Postscript: Queer Endings/Queer Beginnings

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Variational collocation for systems of coupled anharmonic oscillators

We have applied a collocation approach to obtain the numerical solution to the stationary Schr\"odinger equation for systems of coupled oscillators. The dependence of the discretized Hamiltonian on scale and angle parameters is exploited to obtain optimal convergence to the exact results. A careful comparison with results taken from the literature is performed, showing the advantages of the present approach.Comment: 14 pages, 10 table

An application of the finite-discrete element method in the simulation of ceramic breakage: methodology for a validation study for alumina specimens

Alumina (aluminum oxide, Al2O3) particles are pelletised and fired to produce high porosity catalyst pellets of complex shapes. These pellets fill cylindrical reactor columns with particulate packing structures that are key to the in-service performance, but will suffer breakages which impact on catalyst performance. The combined Finite- Discrete Element Method (FEMDEM) is ideally suited to the simulation of both the multi-body pellet dynamic packing and quasi-static interactions as well as the stress field of each individual pellet, its deformations and fragmentation. The application of FEMDEM fracture modelling to a fine-grained brittle and porous material is novel. This paper presents a methodology for a validation study through comparison with three point- bending and Brazilian tests and discusses FEMDEMs potential in modelling multi-body fragile systems

Accuracy of the Semi--Classical Approximation: the Pullen Edmonds Hamiltonian

A test on the numerical accuracy of the semiclassical approximation as a function of the principal quantum number has been performed for the Pullen--Edmonds model, a two--dimensional, non--integrable, scaling invariant perturbation of the resonant harmonic oscillator. A perturbative interpretation is obtained of the recently observed phenomenon of the accuracy decrease on the approximation of individual energy levels at the increase of the principal quantum number. Moreover, the accuracy provided by the semiclassical approximation formula is on the average the same as that provided by quantum perturbation theory.Comment: 12 pages, 5 figures (available upon request to the authors), LaTex, DFPD/93/TH/47, to be published in Nuovo Cimento

Changes in the expression of the type 2 diabetes-associated gene VPS13C in the β cell are associated with glucose intolerance in humans and mice

Single nucleotide polymorphisms (SNPs) close to the VPS13C, C2CD4A and C2CD4B genes on chromosome 15q are associated with impaired fasting glucose and increased risk of type 2 diabetes. eQTL analysis revealed an association between possession of risk (C) alleles at a previously implicated causal SNP, rs7163757, and lowered VPS13C and C2CD4A levels in islets from female (n = 40, P < 0.041) but not from male subjects. Explored using promoter-reporter assays in β-cells and other cell lines, the risk variant at rs7163757 lowered enhancer activity. Mice deleted for Vps13c selectively in the β-cell were generated by crossing animals bearing a floxed allele at exon 1 to mice expressing Cre recombinase under Ins1 promoter control (Ins1Cre). Whereas Vps13cfl/fl:Ins1Cre (βVps13cKO) mice displayed normal weight gain compared with control littermates, deletion of Vps13c had little effect on glucose tolerance. Pancreatic histology revealed no significant change in β-cell mass in KO mice vs. controls, and glucose-stimulated insulin secretion from isolated islets was not altered in vitro between control and βVps13cKO mice. However, a tendency was observed in female null mice for lower insulin levels and β-cell function (HOMA-B) in vivo. Furthermore, glucose-stimulated increases in intracellular free Ca2+ were significantly increased in islets from female KO mice, suggesting impaired Ca2+ sensitivity of the secretory machinery. The present data thus provide evidence for a limited role for changes in VPS13C expression in conferring altered disease risk at this locus, particularly in females, and suggest that C2CD4A may also be involved

An application of the finite-discrete element method in the simulation of ceramic breakage: methodology for a validation study for alumina specimens

Alumina (aluminum oxide, Al2O3) particles are pelletised and fired to produce high porosity catalyst pellets of complex shapes. These pellets fill cylindrical reactor columns with particulate packing structures that are key to the in-service performance, but will suffer breakages which impact on catalyst performance. The combined FiniteDiscrete Element Method (FEMDEM) is ideally suited to the simulation of both the multi-body pellet dynamic packing and quasi-static interactions as well as the stress field of each individual pellet, its deformations and fragmentation. The application of FEMDEM fracture modelling to a fine-grained brittle and porous material is novel. This paper presents a methodology for a validation study through comparison with three pointbending and Brazilian tests and discusses FEMDEM's potential in modelling multi-body fragile systems

Searching for Faint Comoving Companions to the α Centauri system in the VVV Survey Infrared Images

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2017 Crown Copyright. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.The VVV survey has observed the southern disk of the Milky Way in the near infrared, covering 240 deg$^{2}$ in the $ZYJHK_S$ filters. We search the VVV Survey images in a $\sim$19 deg$^{2}$ field around $\alpha$ Centauri, the nearest stellar system to the Sun, to look for possible overlooked companions that the baseline in time of VVV would be able to uncover. The photometric depth of our search reaches $Y\sim$19.3 mag, $J\sim$19 mag, and $K_S\sim$17 mag. This search has yielded no new companions in $\alpha$ Centauri system, setting an upper mass limit for any unseen companion well into the brown dwarf/planetary mass regime. The apparent magnitude limits were turned into effective temperature limits, and the presence of companion objects with effective temperatures warmer than 325K can be ruled out using different state-of-the-art atmospheric models. These limits were transformed into mass limits using evolutionary models, companions with masses above 11 M$_{Jup}$ were discarded, extending the constraints recently provided in the literature up to projected distances of dPeer reviewedFinal Published versio

Experimental ionization of atomic hydrogen with few-cycle pulses

We present the first experimental data on strong-field ionization of atomic hydrogen by few-cycle laser pulses. We obtain quantitative agreement at the 10% level between the data and an {\it ab initio} simulation over a wide range of laser intensities and electron energies

Feasibility of mHealth technology use among a sample of isolated rural men at high risk for cardiovascular disease

Purpose/Hypothesis: Isolated rural men are considered a health disparities group at high risk for cardiovascular disease. The increasing availability of technologies for self-monitoring for healthy eating, activity and weight loss (ie mHealth) may show promise for engaging rural men in lifestyle modification. This study investigated the feasibility of men from rural isolated areas to use a fitness monitor with text messaging support over a 3- week period. The study examined the men’s daily monitor use for tracking activity and eating, and assessed via written survey, their perspectives about mHealth. Number of Subjects: Twelve men, ages 40 to 69, from a US Department of Agriculture defined isolated rural area, participated. These men were a purposive sample originally recruited to participate in a focus group about their perceptions of the utility of mHealth. The men (50.9 6 8.6 yrs) had a baseline BMI of 25 to 44 kg/m2 (34.8 6 6.6 kg/m2). Eligibility included having cell/smartphones capable of sending/ receiving text messages, access to a computer, willing to use a fitness monitor and have research personnel access the men’s logs. Materials/Methods: Men participated in 2 visits at a community center located within 70 miles of their residence, at baseline and 3 weeks. Assessments included baseline health histories and vital sign biomarkers. The men received training using the fitness monitor with supporting technologies (cell/ smartphone and computer) and were asked to wear the monitor daily for 3 weeks. Men received 1–3 text messages/day for 3 weeks for reminders, education and motivation for self-monitoring. At visit 2, men completed post-intervention surveys about their fitness monitoring. Descriptive data were used for analysis. Results: Men were overweight (n 5 3) or obese (n 5 9) and most (9/12) were hypertensive with only four being treated with medications. One man was hypertensive stage 2 under no treatment and another was pre-hypertensive. Nine of 12 men wore the monitor during all 21 days, two wore it 9 and 15 days respectively and one lost the monitor. Survey data of the 12 men revealed seven checking their step count more than 5 times/day, 6 reported using the associated smart phone app and seven used the optional sleep log feature. Eleven of 12 men manually entered food into the log and most (9/12) did this on $15 days. Ten men indicated the log was helpful in learning about eating; though only 3 indicated it was easy to log food. All men reported reading reminder and motivational text messages sent during the study and 11 plan to continue using the fitness monitor. Conclusions: Men were not well managed for blood pressure or overweight/obesity. Both the log records and the survey results indicated that using fitness monitors was feasible and acceptable among this population. Clinical Relevance: Using mHealth appears feasible as an action-oriented tool for therapists to recommend for lifestyle self-monitoring in isolated rural men. The findings reinforce the important role of therapists in routinely assessing vital signs and making referrals as appropriate