748 research outputs found
Marriage and cohabitation in the United States: the effects of union type on relationship quality.
Using national dyadic data from the 2010 Married and Cohabiting Couples (MCC) survey, I examine the effects on relationship quality of union type: âdirect marriageâ, âmarriage after cohabitingâ, âcohabitation with plans to marryâ, âcohabitation with no marriage planâ. In addition, I examine whether these effects are different for men and women. Consistent with prior research, I found that cohabitors without plans to marry report the lowest levels of relationship quality and those who married directly report the highest levels of relationship quality. Also consistent with prior research, I find no gendered differences in the effect of union type on relationship quality for those who are married. However, in cohabiting union, the effects of union type on relationship quality are stronger for women than for men. This study adds to the growing literature by showing that the effects of union type on relationship quality are gendered for cohabiting relationships
Intra-urban differentials in child health
This paper uses DHS data on the urban populations of Ghana, Egypt, Brazil and Thailand to investigate the effect of poverty and environmental conditions on diarrhoeal disease, nutritional status and survival among children. Differentials in health are moderate in urban Ghana, whereas in Egypt and Brazil reductions in morbidity and, above all, mortality have accrued largely to the better off. In Thailand, the poor fare better and inequalities in mortality are no larger than those in morbidity. Childrenâs health is affected by environmental conditions as well as by their familyâs socio-economic status
Spin-orbit coupling and the conservation of angular momentum
In nonrelativistic quantum mechanics, the total (i.e. orbital plus spin)
angular momentum of a charged particle with spin that moves in a Coulomb plus
spin-orbit-coupling potential is conserved. In a classical nonrelativistic
treatment of this problem, in which the Lagrange equations determine the
orbital motion and the Thomas equation yields the rate of change of the spin,
the particle's total angular momentum in which the orbital angular momentum is
defined in terms of the kinetic momentum is generally not conserved. However, a
generalized total angular momentum, in which the orbital part is defined in
terms of the canonical momentum, is conserved. This illustrates the fact that
the quantum-mechanical operator of momentum corresponds to the canonical
momentum of classical mechanics.Comment: 10 pages, as published by Eur. J. Phy
GEO Label Web Services for Dynamic and Effective Communication of Geospatial Metadata Quality
We present demonstrations of the GEO label Web services and their integration into a prototype extension of the GEOSS portal (http://scgeoviqua.sapienzaconsulting.com/web/guest/geo_home), the GMU portal (http://gis.csiss.gmu.edu/GADMFS/) and a GeoNetwork catalog application (http://uncertdata.aston.ac.uk:8080/geonetwork/srv/eng/main.home). The GEO label is designed to communicate, and facilitate interrogation of, geospatial quality information with a view to supporting efficient and effective dataset selection on the basis of quality, trustworthiness and fitness for use. The GEO label which we propose was developed and evaluated according to a user-centred design (UCD) approach in order to maximise the likelihood of user acceptance once deployed. The resulting label is dynamically generated from producer metadata in ISO or FDGC format, and incorporates user feedback on dataset usage, ratings and discovered issues, in order to supply a highly informative summary of metadata completeness and quality. The label was easily incorporated into a community portal as part of the GEO Architecture Implementation Programme (AIP-6) and has been successfully integrated into a prototype extension of the GEOSS portal, as well as the popular metadata catalog and editor, GeoNetwork. The design of the GEO label was based on 4 user studies conducted to: (1) elicit initial user requirements; (2) investigate initial user views on the concept of a GEO label and its potential role; (3) evaluate prototype label visualizations; and (4) evaluate and validate physical GEO label prototypes. The results of these studies indicated that users and producers support the concept of a label with drill-down interrogation facility, combining eight geospatial data informational aspects, namely: producer profile, producer comments, lineage information, standards compliance, quality information, user feedback, expert reviews, and citations information. These are delivered as eight facets of a wheel-like label, which are coloured according to metadata availability and are clickable to allow a user to engage with the original metadata and explore specific aspects in more detail. To support this graphical representation and allow for wider deployment architectures we have implemented two Web services, a PHP and a Java implementation, that generate GEO label representations by combining producer metadata (from standard catalogues or other published locations) with structured user feedback. Both services accept encoded URLs of publicly available metadata documents or metadata XML files as HTTP POST and GET requests and apply XPath and XSLT mappings to transform producer and feedback XML documents into clickable SVG GEO label representations. The label and services are underpinned by two XML-based quality models. The first is a producer model that extends ISO 19115 and 19157 to allow fuller citation of reference data, presentation of pixel- and dataset- level statistical quality information, and encoding of 'traceability' information on the lineage of an actual quality assessment. The second is a user quality model (realised as a feedback server and client) which allows reporting and query of ratings, usage reports, citations, comments and other domain knowledge. Both services are Open Source and are available on GitHub at https://github.com/lushv/geolabel-service and https://github.com/52North/GEO-label-java. The functionality of these services can be tested using our GEO label generation demos, available online at http://www.geolabel.net/demo.html and http://geoviqua.dev.52north.org/glbservice/index.jsf
Inference of selection gradients using performance measures as fitness proxies
O.D.F. is supported by the Natural Sciences and Engineering Research Council of Canada and the Madame VigdĂs FinnbogadĂłttir Scholarship. M.B.M. is supported by a University Research Fellowship from the Royal Society (London).1. Selection coefficients, i.e., selection differentials and gradients, are useful for quantifying selection and for making comparisons across traits and organisms, because they appear in known equations for relating selection and genetic variation to one another and to evolutionary change. However, selection coefficients can only be estimated in organisms where traits and fitness (components) can be measured. This is probably a major contributor to taxonomic biases of selection studies. Aspects of organismal performance, i.e., quantities that are likely to be positively related to fitness components, such as body size, are sometimes used as proxies for fitness, i.e., used in place of fitness components in regression-based selection analysis. To date, little theory exists to inform empirical studies about whether such procedures may yield selection coefficients with known relationships to genetic variation and evolution. 2. We show that the conditions under which performance measures can be used as proxies for fitness are very limited. Such analyses require that the regression of fitness on the proxy is linear and goes through the origin. We illustrate how fitness proxies may be used in conjunction with information about the performance-fitness relationship, and clarify how this is different from substituting fitness proxies for fitness components in selection analyses. 3. We apply proxy-based and fitness component-based selection analysis to a system where traits, a performance measure (size; similar to proxies that are commonly used in place of fitness), and a more proximate fitness measure, are all available on the same set of individuals. We find that proxy-based selection gradients are poorly reflective of selection gradients estimated using fitness components, even when proxy-fitness relationships are quite strong and reasonably linear. 4. We discuss the implications for proxy-based selection analysis. We emphasise that measures of organismal performance, such as size, may in many cases provide useful information that can contribute to quantitative inferences about natural selection, and their use could allow quantitative inference about selection to be conducted in a wider range of taxa. However, such inferences require quantitative analysis of both trait-performance and performance-fitness relationships, rather than substitution of performance for measures of fitness or fitness components.PostprintPeer reviewe
UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY PRELIMINARY GEOLOGIC MAP OF THE PILOT PEAK AND ADJACENT QUADRANGLES, ELKO COUNTY, NEVADA, AND BOX ELDER COUNTY, UTAH
genenames.org: the HGNC resources in 2011
The HUGO Gene Nomenclature Committee (HGNC) aims to assign a unique gene symbol and name to every human gene. The HGNC database currently contains almost 30â000 approved gene symbols, over 19â000 of which represent protein-coding genes. The public website, www.genenames.org, displays all approved nomenclature within Symbol Reports that contain data curated by HGNC editors and links to related genomic, phenotypic and proteomic information. Here we describe improvements to our resources, including a new Quick Gene Search, a new List Search, an integrated HGNC BioMart and a new Statistics and Downloads facility
Effects of dyslexia on postural control in adults
This is an accepted manuscript of an article published by Wiley in Dyslexia on 01/02/2010, available online: https://doi.org/10.1002/dys.398
The accepted version of the publication may differ from the final published version.Dyslexia has been shown to affect postural control. The aim of the present study was to investigate the difference in postural stability measured as torque variance in an adult dyslexic group (n =14, determined using the Adult Dyslexia Checklist (ADCL) and nonsense word repetition test) and an adult nonâdyslexic group (n =39) on a firm surface and on a foam block and with eyes open and eyes closed. Another aim was to investigate the correlation between ADCL scores and postural stability.
Findings showed that ADCL scores correlated with torque variance in the anteroposterior direction on foam with eyes closed (p =0.001) and in the lateral direction on the foam surface with eyes closed (p =0.040) and open (p =0.010). General Linear Model analysis showed that high dyslexia scores were associated with increased torque variance (p <0.001). However, we found no significant difference between dyslexics and nonâdyslexics, though there were indications of larger torque variance in the dyslexics.
The findings suggest that adults with high dyslexic ADCL scores may experience subâclinical balance deficits. Hence, assessing motor ability and postural control in those with high ADCL scores is motivated. Copyright © 2010 John Wiley & Sons, Ltd.Published versio
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