Dynamic test results for the CASES ground experiment

The Controls, Astrophysics, and Structures Experiment in Space (CASES) Ground Test Facility (GTF) has been developed at Marshall Space Flight Center (MSFC) to provide a facility for the investigation of Controls/Structures Interaction (CSI) phenomena, to support ground testing of a potential shuttle-based CASES flight experiment, and to perform limited boom deployment and retraction dynamics studies. The primary objectives of the ground experiment are to investigate CSI on a test article representative of a Large Space Structure (LSS); provide a platform for Guest Investigators (GI's) to conduct CSI studies; to test and evaluate LSS control methodologies, system identification (ID) techniques, failure mode analysis; and to compare ground test predictions and flight results. The proposed CASES flight experiment consists of a 32 meter deployable/retractable boom at the end of which is an occulting plate. The control objective of the experiment is to maintain alignment of the tip plate (occulter) with a detector located at the base of the boom in the orbiter bay. The tip plate is pointed towards a star, the sun, or the galactic center to collect high-energy X-rays emitted by these sources. The tip plate, boom, and detector comprise a Fourier telescope. The occulting holes in the tip plate are approximately one millimeter in diameter making the alignment requirements quite stringent. Control authority is provided by bidirectional linear thrusters located at the boom tip and Angular Momentum Exchange Devices (AMED's) located at mid-boom and at the tip. The experiment embodies a number of CSI control problems including vibration suppression, pointing a long flexible structure, and disturbance rejection. The CASES GTF is representative of the proposed flight experiment with identical control objectives

When to approach novel prey cues? Social learning strategies in frog-eating bats

Animals can use different sources of information when making decisions. Foraging animals often have access to both self-acquired and socially acquired information about prey. The fringe-lipped bat, Trachops cirrhosus, hunts frogs by approaching the calls that frogs produce to attract mates.We examined howthe reliability of self-acquired prey cues affects social learning of novel prey cues. We trained bats to associate an artificial acoustic cue (mobile phone ringtone) with food rewards. Bats were assigned to treatments in which the trained cue was either an unreliable indicator of reward (rewarded 50% of the presentations) or a reliable indicator (rewarded 100% of the presentations), and they were exposed to a conspecific tutor foraging on a reliable (rewarded 100%) novel cue or to the novel cue with no tutor. Bats whose trained cue was unreliable and who had a tutor were significantly more likely to preferentially approach the novel cue when compared with bats whose trained cue was reliable, and to bats that had no tutor. Reliability of self-acquired prey cues therefore affects social learning of novel prey cues by frog-eating bats. Examining when animals use social information to learn about novel prey is key to understanding the social transmission of foraging innovations. © 2013 The Author(s) Published by the Royal Society

Perception of the Importance of Traditional Country Foods to the Physical, Mental, and Spiritual Health of Labrador Inuit

Country foods play an integral role in Inuit life by providing nutrition and a spiritual connection to the land. However, they can harbour foodborne pathogens, such as zoonotic parasites or bacteria, which can cause disease in humans who consume contaminated meat that has been inadequately cooked. Given the heavy reliance of Inuit on subsistence living, it is important to have a clear understanding of the relative safety of these foods and the role that they play in a changing Inuit society. This community-based participatory research project involved Inuit residents of Nain, Nunatsiavut, Canada. Data on Inuit perceptions of the role, importance, and safety of country foods were collected during a series of interviews with focus groups and key informants. Despite the extremely positive views they expressed about country foods and the connections they provide to the land, community, and past, participants had major concerns about human expansion in the North, mining operations, chemical contamination, and the impact of these issues on animals and the food harvested from those animals. Also of concern was a perceived decrease in the importance of country food in their community in general, and specifically among children. These findings provide an understanding of Nunatsiavut residents’ perceptions that is essential to planning effective, culturally appropriate dissemination of public health messages about the safe consumption of country foods.La nourriture de campagne revêt une grande importance dans la vie des Inuits car elle présente à la fois une source de nutrition de même qu’un attachement spirituel à la terre. Cependant, cette nourriture peut être assortie de pathogènes d’origine alimentaire prenant notamment la forme de parasites ou de bactéries zoonotiques qui peuvent entraîner des maladies chez l’être humain qui consomme de la viande contaminée dont la cuisson n’est pas adéquate. Étant donné la grande dépendance des Inuits par rapport à l’alimentation de subsistance, il est important de bien comprendre la salubrité relative de ces aliments et du rôle qu’ils jouent au sein de la société inuite en pleine évolution. Ce projet de recherche communautaire a fait appel à des habitants inuits de Nain, Nunatsiavut, au Canada. Des données relatives aux perceptions des Inuits sur le rôle, l’importance et la salubrité de la nourriture de campagne ont été recueillies dans le cadre d’une série d’entrevues réalisées auprès de groupes de discussion et d’intervenants-clés. Malgré les points de vue extrêmement positifs exprimés au sujet de la nourriture de campagne et de l’attachement qu’elle procure à la terre, à la collectivité et au passé, les participants ont exprimé de grandes préoccupations à propos de l’expansion humaine dans le Nord, de l’exploitation minière, de la contamination chimique et de l’incidence de ces enjeux sur les animaux et les sources de nourriture provenant de ces animaux. Par ailleurs, ils s’inquiétaient de la diminution perçue de l’importance de la nourriture de campagne au sein de leur communauté en général, plus précisément chez les enfants. Ces constatations permettent de comprendre les perceptions des habitants de Nunatsiavut, ce qui est essentiel à une planification efficace et à la dissémination culturellement appropriée des messages de santé publique au sujet de la consommation sécuritaire de la nourriture de campagne

Antibiotic resistance among clinical Ureaplasma Isolates Recovered from Neonates in England and Wales between 2007 and 2013

Ureaplasma spp. are associated with numerous clinical sequelae with treatment options being limited due to patient and pathogen factors. This report examines the prevalence and mechanisms of antibiotic resistance among clinical strains isolated from 95 neonates, 32 women attending a sexual health clinic, and 3 patients under investigation for immunological disorders, between 2007 and 2013 in England and Wales. MICs were determined by using broth microdilution assays, and a subset of isolates were compared using the broth microdilution method and the Mycoplasma IST2 assay. The underlying molecular mechanisms for resistance were determined for all resistant isolates. Three isolates carried the tet(M) tetracycline resistance gene (2.3%; confidence interval [CI], 0.49 to 6.86%); two isolates were ciprofloxacin resistant (1.5%; CI, 0.07 to 5.79%) but sensitive to levofloxacin and moxifloxacin, while no resistance was seen to any macrolides tested. The MIC values for chloramphenicol were universally low (2 μg/ml), while inherently high-level MIC values for gentamicin were seen (44 to 66 μg/ml). The Mycoplasma IST2 assay identified a number of false positives for ciprofloxacin resistance, as the method does not conform to international testing guidelines. While antibiotic resistance among Ureaplasma isolates remains low, continued surveillance is essential to monitor trends and threats from importation of resistant clones

Plasma heat shock protein 27 is associated with coronary artery disease, abdominal aortic aneurysm and peripheral artery disease

Low protein levels of Hsp27 have been reported in atherosclerotic plaques. In addition, human studies have indicated that circulating Hsp27 levels are lower in coronary artery disease patients compared with controls. It remains, however, unclear whether this applies to other forms of atherosclerotic disease. Plasma Hsp27 from 280 subjects was examined by ELISA. The cohort included 80 coronary artery disease (CAD), 40 peripheral artery disease (PAD) and 80 abdominal aortic aneurysm (AAA) patients. Eighty elderly subjects, without any clinical history of vascular diseases, were used as a control group. Receiver operating curve (ROC) and logistic regression model analysis were performed to evaluate the potential value of Hsp27 as a circulating biomarker. Patients with atherosclerotic vascular diseases had significantly lower levels of Hsp27 than control subjects (p < 0.001). Moreover, Hsp27 was significantly lower in CAD patients than other atherosclerotic vascular disease groups (p < 0.001). There was no difference in Hsp27 levels between the AAA and PAD groups. Using the ROC-generated optimal cut-off values for Hsp27, logistic regression modeling indicated that low plasma Hsp27 was independently associated with the presence of multiple forms of atherosclerotic disease. In conclusion, circulating Hsp27 is significantly lower in patients with multiple forms of atherosclerotic arterial disease

School playgrounds and physical activity policies as predictors of school and home time activity

<p>Abstract</p> <p>Background</p> <p>Previous work has suggested that the number of permanent play facilities in school playgrounds and school-based policies on physical activity can influence physical activity in children. However, few comparable studies have used objective measures of physical activity or have had little adjustment for multiple confounders.</p> <p>Methods</p> <p>Physical activity was measured by accelerometry over 5 recess periods and 3 full school days in 441 children from 16 primary schools in Dunedin, New Zealand. The number of permanent play facilities (swing, fort, slide, obstacle course, climbing wall etc) in each school playground was counted on three occasions by three researchers following a standardized protocol. Information on school policies pertaining to physical activity and participation in organized sport was collected by questionnaire.</p> <p>Results</p> <p>Measurement of school playgrounds proved to be reliable (ICC 0.89) and consistent over time. Boys were significantly more active than girls (P < 0.001), but little time overall was spent in moderate-vigorous physical activity (MVPA). Boys engaged in MVPA for 32 (SD 17) minutes each day of which 17 (10) took place at school compared with 23 (14) and 11 (7) minutes respectively in girls. Each additional 10-unit increase in play facilities was associated with 3.2% (95% CI 0.0-6.4%) more total activity and 8.3% (0.8-16.3%) more MVPA during recess. By contrast, school policy score was not associated with physical activity in children.</p> <p>Conclusion</p> <p>The number of permanent play facilities in school playgrounds is associated with higher physical activity in children, whereas no relationship was observed for school policies relating to physical activity. Increasing the number of permanent play facilities may offer a cost-effective long-term approach to increasing activity levels in children.</p

Criteria for arrhythmogenicity in genetically-modified Langendorff-perfused murine hearts modelling the congenital long QT syndrome type 3 and the Brugada syndrome

The experiments investigated the applicability of two established criteria for arrhythmogenicity in Scn5a+/Δ and Scn5a+/− murine hearts modelling the congenital long QT syndrome type 3 (LQT3) and the Brugada syndrome (BrS). Monophasic action potentials (APs) recorded during extrasystolic stimulation procedures from Langendorff-perfused control hearts and hearts treated with flecainide (1 μM) or quinidine (1 or 10 μM) demonstrated that both agents were pro-arrhythmic in wild-type (WT) hearts, quinidine was pro-arrhythmic in Scn5a+/Δ hearts, and that flecainide was pro-arrhythmic whereas quinidine was anti-arrhythmic in Scn5a+/− hearts, confirming clinical findings. Statistical analysis confirmed a quadratic relationship between epicardial and endocardial AP durations (APDs) in WT control hearts. However, comparisons between plots of epicardial against endocardial APDs and this reference curve failed to correlate with arrhythmogenicity. Restitution curves, relating APD to diastolic interval (DI), were then constructed for the first time in a murine system and mono-exponential growth functions fitted to these curves. Significant (P < 0.05) alterations in the DI at which slopes equalled unity, an established indicator of arrhythmogenicity, now successfully predicted the presence or absence of arrhythmogenicity in all cases. We thus associate changes in the slopes of restitution curves with arrhythmogenicity in models of LQT3 and BrS

Fresh Activity in Old Systems: Radio AGN in Fossil Groups of Galaxies

We present the first systematic 1.4 GHz Very Large Array radio continuum survey of fossil galaxy group candidates. These are virialized systems believed to have assembled over a gigayear in the past through the merging of galaxy group members into a single, isolated, massive elliptical galaxy and featuring an extended hot X-ray halo. We use new photometric and spectroscopic data from SDSS Data Release 7 to determine that three of the candidates are clearly not fossil groups. Of the remaining 30 candidates, 67% contain a radio-loud (L_1.4GHz > 10^23 W Hz^-1) active galactic nucleus (AGN) at the center of their dominant elliptical galaxy. We find a weak correlation between the radio luminosity of the AGN and the X-ray luminosity of the halo suggesting that the AGN contributes to energy deposition into the intragroup medium. We only find a correlation between the radio and optical luminosity of the central elliptical galaxy when we include X-ray selected, elliptically dominated non-fossil groups, indicating a weak relationship between AGN strength and the mass assembly history of the groups. The dominant elliptical galaxy of fossil groups is on average roughly an order of magnitude more luminous than normal group elliptical galaxies in optical, X-ray, and radio luminosities and our findings are consistent with previous results that the radio-loud fraction in elliptical galaxies is linked to the stellar mass of a population. The current level of activity in fossil groups suggests that AGN fueling continues long after the last major merger. We discuss several possibilities for fueling the AGN at the present epoch.Comment: Accepted for publication in A

Environmental Exposures during Puberty: Window of Breast Cancer Risk and Epigenetic Damage.

During puberty, a woman's breasts are vulnerable to environmental damage ("window of vulnerability"). Early exposure to environmental carcinogens, endocrine disruptors, and unhealthy foods (refined sugar, processed fats, food additives) are hypothesized to promote molecular damage that increases breast cancer risk. However, prospective human studies are difficult to perform and effective interventions to prevent these early exposures are lacking. It is difficult to prevent environmental exposures during puberty. Specifically, young women are repeatedly exposed to media messaging that promotes unhealthy foods. Young women living in disadvantaged neighborhoods experience additional challenges including a lack of access to healthy food and exposure to contaminated air, water, and soil. The purpose of this review is to gather information on potential exposures during puberty. In future directions, this information will be used to help elementary/middle-school girls to identify and quantitate environmental exposures and develop cost-effective strategies to reduce exposures