329 research outputs found
Change of nuclear configurations in the neutrinoless double- decay of Te Xe and Xe Ba
The change in the configuration of valence protons between the initial and
final states in the neutrinoless double- decay of Te
Xe and of Xe Ba has been
determined by measuring the cross sections of the (,He) reaction with
101-MeV deuterons. Together with our recent determination of the relevant
neutron configurations involved in the process, a quantitative comparison with
the latest shell-model and interacting-boson-model calculations reveals
significant discrepancies. These are the same calculations used to determine
the nuclear matrix elements governing the rate of neutrinoless double-
decay in these systems.Comment: 10 pages, 4 figures, 9 table
The merger of vertically offset quasi-geostrophic vortices
We examine the critical merging distance between two equal-volume, equal-potential-vorticity quasi-geostrophic vortices. We focus on how this distance depends on the vertical offset between the two vortices, each having a unit mean height-to-width aspect ratio. The vertical direction is special in the quasi-geostrophic model (used to capture the leading-order dynamical features of stably stratified and rapidly rotating geophysical flows) since vertical advection is absent. Nevertheless vortex merger may still occur by horizontal advection. In this paper, we first investigate the equilibrium states for the two vortices as a function of their vertical and horizontal separation. We examine their basic properties together with their linear stability. These findings are next compared to numerical simulations of the nonlinear evolution of two spheres of potential vorticity. Three different regimes of interaction are identified, depending on the vertical offset. For a small offset, the interaction differs little from the case when the two vortices are horizontally aligned. On the other hand, when the vertical offset is comparable to the mean vortex radius, strong interaction occurs for greater horizontal gaps than in the horizontally aligned case, and therefore at significantly greater full separation distances. This perhaps surprising result is consistent with the linear stability analysis and appears to be a consequence of the anisotropy of the quasi-geostrophic equations. Finally, for large vertical offsets, vortex merger results in the formation of a metastable tilted dumbbell vortex.Publisher PDFPeer reviewe
Quaternary Heterogeneities: geospatial products for scientists, industry and decision making
Glaciation and permafrost has had a profound impact upon the UK landscape during the Quaternary. Their impact is most relevant within the ‘zone of human interaction’, the surface and near-surface parts of the geological record that humans utilise and exploit for societal and economic gain (e.g. infrastructure development, groundwater, energy, storage and minerals). However, whilst the broad range of glacial and periglacial processes that have affected the UK are known, their spatial influence on the applied properties of the substrate are poorly-understood but have major implications for ground conditions and civil engineering. This lack of understanding is partly due to the complexity of the geological evidence, point or linear approaches to geological investigation and ‘lithostratigraphic’ approaches that have largely-overlooked the significance of heterogeneous products of glaciation and permafrost.
Within this project, we are developing a range of national-scale GIS datasets that will highlight the ‘known’ distribution of specific ‘Quaternary Heterogeneities’ in the shallow sub-surface and identify zones of extrapolated susceptibility in areas where data coverage is limited using a series of genetic and geostatistical rules. Spatial data-sets are currently in development for glaciotectonic structure, buried valleys, drift-filled hollows, blockfields and frost weathering. These datasets are aimed at both scientific and applied users (e.g. civil engineers, insurers, hydrogeologists, planners and decision makers), enhancing scientific understanding of glacial and periglacial processes and their spatial influence on the properties of the landscape and sub-surface
Health survey on the Ilha da Conceição, state of Rio de Janeiro, II: selected health characteristics in children
Assessing L2 vocabulary depth with word associates format tests: issues, findings, and suggestions
Word Associates Format (WAF) tests are often used to measure second language learners’ vocabulary depth with a focus on their network knowledge. Yet, there were often many variations in the specific forms of the tests and the ways they were used, which tended to have an impact on learners’ response behaviors and, more importantly, the psychometric properties of the tests. This paper reviews the general practices, key issues, and research findings that pertain to WAF tests in four major areas, including the design features of WAF tests, conditions for test administration, scoring methods, and test-taker characteristics. In each area, a set of variables is identified and described with relevant research findings also presented and discussed. Around eight topics, the General Discussion section provides some suggestions and directions for the development of WAF tests and the use of them as research tools in the future. This paper is hoped to help researchers become better aware that the results generated by a WAF test may vary depending on what specific design the test has, how it is administered and scored, and who the learners are, and consequently, make better decisions in their research that involves a WAF test
UK Geoenergy Observatories Glasgow: GGC01 cored, seismic monitoring borehole – intermediate data release
This report gives an overview of information related to an intermediate data release of the borehole information pack for UK Geoenergy Observatories: Glasgow borehole GGC01.
The cored, seismic monitoring borehole GGC01 (BGS SOBI number NS66SW BJ 3754, BGS ID 20650619) was drilled between 19 November and 12 December 2018 producing a core of 102 mm diameter. The borehole was wireline logged in December 2018 and a string of 5 seismometers were installed in February 2019.
The core was transported to the National Geological Repository (NGR) at BGS Keyworth and was curated into 1 m core boxes. State-of-the-art core scanners are being used to collect radiographic, CT, optical images, geophysical log and XRF along core datasets. Optical images and radiographic images are included in the intermediate release. Also included are sedimentary, discontinuity and engineering log
Understanding the influence of race/Ethnicity, gender, and class on inequalities in academic and non-academic outcomes among eighth-grade students: findings from an intersectionality approach
Socioeconomic, racial/ethnic, and gender inequalities in academic achievement have been widely reported in the US, but how these three axes of inequality intersect to determine academic and non-academic outcomes among school-aged children is not well understood. Using data from the US Early Childhood Longitudinal Study—Kindergarten (ECLS-K; N = 10,115), we apply an intersectionality approach to examine inequalities across eighth-grade outcomes at the intersection of six racial/ethnic and gender groups (Latino girls and boys, Black girls and boys, and White girls and boys) and four classes of socioeconomic advantage/disadvantage. Results of mixture models show large inequalities in socioemotional outcomes (internalizing behavior, locus of control, and self-concept) across classes of advantage/disadvantage. Within classes of advantage/disadvantage, racial/ethnic and gender inequalities are predominantly found in the most advantaged class, where Black boys and girls, and Latina girls, underperform White boys in academic assessments, but not in socioemotional outcomes. In these latter outcomes, Black boys and girls perform better than White boys. Latino boys show small differences as compared to White boys, mainly in science assessments. The contrasting outcomes between racial/ethnic and gender minorities in self-assessment and socioemotional outcomes, as compared to standardized assessments, highlight the detrimental effect that intersecting racial/ethnic and gender discrimination have in patterning academic outcomes that predict success in adult life. Interventions to eliminate achievement gaps cannot fully succeed as long as social stratification caused by gender and racial discrimination is not addressed
La ricerca in Psicologia Clinica Perinatale : fattori di rischio e protezione per la tutela della salute mentale
Female Sex Worker Social Networks and STI/HIV Prevention in South China
Reducing harm associated with selling and purchasing sex is an important public health priority in China, yet there are few examples of sustainable, successful programs to promote sexual health among female sex workers. The limited civil society and scope of nongovernmental organizations circumscribe the local capacity of female sex workers to collectively organize, advocate for their rights, and implement STI/HIV prevention programs. The purpose of this study was to examine social networks among low-income female sex workers in South China to determine their potential for sexual health promotion.Semi-structured interviews with 34 low-income female sex workers and 28 health outreach members were used to examine how social relationships affected condom use and negotiation, STI/HIV testing and health-seeking behaviors, and dealing with violent clients. These data suggested that sex worker's laoxiang (hometown social connections) were more powerful than relationships between women selling sex at the same venue in establishing the terms and risk of commercial sex. Female sex workers from the same hometown often migrated to the city with their laoxiang and these social connections fulfilled many of the functions of nongovernmental organizations, including collective mobilization, condom promotion, violence mitigation, and promotion of health-seeking behaviors. Outreach members observed that sex workers accompanied by their laoxiang were often more willing to accept STI/HIV testing and trust local sexual health services.Organizing STI/HIV prevention services around an explicitly defined laoxiang social network may provide a strong foundation for sex worker health programs. Further research on dyadic interpersonal relationships between female sex workers, group dynamics and norm establishment, and the social network characteristics are needed
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