Propulsion simulation for magnetically suspended wind tunnel models

The feasibility of simulating propulsion-induced aerodynamic effects on scaled aircraft models in wind tunnels employing Magnetic Suspension and Balance Systems. The investigation concerned itself with techniques of generating exhaust jets of appropriate characteristics. The objectives were to: (1) define thrust and mass flow requirements of jets; (2) evaluate techniques for generating propulsive gas within volume limitations imposed by magnetically-suspended models; (3) conduct simple diagnostic experiments for techniques involving new concepts; and (4) recommend experiments for demonstration of propulsion simulation techniques. Various techniques of generating exhaust jets of appropriate characteristics were evaluated on scaled aircraft models in wind tunnels with MSBS. Four concepts of remotely-operated propulsion simulators were examined. Three conceptual designs involving innovative adaptation of convenient technologies (compressed gas cylinders, liquid, and solid propellants) were developed. The fourth innovative concept, namely, the laser-assisted thruster, which can potentially simulate both inlet and exhaust flows, was found to require very high power levels for small thrust levels

A Radio Pulsar/X-ray Binary Link

Radio pulsars with millisecond spin periods are thought to have been spun up by transfer of matter and angular momentum from a low-mass companion star during an X-ray-emitting phase. The spin periods of the neutron stars in several such low-mass X-ray binary (LMXB) systems have been shown to be in the millisecond regime, but no radio pulsations have been detected. Here we report on detection and follow-up observations of a nearby radio millisecond pulsar (MSP) in a circular binary orbit with an optically identified companion star. Optical observations indicate that an accretion disk was present in this system within the last decade. Our optical data show no evidence that one exists today, suggesting that the radio MSP has turned on after a recent LMXB phase.Comment: published in Scienc

Geodetic Brane Gravity

Within the framework of geodetic brane gravity, the Universe is described as a 4-dimensional extended object evolving geodetically in a higher dimensional flat background. In this paper, by introducing a new pair of canonical fields {lambda, P_{lambda}}, we derive the quadratic Hamiltonian for such a brane Universe; the inclusion of matter then resembles minimal coupling. Second class constraints enter the game, invoking the Dirac bracket formalism. The algebra of the first class constraints is calculated, and the BRST generator of the brane Universe turns out to be rank-1. At the quantum level, the road is open for canonical and/or functional integral quantization. The main advantages of geodetic brane gravity are: (i) It introduces an intrinsic, geometrically originated, 'dark matter' component, (ii) It offers, owing to the Lorentzian bulk time coordinate, a novel solution to the 'problem of time', and (iii) It enables calculation of meaningful probabilities within quantum cosmology without any auxiliary scalar field. Intriguingly, the general relativity limit is associated with lambda being a vanishing (degenerate) eigenvalue.Comment: 23 pages, 1 figure, minor change

Internet‐Based Pain Self‐Management for Veterans: Feasibility and Preliminary Efficacy of the Pain EASE Program

ObjectiveTo develop and test the feasibility and preliminary efficacy of a cognitive behavioral therapy–based, internet‐delivered self‐management program for chronic low back pain (cLBP) in veterans.MethodsPhase I included program development, involving expert panel and participant feedback. Phase II was a single‐arm feasibility and preliminary efficacy study of the Pain e‐health for Activity, Skills, and Education (Pain EASE) program. Feasibility (ie, website use, treatment credibility, satisfaction) was measured using descriptive methods. Mixed models were used to assess mean within‐subject changes from baseline to 10 weeks post‐baseline in pain interference (primary outcome, West Haven‐Yale Multidimensional Pain Inventory, scale of 0 to 6), pain intensity, mood, fatigue, sleep, and depression.ResultsPhase I participants (n = 15) suggested modifications including style changes, content reduction, additional “Test Your Knowledge” quizzes, and cognitive behavioral therapy skill practice monitoring form revisions for enhanced usability. In Phase II, participants (n = 58) were mostly male (93%) and White (60%), and had an average age of 55 years (standard deviation [SD] = 12) and moderate pain (mean score 5.9/10); 41 (71%) completed the post‐baseline assessment. Participants (N = 58) logged on 6.1 (SD = 8.6) times over 10 weeks, and 85% reported being very or moderately satisfied with Pain EASE. Pain interference improved from a mean of 3.8 at baseline to 3.3 at 10 weeks (difference 0.5 [95% confidence interval 0.1 to 0.9], P = 0.008). Within‐subject improvement also occurred for some secondary outcomes, including mood and depression symptoms.DiscussionVeterans with cLBP may benefit from technology‐delivered interventions, which may also reduce pain interference. Overall, veterans found that Pain EASE, an internet‐based self‐management program, is feasible and satisfactory for cLBP.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154929/1/papr12861.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154929/2/papr12861_am.pd

Assessing Usual Care in Clinical Trials

Researchers designing clinical trials often specify usual care received by participants as the control condition expecting that all participants receive usual care regardless of group assignment. The assumption is that the groups in the study are affected similarly. We describe the assessment of usual care within the 16 studies in MACH 14, a multi-site collaboration on adherence to antiretroviral therapy. Only five of the studies in MACH 14 assessed usual care. Assessment protocols varied as did the timing and frequency of assessments. All usual care assessments addressed patient education focused on HIV, HIV medications, and medication adherence. Our findings support earlier work that calls for systematic assessments of usual care within the study design, inclusion of descriptions of usual care in reports of the study, and the influence of usual care on the experimental condition in clinical trials

Assessing Usual Care in Clinical Trials

Researchers designing clinical trials often specify usual care received by participants as the control condition expecting that all participants receive usual care regardless of group assignment. The assumption is that the groups in the study are affected similarly. We describe the assessment of usual care within the 16 studies in MACH 14, a multi-site collaboration on adherence to antiretroviral therapy. Only five of the studies in MACH 14 assessed usual care. Assessment protocols varied as did the timing and frequency of assessments. All usual care assessments addressed patient education focused on HIV, HIV medications, and medication adherence. Our findings support earlier work that calls for systematic assessments of usual care within the study design, inclusion of descriptions of usual care in reports of the study, and the influence of usual care on the experimental condition in clinical trials

Changes in salivary estradiol predict changes in women’s preferences for vocal masculinity

Although many studies have reported that women’s preferences for masculine physical characteristics in men change systematically during the menstrual cycle, the hormonal mechanisms underpinning these changes are currently poorly understood. Previous studies investigating the relationships between measured hormone levels and women’s masculinity preferences tested only judgments of men’s facial attractiveness. Results of these studies suggested that preferences for masculine characteristics in men’s faces were related to either women’s estradiol or testosterone levels. To investigate the hormonal correlates of within-woman variation in masculinity preferences further, here we measured 62 women’s salivary estradiol, progesterone, and testosterone levels and their preferences for masculine characteristics in men’s voices in five weekly test sessions. Multilevel modeling of these data showed that changes in salivary estradiol were the best predictor of changes in women’s preferences for vocal masculinity. These results complement other recent research implicating estradiol in women’s mate preferences, attention to courtship signals, sexual motivation, and sexual strategies, and are the first to link women’s voice preferences directly to measured hormone levels

Changes in salivary estradiol predict changes in women’s preferences for vocal masculinity

Although many studies have reported that women’s preferences for masculine physical characteristics in men change systematically during the menstrual cycle, the hormonal mechanisms underpinning these changes are currently poorly understood. Previous studies investigating the relationships between measured hormone levels and women’s masculinity preferences tested only judgments of men’s facial attractiveness. Results of these studies suggested that preferences for masculine characteristics in men’s faces were related to either women’s estradiol or testosterone levels. To investigate the hormonal correlates of within-woman variation in masculinity preferences further, here we measured 62 women’s salivary estradiol, progesterone, and testosterone levels and their preferences for masculine characteristics in men’s voices in five weekly test sessions. Multilevel modeling of these data showed that changes in salivary estradiol were the best predictor of changes in women’s preferences for vocal masculinity. These results complement other recent research implicating estradiol in women’s mate preferences, attention to courtship signals, sexual motivation, and sexual strategies, and are the first to link women’s voice preferences directly to measured hormone levels