Exact solution, scaling behaviour and quantum dynamics of a model of an atom-molecule Bose-Einstein condensate

We study the exact solution for a two-mode model describing coherent coupling between atomic and molecular Bose-Einstein condensates (BEC), in the context of the Bethe ansatz. By combining an asymptotic and numerical analysis, we identify the scaling behaviour of the model and determine the zero temperature expectation value for the coherence and average atomic occupation. The threshold coupling for production of the molecular BEC is identified as the point at which the energy gap is minimum. Our numerical results indicate a parity effect for the energy gap between ground and first excited state depending on whether the total atomic number is odd or even. The numerical calculations for the quantum dynamics reveals a smooth transition from the atomic to the molecular BEC.Comment: 5 pages, 4 figure

Controlling magnetic order and quantum disorder in molecule-based magnets

We investigate the structural and magnetic properties of two molecule-based magnets synthesized from the same starting components. Their different structural motifs promote contrasting exchange pathways and consequently lead to markedly different magnetic ground states. Through examination of their structural and magnetic properties we show that [Cu(pyz)(H2O)(gly)2](ClO4)2 may be considered a quasi-one-dimensional quantum Heisenberg antiferromagnet whereas the related compound [Cu(pyz)(gly)](ClO4), which is formed from dimers of antiferromagnetically interacting Cu2+ spins, remains disordered down to at least 0.03 K in zero field but shows a field-temperature phase diagram reminiscent of that seen in materials showing a Bose-Einstein condensation of magnons

Measuring stress in medical education: validation of the Korean version of the higher education stress inventory with medical students

Background: Medical students face a variety of stressors associated with their education; if not promptly identified and adequately dealt with, it may bring about several negative consequences in terms of mental health and academic performance. This study examined psychometric properties of the Korean version of the Higher Education Stress Inventory (K-HESI). Methods: The reliability and validity of the K-HESI were examined in a large scale multi-site survey involving 7110 medical students. The K-HESI, Beck Depression Inventory (BDI) and questions regarding quality of life (QOL) and self-rated physical health (SPH) were administered. Results: Exploratory factor analysis of the K-HESI identified seven factors: Low commitment; financial concerns; teacher-student relationship; worries about future profession; non-supportive climate; workload; and dissatisfaction with education. A subsequent confirmatory factor analysis supported the 7-factor model. Internal consistency of the K-HESI was satisfactory (Cronbach's a = .78). Convergent validity was demonstrated by its positive association with the BDI. Known group validity was supported by the K-HESI's ability to detect significant differences on the overall and subscale scores of K-HESI according to different levels of QOL and SPH. Conclusions: The K-HESI is a psychometrically valid tool that comprehensively assesses various relevant stressors related to medical education. Evidence-based stress management in medical education empirically guided by the regular assessment of stress using reliable and valid measure is warranted.open

Successful recruitment to trials : findings from the SCIMITAR+ Trial

BACKGROUND: Randomised controlled trials (RCT) can struggle to recruit to target on time. This is especially the case with hard to reach populations such as those with severe mental ill health. The SCIMITAR+ trial, a trial of a bespoke smoking cessation intervention for people with severe mental ill health achieved their recruitment ahead of time and target. This article reports strategies that helped us to achieve this with the aim of aiding others recruiting from similar populations. METHODS: SCIMITAR+ is a multi-centre pragmatic two-arm parallel-group RCT, which aimed to recruit 400 participants with severe mental ill health who smoke and would like to cut down or quit. The study recruited primarily in secondary care through community mental health teams and psychiatrists with a smaller number of participants recruited through primary care. Recruitment opened in October 2015 and closed in December 2016, by which point 526 participants had been recruited. We gathered information from recruiting sites on strategies which led to the successful recruitment in SCIMITAR+ and in this article present our approach to trial management along with the strategies employed by the recruiting sites. RESULTS: Alongside having a dedicated trial manager and trial management team, we identified three main themes that led to successful recruitment. These were: clinicians with a positive attitude to research; researchers and clinicians working together; and the use of NHS targets. The overriding theme was the importance of relationships between both the researchers and the recruiting clinicians and the recruiting clinicians and the participants. CONCLUSIONS: This study makes a significant contribution to the limited evidence base of real-world cases of successful recruitment to RCTs and offers practical guidance to those planning and conducting trials. Building positive relationships between clinicians, researchers and participants is crucial to successful recruitment

In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs

Comment in Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016] In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016] US oncologists call for government regulation to curb drug price rises. [BMJ. 2015

Vitamin D status in mothers with pre-eclampsia and their infants: a case-control study from Serbia, a country without a vitamin D fortification policy

Objective: The objective of the present study was to determine if vitamin D intake and status are associated with pre-eclampsia in a country without a vitamin D fortification policy. Design: A case-control study of pregnancies with (case) and without (control) pre-eclampsia was conducted from January to April when UVB is minimal. Maternal and cord blood obtained at delivery were measured for plasma 25-hydroxycholecalciferol (25-OH-D-3), 3-epimer of 25-OH-D-3 (3-epi-25-OH-D-3) and 24,25-dihydroxycholecalciferol (24,25-(OH)(2)D-3) by LC-MS/MS and maternal 1,25-dihydroxyvitamin D (1,25-(OH) 2D). Differences between groups were tested with ANOVA and Bonferroni post hoc tests (P lt 0.05). Setting: Clinical Center of Serbia. Subjects: Pregnant women with and without pre-eclampsia (n 60) and their infants. Results: Exogenous vitamin D intake (0.95-16.25 mu g/d (38-650 IU/d)) was not significantly different between groups. Women with pre-eclampsia delivered infants at an earlier gestational age and had significantly lower mean total plasma 25-hydroxyvitamin D (25-OH-D; case: 11.2 (SD 5.1); control: 16.1 (SD 5.7) ng/ml; P=0.0006), 25-OH-D-3 (case: 10.0 (SD 4.9); control: 14.2 (SD 5.8) ng/ml; P=0.002), 3-epi-25-OH-D-3 (case: 0.5 (SD 0.2); control: 0.7 (SD 0.2) ng/ml; P=0.0007) and 1,25-(OH)(2)D (case: 56.5 (SD 26.6); control: 81.0 (SD 25.7) pg/ml; P=0.018), while 24,25-(OH)(2)D-3 was not different between groups. Infants did not differ in total plasma 25-OH-D, 25-OH-D-3, 3-epi-25-OH-D-3 and 24,25-(OH)(2)D-3, but the mean proportion of 3-epi-25-OH-D-3 was higher in the infant case group (case: 7.9 (SD 1.1); control: 7.0 (SD 1.4) % of total 25-OH-D-3; P=0.005). Conclusions: A high prevalence of vitamin D deficiency, as defined by plasma 25-OH-D lt 12 ng/ml, was observed in 47 % of all mothers and 77 % of all infants. These data underscore the need for prenatal vitamin D supplementation and a food fortification policy in Serbia

Psychosocial and sexual factors associated with recent sexual health clinic attendance and HIV testing among trans people in the UK.

OBJECTIVES: Trans people remain an understudied population in the UK, with unmet sexual health needs. The aim of this research was to identify possible barriers and facilitators for sexual health clinic attendance and HIV testing among trans people. METHODS: Lesbian, gay, bisexual and transgender (LGBT) participants from across the UK were invited to take part in a cross-sectional online survey through Facebook advertising (April-June 2018). Psychosocial and sexual factors associated with recent sexual health clinic attendance, and ever having an HIV test were examined using multivariate logistic regression. RESULTS: A total of 3007 cisgender and 500 trans participants completed the survey. Trans participants were less likely to attend a sexual health clinic than cisgender participants (27% vs 36%, p<0.001) and report ever having an HIV test (49% vs 64%, p<0.001). One trans participant reported living with HIV and three reported currently taking pre-exposure prophylaxis. Factors associated with trans sexual health clinic attendance were: living in London, having a relationship with multiple partners, engaging in condomless anal intercourse, greater life satisfaction, and having alcohol and/or drugs before sex. Being a person of colour, aged 25-49 years, in a relationship with multiple partners, condomless anal intercourse, lower body dissatisfaction, and having drugs before sex were associated with ever having an HIV test among trans participants. CONCLUSIONS: Trans people were less likely to attend sexual health services than cisgender people, and half of trans participants who reported condomless anal intercourse had never had an HIV test. Further research is needed to understand and improve uptake of sexual health services among trans people

Validity of an FFQ assessing the vitamin D intake of young Serbian women living in a region without food fortification: the method of triads model

Objective: The objective of the present study was to examine the external validity of an FFQ designed to estimate dietary vitamin D intake compared with a plasma biomarker and three repeated 24 h dietary recalls in women of reproductive age in Serbia, where there is no exposure to food fortified with vitamin D. The method of triads was applied. Design: In a cross-sectional study, 422 women completed the Women and Reproductive Health FFQ (WRH-FFQ) during the winter months. From a representative subgroup (n 44), three 24 h dietary recalls and anthropometric parameters were collected as well as a fasting blood sample for vitamin D biomarker analyses. Correlation coefficients were calculated between each of the dietary methods. Validity coefficients, as a correlation between the measured and estimated 'true' exposure, were calculated using the method of triads. Bland-Altman plots were also constructed. Setting: Three major universities in Serbia. Subjects: Healthy young women (n 422) aged 18-35 years. Results: The WRH-FFQ estimate of vitamin D intake for all participants was 4.0 (SD 3.3) mu g/d and 3.1 (SD 2.3) mu g/d for the subgroup. Bland-Altman plots for these intakes showed high agreement. Validity coefficients for the FFQ, 24 h recall and biomarker were. rho(QI) = 0.847 (95 % CI 0.564, 0.928), rho(RI) = 0.810 (95 % CI 0.537, 0.997) and rho(BI) = 0.499 (95 % CI 0.190, 0.840), while the correlation coefficients were 0.686, 0.422 and 0.404. Conclusions: The FFQ applied in the present study is a valid tool for assessing dietary vitamin D intake in women living in Serbia, a region without mandatory vitamin D food fortification

Labor Productivity - The Use of Staffing Guides and Other Productivity Methods in U.S. Hotels: A Survey Study

This paper examines the issue of labor productivity in hotels. It elaborates on various measurement methods used by American hoteliers including staffing guides, with a special focus on productivity standards. Advantages of physical, financial and mixed methods such as percentage methods, revenue per employee, value-added, Data Envelope Analysis and Stochastic Frontier Analysis are discussed. While the use of percentages and staffing guides were found to be commonplace, results revealed that some fairly stable standards were already in place in the surveyed hotels. Results also revealed that at least in the surveyed companies, few hoteliers attempted to monitor or improve revenue per employee, focusing instead on physical labor inputs and outputs or simple labor percentages