4. Theoretical and numerical investigations of inverse patchy colloids in the fluid phase

    NASA Astrophysics Data System (ADS)

    Kalyuzhnyi, Yurij V.; Bianchi, Emanuela; Ferrari, Silvano; Kahl, Gerhard

    2015-03-01

    We investigate the structural and thermodynamic properties of a new class of patchy colloids, referred to as inverse patchy colloids (IPCs) in their fluid phase via both theoretical methods and simulations. IPCs are nano- or micro- meter sized particles with differently charged surface regions. We extend conventional integral equation schemes to this particular class of systems: our approach is based on the so-called multi-density Ornstein-Zernike equation, supplemented with the associative Percus-Yevick approximation (APY). To validate the accuracy of our framework, we compare the obtained results with data extracted from NpT and NVT Monte Carlo simulations. In addition, other theoretical approaches are used to calculate the properties of the system: the reference hypernetted-chain (RHNC) method and the Barker-Henderson thermodynamic perturbation theory. Both APY and RHNC frameworks provide accurate predictions for the pair distribution functions: APY results are in slightly better agreement with MC data, in particular at lower temperatures where the RHNC solution does not converge.

  5. Freeman Dyson and Gravitational Spin Precession

    NASA Astrophysics Data System (ADS)

    Hari Dass, N. D.

    2014-04-01

    In 1974 Hulse and Taylor1 discovered the binary pulsar. At that time Prof. Dyson was visiting the Max Planck Institute for Physics at Munich, where I was also working. He initiated a number of discussions on this object. During them it occurred to me that this system could be used to test Geodetic Precession in Einsteins theory, which, even after years of work by the Stanford gyroscope expt,2 had remained a challenge. I showed some preliminary calculations to Prof Dyson and he encouraged me to do a more refined job. To be applicable to the binary pulsar, one needed to generalise the general relativistic calculations to beyond the so called test particle assumption. Barker and O'Connell3 had obtained such a result from analysing the gravitational interactions of spin-1/2 Dirac fermions in linearized spin-2 theories of gravitation. With C. F. Cho I produced a purely classical calculation, using Schwingers Source theory.4 Börner, Ehlers and Rudolf confirmed this result with their general relativistic calculations shortly after.5 With V. Radhakrishnan, I gave a detailed model for the pulse width and polarization sweep as a means of observing this effect.6-9 All throughout Prof. Dyson was supportive with reading the manuscripts and his critical comments. In 2005, coincidentally the centennial of the Annus Mirabilis (1905), Hotan, Bailes and Ord observed this in the binary pulsar J1141-6545.10

  6. Bonding at the Extreme. Detection and Characterization of Thorium Dimer, Th_2

    NASA Astrophysics Data System (ADS)

    Steimle, Timothy; Muscarella, Seth; Kokkin, Damian L.

    2015-06-01

    Due to the difficultly of working with actinides (radioactive, short lifetimes) and the number of electrons in these systems our chemical understanding either experimentally or theoretically on these systems is very limited. The electronic spectrum of thorium dimer, Th_2, is expected to be heavily congested due to the predicted twelve electronic states within an energy less then 1 eV of the calculated ^3Δ_g ground state. The chemical bond is predicted to be a quadruple bond in both the ground state and low lying ^1σ^+_g state (T_e=400 cm-1). Experimentally Th_2 was been detected in the gas phase by mass spectrometry. Here we report on the detection of the gas fluorescence spectrum of Th_2 in the 495-560 nm range via application of 2D LIF spectroscopy and attempts to record high resolution field free and Zeeman spectra. B.J. Roos, P.-Å. Malmqvist and L. Gagliardi, J. Am. Chem. Soc. 128, 17000-17006, 2006 M.C. Heaven, B.J. Barker and I.O. Antonov, J. Phys. Chem A. 118, 10867-10881, 2014

  7. New Benthic δ18o Stacks and Age Models for the Last Glacial Cycle (0-150 kyr ago)

    NASA Astrophysics Data System (ADS)

    Lisiecki, L. E.; Stern, J. V.

    2014-12-01

    The δ18O of formainiferal calcite is a common paleoceanographic proxy, which measures ice volume and deep water temperature change. Foraminiferal δ18O is also often used to create marine sediment core age models by aligning down-core variations in δ18O to a global stack, or average. However, the most commonly used stack, known as "LR04," has an outdated age model, assumes global benthic δ18O synchrony, and is biased to the Atlantic [Lisiecki and Raymo, 2005]. Here we present six regional benthic δ18O stacks of the last glacial cycle (0-150 kyr) that are combined to form a volume-weighted global stack with data from 263 sites. We develop new benthic δ18O age models using regional radiocarbon dates from 0-40 ka and correlations to the GICC05 layer-counted Greenland age model from 40-56 ka [Svensson et al., 2008] and U-Th-dated Chinese speleothems from 56-150 kyr [Wang et al., 2001; Cheng et al., 2009; Barker et al, 2011]. Additional features of the new stacks are diachronous benthic δ18O changes during the last two glacial terminations and explicit age uncertainty estimates throughout. Our new global stack indicates that some portions of the LR04 stack are up to 4 kyr too young. We estimate corrections to the LR04 age model throughout the Pleistocene that imply faster climate responses to orbital forcing than previously estimated.

  8. WRFDA 2012 Overview

    NASA Astrophysics Data System (ADS)

    Huang, X.-Y.

    2012-04-01

    WRFDA - the Weather Research and Forecasting (WRF) Data Assimilation system is a component of the WRF modeling system developed at the National Center for Atmospheric Research. WRFDA is an advanced data assimilation system, contained with the WRF software that provides state-of-art 3D/4D variational (3D/4D-Var) and variational/ensemble hybrid techniques (Barker et al. 2004; Huang et al. 2009; Wang et al. 2008). WRFDA is used in both applied and research settings. It is used as the analysis component of several international operational data assimilation systems (e.g. AFWA, CWB, KMA, BMB, UAE). It is also used by operational centers, as well as by universities and research institutions, for data assimilation research. WRFDA is a community data assimilation asset. NCAR maintains and develops the WRFDA website [http://www.mmm.ucar.edu/wrf/users/wrfda], where community users can browse, or download WRFDA documentation, tutorials and test data; participate in user forums and obtain the latest code. In this presentation, I will give a brief description of the current WRFDA status and present a recent WRFDA adjoint-based observation impact study.

  9. Vibronic Perturbations in the Electronic Spectrum of MgC

    NASA Astrophysics Data System (ADS)

    Lolur, Phalgun; Dawes, Richard; Heaven, Michael

    2014-06-01

    Accurate studies of the ground and low lying excited triplet pi-states of the covalently bonded alkaline earth metal carbides have been of interest to both theoreticians and experimentalists in the past few decades to understand their bonding. Diatomic beryllium carbide (BeC), which is valence iso-electronic with MgC, was probed by laser ablation and jet cooling techniques producing rotationally resolved data reported in a previous study.[1] Dynamically weighted MRCI calculations were used to construct adiabatic potential energy curves for the ground and the four lowest triplet pi-states up to 50,000 wn. From these, diabatic potentials and couplings were obtained and used to compute vibronic levels for the four interacting states. Here we apply the same methodology to MgC and examine the similarities and differences between the two systems. Results show significantly different bonding characteristics for the pi-states of MgC when compared to BeC. References: 1- B. J. Barker et al. J. Chem. Phys. 137, 214313 (2012).

  10. From square-well to Janus: Improved algorithm for integral equation theory and comparison with thermodynamic perturbation theory within the Kern-Frenkel model

    NASA Astrophysics Data System (ADS)

    Giacometti, Achille; Gögelein, Christoph; Lado, Fred; Sciortino, Francesco; Ferrari, Silvano; Pastore, Giorgio

    2014-03-01

    Building upon past work on the phase diagram of Janus fluids [F. Sciortino, A. Giacometti, and G. Pastore, Phys. Rev. Lett. 103, 237801 (2009)], we perform a detailed study of integral equation theory of the Kern-Frenkel potential with coverage that is tuned from the isotropic square-well fluid to the Janus limit. An improved algorithm for the reference hypernetted-chain (RHNC) equation for this problem is implemented that significantly extends the range of applicability of RHNC. Results for both structure and thermodynamics are presented and compared with numerical simulations. Unlike previous attempts, this algorithm is shown to be stable down to the Janus limit, thus paving the way for analyzing the frustration mechanism characteristic of the gas-liquid transition in the Janus system. The results are also compared with Barker-Henderson thermodynamic perturbation theory on the same model. We then discuss the pros and cons of both approaches within a unified treatment. On balance, RHNC integral equation theory, even with an isotropic hard-sphere reference system, is found to be a good compromise between accuracy of the results, computational effort, and uniform quality to tackle self-assembly processes in patchy colloids of complex nature. Further improvement in RHNC however clearly requires an anisotropic reference bridge function.

  11. Evaluation of a High-Resolution Regional Climate Ensemble

    NASA Astrophysics Data System (ADS)

    Bruyere, C. L.; Tye, M. R.; Keellings, D.; Jaye, A.

    2014-12-01

    A high-resolution Regional Climate Ensemble is used to investigate the limits of predictability of climate simulations, with a focus on high-impact weather. A diverse set of approaches are being applied to examine the impact of the different physics parameterizations on the simulated climate and high-impact weather statistics and to determine the physics combinations that result in realistic scenarios. In this paper we focus on the ensemble members' ability to correctly simulate current climate variability in terms of: 1) extreme temperature and precipitation over different regions, and 2) tropical cyclone statistics. A twenty-four member physics ensemble of climate simulations has been generated using the state-of-the-art Weather Research and Forecasting Model (Skamarock et al. 2008). The ensemble model has been run over an extended North American domain of approximately 25° S to 70° N and from the African coast to the East Pacific, and at sufficient resolution to capture high-impact weather events. Skamarock, W., J. B. Klemp, J. Dudhia, D. O. Gill, D. Barker, M. G. Duda, X. Huang, and W. Wang, 2008: A Description of the Advanced Research WRF Version 3. NCAR Technical Note NCAR/TN-475+STR. Boulder, CO.

  12. Super-resolution processing for multi-functional LPI waveforms

    NASA Astrophysics Data System (ADS)

    Li, Zhengzheng; Zhang, Yan; Wang, Shang; Cai, Jingxiao

    2014-05-01

    Super-resolution (SR) is a radar processing technique closely related to the pulse compression (or correlation receiver). There are many super-resolution algorithms developed for the improved range resolution and reduced sidelobe contaminations. Traditionally, the waveforms used for the SR have been either phase-coding (such as LKP3 code, Barker code) or the frequency modulation (chirp, or nonlinear frequency modulation). There are, however, an important class of waveforms which are either random in nature (such as random noise waveform), or randomly modulated for multiple function operations (such as the ADS-B radar signals in [1]). These waveforms have the advantages of low-probability-of-intercept (LPI). If the existing SR techniques can be applied to these waveforms, there will be much more flexibility for using these waveforms in actual sensing missions. Also, SR usually has great advantage that the final output (as estimation of ground truth) is largely independent of the waveform. Such benefits are attractive to many important primary radar applications. In this paper the general introduction of the SR algorithms are provided first, and some implementation considerations are discussed. The selected algorithms are applied to the typical LPI waveforms, and the results are discussed. It is observed that SR algorithms can be reliably used for LPI waveforms, on the other hand, practical considerations should be kept in mind in order to obtain the optimal estimation results.

  13. Experimental and Theoretical Studies of the Pure Rotational Spectra of Lead Halides: PbF and PbCl

    NASA Astrophysics Data System (ADS)

    Norman, Spencer; Dawes, Richard; Grubbs, G. S., II; Cooke, S. A.; Long, B. E.; Dewberry, Chris

    2014-06-01

    The pure rotational spectrum of lead monochloride, PbCl, has been measured and analyzed using chirped pulse and cavity Fourier transform microwave (CP-FTMW and FTMW) spectrometers equipped with an ablation source. Refined parameters of an effective Hamiltonian including fine and hyperfine interactions similar to those previously reported by Fink et al. [1] were determined. Dynamically-weighted, explicitly-correlated MRCI-F12 calculations [2] were performed for both PbF and the valence isoelectronic PbCl to predict potential energy curves (PEC). Spin-orbit coupling was included in the calculations, which is known to split the X12Π1/2 and X22Π3/2 components of the ground electronic state by roughly 8280 wn in both lead halide systems. Calculated rotational levels were obtained using the PECs and compared with experiment including previously published results for PbF [3]. References: 1- K. Ziebarth, K. D. Setzer, O. Shestakov,1 and E. H. Fink, J. Mol. Spec. 191, 108 (1998). 2- B. J. Barker et al. J. Chem. Phys. 137, 214313 (2012). 3- R. J. Mawhorter et al. Phys. Rev. A 84, 022508 (2011).

  14. The X-linked inhibitor of apoptosis regulates long-term depression and learning rate.

    PubMed

    Gibon, Julien; Unsain, Nicolas; Gamache, Karine; Thomas, Rhalena A; De Leon, Andres; Johnstone, Aaron; Nader, Karim; Séguéla, Philippe; Barker, Philip A

    2016-09-01

    Hippocampal long-term depression (LTD) is an active form of synaptic plasticity that is necessary for consolidation of spatial memory, contextual fear memory, and novelty acquisition. Recent studies have shown that caspases (CASPs) play an important role in NMDA receptor-dependent LTD and are involved in postsynaptic remodeling and synaptic maturation. In the present study, we examined the role of X-linked inhibitor of apoptosis (XIAP), a putative endogenous CASP inhibitor, in synaptic plasticity in the hippocampus. Analysis in acute brain slices and in cultured hippocampal neurons revealed that XIAP deletion increases CASP-3 activity, enhances α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor internalization, sharply increases LTD, and significantly reduces synapse density. In vivo behaviors related to memory were also altered in XIAP(-/-) mice, with faster acquisition of spatial object location and increased fear memory observed. Together, these results indicate that XIAP plays an important physiologic role in regulating sublethal CASP-3 activity within central neurons and thereby facilitates synaptic plasticity and memory acquisition.-Gibon, J., Unsain, N., Gamache, K., Thomas, R. A., De Leon, A., Johnstone, A., Nader, K., Séguéla, P., Barker, P. A. The X-linked inhibitor of apoptosis regulates long-term depression and learning rate.

  15. Evaluation of a Regional Climate Ensemble using Self-Organizing Maps

    NASA Astrophysics Data System (ADS)

    Jaye, A.; Bruyere, C. L.; Seefeldt, M. W.

    2014-12-01

    A Regional Climate Ensemble is used to investigate the limits of predictability of climate simulations, with a focus on high-impact weather. A twenty-four member physics ensemble of climate simulations using the state-of-the-art Weather Research and Forecasting Model at sufficient resolution to capture high-impact weather has been run over an extended North American domain of approximately 25° S to 70° N and from the African coast to the East Pacific. A diverse set of approaches are being applied to examine the impact of the different physics parameterizations on the simulated climate and high-impact weather statistics and to determine the physics combinations that result in physically realistic scenarios. In this paper we explore one such approach that evaluates the performance of the ensemble using Self-Organizing Maps (SOMs). The SOMs are used to: 1) identify the ensemble members that are able to capture current climate weather patterns and their relative frequencies, and 2) investigate the underlying interactions between the different physics components that leads to differences in these patterns across the ensemble. Results will be used to inform selection of ensemble members for future climate change impact studies. Skamarock, W., J. B. Klemp, J. Dudhia, D. O. Gill, D. Barker, M. G. Duda, X. Huang, and W. Wang, 2008: A Description of the Advanced Research WRF Version 3. NCAR Technical Note NCAR/TN-475+STR. Boulder, CO.

  16. Numerical modeling of the hydraulic signatures of horizontal and inclined faults

    NASA Astrophysics Data System (ADS)

    Rafini, Silvain; Larocque, Marie

    2012-03-01

    Pumping tests in discontinuous media are commonly interpreted using radial/non-radial flow analytical models, which do not account for a large range of multistage real signatures that combine both flow types. The term radial is employed in Barker's sense, referring to the cross-flow area growth with a flow dimension ( n) equal to 2, while multistage refers to a flow response of several time periods with successive n values. Synthetic domains are used to numerically investigate the flow behaviour of faulted media, specifically the effect of fault inclination on multistage signatures. Simulations are performed using single faults surrounded by a permeable matrix to characterize drawdown series and to identify hydrodynamic scenarios associated with some diagnostic multistage n sequences. The n sequence 2 - < 2 - 2 results from interactions between the matrix and a horizontal to weakly inclined fault, while 2 - 1.5 - 2 corresponds to a higher fault inclination and is a combination of the generalized horizontally and vertically faulted models. These results improve the interpretation of ambiguous drawdown series from long-term pumping tests. This provides a better hydraulic characterization of faulted environments, allowing assessment of fault and matrix properties such as fault inclination. The approach is successfully tested on real datasets.

  17. Pulse compression techniques to improve modulated pulsed laser line scan systems

    NASA Astrophysics Data System (ADS)

    Lee, Robert W.; Nash, Justin K.; Cochenour, Brandon M.; Mullen, Linda J.

    2015-05-01

    A modulated pulse laser imaging system has been developed which utilizes coded/chirped RF modulation to mitigate the adverse effects of optical scattering in degraded visual underwater environments. Current laser imaging techniques employ either short pulses or single frequency modulated pulses to obtain both intensity and range images. Systems using short pulses have high range resolution but are susceptible to scattering due to the wide bandwidth nature of the pulse. Range gating can be used to limit the effects of backscatter, but this can lead to blind spots in the range image. Modulated pulse systems can help suppress the contribution from scattered light in generated imagery without gating the receiver. However, the use of narrowband, single tone modulation results in limited range resolution where small targets are camouflaged within the background. This drives the need for systems which have high range resolution while still suppressing the effects of scattering caused by the environment. Coded/chirped modulated pulses enable the use of radar pulse compression techniques to substantially increase range resolution while also providing a way to discriminate the object of interest from the light scattered from the environment. Linearly frequency chirped waveforms and phase shift keyed barker codes were experimentally investigated to determine the effects that pulse compression would have on intensity/range data. The effect of modulation frequency on the data produced with both wideband and narrowband modulation was also investigated. The results from laboratory experiments will be presented and compared to model predictions.

  18. Purine metabolism by Methanococcus vannielii

    SciTech Connect

    DeMoll, E.; Tsai, L.

    1986-05-01

    During studies of biosynthesis of novel cofactors in Methanococcus vannielii, it was discovered that guanine and xanthine are degraded by extracts of this organism. Using labeled substrates it was shown that uric acid, guanine, and hypoxanthine are converted to xanthine, which is then degraded in a manner similar to that described by Rabinowitz and Barker for clostridia. Extracts of M. vannielii convert the 2-, 6-, and 8-carbon atoms of xanthine to CO/sub 2/. It appears that the 8-carbon is initially lost as formate, which is then oxidized to CO/sub 2/ by the endogenous formate dehydrogenase. Enzyme preparations exposed to oxygen failed to convert (/sup 14/C)xanthine or (/sup 14/C)guanine either to CO/sub 2/ or to a form not adsorbed to charcoal. This oxygen inhibition could be reversed by treatment with dithiothreitol. Extracts exposed to oxygen apparently fail to carry out the initial step in xanthine degradation. The overall reaction for the degradation of guanine or xanthine is inhibited by EDTA and this inhibition is reversed by supplements of Mn/sup 2 +/ or Fe/sup 2 +/. Based on these studies, it was shown that uric acid, guanine, hypoxanthine, or xanthine could serve as sole nitrogen source for growth of the organism.

  19. Neurofibromatosis and lessons for the war on cancer.

    PubMed

    Reilly, Karlyne M

    2009-07-01

    In the war on cancer, a great deal of attention is being paid to knowing the 'enemy'. It is widely believed that by understanding the driving forces underlying cancer, researchers can develop better ways to target the disease. Currently, large-scale efforts have been under taken to completely characterize molecular changes in common human cancers (http://cancergenome.nih.gov/) (Collins & Barker, 2007). However, as more is learned about cancer, the debate increases on what exactly the enemy is: cells making up the bulk of the tumour, rare tumour stem cells that can regrow the tumour, tumour microenvironment, the subset of cancer cells with metastatic potential, etc. Studies of the cancers associated with Neurofibromatosis type 1 (NF1) are helping to define the relationship between many of these different cell types. It is still unclear how these different enemies are related to each other and how they interact to wage cancer's war on the patient. 'If you know the enemy and know yourself you need not fear the results of a hundred battles.' - Sun Tzu, The Art of War, c. 500 B.C.

  20. The pancreatic beta cell as a paradigm for advances in inositide research.

    PubMed

    Barker, Christopher J; Berggren, Per-Olof

    2012-09-01

    In a previous review for Advances in Enzyme Research (Berggren and Barker, 2008) we outlined the history of our involvement in discovering important roles for inositides in the insulin secreting pancreatic beta cell. In this current appraisal we bring the work up to date and project how we believe this field will continue to develop in the future. Recently, we have seen an important synergism between the growth in our understanding of inositide function and our knowledge of beta cell stimulus-secretion coupling in both physiological and pathophysiological contexts. Important advances have been made in three areas. 1. The classic regulation of cytoplasmic free Ca(2+) concentration [Ca(2+)](i) by Inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) and its receptor, 2. A novel role of the inositol pyrophosphates, especially 5-diphosphoinositol pentakisphosphate (5-PP-InsP(5)), in exocytosis, and 3. The unique signaling roles of PI3K pathways instituted by the engagement of the insulin receptor in an autocrine, positive feed-back loop. We examine each of these in turn and close with an assessment of the likely future directions the research will take.

  1. The role of maternal nutrition, metabolic function and the placenta in developmental programming of renal dysfunction.

    PubMed

    Richter, V F I; Briffa, J F; Moritz, K M; Wlodek, M E; Hryciw, D H

    2016-01-01

    The intrauterine environment is critical for the development of the foetus. Barker and colleagues were the first to identify that adverse perturbations during foetal development are associated with an increased risk of developing diseases in adulthood, including cardiorenal disease. Specifically for the kidney, perturbations in utero can lead to nephron deficits and renal dysfunction by a number of mechanisms. Altered programming of nephron number is associated with an increased risk of developing kidney disease via glomerular hypertrophy and reduced vasodilative capacity of the renal blood vessels; both of which would contribute to hypertension in adulthood, with males being more susceptible to disease outcomes. Additionally, alterations in the renin-angiotensin system (RAS) such as an upregulation or downregulation of specific receptors, depending on the nature of the insult, have also been implicated in the development of renal dysfunction. Sex-specific differences in the expression of the RAS during late gestation and in the early postnatal environment have also been identified. Extensive research has demonstrated that both uteroplacental insufficiency and maternal malnutrition alter renal development in utero. Equally, exposure to maternal diabetes and maternal obesity during development are also associated with an increased risk of developing renal disease, however, the mechanism behind this association is poorly understood. Therefore, identifying the link between an adverse intrauterine environment and the programmed kidney disease risk in adulthood may facilitate the development of strategies to alleviate the epidemics of cardiorenal disease worldwide, in addition to understanding why males are more susceptible to adult-onset cardiovascular diseases.

  2. Automated cleaning of foraminifera shells before Mg/Ca analysis using a pipette robot

    NASA Astrophysics Data System (ADS)

    Johnstone, Heather J. H.; Steinke, Stephan; Kuhnert, Henning; Bickert, Torsten; Pälike, Heiko; Mohtadi, Mahyar

    2016-08-01

    The molar ratio of magnesium to calcium (Mg/Ca) in foraminiferal calcite is a widely used proxy for reconstructing past seawater temperatures. Thorough cleaning of tests is required before analysis to remove contaminant phases such as clay and organic matter. We have adapted a commercial pipette robot to automate an established cleaning procedure, the "Mg-cleaning" protocol of Barker et al. (2003). Efficiency of the automated nine-step method was assessed through monitoring Al/Ca of trial samples (GeoB4420-2 core catcher). Planktonic foraminifera Globigerinoides ruber, Globigerinoides sacculifer, and Neogloboquadrina dutertrei from this sample gave Mg/Ca consistent with the habitat range of the three species, and 40-60% sample recovery after cleaning. Comparison between manually cleaned and robot-cleaned samples of G. ruber (white) from a sediment core (GeoB16602) showed good correspondence between the two methods for Mg/Ca (r = 0.93, p < 0001, n = 27). Average Al/Ca in robot-cleaned samples was 0.05 mmol/mol, showing that the samples are cleaned effectively by the robot. The robot offers increased sample throughput as batch sizes of up to 88 samples/blanks can be processed in ˜7 h with little intervention.

  3. Entangled lives: Implications of the developmental origins of health and disease hypothesis for bioarchaeology and the life course.

    PubMed

    Gowland, Rebecca L

    2015-12-01

    Epidemiological research since the 1980s has highlighted the consequences of early life adversity, particularly during gestation and early infancy, for adult health (the "Barker hypothesis"). The fast-evolving field of molecular epigenetics is providing explanatory mechanisms concerning phenotypic plasticity in response to developmental stressors and the accumulation of disease risk throughout life. In addition, there is now evidence for the heritability of poor health across generations via epigenetic modifications. This research has the potential to invoke a paradigmatic shift in how we interpret factors such as growth insults and immune response in past skeletal remains. It demonstrates that health cannot be understood in terms of immediate environmental circumstances alone. Furthermore, it requires both a theoretical and practical re-evaluation of disease biographies and the life course more generally. Individual life courses can no longer be regarded as discrete, bounded, life histories, with clearly defined beginning and end points. If socioeconomic circumstances can have intergenerational effects, including disease susceptibility and growth stunting, then individual biographies should be viewed as nested or "embedded" within the lives of others. This commingling of life courses may prove problematic to unravel; nevertheless, this review aims to consider the potential consequences for bioarchaeological interpretations. These include a greater consideration of: the temporal power of human skeletons and a life course approach to past health; infant health and the implications for maternal well-being; and the impact of non-proximate stressors (e.g., early life and ancestral environments) on the presence of health indicators.

  4. Infants in cocktail parties

    NASA Astrophysics Data System (ADS)

    Newman, Rochelle S.

    2003-04-01

    Most work on listeners' ability to separate streams of speech has focused on adults. Yet infants also find themselves in noisy environments. In order to learn from their caregivers' speech in these settings, they must first separate it from background noise such as that from television shows and siblings. Previous work has found that 7.5-month-old infants can separate streams of speech when the target voice is more intense than the distractor voice (Newman and Jusczyk, 1996), when the target voice is known to the infant (Barker and Newman, 2000) or when infants are presented with an audiovisual (rather than auditory-only) signal (Hollich, Jusczyk, and Newman, 2001). Unfortunately, the paradigm in these studies can only be used on infants at least 7.5 months of age, limiting the ability to investigate how stream segregation develops over time. The present work uses a new paradigm to explore younger infants' ability to separate streams of speech. Infants aged 4.5 months heard a female talker repeat either their own name or another infants' name, while several other voices spoke fluently in the background. We present data on infants' ability to recognize their own name in this cocktail party situation. [Work supported by NSF and NICHD.

  5. The early life origin theory in the development of cardiovascular disease and type 2 diabetes.

    PubMed

    Lindblom, Runa; Ververis, Katherine; Tortorella, Stephanie M; Karagiannis, Tom C

    2015-04-01

    Life expectancy has been examined from a variety of perspectives in recent history. Epidemiology is one perspective which examines causes of morbidity and mortality at the population level. Over the past few 100 years there have been dramatic shifts in the major causes of death and expected life length. This change has suffered from inconsistency across time and space with vast inequalities observed between population groups. In current focus is the challenge of rising non-communicable diseases (NCD), such as cardiovascular disease and type 2 diabetes mellitus. In the search to discover methods to combat the rising incidence of these diseases, a number of new theories on the development of morbidity have arisen. A pertinent example is the hypothesis published by David Barker in 1995 which postulates the prenatal and early developmental origin of adult onset disease, and highlights the importance of the maternal environment. This theory has been subject to criticism however it has gradually gained acceptance. In addition, the relatively new field of epigenetics is contributing evidence in support of the theory. This review aims to explore the implication and limitations of the developmental origin hypothesis, via an historical perspective, in order to enhance understanding of the increasing incidence of NCDs, and facilitate an improvement in planning public health policy.

  6. A study of ion emissions in MAVEN/IUVS data

    NASA Astrophysics Data System (ADS)

    Connour, Kyle; Schneider, Nicholas M.; Deighan, Justin; Jain, Sonal Kumar; Stevens, Michael H.; Evans, Scott; Stewart, Ian; Crismani, Matteo; Stiepen, Arnaud; Chaffin, Michael S.; McClintock, William; Holsclaw, Gregory; Lefevre, Franck; Lo, Daniel; Clarke, John T.; Mayyasi, Majd A.; Montmessin, Franck; Jakosky, Bruce

    2016-10-01

    The Imaging Ultraviolet Spectrograph (IUVS) instrument on the Mars Atmosphere and Volatile EvolutionN (MAVEN) mission is designed to measure radiances of several of the most abundant species present in Mars' atmosphere. Many spectral features are associated with ions; one of the most prominent spectral features in the mid-ultraviolet region is the CO2+ Ultraviolet Doublet (UVD) at 289 nm. However this emission, and many others, results from several radiative processes, some of which originate from the ionization process and is therefore not diagnostic of the ion densities. Several other emissions are diagnostic of ion densities, especially at high altitudes, and therefore lend themselves to density retrievals based on inclusion of all radiative processes. The most promising of these is the Fox-Duffendack-Barker (FDB) (3,0) band at 314 nm, near the long-wavelength limit of the IUVS instrument. We report on a new process for performing density retrievals of CO2+ with particular attention to the credibility of high-altitude signal in the FDB bands as well as the associated uncertainties. We also investigate the feasibility of C+ and other ion density retrievals.

  7. Quasiclassical trajectory study of collisional energy transfer in toluene systems. II. Helium bath gas: Energy and temperature dependences, and angular momentum transfer

    NASA Astrophysics Data System (ADS)

    Lim, Kieran F.

    1994-11-01

    The collisional deactivation of highly vibrationally excited toluene-d0 and toluene-d8 by helium bath gas has been investigated using quasiclassical trajectory simulations. Collisional energy transfer was found to increase with initial toluene internal energy, in agreement with the experiments of Toselli and Barker [J. Chem. Phys. 97, 1809 (1992), and references therein]. The temperature dependence of <ΔE2>1/2 is predicted to be T(0.44±0.10), in agreement with the experiments of Heymann, Hippler, and Troe [J. Chem. Phys. 80, 1853 (1984)]. Toluene is found to have no net angular-momentum (rotational-energy) transfer to helium bath gas, although <ΔJ2>1/2 has a temperature dependence of T(0.31±0.07). Re-evaluation of earlier calculations [``Paper I:'' Lim, J. Chem. Phys. 100, 7385 (1994)] found that rotational energy transfer could be induced by increasing the mass of the collider, or by increasing the strength of the intermolecular interaction: in these cases, angular-momentum transfer depended on the initial excitation energy. In all cases, the final rotational distributions remained Boltzmann.

  8. Paternal HLA-C and Maternal Killer-Cell Immunoglobulin-Like Receptor Genotypes in the Development of Autism

    PubMed Central

    Gamliel, Moriya; Anderson, Karen L.; Ebstein, Richard P.; Yirmiya, Nurit; Mankuta, David

    2016-01-01

    Killer-cell immunoglobulin-like receptors (KIRs) are a family of cell surface proteins found on natural killer cells, which are components of the innate immune system. KIRs recognize MHC class I proteins, mainly HLA-C and are further divided into two groups: short-tailed 2/3DS activating receptors and long-tailed 2/3DL inhibitory receptors. Based on the Barker Hypothesis, the origins of illness can be traced back to embryonic development in the uterus, and since KIR:HLA interaction figures prominently in the maternal–fetal interface, we investigated whether specific KIR:HLA combinations may be found in autism spectrum disorders (ASD) children compared with their healthy parents. This study enrolled 49 ASD children from different Israeli families, and their healthy parents. Among the parents, a higher frequency of HLA-C2 allotypes was found in the fathers, while its corresponding ligand 2DS1 was found in higher percentage in the maternal group. However, such skewing in KIR:HLA frequencies did not appear in the ASD children. Additionally, analysis of “overall activation” indicated higher activation in maternal than in paternal cohorts. PMID:27517034

  9. A list of the 70 species of Australian ticks; diagnostic guides to and species accounts of Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus australis (Australian cattle tick); and consideration of the place of Australia in the evolution of ticks with comments on four controversial ideas.

    PubMed

    Barker, Stephen C; Walker, Alan R; Campelo, Dayana

    2014-10-15

    Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites).

  10. Third-order thermodynamic perturbation theory for effective potentials that model complex fluids

    NASA Astrophysics Data System (ADS)

    Zhou, Shiqi; Solana, J. R.

    2008-08-01

    We have performed Monte Carlo simulations to obtain the thermodynamic properties of fluids with two kinds of hard-core plus attractive-tail or oscillatory potentials. One of them is the square-well potential with small well width. The other is a model potential with oscillatory and decaying tail. Both model potentials are suitable for modeling the effective potential arising in complex fluids and fluid mixtures with extremely-large-size asymmetry, as is the case of the solvent-induced depletion interactions in colloidal dispersions. For the former potential, the compressibility factor, the excess energy, the constant-volume excess heat capacity, and the chemical potential have been obtained. For the second model potential only the first two of these quantities have been obtained. The simulations cover the whole density range for the fluid phase and several temperatures. These simulation data have been used to test the performance of a third-order thermodynamic perturbation theory (TPT) recently developed by one of us [S. Zhou, Phys. Rev. E 74, 031119 (2006)] as compared with the well-known second-order TPT based on the macroscopic compressibility approximation due to Barker and Henderson. It is found that the first of these theories provides much better accuracy than the second one for all thermodynamic properties analyzed for the two effective potential models.

  11. [Global trends in food consumption and nutrition].

    PubMed

    Holmboe-Ottesen, G

    2000-01-10

    Obesity and lifestyle diseases increase all over the world, especially in developing countries. One reason is the change in diet. This nutrition transition is characterised by improvement in dietary variation, but also by increase in the content of fat and sugar. The transition seems to start at a lower level of income, compared to what occurred in the Western countries after the Second World War. The reason is that many foods are relatively cheaper, especially fat and sugar. The world market is presently flooded with cheap vegetable fat. Urbanisation leads to over-consumption by increasing market access to fatty and sugary foods, including fast foods. Globalization increases the consumption of sweet soda pops, biscuits and snacks produced by multinational companies. Western supermarkets and fast food franchises also promote these dietary changes (McDonaldization). It has been proposed that the population in developing countries is more vulnerable towards these dietary changes in regard to obesity and chronic diseases, due to undernutrition in early life (the Barker hypothesis). We may therefore expect an unprecedented increase in the prevalence of chronic diseases, especially diabetes type 2 in the developing countries. One may question if this increase will be a transient phenomenon, or if we can expect the same pattern as we have seen in the West, namely that the poor become the fat-test segment of the population, with the highest prevalence of chronic diseases.

  12. Molecular equilibria and condensation sequences in carbon rich gases

    NASA Technical Reports Server (NTRS)

    Sharp, C. M.; Wasserburg, G. J.

    1993-01-01

    Chemical equilibria in stellar atmospheres have been investigated by many authors. Lattimer, Schramm, and Grossman presented calculations in both O rich and C rich environments and predicted possible presolar condensates. A recent paper by Cherchneff and Barker considered a C rich composition with PAH's included in the calculations. However, the condensation sequences of C bearing species have not been investigated in detail. In a carbon rich gas surrounding an AGB star, it is often assumed that graphite (or diamond) condenses out before TiC and SiC. However, Lattimer et al. found some conditions under which TiC condenses before graphite. We have performed molecular equilibrium calculations to establish the stability fields of C(s), TiC(s), and SiC(s) and other high temperature phases under conditions of different pressures and C/O. The preserved presolar interstellar dust grains so far discovered in meteorites are graphite, diamond, SiC, TiC, and possibly Al2O3.

  13. Behavior Analysis and Ecological Psychology: Past, Present, and Future. A Review of Harry Heft's Ecological Psychology in Context

    PubMed Central

    Morris, Edward K

    2009-01-01

    Relations between behavior analysis and ecological psychology have been strained for years, notwithstanding the occasional comment on their affinities. Harry Heft's (2001) Ecological Psychology in Context provides an occasion for reviewing anew those relations and affinities. It describes the genesis of ecological psychology in James's radical empiricism; addresses Holt's neorealism and Gestalt psychology; and synthesizes Gibson's ecological psychology and Barker's ecobehavioral science as a means for understanding everyday human behavior. Although behavior analysis is excluded from this account, Heft's book warrants a review nonetheless: It describes ecological psychology in ways that are congruent and complementary with behavior analysis (e.g., nonmediational theorizing; the provinces of natural history and natural science). After introducing modern ecological psychology, I comment on (a) Heft's admirable, albeit selective, historiography; (b) his ecological psychology—past and present—as it relates to Skinner's science and system (e.g., affordances, molar behavior); (c) his misunderstandings of Skinner's behaviorism (e.g., reductionistic, mechanistic, molecular); and (d) the theoretical status of Heft's cognitive terms and talk (i.e., in ontology, epistemology, syntax). I conclude by considering the alliance and integration of ecological psychology and behavior analysis, and their implications for unifying and transforming psychology as a life science, albeit more for the future than at present. PMID:20354604

  14. Theoretical and numerical investigations of inverse patchy colloids in the fluid phase

    SciTech Connect

    Kalyuzhnyi, Yurij V.; Bianchi, Emanuela Ferrari, Silvano; Kahl, Gerhard

    2015-03-21

    We investigate the structural and thermodynamic properties of a new class of patchy colloids, referred to as inverse patchy colloids (IPCs) in their fluid phase via both theoretical methods and simulations. IPCs are nano- or micro- meter sized particles with differently charged surface regions. We extend conventional integral equation schemes to this particular class of systems: our approach is based on the so-called multi-density Ornstein-Zernike equation, supplemented with the associative Percus-Yevick approximation (APY). To validate the accuracy of our framework, we compare the obtained results with data extracted from NpT and NVT Monte Carlo simulations. In addition, other theoretical approaches are used to calculate the properties of the system: the reference hypernetted-chain (RHNC) method and the Barker-Henderson thermodynamic perturbation theory. Both APY and RHNC frameworks provide accurate predictions for the pair distribution functions: APY results are in slightly better agreement with MC data, in particular at lower temperatures where the RHNC solution does not converge.

  15. Influence of Past Changes in Atmospheric CO2 on Boron/Calcium of Planktic Fossil Foraminifera

    NASA Astrophysics Data System (ADS)

    Domeyko, R. A.; Allen, K. A.; deMenocal, P. B.

    2014-12-01

    Culture experiments have revealed that B/Ca of shells grown by the foraminiferal species Globigerinoides ruber increase with increasing seawater pH. Specifically, B/Ca responds to changes in the relative abundance of pH-sensitive dissolved carbon and boron species (Allen et al. 2011, 2012). Here, we present a high-resolution study on fossilized G. ruber from two sites in North Atlantic subtropical gyres (VM25-21 and ODP 1055B) through 20 ka BP to evaluate how B/Ca responds to past changes in atmospheric CO2. Forams were picked and crushed gently, then cleaned and dissolved using a variation of the Boyle and Keigwin (1985) and Barker et al. (2003) cleaning protocols prior to analysis. ODP 1055B (from Carolina Slope, West Atlantic) produced a high-resolution record with lower B/Ca values during the glacial period followed by a rapid shift to higher B/Ca values in the early deglaciation, with values remaining high through the Holocene. These results were not predicted by culture calibrations, but they are consistent with B/Ca records from the Caribbean (ODP 999, Foster et al. 2008), suggesting this pattern is characteristic of surface waters in the greater North Atlantic region.

  16. Rural Alaska Coal Bed Methane: Application of New Technologies to Explore and Produce Energy

    SciTech Connect

    David O. Ogbe; Shirish L. Patil; Doug Reynolds

    2005-06-30

    The Petroleum Development Laboratory, University of Alaska Fairbanks prepared this report. The US Department of Energy NETL sponsored this project through the Arctic Energy Technology Development Laboratory (AETDL) of the University of Alaska Fairbanks. The financial support of the AETDL is gratefully acknowledged. We also acknowledge the co-operation from the other investigators, including James G. Clough of the State of Alaska Department of Natural Resources, Division of Geological and Geophysical Surveys; Art Clark, Charles Barker and Ed Weeks of the USGS; Beth Mclean and Robert Fisk of the Bureau of Land Management. James Ferguson and David Ogbe carried out the pre-drilling economic analysis, and Doug Reynolds conducted post drilling economic analysis. We also acknowledge the support received from Eric Opstad of Elko International, LLC; Anchorage, Alaska who provided a comprehensive AFE (Authorization for Expenditure) for pilot well drilling and completion at Fort Yukon. This report was prepared by David Ogbe, Shirish Patil, Doug Reynolds, and Santanu Khataniar of the University of Alaska Fairbanks, and James Clough of the Alaska Division of Geological and Geophysical Survey. The following research assistants, Kanhaiyalal Patel, Amy Rodman, and Michael Olaniran worked on this project.

  17. Solid{endash}fluid phase equilibrium for single component and binary Lennard-Jones systems: A cell theory approach

    SciTech Connect

    Cottin, X.; Monson, P.A.

    1996-12-01

    We consider the application of the cell theory to single component and binary Lennard-Jones solids. We calculate solid phase properties and solid{endash}fluid equilibrium using the cell theory for the solid phase and an equation of state for the fluid phase. In the single component case the thermodynamic properties as well as the solid{endash}fluid phase diagram predicted by the theory are in quite good agreement with Monte Carlo simulation results. The introduction of correlations between the motions of nearest neighbor particles into the cell theory in a fashion suggested by Barker significantly improves the agreement. For binary Lennard-Jones 12-6 mixtures the predictions of the theory are compared with experimental data for mixtures forming substitutionally disordered solid solutions involving argon, krypton and methane. The theory correctly predicts the form of the phase diagram but the quantitative predictions are quite sensitive to the choice of potential parameters. The shape of the phase diagram is similar to that for a hard sphere mixture with the same diameter ratio. {copyright} {ital 1996 American Institute of Physics.}

  18. Stability of Viscous St. Venant Roll Waves: From Onset to Infinite Froude Number Limit

    NASA Astrophysics Data System (ADS)

    Barker, Blake; Johnson, Mathew A.; Noble, Pascal; Rodrigues, L. Miguel; Zumbrun, Kevin

    2016-09-01

    We study the spectral stability of roll wave solutions of the viscous St. Venant equations modeling inclined shallow water flow, both at onset in the small Froude number or "weakly unstable" limit F→ 2^+ and for general values of the Froude number F, including the limit F→ + ∞. In the former, F→ 2^+ , limit, the shallow water equations are formally approximated by a Korteweg-de Vries/Kuramoto-Sivashinsky (KdV-KS) equation that is a singular perturbation of the standard Korteweg-de Vries (KdV) equation modeling horizontal shallow water flow. Our main analytical result is to rigorously validate this formal limit, showing that stability as F→ 2^+ is equivalent to stability of the corresponding KdV-KS waves in the KdV limit. Together with recent results obtained for KdV-KS by Johnson-Noble-Rodrigues-Zumbrun and Barker, this gives not only the first rigorous verification of stability for any single viscous St. Venant roll wave, but a complete classification of stability in the weakly unstable limit. In the remainder of the paper, we investigate numerically and analytically the evolution of the stability diagram as Froude number increases to infinity. Notably, we find transition at around F=2.3 from weakly unstable to different, large-F behavior, with stability determined by simple power-law relations. The latter stability criteria are potentially useful in hydraulic engineering applications, for which typically 2.5≤ F≤ 6.0.

  19. Twentieth workshop on geothermal reservoir engineering: Proceedings

    SciTech Connect

    1995-01-26

    PREFACE The Twentieth Workshop on Geothermal Reservoir Engineering, dedicated to the memory of Professor Hank Ramey, was held at Stanford University on January 24-26, 1995. There were ninety-five registered participants. Participants came from six foreign countries: Japan, Mexico, England, Italy, New Zealand and Iceland. The performance of many geothermal reservoirs outside the United States was described in several of the papers. Professor Roland N. Horne opened the meeting and welcomed visitors to the campus. The key note speaker was Marshall Reed, who gave a brief overview of the Department of Energy's current plan. Thirty-two papers were presented in the technical sessions of the workshop. Technical papers were organized into eleven sessions concerning: field development, modeling, well tesubore, injection, geoscience, geochemistry and field operations. Session chairmen were major contributors to the workshop, and we thank: Ben Barker, Bob Fournier, Mark Walters, John Counsil, Marcelo Lippmann, Keshav Goyal, Joel Renner and Mike Shook. In addition to the technical sessions, a panel discussion was held on ''What have we learned in 20 years?'' Panel speakers included Patrick Muffler, George Frye, Alfred Truesdell and John Pritchett. The subject was further discussed by Subir Sanyal, who gave the post-dinner speech at the banquet. The Workshop was organized by the Stanford Geothermal Program faculty, staff, and graduate students. We wish to thank our students who operated the audiovisual equipment. Shaun D. Fitzgerald Program Manager

  20. Enacting a social ecology: radically embodied intersubjectivity

    PubMed Central

    McGann, Marek

    2014-01-01

    Embodied approaches to cognitive science frequently describe the mind as “world-involving,” indicating complementary and interdependent relationships between an agent and its environment. The precise nature of the environment is frequently left ill-described, however, and provides a challenge for such approaches, particularly, it is noted here, for the enactive approach which emphasizes this complementarity in quite radical terms. This paper argues that enactivists should work to find common cause with a dynamic form of ecological psychology, a theoretical perspective that provides the most explicit theory of the psychological environment currently extant. In doing so, the intersubjective, cultural nature of the ecology of human psychology is explored, with the challenges this poses for both enactivist and ecological approaches outlined. The theory of behavior settings (Barker, 1968; Schoggen, 1989) is used to present a framework for resolving some of these challenges. Drawing these various strands together an outline of a radical embodied account of intersubjectivity and social activity is presented. PMID:25477844

  1. Molecular cloning and primary structure of the Escherichia coli methionyl-tRNA synthetase gene.

    PubMed Central

    Dardel, F; Fayat, G; Blanquet, S

    1984-01-01

    The intact metG gene was cloned in plasmid pBR322 from an F32 episomal gene library by complementation of a structural mutant, metG83. The Escherichia coli strain transformed with this plasmid (pX1) overproduced methionyl-tRNA synthetase 40-fold. Maxicell analysis showed that three major polypeptides with MrS of 76,000, 37,000, and 29,000 were expressed from pX1. The polypeptide with an Mr of 76,000 was identified as the product of metG on the basis of immunological studies and was indistinguishable from purified methionyl-tRNA synthetase. In addition, DNA-DNA hybridization studies demonstrated that the metG regions were homologous on the E. coli chromosome and on the F32 episome. DNA sequencing of 642 nucleotides was performed. It completes the partial metG sequence already published (D. G. Barker, J. P. Ebel, R. Jakes, and C. J. Bruton, Eur. J. Biochem. 127:449-451, 1982). Examination of the deduced primary structure of methionyl-tRNA synthetase excludes the occurrence of any significant repeated sequences. Finally, mapping of mutation metG83 by complementation experiments strongly suggests that the central part of methionyl-tRNA synthetase is involved in methionine recognition. This observation is discussed in the light of the known three-dimensional crystallographic structure. Images PMID:6094501

  2. The identification and characteristics of Echinoparyphium rubrum (Cort. 1914) new comb. (Trematoda, Echinostomatidae) based on experimental evidence of the life cycle

    USGS Publications Warehouse

    Kanev, I.; Sorensen, R.; Sterner, M.; Cole, R.; Fried, B.

    1998-01-01

    The life cycle of Echinoparyphium rubrum (Cort, 1914) comb. n. has been completed experimentally. All of the developmental stages egg, miracidium, sporocyst, mother and daughter rediae, cercaria, metacercaria, and adult were examined and described. The miracidia infected freshwater snails of the genus Physa , P. gyrina and P. occidentalis. Attempts to infect snails of the genera Lymnaea, L. auricularis, L. peregra, L. truncatula and Bulinus, B. truncatus failed. Cercariae infected various pulmonate and prosobranch freshwater snails, mussels, frogs, water turtles and planarians. The adults developed in the small intestine of birds and mammals. The identity and major characteristics of Echinoparyphium rubrum are discussed. Synonyms of E. rubrum are Cercaria rubra Cort, 1914; Cercaria biflexa Faust, 1917; Cercaria chisolenata Faust, 1918; Echinostoma callawayensis Barker et Noll, 1915; Echinostoma revolutum of Johnson (1920); Echinoparyphium elegans of Cannon (1938), of Bain and Trelfall (1977), of Mahoney and Trelfall (1977); and Echinoparyphium recurvatum of Jilek (1977), Harley (1972), Sankurathri and Holmes (1976). Comparisons are made between E. rubrum and its 43-collar-spined allies: E. flexum from North America, E. cinctum from Europe, E. dunni from Asia and E. elegans from Africa.

  3. Mate loss affects survival but not breeding in black brant geese

    USGS Publications Warehouse

    Nicolai, Christopher A.; Sedinger, James S.; Ward, David H.; Boyd, W. Sean

    2012-01-01

    For birds maintaining long-term monogamous relationships, mate loss might be expected to reduce fitness, either through reduced survival or reduced future reproductive investment. We used harvest of male brant during regular sport hunting seasons as an experimental removal to examine effects of mate loss on fitness of female black brant (Branta bernicla nigricans; hereafter brant). We used the Barker model in program MARK to examine effects of mate loss on annual survival, reporting rate, and permanent emigration. Survival rates decreased from 0.847 ± 0.004 for females who did not lose their mates to 0.690 ± 0.072 for birds who lost mates. Seber ring reporting rate for females that lost their mates were 2 times higher than those that did not lose mates, 0.12 ± 0.086 and 0.06 ± 0.006, respectively, indicating that mate loss increased vulnerability to harvest and possibly other forms of predation. We found little support for effects of mate loss on fidelity to breeding site and consequently on breeding. Our results indicate substantial fitness costs to females associated with mate loss, but that females who survived and were able to form new pair bonds may have been higher quality than the average female in the population.

  4. What Does It Mean to be Central? A Botanical Geography of Paris 1830-1848.

    PubMed

    Hoquet, Thierry

    2016-02-01

    This paper focuses on the geography of the botanical community in Paris, under the July Monarchy (1830-1848). At that time, the Muséum d'Histoire naturelle (MHN) was at its institutional acme and, under the impulse of François Guizot, its budget was increasing dramatically. However, closer attention to manuscript sources (correspondence, travel diaries) reveals that the botanists of the time favoured other private institutions, located both on the Right and Left Banks of the Seine. The MHN was prestigious for its collections and professors but it was relatively remote from the centre of Paris, and its plant samples were sometimes difficult to access. Several other first-class private herbaria granted liberal access to botanists: those of Jacques Gay, Phillip Barker Webb, and Benjamin Delessert. Thanks to their wealth, these plant amateurs had ownership of historical herbaria consisting of species types alongside rich botanical libraries. Botanists visiting Paris from foreign countries or other provinces of France also spent some time studying less general plant collections, like those of Count Jaubert, or specialized collections, like Montagne's or Léveillé's on cryptogams. Other botanists also enjoyed renown at the time, although they published little, if anything (like Maire). Living in crammed apartments, literally in the middle of their plant samples, these botanists were key nodes in botanical networks, although they had no relation with the prestigious MHN.

  5. Industrially induced changes in Earth structure at the geysers geothermal area, California

    USGS Publications Warehouse

    Foulger, G.R.; Grant, C.C.; Ross, A.; Julian, B.R.

    1997-01-01

    Industrial exploitation is causing clearly-measurable changes in Earth structure at The Geysers geothermal area, California. Production at The Geysers peaked in the late 1980s at ???3.5 ?? 103 kg s-1 of steam and 1800 MW of electricity. It subsequently decreased by about 10% per year [Barker et al., 1992] because of declining reservoir pressure. The steam reservoir coincides with a strong negative anomaly (???0.16, ???9%) in the compressional-to-shear seismic wave speed ratio vP/vS, consistent with the expected effects of low-pressure vapor-phase pore fluid [Julian et al., 1996]. Between 1991 and 1994 this anomaly increased in amplitude by up to about 0.07 (???4%). This is consistent with the expected effects of continued pressure reduction and conversion of pore water to steam as a result of exploitation. These unique results show that vP/vS tomography can easily detect saturation changes caused by exploitation of reservoirs, and is a potentially valuable technique for monitoring environmental change. They also provide geophysical observational evidence that geothermal energy is not a renewable energy source.

  6. An efficient method for unfolding kinetic pressure driven VISAR data

    DOE PAGES

    Mark Harry Hess; Peterson, Kyle; Harvey-Thompson, Adam James

    2015-08-18

    Velocity Interferometer System for Any Reflector (VISAR) [Barker and Hollenbach, J. Appl. Phys. 43, 4669 (1972)] is a well-known diagnostic that is employed on many shock physics and pulsed-power experiments. With the VISAR diagnostic, the velocity on the surface of any metal flyer can be found. For most experiments employing VISAR, either a kinetic pressure [Grady, Mech. Mater. 29, 181 (1998)] or a magnetic pressure [Lemke et al., Intl J. Impact Eng. 38, 480 (2011)] drives the motion of the flyer. Moreover, reliable prediction of the time-dependent pressure is often a critical component to understanding the physics of these experiments.more » Although VISAR can provide a precise measurement of a flyer’s surface velocity, the real challenge of this diagnostic implementation is using this velocity to unfold the time-dependent pressure. The purpose of this study is to elucidate a new method for quickly and reliably unfolding VISAR data.« less

  7. The origins of health and disease: the influence of maternal diseases and lifestyle during gestation

    PubMed Central

    2013-01-01

    According to the Barker hypothesis, the period of pregnancy and the intrauterine environment are crucial to the tendency to develop diseases like hypertension, diabetes, coronary heart disease, metabolic disorders, pulmonary, renal and mental illnesses. The external environment affects the development of a particular phenotype suitable for an environment with characteristics that closely resemble intrauterine conditions. If the extra-uterine environment differs greatly from the intra-uterine one, the fetus is more prone to develop disease. Subsequent studies have shown that maternal diseases like depression and anxiety, epilepsy, asthma, anemia and metabolic disorders, like diabetes, are able to determine alterations in growth and fetal development. Similarly, the maternal lifestyle, particularly diet, exercise and smoking during pregnancy, have an important role in determining the risk to develop diseases that manifest themselves both during childhood and particularly in adulthood. Finally, there are abundant potential sources of pollutants, both indoor and outdoor, in the environment in which the child lives, which can contribute to an increased probability to the development of several diseases and that in some cases could be easily avoided. PMID:23343462

  8. ALTAIR observations of post-sunset E region irregularities during Equis 2 Campaign

    NASA Astrophysics Data System (ADS)

    Kudeki, E.; Wallace, A.

    2006-05-01

    In August/September 2004 the ALTAIR VHF/UHF radar located on Roi-Namur island of the Kwajalein Atoll radar was used to monitor the E- and F-region ionosphere in support of the NASA Equis 2 rocket campaign. The ALTAIR radar operates in two frequency bands centered about 158 MHz and 422 MHz respectively and has a horizon to horizon scanning capability based on mechanical steering of its parabolic reflector. The facility supported the NASA Equis 2 Campaign with a limited number of pulse waveform modes and range resolutions as fine as 150 m. During the September 1-17 window 13 sessions of post-sunset sporadic-E backscatter experiments were conducted. The VHF experiment used 13-baud Barker coded pulses of 1 microsecond baud length while the UHF employed an 88 baud code with the same baud length. The measurements were conducted with an IPP of 10 ms and 2500 range gates were sampled at 60 m intervals beginning at a range of 80 km. The radar beam was typically scanned in the zonal plane from west to east while maintaining a perpendicular orientation to the geomagnetic field in E-region heights. Coherent backscatter response observed at both frequencies (VHF and UHF) was most intense in the period immediately after sunset, although sporadic episodes of unstable layers were observed occasionally as late as local midnight. Absolute cross sections of UHF and VHF echoes from post-sunset E-region irregularities will be presented.

  9. New techniques for auroral irregularity studies with COSCAT

    NASA Astrophysics Data System (ADS)

    Eglitis, P.; McCrea, I. W.; Robinson, T. R.; Nygrén, T.; Schlegel, K.; Turunen, T.; Jones, T. B.

    1998-10-01

    The COSCAT system enables the detection of E-region auroral backscatter with the EISCAT remote receivers at magnetic aspect angles close to 90 °. This is achieved by utilising a low-power transmitter stationed in Oulu, Finland. Many important observations of E-region irregularities have been achieved with this simple experiment. Recent studies have attempted to push the COSCAT system to its experimental limits. Firstly, the CW signal has been phase-modulated with 13-bit Barker codes with baud lengths of 40, 70 and 100 µs. Interpretation of the received power allows the spatial distribution of the auroral scatterers to be determined. The second advance is in the use of a sophisticated correlator program which allows data to be buffered within the correlator at very high time resolution. This enables the coherent backscatter power to be sampled every 12.5 ms and the full auto-correlation function to be measured every 100 ms. These measurements allow the COSCAT system to be employed for the first time in an investigation of the growth and decay of the auroral irregularities.

  10. D-Region studies with PFISR

    NASA Astrophysics Data System (ADS)

    Janches, D.; Nicolls, M. J.; Fritts, D. C.; Heinselman, C.

    2007-12-01

    We present observations of the polar D-region performed with the new Poker Flat Incoherent Scatter Radar (PFISR). The observations were performed during a 24-hr period near summer solstice covering the 40 to 140 km altitude range and were designed to measure the radar return from 4 pointing directions, ~10 degrees east, south, north and west from zenith. We utilized a 13-baud, 130 us Barker code (1.5 km resolution) and a 2 ms IPP in order to obtain precise spectral information from this region of the ionosphere. The results indicate that PFISR will be a powerful tool to study the high latitude D region. We will show and discuss results that include meridional and zonal wind profiles extending from 65 to 95 km as well as estimates of the vertical flux of both the zonal and meridional momentum, measurements that are facilitated by PFISR's ability to steer on a pulse-to- pulse basis. We will also show characteristics of the spectra before, during and after the occurrence of polar mesospheric summer echoes (PMSE). In particular, we find that clear and narrow D-region spectra seem to be measured only around the times when PMSE are present. We investigate and discuss possible reasons for this correlation.

  11. Volumetric imaging of the auroral ionosphere: Initial results from PFISR

    NASA Astrophysics Data System (ADS)

    Semeter, Joshua; Butler, Thomas; Heinselman, Craig; Nicolls, Michael; Kelly, John; Hampton, Donald

    2009-05-01

    The Poker Flat Incoherent Scatter Radar (PFISR) is the first dedicated ISR built with an electronically steerable array. This paper demonstrates the capabilities of PFISR for producing three-dimensional volumetric images of E-region ionization patterns produced by the aurora. The phase table was configured to cycle through 121 beam positions arranged in an 11×11 grid. A 13-baud Barker coded pulse was used, which provided ~1.5-km range resolution out to a maximum range of 250 km. Backscattered power was converted to electron density by correcting for path loss and applying the Buneman approximation assuming equal electron and ion temperatures. The results were then interpolated onto a three-dimensional cartesian grid. Volumetric images are presented at 5-min, 1-min, and 14.6-s integration times (corresponding to 960, 192, and 48 pulses-per-position, respectively) to illustrate the tradeoff between spatio-temporal resolution and data quality. At 14.6 s cadence, variability in plasma density within the volume appears to be fully resolved in space and time, a result that is supported by both observational evidence and theoretical predictions of ionospheric response times. Some potential applications of this mode for studying magnetosphere-ionosphere interactions in the auroral zone are discussed.

  12. Adaptive wavelet detection of transients using the bootstrap

    NASA Astrophysics Data System (ADS)

    Hewer, Gary A.; Kuo, Wei; Peterson, Lawrence A.

    1996-03-01

    A Daubechies wavelet-based bootstrap detection strategy based on the research of Carmona was applied to a set of test signals. The detector was a function of the d-scales. The adaptive detection statistics were derived using Efron's bootstrap methodology, which relieved us from having to make parametric assumptions about the underlying noise and offered a method of overcoming the constraints of modeling the detector statistics. The test set of signals used to evaluate the Daubechies/bootstrap pulse detector were generated with a Hewlett-Packard Fast Agile Signal Simulator (FASS). These video pulses, with varying signal-to-noise ratios (SNRs), included unmodulated, linear chirp, and Barker phase-code modulations baseband (IF) video pulses mixed with additive white Gaussian noise. Simulated examples illustrating the bootstrap methodology are presented, along with a complete set of constant false alarm rate (CFAR) detection statistics for the test signals. The CFAR curves clearly show that the wavelet bootstrap can adaptively detect transient pulses at low SNRs.

  13. The programming of cardiovascular disease.

    PubMed

    Thornburg, K L

    2015-10-01

    In spite of improving life expectancy over the course of the previous century, the health of the U.S. population is now worsening. Recent increasing rates of type 2 diabetes, obesity and uncontrolled high blood pressure predict a growing incidence of cardiovascular disease and shortened average lifespan. The daily >$1billion current price tag for cardiovascular disease in the United States is expected to double within the next decade or two. Other countries are seeing similar trends. Current popular explanations for these trends are inadequate. Rather, increasingly poor diets in young people and in women during pregnancy are a likely cause of declining health in the U.S. population through a process known as programming. The fetal cardiovascular system is sensitive to poor maternal nutritional conditions during the periconceptional period, in the womb and in early postnatal life. Developmental plasticity accommodates changes in organ systems that lead to endothelial dysfunction, small coronary arteries, stiffer vascular tree, fewer nephrons, fewer cardiomyocytes, coagulopathies and atherogenic blood lipid profiles in fetuses born at the extremes of birthweight. Of equal importance are epigenetic modifications to genes driving important growth regulatory processes. Changes in microRNA, DNA methylation patterns and histone structure have all been implicated in the cardiovascular disease vulnerabilities that cross-generations. Recent experiments offer hope that detrimental epigenetic changes can be prevented or reversed. The large number of studies that provide the foundational concepts for the developmental origins of disease can be traced to the brilliant discoveries of David J.P. Barker.

  14. Indo-Pacific bottlenose dolphin (Tursiops aduncus) habitat preference in a heterogeneous, urban, coastal environment

    PubMed Central

    2013-01-01

    Background Limited information is available regarding the habitat preference of the Indo-Pacific bottlenose dolphin (Tursiops aduncus) in South Australian estuarine environments. The need to overcome this paucity of information is crucial for management and conservation initiatives. This preliminary study investigates the space-time patterns of habitat preference by the Indo-Pacific bottlenose dolphin in the Port Adelaide River-Barker Inlet estuary, a South Australian, urbanised, coastal environment. More specifically, the study aim was to identify a potential preference between bare sand substrate and seagrass beds, the two habitat types present in this environment, through the resighting frequency of recognisable individual dolphins. Results Photo-identification surveys covering the 118 km2 sanctuary area were conducted over 2 survey periods May to August 2006 and from March 2009 to February 2010. Sighting frequency of recognisable individual Indo-Pacific bottlenose dolphins established a significant preference for the bare sand habitat. More specifically, 72 and 18% of the individuals sighted at least on two occasions were observed in the bare sand and seagrass habitats respectively. This trend was consistently observed at both seasonal and annual scales, suggesting a consistency in the distinct use of these two habitats. Conclusions It is anticipated that these results will benefit the further development of management and conservation strategies. PMID:23369354

  15. Feasibility of coded vibration in a vibro-ultrasound system for tissue elasticity measurement.

    PubMed

    Zhao, Jinxin; Wang, Yuanyuan; Yu, Jinhua; Li, Tianjie; Zheng, Yong-Ping

    2016-07-01

    The ability of various methods for elasticity measurement and imaging is hampered by the vibration amplitude on biological tissues. Based on the inference that coded excitation will improve the performance of the cross-correlation function of the tissue displacement waves, the idea of exerting encoded external vibration on tested samples for measuring its elasticity is proposed. It was implemented by integrating a programmable vibration generation function into a customized vibro-ultrasound system to generate Barker coded vibration for elasticity measurement. Experiments were conducted on silicone phantoms and porcine muscles. The results showed that coded excitation of the vibration enhanced the accuracy and robustness of the elasticity measurement especially in low signal-to-noise ratio scenarios. In the phantom study, the measured shear modulus values with coded vibration had an R(2 )= 0.993 linear correlation to that of referenced indentation, while for single-cycle pulse the R(2) decreased to 0.987. In porcine muscle study, the coded vibration also obtained a shear modulus value which is more accurate than the single-cycle pulse by 0.16 kPa and 0.33 kPa at two different depths. These results demonstrated the feasibility and potentiality of the coded vibration for enhancing the quality of elasticity measurement and imaging. PMID:27475130

  16. Gender differences in developmental programming of cardiovascular diseases

    PubMed Central

    Dasinger, John Henry; Alexander, Barbara T.

    2016-01-01

    Hypertension is a risk factor for cardiovascular disease, the leading cause of death worldwide. Although multiple factors contribute to the pathogenesis of hypertension, studies by Dr. David Barker reporting an inverse relationship between birth weight and blood pressure led to the hypothesis that slow growth during fetal life increases blood pressure and the risk for cardiovascular disease in later life. It is now recognized that growth during infancy and childhood in addition to exposure to adverse influences during fetal life contribute to the developmental programming of increased cardiovascular risk. Numerous epidemiological studies support the link between influences during early life with later cardiovascular health; experimental models provide proof of principle and indicate that numerous mechanisms contribute to the developmental origins of chronic disease. Sex impacts the severity of cardiovascular risk in experimental models of developmental insult. Yet, few studies examine the influence of sex on blood pressure and cardiovascular health in low birth weight men and women. Fewer still assess how aging impacts sex differences in programmed cardiovascular risk. Thus, the aim of this review is to highlight current data regarding sex differences in the developmental programming of blood pressure and cardiovascular disease. PMID:26814204

  17. Effects of Atmospheric Dust on Residual South Polar Cap Stability

    NASA Technical Reports Server (NTRS)

    Bonrv, B. P.; Bjorkman, J. E.; Hansen, G. B.; James, P. B.; Wolff, M. J.

    2005-01-01

    The Martian polar caps have been studied from the time of Herschel. Neither polar cap normally disappears in summer. The Residual North Polar Cap (portion that remains through summer) is composed of a mixture of water ice and dust, and its interannual stability is due to its low sublimation rate at the summer temperatures in the North Polar Region. The Residual South Polar Cap (RSPC) is more enigmatic, surviving the relatively hot perihelic summer season despite being composed of much more volatile CO2. It is able to do so because of its unusually high albedo, which is larger than that of other bright regions in the seasonal cap (e.g. Mountains of Mitchel). The proximity of the albedo of the RSPC to the critical albedo for stability raises the question of whether the RSPC exists in every Martian year. The ground based record is somewhat ambivalent. Douglass and Lowell reported that RSPC suddenly vanished at Ls=297deg in 1894 and did not reappear until Ls=0deg [1], and Kuiper reported that it disappeared in 1956 [2]; but both observations were questioned by contemporaries, who tended to attribute them to obscuring dust. Barker [3] reported a large amount of water vapor over the south polar cap in 1969 that could be attributed to exposure of near surface water ice during partial removal of the CO2 in the RSPC in 1969.

  18. Coded excitation plane wave imaging for shear wave motion detection.

    PubMed

    Song, Pengfei; Urban, Matthew W; Manduca, Armando; Greenleaf, James F; Chen, Shigao

    2015-07-01

    Plane wave imaging has greatly advanced the field of shear wave elastography thanks to its ultrafast imaging frame rate and the large field-of-view (FOV). However, plane wave imaging also has decreased penetration due to lack of transmit focusing, which makes it challenging to use plane waves for shear wave detection in deep tissues and in obese patients. This study investigated the feasibility of implementing coded excitation in plane wave imaging for shear wave detection, with the hypothesis that coded ultrasound signals can provide superior detection penetration and shear wave SNR compared with conventional ultrasound signals. Both phase encoding (Barker code) and frequency encoding (chirp code) methods were studied. A first phantom experiment showed an approximate penetration gain of 2 to 4 cm for the coded pulses. Two subsequent phantom studies showed that all coded pulses outperformed the conventional short imaging pulse by providing superior sensitivity to small motion and robustness to weak ultrasound signals. Finally, an in vivo liver case study on an obese subject (body mass index = 40) demonstrated the feasibility of using the proposed method for in vivo applications, and showed that all coded pulses could provide higher SNR shear wave signals than the conventional short pulse. These findings indicate that by using coded excitation shear wave detection, one can benefit from the ultrafast imaging frame rate and large FOV provided by plane wave imaging while preserving good penetration and shear wave signal quality, which is essential for obtaining robust shear elasticity measurements of tissue.

  19. The typical developmental trajectory of social and executive functions in late adolescence and early adulthood.

    PubMed

    Taylor, Sophie Jane; Barker, Lynne Ann; Heavey, Lisa; McHale, Sue

    2013-07-01

    Executive functions and social cognition develop through childhood into adolescence and early adulthood and are important for adaptive goal-oriented behavior (Apperly, Samson, & Humphreys, 2009; Blakemore & Choudhury, 2006). These functions are attributed to frontal networks known to undergo protracted maturation into early adulthood (Barker, Andrade, Morton, Romanowski, & Bowles, 2010; Lebel, Walker, Leemans, Phillips, & Beaulieu, 2008), although social cognition functions are also associated with widely distributed networks. Previously, nonlinear development has been reported around puberty on an emotion match-to-sample task (McGivern, Andersen, Byrd, Mutter, & Reilly, 2002) and for IQ in midadolescence (Ramsden et al., 2011). However, there are currently little data on the typical development of social and executive functions in late adolescence and early adulthood. In a cross-sectional design, 98 participants completed tests of social cognition and executive function, Wechsler Abbreviated Scale of Intelligence (Wechsler, 1999), Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988), Hospital Anxiety and Depression Scale (Zigmond & Snaith, 1983), and measures of pubertal development and demographics at ages 17, 18, and 19. Nonlinear age differences for letter fluency and concept formation executive functions were found, with a trough in functional ability in 18-year-olds compared with other groups. There were no age group differences on social cognition measures. Gender accounted for differences on 1 scale of concept formation, 1 dynamic social interaction scale, and 2 empathy scales. The clinical, developmental, and educational implications of these findings are discussed. PMID:22946438

  20. Narrating ageing: deconstructing negative conceptions of old age in four contemporary English novels.

    PubMed

    Oró-Piqueras, Maricel

    2013-01-01

    Characters in their late sixties, seventies and even eighties have become the main protagonists and narrators in contemporary fiction. Narratives of ageing not only allow the reader to go into deep confines of an ageing protagonist, they also offer a detailed account of how these protagonists as well as the society around them deal with an increasing reality within the Western world, namely, that a demographic change is taking place and, thus, social and individual conceptions related to old age and ageing need to be revised and redefined. Novels such as Pat Barker's The Century's Daughter, Margaret Forster's Diary of an Ordinary Woman, Doris Lessing's The Diaries of Jane Somers and Rose Tremain's The Cupboard invite the reader to explore the ageing process, both at an individual and social level, through the stories their main protagonists narrate to a member of a younger generation. As a human complex process within a broader demographic change, stories of ageing succeed in helping young and old protagonists (and ultimately the reader) to reflect on the ageing process from a multiplicity of perspectives. PMID:23273556

  1. Teacher management behaviors and pupil task involvement during small group laboratory activities

    NASA Astrophysics Data System (ADS)

    Beasley, Warren

    A major concern of many beginning and experienced teachers is that of classroom management and control. This article describes recent research into defining classroom management procedures that are used by high school science teachers and their relationship to pupil ontaskness. The classroom is conceptualized as a manipulable behavioral system. This construct arises directly from Barker's (1968) ecological psychology, the classroom and its occupants being conceptualized as a behavior setting. The behaviors of the teacher and the pupils are an integral part of the unit (behavior setting), which in turn coerces certain behaviors from its participants. Thus settings, and, in particular, subsettings, are seen as more important determiners of social behavior than the personality of individual teacher or pupil. The methodology employed in this research has involved the extensive use of video in naturalistic science classrooms. Tapes of both teacher and pupil behaviors were continuously and independently recorded. Intensive analysis using electronic recording instruments interfaced with the computer has allowed the collection and sophisticated analysis of the observational data. Data relating to teacher management behavior in small group settings have been analyzed and the relationships to pupil task involvement have been explored.

  2. Assessing the passerine "Tapestry": phylogenetic relationships of the Muscicapoidea inferred from nuclear DNA sequences.

    PubMed

    Cibois, Alice; Cracraft, Joel

    2004-07-01

    This study presents new comparative sequence data from the nuclear RAG-1 gene for an increased taxon sample in order to investigate phylogenetic relationships among a diverse songbird superfamily, the Muscicapoidea, which has variously included the waxwings, silky flycatchers, Palm Chat, dippers, starlings, mockingbirds, thrushes, chats, and Old World flycatchers. At the same time, our results provide a test of the often-cited relationships inferred from the phenetic studies of Sibley and Ahlquist [Phylogeny and Classification of Birds: A Study in Molecular Evolution. Yale University Press, New Haven, 1990] using DNA hybridization distances. Nuclear DNA sequences confirm the monophyly of the "core muscicapoid" group, as defined by Barker et al. [Proc. R. Soc. Lond. B 269 (2002) 295] and also support the sister-group relationship of the Sturnidae and Mimidae, on the one hand, and the large-bodied thrushes (Turdini)+the Old World flycatchers and robins, on the other. The results of the phylogenetic analysis allow preliminary inferences about muscicapoid biogeographic history.

  3. Detection optimization using linear systems analysis of a coded aperture laser sensor system

    SciTech Connect

    Gentry, S.M.

    1994-09-01

    Minimum detectable irradiance levels for a diffraction grating based laser sensor were calculated to be governed by clutter noise resulting from reflected earth albedo. Features on the earth surface caused pseudo-imaging effects on the sensor`s detector arras that resulted in the limiting noise in the detection domain. It was theorized that a custom aperture transmission function existed that would optimize the detection of laser sources against this clutter background. Amplitude and phase aperture functions were investigated. Compared to the diffraction grating technique, a classical Young`s double-slit aperture technique was investigated as a possible optimized solution but was not shown to produce a system that had better clutter-noise limited minimum detectable irradiance. Even though the double-slit concept was not found to have a detection advantage over the slit-grating concept, one interesting concept grew out of the double-slit design that deserved mention in this report, namely the Barker-coded double-slit. This diffractive aperture design possessed properties that significantly improved the wavelength accuracy of the double-slit design. While a concept was not found to beat the slit-grating concept, the methodology used for the analysis and optimization is an example of the application of optoelectronic system-level linear analysis. The techniques outlined here can be used as a template for analysis of a wide range of optoelectronic systems where the entire system, both optical and electronic, contribute to the detection of complex spatial and temporal signals.

  4. Demonstration of LED Retrofit Lamps at the Jordan Schnitzer Museum of Art

    SciTech Connect

    Miller, Naomi J.

    2011-09-01

    The Jordan Schnitzer Museum of Art in Eugene, Oregon, houses a remarkable permanent collection of Asian art and antiquities, modern art, and sculpture, and also hosts traveling exhibitions. In the winter and spring of 2011, a series of digital photographs by artist Chris Jordan, titled "Running the Numbers," was exhibited in the Coeta and Donald Barker Special Exhibitions Gallery. These works graphically illustrate waste (energy, money, health, consumer objects, etc.) in contemporary culture. The Bonneville Power Administration and the Eugene Water and Electricity Board provided a set of Cree 12W light-emitting diode (LED) PAR38 replacement lamps (Cree LRP38) for the museum to test for accent lighting in lieu of their standard Sylvania 90W PAR38 130V Narrow Flood lamps (which draw 78.9W at 120V). At the same time, the museum tested LED replacement lamps from three other manufacturers, and chose the Cree lamp as the most versatile and most appropriate color product for this exhibit. The lamps were installed for the opening of the show in January 2011. This report describes the process for the demonstration, the energy and economic results, and results of a survey of the museum staff and gallery visitors on four similar clusters of art lighted separately by four PAR38 lamps.

  5. Quantum vs Classical Mechanics for a 'Simple' Dissociation Reaction. Should They Give the Same Results?

    NASA Astrophysics Data System (ADS)

    Holloway, Stephen

    1997-03-01

    When performing molecular dynamical simulations on light systems at low energies, there is always the risk of producing data that bear no similarity to experiment. Indeed, John Barker himself was particularly anxious about treating Ar scattering from surfaces using classical mechanics where it had been shown experimentally in his own lab that diffraction occurs. In such cases, the correct procedure is probably to play the trump card "... well of course, quantum effects will modify this so that....." and retire gracefully. For our particular interests, the tables are turned in that we are interested in gas-surface dynamical studies for highly quantized systems, but would be interested to know when it is possible to use classical mechanics in order that a greater dimensionality might be treated. For molecular dissociation and scattering, it has been oft quoted that the greater the number of degrees of freedom, the more appropriate is classical mechanics, primarily because of the mass averaging over the quantized dimensions. Is this true? We have been investigating the dissociation of hydrogen molecules at surfaces and in this talk I will present quantum results for dissociation and scattering, along with a novel method for their interpretation based upon adiabatic potential energy surfaces. Comparison with classical calculations will be made and conclusions drawn. a novel method for their interpretation based upon adiabatic potential energy surfaces

  6. Ovarian LGR5 is critical for successful pregnancy

    PubMed Central

    Sun, Xiaofei; Terakawa, Jumpei; Clevers, Hans; Barker, Nick; Daikoku, Takiko; Dey, Sudhansu K.

    2014-01-01

    Leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) is expressed in many organs, including female reproductive organs, and is a stem cell marker in the stomach and intestinal epithelium, hair follicles, and ovarian surface epithelium. Despite ongoing studies, the definitive physiological functions of Lgr5 remain unclear. We utilized mice with conditional deletion of Lgr5 (Lgr5d/d) in the female reproductive organs by progesterone receptor-Cre (PgrCre) to determine Lgr5's functions during pregnancy. Only 30% of plugged Lgr5d/d females delivered live pups, and their litter sizes were lower. We found that pregnancy failure in Lgr5d/d females was due to insufficient ovarian progesterone (P4) secretion that compromised decidualization, terminating pregnancy. The drop in P4 levels was reflected in elevated levels of P4-metabolizing enzyme 20α-hydroxysteroid dehydrogenase in corpora lutea (CL) inactivated of Lgr5. Of interest, P4 supplementation rescued decidualization failure and supported pregnancy to full term in Lgr5d/d females. These results provide strong evidence that Lgr5 is critical to normal CL function, unveiling a new role of LGR5 in the ovary.—Sun, X., Terakawa, J., Clevers, H., Barker, N., Daikoku, T., Dey, S. K. Ovarian LGR5 is critical for successful pregnancy. PMID:24469993

  7. Clonal groups of Salmonella typhimurium in New York State.

    PubMed Central

    McDonough, P L; Timoney, J F; Jacobson, R H; Khakhria, R

    1989-01-01

    The epidemiology of 278 strains of Salmonella typhimurium isolated from 1973 to 1981 from animals in New York State was studied by using four "fingerprinting" techniques, bacteriophage type (B.R. Callow, J. Hyg. 57:346-359, 1959), biotype (J. P. Duguid, E. S. Anderson, G. A. Alfredsson, R. Barker, and D. C. Old, J. Med. Microbiol. 8:149-166, 1975), plasmid profile, and antibiogram. Phage type with biotype was the most useful marker for distinguishing clonal groups of S. typhimurium. Four clones of S. typhimurium predominated, i.e., phage type/biotypes U275/26, 49/26, 10/3, and 2/3. U275/26 and 49/26 were commonly found until 1976, but clones 10/3 and 2/3 were predominant after 1976. Comparison of results with data from Canada suggested a dissemination of strains of S. typhimurium between Canada and New York. Cattle were a common source of phage type 49, as has been observed in other countries. PMID:2656740

  8. In utero and neonate exposure to nonylphenol develops hyperadrenalism and metabolic syndrome later in life. I. First generation rats (F(1)).

    PubMed

    Chang, Ling-Ling; Wun, Wan-Song A; Wang, Paulus S

    2012-11-15

    Nonylphenol (NP) is an endocrine disruptor (ENDR). It is a chemical associated with the production and degradation of nonylphenol ethoxylates (NPE). NPE is widely used as nonionic surfactants. Previously, we observed that NP increased the production of corticosterone and aldosterone from zona fasciculata-reticularis, and zona glomerulosa cells, respectively. By the "fetal origins adult diseases" (Barker hypothesis), we examined the possible impact of NP exposure during developmental (in utero and neonatal) period with focus on disturbed adrenal function and related hyperadrenal syndrome, i.e. Cushings syndrome/metabolic syndrome. In this study, female rats drink NP water during pregnancy and lactation conferred F(1) generation: (1) increase the corticosterone, aldosterone concentration in plasma; (2) increase 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity in liver and adipose tissue; (3) increase aldosterone synthase activity in adrenal for adult offspring. Furthermore, it can increase body weight, adrenocorticotropin (ACTH) concentration in plasma, 11β-HSD1 protein expression in liver, steroidogenic acute regulatory (StAR) protein expression and 11β-hydroxylase activity in adrenal for male adult offspring. In summary, NP exposure during developmental period bestowed F(1) generation with hyperadrenalism and its consequence of metabolic syndrome.

  9. Extensive Frequency Comb Velocity Modulation Spectroscopy of ThF^+ for Use in the Jila Electron Edm Experiment

    NASA Astrophysics Data System (ADS)

    Gresh, Dan; Cossel, Kevin; Ye, Jun; Cornell, Eric

    2014-06-01

    The metastable ^3Δ_1 state in trapped HfF^+ is being used for an ongoing measurement of the electron electric dipole moment (eEDM) ThF^+, which has a larger effective electric field and a longer-lived ^3Δ_1 state, offers increased sensitivity for an eEDM measurement. Recently, the Heaven group has spectroscopically studied the low-lying states of ThF^+. However, to date there is no detailed information available about technically-accessible laser transitions in the near-infrared region of the spectrum, which are necessary for state preparation and detection in an eEDM experiment. By applying the technique of frequency comb velocity modulation spectroscopy (VMS) to ThF^+ we can acquire 150 cm-1 of continuous, ion-sensitive spectra with 150 MHz resolution in 25 minutes. Here, we report on extensive broadband, high-resolution survey spectroscopy of ThF^+ in the near-IR where we have observed and accurately fit several rovibronic transitions. In addition, we have observed and characterized numerous rovibronic transitions from an unknown thoriated species of molecular ions. H. Loh, K. C. Cossel, M. C. Grau, K.-K. Ni, E. R. Meyer, J. L. Bohn, J. Ye, E. A. Cornell, Science 342, 1220 (2013). B. J. Barker, I. O. Antonov, M. C. Heaven, K. A. Peterson, J. Chem. Phys. 136, 104305 (2012). L. C. Sinclair, K. C. Cossel, T. Coffey, J. Ye, E. A. Cornell, PRL 107, 093002 (2011).

  10. No, management is not a profession.

    PubMed

    Barker, Richard

    2010-01-01

    Because managers hold a status in society similar to that of doctors and lawyers, it is natural to think of business as a profession--and of business schools as professional schools. But, argues Barker, a professor at Cambridge University's Judge Business School, that can lead to inappropriate analysis and misguided perceptions. We turn to professionals for advice, he writes, because they have knowledge that we don't. We trust their advice because they've been guaranteed by professional associations that establish the boundaries of the field and reach consensus on what body of learning is required for formal training and certification. These associations make a market for professional services feasible. Although business schools might be able to reach consensus on what they should teach, the proper question is whether what they teach qualifies students to manage. After all, successful businesses are commonly run by people without MBAs. Managers' roles are inherently general, variable, and indefinable; their core skill is to integrate across functional areas, groups of people, and circumstances. Integration is learned in the minds of MBA students, whose experiences and careers are widely diverse, rather than taught in the content of program modules. Thus business education must be highly collaborative, with grading downplayed, and learning must differ according to the stage of a student's career. Business schools are not professional schools. They are incubators for business leadership.

  11. Gender differences in developmental programming of cardiovascular diseases.

    PubMed

    Dasinger, John Henry; Alexander, Barbara T

    2016-03-01

    Hypertension is a risk factor for cardiovascular disease, the leading cause of death worldwide. Although multiple factors contribute to the pathogenesis of hypertension, studies by Dr David Barker reporting an inverse relationship between birth weight and blood pressure led to the hypothesis that slow growth during fetal life increased blood pressure and the risk for cardiovascular disease in later life. It is now recognized that growth during infancy and childhood, in addition to exposure to adverse influences during fetal life, contributes to the developmental programming of increased cardiovascular risk. Numerous epidemiological studies support the link between influences during early life and later cardiovascular health; experimental models provide proof of principle and indicate that numerous mechanisms contribute to the developmental origins of chronic disease. Sex has an impact on the severity of cardiovascular risk in experimental models of developmental insult. Yet, few studies examine the influence of sex on blood pressure and cardiovascular health in low-birth weight men and women. Fewer still assess the impact of ageing on sex differences in programmed cardiovascular risk. Thus, the aim of the present review is to highlight current data about sex differences in the developmental programming of blood pressure and cardiovascular disease.

  12. Epigenetic and developmental influences on the risk of obesity, diabetes, and metabolic syndrome.

    PubMed

    Smith, Caitlin J; Ryckman, Kelli K

    2015-01-01

    Metabolic syndrome is a growing cause of morbidity and mortality worldwide. Metabolic syndrome is characterized by the presence of a variety of metabolic disturbances including obesity, hyperlipidemia, hypertension, and elevated fasting blood sugar. Although the risk for metabolic syndrome has largely been attributed to adult lifestyle factors such as poor nutrition, lack of exercise, and smoking, there is now strong evidence suggesting that predisposition to the development of metabolic syndrome begins in utero. First posited by Hales and Barker in 1992, the "thrifty phenotype" hypothesis proposes that susceptibility to adult chronic diseases can occur in response to exposures in the prenatal and perinatal periods. This hypothesis has been continually supported by epidemiologic studies and studies involving animal models. In this review, we describe the structural, metabolic and epigenetic changes that occur in response to adverse intrauterine environments including prenatal and postnatal diet, maternal obesity, and pregnancy complications. Given the increasing prevalence of metabolic syndrome in both the developed and developing worlds, a greater understanding and appreciation for the role of the intrauterine environment in adult chronic disease etiology is imperative.

  13. Developmental origins of health and disease: brief history of the approach and current focus on epigenetic mechanisms.

    PubMed

    Wadhwa, Pathik D; Buss, Claudia; Entringer, Sonja; Swanson, James M

    2009-09-01

    "Barker's hypothesis" emerged almost 25 years ago from epidemiological studies of birth and death records that revealed a high geographic correlation between rates of infant mortality and certain classes of later adult deaths as well as an association between birthweight and rates of adult death from ischemic heart disease. These observations led to a theory that undernutrition during gestation was an important early origin of adult cardiac and metabolic disorders due to fetal programming that permanently shaped the body's structure, function, and metabolism and contributed to adult disease. This theory stimulated interest in the fetal origins of adult disorders, which expanded and coalesced approximately 5 years ago with the formation of an international society for developmental origins of health and disease (DOHaD). Here we review a few examples of the many emergent themes of the DOHaD approach, including theoretical advances related to predictive adaptive responses of the fetus to a broad range of environmental cues, empirical observations of effects of overnutrition and stress during pregnancy on outcomes in childhood and adulthood, and potential epigenetic mechanisms that may underlie these observations and theory. Next, we discuss the relevance of the DOHaD approach to reproductive medicine. Finally, we consider the next steps that might be taken to apply, evaluate, and extend the DOHaD approach.

  14. Perinatal environment and its influences on metabolic programming of offspring.

    PubMed

    Tamashiro, Kellie L K; Moran, Timothy H

    2010-07-14

    The intrauterine environment supports the development and health of offspring. Perturbations to this environment can have detrimental effects on the fetus that have persistent pathological consequences through adolescence and adulthood. The developmental origins of the health and disease concept, also known as the "Barker Hypothesis", has been put forth to describe the increased incidence of chronic disease such as cardiovascular disease and diabetes in humans and animals exposed to a less than ideal intrauterine environment. Maternal infection, poor or excess nutrition, and stressful events can negatively influence the development of different cell types, tissues and organ systems ultimately predisposing the organism to pathological conditions. Although there are a variety of conditions associated to exposure to altered intrauterine environments, the focus of this review will be on the consequences of stress and high fat diet during the pre- and perinatal periods and associated outcomes related to obesity and other metabolic conditions. We further discuss possible neuroendocrine and epigenetic mechanisms responsible for the metabolic programming of offspring. The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009.

  15. Pharmacokinetics of a novel sublingual spray formulation of the antimalarial drug artemether in African children with malaria.

    PubMed

    Salman, Sam; Bendel, Daryl; Lee, Toong C; Templeton, David; Davis, Timothy M E

    2015-01-01

    The pharmacokinetics of sublingual artemether (ArTiMist) was investigated in 91 young African children with severe malaria or who could not tolerate oral antimalarial therapy. Each received 3.0 mg/kg of body weight of artemether at 0, 8, 24, 36, 48, and 60 h or until the initiation of oral treatment. Few blood samples were drawn postdose. Plasma artemether and dihydroartemisinin (DHA) levels were measured using liquid chromatography-mass spectrometry, and the data were analyzed using established population compartmental pharmacokinetic models. Parasite clearance was prompt (median parasite clearance time, 24 h), and there were no serious adverse events. Consistent with studies in healthy adults (S. Salman, D. Bendel, T. C. Lee, D. Templeton, and T. M. E. Davis, Antimicrob Agents Chemother 59:3197-3207, 2015, http://dx.doi.org/10.1128/AAC.05013-14), the absorption of sublingual artemether was biphasic, and multiple dosing was associated with the autoinduction of the metabolism of artemether to DHA (which itself has potent antimalarial activity). In contrast to studies using healthy volunteers, pharmacokinetic modeling indicated that the first absorption phase did not avoid first-pass metabolism, suggesting that the drug is transferred to the upper intestine through postdose fluid/food intake. Simulations using the present data and those from an earlier study in older Melanesian children with uncomplicated malaria treated with artemether-lumefantrine tablets suggested that the bioavailability of sublingual artemether was at least equivalent to that after conventional oral artemether-lumefantrine (median [interquartile range] areas under the concentration-time curve for artemether, 3,403 [2,471 to 4,771] versus 3,063 [2,358 to 4,514] μg · h/liter, respectively; and for DHA, 2,958 [2,146 to 4,278] versus 2,839 [1,812 to 3,488] μg · h/liter, respectively; P ≥ 0.42). These findings suggest that sublingual artemether could be used as prereferral treatment for sick

  16. A Lightweight, High-performance I/O Management Package for Data-intensive Computing

    SciTech Connect

    Wang, Jun

    2011-06-22

    Our group has been working with ANL collaborators on the topic bridging the gap between parallel file system and local file system during the course of this project period. We visited Argonne National Lab -- Dr. Robert Ross's group for one week in the past summer 2007. We looked over our current project progress and planned the activities for the incoming years 2008-09. The PI met Dr. Robert Ross several times such as HEC FSIO workshop 08, SC08 and SC10. We explored the opportunities to develop a production system by leveraging our current prototype to (SOGP+PVFS) a new PVFS version. We delivered SOGP+PVFS codes to ANL PVFS2 group in 2008.We also talked about exploring a potential project on developing new parallel programming models and runtime systems for data-intensive scalable computing (DISC). The methodology is to evolve MPI towards DISC by incorporating some functions of Google MapReduce parallel programming model. More recently, we are together exploring how to leverage existing works to perform (1) coordination/aggregation of local I/O operations prior to movement over the WAN, (2) efficient bulk data movement over the WAN, (3) latency hiding techniques for latency-intensive operations. Since 2009, we start applying Hadoop/MapReduce to some HEC applications with LANL scientists John Bent and Salman Habib. Another on-going work is to improve checkpoint performance at I/O forwarding Layer for the Road Runner super computer with James Nuetz and Gary Gridder at LANL. Two senior undergraduates from our research group did summer internships about high-performance file and storage system projects in LANL since 2008 for consecutive three years. Both of them are now pursuing Ph.D. degree in our group and will be 4th year in the PhD program in Fall 2011 and go to LANL to advance two above-mentioned works during this winter break. Since 2009, we have been collaborating with several computer scientists (Gary Grider, John bent, Parks Fields, James Nunez, Hsing

  17. Global stabilization using LSS-Theorem: Applications to Robotics and Aerospace Vehicles

    NASA Astrophysics Data System (ADS)

    Selman, AbdulRazzak

    Underactuated mechanical systems are gaining interest as they can sometimes provide the desired motion or functionality at reduced cost due to their using fewer expensive actuators. The term "underactuated" refers to the fact that such mechanical systems have fewer actuators than degrees of freedom, which makes them very difficult to control. Moreover, underactuated robots have nonlinear dynamics which must be tackled with nonlinear control techniques. Furthermore, control theory for underactuated mechanical systems has been an active area of research for the past 15-20 years. Most of the research has focused on local and global asymptotic stabilization by feedback. Underactuated systems can either possess nonminimum phase or minimum phase characteristics. For minimum phase underactuated systems, the stabilization problem is rather simple and many existing control design methodologies have been proved powerful in providing a solution to this problem. For nonminimum phase underactuated systems, asymptotic stabilization problem has been, and still is, an attractive subject to the researchers in the field of nonlinear control system and theory. In particular, global asymptotic stabilization (GAS) at a desired equilibrium point of such systems by means of a single smooth static or dynamic state feedback law is still largely an open problem in the literature. In this thesis, the problem of GAS via a smooth static state feedback law is addressed for a class of an underactuated nonlinear system that is affine (possibly non affine) in the control, partially feedback linearizable, nonminimum phase and (possibly) has a non-integrable acceleration constraint. The core result of the thesis is formulated through a theorem that the author refers to through this thesis as the Legend of Salah Salman (LSS) Theorem. LSS theorem states the existence of a smooth static state feedback law that globally asymptotically stabilizes the origin of the nonlinear underactuated system that is

  18. Abundance estimation and conservation biology

    USGS Publications Warehouse

    Nichols, J.D.; MacKenzie, D.I.

    2004-01-01

    Abundance is the state variable of interest in most population–level ecological research and in most programs involving management and conservation of animal populations. Abundance is the single parameter of interest in capture–recapture models for closed populations (e.g., Darroch, 1958; Otis et al., 1978; Chao, 2001). The initial capture–recapture models developed for partially (Darroch, 1959) and completely (Jolly, 1965; Seber, 1965) open populations represented efforts to relax the restrictive assumption of population closure for the purpose of estimating abundance. Subsequent emphases in capture–recapture work were on survival rate estimation in the 1970’s and 1980’s (e.g., Burnham et al., 1987; Lebreton et al.,1992), and on movement estimation in the 1990’s (Brownie et al., 1993; Schwarz et al., 1993). However, from the mid–1990’s until the present time, capture–recapture investigators have expressed a renewed interest in abundance and related parameters (Pradel, 1996; Schwarz & Arnason, 1996; Schwarz, 2001). The focus of this session was abundance, and presentations covered topics ranging from estimation of abundance and rate of change in abundance, to inferences about the demographic processes underlying changes in abundance, to occupancy as a surrogate of abundance. The plenary paper by Link & Barker (2004) is provocative and very interesting, and it contains a number of important messages and suggestions. Link & Barker (2004) emphasize that the increasing complexity of capture–recapture models has resulted in large numbers of parameters and that a challenge to ecologists is to extract ecological signals from this complexity. They offer hierarchical models as a natural approach to inference in which traditional parameters are viewed as realizations of stochastic processes. These processes are governed by hyperparameters, and the inferential approach focuses on these hyperparameters. Link & Barker (2004) also suggest that our attention

  19. Integrated magnetobiostratigraphy at the Oligocene/Miocene transition in the southwestern Atlantic Ocean (DSDP Leg 72, Hole 516F)

    NASA Astrophysics Data System (ADS)

    Gennari, Rocco; Persico, Davide; Florindo, Fabio; Turco, Elena; Villa, Giuliana

    2014-05-01

    A high-resolution integrated magnetostratigraphic and biostratigraphic (planktonic foraminifera and calcareous nannofossils) record of the interval encompassing the Oligocene/Miocene transition (OMT) at DSDP Hole 516F is here presented. This stratigraphic interval was previously studied by Berggren et al. (1983), Pujol (1983) and Spezzaferri (1994), although with a lower sample resolution. The magnetobiostratigraphic results of Berggren et al. (1983) are, moreover, considered as reference data for the age calibration of several bioevents along the OMT (Gradstein et al., 2012). Dealing with the same stratigraphic interval, other authors (Pagani et al., 2000; Plancq et al., 2012) based their paleoceanographic reconstruction on age model derived by Berggren et al. (1983). Our high-resolution integrated stratigraphy approach allowed us to obtain: 1) a more detailed succession of magnetic reversals across the OMT, including a better constraining of the base of Subchron C6Cn.2n, which formally defines the base of the Neogene (Steininger et al., 1997); 2) an integrated planktonic foraminifer and calcareous nannofossil quantitative biostratigraphy across the OMT. Particular focus has been addressed to the Lowest Common Occurrence of Paragloborotalia kugleri and the Highest Occurrences of Sphenolithus delphix and Sphenolithus capricornutus, which approximate the O/M boundary; 3) an updated age model of the OMT at Hole 516F. Finally, the new data here presented contributed to a critical review of the calcareous planktonic biostratigraphy across the OMT. References Berggren, W.A., Aubry, M.P. and Hamilton, N., 1983. Neogene magnetobiostratigraphy of deep sea drilling project site 516 (Rio Grande Rise, South Atlantic). In: Barker, P., et al. (Eds.), Initial Reports of the Deep Sea Drilling Project, 72, 675-713. Pagani, M., Arthur, M. A. and Freeman, K. H. 2000. Variations in Miocene phytoplankton growth rates in the southwest Atlantic: Evidence for changes in ocean circulation

  20. The lost church of Montemurro (Basilicata, Italy): Ground Penetrating Radar and Electrical Resistivity Tomography for detecting its buried remains in S. Maria Square.

    NASA Astrophysics Data System (ADS)

    Bavusi, Massimo; Giocoli, Alessandro; de Martino, Gregory; Loperte, Antonio; Lapenna, Vincenzo

    2010-05-01

    one in the central part and constituted by 48 electrodes 1 m spaced for a length of 47 m, allowed to investigate up to about 4.5 m. Both Wenner and dipole-dipole sequences gathered along two arrays were inverted by using Res2DInv software (Loke and Barker, 1996). They showed several shallow high resistive nuclei. Their positions are in good agreement with those of the reflectors showed in the radargrams and time slices. Joint interpretation of GPR and ERT results suggests the presence of cavities and manmade structures under the square. Acknowledgements This work was supported by the traffic policeman, the technicians, the workers and the mayor Mario Di Sanzio of the Commune of Montemurro. References Bavusi M., Chianese D., Giano S.I., Mucciarelli M. (2004). Multidisciplinary investigations on the Roman aqueduct of Grumentum (Basilicata, Southern Itlay). Annals of geophysics, 47 (6), 1791-1801. Cello G., , Tondi E., Micarelli L. and Mattioni L. (2003). Active tectonics and earthquake sources in the epicentral area of the 1857 Basilicata earthquake (southern Italy). Journal of Geodynamics, 36 (1,2), 37-50. Loke M.H., Barker R.D., (1996). Rapid least-square inversion of apparent resistivity pseudosections using a quasi-Newton method. Geophysical Prospecting, 44, 131 -152. Mallet R. (1862) - Great Neapolitan Earthquake of 1857. London 1862, 2, Chapmann and Hall.

  1. Seventeenth workshop on geothermal reservoir engineering: Proceedings

    SciTech Connect

    Ramey, H.J. Jr.; Kruger, P.; Miller, F.G.; Horne, R.N.; Brigham, W.E.; Cook, J.W.

    1992-01-31

    PREFACE The Seventeenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 29-31, 1992. There were one hundred sixteen registered participants which equaled the attendance last year. Participants were from seven foreign countries: Italy, Japan, United Kingdom, France, Belgium, Mexico and New Zealand. Performance of many geothermal fields outside the United States was described in the papers. The Workshop Banquet Speaker was Dr. Raffaele Cataldi. Dr. Cataldi gave a talk on the highlights of his geothermal career. The Stanford Geothermal Program Reservoir Engineering Award for Excellence in Development of Geothermal Energy was awarded to Dr. Cataldi. Dr. Frank Miller presented the award at the banquet. Thirty-eight papers were presented at the Workshop with two papers submitted for publication only. Dr. Roland Horne opened the meeting and the key note speaker was J.E. ''Ted'' Mock who discussed the DOE Geothermal R. & D. Program. The talk focused on aiding long-term, cost effective private resource development. Technical papers were organized in twelve sessions concerning: geochemistry, hot dry rock, injection, geysers, modeling, and reservoir mechanics. Session chairmen were major contributors to the program and we thank: Sabodh Garg., Jim Lovekin, Jim Combs, Ben Barker, Marcel Lippmann, Glenn Horton, Steve Enedy, and John Counsil. The Workshop was organized by the Stanford Geothermal Program faculty, staff, and graduate students. We wish to thank Pat Ota, Ted Sumida, and Terri A. Ramey who also produces the Proceedings Volumes for publication. We owe a great deal of thanks to our students who operate audiovisual equipment and to Francois Groff who coordinated the meeting arrangements for the Workshop. Henry J. Ramey, Jr. Roland N. Horne Frank G. Miller Paul Kruger William E. Brigham Jean W. Cook -vii

  2. Twenty-first workshop on geothermal reservoir engineering: Proceedings

    SciTech Connect

    1996-01-26

    PREFACE The Twenty-First Workshop on Geothermal Reservoir Engineering was held at the Holiday Inn, Palo Alto on January 22-24, 1996. There were one-hundred fifty-five registered participants. Participants came from twenty foreign countries: Argentina, Austria, Canada, Costa Rica, El Salvador, France, Iceland, Indonesia, Italy, Japan, Mexico, The Netherlands, New Zealand, Nicaragua, the Philippines, Romania, Russia, Switzerland, Turkey and the UK. The performance of many geothermal reservoirs outside the United States was described in several of the papers. Professor Roland N. Horne opened the meeting and welcomed visitors. The key note speaker was Marshall Reed, who gave a brief overview of the Department of Energy's current plan. Sixty-six papers were presented in the technical sessions of the workshop. Technical papers were organized into twenty sessions concerning: reservoir assessment, modeling, geology/geochemistry, fracture modeling hot dry rock, geoscience, low enthalpy, injection, well testing, drilling, adsorption and stimulation. Session chairmen were major contributors to the workshop, and we thank: Ben Barker, Bobbie Bishop-Gollan, Tom Box, Jim Combs, John Counsil, Sabodh Garg, Malcolm Grant, Marcel0 Lippmann, Jim Lovekin, John Pritchett, Marshall Reed, Joel Renner, Subir Sanyal, Mike Shook, Alfred Truesdell and Ken Williamson. Jim Lovekin gave the post-dinner speech at the banquet and highlighted the exciting developments in the geothermal field which are taking place worldwide. The Workshop was organized by the Stanford Geothermal Program faculty, staff, and graduate students. We wish to thank our students who operated the audiovisual equipment. Shaun D. Fitzgerald Program Manager.

  3. Professor Alan Turner (1947-2012). Specialist in Miocene-Pleistocene Carnivora, particularly Felidae and Hyaenidae and their palaeoecology

    NASA Astrophysics Data System (ADS)

    O'Regan, Hannah; Turner, Adam; Antón, Mauricio

    2014-07-01

    Alan first trained as a telecom engineer, working for the GPO (General Post Office) which later became British Telecom. He never forgot this early training and was fascinated by how things worked - always happy to take something apart and fix it (although his attempt to close a large plate glass window with a geological hammer was not one of his successes). Following a few years as an engineer, he went to Sheffield University to study archaeology as a mature student in 1973. At this time Sheffield was a hotbed of prehistory with Graeme Barker, Robin Dennell and many others contributing to a truly research-led degree (with tutorials in the pub (well, it was the 1970s)) (Fig. 1). Alan's interest in bones developed at this time, and having graduated in 1976 he went on to take a PhD, supervised by Robin Dennell, on "Aspects of the palaeoecology of large predators, including man, during the British Upper Pleistocene, with particular emphasis on predator-prey relationships" which resulted in a life-long interest in the Carnivora and particularly hyaenas. Following his PhD, Alan moved to the Environmental Archaeology Unit at York to undertake a Science Research Council project on the morphometrics of domestic cattle and pigs from Coppergate and other major urban excavations in the city. Faced with a lot of measurements and statistics, Alan retained his interest in the animals themselves. The project also confirmed to Alan that prehistory was his metier, rather than the historic periods. Former York colleagues still fondly recall Alan's dry wit, and the day that he successfully put the irritating lab telephone beyond use with no externally visible trace of damage.

  4. Plasma Physics Challenges of MM-to-THz and High Power Microwave Generation

    NASA Astrophysics Data System (ADS)

    Booske, John

    2007-11-01

    Homeland security and military defense technology considerations have stimulated intense interest in mobile, high power sources of millimeter-wave to terahertz regime electromagnetic radiation, from 0.1 to 10 THz. While sources at the low frequency end, i.e., the gyrotron, have been deployed or are being tested for diverse applications such as WARLOC radar and active denial systems, the challenges for higher frequency sources have yet to be completely met for applications including noninvasive sensing of concealed weapons and dangerous agents, high-data-rate communications, and high resolution spectroscopy and atmospheric sensing. The compact size requirements for many of these high frequency sources requires miniscule, micro-fabricated slow wave circuits with high rf ohmic losses. This necessitates electron beams with not only very small transverse dimensions but also very high current density for adequate gain. Thus, the emerging family of mm-to-THz e-beam-driven vacuum electronics devices share many of the same plasma physics challenges that currently confront ``classic'' high power microwave (HPM) generators [1] including bright electron sources, intense beam transport, energetic electron interaction with surfaces and rf air breakdown at output windows. Multidimensional theoretical and computational models are especially important for understanding and addressing these challenges. The contemporary plasma physics issues, recent achievements, as well as the opportunities and outlook on THz and HPM will be addressed. [1] R.J. Barker, J.H. Booske, N.C. Luhmann, and G.S. Nusinovich, Modern Microwave and Millimeter-Wave Power Electronics (IEEE/Wiley, 2005).

  5. Tidally Driven Dynamos in a Rotating Sphere

    NASA Astrophysics Data System (ADS)

    Cébron, D.; Hollerbach, R.

    2014-07-01

    Large-scale planetary or stellar magnetic fields generated by a dynamo effect are mostly attributed to flows forced by buoyancy forces in electrically conducting fluid layers. However, these large-scale fields may also be controlled by tides, as previously suggested for the star τ-boo, Mars, or the early Moon. By simulating a small local patch of a rotating fluid, Barker & Lithwick have recently shown that tides can drive small-scale dynamos by exciting a hydrodynamic instability, the so-called elliptical (or tidal) instability. By performing global magnetohydrodynamic simulations of a rotating spherical fluid body, we investigate if this instability can also drive the observed large-scale magnetic fields. We are thus interested in the dynamo threshold and the generated magnetic field in order to test if such a mechanism is relevant for planets and stars. Rather than solving the problem in a geometry deformed by tides, we consider a spherical fluid body and add a body force to mimic the tidal deformation in the bulk of the fluid. This allows us to use an efficient spectral code to solve the magnetohydrodynamic problem. We first compare the hydrodynamic results with theoretical asymptotic results and numerical results obtained in a truly deformed ellipsoid, which confirms the presence of elliptical instability. We then perform magnetohydrodynamic simulations and investigate the dynamo capability of the flow. Kinematic and self-consistent dynamos are finally simulated, showing that the elliptical instability is capable of generating a dipole-dominated large-scale magnetic field in global simulations of a fluid rotating sphere.

  6. Monitoring the geothermal fluid using time lapse electrical resistivity tomography: The Pisciarelli fumarolic field test site (Campi Flegrei, South Italy)

    NASA Astrophysics Data System (ADS)

    Fedele, Alessandro; Giulia Di Giuseppe, Maria; Troiano, Antonio; Somma, Reanto; Caputo, Teresa; Patella, Domenico; Troise, Claudia; De Natale, Giuseppe

    2015-04-01

    Pisciarelli area is a fumarolic field subject to very short time morphological changes. A number of critical problems affect this area, i.e. increase of temperature of the fumaroles above the average background temperature, local seismicity and occurrence of fumaroles mixed with jets of boiling water. The presence of a very shallow aquifer seem to have the control on the behavior and composition of the fumaroles. This fumarolic field is still largely unknown regarding geophysical surveys mainly because of its limited space, surrounded on the eastern side by intense urbanization inside the large Agnano crater (Troiano et al. 2014). Currently is mainly affected by geochemical, thermal and seismic monitoring which may not fully explain the behaviour of fluids surface. Many monitoring or time lapse (TL) applications are discussed in literature (e.g., White, 1994; Daily et al., 1995; Barker and Moore, 1998; Ramirez and Daily, 2001; Carter, 2002; Slater et al., 2002; Singha and Gorelick, 2005; Cassiani et al., 2006; Swarzenski et al., 2006; de Franco et al., 2009). However all these experiments are devoted to the use of the ERT for tracer tests or in contaminant hydrology and are characterized by a short monitoring period due to the complexity and problems of long-time instrument maintenance. We propose and present a first approach of a geophysical monitoring by time lapse electrical resistivity in a fumarolic field. The profiles were acquired in January 2013, in January, March, May, July, September and November 2014 respectively. They cross the Pisciarelli area following approximately the NS direction and were characterized by a 2.5 m electrode spacing and maximum penetration depth of about 20 m. and will supply fundamental evidences on the possible seasonal resistivity fluctuations or if the resistivity changes are indicative of an increase in volcanic gases present in the hydrothermal system.

  7. Assessing streamflow sensitivity to temperature increases in the Salmon River Basin, Idaho

    NASA Astrophysics Data System (ADS)

    Tang, Chunling; Crosby, Benjamin T.; Wheaton, Joseph M.; Piechota, Thomas C.

    2012-05-01

    Increased temperatures are occurring in the Salmon River Basin (SRB) of Idaho and are anticipated to continue increasing in the future, leading to complex changes in climate and water resources. To address these concerns, the objective of this study was to evaluate streamflow changes/sensitivity when temperatures increase. A hydrological model, the Variable Infiltration Capacity (VIC) model, was applied to simulate streamflow under thirty temperature increase scenarios (i.e., rising 0.1 °C per step to 3 °C). It was found that the annual mean streamflow decreased whenever temperatures increased in the SRB. Streamflow increases in winter and decreases in spring and summer but is barely affected by temperature in autumn. On a monthly basis, streamflow responses varied in response to rising temperatures. When temperature increased, the streamflow increase occurred from November to February, and it decreased from May to July. The analysis also discovered linear relationships between rising temperatures and streamflow changes throughout the year, with the exception of June and July, which revealed logarithmic correlations. Results obtained by daily streamflow analysis showed that center time occurred 10-30 d earlier when temperatures increased 2 °C and 15-45 d earlier when temperatures increased 3 °C. Finally, the Richards-Barker Index (R-B Index), a flashiness index, also increased with rising temperatures, and a higher R-B Index causes bank erosion problems. Changes in the streamflow due to the temperature increases have a significant implication both for the water management and ecological processes.

  8. Density functional theory for the description of spherical non-associating monomers in confined media using the SAFT-VR equation of state and weighted density approximations

    NASA Astrophysics Data System (ADS)

    Malheiro, Carine; Mendiboure, Bruno; Plantier, Frédéric; Blas, Felipe J.; Miqueu, Christelle

    2014-04-01

    As a first step of an ongoing study of thermodynamic properties and adsorption of complex fluids in confined media, we present a new theoretical description for spherical monomers using the Statistical Associating Fluid Theory for potential of Variable Range (SAFT-VR) and a Non-Local Density Functional Theory (NLDFT) with Weighted Density Approximations (WDA). The well-known Modified Fundamental Measure Theory is used to describe the inhomogeneous hard-sphere contribution as a reference for the monomer and two WDA approaches are developed for the dispersive terms from the high-temperature Barker and Henderson perturbation expansion. The first approach extends the dispersive contributions using the scalar and vector weighted densities introduced in the Fundamental Measure Theory (FMT) and the second one uses a coarse-grained (CG) approach with a unique weighted density. To test the accuracy of this new NLDFT/SAFT-VR coupling, the two versions of the theoretical model are compared with Grand Canonical Monte Carlo (GCMC) molecular simulations using the same molecular model. Only the version with the "CG" approach for the dispersive terms provides results in excellent agreement with GCMC calculations in a wide range of conditions while the "FMT" extension version gives a good representation solely at low pressures. Hence, the "CG" version of the theoretical model is used to reproduce methane adsorption isotherms in a Carbon Molecular Sieve and compared with experimental data after a characterization of the material. The whole results show an excellent agreement between modeling and experiments. Thus, through a complete and consistent comparison both with molecular simulations and with experimental data, the NLDFT/SAFT-VR theory has been validated for the description of monomers.

  9. Semiclassical approach to model quantum fluids using the statistical associating fluid theory for systems with potentials of variable range

    NASA Astrophysics Data System (ADS)

    Trejos, Víctor M.; Gil-Villegas, Alejandro

    2012-05-01

    Thermodynamic properties of quantum fluids are described using an extended version of the statistical associating fluid theory for potentials of variable range (SAFT-VR) that takes into account quantum corrections to the Helmholtz free energy A, based on the Wentzel-Kramers-Brillouin approximation. We present the theoretical background of this approach (SAFT-VRQ), considering two different cases depending on the continuous or discontinuous nature of the particles pair interaction. For the case of continuous potentials, we demonstrate that the standard Wigner-Kirkwood theory for quantum fluids can be derived from the de Broglie-Bohm formalism for quantum mechanics that can be incorporated within the Barker and Henderson perturbation theory for liquids in a straightforward way. When the particles interact via a discontinuous pair potential, the SAFT-VR method can be combined with the perturbation theory developed by Singh and Sinha [J. Chem. Phys. 67, 3645 (1977); Singh and Sinha J. Chem. Phys. 68, 562 (1978)]. We present an analytical expression for the first-order quantum perturbation term for a square-well potential, and the theory is applied to model thermodynamic properties of hydrogen, deuterium, neon, and helium-4. Vapor-liquid equilibrium, liquid and vapor densities, isochoric and isobaric heat capacities, Joule-Thomson coefficients and inversion curves are predicted accurately with respect to experimental data. We find that quantum corrections are important for the global behavior of properties of these fluids and not only for the low-temperature regime. Predictions obtained for hydrogen compare very favorably with respect to cubic equations of state.

  10. A meteor head echo analysis algorithm for the lower VHF band

    NASA Astrophysics Data System (ADS)

    Kero, J.; Szasz, C.; Nakamura, T.; Terasawa, T.; Miyamoto, H.; Nishimura, K.

    2012-04-01

    We have developed an automated analysis scheme for meteor head echo observations by the 46.5 MHz Middle and Upper atmosphere (MU) radar near Shigaraki, Japan (34.85° N, 136.10° E). The analysis procedure computes meteoroid range, velocity and deceleration as functions of time with unprecedented accuracy and precision. This is crucial for estimations of meteoroid mass and orbital parameters as well as investigations of the meteoroid-atmosphere interaction processes. In this paper we present this analysis procedure in detail. The algorithms use a combination of single-pulse-Doppler, time-of-flight and pulse-to-pulse phase correlation measurements to determine the radial velocity to within a few tens of metres per second with 3.12 ms time resolution. Equivalently, the precision improvement is at least a factor of 20 compared to previous single-pulse measurements. Such a precision reveals that the deceleration increases significantly during the intense part of a meteoroid's ablation process in the atmosphere. From each received pulse, the target range is determined to within a few tens of meters, or the order of a few hundredths of the 900 m long range gates. This is achieved by transmitting a 13-bit Barker code oversampled by a factor of two at reception and using a novel range interpolation technique. The meteoroid velocity vector is determined from the estimated radial velocity by carefully taking the location of the meteor target and the angle from its trajectory to the radar beam into account. The latter is determined from target range and bore axis offset. We have identified and solved the signal processing issue giving rise to the peculiar signature in signal to noise ratio plots reported by Galindo et al. (2011), and show how to use the range interpolation technique to differentiate the effect of signal processing from physical processes.

  11. An analytical equation of state for describing isotropic-nematic phase equilibria of Lennard-Jones chain fluids with variable degree of molecular flexibility

    NASA Astrophysics Data System (ADS)

    van Westen, Thijs; Oyarzún, Bernardo; Vlugt, Thijs J. H.; Gross, Joachim

    2015-06-01

    We develop an equation of state (EoS) for describing isotropic-nematic (IN) phase equilibria of Lennard-Jones (LJ) chain fluids. The EoS is developed by applying a second order Barker-Henderson perturbation theory to a reference fluid of hard chain molecules. The chain molecules consist of tangentially bonded spherical segments and are allowed to be fully flexible, partially flexible (rod-coil), or rigid linear. The hard-chain reference contribution to the EoS is obtained from a Vega-Lago rescaled Onsager theory. For the description of the (attractive) dispersion interactions between molecules, we adopt a segment-segment approach. We show that the perturbation contribution for describing these interactions can be divided into an "isotropic" part, which depends only implicitly on orientational ordering of molecules (through density), and an "anisotropic" part, for which an explicit dependence on orientational ordering is included (through an expansion in the nematic order parameter). The perturbation theory is used to study the effect of chain length, molecular flexibility, and attractive interactions on IN phase equilibria of pure LJ chain fluids. Theoretical results for the IN phase equilibrium of rigid linear LJ 10-mers are compared to results obtained from Monte Carlo simulations in the isobaric-isothermal (NPT) ensemble, and an expanded formulation of the Gibbs-ensemble. Our results show that the anisotropic contribution to the dispersion attractions is irrelevant for LJ chain fluids. Using the isotropic (density-dependent) contribution only (i.e., using a zeroth order expansion of the attractive Helmholtz energy contribution in the nematic order parameter), excellent agreement between theory and simulations is observed. These results suggest that an EoS contribution for describing the attractive part of the dispersion interactions in real LCs can be obtained from conventional theoretical approaches designed for isotropic fluids, such as a Perturbed

  12. On the vapor-liquid equilibrium of attractive chain fluids with variable degree of molecular flexibility

    NASA Astrophysics Data System (ADS)

    van Westen, Thijs; Vlugt, Thijs J. H.; Gross, Joachim

    2015-06-01

    We study the isotropic (vapor and liquid) phase behavior of attractive chain fluids. Special emphasis is placed on the role of molecular flexibility, which is studied by means of a rod-coil model. Two new equations of state (EoSs) are developed for square-well- (SW) and Lennard-Jones (LJ) chain fluids. The EoSs are developed by applying the perturbation theory of Barker and Henderson (BH) to a reference fluid of hard chain molecules. The novelty of the approach is based on (1) the use of a recently developed hard-chain reference EoS that explicitly incorporates the effects of molecular flexibility, (2) the use of recent molecular simulation data for the radial distribution function of hard-chain fluids, and (3) a newly developed effective segment size, which effectively accounts for the soft repulsion between segments of LJ chains. It is shown that the effective segment size needs to be temperature-, density-, and chain-length dependent. To obtain a simplified analytical EoS, the perturbation terms are fitted by polynomials in density (SW and LJ), chain length (SW and LJ), and temperature (only for LJ). It is shown that the equations of state result in an accurate description of molecular simulation data for vapor-liquid equilibria (VLE) and isotherms of fully flexible SW- and LJ chain fluids and their mixtures. To evaluate the performance of the equations of state in describing the effects of molecular flexibility on VLE, we present new Monte Carlo simulation results for the VLE of rigid linear- and partially flexible SW- and LJ chain fluids. For SW chains, the developed EoS is in a good agreement with simulation results. For increased rigidity of the chains, both theory and simulations predict an increase of the VL density difference and a slight increase of the VL critical temperature. For LJ chains, the EoS proves incapable of reproducing part of these trends.

  13. The coupled effect of tides and stellar winds on the evolution of compact binaries

    NASA Astrophysics Data System (ADS)

    Repetto, Serena; Nelemans, Gijs

    2014-10-01

    We follow the evolution of compact binaries under the coupled effect of tides and stellar winds until the onset of Roche lobe overflow. These binaries contain a compact object (either a black hole, a neutron star or a planet) and a stellar component. We integrate the full set of tidal equations, which are based on Hut's model for tidal evolution, and we couple them with the angular momentum loss in a stellar wind. Our aim is twofold. First, we wish to highlight some interesting evolutionary outcomes of the coupling. When tides are coupled with a non-massive stellar wind, one interesting outcome is that in certain types of binaries, the stellar spin tends to reach a quasi-equilibrium state, where the effects of tides and wind are counteracting each other. When tides are coupled with a massive wind, we parametrize the evolution in terms of the decoupling radius, at which the wind decouples from the star. Even for small decoupling radii, this wind braking can drive systems on the main sequence to Roche lobe overflow that otherwise would fail to do so. Our second aim is to inspect whether simple time-scale considerations are a good description of the evolution of the systems. We find that simple time-scale considerations, which rely on neglecting the coupling between tides and stellar winds, do not accurately represent the true evolution of compact binaries. The outcome of the coupled evolution of the rotational and orbital elements can strongly differ from simple time-scale considerations, as already pointed out by Barker and Ogilvie in the case of short-period planetary systems.

  14. TIDALLY DRIVEN DYNAMOS IN A ROTATING SPHERE

    SciTech Connect

    Cébron, D.; Hollerbach, R. E-mail: r.hollerbach@leeds.ac.uk

    2014-07-01

    Large-scale planetary or stellar magnetic fields generated by a dynamo effect are mostly attributed to flows forced by buoyancy forces in electrically conducting fluid layers. However, these large-scale fields may also be controlled by tides, as previously suggested for the star τ-boo, Mars, or the early Moon. By simulating a small local patch of a rotating fluid, Barker and Lithwick have recently shown that tides can drive small-scale dynamos by exciting a hydrodynamic instability, the so-called elliptical (or tidal) instability. By performing global magnetohydrodynamic simulations of a rotating spherical fluid body, we investigate if this instability can also drive the observed large-scale magnetic fields. We are thus interested in the dynamo threshold and the generated magnetic field in order to test if such a mechanism is relevant for planets and stars. Rather than solving the problem in a geometry deformed by tides, we consider a spherical fluid body and add a body force to mimic the tidal deformation in the bulk of the fluid. This allows us to use an efficient spectral code to solve the magnetohydrodynamic problem. We first compare the hydrodynamic results with theoretical asymptotic results and numerical results obtained in a truly deformed ellipsoid, which confirms the presence of elliptical instability. We then perform magnetohydrodynamic simulations and investigate the dynamo capability of the flow. Kinematic and self-consistent dynamos are finally simulated, showing that the elliptical instability is capable of generating a dipole-dominated large-scale magnetic field in global simulations of a fluid rotating sphere.

  15. Inference for occupancy and occupancy dynamics

    USGS Publications Warehouse

    O'Connell, Allan F.; Bailey, Larissa L.; O'Connell, Allan F.; Nichols, James D.; Karanth, K. Ullas

    2011-01-01

    This chapter deals with the estimation of occupancy as a state variable to assess the status of, and track changes in, species distributions when sampling with camera traps. Much of the recent interest in occupancy estimation and modeling originated from the models developed by MacKenzie et al. (2002, 2003), although similar methods were developed independently (Azuma et al. 1990; Bayley and Petersen 2001; Nichols and Karanth, 2002; Tyre et al. 2003), all of which deal with species occurrence information and imperfect detection. Less than a decade after these publications, the modeling and estimation of species occurrence and occupancy dynamics have increased significantly. Special features of scientific journals have explored innovative uses of detection–nondetection data with occupancy models (Vojta 2005), and an entire volume has synthesized the use and application of occupancy estimation methods (MacKenzie et al. 2006). Reviews of the topical concepts, philosophical considerations, and various sampling designs that can be used for occupancy estimation are now readily available for a range of audiences (MacKenzie and Royle 2005; MacKenzie et al. 2006; Bailey et al. 2007; Royle and Dorazio 2008; Conroy and Carroll 2009; Kendall and White 2009; Hines et al. 2010; Link and Barker 2010). As a result, it would be pointless here to recast all that these publications have so eloquently articulated, but that said, a review of any scientific topic requires sufficient context and relevant background information, especially when relatively new methodologies and techniques such as occupancy estimation and camera traps are involved. This is especially critical in a digital age where new information is published at warp speed, making it increasingly difficult to stay abreast of theoretical advances and research developments.

  16. Broadband Velocity Modulation Spectroscopy of Molecular Ions for Use in the Jila Electron Edm Experiment

    NASA Astrophysics Data System (ADS)

    Gresh, Daniel N.; Cossel, Kevin C.; Cornell, Eric A.; Ye, Jun

    2013-06-01

    The JILA electron electric dipole moment (eEDM) experiment will use a low-lying, metastable ^3Δ_1 state in trapped molecular ions of HfF^+ or ThF^+. Prior to this work, the low-lying states of these molecules had been investigated by PFI-ZEKE spectroscopy. However, there were no detailed studies of the electronic structure. The recently developed technique of frequency comb velocity modulation spectroscopy (VMS) provides broad-bandwidth, high-resolution, ion-sensitive spectroscopy, allowing the acquisition of 150 cm^{-1} of continuous spectra in 30 minutes over 1500 simultaneous channels. By supplementing this technique with cw-laser VMS, we have investigated the electronic structure of HfF^+ in the frequency range of 9950 to 14600 cm^{-1}, accurately fitting and assigning 16 rovibronic transitions involving 8 different electronic states including the X^1Σ^+ and a^3Δ_1 states. In addition, an observed ^3Π_{0+} state with coupling to both the X and a states has been used in the actual eEDM experiment to coherently transfer population from the rovibronic ground state of HfF^+ to the eEDM science state. Furthermore, we report on current efforts of applying frequency comb VMS at 700 - 900 nm to the study of ThF^+, which has a lower energy ^3Δ_1 state and a greater effective electric field, and will provide increased sensitivity for a measurement of the eEDM. A. E. Leanhardt et. al., Journal of Molecular Spectroscopy 270, 1-25 (2011). B. J. Barker, I. O. Antonov, M. C. Heaven, K. A. Peterson, Journal of Chemical Physics 136, 104305 (2012). L. C. Sinclair, K. C. Cossel, T. Coffey, J. Ye, E. A. Cornell, Physical Review Letters 107, 093002 (2011). K.C. Cossel et. al., Chemical Physics Letters 546, 1-11 (2012).

  17. Broadband Frequency Comb and Cw-Laser Velocity Modulation Spectroscopy of ThF+

    NASA Astrophysics Data System (ADS)

    Gresh, Dan; Cossel, Kevin; Ye, Jun; Cornell, Eric

    2015-06-01

    An experimental search for the permanent electric dipole moment of the electron (eEDM) is currently being performed using the metastable ^3Δ_1 state in trapped HfF^+ ^(^). The use of ThF^+ could significantly increase the sensitivity due to the larger effective electric field and longer ^3Δ_1 state lifetime. Previous work by the Heaven group has identified several low-lying ThF^+ electronic states; however, the ground state could not be conclusively assigned. In addition, transitions to intermediate electronic states have not been identified, but they are necessary for state detection, manipulation, and readout in an eEDM experiment. To date we have acquired 3700 wn of densely-sampled ThF^+ spectra in the 695 - 1020 nm region with frequency comb and cw-laser velocity modulation spectroscopy. With high resolution, we have accurately fit more than 20 ThF^+ vibronic transitions, including electronic states spaced by the known X-a energy separation^b. We will report on the ThF^+ ground state assignment and its implications for an eEDM experiment. H. Loh, K. C. Cossel, M. C. Grau, K.-K. Ni, E. R. Meyer, J. L. Bohn, J. Ye, E. A. Cornell, Science 342, 1220 (2013). B. J. Barker, I. O. Antonov, M. C. Heaven, K. A. Peterson, J. Chem. Phys. 136, 104305 (2012). L. C. Sinclair, K. C. Cossel, T. Coffey, J. Ye, E. A. Cornell, PRL 107, 093002 (2011). K.C. Cossel et. al., Chem. Phys. Lett. 546, 1 (2012).

  18. Critical wind velocity for arresting upwind gas and smoke dispersion induced by near-wall fire in a road tunnel.

    PubMed

    Hu, L H; Peng, W; Huo, R

    2008-01-15

    In case of a tunnel fire, toxic gas and smoke particles released are the most fatal contaminations. It is important to supply fresh air from the upwind side to provide a clean and safe environment upstream from the fire source for people evacuation. Thus, the critical longitudinal wind velocity for arresting fire induced upwind gas and smoke dispersion is a key criteria for tunnel safety design. Former studies and thus, the models built for estimating the critical wind velocity are all arbitrarily assuming that the fire takes place at the centre of the tunnel. However, in many real cases in road tunnels, the fire originates near the sidewall. The critical velocity of a near-wall fire should be different with that of a free-standing central fire due to their different plume entrainment process. Theoretical analysis and CFD simulation were performed in this paper to estimate the critical velocity for the fire near the sidewall. Results showed that when fire originates near the sidewall, it needs larger critical velocity to arrest the upwind gas and smoke dispersion than when fire at the centre. The ratio of critical velocity of a near-wall fire to that of a central fire was ideally estimated to be 1.26 by theoretical analysis. Results by CFD modelling showed that the ratio decreased with the increase of the fire size till near to unity. The ratio by CFD modelling was about 1.18 for a 500kW small fire, being near to and a bit lower than the theoretically estimated value of 1.26. However, the former models, including those of Thomas (1958, 1968), Dangizer and Kenndey (1982), Oka and Atkinson (1995), Wu and Barker (2000) and Kunsch (1999, 2002), underestimated the critical velocity needed for a fire near the tunnel sidewall.

  19. Alcohol-Induced Developmental Origins of Adult-Onset Diseases.

    PubMed

    Lunde, Emilie R; Washburn, Shannon E; Golding, Michael C; Bake, Shameena; Miranda, Rajesh C; Ramadoss, Jayanth

    2016-07-01

    Fetal alcohol exposure may impair growth, development, and function of multiple organ systems and is encompassed by the term fetal alcohol spectrum disorders (FASD). Research has so far focused on the mechanisms, prevention, and diagnosis of FASD, while the risk for adult-onset chronic diseases in individuals exposed to alcohol in utero is not well explored. David Barker's hypothesis on Developmental Origins of Health and Disease (DOHaD) suggests that insults to the milieu of the developing fetus program it for adult development of chronic diseases. In the 25 years since the introduction of this hypothesis, epidemiological and animal model studies have made significant advancements in identifying in utero developmental origins of chronic adult-onset diseases affecting cardiovascular, endocrine, musculoskeletal, and psychobehavioral systems. Teratogen exposure is an established programming agent for adult diseases, and recent studies suggest that prenatal alcohol exposure correlates with adult onset of neurobehavioral deficits, cardiovascular disease, endocrine dysfunction, and nutrient homeostasis instability, warranting additional investigation of alcohol-induced DOHaD, as well as patient follow-up well into adulthood for affected individuals. In utero epigenetic alterations during critical periods of methylation are a key potential mechanism for programming and susceptibility of adult-onset chronic diseases, with imprinted genes affecting metabolism being critical targets. Additional studies in epidemiology, phenotypic characterization in response to timing, dose, and duration of exposure, as well as elucidation of mechanisms underlying FASD-DOHaD inter relation, are thus needed to clinically define chronic disease associated with prenatal alcohol exposure. These studies are critical to establish interventional strategies that decrease incidence of these adult-onset diseases and promote healthier aging among individuals affected with FASD. PMID:27254466

  20. A complex of species related to Paradiscogaster glebulae (Digenea: Faustulidae) in chaetodontid fishes (Teleostei: Perciformes) of the Great Barrier Reef.

    PubMed

    Diaz, Pablo E; Bray, Rodney A; Cutmore, Scott C; Ward, Selina; Cribb, Thomas H

    2015-10-01

    A total of 1523 individuals of 34 species of chaetodontids from the Great Barrier Reef were examined for faustulid trematodes. Specimens resembling Paradiscogaster glebulae Bray, Cribb & Barker, 1994 were found in nine chaetodontid species at three localities. These specimens are shown, on the basis of combined morphological and molecular analyses, to comprise a complex of morphologically similar and partly cryptic species. The complex may comprise as many as six distinct species of which three are resolved here. The true P. glebulae is identified in Chaetodon ornatissimus Cuvier, 1831, Chaetodon aureofasciatus Macleay, 1878, Chaetodon plebeius Cuvier, 1831, Chaetodon rainfordi McCulloch, 1923 and Chaetodon speculum Cuvier, 1831. Two new species are described, Paradiscogaster munozae n. sp. from Heniochus varius (Cuvier, 1829), Heniochus chrysostomus Cuvier, 1831 and Chaetodon citrinellus Cuvier, 1831 and Paradiscogaster melendezi n. sp. from Chaetodon kleinii Bloch, 1790. In terms of morphology the three species differ most clearly in the development of the appendages on the ventral sucker. The three species differ at 3-6consistent bp of ITS2 rDNA. The host-specificity of the three species differs strikingly. P. melendezi n. sp. infects just one fish species, P. glebulae infects species of only one clade of Chaetodon, and P. munozae n. sp. infects quite unrelated species. The basis of this unusual pattern of host-specificity requires further exploration. Two of the species recognised here, P. glebulae and P. munozae n. sp., showed apparent intra-individual variation in the ITS2 rDNA sequences as demonstrated by clear, replicated double peaks in the electropherograms.

  1. Net charge changes in the calculation of relative ligand-binding free energies via classical atomistic molecular dynamics simulation.

    PubMed

    Reif, Maria M; Oostenbrink, Chris

    2014-01-30

    The calculation of binding free energies of charged species to a target molecule is a frequently encountered problem in molecular dynamics studies of (bio-)chemical thermodynamics. Many important endogenous receptor-binding molecules, enzyme substrates, or drug molecules have a nonzero net charge. Absolute binding free energies, as well as binding free energies relative to another molecule with a different net charge will be affected by artifacts due to the used effective electrostatic interaction function and associated parameters (e.g., size of the computational box). In the present study, charging contributions to binding free energies of small oligoatomic ions to a series of model host cavities functionalized with different chemical groups are calculated with classical atomistic molecular dynamics simulation. Electrostatic interactions are treated using a lattice-summation scheme or a cutoff-truncation scheme with Barker-Watts reaction-field correction, and the simulations are conducted in boxes of different edge lengths. It is illustrated that the charging free energies of the guest molecules in water and in the host strongly depend on the applied methodology and that neglect of correction terms for the artifacts introduced by the finite size of the simulated system and the use of an effective electrostatic interaction function considerably impairs the thermodynamic interpretation of guest-host interactions. Application of correction terms for the various artifacts yields consistent results for the charging contribution to binding free energies and is thus a prerequisite for the valid interpretation or prediction of experimental data via molecular dynamics simulation. Analysis and correction of electrostatic artifacts according to the scheme proposed in the present study should therefore be considered an integral part of careful free-energy calculation studies if changes in the net charge are involved.

  2. Fast Gamma Rhythms in the Hippocampus Promote Encoding of Novel Object–Place Pairings123

    PubMed Central

    Wood Bieri, Kevin; Hwaun, Ernie

    2016-01-01

    Abstract Hippocampal gamma rhythms increase during mnemonic operations (Johnson and Redish, 2007; Montgomery and Buzsáki, 2007; Sederberg et al., 2007; Jutras et al., 2009; Trimper et al., 2014) and may affect memory encoding by coordinating activity of neurons that code related information (Jensen and Lisman, 2005). Here, a hippocampal-dependent, object–place association task (Clark et al., 2000; Broadbent et al., 2004; Eacott and Norman, 2004; Lee et al., 2005; Winters et al., 2008; Barker and Warburton, 2011) was used in rats to investigate how slow and fast gamma rhythms in the hippocampus relate to encoding of memories for novel object–place associations. In novel object tasks, the degree of hippocampal dependence has been reported to vary depending on the type of novelty (Eichenbaum et al., 2007; Winters et al., 2008). Therefore, gamma activity was examined during three novelty conditions: a novel object presented in a location where a familiar object had been (NO), a familiar object presented in a location where no object had been (NL), and a novel object presented in a location where no object had been (NO+NL). The strongest and most consistent effects were observed for fast gamma rhythms during the NO+NL condition. Fast gamma power, CA3–CA1 phase synchrony, and phase-locking of place cell spikes increased during exploration of novel, compared to familiar, object–place associations. Additionally, place cell spiking during exploration of novel object–place pairings was increased when fast gamma rhythms were present. These results suggest that fast gamma rhythms promote encoding of memories for novel object–place associations. PMID:27257621

  3. Alcohol-Induced Developmental Origins of Adult-Onset Diseases.

    PubMed

    Lunde, Emilie R; Washburn, Shannon E; Golding, Michael C; Bake, Shameena; Miranda, Rajesh C; Ramadoss, Jayanth

    2016-07-01

    Fetal alcohol exposure may impair growth, development, and function of multiple organ systems and is encompassed by the term fetal alcohol spectrum disorders (FASD). Research has so far focused on the mechanisms, prevention, and diagnosis of FASD, while the risk for adult-onset chronic diseases in individuals exposed to alcohol in utero is not well explored. David Barker's hypothesis on Developmental Origins of Health and Disease (DOHaD) suggests that insults to the milieu of the developing fetus program it for adult development of chronic diseases. In the 25 years since the introduction of this hypothesis, epidemiological and animal model studies have made significant advancements in identifying in utero developmental origins of chronic adult-onset diseases affecting cardiovascular, endocrine, musculoskeletal, and psychobehavioral systems. Teratogen exposure is an established programming agent for adult diseases, and recent studies suggest that prenatal alcohol exposure correlates with adult onset of neurobehavioral deficits, cardiovascular disease, endocrine dysfunction, and nutrient homeostasis instability, warranting additional investigation of alcohol-induced DOHaD, as well as patient follow-up well into adulthood for affected individuals. In utero epigenetic alterations during critical periods of methylation are a key potential mechanism for programming and susceptibility of adult-onset chronic diseases, with imprinted genes affecting metabolism being critical targets. Additional studies in epidemiology, phenotypic characterization in response to timing, dose, and duration of exposure, as well as elucidation of mechanisms underlying FASD-DOHaD inter relation, are thus needed to clinically define chronic disease associated with prenatal alcohol exposure. These studies are critical to establish interventional strategies that decrease incidence of these adult-onset diseases and promote healthier aging among individuals affected with FASD.

  4. On the vapor-liquid equilibrium of attractive chain fluids with variable degree of molecular flexibility.

    PubMed

    van Westen, Thijs; Vlugt, Thijs J H; Gross, Joachim

    2015-06-14

    We study the isotropic (vapor and liquid) phase behavior of attractive chain fluids. Special emphasis is placed on the role of molecular flexibility, which is studied by means of a rod-coil model. Two new equations of state (EoSs) are developed for square-well- (SW) and Lennard-Jones (LJ) chain fluids. The EoSs are developed by applying the perturbation theory of Barker and Henderson (BH) to a reference fluid of hard chain molecules. The novelty of the approach is based on (1) the use of a recently developed hard-chain reference EoS that explicitly incorporates the effects of molecular flexibility, (2) the use of recent molecular simulation data for the radial distribution function of hard-chain fluids, and (3) a newly developed effective segment size, which effectively accounts for the soft repulsion between segments of LJ chains. It is shown that the effective segment size needs to be temperature-, density-, and chain-length dependent. To obtain a simplified analytical EoS, the perturbation terms are fitted by polynomials in density (SW and LJ), chain length (SW and LJ), and temperature (only for LJ). It is shown that the equations of state result in an accurate description of molecular simulation data for vapor-liquid equilibria (VLE) and isotherms of fully flexible SW- and LJ chain fluids and their mixtures. To evaluate the performance of the equations of state in describing the effects of molecular flexibility on VLE, we present new Monte Carlo simulation results for the VLE of rigid linear- and partially flexible SW- and LJ chain fluids. For SW chains, the developed EoS is in a good agreement with simulation results. For increased rigidity of the chains, both theory and simulations predict an increase of the VL density difference and a slight increase of the VL critical temperature. For LJ chains, the EoS proves incapable of reproducing part of these trends.

  5. Extension of the AURIC Radiative Transfer Model for Mars Atmospheric Research

    NASA Astrophysics Data System (ADS)

    Evans, J. S.; Lumpe, J. D.; Correira, J.; Stewart, A. I.; Schneider, N. M.; Deighan, J.

    2013-12-01

    We present recent updates to the Atmospheric Ultraviolet Radiance Integrated Code (AURIC) model that allow it to be used as a forward model for Mars atmospheric research. AURIC is a state of the art far ultraviolet (FUV) to near-infrared (NIR) atmospheric radiance model that has been used extensively for analysis and modeling of terrestrial upper atmospheric remote sensing data. We present recent updates to the Atmospheric Ultraviolet Radiance Integrated Code (AURIC) model that allow it to be used as a forward model for Mars atmospheric research. AURIC is a state of the art far ultraviolet (FUV) to near-infrared (NIR) atmospheric radiance model that has been used extensively for analysis and modeling of terrestrial upper atmospheric remote sensing data. The airglow modeling capabilities of AURIC make it a powerful tool that can be used to characterize optical backgrounds, simulate data from both rocket and satellite-borne optical instrumentation, and serve as a forward model driver for geophysical retrieval algorithms. Upgrades made to allow modeling of the Martian atmosphere include 1-D Mars photochemistry and molecular transport and the addition of the following molecular band systems: CO Cameron; CO Fourth Positive Group; CO2+ Fox-Duffendack-Barker; CO2+ UV Doublet; CO Hopfield-Birge (B-X); and CO+ First Negative Group. Furthermore, a prototype AURIC-Titan model has also been developed, allowing comparison of AURIC spectral radiances with Cassini-Huygens/UVIS data [Stevens et al., 2011; Stevens et al., in preparation]. Extension of AURIC to the atmospheres of Pluto and it's largest moon, Charon, is also ongoing in support of NASA's New Horizons mission [Stevens, Evans, and Gladstone, 2012; 2013].

  6. Amino acid binding by the class I aminoacyl-tRNA synthetases: role for a conserved proline in the signature sequence.

    PubMed Central

    Burbaum, J. J.; Schimmel, P.

    1992-01-01

    Although partial or complete three-dimensional structures are known for three Class I aminoacyl-tRNA synthetases, the amino acid-binding sites in these proteins remain poorly characterized. To explore the methionine binding site of Escherichia coli methionyl-tRNA synthetase, we chose to study a specific, randomly generated methionine auxotroph that contains a mutant methionyl-tRNA synthetase whose defect is manifested in an elevated Km for methionine (Barker, D.G., Ebel, J.-P., Jakes, R.C., & Bruton, C.J., 1982, Eur. J. Biochem. 127, 449-457), and employed the polymerase chain reaction to sequence this mutant synthetase directly. We identified a Pro 14 to Ser replacement (P14S), which accounts for a greater than 300-fold elevation in Km for methionine and has little effect on either the Km for ATP or the kcat of the amino acid activation reaction. This mutation destabilizes the protein in vivo, which may partly account for the observed auxotrophy. The altered proline is found in the "signature sequence" of the Class I synthetases and is conserved. This sequence motif is 1 of 2 found in the 10 Class I aminoacyl-tRNA synthetases and, in the known structures, it is in the nucleotide-binding fold as part of a loop between the end of a beta-strand and the start of an alpha-helix. The phenotype of the mutant and the stability and affinity for methionine of the wild-type and mutant enzymes are influenced by the amino acid that is 25 residues beyond the C-terminus of the signature sequence.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1304356

  7. Revisions to the stratigraphic nomenclature of the Abiquiu Formation, Abiquiu and contiguous areas, north-central New Mexico

    USGS Publications Warehouse

    Maldonado, Florian; Kelley, Shari A.

    2009-01-01

    Stratigraphic studies and geologic mapping on the Abiquiu 7.5-min quadrangle have led to revision of the stratigraphic nomenclature for the Oligocene to Miocene Abiquiu Formation in north-central New Mexico. The Abiquiu Formation had previously been defined to include informal upper, middle (Pedernal chert member), and lower members. The basement-derived conglomeratic lower member in the northern Jemez Mountains and Abiquiu embayment is here redefined. We propose removing the "lower member" from the Abiquiu Formation because provenance of these coarse sediments is dramatically different than the volcaniclastic strata of the "upper member." Furthermore, we propose that the term "lower member of the Abiquiu Formation" be replaced with an existing unit name, the Ritito Conglomerate of Barker (1958), and that the name Abiquiu Formation be restricted to the volcaniclastic succession. The lower part of the Ritito Conglomerate in Arroyo del Cobre on the Abiquiu quadrangle is 47 m (155 ft) thick and is composed of arkosic conglomeratic beds interbedded with arkosic sands and siltstones. Clasts include, in descending order of abundance, Proterozoic quartzite, granite, metavolcanic rocks, quartz, schist, and gneiss and a trace of Mesozoic sandstone and Paleozoic chert. Clasts are predominantly of pebble and cobble size but range from granule to boulder size. Paleocurrent data collected in the Arroyo del Cobre area indicate that the Ritito Conglomerate was deposited by a south-flowing river system during the Oligocene, eroding Laramide highlands such as the Tusas Mountains to the northeast, which contain predominantly Proterozoic rocks. This depositional setting has also been suggested by previous workers. The middle member or Pedernal chert member is present both at the top of the Ritito Conglomerate and as lenses within the lower part of the Abiquiu Formation. This post-depositional diagenetic chert remains an informal unit called the Pedernal chert.

  8. Are Private Reserves Effective for Jaguar Conservation?

    PubMed

    Gutiérrez-González, Carmina E; Gómez-Ramírez, Miguel A; López-González, Carlos A; Doherty, Paul F

    2015-01-01

    We present the first study of density and apparent survival for a jaguar (Panthera onca) population in northern Mexico using 13 years of camera trap data from 2000 to 2012. We used the Barker robust design model which combines data from closed sampling periods and resight data between these periods to estimate apparent survival and abundance. We identified 467 jaguar pictures that corresponded to 48 jaguar individuals. We included camera type and field technician as covariates for detection probabilities. We used three covariates to evaluate the effect of reserve on jaguar apparent survival: i) private reserve creation ii) later reserve expansions, and iii) cattle ranches' conservation activities. We found that the use of digital cameras in addition to film cameras increased detection probability by a factor of 6x compared with the use of only film cameras (p = 0.34 ± 0.05 and p = 0.05 ± 0.02 respectively) in the closed period and more than three times in the open period (R = 0.91 ± 0.08 and R = 0.30 ± 0.13 mixed and film cameras respectively). Our availability estimates showed no temporary emigration and a fidelity probability of 1. Despite an increase of apparent survival probability from 0.47 ± 0.15 to 0.56 ± 0.11 after 2007, no single covariate explained the change in these point estimates. Mean jaguar density was 1.87 ± 0.47 jaguars/100 km2. We found that 13 years of jaguar population monitoring with our sampling size were not enough for detecting changes in survival or density. Our results provide a baseline for studies evaluating the effectiveness of protected areas and the inclusion of ranch owners in jaguar conservation programs and long-term population viability. PMID:26398115

  9. Ethnopharmacological survey of wild medicinal plants in Showbak, Jordan.

    PubMed

    Al-Qura'n, S

    2009-05-01

    Two main research questions are framing this investigation: (1) the main taxa of the medicinal importance value altered the Showbak forest stand and species composition? (2) The most safe species and what are the toxic ones (unsafe). These two research questions are the vital ones to draw a clear image about the wild medicinal plants of this investigated area of Showbak region in Jordan. 79 wild medicinal plant species were investigated in this study which are used in traditional medication for the treatment of various diseases. Most of the locals interviewed dealt with well-known safe medicinal plants such as Aaronsohnia factorovskyi Warb. et Eig., Achillea santolina L., Adiantum capillus-veneris L., Artemisia herba-alba L., Ceratonia siliqua L., Clematis recta L., Herniaria hirsuta L., Malva neglecta Wallr., Rosmarinus officinalis L., Ruta chalepensis L., Salvia triloba L., Sarcopoterium spinosa (L.) Spach., Thymbra capitata (L.) Hof, and Urginea maritima Barker. Many of the wild medicinal plants investigated were toxic and needed to be practiced by practitioners and herbalists rather than the local healers. These plants include Calotropis procera Willd R.Br., Citrullus colocynthis (L.) Sch., Datura stramonium L., Digitalis purpurea L., Ecballium elaterium (L.) A.Rich., Euphorbia helioscopia L., Euphorbia tinctoria Boiss., Glaucium corniculatum (L.) Curt., Hyoscyamus aureus L., Mandragora officinarum L., Nerium oleander L., Ricinus communis L., Solanum nigrum L., Withania somnifera (L.) Dunel. The conservation of medicinal plants and natural resources is becoming increasingly important, so this research is trying to collect information from local population concerning the use of medicinal plants in Showbak; identify the most important specie; determine the relative importance value of the species and calculate the informant consensus factor (ICF) for the medicinal plants. Obtaining results is relied on the interviewee's personal information and the medicinal use

  10. High Resolution Spectroscopy at the 2.7-m H J Smith and 9.2-m Hobby-Eberly Telescopes, 1969-2000

    NASA Astrophysics Data System (ADS)

    Tull, R. G.

    2000-05-01

    The twentieth century has seen the greatest advances in science and technology in the history of the world. These advances spawned a golden age in astronomy and in the astronomical instrumentation that fueled it. This paper will summarize 31 years of development of high-resolution spectroscopic instrumentation at McDonald Observatory, from the construction of the 2.7-m Harlan J. Smith Telescope and its coudé spectrograph through the completion of the 9.2-m Hobby-Eberly Telescope with its high-resolution fiber-fed spectrograph. We begin with photographic spectroscopy and advance through rapid-scanning photon counting spectrometry under computer control, addition of echelle gratings, Reticon and self-scanned Digicon solid-state imaging detectors, and innovative cross-dispersed echelle spectrometers with large-format CCDs. Funding for all these projects by the National Science Foundation and the National Aeronautics and Space Administration is gratefully acknowledged, as are additional support from University of Texas matching grants and from the Texas state legislature. Thanks also to the many colleagues who have shared this adventure with me: Ed Nather, who taught me computer interfacing techniques; Johnnie Floyd, Don Wells, Steve Vogt, Phil Kelton, Richard Stover, Brenda Young, Phillip MacQueen, David Doss, John Good, Harland Epps, and Mark Cornell, who were involved in various phases of instrument development; and Hans Dekker, who shared ideas developed at ESO. The users developed the observing and data reduction techniques; among these are David Lambert, Chris Sneden, Ed Barker, Larry Trafton, Joc Tomkin, and many others. Tom Barnes and Frank Bash provided moral and logistical support, and Joyce Sampson spent many hours in fund-raising efforts. Finally, I wish to dedicate this work to the memory of Harlan J. Smith who gave unswerving encouragement and support over a period of many years.

  11. [Maternal nutrition during pregnancy conditions the fetal pancreas development, hormonal status and diabetes mellitus and metabolic syndrome biomarkers at birth].

    PubMed

    Sánchez-Muniz, F J; Gesteiro, E; Espárrago Rodilla, M; Rodríguez Bernal, B; Bastida, S

    2013-01-01

    Pregnancy is a vital period where several hyperplasic, hypertrophic processes together with metabolic adaptation and preparation for extra-uterine life take place. Present review accounts for central aspects of nutrition throughout gestation on the embryonic and fetal periods. It is centered in the major changes occurring in fetal pancreas, with special mention to the susceptibility of this main glucose homeostasis organ to support nutritional changes during maturation and development. Studies performed in animal models as human are commented considering the role of maternal nutrition on β-cell mass size, insulin and other pancreatic hormones production, and insulin sensitivity. Details of both the thrifty genotype and phenotype hypothesis are given, indicating that hypo/subnutrition causes metabolic adaptations that permit the future body to grow and develop itself in limited environmental and energetic conditions. The Barker hypothesis is considered suggesting that this metabolic hypothesis is a double-edged sword in the actual abundance World. Lastly the review, taking into account our own research and other papers, analyses less known aspects that relate maternal diet with insulin resistance/sensitivity markers at delivery. Particularly the role of the saturated fatty acid/carbohydrate and omega-6/omega-3 ratios in the frame of maternal diet is reviewed considering the quality of those diets under the Healthy Eating Index and the Adherence to Mediterranean Diet scores and the relationship with insulin resistance profile at birth. Present review ends indicating that nutritional habits should be strongly stated before gestation in order to assure a proper nutrition since the first moment of pregnancy. This will support an adequate fetal and pancreatic growth and development, and in turn, adequate glucose homeostasis during pregnancy and later in life, slowing down or preventing from degenerative diseases related with metabolic syndrome and type 2 diabetes

  12. [The need of prenatal public health initiatives in Poland].

    PubMed

    Jarosz, Mirosław J

    2012-11-01

    The author emphasizes the achievements of the Polish Gynecological Society in the field of improving the health indicators concerning perinatal mortality among infants during the last two decades in Poland. Attention is paid to the contribution of the members of the Society to organizational change in Polish health care after 1990, which resulted in the improvement of the care of mother and child. It is also underlined that the members of the Society contributed to the creation of early detection system of breast and cervical cancer in Poland. However it is noteworthy that in 'Polish Gynecology' - the publication of the Polish Gynecological Society - the number of reports devoted to risky health behaviors of women during periconceptional period and pregnancy is scarce. The author draws attention to the percentage of women who smoke cigarettes and consume alcohol before and during pregnancy Emphasis is also placed on the problem of nutritional disorders (mainly pathological methods of dieting) among Polish women during the reproductive period and in the first weeks of pregnancy (before the pregnancy is confirmed). These aspects may result in epigenetic changes shaping the phenotype of the offspring. The author refers to the Barker's theory of Developmental Origins of Adult Diseases and warns that the above-mentioned health behaviors of women may bring about negative effects for the offspring and future generations, namely susceptibility to chronic diseases: arterial hypertension, obesity type 2 diabetes and metabolic syndrome. Negative effects for the health of offspring may also result from low level of physical activity of women before and during pregnancy The author concludes that it is necessary to intensify the efforts of the Polish Gynecological Society in the area of prenatal public health.

  13. Are Private Reserves Effective for Jaguar Conservation?

    PubMed

    Gutiérrez-González, Carmina E; Gómez-Ramírez, Miguel A; López-González, Carlos A; Doherty, Paul F

    2015-01-01

    We present the first study of density and apparent survival for a jaguar (Panthera onca) population in northern Mexico using 13 years of camera trap data from 2000 to 2012. We used the Barker robust design model which combines data from closed sampling periods and resight data between these periods to estimate apparent survival and abundance. We identified 467 jaguar pictures that corresponded to 48 jaguar individuals. We included camera type and field technician as covariates for detection probabilities. We used three covariates to evaluate the effect of reserve on jaguar apparent survival: i) private reserve creation ii) later reserve expansions, and iii) cattle ranches' conservation activities. We found that the use of digital cameras in addition to film cameras increased detection probability by a factor of 6x compared with the use of only film cameras (p = 0.34 ± 0.05 and p = 0.05 ± 0.02 respectively) in the closed period and more than three times in the open period (R = 0.91 ± 0.08 and R = 0.30 ± 0.13 mixed and film cameras respectively). Our availability estimates showed no temporary emigration and a fidelity probability of 1. Despite an increase of apparent survival probability from 0.47 ± 0.15 to 0.56 ± 0.11 after 2007, no single covariate explained the change in these point estimates. Mean jaguar density was 1.87 ± 0.47 jaguars/100 km2. We found that 13 years of jaguar population monitoring with our sampling size were not enough for detecting changes in survival or density. Our results provide a baseline for studies evaluating the effectiveness of protected areas and the inclusion of ranch owners in jaguar conservation programs and long-term population viability.

  14. Semiclassical approach to model quantum fluids using the statistical associating fluid theory for systems with potentials of variable range.

    PubMed

    Trejos, Víctor M; Gil-Villegas, Alejandro

    2012-05-14

    Thermodynamic properties of quantum fluids are described using an extended version of the statistical associating fluid theory for potentials of variable range (SAFT-VR) that takes into account quantum corrections to the Helmholtz free energy A, based on the Wentzel-Kramers-Brillouin approximation. We present the theoretical background of this approach (SAFT-VRQ), considering two different cases depending on the continuous or discontinuous nature of the particles pair interaction. For the case of continuous potentials, we demonstrate that the standard Wigner-Kirkwood theory for quantum fluids can be derived from the de Broglie-Bohm formalism for quantum mechanics that can be incorporated within the Barker and Henderson perturbation theory for liquids in a straightforward way. When the particles interact via a discontinuous pair potential, the SAFT-VR method can be combined with the perturbation theory developed by Singh and Sinha [J. Chem. Phys. 67, 3645 (1977); and ibid. 68, 562 (1978)]. We present an analytical expression for the first-order quantum perturbation term for a square-well potential, and the theory is applied to model thermodynamic properties of hydrogen, deuterium, neon, and helium-4. Vapor-liquid equilibrium, liquid and vapor densities, isochoric and isobaric heat capacities, Joule-Thomson coefficients and inversion curves are predicted accurately with respect to experimental data. We find that quantum corrections are important for the global behavior of properties of these fluids and not only for the low-temperature regime. Predictions obtained for hydrogen compare very favorably with respect to cubic equations of state.

  15. Retrospective studies.

    PubMed

    Silveira, Patrícia Pelufo; Manfro, Gisele Gus

    2015-01-01

    Large retrospective, epidemiological studies accumulated in the late 1980s, providing increasing evidence to the deeply rooted thought that perinatal events could persistently affect the individual's functioning and health/disease patterns throughout the lifetime. Evidences of such associations can be found in the literature since the beginning of the twentieth century, but studies from Barker, Hales, and colleagues serve as an important hallmark. They proposed the "thrifty phenotype" hypothesis, stating that poor nutrition in fetal and early infant life is detrimental to the development and function of the individuals' organism, predisposing them to the later development of adult chronic diseases. At first used to explain the increased risk for type 2 diabetes in low birth weight individuals, the hypothesis was soon adapted to other systems, becoming one of the core assumptions of the Developmental Origins of Adult Health and Disease (DOHaD) model. The central nervous system is also vulnerable to the effects of environmental variation during fetal or neonatal life. Many researchers have explored the effects of perinatal programming on the human neurodevelopment, and some aspects of the brain structure and/or functioning (such as cognitive function, physiological reactivity to stress, and the risk for behavioral disorders or psychopathology) were shown to be modifiable by the exposure to certain adverse events early in life such as neonatal infections, exposure to gestational psychosocial stress, nutrition during gestation, exposure to drugs, or tobacco smoking during pregnancy. Until recently, most studies focused on birth weight as a strong surrogate of the intrauterine environment, investigating the effects of low birth weight (as a marker of suboptimal fetal environment) on a variety of neurodevelopmental outcomes. Despite the fact that literature reviews on this topic are as old as 1940, the more recent retrospective studies are summarized in this chapter.

  16. Economic Implementation and Optimization of Secondary Oil Recovery

    SciTech Connect

    Cary D. Brock

    2006-01-09

    The St Mary West Barker Sand Unit (SMWBSU or Unit) located in Lafayette County, Arkansas was unitized for secondary recovery operations in 2002 followed by installation of a pilot injection system in the fall of 2003. A second downdip water injection well was added to the pilot project in 2005 and 450,000 barrels of saltwater has been injected into the reservoir sand to date. Daily injection rates have been improved over initial volumes by hydraulic fracture stimulation of the reservoir sand in the injection wells. Modifications to the injection facilities are currently being designed to increase water injection rates for the pilot flood. A fracture treatment on one of the production wells resulted in a seven-fold increase of oil production. Recent water production and increased oil production in a producer closest to the pilot project indicates possible response to the water injection. The reservoir and wellbore injection performance data obtained during the pilot project will be important to the secondary recovery optimization study for which the DOE grant was awarded. The reservoir characterization portion of the modeling and simulation study is in progress by Strand Energy project staff under the guidance of University of Houston Department of Geosciences professor Dr. Janok Bhattacharya and University of Texas at Austin Department of Petroleum and Geosystems Engineering professor Dr. Larry W. Lake. A geologic and petrophysical model of the reservoir is being constructed from geophysical data acquired from core, well log and production performance histories. Possible use of an outcrop analog to aid in three dimensional, geostatistical distribution of the flow unit model developed from the wellbore data will be investigated. The reservoir model will be used for full-field history matching and subsequent fluid flow simulation based on various injection schemes including patterned water flooding, addition of alkaline surfactant-polymer (ASP) to the injected water

  17. SABER: A computational method for identifying active sites for new reactions

    PubMed Central

    Nosrati, Geoffrey R; Houk, K N

    2012-01-01

    A software suite, SABER (Selection of Active/Binding sites for Enzyme Redesign), has been developed for the analysis of atomic geometries in protein structures, using a geometric hashing algorithm (Barker and Thornton, Bioinformatics 2003;19:1644–1649). SABER is used to explore the Protein Data Bank (PDB) to locate proteins with a specific 3D arrangement of catalytic groups to identify active sites that might be redesigned to catalyze new reactions. As a proof-of-principle test, SABER was used to identify enzymes that have the same catalytic group arrangement present in o-succinyl benzoate synthase (OSBS). Among the highest-scoring scaffolds identified by the SABER search for enzymes with the same catalytic group arrangement as OSBS were l-Ala d/l-Glu epimerase (AEE) and muconate lactonizing enzyme II (MLE), both of which have been redesigned to become effective OSBS catalysts, demonstrated by experiments. Next, we used SABER to search for naturally existing active sites in the PDB with catalytic groups similar to those present in the designed Kemp elimination enzyme KE07. From over 2000 geometric matches to the KE07 active site, SABER identified 23 matches that corresponded to residues from known active sites. The best of these matches, with a 0.28 Å catalytic atom RMSD to KE07, was then redesigned to be compatible with the Kemp elimination using RosettaDesign. We also used SABER to search for potential Kemp eliminases using a theozyme predicted to provide a greater rate acceleration than the active site of KE07, and used Rosetta to create a design based on the proteins identified. PMID:22492397

  18. SABER: a computational method for identifying active sites for new reactions.

    PubMed

    Nosrati, Geoffrey R; Houk, K N

    2012-05-01

    A software suite, SABER (Selection of Active/Binding sites for Enzyme Redesign), has been developed for the analysis of atomic geometries in protein structures, using a geometric hashing algorithm (Barker and Thornton, Bioinformatics 2003;19:1644-1649). SABER is used to explore the Protein Data Bank (PDB) to locate proteins with a specific 3D arrangement of catalytic groups to identify active sites that might be redesigned to catalyze new reactions. As a proof-of-principle test, SABER was used to identify enzymes that have the same catalytic group arrangement present in o-succinyl benzoate synthase (OSBS). Among the highest-scoring scaffolds identified by the SABER search for enzymes with the same catalytic group arrangement as OSBS were L-Ala D/L-Glu epimerase (AEE) and muconate lactonizing enzyme II (MLE), both of which have been redesigned to become effective OSBS catalysts, demonstrated by experiments. Next, we used SABER to search for naturally existing active sites in the PDB with catalytic groups similar to those present in the designed Kemp elimination enzyme KE07. From over 2000 geometric matches to the KE07 active site, SABER identified 23 matches that corresponded to residues from known active sites. The best of these matches, with a 0.28 Å catalytic atom RMSD to KE07, was then redesigned to be compatible with the Kemp elimination using RosettaDesign. We also used SABER to search for potential Kemp eliminases using a theozyme predicted to provide a greater rate acceleration than the active site of KE07, and used Rosetta to create a design based on the proteins identified. PMID:22492397

  19. Problem Solving in the Natural Sciences and Early Adolescent Girls' Gender Roles and Self-Esteem a Qualitative and Quantitative Analysis from AN Ecological Perspective

    NASA Astrophysics Data System (ADS)

    Slavkin, Michael

    What impact do gender roles and self-esteem have on early adolescent girls' abilities to solve problems when participating in natural science-related activities? Bronfenbrenner's human ecology model and Barker's behavior setting theory were used to assess how environmental contexts relate to problem solving in scientific contexts. These models also provided improved methodology and increased understanding of these constructs when compared with prior research. Early adolescent girls gender roles and self-esteem were found to relate to differences in problem solving in science-related groups. Specifically, early adolescent girls' gender roles were associated with levels of verbal expression, expression of positive affect, dominance, and supportive behavior during science experiments. Also, levels of early adolescent girls self-esteem were related to verbal expression and dominance in peer groups. Girls with high self-esteem also were more verbally expressive and had higher levels of dominance during science experiments. The dominant model of a masculine-typed and feminine-typed dichotomy of problem solving based on previous literature was not effective in Identifying differences within girls' problem solving. Such differences in the results of these studies may be the result of this study's use of observational measures and analysis of the behavior settings in which group members participated. Group behavior and problem-solving approaches of early adolescent girls seemed most likely to be defined by environmental contexts, not governed solely by the personalities of participants. A discussion for the examination of environmental factors when assessing early adolescent girls' gender roles and self-esteem follows this discussion.

  20. Are Private Reserves Effective for Jaguar Conservation?

    PubMed Central

    Doherty, Paul F.

    2015-01-01

    We present the first study of density and apparent survival for a jaguar (Panthera onca) population in northern Mexico using 13 years of camera trap data from 2000 to 2012. We used the Barker robust design model which combines data from closed sampling periods and resight data between these periods to estimate apparent survival and abundance. We identified 467 jaguar pictures that corresponded to 48 jaguar individuals. We included camera type and field technician as covariates for detection probabilities. We used three covariates to evaluate the effect of reserve on jaguar apparent survival: i) private reserve creation ii) later reserve expansions, and iii) cattle ranches’ conservation activities. We found that the use of digital cameras in addition to film cameras increased detection probability by a factor of 6x compared with the use of only film cameras (p = 0.34 ± 0.05 and p = 0.05 ± 0.02 respectively) in the closed period and more than three times in the open period (R = 0.91 ± 0.08 and R = 0.30 ± 0.13 mixed and film cameras respectively). Our availability estimates showed no temporary emigration and a fidelity probability of 1. Despite an increase of apparent survival probability from 0.47 ± 0.15 to 0.56 ± 0.11 after 2007, no single covariate explained the change in these point estimates. Mean jaguar density was 1.87 ± 0.47 jaguars/100 km2. We found that 13 years of jaguar population monitoring with our sampling size were not enough for detecting changes in survival or density. Our results provide a baseline for studies evaluating the effectiveness of protected areas and the inclusion of ranch owners in jaguar conservation programs and long-term population viability. PMID:26398115

  1. Early origins of adult disease: low birth weight and vascular remodeling.

    PubMed

    Visentin, Silvia; Grumolato, Francesca; Nardelli, Giovanni Battista; Di Camillo, Barbara; Grisan, Enrico; Cosmi, Erich

    2014-12-01

    Cardiovascular diseases (CVD) and diabetes still represent the main cause of mortality and morbidity in the industrialized world. Low birth weight (LBW), caused by intrauterine growth restriction (IUGR), was recently known to be associated with increased rates of CVD and non-insulin dependent diabetes in adult life (Barker's hypothesis). Well-established animal models have shown that environmentally induced IUGR (diet, diabetes, hormone exposure, hypoxia) increases the risk of a variety of diseases later in life with similar phenotypic outcomes in target organs. This suggests that a range of disruptions in fetal and postnatal growth may act through common pathways to regulate the developmental programming and produce a similar adult phenotype. The identification of all involved signaling cascades, underlying the physiopathology of these damages in IUGR fetuses, with their influence on adult health, is still far from satisfactory. The endothelium may be important for long-term remodeling and in the control of elastic properties of the arterial wall. Several clinical and experimental studies showed that IUGR fetuses, neonates, children and adolescents present signs of endothelial dysfunction, valuated by aorta intima media thickness, carotid intima media thickness and stiffness, central pulse wave velocity, brachial artery flow-mediated dilation, laser Doppler skin perfusion and by the measure of arterial blood pressure. In utero identification of high risk fetuses and long-term follow-up are necessary to assess the effects of interventions aimed at preventing pregnancy-induced hypertension, reducing maternal obesity, encouraging a healthy life style and preventing childhood obesity on adult blood pressure and cardiovascular disease in later life.

  2. On occasion of 800th anniversary of birth of Ibn al-Nafis--discoverer of cardiac and pulmonary circulation.

    PubMed

    Masic, Izet

    2010-01-01

    . It stemmed back to the sixteenth century. When Michael Servetus (1511-1553), Anderea Vesalius (?1514-1654), Nicolai Massa (1485-1569), Realdo Colombo (1520-1654), Valverde De Hamusco (1508-1565), Andera Cesalpino (1519-1603), Fabrici d'Aquapendent (1533-1619) and William Harvey (1578-1657) developed the concept. However, Muhyi-d-din At-Tatawi (1896-1945) presented his thesis "Der Lungenkreislauf nach El-Korachi. Dissert, z.eil. d. Doktorwrde, Freiburg im Brisgau 1924" of the blood circulation according to al Qurashi relaying on his discovery of his description of pulmonary circulation in one of ancient manuscripts, He proposed that the real credit for the discovery of the pulmonary circulation belongs this eminent physician of the thirteenth century: Ibn al-Nafis. Later another doctor Abdul Kareem Chihade (1922- ) presented another dissertation in Paris 1951 entitled" decouverte de la circulatio pulmonaire chez Ibn an-Nafis". Published by Institut Francais De Damas 1955. Other prominent professors like: Paul Galiounji and Salman Qatayyah researched extensively in his manuscripts and produced very important monographs. The general consensus is that Ibn al-Nafis' work exerted great influence on the development of medical science, both in the Islamic world and Europe. A closer look on Ibn al-Nafis contribution would indicate that he also described the coronary circulation, the cranial nerves the gall bladder anatomy and many new aspect of ophthalmology. He advocated as well therapy through nutrition. His work integrated the medical knowledge with great clarity and emphasized precision. PMID:21287961

  3. EDITORIAL: Fluctuations and noise in photonics and quantum optics: a special issue in memory of Hermann Haus

    NASA Astrophysics Data System (ADS)

    Abbott, Derek; Shapiro, Jeffrey H.; Yamamoto, Yoshihisa

    2004-08-01

    dedicated this Special Issue to him. The first item is an obituary reflecting on his life and work. The first technical paper in this issue represents Hermann’s last sole author publication; a special thanks is due to A P Flitney for organizing this manuscript into publishable form. We thank the members of the International Programme Committee, listed below, and all those who contributed to making the event such a success. At this point we take the opportunity to express our gratitude to both the authors and reviewers, for their unfailing efforts in preparing and ensuring the high quality of the papers in this Special Issue. International Programme Committee David A Cardimona Air Force Research Laboratory, USA Howard Carmichael University of Auckland, New Zealand Carlton M Caves University of New Mexico, Albuquerque, USA Peter D Drummond University of Queensland, St Lucia, Australia Paul J Edwards University of Canberra, Australia Luca Gammaitoni Università degli Studi di Perugia, Italy Brage Golding Michigan State University, East Lansing, USA Gabriela Gonzalez Louisiana State University, Baton Rouge, USA Guangcan Guo University of Science and Technology of China, Hefei, China Salman Habib Los Alamos National Laboratory, NM, USA Murray Hamilton University of Adelaide, Australia Bei-Lok Hu University of Maryland/College Park, USA Daniel K Johnstone Virginia Commonwealth University, Richmond, USA Franz X Kärtner Massachusetts Institute of Technology, Cambridge, USA Prem Kumar Northwestern University, Evanston, IL, USA Zachary Lemnios DARPA, Arlington, VA, USA Gerd Leuchs Friedrich-Alexander Universität Erlangen--Nürnberg, Germany Hideo Mabuchi California Institute of Technology, Pasadena, USA Peter W Milonni Los Alamos National Laboratory, NM, USA Adrian C Ottewill University College Dublin, Ireland Martin B Plenio Imperial College, London, UK Rajeev J Ram Massachusetts Institute of Technology, Cambridge, USA Farhan Rana Massachusetts Institute of Technology, Cambridge

  4. Free thyroxine, free triiodothyronine and thyroid-stimulating hormone before and after hemodialysis in Saudi patients with end-stage renal disease: is there any difference?

    PubMed

    Alsaran, Khalid; Sabry, Alaa; Alshahhat, Hosamuddin; Babgy, Enas; Alzahrani, Fatemah

    2011-09-01

    Patients on regular hemodialysis (HD) suffer from a chronic illness that is believed not to involve the thyroid gland. However, they may have low levels of serum thyroxine (T4) and tri-iodothyronine (T3). It was found earlier that serum total T3 and free T4 concentrations were significantly higher immediately after a HD session than before. In this single-center prospective study, we evaluated the difference between free T3 (FT3), free T4 (FT4) and thyroid-stimulating hormone (TSH) levels before and immediately after HD sessions in 40 Saudi patients with end-stage renal disease undergoing regular HD at the Prince Salman Center for Kidney Disease, Riyadh, Saudi Arabia. The study involved 23 female and 17 male patients with a mean age of 49.65 ± 16.20 years. None of the study patients had any known thyroid disease. We measured the thyroid hormones monthly for three successive months using the electrochemiluminescence technique both before and after HD sessions. At the end of our study, we found a statistically significant difference between pre-HD and post-HD levels for FT3; in the first month, it was 4.47 ± 1.01 versus 4.86 ± 1.03 pmol/L, (P = 0.004); in the second month, it was 4.48 ± 1.37 versus 4.83 ± 1.64 pmol/L, (P = 0.008); and in the third month, it was 3.84 ± 0.88 versus 4.04 ± 0.84 pmol/L, (P = 0.003). The FT4 in the first month was 15.42 ± 2.75 pmol/L versus 17.20 ± 2.85 pmol/L, P = 0.000, in the second month it was 14.86 ± 2.66 versus 16.74 ± 3.27 pmol/L, P = 0.000 and in the third month it was 14.86 ± 3.93 versus 16.70 ± 4.00 pmol/L, P = 0.000, respectively. However, the pre- and post-HD levels of TSH did not show any statistically significant difference; in the first month it was 3.17 ± 1.47 versus 3.32 ± 1.39 pmol/L, P = 0.254, in the second month it was 2.57 ± 1.36 versus 2.49 ± 1.29 pmol/L, P = 0.299 and in the third month it was 2.36 ± 1.17 versus 2.44 ± 1.22 pmol/L, P = 0.238, respectively. Thus, there was a statistically

  5. Detector response and cosmogenic backgrounds in the exploration of rare event physics

    NASA Astrophysics Data System (ADS)

    Barker, D'Ann

    The next generation of ultra-low background physics experiments will reach energy regions and detector sensitivities beyond those previously used to solve many relevant problems of science. For instance, exploring the nature of dark matter, and answering the question of charge-parity (CP) violation of neutrinos in the lepton sector, require ultra-low background rates in the region of interest of detectors. This thesis studies two aspects related to rare event physics. First, a model of ionization efficiency was developed for low energy nuclear recoils in germanium, a common dark matter target. The fundamental physics processes of stopping power below 100 keV were investigated; it was observed that a component of nuclear stopping power contributes to ionization efficiency. To correctly interpret the experimental threshold, a reliable model for ionization efficiency is necessary. Experimental verification of this model was completed using a neutron source incident on a germanium detector. A Monte Carlo simulation was carried out in parallel by another member of the research group. We used shape analysis to compare the experimental data with the proposed Barker-Mei model and an established model for ionization efficiency, Lindhard et al. with k = 0.159. We found agreement between the experimental data and the Monte Carlo simulations to within 4% for both models. Thus, we conclude that the models are valid for the range of 1 keV to 100 keV. The second component was the evaluation of cosmogenic background events from muons and muon-induced neutrons in liquid argon for a long baseline neutrino oscillation experiment. Analytical models were developed to calculate the background event rates of cosmogenically produced nuclei, particularly 40Cl, with rock overburdens of 0.712 km water equivalent (km.w.e.) and 4.3 km.w.e. The predicted rates were compared to a Monte Carlo simulation of a liquid argon target at similar overburden depths performed by another member of the

  6. Microwave Spectroscopy of the Excited Vibrational States of Methanol

    NASA Astrophysics Data System (ADS)

    Pearson, John; Daly, Adam M.; Bermúdez, Celina

    2015-06-01

    Methanol is the simplest molecule with a three-fold internal rotation and the observation of its νb{8} band served the primary catalyst for the development of internal rotation theory(a,b). The 75 subsequent years of investigation into the νb{8} band region have yielded a large number assignments, numerous high precision energy levels and a great deal of insight into the coupling of νb{t}=3 & 4 with νb{8}, νb{7}, νb{11} and other nearby states(c). In spite of this progress numerous assignment mysteries persist, the origin of almost half the far infrared laser lines remain unknown and all attempts to model the region quantum mechanically have had very limited success. The C3V internal rotation Hamiltonian has successfully modeled the νb{t}=0,1 & 2 states of methanol and other internal rotors(d). However, successful modeling of the coupling between torsional bath states and excited small amplitude motion remains problematic and coupling of multiple interacting excited small amplitude vibrations featuring large amplitude motions remains almost completely unexplored. Before such modeling can be attempted, identifying the remaining low lying levels of νb{7} and νb{11} is necessary. We present an investigation into the microwave spectrum of νb{7}, νb{8} and νb{11} along with the underlying torsional bath states in νb{t}=3 and νb{t}= 4. (a) A. Borden, E.F. Barker J. Chem. Phys., 6, 553 (1938). (b) J. S. Koehler and D. M. Dennison, Phys. Rev. 57, 1006 (1940). (c) R. M. Lees, Li-Hong Xu, J. W. C. Johns, B. P. Winnewisser, and M. Lock, J. Mol. Spectrosc. 243, 168 (2007). (d) L.-H. Xu, J. Fisher, R.M. Lees, H.Y. Shi, J.T. Hougen, J.C. Pearson, B.J. Drouin, G.A. Blake, R. Braakman J. Mol. Spectrosc., 251, 305 (2008).

  7. An Attempt to Observe Debris from the Breakup of a Titan 3C-4 Transtage

    NASA Technical Reports Server (NTRS)

    Barker, E. S.; Matney, M. J.; Yanagisawa, T.; Liou, J.-C.; Abercromby, K. J.; Rodriquez, H. M.; Horstman, M. F.; Seitzer, P.

    2007-01-01

    In February 2007 dedicated observations were made of the orbital space predicted to contain debris from the breakup of the Titan 3C-4 transtage back on February 21, 1992. These observations were carried out on the Michigan Orbital DEbris Survey Telescope (MODEST) in Chile with its 1.3deg field of view. The search region or orbital space (inclination and right ascension of the ascending node (RAAN) was predicted using NASA#s LEGEND (LEO-to-GEO Environment Debris) code to generate a Titan debris cloud. Breakup fragments are created based on the NASA Standard Breakup Model (including fragment size, area-to-mass (A/M), and delta-V distributions). Once fragments are created, they are propagated forward in time with a subroutine GEOPROP. Perturbations included in GEOPROP are those due to solar/lunar gravity, radiation pressure, and major geopotential terms. Barker, et. al, (AMOS Conference Proceedings, 2006, pp. 596-604) used similar LEGEND predictions to correlate survey observations made by MODEST (February 2002) and found several possible night-to-night correlations in the limited survey dataset. One conc lusion of the survey search was to dedicate a MODEST run to observing a GEO region predicted to contain debris fragments and actual Titan debris objects (SSN 25000, 25001 and 30000). Such a dedicated run was undertaken with MODEST between February 17 and 23, 2007 (UT dates). MODEST#s limiting magnitude of 18.0 (S\\N approx.10) corresponds to a size of 22cm assuming a diffuse Lambertian albedo of 0.2. However, based on observed break-up data, we expect most debris fragments to be smaller than 22cm which implies a need to increase the effective sensitivity of MODEST for smaller objects. MODEST#s limiting size can be lowered by increasing the exposure time (20 instead of 5 seconds) and applying special image processing. The special processing combines individual CCD images to detect faint objects that are invisible on a single CCD image. Sub-images are cropped from six

  8. Computer Modeling of Planetary Surface Temperatures in Introductory Astronomy Courses

    NASA Astrophysics Data System (ADS)

    Barker, Timothy; Goodman, J.

    2013-01-01

    Barker, T., and Goodman, J. C., Wheaton College, Norton, MA Computer modeling is an essential part of astronomical research, and so it is important that students be exposed to its powers and limitations in the first (and, perhaps, only) astronomy course they take in college. Building on the ideas of Walter Robinson (“Modeling Dynamic Systems,” Springer, 2002) we have found that STELLA software (ISEE Systems) allows introductory astronomy students to do sophisticated modeling by the end of two classes of instruction, with no previous experience in computer programming or calculus. STELLA’s graphical interface allows students to visualize systems in terms of “flows” in and out of “stocks,” avoiding the need to invoke differential equations. Linking flows and stocks allows feedback systems to be constructed. Students begin by building an easily understood system: a leaky bucket. This is a simple negative feedback system in which the volume in the bucket (a “stock”) depends on a fixed inflow rate and an outflow that increases in proportion to the volume in the bucket. Students explore how changing inflow rate and feedback parameters affect the steady-state volume and equilibration time of the system. This model is completed within a 50-minute class meeting. In the next class, students are given an analogous but more sophisticated problem: modeling a planetary surface temperature (“stock”) that depends on the “flow” of energy from the Sun, the planetary albedo, the outgoing flow of infrared radiation from the planet’s surface, and the infrared return from the atmosphere. Students then compare their STELLA model equilibrium temperatures to observed planetary temperatures, which agree with model ones for worlds without atmospheres, but give underestimates for planets with atmospheres, thus introducing students to the concept of greenhouse warming. We find that if we give the students part of this model at the start of a 50-minute class they are

  9. The Upper Pliocene-Quaternary Evolution of the Ioffe Calcareous Contourite Drift, Western South Atlantic.

    NASA Astrophysics Data System (ADS)

    Ivanova, E. V.; Borisov, D.; Murdmaa, I.; Levchenko, O. V.; Dmitrenko, O.; Emelyanov, E.

    2014-12-01

    -05-00744-a. Barash, M.S., Oskina, N.S., Blyum, N., S., 1983. Quaternary biostratigraphy and surface paleotemperatures based on planktonic foraminifers. In: Barker, PF; Carlson, RL; Johnson, DA; et al. (eds.), Initial Reports of the Deep Sea Drilling Project (U.S. Govt. Printing Office), 72, 849-869, doi:10.2973/dsdp.proc.72.142.1983

  10. Accurate statistical associating fluid theory for chain molecules formed from Mie segments

    NASA Astrophysics Data System (ADS)

    Lafitte, Thomas; Apostolakou, Anastasia; Avendaño, Carlos; Galindo, Amparo; Adjiman, Claire S.; Müller, Erich A.; Jackson, George

    2013-10-01

    A highly accurate equation of state (EOS) for chain molecules formed from spherical segments interacting through Mie potentials (i.e., a generalized Lennard-Jones form with variable repulsive and attractive exponents) is presented. The quality of the theoretical description of the vapour-liquid equilibria (coexistence densities and vapour pressures) and the second-derivative thermophysical properties (heat capacities, isobaric thermal expansivities, and speed of sound) are critically assessed by comparison with molecular simulation and with experimental data of representative real substances. Our new EOS represents a notable improvement with respect to previous versions of the statistical associating fluid theory for variable range interactions (SAFT-VR) of the generic Mie form. The approach makes rigorous use of the Barker and Henderson high-temperature perturbation expansion up to third order in the free energy of the monomer Mie system. The radial distribution function of the reference monomer fluid, which is a prerequisite for the representation of the properties of the fluid of Mie chains within a Wertheim first-order thermodynamic perturbation theory (TPT1), is calculated from a second-order expansion. The resulting SAFT-VR Mie EOS can now be applied to molecular fluids characterized by a broad range of interactions spanning from soft to very repulsive and short-ranged Mie potentials. A good representation of the corresponding molecular-simulation data is achieved for model monomer and chain fluids. When applied to the particular case of the ubiquitous Lennard-Jones potential, our rigorous description of the thermodynamic properties is of equivalent quality to that obtained with the empirical EOSs for LJ monomer (EOS of Johnson et al.) and LJ chain (soft-SAFT) fluids. A key feature of our reformulated SAFT-VR approach is the greatly enhanced accuracy in the near-critical region for chain molecules. This attribute, combined with the accurate modeling of second

  11. Subsurface pCO2, nutrient levels and ventilation in the Norwegian Sea during the past 135 kyr

    NASA Astrophysics Data System (ADS)

    Ezat, M.; Rasmussen, T. L.; Hoenisch, B.; Olsen, J.; Groeneveld, J.; Skinner, L. C.

    2015-12-01

    deglaciation. Paleoceanography. Sortor, R. N., & Lund, D. C. (2011). No evidence for a deglacial intermediate water Δ14C anomaly in the SW Atlantic. Earth and Planetary Science Letters. Thornalley, D. J. R., Barker, S., Broecker, W. S., Elderfield, H., & McCave, I. N. (2011). The Deglacial Evolution of North Atlantic Deep Convection. Science.

  12. New constrains on the thermal history of the Miocene Jarando basin (Southern Serbia)

    NASA Astrophysics Data System (ADS)

    Andrić, Nevena; Životić, Dragana; Fügenschuh, Bernhard; Cvetković, Vladica

    2013-04-01

    The Jarando basin, located in the internal Dinarides, formed in the course of the Miocene extension affecting the whole Alpine-Carpathian-Dinaride system (Schmid et al., 2008). In the study area Miocene extension led to the formation of a core-complex in the Kopaonik area (Schefer et al., 2011) with the Jarando basin located in the hanging wall of the detachment fault. The Jarando basin is characterized by the presence of bituminous coals, whereas in the other intramontane basins in Serbia coalification did not exceed the subbituminous stage within the same stratigraphic level. Furthermore, the basin hosts boron mineralizations (borates and howlite) and a magnesite deposit, which again implies elevated temperatures. This thermal overprint is possibly due to post-magmatic activity related to the emplacement of Oligocene I-type Kopaonik and Miocene S-type Polumir granitoid (Schefer et al., 2011.). This research project is aimed at providing new information about the thermal history of the Jarando basin. Fifteen core samples from three boreholes and 10 samples from the surrounding outcrops were processed for apatite fission-track analysis. Additionally, vitrinite reflectance was measured for 11 core samples of shales from one borehole and 5 samples of coal from an underground mine. VR data of Early to Middle Miocene sediments reveal a strong post-depositional overprint. Values increase with the depth from 0.66-0.79% to 0.83-0.90%. Thus organic matter reached the bituminous stage and experienced temperatures of around 110-120˚C (Barker and Pawlewicz, 1994). FT single grain ages for apatite scatter between 45 Ma to 10 Ma with a general trend towards younger ages with depth. Both, the spread in single grain ages together with the bimodal track lengths distribution clearly point to partial annealing of the detrital apatites. With the temperature given from the VR values the partial annealing points to a rather short-lived thermal event. This is assisted by thermal

  13. Low-velocity zone and topography as a source of site amplification effect on Tarzana hill, California

    USGS Publications Warehouse

    Graizer, V.

    2009-01-01

    Tarzana station is located in the foothills of the Santa Monica Mountains in California near the crest of a low (<20 m) natural hill with gentle slopes. The hill is about 500 m in length by 130 m in width and is formed of extremely weathered shale at the surface to fresh at depth. Average S-wave is about 250 m/s in the top 17-18 m, and S- and P-wave velocities significantly increase below this depth. According to the NEHRP classification based on VS30???300 m/s it is a site class D. Strong-motion instrumentation at Tarzana consisted of an accelerograph at the top of the hill, a downhole instrument at 60 m depth, and an accelerograph at the base of the hill. More than 20 earthquakes were recorded by at least three instruments at Tarzana from 1998 till 2003. Comparisons of recordings and Fourier spectra indicate strong directional resonance in a direction perpendicular to the strike of the hill. The dominant peaks in ground motion amplification on the top of the hill relative to the base are at frequencies ???3.6 and 8-9 Hz for the horizontal components. Our hypothesis is that the hill acts like a wave trap. This results in an amplification at predominant frequencies f=V/4 h (h is layer's thickness) at f???3.6 Hz for S-waves (using average VS17=246 m/s and h=17 m) and f???7.9 Hz for P-waves (using average VP17=535 m/s and h=17 m). As was shown by Bouchon and Barker [Seismic response of a hill: the example of Tarzana, California. Bull Seism Soc Am 1996;86(1A):66-72], topography of this hill amplifies and polarizes ground motion in the frequency range of 3-5 Hz. Hill acts as a magnifying polarizing glass: It polarizes ground motion in the direction perpendicular to the strike of the hill and also amplifies ground motions that had been also amplified by a low-velocity layer.

  14. The case for establishing a Holocaust survivors cohort in Israel

    PubMed Central

    2014-01-01

    In this issue, Keinan-Boker summarises the main studies that have followed up offspring of women exposed to famine during pregnancy and calls for the establishment of a national cohort of Holocaust survivors and their offspring to study inter-generational effects. She suggests that the study would consolidate the fetal origins theory and lead to translational applications to deal with the inter-generational effects of the Holocaust. Barker suggested that alterations in the nutritional supply during critical stages of intra-uterine development permanently alter the structure and metabolism of fetal organs which he termed ‘fetal programming’ (now known as developmental origins of health and disease). The famine studies have played an important role in refining the hypothesis by allowing a ‘quasi-experimental’ setting that would otherwise have been impossible to recreate. The developmental origins hypothesis provides a framework to link genetic, environmental and social factors across the lifecourse and offers a primordial preventive strategy to prevent non-communicable disease. Although the famine studies have provided valuable information, the results from various studies are inconsistent. It is perhaps unsurprising given the problems with collecting and interpreting data from famine studies. Survival bias and information bias are key issues. With mortality rates being high, survivors may differ significantly from non-survivors in factors which influence disease development. Most of the data is at ecological level; a lack of individual-level data and poor records make it difficult to identify those affected and assess the severity of effect. Confounding is also possible due to the varying periods and degrees of food deprivation, physical punishment and mental stress undergone by famine survivors. Nonetheless, there would be value in setting up a cohort of Holocaust survivors and their offspring and Keinan-Boker correctly argues that they deserve special

  15. Virtual Ionosonde Construction by using ITS and IRI-2012 models

    NASA Astrophysics Data System (ADS)

    Kabasakal, Mehmet; Toker, Cenk

    2016-07-01

    actual profiles, which are used for ray tracing between the user defined geographical coordinates. Then, ITS model parameters are obtained from both ray tracing and also the IRI-2012 model. Finally, an ionosonde signal waveform is transmitted through the channel obtained from the ITS model to generate the ionogram. As an application, oblique sounding between two points is simulated with ITS channel model. M-sequence, Barker sequence and complementary sequences are used as sounding waveforms. The effects of channel on the oblique ionogram and sounding waveform characteristics are also investigated.

  16. The Molecular Frame Electric Dipole Moment and Hyperfine Interactions in Hafnium Fluoride, HfF

    NASA Astrophysics Data System (ADS)

    Le, Anh; Steimle, Timothy C.; Skripnikov, Leonid; Titov, Anatoly V.

    2013-06-01

    The identification of HfF^{+} as a possible candidate for a d_{e}} measurement has stimulated new interest in the spectroscopy of both HfF^{+} and neutral HfF. Studies of the neutral are relevant because photoionization schemes can be used to produce the cations. More importantly, computational methodologies used to predict the electronic wavefunction of HfF^{+} can be effectively assessed by making a comparison of predicted and experimental properties of the neutral, which are more readily determinable. The (1,0)[17.9]2.5 -X^{2}Δ_{3/2} band of hafnium monofluoride (HfF) has been recorded using high-resolution laser-induced fluorescence spectroscopy both field-free and in the presence of a static electric field. The field-free spectra of ^{177}HfF, ^{179}HfF, and ^{180}HfF were model to generate a set of fine and hyperfine parameters for the X^{2}Δ_{3/2} (v=0) and [17.9]2.5 (v=1) states. The observed optical Stark shifts for the ^{180}HfF isotopologue were analyzed to produce the molecular frame electric dipole moments of 1.66(1)D and 0.419(7)D for the X^{2}Δ_{3/2} and [17.9]2.5 states, respectively. A two-step ab initio calculation consisting of a two-component generalized relativistic effective core potential calculation (GRECP) followed by a restoration of the proper four-component wavefunction was performed to predict the properties of ground state HfF. B. J. Barker, I. O. Antonov, V. E. Bondybey, and M. C. Heaven, J. Chem. Phys., 134, 201102 (2011). K. C. Cossel, D. N. Gresh, L. C. Sinclair, T. Coffey, L. V. Skripnikov, A. N. Petrov, N. S. Mosyagin, A. V. Titov, R. W. Field, E. R. Meyer, E. A. Cornell and J. Ye, Chem. Phys. Lett., 546, 1 (2012). M. Grau, A. E. Leanhardt, H. Loh, L. C. Sinclair, R. P. Stutz, T. S. Yahn, and E. A. Cornell, J. Mol. Spectroc., 272, 32 (2012). H. Loh, R. P. Stutz, T. S. Yahn, H. Looser, R. W. Field, and E. A. Cornell, J. Mol. Spectroc.,276-277, 49 (2012).

  17. The superior precentral gyrus of the insula does not appear to be functionally specialized for articulation

    PubMed Central

    Fillmore, Paul; Smith, Kimberly; Bonilha, Leonardo; Fridriksson, Julius

    2015-01-01

    Broca (Broca P. Bull Soc Anat Paris 36: 330–357, 1861) influentially argued that posterior left inferior frontal gyrus supports speech articulation. According to an alternative proposal (e.g., Dronkers NF. Nature 384: 159–161, 1996; Wise RJ, Greene J, Buchel C, Scott SK. Lancet 353: 1057–1061, 1999; Baldo JV, Wilkins DP, Ogar J, Willock S, Dronkers NF. Cortex 47: 800–807, 2011), a region in the anterior insula [specifically, the superior precentral gyrus of the insula (SPGI)] is the seat of articulatory abilities. Moreover, Dronkers and colleagues have argued that the SPGI is functionally specialized for (complex) speech articulation. Here, we evaluate this claim using individual-subject functional MRI (fMRI) analyses (e.g., Fedorenko E, Hsieh PJ, Nieto-Castanon A, Whitfield-Gabrieli S, Kanwisher N. J Neurophysiol 104: 1177–1194, 2010). We find that the SPGI responds weakly, if at all, during articulation (parts of Broca's area respond 3–4 times more strongly) and does not show a stronger response to higher articulatory demands. This holds regardless of whether the SPGI is defined functionally (by selecting the most articulation-responsive voxels in the vicinity of the SPGI in each subject individually) or anatomically (by using masks drawn on each individual subject's anatomy). Critically, nonspeech oral movements activate the SPGI more strongly than articulation, especially under the anatomical definition of the SPGI. In line with Hillis et al. (Hillis AE, Work M, Barker PB, Jacobs MA, Breese EL, Maurer K. Brain 127: 1479–1487, 2004; also Trupe L, Varma DD, Gomez Y, Race D, Leigh R, Hillis AE, Gottesman RF. Stroke 44: 740–744, 2013), we argue that previous links between the SPGI, and perhaps anterior insula more generally, and articulation may be due to its high base rate of ischemic damage (and activation in fMRI; Yarkoni T, Poldrack RA, Nichols TE, Van Essen DC, Wager TD. Nat Methods 8: 665–670, 2011), combined with its proximity to regions

  18. Regional Variation in the Timing of Cessation of Laramide Folding, Uplift, and Post Flat-Slab Ignimbrite Flare Ups in West Texas

    NASA Astrophysics Data System (ADS)

    Davidson, M. E.; Casey, J.; Lapen, T. J.

    2013-12-01

    Tertiary volcanism in the Trans-Pecos region of West Texas is thought to be related to: 1) a major Farallon buoyant object-related slab flattening period resulting in early arc volcanic activity progressively shifting eastward to New Mexico and West Texas, 2) a subsequent slab-steepening/roll back or slab break away period resulting in renewed and extensive volcanism and ignimbrite flare ups across the region, and 3) final minor volcanism related to Basin and Range extension. Evidence for these tectonic induced volcanic periods can be observed in volcanic compositional variation and the timing and style of volcanism and deformation. This includes highly varied pre-folding mafic alkaline and calc-alkane volcanic and intrusive rocks from ~46Ma (Eocene) to ~32Ma (Oligocene). This is followed by broadly distributed, post-folding calc-alkaline volcanism with subsidiary alkaline mafic volcanism during subsequent regionally varying slab steepening or break away periods (38Ma to 28Ma). Later, smaller-scale, almost exclusively mafic volcanism is associated with Basin and Range extension that occurred between 25 to 2Ma (Barker, 1987). This study attempts to refine regional differences in the cessation of Laramide folding and episodic slab-asthenosphere influenced volcanism in West Texas by utilizing LA-ICP-MS U/Pb zircon geochronology. Ages have been measured for volcanic rock samples that occur both above and below the angular unconformity, including: the Eagle Mountain Lower Rhyolite, an unnamed tuff and trachyte unit from the Garren Group in the Indio Mountains, the Davis Mountains Huelster Fm. and Petan Basalts, the Chinati Mountains Morita Ranch Fm., the Tascotal Fm. From the Alamito Creek and Green Valley area, the Vieja Group from the Rio Grande River area, and the Big Bend National Park South Rim Fm. and Chisos Fm.. In addition, ages for detrital zircons have been obtained in silicilastics below the unconformity within Tertiary Black Peaks, Hannold Hill, and Canoe

  19. Regional Precipitation Forecast with Atmospheric InfraRed Sounder (AIRS) Profile Assimilation

    NASA Technical Reports Server (NTRS)

    Chou, S.-H.; Zavodsky, B. T.; Jedloved, G. J.

    2010-01-01

    Advanced technology in hyperspectral sensors such as the Atmospheric InfraRed Sounder (AIRS; Aumann et al. 2003) on NASA's polar orbiting Aqua satellite retrieve higher vertical resolution thermodynamic profiles than their predecessors due to increased spectral resolution. Although these capabilities do not replace the robust vertical resolution provided by radiosondes, they can serve as a complement to radiosondes in both space and time. These retrieved soundings can have a significant impact on weather forecasts if properly assimilated into prediction models. Several recent studies have evaluated the performance of specific operational weather forecast models when AIRS data are included in the assimilation process. LeMarshall et al. (2006) concluded that AIRS radiances significantly improved 500 hPa anomaly correlations in medium-range forecasts of the Global Forecast System (GFS) model. McCarty et al. (2009) demonstrated similar forecast improvement in 0-48 hour forecasts in an offline version of the operational North American Mesoscale (NAM) model when AIRS radiances were assimilated at the regional scale. Reale et al. (2008) showed improvements to Northern Hemisphere 500 hPa height anomaly correlations in NASA's Goddard Earth Observing System Model, Version 5 (GEOS-5) global system with the inclusion of partly cloudy AIRS temperature profiles. Singh et al. (2008) assimilated AIRS temperature and moisture profiles into a regional modeling system for a study of a heavy rainfall event during the summer monsoon season in Mumbai, India. This paper describes an approach to assimilate AIRS temperature and moisture profiles into a regional configuration of the Advanced Research Weather Research and Forecasting (WRF-ARW) model using its three-dimensional variational (3DVAR) assimilation system (WRF-Var; Barker et al. 2004). Section 2 describes the AIRS instrument and how the quality indicators are used to intelligently select the highest-quality data for assimilation

  20. No evidence for a deglacial intermediate water Δ14C anomaly in the SW Atlantic

    NASA Astrophysics Data System (ADS)

    Sortor, R. N.; Lund, D. C.

    2011-12-01

    The last deglaciation was characterized by an increase in atmospheric pCO2 and decrease in atmospheric radiocarbon activity. One hypothesis is that these changes were due to out-gassing of 14C-depleted carbon from the abyssal ocean (Broecker and Barker, 2007). Reconstructions of foraminiferal Δ14C from the eastern tropical Pacific (Marchitto et al., 2007; Stott et al. 2009), Arabian Sea (Bryan et al., 2010), and high latitude North Atlantic (Thornalley et al., 2011) show that severe depletions in 14C occurred at intermediate water depths during the last deglaciation. It has been suggested that 14C-depleted water from the abyss upwelled in the Southern Ocean and was then carried by Antarctic Intermediate Water (AAIW) to these sites (Marchitto et al., 2007). On the South Icelandic Rise, Thornalley et al. (2011) find deglacial Δ14C values up to 600% lower than the atmosphere. Since North Atlantic deep waters are not believed to be old enough to cause such an anomaly (Robinson et al. 2005), one possible source is AAIW (Thornalley et al., 2011). Here we evaluate whether or not a large deglacial 14C anomaly occurred at intermediate depths in the Southwest Atlantic. We find that the deglacial Δ14C trend at our site is similar to the atmospheric Δ14C trend. Our results are also largely consistent with data from U/Th-dated corals at shallower water depths on the Brazil Margin (Mangini et al., 2010). We find no evidence in the southwestern Atlantic of large deglacial Δ14C anomalies like those observed in the high latitude North Atlantic (Thornalley et al., 2011). When our results are paired with those from the South Pacific (De Pol-Holz et al., 2010; Rose et al., 2010), it appears AAIW did not carry a highly 14C- depleted signal during the deglaciation. Another source of carbon is apparently required to explain the intermediate-depth Δ14C anomalies in the North Atlantic, Indian, and Pacific Oceans.

  1. Directed networks' different link formation mechanisms causing degree distribution distinction

    NASA Astrophysics Data System (ADS)

    Behfar, Stefan Kambiz; Turkina, Ekaterina; Cohendet, Patrick; Burger-Helmchen, Thierry

    2016-11-01

    Within undirected networks, scientists have shown much interest in presenting power-law features. For instance, Barabási and Albert (1999) claimed that a common property of many large networks is that vertex connectivity follows scale-free power-law distribution, and in another study Barabási et al. (2002) showed power law evolution in the social network of scientific collaboration. At the same time, Jiang et al. (2011) discussed deviation from power-law distribution; others indicated that size effect (Bagrow et al., 2008), information filtering mechanism (Mossa et al., 2002), and birth and death process (Shi et al., 2005) could account for this deviation. Within directed networks, many authors have considered that outlinks follow a similar mechanism of creation as inlinks' (Faloutsos et al., 1999; Krapivsky et al., 2001; Tanimoto, 2009) with link creation rate being the linear function of node degree, resulting in a power-law shape for both indegree and outdegree distribution. Some other authors have made an assumption that directed networks, such as scientific collaboration or citation, behave as undirected, resulting in a power-law degree distribution accordingly (Barabási et al., 2002). At the same time, we claim (1) Outlinks feature different degree distributions than inlinks; where different link formation mechanisms cause the distribution distinctions, (2) in/outdegree distribution distinction holds for different levels of system decomposition; therefore this distribution distinction is a property of directed networks. First, we emphasize in/outlink formation mechanisms as causal factors for distinction between indegree and outdegree distributions (where this distinction has already been noticed in Barker et al. (2010) and Baxter et al. (2006)) within a sample network of OSS projects as well as Java software corpus as a network. Second, we analyze whether this distribution distinction holds for different levels of system decomposition: open

  2. Super- and subcritical turbidity currents and their deposits - a synthesis

    NASA Astrophysics Data System (ADS)

    Postma, George; Cartigny, Matthieu

    2014-05-01

    Popular facies schemes of turbidite deposits presently in use are based on an idealized sequence of turbidite units, such as those erected by Bouma (1962) and Lowe (1982). We discuss here that such approach is flawed, because these idealized sequences do not reveal the spectrum of bedforms produced by supercritical turbidity currents (TCs) that are now found to be common on slopes steeper than 0.6 degrees, i.e. on slopes of deepwater deltas, in canyons, and in confinement of supra-lobe channels. This paper shows and discusses how 'problematic' thick successions comprising structureless and crudely stratified deposits (top-cut out Bouma sequences) in conjunction with scours filled with backset stratification and Bouma Ta are specifically related to bedforms formed by high density super critical flows. It will also be shown that thick tabular and straight beds with Bouma Tb3-1, Tc, Tde, which are possibly linked with debrites (hybrid flows) and often traceable over long km distances (see Haugthon et al. 2009 and Tjalling et al. 2012) can be related to high-density subcritical flows. The ability to infer large-scale dynamics of turbidity currents from deposits allows rough estimates of slope on a basinal scale, and allows better differentiation and prediction of facies in sub-environments such as channel - lobe transitions, where supercritical confined flow transforms into subcritical flows. It will also aid modellers to better relate turbidite deposits with flow dynamics. The linking of turbidite units to large-scale flow dynamics resolves process-facies links that were hitherto unresolved in the Bouma sequence. References: Bouma, A.H. (1962) Sedimentology of Some Flysch Deposits: a Graphic Approach to Facies Interpretation. Elsevier, Amsterdam. 168 pp. Haughton, P.D.W., Davis, C., McCaffrey, W. and Barker, S.P. (2009) Hybrid sediment gravity flow deposits - classification, origin and significance. In: Hybrid and Transitional Submarine Flows (Eds. L.A. Amy, W.B. Mc

  3. Movement patterns and study area boundaries: Influences on survival estimation in capture-mark-recapture studies

    USGS Publications Warehouse

    Horton, G.E.; Letcher, B.H.

    2008-01-01

    The inability to account for the availability of individuals in the study area during capture-mark-recapture (CMR) studies and the resultant confounding of parameter estimates can make correct interpretation of CMR model parameter estimates difficult. Although important advances based on the Cormack-Jolly-Seber (CJS) model have resulted in estimators of true survival that work by unconfounding either death or recapture probability from availability for capture in the study area, these methods rely on the researcher's ability to select a method that is correctly matched to emigration patterns in the population. If incorrect assumptions regarding site fidelity (non-movement) are made, it may be difficult or impossible as well as costly to change the study design once the incorrect assumption is discovered. Subtleties in characteristics of movement (e.g. life history-dependent emigration, nomads vs territory holders) can lead to mixtures in the probability of being available for capture among members of the same population. The result of these mixtures may be only a partial unconfounding of emigration from other CMR model parameters. Biologically-based differences in individual movement can combine with constraints on study design to further complicate the problem. Because of the intricacies of movement and its interaction with other parameters in CMR models, quantification of and solutions to these problems are needed. Based on our work with stream-dwelling populations of Atlantic salmon Salmo salar, we used a simulation approach to evaluate existing CMR models under various mixtures of movement probabilities. The Barker joint data model provided unbiased estimates of true survival under all conditions tested. The CJS and robust design models provided similarly unbiased estimates of true survival but only when emigration information could be incorporated directly into individual encounter histories. For the robust design model, Markovian emigration (future

  4. Transmission of obesity-adiposity and related disorders from the mother to the baby.

    PubMed

    Yajnik, Chittaranjan S

    2014-01-01

    The conventional aetiological model of obesity and diabetes proposes a genetic predisposition and a precipitation by an unhealthy adult lifestyle. This hypothesis was challenged by David Barker who proposed that the intrauterine environment influences the risk of non-communicable diseases (NCDs). The original idea was based on fetal undernutrition because lower birth weight was associated with a higher risk of diabetes and heart disease. However, soon it was clear that the association was U shaped, and that the increased risk in large babies was driven by maternal obesity and diabetes. A number of human and animal studies have refined our ideas of 'fetal programming', which is now thought to be related to acquired chemical changes in DNA (methylation), histones (acetylation and other) and the role of non-coding miRNAs. Maternal nutritional disturbances are the major programming stimulus, in addition to a deranged metabolism, infections, maternal stress, extreme atmospheric temperature, etc. The first demonstration of a link between fetal 'starvation' and future ill-health was in the Dutch Hunger Winter studies. In the prospective Pune Maternal Nutrition Study, we found that small and thin Indian babies were more adipose compared to larger English babies, and their higher risk of future diabetes was reflected in higher insulin and leptin and lower adiponectin concentrations in the cord blood. This phenotype was partly related to a deranged 1-carbon metabolism due to an imbalance in vitamin B12 (low) and folate (high) nutrition, which was also related to insulin resistance in the offspring. Maternal obesity and diabetes have made an increasing contribution to childhood obesity and diabetes at a young age. This was prominently shown in Pima Indians but is now obvious in all other populations. The best window of opportunity to prevent fetal programming of NCDs is in the periconceptional period. This is the period when gametogenesis, fertilisation, implantation

  5. No Association between Low Birth Weight and Cardiovascular Risk Factors in Early Adulthood: Evidence from São Paulo, Brazil

    PubMed Central

    Gomes, Filumena Maria; Subramanian, S. V.; Escobar, Ana Maria de Ulhôa; Valente, Maria Helena; Grisi, Sandra Josefina Ferraz Ellero; Brentani, Alexandra; Fink, Günther

    2013-01-01

    Background A growing literature suggests that low birth weight increases the risk of poor health outcomes in adulthood. We tested this hypothesis among young adults living in São Paulo State, Brazil. Methods and Findings To identify the effects of low birth weight on young adulthood outcomes, a medical assessment of 297 individuals born between 1977 and 1989 was conducted at a primary care unit in São Paulo State, Brazil. We analyzed body mass index (BMI), waist-hip ratio, blood pressure, fasting glucose and total cholesterol levels using linear and logistic regressions. Low birth was negatively associated with BMI (β = −2.0, 95% CI: −3.69, −0.27, p = 0.02), fasting glucose levels (β = −1.9, 95% CI: −3.9, −0.07, p = 0.05), waist-hip ratio (β = −0.03, 95% CI: −0.07, −0.01, p = 0.10), systolic blood pressure (β = −3.32, 95% CI: −7.60, 0.96, p = 0.12), and total cholesterol levels (β = −3.19, 95% CI: −16.43, 10.05, p = 0.636). Low birth weight was also associated with lower odds of young adults being overweight and obese, but neither association was statistically significant. Weight gain in the first 12 months of life was associated with higher adult BMI (β = 0.79, 95% CI: −0.0455, 1.623, p = 0.064) and blood pressure (β = 2.79, 95% CI: 0.22, 5.35, p = 0.034). No associations were found between low birth weight and early life (catch-up) growth. Conclusions Low birth weight was not associated with poor health outcomes among young adults in Brazil. These results appear inconsistent with the original Barker hypothesis, but will need to be corroborated in larger samples with longer follow-ups to allow a more general evaluation of the validity of the hypothesis in low and middle income countries. PMID:23799115

  6. Transmission of obesity-adiposity and related disorders from the mother to the baby.

    PubMed

    Yajnik, Chittaranjan S

    2014-01-01

    The conventional aetiological model of obesity and diabetes proposes a genetic predisposition and a precipitation by an unhealthy adult lifestyle. This hypothesis was challenged by David Barker who proposed that the intrauterine environment influences the risk of non-communicable diseases (NCDs). The original idea was based on fetal undernutrition because lower birth weight was associated with a higher risk of diabetes and heart disease. However, soon it was clear that the association was U shaped, and that the increased risk in large babies was driven by maternal obesity and diabetes. A number of human and animal studies have refined our ideas of 'fetal programming', which is now thought to be related to acquired chemical changes in DNA (methylation), histones (acetylation and other) and the role of non-coding miRNAs. Maternal nutritional disturbances are the major programming stimulus, in addition to a deranged metabolism, infections, maternal stress, extreme atmospheric temperature, etc. The first demonstration of a link between fetal 'starvation' and future ill-health was in the Dutch Hunger Winter studies. In the prospective Pune Maternal Nutrition Study, we found that small and thin Indian babies were more adipose compared to larger English babies, and their higher risk of future diabetes was reflected in higher insulin and leptin and lower adiponectin concentrations in the cord blood. This phenotype was partly related to a deranged 1-carbon metabolism due to an imbalance in vitamin B12 (low) and folate (high) nutrition, which was also related to insulin resistance in the offspring. Maternal obesity and diabetes have made an increasing contribution to childhood obesity and diabetes at a young age. This was prominently shown in Pima Indians but is now obvious in all other populations. The best window of opportunity to prevent fetal programming of NCDs is in the periconceptional period. This is the period when gametogenesis, fertilisation, implantation

  7. Three-dimensional geologic framework modeling of faulted hydrostratigraphic units within the Edwards Aquifer, Northern Bexar County, Texas

    USGS Publications Warehouse

    Pantea, Michael P.; Cole, James C.

    2004-01-01

    northeast of San Antonio (Barker and others, 1994), as well as base flow for agricultural applications farther downstream. Average annual discharge from large springs (Comal, San Marcos, Hueco, and others) from the Edwards aquifer was about 365,000 acre-ft from 1934 to1998, with sizeable fluctuations related to annual variations in rainfall. Withdrawals through pumping have increased steadily from about 250,000 acre-ft during the 1960s to over 400,000 acre-ft in the 1990s in response to population growth, especially in the San Antonio metropolitan area (Slattery and Brown, 1999). Average annual recharge to the system (determined through stream gaging) has also varied considerably with annual rainfall fluctuations, but has been about 635,000 acre-ft over the last several decades.

  8. Electric Power Research Institute: Environmental Control Technology Center.

    SciTech Connect

    1997-06-01

    Operations and maintenance continued this month at the Electric Power Research Institute`s (EPRI`s) Environmental Control Technology Center (ECTC). Testing for the month involved the completion of the Clear Liquor Scrubbing with Anhydrite Production test block extension. Also, the test plan for July (Dry Sorbent Injection with the Carbon Injection System) was developed and reconfiguration activities were initiated. The 1.0 MW Cold-Side Selective Catalytic Reduction (SCR) unit and the 0.4 MW Mini-Pilot Wet Scrubber remained idle this month in a cold-standby mode and were inspected regularly. These units remain available for testing as future project work is identified. In June 1997, the extension to the Anhydrite Production test block was completed. The extended Anhydrite test block was funded by the Electric Power Research Institute (EPRI) after reviewing the promising results from the original test program. Both EPRI and the Department of Energy (DOE) funded the original PRDA test program as part of the DOE`s Advanced Power Systems Program, whose mission is to accelerate the commercialization of affordable, high-efficiency, low-emission, coal-fueled electric generating technologies. The project is designed to develop an advanced FGD process that produces a usable byproduct, anhydrite (anhydrous calcium sulfate). While the pilot portion of the Anhydrite PRDA project was conducted on the 4-MW wet FGD pilot unit at EPRI`s Environmental Control Technology Center (ECTC) in Barker, New York, the extension testing mainly used the 0.4 MW wet FGD pilot unit to reduce operating costs. As discussed in previous progress reports, the original CLS/Anhydrite process included three steps: chloride removal, clear liquor scrubbing, and anhydrite production. The final step in the process involved sending the calcium sulfite slurry from the sludge bed reactor to the anhydrite reaction tank for conversion to anhydrous calcium sulfate (anhydrite). The original objective in the PRDA

  9. Accurate statistical associating fluid theory for chain molecules formed from Mie segments.

    PubMed

    Lafitte, Thomas; Apostolakou, Anastasia; Avendaño, Carlos; Galindo, Amparo; Adjiman, Claire S; Müller, Erich A; Jackson, George

    2013-10-21

    A highly accurate equation of state (EOS) for chain molecules formed from spherical segments interacting through Mie potentials (i.e., a generalized Lennard-Jones form with variable repulsive and attractive exponents) is presented. The quality of the theoretical description of the vapour-liquid equilibria (coexistence densities and vapour pressures) and the second-derivative thermophysical properties (heat capacities, isobaric thermal expansivities, and speed of sound) are critically assessed by comparison with molecular simulation and with experimental data of representative real substances. Our new EOS represents a notable improvement with respect to previous versions of the statistical associating fluid theory for variable range interactions (SAFT-VR) of the generic Mie form. The approach makes rigorous use of the Barker and Henderson high-temperature perturbation expansion up to third order in the free energy of the monomer Mie system. The radial distribution function of the reference monomer fluid, which is a prerequisite for the representation of the properties of the fluid of Mie chains within a Wertheim first-order thermodynamic perturbation theory (TPT1), is calculated from a second-order expansion. The resulting SAFT-VR Mie EOS can now be applied to molecular fluids characterized by a broad range of interactions spanning from soft to very repulsive and short-ranged Mie potentials. A good representation of the corresponding molecular-simulation data is achieved for model monomer and chain fluids. When applied to the particular case of the ubiquitous Lennard-Jones potential, our rigorous description of the thermodynamic properties is of equivalent quality to that obtained with the empirical EOSs for LJ monomer (EOS of Johnson et al.) and LJ chain (soft-SAFT) fluids. A key feature of our reformulated SAFT-VR approach is the greatly enhanced accuracy in the near-critical region for chain molecules. This attribute, combined with the accurate modeling of second

  10. Electric Power Research Institute: environmental Control Technology Center.

    SciTech Connect

    1997-09-04

    Operations and maintenance continued this month at the Electric Power Research Institute`s (EPRI`s) Environmental Control Technology Center (ECTC). Testing for the month involved continued investigations into the Clear Liquor Scrubbing Process for the production of Anhydrous Calcium Sulfate (Anhydrite). The 1.0 MW Cold-Side Selective Catalytic Reduction (SCR) unit and the Carbon Injection System (the Pulse-jet Fabric Filter) remained idle this month in a cold-standby mode and were inspected regularly. From May 3-18, the NYSEG Kintigh Station and the ECTC were off-line for a two-week scheduled Station outage. During the ECTC outage, the major systems of the Center were inspected, and several preventive maintenance activities were completed. A listing of the major O&M outage activities completed during this period is presented in the Pilot/Mini-Pilot section of this report. In May 1997, an extension to the Anhydrite Production test block was started following the NYSEG outage. The extension to the Anhydrite Production test block is being funded by the Electric Power Research Institute (EPRI) after promising results from the original test program. Both EPRI and the Department of Energy (DOE) funded the original test program as part of the DOE`s Advanced Power Systems Program, whose mission is to accelerate the commercialization of affordable, high- efficiency, low-emission, coal-fueled electric generating technologies. While the pilot portion of the Anhydrite project was conducted on the 4.0 MW wet FGD pilot unit at EPRI`s Environmental Control Technology Center (ECTC) in Barker, New York, the extension mainly used the 0.4 MW Mini-Pilot wet FGD unit to reduce operating costs. The project is designed to develop an advanced FGD process that produces a useable byproduct, anhydrite (anhydrous calcium sulfate). The original CLS/Anhydrite process included three steps: chloride removal, clear liquor scrubbing, and anhydrite production. The final step in the process involved

  11. The life-cycle of the digenetic trematode, Proctoeces maculatus (Looss, 1901) Odhner, 1911 (Syn. P. rubtenuis [Linton, 1907] Hanson, 1950), and description of Cerceria adranocerca n. sp

    USGS Publications Warehouse

    Stunkard, H.W.; Uzmann, J.R.

    1959-01-01

    ano,nalus, taken at Cerros Island, Mexico. Hanson ( 1950) identified two specimens collected from Calamus sp. at Bermuda by the late F. D. Barker as Distontuni subtenue Linton, 1907, a species described originally from Calantus calanius in the same area. Comparison of these specimens with those from Tortugas identified by Manter as P. erythraeus established their identity, and P. erythraeus was suppressed as a synonym of Proctoeces subtenue (Linton, 1907). Hanson corrected the statement of Manter (1947), noting that it is the vitellaria, not the uterus, which never extends into the post testicular region.

  12. Pb-isotopic Features of Primitive Rocks from Hess Deep: Distinguishing between EPR and Cocos-Nazca Mantle Source(s)

    NASA Astrophysics Data System (ADS)

    Jean, M. M.; Falloon, T.; Gillis, K. M.

    2014-12-01

    We have acquired high-precision Pb-isotopic signatures of primitive lithologies (basalts/gabbros) recovered from IODP Expedition 345.The Hess Deep Rift, located in the vicinity of the Galapagos triple junction (Cocos, Nazca, and Pacific), is viewed as one the best-studied tectonic windows into fast-spreading crust because a relatively young (<1.5 Ma) cross section of oceanic crust. This allows for (1) characterization of the mantle source(s) at Hess Deep, (2) insight into the extent of isotopic homogeneity or heterogeneity in the area, and (3) constrain the relative contributions from the intruding Cocos-Nazca spreading center. The observed Pb-isotopic variation at Hess Deep covers almost the entire range of EPR MORB (10°N to -5°S). Hess Deep samples range from 208Pb (37.3-38.25), 207Pb (15.47-15.58), 206Pb (17.69-18.91). These compositions suggest that this part of Hess Deep mantle is no more isotopically homogeneous than EPR mantle. Two distinct arrays are also observed: 208Pb-enriched (r2=0.985; n=30) and 208Pb-depleted (r2=0.988; n=6). The 208Pb/204Pb isotopes indicates that the Pb-source for some of the samples at Hess Deep had very low Th/U ratios, whereas other areas around the Galapagos microplate seem to have more "normal" ratios. These trends are less apparent when viewed with 207Pb-isotopes. Instead, the majority of basalts and gabbros follow the NHRL, however, at the depleted-end of this array a negative excursion to more enriched compositions is observed. This negative but linear trend could signify an alteration trend or mixing with an EMI-type mantle source, yet this mixing is not observed with 208Pb. This trend is also observed at Pito Deep, which has similar origins to Hess Deep (Barker et al., 2008; Pollack et al., 2009). The Galapagos region has been considered a testing ground for mixing of HIMU, Enriched Mantle, and Depleted Mantle reservoirs (e.g., Schilling et al., 2002). According to our data, however, an EPR-component must also be

  13. The case for establishing a Holocaust survivors cohort in Israel.

    PubMed

    Fall, Caroline Hd; Kumaran, Kalyanaraman

    2014-01-01

    In this issue, Keinan-Boker summarises the main studies that have followed up offspring of women exposed to famine during pregnancy and calls for the establishment of a national cohort of Holocaust survivors and their offspring to study inter-generational effects. She suggests that the study would consolidate the fetal origins theory and lead to translational applications to deal with the inter-generational effects of the Holocaust. Barker suggested that alterations in the nutritional supply during critical stages of intra-uterine development permanently alter the structure and metabolism of fetal organs which he termed 'fetal programming' (now known as developmental origins of health and disease). The famine studies have played an important role in refining the hypothesis by allowing a 'quasi-experimental' setting that would otherwise have been impossible to recreate. The developmental origins hypothesis provides a framework to link genetic, environmental and social factors across the lifecourse and offers a primordial preventive strategy to prevent non-communicable disease. Although the famine studies have provided valuable information, the results from various studies are inconsistent. It is perhaps unsurprising given the problems with collecting and interpreting data from famine studies. Survival bias and information bias are key issues. With mortality rates being high, survivors may differ significantly from non-survivors in factors which influence disease development. Most of the data is at ecological level; a lack of individual-level data and poor records make it difficult to identify those affected and assess the severity of effect. Confounding is also possible due to the varying periods and degrees of food deprivation, physical punishment and mental stress undergone by famine survivors. Nonetheless, there would be value in setting up a cohort of Holocaust survivors and their offspring and Keinan-Boker correctly argues that they deserve special attention

  14. Solar Wind Fluctuations and Their Consequences on the Magnetosphere

    NASA Technical Reports Server (NTRS)

    Li, Xin-Lin

    2005-01-01

    Efforts have been made to extract the physical meaning of each term in our prediction model of the Dst index using the solar wind as the only input. The work has been published Journal of Geophysical Research (Temerin and Li, 21002). We found different terms in the model representing different current in the magnetospheric system and each current has different rise and decay times, with the symmetric ring current the slowest, then the partial ring current, then the tail current. We also have been trying to understand the physical meaning of the diffusion coefficient used in our prediction model of relativistic electron fluxes at geostationary orbit. The model reproduced the observations of MeV electron flux variations well, the diffusion coefficient had be assumed only die to local magnetic field fluctuations, leading to its 10th power dependence on the L. We have studied the theoretical derivation of the diffusion coefficient and we believe that the effect electric field fluctuations at smaller L could become more significant. We have expanded our previous radiation belt electron prediction model, which predicted MeV electron geosynchronous orbit based on solar wind measurements, to predict MeV electrons inside geosynchronous orbit. The model results are compared with measurements from Polar/CEPPAD. Prediction efficiencies of 0.56 and 0.54, respectively, at L=6 and L=4, have been achieved over the entire year of 1998. This work wa reported at 2003 Fall AGU and has been accepted for publication in Space Weather (Barker et al., 2005). We also have used simultaneous measurements of the upstream solar wind and of energetic electrons at geosynchronous orbit to analyze the response of electrons over a very wide energy range, 50 keV-6MeV, to solar wind variations. Enhancements of energetic electron fluxes over this whole energy range are modulated by the solar wind speed and the polarity of the interplanetary magnetic field (IMF). The solar wind speed seems to be a

  15. Mantle Sources, Mantle Melting and the Genesis of the Central East Greenland Plateau Lavas

    NASA Astrophysics Data System (ADS)

    Brown, E. L.; Barfod, G. H.; Lesher, C. E.

    2006-12-01

    The Central East Greenland (CEG) plateau lavas (56-54 Ma) contain a very complete geochemical record of the opening of the North Atlantic basin in response to the breakup of Pangaea. This record provides an unique opportunity for identifying the mantle source compositions and melting processes involved in the genesis of the North Atlantic Igneous Province (NAIP). The plateau lavas consist of three compositional suites: the volumetrically dominant high-Ti suite (TiO2 ca. 1.67 - 4 wt. %) (HTS) and the minor low-Ti (TiO2 < 1.96 wt. %) and very high-Ti (TiO2 ca. 4 - 6 wt. %) suites (LTS and VHTS, respectively). We present detailed Hf-Nd-Sr data and trace element data for VHTS and LTS lavas closely associated within the lava succession. These uncontaminated lava suites represent the extreme compositional ranges of the plateau lavas and show limited variability in ɛHf (9.58 - 10.96 [VHTS] and 14.39 - 14.68 [LTS]) and a somewhat broader variation in ɛNd (5.42 - 6.73 [VHTS] and 8.29 - 9.68 [LTS]). The LTS and VHTS source compositions bracket the chemical range observed for the HTS lavas. Drawing from the model of [1], we propose that the mantle sources for the VHTS and LTS were intimately associated within the mantle melting regime beneath CEG and were present throughout the generation of the plateau lavas. Correlations between trace element and isotopic data can be accounted for by a forward melting model involving a heterogeneous source containing fusible eclogite and refractory peridotite. These findings are in contrast to the model of [2] proposing that temporal sampling of three distinct and isolated mantle domains within a zoned plume is the dominant control on plateau lava chemistry. Our study highlights the importance of combining isotope and trace element data in understanding melt production in the NAIP and elsewhere. (1) Tegner et al., 1998, Nature, v 395, p 591-594; (2) Barker et al., 2006, Geology, v 34, p 481-484

  16. Tuberous sclerosis complex, mTOR, and the kidney: report of an NIDDK-sponsored workshop.

    PubMed

    Henske, Elizabeth P; Rasooly, Rebekah; Siroky, Brian; Bissler, John

    2014-02-01

    Remarkable basic and translational advances have elucidated the role of the mammalian target of rapamycin (mTOR) signaling network in the pathogenesis of renal disease. Many of these advances originated from studies of the genetic disease tuberous sclerosis complex (TSC), leading to one of the clearest therapeutic opportunities to target mTOR with rapamycin and its analogs ("rapalogs"), which effectively inhibit mTOR complex 1 (mTORC1) by an allosteric mechanism. Clinical trials based on these discoveries have provided strongly positive therapeutic results in TSC (Bissler JJ, McCormack FX, Young LR, Elwing JM, Chuck G, Leonard JM, Schmithorst VJ, Laor T, Brody AS, Bean J, Salisbury S, Franz DN. N Engl J Med 358: 140-151, 2008; Krueger DA, Care MM, Holland K, Agricola K, Tudor C, Mangeshkar P, Wilson KA, Byars A, Sahmoud T, Franz DN. N Engl J Med 363: 1801-1811, 2010; McCormack FX, Inoue Y, Moss J, Singer LG, Strange C, Nakata K, Barker AF, Chapman JT, Brantly ML, Stocks JM, Brown KK, Lynch JP 3rd, Goldberg HJ, Young LR, Kinder BW, Downey GP, Sullivan EJ, Colby TV, McKay RT, Cohen MM, Korbee L, Taveira-DaSilva AM, Lee HS, Krischer JP, Trapnell BC. N Engl J Med 364: 1595-1606, 2011). In June 2013, the National Institute of Diabetes and Digestive and Kidney Diseases convened a small panel of physicians and scientists working in the field to identify key unknowns and define possible "next steps" in advancing understanding of TSC- and mTOR-dependent renal phenotypes. TSC-associated renal disease, which affects >85% of TSC patients, and was a major topic of discussion, focused on angiomyolipomas and epithelial cysts. The third major topic was the role of mTOR and mTOR inhibition in the pathogenesis and therapy of chronic renal disease. Renal cell carcinoma, while recognized as a manifestation of TSC that occurs in a small fraction of patients, was not the primary focus of this workshop and thus was omitted from panel discussions and from this report.

  17. Parameterization of the Extinction Coefficient in Ice and Mixed-Phase Arctic Clouds during the ISDAC Field Campaign

    SciTech Connect

    Korolev, A; Shashkov, A; Barker, H

    2012-03-06

    This report documents the history of attempts to directly measure cloud extinction, the current measurement device known as the Cloud Extinction Probe (CEP), specific problems with direct measurement of extinction coefficient, and the attempts made here to address these problems. Extinction coefficient is one of the fundamental microphysical parameters characterizing bulk properties of clouds. Knowledge of extinction coefficient is of crucial importance for radiative transfer calculations in weather prediction and climate models given that Earth's radiation budget (ERB) is modulated much by clouds. In order for a large-scale model to properly account for ERB and perturbations to it, it must ultimately be able to simulate cloud extinction coefficient well. In turn this requires adequate and simultaneous simulation of profiles of cloud water content and particle habit and size. Similarly, remote inference of cloud properties requires assumptions to be made about cloud phase and associated single-scattering properties, of which extinction coefficient is crucial. Hence, extinction coefficient plays an important role in both application and validation of methods for remote inference of cloud properties from data obtained from both satellite and surface sensors (e.g., Barker et al. 2008). While estimation of extinction coefficient within large-scale models is relatively straightforward for pure water droplets, thanks to Mie theory, mixed-phase and ice clouds still present problems. This is because of the myriad forms and sizes that crystals can achieve, each having their own unique extinction properties. For the foreseeable future, large-scale models will have to be content with diagnostic parametrization of crystal size and type. However, before they are able to provide satisfactory values needed for calculation of radiative transfer, they require the intermediate step of assigning single-scattering properties to particles. The most basic of these is extinction

  18. Prediction of blue, red and green aurorae at Mars

    NASA Astrophysics Data System (ADS)

    Lilensten, J.; Bernard, D.; Barthélémy, M.; Gronoff, G.; Simon Wedlund, C.; Opitz, A.

    2015-09-01

    The upper atmosphere of Mars is a laboratory for better understanding the planetary atmosphere evolution, and is an example of the interaction of the solar wind with an unmagnetized planet that has only patches of crustal magnetic field. In that context, several space missions were launched to study the Martian environment and its aurorae, notably ESA's Mars Express discovered the first aurora-like structures, and more recently NASA's MAVEN, which is dedicated to understand the atmospheric escape. However, none of the existing missions have spectrometers in the visible spectral range for the observation of the upper atmosphere and the aurorae, but there are UV spectrometer which can be used to infer visible aurora emission. The UV aurorae on Mars have a counterpart in the visible spectral range which should be detectable under the right conditions. We discuss what are the most favorable conditions to observe these aurorae discernible with the naked eye. In this paper, we simulate the Martian aurora in the visible spectral range both with an experimental setup (the Planeterrella, which we use to measure intensity with respect to the naked eye) and with a numerical ionosphere simulation model (Trans*/Aeroplanets). We show that the electron impact on CO2 produces strong emissions at 412 nm and 434 nm, i.e., in the blue part of the visible spectrum which are due to the CO2+(A) Fox-Duffendack-Barker bands. The modeling of the electron transport at Mars shows that these blue emissions as well as the emissions of the 630 nm (red) and 557.7 nm (green) lines of atomic oxygen may be observable several times during a solar cycle during strong solar events. The absence of visible spectrometers dedicated to these observations onboard existing space missions and the location of the different Martian rovers, far from the vertically aligned crustal magnetic field lines of Mars, have prevented so far the observations of such an aurora. In the foreseeable future, two missions may

  19. An unusual early Holocene diatom event north of the Getz Ice Shelf (Amundsen Sea): Implications for West Antarctic Ice Sheet development

    NASA Astrophysics Data System (ADS)

    Esper, O.; Gersonde, R.; Hillenbrand, C.; Kuhn, G.; Smith, J.

    2011-12-01

    , which point to specific scenarios involving e.g. changes in the food web that can be related to warmer surface water temperatures. Such warming of shelf waters may be related with an overshooting Atlantic Meridional Overturning Circulation (AMOC) and strong injection of warmer North Atlantic Deep Water into the Southern Ocean water masses at Termination I as reported by [2]. Such finding may highlight the effects of AMOC changes on Antarctic ice shelf extent and coastal ecosystems. [1] Hillenbrand et al., 2010. J. Quat. Sci. 25 (3), 280-295. [2] Barker et al., 2010. Nature Geosci. 3, 567-571.

  20. Fractal analysis reveals pernicious stress levels related to boat presence and type in the Indo-Pacific bottlenose dolphin, Tursiops aduncus

    NASA Astrophysics Data System (ADS)

    Seuront, Laurent; Cribb, Nardi

    2011-06-01

    The stress induced in the Indo-Pacific bottlenose dolphin, Tursiops aduncus, by boat presence and type was investigated in a highly urbanized coastal environment, the Port Adelaide River-Barker Inlet Estuary, South Australia. The level of stress experienced by bottlenose dolphins was inferred from the distribution patterns of their dive durations. Dive duration has previously been shown to increase under boat traffic conditions, and is considered as a typical avoidance behavior. Dive durations were opportunistically recorded from land-based stations between January 2008 and October 2010 in the absence of boat traffic, and in the presence of kayaks, inflatable motor boats, powerboats and fishing boats. Subsequent analyses were based on nearly 6000 behavioral observations. No significant differences in dive durations were found between control observations (i.e. absence of boats) and boat interferences, which could erroneously lead to conclude that boat traffic did not induce any stress in T. aduncus. In contrast, the scaling exponents of the cumulative probability distribution of dive durations obtained in the absence of boat traffic and under different conditions of boat interferences show (i) that the presence of boats affected the complexity of dive duration patterns and (ii) that stress levels were a function of boat type. Specifically, the complexity of dive duration patterns (estimated by the scaling exponent ϕ) did not significantly differ between control behavioral observations and behavioral observations conducted in the presence of kayaks. A significant increased in behavioral stress (i.e. decreasing values of ϕ) was, however, induced by the presence of fishing boats, motorized inflatable boats and powerboats. This demonstrates that traditional approaches based on the analysis of averaged behavioral metrics may not be sensitive enough to detect changes in the distribution pattern of behavioral sequences, hence underestimate the potential consequences of

  1. PREFACE: Progress in Nonequilibrium Green's Functions IV

    NASA Astrophysics Data System (ADS)

    Bonitz, Michael; Balzer, Karsten

    2010-04-01

    This is the fourth volume1 of articles on the theory of Nonequilibrium Green's functions (NEGF) and their modern application in various fields such as plasma physics, semiconductor physics, molecular electronics and high energy physics. It contains 23 articles written by experts in many-body theory and quantum transport who summarize recent progress in their respective area of research. The articles are based on talks given at the interdisciplinary conference Progress in Nonequilibrium Green's functions IV which was held 17-21 August 2009 at the University of Glasgow, Scotland. This conference continues the tradition of the previous meetings which started in 1999 and which aimed at an informal exchange across field boundaries. The previous meetings and the earlier proceedings proved to be very stimulating not only for young researchers but also for experienced scientists, and we are convinced that this fourth volume will be as successful as the previous ones. As before, this volume includes only extended review-type papers which are written in a way that they are understandable to a broad interdisciplinary audience. All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administrated by the Editors assuring highest scientific standards. In the review process some papers were substantially revised and improved and some were rejected. This conference would not have been possible without the remarkable work of the local organizing team around John Barker and Scott Roy and the generous financial support from the University of Glasgow and the Deutsche Forschungsgemeinschaft via SFB-Transregio 24. Michael Bonitz and Karsten Balzer Kiel, February 2010 1 The first two volumes are Progress in Nonequilibrium Green's functions, M Bonitz (ed) and Progress in Nonequilibrium Green's functions II, M Bonitz and D Semkat (eds), which were published by World Scientific (Singapore), in 2000 and 2003, respectively (ISBN

  2. Varying results using the shell weights of different planktonic foraminiferal species as a proxy for changing carbonate ion concentrations in the Cariaco Basin, Venezuela

    NASA Astrophysics Data System (ADS)

    Marshall, B. J.; McConnell, M. C.; Thunell, R.; Astor, Y.

    2011-12-01

    Ocean acidification, due in part to increased atmospheric CO2, is thought to reduce calcification rates of planktonic foraminifera. A positive linear relationship has been found between foraminiferal shell weight and the carbonate ion concentrations [CO32-] of the waters in which they calcify (Barker and Elderfield, 2002). Such a relationship provides a useful proxy for determining past changes in ocean carbonate chemistry. The Cariaco Basin, Venezuela (10°30' N, 65°31 W) is an ideal study area to determine the relationship between seawater [CO32-] and planktonic foraminiferal shell weight as the region is characterized by the seasonal upwelling of low pH, low temperature, and low carbonate ion concentrated waters. In this study we use biweekly sediment trap samples and concurrent hydrographic measurements collected between January 2005 and May 2010 in the Cariaco Basin to assess the relationship between [CO32-] and shell weight of three planktonic foraminiferal species, Globigerinoides ruber, Orbulina universa and Globigerinoides sacculifer. Measured salinity, pH, sea surface temperature (SST) and total alkalinity (TA) were used to estimate pCO2 and [CO32-]. Size-normalized shells of G. ruber, O. universa and G. sacculifer were picked (> 10 per sample), photographed for size analysis and weighed. Globigerinoides ruber shell weights varied from 10.4 μg to 17.7 μg, with an average weight of 14.62 μg from 2005 to 2007, with concurrent surface water [CO32-] ranging from ~220-280 μmol/kg. Orbulina universa shell weights ranged from 35.4 μg to 67.8 μg with an average shell weight of 50.1 μg. Preliminary data reveal a strong positive linear relationship between foraminiferal shell weight and [CO32-] for G. ruber (R2 = 0.52, 99% confidence level; p = 0.007) but no significant relationship for O. universa (R2 = 0.05, ; p = 0.4). The initial results suggest that the foraminiferal shell weight changes of certain planktonic foraminiferal species may reflect changes

  3. Bifunctional TaqII restriction endonuclease: redefining the prototype DNA recognition site and establishing the Fidelity Index for partial cleaving

    PubMed Central

    2011-01-01

    Background The TaqII enzyme is a member of the Thermus sp. enzyme family that we propounded previously within Type IIS restriction endonucleases, containing related thermophilic bifunctional endonucleases-methyltransferases from various Thermus sp.: TaqII, Tth111II, TthHB27I, TspGWI, TspDTI and TsoI. These enzymes show significant nucleotide and amino acid sequence similarities, a rare phenomenon among restriction endonucleases, along with similarities in biochemical properties, molecular size, DNA recognition sequences and cleavage sites. They also feature some characteristics of Types I and III. Results Barker et al. reported the Type IIS/IIC restriction endonuclease TaqII as recognizing two distinct cognate site variants (5'-GACCGA-3' and 5'-CACCCA-3') while cleaving 11/9 nucleotides downstream. We used four independent methods, namely, shotgun cloning and sequencing, restriction pattern analysis, digestion of particular custom substrates and GeneScan analysis, to demonstrate that the recombinant enzyme recognizes only 5'-GACCGA-3' sites and cleaves 11/9 nucleotides downstream. We did not observe any 5'-CACCCA-3' cleavage under a variety of conditions and site arrangements tested. We also characterized the enzyme biochemically and established new digestion conditions optimal for practical enzyme applications. Finally, we developed and propose a new version of the Fidelity Index - the Fidelity Index for Partial Cleavage (FI-PC). Conclusions The DNA recognition sequence of the bifunctional prototype TaqII endonuclease-methyltransferase from Thermus aquaticus has been redefined as recognizing only 5'-GACCGA-3' cognate sites. The reaction conditions (pH and salt concentrations) were designed either to minimize (pH = 8.0 and 10 mM ammonium sulphate) or to enhance star activity (pH = 6.0 and no salt). Redefinition of the recognition site and reaction conditions makes this prototype endonuclease a useful tool for DNA manipulation; as yet, this enzyme has no practical

  4. EDITORIAL: Fluctuations and noise in photonics and quantum optics: a special issue in memory of Hermann Haus

    NASA Astrophysics Data System (ADS)

    Abbott, Derek; Shapiro, Jeffrey H.; Yamamoto, Yoshihisa

    2004-08-01

    dedicated this Special Issue to him. The first item is an obituary reflecting on his life and work. The first technical paper in this issue represents Hermann’s last sole author publication; a special thanks is due to A P Flitney for organizing this manuscript into publishable form. We thank the members of the International Programme Committee, listed below, and all those who contributed to making the event such a success. At this point we take the opportunity to express our gratitude to both the authors and reviewers, for their unfailing efforts in preparing and ensuring the high quality of the papers in this Special Issue. International Programme Committee David A Cardimona Air Force Research Laboratory, USA Howard Carmichael University of Auckland, New Zealand Carlton M Caves University of New Mexico, Albuquerque, USA Peter D Drummond University of Queensland, St Lucia, Australia Paul J Edwards University of Canberra, Australia Luca Gammaitoni Università degli Studi di Perugia, Italy Brage Golding Michigan State University, East Lansing, USA Gabriela Gonzalez Louisiana State University, Baton Rouge, USA Guangcan Guo University of Science and Technology of China, Hefei, China Salman Habib Los Alamos National Laboratory, NM, USA Murray Hamilton University of Adelaide, Australia Bei-Lok Hu University of Maryland/College Park, USA Daniel K Johnstone Virginia Commonwealth University, Richmond, USA Franz X Kärtner Massachusetts Institute of Technology, Cambridge, USA Prem Kumar Northwestern University, Evanston, IL, USA Zachary Lemnios DARPA, Arlington, VA, USA Gerd Leuchs Friedrich-Alexander Universität Erlangen--Nürnberg, Germany Hideo Mabuchi California Institute of Technology, Pasadena, USA Peter W Milonni Los Alamos National Laboratory, NM, USA Adrian C Ottewill University College Dublin, Ireland Martin B Plenio Imperial College, London, UK Rajeev J Ram Massachusetts Institute of Technology, Cambridge, USA Farhan Rana Massachusetts Institute of Technology, Cambridge

  5. Flammable Gas Release Estimates for Modified Sluicing Retrieval of Waste from Selected Hanford Single-Shell Tanks

    SciTech Connect

    Huckaby, James L.; Wells, Beric E.

    2004-03-05

    The high-level radioactive wastes in many single-shell tanks (SSTs) at the Hanford Site are to be retrieved by a modified sluicing method that uses water jets to dissolve the water-soluble waste and mobilize the water-insoluble waste. Retrieval operations will liberate any waste gases trapped in the wetted solid waste matrix, and these gases will be released into the tank headspaces. Because the trapped gases include the flammable species hydrogen, methane, and ammonia, a concern exists that a flammable mixture could be formed in the tank headspaces. This report combines conservative retained gas inventory estimates and tank data with anticipated waste retrieval rates to estimate the potential headspace flammability of selected SSTs during modified sluicing waste retrieval operations. Considered here are nine of the 12 tanks from the 241-S tank farm (241-S-107, 241-S-111, and 241-S 112 are not considered) and Tank 241-U-107. This report is intended to support the specification of process controls that ensure flammable conditions do not develop in the tank headspaces. Consequently, the physical scenarios considered, the models developed to estimate retained gas releases and the tank headspace compositions under these scenarios, and the model input data are intended to conservatively assess the potential to reach headspace flammability. The analyses are intended to address worst-case conditions and establish reasonable upper bounds on the achievable flammability of the tank headspaces. Flammable retained gas inventories, for example, are based on the 95th percentile developed by Barker and Hedengren (2003), giving 95% confidence that actual inventories are smaller than those used in the calculations. Gas releases and headspace flammability were evaluated for three general scenarios: a very aggressive dissolution and erosion of saltcake waste by water jets impinging on the waste surface, the drainage of interstitial liquids from saltcake during a shutdown of the

  6. A Glimpse at South Atlantic Deep and Surface Water Evolution over the Last 40 Ky

    NASA Astrophysics Data System (ADS)

    Waelbroeck, C.; Vazquez Riveiros, N.; Arz, H. W.; Gottschalk, J.; Skinner, L. C.; Dokken, T. M.

    2014-12-01

    intermediate water, and circumpolar deep water. We further compare core MD08-3167 records with benthic isotopic and surface records from other well-dated South Atlantic cores of comparable temporal resolution, i.e. western tropical Atlantic core GeoB3910, and Sub-Antarctic cores MD07-3076Q and TNO57-21 (Barker and Diz, 2014).

  7. The star formation history and dust content in the far outer disc of M31

    NASA Astrophysics Data System (ADS)

    Bernard, Edouard J.; Ferguson, Annette M. N.; Barker, Michael K.; Hidalgo, Sebastian L.; Ibata, Rodrigo A.; Irwin, Michael J.; Lewis, Geraint F.; McConnachie, Alan W.; Monelli, Matteo; Chapman, Scott C.

    2012-03-01

    We present a detailed analysis of two fields located 26 kpc (˜5 radial scalelengths) from the centre of M31 along the south-west semimajor axis of the disc. One field samples the major axis populations - the Outer Disc field - while the other is offset by ˜18 arcmin and samples the warp in the stellar disc - the warp field. The colour-magnitude diagrams (CMDs) based on Hubble Space Telescope Advanced Camera for Surveys imaging reach old main-sequence turn-offs (˜12.5 Gyr). We apply the CMD-fitting technique to the warp field to reconstruct the star formation history (SFH). We find that after undergoing roughly constant star formation until about 4.5 Gyr ago, there was a rapid decline in activity and then a ˜1.5 Gyr lull, followed by a strong burst lasting 1.5 Gyr and responsible for 25 per cent of the total stellar mass in this field. This burst appears to be accompanied by a decline in global metallicity which could be a signature of the inflow of metal-poor gas. The onset of the burst (˜3 Gyr ago) corresponds to the last close passage of M31 and M33 as predicted by detailed N-body modelling, and may have been triggered by this event. We reprocess the deep M33 outer disc field data of Barker et al. in order to compare consistently derived SFHs. This reveals a similar duration burst that is exactly coeval with that seen in the M31 warp field, lending further support to the interaction hypothesis. We reliably trace star formation as far back as 12-13 Gyr ago in the outer disc of M31, while the onset of star formation occurred about 2 Gyr later in M33, with median stellar ages of 7.5 and 4.5 Gyr, respectively. The complex SFHs derived, as well as the smoothly varying age-metallicity relations, suggest that the stellar populations observed in the far outer discs of both galaxies have largely formed in situ rather than migrated from smaller galactocentric radii. The strong differential reddening affecting the CMD of the Outer Disc field prevents derivation of the

  8. Pseudotachylyte: Reading the Record of Paleoseismicity in Low-Angle Normal Faults

    NASA Astrophysics Data System (ADS)

    Smith, D. M.; Goodwin, L. B.; Feinberg, J. M.; Ellis, A. P.

    2012-12-01

    allow seismicity. A third, similarly extensive zone of pseudotachylyte veins in Central Otago, New Zealand will be included with our Arizona sites in this analysis. Previous work in this location shows more than 100 veins dipping 10-30°, from 1- 3 cm thick, extending up to 200 m along strike (Barker, 2005). The Otago site emphasizes seismicity as a component of LANF development in different tectonic regions, and will allow comparison of LANF pseudotachylytes of disparate host rock and ages (Miocene in U.S. sites, Cretaceous in NZ). Preliminary data demonstrate a range in magnetic characteristics of the samples we have collected. Veins within felsic granodiorite and alaskite in the South Mountains show susceptibilities ranging from 0.48 -1.06 x 10-3 SI. These values are indistinguishable from host rock susceptibilities (0.48 - 1.32 x 10-3 SI). In contrast, Rincon pseudotachylyte has magnetic susceptibilities ranging from 29.3 to >80.0 x 10-3 SI and porphyroclastic gneiss host rock values are a considerably lower 7.44 - 8.64 x 10-3 SI. We therefore anticipate this test will only be successfully applied toward some of our samples. Our presentation will include both descriptions of pseudotachlylyte zones and networks and preliminary paleomagnetic data.

  9. Quantifying Preferential Flow and Seasonal Storage in an Unsaturated Fracture-Facial Domain

    NASA Astrophysics Data System (ADS)

    Nimmo, J. R.; Malek-Mohammadi, S.

    2012-12-01

    unsaturated zones [Pruess, 1999]. Lewis, M.A., H.K. Jones, D.M.J. Macdonald, M. Price, J.A. Barker, T.R. Shearer, A.J. Wesselink, and D.J. Evans (1993), Groundwater storage in British aquifers--Chalk, National Rivers Authority R&D Note, 169, Bristol, UK. Nimmo, J.R. (2010), Theory for Source-Responsive and Free-Surface Film Modeling of Unsaturated Flow, Vadose Zone Journal, 9(2), 295-306, doi:10.2136/vzj2009.0085. Price, M., R.G. Low, and C. McCann (2000), Mechanisms of water storage and flow in the unsaturated zone of the Chalk aquifer, Journal of Hydrology, 233(1-4), 54-71. Pruess, K. (1999), A mechanistic model for water seepage through thick unsaturated zones in fractured rocks of low matrix permeability, Water Resources Research, 35(4), 1039-1051.

  10. Isotopic analysis of methane by Cavity Ringdown Spectroscopy (CRDS) Application to the deep-sea Congolobe fan

    NASA Astrophysics Data System (ADS)

    Caprais, J.; Cathalot, C.; de Prunelé, A.; Ruffine, L.; Cassarino, L.; Le Bruchec, J.; Olu, K.; Rabouille, C.

    2013-12-01

    sampled from different biological habitats (microbial mats, reduced sediments, and vesicomyides) using the ROV Victor (IFREMER). Distribution of dissolved methane in pore-waters and its isotopic composition (δ13CH4) were measured at these stations using a new versatile tool based on Cavity RingDown Spectroscopy (CRDS) from Picarro The preliminary results indicate active diagenetic and chemo-synthetic processes within the surface sediment of the Congo lobes (e.g. methanogenesis and anaerobic oxidation of methane). The δ13CH4 ratio differs from one site to another and seems to follow a path related to the distribution of the living communities, suggesting that the biogeochemical processes within the sediment directly structure the benthic communities at the seafloor. References: 1 Alperin, M. J. et al. Glob. Biogeochem. Cycle 2, 279-288 (1988). 2 Barker, J. F. & Fritz, P. Nature 293, 289-291 (1981). 3 Schmale, O. et al. Biogeosciences 9, 4969-4977 (2012).

  11. Development of a short-term irradiance prediction system using post-processing tools on WRF-ARW meteorological forecasts in Spain

    NASA Astrophysics Data System (ADS)

    Rincón, A.; Jorba, O.; Baldasano, J. M.

    2010-09-01

    , and NMAE decreases down to 32%. The REC method shows a reduction of 6% of RMSE, 79% of BIAS, and NMAE decreases down to 28%. When comparing stations at different altitudes, the overestimation is enhanced at coastal stations (less than 200m) up to 900 W m-2 h-1. The results allow us to analyze strengths and drawbacks of the irradiance prediction system and its application in the estimation of energy production from photovoltaic system cells. References Boi, P.: A statistical method for forecasting extreme daily temperatures using ECMWF 2-m temperatures and ground station measurements, Meteorol. Appl., 11, 245-251, 2004. Bozic, S.: Digital and Kalman filtering, John Wiley, Hoboken, New Jersey, 2nd edn., 1994. Glahn, H. and Lowry, D.: The use of Model Output Statistics (MOS) in Objective Weather Forecasting, Applied Meteorology, 11, 1203-1211, 1972. Roeger, C., Stull, R., McClung, D., Hacker, J., Deng, X., and Modzelewski, H.: Verification of Mesoscale Numerical Weather Forecasts in Mountainous Terrain for Application to Avalanche Prediction, Weather and forecasting, 18, 1140-1160, 2003. Skamarock, W., Klemp, J., Dudhia, J., Gill, D., Barker, D. M., Wang, W., and Powers, J. G.: A Description of the Advanced Research WRF Version 2, Tech. Rep. NCAR/TN-468+STR, NCAR Technical note, 2005.

  12. High resolution numerical simulation (WRF V3) of an extreme rainy event over the Guadeloupe archipelago: Case of 3-5 january 2011.

    NASA Astrophysics Data System (ADS)

    Bernard, Didier C.; Cécé, Raphaël; Dorville, Jean-François

    2013-04-01

    spatio-temporal distribution of simulated rainfall could help to design the prevention and evacuation plan, particularly for the flooding areas. The meteorological variable fields simulated are evaluated by comparison with observed data of meteorological weather stations (French Met. Office) available in the area. Brévignon, C., 2003: Atlas climatique: l'environnement atmosphérique de la Guadeloupe, de Saint-Barthélémy et Saint-martin. Météo-France, Service Régional de Guadeloupe, 92 pp. Cécé, R., T. Plocoste, C. D'Alexis, D. Bernard and J.-F. Dorville, 2012: Modélisation numérique à l'échelle locale des situations météorologiques observées au cours de la transition saison sèche - saison humide à l'aide de WRF ARW V3 : cas de l'archipel de la Guadeloupe. AMA 2012, Toulouse. Skamarock, W. C., J. B. Klemp, J. Dudhia, D. O. Gill, D. M. Barker, M. G. Duda, X.-Y. Huang, W. Wang, and J. G. Powers, 2008: A Description of the Advanced Research WRF Version 3.Tech. Rep., National Center for Atmospheric Research.

  13. LOW VELOCITY ZONE AND TOPOGRAPHY AS A SOURCE OF SITE AMPLIFICATION EFFECT ON TARZANA HILL, CALIFORNIA

    NASA Astrophysics Data System (ADS)

    Graizer, V.

    2009-12-01

    for S-waves (using average Vs17 = 246 m/sec and h=17 m) and f ~ 7.9 Hz for P-waves (using average Vp17 = 535 m/sec and h=17 m). As was shown by Bouchon and Barker (1996), topography of this hill amplifies and polarizes ground motion in the frequency range of 3-5 Hz. Hill acts as a magnifying polarizing glass: It polarizes ground motion in the direction perpendicular to the strike of the hill and also amplifies ground motions that had been also amplified by a low-velocity layer.

  14. Solar vs. Tidal Forcing of Centennial to Decadal Scale Variability in Marine Sedimentary Records from the Western Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Kirkwood, G.; Domack, E.; Brachfeld, S.

    2004-12-01

    and Whorf, 2000). We discuss these alternative forcing mechanisms with respect to: contrasts in regional processes of glacial marine sedimentation, the mechanism whereby the tidal or solar signal is transferred to the sediment column and possible cryptic stratigraphy of the Palmer Deep record (ie. missing time, Nederbragt and Thurow, 2002). Resolution of the correct forcing factor is critical to our ability to hind cast the last 100 years of paleoenvironmental data within these cores and hence to our attempts at recognizing an anthropogenic climate signal in the Antarctic Peninsula region. Howell, P. (2001), ARAND time series and spectral analysis package for the Macintosh, Brown University, IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series #2001-044, NOAA/NGDC Paleoclimatology Program, Boulder, Colo. Keeling, Charles D., and Timothy P. Whorf (2000), The 1,800-year oceanic tidal cycle: A possible cause of rapid climate change, Proc. Natl. Acad. Sci., 97 (8), 3814-3819. Nederbragt, A. J., and Thurow, J. (2002) Sediment color variation and annual accumulation rates in laminated Holocene sediments, Site 1098, Palmer Deep. In Barker, P. F., Camerlenghi, A., Acton, G. D., and Ramsay, A.T.S. (eds), Proc. ODP Sci. Results, 178: College Station TX (Ocean Drilling Program). Warner, Nathaniel R., and E. Domack (2002), Millennial-to decadal-scale paleoenvironmental change during the Holocene in the Palmer Deep, Antarctica, as recorded by particle size analysis, Paleoceanography, 17 (3), 8004, doi:10.1029/2000PA000602.

  15. A high resolution WRF model for wind energy forecasting

    NASA Astrophysics Data System (ADS)

    Vincent, Claire Louise; Liu, Yubao

    2010-05-01

    diffusion constant caused damping of the unrealistic fluctuations, but did not completely solve the problem. Using two-way nesting also mitigated the unrealistic fluctuations significantly. It can be concluded that for real case LES modelling of wind farm circulations, care should be taken to ensure the consistency between the mesoscale weather forcing and LES models to avoid exciting spurious noise along the forcing boundary. The development of algorithms that adequately model the sub-grid-scale mixing that cannot be resolved by LES models is an important area for further research. References Liu, Y. Y._W. Liu, W. Y.Y. Cheng, W. Wu, T. T. Warner and K. Parks, 2009: Simulating intra-farm wind variations with the WRF-RTFDDA-LES modeling system. 10th WRF Users' Workshop, Boulder, C, USA. June 23 - 26, 2009. Skamarock, W., J. Dudhia, D.O. Gill, D.M. Barker, M.G.Duda, X-Y. Huang, W. Wang and J.G. Powers, A Description of the Advanced Research WRF version 3, NCAR Technical Note TN-475+STR, NCAR, Boulder, Colorado, 2008.

  16. PREFACE: The IARU International Scientific Congress on Climate Change: Global Risks, Challenges and Decisions (10-12 March, Copenhagen, Denmark)

    NASA Astrophysics Data System (ADS)

    2009-01-01

    by the IARU universities In keeping with normal scientific practice, a procedure for producing the synthesis report that has been adopted optimises the chances of arriving at a product that will receive a broad backing from the scientific community as being a message that can be sent to the non-scientific community and that explains current understanding in climate change science The Writing Team will also be responsible for writing the book Members of the Writing Team (in alphabetical order) Professor Joe Alcamo, University of Stellenbosch Dr Terry Barker, Cambridge University Professor Daniel Kammen, University of California - Berkeley Professor Rik Leemans, Environmental Systems Analysis Group, Wageningen University Professor Diana Liverman, Oxford University Professor Mohan Munasinghe, Chairman, Munasinghe Institute for Development (MIND) Dr Balgis Osman-Elasha, Higher Council for Environment and Natural Resources (HCENR), Sudan Professor Katherine Richardson, University of Copenhagen Professor John Schellnhuber, Potsdam Institute for Climate Impact Research and visiting professor at the University of Oxford Professor Will Steffen, Australian National University Professor Lord Nicholas Stern, London School of Economics and Political Science (LSE) Professor Ole Wæver, University of Copenhagen 2 Key Messages from the Congress Key Message 1: Climatic Trends Recent observations confirm that, given high rates of observed emissions, the worst-case IPCC scenario trajectories (or even worse) are being realized For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts Key

  17. Computing and software

    USGS Publications Warehouse

    White, Gary C.; Hines, J.E.

    2004-01-01

    The reality is that the statistical methods used for analysis of data depend upon the availability of software. Analysis of marked animal data is no different than the rest of the statistical field. The methods used for analysis are those that are available in reliable software packages. Thus, the critical importance of having reliable, up–to–date software available to biologists is obvious. Statisticians have continued to develop more robust models, ever expanding the suite of potential analysis methodsavailable. But without software to implement these newer methods, they will languish in the abstract, and not be applied to the problems deserving them.In the Computers and Software Session, two new software packages are described, a comparison of implementation of methods for the estimation of nest survival is provided, and a more speculative paper about how the next generation of software might be structured is presented.Rotella et al. (2004) compare nest survival estimation with different software packages: SAS logistic regression, SAS non–linear mixed models, and Program MARK. Nests are assumed to be visited at various, possibly infrequent, intervals. All of the approaches described compute nest survival with the same likelihood, and require that the age of the nest is known to account for nests that eventually hatch. However, each approach offers advantages and disadvantages, explored by Rotella et al. (2004).Efford et al. (2004) present a new software package called DENSITY. The package computes population abundance and density from trapping arrays and other detection methods with a new and unique approach. DENSITY represents the first major addition to the analysis of trapping arrays in 20 years.Barker & White (2004) discuss how existing software such as Program MARK require that each new model’s likelihood must be programmed specifically for that model. They wishfully think that future software might allow the user to combine pieces of likelihood

  18. An Attempt to Observe Debris from the Breakup of a Titan 3C-4 Transtage

    NASA Astrophysics Data System (ADS)

    Barker, E.; Matney, M.; Yanagisawa, T.; Liou, J.; Abercromby, K.; Rodriguez, H.; Horstman, M.; Seitzer, P.

    In February 2007 dedicated observations were made of the orbital space predicted to contain debris from the breakup of the Titan 3C-4 transtage back on February 21, 1992. These observations were carried out on the Michigan Orbital Debris Survey Telescope (MODEST) in Chile with its 1.3? field of view. The search region or orbital space (inclination and right ascension of the ascending node (RAAN) was predicted using NASA's LEGEND (LEO-to-GEO Environment Debris) code to generate a Titan debris cloud. Breakup fragments are created based on the NASA Standard Breakup Model (including fragment size, area-to-mass (A/M), and delta-V distributions). Once fragments are created, they are propagated forward in time with a subroutine GEOPROP. Perturbations included in GEOPROP are those due to solar/lunar gravity, radiation pressure, and major geopotential terms. Barker, et. al, (Proceedings of AMOS 2006 Technical Conference, pp. 596-604) used similar LEGEND predictions to correlate survey observations made by MODEST in February 2002 and found several possible night-to-night correlations in the limited survey dataset. One conclusion of the February 2002 survey search was to dedicate a MODEST run to observing a GEO region predicted to contain debris fragments and actual Titan debris objects (SSN 25000, 25001 and 30000). Such a dedicated run was undertaken with MODEST between February 17 and 23, 2007 (UT dates). MODEST's limiting magnitude of 18.0 (SN~10) corresponds to a size of 22cm assuming a diffuse Lambertian albedo of 0.2. However, based on observed break-up data, we expect most debris fragments to be smaller than 22cm which implies a need to increase the effective sensitivity of MODEST for smaller objects. MODEST's limiting size could not be lowered by increasing the exposure time from 5 to 20 seconds due to trailing of the image. However, special image processing did allow the detection of smaller debris. Special processing combined several individual CCD images to detect

  19. PREFACE: 4th Workshop on Theory, Modelling and Computational Methods for Semiconductors (TMCSIV)

    NASA Astrophysics Data System (ADS)

    Tomić, Stanko; Probert, Matt; Migliorato, Max; Pal, Joydeep

    2014-06-01

    renowned theoretical groups from many European countries (Spain, France, Ireland, Germany, Switzerland, Luxemburg, Norway, Italy, Poland, Denmark, Sweden, Serbia, etc.), as well as Asia (Iran, Japan) and USA. We would like to thank all participants for making this a very successful meeting and for their contribution to the conference programme and these proceedings. We would also like to acknowledge the financial support from the Institute of Physics (Semiconductor Physics Group and Computational Physics Group), EPSRC-UK, the CECAM UK-Hartree Node, CCP9, and Quantum Wise (distributors of Atomistix). The Editors Acknowledgments Conference Organising Committee: Stanko Tomić (Chair, University of Salford) Matt Probert (University of York) Max Migliorato (University of Manchester) Joydeep Pal (University of Manchester) Programme Committee: David Whittaker (University of Sheffield, UK) John Robertson (University of Cambridge, UK) Risto Nieminen (Helsinki University of Technology Finland) Eoin O'Reilly (Tyndall Institute Cork Republic of Ireland) Marco Califano (University of Leeds, UK) Stewart Clark (University of Durham, UK) Stanko Tomić (University of Salford, UK) Mauro Pereira (Sheffield Hallam University, UK) Aldo Di Carlo (University of Rome ''Tor Vergata,'' Italy) Lev Kantorovich (King's College London, UK) Mervin Roy (University of Leicester, UK) Ben Hourahine (University of Strathclyde, UK) Rita Magri (University of Modena and Reggio Emilia, Italy) Zoran Ikonic (University of Leeds) John Barker (University of Glasgow) The proceedings were edited and compiled by Joydeep Pal, Max Migliorato and Stanko Tomić.

  20. CHAIRMEN'S FOREWORD: The Seventh International Conference on New Phenomena in Mesoscopic Structures & The Fifth International Conference on Surfaces and Interfaces of Mesoscopic Devices

    NASA Astrophysics Data System (ADS)

    Aoyagi, Yoshinobu; Goodnick, Stephen M.

    2006-05-01

    , non-equilibrium transport, instabilities, nano-electro-mechanical systems, mesoscopic Josephson effects, phase coherence and breaking, and the Kondo effect •Systems of nanodevices: Quantum cellular automata, systolic SET processors, quantum neural nets, adaptive effects in circuits, and molecular circuits •Nanomaterials: nanotubes, nanowires, organic and molecular materials, self-assembled nano wires, and organic devices •Nanobioelectronics: electronic properties of biological structures on the nanoscale. This year's conference was organized by Prof Stephen Goodnick, Arizona State University, and Prof Yoshinobu Aoyagi, Tokyo Institute of Technology. The conference benefited from 14 invited speakers, whose topics spanned the above list, and a total of 97 registered attendees. The largest contingent was from Japan, followed closely by the US. In total, there were 49 from Japan, 31 fiom the US, and 17 from Europe. The organizers want to especially thank the sponsors for the meeting: The Office of Naval Research, the Army Research Office, and Arizona State University on the US side, and the Japan Society for the Promotion of Science, through their 151 Committee, on the Japanese side. PROGRAM COMMITTEE •Prof Gerhard Abstreiter, Technical University of Munich •Prof Tsuneya Ando, Tokyo Institute of Technology •Prof John Barker, University of Glasgow •Prof Jonathan Bird, the University at Buffalo •Prof Robert Blick, University of Wisconsin •Prof David Ferry, Chair, Arizona State University •Dr Yoshiro Hirayama, NTT Basic Research Laboratories •Dr Koji Ishibashi, RIKEN •Prof Carlo Jacoboni, University of Modena •Prof David Janes, Purdue University •Prof Friedl Kuchar, University of Leoben •Prof K. Matsumoto, Osaka University •Prof Wolfgang Porod, Notre Dame University •Prof Michiharu Tabe, Shizuoka University •Prof Joachim Wolter, Eindhoven Institute of Technology •Prof Lukas Worschech, University of Würzburg •Dr Naoki Yokoyama, Fujitsu

  1. Calcareous palaeosols and temples in the floodplain of Thebes, Egypt: droughts and decisions

    NASA Astrophysics Data System (ADS)

    Graham, Angus; Hunter, Morag A.; Pennington, Benjamin T.; Strutt, Kristian D.

    2014-05-01

    Lake Manzala (Nile Delta) suggests this period was one of declining discharge (Stanley et al. 2003). Amenhotep III's temple floor lies 2m above the calcareous palaeosol and its construction lies within the broad dating of the ancient surface. It is possible that low discharge levels enabled him to build his temple high and dry of the Nile floods. Future seasons should allow us to clarify this using 14C and OSL dating, and in time we hope to shed more light on the fluvial history of the Nile and how this affected the decision making of the ancient Egyptians. References Graham, A., Strutt, K.D., Emery, V.L., Jones, S., Barker. D.B. 2013. Theban Harbours and Waterscapes Survey, 2013, Journal of Egyptian Archaeology 99, 35-52. Graham, A., Strutt, K.D., Hunter, M.A., Jones, S., Masson, A., Millet, M., Pennington, B.T. 2012. Theban Harbours and Waterscapes Survey, 2012, Journal of Egyptian Archaeology 98, 27-42. Stanley, D.J., Krom, M.D., Cliff, R.A. and Woodward, J.C. 2003. Nile flow failure at the end of the Old Kingdom, Egypt: Strontium isotopic and petrologic evidence, Geoarchaeology 18(3), 395-402.

  2. Late Archean mineralised cyanobacterial mats and their modern analogs

    NASA Astrophysics Data System (ADS)

    Kazmierczak, J.; Altermann, W.; Kremer, B.; Kempe, S.; Eriksson, P. G.

    2008-09-01

    cells have the ability to bind various ions and may serve as nucleation centres for a variety of minerals [5, 6]. These, often amorphous precursor mineral phases can be transformed, during later diagenesis, into authigenic carbonates, feldspar and phyllosilicates, as observed in the case of both Nauga Formation and Lake Van cyanobacterial sheaths and capsules. The early massive appearance of benthic coccoid cyanobacteria, as evidenced by the mineralised mats in the Neoarchean Nauga Formation, and their ability to produce fine-grained limestones, confirms the significant role of these micro organisms in the formation of vast deposits of marine micritic limestones, as suggested also for younger geologic ages [7, 8]. References [1] Altermann, W. and Nelson, D. R. (1998) Sed. Geol. 120, 225-256. [2] Kazmierczak, J. and Altermann, W. (2002) Science 298, 2351. [3] Kempe, S. et al. (1991) Nature 394, 605-608. [4] Kazmierczak, J. and Altermann, W. (2002) 16th Intern. Sed. Congr. Abstract Vol., 191. [5] Douglas, S. and Beveridge, T. J. (1998) FEMS Microbiol. Ecol. 26, 79-88. [6] Barker, W. W. and Banfield, J. F. (1998) Geomicrobiol. J. 15, 223-244. [7] Kazmierczak, J. et al. (1996) Acta Palaeont. Polonica 41, 319-338. [8] Altermann, W. et al. (2006) Geobiology 4, 147- 166.

  3. PREFACE: Workshop Photograph and Program

    NASA Astrophysics Data System (ADS)

    2011-07-01

    : Bonnie Fleming (Yale U.))18:30 Supernovae neutrino detection (20') Ines Gil-Botella (CIEMAT)18:50 Neutrino cross-section in Liquid Argon in the GeV range (15') Flavio Cavanna (U. of L'Aquila)19:05 Analysis of the ArgoNeuT neutrino data (15') Carl Bromberg (Michigan State U.)19:20 Neutrino event reconstruction (15') Gary Barker (U. of Warwick) Tuesday 30 March 2010Ways to improve the Liquid Argon Charge Imaging technology I (Chair: Christos Touramanis (U. of Liverpool))09:00 Liquid Argon LEM TPC (30') Filippo Resnati (ETH Zurich)09:30 Micromegas for charge readout of double phase liquid Argon large TPCs (20') Alain Delbart (Saclay)09:50 Development of Thick-GEMs for GEM-TPC Tracker (20') Fuminori Sakuma (RIKEN)10:10 Optical readout of the ionization (20') Neil Spooner (U. of Sheffield)10:30 Scintillation light readout (20') Kostas Mavrokoridis (U. of Liverpool)10:50-11:10 Coffee break Ways to improve the Liquid Argon Charge Imaging technology II (Chair: Alberto Marchionni (ETH Zurich))11:10 Development of cold electronics (30') Veljko Radeka (BNL)11:40 Development of a frontend ASIC and DAQ system Dario Autiero (IPN Lyon)12:00 CAEN digitizers (20') Carlo Tintori (CAEN)12:20 Recent results from Liquid Argon R&D activity (20') Masashi Tanaka (KEK)12:40 Results from the materials test stand and status of LAPD (20') Brian Rebel (FNAL)13:00 Purging and purification: 6 m3 @CERN (20') Alessandro Curioni (ETH Zurich)13:20-14:30 Lunch break14:30-20:00 Trip to J-PARC to visit T2K Beam Facility and Near Detector20:00-22:00 Workshop dinner at Okura Frontier Hotel Tsukuba Wednesday 31 March 2010Ways to improve the Liquid Argon Charge Imaging technology III (Chair: Takasumi Maruyama (KEK))09:00 ArgonTube and UV laser ionization (25') Biagio Rossi (U. of Bern)09:25 Detector magnetization (15') Andreas Badertscher (ETH Zurich)09:40 HV system (25') Sosuke Horikawa (ETH Zurich) Localization studies (Chair: Takuya Hasegawa (KEK))10:05 Okinoshima site study (20') Masakazu Yoshioka (KEK)10

  4. Land - Ocean Climate Linkages and the Human Evolution - New ICDP and IODP Drilling Initiatives in the East African Rift Valley and SW Indian Ocean

    NASA Astrophysics Data System (ADS)

    Zahn, R.; Feibel, C.; Co-Pis, Icdp/Iodp

    2009-04-01

    enable us to establish the linkages between the ocean climatology of the SW Indian and terrestrial climates of Eastern Africa during key periods of global climate change. Combining the ICDP records of East African terrestrial climate at key hominin sites with IODP records of marine climate variability at the SE African continental margin will help to test if pulses of hominin evolutionary innovation were linked with periods of enhanced variability of local terrestrial environments and marine climatology of the Indian Ocean. * co-PIs of the ICDP initiative HSPDP are A.S. Cohen, R. Arrowsmith, A.K. Behrensmeyer, C. Feibel, R. Johnson, Z. Kubsa, D. Olago, R. Potts, R. Renaut * co-PIs of the IODP initiative SAFARI are R. Zahn, I. Hall, R. Schneider, M. Á. Bárcena, S. Barker, A. Biastoch, Chr. Charles, J. Compton, R. Cowling, P. Diz, L. Dupont, J.-A. Flores, S. Goldstein, S. Hemming, K. Holmgren, J. Lee-Thorp, G. Knorr, C. Lear, A. Mazaud, G. Mortyn, F. Peeters, B. Preu, R. Rickaby, J. Rogers, A. Rosell-Mele, Chr. Reason, V. Spiess, M. Trauth, G. Uenzelmann-Neben, S. Weldeab, P. Ziveri

  5. PREFACE: Workshop Photograph and Program

    NASA Astrophysics Data System (ADS)

    2011-07-01

    : Bonnie Fleming (Yale U.))18:30 Supernovae neutrino detection (20') Ines Gil-Botella (CIEMAT)18:50 Neutrino cross-section in Liquid Argon in the GeV range (15') Flavio Cavanna (U. of L'Aquila)19:05 Analysis of the ArgoNeuT neutrino data (15') Carl Bromberg (Michigan State U.)19:20 Neutrino event reconstruction (15') Gary Barker (U. of Warwick) Tuesday 30 March 2010Ways to improve the Liquid Argon Charge Imaging technology I (Chair: Christos Touramanis (U. of Liverpool))09:00 Liquid Argon LEM TPC (30') Filippo Resnati (ETH Zurich)09:30 Micromegas for charge readout of double phase liquid Argon large TPCs (20') Alain Delbart (Saclay)09:50 Development of Thick-GEMs for GEM-TPC Tracker (20') Fuminori Sakuma (RIKEN)10:10 Optical readout of the ionization (20') Neil Spooner (U. of Sheffield)10:30 Scintillation light readout (20') Kostas Mavrokoridis (U. of Liverpool)10:50-11:10 Coffee break Ways to improve the Liquid Argon Charge Imaging technology II (Chair: Alberto Marchionni (ETH Zurich))11:10 Development of cold electronics (30') Veljko Radeka (BNL)11:40 Development of a frontend ASIC and DAQ system Dario Autiero (IPN Lyon)12:00 CAEN digitizers (20') Carlo Tintori (CAEN)12:20 Recent results from Liquid Argon R&D activity (20') Masashi Tanaka (KEK)12:40 Results from the materials test stand and status of LAPD (20') Brian Rebel (FNAL)13:00 Purging and purification: 6 m3 @CERN (20') Alessandro Curioni (ETH Zurich)13:20-14:30 Lunch break14:30-20:00 Trip to J-PARC to visit T2K Beam Facility and Near Detector20:00-22:00 Workshop dinner at Okura Frontier Hotel Tsukuba Wednesday 31 March 2010Ways to improve the Liquid Argon Charge Imaging technology III (Chair: Takasumi Maruyama (KEK))09:00 ArgonTube and UV laser ionization (25') Biagio Rossi (U. of Bern)09:25 Detector magnetization (15') Andreas Badertscher (ETH Zurich)09:40 HV system (25') Sosuke Horikawa (ETH Zurich) Localization studies (Chair: Takuya Hasegawa (KEK))10:05 Okinoshima site study (20') Masakazu Yoshioka (KEK)10

  6. Observing plants dealing with soil water stress: Daily soil moisture fluctuations derived from polymer tensiometers

    NASA Astrophysics Data System (ADS)

    van der Ploeg, Martine; de Rooij, Gerrit

    2014-05-01

    fluctuations in water content changes, with both root water uptake and root water excretion. The magnitude of the water content change was in the same order for all treatments, thus suggesting compensatory uptake. References Bakker G, Van der Ploeg MJ, de Rooij GH, Hoogendam CW, Gooren HPA, Huiskes C, Koopal LK and Kruidhof H. New polymer tensiometers: Measuring matric pressures down to the wilting point. Vadose Zone J. 6: 196-202, 2007. Blackman PG and Davies WJ. Root to shoot communication in maize plants of the effects of soil drying. J. Exp. Bot. 36: 39-48, 1985. Davies WJ and Zhang J. Root signals and the regulation of growth and development of plants in drying soil. Annu. Rev. Plant Physiol. Plant Mol. Biol. 42: 55-76, 1991. Gollan T, Passioura JB and Munns R. Soil water status affects the stomatal conductance of fully turgid wheat and sunflower leafs. Aust. J. Plant Physiol. 13: 459-464, 1986. Gowing DJG, Davies WJ and Jones HG. A Positive Root-sourced Signal as an Indicator of Soil Drying in Apple, Malus x domestica Borkh. J. Exp. Bot. 41: 1535-1540, 1990. Grace J. Environmental controls of gas exchange in tropical rain forests. In: Press, M.C, J.D. Scholes and M.G. Barker (ed.). Physiological plant ecology: the 39th Symposium of the British Ecological Society. Blackwell Science, United Kingdom, 1999. Kool D, Agam N, Lazarovitch N, Heitman JL, Sauer TJ, Ben-Gal A. A review of approaches for evapotranspiration partitioning. Agricultural and Forest Meteorology 184: 56- 70, 2014. Mansfield TA and De Silva DLR. Sensory systems in the roots of plants and their role in controlling stomatal function in the leaves. Physiol. Chem. Phys. & Med. 26: 89-99, 1994. Sadras VO and Milroy SP. Soil-water thresholds for the responses of leaf expansion and gas exchange: a review. Field Crops Res. 47: 253-266, 1996. Schröder N, Lazarovitch N, Vanderborcht J, Vereecken H, Javaux M. Linking transpiration reduction to rhizosphere salinity using a 3D coupled soil-plant model. Plant Soil 2013

  7. Circum-North Pacific tectonostratigraphic terrane map

    USGS Publications Warehouse

    Nokleberg, Warren J.; Parfenov, Leonid M.; Monger, James W.H.; Baranov, Boris B.; Byalobzhesky, Stanislav G.; Bundtzen, Thomas K.; Feeney, Tracey D.; Fujita, Kazuya; Gordey, Steven P.; Grantz, Arthur; Khanchuk, Alexander I.; Natal'in, Boris A.; Natapov, Lev M.; Norton, Ian O.; Patton, William W.; Plafker, George; Scholl, David W.; Sokolov, Sergei D.; Sosunov, Gleb M.; Stone, David B.; Tabor, Rowland W.; Tsukanov, Nickolai V.; Vallier, Tracy L.; Wakita, Koji

    1994-01-01

    schematic fashion because of more limited data and because the offshore terranes and early Cenozoic and older overlap assemblages generally are obscured by extensive late Cenozoic sedimentary cover that is not shown unless thicker than two kilometers; (2) marginal contacts of offshore Cenozoic and Cretaceous sedimentary basins do not match contacts of onshore Cenozoic and Cretaceous sedimentary units because offshore basins are limited to those regions with sediment thicknesses greater than two kilometers; (3) stratigraphic columns, included at the end of this explanation. are provided only for onshore terranes because the geology of offshore terranes is generally less well-known; and (4) for simplicity, the major onshore Cenozoic sedimentary basins are generally not defined and described separately because the onshore part of the map is designed to emphasize terranes and overlap volcanic assemblages that are crucial for both for tectonic and metallogenic analyses published elsewhere (Nokleberg and others, 1993, 1994a). Several key geologic sources were used in the compilation of the map. For Alaska. the basic outcrop pattern for the map is from Beikman (1980), Gehrels and Berg (1992, 1994). Barker and others ( 1994). Brew (1994), and Moli-Stalcup and others ( 1994b). The distribution of terranes is from Jones and others (1987) and Monger and Berg (1987), with modification by Grantz and other (1991 ). Worall (199 1 ), okleberg and others (1993, 1994a), the cited references, and the Alaskan co-authors of this report. For the Canadian Cordillera. the basic outcrop pattern is from Monger and Berg ( 1987), Wheeler and other (1988). and Wheeler and McFeeley ( 1991) with modifications by the Canadian authors. For the northern part of the Russian Far East. the basic outcrop pattern is from So unov (1985) with modifications by the Russian authors. For the outhern part of the Russian Far East, the basic outcrop pattern is from Krasny (1991) and Bazhanov and Oleinik ( 1986) with

  8. Observing plants dealing with soil water stress: Daily soil moisture fluctuations derived from polymer tensiometers

    NASA Astrophysics Data System (ADS)

    van der Ploeg, Martine; de Rooij, Gerrit

    2014-05-01

    fluctuations in water content changes, with both root water uptake and root water excretion. The magnitude of the water content change was in the same order for all treatments, thus suggesting compensatory uptake. References Bakker G, Van der Ploeg MJ, de Rooij GH, Hoogendam CW, Gooren HPA, Huiskes C, Koopal LK and Kruidhof H. New polymer tensiometers: Measuring matric pressures down to the wilting point. Vadose Zone J. 6: 196-202, 2007. Blackman PG and Davies WJ. Root to shoot communication in maize plants of the effects of soil drying. J. Exp. Bot. 36: 39-48, 1985. Davies WJ and Zhang J. Root signals and the regulation of growth and development of plants in drying soil. Annu. Rev. Plant Physiol. Plant Mol. Biol. 42: 55-76, 1991. Gollan T, Passioura JB and Munns R. Soil water status affects the stomatal conductance of fully turgid wheat and sunflower leafs. Aust. J. Plant Physiol. 13: 459-464, 1986. Gowing DJG, Davies WJ and Jones HG. A Positive Root-sourced Signal as an Indicator of Soil Drying in Apple, Malus x domestica Borkh. J. Exp. Bot. 41: 1535-1540, 1990. Grace J. Environmental controls of gas exchange in tropical rain forests. In: Press, M.C, J.D. Scholes and M.G. Barker (ed.). Physiological plant ecology: the 39th Symposium of the British Ecological Society. Blackwell Science, United Kingdom, 1999. Kool D, Agam N, Lazarovitch N, Heitman JL, Sauer TJ, Ben-Gal A. A review of approaches for evapotranspiration partitioning. Agricultural and Forest Meteorology 184: 56- 70, 2014. Mansfield TA and De Silva DLR. Sensory systems in the roots of plants and their role in controlling stomatal function in the leaves. Physiol. Chem. Phys. & Med. 26: 89-99, 1994. Sadras VO and Milroy SP. Soil-water thresholds for the responses of leaf expansion and gas exchange: a review. Field Crops Res. 47: 253-266, 1996. Schröder N, Lazarovitch N, Vanderborcht J, Vereecken H, Javaux M. Linking transpiration reduction to rhizosphere salinity using a 3D coupled soil-plant model. Plant Soil 2013

  9. Evaluation Of Microdosing Strategies For Studies In Preclinical Drug Development: Demonstration Of Linear Pharmacokinetics In Dogs Of A Nucleoside Analogue Over A 50-Fold Dose Range

    SciTech Connect

    Sandhu, P; Vogel, J S; Rose, M J; Ubick, E A; Brunner, J E; Wallace, M A; Adelsberger, J K; Baker, M P; Henderson, P T; Pearson, P G; Baillie, T A

    2004-04-22

    (Stafford et al., 1984; Vogel et al., 1990; Smith et al., 1999) to its use as a bioanalytical tool for nutritional research (Buchholz et al., 1999; Deuker et al., 2000; Weaver and Liebman, 2002). Biomedical applications of AMS and its use in the arena of pharmaceutical research also have been detailed in review articles (Barker and Garner, 1999; Garner, 2000; Turteltaub and Vogel, 2000). To date, most studies on the metabolism and disposition of xenobiotics by AMS have focused on how carcinogens bind to DNA and proteins to form adducts (Turteltaub et al., 1990, 1997; Frantz et al., 1995; Dingley et al., 1999; Li et al., 2003). Its application to the field of pharmaceutical sciences has been limited to a few studies (Kaye et al., 1997; Young et al., 2001; Garner et al., 2002). However, the pharmaceutical industry is becoming increasingly aware of the potential benefits that may accrue from the ultra high sensitivity afforded by AMS in terms of evaluating the pharmacokinetics of lead drug candidates in early development. Specifically, AMS allows administration of sub-pharmacological doses (microdoses) of carbon-14 or tritium-labeled investigational drugs to animals or humans at radiologically insignificant levels with the goal of obtaining preliminary information regarding the absorption, distribution, metabolism, and excretion of test compounds (Turteltaub and Vogel, 2000). An unresolved issue, however, is whether the pharmacokinetics determined following a microdose are representative of those following a conventional (pharmacological) dose (Lappin and Garner, 2003). This paper examines the linearity of kinetics of an antiviral nucleoside analogue, Compound A, across sub-pharmacological and pharmacological dose ranges in the dog prior to initiation of a human microdose study. The specific objectives of this study, therefore, were (1) to assess the pharmacokinetics of Compound A in dogs by a conventional dosing approach utilizing LC-MS/MS for sample analysis, (2) to assess

  10. EDITORIAL: Focus on Cold and Ultracold Molecules FOCUS ON COLD AND ULTRACOLD MOLECULES

    NASA Astrophysics Data System (ADS)

    Carr, Lincoln D.; Ye, Jun

    2009-05-01

    öhlich, A Griesmaier, T Pfau, H Saito, Y Kawaguchi and M Ueda High-energy-resolution molecular beams for cold collision studies L P Parazzoli, N Fitch, D S Lobser and H J Lewandowski Collisional effects in the formation of cold guided beams of polar molecules M Motsch, C Sommer, M Zeppenfeld, L D van Buuren, P W H Pinkse and G Rempe Towards sympathetic cooling of large molecules: cold collisions between benzene and rare gas atoms P Barletta, J Tennyson and P F Barker Efficient formation of ground-state ultracold molecules via STIRAP from the continuum at a Feshbach resonance Elena Kuznetsova, Marko Gacesa, Philippe Pellegrini, Susanne F Yelin and Robin Côté Emergent timescales in entangled quantum dynamics of ultracold molecules in optical lattices M L Wall and L D Carr Rotational state resolved photodissociation spectroscopy of translationally and vibrationally cold MgH+ ions: toward rotational cooling of molecular ions K Højbjerre, A K Hansen, P S Skyt, P F Staanum and M Drewsen Collective transverse cavity cooling of a dense molecular beam Thomas Salzburger and Helmut Ritsch A Stark decelerator on a chip Samuel A Meek, Horst Conrad and Gerard Meijer Deceleration of molecules by dipole force potential: a numerical simulation Susumu Kuma and Takamasa Momose Ultracold molecules: vehicles to scalable quantum information processing Kathy-Anne Brickman Soderberg, Nathan Gemelke and Cheng Chin Magnetic field modification of ultracold molecule-molecule collisions T V Tscherbul, Yu V Suleimanov, V Aquilanti and R V Krems Spectroscopy of 39K85Rb triplet excited states using ultracold a 3Σ+ state molecules formed by photoassociation J T Kim, D Wang, E E Eyler, P L Gould and W C Stwalley Pumping vortex into a Bose-Einstein condensate of heteronuclear molecules Z F Xu, R Q Wang and L You Intense atomic and molecular beams via neon buffer-gas cooling David Patterson, Julia Rasmussen and John M Doyle Dynamical properties of dipolar Fermi gases T Sogo, L He, T Miyakawa, S Yi, H Lu

  11. An prediction and explanation of 'climatic swing

    NASA Astrophysics Data System (ADS)

    Barkin, Yury

    2010-05-01

    of RAS, Syktyvkar, pp. 26-28. In Russian. [7] Barkin Yu.V. (2009) Prediction and explanation of mean sea levels in northern hemisphere, in southern hemisphere and all ocean of the Earth. EGU General Assembly (Vienna, Austria, 19-24 April 2009). Geophysical Research Abstracts, Volume 11, 2009, abstract # EGU2009-1610. [8] Barkin Yu.V. (2007) Forced redistribution of air masses between southern and northern hemispheres of the Earth. Proceedings of IUGG XXIV General Assembly, Perugia, Italy 2007: Earth: Our Changing Planet (Perugia, Italy, July 2-13, 2007), (A)-IAGA, JAS008, p. 326. www. iugg2007perugia.it. [9] Barkin, Yu.V.; Shuanggen J. (2007) On variations of the mean radius of the Northern and Southern Hemispheres of the Earth. EGU General Assembly (Vienna, Austria, 15-20 April 2007). Geoph. Res. Abs., Vol. 9, 2007, abstract # EGU07-A-08183. [10] Stephen Barker, Paula Diz, Maryline J. Vautravers, Jennifer Pike, Gregor Knorr, Ian R. Hall & Wallace S. Broecker (2009) Interhemispheric Atlantic seesaw response during the last deglaciation. Nature, 457, 1097-1102 (26 February 2009) | doi:10.1038/nature07770.

  12. PREFACE: The IARU International Scientific Congress on Climate Change: Global Risks, Challenges and Decisions (10-12 March, Copenhagen, Denmark)

    NASA Astrophysics Data System (ADS)

    2009-01-01

    by the IARU universities In keeping with normal scientific practice, a procedure for producing the synthesis report that has been adopted optimises the chances of arriving at a product that will receive a broad backing from the scientific community as being a message that can be sent to the non-scientific community and that explains current understanding in climate change science The Writing Team will also be responsible for writing the book Members of the Writing Team (in alphabetical order) Professor Joe Alcamo, University of Stellenbosch Dr Terry Barker, Cambridge University Professor Daniel Kammen, University of California - Berkeley Professor Rik Leemans, Environmental Systems Analysis Group, Wageningen University Professor Diana Liverman, Oxford University Professor Mohan Munasinghe, Chairman, Munasinghe Institute for Development (MIND) Dr Balgis Osman-Elasha, Higher Council for Environment and Natural Resources (HCENR), Sudan Professor Katherine Richardson, University of Copenhagen Professor John Schellnhuber, Potsdam Institute for Climate Impact Research and visiting professor at the University of Oxford Professor Will Steffen, Australian National University Professor Lord Nicholas Stern, London School of Economics and Political Science (LSE) Professor Ole Wæver, University of Copenhagen 2 Key Messages from the Congress Key Message 1: Climatic Trends Recent observations confirm that, given high rates of observed emissions, the worst-case IPCC scenario trajectories (or even worse) are being realized For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts Key