Science.gov

Sample records for elekriki haste shekafande

  1. High Altitude Supersonic Target (HAST), Phase 2

    DTIC Science & Technology

    1974-08-01

    Controlled Thrust Assembly 146 9. Fuel Grain 146 10. Nozzle and Aft Closure 146 11. Oxidizer Injector and Manifold 147 12. Igniter 150 13. Motor Case... Motor Case 152 84 Recovery System Deployment Sequence 173 85 Ppjwhute System 176 86 HAST Main Parachute I76 87 Recovery Module I78 88 Safe and Arm...Station 197.50. The frame assembly is attached to the motor case with flush structural screws. A 304 stainless steel boattail cover a’tach?« tO the «ft

  2. Disrupting the Education Monopoly: A Conversation with Reed Hastings

    ERIC Educational Resources Information Center

    Jacobs, Joanne

    2015-01-01

    This article features an interview with Netflix CEO, Reed Hastings. In this interview, Hastings relates that he told the "Wall Street Journal" in 2008 that he started looking at education--trying to figure out why our education is lagging when our technology is increasing at great rates and there's great innovation in so many other areas…

  3. Disrupting the Education Monopoly: A Conversation with Reed Hastings

    ERIC Educational Resources Information Center

    Jacobs, Joanne

    2015-01-01

    This article features an interview with Netflix CEO, Reed Hastings. In this interview, Hastings relates that he told the "Wall Street Journal" in 2008 that he started looking at education--trying to figure out why our education is lagging when our technology is increasing at great rates and there's great innovation in so many other areas…

  4. VIEW OF PIEDMONT AVENUE AT INTERSECTION OF HASTE STREET, CHATEAU ...

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

    VIEW OF PIEDMONT AVENUE AT INTERSECTION OF HASTE STREET, CHATEAU APARTMENTS BY CLARENCE CASEBOLT DAKIN, 1929 AT 2747 HASTE ON WEST SIDE OF PIEDMONT. LOOKING NORTH. Photograph by Fredrica Drotos and Michael Kelly, July 8, 2006 - Piedmont Way & the Berkeley Property Tract, East of College Avenue between Dwight Way & U.C. Memorial Stadium, Berkeley, Alameda County, CA

  5. E SERIES MAGAZINES FROM HASTINGS ST. SHOWING ACCESS DRIVE AND ...

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

    E SERIES MAGAZINES FROM HASTINGS ST. SHOWING ACCESS DRIVE AND LOADING PLATFORMS. E 103 MAGAZINES IN FORGROUND. - Naval Magazine Lualualei, Headquarters Branch, Magazine Type, Eleventh, Thirteenth, Fifteenth, Sixteenth, & Seventeenth Streets, Pearl City, Honolulu County, HI

  6. Entanglement of random subspaces via the Hastings bound

    SciTech Connect

    Fukuda, Motohisa; King, Christopher

    2010-04-15

    Recently, Hastings ['A counterexample to additivity of minimum output entropy', Nat. Phys. 5, 255 (2009); e-print arXiv:0809.3972v3] proved the existence of random unitary channels, which violate the additivity conjecture. In this paper, we use Hastings' method to derive new bounds for the entanglement of random subspaces of bipartite systems. As an application we use these bounds to prove the existence of nonunital channels, which violate additivity of minimal output entropy.

  7. The Lady Hastings' Charity Schools: Accounting for Eighteenth-Century Rural Philanthropy.

    ERIC Educational Resources Information Center

    Baker, Mae

    1997-01-01

    Describes the philanthropic activities of Lady Elizabeth Hastings and the local provision of rural charity schools in 18th-century England. Covers Hastings' background, her establishment of girls' charity schools, charity-school curricula, the Society for the Promotion of Christian Knowledge, and charity-school teachers. Evaluates Hastings'…

  8. VIEW OF PIEDMONT AVENUE AT INTERSECTION OF HASTE STREET, NOTE ...

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

    VIEW OF PIEDMONT AVENUE AT INTERSECTION OF HASTE STREET, NOTE RECONSTRUCTION OF MEDIAN FROM PREVIOUS VIEW IN PHOTOGRAPH CA-2-5. LOOKING NW. Photograph by Brian Grogan, July 8, 2007 - Piedmont Way & the Berkeley Property Tract, East of College Avenue between Dwight Way & U.C. Memorial Stadium, Berkeley, Alameda County, CA

  9. The surgeon's assistant: an orthopaedic model at Hastings.

    PubMed

    Stenhouse, N; Gallannaugh, S C

    1996-07-01

    An Orthopaedic Surgeon's Assistant has been part of the orthopaedic surgical team at Hastings since 1983. Having a suitably trained person in post ensures continuity and stability and enhances the treatment of patients, the performance of the department and the training offered to Higher Surgical Trainees. Discussion includes the value of such a role, other orthopaedic models and the need for a nationally accredited training scheme and qualification.

  10. The Infrared Signature of the High Altitude Supersonic Target (HAST) at Sea Level

    DTIC Science & Technology

    1975-08-01

    second and is the propilsion system for the HAST. A subscale engine having the s same general geometry and propellants , and operating at a flow rate of...total mass flow rates of about 5 to 10 percent of that of the HAST engine total propellant flow rate. Further increases of the secondary mass flow rate...by a constant amount. This is due entirely to aspect angle. The HAST propellant exhaust is highly rich in fuel and particulates and thus is quite

  11. The Hastings Center and the early years of bioethics.

    PubMed

    Callahan, Daniel

    2012-02-01

    The Hastings Center was founded in 1969 to study ethical problems in medicine and biology. The Center arose from a confluence of three social currents: the increased public scrutiny of medicine and its practices, the concern about the moral problems being generated by technological developments, and the desire of one of its founders (Callahan) to make use of his philosophical training in a more applied way. The early years of the Center were devoted to raising money, developing an early agenda of issues, and identifying a cadre of people around the country interested in the issues. Various stresses and strains in the Center and the field are identified, and some final reflections are offered on the nature and value of the contributions made by bioethics as an academic field.

  12. A general construction for parallelizing Metropolis-Hastings algorithms.

    PubMed

    Calderhead, Ben

    2014-12-09

    Markov chain Monte Carlo methods (MCMC) are essential tools for solving many modern-day statistical and computational problems; however, a major limitation is the inherently sequential nature of these algorithms. In this paper, we propose a natural generalization of the Metropolis-Hastings algorithm that allows for parallelizing a single chain using existing MCMC methods. We do so by proposing multiple points in parallel, then constructing and sampling from a finite-state Markov chain on the proposed points such that the overall procedure has the correct target density as its stationary distribution. Our approach is generally applicable and straightforward to implement. We demonstrate how this construction may be used to greatly increase the computational speed and statistical efficiency of a variety of existing MCMC methods, including Metropolis-Adjusted Langevin Algorithms and Adaptive MCMC. Furthermore, we show how it allows for a principled way of using every integration step within Hamiltonian Monte Carlo methods; our approach increases robustness to the choice of algorithmic parameters and results in increased accuracy of Monte Carlo estimates with little extra computational cost.

  13. A general construction for parallelizing Metropolis−Hastings algorithms

    PubMed Central

    Calderhead, Ben

    2014-01-01

    Markov chain Monte Carlo methods (MCMC) are essential tools for solving many modern-day statistical and computational problems; however, a major limitation is the inherently sequential nature of these algorithms. In this paper, we propose a natural generalization of the Metropolis−Hastings algorithm that allows for parallelizing a single chain using existing MCMC methods. We do so by proposing multiple points in parallel, then constructing and sampling from a finite-state Markov chain on the proposed points such that the overall procedure has the correct target density as its stationary distribution. Our approach is generally applicable and straightforward to implement. We demonstrate how this construction may be used to greatly increase the computational speed and statistical efficiency of a variety of existing MCMC methods, including Metropolis-Adjusted Langevin Algorithms and Adaptive MCMC. Furthermore, we show how it allows for a principled way of using every integration step within Hamiltonian Monte Carlo methods; our approach increases robustness to the choice of algorithmic parameters and results in increased accuracy of Monte Carlo estimates with little extra computational cost. PMID:25422442

  14. 75 FR 45011 - MainStreet Savings Bank, FSB, Hastings, MI; Notice of Appointment of Receiver

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-30

    ... [Federal Register Volume 75, Number 146 (Friday, July 30, 2010)] [Notices] [Page 45011] [FR Doc No: 2010-18612] DEPARTMENT OF THE TREASURY Office of Thrift Supervision MainStreet Savings Bank, FSB... appointed the Federal Deposit Insurance Corporation as sole Receiver for MainStreet Savings Bank, Hastings...

  15. 76 FR 72867 - Proposed Amendment of Class E Airspace; Hastings, NE

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-28

    ... necessary to accommodate new Standard Instrument Approach Procedures (SIAP) at Hastings Municipal Airport... New Jersey Avenue SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-0001. You must... amending Class E airspace extending upward from 700 feet above the surface to accommodate new standard...

  16. Recreational Development and Fish and Wildlife Enhancement, Lake Rebecca, Hastings, Minnesota.

    DTIC Science & Technology

    1978-03-01

    birdlife, primarily because it is the main stem of the Mississippi flyway and within an area of overlapping eastern and western ornithological ranges...Historical Society has been consulted for cultural resources located in the Hastings vicinity. There are a number of prehistoric, historic, and...Park Commission Minnesota Pollution Control Agency Minnesota Historical Society Minnesota Water Resources Board Minnesota State Archaeologist

  17. Metropolis-Hastings Robbins-Monro Algorithm for Confirmatory Item Factor Analysis

    ERIC Educational Resources Information Center

    Cai, Li

    2010-01-01

    Item factor analysis (IFA), already well established in educational measurement, is increasingly applied to psychological measurement in research settings. However, high-dimensional confirmatory IFA remains a numerical challenge. The current research extends the Metropolis-Hastings Robbins-Monro (MH-RM) algorithm, initially proposed for…

  18. High-Dimensional Exploratory Item Factor Analysis by a Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Cai, Li

    2010-01-01

    A Metropolis-Hastings Robbins-Monro (MH-RM) algorithm for high-dimensional maximum marginal likelihood exploratory item factor analysis is proposed. The sequence of estimates from the MH-RM algorithm converges with probability one to the maximum likelihood solution. Details on the computer implementation of this algorithm are provided. The…

  19. Metropolis-Hastings Robbins-Monro Algorithm for Confirmatory Item Factor Analysis

    ERIC Educational Resources Information Center

    Cai, Li

    2010-01-01

    Item factor analysis (IFA), already well established in educational measurement, is increasingly applied to psychological measurement in research settings. However, high-dimensional confirmatory IFA remains a numerical challenge. The current research extends the Metropolis-Hastings Robbins-Monro (MH-RM) algorithm, initially proposed for…

  20. High-Dimensional Exploratory Item Factor Analysis by a Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Cai, Li

    2010-01-01

    A Metropolis-Hastings Robbins-Monro (MH-RM) algorithm for high-dimensional maximum marginal likelihood exploratory item factor analysis is proposed. The sequence of estimates from the MH-RM algorithm converges with probability one to the maximum likelihood solution. Details on the computer implementation of this algorithm are provided. The…

  1. Selected water-quality characteristics in the upper Mississippi River basin, Royalton to Hastings, Minnesota

    USGS Publications Warehouse

    Have, M.R.

    1991-01-01

    Results of this study show that the quality of water in the Mississippi River as it leaves the accounting unit at Hastings is not representative of water quality in most of the accounting unit. Three water-quality regions have been identified, and sampling sites are needed in each region to assess the quality of streams throughout the study area adequately.

  2. Placental function assessed visually using half-Fourier acquisition single-shot turbo spin-echo (HASTE) magnetic resonance imaging.

    PubMed

    Himoto, Yuki; Kido, Aki; Mogami, Haruta; Moribata, Yusaku; Minamiguchi, Sachiko; Shitano, Fuki; Kiguchi, Kayo; Kurata, Yasuhisa; Konishi, Ikuo; Togashi, Kaori

    2016-03-01

    To investigate a simple visual assessment method of placental function using half-Fourier acquisition single-shot turbo spin-echo (HASTE) magnetic resonance imaging (MRI). The institutional review board approved this retrospective study of fetal MRI in 48 singleton pregnant women for whom placentas had undergone clinical pathological examinations. Two readers independently assessed the placentas using the HASTE scoring system, particularly emphasizing the visualization of the regular two-tone pattern inside and signal intensity (SI) of placental parenchyma referring to SI of the fetal kidney and liver. After categorization using the HASTE scoring system, the associations between the scores and the presence of pathologically proven placental insufficiency or of low birth weight less than the tenth percentile were examined using chi-square tests. The associations between the HASTE scores and the MRI findings previously reported to suggest placental insufficiency, such as placental thickness and placenta to amniotic fluid SI ratio, were also examined using Student t-tests. The HASTE scores were associated significantly with the presence of pathologically proven placental insufficiency (P = .003 for reader 1; P = .04 reader 2) and birth weight less than the tenth percentile (P = .005 for reader 1; P = .003 for reader 2). The HASTE scores were associated significantly with the placenta thickness (P < .0001 for both readers) and the placenta to the amniotic fluid SI ratio (P < .0001 for both readers). The HASTE scoring system is feasible for use in clinical assessment of placental function and for diagnosing placental insufficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. MODELING OF THE INITIAL MASS FUNCTION USING THE METROPOLIS-HASTINGS ALGORITHM

    SciTech Connect

    Chattopadhyay, Tanuka; Chattopadhyay, Asis Kumar; Sinha, Abisa E-mail: akcstat@caluniv.ac.in

    2011-08-01

    A stochastic model has been developed for the hierarchical fragmentation of a molecular cloud. Here, the number of fragments, time between successive fragmentation steps, and mass of a fragment are considered as random variables, and fragment masses are generated using the Metropolis-Hastings algorithm. The resulting mass spectra, computed at different projected distances and taking opacity into consideration, show a signature of mass segregation. The critical mass, mass spectrum, and mass segregation are consistent with the observations of young massive clusters in our Galaxy as well as in external galaxies.

  4. [Diagnostic value of HASTE technique and excretory MR urography in urinary system obstructions].

    PubMed

    Erdoğmuş, Beşir; Bozkurt, Mahmut; Bakir, Zeki

    2004-12-01

    To compare the diagnostic value of static-liquid magnetic resonance urography (MRU) in T2-weighted HASTE (half-fourier acquisition single-shot turbo spinecho) sequences and T1-weighted excretory MRU with i.v. diuretic and contrast material injection. The study included 29 patients (15 men, 14 women). Thirty-one urinary obstructions were detected on intravenous urography (IVU) two of which were due to bilateral obstructions. The cases were evaluated by T2 HASTE sequences combined with T1-weighted FLASH 3D sequences after i.v. diuretics and gadolinium DTPA injection. Thirty-one urinary obstructions were detected on IVU. Thirty of which were confirmed by T2-weighted MRU and all were confirmed by excretory MRU. In one nonobstructive case, unilateral grade 1 ureteropelvicaliectasis related to ureteral stone was falsely interpreted by both sequences. There were no statistical differences among IVU, T2-weighted MRU and excretory MRU in detecting the obstruction levels. In 22 cases with ureteral stones, 12 of which were confirmed by T2-weighted MRU and 18 cases were confirmed by excretory MRU. Sensitivity and specificity fo detecting the ureteral stones as a cause of obstruction with T2-weighted MRU were 50%and 89% and with excretory MRU were 77% and 89% respectively. In 9 obstructive cases due to causes other than the stones, 8 of which were detected by T2-weighted MRU and all of which were detected by excretory MRU. Sensitivity and specificity for detecting the causes other than the stones with T2-weighted MRU were 96% and 100% and with excretory MRU were 100% and 100% respectively. MRU is a useful thechnique revealing high-quality images to determine the urinary system obstructions to obtain the causes of obstructions. MRU should be used as an alternative imaging technique in cases which IVU can not be applied. The existence and the causes of obstruction can be detected by HASTE MRU. Excretory MRU can supply additional information in cases with functional kidneys where

  5. Hastings Center

    MedlinePlus

    ... Share: Read more BIOETHICS FORUM ESSAY The Symbolic Value of the Bioethics and Populism Debate Read more ... is deeply troubling under international law and humanitarian values. Under the 1967… Read more Share: Read more ...

  6. A Monte Carlo Metropolis-Hastings algorithm for sampling from distributions with intractable normalizing constants.

    PubMed

    Liang, Faming; Jin, Ick-Hoon

    2013-08-01

    Simulating from distributions with intractable normalizing constants has been a long-standing problem in machine learning. In this letter, we propose a new algorithm, the Monte Carlo Metropolis-Hastings (MCMH) algorithm, for tackling this problem. The MCMH algorithm is a Monte Carlo version of the Metropolis-Hastings algorithm. It replaces the unknown normalizing constant ratio by a Monte Carlo estimate in simulations, while still converges, as shown in the letter, to the desired target distribution under mild conditions. The MCMH algorithm is illustrated with spatial autologistic models and exponential random graph models. Unlike other auxiliary variable Markov chain Monte Carlo (MCMC) algorithms, such as the Møller and exchange algorithms, the MCMH algorithm avoids the requirement for perfect sampling, and thus can be applied to many statistical models for which perfect sampling is not available or very expensive. The MCMH algorithm can also be applied to Bayesian inference for random effect models and missing data problems that involve simulations from a distribution with intractable integrals.

  7. General Metropolis-Hastings jump diffusions for automatic target recognition in infrared scenes

    NASA Astrophysics Data System (ADS)

    Lanterman, Aaron D.; Miller, Michael I.; Snyder, Donald L.

    1997-04-01

    To locate and recognize ground-based targets in forward- looking IR (FLIR) images, 3D faceted models with associated pose parameters are formulated to accommodate the variability found in FLIR imagery. Taking a Bayesian approach, scenes are simulated from the emissive characteristics of the CAD models and compared with the collected data by a likelihood function based on sensor statistics. This likelihood is combined with a prior distribution defined over the set of possible scenes to form a posterior distribution. To accommodate scenes with variable numbers of targets, the posterior distribution is defined over parameter vectors of varying dimension. An inference algorithm based on Metropolis-Hastings jump- diffusion processes empirically samples from the posterior distribution, generating configurations of templates and transformations that match the collected sensor data with high probability. The jumps accommodate the addition and deletion of targets and the estimation of target identities; diffusions refine the hypotheses by drifting along the gradient of the posterior distribution with respect to the orientation and position parameters. Previous results on jumps strategies analogous to the Metropolis acceptance/rejection algorithm, with proposals drawn from the prior and accepted based on the likelihood, are extended to encompass general Metropolis-Hastings proposal densities. In particular, the algorithm proposes moves by drawing from the posterior distribution over computationally tractible subsets of the parameter space. The algorithm is illustrated by an implementation on a Silicon Graphics Onyx/Reality Engine.

  8. 76 FR 58241 - Designation for the Aberdeen, SD; Decatur, IL; Hastings, NE; Fulton, IL; the State of Missouri...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ... services under the United States Grain Standards Act, as amended (USGSA). DATES: Effective Date: October 1... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF AGRICULTURE...; Hastings, NE; Fulton, IL; the State of Missouri, and the State of South Carolina Areas AGENCY:...

  9. Estimation of Contextual Effects through Nonlinear Multilevel Latent Variable Modeling with a Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Yang, Ji Seung; Cai, Li

    2014-01-01

    The main purpose of this study is to improve estimation efficiency in obtaining maximum marginal likelihood estimates of contextual effects in the framework of nonlinear multilevel latent variable model by adopting the Metropolis-Hastings Robbins-Monro algorithm (MH-RM). Results indicate that the MH-RM algorithm can produce estimates and standard…

  10. Efficient implementation of the Metropolis-Hastings algorithm, with application to the Cormack?Jolly?Seber model

    USGS Publications Warehouse

    Link, W.A.; Barker, R.J.

    2008-01-01

    Judicious choice of candidate generating distributions improves efficiency of the Metropolis-Hastings algorithm. In Bayesian applications, it is sometimes possible to identify an approximation to the target posterior distribution; this approximate posterior distribution is a good choice for candidate generation. These observations are applied to analysis of the Cormack?Jolly?Seber model and its extensions.

  11. Efficient implementation of the Metropolis-Hastings algorithm, with application to the Cormack-Jolly-Seber model

    USGS Publications Warehouse

    Link, W.A.; Barker, R.J.

    2008-01-01

    Judicious choice of candidate generating distributions improves efficiency of the Metropolis-Hastings algorithm. In Bayesian applications, it is sometimes possible to identify an approximation to the target posterior distribution; this approximate posterior distribution is a good choice for candidate generation. These observations are applied to analysis of the Cormack-Jolly-Seber model and its extensions. ?? Springer Science+Business Media, LLC 2007.

  12. Estimation of Contextual Effects through Nonlinear Multilevel Latent Variable Modeling with a Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Yang, Ji Seung; Cai, Li

    2014-01-01

    The main purpose of this study is to improve estimation efficiency in obtaining maximum marginal likelihood estimates of contextual effects in the framework of nonlinear multilevel latent variable model by adopting the Metropolis-Hastings Robbins-Monro algorithm (MH-RM). Results indicate that the MH-RM algorithm can produce estimates and standard…

  13. A Sanctuary for Science: The Hastings Natural History Reservation and the Origins of the University of California's Natural Reserve System.

    PubMed

    Alagona, Peter S

    2012-01-01

    In 1937 Joseph Grinnell founded the University of California's (U.C.) first biological field station, the Hastings Natural History Reservation. Hastings became a center for field biology on the West Coast, and by 1960 it was serving as a model for the creation of additional U.C. reserves. Today, the U.C. Natural Reserve System (NRS) is the largest and most diverse network of university-based biological field stations in the world, with 36 sites covering more than 135,000 acres. This essay examines the founding of the Hastings Reservation, and asks how it managed to grow and develop, in the 1940s and 1950s, during a time of declining support for natural history research. It shows how faculty and staff courted the support of key institutional allies, presented themselves as the guardians of a venerable tradition in nature study, and emphasized the station's capacity to document ecological change and inform environmental policy and management. In the years since, Hastings and other U.C. reserves have played crucial roles in California environmental politics. Biological field stations in the post-war era deserve more attention not only from historians of biology, but also from environmental historians and other scholars interested in the role of science in society.

  14. Metropolis–Hastings thermal state sampling for numerical simulations of Bose–Einstein condensates

    PubMed Central

    Grišins, Pjotrs; Mazets, Igor E.

    2014-01-01

    We demonstrate the application of the Metropolis–Hastings algorithm to sampling of classical thermal states of one-dimensional Bose–Einstein quasicondensates in the classical fields approximation, both in untrapped and harmonically trapped case. The presented algorithm can be easily generalized to higher dimensions and arbitrary trap geometry. For truncated Wigner simulations the quantum noise can be added with conventional methods (half a quantum of energy in every mode). The advantage of the presented method over the usual analytical and stochastic ones lies in its ability to sample not only from canonical and grand canonical distributions, but also from the generalized Gibbs ensemble, which can help to shed new light on thermodynamics of integrable systems. PMID:25843966

  15. The Polya Tree Sampler: Towards Efficient and Automatic Independent Metropolis-Hastings Proposals.

    PubMed

    Hanson, Timothy E; Monteiro, João V D; Jara, Alejandro

    2011-03-01

    We present a simple, efficient, and computationally cheap sampling method for exploring an un-normalized multivariate density on ℝ(d), such as a posterior density, called the Polya tree sampler. The algorithm constructs an independent proposal based on an approximation of the target density. The approximation is built from a set of (initial) support points - data that act as parameters for the approximation - and the predictive density of a finite multivariate Polya tree. In an initial "warming-up" phase, the support points are iteratively relocated to regions of higher support under the target distribution to minimize the distance between the target distribution and the Polya tree predictive distribution. In the "sampling" phase, samples from the final approximating mixture of finite Polya trees are used as candidates which are accepted with a standard Metropolis-Hastings acceptance probability. Several illustrations are presented, including comparisons of the proposed approach to Metropolis-within-Gibbs and delayed rejection adaptive Metropolis algorithm.

  16. Metropolis-Hastings thermal state sampling for numerical simulations of Bose-Einstein condensates.

    PubMed

    Grišins, Pjotrs; Mazets, Igor E

    2014-07-01

    We demonstrate the application of the Metropolis-Hastings algorithm to sampling of classical thermal states of one-dimensional Bose-Einstein quasicondensates in the classical fields approximation, both in untrapped and harmonically trapped case. The presented algorithm can be easily generalized to higher dimensions and arbitrary trap geometry. For truncated Wigner simulations the quantum noise can be added with conventional methods (half a quantum of energy in every mode). The advantage of the presented method over the usual analytical and stochastic ones lies in its ability to sample not only from canonical and grand canonical distributions, but also from the generalized Gibbs ensemble, which can help to shed new light on thermodynamics of integrable systems.

  17. Dynamical behavior of fractional-order Hastings-Powell food chain model and its discretization

    NASA Astrophysics Data System (ADS)

    Matouk, A. E.; Elsadany, A. A.; Ahmed, E.; Agiza, H. N.

    2015-10-01

    In this work, the dynamical behavior of fractional-order Hastings-Powell food chain model is investigated and a new discretization method of the fractional-order system is introduced. A sufficient condition for existence and uniqueness of the solution of the proposed system is obtained. Local stability of the equilibrium points of the fractional-order system is studied. Furthermore, the necessary and sufficient conditions of stability of the discretized system are also studied. It is shown that the system's fractional parameter has effect on the stability of the discretized system which shows rich variety of dynamical behaviors such as Hopf bifurcation, an attractor crisis and chaotic attractors. Numerical simulations show the tea-cup chaotic attractor of the fractional-order system and the richer dynamical behavior of the corresponding discretized system.

  18. Time Lapse Gravity and Seismic Monitoring of CO2 Injection at the West Hastings Field, Texas

    NASA Astrophysics Data System (ADS)

    Ferguson, J. F.; Richards, T.; Klopping, F.; MacQueen, J.; Hosseini, S. A.

    2015-12-01

    Time lapse or 4D gravity and seismic reflection surveys are being conducted at the West Hastings Field near Houston, Texas to monitor the progress of CO2 injection. This Department of Energy supported CO2 sequestration experiment is conducted in conjunction with a Denbury Onshore, LLC tertiary recovery project. The reservoir is at a depth of 1.8 km in the Oligocene Frio sands and has been produced since the 1930s. Goals are an accounting and mapping of the injected CO2 and to determine if migration occurs along intra-reservoir faults. An integrated interpretation of the geophysical surveys will be made together with well logs and engineering data. Gravity monitoring of water versus gas replacement has been very successful, but liquid phase CO2 monitoring is problematic due to the smaller density contrast with respect to oil and water. This reservoir has a small volume to depth ratio and hence only a small gravity difference signal is expected on the surface. New borehole gravity technology introduced by Micro-g-Lacoste can make gravity measurements at near reservoir depths with a much higher signal to noise ratio. This method has been successfully evaluated on a simulation of the Hastings project. Field operations have been conducted for repeated surface and borehole gravity surveys beginning in 2013. The surface survey of 95 stations covers an area of 3 by 5 km and 22 borehole gravity logs are run in the interval above the Frio formation. 4D seismic reflection surveys are being made at 6 month intervals on the surface and in 3 VSP wells. CO2 injection into the targeted portion of the reservoir only began in early 2015 and monitoring will continue into 2017. To date only the baseline reservoir conditions have been assessed. The overall success of the gravity monitoring will not be determined until 2017.

  19. Acute ureteric calculus obstruction: unenhanced spiral CT versus HASTE MR urography and abdominal radiograph.

    PubMed

    Regan, F; Kuszyk, B; Bohlman, M E; Jackman, S

    2005-06-01

    The aim of this study is to compare the performance of unenhanced spiral CT to the combination of HASTE MR urography (MRU) and plain abdominal radiography (KUB) in patients suspected of having acute calculus ureteric obstruction. 64 patients with suspected acute calculus ureteric obstruction were evaluated. The presence of perirenal fluid, presence and level of ureteric obstruction and calculi were assessed on both techniques. 44 of 64 (69%) patients had acute calculus ureteric obstruction based on clinical, radiographic or surgical findings. MRU showed perirenal fluid in acute ureteric obstruction (77%) with a greater sensitivity than CT showed stranding (45%). The combination of fluid and ureteric dilation on MRU showed a sensitivity of 93% (CT 80%), specificity of 95% (CT 85%), and accuracy of 94% (CT 81%). There were 61 findings of either fluid or ureteric dilatation on MRU in 44 acutely obstructed kidneys compared with 37 similar findings on CT (p<0.005). Although there was excellent reproducibility (Kappa=/>0.75) in the finding of perirenal fluid on MRU, there was only fair interobserver agreement (Kappa<0.4) regarding perirenal stranding on CT. MRU/KUB showed ureteric calculi in 21/29 (72%) of patients with calculi seen by CT. Overall, MRU/KUB revealed 2.4 abnormalities per acutely obstructed ureter compared with 1.8 abnormalities detected by CT. MRU/KUB using HASTE sequences can diagnose the presence of acute calculus ureteric obstruction with similar accuracy to spiral CT. The technique has less observer variability and is more accurate than CT in detecting evidence of obstruction such as perirenal fluid.

  20. A Preliminary Archaeological Survey of a Proposed Recreational Development and Fish and Wildlife Enhancement Project in Lake Rebecca, Hastings, Minnesota,

    DTIC Science & Technology

    1978-01-01

    of the proposed recreation area on the shores of Lake Rebecca, in Iastings, Minnesota. Almost all of the proposed construction will be confined to the...across Section 21 of Hastings Township, Township 115N Range 17W, Dakota County, Minnesota. The proposed development includes the construction of roads...proposed construction . Of special interest was an evaluation of the areas to be flooded and the foundations on the eastern side of the lake in the park. A

  1. Chaos control of Hastings-Powell model by combining chaotic motions

    NASA Astrophysics Data System (ADS)

    Danca, Marius-F.; Chattopadhyay, Joydev

    2016-04-01

    In this paper, we propose a Parameter Switching (PS) algorithm as a new chaos control method for the Hastings-Powell (HP) system. The PS algorithm is a convergent scheme that switches the control parameter within a set of values while the controlled system is numerically integrated. The attractor obtained with the PS algorithm matches the attractor obtained by integrating the system with the parameter replaced by the averaged value of the switched parameter values. The switching rule can be applied periodically or randomly over a set of given values. In this way, every stable cycle of the HP system can be approximated if its underlying parameter value equalizes the average value of the switching values. Moreover, the PS algorithm can be viewed as a generalization of Parrondo's game, which is applied for the first time to the HP system, by showing that losing strategy can win: "losing + losing = winning." If "loosing" is replaced with "chaos" and, "winning" with "order" (as the opposite to "chaos"), then by switching the parameter value in the HP system within two values, which generate chaotic motions, the PS algorithm can approximate a stable cycle so that symbolically one can write "chaos + chaos = regular." Also, by considering a different parameter control, new complex dynamics of the HP model are revealed.

  2. Chaos control of Hastings-Powell model by combining chaotic motions.

    PubMed

    Danca, Marius-F; Chattopadhyay, Joydev

    2016-04-01

    In this paper, we propose a Parameter Switching (PS) algorithm as a new chaos control method for the Hastings-Powell (HP) system. The PS algorithm is a convergent scheme that switches the control parameter within a set of values while the controlled system is numerically integrated. The attractor obtained with the PS algorithm matches the attractor obtained by integrating the system with the parameter replaced by the averaged value of the switched parameter values. The switching rule can be applied periodically or randomly over a set of given values. In this way, every stable cycle of the HP system can be approximated if its underlying parameter value equalizes the average value of the switching values. Moreover, the PS algorithm can be viewed as a generalization of Parrondo's game, which is applied for the first time to the HP system, by showing that losing strategy can win: "losing + losing = winning." If "loosing" is replaced with "chaos" and, "winning" with "order" (as the opposite to "chaos"), then by switching the parameter value in the HP system within two values, which generate chaotic motions, the PS algorithm can approximate a stable cycle so that symbolically one can write "chaos + chaos = regular." Also, by considering a different parameter control, new complex dynamics of the HP model are revealed.

  3. HASTE diffusion-weighted 3-Tesla magnetic resonance imaging in the diagnosis of primary and relapsing cholesteatoma.

    PubMed

    Pizzini, Francesca B; Barbieri, Franco; Beltramello, Alberto; Alessandrini, Franco; Fiorino, Francesco

    2010-06-01

    To evaluate the value of half-Fourier acquisition single-shot turbo-spin-echo diffusion-weighted magnetic resonance imaging (HASTE DW MRI) using a 3-Tesla (3T) unit in the diagnosis of primary and relapsing cholesteatoma. Retrospective observational investigation. Tertiary referral center. Seventeen patients suspected of having a primary cholesteatoma without clear clinical evidence of the lesion, and 13 patients who were candidates to a second-stage tympanoplasty to rule out a relapsing cholesteatoma or reconstruct the ossicular chain were investigated. All patients were scanned in a 3T scanner with a 4-channel head coil using T2 HASTE DW MRI technique sequences in axial and coronal planes covering the middle ear and mastoid regions. Images were considered positive for cholesteatoma in the presence of a hyperintense, patchy-like lesion in the petrous bone. Images showed a high signal intensity suggestive of primary cholesteatoma in 10 of 17 patients and of relapsing cholesteatoma in 7 of 13 patients. Of the 17 subjects, 15 with positive MRI findings were operated on, and the presence of cholesteatoma (ranging from 2 to 20 mm in size) was confirmed at surgery. Of the 13 subjects shown to be negative on HASTE DW MRI for cholesteatoma, 11 were operated on and were all confirmed to be cholesteatoma-free. Half-Fourier acquisition single-shot turbo-spin-echo diffusion-weighted magnetic resonance imaging technique, using a 3T unit, may be a diagnostic tool for a rapid and highly reliable discrimination between cholesteatomatous and noncholesteatomatous tissue in the middle ear, with 100% of positive and negative predictive values.

  4. Estimation of Contextual Effects through Nonlinear Multilevel Latent Variable Modeling with a Metropolis-Hastings Robbins-Monro Algorithm. CRESST Report 833

    ERIC Educational Resources Information Center

    Yang, Ji Seung; Cai, Li

    2013-01-01

    The main purpose of this study is to improve estimation efficiency in obtaining full-information maximum likelihood (FIML) estimates of contextual effects in the framework of a nonlinear multilevel latent variable model by adopting the Metropolis-Hastings Robbins-Monro algorithm (MH-RM; Cai, 2008, 2010a, 2010b). Results indicate that the MH-RM…

  5. Bayesian forecasting and uncertainty quantifying of stream flows using Metropolis-Hastings Markov Chain Monte Carlo algorithm

    NASA Astrophysics Data System (ADS)

    Wang, Hongrui; Wang, Cheng; Wang, Ying; Gao, Xiong; Yu, Chen

    2017-06-01

    This paper presents a Bayesian approach using Metropolis-Hastings Markov Chain Monte Carlo algorithm and applies this method for daily river flow rate forecast and uncertainty quantification for Zhujiachuan River using data collected from Qiaotoubao Gage Station and other 13 gage stations in Zhujiachuan watershed in China. The proposed method is also compared with the conventional maximum likelihood estimation (MLE) for parameter estimation and quantification of associated uncertainties. While the Bayesian method performs similarly in estimating the mean value of daily flow rate, it performs over the conventional MLE method on uncertainty quantification, providing relatively narrower reliable interval than the MLE confidence interval and thus more precise estimation by using the related information from regional gage stations. The Bayesian MCMC method might be more favorable in the uncertainty analysis and risk management.

  6. Bayesian forecasting and uncertainty quantifying of stream flows using Metropolis–Hastings Markov Chain Monte Carlo algorithm

    DOE PAGES

    Wang, Hongrui; Wang, Cheng; Wang, Ying; ...

    2017-04-05

    This paper presents a Bayesian approach using Metropolis-Hastings Markov Chain Monte Carlo algorithm and applies this method for daily river flow rate forecast and uncertainty quantification for Zhujiachuan River using data collected from Qiaotoubao Gage Station and other 13 gage stations in Zhujiachuan watershed in China. The proposed method is also compared with the conventional maximum likelihood estimation (MLE) for parameter estimation and quantification of associated uncertainties. While the Bayesian method performs similarly in estimating the mean value of daily flow rate, it performs over the conventional MLE method on uncertainty quantification, providing relatively narrower reliable interval than the MLEmore » confidence interval and thus more precise estimation by using the related information from regional gage stations. As a result, the Bayesian MCMC method might be more favorable in the uncertainty analysis and risk management.« less

  7. Evaluation of acute renal colic: a comparison of non-contrast CT versus 3-T non-contrast HASTE MR urography.

    PubMed

    Semins, M J; Feng, Z; Trock, B; Bohlman, M; Hosek, W; Matlaga, B R

    2013-02-01

    With the introduction of a 3-T scanner, magnetic resonance urography (MRU) may be an alternative imaging modality for evaluation of acute renal colic. We performed a prospective study to compare the performance of computed tomography (CT) with half-Fourier single shot turbo spin-echo (HASTE) MRU in the evaluation of patients with suspected renal colic. Patients presenting to the emergency department with acute renal colic were eligible for inclusion. Following a standard CT stone evaluation, patients underwent a non-contrast HASTE MRU study with a 3-T scanner. The presence of perinephric fluid, hydronephrosis, ureteral obstruction, and calculus was assessed. A total of 22 patients completed the study. Twenty (91 %) were diagnosed with an upper tract stone by radiographic findings. MRU detected a discrete stone in 50 % of the patients with stones detected by CT. Perinephric fluid was noted in 12 MRUs, compared to 7 CTs. Using CT as the reference standard, the combination of stone or perinephric fluid and ureteral dilation gave MRU a sensitivity of 84 %, specificity of 100 %, and accuracy of 86 % (95 % CI 0.72-1.0). HASTE MRU with a 3-T MR scanner can reliably detect the presence of upper urinary tract obstruction. Although CT imaging remains the superior modality with which to detect calculi, MRU detects a greater number of secondary signs of upper tract obstruction. For situations in which the use of ionizing radiation is undesirable, MRU is a reasonable imaging alternative.

  8. Constitutive expression of high-affinity sulfate transporter (HAST) gene in Indian mustard showed enhanced sulfur uptake and assimilation.

    PubMed

    Abdin, M Z; Akmal, M; Ram, M; Nafis, T; Alam, P; Nadeem, M; Khan, M A; Ahmad, A

    2011-07-01

    Lycopersicon esculantum sulfate transporter gene (LeST 1.1) encodes a high-affinity sulfate transporter (HAST) located in root epidermis. In this study, the LeST 1.1 gene was constitutively expressed in Indian mustard (Brassica juncea cv. Pusa Jai Kisan). Transgenic as well as untransformed plants were grown in sulfur-insufficient (25 and 50 μM) and sulfur-sufficient (1,000 μM) conditions for 30 days. Two-fold increase was noticed in the sulfate uptake rate of transgenic plants grown in both sulfur-insufficient and -sufficient conditions as compared to untransformed plants. The transgenic B. juncea plants were able to accumulate higher biomass and showed improved sulfur status even in sulfur-insufficient conditions when compared with untransformed plants. Chlorophyll content, ATP sulfurylase activity and protein content were also higher in transgenic plants than untranformed plants under sulfur-insufficient conditions. Our results, thus, clearly indicate that constitutive expression of LeST 1.1 gene in B. juncea had led to enhanced capacity of sulfur uptake and assimilation even in sulfur-insufficient conditions. This approach can also be used in other crops to enhance their sulfate uptake and assimilation potential under S-insufficient conditions.

  9. On the Metropolis-Hastings acceptance probability to add or drop a quantitative trait locus in Markov chain Monte Carlo-based Bayesian analyses.

    PubMed Central

    Jannink, Jean-Luc; Fernando, Rohan L

    2004-01-01

    The Metropolis-Hastings algorithm used in analyses that estimate the number of QTL segregating in a mapping population requires the calculation of an acceptance probability to add or drop a QTL from the model. Expressions for this acceptance probability need to recognize that sets of QTL are unordered such that the number of equivalent sets increases with the factorial of the QTL number. Here, we show how accounting for this fact affects the acceptance probability and review expressions found in the literature. PMID:15020452

  10. Fast MR Imaging of the Paediatric Abdomen with CAIPIRINHA-Accelerated T1w 3D FLASH and with High-Resolution T2w HASTE: A Study on Image Quality

    PubMed Central

    Li, Mengxia; Winkler, Beate; Pabst, Thomas; Bley, Thorsten; Köstler, Herbert; Neubauer, Henning

    2015-01-01

    The aim of this study was to explore the applicability of fast MR techniques to routine paediatric abdominopelvic MRI at 1.5 Tesla. “Controlled Aliasing in Parallel Imaging Results in Higher Acceleration-” (CAIPIRINHA-) accelerated contrast-enhanced-T1w 3D FLASH imaging was compared to standard T1w 2D FLASH imaging with breath-holding in 40 paediatric patients and to respiratory-triggered T1w TSE imaging in 10 sedated young children. In 20 nonsedated patients, we compared T2w TIRM to fat-saturated T2w HASTE imaging. Two observers performed an independent and blinded assessment of overall image quality. Acquisition time was reduced by the factor of 15 with CAIPIRINHA-accelerated T1w FLASH and by 7 with T2w HASTE. With CAIPIRINHA and with HASTE, there were significantly less motion artefacts in nonsedated patients. In sedated patients, respiratory-triggered T1w imaging in general showed better image quality. However, satisfactory image quality was achieved with CAIPIRINHA in two sedated patients where respiratory triggering failed. In summary, fast scanning with CAIPIRINHA and HASTE presents a reliable high quality alternative to standard sequences in paediatric abdominal MRI. Paediatric patients, in particular, benefit greatly from fast image acquisition with less breath-hold cycles or shorter sedation. PMID:25945088

  11. Two-dimensional direct-current resistivity survey to supplement borehole data in ground-water models of the former Blaine Naval Ammunition Depot, Hastings, Nebraska, September 2003

    USGS Publications Warehouse

    Kress, Wade H.; Ball, Lyndsay B.; Teeple, Andrew; Turco, Michael J.

    2006-01-01

    The former Blaine Naval Ammunition Depot located immediately southeast of Hastings, Nebraska, was an ammunition facility during World War II and the Korean Conflict. Waste-management practices during operation and decommissioning of the former Depot resulted in soil and ground-water contamination. Ground-water models have been used by the U.S. Army Corps of Engineers to provide information on the fate and transport of contaminants on the former Depot site. During September 2003, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, Kansas City District, conducted a pilot study to collect two-dimensional direct-current resistivity data on the site along six profiles near existing monitoring wells. The inversion results of field data from five of the six two-dimensional direct-current resistivity profiles display distinct electrical stratigraphy consistent with three resistivity units (low resistivity, high resistivity, and low resistivity). These three resistivity units correlate with rock-stratigraphic or hydrogeologic units described prior to this study. To interpret the resistivity profiles, additional data extending through the lower confining unit into the underlying Niobrara Formation could be used with the existing data to construct forward models for data analysis and interpretation.

  12. Benefits of a new Metropolis-Hasting based algorithm, in non-linear regression for estimation of ex vivo antimalarial sensitivity in patients infected with two strains.

    PubMed

    Bauer, Rebecca; Mentré, France; Kaddouri, Halima; Le Bras, Jacques; Le Nagard, Hervé

    2014-12-01

    Malaria is one of the world׳s most widespread parasitic diseases. The parasitic protozoans of the genus Plasmodium have developed resistance to several antimalarial drugs. Some patients are therefore infected by two or more strains with different levels of antimalarial drug sensitivity. We previously developed a model to estimate the drug concentration (IC50) that inhibits 50% of the growth of the parasite isolated from a patient infected with one strain. We propose here a new Two-Slopes model for patients infected by two strains. This model involves four parameters: the proportion of each strain and their IC50, and the sigmoidicity parameter. To estimate the parameters of this model, we have developed a new algorithm called PGBO (Population Genetics-Based Optimizer). It is based on the Metropolis-Hasting algorithm and is implemented in the statistical software R. We performed a simulation study and defined three evaluation criteria to evaluate its properties and compare it with three other algorithms (Gauss-Newton, Levenberg-Marquardt, and a simulated annealing). We also evaluated it using in vitro data and three ex vivo datasets from the French Malaria Reference Center. Our evaluation criteria in the simulation show that PGBO gives good estimates of the parameters even if the concentration design is poor. Moreover, our algorithm is less sensitive than Gauss-Newton algorithms to initial values. Although parameter estimation is good, interpretation of the results can be difficult if the proportion of the second strain is close to 0 or 1. For these reasons, this approach cannot yet be implemented routinely.

  13. Using satellite observations to improve model estimates of CO2 and CH4 flux: a Metropolis Hastings Markov Chain Monte Carlo approach

    NASA Astrophysics Data System (ADS)

    MacBean, Natasha; Disney, Mathias; Lewis, Philip; Ineson, Phil

    2010-05-01

    profile as a whole. We present results from an Observing System Simulation Experiment (OSSE) designed to investigate the impact of management and climate change on peatland carbon fluxes, as well as how observations from satellites may be able to constrain modeled carbon fluxes. We use an adapted version of the Carnegie-Ames-Stanford Approach (CASA) model (Potter et al., 1993) that includes a representation of methane dynamics (Potter, 1997). The model formulation is further modified to allow for assimilation of satellite observations of surface soil moisture and land surface temperature. The observations are used to update model estimates using a Metropolis Hastings Markov Chain Monte Carlo (MCMC) approach. We examine the effect of temporal frequency and precision of satellite observations with a view to establishing how, and at what level, such observations would make a significant improvement in model uncertainty. We compare this with the system characteristics of existing and future satellites. We believe this is the first attempt to assimilate surface soil moisture and land surface temperature into an ecosystem model that includes a full representation of CH4 flux. Bubier, J., and T. Moore (1994), An ecological perspective on methane emissions from northern wetlands, TREE, 9, 460-464. Charman, D. (2002), Peatlands and Environmental Change, JohnWiley and Sons, Ltd, England. Gorham, E. (1991), Northern peatlands: Role in the carbon cycle and probable responses to climatic warming, Ecological Applications, 1, 182-195. Lai, D. (2009), Methane dynamics in northern peatlands: A review, Pedosphere, 19, 409-421. Le Mer, J., and P. Roger (2001), Production, oxidation, emission and consumption of methane by soils: A review, European Journal of Soil Biology, 37, 25-50. Limpens, J., F. Berendse, J. Canadell, C. Freeman, J. Holden, N. Roulet, H. Rydin, and Potter, C. (1997), An ecosystem simulation model for methane production and emission from wetlands, Global Biogeochemical

  14. Avoid haste in defining human muscular Sarcocystosis

    USDA-ARS?s Scientific Manuscript database

    We appreciate Dr. Italiano’s [1] interest in our article [2] and agree that our case definition, described in our methods as ‘intentionally specific,’ may have resulted in the exclusion of some travelers infected with Sarcocystis nesbitti. Nevertheless, we believe published data from outbreak invest...

  15. Cases in Bioethics from the Hastings Center Report.

    ERIC Educational Resources Information Center

    Levine, Carol, Ed.; Veatch, Robert M.

    Case studies of ethical issues based on real events are followed by comments illustrating how people from various ethical traditions and frameworks and from different academic and professional disciplines analyze the issues and work toward a resolution of the conflict posed. The cases are intended to help the public and professional persons pursue…

  16. Cases in Bioethics from the Hastings Center Report.

    ERIC Educational Resources Information Center

    Levine, Carol, Ed.; Veatch, Robert M.

    Case studies of ethical issues based on real events are followed by comments illustrating how people from various ethical traditions and frameworks and from different academic and professional disciplines analyze the issues and work toward a resolution of the conflict posed. The cases are intended to help the public and professional persons pursue…

  17. Hastings Igloo Hazards Tests for Small Explosive Charges

    DTIC Science & Technology

    1984-05-01

    Continue on reverse aide // necaaaary and Identity by block number) Igloo magazines Explosive safety Fragment hazards Hazardous distances 2Q...to an exposed site when limited quantities of bulk explosives, positioned inside igloo magazines , are statically detonated. Specific test...objectives were to (1) de- termine the explosive quantity which, when detonated inside a standard-size, earth-covered magazine , produces no significant

  18. Preliminary Flight Rating Tests of the HAST Propulsion System

    DTIC Science & Technology

    1975-01-01

    project engineer for propulsion was Mr. Fred Hewitt. Contractor personnel providing support included Messrs. William Bryne , James Auiler, Gary...Management Assembly ....... 11 Controlled Thrust Assembly .......... . Z Event Sequencing ................. 24 III TES.2 FACILITY...system will reliably perform the intended flight test missions, ( Z ) verify safe altitude ignition and operation so as to be able to certify flight safety

  19. On the Uses of the Humanities: Vision and Application. A Report by the Hastings Center.

    ERIC Educational Resources Information Center

    Hastings Center, Hastings-on-Hudson, NY.

    Designed to provide a general assessment of the rapidly growing applied humanities movement in the United States, this report sets forth issues found to be central to an assessment of current work in the applied humanities, presents a general survey of the nature of applied work in a variety of disciplines, and offers conclusions and observations…

  20. The Ethics of Legislative Life. A Report by the Hastings Center.

    ERIC Educational Resources Information Center

    Hastings Center, Hastings-on-Hudson, NY.

    Results of a two-year research project (1982-84) on Legislative and Representative Ethics are presented in this report, which analyzes the basic principles of legislative ethics, discusses the special dilemmas and obligations of legislators, and offers conclusions about future steps that could be taken to enhance public discussion and to reinforce…

  1. VizieR Online Data Catalog: HST and Magellan observations of Haumea system (Hastings+, 2016)

    NASA Astrophysics Data System (ADS)

    Hastings, D. M.; Ragozzine, D.; Fabrycky, D. C.; Burkhart, L. D.; Fuentes, C.; Margot, J.-L.; Brown, M. E.; Holman, M.

    2017-01-01

    The Hubble Space Telescope (HST) observations of the Haumea system comprised five HST orbits' worth of 100s exposures of the Wide Field Planetary Camera 2 from 2009 February 4 (Program 11971) and 10 HST orbits' worth of 44s exposures of the Wide Field Camera 3 from 2010 June 28 (Program 12243). This system was also observed on the night of UT 2009 June 2 with the Magellan Baade telescope at Las Campanas Observatory in Chile. We used the Raymond and Beverly Sackler Magellan Instant Camera (MagIC). Observations were taken from the beginning of the night until it was unobservable, for a total of ~5hr. We centered the system on one of the four quadrants defined by the instrument's four amplifiers. The seeing was constant during the observations and consistently close to 0.5'', smaller than Hi'iaka's separation of 1.4''. The SITe CCD detector has a pixel scale of 0.069''/pixel. We set the exposure times at 120s to avoid saturation and optimize readout time. The filter selected was Johnson-Cousins R. Standard calibrations were taken at the beginning and end of the night. The telescope guiding system ensured that the pointing was constant to within an FWHM over the course of the observations. Table1 presents the relative normalized photometry inferred from our observations. (1 data file).

  2. More Haste, Less Speed: Could Public–Private Partnerships Advance Cellular Immunotherapies?

    PubMed Central

    Bubela, Tania; Bonter, Katherine; Lachance, Silvy; Delisle, Jean-Sébastien; Gold, E. Richard

    2017-01-01

    Cellular immunotherapies promise to transform cancer care. However, they must overcome serious challenges, including: (1) the need to identify and characterize novel cancer antigens to expand the range of therapeutic targets; (2) the need to develop strategies to minimize serious adverse events, such as cytokine release syndrome and treatment-related toxicities; and (3) the need to develop efficient production/manufacturing processes to reduce costs. Here, we discuss whether these challenges might better be addressed through forms of public–private research collaborations, including public–private partnerships (PPPs), or whether these challenges are best addressed by way of standard market transactions. We reviewed 14 public–private relationships and 25 underlying agreements for the clinical development of cancer cellular immunotherapies in the US. Most were based on bilateral research agreements and pure market transactions in the form of service contracts and technology licenses, which is representative of the commercialization focus of the field. We make the strategic case that multiparty PPPs may better advance cancer antigen discovery and characterization and improved cell processing/manufacturing and related activities. In the rush toward the competitive end of the translational continuum for cancer cellular immunotherapy and the attendant focus on commercialization, many gaps have appeared in our understanding of cellular biology, immunology, and bioengineering. We conclude that the model of bilateral agreements between leading research institutions and the private sector may be inadequate to efficiently harness the interdisciplinary skills and knowledge of the public and private sectors to bring these promising therapies to the clinic for the benefit of cancer patients. PMID:28861415

  3. [Termination of pregnancy after the 20-week ultrasonographic examination: haste and caution].

    PubMed

    van de Vathorst, S; Verhagen, A A E; Wildschut, H I J; Wolf, H; Zeeman, G G; Lind, J

    2008-11-29

    The recently introduced ultrasonographic screening programme for the detection of fetal structural anomalies at 20 weeks' gestation is leading to a growing number of cases with an unclear prognosis. This article presents the decision-making process which followed the screening of two women: one aged 36 years, where a post-screening work-up was conducted and swiftly led to well-balanced decision making to abort a fetus with trisomy 21, and one woman aged 30 years, in whom repeated non-decisive results of further diagnostic tests ultimately led to a hasty decision to abort the pregnancy. Up to 24 weeks, current Dutch law allows the couple to decide to have a termination of pregnancy; thereafter the legal possibility of having a termination is very limited. This may lead to rushed decision-making. It is argued that careful decisions in these matters are more important than staying within the 24-week limit. The national central committee ofexperts which is responsible for the evaluation of all abortions after 24 weeks gestation in the so-called category 2 cases (conditions which will lead to serious and irreparable functional disorders, such as severe spina bifida and hydrocephalus, but which are compatible with life) should take account of this dilemma ofhaste and caution.

  4. Membranes, ions, and clocks: testing the Njus-Sulzman-Hastings model of the circadian oscillator.

    PubMed

    Nitabach, Michael N; Holmes, Todd C; Blau, Justin

    2005-01-01

    Current circadian clock models based on interlocking autoregulatory transcriptional?translational negative feedback loops have arisen out of an explosion of molecular genetic data obtained over the last decade (for review, see Stanewsky, 2003; Young and Kay, 2001). An earlier model of circadian oscillation was based on feedback interactions between membrane ion transport systems and ion concentration gradients (Njus et al., 1974, 1976). This membrane model was posited as a more plausible alternative at the time to the even earlier "chronon" model, which was based on autoregulatory genetic feedback loops (Ehret and Trucco, 1967). The membrane model has been tested in a number of experimental systems by pharmacologically manipulating either ionic gradients across the plasma membrane or ion transport systems, but with inconsistent results. In the meantime, the scope and explanatory power of the genetic models overshadowed inquiries into the role of membrane ion fluxes in clock function. However, several recently developed techniques described in this article have provided a new glimpse into the essential role that membrane ion fluxes play in the mechanism of the core circadian oscillator and indicate that a complete understanding of the clock must include both genetic and membrane-based feedback loops.

  5. More Haste, Less Speed: Could Public-Private Partnerships Advance Cellular Immunotherapies?

    PubMed

    Bubela, Tania; Bonter, Katherine; Lachance, Silvy; Delisle, Jean-Sébastien; Gold, E Richard

    2017-01-01

    Cellular immunotherapies promise to transform cancer care. However, they must overcome serious challenges, including: (1) the need to identify and characterize novel cancer antigens to expand the range of therapeutic targets; (2) the need to develop strategies to minimize serious adverse events, such as cytokine release syndrome and treatment-related toxicities; and (3) the need to develop efficient production/manufacturing processes to reduce costs. Here, we discuss whether these challenges might better be addressed through forms of public-private research collaborations, including public-private partnerships (PPPs), or whether these challenges are best addressed by way of standard market transactions. We reviewed 14 public-private relationships and 25 underlying agreements for the clinical development of cancer cellular immunotherapies in the US. Most were based on bilateral research agreements and pure market transactions in the form of service contracts and technology licenses, which is representative of the commercialization focus of the field. We make the strategic case that multiparty PPPs may better advance cancer antigen discovery and characterization and improved cell processing/manufacturing and related activities. In the rush toward the competitive end of the translational continuum for cancer cellular immunotherapy and the attendant focus on commercialization, many gaps have appeared in our understanding of cellular biology, immunology, and bioengineering. We conclude that the model of bilateral agreements between leading research institutions and the private sector may be inadequate to efficiently harness the interdisciplinary skills and knowledge of the public and private sectors to bring these promising therapies to the clinic for the benefit of cancer patients.

  6. Haste makes waste: Decision making in patients with restless legs syndrome with and without augmentation

    PubMed Central

    Heim, Beatrice; Pertl, Marie-Theres; Stefani, Ambra; Delazer, Margarete; Heidbreder, Anna; Zamarian, Laura; Brandauer, Elisabeth; Seppi, Klaus; Högl, Birgit; Poewe, Werner; Djamshidian, Atbin

    2017-01-01

    Objectives To investigate decision making in patients with primary restless legs syndrome (RLS) with and without augmentation treated with dopaminergic medication. Methods A total of 64 non-demented RLS patients treated with dopaminergic medication with and without augmentation were included in this study. We used an information sampling task to assess how much evidence participants gather before making a decision. Performance was compared to the results of 21 healthy controls. Results All patients with and without augmentation gathered less information than healthy controls before making a decision (p<0.001), but there was no difference between the two patient groups (p = 1.0). Furthermore, both patient groups made more irrational decisions (e.g. decisions against the evidence they had at the time) than healthy controls (p≤0.002). In addition, RLS patients with augmentation made significantly more irrational decisions than RLS patients without augmentation (p = 0.037) and controls (p<0.001). Conclusions Our results show that RLS patients treated with dopaminergic drugs, regardless of having augmentation or not, jumped to conclusions and decided significantly more often against the evidence they had at the time of their decision. However, those with augmentation performed worse than all other groups and made more often irrational decisions, a phenomenon which is also common in patients with substance abuse or behavioural addictions. Thus, jumping to conclusions and deciding with a higher degree of uncertainty as well as irrational decision making is more common in RLS patients treated with dopaminergic medication particularly in those with augmentation. PMID:28380045

  7. Haste makes waste: Decision making in patients with restless legs syndrome with and without augmentation.

    PubMed

    Heim, Beatrice; Pertl, Marie-Theres; Stefani, Ambra; Delazer, Margarete; Heidbreder, Anna; Zamarian, Laura; Brandauer, Elisabeth; Seppi, Klaus; Högl, Birgit; Poewe, Werner; Djamshidian, Atbin

    2017-01-01

    To investigate decision making in patients with primary restless legs syndrome (RLS) with and without augmentation treated with dopaminergic medication. A total of 64 non-demented RLS patients treated with dopaminergic medication with and without augmentation were included in this study. We used an information sampling task to assess how much evidence participants gather before making a decision. Performance was compared to the results of 21 healthy controls. All patients with and without augmentation gathered less information than healthy controls before making a decision (p<0.001), but there was no difference between the two patient groups (p = 1.0). Furthermore, both patient groups made more irrational decisions (e.g. decisions against the evidence they had at the time) than healthy controls (p≤0.002). In addition, RLS patients with augmentation made significantly more irrational decisions than RLS patients without augmentation (p = 0.037) and controls (p<0.001). Our results show that RLS patients treated with dopaminergic drugs, regardless of having augmentation or not, jumped to conclusions and decided significantly more often against the evidence they had at the time of their decision. However, those with augmentation performed worse than all other groups and made more often irrational decisions, a phenomenon which is also common in patients with substance abuse or behavioural addictions. Thus, jumping to conclusions and deciding with a higher degree of uncertainty as well as irrational decision making is more common in RLS patients treated with dopaminergic medication particularly in those with augmentation.

  8. Estimation of Contextual Effects through Nonlinear Multilevel Latent Variable Modeling with a Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Yang, Ji Seung

    2012-01-01

    Nonlinear multilevel latent variable modeling has been suggested as an alternative to traditional hierarchical linear modeling to more properly handle measurement error and sampling error issues in contextual effects modeling. However, a nonlinear multilevel latent variable model requires significant computational effort because the estimation…

  9. 77 FR 35960 - City of Hastings, MN; Notice of Application for Amendment of License and Soliciting Comments...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-15

    ... delete the two hydrokinetic turbines from the Mississippi Lock and Dam No. 2 conventional hydropower... licensee proposes to amend the license to delete from the license: two hydrokinetic turbines rated at 35 kW... hydrokinetic units was deployed, and the unit has been removed and out of service since mid-2010 due to...

  10. Estimation of a Ramsay-Curve Item Response Theory Model by the Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Monroe, Scott; Cai, Li

    2014-01-01

    In Ramsay curve item response theory (RC-IRT) modeling, the shape of the latent trait distribution is estimated simultaneously with the item parameters. In its original implementation, RC-IRT is estimated via Bock and Aitkin's EM algorithm, which yields maximum marginal likelihood estimates. This method, however, does not produce the…

  11. 76 FR 15936 - Opportunity for Designation in the Aberdeen, SD; Decatur, IL; Hastings, NE; Fulton, IL; the State...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-22

    ... the North by U.S. Route 12 east to State Route 22; State Route 22 north to the Burlington-Northern (BN) line; the Burlington-Northern (BN) line east to State Route 21; State Route 21 east to State Route 49...

  12. When Does Haste Make Waste? Speed-Accuracy Tradeoff, Skill Level, and the Tools of the Trade

    ERIC Educational Resources Information Center

    Beilock, Sian L.; Bertenthal, Bennett I.; Hoerger, Michael; Carr, Thomas H.

    2008-01-01

    Novice and skilled golfers took a series of golf putts with a standard putter (Exp. 1) or a distorted "funny putter" (consisting of an s-shaped and arbitrarily weighted putter shaft; Exp. 2) under instructions to either (a) take as much time as needed to be accurate or to (b) putt as fast as possible while still being accurate. Planning and…

  13. Haste Makes Waste but Condition Matters: Molt Rate–Feather Quality Trade-Off in a Sedentary Songbird

    PubMed Central

    Vágási, Csongor I.; Pap, Péter L.; Vincze, Orsolya; Benkő, Zoltán; Marton, Attila; Barta, Zoltán

    2012-01-01

    Background The trade-off between current and residual reproductive values is central to life history theory, although the possible mechanisms underlying this trade-off are largely unknown. The ‘molt constraint’ hypothesis suggests that molt and plumage functionality are compromised by the preceding breeding event, yet this candidate mechanism remains insufficiently explored. Methodology/Principal Findings The seasonal change in photoperiod was manipulated to accelerate the molt rate. This treatment simulates the case of naturally late-breeding birds. House sparrows Passer domesticus experiencing accelerated molt developed shorter flight feathers with more fault bars and body feathers with supposedly lower insulation capacity (i.e. shorter, smaller, with a higher barbule density and fewer plumulaceous barbs). However, the wing, tail and primary feather lengths were shorter in fast-molting birds if they had an inferior body condition, which has been largely overlooked in previous studies. The rachis width of flight feathers was not affected by the treatment, but it was still condition-dependent. Conclusions/Significance This study shows that sedentary birds might face evolutionary costs because of the molt rate–feather quality conflict. This is the first study to experimentally demonstrate that (1) molt rate affects several aspects of body feathers as well as flight feathers and (2) the costly effects of rapid molt are condition-specific. We conclude that molt rate and its association with feather quality might be a major mediator of life history trade-offs. Our findings also suggest a novel advantage of early breeding, i.e. the facilitation of slower molt and the condition-dependent regulation of feather growth. PMID:22808221

  14. No haste, more taste: An EMA study of the effects of stress, negative and positive emotions on eating behavior.

    PubMed

    Reichenberger, Julia; Kuppens, Peter; Liedlgruber, Michael; Wilhelm, Frank H; Tiefengrabner, Martin; Ginzinger, Simon; Blechert, Jens

    2016-09-18

    Stress and emotions alter eating behavior in several ways: While experiencing negative or positive emotions typically leads to increased food intake, stress may result in either over- or undereating. Several participant characteristics, like gender, BMI and restrained, emotional, or external eating styles seem to influence these relationships. Thus far, most research relied on experimental laboratory studies, thereby reducing the complexity of real-life eating episodes. The aim of the present study was to delineate the effects of stress, negative and positive emotions on two key facets of eating behavior, namely taste- and hunger-based eating, in daily life using ecological momentary assessment (EMA). Furthermore, the already mentioned individual differences as well as time pressure during eating, an important but unstudied construct in EMA studies, were examined. Fifty-nine participants completed 10days of signal-contingent sampling and data were analyzed using multilevel modeling. Results revealed that higher stress led to decreased taste-eating which is in line with physiological stress-models. Time pressure during eating resulted in less taste- and more hunger-eating. In line with previous research, stronger positive emotions went along with increased taste-eating. Emotional eating style moderated the relationship between negative emotions and taste-eating as well as hunger-eating. BMI moderated the relationship between negative as well as positive emotions and hunger-eating. These findings emphasize the importance of individual differences for understanding eating behavior in daily life. Experienced time pressure may be an important aspect for future EMA eating studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. When Does Haste Make Waste? Speed-Accuracy Tradeoff, Skill Level, and the Tools of the Trade

    ERIC Educational Resources Information Center

    Beilock, Sian L.; Bertenthal, Bennett I.; Hoerger, Michael; Carr, Thomas H.

    2008-01-01

    Novice and skilled golfers took a series of golf putts with a standard putter (Exp. 1) or a distorted "funny putter" (consisting of an s-shaped and arbitrarily weighted putter shaft; Exp. 2) under instructions to either (a) take as much time as needed to be accurate or to (b) putt as fast as possible while still being accurate. Planning and…

  16. When does haste make waste? Speed-accuracy tradeoff, skill level, and the tools of the trade.

    PubMed

    Beilock, Sian L; Bertenthal, Bennett I; Hoerger, Michael; Carr, Thomas H

    2008-12-01

    Novice and skilled golfers took a series of golf putts with a standard putter (Exp. 1) or a distorted funny putter (consisting of an s-shaped and arbitrarily weighted putter shaft; Exp. 2) under instructions to either (a) take as much time as needed to be accurate or to (b) putt as fast as possible while still being accurate. Planning and movement time were measured for each putt. In both experiments, novices produced the typical speed-accuracy trade-off. Going slower, in terms of both the planning and movement components of execution, improved performance. In contrast, skilled golfers benefited from reduced performance time when using the standard putter in Exp. 1 and, specifically, taking less time to plan improved performance. In Exp. 2, skilled golfers improved by going slower when using the funny putter, but only when it was unfamiliar. Thus, skilled performance benefits from speed instructions when wielding highly familiar tools (i.e., the standard putter) is harmed when using new tools (i.e., the funny putter), and benefits again by speed instructions as the new tool becomes familiar. Planning time absorbs these changes. PsycINFO Database Record (c) 2008 APA, all rights reserved.

  17. Estimation of a Ramsay-Curve Item Response Theory Model by the Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Monroe, Scott; Cai, Li

    2014-01-01

    In Ramsay curve item response theory (RC-IRT) modeling, the shape of the latent trait distribution is estimated simultaneously with the item parameters. In its original implementation, RC-IRT is estimated via Bock and Aitkin's EM algorithm, which yields maximum marginal likelihood estimates. This method, however, does not produce the…

  18. Estimation of Contextual Effects through Nonlinear Multilevel Latent Variable Modeling with a Metropolis-Hastings Robbins-Monro Algorithm

    ERIC Educational Resources Information Center

    Yang, Ji Seung

    2012-01-01

    Nonlinear multilevel latent variable modeling has been suggested as an alternative to traditional hierarchical linear modeling to more properly handle measurement error and sampling error issues in contextual effects modeling. However, a nonlinear multilevel latent variable model requires significant computational effort because the estimation…

  19. Estimation of a Ramsay-Curve Item Response Theory Model by the Metropolis-Hastings Robbins-Monro Algorithm. CRESST Report 834

    ERIC Educational Resources Information Center

    Monroe, Scott; Cai, Li

    2013-01-01

    In Ramsay curve item response theory (RC-IRT, Woods & Thissen, 2006) modeling, the shape of the latent trait distribution is estimated simultaneously with the item parameters. In its original implementation, RC-IRT is estimated via Bock and Aitkin's (1981) EM algorithm, which yields maximum marginal likelihood estimates. This method, however,…

  20. Moral Competence for the Joint Warfighter: The Missing Element in Defense Transformation

    DTIC Science & Technology

    2006-06-01

    Gabriel 34. 49 Peter L. Stromberg, Malham M. Wakin, and Callahan, Daniel. The Teaching of Ethics in the Military, ( Hastings - on - Hudson , NY: Hastings...Stromberg, Peter L., Malham M.Wakin, and Daniel Callahan. The Teaching of Ethics in the Military, ( Hastings - on - Hudson , NY: Hastings Center, 1982

  1. An Analysis of Medical Ethic Practice by Union and Confederate Medical Departments During the American Civil War

    DTIC Science & Technology

    2011-04-05

    8217 89 Freemon, 26. 90 Michael L. Gross. /(Mapping the Moral Dimensions of Medicine and War". The Hastings Center Report. Hastings - on - Hudson : Nov...and War." The Hastings Center Report Hastings :- on - Hudson : Nov/Dec 2004. Vol. 34, Iss. 6 Humphreys, Margaret. Intensely Human, the health if the Black...inadvertently bit on the bullet end of the paper cartridge accidentally when in haste to reload his rifle. 97 Care provided by impaired providers

  2. Mississippi River 9-Foot Channel Navigation Pools, St. Anthony Falls Pools and Pools 1-10, Master Recreation Plan; Plan for Development, Lake Rebecca - Pool 2, Hastings, Minnesota. Supplement Number 1.

    DTIC Science & Technology

    1978-03-01

    environmental education programs. The northeast section of the project area has the most diversity and pro- vides the best opportunity for trail... environmental education / nature study - trails 3,000 feet - interpretive signs and materials 35 SECTION FOUR PLAN FOR DEVELOPMENT ACTIVITIES FACILITIES...zone of development the only 34 SECTION FOUR PLAN FOR DEVELOPMENT recreation facilities would be hiking, nature trails, and facilities for environmental

  3. Diversity of human astrovirus genotypes circulating in children with acute gastroenteritis in Thailand during 2000-2011.

    PubMed

    Malasao, Rungnapa; Khamrin, Pattara; Chaimongkol, Natthawan; Ushijima, Hiroshi; Maneekarn, Niwat

    2012-11-01

    Human astrovirus (HAstV) is one of the causative agents of acute gastroenteritis in children worldwide. The objective of this study was to elucidate the molecular epidemiology and genotypic diversity of HAstV circulating in pediatric patients admitted to hospital with diarrhea in Thailand during the year 2000-2011, except for 2004, 2006, and 2009. A total of 1,022 fecal specimens were tested for HAstV by reverse transcription polymerase chain reaction (RT-PCR). HAstV was detected at 1.4% (14 of 1,022). All HAstV strains detected in this study were characterized further by nucleotide sequencing and phylogenetic analysis. Analysis of 348 bp partial capsid nucleotide sequences revealed that HAstV strains detected were HAstV-1 (1a, 1b, and 1d) (8 strains), HAstV-2 (2c) (3 strains), HAstV-3 (1 strain), and HAstV-5 (2 strains). HAstV-1, the most predominant genotype was detected initially in 2002 and circulated continuously up to 2011. HAstV-2 was detected in year 2001, and 2007 and grouped into a 2c lineage. HAstV-3 was found only in 2000 and HAstV-5 was found in the year 2001. The findings indicate that a wide variety of HAstV strains continue to circulate in children admitted to hospital with acute gastroenteritis in Thailand over a decade. The data provide an epidemiological overview of HAstV infection and HAstV genotype distribution in Thailand.

  4. 78 FR 28205 - Notice of Availability of the Draft Environmental Impact Statement for the Lake Charles Carbon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-14

    ... enhanced oil recovery (EOR) operations in a portion of the West Hastings oil field in Brazoria County... confidence that the CO 2 will remain sequestered permanently in a portion in the West Hastings oil field...

  5. A Psychologist Looks at the Teaching of Ethics.

    ERIC Educational Resources Information Center

    Rest, James R.

    1982-01-01

    Proposes that college level ethics instructors and psychological researchers collaborate for the sake of improving ethics courses, evaluating programs, and advancing research. Journal available from The Hastings Center, 360 Broadway, Hastings-on-Hudson, NY 10706. (AM)

  6. Is Teaching Ethics "Making" or "Doing"?

    ERIC Educational Resources Information Center

    Goodpaster, Kenneth E.

    1982-01-01

    Examines the problems of evaluating the outcomes of college ethics courses. Three aspects of moral education which cause problems are discussed. Journal available from The Hastings Center, 360 Broadway, Hastings-on-Hudson, NY 10706. (AM)

  7. A Psychologist Looks at the Teaching of Ethics.

    ERIC Educational Resources Information Center

    Rest, James R.

    1982-01-01

    Proposes that college level ethics instructors and psychological researchers collaborate for the sake of improving ethics courses, evaluating programs, and advancing research. Journal available from The Hastings Center, 360 Broadway, Hastings-on-Hudson, NY 10706. (AM)

  8. Is Teaching Ethics "Making" or "Doing"?

    ERIC Educational Resources Information Center

    Goodpaster, Kenneth E.

    1982-01-01

    Examines the problems of evaluating the outcomes of college ethics courses. Three aspects of moral education which cause problems are discussed. Journal available from The Hastings Center, 360 Broadway, Hastings-on-Hudson, NY 10706. (AM)

  9. Results of Field and Laboratory Investigations Conducted for Remediation of Interim Response Actions, Other Contamination Sources. Volume 2. Appendixes

    DTIC Science & Technology

    1990-12-01

    of the alluvial groundwater. A.6.2 Previous Investigations Previous studies done in the Motor Pool Area include: a May 1984 RCRA audit done by the...19 HASTE STi. PFE 4/24/39 N I 6064 4/5/89 HASTE STIG. PE 4/24/189 N 6065 4/5/89 HASTE STAG. PPE 5/23/19 N 6069 4/14/89 HASTE STR. ??E 4/24/89 H 6070 4...13009 4117/69 HASTE STR6. PPE 5/1/89 K S13010 4/17/69 HVAST[ STAG. PIE 5/1/89 H 13011 4/17/10 HASTE STRG. PFE 0/4/89 Y 5/8 INCH HOSE 13012 4/17/19 HASTE

  10. Structural characterization of human aryl sulphotransferases.

    PubMed Central

    Brix, L A; Duggleby, R G; Gaedigk, A; McManus, M E

    1999-01-01

    Human aryl sulphotransferase (HAST) 1, HAST3, HAST4 and HAST4v share greater than 90% sequence identity, but vary markedly in their ability to catalyse the sulphonation of dopamine and p-nitrophenol. In order to investigate the amino acid(s) involved in determining differing substrate specificities of HASTs, a range of chimaeric HAST proteins were constructed. Analysis of chimaeric substrate specificities showed that enzyme affinities are mainly determined within the N-terminal end of each HAST protein, which includes two regions of high sequence divergence, termed Regions A (amino acids 44-107) and B (amino acids 132-164). To investigate the substrate-binding sites of HASTs further, site-directed mutagenesis was performed on HAST1 to change 13 individual residues within these two regions to the HAST3 equivalent. A single amino acid change in HAST1 (A146E) was able to change the specificity for p-nitrophenol to that of HAST3. The substrate specificity of HAST1 towards dopamine could not be converted into that of HAST3 with a single amino acid change. However, compared with wild-type HAST1, a number of the mutations resulted in interference with substrate binding, as shown by elevated Ki values towards the co-substrate 3'-phosphoadenosine 5'-phosphosulphate, and in some cases loss of activity towards dopamine. These findings suggest that a co-ordinated change of multiple amino acids in HAST proteins is needed to alter the substrate specificities of these enzymes towards dopamine, whereas a single amino acid at position 146 determines p-nitrophenol affinity. A HAST1 mutant was constructed to express a protein with four amino acids deleted (P87-P90). These amino acids were hypothesized to correspond to a loop region in close proximity to the substrate-binding pocket. Interestingly, the protein showed substrate specificities more similar to wild-type HAST3 than HAST1 and indicates an important role of these amino acids in substrate binding. PMID:9882633

  11. Complete genome sequence of human astrovirus genotype 6

    PubMed Central

    2010-01-01

    Background Human astroviruses (HAstVs) are one of the important causes of acute gastroenteritis in children. Currently, eight HAstV genotypes have been identified and all but two (HAstV-6 and HAstV-7) have been fully sequenced. We here sequenced and analyzed the complete genome of a HAstV-6 strain (192-BJ07), which was identified in Beijing, China. Results The genome of 192-BJ07 consists of 6745 nucleotides. The 192-BJ07 strain displays a 77.2-78.0% nucleotide sequence identity with other HAstV genotypes and exhibits amino acid sequence identities of 86.5-87.4%, 94.2-95.1%, and 65.5-74.8% in the ORF1a, ORF1b, and ORF2 regions, respectively. Homological analysis of ORF2 shows that 192-BJ07 is 96.3% identical to the documented HAstV-6 strain. Further, phylogenetic analysis indicates that different genomic regions are likely undergoing different evolutionary and selective pressures. No recombination event was observed in HAstV-6 in this study. Conclusion The completely sequenced and characterized genome of HAstV-6 (192-BJ07) provides further insight into the genetics of astroviruses and aids in the surveillance and control of HAstV gastroenteritis. PMID:20137100

  12. Structure of a Human Astrovirus Capsid-Antibody Complex and Mechanistic Insights into Virus Neutralization

    SciTech Connect

    Bogdanoff, Walter A.; Campos, Jocelyn; Perez, Edmundo I.; Yin, Lu; Alexander, David L.; DuBois, Rebecca M.; López, Susana

    2016-11-02

    ABSTRACT

    Human astroviruses (HAstVs) are a leading cause of viral diarrhea in young children, the immunocompromised, and the elderly. There are no vaccines or antiviral therapies against HAstV disease. Several lines of evidence point to the presence of protective antibodies in healthy adults as a mechanism governing protection against reinfection by HAstV. However, development of anti-HAstV therapies is hampered by the gap in knowledge of protective antibody epitopes on the HAstV capsid surface. Here, we report the structure of the HAstV capsid spike domain bound to the neutralizing monoclonal antibody PL-2. The antibody uses all six complementarity-determining regions to bind to a quaternary epitope on each side of the dimeric capsid spike. We provide evidence that the HAstV capsid spike is a receptor-binding domain and that the antibody neutralizes HAstV by blocking virus attachment to cells. We identify patches of conserved amino acids that overlap the antibody epitope and may comprise a receptor-binding site. Our studies provide a foundation for the development of therapies to prevent and treat HAstV diarrheal disease.

    IMPORTANCEHuman astroviruses (HAstVs) infect nearly every person in the world during childhood and cause diarrhea, vomiting, and fever. Despite the prevalence of this virus, little is known about how antibodies in healthy adults protect them against reinfection. Here, we determined the crystal structure of a complex of the HAstV capsid protein and a virus-neutralizing antibody. We show that the antibody binds to the outermost spike domain of the capsid, and we provide evidence that the antibody blocks virus attachment to human cells. Importantly, our findings suggest that a subunit-based vaccine focusing the immune system on the HAstV capsid spike domain could be effective in protecting children against HAstV disease.

  13. Structural, Mechanistic, and Antigenic Characterization of the Human Astrovirus Capsid

    PubMed Central

    York, Royce L.; Yousefi, Payam A.; Bogdanoff, Walter; Haile, Sara; Tripathi, Sarvind

    2015-01-01

    ABSTRACT Human astroviruses (HAstVs) are nonenveloped, positive-sense, single-stranded RNA viruses that are a leading cause of viral gastroenteritis. HAstV particles display T=3 icosahedral symmetry formed by 180 copies of the capsid protein (CP), which undergoes proteolytic maturation to generate infectious HAstV particles. Little is known about the molecular features that govern HAstV particle assembly, maturation, infectivity, and immunogenicity. Here we report the crystal structures of the two main structural domains of the HAstV CP: the core domain at 2.60-Å resolution and the spike domain at 0.95-Å resolution. Fitting of these structures into the previously determined 25-Å-resolution electron cryomicroscopy density maps of HAstV allowed us to characterize the molecular features on the surfaces of immature and mature T=3 HAstV particles. The highly electropositive inner surface of HAstV supports a model in which interaction of the HAstV CP core with viral RNA is a driving force in T=3 HAstV particle formation. Additionally, mapping of conserved residues onto the HAstV CP core and spike domains in the context of the immature and mature HAstV particles revealed dramatic changes to the exposure of conserved residues during virus maturation. Indeed, we show that antibodies raised against mature HAstV have reactivity to both the HAstV CP core and spike domains, revealing for the first time that the CP core domain is antigenic. Together, these data provide new molecular insights into HAstV that have practical applications for the development of vaccines and antiviral therapies. IMPORTANCE Astroviruses are a leading cause of viral diarrhea in young children, immunocompromised individuals, and the elderly. Despite the prevalence of astroviruses, little is known at the molecular level about how the astrovirus particle assembles and is converted into an infectious, mature virus. In this paper, we describe the high-resolution structures of the two main astrovirus

  14. 76 FR 69613 - Special Local Regulations and Safety Zones; Recurring Events in Captain of the Port New York Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... from the barge. 5.6 Hastings-on-Hudson, Hudson River Launch site: A barge Safety Zone. located in approximate position 40 59'44.5'' N 073 53'28'' W (NAD 1983), approximately 425 yards west of Hastings-on-Hudson, New York. This Safety Zone is a 360-yard radius from the barge. 5.7 Pier D, Hudson River...

  15. 1. Photocopied October 1976, from F.B. Tower, Illistrations of the ...

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

    1. Photocopied October 1976, from F.B. Tower, Illistrations of the Croton Aqueduct, New York: Wiley and Putnam, 1843. CROTON AQUEDUCT AT HASTINGS: ARCH PROVIDED ACCESS TO STONE QUARRY. PLATE XVII, PAGE 106. - Old Croton Aqueduct, Quarry Railroad Bridge, Aqueduct Lane at Williams Street, Hastings-on-Hudson, Westchester County, NY

  16. Alternative Program in Small School Stays in the Mainstream.

    ERIC Educational Resources Information Center

    Fazio, Thomas J.; Rossi, Michael J.

    1991-01-01

    The Hastings Alternative School Program (HASP), designed for at-risk students, operates within Hastings-on-Hudson (New York) High School's regular program. Students are given an external structure and set of expectations enforced by an accountability system stressing communication and student responsibility. Nearly half of all HASP students go on…

  17. Professional Military Ethics Education and Core Character Values in the Joint Profession of Arms

    DTIC Science & Technology

    1998-01-01

    Military ( Hastings - on - Hudson , NY: Institute of Society, Ethics and the Life Sciences, 1982), 19. CHAPTER 6 CONCLUSION Higher...Stromberg, Peter L., Malham M. Wakin and Daniel Callahan. The Teaching of Ethics in the Military. Hastings - on - Hudson , New York: Institute of Society

  18. Wisdom from the Factory Floor: For Best Results, Limit Initiatives, Build Capacity, and Monitor Progress

    ERIC Educational Resources Information Center

    Dumas, Chad; Kautz, Craig

    2014-01-01

    In the Hastings Nebraska Public schools, two of the eight schools have been identified as national models of educational effectiveness. In seven of eight buildings, in just four years, student test scores have increased from around 60% proficiency to around 80% proficiency or better. At Hastings, central office leaders emphasize three key…

  19. Wisdom from the Factory Floor: For Best Results, Limit Initiatives, Build Capacity, and Monitor Progress

    ERIC Educational Resources Information Center

    Dumas, Chad; Kautz, Craig

    2014-01-01

    In the Hastings Nebraska Public schools, two of the eight schools have been identified as national models of educational effectiveness. In seven of eight buildings, in just four years, student test scores have increased from around 60% proficiency to around 80% proficiency or better. At Hastings, central office leaders emphasize three key…

  20. 75 FR 76778 - Environmental Impact Statement for the Milwaukee, WI (Milwaukee Intermodal Station) to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-09

    ... Canadian Pacific Railway (CP) right-of-way from Milwaukee, WI to Watertown, WI; right-of-way owned by the... Madison, WI; CP right-of-way from Johnson Street Yard in Madison through Portage, WI and La Crosse, WI to Red Wing, MN and to Hastings, MN; CP or BNSF Railway Co. (BNSF) right-of-way from Hastings, MN to St...

  1. Surveillance of Human Astrovirus Infection in Brazil: The First Report of MLB1 Astrovirus

    PubMed Central

    Xavier, Maria da Penha Trindade Pinheiro; Carvalho Costa, Filipe Aníbal; Rocha, Mônica Simões; de Andrade, Juliana da Silva Ribeiro; Diniz, Fernanda Kreischer Bandeira; de Andrade, Thais Ramos; Miagostovich, Marize Pereira; Leite, José Paulo Gagliardi; Volotão, Eduardo de Mello

    2015-01-01

    Human astrovirus (HAstV) represents the third most common virus associated with acute diarrhea (AD). This study aimed to estimate the prevalence of HAstV infection in Brazilian children under 5 years of age with AD, investigate the presence of recently described HAstV strains, through extensive laboratory-based surveillance of enteric viral agents in three Brazilian coastal regions between 2005 and 2011. Using reverse transcription-polymerase chain reaction (RT-PCR), the overall HAstV detection rate reached 7.1% (207/2.913) with percentage varying according to the geographic region: 3.9% (36/921) in the northeast, 7.9% in the south (71/903) and 9.2% in the southeast (100/1.089) (p < 0.001). HAstV were detected in cases of all age groups. Detection rates were slightly higher during the spring. Nucleotide sequence analysis of a 320-bp ORF2 fragment revealed that HAstV-1 was the predominant genotype throughout the seven years of the study. The novel AstV-MLB1 was detected in two children with AD from a subset of 200 samples tested, demonstrating the circulation of this virus both the in northeastern and southeastern regions of Brazil. These results provide additional epidemiological and molecular data on HAstV circulation in three Brazilian coastal regions, highlighting its potential to cause infantile AD. PMID:26274322

  2. A Comparison of Estimation Methods for a Multi-unidimensional Graded Response IRT Model

    PubMed Central

    Kuo, Tzu-Chun; Sheng, Yanyan

    2016-01-01

    This study compared several parameter estimation methods for multi-unidimensional graded response models using their corresponding statistical software programs and packages. Specifically, we compared two marginal maximum likelihood (MML) approaches (Bock-Aitkin expectation-maximum algorithm, adaptive quadrature approach), four fully Bayesian algorithms (Gibbs sampling, Metropolis-Hastings, Hastings-within-Gibbs, blocked Metropolis), and the Metropolis-Hastings Robbins-Monro (MHRM) algorithm via the use of IRTPRO, BMIRT, and MATLAB. Simulation results suggested that, when the intertrait correlation was low, these estimation methods provided similar results. However, if the dimensions were moderately or highly correlated, Hastings-within-Gibbs had an overall better parameter recovery of item discrimination and intertrait correlation parameters. The performances of these estimation methods with different sample sizes and test lengths are also discussed. PMID:27375545

  3. 3. Historic American Buildings Survey California State Library Collection Sacramento ...

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

    3. Historic American Buildings Survey California State Library Collection Sacramento Co. History Thompson & West Sketch of 1880 Rephoto 1960 NORTHEAST CORNER - B. F. Hastings Bank Building, 128-132 J Street, Sacramento, Sacramento County, CA

  4. 16. Photocopy of postcard (from Ardella Fish Shanks) Frank Stumm, ...

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

    16. Photocopy of postcard (from Ardella Fish Shanks) Frank Stumm, photographer ca. 1908-16 SOUTH FRONT, HASTINGS HOUSE IN BACKGROUND - Riddell Fish House, 245 West K Street, Benicia, Solano County, CA

  5. Organ Transplantation

    MedlinePlus

    ... Health Care Science and the Self Humans and Nature Publications & Resources Back Hastings Center Report Special Reports ... Health Care Science and the Self Humans and Nature Public Events List of all our Public Events ...

  6. Geoscientists for international development

    USGS Publications Warehouse

    Hastings, David A.

    1980-01-01

    Professional societies are usually concerned with the advancement of scientific knowledge, but a relative newcomer to the international scene has a different focus - geoscience development in the Third World. David Hastings, a member of AGID, explains.

  7. 24. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR ...

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

    24. BUILDING NO. 266, GENERAL PURPOSE LABORATORY (ORIGINALLY MAGAZINE FOR HE 'A' PUMP & CHANGE HOUSE), LOOKING HAST AT NORTHWEST SIDE OF BUILDING. - Picatinny Arsenal, 200 Area, Shell Component Loading, State Route 15 near I-80, Dover, Morris County, NJ

  8. Plastic encapsulated parts

    SciTech Connect

    Castillo, T.

    1994-10-01

    Plastic semiconductor packages were characterized as possible alternatives for canned devices, which are susceptible to internal shorts caused by conductive particles. Highly accelerated stress testing (HAST) as well as electrical and mechanical testing were conducted on plastic technology devices.

  9. PTB Binds to the 3’ Untranslated Region of the Human Astrovirus Type 8: A Possible Role in Viral Replication

    PubMed Central

    Espinosa-Hernández, Wendy; Velez-Uriza, Dora; Valdés, Jesús; Vélez-Del Valle, Cristina; Salas-Benito, Juan; Martínez-Contreras, Rebeca; García-Espítia, Matilde; Salas-Benito, Mariana; Vega-Almeida, Tania; De Nova-Ocampo, Mónica

    2014-01-01

    The 3′ untranslated region (3′UTR) of human astroviruses (HAstV) consists of two hairpin structures (helix I and II) joined by a linker harboring a conserved PTB/hnRNP1 binding site. The identification and characterization of cellular proteins that interact with the 3′UTR of HAstV-8 virus will help to uncover cellular requirements for viral functions. To this end, mobility shift assays and UV cross-linking were performed with uninfected and HAstV-8-infected cell extracts and HAstV-8 3′UTR probes. Two RNA-protein complexes (CI and CII) were recruited into the 3′UTR. Complex CII formation was compromised with cold homologous RNA, and seven proteins of 35, 40, 45, 50, 52, 57/60 and 75 kDa were cross-linked to the 3′UTR. Supermobility shift assays indicated that PTB/hnRNP1 is part of this complex, and 3′UTR-crosslinked PTB/hnRNP1 was immunoprecipitated from HAstV-8 infected cell-membrane extracts. Also, immunofluorescence analyses revealed that PTB/hnRNP1 is distributed in the nucleus and cytoplasm of uninfected cells, but it is mainly localized perinuclearly in the cytoplasm of HAstV-8 infected cells. Furthermore, the minimal 3′UTR sequences recognized by recombinant PTB are those conforming helix I, and an intact PTB/hnRNP1-binding site. Finally, small interfering RNA-mediated PTB/hnRNP1 silencing reduced synthesis viral genome and virus yield in CaCo2 cells, suggesting that PTB/hnRNP1 is required for HAstV replication. In conclusion, PTB/hnRNP1 binds to the 3′UTR HAstV-8 and is required or participates in viral replication. PMID:25406089

  10. Epidemiology and genetic diversity of classic human astrovirus among hospitalized children with acute gastroenteritis in Uruguay.

    PubMed

    Lopez, Fernando; Lizasoain, Andrés; Victoria, Matías; Papalardo, Cecilia; Castro, Sebastian; Arreseigor, Edit; López, Patricia; Colina, Rodney

    2017-10-01

    Classic Human Astrovirus (Classic HAstV) are one of the most important causes of pediatric acute gastroenteritis (AGE), after rotaviruses and arguably caliciviruses. The aim of this study was to determine the molecular epidemiology of Classic HAstV from 175 clinical samples, being 153 stools and 22 vomits, collected from pediatric hospitalized patients with AGE in Salto city, Uruguay, from January 2011 to December 2012. Classic HAstV were detected and genotyped by using a qualitative Retro Transcription-Polimerase Chain Reaction (RT-PCR) directed to the Open Reading Frame-2 (ORF2) region C. Amplicons were sequenced and phylogenetic analyses were carried out in order to determine genotypes and lineages. Classic HAstV were detected in 18 out of 175 analyzed samples (10.3%) and 14 of them (78.0%) were successfully sequenced being 6 (42.8%) classified as HAstV-1 (1a lineage), 4 (28.6%) as HAstV-2 (2c lineage), and 4 (28.6%) as HAstV-3 (3c lineage). A higher detection of Classic HAstV infections was observed in autumn for both years of surveillance, and the majority of the positive cases were observed in 2011. The group of children between 2 and 5 years old presented the higher percentage of infections. To our knowledge, the present study represents the first report of astrovirus from acute gastroenteritis cases in Uruguay, evidencing its role as a relevant etiologic agent in severe cases of this disease. © 2017 Wiley Periodicals, Inc.

  11. PTB binds to the 3' untranslated region of the human astrovirus type 8: a possible role in viral replication.

    PubMed

    Espinosa-Hernández, Wendy; Velez-Uriza, Dora; Valdés, Jesús; Vélez-Del Valle, Cristina; Salas-Benito, Juan; Martínez-Contreras, Rebeca; García-Espítia, Matilde; Salas-Benito, Mariana; Vega-Almeida, Tania; De Nova-Ocampo, Mónica

    2014-01-01

    The 3' untranslated region (3'UTR) of human astroviruses (HAstV) consists of two hairpin structures (helix I and II) joined by a linker harboring a conserved PTB/hnRNP1 binding site. The identification and characterization of cellular proteins that interact with the 3'UTR of HAstV-8 virus will help to uncover cellular requirements for viral functions. To this end, mobility shift assays and UV cross-linking were performed with uninfected and HAstV-8-infected cell extracts and HAstV-8 3'UTR probes. Two RNA-protein complexes (CI and CII) were recruited into the 3'UTR. Complex CII formation was compromised with cold homologous RNA, and seven proteins of 35, 40, 45, 50, 52, 57/60 and 75 kDa were cross-linked to the 3'UTR. Supermobility shift assays indicated that PTB/hnRNP1 is part of this complex, and 3'UTR-crosslinked PTB/hnRNP1 was immunoprecipitated from HAstV-8 infected cell-membrane extracts. Also, immunofluorescence analyses revealed that PTB/hnRNP1 is distributed in the nucleus and cytoplasm of uninfected cells, but it is mainly localized perinuclearly in the cytoplasm of HAstV-8 infected cells. Furthermore, the minimal 3'UTR sequences recognized by recombinant PTB are those conforming helix I, and an intact PTB/hnRNP1-binding site. Finally, small interfering RNA-mediated PTB/hnRNP1 silencing reduced synthesis viral genome and virus yield in CaCo2 cells, suggesting that PTB/hnRNP1 is required for HAstV replication. In conclusion, PTB/hnRNP1 binds to the 3'UTR HAstV-8 and is required or participates in viral replication.

  12. Window of Opportunity: Mitigating Threats from Disruptive Technologies Before Widespread Adoption

    DTIC Science & Technology

    2014-09-01

    for a technology’s future diffusion and adoption. 5 II. UNDERSTANDING THE THREAT In our haste to milk technology for immediate economic...selfishly. In our haste to milk technology for immediate economic advantage, we have turned our environment into a physical and social tinderbox. Our...further development of the technology. The innovation process is fluid in nature, which means that it is not possible or even useful to try and

  13. Complete genome sequencing of a recombinant strain between human astrovirus antigen types 2 and 8 isolated from South Korea.

    PubMed

    Ha, Hyun-Ju; Lee, Sung-Geun; Cho, Han-Gil; Jin, Ji-Young; Lee, Jae Woong; Paik, Soon-Yong

    2016-04-01

    Human astroviruses (HAstVs) occur worldwide and are known to the causative agents of diarrhea in infants and elderly patients with immune dysfunction. This study aimed to identify recombinant HAstV strains and characterize rare genotypes. The full-length genome of a recombinant HAstV strain isolated from the stool sample of a patient with acute gastroenteritis from South Korea was amplified using three pairs of previously designed primers and seven newly designed primers. The recombinant HAstV was 6757-bp long and contained three sequential open reading frames (ORFs), designated as ORF1a (2781 bp), ORF1b (1548 bp), and ORF2 (2349 bp). Our findings suggested that a recombination event had occurred between ORF1b and ORF2 of the isolated strain, with a recombination breakpoint at 4081 bp. To our knowledge, this is the first study to reveal the complete nucleotide sequence of a recombinant HAstV strain from South Korea. Our study findings might be useful for identifying other recombinant HAstV strains and for developing vaccines against this pathogenic virus. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Prevalence and Genetic Diversity of Human Astroviruses in Mexican Children with Symptomatic and Asymptomatic Infections

    PubMed Central

    Méndez-Toss, Martha; Griffin, Dixie D.; Calva, Juan; Contreras, Juan F.; Puerto, Fernando I.; Mota, Felipe; Guiscafré, Héctor; Cedillo, Roberto; Muñoz, Onofre; Herrera, Ismael; López, Susana; Arias, Carlos F.

    2004-01-01

    The prevalence and type diversity of human astroviruses (HAstV) in children with symptomatic and asymptomatic infections were determined in five localities of Mexico. HAstV were detected in 4.6 (24 of 522) and 2.6% (11 of 428) of children with and without diarrhea, respectively. Genotyping of the detected strains showed that at least seven (types 1 to 4 and 6 to 8) of the eight known HAstV types circulated in Mexico between October 1994 and March 1995. HAstV types 1 and 3 were the most prevalent in children with diarrhea, although they were not found in all localities studied. HAstV type 8 was found in Mexico City, Monterrey, and Mérida; in the last it was as prevalent (40%) as type 1 viruses, indicating that this astrovirus type is more common than previously recognized. A correlation between the HAstV infecting type and the presence or absence of diarrheic symptoms was not observed. Enteric adenoviruses were also studied, and they were found to be present in 2.3 (12 of 522) and 1.4% (6 of 428) of symptomatic and asymptomatic children, respectively. PMID:14715746

  15. Epidemiological Characteristics of Sapovirus and Human Astrovirus Detected among Children in Nara Prefecture, Japan, during the 2009/2010-2014/2015 Seasons.

    PubMed

    Yoneda, Masaki; Nakano, Mamoru; Sugimoto, Daichi; Inada, Machi; Fujitani, Misako; Kitahori, Yoshiteru

    2017-01-24

    The current study elucidated the epidemiological characteristics of sapovirus (SaV) and human astrovirus (HAstV) associated with gastroenteritis among children in regional populations of Nara Prefecture, Japan, during the 2009/2010-2014/2015 seasons. The SaV detection rate was 7.5% (71/948) according to reverse transcription-polymerase chain reaction. A high SaV detection rate of 13.5% was observed among children 4 years of age. The highest SaV detection rate was observed in June (19.2%), followed by July (11.1%). The detected SaV included 7 genotypes: GI.1, GI.2, GII.3, GII.1, GI.3, GII.2, and GV, in order of decreasing prevalence. In comparison, the HAstV detection rate was 4.2% (40/948). The HAstV detection rate among children 4 years of age was 12.2%. The HAstV detection rate was highest in July (13.9%), followed by May (10.5%) and August (6.7%). The detected HAstVs included genotypes 1, 4, 6, and 8. The most prevalent genotype was 1, followed by 4 and 8. This report provides an epidemiological overview of SaV and HAstV infection in Nara Prefecture, Japan.

  16. Human Astroviruses

    PubMed Central

    Pintó, Rosa M.; Guix, Susana

    2014-01-01

    SUMMARY Human astroviruses (HAtVs) are positive-sense single-stranded RNA viruses that were discovered in 1975. Astroviruses infecting other species, particularly mammalian and avian, were identified and classified into the genera Mamastrovirus and Avastrovirus. Through next-generation sequencing, many new astroviruses infecting different species, including humans, have been described, and the Astroviridae family shows a high diversity and zoonotic potential. Three divergent groups of HAstVs are recognized: the classic (MAstV 1), HAstV-MLB (MAstV 6), and HAstV-VA/HMO (MAstV 8 and MAstV 9) groups. Classic HAstVs contain 8 serotypes and account for 2 to 9% of all acute nonbacterial gastroenteritis in children worldwide. Infections are usually self-limiting but can also spread systemically and cause severe infections in immunocompromised patients. The other groups have also been identified in children with gastroenteritis, but extraintestinal pathologies have been suggested for them as well. Classic HAstVs may be grown in cells, allowing the study of their cell cycle, which is similar to that of caliciviruses. The continuous emergence of new astroviruses with a potential zoonotic transmission highlights the need to gain insights on their biology in order to prevent future health threats. This review focuses on the basic virology, pathogenesis, host response, epidemiology, diagnostic assays, and prevention strategies for HAstVs. PMID:25278582

  17. Genetic heterogeneity and recombination in type-3 human astroviruses.

    PubMed

    Medici, Maria Cristina; Tummolo, Fabio; Martella, Vito; Banyai, Krisztián; Bonerba, Elisabetta; Chezzi, Carlo; Arcangeletti, Maria Cristina; De Conto, Flora; Calderaro, Adriana

    2015-06-01

    Human astroviruses (HAstVs) are important enteric pathogens and can be classified genetically and antigenically into eight types. During molecular surveillance for HAstVs in Italy, sequence analysis of the diagnostic region C (about 400 nucleotide in length), located on the capsid (ORF2) gene, identified a novel type-3 strain. Upon sequencing of the full-length ORF2, the type-3 HAstV strain was characterized as a novel ORF2 genetic lineage, designated as 3c. By converse, in the ORF1b the virus was more similar to type-1 HAstVs, rather than to type-3 strains, suggesting a recombination nature, with the crossover site being mapped to the ORF1b/ORF2 junction region. Region C sequences of similar type-3 HAstV identified from European and extra-European countries were retrieved in the databases, suggesting the global distribution of this novel type-3 lineage. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Examination of a plasmid-based reverse genetics system for human astrovirus.

    PubMed

    Chapellier, Benoit; Tange, Shoichiro; Tasaki, Hidetaka; Yoshida, Kazuhiro; Zhou, Yan; Sakon, Naomi; Katayama, Kazuhiko; Nakanishi, Akira

    2015-10-01

    A plasmid-based reverse genetics system for human astrovirus type 1 (HAstV1) is examined. Upon transfection into 293T cells, the plasmid vector, which harbors a HAstV1 expression cassette, expressed astroviral RNA that appeared to be capable of viral RNA replication, as indicated by the production of subgenomic RNA and capsid protein expression irrespective of the heterologous 5' ends of the transcribed RNA. Particles infectious to Caco-2 cells were made in this system; however, their infectivity was much lower than would be expected from the amount of particles apparently produced. Using Huh-7 cells as the transfection host with the aim of improving viral capsid processing for virion maturation partially restored the efficiency of infectious particle formation. Our results support the possibility that the DNA transfection process induces a cellular response that targets late, but not early, stages of HAstV1 infection.

  19. Research Studies on Photons and Biphotons

    DTIC Science & Technology

    2013-10-01

    Ultrabright Backward Wave Biphoton Source”, Phys. Rev. A, 83, 061803R, 2011. (5) S. Shwartz, R.N. Coffee , J.M. Feldkamp, Y. Feng, J.B. Hastings, G.Y...E. Glover, D. M. Fritz, M. Cammarata, T. K. Allison, Sinisa Coh, J. M. Feldkamp, H. Lemke, D. Zhu, Y. Feng, R. N. Coffee , M. Fuchs, S. Ghimire, J...LCLS/SSRL users’ meeting SLAC, CA (2011) (Invited). (9) S. Shwartz, R. N. Coffee , J. M. Feldkamp, Y. Feng, J. B. Hastings, G. Y. Yin, and S. E

  20. Energetic Oxetane Thermoplastic Elastomer Binders

    DTIC Science & Technology

    1992-12-01

    Naval Air Warfare Center personnel on the project was particularly helpful. We recognize the contributions of Geoff Lindsay, Mostafa Talukder , Mel... Talukder , M.A.H.; Nissan, R.A.; Quintana, R.L; Hasting, M.A.S.; Yee, R.Y.; D-7 Nadler, M.P.; Atwood, A.I.; Reed, R.; Manser, G.E. "Energetic Polyoxetane...G.A.; Talukder , M.A.H.; Nissan, R.A.; Quintana, R.L; Hasting, M.A.S.; Yee, R.Y.; Nadler, M.P.; Atwood, A.I.; Reed, R.; Manser, G.E. "Energetic

  1. Crystal Structure of the Human Astrovirus Capsid Protein

    PubMed Central

    Toh, Yukimatsu; Harper, Justin; Dryden, Kelly A.; Yeager, Mark; Méndez, Ernesto

    2016-01-01

    ABSTRACT Human astrovirus (HAstV) is a leading cause of viral diarrhea in infants and young children worldwide. HAstV is a nonenveloped virus with a T=3 capsid and a positive-sense RNA genome. The capsid protein (CP) of HAstV is synthesized as a 90-kDa precursor (VP90) that can be divided into three linear domains: a conserved N-terminal domain, a hypervariable domain, and an acidic C-terminal domain. Maturation of HAstV requires proteolytic processing of the astrovirus CP both inside and outside the host cell, resulting in the removal of the C-terminal domain and the breakdown of the rest of the CP into three predominant protein species with molecular masses of ∼34, 27/29, and 25/26 kDa, respectively. We have now solved the crystal structure of VP9071–415 (amino acids [aa] 71 to 415 of VP90) of human astrovirus serotype 8 at a 2.15-Å resolution. VP9071–415 encompasses the conserved N-terminal domain of VP90 but lacks the hypervariable domain, which forms the capsid surface spikes. The structure of VP9071–415 is comprised of two domains: an S domain, which adopts the typical jelly-roll β-barrel fold, and a P1 domain, which forms a squashed β-barrel consisting of six antiparallel β-strands similar to what was observed in the hepatitis E virus (HEV) capsid structure. Fitting of the VP9071–415 structure into the cryo-electron microscopy (EM) maps of HAstV produced an atomic model for a continuous, T=3 icosahedral capsid shell. Our pseudoatomic model of the human HAstV capsid shell provides valuable insights into intermolecular interactions required for capsid assembly and trypsin-mediated proteolytic maturation needed for virus infectivity. Such information has potential applications in the development of a virus-like particle (VLP) vaccine as well as small-molecule drugs targeting astrovirus assembly/maturation. IMPORTANCE Human astrovirus (HAstV) is a leading cause of viral diarrhea in infants and young children worldwide. As a nonenveloped virus

  2. Moderate Baseline Vagal Tone Predicts Greater Prosociality in Children

    ERIC Educational Resources Information Center

    Miller, Jonas G.; Kahle, Sarah; Hastings, Paul D.

    2017-01-01

    Vagal tone is widely believed to be an important physiological aspect of emotion regulation and associated positive behaviors. However, there is inconsistent evidence for relations between children's baseline vagal tone and their helpful or prosocial responses to others (Hastings & Miller, 2014). Recent work in adults suggests a quadratic…

  3. 75 FR 65282 - Medicare and Medicaid Programs; Requirements for Long Term Care Facilities; Hospice Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... skilled nursing facility (SNF) in the Medicare program, or as a nursing facility (NF) in the Medicaid..., approximately 1.4 million elderly and disabled nursing home residents are receiving care in nearly 16,000... percent of older Americans die in nursing homes. (Johnson, Sandra H., Hastings Center Report, Making Room...

  4. Statistical Modeling Efforts for Headspace Gas

    SciTech Connect

    Weaver, Brian Phillip

    2016-03-17

    The purpose of this document is to describe the statistical modeling effort for gas concentrations in WIPP storage containers. The concentration (in ppm) of CO2 in the headspace volume of standard waste box (SWB) 68685 is shown. A Bayesian approach and an adaptive Metropolis-Hastings algorithm were used.

  5. PROTECTIVE VALUE OF TYPHOID VACCINATION AS SHOWN BY THE EXPERIENCE OF THE AMERICAN TROOPS IN THE WAR

    PubMed Central

    Soper, George A.

    1920-01-01

    It has recently been publicly argued that the Army reports demonstrate the failure of inoculation against typhoid fever. Major Soper distinctly contradicts this claim, states plainly how efficient it really was and explains some so-called failures. These were due to infection before vaccination, errors of haste in insufficient dosage or wrong counting, or worn immunity. PMID:18010282

  6. "(Un)informed College and Major Choice": Verification in an Alternate Setting. CEDR Working Paper. WP #2015-11

    ERIC Educational Resources Information Center

    Huntington-Klein, Nick

    2015-01-01

    The decision to pursue formal education has significant labor market implications. To approach the decision rationally, a student must consider the costs and benefits of each available option. However, mounting empirical evidence suggests that reported expectations of costs and benefits are uncertain and vary across students. Hastings et al.…

  7. Summary of Higher Education Accountability Statutes in Other States. OP/04-04

    ERIC Educational Resources Information Center

    California Postsecondary Education Commission, 2004

    2004-01-01

    The Public Law Research Institute at the University of California Hastings College of the Law, with whom the California Postsecondary Education Commission (CPEC) forged a partnership to research, analyze, and make sound recommendations regarding an accountability structure, provides an excellent opportunity for CPEC regarding federal and state…

  8. 33 CFR 165.160 - Safety Zones; fireworks displays and swim events in Coast Guard Captain of the Port New York Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...″ W (NAD 1983), approximately 425 yards west of Hastings-on-Hudson, New York. This Safety Zone is a... maintain a separation of at least 100 yards from the participants. Table 1 to § 165.160 1.0 Hudson River 1.... • Location: All waters of the Hudson River bounded by a line drawn east from approximate position...

  9. 33 CFR 165.160 - Safety Zones; fireworks displays and swim events in Coast Guard Captain of the Port New York Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...″ W (NAD 1983), approximately 425 yards west of Hastings-on-Hudson, New York. This Safety Zone is a... maintain a separation of at least 100 yards from the participants. Table 1 to § 165.160 1.0 Hudson River 1.... • Location: All waters of the Hudson River bounded by a line drawn east from approximate position...

  10. 33 CFR 165.160 - Safety Zones; fireworks displays and swim events in Coast Guard Captain of the Port New York Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...″ W (NAD 1983), approximately 425 yards west of Hastings-on-Hudson, New York. This Safety Zone is a... maintain a separation of at least 100 yards from the participants. Table 1 to § 165.160 1.0 Hudson River 1.... • Location: All waters of the Hudson River bounded by a line drawn east from approximate position...

  11. LEACHING BOUNDARY IN CEMENT-BASED WASTE FORMS

    EPA Science Inventory

    Cement-based fixation systems are among the most commonly employed stabilization/solidification techniques. These cement haste mixtures, however, are vulnerable to ardic leaching solutions. Leaching of cement-based waste forms in acetic acid solutions with different acidic streng...

  12. Algorithm for the Retrieval of Fire Pixels from DMSP Operational Linescan System Data

    DTIC Science & Technology

    1995-06-29

    near Darjeeling , India in May 1848, British naturalist Joseph Dalton Hooker (1855) wrote that "fires, invisible by day, are seen raging all around...Washington, D.C, Final Report Volume II. Hooker , J.D., 1855: "Himalayan Journals" John Murray, London. 22 Row, L.W. Ill and Hastings, D.A., 1995

  13. Moderate Baseline Vagal Tone Predicts Greater Prosociality in Children

    ERIC Educational Resources Information Center

    Miller, Jonas G.; Kahle, Sarah; Hastings, Paul D.

    2017-01-01

    Vagal tone is widely believed to be an important physiological aspect of emotion regulation and associated positive behaviors. However, there is inconsistent evidence for relations between children's baseline vagal tone and their helpful or prosocial responses to others (Hastings & Miller, 2014). Recent work in adults suggests a quadratic…

  14. 78 FR 295 - National Advisory Committee on Institutional Quality and Integrity: Notice of Membership

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-03

    ... University, Atlanta, Georgia. Susan D. Phillips, Ph.D., Provost and Vice President for Academic Affairs, The State University of New York at Albany, Albany, New York. Beter-Aron Shimeles, Student Member..., University of California, Hastings College of the Law, San Francisco, California. Federico Zaragoza, Ph.D...

  15. Comparing Three Estimation Methods for the Three-Parameter Logistic IRT Model

    ERIC Educational Resources Information Center

    Lamsal, Sunil

    2015-01-01

    Different estimation procedures have been developed for the unidimensional three-parameter item response theory (IRT) model. These techniques include the marginal maximum likelihood estimation, the fully Bayesian estimation using Markov chain Monte Carlo simulation techniques, and the Metropolis-Hastings Robbin-Monro estimation. With each…

  16. Bayesian Estimation of Multidimensional Item Response Models. A Comparison of Analytic and Simulation Algorithms

    ERIC Educational Resources Information Center

    Martin-Fernandez, Manuel; Revuelta, Javier

    2017-01-01

    This study compares the performance of two estimation algorithms of new usage, the Metropolis-Hastings Robins-Monro (MHRM) and the Hamiltonian MCMC (HMC), with two consolidated algorithms in the psychometric literature, the marginal likelihood via EM algorithm (MML-EM) and the Markov chain Monte Carlo (MCMC), in the estimation of multidimensional…

  17. 2. AERIAL VIEW SHOWING AQUEDUCT RIGHTOFWAY PASSING OVER RAILROAD LINE ...

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

    2. AERIAL VIEW SHOWING AQUEDUCT RIGHT-OF-WAY PASSING OVER RAILROAD LINE FROM STONE QUARRY. TRACKS ARE GONE BUT RIGHT-OF-WAY IS STILL VISIBLE. - Old Croton Aqueduct, Quarry Railroad Bridge, Aqueduct Lane at Williams Street, Hastings-on-Hudson, Westchester County, NY

  18. LEACHING BOUNDARY IN CEMENT-BASED WASTE FORMS

    EPA Science Inventory

    Cement-based fixation systems are among the most commonly employed stabilization/solidification techniques. These cement haste mixtures, however, are vulnerable to ardic leaching solutions. Leaching of cement-based waste forms in acetic acid solutions with different acidic streng...

  19. Evolutionary outcomes should inform plant breeding and transgenic approaches to drought tolerance in crop species: the importance of xylem traits

    USDA-ARS?s Scientific Manuscript database

    Genomic-assisted breeding and transgenic approaches to crop improvement are presently targeting phenotypic traits that allegedly confer drought tolerance. A news feature published in Nature Biotechnology last year suggests that these efforts may not be proceeding with sufficient haste, considering t...

  20. The Experience of a Man with Severe Challenging Behaviour Following Resettlement from Hospital: A Single Case Design

    ERIC Educational Resources Information Center

    Bissell, Lianne; Phillips, Neil; Kroese, Biza Stenfert

    2005-01-01

    Carers' behaviour is thought to contribute to the development and maintenance of challenging behaviour in people with learning disabilities (Emerson et al. 1995; Hastings & Remington 1994). The present study sought to investigate the effectiveness of a behavioural intervention in the management of such problem behaviours by means of a long-term…

  1. HIDEX-BP Calibrations

    DTIC Science & Technology

    1998-09-30

    Technology March 1997:33-39. Widder, E.A., J.F. Case, S.A. Bernstein, S. MacIntyre, M.R. Lowenstine, M.R. Bowlby , and D.P. Cook. (1993) A new large volume...the 9th International Symposium on Bioluminescence and Chemiluminescence. Eds. JW Hastings, LJ Kricka and PE Stanley. John Wiley & Sons Ltd, Sussex

  2. First North American record of the Palearctic Microplax albofasciata (Costa) (Hemiptera: Lygaeoidea: Oxycarenidae)

    USDA-ARS?s Scientific Manuscript database

    Microplax albofasciata (Costa), a Palearctic (mainly Mediterranean) species of the small family Oxycarenidae, is reported from California as the first record for the New World. Adults of this little-known lygaeoid bug were found in 2012 and 2013 at the Hastings Natural History Reservation in norther...

  3. Expansion of the American elm restoration effort to the upper Midwest

    Treesearch

    James M. Slavicek

    2007-01-01

    The Forestry Sciences Laboratory, Northeastern Research Station, initiated a project in 2003 to restore the American elm in the state of Ohio. This effort has been expanded to the upper Midwest through establishment of a restoration site in Decorah, IA, Eagle Island, WI, and Hastings, MN.

  4. Diffusion-weighted imaging in the prostate: an apparent diffusion coefficient comparison of half-Fourier acquisition single-shot turbo spin-echo and echo planar imaging.

    PubMed

    Babourina-Brooks, Ben; Cowin, Gary J; Wang, Deming

    2012-02-01

    Prostate cancer detection using diffusion-weighted imaging is highly affected by the accuracy of the apparent diffusion coefficient (ADC) values in an image. Echo planar imaging (EPI) is a fast sequence commonly used for diffusion imaging but has inherent magnetic susceptibility and chemical shift artefacts associated. A diffusion sequence that is less affected by these artefacts is therefore advantageous. The half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence was chosen. The diffusion sequences were compared in image quality, repeatability of the ADC value and the effect on the ADC value with varied b values. Eight volunteers underwent three scans of each sequence, on a 1.5-T Siemens system, using b values of 0, 150, 300, 450, 600, 750, 900 and 1000 s/mm(2). ADC maps were created to address the reproducibility of the ADC value when using two b values compared to eight b values. The ADC value using all b values with the HASTE sequence gave the best performance in all tested categories. Both sequences gave significantly different ADC mean values for two b values compared to when using eight b values (P<.05) suggesting larger error is present when using two b values. HASTE was shown to be an improvement over EPI in terms of repeatability, signal variation within a region of interest and standard deviation over the volunteer set. The improved accuracy of the ADC value in the HASTE sequence makes it potentially a more sensitive tumor detection technique.

  5. Their Spirits Live within Us: Aboriginal Women in Downtown Eastside Vancouver Emerging into Visibility

    ERIC Educational Resources Information Center

    Culhane, Dara

    2003-01-01

    The intersection of Main and Hastings streets--known locally as "Pain and Wastings"--marks the heart of Vancouver's inner-city neighborhood: the Downtown Eastside. Since 1997, when the City of Vancouver Health Department declared a public health emergency in response to reports that HIV infection rates among residents exceeded those…

  6. MathBench Biology Modules: Web-Based Math for All Biology Undergraduates

    ERIC Educational Resources Information Center

    Nelson, Karen C.; Marbach-Ad, Gili; Schneider, Katie; Thompson, Katerina V.; Shields, Patricia A.; Fagan, William F.

    2009-01-01

    Historically, biology has not been a heavily quantitative science, but this is changing rapidly (Ewing 2002; Gross 2000; Hastings and palmer 2003; Jungck 2005; Steen 2005). Quantitative approaches now constitute a key tool for modern biologists, yet undergraduate biology courses remain largely qualitative and descriptive. Although biology majors…

  7. "Reading" Mixed Methods Research: Contexts for Criticism

    ERIC Educational Resources Information Center

    Freshwater, Dawn

    2007-01-01

    Health and social care researchers, in their haste to "belong" to academia, have adopted the system of mixed methodology research, overestimating its ability to reveal the truth and occasionally imprisoning their thought in one system. In this article, some of the assumptions underpinning mixed methodology research and its discourse are subjected…

  8. Stochastic Approximation Methods for Latent Regression Item Response Models

    ERIC Educational Resources Information Center

    von Davier, Matthias; Sinharay, Sandip

    2010-01-01

    This article presents an application of a stochastic approximation expectation maximization (EM) algorithm using a Metropolis-Hastings (MH) sampler to estimate the parameters of an item response latent regression model. Latent regression item response models are extensions of item response theory (IRT) to a latent variable model with covariates…

  9. Estimating a Noncompensatory IRT Model Using Metropolis within Gibbs Sampling

    ERIC Educational Resources Information Center

    Babcock, Ben

    2011-01-01

    Relatively little research has been conducted with the noncompensatory class of multidimensional item response theory (MIRT) models. A Monte Carlo simulation study was conducted exploring the estimation of a two-parameter noncompensatory item response theory (IRT) model. The estimation method used was a Metropolis-Hastings within Gibbs algorithm…

  10. Their Spirits Live within Us: Aboriginal Women in Downtown Eastside Vancouver Emerging into Visibility

    ERIC Educational Resources Information Center

    Culhane, Dara

    2003-01-01

    The intersection of Main and Hastings streets--known locally as "Pain and Wastings"--marks the heart of Vancouver's inner-city neighborhood: the Downtown Eastside. Since 1997, when the City of Vancouver Health Department declared a public health emergency in response to reports that HIV infection rates among residents exceeded those…

  11. The Teaching of Ethics. Vol. 1-9.

    ERIC Educational Resources Information Center

    1980

    The state of ethics teaching at the undergraduate and professional school levels is examined in these comprehensive monographs sponsored by the Institute of Society, Ethics and the Life Sciences/The Hastings Center. "The Teaching of Ethics in Higher Education (I)" encompasses: (1) the number and extent of courses in ethics, (2) the status and…

  12. Stochastic Approximation Methods for Latent Regression Item Response Models. Research Report. ETS RR-09-09

    ERIC Educational Resources Information Center

    von Davier, Matthias; Sinharay, Sandip

    2009-01-01

    This paper presents an application of a stochastic approximation EM-algorithm using a Metropolis-Hastings sampler to estimate the parameters of an item response latent regression model. Latent regression models are extensions of item response theory (IRT) to a 2-level latent variable model in which covariates serve as predictors of the…

  13. Type I interferon response is delayed in human astrovirus infections.

    PubMed

    Guix, Susana; Pérez-Bosque, Anna; Miró, Lluïsa; Moretó, Miquel; Bosch, Albert; Pintó, Rosa M

    2015-01-01

    Type I interferon (IFN) activation and its subsequent effects are important in the response to viral infections. Here we show that human astroviruses (HAstVs), which are important agents of acute gastroenteritis in children, induce a mild and delayed IFN response upon infecting CaCo-2 cells. Although IFN-β mRNA is detected within infected cells and supernatant from infected cells show antiviral activity against the replication of other well-known IFN-sensitive viruses, these responses occur at late stages of infection once genome replication has taken place. On the other hand, HAstV replication can be partially reduced by the addition of exogenous IFN, and inhibition of IFN activation by BX795 enhances viral replication, indicating that HAstVs are IFN-sensitive viruses. Finally, different levels of IFN response were observed in cells infected with different HAstV mutants with changes in the hypervariable region of nsP1a/4, suggesting that nsP1a/4 genotype may potentially have clinical implications due to its correlation with the viral replication phenotype and the antiviral responses induced within infected cells.

  14. Analyzing the Participatory Repertoire of a U.S. Educated EFL Teacher in Saudi Arabia

    ERIC Educational Resources Information Center

    Lee-Johnson, Yin Lam

    2016-01-01

    The KSA has become a popular country for Americans to work as an EFL teacher in the recent years because of the payment and cultural experience (Hastings, 2012). Due to the wide social distance between the KSA and USA, the teachers had to adapt to the expectation and become legitimate participants (Lave and Wenger, 1991) in the local communities.…

  15. Action Items

    ERIC Educational Resources Information Center

    Baker, Mark; Keane, Brian

    2009-01-01

    Maximizing school resources and managing a shrinking budget--these are two important items affected when a building's roofing system does not perform properly. Rather than acting in haste, school and university administrators should do what every teacher tells a student prior to answering any question: think through the research and studies to…

  16. Effective Collaboration Among Health Care and Education Professionals: A Necessary Condition for Successful Early Intervention in Rural Areas. Making It Work in Rural Communities. A Rural Network Monograph.

    ERIC Educational Resources Information Center

    Smith-Dickson, Bonnie, Ed.; Hutinger, Patricia, Ed.

    Addressing the lack of cooperation between early intervention programs and the rural health community, this monograph presents eight papers by educators and health professionals who identify specific problems and offer solutions in the form of effective collaboration techniques and model programs. Papers by Susan Hastings and Stewart Gabel…

  17. Clock Genes: Critical Modulators of Breast Cancer Risk

    DTIC Science & Technology

    2005-09-01

    in mammals . Nature 2002, 418:935-941. 10. Hastings MH, Reddy AB, Maywood ES: A clockwork web: Circadian timing in brain and periphery, in health and...disease. Nat Rev Neurosci 2003, 4:649-661. 11. Panda S, Antoch MP, Miller BH, Su Al, Schook AB, Straume M, Schultz PG, Kay SA, Takahashi JS, Hogenesch

  18. Stochastic Approximation Methods for Latent Regression Item Response Models

    ERIC Educational Resources Information Center

    von Davier, Matthias; Sinharay, Sandip

    2010-01-01

    This article presents an application of a stochastic approximation expectation maximization (EM) algorithm using a Metropolis-Hastings (MH) sampler to estimate the parameters of an item response latent regression model. Latent regression item response models are extensions of item response theory (IRT) to a latent variable model with covariates…

  19. The Experience of a Man with Severe Challenging Behaviour Following Resettlement from Hospital: A Single Case Design

    ERIC Educational Resources Information Center

    Bissell, Lianne; Phillips, Neil; Kroese, Biza Stenfert

    2005-01-01

    Carers' behaviour is thought to contribute to the development and maintenance of challenging behaviour in people with learning disabilities (Emerson et al. 1995; Hastings & Remington 1994). The present study sought to investigate the effectiveness of a behavioural intervention in the management of such problem behaviours by means of a long-term…

  20. Extended Mixed-Efects Item Response Models with the MH-RM Algorithm

    ERIC Educational Resources Information Center

    Chalmers, R. Philip

    2015-01-01

    A mixed-effects item response theory (IRT) model is presented as a logical extension of the generalized linear mixed-effects modeling approach to formulating explanatory IRT models. Fixed and random coefficients in the extended model are estimated using a Metropolis-Hastings Robbins-Monro (MH-RM) stochastic imputation algorithm to accommodate for…

  1. Extended Mixed-Efects Item Response Models with the MH-RM Algorithm

    ERIC Educational Resources Information Center

    Chalmers, R. Philip

    2015-01-01

    A mixed-effects item response theory (IRT) model is presented as a logical extension of the generalized linear mixed-effects modeling approach to formulating explanatory IRT models. Fixed and random coefficients in the extended model are estimated using a Metropolis-Hastings Robbins-Monro (MH-RM) stochastic imputation algorithm to accommodate for…

  2. The Effect of an Integrative Parent Education Program on Quality of Life for Families of Children with an Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    White, Caroline Jane

    2010-01-01

    Families of children with an Autism Spectrum Disorder (ASD) exhibit decreases in cohesion and adaptability, increased social isolation (Higgins et al., 2005), higher levels of marital dissatisfaction (Hastings et al., 2005), and overall disruption to daily life (Bristol et al., 1988). Research has provided evidence of higher levels of stress,…

  3. Making Art Invisible: Visual Education and the Cultural Stagnation of Neo-Liberal Rationality

    ERIC Educational Resources Information Center

    Peers, Chris

    2011-01-01

    The popularity of visual literacy may have resulted, in part, from some school authorities rushing the process of determining school curriculum. This article argues that the haste is reflective of pressure placed on educational discourse to conform to neo-liberal reforms of the sector, and is not the result of a careful and complex debate within…

  4. Determinants of Acorn Productivity Among Five Species of Oaks in Central Coastal California

    Treesearch

    Walter D. Koenig; William J. Carmen; Mark T. Stanback; Mumme Ronald L.

    1991-01-01

    We measured acorn production of five species of oaks (genus Quercus) over a ten year period (1980-1989) at Hastings Reservation in Monterey County, California. Crop production was highly variable and generally asynchronous between species. Variance in crop size decreased directly with increasing species diversity across sub-areas within the study...

  5. The need to get smarter on smart grid projects: four Lessons

    SciTech Connect

    2010-10-15

    Significant investments are being made in gadgets and technologies, sometimes without proper analysis of the costs and potential benefits, often without much thought on how the various components of the effort would interface with one another. As often happen when things are done in great haste, there have been setbacks in a number of these initiatives, three of which are highlighted in the article.

  6. "Reading" Mixed Methods Research: Contexts for Criticism

    ERIC Educational Resources Information Center

    Freshwater, Dawn

    2007-01-01

    Health and social care researchers, in their haste to "belong" to academia, have adopted the system of mixed methodology research, overestimating its ability to reveal the truth and occasionally imprisoning their thought in one system. In this article, some of the assumptions underpinning mixed methodology research and its discourse are subjected…

  7. MathBench Biology Modules: Web-Based Math for All Biology Undergraduates

    ERIC Educational Resources Information Center

    Nelson, Karen C.; Marbach-Ad, Gili; Schneider, Katie; Thompson, Katerina V.; Shields, Patricia A.; Fagan, William F.

    2009-01-01

    Historically, biology has not been a heavily quantitative science, but this is changing rapidly (Ewing 2002; Gross 2000; Hastings and palmer 2003; Jungck 2005; Steen 2005). Quantitative approaches now constitute a key tool for modern biologists, yet undergraduate biology courses remain largely qualitative and descriptive. Although biology majors…

  8. Type I Interferon Response Is Delayed in Human Astrovirus Infections

    PubMed Central

    Guix, Susana; Pérez-Bosque, Anna; Miró, Lluïsa; Moretó, Miquel; Bosch, Albert; Pintó, Rosa M.

    2015-01-01

    Type I interferon (IFN) activation and its subsequent effects are important in the response to viral infections. Here we show that human astroviruses (HAstVs), which are important agents of acute gastroenteritis in children, induce a mild and delayed IFN response upon infecting CaCo-2 cells. Although IFN-β mRNA is detected within infected cells and supernatant from infected cells show antiviral activity against the replication of other well-known IFN-sensitive viruses, these responses occur at late stages of infection once genome replication has taken place. On the other hand, HAstV replication can be partially reduced by the addition of exogenous IFN, and inhibition of IFN activation by BX795 enhances viral replication, indicating that HAstVs are IFN-sensitive viruses. Finally, different levels of IFN response were observed in cells infected with different HAstV mutants with changes in the hypervariable region of nsP1a/4, suggesting that nsP1a/4 genotype may potentially have clinical implications due to its correlation with the viral replication phenotype and the antiviral responses induced within infected cells. PMID:25837699

  9. A Rural Community and Its School: Contemporary Insights through Historical Analysis.

    ERIC Educational Resources Information Center

    Moore, Keith

    1999-01-01

    The experiences of two schoolmasters in the small Western Port Bay fishing community of Hastings (Australia) in the last century are presented to provide insights to present-day teachers about the nature of living and teaching in a rural community. The second schoolmaster did a much better job than the first in involving parents in school…

  10. The Interim Superintendent: A Case Study

    ERIC Educational Resources Information Center

    Bigham, Gary; Nix, Susan J.

    2011-01-01

    Considering the vitally important role that the superintendent plays in the overall functioning and wellbeing of any school district, the filling of that position should never be done in haste. Due to the importance of this process and the time it requires, school districts often employ an interim superintendent. In this single case study, one…

  11. The Brave New World of the Interim Superintendency

    ERIC Educational Resources Information Center

    Bigham, Gary D.

    2011-01-01

    Considering the vital role the superintendent plays in the overall functioning and well-being of any school district, the filling of the top leadership post with a permanent appointment never should be done in haste. The process of advertising, reviewing applications, conducting background checks, interviewing candidates, negotiating contracts,…

  12. The Teaching of Ethics. Vol. 1-9.

    ERIC Educational Resources Information Center

    1980

    The state of ethics teaching at the undergraduate and professional school levels is examined in these comprehensive monographs sponsored by the Institute of Society, Ethics and the Life Sciences/The Hastings Center. "The Teaching of Ethics in Higher Education (I)" encompasses: (1) the number and extent of courses in ethics, (2) the status and…

  13. Samuel Gridley Howe and Burton Blatt on True Common Sense.

    ERIC Educational Resources Information Center

    Knoll, James

    1996-01-01

    This paper reflects on comments made by Samuel Gridley Howe in the 19th century and their continuing relevance to the state of institutionalization of individuals with mental retardation. The paper also cites Burton Blatt in his argument in favor of deinstitutionalization with all possible haste despite the inevitable challenges this will pose to…

  14. A Code Division Multiple Access Communication System for the Low Frequency Band.

    DTIC Science & Technology

    1983-04-01

    at the atmos- pheric noise term nA(t). 2.3 Atmospheric Noise LF atmospheric noise is predominantly generated by lightning - strokes . This noise has...T) (j (w (T)/2)J (wR (T)/2)) Ndt (3.66) 0 Equations (3.58) through (3.66) could be used to compare systems employing orthogonal signalling sets to

  15. Comparing Three Estimation Methods for the Three-Parameter Logistic IRT Model

    ERIC Educational Resources Information Center

    Lamsal, Sunil

    2015-01-01

    Different estimation procedures have been developed for the unidimensional three-parameter item response theory (IRT) model. These techniques include the marginal maximum likelihood estimation, the fully Bayesian estimation using Markov chain Monte Carlo simulation techniques, and the Metropolis-Hastings Robbin-Monro estimation. With each…

  16. Bayesian Analysis of Nonlinear Structural Equation Models with Nonignorable Missing Data

    ERIC Educational Resources Information Center

    Lee, Sik-Yum

    2006-01-01

    A Bayesian approach is developed for analyzing nonlinear structural equation models with nonignorable missing data. The nonignorable missingness mechanism is specified by a logistic regression model. A hybrid algorithm that combines the Gibbs sampler and the Metropolis-Hastings algorithm is used to produce the joint Bayesian estimates of…

  17. The Psychometric Properties of the Difficult Behavior Self-Efficacy Scale

    ERIC Educational Resources Information Center

    Oh, Hyun-Kyoung; Kozub, Francis M.

    2010-01-01

    The study was designed to estimate the psychometric properties of Hastings and Brown's (2002a) Difficult Behavior Self-efficacy Scale. Participants were two samples of physical educators teaching in Korea (n = 229) and the United States (U.S.; n = 139). An initial translation of the questionnaire to Korean and pilot study were conducted along with…

  18. The reliability of a heat acclimation state test prescribed from metabolic heat production intensities.

    PubMed

    Willmott, A G B; Hayes, M; Dekerle, J; Maxwell, N S

    2015-10-01

    Acclimation state indicates an individual's phenotypic response to a thermally stressful environment, where changes in heat dissipation capacity are determined during a heat acclimation state test (HAST). Variations in thermoregulatory and sudomotor function are reported while exercising at intensities relative to maximal oxygen uptake. This inter-individual variation is not true when intensity is prescribed to elicit a fixed rate of metabolic heat production (Ḣprod). This study investigated the reliability of peak Tre and two composite measures (sweat gain and sweat setpoint) derived from indices of thermosensitivity during a HAST prescribed from Ḣprod intensities. Fourteen participants (mean±SD; age 23±3 years, stature 174±7cm, body mass 75.0±9.4kg, body surface area 1.9±0.1m(2), peak oxygen consumption [V̇O2peak] 3.49±0.53Lmin(-1)) completed a lactate threshold-V̇O2peak test and two duplicate Ḣprod HASTs on a cycle ergometer. The HAST consisted of three, 30-min periods of exercise at fixed Ḣprod intensities relative to body mass (3, 4.5 and 6Wkg(-1)), within hot dry conditions (44.7±1.8°C and 18.1±4.7% relative humidity). Peak Tre (38.20±0.36 vs. 38.16±0.42°C, p=0.54), sweat setpoint (36.76±0.34 and 36.79±0.38°C, p=0.68) and sweat gain (0.37±0.14 and 0.40±0.18gs(-1)°C(-1), p=0.40) did not differ between HASTs. Typical error of measurement (TEM), coefficient variation (CV) and intra-class coefficient of correlation (ICC) were 0.19°C, 0.5% and 0.80 for peak Tre, 0.21°C, 0.6% and 0.65 for sweat setpoint and 0.09gs(-1)°C(-1), 28% and 0.68 for sweat gain, respectively. The use of fixed Ḣprod intensities relative to body mass is a reliable method for measuring Tre and ascertaining sweat setpoint during a HAST, whereas, sweat gain displays greater variability. A Ḣprod HAST appears sufficiently reliable for quantifying heat acclimation state, where TEM in peak Tre and sweat setpoint are small enough to identify physiologically

  19. Enteric viruses in HIV-1 seropositive and HIV-1 seronegative children with diarrheal diseases in Brazil

    PubMed Central

    Rocha, Monica Simões; Fumian, Tulio Machado; Maranhão, Adriana Gonçalves; de Assis, Rosane Maria; Xavier, Maria da Penha Trindade Pinheiro; Rocha, Myrna Santos; Miagostovich, Marize Pereira; Leite, José Paulo Gagliardi; Volotão, Eduardo de Mello

    2017-01-01

    Diarrheal diseases (DD) have distinct etiological profiles in immune-deficient and immune-competent patients. This study compares detection rates, genotype distribution and viral loads of different enteric viral agents in HIV-1 seropositive (n = 200) and HIV-1 seronegative (n = 125) children hospitalized with DD in Rio de Janeiro, Brazil. Except for group A rotavirus (RVA), which were detected through enzyme immunoassay, the other enteric viruses (norovirus [NoV], astrovirus [HAstV], adenovirus [HAdV] and bocavirus [HBoV]) were detected through PCR or RT-PCR. A quantitative PCR was performed for RVA, NoV, HAstV, HAdV and HBoV. Infections with NoV (19% vs. 9.6%; p<0.001), HBoV (14% vs. 7.2%; p = 0.042) and HAdV (30.5% vs. 14.4%; p<0.001) were significantly more frequent among HIV-1 seropositive children. RVA was significantly less frequent among HIV-1 seropositive patients (6.5% vs. 20%; p<0.001). Similarly, frequency of infection with HAstV was lower among HIV-1 seropositive children (5.5% vs. 12.8%; p = 0.018). Among HIV-1 seropositive children 33 (16.5%) had co-infections, including three enteric viruses, such as NoV, HBoV and HAdV (n = 2) and NoV, HAstV and HAdV (n = 2). The frequency of infection with more than one virus was 17 (13.6%) in the HIV-1 negative group, triple infection (NoV + HAstV + HBoV) being observed in only one patient. The median viral load of HAstV in feces was significantly higher among HIV-1 positive children compared to HIV-1 negative children. Concerning children infected with RVA, NoV, HBoV and HAdV, no statistically significant differences were observed in the medians of viral loads in feces, comparing HIV-1 seropositive and HIV-1 seronegative children. Similar detection rates were observed for RVA, HAstV and HAdV, whilst NoV and HBoV were significantly more prevalent among children with CD4+ T lymphocyte count below 200 cells/mm3. Enteric viruses should be considered an important cause of DD in HIV-1 seropositive children, along with

  20. Foraging patterns of acorn woodpeckers (Melanerpes formicivorus) on valley oak (Quercus lobata Née) in two California oak savanna-woodlands.

    PubMed

    Scofield, Douglas G; Alfaro, Victor Ryan; Sork, Victoria L; Grivet, Delphine; Martinez, Edith; Papp, Jeannette; Pluess, Andrea R; Koenig, Walter D; Smouse, Peter E

    2011-05-01

    Landscape characteristics and social behavior can affect the foraging patterns of seed-dependent animals. We examine the movement of acorns from valley oak (Quercus lobata) trees to granaries maintained by acorn woodpeckers (Melanerpes formicivorus) in two California oak savanna-woodlands differing in the distribution of Q. lobata within each site. In 2004, we sampled Q. lobata acorns from 16 granaries at Sedgwick Reserve in Santa Barbara County and 18 granaries at Hastings Reserve in Monterey County. Sedgwick has lower site-wide density of Q. lobata than Hastings as well as different frequencies of other Quercus species common to both sites. We found acorn woodpeckers foraged from fewer Q. lobata seed source trees (K(g) = 4.1 ± 0.5) at Sedgwick than at Hastings (K(g) = 7.6 ± 0.6) and from fewer effective seed sources (N(em)* = 2.00 and 5.78, respectively). The differences between sites are due to a greater number of incidental seed sources used per granary at Hastings than at Sedgwick. We also found very low levels of seed source sharing between adjacent granaries, indicating that territoriality is strong at both sites and that each social group forages on its own subset of trees. We discovered an interesting spatial pattern in the location of granaries. At Sedgwick, acorn woodpeckers situated their granaries within areas of higher-than-average tree density, while at Hastings, they placed them within areas of lower-than-average tree density, with the outcome that granaries at the two sites were located in areas of similar valley oak density. Our results illustrate that landscape characteristics might influence the number of trees visited by acorn woodpeckers and the locations of territories, while woodpecker social behavior, such as territoriality, shapes which trees are visited and whether they are shared with other social groups.

  1. Molecular epidemiology of enteric viruses in patients with acute gastroenteritis in Aichi prefecture, Japan, 2008/09-2013/14.

    PubMed

    Nakamura, Noriko; Kobayashi, Shinichi; Minagawa, Hiroko; Matsushita, Tadashi; Sugiura, Wataru; Iwatani, Yasumasa

    2016-07-01

    Acute gastroenteritis is a critical infectious disease that affects infants and young children throughout the world, including Japan. This retrospective study was conducted from September 2008 to August 2014 (six seasons: 2008/09-2013/14) to investigate the incidence of enteric viruses responsible for 1,871 cases of acute gastroenteritis in Aichi prefecture, Japan. Of the 1,871 cases, 1,100 enteric viruses were detected in 978 samples, of which strains from norovirus (NoV) genogroup II (60.9%) were the most commonly detected, followed by strains of rotavirus A (RVA) (23.2%), adenovirus (AdV) type 41 (8.2%), sapovirus (SaV) (3.6%), human astrovirus (HAstV) (2.8%), and NoV genogroup I (1.3%). Sequencing of the NoV genogroup II (GII) strains revealed that GII.4 was the most common genotype, although four different GII.4 variants were also identified. The most common G-genotype of RVA was G1 (63.9%), followed by G3 (27.1%), G2 (4.7%) and G9 (4.3%). Three genogroups of SaV strains were found: GI (80.0%), GII (15.0%), and GV (5.0%). HAstV strains were genotyped as HAstV-1 (80.6%), HAstV-8 (16.1%), and HAstV-3 (3.2%). These results show that NoV GII was the leading cause of sporadic acute viral gastroenteritis, although a variety of enteric viruses were detected during the six-season surveillance period.

  2. Air travel and chronic obstructive pulmonary disease: a new algorithm for pre-flight evaluation.

    PubMed

    Edvardsen, Anne; Akerø, Aina; Christensen, Carl C; Ryg, Morten; Skjønsberg, Ole H

    2012-11-01

    The reduced pressure in the aircraft cabin may cause significant hypoxaemia and respiratory distress in patients with chronic obstructive pulmonary disease (COPD). Simple and reliable methods for predicting the need for supplemental oxygen during air travel have been requested. To construct a pre-flight evaluation algorithm for patients with COPD. In this prospective, cross-sectional study of 100 patients with COPD referred to hypoxia-altitude simulation test (HAST), sea level pulse oximetry at rest (SpO(2 SL)) and exercise desaturation (SpO(2 6MWT)) were used to evaluate whether the patient is fit to fly without further assessment, needs further evaluation with HAST or should receive in-flight supplemental oxygen without further evaluation. HAST was used as the reference method. An algorithm was constructed using a combination of SpO(2 SL) and SpO(2 6MWT). Categories for SpO(2 SL) were >95%, 92-95% and <92%, the cut-off value for SpO(2 6MWT) was calculated as 84%. Arterial oxygen pressure (PaO(2 HAST)) <6.6 kPa was the criterion for recommending supplemental oxygen. This algorithm had a sensitivity of 100% and a specificity of 80% when tested prospectively on an independent sample of patients with COPD (n=50). Patients with SpO(2 SL) >95% combined with SpO(2 6MWT) ≥84% may travel by air without further assessment. In-flight supplemental oxygen is recommended if SpO(2 SL)=92-95% combined with SpO(2 6MWT) <84% or if SpO(2 SL) <92%. Otherwise, HAST should be performed. The presented algorithm is simple and appears to be a reliable tool for pre-flight evaluation of patients with COPD.

  3. Detection of intracranial hemorrhage with susceptibility-weighted MR sequences.

    PubMed

    Liang, L; Korogi, Y; Sugahara, T; Shigematsu, Y; Okuda, T; Ikushima, I; Takahashi, M

    1999-09-01

    Detection of hemorrhage is important in the diagnosis and management of a variety of intracranial diseases. We evaluated the sensitivity of the following sequences for depicting chronic hemorrhagic foci associated with susceptibility dephasing: gradient-recalled echo (GRE) imaging, GRE-type single-shot echo-planar imaging (GRE-EPI), spin-echo-type single-shot echo-planar imaging (SE-EPI), turbo spin-echo (TSE) imaging, half-Fourier single-shot turbo spin-echo (HASTE) imaging, and segmented HASTE (s-HASTE) imaging. To our knowledge, no previous comparison has been made with these techniques in the same patient. Fifty patients with suspected chronic hemorrhage were examined prospectively with the above six sequences. Contrast-to-noise ratio (CNR), sensitivity to detection of lesions, conspicuity of internal architecture, and sensitivity to small hemorrhagic foci were evaluated. Hemorrhagic foci were found in 35 patients. The CNR of the GRE, GRE-EPI, SE-EPI, TSE, s-HASTE, and HASTE sequences was 30.9, 23.7, 3.6, 6.1, -29.3, and -13.1, respectively; the number of small hemorrhagic foci detected was 85, 96, 44, 22, two, and one, respectively, for the supratentorial white matter; 70, 40, 19, four, zero, and zero, respectively, for the supratentorial cortical/subcortical region; and 73, 50, 26, 37, zero, and zero, respectively, for the infratentorial/skull-base region. The GRE sequence was best for detecting susceptibility dephasing associated with chronic intracranial hemorrhage. GRE-EPI, while comparable to GRE in the supratentorial compartment, was reduced in its sensitivity near the skull base, and may be used as an alternative to GRE in uncooperative, unsedated, pediatric, or claustrophobic patients. SE-EPI should not be used in screening for intracranial hemorrhage.

  4. Emerging trends in the epidemiology of human astrovirus infection among infants, children and adults hospitalized with acute watery diarrhea in Kolkata, India.

    PubMed

    Pativada, Madhusudhan; Nataraju, Seegekote Mariyappa; Ganesh, Balasubramanian; Rajendran, Krishnan; Ramamurthy, Thandavarayan; Ganguly, Sandipan; Bhattacharya, Mihir Kumar; Ghosh, Mrinmoy; Kobayashi, Nobumichi; Krishnan, Triveni

    2012-12-01

    Human astroviruses (HAstVs) have now emerged as another common cause of non-bacterial acute gastroenteritis (AGE) in humans worldwide. This study investigated the epidemiology and genetic diversity of human astrovirus strains circulating among infants, younger children (up to 6 years), older children and adolescents (>6-17 years) and adults (18 years and above) hospitalized for diarrhea and their role in AGE in Kolkata, India. A total of 2535 fecal samples were screened for the presence of known enteric viral, bacterial and parasitic etiologies by conventional microbiological assays and molecular methods. The overall incidences of sole or mixed infection of HAstV with known enteric viral, bacterial and parasitic pathogens were detected in 60 cases (2.4%) among all age groups. The clinical symptoms of astrovirus-associated acute watery diarrhea cases were recorded for all sole and mixed infection cases. A high number of sole (n = 13/60 [21.7%]) and mixed infection cases (n = 22/60 [36.7%]) were observed in adults (18 years old or more). Considering all age groups, 18 sole infection cases (n = 18/60 [30%]) and 42 mixed infection cases (n = 42/60 [70%]) with Rotavirus (n = 11/25 [44%]), Vibrio cholerae O1 (n = 6/24 [25%]) Cryptosporidium spp and Giardia lamblia (n = 5/13 [38.4%]) were observed. Further, eleven HAstV samples from infants and children (up to 6 years), children and adolescents (>6-17 years) and adults (18 years and above) were analyzed for their sequences of overlap region between ORF1b (RdRp) and ORF2 (capsid). Among these, ten strains were found to have close genetic relatedness to the Japanese strain HAstV_G1 [AB009985]. Additionally, the IDH2211 Kolkata strain showed a close genetic match with the Thai HAstV_G3 strain [EU363889]. Our study reports show that HAstVs as the sole agent and as mixed infection with other known enteric viral, bacterial, parasitic pathogens are also responsible for AGE among infants, children, adolescents and adults in

  5. Fairness, health, and access.

    PubMed

    Gusmano, Michael

    2013-01-01

    During the past two years, much of my work at The Hastings Center has explored the implementation of health reform in the United States and its implications for poor and vulnerable groups. These projects include a study of access to care for undocumented patients and one that examines state-level decisions about health reform, including Medicaid expansion and the creation of health insurance "marketplaces." Both raise issues central to bioethics, including fairness, justice, and the stewardship of society's resources. Our nation spent about 2.7 trillion dollars on health care in 2012, and its major public health insurance programs represent over 20 percent of the federal budget. Despite these investments, there are troubling differences in life expectancy, infant mortality, and premature death depending on factors like income, race, ethnicity, gender, and where people live. © 2013 by The Hastings Center.

  6. LETTER TO THE EDITOR: No sliding in time

    NASA Astrophysics Data System (ADS)

    Shtengel, Kirill; Nayak, Chetan; Bishara, Waheb; Chamon, Claudio

    2005-09-01

    In this letter, we analyse the following apparent paradox: as has been recently proved by Hastings (2004 Phys. Rev. 69 104431), under a general set of conditions, if a local Hamiltonian has a spectral gap above its (unique) ground state (GS), all connected equal-time correlation functions of local operators decay exponentially with distance. On the other hand, statistical mechanics provides us with examples of 3D models displaying so-called sliding phases (O'Hern et al 1999 Phys. Rev. Lett. 83 2745) which are characterized by the algebraic decay of correlations within 2D layers and exponential decay in the third direction. Interpreting this third direction as time would imply a gap in the corresponding (2+1)D quantum Hamiltonian which would seemingly contradict Hastings' theorem. The resolution of this paradox lies in the non-locality of such a quantum Hamiltonian.

  7. Modelling maximum river flow by using Bayesian Markov Chain Monte Carlo

    NASA Astrophysics Data System (ADS)

    Cheong, R. Y.; Gabda, D.

    2017-09-01

    Analysis of flood trends is vital since flooding threatens human living in terms of financial, environment and security. The data of annual maximum river flows in Sabah were fitted into generalized extreme value (GEV) distribution. Maximum likelihood estimator (MLE) raised naturally when working with GEV distribution. However, previous researches showed that MLE provide unstable results especially in small sample size. In this study, we used different Bayesian Markov Chain Monte Carlo (MCMC) based on Metropolis-Hastings algorithm to estimate GEV parameters. Bayesian MCMC method is a statistical inference which studies the parameter estimation by using posterior distribution based on Bayes’ theorem. Metropolis-Hastings algorithm is used to overcome the high dimensional state space faced in Monte Carlo method. This approach also considers more uncertainty in parameter estimation which then presents a better prediction on maximum river flow in Sabah.

  8. Ethical and policy issues in rehabilitation medicine.

    PubMed

    Caplan, Arthur L; Callahan, Daniel; Haas, Janet

    1987-08-01

    The field of medical rehabilitation is relatively new.... Until recently, the ethical problems of this new field were neglected. There seemed to be more pressing concerns as rehabilitation medicine struggled to establish itself, sometimes in the face of considerable skepticism or hostility. There also seemed no pressing moral questions of the kind and intensity to be encountered, say, in high-technology acute care medicine or genetic engineering.... Those in biomedical ethics could and did easily overlook the quiet, less obtrusive issues of rehabilitation.... The Hastings Center set out in 1985 to rectify that situation.... To explore the issues, the Center assembled a group of practitioners in the field, Hastings Center staff members, and individuals experienced in other areas of medical ethics.... The report that follows was written by Arthur Caplan and Daniel Callahan, assisted by Dr. Janet Haas of the Moss Rehabilitation Hospital in Philadelphia....

  9. Learning about Teaching.

    PubMed

    Kaebnick, Gregory E

    2014-09-01

    There are three broad themes in this issue of the Hastings Center Report. First, a special report published as a supplement to the issue addresses the medical and health policy issues faced by lesbian, gay, bisexual, and transgender patients. Inside the issue, the two articles take up questions about how caregivers may justify a refusal to provide a medical service that a patient has requested. The issue also contains a set of essays that have emerged from a collaborative effort by The Hastings Center and the Presidential Commission for the Study of Bioethical Issues to promote scholarly engagement with the practical problem of teaching caregivers, researchers, scientists, and others to address bioethical problems. What appears here is the first installment of a series that will appear in the pages of the Report well into the 2015 volume.

  10. Lung Cancer Pathological Image Analysis Using a Hidden Potts Model.

    PubMed

    Li, Qianyun; Yi, Faliu; Wang, Tao; Xiao, Guanghua; Liang, Faming

    2017-01-01

    Nowadays, many biological data are acquired via images. In this article, we study the pathological images scanned from 205 patients with lung cancer with the goal to find out the relationship between the survival time and the spatial distribution of different types of cells, including lymphocyte, stroma, and tumor cells. Toward this goal, we model the spatial distribution of different types of cells using a modified Potts model for which the parameters represent interactions between different types of cells and estimate the parameters of the Potts model using the double Metropolis-Hastings algorithm. The double Metropolis-Hastings algorithm allows us to simulate samples approximately from a distribution with an intractable normalizing constant. Our numerical results indicate that the spatial interaction between the lymphocyte and tumor cells is significantly associated with the patient's survival time, and it can be used together with the cell count information to predict the survival of the patients.

  11. Toward Public Bioethics?

    PubMed

    Kaebnick, Gregory E

    2017-05-01

    This issue of the Hastings Center Report (May-June 2017) features a couple of interesting takes on the governance challenges of emerging technologies. In an essay on the National Academies of Science, Engineering, and Medicine report published this February on human germ-line gene editing, Eric Juengst, a philosopher at the University of North Carolina, argues that the NASEM committee did not manage to rethink the rules. Juengst reaches what he calls an "eccentric conclusion": "The committee's 2017 consensus report has been widely interpreted as 'opening the door' to inheritable human genetic modification and holding a line against enhancement interventions. But on a close reading it does neither." In the column Policy and Politics, Sarah Chan, a chancellor's fellow at the University of Edinburgh, discusses the emerging science of "organoids," "embryoids," and "synthetic human entities with embryo-like features" and calls for a sustained effort to rethink the rules for embryo research. © 2017 The Hastings Center.

  12. Lung Cancer Pathological Image Analysis Using a Hidden Potts Model

    PubMed Central

    Li, Qianyun; Yi, Faliu; Wang, Tao; Xiao, Guanghua; Liang, Faming

    2017-01-01

    Nowadays, many biological data are acquired via images. In this article, we study the pathological images scanned from 205 patients with lung cancer with the goal to find out the relationship between the survival time and the spatial distribution of different types of cells, including lymphocyte, stroma, and tumor cells. Toward this goal, we model the spatial distribution of different types of cells using a modified Potts model for which the parameters represent interactions between different types of cells and estimate the parameters of the Potts model using the double Metropolis-Hastings algorithm. The double Metropolis-Hastings algorithm allows us to simulate samples approximately from a distribution with an intractable normalizing constant. Our numerical results indicate that the spatial interaction between the lymphocyte and tumor cells is significantly associated with the patient’s survival time, and it can be used together with the cell count information to predict the survival of the patients. PMID:28615918

  13. Recent Advances in Spacecraft Charging

    DTIC Science & Technology

    1994-03-08

    divergence. The with partial successes [Cohen, etal., 1981; Cohen and transverse energy gained by a diverging beam Lai, 1982; Olsen , 1985; Werner, 1988]. When...probes, J AppL Phys., Technology Conference, R.C. Olsen (ed), Naval 63, 5674-5677, 1988. Postgraduate School, Mornterey, 1989. Neubert, T., MJ...Dec., 1993. Olsen , R.C., Modification of spacecraft potentials by Wang, J. and D.E_ Hastings, Ionospheric plasma flow plasma emission, J. Spacecraft

  14. Ethics committees and cost containment.

    PubMed

    Brock, D W

    1990-01-01

    Cohen introduces a section of articles on hospital ethics committees that appears twice a year in the Hastings Center Report. Articles by Dan W. Brock, Alan R. Fleischman, Suzanne M. Mitchell and Martha S. Swartz, and Janet Fleetwood support the idea that hospital ethics committees are performing a needed service. Ethics committees have been in existence long enough, however, to begin to explore new issues and activities.

  15. An Investigation of the Pareto Distribution as a Model for High Grazing Angle Clutter

    DTIC Science & Technology

    2011-03-01

    The Pareto Distribution [1-3] is named after the Italian economist Vilfredo Pareto (15 July 1848 – 19 August 1923) [4, 5], and is a power law...1980). 3. Evans, M., Hastings, N. and Peacock, B., Statistical Distributions, 3rd Edition, (Wiley, New York, 2000). 4. Bruno, G. “ Pareto , Vilfredo ” The...New Palgrave: A Dictionary of Economics, 5, 799804, 1987. 5. Cirillo, R. The Economics of Vilfredo Pareto , (Frank Cass Publishers, 1978) 6. Aban, I. B

  16. Taming the Tigers: Recapturing the Acquisition Excellence of Our Planning, Programming, and Acquisition Three-Ring Circus

    DTIC Science & Technology

    2013-04-01

    like to thank the following individuals for their incisive thinking and constructive edits: Gen Jim McCarthy (retired), Prof. Dan Hastings, Prof...Richard de Neufville, Prof. Gautam Mukunda, Col Glenn Downing, Col Chris Garrett, Col Jim Lovell, Col Troy Thomas, Bill Castle, Mike Kalna, Carl Rehberg...MIT Press, 2011); Nassim Nicholas Taleb, The Black Swan : The Impact of the Highly Im- probable, 2nd ed. (New York: Random House Trade Paperbacks, 2010

  17. de Finetti Priors using Markov chain Monte Carlo computations.

    PubMed

    Bacallado, Sergio; Diaconis, Persi; Holmes, Susan

    2015-07-01

    Recent advances in Monte Carlo methods allow us to revisit work by de Finetti who suggested the use of approximate exchangeability in the analyses of contingency tables. This paper gives examples of computational implementations using Metropolis Hastings, Langevin and Hamiltonian Monte Carlo to compute posterior distributions for test statistics relevant for testing independence, reversible or three way models for discrete exponential families using polynomial priors and Gröbner bases.

  18. de Finetti Priors using Markov chain Monte Carlo computations

    PubMed Central

    Bacallado, Sergio; Diaconis, Persi; Holmes, Susan

    2015-01-01

    Recent advances in Monte Carlo methods allow us to revisit work by de Finetti who suggested the use of approximate exchangeability in the analyses of contingency tables. This paper gives examples of computational implementations using Metropolis Hastings, Langevin and Hamiltonian Monte Carlo to compute posterior distributions for test statistics relevant for testing independence, reversible or three way models for discrete exponential families using polynomial priors and Gröbner bases. PMID:26412947

  19. New applications of Schrödinger type inequalities to the existence and uniqueness of Schrödingerean equilibrium.

    PubMed

    Wang, Jianjie; Roncalver, Hugo

    2017-01-01

    As new applications of Schrödinger type inequalities appearing in Jiang (J. Inequal. Appl. 2016:247, 2016), we first investigate the existence and uniqueness of a Schrödingerean equilibrium. Next we propose a tritrophic Hastings-Powell model with two different Schrödingerean time delays. Finally, the stability and direction of the Schrödingerean Hopf bifurcation are also investigated by using the center manifold theorem and normal form theorem.

  20. Monte-Carlo Inversion of Travel-Time Data for the Estimation of Weld Model Parameters

    NASA Astrophysics Data System (ADS)

    Hunter, A. J.; Drinkwater, B. W.; Wilcox, P. D.

    2011-06-01

    The quality of ultrasonic array imagery is adversely affected by uncompensated variations in the medium properties. A method for estimating the parameters of a general model of an inhomogeneous anisotropic medium is described. The model is comprised of a number of homogeneous sub-regions with unknown anisotropy. Bayesian estimation of the unknown model parameters is performed via a Monte-Carlo Markov chain using the Metropolis-Hastings algorithm. Results are demonstrated using simulated weld data.

  1. JPRS Report, East Asia, Southeast Asia

    DTIC Science & Technology

    1988-07-11

    Tatmadaw Camps 3 Editorial on Revenues, Tax Collection , 3 INDONESIA Minister Discloses Readiness To Utilize GSP 4 Preparations for Further Trade...Soeharto’ [Peter Hastings; THE SYDNEY MORNING HERALD, 17 May 88] 7 Javanese Political Processes, Possible Threats to Australia Discussed [Peter...and revenues as prescribed by law. /9274 /9274 JPRS-SEA-88-029 11 July 1988 INDONESIA Minister Discloses Readiness To Utilize GSP 42130130a

  2. Worldwide Report, Arms Control.

    DTIC Science & Technology

    1985-10-18

    frenzied haste in nuclear and conventional armament and the extensive preparation of the corresponding infrastructures in the prospective theaters...use of U.S.-made chemical weapons in Afghanistan. Nerve gas was used during the U.S. invasion of Grenada, as the Mexican DIA newspaper has reported...consent to the situation when the population of their countries would live close to tonnes of nerve , choking and other toxic substances. In the event

  3. Assessment of gastroenteric viruses from wastewater directly discharged into Uruguay River, Uruguay.

    PubMed

    Victoria, M; Tort, L F L; García, M; Lizasoain, A; Maya, L; Leite, J P G; Miagostovich, M P; Cristina, J; Colina, R

    2014-06-01

    The aim of this study was to assess the viral contamination of group A rotavirus (RVA), norovirus (NoV), and human astrovirus (HAstV) in sewage directly discharged into Uruguay River and to characterize RVA genotypes circulating in Uruguay. For this purpose, sewage samples (n = 96) were collected biweekly from March 2011 to February 2012 in four Uruguayan cities: Bella Unión, Salto, Paysandú, and Fray Bentos. Each sample was concentrated by ultracentrifugation method. Qualitative and quantitative RT-PCR for RVA, NoV, and HAstV were performed. A wide dissemination of gastroenteric viruses was observed in the sewage samples analyzed with 80% of positivity, being NoV (51%) the most frequently detected followed by RVA with a frequency of 49% and HAstV with 45%. Genotypes of RVA were typed using multiplex semi-nested RT-PCR as follows: P[8] (n = 15), P[4] (n = 8), P[10] (n = 1), P[11] (n = 1), G2 (n = 29), and G3 (n = 2). The viral load ranged from 10(3) to 10(7) genomic copies/liter, and they were detected roughly with the same frequency in all participant cities. A peak of RVA and HAstV detection was observed in colder months (June to September), whereas no seasonality was observed for NoV. This study demonstrates for the first time, the high degree of gastroenteric viral contamination in the country; highlighting the importance of developing these analyses as a tool to determine the viral contamination in this hydrographic boundary region used by the local populations for recreation and consumption, establishing an elevated risk of gastroenteric diseases for human health.

  4. Astrovirus VA1/HMO-C: An Increasingly Recognized Neurotropic Pathogen in Immunocompromised Patients

    PubMed Central

    Brown, Julianne R.; Morfopoulou, Sofia; Hubb, Jonathan; Emmett, Warren A.; Ip, Winnie; Shah, Divya; Brooks, Tony; Paine, Simon M. L.; Anderson, Glenn; Virasami, Alex; Tong, C. Y. William; Clark, Duncan A.; Plagnol, Vincent; Jacques, Thomas S.; Qasim, Waseem; Hubank, Mike; Breuer, Judith

    2015-01-01

    Background. An 18-month-old boy developed encephalopathy, for which extensive investigation failed to identify an etiology, 6 weeks after stem cell transplant. To exclude a potential infectious cause, we performed high-throughput RNA sequencing on brain biopsy. Methods. RNA-Seq was performed on an Illumina Miseq, generating 20 million paired-end reads. Nonhost data were checked for similarity to known organisms using BLASTx. The full viral genome was sequenced by primer walking. Results. We identified an astrovirus, HAstV-VA1/HMO-C-UK1(a), which was highly divergent from human astrovirus (HAstV 1–8) genotypes, but closely related to VA1/HMO-C astroviruses, including one recovered from a case of fatal encephalitis in an immunosuppressed child. The virus was detected in stool and serum, with highest levels in brain and cerebrospinal fluid (CSF). Immunohistochemistry of the brain biopsy showed positive neuronal staining. A survey of 680 stool and 349 CSF samples identified a related virus in the stool of another immunosuppressed child. Conclusions. The discovery of HAstV-VA1/HMO-C-UK1(a) as the cause of encephalitis in this case provides further evidence that VA1/HMO-C viruses, unlike HAstV 1–8, are neuropathic, particularly in immunocompromised patients, and should be considered in the differential diagnosis of encephalopathy. With a turnaround from sample receipt to result of <1 week, we confirm that RNA-Seq presents a valuable diagnostic tool in unexplained encephalitis. PMID:25572899

  5. 23 CFR Appendix A to Part 658 - National Network-Federally-Designated Routes

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... US 61 WI State Line MN 60 Wabasha. US 61 MN 55 Hastings I-94 St. Paul. US 61 I-35 Duluth CH 2 Two... 32 Thief River Falls. MN 3 MN 110 Inver Grove Hts I-94 St. Paul. MN 5 MN 22 Gaylord US 212. MN 7 US... Little Falls US 2 Cass Lake. NOTE: I-35E St. Paul—The parkway segment of I-35E from 7th Street to I-94...

  6. Investigation of Processes and Factors Regulating the Generation, Maintenance and Breakdown of Bioluminescent Thin Layers

    DTIC Science & Technology

    2001-09-30

    field study in Wilkinson Basin in collaboration with Dr. Joe Katz of Johns Hopkins Univer­ sity. Thin layers were located using the High-Intake...blue fins. After the deployment, and during the second year the Johns Hopkins group focused on developing automatic processing procedures for...on Bioluminescence and Chemiluminescence. Eds. JW Hastings, LJ Kricka and PE Stanley. John Wiley & Sons Ltd, Sussex, UK. pp. 159-164. Widder, EA

  7. A Bayesian Approach to Identifying Structural Nonlinearity using Free-Decay Response: Application to Damage Detection in Composites

    DTIC Science & Technology

    2010-03-03

    methods in structural dynamics. A general Bayesian approach to structural dynamics problems was put forth in the ’90s with works by Beck and Katafygiotis...for solving high-dimensional integrals in particle physics. A later work by Hastings [18] extended this general approach, resulted in what is now known...approach is certainly more general and could be applied to forced structures as well. However, in practice the forcing function is not always

  8. Index to USA Aviation Digest, 1991

    DTIC Science & Technology

    1992-11-01

    Aviation Digest; Nov-Dec 1991: p. 42. CIPPS SEE CIVILIAN INTEGRATION INTO THE PERSONNEL PROPONENCY SYSTEM ( CIPPS ) CIVILIAN INTEGRATION INTO THE PERSONNEL...PROPONENCY SYSTEM ( CIPPS ) Civilian integration into the Personnel Proponency System ( CIPPS ). USA Aviation Digest; Jul-Aug 1991: p. 28. CMIF SEE...HASTINGS, ROBERT T. Twenty commandments for platoon leaders. USA Aviation Digest; Mar-Apr 1991: p. 30-31. HAYES, THOMAS M. Delta models at the

  9. The TRACE Model of Speech Perception.

    DTIC Science & Technology

    1984-11-01

    One approach is to try to find relatively invariant -- generally relational -- features (e.g., Stevens and Blumstein, 1981). Another approach has...t Dr. Anders Ericsson I Dr. Steven W. Keele Department oi Psychology Dept. of Psychology University of Colorado University of Oregon Boulder, CO...Parallel distributed processing: Explorations in the microstructue of cogni- tion. Vol. 1: Foundations. Cambridge, MA: Bradford Books. Stevens , K

  10. Deciphering the Diversities of Astroviruses and Noroviruses in Wastewater Treatment Plant Effluents by a High-Throughput Sequencing Method

    PubMed Central

    Prevost, B.; Lucas, F. S.; Ambert-Balay, K.; Pothier, P.; Wurtzer, S.

    2015-01-01

    Although clinical epidemiology lists human enteric viruses to be among the primary causes of acute gastroenteritis in the human population, their circulation in the environment remains poorly investigated. These viruses are excreted by the human population into sewers and may be released into rivers through the effluents of wastewater treatment plants (WWTPs). In order to evaluate the viral diversity and loads in WWTP effluents of the Paris, France, urban area, which includes about 9 million inhabitants (approximately 15% of the French population), the seasonal occurrence of astroviruses and noroviruses in 100 WWTP effluent samples was investigated over 1 year. The coupling of these measurements with a high-throughput sequencing approach allowed the specific estimation of the diversity of human astroviruses (human astrovirus genotype 1 [HAstV-1], HAstV-2, HAstV-5, and HAstV-6), 7 genotypes of noroviruses (NoVs) of genogroup I (NoV GI.1 to NoV GI.6 and NoV GI.8), and 16 genotypes of NoVs of genogroup II (NoV GII.1 to NoV GII.7, NoV GII.9, NoV GII.12 to NoV GII.17, NoV GII.20, and NoV GII.21) in effluent samples. Comparison of the viral diversity in WWTP effluents to the viral diversity found by analysis of clinical data obtained throughout France underlined the consistency between the identified genotypes. However, some genotypes were locally present in effluents and were not found in the analysis of the clinical data. These findings could highlight an underestimation of the diversity of enteric viruses circulating in the human population. Consequently, analysis of WWTP effluents could allow the exploration of viral diversity not only in environmental waters but also in a human population linked to a sewerage network in order to better comprehend viral epidemiology and to forecast seasonal outbreaks. PMID:26253673

  11. ’Stinger under Armor:’ An Analysis of Alternatives

    DTIC Science & Technology

    1990-01-01

    Military Effectiveness 1914-1945," Lieutenant General John H. Cushman, U.S. Army, Retired, wrote: Our histories tell us that -- whether it be through...Air Defense 1988- 1989. Surrey, U.K.: Jane’s Information Group, 1988. Cushman, John H. Challenge & Response: Military Effectiveness 1914-1945...Mideast Research, 1980. English, John A. On infintry. New York: Praeger Publishers, 1984. Hastings, Max, and Simon Jenkins. The Battle For the Falklands

  12. Reactions of Atmospheric Species with Clean and H, C, and O Implanted Species

    DTIC Science & Technology

    1989-07-27

    elegant approach to the simulation of a number of these phenomena in the controlled environment of ultra-high vacuum. Qualitative and quantitative argu...skienc haste to a number of tsxhnslougcAl phen rini and represent art elegant approach ti the simulation of a number ill these phenoimena in the...hypersurface. Recently. the importance of such ion-atom potentials in atom ejection sequences during reactive ion bombardment simulations has been

  13. A Method Using Epoch-Era Analysis to Identify Valuable Changeability in System Design

    DTIC Science & Technology

    2011-04-01

    2005) published a paper summarizing unifying principles behind designing for changeability ( DfC ) in engineering. In addition to covering the motivation...changeability of designs and not of the designing process. According to DfC , robustness is the ability of a system to withstand environmental changes... DfC ): Principles to enable changes in systems throughout their entire lifecycle,” Systems Engineering, vol. 8, 2005, pp. 342-359. Hastings, D.E

  14. Half Fourier single-shot turbo spin-echo magnetic resonance urography for the evaluation of suspected renal colic in pregnancy.

    PubMed

    Mullins, Jeffrey K; Semins, Michelle J; Hyams, Elias S; Bohlman, Mark E; Matlaga, Brian R

    2012-06-01

    To report our experience with magnetic resonance urography (MRU) in pregnant women suspected of having obstructing upper tract calculi. The diagnosis of an upper tract calculus in the pregnant woman can be challenging. Recent evidence suggests that MRU can be used to effectively evaluate renal colic. From 2008-2011, 9 pregnant women were referred for evaluation of suspected renal colic caused by an obstructing upper tract stone. All patients underwent MRU with a half Fourier single-shot turbo spin-echo (HASTE) protocol. Medical records and imaging studies were reviewed for demographic and clinical data as well as outcome measures. The mean age of the subjects was 25 years (range 20-34); average gestational age of the fetus was 23 weeks (range 9-36). In all cases, a renal ultrasound was the initial imaging study obtained, with nondiagnostic findings. HASTE MRU detected 4 ureteral stones and 4 cases of physiological hydronephrosis of pregnancy. In one case, interpretation of the MRU was limited as a result of patient motion. Of the patients with obstructing stones, 1 required endourologic management during her pregnancy and 3 were followed conservatively. No adverse events related to MRU occurred. HASTE MRU is an informative imaging study for pregnant women with suspected upper tract stone disease. Information gathered from this study augments that gained from alternative modalities, and aids in medical decision-making. The lack of ionizing radiation exposure, coupled with the capture of detailed anatomic imaging, makes HASTE MRU a particularly useful study in this setting. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Pulse Power Switch Development

    DTIC Science & Technology

    1980-10-01

    Electron Devices, Vol ED-26, pgs 1411-1413, October 1979. 3. J. Kopainsky, "Influence of the Arc on Breakdown Phenomena in Circuit Breakers ", pg. 329 in...Mechanics, Addison Wesley, Reading, 1959. ) 17. Sig Hansen HRL Report #514, Aerodynamics of Gas Blast in the In-Line Circuit Breaker . 18. J.B. Hasted...nonrepetitive) ....... ............... . 21 9 Test circuit for VSFS .... .............. 24 10 Test model VSFS and sample insulator inserts .. .. 26

  16. Bayesian Ambient Noise Inversion for Geoacoustic Uncertainty Estimation

    DTIC Science & Technology

    2013-09-30

    for numerical estimation of the posterior probability density (PPD) over the geoacoustic parameters of interest: Since analytical solutions for the PPD...work, Metropolis-Hastings sampling (MHS) is applied to determine marginal probability densities. Perturbations are applied in a principal-component...reflection coefficient estimated by beamforming using the true parameters (top) from (a) and the most probable model obtained via inversion (bottom), at

  17. Progress in Military Airlift: The Flight Mechanics Panel Symposium Held in Lisbon, Portugal on 28-31 May 1990 (Les Progres Realises dans le Domaine du Transport Aerien Militaire)

    DTIC Science & Technology

    1990-12-01

    Respiratory Protection - A Military Airlift Command Perspective, 12 Evaluation of a New Fuel with Higher Energy Density, 13 by PXEf)esmier and RR.Hastings...8217Amarenees, A Safety Challenge,’ The International JO-ural of Av&atLon Safety, September 1964, pp. 181-182. 12-1 Aircrew Eye/ Respiratory Protection A...effort to improve aircrew eye/ respiratory protection (AERP) in the chemical defense environment. It discusses the signifiunnt effort to plan the concept

  18. Enhanced Research to Create More Jobs

    SciTech Connect

    Agnihotri, Newal, K.

    2004-03-01

    Mr. Doc Hastings, U.S. Congressman from the state of Washington is interviewed regarding various topics related to the nuclear energy picture in the US. Topics include the level of public support for nuclear energy, differences between the roles for state and federal governments, job creation, clean-up briefings, a Yucca Mountain status, a hydrogen-nuclear status, the role of nuclear energy in Kyoto protocol compliance, and the market for power plants.

  19. Concepts for Data Collection in the Arctic

    DTIC Science & Technology

    1972-05-01

    Weather Service. NOAA, U.S. Department of Commerce , October 1970. 7. Hastings, A. D. Jr. Arctic Basin--Locations of Climatic Stations. U.S. Army Engineer...flat deck version of the ACV, known as the Voyageur , in the central Canadian Arctic. The flatbed design offers flexibility in configuring the vehicle...range of 300 miles for the Voyageur at average cruising speeds of 30 mph for full fuel capacity. In August 1971, a predecessor model of this craft (the

  20. Concepts for Data Collection in the Arctic

    DTIC Science & Technology

    1972-05-01

    Francisco/Point Barrow, January-August 1971. 6. Operations of the National Weather Service. NOAA, U.S. Department of Commerce , October 1970. 7. Hastings... Voyageur , in the central Canadian Arctic. The flatbed design offers flexibility in configuring the vehicle for multimission operation (e.g., supply...comprising working laboratories, housing, and data collection and recording facilities. The manufacturer claims a range of 300 miles for the Voyageur at

  1. Molecular Probes in Marine Ecology: Concepts, Techniques and Applications.

    DTIC Science & Technology

    1991-08-16

    bacterial Woody Hastings: bioluminescence . 20 Wed. Paul Dunlap: The lux genes in bacteria : organization, structure, and expression. 21 Thurs. Chuck...probes for microbial identification. Ken Nealson: Taxonomy physiology and distribution of marine bioluminescent bacteria . 10 Tues. Ann Bucklin: Allozymic...cuponsored with the microbiology course, the first of these being on bioluminescence and symbiosis on July 7, and the second on molecular approaches to

  2. Comparison of Hall Thruster Plume Expansion Model with Experimental Data

    DTIC Science & Technology

    2006-05-23

    focus of this study, is a hybrid particle- in-cell ( PIC ) model that tracks particles along an unstructured tetrahedral mesh. * Research Engineer...measurements of the ion current density profile, ion energy distributions, and ion species fraction distributions using a nude Faraday probe, retarding...Vol.37 No.1. 6 Oh, D. and Hastings, D., “Three Dimensional PIC -DSMC Simulations of Hall Thruster Plumes and Analysis for Realistic Spacecraft

  3. Comparison of Hall Thruster Plume Expansion Model with Experimental Data (Preprint)

    DTIC Science & Technology

    2006-07-01

    Cartesian mesh. AQUILA, the focus of this study, is a hybrid PIC model that tracks particles along an unstructured tetrahedral mesh. COLISEUM is capable...measurements of the ion current density profile, ion energy distributions, and ion species fraction distributions using a nude Faraday probe...Spacecraft and Rockets, Vol.37 No.1. 6 Oh, D. and Hastings, D., “Three Dimensional PIC -DSMC Simulations of Hall Thruster Plumes and Analysis for

  4. Monitoring of Injected CO2 at Geologic CO2 Storage Demonstration Sites with Significant Pressure Depletion and/or Re-Pressurization Histories

    NASA Astrophysics Data System (ADS)

    Saini, D.

    2016-12-01

    Majority of geologic CO2 storage sites for currently operated large-scale integrated carbon capture and storage projects (LSIPs) in operation around the world are depleted oil fields that have been undergone significant depletion and re-pressurization prior to injection of captured CO2. A better understanding of any of the implications associated with past depletion and re-pressurization histories to "out of injection zone" migration of injected CO2 can help in making monitoring strategies significantly more effective. Being the geologic CO2 storage demonstration sites for two most active LSIPs in the US, the West Hastings and the Bell Creek Oil Fields are the main focus of present study. The monitoring technologies that have been used/deployed/tested at both the normally pressured West Hastings and subnormally pressured Bell Creek storage sites appear to adequately address any of the potential "out of zone migration" of injected CO2 at these sites. It would be interesting to see if any of the collected monitoring data at the West Hastings and the Bell Creek storage sites could also be used in future to better understand the viability of initially subnormally pressured and subsequently depleted and re-pressurized oil fields as secure geologic CO2 storage sites with relatively large storage CO2 capacities compared to the depleted and re-pressurized oil fields that were initially discovered as normally pressured.

  5. MR imaging of focal lung lesions: elimination of flow and motion artifact by breath-hold ECG-gated and black-blood techniques on T2-weighted turbo SE and STIR sequences.

    PubMed

    Yamashita, Y; Yokoyama, T; Tomiguchi, S; Takahashi, M; Ando, M

    1999-05-01

    Respiratory and cardiac motion correction may result in better turbo spin-echo (SE) imaging of the lung. To compare breath-hold cardiac-gated black-blood T2-weighted turbo SE and turbo short-inversion-time inversion-recovery (STIR) magnetic resonance (MR) imaging pulse sequences with conventional breath-hold turbo SE and half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences for lesion conspicuity of focal lung lesions, 42 patients with focal lung lesions were prospectively studied with MR imaging at 1.5 T. Helical computed tomography was used as a reference. In comparison with the conventional breath-hold turbo SE sequence, all black-blood sequences had fewer image artifacts arising from the heart and blood flow. The overall image quality for the black-blood turbo SE and turbo STIR sequences was superior to that for the breath-hold turbo SE and HASTE sequence (P < 0.01). Not only focal lung lesions but also surrounding inflammatory changes were clearly visualized with these two sequences. With the HASTE sequence, although several slices could be obtained in one breath-hold, both the tumor and vessels appeared blurred. We conclude that T2-weighted turbo SE and turbo STIR imaging of the lung with effective suppression of flow and motion artifacts provide high-quality images in patients with focal lung lesions.

  6. Comparison of the kinetics of different Markov models for ligand binding under varying conditions

    SciTech Connect

    Martini, Johannes W. R.; Habeck, Michael

    2015-03-07

    We recently derived a Markov model for macromolecular ligand binding dynamics from few physical assumptions and showed that its stationary distribution is the grand canonical ensemble [J. W. R. Martini, M. Habeck, and M. Schlather, J. Math. Chem. 52, 665 (2014)]. The transition probabilities of the proposed Markov process define a particular Glauber dynamics and have some similarity to the Metropolis-Hastings algorithm. Here, we illustrate that this model is the stochastic analog of (pseudo) rate equations and the corresponding system of differential equations. Moreover, it can be viewed as a limiting case of general stochastic simulations of chemical kinetics. Thus, the model links stochastic and deterministic approaches as well as kinetics and equilibrium described by the grand canonical ensemble. We demonstrate that the family of transition matrices of our model, parameterized by temperature and ligand activity, generates ligand binding kinetics that respond to changes in these parameters in a qualitatively similar way as experimentally observed kinetics. In contrast, neither the Metropolis-Hastings algorithm nor the Glauber heat bath reflects changes in the external conditions correctly. Both converge rapidly to the stationary distribution, which is advantageous when the major interest is in the equilibrium state, but fail to describe the kinetics of ligand binding realistically. To simulate cellular processes that involve the reversible stochastic binding of multiple factors, our pseudo rate equation model should therefore be preferred to the Metropolis-Hastings algorithm and the Glauber heat bath, if the stationary distribution is not of only interest.

  7. Resistant starch reduces colonic and urinary p-cresol in rats fed a tyrosine-supplemented diet, whereas konjac mannan does not.

    PubMed

    Chen, Bixiao; Morioka, Sahya; Nakagawa, Tomoyuki; Hayakawa, Takashi

    2016-10-01

    The effect of resistant starch (RS) and konjac mannan (KM) to maintain and improve the large intestinal environment was compared. Wistar SPF rats were fed the following diets for 4 weeks: negative control diet (C diet), tyrosine-supplemented positive control diet (T diet), and luminacoid supplemented diets containing either high-molecular konjac mannan A (KMAT diet), low-molecular konjac mannan B (KMBT diet), high-amylose cornstarch (HAST diet), or heat-moisture-treated starch (HMTST diet). The luminacoid-fed group had an increased content of short-chain fatty acids in the cecum. HAS caused a significant decrease in p-cresol content in the cecum, whereas KM did not. Urinary p-cresol was reduced in the HAST group compared with the T group, but not the KM fed groups. Deterioration in the large intestinal environment was only improved completely in the HAST and HMTST groups, suggesting that RS is considerably more effective than KM in maintaining the large intestinal environment.

  8. Production of polyclonal antibody to a recombinant non-structural protein Nsp1a of human astrovirus.

    PubMed

    Liu, Chang; Liu, Wen-Hui; Kan, Li-Li; Li, Xin; Li, Yong-gang; Zhao, Wei

    2014-12-01

    Human astrovirus (HAstV) are important pathogens that cause acute viral diarrhea in infants. Little is known about the mechanisms of astrovirus-induced diarrhea. Previous studies have suggested that an apoptosis inducer may be encoded in the non-structural protein (nsP1a) of astrovirus and contribute to virus-induced diarrhea. To study the biological function of nsP1a and to gain further insight into nsP1a protein-host cell interactions, good quality antibodies must be produced. The nsP1agene of HAstV-1 was cloned into a bacterial expression vector Pgex-6P-1. The recombinant plasmid Pgex-6P-nsP1a was transformed into Escherichia coli BL21 (DE3) and expressed as a fusion protein that contains N-terminal GST tags. The expressed recombinant protein was purified and used as an antigen to produce an nsP1a antiserum in rabbits. ELISA was used to detect the titer of specific antibodies. Specificity activity was detected by Western blot and immunofluorescence analysis. The titer of specific antibodies was up to 1:30,000. Western blotting and immunofluorescence analysis indicated that the polyclonal antibody could recognize specifically the HAstV-1 nsP1a protein.

  9. The occurrence of hepatitis A and astroviruses in selected river and dam waters in South Africa.

    PubMed

    Taylor, M B; Cox, N; Vrey, M A; Grabow, W O

    2001-08-01

    Over a period of one year (June 1997-May 1998) samples of surface waters, used for domestic and recreational purposes, were collected weekly from the same sites on the Klip River and Vaal Dam, Gauteng, South Africa. Sensitive and specific reverse transcriptase-polymerase chain reaction-oligonucleotide probe assays were used to detect HAV and HAstV RNA in concentrates of the water and infectious virus in cell cultures infected with the water concentrates. HAV was detected in 18 (35.3%) of the river and 19 (37.3%) of the dam water samples, often in association with the RNA from other enteric viruses. HAstV was detected less frequently and was present in 11 (21.6%) of the river and 3 (5.9%) of the dam water samples. A seasonal pattern was noted for HAV but not for HAstV. Cell culture amplification in a variety of carefully selected cell culture systems enhanced the detection of both viruses. Infectious viruses were detected in dam water samples where microbiological indicators of faecal pollution were absent or within acceptable limits. The presence of these viruses in the dam and river water could pose a potential health risk for people using these waters for domestic or recreational purposes.

  10. Magnetic resonance imaging of pulmonary infection in immunocompromised children: comparison with multidetector computed tomography.

    PubMed

    Ozcan, H Nursun; Gormez, Ayşegul; Ozsurekci, Yasemin; Karakaya, Jale; Oguz, Berna; Unal, Sule; Cetin, Mualla; Ceyhan, Mehmet; Haliloglu, Mithat

    2017-02-01

    Computed tomography (CT) is commonly used to detect pulmonary infection in immunocompromised children. To compare MRI and multidetector CT findings of pulmonary abnormalities in immunocompromised children. Seventeen neutropaenic children (6 girls; ages 2-18 years) were included. Non-contrast-enhanced CT was performed with a 64-detector CT scanner. Axial and coronal non-enhanced thoracic MRI was performed using a 1.5-T scanner within 24 h of the CT examination (true fast imaging with steady-state free precession, fat-saturated T2-weighted turbo spin echo with motion correction, T2-weighted half-Fourier single-shot turbo spin echo [HASTE], fat-saturated T1-weighted spoiled gradient echo). Pulmonary abnormalities (nodules, consolidations, ground glass opacities, atelectasis, pleural effusion and lymph nodes) were evaluated and compared among MRI sequences and between MRI and CT. The relationship between MRI sequences and nodule sizes was examined by chi- square test. Of 256 CT lesions, 207 (81%, 95% confidence interval [CI] 76-85%) were detected at MRI. Of 202 CT-detected nodules, 157 (78%, 95% CI 71-83%) were seen at motion-corrected MRI. Of the 1-5-mm nodules, 69% were detected by motion-corrected T2-weighted MRI and 38% by HASTE MRI. Sensitivity of MRI (both axial fat-saturated T2-weighted turbo spin echo with variable phase encoding directions (BLADE) images and HASTE sequences) to detect pulmonary abnormalities is promising.

  11. Development of a multiplex PCR assay to detect gastroenteric pathogens in the feces of Mexican children.

    PubMed

    Tolentino-Ruiz, R; Montoya-Varela, D; García-Espitia, M; Salas-Benito, M; Gutiérrez-Escolano, A; Gómez-García, C; Figueroa-Arredondo, P; Salas-Benito, J; De Nova-Ocampo, M

    2012-10-01

    Acute gastroenteritis (AGE) is a major cause of childhood morbidity and mortality worldwide; the etiology of AGE includes viruses, bacteria, and parasites. A multiplex PCR assay to simultaneously identify human Astrovirus (HAstV), Calicivirus (HuCVs), Entamoeba histolytica (E. histolytica), and enteroinvasive Escherichia coli (EIEC) in stool samples is described. A total of 103 samples were individually analyzed by ELISA (enzyme-linked immunosorbent assays) and RT-PCR/PCR. HAstV and HuCVs were detected in four out of 103 samples (3.8 %) by RT-PCR, but ELISAs found only one sample as positive for HuCVs (2.5 %). E. histolytica was identified in two out of 19 samples (10.5 %) and EIEC in 13 out of 20 samples (70 %) by PCR, and all PCR products were sequenced to verify their identities. Our multiplex PCR results demonstrate the simultaneous amplification of different pathogens such as HAstV, EIEC, and E. histolytica in the same reaction, though the HuCVs signal was weak in every replicate. Regardless, this multiplex PCR protocol represents a novel tool for the identification of distinct pathogens and may provide support for the diagnosis of AGE in children.

  12. Molecular characterization and multiple infections of rotavirus, norovirus, sapovirus, astrovirus and adenovirus in outpatients with sporadic gastroenteritis in Shanghai, China, 2010-2011.

    PubMed

    Lu, Lijuan; Jia, Ran; Zhong, Huaqing; Xu, Menghua; Su, Liyun; Cao, Lingfeng; Dong, Zuoquan; Dong, Niuniu; Xu, Jin

    2015-05-01

    Rotavirus (RV), norovirus (NoV), sapovirus (SaV), human astrovirus (HAstV) and human adenovirus (HAdV) are significant because they are the most common pathogens that cause diarrhea in young children. The aim of this study was to investigate the genetic characteristics and compare the roles of these five viruses in outpatient children with diarrhea in Shanghai. A total of 436 fecal samples were collected from pediatric patients with acute gastroenteritis from January 2010 to December 2011. The selected samples were subjected to reverse transcription PCR (RT-PCR) or PCR to detect and genotype RV, NoV, SaV, HAstV and HAdV. RV (43.3 %, 189/436) was the most prevalent virus, followed by NoV (28.9 %, 126/436), HAdV (7.1 %, 31/436). HAstV (1.8 %, 8/436) and SaV (0.5 %, 2/436). The percentage of multiple infection cases was 14.9 % (65/436), and RV + NoV was the predominant mixed infection. The RV genotype combinations of P[8]G3 (52/189, 27.5 %), P[8]G1 (51/189, 26.9 %) and P[8]G9 (48/189, 25.4 %) occurred most frequently. The predominant NoV genotype was GII.4 (73.0 %, 92/126), and the majority of GII.4 clustered as GII.4-2006b (65.2 %, 60/92). Two of the SaV cases were identified as GI.2 and GII.1. All HAstV-positive samples belonged to HAstV-1. The predominant HAdV type was HAdV-41 (45.2 %, 14/31). This study clearly shows the diversity of the viral causative agents of acute gastroenteritis in outpatient children in Shanghai, which will provide baseline information for future vaccination strategies and development in this area.

  13. The Anatomy and Phylogenetic Relationships of “Pelorosaurus“ becklesii (Neosauropoda, Macronaria) from the Early Cretaceous of England

    PubMed Central

    Upchurch, Paul; Mannion, Philip D.; Taylor, Michael P.

    2015-01-01

    The sauropod dinosaur “Pelorosaurus” becklesii was named in 1852 on the basis of an associated left humerus, ulna, radius and skin impression from the Early Cretaceous (Berriasian-Valanginian) Hastings Beds Group, near Hastings, East Sussex, southeast England, United Kingdom. The taxonomy and nomenclature of this specimen have a complex history, but most recent workers have agreed that “P.” becklesii represents a distinct somphospondylan (or at least a titanosauriform) and is potentially the earliest titanosaur body fossil from Europe or even globally. The Hastings specimen is distinct from the approximately contemporaneous Pelorosaurus conybeari from Tilgate Forest, West Sussex. “P.” becklesii can be diagnosed on the basis of five autapomorphies, such as: a prominent anteriorly directed process projecting from the anteromedial corner of the distal humerus; the proximal end of the radius is widest anteroposteriorly along its lateral margin; and the unique combination of a robust ulna and slender radius. The new generic name Haestasaurus is therefore erected for “P.” becklesii. Three revised and six new fore limb characters (e.g. the presence/absence of condyle-like projections on the posterodistal margin of the radius) are discussed and added to three cladistic data sets for Sauropoda. Phylogenetic analysis confirms that Haestasaurus becklesii is a macronarian, but different data sets place this species either as a non-titanosauriform macronarian, or within a derived clade of titanosaurs that includes Malawisaurus and Saltasauridae. This uncertainty is probably caused by several factors, including the incompleteness of the Haestasaurus holotype and rampant homoplasy in fore limb characters. Haestasaurus most probably represents a basal macronarian that independently acquired the robust ulna, enlarged olecranon, and other states that have previously been regarded as synapomorphies of clades within Titanosauria. There is growing evidence that basal

  14. Can a T2 hyperintense rim sign differentiate uterine leiomyomas from other solid adnexal masses?

    PubMed

    Reiter, Michael J; Schwope, Ryan B; Lisanti, Christopher J; Banks, Nancy B

    2015-10-01

    To investigate the incidence of high T2 signal rims surrounding leiomyomas, evaluate if a particular T2-weighted sequence is more effective in depicting this rim, and determine if this sign is useful in differentiating pedunculated leiomyomas from other solid adnexal masses. In this retrospective study, two radiologists evaluated 233 T2 dark pelvic masses (223 uterine leiomyomas and 10 ovarian fibromas) in 60 women (mean age 47) on Magnetic resonance imaging for the presence of a high signal rim. Three different T2-weighted sequences were reviewed independently for uterine leiomyomas: half-Fourier acquisition single-shot turbo spin echo (HASTE), SPACE, and T2 with fat saturation (T2 FS). Only T2 FS images were available for 10 fibromas. A consensus review was conducted for discrepant cases. Statistical analyses were performed using Fisher's exact test, kappa test, and ANOVA RESULTS: For 223 uterine leiomyomas, 23% (95% CI 17.8-28.9%) demonstrated a high T2 signal rim sign on T2 FS compared with 4.9% (95% CI 2.6-8.9%) for HASTE and 6.7% (95% CI 3.9-11.1%) for SPACE. The difference between the number of positive rims on T2 FS relative-HASTE and SPACE was statistically significant (p < 0.001). For ovarian fibromas, 40% (95% CI 16.9-68.8%) were classified positive for a rim sign. A high T2 signal rim sign was present for up to 23% of uterine leiomyomas and the T2 FS sequence detected this rim sign most frequently. Up to 40% of ovarian fibromas can also have a T2 rim sign and, therefore, a solid adnexal mass with a T2 rim sign cannot be assumed to represent a pedunculated leiomyoma.

  15. A novel method of real-time reverse-transcription loop-mediated isothermal amplification developed for rapid and quantitative detection of human astrovirus.

    PubMed

    Wei, Haiyan; Zeng, Jing; Deng, Congliang; Zheng, Chengzhong; Zhang, Ximeng; Ma, Dan; Yi, Yong

    2013-03-01

    A one-step, real-time reverse-transcription loop-mediated isothermal amplification (rRT-LAMP) method targeting the 5' end of the capsid gene for rapid and quantitative detection of human astrovirus serotype 1 (HAstV 1) was developed. The assay is highly sensitive and comparable to real-time RT-PCR (rRT-PCR), with a detection limit of ∼100 RNA copies per assay. The specificity of the method was validated by the absence of any cross-reaction with RNA samples of HAstV 2-8 and other gastroenteritis viruses, followed by nucleotide sequencing of the amplified product. Fecal specimens (n=120) obtained from children under five years of age with gastroenteritis were tested by rRT-LAMP, rRT-PCR and transmission electron microscopy (TEM). Six (5%) of these samples were determined to be positive by both rRT-LAMP and rRT-PCR assay, and these two nucleic acid amplification methods resulted in a 200% increase in detection rates for HAstV infection compared with TEM alone. Furthermore, the rRT-LAMP assay is much more rapid than rRT-PCR and generates results in less than 20min for positive samples. The quantitation of viral load in stool specimens was determined from the standard curve plot of time-of-positivity versus initial RNA concentration. Most viral loads were determined to be within the range of 10(5)-10(8) copies. The results highlight the significance of the rapid rRT-LAMP method as a diagnostic and routine screening tool for the analysis of stool samples in hospital laboratories.

  16. Implementation and evaluation of a new workflow for registration and segmentation of pulmonary MRI data for regional lung perfusion assessment.

    PubMed

    Böttger, T; Grunewald, K; Schöbinger, M; Fink, C; Risse, F; Kauczor, H U; Meinzer, H P; Wolf, Ivo

    2007-03-07

    Recently it has been shown that regional lung perfusion can be assessed using time-resolved contrast-enhanced magnetic resonance (MR) imaging. Quantification of the perfusion images has been attempted, based on definition of small regions of interest (ROIs). Use of complete lung segmentations instead of ROIs could possibly increase quantification accuracy. Due to the low signal-to-noise ratio, automatic segmentation algorithms cannot be applied. On the other hand, manual segmentation of the lung tissue is very time consuming and can become inaccurate, as the borders of the lung to adjacent tissues are not always clearly visible. We propose a new workflow for semi-automatic segmentation of the lung from additionally acquired morphological HASTE MR images. First the lung is delineated semi-automatically in the HASTE image. Next the HASTE image is automatically registered with the perfusion images. Finally, the transformation resulting from the registration is used to align the lung segmentation from the morphological dataset with the perfusion images. We evaluated rigid, affine and locally elastic transformations, suitable optimizers and different implementations of mutual information (MI) metrics to determine the best possible registration algorithm. We located the shortcomings of the registration procedure and under which conditions automatic registration will succeed or fail. Segmentation results were evaluated using overlap and distance measures. Integration of the new workflow reduces the time needed for post-processing of the data, simplifies the perfusion quantification and reduces interobserver variability in the segmentation process. In addition, the matched morphological data set can be used to identify morphologic changes as the source for the perfusion abnormalities.

  17. Detection and Characterization of Waterborne Gastroenteritis Viruses in Urban Sewage and Sewage-Polluted River Waters in Caracas, Venezuela ▿

    PubMed Central

    Rodríguez-Díaz, J.; Querales, L.; Caraballo, L.; Vizzi, E.; Liprandi, F.; Takiff, H.; Betancourt, W. Q.

    2009-01-01

    The detection and molecular characterization of pathogenic human viruses in urban sewage have been used extensively to derive information on circulating viruses in given populations throughout the world. In this study, a similar approach was applied to provide an overview of the epidemiology of waterborne gastroenteritis viruses circulating in urban areas of Caracas, the capital city of Venezuela in South America. Dry season sampling was conducted in sewers and in a major river severely polluted with urban sewage discharges. Nested PCR was used for detection of human adenoviruses (HAds), while reverse transcription plus nested or seminested PCR was used for detection of enteroviruses (HuEVs), rotaviruses (HRVs), noroviruses (HuNoVs), and astroviruses (HAstVs). HRVs were fully characterized with genotype-specific primers for VP4 (genotype P), VP7 (genotype G), and the rotavirus nonstructural protein 4 (NSP4). HuNoVs and HAstVs were characterized by sequencing and phylogenetic analysis. The detection rates of all viruses were ≥50%, and all sampling events were positive for at least one of the pathogenic viruses studied. The predominant HRV types found were G1, P[8], P[4], and NSP4A and -B. Genogroup II of HuNoVs and HAstV type 8 were frequently detected in sewage and sewage-polluted river waters. This study reveals relevant epidemiological data on the distribution and persistence of human pathogenic viruses in sewage-polluted waters and addresses the potential health risks associated with transmission of these viruses through water-related environmental routes. PMID:19028907

  18. Detection and characterization of waterborne gastroenteritis viruses in urban sewage and sewage-polluted river waters in Caracas, Venezuela.

    PubMed

    Rodríguez-Díaz, J; Querales, L; Caraballo, L; Vizzi, E; Liprandi, F; Takiff, H; Betancourt, W Q

    2009-01-01

    The detection and molecular characterization of pathogenic human viruses in urban sewage have been used extensively to derive information on circulating viruses in given populations throughout the world. In this study, a similar approach was applied to provide an overview of the epidemiology of waterborne gastroenteritis viruses circulating in urban areas of Caracas, the capital city of Venezuela in South America. Dry season sampling was conducted in sewers and in a major river severely polluted with urban sewage discharges. Nested PCR was used for detection of human adenoviruses (HAds), while reverse transcription plus nested or seminested PCR was used for detection of enteroviruses (HuEVs), rotaviruses (HRVs), noroviruses (HuNoVs), and astroviruses (HAstVs). HRVs were fully characterized with genotype-specific primers for VP4 (genotype P), VP7 (genotype G), and the rotavirus nonstructural protein 4 (NSP4). HuNoVs and HAstVs were characterized by sequencing and phylogenetic analysis. The detection rates of all viruses were >or=50%, and all sampling events were positive for at least one of the pathogenic viruses studied. The predominant HRV types found were G1, P[8], P[4], and NSP4A and -B. Genogroup II of HuNoVs and HAstV type 8 were frequently detected in sewage and sewage-polluted river waters. This study reveals relevant epidemiological data on the distribution and persistence of human pathogenic viruses in sewage-polluted waters and addresses the potential health risks associated with transmission of these viruses through water-related environmental routes.

  19. Outage managment and health physics issue, 2008

    SciTech Connect

    Agnihotri, Newal

    2008-05-15

    The focus of the May-June issue is on outage management and health physics. Major articles include: Outage optimization initiatives, by George B. Beam, AREVA NP, Inc.; New plant based on excellent track records, by Jim Scarola, Progress Energy; Meeting customer needs and providing environmental benefits, by Peter S. Hastings, Duke Energy; Plants with 3-D design, by Jack A. Bailey, Tennessee Valley Authority; and Highest quality with exceptional planning, by Jason A. Walls, Duke Energy. Industry innovation articles include: Integrated exposure reduction plan, by Ed Wolfe, Exelon; Performance-based radiation worker training, by Joe Giuffre and Timothy Vriezerma, American Electric Power.

  20. Astrovirus Pathogenesis

    PubMed Central

    Johnson, Cydney; Hargest, Virginia; Cortez, Valerie; Meliopoulos, Victoria A.; Schultz-Cherry, Stacey

    2017-01-01

    Astroviruses are a major cause of diarrhea in the young, elderly, and the immunocompromised. Since the discovery of human astrovirus type 1 (HAstV-1) in 1975, the family Astroviridae has expanded to include two more human clades and numerous mammalian and avian-specific genotypes. Despite this, there is still little known about pathogenesis. The following review highlights the current knowledge of astrovirus pathogenesis, and outlines the critical steps needed to further astrovirus research, including the development of animal models of cell culture systems. PMID:28117758

  1. Markov Chain Monte Carlo Used in Parameter Inference of Magnetic Resonance Spectra

    DOE PAGES

    Hock, Kiel; Earle, Keith

    2016-02-06

    In this paper, we use Boltzmann statistics and the maximum likelihood distribution derived from Bayes’ Theorem to infer parameter values for a Pake Doublet Spectrum, a lineshape of historical significance and contemporary relevance for determining distances between interacting magnetic dipoles. A Metropolis Hastings Markov Chain Monte Carlo algorithm is implemented and designed to find the optimum parameter set and to estimate parameter uncertainties. In conclusion, the posterior distribution allows us to define a metric on parameter space that induces a geometry with negative curvature that affects the parameter uncertainty estimates, particularly for spectra with low signal to noise.

  2. Foreign Bodies in the Aerodigestive Tract

    PubMed Central

    Lawson, Victor G.; Middleton, William G.

    1986-01-01

    Foreign bodies in the aerodigestive tract are common. They may cause minimal disturbance of function, severe morbidity or even sudden death. They enter the aerodigestive tract because of haste during eating, disturbances in physical function, impairments due to extreme youth or age, or contamination of food with foreign bodies. Common symptoms are pain, dysphagia, odynophagia, cough, airway distress, hemoptysis and hematemesis. Signs include point tenderness, respiratory distress and surgical emphysema. Clinical, radiological and endoscopic investigations are described, as are principles of crisis and elective management. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9 PMID:21267132

  3. Spatial distribution of GRB and large scale structure of the Universe

    NASA Astrophysics Data System (ADS)

    Bagoly, Zsolt; Racz, Istvan; Gyorgy Balazs, Lajos; Toth, Viktor; Horvath, Istvan

    2015-08-01

    We studied the distribution the starburst galaxies from Millenium XXL database at z=0.82. First we examined the starburst distribution in the classical Millenium I, from the DeLucia (2006) database which used a semi-analytical model for the galaxies genesis. We found a relationship between the starburst galaxies and the dark matter density distribution in Millenium I and we determined the Millenium I and Millenium XXL transformation factor. We simulated a starburst galaxies sample with Markov Chain Monte Carlo method where we used the Metropolis-Hastings algorithm. The connection between the large scale structures homogenous and starburst groups distribution on a defined scale were checked too.

  4. A brief history of the introduction of generalized ensembles to Markov chain Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Berg, Bernd A.

    2017-03-01

    The most efficient weights for Markov chain Monte Carlo calculations of physical observables are not necessarily those of the canonical ensemble. Generalized ensembles, which do not exist in nature but can be simulated on computers, lead often to a much faster convergence. In particular, they have been used for simulations of first order phase transitions and for simulations of complex systems in which conflicting constraints lead to a rugged free energy landscape. Starting off with the Metropolis algorithm and Hastings' extension, I present a minireview which focuses on the explosive use of generalized ensembles in the early 1990s. Illustrations are given, which range from spin models to peptides.

  5. Ten Years Post Desert Storm: Has Assault Support Learned the Lessons of Task Force X-Ray?

    DTIC Science & Technology

    2001-04-01

    Blubaugh -2 Capt Schlieker/ Capt Larson -3 Capt Hastings/ 1Lt Milne -4 Capt Moss/ Capt McGee LtCol Doucette/Capt Chartier PAX: LtCol Maloney Maj Schwartz...1Lt Zube -4 Capt Rogers / Capt Walden -1 LtCol Pettine/ -2 Capt Ingram/ -3 Capt Quagge/ -4 Capt Hays/ -1 Capt Erickson/ Capt Jaeger -2 Capt McCormick/Maj...Canty, Jeremiah D., Lieutenant Colonel, USMC, Fifth Flight UH-1N Aircraft Commander HMLA-367, interview by author, 01 May 2001. Chartier , Kirk, Captain

  6. Diagnostic neuroradiology for the interventional neuroradiologist

    PubMed Central

    Pereira, Vitor Mendes; Vargas, Maria Isabel; Marcos, Ana; Bijlenga, Philippe; Narata, Ana Paula; Haller, Sven; Lövblad, Karl-Olof

    2013-01-01

    In order to further improve the impact of the continuously evolving neurointerventional techniques, the interventional neuroradiologist needs to have at his disposal more powerful techniques to image the central nervous system. With the recent development of diagnostics techniques that are computed tomography and magnetic resonance based we are now able to assess not just morphology, but also physiology, physiopathology and function. This review discusses the place of diagnostic techniques in the evaluation that the interventional neuroradiologist hast to make when confronted with patients. We provide an overview of current techniques for the brain and spine. PMID:24349643

  7. Norovirus diversity in diarrheic children from an African-descendant settlement in Belém, Northern Brazil.

    PubMed

    Aragão, Glicélia Cruz; Mascarenhas, Joana D'Arc Pereira; Kaiano, Jane Haruko Lima; de Lucena, Maria Silvia Sousa; Siqueira, Jones Anderson Monteiro; Fumian, Túlio Machado; Hernandez, Juliana das Mercês; de Oliveira, Consuelo Silva; Oliveira, Darleise de Souza; Araújo, Eliete da Cunha; Soares, Luana da Silva; Linhares, Alexandre Costa; Gabbay, Yvone Benchimol

    2013-01-01

    Norovirus (NoV), sapovirus (SaV) and human astrovirus (HAstV) are viral pathogens that are associated with outbreaks and sporadic cases of gastroenteritis. However, little is known about the occurrence of these pathogens in relatively isolated communities, such as the remnants of African-descendant villages ("Quilombola"). The objective of this study was the frequency determination of these viruses in children under 10 years, with and without gastroenteritis, from a "Quilombola" Community, Northern Brazil. A total of 159 stool samples were obtained from April/2008 to July/2010 and tested by an enzyme immunoassay (EIA) and reverse transcription-polymerase chain reaction (RT-PCR) to detect NoV, SaV and HAstV, and further molecular characterization was performed. These viruses were detected only in the diarrheic group. NoV was the most frequent viral agent detected (19.7%-16/81), followed by SaV (2.5%-2/81) and HAstV (1.2%-1/81). Of the 16 NoV-positive samples, 14 were sequenced with primers targeting the B region of the polymerase (ORF1) and the D region of the capsid (ORF2). The results showed a broad genetic diversity of NoV, with 12 strains being classified as GII-4 (5-41.7%), GII-6 (3-25%), GII-7 (2-16.7%), GII-17 (1-8.3%) and GI-2 (1-8.3%), as based on the polymerase region; 12 samples were classified, based on the capsid region, as GII-4 (6-50%, being 3-2006b variant and 3-2010 variant), GII-6 (3-25%), GII-17 (2-16.7%) and GII-20 (1-8.3%). One NoV-strain showed dual genotype specificity, based on the polymerase and capsid region (GII-7/GII-20). This study provides, for the first time, epidemiological and molecular information on the circulation of NoV, SaV and HAstV in African-descendant communities in Northern Brazil and identifies NoV genotypes that were different from those detected previously in studies conducted in the urban area of Belém. It remains to be determined why a broader NoV diversity was observed in such a semi-isolated community.

  8. Markov Chain Monte Carlo Used in Parameter Inference of Magnetic Resonance Spectra

    SciTech Connect

    Hock, Kiel; Earle, Keith

    2016-02-06

    In this paper, we use Boltzmann statistics and the maximum likelihood distribution derived from Bayes’ Theorem to infer parameter values for a Pake Doublet Spectrum, a lineshape of historical significance and contemporary relevance for determining distances between interacting magnetic dipoles. A Metropolis Hastings Markov Chain Monte Carlo algorithm is implemented and designed to find the optimum parameter set and to estimate parameter uncertainties. In conclusion, the posterior distribution allows us to define a metric on parameter space that induces a geometry with negative curvature that affects the parameter uncertainty estimates, particularly for spectra with low signal to noise.

  9. Coordination Compounds of Aluminum as Precursors to Aluminum Nitride

    DTIC Science & Technology

    1993-05-01

    ocoofii~ateale Al atoms chelooted end bridged by sn-al Upmhd. On Whe hasting , thene clustier speciesa tpateretly go oft o rofmn cor൱ntlned. Insoluble...ratio of El ,AI with eve y*tls a hyd~oeoabsionteals Poyer usmlsads on doorsmn~otiua which can be ined to ,~epaisi AIN Glovs by solution costing IdmAs by...polymuetheswooh tbocsghcondsnm- auttos teacthins involving the mnutirlla N-It and R-AI group on the perilpitry oft). delestr mol-kua. 1 he sittuctioeta

  10. [Discharge of very preterm infants from neonatology: check list].

    PubMed

    Arnaud, F

    2004-02-01

    Key elements of the check list for neonatal discharge include: discharge discussion with parents, relation with maternal and child welfare assistants and family practitioner, scheduling of follow-up visits, request for insurance coverage, parental presence allowance, special education allowance, debriefing with nurses and nurses providers, clinical and biological appraisal, discharge prescription. For a former extremely premature baby, going home - often after a long hospitalization and a variety of pathologic problems - must be prepared and should not be decided in haste, not only for the baby and his/her parents, but also. for the neonatal staff!

  11. Detection of a Ferromagnetic Microwire

    DTIC Science & Technology

    2012-09-01

    circular field components, defined as follows: 3 p p s , p p p p p p 0 , 0 , , 0p p p p p ss s , s s s s s s 0 , cos , sin , 0 , 0s s s s s...the DC anisotropy field Ha that fixes the direction of Mst in the material, the depolarization field (5) due to the body’s shape, and the external...time-dependent applied field. Note that in the absence of an ac magnetic field, there is no depolarization field, and so 0M Hast   under DC

  12. Feasibility Study for a Compact, Multi-Purpose Bioluminescence Detector

    DTIC Science & Technology

    1998-09-30

    Symposium on Bioluminescence and Chemiluminescence. Eds. JW Hastings, LJ Kricka and PE Stanley. John Wiley & Sons Ltd, Sussex, UK. pp. 159-164...Lowenstine, M.R. Bowlby , and D.P. Cook. (1993) A new large volume bioluminescence bathyphotometer with defined turbulence excitation. Deep Sea Res. 40...and PE Stanley. John Wiley & Sons Ltd, Sussex, UK. pp. 159-164. Makemson, J.C., N.R. Fulayfil, W.L. Landry, L.M. Van Ert, C.F. Wimpee, E.A. Widder

  13. A sampling strategy for high-dimensional spaces applied to free-form gravitational lensing

    NASA Astrophysics Data System (ADS)

    Lubini, Mario; Coles, Jonathan

    2012-10-01

    We present a novel proposal strategy for the Metropolis-Hastings algorithm designed to efficiently sample general convex polytopes in 100 or more dimensions. This improves upon previous sampling strategies used for free-form reconstruction of gravitational lenses, but is general enough to be applied to other fields. We have written a parallel implementation within the lens modelling framework GLASS. Testing shows that we are able to produce uniform uncorrelated random samples which are necessary for exploring the degeneracies inherent in lens reconstruction.

  14. City lights of London, England taken during Expedition Six

    NASA Image and Video Library

    2003-02-04

    ISS006-E-22939 (4 February 2003) --- City lights of London, England were captured with a digital still camera by one of the Expedition Six crewmembers on the International Space Station (ISS). This nighttime view of the British capital shows the city’;s urban density and infrastructure as highlighted by electrical lighting. Beyond lie isolated bright areas marking the numerous smaller cities and towns of the region and as far southeast as Hastings on the coast. London’;s two major airports, Heathrow and Gatwick, are visible to the south of the city.

  15. Eutrophication control and the fallacy of nitrogen removal

    SciTech Connect

    Sincero, A.P.

    1984-11-01

    There has been a great deal of controversy over the issue of nitrogen control from sewage treatment plants discharges to alleviate excessive algae growths in receiving bodies of water. Some of the controversy seems to have risen from a thorough misunderstanding of the microbiology involved in the utilization of nitrogen by microbes. In a haste to control eutrophication, some regulators have required the removal of nitrogen from the effluent of sewage treatment plants; e.g., the Patuxent Nitrogen Removal Policy of the State of Maryland.

  16. Exploring Posterior Distributions Using Markov Chains

    DTIC Science & Technology

    1992-01-01

    ibutio;. T I..... i~it c..... 1 Q ELECTE JUL23 1992 Dist U S , D A0 This document ha beon approsd for publc release and sa* its distribution Is unlimitd...uniform, and Hastings (1970) and explored further by Peskun (1973). dmrwal . a t disto n frewa, 1989)rmayTo dfin Hatins vesio ofthealgoith, lt Qbe t...that direction, van Dijk, H. K., 3. P. Ilop, and A. S . Louter (1978). An algorithm for the computation of posterior moments and densities using simple

  17. Early Pottery Making in Northern Coastal Peru. Part III: Mössbauer Study of Sicán Pottery

    NASA Astrophysics Data System (ADS)

    Shimada, I.; Häusler, W.; Hutzelmann, T.; Riederer, J.; Wagner, U.

    2003-09-01

    Sicán blackware from a 1000-year old elite tomb at Huaca Loro was characterised by neutron activation analysis, optical thin-section microscopy, X-ray diffraction and Mössbauer spectroscopy. A number of blackware fragments from the later site of Puerto Pobre (ca. AD 1460-1550) were included in the analysis for comparison and found to be of different origin. The black surface of the specimens from Huaca Loro is mostly due to carbon deposition during firing in a reducing environment. Part of the pottery was merely dried at temperatures below 400°C, perhaps because it was made in haste for funeral use.

  18. American surgical biographies.

    PubMed

    Rutkow, I M

    1987-12-01

    Finding adequate biographical data on a given surgeon can cause great difficulty because of the lack of a single source containing biographies of these people. This article provides short biographies of 15 American surgeons of the 18th, 19th, and early 20th centuries: Henry Jacob Bigelow, Joseph Decatur Bryant, Gurdon Buck, John Murray Carnochan, John Syng Dorsey, George Michael Edebohls, Christian Fenger, George Ryerson Fowler, Arpad Geza Charles Gerster, William Gibson, Frank Hastings Hamilton, William Tod Helmuth, Andrew Jackson Howe, Joseph Pancoast, and John Allan Wyeth.

  19. Next-Generation Sequencing for Diagnosis and Tailored Therapy: A Case Report of Astrovirus-Associated Progressive Encephalitis.

    PubMed

    Frémond, M-L; Pérot, P; Muth, E; Cros, G; Dumarest, M; Mahlaoui, N; Seilhean, D; Desguerre, I; Hébert, C; Corre-Catelin, N; Neven, B; Lecuit, M; Blanche, S; Picard, C; Eloit, M

    2015-09-01

    A boy with X-linked agammaglobulinemia experienced progressive global motor decline, cerebellar syndrome, and epilepsy. All standard polymerase chain reactions for neurotropic viruses were negative on cerebrospinal fluid and brain biopsy. Next-generation sequencing allowed fast identification of a new astrovirus strain (HAstV-VA1/HMO-C-PA), which led to tailor the patient's treatment, with encouraging clinical monitoring over 1 year. © The Author 2015. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. When Public Health Becomes Politicized.

    PubMed

    Lerner, Barron H

    2017-09-01

    Perhaps nothing symbolizes the current polarized political climate in the United States more than the world of public health. Public health schools and health departments are full of "true believers," people willing to crusade for any program designed to reduce morbidity and mortality. But in the "real world," proven programs and strategies-such as gun-control measures, universal vaccination, and improved traffic safety-are routinely thwarted. Why do critics oppose efforts to improve the public's health? History can provide some answers. © 2017 The Hastings Center.

  1. Patience.

    PubMed

    Akhtar, Salman

    2015-02-01

    Patience is a multifaceted phenomenon consisting of acceptance of inner and outer reality, absence of resentment, retention of hope, and capacity to wait for better times without restlessness and haste. It originates in the childhood advance from pleasure principle to reality principle, though the attainment of secure attachment, object constancy, and frustration tolerance also contribute to it. Psychopathology involving patience generally manifests as endless waiting or chronic hurrying. Both the normative and morbid trajectories of patience have implications for psychoanalytic technique, which are illustrated here with the help of clinical vignettes.

  2. LMC: Logarithmantic Monte Carlo

    NASA Astrophysics Data System (ADS)

    Mantz, Adam B.

    2017-06-01

    LMC is a Markov Chain Monte Carlo engine in Python that implements adaptive Metropolis-Hastings and slice sampling, as well as the affine-invariant method of Goodman & Weare, in a flexible framework. It can be used for simple problems, but the main use case is problems where expensive likelihood evaluations are provided by less flexible third-party software, which benefit from parallelization across many nodes at the sampling level. The parallel/adaptive methods use communication through MPI, or alternatively by writing/reading files, and mostly follow the approaches pioneered by CosmoMC (ascl:1106.025).

  3. Trans-dimensional geoacoustic inversion of wind-driven ambient noise.

    PubMed

    Quijano, Jorge E; Dosso, Stan E; Dettmer, Jan; Zurk, Lisa M; Siderius, Martin

    2013-01-01

    This letter applies trans-dimensional Bayesian geoacoustic inversion to quantify the uncertainty due to model selection when inverting bottom-loss data derived from wind-driven ambient-noise measurements. A partition model is used to represent the seabed, in which the number of layers, their thicknesses, and acoustic parameters are unknowns to be determined from the data. Exploration of the parameter space is implemented using the Metropolis-Hastings algorithm with parallel tempering, whereas jumps between parameterizations are controlled by a reversible-jump Markov chain Monte Carlo algorithm. Sediment uncertainty profiles from inversion of simulated and experimental data are presented.

  4. Experimental and numerical study of supersonic flow over two blunted wedges

    NASA Astrophysics Data System (ADS)

    Kotov, M. A.; Ruleva, L. B.; Solodovnikov, S. I.; Surzhikov, S. T.

    2017-02-01

    Shock-wave experiments with aerodynamic primitives in the form of a half wedge/double wedge with blunt edges are performed. Experimental studies were conducted using models, which are located at the exit of the supersonic nozzle of the hypersonic aerodynamic shock tube (HAST). Schlieren fragments of shock-wave formation over wedges were experimentally obtained. Calculations of the shock wave interactions over models carried out with the use of the authors’ computer codes. The predicted results and their comparison with experiment showed a satisfactory agreement.

  5. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Cellular Automaton Simulations for Target Waves in Excitable Media

    NASA Astrophysics Data System (ADS)

    Zhang, Li-Sheng; Deng, Min-Yi; Kong, Ling-Jiang; Liu, Mu-Ren; Tang, Guo-Ning

    2010-01-01

    Using the Greenberg-Hasting cellular automata model, we study the properties of target waves in excitable media under the no-flux boundary conditions. For the system has only one excited state, the computer simulation and analysis lead to the conclusions that, the number of refractory states does not influence the wave-front speed; the wave-front speed decreases as the excitation threshold increases and increases as the neighbor radius increases; the period of target waves is equal to the number of cell states; the excitation condition for target waves is that the wave-front speed must be bigger than half of the neighbor radius.

  6. Design Description Document for PLANIT System Enhancements

    DTIC Science & Technology

    1977-04-01

    OCZ, VFYED and vIOD terminal switches, indicators, display formats and modes of operation. 1.1 Iound Rules And Asgurmtjon, "he following conventions ...EOT. A-5 * .* * ’Ith any other interruptable switch action, the entire screen is saved indesndent of cursor position. ’his is a software convention ...34’ON-ROL vorT_" APPLICABLF r!HANG D RSZRr. HNG7 HASt_ L--95CF TO NORYAL RESUuT OLrl LTSSON I .fT;:.4 WAS LCGGj--D SAE AS FROM 2 to 3 ABOVE COFF

  7. Astrovirus Diagnostics

    PubMed Central

    Pérot, Philippe; Lecuit, Marc; Eloit, Marc

    2017-01-01

    Various methods exist to detect an astrovirus infection. Current methods include electron microscopy (EM), cell culture, immunoassays, polymerase chain reaction (PCR) and various other molecular approaches that can be applied in the context of diagnostic or in surveillance studies. With the advent of metagenomics, novel human astrovirus (HAstV) strains have been found in immunocompromised individuals in association with central nervous system (CNS) infections. This work reviews the past and current methods for astrovirus detection and their uses in both research laboratories and for medical diagnostic purposes. PMID:28085120

  8. MIL-STD-1760 Application Guidelines

    DTIC Science & Technology

    1991-09-01

    AD-A255 714 ASD-TR-91-5009 MIL-STD-1760 APPLICATION GUIDELINES Computing Devices Company Hastings, East Sussex, England Control Data Corporation DTIC...other data, is not to be regarded by implication, or otherwise in any manner construed, as licensing the holder, or any other person or corporation ...S) 182-80-18 ASD-TR-91-5009 6a NAME OF PERFORMINC ORGANIZATION 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION Contrcl Di~ta Corporation (if

  9. Bibliography on Cold Regions Science and Technology. Volume 35, Part 2

    DTIC Science & Technology

    1981-12-01

    technical development plans. Gulf of Alaska North hast Gulf of Alaska (Sale No 551. lower Cook Inlet tSale NobOI. Kodiak (Sale \\o62l Fiscal ...491. eng, 35^005 ücomorphological obsers ations at kangcidlugssuaq. East NobOI. Kodnk (Sale Nob;» Fiscal Year 1181...Sound (Sale No 57), St George Basin (Sale No.70l. Vorth Aleu- tian Shelf (Sale No.75f. Navann Basin (Sale No 83) Fiscal year 1481 (1480. 204p.. eng

  10. Benefit Paradox.

    PubMed

    Baruch, Jay

    2016-05-01

    I could have been more understanding, especially when police brought a man I'll call Mr. Atkins to the emergency room for depression and suicidal ideation. But it was 3:00 a.m. and the ER was a carnival of disease and discontent, a parade of drunk drivers and folks who practiced conflict resolution with knives and bullets. A patient well known for her drug abuse wasn't done yelling at me for refusing to write her a narcotic script when a nurse tweaked at my elbow to please come speak with Mr. Atkins, who was making a case to walk out. © 2016 The Hastings Center.

  11. Markov Chain Monte Carlo Inference of Parametric Dictionaries for Sparse Bayesian Approximations

    PubMed Central

    Chaspari, Theodora; Tsiartas, Andreas; Tsilifis, Panagiotis; Narayanan, Shrikanth

    2016-01-01

    Parametric dictionaries can increase the ability of sparse representations to meaningfully capture and interpret the underlying signal information, such as encountered in biomedical problems. Given a mapping function from the atom parameter space to the actual atoms, we propose a sparse Bayesian framework for learning the atom parameters, because of its ability to provide full posterior estimates, take uncertainty into account and generalize on unseen data. Inference is performed with Markov Chain Monte Carlo, that uses block sampling to generate the variables of the Bayesian problem. Since the parameterization of dictionary atoms results in posteriors that cannot be analytically computed, we use a Metropolis-Hastings-within-Gibbs framework, according to which variables with closed-form posteriors are generated with the Gibbs sampler, while the remaining ones with the Metropolis Hastings from appropriate candidate-generating densities. We further show that the corresponding Markov Chain is uniformly ergodic ensuring its convergence to a stationary distribution independently of the initial state. Results on synthetic data and real biomedical signals indicate that our approach offers advantages in terms of signal reconstruction compared to previously proposed Steepest Descent and Equiangular Tight Frame methods. This paper demonstrates the ability of Bayesian learning to generate parametric dictionaries that can reliably represent the exemplar data and provides the foundation towards inferring the entire variable set of the sparse approximation problem for signal denoising, adaptation and other applications. PMID:28649173

  12. AN AFFINE-INVARIANT SAMPLER FOR EXOPLANET FITTING AND DISCOVERY IN RADIAL VELOCITY DATA

    SciTech Connect

    Hou Fengji; Hogg, David W.; Goodman, Jonathan; Weare, Jonathan; Schwab, Christian

    2012-02-01

    Markov chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the nonlinear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. This new sampler has only one free parameter, and does not require much tuning for good performance, which is important for automatization. The autocorrelation time of this sampler is approximately the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. This novel sampler would be ideal for projects involving large data sets such as statistical investigations of planet distribution. The biggest obstacle to ensemble samplers is the existence of multiple local optima; we present a clustering technique to deal with local optima by clustering based on the likelihood of the walkers in the ensemble. We demonstrate the effectiveness of the sampler on real radial velocity data.

  13. Parallel tempering for strongly nonlinear geoacoustic inversion.

    PubMed

    Dosso, Stan E; Holland, Charles W; Sambridge, Malcolm

    2012-11-01

    This paper applies parallel tempering within a Bayesian formulation for strongly nonlinear geoacoustic inverse problems. Bayesian geoacoustic inversion consists of sampling the posterior probability density (PPD) of seabed parameters to estimate integral properties, such as marginal probability distributions, based on ocean acoustic data and prior information. This sampling is usually carried out using the Markov-chain Monte Carlo method of Metropolis-Hastings sampling. However, standard sampling methods can be very inefficient for strongly nonlinear problems involving multi-modal PPDs with the potential to miss important regions of the parameter space and to significantly underestimate parameter uncertainties. Parallel tempering achieves efficient/effective sampling of challenging parameter spaces with the ability to transition freely between multiple PPD modes by running parallel Markov chains at a series of increasing sampling temperatures with probabilistic interchanges between chains. The approach is illustrated for inversion of (simulated) acoustic reverberation data for which the PPD is highly multi-modal. While Metropolis-Hastings sampling gives poor results even with very large sample sizes, parallel tempering provides efficient, convergent sampling of the PPD. Methods to enhance the efficiency of parallel tempering are also considered.

  14. Effect of oxygen pressure on glycogen synthesis by rat-liver slices

    PubMed Central

    Figueroa, Enrique; Vallejos, Rodolfo; Pfeifer, Ariana; Kahler, Cecilia

    1966-01-01

    1. Glycogen synthesized by rat-liver slices 0·5mm. thick incubated at 1atm. oxygen pressure in Hastings medium with glucose was localized in the cells of the periphery of the slice. Cells of the interior of this slice do not synthesize glycogen. 2. Inner cells of thin slices (about 0·3mm. thick) can synthesize glycogen when such slices are incubated under the same conditions, but oxygen pressures higher than 1atm. are required if inner cells of slices 0·5mm. or more thick are to be able to synthesize glycogen. 3. Localization of newly synthesized glycogen in rat-liver slices incubated in Hastings medium with glucose does not depend on glucose concentration. 4. Calculation of the minimum oxygen pressure required to synthesize glycogen gives values between 0·09 and 0·17atm. 5. The advantages of high oxygen pressures for the study of the synthesis of glycogen and other compounds that require ATP are discussed. ImagesFig. 2.Fig. 5. PMID:5938650

  15. Structural Requirements of Astrovirus Virus-Like Particles Assembled in Insect Cells

    PubMed Central

    Caballero, Santiago; Guix, Susana; Ribes, Enric; Bosch, Albert; Pintó, Rosa M.

    2004-01-01

    Expression of the complete ORF2 of human astrovirus serotype 1 (HAstV-1) in the baculovirus system led to the formation of virus-like particles (VLPs) of around 38 nm. The same kind of VLPs were also obtained either with the expression of a truncated form of ORF2 lacking the first 70 amino acids (aa), or with the same truncated form in which those 70 aa were replaced by the green fluorescent protein. All three kinds of VLPs were equally recognized by an anti-HAstV-1 polyclonal antibody and by two monoclonal antibodies (MAbs; 8E7 and 5B7), indicating a nonessential role of those amino acids neither in the capsid assembly nor in the antigen structure. A second type of structure consisting of 16-nm ring-like units was observed in all of the cases, mostly after disassembling the 38-nm VLPs through the addition of EDTA. The removal of the EDTA and the addition of Mg2+ ions promoted the reassembly of the 38-nm VLPs. The nature of these 16-nm ring-like structures, capsomers or T = 1 VLPs, still remains unclear. Biochemical analysis revealed no differences between the 38-nm VLPs and the 16-nm structures, whereas antigenically, they shared the 8E7 MAb epitope but differed in the 5B7 MAb epitope, with the latter structures being more readily recognized. PMID:15542679

  16. Structural requirements of astrovirus virus-like particles assembled in insect cells.

    PubMed

    Caballero, Santiago; Guix, Susana; Ribes, Enric; Bosch, Albert; Pintó, Rosa M

    2004-12-01

    Expression of the complete ORF2 of human astrovirus serotype 1 (HAstV-1) in the baculovirus system led to the formation of virus-like particles (VLPs) of around 38 nm. The same kind of VLPs were also obtained either with the expression of a truncated form of ORF2 lacking the first 70 amino acids (aa), or with the same truncated form in which those 70 aa were replaced by the green fluorescent protein. All three kinds of VLPs were equally recognized by an anti-HAstV-1 polyclonal antibody and by two monoclonal antibodies (MAbs; 8E7 and 5B7), indicating a nonessential role of those amino acids neither in the capsid assembly nor in the antigen structure. A second type of structure consisting of 16-nm ring-like units was observed in all of the cases, mostly after disassembling the 38-nm VLPs through the addition of EDTA. The removal of the EDTA and the addition of Mg(2+) ions promoted the reassembly of the 38-nm VLPs. The nature of these 16-nm ring-like structures, capsomers or T = 1 VLPs, still remains unclear. Biochemical analysis revealed no differences between the 38-nm VLPs and the 16-nm structures, whereas antigenically, they shared the 8E7 MAb epitope but differed in the 5B7 MAb epitope, with the latter structures being more readily recognized.

  17. Inscribed matter as an energy-efficient means of communication with an extraterrestrial civilization.

    PubMed

    Rose, Christopher; Wright, Gregory

    2004-09-02

    It is well known that electromagnetic radiation-radio waves-can in principle be used to communicate over interstellar distances. By contrast, sending physical artefacts has seemed extravagantly wasteful of energy, and imagining human travel between the stars even more so. The key consideration in earlier work, however, was the perceived need for haste. If extraterrestrial civilizations existed within a few tens of light years, radio could be used for two-way communication on timescales comparable to human lifetimes (or at least the longevities of human institutions). Here we show that if haste is unimportant, sending messages inscribed on some material can be strikingly more energy efficient than communicating by electromagnetic waves. Because messages require protection from cosmic radiation and small messages could be difficult to find among the material clutter near a recipient, 'inscribed matter' is most effective for long archival messages (as opposed to potentially short "we exist" announcements). The results suggest that our initial contact with extraterrestrial civilizations may be more likely to occur through physical artefacts-essentially messages in a bottle-than via electromagnetic communication.

  18. Fitting complex population models by combining particle filters with Markov chain Monte Carlo.

    PubMed

    Knape, Jonas; de Valpine, Perry

    2012-02-01

    We show how a recent framework combining Markov chain Monte Carlo (MCMC) with particle filters (PFMCMC) may be used to estimate population state-space models. With the purpose of utilizing the strengths of each method, PFMCMC explores hidden states by particle filters, while process and observation parameters are estimated using an MCMC algorithm. PFMCMC is exemplified by analyzing time series data on a red kangaroo (Macropus rufus) population in New South Wales, Australia, using MCMC over model parameters based on an adaptive Metropolis-Hastings algorithm. We fit three population models to these data; a density-dependent logistic diffusion model with environmental variance, an unregulated stochastic exponential growth model, and a random-walk model. Bayes factors and posterior model probabilities show that there is little support for density dependence and that the random-walk model is the most parsimonious model. The particle filter Metropolis-Hastings algorithm is a brute-force method that may be used to fit a range of complex population models. Implementation is straightforward and less involved than standard MCMC for many models, and marginal densities for model selection can be obtained with little additional effort. The cost is mainly computational, resulting in long running times that may be improved by parallelizing the algorithm.

  19. Searching for efficient Markov chain Monte Carlo proposal kernels.

    PubMed

    Yang, Ziheng; Rodríguez, Carlos E

    2013-11-26

    Markov chain Monte Carlo (MCMC) or the Metropolis-Hastings algorithm is a simulation algorithm that has made modern Bayesian statistical inference possible. Nevertheless, the efficiency of different Metropolis-Hastings proposal kernels has rarely been studied except for the Gaussian proposal. Here we propose a unique class of Bactrian kernels, which avoid proposing values that are very close to the current value, and compare their efficiency with a number of proposals for simulating different target distributions, with efficiency measured by the asymptotic variance of a parameter estimate. The uniform kernel is found to be more efficient than the Gaussian kernel, whereas the Bactrian kernel is even better. When optimal scales are used for both, the Bactrian kernel is at least 50% more efficient than the Gaussian. Implementation in a Bayesian program for molecular clock dating confirms the general applicability of our results to generic MCMC algorithms. Our results refute a previous claim that all proposals had nearly identical performance and will prompt further research into efficient MCMC proposals.

  20. Markov Chain Monte Carlo Inference of Parametric Dictionaries for Sparse Bayesian Approximations.

    PubMed

    Chaspari, Theodora; Tsiartas, Andreas; Tsilifis, Panagiotis; Narayanan, Shrikanth

    2016-06-15

    Parametric dictionaries can increase the ability of sparse representations to meaningfully capture and interpret the underlying signal information, such as encountered in biomedical problems. Given a mapping function from the atom parameter space to the actual atoms, we propose a sparse Bayesian framework for learning the atom parameters, because of its ability to provide full posterior estimates, take uncertainty into account and generalize on unseen data. Inference is performed with Markov Chain Monte Carlo, that uses block sampling to generate the variables of the Bayesian problem. Since the parameterization of dictionary atoms results in posteriors that cannot be analytically computed, we use a Metropolis-Hastings-within-Gibbs framework, according to which variables with closed-form posteriors are generated with the Gibbs sampler, while the remaining ones with the Metropolis Hastings from appropriate candidate-generating densities. We further show that the corresponding Markov Chain is uniformly ergodic ensuring its convergence to a stationary distribution independently of the initial state. Results on synthetic data and real biomedical signals indicate that our approach offers advantages in terms of signal reconstruction compared to previously proposed Steepest Descent and Equiangular Tight Frame methods. This paper demonstrates the ability of Bayesian learning to generate parametric dictionaries that can reliably represent the exemplar data and provides the foundation towards inferring the entire variable set of the sparse approximation problem for signal denoising, adaptation and other applications.

  1. Genomic Justice and Imagined Communities.

    PubMed

    Schwartz-Marin, Ernesto

    2017-07-01

    In this issue of the Hastings Center Report, Maya Sabatello and Paul Appelbaum explore the assumptions about community embedded in the U.S. Precision Medicine Initiative, which aims to recruit donor-partners who reflect the United States' racial and ethnic diversity. As Sabatello and Appelbaum discuss, the initiative is like other national biobanking efforts in bringing to life an imagined genetic community in need of critical attention, and given the public-private forms of partnership at the heart of the PMI, such efforts could become avenues to deepen existing inequalities rather than to alleviate them. The notion of justice has underwritten debates about genomic medicine, informed consent, citizenship, benefit sharing, and profit making since the first national biobanking project emerged at the dawn of the twenty-first century. In a paradigmatic case, the creation, by an Icelandic company, of the deCODE genomic biobank opened up fierce debates about the proper relationship between public good and private gain and became the first global example of the economic and political implications that imagined genetic communities could have in our shared future. In Mexico, in 2001, the Icelandic case fueled a policy agenda to deal with global health justice and the prospects of a future market-based colonialism predicated on the intimate knowledge of DNA. © 2017 The Hastings Center.

  2. Markov chain Monte Carlo methods: an introductory example

    NASA Astrophysics Data System (ADS)

    Klauenberg, Katy; Elster, Clemens

    2016-02-01

    When the Guide to the Expression of Uncertainty in Measurement (GUM) and methods from its supplements are not applicable, the Bayesian approach may be a valid and welcome alternative. Evaluating the posterior distribution, estimates or uncertainties involved in Bayesian inferences often requires numerical methods to avoid high-dimensional integrations. Markov chain Monte Carlo (MCMC) sampling is such a method—powerful, flexible and widely applied. Here, a concise introduction is given, illustrated by a simple, typical example from metrology. The Metropolis-Hastings algorithm is the most basic and yet flexible MCMC method. Its underlying concepts are explained and the algorithm is given step by step. The few lines of software code required for its implementation invite interested readers to get started. Diagnostics to evaluate the performance and common algorithmic choices are illustrated to calibrate the Metropolis-Hastings algorithm for efficiency. Routine application of MCMC algorithms may be hindered currently by the difficulty to assess the convergence of MCMC output and thus to assure the validity of results. An example points to the importance of convergence and initiates discussion about advantages as well as areas of research. Available software tools are mentioned throughout.

  3. Use of MRI in Differentiation of Papillary Renal Cell Carcinoma Subtypes: Qualitative and Quantitative Analysis.

    PubMed

    Doshi, Ankur M; Ream, Justin M; Kierans, Andrea S; Bilbily, Matthew; Rusinek, Henry; Huang, William C; Chandarana, Hersh

    2016-03-01

    The purpose of this study was to determine whether qualitative and quantitative MRI feature analysis is useful for differentiating type 1 from type 2 papillary renal cell carcinoma (PRCC). This retrospective study included 21 type 1 and 17 type 2 PRCCs evaluated with preoperative MRI. Two radiologists independently evaluated various qualitative features, including signal intensity, heterogeneity, and margin. For the quantitative analysis, a radiology fellow and a medical student independently drew 3D volumes of interest over the entire tumor on T2-weighted HASTE images, apparent diffusion coefficient parametric maps, and nephrographic phase contrast-enhanced MR images to derive first-order texture metrics. Qualitative and quantitative features were compared between the groups. For both readers, qualitative features with greater frequency in type 2 PRCC included heterogeneous enhancement, indistinct margin, and T2 heterogeneity (all, p < 0.035). Indistinct margins and heterogeneous enhancement were independent predictors (AUC, 0.822). Quantitative analysis revealed that apparent diffusion coefficient, HASTE, and contrast-enhanced entropy were greater in type 2 PRCC (p < 0.05; AUC, 0.682-0.716). A combined quantitative and qualitative model had an AUC of 0.859. Qualitative features within the model had interreader concordance of 84-95%, and the quantitative data had intraclass coefficients of 0.873-0.961. Qualitative and quantitative features can help discriminate between type 1 and type 2 PRCC. Quantitative analysis may capture useful information that complements the qualitative appearance while benefiting from high interobserver agreement.

  4. An Affine-invariant Sampler for Exoplanet Fitting and Discovery in Radial Velocity Data

    NASA Astrophysics Data System (ADS)

    Hou, Fengji; Goodman, Jonathan; Hogg, David W.; Weare, Jonathan; Schwab, Christian

    2012-02-01

    Markov chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the nonlinear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. This new sampler has only one free parameter, and does not require much tuning for good performance, which is important for automatization. The autocorrelation time of this sampler is approximately the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. This novel sampler would be ideal for projects involving large data sets such as statistical investigations of planet distribution. The biggest obstacle to ensemble samplers is the existence of multiple local optima; we present a clustering technique to deal with local optima by clustering based on the likelihood of the walkers in the ensemble. We demonstrate the effectiveness of the sampler on real radial velocity data.

  5. Telos versus Praxis in Bioethics.

    PubMed

    Chambers, Tod S

    2016-09-01

    The authors of "A Conceptual Model for the Translation of Bioethics Research and Scholarship" argue that bioethics must respond to institutional pressures by demonstrating that it is having an impact in the world. Any impact, the authors observe, must be "informed" by the goals of the discipline of bioethics. The concept of bioethics as a discipline is central to their argument. They begin by citing an essay that Daniel Callahan wrote in the first issue of Hastings Center Studies. Callahan argued in this 1973 piece that bioethics had yet to attain the status of a discipline, and he lauded the freedom of being able to define a new discipline. Callahan's essay shares with Mathews and colleague's a peculiarity: neither ever defines what it means to refer to something as a "discipline." To define a discipline does mean attending to the intended end product of scholarly activity, so I concur with Mathews et al.'s focus on outcomes. But I am concerned that in their argument they confusingly entangle their understanding of an academic discipline's internal goals, its telos, with its potential to have an impact on the external world, its praxis. The confusion that this can bring exposes what I believe is a profound problem within bioethics, the discipline's peculiar and at times intellectually hazardous relationship with its institutional hosts. © 2016 The Hastings Center.

  6. Effect of High Temperature Storage in Vacuum, Air, and Humid Conditions on Degradation of Gold/Aluminum Wire Bonds in PEMs

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander

    2006-01-01

    Microcircuits encapsulated in three plastic package styles were stored in different environments at temperatures varying from 130 C to 225 C for up to 4,000 hours in some cases. To assess the effect of oxygen, the parts were aged at high temperatures in air and in vacuum chambers. The effect of humidity was evaluated during long-term highly accelerated temperature and humidity stress testing (HAST) at temperatures of 130 C and 150 C. High temperature storage testing of decapsulated microcircuits in air, vacuum, and HAST chambers was carried out to evaluate the role of molding compounds in the environmentally-induced degradation and failure of wire bonds (WB). This paper reports on accelerating factors of environment and molding compound on WB failures. It has been shown that all environments, including oxygen, moisture, and the presence of molding compounds reduce time-to-failures compared to unencapsulated devices in vacuum conditions. The mechanism of the environmental effect on KB degradation is discussed.

  7. Dynamic collision-induced dissociation of peptides in a quadrupole ion trap mass spectrometer.

    PubMed

    Collin, Olivier L; Beier, Matthias; Jackson, Glen P

    2007-07-15

    The fragmentation of natural peptides using dynamic collision-induced dissociation (DCID), a novel fragmentation method for quadrupole ion traps, is demonstrated. Using leucine enkephalin as a diagnostic molecule, the fragmentation efficiencies and energetics of DCID are compared with other methods of collisional activation in ion traps such as conventional on-resonance excitation and high-amplitude short-time excitation (HASTE). A typical fragmentation efficiency of approximately 20% is achieved for DCID, which is significantly lower than conventional CID (maximum near 80%). Tandem mass spectra of two other peptides, substance P and oxidized insulin alpha-chain, demonstrate that product ion spectra for DCID are comparable to conventional or HASTE CID. Because DCID achieves fragmentation during the standard mass acquisition scan, no extra time is necessary for on-resonance excitation or product ion collection, so analysis times are reduced by a minimum of 10-15% depending on the scanning conditions. DCID therefore offers more tandem mass spectra per second than conventional methods of collisional activation, which could be highly advantageous for bottom-up proteomics separations.

  8. Modeling the Sinoatrial Node by Cellular Automata with Irregular Topology

    NASA Astrophysics Data System (ADS)

    Makowiec, Danuta

    The role of irregularity in intercellular connections is studied in the first natural human pacemaker called the sinoatrial node by modeling with the Greenberg-Hastings cellular automata. Facts from modern physiology about the sinoatrial node drive modeling. Heterogeneity between cell connections is reproduced by a rewiring procedure applied to a square lattice. The Greenberg-Hastings rule, representing the intrinsic cellular dynamics, is modified to imitate self-excitation of each pacemaker cell. Moreover, interactions with nearest neighbors are changed to heterogeneous ones by enhancing horizontal connections. Stationary states of the modeled system emerge as self-organized robust oscillatory states. Since the sinoatrial node role relies on a single cell cyclic activity, properties of single cells are studied. It appears that the strength and diversity of cellular oscillations depend directly on properties of intrinsic cellular dynamics. But these oscillations also depend on the underlying topology. Moderate nonuniformity of intercellular connections are found vital for proper function of the sinoatrial node, namely, for producing robust oscillatory states that are able to respond effectively to the autonomic system control.

  9. GSFC_20170927_Archive_e001672

    NASA Image and Video Library

    2012-08-23

    This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more go to: http://1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  10. A fast and efficient Gibbs sampler for BayesB in whole-genome analyses.

    PubMed

    Cheng, Hao; Qu, Long; Garrick, Dorian J; Fernando, Rohan L

    2015-10-14

    In whole-genome analyses, the number p of marker covariates is often much larger than the number n of observations. Bayesian multiple regression models are widely used in genomic selection to address this problem of [Formula: see text] The primary difference between these models is the prior assumed for the effects of the covariates. Usually in the BayesB method, a Metropolis-Hastings (MH) algorithm is used to jointly sample the marker effect and the locus-specific variance, which may make BayesB computationally intensive. In this paper, we show how the Gibbs sampler without the MH algorithm can be used for the BayesB method. We consider three different versions of the Gibbs sampler to sample the marker effect and locus-specific variance for each locus. Among the Gibbs samplers that were considered, the most efficient sampler is about 2.1 times as efficient as the MH algorithm proposed by Meuwissen et al. and 1.7 times as efficient as that proposed by Habier et al. The three Gibbs samplers presented here were twice as efficient as Metropolis-Hastings samplers and gave virtually the same results.

  11. Ultra-thin atomic-layer deposited alumina incorporating silica sol makes ultra-durable antireflection coatings

    NASA Astrophysics Data System (ADS)

    Li, Jia; Lan, Pinjun; Xu, Hua; Zhang, Xianpeng; Yang, Ye; Tan, Ruiqin; Jylhä, Olli; Lu, Yuehui

    2012-11-01

    We propose a strategy to make soda-lime glass maintain both high transparency and long-term durability in stringent high temperature and humid environments. Experiments reveal that the double-layered coatings with 110-nm-thick SiO2 and ultra-thin 25-nm- or 50-nm-thick Al2O3 layers, prepared by sol-gel dip coating and atomic layer deposition (ALD), respectively, exhibit the improvement of 5.88-6.32% in Tave (the average transmittance from the wavelength of 400-700 nm), as compared with that of the bare glass. On the other hand, the highly accelerated temperature and humidity stress test (HAST) confirms that both samples can sustain the 180 h test without any proven transmittance degradation, while the normalized Tave of the bare glass drastically drops to 43.1% of the initial value after the 108 h HAST. It implies that the ultra-thin Al2O3 films prepared by ALD, followed by dip-coated low-index layers such as SiO2 or nanostructured layer, can achieve both higher average transmittance and better durability, which would be of significance for the applications of ALD and dip coating techniques in the fields of consumer electronics, architecture with glass facades, and photovoltaics.

  12. Non-enhanced magnetic resonance imaging of the small bowel at 7 Tesla in comparison to 1.5 Tesla: First steps towards clinical application.

    PubMed

    Hahnemann, Maria L; Kraff, Oliver; Maderwald, Stefan; Johst, Soeren; Orzada, Stephan; Umutlu, Lale; Ladd, Mark E; Quick, Harald H; Lauenstein, Thomas C

    2016-06-01

    To perform non-enhanced (NE) magnetic resonance imaging (MRI) of the small bowel at 7 Tesla (7T) and to compare it with 1.5 Tesla (1.5T). Twelve healthy subjects were prospectively examined using a 1.5T and 7T MRI system. Coronal and axial true fast imaging with steady-state precession (TrueFISP) imaging and a coronal T2-weighted (T2w) half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence were acquired. Image analysis was performed by 1) visual evaluation of tissue contrast and detail detectability, 2) measurement and calculation of contrast ratios and 3) assessment of artifacts. NE MRI of the small bowel at 7T was technically feasible. In the vast majority of the cases, tissue contrast and image details were equivalent at both field strengths. At 7T, two cases revealed better detail detectability in the TrueFISP, and better contrast in the HASTE. Susceptibility artifacts and B1 inhomogeneities were significantly increased at 7T. This study provides first insights into NE ultra-high field MRI of the small bowel and may be considered an important step towards high quality T2w abdominal imaging at 7T MRI. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Identification of a vacuolar proton channel that triggers the bioluminescent flash in dinoflagellates.

    PubMed

    Rodriguez, Juan D; Haq, Saddef; Bachvaroff, Tsvetan; Nowak, Kristine F; Nowak, Scott J; Morgan, Deri; Cherny, Vladimir V; Sapp, Maredith M; Bernstein, Steven; Bolt, Andrew; DeCoursey, Thomas E; Place, Allen R; Smith, Susan M E

    2017-01-01

    In 1972, J. Woodland Hastings and colleagues predicted the existence of a proton selective channel (HV1) that opens in response to depolarizing voltage across the vacuole membrane of bioluminescent dinoflagellates and conducts protons into specialized luminescence compartments (scintillons), thereby causing a pH drop that triggers light emission. HV1 channels were subsequently identified and demonstrated to have important functions in a multitude of eukaryotic cells. Here we report a predicted protein from Lingulodinium polyedrum that displays hallmark properties of bona fide HV1, including time-dependent opening with depolarization, perfect proton selectivity, and characteristic ΔpH dependent gating. Western blotting and fluorescence confocal microscopy of isolated L. polyedrum scintillons immunostained with antibody to LpHV1 confirm LpHV1's predicted organellar location. Proteomics analysis demonstrates that isolated scintillon preparations contain peptides that map to LpHV1. Finally, Zn2+ inhibits both LpHV1 proton current and the acid-induced flash in isolated scintillons. These results implicate LpHV1 as the voltage gated proton channel that triggers bioluminescence in L. polyedrum, confirming Hastings' hypothesis. The same channel likely mediates the action potential that communicates the signal along the tonoplast to the scintillon.

  14. Facts, values, and journalism.

    PubMed

    Gilbert, Susan

    2017-03-01

    At a time of fake news, hacks, leaks, and unverified reports, many people are unsure whom to believe. How can we communicate in ways that make individuals question their assumptions and learn? My colleagues at The Hastings Center and many journalists and scientists are grappling with this question and have, independently, reached the same first step: recognize that facts can't be fully understood without probing their connection to values. "Explaining the basics is important, of course, but we also need to diversify our approach to the coverage of science-particularly as it intersects with the matrix of cultural, religious, social, and political values of our readers," said an article in Undark, an online magazine of science journalism. An editorial in Nature called for scientists to engage directly with citizens in debates over climate change and genome editing, noting that "the ethical issues can be critically dependent on the science, for example, in understanding where the boundaries between non-heritable and heritable genome modifications might be." We're here to help. © 2017 The Hastings Center.

  15. Frontoparietal white matter integrity predicts haptic performance in chronic stroke.

    PubMed

    Borstad, Alexandra L; Choi, Seongjin; Schmalbrock, Petra; Nichols-Larsen, Deborah S

    2016-01-01

    Frontoparietal white matter supports information transfer between brain areas involved in complex haptic tasks such as somatosensory discrimination. The purpose of this study was to gain an understanding of the relationship between microstructural integrity of frontoparietal network white matter and haptic performance in persons with chronic stroke and to compare frontoparietal network integrity in participants with stroke and age matched control participants. Nineteen individuals with stroke and 16 controls participated. Haptic performance was quantified using the Hand Active Sensation Test (HASTe), an 18-item match-to-sample test of weight and texture discrimination. Three tesla MRI was used to obtain diffusion-weighted and high-resolution anatomical images of the whole brain. Probabilistic tractography was used to define 10 frontoparietal tracts total; Four intrahemispheric tracts measured bilaterally 1) thalamus to primary somatosensory cortex (T-S1), 2) thalamus to primary motor cortex (T-M1), 3) primary to secondary somatosensory cortex (S1 to SII) and 4) primary somatosensory cortex to middle frontal gyrus (S1 to MFG) and, 2 interhemispheric tracts; S1-S1 and precuneus interhemispheric. A control tract outside the network, the cuneus interhemispheric tract, was also examined. The diffusion metrics fractional anisotropy (FA), mean diffusivity (MD), axial (AD) and radial diffusivity (RD) were quantified for each tract. Diminished FA and elevated MD values are associated with poorer white matter integrity in chronic stroke. Nine of 10 tracts quantified in the frontoparietal network had diminished structural integrity poststroke compared to the controls. The precuneus interhemispheric tract was not significantly different between groups. Principle component analysis across all frontoparietal white matter tract MD values indicated a single factor explained 47% and 57% of the variance in tract mean diffusivity in stroke and control groups respectively. Age

  16. Frontoparietal white matter integrity predicts haptic performance in chronic stroke

    PubMed Central

    Borstad, Alexandra L.; Choi, Seongjin; Schmalbrock, Petra; Nichols-Larsen, Deborah S.

    2015-01-01

    Frontoparietal white matter supports information transfer between brain areas involved in complex haptic tasks such as somatosensory discrimination. The purpose of this study was to gain an understanding of the relationship between microstructural integrity of frontoparietal network white matter and haptic performance in persons with chronic stroke and to compare frontoparietal network integrity in participants with stroke and age matched control participants. Nineteen individuals with stroke and 16 controls participated. Haptic performance was quantified using the Hand Active Sensation Test (HASTe), an 18-item match-to-sample test of weight and texture discrimination. Three tesla MRI was used to obtain diffusion-weighted and high-resolution anatomical images of the whole brain. Probabilistic tractography was used to define 10 frontoparietal tracts total; Four intrahemispheric tracts measured bilaterally 1) thalamus to primary somatosensory cortex (T–S1), 2) thalamus to primary motor cortex (T–M1), 3) primary to secondary somatosensory cortex (S1 to SII) and 4) primary somatosensory cortex to middle frontal gyrus (S1 to MFG) and, 2 interhemispheric tracts; S1–S1 and precuneus interhemispheric. A control tract outside the network, the cuneus interhemispheric tract, was also examined. The diffusion metrics fractional anisotropy (FA), mean diffusivity (MD), axial (AD) and radial diffusivity (RD) were quantified for each tract. Diminished FA and elevated MD values are associated with poorer white matter integrity in chronic stroke. Nine of 10 tracts quantified in the frontoparietal network had diminished structural integrity poststroke compared to the controls. The precuneus interhemispheric tract was not significantly different between groups. Principle component analysis across all frontoparietal white matter tract MD values indicated a single factor explained 47% and 57% of the variance in tract mean diffusivity in stroke and control groups respectively. Age

  17. Hi'iaka: Haumea's Rapidly Spinning Moon

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-02-01

    An image from the Keck telescope of the dwarf planet Haumea (center) and its two moons, Hiiaka (above) and Namaka (below). [Caltech/Keck/Mike Brown]Recent observations of Hiiaka, the largest satellite of the dwarf planet Haumea, reveal that the moon is spinning much more rapidly than expected. What could this tell us about how Haumea and its moons formed?A Distant DwarfThe dwarf planet Haumea orbits beyond Neptune and has a mass of roughly 1/3 that of Pluto. Like Pluto, Haumea also has companions: two satellites of roughly 0.5% and 0.05% of Haumeas mass, orbiting at rather large distances of 36 and 70 Haumea radii (roughly 26,000 and 50,000 km).In a recently published study, a team led by Danielle Hastings (UC Los Angeles and Florida Institute of Technology) explored Hubble and Magellan observations of Hiiaka Haumeas larger, outer satellite to determine the rate at which it rotates on its axis.Hiiakas light curve, phase-folded at its most likely rotation period of 9.8 hours. The double peak is due to the fact that Hiiaka is likely not a spherical body, so it shows two maxima in brightness in each full rotation. [Hastings et al. 2016]Rapid RotationNominally, wed expect Hiiaka to be rotating synchronously its rotation period should be the same as its orbital period of 49.5 days. We expect this because the amount of time needed for tidal forces to despin Hiiaka to synchronous rotation should be much shorter than the time needed for these forces to produce Hiiakas observed low eccentricity and large semimajor axis.Therefore it was quite the surprise when Hastings and collaborators analyzed Hiiakas light curve and found that the moon revolves on its axis once every 9.8 hours! Thats roughly 120 times faster than the expected synchronous rate.Formation TheoriesWhat does this discovery reveal about Hiiakas formation? Hastings and collaborators propose three possible scenarios. They then use analytic calculations and numerical simulations to try to constrain them based on

  18. Prevalence and risk factors of needlestick injuries, sharps injuries, and blood and body fluid exposures among operating room nurses in Thailand.

    PubMed

    Kasatpibal, Nongyao; Whitney, JoAnne D; Katechanok, Sadubporn; Ngamsakulrat, Sukanya; Malairungsakul, Benjawan; Sirikulsathean, Pinyo; Nuntawinit, Chutatip; Muangnart, Thanisara

    2016-01-01

    Operating room nurses are at high risk for occupational exposure to bloodborne pathogens. This study examined the prevalence of and risk factors for needlestick injuries (NSIs), sharps injuries (SIs), and blood and body fluid exposures (BBFEs) among operating room nurses in Thai hospitals. A cross-sectional study was performed in 247 Thai hospitals. Questionnaires eliciting demographic data and information on injury occurrence and risk factors were distributed to 2500 operating room nurses, and 2031 usable questionnaires were returned, for a response rate of 81.2%. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using multiple logistic regression analysis. The prevalence of NSIs, SIs, and BBFEs was 23.7%, 9.8%, and 40.0%, respectively. Risk factors for NSIs were training without practice (OR, 1.67; 95% CI, 1.29-2.17), haste (OR, 4.81; 95% CI, 3.41-6.79), lack of awareness (OR, 1.36; 95% CI, 1.04-1.77), inadequate staffing (OR, 1.60; 95% CI, 1.21-2.11), and outdated guidelines (OR, 1.69; 95% CI, 1.04-2.74). One risk factor was identified for SIs: haste (OR, 2.43; 95% CI, 1.57-3.76). Risk factors for BBFEs were long working hours per week (OR, 2.07; 95% CI, 1.06-4.04), training without practice (OR, 1.55; 95% CI, 1.25-1.91), haste (OR, 1.66; 95% CI, 1.30-2.13), lack of awareness (OR, 1.54; 95% CI, 1.22-1.95), not wearing protective equipment (OR, 1.61; 95% CI, 1.26-2.06), and inadequate staffing (OR, 1.63; 95% CI, 1.26-2.11). This study highlights the high prevalence of NSIs, SIs, and BBFEs among Thai operating room nurses. Preventable risk factors were identified. Appropriate guidelines, adequate staffing, proper training, and self-awareness may reduce these occurrences. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. All rights reserved.

  19. DNA Microarray for Detection of Gastrointestinal Viruses

    PubMed Central

    Martínez, Miguel A.; Soto-del Río, María de los Dolores; Gutiérrez, Rosa María; Chiu, Charles Y.; Greninger, Alexander L.; Contreras, Juan Francisco; López, Susana; Arias, Carlos F.

    2014-01-01

    Gastroenteritis is a clinical illness of humans and other animals that is characterized by vomiting and diarrhea and caused by a variety of pathogens, including viruses. An increasing number of viral species have been associated with gastroenteritis or have been found in stool samples as new molecular tools have been developed. In this work, a DNA microarray capable in theory of parallel detection of more than 100 viral species was developed and tested. Initial validation was done with 10 different virus species, and an additional 5 species were validated using clinical samples. Detection limits of 1 × 103 virus particles of Human adenovirus C (HAdV), Human astrovirus (HAstV), and group A Rotavirus (RV-A) were established. Furthermore, when exogenous RNA was added, the limit for RV-A detection decreased by one log. In a small group of clinical samples from children with gastroenteritis (n = 76), the microarray detected at least one viral species in 92% of the samples. Single infection was identified in 63 samples (83%), and coinfection with more than one virus was identified in 7 samples (9%). The most abundant virus species were RV-A (58%), followed by Anellovirus (15.8%), HAstV (6.6%), HAdV (5.3%), Norwalk virus (6.6%), Human enterovirus (HEV) (9.2%), Human parechovirus (1.3%), Sapporo virus (1.3%), and Human bocavirus (1.3%). To further test the specificity and sensitivity of the microarray, the results were verified by reverse transcription-PCR (RT-PCR) detection of 5 gastrointestinal viruses. The RT-PCR assay detected a virus in 59 samples (78%). The microarray showed good performance for detection of RV-A, HAstV, and calicivirus, while the sensitivity for HAdV and HEV was low. Furthermore, some discrepancies in detection of mixed infections were observed and were addressed by reverse transcription-quantitative PCR (RT-qPCR) of the viruses involved. It was observed that differences in the amount of genetic material favored the detection of the most abundant

  20. Quantitative analysis of the breath-holding half-Fourier acquisition single-shot turbo spin-echo technique in abdominal MRI

    NASA Astrophysics Data System (ADS)

    Dong, Kyung-Rae; Goo, Eun-Hoe; Lee, Jae-Seung; Chung, Woon-Kwan

    2013-01-01

    A consecutive series of 50 patients (28 males and 22 females) who underwent hepatic magnetic resonance imaging (MRI) from August to December 2011 were enrolled in this study. The appropriate parameters for abdominal MRI scans were determined by comparing the images (TE = 90 and 128 msec) produced using the half-Fourier acquisition single-shot turbo spin-echo (HASTE) technique at different signal acquisition times. The patients consisted of 15 normal patients, 25 patients with a hepatoma and 10 patients with a hemangioma. The TE in a single patient was set to either 90 msec or 128 msec. This was followed by measurements using the four normal rendering methods of the biliary tract system and the background signal intensity using the maximal signal intensity techniques in the liver, spleen, pancreas, gallbladder, fat, muscles and hemangioma. The signal-to-noise and the contrast-to-noise ratios were obtained. The image quality was assessed subjectively, and the results were compared. The signal-to-noise and the contrast-to-noise ratios were significantly higher at TE = 128 msec than at TE = 90 when diseases of the liver, spleen, pancreas, gallbladder, and fat and muscles, hepatocellular carcinomas and hemangiomas, and rendering the hepatobiliary tract system based on the maximum signal intensity technique were involved (p < 0.05). In addition, the presence of artifacts, the image clarity and the overall image quality were excellent at TE = 128 msec (p < 0.05). In abdominal MRI, the breath-hold half-Fourier acquisition single-shot turbo spin-echo (HASTE) was found to be effective in illustrating the abdominal organs for TE = 128 msec. Overall, the image quality at TE = 128 msec was better than that at TE = 90 msec due to the improved signal-to-noise (SNR) and contrast-to-noise (CNR) ratios. Overall, the HASTE technique for abdominal MRI based on a high-magnetic field (3.0 T) at a TE of 128 msec can provide useful data.

  1. Construction of high-quality Caco-2 three-frame cDNA library and its application to yeast two-hybrid for the human astrovirus protein-protein interaction.

    PubMed

    Zhao, Wei; Li, Xin; Liu, Wen-Hui; Zhao, Jian; Jin, Yi-Ming; Sui, Ting-Ting

    2014-09-01

    Human epithelial colorectal adenocarcinoma (Caco-2) cells are widely used as an in vitro model of the human small intestinal mucosa. Caco-2 cells are host cells of the human astrovirus (HAstV) and other enteroviruses. High quality cDNA libraries are pertinent resources and critical tools for protein-protein interaction research, but are currently unavailable for Caco-2 cells. To construct a three-open reading frame, full length-expression cDNA library from the Caco-2 cell line for application to HAstV protein-protein interaction screening, total RNA was extracted from Caco-2 cells. The switching mechanism at the 5' end of the RNA transcript technique was used for cDNA synthesis. Double-stranded cDNA was digested by Sfi I and ligated to reconstruct a pGADT7-Sfi I three-frame vector. The ligation mixture was transformed into Escherichia coli HST08 premium electro cells by electroporation to construct the primary cDNA library. The library capacity was 1.0×10(6)clones. Gel electrophoresis results indicated that the fragments ranged from 0.5kb to 4.2kb. Randomly picked clones show that the recombination rate was 100%. The three-frame primary cDNA library plasmid mixture (5×10(5)cfu) was also transformed into E. coli HST08 premium electro cells, and all clones were harvested to amplify the cDNA library. To detect the sufficiency of the cDNA library, HAstV capsid protein as bait was screened and tested against the Caco-2 cDNA library by a yeast two-hybrid (Y2H) system. A total of 20 proteins were found to interact with the capsid protein. These results showed that a high-quality three-frame cDNA library from Caco-2 cells was successfully constructed. This library was efficient for the application to the Y2H system, and could be used for future research. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. DNA microarray for detection of gastrointestinal viruses.

    PubMed

    Martínez, Miguel A; Soto-Del Río, María de Los Dolores; Gutiérrez, Rosa María; Chiu, Charles Y; Greninger, Alexander L; Contreras, Juan Francisco; López, Susana; Arias, Carlos F; Isa, Pavel

    2015-01-01

    Gastroenteritis is a clinical illness of humans and other animals that is characterized by vomiting and diarrhea and caused by a variety of pathogens, including viruses. An increasing number of viral species have been associated with gastroenteritis or have been found in stool samples as new molecular tools have been developed. In this work, a DNA microarray capable in theory of parallel detection of more than 100 viral species was developed and tested. Initial validation was done with 10 different virus species, and an additional 5 species were validated using clinical samples. Detection limits of 1 × 10(3) virus particles of Human adenovirus C (HAdV), Human astrovirus (HAstV), and group A Rotavirus (RV-A) were established. Furthermore, when exogenous RNA was added, the limit for RV-A detection decreased by one log. In a small group of clinical samples from children with gastroenteritis (n = 76), the microarray detected at least one viral species in 92% of the samples. Single infection was identified in 63 samples (83%), and coinfection with more than one virus was identified in 7 samples (9%). The most abundant virus species were RV-A (58%), followed by Anellovirus (15.8%), HAstV (6.6%), HAdV (5.3%), Norwalk virus (6.6%), Human enterovirus (HEV) (9.2%), Human parechovirus (1.3%), Sapporo virus (1.3%), and Human bocavirus (1.3%). To further test the specificity and sensitivity of the microarray, the results were verified by reverse transcription-PCR (RT-PCR) detection of 5 gastrointestinal viruses. The RT-PCR assay detected a virus in 59 samples (78%). The microarray showed good performance for detection of RV-A, HAstV, and calicivirus, while the sensitivity for HAdV and HEV was low. Furthermore, some discrepancies in detection of mixed infections were observed and were addressed by reverse transcription-quantitative PCR (RT-qPCR) of the viruses involved. It was observed that differences in the amount of genetic material favored the detection of the most abundant

  3. Improving fitness of elite handball players: small-sided games vs. high-intensity intermittent training.

    PubMed

    Iacono, Antonio Dello; Eliakim, Alon; Meckel, Yoav

    2015-03-01

    The present study was designed to compare the effects of high-intensity intermittent training (HIIT) and small-sided games (SSGs) training on fitness variables of elite handball players. Eighteen highly trained players (mean age ± SD: 25.6 ± 0.5 years) were assigned to either HIIT or SSGs group training protocols twice per week for 8 weeks. The HIIT consisted of 12-24 × 15 seconds of high-intensity runs interspersed by 15 seconds of recovery. The SSGs training consisted of 3 against 3 small-sided handball games. Both training methods were matched for exercise duration and recovery at each training session. Before and after 8-week training, the following fitness variables were assessed-speed: 10- and 20-m sprint time, agility: handball agility specific test (HAST), upper arm strength: 1 repetition maximum (1RM) bench press test, lower limb power: counter-movement jump tests with (CMJarm) and without (CMJ) arm movement, and aerobic fitness (yo-yo intermittent recovery test level 1 [YYIRTL1]). Significant improvement was found in the YYIRTL1 (23.3 and 26.3%, respectively), 10-m sprint (2.3 and 4.1%, respectively) and 20-m sprint (2.1 and 4%, respectively), HAST (1.1 and 2.2%, respectively), 1RM bench press (6.8 and 12.3%, respectively), CMJ (7.4 and 10.8%, respectively), and CMJarm (6.4 and 8.9%, respectively) following training in both groups (p ≤ 0.05 for all). There was a significantly greater improvement in 10- and 20-m sprint, HAST, 1RM, CMJ, and CMJarm following the SSGs training compared with the HIIT (p ≤ 0.05 for all). These results indicated that both HIIT and SSGs are effective training methods for fitness development among elite adult handball players. However, SSGs training may be considered as the preferred training regimen for improving handball-specific fitness variables during the in-season period.

  4. Mid-Eocene alluvial-lacustrine succession at Gebel El-Goza El-Hamra (Shabrawet area, NE Eastern Desert, Egypt): Facies analysis, sequence stratigraphy and paleoclimatic implications

    NASA Astrophysics Data System (ADS)

    Wanas, H. A.; Sallam, E.; Zobaa, M. K.; Li, X.

    2015-11-01

    This study aims to provide the depositional facies, sequence stratigraphic and paleoclimatic characteristics of the Mid-Eocene (Bartonian) continental succession exposed at Gebel El-Goza El-Hamra (Shabrawet Area, NE Eastern Desert, Egypt). The studied succession consists of siliciclastic rocks followed upward by carbonate rocks. Detailed field observation and petrographic investigation indicate accumulation in floodplain-dominated alluvial and shallow lacustrine systems. The floodplain-dominated alluvial facies (45 m thick) is composed mainly of carbonate nodules-bearing, mottled mudrock with subordinate sandstone and conglomerate beds. The conglomerate and pebbly sandstone bodies interpreted as ephemeral braided channel deposits. The massive, laminated, planner cross-bedded, fine- to medium-grained sandstone bodies interlayered within mudstone reflect sheet flood deposits. The mudrocks associated with paleosols represent distal floodplain deposits. The shallow lacustrine facies (15 m thick) is made up of an alternation of marlstone, micritic limestone, dolostone and mudrock beds with charophytes and small gastropods. Both the alluvial and lacustrine facies show evidence of macro-and micro-pedogenic features. Pollen assemblages, stable δ18O and δ13C isotopes, and paleopedogenic features reflect prevalence of arid to semi-arid climatic conditions during the Bartonian. The sequence stratigraphic framework shows an overall fining-upward depositional sequence, consisting of Low- and High-accommodation Systems Tracts (LAST, HAST), and is bounded by two sequence boundaries (SB-1, SB-2). Conglomerate and pebbly sandstone deposits (braided channel and sheet flood deposits) of the lower part of the alluvial facies reflect a LAST. Mudrock and silty claystone facies (distal floodplain deposits) of the upper part of alluvial facies and its overlying lacustrine facies correspond to a HAST. The LAST, HAST and SB were formed during different accommodation-to-sediment supply (A

  5. Water-quality assessment of part of the Upper Mississippi River Basin Study Unit, Minnesota and Wisconsin- Nutrients, chlorophyll a, phytoplankton, and suspended sediment in streams, 1996-98

    USGS Publications Warehouse

    Kroening, Sharon E.; Lee, Kathy E.; Goldstein, R.M.

    2003-01-01

    The greatest chlorophyll-a concentrations and algal abundances generally were measured in the Little Cobb River near Beauford, Minnesota; Minnesota River near Jordan, Minnesota; Mississippi River at Hastings, Minnesota; and the Mississippi River at Red Wing, Minnesota. Greater concentrations and algal abundances at these sites may have been the result of increased nitrogen and phosphorus concentrations. Total phosphorus concentrations at these sites most frequently exceeded the goal of 0.1 mg/L set by the USEPA to prevent eutrophication. Phytoplankton communities at these sites primarily were dominated by blue-green algae during the summer of 1996. In contrast, at most of the other sites, the phytoplankton community was dominated by diatoms.

  6. Application of Thermo-Mechanical Measurements of Plastic Packages for Reliability Evaluation of PEMS

    NASA Technical Reports Server (NTRS)

    Sharma, Ashok K.; Teverovsky, Alexander

    2004-01-01

    Thermo-mechanical analysis (TMA) is typically employed for measurements of the glass transition temperature (Tg) and coefficients of thermal expansion (CTE) in molding compounds used in plastic encapsulated microcircuits (PEMs). Application of TMA measurements directly to PEMs allows anomalies to be revealed in deformation of packages with temperature, and thus indicates possible reliability concerns related to thermo-mechanical integrity and stability of the devices. In this work, temperature dependencies of package deformation were measured in several types of PEMs that failed environmental stress testing including temperature cycling, highly accelerated stress testing (HAST) in humid environments, and bum-in (BI) testing. Comparison of thermo-mechanical characteristics of packages and molding compounds in the failed parts allowed for explanation of the observed failures. The results indicate that TMA of plastic packages might be used for quality evaluation of PEMs intended for high-reliability applications.

  7. Semiparametric Bayesian inference on skew-normal joint modeling of multivariate longitudinal and survival data.

    PubMed

    Tang, An-Min; Tang, Nian-Sheng

    2015-02-28

    We propose a semiparametric multivariate skew-normal joint model for multivariate longitudinal and multivariate survival data. One main feature of the posited model is that we relax the commonly used normality assumption for random effects and within-subject error by using a centered Dirichlet process prior to specify the random effects distribution and using a multivariate skew-normal distribution to specify the within-subject error distribution and model trajectory functions of longitudinal responses semiparametrically. A Bayesian approach is proposed to simultaneously obtain Bayesian estimates of unknown parameters, random effects and nonparametric functions by combining the Gibbs sampler and the Metropolis-Hastings algorithm. Particularly, a Bayesian local influence approach is developed to assess the effect of minor perturbations to within-subject measurement error and random effects. Several simulation studies and an example are presented to illustrate the proposed methodologies.

  8. Where Shall We Go?

    PubMed

    Kaebnick, Gregory E

    2016-09-01

    This issue of the Hastings Center Report coincides with the annual conference of the American Society for Bioethics and Humanities, whose theme this year is "Where do we stand?" The issue addresses that theme with the article by Debra Mathews and colleagues and the set of brief response essays that follow it. Mathews et al., drawing on work carried out by the Association of Bioethics Program Directors, pose questions about how to understand and evaluate the worth of bioethics research. Those questions require them to think very broadly about what bioethics is, in the first place, and how it is related to medicine, health policy, science, and society generally. In short, they are thinking at the highest level about the question, where do we stand?

  9. Modeling association among demographic parameters in analysis of open population capture-recapture data

    USGS Publications Warehouse

    Link, William A.; Barker, Richard J.

    2005-01-01

    We present a hierarchical extension of the Cormack–Jolly–Seber (CJS) model for open population capture–recapture data. In addition to recaptures of marked animals, we model first captures of animals and losses on capture. The parameter set includes capture probabilities, survival rates, and birth rates. The survival rates and birth rates are treated as a random sample from a bivariate distribution, thus the model explicitly incorporates correlation in these demographic rates. A key feature of the model is that the likelihood function, which includes a CJS model factor, is expressed entirely in terms of identifiable parameters; losses on capture can be factored out of the model. Since the computational complexity of classical likelihood methods is prohibitive, we use Markov chain Monte Carlo in a Bayesian analysis. We describe an efficient candidate-generation scheme for Metropolis–Hastings sampling of CJS models and extensions. The procedure is illustrated using mark-recapture data for the moth Gonodontis bidentata.

  10. Optimal timing for managed relocation of species faced with climate change

    USGS Publications Warehouse

    McDonald Madden, Eve; Runge, Michael C.; Possingham, Hugh P.; Martin, Tara G.

    2011-01-01

    Managed relocation is a controversial climate-adaptation strategy to combat negative climate change impacts on biodiversity. While the scientific community debates the merits of managed relocation, species are already being moved to new areas predicted to be more suitable under climate change. To inform these moves, we construct a quantitative decision framework to evaluate the timing of relocation in the face of climate change. We find that the optimal timing depends on many factors, including the size of the population, the demographic costs of translocation and the expected carrying capacities over time in the source and destination habitats. In some settings, such as when a small population would benefit from time to grow before risking translocation losses, haste is ill advised. We also find that active adaptive management is valuable when the effect of climate change on source habitat is uncertain, and leads to delayed movement.

  11. Robustness of the Critical Behaviour in a Discrete Stochastic Reaction-Diffusion Medium

    NASA Astrophysics Data System (ADS)

    Fatès, Nazim; Berry, Hugues

    We study the steady states of a reaction-diffusion medium modelled by a stochastic 2D cellular automaton. We consider the Greenberg-Hastings model where noise and topological irregularities of the grid are taken into account. The decrease of the probability of excitation changes qualitatively the behaviour of the system from an "active" to an "extinct" steady state. Simulations show that this change occurs near a critical threshold; it is identified as a nonequilibrium phase transition which belongs to the directed percolation universality class. We test the robustness of the phenomenon by introducing persistent defects in the topology : directed percolation behaviour is conserved. Using experimental and analytical tools, we suggest that the critical threshold varies as the inverse of the average number of neighbours per cell.

  12. Finite element model updating of concrete structures based on imprecise probability

    NASA Astrophysics Data System (ADS)

    Biswal, S.; Ramaswamy, A.

    2017-09-01

    Imprecise probability based methods are developed in this study for the parameter estimation, in finite element model updating for concrete structures, when the measurements are imprecisely defined. Bayesian analysis using Metropolis Hastings algorithm for parameter estimation is generalized to incorporate the imprecision present in the prior distribution, in the likelihood function, and in the measured responses. Three different cases are considered (i) imprecision is present in the prior distribution and in the measurements only, (ii) imprecision is present in the parameters of the finite element model and in the measurement only, and (iii) imprecision is present in the prior distribution, in the parameters of the finite element model, and in the measurements. Procedures are also developed for integrating the imprecision in the parameters of the finite element model, in the finite element software Abaqus. The proposed methods are then verified against reinforced concrete beams and prestressed concrete beams tested in our laboratory as part of this study.

  13. Bayesian evidence computation for model selection in non-linear geoacoustic inference problems.

    PubMed

    Dettmer, Jan; Dosso, Stan E; Osler, John C

    2010-12-01

    This paper applies a general Bayesian inference approach, based on Bayesian evidence computation, to geoacoustic inversion of interface-wave dispersion data. Quantitative model selection is carried out by computing the evidence (normalizing constants) for several model parameterizations using annealed importance sampling. The resulting posterior probability density estimate is compared to estimates obtained from Metropolis-Hastings sampling to ensure consistent results. The approach is applied to invert interface-wave dispersion data collected on the Scotian Shelf, off the east coast of Canada for the sediment shear-wave velocity profile. Results are consistent with previous work on these data but extend the analysis to a rigorous approach including model selection and uncertainty analysis. The results are also consistent with core samples and seismic reflection measurements carried out in the area.

  14. Bayesian Inference for Duplication–Mutation with Complementarity Network Models

    PubMed Central

    Persing, Adam; Beskos, Alexandros; Heine, Kari; De Iorio, Maria

    2015-01-01

    Abstract We observe an undirected graph G without multiple edges and self-loops, which is to represent a protein–protein interaction (PPI) network. We assume that G evolved under the duplication–mutation with complementarity (DMC) model from a seed graph, G0, and we also observe the binary forest Γ that represents the duplication history of G. A posterior density for the DMC model parameters is established, and we outline a sampling strategy by which one can perform Bayesian inference; that sampling strategy employs a particle marginal Metropolis–Hastings (PMMH) algorithm. We test our methodology on numerical examples to demonstrate a high accuracy and precision in the inference of the DMC model's mutation and homodimerization parameters. PMID:26355682

  15. Applying diffusion-based Markov chain Monte Carlo

    PubMed Central

    Paul, Rajib; Berliner, L. Mark

    2017-01-01

    We examine the performance of a strategy for Markov chain Monte Carlo (MCMC) developed by simulating a discrete approximation to a stochastic differential equation (SDE). We refer to the approach as diffusion MCMC. A variety of motivations for the approach are reviewed in the context of Bayesian analysis. In particular, implementation of diffusion MCMC is very simple to set-up, even in the presence of nonlinear models and non-conjugate priors. Also, it requires comparatively little problem-specific tuning. We implement the algorithm and assess its performance for both a test case and a glaciological application. Our results demonstrate that in some settings, diffusion MCMC is a faster alternative to a general Metropolis-Hastings algorithm. PMID:28301529

  16. Dynamic range of hypercubic stochastic excitable media

    NASA Astrophysics Data System (ADS)

    Assis, Vladimir R. V.; Copelli, Mauro

    2008-01-01

    We study the response properties of d -dimensional hypercubic excitable networks to a stochastic stimulus. Each site, modeled either by a three-state stochastic susceptible-infected-recovered-susceptible system or by the probabilistic Greenberg-Hastings cellular automaton, is continuously and independently stimulated by an external Poisson rate h . The response function (mean density of active sites ρ versus h ) is obtained via simulations (for d=1,2,3,4 ) and mean-field approximations at the single-site and pair levels (∀d) . In any dimension, the dynamic range and sensitivity of the response function are maximized precisely at the nonequilibrium phase transition to self-sustained activity, in agreement with a reasoning recently proposed. Moreover, the maximum dynamic range attained at a given dimension d is a decreasing function of d .

  17. Hermeneutics and observation--a discussion.

    PubMed

    Nåden, Dagfinn

    2010-03-01

    This study deals with hermeneutics and observation. The purpose is to discuss some central concerns of hermeneutics in relation to observation as a research method. Attention is centred on the hermeneutic process, preunderstanding, understanding, sensitivity, the fore-conception of completeness and language. Examples from an observation study are presented. The study ends with a discussion of the importance of proceeding without haste and of silence in observational hermeneutic research. The researcher must allow oneself to be influenced by these qualities if the observations are to be undertaken in a hermeneutic spirit. Physical time must be of lesser importance than inner time. The possibility then exists for the researcher to wander the hermeneutic spiral to the greatest depth possible.

  18. Artificial Wombs and Abortion Rights.

    PubMed

    Cohen, I Glenn

    2017-07-01

    In a study published in late April in Nature Communications, the authors were able to sustain 105- to 115-day-old premature lamb fetuses-whose level of development was comparable to that of a twenty-three-week-old human fetus-for four weeks in an artificial womb, enabling the lambs to develop in a way that paralleled age-matched controls. The oldest lamb of the set, more than a year old at the time the paper came out, appeared completely normal. This kind of research brings us one step closer to providing excellent quality of life for premature newborns, but it also portends major legal and ethical questions, especially for abortion rights in America. © 2017 The Hastings Center.

  19. Cellular Automata Models of Ring Dynamics

    NASA Astrophysics Data System (ADS)

    Gravner, Janko

    This paper describes three models arising from the theory of excitable media, whose primary visual feature are expanding rings of excitation. Rigorous mathematical results and experimental/computational issues are both addressed. We start with the much-studied Greenberg-Hastings model (GHM) in which the rings are very short-lived, but they do have a transient percolation property. By contrast, in the model we call annihilating nested rings (ANR), excitation centers only gradually lose strength, i.e., each time they become inactive (and then stay so forever) with a fixed probability; we show how the long-term global connectivity properties of the set of excited sites undergo a phase transition. Second part of the paper is devoted to digital boiling (DB) in which new rings spontaneously appear at rested sites with a positive probability. We focus on such (related) issues as convergence to equilibrium, equilibrium excitation level and success of the basic coupling.

  20. Cellular automata models of ring dynamics

    SciTech Connect

    Gravner, J.

    1996-12-01

    This paper describes three models arising from the theory of excitable media, whose primary visual feature are expanding rings of excitation. Rigorous mathematical results and experimental/computational issues are both addressed. We start with the much-studied Greenberg-Hastings model (GHM) in which the rings are very short-lived, but they do have a transient percolation property. By contrast, in the model we call annihilating nested rings (ANR), excitation centers only gradually lose strength, i.e., each time they become inactive (and then stay so forever) with a fixed probability; we show how the long-term global connectivity properties of the set of excited sites undergo a phase transition. Second part of the paper is devoted to digital boiling (DB) in which new rings spontaneously appear at rested sites with a positive probability. We focus on such (related) issues as convergence to equilibrium, equilibrium excitation level and success of the basic coupling.

  1. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-09-27

    Dr. Robert Weems, emeritus paleontologist for the USGS verifies the recently discovered dinosaur track found on the NASA Goddard Space Flight Center campus. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: 1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  2. Bayesian phylogeny analysis via stochastic approximation Monte Carlo.

    PubMed

    Cheon, Sooyoung; Liang, Faming

    2009-11-01

    Monte Carlo methods have received much attention in the recent literature of phylogeny analysis. However, the conventional Markov chain Monte Carlo algorithms, such as the Metropolis-Hastings algorithm, tend to get trapped in a local mode in simulating from the posterior distribution of phylogenetic trees, rendering the inference ineffective. In this paper, we apply an advanced Monte Carlo algorithm, the stochastic approximation Monte Carlo algorithm, to Bayesian phylogeny analysis. Our method is compared with two popular Bayesian phylogeny software, BAMBE and MrBayes, on simulated and real datasets. The numerical results indicate that our method outperforms BAMBE and MrBayes. Among the three methods, SAMC produces the consensus trees which have the highest similarity to the true trees, and the model parameter estimates which have the smallest mean square errors, but costs the least CPU time.

  3. The neighborhood MCMC sampler for learning Bayesian networks

    NASA Astrophysics Data System (ADS)

    Alyami, Salem A.; Azad, A. K. M.; Keith, Jonathan M.

    2016-07-01

    Getting stuck in local maxima is a problem that arises while learning Bayesian networks (BNs) structures. In this paper, we studied a recently proposed Markov chain Monte Carlo (MCMC) sampler, called the Neighbourhood sampler (NS), and examined how efficiently it can sample BNs when local maxima are present. We assume that a posterior distribution f(N,E|D) has been defined, where D represents data relevant to the inference, N and E are the sets of nodes and directed edges, respectively. We illustrate the new approach by sampling from such a distribution, and inferring BNs. The simulations conducted in this paper show that the new learning approach substantially avoids getting stuck in local modes of the distribution, and achieves a more rapid rate of convergence, compared to other common algorithms e.g. the MCMC Metropolis-Hastings sampler.

  4. Bayesian Variable Selection on Model Spaces Constrained by Heredity Conditions.

    PubMed

    Taylor-Rodriguez, Daniel; Womack, Andrew; Bliznyuk, Nikolay

    2016-01-01

    This paper investigates Bayesian variable selection when there is a hierarchical dependence structure on the inclusion of predictors in the model. In particular, we study the type of dependence found in polynomial response surfaces of orders two and higher, whose model spaces are required to satisfy weak or strong heredity conditions. These conditions restrict the inclusion of higher-order terms depending upon the inclusion of lower-order parent terms. We develop classes of priors on the model space, investigate their theoretical and finite sample properties, and provide a Metropolis-Hastings algorithm for searching the space of models. The tools proposed allow fast and thorough exploration of model spaces that account for hierarchical polynomial structure in the predictors and provide control of the inclusion of false positives in high posterior probability models.

  5. Ripples: What to Expect When You Serve on a Bioethics Commission.

    PubMed

    Murray, Thomas H

    2017-05-01

    Cloning was the issue that put the National Bioethics Advisory Commission on the map, but the first clue that NBAC would address cloning was a terse fax from the White House to each of us who served on the Commission. The fax noted that with the birth of the sheep named Dolly, mammalian cloning was now a reality, and it tasked NBAC with providing advice on the ethics of human cloning and how the nation should respond to it. We were given ninety days to report our findings. That's a very tight deadline for a report written by a committee, but we met it, and along the way, I learned important lessons. My goal in this essay is to share what I learned at the ramparts of what I will call, with apologies to George Lucas, the Cloning Wars and through NBAC's work on five additional reports. © 2017 The Hastings Center.

  6. The first documented controlled trial in history.

    PubMed

    Koren, Gideon

    2015-01-01

     The first reported controlled human trial was conducted 2500 years ago by the Biblical judge Gideon Ben Yoash, who challenged God's Angel: "I will put a fleece of wool on the threshing floor. If there is dew on the fleece only, and it is dry on all the ground, then I will know that Thou wilt deliver Israel through me, as Thou hast spoken". In the control part of the trial he asked the Angel to keep the wool dry while the ground around it will be soaked with morning dew. It is unfortunate that these principles were not practiced for thousands of years thereafter, as many medical challenges could have been solved earlier.  

  7. Molecular dynamics simulations of field emission from a planar nanodiode

    SciTech Connect

    Torfason, Kristinn; Valfells, Agust; Manolescu, Andrei

    2015-03-15

    High resolution molecular dynamics simulations with full Coulomb interactions of electrons are used to investigate field emission in planar nanodiodes. The effects of space-charge and emitter radius are examined and compared to previous results concerning transition from Fowler-Nordheim to Child-Langmuir current [Y. Y. Lau, Y. Liu, and R. K. Parker, Phys. Plasmas 1, 2082 (1994) and Y. Feng and J. P. Verboncoeur, Phys. Plasmas 13, 073105 (2006)]. The Fowler-Nordheim law is used to determine the current density injected into the system and the Metropolis-Hastings algorithm to find a favourable point of emission on the emitter surface. A simple fluid like model is also developed and its results are in qualitative agreement with the simulations.

  8. Multiple imputation for high-dimensional mixed incomplete continuous and binary data.

    PubMed

    He, Ren; Belin, Thomas

    2014-06-15

    It is common in applied research to have large numbers of variables measured on a modest number of cases. Even with low rates of missingness of individual variables, such data sets can have a large number of incomplete cases with a mix of data types. Here, we propose a new joint modeling approach to address the high-dimensional incomplete data with a mix of continuous and binary data. Specifically, we propose a multivariate normal model encompassing both continuous variables and latent variables corresponding to binary variables. We apply a parameter-extended Metropolis–Hastings algorithm to generate the covariance matrix of a mixture of continuous and binary variables. We also introduce prior distribution families for unstructured covariance matrices to reduce the dimension of the parameter space. In several simulation settings, the method is compared with available-case analysis, a rounding method, and a sequential regression method.

  9. Spain: from the decree to the proposal.

    PubMed

    Gracia, Diego

    1987-06-01

    This is one in a series of four country reports published together in the Hastings Center Report. Gracia, a bioethicist, compares health care policy before and after Franco's dictatorship. Under Franco, compulsory health insurance was enacted, and modern hospitals were built at the expense of primary services. Patient care was governed by the principle of beneficence "in its extreme and paternalistic sense." Medicine in the democratic post-Franco period has reflected changes in Spanish society as political freedom has led to an increased moral pluralism and the formation of public policy through debate and compromise. Gracia identifies three bioethical issues where changes in attitudes and policies have been the greatest: resource allocation, abortion, and organ transplantation. He concludes his report by briefly describing the role bioethics plays in public policy formation in Spain today.

  10. Monte Carlo methods for light propagation in biological tissues.

    PubMed

    Vinckenbosch, Laura; Lacaux, Céline; Tindel, Samy; Thomassin, Magalie; Obara, Tiphaine

    2015-11-01

    Light propagation in turbid media is driven by the equation of radiative transfer. We give a formal probabilistic representation of its solution in the framework of biological tissues and we implement algorithms based on Monte Carlo methods in order to estimate the quantity of light that is received by a homogeneous tissue when emitted by an optic fiber. A variance reduction method is studied and implemented, as well as a Markov chain Monte Carlo method based on the Metropolis-Hastings algorithm. The resulting estimating methods are then compared to the so-called Wang-Prahl (or Wang) method. Finally, the formal representation allows to derive a non-linear optimization algorithm close to Levenberg-Marquardt that is used for the estimation of the scattering and absorption coefficients of the tissue from measurements.

  11. The first rite of passage: baptism in medieval memory.

    PubMed

    Deller, William S

    2011-01-01

    This article is part of a wider study that examines over 10,000 jurors' testimonies in proof-of-age hearings from 1246 to 1432, which were conducted to determine the legal majority of heirs-in-chief of the crown. It looks specifically at more than 1,500 references to the ceremony of baptism and tries to build up a picture of what the service was like in the memories of the participants. It reveals the haste and sometimes confusion of the preparations beforehand, the naming of infants, the role of godparents, the use of writing and the giving of gifts to record the birth, the celebrations that accompanied it, and details of the ceremonial itself, including the processions with lit torches and the crowds that often gathered. Despite the stereotypical nature of much testimony, it attempts to capture the atmosphere of what went on and what stuck in the minds of jurors.

  12. Reproductive technology: in the Netherlands, tolerance and debate.

    PubMed

    De Wachter, Maurice A M; De Wert, Guido MWR

    1987-06-01

    Two ethicists from the Netherlands' Institute for Bioethics file a report on their country in one of six Hastings Center Report articles on the status of reproductive technologies around the world. The situation in the Netherlands reflects the tolerant attitudes of the Dutch toward what are regarded as private matters. Artificial insemination, in vitro fertilization, and surrogate motherhood are available, and research on embryos is in the planning stages. Facilities offering reproductive services are regulated by the Minister of Health, with advice from the independent Health Council on Artificial Reproduction, the National Council for Public Health, and various insurance companies and professional medical organizations. Public policy debates center around such issues as the value of parenthood; involvement of third parties; secrecy about a child's genetic origins; privacy for semen, ovum, and embryo donors; access to services; and insurance coverage of treatment.

  13. Magnetic resonance imaging of acoustic streaming: absorption coefficient and acoustic field shape estimation.

    PubMed

    Madelin, Guillaume; Grucker, Daniel; Franconi, Jean-Michel; Thiaudiere, Eric

    2006-07-01

    In this study, magnetic resonance imaging (MRI) is used to visualize acoustic streaming in liquids. A single-shot spin echo sequence (HASTE) with a saturation band perpendicular to the acoustic beam permits the acquisition of an instantaneous image of the flow due to the application of ultrasound. An average acoustic streaming velocity can be estimated from the MR images, from which the ultrasonic absorption coefficient and the bulk viscosity of different glycerol-water mixtures can be deduced. In the same way, this MRI method could be used to assess the acoustic field and time-average power of ultrasonic transducers in water (or other liquids with known physical properties), after calibration of a geometrical parameter that is dependent on the experimental setup.

  14. Monopulse joint parameter estimation of multiple unresolved targets within the radar beam

    NASA Astrophysics Data System (ADS)

    Yuan, Hui; Wang, Chunyang; An, Lei; Li, Xin

    2017-06-01

    Aiming at the problem of the parameter estimation of multiple unresolved targets within the radar beam, using the joint bin processing model, a method of jointly estimating the number and the position of the targets is proposed based on reversible jump Markov Chain Monte Carlo (RJ-MCMC). Reasonable assumptions of the prior distributions and Bayesian theory are adopted to obtain the posterior probability density function of the estimated parameters from the conditional likelihood function of the observation, and then the acceptance ratios of the birth, death and update moves are given. During the update move, a hybrid Metropolis-Hastings (MH) sampling algorithm is used to make a better exploration of the parameter space. The simulation results show that this new method outperforms the method of ML-MLD [11] proposed by X.Zhang for similar estimation accuracy is achieved while fewer sub-pulses are needed.

  15. Adaptive Metropolis Sampling with Product Distributions

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Lee, Chiu Fan

    2005-01-01

    The Metropolis-Hastings (MH) algorithm is a way to sample a provided target distribution pi(z). It works by repeatedly sampling a separate proposal distribution T(x,x') to generate a random walk {x(t)}. We consider a modification of the MH algorithm in which T is dynamically updated during the walk. The update at time t uses the {x(t' less than t)} to estimate the product distribution that has the least Kullback-Leibler distance to pi. That estimate is the information-theoretically optimal mean-field approximation to pi. We demonstrate through computer experiments that our algorithm produces samples that are superior to those of the conventional MH algorithm.

  16. Unmet Needs, Unwanted Persons: A Call for Expansion of Safe Haven Laws.

    PubMed

    Bruce, Lori

    2016-09-01

    Legislative strategies for reducing infant abandonment and neonaticide developed in response to a series of sensational cases that occurred in Texas in 1999. The media coverage of these cases implied that the incidence of the crime was increasing, and Texas legislators responded with a law permitting parents to anonymously surrender their newborn at designated locations such as hospitals. This was the first "safe haven" law. Interest peaked nationwide, and by 2008 all states had a similar version of the law. These laws can trigger rapid cessation of parental rights and a fast-tracked adoption to a preapproved family, reflecting the legislators' assumption that it is better to permit struggling mothers to leave their children with well-intentioned strangers than to abandon the children or end their lives. These laws, however, suffer from several inadequacies. © 2016 The Hastings Center.

  17. SYSTEMIC TOXIC REACTIONS TO LOCAL ANESTHETICS

    PubMed Central

    Moore, Daniel C.; Green, John

    1956-01-01

    The topical use of anesthetic agents involves an element of risk. Systemic toxic reactions are rare, but they do occur and may result in death. When a reaction occurs from a topical application, it usually progresses rapidly to respiratory and cardiovascular collapse, and thus therapy must be instituted with more haste to avoid deaths. Fatal systemic toxic reactions from topically administered anesthetic drugs are, in effect, usually not due to well informed use of the drug but to misuse owing to less than complete understanding of absorption. Emphasis is placed on the causes, prophylaxis and treatment of severe systemic toxic reactions which follow the topical application of local anesthetic drugs. If systemic toxic reactions resulting from a safe dose of a local anesthetic agent are correctly treated, there will usually follow an uneventful recovery rather than a catastrophe. PMID:13343009

  18. Poland: biomedical ethics in a socialist state.

    PubMed

    Szawarski, Zbigniew

    1987-06-01

    In one of a Hastings Center Report series of four country reports, a professor of ethics discusses the Polish approach to ethical issues in health care. Szawarski begins by outlining five factors that influence the practice of medicine in Poland: a socialist form of government, the influence of the Roman Catholic Church, an ongoing economic crisis, the legacy of the Nazi death camps, and a lack of formal instruction in biomedical ethics. He then discusses three current ethical concerns of physicians, patients, and the public: regulation of physician conduct, abortion, and in vitro fertilization. There is little formal public debate of the issues, however, and physicians seem committed to upholding traditional medical codes of ethics without analyzing underlying moral principles and justifications.

  19. Lessons not yet learned from the Fukushima disaster

    NASA Astrophysics Data System (ADS)

    Klügel, Jens-Uwe

    2014-05-01

    The Fukushima nuclear catastrophe has led to a wide-spread international discussion on how seismic and tsunami hazards can be better predicted and adverse consequences be prevented.In some countries the event led to the complete phase-out of nuclear energy. The lessons drawn by different organisations including earth scientists, earthquake engineers,non-governmental and governmental organisations will be reviewed from an independent position. This review captures the following areas: 1) Hazard assessment 2) Engineering design and defense in depth concepts 3) Emergency preparedness It is shown that not all important lessons from the catastrophe have been drawn. Especially the need of an holistic approach towards hazard assessment and the implementation of defense in depth and diversity of design principles for critical infrastructures like nuclear power plants hast to be stronger emphasized to prevent similar disasters.

  20. Large-eddy simulation of flow around an airfoil on a structured mesh

    NASA Technical Reports Server (NTRS)

    Kaltenbach, Hans-Jakob; Choi, Haecheon

    1995-01-01

    The diversity of flow characteristics encountered in a flow over an airfoil near maximum lift taxes the presently available statistical turbulence models. This work describes our first attempt to apply the technique of large-eddy simulation to a flow of aeronautical interest. The challenge for this simulation comes from the high Reynolds number of the flow as well as the variety of flow regimes encountered, including a thin laminar boundary layer at the nose, transition, boundary layer growth under adverse pressure gradient, incipient separation near the trailing edge, and merging of two shear layers at the trailing edge. The flow configuration chosen is a NACA 4412 airfoil near maximum lift. The corresponding angle of attack was determined independently by Wadcock (1987) and Hastings & Williams (1984, 1987) to be close to 12 deg. The simulation matches the chord Reynolds number U(sub infinity)c/v = 1.64 x 10(exp 6) of Wadcock's experiment.

  1. A rare case of triple thyroid ectopia

    PubMed Central

    Rahalkar, Mukund; Rahalkar, Anand; Solav, Shrikant

    2014-01-01

    Various anomalies of thyro-glossal duct have been described, in which the duct may form a cyst or may present as a solid nodule to form an ectopic gland. The ectopic gland can develop along the tract of the duct to give rise to ectopic lingual, sublingual (pre-hyoid) or sub-hyoid (pyramidal) gland, with or without normal pre-tracheal thyroid gland.There are a few reports of double ectopia of thyroid but triple ectopia of thyroid is extremely rare. We have come across a case of triple thyroid ectopia, i.e., thyroid tissue at three locations along the tract of descent of thyro-glossal duct on CT, which hast been rarely reported in the world literature, and hence this report. PMID:24741526

  2. Replica state exchange metadynamics for improving the convergence of free energy estimates.

    PubMed

    Galvelis, Raimondas; Sugita, Yuji

    2015-07-15

    Metadynamics (MTD) is a powerful enhanced sampling method for systems with rugged energy landscapes. It constructs a bias potential in a predefined collective variable (CV) space to overcome barriers between metastable states. In bias-exchange MTD (BE-MTD), multiple replicas approximate the CV space by exchanging bias potentials (replica conditions) with the Metropolis-Hastings (MH) algorithm. We demonstrate that the replica-exchange rates and the convergence of free energy estimates of BE-MTD are improved by introducing the infinite swapping (IS) or the Suwa-Todo (ST) algorithms. Conceptually, IS and ST perform transitions in a replica state space rather than exchanges in a replica condition space. To emphasize this, the proposed scheme is called the replica state exchange MTD (RSE-MTD). Benchmarks were performed with alanine polypeptides in vacuum and water. For the systems tested in this work, there is no significant performance difference between IS and ST.

  3. Generalized Dynamic Factor Models for Mixed-Measurement Time Series

    PubMed Central

    Cui, Kai; Dunson, David B.

    2013-01-01

    In this article, we propose generalized Bayesian dynamic factor models for jointly modeling mixed-measurement time series. The framework allows mixed-scale measurements associated with each time series, with different measurements having different distributions in the exponential family conditionally on time-varying latent factor(s). Efficient Bayesian computational algorithms are developed for posterior inference on both the latent factors and model parameters, based on a Metropolis Hastings algorithm with adaptive proposals. The algorithm relies on a Greedy Density Kernel Approximation (GDKA) and parameter expansion with latent factor normalization. We tested the framework and algorithms in simulated studies and applied them to the analysis of intertwined credit and recovery risk for Moody’s rated firms from 1982–2008, illustrating the importance of jointly modeling mixed-measurement time series. The article has supplemental materials available online. PMID:24791133

  4. A Markov-Chain Monte-Carlo Based Method for Flaw Detection in Beams

    SciTech Connect

    Glaser, R E; Lee, C L; Nitao, J J; Hickling, T L; Hanley, W G

    2006-09-28

    A Bayesian inference methodology using a Markov Chain Monte Carlo (MCMC) sampling procedure is presented for estimating the parameters of computational structural models. This methodology combines prior information, measured data, and forward models to produce a posterior distribution for the system parameters of structural models that is most consistent with all available data. The MCMC procedure is based upon a Metropolis-Hastings algorithm that is shown to function effectively with noisy data, incomplete data sets, and mismatched computational nodes/measurement points. A series of numerical test cases based upon a cantilever beam is presented. The results demonstrate that the algorithm is able to estimate model parameters utilizing experimental data for the nodal displacements resulting from specified forces.

  5. The Theory and Practice of Surrogate Decision-Making.

    PubMed

    Wendler, David

    2017-01-01

    When a patient lacks decision-making capacity and has not left a clear advance directive, there is now widespread agreement that patient-designated and next-of-kin surrogates should implement substituted judgment within a process of shared decision-making. Specifically, after discussing the "best scientific evidence available, as well as the patient's values, goals, and preferences" with the patient's clinicians, the patient-designated or next-of-kin surrogate should attempt to determine what decision the patient would have made in the circumstances. To the extent that this approach works, it seems to provide about as much respect for the autonomy of incapacitated patients as we could ask for. But, as articles in this issue of the Report by Jeffrey Berger and by Ellen Robinson and colleagues emphasize, reality presents challenges. © 2017 The Hastings Center.

  6. Detection of spatially extended sources in high energy astrophysics with special application to lunar occultation

    NASA Astrophysics Data System (ADS)

    Jenke, Peter Alexander

    2009-01-01

    Occultation is a technique that enables image reconstruction and source identification with a non-imaging detector. Such an approach is well suited for a future survey mission in nuclear astrophysics. In particular, the Lunar Occultation Technique (LOT) utilizes the Moon as an occulting object and is the basis of a new gamma-ray survey mission concept, the Lunar OCcultation Observer (LOCO). Techniques utilizing the LOT to detect spatially extended emission, from the Galactic plane or Galactic Center region, have been developed. Given knowledge of detector position in lunar orbit, combined with lunar ephemeris and relevant coordinate transformations, occultation time series can be used to reconstruct skymaps of these extended Galactic emitters. Monte-Carlo Markov Chains (MCMC), incorporating the Metropolis-Hastings algorithm for parametric model testing, form the basis of the technique. Performance of the imaging methodology, and its application to nuclear astrophysics will be presented.

  7. Tail decay for the distribution of the endpoint of a directed polymer

    NASA Astrophysics Data System (ADS)

    Bothner, Thomas; Liechty, Karl

    2013-05-01

    We obtain an asymptotic expansion for the tails of the random variable { T}=\\arg\\max_{u\\in{R}}(A_2(u)-u^2) where A_2 is the Airy2 process. Using the formula of Schehr (2012 J. Stat. Phys. 149 385) that connects the density function of { T} to the Hastings-McLeod solution to the second Painlevé equation, we prove that as t → ∞, {P}(|{ T}|>t)=C\\rme^{-\\frac{4}{3}\\varphi(t)}t^{-145/32}(1+O(t^{-3/4})) , where φ(t) = t3 - 2t3/2 + 3t3/4, and the constant C is given explicitly.

  8. Understanding the agreements and controversies surrounding childhood psychopharmacology

    PubMed Central

    Parens, Erik; Johnston, Josephine

    2008-01-01

    The number of children in the US taking prescription drugs for emotional and behavioral disturbances is growing dramatically. This growth in the use of psychotropic drugs in pediatric populations has given rise to multiple controversies, ranging from concerns over off-label use and long-term safety to debates about the societal value and cultural meaning of pharmacological treatment of childhood behavioral and emotional disorders. This commentary summarizes the authors' eight main findings from the first of five workshops that seek to understand and produce descriptions of these controversies. The workshop series is convened by The Hastings Center, a bioethics research institute located in Garrison, New York, U.S.A. PMID:18261228

  9. Some social aspects of discovery, synthesis and production of cortisone in the 1930s-1950s.

    PubMed

    Jadreškić, Daria

    2016-12-01

    A discovery, synthesis and therapeutic application of cortisone present a paradigm for modern translational medicine (Hillier 2007, Saenger 2010), since they represented a joint achievement of discoveries by biochemists, Edward Calvin Kendall and Tadeus Reichstein; large scale synthesis by an industrial chemist, Lewis Hastings Sarett, and therapeutic application by a rheumatologist, Philip Showalter Hench. The goal of translational medicine is to speed up the process between basic research and clinical practice, and to integrate multiple disciplines in order to understand diverse outcomes (Zhang et al. 2014). In this paper conditions that made this basic/applied/clinical research interface possible will be presented: the rise of steroid chemistry, simultaneous individual accomplishments as well as continuous cooperation among scientists, military competitiveness, and cooperation among pharmaceutical companies.

  10. [Nutrition habits of students of University of Economics in Wroclaw].

    PubMed

    Kowalska, Anna

    2010-01-01

    The aim of a paper was an assessment of Wroclaw University of Economics students nutritional habits. Purposeful sample group selection was opted in this surrey. The method Ch2 was used to analyses questionnaire data. Obtained results confirm, that most of student don't nourish properly. Irregular breakfast before leaving home is the most frequent incorrectness, as well as irregular second breakfast or resignation from second breakfast at work or on classes breaks. Dinners consumption for large group of polled was irregular too. Lack of proper nutrition habits among young people is the cause of this state. Young people haste and limited finance causing that most of polled. Students consume only one course meal, mostly preparing by themselves. Basic foodstuffs i.e. meat, fishes, poultry, dairy products and fruits and vegetables or more often. Large group of students (especially women) declared eating sweets to often.

  11. Committees

    NASA Astrophysics Data System (ADS)

    Williams, Gwyn P.; Revesz, Peter; Arp, Uwe

    2014-03-01

    Conference Chairs NameOrganization Gwyn Williams Jefferson Lab Peter ReveszCornell High Energy Synchrotron Source Uwe ArpSynchrotron Ultraviolet Radiation Facility Programme Committee NameOrganization Alastair MacDowellAdvanced Light Source Tom ToellnerAdvanced Photon Source Amitava D RoyCenter for Advanced Microstructures and Devices Tom EllisCanadian Light Source Roberta SantarosaLaboratório Nacional de Luz Síncrotron Jerry (Jerome) HastingsLinac Coherent Light Source Steven HulbertNational Synchrotron Light Source Thomas A RabedeauStanford Synchrotron Radiation Lightsource Mark BissenSynchrotron Radiation Center Gwyn WilliamsJefferson Lab Peter ReveszCornell High Energy Synchrotron Source Uwe ArpSynchrotron Ultraviolet Radiation Facility

  12. Phase-Change Modelling in Severe Nuclear Accidents

    NASA Astrophysics Data System (ADS)

    Pain, Christopher; Pavlidis, Dimitrios; Xie, Zhihua; Percival, James; Gomes, Jefferson; Matar, Omar; Moatamedi, Moji; Tehrani, Ali; Jones, Alan; Smith, Paul

    2014-11-01

    This paper describes progress on a consistent approach for multi-phase flow modelling with phase-change. Although, the developed methods are general purpose the applications presented here cover core melt phenomena at the lower vessel head. These include corium pool formation, coolability and solidification. With respect to external cooling, comparison with the LIVE experiments (from Karlsruhe) is undertaken. Preliminary re-flooding simulation results are also presented. These include water injection into porous media (debris bed) and boiling. Numerical simulations follow IRSN's PEARL experimental programme on quenching/re-flooding. The authors wish to thank Prof. Timothy Haste of IRSN. Dr. D. Pavlidis is funded by EPSRC Consortium ``Computational Modelling for Advanced Nuclear Plants,'' Grant Number EP/I003010/1.

  13. Minding and Caring about Ethics in Brain Injury.

    PubMed

    Gillett, Grant

    2016-05-01

    Joseph Fins's book Rights Come to Mind: Brain Injury, Ethics, and the Struggle for Consciousness (Cambridge UP, 2015) is a considerable addition to the literature on disorders of consciousness and the murky area of minimally conscious states. Fins brings to this fraught area of clinical practice and neuroethical analysis a series of stories and reflections resulting in a pressing and sustained ethical challenge both to clinicians and to health care systems. The challenge is multifaceted, with diagnostic and therapeutic demands to be met by clinicians and a mix of moral, scientific-economic, and political resonances for health care analysts. Everything in the book resonates with my own clinical experience and the often messy and emotionally wrenching business of providing ongoing care for patients with severe brain injuries and disorders, people who frequently resist the categorizations that well-organized health care systems prefer and that can dictate terms of patient management. © 2016 The Hastings Center.

  14. Small Commercial Program DOE Project: Impact evaluation. Final report

    SciTech Connect

    Bathgate, R.; Faust, S.

    1992-08-12

    In 1991, Washington Electric Cooperative (WEC) implemented a Department of Energy grant to conduct a small commercial energy conservation project. The small commercial ``Mom, and Pop`` grocery stores within WEC`s service territory were selected as the target market for the project. Energy & Solid Waste Consultant`s (E&SWC) Impact Evaluation is documented here. The evaluation was based on data gathered from a variety of sources, including load profile metering, kWh submeters, elapsed time indicators, and billing histories. Five stores were selected to receive measures under this program: Waits River General Store, Joe`s Pond Store, Hastings Store, Walden General Store, and Adamant Cooperative. Specific measures installed in each store and description of each are included.

  15. Small Commercial Program DOE Project: Impact evaluation

    SciTech Connect

    Bathgate, R.; Faust, S. )

    1992-08-12

    In 1991, Washington Electric Cooperative (WEC) implemented a Department of Energy grant to conduct a small commercial energy conservation project. The small commercial Mom, and Pop'' grocery stores within WEC's service territory were selected as the target market for the project. Energy Solid Waste Consultant's (E SWC) Impact Evaluation is documented here. The evaluation was based on data gathered from a variety of sources, including load profile metering, kWh submeters, elapsed time indicators, and billing histories. Five stores were selected to receive measures under this program: Waits River General Store, Joe's Pond Store, Hastings Store, Walden General Store, and Adamant Cooperative. Specific measures installed in each store and description of each are included.

  16. Light cone matrix product

    SciTech Connect

    Hastings, Matthew B

    2009-01-01

    We show how to combine the light-cone and matrix product algorithms to simulate quantum systems far from equilibrium for long times. For the case of the XXZ spin chain at {Delta} = 0.5, we simulate to a time of {approx} 22.5. While part of the long simulation time is due to the use of the light-cone method, we also describe a modification of the infinite time-evolving bond decimation algorithm with improved numerical stability, and we describe how to incorporate symmetry into this algorithm. While statistical sampling error means that we are not yet able to make a definite statement, the behavior of the simulation at long times indicates the appearance of either 'revivals' in the order parameter as predicted by Hastings and Levitov (e-print arXiv:0806.4283) or of a distinct shoulder in the decay of the order parameter.

  17. Irreversible Markov chain Monte Carlo algorithm for self-avoiding walk

    NASA Astrophysics Data System (ADS)

    Hu, Hao; Chen, Xiaosong; Deng, Youjin

    2017-02-01

    We formulate an irreversible Markov chain Monte Carlo algorithm for the self-avoiding walk (SAW), which violates the detailed balance condition and satisfies the balance condition. Its performance improves significantly compared to that of the Berretti-Sokal algorithm, which is a variant of the Metropolis-Hastings method. The gained efficiency increases with spatial dimension (D), from approximately 10 times in 2D to approximately 40 times in 5D. We simulate the SAW on a 5D hypercubic lattice with periodic boundary conditions, for a linear system with a size up to L = 128, and confirm that as for the 5D Ising model, the finite-size scaling of the SAW is governed by renormalized exponents, v* = 2/ d and γ/ v* = d/2. The critical point is determined, which is approximately 8 times more precise than the best available estimate.

  18. Show Code.

    PubMed

    Shalev, Daniel

    2017-01-01

    "Let's get one thing straight: there is no such thing as a show code," my attending asserted, pausing for effect. "You either try to resuscitate, or you don't. None of this halfway junk." He spoke so loudly that the two off-service consultants huddled at computers at the end of the unit looked up… We did four rounds of compressions and pushed epinephrine twice. It was not a long code. We did good, strong compressions and coded this man in earnest until the end. Toward the final round, though, as I stepped up to do compressions, my attending looked at me in a deep way. It was a look in between willing me as some object under his command and revealing to me everything that lay within his brash, confident surface but could not be spoken. © 2017 The Hastings Center.

  19. Molecular dynamics simulations of field emission from a planar nanodiode

    NASA Astrophysics Data System (ADS)

    Torfason, Kristinn; Valfells, Agust; Manolescu, Andrei

    2015-03-01

    High resolution molecular dynamics simulations with full Coulomb interactions of electrons are used to investigate field emission in planar nanodiodes. The effects of space-charge and emitter radius are examined and compared to previous results concerning transition from Fowler-Nordheim to Child-Langmuir current [Y. Y. Lau, Y. Liu, and R. K. Parker, Phys. Plasmas 1, 2082 (1994) and Y. Feng and J. P. Verboncoeur, Phys. Plasmas 13, 073105 (2006)]. The Fowler-Nordheim law is used to determine the current density injected into the system and the Metropolis-Hastings algorithm to find a favourable point of emission on the emitter surface. A simple fluid like model is also developed and its results are in qualitative agreement with the simulations.

  20. Bayesian Variable Selection on Model Spaces Constrained by Heredity Conditions

    PubMed Central

    Taylor-Rodriguez, Daniel; Womack, Andrew; Bliznyuk, Nikolay

    2016-01-01

    This paper investigates Bayesian variable selection when there is a hierarchical dependence structure on the inclusion of predictors in the model. In particular, we study the type of dependence found in polynomial response surfaces of orders two and higher, whose model spaces are required to satisfy weak or strong heredity conditions. These conditions restrict the inclusion of higher-order terms depending upon the inclusion of lower-order parent terms. We develop classes of priors on the model space, investigate their theoretical and finite sample properties, and provide a Metropolis-Hastings algorithm for searching the space of models. The tools proposed allow fast and thorough exploration of model spaces that account for hierarchical polynomial structure in the predictors and provide control of the inclusion of false positives in high posterior probability models. PMID:28082825

  1. Sampling schemes and parameter estimation for nonlinear Bernoulli-Gaussian sparse models

    NASA Astrophysics Data System (ADS)

    Boudineau, Mégane; Carfantan, Hervé; Bourguignon, Sébastien; Bazot, Michael

    2016-06-01

    We address the sparse approximation problem in the case where the data are approximated by the linear combination of a small number of elementary signals, each of these signals depending non-linearly on additional parameters. Sparsity is explicitly expressed through a Bernoulli-Gaussian hierarchical model in a Bayesian framework. Posterior mean estimates are computed using Markov Chain Monte-Carlo algorithms. We generalize the partially marginalized Gibbs sampler proposed in the linear case in [1], and build an hybrid Hastings-within-Gibbs algorithm in order to account for the nonlinear parameters. All model parameters are then estimated in an unsupervised procedure. The resulting method is evaluated on a sparse spectral analysis problem. It is shown to converge more efficiently than the classical joint estimation procedure, with only a slight increase of the computational cost per iteration, consequently reducing the global cost of the estimation procedure.

  2. Cellular Automata Model of Cardiac Pacemaker

    NASA Astrophysics Data System (ADS)

    Makowiec, D.

    2008-05-01

    A network of Greenberg-Hasting cellular automata with cyclic intrinsic dynamics F rightarrow R rightarrow A rightarrow F rightarrow ... is shown to be a reliable approximation to the cardiac pacemaker. The three possible cell's states F, R, A are characterized by fixed timings { nF, nR, nA } -- time steps spent in each state. Dynamical properties of a simple line network are found to be critical with respect to the relation between nF and nR. The properties of a network arisen from a square lattice where some edges are rewired (locally and with the preference to link to cells which are more connected to other cells) are also studied. The resulted system evolves rhythmically with the period determined by timings. The emergence of a small group of neighboring automata where the whole system activity initiates is observed. The dominant evolution is accompanied with other rhythms, characterized by longer periods.

  3. Wave Optics in Discrete Excitable Media

    NASA Astrophysics Data System (ADS)

    Gu, Guo-Feng; Wei, Hai-Ming; Tang, Guo-Ning

    2012-05-01

    Refraction and reflection of planar waves in a discrete excitable medium is numerically investigated by using the Greenberg—Hasting model. It is found that the medium is anisotropic because the speed of the planar wave depends on the excitability of the medium and the direction of wave propagation. The reflection, diffraction, refraction, double refraction and delayed refraction are observed by using the correct choice of model parameters. When the incident angle is larger than the critical angle, the reflection, which is a back refraction, takes place. The reflection angle changes with the incident angle. The refraction in certain situations obeys Snell's law. Also, our results demonstrate that the incident, refracted and reflected waves can have different periods. The reflected and refracted waves can disappear.

  4. Religious voices in biotechnology: the case of gene patenting.

    PubMed

    Hanson, M J

    1999-01-01

    On 18 May 1995, nearly 200 religious leaders joined with leading biotechnology critic Jeremy Rifkin in a press conference named the "Joint Appeal against Human and Animal Patenting," a move that many within the biotechnology industry could only interpret as seeking to inhibit biotechnological advance. What moral and religious concerns motivated this challenge to patenting? How could the biotechnology industry understand and respectfully attend to these concerns? What values were at play in the debates that followed the joint appeal? What lessons for future dialogue can be learned from attempts at conversation between the opposing positions? This essay is a report from a Hastings Center research project that accepted the task of addressing these questions. Specifically, the project focused on the patenting of human genetic material, a subset of the issues raised by the joint appeal.

  5. GSFC_20170927_Archive_e001666

    NASA Image and Video Library

    2012-08-23

    Dr. Robert Weems, emeritus paleontologist for the USGS verifies the recently discovered dinosaur track found on the NASA Goddard Space Flight Center campus. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: http://1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  6. GSFC_20170927_Archive_e001665

    NASA Image and Video Library

    2012-08-23

    Dr. Robert Weems, emeritus paleontologist for the USGS verifies the recently discovered dinosaur track found on the NASA Goddard Space Flight Center campus. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: http://1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  7. GSFC_20170927_Archive_e001667

    NASA Image and Video Library

    2012-08-23

    Dr. Robert Weems, emeritus paleontologist for the USGS verifies the recently discovered dinosaur track found on the NASA Goddard Space Flight Center campus. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: http://1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  8. GSFC_20170927_Archive_e001670

    NASA Image and Video Library

    2012-08-23

    Dr. Robert Weems, emeritus paleontologist for the USGS verifies the recently discovered dinosaur track found on the NASA Goddard Space Flight Center campus. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: http://1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  9. GSFC_20170927_Archive_e001687

    NASA Image and Video Library

    2012-08-23

    Dr. Robert Weems, emeritus paleontologist for the USGS verifies the recently discovered dinosaur track found on the NASA Goddard Space Flight Center campus. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: http://1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  10. Genes, race, and the ethics of belief.

    PubMed

    Anomaly, Jonathan

    2014-09-01

    A Troublesome Inheritance, by Nicholas Wade, should be read by anyone interested in race and recent human evolution. Wade deserves credit for challenging the popular dog-ma that biological differences between groups either don't exist or cannot ex-plain the relative success of different groups at different tasks. Wade's work should be read alongside another re-cent book, The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, by Gregory Cochran and Henry Harpending. Together, these books represent a ma-jor turning point in the public debate about the speed with which relatively isolated groups can evolve: both books suggest that small genetic differences between members of different groups can have large impacts on their abilities and propensities, which in turn affect the outcomes of the societies in which they live. © 2014 by The Hastings Center.

  11. Militant morality: civil disobedience and bioethics.

    PubMed

    Cohen, C

    1989-01-01

    Seven essays in this issue of the Hastings Center Report defend civil disobedience as a legitimate form of protest against terrible injustices: legalized abortion (G. Leber); abridgement of women's reproductive rights (S. Davis); government policy toward persons with AIDS (H. Spiers and A. Novick); abuse of the rights of animals (S. Siegel, C. Jackson, and P. Singer). An eighth essay, by B. Nathanson, examines the motivations of Operation Rescue, an organization that uses civil disobedience to protest legalized abortion. Cohen explores the problems that these authors and others encounter in trying to justify deliberately breaking the law in public conscientious protest. He examines three forms of protest -- direct civil disobedience, indirect civil disobedience, and direct action -- and three justifications -- higher-law, utilitarian, and only possible means. Cohen concludes that, in a democracy, objective justification of civil disobedience is very difficult.

  12. No cheers for temporary artificial hearts.

    PubMed

    Annas, G J

    1985-10-01

    The author continues his argument against the temporary artificial heart ("The Phoenix heart: what we have to lose," Hastings Center Report 1985 Jun; 15(3): 15-16) with an account of recipient Michael Drummond's experience at the University of Arizona in August 1985. Annas faults the University's informed consent procedure and labels its consent form "misleading, rudimentary, and confusing." He also questions why Drummond was assigned top priority for a human heart after he had received a temporary artificial one. Annas urges a moratorium on permanent artificial hearts because of their devastating effects on recipients, and on temporary devices because they may become permanent. He also argues that there is, as yet, no ethically acceptable way of allocating human hearts to those with artificial hearts, and that the expensive bridge-to-transplant procedure fails to increase the total number of lives saved by heart transplants.

  13. Stable schemes for dissipative particle dynamics with conserved energy

    NASA Astrophysics Data System (ADS)

    Stoltz, Gabriel

    2017-07-01

    This article presents a new numerical scheme for the discretization of dissipative particle dynamics with conserved energy. The key idea is to reduce elementary pairwise stochastic dynamics (either fluctuation/dissipation or thermal conduction) to effective single-variable dynamics, and to approximate the solution of these dynamics with one step of a Metropolis-Hastings algorithm. This ensures by construction that no negative internal energies are encountered during the simulation, and hence allows to increase the admissible timesteps to integrate the dynamics, even for systems with small heat capacities. Stability is only limited by the Hamiltonian part of the dynamics, which suggests resorting to multiple timestep strategies where the stochastic part is integrated less frequently than the Hamiltonian one.

  14. Generalized Dynamic Factor Models for Mixed-Measurement Time Series.

    PubMed

    Cui, Kai; Dunson, David B

    2014-02-12

    In this article, we propose generalized Bayesian dynamic factor models for jointly modeling mixed-measurement time series. The framework allows mixed-scale measurements associated with each time series, with different measurements having different distributions in the exponential family conditionally on time-varying latent factor(s). Efficient Bayesian computational algorithms are developed for posterior inference on both the latent factors and model parameters, based on a Metropolis Hastings algorithm with adaptive proposals. The algorithm relies on a Greedy Density Kernel Approximation (GDKA) and parameter expansion with latent factor normalization. We tested the framework and algorithms in simulated studies and applied them to the analysis of intertwined credit and recovery risk for Moody's rated firms from 1982-2008, illustrating the importance of jointly modeling mixed-measurement time series. The article has supplemental materials available online.

  15. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-09-27

    Dinosaur tracker Ray Stanford describes the cretaceous-era nodosaur track he found on the Goddard Space Flight Center campus this year. The imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more about this discovery go to: 1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  16. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-09-27

    This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more go to: 1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  17. Estimating the granularity coefficient of a Potts-Markov random field within a Markov chain Monte Carlo algorithm.

    PubMed

    Pereyra, Marcelo; Dobigeon, Nicolas; Batatia, Hadj; Tourneret, Jean-Yves

    2013-06-01

    This paper addresses the problem of estimating the Potts parameter β jointly with the unknown parameters of a Bayesian model within a Markov chain Monte Carlo (MCMC) algorithm. Standard MCMC methods cannot be applied to this problem because performing inference on β requires computing the intractable normalizing constant of the Potts model. In the proposed MCMC method, the estimation of β is conducted using a likelihood-free Metropolis-Hastings algorithm. Experimental results obtained for synthetic data show that estimating β jointly with the other unknown parameters leads to estimation results that are as good as those obtained with the actual value of β. On the other hand, choosing an incorrect value of β can degrade estimation performance significantly. To illustrate the interest of this method, the proposed algorithm is successfully applied to real bidimensional SAR and tridimensional ultrasound images.

  18. Clinical utility of EEG in attention deficit hyperactivity disorder.

    PubMed

    Loo, Sandra K; Barkley, Russell A

    2005-01-01

    Electrophysiological measures were among the first to be used to study brain processes in children with attention deficit hyperactivity disorder (ADHD; Diagnostic and Statistical Manual of Mental Disorders [4th ed.], American Psychiatric Association, 1994) and have been used as such for over 30 years (see Hastings & Barkley, 1978, for an early review). More recently, electroencephalography (EEG) has been used both in research to describe and quantify the underlying neurophysiology of ADHD, but also clinically in the assessment, diagnosis, and treatment of ADHD. This review will first provide a brief overview of EEG and then present some of the research findings of EEG correlates in ADHD. Then, the utility of EEG in making an ADHD diagnosis and predicting stimulant response will be examined. Finally, and more controversially, we will review the results of the most recent studies on EEG biofeedback (neurofeedback) as a treatment for ADHD and the issues that remain to be addressed in the research examining the efficacy this therapeutic approach.

  19. Markov Chain Monte Carlo from Lagrangian Dynamics

    PubMed Central

    Lan, Shiwei; Stathopoulos, Vasileios; Shahbaba, Babak; Girolami, Mark

    2014-01-01

    Hamiltonian Monte Carlo (HMC) improves the computational e ciency of the Metropolis-Hastings algorithm by reducing its random walk behavior. Riemannian HMC (RHMC) further improves the performance of HMC by exploiting the geometric properties of the parameter space. However, the geometric integrator used for RHMC involves implicit equations that require fixed-point iterations. In some cases, the computational overhead for solving implicit equations undermines RHMC's benefits. In an attempt to circumvent this problem, we propose an explicit integrator that replaces the momentum variable in RHMC by velocity. We show that the resulting transformation is equivalent to transforming Riemannian Hamiltonian dynamics to Lagrangian dynamics. Experimental results suggests that our method improves RHMC's overall computational e ciency in the cases considered. All computer programs and data sets are available online (http://www.ics.uci.edu/~babaks/Site/Codes.html) in order to allow replication of the results reported in this paper. PMID:26240515

  20. In the ruins of Babel: pitfalls on the way toward a universal language for research ethics and benefit sharing.

    PubMed

    Solbakk, Jan Helge

    2011-07-01

    At the end of a paper on international research ethics published in the July-August 2010 issue of the Hastings Center Report, London and Zollman argue the need for grounding our duties in international medical and health-related research within a broader normative framework of social, distributive, and rectificatory justice. The same goes for Thomas Pogge, who, in a whole range of publications during the past years, has argued for a human-rights-based approach to international research. In a thought-provoking paper in the June 2010 issue of the American Journal of Bioethics, Angela J. Ballantyne argues that “the global bioethics priority” in medical and health-related research ethics today is how to do research fairly in an unjust world.

  1. Constraints on topological order in mott insulators.

    PubMed

    Zaletel, Michael P; Vishwanath, Ashvin

    2015-02-20

    We point out certain symmetry induced constraints on topological order in Mott insulators (quantum magnets with an odd number of spin 1/2 moments per unit cell). We show, for example, that the double-semion topological order is incompatible with time reversal and translation symmetry in Mott insulators. This sharpens the Hastings-Oshikawa-Lieb-Schultz-Mattis theorem for 2D quantum magnets, which guarantees that a fully symmetric gapped Mott insulator must be topologically ordered, but is silent about which topological order is permitted. Our result applies to the kagome lattice quantum antiferromagnet, where recent numerical calculations of the entanglement entropy indicate a ground state compatible with either toric code or double-semion topological order. Our result rules out the latter possibility.

  2. Functional MRI of the thoracic spinal cord during vibration sensation.

    PubMed

    Kornelsen, Jennifer; Smith, Stephen D; McIver, Theresa A; Sboto-Frankenstein, Uta; Latta, Peter; Tomanek, Boguslaw

    2013-04-01

    To demonstrate that it is possible to acquire accurate functional magnetic resonance images from thoracic spinal cord neurons. The lower thoracic spinal dermatomes (T7-T11) on the right side of the body were mechanically stimulated by vibration for 15 participants. Neuronal responses to vibration sensation were measured in the thoracic spinal cord using a HASTE sequence on a 3 Tesla MRI system. Signal increases were observed in the corresponding lower thoracic spinal cord segments ipsilateral to the side of stimulation in the dorsal aspect of the spinal cord. This is the first study to provide proof of principle that functional imaging of the entire thoracic spinal cord is possible, by detecting neuronal activity in the thoracic spinal cord during sensory stimulation using spinal fMRI. Copyright © 2012 Wiley Periodicals, Inc.

  3. [Mourning and depression, from the attachment theory perspective].

    PubMed

    Wolfberg, Elsa; Ekboir, Alberto; Faiman, Graciela; Finzi, Josefina; Freedman, Margarita; Heath, Adela; Martínez de Cipolatti, María C

    2011-01-01

    Since depression, according to OMS, is such a worldwide condition, it is necessary to be able to distinguish a normal mourning from a pathological mourning and a depression, so as to qualify patients and health professionals to be able to support a normal mourning without medicating it nor hurrying (hasting) it, as well as being able to treat a depression adequately when it appears as a complication. Attachment theory focuses on mourning after loss with notions such as 1- acceptance of search for the lost person as a normal fact; 2- that mourning in children may have non-pathological outcomes; 3- that a non-processed mourning may be transmitted in an intergenerational way, and 4- also defines which elements may determine a pathological mourning or a depression. A clinical case is presented with an analysis of these notions.

  4. A Bayesian Approach to Learning Scoring Systems.

    PubMed

    Ertekin, Şeyda; Rudin, Cynthia

    2015-12-01

    We present a Bayesian method for building scoring systems, which are linear models with coefficients that have very few significant digits. Usually the construction of scoring systems involve manual effort-humans invent the full scoring system without using data, or they choose how logistic regression coefficients should be scaled and rounded to produce a scoring system. These kinds of heuristics lead to suboptimal solutions. Our approach is different in that humans need only specify the prior over what the coefficients should look like, and the scoring system is learned from data. For this approach, we provide a Metropolis-Hastings sampler that tends to pull the coefficient values toward their "natural scale." Empirically, the proposed method achieves a high degree of interpretability of the models while maintaining competitive generalization performances.

  5. 31. WEST TO PARTS AND TOOLS LOCATED DIRECTLY OPPOSITE FROM ...

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

    31. WEST TO PARTS AND TOOLS LOCATED DIRECTLY OPPOSITE FROM THE BLACKSMITH SHOP AREA IN THE NORTHEAST QUADRANT OF THE FACTORY. ON THE FLOOR AT THE LEFT SIDE IS A MANUAL PIPE THREADER FOR LARGE-DIAMETER PIPE (AS DROP PIPE IN WELLS FOR WATER SYSTEMS). BENEATH THE BENCH ARE UNMACHINED NEW OLD STOCK MAIN CASTINGS FOR ELI WINDMILLS, TOGETHER WITH A USED MAIN SHAFT/WHEEL HUB/CRANK PLATE ASSEMBLY WITH 1920S-1930S OIL RESERVOIR FROM ELI WINDMILL. THE CIRCULAR CASTING WITH CRESCENT-SHAPED PATTERNS IS A PORTION OF THE CAM MECHANISM FROM A 'WESTERN GEARED GEARLESS' WINDMILL MADE BY THE WESTERN LAND ROLLER CO., HASTINGS, NEB. TO THE RIGHT ON THE BENCH IS A GEARED TIRE BENDER USED TO GIVE CURVATURE TO WHEEL RIMS OF ELI WINDMILLS. IN THE BACKGROUND ARE ... - Kregel Windmill Company Factory, 1416 Central Avenue, Nebraska City, Otoe County, NE

  6. Adaptive Metropolis Sampling with Product Distributions

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Lee, Chiu Fan

    2005-01-01

    The Metropolis-Hastings (MH) algorithm is a way to sample a provided target distribution pi(z). It works by repeatedly sampling a separate proposal distribution T(x,x') to generate a random walk {x(t)}. We consider a modification of the MH algorithm in which T is dynamically updated during the walk. The update at time t uses the {x(t' less than t)} to estimate the product distribution that has the least Kullback-Leibler distance to pi. That estimate is the information-theoretically optimal mean-field approximation to pi. We demonstrate through computer experiments that our algorithm produces samples that are superior to those of the conventional MH algorithm.

  7. Evaluation of Data Retention and Imprint Characteristics of FRAMs Under Environmental Stresses for NASA Applications

    NASA Technical Reports Server (NTRS)

    Sharma, Asbok K.; Teverovsky, Alexander; Dowdy, Terry W.; Hamilton, Brett

    2002-01-01

    A major reliability issue for all advanced nonvolatile memory (NVM) technology devices including FRAMs is the data retention characteristics over extended period of time, under environmental stresses and exposure to total ionizing dose (TID) radiation effects. For this testing, 256 Kb FRAMs in 28-pin plastic DIPS, rated for industrial grade temperature range of -40 C to +85 C, were procured. These are two-transistor, two-capacitor (2T-2C) design FRAMs. In addition to data retention characteristics, the parts were also evaluated for imprint failures, which are defined as the failure of cells to change from a "preferred" state, where it has been for a significant period of time to an opposite state (e.g., from 1 to 0, or 0 to 1). These 256 K FRAMs were subjected to scanning acoustic microscopy (C-SAM); 1,000 temperature cycles from -65 C to +150 C; high temperature aging at 150 C, 175 C, and 200 C for 1,000 hours; highly accelerated stress test (HAST) for 500 hours; 1,000 hours of operational life test at 125 C; and total ionizing dose radiation testing. As a preconditioning, 10 K read/write cycles were performed on all devices. Interim electrical measurements were performed throughout this characterization, including special imprint testing and final electrical testing. Some failures were observed during high temperature aging test at 200 C, during HAST testing, and during 1,000 hours of operational life at 125 C. The parts passed 10 Krad exposure, but began showing power supply current increases during the dose increment from 10 Krad to 30 Krad, and at 40 Krad severe data retention and parametric failures were observed. Failures from various environmental group testing are currently being analyzed.

  8. Evaluation of Data Retention and Imprint Characteristics of FRAMs Under Environmental Stresses for NASA Applications

    NASA Technical Reports Server (NTRS)

    Sharma, Ashok K.; Teverovsky, Alexander; Dowdy, Terry W.; Hamilton, Brett

    2000-01-01

    A major reliability issue for all advanced nonvolatile memory (NVM) technology devices including FRAMs (Ferroelectric random access memories) is the data retention characteristics over extended period of time, under environmental stresses and exposure to total ionizing dose (TID) radiation effects. For this testing, 256 Kb FRAMs in 28-pin plastic DIPS, rated for industrial grade temperature range of -40 C to +85 C, were procured. These are two-transistor, two-capacitor (2T-2C) design FRAMs. In addition to data retention characteristics, the parts were also evaluated for imprint failures, which are defined as the failure of cells to change from a "preferred" state, where it has been for a significant period of time to an opposite state (e.g., from 1 to 0, or 0 to 1). These 256 K FRAMs were subjected to scanning acoustic microscopy (C-SAM); 1,000 temperature cycles from -65 C to +150 C; high temperature aging at 150 C, 175 C, and 200 C for 1,000 hours; highly accelerated stress test (HAST) for 500 hours; 1,000 hours of operational life test at 125 C; and total ionizing dose radiation testing. As a preconditioning, 10 K read/write cycles were performed on all devices. Interim electrical measurements were performed throughout this characterization, including special imprint testing and final electrical testing. Some failures were observed during high temperature aging test at 200 C, during HAST testing, and during 1,000 hours of operational life at 125 C. The parts passed 10 Krad exposure, but began showing power supply current increases during the dose increment from 10 Krad to 30 Krad, and at 40 Krad severe data retention and parametric failures were observed. Failures from various environmental group testing are currently being analyzed.

  9. The Lake Charles CCS Project

    SciTech Connect

    Doug Cathro

    2010-06-30

    The Lake Charles CCS Project is a large-scale industrial carbon capture and sequestration (CCS) project which will demonstrate advanced technologies that capture and sequester carbon dioxide (CO{sub 2}) emissions from industrial sources into underground formations. Specifically the Lake Charles CCS Project will accelerate commercialization of large-scale CO{sub 2} storage from industrial sources by leveraging synergy between a proposed petroleum coke to chemicals plant (the LCC Gasification Project) and the largest integrated anthropogenic CO{sub 2} capture, transport, and monitored sequestration program in the U.S. Gulf Coast Region. The Lake Charles CCS Project will promote the expansion of EOR in Texas and Louisiana and supply greater energy security by expanding domestic energy supplies. The capture, compression, pipeline, injection, and monitoring infrastructure will continue to sequester CO{sub 2} for many years after the completion of the term of the DOE agreement. The objectives of this project are expected to be fulfilled by working through two distinct phases. The overall objective of Phase 1 was to develop a fully definitive project basis for a competitive Renewal Application process to proceed into Phase 2 - Design, Construction and Operations. Phase 1 includes the studies attached hereto that will establish: the engineering design basis for the capture, compression and transportation of CO{sub 2} from the LCC Gasification Project, and the criteria and specifications for a monitoring, verification and accounting (MVA) plan at the Hastings oil field in Texas. The overall objective of Phase 2, provided a successful competitive down-selection, is to execute design, construction and operations of three capital projects: (1) the CO{sub 2} capture and compression equipment, (2) a Connector Pipeline from the LLC Gasification Project to the Green Pipeline owned by Denbury and an affiliate of Denbury, and (3) a comprehensive MVA system at the Hastings oil field.

  10. TU-F-BRF-06: 3D Pancreas MRI Segmentation Using Dictionary Learning and Manifold Clustering

    SciTech Connect

    Gou, S; Rapacchi, S; Hu, P; Sheng, K

    2014-06-15

    Purpose: The recent advent of MRI guided radiotherapy machines has lent an exciting platform for soft tissue target localization during treatment. However, tools to efficiently utilize MRI images for such purpose have not been developed. Specifically, to efficiently quantify the organ motion, we develop an automated segmentation method using dictionary learning and manifold clustering (DLMC). Methods: Fast 3D HASTE and VIBE MR images of 2 healthy volunteers and 3 patients were acquired. A bounding box was defined to include pancreas and surrounding normal organs including the liver, duodenum and stomach. The first slice of the MRI was used for dictionary learning based on mean-shift clustering and K-SVD sparse representation. Subsequent images were iteratively reconstructed until the error is less than a preset threshold. The preliminarily segmentation was subject to the constraints of manifold clustering. The segmentation results were compared with the mean shift merging (MSM), level set (LS) and manual segmentation methods. Results: DLMC resulted in consistently higher accuracy and robustness than comparing methods. Using manual contours as the ground truth, the mean Dices indices for all subjects are 0.54, 0.56 and 0.67 for MSM, LS and DLMC, respectively based on the HASTE image. The mean Dices indices are 0.70, 0.77 and 0.79 for the three methods based on VIBE images. DLMC is clearly more robust on the patients with the diseased pancreas while LS and MSM tend to over-segment the pancreas. DLMC also achieved higher sensitivity (0.80) and specificity (0.99) combining both imaging techniques. LS achieved equivalent sensitivity on VIBE images but was more computationally inefficient. Conclusion: We showed that pancreas and surrounding normal organs can be reliably segmented based on fast MRI using DLMC. This method will facilitate both planning volume definition and imaging guidance during treatment.

  11. Pulse oximetry in the preflight evaluation of patients with chronic obstructive pulmonary disease.

    PubMed

    Akerø, Aina; Christensen, Carl C; Edvardsen, Anne; Ryg, Morten; Skjønsberg, Ole H

    2008-05-01

    In a British Thoracic Society (BTS) statement on preflight evaluation of patients with respiratory disease, sea level pulse oximetry (Spo2sl) is recommended as an initial assessment. The present study aimed to evaluate if the BTS algorithm can be used to identify chronic obstructive pulmonary disease (COPD) patients in need of supplemental oxygen during air travel, i.e. patients with an in-flight PaO2 < 6.6 kPa (50 mmHg). There were 100 COPD patients allocated to groups according to the BTS algorithm: Spo2sl > 95%, Spo2sl 92-95% without additional risk factors; Spo2sl 92-95% with additional risk factors; Spo2sl < 92%; and patients using domiciliary oxygen. Pulse oximetry, arterial blood gases, and an hypoxia-altitude simulation test (HAST) to simulate a cabin altitude of 2438 m (8000 ft), were performed. The percentage of patients in the various groups dropping below 6.6 kPa during HAST were: Spo2sl > 95%: 30%; Spo2sl 92-95% without additional risk factors: 67%; Spo2sl 92-95% with additional risk factors: 70%; Spo2sl < 92%: 83%; and patients using domiciliary oxygen: 81%. In patients dropping below P(a)o(2) 6.6 kPa, supplemental oxygen of median 1 L x min(-1) was needed to exceed this limit. If in-flight P(a)o(2) > or = 6.6 kPa is regarded as a strict requirement, the use of pulse oximetry as an initial assessment in the preflight evaluation of COPD patients, as suggested by the BTS, might not discriminate adequately between patients who fulfill the indications for supplemental oxygen during air travel, and patients who can travel without such treatment.

  12. Structural inversion of the Tamworth Belt: Insights into the development of orogenic curvature in the southern New England Orogen, Australia

    NASA Astrophysics Data System (ADS)

    Phillips, G.; Robinson, J.; Glen, R.; Roberts, J.

    2016-05-01

    The middle to late Permian Hunter Bowen Event is credited with the development of orogenic curvature in the southern New England Orogen, yet contention surrounds the structural dynamics responsible for the development of this curvature. Debate is largely centred on the roles of orogen parallel strike-slip and orogen normal extension and contraction to explain the development of curvature. To evaluate the dynamic history of the Hunter Bowen Event, we present new kinematic reconstructions of the Tamworth Belt. The Tamworth Belt formed as a Carboniferous forearc basin and was subsequently inverted during the Hunter Bowen Event. Kinematic reconstructions of the Tamworth Belt are based on new maps and cross-sections built from a synthesis of best-available mapping, chronostratigraphic data and new interpretations of depth-converted seismic data. The following conclusions are made from our study: (i) the Hunter Bowen Event was dominantly driven by margin normal contraction (east-west shortening; present-day coordinates), and; (ii) variations in structural style along the strike of the Tamworth Belt can be explained by orthogonal vs. oblique inversion, which reflects the angular relationship between the principal shortening vector and continental-arc margin. Given these conclusions, we suggest that curvature around the controversial Manning Bend was influenced by the presence of primary curvature in the continental margin, and that the Hastings Block was translated along a sinistral strike-slip fault system that formed along this oblique (with respect to the regional east-west extension and convergence direction) part of the margin. Given the available temporal data, the translation of the Hastings Block took place in the Early Permian (Asselian) and therefore preceded the Hunter Bowen Event. Accordingly, we suggest that the Hunter Bowen Event was dominantly associated with enhancing curvature that was either primary in origin, or associated with fault block translation

  13. Detection and molecular characterization of diarrhea causing viruses in single and mixed infections in children: a comparative study between Bangladesh and Turkey.

    PubMed

    Mitui, Marcelo Takahiro; Bozdayi, Gulendam; Ahmed, Selim; Matsumoto, Takashi; Nishizono, Akira; Ahmed, Kamruddin

    2014-07-01

    The incidence and mortality caused by diarrhea differ among countries. The prevalence of different enteric viruses, their molecular characteristics, and infections with multiple viruses might affect the disease incidence and mortality caused by diarrhea. The objective of this study was to determine the distribution and molecular characteristics of enteric viruses in children with diarrhea in Turkey and Bangladesh. A total of 288 stool samples that were negative for group A rotavirus were collected from children aged <5 years with acute diarrhea who presented to hospitals in Turkey and Bangladesh. The samples were screened for human bocavirus (HBoV), astrovirus (HAstV), norovirus (NoV), and adenovirus (AdV). Phylogenetic analyses of the targeted virus genes were performed. In Turkey, viruses were detected in 87/150 samples (58%), which included 69 (79.3%) with single viruses and 18 (20.7%) with multiple viruses. AdV was the most common virus, followed by HBoV. In Bangladesh, viruses were detected in 123/138 samples (89.1%), which included 29 (23.6%) with single viruses and 94 (76.4%) with multiple viruses. NoV GII was the most common, followed by AdV. The dominant genotypes among the virus species were HBoV 2A, HAstV 1, NoV GI type 1, and AdV 40. For NoV GII, the Hunter variant of genotype 4 in Turkey and genotype 17 in Bangladesh were the most common among the sequenced strains. It was concluded that the distribution of the viruses associated with diarrhea in Turkish and Bangladeshi children was different. Enteric viruses and mixed infections were more prevalent in Bangladesh than in Turkey. © 2013 Wiley Periodicals, Inc.

  14. Does telephone triage of emergency (999) calls using advanced medical priority dispatch (AMPDS) with Department of Health (DH) call prioritisation effectively identify patients with an acute coronary syndrome? An audit of 42 657 emergency calls to Hampshire Ambulance Service NHS Trust

    PubMed Central

    Deakin, C D; Sherwood, D M; Smith, A; Cassidy, M

    2006-01-01

    Introduction The National Service Framework for Coronary Heart Disease requires identification of patients with an acute coronary syndrome (ACS) to enable prompt identification of those who may subsequently require pre‐hospital thrombolysis. The Advanced Medical Priority Despatch System (AMPDS) with Department of Health (DH) call prioritisation is now the common triage tool for emergency (‘999') calls in the UK. We retrospectively examined patients with ACS to identify whether this triage tool had been able to allocate an appropriate emergency response. Methods All emergency calls to Hampshire Ambulance Service NHS Trust (HAST) from the Southampton area over an 8 month period (January to August 2004) were analysed. The classification allocated to the patient by AMPDS (version 10.4) was specifically identified. Data from the Myocardial Infarct National Audit Project) were obtained from the receiving hospital in Southampton to identify the actual number of patients with a true ACS. Results In total, 42 657 emergency calls were made to HAST from the Southampton area. Of these, 263 patients were subsequently diagnosed in hospital as having an ACS. Of these 263 patients, 76 presented without chest pain. Sensitivity of AMPDS for detecting ACS in this sample was 71.1% and specificity 92.5%. Positive predictive value was 5.6% (95% confidence interval 4.8 to 6.4%), and 12.5% (33/263) of patients with confirmed ACS were classified as non‐life threatening (category B) incidents. Conclusion Only one of approximately every 18 patients with chest pain has an ACS. AMPDS with DH call prioritisation is not a tool designed for clinical diagnosis, and its extension into this field does not enable accurate identification of patients with ACS. PMID:16498168

  15. Application of Magnetic Resonance Imaging to Measure Fasting and Postprandial Volumes in Humans

    PubMed Central

    Fidler, Jeff; Bharucha, Adil E.; Camilleri, Michael; Camp, Jon; Burton, Duane; Grimm, Roger; Riederer, Stephen J.; Robb, Richard A.; Zinsmeister, Alan R.

    2008-01-01

    Our aims were to measure the gastric volume response in excess of ingested meal volume (i.e., gastric accommodation), contribution of swallowed air to this excess, day-to-day variability of gastric volumes measured by MRI and their relationship to volumes measured by single-photon-emission computed tomography (SPECT). In 20 healthy volunteers, fasting and postprandial gastric volumes were measured after technetium99m-pertechnetate labeling of the gastric mucosa by SPECT and separately by MRI, using 3D gradient echo and 2D half-Fourier acquisition single-shot turbo spin echo (HASTE) sequences. Ten of these subjects had a second MRI exam to assess intra-individual variation. Thereafter, another 10 subjects had 2 MRI studies during which they ingested the nutrient in 30 or 150 mL aliquots. During MRI, the postprandial gastric volume change exceeded the ingested meal volume by 106 ± 12 mL (Mean ± SEM). The HASTE and gradient echo sequences distinguished air from fluid under fasting and postprandial conditions respectively. This postprandial excess mainly comprised air (61 ± 5 mL), which was not significantly different when ingested as 30 mL or 150 mL aliquots. Fasting and postprandial gastric volumes measured by MRI were generally reproducible within subjects. During SPECT, postprandial volumes increased by 158 ± 18 mL; gastric volumes measured by SPECT were higher than MRI. MRI measures gastric volumes with acceptable performance characteristics; the postprandial excess primarily consists of air, which is not affected by the mode of ingestion. Gastric volumes are technique specific and differ between MRI and SPECT. PMID:19019018

  16. MR Imaging of Pulmonary Nodules: Detection Rate and Accuracy of Size Estimation in Comparison to Computed Tomography

    PubMed Central

    Cieszanowski, Andrzej; Lisowska, Antonina; Dabrowska, Marta; Korczynski, Piotr; Zukowska, Malgorzata; Grudzinski, Ireneusz P.; Pacho, Ryszard; Rowinski, Olgierd; Krenke, Rafal

    2016-01-01

    Objective The aims of this study were to assess the sensitivity of various magnetic resonance imaging (MRI) sequences for the diagnosis of pulmonary nodules and to estimate the accuracy of MRI for the measurement of lesion size, as compared to computed tomography (CT). Methods Fifty patients with 113 pulmonary nodules diagnosed by CT underwent lung MRI and CT. MRI studies were performed on 1.5T scanner using the following sequences: T2-TSE, T2-SPIR, T2-STIR, T2-HASTE, T1-VIBE, and T1-out-of-phase. CT and MRI data were analyzed independently by two radiologists. Results The overall sensitivity of MRI for the detection of pulmonary nodules was 80.5% and according to nodule size: 57.1% for nodules ≤4mm, 75% for nodules >4-6mm, 87.5% for nodules >6-8mm and 100% for nodules >8mm. MRI sequences yielded following sensitivities: 69% (T1-VIBE), 54.9% (T2-SPIR), 48.7% (T2-TSE), 48.7% (T1-out-of-phase), 45.1% (T2-STIR), 25.7% (T2-HASTE), respectively. There was very strong agreement between the maximum diameter of pulmonary nodules measured by CT and MRI (mean difference -0.02 mm; 95% CI –1.6–1.57 mm; Bland-Altman analysis). Conclusions MRI yielded high sensitivity for the detection of pulmonary nodules and enabled accurate assessment of their diameter. Therefore it may be considered an alternative to CT for follow-up of some lung lesions. However, due to significant number of false positive diagnoses, it is not ready to replace CT as a tool for lung nodule detection. PMID:27258047

  17. Diversity in the Enteric Viruses Detected in Outbreaks of Gastroenteritis from Mumbai, Western India

    PubMed Central

    Chitambar, Shobha; Gopalkrishna, Varanasi; Chhabra, Preeti; Patil, Pooja; Verma, Harsha; Lahon, Anismrita; Arora, Ritu; Tatte, Vaishali; Ranshing, Sujata; Dhale, Ganesh; Kolhapure, Rajendra; Tikute, Sanjay; Kulkarni, Jagannath; Bhardwaj, Renu; Akarte, Sulbha; Pawar, Sashikant

    2012-01-01

    Faecal specimens collected from two outbreaks of acute gastroenteritis that occurred in southern Mumbai, India in March and October, 2006 were tested for seven different enteric viruses. Among the 218 specimens tested, 95 (43.6%) were positive, 73 (76.8%) for a single virus and 22 (23.2%) for multiple viruses. Single viral infections in both, March and October showed predominance of enterovirus (EV, 33.3% and 40%) and rotavirus A (RVA, 33.3% and 25%). The other viruses detected in these months were norovirus (NoV, 12.1% and 10%), rotavirus B (RVB, 12.1% and 10%), enteric adenovirus (AdV, 6.1% and 7.5%), Aichivirus (AiV, 3% and 7.5%) and human astrovirus (HAstV, 3% and 0%). Mixed viral infections were largely represented by two viruses (84.6% and 88.9%), a small proportion showed presence of three (7.7% and 11%) and four (7.7% and 0%) viruses in the two outbreaks. Genotyping of the viruses revealed predominance of RVA G2P[4], RVB G2 (Indian Bangladeshi lineage), NoV GII.4, AdV-40, HAstV-8 and AiV B types. VP1/2A junction region based genotyping showed presence of 11 different serotypes of EVs. Although no virus was detected in the tested water samples, examination of both water and sewage pipelines in gastroenteritis affected localities indicated leakages and possibility of contamination of drinking water with sewage water. Coexistence of multiple enteric viruses during the two outbreaks of gastroenteritis emphasizes the need to expand such investigations to other parts of India. PMID:22690171

  18. Building test data from real outbreaks for evaluating detection algorithms.

    PubMed

    Texier, Gaetan; Jackson, Michael L; Siwe, Leonel; Meynard, Jean-Baptiste; Deparis, Xavier; Chaudet, Herve

    2017-01-01

    Benchmarking surveillance systems requires realistic simulations of disease outbreaks. However, obtaining these data in sufficient quantity, with a realistic shape and covering a sufficient range of agents, size and duration, is known to be very difficult. The dataset of outbreak signals generated should reflect the likely distribution of authentic situations faced by the surveillance system, including very unlikely outbreak signals. We propose and evaluate a new approach based on the use of historical outbreak data to simulate tailored outbreak signals. The method relies on a homothetic transformation of the historical distribution followed by resampling processes (Binomial, Inverse Transform Sampling Method-ITSM, Metropolis-Hasting Random Walk, Metropolis-Hasting Independent, Gibbs Sampler, Hybrid Gibbs Sampler). We carried out an analysis to identify the most important input parameters for simulation quality and to evaluate performance for each of the resampling algorithms. Our analysis confirms the influence of the type of algorithm used and simulation parameters (i.e. days, number of cases, outbreak shape, overall scale factor) on the results. We show that, regardless of the outbreaks, algorithms and metrics chosen for the evaluation, simulation quality decreased with the increase in the number of days simulated and increased with the number of cases simulated. Simulating outbreaks with fewer cases than days of duration (i.e. overall scale factor less than 1) resulted in an important loss of information during the simulation. We found that Gibbs sampling with a shrinkage procedure provides a good balance between accuracy and data dependency. If dependency is of little importance, binomial and ITSM methods are accurate. Given the constraint of keeping the simulation within a range of plausible epidemiological curves faced by the surveillance system, our study confirms that our approach can be used to generate a large spectrum of outbreak signals.

  19. Building test data from real outbreaks for evaluating detection algorithms

    PubMed Central

    Texier, Gaetan; Jackson, Michael L.; Siwe, Leonel; Meynard, Jean-Baptiste; Deparis, Xavier; Chaudet, Herve

    2017-01-01

    Benchmarking surveillance systems requires realistic simulations of disease outbreaks. However, obtaining these data in sufficient quantity, with a realistic shape and covering a sufficient range of agents, size and duration, is known to be very difficult. The dataset of outbreak signals generated should reflect the likely distribution of authentic situations faced by the surveillance system, including very unlikely outbreak signals. We propose and evaluate a new approach based on the use of historical outbreak data to simulate tailored outbreak signals. The method relies on a homothetic transformation of the historical distribution followed by resampling processes (Binomial, Inverse Transform Sampling Method—ITSM, Metropolis-Hasting Random Walk, Metropolis-Hasting Independent, Gibbs Sampler, Hybrid Gibbs Sampler). We carried out an analysis to identify the most important input parameters for simulation quality and to evaluate performance for each of the resampling algorithms. Our analysis confirms the influence of the type of algorithm used and simulation parameters (i.e. days, number of cases, outbreak shape, overall scale factor) on the results. We show that, regardless of the outbreaks, algorithms and metrics chosen for the evaluation, simulation quality decreased with the increase in the number of days simulated and increased with the number of cases simulated. Simulating outbreaks with fewer cases than days of duration (i.e. overall scale factor less than 1) resulted in an important loss of information during the simulation. We found that Gibbs sampling with a shrinkage procedure provides a good balance between accuracy and data dependency. If dependency is of little importance, binomial and ITSM methods are accurate. Given the constraint of keeping the simulation within a range of plausible epidemiological curves faced by the surveillance system, our study confirms that our approach can be used to generate a large spectrum of outbreak signals. PMID

  20. Fetal Central Nervous System Anomalies Detected by Magnetic Resonance Imaging: A Two-Year Experience

    PubMed Central

    Sefidbakht, Sepideh; Dehghani, Sakineh; Safari, Maryam; Vafaei, Homeira; Kasraeian, Maryam

    2016-01-01

    Background Magnetic resonance imaging (MRI) is gradually becoming more common for thorough visualization of the fetus than ultrasound (US), especially for neurological anomalies, which are the most common indications for fetal MRI and are a matter of concern for both families and society. Objectives We investigated fetal MRIs carried out in our center for frequency of central nervous system anomalies. This is the first such report in southern Iran. Materials and Methods One hundred and seven (107) pregnant women with suspicious fetal anomalies in prenatal ultrasound entered a cross-sectional retrospective study from 2011 to 2013. A 1.5 T Siemens Avanto scanner was employed for sequences, including T2 HASTE and Trufisp images in axial, coronal, and sagittal planes to mother’s body, T2 HASTE and Trufisp relative to the specific fetal body part being evaluated, and T1 flash images in at least one plane based on clinical indication. We investigated any abnormality in the central nervous system and performed descriptive analysis to achieve index of frequency. Results Mean gestational age ± standard deviation (SD) for fetuses was 25.54 ± 5.22 weeks, and mean maternal age ± SD was 28.38 ± 5.80 years Eighty out of 107 (74.7%) patients who were referred with initial impression of borderline ventriculomegaly. A total of 18 out of 107 (16.82%) patients were found to have fetuses with CNS anomalies and the remainder were neurologically normal. Detected anomalies were as follow: 3 (16.6%) fetuses each had the Dandy-Walker variant and Arnold-Chiari II (with myelomeningocele). Complete agenesis of corpus callosum, partial agenesis of corpus callosum, and aqueductal stenosis were each seen in 2 (11.1%) fetuses. Arnold-Chiari II without myelomeningocele, anterior spina bifida associated with neurenteric cyst, arachnoid cyst, lissencephaly, and isolated enlarged cisterna magna each presented in one (5.5%) fetus. One fetus had concomitant schizencephaly and complete agenesis of

  1. Drowning of a barrier coastline under rapid rates of relative sea-level rise during the 8.2 ka cooling event: Cause or coincidence?

    NASA Astrophysics Data System (ADS)

    Mellett, C.; Hodgson, D. M.; Lang, A.; Mauz, B.; Plater, A. J.

    2012-12-01

    Examples where barrier landforms and deposits are preserved offshore of a highstand shoreline are rare on contemporary continental shelves, and in the rock record. Therefore, understanding of the conditions required for preservation and the sedimentary processes-response to such factors is limited and heavily dependent on simulation models. Here, an integrated dataset of multibeam bathymetry and 2D seismic reflection profiles has uncovered an exceptionally well preserved drowned barrier complex at Hastings Bank, on the English Channel continental shelf, offshore of southeast England. Mapping of nine seismic stratigraphic units calibrated with lithological information from multiple vibrocores has enabled the interpretation of fluvial, shoreface, barrier, washover fan, back-barrier and tidal environments of deposition. Stratigraphic architecture is used as the basis for landscape evolution reconstructions that reveal phases of barrier progradation, degradation and retreat. Optical Stimulated Luminescence (OSL) dating of shoreface and beach deposits revealed ages in the range of 8.4 ± 0.2 ka and 7.8 ± 0.2 ka. These ages indicate the barrier developed under rapid rates of early Holocene sea-level rise and more specifically, correlate to the time period surrounding the 8.2 ka cooling event and associated sea-level 'jump'. To preserve a barrier beach including the barrier foreshore under such rapid rates of relative sea-level rise, sediment supply would have to be sufficient to keep pace to prevent the shoreline responding through continuous reworking, i.e. rollover. Further, the rate of transgression is conditioned by inherited topography with higher rates of retreat, and hence greater potential for drowning, expected across the shallowly dipping substrate. Using Hastings Bank as an example, it has also been demonstrated that the morphodynamic state of the barrier complex in terms of its ability to respond dynamically to relative sea-level rise, conditions its

  2. Exotic ingredients in the mélange at Port Macquarie, southern New England Orogen, reveal a spicy history of crustal kneading along eastern Gondwana

    NASA Astrophysics Data System (ADS)

    Buckman, S.; Nutman, A.

    2013-12-01

    (sinistral) displacement of the Port Macquarie and Hastings Blocks and the dextral displacement of the Coffs Harbour Block associated with the Texas orocline, is apparent only, and due more in part to vertical displacements of an extensive, thin-skinned oceanic terranes that underlie the Tablelands Complex, rather than extensive lateral movements. Thus, there is no need to invoke large-scale ';oroclinal' folding or significant sinistral faulting to explain the repetition of Hastings and Port Macquarie blocks in the southern New England.

  3. Solution to the galactic foreground problem for LISA

    NASA Astrophysics Data System (ADS)

    Crowder, Jeff; Cornish, Neil J.

    2007-02-01

    Low frequency gravitational wave detectors, such as the Laser Interferometer Space Antenna (LISA), will have to contend with large foregrounds produced by millions of compact galactic binaries in our galaxy. While these galactic signals are interesting in their own right, the unresolved component can obscure other sources. The science yield for the LISA mission can be improved if the brighter and more isolated foreground sources can be identified and regressed from the data. Since the signals overlap with one another, we are faced with a “cocktail party” problem of picking out individual conversations in a crowded room. Here we present and implement an end-to-end solution to the galactic foreground problem that is able to resolve tens of thousands of sources from across the LISA band. Our algorithm employs a variant of the Markov chain Monte Carlo (MCMC) method, which we call the blocked annealed Metropolis-Hastings (BAM) algorithm. Following a description of the algorithm and its implementation, we give several examples ranging from searches for a single source to searches for hundreds of overlapping sources. Our examples include data sets from the first round of mock LISA data challenges.

  4. Antimalarial hybrid molecules: a close reality or a distant dream?

    PubMed

    Agarwal, Drishti; Gupta, Rinkoo D; Awasthi, Satish K

    2017-03-13

    Emergence of drug resistant Plasmodium falciparum strains has led to a situation of haste in the scientific and pharmaceutical communities. Hence, all their efforts are redirected towards finding alternate chemotherapeutic agents that are capable of combating multi-drug resistant parasite strains. In the above light, scientists have come up with the concept of hybridisation of two or more active pharmacophores into a single chemical entity, resulting in 'antimalarial hybrids.' The approach has been applied widely for lead generation against deadly diseases such as cancer and AIDS, with proven potential to be used as novel drugs, but is comparatively new in the sphere of antimalarial drug discovery. A sudden surge has been evidenced in the number of studies on design and synthesis of hybrids for treating malaria, and may be regarded as proof of their potential advantages over Artemisinin based Combination Therapy (ACT). However, it is evident from recent studies that most of the potential advantages of antimalarial hybrids, such as lower toxicity, better pharmacokinetics and easier formulation, have yet to be realised. A number of questions left unaddressed at present need to be answered before this approach can progress in to the late stages of clinical development and prove their worth in the clinic. To the best of our knowledge, this compilation is the first attempt to shed light over the shortcomings that are surfacing as more and more studies on molecular hybridization of the active pharmacophores of known antimalarials are being published.

  5. Charlie Gard and the Limits of Parental Authority.

    PubMed

    Caplan, Arthur; Folkers, Kelly McBride

    2017-09-01

    The parents of Charlie Gard, who was born August 4, 2016, with an exceedingly rare and incurable disease called mitochondrial DNA depletion syndrome, fought a prolonged and heated legal battle to allow him access to experimental treatment that they hoped would prolong his life and to prevent his doctors from withdrawing life-sustaining care. Charlie's clinicians at the Great Ormond Street Hospital in London believed that the brain damage Charlie had suffered as a result of frequent epileptic seizures, along with many other severe disabilities, would render any innovative therapy futile, and they disagreed with his parents' wishes to use an experimental therapy. They felt it in Charlie's best interest that he be allowed to die. A battle ensued among Charlie's parents, his doctors, and a guardian who had been appointed to represent him that drew the attention of politicians and prominent persons from all over the world. The case was much in the news over the past year, but it has also been frequently misunderstood. © 2017 The Hastings Center.

  6. Measurement Scale of the SOLIS Vector Spectromagnetograph

    NASA Technical Reports Server (NTRS)

    Jones, Harrison P.; Harvey, John W.; Henney, Carl J.; Keller, Christoph U.; Malanushenko, Olena M.

    2004-01-01

    Longitudinal magnetograms obtained with thc SOLIS Vector Spectromagnetograph (VSM) during a cross-calibration period are compared with similar data from the NASA/NSO Spectromagnetograph (SPM) at the NSO/Kitt Peak Vacuum Telescope as well as with SOHO/MDI and GONG magnetogram. The VSM began observation at the University of Arizona agricultural test site and collaborative observations were obtained with both the VSM and SPM from 2003 Aug 05 through 2003 Sep 21 where the SPM was officially retired. The VSM replaces the SPM and continues the 3O-year NSO/Kitt Peak synoptic magnetogram record. Magnetograms are compared by equating histograms and, for selected examples, by pixel-by-pixel comparison of co-registered images. The VSM was not corrected for polarization crosstalk and was operated without hast guiding. Solar activity was at best moderate during this period. Over the range of observed fields, the VSM magnetograms show greatly improved sensitivity but are otherwise virtually identical with "raw" SPM magnetogram. GONG magnetograms are also closely comparable with the SPM while MDI flux values tend to be stronger by a factor of 1.2 - 1.4. Dependence of the results on seeing will be discussed. Partial funding for this work was provided through Solar and Heliospheric Research Supporting Research and Technology grants from NASA's Office of Space Sciences.

  7. Dynamic semiparametric Bayesian models for genetic mapping of complex trait with irregular longitudinal data.

    PubMed

    Das, Kiranmoy; Li, Jiahan; Fu, Guifang; Wang, Zhong; Li, Runze; Wu, Rongling

    2013-02-10

    Many phenomena of fundamental importance to biology and biomedicine arise as a dynamic curve, such as organ growth and HIV dynamics. The genetic mapping of these traits is challenged by longitudinal variables measured at irregular and possibly subject-specific time points, in which case nonnegative definiteness of the estimated covariance matrix needs to be guaranteed. We present a semiparametric approach for genetic mapping within the mixture-model setting by jointly modeling mean and covariance structures for irregular longitudinal data. Penalized spline is used to model the mean functions of individual quantitative trait locus (QTL) genotypes as latent variables, whereas an extended generalized linear model is used to approximate the covariance matrix. The parameters for modeling the mean-covariances are estimated by MCMC, using the Gibbs sampler and the Metropolis-Hastings algorithm. We derive the full conditional distributions for the mean and covariance parameters and compute Bayes factors to test the hypothesis about the existence of significant QTLs. We used the model to screen the existence of specific QTLs for age-specific change of body mass index with a sparse longitudinal data set. The new model provides powerful means for broadening the application of genetic mapping to reveal the genetic control of dynamic traits.

  8. GRID-BASED EXPLORATION OF COSMOLOGICAL PARAMETER SPACE WITH SNAKE

    SciTech Connect

    Mikkelsen, K.; Næss, S. K.; Eriksen, H. K.

    2013-11-10

    We present a fully parallelized grid-based parameter estimation algorithm for investigating multidimensional likelihoods called Snake, and apply it to cosmological parameter estimation. The basic idea is to map out the likelihood grid-cell by grid-cell according to decreasing likelihood, and stop when a certain threshold has been reached. This approach improves vastly on the 'curse of dimensionality' problem plaguing standard grid-based parameter estimation simply by disregarding grid cells with negligible likelihood. The main advantages of this method compared to standard Metropolis-Hastings Markov Chain Monte Carlo methods include (1) trivial extraction of arbitrary conditional distributions; (2) direct access to Bayesian evidences; (3) better sampling of the tails of the distribution; and (4) nearly perfect parallelization scaling. The main disadvantage is, as in the case of brute-force grid-based evaluation, a dependency on the number of parameters, N{sub par}. One of the main goals of the present paper is to determine how large N{sub par} can be, while still maintaining reasonable computational efficiency; we find that N{sub par} = 12 is well within the capabilities of the method. The performance of the code is tested by comparing cosmological parameters estimated using Snake and the WMAP-7 data with those obtained using CosmoMC, the current standard code in the field. We find fully consistent results, with similar computational expenses, but shorter wall time due to the perfect parallelization scheme.

  9. Surveillance of patients affected by Peutz-Jeghers syndrome: diagnostic value of MR enterography in prone and supine position.

    PubMed

    Maccioni, F; Al Ansari, N; Mazzamurro, F; Barchetti, F; Marini, M

    2012-04-01

    Peutz-Jeghers syndrome (PJS) is a familial polyposis syndrome characterized by multiple hamartomatous polyps throughout the gastrointestinal tract. The aim of our study was to retrospectively determine the diagnostic value of MR enterography (MRE), performed in supine and prone position, in the detection of small bowel polyps in PJ patients. We retrospectively reviewed MRE examinations of 8 PJS patients who underwent MRE, pushed-double-ballon enteroscopy, laparoscopic endoscopy or surgery, within 3 months. Polietilenglicole was orally administered before the examination. True FISP and HASTE sequences were acquired in supine and prone position; 3D VIBE Gd-enhanced sequences in prone position only. Concordance between MRE and endoscopy was 72.6% for polyps <15 mm, 93% for polyps >15 mm. In supine and prone position concordance with endoscopy for polyps <15 mm was 63% and 66.8%, respectively. In the detection of smaller polyps the difference between supine position only and supine plus prone position was statistically significant (P < 0.027). MRE performed by combining prone and supine position was accurate in the detection of PJS polyps, with 93% concordance with enteroscopy for larger and more risky polyps. MRE offers a promising and non invasive alternative to capsule endoscopy, suggesting the possibility of an effective yearly surveillance in PJ patients.

  10. Saline as the Sole Contrast Agent for Successful MRI-guided Epidural Injections

    SciTech Connect

    Deli, Martin; Mateiescu, Serban Busch, Martin; Becker, Jan Garmer, Marietta Groenemeyer, Dietrich

    2013-06-15

    Purpose. To assess the performance of sterile saline solution as the sole contrast agent for percutaneous magnetic resonance imaging (MRI)-guided epidural injections at 1.5 T. Methods. A retrospective analysis of two different techniques of MRI-guided epidural injections was performed with either gadolinium-enhanced saline solution or sterile saline solution for documentation of the epidural location of the needle tip. T1-weighted spoiled gradient echo (FLASH) images or T2-weighted single-shot turbo spin echo (HASTE) images visualized the test injectants. Methods were compared by technical success rate, image quality, table time, and rate of complications. Results. 105 MRI-guided epidural injections (12 of 105 with gadolinium-enhanced saline solution and 93 of 105 with sterile saline solution) were performed successfully and without complications. Visualization of sterile saline solution and gadolinium-enhanced saline solution was sufficient, good, or excellent in all 105 interventions. For either test injectant, quantitative image analysis demonstrated comparable high contrast-to-noise ratios of test injectants to adjacent body substances with reliable statistical significance levels (p < 0.001). The mean table time was 22 {+-} 9 min in the gadolinium-enhanced saline solution group and 22 {+-} 8 min in the saline solution group (p = 0.75). Conclusion. Sterile saline is suitable as the sole contrast agent for successful and safe percutaneous MRI-guided epidural drug delivery at 1.5 T.

  11. [Hydro-MRT with fast sequences in Crohn's disease: a comparison with fractionated gastrointestinal passage].

    PubMed

    Schunk, K; Kern, A; Heussel, C P; Kalden, P; Orth, T; Wanitschke, R; Thelen, M

    1999-04-01

    To compare the value of hydro-MRI with that of barium studies in patients with Crohn's disease. After an oral bowel opacification using 1000 ml of a 2.5% mannitol solution, axial and coronal breath-hold sequences (T2W HASTE +/- FS, contrast-enhanced T1W FLASH FS) were acquired in 46 patients with Crohn's disease at 1.0 T. The findings of hydro-MRI were compared with those of barium studies. In the stomach and the small bowel, hydro-MRI and barium studies demonstrated similar numbers of Crohn's involvements (39 vs. 36); in the colon, hydro-MRI showed clearly more affections (23 vs. 10). Hydro-MRI showed 12.7 cm of inflamed bowel per patient, on average (barium studies: 10.4 cm; p = 0.004). There was a good agreement between the two methods regarding the assessment of the extent of Crohn's disease and the severity of bowel stenoses (r = 0.89 and 0.88, respectively). For the assessment of Crohn's disease, hydro-MRI is preferable to the barium study because of the superior imaging quality and the lack of radiation exposure.

  12. Shared uncertainty in measurement error problems, with application to Nevada Test Site fallout data.

    PubMed

    Li, Yehua; Guolo, Annamaria; Hoffman, F Owen; Carroll, Raymond J

    2007-12-01

    In radiation epidemiology, it is often necessary to use mathematical models in the absence of direct measurements of individual doses. When complex models are used as surrogates for direct measurements to estimate individual doses that occurred almost 50 years ago, dose estimates will be associated with considerable error, this error being a mixture of (a) classical measurement error due to individual data such as diet histories and (b) Berkson measurement error associated with various aspects of the dosimetry system. In the Nevada Test Site(NTS) Thyroid Disease Study, the Berkson measurement errors are correlated within strata. This article concerns the development of statistical methods for inference about risk of radiation dose on thyroid disease, methods that account for the complex error structure inherence in the problem. Bayesian methods using Markov chain Monte Carlo and Monte-Carlo expectation-maximization methods are described, with both sharing a key Metropolis-Hastings step. Regression calibration is also considered, but we show that regression calibration does not use the correlation structure of the Berkson errors. Our methods are applied to the NTS Study, where we find a strong dose-response relationship between dose and thyroiditis. We conclude that full consideration of mixtures of Berkson and classical uncertainties in reconstructed individual doses are important for quantifying the dose response and its credibility/confidence interval. Using regression calibration and expectation values for individual doses can lead to a substantial underestimation of the excess relative risk per gray and its 95% confidence intervals.

  13. NFL Physicians: Committed to Excellence in Patient-Player Care.

    PubMed

    2016-11-01

    The National Football League Physicians Society read with disappointment the article "A Proposal to Address NFL Club Doctors' Conflicts of Interest and to Promote Player Trust." In spite of the authors' suggestions, NFL physicians are accomplished medical professionals who abide by the highest ethical standards in providing treatment to all of their patients, including those who play in the NFL. It defies logic for the authors not to have engaged experienced and active NFL physicians from the very start of their effort to explore, challenge, and recommend significant alterations to the delivery of health care to NFL players. As troubling as this article is from so many perspectives, it does represent an opportunity for the NFLPS to set the record straight and call attention to the excellent quality of care NFL players receive. In addition, it represents an opportunity to expose the extraordinarily weak evidence presented in the article and to refute the baseless allegations that challenge the high ethical standards of NFL physicians. Contrary to solid scientific research that starts with a hypothesis based on theory, in this case, it seems quite apparent that the authors started with a predetermined conclusion and set out to justify it. Their premise was flawed, and they failed in their execution. © 2016 The Hastings Center.

  14. Preventing Conflicts of Interest of NFL Team Physicians.

    PubMed

    Rothstein, Mark A

    2016-11-01

    At least since the time of Hippocrates, the physician-patient relationship has been the paradigmatic ethical arrangement for the provision of medical care. Yet, a physician-patient relationship does not exist in every professional interaction involving physicians and individuals they examine or treat. There are several "third-party" relationships, mostly arising where the individual is not a patient and is merely being examined rather than treated, the individual does not select or pay the physician, and the physician's services are provided for the benefit of another party. Physicians who treat NFL players have a physician-patient relationship, but physicians who merely examine players to determine their health status have a third-party relationship. As described by Glenn Cohen et al., the problem is that typical NFL team doctors perform both functions, which leads to entrenched conflicts of interest. Although there are often disputes about treatment, the main point of contention between players and team physicians is the evaluation of injuries and the reporting of players' health status to coaches and other team personnel. Cohen et al. present several thoughtful recommendations that deserve serious consideration. Rather than focusing on their specific recommendations, however, I would like to explain the rationale for two essential reform principles: the need to sever the responsibilities of treatment and evaluation by team physicians and the need to limit the amount of player medical information disclosed to teams. © 2016 The Hastings Center.

  15. Health Care for NFL Players: Upholding Physician Standards and Enhancing the Doctor-Patient Relationship.

    PubMed

    Duvernay-Tardif, Laurent

    2016-11-01

    Beginning my third year with the Kansas City Chiefs and being also a medical student at McGill University, I was at first a little reluctant to comment on Glenn Cohen et al.'s critique of the National Football League's structure involving player health and team doctors, but the opportunity to provide a perspective as both a football player and a medical student was too much to forgo. Because of my athletic and academic background, I am often asked what I think about injuries in professional sports and about the role of sports medicine physicians, and Cohen et al.'s article demands a thoughtful reaction. I want to suggest that the fundamental principles concerning the medical profession and the doctor-patient relationship provide additional arguments for some of the solutions that Cohen et al. discuss. The professional self-regulation that the proposed medical committee could provide and the reliance on a doctor who was not hired by the player's employer-the club-for a second opinion are both good ways to minimize conflicts of interest. © 2016 The Hastings Center.

  16. Lessons for the NFL from Workers' Compensation.

    PubMed

    Diana, Richard

    2016-11-01

    In the article "A Proposal to Address NFL Club Doctors' Conflicts of Interest and to Promote Player Trust," Glenn Cohen et al. write, "The [NFL's] current structure forces club doctors to have obligations to two parties-the club and the player-and to make difficult judgments about when one party's interests must yield to another's." I can understand why some might be suspicious about bias in the current NFL medical system, in which the club doctors have a professional duty to put their player-patients' best interests first yet are employed by clubs, which have a primary goal of winning football games. It is my opinion, however, that neither the club nor the player needs to be sacrificed. I base this opinion partly on my experience as an NFL player in the early 1980s, partly on several years as team physician for the Boston Red Sox, and partly on my twenty-three-years of experience as a physician with the Connecticut Workers' Compensation medical system, which supposes that physicians can be fair to both workers and employers. © 2016 The Hastings Center.

  17. The Dual Role of NFL Team Doctors.

    PubMed

    Washington, Marvin

    2016-11-01

    Glenn Cohen, Holly Fernandez Lynch, and Christopher Deubert are right in their article "A Proposal to Address NFL Club Doctors' Conflicts of Interest and to Promote Player Trust" that the problem with the medical care rendered to National Football League players is not that the doctors are bad, but that the system in which they provide care is structured badly. We saw some of the problems this system causes last season in what happened to Case Kenum, a quarterback for the Los Angeles Rams who, despite having a possible concussion from a game injury, was allowed to continue to play, with a concussion spotter in the booth and coaches, teammates, seven game officials, and two full training staffs present. From my experience playing in the league from 1989 to 1999, I do not believe that you can eliminate the conflict of interest completely, but I think it can be limited to the point that it does not harm the player. As the structure is now, with the team paying the club doctor, it is impossible to put the players' health and well-being before the team's on-field priorities. © 2016 The Hastings Center.

  18. A Gibbs Sampler for Learning DAGs

    PubMed Central

    Goudie, Robert J. B.; Mukherjee, Sach

    2017-01-01

    We propose a Gibbs sampler for structure learning in directed acyclic graph (DAG) models. The standard Markov chain Monte Carlo algorithms used for learning DAGs are random-walk Metropolis-Hastings samplers. These samplers are guaranteed to converge asymptotically but often mix slowly when exploring the large graph spaces that arise in structure learning. In each step, the sampler we propose draws entire sets of parents for multiple nodes from the appropriate conditional distribution. This provides an efficient way to make large moves in graph space, permitting faster mixing whilst retaining asymptotic guarantees of convergence. The conditional distribution is related to variable selection with candidate parents playing the role of covariates or inputs. We empirically examine the performance of the sampler using several simulated and real data examples. The proposed method gives robust results in diverse settings, outperforming several existing Bayesian and frequentist methods. In addition, our empirical results shed some light on the relative merits of Bayesian and constraint-based methods for structure learning.

  19. Developing a cosmic ray muon sampling capability for muon tomography and monitoring applications

    NASA Astrophysics Data System (ADS)

    Chatzidakis, S.; Chrysikopoulou, S.; Tsoukalas, L. H.

    2015-12-01

    In this study, a cosmic ray muon sampling capability using a phenomenological model that captures the main characteristics of the experimentally measured spectrum coupled with a set of statistical algorithms is developed. The "muon generator" produces muons with zenith angles in the range 0-90° and energies in the range 1-100 GeV and is suitable for Monte Carlo simulations with emphasis on muon tomographic and monitoring applications. The muon energy distribution is described by the Smith and Duller (1959) [35] phenomenological model. Statistical algorithms are then employed for generating random samples. The inverse transform provides a means to generate samples from the muon angular distribution, whereas the Acceptance-Rejection and Metropolis-Hastings algorithms are employed to provide the energy component. The predictions for muon energies 1-60 GeV and zenith angles 0-90° are validated with a series of actual spectrum measurements and with estimates from the software library CRY. The results confirm the validity of the phenomenological model and the applicability of the statistical algorithms to generate polyenergetic-polydirectional muons. The response of the algorithms and the impact of critical parameters on computation time and computed results were investigated. Final output from the proposed "muon generator" is a look-up table that contains the sampled muon angles and energies and can be easily integrated into Monte Carlo particle simulation codes such as Geant4 and MCNP.

  20. Saving Science by Doing Less of It?

    PubMed

    Kaebnick, Gregory E

    2016-11-01

    In the current issue of The New Atlantis, Daniel Sarewitz, professor of science and society at Arizona State University, argues that science is broken because it is managed and judged by scientists themselves, operating under Vannevar Bush's famous 1945 declaration that scientific progress depends on the "free play of free intellects … dictated by their curiosity." With that scientific agenda, society ends up with a lot of unnecessary, uncoordinated, and unproductive research. To save science, holds Sarewitz, we need to put it in the hands of people who are looking for practical solutions to specific problems. In one article in this issue of the Hastings Center Report (November-December 2016), Kirstin Borgerson poses a question in this same conceptual space: are there too many clinical trials? Other pieces in the issue cover a mix of topics: the lead article addresses some of the challenges that will have to be faced as "artificial organs" become available, a third article looks at how crowdfunding sites like GoFundMe can be used to make public appeals for medical funding, and a special report found in a supplement to the issue offers a round of analysis and recommendations about the provision of medical care to professional football players.

  1. MCMC with strings and branes: The suburban algorithm (Extended Version)

    NASA Astrophysics Data System (ADS)

    Heckman, Jonathan J.; Bernstein, Jeffrey G.; Vigoda, Ben

    2017-08-01

    Motivated by the physics of strings and branes, we develop a class of Markov chain Monte Carlo (MCMC) algorithms involving extended objects. Starting from a collection of parallel Metropolis-Hastings (MH) samplers, we place them on an auxiliary grid, and couple them together via nearest neighbor interactions. This leads to a class of “suburban samplers” (i.e. spread out Metropolis). Coupling the samplers in this way modifies the mixing rate and speed of convergence for the Markov chain, and can in many cases allow a sampler to more easily overcome free energy barriers in a target distribution. We test these general theoretical considerations by performing several numerical experiments. For suburban samplers with a fluctuating grid topology, performance is strongly correlated with the average number of neighbors. Increasing the average number of neighbors above zero initially leads to an increase in performance, though there is a critical connectivity with effective dimension deff ˜ 1, above which “groupthink” takes over, and the performance of the sampler declines.

  2. Presence of viral proteins in drinkable water--sufficient condition to consider water a vector of viral transmission?

    PubMed

    Gutiérrez, M F; Alvarado, M V; Martínez, E; Ajami, N J

    2007-01-01

    In order to determine the role of water as a possible vector for transmission of the most prevalent enteric viruses affecting infantile populations, 226 water samples were collected from Facatativa's (Colombian municipality located 30km away from Bogotá) water works in the years 2000, 2002, and 2005. The samples were clarified and virus was concentrated by filtering and ultrafiltering techniques. The presence of viral protein (VP) was assessed by enzyme immunoassay method (EIA) and viral RNA presence was detected by reverse trascriptase and polymerase chain reaction (RT-PCR). Using these techniques, one sample positive for Astrovirus (HAstV) was found in a sample collected from the river that supplies the aqueduct, two samples positive for Norovirus (NV) from fresh treated potable water and 13 samples positive for Rotavirus (RV), some in water from the plant during treatment and others from treated fresh water. RT-PCR inhibitors were also found in water samples obtained from the plant and in the fresh treated water. No inhibitors were found in the river water. VP, but no nucleic acid, was detected in the water samples at different stages of treatment, thus suggesting that the virus might have been complete and infectious at some stage prior to water purification.

  3. Crowdfunding FOR MEDICAL CARE: Ethical Issues in an Emerging Health Care Funding Practice.

    PubMed

    Snyder, Jeremy

    2016-11-01

    Crowdfunding websites allow users to post a public appeal for funding for a range of activities, including adoption, travel, research, participation in sports, and many others. One common form of crowdfunding is for expenses related to medical care. Medical crowdfunding appeals serve as a means of addressing gaps in medical and employment insurance, both in countries without universal health insurance, like the United States, and countries with universal coverage limited to essential medical needs, like Canada. For example, as of 2012, the website Gofundme had been used to raise a total of 8.8 million dollars (U.S.) for seventy-six hundred campaigns, the majority of which were health related. This money can make an important difference in the lives of crowdfunding users, as the costs of unexpected or uninsured medical needs can be staggering. In this article, I offer an overview of the benefits of medical crowdfunding websites and the ethical concerns they raise. I argue that medical crowdfunding is a symptom and cause of, rather than a solution to, health system injustices and that policy-makers should work to address the injustices motivating the use of crowdfunding sites for essential medical services. Despite the sites' ethical problems, individual users and donors need not refrain from using them, but they bear a political responsibility to address the inequities encouraged by these sites. I conclude by suggesting some responses to these concerns and future directions for research. © 2016 The Hastings Center.

  4. The Virtues of National Ethics Committees.

    PubMed

    Montgomery, Jonathan

    2017-05-01

    The United Kingdom has many bodies that play their part in carrying out the work of national ethics committees, but its nearest equivalent of a U.S. presidential bioethics commission is the Nuffield Council on Bioethics, established in 1991. The Council is charged with examining ethical questions raised by developments in biological and medical research, publishing reports, and making representations to appropriate bodies in order to respond to or anticipate public concern. It is a nongovernment organization with no defined or guaranteed channels of influence. It has no authority merely by virtue of the position it holds. Rather, it has established relational authority based on its reputation. Unlike the U.S. bioethics commission, it is not part of executive government, nor is it constituted to contribute to the legislative branch, as does the French Comité Consultatif National d'Ethique. Its nongovernmental status notwithstanding, the Nuffield Council's work affects the U.K. government and the British public, and the Council has achieved international recognition for its reports. I was the chairperson from 2012 to 2017 and draw on my experience in this piece to consider three key audiences: governments, publics, and the international community. © 2017 The Hastings Center.

  5. Nodal predictive error model and Bayesian approach for thermal diffusivity and heat source mapping

    NASA Astrophysics Data System (ADS)

    Massard, H.; Fudym, Olivier; Orlande, H. R. B.; Batsale, J. C.

    2010-07-01

    This article aims at solving a two-dimensional inverse heat conduction problem in order to retrieve both the thermal diffusivity and heat source field in a thin plate. A spatial random heat pulse is applied to the plate and the thermal response is analysed. The inverse approach is based on the minimisation of a nodal predictive error model, which yields a linear estimation problem. As a result of this approach, the sensitivity matrix is directly filled with experimental data, and thus is partially noisy. Bayesian estimators, such as the Maximum A Posteriori and a Markov Chain Monte Carlo approach (Metropolis-Hastings), are implemented and compared with the Ordinary Least Squares solution. Simulated temperature measurements are used in the inverse analysis. The nodal strategy relies on the availability of temperature measurements with fine spatial resolution and high frequency, typical of nowadays infrared cameras. The effects of both the measurement errors and of the model errors on the inverse problem solution are also analysed.

  6. Staphylococcus aureus Develops an Alternative, ica-Independent Biofilm in the Absence of the arlRS Two-Component System†

    PubMed Central

    Toledo-Arana, Alejandro; Merino, Nekane; Vergara-Irigaray, Marta; Débarbouillé, Michel; Penadés, José R.; Lasa, Iñigo

    2005-01-01

    The biofilm formation capacity of Staphylococcus aureus clinical isolates is considered an important virulence factor for the establishment of chronic infections. Environmental conditions affect the biofilm formation capacity of S. aureus, indicating the existence of positive and negative regulators of the process. The majority of the screening procedures for identifying genes involved in biofilm development have been focused on genes whose presence is essential for the process. In this report, we have used random transposon mutagenesis and systematic disruption of all S. aureus two-component systems to identify negative regulators of S. aureus biofilm development in a chemically defined medium (Hussain-Hastings-White modified medium [HHWm]). The results of both approaches coincided in that they identified arlRS as a repressor of biofilm development under both steady-state and flow conditions. The arlRS mutant exhibited an increased initial attachment as well as increased accumulation of poly-N-acetylglucosamine (PNAG). However, the biofilm formation of the arlRS mutant was not affected when the icaADBC operon was deleted, indicating that PNAG is not an essential compound of the biofilm matrix produced in HHWm. Disruption of the major autolysin gene, atl, did not produce any effect on the biofilm phenotype of an arlRS mutant. Epistatic experiments with global regulators involved in staphylococcal-biofilm formation indicated that sarA deletion abolished, whereas agr deletion reinforced, the biofilm development promoted by the arlRS mutation. PMID:16030226

  7. Bayesian analysis of the flutter margin method in aeroelasticity

    NASA Astrophysics Data System (ADS)

    Khalil, Mohammad; Poirel, Dominique; Sarkar, Abhijit

    2016-12-01

    A Bayesian statistical framework is presented for Zimmerman and Weissenburger flutter margin method which considers the uncertainties in aeroelastic modal parameters. The proposed methodology overcomes the limitations of the previously developed least-square based estimation technique which relies on the Gaussian approximation of the flutter margin probability density function (pdf). Using the measured free-decay responses at subcritical (preflutter) airspeeds, the joint non-Gaussain posterior pdf of the modal parameters is sampled using the Metropolis-Hastings (MH) Markov chain Monte Carlo (MCMC) algorithm. The posterior MCMC samples of the modal parameters are then used to obtain the flutter margin pdfs and finally the flutter speed pdf. The usefulness of the Bayesian flutter margin method is demonstrated using synthetic data generated from a two-degree-of-freedom pitch-plunge aeroelastic model. The robustness of the statistical framework is demonstrated using different sets of measurement data. It will be shown that the probabilistic (Bayesian) approach reduces the number of test points required in providing a flutter speed estimate for a given accuracy and precision.

  8. Conflating Capacity & Authority: Why We're Asking the Wrong Question in the Adolescent Decision-Making Debate.

    PubMed

    Salter, Erica K

    2017-01-01

    Whether adolescents should be allowed to make their own medical decisions has been a topic of discussion in bioethics for at least two decades now. Are adolescents sufficiently capacitated to make their own medical decisions? Is the mature-minor doctrine, an uncommon legal exception to the rule of parental decision-making authority, something we should expand or eliminate? Bioethicists have dealt with the curious liminality of adolescents-their being neither children nor adults-in a variety of ways. However, recently there has been a trend to rely heavily, and often exclusively, on emerging neuroscientific and psychological data to answer these questions. Using data from magnetic resonance imaging and functional MRI studies on the adolescent brain, authors have argued both that the adolescent brain isn't sufficiently mature to broadly confer capacity on this population and that the adolescent brain is sufficiently mature to assume adolescent capacity. Scholars then accept these data as sufficient for concluding that adolescents should or should not have decision-making authority. Two critical mistakes are being made here. The first is the expectation that neuroscience or psychology is or will be able to answer all our questions about capacity. The second, and more concerning, mistake is the conflation of decision-making capacity with decision-making authority. © 2017 The Hastings Center.

  9. Bayesian model comparison of nonlinear structural equation models with missing continuous and ordinal categorical data.

    PubMed

    Lee, Sik-Yum; Song, Xin-Yuan

    2004-05-01

    Missing data are very common in behavioural and psychological research. In this paper, we develop a Bayesian approach in the context of a general nonlinear structural equation model with missing continuous and ordinal categorical data. In the development, the missing data are treated as latent quantities, and provision for the incompleteness of the data is made by a hybrid algorithm that combines the Gibbs sampler and the Metropolis-Hastings algorithm. We show by means of a simulation study that the Bayesian estimates are accurate. A Bayesian model comparison procedure based on the Bayes factor and path sampling is proposed. The required observations from the posterior distribution for computing the Bayes factor are simulated by the hybrid algorithm in Bayesian estimation. Our simulation results indicate that the correct model is selected more frequently when the incomplete records are used in the analysis than when they are ignored. The methodology is further illustrated with a real data set from a study concerned with an AIDS preventative intervention for Filipina sex workers.

  10. Classical and Molecular Genetic Research on General Cognitive Ability.

    PubMed

    McGue, Matt; Gottesman, Irving I

    2015-01-01

    Arguably, no psychological variable has received more attention from behavioral geneticists than what has been called "general cognitive ability" (as well as "general intelligence" or "g"), and for good reason. GCA has a rich correlational network, implying that it may play an important role in multiple domains of functioning. GCA is highly correlated with various indicators of educational attainment, yet its predictive utility is not limited to academic achievement. It is also correlated with work performance, navigating the complexities of everyday life, the absence of various social pathologies (such as criminal convictions), and even health and mortality. Although the causal basis for these associations is not always known, it is nonetheless the case that research on GCA has the potential to provide insights into the origins of a wide range of important social outcomes. In this essay, our discussion of why GCA is considered a fundamentally important dimension of behavior on which humans differ is followed by a look at behavioral genetics research on CGA. We summarize behavioral genetics research that has sought to identify and quantify the total contributions of genetic and environmental factors to individual differences in GCA as well as molecular genetic research that has sought to identify genetic variants that underlie inherited effects. © 2015 The Hastings Center.

  11. Stability of green fluorescent protein using luminescence spectroscopy: is GFP applicable to field analysis of contaminants?

    PubMed

    Smith, C B; Anderson, J E; Fischer, R L; Webb, S R

    2002-01-01

    Green fluorescent protein (GFP) was first isolated in the early 1970s for experimental use from coelenterates or the Pacific jellyfish. Aequorea victoria (Morin and Hastings, 1971). GFP has since become a favored biomarker in the photophysical analysis of molecular and cell biology because of its strong intrinsic visible fluorescence and the feasibility of fusing it to other proteins without affecting their normal functions (Creemers et al., 2000). Here we report using Bacillus subtilis expressing GFP to evaluate the influence of different environmental pH conditions on GFP fluorescence. Emission acquisitions were configured to excite at 471 nm and detect at an emission from 490 to 650 nm at 1-nm increments. Fluorescence intensity was significantly better at pH 7 (4.2 x 105 cps; P-value < 0.01) than at acid or alkaline conditions. GFP is a good biomarker for environments near netural conditions: however, GFP may be unsuitable where soils or waters are below or above pH 7 because of loss in fluorescence intensity. Alternative fluorescent markers and delivery systems must be examined in different environments to optimize responses from bioreporter molecules.

  12. Evolution and revolution as organizations grow. 1972.

    PubMed

    Greiner, L E

    1998-01-01

    The influence of history on an organization is a powerful but often overlooked force. Managers, in their haste to build companies, frequently fail to ask such critical developmental questions as, Where has our organization been? Where is it now? and What do the answers to these questions mean for where it is going? Instead, when confronted with problems, managers fix their gaze outward on the environment and toward the future, as if more precise market projections will provide the organization with a new identity. In this HBR Classic, Larry Greiner identifies a series of developmental phases that companies tend to pass through as they grow. He distinguishes the phases by their dominant themes: creativity, direction, delegation, coordination, and collaboration. Each phase begins with a period of evolution, steady growth, and stability, and ends with a revolutionary period of organizational turmoil and change. The critical task for management in each revolutionary period is to find a new set of organizational practices that will become the basis for managing the next period of evolutionary growth. Those new practices eventually outlast their usefulness and lead to another period of revolution. Managers therefore experience the irony of seeing a major solution in one period become a major problem in a later period. Originally published in 1972, the article's argument and insights remain relevant to managers today. Accompanying the original article is a commentary by the author updating his earlier observations.

  13. A consideration of the operation of automatic production machines.

    PubMed

    Hoshi, Toshiro; Sugimoto, Noboru

    2015-01-01

    At worksites, various automatic production machines are in use to release workers from muscular labor or labor in the detrimental environment. On the other hand, a large number of industrial accidents have been caused by automatic production machines. In view of this, this paper considers the operation of automatic production machines from the viewpoint of accident prevention, and points out two types of machine operation - operation for which quick performance is required (operation that is not permitted to be delayed) - and operation for which composed performance is required (operation that is not permitted to be performed in haste). These operations are distinguished by operation buttons of suitable colors and shapes. This paper shows that these characteristics are evaluated as "asymmetric on the time-axis". Here, in order for workers to accept the risk of automatic production machines, it is preconditioned in general that harm should be sufficiently small or avoidance of harm is easy. In this connection, this paper shows the possibility of facilitating the acceptance of the risk of automatic production machines by enhancing the asymmetric on the time-axis.

  14. Continuous Cotemporal Probabilistic Modeling of Systems Biology Networks from Sparse Data

    PubMed Central

    John, David J.; Fetrow, Jacquelyn S.; Norris, James L.

    2014-01-01

    Modeling of biological networks is a difficult endeavour, but exploration of this problem is essential for understanding the systems behaviour of biological processes. In this contribution, developed for sparse data, we present a new continuous Bayesian graphical learning algorithm to cotemporally model proteins in signaling networks and genes in transcriptional regulatory networks. In this continuous Bayesian algorithm the correlation matrix is singular because the number of time points is less than the number of biological entities (genes or proteins). A suitable restriction on the degree of the graph’s vertices is applied and a Metropolis-Hastings algorithm is guided by a BIC-based posterior probability score. Ten independent and diverse runs of the algorithm are conducted, so that the probability space is properly well-explored. Diagnostics to test the applicability of the algorithm to the specific data sets are developed; this is a major benefit of the methodology. This novel algorithm is applied to two time course experimental data sets: 1) protein modification data identifying a potential signaling network in chondrocytes; and 2) gene expression data identifying the transcriptional regulatory network underlying dendritic cell maturation. This method gives high estimated posterior probabilities to many of the proteins’ directed edges that are predicted by the literature; for the gene study, the method gives high posterior probabilities to many of the literature-predicted sibling edges. In simulations, the method gives substantially higher estimated posterior probabilities for true edges and true subnetworks than for their false counterparts. PMID:20855920

  15. Profile-Based LC-MS Data Alignment—A Bayesian Approach

    PubMed Central

    Tsai, Tsung-Heng; Tadesse, Mahlet G.; Wang, Yue; Ressom, Habtom W.

    2014-01-01

    A Bayesian alignment model (BAM) is proposed for alignment of liquid chromatography-mass spectrometry (LC-MS) data. BAM belongs to the category of profile-based approaches, which are composed of two major components: a prototype function and a set of mapping functions. Appropriate estimation of these functions is crucial for good alignment results. BAM uses Markov chain Monte Carlo (MCMC) methods to draw inference on the model parameters and improves on existing MCMC-based alignment methods through 1) the implementation of an efficient MCMC sampler and 2) an adaptive selection of knots. A block Metropolis-Hastings algorithm that mitigates the problem of the MCMC sampler getting stuck at local modes of the posterior distribution is used for the update of the mapping function coefficients. In addition, a stochastic search variable selection (SSVS) methodology is used to determine the number and positions of knots. We applied BAM to a simulated data set, an LC-MS proteomic data set, and two LC-MS metabolomic data sets, and compared its performance with the Bayesian hierarchical curve registration (BHCR) model, the dynamic time-warping (DTW) model, and the continuous profile model (CPM). The advantage of applying appropriate profile-based retention time correction prior to performing a feature-based approach is also demonstrated through the metabolomic data sets. PMID:23929872

  16. Modelling malaria incidence by an autoregressive distributed lag model with spatial component.

    PubMed

    Laguna, Francisco; Grillet, María Eugenia; León, José R; Ludeña, Carenne

    2017-08-01

    The influence of climatic variables on the dynamics of human malaria has been widely highlighted. Also, it is known that this mosquito-borne infection varies in space and time. However, when the data is spatially incomplete most popular spatio-temporal methods of analysis cannot be applied directly. In this paper, we develop a two step methodology to model the spatio-temporal dependence of malaria incidence on local rainfall, temperature, and humidity as well as the regional sea surface temperatures (SST) in the northern coast of Venezuela. First, we fit an autoregressive distributed lag model (ARDL) to the weekly data, and then, we adjust a linear separable spacial vectorial autoregressive model (VAR) to the residuals of the ARDL. Finally, the model parameters are tuned using a Markov Chain Monte Carlo (MCMC) procedure derived from the Metropolis-Hastings algorithm. Our results show that the best model to account for the variations of malaria incidence from 2001 to 2008 in 10 endemic Municipalities in North-Eastern Venezuela is a logit model that included the accumulated local precipitation in combination with the local maximum temperature of the preceding month as positive regressors. Additionally, we show that although malaria dynamics is highly heterogeneous in space, a detailed analysis of the estimated spatial parameters in our model yield important insights regarding the joint behavior of the disease incidence across the different counties in our study. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Geothermal Energy Production from Oil/Gas Wells and Application for Building Cooling

    SciTech Connect

    Wang, Honggang; Liu, Xiaobing

    2016-01-01

    One significant source of low-temperature geothermal energy is the coproduced hot water from oil/gas field production. In the United States, daily oil production has reached above 8 million barrels in recent years. Considering various conditions of wells, 5-10 times or more water can be coproduced in the range of temperature 120 F to 300 F. Like other geothermal resources, such energy source from oil/gas wells is under-utilized for its typical long distance from consumption sites. Many oil/gas fields, however, are relatively close (less than 10 miles) to consumers around cities. For instance, some petroleum fields in Pennsylvania are only a few miles away from the towns in Pittsburg area and some fields in Texas are quite close to Houston. In this paper, we evaluate geothermal potential from oil/gas wells by conducting numerical simulation and analysis of a fractured oil well in Hastings West field, Texas. The results suggest that hot water can be continuously coproduced from oil wells at a sufficient rate (about 4000 gallons/day from one well) for more than 100 years. Viable use of such geothermal source requires economical transportation of energy to consumers. The recently proposed two-step geothermal absorption (TSGA) system provides a promising energy transport technology that allows large-scale use of geothermal energy from thousands of oil/gas wells.

  18. Permanence in an intraguild predation model with prey switching.

    PubMed

    Zabalo, Joaquin

    2012-09-01

    Intraguild predation, a form of omnivory that can occur in simple food webs when one species preys on and competes for limiting resources with another species, can have either a stabilizing effect (McCann and Hastings in Proc. R. Soc. Lond. B 264:1249-1254, 1997) or a destabilizing effect (Holt and Polis in Am. Nat. 149:745-764, 1997), depending on the assumptions of the system. Another type of behavior that has been observed in simple food web experiments (Murdoch in Ecol. Monogr. 39:335-354, 1969) is prey switching. Prey switching can occur when the predator prefers the most abundant prey. This has also been shown to be capable of having either a stabilizing effect or a destabilizing effect and even possibly lead to predator extinction (VanLeeuwen et al. in Ecology 88:1571-1581, 2007). Therefore, it is clear that incorporating prey switching into an intraguild predation model could lead to unexpected consequences. In this paper, we propose and explore such a model.

  19. MR0175 -- A history and development study

    SciTech Connect

    Patrick, D.H.

    1999-07-01

    MR0175 is a NACE Materials Requirement that became an industry standard for Christmas Tree Valves in 1975. NACE altered MR0175 in 1978 to include other types of oil and gas production and completion equipment. Failures drove the early work and a disaster drove the 1978 version's development and the haste that NACE used to finish and publish the 1978 document. The paper traces events and documents that predate MR0175 and that the oil and gas industry used to develop and write MR0175. The paper will discuss some of the circumstances that led to MR0175's format, wording and ambiguities. The paper attempts to convey what ideas the writers were trying to express. The paper discusses the portion of the industry and the types of equipment that MR0175 addressed--the philosophy scope. The paper takes up the original intent behind MR0175 and follows its application into other areas that MR0175 did not envision. The paper covers some of the current changes that are being made to MR0175. NACE Unit Committee T-1F is also working on a major possible revision in how MR0175 speaks to CRAS (Corrosion Resistant Alloys); the paper summarizes those possibilities. The paper attempts to differentiate between what MR0175 addresses and what the International Standards Organization (ISO) sour gas document is addressing through ISO/TC67/WG7.

  20. Effect of mean flow on the analysis of noise and vibration in hydraulic lines

    NASA Astrophysics Data System (ADS)

    Hastings, Mardi C.

    2002-05-01

    Recent reports in the literature conclude that convective terms due to mean flow should be included in the analysis to predict noise and vibration in steel hydraulic lines containing compliant hoses [M. L. Munjal and P. T. Thawani, Noise Control Eng. J. 45, 235-242 (1997)]. In this study analytical predictions for noise and vibration were compared with experimental data obtained from a transmission line excited by a 10-vane pump source. The predictions were based on a transfer matrix analysis that included the fluid-structure interaction but neglected the convective terms associated with mean flow [M. C. Hastings and C.-C. Chen, J. Passenger Cars, SAE Trans. 102, 1762-1767 (1994)]. Experimental data and analytical predictions were in excellent agreement. These results indicate that mean flow convective terms are negligible and do not need to be included in the analysis of noise and vibration occurring in relatively low-power hydraulic assist systems (such as automotive power steering). A comparison of analytical results with and without mean flow convective terms for higher-power hydraulic systems indicates when the convective terms are needed for an accurate prediction of noise and vibration.

  1. Learn-as-you-go acceleration of cosmological parameter estimates

    SciTech Connect

    Aslanyan, Grigor; Easther, Richard; Price, Layne C. E-mail: r.easther@auckland.ac.nz

    2015-09-01

    Cosmological analyses can be accelerated by approximating slow calculations using a training set, which is either precomputed or generated dynamically. However, this approach is only safe if the approximations are well understood and controlled. This paper surveys issues associated with the use of machine-learning based emulation strategies for accelerating cosmological parameter estimation. We describe a learn-as-you-go algorithm that is implemented in the Cosmo++ code and (1) trains the emulator while simultaneously estimating posterior probabilities; (2) identifies unreliable estimates, computing the exact numerical likelihoods if necessary; and (3) progressively learns and updates the error model as the calculation progresses. We explicitly describe and model the emulation error and show how this can be propagated into the posterior probabilities. We apply these techniques to the Planck likelihood and the calculation of ΛCDM posterior probabilities. The computation is significantly accelerated without a pre-defined training set and uncertainties in the posterior probabilities are subdominant to statistical fluctuations. We have obtained a speedup factor of 6.5 for Metropolis-Hastings and 3.5 for nested sampling. Finally, we discuss the general requirements for a credible error model and show how to update them on-the-fly.

  2. A multivariate Poisson-lognormal regression model for prediction of crash counts by severity, using Bayesian methods.

    PubMed

    Ma, Jianming; Kockelman, Kara M; Damien, Paul

    2008-05-01

    Numerous efforts have been devoted to investigating crash occurrence as related to roadway design features, environmental factors and traffic conditions. However, most of the research has relied on univariate count models; that is, traffic crash counts at different levels of severity are estimated separately, which may neglect shared information in unobserved error terms, reduce efficiency in parameter estimates, and lead to potential biases in sample databases. This paper offers a multivariate Poisson-lognormal (MVPLN) specification that simultaneously models crash counts by injury severity. The MVPLN specification allows for a more general correlation structure as well as overdispersion. This approach addresses several questions that are difficult to answer when estimating crash counts separately. Thanks to recent advances in crash modeling and Bayesian statistics, parameter estimation is done within the Bayesian paradigm, using a Gibbs Sampler and the Metropolis-Hastings (M-H) algorithms for crashes on Washington State rural two-lane highways. Estimation results from the MVPLN approach show statistically significant correlations between crash counts at different levels of injury severity. The non-zero diagonal elements suggest overdispersion in crash counts at all levels of severity. The results lend themselves to several recommendations for highway safety treatments and design policies. For example, wide lanes and shoulders are key for reducing crash frequencies, as are longer vertical curves.

  3. Identity or Behavior: A Moral and Medical Basis for LGBTQ Rights.

    PubMed

    Solomon, Andrew

    2014-09-01

    The progress of lesbian, gay, bisexual, transsexual, and queer rights entails the erosion of prejudice, and erosion is a slow process. Much press accrues to the dramatic advancement of gay marriage, but that progress reflects decades of committed activism that antedate the sea change. Social science, physical science, politics, philosophy, religion, and innumerable other fields have bearing on the emergence of healthy LGBTQ identities. The field of bioethics is implicated both in revolutionizing attitudes and in determining how best to utilize such ameliorated positions. For decades, the debate around homosexuality has centered on whether it is a choice or an inherent quality. A growing segment of the population believes that gay people are "made that way" and therefore do not deserve to be treated with the prejudice they might warrant if they had simply elected what others resisted. In effect, they are like disabled people, who can't help the challenges they face, and unlike murderers, who could choose not to kill. Anti-gay arguments tend to hinge on a view of gayness as a behavior; the liberatory ones, on gayness as an identity. A behavior can be avoided; an identity is integral and therefore warrants acceptance-or even celebration. People have a right to their identities, even if they have the capacity to act out other, different identities. Bioethics is the field in which this distinction between gay acts and a gay self may be argued most directly. © 2014 by The Hastings Center.

  4. Performance of Thermal Mass Flow Meters in a Variable Gravitational Environment

    NASA Technical Reports Server (NTRS)

    Brooker, John E.; Ruff, Gary A.

    2004-01-01

    The performance of five thermal mass flow meters, MKS Instruments 179A and 258C, Unit Instruments UFM-8100, Sierra Instruments 830L, and Hastings Instruments HFM-200, were tested on the KC-135 Reduced Gravity Aircraft in orthogonal, coparallel, and counterparallel orientations relative to gravity. Data was taken throughout the parabolic trajectory where the g-level varied from 0.01 to 1.8 times normal gravity. Each meter was calibrated in normal gravity in the orthogonal position prior to flight followed by ground testing at seven different flow conditions to establish a baseline operation. During the tests, the actual flow rate was measured independently using choked-flow orifices. Gravitational acceleration and attitude had a unique effect on the performance of each meter. All meters operated within acceptable limits at all gravity levels in the calibrated orthogonal position. However, when operated in other orientations, the deviations from the reference flow became substantial for several of the flow meters. Data analysis indicated that the greatest source of error was the effect of orientation, followed by the gravity level. This work emphasized that when operating thermal flow meters in a variable gravity environment, it is critical to orient the meter in the same direction relative to gravity in which it was calibrated. Unfortunately, there was no test in normal gravity that could predict the performance of a meter in reduced gravity. When operating in reduced gravity, all meters indicated within 5 percent of the full scale reading at all flow conditions and orientations.

  5. Bayesian analysis of the flutter margin method in aeroelasticity

    SciTech Connect

    Khalil, Mohammad; Poirel, Dominique; Sarkar, Abhijit

    2016-08-27

    A Bayesian statistical framework is presented for Zimmerman and Weissenburger flutter margin method which considers the uncertainties in aeroelastic modal parameters. The proposed methodology overcomes the limitations of the previously developed least-square based estimation technique which relies on the Gaussian approximation of the flutter margin probability density function (pdf). Using the measured free-decay responses at subcritical (preflutter) airspeeds, the joint non-Gaussain posterior pdf of the modal parameters is sampled using the Metropolis–Hastings (MH) Markov chain Monte Carlo (MCMC) algorithm. The posterior MCMC samples of the modal parameters are then used to obtain the flutter margin pdfs and finally the flutter speed pdf. The usefulness of the Bayesian flutter margin method is demonstrated using synthetic data generated from a two-degree-of-freedom pitch-plunge aeroelastic model. The robustness of the statistical framework is demonstrated using different sets of measurement data. In conclusion, it will be shown that the probabilistic (Bayesian) approach reduces the number of test points required in providing a flutter speed estimate for a given accuracy and precision.

  6. Bayesian analysis of the flutter margin method in aeroelasticity

    DOE PAGES

    Khalil, Mohammad; Poirel, Dominique; Sarkar, Abhijit

    2016-08-27

    A Bayesian statistical framework is presented for Zimmerman and Weissenburger flutter margin method which considers the uncertainties in aeroelastic modal parameters. The proposed methodology overcomes the limitations of the previously developed least-square based estimation technique which relies on the Gaussian approximation of the flutter margin probability density function (pdf). Using the measured free-decay responses at subcritical (preflutter) airspeeds, the joint non-Gaussain posterior pdf of the modal parameters is sampled using the Metropolis–Hastings (MH) Markov chain Monte Carlo (MCMC) algorithm. The posterior MCMC samples of the modal parameters are then used to obtain the flutter margin pdfs and finally the fluttermore » speed pdf. The usefulness of the Bayesian flutter margin method is demonstrated using synthetic data generated from a two-degree-of-freedom pitch-plunge aeroelastic model. The robustness of the statistical framework is demonstrated using different sets of measurement data. In conclusion, it will be shown that the probabilistic (Bayesian) approach reduces the number of test points required in providing a flutter speed estimate for a given accuracy and precision.« less

  7. The Manhattan Frame Model - Manhattan World Inference in the Space of Surface Normals.

    PubMed

    Straub, Julian; Freifeld, Oren; Rosman, Guy; Leonard, John J; Fisher, John W

    2017-02-01

    Objects and structures within man-made environments typically exhibit a high degree of organization in the form of orthogonal and parallel planes. Traditional approaches utilize these regularities via the restrictive, and rather local, Manhattan World (MW) assumption which posits that every plane is perpendicular to one of the axes of a single coordinate system. The aforementioned regularities are especially evident in the surface normal distribution of a scene where they manifest as orthogonally-coupled clusters. This motivates the introduction of the Manhattan-Frame (MF) model which captures the notion of a MW in the surface normals space, the unit sphere, and two probabilistic MF models over this space. First, for a single MF we propose novel real-time MAP inference algorithms, evaluate their performance and their use in drift-free rotation estimation. Second, to capture the complexity of real-world scenes at a global scale, we extend the MF model to a probabilistic mixture of Manhattan Frames (MMF). For MMF inference we propose a simple MAP inference algorithm and an adaptive Markov-Chain Monte-Carlo sampling algorithm with Metropolis-Hastings split/merge moves that let us infer the unknown number of mixture components. We demonstrate the versatility of the MMF model and inference algorithm across several scales of man-made environments.

  8. Exact sampling of the unobserved covariates in Bayesian spline models for measurement error problems.

    PubMed

    Bhadra, Anindya; Carroll, Raymond J

    2016-07-01

    In truncated polynomial spline or B-spline models where the covariates are measured with error, a fully Bayesian approach to model fitting requires the covariates and model parameters to be sampled at every Markov chain Monte Carlo iteration. Sampling the unobserved covariates poses a major computational problem and usually Gibbs sampling is not possible. This forces the practitioner to use a Metropolis-Hastings step which might suffer from unacceptable performance due to poor mixing and might require careful tuning. In this article we show for the cases of truncated polynomial spline or B-spline models of degree equal to one, the complete conditional distribution of the covariates measured with error is available explicitly as a mixture of double-truncated normals, thereby enabling a Gibbs sampling scheme. We demonstrate via a simulation study that our technique performs favorably in terms of computational efficiency and statistical performance. Our results indicate up to 62 and 54 % increase in mean integrated squared error efficiency when compared to existing alternatives while using truncated polynomial splines and B-splines respectively. Furthermore, there is evidence that the gain in efficiency increases with the measurement error variance, indicating the proposed method is a particularly valuable tool for challenging applications that present high measurement error. We conclude with a demonstration on a nutritional epidemiology data set from the NIH-AARP study and by pointing out some possible extensions of the current work.

  9. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-09-27

    Dinosaur tracker Ray Stanford describes the cretaceous-era nodosaur track he found on the Goddard Space Flight Center campus with Dr. Robert Weems, emeritus paleontologist for the USGS who verified his discovery. This imprint shows the right rear foot of a nodosaur - a low-slung, spiny leaf-eater - apparently moving in haste as the heel did not fully settle in the cretaceous mud, according to dinosaur tracker Ray Stanford. It was found recently on NASA's Goddard Space Flight Center campus and is being preserved for study. To read more go to: 1.usa.gov/P9NYg7 Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  10. Assessment of burden of virus agents in an urban sewage treatment plant in Rio de Janeiro, Brazil.

    PubMed

    Fumian, Tulio Machado; Vieira, Carmen Baur; Leite, José Paulo Gagliardi; Miagostovich, Marize Pereira

    2013-03-01

    Sewage discharge is considered to be the main source of virus contamination in aquatic environments. There is no correlation between the presence of viruses and the presence of fecal coliforms in water; therefore virological markers are needed when monitoring contamination. This study investigates DNA and RNA virus concentrations in wastewater and evaluates a potential virus marker of human contamination. Influent and effluent samples were collected twice a month throughout a 1-year period. Viruses were detected using quantitative polymerase chain reaction protocols; nucleotide sequencing was carried out for virus genotyping. Human adenovirus (HAdV) and polyomavirus JC (JCPyV) were the most prevalent viruses found in influent samples (100%) with a virus load that ranged from 10(6) to 10(5) genome copies per liter (gc l(-1)). Norovirus genogroup II (NoV GII) and human astrovirus (HAstV) were less prevalent, and ranged from 10(4) to 10(3)gc l(-1). Quantitative data on virus profiles in wastewaters stress the high level of rotavirus species A environmental dissemination and address the potential of HAdV as a useful virological marker of virus contamination in aquatic environments. This study corroborates other studies performed in developed countries on DNA viruses as good markers of human fecal contamination.

  11. Exploring equivalence domain in nonlinear inverse problems using Covariance Matrix Adaption Evolution Strategy (CMAES) and random sampling

    NASA Astrophysics Data System (ADS)

    Grayver, Alexander V.; Kuvshinov, Alexey V.

    2016-05-01

    This paper presents a methodology to sample equivalence domain (ED) in nonlinear partial differential equation (PDE)-constrained inverse problems. For this purpose, we first applied state-of-the-art stochastic optimization algorithm called Covariance Matrix Adaptation Evolution Strategy (CMAES) to identify low-misfit regions of the model space. These regions were then randomly sampled to create an ensemble of equivalent models and quantify uncertainty. CMAES is aimed at exploring model space globally and is robust on very ill-conditioned problems. We show that the number of iterations required to converge grows at a moderate rate with respect to number of unknowns and the algorithm is embarrassingly parallel. We formulated the problem by using the generalized Gaussian distribution. This enabled us to seamlessly use arbitrary norms for residual and regularization terms. We show that various regularization norms facilitate studying different classes of equivalent solutions. We further show how performance of the standard Metropolis-Hastings Markov chain Monte Carlo algorithm can be substantially improved by using information CMAES provides. This methodology was tested by using individual and joint inversions of magneotelluric, controlled-source electromagnetic (EM) and global EM induction data.

  12. Preventable anesthesia mishaps: a study of human factors*

    PubMed Central

    Cooper, J.; Newbower, R.; Long, C.; McPeek, B.

    2002-01-01

    

 A modified critical-incident analysis technique was used in a retrospective examination of the characteristics of human error and equipment failure in anesthetic practice. The objective was to uncover patterns of frequently occurring incidents that are in need of careful prospective investigation. Forty seven interviews were conducted with staff and resident anesthesiologists at one urban teaching institution, and descriptions of 359 preventable incidents were obtained. Twenty three categories of details from these descriptions were subjected to computer-aided analysis for trends and patterns. Most of the preventable incidents involved human error (82%), with breathing-circuit disconnections, inadvertent changes in gas flow, and drug syringe errors being frequent problems. Overt equipment failures constituted only 14% of the total number of preventable incidents, but equipment design was indictable in many categories of human error, as were inadequate experience and insufficient familiarity with equipment or with the specific surgical procedure. Other factors frequently associated with incidents were inadequate communication among personnel, haste or lack of precaution, and distraction. Results from multi-hospital studies based on the methodology developed could be used for more objective determination of priorities and planning of specific investments for decreasing the risk associated with anesthesia. PMID:12486995

  13. Bayesian adaptive Markov chain Monte Carlo estimation of genetic parameters.

    PubMed

    Mathew, B; Bauer, A M; Koistinen, P; Reetz, T C; Léon, J; Sillanpää, M J

    2012-10-01

    Accurate and fast estimation of genetic parameters that underlie quantitative traits using mixed linear models with additive and dominance effects is of great importance in both natural and breeding populations. Here, we propose a new fast adaptive Markov chain Monte Carlo (MCMC) sampling algorithm for the estimation of genetic parameters in the linear mixed model with several random effects. In the learning phase of our algorithm, we use the hybrid Gibbs sampler to learn the covariance structure of the variance components. In the second phase of the algorithm, we use this covariance structure to formulate an effective proposal distribution for a Metropolis-Hastings algorithm, which uses a likelihood function in which the random effects have been integrated out. Compared with the hybrid Gibbs sampler, the new algorithm had better mixing properties and was approximately twice as fast to run. Our new algorithm was able to detect different modes in the posterior distribution. In addition, the posterior mode estimates from the adaptive MCMC method were close to the REML (residual maximum likelihood) estimates. Moreover, our exponential prior for inverse variance components was vague and enabled the estimated mode of the posterior variance to be practically zero, which was in agreement with the support from the likelihood (in the case of no dominance). The method performance is illustrated using simulated data sets with replicates and field data in barley.

  14. Automatic Iceball Segmentation With Adapted Shape Priors for MRI-Guided Cryoablation

    PubMed Central

    Liu, Xinyang; Tuncali, Kemal; Wells, William M.; Zientara, Gary P.

    2014-01-01

    Purpose To develop and evaluate an automatic segmentation method that extracts the 3D configuration of the ablation zone, the iceball, from images acquired during the freezing phase of MRI-guided cryoablation. Materials and Methods Intraprocedural images at 63 timepoints from 13 kidney tumor cryoablation procedures were examined retrospectively. The images were obtained using a 3 Tesla wide-bore MRI scanner and axial HASTE sequence. Initialized with semiautomatically localized cryoprobes, the iceball was segmented automatically at each timepoint using the graph cut (GC) technique with adapted shape priors. Results The average Dice Similarity Coefficients (DSC), compared with manual segmentations, were 0.88, 0.92, 0.92, 0.93, and 0.93 at 3, 6, 9, 12, and 15 min time-points, respectively, and the average DSC of the total 63 segmentations was 0.92 ± 0.03. The proposed method improved the accuracy significantly compared with the approach without shape prior adaptation (P = 0.026). The number of probes involved in the procedure had no apparent influence on the segmentation results using our technique. The average computation time was 20 s, which was compatible with an intraprocedural setting. Conclusion Our automatic iceball segmentation method demonstrated high accuracy and robustness for practical use in monitoring the progress of MRI-guided cryoablation. PMID:24338961

  15. Are gay and lesbian people fading into the history of bioethics?

    PubMed

    Murphy, Timothy F

    2014-09-01

    In many ways, we live in propitious times for gay and lesbian people. In 1996, the Supreme Court struck down Colorado law prohibiting any kind of protected status based on sexual orientation. In 2003, the Supreme Court held that states may not criminalize sexual conduct between consenting adults of the same sex in private, so long as no money changes hands. In 2010, the Congress repealed the "Don't Ask, Don't Tell" policy that excluded openly gay men and lesbians from military service. In 2013, the Supreme Court struck down key elements of the Defense of Marriage Act that prohibited any federal recognition of same-sex marriage. Most states do not allow same-sex marriage, but more and more states are joining the fold. Likewise, most U.S. states do not forbid discrimination based on sexual orientation, but the number that does is increasing. Arguably, no other social minority has made as much legal progress in so short a time. Despite these advances, the story of gay and lesbian people and the law is not yet finished, and the meaning of homosexuality for bioethics is still being written too. Concerns about gay and lesbian people remain important to bioethics in key domains, especially in seeing to the conferral of optimal health care benefits and in sorting through the priorities and social effects of research. Progress in these domains still involves lifting certain burdens of medical and social misjudgments about same-sex attraction. © 2014 by The Hastings Center.

  16. Emergency medical services public health implications and interim guidance for the Ebola virus in the United States.

    PubMed

    McCoy, Christopher E; Lotfipour, Shahram; Chakravarthy, Bharath; Schultz, Carl; Barton, Erik

    2014-11-01

    The 25th known outbreak of the Ebola Virus Disease (EVD) is now a global public health emergency and the World Health Organization (WHO) has declared the epidemic to be a Public Health Emergency of International Concern (PHEIC). Since the first cases of the West African epidemic were reported in March 2014, there has been an increase in infection rates of over 13,000% over a 6-month period. The Ebola virus has now arrived in the United States and public health professionals, doctors, hospitals, Emergency Medial Services Administrators, Medical Directors, and policy makers have been working with haste to develop strategies to prevent the disease from reaching epidemic proportions. Prehospital care providers (emergency medical technicians and paramedics) and medical first responders (including but not limited to firefighters and law enforcement) are the healthcare systems front lines when it comes to first medical contact with patients outside of the hospital setting. Risk of contracting Ebola can be particularly high in this population of first responders if the appropriate precautions are not implemented. This article provides a brief clinical overview of the Ebola Virus Disease and provides a comprehensive summary of the Center for Disease Control and Prevention's Interim Guidance for Emergency Medical Services (EMS) Systems and 9-1-1 Public Safety Answering Points (PSAPS) for Management of Patients with Known of Suspected Ebola Virus Disease in the United States.

  17. A Good Death.

    PubMed

    Powell, Tia; Hulkower, Adira

    2017-01-01

    A good death is hard to find. Family members tell us that loved ones die in the wrong place-the hospital-and do not receive high-quality care at the end of life. This issue of the Hastings Center Report offers two articles from authors who strive to provide good end-of-life care and to prevent needless suffering. We agree with their goals, but we have substantial reservations about the approaches they recommend. Respect for the decisions of patients and their surrogates is a relatively new and still vulnerable aspect of medical care. For thousands of years, patients and surrogates had no say in medical decision-making. Today, standards support shared decision-making, but these articles both carve out exceptions to those standards, limiting the rights of patients and families in decisions about specific end-of-life treatments. As bioethics consultants in an acute care setting, we frequently confront conflicts similar to those described by Jeffrey Berger and by Ellen Robinson and colleagues. In such cases, our service emphasizes redoubled efforts at communication and mediation. Focusing on goals and values, rather than interventions, produces the best possible collaboration in health care decision-making. Cases in which we would overturn a surrogate's recommendations regarding palliative sedation or do-not-resuscitate orders are rare and require careful processes and clear evidence that the surrogate's choice is contrary to patient values.

  18. Local perturbations perturb—exponentially–locally

    SciTech Connect

    De Roeck, W. Schütz, M.

    2015-06-15

    We elaborate on the principle that for gapped quantum spin systems with local interaction, “local perturbations [in the Hamiltonian] perturb locally [the groundstate].” This principle was established by Bachmann et al. [Commun. Math. Phys. 309, 835–871 (2012)], relying on the “spectral flow technique” or “quasi-adiabatic continuation” [M. B. Hastings, Phys. Rev. B 69, 104431 (2004)] to obtain locality estimates with sub-exponential decay in the distance to the spatial support of the perturbation. We use ideas of Hamza et al. [J. Math. Phys. 50, 095213 (2009)] to obtain similarly a transformation between gapped eigenvectors and their perturbations that is local with exponential decay. This allows to improve locality bounds on the effect of perturbations on the low lying states in certain gapped models with a unique “bulk ground state” or “topological quantum order.” We also give some estimate on the exponential decay of correlations in models with impurities where some relevant correlations decay faster than one would naively infer from the global gap of the system, as one also expects in disordered systems with a localized groundstate.

  19. The Declaration of Hawaii and Clarence Blomquist.

    PubMed

    Ottosson, J O

    2000-01-01

    The international code of ethics of psychiatry, the Declaration of Hawaii was in the main the achievement of Clarence Blomquist. There were several prerequisites for the success of this work. 1. The unique profile of the education of Clarence Blomquist, combining training to be a specialist in psychiatry with a doctor's degree in practical philosophy. 2. An outstanding competence in analyzing complicated issues and in putting thoughts into words. 3. The courage to challenge the Hippocratic ethics and adapt the principles of ethics to modern health care. 4. A scholarship at the Institute of Society, Ethics and the Life Sciences, Hastings-on-Hudson, New York, where he could test his ideas in an intellectual interdisciplinary atmosphere. 5. Support from the late Professor Leo Eitinger, Norway and Professor Gerdt Wretmark, Sweden, who together with Clarence Blomquist constituted a task force on ethics of the World Psychiatric Association. 6. A continuous backing-up by Dr Denis Leigh, the then secretary general of the World Psychiatric Association. Denis Leigh was convinced that a code of ethics was the only means to reconcile the various member countries on issues of misuse of psychiatry and, in addition, would raise the quality of psychiatric care throughout the world.

  20. Alternative Test Methods for Electronic Parts

    NASA Technical Reports Server (NTRS)

    Plante, Jeannette

    2004-01-01

    It is common practice within NASA to test electronic parts at the manufacturing lot level to demonstrate, statistically, that parts from the lot tested will not fail in service using generic application conditions. The test methods and the generic application conditions used have been developed over the years through cooperation between NASA, DoD, and industry in order to establish a common set of standard practices. These common practices, found in MIL-STD-883, MIL-STD-750, military part specifications, EEE-INST-002, and other guidelines are preferred because they are considered to be effective and repeatable and their results are usually straightforward to interpret. These practices can sometimes be unavailable to some NASA projects due to special application conditions that must be addressed, such as schedule constraints, cost constraints, logistical constraints, or advances in the technology that make the historical standards an inappropriate choice for establishing part performance and reliability. Alternate methods have begun to emerge and to be used by NASA programs to test parts individually or as part of a system, especially when standard lot tests cannot be applied. Four alternate screening methods will be discussed in this paper: Highly accelerated life test (HALT), forward voltage drop tests for evaluating wire-bond integrity, burn-in options during or after highly accelerated stress test (HAST), and board-level qualification.

  1. Modeling and simulation of cascading contingencies

    NASA Astrophysics Data System (ADS)

    Zhang, Jianfeng

    This dissertation proposes a new approach to model and study cascading contingencies in large power systems. The most important contribution of the work involves the development and validation of a heuristic analytic model to assess the likelihood of cascading contingencies, and the development and validation of a uniform search strategy. We model the probability of cascading contingencies as a function of power flow and power flow changes. Utilizing logistic regression, the proposed model is calibrated using real industry data. This dissertation analyzes random search strategies for Monte Carlo simulations and proposes a new uniform search strategy based on the Metropolis-Hastings Algorithm. The proposed search strategy is capable of selecting the most significant cascading contingencies, and it is capable of constructing an unbiased estimator to provide a measure of system security. This dissertation makes it possible to reasonably quantify system security and justify security operations when economic concerns conflict with reliability concerns in the new competitive power market environment. It can also provide guidance to system operators about actions that may be taken to reduce the risk of major system blackouts. Various applications can be developed to take advantage of the quantitative security measures provided in this dissertation.

  2. Projection of mesothelioma mortality in Britain using Bayesian methods

    PubMed Central

    Tan, E; Warren, N; Darnton, A J; Hodgson, J T

    2010-01-01

    Background: Mesothelioma mortality has increased more than ten-fold over the past 40 years in Great Britain, with >1700 male deaths recorded in the British mesothelioma register in 2006. Annual mesothelioma deaths now account for >1% of all cancer deaths. A Poisson regression model based on a previous work by Hodgson et al has been fitted, which has allowed informed statistical inferences about model parameters and predictions of future mesothelioma mortality to be made. Methods: In the Poisson regression model, the mesothelioma risk of an individual depends on the average collective asbestos dose for the individual in a given year and an age-specific exposure potential. The model has been fitted to the data within a Bayesian framework using the Metropolis–Hastings algorithm, a Markov Chain Monte Carlo technique, providing credible intervals for model parameters as well as prediction intervals for the number of future cases of mortality. Results: Males were most likely to have been exposed to asbestos between the ages of 30 and 49 years, with the peak year of asbestos exposure estimated to be 1963. The estimated number of background cases was 1.08 cases per million population. Conclusion: Mortality among males is predicted to peak at approximately 2040 deaths in the year 2016, with a rapid decline thereafter. Approximately 91 000 deaths are predicted to occur from 1968 to 2050 with around 61 000 of these occurring from 2007 onwards. PMID:20628377

  3. What's the Use? Disparate Purposes of U.S. Federal Bioethics Commissions.

    PubMed

    Brian, Jenny Dyck; Cook-Deegan, Robert

    2017-05-01

    In the forty-year history of U.S. bioethics commissions, these government-sanctioned forums have often demonstrated their power to address pressing problems and to enable policy change. For example, the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research, established in 1974, left a legacy of reports that were translated into regulations and had an enormous practical impact. And the 1982 report Splicing Life, by the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research, became the basis for the National Institutes of Health's Recombinant DNA Advisory Committee as well as for the Food and Drug Administration's developing "Points to Consider" when contemplating the introduction of recombinant DNA into human beings. Some efforts of bioethics commissions, however, are not tightly connected to policy change or to outcomes directly linked to a specific report. While direct policy impact is indeed a useful metric for government bioethics commissions, it is not their only legitimate utility. For instance, bioethics commissions can also be incubators for deliberation on a hot topic, giving policy-makers time to think through options while the political heat has some time to dissipate. Or a bioethics commission may stake out a position that enables a politician to take action while not necessarily following its recommendations. © 2017 The Hastings Center.

  4. Adaptive Mixture Modelling Metropolis Methods for Bayesian Analysis of Non-linear State-Space Models.

    PubMed

    Niemi, Jarad; West, Mike

    2010-06-01

    We describe a strategy for Markov chain Monte Carlo analysis of non-linear, non-Gaussian state-space models involving batch analysis for inference on dynamic, latent state variables and fixed model parameters. The key innovation is a Metropolis-Hastings method for the time series of state variables based on sequential approximation of filtering and smoothing densities using normal mixtures. These mixtures are propagated through the non-linearities using an accurate, local mixture approximation method, and we use a regenerating procedure to deal with potential degeneracy of mixture components. This provides accurate, direct approximations to sequential filtering and retrospective smoothing distributions, and hence a useful construction of global Metropolis proposal distributions for simulation of posteriors for the set of states. This analysis is embedded within a Gibbs sampler to include uncertain fixed parameters. We give an example motivated by an application in systems biology. Supplemental materials provide an example based on a stochastic volatility model as well as MATLAB code.

  5. Deep soil carbon dynamics are driven more by soil type than by climate: a worldwide meta-analysis of radiocarbon profiles.

    PubMed

    Mathieu, Jordane A; Hatté, Christine; Balesdent, Jérôme; Parent, Éric

    2015-11-01

    The response of soil carbon dynamics to climate and land-use change will affect both the future climate and the quality of ecosystems. Deep soil carbon (>20 cm) is the primary component of the soil carbon pool, but the dynamics of deep soil carbon remain poorly understood. Therefore, radiocarbon activity (Δ14C), which is a function of the age of carbon, may help to understand the rates of soil carbon biodegradation and stabilization. We analyzed the published 14C contents in 122 profiles of mineral soil that were well distributed in most of the large world biomes, except for the boreal zone. With a multivariate extension of a linear mixed-effects model whose inference was based on the parallel combination of two algorithms, the expectation-maximization (EM) and the Metropolis-Hasting algorithms, we expressed soil Δ14C profiles as a four-parameter function of depth. The four-parameter model produced insightful predictions of soil Δ14C as dependent on depth, soil type, climate, vegetation, land-use and date of sampling (R2=0.68). Further analysis with the model showed that the age of topsoil carbon was primarily affected by climate and cultivation. By contrast, the age of deep soil carbon was affected more by soil taxa than by climate and thus illustrated the strong dependence of soil carbon dynamics on other pedologic traits such as clay content and mineralogy.

  6. HZAR: hybrid zone analysis using an R software package.

    PubMed

    Derryberry, Elizabeth P; Derryberry, Graham E; Maley, James M; Brumfield, Robb T

    2014-05-01

    We present a new software package (HZAR) that provides functions for fitting molecular genetic and morphological data from hybrid zones to classic equilibrium cline models using the Metropolis-Hastings Markov chain Monte Carlo (MCMC) algorithm. The software applies likelihood functions appropriate for different types of data, including diploid and haploid genetic markers and quantitative morphological traits. The modular design allows flexibility in fitting cline models of varying complexity. To facilitate hypothesis testing, an autofit function is included that allows automated model selection from a set of nested cline models. Cline parameter values, such as cline centre and cline width, are estimated and may be compared statistically across clines. The package is written in the R language and is available through the Comprehensive R Archive Network (CRAN; http://cran.r-project.org/). Here, we describe HZAR and demonstrate its use with a sample data set from a well-studied hybrid zone in western Panama between white-collared (Manacus candei) and golden-collared manakins (M. vitellinus). Comparisons of our results with previously published results for this hybrid zone validate the hzar software. We extend analysis of this hybrid zone by fitting additional models to molecular data where appropriate.

  7. Variational method for estimating the rate of convergence of Markov-chain Monte Carlo algorithms.

    PubMed

    Casey, Fergal P; Waterfall, Joshua J; Gutenkunst, Ryan N; Myers, Christopher R; Sethna, James P

    2008-10-01

    We demonstrate the use of a variational method to determine a quantitative lower bound on the rate of convergence of Markov chain Monte Carlo (MCMC) algorithms as a function of the target density and proposal density. The bound relies on approximating the second largest eigenvalue in the spectrum of the MCMC operator using a variational principle and the approach is applicable to problems with continuous state spaces. We apply the method to one dimensional examples with Gaussian and quartic target densities, and we contrast the performance of the random walk Metropolis-Hastings algorithm with a "smart" variant that incorporates gradient information into the trial moves, a generalization of the Metropolis adjusted Langevin algorithm. We find that the variational method agrees quite closely with numerical simulations. We also see that the smart MCMC algorithm often fails to converge geometrically in the tails of the target density except in the simplest case we examine, and even then care must be taken to choose the appropriate scaling of the deterministic and random parts of the proposed moves. Again, this calls into question the utility of smart MCMC in more complex problems. Finally, we apply the same method to approximate the rate of convergence in multidimensional Gaussian problems with and without importance sampling. There we demonstrate the necessity of importance sampling for target densities which depend on variables with a wide range of scales.

  8. Volatility modeling for IDR exchange rate through APARCH model with student-t distribution

    NASA Astrophysics Data System (ADS)

    Nugroho, Didit Budi; Susanto, Bambang

    2017-08-01

    The aim of this study is to empirically investigate the performance of APARCH(1,1) volatility model with the Student-t error distribution on five foreign currency selling rates to Indonesian rupiah (IDR), including the Swiss franc (CHF), the Euro (EUR), the British pound (GBP), Japanese yen (JPY), and the US dollar (USD). Six years daily closing rates over the period of January 2010 to December 2016 for a total number of 1722 observations have analysed. The Bayesian inference using the efficient independence chain Metropolis-Hastings and adaptive random walk Metropolis methods in the Markov chain Monte Carlo (MCMC) scheme has been applied to estimate the parameters of model. According to the DIC criterion, this study has found that the APARCH(1,1) model under Student-t distribution is a better fit than the model under normal distribution for any observed rate return series. The 95% highest posterior density interval suggested the APARCH models to model the IDR/JPY and IDR/USD volatilities. In particular, the IDR/JPY and IDR/USD data, respectively, have significant negative and positive leverage effect in the rate returns. Meanwhile, the optimal power coefficient of volatility has been found to be statistically different from 2 in adopting all rate return series, save the IDR/EUR rate return series.

  9. Earth's core and inner-core resonances from analysis of VLBI nutation and superconducting gravimeter data

    NASA Astrophysics Data System (ADS)

    Rosat, S.; Lambert, S. B.; Gattano, C.; Calvo, M.

    2017-01-01

    Geophysical parameters of the deep Earth's interior can be evaluated through the resonance effects associated with the core and inner-core wobbles on the forced nutations of the Earth's figure axis, as observed by very long baseline interferometry (VLBI), or on the diurnal tidal waves, retrieved from the time-varying surface gravity recorded by superconducting gravimeters (SGs). In this paper, we inverse for the rotational mode parameters from both techniques to retrieve geophysical parameters of the deep Earth. We analyse surface gravity data from 15 SG stations and VLBI delays accumulated over the last 35 yr. We show existing correlations between several basic Earth parameters and then decide to inverse for the rotational modes parameters. We employ a Bayesian inversion based on the Metropolis-Hastings algorithm with a Markov-chain Monte Carlo method. We obtain estimates of the free core nutation resonant period and quality factor that are consistent for both techniques. We also attempt an inversion for the free inner-core nutation (FICN) resonant period from gravity data. The most probable solution gives a period close to the annual prograde term (or S1 tide). However the 95 per cent confidence interval extends the possible values between roughly 28 and 725 d for gravity, and from 362 to 414 d from nutation data, depending on the prior bounds. The precisions of the estimated long-period nutation and respective small diurnal tidal constituents are hence not accurate enough for a correct determination of the FICN complex frequency.

  10. Earth's core and inner core resonances from analysis of VLBI nutation and superconducting gravimeter data

    NASA Astrophysics Data System (ADS)

    Rosat, S.; Lambert, S. B.; Gattano, C.; Calvo, M.

    2016-10-01

    Geophysical parameters of the deep Earth's interior can be evaluated through the resonance effects associated with the core and inner-core wobbles on the forced nutations of the Earth's figure axis, as observed by very long baseline interferometry (VLBI), or on the diurnal tidal waves, retrieved from the time-varying surface gravity recorded by superconducting gravimeters (SGs). In this paper, we inverse for the rotational mode parameters from both techniques to retrieve geophysical parameters of the deep Earth. We analyze surface gravity data from 15 SG stations and VLBI delays accumulated over the last 35 years. We show existing correlations between several basic Earth parameters and then decide to inverse for the rotational modes parameters. We employ a Bayesian inversion based on the Metropolis-Hastings algorithm with a Markov Chain Monte Carlo method. We obtain estimates of the free core nutation (FCN) resonant period and quality factor that are consistent for both techniques. We also attempt an inversion for the free inner core nutation (FICN) resonant period from gravity data. The most probable solution gives a period close to the annual prograde term (or S1 tide). However the 95% confidence interval extend the possible values between roughly 28 days and 725 days for gravity, and from 362 to 414 days from nutation data, depending on the prior bounds. The precisions of the estimated long-period nutation and respective small diurnal tidal constituents are hence not accurate enough for a correct determination of the FICN complex frequency.

  11. A Bayesian Model for the Detection of X-ray Binary Black Holes

    NASA Astrophysics Data System (ADS)

    Gopalan, Giri; Bornn, Luke; Vrtilek, Saku

    2015-01-01

    In X-ray binary systems consisting of a compact object that accretes material from an orbiting secondary star, there is no simple means to determine if the compact object is a black hole or a neutron star. To assist this process we develop a Bayesian statistical model, which makes use of the fact that X-ray binary systems appear to cluster based on their compact object type when viewed from a particular 3- dimensional coordinate system derived from spectral data. In particular we utilize a latent variable model in which the latent variables follow a Gaussian process prior, and hence we are able to induce the spatial correlation we believe exists between systems of the same type. The key parameters of this model are the probabilities that an observation comes from a black hole, a pulsar, or non-pulsing neutron star. A benefit of this approach is of a computational nature - the assumption of a prior which follows a multivariate normal distribution allows for the implementation of elliptical slice sampling for performing inference, a fast and stable alternative to standard Metropolis-Hastings or Gibbs sampling (Murray 2010). Our model is fit from 13 years worth of spectral data from 30 X-ray binary systems. Its predictive power is evidenced by the accurate prediction of system types using inferred probabilities from the aforementioned model.

  12. Primary charge separation in isolated photosystem II reaction centers

    SciTech Connect

    Seibert, M.; Toon, S.; Govindjee; O`Neil, M.P.; Wasielewski, M.R.

    1992-08-24

    Primary charge-separation in isolated bacterial reaction center (RC) complex occurs in 2.8 ps at room temperature and 0.7--1.2 ps at 10 K. Because of similarities between the bacterial and photosystem II (PSII) RCs, it has been of considerable interest to obtain analogous charge-separation rates in the higher plant system. Our previous femtosecond transient absorption studies used PSII RC material stabilized with PEG or by exchanging dodecyl maltoside (DM) for Triton in the isolation procedure. These materials gave charge-separation 1/e times of 3.0 {plus_minus} 0.6 ps at 4{degree}C and 1.4{plus_minus} 0.2 ps at 15 K based on the risetime of transient absorption kinetics at 820 nm. These values were thought to represent the time required for formation of the P680{sup +}-Pheo{sup {minus}} state. Recent results of Hastings et al. obtained at high data acquisition rates and low flash intensities, suggest that the Pheo{sup {minus}} state may form more slowly. In light of this work, we have carried out additional time domain studies of both electron transport and energy transfer phenomena in stabilized DM PSII RCs at room temperature. We used a 1-kHz repetition rate femtosecond transient absorption spectrometer with a 200 fs instrumental time resolution and compared the results with those obtained by others using frequency domain hole-burning techniques.

  13. Documenting citizenship in Medicaid: the struggle between ideology and evidence.

    PubMed

    Ku, Leighton; Pervez, Fouad

    2010-02-01

    In 2006 Congress passed, and the Centers for Medicare and Medicaid Services (CMS) rapidly issued, regulations requiring states to obtain proof of citizenship from citizens who had applied for Medicaid. This policy was framed as reducing fraud by illegal aliens to preserve benefits for citizens. In fact, evidence indicates there was no significant problem of fraud by immigrants, and the major effect of the policy was to reduce coverage of eligible citizens. This article addresses the reasons why Congress developed this policy and why CMS acted with uncharacteristic haste to implement these counterproductive policies. We note the importance of the policy's symbolic framing--that is, as establishing sanctions against illegal immigration--in congressional passage during a period of rising nativism in Congress and the nation. The regulatory actions reflected the ideological preferences of political appointees and an increasingly adversarial relationship between CMS and state agencies during this period. These haphazard regulatory actions made the policies more convoluted and likely led more eligible citizens to lose coverage. In 2009, Congress amended the law to modify implementation. These issues have continued to persist in the recent debate on national health care reform.

  14. Biochemistry of dinoflagellate bioluminescence: purification and characterization of dinoflagellate luciferin from Pyrocystis lunula.

    PubMed

    Dunlap, J C; Hastings, J W

    1981-02-17

    Bioluminescence in all dinoflagellate species studied to date is produced by the luciferase-catalyzed oxidation of a newly elucidated type of luciferin, hypothesized to have a substituted polypyrrole-type structure. This paper presents the purification and characterization of the luciferin from Pyrocystis lunula along with evidence that it is a polypyrrole-type molecule. Luciferin is extremely labile at low pH, at high salt concentration, and to O2, so, where possible, the purification steps were carried out in the presence of a buffered reducing agent and under argon. Purified luciferin is soluble in water and polar organic solvents. It is yellow (lambda max 245 and 390 nm with a shoulder at 290 nm in neutral or basic aqueous solution) and displays a strong blue fluorescence (lambda max for excitation at 390 nm, for emission at 474 nm) that closely matches the bioluminescence emission spectrum [Bode, V. C., & Hastings, J. W. (1963) Arch. Biochem. Biophys. 103, 488--499]. Autoxidation leads to concomitant decreases in the 390-nm absorbance, 474-nm fluorescence, and biological activity; similar changes occurred with oxidation by K3Fe(CN)6, thus allowing a quantitation of luciferin by titration. Luciferin has a molecular weight between 500 and 600, displays positive Ehrlich and Schlesinger reactions, and yields on acid chromate oxidation fragments apparently resembling substituted maleimides; these data support the proposal that dinoflagellate luciferin contains a substituted polypyrrole of the bile pigment type.

  15. Closed Financial Loops: When They Happen in Government, They're Called Corruption; in Medicine, They're Just a Footnote.

    PubMed

    De Jesus-Morales, Kevin; Prasad, Vinay

    2017-05-01

    Many physicians are involved in relationships that create tension between a physician's duty to work in her patients' best interest at all times and her financial arrangement with a third party, most often a pharmaceutical manufacturer, whose primary goal is maximizing sales or profit. Despite the prevalence of this threat, in the United States and globally, the most common reaction to conflicts of interest in medicine is timid acceptance. There are few calls for conflicts of interest to be banned, and, to our knowledge, no one calls for conflicted practitioners to be reprimanded. Contrast our attitudes in medicine with public attitudes toward financial conflicts among government employees. When enforcement of rules against conflict of interest slackens in the public sector, news organizations investigate and publish their criticism. Yet even when doctors are quoted in the media promoting specific drugs, their personal financial ties to the drug maker are rarely mentioned. Policies for governmental employees are strict, condemnation is strong, and criminal statutes exist (allowing for corruption charges). Yet the evidence that conflict is problematic is, if anything, stronger in medicine than in the public sector. Policies against conflicts of interest in medicine should be at least as strong as those already existing in the public sector. © 2017 The Hastings Center.

  16. Coercivity enhancement of sintered Nd-Fe-B magnets by chemical bath deposition of TbCl{sub 3}

    SciTech Connect

    Guo, Shuai Zhang, Xiaofeng; Ding, Guangfei; Chen, Renjie; Yan, Aru; Lee, Don

    2014-05-07

    The chemical bath deposition (CBD) and the grain boundary diffusion method were combined to diffuse the heavy rare earth for obtain the thick magnets with high coercivity and low heavy rare earth. The jet mill powders were soaked into the alcohol solution of 0.2 wt. % TbCl{sub 3}. A thin layer of TbCl{sub 3} was wrapped to the surface of (PrNd){sub 2}Fe{sub 14}B powder particles. The coercivity of magnet is increased from 11.89 kOe to 14.72 kOe without significant reduction of remanence after grain boundary diffusion in the sintering and the annealing processes. The temperature coefficients of the remanence and the coercivity are improved by the substitution of PrNd by Tb in the surface of grains. The highly accelerated temperature/humidity stress test (HAST) results indicate that the CBD magnet has poor corrosion resistance, attributing to the present of Cl atoms in the grain boundaries.

  17. A Comparison of Homeless Male Veterans in Metropolitan and Micropolitan Areas in Nebraska: A Methodological Caveat.

    PubMed

    Tsai, Jack; Ramaswamy, Sriram; Bhatia, Subhash C; Rosenheck, Robert A

    2015-12-01

    This study explored differences between homeless male veterans in metropolitan and micropolitan cities in Nebraska on sociodemographic, housing, clinical, and psychosocial characteristics as well as health service use. A convenience sample of 151 homeless male veterans (112 metropolitan, 39 micropolitan) were recruited from Veterans Affairs facilities and area shelters in Omaha, Lincoln, Grand Island, and Hastings in Nebraska. Research staff conducted structured interviews with homeless veterans. Results showed that compared to homeless veterans in metropolitans, those in micropolitans were more likely to be White, unmarried, living in transitional settings, and were far more transient but reported greater social support and housing satisfaction. Veterans in micropolitans also reported more medical problems, diagnoses of anxiety and personality disorders, and unexpectedly, were more likely to report using various health services and less travel time for services. Together, these findings suggest access to homeless and health services for veterans in micropolitan areas may be facilitated through Veterans Affairs facilities and community providers that work in close proximity to one another. Many homeless veterans in these areas are transient, making them a difficult population to study and serve. Innovative ways to provide outreach to homeless veterans in micropolitan and more rural areas are needed.

  18. Skew ocular deviation: a catastrophic sign on MRI of fetal glioblastoma.

    PubMed

    Chuang, Yu-Ming; Guo, Wan-Yuo; Ho, Donald Ming-Tak; Wong, Tai-Tong; Hung, Jeng-Hsiu; Chen, Shu-Jen; Sheu, Ming-Huei; Chang, Cheng-Yen

    2003-06-01

    We report the prenatal observation of fetal ocular skew deviation in a case of a glioblastoma found prenatally at 33 weeks' gestation by MRI. The fetal MRI, obtained by half-Fourier single-shot turbo spin echo (HASTE) pulse sequences, showed a tumor (80 mm in maximum diameter) in the right deep cerebral hemisphere with extension to the mid-cranial fossa and tentorial hiatus in addition to severe hydrocephalus. On coronal MR images a vertical dysconjugated gaze was recognized. One week after the MRI, frequent delayed deceleration prompted an emergency cesarean section. The baby was born with left hemiparesis and central neurogenic hyperventilation, which evolved into decerebrate rigidity and apneustic breathing within 2 h. Post-mortem examination revealed a glioblastoma in the right deep hemisphere, a tumor with brain stem involvement, and transtentorial herniation. We suggest, therefore, that recognition of ocular skew deviation on fetal MR images would indicate brain stem involvement and poor postnatal prognosis. Early recognition of the catastrophic sign would lead to proper management.

  19. Probabilistic two-dimensional water-column and seabed inversion with self-adapting parameterizations.

    PubMed

    Dettmer, Jan; Dosso, Stan E

    2013-05-01

    This paper develops a probabilistic two-dimensional (2D) inversion for geoacoustic seabed and water-column parameters in a strongly range-dependent environment. Range-dependent environments in shelf and shelf-break regions are of increasing importance to the acoustical-oceanography community, and recent advances in nonlinear inverse theory and sampling methods are applied here for efficient probabilistic range-dependent inversion. The 2D seabed and water column are parameterized using highly efficient, self-adapting irregular grids which intrinsically match the local resolving power of the data and provide parsimonious solutions requiring few parameters to capture complex environments. The self-adapting parameterization is achieved by implementing the irregular grid as a trans-dimensional hierarchical Bayesian model with an unknown number of nodes which is sampled with the Metropolis-Hastings-Green algorithm. To improve sampling, population Monte Carlo is applied with a large number of interacting parallel Markov chains with adaptive proposal distributions. The inversion is applied to simulated data for a vertical-line array and several source locations to several kilometers range. Complex acoustic-pressure fields are computed using a parabolic equation model and results are considered in terms of 2D ensemble parameter estimates and credibility intervals.

  20. Stochastic Tracking of Infection in a CF Lung

    PubMed Central

    Zarei, Sara; Mirtar, Ali; Rohwer, Forest; Salamon, Peter

    2014-01-01

    Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scan are the two ubiquitous imaging sources that physicians use to diagnose patients with Cystic Fibrosis (CF) or any other Chronic Obstructive Pulmonary Disease (COPD). Unfortunately the cost constraints limit the frequent usage of these medical imaging procedures. In addition, even though both CT scan and MRI provide mesoscopic details of a lung, in order to obtain microscopic information a very high resolution is required. Neither MRI nor CT scans provide micro level information about the location of infection in a binary tree structure the binary tree structure of the human lung. In this paper we present an algorithm that enhances the current imaging results by providing estimated micro level information concerning the location of the infection. The estimate is based on a calculation of the distribution of possible mucus blockages consistent with available information using an offline Metropolis-Hastings algorithm in combination with a real-time interpolation scheme. When supplemented with growth rates for the pockets of mucus, the algorithm can also be used to estimate how lung functionality as manifested in spirometric tests will change in patients with CF or COPD. PMID:25360611

  1. Identification of a vacuolar proton channel that triggers the bioluminescent flash in dinoflagellates

    PubMed Central

    Rodriguez, Juan D.; Haq, Saddef; Bachvaroff, Tsvetan; Nowak, Kristine F.; Nowak, Scott J.; Morgan, Deri; Cherny, Vladimir V.; Sapp, Maredith M.; Bernstein, Steven; Bolt, Andrew; DeCoursey, Thomas E.; Place, Allen R.; Smith, Susan M. E.

    2017-01-01

    In 1972, J. Woodland Hastings and colleagues predicted the existence of a proton selective channel (HV1) that opens in response to depolarizing voltage across the vacuole membrane of bioluminescent dinoflagellates and conducts protons into specialized luminescence compartments (scintillons), thereby causing a pH drop that triggers light emission. HV1 channels were subsequently identified and demonstrated to have important functions in a multitude of eukaryotic cells. Here we report a predicted protein from Lingulodinium polyedrum that displays hallmark properties of bona fide HV1, including time-dependent opening with depolarization, perfect proton selectivity, and characteristic ΔpH dependent gating. Western blotting and fluorescence confocal microscopy of isolated L. polyedrum scintillons immunostained with antibody to LpHV1 confirm LpHV1’s predicted organellar location. Proteomics analysis demonstrates that isolated scintillon preparations contain peptides that map to LpHV1. Finally, Zn2+ inhibits both LpHV1 proton current and the acid-induced flash in isolated scintillons. These results implicate LpHV1 as the voltage gated proton channel that triggers bioluminescence in L. polyedrum, confirming Hastings’ hypothesis. The same channel likely mediates the action potential that communicates the signal along the tonoplast to the scintillon. PMID:28178296

  2. An Empirical Prior Improves Accuracy for Bayesian Estimation of Transcription Factor Binding Site Frequencies within Gene Promoters

    PubMed Central

    Ramsey, Stephen A.

    2015-01-01

    A Bayesian method for sampling from the distribution of matches to a precompiled transcription factor binding site (TFBS) sequence pattern (conditioned on an observed nucleotide sequence and the sequence pattern) is described. The method takes a position frequency matrix as input for a set of representative binding sites for a transcription factor and two sets of noncoding, 5′ regulatory sequences for gene sets that are to be compared. An empirical prior on the frequency A (per base pair of gene-vicinal, noncoding DNA) of TFBSs is developed using data from the ENCODE project and incorporated into the method. In addition, a probabilistic model for binding site occurrences conditioned on λ is developed analytically, taking into account the finite-width effects of binding sites. The count of TFBS β (conditioned on the observed sequence) is sampled using Metropolis–Hastings with an information entropy-based move generator. The derivation of the method is presented in a step-by-step fashion, starting from specific conditional independence assumptions. Empirical results show that the newly proposed prior on β improves accuracy for estimating the number of TFBS within a set of promoter sequences. PMID:27812284

  3. OntoQuery: easy-to-use web-based OWL querying.

    PubMed

    Tudose, Ilinca; Hastings, Janna; Muthukrishnan, Venkatesh; Owen, Gareth; Turner, Steve; Dekker, Adriano; Kale, Namrata; Ennis, Marcus; Steinbeck, Christoph

    2013-11-15

    The Web Ontology Language (OWL) provides a sophisticated language for building complex domain ontologies and is widely used in bio-ontologies such as the Gene Ontology. The Protégé-OWL ontology editing tool provides a query facility that allows composition and execution of queries with the human-readable Manchester OWL syntax, with syntax checking and entity label lookup. No equivalent query facility such as the Protégé Description Logics (DL) query yet exists in web form. However, many users interact with bio-ontologies such as chemical entities of biological interest and the Gene Ontology using their online Web sites, within which DL-based querying functionality is not available. To address this gap, we introduce the OntoQuery web-based query utility.  The source code for this implementation together with instructions for installation is available at http://github.com/IlincaTudose/OntoQuery. OntoQuery software is fully compatible with all OWL-based ontologies and is available for download (CC-0 license). The ChEBI installation, ChEBI OntoQuery, is available at http://www.ebi.ac.uk/chebi/tools/ontoquery. hastings@ebi.ac.uk.

  4. A theoretical approach to calibrate radiation portal monitor (RPM) systems.

    PubMed

    Nafee, Sherif S; Abbas, Mahmoud I

    2008-10-01

    Radiation portal monitor (RPM) systems are widely used at international border crossings, where they are applied to the task of detecting nuclear devices, special nuclear material, and radiation dispersal device materials that could appear at borders. The requirements and constraints on RPM systems deployed at high-volume border crossings are significantly different from those at weapons facilities or steel recycling plants, the former being required to rapidly detect localized sources of radiation with a very high detection probability and low false-alarm rate, while screening all of the traffic without impeding the flow of commerce [Chambers, W.H., Atwater, H.F., Fehlau, P.E., Hastings, R.D., Henry, C.N., Kunz, W.E., Sampson, T.E., Whittlesey, T.H., Worth, G.M., 1974. Portal Monitor for Diversion Safeguards. LA-5681, Los Alamos Scientific Laboratory, Los Alamos, NM]. In the present work, compact analytical formulae are derived and used to calibrate two RPM systems with isotropic radiating sources: (i) polyvinyltoluene (PVT) or plastic and (ii) thallium-doped crystalline sodium iodide, NaI(Tl), gamma-ray detector materials. The calculated efficiencies are compared to measured values reported in the literatures, showing very good agreement.

  5. Altering risky decision-making: Influence of impulsivity on the neuromodulation of prefrontal cortex.

    PubMed

    Cheng, Gordon L F; Lee, Tatia M C

    2016-01-01

    The prefrontal cortex (PFC) subserves complex cognitive abilities, including risky decision-making; the modulation of this brain area is shown to alter the way people take risks. Yet, neuromodulation of the PFC in relation to risk-taking behavior remains relatively less well-studied. Moreover, the psychological variables that influence such neuromodulation remain poorly understood. To address these issues, 16 participants took part in 3 experimental sessions on separate days. They received: (i) left anodal-right cathodal transcranial direct current stimulation (tDCS); (ii) left cathodal-right anodal stimulation; or (iii) sham stimulation while they completed two risk-taking tasks. They also measured on several cognitive-affective abilities and personality traits. It was revealed that left cathodal-right anodal stimulation led to significantly reduced risk-taking under a context of haste. The reduction of risk-taking (relative to sham) correlated with state and trait impulsivity, such that the effect was larger in more impulsive individuals. For these individuals, the tDCS effect size was considered to be large (generalized partial η(2) > .17). The effect of prefrontal-neuromodulation in reducing risk-taking was influenced by baseline impulsivity, reflecting a state-dependent effect of neuromodulation on the PFC. The results of this study carry important insights into the use of neuromodulation to alter higher cognition.

  6. Innovative Composite Wall System for Sheathing Masonry Walls

    SciTech Connect

    Wendt, Robert L.; Cavallo, James

    1997-09-25

    Existing Housing - Much of the older multifamily housing stock in the United States includes units in structures with uninsulated masonry walls. Included in this stock are two- and three-story walk-up apartments, larger apartment complexes, and public housing (both high- rise and townhouse). This older multifamily housing has seen years of heavy use that may have left the plaster wall marred or damaged. Long- term building settlement or movement may have cracked the plaster, sometimes severely. Moisture from invented kitchens and baths may have caused condensation on uninsulated exterior walls. At best this condensation has left stains on the paint or wallpaper. At worst it has supported mold and mildew growth, fouling the air and creating unhealthy living conditions. Deteriorating plaster and flaking paint also result from wet walls. The presence of flaking, lead-based paint in older (pre-1978) housing is a major public health concern. Children can suffer permanent mental handicaps and psychological disorders if they are subjected to elevated levels of lead, while adults can suffer hypertension and other maladies. Studies have found that, in some urban communities with older housing stocks, over 35% of children tested have elevated blood lead levels (Hastings, et al.: 1997). Nationally, nearly 22% of black, non-hispanic children living in pre-1946 housing were found to have elevated levels of lead in their blood (MWWR Article: February 21,1997). The deterioration of many of these walls is to the point that lead can freely enter the living space.

  7. A coupled hidden Markov model for disease interactions

    PubMed Central

    Sherlock, Chris; Xifara, Tatiana; Telfer, Sandra; Begon, Mike

    2013-01-01

    To investigate interactions between parasite species in a host, a population of field voles was studied longitudinally, with presence or absence of six different parasites measured repeatedly. Although trapping sessions were regular, a different set of voles was caught at each session, leading to incomplete profiles for all subjects. We use a discrete time hidden Markov model for each disease with transition probabilities dependent on covariates via a set of logistic regressions. For each disease the hidden states for each of the other diseases at a given time point form part of the covariate set for the Markov transition probabilities from that time point. This allows us to gauge the influence of each parasite species on the transition probabilities for each of the other parasite species. Inference is performed via a Gibbs sampler, which cycles through each of the diseases, first using an adaptive Metropolis–Hastings step to sample from the conditional posterior of the covariate parameters for that particular disease given the hidden states for all other diseases and then sampling from the hidden states for that disease given the parameters. We find evidence for interactions between several pairs of parasites and of an acquired immune response for two of the parasites. PMID:24223436

  8. A coupled hidden Markov model for disease interactions.

    PubMed

    Sherlock, Chris; Xifara, Tatiana; Telfer, Sandra; Begon, Mike

    2013-08-01

    To investigate interactions between parasite species in a host, a population of field voles was studied longitudinally, with presence or absence of six different parasites measured repeatedly. Although trapping sessions were regular, a different set of voles was caught at each session, leading to incomplete profiles for all subjects. We use a discrete time hidden Markov model for each disease with transition probabilities dependent on covariates via a set of logistic regressions. For each disease the hidden states for each of the other diseases at a given time point form part of the covariate set for the Markov transition probabilities from that time point. This allows us to gauge the influence of each parasite species on the transition probabilities for each of the other parasite species. Inference is performed via a Gibbs sampler, which cycles through each of the diseases, first using an adaptive Metropolis-Hastings step to sample from the conditional posterior of the covariate parameters for that particular disease given the hidden states for all other diseases and then sampling from the hidden states for that disease given the parameters. We find evidence for interactions between several pairs of parasites and of an acquired immune response for two of the parasites.

  9. Imaging the propagation of shock waves with both high temporal and high spatial resolution using XFELs

    NASA Astrophysics Data System (ADS)

    Schropp, Andreas

    2013-06-01

    The emergence of x-ray sources of the fourth generation, so called x-ray free-electron lasers (XFELs), comes along with completely new research opportunities in various scientific fields. During the last year we developed an x-ray microscope based on beryllium compound refractive lenses (Be-CRLs), which is especially optimized for the XFEL environment and provides focusing capabilities down to 100nm and even below. Based on magnified x-ray phase contrast imaging, this new setup enables us to pursue high-resolution x-ray imaging experiments with single XFEL-pulses. In a first experiment, carried out at the Matter in Extreme Conditions (MEC) endstation of the LCLS, the performance of the instrument was investigated by direct imaging of shock waves in different materials. The shock wave was induced by an intense 150 ps optical laser pulse. The evolution of the shock wave was then monitored with the XFEL-beam. In this contribution we report on first analysis results of phase contrast imaging of shock waves in matter. In collaboration with Brice Arnold, Eric Galtier, Hae Ja Lee, Bob Nagler, Jerome Hastings, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., Menlo Park, CA 94025, USA; Damian Hicks, Yuan Ping, Gilbert Collins, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551, USA; and Robert Hoppe, Vivienne Meier, Jens Patommel, Frank Seiboth, Christian Schroer, Institute of Structural Physics, Technische Universität Dresden, D-01062 Dresden, Germany.

  10. The Precision Medicine Nation.

    PubMed

    Sabatello, Maya; Appelbaum, Paul S

    2017-07-01

    The United States' ambitious Precision Medicine Initiative proposes to accelerate exponentially the adoption of precision medicine, an approach to health care that tailors disease diagnosis, treatment, and prevention to individual variability in genes, environment, and lifestyle. It aims to achieve this by creating a cohort of volunteers for precision medicine research, accelerating biomedical research innovation, and adopting policies geared toward patients' empowerment. As strategies to implement the PMI are formulated, critical consideration of the initiative's ethical and sociopolitical dimensions is needed. Drawing on scholarship of nationalism and democracy, we discuss the PMI's construction of what we term "genomic citizenship"; the possible normative obligations arising therefrom; and the ethical, legal, and social challenges that will ensue. Although the PMI is a work in progress, discussion of the existing and emerging issues can facilitate the development of policies, structures, and procedures that can maximize the initiative's ability to produce equitable and socially sensitive outcomes. Our analysis can also be applied to other population-based, precision medicine research programs. © 2017 The Hastings Center.

  11. Bayesian analysis of the flutter margin method in aeroelasticity

    SciTech Connect

    Khalil, Mohammad; Poirel, Dominique; Sarkar, Abhijit

    2016-08-27

    A Bayesian statistical framework is presented for Zimmerman and Weissenburger flutter margin method which considers the uncertainties in aeroelastic modal parameters. The proposed methodology overcomes the limitations of the previously developed least-square based estimation technique which relies on the Gaussian approximation of the flutter margin probability density function (pdf). Using the measured free-decay responses at subcritical (preflutter) airspeeds, the joint non-Gaussain posterior pdf of the modal parameters is sampled using the Metropolis–Hastings (MH) Markov chain Monte Carlo (MCMC) algorithm. The posterior MCMC samples of the modal parameters are then used to obtain the flutter margin pdfs and finally the flutter speed pdf. The usefulness of the Bayesian flutter margin method is demonstrated using synthetic data generated from a two-degree-of-freedom pitch-plunge aeroelastic model. The robustness of the statistical framework is demonstrated using different sets of measurement data. In conclusion, it will be shown that the probabilistic (Bayesian) approach reduces the number of test points required in providing a flutter speed estimate for a given accuracy and precision.

  12. Orbits for the Impatient: A Bayesian Rejection-sampling Method for Quickly Fitting the Orbits of Long-period Exoplanets

    NASA Astrophysics Data System (ADS)

    Blunt, Sarah; Nielsen, Eric L.; De Rosa, Robert J.; Konopacky, Quinn M.; Ryan, Dominic; Wang, Jason J.; Pueyo, Laurent; Rameau, Julien; Marois, Christian; Marchis, Franck; Macintosh, Bruce; Graham, James R.; Duchêne, Gaspard; Schneider, Adam C.

    2017-05-01

    We describe a Bayesian rejection-sampling algorithm designed to efficiently compute posterior distributions of orbital elements for data covering short fractions of long-period exoplanet orbits. Our implementation of this method, Orbits for the Impatient (OFTI), converges up to several orders of magnitude faster than two implementations of Markov Chain Monte Carlo (MCMC) in this regime. We illustrate the efficiency of our approach by showing that OFTI calculates accurate posteriors for all existing astrometry of the exoplanet 51 Eri b up to 100 times faster than a Metropolis-Hastings MCMC. We demonstrate the accuracy of OFTI by comparing our results for several orbiting systems with those of various MCMC implementations, finding the output posteriors to be identical within shot noise. We also describe how our algorithm was used to successfully predict the location of 51 Eri b six months in the future based on less than three months of astrometry. Finally, we apply OFTI to 10 long-period exoplanets and brown dwarfs, all but one of which have been monitored over less than 3% of their orbits, producing fits to their orbits from astrometric records in the literature.

  13. Synthetic fracture network characterization with transdimensional inversion

    NASA Astrophysics Data System (ADS)

    Somogyvári, Márk; Jalali, Mohammadreza; Jimenez Parras, Santos; Bayer, Peter

    2017-06-01

    Fracture network geometry is crucial for transport in hard rock aquifers, but it can only be approximated in models. While fracture orientation, spacing, and intensity can be obtained from borehole logs, core images, and outcrops, the characterization of in situ fracture network geometry requires the interpretation of spatially distributed hydraulic and transport experiments. In this study, we present a novel concept using a transdimensional inversion method (reversible jump Markov Chain Monte Carlo, rjMCMC) to invert a two-dimensional cross-well discrete fracture network (DFN) geometry from tracer tomography experiments. The conservative tracer transport is modeled via a fast finite difference model neglecting matrix diffusion. The proposed DFN inversion method iteratively evolves DFN variants by geometry updates to fit the observed tomographic data evaluated by the Metropolis-Hastings-Green acceptance criteria. A main feature is the varying dimensions of the inverse problem, which allows for the calibration of fracture geometries and numbers. This delivers an ensemble of thousands of DFN realizations that can be utilized for probabilistic identification of fractures in the aquifer. In the presented hypothetical and outcrop-based case studies, cross sections between boreholes are investigated. The procedure successfully identifies major transport pathways in the investigated domain and explores equally probable DFN realizations, which are analyzed in fracture probability maps and by multidimensional scaling.

  14. Virtual Goods Recommendations in Virtual Worlds

    PubMed Central

    Chen, Kuan-Yu; Liao, Hsiu-Yu; Chen, Jyun-Hung; Liu, Duen-Ren

    2015-01-01

    Virtual worlds (VWs) are computer-simulated environments which allow users to create their own virtual character as an avatar. With the rapidly growing user volume in VWs, platform providers launch virtual goods in haste and stampede users to increase sales revenue. However, the rapidity of development incurs virtual unrelated items which will be difficult to remarket. It not only wastes virtual global companies' intelligence resources, but also makes it difficult for users to find suitable virtual goods fit for their virtual home in daily virtual life. In the VWs, users decorate their houses, visit others' homes, create families, host parties, and so forth. Users establish their social life circles through these activities. This research proposes a novel virtual goods recommendation method based on these social interactions. The contact strength and contact influence result from interactions with social neighbors and influence users' buying intention. Our research highlights the importance of social interactions in virtual goods recommendation. The experiment's data were retrieved from an online VW platform, and the results show that the proposed method, considering social interactions and social life circle, has better performance than existing recommendation methods. PMID:25834837

  15. A high reliability module with thermoelectric device by molding technology for M2M wireless sensor network

    NASA Astrophysics Data System (ADS)

    Nakagawa, K.; Tanaka, T.; Suzuki, T.

    2015-10-01

    This paper presents the fabrication of a new energy harvesting module that uses a thermoelectric device (TED) by using molding technology. Through molding technology, the TED and circuit board can be properly protected and a heat-radiating fin structure can be simultaneously constructed. The output voltage per heater temperature of the TED module at 20 °C ambient temperature is 8 mV K-1, similar to the result with the aluminum heat sink which is almost the same fin size as the TED module. The accelerated environmental tests are performed on a damp heat test, which is an aging test under high temperature and high humidity, highly accelerated temperature, and humidity stress test (HAST) for the purpose of evaluating the electrical reliability in harsh environments, cold test and thermal cycle test to evaluate degrading characteristics by cycling through two temperatures. All test results indicate that the TED and circuit board can be properly protected from harsh temperature and humidity by using molding technology because the output voltage of after-tested modules is reduced by less than 5%. This study presents a novel fabrication method for a high reliability TED-installed module appropriate for Machine to Machine wireless sensor networks.

  16. Progeria: pathogenesis and oral manifestation--a review.

    PubMed

    Saigal, S; Bhargava, A

    2012-01-01

    Our life span is genetically programmed and it is possible that a defect in produced proteins encoded by the longevity gene is a cause of aging. Progeria which is a rare, fatal genetic condition which affects between one in four million and one in eight million children of both sexes equally and characterized by premature and accelerated aging. The appearance and physiology of these children resembles to elderly people but they typically have life span to their mid teens. It is also known as the Hutchinson-Gilford syndrome, which was initially reported by Johnathan Hutchinson in 1886 and further described by Hastings Gilford in 1904. It is an autosomal recessive disorder, which means an individual has inherited a mutated gene from both parents. It is added to the expanding catalogue of laminopathies, diseases caused by mutations affecting nuclear lamina proteins known as lamin A (LMNA). In oral manifestation primary finding is micrognathia with delayed tooth eruption and incomplete formation of root of permanent tooth. Presently there are no known cures for this abnormality.

  17. Investigation of - and Post-Seismic Signals in GRACE Satellite Gravity Data Using Mcmc Approach

    NASA Astrophysics Data System (ADS)

    Mikhailov, V. O.; Hayn, M.; Pollitz, F. F.; Panet, I.; Holschneider, M.; Diament, M.

    2013-12-01

    Earthquakes cause mass shifts and stress-dependent density changes. The corresponding gravity field variations can be measured by the GRACE satellites what was demonstrated for recent Andaman-Sumatra (2004), Maule, Chili (2010) and Tohoku-Oki (2011) earthquakes. In contrast to other data, satellite gravity regularly covers continental and oceanic areas, providing important information about the seismic cycle, especially in subduction zones. We make use of the characteristic temporal behavior and spatial scale of the earthquake signals, in order to separate them from other contributions to the gravity field. This is realized by wavelet transform and application of a time evolution model. The later consists of a step function followed by an exponential decay, representing co- and post-seismic variations. As the problem is nonlinear, parameters were fitted by determining their posterior distribution by means of a Markov-Chain Metropolis-Hasting sampling. As a result, we clearly separate the co- and post-seismic gravity variations for all three abovementioned earthquakes. We also apply the method to separate post-seismic signals from the Andaman-Sumatra and Nias-Sumatra events. The later occurred 3 months later to the south of the main megathrust event. These results are compared with other geophysical data and models. This allows to discriminate between candidate models for the co-seismic gravity variations using GPS data and seismology, and to better understand the physical processes involved in the post-seismic deformation.

  18. A multi-thermogram-based Bayesian model for the determination of the thermal diffusivity of a material

    NASA Astrophysics Data System (ADS)

    Allard, Alexandre; Fischer, Nicolas; Ebrard, Géraldine; Hay, Bruno; Harris, Peter; Wright, Louise; Rochais, Denis; Mattout, Jeremie

    2016-02-01

    The determination of thermal diffusivity is at the heart of modern materials characterisation. The evaluation of the associated uncertainty is difficult because the determination is performed in an indirect way, in the sense that the thermal diffusivity cannot be measured directly. The well-known GUM uncertainty framework does not provide a reliable evaluation of measurement uncertainty for such inverse problems, because in that framework the underlying measurement model is supposed to be a direct relationship between the measurand (the quantity intended to be measured) and the input quantities on which the measurand depends. This paper is concerned with the development of a Bayesian approach to evaluate the measurement uncertainty associated with thermal diffusivity. A Bayesian model is first developed for a single thermogram and is then extended to the case of several thermograms obtained under repeatability and reproducibility conditions. This multi-thermogram based model is able to take into consideration a large set of influencing quantities that occur during the measurements and yields a more reliable uncertainty evaluation than the one obtained from a single thermogram. Different aspects of the Bayesian model are discussed, including the sensitivity to the choice of the prior distribution, the Metropolis-Hastings algorithm used for the inference and the convergence of the Markov chains.

  19. Can Genetics Research Benefit Educational Interventions for All?

    PubMed

    Asbury, Kathryn

    2015-01-01

    Pretty much everyone knows that our genes have at least something to do with how able or how high achieving we are. Some believe that we should not speak of this common knowledge, nor inquire into how genetic influence works or what it might mean. If we do not keep an open mind to the fact of genetic influence on academic achievement, however, then we cannot explore its possible implications. And if we do not consider the implications, then we cannot, as a society, harness any potential benefits or avoid possible pitfalls. So that's what this essay is about-exploring what behavioral genetics research might be able to offer to educational theory, policy, and practice. We cannot yet use biological information to make accurate predictions for all children. We do know, however, that academic achievement is heritable, which is to say that differences between individuals are influenced by differences in their DNA. If genes are part of the problem for some pupils (to take the negative spin on this), then it seems likely that studying them could be part of a solution. And that's what behavioral geneticists are trying to do-to chart and understand pathways from DNA to behavior and to identify interventions that can maximize outcomes for all. The fact is, though, that we have an awfully long way to go. © 2015 The Hastings Center.

  20. A consideration of the operation of automatic production machines

    PubMed Central

    HOSHI, Toshiro; SUGIMOTO, Noboru

    2015-01-01

    At worksites, various automatic production machines are in use to release workers from muscular labor or labor in the detrimental environment. On the other hand, a large number of industrial accidents have been caused by automatic production machines. In view of this, this paper considers the operation of automatic production machines from the viewpoint of accident prevention, and points out two types of machine operation − operation for which quick performance is required (operation that is not permitted to be delayed) − and operation for which composed performance is required (operation that is not permitted to be performed in haste). These operations are distinguished by operation buttons of suitable colors and shapes. This paper shows that these characteristics are evaluated as “asymmetric on the time-axis”. Here, in order for workers to accept the risk of automatic production machines, it is preconditioned in general that harm should be sufficiently small or avoidance of harm is easy. In this connection, this paper shows the possibility of facilitating the acceptance of the risk of automatic production machines by enhancing the asymmetric on the time-axis. PMID:25739898