Sample records for elekriki haste shekafande

  1. Spatial and Temporal Analysis of Bias HAST System Temperature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pfeifer, Kent B.; Furrer, III, Clint T; Sandoval, Paul Anthony

    2017-03-01

    High-reliability components for high-consequence systems require detailed testing of operation after having undergone highly accelerated stress testing (HAST) under unusual conditions of high-temperature and humidity. This paper describes the design and operation of a system called "Wormwood" that is a highly multiplexed temperature measurement system that is designed to operate under HAST conditions to allow measurement of the temperature as a function of time and position in a HAST chamber. HAST chambers have single-point temperature measurements that can be traceable to NIST standards. The objective of these "Wormwood" measurements is to verify the uniformity and stability of the remaining volumemore » of the HAST chamber with respect to the single traceable standard.« less

  2. 77 FR 17327 - Amendment of Class E Airspace; Hastings, NE

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-26

    ...) Standard Instrument Approach Procedures at Hastings Municipal Airport. The FAA is taking this action to enhance the safety and management of Instrument Flight Rule (IFR) operations at the airport. DATES... accommodate new RNAV standard instrument approach procedures at Hastings Municipal Airport, Hastings, NE. This...

  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. Two Responses to Hastings on Labeling.

    ERIC Educational Resources Information Center

    Somogyi, Katherine M. M.; And Others

    1995-01-01

    Two comments respond to an R. P. Hastings article on labeling of individuals with mental retardation. The first comment notes that diagnoses should not be used as labels but as identifications of disorders a person has. The second comment calls for people to come forth with synonyms for "mental retardation" that will not immediately be stigmatic.…

  5. Agreement between T2 and haste sequences in the evaluation of thoracolumbar intervertebral disc disease in dogs.

    PubMed

    Mankin, Joseph M; Hecht, Silke; Thomas, William B

    2012-01-01

    The purpose of this study was to compare half-Fourier-acquisition single-shot turbo spin-echo (HASTE) and T2-weighted (T2-W) sequences in dogs with thoracolumbar disc extrusion. MRI studies in 60 dogs (767 individual intervertebral disc spaces) were evaluated. Agreement between T2-W and HASTE sequences was assessed for two criteria: presence of an extradural lesion and treatment recommendation. There was moderate agreement between T2-W and HASTE sequences as to presence of an extradural lesion (kappa = 0.575). HASTE was in agreement in 96.1% of the sites where no extradural lesion was identified on T2-W images, but only in 58.1% of the sites where extradural lesions were identified on T2-W images. There was also moderate agreement between T2-W and HASTE sequences as to treatment recommendations (kappa = 0.476). HASTE was in agreement in 98.4% of the sites where a lesion was considered nonsurgical on T2 but only 82.1% of sites a lesion was considered surgical on T2. In 1.0% of sites considered not surgical and in 9.8% of sites considered equivocal based on T2-W images, a surgical lesion was identified on HASTE. Acquisition of a HASTE sequence in addition to conventional sequences may be beneficial in determining the severity of spinal cord compression in some cases when evaluating the canine spine.

  6. Clinical application of Half Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) imaging accelerated by simultaneous multi-slice acquisition.

    PubMed

    Schulz, Jenni; P Marques, José; Ter Telgte, Annemieke; van Dorst, Anouk; de Leeuw, Frank-Erik; Meijer, Frederick J A; Norris, David G

    2018-01-01

    As a single-shot sequence with a long train of refocusing pulses, Half-Fourier Acquisition Single-Shot Turbo-Spin-Echo (HASTE) suffers from high power deposition limiting use at high resolutions and high field strengths, particularly if combined with acceleration techniques such as simultaneous multi-slice (SMS) imaging. Using a combination of multiband (MB)-excitation and PINS-refocusing pulses will effectively accelerate the acquisition time while staying within the SAR limitations. In particular, uncooperative and young patients will profit from the speed of the MB-PINS HASTE sequence, as clinical diagnosis can be possible without sedation. Materials and MethodsMB-excitation and PINS-refocusing pulses were incorporated into a HASTE-sequence with blipped CAIPIRINHA and TRAPS including an internal FLASH reference scan for online reconstruction. Whole brain MB-PINS HASTE data were acquired on a Siemens 3T-Prisma system from 10 individuals and compared to a clinical HASTE protocol. ResultsThe proposed MB-PINS HASTE protocol accelerates the acquisition by about a factor 2 compared to the clinical HASTE. The diagnostic image quality proved to be comparable for both sequences for the evaluation of the overall aspect of the brain, the detection of white matter changes and areas of tissue loss, and for the evaluation of the CSF spaces although artifacts were more frequently encountered with MB-PINS HASTE. ConclusionsMB-PINS HASTE enables acquisition of slice accelerated highly T2-weighted images and provides good diagnostic image quality while reducing acquisition time. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    DTIC Science & Technology

    1974-08-01

    consists of a padded cradle assembly and a tubular steel stand with lockable swivel casters on the front wheels . c Tne recovery module lifting handle is...eds no modification of the ordnance fired at it in order to function. With the HAST system a target will be provided to evaluate the most advanced...Components were tested under environmental extremes. With the completion of the preflight readiness tests and with modification incorporated during the

  8. 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…

  9. 76 FR 72867 - Proposed Amendment of Class E Airspace; Hastings, NE

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-28

    ... accommodate new Standard Instrument Approach Procedures (SIAP) at Hastings Municipal Airport. The FAA is taking this action to enhance the safety and management of Instrument Flight Rules (IFR) operations for... comments on this proposal to the U.S. Department of Transportation, Docket Operations, 1200 New Jersey...

  10. 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…

  11. A Bootstrap Metropolis-Hastings Algorithm for Bayesian Analysis of Big Data.

    PubMed

    Liang, Faming; Kim, Jinsu; Song, Qifan

    2016-01-01

    Markov chain Monte Carlo (MCMC) methods have proven to be a very powerful tool for analyzing data of complex structures. However, their computer-intensive nature, which typically require a large number of iterations and a complete scan of the full dataset for each iteration, precludes their use for big data analysis. In this paper, we propose the so-called bootstrap Metropolis-Hastings (BMH) algorithm, which provides a general framework for how to tame powerful MCMC methods to be used for big data analysis; that is to replace the full data log-likelihood by a Monte Carlo average of the log-likelihoods that are calculated in parallel from multiple bootstrap samples. The BMH algorithm possesses an embarrassingly parallel structure and avoids repeated scans of the full dataset in iterations, and is thus feasible for big data problems. Compared to the popular divide-and-combine method, BMH can be generally more efficient as it can asymptotically integrate the whole data information into a single simulation run. The BMH algorithm is very flexible. Like the Metropolis-Hastings algorithm, it can serve as a basic building block for developing advanced MCMC algorithms that are feasible for big data problems. This is illustrated in the paper by the tempering BMH algorithm, which can be viewed as a combination of parallel tempering and the BMH algorithm. BMH can also be used for model selection and optimization by combining with reversible jump MCMC and simulated annealing, respectively.

  12. A Bootstrap Metropolis–Hastings Algorithm for Bayesian Analysis of Big Data

    PubMed Central

    Kim, Jinsu; Song, Qifan

    2016-01-01

    Markov chain Monte Carlo (MCMC) methods have proven to be a very powerful tool for analyzing data of complex structures. However, their computer-intensive nature, which typically require a large number of iterations and a complete scan of the full dataset for each iteration, precludes their use for big data analysis. In this paper, we propose the so-called bootstrap Metropolis-Hastings (BMH) algorithm, which provides a general framework for how to tame powerful MCMC methods to be used for big data analysis; that is to replace the full data log-likelihood by a Monte Carlo average of the log-likelihoods that are calculated in parallel from multiple bootstrap samples. The BMH algorithm possesses an embarrassingly parallel structure and avoids repeated scans of the full dataset in iterations, and is thus feasible for big data problems. Compared to the popular divide-and-combine method, BMH can be generally more efficient as it can asymptotically integrate the whole data information into a single simulation run. The BMH algorithm is very flexible. Like the Metropolis-Hastings algorithm, it can serve as a basic building block for developing advanced MCMC algorithms that are feasible for big data problems. This is illustrated in the paper by the tempering BMH algorithm, which can be viewed as a combination of parallel tempering and the BMH algorithm. BMH can also be used for model selection and optimization by combining with reversible jump MCMC and simulated annealing, respectively. PMID:29033469

  13. 75 FR 45011 - MainStreet Savings Bank, FSB, Hastings, MI; Notice of Appointment of Receiver

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-30

    ... DEPARTMENT OF THE TREASURY Office of Thrift Supervision MainStreet Savings Bank, FSB, Hastings, MI... section 5(d)(2) of the Home Owners' Loan Act, the Office of Thrift Supervision has duly appointed the..., (OTS No. 00966) on July 16, 2010. Dated: July 23, 2010. By the Office of Thrift Supervision. Sandra E...

  14. 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.

  15. 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.

  16. 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.

  17. 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…

  18. Magnetic resonance cholangiopancreatography: value of using the half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence.

    PubMed

    Ho, J T; Yap, C K

    1999-05-01

    The purpose of this study was to evaluate the accuracy of magnetic resonance cholangiopancreatography (MRCP) for visualisation and diagnosis of pancreatico-biliary diseases. Our results of 35 case studies, correlating with results from endoscopic, percutaneous cholangiopancreatography or laparotomy, showed that MRCP performed using the half-Fourier acquisition single-shot turbo spin echo (HASTE) sequences was fast and accurate for depiction of the biliary and pancreatic system, with a diagnostic value comparable to that of direct cholangiography. The presence of biliary obstruction was accurately diagnosed in all but one patient. In hilar strictures, MR cholangiogram was able to depict the intrahepatic biliary tree proximal to the level of obstruction which was not readily displayed by endoscopic retrograde cholangiopancreatography (ERCP) (Figs. 1 & 2). This overview of the entire biliary system was found to be advantageous for preprocedural planning. However, the accuracy for stone detection was limited by the presence of aerobilia from previous sphincterotomy or biliary-enteric anastomosis. Ductal stones less than 3 mm in size within a non-dilated system may be missed due to inadequate spatial resolution. This occurred in a patient with pancreatic duct stones. It is hoped that the accuracy of HASTE magnetic resonance cholangiopancreatography in evaluation of pancreatico-biliary disease would obviate the need for diagnostic invasive cholangiography in selected patients.

  19. 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.

  20. The value of non-echo planar HASTE diffusion-weighted MR imaging in the detection, localisation and prediction of extent of postoperative cholesteatoma.

    PubMed

    Khemani, S; Lingam, R K; Kalan, A; Singh, A

    2011-08-01

    To evaluate the diagnostic performance of half-Fourier-acquisition single-shot turbo-spin-echo (HASTE) diffusion-weighted magnetic resonance imaging in the detection, localisation and prediction of extent of cholesteatoma following canal wall up mastoid surgery. Prospective blinded observational study. University affiliated teaching hospital. Forty-eight patients undergoing second-look surgery after previous canal wall up mastoid surgery for primary acquired cholesteatoma. All patients underwent non-echo planar HASTE diffusion-weighted imaging prior to being offered 'second-look' surgery. Radiological findings were correlated with second-look intra-operative findings in 38 cases with regard to presence, location and maximum dimensions of cholesteatoma. Half-Fourier-acquisition single-shot turbo-spin-echo diffusion-weighted imaging accurately predicted the presence of cholesteatoma in 23 of 28 cases, and it correctly excluded in nine of 10 cases. Five false negatives were caused by keratin pearls of <2 mm and in one case 5 mm. Overall sensitivity and specificity for detection of cholesteatoma were 82% (95% confidence interval [CI] 62-94%) and 90% (CI 55-100%), respectively. Positive predictive value and negative predictive value were 96% (CI 79-100%) and 64% (CI 35-87%), respectively. Overall accuracy for detection of cholesteatoma was 84% (CI 69-94%). Half-Fourier-acquisition single-shot turbo-spin-echo diffusion-weighted imaging has good performance in localising cholesteatoma to a number of anatomical sub-sites within the middle ear and mastoid (sensitivity ranging from 75% to 88% and specificity ranging from 94% to 100%). There was no statistically significant difference in the size of cholesteatoma detected radiologically and that found during surgery (paired t-test, P = 0.16). However, analysis of size agreement suggests possible radiological underestimation of size when using HASTE diffusion-weighted imaging (mean difference -0.6 mm, CI -5.3 to 4.6 mm). Half

  1. 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.

  2. 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.

  3. 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

  4. Finite Adaptation and Multistep Moves in the Metropolis-Hastings Algorithm for Variable Selection in Genome-Wide Association Analysis

    PubMed Central

    Peltola, Tomi; Marttinen, Pekka; Vehtari, Aki

    2012-01-01

    High-dimensional datasets with large amounts of redundant information are nowadays available for hypothesis-free exploration of scientific questions. A particular case is genome-wide association analysis, where variations in the genome are searched for effects on disease or other traits. Bayesian variable selection has been demonstrated as a possible analysis approach, which can account for the multifactorial nature of the genetic effects in a linear regression model. Yet, the computation presents a challenge and application to large-scale data is not routine. Here, we study aspects of the computation using the Metropolis-Hastings algorithm for the variable selection: finite adaptation of the proposal distributions, multistep moves for changing the inclusion state of multiple variables in a single proposal and multistep move size adaptation. We also experiment with a delayed rejection step for the multistep moves. Results on simulated and real data show increase in the sampling efficiency. We also demonstrate that with application specific proposals, the approach can overcome a specific mixing problem in real data with 3822 individuals and 1,051,811 single nucleotide polymorphisms and uncover a variant pair with synergistic effect on the studied trait. Moreover, we illustrate multimodality in the real dataset related to a restrictive prior distribution on the genetic effect sizes and advocate a more flexible alternative. PMID:23166669

  5. 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.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bogdanoff, Walter A.; Campos, Jocelyn; Perez, Edmundo I.

    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 bindmore » 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.« less

  7. Hastings Center

    MedlinePlus

    ... and Families Aging, Chronic Conditions, and End of Life Health and Health Care Science and the Self Humans and Nature Publications & Resources ... and Families Aging, Chronic Conditions, and End of Life Health and Health Care Science and the Self Humans and Nature Public Events ...

  8. 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

  9. COPD and air travel: does hypoxia-altitude simulation testing predict in-flight respiratory symptoms?

    PubMed

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

    2013-11-01

    The reduced pressure in an aircraft cabin may cause significant hypoxaemia and respiratory symptoms in patients with chronic obstructive pulmonary disease (COPD). The current study evaluated whether there is a relationship between hypoxaemia obtained during hypoxia-altitude simulation testing (HAST), simulating an altitude of 2438 m, and the reporting of respiratory symptoms during air travel. 82 patients with moderate to very severe COPD answered an air travel questionnaire. Arterial oxygen tensions during HAST (PaO2HAST) in subjects with and without in-flight respiratory symptoms were compared. The same questionnaire was answered within 1 year after the HAST. Mean ± sd PaO2HAST was 6.3 ± 0.6 kPa and 62 (76%) of the patients had PaO2HAST <6.6 kPa. 38 (46%) patients had experienced respiratory symptoms during air travel. There was no difference in PaO2HAST in those with and those without in-flight respiratory symptoms (6.3 ± 0.7 kPa versus 6.3 ± 0.6 kPa, respectively; p=0.926). 54 (66%) patients travelled by air after the HAST, and patients equipped with supplemental oxygen (n = 23, 43%) reported less respiratory symptoms when flying with than those without such treatment (four (17%) versus 11 (48%) patients; p=0.039). In conclusion, no difference in PaO2HAST was found between COPD patients with and without respiratory symptoms during air travel.

  10. Novel and classical human astroviruses in stool and cerebrospinal fluid: comprehensive screening in a tertiary care hospital, Switzerland.

    PubMed

    Cordey, Samuel; Vu, Diem-Lan; Zanella, Marie-Celine; Turin, Lara; Mamin, Aline; Kaiser, Laurent

    2017-09-20

    Classical human astroviruses (HAstV) are the third most common cause of non-bacterial acute gastroenteritis. Due to the lack of routine molecular assays, novel HAstV are underdiagnosed and the magnitude of their contribution to clinical disease remains unknown. To better understand their prevalence and the susceptible patient profile, we conducted a comprehensive screening of novel and classical HAstV in stool and cerebrospinal fluid (CSF) samples collected for clinical care in a tertiary care hospital using a specially designed rRT-PCR panel for the detection of novel (MLB1-3 and VA1-4) and classical HAstV. Of the 654 stool samples, 20 were positive for HAstV, and the novel (n=10; 3 MLB1, 4 MLB2; 3 VA2) and classical (n=10) serotypes were equally prevalent. None of the 105 CSF samples were positive. Investigating the patient profile, we found a higher prevalence (P=0.0002) of both novel and classical HAstV in pediatric stool samples (3.4% and 3%, respectively) compared with adult stool samples (0.5% and 0.7%, respectively). Furthermore, all novel and classical HAstV-positive pediatric subjects were ≤four years old, demonstrating similar susceptible populations. Forty-five percent of positive patients were immunocompromised (novel: 40%, classical: 50%). A comparison of novel and classical HAstV-positive cases showed a lower viral load for novel HAstV (P=0.0007) with significantly more upper respiratory symptoms (70% of subjects; P=0.02); this observation may suggest a unique pathogenic pathway. This study confirms the clinical and epidemiological relevance of novel HAstV and identifies a target population in which routine screening may yield clinically valuable information.

  11. 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.

  12. 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

  13. Structural Basis for Escape of Human Astrovirus from Antibody Neutralization: Broad Implications for Rational Vaccine Design

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bogdanoff, Walter A.; Perez, Edmundo I.; López, Tomás

    ABSTRACT Human astroviruses are recognized as a leading cause of viral diarrhea worldwide in children, immunocompromised patients, and the elderly. There are currently no vaccines available to prevent astrovirus infection; however, antibodies developed by healthy individuals during previous infection correlate with protection from reinfection, suggesting that an effective vaccine could be developed. In this study, we investigated the molecular mechanism by which several strains of human astrovirus serotype 2 (HAstV-2) are resistant to the potent HAstV-2-neutralizing monoclonal antibody PL-2 (MAb PL-2). Sequencing of the HAstV-2 capsid genes reveals mutations in the PL-2 epitope within the capsid's spike domain. To understandmore » the molecular basis for resistance from MAb PL-2 neutralization, we determined the 1.35-Å-resolution crystal structure of the capsid spike from one of these HAstV-2 strains. Our structure reveals a dramatic conformational change in a loop within the PL-2 epitope due to a serine-to-proline mutation, locking the loop in a conformation that sterically blocks binding and neutralization by MAb PL-2. We show that mutation to serine permits loop flexibility and recovers MAb PL-2 binding. Importantly, we find that HAstV-2 capsid spike containing a serine in this loop is immunogenic and elicits antibodies that neutralize all HAstV-2 strains. Taken together, our results have broad implications for rational selection of vaccine strains that do not contain prolines in antigenic loops, so as to elicit antibodies against diverse loop conformations. IMPORTANCEHuman astroviruses (HAstVs) infect nearly every person in the world during childhood and cause diarrhea, vomiting, and fever. In this study, we investigated how several strains of HAstV are resistant to a virus-neutralizing monoclonal antibody. We determined the crystal structure of the capsid protein spike domain from one of these HAstV strains and found that a single amino acid mutation

  14. A Center of Excellence in the Mathematical Sciences - at Cornell University

    DTIC Science & Technology

    1992-03-01

    of my recent efforts go in two directions. 1. Cellular Automata. The Greenberg Hastings model is a simple system that models the behavior of an... Greenberg -Hastings Model. We also obtained results concerning the crucial value for a threshold voter model. This resulted in the papers "Some Rigorous...Results for the Greenberg - Hastings Model" and "Fixation Results for Threshold Voter Systems." Together with Scot Adams, I wrote "An Application of the

  15. Clinical surveillance for human astrovirus in Monastir region, Tunisia.

    PubMed

    Monastiri, Abir; Aouni, Mahjoub; Guix, Susana; Mechri, Badereddine; Lopez-Roig, Marc; Abid, Nabil Ben Salem; Gueddiche, Neji; Hamami, Sabeur; Boughzala, Lamjed; Serra-Cobo, Jordi

    2016-01-21

    Astroviruses (AstVs) are enteric viruses that can cause gastroenteritis in children. This study is part of monitoring the circulation of astroviruses in children hospitalized and/or outpatients for acute gastroenteritis at the primary care center of Ouerdanine or at the Pediatric Department of the University Hospital Fattouma-Bourguiba (Monastir, Tunisia). The aims of our study were to know the prevalence of human astrovirus in clinical samples of children, characterize the strains and evaluate the infectivity of isolated strains on cell culture. Fifty stool samples were collected from children under five years old in the region of Monastir (Tunisia) from October 2010 to June 2011. All specimens were subjected to RT-PCR amplification followed by sequencing and phylogenetic analysis. The study shows a low prevalence of astrovirus (4 %) in children. The two positive samples obtained were HAstV type 3. Samples that were RT-PCR positive were cultured in CaCO-2 cells and the presence of infectious viral particles was confirmed. The phylogenetic analysis shows that the different HAstV-3 strains isolated in Tunisia are grouped into two clusters. The first cluster includes strains obtained in 2004, which belong to lineage HAstV-3a, while strains isolated in 2010 belong to lineage HAstV-3c. This study is part of monitoring the circulation of astroviruses in children younger than five years old from Monastir region, Tunisia. The results show low prevalence (4 %). All genotyped samples belonged to lineage HAstV-3c, which could be presently emerging. Two different lineages have been isolated in Tunisia: HAstV-3a in 2004 and HAstV-3c in 2010.

  16. Crystal Structure of the Human Astrovirus Capsid Protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Toh, Yukimatsu; Harper, Justin; Dryden, Kelly A.

    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 predominantmore » protein species with molecular masses of ~34, 27/29, and 25/26 kDa, respectively. We have now solved the crystal structure of VP90 71–415(amino acids [aa] 71 to 415 of VP90) of human astrovirus serotype 8 at a 2.15-Å resolution. VP90 71–415encompasses the conserved N-terminal domain of VP90 but lacks the hypervariable domain, which forms the capsid surface spikes. The structure of VP90 71–415is 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 VP90 71–415structure 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. IMPORTANCEHuman astrovirus (HAstV) is a leading cause of viral diarrhea in infants and young children worldwide. As a nonenveloped virus, HAst

  17. 76 FR 35866 - Sunshine Act Meeting Notice

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... SUPPLEMENTARY INFORMATION section of this notice. FOR FURTHER INFORMATION CONTACT: Nelson Hastings, NIST Voting... issues. The full meeting agenda will be posted in advance at http://vote.nist.gov . All sessions of this... disability accommodation, such as the need for Sign Language Interpretation, please contact Nelson Hastings...

  18. Negative Emotional Reactions to Challenging Behaviour and Staff Burnout: Two Replication Studies

    ERIC Educational Resources Information Center

    Rose, David; Horne, Sharon; Rose, John L.; Hastings, Richard P.

    2004-01-01

    Background: Hastings, R. P. ["American Journal on Mental Retardation" (2002) Vol. 107, pp. 455-467] hypothesized that staff negative emotional reactions to challenging behaviour might accumulate over time to affect staff well-being. Only one previous study (Mitchell, G.& Hastings, R. P. ["American Journal on Mental…

  19. 76 FR 21711 - Notice of Extension of Public Comment Period for the Draft Supplemental Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-18

    ..., and local agencies, as well as interested individuals, are invited and encouraged to review and... distributed to the following libraries and publicly accessible facilities for public review: 1. San Francisco..., 1360 Holloway Avenue, San Francisco, CA 94132. 3. Hastings Law Library, UC Hastings College of the Law...

  20. 75 FR 77858 - Sunshine Act Notice

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... this notice. FOR FURTHER INFORMATION CONTACT: Nelson Hastings, NIST Voting Program, Information... posted in advance at http://vote.nist.gov . All sessions of this meeting will be open to the public. A... for Sign Language Interpretation, please contact Nelson Hastings by c.o.b. Thursday, January 6, 2011...

  1. 77 FR 40345 - Notice of the Availability of Record of Decision for the Final Supplemental Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-09

    ... and Final SEIS are also available for viewing at the: 1. San Francisco Main Library, 100 Larkin Street, San Francisco, CA 94102; 2. San Francisco State University Library, 1360 Holloway Avenue, San Francisco, CA 94132; 3. Hastings Law Library, UC Hastings College of the Law, 200 McAllister Street, 4th...

  2. Pre-flight evaluation of adult patients with cystic fibrosis: a cross-sectional study.

    PubMed

    Edvardsen, Elisabeth; Akerø, Aina; Skjønsberg, Ole Henning; Skrede, Bjørn

    2017-02-06

    Air travel may imply a health hazard for patients with cystic fibrosis (CF) due to hypobaric environment in the aircraft cabin. The objective was to identify pre-flight variables, which might predict severe hypoxaemia in adult CF patients during air travel. Thirty adult CF-patients underwent pre-flight evaluation with spirometry, arterial oxygen tension (PaO 2 ), pulse oximetry (SpO 2 ) and cardiopulmonary exercise testing (CPET) at sea level (SL). The results were related to the PaO 2 obtained during a hypoxia-altitude simulation test (HAST) in which a cabin altitude of 2438 m (8000 ft) was simulated by breathing 15.1% oxygen. Four patients fulfilled the criteria for supplemental oxygen during air travel (PaO 2 HAST  < 6.6 kPa). While walking slowly during HAST, another eleven patients dropped below PaO 2 HAST 6.6 kPa. Variables obtained during CPET (PaO 2 CPET , SpO 2 CPET , minute ventilation/carbon dioxide output, maximal oxygen uptake) showed the strongest correlation to PaO 2 HAST . Exercise testing might be of value for predicting in-flight hypoxaemia and thus the need for supplemental oxygen during air travel in CF patients. Trial registration The study is retrospectively listed in the ClinicalTrials.gov Protocol Registration System: NCT01569880 (date; 30/3/2012).

  3. 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…

  4. 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. © 2015 Wiley Periodicals, Inc.

  5. 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...

  6. MRI of normal and abnormal duodenum using Half-Fourier Single-Shot RARE and gadolinium-enhanced spoiled gradient echo sequences.

    PubMed

    Marcos, H B; Semelka, R C; Noone, T C; Woosley, J T; Lee, J K

    1999-07-01

    The objective of this research was two-fold: First, to describe the normal and abnormal MR appearances of the duodenum using combined Half-Fourier Acquisition Single Shot RARE (HASTE) and gadolinium-enhanced standard and fat suppressed spoiled gradient echo (SGE) sequences. The second objective was to assess the ability of these combined sequences to detect and characterize duodenal diseases. MR examinations were performed on fifty consecutive patients with no clinical history of duodenal diseases, who were 1) imaged with HASTE and gadolinium-enhanced standard and fat suppressed SGE sequences and 2) referred to MR examination for reasons other than duodenal diseases, and were reviewed retrospectively to determine the normal MR appearances of the duodenum. A second population of patients with abnormal duodenum who were imaged with the same MR sequences were included in the second part of this study. This population was composed of 20 consecutive patients with subsequently proven duodenal abnormalities, including: malrotation (2), diverticula (4), intussusception (1), sprue (1), polyps (2), neurofibroma (1), lymphoma (1), Zollinger Ellison syndrome (1), metastatic disease (1), Crohn's disease (1), and wall thickening and duodenitis (5). Normal measurements of the duodenum are described. Abnormalities of wall thickness and duodenal masses required combined HASTE and gadolinium-enhanced SGE images to evaluate well. Abnormalities of the bowel lumen (e.g., diverticula and intussusception), and developmental variants (e.g., malrotation), were sufficiently visualized on HASTE images alone. Bowel inflammation was best shown on gadolinium-enhanced fat suppressed SGE images. HASTE and gadolinium-enhanced fat suppressed SGE sequences are complementary techniques for the demonstration of normal and abnormal duodenum. The combined use of both sequences allows evaluation of different aspects of bowel diseases; abnormalities of position, lumen, and contents are well shown on HASTE

  7. The psychology of autonomy.

    PubMed

    2016-05-01

    In May 2016, right around the time that this issue of the Hastings Center Report should be published, The Hastings Center is holding a conference in New York City titled "Bioethics Meets Moral Psychology." The goal of the conference is to consider the lessons that bioethicists should learn from the raft of literature now accumulating on how the mental processes of perception, emotion, and thinking affect things that bioethicists care about, from the education of health care professionals to the conflicts that arise in clinical care, the "culture wars" over bioethical policy issues, the status of different cultures' value systems, and the very understanding of the values that are foundational in moral thinking. The articles in this issue simply provide more evidence that bioethics is meeting moral psychology. © 2016 The Hastings Center.

  8. Alternative cell lines to improve the rescue of infectious human astrovirus from a cDNA clone.

    PubMed

    Velázquez-Moctezuma, Rodrigo; Baños-Lara, Ma del Rocío; Acevedo, Yunuén; Méndez, Ernesto

    2012-02-01

    A reverse genetics system for human astrovirus (HAstV) was established previously; however, it has not been exploited mainly because cells used for virus packaging are not permissive, requiring several rounds of replication to obtain acceptable infectious virus. In this work, in the search for alternative permissive cell lines to be used as packaging cells, Hek-293 and Huh7.5.1 were tested. Given that HAstV infection in Hek-293 showed differences with that in Caco-2, the gold standard for HAstV growth but scarcely transfectable, and it was more similar to that observed in the hepatoma Huh7.5.1 cell line, these last cells were further used to transfect viral RNA. Virus titers near to 10(8) infectious particles per ml (ffu/ml) were obtained at 16-20 h after transfection with RNA from infected cells. However, virus titers close to 10(6) ffu/ml were obtained by using in vitro transcribed RNA from a cDNA HAstV-1 clone. In contrast, virus recovery in BHK-21, reported previously as the packaging cells, from this RNA was of about 10(4) ffu/ml, two logarithms less than in Huh7.5.1. Apparently, the 5'-end modification of the viral RNA determined its specific infectivity, since virus recovery was abolished when the total RNA was treated with proteinase-K, probably by removing a protein-linked genome protein, but it increased when capping of the in vitro transcribed RNA was more efficient. Thus, an alternative and more efficient reverse genetics system for HAstV was established by using Huh7.5.1 cells. Copyright © 2011. Published by Elsevier B.V.

  9. 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.

  10. COPD and air travel: oxygen equipment and preflight titration of supplemental oxygen.

    PubMed

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

    2011-07-01

    Patients with COPD may need supplemental oxygen during air travel to avoid development of severe hypoxemia. The current study evaluated whether the hypoxia-altitude simulation test (HAST), in which patients breathe 15.1% oxygen simulating aircraft conditions, can be used to establish the optimal dose of supplemental oxygen. Also, the various types of oxygen-delivery equipment allowed for air travel were compared. In a randomized crossover trial, 16 patients with COPD were exposed to alveolar hypoxia: in a hypobaric chamber (HC) at 2,438 m (8,000 ft) and with a HAST. During both tests, supplemental oxygen was given by nasal cannula (NC) with (1) continuous flow, (2) an oxygen-conserving device, and (3) a portable oxygen concentrator (POC). PaO(2) kPa (mm Hg) while in the HC and during the HAST with supplemental oxygen at 2 L/min (pulse setting 2) on devices 1 to 3 was (1) 8.6 ± 1.0 (65 ± 8) vs 12.5 ± 2.4 (94 ± 18) (P < .001), (2) 8.6 ± 1.6 (64 ± 12) vs 9.7 ± 1.5 (73 ± 11) (P < .001), and (3) 7.7 ± 0.9 (58 ± 7) vs 8.2 ± 1.1 (62 ± 8) (P= .003), respectively. The HAST may be used to identify patients needing supplemental oxygen during air travel. However, oxygen titration using an NC during a HAST causes accumulation of oxygen within the facemask and underestimates the oxygen dose required. When comparing the various types of oxygen-delivery equipment in an HC at 2,438 m (8,000 ft), compressed gaseous oxygen with continuous flow or with an oxygen-conserving device resulted in the same PaO(2), whereas a POC showed significantly lower PaO(2) values. ClinicalTrials.gov; No.: Identifier: NCT01019538; URL: clinicaltrials.gov.

  11. [Construction and expression of six deletion mutants of human astrovirus C-terminal nsP1a/4 protein].

    PubMed

    Zhao, Wei; Niu, Ke; Zhao, Jian; Jin, Yi-ming; Sui, Ting-ting; Wang, Wen

    2013-09-01

    Human astrovirus (HAstV) is one of the leading causes of actue virual diarrhea in infants. HAstV-induced epithdlial cell apoptosis plays an important role in the pathogenesis of HAstV infection. Our previous study indicated that HAstV non-structural protein nsPla C-terminal protein nsPla/4 was the major apoptosis functional protein and probably contained the main apoptosis domains. In order to screen for astrovirus encoded apoptotic protien, nsPla/4 and six turncated proteins, which possessed nsPla/4 protein different function domain ,were cloned into green fluorescent protein (GFP) vector pEG-FP-N3. After 24-72 h transfection, the fusion protein expression in BHK21 cells, was analysis by fluorescence microscope and Western blot. The results indicated seven fusion proteins were observed successfully in BHK21 cell after transfected for 24 h. Western blot analysis showed that the level of fusion protein expressed in BHK21 cells was increased significantly at 72h compared to 48h in transfected cells. The successful expression of deletion mutants of nsPla/4 protein was an important foundation to gain further insights into the function of apoptosis domains of nsPla/4 protein and it would also provide research platform to further confirm the molecule pathogenic mechanism of human astrovirus.

  12. 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.

  13. Bioethics and Science.

    PubMed

    2018-03-01

    Bioethics comes in for furious criticism in Stephen Pinker's new book, Enlightenment Now. Pinker argues that scientists are making human lives better and better, and that lives would get still better even faster if bioethicists did not use ideas like informed consent, dignity, sacredness, and social justice to hobble the scientists. Daniel Callahan, a cofounder of The Hastings Center and arguably of bioethics, is perhaps the best living embodiment of a bioethicist who has written about medical progress, and the March-April 2018 issue of the Hastings Center Report turns to him for a review of Pinker's book. In his essay, Callahan describes bioethics as guiding science, addressing problems generated by scientific developments and attempting to head off possible problems, rather than as broadly opposing science. That description of bioethics serves as well as anything to convey the flavor of much of this issue of the Report. © 2018 The Hastings Center.

  14. MontePython 3: Parameter inference code for cosmology

    NASA Astrophysics Data System (ADS)

    Brinckmann, Thejs; Lesgourgues, Julien; Audren, Benjamin; Benabed, Karim; Prunet, Simon

    2018-05-01

    MontePython 3 provides numerous ways to explore parameter space using Monte Carlo Markov Chain (MCMC) sampling, including Metropolis-Hastings, Nested Sampling, Cosmo Hammer, and a Fisher sampling method. This improved version of the Monte Python (ascl:1307.002) parameter inference code for cosmology offers new ingredients that improve the performance of Metropolis-Hastings sampling, speeding up convergence and offering significant time improvement in difficult runs. Additional likelihoods and plotting options are available, as are post-processing algorithms such as Importance Sampling and Adding Derived Parameter.

  15. Error reduction, patient safety and institutional ethics committees.

    PubMed

    Meaney, Mark E

    2004-01-01

    Institutional ethics committees remain largely absent from the literature on error reduction and patient safety. In this paper, the author endeavors to fill the gap. As noted in the Hastings Center's recent report, "Promoting Patient Safety," the occurrence of medical error involves complex web of multiple factors. Human misstep is certainly one such factor, but not the only one. This paper builds on the Hastings Center's report in arguing that institutional ethics committees ought to play an integral role in the transformation of a "culture of blame" to a "culture of safety" in healthcare delivery.

  16. Blind haste: As light decreases, speeding increases.

    PubMed

    de Bellis, Emanuel; Schulte-Mecklenbeck, Michael; Brucks, Wernher; Herrmann, Andreas; Hertwig, Ralph

    2018-01-01

    Worldwide, more than one million people die on the roads each year. A third of these fatal accidents are attributed to speeding, with properties of the individual driver and the environment regarded as key contributing factors. We examine real-world speeding behavior and its interaction with illuminance, an environmental property defined as the luminous flux incident on a surface. Drawing on an analysis of 1.2 million vehicle movements, we show that reduced illuminance levels are associated with increased speeding. This relationship persists when we control for factors known to influence speeding (e.g., fluctuations in traffic volume) and consider proxies of illuminance (e.g., sight distance). Our findings add to a long-standing debate about how the quality of visual conditions affects drivers' speed perception and driving speed. Policy makers can intervene by educating drivers about the inverse illuminance‒speeding relationship and by testing how improved vehicle headlights and smart road lighting can attenuate speeding.

  17. 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...

  18. 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

  19. 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.

  20. Monte Carlo sampling in diffusive dynamical systems

    NASA Astrophysics Data System (ADS)

    Tapias, Diego; Sanders, David P.; Altmann, Eduardo G.

    2018-05-01

    We introduce a Monte Carlo algorithm to efficiently compute transport properties of chaotic dynamical systems. Our method exploits the importance sampling technique that favors trajectories in the tail of the distribution of displacements, where deviations from a diffusive process are most prominent. We search for initial conditions using a proposal that correlates states in the Markov chain constructed via a Metropolis-Hastings algorithm. We show that our method outperforms the direct sampling method and also Metropolis-Hastings methods with alternative proposals. We test our general method through numerical simulations in 1D (box-map) and 2D (Lorentz gas) systems.

  1. Business ethics in ethics committees?

    PubMed

    Boyle, P

    1990-01-01

    The "Ethics committees" column in this issue of the Hastings Center Report features an introduction by Cynthia B. Cohen and four brief commentaries on the roles hospital ethics committees may play in the making of institutional and public health care policy in the 1990s. The pros and cons of a broader, more public role for ethics committees in reconciling the business and patient care aspects of health care delivery are debated by Cohen in "Ethics committees as corporate and public policy advocates," and by Philip Boyle in this article. Boyle is an associate for ethical studies at The Hastings Center.

  2. What is the most suitable MR signal index for quantitative evaluation of placental function using Half-Fourier acquisition single-shot turbo spin-echo compared with T2-relaxation time?

    PubMed

    Kameyama, Kyoko Nakao; Kido, Aki; Himoto, Yuki; Moribata, Yusaku; Minamiguchi, Sachiko; Konishi, Ikuo; Togashi, Kaori

    2018-06-01

    Background Half-Fourier acquisition single-shot turbo spin-echo (HASTE) imaging is now widely used for placental and fetal imaging because of its rapidity and low sensitivity to fetal movement. If placental dysfunction is also predicted by quantitative value obtained from HASTE image, then it might be beneficial for evaluating placental wellbeing. Purpose To ascertain the most suitable magnetic resonance (MR) signal indexes reflecting placental function using HASTE imaging. Material and Methods This retrospective study included 37 consequent patients who had given informed consent to MR imaging (MRI) examinations. All had undergone MRI examinations between February 2014 and June 2015. First, the correlation between T2-relaxation time of normal placenta and gestational age (GA) was examined. Second, correlation between signal intensity ratios (SIRs) using HASTE imaging and placental T2-relaxation time were assessed. The SIRs were calculated using placental signal intensity (SI) relative to the SI of the amniotic fluid, fetal ocular globes, gastric fluid, bladder, maternal psoas major muscles, and abdominal subcutaneous adipose tissue. Results Among the 37 patients, the correlation between T2-relaxation time of the 25 normal placentas and GA showed a moderately strong correlation (Spearman rho = -0.447, P = 0.0250). The most significant correlation with placental T2-relaxation time was observed with the placental SIR relative to the maternal psoas major muscles (SIR pl./psoas muscle ) (Spearman rho = -0.531, P = 0.0007). Conclusion This study revealed that SIR pl./psoas muscle showed the best correlation to placental T2-relaxation time. Results show that SIR pl./psoas muscle might be optimal as a clinically available quantitative index of placental function.

  3. Bioethics as care work.

    PubMed

    Reynolds, Joel Michael

    2018-01-01

    German philosopher Martin Heidegger argued that humans are defined by care. The term he used, "Sorge," picks out a wide range of caring relations, including sorrow, worry, the making of arrangements, and even fending for another. Since coming to The Hastings Center, I've been struck by the genuine care definitive of its scholars' relationship to their work. Care about newborns, the elderly, and nonhuman animals. Care about doctors, nurses, and health care institutions. Care expressed in the panoply of ways biomedical knowledge and practices inform our havings, doings, and beings in the world. Perhaps in its better moments, bioethics just is care work. But care work is hard and messy. © 2018 The Hastings Center.

  4. 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…

  5. 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

  6. Comparison of gadolinium-EOB-DTPA-enhanced and diffusion-weighted liver MRI for detection of small hepatic metastases.

    PubMed

    Shimada, Kotaro; Isoda, Hiroyoshi; Hirokawa, Yuusuke; Arizono, Shigeki; Shibata, Toshiya; Togashi, Kaori

    2010-11-01

    To compare the accuracy of gadolinium ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI with that of diffusion-weighted MRI (DWI) in the detection of small hepatic metastases (2 cm or smaller). Forty-five patients underwent abdominal MRI at 3 T, including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), heavily T2WI (HASTE), DWI with a b-value of 500 s/mm(2) and contrast-enhanced MRI with Gd-EOB-DTPA. Two groups were assigned and compared: group A (T1WI, T2WI, HASTE and contrast-enhanced study with Gd-EOB-DTPA), and group B (T1WI, T2WI, HASTE and DWI). Two observers independently interpreted the images obtained in a random order. For all hepatic metastases, the diagnostic performance using each imaging set was evaluated by receiver-operating characteristic (ROC) curve analysis. A total of 51 hepatic metastases were confirmed. The area under the ROC curve (Az) of group A was larger than that of group B, and the difference in the mean Az values between the two image sets was statistically significant, whereas, there were three metastases that lay near thin vessels or among multiple cysts and were better visualised in group B than in group A. Gd-EOB-DTPA-enhanced MRI showed higher accuracy in the detection of small metastases than DWI.

  7. Probabilistic learning of nonlinear dynamical systems using sequential Monte Carlo

    NASA Astrophysics Data System (ADS)

    Schön, Thomas B.; Svensson, Andreas; Murray, Lawrence; Lindsten, Fredrik

    2018-05-01

    Probabilistic modeling provides the capability to represent and manipulate uncertainty in data, models, predictions and decisions. We are concerned with the problem of learning probabilistic models of dynamical systems from measured data. Specifically, we consider learning of probabilistic nonlinear state-space models. There is no closed-form solution available for this problem, implying that we are forced to use approximations. In this tutorial we will provide a self-contained introduction to one of the state-of-the-art methods-the particle Metropolis-Hastings algorithm-which has proven to offer a practical approximation. This is a Monte Carlo based method, where the particle filter is used to guide a Markov chain Monte Carlo method through the parameter space. One of the key merits of the particle Metropolis-Hastings algorithm is that it is guaranteed to converge to the "true solution" under mild assumptions, despite being based on a particle filter with only a finite number of particles. We will also provide a motivating numerical example illustrating the method using a modeling language tailored for sequential Monte Carlo methods. The intention of modeling languages of this kind is to open up the power of sophisticated Monte Carlo methods-including particle Metropolis-Hastings-to a large group of users without requiring them to know all the underlying mathematical details.

  8. 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

  9. 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

  10. Genetics Home Reference: Bohring-Opitz syndrome

    MedlinePlus

    ... Most cases of the condition result from new (de novo) mutations in the gene that occur during ... BW, Rodríguez-Santiago B, Gilissen C, Vissers LE, de Vries P, Janssen I, van Lier B, Hastings ...

  11. Feasibility Test of a Pulse Modulated Pressurization System for a High Altitude Supersonic Target Vehicle Propulsion System.

    DTIC Science & Technology

    1976-11-01

    pressure switch . The system was tested for stability of operation and accuracy of pressure control, using a High Altitude Supersonic Target (HAST...stable and accurate to approximately the deadband of the pressure switch used, 2 psi. (Author)

  12. Security : breaches at federal agencies and airports

    DOT National Transportation Integrated Search

    2000-01-01

    This is the statement of Robert H. Hast, Assistance Comptroller General for Investigations, Office of Special Investigations before the Subcommittee on Crime, House Committee on the Judiciary about potential security risks to the United States. The G...

  13. Preliminary Flight Rating Tests of the HAST Propulsion System

    DTIC Science & Technology

    1975-01-01

    each data channel once every 10 milliseconds. The accelerometer output, as well as certain other pressures for which high response data was required...4" 0 rl: TT h 2-, tt r4’ir 11T, Fri LO - 7 11 1 , , I- -If; 77 7 T ’r 71 H, ty! t2i if It 77 T , !- , "",pg T % T % 7z7 7 , 4’u H-PTi TF if", KV7

  14. 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.

  15. 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...

  16. 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.

  17. 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...

  18. 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....

  19. 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.

  20. 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…

  1. Maximum Likelihood Estimation of Nonlinear Structural Equation Models.

    ERIC Educational Resources Information Center

    Lee, Sik-Yum; Zhu, Hong-Tu

    2002-01-01

    Developed an EM type algorithm for maximum likelihood estimation of a general nonlinear structural equation model in which the E-step is completed by a Metropolis-Hastings algorithm. Illustrated the methodology with results from a simulation study and two real examples using data from previous studies. (SLD)

  2. 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.

  3. 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...

  4. 75 FR 39706 - Notice of Lodging of Consent Decree Under the Comprehensive Environmental Response, Compensation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-12

    ... DEPARTMENT OF JUSTICE Notice of Lodging of Consent Decree Under the Comprehensive Environmental Response, Compensation and Liability Act Notice is given that on July 1, 2010, a proposed Consent Decree in... against the City of Hastings under Sections 106 and 107(a) of the Comprehensive Environmental Response...

  5. Quantitative Nondestructive Evaluation

    DTIC Science & Technology

    1979-10-01

    reliability has been discussed by a number of researchers, including Pachman, et. al. [25,28], Hastings [29], Ehret [30], Kaplan and Reiman [31], and...123 REFERENCES (Continued) 31. Kaplan, M.P. and Reiman , J.A. "Use of Fracture Mechanics in Estimating Structural Life and Inspection Intervals

  6. A note-and a call-from the weeds.

    PubMed

    Latham, Stephen R

    2018-05-01

    For the past few years I've had the distinct privilege to edit the Hastings Center Report's Policy & Politics column. The column-as indicated by a little block of text at its end-was originally conceived as, and remains, a joint production of HCR and the American Society for Bioethics and Humanities. For me, as column editor, this means that I can accept contributions only from ASBH members. Luckily this presents me with an extremely large pool of talent from which to draw! I am very proud of the fact that a large majority of contributors to the column in the last several years had never written in HCR before I invited them to contribute. But naturally, I don't know everyone, and I can't keep track of everything. I'd love to get even more unsolicited offers of P&P contributions than I already enjoy. © 2018 The Hastings Center.

  7. 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

  8. 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.

  9. 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…

  10. 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…

  11. 76 FR 3092 - Endangered Species Permit No. 1578-01 and Permit No. 1595-04

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

    ... Species Permit No. 1578-01 and Permit No. 1595-04 AGENCY: National Marine Fisheries Service (NMFS... research permits (Permit Nos. 1578 and 1595- 03) to take shortnose sturgeon for purposes of scientific... State House Station, Augusta, ME, 04333 (Permit No. 1578); and Michael M. Hastings, University of Maine...

  12. 75 FR 58350 - Endangered Species; Permit No. 1578-01; and Permit No. 1595-04

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ... Species; Permit No. 1578-01; and Permit No. 1595-04 AGENCY: National Marine Fisheries Service (NMFS... modifications to permits (Permit Nos. 1578 and 1595-03) to take shortnose sturgeon for purposes of scientific... State House Station, Augusta, ME, 04333 (Permit No. 1578); and Michael M. Hastings, University of Maine...

  13. Acoustic Sensor Network Design for Position Estimation

    DTIC Science & Technology

    2009-05-01

    A., Pollock, S., Netter, B., and Low, B. S. 2005. Anisogamy, expenditure of reproductive effort, and the optimality of having two sexes. Operations...Research 53, 3, 560–567. Evans, M., Hastings, N., and Peacock , B. 2000. Statistical distributions. Ed. Wiley & Sons. New York. Feeney, L. and Nilsson, M

  14. 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…

  15. 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…

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weaver, Brian Phillip

    The purpose of this document is to describe the statistical modeling effort for gas concentrations in WIPP storage containers. The concentration (in ppm) of CO 2 in the headspace volume of standard waste box (SWB) 68685 is shown. A Bayesian approach and an adaptive Metropolis-Hastings algorithm were used.

  17. 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,…

  18. "(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.…

  19. 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…

  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. 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…

  2. 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…

  3. 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...

  4. "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…

  5. 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,…

  6. 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…

  7. Comparison of Different Magnetic Resonance Cholangiography Techniques in Living Liver Donors Including Gd-EOB-DTPA Enhanced T1-Weighted Sequences

    PubMed Central

    Kinner, Sonja; Steinweg, Verena; Maderwald, Stefan; Radtke, Arnold; Sotiropoulos, Georgios; Forsting, Michael; Schroeder, Tobias

    2014-01-01

    Objectives Preoperative evaluation of potential living liver donors (PLLDs) includes the assessment of the biliary anatomy to avoid postoperative complications. Aim of this study was to compare T2-weighted (T2w) and Gd-EOB-DTPA enhanced T1-weighted (T1w) magnetic resonance cholangiography (MRC) techniques in the evaluation of PLLDs. Materials and Methods 30 PLLDs underwent MRC on a 1.5 T Magnetom Avanto (Siemens, Erlangen, Germany) using (A) 2D T2w HASTE (Half Fourier Acquisition Single Shot Turbo Spin Echo) fat saturated (fs) in axial plane, (B) 2D T2w HASTE fs thick slices in coronal plane, (C) free breathing 3D T2w TSE (turbo spin echo) RESTORE (high-resolution navigator corrected) plus (D) maximum intensity projections (MIPs), (E) T2w SPACE (sampling perfection with application optimized contrasts using different flip angle evolutions) plus (F) MIPs and (G) T2w TSE BLADE as well as Gd-EOB-DTPA T1w images without (G) and with (H) inversion recovery. Contrast enhanced CT cholangiography served as reference imaging modality. Two independent reviewers evaluated the biliary tract anatomy on a 5-point scale subjectively and objectively. Data sets were compared using a Mann-Whitney-U-test. Kappa values were also calculated. Results Source images and maximum intensity projections of 3D T2w TSE sequences (RESTORE and SPACE) proved to be best for subjective and objective evaluation directly followed by 2D HASTE sequences. Interobserver variabilities were good to excellent (k = 0.622–0.804). Conclusions 3D T2w sequences are essential for preoperative biliary tract evaluation in potential living liver donors. Furthermore, our results underline the value of different MRCP sequence types for the evaluation of the biliary anatomy in PLLDs including Gd-EOB-DTPA enhanced T1w MRC. PMID:25426932

  8. Human enteric viruses in a wastewater treatment plant: evaluation of activated sludge combined with UV disinfection process reveals different removal performances for viruses with different features.

    PubMed

    Lizasoain, A; Tort, L F L; García, M; Gillman, L; Alberti, A; Leite, J P G; Miagostovich, M P; Pou, S A; Cagiao, A; Razsap, A; Huertas, J; Berois, M; Victoria, M; Colina, R

    2018-03-01

    This study assess the quality of wastewater through the detection and quantification of important viruses causing gastroenteritis at different stages of the wastewater treatment process in an activated-sludge wastewater treatment plant with ultraviolet disinfection. Ten sampling events were carried out in a campaign along a period of 18 months collecting wastewater samples from the influent, after the activated-sludge treatment, and after the final disinfection with UV radiation. Samples were concentrated through ultracentrifugation and analysed using retro-transcription, PCR and real time quantitative PCR protocols, for detection and quantification of Group A Rotavirus (RVA), Human Astrovirus (HAstV), Norovirus Genogroup II (NoV GII) and Human Adenovirus (HAdV). HAdV (100%), NoV GII (90%), RVA (70%) and HAstV (60%) were detected in influent samples with concentration from 1·4 (NoV GII) to 8·0 (RVA) log 10  gc l -1 . Activated-sludge treatment reached well quality effluents with low organic material concentration, although nonstatistical significant differences were registered among influent and postactivated sludge treatment samples, regarding the presence and concentration for most viruses. All post-UV samples were negative for NoV GII and HAstV, although RVA and HAdV were detected in 38% and 63% of those samples respectively, with concentration ranging from 2·2 to 5·5 and 3·1 to 3·4 log 10  gc l -1 . This study demonstrates that an activated-sludge wastewater treatment plant with UV disinfection reduces to levels below the detection limit those single-stranded RNA viruses as noroviruses and astroviruses and reach significant lower levels of rotaviruses and adenoviruses after the complete treatment process. © 2017 The Society for Applied Microbiology.

  9. 75 FR 69666 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Memorial Drive, Kansas City, Missouri 64198-0001: 1. Kenneth L. Morrison, Hastings, Nebraska; to acquire... Holding Company The notificants listed below have applied under the Change in Bank Control Act (12 U.S.C... paragraph 7 of the Act (12 U.S.C. 1817(j)(7)). The notices are available for immediate inspection at the...

  10. 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…

  11. 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…

  12. 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.

  13. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-12-08

    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: 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

  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. Authenticity, Best Interest, and Clinical Nudging.

    PubMed

    Holm, Søren

    2017-03-01

    In this issue of the Hastings Center Report, Moti Gorin, Steven Joffe, Neal Dickert, and Scott Halpern offer a comprehensive defense of the use of nudging techniques in the clinical context, with the aim of promoting the best interests of patients. Their argument is built on three important claims: Nudging is ubiquitous and inescapable in clinical choice situations, and there is no neutral way of informing patients about their treatment choices; many patients do not have authentic (preexisting) preferences concerning their treatment choices, and those that do can easily resist nudging; and, finally, since many people lack authentic preferences and those that do can still act on their preferences, nudging in the patients' best interest is justified. I agree with the authors that if these three claims stand up to scrutiny, then they will provide a justification for many types of clinical nudging. I am, however, skeptical as to whether the claims can be sustained, despite the valiant efforts of Gorin and colleagues. © 2017 The Hastings Center.

  16. Searching for efficient Markov chain Monte Carlo proposal kernels

    PubMed Central

    Yang, Ziheng; Rodríguez, Carlos E.

    2013-01-01

    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. PMID:24218600

  17. Earth, Wind, Flu, Flood and Fire: Early Evolution of U.S. National Policy for Natural Disaster Response

    DTIC Science & Technology

    2009-12-11

    Man-made disasters include engineering failures, transportation accidents, industrial accidents, or weapons of mass destruction. Historical...chemical, biological , radiological, nuclear, and high yield explosive incidents. Another exemption is Commander’s Emergency Authority, which authorizes...Pandemic.” In From Birth to Death and Bench to Clinic: The Hastings Center Bioethics Briefing Book for Journalists, Policymakers, and Campaigns. ed. Mary

  18. 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…

  19. 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

  20. 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

  1. 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…

  2. 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.

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

    DTIC Science & Technology

    1978-03-01

    plate 2. The line would continue down the road to L/D 2, turn vest and follow the property line of the Koch Refining Company , pass through the center of...existing poles in the lake would be removed and the lake crossed in a single span. 11A SECTION ONE PROJECT DESCRIPTION 1.052 Northern States Power Company ...to pay, a hypothetical day-use value is carefully estimated and applied to the annual project visitation projection to determine project benefits. A

  4. 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

  5. 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.…

  6. 77 FR 62498 - Advisory Council on Dependents' Education; Meeting Cancellation Notice and Open Meeting Notice

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-15

    ... the provisions of the Federal Advisory Committee Act of 1972 (5 U.S.C., Appendix, as amended), and the Government in the Sunshine Act of 1976 (5 U.S.C. 552b, as amended), and scheduled to occur on Tuesday...-Aleutian Standard Time (H-AST); Peachtree City, Georgia, from 8:00 a.m. to 12:00 p.m., Eastern Daylight...

  7. 77 FR 53187 - Advisory Council on Dependents' Education; Notice of Open Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ..., from 2 a.m. to 6 a.m., Hawaii-Aleutian Standard Time (H-AST); Peachtree City, Georgia, from 8 a.m. to..., Georgia. FOR FURTHER INFORMATION CONTACT: Mr. Joel K. Hansen at (571) 372-5812 or Joel.Hansen@hq.dodea.edu... before the Council. Public Accessibility to the Meeting: Pursuant to 5 U.S.C. 552b and 41 CFR 102-3.140...

  8. 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.

  9. Comparison of sampling techniques for Bayesian parameter estimation

    NASA Astrophysics Data System (ADS)

    Allison, Rupert; Dunkley, Joanna

    2014-02-01

    The posterior probability distribution for a set of model parameters encodes all that the data have to tell us in the context of a given model; it is the fundamental quantity for Bayesian parameter estimation. In order to infer the posterior probability distribution we have to decide how to explore parameter space. Here we compare three prescriptions for how parameter space is navigated, discussing their relative merits. We consider Metropolis-Hasting sampling, nested sampling and affine-invariant ensemble Markov chain Monte Carlo (MCMC) sampling. We focus on their performance on toy-model Gaussian likelihoods and on a real-world cosmological data set. We outline the sampling algorithms themselves and elaborate on performance diagnostics such as convergence time, scope for parallelization, dimensional scaling, requisite tunings and suitability for non-Gaussian distributions. We find that nested sampling delivers high-fidelity estimates for posterior statistics at low computational cost, and should be adopted in favour of Metropolis-Hastings in many cases. Affine-invariant MCMC is competitive when computing clusters can be utilized for massive parallelization. Affine-invariant MCMC and existing extensions to nested sampling naturally probe multimodal and curving distributions.

  10. EMPFASIS: A Publication of the National Electronics Manufacturing Center of Excellence

    DTIC Science & Technology

    2010-01-01

    for moisture, salt spray, and wind driven rain protection. • Conversion to ruggedized electrical and fluid connectors. • Additional circuitry, if...computer control technology, designed for safe lead free and eutectic rework applications. Available in two models, the RD-500 series features a three-stage...shock, Temperature Humidity Bias (THB) Testing, Highly Accelerated Stress Testing (HAST), salt fog, high temperature storage, or other environmental

  11. Transport of Blue Crab Larvae in the Northern Gulf of Mexico During the Deepwater Horizon Oil Spill

    DTIC Science & Technology

    2015-05-11

    et al . 2001, Hastings & Botsford 2006, Bode et al . 2008, Kininmonth et al . 2010b) and empirical studies (Meynecke et al . 2008...corresponding author: btjones@mit.edu Rooker et al . 2008, Hinrichsen et al . 2011) of marine populations. Population connectivity may be defined as...the successful exchange of individuals among spatially separated sub-populations that constitute a single metapopulation (Cowen et al . 2007). It

  12. Environmental Impact Research Program. Ecological Effects of Rubble Weir Jetty Construction at Murrells Inlet, South Carolina. Volume 1. Colonization and Community Development on New Jetties.

    DTIC Science & Technology

    1984-04-01

    was not ., defined but approximated 65 cm2. d. Fish Observations and Collections Qualitative observations on ichthyofauna were made during...that P. caudata occurred mainly among algae, seagrass , sponges and the like insubtidal waters. Corophiwu sp. showed significantly greater abundance on...abundance and diversity of ichthyofauna in areas where they are present (Hastings, 1972, 1978; Hurme, 1979). A large number of fishes were observed on or

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Haste Makes Waste: The Interplay Between Dissolution and Precipitation of Supersaturating Formulations.

    PubMed

    Sun, Dajun D; Lee, Ping I

    2015-11-01

    Contrary to the early philosophy of supersaturating formulation design for oral solid dosage forms, current evidence shows that an exceedingly high rate of supersaturation generation could result in a suboptimal in vitro dissolution profile and subsequently could reduce the in vivo oral bioavailability of amorphous solid dispersions. In this commentary, we outline recent research efforts on the specific effects of the rate and extent of supersaturation generation on the overall kinetic solubility profiles of supersaturating formulations. Additional insights into an appropriate definition of sink versus nonsink dissolution conditions and the solubility advantage of amorphous pharmaceuticals are also highlighted. The interplay between dissolution and precipitation kinetics should be carefully considered in designing a suitable supersaturating formulation to best improve the dissolution behavior and oral bioavailability of poorly water-soluble drugs.

  18. Child malnutrition and the Millennium Development Goals: much haste but less speed?

    PubMed

    Oruamabo, Raphael S

    2015-02-01

    The Millennium Development Goals (MDGs) provide a framework for measuring the progress of nations. Several of these goals relate to child malnutrition, which remains an important contributor to child morbidity and mortality, accounting for approximately 45% of child deaths globally. A high proportion of undernourished children still live in Africa and parts of Asia, and the uneven rate of reduction in the prevalence of various types of child malnutrition among different income groups worldwide is worrying. Attempts to reduce child malnutrition should therefore begin from the grassroots by improving primary healthcare services in developing countries with particular focus on basic requirements. Adequate nutrition should be provided from birth, through infancy, preschool and early childhood to adolescence. The overall strategy should be one of careful and meticulous planning involving all development sectors with an emphasis on a bottom-up approach within a stable and disciplined polity; the MDGs will be only be useful if they are seen not as narrow objectives with unidirectional interventions but as multifaceted and co-ordinated. The setting of deadlines, whether 2015 or 2035, should not be emphasised so as to avoid hasty decision making. The top priority should be the implementation of the essential social services of basic education, primary healthcare, nutrition, reproductive health care, water and sanitation in partnership with the developed economies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  19. Somali Piracy and Anti-Shipping Activity Messages: Lessons for a Successful Counterpiracy Strategy

    DTIC Science & Technology

    2014-06-01

    solving the differences found in each organization’s reporting. This suggestion seems valid and demonstrates an unbiased approach. 19 The studies...agrees the IMB data sets are not free from debate and criticism, yet claims the reports provide the only consistent and reliable set of figures to...different approach to using piracy incident reports. Hastings (2009) explores the political and economic landscapes of failed and weak states to determine

  20. 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

  1. 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

  2. JPRS Report, Soviet Union, Political Affairs, Volkogonov’s Political Portrait of Stalin

    DTIC Science & Technology

    1989-07-06

    dozen other characteristics . When Dzhugash- vili-Stalin became a mighty man, his guardians of state security would not engage in such trifling...actions characteristic of an ordinary executant but also of skillful compromise, maneuvering and selection of the main component in the wide spectrum...Summing up, as it were, Lenin collated the political and moral characteristics of the general secretary: "I think that Stalin’s haste and

  3. 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. © 2016 The Hastings Center.

  4. 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.

  5. The Bombing of Brittany: Solving the Wrong Problem

    DTIC Science & Technology

    2010-05-21

    Record (South Yorkshire : Pen & Sword Books Ltd , 2005), 7. 30 Hastings, 126; Dudley Saward, Bomber Harris: The Story of Sir Arthur Harris, Marshal of the...Frank Cass and Co Ltd , 1995), 14-15. 76 Clout, 167. 77 Davis. Excel spreadsheets of bombing data from 1940-1945. 78 Williamson, 48. 79 Clout, 167...Ken. RAF Bomber Command 1936-1968: An Opertional and Historical Record. South Yorkshire : Pen & Sword Books Ltd , 2005. Dodd, Lindsey and Andrew

  6. The Nicaraguan Resistance and U.S. Policy: Report on a May 1987 Conference Held in Santa Monica, California.

    DTIC Science & Technology

    1989-06-01

    questions. This volume reports the proceedings of that conference, which was convened et The RAND Corporation in May 1987. In retrospect, it was an especially ...where 30 percent of the population resides ( especially Zelaya, Matagalpa, Chon- tales, and Jinotega). The major obstacle in 1987 will be to translate...This haste to overturn the Sandinistas had its merits, especially if one considers the promises of a rapid victory that the Americans had made to the

  7. A Service in Transition: Forging an Integrated Institutional Identity for the United States Air Force

    DTIC Science & Technology

    2010-06-01

    Jr (Bomber) o Seventh Air Force, LTG Jeffrey A. Remington (Fighter) o Eleventh Air Force, LTG Dana T. Atkins (Fighter) o Thirteenth Air Force, LTG...Acculturation.‖ In Handbook of Socialization: Theory and Research, edited by Joan E. Grusec, and Paul D. Hastings, 543-560. New York, NY: Guilford...Philip. ―Determinism and Indeterminacy in the History of Technology.‖ In Does Technology Drive History?, edited by Merritt Roe Smith, and Leo Marx

  8. The Falklands War: Understanding the Power of Context in Shaping Argentine Strategic Decisions

    DTIC Science & Technology

    2007-09-01

    junta was beholden. A detailed analysis of the forces engaged, the geography of the battle space, and the conduct of operations reveals that the...parity with the British in many aspects and advantages in others. The geography of the battle space gave the Argentines a superior position relative to...9 Max Hastings and Simon Jenkins, The Battle for the Falklands, 1st American ed., (New York: Norton, 1983), 1. 10 Central Intelligence Agency

  9. Heroes for a Wicked World: Enders Game as a Case for Fiction in PME

    DTIC Science & Technology

    2015-06-10

    Sengers, “Narrative Intelligence,” 3. 84. Blair, D. and Meyer, T. “Tools for an Interactive Virtual Cinema .” Creating Personalities for Synthetic Actors...Conflict . . . in Space. Historian Max Hastings writes, “It was the Japanese people’s ill-fortune that it became feasible to bomb them just when American...2012). Blair, D. and Meyer, T. “Tools for an Interactive Virtual Cinema .” Creating Personalities for Synthetic Actors: Towards Autonomous Personality

  10. Subacute Effects of Inhaled Jet Fuel-A (JET A) on Airway and Immune Function in Rats

    DTIC Science & Technology

    2012-07-16

    the source of the oil used in its manufacture. This study used fuel provided by five of the major oil companies ( blend POSF-4658, Chevron, Shell Oil... using a Hastings (Model 40) monitor. The chamber system schematic is depicted in Figure 4. Figure 4. Schematic of exposure control system...were used due to concerns that the air control animals (Group 2) might be unintentionally exposed to background levels of Jet A. Group 2 was exposed

  11. 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

  12. Lung MRI at 1.5 and 3 Tesla: observer preference study and lesion contrast using five different pulse sequences.

    PubMed

    Fink, Christian; Puderbach, Michael; Biederer, Juergen; Fabel, Michael; Dietrich, Olaf; Kauczor, Hans-Ulrich; Reiser, Maximilian F; Schönberg, Stefan O

    2007-06-01

    To compare the image quality and lesion contrast of lung MRI using 5 different pulse sequences at 1.5 T and 3 T. Lung MRI was performed at 1.5 T and 3 T using 5 pulse sequences which have been previously proposed for lung MRI: 3D volumetric interpolated breath-hold examination (VIBE), true fast imaging with steady-state precession (TrueFISP), half-Fourier single-shot turbo spin-echo (HASTE), short tau inversion recovery (STIR), T2-weighted turbo spin-echo (TSE). In addition to 4 healthy volunteers, 5 porcine lungs were examined in a dedicated chest phantom. Lung pathology (nodules and infiltrates) was simulated in the phantom by intrapulmonary and intrabronchial injections of agarose. CT was performed in the phantom for correlation. Image quality of the sequences was ranked in a side-by-side comparison by 3 blinded radiologists regarding the delineation of pulmonary and mediastinal anatomy, conspicuity of pulmonary nodules and infiltrates, and presence of artifacts. The contrast of nodules and infiltrates (CNODULES and CINFILTRATES) defined by the ratio of the signal intensities of the lesion and adjacent normal lung parenchyma was determined. There were no relevant differences regarding the preference for the individual sequences between both field strengths. TSE was the preferred sequence for the visualization of the mediastinum at both field strengths. For the visualization of lung parenchyma the observers preferred TrueFISP in volunteers and TSE in the phantom studies. At both field strengths VIBE achieved the best rating for the depiction of nodules, whereas HASTE was rated best for the delineation of infiltrates. TrueFISP had the fewest artifacts in volunteers, whereas STIR showed the fewest artifacts in the phantom. For all but the TrueFISP sequence the lesion contrast increased from 1.5 T to 3 T. At both field strengths VIBE showed the highest CNODULES (6.6 and 7.1) and HASTE the highest CINFILTRATES (6.1 and 6.3). The imaging characteristics of different

  13. Sea Ice Movements from Synthetic Aperture Radar

    DTIC Science & Technology

    1981-12-01

    correlating these components. B-l8 These correlations are also plotted in figure l1. 5.3.3.2 AUlications of the space correlation. The spatial...aperture radar. To appear in J. of Geophys. Res. Hastings, A. D. Jr., 1971. Surface climate of the Arctic Basin. Report ETL- TR-71-5, Earth Sciences Division...Administration Grant NA50-AA-D-00015, which was funded in part by the Global Atmospheric Research Program and the Office of Climate Dynarics, Divisic

  14. Armed Services Vocational Aptitude Battery: Differential Item Functioning on the High School Form.

    DTIC Science & Technology

    1988-04-01

    AD-RI93 693 ARMED SERVICES VOCATIONAL APTITUDE BATTERY:1/ DIFFERENTIAL ITEM FUNCTIONING..(U) UNIYERSAL ENERGY SYSTEMS INC DAYTON OH R L LINN ET AL...FUNCTIONING ON THE HIGH SCHOOL FORM - H U Robert L. Linn C. Nicholas Hastings Pei-Hua Gillian HuMKatherine E. Ryan A Universal Energy Systems , Inc. 40 Dayton...Period October 1985 - Ky 1987 0 U Approved for public release; distribution is unlimited. R ,. CES LABORATORY 1>2 Se DTIC AIR FORCE SYSTEMS COMMAND 0

  15. The British Armed Forces Covenant - Protection for Tommy or a Civil Military Battleground

    DTIC Science & Technology

    2012-04-01

    he would have been happy to hasten a General Election, which, in his mind, would have been for the good of both the country and the British Army...ire of the Labour government and probably expected to be fired for his actions. Matthew Paris of the [London] Times newspaper noted, “General Dannatt...winnable, as the historian Max Hasting stated in the Times “the British [ Labour ] Government has become increasingly cynical about its own war and

  16. Advancements in Radio Frequency (RF) Photonics for Signal Processing Applications on Avionic Platforms (Preprint)

    DTIC Science & Technology

    2013-10-01

    links and their impact on device design,” IEEE Trans. Microwave Theory and Tech., 54, pp. 906-920, 2006. [2] V. Urick , F. Bucholtz, P. Devgan, J...photonic links,” IEEE Trans. Microwave Theory and Tech., 55, pp. 1978-1985, 2007. [3] P. Devgan, J. Diehl, V. Urick , C. Sunderman, and K. Williams...outputs," Opt. Express, 17, pp. 9028-9039, 2009. [4] P. Devgan, A. Hastings, V. Urick , and K. Williams, "Cancellation of photodiode-induced second

  17. Orbital Debris: Technical and Legal Issues and Solutions

    DTIC Science & Technology

    2006-08-01

    States will seek to minimize the creation of space debris. NASA, the intelligence community, and DoD, in cooperation with the private sector, will...205 and accompanying text. 388 Raymond T. Swenson, “Pollution of the Extraterrestrial Environment” (1985) 25 A.F. L. Rev. 70 at 79. “Article IX is...Hastings Int’l & Comp. L. Rev. 125. Swenson, Raymond T. “Pollution of the Extraterrestrial Environment” (1985) 25 A.F. L. Rev. 70. Tan, David

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

    DTIC Science & Technology

    1975-08-01

    T h revr se o f: t h i p a g is b la n k ) r : -- : : - -= : - -- . .. IM TABLE OF CONTENTS Section Title Page ji I INTRODUCTION ...of merit, ,, in watts/steradian/gram/second, computed from the radiometer data (8) The infrared augmentation ratio ( Jaug /J)flow is the ratio of the

  19. Less haste, less waste: on recycling and its limits in strand displacement systems

    PubMed Central

    Condon, Anne; Hu, Alan J.; Maňuch, Ján; Thachuk, Chris

    2012-01-01

    We study the potential for molecule recycling in chemical reaction systems and their DNA strand displacement realizations. Recycling happens when a product of one reaction is a reactant in a later reaction. Recycling has the benefits of reducing consumption, or waste, of molecules and of avoiding fuel depletion. We present a binary counter that recycles molecules efficiently while incurring just a moderate slowdown compared with alternative counters that do not recycle strands. This counter is an n-bit binary reflecting Gray code counter that advances through 2n states. In the strand displacement realization of this counter, the waste—total number of nucleotides of the DNA strands consumed—is polynomial in n, the number of bits of the counter, while the waste of alternative counters grows exponentially in n. We also show that our n-bit counter fails to work correctly when many (Θ(n)) copies of the species that represent the bits of the counter are present initially. The proof applies more generally to show that in chemical reaction systems where all but one reactant of each reaction are catalysts, computations longer than a polynomial function of the size of the system are not possible when there are polynomially many copies of the system present. PMID:22649584

  20. Molecular cloning, expression and first antigenic characterization of human astrovirus VP26 structural protein and a C-terminal deleted form.

    PubMed

    Royuela, Enrique; Sánchez-Fauquier, Alicia

    2010-01-01

    The open reading frame 2 (ORF2) of human astrovirus (HAstV) encodes the structural VP26 protein that seems to be the main antigenic viral protein. However, its functional role remains unclear. Bioinformatic predictions revealed that VP29 and VP26 proteins could be involved in virus-cell interaction. In this study, we describe for the first time the cloning and expression in Escherichia coli (E. coli) of a recombinant VP26 (rVP26) protein and a VP26 C-terminal truncated form (VP26 Delta C), followed by purification by NTA-Ni(2+) agarose affinity chromatography. Protein expression and purification were evaluated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot (WB). Then, the purified proteins were evaluated for antigenic properties in enzyme linked immunosorbent assay (ELISA) using a polyclonal antibody (PAb) and a neutralizing monoclonal antibody (nMAb) named PL2, both of them directed to HAstV. The results presented herein indicate that the C-terminal end of the VP26 protein is essential to maintain the neutralizing epitope recognized by nMAb PL2 and that the N-terminus of VP26 protein may contain antigenic lineal-epitopes recognized by PAb. Thus, these recombinant proteins can be ideal tools for further antigenic, biochemical, structural and functional VP26 protein characterization, in order to evaluate its potential role in immunodiagnosis and vaccine studies.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hou Fengji; Hogg, David W.; Goodman, Jonathan

    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 approximatelymore » 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.« less

  2. 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.

  3. 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

  4. Chemiluminescence of Organic Compounds.

    DTIC Science & Technology

    1981-04-07

    of organic reaction chemiluminescence (Rauiht, 197) ; Hastings and Wilson, 1976 ; Gundermann, 1974 ; White et al., 1974 ; McCapra, 1973 ; .oto, 1979...1977; Wilson, T., 1976; Turro et al., JI U4a; Mumtord, 1915), the chemiluminescence -4- of hydrazides (Roswell and White , 1978 ; White and Roswell...mechanical Iv exc, it cd . iii; q ie ed in a react inn, meaning energv is released in period ot t ime noi the *r?-!tcr of Ol I ess than thle t ime of a

  5. UH-USA Agreement - A Telemedicine Research Proposal

    DTIC Science & Technology

    2004-11-01

    hold and they were going to quarantine the entire airport. From his description, I explained that it probably was not smallpox but rather chicken pox ...but I still had to come over to examine the patient. I left my busy office, drove post haste to the airport, and confirmed that it was indeed chicken ... pox . No need for quarantine, and the planes resumed their schedules, although a bit late. I thought it would be so nice if the airport medical

  6. Advanced Catalytic Combustors for Low Pollutant Emissions

    DTIC Science & Technology

    1979-11-01

    liner materials in both designs are sheet or forged HS188 . This alloy was designed for stability of the microstructure and properties during heat...625 Inco 718 I: Inca 625 HS188 L605 Hast X Figure 37. Catalytic Combustor Materials. 111 &I ~ 4 L. ,.Add. R service. The hot corrosion resistance of... HS188 is similar to L605 and somewhat F better than Hastelloy X, another common liner material. HS188 exhibits good low cyclo fatigue resistance up to

  7. Worldwide Report, Arms Control.

    DTIC Science & Technology

    1985-11-22

    dinosaurs (and a large number of other species which disappeared "simultaneously") might have become extinct because a large comet hit the earth’s...clear yet aeain the reasons why Washington is in such haste in the arms race for "star wars" and why it refuses to assume a commitment not to be...Kolesnichenko says: [Begin Kolesnichenko recording in Russian with English translation] In an effort to calm the American public and provide a logical reason

  8. Foreign bodies in the aerodigestive tract.

    PubMed

    Lawson, V G; Middleton, W G

    1986-04-01

    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.

  9. Echocardiographic identification of ventricular septal rupture caused by acute stent thrombosis.

    PubMed

    Garg, Scot; Bourantas, Christos V; Thackray, Simon; Alamgir, Mohamed F

    2010-05-01

    Coronary stenting is an increasingly common procedure. Complications are rare. However, when they do occur, they often require urgent invasive treatment. Investigations that are critical for establishing a diagnosis as well as such guide treatment as a detailed assessment of myocardial morphology and function using transthoracic echocardiography may be overlooked in the haste to treat the patient. We present a case report of subacute drug-eluting stent thrombosis in which a meticulous echocardiographic examination allowed the identification of a ventricular septal rupture, which ultimately modified treatment.

  10. 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.

  11. 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).

  12. 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).

  13. A Prototype Climate Information System

    DTIC Science & Technology

    1993-01-01

    accessing the fields used for matching. The relational data base model was developed in the early 1970s by Edgar F . Codd , has become the most important...Thetr goal ofd tisp earh iTESS(3), and porting this software to TESS(3) hasT he go al o f th is research is to develop a C IS tob e u . C I A T d m o...meteorological observations every three hours around the clock. Lt. Matthew F . Maury, upon taking command of the depot in July of 1842, found that the resultant

  14. [Physician and autonomy: on time perception and job satisfaction].

    PubMed

    Huisman, Frank G

    2015-01-01

    Is it true that haste is sneaking into medicine? In this article, it is argued that it mainly concerns the perception of being rushed, which is caused by a loss of autonomy of the modern physician. In the fifties, physicians were busy as well, but because they enjoyed a greater degree of autonomy compared to their contemporary colleagues, they did not experience this in a negative way. Due to increased bureaucracy and the introduction of market dynamics, the medical profession has lost autonomy, which in turn led to a loss of job satisfaction.

  15. 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.

  16. The Analytic Hierarchy Process: Enhancing Operational Level Decision Making

    DTIC Science & Technology

    1993-03-10

    USN 13 TPEOFWO713b. ?WE COVERED 4L. DAT! OF, RIM" ( fta *. NWkO Isi P*MA 001MFAMo to__ / izI 16. SUP"LE MNIARY NOTATION A p ibaikitted the Pl Faat o b...TakQrce The FaajdsWar,.9-82 (New York: Viking Penguin , Inc, Rev. ed., 1988). 26 1. MISSION. To seize the Falkland Islands and eject Argentinian...Falklands War4 1982 (New York: Viking Penguin , Inc, Rev. ed., 1988). Max Hastings and Simon Jenkins, The Battle for the Falklands (New York: W. W. Norton

  17. Genetics and bioethics: how our thinking has changed since 1969.

    PubMed

    Walters, LeRoy

    2012-02-01

    In 1969, the field of human genetics was in its infancy. Amniocentesis was a new technique for prenatal diagnosis, and a newborn genetic screening program had been established in one state. There were also concerns about the potential hazards of genetic engineering. A research group at the Hastings Center and Paul Ramsey pioneered in the discussion of genetics and bioethics. Two principal techniques have emerged as being of enduring importance: human gene transfer research and genetic testing and screening. This essay tracks the development and use of these techniques and considers the ethical issues that they raise.

  18. Discrete Spin Vector Approach for Monte Carlo-based Magnetic Nanoparticle Simulations

    NASA Astrophysics Data System (ADS)

    Senkov, Alexander; Peralta, Juan; Sahay, Rahul

    The study of magnetic nanoparticles has gained significant popularity due to the potential uses in many fields such as modern medicine, electronics, and engineering. To study the magnetic behavior of these particles in depth, it is important to be able to model and simulate their magnetic properties efficiently. Here we utilize the Metropolis-Hastings algorithm with a discrete spin vector model (in contrast to the standard continuous model) to model the magnetic hysteresis of a set of protected pure iron nanoparticles. We compare our simulations with the experimental hysteresis curves and discuss the efficiency of our algorithm.

  19. Padé approximations for Painlevé I and II transcendents

    NASA Astrophysics Data System (ADS)

    Novokshenov, V. Yu.

    2009-06-01

    We use a version of the Fair-Luke algorithm to find the Padé approximate solutions of the Painlevé I and II equations. We find the distributions of poles for the well-known Ablowitz-Segur and Hastings-McLeod solutions of the Painlevé II equation. We show that the Boutroux tritronquée solution of the Painleé I equation has poles only in the critical sector of the complex plane. The algorithm allows checking other analytic properties of the Painlevé transcendents, such as the asymptotic behavior at infinity in the complex plane.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Agnihotri, Newal

    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.

  2. 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.

  3. The Future of Reproductive Autonomy.

    PubMed

    Johnston, Josephine; Zacharias, Rachel L

    2017-12-01

    In a project The Hastings Center is now running on the future of prenatal testing, we are encountering clear examples, both in established law and in the practices of individual providers, of failures to respect women's reproductive autonomy: when testing is not offered to certain demographics of women, for instance, or when the choices of women to terminate or continue pregnancies are prohibited or otherwise not supported. But this project also raises puzzles for reproductive autonomy. We have learned that some clinicians and patients do not discuss the fact that prenatal testing can lead to a decision about whether to terminate a pregnancy-they just don't talk about it. And while the decision whether to agree to prenatal screening and diagnostic testing is to be made with women's free and informed consent, many screening tests have been routinized in such a way that some women do not even recall agreeing to testing, while others feel that agreeing to testing is what their clinicians expect of them or that the testing is necessary to protect themselves and their families from the significant financial hardship of raising a child with a disability. In the face of these pressures, can one really say that women are freely choosing to undergo testing or are freely choosing to continue or terminate a pregnancy following receipt of test results? The reality of these pressures is requiring us to consider expanding the scope of our investigation beyond the clinical encounter to the broader context-to think harder about what reproductive autonomy means and how best to enhance it. © 2017 The Hastings Center.

  4. Preoperative detection of malignant liver tumors: Comparison of 3D-T2-weighted sequences with T2-weighted turbo spin-echo and single shot T2 at 1.5 T.

    PubMed

    Barat, Maxime; Soyer, Philippe; Dautry, Raphael; Pocard, Marc; Lo-Dico, Rea; Najah, Haythem; Eveno, Clarisse; Cassinotto, Christophe; Dohan, Anthony

    2018-03-01

    To assess the performances of three-dimensional (3D)-T2-weighted sequences compared to standard T2-weighted turbo spin echo (T2-TSE), T2-half-Fourier acquisition single-shot turbo spin-echo (T2-HASTE), diffusion weighted imaging (DWI) and 3D-T1-weighted VIBE sequences in the preoperative detection of malignant liver tumors. From 2012 to 2015, all patients of our institution undergoing magnetic resonance imaging (MRI) examination for suspected malignant liver tumors were prospectively included. Patients had contrast-enhanced 3D-T1-weighted, DWI, 3D-T2-SPACE, T2-HASTE and T2-TSE sequences. Imaging findings were compared with those obtained at follow-up, surgery and histopathological analysis. Sensitivities for the detection of malignant liver tumors were compared for each sequence using McNemar test. A subgroup analysis was conducted for HCCs. Image artifacts were analyzed and compared using Wilcoxon paired signed rank-test. Thirty-three patients were included: 13 patients had 40 hepatocellular carcinomas (HCC) and 20 had 54 liver metastases. 3D-T2-weighted sequences had a higher sensitivity than T2-weighted TSE sequences for the detection of malignant liver tumors (79.8% versus 68.1%; P < 0.001). The difference did not reach significance for HCC. T1-weighted VIBE and DWI had a higher sensitivity than T2-weighted sequences. 3D-T2-weighted-SPACE sequences showed significantly less artifacts than T2-weitghted TSE. 3D-T2-weighted sequences show very promising performances for the detection of liver malignant tumors compared to T2-weighted TSE sequences. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. REAL TIME MRI GUIDED RADIOFREQUENCY ATRIAL ABLATION AND VISUALIZATION OF LESION FORMATION AT 3-TESLA

    PubMed Central

    Vergara, Gaston R.; Vijayakumar, Sathya; Kholmovski, Eugene G.; Blauer, Joshua J.E.; Guttman, Mike A.; Gloschat, Christopher; Payne, Gene; Vij, Kamal; Akoum, Nazem W.; Daccarett, Marcos; McGann, Christopher J.; MacLeod, Rob S.; Marrouche, Nassir F.

    2011-01-01

    Background MRI allows visualization of location and extent of RF ablation lesion, myocardial scar formation, and real-time (RT) assessment of lesion formation. In this study, we report a novel 3-Tesla RT-MRI based porcine RF ablation model and visualization of lesion formation in the atrium during RF energy delivery. Objective To develop of a 3-Tesla RT-MRI based catheter ablation and lesion visualization system. Methods RF energy was delivered to six pigs under RT-MRI guidance. A novel MRI compatible mapping and ablation catheter was used. Under RT-MRI this catheter was safely guided and positioned within either the left or right atrium. Unipolar and bi-polar electrograms were recorded. The catheter tip-tissue interface was visualized with a T1-weighted gradient echo sequence. RF energy was then delivered in a power-controlled fashion. Myocardial changes and lesion formation were visualized with a T2-weighted (T2w) HASTE sequence during ablation. Results Real-time visualization of lesion formation was achieved in 30% of the ablations performed. In the other cases, either the lesion was formed outside the imaged region (25%) or lesion was not created (45%) presumably due to poor tissue-catheter tip contact. The presence of lesions was confirmed by late gadolinium enhancement (LGE) MRI and macroscopic tissue examination. Conclusion MRI compatible catheters can be navigated and RF energy safely delivered under 3-Tesla RT-MRI guidance. It is also feasible to record electrograms during RT imaging. Real-time visualization of lesion as it forms during delivery of RF energy is possible and was demonstrated using T2w HASTE imaging. PMID:21034854

  6. 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.

  7. Rapid recipe formulation for plasma etching of new materials

    NASA Astrophysics Data System (ADS)

    Chopra, Meghali; Zhang, Zizhuo; Ekerdt, John; Bonnecaze, Roger T.

    2016-03-01

    A fast and inexpensive scheme for etch rate prediction using flexible continuum models and Bayesian statistics is demonstrated. Bulk etch rates of MgO are predicted using a steady-state model with volume-averaged plasma parameters and classical Langmuir surface kinetics. Plasma particle and surface kinetics are modeled within a global plasma framework using single component Metropolis Hastings methods and limited data. The accuracy of these predictions is evaluated with synthetic and experimental etch rate data for magnesium oxide in an ICP-RIE system. This approach is compared and superior to factorial models generated from JMP, a software package frequently employed for recipe creation and optimization.

  8. Monte Carlo simulation of a noisy quantum channel with memory.

    PubMed

    Akhalwaya, Ismail; Moodley, Mervlyn; Petruccione, Francesco

    2015-10-01

    The classical capacity of quantum channels is well understood for channels with uncorrelated noise. For the case of correlated noise, however, there are still open questions. We calculate the classical capacity of a forgetful channel constructed by Markov switching between two depolarizing channels. Techniques have previously been applied to approximate the output entropy of this channel and thus its capacity. In this paper, we use a Metropolis-Hastings Monte Carlo approach to numerically calculate the entropy. The algorithm is implemented in parallel and its performance is studied and optimized. The effects of memory on the capacity are explored and previous results are confirmed to higher precision.

  9. 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.

  10. [Determining acid phosphatase (AcP[E.C. 3.1.3.2.]) and adenosine triphosphatase (ATPase [E.C. 3.6.1.3.]) activity in the lungs of rats following a single administration of ashes from industrial high-heat facilities].

    PubMed

    Romanowska-Sarlej, J; Staszyc, J; Królikowska-Prasał, I; Jedrzejewska, E; Kifer, E; Matysiak, W

    1988-01-01

    There was examined pulmonary tissue of white rats, which had been administered intratrachealy a single dose of the respirable fraction of ashes sample from 6 different power stations elektrohasting plants and hasting plants in Poland (0.2 ml suspension; 50 mg of the examined sample in 0.6 cm3 of NaCl solution). 9 months after the application of the ashes, biopsies of the left lung were taken and there was determined the activity of acid phosphatase (AcP) and adenosinetriphosphatase (ATP-ase) histoenzymatically. There was found sensitivity of these hydrolases and changes of their activity connected with chemical composition of the examined ashes.

  11. 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.

  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. 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…

  15. 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.

  16. 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.

  17. Improving both imaging speed and spatial resolution in MR-guided neurosurgery

    NASA Astrophysics Data System (ADS)

    Liu, Haiying; Hall, Walter A.; Truwit, Charles L.

    2002-05-01

    A robust near real-time MRI based surgical guidance scheme has been developed and used in neurosurgical procedure performed in our combined 1.5 Tesla MR operating room. Because of the increased susceptibility difference in the area of surgical site during surgery, the preferred real- time imaging technique is a single shot imaging sequence based on the concept of the half acquisition with turbo spin echoes (HASTE). In order to maintain sufficient spatial resolution for visualizing the surgical devices, such as a biopsy needle and catheter, we used focused field of view (FOV) in the phase-encoding (PE) direction coupled with an out-volume signal suppression (OVS) technique. The key concept of the method is to minimize the total number of the required phase encoding steps and the effective echo time (TE) as well as the longest TE for the high spatial encoding step. The concept has been first demonstrated with a phantom experiment, which showed when the water was doped with Gd- DTPA to match the relaxation rates of the brain tissue there was a significant spatial blurring primarily along the phase encoding direction if the conventional HASTE technique, and the new scheme indeed minimized the spatial blur in the resulting image and improved the needle visualization as anticipated. Using the new scheme in a typical MR-guided neurobiopsy procedure, the brain biopsy needle was easily seen against the tissue background with minimal blurring due the inevitable T2 signal decay even when the PE direction was set parallel to the needle axis. This MR based guidance technique has practically allowed neurosurgeons to visualize the biopsy needle and to monitor its insertion with a better certainty at near real-time pace.

  18. Real-time magnetic resonance imaging-guided radiofrequency atrial ablation and visualization of lesion formation at 3 Tesla.

    PubMed

    Vergara, Gaston R; Vijayakumar, Sathya; Kholmovski, Eugene G; Blauer, Joshua J E; Guttman, Mike A; Gloschat, Christopher; Payne, Gene; Vij, Kamal; Akoum, Nazem W; Daccarett, Marcos; McGann, Christopher J; Macleod, Rob S; Marrouche, Nassir F

    2011-02-01

    Magnetic resonance imaging (MRI) allows visualization of location and extent of radiofrequency (RF) ablation lesion, myocardial scar formation, and real-time (RT) assessment of lesion formation. In this study, we report a novel 3-Tesla RT -RI based porcine RF ablation model and visualization of lesion formation in the atrium during RF energy delivery. The purpose of this study was to develop a 3-Tesla RT MRI-based catheter ablation and lesion visualization system. RF energy was delivered to six pigs under RT MRI guidance. A novel MRI-compatible mapping and ablation catheter was used. Under RT MRI, this catheter was safely guided and positioned within either the left or right atrium. Unipolar and bipolar electrograms were recorded. The catheter tip-tissue interface was visualized with a T1-weighted gradient echo sequence. RF energy was then delivered in a power-controlled fashion. Myocardial changes and lesion formation were visualized with a T2-weighted (T2W) half Fourier acquisition with single-shot turbo spin echo (HASTE) sequence during ablation. RT visualization of lesion formation was achieved in 30% of the ablations performed. In the other cases, either the lesion was formed outside the imaged region (25%) or the lesion was not created (45%) presumably due to poor tissue-catheter tip contact. The presence of lesions was confirmed by late gadolinium enhancement MRI and macroscopic tissue examination. MRI-compatible catheters can be navigated and RF energy safely delivered under 3-Tesla RT MRI guidance. Recording electrograms during RT imaging also is feasible. RT visualization of lesion as it forms during RF energy delivery is possible and was demonstrated using T2W HASTE imaging. Copyright © 2011 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  19. TU-F-BRF-06: 3D Pancreas MRI Segmentation Using Dictionary Learning and Manifold Clustering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gou, S; Rapacchi, S; Hu, P

    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 dictionarymore » 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.« less

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doug Cathro

    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 andmore » 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

  1. 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.

  2. 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

  3. 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.

  4. Gender, identity, and bioethics.

    PubMed

    Dietz, Elizabeth A

    2016-07-01

    Transgender people and issues have come to the forefront of public consciousness over the last year. Caitlyn Jenner' very public transition, heightened media coverage of the murders of transgender women of color, and the panicked passage of North Carolina's "bathroom bill" (House Bill 2), mean that conversations about transgender health and well-being are no longer happening only within small communities. The idea that transgender issues are bioethical issues is not new, but I think that increased public awareness of transgender people and the ways that their health is affected by systems that bioethics already engages with offers an opportunity for scholarship that works to improve transgender health in meaningful ways. © 2016 The Hastings Center.

  5. Just What Is the Disability Perspective on Disability?

    PubMed

    Shakespeare, Tom

    2016-05-01

    In the helpful article "Why Bioethics Needs a Disability Moral Psychology," Joseph Stramondo adds to the critique of actually existing bioethics and explains why disability activists and scholars so often find fault with the arguments of bioethicists. He is careful not to stereotype either community-rightly, given that bioethicists endorse positions as disparate as utilitarianism, deontology, virtue ethics, and feminist ethics, among others. Although Stramondo never explicitly mentions utilitarians or liberals, it seems probable that these are the main targets of his discontent. The disability community, as he concedes, is also a broad church. Yet for this reason, I do not believe that you can read off positions on bioethics questions from either disability embodiment or disability organization affiliation. © 2016 The Hastings Center.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Torfason, Kristinn; Valfells, Agust; Manolescu, Andrei

    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 likemore » model is also developed and its results are in qualitative agreement with the simulations.« less

  7. Stable schemes for dissipative particle dynamics with conserved energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stoltz, Gabriel, E-mail: stoltz@cermics.enpc.fr

    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 multiplemore » timestep strategies where the stochastic part is integrated less frequently than the Hamiltonian one.« less

  8. Regulating Research with Biospecimens under the Revised Common Rule.

    PubMed

    Lynch, Holly Fernandez; Meyer, Michelle N

    2017-05-01

    Since 2011, the research community had waited with bated breath as regulators contemplated for the first time bringing secondary research with nonidentifiable biospecimens under the Common Rule and dramatically tightening the criteria for waiving consent to biospecimen research. After considerable pushback from both researchers and patients and amid rumors of intractable disagreement among Common Rule agencies, the Final Rule published on the last day of President Obama's administration left out these troubling changes, and there was a collective sigh of relief. Relief is appropriate, but celebration premature: researchers have little reason to avail themselves of the new broad consent option offered in the Final Rule, and the question of whether biospecimens ought to be treated as inherently identifiable has merely been postponed. © 2017 The Hastings Center.

  9. 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.

  10. Diagnosis of hepatic metastasis: comparison of respiration-triggered diffusion-weighted echo-planar MRI and five t2-weighted turbo spin-echo sequences.

    PubMed

    Bruegel, Melanie; Gaa, Jochen; Waldt, Simone; Woertler, Klaus; Holzapfel, Konstantin; Kiefer, Berthold; Rummeny, Ernst J

    2008-11-01

    The purpose of this study was to compare the value of respiration-triggered diffusion-weighted (DW) single-shot echo-planar MRI (EPI) and five variants of T2-weighted turbo spin-echo (TSE) sequences in the diagnosis of hepatic metastasis. Fifty-two patients with extrahepatic primary malignant tumors underwent 1.5-T MRI that included DW EPI and the following variants of T2-weighted TSE techniques: breath-hold fat-suppressed HASTE, breath-hold fat-supressed TSE, respiration-triggered fat-suppressed TSE, breath-hold STIR, and respiration-triggered STIR. Images were reviewed independently by two blinded observers who used a 5-point confidence scale to identify lesions. Results were correlated with surgical and histopathologic findings and follow-up imaging findings. The accuracy of each technique was measured with free-response receiver operating characteristic analysis. A total of 118 hepatic metastatic lesions (mean diameter, 12.8 mm; range, 3-84 mm) were evaluated. Accuracy values were higher (p < 0.001) with DW EPI (0.91-0.92) than with the T2-weighted TSE techniques (0.47-0.67). Imaging with the HASTE sequence (0.47-0.52) was less accurate (p < 0.05) than imaging with the breath-hold TSE, breath-hold STIR, respiration-triggered TSE, and respiration-triggered STIR sequences (0.59-0.67). Sensitivity was higher (p < 0.001) with DW EPI (0.88-0.91) than with T2-weighted TSE techniques (0.45-0.62). For small (< or = 10 mm) metastatic lesions only, the differences in sensitivity between DW EPI (0.85) and T2-weighted TSE techniques (0.26-0.44) were even more pronounced. DW EPI was more sensitive and more accurate than imaging with T2-weighted TSE techniques. Because of the black-blood effect on vessels and low susceptibility to motion artifacts, DW EPI was particularly useful for the detection of small (< or = 10 mm) metastatic lesions.

  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

    ... regular business hours (7 CFR 1.27(c)). FOR FURTHER INFORMATION CONTACT: Karen W. Guagliardo, 202-720-8262... State line east; Bounded on the East by the eastern South Dakota State line (the Big Sioux River) to... contiguous [[Page 15938

  12. 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

    ... DEPARTMENT OF AGRICULTURE Grain Inspection, Packers and Stockyards Administration Designation for... Carolina Areas AGENCY: Grain Inspection, Packers and Stockyards Administration, USDA. ACTION: Notice. SUMMARY: GIPSA is announcing the designation of Aberdeen Grain Inspection, Inc. (Aberdeen); Decatur Grain...

  13. Evolutionarily stable and convergent stable strategies in reaction-diffusion models for conditional dispersal.

    PubMed

    Lam, King-Yeung; Lou, Yuan

    2014-02-01

    We consider a mathematical model of two competing species for the evolution of conditional dispersal in a spatially varying, but temporally constant environment. Two species are different only in their dispersal strategies, which are a combination of random dispersal and biased movement upward along the resource gradient. In the absence of biased movement or advection, Hastings showed that the mutant can invade when rare if and only if it has smaller random dispersal rate than the resident. When there is a small amount of biased movement or advection, we show that there is a positive random dispersal rate that is both locally evolutionarily stable and convergent stable. Our analysis of the model suggests that a balanced combination of random and biased movement might be a better habitat selection strategy for populations.

  14. Trustworthy Research Institutions: The Challenging Case of Studying the Genetics of Intelligence.

    PubMed

    Johnston, Josephine; Banerjee, Mohini P; Geller, Gail

    2015-01-01

    It is simple enough to claim that academic research institutions ought to be trustworthy. Building the culture and taking the steps necessary to earn and preserve institutional trust are, however, complex processes. The experience motivating this special report--a request for the Center for Talented Youth at Johns Hopkins University to collaborate on research regarding the genetics of intelligence--illustrates how ensuring institutional trustworthiness can be in tension with a commitment to fostering research. In this essay, we explore the historical context for biomedical research institutions like Johns Hopkins that have worked to build local community trust. In so doing, we consider how the example under focus in this special report can lead to greater consideration of how research institutions balance fostering trust with their other commitments. © 2015 The Hastings Center.

  15. Hamiltonian Markov Chain Monte Carlo Methods for the CUORE Neutrinoless Double Beta Decay Sensitivity

    NASA Astrophysics Data System (ADS)

    Graham, Eleanor; Cuore Collaboration

    2017-09-01

    The CUORE experiment is a large-scale bolometric detector seeking to observe the never-before-seen process of neutrinoless double beta decay. Predictions for CUORE's sensitivity to neutrinoless double beta decay allow for an understanding of the half-life ranges that the detector can probe, and also to evaluate the relative importance of different detector parameters. Currently, CUORE uses a Bayesian analysis based in BAT, which uses Metropolis-Hastings Markov Chain Monte Carlo, for its sensitivity studies. My work evaluates the viability and potential improvements of switching the Bayesian analysis to Hamiltonian Monte Carlo, realized through the program Stan and its Morpho interface. I demonstrate that the BAT study can be successfully recreated in Stan, and perform a detailed comparison between the results and computation times of the two methods.

  16. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-12-08

    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. 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.

  18. Bioethics and Populism: How Should Our Field Respond?

    PubMed

    Solomon, Mildred Z; Jennings, Bruce

    2017-03-01

    Across the world, an authoritarian and exclusionary form of populism is gaining political traction. Historically, some populist movements have been democratic and based on a sense of inclusive justice and the common good. But the populism on the rise at present speaks and acts otherwise. It is challenging constitutional democracies. The polarization seen in authoritarian populism goes beyond the familiar left-right political spectrum and generates disturbing forms of extremism, including the so-called alternative right in the United States and similar ethnic and nationalistic political movements in other countries. The field of bioethics will be profoundly affected if authoritarian populism displaces constitutional democracy. But the field has a significant contribution to make to rebuilding the communal and civic foundations upon which constitutional democracy rests. © 2017 The Hastings Center.

  19. The Limits of Surrogates' Moral Authority and Physician Professionalism: Can the Paradigm of Palliative Sedation Be Instructive?

    PubMed

    Berger, Jeffrey T

    2017-01-01

    With narrow exception, physicians' treatment of incapacitated patients requires the consent of health surrogates. Although the decision-making authority of surrogates is appropriately broad, their moral authority is not without limits. Discerning these bounds is particularly germane to ethically complex treatments and has important implications for the welfare of patients, for the professional integrity of clinicians, and, in fact, for the welfare of surrogates. Palliative sedation is one such complex treatment; as such, it provides a valuable model for analyzing the scope of surrogates' moral authority. Guidelines for palliative sedation that present it as a "last-resort" treatment for severe and intractable suffering yet require surrogate consent in order to offer it are ethically untenable, precisely because the moral limits of surrogate authority have not been considered. © 2017 The Hastings Center.

  20. The social transformation of some American ethics committees.

    PubMed

    Cohen, C B

    1989-01-01

    The relationship between ethics committees and the institutions in which they function is the topic of this edition of the Hastings Center Report's biannual "Ethics committees" column. Cohen introduces the column, commenting upon the trend toward institutional control of all aspects of health care delivered within their walls, including the activities of ethics committees. Contributions include Daniel Wikler's "Institutional agendas and ethics committees," Evelyn Van Allen, D. Gay Moldow, and Ronald Cranford's "Evaluating ethics committees," and the case study "Committee consultation to override family wishes," with a commentary by David Gary Smith. Two legal notes conclude the column: "New Jersey -- still the nation's proving ground?" by Paul W. Armstrong, and "The Philadelphia story," by Willard Green, on the results of the Delaware Valley Ethics Committee Network's survey of ethics committees' needs and policies.

  1. Reproductive technology: in Britain, the debate after the Warnock Report.

    PubMed

    Gillon, Raanan

    1987-06-01

    Gillon contributes an article on Great Britain to the Hastings Center Report series on reproductive technologies outside the United States. In 1984 the Warnock Committee's report represented the first attempt by a national government to formulate a policy on reproductive issues such as artificial insemination, in vitro fertilization, surrogate mothers, and research on human embryos. Reaction to the Warnock report has focused on its recommendations to ban commercial surrogacy and to allow experimentation on embryos up to 14 days after fertilization. Legislation on surrogacy was passed in 1985, while bills banning embryo research failed in 1986. A 1986 government consultation paper called for discussion of other aspects of the Warnock report, including its recommendation that a statutory licensing authority to regulate reproductive technologies be established. Gillon predicts that no new legislation will be enacted under the present government.

  2. [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.

  3. Flu, Floods, and Fire: Ethical Public Health Preparedness.

    PubMed

    Phelan, Alexandra L; Gostin, Lawrence O

    2017-05-01

    Even as public health ethics was developing as a field, major incidents such as 9/11 and the SARS epidemic propelled discourse around public health emergency preparedness and response. Policy and practice shifted to a multidisciplinary approach, recognizing the broad range of potential threats to public health, including biological, physical, radiological, and chemical threats. This propelled the development of surveillance systems to detect incidents, laboratory capacities to rapidly test for potential threats, and therapeutic and social countermeasures to prepare for and respond to a range of hazards. In bringing public health ethics and emergency preparedness together, Emergency Ethics: Public Health Preparedness and Response adds depth and complexity to both fields. As global threats continue to emerge, the book, edited by Bruce Jennings, John D. Arras, Drue H. Barrett, and Barbara A. Ellis, will offer a vital compass. © 2017 The Hastings Center.

  4. Magnetic resonance imaging of placenta accreta

    PubMed Central

    Varghese, Binoj; Singh, Navdeep; George, Regi A.N; Gilvaz, Sareena

    2013-01-01

    Placenta accreta (PA) is a severe pregnancy complication which occurs when the chorionic villi (CV) invade the myometrium abnormally. Optimal management requires accurate prenatal diagnosis. Ultrasonography (USG) and magnetic resonance imaging (MRI) are the modalities for prenatal diagnosis of PA, although USG remains the primary investigation of choice. MRI is a complementary technique and reserved for further characterization when USG is inconclusive or incomplete. Breath-hold T2-weighted half-Fourier rapid acquisition with relaxation enhancement (RARE) and balanced steady-state free precession imaging in the three orthogonal planes is the key MRI technique. Markedly heterogeneous placenta, thick intraplacental dark bands on half-Fourier acquisition single-shot turbo spin-echo (HASTE), and disorganized abnormal intraplacental vascularity are the cardinal MRI features of PA. MRI is less reliable in differentiating between different degrees of placental invasion, especially between accreta vera and increta. PMID:24604945

  5. Illness as a Crisis of Meaning.

    PubMed

    Hauskeller, Michael

    2018-05-21

    In Phenomenological Bioethics: Medical Technologies, Human Suffering, and the Meaning of Being Alive, the Swedish philosopher Fredrik Svenaeus aims to show how the continental tradition of phenomenology can enrich bioethical debates by adding important but often-ignored perspectives, namely, that of lived experience. Phenomenology focuses not on supposedly objective, scientifically validated facts, but on the "life world" of the individuals affected by a situation. Individuals' life worlds consist of their experience of their own lived bodies (or Leiber) and the meaning structures of their everyday worlds. A phenomenologically informed and oriented bioethics would seek to take those life worlds into account when considering what should be done in a particular ethically challenging situation. The fundamental insight that Svenaeus develops in his new book is that our illnesses are often, if not always, crises of meaning. © 2018 The Hastings Center.

  6. Genetic Information, the Principle of Rescue, and Special Obligations.

    PubMed

    Liao, S Matthew; Mackenzie, Jordan

    2018-05-01

    In "Genetic Privacy, Disease Prevention, and the Principle of Rescue," Madison Kilbride argues that patients have a duty to warn biological family members about clinically actionable adverse genetic findings. The duty does not stem from the special obligations that we may have to family members, she argues, but rather follows from the principle of rescue, which she understands as the idea that one ought to prevent, reduce, or mitigate the risk of harm to another person when the expected harm is serious and the cost or risk to oneself is sufficiently moderate. We doubt, however, whether the principle of rescue can ground a duty to warn in the cases Kilbride envisages, and we suggest that Kilbride may have underappreciated the role that special obligations could play in generating a duty to warn family members. © 2018 The Hastings Center.

  7. 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.

  8. 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.

  9. A sampling algorithm for segregation analysis

    PubMed Central

    Tier, Bruce; Henshall, John

    2001-01-01

    Methods for detecting Quantitative Trait Loci (QTL) without markers have generally used iterative peeling algorithms for determining genotype probabilities. These algorithms have considerable shortcomings in complex pedigrees. A Monte Carlo Markov chain (MCMC) method which samples the pedigree of the whole population jointly is described. Simultaneous sampling of the pedigree was achieved by sampling descent graphs using the Metropolis-Hastings algorithm. A descent graph describes the inheritance state of each allele and provides pedigrees guaranteed to be consistent with Mendelian sampling. Sampling descent graphs overcomes most, if not all, of the limitations incurred by iterative peeling algorithms. The algorithm was able to find the QTL in most of the simulated populations. However, when the QTL was not modeled or found then its effect was ascribed to the polygenic component. No QTL were detected when they were not simulated. PMID:11742631

  10. Liquid fuel supplies

    NASA Astrophysics Data System (ADS)

    Perry, H.

    1980-06-01

    This paper presents an overview of United States and world petroleum, natural gas, and natural gas liquids presumed recoverable but as yet undiscovered resources and suggests that the depletion of these fuels may not occur as quickly as frequently predicted. The paper points out that the construction of a synthetic fuels industry will be very costly and will provide only a small amount of increased energy independence. The fear is expressed that haste in accepting a specific synfuels process on the basis of present technology may serve to forestall the development of a better technology. The paper suggests that we construct relatively few plants now each using a different technology in order to gain better understanding of the various technologies, more information on costs and the essential but as yet unknown information on environmental and socioeconomic effects of large scale plants.

  11. 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

    2018-01-01

    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.

  12. 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,…

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

    NASA Astrophysics Data System (ADS)

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

    2011-08-01

    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.

  14. Groundhog Day for Medical Artificial Intelligence.

    PubMed

    London, Alex John

    2018-05-01

    Following a boom in investment and overinflated expectations in the 1980s, artificial intelligence entered a period of retrenchment known as the "AI winter." With advances in the field of machine learning and the availability of large datasets for training various types of artificial neural networks, AI is in another cycle of halcyon days. Although medicine is particularly recalcitrant to change, applications of AI in health care have professionals in fields like radiology worried about the future of their careers and have the public tittering about the prospect of soulless machines making life-and-death decisions. Medicine thus appears to be at an inflection point-a kind of Groundhog Day on which either AI will bring a springtime of improved diagnostic and predictive practices or the shadow of public and professional fear will lead to six more metaphorical weeks of winter in medical AI. © 2018 The Hastings Center.

  15. Returning Incidental Findings in Low-Resource Settings: A Case of Rescue?

    PubMed

    Mackay, Douglas

    2018-05-01

    In a carefully argued article, Haley K. Sullivan and Benjamin E. Berkman address the important question of whether investigators have a duty to report incidental findings to research participants in low-resource settings. They suggest that the duty to rescue offers the most plausible justification for the duty to return incidental findings, and they explore the implications of this duty for the context of research in low-resource settings. While I think they make valuable headway on an important problem, in this commentary, I identify a significant difference between the paradigmatic rescue case and the return of incidental findings in low-resource settings. This difference, I suggest, implies that their framework may be too narrow in scope. If investigators (and their sponsors) really wish to fulfill their duty to rescue, they must consider factors that are left out of Sullivan and Berkman's framework. © 2018 The Hastings Center.

  16. Markov Chain Monte Carlo from Lagrangian Dynamics.

    PubMed

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

    2015-04-01

    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.

  17. [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.

  18. [Job stress and well-being of care providers: development of a standardized survey instrument].

    PubMed

    Kivimäki, M; Lindström, K

    1992-01-01

    The main aim was to develop a standardized survey instrument for measuring job stress and well-being in hospital settings. The actual study group consisted of 349 workers from medical bed wards, first aid unit wards and bed wards for gynecology and obstetrics in a middle-sized hospital in the Helsinki region. Based on the factor analysis of separate questions, the following content areas were chosen for the job stressor scales: haste at work, problems in interpersonal relations at work, problems in occupational collaboration with others, too much responsibility, safety and health risks, lack of appreciation, troublesome patients, and lack of equipment and resources. Content areas for well-being scales and items were general job satisfaction, strain symptoms, perceived mental and physical work load. The reference values of the questionnaire and reliabilities for the scales were calculated. The application and further development of the questionnaire was discussed.

  19. 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.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hastings, Matthew B

    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, themore » 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.« less

  1. A world without Roe: how different would it be?

    PubMed

    Glendon, M A

    1989-01-01

    In anticipation of the U.S. Supreme Court's decision in Webster v. Reproductive Health Services (3 Jul 1989), this issue of the Hastings Center Report includes articles by Glendon, M. Mahowald, and N. Rhoden under the unifying title "Abortion: searching for common ground." Each author acknowledges the polarization of public and political opinion after the Court's 1973 Roe v. Wade decision, and seeks to establish a common ground in the abortion debate upon which a regulatory structure could be built. Glendon, author of the monograph Abortion and Divorce in Western Law: American Failures, European Challenges (Harvard; 1987), describes Roe as the most permissive abortion law in the industrializled West. She suggests that the United States might look to European laws as models where experience has shown that political compromise is possible when regulating abortion in countries where public opinion on the issue is deeply divided.

  2. Mass Shootings, Mental Illness, and Gun Control.

    PubMed

    Philpott-Jones, Sean

    2018-03-01

    In the wake of the Stoneman Douglas School shooting, Republican and Democratic leaders-like the American electorate they represent-remain sharply divided in their responses to gun violence. They are united in their condemnation of these mass shootings, but they disagree about whether stricter or looser gun control laws are the answer. Those on the right side of the political aisle suggest that the issue is one of mental illness rather than gun control. Conversely, those who are more liberal or progressive in their political learnings are quick to condemn attempts to reframe the issue of mass shootings as a mental health problem. Both sides are wrong. Mass shootings are indeed partially a mental health problem, albeit one poorly addressed by our current laws and policies. But the solution to mass shootings also needs to consider strategies that may reduce gun violence in general. © 2018 The Hastings Center.

  3. 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

  4. Voluntary sterilization for childfree women: understanding patient profiles, evaluating accessibility, examining legislation.

    PubMed

    Richie, Cristina

    2013-01-01

    Approximately 47 percent of women ages fifteen to forty-four are currently without children, and slightly more than 20 percent of white women in America will never bear children, the highest percentage in modern history. Many fertile women who are childless are voluntarily so. Although any competent person twenty-one years or older is legally eligible for voluntary sterilization, many doctors refuse to sterilize childfree women. This essay explores various reasons a woman would want to continue in her childfree lifestyle, evaluates the accessibility of sterilization for women who are childfree by examining the reported reasons for denial of sterilization-both from the woman's and the physician's perspective-and assesses the legal status of voluntary sterilization for nonparous women. The essay also urges physicians to follow recommended guidelines for counseling women who, regardless of parity, desire sterilization and to provide this contraception if, after careful consideration, there are no outstanding health or other reasons that the procedure should not be performed. © 2013 by The Hastings Center.

  5. The root cause of ability and inability to assemble and install components using written manual with or without diagrams among non-native English speakers: Root cause analysis

    NASA Astrophysics Data System (ADS)

    Shukri, S. Ahmad; Millar, R.; Gratton, G.; Garner, M.; Noh, H. Mohd

    2017-12-01

    Documentation errors and human errors are often claimed to be the contributory factors for aircraft maintenance mistakes. This paper highlights the preliminary results of the third phase of a four-phased research on communication media that are utilised in an aircraft maintenance organisation. The second phase has looked into the probability of success and failure in completing a task by 60 subjects while in this third phase, the same subjects have been interviewed immediately after completing the task by using Root Cause Analysis (RCA) method. It is discovered that the root cause of their inability to finish the task while using only written manual is the absence of diagrams. However, haste is identified to be the root cause for the incompletion of the task when both manual and diagram are given to the participants. It is observed that those who are able to complete the task is due to their reference to both manual and diagram, simultaneously.

  6. Ending DACA Has Pragmatic and Ethical Implications for U.S. Health Care.

    PubMed

    Zaidi, Danish; Kuczewski, Mark

    2017-11-01

    In 2012, Loyola University Chicago's Stritch School of Medicine became the first medical school in the United States to actively recruit and accept undocumented immigrants who received protections granted under the Deferred Action for Childhood Arrivals program that was established by presidential memorandum. By 2016, sixty-one medical schools were considering applications from DACA recipients for admission, and more than 110 students applied. According to the American Association of Medical Colleges, sixty-five DACA recipients matriculated in U.S. medical schools in the 2016-2017 school year. These students contribute both diversity and talent to our medical community; they could also have a significant impact on the care of underserved and immigrant populations. The recent decision by the Trump administration to rescind DACA therefore comes with serious pragmatic and ethical ramifications, impeding our medical community's efforts to develop a diverse and representative workforce committed to improving access to quality care for all patients. © 2017 The Hastings Center.

  7. Corporations now included under Section 189

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arlinghaus, B.P.; Anderson, D.T.

    1983-12-01

    This article examines some of the issues, including the ''real property'' question, that corporations may encounter in implementing the provisions of Code Section 189 and its regulations. The extension of 189 to regular corporations represents a significant change in congressional intent, since it was originally enacted as a reform measure and is now primarily a provision to raise revenue at a time when Congress is facing a large dificit. Code Section 189 was conceived and enacted in haste, however, and this expansion will undoubtedly have an adverse impact on capital investment at a time when stimulation is needed for themore » economy as a whole. The workload of the courts and the Internal Revenue Service will certainly increase. Careful drafting of the regulations could anticipate potential issues and clarify them in the drafting stage. The meaning of real property, capitalization rate, capitalization period, and self-constructed assets all need to be carefully addressed. 18 references.« less

  8. Improved one-dimensional area law for frustration-free systems

    NASA Astrophysics Data System (ADS)

    Arad, Itai; Landau, Zeph; Vazirani, Umesh

    2012-05-01

    We present a new proof for the 1D area law for frustration-free systems with a constant gap, which exponentially improves the entropy bound in Hastingsâ 1D area law and which is tight to within a polynomial factor. For particles of dimension d, spectral gap ɛ>0, and interaction strength at most J, our entropy bound is S1D≤O(1)·X3log8X, where X=def(Jlogd)/ɛ. Our proof is completely combinatorial, combining the detectability lemma with basic tools from approximation theory. In higher dimensions, when the bipartitioning area is |∂L|, we use additional local structure in the proof and show that S≤O(1)·|∂L|2log6|∂L|·X3log8X. This is at the cusp of being nontrivial in the 2D case, in the sense that any further improvement would yield a subvolume law.

  9. Bioethics and "Rightness".

    PubMed

    Frank, Arthur W

    2017-03-01

    If bioethics seeks to affect what people do and don't do as they respond to the practical issues that confront them, then it is useful to take seriously people's sense of rightness. Rightness emerges from the fabric of a life-including the economy of its geography, the events of its times, its popular culture-to be what the sociologist Pierre Bourdieu calls a predisposition. It is the product of a way of life and presupposes continuing to live that way. Rightness is local and communal, holding in relationship those who share the same predisposing sense of how to experience. Rightness is an embodied way of evaluating what is known to matter and choosing among possible responses. Bioethics spends considerable time on what people should do and on the arguments that support recommended actions. It might spend more time on what shapes people's sense of the rightness of what they feel called to do. © 2017 The Hastings Center.

  10. Organ Transplantation and the Uniform Anatomical Gift Act: A Fifty-Year Perspective.

    PubMed

    Sadler, Blair L; Sadler, Alfred M

    2018-03-01

    Fifty years ago this summer, the Uniform Anatomical Gift Act was adopted by the National Conference of Commissioners on Uniform State Laws and approved by the American Bar Association. The UAGA has provided a sound and stable legal platform on which to base an effective nationwide organ donation system. The cardinal principles of altruism, autonomy, and public trust are still important. At a time when confidence and trust in our government and many private institutions has declined, maintaining trust and confidence in our health care system and its commitment to "first, do no harm" has never been more important. Any policies that override these core ethical principles could cause irreparable damage to the public's faith in our transplant system. While progress has been made to increase organ registration and the number of organs transplanted, much more must be done to realize the potential of life-saving therapy without jeopardizing ethical principles. © 2018 The Hastings Center.

  11. A new species of freshwater eel-tailed catfish of the genus Tandanus (Teleostei: Plotosidae) from coastal rivers of mid-northern New South Wales, Australia

    USGS Publications Warehouse

    Welsh, Stuart A.; Jerry, Dean R.; Burrows, Damien; Rourke, Meaghan L.

    2017-01-01

    Tandanus bellingerensis, new species, is described based on specimens from four river drainages (Bellinger, Macleay, Hastings, and Manning rivers) of the mid-northern coast of New South Wales, Australia. Previously, three species were recognized in the genus Tandanus: T. tropicanus of the wet tropics region of northeast Queensland, T. tandanus of the Murray-Darling drainage and coastal streams of central-southern Queensland and New South Wales, and T. bostocki of southwestern Western Australia. The new species is distinguished from all congeners by a combination of the following morphologic characters: a high count of rays in the continuous caudodorsal and anal fins (range 153–169, mode 159), a high count of gill rakers on the first arch (range 35–39, mode 36), and strongly recurved posterior serrae of the pectoral-fin spine. Additionally, results from previously conducted genetic studies corroborate morphologic and taxonomic distinctness of the new species.

  12. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-12-08

    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

  13. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-12-08

    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

  14. Nodosaur Footprint Verified

    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: 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

  15. Nodosaur Footprint Verified

    NASA Image and Video Library

    2012-08-23

    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. Qatar: Energy and development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    El Mallakh, R.

    Despite the traumas that have been experienced in the Arabian Gulf over the past five years, Qatar has been remarkably successful in smoothing the transition of its economy from recession and oil glut to recovery and stabilization. This book examines the characteristics of Qatar's economic and social development that have assisted this process. These characteristics include; moderation in the development policy and the avoidance of excessive haste; a cohesive sense of political identity; and a relatively well educated labor force derived from an educational program that was in place prior to the oil boom. Qatar has also maintained a moderatemore » policy within OPEC. During the price hikes of 1979-80, caused by cutbacks in Iranian exports, Qatar maintained its policy of restraint; this was an important factor in permitting Qatar to confront the substantial drop in oil-generated revenues faced by all the oil exporters in 1982-84.« less

  17. Health Disparities among LGBT Older Adults and the Role of Nonconscious Bias.

    PubMed

    Foglia, Mary Beth; Fredriksen-Goldsen, Karen I

    2014-09-01

    This paper describes the significance of key empirical findings from the recent and landmark study Caring and Aging with Pride: The National Health, Aging and Sexuality Study (with Karen I. Fredriksen-Goldsen as the principal investigator), on lesbian, gay, bisexual, and transgender aging and health disparities. We will illustrate these findings with select quotations from study participants and show how nonconscious bias (i.e., activation of negative stereotypes outside conscious awareness) in the clinical encounter and health care setting can threaten shared decision-making and perpetuate health disparities among LGBT older adults. We recognize that clinical ethicists are not immune from nonconscious bias but maintain that they are well situated to recognize bias and resulting injustice by virtue of their training. Further, we discuss how clinical ethicists can influence the organization's ethical culture and environment to improve the quality and acceptability of health care for LGBT older adults. © 2014 by The Hastings Center.

  18. 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.

  19. Even an old technique is suitable in the molecular world of science: the everted sac preparation turns 60 years old.

    PubMed

    Hamilton, Kirk L

    2014-04-15

    An old proverb states "necessity is the mother of invention." This certainly holds true in science as one pursues research questions. Experimental techniques have evolved as scientists have asked more specific research questions. Indeed, techniques such as the Ussing chamber, the perfused renal tubule preparation, patch-clamp, polymerase chain reaction, and site-directed mutagenesis have been developed over the past 60 years. However, sometimes, simple techniques may be useful and still very informative, and this certainly applies to intestinal physiology. Indeed, Gerald Wiseman and Thomas Hastings Wilson described the intestinal everted sac preparation some 60 years ago. Since then, this technique has been used for numerous research purposes including determining ion, amino acid, water and solute transport across the intestinal epithelium; and drug metabolism, absorption, and interactions in pharmaceutical/pharmacological research and even in education. This article provides a historical review of the development of the in vitro intestinal preparation that led to the everted sac preparation and its use in science.

  20. Seeing responsibility: can neuroimaging teach us anything about moral and legal responsibility?

    PubMed

    Wasserman, David; Johnston, Josephine

    2014-01-01

    As imaging technologies help us understand the structure and function of the brain, providing insight into human capabilities as basic as vision and as complex as memory, and human conditions as impairing as depression and as fraught as psychopathy, some have asked whether they can also help us understand human agency. Specifically, could neuroimaging lead us to reassess the socially significant practice of assigning and taking responsibility? While responsibility itself is not a psychological process open to investigation through neuroimaging, decision-making is. Over the past decade, different researchers and scholars have sought to use neuroimaging (or the results of neuroimaging studies) to investigate what is going on in the brain when we make decisions. The results of this research raise the question whether neuroscience-especially now that it includes neuroimaging-can and should alter our understandings of responsibility and our related practice of holding people responsible. It is this question that we investigate here. © 2014 by The Hastings Center.

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

    PubMed

    Link, William A; Barker, Richard J

    2005-03-01

    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.

  2. 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 relocation1,2,3,4,5,6,7,8,9,10,11,12, species are already being moved to new areas predicted to be more suitable under climate change13,14. 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 management15,16 is valuable when the effect of climate change on source habitat is uncertain, and leads to delayed movement.

  3. 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.

  4. Coercivity enhancement of sintered Nd-Fe-B magnets by chemical bath deposition of TbCl{sub 3}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guo, Shuai, E-mail: gshuai@nimte.ac.cn; Zhang, Xiaofeng; Ding, Guangfei

    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 themore » 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.« less

  5. 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.

  6. Comparative Reliability Studies and Analysis of Au, Pd-Coated Cu and Pd-Doped Cu Wire in Microelectronics Packaging

    PubMed Central

    Chong Leong, Gan; Uda, Hashim

    2013-01-01

    This paper compares and discusses the wearout reliability and analysis of Gold (Au), Palladium (Pd) coated Cu and Pd-doped Cu wires used in fineline Ball Grid Array (BGA) package. Intermetallic compound (IMC) thickness measurement has been carried out to estimate the coefficient of diffusion (Do) under various aging conditions of different bonding wires. Wire pull and ball bond shear strengths have been analyzed and we found smaller variation in Pd-doped Cu wire compared to Au and Pd-doped Cu wire. Au bonds were identified to have faster IMC formation, compared to slower IMC growth of Cu. The obtained weibull slope, β of three bonding wires are greater than 1.0 and belong to wearout reliability data point. Pd-doped Cu wire exhibits larger time-to-failure and cycles-to-failure in both wearout reliability tests in Highly Accelerated Temperature and Humidity (HAST) and Temperature Cycling (TC) tests. This proves Pd-doped Cu wire has a greater potential and higher reliability margin compared to Au and Pd-coated Cu wires. PMID:24244344

  7. Adaptation of a 3-D Quadrupole Ion Trap for Dipolar DC Collisional Activation

    PubMed Central

    Prentice, Boone M.; Santini, Robert E.; McLuckey, Scott A.

    2011-01-01

    Means to allow for the application of a dipolar DC pulse to the end-cap electrodes of a three-dimensional (3-D) quadrupole ion trap for as short as a millisecond to as long as hundreds of milliseconds are described. The implementation of dipolar DC does not compromise the ability to apply AC waveforms to the end-cap electrodes at other times in the experiment. Dipolar DC provides a nonresonant means for ion acceleration by displacing ions from the center of the ion trap where they experience stronger rf electric fields, which increases the extent of micro-motion. The evolution of the product ion spectrum to higher generation products with time, as shown using protonated leucine enkephalin as a model protonated peptide, illustrates the broad-band nature of the activation. Dipolar DC activation is also shown to be effective as an ion heating approach in mimicking high amplitude short time excitation (HASTE)/pulsed Q dissociation (PQD) resonance excitation experiments that are intended to enhance the likelihood for observing low m/z products in ion trap tandem mass spectrometry. PMID:21953251

  8. Quarantine Controversy: Kaci Hickox v. Governor Chris Christie.

    PubMed

    Gatter, Robert

    2016-05-01

    Nurse Kaci Hickox is among the "Ebola Fighters" honored by Time magazine as its 2014 Person of the Year, having treated Ebola patients in Sierra Leone while volunteering with Médecins Sans Frontieres. When she returned to the United States in October 2014, she was quarantined in New Jersey for three days before returning home to Maine under the terms of a negotiated release. A year later, in October 2015, Hickox filed suit in federal court against Governor Chris Christie and New Jersey health officials, claiming that the quarantine violated her civil rights. Her complaint asserts that New Jersey officials lacked the authority to quarantine her because she did not pose a significant risk of transmission. The lawsuit raises important questions about disease-transmission risk, the inability of science to rule out certain theoretical risks, and the state's power to quarantine. It also demonstrates that population health depends on respecting individual liberty and using the best available epidemiological data to set public health policy. © 2016 The Hastings Center.

  9. Taking a Stand: The Genetics Community's Responsibility for Intelligence Research.

    PubMed

    Callier, Shawneequa L; Bonham, Vence L

    2015-01-01

    There is a longstanding debate about genetics research into intelligence. Some scholars question the value of focusing on genetic contributions to intelligence in a society where social and environmental determinants powerfully influence cognitive ability and educational outcomes. Others warn that censoring certain research questions, such as inquiries about genetic differences in intellectual potential, compromises academic freedom. Still others view interest in this subject as a corollary to a long and troublesome history of eugenics research. The dawn of a new era in genome sequencing as a commodity will sustain scientific interest in the genetics of intelligence for the foreseeable future, but deep-rooted challenges threaten the scientific merit of the research. The use of imprecise definitions of study populations, the difficult nature of studying the environment, and the potential of researcher bias are inextricably linked with concerns about the trustworthiness and utility of research in this area. Leadership by the genetics community is essential to ensure the value and trustworthiness of these studies. © 2015 The Hastings Center.

  10. Rapid Non-Gaussian Uncertainty Quantification of Seismic Velocity Models and Images

    NASA Astrophysics Data System (ADS)

    Ely, G.; Malcolm, A. E.; Poliannikov, O. V.

    2017-12-01

    Conventional seismic imaging typically provides a single estimate of the subsurface without any error bounds. Noise in the observed raw traces as well as the uncertainty of the velocity model directly impact the uncertainty of the final seismic image and its resulting interpretation. We present a Bayesian inference framework to quantify uncertainty in both the velocity model and seismic images, given noise statistics of the observed data.To estimate velocity model uncertainty, we combine the field expansion method, a fast frequency domain wave equation solver, with the adaptive Metropolis-Hastings algorithm. The speed of the field expansion method and its reduced parameterization allows us to perform the tens or hundreds of thousands of forward solves needed for non-parametric posterior estimations. We then migrate the observed data with the distribution of velocity models to generate uncertainty estimates of the resulting subsurface image. This procedure allows us to create both qualitative descriptions of seismic image uncertainty and put error bounds on quantities of interest such as the dip angle of a subduction slab or thickness of a stratigraphic layer.

  11. Exact posterior computation in non-conjugate Gaussian location-scale parameters models

    NASA Astrophysics Data System (ADS)

    Andrade, J. A. A.; Rathie, P. N.

    2017-12-01

    In Bayesian analysis the class of conjugate models allows to obtain exact posterior distributions, however this class quite restrictive in the sense that it involves only a few distributions. In fact, most of the practical applications involves non-conjugate models, thus approximate methods, such as the MCMC algorithms, are required. Although these methods can deal with quite complex structures, some practical problems can make their applications quite time demanding, for example, when we use heavy-tailed distributions, convergence may be difficult, also the Metropolis-Hastings algorithm can become very slow, in addition to the extra work inevitably required on choosing efficient candidate generator distributions. In this work, we draw attention to the special functions as a tools for Bayesian computation, we propose an alternative method for obtaining the posterior distribution in Gaussian non-conjugate models in an exact form. We use complex integration methods based on the H-function in order to obtain the posterior distribution and some of its posterior quantities in an explicit computable form. Two examples are provided in order to illustrate the theory.

  12. Nodosaur Footprint Verified

    NASA Image and Video Library

    2017-12-08

    On Friday, Aug. 17, 2012, noted dinosaur hunter Ray Stanford shared the location of that footprint with Goddard’s facility management. 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. Picuted here are Dr. Robert Weems, emeritus paleontologist for the USGS and Goddard Facilities Planner Alan Binstock, covering the newly discover nodosaur imprint with a sandbag to help preserve the imprecision. 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

  13. [MR cholangiopancreatography in choledochal cysts].

    PubMed

    Frampas, E; Moussaly, F; Léauté, F; Heloury, Y; Le Neel, J C; Dupas, B

    1999-12-01

    To assess the value of MR cholangiopancreatography (MRCP) in the diagnosis and preoperative evaluation of choledochal cysts. Five patients (aged between 6 days and 28 years) were investigated by MRCP, referred for ultrasonographic detection of a bile duct dilatation or a cystic structure, of antenatal diagnosis (1 case), for jaundice or abdominal pain (3 cases) or in late follow-up of a choledochal cyst surgery. Two endoscopic-ultrasonographic studies were performed. The five patients underwent surgery without preoperative biliary cholangiography. MRCP was performed using a HASTE sequence in frontal, oblique, axial planes (1,5 Tesla MR unit). MRCP allowed to confirm choledochal cyst, helps to specify the anatomical type (2 type I, 3 type II), detects choledocholithiasis (3 cases). Anatomic correlation was perfect. MRCP allowed to exclude gastrointestinal duplication. Anomalous junction of the pancreaticobiliary duct was found in one case. MRCP diagnoses choledochal cysts, specifies type, helps surgery and can avoid endoscopic retrograde cholangiography or endoscopic sonographic examinations especially for children. It may find an anomalous junction of the pancreaticobiliary duct.

  14. Model selection and Bayesian inference for high-resolution seabed reflection inversion.

    PubMed

    Dettmer, Jan; Dosso, Stan E; Holland, Charles W

    2009-02-01

    This paper applies Bayesian inference, including model selection and posterior parameter inference, to inversion of seabed reflection data to resolve sediment structure at a spatial scale below the pulse length of the acoustic source. A practical approach to model selection is used, employing the Bayesian information criterion to decide on the number of sediment layers needed to sufficiently fit the data while satisfying parsimony to avoid overparametrization. Posterior parameter inference is carried out using an efficient Metropolis-Hastings algorithm for high-dimensional models, and results are presented as marginal-probability depth distributions for sound velocity, density, and attenuation. The approach is applied to plane-wave reflection-coefficient inversion of single-bounce data collected on the Malta Plateau, Mediterranean Sea, which indicate complex fine structure close to the water-sediment interface. This fine structure is resolved in the geoacoustic inversion results in terms of four layers within the upper meter of sediments. The inversion results are in good agreement with parameter estimates from a gravity core taken at the experiment site.

  15. New Zealand’s deadliest quake sounds alarm for cities on fault lines

    USGS Publications Warehouse

    Kalkan, Erol

    2012-01-01

    The catastrophic Christ Church Earthquake is a strong reminder to engineers and scientists of the hazards pose by fault lines, both mapped and unknown, near major cities. In February 2011, the relatively moderate earthquake that struck the cities of Christchurch and Lyttleton in the Canterbury region of New Zealand's South Island surprised many with its destructive power. The magnitude 6.2 temblor killed 181 people, 118 of whom were killed in the collapse of a single building in the city center. The quake damaged or destroyed more than 100,000 buildings.It was the deadliest quake to strike the nation in 80 years-since the 1931 earthquake that struck the Napier and Hastings area of the North Island. The Christchurch quake was part of the aftershock sequence following the September 2010 magnitude 7.1 earthquake near Darfield, 40 kilometers west of the city. The Darfield earthquake was in a sparsely populated area, causing to loss of life. By contrast, the Christchurch earthquake was generated on a fault in close proximity to the city.

  16. Chemical analyses of surface waters in Oklahoma, September - December, 1944

    USGS Publications Warehouse

    ,

    1945-01-01

    Red River at Denison Dam, Texas Sport samples were collected at the remainder of the stations. The analyses of the spot samples were made largely in a laboratory provided by the Oklahoma A. & M. College, under the supervision of Dr. O.M. Smith, Head, Department of Chemistry; Dr. S.R. Wood, Associate Professor of Chemistry; and W.W. Hastings, U.S. Geological Survey. The daily samples were analyzed in the water resources laboratory of the Geological Survey at Austin, Texas. These data have been summarized in a report to the Oklahoma Planning and Resources Board prepared by the U.S. Geological Survey, March 1, 1945. The streams of Oklahoma are classified into two major drainage basins: the Arkansas River and the Red River and their tributaries. The attached analyses are arranged in geographical order for their respective drainage basins, with records listed in downstream order for stations on the main stem first, followed by the analyses for the tributaries. When available, the mean daily discharge is given for the analyses.

  17. 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

  18. The Pedagogical Challenges of Teaching High School Bioethics: Insights from the Exploring Bioethics Curriculum.

    PubMed

    Solomon, Mildred Z; Vannier, David; Chowning, Jeanne Ting; Miller, Jacqueline S; Paget, Katherine F

    2016-01-01

    A belief that high school students have the cognitive ability to analyze and assess moral choices and should be encouraged to do so but have rarely been helped to do so was the motivation for developing Exploring Bioethics, a six-module curriculum and teacher guide for grades nine through twelve on ethical issues in the life sciences. A multidisciplinary team of bioethicists, science educators, curriculum designers, scientists, and high school biology teachers worked together on the curriculum under a contract between the National Institutes of Health and Education Development Center, a nonprofit research and development organization with a long history of innovation in science education. At the NIH, the Department of Bioethics within the Clinical Center and the Office of Science Education within the Office of the Director guided the project.Our overarching goal for Exploring Bioethics was to introduce students to bioethics as a field of inquiry and to enable them to develop ethical reasoning skills so they could move beyond "gut reactions" to more nuanced positions. © 2016 The Hastings Center.

  19. Local perturbations perturb—exponentially-locally

    NASA Astrophysics Data System (ADS)

    De Roeck, W.; Schütz, M.

    2015-06-01

    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.

  20. 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.

  1. General Intelligence (g): Overview of a Complex Construct and Its Implications for Genetics Research.

    PubMed

    Plucker, Jonathan A; Shelton, Amy L

    2015-01-01

    Current technology has dramatically increased the prevalence of studies to establish the genetic correlates of a wide variety of human characteristics, including not only the physical attributes that determine what we look like and the risk of physiological disease but also the psychological and cognitive characteristics that often define who we are as individuals. Perhaps one of the most deeply personal and often controversial characteristics is the concept of general intelligence, known in the psychological literature as "g." As with the genetic study of any complex trait, the first step in studying the genetics of g is to carefully define the characteristic of interest. For g, this entails establishing what intelligence means and providing a clear operational definition for how it will be measured. In this paper, we provide a brief historical and theoretical overview of the construct of general intelligence, describe its relationship to the contemporary measurement of intelligence, and discuss these concepts in light of the challenges associated with defining g as a characteristic in the study of genetics. © 2015 The Hastings Center.

  2. Markov Chain Monte Carlo in the Analysis of Single-Molecule Experimental Data

    NASA Astrophysics Data System (ADS)

    Kou, S. C.; Xie, X. Sunney; Liu, Jun S.

    2003-11-01

    This article provides a Bayesian analysis of the single-molecule fluorescence lifetime experiment designed to probe the conformational dynamics of a single DNA hairpin molecule. The DNA hairpin's conformational change is initially modeled as a two-state Markov chain, which is not observable and has to be indirectly inferred. The Brownian diffusion of the single molecule, in addition to the hidden Markov structure, further complicates the matter. We show that the analytical form of the likelihood function can be obtained in the simplest case and a Metropolis-Hastings algorithm can be designed to sample from the posterior distribution of the parameters of interest and to compute desired estiamtes. To cope with the molecular diffusion process and the potentially oscillating energy barrier between the two states of the DNA hairpin, we introduce a data augmentation technique to handle both the Brownian diffusion and the hidden Ornstein-Uhlenbeck process associated with the fluctuating energy barrier, and design a more sophisticated Metropolis-type algorithm. Our method not only increases the estimating resolution by several folds but also proves to be successful for model discrimination.

  3. A bayesian hierarchical model for classification with selection of functional predictors.

    PubMed

    Zhu, Hongxiao; Vannucci, Marina; Cox, Dennis D

    2010-06-01

    In functional data classification, functional observations are often contaminated by various systematic effects, such as random batch effects caused by device artifacts, or fixed effects caused by sample-related factors. These effects may lead to classification bias and thus should not be neglected. Another issue of concern is the selection of functions when predictors consist of multiple functions, some of which may be redundant. The above issues arise in a real data application where we use fluorescence spectroscopy to detect cervical precancer. In this article, we propose a Bayesian hierarchical model that takes into account random batch effects and selects effective functions among multiple functional predictors. Fixed effects or predictors in nonfunctional form are also included in the model. The dimension of the functional data is reduced through orthonormal basis expansion or functional principal components. For posterior sampling, we use a hybrid Metropolis-Hastings/Gibbs sampler, which suffers slow mixing. An evolutionary Monte Carlo algorithm is applied to improve the mixing. Simulation and real data application show that the proposed model provides accurate selection of functional predictors as well as good classification.

  4. The Time Is Now: Bioethics and LGBT Issues.

    PubMed

    Powell, Tia; Foglia, Mary Beth

    2014-09-01

    Our goal in producing this special issue is to encourage our colleagues to incorporate topics related to LGBT populations into bioethics curricula and scholarship. Bioethics has only rarely examined the ways in which law and medicine have defined, regulated, and often oppressed sexual minorities. This is an error on the part of bioethics. Medicine and law have served in the past as society's enforcement arm toward sexual minorities, in ways that robbed many people of their dignity. We feel that bioethics has an obligation to discuss that history and to help us as a society take responsibility for it. We can address only a small number of topics in this special issue of the Hastings Center Report, and we selected topics we believe will stimulate discourse. Andrew Solomon offers an elegant overview of the challenges that bioethics faces in articulating a solid basis for LGBT rights. Timothy F. Murphy asks whether bioethics still faces issues related to lesbian, gay, and bisexual people, given the deletion of homosexuality as a disease and the progress toward same-sex marriage. Jamie Lindemann Nelson's essay addresses the search for identity for transgender persons and the role of science in that search. Two articles, those by Brendan S. Abel and by Jack Drescher and Jack Pula, take up the complex issue of medical treatment for children who reject their assigned birth gender. Celia B. Fisher and Brian Mustanski address the special challenges of engaging LGBT youth in research, balancing the need for better information about this vulnerable group against the existing restrictions on research involving children. Tia Powell and Edward Stein consider the merits of legal bans on psychotherapies intended to change sexual orientation, particularly in the light of current research on orientation. Mary Beth Foglia and Karen I. Fredricksen-Goldsen highlight health disparities and resilience among LGBT older adults and then discuss the role of nonconscious bias in perpetuating

  5. Virtual goods recommendations in virtual worlds.

    PubMed

    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.

  6. A continuous-wave ultrasound system for displacement amplitude and phase measurement.

    PubMed

    Finneran, James J; Hastings, Mardi C

    2004-06-01

    A noninvasive, continuous-wave ultrasonic technique was developed to measure the displacement amplitude and phase of mechanical structures. The measurement system was based on a method developed by Rogers and Hastings ["Noninvasive vibration measurement system and method for measuring amplitude of vibration of tissue in an object being investigated," U.S. Patent No. 4,819,643 (1989)] and expanded to include phase measurement. A low-frequency sound source was used to generate harmonic vibrations in a target of interest. The target was simultaneously insonified by a low-power, continuous-wave ultrasonic source. Reflected ultrasound was phase modulated by the target motion and detected with a separate ultrasonic transducer. The target displacement amplitude was obtained directly from the received ultrasound frequency spectrum by comparing the carrier and sideband amplitudes. Phase information was obtained by demodulating the received signal using a double-balanced mixer and low-pass filter. A theoretical model for the ultrasonic receiver field is also presented. This model coupled existing models for focused piston radiators and for pulse-echo ultrasonic fields. Experimental measurements of the resulting receiver fields compared favorably with theoretical predictions.

  7. Trump's Abortion-Promoting Aid Policy.

    PubMed

    Latham, Stephen R

    2017-07-01

    On the fourth day of his presidency, Donald Trump reinstated and greatly expanded the "Mexico City policy," which imposes antiabortion restrictions on U.S. foreign health aid. In general, the policy has prohibited U.S. funding of any family-planning groups that use even non-U.S. funds to perform abortions; prohibited aid recipients from lobbying (again, even with non-U.S. money) for liberalization of abortion laws; prohibited nongovernment organizations from creating educational materials on abortion as a family-planning method; and prohibited health workers from referring patients for legal abortions in any cases other than rape, incest, or to save the life of the mother. The policy's prohibition on giving aid to any organization that performs abortions is aimed at limiting alleged indirect funding of abortions. The argument is that if U.S. money is used to fund nonabortion programs of an abortion-providing NGO, then the NGO can simply shift the money thus saved into its abortion budget. Outside the context of abortion, we do not reason this way. And the policy's remaining three prohibitions are deeply troubling. © 2017 The Hastings Center.

  8. Legal and Ethical Concerns about Sexual Orientation Change Efforts.

    PubMed

    Powell, Tia; Stein, Edward

    2014-09-01

    The United States has recently made significant and positive civil rights gains for LGB people, including expanded recognition of marriages between people of the same sex. Among the central tropes that have emerged in the struggle for the rights of LGB people are that they are "born that way," that sexual orientations cannot change, and that one's sexual orientation is not affected by choice. Writer Andrew Sullivan put it this way: "[H]omosexuality is an essentially involuntary condition that can neither be denied nor permanently repressed.… [S]o long as homosexual adults as citizens insist on the involuntary nature of their condition, it becomes politically impossible to deny or ignore the fact of homosexuality.… [The strategy for obtaining LGB rights is to] seek full public equality for those who, through no fault of their own, happen to be homosexual." This idea of linking LGB rights to empirical claims about sexual orientations has become so central that casting doubt on these claims is, in many circles, tantamount to opposing LGB rights. Nonetheless, claims about innateness, immutability, and lack of choice about sexual orientation should not be the primary basis for LGB rights. © 2014 by The Hastings Center.

  9. Learn-as-you-go acceleration of cosmological parameter estimates

    NASA Astrophysics Data System (ADS)

    Aslanyan, Grigor; Easther, Richard; Price, Layne C.

    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.

  10. Effective gravitational coupling in modified teleparallel theories

    NASA Astrophysics Data System (ADS)

    Abedi, Habib; Capozziello, Salvatore; D'Agostino, Rocco; Luongo, Orlando

    2018-04-01

    In the present study, we consider an extended form of teleparallel Lagrangian f (T ,ϕ ,X ) , as function of a scalar field ϕ , its kinetic term X and the torsion scalar T . We use linear perturbations to obtain the equation of matter density perturbations on sub-Hubble scales. The gravitational coupling is modified in scalar modes with respect to the one of general relativity, albeit vector modes decay and do not show any significant effects. We thus extend these results by involving multiple scalar field models. Further, we study conformal transformations in teleparallel gravity and we obtain the coupling as the scalar field is nonminimally coupled to both torsion and boundary terms. Finally, we propose the specific model f (T ,ϕ ,X )=T +∂μϕ ∂μϕ +ξ T ϕ2 . To check its goodness, we employ the observational Hubble data, constraining the coupling constant, ξ , through a Monte Carlo technique based on the Metropolis-Hastings algorithm. Hence, fixing ξ to its best-fit value got from our numerical analysis, we calculate the growth rate of matter perturbations and we compare our outcomes with the latest measurements and the predictions of the Λ CDM model.

  11. Crowdsourcing the Moral Limits of Human Gene Editing?

    PubMed

    Juengst, Eric T

    2017-05-01

    In 2015, a flourish of "alarums and excursions" by the scientific community propelled CRISPR/Cas9 and other new gene-editing techniques into public attention. At issue were two kinds of potential gene-editing experiments in humans: those making inheritable germ-line modifications and those designed to enhance human traits beyond what is necessary for health and healing. The scientific consensus seemed to be that while research to develop safe and effective human gene editing should continue, society's moral uncertainties about these two kinds of experiments needed to be better resolved before clinical trials of either type should be attempted. In the United States, the National Academies of Science, Engineering and Medicine (NASEM) convened the Committee on Human Gene Editing: Scientific, Medical and Ethical Considerations to pursue that resolution. 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. There are two reasons for this eccentric conclusion, both of which depend upon the strength of the committee's commitment to engaging diverse public voices in the gene-editing policy-making process. © 2017 The Hastings Center.

  12. 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.

  13. [Accessibility and resolution of mental health care: the matrix support experience].

    PubMed

    Quinderé, Paulo Henrique Dias; Jorge, Maria Salete Bessa; Nogueira, Maria Sônia Lima; Costa, Liduina Farias Almeida da; Vasconcelos, Mardenia Gomes Ferreira

    2013-07-01

    Psycho-social Care Centers (PCC) are also designed to coordinate actions in mental health care in Brazil, mainly at Primary Health Care (PHC) level. Matrix support is one of the pillars of the program, as it aims to ensure assistance of specialized back-up staff to the health teams. In this respect, this research seeks to understand how matrix actions in mental health contribute to the accessibility and resolution of mental health cases. This study involved qualitative research conducted in the cities of Fortaleza and Sobral in the State of Ceará, where 37 (thirty-seven) mental health workers, 14 (fourteen) primary health care users and 13 (thirteen) relatives who took part in matrix support actions were interviewed. As the results revealed, the PHC workers do not feel qualified to intervene in mental health cases. There is also excess haste in referring users to PCCs making access to mental health care more difficult. However, it was identified that discussions on mental health in primary care allow the appropriation of cases by PHC workers and promote rapprochement between the teams. In this way, they influence the resolution of mental health cases.

  14. Market Language, Moral Language.

    PubMed

    Goold, Susan Dorr

    2018-01-01

    Those who advocate higher out-of-pocket spending, especially high deductibles, to keep health care costs better controlled without losing quality use market language to talk about how people should think about health care. Consumers-that is, patients-should hunt for bargains. Clip coupons. Shop around. Patients need to have more "skin in the game." Consumer-patients will then choose more carefully and prudently and use less unnecessary health care. Unfailingly, "skin" refers to having money at stake. Usually, those arguing for high deductibles express dismay or frustration that patients do not face the full ("true") cost of the health services they receive. Unfortunately, a lack of price transparency, the need to unbundle bundled groups of services to discover total price, and the challenge of validly and reliably measuring and disclosing quality make shopping for health care a challenge for even the savviest patient. Urgency, fear, and sickness that impairs peak cognitive function and other aspects of emotionally laden decision-making, even when "shared" with a physician, add obstacles to coupon clipping and tire kicking. Who has more at stake in health decisions than patients? Whose flesh is literally, not just figuratively, at risk? © 2018 The Hastings Center.

  15. 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.

  16. 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.

  17. Flow and chloride transport in the tidal Hudson River, NY

    USGS Publications Warehouse

    Weiss, Lawrence A.; Schaffranek, Raymond W.; de Vries, M. Peter

    1994-01-01

    A one-dimensional dynamic-flow model and a one-dimensional solute-transport model were used to evaluate the effects of hypothetical public-supply water withdrawals on saltwater intrusion in a 133-mile reach of the tidal Hudson River between Green Island dam, near Troy, N.Y., and Hastings-on-Hudson, N.Y. Regression techniques were used in analyses of current and extreme historical conditions, and numerical models were used to investigate the effect of various water withdrawals. Of four withdrawal scenarios investigated, simulations of a 27-day period during which discharges at Green Island dam averaged 7,090 ft3/s indicate that increasing the present Chelsea pumping-station withdrawal rate of 100 Mgal/d (million gallons per day) to 300 Mgal/d would have the least effect on upstream saltwater movement. A 90-day simulation, during which discharges at Green Island dam averaged 25,200 ft3/s, indicates that withdrawals of 1,940 Mgal/d at Chelsea would not measurably increase chloride concentrations at Chelsea under normal tidal and meteorological conditions, but withdrawals of twice that rate (3,880 Mgal/d) could increase the chloride concentration at Chelsea to 250 mg/L.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crowder, Jeff; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109; Cornish, Neil J.

    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 presentmore » 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.« less

  19. Practitioner attitudes in the United States and United Kingdom toward decisions at the end of life

    PubMed Central

    Dickenson, Donna L

    2001-01-01

    Objective To assess whether UK and US health care professionals share the views of medical ethicists about medical futility, withdrawing or withholding treatment, ordinary or extraordinary interventions, and the doctrine of double effect. Design, subjects, and setting Answers to a 138-item attitudinal questionnaire completed by 469 UK nurses studying the Open University course on “Death and Dying” were compared with those of a similar questionnaire administered to 759 US nurses and 687 US physicians taking the Hastings Center course on “Decisions Near the End of Life.” Results Practitioners accept the relevance of concepts widely disparaged by bioethicists: double effect, medical futility, and the distinctions between heroic and ordinary interventions and withholding and withdrawing treatment. Within the UK nurses' group, the responses of a “rationalist” axis of respondents who describe themselves as having “no religion” are closer to the bioethics consensus on withholding and withdrawing treatment. Conclusions Professionals' beliefs differ substantially from the recommendations of their professional bodies and from majority opinion in bioethics. Bioethicists should be cautious about assuming that their opinions will be readily accepted by practitioners.

  20. Physician-Assisted Death and Severe, Treatment-Resistant Depression.

    PubMed

    Steinbock, Bonnie

    2017-09-01

    Should people suffering from untreatable psychiatric conditions be eligible for physician-assisted death? This is possible in Belgium and the Netherlands, where PAD for psychiatric conditions is permitted, though rare, so long as the criteria of due care are met. Those opposed to all instances of PAD point to Belgium and the Netherlands as a dark warning that once PAD is legalized, restricting it will prove impossible because safeguards, such as the requirement that a patient be terminally ill, will inevitably be eroded or discarded. However, some supporters respond that limiting PAD to those suffering from terminal illness, or physical illnesses generally, is arbitrary and illogical. In addition, precisely because such patients are not terminally ill, their suffering may last for years, even the rest of their lives. Finally, severe depression may not be treatable. If PAD is justifiable under some conditions-as I shall assume in this article-then why wouldn't it be justifiable for these patients? Why shouldn't psychiatrists who have nothing else to offer their suffering patients be able to help them to die, if that is what they want? © 2017 The Hastings Center.

  1. Enhancing moral agency: clinical ethics residency for nurses.

    PubMed

    Robinson, Ellen M; Lee, Susan M; Zollfrank, Angelika; Jurchak, Martha; Frost, Debra; Grace, Pamela

    2014-09-01

    One antidote to moral distress is stronger moral agency-that is, an enhanced ability to act to bring about change. The Clinical Ethics Residency for Nurses, an educational program developed and run in two large northeastern academic medical centers with funding from the Health Resources and Services Administration, intended to strengthen nurses' moral agency. Drawing on Improving Competencies in Clinical Ethics Consultation: An Education Guide, by the American Society for Bioethics and Humanities, and on the goals of the nursing profession, CERN sought to change attitudes, increase knowledge, and develop skills to act on one's knowledge. One of the key insights the faculty members brought to the design of this program is that knowledge of clinical ethics is not enough to develop moral agency. In addition to lecture-style classes, CERN employed a variety of methods based in adult learning theory, such as active application of ethics knowledge to patient scenarios in classroom discussion, simulation, and the clinical practicum. Overwhelmingly, the feedback from the participants (sixty-seven over three years of the program) indicated that CERN achieved transformative learning. © 2014 by The Hastings Center.

  2. 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

  3. 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

  4. Space for the Prisoner's Point of View.

    PubMed

    Haupt, Laura

    2017-03-01

    The lead article in this issue discusses a potentially free metaphorical space-that of decision-making-within the confines, tangible and intangible, of life in jail or prison. By interviewing prisoner-participants from six clinical studies, Paul Christopher and colleagues sought to find out how these men and women would answer open-ended questions about their decision to enroll in the research. What the interviewers heard was that none saw themselves as having been inappropriately pressured to do so. In fact, a significant percentage of the prisoners described being dissuaded from participating in the studies. The authors therefore advise that unfair exploitation poses the more relevant research risk to contemporary prisoners in the United States than does coercion, and they encourage investigations into whether prisoners are unfairly restricted or discouraged from joining clinical studies. Although Keramet Reiter makes no reference to etymology in her commentary responding to the article, her argument suggests that the roots of "coerce"-the Latin for "shut up" or "enclose"-remain relevant. Reiter argues that, under current conditions, the people shut up in prisons in the United States cannot make an unfettered choice to join a clinical trial. © 2017 The Hastings Center.

  5. Ethical and equity issues in lung transplantation and lung volume reduction surgery.

    PubMed

    Glanville, A R

    2006-01-01

    New medical and scientific disciplines are often developed in haste with rampant enthusiasm and scant regard for the balance between action and thoughtful deliberation. Driven by the desire to prolong life and provide a better quality of life for desperately sick individuals, the twin modalities of lung transplantation and lung volume reduction therapy have only just reached their majority. Both are invested with the capacity to help and to harm so it is right to consider carefully their ethical and equitable distribution. Much has been learned in the last 20 years to assist in these deliberations. First, how can we ensure equity of access to transplant services and equality of outcomes? How do we balance resource allocation of a precious and scarce resource with individual recipient needs? Does the concept of distributive justice prevail in our daily work in this field? How do we honour the donor and their family? How do we as practitioners avoid ethical dilemmas related to personal bias and justifiable reward for services rendered? Finally, how do we learn to incorporate ethical forethought and planning guided by experts in the area into everyday behaviour?

  6. 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.

  7. Nursing's Code of Ethics, Social Ethics, and Social Policy.

    PubMed

    Fowler, Marsha D

    2016-09-01

    Modern American nursing arose during the Civil War and subsequently adopted the Nightingale educational model in the 1870s. By 1889, the journal Trained Nurse and Hospital Review had been established. It published a six-part series on ethics in nursing. With the establishment of the American Nurses Association in 1893, the articles of incorporation gave the organization its first charge: "to establish and maintain a code of ethics." While the rich and enduring tradition of nursing's ethics has been concerned about individual patients and their relational nexus, nursing ethics has from the beginning been a social ethics, intimately concerned both for the shape of society and for social change. This concern has been for health, conceived broadly and not focused specifically on disease and its treatment, but including the social causes of disease. Nightingale herself was an ardent social reformer, instituting a wide range of types of army sanitation reform, sanitation reform in India, and hospital and nursing reform. Despite her gender, her wealth and privilege granted her access to men in power who furthered her policy and reform agenda. From the start, then, modern nursing was imbued with a social reformist bias. © 2016 The Hastings Center.

  8. A brief introduction to computer-intensive methods, with a view towards applications in spatial statistics and stereology.

    PubMed

    Mattfeldt, Torsten

    2011-04-01

    Computer-intensive methods may be defined as data analytical procedures involving a huge number of highly repetitive computations. We mention resampling methods with replacement (bootstrap methods), resampling methods without replacement (randomization tests) and simulation methods. The resampling methods are based on simple and robust principles and are largely free from distributional assumptions. Bootstrap methods may be used to compute confidence intervals for a scalar model parameter and for summary statistics from replicated planar point patterns, and for significance tests. For some simple models of planar point processes, point patterns can be simulated by elementary Monte Carlo methods. The simulation of models with more complex interaction properties usually requires more advanced computing methods. In this context, we mention simulation of Gibbs processes with Markov chain Monte Carlo methods using the Metropolis-Hastings algorithm. An alternative to simulations on the basis of a parametric model consists of stochastic reconstruction methods. The basic ideas behind the methods are briefly reviewed and illustrated by simple worked examples in order to encourage novices in the field to use computer-intensive methods. © 2010 The Authors Journal of Microscopy © 2010 Royal Microscopical Society.

  9. Advanced bridge safety initiative : live load testing and load rating of the Evans Brook Bridge (#5506) and the Hastings Bridge (#5507) in Batchelders Grant, Maine.

    DOT National Transportation Integrated Search

    2014-01-01

    The Advanced Structures and Composites Center at the University of Maine (UMaine) performed live load testing : and rating factor analysis for two bridges (No. 5506 and No. 5507) in Batchelders Grant, Maine. The bridge load : rating performed by cons...

  10. Itô-SDE MCMC method for Bayesian characterization of errors associated with data limitations in stochastic expansion methods for uncertainty quantification

    NASA Astrophysics Data System (ADS)

    Arnst, M.; Abello Álvarez, B.; Ponthot, J.-P.; Boman, R.

    2017-11-01

    This paper is concerned with the characterization and the propagation of errors associated with data limitations in polynomial-chaos-based stochastic methods for uncertainty quantification. Such an issue can arise in uncertainty quantification when only a limited amount of data is available. When the available information does not suffice to accurately determine the probability distributions that must be assigned to the uncertain variables, the Bayesian method for assigning these probability distributions becomes attractive because it allows the stochastic model to account explicitly for insufficiency of the available information. In previous work, such applications of the Bayesian method had already been implemented by using the Metropolis-Hastings and Gibbs Markov Chain Monte Carlo (MCMC) methods. In this paper, we present an alternative implementation, which uses an alternative MCMC method built around an Itô stochastic differential equation (SDE) that is ergodic for the Bayesian posterior. We draw together from the mathematics literature a number of formal properties of this Itô SDE that lend support to its use in the implementation of the Bayesian method, and we describe its discretization, including the choice of the free parameters, by using the implicit Euler method. We demonstrate the proposed methodology on a problem of uncertainty quantification in a complex nonlinear engineering application relevant to metal forming.

  11. 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.

  12. Medical triage for WMD incidents incidents: an adaptation of daily triage.

    PubMed

    Donohue, Dave

    2008-05-01

    It's 2000 HRS on a Friday evening. You're assigned to an ALS engine company, and you're just settling down after a busy day when you're dispatched along with a BLS ambulance to a report of a sick person outside a local club where they're holding a concert. During your response, dispatch advises that they're receiving multiple calls on the incident and are dispatching a second BLS ambulance to the call. * As you turn the corner and approach the scene, you notice a haze in the air coming from an industrial site on the same side of the street and see approximately 200 people exiting the club in haste. Several dozen patrons line the street between the club and the subway station. They're coughing and crying, and several are vomiting. * The driver stops the engine in front of the subway entrance, which is located approximately 500 feet from the club and uphill and upwind from the haze. The scene is overwhelming, even to the captain, who turns to you-as the paramedic on the crew-and asks what you want done first. Your first thought is, Triage. But you know that triaging these patients is more complicated than your everyday two-car collision.

  13. How Long a Life Is Enough Life?

    PubMed

    Callahan, Daniel; Gaylin, Willard

    2017-07-01

    Humans have long been troubled by the prospect of old age and its culmination in death. Whether to rebel against or accept this fate have been wrestled with down through the centuries. But new medical technologies and the growing science of aging have sided with rebellion. We know that aging can be pushed back and improved in its quality. That progress is well under way, but now intensified by many scientists and Silicon Valley entrepreneurs. In 2016, Mark Zuckerberg and Priscilla Chan pledged three billion dollars toward eventually "preventing, curing or managing all diseases." And some visionaries have made the elimination of death or its indefinite postponement a goal. To put those aspirations in a broader context, it is helpful to keep in mind where population growth and aging trends stand. Apart from any success in the explicit efforts to increase longevity, there will be a steady increase in the number of elderly worldwide-and a much higher percentage of the elderly as part of the overall population. Most of the largest changes will be in developing countries. They will be overburdened by the death of the elderly from expensive chronic diseases-already a vexing problem for affluent countries. © 2017 The Hastings Center.

  14. A comparison of Monte Carlo-based Bayesian parameter estimation methods for stochastic models of genetic networks

    PubMed Central

    Zaikin, Alexey; Míguez, Joaquín

    2017-01-01

    We compare three state-of-the-art Bayesian inference methods for the estimation of the unknown parameters in a stochastic model of a genetic network. In particular, we introduce a stochastic version of the paradigmatic synthetic multicellular clock model proposed by Ullner et al., 2007. By introducing dynamical noise in the model and assuming that the partial observations of the system are contaminated by additive noise, we enable a principled mechanism to represent experimental uncertainties in the synthesis of the multicellular system and pave the way for the design of probabilistic methods for the estimation of any unknowns in the model. Within this setup, we tackle the Bayesian estimation of a subset of the model parameters. Specifically, we compare three Monte Carlo based numerical methods for the approximation of the posterior probability density function of the unknown parameters given a set of partial and noisy observations of the system. The schemes we assess are the particle Metropolis-Hastings (PMH) algorithm, the nonlinear population Monte Carlo (NPMC) method and the approximate Bayesian computation sequential Monte Carlo (ABC-SMC) scheme. We present an extensive numerical simulation study, which shows that while the three techniques can effectively solve the problem there are significant differences both in estimation accuracy and computational efficiency. PMID:28797087

  15. Agricultural Water Conservation in the Colorado River Basin: Alternatives to Permanent Fallowing Research Synthesis and Outreach Workshops

    NASA Astrophysics Data System (ADS)

    Udall, B. H.; Peterson, G.

    2017-12-01

    As increasing water scarcity occurs in the Colorado River Basin, water users have been looking for new sources of supply. The default solution is to transfer water from the cheapest and most plentiful source — agriculture — to supply new water demands in the region. However, if pursued in haste, and without sufficient information, the likely outcome may be permanent fallowing, along with serious economic disruption to agricultural communities, loss of valuable farmland, loss of important amenity values, and a loss of a sense of place in many rural communities within the basin. This project was undertaken to explore ways to minimize harm to agriculture if transfers out of agriculture were to occur. Four detailed synthesis reports of the four common methods used to temporarily transfer water from agriculture were produced by the project. The water saving methods covered by the reports are: (1) Deficit Irrigation of Alfalfa and other Forages; (2) Rotational Fallowing; (3) Crop Switching; and (4) Irrigation Efficiency and Water Conservation After the reports were drafted, three workshops were held, one in the Upper Basin in Grand Junction on November 4, 2016, one in the Lower Basin in Tucson on March 29, 2017, and one in Washington, DC on May 16, 2017 to disseminate the findings. Over 100 people attended these workshops.

  16. Moderate Baseline Vagal Tone Predicts Greater Prosociality in Children

    PubMed Central

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

    2016-01-01

    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 association (inverted U-shape curve) between baseline vagal tone and prosociality (Kogan et al., 2014). The present research examined whether this nonlinear association was evident in children. We found consistent evidence for a quadratic relation between vagal tone and prosociality across 3 samples of children using 6 different measures. Compared to low and high vagal tone, moderate vagal tone in early childhood concurrently predicted greater self-reported prosociality (Study 1), observed empathic concern in response to the distress of others and greater generosity toward less fortunate peers (Study 2), and longitudinally predicted greater self-, mother-, and teacher-reported prosociality 5.5 years later in middle childhood (Study 3). Taken together, our findings suggest that moderate vagal tone at rest represents a physiological preparedness or tendency to engage in different forms of prosociality across different contexts. Early moderate vagal tone may reflect an optimal balance of regulation and arousal that helps prepare children to sympathize, comfort, and share with others. PMID:27819463

  17. 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.

  18. Radio-frequency measurement of an asymmetric single electron transistor

    NASA Astrophysics Data System (ADS)

    Ji, Zhongqing; Xue, Weiwei; Rimberg, A. J.

    2007-03-01

    Since the invention of the radio-frequency single-electron transistor (RF-SET) by Schoelkopf et al.,[1] most measurements have focused on the symmetric single electron transistor. It has been shown, however, that the symmetric SET has a rather low measurement efficiency in its normal working regime.[2][3] Recently, it has been pointed out that an asymmetric SET can be considerably more efficient than a symmetric SET as a quantum amplifier. In this case the measurement efficiency of the asymmetric SET becomes similar to that of the quantum point contact (QPC) detector which can approach the quantum limit. We investigate the asymmetric SET by fabricating Al/AlOx SETs with junction areas 40x40 nm^2 and 40x80nm^2 and total resistance of about 25kφ. The results of RF and DC characterization of such asymmetric SETs will be discussed. [1] R. J. Schoelkopf, P. Wahlgren, A. A. Kozhevnikov, P. Delsing, D. E. Prober, Science, 280, 1242 (1998). [2] A. N. Korotkov, Phys. Rev. B, 63, 085312 (2001); 63, 115403 (2001). [3] D. Mozyrsky, I. Martin, and M. B. Hastings, Phys. Rev. Lett., 92, 018303 (2004). [4] S. A. Gurvitz and G. P. Berman, Phys. Rev. B, 72 , 073303(2005).

  19. Mitochondrial Replacement Techniques, Scientific Tourism, and the Global Politics of Science.

    PubMed

    Chan, Sarah; Palacios-González, César; De Jesús Medina Arellano, María

    2017-09-01

    The United Kingdom is the first and so far only country to pass explicit legislation allowing for the licensed use of the new reproductive technology known as mitochondrial replacement therapy. The techniques used in this technology may prevent the transmission of mitochondrial DNA diseases, but they are controversial because they involve the manipulation of oocytes or embryos and the transfer of genetic material. Some commentators have even suggested that MRT constitutes germline genome modification. All eyes were on the United Kingdom as the most likely location for the first MRT birth, so it was a shock when, on September 27, 2016, an announcement went out that the first baby to result from use of the intervention had already been born. In New York City, United States-based scientist John Zhang used maternal spindle transfer (one of the recognized MRT methods) to generate five embryos for a woman carrying oocytes with deleterious mutations of the mitochondrial DNA. Zhang then shipped the only euploid embryo to Mexico, where it was transferred to the mother's uterus. Zhang's team's travel across international borders to carry out experimental procedures represents a form of scientific tourism that has not been properly ethically explored; it can, however, have seriously detrimental effects for developing countries. © 2017 The Hastings Center.

  20. Progress: Its Glories and Pitfalls.

    PubMed

    Callahan, Daniel

    2018-03-01

    Steven Pinker, a cognitive psychologist and linguist at Harvard and a savant of big ideas, is one of the latest to take on the idea of progress. He does it under the aegis of "enlightenment," which comes down to a kind of holy trinity of reason, science, and humanism. His new book, Enlightenment Now: The Case for Reason, Science, Humanism, and Progress, is ambitious and cantankerous and heady with hope. On the whole, Pinker makes a good case for the benefits of progress, but with an overdose of feel-good prose. His greatest failure comes in exaggerating the threats to science and in avoiding some problems altogether. He ignores its complexity, its shadows, its creation of new problems raised by its solutions to old ones. Pinker has a particular animus against bioethics, and he misses what has been, I would argue, at the heart of bioethics from its beginning fifty or so years ago. Bioethics was prompted by a new class of medical dilemmas that require a difficult balancing of harms and benefits. Most of them are still with us, and most of them are the result of the progress of postwar medical research and fast-changing clinical practices. © 2018 The Hastings Center.

  1. Politics and Public Health: The Flint Drinking Water Crisis.

    PubMed

    Gostin, Lawrence O

    2016-07-01

    The Flint, Michigan, lead drinking water crisis is perhaps the most vivid current illustration of health inequalities in the United States. Since 2014, Flint citizens-among the poorest in America, mostly African American-had complained that their tap water was foul and discolored. But city, state, and federal officials took no heed. In March 2016, an independent task force found fault at every level of government and also highlighted what may amount to criminal negligence for workers who seemingly falsified water-quality results, allowing the people of Flint to continue to be exposed to water well above the federally allowed lead levels. It would have been possible to prevent lead seeping into the drinking water by treating the pipes with federally approved anticorrosives for around $100 per day. But today the cost of repairing the Flint water system is estimated at $1.5 billion, and fixing the ageing and lead-laden system across the United States would cost at least $1.3 trillion. How will Flint residents get justice and fair compensation for the wrongs caused by individual and systemic failures? And how will governments rebuild a water infrastructure that is causing and will continue to cause toxic conditions, particularly in economically marginalized cities and towns across America? © 2016 The Hastings Center.

  2. Successive equimarginal approach for optimal design of a pump and treat system

    NASA Astrophysics Data System (ADS)

    Guo, Xiaoniu; Zhang, Chuan-Mian; Borthwick, John C.

    2007-08-01

    An economic concept-based optimization method is developed for groundwater remediation design. Design of a pump and treat (P&T) system is viewed as a resource allocation problem constrained by specified cleanup criteria. An optimal allocation of resources requires that the equimarginal principle, a fundamental economic principle, must hold. The proposed method is named successive equimarginal approach (SEA), which continuously shifts a pumping rate from a less effective well to a more effective one until equal marginal productivity for all units is reached. Through the successive process, the solution evenly approaches the multiple inequality constraints that represent the specified cleanup criteria in space and in time. The goal is to design an equal protection system so that the distributed contaminant plumes can be equally contained without bypass and overprotection is minimized. SEA is a hybrid of the gradient-based method and the deterministic heuristics-based method, which allows flexibility in dealing with multiple inequality constraints without using a penalty function and in balancing computational efficiency with robustness. This method was applied to design a large-scale P&T system for containment of multiple plumes at the former Blaine Naval Ammunition Depot (NAD) site, near Hastings, Nebraska. To evaluate this method, the SEA results were also compared with those using genetic algorithms.

  3. EXOFIT: orbital parameters of extrasolar planets from radial velocities

    NASA Astrophysics Data System (ADS)

    Balan, Sreekumar T.; Lahav, Ofer

    2009-04-01

    Retrieval of orbital parameters of extrasolar planets poses considerable statistical challenges. Due to sparse sampling, measurement errors, parameters degeneracy and modelling limitations, there are no unique values of basic parameters, such as period and eccentricity. Here, we estimate the orbital parameters from radial velocity data in a Bayesian framework by utilizing Markov Chain Monte Carlo (MCMC) simulations with the Metropolis-Hastings algorithm. We follow a methodology recently proposed by Gregory and Ford. Our implementation of MCMC is based on the object-oriented approach outlined by Graves. We make our resulting code, EXOFIT, publicly available with this paper. It can search for either one or two planets as illustrated on mock data. As an example we re-analysed the orbital solution of companions to HD 187085 and HD 159868 from the published radial velocity data. We confirm the degeneracy reported for orbital parameters of the companion to HD 187085, and show that a low-eccentricity orbit is more probable for this planet. For HD 159868, we obtained slightly different orbital solution and a relatively high `noise' factor indicating the presence of an unaccounted signal in the radial velocity data. EXOFIT is designed in such a way that it can be extended for a variety of probability models, including different Bayesian priors.

  4. Being Better Bodies.

    PubMed

    Reynolds, Joel Michael

    2017-11-01

    Bioethics has an uneasy relationship with embodiment. Only with vigilance does knowledge of the body as it is lived counterbalance the momentous inertia of knowledge of the body as an object brought about by modern medical sciences. As a field tethered to detached, technical ways of knowing the world, bioethics must toil to treat the body as more than mere material and machine. To be more is, among other things, to be social-to live in the thickets of interdependence and the institutions and practices we build, hone, and defend to facilitate it. I take this tension to define the ultimate stakes of Melinda Hall's The Bioethics of Enhancement: Transhumanism, Disability, and Biopolitics. Hall homes in on transhumanism, the idea that we should embrace technology to vault beyond current human limitations. Yet the work serves as a reminder for all bioethicists and philosophers of how easily one can be led astray by otherwise irreproachable values when they are disconnected from the conditions and realities of human life, including being irremediably interdependent embodied beings. Put more acerbically, the book is a reminder of how thinking goes wrong when divorced from the principal sources out of which human appraisals emerge: our fleshy, messy, social bodies. © 2017 The Hastings Center.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. The Full Monte Carlo: A Live Performance with Stars

    NASA Astrophysics Data System (ADS)

    Meng, Xiao-Li

    2014-06-01

    Markov chain Monte Carlo (MCMC) is being applied increasingly often in modern Astrostatistics. It is indeed incredibly powerful, but also very dangerous. It is popular because of its apparent generality (from simple to highly complex problems) and simplicity (the availability of out-of-the-box recipes). It is dangerous because it always produces something but there is no surefire way to verify or even diagnosis that the “something” is remotely close to what the MCMC theory predicts or one hopes. Using very simple models (e.g., conditionally Gaussian), this talk starts with a tutorial of the two most popular MCMC algorithms, namely, the Gibbs Sampler and the Metropolis-Hasting Algorithm, and illustratestheir good, bad, and ugly implementations via live demonstration. The talk ends with a story of how a recent advance, the Ancillary-Sufficient Interweaving Strategy (ASIS) (Yu and Meng, 2011, http://www.stat.harvard.edu/Faculty_Content/meng/jcgs.2011-article.pdf)reduces the danger. It was discovered almost by accident during a Ph.D. student’s (Yaming Yu) struggle with fitting a Cox process model for detecting changes in source intensity of photon counts observed by the Chandra X-ray telescope from a (candidate) neutron/quark star.

  10. A new moving strategy for the sequential Monte Carlo approach in optimizing the hydrological model parameters

    NASA Astrophysics Data System (ADS)

    Zhu, Gaofeng; Li, Xin; Ma, Jinzhu; Wang, Yunquan; Liu, Shaomin; Huang, Chunlin; Zhang, Kun; Hu, Xiaoli

    2018-04-01

    Sequential Monte Carlo (SMC) samplers have become increasing popular for estimating the posterior parameter distribution with the non-linear dependency structures and multiple modes often present in hydrological models. However, the explorative capabilities and efficiency of the sampler depends strongly on the efficiency in the move step of SMC sampler. In this paper we presented a new SMC sampler entitled the Particle Evolution Metropolis Sequential Monte Carlo (PEM-SMC) algorithm, which is well suited to handle unknown static parameters of hydrologic model. The PEM-SMC sampler is inspired by the works of Liang and Wong (2001) and operates by incorporating the strengths of the genetic algorithm, differential evolution algorithm and Metropolis-Hasting algorithm into the framework of SMC. We also prove that the sampler admits the target distribution to be a stationary distribution. Two case studies including a multi-dimensional bimodal normal distribution and a conceptual rainfall-runoff hydrologic model by only considering parameter uncertainty and simultaneously considering parameter and input uncertainty show that PEM-SMC sampler is generally superior to other popular SMC algorithms in handling the high dimensional problems. The study also indicated that it may be important to account for model structural uncertainty by using multiplier different hydrological models in the SMC framework in future study.

  11. Editors' Introduction: Abstract Concepts: Structure, Processing, and Modeling.

    PubMed

    Bolognesi, Marianna; Steen, Gerard

    2018-06-22

    Our ability to deal with abstract concepts is one of the most intriguing faculties of human cognition. Still, we know little about how such concepts are formed, processed, and represented in mind. For example, because abstract concepts do not designate referents that can be experienced through our body, the role of perceptual experiences in shaping their content remains controversial. Current theories suggest a variety of alternative explanations to the question of "how abstract concepts are represented in the human mind." These views pinpoint specific streams of semantic information that would play a prominent role in shaping the content of abstract concepts, such as situation-based information (e.g., Barsalou & Wiemer-Hastings, ), affective information (Kousta, Vigliocco, Vinson, Andrews, & Del Campo, ), and linguistic information (Louwerse, ). Rarely, these theoretical views are directly compared. In this special issue, current views are presented in their most recent and advanced form, and directly compared and discussed in a debate, which is reported at the end of each article. As a result, new exciting questions and challenges arise. These questions and challenges, reported in this introductory article, can arguably pave the way to new empirical studies and theoretical developments on the nature of abstract concepts. © 2018 Cognitive Science Society, Inc.

  12. Pharmaceutical Company Corruption and the Moral Crisis in Medicine.

    PubMed

    Batt, Sharon

    2016-07-01

    A much-debated series of articles in the New England Journal of Medicine in May 2015 labeled the pharmaceutical industry's critics "pharmascolds." Having followed the debate for two decades, I count myself among the scolds. The weight of the evidence overwhelmingly supports the claim that pharmaceutical policy no longer serves the public interest; the central questions now are how this happened and what to do about it. I approached three of the most recent books on the industry with these questions in mind. Deadly Medicine and Organized Crime (CRC Press, 2013), by Peter Gøtzsche, Bad Pharma (Faber & Faber, 2013), by Ben Goldacre, and Good Pharma (Palgrave MacMillan, 2015), by Donald Light and Antonio Maturo, all situate their critical assessments in high-income countries globally, depicting the problem of pharmaceuticals as too many drugs approved with too little evidence, causing too many needless deaths, and prices spiraling to heights unimaginable just a decade ago. Light and Maturo, while no less critical of the status quo than Gøtzsche and Goldacre, take a different tack: they detail the success of an alternative model for pharmaceutical research, the Mario Negri Institute in Italy, citing it as proof positive that we can indeed defy capitalism's profit imperative. © 2016 The Hastings Center.

  13. 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

    2018-01-01

    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 an 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.

  14. Ethics Hype?

    PubMed

    Caulfield, Timothy

    2016-09-01

    There has been growing concern about the phenomenon of science hype, the tendency to exaggerate the value or near-future application of research results. Although this is a problem that touches every area of biomedicine, the topic of genetics seems to be particularly prone to enthusiastic predictions. The world has been told for over two decades-by the media, researchers, politicians, and the biotech industry-that a genome-driven health care revolution is just around the corner. And while the revolution never seems to arrive, the hopeful rhetoric continues. It has been suggested that this unrelenting "genohype" is having a range of adverse social consequences, including misleading the public and hurting the long-term legitimacy of the field. While we need more good data on the nature and magnitude of these possible harms, few would argue with the proposition that sustained science hype is a bad thing. We all benefit from robust science and accurate public representations of biomedical research. But, to date, there has been very little consideration of the degree to which the scholarship on the related ethical, legal, and social issues has been hyped. Are the conclusions from ELSI scholarship also exaggerated? © 2016 The Hastings Center.

  15. Setting health care priorities: Oregon's next steps.

    PubMed

    Dougherty, Charles J

    1991-01-01

    Since the proposal was first broached in 1987, a storm of controversy has engulfed Oregon's plan to prioritize the health care services offered to its Medicaid recipients. After two years of debate, community consultation, and public opinion polls, the Oregon Health Services Commission was mandated in 1989 to study prioritization as part of a package of bills enacted as the Oregon Basic Health Services Act. In March 1990 the commission released a draft list of ranked health care services for public comment... As part of the ongoing debate, the Hastings Center and the Wesley Foundation sponsored a two-day meeting in January 1991 in Wichita, Kansas, to provide opportunity for thoughtful, in-depth, informal analysis of the OBHSA model for health care reform...a majority felt that OBHSA, in the framework of progress toward larger reform goals, is an experiment worth trying. Some felt that even if OBHSA doesn't attain its larger goals it should be tried since it will extend access and may lead to better health outcomes among the poor. But the general view was that OBHSA is a valuable experiment only to the extent that it leads to a statewide system of universal health insurance in Oregon without creating special burdens for the state's poor....

  16. 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

  17. 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

  18. Learn-as-you-go acceleration of cosmological parameter estimates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aslanyan, Grigor; Easther, Richard; Price, Layne C., E-mail: g.aslanyan@auckland.ac.nz, E-mail: r.easther@auckland.ac.nz, E-mail: lpri691@aucklanduni.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 explicitlymore » 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.« less

  19. View of Minneapolis-St.Paul, Minnesota area

    NASA Image and Video Library

    1973-08-30

    SL3-28-009 (July-September 1973) --- A near vertical view of the Minneapolis-St. Paul, Minnesota area, as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment in the Multiple Docking Adapter of the Skylab space station. A 150mm lens, with SO-356 high definition Ektachrome film, was used to take this picture. The Mississippi River flows southeasterly through this large metropolitan area. Minneapolis is on the west bank of the Mississippi. The Minnesota River makes a large bend at the southern edge of the picture then flows northeasterly to empty into the Mississippi at Minneapolis-St. Paul. The St. Croix River, which serves as a portion of the boundary between Minnesota and Wisconsin, flows into the Mississippi downstream from the twin cities. A long, nearly straight, stretch of Interstate 35 leads southward from Minneapolis-St. Paul. Interstate 94 parallels the Mississippi toward the northwest. The highway and road network in the area is clearly visible. Note the numerous small lakes in the photograph. This view includes the smaller cities of Hastings, Faribault, Owatonna, Mankato, St. Peter, New Ulm and St. Cloud. The S190-A experiment is part of the Skylab Earth Resources Experiments Package. Photo credit: NASA

  20. Land subsidence associated with hydrocarbon production, Texas Gulf Coast

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kreitler, C.W.; White, W.A.; Akhter, M.S.

    1988-01-01

    Although ground-water withdrawal has been the predominant cause of land subsidence in the Texas Gulf Coast, localized subsidence and faulting have also resulted from hydrocarbon production. Subsidence was documented as early as the 1920s over the Goose Creek field. Since then, subsidence and/or faulting have been identified over the Saxet, South Houston, Chocolate Bayou, Hastings, Alco-Mag, Clinton, Mykawa, Blue Ridge, Webster, and Caplen oil fields. Oil-production-related subsidence over these fields generally creates few environmental or engineering problems. One exception is the subsidence and faulting over the Caplen oil field on Bolivar Peninsula, where more than 1,000 ac of saltwater marshmore » has been replaced by subaqueous flats. Subsidence may be occurring over other fields but has not been identified because of limited releveled benchmark data. An evaluation of drill-stem and bottom-hole pressure data for the Frio Formation in Texas indicates extensive depressurization presumably from hydrocarbon production. Nearly 12,000 measurements from a pressure data base of 17,000 measurements indicate some depressurization. Some of the Frio zones have pressure declines of more than 1,500 psi from original hydrostatic conditions. Subsidence and faulting may be associated with these fields in the Frio as well as other Tertiary formations where extensive hydrocarbon production and subsequent depressurization have occurred.« less

  1. An Improved Nested Sampling Algorithm for Model Selection and Assessment

    NASA Astrophysics Data System (ADS)

    Zeng, X.; Ye, M.; Wu, J.; WANG, D.

    2017-12-01

    Multimodel strategy is a general approach for treating model structure uncertainty in recent researches. The unknown groundwater system is represented by several plausible conceptual models. Each alternative conceptual model is attached with a weight which represents the possibility of this model. In Bayesian framework, the posterior model weight is computed as the product of model prior weight and marginal likelihood (or termed as model evidence). As a result, estimating marginal likelihoods is crucial for reliable model selection and assessment in multimodel analysis. Nested sampling estimator (NSE) is a new proposed algorithm for marginal likelihood estimation. The implementation of NSE comprises searching the parameters' space from low likelihood area to high likelihood area gradually, and this evolution is finished iteratively via local sampling procedure. Thus, the efficiency of NSE is dominated by the strength of local sampling procedure. Currently, Metropolis-Hasting (M-H) algorithm and its variants are often used for local sampling in NSE. However, M-H is not an efficient sampling algorithm for high-dimensional or complex likelihood function. For improving the performance of NSE, it could be feasible to integrate more efficient and elaborated sampling algorithm - DREAMzs into the local sampling. In addition, in order to overcome the computation burden problem of large quantity of repeating model executions in marginal likelihood estimation, an adaptive sparse grid stochastic collocation method is used to build the surrogates for original groundwater model.

  2. Reproductive Rights without Resources or Recourse.

    PubMed

    Mutcherson, Kimberly

    2017-12-01

    The U.S. Supreme Court declared procreation to be a fundamental right in the early twentieth century in a case involving Oklahoma's Habitual Criminal Sterilization Act, an act that permitted unconsented sterilization of individuals convicted of certain crimes. The right that the Court articulated in that case is a negative right: it requires that the government not place unjustified roadblocks in the way of people seeking to procreate, but it does not require the government to take positive steps to help people procreate if they wish to. I argue that a positive legal right is morally necessary in the United States, given the profound significance of procreation, the current barriers to access to care, and the related issues of individual and societal justice. I assume at the outset that the right to procreate should be expansive enough to include a right to noncoital reproduction. The absence of a positive right to procreate reflects not just constitutional tradition but also a governmental and societal commitment to a longstanding set of reproductive hierarchies by which those who fall outside of the traditional framing of family too frequently find their procreative dreams hindered. Reconceiving procreative rights to include a positive right would create greater opportunities to argue and lobby for increased access to technologies that are out of reach for many. © 2017 The Hastings Center.

  3. Functional neuroimaging: technical, logical, and social perspectives.

    PubMed

    Aguirre, Geoffrey K

    2014-01-01

    Neuroscientists have long sought to study the dynamic activity of the human brain-what's happening in the brain, that is, while people are thinking, feeling, and acting. Ideally, an inside look at brain function would simultaneously and continuously measure the biochemical state of every cell in the central nervous system. While such a miraculous method is science fiction, a century of progress in neuroimaging technologies has made such simultaneous and continuous measurement a plausible fiction. Despite this progress, practitioners of modern neuroimaging struggle with two kinds of limitations: those that attend the particular neuroimaging methods we have today and those that would limit any method of imaging neural activity, no matter how powerful. In this essay, I consider the liabilities and potential of techniques that measure human brain activity. I am concerned here only with methods that measure relevant physiologic states of the central nervous system and relate those measures to particular mental states. I will consider in particular the preeminent method of functional neuroimaging: BOLD fMRI. While there are several practical limits on the biological information that current technologies can measure, these limits-as important as they are-are minor in comparison to the fundamental logical restraints on the conclusions that can be drawn from brain imaging studies. © 2014 by The Hastings Center.

  4. Neuroimaging: beginning to appreciate its complexities.

    PubMed

    Parens, Erik; Johnston, Josephine

    2014-01-01

    For over a century, scientists have sought to see through the protective shield of the human skull and into the living brain. Today, an array of technologies allows researchers and clinicians to create astonishingly detailed images of our brain's structure as well as colorful depictions of the electrical and physiological changes that occur within it when we see, hear, think and feel. These technologies-and the images they generate-are an increasingly important tool in medicine and science. Given the role that neuroimaging technologies now play in biomedical research, both neuroscientists and nonexperts should aim to be as clear as possible about how neuroimages are made and what they can-and cannot-tell us. Add to this that neuroimages have begun to be used in courtrooms at both the determination of guilt and sentencing stages, that they are being employed by marketers to refine advertisements and develop new products, that they are being sold to consumers for the diagnosis of mental disorders and for the detection of lies, and that they are being employed in arguments about the nature (or absence) of powerful concepts like free will and personhood, and the need for citizens to have a basic understanding of how this technology works and what it can and cannot tell us becomes even more pressing. © 2014 by The Hastings Center.

  5. Reclaiming Hope in Extinction Storytelling.

    PubMed

    Kohl, Patrice

    2017-07-01

    Critics often take conservationists to task for delivering a constant barrage of bad news without offering a compelling vision of the future. Could recent advances in synthetic biology-an optimistic, forward-looking field with a can-do attitude-let conservationists develop a new vision and generate some better news? Synthetic biology and related gene-editing applications could be used to address threats to species. Genetic interventions might also be used in plants to better protect biodiversity in U.S. rangelands and forests. One possibility has stood out in its ability to capture media attention and the public imagination-recreating extinct species. And perhaps a de-extinction story could counter the seemingly relentless negativity in biodiversity talk. De-extinction proponent Stewart Brand writes that resurrecting species could shift the "conservation story … from negative to positive, from constant whining and guilt-tripping to high fives and new excitement." So, why do many people in conservation oppose the de-extinction narrative? This essay is an inquiry into whether there are intrinsic social reactions to these types of conservation solutions that might offset their potential benefits. If genetic tools are to be applied to address conservation issues in a realistic and responsible way, their broader social-cultural implications deserve far more attention than they have so far received. © 2017 The Hastings Center.

  6. Delegating Informed Consent.

    PubMed

    Koch, Valerie Gutmann

    2017-11-01

    Ten years ago, Megan Shinal sought the care of neurosurgeon Steven Toms for the surgical treatment of a recurrent nonmalignant tumor in the pituitary region of her brain. In their twenty-minute meeting, Shinal did not make a final decision about which surgical approach she wished to pursue. Subsequently, she spoke with Tom's physician assistant once by phone and once in person, when she signed the consent form, which did not appear to designate which surgical approach she had chosen. During the operation-a total resection-Toms perforated Shinal's carotid artery, resulting in hemorrhage, stroke, brain injury, and partial blindness. The jury found that Toms had fulfilled his informed-consent obligations prior to performing the resection; however, in June 2017, the Supreme Court of Pennsylvania overturned the decision, relying on the Pennsylvania Medical Care Availability and Reduction of Error Act. The court found that the language of the act is unambiguous in its requirement that "a physician's duty to provide information to a patient sufficient to obtain her informed consent is non-delegable." Presumably, this rule of nondelegation applies beyond the surgical theater to other major treatment decisions. And it is unclear whether it applies to other professionals in a subordinate position to the treating physician, such as residents and fellows. © 2017 The Hastings Center.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gencaga, Deniz; Knuth, Kevin H.; Carbon, Duane F.

    Understanding the origins of life has been one of the greatest dreams throughout history. It is now known that star-forming regions contain complex organic molecules, known as Polycyclic Aromatic Hydrocarbons (PAHs), each of which has particular infrared spectral characteristics. By understanding which PAH species are found in specific star-forming regions, we can better understand the biochemistry that takes place in interstellar clouds. Identifying and classifying PAHs is not an easy task: we can only observe a single superposition of PAH spectra at any given astrophysical site, with the PAH species perhaps numbering in the hundreds or even thousands. This ismore » a challenging source separation problem since we have only one observation composed of numerous mixed sources. However, it is made easier with the help of a library of hundreds of PAH spectra. In order to separate PAH molecules from their mixture, we need to identify the specific species and their unique concentrations that would provide the given mixture. We develop a Bayesian approach for this problem where sources are separated from their mixture by Metropolis Hastings algorithm. Separated PAH concentrations are provided with their error bars, illustrating the uncertainties involved in the estimation process. The approach is demonstrated on synthetic spectral mixtures using spectral resolutions from the Infrared Space Observatory (ISO). Performance of the method is tested for different noise levels.« less

  8. Bayesian inference of spectral induced polarization parameters for laboratory complex resistivity measurements of rocks and soils

    NASA Astrophysics Data System (ADS)

    Bérubé, Charles L.; Chouteau, Michel; Shamsipour, Pejman; Enkin, Randolph J.; Olivo, Gema R.

    2017-08-01

    Spectral induced polarization (SIP) measurements are now widely used to infer mineralogical or hydrogeological properties from the low-frequency electrical properties of the subsurface in both mineral exploration and environmental sciences. We present an open-source program that performs fast multi-model inversion of laboratory complex resistivity measurements using Markov-chain Monte Carlo simulation. Using this stochastic method, SIP parameters and their uncertainties may be obtained from the Cole-Cole and Dias models, or from the Debye and Warburg decomposition approaches. The program is tested on synthetic and laboratory data to show that the posterior distribution of a multiple Cole-Cole model is multimodal in particular cases. The Warburg and Debye decomposition approaches yield unique solutions in all cases. It is shown that an adaptive Metropolis algorithm performs faster and is less dependent on the initial parameter values than the Metropolis-Hastings step method when inverting SIP data through the decomposition schemes. There are no advantages in using an adaptive step method for well-defined Cole-Cole inversion. Finally, the influence of measurement noise on the recovered relaxation time distribution is explored. We provide the geophysics community with a open-source platform that can serve as a base for further developments in stochastic SIP data inversion and that may be used to perform parameter analysis with various SIP models.

  9. Public Health Autonomy: A Critical Reappraisal.

    PubMed

    Zimmerman, Frederick J

    2017-11-01

    The ethical principle of autonomy is among the most fundamental in ethics, and it is particularly salient for those in public health, who must constantly balance the desire to improve health outcomes by changing behavior with respect for individual freedom. Although there are some areas in which there is a genuine tension between public health and autonomy-childhood vaccine mandates, for example-there are many more areas where not only is there no tension, but public health and autonomy come down to the same thing. These areas of overlap are often rendered invisible by a thin understanding of autonomy. Better integrating newer theoretical insights about autonomy into applied ethics can make discussions of public health ethics more rigorous, incisive, and effective. Even more importantly, bringing modern concepts of autonomy into public health ethics can showcase the many areas in which public health and autonomy have the same goals, face the same threats, and can be mutually advanced by the same kinds of solutions. This article provides a schema for relational autonomy in a public health context and gives concrete examples of how autonomy can be served through public-health interventions. It marshals insights from sociology, psychology, and philosophy to advance a theory of autonomy and coercion that recognizes three potential threats to autonomy: threats to choice sets, threats to knowledge, and threats to preferences. © 2017 The Hastings Center.

  10. Parameter-induced uncertainty quantification of crop yields, soil N2O and CO2 emission for 8 arable sites across Europe using the LandscapeDNDC model

    NASA Astrophysics Data System (ADS)

    Santabarbara, Ignacio; Haas, Edwin; Kraus, David; Herrera, Saul; Klatt, Steffen; Kiese, Ralf

    2014-05-01

    When using biogeochemical models to estimate greenhouse gas emissions at site to regional/national levels, the assessment and quantification of the uncertainties of simulation results are of significant importance. The uncertainties in simulation results of process-based ecosystem models may result from uncertainties of the process parameters that describe the processes of the model, model structure inadequacy as well as uncertainties in the observations. Data for development and testing of uncertainty analisys were corp yield observations, measurements of soil fluxes of nitrous oxide (N2O) and carbon dioxide (CO2) from 8 arable sites across Europe. Using the process-based biogeochemical model LandscapeDNDC for simulating crop yields, N2O and CO2 emissions, our aim is to assess the simulation uncertainty by setting up a Bayesian framework based on Metropolis-Hastings algorithm. Using Gelman statistics convergence criteria and parallel computing techniques, enable multi Markov Chains to run independently in parallel and create a random walk to estimate the joint model parameter distribution. Through means distribution we limit the parameter space, get probabilities of parameter values and find the complex dependencies among them. With this parameter distribution that determines soil-atmosphere C and N exchange, we are able to obtain the parameter-induced uncertainty of simulation results and compare them with the measurements data.

  11. Can Research on the Genetics of Intelligence Be "Socially Neutral"?

    PubMed

    Roberts, Dorothy

    2015-01-01

    The history of research on the genetics of intelligence is fraught with social bias. During the eugenics era, the hereditary theory of intelligence justified policies that encouraged the proliferation of favored races and coercively stemmed procreation by disfavored ones. In the 1970s, Berkeley psychologist Arthur Jensen argued that black students' innate cognitive inferiority limited the efficacy of federal education programs. The 1994 controversial bestseller The Bell Curve, by Richard J. Herrnstein and Charles Murray, rehashed the claim that race and class disparities stem from immutable differences in inherited intelligence, which could not be eliminated through social interventions. Today most scientists studying the genetics of intelligence distance themselves from this history of social bias by arguing that their research need not investigate intellectual differences between social groups. Rather, they argue, examining the heritability of intelligence can be socially neutral and may even help to reduce social inequities. I argue, however, that research on the genetics of intelligence cannot be socially neutral. Even if we divorce the heritability of intelligence from a eugenicist mission, measuring intelligence remains useful only as a gage of individuals' appropriate positions in society. Research into the genetics of intelligence ultimately helps to determine individuals' inherited capacity for particular social positions, even when researchers aim to modify the effects of inheritance. © 2015 The Hastings Center.

  12. 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.

  13. Spatial-Temporal Data Collection with Compressive Sensing in Mobile Sensor Networks

    PubMed Central

    Li, Jiayin; Guo, Wenzhong; Chen, Zhonghui; Xiong, Neal

    2017-01-01

    Compressive sensing (CS) provides an energy-efficient paradigm for data gathering in wireless sensor networks (WSNs). However, the existing work on spatial-temporal data gathering using compressive sensing only considers either multi-hop relaying based or multiple random walks based approaches. In this paper, we exploit the mobility pattern for spatial-temporal data collection and propose a novel mobile data gathering scheme by employing the Metropolis-Hastings algorithm with delayed acceptance, an improved random walk algorithm for a mobile collector to collect data from a sensing field. The proposed scheme exploits Kronecker compressive sensing (KCS) for spatial-temporal correlation of sensory data by allowing the mobile collector to gather temporal compressive measurements from a small subset of randomly selected nodes along a random routing path. More importantly, from the theoretical perspective we prove that the equivalent sensing matrix constructed from the proposed scheme for spatial-temporal compressible signal can satisfy the property of KCS models. The simulation results demonstrate that the proposed scheme can not only significantly reduce communication cost but also improve recovery accuracy for mobile data gathering compared to the other existing schemes. In particular, we also show that the proposed scheme is robust in unreliable wireless environment under various packet losses. All this indicates that the proposed scheme can be an efficient alternative for data gathering application in WSNs. PMID:29117152

  14. Multiscale implementation of infinite-swap replica exchange molecular dynamics.

    PubMed

    Yu, Tang-Qing; Lu, Jianfeng; Abrams, Cameron F; Vanden-Eijnden, Eric

    2016-10-18

    Replica exchange molecular dynamics (REMD) is a popular method to accelerate conformational sampling of complex molecular systems. The idea is to run several replicas of the system in parallel at different temperatures that are swapped periodically. These swaps are typically attempted every few MD steps and accepted or rejected according to a Metropolis-Hastings criterion. This guarantees that the joint distribution of the composite system of replicas is the normalized sum of the symmetrized product of the canonical distributions of these replicas at the different temperatures. Here we propose a different implementation of REMD in which (i) the swaps obey a continuous-time Markov jump process implemented via Gillespie's stochastic simulation algorithm (SSA), which also samples exactly the aforementioned joint distribution and has the advantage of being rejection free, and (ii) this REMD-SSA is combined with the heterogeneous multiscale method to accelerate the rate of the swaps and reach the so-called infinite-swap limit that is known to optimize sampling efficiency. The method is easy to implement and can be trivially parallelized. Here we illustrate its accuracy and efficiency on the examples of alanine dipeptide in vacuum and C-terminal β-hairpin of protein G in explicit solvent. In this latter example, our results indicate that the landscape of the protein is a triple funnel with two folded structures and one misfolded structure that are stabilized by H-bonds.

  15. Progressive Stochastic Reconstruction Technique (PSRT) for cryo electron tomography.

    PubMed

    Turoňová, Beata; Marsalek, Lukas; Davidovič, Tomáš; Slusallek, Philipp

    2015-03-01

    Cryo Electron Tomography (cryoET) plays an essential role in Structural Biology, as it is the only technique that allows to study the structure of large macromolecular complexes in their close to native environment in situ. The reconstruction methods currently in use, such as Weighted Back Projection (WBP) or Simultaneous Iterative Reconstruction Technique (SIRT), deliver noisy and low-contrast reconstructions, which complicates the application of high-resolution protocols, such as Subtomogram Averaging (SA). We propose a Progressive Stochastic Reconstruction Technique (PSRT) - a novel iterative approach to tomographic reconstruction in cryoET based on Monte Carlo random walks guided by Metropolis-Hastings sampling strategy. We design a progressive reconstruction scheme to suit the conditions present in cryoET and apply it successfully to reconstructions of macromolecular complexes from both synthetic and experimental datasets. We show how to integrate PSRT into SA, where it provides an elegant solution to the region-of-interest problem and delivers high-contrast reconstructions that significantly improve template-based localization without any loss of high-resolution structural information. Furthermore, the locality of SA is exploited to design an importance sampling scheme which significantly speeds up the otherwise slow Monte Carlo approach. Finally, we design a new memory efficient solution for the specimen-level interior problem of cryoET, removing all associated artifacts. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. De-extinction and Barriers to the Application of New Conservation Tools.

    PubMed

    Seddon, Philip J

    2017-07-01

    Decades of globally coordinated work in conservation have failed to slow the loss of biodiversity. To do better-even if that means nothing more than failing less spectacularly-bolder thinking is necessary. One of the first possible conservation applications of synthetic biology to be debated is the use of genetic tools to resurrect once-extinct species. Since the currency of conservation is biodiversity and the discipline of conservation biology was formed around the prevention of species extinctions, the prospect of reversing extinctions might have been expected to generate unreserved enthusiasm. But it was not universal acclaim that greeted the coming-out party for "de-extinction" that was the TEDx conference and accompanying National Geographic feature in 2013. Why the concern, the skepticism, even the hostility among many conservationists about the idea of restoring lost species? And how does this professional concern relate to public perception and support for conservation? This essay explores the barriers to the acceptance of risky new genomic-based conservation tools by considering five key areas and associated questions that could be addressed in relation to any new conservation tool. I illustrate these using the specific example of de-extinction, and in doing so, I consider whether de-extinction would necessarily be the best first point of engagement between conservation biology and synthetic biology. © 2017 The Hastings Center.

  17. 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.

  18. Making the Choices Necessary to Make a Difference: The Responsibility of National Bioethics Commissions.

    PubMed

    Grady, Christine

    2017-05-01

    In this essay, I offer some reflections on how the topics were identified and approached by the Presidential Commission for the Study of Bioethical Issues, on which I had the honor to serve, in the hope that the reflections may be useful to future national bioethics commissions. In the executive order that established the bioethics commission, President Obama explicitly recognized the ethical imperative to responsibly pursue science, innovation, and advances in biomedical research and health care, and the importance of national attention to these issues. The bioethics commission prioritized practicable, actionable, targeted recommendations. Like most earlier U.S. national bioethics commissions, President Obama's commission did not undertake projects on significant and troublesome issues related to health and health care that were not associated with new science or technology. Issues such as health care access, health care delivery, opioid addiction, end-of-life care, and physician-aid-in-dying are topical and ethically complex areas of significance to bioethics, and they are also being discussed and debated by the public, the media, and policy-makers. In my view, there are good reasons to select and prioritize projects as well as a justification for confining commission efforts to issues related to novel science and emerging technologies, when there is only one national-level bioethics commission that has been established by the Office of the President. © 2017 The Hastings Center.

  19. 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.

  20. Effect of Aluminum on Characterization of ZnTe/n-Si Heterojunction Photo detector

    NASA Astrophysics Data System (ADS)

    Maki, Samir A.; Hassun, Hanan K.

    2018-05-01

    Aluminum doped zinc telluride ZnTenSi thin films of (400nm) thickness with (005 01 015 and 02) wt % were deposited on the glass substrate and nSi wafer to fabricate ZnTenSi heterojunction Photodetector by using thermal vacuum evaporation technique Structural optical electrical and photovoltaic properties are investigated for the samples XRD analysis shows that all the deposited ZnTenSi films show polycrystalline structure with cubic phases and highest sharp peak corresponding to (111) planes and from AFM images shows the surface roughness increase with increase Al percentage ratio The optical absorption measurement of the films was find from transmittance ranges in the variety of wavelength (400 1000) nm and the optical energy band gap decrease from 224 eV to 186 eV dependent upon the Aluminum ratio in the films moreover our studies contain the calculation of the electrical properties of hetero junction were obtained via IV (dark and light condition) and C V measurement The photoelectric properties indicated rise illumination current of heterojunctions through increasing both of incident lighting intensity and Aluminum dopant The values of specific detectivity and quantum efficiency are calculated for all samples also the best spectral response occurs when Al doping ratio 02% The high photo sensitivity and comparatively fast response haste are attributable to in height crystal quality of the [ZnTe ] thin films.

  1. Spatial-Temporal Data Collection with Compressive Sensing in Mobile Sensor Networks.

    PubMed

    Zheng, Haifeng; Li, Jiayin; Feng, Xinxin; Guo, Wenzhong; Chen, Zhonghui; Xiong, Neal

    2017-11-08

    Compressive sensing (CS) provides an energy-efficient paradigm for data gathering in wireless sensor networks (WSNs). However, the existing work on spatial-temporal data gathering using compressive sensing only considers either multi-hop relaying based or multiple random walks based approaches. In this paper, we exploit the mobility pattern for spatial-temporal data collection and propose a novel mobile data gathering scheme by employing the Metropolis-Hastings algorithm with delayed acceptance, an improved random walk algorithm for a mobile collector to collect data from a sensing field. The proposed scheme exploits Kronecker compressive sensing (KCS) for spatial-temporal correlation of sensory data by allowing the mobile collector to gather temporal compressive measurements from a small subset of randomly selected nodes along a random routing path. More importantly, from the theoretical perspective we prove that the equivalent sensing matrix constructed from the proposed scheme for spatial-temporal compressible signal can satisfy the property of KCS models. The simulation results demonstrate that the proposed scheme can not only significantly reduce communication cost but also improve recovery accuracy for mobile data gathering compared to the other existing schemes. In particular, we also show that the proposed scheme is robust in unreliable wireless environment under various packet losses. All this indicates that the proposed scheme can be an efficient alternative for data gathering application in WSNs .

  2. What Is Bioethics Worth?

    PubMed

    Solomon, Mildred Z

    2016-09-01

    What is bioethics to do when it strives to assess the quality of its research and scholarship and when it needs to justify its work to prospective funders, especially a funder like the National Institutes of Health that privileges empirical discovery? In "A Conceptual Model for the Translation of Bioethics Research and Scholarship," Debra Mathews and colleagues take an important first step at advancing an answer. The authors describe what they call a translational process, whereby bioethics "outputs" are translated into changes of three types: in thinking, practice, and policy. It goes nearly without saying that bioethics research and scholarship must be held accountable for changes in thinking. What raison d'etre do we have if not to deepen thinking, question assumptions, and encourage ourselves and others to examine hard issues from novel approaches? Assuredly it is hard to assess quality, and even harder to assess specific changes in thinking for which high-quality scholarship may be responsible, but it is a necessary goal and one for which we should strive without reservation. Bioethics should also affect policy and practice. We should document how it does and the extent to which it does as often and as prominently as possible. However, let us be wary of pinning too much on practice and policy changes as the primary way of establishing bioethics' worth. © 2016 The Hastings Center.

  3. Geothermal Energy Production from Oil/Gas Wells and Application for Building Cooling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Honggang; Liu, Xiaobing

    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 amore » 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.« less

  4. Quantum Spin Liquids and Fractionalization

    NASA Astrophysics Data System (ADS)

    Misguich, Grégoire

    This chapter discusses quantum antiferromagnets which do not break any symmetries at zero temperature - also called "spin liquids" - and focuses on lattice spin models with Heisenberg-like (i.e. SU(2)-symmetric) interactions in dimensions larger than one. We begin by discussing the Lieb-Schultz-Mattis theorem and its recent extension to D > 1 by Hastings (2004), which establishes an important distinction between spin liquids with an integer and with a half-integer spin per unit cell. Spin liquids of the first kind, "band insulators", can often be understood by elementary means, whereas the latter, "Mott insulators", are more complex (featuring "topological order") and support spin-1/2 excitations (spinons). The fermionic formalism (Affleck and Marston, 1988) is described and the effect of fluctuations about mean-field solutions, such as the possible creation of instabilities, is discussed in a qualitative way. In particular, we explain the emergence of gauge modes and their relation to fractionalization. The concept of the projective symmetry group (X.-G. Wen, 2002) is introduced, with the aid of some examples. Finally, we present the phenomenology of (gapped) short-ranged resonating-valence-bond spin liquids, and make contact with the fermionic approach by discussing their description in terms of a fluctuating Z 2 gauge field. Some recent references are given to other types of spin liquid, including gapless ones.

  5. Medicare and Advance Planning: The Importance of Context.

    PubMed

    Dresser, Rebecca

    2016-05-01

    In January 2016, a long-delayed Medicare change took effect. The Medicare program will now reimburse doctors for time they spend talking with patients about end-of-life care. This is the move that Sarah Palin and other Affordable Care Act critics said would authorize government "death panels" to decide whether older Americans should live or die. Today virtually no one buys into Palin's death panel rhetoric. But many people do think the Medicare change is a big deal. Representative Earl Blumenauer, a Democrat from Oregon who sponsored the original ACA reimbursement proposal, lauded the Medicare provision as "a turning point in end-of-life care." Others are not so sure about that. After all, laws promoting advance care planning have existed for decades. The federal Patient Self-Determination Act of 1990 and the many court decisions and state laws supporting advance care planning have had relatively little impact. Similarly, legal recognition of physician orders for life-sustaining treatment as advance planning instruments have not produced the improvements that were predicted. And from a broad perspective, advance care planning is a small piece of the puzzle. The effort to improve end-of-life care must take into account the limitations of advance decision-making, as well as the overriding importance of the general standard of care for terminally ill patients. © 2016 The Hastings Center.

  6. Reprioritizing Research Activity for the Post-Antibiotic Era: Ethical, Legal, and Social Considerations.

    PubMed

    Hey, Spencer Phillips; Kesselheim, Aaron S

    2017-03-01

    Many hold that the so-called golden era of antibiotic discovery has passed, leaving only a limited clinical pipeline for new antibiotics. A logical conclusion of such arguments is that we need to reform the current system of antibiotic drug research-including clinical trials and regulatory requirements-to spur activity in discovery and development. The United States Congress in the past few years has debated a number of bills to address this crisis, including the 2012 Generating Antibiotic Incentives Now Act and the 2016 21st Century Cures Act. Experts have also sought to advance antibiotic development by encouraging greater use of trials with noninferiority hypotheses, which are thought to be easier to conduct. The goal underlying these proposals is to stave off the post-antibiotic era by expanding the pharmaceutical armamentarium as quickly as possible. But although new antibiotic agents are necessary to combat the long-term threat of drug-resistant disease, we argue that these research policies, which effectively lower the bar for antibiotic approval, are ethically problematic. Rather, given broader public health considerations related to the full lifecycle of antibiotic use-including development of resistance-we should reject an overly permissive approach to new antibiotic approval and instead set the bar for regulatory approval at a point that will naturally direct research resources toward the most transformative chemical or social interventions. © 2017 The Hastings Center.

  7. Real-World Evidence, Public Participation, and the FDA.

    PubMed

    Schwartz, Jason L

    2017-11-01

    For observers of pharmaceutical regulation and the Food and Drug Administration, these are uncertain times. Events in late 2016 raised concerns that the FDA's evidentiary standards were being weakened, compromising the agency's ability to adequately perform its regulatory and public health responsibilities. Two developments most directly contributed to these fears-the approval of eteplirsen, a treatment for Duchenne muscular dystrophy, against the recommendations of both FDA staff and an advisory committee and the December 2016 signing of the 21st Century Cures Act, which encouraged greater use by the FDA of "real-world" evidence not obtained through randomized controlled trials. The arrival of the Trump administration-with its deregulatory, industry-friendly approach-has only amplified concerns over the future of the FDA. It is too early to know whether the recent developments are truly harbingers of an FDA less likely to prevent unsafe or ineffective products from reaching the market. But elements in the two events-the role of patient narratives in deliberations regarding eteplirsen and the enthusiasm for real-world evidence in the 21st Century Cures Act-raise critical issues for the future of evidence in the FDA's work. The rigorous, inclusive approach under way to consider issues related to real-world evidence provides a model for a similarly needed inquiry regarding public participation in FDA decision-making. © 2017 The Hastings Center.

  8. Student Workshops for Severe Weather Warning Decision Making using AWIPS-2 at the University of Oklahoma

    NASA Astrophysics Data System (ADS)

    Zwink, A. B.; Morris, D.; Ware, P. J.; Ernst, S.; Holcomb, B.; Riley, S.; Hardy, J.; Mullens, S.; Bowlan, M.; Payne, C.; Bates, A.; Williams, B.

    2016-12-01

    For several years, employees at the Cooperative Institute of Mesoscale Meteorological Studies at the University of Oklahoma (OU) that are affiliated with Warning Decision Training Division (WDTD) of the National Weather Service (NWS) provided training simulations to students from OU's School of Meteorology (SoM). These simulations focused on warning decision making using Dual-Pol radar data products in an AWIPS-1 environment. Building on these previous experiences, CIMMS/WDTD recently continued the collaboration with the SoM Oklahoma Weather Lab (OWL) by holding a warning decision workshop simulating a NWS Weather Forecast Office (WFO) experience. The workshop took place in the WDTD AWIPS-2 computer laboratory with 25 AWIPS-2 workstations and the WES-2 Bridge (Weather Event Simulator) software which replayed AWIPS-2 data. Using the WES-2 Bridge and the WESSL-2 (WES Scripting Language) event display, this computer lab has the state-of-the-art ability to simulate severe weather events and recreate WFO warning operations. OWL Student forecasters attending the workshop worked in teams in a multi-player simulation of the Hastings, Nebraska WFO on May 6th, 2015, where thunderstorms across the service area produced large hail, damaging winds, and multiple tornadoes. This paper will discuss the design and goals of the WDTD/OWL workshop, as well as plans for holding similar workshops in the future.

  9. Voltage-gated proton channel in a dinoflagellate

    PubMed Central

    Smith, Susan M. E.; Morgan, Deri; Musset, Boris; Cherny, Vladimir V.; Place, Allen R.; Hastings, J. Woodland; DeCoursey, Thomas E.

    2011-01-01

    Fogel and Hastings first hypothesized the existence of voltage-gated proton channels in 1972 in bioluminescent dinoflagellates, where they were thought to trigger the flash by activating luciferase. Proton channel genes were subsequently identified in human, mouse, and Ciona intestinalis, but their existence in dinoflagellates remained unconfirmed. We identified a candidate proton channel gene from a Karlodinium veneficum cDNA library based on homology with known proton channel genes. K. veneficum is a predatory, nonbioluminescent dinoflagellate that produces toxins responsible for fish kills worldwide. Patch clamp studies on the heterologously expressed gene confirm that it codes for a genuine voltage-gated proton channel, kHV1: it is proton-specific and activated by depolarization, its gH–V relationship shifts with changes in external or internal pH, and mutation of the selectivity filter (which we identify as Asp51) results in loss of proton-specific conduction. Indirect evidence suggests that kHV1 is monomeric, unlike other proton channels. Furthermore, kHV1 differs from all known proton channels in activating well negative to the Nernst potential for protons, EH. This unique voltage dependence makes the dinoflagellate proton channel ideally suited to mediate the proton influx postulated to trigger bioluminescence. In contrast to vertebrate proton channels, whose main function is acid extrusion, we propose that proton channels in dinoflagellates have fundamentally different functions of signaling and excitability. PMID:22006335

  10. Land subsidence caused by withdrawal of oil and gas in the Gulf coastal plain - The Houston, Texas, case history

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holzer, T.L.

    1990-09-01

    The extensive network of geodetic leveling lines in the Houston-Galveston, Texas, area, where at least 110 oil and gas fields have been developed, provides the most comprehensive opportunity in the Gulf Coast to search for the occurrence of land subsidence caused by withdrawal of oil and gas. Although the evaluation is complicated by regional subsidence caused by a decline of ground-water level in aquifers beneath the area, subsidence caused by oil and gas withdrawal can be examined by searching for local increases of subsidence at oil and gas fields crossed by leveling lines. Twenty-nine fields are crossed by lines withmore » repeated leveling surveys. Subsidence profiles across these fields indicate local increases of subsidence at six fields-Alco-Mag, Chocolate Bayou, Goose Creek, Hastings, Mykawa, and South Houston. Although ground-water withdrawal is undoubtedly the most important factor contributing to the total subsidence at each field, oil and gas withdrawal may be partly responsible for the local increases. Except for Chocolate Bayou, the volume of petroleum production at each field was sufficient to account for the increase. The volume of petroleum production, however, in general is not a reliable index for predicting the local increase because land within many fields with significant production did not show local increases of subsidence. With the exception of the 1 m subsidence caused by petroleum withdrawal at Goose Creek (1917-1925), local increases of subsidence were less than 0.3 m.« less

  11. Improving the Fitness of High-Dimensional Biomechanical Models via Data-Driven Stochastic Exploration

    PubMed Central

    Bustamante, Carlos D.; Valero-Cuevas, Francisco J.

    2010-01-01

    The field of complex biomechanical modeling has begun to rely on Monte Carlo techniques to investigate the effects of parameter variability and measurement uncertainty on model outputs, search for optimal parameter combinations, and define model limitations. However, advanced stochastic methods to perform data-driven explorations, such as Markov chain Monte Carlo (MCMC), become necessary as the number of model parameters increases. Here, we demonstrate the feasibility and, what to our knowledge is, the first use of an MCMC approach to improve the fitness of realistically large biomechanical models. We used a Metropolis–Hastings algorithm to search increasingly complex parameter landscapes (3, 8, 24, and 36 dimensions) to uncover underlying distributions of anatomical parameters of a “truth model” of the human thumb on the basis of simulated kinematic data (thumbnail location, orientation, and linear and angular velocities) polluted by zero-mean, uncorrelated multivariate Gaussian “measurement noise.” Driven by these data, ten Markov chains searched each model parameter space for the subspace that best fit the data (posterior distribution). As expected, the convergence time increased, more local minima were found, and marginal distributions broadened as the parameter space complexity increased. In the 36-D scenario, some chains found local minima but the majority of chains converged to the true posterior distribution (confirmed using a cross-validation dataset), thus demonstrating the feasibility and utility of these methods for realistically large biomechanical problems. PMID:19272906

  12. CITRATE 1.0: Phytoplankton continuous trait-distribution model with one-dimensional physical transport applied to the North Pacific

    NASA Astrophysics Data System (ADS)

    Chen, Bingzhang; Smith, Sherwood Lan

    2018-02-01

    Diversity plays critical roles in ecosystem functioning, but it remains challenging to model phytoplankton diversity in order to better understand those roles and reproduce consistently observed diversity patterns in the ocean. In contrast to the typical approach of resolving distinct species or functional groups, we present a ContInuous TRAiT-basEd phytoplankton model (CITRATE) that focuses on macroscopic system properties such as total biomass, mean trait values, and trait variance. This phytoplankton component is embedded within a nitrogen-phytoplankton-zooplankton-detritus-iron model that itself is coupled with a simplified one-dimensional ocean model. Size is used as the master trait for phytoplankton. CITRATE also incorporates trait diffusion for sustaining diversity and simple representations of physiological acclimation, i.e., flexible chlorophyll-to-carbon and nitrogen-to-carbon ratios. We have implemented CITRATE at two contrasting stations in the North Pacific where several years of observational data are available. The model is driven by physical forcing including vertical eddy diffusivity imported from three-dimensional general ocean circulation models (GCMs). One common set of model parameters for the two stations is optimized using the Delayed-Rejection Adaptive Metropolis-Hasting Monte Carlo (DRAM) algorithm. The model faithfully reproduces most of the observed patterns and gives robust predictions on phytoplankton mean size and size diversity. CITRATE is suitable for applications in GCMs and constitutes a prototype upon which more sophisticated continuous trait-based models can be developed.

  13. A study on operation efficiency evaluation based on firm's financial index and benchmark selection: take China Unicom as an example

    NASA Astrophysics Data System (ADS)

    Wu, Zu-guang; Tian, Zhan-jun; Liu, Hui; Huang, Rui; Zhu, Guo-hua

    2009-07-01

    Being the only listed telecom operators of A share market, China Unicom has always been attracted many institutional investors under the concept of 3G recent years,which itself is a great technical progress expectation.Do the institutional investors or the concept of technical progress have signficant effect on the improving of firm's operating efficiency?Though reviewing the documentary about operating efficiency we find that schoolars study this problem useing the regress analyzing based on traditional production function and data envelopment analysis(DEA) and financial index anayzing and marginal function and capital labor ratio coefficient etc. All the methods mainly based on macrodata. This paper we use the micro-data of company to evaluate the operating efficiency.Using factor analyzing based on financial index and comparing the factor score of three years from 2005 to 2007, we find that China Unicom's operating efficiency is under the averge level of benchmark corporates and has't improved under the concept of 3G from 2005 to 2007.In other words,institutional investor or the conception of technical progress expectation have faint effect on the changes of China Unicom's operating efficiency. Selecting benchmark corporates as post to evaluate the operating efficiency is a characteristic of this method ,which is basicallly sipmly and direct.This method is suit for the operation efficiency evaluation of agriculture listed companies because agriculture listed also face technical progress and marketing concept such as tax-free etc.

  14. A statistical framework for biomedical literature mining.

    PubMed

    Chung, Dongjun; Lawson, Andrew; Zheng, W Jim

    2017-09-30

    In systems biology, it is of great interest to identify new genes that were not previously reported to be associated with biological pathways related to various functions and diseases. Identification of these new pathway-modulating genes does not only promote understanding of pathway regulation mechanisms but also allow identification of novel targets for therapeutics. Recently, biomedical literature has been considered as a valuable resource to investigate pathway-modulating genes. While the majority of currently available approaches are based on the co-occurrence of genes within an abstract, it has been reported that these approaches show only sub-optimal performances because 70% of abstracts contain information only for a single gene. To overcome such limitation, we propose a novel statistical framework based on the concept of ontology fingerprint that uses gene ontology to extract information from large biomedical literature data. The proposed framework simultaneously identifies pathway-modulating genes and facilitates interpreting functions of these new genes. We also propose a computationally efficient posterior inference procedure based on Metropolis-Hastings within Gibbs sampler for parameter updates and the poor man's reversible jump Markov chain Monte Carlo approach for model selection. We evaluate the proposed statistical framework with simulation studies, experimental validation, and an application to studies of pathway-modulating genes in yeast. The R implementation of the proposed model is currently available at https://dongjunchung.github.io/bayesGO/. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  15. Hormone treatment of children and adolescents with gender dysphoria: an ethical analysis.

    PubMed

    Abel, Brendan S

    2014-09-01

    In the context of transgender health, most people are not comfortable with allowing a twelve-year-old child with gender dysphoria to elect to undergo gender reassignment surgery. The likelihood is too high that the child would be unable to fully comprehend the scope of a decision that carries significant, permanent consequences, particularly because the decision to surgically change gender is based upon a conception of gender that can fluctuate during adolescent years. Conversely, however, most people would not contend that this fluidity is reason to wholly deny certain medical care such as hormonal treatments to transgender youth, a demographic with extremely high rates of violent behavior, self-harm, and suicide. This paper will explore ethical considerations to this emerging debate of what therapeutic options should be offered to transgender children and adolescents. Pediatric endocrinologists have been treating gender dysphoric adolescents with puberty-suppressing drugs and, to a lesser extent, with cross-sex hormone therapies for more than twenty years. Clinicians and thought leaders have mentioned ethical components of this emerging practice in the few cohort studies and clinical review articles about the subject. However, ethics have generally been a secondary consideration in the medical academic literature. In this paper, I will provide a brief overview of the practice, summarize the current research on hormone treatment for transgender minors, and provide an ethical analysis of the practice. © 2014 by The Hastings Center.

  16. 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.

  17. 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.

  18. 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. © 2015 John Wiley & Sons Ltd.

  19. Improving and Evaluating Nested Sampling Algorithm for Marginal Likelihood Estimation

    NASA Astrophysics Data System (ADS)

    Ye, M.; Zeng, X.; Wu, J.; Wang, D.; Liu, J.

    2016-12-01

    With the growing impacts of climate change and human activities on the cycle of water resources, an increasing number of researches focus on the quantification of modeling uncertainty. Bayesian model averaging (BMA) provides a popular framework for quantifying conceptual model and parameter uncertainty. The ensemble prediction is generated by combining each plausible model's prediction, and each model is attached with a model weight which is determined by model's prior weight and marginal likelihood. Thus, the estimation of model's marginal likelihood is crucial for reliable and accurate BMA prediction. Nested sampling estimator (NSE) is a new proposed method for marginal likelihood estimation. The process of NSE is accomplished by searching the parameters' space from low likelihood area to high likelihood area gradually, and this evolution is finished iteratively via local sampling procedure. Thus, the efficiency of NSE is dominated by the strength of local sampling procedure. Currently, Metropolis-Hasting (M-H) algorithm is often used for local sampling. However, M-H is not an efficient sampling algorithm for high-dimensional or complicated parameter space. For improving the efficiency of NSE, it could be ideal to incorporate the robust and efficient sampling algorithm - DREAMzs into the local sampling of NSE. The comparison results demonstrated that the improved NSE could improve the efficiency of marginal likelihood estimation significantly. However, both improved and original NSEs suffer from heavy instability. In addition, the heavy computation cost of huge number of model executions is overcome by using an adaptive sparse grid surrogates.

  20. Searching for Genotype-Phenotype Structure: Using Hierarchical Log-Linear Models in Crohn Disease

    PubMed Central

    Chapman, Juliet M.; Onnie, Clive M.; Prescott, Natalie J.; Fisher, Sheila A.; Mansfield, John C.; Mathew, Christopher G.; Lewis, Cathryn M.; Verzilli, Claudio J.; Whittaker, John C.

    2009-01-01

    There has been considerable recent success in the detection of gene-disease associations. We consider here the development of tools that facilitate the more detailed characterization of the effect of a genetic variant on disease. We replace the simplistic classification of individuals according to a single binary disease indicator with classification according to a number of subphenotypes. This more accurately reflects the underlying biological complexity of the disease process, but it poses additional analytical difficulties. Notably, the subphenotypes that make up a particular disease are typically highly associated, and it becomes difficult to distinguish which genes might be causing which subphenotypes. Such problems arise in many complex diseases. Here, we concentrate on an application to Crohn disease (CD). We consider this problem as one of model selection based upon log-linear models, fitted in a Bayesian framework via reversible-jump Metropolis-Hastings approach. We evaluate the performance of our suggested approach with a simple simulation study and then apply the method to a real data example in CD, revealing a sparse disease structure. Most notably, the associated NOD2.908G→R mutation appears to be directly related to more severe disease behaviors, whereas the other two associated NOD2 variants, 1007L→FS and 702R→W, are more generally related to disease in the small bowel (ileum and jejenum). The ATG16L1.300T→A variant appears to be directly associated with only disease of the small bowel. PMID:19185283

  1. 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.

  2. Sampling algorithms for validation of supervised learning models for Ising-like systems

    NASA Astrophysics Data System (ADS)

    Portman, Nataliya; Tamblyn, Isaac

    2017-12-01

    In this paper, we build and explore supervised learning models of ferromagnetic system behavior, using Monte-Carlo sampling of the spin configuration space generated by the 2D Ising model. Given the enormous size of the space of all possible Ising model realizations, the question arises as to how to choose a reasonable number of samples that will form physically meaningful and non-intersecting training and testing datasets. Here, we propose a sampling technique called ;ID-MH; that uses the Metropolis-Hastings algorithm creating Markov process across energy levels within the predefined configuration subspace. We show that application of this method retains phase transitions in both training and testing datasets and serves the purpose of validation of a machine learning algorithm. For larger lattice dimensions, ID-MH is not feasible as it requires knowledge of the complete configuration space. As such, we develop a new ;block-ID; sampling strategy: it decomposes the given structure into square blocks with lattice dimension N ≤ 5 and uses ID-MH sampling of candidate blocks. Further comparison of the performance of commonly used machine learning methods such as random forests, decision trees, k nearest neighbors and artificial neural networks shows that the PCA-based Decision Tree regressor is the most accurate predictor of magnetizations of the Ising model. For energies, however, the accuracy of prediction is not satisfactory, highlighting the need to consider more algorithmically complex methods (e.g., deep learning).

  3. MRI micturating urethrography for improved urethral delineation in prostate radiotherapy planning: a case study

    NASA Astrophysics Data System (ADS)

    Rai, Robba; Sidhom, Mark; Lim, Karen; Ohanessian, Lucy; Liney, Gary P.

    2017-04-01

    Stereotactic ablative body radiotherapy is used in prostate cancer to deliver a high dose of radiation to the tumour over a small number of treatments. This involves the simulation of the patient using both CT and MRI. Current practice is to insert an indwelling catheter (IDC) during CT to assist with visualisation of the urethra and subsequently minimise dose to this highly critical structure. However, this procedure is invasive and has an associated risk of infection. This is a case study, which demonstrates our initial experience of using a real-time non-invasive MRI technique to replace the use of IDC for prostate cancer patients. The patient was scanned on a dedicated 3T MRI and was instructed to micturate in their own time whereupon a sagittal T2 weighted HASTE sequence was acquired every 5 s. This was subsequently followed by T2 weighted axial imaging at the level of mid prostate to provide improved urethral definition. Acquired images showed bladder voidance in real-time and an increase in signal intensity in the proximal urethra post voiding allowing for delineation of the urethra. The dimension and shape of the proximal urethra was well visualised and accumulation time of urine in the urethra was sufficient to enable optimum timing of the scanning technique. We have presented for the first time a micturating urethography technique using MRI, which has allowed us to visualise the urethra without contrast and with minimal invasiveness to the patient.

  4. Military Genitourinary Trauma: Policies, Implications, and Ethics.

    PubMed

    Dean, Wendy K; Caplan, Arthur L; Parent, Brendan

    2016-11-01

    The men and women who serve in the armed forces, in the words of Major General Joseph Caravalho, "sign a blank check, co-signed by their families, payable to the Army, Navy, Air Force, or Marines, up to and including their lives." It is human nature to consider such a pact in polarized terms; the pact concludes in either a celebratory homecoming or funereal mourning. But in reality, surviving catastrophic injury may incur the greatest debt. The small but real possibility of losing the ability to bear biological children due to genitourinary combat injury has been a topic of discussion in hushed tones, behind closed doors. But as policy changes move the conversation into the open, we must be fully aware of the far-reaching and long-term impacts of decisions on those who have sustained genitourinary injury. In January 2016, Secretary of Defense Ashton Carter outlined a set of reforms that would improve the quality of life for military families by recognizing the importance of maintaining fertility, even in the face of severe injury. This first promising step could build a solid foundation of insuring fertility preservation for wounded service members with genitourinary injury, and it could set a precedent beyond the military for insuring treatment for people who have lost their reproductive capacity. Thus, the ethical challenges raised by the new policy require careful analysis. © 2016 The Hastings Center.

  5. Local and regional smokefree and tobacco-free action in New Zealand: highlights and directions.

    PubMed

    Thomson, George; Wilson, Nick

    2017-09-22

    In this viewpoint we highlight and discuss some recent local and regional level advances in tobacco control in Aotearoa/New Zealand. In this country a wide range of local actors are helping drive smokefree and tobacco-free policies, with an increasing presence of businesses in this field. There has been progress in the areas of smokefree dining, large outdoor worksites and ski fields, and parts of downtown areas such as squares and streets. In 2015 and 2016, three councils (Palmerston North, Napier and Hastings) have used pavement lease policies and bylaws to start introducing an element of requirement into smokefree outdoor dining. Elsewhere (eg, Rotorua, Ashburton, Westland and Christchurch) significant smokefree outdoor dining moves have been made by, or in conjunction with, local councils. Tobacco-free retailing continues to expand, particularly in Northland. In the absence of meaningful central government action on smokefree places in the last decade (despite the Smokefree 2025 goal), local activity is leading the way. It is particularly important in providing models for smokefree outdoor hospitality areas, where smoking normalisation and relapse are significant health risks. Nevertheless, there is a need for the local smokefree and tobacco-free activity to be nationally evaluated, particularly for assessing the prevalence of smoking in areas covered by 'smokefree' policies. Action by central government could help local actors by providing a more definite legislative basis for bylaws, by minimum outdoor smokefree laws and by the funding of effective tobacco control mass media.

  6. Saline as the Sole Contrast Agent for Successful MRI-guided Epidural Injections

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deli, Martin, E-mail: martin.deli@web.de; Fritz, Jan, E-mail: jfritz9@jhmi.edu; Mateiescu, Serban, E-mail: mateiescu@microtherapy.de

    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 withmore » 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.« less

  7. Institutional Ethics Resources: Creating Moral Spaces.

    PubMed

    Hamric, Ann B; Wocial, Lucia D

    2016-09-01

    Since 1992, institutions accredited by The Joint Commission have been required to have a process in place that allows staff members, patients, and families to address ethical issues or issues prone to conflict. While the commission's expectations clearly have made ethics committees more common, simply having a committee in no way demonstrates its effectiveness in terms of the availability of the service to key constituents, the quality of the processes used, or the outcomes achieved. Beyond meeting baseline accreditation standards, effective ethics resources are requisite for quality care for another reason. The provision of care to the sick is a practice with profound moral dimensions. Clinicians need what Margaret Urban Walker has called "moral spaces," reflective spaces within institutions in which to explore and communicate values and ethical obligations as they undergird goals of care. Walker proposed that ethicists needed to be concerned with the design and maintenance of these moral spaces. Clearly, that concern needs to extend beyond ethicists to institutional leaders. This essay uses Walker's idea of moral space to describe individuals and groups who are actual and potential ethics resources in health care institutions. We focus on four requisite characteristics of effective resources and the challenges to achieving them, and we identify strategies to build them. In our view, such moral spaces are particularly important for nurses and their colleagues on interprofessional teams and need to be expanded and strengthened in most settings. © 2016 The Hastings Center.

  8. Commercial air travel and in-flight pulmonary hypertension.

    PubMed

    Smith, Thomas G; Chang, Rae W; Robbins, Peter A; Dorrington, Keith L

    2013-01-01

    It has recently been shown that commercial air travel triggers hypoxic pulmonary vasoconstriction and modestly increases pulmonary artery pressure in healthy passengers. There is large interindividual variation in hypoxic pulmonary vasoreactivity, and some passengers may be at risk of developing flight-induced pulmonary hypertension, with potentially dangerous consequences. This study sought to determine whether it is possible for a susceptible passenger to develop pulmonary hypertension in response to a routine commercial flight. Using in-flight echocardiography, a passenger was studied during a 6-h commercial flight from London to Dubai. The passenger was generally well and frequently traveled by air, but had been diagnosed with Chuvash polycythemia, a genetic condition that is associated with increased hypoxic pulmonary vasoreactivity. Hematocrit had been normalized with regular venesection. During the flight, arterial oxygen saturation fell to a minimum of 96% and systolic pulmonary artery pressure (sPAP) rapidly increased into the pulmonary hypertensive range. The in-flight increase in sPAP was 50%, reaching a peak of 45 mmHg. This study has established that an asymptomatic but susceptible passenger can rapidly develop in-flight pulmonary hypertension even during a medium-haul flight. Prospective passengers at risk from such responses, including those who have cardiopulmonary disease or increased hypoxic pulmonary vasoreactivity, could benefit from preflight evaluation with a hypoxia altitude simulation test combined with simultaneous echocardiography (HAST-echo). The use of in-flight supplementary oxygen should be considered for susceptible individuals, including all patients diagnosed with Chuvash polycythemia.

  9. 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

  10. GRID-BASED EXPLORATION OF COSMOLOGICAL PARAMETER SPACE WITH SNAKE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mikkelsen, K.; Næss, S. K.; Eriksen, H. K., E-mail: kristin.mikkelsen@astro.uio.no

    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)more » 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.« less

  11. Ethical Principles, Process, and the Work of Bioethics Commissions.

    PubMed

    Sulmasy, Daniel P

    2017-05-01

    Shortly after the Presidential Commission for the Study of Bioethical Issues was constituted in 2010 and days before the commission members were to join a conference call to discuss possible topics for their deliberation, Craig Venter held a press conference announcing that his lab had created a synthetic chromosome for a species of mycoplasma and had inserted this genetic material into organisms of another species of mycoplasma (the genes of which had been deactivated), transforming the host species into the donor species. While not overtly claiming to have "created life in the test tube," Venter's publicity seemed cleverly designed to provoke the media into reporting his discovery in just that way. The resulting uproar caused President Obama to give his new bioethics commission the assignment of investigating the ethics of the emerging field of synthetic biology. The commission went right to work. It formed working groups to deliberate about parts of the report, feeding ideas and language to the staff members who would do the actual writing, and then present the working group suggestions to the commission as a whole for public deliberation at open meetings. One of those working groups was charged with coming up with ethical principles that would guide the analysis. Having served as a member of that working group, I report here on the process by which these principles emerged and reflect upon the suitability of that process for the work of public bioethics commissions. © 2017 The Hastings Center.

  12. Development and comparison of Bayesian modularization method in uncertainty assessment of hydrological models

    NASA Astrophysics Data System (ADS)

    Li, L.; Xu, C.-Y.; Engeland, K.

    2012-04-01

    With respect to model calibration, parameter estimation and analysis of uncertainty sources, different approaches have been used in hydrological models. Bayesian method is one of the most widely used methods for uncertainty assessment of hydrological models, which incorporates different sources of information into a single analysis through Bayesian theorem. However, none of these applications can well treat the uncertainty in extreme flows of hydrological models' simulations. This study proposes a Bayesian modularization method approach in uncertainty assessment of conceptual hydrological models by considering the extreme flows. It includes a comprehensive comparison and evaluation of uncertainty assessments by a new Bayesian modularization method approach and traditional Bayesian models using the Metropolis Hasting (MH) algorithm with the daily hydrological model WASMOD. Three likelihood functions are used in combination with traditional Bayesian: the AR (1) plus Normal and time period independent model (Model 1), the AR (1) plus Normal and time period dependent model (Model 2) and the AR (1) plus multi-normal model (Model 3). The results reveal that (1) the simulations derived from Bayesian modularization method are more accurate with the highest Nash-Sutcliffe efficiency value, and (2) the Bayesian modularization method performs best in uncertainty estimates of entire flows and in terms of the application and computational efficiency. The study thus introduces a new approach for reducing the extreme flow's effect on the discharge uncertainty assessment of hydrological models via Bayesian. Keywords: extreme flow, uncertainty assessment, Bayesian modularization, hydrological model, WASMOD

  13. Development and comparison in uncertainty assessment based Bayesian modularization method in hydrological modeling

    NASA Astrophysics Data System (ADS)

    Li, Lu; Xu, Chong-Yu; Engeland, Kolbjørn

    2013-04-01

    SummaryWith respect to model calibration, parameter estimation and analysis of uncertainty sources, various regression and probabilistic approaches are used in hydrological modeling. A family of Bayesian methods, which incorporates different sources of information into a single analysis through Bayes' theorem, is widely used for uncertainty assessment. However, none of these approaches can well treat the impact of high flows in hydrological modeling. This study proposes a Bayesian modularization uncertainty assessment approach in which the highest streamflow observations are treated as suspect information that should not influence the inference of the main bulk of the model parameters. This study includes a comprehensive comparison and evaluation of uncertainty assessments by our new Bayesian modularization method and standard Bayesian methods using the Metropolis-Hastings (MH) algorithm with the daily hydrological model WASMOD. Three likelihood functions were used in combination with standard Bayesian method: the AR(1) plus Normal model independent of time (Model 1), the AR(1) plus Normal model dependent on time (Model 2) and the AR(1) plus Multi-normal model (Model 3). The results reveal that the Bayesian modularization method provides the most accurate streamflow estimates measured by the Nash-Sutcliffe efficiency and provide the best in uncertainty estimates for low, medium and entire flows compared to standard Bayesian methods. The study thus provides a new approach for reducing the impact of high flows on the discharge uncertainty assessment of hydrological models via Bayesian method.

  14. 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.

  15. Cosmographic analysis with Chebyshev polynomials

    NASA Astrophysics Data System (ADS)

    Capozziello, Salvatore; D'Agostino, Rocco; Luongo, Orlando

    2018-05-01

    The limits of standard cosmography are here revised addressing the problem of error propagation during statistical analyses. To do so, we propose the use of Chebyshev polynomials to parametrize cosmic distances. In particular, we demonstrate that building up rational Chebyshev polynomials significantly reduces error propagations with respect to standard Taylor series. This technique provides unbiased estimations of the cosmographic parameters and performs significatively better than previous numerical approximations. To figure this out, we compare rational Chebyshev polynomials with Padé series. In addition, we theoretically evaluate the convergence radius of (1,1) Chebyshev rational polynomial and we compare it with the convergence radii of Taylor and Padé approximations. We thus focus on regions in which convergence of Chebyshev rational functions is better than standard approaches. With this recipe, as high-redshift data are employed, rational Chebyshev polynomials remain highly stable and enable one to derive highly accurate analytical approximations of Hubble's rate in terms of the cosmographic series. Finally, we check our theoretical predictions by setting bounds on cosmographic parameters through Monte Carlo integration techniques, based on the Metropolis-Hastings algorithm. We apply our technique to high-redshift cosmic data, using the Joint Light-curve Analysis supernovae sample and the most recent versions of Hubble parameter and baryon acoustic oscillation measurements. We find that cosmography with Taylor series fails to be predictive with the aforementioned data sets, while turns out to be much more stable using the Chebyshev approach.

  16. 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.

  17. Estimating rare events in biochemical systems using conditional sampling.

    PubMed

    Sundar, V S

    2017-01-28

    The paper focuses on development of variance reduction strategies to estimate rare events in biochemical systems. Obtaining this probability using brute force Monte Carlo simulations in conjunction with the stochastic simulation algorithm (Gillespie's method) is computationally prohibitive. To circumvent this, important sampling tools such as the weighted stochastic simulation algorithm and the doubly weighted stochastic simulation algorithm have been proposed. However, these strategies require an additional step of determining the important region to sample from, which is not straightforward for most of the problems. In this paper, we apply the subset simulation method, developed as a variance reduction tool in the context of structural engineering, to the problem of rare event estimation in biochemical systems. The main idea is that the rare event probability is expressed as a product of more frequent conditional probabilities. These conditional probabilities are estimated with high accuracy using Monte Carlo simulations, specifically the Markov chain Monte Carlo method with the modified Metropolis-Hastings algorithm. Generating sample realizations of the state vector using the stochastic simulation algorithm is viewed as mapping the discrete-state continuous-time random process to the standard normal random variable vector. This viewpoint opens up the possibility of applying more sophisticated and efficient sampling schemes developed elsewhere to problems in stochastic chemical kinetics. The results obtained using the subset simulation method are compared with existing variance reduction strategies for a few benchmark problems, and a satisfactory improvement in computational time is demonstrated.

  18. 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.

  19. Are Antimalarial Hybrid Molecules a Close Reality or a Distant Dream?

    PubMed

    Agarwal, Drishti; Gupta, Rinkoo D; Awasthi, Satish K

    2017-05-01

    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 toward finding alternative chemotherapeutic agents that are capable of combating multidrug-resistant parasite strains. In light of this situation, scientists have come up with the concept of hybridization of two or more active pharmacophores into a single chemical entity, resulting in "antimalarial hybrids." The approach has been applied widely for generation of lead compounds against deadly diseases such as cancer and AIDS, with a proven potential for use 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 the 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 realized. A number of questions left unaddressed at present need to be answered before this approach can progress 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 on the shortcomings that are surfacing as more and more studies on molecular hybridization of the active pharmacophores of known antimalarials are being published. Copyright © 2017 American Society for Microbiology.

  20. Just a Collection of Recollections: Clinical Ethics Consultation and the Interplay of Evaluating Voices.

    PubMed

    Bartlett, Virginia L; Bliton, Mark J; Finder, Stuart G

    2016-12-01

    Despite increased attention to the question of how best to evaluate clinical ethics consultations and emphasis on external evaluation (Hastings Center Report, ASBH Quality Attestation Process), there has been little sustained focus on how we, as clinicians, make sense of and learn from our own experiences in the midst of any one consultation. Questions of how we evaluate the request for, unfolding of, and conclusion of any specific ethics consultation are often overlooked, along with the underlying question of whether it is possible to give an accurate account of clinical ethics consultants' experience as experienced by ethics consultants. Before the challenge of submitting one's accounts or case reports for review and evaluation from others (at one's local institution or in the broader field), there is an underlying challenge of understanding and evaluating our own accounts. To highlight this crucial and deeply challenging dimension of actual clinical ethics practice, we present an account of a complex consultation, explicitly constructed to engage the reader in the unfolding experience of the consultant by emphasizing the multiple perspectives unfolding within the consultant's experience. Written in script format, the three perspectives presented-prototypical clinically descriptive account; didactically reflective and self-evidentiary account often seen in journal presentations; highly self-critical reflective account emphasizing uncertainties inherent to clinical ethics practice-reflect different manners for responding to the ways actual clinical involvement in ethics consultation practice accentuates and refocuses the question of how to understand and evaluate our own work, as well as that of our colleagues.

  1. Bayesian Atmospheric Radiative Transfer (BART): Model, Statistics Driver, and Application to HD 209458b

    NASA Astrophysics Data System (ADS)

    Cubillos, Patricio; Harrington, Joseph; Blecic, Jasmina; Stemm, Madison M.; Lust, Nate B.; Foster, Andrew S.; Rojo, Patricio M.; Loredo, Thomas J.

    2014-11-01

    Multi-wavelength secondary-eclipse and transit depths probe the thermo-chemical properties of exoplanets. In recent years, several research groups have developed retrieval codes to analyze the existing data and study the prospects of future facilities. However, the scientific community has limited access to these packages. Here we premiere the open-source Bayesian Atmospheric Radiative Transfer (BART) code. We discuss the key aspects of the radiative-transfer algorithm and the statistical package. The radiation code includes line databases for all HITRAN molecules, high-temperature H2O, TiO, and VO, and includes a preprocessor for adding additional line databases without recompiling the radiation code. Collision-induced absorption lines are available for H2-H2 and H2-He. The parameterized thermal and molecular abundance profiles can be modified arbitrarily without recompilation. The generated spectra are integrated over arbitrary bandpasses for comparison to data. BART's statistical package, Multi-core Markov-chain Monte Carlo (MC3), is a general-purpose MCMC module. MC3 implements the Differental-evolution Markov-chain Monte Carlo algorithm (ter Braak 2006, 2009). MC3 converges 20-400 times faster than the usual Metropolis-Hastings MCMC algorithm, and in addition uses the Message Passing Interface (MPI) to parallelize the MCMC chains. We apply the BART retrieval code to the HD 209458b data set to estimate the planet's temperature profile and molecular abundances. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

  2. 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.

  3. Nudge or Grudge? Choice Architecture and Parental Decision-Making.

    PubMed

    Blumenthal-Barby, Jennifer; Opel, Douglas J

    2018-03-01

    Richard Thaler and Cass Sunstein define a nudge as "any aspect of the choice architecture that alters people's behavior in a predictable way without forbidding any options or significantly changing their economic incentives." Much has been written about the ethics of nudging competent adult patients. Less has been written about the ethics of nudging surrogates' decision-making and how the ethical considerations and arguments in that context might differ. Even less has been written about nudging surrogate decision-making in the context of pediatrics, despite fundamental differences that exist between the pediatric and adult contexts. Yet, as the field of behavioral economics matures and its insights become more established and well-known, nudges will become more crafted, sophisticated, intentional, and targeted. Thus, the time is now for reflection and ethical analysis regarding the appropriateness of nudges in pediatrics. We argue that there is an even stronger ethical justification for nudging in parental decision-making than with competent adult patients deciding for themselves. We give three main reasons in support of this: (1) child patients do not have autonomy that can be violated (a concern with some nudges), and nudging need not violate parental decision-making authority; (2) nudging can help fulfill pediatric clinicians' obligations to ensure parental decisions are in the child's interests, particularly in contexts where there is high certainty that a recommended intervention is low risk and of high benefit; and (3) nudging can relieve parents' decisional burden regarding what is best for their child, particularly with decisions that have implications for public health. © 2018 The Hastings Center.

  4. The Different Moral Bases of Patient and Surrogate Decision-Making.

    PubMed

    Brudney, Daniel

    2018-01-01

    My topic is a problem with our practice of surrogate decision-making in health care, namely, the problem of the surrogate who is not doing her job-the surrogate who cannot be reached or the surrogate who seems to refuse to understand or to be unable to understand the clinical situation. The analysis raises a question about the surrogate who simply disagrees with the medical team. One might think that such a surrogate is doing her job-the team just doesn't like how she is doing it. My analysis raises the question of whether (or perhaps when) she should be overridden. In approaching this problem, I focus not on the range of difficulties in practice but on the underlying moral conceptual issue. My concern will be to show that the moral values that underpin patient decision-making are fundamentally different from those that underpin surrogate decision-making. Identifying the distinctions will set parameters for any successful solution to the "Who should decide?" A patient has a specific kind of moral right to make her own medical decisions. A surrogate has no analogous moral right to decide for someone else. We want the surrogate to make the decision because we believe that she has a relevant epistemological advantage over anyone else on the scene. If and when she has no such advantage or if she refuses or is unable to use it, then there might not be sufficient reason to let her be the decision-maker. © 2018 The Hastings Center.

  5. Behavioral Economics and the Public Acceptance of Synthetic Biology.

    PubMed

    Oliver, Adam

    2018-01-01

    Different applications of synthetic biology are alike in that their possible negative consequences are highly uncertain, potentially catastrophic, and perhaps irreversible; therefore, they are also alike in that public attitudes about them are fertile ground for behavioral economic phenomena. Findings from behavioral economics suggest that people may not respond to such applications according to the normal rules of economic evaluation, by which the value of an outcome is multiplied by the mathematical probability that the outcome will occur. Possibly, then, synthetic biology applications challenge the normative postulates of the standard approach, too. I want to first consider how some of the phenomena described by behavioral economists-and behavioral scientists more broadly-might affect people's perceptions of the uncertainties associated with synthetic biology. My analysis will be far from complete, however, because behavioral economics is essentially the study of human behavior, and thus its reach is potentially vast and its development longstanding and ongoing. Nonetheless, I hope to give an indicative perspective on how some aspects of behavioral economics might affect the assessment and perceived acceptability of synthetic biology. I will then consider the issue of agency. Should policy-makers respect people's reactions to synthetic biology when those reactions are known to be driven by behavioral economic phenomena rather than following the normative postulates of rational choice theory? Or should policy-makers dismiss these reactions as inherently biased? I will argue that the normative force of these human reactions (probably) depends on phenomenon and context. © 2018 The Hastings Center.

  6. Ascertainment correction for Markov chain Monte Carlo segregation and linkage analysis of a quantitative trait.

    PubMed

    Ma, Jianzhong; Amos, Christopher I; Warwick Daw, E

    2007-09-01

    Although extended pedigrees are often sampled through probands with extreme levels of a quantitative trait, Markov chain Monte Carlo (MCMC) methods for segregation and linkage analysis have not been able to perform ascertainment corrections. Further, the extent to which ascertainment of pedigrees leads to biases in the estimation of segregation and linkage parameters has not been previously studied for MCMC procedures. In this paper, we studied these issues with a Bayesian MCMC approach for joint segregation and linkage analysis, as implemented in the package Loki. We first simulated pedigrees ascertained through individuals with extreme values of a quantitative trait in spirit of the sequential sampling theory of Cannings and Thompson [Cannings and Thompson [1977] Clin. Genet. 12:208-212]. Using our simulated data, we detected no bias in estimates of the trait locus location. However, in addition to allele frequencies, when the ascertainment threshold was higher than or close to the true value of the highest genotypic mean, bias was also found in the estimation of this parameter. When there were multiple trait loci, this bias destroyed the additivity of the effects of the trait loci, and caused biases in the estimation all genotypic means when a purely additive model was used for analyzing the data. To account for pedigree ascertainment with sequential sampling, we developed a Bayesian ascertainment approach and implemented Metropolis-Hastings updates in the MCMC samplers used in Loki. Ascertainment correction greatly reduced biases in parameter estimates. Our method is designed for multiple, but a fixed number of trait loci. Copyright (c) 2007 Wiley-Liss, Inc.

  7. Bayesian inference in an item response theory model with a generalized student t link function

    NASA Astrophysics Data System (ADS)

    Azevedo, Caio L. N.; Migon, Helio S.

    2012-10-01

    In this paper we introduce a new item response theory (IRT) model with a generalized Student t-link function with unknown degrees of freedom (df), named generalized t-link (GtL) IRT model. In this model we consider only the difficulty parameter in the item response function. GtL is an alternative to the two parameter logit and probit models, since the degrees of freedom (df) play a similar role to the discrimination parameter. However, the behavior of the curves of the GtL is different from those of the two parameter models and the usual Student t link, since in GtL the curve obtained from different df's can cross the probit curves in more than one latent trait level. The GtL model has similar proprieties to the generalized linear mixed models, such as the existence of sufficient statistics and easy parameter interpretation. Also, many techniques of parameter estimation, model fit assessment and residual analysis developed for that models can be used for the GtL model. We develop fully Bayesian estimation and model fit assessment tools through a Metropolis-Hastings step within Gibbs sampling algorithm. We consider a prior sensitivity choice concerning the degrees of freedom. The simulation study indicates that the algorithm recovers all parameters properly. In addition, some Bayesian model fit assessment tools are considered. Finally, a real data set is analyzed using our approach and other usual models. The results indicate that our model fits the data better than the two parameter models.

  8. Assessment of Flood Disaster Impacts in Cambodia: Implications for Rapid Disaster Response

    NASA Astrophysics Data System (ADS)

    Ahamed, Aakash; Bolten, John; Doyle, Colin

    2016-04-01

    Disaster monitoring systems can provide near real time estimates of population and infrastructure affected by sudden onset natural hazards. This information is useful to decision makers allocating lifesaving resources following disaster events. Floods are the world's most common and devastating disasters (UN, 2004; Doocy et al., 2013), and are particularly frequent and severe in the developing countries of Southeast Asia (Long and Trong, 2001; Jonkman, 2005; Kahn, 2005; Stromberg, 2007; Kirsch et al., 2012). Climate change, a strong regional monsoon, and widespread hydropower construction contribute to a complex and unpredictable regional hydrodynamic regime. As such, there is a critical need for novel techniques to assess flood impacts to population and infrastructure with haste during and following flood events in order to enable governments and agencies to optimize response efforts following disasters. Here, we build on methods to determine regional flood extent in near real time and develop systems that automatically quantify the socioeconomic impacts of flooding in Cambodia. Software developed on cloud based, distributed processing Geographic Information Systems (GIS) is used to demonstrate spatial and numerical estimates of population, households, roadways, schools, hospitals, airports, agriculture and fish catch affected by severe monsoon flooding occurring in the Cambodian portion of Lower Mekong River Basin in 2011. Results show modest agreement with government and agency estimates. Maps and statistics generated from the system are intended to complement on the ground efforts and bridge information gaps to decision makers. The system is open source, flexible, and can be applied to other disasters (e.g. earthquakes, droughts, landslides) in various geographic regions.

  9. An introduction of Markov chain Monte Carlo method to geochemical inverse problems: Reading melting parameters from REE abundances in abyssal peridotites

    NASA Astrophysics Data System (ADS)

    Liu, Boda; Liang, Yan

    2017-04-01

    Markov chain Monte Carlo (MCMC) simulation is a powerful statistical method in solving inverse problems that arise from a wide range of applications. In Earth sciences applications of MCMC simulations are primarily in the field of geophysics. The purpose of this study is to introduce MCMC methods to geochemical inverse problems related to trace element fractionation during mantle melting. MCMC methods have several advantages over least squares methods in deciphering melting processes from trace element abundances in basalts and mantle rocks. Here we use an MCMC method to invert for extent of melting, fraction of melt present during melting, and extent of chemical disequilibrium between the melt and residual solid from REE abundances in clinopyroxene in abyssal peridotites from Mid-Atlantic Ridge, Central Indian Ridge, Southwest Indian Ridge, Lena Trough, and American-Antarctic Ridge. We consider two melting models: one with exact analytical solution and the other without. We solve the latter numerically in a chain of melting models according to the Metropolis-Hastings algorithm. The probability distribution of inverted melting parameters depends on assumptions of the physical model, knowledge of mantle source composition, and constraints from the REE data. Results from MCMC inversion are consistent with and provide more reliable uncertainty estimates than results based on nonlinear least squares inversion. We show that chemical disequilibrium is likely to play an important role in fractionating LREE in residual peridotites during partial melting beneath mid-ocean ridge spreading centers. MCMC simulation is well suited for more complicated but physically more realistic melting problems that do not have analytical solutions.

  10. A comparison of two techniques for knee arthrodesis: the custom made intramedullary Mayday nail versus a monoaxial external fixator.

    PubMed

    Yeoh, David; Goddard, Richard; Macnamara, Paul; Bowman, Nicholas; Miles, Kim; East, Debra; Butler-Manuel, Adrian

    2008-08-01

    The most common indication for knee arthrodesis is pain and instability in an unreconstructable knee following an infected knee arthroplasty. In this study, we compare the use of the Mayday arthrodesis nail (Orthodynamics, Christchurch, UK) versus external fixation, Orthofix (Berkshire UK) and Stryker Hoffman II (County Cork, Ireland). All patients in this study underwent arthrodesis between 1995 and 2006 at Conquest Hospital, Hastings. In group A, 11 patients underwent arthrodesis with a Mayday nail. In all cases, the indications were infected total knee replacements (TKR). Three of these patients previously had failed attempts at arthrodesis with external fixation devices. In group B, seven patients underwent arthrodesis using external fixation. In six patients, the indication was infected TKRs. Results were reviewed retrospectively, with union assessed both clinically and radiologically. The mean inpatient stay for the Mayday nail group was 23 days (range 8-45 days) compared with 76 days (range 34-122) for the external fixation group (p<0.01, CI 95). Ten patients in group A went on to confirmed primary arthrodesis. One patient underwent revision arthrodesis with a Mayday nail and subsequently united. In group B only two patients achieved union. The rate of union was significantly greater in the Mayday nail group than the external fixation group (91% vs 29%, p<0.01). Of those patients that achieved union, there was no difference in the time to fusion between groups. Our study supported the existing literature and found that the Mayday nail appeared more effective than monoaxial external fixators for arthrodesis in the management of infected total knee replacements.

  11. A methodology to determine boundary conditions from forced convection experiments using liquid crystal thermography

    NASA Astrophysics Data System (ADS)

    Jakkareddy, Pradeep S.; Balaji, C.

    2017-02-01

    This paper reports the results of an experimental study to estimate the heat flux and convective heat transfer coefficient using liquid crystal thermography and Bayesian inference in a heat generating sphere, enclosed in a cubical Teflon block. The geometry considered for the experiments comprises a heater inserted in a hollow hemispherical aluminium ball, resulting in a volumetric heat generation source that is placed at the center of the Teflon block. Calibrated thermochromic liquid crystal sheets are used to capture the temperature distribution at the front face of the Teflon block. The forward model is the three dimensional conduction equation which is solved within the Teflon block to obtain steady state temperatures, using COMSOL. Match up experiments are carried out for various velocities by minimizing the residual between TLC and simulated temperatures for every assumed loss coefficient, to obtain a correlation of average Nusselt number against Reynolds number. This is used for prescribing the boundary condition for the solution to the forward model. A surrogate model obtained by artificial neural network built upon the data from COMSOL simulations is used to drive a Markov Chain Monte Carlo based Metropolis Hastings algorithm to generate the samples. Bayesian inference is adopted to solve the inverse problem for determination of heat flux and heat transfer coefficient from the measured temperature field. Point estimates of the posterior like the mean, maximum a posteriori and standard deviation of the retrieved heat flux and convective heat transfer coefficient are reported. Additionally the effect of number of samples on the performance of the estimation process has been investigated.

  12. A gradient-based model parametrization using Bernstein polynomials in Bayesian inversion of surface wave dispersion

    NASA Astrophysics Data System (ADS)

    Gosselin, Jeremy M.; Dosso, Stan E.; Cassidy, John F.; Quijano, Jorge E.; Molnar, Sheri; Dettmer, Jan

    2017-10-01

    This paper develops and applies a Bernstein-polynomial parametrization to efficiently represent general, gradient-based profiles in nonlinear geophysical inversion, with application to ambient-noise Rayleigh-wave dispersion data. Bernstein polynomials provide a stable parametrization in that small perturbations to the model parameters (basis-function coefficients) result in only small perturbations to the geophysical parameter profile. A fully nonlinear Bayesian inversion methodology is applied to estimate shear wave velocity (VS) profiles and uncertainties from surface wave dispersion data extracted from ambient seismic noise. The Bayesian information criterion is used to determine the appropriate polynomial order consistent with the resolving power of the data. Data error correlations are accounted for in the inversion using a parametric autoregressive model. The inversion solution is defined in terms of marginal posterior probability profiles for VS as a function of depth, estimated using Metropolis-Hastings sampling with parallel tempering. This methodology is applied to synthetic dispersion data as well as data processed from passive array recordings collected on the Fraser River Delta in British Columbia, Canada. Results from this work are in good agreement with previous studies, as well as with co-located invasive measurements. The approach considered here is better suited than `layered' modelling approaches in applications where smooth gradients in geophysical parameters are expected, such as soil/sediment profiles. Further, the Bernstein polynomial representation is more general than smooth models based on a fixed choice of gradient type (e.g. power-law gradient) because the form of the gradient is determined objectively by the data, rather than by a subjective parametrization choice.

  13. Pulmonary artery pressure increases during commercial air travel in healthy passengers.

    PubMed

    Smith, Thomas G; Talbot, Nick P; Chang, Rae W; Wilkinson, Elizabeth; Nickol, Annabel H; Newman, David G; Robbins, Peter A; Dorrington, Keith L

    2012-07-01

    It is not known whether the mild hypoxia experienced by passengers during commercial air travel triggers hypoxic pulmonary vasoconstriction and increases pulmonary artery pressure in flight. Insidious pulmonary hypertensive responses could endanger susceptible passengers who have cardiopulmonary disease or increased hypoxic pulmonary vascular sensitivity. Understanding these effects may improve pre-flight assessment of fitness-to-fly and reduce in-flight morbidity and mortality. Eight healthy volunteers were studied during a scheduled commercial airline flight from London, UK, to Denver, CO. The aircraft was a Boeing 777 and the duration of the flight was 9 h. Systolic pulmonary artery pressure (sPAP) was assessed by portable Doppler echocardiography during the flight and over the following week in Denver, where the altitude (5280 ft/1610 m) simulates a commercial airliner environment. Cruising cabin altitude ranged between 5840 and 7170 ft (1780 to 2185 m), and mean arterial oxygen saturation was 95 +/- 0.6% during the flight. Mean sPAP increased significantly in flight by 6 +/- 1 mmHg to 33 +/- 1 mmHg, an increase of approximately 20%. After landing in Denver, sPAP was still 3 +/- 1 mmHg higher than baseline and remained elevated at 30 +/- 1 mmHg for a further 12 h. Pulmonary artery pressure increases during commercial air travel in healthy passengers, raising the possibility that hypoxic pulmonary hypertension could develop in susceptible individuals. A hypoxia altitude simulation test with simultaneous echocardiography ('HAST-echo') may be beneficial in assessing fitness to fly in vulnerable patients.

  14. Justifying Clinical Nudges.

    PubMed

    Gorin, Moti; Joffe, Steven; Dickert, Neal; Halpern, Scott

    2017-03-01

    The shift away from paternalistic decision-making and toward patient-centered, shared decision-making has stemmed from the recognition that in order to practice medicine ethically, health care professionals must take seriously the values and preferences of their patients. At the same time, there is growing recognition that minor and seemingly irrelevant features of how choices are presented can substantially influence the decisions people make. Behavioral economists have identified striking ways in which trivial differences in the presentation of options can powerfully and predictably affect people's choices. Choice-affecting features of the decision environment that do not restrict the range of choices or significantly alter the incentives have come to be known as "nudges." Although some have criticized conscious efforts to influence choice, we believe that clinical nudges may often be morally justified. The most straightforward justification for nudge interventions is that they help people bypass their cognitive limitations-for example, the tendency to choose the first option presented even when that option is not the best for them-thereby allowing people to make choices that best align with their rational preferences or deeply held values. However, we argue that this justification is problematic. We argue that, if physicians wish to use nudges to shape their patients' choices, the justification for doing so must appeal to an ethical and professional standard, not to patients' preferences. We demonstrate how a standard with which clinicians and bioethicists already are quite familiar-the best-interest standard-offers a robust justification for the use of nudges. © 2017 The Hastings Center.

  15. On Patient Well-being and Professional Authority.

    PubMed

    Solomon, Mildred Z

    2017-01-01

    Two papers in this issue address the limits of surrogates' authority when making life-and-death decisions for dying family members or friends. Using palliative sedation as an example, Jeffrey Berger offers a conceptual argument for bounding surrogate authority. Since freedom from pain is an essential interest, when imminently dying, cognitively incapacitated patients are in duress and their symptoms are not manageable in any other way, clinicians should be free to offer palliative sedation without surrogate consent, although assent should be sought and every effort made to work with surrogates as harmoniously as possible. Ellen Robinson and her colleagues report on the implementation of a policy at Massachusetts General Hospital that supports do-not-resuscitate orders when cardiopulmonary resuscitation is likely to be ineffective or harmful, even if surrogates disagree. The "Doing No Harm" policy at MGH allows for what MGH calls a "medically indicated DNR" and what in some other places is called "a unilateral DNR"-the writing of an order not to provide cardiopulmonary resuscitation, regardless of surrogate disapproval. These kinds of DNR policies have emerged in some hospitals across the country and for much the same reason that Berger provides in his argument regarding palliative sedation. I support the reasoning and the policies in both the Berger and Robinson papers. However, as the authors would most likely agree, the problems they aim to remedy are not simply about the scope of surrogate and professional authority. They are also symptoms of inattention to professional obligations and system failures. © 2017 The Hastings Center.

  16. Fostering Nurses' Moral Agency and Moral Identity: The Importance of Moral Community.

    PubMed

    Liaschenko, Joan; Peter, Elizabeth

    2016-09-01

    It may be the case that the most challenging moral problem of the twenty-first century will be the relationship between the individual moral agent and the practices and institutions in which the moral agent is embedded. In this paper, we continue the efforts that one of us, Joan Liaschenko, first called for in 1993, that of using feminist ethics as a lens for viewing the relationship between individual nurses as moral agents and the highly complex institutions in which they do the work of nursing. Feminist ethics, with its emphasis on the inextricable relationship between ethics and politics, provides a useful lens to understand the work of nurses in context. Using Margaret Urban Walker's and Hilde Lindemann's concepts of identity, relationships, values, and moral agency, we argue that health care institutions can be moral communities and profoundly affect the work and identity and, therefore, the moral agency of all who work within those structures, including nurses. Nurses are not only shaped by these organizations but also have the power to shape them. Because moral agency is intimately connected to one's identity, moral identity work is essential for nurses to exercise their moral agency and to foster moral community in health care organizations. We first provide a brief history of nursing's morally problematic relationship with institutions and examine the impact institutional master narratives and corporatism exert today on nurses' moral identities and agency. We close by emphasizing the significance of ongoing dialogue in creating and sustaining moral communities, repairing moral identities, and strengthening moral agency. © 2016 The Hastings Center.

  17. How international is bioethics? A quantitative retrospective study.

    PubMed

    Borry, Pascal; Schotsmans, Paul; Dierickx, Kris

    2006-01-13

    Studying the contribution of individual countries to leading journals in a specific discipline can highlight which countries have the most impact on that discipline and whether a geographic bias exists. This article aims to examine the international distribution of publications in the field of bioethics. Retrospective quantitative study of nine peer reviewed journals in the field of bioethics and medical ethics (Bioethics, Cambridge Quarterly of Healthcare Ethics, Hastings Center Report, Journal of Clinical Ethics, Journal of Medical Ethics, Kennedy Institute of Ethics Journal, Nursing Ethics, Christian Bioethics, and Theoretical Medicine and Bioethics). In total, 4,029 articles published between 1990 and 2003 were retrieved from the nine bioethical journals under study. The United States (59.3%, n = 2390), the United Kingdom (13.5%, n = 544), Canada (4%, n = 160) and Australia (3.8%, n = 154) had the highest number of publications in terms of absolute number of publications. When normalized to population size, smaller affluent countries, such as New Zealand, Finland and Sweden were more productive than the United States. The number of studies originating from the USA was decreasing in the period between 1990 and 2003. While a lot of peer reviewed journals in the field of bioethics profile themselves as international journals, they certainly do not live up to what one would expect from an "international" journal. The fact that English speaking countries, and to a larger extent American authors, dominate the international journals in the field of bioethics is a clear geographic bias towards the bioethical discussions that are going on in these journals.

  18. Stress In An Oncologist's Life: Present But Not Insurmountable : (Students Should Not Be Discouraged Choosing Oncology as Their Future Specialisation).

    PubMed

    Nowakowski, Jonatan; Borowiec, Grazyna; Zwierz, Izabela; Jagodzinski, Wojciech; Tarkowski, Radoslaw

    2017-03-01

    Burnout is a serious problem facing the majority of oncologists. Many medical students may regard oncology as depressive part of medicine. This false picture may discourage them from choosing oncology as their future specialization. To learn problems experienced by oncologists and to answer the students' question: is it dangerous to choose oncology? We conducted an anonymous survey among 69 oncologists. Young doctors (up to 5 years of service) accounted for 31 %, specialists 69 %, with a median length of practice of 14 years. The most frequently reported symptoms included irritability (84 %) and tension (74 %). Forty-five percent reported headaches, 25 % sleep disorders, 51 % negative impact on their personal lives. Excessive bureaucratization, overwork, and haste, with the disparity between undertaken effort and compensation were the most common sources of stress. Stress reduction methods were as follows: their relationship with family and/or friends (69 %), reading books/watching movies (66 %), emotional distance from their problems (63 %), and contact with nature (62 %). Ninety-six percent of physicians were satisfied with their choice of pursuing work with cancer patients. However, as many as 49 % of oncologists experienced moments of doubt regarding their sense of vocation. Students and young doctors considering pursuing an oncological speciality should not be discouraged by the likely degree of sacrifice or burden, but rather aim to develop effective ways to reduce stress, along with remembering one's own health needs. This could be valuable part of both pregradual and postgradual medical education, worth to become part of medical curricula.

  19. Consequences of workplace bullying with respect to the well-being of its targets and the observers of bullying.

    PubMed

    Vartia, M A

    2001-02-01

    This study investigated the effects of workplace bullying and the psychological work environment on the well-being and subjective stress of the targets and observers of bullying. In a questionnaire study, stress and psychological ill-health were measured, and the causes of reported stress were analyzed for municipal employees (N=949, 85% women, 15% men, mean age 41 years for the men and 40 years for the women). Both the targets of bullying and the observers reported more general stress and mental stress reactions than did respondents from the workplaces with no bullying. The targets also expressed feelings of low self-confidence more often than did those who had not been subjected to bullying. Being bullied, but also features of one's work, especially haste, excessively difficult tasks and poor goal clarity, predicted the stress reactions reported. Of the single forms of bullying, judging a person's work unjustly or in an offending manner, restricting a person's possibilities to express his or her opinions, and assaulting one's private life were the most clearly connected with all the stress reactions measured. Victim history was associated with feelings of low self-confidence. The targets of bullying used sleep-inducing drugs and sedatives more often than did the respondents who were not bullied. The study shows that not only the targets of bullying, but also bystanders, suffer when someone is bullied in the workplace. Bullying must therefore be regarded as a problem for the entire work unit and not merely as a problem of the target.

  20. Increased persistence via asynchrony in oscillating ecological populations with long-range interaction

    NASA Astrophysics Data System (ADS)

    Gupta, Anubhav; Banerjee, Tanmoy; Dutta, Partha Sharathi

    2017-10-01

    Understanding the influence of the structure of a dispersal network on the species persistence and modeling a realistic species dispersal in nature are two central issues in spatial ecology. A realistic dispersal structure which favors the persistence of interacting ecological systems was studied [M. D. Holland and A. Hastings, Nature (London) 456, 792 (2008), 10.1038/nature07395], where it was shown that a randomization of the structure of a dispersal network in a metapopulation model of prey and predator increases the species persistence via clustering, prolonged transient dynamics, and amplitudes of population fluctuations. In this paper, by contrast, we show that a deterministic network topology in a metapopulation can also favor asynchrony and prolonged transient dynamics if species dispersal obeys a long-range interaction governed by a distance-dependent power law. To explore the effects of power-law coupling, we take a realistic ecological model, namely, the Rosenzweig-MacArthur model in each patch (node) of the network of oscillators, and show that the coupled system is driven from synchrony to asynchrony with an increase in the power-law exponent. Moreover, to understand the relationship between species persistence and variations in power-law exponent, we compute a correlation coefficient to characterize cluster formation, a synchrony order parameter, and median predator amplitude. We further show that smaller metapopulations with fewer patches are more vulnerable to extinction as compared to larger metapopulations with a higher number of patches. We believe that the present work improves our understanding of the interconnection between the random network and the deterministic network in theoretical ecology.

  1. Reconceptualizing Autonomy: A Relational Turn in Bioethics.

    PubMed

    Jennings, Bruce

    2016-05-01

    History's judgment on the success of bioethics will not depend solely on the conceptual creativity and innovation in the field at the level of ethical and political theory, but this intellectual work is not insignificant. One important new development is what I shall refer to as the relational turn in bioethics. This development represents a renewed emphasis on the ideographic approach, which interprets the meaning of right and wrong in human actions as they are inscribed in social and cultural practices and in structures of lived meaning and interdependence; in an ideographic approach, the task of bioethics is to bring practice into theory, not the other way around. The relational turn in bioethics may profoundly affect the critical questions that the field asks and the ethical guidance it offers society, politics, and policy. The relational turn provides a way of correcting the excessive atomism of many individualistic perspectives that have been, and continue to be, influential in bioethics. Nonetheless, I would argue that most of the work reflecting the relational turn remains distinctively liberal in its respect for the ethical significance of the human individual. It moves away from individualism, but not from the value of individuality.In this review essay, I shall focus on how the relational turn has manifested itself in work on core concepts in bioethics, especially liberty and autonomy. Following a general review, I conclude with a brief consideration of two important recent books in this area: Jennifer Nedelsky's Law's Relations and Rachel Haliburton's Autonomy and the Situated Self. © 2016 The Hastings Center.

  2. Estimation of spatially varying heat transfer coefficient from a flat plate with flush mounted heat sources using Bayesian inference

    NASA Astrophysics Data System (ADS)

    Jakkareddy, Pradeep S.; Balaji, C.

    2016-09-01

    This paper employs the Bayesian based Metropolis Hasting - Markov Chain Monte Carlo algorithm to solve inverse heat transfer problem of determining the spatially varying heat transfer coefficient from a flat plate with flush mounted discrete heat sources with measured temperatures at the bottom of the plate. The Nusselt number is assumed to be of the form Nu = aReb(x/l)c . To input reasonable values of ’a’ and ‘b’ into the inverse problem, first limited two dimensional conjugate convection simulations were done with Comsol. Based on the guidance from this different values of ‘a’ and ‘b’ are input to a computationally less complex problem of conjugate conduction in the flat plate (15mm thickness) and temperature distributions at the bottom of the plate which is a more convenient location for measuring the temperatures without disturbing the flow were obtained. Since the goal of this work is to demonstrate the eficiacy of the Bayesian approach to accurately retrieve ‘a’ and ‘b’, numerically generated temperatures with known values of ‘a’ and ‘b’ are treated as ‘surrogate’ experimental data. The inverse problem is then solved by repeatedly using the forward solutions together with the MH-MCMC aprroach. To speed up the estimation, the forward model is replaced by an artificial neural network. The mean, maximum-a-posteriori and standard deviation of the estimated parameters ‘a’ and ‘b’ are reported. The robustness of the proposed method is examined, by synthetically adding noise to the temperatures.

  3. Are Antimalarial Hybrid Molecules a Close Reality or a Distant Dream?

    PubMed Central

    Agarwal, Drishti; Gupta, Rinkoo D.

    2017-01-01

    ABSTRACT 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 toward finding alternative chemotherapeutic agents that are capable of combating multidrug-resistant parasite strains. In light of this situation, scientists have come up with the concept of hybridization of two or more active pharmacophores into a single chemical entity, resulting in “antimalarial hybrids.” The approach has been applied widely for generation of lead compounds against deadly diseases such as cancer and AIDS, with a proven potential for use 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 the 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 realized. A number of questions left unaddressed at present need to be answered before this approach can progress 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 on the shortcomings that are surfacing as more and more studies on molecular hybridization of the active pharmacophores of known antimalarials are being published. PMID:28289029

  4. Uncertainty in dual permeability model parameters for structured soils.

    PubMed

    Arora, B; Mohanty, B P; McGuire, J T

    2012-01-01

    Successful application of dual permeability models (DPM) to predict contaminant transport is contingent upon measured or inversely estimated soil hydraulic and solute transport parameters. The difficulty in unique identification of parameters for the additional macropore- and matrix-macropore interface regions, and knowledge about requisite experimental data for DPM has not been resolved to date. Therefore, this study quantifies uncertainty in dual permeability model parameters of experimental soil columns with different macropore distributions (single macropore, and low- and high-density multiple macropores). Uncertainty evaluation is conducted using adaptive Markov chain Monte Carlo (AMCMC) and conventional Metropolis-Hastings (MH) algorithms while assuming 10 out of 17 parameters to be uncertain or random. Results indicate that AMCMC resolves parameter correlations and exhibits fast convergence for all DPM parameters while MH displays large posterior correlations for various parameters. This study demonstrates that the choice of parameter sampling algorithms is paramount in obtaining unique DPM parameters when information on covariance structure is lacking, or else additional information on parameter correlations must be supplied to resolve the problem of equifinality of DPM parameters. This study also highlights the placement and significance of matrix-macropore interface in flow experiments of soil columns with different macropore densities. Histograms for certain soil hydraulic parameters display tri-modal characteristics implying that macropores are drained first followed by the interface region and then by pores of the matrix domain in drainage experiments. Results indicate that hydraulic properties and behavior of the matrix-macropore interface is not only a function of saturated hydraulic conductivity of the macroporematrix interface ( K sa ) and macropore tortuosity ( l f ) but also of other parameters of the matrix and macropore domains.

  5. Reliability testing of two classification systems for osteoarthritis and post-traumatic arthritis of the elbow.

    PubMed

    Amini, Michael H; Sykes, Joshua B; Olson, Stephen T; Smith, Richard A; Mauck, Benjamin M; Azar, Frederick M; Throckmorton, Thomas W

    2015-03-01

    The severity of elbow arthritis is one of many factors that surgeons must evaluate when considering treatment options for a given patient. Elbow surgeons have historically used the Broberg and Morrey (BM) and Hastings and Rettig (HR) classification systems to radiographically stage the severity of post-traumatic arthritis (PTA) and primary osteoarthritis (OA). We proposed to compare the intraobserver and interobserver reliability between systems for patients with either PTA or OA. The radiographs of 45 patients were evaluated at least 2 weeks apart by 6 evaluators of different levels of training. Intraobserver and interobserver reliability were calculated by Spearman correlation coefficients with 95% confidence intervals. Agreement was considered almost perfect for coefficients >0.80 and substantial for coefficients of 0.61 to 0.80. In patients with both PTA and OA, intraobserver reliability and interobserver reliability were substantial, with no difference between classification systems. There were no significant differences in intraobserver or interobserver reliability between attending physicians and trainees for either classification system (all P > .10). The presence of fracture implants did not affect reliability in the BM system but did substantially worsen reliability in the HR system (intraobserver P = .04 and interobserver P = .001). The BM and HR classifications both showed substantial intraobserver and interobserver reliability for PTA and OA. Training level differences did not affect reliability for either system. Both trainees and fellowship-trained surgeons may easily and reliably apply each classification system to the evaluation of primary elbow OA and PTA, although the HR system was less reliable in the presence of fracture implants. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  6. Quasiparticle explanation of the weak-thermalization regime under quench in a nonintegrable quantum spin chain

    NASA Astrophysics Data System (ADS)

    Lin, Cheng-Ju; Motrunich, Olexei I.

    2017-02-01

    The eigenstate thermalization hypothesis provides one picture of thermalization in a quantum system by looking at individual eigenstates. However, it is also important to consider how local observables reach equilibrium values dynamically. Quench protocol is one of the settings to study such questions. A recent numerical study [Bañuls, Cirac, and Hastings, Phys. Rev. Lett. 106, 050405 (2007), 10.1103/PhysRevLett.106.050405] of a nonintegrable quantum Ising model with longitudinal field under such a quench setting found different behaviors for different initial quantum states. One particular case called the "weak-thermalization" regime showed apparently persistent oscillations of some observables. Here we provide an explanation of such oscillations. We note that the corresponding initial state has low energy density relative to the ground state of the model. We then use perturbation theory near the ground state and identify the oscillation frequency as essentially a quasiparticle gap. With this quasiparticle picture, we can then address the long-time behavior of the oscillations. Upon making additional approximations which intuitively should only make thermalization weaker, we argue that the oscillations nevertheless decay in the long-time limit. As part of our arguments, we also consider a quench from a BEC to a hard-core boson model in one dimension. We find that the expectation value of a single-boson creation operator oscillates but decays exponentially in time, while a pair-boson creation operator has oscillations with a t-3 /2 decay in time. We also study dependence of the decay time on the density of bosons in the low-density regime and use this to estimate decay time for oscillations in the original spin model.

  7. Sexual health risks and health-seeking behaviours among substance-misusing women.

    PubMed

    Edelman, Natalie Lois; Patel, Harish; Glasper, Anthony; Bogen-Johnston, Leanne

    2014-12-01

    To report on a survey of sexual health service needs among substance-misusing women attending a substance misuse service. Substance-misusing women carry a disproportionate burden of sexual ill health, yet the range and frequency of their sexual health risks, morbidities and service engagement are poorly understood. A cross-sectional survey of a convenience sample of substance-misusing women attending a substance misuse service. From 4 April 2010-17 September 2010, substance-misusing women in Hastings & Ore, UK, were invited to complete a paper questionnaire addressing: drug use; cervical cytology, sexually transmitted infection and HIV screening history; pregnancy history, perceived pregnancy risk and contraceptive advice and supply; sexual activity and assault. Of 91 respondents, 77 attended local drug treatment services - results comprise analysis of this sub-sample. The study sample was characterized by long-term opioid and crack cocaine use. Of 53% sexually active in the previous 4 weeks, 66% perceived they had experienced sexual intercourse that could lead to pregnancy during that time. Fifty-five per cent had been forced to have sex against their will during their lifetime. High rates of sexually transmitted infections, pregnancy termination, miscarriage and abnormal cervical cytology were reported. Findings indicate the need to recognize the breadth of elevated sexual health risks and morbidities experienced by substance-misusing women with long-term opioid/crack use, including those not identifying as intravenous drug users. Poor recall of drop-in and appointment times, reluctance to disclose substance misuse and likelihood of previous sexual assault present significant challenges to nurses, who must take a sensitive, opportunistic approach to referral and provision of sexual health interventions to substance-misusing women. © 2014 John Wiley & Sons Ltd.

  8. An update on the Enzyme Portal: an integrative approach for exploring enzyme knowledge

    PubMed Central

    Onwubiko, J.; Zaru, R.; Rosanoff, S.; Antunes, R.; Bingley, M.; Watkins, X.; O'Donovan, C.; Martin, M. J.

    2017-01-01

    Abstract Enzymes are a key part of life processes and are increasingly important for various areas of research such as medicine, biotechnology, bioprocessing and drug research. The goal of the Enzyme Portal is to provide an interface to all European Bioinformatics Institute (EMBL-EBI) data about enzymes (de Matos, P., et al., (2013), BMC Bioinformatics, 14 (1), 103). These data include enzyme function, sequence features and family classification, protein structure, reactions, pathways, small molecules, diseases and the associated literature. The sources of enzyme data are: the UniProt Knowledgebase (UniProtKB) (UniProt Consortium, 2015), the Protein Data Bank in Europe (PDBe), (Valenkar, S., et al., Nucleic Acids Res.2016; 44, D385–D395) Rhea—a database of enzyme-catalysed reactions (Morgat, A., et al., Nucleic Acids Res. 2015; 43, D459-D464), Reactome—a database of biochemical pathways (Fabregat, A., et al., Nucleic Acids Res. 2016; 44, D481–D487), IntEnz—a resource with enzyme nomenclature information (Fleischmann, A., et al., Nucleic Acids Res. 2004 32, D434–D437) and ChEBI (Hastings, J., et al., Nucleic Acids Res. 2013) and ChEMBL (Bento, A. P., et al., Nucleic Acids Res. 201442, 1083–1090)—resources which contain information about small-molecule chemistry and bioactivity. This article describes the redesign of Enzyme Portal and the increased functionality added to maximise integration and interpretation of these data. Use case examples of the Enzyme Portal and the versatile workflows its supports are illustrated. We welcome the suggestion of new resources for integration. PMID:28158609

  9. Being Right Isn't Always Enough: NFL Culture and Team Physicians' Conflict of Interest.

    PubMed

    McKinney, Ross

    2016-11-01

    The job of being a sports team physician is difficult, regardless of the level, from high school to the National Football League. When a sports league receives the intensity of attention leveled at the NFL, though, a difficult occupation becomes even more challenging. Even for the NFL players themselves, players' best interests regarding health issues are often unclear. Football players are, as a lot, highly competitive individuals. They want to win, and they want to help the team win. It's a warrior culture, and respect is earned by playing hurt. Should the team physician respect a player's autonomy when this means allowing him to make choices that might lead to further personal harm, especially if the player's choices align with the preference of the coach and management? Or should the doctor set limits and balance the player's choices with a paternalistic set of constraints, perhaps in opposition to both the player's and the team's desires? Simplification of this web of conflicts of interest is the goal of the model proposed by Glenn Cohen, Holly Lynch, and Christopher Deubert. In my view, their proposal is very clever. As an idea, it meets the expectations its authors set, namely, to minimize the problem of conflict of interest in the delivery of health care services to NFL football players. The ethics of the proposal align well with certain moral goals, like treating the player's interests more fairly and treating the player's health as an end instead of as the means to an end. But will such a proposal ever make headway in the pressurized environment of the NFL? © 2016 The Hastings Center.

  10. Duality in Phase Space and Complex Dynamics of an Integrated Pest Management Network Model

    NASA Astrophysics Data System (ADS)

    Yuan, Baoyin; Tang, Sanyi; Cheke, Robert A.

    Fragmented habitat patches between which plants and animals can disperse can be modeled as networks with varying degrees of connectivity. A predator-prey model with network structures is proposed for integrated pest management (IPM) with impulsive control actions. The model was analyzed using numerical methods to investigate how factors such as the impulsive period, the releasing constant of natural enemies and the mode of connections between the patches affect pest outbreak patterns and the success or failure of pest control. The concept of the cluster as defined by Holland and Hastings is used to describe variations in results ranging from global synchrony when all patches have identical fluctuations to n-cluster solutions with all patches having different dynamics. Heterogeneity in the initial densities of either pest or natural enemy generally resulted in a variety of cluster oscillations. Surprisingly, if n > 1, the clusters fall into two groups one with low amplitude fluctuations and the other with high amplitude fluctuations (i.e. duality in phase space), implying that control actions radically alter the system's characteristics by inducing duality and more complex dynamics. When the impulsive period is small enough, i.e. the control strategy is undertaken frequently, the pest can be eradicated. As the period increases, the pest's dynamics shift from a steady state to become chaotic with periodic windows and more multicluster oscillations arise for heterogenous initial density distributions. Period-doubling bifurcation and periodic halving cascades occur as the releasing constant of the natural enemy increases. For the same ecological system with five differently connected networks, as the randomness of the connectedness increases, the transient duration becomes smaller and the probability of multicluster oscillations appearing becomes higher.

  11. Progress in legal definition of brain death and consent to remove cadaver organs.

    PubMed

    Stuart, F P

    1977-01-01

    The availability of cadaver kidneys for transplantation falls far short of the needs of a rapidly expanding population of patients on chronic hemodialysis. Kidneys with the least ischemic injury come from donors with fatal head injury or stroke; such kidneys can be removed from a "beating-heart" cadaver after declaring death on the basis of brain death. To clarify the legal status of brain death and to encourage salvage of transplantable kidneys with minimal ischemic injury, 12 states already have codified the concept of brain death. Although the first few laws were lengthy and included medical terms, six of the last seven laws have used one or two models proposed by the American Bar Association (ABA) and the Institute of Society, Ethics and Life Sciences, Hastings-on-Hudson, N. Y. The ABA proposal is the simpler of the two models and should provide the basis for future state laws. In addition, the National Conference of Commissioners on Uniform State Laws plans to present a model law to define death and the liabilities of a physician who declares death on the basis of brain death by mid 1977. While state legislatures have written laws that establish the legality of the concept of brain death, medical groups have sought to define the medical criteria for its determination. The most recent list of criteria comes from a National Institutes of Health-supported Collaborative Study on Cerebral Survival, as follows: (1) unresponsivity, (2) apnea, (3) dilated pupils and absent cephalic reflexes, (4) electrocerebral silence, (5) a confirmatory test of absent cerebral blood flow (angiography, isotope bolus curve, retinoscopy, or echoencephalography).

  12. DNA motif alignment by evolving a population of Markov chains.

    PubMed

    Bi, Chengpeng

    2009-01-30

    Deciphering cis-regulatory elements or de novo motif-finding in genomes still remains elusive although much algorithmic effort has been expended. The Markov chain Monte Carlo (MCMC) method such as Gibbs motif samplers has been widely employed to solve the de novo motif-finding problem through sequence local alignment. Nonetheless, the MCMC-based motif samplers still suffer from local maxima like EM. Therefore, as a prerequisite for finding good local alignments, these motif algorithms are often independently run a multitude of times, but without information exchange between different chains. Hence it would be worth a new algorithm design enabling such information exchange. This paper presents a novel motif-finding algorithm by evolving a population of Markov chains with information exchange (PMC), each of which is initialized as a random alignment and run by the Metropolis-Hastings sampler (MHS). It is progressively updated through a series of local alignments stochastically sampled. Explicitly, the PMC motif algorithm performs stochastic sampling as specified by a population-based proposal distribution rather than individual ones, and adaptively evolves the population as a whole towards a global maximum. The alignment information exchange is accomplished by taking advantage of the pooled motif site distributions. A distinct method for running multiple independent Markov chains (IMC) without information exchange, or dubbed as the IMC motif algorithm, is also devised to compare with its PMC counterpart. Experimental studies demonstrate that the performance could be improved if pooled information were used to run a population of motif samplers. The new PMC algorithm was able to improve the convergence and outperformed other popular algorithms tested using simulated and biological motif sequences.

  13. Uncertainty in dual permeability model parameters for structured soils

    NASA Astrophysics Data System (ADS)

    Arora, B.; Mohanty, B. P.; McGuire, J. T.

    2012-01-01

    Successful application of dual permeability models (DPM) to predict contaminant transport is contingent upon measured or inversely estimated soil hydraulic and solute transport parameters. The difficulty in unique identification of parameters for the additional macropore- and matrix-macropore interface regions, and knowledge about requisite experimental data for DPM has not been resolved to date. Therefore, this study quantifies uncertainty in dual permeability model parameters of experimental soil columns with different macropore distributions (single macropore, and low- and high-density multiple macropores). Uncertainty evaluation is conducted using adaptive Markov chain Monte Carlo (AMCMC) and conventional Metropolis-Hastings (MH) algorithms while assuming 10 out of 17 parameters to be uncertain or random. Results indicate that AMCMC resolves parameter correlations and exhibits fast convergence for all DPM parameters while MH displays large posterior correlations for various parameters. This study demonstrates that the choice of parameter sampling algorithms is paramount in obtaining unique DPM parameters when information on covariance structure is lacking, or else additional information on parameter correlations must be supplied to resolve the problem of equifinality of DPM parameters. This study also highlights the placement and significance of matrix-macropore interface in flow experiments of soil columns with different macropore densities. Histograms for certain soil hydraulic parameters display tri-modal characteristics implying that macropores are drained first followed by the interface region and then by pores of the matrix domain in drainage experiments. Results indicate that hydraulic properties and behavior of the matrix-macropore interface is not only a function of saturated hydraulic conductivity of the macroporematrix interface (Ksa) and macropore tortuosity (lf) but also of other parameters of the matrix and macropore domains.

  14. [Assessment of work environment vs. feeling of threat and aggravation of stress in job of a high risk - An attempt of organizational intervention].

    PubMed

    Stasiła-Sieradzka, Marta; Chudzicka-Czupała, Agata; Grabowski, Damian; Dobrowolska, Małgorzata

    2018-01-01

    The main purpose of this article was to examine, whether and to what extend an assessment of work environment and feeling of threat are associated with stress at work performed in health- and life-threatening conditions. Previous studies of the determinants of occupational stress have been carried out in relation to representatives of different occupational groups that are not, however, representatives of one organization. The research was also meant to provide practical guidance for a particular employer. The study was carried out in the factory of explosives. It involved 95 randomly selected employees of the production departments. Subjective evaluation of work was performed by the examined persons in the Areas of Worklife Survey. It allows to assess the functioning of the employee in the workplace and to recognize the discrepancies between the requirements of the organization and the needs, aspirations and abilities of the examined person. Feeling of insecurity at work was defined by using the Feeling of Danger at Work Survey. The level of stress was assessed using the Perceived Stress Scale (PSS-10). The workload and feeling of danger are relevant to the stress felt by the employees. The workload is also the mediator of the relations between the sense of danger and the stress felt by the examined employees. At the level of manufacturing process management in an organization, there is a need to reduce the negative impact of physical and mental strain associated with haste and uncertainty. Med Pr 2018;69(1):45-58. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  15. An update on the Enzyme Portal: an integrative approach for exploring enzyme knowledge.

    PubMed

    Pundir, S; Onwubiko, J; Zaru, R; Rosanoff, S; Antunes, R; Bingley, M; Watkins, X; O'Donovan, C; Martin, M J

    2017-03-01

    Enzymes are a key part of life processes and are increasingly important for various areas of research such as medicine, biotechnology, bioprocessing and drug research. The goal of the Enzyme Portal is to provide an interface to all European Bioinformatics Institute (EMBL-EBI) data about enzymes (de Matos, P., et al. , (2013), BMC Bioinformatics , (1), 103). These data include enzyme function, sequence features and family classification, protein structure, reactions, pathways, small molecules, diseases and the associated literature. The sources of enzyme data are: the UniProt Knowledgebase (UniProtKB) (UniProt Consortium, 2015), the Protein Data Bank in Europe (PDBe), (Valenkar, S., et al ., Nucleic Acids Res. 2016; , D385-D395) Rhea-a database of enzyme-catalysed reactions (Morgat, A., et al .,  Nucleic Acids Res.  2015; , D459-D464), Reactome-a database of biochemical pathways (Fabregat, A., et al ., Nucleic Acids Res. 2016;  , D481-D487), IntEnz-a resource with enzyme nomenclature information (Fleischmann, A., et al ., Nucleic Acids Res.  2004 , D434-D437) and ChEBI (Hastings, J., et al .,  Nucleic Acids Res. 2013) and ChEMBL (Bento, A. P., et al ., Nucleic Acids Res.  2014 , 1083-1090)-resources which contain information about small-molecule chemistry and bioactivity. This article describes the redesign of Enzyme Portal and the increased functionality added to maximise integration and interpretation of these data. Use case examples of the Enzyme Portal and the versatile workflows its supports are illustrated. We welcome the suggestion of new resources for integration. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  16. Probabilistic Graphical Model Representation in Phylogenetics

    PubMed Central

    Höhna, Sebastian; Heath, Tracy A.; Boussau, Bastien; Landis, Michael J.; Ronquist, Fredrik; Huelsenbeck, John P.

    2014-01-01

    Recent years have seen a rapid expansion of the model space explored in statistical phylogenetics, emphasizing the need for new approaches to statistical model representation and software development. Clear communication and representation of the chosen model is crucial for: (i) reproducibility of an analysis, (ii) model development, and (iii) software design. Moreover, a unified, clear and understandable framework for model representation lowers the barrier for beginners and nonspecialists to grasp complex phylogenetic models, including their assumptions and parameter/variable dependencies. Graphical modeling is a unifying framework that has gained in popularity in the statistical literature in recent years. The core idea is to break complex models into conditionally independent distributions. The strength lies in the comprehensibility, flexibility, and adaptability of this formalism, and the large body of computational work based on it. Graphical models are well-suited to teach statistical models, to facilitate communication among phylogeneticists and in the development of generic software for simulation and statistical inference. Here, we provide an introduction to graphical models for phylogeneticists and extend the standard graphical model representation to the realm of phylogenetics. We introduce a new graphical model component, tree plates, to capture the changing structure of the subgraph corresponding to a phylogenetic tree. We describe a range of phylogenetic models using the graphical model framework and introduce modules to simplify the representation of standard components in large and complex models. Phylogenetic model graphs can be readily used in simulation, maximum likelihood inference, and Bayesian inference using, for example, Metropolis–Hastings or Gibbs sampling of the posterior distribution. [Computation; graphical models; inference; modularization; statistical phylogenetics; tree plate.] PMID:24951559

  17. Nest-site selection in the acorn woodpecker

    USGS Publications Warehouse

    Hooge, P.N.; Stanback, M.T.; Koenig, Walter D.

    1999-01-01

    Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central California prefer to nest in dead limbs in large, dead valley oaks (Quercus lobata) and California sycamores (Platanus racemosa) that are also frequently used as acorn storage trees. Based on 232 nest cavities used over an 18-year period, we tested whether preferred or modal nest-site characters were associated with increased reproductive success (the "nest-site quality" hypothesis). We also examined whether more successful nests were likely to experience more favorable microclimatic conditions or to be less accessible to terrestrial predators. We found only equivocal support for the nest-site quality hypothesis: only 1 of 5 preferred characters and 2 of 10 characters exhibiting a clear modality were correlated with higher reproductive success. All three characteristics of nests known or likely to be associated with a more favorable microclimate, and two of five characteristics likely to render nests less accessible to predators, were correlated with higher reproductive success. These results suggest that nest cavities in this population are built in part to take advantage of favorable microclimatic conditions and, to a lesser extent, to reduce access to predators. However, despite benefits of particular nest characteristics, birds frequently nested in apparently suboptimal cavities. We also found a significant relationship between mean group size and the history of occupancy of particular territories and the probability of nest cavities being built in microclimatically favorable live limbs, suggesting that larger groups residing on more stable territories were better able to construct nests with optimal characteristics. This indicates that there may be demographic, as well as ecological, constraints on nest-site selection in this primary cavity nester.

  18. Bayesian model selection validates a biokinetic model for zirconium processing in humans

    PubMed Central

    2012-01-01

    Background In radiation protection, biokinetic models for zirconium processing are of crucial importance in dose estimation and further risk analysis for humans exposed to this radioactive substance. They provide limiting values of detrimental effects and build the basis for applications in internal dosimetry, the prediction for radioactive zirconium retention in various organs as well as retrospective dosimetry. Multi-compartmental models are the tool of choice for simulating the processing of zirconium. Although easily interpretable, determining the exact compartment structure and interaction mechanisms is generally daunting. In the context of observing the dynamics of multiple compartments, Bayesian methods provide efficient tools for model inference and selection. Results We are the first to apply a Markov chain Monte Carlo approach to compute Bayes factors for the evaluation of two competing models for zirconium processing in the human body after ingestion. Based on in vivo measurements of human plasma and urine levels we were able to show that a recently published model is superior to the standard model of the International Commission on Radiological Protection. The Bayes factors were estimated by means of the numerically stable thermodynamic integration in combination with a recently developed copula-based Metropolis-Hastings sampler. Conclusions In contrast to the standard model the novel model predicts lower accretion of zirconium in bones. This results in lower levels of noxious doses for exposed individuals. Moreover, the Bayesian approach allows for retrospective dose assessment, including credible intervals for the initially ingested zirconium, in a significantly more reliable fashion than previously possible. All methods presented here are readily applicable to many modeling tasks in systems biology. PMID:22863152

  19. MCMC-ODPR: primer design optimization using Markov Chain Monte Carlo sampling.

    PubMed

    Kitchen, James L; Moore, Jonathan D; Palmer, Sarah A; Allaby, Robin G

    2012-11-05

    Next generation sequencing technologies often require numerous primer designs that require good target coverage that can be financially costly. We aimed to develop a system that would implement primer reuse to design degenerate primers that could be designed around SNPs, thus find the fewest necessary primers and the lowest cost whilst maintaining an acceptable coverage and provide a cost effective solution. We have implemented Metropolis-Hastings Markov Chain Monte Carlo for optimizing primer reuse. We call it the Markov Chain Monte Carlo Optimized Degenerate Primer Reuse (MCMC-ODPR) algorithm. After repeating the program 1020 times to assess the variance, an average of 17.14% fewer primers were found to be necessary using MCMC-ODPR for an equivalent coverage without implementing primer reuse. The algorithm was able to reuse primers up to five times. We compared MCMC-ODPR with single sequence primer design programs Primer3 and Primer-BLAST and achieved a lower primer cost per amplicon base covered of 0.21 and 0.19 and 0.18 primer nucleotides on three separate gene sequences, respectively. With multiple sequences, MCMC-ODPR achieved a lower cost per base covered of 0.19 than programs BatchPrimer3 and PAMPS, which achieved 0.25 and 0.64 primer nucleotides, respectively. MCMC-ODPR is a useful tool for designing primers at various melting temperatures at good target coverage. By combining degeneracy with optimal primer reuse the user may increase coverage of sequences amplified by the designed primers at significantly lower costs. Our analyses showed that overall MCMC-ODPR outperformed the other primer-design programs in our study in terms of cost per covered base.

  20. MCMC-ODPR: Primer design optimization using Markov Chain Monte Carlo sampling

    PubMed Central

    2012-01-01

    Background Next generation sequencing technologies often require numerous primer designs that require good target coverage that can be financially costly. We aimed to develop a system that would implement primer reuse to design degenerate primers that could be designed around SNPs, thus find the fewest necessary primers and the lowest cost whilst maintaining an acceptable coverage and provide a cost effective solution. We have implemented Metropolis-Hastings Markov Chain Monte Carlo for optimizing primer reuse. We call it the Markov Chain Monte Carlo Optimized Degenerate Primer Reuse (MCMC-ODPR) algorithm. Results After repeating the program 1020 times to assess the variance, an average of 17.14% fewer primers were found to be necessary using MCMC-ODPR for an equivalent coverage without implementing primer reuse. The algorithm was able to reuse primers up to five times. We compared MCMC-ODPR with single sequence primer design programs Primer3 and Primer-BLAST and achieved a lower primer cost per amplicon base covered of 0.21 and 0.19 and 0.18 primer nucleotides on three separate gene sequences, respectively. With multiple sequences, MCMC-ODPR achieved a lower cost per base covered of 0.19 than programs BatchPrimer3 and PAMPS, which achieved 0.25 and 0.64 primer nucleotides, respectively. Conclusions MCMC-ODPR is a useful tool for designing primers at various melting temperatures at good target coverage. By combining degeneracy with optimal primer reuse the user may increase coverage of sequences amplified by the designed primers at significantly lower costs. Our analyses showed that overall MCMC-ODPR outperformed the other primer-design programs in our study in terms of cost per covered base. PMID:23126469

  1. Ensemble methods for stochastic networks with special reference to the biological clock of Neurospora crassa.

    PubMed

    Caranica, C; Al-Omari, A; Deng, Z; Griffith, J; Nilsen, R; Mao, L; Arnold, J; Schüttler, H-B

    2018-01-01

    A major challenge in systems biology is to infer the parameters of regulatory networks that operate in a noisy environment, such as in a single cell. In a stochastic regime it is hard to distinguish noise from the real signal and to infer the noise contribution to the dynamical behavior. When the genetic network displays oscillatory dynamics, it is even harder to infer the parameters that produce the oscillations. To address this issue we introduce a new estimation method built on a combination of stochastic simulations, mass action kinetics and ensemble network simulations in which we match the average periodogram and phase of the model to that of the data. The method is relatively fast (compared to Metropolis-Hastings Monte Carlo Methods), easy to parallelize, applicable to large oscillatory networks and large (~2000 cells) single cell expression data sets, and it quantifies the noise impact on the observed dynamics. Standard errors of estimated rate coefficients are typically two orders of magnitude smaller than the mean from single cell experiments with on the order of ~1000 cells. We also provide a method to assess the goodness of fit of the stochastic network using the Hilbert phase of single cells. An analysis of phase departures from the null model with no communication between cells is consistent with a hypothesis of Stochastic Resonance describing single cell oscillators. Stochastic Resonance provides a physical mechanism whereby intracellular noise plays a positive role in establishing oscillatory behavior, but may require model parameters, such as rate coefficients, that differ substantially from those extracted at the macroscopic level from measurements on populations of millions of communicating, synchronized cells.

  2. Differences in Ultrasonic Vocalizations between Wild and Laboratory California Mice (Peromyscus californicus)

    PubMed Central

    Kalcounis-Rueppell, Matina C.; Petric, Radmila; Briggs, Jessica R.; Carney, Catherine; Marshall, Matthew M.; Willse, John T.; Rueppell, Olav; Ribble, David O.; Crossland, Janet P.

    2010-01-01

    Background Ultrasonic vocalizations (USVs) emitted by muroid rodents, including laboratory mice and rats, are used as phenotypic markers in behavioral assays and biomedical research. Interpretation of these USVs depends on understanding the significance of USV production by rodents in the wild. However, there has never been a study of muroid rodent ultrasound function in the wild and comparisons of USVs produced by wild and laboratory rodents are lacking to date. Here, we report the first comparison of wild and captive rodent USVs recorded from the same species, Peromyscus californicus. Methodology and Principal Findings We used standard ultrasound recording techniques to measure USVs from California mice in the laboratory (Peromyscus Genetic Stock Center, SC, USA) and the wild (Hastings Natural History Reserve, CA, USA). To determine which California mouse in the wild was vocalizing, we used a remote sensing method that used a 12-microphone acoustic localization array coupled with automated radio telemetry of all resident Peromyscus californicus in the area of the acoustic localization array. California mice in the laboratory and the wild produced the same types of USV motifs. However, wild California mice produced USVs that were 2–8 kHz higher in median frequency and significantly more variable in frequency than laboratory California mice. Significance The similarity in overall form of USVs from wild and laboratory California mice demonstrates that production of USVs by captive Peromyscus is not an artifact of captivity. Our study validates the widespread use of USVs in laboratory rodents as behavioral indicators but highlights that particular characteristics of laboratory USVs may not reflect natural conditions. PMID:20368980

  3. Chemical composition of Texas surface waters, 1949

    USGS Publications Warehouse

    Irelan, Burdge

    1950-01-01

    This report is the fifth the a series of publications by the Texas Board of Water Engineers giving chemical analyses of the surface waters in the State of Texas. The samples for which data are given were collected between October 1, 1948 and September 30, 1949. During the water year 25 daily sampling stations were maintained by the Geological Survey. Sampled were collected less frequently during the year at many other points. Quality of water records for previous years can be found in the following reports: "Chemical Composition of Texas Surface Waters, 1938-1945," by W. W. Hastings, and J. H. Rowley; "Chemical Composition of Texas Surface Waters, 1946," by W. W. Hastings and B. Irelan; "Chemical Composition of Texas Surface Waters, 1947," by B. Irelan and J. R. Avrett; "Chemical Composition of Texas Surface Waters, 1948," by B. Irelan, D. E. Weaver, and J. R. Avrett. These reports may be obtained from the Texas Board of Water Engineers and Geological Survey at Austin, Texas. Samples for chemical analysis were collected daily at or near points on streams where gaging stations are maintained for measurement of discharge. Most of the analyses were made of 10-day composites of daily samples collected for a year at each sampling point. Three composite samples were usually prepared each month by mixing together equal quantities of daily samples collected for the 1st to the 10th, from the 11th to the 20th, and during the remainder of the month. Monthly composites were made at a few stations where variation in daily conductance was small. For some streams that are subject to sudden large changes in chemical composition, composite samples were made for shorter periods on the basis of the concentration of dissolved solids as indicated by measurement of specific conductance of the daily samples. The mean discharge for the composite period is reported in second-feet. Specific conductance values are expressed as "micromhos, K x 10 at 25° C." Silica, calcium, magnesium, sodium

  4. Molecular regulation of aluminum resistance and sulfur nutrition during root growth.

    PubMed

    Alarcón-Poblete, Edith; Inostroza-Blancheteau, Claudio; Alberdi, Miren; Rengel, Zed; Reyes-Díaz, Marjorie

    2018-01-01

    Aluminum toxicity and sulfate deprivation both regulate microRNA395 expression, repressing its low-affinity sulfate transporter ( SULTR2;1 ) target. Sulfate deprivation also induces the high-affinity sulfate transporter gene ( SULTR12 ), allowing enhanced sulfate uptake. Few studies about the relationships between sulfate, a plant nutrient, and aluminum, a toxic ion, are available; hence, the molecular and physiological processes underpinning this interaction are poorly understood. The Al-sulfate interaction occurs in acidic soils, whereby relatively high concentrations of trivalent toxic aluminum (Al 3+ ) may hamper root growth, limiting uptake of nutrients, including sulfur (S). On the other side, Al 3+ may be detoxified by complexation with sulfate in the acid soil solution as well as in the root-cell vacuoles. In this review, we focus on recent insights into the mechanisms governing plant responses to Al toxicity and its relationship with sulfur nutrition, emphasizing the role of phytohormones, microRNAs, and ion transporters in higher plants. It is known that Al 3+ disturbs gene expression and enzymes involved in biosynthesis of S-containing cysteine in root cells. On the other hand, Al 3+ may induce ethylene biosynthesis, enhance reactive oxygen species production, alter phytohormone transport, trigger root growth inhibition and promote sulfate uptake under S deficiency. MicroRNA395, regulated by both Al toxicity and sulfate deprivation, represses its low-affinity Sulfate Transporter 2;1 (SULTR2;1) target. In addition, sulfate deprivation induces High Affinity Sulfate Transporters (HAST; SULTR1;2), improving sulfate uptake from low-sulfate soil solutions. Identification of new microRNAs and cloning of their target genes are necessary for a better understanding of the role of molecular regulation of plant resistance to Al stress and sulfate deprivation.

  5. Anthropogenic Sulphur Dioxide Load over China as Observed from Different Satellite Sensors

    NASA Technical Reports Server (NTRS)

    Koukouli, M. E.; Balis, D. S.; Johannes Van Der A, Ronald; Theys, N.; Hedelt, P.; Richter, A.; Krotkov, N.; Li, Can; Taylor, M.

    2016-01-01

    China, with its rapid economic growth and immense exporting power, has been the focus of many studies during this previous decade quantifying its increasing emissions contribution to the Earth's atmosphere. With a population slowly shifting towards enlarged power and purchasing needs, the ceaseless inauguration of new power plants, smelters, refineries and industrial parks leads infallibly to increases in sulphur dioxide, SO2, emissions. The recent capability of next generation algorithms as well as new space-borne instruments to detect anthropogenic SO2 loads has enabled a fast advancement in this field. In the following work, algorithms providing total SO2 columns over China based on SCIAMACHY/Envisat, OMI/Aura and GOME2/MetopA observations are presented. The need for post-processing and gridding of the SO2 fields is further revealed in this work, following the path of previous publications. Further, it is demonstrated that the usage of appropriate statistical tools permits studying parts of the datasets typically excluded, such as the winter months loads. Focusing on actual point sources, such as megacities and known power plant locations, instead of entire provinces, monthly mean time series have been examined in detail. The sharp decline in SO2 emissions in more than 90% - 95% of the locations studied confirms the recent implementation of government desulphurisation legislation; however, locations with increases, even for the previous five years, are also identified. These belong to provinces with emerging economies which are in haste to install power plants and are possibly viewed leniently by the authorities, in favour of growth. The SO2 load seasonality has also been examined in detail with a novel mathematical tool, with 70% of the point sources having a statistically significant annual cycle with highs in winter and lows in summer, following the heating requirements of the Chinese population.

  6. An Argument for Fewer Clinical Trials.

    PubMed

    Borgerson, Kirstin

    2016-11-01

    The volume of clinical research is increasing exponentially-far beyond our ability to process and absorb the results. Given this situation, it may be beneficial to consider reducing the flow at its source. In what follows, I will motivate and critically evaluate the following proposal: researchers should conduct fewer clinical trials. More specifically, I c onsider whether researchers should be permitted to conduct only clinical research of very high quality and, in turn, whether research ethics committees (RECs) should prohibit all other, lower-quality research, even when it might appear to meet some minimal ethical standard. Following a close analysis of the social-value requirement of ethical clinical research, I argue that this proposal is defensible. The problem identified in this paper has two parts, quantity and quality, and some clarification is needed about the latter because "quality" is a highly contested term in the medical literature. When some scholars advocate for high-quality trials, they mean large-scale, simple, explanatory randomized controlled trials. Others, including myself, have defended a different characterization of high-quality research that tends more toward pragmatic trial design and the use of methods other than RCTs. Pragmatic trials aim to provide evidence that directly supports clinical decision-making in "usual" care settings. Unlike explanatory trials, which aim to abstract away from particular settings and patients, in the hopes of creating ideal conditions for the success of an intervention, pragmatic trials deliberately pursue knowledge of high applicability, through the use of representative subjects, clinically important questions, flexible treatment protocols, patient-oriented outcome measures, and so on. I see applicability as a marker of high-quality research. The context in which research is meant to be applied should be the context in which new interventions are evaluated. © 2016 The Hastings Center.

  7. What Pacemakers Can Teach Us about the Ethics of Maintaining Artificial Organs.

    PubMed

    Hutchison, Katrina; Sparrow, Robert

    2016-11-01

    One day soon it may be possible to replace a failing heart, liver, or kidney with a long-lasting mechanical replacement or perhaps even with a 3-D printed version based on the patient's own tissue. Such artificial organs could make transplant waiting lists and immunosuppression a thing of the past. Supposing that this happens, what will the ongoing care of people with these implants involve? In particular, how will the need to maintain the functioning of artificial organs over an extended period affect patients and their doctors and the responsibilities of those who manufacture such devices? Drawing on lessons from the history of the cardiac pacemaker, this article offers an initial survey of the ethical issues posed by the need to maintain and service artificial organs. We briefly outline the nature and history of cardiac pacemakers, with a particular focus on the need for technical support, maintenance, and replacement of these devices. Drawing on the existing medical literature and on our conversations and correspondence with cardiologists, regulators, and manufacturers, we describe five sources of ethical issues associated with pacemaker maintenance: the location of the devices inside the human body, such that maintenance generates surgical risks; the complexity of the devices, which increases the risk of harms to patients as well as introducing potential injustices in access to treatment; the role of software-particularly software that can be remotely accessed-in the functioning of the devices, which generates privacy and security issues; the impact of continual development and improvement of the device; and the influence of commercial interests in the context of a medical device market in which there are several competing products. Finally, we offer some initial suggestions as to how these questions should be answered. © 2016 The Hastings Center.

  8. Study of model of anesthesia related adverse event by incident report at King Chulalongkorn Memorial Hospital.

    PubMed

    Narasethkamol, Arunchai; Charuluxananan, Somrat; Kyokong, Oranuch; Premsamran, Porntep; Kundej, Sarawut

    2011-01-01

    As a site of the Thai Anesthesia Incidents Monitoring Study (Thai AIMS), the authors continued data collection of incident reports to find out the frequency, clinical course, contributing factors, factors minimizing adverse events, and investigation of model appropriate for possible corrective strategies in a Thai university hospital. A standardized anesthesia incident report form that included close-end and open-end questions was provided to the attending anesthesia personnel of King Chulalongkorn Memorial Hospital between January I and December 31, 2007. They filled it on a voluntary and anonymous basis. Each incident report was reviewed by three reviewers. Any disagreement was discussed to achieve a consensus. One hundred sixty three incident reports were filled reporting 191 incidents. There were fewer male (44%) than female (56%) patients and they had an ASA physical status classification 1 (41%), 2 (43%), 3 (10%), 4 (4%) and 5 (2%). Surgical specialties that posed high risk of incidents were general, orthopedic, gynecological, otorhino-laryngological and urological surgery. Locations of incident were operating room (85%), ward (8%) and recovery room (2%). The common adverse incidents were oxygen desaturation (23%), arrhythmia needing treatment (14%), equipment malfunction (13%), drug error (9%), difficult intubation (6%), esophageal intubation (5%), cardiac arrest (5%), reintubation (4%), and endobronchial intubation (4%). Adverse events were detected by monitoring only (27%), by monitoring before clinical diagnosis (26%), by clinical diagnosis before monitoring (21%), and by clinical diagnosis only (26%). Incidents were considered to be from anesthesia related factor (73%), system factor (16%) and preventable (47%). Common factors related to incident were inexperience, lack of vigilance, haste, inappropriate decision, not comply with guidelines, and lack of equipment maintenance. Suggested corrective strategies were quality assurance activity, additional

  9. Anthropogenic sulphur dioxide load over China as observed from different satellite sensors

    NASA Astrophysics Data System (ADS)

    Koukouli, M. E.; Balis, D. S.; van der A, Ronald Johannes; Theys, N.; Hedelt, P.; Richter, A.; Krotkov, N.; Li, C.; Taylor, M.

    2016-11-01

    China, with its rapid economic growth and immense exporting power, has been the focus of many studies during this previous decade quantifying its increasing emissions contribution to the Earth's atmosphere. With a population slowly shifting towards enlarged power and purchasing needs, the ceaseless inauguration of new power plants, smelters, refineries and industrial parks leads infallibly to increases in sulphur dioxide, SO2, emissions. The recent capability of next generation algorithms as well as new space-borne instruments to detect anthropogenic SO2 loads has enabled a fast advancement in this field. In the following work, algorithms providing total SO2 columns over China based on SCIAMACHY/Envisat, OMI/Aura and GOME2/MetopA observations are presented. The need for post-processing and gridding of the SO2 fields is further revealed in this work, following the path of previous publications. Further, it is demonstrated that the usage of appropriate statistical tools permits studying parts of the datasets typically excluded, such as the winter months loads. Focusing on actual point sources, such as megacities and known power plant locations, instead of entire provinces, monthly mean time series have been examined in detail. The sharp decline in SO2 emissions in more than 90%-95% of the locations studied confirms the recent implementation of government desulphurisation legislation; however, locations with increases, even for the previous five years, are also identified. These belong to provinces with emerging economies which are in haste to install power plants and are possibly viewed leniently by the authorities, in favour of growth. The SO2 load seasonality has also been examined in detail with a novel mathematical tool, with 70% of the point sources having a statistically significant annual cycle with highs in winter and lows in summer, following the heating requirements of the Chinese population.

  10. Enhanced configurational sampling with hybrid non-equilibrium molecular dynamics-Monte Carlo propagator

    NASA Astrophysics Data System (ADS)

    Suh, Donghyuk; Radak, Brian K.; Chipot, Christophe; Roux, Benoît

    2018-01-01

    Molecular dynamics (MD) trajectories based on classical equations of motion can be used to sample the configurational space of complex molecular systems. However, brute-force MD often converges slowly due to the ruggedness of the underlying potential energy surface. Several schemes have been proposed to address this problem by effectively smoothing the potential energy surface. However, in order to recover the proper Boltzmann equilibrium probability distribution, these approaches must then rely on statistical reweighting techniques or generate the simulations within a Hamiltonian tempering replica-exchange scheme. The present work puts forth a novel hybrid sampling propagator combining Metropolis-Hastings Monte Carlo (MC) with proposed moves generated by non-equilibrium MD (neMD). This hybrid neMD-MC propagator comprises three elementary elements: (i) an atomic system is dynamically propagated for some period of time using standard equilibrium MD on the correct potential energy surface; (ii) the system is then propagated for a brief period of time during what is referred to as a "boosting phase," via a time-dependent Hamiltonian that is evolved toward the perturbed potential energy surface and then back to the correct potential energy surface; (iii) the resulting configuration at the end of the neMD trajectory is then accepted or rejected according to a Metropolis criterion before returning to step 1. A symmetric two-end momentum reversal prescription is used at the end of the neMD trajectories to guarantee that the hybrid neMD-MC sampling propagator obeys microscopic detailed balance and rigorously yields the equilibrium Boltzmann distribution. The hybrid neMD-MC sampling propagator is designed and implemented to enhance the sampling by relying on the accelerated MD and solute tempering schemes. It is also combined with the adaptive biased force sampling algorithm to examine. Illustrative tests with specific biomolecular systems indicate that the method can yield

  11. Enhanced configurational sampling with hybrid non-equilibrium molecular dynamics-Monte Carlo propagator.

    PubMed

    Suh, Donghyuk; Radak, Brian K; Chipot, Christophe; Roux, Benoît

    2018-01-07

    Molecular dynamics (MD) trajectories based on classical equations of motion can be used to sample the configurational space of complex molecular systems. However, brute-force MD often converges slowly due to the ruggedness of the underlying potential energy surface. Several schemes have been proposed to address this problem by effectively smoothing the potential energy surface. However, in order to recover the proper Boltzmann equilibrium probability distribution, these approaches must then rely on statistical reweighting techniques or generate the simulations within a Hamiltonian tempering replica-exchange scheme. The present work puts forth a novel hybrid sampling propagator combining Metropolis-Hastings Monte Carlo (MC) with proposed moves generated by non-equilibrium MD (neMD). This hybrid neMD-MC propagator comprises three elementary elements: (i) an atomic system is dynamically propagated for some period of time using standard equilibrium MD on the correct potential energy surface; (ii) the system is then propagated for a brief period of time during what is referred to as a "boosting phase," via a time-dependent Hamiltonian that is evolved toward the perturbed potential energy surface and then back to the correct potential energy surface; (iii) the resulting configuration at the end of the neMD trajectory is then accepted or rejected according to a Metropolis criterion before returning to step 1. A symmetric two-end momentum reversal prescription is used at the end of the neMD trajectories to guarantee that the hybrid neMD-MC sampling propagator obeys microscopic detailed balance and rigorously yields the equilibrium Boltzmann distribution. The hybrid neMD-MC sampling propagator is designed and implemented to enhance the sampling by relying on the accelerated MD and solute tempering schemes. It is also combined with the adaptive biased force sampling algorithm to examine. Illustrative tests with specific biomolecular systems indicate that the method can yield

  12. Comprehensive imaging of tumor recurrence in breast cancer patients using whole-body MRI at 1.5 and 3 T compared to FDG-PET-CT.

    PubMed

    Schmidt, Gerwin P; Baur-Melnyk, Andrea; Haug, Alexander; Heinemann, Volker; Bauerfeind, Ingo; Reiser, Maximilian F; Schoenberg, Stefan O

    2008-01-01

    To compare the diagnostic accuracy for the detection of tumor recurrence in breast cancer patients using whole-body-MRI (WB-MRI) at 1.5 or 3T compared to FDG-PET-CT. Thirty-three female patients with breast cancer and suspicion of recurrence underwent FDG-PET-CT and WB-MRI. Coronal T1w-TSE- and STIR-sequences, HASTE-imaging of the lungs, contrast-enhanced T1w- and T2w-TSE-sequences of the liver, brain and abdomen were performed, using a WB-MRI-scanner at 1.5 (n=23) or 3T (n=10). Presence of local recurrence, lymph node involvement and distant metastatic disease was assessed using clinical and radiological follow-up as a standard of reference. Tumor recurrence was found in 20 of 33 patients. Overall 186 malignant foci were detected with WB-MRI and PET-CT. Both modalities revealed two recurrent tumors of the breast. PET-CT detected more lymph node metastases (n=21) than WB-MRI (n=16). WB-MRI was more precise in the detection of distant metastases (n=154 versus n=147). Sensitivity was 93% (172/186) and 91% (170/186) for WB-MRI and PET-CT, specificity was 86% (66/77) and 90% (69/77), respectively. Examination times for WB-MRI at 1.5 and 3T were 51 and 43 min, respectively, examination time for PET-CT was 103 min. WB-MRI and PET-CT are useful for the detection of tumor recurrence in the follow-up of breast cancer. WB-MRI is highly sensitive to distant metastatic disease. PET-CT is more sensitive in detecting lymph node involvement. Tumor screening with WB-MRI is feasible at 1.5 and 3T, scan time is further reduced at 3T with identical resolution.

  13. The Disposable Author: How Pharmaceutical Marketing Is Embraced within Medicine's Scholarly Literature.

    PubMed

    Matheson, Alastair

    2016-07-01

    2016 The Hastings Center.

  14. Influence of median surgeon operative duration on adverse outcomes in bariatric surgery.

    PubMed

    Reames, Bradley N; Bacal, Daniel; Krell, Robert W; Birkmeyer, John D; Birkmeyer, Nancy J O; Finks, Jonathan F

    2015-01-01

    Evidence suggests that prolonged operative time adversely affects surgical outcomes. However, whether faster surgeons have better outcomes is unclear, as a surgeon׳s speed could reflect skill and efficiency, but may alternatively reflect haste. This study evaluates whether median surgeon operative time is associated with adverse surgical outcomes after laparoscopic Roux-en-Y gastric bypass. We performed a retrospective cohort study using statewide clinical registry data from the years 2006 to 2012. Surgeons were ranked by their median operative time and grouped into terciles. Multivariable logistic regression with robust standard errors was used to evaluate the influence of median surgeon operative time on 30-day surgical outcomes, adjusting for patient and surgeon characteristics, trainee involvement, concurrent procedures, and the complex interaction between these variables. A total of 16,344 patients underwent surgery during the study period. Compared to surgeons in the fastest tercile, slow surgeons required 53 additional minutes to complete a gastric bypass procedure (median [interquartile range] 139 [133-150] versus 86 [69-91], P<.001). After adjustment for patient characteristic only, slow surgeons had significantly higher adjusted rates of any complication, prolonged length of stay, emergency department visits or readmissions, and venous thromboembolism (VTE). After further adjustment for surgeon characteristics, resident involvement, and the interaction between these variables, slow surgeons had higher rates of any complication (10.5% versus 7.1%, P=.039), prolonged length of stay (14.0% versus 4.4%, P=.002), and VTE (0.39% versus .22%, P<.001). Median surgeon operative duration is independently associated with adjusted rates of certain adverse outcomes after laparoscopic Roux-en-Y gastric bypass. Improving surgeon efficiency while operating may reduce operative time and improve the safety of bariatric surgery. Copyright © 2015 American Society for

  15. CBA and Precaution: Policy-Making about Emerging Technologies.

    PubMed

    Kaebnick, Gregory E; Gusmano, Michael K

    2018-01-01

    In the technology assessment literature, the leading alternative to CBA-like methods is usually held to be precaution, which is understood in various ways but is always about making decisions under conditions of uncertainty. Under such conditions, proponents of precaution commonly hold, a straightforward tallying of potential outcomes does not seem possible. Since CBA aims to tally up outcomes to determine which outcome would produce the greatest public benefit, precaution begins to look like, not just an alternative to CBA, but an incompatible alternative. Nonetheless, some of the better-known formulations of a precautionary principle expressly call for combining precaution with assessment of costs and benefits. This essay examines the possible intersection of precaution and CBA. It argues that a moderate kind of CBA is a necessary part of a moderate kind of precaution. The existing proposals for integrating CBA and precaution start with an assumption that the integrative task consists in combining decision tools that generate (contrasting) substantive guidance. An alternative approach, explored here, starts with the idea that precaution is not a decision-generating tool. Rather, it is a way of organizing the thinking that leads eventually to substantive conclusions. The appropriate policy response is reached not by applying a principle but by studying the situation-the proposed action and the problem it is meant to address-and developing recommendations tailored to it. What makes the thinking precautionary is that it emphasizes certain questions-about risk, uncertainty, and values-that CBA tends to suppress. So understood, precaution may well slow the science but is not intrinsically opposed to science or innovation. It can be understood, in fact, as continuous with the science because the contextual understanding of the science and the problems it is meant to address would emerge-in part-from a close engagement with the science. © 2018 The Hastings Center.

  16. Why Bioethics Needs a Disability Moral Psychology.

    PubMed

    Stramondo, Joseph A

    2016-05-01

    The deeply entrenched, sometimes heated conflict between the disability movement and the profession of bioethics is well known and well documented. Critiques of prenatal diagnosis and selective abortion are probably the most salient and most sophisticated of disability studies scholars' engagements with bioethics, but there are many other topics over which disability activists and scholars have encountered the field of bioethics in an adversarial way, including health care rationing, growth-attenuation interventions, assisted reproduction technology, and physician-assisted suicide. The tension between the analyses of the disabilities studies scholars and mainstream bioethics is not merely a conflict between two insular political groups, however; it is, rather, also an encounter between those who have experienced disability and those who have not. This paper explores that idea. I maintain that it is a mistake to think of this conflict as arising just from a difference in ideology or political commitments because it represents a much deeper difference-one rooted in variations in how human beings perceive and reason about moral problems. These are what I will refer to as variations of moral psychology. The lived experiences of disability produce variations in moral psychology that are at the heart of the moral conflict between the disability movement and mainstream bioethics. I will illustrate this point by exploring how the disability movement and mainstream bioethics come into conflict when perceiving and analyzing the moral problem of physician-assisted suicide via the lens of the principle of respect for autonomy. To reconcile its contemporary and historical conflict with the disability movement, the field of bioethics must engage with and fully consider the two groups' differences in moral perception and reasoning, not just the explicit moral and political arguments of the disability movement. © 2016 The Hastings Center.

  17. Empirical research in bioethical journals. A quantitative analysis

    PubMed Central

    Borry, P; Schotsmans, P; Dierickx, K

    2006-01-01

    Objectives The objective of this research is to analyse the evolution and nature of published empirical research in the fields of medical ethics and bioethics. Design Retrospective quantitative study of nine peer reviewed journals in the field of bioethics and medical ethics (Bioethics, Cambridge Quarterly of Healthcare Ethics, Hastings Center Report, Journal of Clinical Ethics, Journal of Medical Ethics, Kennedy Institute of Ethics Journal, Nursing Ethics, Christian Bioethics, andTheoretical Medicine and Bioethics). Results In total, 4029 articles published between 1990 and 2003 were retrieved from the journals studied. Over this period, 435 (10.8%) studies used an empirical design. The highest percentage of empirical research articles appeared in Nursing Ethics (n = 145, 39.5%), followed by the Journal of Medical Ethics (n = 128, 16.8%) and the Journal of Clinical Ethics (n = 93, 15.4%). These three journals account for 84.1% of all empirical research in bioethics published in this period. The results of the χ2 test for two independent samples for the entire dataset indicate that the period 1997–2003 presented a higher number of empirical studies (n = 309) than did the period 1990–1996 (n = 126). This increase is statistically significant (χ2 = 49.0264, p<.0001). Most empirical studies employed a quantitative paradigm (64.6%, n = 281). The main topic of research was prolongation of life and euthanasia (n = 68). Conclusions We conclude that the proportion of empirical research in the nine journals increased steadily from 5.4% in 1990 to 15.4% in 2003. It is likely that the importance of empirical methods in medical ethics and bioethics will continue to increase. PMID:16574880

  18. Quantum dot transport in soil, plants, and insects.

    PubMed

    Al-Salim, Najeh; Barraclough, Emma; Burgess, Elisabeth; Clothier, Brent; Deurer, Markus; Green, Steve; Malone, Louise; Weir, Graham

    2011-08-01

    Environmental risk assessment of nanomaterials requires information not only on their toxicity to non-target organisms, but also on their potential exposure pathways. Here we report on the transport and fate of quantum dots (QDs) in the total environment: from soils, through their uptake into plants, to their passage through insects following ingestion. Our QDs are nanoparticles with an average particle size of 6.5 nm. Breakthrough curves obtained with CdTe/mercaptopropionic acid QDs applied to columns of top soil from a New Zealand organic apple orchard, a Hastings silt loam, showed there to be preferential flow through the soil's macropores. Yet the effluent recovery of QDs was just 60%, even after several pore volumes, indicating that about 40% of the influent QDs were filtered and retained by the soil column via some unknown exchange/adsorption/sequestration mechanism. Glycine-, mercaptosuccinic acid-, cysteine-, and amine-conjugated CdSe/ZnS QDs were visibly transported to a limited extent in the vasculature of ryegrass (Lolium perenne), onion (Allium cepa) and chrysanthemum (Chrysanthemum sp.) plants when cut stems were placed in aqueous QD solutions. However, they were not seen to be taken up at all by rooted whole plants of ryegrass, onion, or Arabidopsis thaliana placed in these solutions. Leafroller (Lepidoptera: Tortricidae) larvae fed with these QDs for two or four days, showed fluorescence along the entire gut, in their frass (larval feces), and, at a lower intensity, in their haemolymph. Fluorescent QDs were also observed and elevated cadmium levels detected inside the bodies of adult moths that had been fed QDs as larvae. These results suggest that exposure scenarios for QDs in the total environment could be quite complex and variable in each environmental domain. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Firefighter safety: rampant unsafe practices as documented in mainstream media.

    PubMed

    Kahn, Steven A; Woods, Jason; Sipes, Jan C; Toscano, Nicole; Bell, Derek E

    2014-01-01

    More than 30,000 firefighters are injured on the fireground each year. Literature suggests that injury often occurs when protective gear is not used properly. According to firefighters, failure to correctly wear protective equipment occurs for several reasons: (1) gear not used because of haste, (2) cumbersome gear can sometimes interfere with performance, and (3) cultural factors. The purpose of this study is to quantify improper gear and tactic use in a publicly available, online video repository in order to better understand unsafe firefighting. This was an Institutional Review Board-exempt study of public video records. A search for "fire fighting videos" was conducted at YouTube (www.youtube.com). The first 50 videos that contained volunteer or career firefighters at work fighting fires were selected evaluated for appropriate use of personal protective equipment and for safe behavior. The videos were evaluated by two highly experienced professional firefighters. Of the 50 videos reviewed, 25 (50%) demonstrated violations of firefighting safety principles. Of the unsafe videos, 21 (42%) displayed firefighters improperly using gear, while the other 4 (8%) were related to unsound tactics. The most common problem was failure to wear or properly secure a self-contained breathing apparatus when appropriate (14 videos or 28%). The second most common failure was lack of helmet, hood, or approved gloves (11 videos or 22%). In conclusion, firefighting as documented on YouTube is often unsafe because of failure to properly use personal protective equipment. Half of the videos reviewed contained unsafe practices. With such a shockingly high rate of unsafe firefighting, the profession is in need of additional education and reform. In response to this epidemic, a multidisciplinary educational program has been developed to improve firefighter awareness of gear limitations and burn injury risk. Effectiveness of educational programs should be documented in additional

  20. An implementation of differential evolution algorithm for inversion of geoelectrical data

    NASA Astrophysics Data System (ADS)

    Balkaya, Çağlayan

    2013-11-01

    Differential evolution (DE), a population-based evolutionary algorithm (EA) has been implemented to invert self-potential (SP) and vertical electrical sounding (VES) data sets. The algorithm uses three operators including mutation, crossover and selection similar to genetic algorithm (GA). Mutation is the most important operator for the success of DE. Three commonly used mutation strategies including DE/best/1 (strategy 1), DE/rand/1 (strategy 2) and DE/rand-to-best/1 (strategy 3) were applied together with a binomial type crossover. Evolution cycle of DE was realized without boundary constraints. For the test studies performed with SP data, in addition to both noise-free and noisy synthetic data sets two field data sets observed over the sulfide ore body in the Malachite mine (Colorado) and over the ore bodies in the Neem-Ka Thana cooper belt (India) were considered. VES test studies were carried out using synthetically produced resistivity data representing a three-layered earth model and a field data set example from Gökçeada (Turkey), which displays a seawater infiltration problem. Mutation strategies mentioned above were also extensively tested on both synthetic and field data sets in consideration. Of these, strategy 1 was found to be the most effective strategy for the parameter estimation by providing less computational cost together with a good accuracy. The solutions obtained by DE for the synthetic cases of SP were quite consistent with particle swarm optimization (PSO) which is a more widely used population-based optimization algorithm than DE in geophysics. Estimated parameters of SP and VES data were also compared with those obtained from Metropolis-Hastings (M-H) sampling algorithm based on simulated annealing (SA) without cooling to clarify uncertainties in the solutions. Comparison to the M-H algorithm shows that DE performs a fast approximate posterior sampling for the case of low-dimensional inverse geophysical problems.

  1. Intra-thoracic fat volume is associated with myocardial infarction in patients with metabolic syndrome.

    PubMed

    Jolly, Umjeet S; Soliman, Abraam; McKenzie, Charles; Peters, Terry; Stirrat, John; Nevis, Immaculate; Brymer, Matthew; Joy, Tisha; Drangova, Maria; White, James A

    2013-09-10

    Visceral adiposity is increased in those with Metabolic Syndrome (MetS) and atherosclerotic disease burden. In this study we evaluate for associations between intra-thoracic fat volume (ITFV) and myocardial infarction (MI) in patients with MetS. Ninety-four patients with MetS, MI or both were identified from a cardiovascular CMR clinical registry. MetS was defined in accordance to published guidelines; where-as MI was defined as the presence of subendocardial-based injury on late gadolinium enhancement imaging in a coronary vascular distribution. A healthy control group was also obtained from the same registry. Patients were selected into the following groups: MetS+/MI- (N = 32), MetS-/MI + (N = 30), MetS+/MI + (N = 32), MetS-/MI- (N = 16). ITFV quantification was performed using signal threshold analysis of sequential sagittal CMR datasets (HASTE) and indexed to body mass index. The mean age of the population was 59.8 ± 12.5 years. MetS+ patients (N=64) demonstrated a significantly higher indexed ITFV compared to MetS- patients (p = 0.05). Patients in respective MetS-/MI-, MetS+/MI-, MetS-/MI+, and MetS+/MI + study groups demonstrated a progressive elevation in the indexed ITFV (22.3 ± 10.6, 28.6 ± 12.6, 30.6 ± 12.3, and 35.2 ± 1.4 ml/kg/m(2), (p = 0.002)). Among MetS+ patients those with MI showed a significantly higher indexed ITFV compared to those without MI (p = 0.02). ITFV is elevated in patients with MetS and incrementally elevated among those with evidence of prior ischemic myocardial injury. Accordingly, the quantification of ITFV may be a valuable marker of myocardial infarction risk among patients with MetS and warrants further investigation.

  2. Planning and implementing an honors degree in environmental science curricula: a case study from the University of Delaware, USA

    NASA Astrophysics Data System (ADS)

    Levia, Delphis

    2015-04-01

    advisory Environmental Council include Drs. Delphis Levia (Program Director & Chair), Nancy Targett (Dean), Frank Newton, Tracy Deliberty, Steve Hastings, John Madsen, Paul Imhoff, Jan Johnson, Jerry Kauffman, Murray Johnston.

  3. Does speed matter? The impact of operative time on outcome in laparoscopic surgery.

    PubMed

    Jackson, Timothy D; Wannares, Jeffrey J; Lancaster, R Todd; Rattner, David W; Hutter, Matthew M

    2011-07-01

    Controversy exists concerning the importance of operative time on patient outcomes. It is unclear whether faster is better or haste makes waste or similarly whether slower procedures represent a safe, meticulous approach or inexperienced dawdling. The objective of the present study was to determine the effect of operative time on 30-day outcomes in laparoscopic surgery. Patients who underwent laparoscopic general surgery procedures (colectomy, cholecystectomy, Nissen fundoplication, inguinal hernia, and gastric bypass) from the ACS-NSQIP 2005-2008 participant use file were identified. Exclusion criteria were defined a priori to identify same-day admission, elective procedures. Operative time was divided into deciles and summary statistics were analyzed. Univariate analyses using a Cochran-Armitage test for trend were completed. The effect of operative time on 30-day morbidity was further analyzed for each procedure type using multivariate regression controlling for case complexity and additional patient factors. Patients within the highest deciles were excluded to reduce outlier effect. A total of 76,748 elective general surgical patients who underwent laparoscopic procedures were analyzed. Univariate analyses of deciles of operative time demonstrated a statistically significant trend (p<0.0001) toward increasing odds of complications with increasing operative time for laparoscopic colectomy (n=10,135), cholecystectomy (n=37,407), Nissen fundoplication (n=4,934), and gastric bypass (n=17,842). The trend was not found to be significant for laparoscopic inguinal hernia repair (n=6,430; p=0.14). Multivariate modeling revealed the effect of operative time to remain significant after controlling for additional patient factors. Increasing operative time was associated with increased odds of complications and, therefore, it appears that speed may matter in laparoscopic surgery. These analyses are limited in their inability to adjust for all patient factors, potential

  4. Changes in the social context and conduct of eating in four Nordic countries between 1997 and 2012.

    PubMed

    Holm, Lotte; Lauridsen, Drude; Lund, Thomas Bøker; Gronow, Jukka; Niva, Mari; Mäkelä, Johanna

    2016-08-01

    How have eating patterns changed in modern life? In public and academic debate concern has been expressed that the social function of eating may be challenged by de-structuration and the dissolution of traditions. We analyzed changes in the social context and conduct of eating in four Nordic countries over the period 1997-2012. We focused on three interlinked processes often claimed to be distinctive of modern eating: delocalization of eating from private households to commercial settings, individualization in the form of more eating alone, and informalization, implying more casual codes of conduct. We based the analysis on data from two surveys conducted in Denmark, Finland, Norway and Sweden in 1997 and 2012. The surveys reported in detail one day of eating in representative samples of adult populations in the four countries (N = 4823 and N = 8242). We compared data regarding where, with whom, and for how long people ate, and whether parallel activities took place while eating. While Nordic people's primary location for eating remained the home and the workplace, the practices of eating in haste, and while watching television increased and using tablets, computers and smartphones while eating was frequent in 2012. Propensity to eat alone increased slightly in Denmark and Norway, and decreased slightly in Sweden. While such practices vary with socio-economic background, regression analysis showed several changes were common across the Nordic populations. However, the new practice of using tablets, computers, and smartphones while eating was strongly associated with young age. Further, each of the practices appeared to be related to different types of meal. We conclude that while the changes in the social organization of eating were not dramatic, signs of individualization and informalization could be detected. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Positive deviance as a strategy to prevent and control bloodstream infections in intensive care.

    PubMed

    Oliveira, Francimar Tinoco de; Ferreira, Maria Manuela Frederico; Araújo, Silvia Teresa Carvalho de; Bessa, Amanda Trindade Teixeira de; Moraes, Advi Catarina Barbachan; Stipp, Marluci Andrade Conceição

    2017-04-03

    To describe the application of positive deviance as a strategy to prevent and control bloodstream infections. An intervention study with nursing and medical team members working in an intensive care unit in a university hospital, between June and December 2014. The four steps of the positive defiance methodology were applied: to define, to determine, to discover and to design. In 90 days, 188 actions were observed, of these, 36.70% (n=69) were related to catheter dressing. In 81.15% (n=56) of these dressings, the professionals most adhered to the use of flexible sterile cotton-tipped swabs to perform antisepsis at catheter entry sites and fixation dressing. Positive deviance contributed to the implementation of proposals to improve work processes and team development related to problems identified in central venous catheter care. Descrever a aplicação do Positive Deviance como estratégia na prevenção e no controle da infecção de corrente sanguínea. Estudo de intervenção realizado na Unidade de Terapia Intensiva de um hospital universitário, com os membros das equipes de enfermagem e médica, de junho a dezembro de 2014. Foram aplicados os quatro passos da metodologia Positive Deviance: Definir, Determinar, Descobrir e Desenhar. Em 90 dias 188 ações foram observadas, destas, 36,70% (n=69) estavam relacionadas aos curativos dos cateteres. Em 81,15% (n=56) desses curativos, o uso da haste flexível estéril para realização da antissepsia do local de inserção do cateter e de sua placa de fixação foi a ação de maior adesão. O Positive Deviance auxiliou na implementação de propostas de melhorias de processo de trabalho e no desenvolvimento da equipe para os problemas identificados no cuidado com o cateter venoso central.

  6. Integration of climate change in flood prediction: application to the Somme river (France)

    NASA Astrophysics Data System (ADS)

    Pinault, J.-L.; Amraoui, N.; Noyer, M.-L.

    2003-04-01

    Exceptional floods that have occurred for the last two years in western and central Europe were very unlikely. The concomitance of such rare events shows that they might be imputable to climate change. The statistical analysis of long rainfall series confirms that both the cumulated annual height and the temporal variability have increased for the last decade. This paper is devoted to the analysis of climate change impact on flood prediction applied to the Somme river. The exceptional pluviometry that occurred from October 2000 to April 2001, about the double of the mean value, entailed catastrophic flood between the high Somme and Abbeville. The flow reached a peak at the beginning of May 2001, involving damages in numerous habitations and communication routes, and economical activity of the region had been flood-bound for more than 2 months. The flood caught unaware the population and caused deep traumas in France since it was the first time such a sudden event was recognized as resulting from groundwater discharge. Mechanisms of flood generation were studied tightly in order to predict the behavior of the Somme catchment and other urbanized basins when the pluviometry is exceptional in winter or in spring, which occurs more and more frequently in the northern part of Europe. The contribution of groundwater in surface water flow was calculated by inverse modeling from piezometers that are representative of aquifers in valleys. They were found on the slopes and near the edge of plateaus in order to characterize the drainage processes of the watertable to the surface water network. For flood prediction, a stochastic process is used, consisting in the generation of both rainfall and PET time series. The precipitation generator uses Markov chain Monte Carlo and simulated annealing from the Hastings -- Metropolis algorithm. Coupling of rainfall and PET generators with transfer enables a new evaluation of the probability of occurrence of floods, taking into account

  7. A simple approach to CO cooling in molecular clouds

    NASA Astrophysics Data System (ADS)

    Whitworth, A. P.; Jaffa, S. E.

    2018-03-01

    Carbon monoxide plays an important role in interstellar molecular clouds, both as a coolant, and as a diagnostic molecule. However, a proper evaluation of the cooling rate due to CO requires a determination of the populations of many levels, the spontaneous and stimulated radiative de-excitation rates between these levels, and the transfer of the emitted multi-line radiation; additionally, this must be done for three isotopologues. It would be useful to have a simple analytic formulation that avoided these complications and the associated computational overhead; this could then be used in situations where CO plays an important role as a coolant, but the details of this role are not the main concern. We derive such a formulation here, by first considering the two asymptotic forms that obtain in the limits of (a) low volume-density and optical depth, and (b) high volume-density and optical depth. These forms are then combined in such a way as to fit the detailed numerical results from Goldsmith & Langer (1978, ApJ, 222, 881; hereafter GL78). The GL78 results cover low temperatures, and a range of physical conditions where the interplay of thermal and sub-thermal excitation, optical-depth effects, and the contributions from rare isotopologues, are all important. The fit is obtained using the Metropolis-Hastings method, and reproduces the results of GL78 well. It is a purely local and analytic function of state — specifically a function of the density, ρ, isothermal sound speed, a, CO abundance, XCO, and velocity divergence, ∇ṡυ. As an illustration of its use, we consider the cooling layer following a slow steady non-magnetic planar J-shock. We show that, in this idealised configuration, if the post-shock cooling is dominated by CO and its isotopologues, the thickness of the post-shock cooling layer is very small and approximately independent of the pre-shock velocity, υo, or pre-shock isothermal sound speed, ao.

  8. Comparison of model microbial allocation parameters in soils of varying texture

    NASA Astrophysics Data System (ADS)

    Hagerty, S. B.; Slessarev, E.; Schimel, J.

    2017-12-01

    The soil microbial community decomposes the majority of carbon (C) inputs to the soil. However, not all of this C is respired—rather, a substantial portion of the carbon processed by microbes may remain stored in the soil. The balance between C storage and respiration is controlled by microbial turnover rates and C allocation strategies. These microbial community properties may depend on soil texture, which has the potential to influence both the nature and the fate of microbial necromass and extracellular products. To evaluate the role of texture on microbial turnover and C allocation, we sampled four soils from the University of California's Hastings Reserve that varied in texture (one silt loam, two sandy loam, and on clay soil), but support similar grassland plant communities. We added 14C- glucose to the soil and measured the concentration of the label in the carbon dioxide (CO2), microbial biomass, and extractable C pools over 7 weeks. The labeled biomass turned over the slowest in the clay soil; the concentration of labeled biomass was more than 1.5 times the concentration of the other soils after 8 weeks. The clay soil also had the lowest mineralization rate of the label, and mineralization slowed after two weeks. In contrast, in the sandier soils mineralization rates were higher and did not plateau until 5 weeks into the incubation period. We fit the 14C data to a microbial allocation model and estimated microbial parameters; assimilation efficiency, exudation, and biomass specific respiration and turnover for each soil. We compare these parameters across the soil texture gradient to assess the extent to which models may need to account for variability in microbial C allocation across soils of different texture. Our results suggest that microbial C turns over more slowly in high-clay soils than in sandy soils, and that C lost from microbial biomass is retained at higher rates in high-clay soils. Accounting for these differences in microbial allocation

  9. On the Tracy-Widomβ Distribution for β=6

    NASA Astrophysics Data System (ADS)

    Grava, Tamara; Its, Alexander; Kapaev, Andrei; Mezzadri, Francesco

    2016-11-01

    We study the Tracy-Widom distribution function for Dyson's β-ensemble with β = 6. The starting point of our analysis is the recent work of I. Rumanov where he produces a Lax-pair representation for the Bloemendal-Virág equation. The latter is a linear PDE which describes the Tracy-Widom functions corresponding to general values of β. Using his Lax pair, Rumanov derives an explicit formula for the Tracy-Widom β=6 function in terms of the second Painlevé transcendent and the solution of an auxiliary ODE. Rumanov also shows that this formula allows him to derive formally the asymptotic expansion of the Tracy-Widom function. Our goal is to make Rumanov's approach and hence the asymptotic analysis it provides rigorous. In this paper, the first one in a sequel, we show that Rumanov's Lax-pair can be interpreted as a certain gauge transformation of the standard Lax pair for the second Painlevé equation. This gauge transformation though contains functional parameters which are defined via some auxiliary nonlinear ODE which is equivalent to the auxiliary ODE of Rumanov's formula. The gauge-interpretation of Rumanov's Lax-pair allows us to highlight the steps of the original Rumanov's method which needs rigorous justifications in order to make the method complete. We provide a rigorous justification of one of these steps. Namely, we prove that the Painlevé function involved in Rumanov's formula is indeed, as it has been suggested by Rumanov, the Hastings-McLeod solution of the second Painlevé equation. The key issue which we also discuss and which is still open is the question of integrability of the auxiliary ODE in Rumanov's formula. We note that this question is crucial for the rigorous asymptotic analysis of the Tracy-Widom function. We also notice that our work is a partial answer to one of the problems related to the β-ensembles formulated by Percy Deift during the June 2015 Montreal Conference on integrable systems.

  10. GBIS (Geodetic Bayesian Inversion Software): Rapid Inversion of InSAR and GNSS Data to Estimate Surface Deformation Source Parameters and Uncertainties

    NASA Astrophysics Data System (ADS)

    Bagnardi, M.; Hooper, A. J.

    2017-12-01

    Inversions of geodetic observational data, such as Interferometric Synthetic Aperture Radar (InSAR) and Global Navigation Satellite System (GNSS) measurements, are often performed to obtain information about the source of surface displacements. Inverse problem theory has been applied to study magmatic processes, the earthquake cycle, and other phenomena that cause deformation of the Earth's interior and of its surface. Together with increasing improvements in data resolution, both spatial and temporal, new satellite missions (e.g., European Commission's Sentinel-1 satellites) are providing the unprecedented opportunity to access space-geodetic data within hours from their acquisition. To truly take advantage of these opportunities we must become able to interpret geodetic data in a rapid and robust manner. Here we present the open-source Geodetic Bayesian Inversion Software (GBIS; available for download at http://comet.nerc.ac.uk/gbis). GBIS is written in Matlab and offers a series of user-friendly and interactive pre- and post-processing tools. For example, an interactive function has been developed to estimate the characteristics of noise in InSAR data by calculating the experimental semi-variogram. The inversion software uses a Markov-chain Monte Carlo algorithm, incorporating the Metropolis-Hastings algorithm with adaptive step size, to efficiently sample the posterior probability distribution of the different source parameters. The probabilistic Bayesian approach allows the user to retrieve estimates of the optimal (best-fitting) deformation source parameters together with the associated uncertainties produced by errors in the data (and by scaling, errors in the model). The current version of GBIS (V1.0) includes fast analytical forward models for magmatic sources of different geometry (e.g., point source, finite spherical source, prolate spheroid source, penny-shaped sill-like source, and dipping-dike with uniform opening) and for dipping faults with uniform

  11. Extracting and Applying SV-SV Shear Modes from Vertical Vibrator Data Across Geothermal Prospects Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hardage, Bob

    2013-07-01

    This 3-year project was terminated at the end of Year 1 because the DOE Geothermal project-evaluation committee decided one Milestone was not met and also concluded that our technology would not be successful. The Review Panel recommended a ?no-go? decision be implemented by DOE. The Principal Investigator and his research team disagreed with the conclusions reached by the DOE evaluation committee and wrote a scientifically based rebuttal to the erroneous claims made by the evaluators. We were not told if our arguments were presented to the people who evaluated our work and made the ?no-go? decision. Whatever the case regardingmore » the information we supplied in rebuttal, we received an official letter from Laura Merrick, Contracting Officer at the Golden Field Office, dated June 11, 2013 in which we were informed that project funding would cease and instructed us to prepare a final report before September 5, 2013. In spite of the rebuttal arguments we presented to DOE, this official letter repeated the conclusions of the Review Panel that we had already proven to be incorrect. This is the final report that we are expected to deliver. The theme of this report will be another rebuttal of the technical deficiencies claimed by the DOE Geothermal Review Panel about the value and accomplishments of the work we did in Phase 1 of the project. The material in this report will present images made from direct-S modes produced by vertical-force sources using the software and research findings we developed in Phase 1 that the DOE Review Panel said would not be successful. We made these images in great haste when we were informed that DOE Geothermal rejected our rebuttal arguments and still regarded our technical work to be substandard. We thought it was more important to respond quickly rather than to take additional time to create better quality images than what we present in this Final Report.« less

  12. A history of psychiatric ethics.

    PubMed

    Bloch, Sidney; Pargiter, Russell

    2002-09-01

    In the not-far-distant past, ethics for all doctors was, at best, an ill-attended lecture or two on how to keep out of trouble; it was assumed the rest was absorbed by a form of social and professional osmosis. Although ethics has entered the undergraduate curriculum, continuing medical education programs, journals, and books, it still is in a state of flux. Although immense progress has been made in the last 30 to 40 years, much remains to be done. Trainees are often naïve, and the older generation is on a steep learning curve. An encouraging feature is the current lively debate on matters ethical and how they can best be incorporated into everyday clinical practice. The long-held notion of ethics resting complacently in the paternal arms of Hippocrates has, with almost brutal haste, been projected into a rapidly evolving modern world of technologic, moral, and societal change. Yet, at its core, ethics has to retain its humanism and guard against influences from every quarter that tries to make it a set of rules, thereby negating the diversity and uniqueness of our patients. Even as you read, there will be new influences and pressures on clinical practice that have an ethical dimension. For instance, we are adjusting to new privacy laws in Australia that allow patients, whether public or private, access to their psychiatric records. Globalization is not restricted to world trade; it also operates in the framework of societal change and the wider dissemination and implementation of libertarian views. If such "freedoms" are not currently available to patients, they soon will be. This brief historical foray in identifying some of these forces can assist in their early recognition so that as a profession, we are forewarned and forearmed and, in that respect, be ahead of both Henry Ford ("History is more or less bunk...") [42] and the Bourbons ("They learn nothing and they forget nothing") [43].

  13. Model-independent limits and constraints on extended theories of gravity from cosmic reconstruction techniques

    NASA Astrophysics Data System (ADS)

    de la Cruz-Dombriz, Álvaro; Dunsby, Peter K. S.; Luongo, Orlando; Reverberi, Lorenzo

    2016-12-01

    The onset of dark energy domination depends on the particular gravitational theory driving the cosmic evolution. Model independent techniques are crucial to test the both the present ΛCDM cosmological paradigm and alternative theories, making the least possible number of assumptions about the Universe. In this paper we investigate whether cosmography is able to distinguish between different gravitational theories, by determining bounds on model parameters for three different extensions of General Relativity, namely quintessence, F(𝒯) and f(R) gravitational theories. We expand each class of theories in powers of redshift z around the present time, making no additional assumptions. This procedure is an extension of previous work and can be seen as the most general approach for testing extended theories of gravity through the use of cosmography. In the case of F(𝒯) and f(R) theories, we show that some assumptions on model parameters often made in previous works are superfluous or even unjustified. We use data from the Union 2.1 supernovae catalogue, baryonic acoustic oscillation data and H(z) differential age compilations, which probe cosmology on different scales of the cosmological evolution. We perform a Monte Carlo analysis using a Metropolis-Hastings algorithm with a Gelman-Rubin convergence criterion, reporting 1-σ and 2-σ confidence levels. To do so, we perform two distinct fits, assuming only data within z < 1 first and then without limitations in redshift. We obtain the corresponding numerical intervals in which coefficients span, and find that the data is compatible the ΛCDM limit of all three theories at the 1-σ level, while still compatible with quite a large portion of parameter space. We compare our results to the truncated ΛCDM paradigm, demonstrating that our bounds divert from the expectations of previous works, showing that the permitted regions of coefficients are significantly modified and in general widened with respect to

  14. Fit for high altitude: are hypoxic challenge tests useful?

    PubMed

    Matthys, Heinrich

    2011-02-28

    Altitude travel results in acute variations of barometric pressure, which induce different degrees of hypoxia, changing the gas contents in body tissues and cavities. Non ventilated air containing cavities may induce barotraumas of the lung (pneumothorax), sinuses and middle ear, with pain, vertigo and hearing loss. Commercial air planes keep their cabin pressure at an equivalent altitude of about 2,500 m. This leads to an increased respiratory drive which may also result in symptoms of emotional hyperventilation. In patients with preexisting respiratory pathology due to lung, cardiovascular, pleural, thoracic neuromuscular or obesity-related diseases (i.e. obstructive sleep apnea) an additional hypoxic stress may induce respiratory pump and/or heart failure. Clinical pre-altitude assessment must be disease-specific and it includes spirometry, pulsoximetry, ECG, pulmonary and systemic hypertension assessment. In patients with abnormal values we need, in addition, measurements of hemoglobin, pH, base excess, PaO2, and PaCO2 to evaluate whether O2- and CO2-transport is sufficient.Instead of the hypoxia altitude simulation test (HAST), which is not without danger for patients with respiratory insufficiency, we prefer primarily a hyperoxic challenge. The supplementation of normobaric O2 gives us information on the acute reversibility of the arterial hypoxemia and the reduction of ventilation and pulmonary hypertension, as well as about the efficiency of the additional O2-flow needed during altitude exposure. For difficult judgements the performance of the test in a hypobaric chamber with and without supplemental O2-breathing remains the gold standard. The increasing numbers of drugs to treat acute pulmonary hypertension due to altitude exposure (acetazolamide, dexamethasone, nifedipine, sildenafil) or to other etiologies (anticoagulants, prostanoids, phosphodiesterase-5-inhibitors, endothelin receptor antagonists) including mechanical aids to reduce periodical or

  15. Final Work Plan: Phase I Investigation at Bladen, Nebraska

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaFreniere, Lorraine M.; Yan, Eugene

    The village of Bladen is a town of population approximately 237 in the northwest part of Webster County, Nebraska, 30 mi southwest of Hastings and 140 mi southwest of Lincoln, Nebraska. In 2000, the fumigant-related compound carbon tetrachloride was detected in public water supply well PWS 68-1, at a trace level. Low-level contamination, below the maximum contamination level (MCL) of 5.0 μg/L, has been detected intermittently in well PWS 68-1 since 2000, including in the last sample taken in July 2013. In 2006, the village installed a new well, PWS 2006-1, that remains free of contamination. Because the carbon tetrachloridemore » found in well PWS 68-1 might be linked to historical use of fumigants containing carbon tetrachloride at grain storage facilities, including its former facility in Bladen, the CCC/USDA is proposing an investigation to (1) delineate the source and extent of the carbon tetrachloride contamination potentially associated with its former facility, (2) characterize pathways and controlling factors for contaminant migration in the subsurface, and (3) establish a basis for estimating potential health and environmental risks. The work will be performed in accordance with the Intergovernmental Agreement established between the NDEQ and the Farm Service Agency of the USDA. The site investigation at Bladen will be implemented in phases, so that data collected and interpretations developed during each phase can be evaluated to determine if a subsequent phase of investigation is warranted and, if warranted, to provide effective guidance for the subsequent investigation activities. This Work Plan identifies the specific technical objectives and defines the scope of work proposed for the Phase I investigation by compiling and evaluating historical data. The proposed investigation activities will be performed on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research

  16. Patients as Rights Holders.

    PubMed

    Brännmark, Johan

    2017-07-01

    Autonomy and consent have been central values in Western moral and political thought for centuries. One way of understanding the bioethical models that started to develop, especially in the 1970s, is that they were about the fusion of a long-standing professional ethics with the core values underpinning modern political institutions. That there was a need for this kind of fusion is difficult to dispute, especially since the provision of health care has in most developed countries become an ever more important concern of our political institutions, with governments playing a significant role in regulating and facilitating the provision of health care and in many countries even largely organizing it. There is, nevertheless, still room for dispute about how best to achieve this fusion and how to best think about autonomy and consent in a biomedical context. The simplest model we can have is probably about how being a person is largely about having the capacity of autonomous choice and that the main mode through which we exercise autonomy is by providing informed consent. Yet, liberal democracy's core idea that human beings have a high and equal value is also found in other accounts of the person. The human-rights framework provides an alternative model for thinking about personhood and about patient care. The human-rights approach is grounded, not in an account of autonomy (although it has something to say about autonomy), but in an account of the moral and political personhood that people possess merely by being human beings. In this approach, values like dignity and integrity, both highly relevant in a bioethical context, are identified as distinct values rather than being derived from and therefore reduced to respect for autonomous choice. The human-rights approach can supplement the problematic notion of autonomy that has been central to bioethics by placing this notion in a broader, strongly pluralistic framework. © 2017 The Hastings Center.

  17. Reconciling conceptualizations of relationships and person-centred care for older people with cognitive impairment in acute care settings.

    PubMed

    Rushton, Carole; Edvardsson, David

    2018-04-01

    Relationships are central to enacting person-centred care of the older person with cognitive impairment. A fuller understanding of relationships and the role they play facilitating wellness and preserving personhood is critical if we are to unleash the productive potential of nursing research and person-centred care. In this article, we target the acute care setting because much of the work about relationships and older people with cognitive impairment has tended to focus on relationships in long-term care. The acute care setting is characterized by archetypal constraints which differentiate it from long-term care, in terms of acuity and haste, task-orientated work patterns and influence from "the rule of medicine," all of which can privilege particular types of relating. In this article, we drew on existing conceptualizations of relationships from theory and practice by tapping in to the intellectual resources provided by nurse researchers, the philosophy of Martin Buber and ANT scholars. This involved recounting two examples of dyadic and networked relationships which were re-interpreted using two complementary theoretical approaches to provide deeper and more comprehensive conceptualizations of these relationships. By re-presenting key tenets from the work of key scholars on the topic relationships, we hope to hasten socialization of these ideas into nursing into the acute care setting. First, by enabling nurses to reflect on how they might work toward cultivating relationships that are more salutogenic and consistent with the preservation of personhood. Second, by stimulating two distinct but related lines of research enquiry which focus on dyadic and networked relationships with the older person with cognitive impairment in the acute care setting. We also hope to reconcile the schism that has emerged in the literature between preferred approaches to care of the older person with cognitive impairment, that is person-centred care versus relationship-centred care

  18. Using the eSexual Health Clinic to access chlamydia treatment and care via the internet: a qualitative interview study.

    PubMed

    Aicken, Catherine R H; Sutcliffe, Lorna J; Gibbs, Jo; Tickle, Laura J; Hone, Kate; Harding-Esch, Emma M; Mercer, Catherine H; Sonnenberg, Pam; Sadiq, S Tariq; Estcourt, Claudia S; Shahmanesh, Maryam

    2018-06-01

    We developed the eSexual Health Clinic (eSHC), an innovative, complex clinical and public health intervention, embedded within a specialist sexual health service. Patients with genital chlamydia access their results online and are offered medical management via an automated online clinical consultation, leading to antibiotic collection from community pharmacy. A telephone helpline, staffed by Sexual Health Advisers, is available to support patients and direct them to conventional services if appropriate. We sought to understand how patients used this ehealth intervention. Within exploratory studies of the eSHC (2014-2015), we conducted in-depth interviews with a purposive sample of 36 patients diagnosed with chlamydia, who had chosen to use the eSHC (age 18-35, 20 female, 16 male). Thematic analysis was conducted. Participants described choosing to use this ehealth intervention to obtain treatment rapidly, conveniently and privately, within busy lifestyles that hindered clinic access. They described completing the online consultation promptly, discreetly and with ease. The information provided online was considered comprehensive, reassuring and helpful, but some overlooked it in their haste to obtain treatment. Participants generally described being able to collect treatment from pharmacies discreetly and promptly, but for some, poor awareness of the eSHC by pharmacy staff undermined their ability to do this. Those unsuitable for remote management, who were directed to clinic, described frustration and concern about health implications and clinic attendance. However, the helpline was a highly valued source of information, assistance and support. The eSHC is a promising adjunct to traditional care. Its users have high expectations for convenience, speed and privacy, which may be compromised when transitioning from online to face-to-face elements of the eSHC. Managing expectations and improving implementation of the pharmacy process, could improve their experiences

  19. Model-independent limits and constraints on extended theories of gravity from cosmic reconstruction techniques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cruz-Dombriz, Álvaro de la; Dunsby, Peter K.S.; Luongo, Orlando

    The onset of dark energy domination depends on the particular gravitational theory driving the cosmic evolution. Model independent techniques are crucial to test the both the present ΛCDM cosmological paradigm and alternative theories, making the least possible number of assumptions about the Universe. In this paper we investigate whether cosmography is able to distinguish between different gravitational theories, by determining bounds on model parameters for three different extensions of General Relativity, namely quintessence, F (Τ) and f ( R ) gravitational theories. We expand each class of theories in powers of redshift z around the present time, making no additionalmore » assumptions. This procedure is an extension of previous work and can be seen as the most general approach for testing extended theories of gravity through the use of cosmography. In the case of F (Τ) and f ( R ) theories, we show that some assumptions on model parameters often made in previous works are superfluous or even unjustified. We use data from the Union 2.1 supernovae catalogue, baryonic acoustic oscillation data and H ( z ) differential age compilations, which probe cosmology on different scales of the cosmological evolution. We perform a Monte Carlo analysis using a Metropolis-Hastings algorithm with a Gelman-Rubin convergence criterion, reporting 1-σ and 2-σ confidence levels. To do so, we perform two distinct fits, assuming only data within z < 1 first and then without limitations in redshift. We obtain the corresponding numerical intervals in which coefficients span, and find that the data is compatible the ΛCDM limit of all three theories at the 1-σ level, while still compatible with quite a large portion of parameter space. We compare our results to the truncated ΛCDM paradigm, demonstrating that our bounds divert from the expectations of previous works, showing that the permitted regions of coefficients are significantly modified and in general widened with respect

  20. Evaluation of PET and MR datasets in integrated 18F-FDG PET/MRI: A comparison of different MR sequences for whole-body restaging of breast cancer patients.

    PubMed

    Grueneisen, Johannes; Sawicki, Lino Morris; Wetter, Axel; Kirchner, Julian; Kinner, Sonja; Aktas, Bahriye; Forsting, Michael; Ruhlmann, Verena; Umutlu, Lale

    2017-04-01

    To investigate the diagnostic value of different MR sequences and 18F-FDG PET data for whole-body restaging of breast cancer patients utilizing PET/MRI. A total of 36 patients with suspected tumor recurrence of breast cancer based on clinical follow-up or abnormal findings in follow-up examinations (e.g. CT, MRI) were prospectively enrolled in this study. All patients underwent a PET/CT and subsequently an additional PET/MR scan. Two readers were instructed to identify the occurrence of a tumor relapse in subsequent MR and PET/MR readings, utilizing different MR sequence constellations for each session. The diagnostic confidence for the determination of a malignant or benign lesion was qualitatively rated (3-point ordinal scale) for each lesion in the different reading sessions and the lesion conspicuity (4-point ordinal scale) for the three different MR sequences was additionally evaluated. Tumor recurrence was present in 25/36 (69%) patients. All three PET/MRI readings showed a significantly higher accuracy as well as higher confidence levels for the detection of recurrent breast cancer lesions when compared to MRI alone (p<0.05). Furthermore, all three PET/MR sequence constellations showed comparable diagnostic accuracy for the identification of a breast cancer recurrence (p>0.05), yet the highest confidence levels were obtained, when all three MR sequences were used for image interpretation. Moreover, contrast-enhanced T1-weighted VIBE imaging showed significantly higher values for the delineation of malignant and benign lesions when compared to T2w HASTE and diffusion-weighted imaging. Integrated PET/MRI provides superior restaging of breast cancer patients over MRI alone. Facing the need for appropriate and efficient whole-body PET/MR protocols, our results show the feasibility of fast and morphologically adequate PET/MR protocols. However, considering an equivalent accuracy for the detection of breast cancer recurrences in the three PET/MR readings, the

  1. Capacity for Preferences: Respecting Patients with Compromised Decision-Making.

    PubMed

    Wasserman, Jason Adam; Navin, Mark Christopher

    2018-05-01

    important consequences for treatment decisions involving these vulnerable patients. © 2018 The Hastings Center.

  2. Balancing Benefits and Risks of Immortal Data: Participants' Views of Open Consent in the Personal Genome Project.

    PubMed

    Zarate, Oscar A; Brody, Julia Green; Brown, Phil; Ramirez-Andreotta, Mónica D; Perovich, Laura; Matz, Jacob

    2016-01-01

    practices and protocol reviews for big-data research. © 2015 The Hastings Center.

  3. Lake on life support: Evaluating urban lake management measures by using a coupled 1D-modelling approach

    NASA Astrophysics Data System (ADS)

    Ladwig, Robert; Kirillin, Georgiy; Hinkelmann, Reinhard; Hupfer, Michael

    2017-04-01

    Urban surface water systems and especially lakes are heavily stressed and modified systems to comply with water management goals and expectations. In this study we focus on Lake Tegel in Berlin, Germany, as a representative of heavily modified urban lakes. In the 20th century, Lake Tegel received increased loadings of nutrients and leached heavy metals from an upstream sewage farm resulting in severe eutrophication problems. The construction of two upstream treatment plants caused a lowering of nutrient concentrations and a re-oligotrophication of the lake. Additionally, artificial aerators, to keep the hypolimnion oxic, and a lake pipeline, to bypass water for maintaining a minimum discharge, went into operation. Lake Tegel is still heavily used for drinking water extraction by bank filtration. These interacting management measures make the system vulnerable to changing climate conditions and pollutant loads. Past modelling studies have shown the complex hydrodynamics of the lake. Here, we are following a simplified approach by using a less computational time consuming vertical 1D-model to simulate the hydrodynamics and the ecological interactions of the system by coupling the General Lake Model to the Aquatic Ecodynamics Model Library 2. For calibration of the multidimensional parameter space we applied the Covariance Matrix Adaption-Evolution Strategy algorithm. The model is able to sufficiently replicate the vertical field temperature profiles of Lake Tegel as well as to simulate similar concentration ranges of phosphate, dissolved oxygen and nitrate. The calibrated model is used to run an uncertainty analysis by sampling the simulated data within the meaning of the Metropolis-Hastings algorithm. Finally, we are evaluating different scenarios: (1) changing air temperatures, precipitation and wind speed due to effects of climate change, (2) decreased discharges into the lake due to bypassing treated effluents into a near stream instead of Lake Tegel, and (3

  4. SU-E-T-58: A Novel Monte Carlo Photon Transport Simulation Scheme and Its Application in Cone Beam CT Projection Simulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, Y; Southern Medical University, Guangzhou; Tian, Z

    Purpose: Monte Carlo (MC) simulation is an important tool to solve radiotherapy and medical imaging problems. Low computational efficiency hinders its wide applications. Conventionally, MC is performed in a particle-by -particle fashion. The lack of control on particle trajectory is a main cause of low efficiency in some applications. Take cone beam CT (CBCT) projection simulation as an example, significant amount of computations were wasted on transporting photons that do not reach the detector. To solve this problem, we propose an innovative MC simulation scheme with a path-by-path sampling method. Methods: Consider a photon path starting at the x-ray source.more » After going through a set of interactions, it ends at the detector. In the proposed scheme, we sampled an entire photon path each time. Metropolis-Hasting algorithm was employed to accept/reject a sampled path based on a calculated acceptance probability, in order to maintain correct relative probabilities among different paths, which are governed by photon transport physics. We developed a package gMMC on GPU with this new scheme implemented. The performance of gMMC was tested in a sample problem of CBCT projection simulation for a homogeneous object. The results were compared to those obtained using gMCDRR, a GPU-based MC tool with the conventional particle-by-particle simulation scheme. Results: Calculated scattered photon signals in gMMC agreed with those from gMCDRR with a relative difference of 3%. It took 3.1 hr. for gMCDRR to simulate 7.8e11 photons and 246.5 sec for gMMC to simulate 1.4e10 paths. Under this setting, both results attained the same ∼2% statistical uncertainty. Hence, a speed-up factor of ∼45.3 was achieved by this new path-by-path simulation scheme, where all the computations were spent on those photons contributing to the detector signal. Conclusion: We innovatively proposed a novel path-by-path simulation scheme that enabled a significant efficiency enhancement for MC

  5. CMA Announces the 1996 Responsible Care Catalyst Awards Winners

    NASA Astrophysics Data System (ADS)

    1996-06-01

    Eighteen exceptional teachers of science, chemical technology, chemistry, and chemical engineering have been selected to receive a Responsible Care Chemical Manufacturers Association's 1996 Catalyst Award. The Responsible Care Catalyst Awards Program honors individuals who have the ability to inspire students toward careers in chemistry and science-related fields through their excellent teaching ability in and out of the classroom. The program also seeks to draw public attention to the importance of quality chemistry and science teaching at the undergraduate level. Since the award was established in 1957, 502 teachers of science, chemistry, and chemical engineering have been honored. Winners are selected from a wide range of nominations submitted by colleagues, friends, and administrators. All pre-high school, high school, two and four-year college, or university teachers in the United States and Canada are eligible. Each award winner will be presented with a medal and citation. National award winners receive 5,000; regional award winners receive 2,500. National Winners. Martin N. Ackermann, Oberlin College, Oberlin, OH Kenneth R. Jolls, Iowa State University, Ames, IA Suzanne Zobrist Kelly, Warren H. Meeker Elementary School, Ames, IA John V. Kenkel, Southeast Community College, Lincoln, NE George C. Lisensky, Beloit College, Beloit, WI James M. McBride, Yale University, New Haven, CT Marie C. Sherman, Ursuline Academy, St. Louis, MO Dwight D. Sieggreen, Cooke Middle School, Northville, MI Regional Winners Two-Year College. East-Georgianna Whipple-VanPatter, Central Community College, Hastings, NE West-David N. Barkan, Northwest College, Powell, WY High School. East-John Hnatow, Jr., Emmaus High School, Northampton, PA South-Carole Bennett, Gaither High School, Tampa, FL Midwest-Kenneth J. Spengler, Palatine High School, Palatine, IL West-Ruth Rand, Albuquerque, Albuquerque, NM Middle School. East-Thomas P. Kelly, Grandville Public Schools, Grandville, NH

  6. Physics of the spin gap in the S=1/2 Heisenberg antiferromagnet on kagome

    NASA Astrophysics Data System (ADS)

    Tchernyshyov, Oleg

    2009-03-01

    A combination of low spin and strong frustration makes the S=1/2 Heisenberg antiferromagnet on kagome a likely candidate for an unusual ground state and elementary excitations. Exact-diagonalization studies [1] on finite clusters point to a lack of magnetic order in the ground state and to an energy gap of order J/20 for S=1 excitations. The exact nature of the ground state and elementary excitations remains a subject of vigorous debate. Among the proposed ground states are chiral [2] and non-chiral [3] spin liquids and a valence-bond crystal (VBC) [4-5]; spin excitations range from deconfined spinons with a Bose [6] or Fermi statistics [2-3] to magnons [7]. We show that the system behaves as a collection of spinons, quasiparticles with S=1/2 and Fermi statistics, whose motion disturbs valence-bond order. Attraction between spinons, mediated by exchange, binds them into small, massive pairs of S=0 with a binding energy of 0.06 J [8]. The pair formation strongly suppresses the motion of individual spinons and makes the survival of the Singh-Huse VBC plausible. A spin excitation amounts to breaking up a pair into two (nearly) free spinons with S=1. The survival of the VBC is expected to lead to spinon confinement; however, small energy differences between various valence-bond configurations would make the confinement length large. [4pt] [1] Ch. Waldtmann et al., Eur. Phys. J. B 2, 510 (1998).[0pt] [2] J. B. Marston and C. Zeng, J. Appl. Phys. 69, 5962 (1991).[0pt] [3] M. B. Hastings, Phys. Rev. B 63, 014413 (2000).[0pt] [4] P. Nikolic and T. Senthil, Phys. Rev. B 68, 214415 (2003).[0pt] [5] R. R. P. Singh and D. A. Huse, Phys. Rev. B 76, 180407 (2007).[0pt] [6] S. Sachdev, Phys. Rev. B 45, 12377 (1992).[0pt] [7] R. R. P. Singh and D. A. Huse, arXiv:0801.2735. [0pt] [8] Z. Hao and O. Tchernyshyov, the subsequent talk.

  7. A Conceptual Model for the Translation of Bioethics Research and Scholarship.

    PubMed

    Mathews, Debra J H; Hester, D Micah; Kahn, Jeffrey; McGuire, Amy; McKinney, Ross; Meador, Keith; Philpott-Jones, Sean; Youngner, Stuart; Wilfond, Benjamin S

    2016-09-01

    While the bioethics literature demonstrates that the field has spent substantial time and thought over the last four decades on the goals, methods, and desired outcomes for service and training in bioethics, there has been less progress defining the nature and goals of bioethics research and scholarship. This gap makes it difficult both to describe the breadth and depth of these areas of bioethics and, importantly, to gauge their success. However, the gap also presents us with an opportunity to define this scope of work for ourselves and to help shape the broader conversation about the impact of academic research. Because of growing constraints on academic funding, researchers and scholars in many fields are being asked to demonstrate and also forecast the value and impact of their work. To do that, and also to satisfy ourselves that our work has meaningful effect, we must understand how our work can motivate change and how that change can be meaningfully measured. In a field as diverse as bioethics, the pathways to and metrics of change will likewise be diverse. It is therefore critical that any assessment of the impact of bioethics research and scholarship be informed by an understanding of the nature of the work, its goals, and how those goals can and ought to be furthered. In this paper, we propose a conceptual model that connects individual bioethics projects to the broader goals of scholarship, describing the translation of research and scholarly output into changes in thinking, practice, and policy. One of the key implications of the model is that impact in bioethics is generally the result of a collection of projects rather than of any single piece of research or scholarship. Our goal is to lay the groundwork for a thoroughgoing conversation about bioethics research and scholarship that will advance and shape the important conversation about their impact. © 2016 The Hastings Center.

  8. Does speed matter? The impact of operative time on outcome in laparoscopic surgery

    PubMed Central

    Jackson, Timothy D.; Wannares, Jeffrey J.; Lancaster, R. Todd; Rattner, David W.

    2012-01-01

    Introduction Controversy exists concerning the importance of operative time on patient outcomes. It is unclear whether faster is better or haste makes waste or similarly whether slower procedures represent a safe, meticulous approach or inexperienced dawdling. The objective of the present study was to determine the effect of operative time on 30-day outcomes in laparoscopic surgery. Methods Patients who underwent laparoscopic general surgery procedures (colectomy, cholecystectomy, Nissen fundoplication, inguinal hernia, and gastric bypass) from the ACS-NSQIP 2005–2008 participant use file were identified. Exclusion criteria were defined a priori to identify same-day admission, elective procedures. Operative time was divided into deciles and summary statistics were analyzed. Univariate analyses using a Cochran-Armitage test for trend were completed. The effect of operative time on 30-day morbidity was further analyzed for each procedure type using multivariate regression controlling for case complexity and additional patient factors. Patients within the highest deciles were excluded to reduce outlier effect. Results A total of 76,748 elective general surgical patients who underwent laparoscopic procedures were analyzed. Univariate analyses of deciles of operative time demonstrated a statistically significant trend (p \\ 0.0001) toward increasing odds of complications with increasing operative time for laparoscopic colectomy (n = 10,135), cholecystectomy (n = 37,407), Nissen fundoplication (n = 4,934), and gastric bypass (n = 17,842). The trend was not found to be significant for laparoscopic inguinal hernia repair (n = 6,430; p = 0.14). Multivariate modeling revealed the effect of operative time to remain significant after controlling for additional patient factors. Conclusion Increasing operative time was associated with increased odds of complications and, therefore, it appears that speed may matter in laparoscopic surgery. These analyses are limited in their

  9. Applied Mathematics in EM Studies with Special Emphasis on an Uncertainty Quantification and 3-D Integral Equation Modelling

    NASA Astrophysics Data System (ADS)

    Pankratov, Oleg; Kuvshinov, Alexey

    2016-01-01

    Despite impressive progress in the development and application of electromagnetic (EM) deterministic inverse schemes to map the 3-D distribution of electrical conductivity within the Earth, there is one question which remains poorly addressed—uncertainty quantification of the recovered conductivity models. Apparently, only an inversion based on a statistical approach provides a systematic framework to quantify such uncertainties. The Metropolis-Hastings (M-H) algorithm is the most popular technique for sampling the posterior probability distribution that describes the solution of the statistical inverse problem. However, all statistical inverse schemes require an enormous amount of forward simulations and thus appear to be extremely demanding computationally, if not prohibitive, if a 3-D set up is invoked. This urges development of fast and scalable 3-D modelling codes which can run large-scale 3-D models of practical interest for fractions of a second on high-performance multi-core platforms. But, even with these codes, the challenge for M-H methods is to construct proposal functions that simultaneously provide a good approximation of the target density function while being inexpensive to be sampled. In this paper we address both of these issues. First we introduce a variant of the M-H method which uses information about the local gradient and Hessian of the penalty function. This, in particular, allows us to exploit adjoint-based machinery that has been instrumental for the fast solution of deterministic inverse problems. We explain why this modification of M-H significantly accelerates sampling of the posterior probability distribution. In addition we show how Hessian handling (inverse, square root) can be made practicable by a low-rank approximation using the Lanczos algorithm. Ultimately we discuss uncertainty analysis based on stochastic inversion results. In addition, we demonstrate how this analysis can be performed within a deterministic approach. In the

  10. Topics in Bayesian Hierarchical Modeling and its Monte Carlo Computations

    NASA Astrophysics Data System (ADS)

    Tak, Hyung Suk

    The first chapter addresses a Beta-Binomial-Logit model that is a Beta-Binomial conjugate hierarchical model with covariate information incorporated via a logistic regression. Various researchers in the literature have unknowingly used improper posterior distributions or have given incorrect statements about posterior propriety because checking posterior propriety can be challenging due to the complicated functional form of a Beta-Binomial-Logit model. We derive data-dependent necessary and sufficient conditions for posterior propriety within a class of hyper-prior distributions that encompass those used in previous studies. Frequency coverage properties of several hyper-prior distributions are also investigated to see when and whether Bayesian interval estimates of random effects meet their nominal confidence levels. The second chapter deals with a time delay estimation problem in astrophysics. When the gravitational field of an intervening galaxy between a quasar and the Earth is strong enough to split light into two or more images, the time delay is defined as the difference between their travel times. The time delay can be used to constrain cosmological parameters and can be inferred from the time series of brightness data of each image. To estimate the time delay, we construct a Gaussian hierarchical model based on a state-space representation for irregularly observed time series generated by a latent continuous-time Ornstein-Uhlenbeck process. Our Bayesian approach jointly infers model parameters via a Gibbs sampler. We also introduce a profile likelihood of the time delay as an approximation of its marginal posterior distribution. The last chapter specifies a repelling-attracting Metropolis algorithm, a new Markov chain Monte Carlo method to explore multi-modal distributions in a simple and fast manner. This algorithm is essentially a Metropolis-Hastings algorithm with a proposal that consists of a downhill move in density that aims to make local modes

  11. MR enterography in nonresponsive adult celiac disease: Correlation with endoscopic, pathologic, serologic, and genetic features.

    PubMed

    Radmard, Amir Reza; Hashemi Taheri, Amir Pejman; Salehian Nik, Elham; Kooraki, Soheil; Kolahdoozan, Shadi; Mirminachi, Babak; Sotoudeh, Masoud; Ekhlasi, Golnaz; Malekzadeh, Reza; Shahbazkhani, Bijan

    2017-10-01

    To assess small bowel abnormalities on magnetic resonance enterography (MRE) in adult patients with nonresponsive celiac disease (CD) and investigate their associations with endoscopic, histopathologic, serologic, and genetic features. This prospective study was carried out between September 2012 and August 2013. After approval by the Ethics Committee of our institution, informed consent was acquired from all participants. Forty consecutive patients with nonresponsive CD, aged 17-76 years, underwent MRE using a 1.5T unit. Sequences included T 2 -HASTE, True-FISP, pre- and postcontrast VIBE to assess the quantitative (number of ileal and jejunal folds) and qualitative (fold pattern abnormalities, mural thickening, increased enhancement, bowel dilatation, or intussusception) measures. Endoscopic manifestations were categorized as normal/mild vs. severe. Histopathological results were divided into mild and severe. Genotyping of HLA-DQ2 and DQ8 was performed. Serum levels of tissue-transglutaminase, endomysial, and gliadin antibodies were also determined. Logistic regression analysis and receiver operating characteristic (ROC) curve were used. Twenty-nine (72.5%) cases showed abnormal MRE. Reversed jejunoileal fold pattern had significant association with severe endoscopic (odds ratio [OR] = 8.38, 95% confidence interval [CI] 1.73-40.5) and pathologic features (OR = 7.36, 95% CI 1.33-40.54). An increased number of ileal folds/inch was significantly associated with severe MARSH score and positive HLA-DQ8. (P < 0.001 and P = 0.026, respectively). Ileal fold number had the highest areas under the curve for prediction of severe endoscopic (AUC: 0.75, P = 0.009) and pathologic (AUC: 0.84, P < 0.001) findings and positive anti-transglutaminase antibody (AUC: 0.85, P = 0.027). Fold pattern reversal on MRE is highly associated with endoscopic and pathologic features of refractory celiac disease (RCD). Increased ileal folds showed higher correlation with endoscopic

  12. Model parameter estimations from residual gravity anomalies due to simple-shaped sources using Differential Evolution Algorithm

    NASA Astrophysics Data System (ADS)

    Ekinci, Yunus Levent; Balkaya, Çağlayan; Göktürkler, Gökhan; Turan, Seçil

    2016-06-01

    An efficient approach to estimate model parameters from residual gravity data based on differential evolution (DE), a stochastic vector-based metaheuristic algorithm, has been presented. We have showed the applicability and effectiveness of this algorithm on both synthetic and field anomalies. According to our knowledge, this is a first attempt of applying DE for the parameter estimations of residual gravity anomalies due to isolated causative sources embedded in the subsurface. The model parameters dealt with here are the amplitude coefficient (A), the depth and exact origin of causative source (zo and xo, respectively) and the shape factors (q and ƞ). The error energy maps generated for some parameter pairs have successfully revealed the nature of the parameter estimation problem under consideration. Noise-free and noisy synthetic single gravity anomalies have been evaluated with success via DE/best/1/bin, which is a widely used strategy in DE. Additionally some complicated gravity anomalies caused by multiple source bodies have been considered, and the results obtained have showed the efficiency of the algorithm. Then using the strategy applied in synthetic examples some field anomalies observed for various mineral explorations such as a chromite deposit (Camaguey district, Cuba), a manganese deposit (Nagpur, India) and a base metal sulphide deposit (Quebec, Canada) have been considered to estimate the model parameters of the ore bodies. Applications have exhibited that the obtained results such as the depths and shapes of the ore bodies are quite consistent with those published in the literature. Uncertainty in the solutions obtained from DE algorithm has been also investigated by Metropolis-Hastings (M-H) sampling algorithm based on simulated annealing without cooling schedule. Based on the resulting histogram reconstructions of both synthetic and field data examples the algorithm has provided reliable parameter estimations being within the sampling limits of

  13. Advanced Large Scale Cross Domain Temporal Topic Modeling Algorithms to Infer the Influence of Recent Research on IPCC Assessment Reports

    NASA Astrophysics Data System (ADS)

    Sleeman, J.; Halem, M.; Finin, T.; Cane, M. A.

    2016-12-01

    topics, we establish which chapter-citation pairs are most similar. We will perform posterior inferences based on Hastings -Metropolis simulated annealing MCMC algorithm to infer, from the evolution of topics starting from AR1 to AR4, assertions of topics for AR5 and potentially AR6.

  14. Epigenetics in the Neoliberal "Regime of Truth": A Biopolitical Perspective on Knowledge Translation.

    PubMed

    Dupras, Charles; Ravitsky, Vardit

    2016-01-01

    called "personalized" or "precision" medicine. In addition, we argue that an overemphasized clinical translation of epigenetics may further reinforce this biopolitical landscape through four processes closely related to neoliberal pathways of thinking: the internalization and isolation (aspects of liberal individualism) of socioenvironmental determinants of health and increased opportunities for commodification and technologicalization (aspects of economic liberalism) of health care interventions. © 2015 The Hastings Center.

  15. Statistical Analysis of CO 2 Exposed Wells to Predict Long Term Leakage through the Development of an Integrated Neural-Genetic Algorithm

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guo, Boyun; Duguid, Andrew; Nygaard, Ronar

    The objective of this project is to develop a computerized statistical model with the Integrated Neural-Genetic Algorithm (INGA) for predicting the probability of long-term leak of wells in CO 2 sequestration operations. This object has been accomplished by conducting research in three phases: 1) data mining of CO 2-explosed wells, 2) INGA computer model development, and 3) evaluation of the predictive performance of the computer model with data from field tests. Data mining was conducted for 510 wells in two CO 2 sequestration projects in the Texas Gulf Coast region. They are the Hasting West field and Oyster Bayou fieldmore » in the Southern Texas. Missing wellbore integrity data were estimated using an analytical and Finite Element Method (FEM) model. The INGA was first tested for performances of convergence and computing efficiency with the obtained data set of high dimension. It was concluded that the INGA can handle the gathered data set with good accuracy and reasonable computing time after a reduction of dimension with a grouping mechanism. A computerized statistical model with the INGA was then developed based on data pre-processing and grouping. Comprehensive training and testing of the model were carried out to ensure that the model is accurate and efficient enough for predicting the probability of long-term leak of wells in CO 2 sequestration operations. The Cranfield in the southern Mississippi was select as the test site. Observation wells CFU31F2 and CFU31F3 were used for pressure-testing, formation-logging, and cement-sampling. Tools run in the wells include Isolation Scanner, Slim Cement Mapping Tool (SCMT), Cased Hole Formation Dynamics Tester (CHDT), and Mechanical Sidewall Coring Tool (MSCT). Analyses of the obtained data indicate no leak of CO 2 cross the cap zone while it is evident that the well cement sheath was invaded by the CO 2 from the storage zone. This observation is consistent with the result predicted by the INGA model which

  16. Near-optimal alternative generation using modified hit-and-run sampling for non-linear, non-convex problems

    NASA Astrophysics Data System (ADS)

    Rosenberg, D. E.; Alafifi, A.

    2016-12-01

    Water resources systems analysis often focuses on finding optimal solutions. Yet an optimal solution is optimal only for the modelled issues and managers often seek near-optimal alternatives that address un-modelled objectives, preferences, limits, uncertainties, and other issues. Early on, Modelling to Generate Alternatives (MGA) formalized near-optimal as the region comprising the original problem constraints plus a new constraint that allowed performance within a specified tolerance of the optimal objective function value. MGA identified a few maximally-different alternatives from the near-optimal region. Subsequent work applied Markov Chain Monte Carlo (MCMC) sampling to generate a larger number of alternatives that span the near-optimal region of linear problems or select portions for non-linear problems. We extend the MCMC Hit-And-Run method to generate alternatives that span the full extent of the near-optimal region for non-linear, non-convex problems. First, start at a feasible hit point within the near-optimal region, then run a random distance in a random direction to a new hit point. Next, repeat until generating the desired number of alternatives. The key step at each iterate is to run a random distance along the line in the specified direction to a new hit point. If linear equity constraints exist, we construct an orthogonal basis and use a null space transformation to confine hits and runs to a lower-dimensional space. Linear inequity constraints define the convex bounds on the line that runs through the current hit point in the specified direction. We then use slice sampling to identify a new hit point along the line within bounds defined by the non-linear inequity constraints. This technique is computationally efficient compared to prior near-optimal alternative generation techniques such MGA, MCMC Metropolis-Hastings, evolutionary, or firefly algorithms because search at each iteration is confined to the hit line, the algorithm can move in one

  17. An update on the "empirical turn" in bioethics: analysis of empirical research in nine bioethics journals.

    PubMed

    Wangmo, Tenzin; Hauri, Sirin; Gennet, Eloise; Anane-Sarpong, Evelyn; Provoost, Veerle; Elger, Bernice S

    2018-02-07

    A review of literature published a decade ago noted a significant increase in empirical papers across nine bioethics journals. This study provides an update on the presence of empirical papers in the same nine journals. It first evaluates whether the empirical trend is continuing as noted in the previous study, and second, how it is changing, that is, what are the characteristics of the empirical works published in these nine bioethics journals. A review of the same nine journals (Bioethics; Journal of Medical Ethics; Journal of Clinical Ethics; Nursing Ethics; Cambridge Quarterly of Healthcare Ethics; Hastings Center Report; Theoretical Medicine and Bioethics; Christian Bioethics; and Kennedy Institute of Ethics Journal) was conducted for a 12-year period from 2004 to 2015. Data obtained was analysed descriptively and using a non-parametric Chi-square test. Of the total number of original papers (N = 5567) published in the nine bioethics journals, 18.1% (n = 1007) collected and analysed empirical data. Journal of Medical Ethics and Nursing Ethics led the empirical publications, accounting for 89.4% of all empirical papers. The former published significantly more quantitative papers than qualitative, whereas the latter published more qualitative papers. Our analysis reveals no significant difference (χ2 = 2.857; p = 0.091) between the proportion of empirical papers published in 2004-2009 and 2010-2015. However, the increasing empirical trend has continued in these journals with the proportion of empirical papers increasing from 14.9% in 2004 to 17.8% in 2015. This study presents the current state of affairs regarding empirical research published nine bioethics journals. In the quarter century of data that is available about the nine bioethics journals studied in two reviews, the proportion of empirical publications continues to increase, signifying a trend towards empirical research in bioethics. The growing volume is mainly attributable to two

  18. The environment of ageing.

    PubMed Central

    Tinker, A

    1997-01-01

    The issue of housing and the wider environment for an ageing population is one where there are many unanswered questions. In this paper a number of key issues are discussed and for each of these the focus is on three aspects. These are the current situation, its reasonableness and what research is needed in order to make decisions about policy and practice. The first three issues relate to the profile of older people themselves and the importance of home to them. The changing profile of older people is not just about an ageing population but also about the growing prominence of those with dementia, women, people from black and ethnic minority groups and one person households, yet little is known about the type of housing which should be provided. Of equal concern is the widening gap between those with a high standard of living (including housing) and those with a low standard of living. The importance of home to older people means that research must focus on how people can be enabled to remain there, and also on the costs, financial and otherwise, to carers and to society. The next three issues relate to the type of housing older people live in and moves in later life. The startling change in the tenure pattern with a growth of owner occupation brings problems as does the decline in social housing. The advantages and disadvantages of the different types of housing--mainstream and specialized--for older people are relatively well known. However the balance between the two needs more research as does that on retirement communities. While it is well known that there are peaks of migration in old age and that moves are often made in haste, little is known about the process of decision making. The final two topics concern links between housing and other aspects of older people's lives. On health more research is needed on temperature, mortality and morbidity, homelessness and accidents and especially on links between services. These topics have implications for planning

  19. Facts, values, and Attention-Deficit Hyperactivity Disorder (ADHD): an update on the controversies

    PubMed Central

    Parens, Erik; Johnston, Josephine

    2009-01-01

    The Hastings Center, a bioethics research institute, is holding a series of 5 workshops to examine the controversies surrounding the use of medication to treat emotional and behavioral disturbances in children. These workshops bring together clinicians, researchers, scholars, and advocates with diverse perspectives and from diverse fields. Our first commentary in CAPMH, which grew out of our first workshop, explained our method and explored the controversies in general. This commentary, which grows out of our second workshop, explains why informed people can disagree about ADHD diagnosis and treatment. Based on what workshop participants said and our understanding of the literature, we make 8 points. (1) The ADHD label is based on the interpretation of a heterogeneous set of symptoms that cause impairment. (2) Because symptoms and impairments are dimensional, there is an inevitable "zone of ambiguity," which reasonable people will interpret differently. (3) Many other variables, from different systems and tools of diagnosis to different parenting styles and expectations, also help explain why behaviors associated with ADHD can be interpreted differently. (4) Because people hold competing views about the proper goals of psychiatry and parenting, some people will be more, and others less, concerned about treating children in the zone of ambiguity. (5) To recognize that nature has written no bright line between impaired and unimpaired children, and that it is the responsibility of humans to choose who should receive a diagnosis, does not diminish the significance of ADHD. (6) Once ADHD is diagnosed, the facts surrounding the most effective treatment are complicated and incomplete; contrary to some popular wisdom, behavioral treatments, alone or in combination with low doses of medication, can be effective in the long-term reduction of core ADHD symptoms and at improving many aspects of overall functioning. (7) Especially when a child occupies the zone of ambiguity

  20. A reversible-jump Markov chain Monte Carlo algorithm for 1D inversion of magnetotelluric data

    NASA Astrophysics Data System (ADS)

    Mandolesi, Eric; Ogaya, Xenia; Campanyà, Joan; Piana Agostinetti, Nicola

    2018-04-01

    This paper presents a new computer code developed to solve the 1D magnetotelluric (MT) inverse problem using a Bayesian trans-dimensional Markov chain Monte Carlo algorithm. MT data are sensitive to the depth-distribution of rock electric conductivity (or its reciprocal, resistivity). The solution provided is a probability distribution - the so-called posterior probability distribution (PPD) for the conductivity at depth, together with the PPD of the interface depths. The PPD is sampled via a reversible-jump Markov Chain Monte Carlo (rjMcMC) algorithm, using a modified Metropolis-Hastings (MH) rule to accept or discard candidate models along the chains. As the optimal parameterization for the inversion process is generally unknown a trans-dimensional approach is used to allow the dataset itself to indicate the most probable number of parameters needed to sample the PPD. The algorithm is tested against two simulated datasets and a set of MT data acquired in the Clare Basin (County Clare, Ireland). For the simulated datasets the correct number of conductive layers at depth and the associated electrical conductivity values is retrieved, together with reasonable estimates of the uncertainties on the investigated parameters. Results from the inversion of field measurements are compared with results obtained using a deterministic method and with well-log data from a nearby borehole. The PPD is in good agreement with the well-log data, showing as a main structure a high conductive layer associated with the Clare Shale formation. In this study, we demonstrate that our new code go beyond algorithms developend using a linear inversion scheme, as it can be used: (1) to by-pass the subjective choices in the 1D parameterizations, i.e. the number of horizontal layers in the 1D parameterization, and (2) to estimate realistic uncertainties on the retrieved parameters. The algorithm is implemented using a simple MPI approach, where independent chains run on isolated CPU, to take