3,638 research outputs found
Atom-molecule conversion with particle losses
Based on the mean-field approximation and the phase space analysis, we study
the dynamics of an atom-molecule conversion system subject to particle loss.
Starting from the many-body dynamics described by a master equation, an
effective nonlinear Schr\"odinger equation is introduced. The classical phase
space is then specified and classified by fixed points. The boundary, which
separate different dynamical regimes have been calculated and discussed. The
effect of particle loss on the conversion efficiency and the self-trapping is
explored.Comment: 6 pages, 5 figure
A Complete Sample of Megaparsec Size Double Radio Sources from SUMSS
We present a complete sample of megaparsec-size double radio sources compiled
from the Sydney University Molonglo Sky Survey (SUMSS). Almost complete
redshift information has been obtained for the sample. The sample has the
following defining criteria: Galactic latitude |b| > 12.5 deg, declination <
-50 deg and angular size > 5 arcmin. All the sources have projected linear size
larger than 0.7 Mpc (assuming H_o = 71 km/s/Mpc). The sample is chosen from a
region of the sky covering 2100 square degrees. In this paper, we present
843-MHz radio images of the extended radio morphologies made using the Molonglo
Observatory Synthesis Telescope (MOST), higher resolution radio observations of
any compact radio structures using the Australia Telescope Compact Array
(ATCA), and low resolution optical spectra of the host galaxies from the 2.3-m
Australian National University (ANU) telescope at Siding Spring Observatory.
The sample presented here is the first in the southern hemisphere and
significantly enhances the database of known giant radio sources. The giant
radio sources with linear size exceeding 0.7 Mpc have an abundance of (215
Mpc)^(-3) at the sensitivity of the survey. In the low redshift universe, the
survey may be suggesting the possibility that giant radio sources with relict
lobes are more numerous than giant sources in which beams from the centre
currently energize the lobes.Comment: 67 pages, 29 figures, for full resolution figures see
http://www.astrop.physics.usyd.edu.au/SUMSS/PAPERS/Submit-May11-ms.pd
A new species of stalked crinoid (Echinodermata) of possible Late Silurian age from central Newfoundland
A new fossil locality within a sequence previously assigned to the Middle Ordovician Baie D'Espoir Group in south-central Newfoundland contains fragmented crinoid columnals and brachiopods. Distinctive, pentastellate crinoid columnals, similar to those assigned to the monobathrid camerate Hexacrinites Austin and Austin by Russian authors, are named Hexacrinites? Pentastellatus n. sp. Nodal(?) columnals of this species have a circular, depressed articular facet, with a conical to bowl-like crenularium, a depressed, circular areola, a raised perilumen and a short, slender axial canal of pentagonal section. The oldest Hexacrinites sensu stricto are Late Silurian, suggesting that the fossiliferous strata have been incorrectly assigned to the Ordovician. Cross-sections of brachiopods from the same locality include an example that resembles several Early Silurian to Late Devonian pentameroid genera including Brooksina Kirk, 1922. Correlation with Late Silurian, bivalve-bearing strata SO km to the northeast would indicate that a major unconformity may occur above the fossiliferous Early and Middle Ordovician strata and the Early Ordovician ophiolite complexes.
RÉSUMÉ
Un nouvel emplacement de fossiles à I'intérieur d'une sequence auparavant attribute au groupe de l'Ordovicien moyen de Baie d'Espoir dans le centre-sud de Terre-Neuve renferme des fragments de columnales et de brachiopodes de crinoldes. Des columnales de crinoldes pentaétoilées caractéristiqucs, semblables à celles attributées à l’Hexacrinites Austin and Austin à loges monobathrides par des auteurs russes, sont baptisées nouvelle espèce pentastellatus d'Hexacrinites?. Les columnales nodales(?) de cette espèce sont pourvues d'une facette articulaire renfoncée et circulaire munie d'un crenularium allant de conique à bombé, d'une aréole circulaire renfoncie, d'un périlumen surélevé et d'un canal axial mince et court de section pentagonalc. Les plus anciens Hexacrinites, au sens strict, remontent au Silurien supérieur, ce qui permet de supposer qu'on a incorrectement attribué la strate fossilifère à l'Ordovicien. Des iéchantillons représentatifs de brachiopodes du même emplacement comprennent un exemple qui ressemble à plusieurs genres de pentaméroides datant du Silurien inférieur au Dévonien supérieur, notamment le Brooksina Kirk, 1922. Leur corrélation avec des strates renfermant des bivalves du Silurien supérieur à 50 km au nord-cst signale qu'une discordance importantc pourrait se présenter au-dessus des strates fossiliferes de l'Ordovicien inférieur ou moyen de même que des complexes d'ophiolites de l'Ordovicien inférieur.
[Traduit par la rédaction
A speed-of-play limit reduces gambling expenditure in an online roulette game: Results of an online experiment
UK online casino games are presently not subject to any limitations on speed-of-play or stakes. One recent policy proposal is to ensure that no online casino game can be played faster than its in-person equivalent. Another policy proposal is to limit the maximum stakes on online casino games to £2, to match the current stake limit on electronic gambling machines. This research experimentally investigated the speed-of-play proposal subject to a £2 stake limit, in an online experiment using incentivized payouts based on £4 endowments and a commercial online roulette game, which was slowed-down in one condition to enforce a speed-of-play limit of one spin every 60 seconds. UK residents, aged 18 years and over and with experience in playing online roulette (N = 1,002), were recruited from an online crowdsourcing panel. In the slowed-down condition there was a credible reduction in the amount gambled. This effect occurred via a credible reduction in the mean number of spins which outweighed any potential increases in bet sizes. Speed-of-play limits may be effective in reducing gambling expenditure for online roulette
Racial Comparisons in Police Officer Bench Press Strength over 12.5 Years
International Journal of Exercise Science 7(2) : 140-151, 2014. Strength, when considering gender and race, provides a basis for training, hiring, and retention for police officers. The purpose of this study is to identify muscular strength differences among racial groups from initial-recruit to in-service tests. Strength variables included bench press, bench press/lean mass and bench press/body mass. Scores were retrieved for the 1990 to 1995 recruit classes and were paired to the 2006 in-service fitness log. Sample included 309 officers: 30 females (13 black, 17 white) and 279 males (41 black, 238 white). Mean age of recruit was 24.6 ± 3.4 years and for in-service was 37.1 ± 3.7 years. Time between tests was 12.5 ± 2.0 years. Bench press strength significantly increased for all gender and racial groups. Black males were significantly stronger in bench press at initial-recruit and at in-service than white males. All racial and gender groups increased in bench press/lean mass, however, the increase in white females was not significant. No differences were found between black and white females in all strength variables at both testing periods. Black males were significantly stronger than white males in bench press/body mass only at the initial-recruit test. White males showed a significant increase in bench press/body mass over time, but they did not reach the strength level of the black males at in-service. Police departments, with a properly designed physical fitness program, can expect to see increases in strength of personnel over the first half of their careers; however, there are gender and racial differences
Bilateral symmetry breaking in a nonlinear Fabry-Perot cavity exhibiting optical tristability
We show the existence of a region in the parameter space that defines the
field dynamics in a Fabry-Perot cylindrical cavity, where three output stable
stationary states of the light are possible for a given localized incident
field. Two of these states do not preserve the bilateral (i.e. left-right)
symmetry of the entire system. These broken-symmetry states are the
high-transmission nonlinear modes of the system. We also discuss how to excite
these states.Comment: 5 pages, 5 figure
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The biological embedding of early-life socioeconomic status and family adversity in children's genome-wide DNA methylation.
AimTo examine variation in child DNA methylation to assess its potential as a pathway for effects of childhood social adversity on health across the life course.Materials & methodsIn a diverse, prospective community sample of 178 kindergarten children, associations between three types of social experience and DNA methylation within buccal epithelial cells later in childhood were examined.ResultsFamily income, parental education and family psychosocial adversity each associated with increased or decreased DNA methylation (488, 354 and 102 sites, respectively) within a unique set of genomic CpG sites. Gene ontology analyses pointed to genes serving immune and developmental regulation functions.ConclusionFindings provided support for DNA methylation as a biomarker linking early-life social experiences with later life health in humans
Adolescent chronic illness : a qualitative study of psychosocial adjustment
Introduction: The purpose of this study was to investigate the psychosocial issues facing young people living with a chronic medical condition. Materials and Methods: Subjects were young people with a range of medical conditions who were on a waiting list to participate in the Chronic Illness Peer Support programme at the Centre for Adolescent Health, Royal Children\u27s Hospital, Melbourne, Australia. Young people agreed to in-depth interviews which were taped and transcribed. Thematic analysis was undertaken by two researchers working independently. Results: Thirty-five young people were interviewed. Thematic analysis revealed five broad themes: control (in control, under control, out of control); emotional reactions (happiness, frustration, anger, sadness, anxiety); acceptance (of illness, of others, of self); coping strategies, and; a search for meaning. The importance of social connections was emphasised. While illustrating the difficulties of managing a chronic medical condition during adolescence, a generally positive message emerges about these young people. Conclusions: Many young people with chronic illness appear relatively resilient in the face of the adjustment challenges presented by their illness. Interventions that allow a young person to explore meaning, build self-esteem, and acceptance through positive social connections are likely to improve adjustment outcomes in this group.<br /
Sulfur speciation in lunar apatite
Apatite incorporates several volatile elements (including S, as SO_4 ^(2-)) and can provide a record of magmatic volatile
evolution. Recent measurements of volatiles in apatite from Apollo sample 14053.241 revealed 300-450 ppm S. Although
many lunar melts have sufficient S for sulfide saturation, the observed S content of lunar apatite is surprising because lunar
samples (especially 14053) are highly reduced (≤ IW) and are thus expected to contain little SO_4 ^(2-). One possibility is that
there are micro-environments in late-stage lunar melts that are more oxidized than one would infer from conditions recorded
by other components of these rocks. Alternatively, it may be that S^(2-) substitutes for F+Cl+OH in lunar apatite: S^(2—)bearing
apatite has been synthesized, but to our knowledge has not been observed in nature
Pharmacists’ opinions of the value of CAPE Outcomes in hiring decisions
Objective. The Hiring Intent Reasoning Examination (HIRE) was designed to explore the utility of the CAPE 2013 outcomes attributes from the perspective of practicing pharmacists, examine how each attribute influences hiring decisions, and identify which of the attributes are perceived as most and least valuable by practicing pharmacists. Methods. An electronic questionnaire was developed and distributed to licensed pharmacists in four states to collect their opinions about 15 CAPE subdomains plus five additional business related attributes. The attributes that respondents identified were: necessary to be a good pharmacist, would impact hiring decisions, most important to them, and in short supply in the applicant pool. Data were analyzed using statistical analysis software to determine the relative importance of each to practicing pharmacists and various subsets of pharmacists. Results. The CAPE subdomains were considered necessary for most jobs by 51% or more of the 3723 respondents (range, 51% to 99%). The necessity for business-related attributes ranged from 21% to 92%. The percentage who would not hire an applicant who did not possess the attribute ranged from 2% to 71.5%; the percentage who considered the attribute most valuable ranged from 0.3% to 35%; and the percentage who felt the attribute was in short supply ranged from 5% to 36%. Opinions varied depending upon gender, practice setting and whether the pharmacist was an employee or employer. Conclusion. The results of this study can be used by faculty and administrators to inform curricular design and emphasis on CAPE domains and business-related education in pharmacy programs
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