4,974 research outputs found
E.P.R. lineshapes in maser materials
Using a 35 Gc/sec spectrometer, E.P.R. linewidths have been measured in a number of synthetic ruby specimens grown by various means. In addition, measurements of both linewidth and relaxation time have been made on a number of specimens of calcium tungstate doped with neodymiura. Using a mathematical treatment of the second moment, the homogeneously broadened ruby line has been resolved into concentration-dependent and concentration-independent components. The observed constant nature of the former suggests that the effective concentration of paramagnetic centres is not indicative of the true chemical concentration. Analysis of the inhomogeneous ruby line results in broadening components representative of axial misorientation and strain, A moderate correlation is obtained between misorientation figures derived from x-ray and e.p.r. measurements, and a similar correlation exists between strain and spin-lattice relaxation times. There appear to be no significant differences between the various types of flame-fusion material available. Preliminary analysis suggests that the homogeneous line in calcium tungstate owes its width to processes similar to those occuring in ruby, but strain does not appear to be predominant in the inhomogeneous broadening. Relaxation times in this material exhibit concentration and orientation dependence and a temperature dependence has been fitted empirically in the Direct and Raman regions
Bodyspace at the pub: sexual orientations and organizational space
In this article we argue that sexuality is not only an undercurrent of service environments, but is integral to the way that these workspaces are experienced and negotiated. Through drawing on Sara Ahmedâs (2006a) âorientationâ thesis, we develop a concept of âbodyspaceâ to suggest that individuals understand, shape and make meaning of work spaces through complex sexually-orientated negotiations. Presenting analysis from a study of UK pubs, we explore bodyspace in the lived experience of workplace sexuality through three elements of orientation: background; bodily dwelling; and lines of directionality. Our findings show how organizational spaces afford or mitigate possibilities for particular bodies, which simultaneously shape expectations and experiences of sexuality at work. Bodyspace therefore provides one way of exposing the connection between sexual âorientationâ and the lived experience of service sector work
Descriptions of Disordered Eating in German Psychiatric Textbooks, 1803â2017
The most common eating disorders (EDs) according to DSM-5 are anorexia nervosa
(AN), bulimia nervosa (BN) and binge eating disorder (BED). These disorders have
received increasing attention in psychiatry due to rising prevalence and high morbidity
and mortality. The diagnostic category âanorexia nervosa,â introduced by Ernest-Charles
LasĂšgue and William Gull in 1873, first appears a century later in a German textbook of
psychiatry, authored by Gerd Huber in 1974. However, disordered eating behavior has
been described and discussed in German psychiatric textbooks throughout the past 200
years. We reviewed content regarding eating disorder diagnoses but also descriptions
of disordered eating behavior in general. As material, we carefully selected eighteen
German-language textbooks of psychiatry across the period 1803â2017. Previously, in
German psychiatry, disordered eating behaviors were seen as symptoms of depressive
disorders, bipolar disorder or schizophrenia, or as manifestations of historical diagnoses
no longer used by the majority of psychiatrists such as neurasthenia, hypochondria and
hysteria. Interestingly, 19th and early 20th century psychiatrists like Kraepelin, Bumke,
Hoff, Bleuler, and Jaspers reported symptom clusters such as food refusal and vomiting
under these outdated diagnostic categories, whereas nowadays they are listed as core
criteria for specific eating disorder subtypes. A wide range of medical conditions such as
endocrinopathies, intestinal or brain lesions were also cited as causes of abnormal food
intake and body weight. An additional consideration in the delayed adoption of eating
disorder diagnoses in German psychiatry is that people with EDs are commonly treated
in the specialty discipline of psychosomatic medicine, introduced in Germany afterWorld
War II, rather than in psychiatry. Viewed from todayâs perspective, the classification of
disorders associated with disordered eating is continuously evolving. Major depressive
disorder, schizophrenia and physical diseases have been enduringly associated with
abnormal eating behavior and are listed as important differential diagnoses of EDs
in DSM-5. Moreover, there are overlaps regarding the neurobiological basis and
psychological and psychopharmacological therapies applied to all of these disorders
Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation
Atmospheric aerosols exert an important influence on climate through their effects on stratiform cloud albedo and lifetime and the invigoration of convective storms. Model calculations suggest that almost half of the global cloud condensation nuclei in the atmospheric boundary layer may originate from the nucleation of aerosols from trace condensable vapours, although the sensitivity of the number of cloud condensation nuclei to changes of nucleation rate may be small. Despite extensive research, fundamental questions remain about the nucleation rate of sulphuric acid particles and the mechanisms responsible, including the roles of galactic cosmic rays and other chemical species such as ammonia. Here we present the first results from the CLOUD experiment at CERN. We find that atmospherically relevant ammonia mixing ratios of 100 parts per trillion by volume, or less, increase the nucleation rate of sulphuric acid particles more than 100â1,000-fold. Time-resolved molecular measurements reveal that nucleation proceeds by a base-stabilization mechanism involving the stepwise accretion of ammonia molecules. Ions increase the nucleation rate by an additional factor of between two and more than ten at ground-level galactic-cosmic-ray intensities, provided that the nucleation rate lies below the limiting ion-pair production rate. We find that ion-induced binary nucleation of H_(2)SO_(4)âH_(2)O can occur in the mid-troposphere but is negligible in the boundary layer. However, even with the large enhancements in rate due to ammonia and ions, atmospheric concentrations of ammonia and sulphuric acid are insufficient to account for observed boundary-layer nucleation
Pharmacological assessment of ibuprofen arginate on platelet aggregation and colon cancer cell killing
This work was funded in part by grants from the Wellcome Trust (0852551Z108/Z, to J.A.M.) and British Heart Foundation (FS/16/1/31699, to NSK). SM is a recipient of a PhD award from the King of Saud University, AT is a recipient of a MRC PhD studentship
Measurement of the Fermi Constant by FAST
An initial measurement of the lifetime of the positive muon to a precision of
16 parts per million (ppm) has been performed with the FAST detector at the
Paul Scherrer Institute. The result is tau_mu = 2.197083 (32) (15) microsec,
where the first error is statistical and the second is systematic. The muon
lifetime determines the Fermi constant, G_F = 1.166353 (9) x 10^-5 GeV^-2 (8
ppm).Comment: 15 pages, 6 figure
Using e-mail recruitment and an online questionnaire to establish effect size: A worked example
Background\ud
Sample size calculations require effect size estimations. Sometimes, effect size estimations and standard deviation may not be readily available, particularly if efficacy is unknown because the intervention is new or developing, or the trial targets a new population. In such cases, one way to estimate the effect size is to gather expert opinion. This paper reports the use of a simple strategy to gather expert opinion to estimate a suitable effect size to use in a sample size calculation.\ud
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Methods\ud
Researchers involved in the design and analysis of clinical trials were identified at the University of Birmingham and via the MRC Hubs for Trials Methodology Research. An email invited them to participate.\ud
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An online questionnaire was developed using the free online tool 'Survey Monkey©'. The questionnaire described an intervention, an electronic participant information sheet (e-PIS), which may increase recruitment rates to a trial. Respondents were asked how much they would need to see recruitment rates increased by, based on 90%. 70%, 50% and 30% baseline rates, (in a hypothetical study) before they would consider using an e-PIS in their research.\ud
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Analyses comprised simple descriptive statistics.\ud
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Results\ud
The invitation to participate was sent to 122 people; 7 responded to say they were not involved in trial design and could not complete the questionnaire, 64 attempted it, 26 failed to complete it. Thirty-eight people completed the questionnaire and were included in the analysis (response rate 33%; 38/115). Of those who completed the questionnaire 44.7% (17/38) were at the academic grade of research fellow 26.3% (10/38) senior research fellow, and 28.9% (11/38) professor. Dependent upon the baseline recruitment rates presented in the questionnaire, participants wanted recruitment rate to increase from 6.9% to 28.9% before they would consider using the intervention.\ud
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Conclusions\ud
This paper has shown that in situations where effect size estimations cannot be collected from previous research, opinions from researchers and trialists can be quickly and easily collected by conducting a simple study using email recruitment and an online questionnaire. The results collected from the survey were successfully used in sample size calculations for a PhD research study protocol.\ud
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Comparison of optical model results from a microscopic Schr\"odinger approach to nucleon-nucleus elastic scattering with those from a global Dirac phenomenology
Comparisons are made between results of calculations for intermediate energy
nucleon-nucleus scattering for 12C, 16O, 40Ca, 90Zr, and 208Pb, using optical
potentials obtained from global Dirac phenomenology and from a microscopic
Schr\"odinger model. Differential cross sections and spin observables for
scattering from the set of five nuclei at 65 MeV and 200 MeV have been studied
to assess the relative merits of each approach. Total reaction cross sections
from proton-nucleus and total cross sections from neutron-nucleus scattering
have been evaluated and compared with data for those five targets in the energy
range 20 MeV to 800 MeV. The methods of analyses give results that compare well
with experimental data in those energy regimes for which the procedures are
suited.Comment: 22 pages, 12 figure
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