Large Polyglutamine Repeats Cause Muscle Degeneration in SCA17 Mice

PubMed Central

Huang, Shanshan; Yang, Su; Guo, Jifeng; Yan, Sen; Gaertig, Marta A.; Li, Shihua; Li, Xiao-Jiang

2015-01-01

SUMMARY In polyglutamine (polyQ) diseases, large polyQ repeats cause juvenile cases with different symptoms than adult-onset patients, who carry smaller expanded polyQ repeats. The mechanisms behind the differential pathology mediated by different polyQ repeat lengths remain unknown. By studying knock-in mouse models of spinal cerebellar ataxia-17 (SCA17), we found that a large polyQ (105 glutamines) in the TATA box-binding protein (TBP) preferentially causes muscle degeneration and reduces the expression of muscle-specific genes. Direct expression of TBP with different polyQ repeats in mouse muscle revealed that muscle degeneration is mediated only by the large polyQ repeats. Different polyQ repeats differentially alter TBP’s interaction with neuronal and muscle-specific transcription factors. As a result, the large polyQ repeat decreases the association of MyoD with TBP and DNA promoters. Our findings suggest that specific alterations in protein interactions by large polyQ repeats may account for the unique pathology in juvenile polyQ diseases. PMID:26387956

Volatility return intervals analysis of the Japanese market

NASA Astrophysics Data System (ADS)

Jung, W.-S.; Wang, F. Z.; Havlin, S.; Kaizoji, T.; Moon, H.-T.; Stanley, H. E.

2008-03-01

We investigate scaling and memory effects in return intervals between price volatilities above a certain threshold q for the Japanese stock market using daily and intraday data sets. We find that the distribution of return intervals can be approximated by a scaling function that depends only on the ratio between the return interval τ and its mean <τ>. We also find memory effects such that a large (or small) return interval follows a large (or small) interval by investigating the conditional distribution and mean return interval. The results are similar to previous studies of other markets and indicate that similar statistical features appear in different financial markets. We also compare our results between the period before and after the big crash at the end of 1989. We find that scaling and memory effects of the return intervals show similar features although the statistical properties of the returns are different.

Individual Differences in Susceptibility to Inattentional Blindness

ERIC Educational Resources Information Center

Seegmiller, Janelle K.; Watson, Jason M.; Strayer, David L.

2011-01-01

Inattentional blindness refers to the finding that people do not always see what appears in their gaze. Though inattentional blindness affects large percentages of people, it is unclear if there are individual differences in susceptibility. The present study addressed whether individual differences in attentional control, as reflected by…

Individual Differences, Intelligence, and Behavior Analysis

ERIC Educational Resources Information Center

Williams, Ben; Myerson, Joel; Hale, Sandra

2008-01-01

Despite its avowed goal of understanding individual behavior, the field of behavior analysis has largely ignored the determinants of consistent differences in level of performance among individuals. The present article discusses major findings in the study of individual differences in intelligence from the conceptual framework of a functional…

Tropospheric transport differences between models using the same large-scale meteorological fields

NASA Astrophysics Data System (ADS)

Orbe, Clara; Waugh, Darryn W.; Yang, Huang; Lamarque, Jean-Francois; Tilmes, Simone; Kinnison, Douglas E.

2017-01-01

The transport of chemicals is a major uncertainty in the modeling of tropospheric composition. A common approach is to transport gases using the winds from meteorological analyses, either using them directly in a chemical transport model or by constraining the flow in a general circulation model. Here we compare the transport of idealized tracers in several different models that use the same meteorological fields taken from Modern-Era Retrospective analysis for Research and Applications (MERRA). We show that, even though the models use the same meteorological fields, there are substantial differences in their global-scale tropospheric transport related to large differences in parameterized convection between the simulations. Furthermore, we find that the transport differences between simulations constrained with the same-large scale flow are larger than differences between free-running simulations, which have differing large-scale flow but much more similar convective mass fluxes. Our results indicate that more attention needs to be paid to convective parameterizations in order to understand large-scale tropospheric transport in models, particularly in simulations constrained with analyzed winds.

Morphological Differences Between Seyfert Hosts and Normal Galaxies

NASA Astrophysics Data System (ADS)

Shlosman, Isaac

Using new sub-arcsecond resolution imaging we compare large-scale stellar bar fraction in CfA sample of Seyferts and a closely matched control sample of normal galaxies. We find a difference between the samples on the 2.5σ level. We further compare the axial ratios of bars in all available samples quoted in the literature and find a deficiency of small axial ratio bars in Seyferts compared to normal galaxies.

Geographic Differences in the Earnings of Economics Majors

ERIC Educational Resources Information Center

Winters, John V.; Xu, Weineng

2014-01-01

Economics has been shown to be a relatively high-earning college major, but geographic differences in earnings have been largely overlooked. The authors of this article use the American Community Survey to examine geographic differences in both absolute earnings and relative earnings for economics majors. They find that there are substantial…

Individual Differences and Learning Contexts: A Self-Regulated Learning Perspective

ERIC Educational Resources Information Center

Ben-Eliyahu, Adar

2017-01-01

This article examines how individual differences (giftedness) interact with learning contexts (favorite versus least favorite courses) to influence learning processes and outcomes. The findings show that gifted and typically developing students differ solely in their expectancies for success and grades among a large variety of measures, including…

Methods for Synthesizing Findings on Moderation Effects Across Multiple Randomized Trials

PubMed Central

Brown, C Hendricks; Sloboda, Zili; Faggiano, Fabrizio; Teasdale, Brent; Keller, Ferdinand; Burkhart, Gregor; Vigna-Taglianti, Federica; Howe, George; Masyn, Katherine; Wang, Wei; Muthén, Bengt; Stephens, Peggy; Grey, Scott; Perrino, Tatiana

2011-01-01

This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis, and parallel analyses, sharing a large advantage over traditional methods available in meta-analysis. We present a broad class of analytic models to examine moderation effects across trials that can be used to assess their overall effect and explain sources of heterogeneity, and present ways to disentangle differences across trials due to individual differences, contextual level differences, intervention, and trial design. PMID:21360061

Methods for synthesizing findings on moderation effects across multiple randomized trials.

PubMed

Brown, C Hendricks; Sloboda, Zili; Faggiano, Fabrizio; Teasdale, Brent; Keller, Ferdinand; Burkhart, Gregor; Vigna-Taglianti, Federica; Howe, George; Masyn, Katherine; Wang, Wei; Muthén, Bengt; Stephens, Peggy; Grey, Scott; Perrino, Tatiana

2013-04-01

This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis and parallel analyses, sharing a large advantage over traditional methods available in meta-analysis. We present a broad class of analytic models to examine moderation effects across trials that can be used to assess their overall effect and explain sources of heterogeneity, and present ways to disentangle differences across trials due to individual differences, contextual level differences, intervention, and trial design.

Homeless Students and Academic Achievement: Evidence from a Large Urban Area

ERIC Educational Resources Information Center

Tobin, Kerri J.

2016-01-01

Child homelessness has recently reached levels unprecedented in the United States since the Great Depression. Contemporary research has attempted to isolate the effects of homelessness on education, with mixed results. This study reports results from a study in one large urban area and finds that there is no meaningful difference in achievement…

How much a galaxy knows about its large-scale environment?: An information theoretic perspective

NASA Astrophysics Data System (ADS)

Pandey, Biswajit; Sarkar, Suman

2017-05-01

The small-scale environment characterized by the local density is known to play a crucial role in deciding the galaxy properties but the role of large-scale environment on galaxy formation and evolution still remain a less clear issue. We propose an information theoretic framework to investigate the influence of large-scale environment on galaxy properties and apply it to the data from the Galaxy Zoo project that provides the visual morphological classifications of ˜1 million galaxies from the Sloan Digital Sky Survey. We find a non-zero mutual information between morphology and environment that decreases with increasing length-scales but persists throughout the entire length-scales probed. We estimate the conditional mutual information and the interaction information between morphology and environment by conditioning the environment on different length-scales and find a synergic interaction between them that operates up to at least a length-scales of ˜30 h-1 Mpc. Our analysis indicates that these interactions largely arise due to the mutual information shared between the environments on different length-scales.

An audit of manufacturers' implementation of reconstruction filters in single-photon emission computed tomography.

PubMed

Lawson, Richard S; White, Duncan; Cade, Sarah C; Hall, David O; Kenny, Bob; Knight, Andy; Livieratos, Lefteris; Nijran, Kuldip

2013-08-01

The Nuclear Medicine Software Quality Group of the Institute of Physics and Engineering in Medicine has conducted an audit to compare the ways in which different manufacturers implement the filters used in single-photon emission computed tomography. The aim of the audit was to identify differences between manufacturers' implementations of the same filter and to find means for converting parameters between systems. Computer-generated data representing projection images of an ideal test object were processed using seven different commercial nuclear medicine systems. Images were reconstructed using filtered back projection and a Butter worth filter with three different cutoff frequencies and three different orders. The audit found large variations between the frequency-response curves of what were ostensibly the same filters on different systems. The differences were greater than could be explained simply by different Butter worth formulae. Measured cutoff frequencies varied between 40 and 180% of that expected. There was also occasional confusion with respect to frequency units. The audit concluded that the practical implementation of filtering, such as the size of the kernel, has a profound effect on the results, producing large differences between systems. Nevertheless, this work shows how users can quantify the frequency response of their own systems so that it will be possible to compare two systems in order to find filter parameters on each that produce equivalent results. These findings will also make it easier for users to replicate filters similar to other published results, even if they are using a different computer system.

Differences in Spending in School Districts across Geographic Locales in Minnesota. Summary. Issues & Answers. REL 2012-No. 124

ERIC Educational Resources Information Center

Wan, Yinmei; Norbury, Heather; Molefe, Ayrin C.; Gerdeman, R. Dean; Meyers, Coby V.; Burke, Matthew

2012-01-01

This study examines differences in spending in school districts across geographic locales in Minnesota and factors that might contribute to these differences. The study finds that district spending per student in 2008/09 varied across locale types in Minnesota. These differences are largely accounted for by differences in regional characteristics…

An Analysis of College Students' Self-Disclosure Behaviors on the Internet

ERIC Educational Resources Information Center

Punyanunt-Carter, Narissra Maria

2006-01-01

Four hundred and ninety-two undergraduate students at a large Midwestern university completed a 35 item questionnaire designed to assess self-disclosure behaviors on the Internet. Findings revealed that males and females have different perceptions about their self-disclosure behaviors on the Internet. In addition, findings showed that college…

Parents' Views on Mixed and Single-Sex Secondary Schools.

ERIC Educational Resources Information Center

West, Anne; Hunter, Jay

1993-01-01

Reports on two studies of British parental attitudes toward coeducational and single-sex secondary schools. Finds few differences between the parents of primary school girls and boys who will attend secondary schools in the future. Also finds a large majority of boys' parents believe that social advantages accrue for boys educated with girls. (CFR)

A false sense of security? Can tiered approach be trusted to accurately classify immunogenicity samples?

PubMed

Jaki, Thomas; Allacher, Peter; Horling, Frank

2016-09-05

Detecting and characterizing of anti-drug antibodies (ADA) against a protein therapeutic are crucially important to monitor the unwanted immune response. Usually a multi-tiered approach that initially rapidly screens for positive samples that are subsequently confirmed in a separate assay is employed for testing of patient samples for ADA activity. In this manuscript we evaluate the ability of different methods used to classify subject with screening and competition based confirmatory assays. We find that for the overall performance of the multi-stage process the method used for confirmation is most important where a t-test is best when differences are moderate to large. Moreover we find that, when differences between positive and negative samples are not sufficiently large, using a competition based confirmation step does yield poor classification of positive samples. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Effects of SO(10)-inspired scalar non-universality on the MSSM parameter space at large tanβ

NASA Astrophysics Data System (ADS)

Ramage, M. R.

2005-08-01

We analyze the parameter space of the ( μ>0, A=0) CMSSM at large tanβ with a small degree of non-universality originating from D-terms and Higgs-sfermion splitting inspired by SO(10) GUT models. The effects of such non-universalities on the sparticle spectrum and observables such as (, B(b→Xγ), the SUSY threshold corrections to the bottom mass and Ωh are examined in detail and the consequences for the allowed parameter space of the model are investigated. We find that even small deviations to universality can result in large qualitative differences compared to the universal case; for certain values of the parameters, we find, even at low m and m, that radiative electroweak symmetry breaking fails as a consequence of either |<0 or mA2<0. We find particularly large departures from the mSugra case for the neutralino relic density, which is sensitive to significant changes in the position and shape of the A resonance and a substantial increase in the Higgsino component of the LSP. However, we find that the corrections to the bottom mass are not sufficient to allow for Yukawa unification.

Finding Information in (Very Large) Digital Libraries: A Deep Log Approach to Determining Differences in Use According to Method of Access

ERIC Educational Resources Information Center

Nicholas, David; Huntington, Paul; Jamali, Hamid R.; Tenopir, Carol

2006-01-01

This report presents the early findings of an exploratory deep log analysis (DLA) of journal usage on OhioLINK, reporting on the information seeking methods of users. Compared to the users who sought information by browsing journals, those who conducted searches to find information and articles tended to record longer session times and viewed more…

Economic impacts of climate change on agriculture: a comparison of process-based and statistical yield models

NASA Astrophysics Data System (ADS)

Moore, Frances C.; Baldos, Uris Lantz C.; Hertel, Thomas

2017-06-01

A large number of studies have been published examining the implications of climate change for agricultural productivity that, broadly speaking, can be divided into process-based modeling and statistical approaches. Despite a general perception that results from these methods differ substantially, there have been few direct comparisons. Here we use a data-base of yield impact studies compiled for the IPCC Fifth Assessment Report (Porter et al 2014) to systematically compare results from process-based and empirical studies. Controlling for differences in representation of CO2 fertilization between the two methods, we find little evidence for differences in the yield response to warming. The magnitude of CO2 fertilization is instead a much larger source of uncertainty. Based on this set of impact results, we find a very limited potential for on-farm adaptation to reduce yield impacts. We use the Global Trade Analysis Project (GTAP) global economic model to estimate welfare consequences of yield changes and find negligible welfare changes for warming of 1 °C-2 °C if CO2 fertilization is included and large negative effects on welfare without CO2. Uncertainty bounds on welfare changes are highly asymmetric, showing substantial probability of large declines in welfare for warming of 2 °C-3 °C even including the CO2 fertilization effect.

Gender Differences in Faculty Productivity, Satisfaction, and Salary: What Really Separates Us?

ERIC Educational Resources Information Center

Hagedorn, Linda Serra

Gender differences in faculty productivity, satisfaction, and salary were studied using 2 large datasets, the 1999 Higher Education Research Institute Faculty Survey (n=55,081) and the 1993 National Study of Postsecondary Faculty (n=25,780). Findings show very little evidence of gender differences in productivity, especially at the lower…

Earning Differences by Major Field of Study: Evidence from Three Cohorts of Recent Canadian Graduates.

ERIC Educational Resources Information Center

Finnie, Ross; Frenette, Marc

2003-01-01

Analysis of earnings differences by major field of study of three cohorts of graduates (1982, 1986, 1990) with bachelors' degrees from Canadian postsecondary institutions. Finds that earnings differences are large and statistically significant. The patterns are relatively consistent for the three cohorts and for male and female graduates, 2 and 5…

A Comprehensive Analysis of Multiscale Field-Aligned Currents: Characteristics, Controlling Parameters, and Relationships

NASA Astrophysics Data System (ADS)

McGranaghan, Ryan M.; Mannucci, Anthony J.; Forsyth, Colin

2017-12-01

We explore the characteristics, controlling parameters, and relationships of multiscale field-aligned currents (FACs) using a rigorous, comprehensive, and cross-platform analysis. Our unique approach combines FAC data from the Swarm satellites and the Advanced Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) to create a database of small-scale (˜10-150 km, <1° latitudinal width), mesoscale (˜150-250 km, 1-2° latitudinal width), and large-scale (>250 km) FACs. We examine these data for the repeatable behavior of FACs across scales (i.e., the characteristics), the dependence on the interplanetary magnetic field orientation, and the degree to which each scale "departs" from nominal large-scale specification. We retrieve new information by utilizing magnetic latitude and local time dependence, correlation analyses, and quantification of the departure of smaller from larger scales. We find that (1) FACs characteristics and dependence on controlling parameters do not map between scales in a straight forward manner, (2) relationships between FAC scales exhibit local time dependence, and (3) the dayside high-latitude region is characterized by remarkably distinct FAC behavior when analyzed at different scales, and the locations of distinction correspond to "anomalous" ionosphere-thermosphere behavior. Comparing with nominal large-scale FACs, we find that differences are characterized by a horseshoe shape, maximizing across dayside local times, and that difference magnitudes increase when smaller-scale observed FACs are considered. We suggest that both new physics and increased resolution of models are required to address the multiscale complexities. We include a summary table of our findings to provide a quick reference for differences between multiscale FACs.

Advancing intercultural competency: Canadian engineering employers' experiences with immigrant engineers

NASA Astrophysics Data System (ADS)

Friesen, Marcia; Ingram, Sandra

2013-05-01

This paper explores Canadian engineering employers' perceptions of and experiences with internationally educated engineers (recent immigrants to Canada) employed in their organisations for varying lengths of time. Qualitative data were collected from employers using focus group methodology. Findings reflected employers' observations of culturally different behaviours and characteristics in their internationally educated employees, employers' reactions to cultural differences ranging from negative attributions to tolerance, and the implementation of largely ad hoc intra-organisational strategies for managing cultural differences in employer-employee relationships. Findings exposed the lack of corporate intercultural competency in the Canadian engineering profession. Equity and gatekeeping implications are discussed.

Association between findings on palmarodorsal radiographic images and detection of a fracture in the proximal sesamoid bones of forelimbs obtained from cadavers of racing Thoroughbreds.

PubMed

Anthenill, Lucy A; Stover, Susan M; Gardner, Ian A; Hill, Ashley E; Lee, Christina M; Anderson, Mark L; Barr, Bradd C; Read, Deryck H; Johnson, Bill J; Woods, Leslie W; Daft, Barbara M; Kinde, Hailu; Moore, Janet D; Farman, Cynthia A; Odani, Jenee S; Pesavento, Patricia A; Uzal, Francisco A; Case, James T; Ardans, Alex A

2006-05-01

To determine the distribution for limbs and bones in horses with fractures of the proximal sesamoid bones and relationships with findings on palmarodorsal radiographic images. Proximal sesamoid bones obtained from both forelimbs of cadavers of 328 racing Thoroughbreds. Osteophytes; large vascular channels; and fracture location, orientation, configuration, and margin distinctness were categorized by use of high-detail contact palmarodorsal radiographs. Distributions of findings were determined. Relationships between radiographic findings and fracture characteristics were examined by use of chi2 and logistic regression techniques. Fractures were detected in 136 (41.5%) horses. Biaxial fractures were evident in 109 (80%) horses with a fracture. Osteophytes and large vascular channels were evident in 266 (81%) and 325 (99%) horses, respectively. Medial bones typically had complete transverse or split transverse simple fractures, indistinct fracture margins, > 1 vascular channel that was > 1 mm in width, and osteophytes in abaxial wing and basilar middle or basilar abaxial locations. Lateral bones typically had an oblique fracture and distinct fracture margins. Odds of proximal sesamoid bone fracture were approximately 2 to 5 times higher in bones without radiographic evidence of osteophytes or large vascular channels, respectively. Biaxial fractures of proximal sesamoid bones were common in cadavers of racing Thoroughbreds. Differences between medial and lateral bones for characteristics associated with fracture may relate to differences in fracture pathogeneses for these bones. Osteophytes and vascular channels were common findings; however, fractures were less likely to occur in bones with these features.

Large-scale tropospheric transport in the Chemistry-Climate Model Initiative (CCMI) simulations

NASA Astrophysics Data System (ADS)

Orbe, Clara; Yang, Huang; Waugh, Darryn W.; Zeng, Guang; Morgenstern, Olaf; Kinnison, Douglas E.; Lamarque, Jean-Francois; Tilmes, Simone; Plummer, David A.; Scinocca, John F.; Josse, Beatrice; Marecal, Virginie; Jöckel, Patrick; Oman, Luke D.; Strahan, Susan E.; Deushi, Makoto; Tanaka, Taichu Y.; Yoshida, Kohei; Akiyoshi, Hideharu; Yamashita, Yousuke; Stenke, Andreas; Revell, Laura; Sukhodolov, Timofei; Rozanov, Eugene; Pitari, Giovanni; Visioni, Daniele; Stone, Kane A.; Schofield, Robyn; Banerjee, Antara

2018-05-01

Understanding and modeling the large-scale transport of trace gases and aerosols is important for interpreting past (and projecting future) changes in atmospheric composition. Here we show that there are large differences in the global-scale atmospheric transport properties among the models participating in the IGAC SPARC Chemistry-Climate Model Initiative (CCMI). Specifically, we find up to 40 % differences in the transport timescales connecting the Northern Hemisphere (NH) midlatitude surface to the Arctic and to Southern Hemisphere high latitudes, where the mean age ranges between 1.7 and 2.6 years. We show that these differences are related to large differences in vertical transport among the simulations, in particular to differences in parameterized convection over the oceans. While stronger convection over NH midlatitudes is associated with slower transport to the Arctic, stronger convection in the tropics and subtropics is associated with faster interhemispheric transport. We also show that the differences among simulations constrained with fields derived from the same reanalysis products are as large as (and in some cases larger than) the differences among free-running simulations, most likely due to larger differences in parameterized convection. Our results indicate that care must be taken when using simulations constrained with analyzed winds to interpret the influence of meteorology on tropospheric composition.

Simulation of coherent nonlinear neutrino flavor transformation in the supernova environment: Correlated neutrino trajectories

NASA Astrophysics Data System (ADS)

Duan, Huaiyu; Fuller, George M.; Carlson, J.; Qian, Yong-Zhong

2006-11-01

We present results of large-scale numerical simulations of the evolution of neutrino and antineutrino flavors in the region above the late-time post-supernova-explosion proto-neutron star. Our calculations are the first to allow explicit flavor evolution histories on different neutrino trajectories and to self-consistently couple flavor development on these trajectories through forward scattering-induced quantum coupling. Employing the atmospheric-scale neutrino mass-squared difference (|δm2|≃3×10-3eV2) and values of θ13 allowed by current bounds, we find transformation of neutrino and antineutrino flavors over broad ranges of energy and luminosity in roughly the “bi-polar” collective mode. We find that this large-scale flavor conversion, largely driven by the flavor off-diagonal neutrino-neutrino forward scattering potential, sets in much closer to the proto-neutron star than simple estimates based on flavor-diagonal potentials and Mikheyev-Smirnov-Wolfenstein evolution would indicate. In turn, this suggests that models of r-process nucleosynthesis sited in the neutrino-driven wind could be affected substantially by active-active neutrino flavor mixing, even with the small measured neutrino mass-squared differences.

Sex and gender differences in pain and analgesia.

PubMed

Mogil, Jeffrey S; Bailey, Andrea L

2010-01-01

It is a clinical reality that women make up the large majority of chronic pain patients, and there is now consensus from laboratory experiments that when differences are seen, women are more sensitive to pain than men. Research in this field has now begun to concentrate on finding explanations for this sex difference. Although sex differences in sociocultural, psychological, and experiential factors likely play important roles, evidence largely from animal studies has revealed surprisingly robust and often qualitative sex differences at low levels of the neuraxis. Although not yet able to affect clinical practice, the continued study of sex differences in pain may have important implications for the development of new analgesic strategies. Copyright © 2010 Elsevier B.V. All rights reserved.

On Matrix Sampling and Imputation of Context Questionnaires with Implications for the Generation of Plausible Values in Large-Scale Assessments

ERIC Educational Resources Information Center

Kaplan, David; Su, Dan

2016-01-01

This article presents findings on the consequences of matrix sampling of context questionnaires for the generation of plausible values in large-scale assessments. Three studies are conducted. Study 1 uses data from PISA 2012 to examine several different forms of missing data imputation within the chained equations framework: predictive mean…

Race and Stratification in College Enrollment over Time. CEPA Working Paper No. 16-14

ERIC Educational Resources Information Center

Baker, Rachel; Klasik, Daniel; Reardon, Sean F.

2016-01-01

In this study we examine trends in segregation by race and ethnicity in higher education from 1985 to 2013. We have three key findings. Over the past 30 years, students from different groups have attended college at increasingly similar rates; gaps are decreasing. But these decreases have been driven largely by large increases in minority student…

Replica Exchange with Solute Tempering: Efficiency in Large Scale Systems

PubMed Central

Huang, Xuhui; Hagen, Morten; Kim, Byungchan; Friesner, Richard A.; Zhou, Ruhong; Berne, B. J.

2009-01-01

We apply the recently developed replica exchange with solute tempering (REST) to three large solvated peptide systems: an α-helix, a β-hairpin, and a TrpCage, with these peptides defined as the “central group”. We find that our original implementation of REST is not always more efficient than the replica exchange method (REM). Specifically, we find that exchanges between folded (F) and unfolded (U) conformations with vastly different structural energies are greatly reduced by the nonappearance of the water self-interaction energy in the replica exchange acceptance probabilities. REST, however, is expected to remain useful for a large class of systems for which the energy gap between the two states is not large, such as weakly bound protein–ligand complexes. Alternatively, a shell of water molecules can be incorporated into the central group, as discussed in the original paper. PMID:17439169

Getting Back to the Main Point: A Reply to Miller et al.

ERIC Educational Resources Information Center

Harrison, Allyson G.; Holmes, Alana; Silvestri, Robert; Armstrong, Irene T.

2015-01-01

Miller et al. have challenged the findings of our two previous studies, based largely on the assumption that our findings are biased due to the clinical sample used. However, they fail to address the primary tenet of our studies, namely, that clinicians will obtain different scores on the Wechsler Adult Intelligence Scale-IV (WAIS-IV) depending on…

Gender disparities in second-semester college physics: The incremental effects of a ``smog of bias''

NASA Astrophysics Data System (ADS)

Kost-Smith, Lauren E.; Pollock, Steven J.; Finkelstein, Noah D.

2010-07-01

Our previous research [Kost , Phys. Rev. ST Phys. Educ. Res. 5, 010101 (2009)10.1103/PhysRevSTPER.5.010101] examined gender differences in the first-semester, introductory physics class at the University of Colorado at Boulder. We found that: (1) there were gender differences in several aspects of the course, including conceptual survey performance, (2) these differences persisted despite the use of interactive engagement techniques, and (3) the post-test gender differences could largely be attributed to differences in males’ and females’ prior physics and math performance and their incoming attitudes and beliefs. In the current study, we continue to characterize gender differences in our physics courses by examining the second-semester, electricity and magnetism course. We analyze three factors: student retention from Physics 1 to Physics 2, student performance, and students’ attitudes and beliefs about physics, and find gender differences in all three of these areas. Specifically, females are less likely to stay in the physics major than males. Despite males and females performing about equally on the conceptual pretest, we find that females score about 6 percentage points lower than males on the conceptual post-test. In most semesters, females outperform males on homework and participation, and males outperform females on exams, resulting in course grades of males and females that are not significantly different. In terms of students’ attitudes and beliefs, we find that both males and females shift toward less expertlike beliefs over the course of Physics 2. Shifts are statistically equal for all categories except for the Personal Interest category, where females have more negative shifts than males. A large fraction of the conceptual post-test gender gap (up to 60%) can be accounted for by differences in males’ and females’ prior physics and math performance and their pre-Physics 2 attitudes and beliefs. Taken together, the results of this study suggest that it is an accumulation of small gender differences over time that may be responsible for the large differences that we observe in physics participation of males and females.

On the predictability of individual events in power-law systems

NASA Astrophysics Data System (ADS)

de, Rumi

2006-11-01

We consider a modified Burridge-Knopoff model with a view to understand results of acoustic emission (AE) relevant to earthquakes by adding a dissipative term which mimics bursts of acous- tic signals. Interestingly, we find a precursor effect in the cumulative energy dissipated which allows identification of a large slip event. Further, the AE activity for several large slip events follows a universal stretched exponential behavior with corrections in terms of time-to-failure. We find that many features of the statistics of AE signals such as their amplitudes, durations and the intervals between successive AE bursts obey power laws consistent with recent experimental results. Large magnitude events have different power law from that of the small ones, the latter being sensitive to the pulling speed.

Understanding the Sex Difference in Vulnerability to Adolescent Depression: An Examination of Child and Parent Characteristics

ERIC Educational Resources Information Center

Eberhart, Nicole K.; Shih, Josephine H.; Hammen, Constance L.; Brennan, Patricia A.

2006-01-01

This study examined sex differences in risk factors associated with adolescent depression in a large sample of boys and girls. Moderation and mediation explanatory models of the sex difference in likelihood of depression were examined. Findings indicate that the factors associated with depression in adolescent boys and girls are quite similar. All…

Let's Get This Straightened Out: Finding a Place and Presence for Sexual/Gender Identity-Difference in Peace Education

ERIC Educational Resources Information Center

Mizzi, Robert

2010-01-01

Expressions of homo/transphobia continue to rupture and sometimes even erase the lives of persons with sexual/gender identity-difference across the globe. Despite this, experiences with violence of this nature largely go unexamined in peace education scholarship. In order to begin a discussion about sexuality/gender identity-difference within a…

School Context and Gender Differences in Mathematical Performance among School Graduates in Russia

ERIC Educational Resources Information Center

Bessudnov, Alexey; Makarov, Alexey

2015-01-01

Gender differences in mathematical performance have received considerable scrutiny in the fields of sociology, economics and psychology. We analyse a large data-set of high school graduates who took a standardised mathematical test in Russia in 2011 (n = 738,456) and find no substantial difference in mean test scores across boys and girls.…

Visual Word Recognition Across the Adult Lifespan

PubMed Central

Cohen-Shikora, Emily R.; Balota, David A.

2016-01-01

The current study examines visual word recognition in a large sample (N = 148) across the adult lifespan and across a large set of stimuli (N = 1187) in three different lexical processing tasks (pronunciation, lexical decision, and animacy judgments). Although the focus of the present study is on the influence of word frequency, a diverse set of other variables are examined as the system ages and acquires more experience with language. Computational models and conceptual theories of visual word recognition and aging make differing predictions for age-related changes in the system. However, these have been difficult to assess because prior studies have produced inconsistent results, possibly due to sample differences, analytic procedures, and/or task-specific processes. The current study confronts these potential differences by using three different tasks, treating age and word variables as continuous, and exploring the influence of individual differences such as vocabulary, vision, and working memory. The primary finding is remarkable stability in the influence of a diverse set of variables on visual word recognition across the adult age spectrum. This pattern is discussed in reference to previous inconsistent findings in the literature and implications for current models of visual word recognition. PMID:27336629

Cluster galaxy dynamics and the effects of large-scale environment

NASA Astrophysics Data System (ADS)

White, Martin; Cohn, J. D.; Smit, Renske

2010-11-01

Advances in observational capabilities have ushered in a new era of multi-wavelength, multi-physics probes of galaxy clusters and ambitious surveys are compiling large samples of cluster candidates selected in different ways. We use a high-resolution N-body simulation to study how the influence of large-scale structure in and around clusters causes correlated signals in different physical probes and discuss some implications this has for multi-physics probes of clusters (e.g. richness, lensing, Compton distortion and velocity dispersion). We pay particular attention to velocity dispersions, matching galaxies to subhaloes which are explicitly tracked in the simulation. We find that not only do haloes persist as subhaloes when they fall into a larger host, but groups of subhaloes retain their identity for long periods within larger host haloes. The highly anisotropic nature of infall into massive clusters, and their triaxiality, translates into an anisotropic velocity ellipsoid: line-of-sight galaxy velocity dispersions for any individual halo show large variance depending on viewing angle. The orientation of the velocity ellipsoid is correlated with the large-scale structure, and thus velocity outliers correlate with outliers caused by projection in other probes. We quantify this orientation uncertainty and give illustrative examples. Such a large variance suggests that velocity dispersion estimators will work better in an ensemble sense than for any individual cluster, which may inform strategies for obtaining redshifts of cluster members. We similarly find that the ability of substructure indicators to find kinematic substructures is highly viewing angle dependent. While groups of subhaloes which merge with a larger host halo can retain their identity for many Gyr, they are only sporadically picked up by substructure indicators. We discuss the effects of correlated scatter on scaling relations estimated through stacking, both analytically and in the simulations, showing that the strong correlation of measures with mass and the large scatter in mass at fixed observable mitigate line-of-sight projections.

Prospective survey of veterinary practitioners’ primary assessment of equine colic: clinical features, diagnoses, and treatment of 120 cases of large colon impaction

PubMed Central

2014-01-01

Background Large colon impactions are a common cause of colic in the horse. There are no scientific reports on the clinical presentation, diagnostic tests and treatments used in first opinion practice for large colon impaction cases. The aim of this study was to describe the presentation, diagnostic approach and treatment at the primary assessment of horses with large colon impactions. Methods Data were collected prospectively from veterinary practitioners on the primary assessment of equine colic cases over a 12 month period. Inclusion criteria were a diagnosis of primary large colon impaction and positive findings on rectal examination. Data recorded for each case included history, signalment, clinical and diagnostic findings, treatment on primary assessment and final case outcome. Case outcomes were categorised into three groups: simple medical (resolved with single treatment), complicated medical (resolved with multiple medical treatments) and critical (required surgery, were euthanased or died). Univariable analysis using one-way ANOVA and Tukey’s post-hoc test, Kruskal Wallis with Dunn’s post-hoc test and Chi squared analysis were used to compare between different outcome categories. Results 1032 colic cases were submitted by veterinary practitioners: 120 cases met the inclusion criteria for large colon impaction. Fifty three percent of cases were categorised as simple medical, 36.6% as complicated medical, and 9.2% as critical. Most cases (42.1%) occurred during the winter. Fifty nine percent of horses had had a recent change in management, 43% of horses were not ridden, and 12.5% had a recent / current musculoskeletal injury. Mean heart rate was 43bpm (range 26-88) and most cases showed mild signs of pain (67.5%) and reduced gut sounds (76%). Heart rate was significantly increased and gut sounds significantly decreased in critical compared to simple medical cases (p<0.05). Fifty different treatment combinations were used, with NSAIDs (93%) and oral fluids (71%) being administered most often. Conclusions Large colon impactions typically presented with mild signs of colic; heart rate and gut sounds were the most useful parameters to distinguish between simple and critical cases at the primary assessment. The findings of seasonal incidence and associated management factors are consistent with other studies. Veterinary practitioners currently use a wide range of different treatment combinations for large colon impactions. PMID:25238179

Optimal processor assignment for pipeline computations

NASA Technical Reports Server (NTRS)

Nicol, David M.; Simha, Rahul; Choudhury, Alok N.; Narahari, Bhagirath

1991-01-01

The availability of large scale multitasked parallel architectures introduces the following processor assignment problem for pipelined computations. Given a set of tasks and their precedence constraints, along with their experimentally determined individual responses times for different processor sizes, find an assignment of processor to tasks. Two objectives are of interest: minimal response given a throughput requirement, and maximal throughput given a response time requirement. These assignment problems differ considerably from the classical mapping problem in which several tasks share a processor; instead, it is assumed that a large number of processors are to be assigned to a relatively small number of tasks. Efficient assignment algorithms were developed for different classes of task structures. For a p processor system and a series parallel precedence graph with n constituent tasks, an O(np2) algorithm is provided that finds the optimal assignment for the response time optimization problem; it was found that the assignment optimizing the constrained throughput in O(np2log p) time. Special cases of linear, independent, and tree graphs are also considered.

Social Relationships and Motivation in Secondary School: Four Different Motivation Types

ERIC Educational Resources Information Center

Raufelder, Diana; Jagenow, Danilo; Drury, Kate; Hoferichter, Frances

2013-01-01

In order to enhance our understanding of individual differences in scholastic motivation, the present study examined if social relationships in school are equally important for motivation across a large sample of adolescent students. Based on past research as well as our preliminary findings, it was hypothesized that there would be four different…

Repetition Blindness for Rotated Objects

ERIC Educational Resources Information Center

Hayward, William G.; Zhou, Guomei; Man, Wai-Fung; Harris, Irina M.

2010-01-01

Repetition blindness (RB) is the finding that observers often miss the repetition of an item within a rapid stream of words or objects. Recent studies have shown that RB for objects is largely unaffected by variations in viewpoint between the repeated items. In 5 experiments, we tested RB under different axes of rotation, with different types of…

Dissociating object-based from egocentric transformations in mental body rotation: effect of stimuli size.

PubMed

Habacha, Hamdi; Moreau, David; Jarraya, Mohamed; Lejeune-Poutrain, Laure; Molinaro, Corinne

2018-01-01

The effect of stimuli size on the mental rotation of abstract objects has been extensively investigated, yet its effect on the mental rotation of bodily stimuli remains largely unexplored. Depending on the experimental design, mentally rotating bodily stimuli can elicit object-based transformations, relying mainly on visual processes, or egocentric transformations, which typically involve embodied motor processes. The present study included two mental body rotation tasks requiring either a same-different or a laterality judgment, designed to elicit object-based or egocentric transformations, respectively. Our findings revealed shorter response times for large-sized stimuli than for small-sized stimuli only for greater angular disparities, suggesting that the more unfamiliar the orientations of the bodily stimuli, the more stimuli size affected mental processing. Importantly, when comparing size transformation times, results revealed different patterns of size transformation times as a function of angular disparity between object-based and egocentric transformations. This indicates that mental size transformation and mental rotation proceed differently depending on the mental rotation strategy used. These findings are discussed with respect to the different spatial manipulations involved during object-based and egocentric transformations.

Inter-individual Variability in Soccer Players of Different Age Groups Playing Different Positions

PubMed Central

Nikolaidis, Pantelis; Ziv, Gal; Lidor, Ronnie; Arnon, Michal

2014-01-01

The purpose of this study was twofold: (a) to profile physical characteristics and motor abilities of three age groups of soccer players – under 14 years, 14–17, and over 17, playing different positions – goalkeepers, defenders, midfielders, and forwards; and (b) to examine the inter-individual variability among the players in each age group in all physical and physiological measurements performed in the study. In addition, anthropometric, power, strength, and flexibility tests were administered. Findings showed large inter-individual variability in all three age groups and in all playing positions. Differences between playing positions were found only in the 14–17 group (body mass) and in the over-17 group (body height, body mass, fat-free mass, and mean power in the Wingate Anaerobic Test). Due to the observed large inter-individual variability, it was concluded that the findings obtained in the physical and physiological tests should be interpreted with caution when attempting to differentiate between successful and unsuccessful soccer players, as well as when trying to predict future success in soccer. PMID:25031689

Got power? A systematic review of sample size adequacy in health professions education research.

PubMed

Cook, David A; Hatala, Rose

2015-03-01

Many education research studies employ small samples, which in turn lowers statistical power. We re-analyzed the results of a meta-analysis of simulation-based education to determine study power across a range of effect sizes, and the smallest effect that could be plausibly excluded. We systematically searched multiple databases through May 2011, and included all studies evaluating simulation-based education for health professionals in comparison with no intervention or another simulation intervention. Reviewers working in duplicate abstracted information to calculate standardized mean differences (SMD's). We included 897 original research studies. Among the 627 no-intervention-comparison studies the median sample size was 25. Only two studies (0.3%) had ≥80% power to detect a small difference (SMD > 0.2 standard deviations) and 136 (22%) had power to detect a large difference (SMD > 0.8). 110 no-intervention-comparison studies failed to find a statistically significant difference, but none excluded a small difference and only 47 (43%) excluded a large difference. Among 297 studies comparing alternate simulation approaches the median sample size was 30. Only one study (0.3%) had ≥80% power to detect a small difference and 79 (27%) had power to detect a large difference. Of the 128 studies that did not detect a statistically significant effect, 4 (3%) excluded a small difference and 91 (71%) excluded a large difference. In conclusion, most education research studies are powered only to detect effects of large magnitude. For most studies that do not reach statistical significance, the possibility of large and important differences still exists.

How International Large-Scale Skills Assessments Engage with National Actors: Mobilising Networks through Policy, Media and Public Knowledge

ERIC Educational Resources Information Center

Hamilton, Mary

2017-01-01

This paper examines how international, large-scale skills assessments (ILSAs) engage with the broader societies they seek to serve and improve. It looks particularly at the discursive work that is done by different interest groups and the media through which the findings become part of public conversations and are translated into usable form in…

Large-scale particle acceleration by magnetic reconnection during solar flares

NASA Astrophysics Data System (ADS)

Li, X.; Guo, F.; Li, H.; Li, G.; Li, S.

2017-12-01

Magnetic reconnection that triggers explosive magnetic energy release has been widely invoked to explain the large-scale particle acceleration during solar flares. While great efforts have been spent in studying the acceleration mechanism in small-scale kinetic simulations, there have been rare studies that make predictions to acceleration in the large scale comparable to the flare reconnection region. Here we present a new arrangement to study this problem. We solve the large-scale energetic-particle transport equation in the fluid velocity and magnetic fields from high-Lundquist-number MHD simulations of reconnection layers. This approach is based on examining the dominant acceleration mechanism and pitch-angle scattering in kinetic simulations. Due to the fluid compression in reconnection outflows and merging magnetic islands, particles are accelerated to high energies and develop power-law energy distributions. We find that the acceleration efficiency and power-law index depend critically on upstream plasma beta and the magnitude of guide field (the magnetic field component perpendicular to the reconnecting component) as they influence the compressibility of the reconnection layer. We also find that the accelerated high-energy particles are mostly concentrated in large magnetic islands, making the islands a source of energetic particles and high-energy emissions. These findings may provide explanations for acceleration process in large-scale magnetic reconnection during solar flares and the temporal and spatial emission properties observed in different flare events.

Confinement of anomalous liquids in nanoporous matrices.

PubMed

Strekalova, Elena G; Luo, Jiayuan; Stanley, H Eugene; Franzese, Giancarlo; Buldyrev, Sergey V

2012-09-07

Using molecular dynamics simulations, we investigate the effects of different nanoconfinements on complex liquids-e.g., colloids or protein solutions-with density anomalies and a liquid-liquid phase transition (LLPT). In all the confinements, we find a strong depletion effect with a large increase in liquid density near the confining surface. If the nanoconfinement is modeled by an ordered matrix of nanoparticles, we find that the anomalies are preserved. On the contrary, if the confinement is modeled by a disordered matrix of nanoparticles, we find a drastically different phase diagram: the LLPT shifts to lower pressures and temperatures, and the anomalies become weaker, as the disorder increases. We find that the density heterogeneities induced by the disordered matrix are responsible for the weakening of the LLPT and the disappearance of the anomalies.

Dynamical Origin and Terrestrial Impact Flux of Large Near-Earth Asteroids

NASA Astrophysics Data System (ADS)

Nesvorný, David; Roig, Fernando

2018-01-01

Dynamical models of the asteroid delivery from the main belt suggest that the current impact flux of diameter D> 10 km asteroids on the Earth is ≃0.5–1 Gyr‑1. Studies of the Near-Earth Asteroid (NEA) population find a much higher flux, with ≃ 7 D> 10 km asteroid impacts per Gyr. Here we show that this problem is rooted in the application of impact probability of small NEAs (≃1.5 Gyr‑1 per object), whose population is well characterized, to large NEAs. In reality, large NEAs evolve from the main belt by different escape routes, have a different orbital distribution, and lower impact probabilities (0.8 ± 0.3 Gyr‑1 per object) than small NEAs. In addition, we find that the current population of two D> 10 km NEAs (Ganymed and Eros) is a slight fluctuation over the long-term average of 1.1+/- 0.5 D> 10 km NEAs in a steady state. These results have important implications for our understanding of the occurrence of the K/T-scale impacts on the terrestrial worlds.

Large herbivores maintain termite-caused differences in herbaceous species diversity patterns.

PubMed

Okullo, Paul; Moe, Stein R

2012-09-01

Termites and large herbivores affect African savanna plant communities. Both functional groups are also important for nutrient redistribution across the landscape. We conducted an experiment to study how termites and large herbivores, alone and in combination, affect herbaceous species diversity patterns in an African savanna. Herbaceous vegetation on large vegetated Macrotermes mounds (with and without large herbivores) and on adjacent savanna areas (with and without large herbivores) was monitored over three years in Lake Mburo National Park, Uganda. We found substantial differences in species richness, alpha diversity, evenness, and stability between termite mound herbaceous vegetation and adjacent savanna vegetation. Within months of fencing, levels of species richness, evenness, and stability were no longer significantly different between savanna and mounds. However, fencing reduced the cumulative number of species, particularly for forbs, of which 48% of the species were lost. Fencing increased the beta diversity (dissimilarity among plots) on the resource-poor (in terms of both nutrients and soil moisture) savanna areas, while it did not significantly affect beta diversity on the resource-rich termite mounds. While termites cause substantial heterogeneity in savanna vegetation, large herbivores further amplify these differences by reducing beta diversity on the savanna areas. Large herbivores are, however, responsible for the maintenance of a large number of forbs at the landscape level. These findings suggest that the mechanisms underlying the effects of termites and large herbivores on savanna plant communities scale up to shape community structure and dynamics at a landscape level.

Where glaciers meet water: Subaqueous melt and its relevance to glaciers in various settings

NASA Astrophysics Data System (ADS)

Truffer, Martin; Motyka, Roman J.

2016-03-01

Glacier change is ubiquitous, but the fastest and largest magnitude changes occur in glaciers that terminate in water. This includes the most rapidly retreating glaciers, and also several advancing ones, often in similar regional climate settings. Furthermore, water-terminating glaciers show a large range in morphology, particularly when ice flow into ocean water is compared to that into freshwater lakes. All water-terminating glaciers share the ability to lose significant volume of ice at the front, either through mechanical calving or direct melt from the water in contact. Here we present a review of the subaqueous melt process. We discuss the relevant physics and show how different physical settings can lead to different glacial responses. We find that subaqueous melt can be an important trigger for glacier change. It can explain many of the morphological differences, such as the existence or absence of floating tongues. Subaqueous melting is influenced by glacial runoff, which is largely a function of atmospheric conditions. This shows a tight connection between atmosphere, oceans and lakes, and glaciers. Subaqueous melt rates, even if shown to be large, should always be discussed in the context of ice supply to the glacier front to assess its overall relevance. We find that melt is often relevant to explain seasonal evolution, can be instrumental in shifting a glacier into a different dynamical regime, and often forms a large part of a glacier's mass loss. On the other hand, in some cases, melt is a small component of mass loss and does not significantly affect glacier response.

N-body simulations of gravitational redshifts and other relativistic distortions of galaxy clustering

NASA Astrophysics Data System (ADS)

Zhu, Hongyu; Alam, Shadab; Croft, Rupert A. C.; Ho, Shirley; Giusarma, Elena

2017-10-01

Large redshift surveys of galaxies and clusters are providing the first opportunities to search for distortions in the observed pattern of large-scale structure due to such effects as gravitational redshift. We focus on non-linear scales and apply a quasi-Newtonian approach using N-body simulations to predict the small asymmetries in the cross-correlation function of two galaxy different populations. Following recent work by Bonvin et al., Zhao and Peacock and Kaiser on galaxy clusters, we include effects which enter at the same order as gravitational redshift: the transverse Doppler effect, light-cone effects, relativistic beaming, luminosity distance perturbation and wide-angle effects. We find that all these effects cause asymmetries in the cross-correlation functions. Quantifying these asymmetries, we find that the total effect is dominated by the gravitational redshift and luminosity distance perturbation at small and large scales, respectively. By adding additional subresolution modelling of galaxy structure to the large-scale structure information, we find that the signal is significantly increased, indicating that structure on the smallest scales is important and should be included. We report on comparison of our simulation results with measurements from the SDSS/BOSS galaxy redshift survey in a companion paper.

Fleshy fruit characteristics in a temperate deciduous forest of Japan: how unique are they?

PubMed

Masaki, Takashi; Takahashi, Kazuaki; Sawa, Ayako; Kado, Tomoyuki; Naoe, Shoji; Koike, Shinsuke; Shibata, Mitsue

2012-01-01

This study investigated the fleshy fruit characteristics of 28 woody species in a Japanese temperate forest where large sedentary seed-dispersing mammals are present. We tested whether the findings in previous studies in temperate forests of Europe and North America are universal or not. Results have suggested that fruits of all species were eaten both by birds and mammals except for four species with larger fruits, which were eaten only by mammals. A gradient was found from a syndrome characterized by small, oily, and large-seeded fruits to a syndrome characterized by large, succulent, non-oily, and small-seeded fruits. The sizes and colors of the fruits were not conspicuously different from previous findings in Europe and North America. On the other hand, nitrogen and lipids in the fleshy part did not show seasonally increasing trends, or even seasonally decreasing trends in terms of dry weight. This result, suggesting the absence of community-level adaptation of fruit traits to migratory bird dispersers, contrasted with findings in Europe and North America. Large sedentary arboreal or tree-climbing mammals may have a greater effect on the evolution of fruit-disperser relations than opportunistic migratory birds.

Rate Analysis of Two Photovoltaic Systems in San Diego

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

Doris, E.; Ong, S.; Van Geet, O.

2009-07-01

Analysts have found increasing evidence that rate structure has impacts on the economics of solar systems. This paper uses 2007 15-minute interval photovoltaic (PV) system and load data from two San Diego City water treatment facilities to illustrate impacts of different rate designs. The comparison is based on rates available in San Diego at the time of data collection and include proportionately small to large demand charges (relative to volumetric consumption), and varying on- and off- peak times. Findings are twofold for these large commercial systems: 1) transferring costs into demand charges does not result in savings and 2) changesmore » in peak times do not result in a major cost difference during the course of a year. While lessons learned and discussion on rate components are based on the findings, the applicability is limited to buildings with similar systems, environments, rate options, and loads.« less

Job Stress in the United Kingdom: Are Small and Medium-Sized Enterprises and Large Enterprises Different?

PubMed

Lai, Yanqing; Saridakis, George; Blackburn, Robert

2015-08-01

This paper examines the relationships between firm size and employees' experience of work stress. We used a matched employer-employee dataset (Workplace Employment Relations Survey 2011) that comprises of 7182 employees from 1210 private organizations in the United Kingdom. Initially, we find that employees in small and medium-sized enterprises experience lower level of overall job stress than those in large enterprises, although the effect disappears when we control for individual and organizational characteristics in the model. We also find that quantitative work overload, job insecurity and poor promotion opportunities, good work relationships and poor communication are strongly associated with job stress in the small and medium-sized enterprises, whereas qualitative work overload, poor job autonomy and employee engagements are more related with larger enterprises. Hence, our estimates show that the association and magnitude of estimated effects differ significantly by enterprise size. Copyright © 2013 John Wiley & Sons, Ltd.

Men, women…who cares? A population-based study on sex differences and gender roles in empathy and moral cognition.

PubMed

Baez, Sandra; Flichtentrei, Daniel; Prats, María; Mastandueno, Ricardo; García, Adolfo M; Cetkovich, Marcelo; Ibáñez, Agustín

2017-01-01

Research on sex differences in empathy has revealed mixed findings. Whereas experimental and neuropsychological measures show no consistent sex effect, self-report data consistently indicates greater empathy in women. However, available results mainly come from separate populations with relatively small samples, which may inflate effect sizes and hinder comparability between both empirical corpora. To elucidate the issue, we conducted two large-scale studies. First, we examined whether sex differences emerge in a large population-based sample (n = 10,802) when empathy is measured with an experimental empathy-for-pain paradigm. Moreover, we investigated the relationship between empathy and moral judgment. In the second study, a subsample (n = 334) completed a self-report empathy questionnaire. Results showed some sex differences in the experimental paradigm, but with minuscule effect sizes. Conversely, women did portray themselves as more empathic through self-reports. In addition, utilitarian responses to moral dilemmas were less frequent in women, although these differences also had small effect sizes. These findings suggest that sex differences in empathy are highly driven by the assessment measure. In particular, self-reports may induce biases leading individuals to assume gender-role stereotypes. Awareness of the role of measurement instruments in this field may hone our understanding of the links between empathy, sex differences, and gender roles.

Differences in delay discounting between smokers and nonsmokers remain when both rewards are delayed

PubMed Central

Mitchell, Suzanne H.; Wilson, Vanessa B.

2013-01-01

Rationale When offered a choice between a small monetary reward available immediately (SmallNow) versus a larger reward available after a delay (LargeLater), smokers select the SmallNow alternative more than nonsmokers. That is, smokers discount the value of the LargeLater reward more than nonsmokers. Objectives To investigate whether this group difference was due to smokers overweighing the value of rewards available immediately compared with nonsmokers, we examined whether the group difference was also seen when both alternatives were delayed, i.e., when choosing between a SmallSoon reward and a LargeLater reward. Methods In Experiment 1, smokers and nonsmokers completed a task including SmallNow versus LargeLater choices and SmallSoon versus LargeLater choices. In Experiment 2, smokers and nonsmokers completed the same task but with hypothetical choices. Results Analyses using hyperbolic and double exponential (β-δ) models replicate prior findings that smokers discount the LargeLater reward more than nonsmokers when the smaller reward is available immediately. The smoker-nonsmoker difference was also seen when the smaller reward was slightly delayed, though this effect was primarily driven by heightened discounting in male smokers. However, for potentially real rewards only, this smoker-nonsmoker difference was significantly reduced when the smaller reward was delayed. Conclusions The smoker-nonsmoker difference in discounting is not confined to situations involving immediate rewards. Differences associated with potentially real vs. hypothetical rewards and gender underscore the complexity of the smoking-delay discounting relationship. PMID:21983917

[Personalized drug therapy-directed clinical pharmacology research based on genetic polymorphisms and pharmacokinetics analysis].

PubMed

Hayashi, Hideki

2013-01-01

In this decade, the field of pharmacogenomics (PGx), which is related to pharmacokinetics (PK) or pharmacodynamics (PD), has attracted much attention because it may provide a possible explanation for individual differences in the clinical efficacy of drugs. For the development of personalized drug therapy, it is important to accumulate evidence from PK/PD/PGx analysis in clinical trials. Warfarin (WF) is one of the most widely prescribed anticoagulants for the prevention and treatment of venous and arterial thromboembolism. However, large interindividual and interethnic differences have been observed in the WF dose required to elicit the anticoagulant effect. We investigated the factors influencing the WF maintenance dose in Japanese patients. Our study confirmed a large interindividual variability in the WF maintenance dose that was due to a VKORC1 1639 G>A polymorphism and differences in body weight, age, and serum albumin. In addition, we found that the CYP4F2 genotype affects the plasma concentration of menaquinone-4, and that this finding was correlated with the WF sensitivity index in Japanese pediatric patients. Methotrexate (MTX) is an antifolate that is widely used to treat rheumatoid arthritis (RA) and cancer. The response to low-dose MTX demonstrated wide interpatient variability; however, the contributing factors remain unclear. We found that the frequency of the RFC1 80A allele was higher in RA patients treated with MTX alone compared with patients who received biological disease-modifying antirheumatic drugs (bDMARDs). This finding may support the combined use of bDMARDs and MTX. Further large-scale prospective clinical trials are required to confirm these findings.

Racial, Ethnic, and Gender Differences in School Discipline among U.S. High School Students: 1991-2005

ERIC Educational Resources Information Center

Wallace, John M., Jr.; Goodkind, Sara; Wallace, Cynthia M.; Bachman, Jerald G.

2008-01-01

Large nationally representative samples of White, Black, Hispanic, Asian American, and American Indian students were used in this study to examine current patterns and recent trends in racial, ethnic, and gender differences in school discipline from 1991 to 2005. Findings revealed that Black, Hispanic, and American Indian youth are slightly more…

An empirical assessment of generational differences in basic human values.

PubMed

Lyons, Sean T; Duxbury, Linda; Higgins, Christopher

2007-10-01

This study assessed generational differences in human values as measured by the Schwartz Value Survey. It was proposed that the two most recent generations, Millennials and Generation Xers, would value Self-enhancement and Openness to Change more than the two older generations, Baby Boomers and Matures, while the two older generations would value Self-transcendence and Conservation more. The hypotheses were tested with a combined sample of Canadian knowledge workers and undergraduate business students (N = 1,194). Two hypotheses were largely supported, although an unexpectedly large difference was observed between Millennials and Generation Xers with respect to Openness to Change and Self-enhancement. The findings suggest that generation is a useful variable in examining differences in social values.

Marital disruption and health insurance.

PubMed

Peters, H Elizabeth; Simon, Kosali; Taber, Jamie Rubenstein

2014-08-01

Despite the high levels of marital disruption in the United States and the fact that a significant portion of health insurance coverage for those less than age 65 is based on family membership, surprisingly little research is available on the consequences of marital disruption for the health insurance coverage of men, women, and children. We address this shortfall by examining patterns of coverage surrounding marital disruption for men, women, and children, further subset by educational level. Using the 1996, 2001, and 2004 panels of the Survey of Income and Program Participation (SIPP), we find large differences in health insurance coverage across marital status groups in the cross-section. In longitudinal analyses that focus on within-person change, we find small overall coverage changes but large changes in type of coverage following marital disruption. Both men and women show increases in private coverage in their own names, but offsetting decreases in dependent coverage tend to be larger. One surprising result is that dependent coverage for children also declines after marital dissolution, even though children are still likely to be eligible for that coverage. Children and (to a lesser extent) women show increases in public coverage around the time of divorce or separation. We also find that these patterns differ by education. The most vulnerable group appears to be lower-educated women with children because the increases in private, own-name, and public insurance are not large enough to offset the large decrease in dependent coverage. As the United States implements federal health reform, it is critical that we understand the ways in which life course events-specifically, marital disruption-shape the dynamic patterns of coverage.

Neuroradiologic Characteristics of Primary Angiitis of the Central Nervous System According to the Affected Vessel Size.

PubMed

Thaler, Christian; Kaufmann-Bühler, Ann-Katrin; Gansukh, Tserenchunt; Gansukh, Amarjargal; Schuster, Simon; Bachmann, Henrike; Thomalla, Götz; Magnus, Tim; Matschke, Jakob; Fiehler, Jens; Siemonsen, Susanne

2017-09-05

Magnetic resonance imaging (MRI) has an important impact in diagnosing primary angiitis of the central nervous system (PACNS). However, neuroradiologic findings may vary immensely, making an easy and definite diagnosis challenging. In this retrospective, single center study, we analyzed neuroradiologic findings of patients with PACNS diagnosed at our hospital between 2009 and 2014. Furthermore, we classified patients according to the affected vessel size and compared imaging characteristics between the subgroups. Thirty-three patients were included (mean age 43 [±15.3] years, 17 females) in this study. Patients with positive angiographic findings were classified as either medium or large vessel PACNS and presented more ischemic lesions (p < 0.001) and vessel wall enhancement (p = 0.017) compared to patients with small vessel PACNS. No significant differences were detected for the distribution of contrast-enhancing lesions (parenchymal or leptomeningeal), hemorrhages, or lesions with mass effect. Twenty-five patients underwent brain biopsy. Patients with medium or large vessel PACNS were less likely to have positive biopsy results. It is essential to differentiate between small and medium/large vessel PACNS since results in MRI, digital subtraction angiography and brain biopsy may differ immensely. Since image quality of MR scanners improves gradually and brain biopsy may often be nonspecific or negative, our results emphasize the importance of MRI/MRA in the diagnosis process of PACNS.

Hospital ownership and financial performance: what explains the different findings in the empirical literature?

PubMed

Shen, Yu-Chu; Eggleston, Karen; Lau, Joseph; Schmid, Christopher H

2007-01-01

This study applies meta-analytic methods to conduct a quantitative review of the empirical literature on hospital ownership since 1990. We examine four financial outcomes across 40 studies: cost, revenue, profit margin, and efficiency. We find that variation in the magnitudes of ownership effects can be explained by a study's research focus and methodology. Studies using empirical methods that control for few confounding factors tend to find larger differences between for-profit and not-for-profit hospitals than studies that control for a wider range of confounding factors. Functional form and sample size also matter. Failure to apply log transformation to highly skewed expenditure data yields misleadingly large estimated differences between for-profits and not-for-profits. Studies with fewer than 200 observations also produce larger point estimates and wide confidence intervals.

Large Interstellar Polarisation Survey. II. UV/optical study of cloud-to-cloud variations of dust in the diffuse ISM

NASA Astrophysics Data System (ADS)

Siebenmorgen, R.; Voshchinnikov, N. V.; Bagnulo, S.; Cox, N. L. J.; Cami, J.; Peest, C.

2018-03-01

It is well known that the dust properties of the diffuse interstellar medium exhibit variations towards different sight-lines on a large scale. We have investigated the variability of the dust characteristics on a small scale, and from cloud-to-cloud. We use low-resolution spectro-polarimetric data obtained in the context of the Large Interstellar Polarisation Survey (LIPS) towards 59 sight-lines in the Southern Hemisphere, and we fit these data using a dust model composed of silicate and carbon particles with sizes from the molecular to the sub-micrometre domain. Large (≥6 nm) silicates of prolate shape account for the observed polarisation. For 32 sight-lines we complement our data set with UVES archive high-resolution spectra, which enable us to establish the presence of single-cloud or multiple-clouds towards individual sight-lines. We find that the majority of these 35 sight-lines intersect two or more clouds, while eight of them are dominated by a single absorbing cloud. We confirm several correlations between extinction and parameters of the Serkowski law with dust parameters, but we also find previously undetected correlations between these parameters that are valid only in single-cloud sight-lines. We find that interstellar polarisation from multiple-clouds is smaller than from single-cloud sight-lines, showing that the presence of a second or more clouds depolarises the incoming radiation. We find large variations of the dust characteristics from cloud-to-cloud. However, when we average a sufficiently large number of clouds in single-cloud or multiple-cloud sight-lines, we always retrieve similar mean dust parameters. The typical dust abundances of the single-cloud cases are [C]/[H] = 92 ppm and [Si]/[H] = 20 ppm.

Large allele frequency differences between human continental groups are more likely to have occurred by drift during range expansions than by selection.

PubMed

Hofer, T; Ray, N; Wegmann, D; Excoffier, L

2009-01-01

Several studies have found strikingly different allele frequencies between continents. This has been mainly interpreted as being due to local adaptation. However, demographic factors can generate similar patterns. Namely, allelic surfing during a population range expansion may increase the frequency of alleles in newly colonised areas. In this study, we examined 772 STRs, 210 diallelic indels, and 2834 SNPs typed in 53 human populations worldwide under the HGDP-CEPH Diversity Panel to determine to which extent allele frequency differs among four regions (Africa, Eurasia, East Asia, and America). We find that large allele frequency differences between continents are surprisingly common, and that Africa and America show the largest number of loci with extreme frequency differences. Moreover, more STR alleles have increased rather than decreased in frequency outside Africa, as expected under allelic surfing. Finally, there is no relationship between the extent of allele frequency differences and proximity to genes, as would be expected under selection. We therefore conclude that most of the observed large allele frequency differences between continents result from demography rather than from positive selection.

Dissecting health care markets: large versus small businesses.

PubMed

Sherwood, P K; Stevens, R E; Warren, W E

1988-01-01

This article reports the results of a mail survey of businesses in Tulsa, Oklahoma (population 377,900 in the city and 745,300 in the surrounding metropolitan area). The purpose of the research was to analyze differences in health care provision and perspectives between large and small businesses. The survey of 3,200 members of the city's chamber of commerce yielded 640 responses. Analysis of the data revealed distinct differences between the two segments of the health care industry. The findings suggest that market opportunities exist for the development of health care delivery system programs aimed at small businesses.

Benefit finding trajectories in cancer patients receiving psychological care: Predictors and relations to depressive and anxiety symptoms.

PubMed

Zhu, Lei; Ranchor, Adelita V; Helgeson, Vicki S; van der Lee, Marije; Garssen, Bert; Stewart, Roy E; Sanderman, Robbert; Schroevers, Maya J

2018-05-01

This study aimed to (1) identify benefit finding trajectories in cancer patients receiving psychological care; (2) examine associations of benefit finding trajectories with levels of and changes in psychological symptoms; and (3) examine whether socio-demographic and medical characteristics distinguished trajectories. Naturalistic longitudinal study design. Participants were 241 cancer patients receiving psychological care at specialized psycho-oncological institutions in the Netherlands. Data were collected before starting psychological care, and three and 9 months thereafter. Latent class growth analysis was performed to identify benefit finding trajectories. Five benefit finding trajectories were identified: 'high level-stable' (8%), 'very low level-small increase' (16%), 'low level-small increase' (39%), 'low level-large increase' (9%), and 'moderate level-stable' (28%). People in distinct benefit finding trajectories reported significant differential courses of depression but not of anxiety symptoms. Compared with the other four trajectories, people in the 'low level-large increase' trajectory reported the largest decreases in depression over time. Perceptions of cancer prognosis distinguished these trajectories, such that people with a favourable prognosis were more likely to belong to the 'high level-stable' trajectory, while people perceiving an uncertain prognosis were more likely to belong to the 'low level-large increase' trajectory of benefit finding. Cancer patients showed distinct benefit finding trajectories during psychological care. A small proportion reporting a large increase in benefit finding were also most likely to show decreases in depressive symptoms over time. These findings suggest a relation between perceiving benefits from cancer experience and improved psychological functioning in cancer patients receiving psychological care. Statement of contribution What is already known on this subject? People vary in course of benefit finding (BF) after trauma, with some experiencing enhanced BF and others decreased BF. Empirical studies have identified subgroups of cancer patients with distinct BF trajectories. What does this study add? This is the first study showing that cancer patients followed different BF trajectories during psychological care. Only a small proportion experienced clinically meaningful increases in BF over time. More attention is needed for cancer patients with decreased BF, as they are at a higher risk of remaining depressed. © 2017 The British Psychological Society.

How Project Managers Really Manage: An Indepth Look at Some Managers of Large, Complex NASA Projects

NASA Technical Reports Server (NTRS)

Mulenburg, Gerald M.; Impaeilla, Cliff (Technical Monitor)

2000-01-01

This paper reports on a research study by the author that examined ten contemporary National Aeronautics and Space Administration (NASA) complex projects. In-depth interviews with the project managers of these projects provided qualitative data about the inner workings of the project and the methodologies used in establishing and managing the projects. The inclusion of a variety of space, aeronautics, and ground based projects from several different NASA research centers helped to reduce potential bias in the findings toward any one type of project, or technical discipline. The findings address the participants and their individual approaches. The discussion includes possible implications for project managers of other large, complex, projects.

Charged black rings at large D

NASA Astrophysics Data System (ADS)

Chen, Bin; Li, Peng-Cheng; Wang, Zi-zhi

2017-04-01

We study the charged slowly rotating black holes in the Einstein-Maxwell theory in the large dimensions ( D). By using the 1 /D expansion in the near regions of the black holes we obtain the effective equations for the charged slowly rotating black holes. The effective equations capture the dynamics of various stationary solutions, including the charged black ring, the charged slowly rotating Myers-Perry black hole and the charged slowly boosted black string. Via different embeddings we construct these stationary solutions explicitly. For the charged black ring at large D, we find that the charge lowers the angular momentum due to the regularity condition on the solution. By performing the perturbation analysis of the effective equations, we obtain the quasinormal modes of the charge perturbation and the gravitational perturbation analytically. Like the neutral case the charged thin black ring suffers from the Gregory-Laflamme-like instability under the non-axisymmetric perturbations, but the charge weakens the instability. Besides, we find that the large D analysis always respects the cosmic censorship.

What Types of Pornography Do People Find Arousing and Do They Cluster? Assessing Types and Categories of Pornography in a Large-Scale Online Sample.

PubMed

Hald, Gert Martin; Štulhofer, Aleksandar

2016-09-01

Previous research on exposure to different types of pornography has primarily relied on analyses of millions of search terms and histories or on user exposure patterns within a given time period rather than the self-reported frequency of consumption. Further, previous research has almost exclusively relied on theoretical or ad hoc overarching categorizations of different types of pornography, when investigating patterns of pornography exposure, rather than latent structure analyses of these exposure patterns. In contrast, using a large sample of 18- to 40-year-old heterosexual and nonheterosexual Croatian men and women, this study investigated the self-reported frequency of using 27 different types of pornography and statistically explored their latent structures. The results showed substantial differences in consumption patterns across gender and sexual orientation. However, latent structure analyses of the 27 different types of pornography assessed suggested that although several categories of consumption were gender and sexual orientation specific, common categories across the different types of pornography could be established. Based on this finding, a five-item scale was proposed to indicate the use of nonmainstream (paraphilic) pornographic content, as this type of pornography has often been targeted in previous research. To the best of our knowledge, no similar measurement tool has been proposed before.

Sex-role identification and violent victimization: gender differences in the role of masculinity.

PubMed

Daigle, Leah E; Mummert, Sadie J

2014-01-01

Although sex-role identification has been found to be associated with crime and delinquency, the link between sex-role identification and violent victimization has remained largely unexplored. Using the Add Health data, this study examines sex-role identification and its relationship to violent victimization. The findings suggest that masculinity increases the risk of violent victimization for males, but does not for females. Other differences in risk factors across gender were also found. These findings indicate that masculinity is an important construct in understanding the complexity of why some persons are violently victimized and others are not.

Assessing selective sustained attention in 3- to 5-year-old children: Evidence from a new paradigm

PubMed Central

Fisher, Anna; Thiessen, Erik; Godwin, Karrie; Kloos, Heidi; Dickerson, John

2012-01-01

Selective sustained attention (SSA) is crucial for higher-order cognition. Factors promoting SSA are described as exogenous or endogenous. However, there is little research specifying how these factors interact during development – due, largely, to the paucity of developmentally-appropriate paradigms. We report findings from a novel paradigm designed to investigate SSA in preschoolers. The findings indicate that this task (1) has good psychometric and parametric properties, and (2) allows investigation of exogenous and endogenous factors within the same task, making it possible to attribute changes in performance to different mechanisms of attentional control rather than to differences in engagement in different tasks. PMID:23022318

A study to determine the difference in clinical judgment abilities between BSN and non-BSN graduates.

PubMed

Sanford, M; Genrich, S; Nowotny, M

1992-02-01

The purpose of this retrospective study is to determine the difference in clinical judgment abilities of recent baccalaureate nurses (BSN) seeking employment in a large metropolitan hospital and of nurses without a baccalaureate degree. Using an ex post facto design, the orientation records of 116 newly hired nurses were analyzed to determine the clinical judgment abilities using video vignettes produced by Medcom, Inc. Findings indicated that there was no difference in clinical judgment in newly hired BSN and non-BSN graduates. These findings indicate a need for more research studies to determine how clinical judgment is developed and to evaluate teaching strategies that facilitate clinical judgment.

Assessing selective sustained attention in 3- to 5-year-old children: evidence from a new paradigm.

PubMed

Fisher, Anna; Thiessen, Erik; Godwin, Karrie; Kloos, Heidi; Dickerson, John

2013-02-01

Selective sustained attention (SSA) is crucial for higher order cognition. Factors promoting SSA are described as exogenous or endogenous. However, there is little research specifying how these factors interact during development, due largely to the paucity of developmentally appropriate paradigms. We report findings from a novel paradigm designed to investigate SSA in preschoolers. The findings indicate that this task (a) has good psychometric and parametric properties and (b) allows investigation of exogenous and endogenous factors within the same task, making it possible to attribute changes in performance to different mechanisms of attentional control rather than to differences in engagement in different tasks. Copyright © 2012 Elsevier Inc. All rights reserved.

Understanding the Gender Gap in Introductory Physics

NASA Astrophysics Data System (ADS)

Finkelstein, Noah; Kost, Lauren; Pollock, Steven

2008-04-01

While it has been suggested interactive engagement (IE) techniques can eliminate the gender gap (the difference in performance between men and women on measures of conceptual learning), we find that, at our institution, the gender gap persisted from pre to posttest in IE classes (Pollock, Physical Review: ST PER. 3, 010107, 2007). This talk reports on a three-part follow-up study that investigates what factors contribute to the gender gap. First, we analyze student grades in different components of the course and find that men and women's course grades are not significantly different (p>0.1), but men outscore women on exams and women outscore men on homework and participation. Second, we compare average posttest scores of men and women who score similarly on the pretest and find that there are no significant differences between men and women's average posttest scores. Finally, we analyze other factors in addition to the pretest score that could influence the posttest score and find that gender does not account for a majorportion of the variation in posttest scores when a measure of mathematics performance is included. These findings indicate that the gender gap exists in interactive physics classes, but may be due in large part to differences in preparation, background, and math skills as assessed by traditional survey instruments.

On the Rate of Relaxation for the Landau Kinetic Equation and Related Models

NASA Astrophysics Data System (ADS)

Bobylev, Alexander; Gamba, Irene M.; Zhang, Chenglong

2017-08-01

We study the rate of relaxation to equilibrium for Landau kinetic equation and some related models by considering the relatively simple case of radial solutions of the linear Landau-type equations. The well-known difficulty is that the evolution operator has no spectral gap, i.e. its spectrum is not separated from zero. Hence we do not expect purely exponential relaxation for large values of time t>0. One of the main goals of our work is to numerically identify the large time asymptotics for the relaxation to equilibrium. We recall the work of Strain and Guo (Arch Rat Mech Anal 187:287-339 2008, Commun Partial Differ Equ 31:17-429 2006), who rigorously show that the expected law of relaxation is \\exp (-ct^{2/3}) with some c > 0. In this manuscript, we find an heuristic way, performed by asymptotic methods, that finds this "law of two thirds", and then study this question numerically. More specifically, the linear Landau equation is approximated by a set of ODEs based on expansions in generalized Laguerre polynomials. We analyze the corresponding quadratic form and the solution of these ODEs in detail. It is shown that the solution has two different asymptotic stages for large values of time t and maximal order of polynomials N: the first one focus on intermediate asymptotics which agrees with the "law of two thirds" for moderately large values of time t and then the second one on absolute, purely exponential asymptotics for very large t, as expected for linear ODEs. We believe that appearance of intermediate asymptotics in finite dimensional approximations must be a generic behavior for different classes of equations in functional spaces (some PDEs, Boltzmann equations for soft potentials, etc.) and that our methods can be applied to related problems.

Uneven adaptive capacity among fishers in a sea of change

PubMed Central

Fuller, Emma; Crona, Beatrice I.

2017-01-01

Fishers worldwide operate in an environment of uncertainty and constant change. Their ability to manage risk associated with such uncertainty and subsequently adapt to change is largely a function of individual circumstances, including their access to different fisheries. However, explicit attention to the heterogeneity of fishers’ connections to fisheries at the level of the individual has been largely ignored. We illustrate the ubiquitous nature of these connections by constructing a typology of commercial fishers in the state of Maine based on the different fisheries that fishers rely on to sustain their livelihoods and find that there are over 600 combinations. We evaluate the adaptive potential of each strategy, using a set of attributes identified by fisheries experts in the state, and find that only 12% of fishers can be classified as being well positioned to adapt in the face of changing socioeconomic and ecological conditions. Sensitivity to the uneven and heterogeneous capacity of fishers to manage risk and adapt to change is critical to devising effective management strategies that broadly support fishers. This will require greater attention to the social-ecological connectivity of fishers across different jurisdictions. PMID:28604775

Understanding Individual Differences in Language Development across the School Years. Language and Speech Disorders

ERIC Educational Resources Information Center

Tomblin, J. Bruce, Ed.; Nippold, Marilyn A., Ed.

2014-01-01

This volume presents the findings of a large-scale study of individual differences in spoken (and heard) language development during the school years. The goal of the study was to investigate the degree to which language abilities at school entry were stable over time and influential in the child's overall success in important aspects of…

Studies of the limit order book around large price changes

NASA Astrophysics Data System (ADS)

Tóth, B.; Kertész, J.; Farmer, J. D.

2009-10-01

We study the dynamics of the limit order book of liquid stocks after experiencing large intra-day price changes. In the data we find large variations in several microscopical measures, e.g., the volatility the bid-ask spread, the bid-ask imbalance, the number of queuing limit orders, the activity (number and volume) of limit orders placed and canceled, etc. The relaxation of the quantities is generally very slow that can be described by a power law of exponent ≈ 0.4. We introduce a numerical model in order to understand the empirical results better. We find that with a zero intelligence deposition model of the order flow the empirical results can be reproduced qualitatively. This suggests that the slow relaxations might not be results of agents' strategic behaviour. Studying the difference between the exponents found empirically and numerically helps us to better identify the role of strategic behaviour in the phenomena. in here

Unexplained Discontinuity in the US Radiosonde Temperature Data. Part 2; Stratosphere

NASA Technical Reports Server (NTRS)

Redder, Christopher R.; Luers, Jim K.; Eskridge, Robert E.

2003-01-01

In part I of this paper, the United States (US) radiosonde temperature data are shown to have significant and unexplained inhomogeneities in the mid-troposphere. This part discusses the differences between observations taken at 0 and 12 UTC especially in the stratosphere by the Vaisala RS80 radiosondes that are integrated within the National Weather Service's (NWS) Micro-ART system. The results show that there is a large maxima in the horizontal distribution of the monthly means of the 0/12 UTC differences over the central US that is absent over Canada and this maxima is as large as 5 C at 10 hPa. The vertical profiles of the root-mean-square of the monthly means are much larger in the US than those else where. The data clearly shows that the 0/12 UTC differences are largely artificial especially over the central US and originate in the post processing software at observing stations, thus confirming the findings in part I. Special flight data from the NWS's test facility at Sterling, Va. have been obtained. This data can be used to deduce the bias correction applied by Vaisala's post processing system. By analyzing the correction data, it can be shown that the inconsistencies with non-US Vaisala RS80 data as well as most of the large 0/12 UTC differences over the US can be accounted for by multiplying the reported elapsed time (i.e. time since launch) by the factor which is incorrectly applied by the post processing software. After being presented with the findings in this paper, Vaisala further isolated the source of the inconsistencies to a software coding error in the radiation bias correction scheme. The error effects only the software installed at US stations.

Large-Scale functional network overlap is a general property of brain functional organization: Reconciling inconsistent fMRI findings from general-linear-model-based analyses

PubMed Central

Xu, Jiansong; Potenza, Marc N.; Calhoun, Vince D.; Zhang, Rubin; Yip, Sarah W.; Wall, John T.; Pearlson, Godfrey D.; Worhunsky, Patrick D.; Garrison, Kathleen A.; Moran, Joseph M.

2016-01-01

Functional magnetic resonance imaging (fMRI) studies regularly use univariate general-linear-model-based analyses (GLM). Their findings are often inconsistent across different studies, perhaps because of several fundamental brain properties including functional heterogeneity, balanced excitation and inhibition (E/I), and sparseness of neuronal activities. These properties stipulate heterogeneous neuronal activities in the same voxels and likely limit the sensitivity and specificity of GLM. This paper selectively reviews findings of histological and electrophysiological studies and fMRI spatial independent component analysis (sICA) and reports new findings by applying sICA to two existing datasets. The extant and new findings consistently demonstrate several novel features of brain functional organization not revealed by GLM. They include overlap of large-scale functional networks (FNs) and their concurrent opposite modulations, and no significant modulations in activity of most FNs across the whole brain during any task conditions. These novel features of brain functional organization are highly consistent with the brain’s properties of functional heterogeneity, balanced E/I, and sparseness of neuronal activity, and may help reconcile inconsistent GLM findings. PMID:27592153

Investigating the Source of the Gender Gap in Introductory Physics

NASA Astrophysics Data System (ADS)

Kost, Lauren E.; Pollock, Steven J.; Finkelstein, Noah D.

2007-11-01

Our previous research showed that despite the use of interactive engagement (IE) techniques at our institution, the difference in performance between men and women on a conceptual learning survey persisted from pre to posttest. This paper reports on a three-part follow-up study that investigates what factors contribute to the gender gap. First, we analyze student grades in different components of the course and find that men and women's course grades are not significantly different (p>0.1), but men outscore women on exams and women outscore men on homework and participation. Second, we compare average posttest scores of men and women who score similarly on the pretest and find that there are no significant differences between men and women's average posttest scores. Finally, we analyze other factors in addition to the pretest score that could influence the posttest score and find that gender does not account for a meaningful portion of the variation in posttest scores when a measure of mathematics performance is included. These findings indicate that the gender gap exists in interactive physics classes, but may be due in large part to differences in preparation, background, and math skills as assessed by traditional survey instruments.

TRAFFIC EMISSION IMPACTS ON AIR QUALITY NEAR LARGE ROADWAYS

EPA Science Inventory

Recent epidemiological studies have examined associations between living near major roads and different health endpoints. They find that populations living, working or going to school near major roads may be at increased risk for a number of adverse health effects. When compare...

Racial and Regional Differences in Age at Menopause in the United States: Findings from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

PubMed Central

Mcknight, Katherine K.; Wellons, Melissa F.; Sites, Cynthia K.; Roth, David L.; Szychowski, Jeff M.; Halanych, Jewell H.; Cushman, Mary; Safford, Monika M.

2011-01-01

Objectives To examine regional and Black-White differences in mean age at self-reported menopause among community-dwelling women in the US. Study Design Cross-sectional survey conducted in the context of the REasons for Geographic And Racial Differences in Stroke and Myocardial Infarction study. Results We studied 22,484 menopausal women. After controlling for covariates, Southern women reported menopause 10.8 months earlier than Northeastern women, 8.4 months earlier than Midwestern women, and 6.0 months earlier than Western women (p<0.05 for all). No difference was observed in menopausal age between Black and White women after controlling for covariates (p=0.69). Conclusions Women in the South report earlier menopause than those in other regions, but the cause remains unclear. Our study's large sample size and adjustment for multiple confounders lends weight to our finding of no racial difference in age at menopause. More study is needed of the implications of these findings with regard to vascular health. PMID:21663888

Men, women…who cares? A population-based study on sex differences and gender roles in empathy and moral cognition

PubMed Central

Baez, Sandra; Flichtentrei, Daniel; Prats, María; Mastandueno, Ricardo; García, Adolfo M.; Cetkovich, Marcelo

2017-01-01

Research on sex differences in empathy has revealed mixed findings. Whereas experimental and neuropsychological measures show no consistent sex effect, self-report data consistently indicates greater empathy in women. However, available results mainly come from separate populations with relatively small samples, which may inflate effect sizes and hinder comparability between both empirical corpora. To elucidate the issue, we conducted two large-scale studies. First, we examined whether sex differences emerge in a large population-based sample (n = 10,802) when empathy is measured with an experimental empathy-for-pain paradigm. Moreover, we investigated the relationship between empathy and moral judgment. In the second study, a subsample (n = 334) completed a self-report empathy questionnaire. Results showed some sex differences in the experimental paradigm, but with minuscule effect sizes. Conversely, women did portray themselves as more empathic through self-reports. In addition, utilitarian responses to moral dilemmas were less frequent in women, although these differences also had small effect sizes. These findings suggest that sex differences in empathy are highly driven by the assessment measure. In particular, self-reports may induce biases leading individuals to assume gender-role stereotypes. Awareness of the role of measurement instruments in this field may hone our understanding of the links between empathy, sex differences, and gender roles. PMID:28632770

Informational and emotional elements in online support groups: a Bayesian approach to large-scale content analysis.

PubMed

Deetjen, Ulrike; Powell, John A

2016-05-01

This research examines the extent to which informational and emotional elements are employed in online support forums for 14 purposively sampled chronic medical conditions and the factors that influence whether posts are of a more informational or emotional nature. Large-scale qualitative data were obtained from Dailystrength.org. Based on a hand-coded training dataset, all posts were classified into informational or emotional using a Bayesian classification algorithm to generalize the findings. Posts that could not be classified with a probability of at least 75% were excluded. The overall tendency toward emotional posts differs by condition: mental health (depression, schizophrenia) and Alzheimer's disease consist of more emotional posts, while informational posts relate more to nonterminal physical conditions (irritable bowel syndrome, diabetes, asthma). There is no gender difference across conditions, although prostate cancer forums are oriented toward informational support, whereas breast cancer forums rather feature emotional support. Across diseases, the best predictors for emotional content are lower age and a higher number of overall posts by the support group member. The results are in line with previous empirical research and unify empirical findings from single/2-condition research. Limitations include the analytical restriction to predefined categories (informational, emotional) through the chosen machine-learning approach. Our findings provide an empirical foundation for building theory on informational versus emotional support across conditions, give insights for practitioners to better understand the role of online support groups for different patients, and show the usefulness of machine-learning approaches to analyze large-scale qualitative health data from online settings. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fast dimension reduction and integrative clustering of multi-omics data using low-rank approximation: application to cancer molecular classification.

PubMed

Wu, Dingming; Wang, Dongfang; Zhang, Michael Q; Gu, Jin

2015-12-01

One major goal of large-scale cancer omics study is to identify molecular subtypes for more accurate cancer diagnoses and treatments. To deal with high-dimensional cancer multi-omics data, a promising strategy is to find an effective low-dimensional subspace of the original data and then cluster cancer samples in the reduced subspace. However, due to data-type diversity and big data volume, few methods can integrative and efficiently find the principal low-dimensional manifold of the high-dimensional cancer multi-omics data. In this study, we proposed a novel low-rank approximation based integrative probabilistic model to fast find the shared principal subspace across multiple data types: the convexity of the low-rank regularized likelihood function of the probabilistic model ensures efficient and stable model fitting. Candidate molecular subtypes can be identified by unsupervised clustering hundreds of cancer samples in the reduced low-dimensional subspace. On testing datasets, our method LRAcluster (low-rank approximation based multi-omics data clustering) runs much faster with better clustering performances than the existing method. Then, we applied LRAcluster on large-scale cancer multi-omics data from TCGA. The pan-cancer analysis results show that the cancers of different tissue origins are generally grouped as independent clusters, except squamous-like carcinomas. While the single cancer type analysis suggests that the omics data have different subtyping abilities for different cancer types. LRAcluster is a very useful method for fast dimension reduction and unsupervised clustering of large-scale multi-omics data. LRAcluster is implemented in R and freely available via http://bioinfo.au.tsinghua.edu.cn/software/lracluster/ .

On the observability of coupled dark energy with cosmic voids

NASA Astrophysics Data System (ADS)

Sutter, P. M.; Carlesi, Edoardo; Wandelt, Benjamin D.; Knebe, Alexander

2015-01-01

Taking N-body simulations with volumes and particle densities tuned to match the sloan digital sky survey DR7 spectroscopic main sample, we assess the ability of current void catalogues to distinguish a model of coupled dark matter-dark energy from Λ cold dark matter cosmology using properties of cosmic voids. Identifying voids with the VIDE toolkit, we find no statistically significant differences in the ellipticities, but find that coupling produces a population of significantly larger voids, possibly explaining the recent result of Tavasoli et al. In addition, we use the universal density profile of Hamaus et al. to quantify the relationship between coupling and density profile shape, finding that the coupling produces broader, shallower, undercompensated profiles for large voids by thinning the walls between adjacent medium-scale voids. We find that these differences are potentially measurable with existing void catalogues once effects from survey geometries and peculiar velocities are taken into account.

Experimental Study of Buoyant-Thermocapillary Convection in a Rectangular Cavity

NASA Technical Reports Server (NTRS)

Braunsfurth, Manfred G.; Homsy, George M.

1996-01-01

The problem of buoyant-thermocapillary convection in cavities is governed by a relatively large number of nondimensional parameters, and there is consequently a large number of different types of flow that can be found in this system. Previous results give disjoint glimpses of a wide variety of qualitatively and quantitatively different results in widely different parts of parameter space. In this study, we report experiments on the primary and secondary instabilities in a geometry with equal aspect ratios in the range from 1 to 8 in both the direction along and perpendicular to the applied temperature gradient. We thus complement previous work which mostly involved either fluid layers of large extent in both directions, or consisted of investigations of strictly two-dimensional disturbances. We observe the primary transition from an essentially two-dimensional flow to steady three-dimensional longitudinal rolls. The critical Marangoni number is found to depend on the aspect ratios of the system, and varies from 4.6 x 10(exp 5) at aspect ratio 2.0 to 5.5 x 10(exp 4) at aspect ratio 3.5. Further, we have investigated the stability of the three-dimensional flow at larger Marangoni numbers, and find a novel oscillatory flow at critical Marangoni numbers of the order of 6 x 10(exp 5). We suggest possible mechanisms which give rise to the oscillation, and find that it is expected to be a relaxation type oscillation.

LiFi based automated shopping assistance application in IoT

NASA Astrophysics Data System (ADS)

Akter, Sharmin; Funke Olanrewaju, Rashidah, Dr; Islam, Thouhedul; Salma

2018-05-01

Urban people minimize shopping time in daily life due to time constrain. From that point of view, the concept of supermarket is being popular while consumers can buy different items from same place. However, customer spends hours and hours to find desired items in a large supermarket. In addition, it’s also required to be queued during payment at counter that is also time consuming. As a result, a customer has to spend 2-3 hours for shopping in a large superstore. This paper proposes an Internet of Things and Li-Fi based automated application for smart phone and web to find items easily during shopping that can save consumer’s time as well as reduce man power in supermarket.

Channeling Consumers to Preferred Providers and the Impact of Status Quo Bias: Does Type of Provider Matter?

PubMed Central

Boonen, Lieke H H M; Donkers, Bas; Schut, Frederik T

2011-01-01

Context To effectively bargain about the price and quality of health services, health insurers need to successfully channel their enrollees. Little is known about consumer sensitivity to different channeling incentives. In particular, the impact of status quo bias, which is expected to differ between different provider types, can play a large role in insurers' channeling ability. Objective To examine consumer sensitivity to channeling strategies and to analyze the impact of status quo bias for different provider types. Data Sources/Study Design With a large-scale discrete choice experiment, we investigate the impact of channeling incentives on choices for pharmacies and general practitioners (GPs). Survey data were obtained among a representative Dutch household panel (n=2,500). Principal Findings Negative financial incentives have a two to three times larger impact on provider choice than positive ones. Positive financial incentives have a relatively small impact on GP choice, while the impact of qualitative incentives is relatively large. Status quo bias has a large impact on provider choice, which is more prominent in the case of GPs than in the case of pharmacies. Conclusion The large impact of the status quo bias makes channeling consumers away from their current providers a daunting task, particularly in the case of GPs. PMID:21029092

Large-Scale Structure and Hyperuniformity of Amorphous Ices

NASA Astrophysics Data System (ADS)

Martelli, Fausto; Torquato, Salvatore; Giovambattista, Nicolas; Car, Roberto

2017-09-01

We investigate the large-scale structure of amorphous ices and transitions between their different forms by quantifying their large-scale density fluctuations. Specifically, we simulate the isothermal compression of low-density amorphous ice (LDA) and hexagonal ice to produce high-density amorphous ice (HDA). Both HDA and LDA are nearly hyperuniform; i.e., they are characterized by an anomalous suppression of large-scale density fluctuations. By contrast, in correspondence with the nonequilibrium phase transitions to HDA, the presence of structural heterogeneities strongly suppresses the hyperuniformity and the system becomes hyposurficial (devoid of "surface-area fluctuations"). Our investigation challenges the largely accepted "frozen-liquid" picture, which views glasses as structurally arrested liquids. Beyond implications for water, our findings enrich our understanding of pressure-induced structural transformations in glasses.

Undergraduate Coursework in Economics: A Survey Perspective

ERIC Educational Resources Information Center

Siegfried, John J.; Walstad, William B.

2014-01-01

Survey results from a large sample of economics departments describe offerings for principles courses, coursework requirements for economics majors, and program augmentations such as capstone courses, senior seminars, and honors programs. Findings are reported for all institutions, and institutions are subdivided into six different categories…

What determines the relationship between color naming, unique hues, and sensory singularities: Illuminations, surfaces, or photoreceptors?

PubMed

Witzel, Christoph; Cinotti, François; O'Regan, J Kevin

2015-01-01

The relationship between the sensory signal of the photoreceptors on one hand and color appearance and language on the other hand is completely unclear. A recent finding established a surprisingly accurate correlation between focal colors, unique hues, and so-called singularities in the laws governing how sensory signals for different surfaces change across illuminations. This article examines how this correlation with singularities depends on reflectances, illuminants, and cone sensitivities. Results show that this correlation holds for a large range of illuminants and for a large range of sensors, including sensors that are fundamentally different from human photoreceptors. In contrast, the spectral characteristics of the reflectance spectra turned out to be the key factor that determines the correlation between focal colors, unique hues, and sensory singularities. These findings suggest that the origins of color appearance and color language may be found in particular characteristics of the reflectance spectra that correspond to focal colors and unique hues.

Victimization by Bullying and Harassment in High School: Findings from the 2005 Youth Risk Behavior Survey in a Southwestern State

ERIC Educational Resources Information Center

Bauman, Sheri

2008-01-01

This study analyzed data on victimization by bullying and harassment on school property in a large, diverse, random sample of high school students in Arizona using data from the 2005 Youth Risk Behavior Survey. No gender differences in frequency of victimization were detected, but differences by grade, Body Mass Index category, academic…

The Effect of Parents' Labor Migration on the Socialization of Adolescents

ERIC Educational Resources Information Center

Lialiugene, I. Iu.; Rupshene, L. A.

2008-01-01

The economic factor is considered primary in temporary labor migrations: when people can find jobs in a country where the standard of living is higher, they are able to earn more money than they would in their home country. In the recent years, differences in pay have been so large that by earning a lot of money in a different country and spending…

Approaching the exa-scale: a real-world evaluation of rendering extremely large data sets

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

Patchett, John M; Ahrens, James P; Lo, Li - Ta

2010-10-15

Extremely large scale analysis is becoming increasingly important as supercomputers and their simulations move from petascale to exascale. The lack of dedicated hardware acceleration for rendering on today's supercomputing platforms motivates our detailed evaluation of the possibility of interactive rendering on the supercomputer. In order to facilitate our understanding of rendering on the supercomputing platform, we focus on scalability of rendering algorithms and architecture envisioned for exascale datasets. To understand tradeoffs for dealing with extremely large datasets, we compare three different rendering algorithms for large polygonal data: software based ray tracing, software based rasterization and hardware accelerated rasterization. We presentmore » a case study of strong and weak scaling of rendering extremely large data on both GPU and CPU based parallel supercomputers using Para View, a parallel visualization tool. Wc use three different data sets: two synthetic and one from a scientific application. At an extreme scale, algorithmic rendering choices make a difference and should be considered while approaching exascale computing, visualization, and analysis. We find software based ray-tracing offers a viable approach for scalable rendering of the projected future massive data sizes.« less

Dual Use of Cigarettes, Little Cigars, Cigarillos, and Large Cigars: Smoking Topography and Toxicant Exposure.

PubMed

Pickworth, Wallace B; Rosenberry, Zachary R; O'Grady, Kevin E; Koszowski, Bartosz

2017-04-01

Smoking topography variables and toxicant exposure (plasma nicotine and exhaled CO) were examined in 3 groups of study participants that smoked both cigarettes and either filtered little cigars (Winchester), cigarillos (Black & Mild), or large cigars (Phillies Blunt). Laboratory ad lib smoking of the cigar products was collected with a smoking puff analyzer; plasma levels of nicotine and exhaled CO were collected before and after smoking. Although there were no statistically significant differences in demographic and cigarette smoking topography among the groups, there were significant differences in how the different cigar products were smoked. Plasma nicotine boost was similar after all products but exhaled CO was greater after the cigarillo and large cigar than the little cigar. Some of the differences were due to the differences in article size but other differences were apparent even after adjustment for the amount of tobacco burned or the mouth intake (puff volume). The topography findings of differences among products challenge the practice of grouping cigars as a single entity in surveys, regulatory decisions, and discussions of toxicant exposure. The results add to the discussion of distinctions among products in the scientific assessment of public health risk and regulatory decisions.

Influence of blocking on Northern European and Western Russian heatwaves in large climate model ensembles

NASA Astrophysics Data System (ADS)

Schaller, N.; Sillmann, J.; Anstey, J.; Fischer, E. M.; Grams, C. M.; Russo, S.

2018-05-01

Better preparedness for summer heatwaves could mitigate their adverse effects on society. This can potentially be attained through an increased understanding of the relationship between heatwaves and one of their main dynamical drivers, atmospheric blocking. In the 1979–2015 period, we find that there is a significant correlation between summer heatwave magnitudes and the number of days influenced by atmospheric blocking in Northern Europe and Western Russia. Using three large global climate model ensembles, we find similar correlations, indicating that these three models are able to represent the relationship between extreme temperature and atmospheric blocking, despite having biases in their simulation of individual climate variables such as temperature or geopotential height. Our results emphasize the need to use large ensembles of different global climate models as single realizations do not always capture this relationship. The three large ensembles further suggest that the relationship between summer heatwaves and atmospheric blocking will not change in the future. This could be used to statistically model heatwaves with atmospheric blocking as a covariate and aid decision-makers in planning disaster risk reduction and adaptation to climate change.

Genome analysis and polar tube firing dynamics of mosquito-infecting microsporidia

USDA-ARS?s Scientific Manuscript database

Microsporidia are highly divergent fungi that are obligate intracellular pathogens of a wide range of host organisms. Here we review recent findings from the genome sequences of mosquito-infecting microsporidian species Edhazardia aedis and Vavraia culicis, which show large differences in genome siz...

Process Mining Online Assessment Data

ERIC Educational Resources Information Center

Pechenizkiy, Mykola; Trcka, Nikola; Vasilyeva, Ekaterina; van der Aalst, Wil; De Bra, Paul

2009-01-01

Traditional data mining techniques have been extensively applied to find interesting patterns, build descriptive and predictive models from large volumes of data accumulated through the use of different information systems. The results of data mining can be used for getting a better understanding of the underlying educational processes, for…

Longitudinal pathways between mental health difficulties and academic performance during middle childhood and early adolescence.

PubMed

Deighton, Jessica; Humphrey, Neil; Belsky, Jay; Boehnke, Jan; Vostanis, Panos; Patalay, Praveetha

2018-03-01

There is a growing appreciation that child functioning in different domains, levels, or systems are interrelated over time. Here, we investigate links between internalizing symptoms, externalizing problems, and academic attainment during middle childhood and early adolescence, drawing on two large data sets (child: mean age 8.7 at enrolment, n = 5,878; adolescent: mean age 11.7, n = 6,388). Using a 2-year cross-lag design, we test three hypotheses - adjustment erosion, academic incompetence, and shared risk - while also examining the moderating influence of gender. Multilevel structural equation models provided consistent evidence of the deleterious effect of externalizing problems on later academic achievement in both cohorts, supporting the adjustment-erosion hypothesis. Evidence supporting the academic-incompetence hypothesis was restricted to the middle childhood cohort, revealing links between early academic failure and later internalizing symptoms. In both cohorts, inclusion of shared-risk variables improved model fit and rendered some previously established cross-lag pathways non-significant. Implications of these findings are discussed, and study strengths and limitations noted. Statement of contribution What is already known on this subject? Longitudinal research and in particular developmental cascades literature make the case for weaker associations between internalizing symptoms and academic performance than between externalizing problems and academic performance. Findings vary in terms of the magnitude and inferred direction of effects. Inconsistencies may be explained by different age ranges, prevalence of small-to-modest sample sizes, and large time lags between measurement points. Gender differences remain underexamined. What does this study add? The present study used cross-lagged models to examine longitudinal associations in age groups (middle child and adolescence) in a large-scale British sample. The large sample size not only allows for improvements on previous measurement models (e.g., allowing the analysis to account for nesting, and estimation of latent variables) but also allows for examination of gender differences. The findings clarify the role of shared-risk factors in accounting for associations between internalizing, externalizing, and academic performance, by demonstrating that shared-risk factors do not fully account for relationships between internalizing, externalizing, and academic achievement. Specifically, some pathways between mental health and academic attainment consistently remain, even after shared-risk variables have been accounted for. Findings also present consistent support for the potential impact of behavioural problems on children's academic attainment. The negative relationship between low academic attainment and subsequent internalizing symptoms for younger children is also noteworthy. © 2017 The British Psychological Society.

Does Size Matter? The Multipolar International Landscape of Nanoscience

PubMed Central

Jensen, Pablo; Kreimer, Pablo

2016-01-01

How do different countries tackle nanoscience research? Are all countries similar except for a trivial size effect, as science is often assumed to be universal? Or does size dictate large differences, as large countries are able to develop activities in all directions of research, while small countries have to specialize in some specific niches? Alternatively, is size irrelevant, as all countries have followed different historical paths, leading to different patterns of specialisation? Here, we develop an original method that uses a bottom-up definition of scientific subfields to map the international structure of any scientific field. Our analysis shows that nanoscience research does not show a universal pattern of specialisation, homothetic of that of a single global leader (e.g., the United States). Instead, we find a multipolar world, with four main ways of doing nanosciences. PMID:27992439

Does Size Matter? The Multipolar International Landscape of Nanoscience.

PubMed

Levin, Luciano; Jensen, Pablo; Kreimer, Pablo

2016-01-01

How do different countries tackle nanoscience research? Are all countries similar except for a trivial size effect, as science is often assumed to be universal? Or does size dictate large differences, as large countries are able to develop activities in all directions of research, while small countries have to specialize in some specific niches? Alternatively, is size irrelevant, as all countries have followed different historical paths, leading to different patterns of specialisation? Here, we develop an original method that uses a bottom-up definition of scientific subfields to map the international structure of any scientific field. Our analysis shows that nanoscience research does not show a universal pattern of specialisation, homothetic of that of a single global leader (e.g., the United States). Instead, we find a multipolar world, with four main ways of doing nanosciences.

A simple method for finding the scattering coefficients of quantum graphs

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

Cottrell, Seth S.

2015-09-15

Quantum walks are roughly analogous to classical random walks, and similar to classical walks they have been used to find new (quantum) algorithms. When studying the behavior of large graphs or combinations of graphs, it is useful to find the response of a subgraph to signals of different frequencies. In doing so, we can replace an entire subgraph with a single vertex with variable scattering coefficients. In this paper, a simple technique for quickly finding the scattering coefficients of any discrete-time quantum graph will be presented. These scattering coefficients can be expressed entirely in terms of the characteristic polynomial ofmore » the graph’s time step operator. This is a marked improvement over previous techniques which have traditionally required finding eigenstates for a given eigenvalue, which is far more computationally costly. With the scattering coefficients we can easily derive the “impulse response” which is the key to predicting the response of a graph to any signal. This gives us a powerful set of tools for rapidly understanding the behavior of graphs or for reducing a large graph into its constituent subgraphs regardless of how they are connected.« less

Comparing the Happiness Effects of Real and On-Line Friends

PubMed Central

Helliwell, John F.; Huang, Haifang

2013-01-01

A recent large Canadian survey permits us to compare face-to-face (‘real-life’) and on-line social networks as sources of subjective well-being. The sample of 5,000 is drawn randomly from an on-line pool of respondents, a group well placed to have and value on-line friendships. We find three key results. First, the number of real-life friends is positively correlated with subjective well-being (SWB) even after controlling for income, demographic variables and personality differences. Doubling the number of friends in real life has an equivalent effect on well-being as a 50% increase in income. Second, the size of online networks is largely uncorrelated with subjective well-being. Third, we find that real-life friends are much more important for people who are single, divorced, separated or widowed than they are for people who are married or living with a partner. Findings from large international surveys (the European Social Surveys 2002–2008) are used to confirm the importance of real-life social networks to SWB; they also indicate a significantly smaller value of social networks to married or partnered couples. PMID:24019875

The evolution of surface magnetic fields in young solar-type stars II: the early main sequence (250-650 Myr)

NASA Astrophysics Data System (ADS)

Folsom, C. P.; Bouvier, J.; Petit, P.; Lèbre, A.; Amard, L.; Palacios, A.; Morin, J.; Donati, J.-F.; Vidotto, A. A.

2018-03-01

There is a large change in surface rotation rates of sun-like stars on the pre-main sequence and early main sequence. Since these stars have dynamo-driven magnetic fields, this implies a strong evolution of their magnetic properties over this time period. The spin-down of these stars is controlled by interactions between stellar and magnetic fields, thus magnetic evolution in turn plays an important role in rotational evolution. We present here the second part of a study investigating the evolution of large-scale surface magnetic fields in this critical time period. We observed stars in open clusters and stellar associations with known ages between 120 and 650 Myr, and used spectropolarimetry and Zeeman Doppler Imaging to characterize their large-scale magnetic field strength and geometry. We report 15 stars with magnetic detections here. These stars have masses from 0.8 to 0.95 M⊙, rotation periods from 0.326 to 10.6 d, and we find large-scale magnetic field strengths from 8.5 to 195 G with a wide range of geometries. We find a clear trend towards decreasing magnetic field strength with age, and a power law decrease in magnetic field strength with Rossby number. There is some tentative evidence for saturation of the large-scale magnetic field strength at Rossby numbers below 0.1, although the saturation point is not yet well defined. Comparing to younger classical T Tauri stars, we support the hypothesis that differences in internal structure produce large differences in observed magnetic fields, however for weak-lined T Tauri stars this is less clear.

Whorfian effects on colour memory are not reliable.

PubMed

Wright, Oliver; Davies, Ian R L; Franklin, Anna

2015-01-01

The Whorfian hypothesis suggests that differences between languages cause differences in cognitive processes. Support for this idea comes from studies that find that patterns of colour memory errors made by speakers of different languages align with differences in colour lexicons. The current study provides a large-scale investigation of the relationship between colour language and colour memory, adopting a cross-linguistic and developmental approach. Colour memory on a delayed matching-to-sample (XAB) task was investigated in 2 language groups with differing colour lexicons, for 3 developmental stages and 2 regions of colour space. Analyses used a Bayesian technique to provide simultaneous assessment of two competing hypotheses (H1-Whorfian effect present, H0-Whorfian effect absent). Results of the analyses consistently favoured H0. The findings suggest that Whorfian effects on colour memory are not reliable and that the importance of such effects should not be overestimated.

Race differences in the relationship between role experiences and well-being.

PubMed

Marcussen, Kristen; Piatt, Liz

2005-07-01

Theory and research generally support the notion that social roles benefit subjective well-being. These conclusions, however, are largely based on studies examining Whites. Studies that have included Blacks have found race differences in the influence of social roles on well-being, yet most of these studies focus on role occupancy. With few exceptions, little attention has been paid to whether there are race differences in how individuals experience their roles, and the extent to which race differences in role experiences relate to differences in well-being. In this article we examine racial variation in the experience of work and family roles. We find that Blacks and Whites are similar in their experiences of role conflict and perceptions of role success and balance, but the association between these experiences and well-being varies, to some extent, by race and gender. The implications of these findings as well as suggestions for future research are discussed.

Compiler-directed cache management in multiprocessors

NASA Technical Reports Server (NTRS)

Cheong, Hoichi; Veidenbaum, Alexander V.

1990-01-01

The necessity of finding alternatives to hardware-based cache coherence strategies for large-scale multiprocessor systems is discussed. Three different software-based strategies sharing the same goals and general approach are presented. They consist of a simple invalidation approach, a fast selective invalidation scheme, and a version control scheme. The strategies are suitable for shared-memory multiprocessor systems with interconnection networks and a large number of processors. Results of trace-driven simulations conducted on numerical benchmark routines to compare the performance of the three schemes are presented.

Anomalously strong observations of PKiKP/PcP amplitude ratios on a global scale

NASA Astrophysics Data System (ADS)

Waszek, Lauren; Deuss, Arwen

2015-07-01

The inner core boundary marks the phase transition between the solid inner core and the fluid outer core. As the site of inner core solidification, the boundary provides insight into the processes generating the seismic structures of the inner core. In particular, it may hold the key to understanding the previously observed hemispherical asymmetry in inner core seismic velocity, anisotropy, and attenuation. Here we use a large PKiKP-PcP amplitude ratio and travel time residual data set to investigate velocity and density contrast properties near the inner core boundary. Although hemispherical structure at the boundary has been proposed by previous inner core studies, we find no evidence for hemispheres in the amplitude ratios or travel time residuals. In addition, we find that the amplitude ratios are much larger than can be explained by variations in density contrast at the inner core boundary or core-mantle boundary. This indicates that PKiKP is primarily observed when it is anomalously large, due to focusing along its raypath. Using data in which PKiKP is not detected above the noise level, we calculate an upper estimate for the inner core boundary (ICB) density contrast of 1.2 kg m-3. The travel time residuals display large regional variations, which differ on long and short length scales. These regions may be explained by large-scale velocity variations in the F layer just above the inner core boundary, and/or small-scale topography of varying magnitude on the ICB, which also causes the large amplitudes. Such differences could arise from localized freezing and melting of the inner core.

Which In- and Out-of-School Factors Explain Variations in Learning across Different Socio Economic Groups? Findings from South Africa

ERIC Educational Resources Information Center

Smith, Michele C.

2011-01-01

Previous studies on the role of the school in influencing attainment in South African schools have concluded that the inequalities which are known to exist in these are still largely due to the legacy of the Apartheid system. More recently, policy focus has been on narrowing the gap between the attainment of different socio-economic groups by…

Libyan Military Power Projection in Sub-Saharan Area.

DTIC Science & Technology

1981-06-12

countries; and where there is a natural linkage, we can find possible contacts in many different spheres, economical, political, ethical, cultural , etc...6th century. The Berber cultural substratem was totally submerged in Libya in the ninth and tenth centuries by large-scale immigration of Arabic...was won mainly against the western world (Italy) with its different culture and religion. The present-day adventure represents something quite new

Inferring general relations between network characteristics from specific network ensembles.

PubMed

Cardanobile, Stefano; Pernice, Volker; Deger, Moritz; Rotter, Stefan

2012-01-01

Different network models have been suggested for the topology underlying complex interactions in natural systems. These models are aimed at replicating specific statistical features encountered in real-world networks. However, it is rarely considered to which degree the results obtained for one particular network class can be extrapolated to real-world networks. We address this issue by comparing different classical and more recently developed network models with respect to their ability to generate networks with large structural variability. In particular, we consider the statistical constraints which the respective construction scheme imposes on the generated networks. After having identified the most variable networks, we address the issue of which constraints are common to all network classes and are thus suitable candidates for being generic statistical laws of complex networks. In fact, we find that generic, not model-related dependencies between different network characteristics do exist. This makes it possible to infer global features from local ones using regression models trained on networks with high generalization power. Our results confirm and extend previous findings regarding the synchronization properties of neural networks. Our method seems especially relevant for large networks, which are difficult to map completely, like the neural networks in the brain. The structure of such large networks cannot be fully sampled with the present technology. Our approach provides a method to estimate global properties of under-sampled networks in good approximation. Finally, we demonstrate on three different data sets (C. elegans neuronal network, R. prowazekii metabolic network, and a network of synonyms extracted from Roget's Thesaurus) that real-world networks have statistical relations compatible with those obtained using regression models.

Who should conduct ethnobotanical studies? Effects of different interviewers in the case of the Chácobo Ethnobotany project, Beni, Bolivia.

PubMed

Paniagua-Zambrana, Narel Y; Bussmann, Rainer W; Hart, Robbie E; Moya-Huanca, Araceli L; Ortiz-Soria, Gere; Ortiz-Vaca, Milton; Ortiz-Álvarez, David; Soria-Morán, Jorge; Soria-Morán, María; Chávez, Saúl; Chávez-Moreno, Bertha; Chávez-Moreno, Gualberto; Roca, Oscar; Siripi, Erlin

2018-01-26

That the answers elicited through interviews may be influenced by the knowledge of the interviewer is accepted across disciplines. However, in ethnobotany, there is little evidence to quantitatively assess what impact this effect may have. We use the results of a large study of traditional ecological knowledge (TEK) of plant use of the Chácobo and Pacahuara of Beni, Bolivia, to explore the effects of interviewer identity and knowledge upon the elicited plant species and uses. The Chácobo are a Panoan speaking tribe of about 1000 members (300+ adults) in Beni, Bolivia. Researchers have collected anthropological and ethnobotanical data from the Chácobo for more than a century. Here, we present a complete ethnobotanical inventory of the entire adult Chácobo population, with interviews and plant collection conducted directly by Chácobo counterparts, with a focus on the effects caused by external interviewers. Within this large study, with a unified training for interviewers, we did find that different interviewers did elicit different knowledge sets, that some interviewers were more likely to elicit knowledge similar to their own, and that participants interviewed multiple times often gave information as different as that from two randomly chosen participants. Despite this, we did not find this effect to be overwhelming-the amount of knowledge an interviewer reported on the research subject had comparatively little effect on the amount of knowledge that interviewer recorded from others, and even those interviewers who tended to elicit similar answers from participants also elicited a large percentage of novel information.

Rotations of large inertial cubes, cuboids, cones, and cylinders in turbulence

NASA Astrophysics Data System (ADS)

Pujara, Nimish; Oehmke, Theresa B.; Bordoloi, Ankur D.; Variano, Evan A.

2018-05-01

We conduct experiments to investigate the rotations of freely moving particles in a homogeneous isotropic turbulent flow. The particles are nearly neutrally buoyant and the particle size exceeds the Kolmogorov scale so that they are too large to be considered passive tracers. Particles of several different shapes are considered including those that break axisymmetry and fore-aft symmetry. We find that regardless of shape the mean-square particle angular velocity scales as deq -4 /3, where de q is the equivalent diameter of a volume-matched sphere. This scaling behavior is consistent with the notion that velocity differences across a length de q in the flow are responsible for particle rotation. We also find that the probability density functions (PDFs) of particle angular velocity collapse for particles of different shapes and similar de q. The significance of these results is that the rotations of an inertial, nonspherical particle are only functions of its volume and not its shape. The magnitude of particle angular velocity appears log-normally distributed and individual Cartesian components show long tails. With increasing de q, the tails of the PDF become less pronounced, meaning that extreme events of angular velocity become less common for larger particles.

Increase of Foreign-Born Engineers in U.S. Studied.

ERIC Educational Resources Information Center

Krieger, James

1988-01-01

Summarizes the report of a National Research Council committee. Reports on three basic findings: the proportion of foreign born engineers in the United States has increased over the last 15 years; the increase is disproportionate in the academic sector; and large numbers of students are culturally different. (CW)

Effect of silhouette color on trap catches of Dendroctonus frontalis (Coleoptera: Scolytidae)

Treesearch

B.L. Strom; R.A. Goyer

2001-01-01

With the exception of responses to semiochemicals, host selection behaviors of D. frontalis are largely unstudied. To better understand the host finding behavior of D. frontalis, and to identify potential visual disruptants, we evaluated the response of D. frontalis to multiple-funnel traps of eight different...

E-Learning in the Corporate University

ERIC Educational Resources Information Center

Homan, Gill; Macpherson, Allan

2005-01-01

Purpose: To explore the development of e-learning within the context of corporate universities with the aim of informing the debate on e-learning and establishing key areas of concern for emerging corporate universities. Design/methodology/approach: Three case reviews of large leading edge organizations in different sectors. Findings: Whilst…

First-Generation Students' Academic Engagement and Retention

ERIC Educational Resources Information Center

Soria, Krista M.; Stebleton, Michael J.

2012-01-01

This study investigates differences in academic engagement and retention between first-generation and non-first-generation undergraduate students. Utilizing the Student Experience in the Research University survey of 1864 first-year students at a large, public research university located in the United States, this study finds that first-generation…

Delving into Data

ERIC Educational Resources Information Center

Cullen, Kevin

2005-01-01

Corporations employ data mining to analyze operations, find trends in recorded information, and look for new opportunities. Libraries are no different. Librarians manage large stores of data--about collections and usage, for example--and they also want to analyze this data to serve their users better. Analysts use data mining to query a data…

Sex differences in brain organization: implications for human communication.

PubMed

Hanske-Petitpierre, V; Chen, A C

1985-12-01

This article reviews current knowledge in two major research domains: sex differences in neuropsychophysiology, and in human communication. An attempt was made to integrate knowledge from several areas of brain research with human communication and to clarify how such a cooperative effort may be beneficial to both fields of study. By combining findings from the area of brain research, a communication paradigm was developed which contends that brain-related sex differences may reside largely in the area of communication of emotion.

The Facial Appearance of CEOs: Faces Signal Selection but Not Performance.

PubMed

Stoker, Janka I; Garretsen, Harry; Spreeuwers, Luuk J

2016-01-01

Research overwhelmingly shows that facial appearance predicts leader selection. However, the evidence on the relevance of faces for actual leader ability and consequently performance is inconclusive. By using a state-of-the-art, objective measure for face recognition, we test the predictive value of CEOs' faces for firm performance in a large sample of faces. We first compare the faces of Fortune500 CEOs with those of US citizens and professors. We find clear confirmation that CEOs do look different when compared to citizens or professors, replicating the finding that faces matter for selection. More importantly, we also find that faces of CEOs of top performing firms do not differ from other CEOs. Based on our advanced face recognition method, our results suggest that facial appearance matters for leader selection but that it does not do so for leader performance.

Universal hydrodynamic flow in holographic planar shock collisions

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

Chesler, Paul M.; Kilbertus, Niki; van der Schee, Wilke

2015-11-20

We study the collision of planar shock waves in AdS 5 as a function of shock profile. In the dual field theory the shock waves describe planar sheets of energy whose collision results in the formation of a plasma which behaves hydrodynamically at late times. We find that the post-collision stress tensor near the light cone exhibits transient non-universal behavior which depends on both the shock width and the precise functional form of the shock profile. However, over a large range of shock widths, including those which yield qualitative different behavior near the future light cone, and for different shockmore » profiles, we find universal behavior in the subsequent hydrodynamic evolution. In addition, we compute the rapidity distribution of produced particles and find it to be well described by a Gaussian.« less

Modelling financial markets with agents competing on different time scales and with different amount of information

NASA Astrophysics Data System (ADS)

Wohlmuth, Johannes; Andersen, Jørgen Vitting

2006-05-01

We use agent-based models to study the competition among investors who use trading strategies with different amount of information and with different time scales. We find that mixing agents that trade on the same time scale but with different amount of information has a stabilizing impact on the large and extreme fluctuations of the market. Traders with the most information are found to be more likely to arbitrage traders who use less information in the decision making. On the other hand, introducing investors who act on two different time scales has a destabilizing effect on the large and extreme price movements, increasing the volatility of the market. Closeness in time scale used in the decision making is found to facilitate the creation of local trends. The larger the overlap in commonly shared information the more the traders in a mixed system with different time scales are found to profit from the presence of traders acting at another time scale than themselves.

Oscillatory mechanisms of process binding in memory.

PubMed

Klimesch, Wolfgang; Freunberger, Roman; Sauseng, Paul

2010-06-01

A central topic in cognitive neuroscience is the question, which processes underlie large scale communication within and between different neural networks. The basic assumption is that oscillatory phase synchronization plays an important role for process binding--the transient linking of different cognitive processes--which may be considered a special type of large scale communication. We investigate this question for memory processes on the basis of different types of oscillatory synchronization mechanisms. The reviewed findings suggest that theta and alpha phase coupling (and phase reorganization) reflect control processes in two large memory systems, a working memory and a complex knowledge system that comprises semantic long-term memory. It is suggested that alpha phase synchronization may be interpreted in terms of processes that coordinate top-down control (a process guided by expectancy to focus on relevant search areas) and access to memory traces (a process leading to the activation of a memory trace). An analogous interpretation is suggested for theta oscillations and the controlled access to episodic memories. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

The Distance Between Mars and Venus: Measuring Global Sex Differences in Personality

PubMed Central

Del Giudice, Marco; Booth, Tom; Irwing, Paul

2012-01-01

Background Sex differences in personality are believed to be comparatively small. However, research in this area has suffered from significant methodological limitations. We advance a set of guidelines for overcoming those limitations: (a) measure personality with a higher resolution than that afforded by the Big Five; (b) estimate sex differences on latent factors; and (c) assess global sex differences with multivariate effect sizes. We then apply these guidelines to a large, representative adult sample, and obtain what is presently the best estimate of global sex differences in personality. Methodology/Principal Findings Personality measures were obtained from a large US sample (N = 10,261) with the 16PF Questionnaire. Multigroup latent variable modeling was used to estimate sex differences on individual personality dimensions, which were then aggregated to yield a multivariate effect size (Mahalanobis D). We found a global effect size D = 2.71, corresponding to an overlap of only 10% between the male and female distributions. Even excluding the factor showing the largest univariate ES, the global effect size was D = 1.71 (24% overlap). These are extremely large differences by psychological standards. Significance The idea that there are only minor differences between the personality profiles of males and females should be rejected as based on inadequate methodology. PMID:22238596

Learning Abilities and Disabilities: Generalist Genes, Specialist Environments.

PubMed

Kovas, Yulia; Plomin, Robert

2007-10-01

Twin studies comparing identical and fraternal twins consistently show substantial genetic influence on individual differences in learning abilities such as reading and mathematics, as well as in other cognitive abilities such as spatial ability and memory. Multivariate genetic research has shown that the same set of genes is largely responsible for genetic influence on these diverse cognitive areas. We call these "generalist genes." What differentiates these abilities is largely the environment, especially nonshared environments that make children growing up in the same family different from one another. These multivariate genetic findings of generalist genes and specialist environments have far-reaching implications for diagnosis and treatment of learning disabilities and for understanding the brain mechanisms that mediate these effects.

Radial sets: interactive visual analysis of large overlapping sets.

PubMed

Alsallakh, Bilal; Aigner, Wolfgang; Miksch, Silvia; Hauser, Helwig

2013-12-01

In many applications, data tables contain multi-valued attributes that often store the memberships of the table entities to multiple sets such as which languages a person masters, which skills an applicant documents, or which features a product comes with. With a growing number of entities, the resulting element-set membership matrix becomes very rich of information about how these sets overlap. Many analysis tasks targeted at set-typed data are concerned with these overlaps as salient features of such data. This paper presents Radial Sets, a novel visual technique to analyze set memberships for a large number of elements. Our technique uses frequency-based representations to enable quickly finding and analyzing different kinds of overlaps between the sets, and relating these overlaps to other attributes of the table entities. Furthermore, it enables various interactions to select elements of interest, find out if they are over-represented in specific sets or overlaps, and if they exhibit a different distribution for a specific attribute compared to the rest of the elements. These interactions allow formulating highly-expressive visual queries on the elements in terms of their set memberships and attribute values. As we demonstrate via two usage scenarios, Radial Sets enable revealing and analyzing a multitude of overlapping patterns between large sets, beyond the limits of state-of-the-art techniques.

How did women count? A note on gender-specific age heaping differences in the sixteenth to nineteenth centuries.

PubMed

Földvári, Peter; Van Leeuwen, Bas; Van Leeuwen-Li, Jieli

2012-01-01

The role of human capital in economic growth is now largely uncontested. One indicator of human capital frequently used for the pre-1900 period is age heaping, which has been increasingly used to measure gender-specific differences. In this note, we find that in some historical samples, married women heap significantly less than unmarried women. This is still true after correcting for possible selection effects. A possible explanation is that a percentage of women adapted their ages to that of their husbands, hence biasing the Whipple index. We find the same effect to a lesser extent for men. Since this bias differs over time and across countries, a consistent comparison of female age heaping should be made by focusing on unmarried women.

Size determines antennal sensitivity and behavioral threshold to odors in bumblebee workers

NASA Astrophysics Data System (ADS)

Spaethe, Johannes; Brockmann, Axel; Halbig, Christine; Tautz, Jürgen

2007-09-01

The eusocial bumblebees exhibit pronounced size variation among workers of the same colony. Differently sized workers engage in different tasks (alloethism); large individuals are found to have a higher probability to leave the colony and search for food, whereas small workers tend to stay inside the nest and attend to nest duties. We investigated the effect of size variation on morphology and physiology of the peripheral olfactory system and the behavioral response thresholds to odors in workers of Bombus terrestris. Number and density of olfactory sensilla on the antennae correlate significantly with worker size. Consistent with these morphological changes, we found that antennal sensitivity to odors increases with body size. Antennae of large individuals show higher electroantennogram responses to a given odor concentration than those of smaller nestmates. This finding indicates that large antennae exhibit an increased capability to catch odor molecules and thus are more sensitive to odors than small antennae. We confirmed this prediction in a dual choice behavioral experiment showing that large workers indeed are able to respond correctly to much lower odor concentrations than small workers. Learning performance in these experiments did not differ between small and large bumblebees. Our results clearly show that, in the social bumblebees, variation in olfactory sensilla number due to size differences among workers strongly affects individual odor sensitivity. We speculate that superior odor sensitivity of large workers has favored size-related division of labor in bumblebee colonies.

Liquidity crises on different time scales

NASA Astrophysics Data System (ADS)

Corradi, Francesco; Zaccaria, Andrea; Pietronero, Luciano

2015-12-01

We present an empirical analysis of the microstructure of financial markets and, in particular, of the static and dynamic properties of liquidity. We find that on relatively large time scales (15 min) large price fluctuations are connected to the failure of the subtle mechanism of compensation between the flows of market and limit orders: in other words, the missed revelation of the latent order book breaks the dynamical equilibrium between the flows, triggering the large price jumps. On smaller time scales (30 s), instead, the static depletion of the limit order book is an indicator of an intrinsic fragility of the system, which is related to a strongly nonlinear enhancement of the response. In order to quantify this phenomenon we introduce a measure of the liquidity imbalance present in the book and we show that it is correlated to both the sign and the magnitude of the next price movement. These findings provide a quantitative definition of the effective liquidity, which proves to be strongly dependent on the considered time scales.

Liquidity crises on different time scales.

PubMed

Corradi, Francesco; Zaccaria, Andrea; Pietronero, Luciano

2015-12-01

We present an empirical analysis of the microstructure of financial markets and, in particular, of the static and dynamic properties of liquidity. We find that on relatively large time scales (15 min) large price fluctuations are connected to the failure of the subtle mechanism of compensation between the flows of market and limit orders: in other words, the missed revelation of the latent order book breaks the dynamical equilibrium between the flows, triggering the large price jumps. On smaller time scales (30 s), instead, the static depletion of the limit order book is an indicator of an intrinsic fragility of the system, which is related to a strongly nonlinear enhancement of the response. In order to quantify this phenomenon we introduce a measure of the liquidity imbalance present in the book and we show that it is correlated to both the sign and the magnitude of the next price movement. These findings provide a quantitative definition of the effective liquidity, which proves to be strongly dependent on the considered time scales.

Planum Temporale Asymmetries Correlate with Corpus Callosum Axon Fiber Density in Chimpanzees (Pan troglodytes)

PubMed Central

Hopkins, William D.; Pilger, John F.; Storz, Rachel; Ambrose, Alex; Hof, Patrick R.; Sherwood, Chet C.

2012-01-01

The corpus callosum (CC) is the major white matter tract that connects the two cerebral hemispheres. Some have theorized that individual differences in behavioral and brain asymmetries are linked to variation in the density of axon fibers that traverse different sections of the CC. In this study, we examined whether variation in axon fiber density in the CC was associated with variation in asymmetries in the planum temporale (PT) in a sample of 20 post-mortem chimpanzee brains. We further tested for sex differences in small and large CC fiber proportions and density in the chimpanzees. We found that the distribution of small and large fibers within the CC of chimpanzees follows a similar pattern to those reported in humans. We also found that chimpanzees with larger asymmetries in the PT had fewer large fibers in the posterior portion of the CC, particularly among females. As has been reported in human brains, the findings reported here indicate that individual differences in brain asymmetries are associated with variation in interhemispheric connectivity as manifest in axon fiber density and size. PMID:22766214

Birth outcomes of male and female patients with infantile hypertrophic pyloric stenosis--a population-based case-control study.

PubMed

Vermes, Gabor; Mátrai, Ákos; Czeizel, Andrew E; Ács, Nándor

2016-01-01

Most of the patients are affected by isolated infantile hypertrophic pyloric stenosis (IHPS) beyond the polygenic predisposition, the other factors in the multifactorial etiology are largely unknown. The main characteristic of IHPS is the robust male predominance, thus the aim of this study was to analyze birth outcomes in males and females whether they are different or not. The study samples included 241 cases with IHPS, 357 matched, and 38,151 population controls without any defect in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. The findings of this case-control study confirmed the well-known strong male excess (85.5%). The mean gestational age was somewhat longer and it is associated with a lower rate of preterm births. Mean birth weight did not show significant differences among the study groups, but the rate of low birthweight was higher in cases with IHPS. However, these differences were found only in males. Thus, intrauterine fetal growth restriction is characteristic only for male cases with IHPS. Our study confirmed the well-known obvious male excess of cases with IHPS, but our findings suggest some differences in birth outcomes of male and female cases. Male cases with IHPS had intrauterine fetal growth restriction while females did not. These data may indicate some differences in the pathogenesis of IHPS in males and females.

Are Some Negotiators Better Than Others? Individual Differences in Bargaining Outcomes

PubMed Central

Elfenbein, Hillary Anger; Curhan, Jared R.; Eisenkraft, Noah; Shirako, Aiwa; Baccaro, Lucio

2008-01-01

The authors address the long-standing mystery of stable individual differences in negotiation performance, on which intuition and conventional wisdom have clashed with inconsistent empirical findings. The present study used the Social Relations Model to examine individual differences directly via consistency in performance across multiple negotiations and to disentangle the roles of both parties within these inherently dyadic interactions. Individual differences explained a substantial 46% of objective performance and 19% of subjective performance in a mixed-motive bargaining exercise. Previous work may have understated the influence of individual differences because conventional research designs require specific traits to be identified and measured. Exploratory analyses of a battery of traits revealed few reliable associations with consistent individual differences in objective performance—except for positive beliefs about negotiation, positive affect, and concern for one's outcome, each of which predicted better performance. Findings suggest that the field has large untapped potential to explain substantial individual differences. Limitations, areas for future research, and practical implications are discussed. PMID:21720453

Time-varying multiplex network: Intralayer and interlayer synchronization

NASA Astrophysics Data System (ADS)

Rakshit, Sarbendu; Majhi, Soumen; Bera, Bidesh K.; Sinha, Sudeshna; Ghosh, Dibakar

2017-12-01

A large class of engineered and natural systems, ranging from transportation networks to neuronal networks, are best represented by multiplex network architectures, namely a network composed of two or more different layers where the mutual interaction in each layer may differ from other layers. Here we consider a multiplex network where the intralayer coupling interactions are switched stochastically with a characteristic frequency. We explore the intralayer and interlayer synchronization of such a time-varying multiplex network. We find that the analytically derived necessary condition for intralayer and interlayer synchronization, obtained by the master stability function approach, is in excellent agreement with our numerical results. Interestingly, we clearly find that the higher frequency of switching links in the layers enhances both intralayer and interlayer synchrony, yielding larger windows of synchronization. Further, we quantify the resilience of synchronous states against random perturbations, using a global stability measure based on the concept of basin stability, and this reveals that intralayer coupling strength is most crucial for determining both intralayer and interlayer synchrony. Lastly, we investigate the robustness of interlayer synchronization against a progressive demultiplexing of the multiplex structure, and we find that for rapid switching of intralayer links, the interlayer synchronization persists even when a large number of interlayer nodes are disconnected.

The scaling structure of the global road network

PubMed Central

Giometto, Andrea; Shai, Saray; Bertuzzo, Enrico; Mucha, Peter J.; Rinaldo, Andrea

2017-01-01

Because of increasing global urbanization and its immediate consequences, including changes in patterns of food demand, circulation and land use, the next century will witness a major increase in the extent of paved roads built worldwide. To model the effects of this increase, it is crucial to understand whether possible self-organized patterns are inherent in the global road network structure. Here, we use the largest updated database comprising all major roads on the Earth, together with global urban and cropland inventories, to suggest that road length distributions within croplands are indistinguishable from urban ones, once rescaled to account for the difference in mean road length. Such similarity extends to road length distributions within urban or agricultural domains of a given area. We find two distinct regimes for the scaling of the mean road length with the associated area, holding in general at small and at large values of the latter. In suitably large urban and cropland domains, we find that mean and total road lengths increase linearly with their domain area, differently from earlier suggestions. Scaling regimes suggest that simple and universal mechanisms regulate urban and cropland road expansion at the global scale. As such, our findings bear implications for global road infrastructure growth based on land-use change and for planning policies sustaining urban expansions. PMID:29134071

Time-varying multiplex network: Intralayer and interlayer synchronization.

PubMed

Rakshit, Sarbendu; Majhi, Soumen; Bera, Bidesh K; Sinha, Sudeshna; Ghosh, Dibakar

2017-12-01

A large class of engineered and natural systems, ranging from transportation networks to neuronal networks, are best represented by multiplex network architectures, namely a network composed of two or more different layers where the mutual interaction in each layer may differ from other layers. Here we consider a multiplex network where the intralayer coupling interactions are switched stochastically with a characteristic frequency. We explore the intralayer and interlayer synchronization of such a time-varying multiplex network. We find that the analytically derived necessary condition for intralayer and interlayer synchronization, obtained by the master stability function approach, is in excellent agreement with our numerical results. Interestingly, we clearly find that the higher frequency of switching links in the layers enhances both intralayer and interlayer synchrony, yielding larger windows of synchronization. Further, we quantify the resilience of synchronous states against random perturbations, using a global stability measure based on the concept of basin stability, and this reveals that intralayer coupling strength is most crucial for determining both intralayer and interlayer synchrony. Lastly, we investigate the robustness of interlayer synchronization against a progressive demultiplexing of the multiplex structure, and we find that for rapid switching of intralayer links, the interlayer synchronization persists even when a large number of interlayer nodes are disconnected.

The scaling structure of the global road network.

PubMed

Strano, Emanuele; Giometto, Andrea; Shai, Saray; Bertuzzo, Enrico; Mucha, Peter J; Rinaldo, Andrea

2017-10-01

Because of increasing global urbanization and its immediate consequences, including changes in patterns of food demand, circulation and land use, the next century will witness a major increase in the extent of paved roads built worldwide. To model the effects of this increase, it is crucial to understand whether possible self-organized patterns are inherent in the global road network structure. Here, we use the largest updated database comprising all major roads on the Earth, together with global urban and cropland inventories, to suggest that road length distributions within croplands are indistinguishable from urban ones, once rescaled to account for the difference in mean road length. Such similarity extends to road length distributions within urban or agricultural domains of a given area. We find two distinct regimes for the scaling of the mean road length with the associated area, holding in general at small and at large values of the latter. In suitably large urban and cropland domains, we find that mean and total road lengths increase linearly with their domain area, differently from earlier suggestions. Scaling regimes suggest that simple and universal mechanisms regulate urban and cropland road expansion at the global scale. As such, our findings bear implications for global road infrastructure growth based on land-use change and for planning policies sustaining urban expansions.

Tracking Resilience to Infections by Mapping Disease Space

PubMed Central

Thomas Tate, Ann; Rath, Poonam; Cumnock, Katherine; Schneider, David S.

2016-01-01

Infected hosts differ in their responses to pathogens; some hosts are resilient and recover their original health, whereas others follow a divergent path and die. To quantitate these differences, we propose mapping the routes infected individuals take through “disease space.” We find that when plotting physiological parameters against each other, many pairs have hysteretic relationships that identify the current location of the host and predict the future route of the infection. These maps can readily be constructed from experimental longitudinal data, and we provide two methods to generate the maps from the cross-sectional data that is commonly gathered in field trials. We hypothesize that resilient hosts tend to take small loops through disease space, whereas nonresilient individuals take large loops. We support this hypothesis with experimental data in mice infected with Plasmodium chabaudi, finding that dying mice trace a large arc in red blood cells (RBCs) by reticulocyte space as compared to surviving mice. We find that human malaria patients who are heterozygous for sickle cell hemoglobin occupy a small area of RBCs by reticulocyte space, suggesting this approach can be used to distinguish resilience in human populations. This technique should be broadly useful in describing the in-host dynamics of infections in both model hosts and patients at both population and individual levels. PMID:27088359

Disputed climate science in the media: do countries matter?

PubMed

Grundmann, Reiner; Scott, Mike

2014-02-01

This article presents findings from a large-scale newspaper analysis of climate change discourses in four developed countries, using corpus linguistics methodology. We map the discourse over time, showing peaks and troughs of attention and explaining their causes. Different connotations of common terms such as global warming and climate change in different countries are analysed. Cluster and key-word analysis show the relative salience of specific words and word combinations during crucial periods. We identify main claims makers and the relative visibility of advocates and sceptics. The main finding is that former are far more prominent in all countries. We also look at the coverage of 'climategate'. Finally, we make reference to existing theoretical frameworks.

Ebola, jobs and economic activity in Liberia

PubMed Central

Bowles, Jeremy; Hjort, Jonas; Melvin, Timothy; Werker, Eric

2016-01-01

Background The 2014 Ebola virus disease (EVD) outbreak in the neighbouring West African countries of Guinea, Liberia and Sierra Leone represents the most significant setback to the region's development in over a decade. This study provides evidence on the extent to which economic activity declined and jobs disappeared in Liberia during the outbreak. Methods To estimate how the level of activity and number of jobs in a given set of firms changed during the outbreak, we use a unique panel data set of registered firms surveyed by the business-development non-profit organisation, Building Markets. We also compare the change in economic activity during the outbreak, across regions of the country that had more versus fewer Ebola cases in a difference-in-differences approach. Findings We find a large decrease in economic activity and jobs in all of Liberia during the Ebola outbreak, and an especially large decline in Monrovia. Outside of Monrovia, the restaurants, and food and beverages sectors have suffered the most among the surveyed sectors, and in Monrovia, the construction and restaurant sectors have shed the most employees, while the food and beverages sectors experienced the largest drop in new contracts. We find little association between the incidence of Ebola cases and declines in economic activity outside of Monrovia. Conclusions If the large decline in economic activity that occurred during the Ebola outbreak persists, a focus on economic recovery may need to be added to the efforts to rebuild and support the healthcare system in order for Liberia to regain its footing. PMID:26438188

Modulation of Small-scale Turbulence Structure by Large-scale Motions in the Absence of Direct Energy Transfer.

NASA Astrophysics Data System (ADS)

Brasseur, James G.; Juneja, Anurag

1996-11-01

Previous DNS studies indicate that small-scale structure can be directly altered through ``distant'' dynamical interactions by energetic forcing of the large scales. To remove the possibility of stimulating energy transfer between the large- and small-scale motions in these long-range interactions, we here perturb the large scale structure without altering its energy content by suddenly altering only the phases of large-scale Fourier modes. Scale-dependent changes in turbulence structure appear as a non zero difference field between two simulations from identical initial conditions of isotropic decaying turbulence, one perturbed and one unperturbed. We find that the large-scale phase perturbations leave the evolution of the energy spectrum virtually unchanged relative to the unperturbed turbulence. The difference field, on the other hand, is strongly affected by the perturbation. Most importantly, the time scale τ characterizing the change in in turbulence structure at spatial scale r shortly after initiating a change in large-scale structure decreases with decreasing turbulence scale r. Thus, structural information is transferred directly from the large- to the smallest-scale motions in the absence of direct energy transfer---a long-range effect which cannot be explained by a linear mechanism such as rapid distortion theory. * Supported by ARO grant DAAL03-92-G-0117

Dietary Differences in Male Workers among Smaller Occupational Groups within Large Occupational Categories: Findings from the Japan Environment and Children's Study (JECS).

PubMed

Tanaka, Rie; Tsuji, Mayumi; Senju, Ayako; Kusuhara, Koichi; Kawamoto, Toshihiro

2018-05-11

Studies examining workers' diet according to smaller occupational groups within "large occupational categories" are sparse. The aim of this study was to examine the potential differences in workers' diets based on the classification of workers into smaller occupational groups that comprise "large occupational categories". The subjects of this study were working fathers who had participated in the Japan Environment and Children's Study (N = 38,656). Energy and nutrient intake were calculated based on data collected from the Food Frequency Questionnaire. Occupations were classified according to the Japanese Standard Occupational Classification. Logistic regression analyses were performed to examine the adherence to current dietary recommendations within smaller occupational groups. In particular, significant differences were observed among the categorical groups of "professional and engineering workers", "service workers", and "agricultural, forestry, and fishery workers". In "professional and engineering workers", teachers showed higher odds of adherence to calcium intake recommendations compared with nurses (OR, 2.54; 95% CI, 2.02⁻3.14; p < 0.001). In "agricultural, forestry, and fishery workers", agriculture workers showed higher odds of adherence to calcium (OR, 2.15; 95% CI, 1.46⁻3.15; p < 0.001) and vitamin C (OR 1.90, 95% CI 1.31⁻2.74, p = 0.001) intake recommendations compared with forestry and fishery workers. These findings may be beneficial from a research perspective as well as in the development of more effective techniques to improve workers' diet and health.

Does a ban on informal health providers save lives? Evidence from Malawi

PubMed Central

Godlonton, Susan; Okeke, Edward N.

2015-01-01

Informal health providers ranging from drug vendors to traditional healers account for a large fraction of health care provision in developing countries. They are, however, largely unlicensed and unregulated leading to concern that they provide ineffective and, in some cases, even harmful care. A new and controversial policy tool that has been proposed to alter household health seeking behavior is an outright ban on these informal providers. The theoretical effects of such a ban are ambiguous. In this paper, we study the effect of a ban on informal (traditional) birth attendants imposed by the Malawi government in 2007. To measure the effect of the ban, we use a difference-in-difference strategy exploiting variation across time and space in the intensity of exposure to the ban. Our most conservative estimates suggest that the ban decreased use of traditional attendants by about 15 percentage points. Approximately three quarters of this decline can be attributed to an increase in use of the formal sector and the remainder is accounted for by an increase in relative/friend-attended births. Despite the rather large shift from the informal to the formal sector, we do not find any evidence of a statistically significant reduction in newborn mortality on average. The results are robust to a triple difference specification using young children as a control group. We examine several explanations for this result and find evidence consistent with quality of formal care acting as a constraint on improvements in newborn health. PMID:26681821

Inter-Arm Difference in Brachial Blood Pressure in the General Population of Koreans.

PubMed

Song, Bo Mi; Kim, Hyeon Chang; Shim, Jee-Seon; Lee, Myung Ha; Choi, Dong Phil

2016-05-01

We investigated the inter-arm difference in blood pressure of the general Korean population to identify associated factors. A total of 806 participants aged 30 to 64 years without history of major cardiovascular disease were analyzed in this cross-sectional study. They participated in the Cardiovascular and Metabolic Disease Etiology Research Center cohort study that began in 2013. Brachial blood pressure was measured simultaneously for both arms using an automated oscillometric device equipped with two cuffs in seated position. After five minutes of rest, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured three times. The average of the three measurements was used for analysis. Multivariate logistic regression models were used to identify factors associated with inter-arm differences in blood pressure. The mean inter-arm difference was 3.3 mmHg for SBP and 2.0 mmHg for DBP. Large inter-arm differences (≥10 mmHg) in SBP and in DBP were found in 3.7% and 0.9% of subjects, respectively. A large inter-arm difference in SBP was associated with mean SBP (p=0.002) and C-reactive protein (p=0.014) while a large inter-arm different in DBP was only associated with body mass index (p=0.015). Sex, age, and anti-hypertensive medication use were not associated with differences in inter-arm blood pressure. Large inter-arm difference in blood pressure is only present in a small portion of healthy Korean adults. Our findings suggest that high SBP, chronic inflammation, and obesity may be associated with larger difference in inter-arm blood pressure.

Macroecology of unicellular organisms - patterns and processes.

PubMed

Soininen, Janne

2012-02-01

Macroecology examines the relationship between organisms and their environment at large spatial (and temporal) scales. Typically, macroecologists explain the large-scale patterns of abundance, distribution and diversity. Despite the difficulties in sampling and characterizing microbial diversity, macroecologists have recently also been interested in unicellular organisms. Here, I review the current advances made in microbial macroecology, as well as discuss related ecosystem functions. Overall, it seems that microorganisms suit surprisingly well to known species abundance distributions and show positive relationship between distribution and adundance. Microbial species-area and distance-decay relationships tend to be weaker than for macroorganisms, but nonetheless significant. Few findings on altitudinal gradients in unicellular taxa seem to differ greatly from corresponding findings for larger taxa, whereas latitudinal gradients among microorganisms have either been clearly evident or absent depending on the context. Literature also strongly emphasizes the role of spatial scale for the patterns of diversity and suggests that patterns are affected by species traits as well as ecosystem characteristics. Finally, I discuss the large role of local biotic and abiotic variables driving the community assembly in unicellular taxa and eventually dictating how multiple ecosystem processes are performed. Present review highlights the fact that most microorganisms may not differ fundamentally from larger taxa in their large-scale distribution patterns. Yet, review also shows that many aspects of microbial macroecology are still relatively poorly understood and specific patterns depend on focal taxa and ecosystem concerned. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Extremely large magnetoresistance and Kohler's rule in PdSn 4 : A complete study of thermodynamic, transport, and band-structure properties

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

Jo, Na Hyun; Wu, Yun; Wang, Lin-Lin

The recently discovered material PtSn 4 is known to exhibit extremely large magnetoresistance (XMR) that also manifests Dirac arc nodes on the surface. PdSn 4 is isostructural to PtSn 4 with the same electron count. Here, we report on the physical properties of high-quality single crystals of PdSn 4 including specific heat, temperature- and magnetic-field-dependent resistivity and magnetization, and electronic band-structure properties obtained from angle-resolved photoemission spectroscopy (ARPES). We observe that PdSn 4 has physical properties that are qualitatively similar to those of PtSn 4 , but find also pronounced differences. Importantly, the Dirac arc node surface state of PtSnmore » 4 is gapped out for PdSn 4. By comparing these similar compounds, we address the origin of the extremely large magnetoresistance in PdSn 4 and PtSn 4; based on detailed analysis of the magnetoresistivity ρ ( H , T ) , we conclude that neither the carrier compensation nor the Dirac arc node surface state are the primary reason for the extremely large magnetoresistance. On the other hand, we also find that, surprisingly, Kohler's rule scaling of the magnetoresistance, which describes a self-similarity of the field-induced orbital electronic motion across different length scales and is derived for a simple electronic response of metals to an applied magnetic field is obeyed over the full range of temperatures and field strengths that we explore.« less

Extremely large magnetoresistance and Kohler's rule in PdSn 4 : A complete study of thermodynamic, transport, and band-structure properties

DOE PAGES

Jo, Na Hyun; Wu, Yun; Wang, Lin-Lin; ...

2017-10-27

The recently discovered material PtSn 4 is known to exhibit extremely large magnetoresistance (XMR) that also manifests Dirac arc nodes on the surface. PdSn 4 is isostructural to PtSn 4 with the same electron count. Here, we report on the physical properties of high-quality single crystals of PdSn 4 including specific heat, temperature- and magnetic-field-dependent resistivity and magnetization, and electronic band-structure properties obtained from angle-resolved photoemission spectroscopy (ARPES). We observe that PdSn 4 has physical properties that are qualitatively similar to those of PtSn 4 , but find also pronounced differences. Importantly, the Dirac arc node surface state of PtSnmore » 4 is gapped out for PdSn 4. By comparing these similar compounds, we address the origin of the extremely large magnetoresistance in PdSn 4 and PtSn 4; based on detailed analysis of the magnetoresistivity ρ ( H , T ) , we conclude that neither the carrier compensation nor the Dirac arc node surface state are the primary reason for the extremely large magnetoresistance. On the other hand, we also find that, surprisingly, Kohler's rule scaling of the magnetoresistance, which describes a self-similarity of the field-induced orbital electronic motion across different length scales and is derived for a simple electronic response of metals to an applied magnetic field is obeyed over the full range of temperatures and field strengths that we explore.« less

Illness related wage and productivity losses: Valuing 'presenteeism'.

PubMed

Zhang, Wei; Sun, Huiying; Woodcock, Simon; Anis, Aslam

2015-12-01

One source of productivity loss due to illness is the reduced "quantity" or "quality" of labor input while working, often referred to as presenteeism. Illness-related presenteeism has been found to be potentially more costly than absenteeism. To value presenteeism, existing methods use wages as a proxy for marginal productivity at the firm level. However, wage may not equal marginal productivity in some scenarios. One instance is when a job involves team production and perfect substitutes for workers are not readily available. Using a Canadian linked employer-employee survey (2001-2005), we test whether relative wage equals relative marginal productivity among team workers and non-team workers with different frequencies of presenteeism (reduction at work due to illness). For the pooled cross-sectional estimates (2001, 2003, 2005) we obtain 13,755 observations with 6842 unique workplaces. There are 6490 observations for the first differences estimates from the odd years and 5263 observations for the first differences estimates from 2001 to 2002 and 2003 to 2004. We find that in both small and large firms, team workers with frequent reductions at work are less productive but earn similarly compared with non-team workers without reductions. We also find that in small firms, workers with occasional work reductions are more productive than workers without reductions, but the reverse is true in large firms. The study findings partially support the literature stating that productivity loss resulting from employee presenteeism could exceed wages if team work is involved. Copyright © 2015 Elsevier Ltd. All rights reserved.

Materialism and life satisfaction: the role of religion.

PubMed

Rakrachakarn, Varapa; Moschis, George P; Ong, Fon Sim; Shannon, Randall

2015-04-01

This study examines the role of religion and religiosity in the relationship between materialism and life satisfaction. The findings suggests that religion may be a key factor in understanding differences in findings of previous studies regarding the inverserelationship found in the vast majority of previous studies. Based on a large-scale study in Malaysia—a country comprised of several religious subcultures (mainly Muslims, Buddhists, and Hindus), the findings suggest that the influence of religiosity on materialism and life satisfaction is stronger among Malays than among Chinese and Indians, and life satisfaction partially mediates the relationship between religiosity and materialism. The paper discusses implications for theory development and further research.

Confined disordered strictly jammed binary sphere packings

NASA Astrophysics Data System (ADS)

Chen, D.; Torquato, S.

2015-12-01

Disordered jammed packings under confinement have received considerably less attention than their bulk counterparts and yet arise in a variety of practical situations. In this work, we study binary sphere packings that are confined between two parallel hard planes and generalize the Torquato-Jiao (TJ) sequential linear programming algorithm [Phys. Rev. E 82, 061302 (2010), 10.1103/PhysRevE.82.061302] to obtain putative maximally random jammed (MRJ) packings that are exactly isostatic with high fidelity over a large range of plane separation distances H , small to large sphere radius ratio α , and small sphere relative concentration x . We find that packing characteristics can be substantially different from their bulk analogs, which is due to what we term "confinement frustration." Rattlers in confined packings are generally more prevalent than those in their bulk counterparts. We observe that packing fraction, rattler fraction, and degree of disorder of MRJ packings generally increase with H , though exceptions exist. Discontinuities in the packing characteristics as H varies in the vicinity of certain values of H are due to associated discontinuous transitions between different jammed states. When the plane separation distance is on the order of two large-sphere diameters or less, the packings exhibit salient two-dimensional features; when the plane separation distance exceeds about 30 large-sphere diameters, the packings approach three-dimensional bulk packings. As the size contrast increases (as α decreases), the rattler fraction dramatically increases due to what we call "size-disparity" frustration. We find that at intermediate α and when x is about 0.5 (50-50 mixture), the disorder of packings is maximized, as measured by an order metric ψ that is based on the number density fluctuations in the direction perpendicular to the hard walls. We also apply the local volume-fraction variance στ2(R ) to characterize confined packings and find that these packings possess essentially the same level of hyperuniformity as their bulk counterparts. Our findings are generally relevant to confined packings that arise in biology (e.g., structural color in birds and insects) and may have implications for the creation of high-density powders and improved battery designs.

United by Faith? Race/Ethnicity, Congregational Diversity, and Explanations of Racial Inequality

PubMed Central

Cobb, Ryon J.; Perry, Samuel L.; Dougherty, Kevin D.

2016-01-01

This study examines the extent to which the racial composition of a congregation moderates explanations for Black/White inequality among White, Black, and Hispanic congregants. Using nationally representative data from General Social Surveys and National Congregations Studies, we find that religiously affiliated Blacks and Hispanics tend to hold different racial attitudes than religiously affiliated Whites, but these differences largely disappear inside multiracial congregations. Importantly, we find that attending a multiracial congregation is unassociated with Whites’ explanations for racial inequality, and Blacks who attend multiracial congregations are actually less likely to affirm structural explanations for Black/White inequality than Blacks in nonmultiracial congregations or Whites in multiracial congregations. We find little evidence that multiracial congregations promote progressive racial views among attendees of any race or ethnicity. Rather, our findings suggest that multiracial congregations (1) leave dominant White racial frames unchallenged, potentially influencing minority attendees to embrace such frames and/or (2) attract racial minorities who are more likely to embrace those frames in the first place. PMID:27429542

Multirelational organization of large-scale social networks in an online world

PubMed Central

Szell, Michael; Lambiotte, Renaud; Thurner, Stefan

2010-01-01

The capacity to collect fingerprints of individuals in online media has revolutionized the way researchers explore human society. Social systems can be seen as a nonlinear superposition of a multitude of complex social networks, where nodes represent individuals and links capture a variety of different social relations. Much emphasis has been put on the network topology of social interactions, however, the multidimensional nature of these interactions has largely been ignored, mostly because of lack of data. Here, for the first time, we analyze a complete, multirelational, large social network of a society consisting of the 300,000 odd players of a massive multiplayer online game. We extract networks of six different types of one-to-one interactions between the players. Three of them carry a positive connotation (friendship, communication, trade), three a negative (enmity, armed aggression, punishment). We first analyze these types of networks as separate entities and find that negative interactions differ from positive interactions by their lower reciprocity, weaker clustering, and fatter-tail degree distribution. We then explore how the interdependence of different network types determines the organization of the social system. In particular, we study correlations and overlap between different types of links and demonstrate the tendency of individuals to play different roles in different networks. As a demonstration of the power of the approach, we present the first empirical large-scale verification of the long-standing structural balance theory, by focusing on the specific multiplex network of friendship and enmity relations. PMID:20643965

Multirelational organization of large-scale social networks in an online world.

PubMed

Szell, Michael; Lambiotte, Renaud; Thurner, Stefan

2010-08-03

The capacity to collect fingerprints of individuals in online media has revolutionized the way researchers explore human society. Social systems can be seen as a nonlinear superposition of a multitude of complex social networks, where nodes represent individuals and links capture a variety of different social relations. Much emphasis has been put on the network topology of social interactions, however, the multidimensional nature of these interactions has largely been ignored, mostly because of lack of data. Here, for the first time, we analyze a complete, multirelational, large social network of a society consisting of the 300,000 odd players of a massive multiplayer online game. We extract networks of six different types of one-to-one interactions between the players. Three of them carry a positive connotation (friendship, communication, trade), three a negative (enmity, armed aggression, punishment). We first analyze these types of networks as separate entities and find that negative interactions differ from positive interactions by their lower reciprocity, weaker clustering, and fatter-tail degree distribution. We then explore how the interdependence of different network types determines the organization of the social system. In particular, we study correlations and overlap between different types of links and demonstrate the tendency of individuals to play different roles in different networks. As a demonstration of the power of the approach, we present the first empirical large-scale verification of the long-standing structural balance theory, by focusing on the specific multiplex network of friendship and enmity relations.

Can Rising Instructional Time Crowd out Student Pro-Social Behaviour? Unintended Consequences of a German High School Reform. CEP Discussion Paper No. 1495

ERIC Educational Resources Information Center

Krekel, Christian

2017-01-01

We study whether raising instructional time can crowd out student pro-social behaviour. To this end, we exploit a large educational reform in Germany that has raised weekly instructional hours for high school students by 12.5% as a quasi-natural experiment. Using a difference-in-differences design, we find that this rise has a negative and…

Dual Use of Cigarettes, Little Cigars, Cigarillos, and Large Cigars: Smoking Topography and Toxicant Exposure

PubMed Central

Pickworth, Wallace B.; Rosenberry, Zachary R.; O’Grady, Kevin E.; Koszowski, Bartosz

2017-01-01

Objective Smoking topography variables and toxicant exposure (plasma nicotine and exhaled CO) were examined in 3 groups of study participants that smoked both cigarettes and either filtered little cigars (Winchester), cigarillos (Black & Mild), or large cigars (Phillies Blunt). Methods Laboratory ad lib smoking of the cigar products was collected with a smoking puff analyzer; plasma levels of nicotine and exhaled CO were collected before and after smoking. Results Although there were no statistically significant differences in demographic and cigarette smoking topography among the groups, there were significant differences in how the different cigar products were smoked. Plasma nicotine boost was similar after all products but exhaled CO was greater after the cigarillo and large cigar than the little cigar. Some of the differences were due to the differences in article size but other differences were apparent even after adjustment for the amount of tobacco burned or the mouth intake (puff volume). Conclusions The topography findings of differences among products challenge the practice of grouping cigars as a single entity in surveys, regulatory decisions, and discussions of toxicant exposure. The results add to the discussion of distinctions among products in the scientific assessment of public health risk and regulatory decisions. PMID:28966952

[Health behaviors by job stress level in large-sized company with male and female workers].

PubMed

Park, Hyunju; Jung, Hye-Sun

2010-12-01

This study was done to investigate differences in health behaviors by job stress level in male and female workers in a large-sized company. Participants were 576 male and 228 female workers who completed questionnaires. Job stress was measured using the 'Short Form Korean Occupational Stress Scale (SF-KOSS)'. Health behaviors included smoking, alcohol consumption, regular exercise, and diet. Frequency, mean, SD, chi-square test, and multivariate logistic regression using SAS version 9.1 were used to analyze data. Smoking, drinking and regular exercise rates were not different by job stress level in male or female workers. Only regular diet was significantly different by job stress level in male and female workers. From multivariate analysis, the alcohol consumption rates for female workers differed by marital status. Regular exercise rate was significantly related to age for male workers and type of employment for female workers. After adjusting for demographic and work-related characteristics, regular diet significantly differed by shift work for male workers and marital status and shift work for female workers. The findings of the study indicate that nursing interventions should be developed to manage job stress to improve diet habits for male and female workers in large-sized companies.

Antibiotics Resistance in Rhizobium: Type, Process, Mechanism and Benefit for Agriculture.

PubMed

Naamala, Judith; Jaiswal, Sanjay K; Dakora, Felix D

2016-06-01

The use of high-quality rhizobial inoculants on agricultural legumes has contributed substantially to the N economy of farming systems through inputs from biological nitrogen fixation (BNF). Large populations of symbiotically effective rhizobia should be available in the rhizosphere for symbiotic BNF with host plants. The rhizobial populations should also be able to compete and infect host plants. However, the rhizosphere comprises large populations of different microorganisms. Some of these microorganisms naturally produce antibiotics which are lethal to susceptible rhizobial populations in the soil. Therefore, intrinsic resistance to antibiotics is a desirable trait for the rhizobial population. It increases the rhizobia's chances of growth, multiplication and persistence in the soil. With a large population of rhizobia in the soil, infectivity of host plants and the subsequent BNF efficiency can be guaranteed. This review, therefore, puts together findings by various researchers on antibiotic resistance in bacteria with the main emphasis on rhizobia. It describes the different modes of action of different antibiotics, the types of antibiotic resistance exhibited by rhizobia, the mechanisms of acquisition of antibiotic resistance in rhizobia and the levels of tolerance of different rhizobial species to different antibiotics.

What can the annual 10Be solar activity reconstructions tell us about historic space weather?

NASA Astrophysics Data System (ADS)

Barnard, Luke; McCracken, Ken G.; Owens, Mat J.; Lockwood, Mike

2018-04-01

Context: Cosmogenic isotopes provide useful estimates of past solar magnetic activity, constraining past space climate with reasonable uncertainty. Much less is known about past space weather conditions. Recent advances in the analysis of 10Be by McCracken & Beer (2015, Sol Phys 290: 305-3069) (MB15) suggest that annually resolved 10Be can be significantly affected by solar energetic particle (SEP) fluxes. This poses a problem, and presents an opportunity, as the accurate quantification of past solar magnetic activity requires the SEP effects to be determined and isolated, whilst doing so might provide a valuable record of past SEP fluxes. Aims: We compare the MB15 reconstruction of the heliospheric magnetic field (HMF), with two independent estimates of the HMF derived from sunspot records and geomagnetic variability. We aim to quantify the differences between the HMF reconstructions, and speculate on the origin of these differences. We test whether the differences between the reconstructions appear to depend on known significant space weather events. Methods: We analyse the distributions of the differences between the HMF reconstructions. We consider how the differences vary as a function of solar cycle phase, and, using a Kolmogorov-Smirnov test, we compare the distributions under the two conditions of whether or not large space weather events were known to have occurred. Results: We find that the MB15 reconstructions are generally marginally smaller in magnitude than the sunspot and geomagnetic HMF reconstructions. This bias varies as a function of solar cycle phase, and is largest in the declining phase of the solar cycle. We find that MB15's excision of the years with very large ground level enhancement (GLE) improves the agreement of the 10Be HMF estimate with the sunspot and geomagnetic reconstructions. We find no statistical evidence that GLEs, in general, affect the MB15 reconstruction, but this analysis is limited by having too few samples. We do find evidence that the MB15 reconstructions appear statistically different in years with great geomagnetic storms.

Overview of large animal myocardial infarction models (review).

PubMed

Lukács, E; Magyari, B; Tóth, L; Petrási, Zs; Repa, I; Koller, A; Horváth, Iván

2012-12-01

There are several experimental models for the in vivo investigation of myocardial infarction (MI) in small (mouse, rat) and large animals (dog, pig, sheep and baboons). The application of large animal models raises ethical concerns, the design of experiments needs longer follow-up times, requiring proper breeding and housing conditions, therefore resulting in higher cost, than in vitro or small animal studies. On the other hand, the relevance of large animal models is very important, since they mostly resemble to human physiological and pathophysiological processes. The first main difference among MI models is the method of induction (open or closed chest, e.g. surgical or catheter based); the second main difference is the presence or absence of reperfusion. The former (i.e. reperfused MI) allows the investigation of reperfusion injury and new catheter based techniques during percutaneous coronary interventions, while the latter (i.e. nonreperfused MI) serves as a traditional coronary occlusion model, to test the effects of new pharmacological agents and biological therapies, as cell therapy. The reperfused and nonreperfused myocardial infarction has different outcomes, regarding left ventricular function, remodelling, subsequent heart failure, aneurysm formation and mortality. Our aim was to review the literature and report our findings regarding experimental MI models, regarding the differences among species, methods, reproducibility and interpretation.

The interplay between gender, race and weight status: self perceptions and social consequences.

PubMed

Fletcher, Jason M

2014-07-01

This paper uses data from nearly 15,000 young adult respondents to the Add Health survey to examine racial and gender differences in the perceptions and social rewards to weight. The data include information on several typically unmeasured domains: self-perceptions of ideal weight, attractiveness ratings, and measured weight information, along with ties to a series of adult outcomes. Results show important gender and racial differences in ideal weight as well as differences for both self-perceived attractiveness and interviewer rated attractiveness. Findings also suggest the existence of large differences in socio-cultural rewards and sanctions for weight status. Black respondents, particularly women, appear to receive lower "obesity penalties" in both their self-perceived and interviewer accessed attractiveness ratings than other groups. These findings suggest the need to consider new classes of policies directed at shifting relative social benefits and consequences to weight status. Copyright © 2012 Elsevier B.V. All rights reserved.

Who by accident? The social morphology of car accidents.

PubMed

Factor, Roni; Yair, Gad; Mahalel, David

2010-09-01

Prior studies in the sociology of accidents have shown that different social groups have different rates of accident involvement. This study extends those studies by implementing Bourdieu's relational perspective of social space to systematically explore the homology between drivers' social characteristics and their involvement in specific types of motor vehicle accident. Using a large database that merges official Israeli road-accident records with socioeconomic data from two censuses, this research maps the social order of road accidents through multiple correspondence analysis. Extending prior studies, the results show that different social groups indeed tend to be involved in motor vehicle accidents of different types and severity. For example, we find that drivers from low socioeconomic backgrounds are overinvolved in severe accidents with fatal outcomes. The new findings reported here shed light on the social regularity of road accidents and expose new facets in the social organization of death. © 2010 Society for Risk Analysis.

Generically large nongaussianity in small multifield inflation

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

Bramante, Joseph

If forthcoming measurements of cosmic photon polarization restrict the primordial tensor-to-scalar ratio to r<0.01, small field inflation will be a principal candidate for the origin of the universe. Here we show that small multifield inflation, without the hybrid mechanism, typically results in large squeezed nongaussianity. Small multifield potentials contain multiple flat field directions, often identified with the gauge invariant field directions in supersymmetric potentials. We find that unless these field directions have equal slopes, large nongaussianity arises. After identifying relevant differences between large and small two-field potentials, we demonstrate that the latter naturally fulfill the Byrnes-Choi-Hall large nongaussianity conditions. Computationsmore » of the primordial power spectrum, spectral index, and squeezed bispectrum, reveal that small two-field models which otherwise match observed primordial perturbations, produce excludably large nongaussianity if the inflatons’ field directions have unequal slopes.« less

Generically large nongaussianity in small multifield inflation

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

Bramante, Joseph, E-mail: josephbramante@gmail.com

If forthcoming measurements of cosmic photon polarization restrict the primordial tensor-to-scalar ratio to r < 0.01, small field inflation will be a principal candidate for the origin of the universe. Here we show that small multifield inflation, without the hybrid mechanism, typically results in large squeezed nongaussianity. Small multifield potentials contain multiple flat field directions, often identified with the gauge invariant field directions in supersymmetric potentials. We find that unless these field directions have equal slopes, large nongaussianity arises. After identifying relevant differences between large and small two-field potentials, we demonstrate that the latter naturally fulfill the Byrnes-Choi-Hall large nongaussianity conditions. Computationsmore » of the primordial power spectrum, spectral index, and squeezed bispectrum, reveal that small two-field models which otherwise match observed primordial perturbations, produce excludably large nongaussianity if the inflatons' field directions have unequal slopes.« less

No One Way: Differentiating School District Leadership and Support for School Improvement

ERIC Educational Resources Information Center

Anderson, Stephen E.; Mascall, Blair; Stiegelbauer, Suzanne; Park, Jaddon

2012-01-01

This article examines findings from a qualitative investigation of how school district administrators in four mid to large sized urban school districts (10,000-50,000) identify and address differences in school performance. The analysis explores the interaction between district policies and actions that centralize and standardize expectations for…

Audubon Mammal Study Program.

ERIC Educational Resources Information Center

National Audubon Society, New York, NY.

Included are an illustrated student reader, "The Story of Mammals," a leaders' guide, a large wall chart picturing 39 North American mammals, and a separate booklet describing the mammals on the wall chart. The student reader presents these main topics: What Is a Mammal?; How Mammals Differ From Each Other; Where, When, and How To Find Mammals;…

An Examination of Parents' and Preschool Workers' Perspectives on Bullying in Preschool

ERIC Educational Resources Information Center

Cameron, David Lansing; Kovac, Velibor Bobo

2016-01-01

Parents (n = 141) and preschool workers (n = 81) completed a survey regarding their perspectives towards: (a) the existence of bullying in preschool, (b) interpretations of bullying, (c) the roles of bullies and victims, and (d) gender differences. Findings suggest that both groups largely believe that bullying occurs in preschool. Excluding…

Linguistic Simplification of Mathematics Items: Effects for Language Minority Students in Germany

ERIC Educational Resources Information Center

Haag, Nicole; Heppt, Birgit; Roppelt, Alexander; Stanat, Petra

2015-01-01

In large-scale assessment studies, language minority students typically obtain lower test scores in mathematics than native speakers. Although this performance difference was related to the linguistic complexity of test items in some studies, other studies did not find linguistically demanding math items to be disproportionally more difficult for…

Old Money: Financial Understanding for Older Adult Learners.

ERIC Educational Resources Information Center

Carlton, Shiela; Soulsby, Jim; Whitelegg, Di

This document discusses policy and practice addressing the need for financial literacy education for older people in the United Kingdom. The discussion is based largely on the findings of survey and focus groups that were conducted to identify the difficulties older people encounter in dealing with different financial services and managing their…

Understanding Social Learning Relations of International Students in a Large Classroom Using Social Network Analysis

ERIC Educational Resources Information Center

Rienties, Bart; Héliot, YingFei; Jindal-Snape, Divya

2013-01-01

A common assumption in higher education is that international students find it difficult to develop learning and friendship relations with host students. When students are placed in a student-centred environment, international students from different cultural backgrounds are "forced" to work together with other students, which allows…

Student Background Factors Influencing Student Achievement in Serbia

ERIC Educational Resources Information Center

Teodorovic, Jelena

2012-01-01

This paper describes student-level findings of the first large-scale comprehensive school effectiveness study of the primary education in Serbia. Twenty-five student-level variables were examined in a three-level HLM model using a study sample of almost 5000 students, over 250 classrooms and over 100 schools. Differences between the students were…

An empirical study of the effect of granting multiple tries for online homework

NASA Astrophysics Data System (ADS)

Kortemeyer, Gerd

2015-07-01

When deploying online homework in physics courses, an important consideration is how many tries learners should be allowed to solve numerical free-response problems. While on the one hand, this number should be large enough to allow learners mastery of concepts and avoid copying, on the other hand, granting too many allowed tries encourages counter-productive behavior. We investigate data from an introductory calculus-based physics course that allowed different numbers of tries in different semesters. It turns out that the probabilities for successfully completing or abandoning problems during a particular try are independent of the number of tries already made, which indicates that students do not learn from their earlier tries. We also find that the probability for successfully completing a problem during a particular try decreases with the number of allowed tries, likely due to increased carelessness or guessing, while the probability to give up on a problem after a particular try is largely independent of the number of allowed tries. These findings lead to a mathematical model for learner usage of multiple tries, which predicts an optimum number of five allowed tries.

Controlling microtube permeability via grafted polymers and solvent quality.

PubMed

Suo, Tongchuan; Whitmore, Mark D

2014-03-21

We examine pressure-driven flow through a microtube with grafted polymers using a "doubly self-consistent field" steady-state theory. Our focus is on the structure of the polymer layer, the tube permeability, and the effects of solvent quality, for different regimes of open and closed tubes. We find that, within experimentally attainable pressure gradients, the flow has very little effect on the grafted layer. However, the polymers, and in particular variations in the solvent quality and cylinder radii, can have large effects on the flow. We find that the permeability can either increase or decrease with either the radius or solvent quality, and we identify the regimes for different behaviors in terms of general parameters that can be used to generalize to other systems. This allows us to identify regimes where the systems are most sensitive to these "tuning" parameters, and we find that they correspond to the boundaries between open and closed tubes identified earlier.

Primary Mucinous Cystadenocarcinoma of the Breast: Cytologic Finding and Expression of MUC5 Are Different from Mucinous Carcinoma.

PubMed

Kim, Sung Eun; Park, Ji Hye; Hong, Soonwon; Koo, Ja Seung; Jeong, Joon; Jung, Woo-Hee

2012-12-01

Mucinous cystadenocarcinoma (MCA) in the breast is a rare neoplasm. There have been 13 cases of primary breast MCA reported. The MCA presents as a large, partially cystic mass in postmenopausal woman with a good prognosis. The microscopic findings resemble those of ovarian, pancreatic, or appendiceal MCA. The aspiration findings showed mucin-containing cell clusters in the background of mucin and necrotic material. The cell clusters had intracytoplasmic mucin displacing atypical nuclei to the periphery. Histologically, the tumor revealed an abundant mucin pool with small floating clusters of mucin-containing tumor cells. There were also small cysts lined by a single layer of tall columnar mucinous cells, resembling those of the uterine endocervix. The cancer cells were positive for mucin (MUC) 5 and negative for MUC2 and MUC6. This mucin profile is different from ordinary mucinous carcinoma and may be a unique characteristic of breast MCA.

The Facial Appearance of CEOs: Faces Signal Selection but Not Performance

PubMed Central

Garretsen, Harry; Spreeuwers, Luuk J.

2016-01-01

Research overwhelmingly shows that facial appearance predicts leader selection. However, the evidence on the relevance of faces for actual leader ability and consequently performance is inconclusive. By using a state-of-the-art, objective measure for face recognition, we test the predictive value of CEOs’ faces for firm performance in a large sample of faces. We first compare the faces of Fortune500 CEOs with those of US citizens and professors. We find clear confirmation that CEOs do look different when compared to citizens or professors, replicating the finding that faces matter for selection. More importantly, we also find that faces of CEOs of top performing firms do not differ from other CEOs. Based on our advanced face recognition method, our results suggest that facial appearance matters for leader selection but that it does not do so for leader performance. PMID:27462986

A curious relationship between Potts glass models

NASA Astrophysics Data System (ADS)

Yamaguchi, Chiaki

2015-08-01

A Potts glass model proposed by Nishimori and Stephen [H. Nishimori, M.J. Stephen, Phys. Rev. B 27, 5644 (1983)] is analyzed by means of the replica mean field theory. This model is a discrete model, has a gauge symmetry, and is called the Potts gauge glass model. By comparing the present results with the results of the conventional Potts glass model, we find the coincidences and differences between the models. We find a coincidence that the property for the Potts glass phase in this model is coincident with that in the conventional model at the mean field level. We find a difference that, unlike in the case of the conventional p-state Potts glass model, this system for large p does not become ferromagnetic at low temperature under a concentration of ferromagnetic interaction. The present results support the act of numerically investigating the present model for study of the Potts glass phase in finite dimensions.

Inter-regional competition and quality in hospital care.

PubMed

Aiura, Hiroshi

2013-06-01

This study analyzes the effect of episode-of-care payment and patient choice on waiting time and the comprehensive quality of hospital care. The study assumes that two hospitals are located in two cities with different population sizes and compete with each other. We find that the comprehensive quality of hospital care as well as waiting time of both hospitals improve with an increase in payment per episode of care. However, we also find that the extent of these improvements differs according to the population size of the cities where the hospitals are located. Under the realistic assumptions that hospitals involve significant labor-intensive work, we find the improvements in comprehensive quality and waiting time in a hospital located in a small city to be greater than those in a hospital located in a large city. The result implies that regional disparity in the quality of hospital care decreases with an increase in payment per episode of care.

Region-Urbanicity Differences in Locus of Control: Social Disadvantage, Structure, or Cultural Exceptionalism?

PubMed

Shifrer, Dara; Sutton, April

2014-11-01

People with internal rather than external locus of control experience better outcomes in multiple domains. Previous studies on spatial differences in control within America only focused on the South, relied on aggregate level data or historical evidence, or did not account for other confounding regional distinctions (such as variation in urbanicity). Using data from the National Education Longitudinal Study, we find differences in adolescents' loci of control depending on their region and urbanicity are largely attributable to differences in their social background, and only minimally to structural differences (i.e., differences in the qualities of adolescents' schools). Differences that persist net of differences across adolescents and their schools suggest the less internal control of rural Southern adolescents, and the more internal control of rural and urban Northeastern adolescents, may be due to cultural distinctions in those areas. Results indicate region is more closely associated than urbanicity with differences in locus of control, with Western and Northeastern cultures seemingly fostering more internal control than Midwestern and Southern cultures. These findings contribute to research on spatial variation in a variety of psychological traits.

Region-Urbanicity Differences in Locus of Control: Social Disadvantage, Structure, or Cultural Exceptionalism?

PubMed Central

Shifrer, Dara; Sutton, April

2014-01-01

People with internal rather than external locus of control experience better outcomes in multiple domains. Previous studies on spatial differences in control within America only focused on the South, relied on aggregate level data or historical evidence, or did not account for other confounding regional distinctions (such as variation in urbanicity). Using data from the National Education Longitudinal Study, we find differences in adolescents' loci of control depending on their region and urbanicity are largely attributable to differences in their social background, and only minimally to structural differences (i.e., differences in the qualities of adolescents' schools). Differences that persist net of differences across adolescents and their schools suggest the less internal control of rural Southern adolescents, and the more internal control of rural and urban Northeastern adolescents, may be due to cultural distinctions in those areas. Results indicate region is more closely associated than urbanicity with differences in locus of control, with Western and Northeastern cultures seemingly fostering more internal control than Midwestern and Southern cultures. These findings contribute to research on spatial variation in a variety of psychological traits. PMID:25382875

Robustness of inflation to inhomogeneous initial conditions

NASA Astrophysics Data System (ADS)

Clough, Katy; Lim, Eugene A.; DiNunno, Brandon S.; Fischler, Willy; Flauger, Raphael; Paban, Sonia

2017-09-01

We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out in the region of the potential that does not support inflation. In the large field case, we confirm previous results that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface is approximately flat. Finally, we consider the large field case with a varying extrinsic curvature K, such that some regions are initially collapsing. We find that this may again lead to local black holes, but overall the spacetime remains inflationary if the spacetime is open, which confirms previous theoretical studies.

A Neural Circuit Mechanism for the Involvements of Dopamine in Effort-Related Choices: Decay of Learned Values, Secondary Effects of Depletion, and Calculation of Temporal Difference Error

PubMed Central

2018-01-01

Abstract Dopamine has been suggested to be crucially involved in effort-related choices. Key findings are that dopamine depletion (i) changed preference for a high-cost, large-reward option to a low-cost, small-reward option, (ii) but not when the large-reward option was also low-cost or the small-reward option gave no reward, (iii) while increasing the latency in all the cases but only transiently, and (iv) that antagonism of either dopamine D1 or D2 receptors also specifically impaired selection of the high-cost, large-reward option. The underlying neural circuit mechanisms remain unclear. Here we show that findings i–iii can be explained by the dopaminergic representation of temporal-difference reward-prediction error (TD-RPE), whose mechanisms have now become clarified, if (1) the synaptic strengths storing the values of actions mildly decay in time and (2) the obtained-reward-representing excitatory input to dopamine neurons increases after dopamine depletion. The former is potentially caused by background neural activity–induced weak synaptic plasticity, and the latter is assumed to occur through post-depletion increase of neural activity in the pedunculopontine nucleus, where neurons representing obtained reward exist and presumably send excitatory projections to dopamine neurons. We further show that finding iv, which is nontrivial given the suggested distinct functions of the D1 and D2 corticostriatal pathways, can also be explained if we additionally assume a proposed mechanism of TD-RPE calculation, in which the D1 and D2 pathways encode the values of actions with a temporal difference. These results suggest a possible circuit mechanism for the involvements of dopamine in effort-related choices and, simultaneously, provide implications for the mechanisms of TD-RPE calculation. PMID:29468191

Musculoskeletal anatomy of the Eurasian lynx, Lynx lynx (Carnivora: Felidae) forelimb: Adaptations to capture large prey?

PubMed

Viranta, Suvi; Lommi, Hanna; Holmala, Katja; Laakkonen, Juha

2016-06-01

Mammalian carnivores adhere to two different feeding strategies relative to their body masses. Large carnivores prey on animals that are the same size or larger than themselves, whereas small carnivores prey on smaller vertebrates and invertebrates. The Eurasian lynx (Lynx lynx) falls in between these two categories. Lynx descend from larger forms that were probably large prey specialists, but during the Pleistocene became predators of small prey. The modern Eurasian lynx may be an evolutionary reversal toward specializing in large prey again. We hypothesized that the musculoskeletal anatomy of lynx should show traits for catching large prey. To test our hypothesis, we dissected the forelimb muscles of six Eurasian lynx individuals and compared our findings to results published for other felids. We measured the bones and compared their dimensions to the published material. Our material displayed a well-developed pectoral girdle musculature with some uniquely extensive muscle attachments. The upper arm musculature resembled that of the pantherine felids and probably the extinct sabertooths, and also the muscles responsible for supination and pronation were similar to those in large cats. The muscles controlling the pollex were well-developed. However, skeletal indices were similar to those of small prey predators. Our findings show that lynx possess the topographic pattern of muscle origin and insertion like in large felids. J. Morphol. 277:753-765, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The effect of work on mental health: does occupation matter?

PubMed

Llena-Nozal, Ana; Lindeboom, Maarten; Portrait, France

2004-10-01

This paper considers the effect of work choices on mental health and looks at whether this differs across occupations. This requires a model that can deal with the endogeneity in the relationship between health, occupation and work choices. We specify such a model and estimate it on a unique UK panel survey. The survey, called the National Child development Survey (NCDS), follows a cohort since their birth in 1958 until age 42. The analyses show us that early childhood health and ability have long lasting consequences for the mental health at the later ages. Females have lower levels of mental health. Mental health deteriorates with age for males and females, but the rate of deterioration is substantially lower for females. We also find that the rate of depreciation is lower when individuals work. For females we find large effects of occupation, for males we do not find this. Employment status is important for males, but not for females. For both genders we find very large effects of the onset of a long-standing illness. The probability of experiencing such an event depends on employment status, occupation and life style variables. Copyright 2004 John Wiley & Sons, Ltd.

Efficacy vs effectiveness trial results of an indicated "model" substance abuse program: implications for public health.

PubMed

Hallfors, Denise; Cho, Hyunsan; Sanchez, Victoria; Khatapoush, Shereen; Kim, Hyung Min; Bauer, Daniel

2006-12-01

The US Department of Education requires schools to choose substance abuse and violence prevention programs that meet standards of effectiveness. The Substance Abuse and Mental Health Services Agency certifies "model" programs that meet this standard. We compared findings from a large, multisite effectiveness trial of 1 model program to its efficacy trial findings, upon which the certification was based. 1370 high-risk youths were randomized to experimental or control groups across 9 high schools in 2 large urban school districts. We used intent-to-treat and on-treatment approaches to examine baseline equivalence, attrition, and group differences in outcomes at the end of the program and at a 6-month follow-up. Positive efficacy trial findings were not replicated in the effectiveness trial. All main effects were either null or worse for the experimental than for the control group. These findings suggest that small efficacy trials conducted by developers provide insufficient evidence of effectiveness. Federal agencies and public health scientists must work together to raise the standards of evidence and ensure that data from new trials are incorporated into ongoing assessments of program effects.

Spatial clustering and halo occupation distribution modelling of local AGN via cross-correlation measurements with 2MASS galaxies

NASA Astrophysics Data System (ADS)

Krumpe, Mirko; Miyaji, Takamitsu; Coil, Alison L.; Aceves, Hector

2018-02-01

We present the clustering properties and halo occupation distribution (HOD) modelling of very low redshift, hard X-ray-detected active galactic nuclei (AGN) using cross-correlation function measurements with Two-Micron All Sky Survey galaxies. Spanning a redshift range of 0.007 < z < 0.037, with a median z = 0.024, we present a precise AGN clustering study of the most local AGN in the Universe. The AGN sample is drawn from the SWIFT/BAT 70-month and INTEGRAL/IBIS eight year all-sky X-ray surveys and contains both type I and type II AGN. We find a large-scale bias for the full AGN sample of b=1.04^{+0.10}_{-0.11}, which corresponds to a typical host dark matter halo mass of M_h^typ=12.84^{+0.22}_{-0.30} h^{-1} M_{⊙}. When split into low and high X-ray luminosity and type I and type II AGN subsamples, we detect no statistically significant differences in the large-scale bias parameters. However, there are differences in the small-scale clustering, which are reflected in the full HOD model results. We find that low and high X-ray luminosity AGN, as well as type I and type II AGN, occupy dark matter haloes differently, with 3.4σ and 4.0σ differences in their mean halo masses, respectively, when split by luminosity and type. The latter finding contradicts a simple orientation-based AGN unification model. As a by-product of our cross-correlation approach, we also present the first HOD model of 2MASS galaxies.

Learning Abilities and Disabilities: Generalist Genes, Specialist Environments

PubMed Central

Kovas, Yulia; Plomin, Robert

2007-01-01

Twin studies comparing identical and fraternal twins consistently show substantial genetic influence on individual differences in learning abilities such as reading and mathematics, as well as in other cognitive abilities such as spatial ability and memory. Multivariate genetic research has shown that the same set of genes is largely responsible for genetic influence on these diverse cognitive areas. We call these “generalist genes.” What differentiates these abilities is largely the environment, especially nonshared environments that make children growing up in the same family different from one another. These multivariate genetic findings of generalist genes and specialist environments have far-reaching implications for diagnosis and treatment of learning disabilities and for understanding the brain mechanisms that mediate these effects. PMID:20351764

Experiments on two- and three-dimensional vortex flows in lid-driven cavities

NASA Astrophysics Data System (ADS)

Siegmann-Hegerfeld, Tanja; Albensoeder, Stefan; Kuhlmann, Hendrik C.

2009-11-01

Vortex flows in one-sided lid-driven cavities with different cross-sectional aspect ratios (γ = 0.26 up to γ = 6.3) are investigated experimentally. In all cases the spanwise aspect ratio λ>>γ is very large and much larger than most previous experiments. Flow-structure visualizations will be presented together with quantitative LDA and PIV measurements. The experimental results are in good agreement with the critical data from numerical stability analyses and with nonlinear simulations. Experimentally, we find four different three-dimensional instabilities. Particular attention is paid to the so-called C4 mode which arises at large cross-sectional aspect ratios. When the spanwise aspect ratio is small the first bifurcation of the C4 mode is strongly imperfect.

Accounting for immunoprecipitation efficiencies in the statistical analysis of ChIP-seq data.

PubMed

Bao, Yanchun; Vinciotti, Veronica; Wit, Ernst; 't Hoen, Peter A C

2013-05-30

ImmunoPrecipitation (IP) efficiencies may vary largely between different antibodies and between repeated experiments with the same antibody. These differences have a large impact on the quality of ChIP-seq data: a more efficient experiment will necessarily lead to a higher signal to background ratio, and therefore to an apparent larger number of enriched regions, compared to a less efficient experiment. In this paper, we show how IP efficiencies can be explicitly accounted for in the joint statistical modelling of ChIP-seq data. We fit a latent mixture model to eight experiments on two proteins, from two laboratories where different antibodies are used for the two proteins. We use the model parameters to estimate the efficiencies of individual experiments, and find that these are clearly different for the different laboratories, and amongst technical replicates from the same lab. When we account for ChIP efficiency, we find more regions bound in the more efficient experiments than in the less efficient ones, at the same false discovery rate. A priori knowledge of the same number of binding sites across experiments can also be included in the model for a more robust detection of differentially bound regions among two different proteins. We propose a statistical model for the detection of enriched and differentially bound regions from multiple ChIP-seq data sets. The framework that we present accounts explicitly for IP efficiencies in ChIP-seq data, and allows to model jointly, rather than individually, replicates and experiments from different proteins, leading to more robust biological conclusions.

OBSERVATIONAL SIGNATURES OF A MASSIVE DISTANT PLANET ON THE SCATTERING DISK

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

Lawler, S. M.; Kavelaars, J. J.; Shankman, C.

The orbital element distribution of trans-Neptunian objects (TNOs) with large pericenters has been suggested to be influenced by the presence of an undetected, large planet at >200 au from the Sun. To find additional observables caused by this scenario, we present here the first detailed emplacement simulation in the presence of a massive ninth planet on the distant Kuiper Belt. We perform 4 Gyr N -body simulations with the currently known solar system planetary architecture, plus a 10  M {sub ⊕} planet with similar orbital parameters to those suggested by Trujillo and Sheppard or Batygin and Brown, and 10{sup 5} testmore » particles in an initial planetesimal disk. We find that including a distant super-Earth-mass planet produces a substantially different orbital distribution for the scattering and detached TNOs, raising the pericenters and inclinations of moderate semimajor axis (50 <  a  < 500 au) objects. We test whether this signature is detectable via a simulator with the observational characteristics of four precisely characterized TNO surveys. We find that the qualitatively very distinct solar system models that include a ninth planet are essentially observationally indistinguishable from an outer solar system produced solely by the four giant planets. We also find that the mass of the Kuiper Belt’s current scattering and detached populations is required to be 3–10 times larger in the presence of an additional planet. We do not find any evidence for clustering of orbital angles in our simulated TNO population. Wide-field, deep surveys targeting inclined high-pericenter objects will be required to distinguish between these different scenarios.« less

Labor supply responses to large social transfers: Longitudinal evidence from South Africa

PubMed Central

Ardington, Cally; Case, Anne; Hosegood, Victoria

2009-01-01

In many parts of the developing world, rural areas exhibit high rates of unemployment and underemployment. Understanding what prevents people from migrating to find better jobs is central to the development process. In this paper, we examine whether binding credit constraints and childcare constraints limit the ability of households to send labor migrants, and whether the arrival of a large, stable source of income – here, the South African old-age pension – helps households to overcome these constraints. Specifically, we quantify the labor supply responses of prime-aged individuals to changes in the presence of pensioners, using longitudinal data collected in KwaZulu-Natal. Our ability to compare households and individuals before and after pension receipt, and pension loss, allows us to control for a host of unobservable household and individual characteristics that may determine labor market behavior. We find that large cash transfers to elderly South Africans lead to increased employment among prime-aged members of their households, a result that is masked in cross-sectional analysis by differences between pension and non-pension households. Pension receipt also influences where this employment takes place. We find large, significant effects on labor migration upon pension arrival. The pension’s impact is attributable both to the increase in household resources it represents, which can be used to stake migrants until they become self-sufficient, and to the presence of pensioners who can care for small children, which allows prime-aged adults to look for work elsewhere. PMID:19750139

Operation of molten carbonate fuel cells with different biogas sources: A challenging approach for field trials

NASA Astrophysics Data System (ADS)

Trogisch, S.; Hoffmann, J.; Daza Bertrand, L.

In the past years research in the molten carbonate fuel cells (MCFC) area has been focusing its efforts on the utilisation of natural gas as fuel (S. Geitmann, Wasserstoff- & Brennstoffzellen-Projekte, 2002, ISBN 3-8311-3280-1). In order to increase the advantages of this technology, an international consortium has worked on the utilisation of biogas as fuel in MCFC. During the 4 years lasting RTD project EFFECTIVE two different gas upgrading systems have been developed and constructed together with two mobile MCFC test beds which were operated at different locations for approximately 2.000-5.000 h in each run with biogas from different origins and quality. The large variety of test locations has enabled to gather a large database for assessing the effect of the different biogas qualities on the complete system consisting of the upgrading and the fuel cell systems. The findings are challenging. This article also aims at giving an overview of the advantages of using biogas as fuel for fuel cells.

Even subtle cultural differences affect face tuning.

PubMed

Pavlova, Marina A; Heiz, Julie; Sokolov, Alexander N; Fallgatter, Andreas J; Barisnikov, Koviljka

2018-01-01

Culture shapes social cognition in many ways. Yet cultural impact on face tuning remains largely unclear. Here typically developing females and males from the French-speaking part of Switzerland were presented with a set of Arcimboldo-like Face-n-Food images composed of food ingredients and in different degree resembling a face. The outcome had been compared with previous findings obtained in young adults of the South-West Germany. In that study, males exhibit higher thresholds for face tuning on the Face-n-Food task than females. In Swiss participants, no gender differences exist in face tuning. Strikingly, males from the French-speaking part of Switzerland possess higher sensitivity to faces than their German peers, whereas no difference in face tuning occurs between females. The outcome indicates that even relatively subtle cultural differences as well as culture by gender interaction can modulate social cognition. Clarification of the nature of cultural impact on face tuning as well as social cognition at large is of substantial value for understanding a wide range of neuropsychiatric and neurodevelopmental conditions.

Different brains process numbers differently: structural bases of individual differences in spatial and nonspatial number representations.

PubMed

Krause, Florian; Lindemann, Oliver; Toni, Ivan; Bekkering, Harold

2014-04-01

A dominant hypothesis on how the brain processes numerical size proposes a spatial representation of numbers as positions on a "mental number line." An alternative hypothesis considers numbers as elements of a generalized representation of sensorimotor-related magnitude, which is not obligatorily spatial. Here we show that individuals' relative use of spatial and nonspatial representations has a cerebral counterpart in the structural organization of the posterior parietal cortex. Interindividual variability in the linkage between numbers and spatial responses (faster left responses to small numbers and right responses to large numbers; spatial-numerical association of response codes effect) correlated with variations in gray matter volume around the right precuneus. Conversely, differences in the disposition to link numbers to force production (faster soft responses to small numbers and hard responses to large numbers) were related to gray matter volume in the left angular gyrus. This finding suggests that numerical cognition relies on multiple mental representations of analogue magnitude using different neural implementations that are linked to individual traits.

Gender differences in sexuality: a meta-analysis.

PubMed

Oliver, M B; Hyde, J S

1993-07-01

This meta-analysis surveyed 177 usable sources that reported data on gender differences on 21 different measures of sexual attitudes and behaviors. The largest gender difference was in incidence of masturbation: Men had the greater incidence (d = .96). There was also a large gender difference in attitudes toward casual sex: Males had considerably more permissive attitudes (d = .81). There were no gender differences in attitudes toward homosexuality or in sexual satisfaction. Most other gender differences were in the small-to-moderate range. Gender differences narrowed from the 1960s to the 1980s for many variables. Chodorow's neoanalytic theory, sociobiology, social learning theory, social role theory, and script theory are discussed in relation to these findings.

The relative persuasiveness of gain-framed and loss-framed messages for encouraging disease prevention behaviors: a meta-analytic review.

PubMed

O'Keefe, Daniel J; Jensen, Jakob D

2007-01-01

A meta-analytic review of 93 studies (N = 21,656) finds that in disease prevention messages, gain-framed appeals, which emphasize the advantages of compliance with the communicator's recommendation, are statistically significantly more persuasive than loss-framed appeals, which emphasize the disadvantages of noncompliance. This difference is quite small (corresponding to r = .03), however, and appears attributable to a relatively large (and statistically significant) effect for messages advocating dental hygiene behaviors. Despite very good statistical power, the analysis finds no statistically significant differences in persuasiveness between gain- and loss-framed messages concerning other preventive actions such as safer-sex behaviors, skin cancer prevention behaviors, or diet and nutrition behaviors.

Inter-Arm Difference in Brachial Blood Pressure in the General Population of Koreans

PubMed Central

Song, Bo Mi; Shim, Jee-Seon; Lee, Myung Ha; Choi, Dong Phil

2016-01-01

Background and Objectives We investigated the inter-arm difference in blood pressure of the general Korean population to identify associated factors. Subjects and Methods A total of 806 participants aged 30 to 64 years without history of major cardiovascular disease were analyzed in this cross-sectional study. They participated in the Cardiovascular and Metabolic Disease Etiology Research Center cohort study that began in 2013. Brachial blood pressure was measured simultaneously for both arms using an automated oscillometric device equipped with two cuffs in seated position. After five minutes of rest, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured three times. The average of the three measurements was used for analysis. Multivariate logistic regression models were used to identify factors associated with inter-arm differences in blood pressure. Results The mean inter-arm difference was 3.3 mmHg for SBP and 2.0 mmHg for DBP. Large inter-arm differences (≥10 mmHg) in SBP and in DBP were found in 3.7% and 0.9% of subjects, respectively. A large inter-arm difference in SBP was associated with mean SBP (p=0.002) and C-reactive protein (p=0.014) while a large inter-arm different in DBP was only associated with body mass index (p=0.015). Sex, age, and anti-hypertensive medication use were not associated with differences in inter-arm blood pressure. Conclusion Large inter-arm difference in blood pressure is only present in a small portion of healthy Korean adults. Our findings suggest that high SBP, chronic inflammation, and obesity may be associated with larger difference in inter-arm blood pressure. PMID:27275174

Comparing Planck and WMAP: Maps, Spectra, and Parameters

NASA Astrophysics Data System (ADS)

Larson, D.; Weiland, J. L.; Hinshaw, G.; Bennett, C. L.

2015-03-01

We examine the consistency of the 9 yr WMAP data and the first-release Planck data. We specifically compare sky maps, power spectra, and the inferred Λ cold dark matter (ΛCDM) cosmological parameters. Residual dipoles are seen in the WMAP and Planck sky map differences, but their amplitudes are consistent within the quoted uncertainties, and they are not large enough to explain the widely noted differences in angular power spectra at higher l. We remove the residual dipoles and use templates to remove residual Galactic foregrounds; after doing so, the residual difference maps exhibit a quadrupole and other large-scale systematic structure. We identify this structure as possibly originating from Planck’s beam sidelobe pick-up, but note that it appears to have insignificant cosmological impact. We develop an extension of the internal linear combination technique to find the minimum-variance difference between the WMAP and Planck sky maps; again we find features that plausibly originate in the Planck data. Lacking access to the Planck time-ordered data we cannot further assess these features. We examine ΛCDM model fits to the angular power spectra and conclude that the ˜2.5% difference in the spectra at multipoles greater than l˜ 100 is significant at the 3-5σ level, depending on how beam uncertainties are handled in the data. We revisit the analysis of WMAP’s beam data to address the power spectrum differences and conclude that previously derived uncertainties are robust and cannot explain the power spectrum differences. In fact, any remaining WMAP errors are most likely to exacerbate the difference. Finally, we examine the consistency of the ΛCDM parameters inferred from each data set taking into account the fact that both experiments observe the same sky, but cover different multipole ranges, apply different sky masks, and have different noise. We find that, while individual parameter values agree within the uncertainties, the six parameters taken together are discrepant at the ˜6σ level, with {χ }2}=56 for 6 degrees of freedom (probability to exceed, PTE = 3× {{10}-10}). The nature of this discrepancy is explored: of the six parameters, {{χ }2} is best improved by marginalizing over {{{Ω}c}{{h}2}, giving {χ }2}=5.2 for 5 degrees of freedom. As an exercise, we find that perturbing the WMAP window function by its dominant beam error profile has little effect on {{{Ω}c}{{h}2}, while perturbing the Planck window function by its corresponding error profile has a much greater effect on {{Ω}c}{{h}2}.

Evaluation of a social franchising and telemedicine programme and the care provided for childhood diarrhoea and pneumonia, Bihar, India

PubMed Central

Giardili, Soledad; Das, Veena; Rabin, Tracy L; Raj, Sunil S; Schwartz, Jeremy I; Seth, Aparna; Goldhaber-Fiebert, Jeremy D; Miller, Grant; Vera-Hernández, Marcos

2017-01-01

Abstract Objective To evaluate the impact on the quality of the care provided for childhood diarrhoea and pneumonia in Bihar, India, of a large-scale, social franchising and telemedicine programme – the World Health Partners’ Sky Program. Methods We investigated changes associated with the programme in the knowledge and performance of health-care providers by carrying out 810 assessments in a representative sample of providers in areas where the programme was and was not implemented. Providers were assessed using hypothetical patient vignettes and the standardized patient method both before and after programme implementation, in 2011 and 2014, respectively. Differences in providers’ performance between implementation and nonimplementation areas were assessed using multivariate difference-in-difference linear regression models. Findings The programme did not significantly improve health-care providers’ knowledge or performance with regard to childhood diarrhoea or pneumonia in Bihar. There was a persistent large gap between knowledge of appropriate care and the care actually delivered. Conclusion Social franchising has received attention globally as a model for delivering high-quality care in rural areas in the developing world but supporting data are scarce. Our findings emphasize the need for sound empirical evidence before social franchising programmes are scaled up. PMID:28479635

Number sense across the lifespan as revealed by a massive Internet-based sample

PubMed Central

Halberda, Justin; Ly, Ryan; Wilmer, Jeremy B.; Naiman, Daniel Q.; Germine, Laura

2012-01-01

It has been difficult to determine how cognitive systems change over the grand time scale of an entire life, as few cognitive systems are well enough understood; observable in infants, adolescents, and adults; and simple enough to measure to empower comparisons across vastly different ages. Here we address this challenge with data from more than 10,000 participants ranging from 11 to 85 years of age and investigate the precision of basic numerical intuitions and their relation to students’ performance in school mathematics across the lifespan. We all share a foundational number sense that has been observed in adults, infants, and nonhuman animals, and that, in humans, is generated by neurons in the intraparietal sulcus. Individual differences in the precision of this evolutionarily ancient number sense may impact school mathematics performance in children; however, we know little of its role beyond childhood. Here we find that population trends suggest that the precision of one’s number sense improves throughout the school-age years, peaking quite late at ∼30 y. Despite this gradual developmental improvement, we find very large individual differences in number sense precision among people of the same age, and these differences relate to school mathematical performance throughout adolescence and the adult years. The large individual differences and prolonged development of number sense, paired with its consistent and specific link to mathematics ability across the age span, hold promise for the impact of educational interventions that target the number sense. PMID:22733748

Verbalizing, Visualizing, and Navigating: The Effect of Strategies on Encoding a Large-Scale Virtual Environment

PubMed Central

Kraemer, David J.M.; Schinazi, Victor R.; Cawkwell, Philip B.; Tekriwal, Anand; Epstein, Russell A.; Thompson-Schill, Sharon L.

2016-01-01

Using novel virtual cities, we investigated the influence of verbal and visual strategies on the encoding of navigation-relevant information in a large-scale virtual environment. In two experiments, participants watched videos of routes through four virtual cities and were subsequently tested on their memory for observed landmarks and on their ability to make judgments regarding the relative directions of the different landmarks along the route. In the first experiment, self-report questionnaires measuring visual and verbal cognitive styles were administered to examine correlations between cognitive styles, landmark recognition, and judgments of relative direction. Results demonstrate a tradeoff in which the verbal cognitive style is more beneficial for recognizing individual landmarks than for judging relative directions between them, whereas the visual cognitive style is more beneficial for judging relative directions than for landmark recognition. In a second experiment, we manipulated the use of verbal and visual strategies by varying task instructions given to separate groups of participants. Results confirm that a verbal strategy benefits landmark memory, whereas a visual strategy benefits judgments of relative direction. The manipulation of strategy by altering task instructions appears to trump individual differences in cognitive style. Taken together, we find that processing different details during route encoding, whether due to individual proclivities (Experiment 1) or task instructions (Experiment 2), results in benefits for different components of navigation relevant information. These findings also highlight the value of considering multiple sources of individual differences as part of spatial cognition investigations. PMID:27668486

Learned perceptual associations influence visuomotor programming under limited conditions: kinematic consistency.

PubMed

Haffenden, Angela M; Goodale, Melvyn A

2002-12-01

Previous findings have suggested that visuomotor programming can make use of learned size information in experimental paradigms where movement kinematics are quite consistent from trial to trial. The present experiment was designed to test whether or not this conclusion could be generalized to a different manipulation of kinematic variability. As in previous work, an association was established between the size and colour of square blocks (e.g. red = large; yellow = small, or vice versa). Associating size and colour in this fashion has been shown to reliably alter the perceived size of two test blocks halfway in size between the large and small blocks: estimations of the test block matched in colour to the group of large blocks are smaller than estimations of the test block matched to the group of small blocks. Subjects grasped the blocks, and on other trials estimated the size of the blocks. These changes in perceived block size were incorporated into grip scaling only when movement kinematics were highly consistent from trial to trial; that is, when the blocks were presented in the same location on each trial. When the blocks were presented in different locations grip scaling remained true to the metrics of the test blocks despite the changes in perceptual estimates of block size. These results support previous findings suggesting that kinematic consistency facilitates the incorporation of learned perceptual information into grip scaling.

Ray craters on Ganymede: Implications for cratering apex-antapex asymmetry and surface modification processes

NASA Astrophysics Data System (ADS)

Xu, Luyuan; Hirata, Naoyuki; Miyamoto, Hideaki

2017-10-01

As the youngest features on Ganymede, ray craters are useful in revealing the sources of recent impactors and surface modification processes on the satellite. We examine craters with D > 10 km on Ganymede from images obtained by the Voyager and Galileo spacecraft to identify ray craters and study their spatial distributions. Furthermore, we carefully select images of appropriate solar and emission angles to obtain unbiased ray crater densities. As a result, we find that the density of large ray craters (D > 25 km) on the bright terrain exhibits an apex-antapex asymmetry, and its degree of asymmetry is much lower than the theoretical estimation for ecliptic comets. For large craters (D > 25 km), ecliptic comets ought to be less important than previously assumed, and a possible explanation is that nearly isotropic comets may play a more important role on Ganymede than previously thought. We also find that small ray craters (10 km < D < 25 km) on the bright terrain and ray craters (D > 10 km) on the dark terrain show no apex-antapex asymmetry. We interpret that the distribution difference between the terrain types comes from preferential thermal sublimation on the dark terrain, while the distribution difference between large and small ray craters suggests that rays of small craters are more readily erased by some surface modification processes, such as micrometeorite gardening.

Exploring the Adult Learning Research Field by Analysing Who Cites Whom

ERIC Educational Resources Information Center

Nylander, Erik; Österlund, Lovisa; Fejes, Andreas

2018-01-01

In this article we report on findings from a large-scale bibliographic study conducted based on the citation practices within the field of research on adult learning. Our data consist of 151,261 citation links between more than 33,000 different authors whose papers were published in five leading international journals in the field of adult…

A Study of Attitudes toward College Student-Athletes: Implications for Faculty-Athletics Engagement

ERIC Educational Resources Information Center

Comeaux, Eddie

2011-01-01

To gauge the differential attitudes of faculty members toward student-athletes at a large Division I-A university, a revised version of the Situational Attitude Scale (SAS) Student-Athlete was administered to 464 faculty members. Findings revealed differences in the attitudes of faculty toward student-athletes by race, gender, and college…

Critical Success Factors for eLearning in Saudi Arabian Universities

ERIC Educational Resources Information Center

Alhabeeb, Abdullah; Rowley, Jennifer

2017-01-01

Purpose: The purpose of this paper is to offer insights into the development of eLearning systems and the perceptions of key players in the management of eLearning systems in three large universities in Saudi Arabia. It establishes the relative importance of different factors and compares these findings with studies conducted elsewhere in the…

School Recognition: Principals, Do You Know Who You Are?

ERIC Educational Resources Information Center

Schoer, Lisa Unger

2014-01-01

For high school and middle school principals, the ability to create and maintain positive recognition and identity both personally and for the school is crucial for support from all stakeholders. Finding proactive ways to do this is not much different than the way a large corporation develops a campaign for a major product. Nine principles for…

The Neuroanatomy of Autism Spectrum Disorder: An Overview of Structural Neuroimaging Findings and Their Translatability to the Clinical Setting

ERIC Educational Resources Information Center

Ecker, Christine

2017-01-01

Autism spectrum disorder is a complex neurodevelopmental disorder, which is accompanied by differences in brain anatomy, functioning and brain connectivity. Due to its neurodevelopmental character, and the large phenotypic heterogeneity among individuals on the autism spectrum, the neurobiology of autism spectrum disorder is inherently difficult…

Finding the Key to Successful L2 Learning in Groups and Individuals

ERIC Educational Resources Information Center

Lowie, Wander; van Dijk, Marijn; Chan, Huiping; Verspoor, Marjolijn

2017-01-01

A large body studies into individual differences in second language learning has shown that success in second language learning is strongly affected by a set of relevant learner characteristics ranging from the age of onset to motivation, aptitude, and personality. Most studies have concentrated on a limited number of learner characteristics and…

"I Spent 1-1/2 Hours Sifting through One Large Box...": Diaries as Information Behavior of the Archives User: Lessons Learned.

ERIC Educational Resources Information Center

Toms, Elaine G.; Duff, Wendy

2002-01-01

This article describes how diaries were implemented in a study of the use of archives and archival finding aids by history graduate students. The issues concerning diary use as a data collection technique are discussed as well as the different types of diaries. (Author)

The Main Sources of Intersubject Variability in Neuronal Activation for Reading Aloud

ERIC Educational Resources Information Center

Kherif, Ferath; Josse, Goulven; Seghier, Mohamed L.; Price, Cathy J.

2009-01-01

The aim of this study was to find the most prominent source of intersubject variability in neuronal activation for reading familiar words aloud. To this end, we collected functional imaging data from a large sample of subjects (n = 76) with different demographic characteristics such as handedness, sex, and age, while reading. The…

Concluding the Series on Evidence-Based Practice: The Spread of Excellence in Child and Adolescent Psychiatry

ERIC Educational Resources Information Center

Hamilton, John D.

2008-01-01

The child and adolescent psychiatry community has been using large systems of information and new technologies to improve its performance.Evidence-based approach is used by practitioners to find and implement feasible therapies and medication. The different procedures involved of evidence-based practice, as used in child and adolescent psychology,…

Does Time-on-Task Estimation Matter? Implications for the Validity of Learning Analytics Findings

ERIC Educational Resources Information Center

Kovanovic, Vitomir; Gaševic, Dragan; Dawson, Shane; Joksimovic, Srecko; Baker, Ryan S.; Hatala, Marek

2015-01-01

With\twidespread adoption of Learning Management Systems (LMS) and other learning technology, large amounts of data--commonly known as trace data--are readily accessible to researchers. Trace data has been extensively used to calculate time that students spend on different learning activities--typically referred to as time-on-task. These measures…

Technology Uptake in Chinese EFL Classes

ERIC Educational Resources Information Center

Li, Li; Walsh, Steve

2011-01-01

This article presents findings from what we believe to be the first large-scale study of its kind on the use of ICT (information and communications technology) in English language classes in China. Participants are 400 EFL (English as a foreign language) teachers from different types of schools in Beijing. The purpose of the study was to examine…

A Forgotten Sector; The Training of Ancillary Staff in Hospitals.

ERIC Educational Resources Information Center

Smith, Duncan N.

A study was made, in England and Wales, of training needs of hospital ancillary staff; it concentrated on a group of hospitals in each of six Hospital Regions. In addition, information was collected at the national level and brief visits were made in other regions. Findings showed large differences in staffing between hospitals of similar types,…

Differential Exposure and Reactivity to Interpersonal Stress Predict Sex Differences in Adolescent Depression

ERIC Educational Resources Information Center

Shih, Josephine H.; Eberhart, Nicole K.; Hammen, Constance L.; Brennan, Patricia A.

2006-01-01

This study tested the hypothesis that higher rates of depression in adolescent girls are explained by their greater exposure and reactivity to stress in the interpersonal domain in a large sample of 15-year-olds. Findings indicate that adolescent girls experienced higher levels of total and interpersonal episodic stress, whereas boys experienced…

The Age Parameters of the Starting Demographic Events across Russian Generations

ERIC Educational Resources Information Center

Mitrofanova, E. S.

2016-01-01

This article presents comparisons of the ages and facts of starting demographic events in Russia based on the findings of three large-scale surveys: the European Social Survey, 2006; the Generations and Gender Survey, 2004, 2007, and 2011; and Person, Family, Society, 2013. This study focuses on the intergenerational and gender differences in the…

Large grain instruction and phonological awareness skill influence rime sensitivity, processing speed, and early decoding skill in adult L2 learners

PubMed Central

Brennan, Christine; Booth, James R.

2016-01-01

Linguistic knowledge, cognitive ability, and instruction influence how adults acquire a second orthography yet it remains unclear how different forms of instruction influence grain size sensitivity and subsequent decoding skill and speed. Thirty-seven monolingual, literate English-speaking adults were trained on a novel artificial orthography given initial instruction that directed attention to either large or small grain size units (i.e., words or letters). We examined how initial instruction influenced processing speed (i.e., reaction time (RT)) and sensitivity to different orthographic grain sizes (i.e., rimes and letters). Directing attention to large grain size units during initial instruction resulted in higher accuracy for rimes, whereas directing attention to smaller grain size units resulted in slower RTs across all measures. Additionally, phonological awareness skill modulated early learning effects, compensating for the limitations of the initial instruction provided. Collectively, these findings suggest that when adults are learning to read a second orthography, consideration should be given to how initial instruction directs attention to different grain sizes and inherent phonological awareness ability. PMID:27829705

The limits of weak selection and large population size in evolutionary game theory.

PubMed

Sample, Christine; Allen, Benjamin

2017-11-01

Evolutionary game theory is a mathematical approach to studying how social behaviors evolve. In many recent works, evolutionary competition between strategies is modeled as a stochastic process in a finite population. In this context, two limits are both mathematically convenient and biologically relevant: weak selection and large population size. These limits can be combined in different ways, leading to potentially different results. We consider two orderings: the [Formula: see text] limit, in which weak selection is applied before the large population limit, and the [Formula: see text] limit, in which the order is reversed. Formal mathematical definitions of the [Formula: see text] and [Formula: see text] limits are provided. Applying these definitions to the Moran process of evolutionary game theory, we obtain asymptotic expressions for fixation probability and conditions for success in these limits. We find that the asymptotic expressions for fixation probability, and the conditions for a strategy to be favored over a neutral mutation, are different in the [Formula: see text] and [Formula: see text] limits. However, the ordering of limits does not affect the conditions for one strategy to be favored over another.

Butterfly magnetoresistance, quasi-2D Dirac Fermi surface and topological phase transition in ZrSiS.

PubMed

Ali, Mazhar N; Schoop, Leslie M; Garg, Chirag; Lippmann, Judith M; Lara, Erik; Lotsch, Bettina; Parkin, Stuart S P

2016-12-01

Magnetoresistance (MR), the change of a material's electrical resistance in response to an applied magnetic field, is a technologically important property that has been the topic of intense study for more than a quarter century. We report the observation of an unusual "butterfly"-shaped titanic angular magnetoresistance (AMR) in the nonmagnetic Dirac material, ZrSiS, which we find to be the most conducting sulfide known, with a 2-K resistivity as low as 48(4) nΩ⋅cm. The MR in ZrSiS is large and positive, reaching nearly 1.8 × 10 5 percent at 9 T and 2 K at a 45° angle between the applied current ( I || a ) and the applied field (90° is H || c ). Approaching 90°, a "dip" is seen in the AMR, which, by analyzing Shubnikov de Haas oscillations at different angles, we find to coincide with a very sharp topological phase transition unlike any seen in other known Dirac/Weyl materials. We find that ZrSiS has a combination of two-dimensional (2D) and 3D Dirac pockets comprising its Fermi surface and that the combination of high-mobility carriers and multiple pockets in ZrSiS allows for large property changes to occur as a function of angle between applied fields. This makes it a promising platform to study the physics stemming from the coexistence of 2D and 3D Dirac electrons as well as opens the door to creating devices focused on switching between different parts of the Fermi surface and different topological states.

Association of vascular physical examination findings and arteriographic lesions in large vessel vasculitis.

PubMed

Grayson, Peter C; Tomasson, Gunnar; Cuthbertson, David; Carette, Simon; Hoffman, Gary S; Khalidi, Nader A; Langford, Carol A; McAlear, Carol A; Monach, Paul A; Seo, Philip; Warrington, Kenneth J; Ytterberg, Steven R; Merkel, Peter A

2012-02-01

To assess the utility of the vascular physical examination to detect arteriographic lesions in patients with established large vessel vasculitis (LVV), including Takayasu's arteritis (TAK) and giant cell arteritis (GCA). In total, 100 patients (TAK = 68, GCA = 32) underwent standardized physical examination and angiography of the carotid, subclavian, and axillary arteries. Sensitivity and specificity were calculated for the association between findings on physical examination focusing on the vascular system (absent pulse, bruit, and blood pressure difference) and arteriographic lesions defined as stenosis, occlusion, or aneurysm. We found 67% of patients had at least 1 abnormality on physical examination (74% TAK, 53% GCA). Arteriographic lesions were seen in 76% of patients (82% TAK, 63% GCA). Individual physical examination findings had poor sensitivity (range 14%-50%) and good-excellent specificity (range 71%-98%) to detect arteriographic lesions. Even when considering physical examination findings in combination, at least 30% of arteriographic lesions were missed. Specificity improved (range 88%-100%) if individual physical examination findings were compared to a broader region of vessels rather than specific anatomically correlated vessels and if ≥ 1 physical examination findings were combined. In patients with established LVV, physical examination alone is worthwhile to detect arterial disease but does not always localize or reveal the full extent of arteriographic lesions. Abnormal vascular system findings on physical examination are highly associated with the presence of arterial lesions, but normal findings on physical examination do not exclude the possibility of arterial disease. Serial angiographic assessment is advisable to monitor arterial disease in patients with established LVV.

Association of Vascular Physical Examination Findings and Arteriographic Lesions in Large Vessel Vasculitis

PubMed Central

GRAYSON, PETER C.; TOMASSON, GUNNAR; CUTHBERTSON, DAVID; CARETTE, SIMON; HOFFMAN, GARY S.; KHALIDI, NADER A.; LANGFORD, CAROL A.; McALEAR, CAROL A.; MONACH, PAUL A.; SEO, PHILIP; WARRINGTON, KENNETH J.; YTTERBERG, STEVEN R.; MERKEL, PETER A.

2013-01-01

Objective To assess the utility of the vascular physical examination to detect arteriographic lesions in patients with established large vessel vasculitis (LVV), including Takayasu’s arteritis (TAK) and giant cell arteritis (GCA). Methods In total, 100 patients (TAK = 68, GCA = 32) underwent standardized physical examination and angiography of the carotid, subclavian, and axillary arteries. Sensitivity and specificity were calculated for the association between findings on physical examination focusing on the vascular system (absent pulse, bruit, and blood pressure difference) and arteriographic lesions defined as stenosis, occlusion, or aneurysm. Results We found 67% of patients had at least 1 abnormality on physical examination (74% TAK, 53% GCA). Arteriographic lesions were seen in 76% of patients (82% TAK, 63% GCA). Individual physical examination findings had poor sensitivity (range 14%–50%) and good-excellent specificity (range 71%–98%) to detect arteriographic lesions. Even when considering physical examination findings in combination, at least 30% of arteriographic lesions were missed. Specificity improved (range 88%–100%) if individual physical examination findings were compared to a broader region of vessels rather than specific anatomically correlated vessels and if ≥ 1 physical examination findings were combined. Conclusion In patients with established LVV, physical examination alone is worthwhile to detect arterial disease but does not always localize or reveal the full extent of arteriographic lesions. Abnormal vascular system findings on physical examination are highly associated with the presence of arterial lesions, but normal findings on physical examination do not exclude the possibility of arterial disease. Serial angiographic assessment is advisable to monitor arterial disease in patients with established LVV. PMID:22174204

Discharge characteristics of biceps brachii motor units at recruitment when older adults sustained an isometric contraction.

PubMed

Pascoe, Michael A; Holmes, Matthew R; Enoka, Roger M

2011-02-01

The purpose of this study was to compare the discharge characteristics of motor units recruited during an isometric contraction that was sustained with the elbow flexor muscles by older adults at target forces that were less than the recruitment threshold force of each isolated motor unit. The discharge times of 27 single motor units were recorded from the biceps brachii in 11 old adults (78.8 ± 5.9 yr). The target force was set at either a relatively small (6.6 ± 3.7% maximum) or large (11.4 ± 4.5% maximum) difference below the recruitment threshold force and the contraction was sustained until the motor unit was recruited and discharged action potentials for about 60 s. The time to recruitment was longer for the large target-force difference (P = 0.001). At recruitment, the motor units discharged repetitively for both target-force differences, which contrasts with data from young adults when motor units discharged intermittently at recruitment for the large difference between recruitment threshold force and target force. The coefficient of variation (CV) for the first five interspike intervals (ISIs) increased from the small (18.7 ± 7.9) to large difference (35.0 ± 10.2%, P = 0.008) for the young adults, but did not differ for the two target force differences for the old adults (26.3 ± 14.7 to 24.0 ± 13.1%, P = 0.610). When analyzed across the discharge duration, the average CV for the ISI decreased similarly for the two target-force differences (P = 0.618) in old adults. These findings contrast with those of young adults and indicate that the integration of synaptic input during sustained contractions differs between young and old adults.

Accumulation mechanisms and the weathering of Antarctic equilibrated ordinary chondrites

NASA Astrophysics Data System (ADS)

Benoit, P. H.; Sears, D. W. G.

1999-06-01

Induced thermoluminescence (TL) is used to quantitatively evaluate the degree of weathering of meteorites found in Antarctica. We find a weak correlation between TL sensitivity and descriptions of weathering in hand specimens, the highly weathered meteorites having lower TL sensitivity than unweathered meteorites. Analysis of samples taken throughout large meteorites shows that the heterogeneity in TL sensitivity within meteorite finds is not large relative to the range exhibited by different weathered meteorites. The TL sensitivity values can be restored by minimal acid washing, suggesting the lower TL sensitivities of weathered meteorites reflects thin weathering rims on mineral grains or coating of these grains by iron oxides produced by hydration and oxidation of metal and sulfides. Small meteorites may tend to be more highly weathered than large meteorites at the Allan Hills ice fields. We find that meteorite fragments >150 g may take up to 300,000 years to reach the highest degrees of weathering, while meteorites <150 g require <40,000 years. However, at other fields, local environmental conditions and variability in terrestrial history are more important in determining weathering than size alone. Weathering correlates poorly with surface exposure duration, presumably because weathering occurs primarily during interglacial periods. The Allan Hills locality has served as a fairly stable surface over the last 100,000 years or so and has efficiently preserved both small and large meteorites. Meteorites from Lewis Cliff, however, have experienced extensive weathering, probably because of increased surface melt water from nearby outcrops. Meteorites from the Elephant Moraine locality tend to exhibit only minor degrees of weathering, but small meteorites are less weathered than large meteorites, which we suggest is due to the loss of small meteorites by aeolian transport.

Stanley Corrsin Award Talk: Fluid Mechanics of Fungi and Slime

NASA Astrophysics Data System (ADS)

Brenner, Michael

2013-11-01

There are interesting fluid mechanics problems everywhere, even in the most lowly and hidden corners of forest floors. Here I discuss some questions we have been working on in recent years involving fungi and slime. A critical issue for the ecology of fungi and slime is nutrient availability: nutrient sources are highly heterogeneous, and strategies are necessary to find food when it runs out. In the fungal phylum Ascomycota, spore dispersal is the primary mechanism for finding new food sources. The defining feature of this phylum is the ascus, a fluid filled sac from which spores are ejected, through a build up in osmotic pressure. We outline the (largely fluid mechanical) design constraints on this ejection strategy, and demonstrate how it provides strong constraints for the diverse morphologies of spores and asci found in nature. The core of the argument revisits a classical problem in elastohydrodynamic lubrication from a different perspective. A completely different strategy for finding new nutrient is found by slime molds and fungi that stretch out - as a single organism- over enormous areas (up to hectares) over forest floors. As a model problem we study the slime mold Physarum polycephalum, which forages with a large network of connected tubes on the forest floors. Localized regions in the network find nutrient sources and then pump the nutrients throughout the entire organism. We discuss fluid mechanical mechanisms for coordinating this transport, which generalize peristalsis to pumping in a heterogeneous network. We give a preliminary discussion to how physarum can detect a nutrient source and pump the nutrient throughout the organism.

Deep 3-GHz observations of the Lockman Hole North with the Very Large Array - I. Source extraction and uncertainty analysis

NASA Astrophysics Data System (ADS)

Vernstrom, T.; Scott, Douglas; Wall, J. V.; Condon, J. J.; Cotton, W. D.; Perley, R. A.

2016-09-01

This is the first of two papers describing the observations and cataloguing of deep 3-GHz observations of the Lockman Hole North using the Karl G. Jansky Very Large Array. The aim of this paper is to investigate, through the use of simulated images, the uncertainties and accuracy of source-finding routines, as well as to quantify systematic effects due to resolution, such as source confusion and source size. While these effects are not new, this work is intended as a particular case study that can be scaled and translated to other surveys. We use the simulations to derive uncertainties in the fitted parameters, as well as bias corrections for the actual catalogue (presented in Paper II). We compare two different source-finding routines, OBIT and AEGEAN, and two different effective resolutions, 8 and 2.75 arcsec. We find that the two routines perform comparably well, with OBIT being slightly better at de-blending sources, but slightly worse at fitting resolved sources. We show that 30-70 per cent of sources are missed or fit inaccurately once the source size becomes larger than the beam, possibly explaining source count errors in high-resolution surveys. We also investigate the effect of blending, finding that any sources with separations smaller than the beam size are fit as single sources. We show that the use of machine-learning techniques can correctly identify blended sources up to 90 per cent of the time, and prior-driven fitting can lead to a 70 per cent improvement in the number of de-blended sources.

Kerr-AdS analogue of triple point and solid/liquid/gas phase transition

NASA Astrophysics Data System (ADS)

Altamirano, Natacha; Kubizňák, David; Mann, Robert B.; Sherkatghanad, Zeinab

2014-02-01

We study the thermodynamic behavior of multi-spinning d = 6 Kerr-anti de Sitter black holes in the canonical ensemble of fixed angular momenta J1 and J2. We find, dependent on the ratio q = J2/J1, qualitatively different interesting phenomena known from the ‘every day thermodynamics’ of simple substances. For q = 0 the system exhibits recently observed reentrant large/small/large black hole phase transitions, but for 0 < q ≪ 1 we find an analogue of a ‘solid/liquid’ phase transition. Furthermore, for q ∈ (0.00905, 0.0985) the system displays the presence of a large/intermediate/small black hole phase transition with two critical and one triple (or tricritical) points. This behavior is reminiscent of the solid/liquid/gas phase transition except that the coexistence line of small and intermediate black holes does not continue for an arbitrary value of pressure (similar to the solid/liquid coexistence line) but rather terminates at one of the critical points. Finally, for q > 0.0985 we observe the ‘standard liquid/gas behavior’ of the Van der Waals fluid.

Interhemispheric differences and solar cycle effects of the high-latitude ionospheric convection patterns deduced from Cluster EDI observations

NASA Astrophysics Data System (ADS)

Förster, Matthias; Haaland, Stein

2015-04-01

Here, we present a study of ionospheric convection at high latitudes that is based on satellite measurements of the Electron Drift Instrument (EDI) on-board the Cluster satellites, which were obtained over a full solar cycle (2001-2013). The mapped drift measurements are covering both hemispheres and a variety of different solar wind and interplanetary magnetic field (IMF) conditions. The large amount of data allows us to perform more detailed statistical studies. We show that flow patterns and polar cap potentials can differ between the two hemispheres on statistical average for a given IMF orientation. In particular, during southward directed IMF conditions, and thus enhanced energy input from the solar wind, we find that the southern polar cap has a higher cross polar cap potential. We also find persistent north-south asymmetries which cannot be explained by external drivers alone. Much of these asymmetries can probably be explained by significant differences in the strength and configuration of the geomagnetic field between the Northern and Southern Hemisphere. Since the ionosphere is magnetically connected to the magnetosphere, this difference will also be reflected in the magnetosphere in the form of different feedback from the two hemispheres. Consequently, local ionospheric conditions and the geomagnetic field configuration are important for north-south asymmetries in large regions of geospace. The average convection is higher during periods with high solar activity. Although local ionospheric conditions may play a role, we mainly attribute this to higher geomagnetic activity due to enhanced solar wind - magnetosphere interactions.

Administering Spatial and Cognitive Instruments In-class and On-line: Are These Equivalent?

NASA Astrophysics Data System (ADS)

Williamson, Kenneth C.; Williamson, Vickie M.; Hinze, Scott R.

2017-02-01

Standardized, well-established paper-and-pencil tests, which measure spatial abilities or which measure reasoning abilities, have long been found to be predictive of success in the STEM (science, technology, engineering, and mathematics) fields. Instructors can use these tests for prediction of success and to inform instruction. A comparative administration of spatial visualization and cognitive reasoning tests, between in-class (proctored paper and pencil) and on-line (unproctored Internet) ( N = 457), was used to investigate and to determine whether the differing instrument formats yielded equal measures of spatial ability and reasoning ability in large first-semester general chemistry sections. Although some gender differences were found, findings suggest that some differences across administration formats, but that on-line administration had similar properties of predicting chemistry performance as the in-class version. Therefore, on-line administration is a viable option for instructors to consider especially when dealing with large classes.

Compassion and contamination. Cultural differences in vegetarianism.

PubMed

Ruby, Matthew B; Heine, Steven J; Kamble, Shanmukh; Cheng, Tessa K; Waddar, Mahadevi

2013-12-01

A growing body of research has shown that Western vegetarians report more concern for animal welfare and environmental sustainability, and endorse more liberal values than do Western omnivores. However, despite the prevalence of Indian vegetarianism, its psychological associations and underpinnings remain largely unexamined. In Study 1, we find that Euro-American vegetarians are more concerned than omnivores with the impact of their daily food choices on the environment and animal welfare, show more concern for general animal welfare, and endorse universalistic values more, yet among Indian participants, these differences are not significant. In Study 2, we show that Indian vegetarians more strongly endorse the belief that eating meat is polluting, and show a heightened concern for the conservative ethics of Purity, Authority, and Ingroup relative to their omnivorous peers, whereas these differences are largely absent among Euro-Canadians and Euro-Americans. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fast adaptive flat-histogram ensemble to enhance the sampling in large systems

NASA Astrophysics Data System (ADS)

Xu, Shun; Zhou, Xin; Jiang, Yi; Wang, YanTing

2015-09-01

An efficient novel algorithm was developed to estimate the Density of States (DOS) for large systems by calculating the ensemble means of an extensive physical variable, such as the potential energy, U, in generalized canonical ensembles to interpolate the interior reverse temperature curve , where S( U) is the logarithm of the DOS. This curve is computed with different accuracies in different energy regions to capture the dependence of the reverse temperature on U without setting prior grid in the U space. By combining with a U-compression transformation, we decrease the computational complexity from O( N 3/2) in the normal Wang Landau type method to O( N 1/2) in the current algorithm, as the degrees of freedom of system N. The efficiency of the algorithm is demonstrated by applying to Lennard Jones fluids with various N, along with its ability to find different macroscopic states, including metastable states.

Hydrophobic and Hydrophilic Au and Ag Nanoparticles. Breakthroughs and Perspectives

PubMed Central

2017-01-01

This review provides a broad look on the recent investigations on the synthesis, characterization and physico-chemical properties of noble metal nanoparticles, mainly gold and silver nanoparticles, stabilized with ligands of different chemical nature. A comprehensive review of the available literature in this field may be far too large and only some selected representative examples will be reported here, together with some recent achievements from our group, that will be discussed in more detail. Many efforts in finding synthetic routes have been performed so far to achieve metal nanoparticles with well-defined size, morphology and stability in different environments, to match the large variety of applications that can be foreseen for these materials. In particular, the synthesis and stabilization of gold and silver nanoparticles together with their properties in different emerging fields of nanomedicine, optics and sensors are reviewed and briefly commented. PMID:29280980

Pseudorapidity dependence of the anisotropic flow of charged particles in Pb-Pb collisions at √{sNN} = 2.76 TeV

NASA Astrophysics Data System (ADS)

Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; Aiola, S.; Akindinov, A.; Alam, S. N.; Albuquerque, D. S. D.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Almaraz, J. R. M.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Arnaldi, R.; Arnold, O. W.; Arsene, I. C.; Arslandok, M.; Audurier, B.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Balasubramanian, S.; Baldisseri, A.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Barth, K.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Beltran, L. G. E.; Belyaev, V.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biro, G.; Biswas, R.; Biswas, S.; Bjelogrlic, S.; Blair, J. T.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Bonora, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botta, E.; Bourjau, C.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Butt, J. B.; Buxton, J. T.; Cabala, J.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Carnesecchi, F.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Ceballos Sanchez, C.; Cepila, J.; Cerello, P.; Cerkala, J.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chauvin, A.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Cho, S.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa Del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crkovska, J.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danisch, M. C.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; de, S.; de Caro, A.; de Cataldo, G.; de Conti, C.; de Cuveland, J.; de Falco, A.; de Gruttola, D.; De Marco, N.; de Pasquale, S.; de Souza, R. D.; Deisting, A.; Deloff, A.; Dénes, E.; Deplano, C.; Dhankher, P.; di Bari, D.; di Mauro, A.; di Nezza, P.; di Ruzza, B.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Drozhzhova, T.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Endress, E.; Engel, H.; Epple, E.; Erazmus, B.; Erdemir, I.; Erhardt, F.; Espagnon, B.; Estienne, M.; Esumi, S.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Feuillard, V. J. G.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Francisco, A.; Frankenfeld, U.; Fronze, G. G.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gajdosova, K.; Gallio, M.; Galvan, C. D.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Gauger, E. F.; Germain, M.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Goméz Coral, D. M.; Gomez Ramirez, A.; Gonzalez, A. S.; Gonzalez, V.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Grachov, O. A.; Graczykowski, L. K.; Graham, K. L.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Gronefeld, J. M.; Grosse-Oetringhaus, J. F.; Grosso, R.; Gruber, L.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hamon, J. C.; Hansen, A.; Harris, J. W.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Hellbär, E.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Hess, B. A.; Hetland, K. F.; Hillemanns, H.; Hippolyte, B.; Horak, D.; Hosokawa, R.; Hristov, P.; Hughes, C.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Inaba, M.; Incani, E.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacak, B.; Jacazio, N.; Jacobs, P. M.; Jadhav, M. B.; Jadlovska, S.; Jadlovsky, J.; Jahnke, C.; Jakubowska, M. J.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karayan, L.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Mohisin Khan, M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, D. W.; Kim, D. J.; Kim, D.; Kim, H.; Kim, J. S.; Kim, J.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Klewin, S.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobdaj, C.; Kofarago, M.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kopcik, M.; Kour, M.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Koyithatta Meethaleveedu, G.; Králik, I.; Kravčáková, A.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kuhn, C.; Kuijer, P. G.; Kumar, A.; Kumar, J.; Kumar, L.; Kumar, S.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Ladron de Guevara, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lapidus, K.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, S.; Lehas, F.; Lehner, S.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; León Vargas, H.; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Luettig, P.; Lunardon, M.; Luparello, G.; Lupi, M.; Lutz, T. H.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manko, V.; Manso, F.; Manzari, V.; Mao, Y.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Martin Blanco, J.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Mastroserio, A.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; McDonald, D.; Meddi, F.; Melikyan, Y.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Mhlanga, S.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Mischke, A.; Mishra, A. N.; Miśkowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montaño Zetina, L.; Montes, E.; Moreira de Godoy, D. A.; Moreno, L. A. P.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Mulligan, J. D.; Munhoz, M. G.; Münning, K.; Munzer, R. H.; Murakami, H.; Murray, S.; Musa, L.; Musinsky, J.; Naik, B.; Nair, R.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Natal da Luz, H.; Nattrass, C.; Navarro, S. R.; Nayak, K.; Nayak, R.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Negrao de Oliveira, R. A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Noris, J. C. C.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Oleniacz, J.; Oliveira da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Orava, R.; Oravec, M.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, D.; Pagano, P.; Paić, G.; Pal, S. K.; Pan, J.; Pandey, A. K.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Patra, R. N.; Paul, B.; Pei, H.; Peitzmann, T.; Pereira da Costa, H.; Peresunko, D.; Perez Lezama, E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pimentel, L. O. D. L.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Płoskoń, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Poppenborg, H.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rami, F.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Read, K. F.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rocco, E.; Rodríguez Cahuantzi, M.; Rodriguez Manso, A.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Saarinen, S.; Sadhu, S.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Šándor, L.; Sandoval, A.; Sano, M.; Sarkar, D.; Sarkar, N.; Sarma, P.; Scapparone, E.; Scarlassara, F.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schmidt, M.; Schuchmann, S.; Schukraft, J.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Šefčík, M.; Seger, J. E.; Sekiguchi, Y.; Sekihata, D.; Selyuzhenkov, I.; Senosi, K.; Senyukov, S.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shahzad, M. I.; Shangaraev, A.; Sharma, A.; Sharma, M.; Sharma, M.; Sharma, N.; Sheikh, A. I.; Shigaki, K.; Shou, Q.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singhal, V.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; Sozzi, F.; Spiriti, E.; Sputowska, I.; Spyropoulou-Stassinaki, M.; Stachel, J.; Stan, I.; Stankus, P.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Suljic, M.; Sultanov, R.; Šumbera, M.; Sumowidagdo, S.; Szabo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Tabassam, U.; Takahashi, J.; Tambave, G. J.; Tanaka, N.; Tarhini, M.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thakur, D.; Thomas, D.; Tieulent, R.; Tikhonov, A.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trombetta, G.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vala, M.; Valencia Palomo, L.; Vallero, S.; van der Maarel, J.; van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vázquez Doce, O.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Verweij, M.; Vickovic, L.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Villatoro Tello, A.; Vinogradov, A.; Vinogradov, L.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Watanabe, D.; Watanabe, Y.; Weber, M.; Weber, S. G.; Weiser, D. F.; Wessels, J. P.; Westerhoff, U.; Whitehead, A. M.; Wiechula, J.; Wikne, J.; Wilk, G.; Wilkinson, J.; Willems, G. A.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yang, P.; Yano, S.; Yasin, Z.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yoon, J. H.; Yurchenko, V.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zardoshti, N.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhang, C.; Zhang, Z.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.; Alice Collaboration

2016-11-01

We present measurements of the elliptic (v2), triangular (v3) and quadrangular (v4) anisotropic azimuthal flow over a wide range of pseudorapidities (- 3.5 < η < 5). The measurements are performed with Pb-Pb collisions at √{sNN} = 2.76 TeV using the ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are obtained using two- and four-particle correlations from nine different centrality intervals covering central to peripheral collisions. We find that the shape of vn (η) is largely independent of centrality for the flow harmonics n = 2- 4, however the higher harmonics fall off more steeply with increasing | η |. We assess the validity of extended longitudinal scaling of v2 by comparing to lower energy measurements, and find that the higher harmonic flow coefficients are proportional to the charged particle densities at larger pseudorapidities. Finally, we compare our measurements to both hydrodynamical and transport models, and find they both have challenges when it comes to describing our data.

Pseudorapidity dependence of the anisotropic flow of charged particles in Pb–Pb collisions at s NN = 2.76  TeV

DOE PAGES

Adam, J.; Adamová, D.; Aggarwal, M. M.; ...

2016-07-11

We present measurements of the elliptic (v 2 ), triangular (v 3 ) and quadrangular (v 4 ) anisotropic azimuthal flow over a wide range of pseudorapidities (-3.5 < η < 5). The measurements are performed with Pb–Pb collisions at √s NN =2.76 TeV using the ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are obtained using two- and four-particle correlations from nine different centrality intervals covering central to peripheral collisions. We find that the shape of v n(η) is largely independent of centrality for the flow harmonics n=2–4, however the higher harmonics fall off more steeplymore » with increasing |η|. We assess the validity of extended longitudinal scaling of v₂ by comparing to lower energy measurements, and find that the higher harmonic flow coefficients are proportional to the charged particle densities at larger pseudorapidities. Finally, we compare our measurements to both hydrodynamical and transport models, and find they both have challenges when it comes to describing our data.« less

The self-efficacy-interest relationship and RIASEC type: Which is figure and which is ground? Comment on Armstrong and Vogel (2009).

PubMed

Lent, Robert W; Sheu, Hung-Bin; Brown, Steven D

2010-04-01

Armstrong and Vogel (2009) proposed that the differences between self-efficacy and interests are a matter of measurement artifact rather than substance. In tests of this hypothesis, they conceived of self-efficacy and interest as observed indicators of larger RIASEC (Realistic, Investigative, Artistic, Social, Enterprising, and Conventional) types and as response method factors. We revisit the authors' theoretical assumptions, measurement procedures, analyses, and interpretation of findings. When viewing this study in the context of the larger literature, we find ample support for the construal of self-efficacy and interests as distinct but related constructs. In addition, we examine the authors' reanalysis of earlier longitudinal findings, reaching different conclusions than they did about the nature of the temporal relations among the social cognitive variables. Ultimately, whether one wishes to highlight or minimize the differences between interest and self-efficacy may largely depend on whether one's purpose is explanation (e.g., how do people make career-relevant choices?) or classification (e.g., which RIASEC type does a person most resemble?). PsycINFO Database Record (c) 2010 APA, all rights reserved.

Brain size is correlated with endangerment status in mammals.

PubMed

Abelson, Eric S

2016-02-24

Increases in relative encephalization (RE), brain size after controlling for body size, comes at a great metabolic cost and is correlated with a host of cognitive traits, from the ability to count objects to higher rates of innovation. Despite many studies examining the implications and trade-offs accompanying increased RE, the relationship between mammalian extinction risk and RE is unknown. I examine whether mammals with larger levels of RE are more or less likely to be at risk of endangerment than less-encephalized species. I find that extant species with large levels of encephalization are at greater risk of endangerment, with this effect being strongest in species with small body sizes. These results suggest that RE could be a valuable asset in estimating extinction vulnerability. Additionally, these findings suggest that the cost-benefit trade-off of RE is different in large-bodied species when compared with small-bodied species. © 2016 The Author(s).

Predictors of Prosocial Behavior among Chinese High School Students in Hong Kong

PubMed Central

Siu, Andrew M. H.; Shek, Daniel T. L.; Lai, Frank H. Y.

2012-01-01

This study examined the correlates and predictors of prosocial behavior among Chinese adolescents in Hong Kong. A sample of 518 high school students responded to a questionnaire containing measures of antisocial and prosocial behavior, prosocial norms, pragmatic values, moral reasoning, and empathy. Preliminary analyses showed that there were gender differences in some of the measures. While correlation analyses showed that parental education, prosocial norms, pragmatic values, moral reasoning, and empathy were related to prosocial behavior, regression analyses showed that prosocial norms, pragmatic values, and empathy dimensions (personal distress and empathy) were key predictors of it. The findings are largely consistent with theoretical predictions and previous research findings, other than the negative relationship between personal distress and prosocial behavior. The study also underscores the importance of values and norms in predicting prosocial behavior, which has been largely neglected in previous studies. PMID:22919326

Decomposing the effect of crime on population changes.

PubMed

Foote, Andrew

2015-04-01

This article estimates the effect of crime on migration rates for counties in U.S. metropolitan areas and makes three contributions to the literature. First, I use administrative data on migration flows between counties, which gives me more precise estimates of population changes than data used in previous studies. Second, I am able to decompose net population changes into gross migration flows in order to identify how individuals respond to crime rate changes. Finally, I include county-level trends so that my identification comes from shocks away from the trend. I find effects that are one-fiftieth the size of the most prominent estimate in the literature; and although the long-run effects are somewhat larger, they are still only approximately one-twentieth as large. I also find that responses to crime rates differ by subgroups, and that increases in crime cause white households to leave the county, with effects almost 10 times as large as for black households.

Correlations of heavy quarks produced at the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Younus, Mohammed; Jamil, Umme; Srivastava, Dinesh K.

2012-02-01

We study the correlations of heavy quarks produced in relativistic heavy-ion collisions and find them to be quite sensitive to the effects of the medium and the production mechanisms. In order to put this on a quantitative footing, as a first step, we analyze the azimuthal, transverse momentum, and rapidity correlations of heavy quark-antiquark (Q\\overline{Q}) pairs in pp collisions at {O}(α3s). This sets the stage for the identification and study of medium modification of similar correlations in the relativistic collision of heavy nuclei at the Large Hadron Collider. Next we study the additional production of charm quarks in heavy ion collisions due to multiple scatterings, namely jet-jet collisions, jet-thermal collisions, and thermal interactions. We find that these give rise to azimuthal correlations which are quite different from those arising from the prompt initial production at leading order and at next to leading order. Communicated by Professor Steffen Bass.

Generalized polarizabilities of the nucleon in baryon chiral perturbation theory

NASA Astrophysics Data System (ADS)

Lensky, Vadim; Pascalutsa, Vladimir; Vanderhaeghen, Marc

2017-02-01

The nucleon generalized polarizabilities (GPs), probed in virtual Compton scattering (VCS), describe the spatial distribution of the polarization density in a nucleon. They are accessed experimentally via the process of electron-proton bremsstrahlung (ep→ epγ ) at electron-beam facilities, such as MIT-Bates, CEBAF (Jefferson Lab), and MAMI (Mainz). We present the calculation of the nucleon GPs and VCS observables at next-to-leading order in baryon chiral perturbation theory (Bχ PT), and confront the results with the empirical information. At this order our results are predictions, in the sense that all the parameters are well known from elsewhere. Within the relatively large uncertainties of our calculation we find good agreement with the experimental observations of VCS and the empirical extractions of the GPs. We find large discrepancies with previous chiral calculations - all done in heavy-baryon χ PT (HBχ PT) - and discuss the differences between Bχ PT and HBχ PT responsible for these discrepancies.

Capacity market design and renewable energy: Performance incentives, qualifying capacity, and demand curves

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

Byers, Conleigh; Levin, Todd; Botterud, Audun

A review of capacity markets in the United States in the context of increasing levels of variable renewable energy finds substantial differences with respect to incentives for operational performance, methods to calculate qualifying capacity for variable renewable energy and energy storage, and demand curves for capacity. The review also reveals large differences in historical capacity market clearing prices. The authors conclude that electricity market design must continue to evolve to achieve cost-effective policies for resource adequacy.

Science and Engineering Ph.D. Students' Career Outcomes, by Gender.

PubMed

Conti, Annamaria; Visentin, Fabiana

2015-01-01

We examine differences in the careers of men and women Ph.D.s from two major European universities. Having performed regression analysis, we find that women are more likely than men to be employed in public administration when the alternatives are either academia or industry. Between the latter two alternatives, women are more likely to be employed in academia. These gender differences persist after accounting for Ph.D.s' and their supervisors' characteristics. Gender gaps are smaller for Ph.D.s with large research outputs and for those who conducted applied research. Restricting the analysis to Ph.D.s who pursued postdoc training, women are less likely than men to be employed in highly ranked universities, even after controlling for their research outputs. Finally, we find gender differences in Ph.D.s' appointment to professorship, which are explained by the Ph.D.s' publication output and the quality of their postdoc training.

Thermally driven magnetic precession in spin valves

NASA Astrophysics Data System (ADS)

Luc, David; Waintal, Xavier

2014-10-01

We investigate the angular dependence of the spin torque generated when applying a temperature difference across a spin valve. Our study shows the presence of a nontrivial fixed point in this angular dependence. This fixed point opens the possibility for a temperature gradient to stabilize radio frequency oscillations without the need for an external magnetic field. This so-called "wavy" behavior can already be found upon applying a voltage difference across a spin valve but we find that this effect is much more pronounced with a temperature difference. We find that a spin asymmetry of the Seebeck coefficient of the order of 20 μ VK -1 should be large enough for a temperature gradient of a few degrees to trigger the radio-frequency oscillations. Our semiclassical theory is fully parametrized with experimentally measured(able) parameters and allows one to quantitatively predict the amplitude of the torque.

Temporal patterns of scientific information-seeking on Google and Wikipedia.

PubMed

Segev, Elad; Sharon, Aviv J

2017-11-01

In response to the news coverage of scientific events and to science education, people increasingly go online to get more information. This study investigates how patterns of science and technology information-seeking on Google and Wikipedia change over time, in ways that differ between "ad hoc" terms that correspond to news coverage and "cyclic" terms that correspond to the academic period. Findings show that the science and technology activity in Google and Wikipedia was significantly associated with ad hoc and cyclic patterns. While the peak activity in Google and Wikipedia largely overlapped for ad hoc terms, it mismatched for cyclic terms. The findings indicate the importance of external cues such as news media and education, and also of the online engagement process, and particularly the crucial but different role played by Google and Wikipedia in gaining science and technology knowledge. Educators and policy makers could benefit from taking into account those different patterns.

Musical Preferences Predict Personality: Evidence From Active Listening and Facebook Likes.

PubMed

Nave, Gideon; Minxha, Juri; Greenberg, David M; Kosinski, Michal; Stillwell, David; Rentfrow, Jason

2018-03-01

Research over the past decade has shown that various personality traits are communicated through musical preferences. One limitation of that research is external validity, as most studies have assessed individual differences in musical preferences using self-reports of music-genre preferences. Are personality traits communicated through behavioral manifestations of musical preferences? We addressed this question in two large-scale online studies with demographically diverse populations. Study 1 ( N = 22,252) shows that reactions to unfamiliar musical excerpts predicted individual differences in personality-most notably, openness and extraversion-above and beyond demographic characteristics. Moreover, these personality traits were differentially associated with particular music-preference dimensions. The results from Study 2 ( N = 21,929) replicated and extended these findings by showing that an active measure of naturally occurring behavior, Facebook Likes for musical artists, also predicted individual differences in personality. In general, our findings establish the robustness and external validity of the links between musical preferences and personality.

A study for testing the Kerr metric with AGN iron line eclipses

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

Cárdenas-Avendaño, Alejandro; Jiang, Jiachen; Bambi, Cosimo, E-mail: alejandro.cardenasa@konradlorenz.edu.co, E-mail: jcjiang12@fudan.edu.cn, E-mail: bambi@fudan.edu.cn

2016-04-01

Recently, two of us have studied iron line reverberation mapping to test black hole candidates, showing that the time information in reverberation mapping can better constrain the Kerr metric than the time-integrated approach. Motivated by this finding, here we explore the constraining power of another time-dependent measurement: an AGN iron line eclipse. An obscuring cloud passes between the AGN and the distant observer, covering different parts of the accretion disk at different times. Similar to the reverberation measurement, an eclipse might help to better identify the relativistic effects affecting the X-ray photons. However, this is not what we find. Inmore » our study, we employ the Johannsen-Psaltis parametrisation, but we argue that our conclusions hold in a large class of non-Kerr metrics. We explain our results pointing out an important difference between reverberation and eclipse measurements.« less

Science and Engineering Ph.D. Students’ Career Outcomes, by Gender

PubMed Central

2015-01-01

We examine differences in the careers of men and women Ph.D.s from two major European universities. Having performed regression analysis, we find that women are more likely than men to be employed in public administration when the alternatives are either academia or industry. Between the latter two alternatives, women are more likely to be employed in academia. These gender differences persist after accounting for Ph.D.s’ and their supervisors’ characteristics. Gender gaps are smaller for Ph.D.s with large research outputs and for those who conducted applied research. Restricting the analysis to Ph.D.s who pursued postdoc training, women are less likely than men to be employed in highly ranked universities, even after controlling for their research outputs. Finally, we find gender differences in Ph.D.s’ appointment to professorship, which are explained by the Ph.D.s’ publication output and the quality of their postdoc training. PMID:26244797

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

Lim, Dongwook; Han, Sang-Il; Lee, Young-Wook

There is increasing evidence for the presence of multiple red giant branches (RGBs) in the color-magnitude diagrams of massive globular clusters (GCs). In order to investigate the origin of this split on the RGB, we have performed new narrow-band Ca photometry and low-resolution spectroscopy for M22, NGC 1851, and NGC 288. We find significant differences (more than 4σ) in calcium abundance from the spectroscopic HK' index for M22 and NGC 1851. We also find more than 8σ differences in CN-band strength between the Ca-strong and Ca-weak subpopulations for these GCs. For NGC 288, however, a large difference is detected onlymore » in the CN strength. The calcium abundances of RGB stars in this GC are identical to within the errors. This is consistent with the conclusion from our new Ca photometry where the RGB splits are confirmed in M22 and NGC 1851, but not in NGC 288. We also find interesting differences in the CN-CH correlations among these GCs. While CN and CH are anti-correlated in NGC 288, they show a positive correlation in M22. NGC 1851, however, shows no difference in CH between the two groups of stars with different CN strengths. We suggest that all of these systematic differences would be best explained by how strongly Type II supernovae enrichment has contributed to the chemical evolution of these GCs.« less

Convergence and approximate calculation of average degree under different network sizes for decreasing random birth-and-death networks

NASA Astrophysics Data System (ADS)

Long, Yin; Zhang, Xiao-Jun; Wang, Kui

2018-05-01

In this paper, convergence and approximate calculation of average degree under different network sizes for decreasing random birth-and-death networks (RBDNs) are studied. First, we find and demonstrate that the average degree is convergent in the form of power law. Meanwhile, we discover that the ratios of the back items to front items of convergent reminder are independent of network link number for large network size, and we theoretically prove that the limit of the ratio is a constant. Moreover, since it is difficult to calculate the analytical solution of the average degree for large network sizes, we adopt numerical method to obtain approximate expression of the average degree to approximate its analytical solution. Finally, simulations are presented to verify our theoretical results.

Integration of epigenetic game theory and developmental principles. Reply to comments on ;Epigenetic game theory: How to compute the epigenetic control of maternal-to-zygotic transition;

NASA Astrophysics Data System (ADS)

Wang, Qian; Gosik, Kirk; Xing, Sujuan; Jiang, Libo; Sun, Lidan; Chinchilli, Vernon M.; Wu, Rongling

2017-03-01

In its recent issue, Science published breaking global health news, regarding the discovery of pronounced differences of fetal growth rate between countries, even if the mothers of babies were equally given the optimal circumstances [1]. This discovery by a large team of obstetric and gynecological researchers from multiple countries [2] changes a previous view from a large project called INTERGROWTH-21st, which claims that growth trajectories of unborn babies follow a similar form between countries [3]. This new finding provides evidence of the important role of genetic and epigenetic variants (differing between ethnic groups) in determining fetal growth, a process that is generally believed to be affected predominantly by nutrition and socioeconomic status [4].

Reflections on the challenges of understanding racial, cultural and sexual differences in couple relationship research

PubMed Central

Gabb, Jacqui; Singh, Reenee

2015-01-01

In the field of systemic psychotherapy there has been much recent interest in the areas of culture and reflexivity, and in working with couples. In this article we reflect on the process of conducting research in these areas. Drawing on findings from a large, national, empirical mixed-methods study on long-term relationships, we use two examples from the data to illustrate the complexity of researching across racial, cultural and sexual differences, in terms of research design and sampling, fieldwork and research practice, and making sense of multidimensional data. We point to findings that suggest that notions of coupledom are culturally constructed and thus challenge straightforward ideas of the procreative, sexually active couple dyad, separate from intergenerational extended families. The clinical significance of the findings for both lesbian, gay, bisexual or queer and culturally diverse couples and families are discussed. Practitioner points Cultural or racial matching is not a sufficient condition for engagement and empathy with couples and families. Critical reflexivity about similarity and difference is essential in cross-cultural systemic practice. ‘The couple’ and its distance from the extended family may be defined differently in different cultures. One research tool used in this project, the emotion map, appears to have utility in clinical practice with couples and families. PMID:25820766

The different neighbours around Type-1 and Type-2 active galactic nuclei

NASA Astrophysics Data System (ADS)

Villarroel, Beatriz; Korn, Andreas J.

2014-06-01

One of the most intriguing open issues in galaxy evolution is the structure and evolution of active galactic nuclei (AGN) that emit intense light believed to come from an accretion disk near a super massive black hole. To understand the zoo of different AGN classes, it has been suggested that all AGN are the same type of object viewed from different angles. This model--called AGN unification--has been successful in predicting, for example, the existence of hidden broad optical lines in the spectrum of many narrow-line AGN. But this model is not unchallenged and it is debatable whether more than viewing angle separates the so-called Type-1 and Type-2 AGN. Here we report the first large-scale study that finds strong differences in the galaxy neighbours to Type-1 and Type-2 AGN with data from the Sloan Digital Sky Survey (SDSS; ref. ) Data Release 7 (DR7; ref. ) and Galaxy Zoo. We find strong differences in the colour and AGN activity of the neighbours to Type-1 and Type-2 AGN and in how the fraction of AGN residing in spiral hosts changes depending on the presence or not of a neighbour. These findings suggest that an evolutionary link between the two major AGN types might exist.

Practice settings and dentists' job satisfaction.

PubMed

Lo Sasso, Anthony T; Starkel, Rebecca L; Warren, Matthew N; Guay, Albert H; Vujicic, Marko

2015-08-01

The nature and organization of dental practice is changing. The aim of this study was to explore how job satisfaction among dentists is associated with dental practice setting. A survey measured satisfaction with income, benefits, hours worked, clinical autonomy, work-life balance, emotional exhaustion, and overall satisfaction among dentists working in large group, small group, and solo practice settings; 2,171 dentists responded. The authors used logistic regression to measure differences in reported levels of satisfaction across practice settings. Dentists working in small group settings reported the most satisfaction overall. Dentists working in large group settings reported more satisfaction with income and benefits than dentists in solo practice, as well as having the least stress. Findings suggest possible advantages and disadvantages of working in different types of practice settings. Dentists working in different practice settings reported differences in satisfaction. These results may help dentists decide which practice setting is best for them. Copyright © 2015 American Dental Association. Published by Elsevier Inc. All rights reserved.

Diagnosing prosopagnosia in East Asian individuals: Norms for the Cambridge Face Memory Test-Chinese.

PubMed

McKone, Elinor; Wan, Lulu; Robbins, Rachel; Crookes, Kate; Liu, Jia

2017-07-01

The Cambridge Face Memory Test (CFMT) is widely accepted as providing a valid and reliable tool in diagnosing prosopagnosia (inability to recognize people's faces). Previously, large-sample norms have been available only for Caucasian-face versions, suitable for diagnosis in Caucasian observers. These are invalid for observers of different races due to potentially severe other-race effects. Here, we provide large-sample norms (N = 306) for East Asian observers on an Asian-face version (CFMT-Chinese). We also demonstrate methodological suitability of the CFMT-Chinese for prosopagnosia diagnosis (high internal reliability, approximately normal distribution, norm-score range sufficiently far above chance). Additional findings were a female advantage on mean performance, plus a difference between participants living in the East (China) or the West (international students, second-generation children of immigrants), which we suggest might reflect personality differences associated with willingness to emigrate. Finally, we demonstrate suitability of the CFMT-Chinese for individual differences studies that use correlations within the normal range.

Large Deviations in Weakly Interacting Boundary Driven Lattice Gases

NASA Astrophysics Data System (ADS)

van Wijland, Frédéric; Rácz, Zoltán

2005-01-01

One-dimensional, boundary-driven lattice gases with local interactions are studied in the weakly interacting limit. The density profiles and the correlation functions are calculated to first order in the interaction strength for zero-range and short-range processes differing only in the specifics of the detailed-balance dynamics. Furthermore, the effective free-energy (large-deviation function) and the integrated current distribution are also found to this order. From the former, we find that the boundary drive generates long-range correlations only for the short-range dynamics while the latter provides support to an additivity principle recently proposed by Bodineau and Derrida.

The Canadian Natural Health Products (NHP) Regulations: Industry Compliance Motivations

PubMed Central

Laeeque, Hina; Kachan, Natasha; Cohen, Jillian Clare; D'Cruz, Joseph

2007-01-01

This qualitative study explores corporations' motivations to comply with new natural health products (NHP) Regulations in Canada. Interviews were conducted with representatives from 20 Canadian NHP companies. Findings show that the rationale for compliance differs for large compared to small and medium-sized enterprises (SMEs). Large firms are motivated to comply with the regulations because of the deterrent fear of negative media coverage, social motivations, ability to comply and maintaining a competitive market advantage. In contrast, SMEs are motivated to comply due to the deterrent fear of legal prosecution and a sense of duty. PMID:17549245

The Canadian Natural Health Products (NHP) regulations: industry compliance motivations.

PubMed

Laeeque, Hina; Boon, Heather; Kachan, Natasha; Cohen, Jillian Clare; D'Cruz, Joseph

2007-06-01

This qualitative study explores corporations' motivations to comply with new natural health products (NHP) Regulations in Canada. Interviews were conducted with representatives from 20 Canadian NHP companies. Findings show that the rationale for compliance differs for large compared to small and medium-sized enterprises (SMEs). Large firms are motivated to comply with the regulations because of the deterrent fear of negative media coverage, social motivations, ability to comply and maintaining a competitive market advantage. In contrast, SMEs are motivated to comply due to the deterrent fear of legal prosecution and a sense of duty.

Comparative brain transcriptomic analyses of scouting across distinct behavioural and ecological contexts in honeybees

PubMed Central

Liang, Zhengzheng S.; Mattila, Heather R.; Rodriguez-Zas, Sandra L.; Southey, Bruce R.; Seeley, Thomas D.; Robinson, Gene E.

2014-01-01

Individual differences in behaviour are often consistent across time and contexts, but it is not clear whether such consistency is reflected at the molecular level. We explored this issue by studying scouting in honeybees in two different behavioural and ecological contexts: finding new sources of floral food resources and finding a new nest site. Brain gene expression profiles in food-source and nest-site scouts showed a significant overlap, despite large expression differences associated with the two different contexts. Class prediction and ‘leave-one-out’ cross-validation analyses revealed that a bee's role as a scout in either context could be predicted with 92.5% success using 89 genes at minimum. We also found that genes related to four neurotransmitter systems were part of a shared brain molecular signature in both types of scouts, and the two types of scouts were more similar for genes related to glutamate and GABA than catecholamine or acetylcholine signalling. These results indicate that consistent behavioural tendencies across different ecological contexts involve a mixture of similarities and differences in brain gene expression. PMID:25355476

Cultural variation is part of human nature : Literary universals, context-sensitivity, and "shakespeare in the bush".

PubMed

Sugiyama, Michelle Scalise

2003-12-01

In 1966, Laura Bohannan wrote her classic essay challenging the supposition that great literary works speak to universal human concerns and conditions and, by extension, that human nature is the same everywhere. Her evidence: the Tiv of West Africa interpret Hamlet differently from Westerners. While Bohannan's essay implies that cognitive universality and cultural variation are mutually exclusive phenomena, adaptationist theory suggests otherwise. Adaptive problems ("the human condition") and cognitive adaptations ("human nature") are constant across cultures. What differs between cultures is habitat: owing to environmental variation, the means and information relevant to solving adaptive problems differ from place to place. Thus, we find differences between cultures not because human minds differ in design but largely because human habitats differ in resources and history. On this view, we would expect world literature to express both human universals and cultural particularities. Specifically, we should expect to find literary universality at the macro level (e.g., adaptive problems, cognitive adaptations) and literary variation at the micro level (e.g., local solutions to adaptive problems).

Origins of spatial, temporal and numerical cognition: Insights from comparative psychology.

PubMed

Haun, Daniel B M; Jordan, Fiona M; Vallortigara, Giorgio; Clayton, Nicky S

2010-12-01

Contemporary comparative cognition has a large repertoire of animal models and methods, with concurrent theoretical advances that are providing initial answers to crucial questions about human cognition. What cognitive traits are uniquely human? What are the species-typical inherited predispositions of the human mind? What is the human mind capable of without certain types of specific experiences with the surrounding environment? Here, we review recent findings from the domains of space, time and number cognition. These findings are produced using different comparative methodologies relying on different animal species, namely birds and non-human great apes. The study of these species not only reveals the range of cognitive abilities across vertebrates, but also increases our understanding of human cognition in crucial ways. Copyright © 2010 Elsevier Ltd. All rights reserved.

Education, Labor Markets, and the Retreat from Marriage

PubMed Central

Harknett, Kristen; Kuperberg, Arielle

2012-01-01

Using data from the Fragile Families and Child Wellbeing study and Current Population Surveys, we find that labor market conditions play a large role in explaining the positive relationship between educational attainment and marriage. Our results suggest that if low-educated parents faced the same (stronger) labor market conditions as their more-educated counterparts, then differences in marriage by education would narrow considerably. Better labor markets are positively related to marriage for fathers at all educational levels. In contrast, better labor markets are positively related to marriage for less-educated mothers but not their more-educated counterparts. We discuss the implications of our findings for theories about women’s earning power and marriage, the current economic recession, and future studies of differences in family structure across education groups. PMID:23152645

EXAMINING TATOOINE: ATMOSPHERIC MODELS OF NEPTUNE-LIKE CIRCUMBINARY PLANETS

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

May, E. M.; Rauscher, E.

2016-08-01

Circumbinary planets experience a time-varying irradiation pattern as they orbit their two host stars. In this work, we present the first detailed study of the atmospheric effects of this irradiation pattern on known and hypothetical gaseous circumbinary planets. Using both a one-dimensional energy balance model (EBM) and a three-dimensional general circulation model (GCM), we look at the temperature differences between circumbinary planets and their equivalent single-star cases in order to determine the nature of the atmospheres of these planets. We find that for circumbinary planets on stable orbits around their host stars, temperature differences are on average no more thanmore » 1.0% in the most extreme cases. Based on detailed modeling with the GCM, we find that these temperature differences are not large enough to excite circulation differences between the two cases. We conclude that gaseous circumbinary planets can be treated as their equivalent single-star case in future atmospheric modeling efforts.« less

Narrow Networks on the Individual Marketplace in 2017.

PubMed

Polski, Daniel; Weiner, Janet; Zhang, Yuehan

2017-09-01

This Issue Brief describes the breadth of physician networks on the ACA marketplaces in 2017. We find that the overall rate of narrow networks is 21%, which is a decline since 2014 (31%) and 2016 (25%). Narrow networks are concentrated in plans sold on state-based marketplaces, at 42%, compared to 10% of plans on federally-facilitated marketplaces. Issuers that have traditionally offered Medicaid coverage have the highest prevalence of narrow network plans at 36%, with regional/local plans and provider-based plans close behind at 27% and 30%. We also find large differences in narrow networks by state and by plan type.

The evolution of the small x gluon TMD

NASA Astrophysics Data System (ADS)

Zhou, Jian

2016-06-01

We study the evolution of the small x gluon transverse momentum dependent (TMD) distribution in the dilute limit. The calculation has been carried out in the Ji-Ma-Yuan scheme using a simple quark target model. As expected, we find that the resulting small x gluon TMD simultaneously satisfies both the Collins-Soper (CS) evolution equation and the Balitsky-Fadin-Kuraev-Lipatov (BFKL) evolution equation. We thus confirmed the earlier finding that the high energy factorization (HEF) and the TMD factorization should be jointly employed to resum the different type large logarithms in a process where three relevant scales are well separated.

Younger and Older Adults’ Associative Memory for Social Information: The Role of Information Importance

PubMed Central

Hargis, Mary B.; Castel, Alan D.

2017-01-01

The ability to associate items in memory is critical for social interactions. Older adults show deficits in remembering associative information, but can sometimes remember high-value information. In two experiments, younger and older participants studied faces, names, and occupations that were of differing social value. There were no age differences in the recall of important information in Experiment 1, but age differences were present for less important information. In Experiment 2, when younger adults’ encoding time was reduced, age differences were largely absent. These findings are considered in light of value-directed strategies when remembering social associative information. PMID:28581330

Pulmonary involvement in rheumatoid arthritis: multidetector computed tomography findings.

PubMed

Yuksekkaya, Ruken; Celikyay, Fatih; Yilmaz, Ayse; Arslan, Sule; Inanir, Ahmet; Inonu, Handan; Deniz, Caglar

2013-12-01

Pulmonary involvement in rheumatoid arthritis (RA) is common and encompasses a large spectrum of disease with different treatment options and prognoses. Therefore, assessment of these patients with multidetector computed tomography (MDCT) is vital. To evaluate the MDCT pulmonary findings of patients with RA and to compare these findings with the clinical status. Chest MDCT scans of 85 patients with RA between 2006-2012 were assessed. One patient with a pulmonary infection was excluded from the study. MDCT findings and distribution of the CT findings were examined, and patients were classified according to the predominant CT pattern. The pulmonary function test (PFT) results and categories, demographic characteristics, and clinical status of some of the patients for whom the results were obtained were evaluated, and the CT findings, PFT results, demographic characteristics, and clinical status were compared. The study group consisted of 20 men (mean age, 58.1 years ± 13.1; range, 15-77 years) and 64 women (mean age, 55.3 years ± 11.5; range, 30-84 years). The most frequent findings were nodules (78.6%) and pleural thickening (48.8%). The most common CT patterns were follicular bronchiolitis (FB) in 28 (33.3%) patients and nodular disease (ND) in 12 (14.3%) others. There was no statistically significant difference between the CT findings and PFT results, and no statistically significant difference was noted in the CT findings between symptomatic and asymptomatic patients. In addition, there were some patients who exhibited no symptoms and/or had abnormal PFT results but had abnormal CT findings. Rheumatoid arthritis is associated with a high frequency of CT findings and CT patterns, with nodules and pleural thickening being the most common CT findings and FB and ND being the most common CT patterns. MDCT identification of patients with RA may be helpful in the evaluation of pulmonary disease, even in patients without symptoms and PFT abnormalities.

Do racial disparities in private transfers help explain the racial wealth gap? New evidence from longitudinal data.

PubMed

McKernan, Signe-Mary; Ratcliffe, Caroline; Simms, Margaret; Zhang, Sisi

2014-06-01

How do private transfers differ by race and ethnicity, and do such differences explain the racial and ethnic disparity in wealth? Using the Panel Study of Income Dynamics, this study examines private transfers by race and ethnicity in the United States and explores a causal relationship between private transfers and wealth. Panel data and a family-level fixed-effect model are used to control for the endogeneity of private transfers. Private transfers in the form of financial support received and given from extended families and friends, as well as large gifts and inheritances, are examined. We find that African Americans and Hispanics (both immigrant and nonimmigrant) receive less in both types of private transfers than whites. Large gifts and inheritances, but not net financial support received, are related to wealth increases for African American and white families. Overall, we estimate that the African American shortfall in large gifts and inheritances accounts for 12 % of the white-black racial wealth gap.

Finding common ground in large carnivore conservation: mapping contending perspectives

USGS Publications Warehouse

Mattson, D.J.; Byrd, K.L.; Rutherford, M.B.; Brown, S.R.; Clark, T.W.

2006-01-01

Reducing current conflict over large carnivore conservation and designing effective strategies that enjoy broad public support depend on a better understanding of the values, beliefs, and demands of those who are involved or affected. We conducted a workshop attended by diverse participants involved in conservation of large carnivores in the northern U.S. Rocky Mountains, and used Q methodology to elucidate participant perspectives regarding "problems" and "solutions". Q methodology employs qualitative and quantitative techniques to reveal the subjectivity in any situation. We identified four general perspectives for both problems and solutions, three of which (Carnivore Advocates, Devolution Advocates, and Process Reformers) were shared by participants across domains. Agency Empathizers (problems) and Economic Pragmatists (solutions) were not clearly linked. Carnivore and Devolution Advocates expressed diametrically opposed perspectives that legitimized different sources of policy-relevant information ("science" for Carnivore Advocates and "local knowledge" for Devolution Advocates). Despite differences, we identified potential common ground focused on respectful, persuasive, and creative processes that would build understanding and tolerance. ?? 2006 Elsevier Ltd. All rights reserved.

Monitoring the process of pulmonary melanoma metastasis using large area and label-free nonlinear optical microscopy

NASA Astrophysics Data System (ADS)

Hua, Daozhu; Qi, Shuhong; Li, Hui; Zhang, Zhihong; Fu, Ling

2012-06-01

We performed large area nonlinear optical microscopy (NOM) for label-free monitoring of the process of pulmonary melanoma metastasis ex vivo with subcellular resolution in C57BL/6 mice. Multiphoton autofluorescence (MAF) and second harmonic generation (SHG) images of lung tissue are obtained in a volume of ~2.2 mm×2.2 mm×30 μm. Qualitative differences in morphologic features and quantitative measurement of pathological lung tissues at different time points are characterized. We find that combined with morphological features, the quantitative parameters, such as the intensity ratio of MAF and SHG between pathological tissue and normal tissue and the MAF to SHG index versus depth clearly shows the tissue physiological changes during the process of pulmonary melanoma metastasis. Our results demonstrate that large area NOM succeeds in monitoring the process of pulmonary melanoma metastasis, which can provide a powerful tool for the research in tumor pathophysiology and therapy evaluation.

Birth Order, Educational Attainment, and Earnings: An Investigation Using the PSID

ERIC Educational Resources Information Center

Kantarevic, Jasmin; Mechoulan, Stephane

2006-01-01

We examine the implications of being early in the birth order, and whether a pattern exists within large families of falling then rising attainment with respect to birth order. Unlike other studies using U.S. data, we go beyond grade for age and look at racial differences. Drawing from OLS and fixed effects estimations, we find that being…

Diverse users of four urban national forests: participation, preferences, and perceptions

Treesearch

Deborah J. Chavez; David D. Olson

2008-01-01

Diversity at outdoor recreation sites, particularly those near large and diverse urban populations, is occurring across the United States. It is likely that individuals who belong to these changing groups bring a set of values and behaviors to public lands that differ from that of White visitors, and perhaps, land managers. Reported here are findings from studies...

Stress, Social Support, and Outcomes in Two Probability Samples of Homeless Adults

ERIC Educational Resources Information Center

Toro, Paul A.; Tulloch, Elizabeth; Ouellette, Nicole

2008-01-01

This study investigated the main effects of social support measures and their stress-buffering effects in two samples of homeless adults (Ns =249 and 219) obtained in the same large county (surrounding Detroit) at different points in time over an 8-year period (1992-1994 and 2000-2002). The findings suggest that the construct of social support,…

Differences in Persistence Patterns between Life and Physical Science Majors: The Role of Grades, Peers, and Preparation

ERIC Educational Resources Information Center

Ost, Ben

2010-01-01

Using longitudinal administrative data from a large elite research university, this paper separately analyzes the determinants of persistence for life and physical science majors. My results confirm much of the previous research on major persistence in the sciences, but I document that many findings are solely driven by persistence patterns in the…

A Comparative Study on the Effectiveness of English-Medium and Turkish-Medium Accounting Education: Gazi University Case

ERIC Educational Resources Information Center

Zaif, Figen; Karapinar, Aydin; Yangin Eksi, Gonca

2017-01-01

The authors explore the effect of medium of instruction on students' attainments at a large state university in Turkey in the Department of Business Administration. The findings indicate no statistically significant difference in grades of 386 students with respect to medium of instruction. As for entry rankings however, those in the…

Association of Aggressive Behaviours with Psychiatric Disorders, Age, Sex and Degree of Intellectual Disability: A Large-Scale Survey

ERIC Educational Resources Information Center

Tsiouris, J. A.; Kim, S. Y.; Brown, W. T.; Cohen, I. L.

2011-01-01

Background: The link between aggression and mental disorders has been the focus of diverse studies in persons with and without intellectual disabilities (ID). Because of discrepancies in the finding of studies in persons with ID to date, and because of differences in research design, instruments used and the population studied, more research is…

Analysis of the variation in the determination of the shear modulus of the erythrocyte membrane: Effects of the constitutive law and membrane modeling

PubMed Central

Dimitrakopoulos, P.

2013-01-01

Despite research spanning several decades, the exact value of the shear modulus Gs of the erythrocyte membrane is still ambiguous, and a wealth of studies, using measurements based on micropipette aspirations, ektacytometry systems and other flow chambers, and optical tweezers as well as application of several models have found different average values in the range 2–10 µN/m. Our study shows that different methodologies have predicted the correct shear modulus for the specific membrane modeling employed, i.e. the variation in the shear modulus determination results from the specific membrane modeling. Available experimental findings from ektacytometry systems and optical tweezers suggest that the dynamics of the erythrocyte membrane is strain-hardening at both moderate and large deformations. Thus the erythrocyte shear modulus cannot be determined accurately using strain-softening models (such as the neo-Hookean and Evans laws) or strain-softening/strain-hardening models (such as the Yeoh law) which overestimate the erythrocyte shear modulus. According to our analysis, the only available strain-hardening constitutive law, the Skalak et al. law, is able to match well both deformation-shear rate data from ektacytometry and force-extension data from optical tweezers at moderate and large strains, using an average value of the shear modulus of Gs = 2.4–2.75 µN/m, i.e. very close to that found in the linear regime of deformations via force-extension data from optical tweezers, Gs = 2.5±0.4 µN/m. In addition, our analysis suggests that a standard deviation in Gs of 0.4–0.5 µN/m (owing to the inherent differences between erythrocytes within a large population) describes well the findings from optical tweezers at small and large strains as well as from micro-pipette aspirations. PMID:22680508

Object Individuation and Physical Reasoning in Infancy: An Integrative Account

PubMed Central

Baillargeon, Renée; Stavans, Maayan; Wu, Di; Gertner, Yael; Setoh, Peipei; Kittredge, Audrey K.; Bernard, Amélie

2012-01-01

Much of the research on object individuation in infancy has used a task in which two different objects emerge in alternation from behind a large screen, which is then removed to reveal either one or two objects. In their seminal work, Xu and Carey (1996) found that it is typically not until the end of the first year that infants detect a violation when a single object is revealed. Since then, a large number of investigations have modified the standard task in various ways and found that young infants succeed with some but not with other modifications, yielding a complex and unwieldy picture. In this article, we argue that this confusing picture can be better understood by bringing to bear insights from a related subfield of infancy research, physical reasoning. By considering how infants reason about object information within and across physical events, we can make sense of apparently inconsistent findings from different object-individuation tasks. In turn, object-individuation findings deepen our understanding of how physical reasoning develops in infancy. Integrating the insights from physical-reasoning and object-individuation investigations thus enriches both subfields and brings about a clearer account of how infants represent objects and events. PMID:23204946

Survival of pq -superstrings in field theory simulations

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

Lizarraga, Joanes; Urrestilla, Jon, E-mail: joanes.lizarraga@ehu.eus, E-mail: jon.urrestilla@ehu.eus

2016-04-01

We perform large-scale field theoretical simulations in expanding universe to characterize a network of strings that can form composed bound states. The network consists of two copies of Abelian Higgs strings (which we label p and q , respectively) coupled via a potential term to give pq bound states. The simulations are performed using two different kinds of initial conditions: the first one with a network of p - and q -strings, and the second one with a network of q - and pq -strings. This way, we start from two opposite situations: one with no initial pq -strings, andmore » one with a large initial number of pq -strings. We find that in both cases the system scales, and in both cases the system prefers to have a low fraction of pq -strings. This is somewhat surprising in the case for the second type of conditions, showing that the unzipping mechanism is very efficient. We also find hints that both initial conditions tend to asymptote to a common configuration, though we would need a larger dynamical range to confirm it. The average velocities of the different types of strings in the network have also been explored for the first time.« less

Temporal dynamics of online petitions.

PubMed

Böttcher, Lucas; Woolley-Meza, Olivia; Brockmann, Dirk

2017-01-01

Online petitions are an important avenue for direct political action, yet the dynamics that determine when a petition will be successful are not well understood. Here we analyze the temporal characteristics of online-petition signing behavior in order to identify systematic differences between popular petitions, which receive a high volume of signatures, and unpopular ones. We find that, in line with other temporal characterizations of human activity, the signing process is typically non-Poissonian and non-homogeneous in time. However, this process exhibits anomalously high memory for human activity, possibly indicating that synchronized external influence or contagion play and important role. More interestingly, we find clear differences in the characteristics of the inter-event time distributions depending on the total number of signatures that petitions receive, independently of the total duration of the petitions. Specifically, popular petitions that attract a large volume of signatures exhibit more variance in the distribution of inter-event times than unpopular petitions with only a few signatures, which could be considered an indication that the former are more bursty. However, petitions with large signature volume are less bursty according to measures that consider the time ordering of inter-event times. Our results, therefore, emphasize the importance of accounting for time ordering to characterize human activity.

A Campus-Wide Study of STEM Courses: New Perspectives on Teaching Practices and Perceptions

PubMed Central

Vinson, Erin L.; Smith, Jeremy A.; Lewin, Justin D.; Stetzer, MacKenzie R.

2014-01-01

At the University of Maine, middle and high school science, technology, engineering, and mathematics (STEM) teachers observed 51 STEM courses across 13 different departments and collected information on the active-engagement nature of instruction. The results of these observations show that faculty members teaching STEM courses cannot simply be classified into two groups, traditional lecturers or instructors who teach in a highly interactive manner, but instead exhibit a continuum of instructional behaviors between these two classifications. In addition, the observation data reveal that student behavior differs greatly in classes with varied levels of lecture. Although faculty members who teach large-enrollment courses are more likely to lecture, we also identified instructors of several large courses using interactive teaching methods. Observed faculty members were also asked to complete a survey about how often they use specific teaching practices, and we find that faculty members are generally self-aware of their own practices. Taken together, these findings provide comprehensive information about the range of STEM teaching practices at a campus-wide level and how such information can be used to design targeted professional development for faculty. PMID:25452485

When speaker identity is unavoidable: Neural processing of speaker identity cues in natural speech.

PubMed

Tuninetti, Alba; Chládková, Kateřina; Peter, Varghese; Schiller, Niels O; Escudero, Paola

2017-11-01

Speech sound acoustic properties vary largely across speakers and accents. When perceiving speech, adult listeners normally disregard non-linguistic variation caused by speaker or accent differences, in order to comprehend the linguistic message, e.g. to correctly identify a speech sound or a word. Here we tested whether the process of normalizing speaker and accent differences, facilitating the recognition of linguistic information, is found at the level of neural processing, and whether it is modulated by the listeners' native language. In a multi-deviant oddball paradigm, native and nonnative speakers of Dutch were exposed to naturally-produced Dutch vowels varying in speaker, sex, accent, and phoneme identity. Unexpectedly, the analysis of mismatch negativity (MMN) amplitudes elicited by each type of change shows a large degree of early perceptual sensitivity to non-linguistic cues. This finding on perception of naturally-produced stimuli contrasts with previous studies examining the perception of synthetic stimuli wherein adult listeners automatically disregard acoustic cues to speaker identity. The present finding bears relevance to speech normalization theories, suggesting that at an unattended level of processing, listeners are indeed sensitive to changes in fundamental frequency in natural speech tokens. Copyright © 2017 Elsevier Inc. All rights reserved.

Introducing the MCHF/OVRP/SDMP: Multicapacitated/Heterogeneous Fleet/Open Vehicle Routing Problems with Split Deliveries and Multiproducts

PubMed Central

Yilmaz Eroglu, Duygu; Caglar Gencosman, Burcu; Cavdur, Fatih; Ozmutlu, H. Cenk

2014-01-01

In this paper, we analyze a real-world OVRP problem for a production company. Considering real-world constrains, we classify our problem as multicapacitated/heterogeneous fleet/open vehicle routing problem with split deliveries and multiproduct (MCHF/OVRP/SDMP) which is a novel classification of an OVRP. We have developed a mixed integer programming (MIP) model for the problem and generated test problems in different size (10–90 customers) considering real-world parameters. Although MIP is able to find optimal solutions of small size (10 customers) problems, when the number of customers increases, the problem gets harder to solve, and thus MIP could not find optimal solutions for problems that contain more than 10 customers. Moreover, MIP fails to find any feasible solution of large-scale problems (50–90 customers) within time limits (7200 seconds). Therefore, we have developed a genetic algorithm (GA) based solution approach for large-scale problems. The experimental results show that the GA based approach reaches successful solutions with 9.66% gap in 392.8 s on average instead of 7200 s for the problems that contain 10–50 customers. For large-scale problems (50–90 customers), GA reaches feasible solutions of problems within time limits. In conclusion, for the real-world applications, GA is preferable rather than MIP to reach feasible solutions in short time periods. PMID:25045735

Robustness of inflation to inhomogeneous initial conditions

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

Clough, Katy; Lim, Eugene A.; DiNunno, Brandon S.

We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out inmore » the region of the potential that does not support inflation. In the large field case, we confirm previous results that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface is approximately flat. Finally, we consider the large field case with a varying extrinsic curvature K , such that some regions are initially collapsing. We find that this may again lead to local black holes, but overall the spacetime remains inflationary if the spacetime is open, which confirms previous theoretical studies.« less

Exploring Entrainment Patterns of Human Emotion in Social Media

PubMed Central

Luo, Chuan; Zhang, Zhu

2016-01-01

Emotion entrainment, which is generally defined as the synchronous convergence of human emotions, performs many important social functions. However, what the specific mechanisms of emotion entrainment are beyond in-person interactions, and how human emotions evolve under different entrainment patterns in large-scale social communities, are still unknown. In this paper, we aim to examine the massive emotion entrainment patterns and understand the underlying mechanisms in the context of social media. As modeling emotion dynamics on a large scale is often challenging, we elaborate a pragmatic framework to characterize and quantify the entrainment phenomenon. By applying this framework on the datasets from two large-scale social media platforms, we find that the emotions of online users entrain through social networks. We further uncover that online users often form their relations via dual entrainment, while maintain it through single entrainment. Remarkably, the emotions of online users are more convergent in nonreciprocal entrainment. Building on these findings, we develop an entrainment augmented model for emotion prediction. Experimental results suggest that entrainment patterns inform emotion proximity in dyads, and encoding their associations promotes emotion prediction. This work can further help us to understand the underlying dynamic process of large-scale online interactions and make more reasonable decisions regarding emergency situations, epidemic diseases, and political campaigns in cyberspace. PMID:26953692

Exploring Entrainment Patterns of Human Emotion in Social Media.

PubMed

He, Saike; Zheng, Xiaolong; Zeng, Daniel; Luo, Chuan; Zhang, Zhu

2016-01-01

Emotion entrainment, which is generally defined as the synchronous convergence of human emotions, performs many important social functions. However, what the specific mechanisms of emotion entrainment are beyond in-person interactions, and how human emotions evolve under different entrainment patterns in large-scale social communities, are still unknown. In this paper, we aim to examine the massive emotion entrainment patterns and understand the underlying mechanisms in the context of social media. As modeling emotion dynamics on a large scale is often challenging, we elaborate a pragmatic framework to characterize and quantify the entrainment phenomenon. By applying this framework on the datasets from two large-scale social media platforms, we find that the emotions of online users entrain through social networks. We further uncover that online users often form their relations via dual entrainment, while maintain it through single entrainment. Remarkably, the emotions of online users are more convergent in nonreciprocal entrainment. Building on these findings, we develop an entrainment augmented model for emotion prediction. Experimental results suggest that entrainment patterns inform emotion proximity in dyads, and encoding their associations promotes emotion prediction. This work can further help us to understand the underlying dynamic process of large-scale online interactions and make more reasonable decisions regarding emergency situations, epidemic diseases, and political campaigns in cyberspace.

Lifespan changes in attention revisited: Everyday visual search.

PubMed

Brennan, Allison A; Bruderer, Alison J; Liu-Ambrose, Teresa; Handy, Todd C; Enns, James T

2017-06-01

This study compared visual search under everyday conditions among participants across the life span (healthy participants in 4 groups, with average age of 6 years, 8 years, 22 years, and 75 years, and 1 group averaging 73 years with a history of falling). The task involved opening a door and stepping into a room find 1 of 4 everyday objects (apple, golf ball, coffee can, toy penguin) visible on shelves. The background for this study included 2 well-cited laboratory studies that pointed to different cognitive mechanisms underlying each end of the U-shaped pattern of visual search over the life span (Hommel et al., 2004; Trick & Enns, 1998). The results recapitulated some of the main findings of the laboratory study (e.g., a U-shaped function, dissociable factors for maturation and aging), but there were several unique findings. These included large differences in the baseline salience of common objects at different ages, visual eccentricity effects that were unique to aging, and visual field effects that interacted strongly with age. These findings highlight the importance of studying cognitive processes in more natural settings, where factors such as personal relevance, life history, and bodily contributions to cognition (e.g., limb, head, and body movements) are more readily revealed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Bias present in US federal agency power plant CO2 emissions data and implications for the US clean power plan

NASA Astrophysics Data System (ADS)

Gurney, K. R.; Huang, J.; Coltin, K.

2016-06-01

Power plants constitute roughly 40% of carbon dioxide (CO2) emissions in the United States. Climate change science, air pollution regulation, and potential carbon trading policies rely on accurate, unbiased quantification of these large point sources. Two US federal agencies—the Department of Energy and the Environmental Protection Agency—tabulate the emissions from US power plants using two different methodological approaches. We have analyzed those two data sets and have found that when averaged over all US facilities, the median percentage difference is less than 3%. However, this small difference masks large, non-Gaussian, positive and negative differences at individual facilities. For example, over the 2001-2009 time period, nearly one-half of the facilities have monthly emission differences that exceed roughly ±6% and one-fifth exceed roughly ±13%. It is currently not possible to assess whether one, or both, of the datasets examined here are responsible for the emissions difference. Differences this large at the individual facility level raise concerns regarding the operationalization of policy within the United States such as the recently announced Clean Power Plan. This policy relies on the achievement of state-level CO2 emission rate targets. When examined at the state-level we find that one-third of the states have differences that exceed 10% of their assigned reduction amount. Such levels of uncertainty raise concerns about the ability of individual states to accurately quantify emission rates in order to meet the regulatory targets.

Genetic Psychophysiology: advances, problems, and future directions

PubMed Central

Anokhin, Andrey P.

2014-01-01

This paper presents an overview of historical advances and the current state of genetic psychophysiology, a rapidly developing interdisciplinary research linking genetics, brain, and human behavior, discusses methodological problems, and outlines future directions of research. The main goals of genetic psychophysiology are to elucidate the neural pathways and mechanisms mediating genetic influences on cognition and emotion, identify intermediate brain-based phenotypes for psychopathology, and provide a functional characterization of genes being discovered by large association studies of behavioral phenotypes. Since the initiation of this neurogenetic approach to human individual differences in the 1970s, numerous twin and family studies have provided strong evidence for heritability of diverse aspects of brain function including resting-state brain oscillations, functional connectivity, and event-related neural activity in a variety of cognitive and emotion processing tasks, as well as peripheral psychophysiological responses. These data indicate large differences in the presence and strength of genetic influences across measures and domains, permitting the selection of heritable characteristics for gene finding studies. More recently, candidate gene association studies began to implicate specific genetic variants in different aspects of neurocognition. However, great caution is needed in pursuing this line of research due to its demonstrated proneness to generate false-positive findings. Recent developments in methods for physiological signal analysis, hemodynamic imaging, and genomic technologies offer new exciting opportunities for the investigation of the interplay between genetic and environmental factors in the development of individual differences in behavior, both normal and abnormal. PMID:24739435

Primary Mucinous Cystadenocarcinoma of the Breast: Cytologic Finding and Expression of MUC5 Are Different from Mucinous Carcinoma

PubMed Central

Kim, Sung Eun; Park, Ji Hye; Hong, SoonWon; Koo, Ja Seung; Jeong, Joon

2012-01-01

Mucinous cystadenocarcinoma (MCA) in the breast is a rare neoplasm. There have been 13 cases of primary breast MCA reported. The MCA presents as a large, partially cystic mass in postmenopausal woman with a good prognosis. The microscopic findings resemble those of ovarian, pancreatic, or appendiceal MCA. The aspiration findings showed mucin-containing cell clusters in the background of mucin and necrotic material. The cell clusters had intracytoplasmic mucin displacing atypical nuclei to the periphery. Histologically, the tumor revealed an abundant mucin pool with small floating clusters of mucin-containing tumor cells. There were also small cysts lined by a single layer of tall columnar mucinous cells, resembling those of the uterine endocervix. The cancer cells were positive for mucin (MUC) 5 and negative for MUC2 and MUC6. This mucin profile is different from ordinary mucinous carcinoma and may be a unique characteristic of breast MCA. PMID:23323116

Birth cohort and the specialization gap between same-sex and different-sex couples.

PubMed

Giddings, Lisa; Nunley, John M; Schneebaum, Alyssa; Zietz, Joachim

2014-04-01

We examine differences in household specialization between same-sex and different-sex couples within and across three birth cohorts: Baby Boomers, Generation X, and Generation Y. Using three measures of household specialization, we find that same-sex couples are less likely than their different-sex counterparts to exhibit a high degree of specialization. However, the "specialization gap" between same-sex and different-sex couples narrows across birth cohorts. These findings are indicative of a cohort effect. Our results are largely robust to the inclusion of a control for the presence of children and for subsets of couples with and without children. We provide three potential explanations for why the specialization gap narrows across cohorts. First, different-sex couples from more recent birth cohorts may have become more like same-sex couples in terms of household specialization. Second, social and legal changes may have prompted a greater degree of specialization within same-sex couples relative to different-sex couples. Last, the advent of reproductive technologies, which made having children easier for same-sex couples from more recent birth cohorts, could result in more specialization in such couples relative to different-sex couples.

Climate Change and Macro-Economic Cycles in Pre-Industrial Europe

PubMed Central

Pei, Qing; Zhang, David D.; Lee, Harry F.; Li, Guodong

2014-01-01

Climate change has been proven to be the ultimate cause of social crisis in pre-industrial Europe at a large scale. However, detailed analyses on climate change and macro-economic cycles in the pre-industrial era remain lacking, especially within different temporal scales. Therefore, fine-grained, paleo-climate, and economic data were employed with statistical methods to quantitatively assess the relations between climate change and agrarian economy in Europe during AD 1500 to 1800. In the study, the Butterworth filter was adopted to filter the data series into a long-term trend (low-frequency) and short-term fluctuations (high-frequency). Granger Causality Analysis was conducted to scrutinize the associations between climate change and macro-economic cycle at different frequency bands. Based on quantitative results, climate change can only show significant effects on the macro-economic cycle within the long-term. In terms of the short-term effects, society can relieve the influences from climate variations by social adaptation methods and self-adjustment mechanism. On a large spatial scale, temperature holds higher importance for the European agrarian economy than precipitation. By examining the supply-demand mechanism in the grain market, population during the study period acted as the producer in the long term, whereas as the consumer in the short term. These findings merely reflect the general interactions between climate change and macro-economic cycles at the large spatial region with a long-term study period. The findings neither illustrate individual incidents that can temporarily distort the agrarian economy nor explain some specific cases. In the study, the scale thinking in the analysis is raised as an essential methodological issue for the first time to interpret the associations between climatic impact and macro-economy in the past agrarian society within different temporal scales. PMID:24516601

Climate change and macro-economic cycles in pre-industrial europe.

PubMed

Pei, Qing; Zhang, David D; Lee, Harry F; Li, Guodong

2014-01-01

Climate change has been proven to be the ultimate cause of social crisis in pre-industrial Europe at a large scale. However, detailed analyses on climate change and macro-economic cycles in the pre-industrial era remain lacking, especially within different temporal scales. Therefore, fine-grained, paleo-climate, and economic data were employed with statistical methods to quantitatively assess the relations between climate change and agrarian economy in Europe during AD 1500 to 1800. In the study, the Butterworth filter was adopted to filter the data series into a long-term trend (low-frequency) and short-term fluctuations (high-frequency). Granger Causality Analysis was conducted to scrutinize the associations between climate change and macro-economic cycle at different frequency bands. Based on quantitative results, climate change can only show significant effects on the macro-economic cycle within the long-term. In terms of the short-term effects, society can relieve the influences from climate variations by social adaptation methods and self-adjustment mechanism. On a large spatial scale, temperature holds higher importance for the European agrarian economy than precipitation. By examining the supply-demand mechanism in the grain market, population during the study period acted as the producer in the long term, whereas as the consumer in the short term. These findings merely reflect the general interactions between climate change and macro-economic cycles at the large spatial region with a long-term study period. The findings neither illustrate individual incidents that can temporarily distort the agrarian economy nor explain some specific cases. In the study, the scale thinking in the analysis is raised as an essential methodological issue for the first time to interpret the associations between climatic impact and macro-economy in the past agrarian society within different temporal scales.

Implications of extreme sexual size dimorphism for thermoregulation in a freshwater turtle.

PubMed

Bulté, Grégory; Blouin-Demers, Gabriel

2010-02-01

Sexual size dimorphism (SSD) is a common phenomenon in animals. In many species females are substantially larger than males. Because body size plays a central role in modulating the body temperature (T (b)) of ectotherms, intersexual differences in body size may lead to important intersexual differences in thermoregulation. In addition, because SSD is realized by differences in growth rate and because growth rate is strongly temperature dependent in ectotherms, a conflict between male reproductive behaviour and thermoregulation may affect the expression of SSD. In this study, we investigated the thermal implications of SSD in a reptile exhibiting spectacular female-biased SSD: the northern map turtle (Graptemys geographica). Over three seasons, we collected >150,000 measurements of T (b) in free-ranging adult and juvenile northern map turtles using surgically implanted miniature temperature loggers. Northern map turtles exhibited seasonal patterns of thermoregulation typical of reptiles in northern latitudes, but we found that large adult females experienced a lower daily maximum T (b) and a narrower daily range of T (b) than adult males and small juvenile females. In addition, despite more time spent basking, large adult females were not able to thermoregulate as accurately as small turtles. Our findings strongly suggest that body size limits the ability to thermoregulate accurately in large females. By comparing thermoregulatory patterns between adult males and juvenile females of similar body size, we found no evidence that male reproductive behaviours are an impediment to thermoregulation. We also quantified the thermal significance of basking behaviour. We found, contrary to previous findings, that aerial basking allows northern map turtles to raise their T (b) substantially above water temperature, indicating that basking behaviour likely plays an important role in thermoregulation.

Citizen Astronomy in China: An Overview

NASA Astrophysics Data System (ADS)

Ye, Quan-Zhi

2018-01-01

Citizen astronomers have benefited from technological advancements in the recent decades as they fill the scientific gaps left by professional astronomers, in the areas such as time domain observations, visual classification and data mining. Here I present an overview of the current status of citizen astronomy in China. Chinese citizen astronomers have made a visible contribution in the discoveries of new objects; however, comparing to their counterparts in the western world, they appear to be less interested in researches that do not involve making new discovery, such as visual classification, long-term monitoring of objects, and data mining. From a questionnaire survey that aimed to investigate the motivation of Chinese citizen astronomers, we find that this population is predominantly male (92%) who mostly reside in economically developed provinces. A large fraction (69%) of the respondents are students and young professionals younger than the age of 25, which differs significantly from the occupation and age distribution of typical Chinese Internet users as well as the user distribution of large international citizen science projects such as the Galaxy Zoo. This suggests that youth generation in China is more willing to participate citizen astronomy research than average generation. Additionally, we find that interests in astronomy, desire to learn new knowledges, have a fun experience and meet new friends in the community are all important driving factors for Chinese citizen astronomers to participate research. This also differs from their counterparts in western countries. With a large youth population that is interested in astronomy as well as a number of large astronomical facilities that are being planned or built, we believe that citizen astronomy in China has a vast potential. Timely and proper guidance from the professionals will be essential to help citizen astronomers to fulfill this potential.

Non-surgical treatment of hallux valgus: a current practice survey of Australian podiatrists.

PubMed

Hurn, Sheree E; Vicenzino, Bill T; Smith, Michelle D

2016-01-01

Patients with hallux valgus (HV) frequently present to podiatrists for non-surgical management, with a wide range of concerns including pain, footwear difficulty and quality of life impacts. There is little research evidence guiding podiatrists' clinical decisions surrounding non-surgical management of HV. Thus practitioners rely largely upon clinical experience and expert opinion. This survey was conducted to determine whether a consensus exists among Australian podiatrists regarding non-surgical treatment of HV, and secondly to explore common presenting concerns and physical examination findings associated with HV. An online survey was distributed to Australian podiatrists in mid-2013 via the professional association in each state (approximately 1900 members). Podiatrists indicated common treatments recommended, presenting problems and physical examination findings associated with HV in juveniles, adults and older adults. Proportions were calculated to determine the most common responses, and Chi-squared tests were used to examine differences in treatment recommendations according to HV patient age group and podiatrist demographics. Of 210 survey respondents, 65 % (136) were female and 80 % (168) were private practitioners. Complete survey responses were received from 159 podiatrists for juvenile HV, 146 for adults and 141 for older adults. Seven different non-surgical treatment options were commonly recommended (by >50 % podiatrists), although recommendations differed between adult, older adult and juvenile HV. Common treatments included footwear advice or modification, custom and prefabricated orthotic devices, addition of padding, and muscle strengthening/retraining exercises. Padding was more likely to be utilised in older adults, while exercises were more likely to be prescribed for juveniles. A diverse range of presenting problems and physical examination findings were reported to be associated with HV. Despite the lack of empirical evidence in this area, there appears to be a consensus among Australian podiatrists regarding non-surgical management of HV, and these recommendations are largely aligned with available clinical consensus documents. Presenting concerns and physical examination findings associated with HV are diverse and have implications for treatment decisions. Management strategies differ across patient age groups, thus any updated clinical guidelines should differentiate between adult and juvenile HV. This study provides useful data to inform clinical practice, education, policy and future research.

Restoration ecology: two-sex dynamics and cost minimization.

PubMed

Molnár, Ferenc; Caragine, Christina; Caraco, Thomas; Korniss, Gyorgy

2013-01-01

We model a spatially detailed, two-sex population dynamics, to study the cost of ecological restoration. We assume that cost is proportional to the number of individuals introduced into a large habitat. We treat dispersal as homogeneous diffusion in a one-dimensional reaction-diffusion system. The local population dynamics depends on sex ratio at birth, and allows mortality rates to differ between sexes. Furthermore, local density dependence induces a strong Allee effect, implying that the initial population must be sufficiently large to avert rapid extinction. We address three different initial spatial distributions for the introduced individuals; for each we minimize the associated cost, constrained by the requirement that the species must be restored throughout the habitat. First, we consider spatially inhomogeneous, unstable stationary solutions of the model's equations as plausible candidates for small restoration cost. Second, we use numerical simulations to find the smallest rectangular cluster, enclosing a spatially homogeneous population density, that minimizes the cost of assured restoration. Finally, by employing simulated annealing, we minimize restoration cost among all possible initial spatial distributions of females and males. For biased sex ratios, or for a significant between-sex difference in mortality, we find that sex-specific spatial distributions minimize the cost. But as long as the sex ratio maximizes the local equilibrium density for given mortality rates, a common homogeneous distribution for both sexes that spans a critical distance yields a similarly low cost.

Extended Twin Study of Alcohol Use in Virginia and Australia.

PubMed

Verhulst, Brad; Neale, Michael C; Eaves, Lindon J; Medland, Sarah E; Heath, Andrew C; Martin, Nicholas G; Maes, Hermine H

2018-06-01

Drinking alcohol is a normal behavior in many societies, and prior studies have demonstrated it has both genetic and environmental sources of variation. Using two very large samples of twins and their first-degree relatives (Australia ≈ 20,000 individuals from 8,019 families; Virginia ≈ 23,000 from 6,042 families), we examine whether there are differences: (1) in the genetic and environmental factors that influence four interrelated drinking behaviors (quantity, frequency, age of initiation, and number of drinks in the last week), (2) between the twin-only design and the extended twin design, and (3) the Australian and Virginia samples. We find that while drinking behaviors are interrelated, there are substantial differences in the genetic and environmental architectures across phenotypes. Specifically, drinking quantity, frequency, and number of drinks in the past week have large broad genetic variance components, and smaller but significant environmental variance components, while age of onset is driven exclusively by environmental factors. Further, the twin-only design and the extended twin design come to similar conclusions regarding broad-sense heritability and environmental transmission, but the extended twin models provide a more nuanced perspective. Finally, we find a high level of similarity between the Australian and Virginian samples, especially for the genetic factors. The observed differences, when present, tend to be at the environmental level. Implications for the extended twin model and future directions are discussed.

Restoration Ecology: Two-Sex Dynamics and Cost Minimization

PubMed Central

Molnár, Ferenc; Caragine, Christina; Caraco, Thomas; Korniss, Gyorgy

2013-01-01

We model a spatially detailed, two-sex population dynamics, to study the cost of ecological restoration. We assume that cost is proportional to the number of individuals introduced into a large habitat. We treat dispersal as homogeneous diffusion in a one-dimensional reaction-diffusion system. The local population dynamics depends on sex ratio at birth, and allows mortality rates to differ between sexes. Furthermore, local density dependence induces a strong Allee effect, implying that the initial population must be sufficiently large to avert rapid extinction. We address three different initial spatial distributions for the introduced individuals; for each we minimize the associated cost, constrained by the requirement that the species must be restored throughout the habitat. First, we consider spatially inhomogeneous, unstable stationary solutions of the model’s equations as plausible candidates for small restoration cost. Second, we use numerical simulations to find the smallest rectangular cluster, enclosing a spatially homogeneous population density, that minimizes the cost of assured restoration. Finally, by employing simulated annealing, we minimize restoration cost among all possible initial spatial distributions of females and males. For biased sex ratios, or for a significant between-sex difference in mortality, we find that sex-specific spatial distributions minimize the cost. But as long as the sex ratio maximizes the local equilibrium density for given mortality rates, a common homogeneous distribution for both sexes that spans a critical distance yields a similarly low cost. PMID:24204810

Socioeconomic Segregation in Large Cities in France and the United States.

PubMed

Quillian, Lincoln; Lagrange, Hugues

2016-08-01

Past cross-national comparisons of socioeconomic segregation have been undercut by lack of comparability in measures, data, and concepts. Using IRIS data from the French Census of 2008 and the French Ministry of Finance as well as tract data from the American Community Survey (2006-2010) and the U.S. Department of Housing and Urban Development Picture of Subsidized Households, and constructing measures to be as similar as possible, we compare socioeconomic segregation in metropolitan areas with a population of more than 1 million in France and the United States. We find much higher socioeconomic segregation in large metropolitan areas in the United States than in France. We also find (1) a strong pattern of low-income neighborhoods in central cities and high-income neighborhoods in suburbs in the United States, but varying patterns across metropolitan areas in France; (2) that high-income persons are the most segregated group in both countries; (3) that the shares of neighborhood income differences that can be explained by neighborhood racial/ethnic composition are similar in France and the United States; and (4) that government-assisted housing is disproportionately located in the poorest neighborhoods in the United States but is spread across many neighborhood income levels in France. We conclude that differences in government provision of housing assistance and levels of income inequality are likely important contributing factors to the Franco-U.S. difference in socioeconomic segregation.

Investigation of gold nanoparticle radiosensitization mechanisms using a free radical scavenger and protons of different energies.

PubMed

Jeynes, J C G; Merchant, M J; Spindler, A; Wera, A-C; Kirkby, K J

2014-11-07

Gold nanoparticles (GNPs) have been shown to sensitize cancer cells to x-ray radiation, particularly at kV energies where photoelectric interactions dominate and the high atomic number of gold makes a large difference to x-ray absorption. Protons have a high cross-section for gold at a large range of relevant clinical energies, and so potentially could be used with GNPs for increased therapeutic effect.Here, we investigate the contribution of secondary electron emission to cancer cell radiosensitization and investigate how this parameter is affected by proton energy and a free radical scavenger. We simulate the emission from a realistic cell phantom containing GNPs after traversal by protons and x-rays with different energies. We find that with a range of proton energies (1-250 MeV) there is a small increase in secondaries compared to a much larger increase with x-rays. Secondary electrons are known to produce toxic free radicals. Using a cancer cell line in vitro we find that a free radical scavenger has no protective effect on cells containing GNPs irradiated with 3 MeV protons, while it does protect against cells irradiated with x-rays. We conclude that GNP generated free radicals are a major cause of radiosensitization and that there is likely to be much less dose enhancement effect with clinical proton beams compared to x-rays.

Butterfly magnetoresistance, quasi-2D Dirac Fermi surface and topological phase transition in ZrSiS

PubMed Central

Ali, Mazhar N.; Schoop, Leslie M.; Garg, Chirag; Lippmann, Judith M.; Lara, Erik; Lotsch, Bettina; Parkin, Stuart S. P.

2016-01-01

Magnetoresistance (MR), the change of a material’s electrical resistance in response to an applied magnetic field, is a technologically important property that has been the topic of intense study for more than a quarter century. We report the observation of an unusual “butterfly”-shaped titanic angular magnetoresistance (AMR) in the nonmagnetic Dirac material, ZrSiS, which we find to be the most conducting sulfide known, with a 2-K resistivity as low as 48(4) nΩ⋅cm. The MR in ZrSiS is large and positive, reaching nearly 1.8 × 105 percent at 9 T and 2 K at a 45° angle between the applied current (I || a) and the applied field (90° is H || c). Approaching 90°, a “dip” is seen in the AMR, which, by analyzing Shubnikov de Haas oscillations at different angles, we find to coincide with a very sharp topological phase transition unlike any seen in other known Dirac/Weyl materials. We find that ZrSiS has a combination of two-dimensional (2D) and 3D Dirac pockets comprising its Fermi surface and that the combination of high-mobility carriers and multiple pockets in ZrSiS allows for large property changes to occur as a function of angle between applied fields. This makes it a promising platform to study the physics stemming from the coexistence of 2D and 3D Dirac electrons as well as opens the door to creating devices focused on switching between different parts of the Fermi surface and different topological states. PMID:28028541

Polarity Comparison Between the Coronal PFSS Model Field and the Heliospheric Magnetic Field at 1 AU Over Solar Cycles 21-24

NASA Astrophysics Data System (ADS)

Koskela, J. S.; Virtanen, I. I.; Mursula, K.

2015-12-01

The solar coronal magnetic field forms an important link between the underlying source in the solar photosphere and the heliospheric magnetic field (HMF). The coronal field has traditionally been calculated from the photospheric observations using various magnetic field models between the photosphere and the corona, in particular the potential field source surface (PFSS) model. Despite its simplicity, the predictions of the PFSS model generally agree quite well with the heliospheric observations and match very well with the predictions of more elaborate models. We make here a detailed comparison between the predictions of the PFSS model with the HMF field observed at 1 AU. We use the photospheric field measured at the Wilcox Solar Observatory, SDO/HMI, SOHO/MDI and SOLIS, and the heliospheric magnetic field measurements at 1 AU collected within the OMNI 2 dataset. This database covers the solar cycles 21-24. We use different source surface distances and different numbers of harmonic components for the PFSS model. We find an optimum polarity match between the coronal field and the HMF for source surface distance of 3.5 Rs. Increasing the number of harmonic components beyond the quadrupole does not essentially improve polarity agreement, indicating that the large scale structure of the HMF at 1 AU is responsible for the agreement while the small scale structure is greatly modified between corona and 1 AU. We also discuss the solar cycle evolution of polarity match and find that the PFSS model prediction is most reliable during the declining phase of the solar cycle. We also find large differences in match percentage between northern and southern hemispheres during the times of systematic southward shift of the heliospheric current sheet (the Bashful ballerina).

DO NOT FORGET THE FOREST FOR THE TREES: THE STELLAR-MASS HALO-MASS RELATION IN DIFFERENT ENVIRONMENTS

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

Tonnesen, Stephanie; Cen, Renyue, E-mail: stonnes@gmail.com, E-mail: cen@astro.princeton.edu

2015-10-20

The connection between dark matter halos and galactic baryons is often not well constrained nor well resolved in cosmological hydrodynamical simulations. Thus, halo occupation distribution models that assign galaxies to halos based on halo mass are frequently used to interpret clustering observations, even though it is well known that the assembly history of dark matter halos is related to their clustering. In this paper we use high-resolution hydrodynamical cosmological simulations to compare the halo and stellar mass growth of galaxies in a large-scale overdensity to those in a large-scale underdensity (on scales of about 20 Mpc). The simulation reproduces assemblymore » bias, in which halos have earlier formation times in overdense environments than in underdense regions. We find that the ratio of stellar mass to halo mass is larger in overdense regions in central galaxies residing in halos with masses between 10{sup 11} and 10{sup 12.9} M{sub ⊙}. When we force the local density (within 2 Mpc) at z = 0 to be the same for galaxies in the large-scale over- and underdensities, we find the same results. We posit that this difference can be explained by a combination of earlier formation times, more interactions at early times with neighbors, and more filaments feeding galaxies in overdense regions. This result puts the standard practice of assigning stellar mass to halos based only on their mass, rather than considering their larger environment, into question.« less

Incorporating Functional Annotations for Fine-Mapping Causal Variants in a Bayesian Framework Using Summary Statistics.

PubMed

Chen, Wenan; McDonnell, Shannon K; Thibodeau, Stephen N; Tillmans, Lori S; Schaid, Daniel J

2016-11-01

Functional annotations have been shown to improve both the discovery power and fine-mapping accuracy in genome-wide association studies. However, the optimal strategy to incorporate the large number of existing annotations is still not clear. In this study, we propose a Bayesian framework to incorporate functional annotations in a systematic manner. We compute the maximum a posteriori solution and use cross validation to find the optimal penalty parameters. By extending our previous fine-mapping method CAVIARBF into this framework, we require only summary statistics as input. We also derived an exact calculation of Bayes factors using summary statistics for quantitative traits, which is necessary when a large proportion of trait variance is explained by the variants of interest, such as in fine mapping expression quantitative trait loci (eQTL). We compared the proposed method with PAINTOR using different strategies to combine annotations. Simulation results show that the proposed method achieves the best accuracy in identifying causal variants among the different strategies and methods compared. We also find that for annotations with moderate effects from a large annotation pool, screening annotations individually and then combining the top annotations can produce overly optimistic results. We applied these methods on two real data sets: a meta-analysis result of lipid traits and a cis-eQTL study of normal prostate tissues. For the eQTL data, incorporating annotations significantly increased the number of potential causal variants with high probabilities. Copyright © 2016 by the Genetics Society of America.

Inferring Single Neuron Properties in Conductance Based Balanced Networks

PubMed Central

Pool, Román Rossi; Mato, Germán

2011-01-01

Balanced states in large networks are a usual hypothesis for explaining the variability of neural activity in cortical systems. In this regime the statistics of the inputs is characterized by static and dynamic fluctuations. The dynamic fluctuations have a Gaussian distribution. Such statistics allows to use reverse correlation methods, by recording synaptic inputs and the spike trains of ongoing spontaneous activity without any additional input. By using this method, properties of the single neuron dynamics that are masked by the balanced state can be quantified. To show the feasibility of this approach we apply it to large networks of conductance based neurons. The networks are classified as Type I or Type II according to the bifurcations which neurons of the different populations undergo near the firing onset. We also analyze mixed networks, in which each population has a mixture of different neuronal types. We determine under which conditions the intrinsic noise generated by the network can be used to apply reverse correlation methods. We find that under realistic conditions we can ascertain with low error the types of neurons present in the network. We also find that data from neurons with similar firing rates can be combined to perform covariance analysis. We compare the results of these methods (that do not requite any external input) to the standard procedure (that requires the injection of Gaussian noise into a single neuron). We find a good agreement between the two procedures. PMID:22016730

Emission-Line Galaxies from the PEARS Hubble Ultra Deep Field: A 2-D Detection Method and First Results

NASA Technical Reports Server (NTRS)

Gardner, J. P.; Straughn, Amber N.; Meurer, Gerhardt R.; Pirzkal, Norbert; Cohen, Seth H.; Malhotra, Sangeeta; Rhoads, james; Windhorst, Rogier A.; Gardner, Jonathan P.; Hathi, Nimish P.;

Similarities and differences in dream content at the cross-cultural, gender, and individual levels.

PubMed

William Domhoff, G; Schneider, Adam

2008-12-01

The similarities and differences in dream content at the cross-cultural, gender, and individual levels provide one starting point for carrying out studies that attempt to discover correspondences between dream content and various types of waking cognition. Hobson and Kahn's (Hobson, J. A., & Kahn, D. (2007). Dream content: Individual and generic aspects. Consciousness and Cognition, 16, 850-858.) conclusion that dream content may be more generic than most researchers realize, and that individual differences are less salient than usually thought, provides the occasion for a review of findings based on the Hall and Van de Castle (Hall, C., & Van de Castle, R. (1966). The content analysis of dreams. New York: Appleton-Century-Crofts.) coding system for the study of dream content. Then new findings based on a computationally intensive randomization strategy are presented to show the minimum sample sizes needed to detect gender and individual differences in dream content. Generally speaking, sample sizes of 100-125 dream reports are needed because most dream elements appear in less than 50% of dream reports and the magnitude of the differences usually is not large.

Structural connectivity of the developing human amygdala.

PubMed

Saygin, Zeynep M; Osher, David E; Koldewyn, Kami; Martin, Rebecca E; Finn, Amy; Saxe, Rebecca; Gabrieli, John D E; Sheridan, Margaret

2015-01-01

A large corpus of research suggests that there are changes in the manner and degree to which the amygdala supports cognitive and emotional function across development. One possible basis for these developmental differences could be the maturation of amygdalar connections with the rest of the brain. Recent functional connectivity studies support this conclusion, but the structural connectivity of the developing amygdala and its different nuclei remains largely unstudied. We examined age related changes in the DWI connectivity fingerprints of the amygdala to the rest of the brain in 166 individuals of ages 5-30. We also developed a model to predict age based on individual-subject amygdala connectivity, and identified the connections that were most predictive of age. Finally, we segmented the amygdala into its four main nucleus groups, and examined the developmental changes in connectivity for each nucleus. We observed that with age, amygdalar connectivity becomes increasingly sparse and localized. Age related changes were largely localized to the subregions of the amygdala that are implicated in social inference and contextual memory (the basal and lateral nuclei). The central nucleus' connectivity also showed differences with age but these differences affected fewer target regions than the basal and lateral nuclei. The medial nucleus did not exhibit any age related changes. These findings demonstrate increasing specificity in the connectivity patterns of amygdalar nuclei across age.

Not All Larvae Stay Close to Home: Insights into Marine Population Connectivity with a Focus on the Brown Surgeonfish (Acanthurus nigrofuscus)

PubMed Central

Eble, Jeff A.; Rocha, Luiz A.; Craig, Matthew T.; Bowen, Brian W.

2014-01-01

Recent reports of localized larval recruitment in predominately small-range fishes are countered by studies that show high genetic connectivity across large oceanic distances. This discrepancy may result from the different timescales over which genetic and demographic processes operate or rather may indicate regular long-distance dispersal in some species. Here, we contribute an analysis of mtDNA cytochrome b diversity in the widely distributed Brown Surgeonfish (Acanthurus nigrofuscus; N = 560), which revealed significant genetic structure only at the extremes of the range (ΦCT = 0.452; P < .001). Collections from Hawaii to the Eastern Indian Ocean comprise one large, undifferentiated population. This pattern of limited genetic subdivision across reefs of the central Indo-Pacific has been observed in a number of large-range reef fishes. Conversely, small-range fishes are often deeply structured over the same area. These findings demonstrate population connectivity differences among species at biogeographic and evolutionary timescales, which likely translates into differences in dispersal ability at ecological and demographic timescales. While interspecific differences in population connectivity complicate the design of management strategies, the integration of multiscale connectivity patterns into marine resource planning will help ensure long-term ecosystem stability by preserving functionally diverse communities. PMID:25505914

Design and analysis of large-scale biological rhythm studies: a comparison of algorithms for detecting periodic signals in biological data

PubMed Central

Deckard, Anastasia; Anafi, Ron C.; Hogenesch, John B.; Haase, Steven B.; Harer, John

2013-01-01

Motivation: To discover and study periodic processes in biological systems, we sought to identify periodic patterns in their gene expression data. We surveyed a large number of available methods for identifying periodicity in time series data and chose representatives of different mathematical perspectives that performed well on both synthetic data and biological data. Synthetic data were used to evaluate how each algorithm responds to different curve shapes, periods, phase shifts, noise levels and sampling rates. The biological datasets we tested represent a variety of periodic processes from different organisms, including the cell cycle and metabolic cycle in Saccharomyces cerevisiae, circadian rhythms in Mus musculus and the root clock in Arabidopsis thaliana. Results: From these results, we discovered that each algorithm had different strengths. Based on our findings, we make recommendations for selecting and applying these methods depending on the nature of the data and the periodic patterns of interest. Additionally, these results can also be used to inform the design of large-scale biological rhythm experiments so that the resulting data can be used with these algorithms to detect periodic signals more effectively. Contact: anastasia.deckard@duke.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:24058056

Sperm competition and reproductive mode influence sperm dimensions and structure among snakes.

PubMed

Tourmente, Maximiliano; Gomendio, Montserrat; Roldan, Eduardo R S; Giojalas, Laura C; Chiaraviglio, Margarita

2009-10-01

The role of sperm competition in increasing sperm length is a controversial issue, because findings from different taxa seem contradictory. We present a comparative study of 25 species of snakes with different levels of sperm competition to test whether it influences the size and structure of different sperm components. We show that, as levels of sperm competition increase, so does sperm length, and that this elongation is largely explained by increases in midpiece length. In snakes, the midpiece is comparatively large and it contains structures, which in other taxa are present in the rest of the flagellum, suggesting that it may integrate some of its functions. Thus, increases in sperm midpiece size would result in more energy as well as greater propulsion force. Sperm competition also increases the area occupied by the fibrous sheath and outer dense fibers within the sperm midpiece, revealing for the first time an effect upon structural elements within the sperm. Finally, differences in male-male encounter rates between oviparous and viviparous species seem to lead to differences in levels of sperm competition. We conclude that the influence of sperm competition upon different sperm components varies between taxa, because their structure and function is different.

GAMA/H-ATLAS: a meta-analysis of SFR indicators - comprehensive measures of the SFR-M* relation and cosmic star formation history at z < 0.4

NASA Astrophysics Data System (ADS)

Davies, L. J. M.; Driver, S. P.; Robotham, A. S. G.; Grootes, M. W.; Popescu, C. C.; Tuffs, R. J.; Hopkins, A.; Alpaslan, M.; Andrews, S. K.; Bland-Hawthorn, J.; Bremer, M. N.; Brough, S.; Brown, M. J. I.; Cluver, M. E.; Croom, S.; da Cunha, E.; Dunne, L.; Lara-López, M. A.; Liske, J.; Loveday, J.; Moffett, A. J.; Owers, M.; Phillipps, S.; Sansom, A. E.; Taylor, E. N.; Michalowski, M. J.; Ibar, E.; Smith, M.; Bourne, N.

2016-09-01

We present a meta-analysis of star formation rate (SFR) indicators in the Galaxy And Mass Assembly (GAMA) survey, producing 12 different SFR metrics and determining the SFR-M* relation for each. We compare and contrast published methods to extract the SFR from each indicator, using a well-defined local sample of morphologically selected spiral galaxies, which excludes sources which potentially have large recent changes to their SFR. The different methods are found to yield SFR-M* relations with inconsistent slopes and normalizations, suggesting differences between calibration methods. The recovered SFR-M* relations also have a large range in scatter which, as SFRs of the targets may be considered constant over the different time-scales, suggests differences in the accuracy by which methods correct for attenuation in individual targets. We then recalibrate all SFR indicators to provide new, robust and consistent luminosity-to-SFR calibrations, finding that the most consistent slopes and normalizations of the SFR-M* relations are obtained when recalibrated using the radiation transfer method of Popescu et al. These new calibrations can be used to directly compare SFRs across different observations, epochs and galaxy populations. We then apply our calibrations to the GAMA II equatorial data set and explore the evolution of star formation in the local Universe. We determine the evolution of the normalization to the SFR-M* relation from 0 < z < 0.35 - finding consistent trends with previous estimates at 0.3 < z < 1.2. We then provide the definitive z < 0.35 cosmic star formation history, SFR-M* relation and its evolution over the last 3 billion years.

The new science of cognitive sex differences.

PubMed

Miller, David I; Halpern, Diane F

2014-01-01

Surprising new findings indicate that many conclusions about sex differences and similarities in cognitive abilities need to be reexamined. Cognitive sex differences are changing, decreasing for some tasks whereas remaining stable or increasing for other tasks. Some sex differences are detected in infancy, but the data are complex and depend on task characteristics. Diverse disciplines have revolutionized our understanding of why these differences exist. For instance, fraternal-twin studies align with earlier literature to help establish the role of prenatal androgens and large international datasets help explain how cultural factors such as economic prosperity and gender equity affect females and males differently. Understanding how biological and environmental factors interact could help maximize cognitive potential and address pressing societal issues. Copyright © 2013 Elsevier Ltd. All rights reserved.

Functional and topological characteristics of mammalian regulatory domains

PubMed Central

Symmons, Orsolya; Uslu, Veli Vural; Tsujimura, Taro; Ruf, Sandra; Nassari, Sonya; Schwarzer, Wibke; Ettwiller, Laurence; Spitz, François

2014-01-01

Long-range regulatory interactions play an important role in shaping gene-expression programs. However, the genomic features that organize these activities are still poorly characterized. We conducted a large operational analysis to chart the distribution of gene regulatory activities along the mouse genome, using hundreds of insertions of a regulatory sensor. We found that enhancers distribute their activities along broad regions and not in a gene-centric manner, defining large regulatory domains. Remarkably, these domains correlate strongly with the recently described TADs, which partition the genome into distinct self-interacting blocks. Different features, including specific repeats and CTCF-binding sites, correlate with the transition zones separating regulatory domains, and may help to further organize promiscuously distributed regulatory influences within large domains. These findings support a model of genomic organization where TADs confine regulatory activities to specific but large regulatory domains, contributing to the establishment of specific gene expression profiles. PMID:24398455

Systematic observations of the slip pulse properties of large earthquake ruptures

USGS Publications Warehouse

Melgar, Diego; Hayes, Gavin

2017-01-01

In earthquake dynamics there are two end member models of rupture: propagating cracks and self-healing pulses. These arise due to different properties of faults and have implications for seismic hazard; rupture mode controls near-field strong ground motions. Past studies favor the pulse-like mode of rupture; however, due to a variety of limitations, it has proven difficult to systematically establish their kinematic properties. Here we synthesize observations from a database of >150 rupture models of earthquakes spanning M7–M9 processed in a uniform manner and show the magnitude scaling properties of these slip pulses indicates self-similarity. Further, we find that large and very large events are statistically distinguishable relatively early (at ~15 s) in the rupture process. This suggests that with dense regional geophysical networks strong ground motions from a large rupture can be identified before their onset across the source region.

The Role of Permanent Income and Demographics in Black/White Differences in Wealth

ERIC Educational Resources Information Center

Altonji, Joseph G.; Doraszelski, Ulrich

2005-01-01

A large part of the racial disparity with wealth holdings with income and demographic variables can be explained by examining the wealth model of a sample of whites, but only a small fraction when we use a black wealth model. Research finds a higher self-employment rate and a stronger link between self-employment and wealth for whites than for…

Customization of Discriminant Function Analysis for Prediction of Solar Flares

DTIC Science & Technology

2005-03-01

lives such as telecommunication, commercial airlines, electrical power , wireless services, and terrestrial weather tracking and forecasting...the 1800’s can wreak havoc on today’s power , fuel, and telecommunication lines and finds its origin in solar activity. Enormous amounts of solar...inducing potential differences across large areas of the surface. Earth-bound power , fuel, and telecommunication lines grounded to the Earth provide an

Contrasts in Openness toward Mobile Learning in the Classroom: A Study of Elementary, Middle and High School Teachers

ERIC Educational Resources Information Center

Christensen, Rhonda; Knezek, Gerald

2017-01-01

In a study involving 1414 elementary, middle school, and high school teachers from a large school district in the southwestern USA, the authors examine the similarities and differences among teachers at the three levels of K-12 education common in US school systems: elementary, middle school and high school. Major findings are that elementary…

The Trouble with Boys: Social Influences and the Gender Gap in Disruptive Behavior. NBER Working Paper No. 17541

ERIC Educational Resources Information Center

Bertrand, Marianne; Pan, Jessica

2011-01-01

This paper explores the importance of the home and school environments in explaining the gender gap in disruptive behavior. We document large differences in the gender gap across key features of the home environment--boys do especially poorly in broken families. In contrast, we find little impact of the early school environment on non-cognitive…

Learning to Perform? A Comparison of Learning Practices and Organizational Performance in Profit- and Non-Profit-Making Sectors in the UK

ERIC Educational Resources Information Center

Birdi, Kamal S.; Patterson, Malcolm G.; Wood, Stephen J.

2007-01-01

To date, much of the research on employee development activities and organizational performance has been conducted in private sector organizations, with the largely untested assumption that the same findings will apply to other sectors. This paper addresses the deficit by describing a study comparing differences in the use of employee learning…

Accounting for Risk of Non-Completion in Private and Social Rates of Return to Higher Education

ERIC Educational Resources Information Center

Toutkoushian, Robert K.; Shafiq, M. Najeeb; Trivette, Michael J.

2013-01-01

Conventional studies of the private and social rates of return to a Bachelor's degree focus on the earnings difference between Bachelor degree holders and high school graduates, and find that there are large rates of return for degree recipients. The estimates in these studies, however, do not take into account the risk of not completing a degree.…

Innovation in Teaching and Learning in Vocational Education and Training: International Perspectives. Research Overview

ERIC Educational Resources Information Center

Hillier, Yvonne

2009-01-01

How can people know what vocational education and training (VET) practitioners are doing in other countries? Often people who are finding new and different ways to teach and help people learn do not publish what they are doing. However, a large number of relevant web-based networks exist and the author was able to interrogate these for examples of…

The Structure and Determinants of Expected and Actual Starting Salaries of Higher Education Students in Germany: Identical or Different?

ERIC Educational Resources Information Center

Frick, Bernd; Maihaus, Michael

2016-01-01

Using two representative samples of some 74,000 students and 11,000 graduates, respectively, we analyse the accuracy of students' wage expectations given their individual characteristics. We find that students are aware of the effects of most of their own characteristics, as a large number of determinants of expected and realised salaries do not…

An Analysis of the Application and Enrollment Processes for In-State and Out-of-State Students at a Large Public University.

ERIC Educational Resources Information Center

Curs, Bradley; Singell, Larry D., Jr.

2002-01-01

Two separate empirical analyses use time-series data for the University of Oregon to estimate and compare the responsiveness of applicants and enrollees to variations in the net price. Results show that prior studies may understate student price responsiveness. Finds that elasticity estimates differ for in-state and out-of-state students. Suggests…

Achieving Equity and Quality in Japanese Elementary Schools: Balancing the Roles of State, Teachers, and Students

ERIC Educational Resources Information Center

Parmenter, Lynne

2016-01-01

The aim of this paper is to explore perspectives on equity, quality, motivation, and resilience by focusing in depth on the perspectives of educators in one small, semi-rural school in Japan. The paper is intended to provide rich, in-depth data and discussion as a way of providing insights from different perspectives into findings from large-scale…

Effects of motor congruence on visual working memory.

PubMed

Quak, Michel; Pecher, Diane; Zeelenberg, Rene

2014-10-01

Grounded-cognition theories suggest that memory shares processing resources with perception and action. The motor system could be used to help memorize visual objects. In two experiments, we tested the hypothesis that people use motor affordances to maintain object representations in working memory. Participants performed a working memory task on photographs of manipulable and nonmanipulable objects. The manipulable objects were objects that required either a precision grip (i.e., small items) or a power grip (i.e., large items) to use. A concurrent motor task that could be congruent or incongruent with the manipulable objects caused no difference in working memory performance relative to nonmanipulable objects. Moreover, the precision- or power-grip motor task did not affect memory performance on small and large items differently. These findings suggest that the motor system plays no part in visual working memory.

cOSPREY: A Cloud-Based Distributed Algorithm for Large-Scale Computational Protein Design

PubMed Central

Pan, Yuchao; Dong, Yuxi; Zhou, Jingtian; Hallen, Mark; Donald, Bruce R.; Xu, Wei

2016-01-01

Abstract Finding the global minimum energy conformation (GMEC) of a huge combinatorial search space is the key challenge in computational protein design (CPD) problems. Traditional algorithms lack a scalable and efficient distributed design scheme, preventing researchers from taking full advantage of current cloud infrastructures. We design cloud OSPREY (cOSPREY), an extension to a widely used protein design software OSPREY, to allow the original design framework to scale to the commercial cloud infrastructures. We propose several novel designs to integrate both algorithm and system optimizations, such as GMEC-specific pruning, state search partitioning, asynchronous algorithm state sharing, and fault tolerance. We evaluate cOSPREY on three different cloud platforms using different technologies and show that it can solve a number of large-scale protein design problems that have not been possible with previous approaches. PMID:27154509

Direct observation of gold nanoparticle assemblies with the porin MspA on mica.

PubMed

Basel, Matthew T; Dani, Raj Kumar; Kang, Myungshim; Pavlenok, Mikhail; Chikan, Viktor; Smith, Paul E; Niederweis, Michael; Bossmann, Stefan H

2009-02-24

The octameric porin MspA from Mycobacterium smegmatis is sufficiently stable to form a nonmembrane-supported stand-alone porin on mica surfaces. About 98% of all MspA octamers were found to stand upright on mica, with their periplasmic loop regions bound to the hydrophilic mica surface. Both, small (d = 3.7 nm) and large (d = 17 nm) gold nanoparticles bind to MspA, however, in different positions: small gold nanoparticles bind within the MspA pore, whereas the large gold nanoparticles bind to the upper region of MspA. These experiments demonstrate that gold nanoparticles can be positioned at different, well-defined distances from the underlying surface using the MspA pore as a template. These findings represent a significant step toward the use of electrically insulating stable proteins in combination with metal nanoparticles in nanodevices.

Domoic acid excretion in dungeness crabs, razor clams and mussels.

PubMed

Schultz, Irvin R; Skillman, Ann; Woodruff, Dana

2008-07-01

Domoic acid (DA) is a neurotoxic amino acid produced by several marine algal species of the Pseudo-nitzschia (PN) genus. We studied the elimination of DA from hemolymph after intravascular (IV) injection in razor clams (Siliqua patula), mussels (Mytilus edulis) and Dungeness crabs (Cancer magister). Crabs were also injected with two other organic acids, dichloroacetic acid (DCAA) and kainic acid (KA). For IV dosing, hemolymph was repetitively sampled and DA concentrations measured by HPLC-UV. Toxicokinetic analysis of DA in crabs suggested most of the injected dose remained within hemolymph compartment with little extravascular distribution. This observation is in sharp contrast to results obtained from clams and mussels which exhibited similarly large apparent volumes of distribution despite large differences in overall clearance. These findings suggest fundamentally different storage and elimination processes are occurring for DA between bivalves and crabs.

Pathway Distiller - multisource biological pathway consolidation

PubMed Central

2012-01-01

Background One method to understand and evaluate an experiment that produces a large set of genes, such as a gene expression microarray analysis, is to identify overrepresentation or enrichment for biological pathways. Because pathways are able to functionally describe the set of genes, much effort has been made to collect curated biological pathways into publicly accessible databases. When combining disparate databases, highly related or redundant pathways exist, making their consolidation into pathway concepts essential. This will facilitate unbiased, comprehensive yet streamlined analysis of experiments that result in large gene sets. Methods After gene set enrichment finds representative pathways for large gene sets, pathways are consolidated into representative pathway concepts. Three complementary, but different methods of pathway consolidation are explored. Enrichment Consolidation combines the set of the pathways enriched for the signature gene list through iterative combining of enriched pathways with other pathways with similar signature gene sets; Weighted Consolidation utilizes a Protein-Protein Interaction network based gene-weighting approach that finds clusters of both enriched and non-enriched pathways limited to the experiments' resultant gene list; and finally the de novo Consolidation method uses several measurements of pathway similarity, that finds static pathway clusters independent of any given experiment. Results We demonstrate that the three consolidation methods provide unified yet different functional insights of a resultant gene set derived from a genome-wide profiling experiment. Results from the methods are presented, demonstrating their applications in biological studies and comparing with a pathway web-based framework that also combines several pathway databases. Additionally a web-based consolidation framework that encompasses all three methods discussed in this paper, Pathway Distiller (http://cbbiweb.uthscsa.edu/PathwayDistiller), is established to allow researchers access to the methods and example microarray data described in this manuscript, and the ability to analyze their own gene list by using our unique consolidation methods. Conclusions By combining several pathway systems, implementing different, but complementary pathway consolidation methods, and providing a user-friendly web-accessible tool, we have enabled users the ability to extract functional explanations of their genome wide experiments. PMID:23134636

Pathway Distiller - multisource biological pathway consolidation.

PubMed

Doderer, Mark S; Anguiano, Zachry; Suresh, Uthra; Dashnamoorthy, Ravi; Bishop, Alexander J R; Chen, Yidong

2012-01-01

One method to understand and evaluate an experiment that produces a large set of genes, such as a gene expression microarray analysis, is to identify overrepresentation or enrichment for biological pathways. Because pathways are able to functionally describe the set of genes, much effort has been made to collect curated biological pathways into publicly accessible databases. When combining disparate databases, highly related or redundant pathways exist, making their consolidation into pathway concepts essential. This will facilitate unbiased, comprehensive yet streamlined analysis of experiments that result in large gene sets. After gene set enrichment finds representative pathways for large gene sets, pathways are consolidated into representative pathway concepts. Three complementary, but different methods of pathway consolidation are explored. Enrichment Consolidation combines the set of the pathways enriched for the signature gene list through iterative combining of enriched pathways with other pathways with similar signature gene sets; Weighted Consolidation utilizes a Protein-Protein Interaction network based gene-weighting approach that finds clusters of both enriched and non-enriched pathways limited to the experiments' resultant gene list; and finally the de novo Consolidation method uses several measurements of pathway similarity, that finds static pathway clusters independent of any given experiment. We demonstrate that the three consolidation methods provide unified yet different functional insights of a resultant gene set derived from a genome-wide profiling experiment. Results from the methods are presented, demonstrating their applications in biological studies and comparing with a pathway web-based framework that also combines several pathway databases. Additionally a web-based consolidation framework that encompasses all three methods discussed in this paper, Pathway Distiller (http://cbbiweb.uthscsa.edu/PathwayDistiller), is established to allow researchers access to the methods and example microarray data described in this manuscript, and the ability to analyze their own gene list by using our unique consolidation methods. By combining several pathway systems, implementing different, but complementary pathway consolidation methods, and providing a user-friendly web-accessible tool, we have enabled users the ability to extract functional explanations of their genome wide experiments.

Formation and relaxation of quasistationary states in particle systems with power-law interactions

NASA Astrophysics Data System (ADS)

Marcos, B.; Gabrielli, A.; Joyce, M.

2017-09-01

We explore the formation and relaxation of the so-called quasistationary states (QSS) for particle distributions in three dimensions interacting via an attractive radial pair potential V (r →∞ ) ˜1 /rγ with γ >0 , and either a soft core or hard core regularization at small r . In the first part of the paper, we generalize, for any spatial dimension d ≥2 , Chandrasekhar's approach for the case of gravity to obtain analytic estimates of the rate of collisional relaxation due to two-body collisions. The resultant relaxation rates indicate an essential qualitative difference depending on the integrability of the pair force at large distances: for γ >d -1 , the rate diverges in the large particle number N (mean-field) limit, unless a sufficiently large soft core is present; for γ

Surface-enhanced Raman scattering on tunable plasmonic nanoparticle substrates

PubMed Central

Jackson, J. B.; Halas, N. J.

2004-01-01

Au and Ag nanoshells are investigated as substrates for surface-enhanced Raman scattering (SERS). We find that SERS enhancements on nanoshell films are dramatically different from those observed on colloidal aggregates, specifically that the Raman enhancement follows the plasmon resonance of the individual nanoparticles. Comparative finite difference time domain calculations of fields at the surface of smooth and roughened nanoshells reveal that surface roughness contributes only slightly to the total enhancement. SERS enhancements as large as 2.5 × 1010 on Ag nanoshell films for the nonresonant molecule p-mercaptoaniline are measured. PMID:15608058

Supersymmetry searches in GUT models with non-universal scalar masses

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

Cannoni, M.; Gómez, M.E.; Ellis, J.

2016-03-01

We study SO(10), SU(5) and flipped SU(5) GUT models with non-universal soft supersymmetry-breaking scalar masses, exploring how they are constrained by LHC supersymmetry searches and cold dark matter experiments, and how they can be probed and distinguished in future experiments. We find characteristic differences between the various GUT scenarios, particularly in the coannihilation region, which is very sensitive to changes of parameters. For example, the flipped SU(5) GUT predicts the possibility of ∼t{sub 1}−χ coannihilation, which is absent in the regions of the SO(10) and SU(5) GUT parameter spaces that we study. We use the relic density predictions in differentmore » models to determine upper bounds for the neutralino masses, and we find large differences between different GUT models in the sparticle spectra for the same LSP mass, leading to direct connections of distinctive possible experimental measurements with the structure of the GUT group. We find that future LHC searches for generic missing E{sub T}, charginos and stops will be able to constrain the different GUT models in complementary ways, as will the Xenon 1 ton and Darwin dark matter scattering experiments and future FERMI or CTA γ-ray searches.« less

Hippocampus and amygdala morphology in adults with attention-deficit hyperactivity disorder

PubMed Central

Perlov, Evgeniy; Philipsen, Alexandra; Tebartz van Elst, Ludger; Ebert, Dieter; Henning, Juergen; Maier, Simon; Bubl, Emanuel; Hesslinger, Bernd

2008-01-01

Objective Attention-deficit hyperactivity disorder (ADHD) in adulthood is a serious health problem with a prevalence of up to 4%. Limbic structures have been implicated in the genesis of ADHD; it has been suggested that they mediate mood and cognitive disturbances in affected individuals. Recently, a large study involving children and adolescents with ADHD reported bilateral enlargement of the hippocampus and indirect evidence of amygdala volume loss in this patient sample. We sought to test the hypothesis that, like in pediatric patients, there might be hippocampus and amygdala volume abnormalities in adult patients with ADHD. Methods We studied 27 adult patients with ADHD and 27 group-matched healthy volunteers using a 1.5 T magnetic resonance imaging scanner. We manually obtained morphometric measurements of the regions mentioned. Results In contrast to previous findings in children and adolescents, we found no significant differences in hippocampus and amygdala volumes among adults with and without the disorder. Conclusion Findings of hippocampus enlargement and amygdala volume loss are not very stable across different samples of patients with ADHD. Contradictory findings may be related to the different locations of alterations along the complex circuits responsible for the different symptoms of ADHD. Further studies involving larger samples of adult patients with ADHD and using multimodal designs are needed. PMID:18982173

Relationships between work environment factors and workers' well-being in the maritime industry.

PubMed

Nielsen, Morten Birkeland; Bergheim, Kjersti; Eid, Jarle

2013-01-01

The aim of this study was to determine whether physical and psychosocial work factors are related to the levels of job satisfaction and intentions to leave in the maritime industry, and to determine whether there exist cross-cultural differences in work factors, job satisfaction and intentions to leave between European and Filipino crew members. Using a cross-sectional survey design, the variables were assessed in a sample of 541 seafarers from 2 large Norwegian shipping companies. Work factors included safety perceptions,leadership, job demands, harassment, and team cohesion. The findings show that physical and psychosocial work factors are important correlates of both intentions to leave and job satisfaction, with safety perceptions, job demands, and team cohesion as the strongest and most consistent factors. As for cross-cultural differences, the findings show that European and Filipino respondents differ with regard to safety perceptions, laissez-faire leadership, authentic leadership,exposure to harassment, team cohesion, and intentions to leave. No differences were established with regard to overall job satisfaction. The findings support occupational stress models which emphasise the importance of situational factors in the understanding of well-being among workers. Shipping companies should therefore always take these factors into consideration when developing and implementing interventions aimed at improving employee well-being.

Integrative Analysis of Sex-Specific microRNA Networks Following Stress in Mouse Nucleus Accumbens.

PubMed

Pfau, Madeline L; Purushothaman, Immanuel; Feng, Jian; Golden, Sam A; Aleyasin, Hossein; Lorsch, Zachary S; Cates, Hannah M; Flanigan, Meghan E; Menard, Caroline; Heshmati, Mitra; Wang, Zichen; Ma'ayan, Avi; Shen, Li; Hodes, Georgia E; Russo, Scott J

2016-01-01

Adult women are twice as likely as men to suffer from affective and anxiety disorders, although the mechanisms underlying heightened female stress susceptibility are incompletely understood. Recent findings in mouse Nucleus Accumbens (NAc) suggest a role for DNA methylation-driven sex differences in genome-wide transcriptional profiles. However, the role of another epigenetic process-microRNA (miR) regulation-has yet to be explored. We exposed male and female mice to Subchronic Variable Stress (SCVS), a stress paradigm that produces depression-like behavior in female, but not male, mice, and performed next generation mRNA and miR sequencing on NAc tissue. We applied a combination of differential expression, miR-mRNA network and functional enrichment analyses to characterize the transcriptional and post-transcriptional landscape of sex differences in NAc stress response. We find that male and female mice exhibit largely non-overlapping miR and mRNA profiles following SCVS. The two sexes also show enrichment of different molecular pathways and functions. Collectively, our results suggest that males and females mount fundamentally different transcriptional and post-transcriptional responses to SCVS and engage sex-specific molecular processes following stress. These findings have implications for the pathophysiology and treatment of stress-related disorders in women.

CoCoNUT: an efficient system for the comparison and analysis of genomes

PubMed Central

2008-01-01

Background Comparative genomics is the analysis and comparison of genomes from different species. This area of research is driven by the large number of sequenced genomes and heavily relies on efficient algorithms and software to perform pairwise and multiple genome comparisons. Results Most of the software tools available are tailored for one specific task. In contrast, we have developed a novel system CoCoNUT (Computational Comparative geNomics Utility Toolkit) that allows solving several different tasks in a unified framework: (1) finding regions of high similarity among multiple genomic sequences and aligning them, (2) comparing two draft or multi-chromosomal genomes, (3) locating large segmental duplications in large genomic sequences, and (4) mapping cDNA/EST to genomic sequences. Conclusion CoCoNUT is competitive with other software tools w.r.t. the quality of the results. The use of state of the art algorithms and data structures allows CoCoNUT to solve comparative genomics tasks more efficiently than previous tools. With the improved user interface (including an interactive visualization component), CoCoNUT provides a unified, versatile, and easy-to-use software tool for large scale studies in comparative genomics. PMID:19014477

EASApprox® skin-stretching system: A secure and effective method to achieve wound closure.

PubMed

Song, Mingzhi; Zhang, Zhen; Liu, Tao; Liu, Song; Li, Gang; Liu, Zhaochang; Huang, Jingyang; Chen, Song; Li, Linan; Guo, Li; Qiu, Yang; Wan, Jiajia; Liu, Yuejian; Wu, Tao; Wang, Xiaoyong; Lu, Ming; Wang, Shouyu

2017-07-01

Large skin defects are commonly observed in the clinic and have attracted much attention recently. Therefore, finding an effective solution for large skin defects is a global problem. The objective of the present study was to assess the effectiveness of the EASApprox ® skin-stretching system for closing large skin defects. Skin defects (5×5 cm) were created on the forearms of 9 Bama miniature pigs, which were randomly divided into the following three groups: Direct suture, the new EASApprox ® skin-stretching device and Kirschner wires. Microcirculation was assessed before surgery and after wound closure. Following the different treatments, the defects were sutured, and wound healing was assessed based on a clinical score. Furthermore, microscopic and ultramicroscopic structures were evaluated, including collagen, elastic fibers and the microvessel density. Significant differences in the clinical score and microvessel density were observed among the groups. Additionally, the mean length obtained for elastic fibers was larger than that obtained for the other two groups. Finally, the new EASApprox ® skin-stretching device resulted in successful wound management and with only minor side effects on skin histology and microcirculation. Therefore, this method has the potential to be used for healing large skin defects.

Illusory expectations can affect retrieval-monitoring accuracy.

PubMed

McDonough, Ian M; Gallo, David A

2012-03-01

The present study investigated how expectations, even when illusory, can affect the accuracy of memory decisions. Participants studied words presented in large or small font for subsequent memory tests. Replicating prior work, judgments of learning indicated that participants expected to remember large words better than small words, even though memory for these words was equivalent on a standard test of recognition memory and subjective judgments. Critically, we also included tests that instructed participants to selectively search memory for either large or small words, thereby allowing different memorial expectations to contribute to performance. On these tests we found reduced false recognition when searching memory for large words relative to small words, such that the size illusion paradoxically affected accuracy measures (d' scores) in the absence of actual memory differences. Additional evidence for the role of illusory expectations was that (a) the accuracy effect was obtained only when participants searched memory for the aspect of the stimuli corresponding to illusory expectations (size instead of color) and (b) the accuracy effect was eliminated on a forced-choice test that prevented the influence of memorial expectations. These findings demonstrate the critical role of memorial expectations in the retrieval-monitoring process. 2012 APA, all rights reserved

Decompositions of large-scale biological systems based on dynamical properties.

PubMed

Soranzo, Nicola; Ramezani, Fahimeh; Iacono, Giovanni; Altafini, Claudio

2012-01-01

Given a large-scale biological network represented as an influence graph, in this article we investigate possible decompositions of the network aimed at highlighting specific dynamical properties. The first decomposition we study consists in finding a maximal directed acyclic subgraph of the network, which dynamically corresponds to searching for a maximal open-loop subsystem of the given system. Another dynamical property investigated is strong monotonicity. We propose two methods to deal with this property, both aimed at decomposing the system into strongly monotone subsystems, but with different structural characteristics: one method tends to produce a single large strongly monotone component, while the other typically generates a set of smaller disjoint strongly monotone subsystems. Original heuristics for the methods investigated are described in the article. altafini@sissa.it

`Not hard to sway': a case study of student engagement in two large engineering classes

NASA Astrophysics Data System (ADS)

Shekhar, Prateek; Borrego, Maura

2018-07-01

Although engineering education research has empirically validated the effectiveness of active learning in improving student learning over traditional lecture-based methods, the adoption of active learning in classrooms has been slow. One of the greatest reported barriers is student resistance towards engagement in active learning exercises. This paper argues that the level of student engagement in active learning classrooms is an interplay of social and physical classroom characteristics. Using classroom observations and instructor interviews, this study describes the influence of the interaction of student response systems and classroom layout on student engagement in two large active-learning-based engineering classrooms. The findings suggest that the use of different student response systems in combination with cluster-style seating arrangements can increase student engagement in large classrooms.

Personality in 100,000 Words: A large-scale analysis of personality and word use among bloggers

PubMed Central

Yarkoni, Tal

2010-01-01

Previous studies have found systematic associations between personality and individual differences in word use. Such studies have typically focused on broad associations between major personality domains and aggregate word categories, potentially masking more specific associations. Here I report the results of a large-scale analysis of personality and word use in a large sample of blogs (N=694). The size of the dataset enabled pervasive correlations with personality to be identified for a broad range of lexical variables, including both aggregate word categories and individual English words. The results replicated category-level findings from previous offline studies, identified numerous novel associations at both a categorical and single-word level, and underscored the value of complementary approaches to the study of personality and word use. PMID:20563301

Complex Genetics of Behavior: BXDs in the Automated Home-Cage.

PubMed

Loos, Maarten; Verhage, Matthijs; Spijker, Sabine; Smit, August B

2017-01-01

This chapter describes a use case for the genetic dissection and automated analysis of complex behavioral traits using the genetically diverse panel of BXD mouse recombinant inbred strains. Strains of the BXD resource differ widely in terms of gene and protein expression in the brain, as well as in their behavioral repertoire. A large mouse resource opens the possibility for gene finding studies underlying distinct behavioral phenotypes, however, such a resource poses a challenge in behavioral phenotyping. To address the specifics of large-scale screening we describe how to investigate: (1) how to assess mouse behavior systematically in addressing a large genetic cohort, (2) how to dissect automation-derived longitudinal mouse behavior into quantitative parameters, and (3) how to map these quantitative traits to the genome, deriving loci underlying aspects of behavior.

First evidence of an extensive Acheulean large cutting tool accumulation in Europe from Porto Maior (Galicia, Spain).

PubMed

Méndez-Quintas, E; Santonja, M; Pérez-González, A; Duval, M; Demuro, M; Arnold, L J

2018-02-15

We describe a European Acheulean site characterised by an extensive accumulation of large cutting tools (LCT). This type of Lower Paleolithic assemblage, with dense LCT accumulations, has only been found on the African continent and in the Near East until now. The identification of a site with large accumulations of LCTs favours the hypothesis of an African origin for the Acheulean of Southwest Europe. The lithic tool-bearing deposits date back to 293-205 thousand years ago. Our chronological findings confirm temporal overlap between sites with clear "African" Acheulean affinities and Early Middle Paleolithic sites found elsewhere in the region. These complex technological patterns could be consistent with the potential coexistence of different human species in south-western Europe during the Middle Pleistocene.

A prospective study of fetal head growth, autistic traits and autism spectrum disorder

PubMed Central

Blanken, Laura M. E.; Dass, Alena; Alvares, Gail; van der Ende, Jan; Schoemaker, Nikita K.; El Marroun, Hanan; Hickey, Martha; Pennell, Craig; White, Scott; Maybery, Murray T.; Dissanayake, Cheryl; Jaddoe, Vincent W. V.; Verhulst, Frank C.; Tiemeier, Henning; McIntosh, Will; Whitehouse, Andrew

2018-01-01

Altered trajectories of brain growth are often reported in Autism Spectrum Disorder (ASD), particularly during the first year of life. However, less is known about prenatal head growth trajectories, and no study has examined the relation with postnatal autistic symptom severity. The current study prospectively examined the association between fetal head growth and the spectrum of autistic symptom severity in two large population‐based cohorts, including a sample of individuals with clinically diagnosed ASD. This study included 3,820 children from two longitudinal prenatal cohorts in The Netherlands and Australia, comprising 60 individuals with a confirmed diagnosis of ASD. Latent growth curve models were used to examine the relationship between fetal head circumference measured at three different time points and autistic traits measured in postnatal life using either the Social Responsiveness Scale or the Autism‐Spectrum Quotient. While lower initial prenatal HC was weakly associated with increasing autistic traits in the Dutch cohort, this relationship was not observed in the Australian cohort, nor when the two cohorts were analysed together. No differences in prenatal head growth were found between individuals with ASD and controls. This large population‐based study identified no consistent association across two cohorts between prenatal head growth and postnatal autistic traits. Our mixed findings suggest that further research in this area is needed. Autism Res 2018, 11: 602–612. © 2018 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc. Lay Summary It is not known whether different patterns of postnatal brain growth in Autism Spectrum Disorder (ASD) also occurs prenatally. We examined fetal head growth and autistic symptoms in two large groups from The Netherlands and Australia. Lower initial prenatal head circumference was associated with autistic traits in the Dutch, but not the Australian, group. No differences in head growth were found in individuals with ASD and controls when the data was combined. Our mixed findings suggest that more research in this area is needed. PMID:29356450

Characterizing Listener Engagement with Popular Songs Using Large-Scale Music Discovery Data

PubMed Central

Kaneshiro, Blair; Ruan, Feng; Baker, Casey W.; Berger, Jonathan

2017-01-01

Music discovery in everyday situations has been facilitated in recent years by audio content recognition services such as Shazam. The widespread use of such services has produced a wealth of user data, specifying where and when a global audience takes action to learn more about music playing around them. Here, we analyze a large collection of Shazam queries of popular songs to study the relationship between the timing of queries and corresponding musical content. Our results reveal that the distribution of queries varies over the course of a song, and that salient musical events drive an increase in queries during a song. Furthermore, we find that the distribution of queries at the time of a song's release differs from the distribution following a song's peak and subsequent decline in popularity, possibly reflecting an evolution of user intent over the “life cycle” of a song. Finally, we derive insights into the data size needed to achieve consistent query distributions for individual songs. The combined findings of this study suggest that music discovery behavior, and other facets of the human experience of music, can be studied quantitatively using large-scale industrial data. PMID:28386241

Heart rate variability indicates emotional value during pro-social economic laboratory decisions with large external validity.

PubMed

Fooken, Jonas

2017-03-10

The present study investigates the external validity of emotional value measured in economic laboratory experiments by using a physiological indicator of stress, heart rate variability (HRV). While there is ample evidence supporting the external validity of economic experiments, there is little evidence comparing the magnitude of internal levels of emotional stress during decision making with external stress. The current study addresses this gap by comparing the magnitudes of decision stress experienced in the laboratory with the stress from outside the laboratory. To quantify a large change in HRV, measures observed in the laboratory during decision-making are compared to the difference between HRV during a university exam and other mental activity for the same individuals in and outside of the laboratory. The results outside the laboratory inform about the relevance of laboratory findings in terms of their relative magnitude. Results show that psychologically induced HRV changes observed in the laboratory, particularly in connection with social preferences, correspond to large effects outside. This underscores the external validity of laboratory findings and shows the magnitude of emotional value connected to pro-social economic decisions in the laboratory.

Ungulates rely less on visual cues, but more on adapting movement behaviour, when searching for forage.

PubMed

Venter, Jan A; Prins, Herbert H T; Mashanova, Alla; Slotow, Rob

2017-01-01

Finding suitable forage patches in a heterogeneous landscape, where patches change dynamically both spatially and temporally could be challenging to large herbivores, especially if they have no a priori knowledge of the location of the patches. We tested whether three large grazing herbivores with a variety of different traits improve their efficiency when foraging at a heterogeneous habitat patch scale by using visual cues to gain a priori knowledge about potential higher value foraging patches. For each species (zebra ( Equus burchelli ), red hartebeest ( Alcelaphus buselaphus subspecies camaa ) and eland ( Tragelaphus oryx )), we used step lengths and directionality of movement to infer whether they were using visual cues to find suitable forage patches at a habitat patch scale. Step lengths were significantly longer for all species when moving to non-visible patches than to visible patches, but all movements showed little directionality. Of the three species, zebra movements were the most directional. Red hartebeest had the shortest step lengths and zebra the longest. We conclude that these large grazing herbivores may not exclusively use visual cues when foraging at a habitat patch scale, but would rather adapt their movement behaviour, mainly step length, to the heterogeneity of the specific landscape.

Characterizing Listener Engagement with Popular Songs Using Large-Scale Music Discovery Data.

PubMed

Kaneshiro, Blair; Ruan, Feng; Baker, Casey W; Berger, Jonathan

2017-01-01

Music discovery in everyday situations has been facilitated in recent years by audio content recognition services such as Shazam. The widespread use of such services has produced a wealth of user data, specifying where and when a global audience takes action to learn more about music playing around them. Here, we analyze a large collection of Shazam queries of popular songs to study the relationship between the timing of queries and corresponding musical content. Our results reveal that the distribution of queries varies over the course of a song, and that salient musical events drive an increase in queries during a song. Furthermore, we find that the distribution of queries at the time of a song's release differs from the distribution following a song's peak and subsequent decline in popularity, possibly reflecting an evolution of user intent over the "life cycle" of a song. Finally, we derive insights into the data size needed to achieve consistent query distributions for individual songs. The combined findings of this study suggest that music discovery behavior, and other facets of the human experience of music, can be studied quantitatively using large-scale industrial data.

Using Large Diabetes Databases for Research.

PubMed

Wild, Sarah; Fischbacher, Colin; McKnight, John

2016-09-01

There are an increasing number of clinical, administrative and trial databases that can be used for research. These are particularly valuable if there are opportunities for linkage to other databases. This paper describes examples of the use of large diabetes databases for research. It reviews the advantages and disadvantages of using large diabetes databases for research and suggests solutions for some challenges. Large, high-quality databases offer potential sources of information for research at relatively low cost. Fundamental issues for using databases for research are the completeness of capture of cases within the population and time period of interest and accuracy of the diagnosis of diabetes and outcomes of interest. The extent to which people included in the database are representative should be considered if the database is not population based and there is the intention to extrapolate findings to the wider diabetes population. Information on key variables such as date of diagnosis or duration of diabetes may not be available at all, may be inaccurate or may contain a large amount of missing data. Information on key confounding factors is rarely available for the nondiabetic or general population limiting comparisons with the population of people with diabetes. However comparisons that allow for differences in distribution of important demographic factors may be feasible using data for the whole population or a matched cohort study design. In summary, diabetes databases can be used to address important research questions. Understanding the strengths and limitations of this approach is crucial to interpret the findings appropriately. © 2016 Diabetes Technology Society.

Climate, Water, and Human Health: Large Scale Hydroclimatic Controls in Forecasting Cholera Epidemics

NASA Astrophysics Data System (ADS)

Akanda, A. S.; Jutla, A. S.; Islam, S.

2009-12-01

Despite ravaging the continents through seven global pandemics in past centuries, the seasonal and interannual variability of cholera outbreaks remain a mystery. Previous studies have focused on the role of various environmental and climatic factors, but provided little or no predictive capability. Recent findings suggest a more prominent role of large scale hydroclimatic extremes - droughts and floods - and attempt to explain the seasonality and the unique dual cholera peaks in the Bengal Delta region of South Asia. We investigate the seasonal and interannual nature of cholera epidemiology in three geographically distinct locations within the region to identify the larger scale hydroclimatic controls that can set the ecological and environmental ‘stage’ for outbreaks and have significant memory on a seasonal scale. Here we show that two distinctly different, pre and post monsoon, cholera transmission mechanisms related to large scale climatic controls prevail in the region. An implication of our findings is that extreme climatic events such as prolonged droughts, record floods, and major cyclones may cause major disruption in the ecosystem and trigger large epidemics. We postulate that a quantitative understanding of the large-scale hydroclimatic controls and dominant processes with significant system memory will form the basis for forecasting such epidemic outbreaks. A multivariate regression method using these predictor variables to develop probabilistic forecasts of cholera outbreaks will be explored. Forecasts from such a system with a seasonal lead-time are likely to have measurable impact on early cholera detection and prevention efforts in endemic regions.

Long-wavelength fluctuations and the glass transition in two dimensions and three dimensions

PubMed Central

Vivek, Skanda; Kelleher, Colm P.; Chaikin, Paul M.

2017-01-01

Phase transitions significantly differ between 2D and 3D systems, but the influence of dimensionality on the glass transition is unresolved. We use microscopy to study colloidal systems as they approach their glass transitions at high concentrations and find differences between two dimensions and three dimensions. We find that, in two dimensions, particles can undergo large displacements without changing their position relative to their neighbors, in contrast with three dimensions. This is related to Mermin–Wagner long-wavelength fluctuations that influence phase transitions in two dimensions. However, when measuring particle motion only relative to their neighbors, two dimensions and three dimensions have similar behavior as the glass transition is approached, showing that the long-wavelength fluctuations do not cause a fundamental distinction between 2D and 3D glass transitions. PMID:28137847

Long-wavelength fluctuations and the glass transition in two dimensions and three dimensions.

PubMed

Vivek, Skanda; Kelleher, Colm P; Chaikin, Paul M; Weeks, Eric R

2017-02-21

Phase transitions significantly differ between 2D and 3D systems, but the influence of dimensionality on the glass transition is unresolved. We use microscopy to study colloidal systems as they approach their glass transitions at high concentrations and find differences between two dimensions and three dimensions. We find that, in two dimensions, particles can undergo large displacements without changing their position relative to their neighbors, in contrast with three dimensions. This is related to Mermin-Wagner long-wavelength fluctuations that influence phase transitions in two dimensions. However, when measuring particle motion only relative to their neighbors, two dimensions and three dimensions have similar behavior as the glass transition is approached, showing that the long-wavelength fluctuations do not cause a fundamental distinction between 2D and 3D glass transitions.

Effects of Ensemble Configuration on Estimates of Regional Climate Uncertainties

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

Goldenson, N.; Mauger, G.; Leung, L. R.

Internal variability in the climate system can contribute substantial uncertainty in climate projections, particularly at regional scales. Internal variability can be quantified using large ensembles of simulations that are identical but for perturbed initial conditions. Here we compare methods for quantifying internal variability. Our study region spans the west coast of North America, which is strongly influenced by El Niño and other large-scale dynamics through their contribution to large-scale internal variability. Using a statistical framework to simultaneously account for multiple sources of uncertainty, we find that internal variability can be quantified consistently using a large ensemble or an ensemble ofmore » opportunity that includes small ensembles from multiple models and climate scenarios. The latter also produce estimates of uncertainty due to model differences. We conclude that projection uncertainties are best assessed using small single-model ensembles from as many model-scenario pairings as computationally feasible, which has implications for ensemble design in large modeling efforts.« less

High-sensitivity and large-dynamic-range refractive index sensors employing weak composite Fabry-Perot cavities.

PubMed

Chen, Pengcheng; Shu, Xuewen; Cao, Haoran; Sugden, Kate

2017-08-15

Most sensors face a common trade-off between high sensitivity and a large dynamic range. We demonstrate here an all-fiber refractometer based on a dual-cavity Fabry-Perot interferometer (FPI) that possesses the advantage of both high sensitivity and a large dynamic range. Since the two composite cavities have a large cavity length difference, one can observe both fine and coarse fringes, which correspond to the long cavity and the short cavity, respectively. The short-cavity FPI and the use of an intensity demodulation method mean that the individual fine fringe dips correspond to a series of quasi-continuous highly sensitive zones for refractive index measurement. By calculating the parameters of the composite FPI, we find that the range of the ultra-sensitive zones can be considerably adjusted to suit the end requirements. The experimental trends are in good agreement with the theoretical predictions. The co-existence of high sensitivity and a large dynamic range in a composite FPI is of great significance to practical RI measurements.

Personality Assessment Inventory scale characteristics and factor structure in the assessment of alcohol dependency.

PubMed

Schinka, J A

1995-02-01

Individual scale characteristics and the inventory structure of the Personality Assessment Inventory (PAI; Morey, 1991) were examined by conducting internal consistency and factor analyses of item and scale score data from a large group (N = 301) of alcohol-dependent patients. Alpha coefficients, mean inter-item correlations, and corrected item-total scale correlations for the sample paralleled values reported by Morey for a large clinical sample. Minor differences in the scale factor structure of the inventory from Morey's clinical sample were found. Overall, the findings support the use of the PAI in the assessment of personality and psychopathology of alcohol-dependent patients.

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

George, Damien P.; Mooij, Sander; Postma, Marieke, E-mail: dpg39@cam.ac.uk, E-mail: sander.mooij@ing.uchile.cl, E-mail: mpostma@nikhef.nl

We compute the one-loop renormalization group equations for Standard Model Higgs inflation. The calculation is done in the Einstein frame, using a covariant formalism for the multi-field system. All counterterms, and thus the betafunctions, can be extracted from the radiative corrections to the two-point functions; the calculation of higher n-point functions then serves as a consistency check of the approach. We find that the theory is renormalizable in the effective field theory sense in the small, mid and large field regime. In the large field regime our results differ slightly from those found in the literature, due to a differentmore » treatment of the Goldstone bosons.« less

The timescales of global surface-ocean connectivity.

PubMed

Jönsson, Bror F; Watson, James R

2016-04-19

Planktonic communities are shaped through a balance of local evolutionary adaptation and ecological succession driven in large part by migration. The timescales over which these processes operate are still largely unresolved. Here we use Lagrangian particle tracking and network theory to quantify the timescale over which surface currents connect different regions of the global ocean. We find that the fastest path between two patches--each randomly located anywhere in the surface ocean--is, on average, less than a decade. These results suggest that marine planktonic communities may keep pace with climate change--increasing temperatures, ocean acidification and changes in stratification over decadal timescales--through the advection of resilient types.

Dynamics of Polydisperse Foam-like Emulsion

NASA Astrophysics Data System (ADS)

Hicock, Harry; Feitosa, Klebert

2011-10-01

Foam is a complex fluid whose relaxation properties are associated with the continuous diffusion of gas from small to large bubbles driven by differences in Laplace pressures. We study the dynamics of bubble rearrangements by tracking droplets of a clear, buoyantly neutral emulsion that coarsens like a foam. The droplets are imaged in three dimensions using confocal microscopy. Analysis of the images allows us to measure their positions and radii, and track their evolution in time. We find that the droplet size distribution fits a Weibull distribution characteristics of foam systems. Additionally, we observe that droplets undergo continuous evolution interspersed by occasional large rearrangements in par with local relaxation behavior typical of foams.

The timescales of global surface-ocean connectivity

PubMed Central

Jönsson, Bror F.; Watson, James R.

2016-01-01

Planktonic communities are shaped through a balance of local evolutionary adaptation and ecological succession driven in large part by migration. The timescales over which these processes operate are still largely unresolved. Here we use Lagrangian particle tracking and network theory to quantify the timescale over which surface currents connect different regions of the global ocean. We find that the fastest path between two patches—each randomly located anywhere in the surface ocean—is, on average, less than a decade. These results suggest that marine planktonic communities may keep pace with climate change—increasing temperatures, ocean acidification and changes in stratification over decadal timescales—through the advection of resilient types. PMID:27093522

Using a Large Scale Computational Model to Study the Effect of Longitudinal and Radial Electrical Coupling in the Cochlea

NASA Astrophysics Data System (ADS)

Mistrík, Pavel; Ashmore, Jonathan

2009-02-01

We describe a large scale computational model of electrical current flow in the cochlea which is constructed by a flexible Modified Nodal Analysis algorithm to incorporate electrical components representing hair cells and the intercellular radial and longitudinal current flow. The model is used as a laboratory to study the effects of changing longitudinal gap junctional coupling, and shows the way in which cochlear microphonic spreads and tuning is affected. The process for incorporating mechanical longitudinal coupling and feedback is described. We find a difference in tuning and attenuation depending on whether longitudinal or radial couplings are altered.

Finding Groups in Gene Expression Data

PubMed Central

2005-01-01

The vast potential of the genomic insight offered by microarray technologies has led to their widespread use since they were introduced a decade ago. Application areas include gene function discovery, disease diagnosis, and inferring regulatory networks. Microarray experiments enable large-scale, high-throughput investigations of gene activity and have thus provided the data analyst with a distinctive, high-dimensional field of study. Many questions in this field relate to finding subgroups of data profiles which are very similar. A popular type of exploratory tool for finding subgroups is cluster analysis, and many different flavors of algorithms have been used and indeed tailored for microarray data. Cluster analysis, however, implies a partitioning of the entire data set, and this does not always match the objective. Sometimes pattern discovery or bump hunting tools are more appropriate. This paper reviews these various tools for finding interesting subgroups. PMID:16046827

Framing 'fracking': Exploring public perceptions of hydraulic fracturing in the United Kingdom.

PubMed

Williams, Laurence; Macnaghten, Phil; Davies, Richard; Curtis, Sarah

2015-07-13

The prospect of fracking in the United Kingdom has been accompanied by significant public unease. We outline how the policy debate is being framed by UK institutional actors, finding evidence of a dominant discourse in which the policy approach is defined through a deficit model of public understanding of science and in which a technical approach to feasibility and safety is deemed as sufficient grounds for good policymaking. Deploying a deliberative focus group methodology with lay publics across different sites in the north of England, we find that these institutional framings are poorly aligned with participants' responses. We find that unease regularly overflows the focus on safety and feasibility and cannot be satisfactorily explained by a lack of understanding on the part of participants. We find that scholarship from science and technology studies productively elucidates our participants' largely sceptical positions, and orientates strategies for responding to them more effectively. © The Author(s) 2015.

Framing ‘fracking’: Exploring public perceptions of hydraulic fracturing in the United Kingdom

PubMed Central

Williams, Laurence; Macnaghten, Phil; Davies, Richard; Curtis, Sarah

2015-01-01

The prospect of fracking in the United Kingdom has been accompanied by significant public unease. We outline how the policy debate is being framed by UK institutional actors, finding evidence of a dominant discourse in which the policy approach is defined through a deficit model of public understanding of science and in which a technical approach to feasibility and safety is deemed as sufficient grounds for good policymaking. Deploying a deliberative focus group methodology with lay publics across different sites in the north of England, we find that these institutional framings are poorly aligned with participants’ responses. We find that unease regularly overflows the focus on safety and feasibility and cannot be satisfactorily explained by a lack of understanding on the part of participants. We find that scholarship from science and technology studies productively elucidates our participants’ largely sceptical positions, and orientates strategies for responding to them more effectively. PMID:26170264

Anisotropic in-plane thermal conductivity in multilayer silicene

NASA Astrophysics Data System (ADS)

Zhou, Yang; Guo, Zhi-Xin; Chen, Shi-You; Xiang, Hong-Jun; Gong, Xin-Gao

2018-06-01

We systematically study thermal conductivity of multilayer silicene by means of Boltzmann Transportation Equation (BTE) method. We find that their thermal conductivity strongly depends on the surface structures. Thermal conductivity of bilayer silicene varies from 3.31 W/mK to 57.9 W/mK with different surface structures. Also, the 2 × 1 surface reconstruction induces unusual large thermal conductivity anisotropy, which reaches 70% in a four-layer silicene. We also find that the anisotropy decreases with silicene thickness increasing, owing to the significant reduction of thermal conductivity in the zigzag direction and its slight increment in the armchair direction. Finally, we find that both the phonon-lifetime anisotropy and the phonon-group-velocity anisotropy contribute to the thermal conductivity anisotropy of multilayer silicene. These findings could be helpful in the field of heat management, thermoelectric applications involving silicene and other multilayer nanomaterials with surface reconstructions in the future.

Quantum spin chains with multiple dynamics

NASA Astrophysics Data System (ADS)

Chen, Xiao; Fradkin, Eduardo; Witczak-Krempa, William

2017-11-01

Many-body systems with multiple emergent time scales arise in various contexts, including classical critical systems, correlated quantum materials, and ultracold atoms. We investigate such nontrivial quantum dynamics in a different setting: a spin-1 bilinear-biquadratic chain. It has a solvable entangled ground state, but a gapless excitation spectrum that is poorly understood. By using large-scale density matrix renormalization group simulations, we find that the lowest excitations have a dynamical exponent z that varies from 2 to 3.2 as we vary a coupling in the Hamiltonian. We find an additional gapless mode with a continuously varying exponent 2 ≤z <2.7 , which establishes the presence of multiple dynamics. In order to explain these striking properties, we construct a continuum wave function for the ground state, which correctly describes the correlations and entanglement properties. We also give a continuum parent Hamiltonian, but show that additional ingredients are needed to capture the excitations of the chain. By using an exact mapping to the nonequilibrium dynamics of a classical spin chain, we find that the large dynamical exponent is due to subdiffusive spin motion. Finally, we discuss the connections to other spin chains and to a family of quantum critical models in two dimensions.

Efficient hit-finding approaches for histone methyltransferases: the key parameters.

PubMed

Ahrens, Thomas; Bergner, Andreas; Sheppard, David; Hafenbradl, Doris

2012-01-01

For many novel epigenetics targets the chemical ligand space and structural information were limited until recently and are still largely unknown for some targets. Hit-finding campaigns are therefore dependent on large and chemically diverse libraries. In the specific case of the histone methyltransferase G9a, the authors have been able to apply an efficient process of intelligent selection of compounds for primary screening, rather than screening the full diverse deck of 900 000 compounds to identify hit compounds. A number of different virtual screening methods have been applied for the compound selection, and the results have been analyzed in the context of their individual success rates. For the primary screening of 2112 compounds, a FlashPlate assay format and full-length histone H3.1 substrate were employed. Validation of hit compounds was performed using the orthogonal fluorescence lifetime technology. Rated by purity and IC(50) value, 18 compounds (0.9% of compound screening deck) were finally considered validated primary G9a hits. The hit-finding approach has led to novel chemotypes being identified, which can facilitate hit-to-lead projects. This study demonstrates the power of virtual screening technologies for novel, therapeutically relevant epigenetics protein targets.

Retainment of r-process material in dwarf galaxies

NASA Astrophysics Data System (ADS)

Beniamini, Paz; Dvorkin, Irina; Silk, Joe

2018-04-01

The synthesis of r-process elements is known to involve extremely energetic explosions. At the same time, recent observations find significant r-process enrichment even in extremely small ultra-faint dwarf (UFD) galaxies. This raises the question of retainment of those elements within their hosts. We estimate the retainment fraction and find that it is large ˜0.9, unless the r-process event is very energetic (≳ 1052erg) and / or the host has lost a large fraction of its gas prior to the event. We estimate the r-process mass per event and rate as implied by abundances in UFDs, taking into account imperfect retainment and different models of UFD evolution. The results are consistent with previous estimates (Beniamini et al. 2016b) and with the constraints from the recently detected macronova accompanying a neutron star merger (GW170817). We also estimate the distribution of abundances predicted by these models. We find that ˜0.07 of UFDs should have r-process enrichment. The results are consistent with both the mean values and the fluctuations of [Eu/Fe] in galactic metal poor stars, supporting the possibility that UFDs are the main 'building blocks' of the galactic halo population.

The relationship between neuroticism, major depressive disorder and comorbid disorders in Chinese women

PubMed Central

Xia, Jing; He, Qiang; Li, Yihan; Xie, Dong; Zhu, Suoyu; Chen, Jing; Shen, Yuan; Zhang, Ning; Wei, Yan; Chen, Chunfeng; Shen, Jianhua; Zhang, Yan; Gao, Chengge; Li, Youhui; Ding, Jihong; Shen, Wenwu; Wang, Qian; Cao, Meiyue; Liu, Tiebang; Zhang, Jinbei; Duan, Huijun; Bao, Cheng; Ma, Ping; Zhou, Cong; Luo, Yanfang; Zhang, Fengzhi; Liu, Ying; Li, Yi; Jin, Guixing; Zhang, Yutang; Liang, Wei; Chen, Yunchun; Zhao, Changyin; Li, Haiyan; Chen, Yiping; Shi, Shenxun; Kendler, Kenneth S.; Flint, Jonathan; Wang, Xumei

2011-01-01

Objective The personality trait of neuroticism is a risk factor for major depressive disorder (MDD), but this relationship has not been demonstrated in clinical samples from Asia. Methods We examined a large-scale clinical study of Chinese Han women with recurrent major depression and community-acquired controls. Results Elevated levels of neuroticism increased the risk for lifetime MDD (with an odds ratio of 1.37 per SD), contributed to the comorbidity of MDD with anxiety disorders, and predicted the onset and severity of MDD. Our findings largely replicate those obtained in clinical populations in Europe and US but differ in two ways: we did not find a relationship between melancholia and neuroticism; we found lower mean scores for neuroticism (3.6 in our community control sample). Limitations Our findings do not apply to MDD in community-acquired samples and may be limited to Han Chinese women. It is not possible to determine whether the association between neuroticism and MDD reflects a causal relationship. Conclusions Neuroticism acts as a risk factor for MDD in Chinese women, as it does in the West and may particularly predispose to comorbidity with anxiety disorders. Cultural factors may have an important effect on its measurement. PMID:21824661

Personality Trait Differences Between Young and Middle-Aged Adults: Measurement Artifacts or Actual Trends?

PubMed

Nye, Christopher D; Allemand, Mathias; Gosling, Samuel D; Potter, Jeff; Roberts, Brent W

2016-08-01

A growing body of research demonstrates that older individuals tend to score differently on personality measures than younger adults. However, recent research using item response theory (IRT) has questioned these findings, suggesting that apparent age differences in personality traits merely reflect artifacts of the response process rather than true differences in the latent constructs. Conversely, other studies have found the opposite-age differences appear to be true differences rather than response artifacts. Given these contradictory findings, the goal of the present study was to examine the measurement equivalence of personality ratings drawn from large groups of young and middle-aged adults (a) to examine whether age differences in personality traits could be completely explained by measurement nonequivalence and (b) to illustrate the comparability of IRT and confirmatory factor analysis approaches to testing equivalence in this context. Self-ratings of personality traits were analyzed in two groups of Internet respondents aged 20 and 50 (n = 15,726 in each age group). Measurement nonequivalence across these groups was negligible. The effect sizes of the mean differences due to nonequivalence ranged from -.16 to .15. Results indicate that personality trait differences across age groups reflect actual differences rather than merely response artifacts. © 2015 Wiley Periodicals, Inc.

An assessment of the direction-finding accuracy of bat biosonar beampatterns.

PubMed

Gilani, Uzair S; Müller, Rolf

2016-02-01

In the biosonar systems of bats, emitted acoustic energy and receiver sensitivity are distributed over direction and frequency through beampattern functions that have diverse and often complicated geometries. This complexity could be used by the animals to determine the direction of incoming sounds based on spectral signatures. The present study has investigated how well bat biosonar beampatterns are suited for direction finding using a measure of the smallest estimator variance that is possible for a given direction [Cramér-Rao lower bound (CRLB)]. CRLB values were estimated for numerical beampattern estimates derived from 330 individual shape samples, 157 noseleaves (used for emission), and 173 outer ears (pinnae). At an assumed 60 dB signal-to-noise ratio, the average value of the CRLB was 3.9°, which is similar to previous behavioral findings. Distribution for the CRLBs in individual beampatterns had a positive skew indicating the existence of regions where a given beampattern does not support a high accuracy. The highest supported accuracies were for direction finding in elevation (with the exception of phyllostomid emission patterns). No large, obvious differences in the CRLB (greater 2° in the mean) were found between the investigated major taxonomic groups, suggesting that different bat species have access to similar direction-finding information.

Attitudes toward pharmacological cognitive enhancement—a review

PubMed Central

Schelle, Kimberly J.; Faulmüller, Nadira; Caviola, Lucius; Hewstone, Miles

2014-01-01

A primary means for the augmentation of cognitive brain functions is “pharmacological cognitive enhancement” (PCE). The term usually refers to the off-label use of medical substances to improve mental performance in healthy individuals. With the final aim to advance the normative debate taking place on that topic, several empirical studies have been conducted to assess the attitudes toward PCE in the public, i.e., in groups outside of the academic debate. In this review, we provide an overview of the 40 empirical studies published so far, reporting both their methodology and results. Overall, we find that several concerns about the use of PCE are prevalent in the public. These concerns largely match those discussed in the normative academic debate. We present our findings structured around the three most common concerns: medical safety, coercion, and fairness. Fairness is divided into three subthemes: equality of opportunity, honesty, and authenticity. Attitudes regarding some concerns are coherent across studies (e.g., coercion), whereas for others we find mixed results (e.g., authenticity). Moreover, we find differences in how specific groups—such as users, nonusers, students, parents, and health care providers—perceive PCE: a coherent finding is that nonusers display more concerns regarding medical safety and fairness than users. We discuss potential psychological explanations for these differences. PMID:24860438

Younger and older adults' associative memory for social information: The role of information importance.

PubMed

Hargis, Mary B; Castel, Alan D

2017-06-01

The ability to associate items in memory is critical for social interactions. Older adults show deficits in remembering associative information but can sometimes remember high-value information. In two experiments, younger and older participants studied faces, names, and occupations that were of differing social value. There were no age differences in the recall of important information in Experiment 1, but age differences were present for less important information. In Experiment 2, when younger adults' encoding time was reduced, age differences were largely absent. These findings are considered in light of value-directed strategies when remembering social associative information. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Multimodal neuroimaging of male and female brain structure in health and disease across the life span.

PubMed

Jahanshad, Neda; Thompson, Paul M

2017-01-02

Sex differences in brain development and aging are important to identify, as they may help to understand risk factors and outcomes in brain disorders that are more prevalent in one sex compared with the other. Brain imaging techniques have advanced rapidly in recent years, yielding detailed structural and functional maps of the living brain. Even so, studies are often limited in sample size, and inconsistent findings emerge, one example being varying findings regarding sex differences in the size of the corpus callosum. More recently, large-scale neuroimaging consortia such as the Enhancing Neuro Imaging Genetics through Meta Analysis Consortium have formed, pooling together expertise, data, and resources from hundreds of institutions around the world to ensure adequate power and reproducibility. These initiatives are helping us to better understand how brain structure is affected by development, disease, and potential modulators of these effects, including sex. This review highlights some established and disputed sex differences in brain structure across the life span, as well as pitfalls related to interpreting sex differences in health and disease. We also describe sex-related findings from the ENIGMA consortium, and ongoing efforts to better understand sex differences in brain circuitry. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.

Affective traits link to reliable neural markers of incentive anticipation.

PubMed

Wu, Charlene C; Samanez-Larkin, Gregory R; Katovich, Kiefer; Knutson, Brian

2014-01-01

While theorists have speculated that different affective traits are linked to reliable brain activity during anticipation of gains and losses, few have directly tested this prediction. We examined these associations in a community sample of healthy human adults (n=52) as they played a Monetary Incentive Delay task while undergoing functional magnetic resonance imaging (FMRI). Factor analysis of personality measures revealed that subjects independently varied in trait Positive Arousal and trait Negative Arousal. In a subsample (n=14) retested over 2.5years later, left nucleus accumbens (NAcc) activity during anticipation of large gains (+$5.00) and right anterior insula activity during anticipation of large losses (-$5.00) showed significant test-retest reliability (intraclass correlations>0.50, p's<0.01). In the full sample (n=52), trait Positive Arousal correlated with individual differences in left NAcc activity during anticipation of large gains, while trait Negative Arousal correlated with individual differences in right anterior insula activity during anticipation of large losses. Associations of affective traits with neural activity were not attributable to the influence of other potential confounds (including sex, age, wealth, and motion). Together, these results demonstrate selective links between distinct affective traits and reliably-elicited activity in neural circuits associated with anticipation of gain versus loss. The findings thus reveal neural markers for affective dimensions of healthy personality, and potentially for related psychiatric symptoms. © 2013. Published by Elsevier Inc. All rights reserved.

Affective traits link to reliable neural markers of incentive anticipation

PubMed Central

Wu, Charlene C.; Samanez-Larkin, Gregory R.; Katovich, Kiefer; Knutson, Brian

2013-01-01

While theorists have speculated that different affective traits are linked to reliable brain activity during anticipation of gains and losses, few have directly tested this prediction. We examined these associations in a community sample of healthy human adults (n = 52) as they played a Monetary Incentive Delay Task while undergoing functional magnetic resonance imaging (FMRI). Factor analysis of personality measures revealed that subjects independently varied in trait Positive Arousal and Negative Arousal. In a subsample (n = 14) retested over 2.5 years later, left nucleus accumbens (NAcc) activity during anticipation of large gains (+$5.00) and right anterior insula activity during anticipation of large losses (−$5.00) showed significant test-retest reliability (intraclass correlations > 0.50, p’s < 0.01). In the full sample (n = 52), trait Positive Arousal correlated with individual differences in left NAcc activity during anticipation of large gains, while trait Negative Arousal correlated with individual differences in right anterior insula activity during anticipation of large losses. Associations of affective traits with neural activity were not attributable to the influence of other potential confounds (including sex, age, wealth, and motion). Together, these results demonstrate selective links between distinct affective traits and reliably-elicited activity in neural circuits associated with anticipation of gain versus loss. The findings thus reveal neural markers for affective dimensions of healthy personality, and potentially for related psychiatric symptoms. PMID:24001457

Between-Site Differences in the Scale of Dispersal and Gene Flow in Red Oak

PubMed Central

Moran, Emily V.; Clark, James S.

2012-01-01

Background Nut-bearing trees, including oaks (Quercus spp.), are considered to be highly dispersal limited, leading to concerns about their ability to colonize new sites or migrate in response to climate change. However, estimating seed dispersal is challenging in species that are secondarily dispersed by animals, and differences in disperser abundance or behavior could lead to large spatio-temporal variation in dispersal ability. Parentage and dispersal analyses combining genetic and ecological data provide accurate estimates of current dispersal, while spatial genetic structure (SGS) can shed light on past patterns of dispersal and establishment. Methodology and Principal Findings In this study, we estimate seed and pollen dispersal and parentage for two mixed-species red oak populations using a hierarchical Bayesian approach. We compare these results to those of a genetic ML parentage model. We also test whether observed patterns of SGS in three size cohorts are consistent with known site history and current dispersal patterns. We find that, while pollen dispersal is extensive at both sites, the scale of seed dispersal differs substantially. Parentage results differ between models due to additional data included in Bayesian model and differing genotyping error assumptions, but both indicate between-site dispersal differences. Patterns of SGS in large adults, small adults, and seedlings are consistent with known site history (farmed vs. selectively harvested), and with long-term differences in seed dispersal. This difference is consistent with predator/disperser satiation due to higher acorn production at the low-dispersal site. While this site-to-site variation results in substantial differences in asymptotic spread rates, dispersal for both sites is substantially lower than required to track latitudinal temperature shifts. Conclusions Animal-dispersed trees can exhibit considerable spatial variation in seed dispersal, although patterns may be surprisingly constant over time. However, even under favorable conditions, migration in heavy-seeded species is likely to lag contemporary climate change. PMID:22563504

Using machine learning for improving knowledge on antibacterial effect of bioactive glass.

PubMed

Echezarreta-López, M M; Landin, M

2013-09-10

The aim of this work was to find relationships between critical bioactive glass characteristics and their antibacterial behaviour using an artificial intelligence tool. A large dataset including ingredients and process variables of the bioactive glasses production, bacterial characteristics and microbiological experimental conditions was generated from literature and analyzed by neurofuzzy logic technology. Our findings allow an explanation on the variability in antibacterial behaviour found by different authors and to obtain general conclusions about critical parameters of bioactive glasses to be considered in order to achieve activity against some of the most common skin and implant surgery pathogens. Copyright © 2013 Elsevier B.V. All rights reserved.

The ENCODE project: implications for psychiatric genetics.

PubMed

Kavanagh, D H; Dwyer, S; O'Donovan, M C; Owen, M J

2013-05-01

The ENCyclopedia Of DNA Elements (ENCODE) project is a public research consortium that aims to identify all functional elements of the human genome sequence. The project comprised 1640 data sets, from 147 different cell type and the findings were released in a coordinated set of 34 publications across several journals. The ENCODE publications report that 80.4% of the human genome displays some functionality. These data have important implications for interpreting results from large-scale genetics studies. We reviewed some of the key findings from the ENCODE publications and discuss how they can influence or inform further investigations into the genetic factors contributing to neuropsychiatric disorders.

Age, wage, and job placement: older women's experiences entering the retail sector.

PubMed

Frank-Miller, Ellen G; Lambert, Susan J; Henly, Julia R

2015-01-01

Older women seeking employment often find opportunities limited to low-wage jobs, such as those in retail. We report findings about job placement and starting wages for hourly workers hired at a women's apparel retailer from August 2006 to December 2009. We examine competing hypotheses regarding the role of age in explaining women's job placement and starting wages. Although newly hired women age 55+ earn higher wages and are placed in higher-quality jobs than the youngest women (ages 18-22), they are less likely to be placed in better-quality jobs than their midlife counterparts. Overall, wage differences are largely explained by job quality.

Social Cognitive Mediators of Sociodemographic Differences in Colorectal Cancer Screening Uptake

PubMed Central

Lo, Siu Hing; Waller, Jo; Vrinten, Charlotte; Kobayashi, Lindsay; von Wagner, Christian

2015-01-01

Background. This study examined if and how sociodemographic differences in colorectal cancer (CRC) screening uptake can be explained by social cognitive factors. Methods. Face-to-face interviews were conducted with individuals aged 60–70 years (n = 1309) living in England as part of a population-based omnibus survey. Results. There were differences in screening uptake by SES, marital status, ethnicity, and age but not by gender. Perceived barriers (stand. b = −0.40, p < 0.001), social norms (stand. b = 0.33, p < 0.001), and screening knowledge (stand. b = 0.17, p < 0.001) had independent associations with uptake. SES differences in uptake were mediated through knowledge, social norms, and perceived barriers. Ethnic differences were mediated through knowledge. Differences in uptake by marital status were primarily mediated through social norms and to a lesser extent through knowledge. Age differences were largely unmediated, except for a small mediated effect via social norms. Conclusions. Sociodemographic differences in CRC screening uptake were largely mediated through social cognitive factors. Impact. Our findings suggest that multifaceted interventions might be needed to reduce socioeconomic inequalities. Ethnic differences might be reduced through improved screening knowledge. Normative interventions could emphasise screening as an activity endorsed by important others outside the immediate family to appeal to a wider audience. PMID:26504782

Gender Differences in Cognition in China and Reasons for Change over Time: Evidence from CHARLS.

PubMed

Lei, Xiaoyan; Smith, James P; Sun, Xiaoting; Zhao, Yaohui

2014-12-01

In this paper, we model gender differences in cognitive ability in China using a new sample of middle-aged and older Chinese respondents. Modeled after the American Health and Retirement Survey (HRS), CHARLS respondents are 45 years and older and are nationally representative of the Chinese population in this age span. Our measures of cognition in CHARLS rely on two measures that proxy for different dimensions of adult cognition-episodic memory and intact mental status. We relate these cognitive measures to adult health and SES outcomes during the adult years. We find large cognitive differences to the detriment of women that were mitigated by large gender differences in education among these generations of Chinese people. These gender differences in cognition are especially concentrated in the older age groups and poorer communities within the sample. We also investigated historical, geographical, and cultural characteristics of communities to understand how they impact cognition. Economic development and environmental improvement such as having electricity, increases in wage per capita and green coverage ratio generally contribute to higher cognition ability. Women benefit more from the fruits of development -electricity and growth of green coverage ratio are conducive to lessening female disadvantage in cognition.

Gender Differences in Cognition in China and Reasons for Change over Time: Evidence from CHARLS

PubMed Central

Lei, Xiaoyan; Sun, Xiaoting; Zhao, Yaohui

2014-01-01

In this paper, we model gender differences in cognitive ability in China using a new sample of middle-aged and older Chinese respondents. Modeled after the American Health and Retirement Survey (HRS), CHARLS respondents are 45 years and older and are nationally representative of the Chinese population in this age span. Our measures of cognition in CHARLS rely on two measures that proxy for different dimensions of adult cognition—episodic memory and intact mental status. We relate these cognitive measures to adult health and SES outcomes during the adult years. We find large cognitive differences to the detriment of women that were mitigated by large gender differences in education among these generations of Chinese people. These gender differences in cognition are especially concentrated in the older age groups and poorer communities within the sample. We also investigated historical, geographical, and cultural characteristics of communities to understand how they impact cognition. Economic development and environmental improvement such as having electricity, increases in wage per capita and green coverage ratio generally contribute to higher cognition ability. Women benefit more from the fruits of development –electricity and growth of green coverage ratio are conducive to lessening female disadvantage in cognition. PMID:25530942

Office type's association to employees' welfare: Three studies.

PubMed

Danielsson, Christina Bodin

2016-08-12

The workplace is important for employees' daily life and well-being. This article investigates exploratory the office design's role for employees' welfare from different perspectives. By comparing different studies of the office, type's influence on different factors of employees' welfare the aim is to see if any common patterns exist in office design's impact. The three included studies investigate office type's association with employees' welfare by measuring its influence on: a) perception of leadership, b) sick leave, and c) job satisfaction.The sample consists of office employees from a large, national representative work environment survey that work in one of the seven identified office types in contemporary office design: (1) cell-offices; (2) shared-room offices; (3) small, (4) medium-sized and (5) large open-plan offices; (6) flex-offices and (7) combi-offices. Statistical method used is multivariate logistic and linear regression analysis with adjustment for background factors. Overall results show that shared-room office, traditional open plan offices and flex-office stand out negatively, but to different degree(s) on the different outcomes measured. This explorative comparison of different studies finds a pattern of office types that repeatedly show indications of negative influence on employees' welfare, but further studies are needed to clarify this.

Measuring motivation in people with schizophrenia.

PubMed

Fervaha, Gagan; Foussias, George; Takeuchi, Hiroyoshi; Agid, Ofer; Remington, Gary

2015-12-01

Motivational deficits are a key determinant of poor functional outcomes in schizophrenia. These impairments are typically evaluated using various clinical rating scales; however, the degree of convergence between motivation scores derived from different instruments is not clear. In the present study, we measured motivational deficits in 62 patients with schizophrenia using 5 scores derived from 3 different instruments. We found that the scores from these different instruments were highly inter-correlated, and largely independent of severity of other symptom domains (e.g., depression). Our findings suggest that clinical ratings scales evaluating motivational deficits are tapping into a similar underlying construct. Copyright © 2015 Elsevier B.V. All rights reserved.

Bounds on Block Error Probability for Multilevel Concatenated Codes

NASA Technical Reports Server (NTRS)

Lin, Shu; Moorthy, Hari T.; Stojanovic, Diana

1996-01-01

Maximum likelihood decoding of long block codes is not feasable due to large complexity. Some classes of codes are shown to be decomposable into multilevel concatenated codes (MLCC). For these codes, multistage decoding provides good trade-off between performance and complexity. In this paper, we derive an upper bound on the probability of block error for MLCC. We use this bound to evaluate difference in performance for different decompositions of some codes. Examples given show that a significant reduction in complexity can be achieved when increasing number of stages of decoding. Resulting performance degradation varies for different decompositions. A guideline is given for finding good m-level decompositions.

Characteristics of Gamma-Ray Loud Blazars in the VLBA Imaging and Polarimetry Survey

NASA Technical Reports Server (NTRS)

Linford, J. D.; Taylor, G. B.; Romani, R. W.; Healey, S. E.; Helmboldt, J. F.; Readhead, A. C.; Reeves, R.; Richards, J. L.; Cotter, G.

2010-01-01

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey. This large, flux-limited sample of active galactic nuclei (AGNs) provides insights into the mechanism that produces strong gamma-ray emission. At lower flux levels, radio flux density does not directly correlate with gamma-ray flux. We find that the LAT-detected BL Lac objects tend to be similar to the non-LAT BL Lac objects, but that the LAT-detected FSRQs are often significantly different from the non-LAT FSRQs. The differences between the gamma-ray loud and quiet FSRQS can be explained by Doppler boosting; these objects appear to require larger Doppler factors than those of the BL Lac objects. It is possible that the gamma-ray loud FSRQs are fundamentally different from the gamma-ray quiet FSRQs. Strong polarization at the base of the jet appears to be a signature for gamma-ray loud AGNs.

Evaluation of Bias-Variance Trade-Off for Commonly Used Post-Summarizing Normalization Procedures in Large-Scale Gene Expression Studies

PubMed Central

Qiu, Xing; Hu, Rui; Wu, Zhixin

2014-01-01

Normalization procedures are widely used in high-throughput genomic data analyses to remove various technological noise and variations. They are known to have profound impact to the subsequent gene differential expression analysis. Although there has been some research in evaluating different normalization procedures, few attempts have been made to systematically evaluate the gene detection performances of normalization procedures from the bias-variance trade-off point of view, especially with strong gene differentiation effects and large sample size. In this paper, we conduct a thorough study to evaluate the effects of normalization procedures combined with several commonly used statistical tests and MTPs under different configurations of effect size and sample size. We conduct theoretical evaluation based on a random effect model, as well as simulation and biological data analyses to verify the results. Based on our findings, we provide some practical guidance for selecting a suitable normalization procedure under different scenarios. PMID:24941114

Walking in Two French Neighborhoods: A Study of How Park Numbers and Locations Relate to Everyday Walking

PubMed Central

Rioux, Liliane; Werner, Carol M.; Mokounkolo, Rene; Brown, Barbara B.

2017-01-01

Research indicates that people are drawn to green spaces with attractive amenities. This study extends that finding by comparing walking patterns in two neighborhoods with different numbers of parks; parks did not differ in rated attractiveness nor did neighborhoods differ substantially in rated walkability. Adults, aged 32–86 years (n = 90), drew their 3 most recent walking routes on maps of their neighborhood. Analyses showed that participants’ round trips were longer by 265.5 meters (.16 mile) in the neighborhood with a single, large, centrally located park (p < .02). However, participants in the neighborhood with multiple, small, more distributed parks, visited more streets, p < .001, more streets with green spaces, p < .038, and used more varied routes, p < .012. Results suggest there are potential benefits to both layouts. Large centralized parks may invite longer walks; smaller, well-distributed parks may invite more varied routes suggestive of appropriation and motivation processes. Both layouts might be combined in a single neighborhood to attract more walkers. PMID:28579664

Understanding life together: A brief history of collaboration in biology

PubMed Central

Vermeulen, Niki; Parker, John N.; Penders, Bart

2013-01-01

The history of science shows a shift from single-investigator ‘little science’ to increasingly large, expensive, multinational, interdisciplinary and interdependent ‘big science’. In physics and allied fields this shift has been well documented, but the rise of collaboration in the life sciences and its effect on scientific work and knowledge has received little attention. Research in biology exhibits different historical trajectories and organisation of collaboration in field and laboratory – differences still visible in contemporary collaborations such as the Census of Marine Life and the Human Genome Project. We employ these case studies as strategic exemplars, supplemented with existing research on collaboration in biology, to expose the different motives, organisational forms and social dynamics underpinning contemporary large-scale collaborations in biology and their relations to historical patterns of collaboration in the life sciences. We find the interaction between research subject, research approach as well as research organisation influencing collaboration patterns and the work of scientists. PMID:23578694

Adolescents and adults at the mall: dyadic interactions.

PubMed

Readdick, C A; Mullis, R L

1997-01-01

The purpose of this descriptive study is to examine differences in interpersonal engagements between teen-teen dyads and teen-adults dyads in a mall setting. It was expected that behavioral patterns between teen-teen and teen-adult dyads would differ as a function of age, gender, and racial composition. Participants included 865 teen-teen dyads and 190 teen-adult dyads. Observations were conducted in a large mall over four weeks. Observers recorded behavioral activity, physical proximity/position, emotional expression, conversation, and evidence of shopping. Teen-teen dyads differed from teen-adult dyads on two variables, conversation and shopping evidence. Within teen-teen dyad comparisons yielded several gender and racial differences, but only one age difference. Implications of these findings are discussed.

Adolescent Self-Esteem: Differences by Race/Ethnicity, Gender, and Age

PubMed Central

Bachman, Jerald G.; O’Malley, Patrick M.; Freedman-Doan, Peter; Trzesniewski, Kali H.; Donnellan, M. Brent

2012-01-01

Large-scale representative surveys of 8th-, 10th-, and 12th-grade students in the United States show high self-esteem scores for all groups. African-American students score highest, Whites score slightly higher than Hispanics, and Asian Americans score lowest. Males score slightly higher than females. Multivariate controls for grades and college plans actually heighten these race/ethnic/gender differences. A truncated scoring method, designed to counter race/ethnic differences in extreme response style, reduced but did not eliminate the subgroup differences. Age differences in self-esteem are modest, with 12th graders reporting the highest scores. The findings are highly consistent across 18 annual surveys from 1991 through 2008, and self-esteem scores show little overall change during that period. PMID:22279425

Stochastic win-stay-lose-shift strategy with dynamic aspirations in evolutionary social dilemmas

NASA Astrophysics Data System (ADS)

Amaral, Marco A.; Wardil, Lucas; Perc, Matjaž; da Silva, Jafferson K. L.

2016-09-01

In times of plenty expectations rise, just as in times of crisis they fall. This can be mathematically described as a win-stay-lose-shift strategy with dynamic aspiration levels, where individuals aspire to be as wealthy as their average neighbor. Here we investigate this model in the realm of evolutionary social dilemmas on the square lattice and scale-free networks. By using the master equation and Monte Carlo simulations, we find that cooperators coexist with defectors in the whole phase diagram, even at high temptations to defect. We study the microscopic mechanism that is responsible for the striking persistence of cooperative behavior and find that cooperation spreads through second-order neighbors, rather than by means of network reciprocity that dominates in imitation-based models. For the square lattice the master equation can be solved analytically in the large temperature limit of the Fermi function, while for other cases the resulting differential equations must be solved numerically. Either way, we find good qualitative agreement with the Monte Carlo simulation results. Our analysis also reveals that the evolutionary outcomes are to a large degree independent of the network topology, including the number of neighbors that are considered for payoff determination on lattices, which further corroborates the local character of the microscopic dynamics. Unlike large-scale spatial patterns that typically emerge due to network reciprocity, here local checkerboard-like patterns remain virtually unaffected by differences in the macroscopic properties of the interaction network.

Biclustering sparse binary genomic data.

PubMed

van Uitert, Miranda; Meuleman, Wouter; Wessels, Lodewyk

2008-12-01

Genomic datasets often consist of large, binary, sparse data matrices. In such a dataset, one is often interested in finding contiguous blocks that (mostly) contain ones. This is a biclustering problem, and while many algorithms have been proposed to deal with gene expression data, only two algorithms have been proposed that specifically deal with binary matrices. None of the gene expression biclustering algorithms can handle the large number of zeros in sparse binary matrices. The two proposed binary algorithms failed to produce meaningful results. In this article, we present a new algorithm that is able to extract biclusters from sparse, binary datasets. A powerful feature is that biclusters with different numbers of rows and columns can be detected, varying from many rows to few columns and few rows to many columns. It allows the user to guide the search towards biclusters of specific dimensions. When applying our algorithm to an input matrix derived from TRANSFAC, we find transcription factors with distinctly dissimilar binding motifs, but a clear set of common targets that are significantly enriched for GO categories.

Craniocervical junction in dogs revisited--new ligaments and confirmed presence of enthesis fibrocartilage.

PubMed

Kupczynska, M; Wieladek, A; Janczyk, P

2012-06-01

The study was performed to investigate and to describe features of gross and microscopic morphology of craniocervical junction (CCJ) in dogs. Seventy mature dogs (38 females, 32 males) of different body weight, representing small, medium and large breeds of dolicho-, mesati-, and brachycephalic morphotype were dissected. Morphological details were localised using an operating microscope with integrated video channel. Occurrence and distribution of fibrocartilage in the ligaments from 10 dogs was analysed histologically. Three new pairs of ligaments were described and named: dorsal ligaments of atlas, cranial internal collateral ligaments of atlas, and caudal internal collateral ligaments of atlas. Several new findings in the course of the known ligaments were found relating to breed and body weight. For the first time enthesis fibrocartilage was identified in ligaments of CCJ in dogs. Sesamoidal fibrocartilage was identified in the transversal ligament of atlas in large dogs. The findings are discussed for clinical importance. Copyright © 2011 Elsevier Ltd. All rights reserved.

Elucidating the genetic architecture of reproductive ageing in the Japanese population.

PubMed

Horikoshi, Momoko; Day, Felix R; Akiyama, Masato; Hirata, Makoto; Kamatani, Yoichiro; Matsuda, Koichi; Ishigaki, Kazuyoshi; Kanai, Masahiro; Wright, Hollis; Toro, Carlos A; Ojeda, Sergio R; Lomniczi, Alejandro; Kubo, Michiaki; Ong, Ken K; Perry, John R B

2018-05-17

Population studies elucidating the genetic architecture of reproductive ageing have been largely limited to European ancestries, restricting the generalizability of the findings and overlooking possible key genes poorly captured by common European genetic variation. Here, we report 26 loci (all P < 5 × 10 -8 ) for reproductive ageing, i.e. puberty timing or age at menopause, in a non-European population (up to 67,029 women of Japanese ancestry). Highlighted genes for menopause include GNRH1, which supports a primary, rather than passive, role for hypothalamic-pituitary GnRH signalling in the timing of menopause. For puberty timing, we demonstrate an aetiological role for receptor-like protein tyrosine phosphatases by combining evidence across population genetics and pre- and peri-pubertal changes in hypothalamic gene expression in rodent and primate models. Furthermore, our findings demonstrate widespread differences in allele frequencies and effect estimates between Japanese and European associated variants, highlighting the benefits and challenges of large-scale trans-ethnic approaches.

Statistical mechanics of complex economies

NASA Astrophysics Data System (ADS)

Bardoscia, Marco; Livan, Giacomo; Marsili, Matteo

2017-04-01

In the pursuit of ever increasing efficiency and growth, our economies have evolved to remarkable degrees of complexity, with nested production processes feeding each other in order to create products of greater sophistication from less sophisticated ones, down to raw materials. The engine of such an expansion have been competitive markets that, according to general equilibrium theory (GET), achieve efficient allocations under specific conditions. We study large random economies within the GET framework, as templates of complex economies, and we find that a non-trivial phase transition occurs: the economy freezes in a state where all production processes collapse when either the number of primary goods or the number of available technologies fall below a critical threshold. As in other examples of phase transitions in large random systems, this is an unintended consequence of the growth in complexity. Our findings suggest that the Industrial Revolution can be regarded as a sharp transition between different phases, but also imply that well developed economies can collapse if too many intermediate goods are introduced.

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

Ben-Naim, Eli; Krapivsky, Paul

Here we generalize the ordinary aggregation process to allow for choice. In ordinary aggregation, two random clusters merge and form a larger aggregate. In our implementation of choice, a target cluster and two candidate clusters are randomly selected and the target cluster merges with the larger of the two candidate clusters.We study the long-time asymptotic behavior and find that as in ordinary aggregation, the size density adheres to the standard scaling form. However, aggregation with choice exhibits a number of different features. First, the density of the smallest clusters exhibits anomalous scaling. Second, both the small-size and the large-size tailsmore » of the density are overpopulated, at the expense of the density of moderate-size clusters. Finally, we also study the complementary case where the smaller candidate cluster participates in the aggregation process and find an abundance of moderate clusters at the expense of small and large clusters. Additionally, we investigate aggregation processes with choice among multiple candidate clusters and a symmetric implementation where the choice is between two pairs of clusters.« less

Band Gap Engineering with Ultralarge Biaxial Strains in Suspended Monolayer MoS2.

PubMed

Lloyd, David; Liu, Xinghui; Christopher, Jason W; Cantley, Lauren; Wadehra, Anubhav; Kim, Brian L; Goldberg, Bennett B; Swan, Anna K; Bunch, J Scott

2016-09-14

We demonstrate the continuous and reversible tuning of the optical band gap of suspended monolayer MoS2 membranes by as much as 500 meV by applying very large biaxial strains. By using chemical vapor deposition (CVD) to grow crystals that are highly impermeable to gas, we are able to apply a pressure difference across suspended membranes to induce biaxial strains. We observe the effect of strain on the energy and intensity of the peaks in the photoluminescence (PL) spectrum and find a linear tuning rate of the optical band gap of 99 meV/%. This method is then used to study the PL spectra of bilayer and trilayer devices under strain and to find the shift rates and Grüneisen parameters of two Raman modes in monolayer MoS2. Finally, we use this result to show that we can apply biaxial strains as large as 5.6% across micron-sized areas and report evidence for the strain tuning of higher level optical transitions.

Child mental health differences amongst ethnic groups in Britain: a systematic review

PubMed Central

Goodman, Anna; Patel, Vikram; Leon, David A

2008-01-01

Background Inter-ethnic differences have been reported for many mental health outcomes in the UK, but no systematic review on child mental health has been published. The aim of this review is to compare the population-based prevalence of child mental disorders between ethnic groups in Britain, and relate these findings to ethnic differences in mental health service use. Methods A systematic search of bibliographic databases for population-based and clinic-based studies of children aged 0–19, including all ethnic groups and the main child mental disorders. We synthesised findings by comparing each minority group to the White British study sample. Results 31 population-based and 18 clinic-based studies met the inclusion criteria. Children in the main minority groups have similar or better mental health than White British children for common disorders, but may have higher rates for some less common conditions. The causes of these differences are unclear. There may be unmet need for services among Pakistani and Bangladeshi children. Conclusion Inter-ethnic differences exist but are largely unexplained. Future studies should address the challenges of cross-cultural psychiatry and investigate reasons for inter-ethnic differences. PMID:18655701

The maximum rate of mammal evolution

NASA Astrophysics Data System (ADS)

Evans, Alistair R.; Jones, David; Boyer, Alison G.; Brown, James H.; Costa, Daniel P.; Ernest, S. K. Morgan; Fitzgerald, Erich M. G.; Fortelius, Mikael; Gittleman, John L.; Hamilton, Marcus J.; Harding, Larisa E.; Lintulaakso, Kari; Lyons, S. Kathleen; Okie, Jordan G.; Saarinen, Juha J.; Sibly, Richard M.; Smith, Felisa A.; Stephens, Patrick R.; Theodor, Jessica M.; Uhen, Mark D.

2012-03-01

How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous-Paleogene (K-Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes.

In Forests Globally, Large Trees Suffer Most during Drought

NASA Astrophysics Data System (ADS)

Bennett, A. C.; McDowell, N. G.; Allen, C. D.; Anderson-Teixeira, K. J.

2014-12-01

Globally, drought events are increasing in both frequency and intensity. Spatial and temporal variation in water availability is expected to alter the ecophysiology and structure of forests, with consequent feedbacks to climate change. Extensive tree mortality induced by heat and aridity has been documented across a range of latitudes, and several global vegetation models have simulated widespread forest die-off in the future. The impact of drought on forest structure and function will depend on the differential responses of trees of different sizes. Understanding the size-dependence of drought-induced mortality is necessary to predict local and global impacts. Here we show that in forests worldwide, drought has a greater impact on the growth and mortality of large trees compared to smaller trees. This trend holds true for forests ranging from semiarid woodlands to tropical rainforests. This finding contrasts with what would be expected if deep root access to water were the primary determinant of tree drought response. Rather, the greater drought response of larger trees could be driven by greater inherent vulnerability of large trees to hydraulic stress or by canopy position becoming more of a liability under drought, as exposed crowns face higher evaporative demand. These findings imply that future droughts will have a disproportionate effect on large trees, resulting in a larger feedback to climate change than would occur if all tree size classes were equally affected by drought.

Wire Marking Results in a Small but Significant Reduction in Avian Mortality at Power Lines: A BACI Designed Study

PubMed Central

Barrientos, Rafael; Ponce, Carlos; Palacín, Carlos; Martín, Carlos A.; Martín, Beatriz; Alonso, Juan Carlos

2012-01-01

Background Collision with electric power lines is a conservation problem for many bird species. Although the implementation of flight diverters is rapidly increasing, few well-designed studies supporting the effectiveness of this costly conservation measure have been published. Methodology/Principal Findings We provide information on the largest worldwide marking experiment to date, including carcass searches at 35 (15 experimental, 20 control) power lines totalling 72.5 km, at both transmission (220 kV) and distribution (15 kV–45 kV) lines. We found carcasses of 45 species, 19 of conservation concern. Numbers of carcasses found were corrected to account for carcass losses due to removal by scavengers or being overlooked by researchers, resulting in an estimated collision rate of 8.2 collisions per km per month. We observed a small (9.6%) but significant decrease in the number of casualties after line marking compared to before line marking in experimental lines. This was not observed in control lines. We found no influence of either marker size (large vs. small spirals, sample of distribution lines only) or power line type (transmission vs. distribution, sample of large spirals only) on the collision rate when we analyzed all species together. However, great bustard mortality was slightly lower when lines were marked with large spirals and in transmission lines after marking. Conclusions Our results confirm the overall effectiveness of wire marking as a way to reduce, but not eliminate, bird collisions with power lines. If raw field data are not corrected by carcass losses due to scavengers and missed observations, findings may be biased. The high cost of this conservation measure suggests a need for more studies to improve its application, including wire marking with non-visual devices. Our findings suggest that different species may respond differently to marking, implying that species-specific patterns should be explored, at least for species of conservation concern. PMID:22396776

PROPER: global protein interaction network alignment through percolation matching.

PubMed

Kazemi, Ehsan; Hassani, Hamed; Grossglauser, Matthias; Pezeshgi Modarres, Hassan

2016-12-12

The alignment of protein-protein interaction (PPI) networks enables us to uncover the relationships between different species, which leads to a deeper understanding of biological systems. Network alignment can be used to transfer biological knowledge between species. Although different PPI-network alignment algorithms were introduced during the last decade, developing an accurate and scalable algorithm that can find alignments with high biological and structural similarities among PPI networks is still challenging. In this paper, we introduce a new global network alignment algorithm for PPI networks called PROPER. Compared to other global network alignment methods, our algorithm shows higher accuracy and speed over real PPI datasets and synthetic networks. We show that the PROPER algorithm can detect large portions of conserved biological pathways between species. Also, using a simple parsimonious evolutionary model, we explain why PROPER performs well based on several different comparison criteria. We highlight that PROPER has high potential in further applications such as detecting biological pathways, finding protein complexes and PPI prediction. The PROPER algorithm is available at http://proper.epfl.ch .

Ratio index variables or ANCOVA? Fisher's cats revisited.

PubMed

Tu, Yu-Kang; Law, Graham R; Ellison, George T H; Gilthorpe, Mark S

2010-01-01

Over 60 years ago Ronald Fisher demonstrated a number of potential pitfalls with statistical analyses using ratio variables. Nonetheless, these pitfalls are largely overlooked in contemporary clinical and epidemiological research, which routinely uses ratio variables in statistical analyses. This article aims to demonstrate how very different findings can be generated as a result of less than perfect correlations among the data used to generate ratio variables. These imperfect correlations result from measurement error and random biological variation. While the former can often be reduced by improvements in measurement, random biological variation is difficult to estimate and eliminate in observational studies. Moreover, wherever the underlying biological relationships among epidemiological variables are unclear, and hence the choice of statistical model is also unclear, the different findings generated by different analytical strategies can lead to contradictory conclusions. Caution is therefore required when interpreting analyses of ratio variables whenever the underlying biological relationships among the variables involved are unspecified or unclear. (c) 2009 John Wiley & Sons, Ltd.

For blacks in America, the gap in neighborhood poverty has declined faster than segregation

PubMed Central

Acciai, Francesco

2016-01-01

Black residential segregation has been declining in the United States. That accomplishment rings hollow, however, if blacks continue to live in much poorer neighborhoods than other Americans. This study uses census data for all US metropolitan areas in 1980 and 2010 to compare decline in the neighborhood poverty gap between blacks and other Americans with decline in the residential segregation of blacks. We find that both declines resulted primarily from narrowing differences between blacks and whites as opposed to narrowing differences between blacks and Hispanics or blacks and Asians. Because black–white differences in neighborhood poverty declined much faster than black–white segregation, the neighborhood poverty disadvantage of blacks declined faster than black segregation—a noteworthy finding because the narrowing of the racial gap in neighborhood poverty for blacks has gone largely unnoticed. Further analysis reveals that the narrowing of the gap was produced by change in both the medians and shapes of the distribution of poverty across the neighborhoods where blacks, whites, Hispanics, and Asians reside. PMID:27821759

Mental Imagery, Impact, and Affect: A Mediation Model for Charitable Giving

PubMed Central

Dickert, Stephan; Kleber, Janet; Västfjäll, Daniel; Slovic, Paul

2016-01-01

One of the puzzling phenomena in philanthropy is that people can show strong compassion for identified individual victims but remain unmoved by catastrophes that affect large numbers of victims. Two prominent findings in research on charitable giving reflect this idiosyncrasy: The (1) identified victim and (2) victim number effects. The first of these suggests that identifying victims increases donations and the second refers to the finding that people’s willingness to donate often decreases as the number of victims increases. While these effects have been documented in the literature, their underlying psychological processes need further study. We propose a model in which identified victim and victim number effects operate through different cognitive and affective mechanisms. In two experiments we present empirical evidence for such a model and show that different affective motivations (donor-focused vs. victim-focused feelings) are related to the cognitive processes of impact judgments and mental imagery. Moreover, we argue that different mediation pathways exist for identifiability and victim number effects. PMID:26859848

Mental Imagery, Impact, and Affect: A Mediation Model for Charitable Giving.

PubMed

Dickert, Stephan; Kleber, Janet; Västfjäll, Daniel; Slovic, Paul

2016-01-01

One of the puzzling phenomena in philanthropy is that people can show strong compassion for identified individual victims but remain unmoved by catastrophes that affect large numbers of victims. Two prominent findings in research on charitable giving reflect this idiosyncrasy: The (1) identified victim and (2) victim number effects. The first of these suggests that identifying victims increases donations and the second refers to the finding that people's willingness to donate often decreases as the number of victims increases. While these effects have been documented in the literature, their underlying psychological processes need further study. We propose a model in which identified victim and victim number effects operate through different cognitive and affective mechanisms. In two experiments we present empirical evidence for such a model and show that different affective motivations (donor-focused vs. victim-focused feelings) are related to the cognitive processes of impact judgments and mental imagery. Moreover, we argue that different mediation pathways exist for identifiability and victim number effects.

Market structure and competition in the healthcare industry : Results from a transition economy.

PubMed

Lábaj, Martin; Silanič, Peter; Weiss, Christoph; Yontcheva, Biliana

2018-02-14

The present paper provides first empirical evidence on the relationship between market size and the number of firms in the healthcare industry for a transition economy. We estimate market-size thresholds required to support different numbers of suppliers (firms) for three occupations in the healthcare industry in a large number of distinct geographic markets in Slovakia, taking into account the spatial interaction between local markets. The empirical analysis is carried out for three time periods (1995, 2001 and 2010) which characterise different stages of the transition process. Our results suggest that the relationship between market size and the number of firms differs both across industries and across periods. In particular, we find that pharmacies, as the only completely liberalised market in our dataset, experience the largest change in competitive behaviour during the transition process. Furthermore, we find evidence for correlation in entry decisions across administrative borders, suggesting that future market analysis should aim to capture these regional effects.

For blacks in America, the gap in neighborhood poverty has declined faster than segregation.

PubMed

Firebaugh, Glenn; Acciai, Francesco

2016-11-22

Black residential segregation has been declining in the United States. That accomplishment rings hollow, however, if blacks continue to live in much poorer neighborhoods than other Americans. This study uses census data for all US metropolitan areas in 1980 and 2010 to compare decline in the neighborhood poverty gap between blacks and other Americans with decline in the residential segregation of blacks. We find that both declines resulted primarily from narrowing differences between blacks and whites as opposed to narrowing differences between blacks and Hispanics or blacks and Asians. Because black-white differences in neighborhood poverty declined much faster than black-white segregation, the neighborhood poverty disadvantage of blacks declined faster than black segregation-a noteworthy finding because the narrowing of the racial gap in neighborhood poverty for blacks has gone largely unnoticed. Further analysis reveals that the narrowing of the gap was produced by change in both the medians and shapes of the distribution of poverty across the neighborhoods where blacks, whites, Hispanics, and Asians reside.

Network overload due to massive attacks

NASA Astrophysics Data System (ADS)

Kornbluth, Yosef; Barach, Gilad; Tuchman, Yaakov; Kadish, Benjamin; Cwilich, Gabriel; Buldyrev, Sergey V.

2018-05-01

We study the cascading failure of networks due to overload, using the betweenness centrality of a node as the measure of its load following the Motter and Lai model. We study the fraction of survived nodes at the end of the cascade pf as a function of the strength of the initial attack, measured by the fraction of nodes p that survive the initial attack for different values of tolerance α in random regular and Erdös-Renyi graphs. We find the existence of a first-order phase-transition line pt(α ) on a p -α plane, such that if p pt , pf is large and the giant component of the network is still present. Exactly at pt, the function pf(p ) undergoes a first-order discontinuity. We find that the line pt(α ) ends at a critical point (pc,αc) , in which the cascading failures are replaced by a second-order percolation transition. We find analytically the average betweenness of nodes with different degrees before and after the initial attack, we investigate their roles in the cascading failures, and we find a lower bound for pt(α ) . We also study the difference between localized and random attacks.

Improving GRADE evidence tables part 1: a randomized trial shows improved understanding of content in summary of findings tables with a new format.

PubMed

Carrasco-Labra, Alonso; Brignardello-Petersen, Romina; Santesso, Nancy; Neumann, Ignacio; Mustafa, Reem A; Mbuagbaw, Lawrence; Etxeandia Ikobaltzeta, Itziar; De Stio, Catherine; McCullagh, Lauren J; Alonso-Coello, Pablo; Meerpohl, Joerg J; Vandvik, Per Olav; Brozek, Jan L; Akl, Elie A; Bossuyt, Patrick; Churchill, Rachel; Glenton, Claire; Rosenbaum, Sarah; Tugwell, Peter; Welch, Vivian; Garner, Paul; Guyatt, Gordon; Schünemann, Holger J

2016-06-01

The current format of summary of findings (SoFs) tables for presenting effect estimates and associated quality of evidence improve understanding and assist users finding key information in systematic reviews. Users of SoF tables have demanded alternative formats to express findings from systematic reviews. We conducted a randomized controlled trial among systematic review users to compare the relative merits of a new format with the current formats of SoF tables regarding understanding, accessibility of information, satisfaction, and preference. Our primary goal was to show that the new format is not inferior to the current format. Of 390 potentially eligible subjects, 290 were randomized. Of seven items testing understanding, three showed similar results, two showed small differences favoring the new format, and two (understanding risk difference and quality of the evidence associated with a treatment effect) showed large differences favoring the new format [63% (95% confidence interval {CI}: 55, 71) and 62% (95% CI: 52, 71) more correct answers, respectively]. Respondents rated information in the alternative format as more accessible overall and preferred the new format over the current format. While providing at least similar levels of understanding for some items and increased understanding for others, users prefer the new format of SoF tables. Copyright © 2016 Elsevier Inc. All rights reserved.

Unreported workers' compensation claims to the BLS Survey of Occupational Injuries and Illnesses: Establishment factors.

PubMed

Wuellner, Sara E; Adams, Darrin A; Bonauto, David K

2016-04-01

Studies suggest employers underreport injuries to the Bureau of Labor Statistics Survey of Occupational Injuries and Illnesses (SOII); less is known about reporting differences by establishment characteristics. We linked SOII data to Washington State workers' compensation claims data, using unemployment insurance data to improve linking accuracy. We used multivariable regression models to estimate incidence ratios (IR) of unreported workers' compensation claims for establishment characteristics. An estimated 70% of workers' compensation claims were reported in SOII. Claims among state and local government establishments were most likely to be reported. Compared to large manufacturing establishments, unreported claims were most common among small educational services establishments (IR = 2.47, 95%CI: 1.52-4.01) and large construction establishments (IR = 2.05, 95%CI: 1.77-2.37). Underreporting of workers' compensation claims to SOII varies by establishment characteristics, obscuring true differences in work injury incidence. Findings may differ from previous research due to differences in study methods. © 2016 The Authors. American Journal of Industrial Medicine Published by Wiley Periodicals, Inc.

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

Hu, Dehua; Liu, Qing; Tisdale, Jeremy

This paper reports Seebeck effects driven by both surface polarization difference and entropy difference by using intramolecular charge-transfer states in n-type and p-type conjugated polymers, namely IIDT and IIDDT, based on vertical conductor/polymer/conductor thin-film devices. Large Seebeck coefficients of -898 V/K and 1300 V/K from are observed from n-type IIDT p-type IIDDT, respectively, when the charge-transfer states are generated by a white light illumination of 100 mW/cm2. Simultaneously, electrical conductivities are increased from almost insulating states in dark condition to conducting states under photoexcitation in both n-type IIDT and p-type IIDDT devices. We find that the intramolecular charge-transfer states canmore » largely enhance Seebeck effects in the n-type IIDT and p-type IIDDT devices driven by both surface polarization difference and entropy difference. Furthermore, the Seebeck effects can be shifted between polarization and entropy regimes when electrical conductivities are changed. This reveals a new concept to develop Seebeck effects by controlling polarization and entropy regimes based on charge-transfer states in vertical conductor/polymer/conductor thin-film devices.« less

Sensitivity of CO2 Simulation in a GCM to the Convective Transport Algorithms

NASA Technical Reports Server (NTRS)

Zhu, Z.; Pawson, S.; Collatz, G. J.; Gregg, W. W.; Kawa, S. R.; Baker, D.; Ott, L.

2014-01-01

Convection plays an important role in the transport of heat, moisture and trace gases. In this study, we simulated CO2 concentrations with an atmospheric general circulation model (GCM). Three different convective transport algorithms were used. One is a modified Arakawa-Shubert scheme that was native to the GCM; two others used in two off-line chemical transport models (CTMs) were added to the GCM here for comparison purposes. Advanced CO2 surfaced fluxes were used for the simulations. The results were compared to a large quantity of CO2 observation data. We find that the simulation results are sensitive to the convective transport algorithms. Overall, the three simulations are quite realistic and similar to each other in the remote marine regions, but are significantly different in some land regions with strong fluxes such as Amazon and Siberia during the convection seasons. Large biases against CO2 measurements are found in these regions in the control run, which uses the original GCM. The simulation with the simple diffusive algorithm is better. The difference of the two simulations is related to the very different convective transport speed.

Classification of epilepsy types through global network analysis of scalp electroencephalograms

NASA Astrophysics Data System (ADS)

Lee, Uncheol; Kim, Seunghwan; Jung, Ki-Young

2006-04-01

Epilepsy is a dynamic disease in which self-organization and emergent structures occur dynamically at multiple levels of neuronal integration. Therefore, the transient relationship within multichannel electroencephalograms (EEGs) is crucial for understanding epileptic processes. In this paper, we show that the global relationship within multichannel EEGs provides us with more useful information in classifying two different epilepsy types than pairwise relationships such as cross correlation. To demonstrate this, we determine the global network structure within channels of the scalp EEG based on the minimum spanning tree method. The topological dissimilarity of the network structures from different types of temporal lobe epilepsy is described in the form of the divergence rate and is computed for 11 patients with left (LTLE) and right temporal lobe epilepsy (RTLE). We find that patients with LTLE and RTLE exhibit different large scale network structures, which emerge at the epoch immediately before the seizure onset, not in the preceding epochs. Our results suggest that patients with the two different epilepsy types display distinct large scale dynamical networks with characteristic epileptic network structures.

Gender Differences in Academic Achievement: Is Writing an Exception to the Gender Similarities Hypothesis?

PubMed

Reynolds, Matthew R; Scheiber, Caroline; Hajovsky, Daniel B; Schwartz, Bryanna; Kaufman, Alan S

2015-01-01

The gender similarities hypothesis by J. S. Hyde ( 2005 ), based on large-scale reviews of studies, concludes that boys and girls are more alike than different on most psychological variables, including academic skills such as reading and math (J. S. Hyde, 2005 ). Writing is an academic skill that may be an exception. The authors investigated gender differences in academic achievement using a large, nationally stratified sample of children and adolescents ranging from ages 7-19 years (N = 2,027). Achievement data were from the conormed sample for the Kaufman intelligence and achievement tests. Multiple-indicator, multiple-cause, and multigroup mean and covariance structure models were used to test for mean differences. Girls had higher latent reading ability and higher scores on a test of math computation, but the effect sizes were consistent with the gender similarities hypothesis. Conversely, girls scored higher on spelling and written expression, with effect sizes inconsistent with the gender similarities hypothesis. The findings remained the same after controlling for cognitive ability. Girls outperform boys on tasks of writing.

Differences in the Reporting of Racial and Socioeconomic Disparities among Three Large National Databases for Breast Reconstruction.

PubMed

Kamali, Parisa; Zettervall, Sara L; Wu, Winona; Ibrahim, Ahmed M S; Medin, Caroline; Rakhorst, Hinne A; Schermerhorn, Marc L; Lee, Bernard T; Lin, Samuel J

2017-04-01

Research derived from large-volume databases plays an increasing role in the development of clinical guidelines and health policy. In breast cancer research, the Surveillance, Epidemiology and End Results, National Surgical Quality Improvement Program, and Nationwide Inpatient Sample databases are widely used. This study aims to compare the trends in immediate breast reconstruction and identify the drawbacks and benefits of each database. Patients with invasive breast cancer and ductal carcinoma in situ were identified from each database (2005-2012). Trends of immediate breast reconstruction over time were evaluated. Patient demographics and comorbidities were compared. Subgroup analysis of immediate breast reconstruction use per race was conducted. Within the three databases, 1.2 million patients were studied. Immediate breast reconstruction in invasive breast cancer patients increased significantly over time in all databases. A similar significant upward trend was seen in ductal carcinoma in situ patients. Significant differences in immediate breast reconstruction rates were seen among races; and the disparity differed among the three databases. Rates of comorbidities were similar among the three databases. There has been a significant increase in immediate breast reconstruction; however, the extent of the reporting of overall immediate breast reconstruction rates and of racial disparities differs significantly among databases. The Nationwide Inpatient Sample and the National Surgical Quality Improvement Program report similar findings, with the Surveillance, Epidemiology and End Results database reporting results significantly lower in several categories. These findings suggest that use of the Surveillance, Epidemiology and End Results database may not be universally generalizable to the entire U.S.

Sensing emotion in voices: Negativity bias and gender differences in a validation study of the Oxford Vocal ('OxVoc') sounds database.

PubMed

Young, Katherine S; Parsons, Christine E; LeBeau, Richard T; Tabak, Benjamin A; Sewart, Amy R; Stein, Alan; Kringelbach, Morten L; Craske, Michelle G

2017-08-01

Emotional expressions are an essential element of human interactions. Recent work has increasingly recognized that emotional vocalizations can color and shape interactions between individuals. Here we present data on the psychometric properties of a recently developed database of authentic nonlinguistic emotional vocalizations from human adults and infants (the Oxford Vocal 'OxVoc' Sounds Database; Parsons, Young, Craske, Stein, & Kringelbach, 2014). In a large sample (n = 562), we demonstrate that adults can reliably categorize these sounds (as 'positive,' 'negative,' or 'sounds with no emotion'), and rate valence in these sounds consistently over time. In an extended sample (n = 945, including the initial n = 562), we also investigated a number of individual difference factors in relation to valence ratings of these vocalizations. Results demonstrated small but significant effects of (a) symptoms of depression and anxiety with more negative ratings of adult neutral vocalizations (R2 = .011 and R2 = .008, respectively) and (b) gender differences in perceived valence such that female listeners rated adult neutral vocalizations more positively and infant cry vocalizations more negatively than male listeners (R2 = .021, R2 = .010, respectively). Of note, we did not find evidence of negativity bias among other affective vocalizations or gender differences in perceived valence of adult laughter, adult cries, infant laughter, or infant neutral vocalizations. Together, these findings largely converge with factors previously shown to impact processing of emotional facial expressions, suggesting a modality-independent impact of depression, anxiety, and listener gender, particularly among vocalizations with more ambiguous valence. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Individual differences in face-looking behavior generalize from the lab to the world.

PubMed

Peterson, Matthew F; Lin, Jing; Zaun, Ian; Kanwisher, Nancy

2016-05-01

Recent laboratory studies have found large, stable individual differences in the location people first fixate when identifying faces, ranging from the brows to the mouth. Importantly, this variation is strongly associated with differences in fixation-specific identification performance such that individuals' recognition ability is maximized when looking at their preferred location (Mehoudar, Arizpe, Baker, & Yovel, 2014; Peterson & Eckstein, 2013). This finding suggests that face representations are retinotopic and individuals enact gaze strategies that optimize identification, yet the extent to which this behavior reflects real-world gaze behavior is unknown. Here, we used mobile eye trackers to test whether individual differences in face gaze generalize from lab to real-world vision. In-lab fixations were measured with a speeded face identification task, while real-world behavior was measured as subjects freely walked around the Massachusetts Institute of Technology campus. We found a strong correlation between the patterns of individual differences in face gaze in the lab and real-world settings. Our findings support the hypothesis that individuals optimize real-world face identification by consistently fixating the same location and thus strongly constraining the space of retinotopic input. The methods developed for this study entailed collecting a large set of high-definition, wide field-of-view natural videos from head-mounted cameras and the viewer's fixation position, allowing us to characterize subjects' actually experienced real-world retinotopic images. These images enable us to ask how vision is optimized not just for the statistics of the "natural images" found in web databases, but of the truly natural, retinotopic images that have landed on actual human retinae during real-world experience.

Kalman Filter Tracking on Parallel Architectures

NASA Astrophysics Data System (ADS)

Cerati, Giuseppe; Elmer, Peter; Krutelyov, Slava; Lantz, Steven; Lefebvre, Matthieu; McDermott, Kevin; Riley, Daniel; Tadel, Matevž; Wittich, Peter; Würthwein, Frank; Yagil, Avi

2016-11-01

Power density constraints are limiting the performance improvements of modern CPUs. To address this we have seen the introduction of lower-power, multi-core processors such as GPGPU, ARM and Intel MIC. In order to achieve the theoretical performance gains of these processors, it will be necessary to parallelize algorithms to exploit larger numbers of lightweight cores and specialized functions like large vector units. Track finding and fitting is one of the most computationally challenging problems for event reconstruction in particle physics. At the High-Luminosity Large Hadron Collider (HL-LHC), for example, this will be by far the dominant problem. The need for greater parallelism has driven investigations of very different track finding techniques such as Cellular Automata or Hough Transforms. The most common track finding techniques in use today, however, are those based on a Kalman filter approach. Significant experience has been accumulated with these techniques on real tracking detector systems, both in the trigger and offline. They are known to provide high physics performance, are robust, and are in use today at the LHC. Given the utility of the Kalman filter in track finding, we have begun to port these algorithms to parallel architectures, namely Intel Xeon and Xeon Phi. We report here on our progress towards an end-to-end track reconstruction algorithm fully exploiting vectorization and parallelization techniques in a simplified experimental environment.

Type of Violence, Age, and Gender Differences in the Effects of Family Violence on Children's Behavior Problems: A Mega-Analysis

ERIC Educational Resources Information Center

Sternberg, Kathleen J.; Baradaran, Laila P.; Abbott, Craig B.; Lamb, Michael E.; Guterman, Eva

2006-01-01

A mega-analytic study was designed to exploit the power of a large data set combining raw data from multiple studies (n=1870) to examine the effects of type of family violence, age, and gender on children's behavior problems assessed using the Child Behavior Checklist (CBCL). Our findings confirmed that children who experienced multiple forms of…

Similar Students, Different Results: Why Do Some Schools Do Better? Additional Findings: Elementary School Curriculum Program and API: A More Detailed Examination

ERIC Educational Resources Information Center

Levin, Jesse; Haertel, Edward; Kirst, Michael; Williams, Trish

2006-01-01

This research project surveyed 80% of the K-5 classroom teachers (over 5,500) and every principal at 257 elementary schools in California serving large percentages of low-income, minority, and English Learner students. Specifically, 98% percent of the schools in the sample qualified for Title I funding. The goal was to identify which specific…

What Sort of Girl Wants to Study Physics after the Age of 16? Findings from a Large-Scale UK Survey

ERIC Educational Resources Information Center

Mujtaba, Tamjid; Reiss, Michael J.

2013-01-01

This paper investigates the characteristics of 15-year-old girls who express an intention to study physics post-16. This paper unpacks issues around within-girl group differences and similarities between boys and girls in survey responses about physics. The analysis is based on the year 10 (age 15 years) responses of 5,034 students from 137 UK…

Propagation Environment Assessment Using UAV Electromagnetic Sensors

DTIC Science & Technology

2018-03-01

could be added, we limit this study to two dimensions.) The computer program then processes the data and determines the existence of any atmospheric... computer to have large processing capacity, and a typical workstation desktop or laptop can perform the function. E. FLIGHT PATTERNS AND DATA...different types of flight patterns were studied , and our findings show that the vertical flight pattern using a rotary platform is more efficient

1986 Petroleum Software Directory. [800 mini, micro and mainframe computer software packages

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

Not Available

1985-01-01

Pennwell's 1986 Petroleum Software Directory is a complete listing of software created specifically for the petroleum industry. Details are provided on over 800 mini, micro and mainframe computer software packages from more than 250 different companies. An accountant can locate programs to automate bookkeeping functions in large oil and gas production firms. A pipeline engineer will find programs designed to calculate line flow and wellbore pressure drop.

Performance analysis of parallel gravitational N-body codes on large GPU clusters

NASA Astrophysics Data System (ADS)

Huang, Si-Yi; Spurzem, Rainer; Berczik, Peter

2016-01-01

We compare the performance of two very different parallel gravitational N-body codes for astrophysical simulations on large Graphics Processing Unit (GPU) clusters, both of which are pioneers in their own fields as well as on certain mutual scales - NBODY6++ and Bonsai. We carry out benchmarks of the two codes by analyzing their performance, accuracy and efficiency through the modeling of structure decomposition and timing measurements. We find that both codes are heavily optimized to leverage the computational potential of GPUs as their performance has approached half of the maximum single precision performance of the underlying GPU cards. With such performance we predict that a speed-up of 200 - 300 can be achieved when up to 1k processors and GPUs are employed simultaneously. We discuss the quantitative information about comparisons of the two codes, finding that in the same cases Bonsai adopts larger time steps as well as larger relative energy errors than NBODY6++, typically ranging from 10 - 50 times larger, depending on the chosen parameters of the codes. Although the two codes are built for different astrophysical applications, in specified conditions they may overlap in performance at certain physical scales, thus allowing the user to choose either one by fine-tuning parameters accordingly.

Gravitational waves with dark matter minispikes: The combined effect

NASA Astrophysics Data System (ADS)

Yue, Xiao-Jun; Han, Wen-Biao

2018-03-01

It was shown that the dark matter (DM) minihalo around an intermediate mass black hole (IMBH) can be redistributed into a cusp, called the DM minispike. We consider an intermediate-mass-ratio inspiral consisting of an IMBH harbored in a DM minispike with nonannihilating DM particles and a small black hole (BH) orbiting around it. We investigate gravitational waves (GWs) produced by this system and analyze the waveforms with the comprehensive consideration of gravitational pull, dynamical friction and accretion of the minispike and calculate the time difference and phase difference caused by it. We find that for a certain range of frequency, the inspiralling time of the system is dramatically reduced for smaller central IMBH and large density of DM. For the central IMBH with 105 M⊙ , the time of merger is ahead, which can be distinguished by LISA, Taiji and Tianqin. We focus on the effect of accretion and compare it with that of gravitational pull and friction. We find that the accretion mass is a small quantity compared to the initial mass of the small BH and the accretion effect is inconspicuous compared with friction. However, the accumulated phase shift caused by accretion is large enough to be detected by LISA, Taiji, and Tianqin, which indicate that the accretion effect can not be ignored in the detection of GWs.

Temporal dynamics of online petitions

PubMed Central

Woolley-Meza, Olivia; Brockmann, Dirk

2017-01-01

Online petitions are an important avenue for direct political action, yet the dynamics that determine when a petition will be successful are not well understood. Here we analyze the temporal characteristics of online-petition signing behavior in order to identify systematic differences between popular petitions, which receive a high volume of signatures, and unpopular ones. We find that, in line with other temporal characterizations of human activity, the signing process is typically non-Poissonian and non-homogeneous in time. However, this process exhibits anomalously high memory for human activity, possibly indicating that synchronized external influence or contagion play and important role. More interestingly, we find clear differences in the characteristics of the inter-event time distributions depending on the total number of signatures that petitions receive, independently of the total duration of the petitions. Specifically, popular petitions that attract a large volume of signatures exhibit more variance in the distribution of inter-event times than unpopular petitions with only a few signatures, which could be considered an indication that the former are more bursty. However, petitions with large signature volume are less bursty according to measures that consider the time ordering of inter-event times. Our results, therefore, emphasize the importance of accounting for time ordering to characterize human activity. PMID:28542492

Comparisons of fish species traits from small streams to large rivers

USGS Publications Warehouse

Goldstein, R.M.; Meador, M.R.

2004-01-01

To examine the relations between fish community function and stream size, we classified 429 lotic freshwater fish species based on multiple categories within six species traits: (1) substrate preference, (2) geomorphic preference, (3) trophic ecology, (4) locomotion morphology, (5) reproductive strategy, and (6) stream size preference. Stream size categories included small streams, small, medium, and large rivers, and no size preference. The frequencies of each species trait category were determined for each stream size category based on life history information from the literature. Cluster analysis revealed the presence of covarying groups of species trait categories. One cluster (RUN) included the traits of planktivore and herbivore feeding ecology, migratory reproductive behavior and broadcast spawning, preferences for main-channel habitats, and a lack of preferences for substrate type. The frequencies of classifications for the RUN cluster varied significantly across stream size categories (P = 0.009), being greater for large rivers than for small streams and rivers. Another cluster (RIFFLE) included the traits of invertivore feeding ecology, simple nester reproductive behavior, a preference for riffles, and a preference for bedrock, boulder, and cobble-rubble substrate. No significant differences in the frequency of classifications among stream size categories were detected for the RIFFLE cluster (P = 0.328). Our results suggest that fish community function is structured by large-scale differences in habitat and is different for large rivers than for small streams and rivers. Our findings support theoretical predictions of variation in species traits among stream reaches based on ecological frameworks such as landscape filters, habitat templates, and the river continuum concept. We believe that the species trait classifications presented here provide an opportunity for further examination of fish species' relations to physical, chemical, and biological factors in lotic habitats ranging from small streams to large rivers.

Heterogeneity in phenotypes based on smoking status in the Great Lakes Smoker Sibling Registry.

PubMed

Pomerleau, Cynthia S; Pomerleau, Ovide F; Snedecor, Sandy M; Gaulrapp, Stefanie; Kardia, Sharon L R

2004-12-01

We investigated whether 52 same-sex sibling pairs discordant for ever-smoking differed on psychiatric cofactors, alcohol and caffeine use, and responses to initial exposure to smoking. Ever-smokers scored significantly higher on measures of novelty seeking, depression, and childhood ADHD, and on alcohol dependence, alcohol intake, and caffeine intake. They reported significantly more pleasurable experiences, dizziness, "buzz," and relaxation upon initial exposure to smoking and significantly fewer displeasurable sensations, nausea, and cough than did nicotine-exposed, never-smoking siblings. Ever-smokers had significantly fewer years of education than their never-smoking siblings, suggesting that the concentration of smokers in lower socioeconomic strata may be partly due to downward mobility among smokers, possibly because of the observed elevation in psychiatric cofactors, which may interfere with academic performance. These findings are consistent with differences previously identified in unrelated ever- and never-smokers. Because same-sex siblings typically share a large set of common environments during childhood, our findings could be due either to genetic differences among siblings and/or (excepting educational level and responses to early exposure) to differences in adult environments.

Electric Field Fluctuations in Water

NASA Astrophysics Data System (ADS)

Thorpe, Dayton; Limmer, David; Chandler, David

2013-03-01

Charge transfer in solution, such as autoionization and ion pair dissociation in water, is governed by rare electric field fluctuations of the solvent. Knowing the statistics of such fluctuations can help explain the dynamics of these rare events. Trajectories short enough to be tractable by computer simulation are virtually certain not to sample the large fluctuations that promote rare events. Here, we employ importance sampling techniques with classical molecular dynamics simulations of liquid water to study statistics of electric field fluctuations far from their means. We find that the distributions of electric fields located on individual water molecules are not in general gaussian. Near the mean this non-gaussianity is due to the internal charge distribution of the water molecule. Further from the mean, however, there is a previously unreported Bjerrum-like defect that stabilizes certain large fluctuations out of equilibrium. As expected, differences in electric fields acting between molecules are gaussian to a remarkable degree. By studying these differences, though, we are able to determine what configurations result not only in large electric fields, but also in electric fields with long spatial correlations that may be needed to promote charge separation.

A progress report on estuary modeling by the finite-element method

USGS Publications Warehouse

Gray, William G.

1978-01-01

Various schemes are investigated for finite-element modeling of two-dimensional surface-water flows. The first schemes investigated combine finite-element spatial discretization with split-step time stepping schemes that have been found useful in finite-difference computations. Because of the large number of numerical integrations performed in space and the large sparse matrices solved, these finite-element schemes were found to be economically uncompetitive with finite-difference schemes. A very promising leapfrog scheme is proposed which, when combined with a novel very fast spatial integration procedure, eliminates the need to solve any matrices at all. Additional problems attacked included proper propagation of waves and proper specification of the normal flow-boundary condition. This report indicates work in progress and does not come to a definitive conclusion as to the best approach for finite-element modeling of surface-water problems. The results presented represent findings obtained between September 1973 and July 1976. (Woodard-USGS)

Two-machine flow shop scheduling integrated with preventive maintenance planning

NASA Astrophysics Data System (ADS)

Wang, Shijin; Liu, Ming

2016-02-01

This paper investigates an integrated optimisation problem of production scheduling and preventive maintenance (PM) in a two-machine flow shop with time to failure of each machine subject to a Weibull probability distribution. The objective is to find the optimal job sequence and the optimal PM decisions before each job such that the expected makespan is minimised. To investigate the value of integrated scheduling solution, computational experiments on small-scale problems with different configurations are conducted with total enumeration method, and the results are compared with those of scheduling without maintenance but with machine degradation, and individual job scheduling combined with independent PM planning. Then, for large-scale problems, four genetic algorithm (GA) based heuristics are proposed. The numerical results with several large problem sizes and different configurations indicate the potential benefits of integrated scheduling solution and the results also show that proposed GA-based heuristics are efficient for the integrated problem.

Amyloid Polymorphism in the Protein Folding and Aggregation Energy Landscape.

PubMed

Adamcik, Jozef; Mezzenga, Raffaele

2018-02-15

Protein folding involves a large number of steps and conformations in which the folding protein samples different thermodynamic states characterized by local minima. Kinetically trapped on- or off-pathway intermediates are metastable folding intermediates towards the lowest absolute energy minima, which have been postulated to be the natively folded state where intramolecular interactions dominate, and the amyloid state where intermolecular interactions dominate. However, this view largely neglects the rich polymorphism found within amyloid species. We review the protein folding energy landscape in view of recent findings identifying specific transition routes among different amyloid polymorphs. Observed transitions such as twisted ribbon→crystal or helical ribbon→nanotube, and forbidden transitions such helical ribbon↛crystal, are discussed and positioned within the protein folding and aggregation energy landscape. Finally, amyloid crystals are identified as the ground state of the protein folding and aggregation energy landscape. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measures for a transdimensional multiverse

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

Schwartz-Perlov, Delia; Vilenkin, Alexander, E-mail: dperlov@cosmos.phy.tufts.edu, E-mail: vilenkin@cosmos.phy.tufts.edu

2010-06-01

The multiverse/landscape paradigm that has emerged from eternal inflation and string theory, describes a large-scale multiverse populated by ''pocket universes'' which come in a huge variety of different types, including different dimensionalities. In order to make predictions in the multiverse, we need a probability measure. In (3+1)d landscapes, the scale factor cutoff measure has been previously shown to have a number of attractive properties. Here we consider possible generalizations of this measure to a transdimensional multiverse. We find that a straightforward extension of scale factor cutoff to the transdimensional case gives a measure that strongly disfavors large amounts of slow-rollmore » inflation and predicts low values for the density parameter Ω, in conflict with observations. A suitable generalization, which retains all the good properties of the original measure, is the ''volume factor'' cutoff, which regularizes the infinite spacetime volume using cutoff surfaces of constant volume expansion factor.« less

Does sustained participation in an online health community affect sentiment?

PubMed

Zhang, Shaodian; Bantum, Erin; Owen, Jason; Elhadad, Noémie

2014-01-01

A large number of patients rely on online health communities to exchange information and psychosocial support with their peers. Examining participation in a community and its impact on members' behaviors and attitudes is one of the key open research questions in the field of study of online health communities. In this paper, we focus on a large public breast cancer community and conduct sentiment analysis on all its posts. We investigate the impact of different factors on post sentiment, such as time since joining the community, posting activity, age of members, and cancer stage of members. We find that there is a significant increase in sentiment of posts through time, with different patterns of sentiment trends for initial posts in threads and reply posts. Factors each play a role; for instance stage-IV members form a particular sub-community with patterns of sentiment and usage distinct from others members.

Direct Observation of Gold Nanoparticle Assemblies with the Porin MspA on Mica

PubMed Central

Basel, Matthew T.; Dani, Raj Kumar; Kang, Myungshim; Pavlenok, Mikhail; Chikan, Viktor; Smith, Paul E.; Niederweis, Michael

2009-01-01

The octameric porin MspA from Mycobacterium smegmatis is sufficiently stable to form a non-membrane-supported stand-alone porin on Mica surfaces. About 98% of all MspA octamers were found to stand upright on Mica, with their periplasmic loop regions bound to the hydrophilic Mica surface. Both, small (d = 3.7 nm) and large (d = 17 nm) gold nanoparticles bind to MspA, however in different positions: small gold nanoparticles bind within the MspA pore, whereas the large gold nanoparticles bind to the upper region of MspA. These experiments demonstrate that gold nanoparticles can be positioned at different, well-defined distances from the underlying surface using the MspA pore as a template. These findings represent a significant step towards the use of electrically insulating stable proteins in combination with metal nanoparticles in nanodevices. PMID:19236086

Equilibrium Strategy and Population-Size Effects in Lowest Unique Bid Auctions

NASA Astrophysics Data System (ADS)

Pigolotti, Simone; Bernhardsson, Sebastian; Juul, Jeppe; Galster, Gorm; Vivo, Pierpaolo

2012-02-01

In lowest unique bid auctions, N players bid for an item. The winner is whoever places the lowest bid, provided that it is also unique. We use a grand canonical approach to derive an analytical expression for the equilibrium distribution of strategies. We then study the properties of the solution as a function of the mean number of players, and compare them with a large data set of internet auctions. The theory agrees with the data with striking accuracy for small population-size N, while for larger N a qualitatively different distribution is observed. We interpret this result as the emergence of two different regimes, one in which adaptation is feasible and one in which it is not. Our results question the actual possibility of a large population to adapt and find the optimal strategy when participating in a collective game.

Everyone knows what is interesting: Salient locations which should be fixated

PubMed Central

Masciocchi, Christopher Michael; Mihalas, Stefan; Parkhurst, Derrick; Niebur, Ernst

2010-01-01

Most natural scenes are too complex to be perceived instantaneously in their entirety. Observers therefore have to select parts of them and process these parts sequentially. We study how this selection and prioritization process is performed by humans at two different levels. One is the overt attention mechanism of saccadic eye movements in a free-viewing paradigm. The second is a conscious decision process in which we asked observers which points in a scene they considered the most interesting. We find in a very large participant population (more than one thousand) that observers largely agree on which points they consider interesting. Their selections are also correlated with the eye movement pattern of different subjects. Both are correlated with predictions of a purely bottom–up saliency map model. Thus, bottom–up saliency influences cognitive processes as far removed from the sensory periphery as in the conscious choice of what an observer considers interesting. PMID:20053088

Trends of atmospheric circulation during singular hot days in Europe

NASA Astrophysics Data System (ADS)

Jézéquel, Aglaé; Cattiaux, Julien; Naveau, Philippe; Radanovics, Sabine; Ribes, Aurélien; Vautard, Robert; Vrac, Mathieu; Yiou, Pascal

2018-05-01

The influence of climate change on mid-latitudes atmospheric circulation is still very uncertain. The large internal variability makes it difficult to extract any statistically significant signal regarding the evolution of the circulation. Here we propose a methodology to calculate dynamical trends tailored to the circulation of specific days by computing the evolution of the distances between the circulation of the day of interest and the other days of the time series. We compute these dynamical trends for two case studies of the hottest days recorded in two different European regions (corresponding to the heat-waves of summer 2003 and 2010). We use the NCEP reanalysis dataset, an ensemble of CMIP5 models, and a large ensemble of a single model (CESM), in order to account for different sources of uncertainty. While we find a positive trend for most models for 2003, we cannot conclude for 2010 since the models disagree on the trend estimates.

Graphene growth with ‘no’ feedstock

NASA Astrophysics Data System (ADS)

Qing, Fangzhu; Jia, Ruitao; Li, Bao-Wen; Liu, Chunlin; Li, Congzhou; Peng, Bo; Deng, Longjiang; Zhang, Wanli; Li, Yanrong; Ruoff, Rodney S.; Li, Xuesong

2017-06-01

Synthesis of graphene by chemical vapor deposition (CVD) from hydrocarbons on Cu foil substrates can yield high quality and large area graphene films. In a typical CVD process, a hydrocarbon in the gas phase is introduced for graphene growth and hydrogen is usually required to achieve high quality graphene. We have found that in a low pressure CVD system equipped with an oil mechanical vacuum pump located downstream, graphene can be grown without deliberate introduction of a carbon feedstock but with only trace amounts of C present in the system, the origin of which we attribute to the vapor of the pump oil. This finding may help to rationalize the differences in graphene growth reported by different research groups. It should also help to gain an in-depth understanding of graphene growth mechanisms with the aim to improve the reproducibility and structure control in graphene synthesis, e.g. the formation of large area single crystal graphene and uniform bilayer graphene.

How the folding rates of two- and multistate proteins depend on the amino acid properties.

PubMed

Huang, Jitao T; Huang, Wei; Huang, Shanran R; Li, Xin

2014-10-01

Proteins fold by either two-state or multistate kinetic mechanism. We observe that amino acids play different roles in different mechanism. Many residues that are easy to form regular secondary structures (α helices, β sheets and turns) can promote the two-state folding reactions of small proteins. Most of hydrophilic residues can speed up the multistate folding reactions of large proteins. Folding rates of large proteins are equally responsive to the flexibility of partial amino acids. Other properties of amino acids (including volume, polarity, accessible surface, exposure degree, isoelectric point, and phase transfer energy) have contributed little to folding kinetics of the proteins. Cysteine is a special residue, it triggers two-state folding reaction and but inhibits multistate folding reaction. These findings not only provide a new insight into protein structure prediction, but also could be used to direct the point mutations that can change folding rate. © 2014 Wiley Periodicals, Inc.

Pebble Accretion in Turbulent Protoplanetary Disks

NASA Astrophysics Data System (ADS)

Xu, Ziyan; Bai, Xue-Ning; Murray-Clay, Ruth A.

2017-09-01

It has been realized in recent years that the accretion of pebble-sized dust particles onto planetary cores is an important mode of core growth, which enables the formation of giant planets at large distances and assists planet formation in general. The pebble accretion theory is built upon the orbit theory of dust particles in a laminar protoplanetary disk (PPD). For sufficiently large core mass (in the “Hill regime”), essentially all particles of appropriate sizes entering the Hill sphere can be captured. However, the outer regions of PPDs are expected to be weakly turbulent due to the magnetorotational instability (MRI), where turbulent stirring of particle orbits may affect the efficiency of pebble accretion. We conduct shearing-box simulations of pebble accretion with different levels of MRI turbulence (strongly turbulent assuming ideal magnetohydrodynamics, weakly turbulent in the presence of ambipolar diffusion, and laminar) and different core masses to test the efficiency of pebble accretion at a microphysical level. We find that accretion remains efficient for marginally coupled particles (dimensionless stopping time {τ }s˜ 0.1{--}1) even in the presence of strong MRI turbulence. Though more dust particles are brought toward the core by the turbulence, this effect is largely canceled by a reduction in accretion probability. As a result, the overall effect of turbulence on the accretion rate is mainly reflected in the changes in the thickness of the dust layer. On the other hand, we find that the efficiency of pebble accretion for strongly coupled particles (down to {τ }s˜ 0.01) can be modestly reduced by strong turbulence for low-mass cores.

Imprint of DES superstructures on the cosmic microwave background

DOE PAGES

Kovács, A.; Sánchez, C.; García-Bellido, J.; ...

2016-11-17

Here, small temperature anisotropies in the Cosmic Microwave Background can be sourced by density perturbations via the late-time integrated Sachs-Wolfe effect. Large voids and superclusters are excellent environments to make a localized measurement of this tiny imprint. In some cases excess signals have been reported. We probed these claims with an independent data set, using the first year data of the Dark Energy Survey in a different footprint, and using a different super-structure finding strategy. We identified 52 large voids and 102 superclusters at redshiftsmore » $0.2 < z < 0.65$. We used the Jubilee simulation to a priori evaluate the optimal ISW measurement configuration for our compensated top-hat filtering technique, and then performed a stacking measurement of the CMB temperature field based on the DES data. For optimal configurations, we detected a cumulative cold imprint of voids with $$\\Delta T_{f} \\approx -5.0\\pm3.7~\\mu K$$ and a hot imprint of superclusters $$\\Delta T_{f} \\approx 5.1\\pm3.2~\\mu K$$ ; this is $$\\sim1.2\\sigma$$ higher than the expected $$|\\Delta T_{f}| \\approx 0.6~\\mu K$$ imprint of such super-structures in $$\\Lambda$$CDM. If we instead use an a posteriori selected filter size ($$R/R_{v}=0.6$$), we can find a temperature decrement as large as $$\\Delta T_{f} \\approx -9.8\\pm4.7~\\mu K$$ for voids, which is $$\\sim2\\sigma$$ above $$\\Lambda$$CDM expectations and is comparable to previous measurements made using SDSS super-structure data.« less

Imprint of DES superstructures on the cosmic microwave background

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

Kovács, A.; Sánchez, C.; García-Bellido, J.

Here, small temperature anisotropies in the Cosmic Microwave Background can be sourced by density perturbations via the late-time integrated Sachs-Wolfe effect. Large voids and superclusters are excellent environments to make a localized measurement of this tiny imprint. In some cases excess signals have been reported. We probed these claims with an independent data set, using the first year data of the Dark Energy Survey in a different footprint, and using a different super-structure finding strategy. We identified 52 large voids and 102 superclusters at redshiftsmore » $0.2 < z < 0.65$. We used the Jubilee simulation to a priori evaluate the optimal ISW measurement configuration for our compensated top-hat filtering technique, and then performed a stacking measurement of the CMB temperature field based on the DES data. For optimal configurations, we detected a cumulative cold imprint of voids with $$\\Delta T_{f} \\approx -5.0\\pm3.7~\\mu K$$ and a hot imprint of superclusters $$\\Delta T_{f} \\approx 5.1\\pm3.2~\\mu K$$ ; this is $$\\sim1.2\\sigma$$ higher than the expected $$|\\Delta T_{f}| \\approx 0.6~\\mu K$$ imprint of such super-structures in $$\\Lambda$$CDM. If we instead use an a posteriori selected filter size ($$R/R_{v}=0.6$$), we can find a temperature decrement as large as $$\\Delta T_{f} \\approx -9.8\\pm4.7~\\mu K$$ for voids, which is $$\\sim2\\sigma$$ above $$\\Lambda$$CDM expectations and is comparable to previous measurements made using SDSS super-structure data.« less

3D radiative transfer effects in multi-angle/multispectral radio-polarimetric signals from a mixture of clouds and aerosols viewed by a non-imaging sensor

NASA Astrophysics Data System (ADS)

Davis, Anthony B.; Garay, Michael J.; Xu, Feng; Qu, Zheng; Emde, Claudia

2013-09-01

When observing a spatially complex mix of aerosols and clouds in a single relatively large field-of-view, nature entangles their signals non-linearly through polarized radiation transport processes that unfold in the 3D position and direction spaces. In contrast, any practical forward model in a retrieval algorithm will use only 1D vector radiative transfer (vRT) in a linear mixing technique. We assess the difference between the observed and predicted signals using synthetic data from a high-fidelity 3D vRT model with clouds generated using a Large Eddy Simulation model and an aerosol climatology. We find that this difference is signal—not noise—for the Aerosol Polarimetry Sensor (APS), an instrument developed by NASA. Moreover, the worst case scenario is also the most interesting case, namely, when the aerosol burden is large, hence hase the most impact on the cloud microphysics and dynamics. Based on our findings, we formulate a mitigation strategy for these unresolved cloud adjacency effects assuming that some spatial information is available about the structure of the clouds at higher resolution from "context" cameras, as was planned for NASA's ill-fated Glory mission that was to carry the APS but failed to reach orbit. Application to POLDER (POLarization and Directionality of Earth Reflectances) data from the period when PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) was in the A-train is briefly discussed.

3D Radiative Transfer Effects in Multi-Angle/Multi-Spectral Radio-Polarimetric Signals from a Mixture of Clouds and Aerosols Viewed by a Non-Imaging Sensor

NASA Technical Reports Server (NTRS)

Davis, Anthony B.; Garay, Michael J.; Xu, Feng; Qu, Zheng; Emde, Claudia

2013-01-01

When observing a spatially complex mix of aerosols and clouds in a single relatively large field-of-view, nature entangles their signals non-linearly through polarized radiation transport processes that unfold in the 3D position and direction spaces. In contrast, any practical forward model in a retrieval algorithm will use only 1D vector radiative transfer (vRT) in a linear mixing technique. We assess the difference between the observed and predicted signals using synthetic data from a high-fidelity 3D vRT model with clouds generated using a Large Eddy Simulation model and an aerosol climatology. We find that this difference is signal--not noise--for the Aerosol Polarimetry Sensor (APS), an instrument developed by NASA. Moreover, the worst case scenario is also the most interesting case, namely, when the aerosol burden is large, hence hase the most impact on the cloud microphysics and dynamics. Based on our findings, we formulate a mitigation strategy for these unresolved cloud adjacency effects assuming that some spatial information is available about the structure of the clouds at higher resolution from "context" cameras, as was planned for NASA's ill-fated Glory mission that was to carry the APS but failed to reach orbit. Application to POLDER (POLarization and Directionality of Earth Reflectances) data from the period when PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) was in the A-train is briefly discussed.

Measuring the universe with high-precision large-scale structure

NASA Astrophysics Data System (ADS)

Mehta, Kushal Tushar

Baryon acoustic oscillations (BAOs) are used to obtain precision measurements of cosmological parameters from large-scale surveys. While robust against most systematics, there are certain theoretical uncertainties that can affect BAO and galaxy clustering measurements. In this thesis I use data from the Sloan Digital Sky Survey (SDSS) to measure cosmological parameters and use N-body and smoothed-particle hydrodynamic (SPH) simulations to measure the effect of theoretical uncertainties by using halo occupation distributions (HODs). I investigate the effect of galaxy bias on BAO measurements by creating mock galaxy catalogs from large N-body simulations at z = 1. I find that there is no additional shift in the acoustic scale (0.10% +/- 0.10%) for the less biased HODs (b 3). I present the methodology and implementation of the simple one-step reconstruction technique introduced by Eisenstein et al. (2007) to biased tracers in N-body simulation. Reconstruction reduces the errorbars on the acoustic scale measurement by a factor of 1.5 - 2, and removes any additional shift due to galaxy bias for all HODs (0.07% +/- 0.15%) . Padmanabhan et al. (2012) and Xu et al. (2012) use this reconstruction technique in the SDSS DR7 data to measure DV (z = 0.35) (rsfidr s) = 1356 +/- 25 Mpc. Here I use this measurement in combination with measurements from the cosmic microwave background and the supernovae legacy survey to measure various cosmological parameters. I find the data consistent with the LambdaCDM Universe with a flat geometry. In particular, I measure H0 = 69.8 +/- 1.2 km/s/Mpc, w = 0.97 +/- 0.17, OK= -0.004 +/- 0.005 in the LambdaCDM, wCDM, and oCDM models respectively. Next, I measure the effect of large-scale (5 Mpc) halo environment density on the HOD by using an SPH simulation at z = 0, 0.35, 0.5, 0.75, 1.0$. I do not find any significant dependence of the HOD on the halo environment density for different galaxy mass thresholds, red and blue galaxies, and at different redshifts. I use the MultiDark N-body simualtion to measure the possible effect of environment density on the galaxy correlation function xi(r). I find that environment density enhances xi(r) by 3% at scales of 1 - 20 Mpc/h at z = 0 and up to 12% at 0.3 Mpc/h and 8% at 1 - 4 Mpc/h for z = 1.

The Impacts of Numerical Schemes on Asymmetric Hurricane Intensification

NASA Astrophysics Data System (ADS)

Guimond, S.; Reisner, J. M.; Marras, S.; Giraldo, F.

2015-12-01

The fundamental pathways for tropical cyclone (TC) intensification are explored by considering axisymmetric and asymmetric impulsive thermal perturbations to balanced, TC-like vortices using the dynamic cores of three different numerical models. Attempts at reproducing the results of previous work, which used the community atmospheric model WRF (Nolan and Grasso 2003; NG03), revealed a discrepancy with the impacts of purely asymmetric thermal forcing. The current study finds that thermal asymmetries can have an important, largely positive role on the vortex intensification whereas NG03 and other studies find that asymmetric impacts are negligible. Analysis of the spectral energetics of each numerical model indicates that the vortex response to asymmetric thermal perturbations is significantly damped in WRF relative to the other numerical models. Spectral kinetic energy budgets show that this anomalous damping is due to the increased removal of kinetic energy from the convergence of the vertical pressure flux, which is related to the flux of inertia-gravity wave energy. The increased kinetic energy in the other two models is shown to originate around the scales of the heating and propagate upscale with time. For very large thermal amplitudes (~ 50 K and above), the anomalous removal of kinetic energy due to inertia-gravity wave activity is much smaller resulting in little differences between models. The results of this paper indicate that the numerical treatment of small-scale processes that project strongly onto inertia-gravity wave energy are responsible for these differences, with potentially important impacts for the understanding and prediction of TC intensification.

Markov models for fMRI correlation structure: Is brain functional connectivity small world, or decomposable into networks?

PubMed

Varoquaux, G; Gramfort, A; Poline, J B; Thirion, B

2012-01-01

Correlations in the signal observed via functional Magnetic Resonance Imaging (fMRI), are expected to reveal the interactions in the underlying neural populations through hemodynamic response. In particular, they highlight distributed set of mutually correlated regions that correspond to brain networks related to different cognitive functions. Yet graph-theoretical studies of neural connections give a different picture: that of a highly integrated system with small-world properties: local clustering but with short pathways across the complete structure. We examine the conditional independence properties of the fMRI signal, i.e. its Markov structure, to find realistic assumptions on the connectivity structure that are required to explain the observed functional connectivity. In particular we seek a decomposition of the Markov structure into segregated functional networks using decomposable graphs: a set of strongly-connected and partially overlapping cliques. We introduce a new method to efficiently extract such cliques on a large, strongly-connected graph. We compare methods learning different graph structures from functional connectivity by testing the goodness of fit of the model they learn on new data. We find that summarizing the structure as strongly-connected networks can give a good description only for very large and overlapping networks. These results highlight that Markov models are good tools to identify the structure of brain connectivity from fMRI signals, but for this purpose they must reflect the small-world properties of the underlying neural systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

The spectral energy distribution of galaxies at z > 2.5: Implication from the Herschel/SPIRE color-color diagram

NASA Astrophysics Data System (ADS)

Yuan, Fangting; Buat, Veronique; Burgarella, Denis; Ciesla, Laure; Heinis, Sebastien; Shen, Shiyin; Shao, Zhengyi; Hou, Jinliang

2015-08-01

We use the Herschel SPIRE color-color diagram to study the spectral energy distribution (SED) and the redshift estimation of high-z galaxies. We collect a sample of 57 galaxies with spectroscopically confirmed redshifts and reliable flux measurements at redshift z=2.5-6.4, and compare their average SPIRE colors with SED templates from local and high-z libraries. We find that local SEDs are inconsistent with high-z observations. For the libraries of Chary & Elbaz (2001) and Dale & Helou (2002), the local calibrations of the parameters LIR and alpha need to be adjusted to around 1011Lsun and 1.5 to describe the average colors given by the observations. For high-z libraries, the templates of Magdis et al. (2012) can well describe the average colors of the observations at high redshift, justifying their assumption of an evolution of SED from z=0 to 3. Using the templates of Magdis et al. (2012), we defined color cuts to divide the SPIRE color-color diagram into different regions with different mean redshifts. We tested this method and two other color cut methods 500 micron risers and the method of Amblard et al. (2010) using a large sample of 786 Herschel-selected galaxies, and find that these color cut methods can separate the sample into populations with different mean redshifts, although the dispersion of redshifts in each population is quite large.

Why is infant mortality higher in boys than in girls? A new hypothesis based on preconception environment and evidence from a large sample of twins.

PubMed

Pongou, Roland

2013-04-01

Infant mortality is higher in boys than girls in most parts of the world. This has been explained by sex differences in genetic and biological makeup, with boys being biologically weaker and more susceptible to diseases and premature death. At the same time, recent studies have found that numerous preconception or prenatal environmental factors affect the probability of a baby being conceived male or female. I propose that these environmental factors also explain sex differences in mortality. I contribute a new methodology of distinguishing between child biology and preconception environment by comparing male-female differences in mortality across opposite-sex twins, same-sex twins, and all twins. Using a large sample of twins from sub-Saharan Africa, I find that both preconception environment and child biology increase the mortality of male infants, but the effect of biology is substantially smaller than the literature suggests. I also estimate the interacting effects of biology with some intrauterine and external environmental factors, including birth order within a twin pair, social status, and climate. I find that a twin is more likely to be male if he is the firstborn, born to an educated mother, or born in certain climatic conditions. Male firstborns are more likely to survive than female firstborns, but only during the neonatal period. Finally, mortality is not affected by the interactions between biology and climate or between biology and social status.

Disability differentials in educational attainment in England: primary and secondary effects.

PubMed

Chatzitheochari, Stella; Platt, Lucinda

2018-04-17

Childhood disability has been largely overlooked in social stratification and life course research. As a result, we know remarkably little about mechanisms behind well-documented disability differentials in educational outcomes. This study investigates educational transitions of disabled youth using data from the Longitudinal Study of Young People in England. We draw on social stratification literature on primary and secondary effects as well as that on stigma and labelling in order to explain disabled young people's educational outcomes. We find that disability differentials in transition rates to full-time academic upper secondary education and to university are largely the result of primary effects, reflected in differences in school performance between disabled and non-disabled young people. However, we also find evidence for secondary effects, with similarly achieving disabled young people less likely to pursue full-time academic upper secondary education compared to their non-disabled peers. We examine the extent to which these effects can be explained by disabled youth's suppressed educational expectations as well as their experiences of being bullied at school, which we link to the stigma experienced by disabled young people and their families. We find that educational expectations play an important role at crucial transitions in the English school system, while the effect of bullying is considerably smaller. By drawing attention to different social processes contributing to disability differentials in attainment, our study moves beyond medical models that implicitly assume a naturalized association of disability with poor educational outcomes, and demonstrates the parallels of disability with other ascriptive inequalities. © London School of Economics and Political Science 2018.

Frequent pauses in Escherichia coli flagella elongation revealed by single cell real-time fluorescence imaging.

PubMed

Zhao, Ziyi; Zhao, Yifan; Zhuang, Xiang-Yu; Lo, Wei-Chang; Baker, Matthew A B; Lo, Chien-Jung; Bai, Fan

2018-05-14

The bacterial flagellum is a large extracellular protein organelle that extrudes from the cell surface. The flagellar filament is assembled from tens of thousands of flagellin subunits that are exported through the flagellar type III secretion system. Here, we measure the growth of Escherichia coli flagella in real time and find that, although the growth rate displays large variations at similar lengths, it decays on average as flagella lengthen. By tracking single flagella, we show that the large variations in growth rate occur as a result of frequent pauses. Furthermore, different flagella on the same cell show variable growth rates with correlation. Our observations are consistent with an injection-diffusion model, and we propose that an insufficient cytoplasmic flagellin supply is responsible for the pauses in flagellar growth in E. coli.

Coming of Age in Spain: The Self-identification, Beliefs and Self-Esteem of the Second Generation1

PubMed Central

Portes, Alejandro; Vickstrom, Erik; Aparicio, Rosa

2013-01-01

We review the literature on determinants of ethnic/national self-identities and self-esteem as a prelude to examining these outcomes among a large, statistically representative sample of second generation adolescents in Madrid and Barcelona. While these psycho-social outcomes are malleable, they still represent important dimensions of immigrant adaptation and can have significant consequences both for individual mobility and collective mobilizations. Current theories are largely based on data from the USA and other Anglophone countries. The availability of a new large Spanish survey allows us to test those theories in an entirely different socio-cultural context. The analysis concludes with a structural equations model that summarizes key determinants of national identities and self-esteem among children of immigrants in Spain. Theoretical and practical implications of these findings are discussed. PMID:21899520

Anomalous pressure dependence of thermal conductivities of large mass ratio compounds

DOE PAGES

Lindsay, Lucas R; Broido, David A.; Carrete, Jesus; ...

2015-03-27

The lattice thermal conductivities (k) of binary compound materials are examined as a function of hydrostatic pressure P using a first-principles approach. Compound materials with relatively small mass ratios, such as MgO, show an increase in k with P, consistent with measurements. Conversely, compounds with large mass ratios (e.g., BSb, BAs, BeTe, BeSe) exhibit decreasing with increasing P, a behavior that cannot be understood using simple theories of k. This anomalous P dependence of k arises from the fundamentally different nature of the intrinsic scattering processes for heat-carrying acoustic phonons in large mass ratio compounds compared to those with smallmore » mass ratios. We find this work demonstrates the power of first principles methods for thermal properties and advances the understanding of thermal transport in non-metals.« less

Anomalously large isotope effect in the glass transition of water

DOE PAGES

Gainaru, Catalin; Agapov, Alexander L.; Fuentes-Landete, Violeta; ...

2014-11-24

Here we present the discovery of an unusually large isotope effect in the structural relaxation and the glass transition temperature T g of water. Dielectric relaxation spectroscopy of low-density as well as of vapor deposited amorphous water reveal T g differences of 10±2K between H 2O and D 2O, sharply contrasting with other hydrogen bonded liquids for which H/D exchange increases T g by typically less than 1K. We show that the large isotope effect and the unusual variation of relaxation times in water at low temperatures can be explained in terms of quantum effects. Thus, our findings shed newmore » light on water's peculiar low-temperature dynamics and the possible role of quantum effects in its structural relaxation, and possibly in dynamics of other low molecular weight liquids.« less

Expression profile of Lgi1 gene in mouse brain during development.

PubMed

Ribeiro, Patrícia A O; Sbragia, Lourenço; Gilioli, Rovilson; Langone, Francesco; Conte, Fábio F; Lopes-Cendes, Iscia

2008-07-01

Mutations in LGI1 were described in patients with autosomal dominant partial epilepsy with auditory features (ADPEAF), and recent clinical findings have implicated LGI1 in human brain development. However, the precise role of LGI1 in epileptogenesis remains largely unknown. The objective of this study was to determine the expression pattern of Lgi1 in mice brain during development and in adult animals. Real-time polymerase chain reaction (PCR) quantification and Western blot experiments showed a relative low expression during intrauterine stages, increasing until adulthood. In addition, we did not find significant differences between left and right hemispheres. The hippocampus presented higher levels of Lgi1 expression when compared to the neocortex and the cerebellum of adult animals; however, these results did not reach statistical significance. This study was the first to determine a specific profile of Lgi1 gene expression during central nervous system development, which suggests a possible inhibitory function in latter stages of development. In addition, we did not find differences in hemispheric expression that could explain the predominance of left-sided abnormalities in patients with ADPEAF.

Who gives? Multilevel effects of gender and ethnicity on workplace charitable giving.

PubMed

Leslie, Lisa M; Snyder, Mark; Glomb, Theresa M

2013-01-01

Research on diversity in organizations has largely focused on the implications of gender and ethnic differences for performance, to the exclusion of other outcomes. We propose that gender and ethnic differences also have implications for workplace charitable giving, an important aspect of corporate social responsibility. Drawing from social role theory, we hypothesize and find that gender has consistent effects across levels of analysis; women donate more money to workplace charity than do men, and the percentage of women in a work unit is positively related to workplace charity, at least among men. Alternatively and consistent with social exchange theory, we hypothesize and find that ethnicity has opposing effects across levels of analysis; ethnic minorities donate less money to workplace charity than do Whites, but the percentage of minorities in a work unit is positively related to workplace charity, particularly among minorities. The findings provide a novel perspective on the consequences of gender and ethnic diversity in organizations and highlight synergies between organizational efforts to increase diversity and to build a reputation for corporate social responsibility. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Rates of climatic niche evolution are correlated with species richness in a large and ecologically diverse radiation of songbirds.

PubMed

Title, Pascal O; Burns, Kevin J

2015-05-01

By employing a recently inferred phylogeny and museum occurrence records, we examine the relationship of ecological niche evolution to diversification in the largest family of songbirds, the tanagers (Thraupidae). We test whether differences in species numbers in the major clades of tanagers can be explained by differences in rate of climatic niche evolution. We develop a methodological pipeline to process and filter occurrence records. We find that, of the ecological variables examined, clade richness is higher in clades with higher climatic niche rate, and that this rate is also greater for clades that occupy a greater extent of climatic space. Additionally, we find that more speciose clades contain species with narrower niche breadths, suggesting that clades in which species are more successful at diversifying across climatic gradients have greater potential for speciation or are more buffered from the risk of extinction. © 2015 John Wiley & Sons Ltd/CNRS.

Conservatives report, but liberals display, greater happiness.

PubMed

Wojcik, Sean P; Hovasapian, Arpine; Graham, Jesse; Motyl, Matt; Ditto, Peter H

2015-03-13

Research suggesting that political conservatives are happier than political liberals has relied exclusively on self-report measures of subjective well-being. We show that this finding is fully mediated by conservatives' self-enhancing style of self-report (study 1; N = 1433) and then describe three studies drawing from "big data" sources to assess liberal-conservative differences in happiness-related behavior (studies 2 to 4; N = 4936). Relative to conservatives, liberals more frequently used positive emotional language in their speech and smiled more intensely and genuinely in photographs. Our results were consistent across large samples of online survey takers, U.S. politicians, Twitter users, and LinkedIn users. Our findings illustrate the nuanced relationship between political ideology, self-enhancement, and happiness and illuminate the contradictory ways that happiness differences can manifest across behavior and self-reports. Copyright © 2015, American Association for the Advancement of Science.

Quantitative patterns of stylistic influence in the evolution of literature.

PubMed

Hughes, James M; Foti, Nicholas J; Krakauer, David C; Rockmore, Daniel N

2012-05-15

Literature is a form of expression whose temporal structure, both in content and style, provides a historical record of the evolution of culture. In this work we take on a quantitative analysis of literary style and conduct the first large-scale temporal stylometric study of literature by using the vast holdings in the Project Gutenberg Digital Library corpus. We find temporal stylistic localization among authors through the analysis of the similarity structure in feature vectors derived from content-free word usage, nonhomogeneous decay rates of stylistic influence, and an accelerating rate of decay of influence among modern authors. Within a given time period we also find evidence for stylistic coherence with a given literary topic, such that writers in different fields adopt different literary styles. This study gives quantitative support to the notion of a literary "style of a time" with a strong trend toward increasingly contemporaneous stylistic influence.

Coming to terms about describing Golden Eagle reproduction

USGS Publications Warehouse

Steenhof, Karen; Kochert, Michael N.; McIntyre, Carol L.; Brown, Jessi L.

2017-01-01

Clearly defined terms are essential for reporting and understanding research findings, and inconsistent terminology can complicate efforts to compare findings from different studies. In this article, we reiterate and clarify recommended terms for describing Golden Eagle (Aquila chrysaetos) territory occupancy and reproduction. Several authors have provided recommendations for reporting data on raptor reproduction, but our literature review showed that authors continue to use different, often ambiguous and undefined, terms. The inconsistent use of terminology by researchers has been continued and expanded by lawmakers, regulators, and managers, perpetuating confusion. We recommend that authors clearly define and reference all terminology that they use, and we caution against use of the term “active” to describe a nest or nesting territory, because it is tainted with a history of inconsistent use. We provide a glossary of recommended terms for Golden Eagles and other large, long-lived raptors.

Diffusion of environmentally-friendly energy technologies: buy versus lease differences in residential PV markets

NASA Astrophysics Data System (ADS)

Rai, Varun; Sigrin, Benjamin

2013-03-01

Diffusion of microgeneration technologies, particularly rooftop photovoltaic (PV), represents a key option in reducing emissions in the residential sector. We use a uniquely rich dataset from the burgeoning residential PV market in Texas to study the nature of the consumer’s decision-making process in the adoption of these technologies. In particular, focusing on the financial metrics and the information decision-makers use to base their decisions upon, we study how the leasing and buying models affect individual choices and, thereby, the adoption of capital-intensive energy technologies. Overall, our findings suggest that the leasing model more effectively addresses consumers’ informational requirements and that, contrary to some other studies, buyers and lessees of PV do not necessarily differ significantly along socio-demographic variables. Instead, we find that the leasing model has opened up the residential PV market to a new, and potentially very large, consumer segment—those with a tight cash-flow situation.

Multiple impacts of epilepsy and contributing factors: findings from an ethnographic study in Vietnam

PubMed Central

Aydemir, Nuran; Vu Trung, Dang; Snape, Dee; Baker, Gus A; Jacoby, Ann

2009-01-01

We investigated issues related to treatment, impact of epilepsy, attitudes toward epilepsy and disclosure in Vietnam by using in depth interviews with people with epilepsy (PWE) and their family members. We found that although participants prefer Western treatment methods more than traditional ones, they experience problems in accessing different kinds of anti-epileptic drugs (AEDs) and higher-level treatment facilities and with respect to treatment expenses. The impact of epilepsy can be observed in a wide range of daily living activities which include working, education, marriage prospects and family formation. Although both families and society at large do not hold negative attitudes toward epilepsy, most PWE reported a sense of burden to others. Both PWE and family members generally prefer disclosing epilepsy rather than concealing it from others. Our findings strongly suggest a need for different types of AEDs, and supporting information for PWE, family members and general public about epilepsy. PMID:19800851

NNLO QCD corrections to production of a spin-2 particle with nonuniversal couplings in the Drell-Yan process

NASA Astrophysics Data System (ADS)

Banerjee, Pulak; Dhani, Prasanna K.; Kumar, M. C.; Mathews, Prakash; Ravindran, V.

2018-05-01

We study the phenomenological impact of the interaction of spin-2 fields with those of the Standard Model in a model independent framework up to next-to-next-to-leading order in perturbative quantum chromodynamics. We use the invariant mass distribution of the pair of leptons produced at the Large Hadron Collider to demonstrate this. A minimal scenario where the spin-2 fields couple to two gauge invariant operators with different coupling strengths has been considered. These operators not being conserved show very different ultraviolet behavior increasing the searches options of spin-2 particles at the colliders. We find that our results using the higher order quantum corrections stabilize the predictions with respect to renormalization and factorization scales. We also find that corrections are appreciable which need to be taken into account in such searches at the colliders.

Absorption line profiles in a companion spectrum of a mass losing cool supergiant

NASA Technical Reports Server (NTRS)

Rodrigues, Liliya L.; Boehm-Vitense, Erika

1990-01-01

Cool star winds can best be observed in resonance absorption lines seen in the spectrum of a hot companion, due to the wind passing in front of the blue star. We calculated absorption line profiles that would be seen in the ultraviolet part of the blue companion spectrum. Line profiles are derived for different radial dependences of the cool star wind and for different orbital phases of the binary. Bowen and Wilson find theoretically that stellar pulsations drive mass loss. We therefore apply our calculations to the Cepheid binary S Muscae which has a B5V companion. We find an upper limit for the Cepheid mass loss of M less than or equal to 7 x 10(exp -10) solar mass per year provided that the stellar wind of the companion does not influence the Cepheid wind at large distances.

Evaluating the phase diagram of superconductors with asymmetric spin populations

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

Mannarelli, Massimo; Nardulli, Giuseppe; Ruggieri, Marco

2006-09-15

The phase diagram of a nonrelativistic fermionic system with imbalanced state populations interacting via a short-range S-wave attractive interaction is analyzed in the mean-field approximation. We determine the energetically favored state for different values of the mismatch between the two Fermi spheres in the weak- and strong-coupling regimes considering both homogeneous and nonhomogeneous superconductive states. We find that the homogeneous superconductive phase persists for values of the population imbalance that increase with increasing coupling strength. In the strong-coupling regime and for large population differences the energetically stable homogeneous phase is characterized by one gapless mode. We also find that themore » inhomogeneous superconductive phase characterized by the condensate {delta}(x){approx}{delta} exp(iq{center_dot}x) is energetically favored in a range of values of the chemical-potential mismatch that shrinks to zero in the strong-coupling regime.« less

Vector and tensor contributions to the curvature perturbation at second order

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

Carrilho, Pedro; Malik, Karim A., E-mail: p.gregoriocarrilho@qmul.ac.uk, E-mail: k.malik@qmul.ac.uk

2016-02-01

We derive the evolution equation for the second order curvature perturbation using standard techniques of cosmological perturbation theory. We do this for different definitions of the gauge invariant curvature perturbation, arising from different splits of the spatial metric, and compare the expressions. The results are valid at all scales and include all contributions from scalar, vector and tensor perturbations, as well as anisotropic stress, with all our results written purely in terms of gauge invariant quantities. Taking the large-scale approximation, we find that a conserved quantity exists only if, in addition to the non-adiabatic pressure, the transverse traceless part ofmore » the anisotropic stress tensor is also negligible. We also find that the version of the gauge invariant curvature perturbation which is exactly conserved is the one defined with the determinant of the spatial part of the inverse metric.« less

Mandatory universal drug plan, access to health care and health: Evidence from Canada.

PubMed

Wang, Chao; Li, Qing; Sweetman, Arthur; Hurley, Jeremiah

2015-12-01

This paper examines the impacts of a mandatory, universal prescription drug insurance program on health care utilization and health outcomes in a public health care system with free physician and hospital services. Using the Canadian National Population Health Survey from 1994 to 2003 and implementing a difference-in-differences estimation strategy, we find that the mandatory program substantially increased drug coverage among the general population. The program also increased medication use and general practitioner visits but had little effect on specialist visits and hospitalization. Findings from quantile regressions suggest that there was a large improvement in the health status of less healthy individuals. Further analysis by pre-policy drug insurance status and the presence of chronic conditions reveals a marked increase in the probability of taking medication and visiting a general practitioner among the previously uninsured and those with a chronic condition. Copyright © 2015 Elsevier B.V. All rights reserved.

Clustering Scientific Publications Based on Citation Relations: A Systematic Comparison of Different Methods.

PubMed

Šubelj, Lovro; van Eck, Nees Jan; Waltman, Ludo

2016-01-01

Clustering methods are applied regularly in the bibliometric literature to identify research areas or scientific fields. These methods are for instance used to group publications into clusters based on their relations in a citation network. In the network science literature, many clustering methods, often referred to as graph partitioning or community detection techniques, have been developed. Focusing on the problem of clustering the publications in a citation network, we present a systematic comparison of the performance of a large number of these clustering methods. Using a number of different citation networks, some of them relatively small and others very large, we extensively study the statistical properties of the results provided by different methods. In addition, we also carry out an expert-based assessment of the results produced by different methods. The expert-based assessment focuses on publications in the field of scientometrics. Our findings seem to indicate that there is a trade-off between different properties that may be considered desirable for a good clustering of publications. Overall, map equation methods appear to perform best in our analysis, suggesting that these methods deserve more attention from the bibliometric community.

Clustering Scientific Publications Based on Citation Relations: A Systematic Comparison of Different Methods

PubMed Central

Šubelj, Lovro; van Eck, Nees Jan; Waltman, Ludo

2016-01-01

Clustering methods are applied regularly in the bibliometric literature to identify research areas or scientific fields. These methods are for instance used to group publications into clusters based on their relations in a citation network. In the network science literature, many clustering methods, often referred to as graph partitioning or community detection techniques, have been developed. Focusing on the problem of clustering the publications in a citation network, we present a systematic comparison of the performance of a large number of these clustering methods. Using a number of different citation networks, some of them relatively small and others very large, we extensively study the statistical properties of the results provided by different methods. In addition, we also carry out an expert-based assessment of the results produced by different methods. The expert-based assessment focuses on publications in the field of scientometrics. Our findings seem to indicate that there is a trade-off between different properties that may be considered desirable for a good clustering of publications. Overall, map equation methods appear to perform best in our analysis, suggesting that these methods deserve more attention from the bibliometric community. PMID:27124610

Seebeck Effects in N-Type and P-Type Polymers Driven Simultaneously by Surface Polarization and Entropy Differences Based on Conductor/Polymer/Conductor Thin-Film Devices

DOE PAGES

Hu, Dehua; Liu, Qing; Tisdale, Jeremy; ...

2015-04-15

This paper reports Seebeck effects driven by both surface polarization difference and entropy difference by using intramolecular charge-transfer states in n-type and p-type conjugated polymers, namely IIDT and IIDDT, based on vertical conductor/polymer/conductor thin-film devices. Large Seebeck coefficients of -898 V/K and 1300 V/K from are observed from n-type IIDT p-type IIDDT, respectively, when the charge-transfer states are generated by a white light illumination of 100 mW/cm2. Simultaneously, electrical conductivities are increased from almost insulating states in dark condition to conducting states under photoexcitation in both n-type IIDT and p-type IIDDT devices. We find that the intramolecular charge-transfer states canmore » largely enhance Seebeck effects in the n-type IIDT and p-type IIDDT devices driven by both surface polarization difference and entropy difference. Furthermore, the Seebeck effects can be shifted between polarization and entropy regimes when electrical conductivities are changed. This reveals a new concept to develop Seebeck effects by controlling polarization and entropy regimes based on charge-transfer states in vertical conductor/polymer/conductor thin-film devices.« less

Effects of Seed Predators of Different Body Size on Seed Mortality in Bornean Logged Forest

PubMed Central

Hautier, Yann; Saner, Philippe; Philipson, Christopher; Bagchi, Robert; Ong, Robert C.; Hector, Andy

2010-01-01

Background The Janzen-Connell hypothesis proposes that seed and seedling enemies play a major role in maintaining high levels of tree diversity in tropical forests. However, human disturbance may alter guilds of seed predators including their body size distribution. These changes have the potential to affect seedling survival in logged forest and may alter forest composition and diversity. Methodology/Principal Findings We manipulated seed density in plots beneath con- and heterospecific adult trees within a logged forest and excluded vertebrate predators of different body sizes using cages. We show that small and large-bodied predators differed in their effect on con- and heterospecific seedling mortality. In combination small and large-bodied predators dramatically decreased both con- and heterospecific seedling survival. In contrast, when larger-bodied predators were excluded small-bodied predators reduced conspecific seed survival leaving seeds coming from the distant tree of a different species. Conclusions/Significance Our results suggest that seed survival is affected differently by vertebrate predators according to their body size. Therefore, changes in the body size structure of the seed predator community in logged forests may change patterns of seed mortality and potentially affect recruitment and community composition. PMID:20657841

The potential impact of immunization campaign budget re-allocation on global eradication of paediatric infectious diseases

PubMed Central

2011-01-01

Background The potential benefits of coordinating infectious disease eradication programs that use campaigns such as supplementary immunization activities (SIAs) should not be over-looked. One example of a coordinated approach is an adaptive "sequential strategy": first, all annual SIA budget is dedicated to the eradication of a single infectious disease; once that disease is eradicated, the annual SIA budget is re-focussed on eradicating a second disease, etc. Herd immunity suggests that a sequential strategy may eradicate several infectious diseases faster than a non-adaptive "simultaneous strategy" of dividing annual budget equally among eradication programs for those diseases. However, mathematical modeling is required to understand the potential extent of this effect. Methods Our objective was to illustrate how budget allocation strategies can interact with the nonlinear nature of disease transmission to determine time to eradication of several infectious diseases under different budget allocation strategies. Using a mathematical transmission model, we analyzed three hypothetical vaccine-preventable infectious diseases in three different countries. A central decision-maker can distribute funding among SIA programs for these three diseases according to either a sequential strategy or a simultaneous strategy. We explored the time to eradication under these two strategies under a range of scenarios. Results For a certain range of annual budgets, all three diseases can be eradicated relatively quickly under the sequential strategy, whereas eradication never occurs under the simultaneous strategy. However, moderate changes to total SIA budget, SIA frequency, order of eradication, or funding disruptions can create disproportionately large differences in the time and budget required for eradication under the sequential strategy. We find that the predicted time to eradication can be very sensitive to small differences in the rate of case importation between the countries. We also find that the time to eradication of all three diseases is not necessarily lowest when the least transmissible disease is targeted first. Conclusions Relatively modest differences in budget allocation strategies in the near-term can result in surprisingly large long-term differences in time required to eradicate, as a result of the amplifying effects of herd immunity and the nonlinearities of disease transmission. More sophisticated versions of such models may be useful to large international donors or other organizations as a planning or portfolio optimization tool, where choices must be made regarding how much funding to dedicate to different infectious disease eradication efforts. PMID:21955853

The potential impact of immunization campaign budget re-allocation on global eradication of paediatric infectious diseases.

PubMed

Fitzpatrick, Tiffany; Bauch, Chris T

2011-09-28

The potential benefits of coordinating infectious disease eradication programs that use campaigns such as supplementary immunization activities (SIAs) should not be over-looked. One example of a coordinated approach is an adaptive "sequential strategy": first, all annual SIA budget is dedicated to the eradication of a single infectious disease; once that disease is eradicated, the annual SIA budget is re-focussed on eradicating a second disease, etc. Herd immunity suggests that a sequential strategy may eradicate several infectious diseases faster than a non-adaptive "simultaneous strategy" of dividing annual budget equally among eradication programs for those diseases. However, mathematical modeling is required to understand the potential extent of this effect. Our objective was to illustrate how budget allocation strategies can interact with the nonlinear nature of disease transmission to determine time to eradication of several infectious diseases under different budget allocation strategies. Using a mathematical transmission model, we analyzed three hypothetical vaccine-preventable infectious diseases in three different countries. A central decision-maker can distribute funding among SIA programs for these three diseases according to either a sequential strategy or a simultaneous strategy. We explored the time to eradication under these two strategies under a range of scenarios. For a certain range of annual budgets, all three diseases can be eradicated relatively quickly under the sequential strategy, whereas eradication never occurs under the simultaneous strategy. However, moderate changes to total SIA budget, SIA frequency, order of eradication, or funding disruptions can create disproportionately large differences in the time and budget required for eradication under the sequential strategy. We find that the predicted time to eradication can be very sensitive to small differences in the rate of case importation between the countries. We also find that the time to eradication of all three diseases is not necessarily lowest when the least transmissible disease is targeted first. Relatively modest differences in budget allocation strategies in the near-term can result in surprisingly large long-term differences in time required to eradicate, as a result of the amplifying effects of herd immunity and the nonlinearities of disease transmission. More sophisticated versions of such models may be useful to large international donors or other organizations as a planning or portfolio optimization tool, where choices must be made regarding how much funding to dedicate to different infectious disease eradication efforts.