The Chandra Dust Scattering Halo of Galactic Center transient Swift J174540.7-290015

We report the detection of a dust scattering halo around a recently discovered X-ray transient, Swift J174540.7-290015, which in early February of 2016 underwent one of the brightest outbursts (F_X ~ 5e-10 erg/cm^2/s) observed from a compact object in the Galactic Center field. We analyze four Chandra images that were taken as follow-up observations to Swift discoveries of new Galactic Center transients. After adjusting our spectral extraction for the effects of detector pileup, we construct a point spread function for each observation and compare it to the GC field before the outburst. We find residual surface brightness around Swift J174540.7-290015, which has a shape and temporal evolution consistent with the behavior expected from X-rays scattered by foreground dust. We examine the spectral properties of the source, which shows evidence that the object transitioned from a soft to hard spectral state as it faded below L_X ~ 1e36 erg/s. This behavior is consistent with the hypothesis that the object is a low mass X-ray binary in the Galactic Center.Comment: Accepted for publication in Ap

Estructura, fábrica magnética y emplazamiento de los granitos de Brealito y La Paya, basamento del valle Calchaquí, Salta, Argentina

Los granitoides de Brealito y La Paya son plutones de formas elípticas alargadas en dirección N-S emplazados respectivamente en las Formaciones Puncoviscana y La Paya. El estudio de la estructura interna de los plutones se ha abordado aplicando la anisotropía de la susceptibilidad magnética (ASM). El plutón de La Paya presenta un carácter paramagnético (K entre 1,9 y 6,7 x10- 5 SI) con una fábrica magnética controlada por la biotita, en cambio el plutón de Brealito muestra un carácter mixto (K entre 22 y 466 x10- 5 SI) con algunas estaciones en las que la contribución ferromagnética (originada por magnetita) es dominante. Las anisotropías totales medidas son coherentes con el carácter magmático de las muestras analizadas. Ambos plutones presentan semejanzas desde el punto de vista estructural. Son cuerpos de forma lenticular, concordantes con el encajante y buzando hacia el Oeste. La lineación magnética presenta buzamientos suaves en dirección N-S.The Brealito and La Paya granitoids are elliptical-shaped plutons with N-S elongation. They intrude into the Puncoviscana and La Paya Formations, respectively. The internal structure of these plutons has been studied by using field structures and applying the Anisotropy of the Magnetic Susceptibility (AMS). The magnetic fabric of the La Paya pluton reflects the orientation of biotite, the main paramagnetic mineral in this granite (K between 1.9 and 6.7 x10-5SI). Instead, the magnetic behavior of the Brealito granite is more complex since not only paramagnetic minerals, but also the ferromagnetic contribution (K between 22 and 466 x10-5SI) of magnetite crystals strongly control the magnetic fabric of some samples. Total anisotropy values of the magnetic fabrics are coherent with the magmatic nature of the analized samples. From the structural point of view, both plutons display similarities. These granites are lozenge-shaped bodies concordant with the host rocks. Their planar fabrics are mainly NS-trending and West dipping, and magnetic lineations plunge at low angles along the N-S direction

A systematic examination of preoperative surgery warm-up routines

Recent evidence indicates that a preoperative warm-up is a potentially useful tool in facilitating performance. But what factors drive such improvements and how should a warm-up be implemented?In order to address these issues, we adopted a two-pronged approach: (1) we conducted a systematic review of the literature to identify existing studies utilising preoperative simulation techniques; (2) we performed task analysis to identify the constituent parts of effective warm-ups. We identified five randomised control trials, four randomised cross-over trials and four case series. The majority of these studies reviewed surgical performance following preoperative simulation relative to performance without simulation.Four studies reported outcome measures in real patients and the remainder reported simulated outcome measures. All but one of the studies found that preoperative simulation improves operative outcomes-but this improvement was not found across all measured parameters. While the reviewed studies had a number of methodological issues, the global data indicate that preoperative simulation has substantial potential to improve surgical performance. Analysis of the task characteristics of successful interventions indicated that the majority of these studies employed warm-ups that focused on the visual motor elements of surgery. However, there was no theoretical or empirical basis to inform the design of the intervention in any of these studies.There is an urgent need for a more rigorous approach to the development of "warm-up" routines if the potential value of preoperative simulation is to be understood and realised. We propose that such interventions need to be grounded in theory and empirical evidence on human motor performance

Circadian rhythm of oestradiol: Impact on the bone metabolism of adult males

Background: Few studies have examined the variation in oestradiol with respect to age and circadian rhythm and the subsequent effects on BMD. Aim: Demonstrate the presence or absence of a circadian rhythm for oestrodial in older men and the integral role of concerted circadian rhythms of several factors including parathyroid hormone (PTH) in regulating biochemical markers of bone resorption and formation. Examine whether concentrations of both circulating total and bioavailable oestrogen in men differ with age and BMD. Design: Males were recruited: young men with normal BMD, older men with normal BMD and older men with osteoporosis. Methods: Subjects were hospitalized for a 25-hour period. Blood samples were obtained every 30 minutes. Hormone analysis results were plotted and reviewed. Results: Both total and bioavailable oestradiol concentrations were significantly lower in the older men than the young men (Total oestradiol: 34.5±4.4 pmol/L vs. 49.0±6.5 pmol/L, p<0.0001; Bioavailable oestradiol 16.7±2.2 pmol/L vs. 26.3±3.6 pmol/L, p<0.0001). Bioavailable oestrogen rhythm mirrored that of total estrogen. Conclusion: Both age groups with normal BMD display circadian rhythmicity with respect to circulating and bioavailable oestradiol. Younger men have increased mean total and bioavailable oestrogen concentrations and later acrophase compared to older counterparts. In older men with low BMD, total circulating oestrogen was not significantly different compared to age-matched older men with normal BMD; bioavailable oestrogen was significantly lower. Total oestrogen demonstrated a concerted circadian rhythm in all 3 groups, but bioavailable oestrogen did not demonstrate circadian rhythmicity in older men with decreased BMD

Histopathological study of JNK in venous wall of patients with chronic venous insufficiency related to osteogenesis process

Chronic venous insufficiency (CVI) is one of the most common vascular pathologies worldwide. One of the risk factors for the development of CVI is aging, which is why it is related to senile changes. The main trigger of the changes that occur in the venous walls in CVI is blood flow reflux, which produces increased hydrostatic pressure, leading to valve incompetence. The cellular response is one of the fundamental processes in vascular diseases, causing the activation of cell signalling pathways such as c-Jun N-terminal kinase (JNK). Metabolic changes and calcifications occur in vascular pathology as a result of pathophysiological processes. The aim of this study was to determine the expression of JNK in venous disease and its relationship with the role played by the molecules involved in the osteogenic processes in venous tissue calcification. This was a cross-sectional study that analyzed the greater saphenous vein wall in 110 patients with (R) and without venous reflux (NR), classified according to age. Histopathological techniques were used and protein expression was analysed using immunohistochemistry techniques for JNK and markers of osteogenesis (RUNX2, osteocalcin (OCN), osteopontin (OPN)). Significantly increased JNK, RUNX2, OCN, OPN and pigment epithelium-derived factor (PEDF) protein expression and the presence of osseous metaplasia and amorphous calcification were observed in younger patients (<50 years) with venous reflux. This study shows for the first time the existence of an osteogenesis process related to the expression of JNK in the venous wall.This study (FIS-PI18/00912) was supported by the Instituto de Salud Carlos III (Plan Estatal de I+D+i 2013-2016) and cofinanced by the European Development Regional Fund ‘‘A way to achieve Europe’’ (ERDF) and B2017/BMD-3804 MITIC-C

Eating Disorder Awareness Campaigns:Thematic and Quantitative Analysis Using Twitter

Background: Health awareness initiatives are frequent but their efficacy is a matter of controversy. We have investigated the effect of the Eating Disorder Awareness Week and Wake Up Weight Watchers campaigns on Twitter. Objective: We aimed to examine whether the Eating Disorder Awareness Week and Wake Up Weight Watchers initiatives increased the volume and dissemination of Twitter conversations related to eating disorders and investigate what content generates the most interest on Twitter. Methods: Over a period of 12 consecutive days in 2018, we collected tweets containing the hashtag #wakeupweightwatchers and hashtags related to Eating Disorder Awareness Week (#eatingdisorderawarenessweek, #eatingdisorderawareness, or #EDAW), with the hashtag #eatingdisorder as a control. The content of each tweet was rated as medical, testimony, help offer, awareness, pro-ana, or anti-ana. We analyzed the number of retweets and favorites generated, as well as the potential reach and impact of the hashtags and the characteristics of contributors. Results: The number of #wakeupweightwatchers tweets was higher than that of Eating Disorder Awareness Week and #eatingdisorder tweets (3900, 2056, and 1057, respectively). The content of tweets was significantly different between the hashtags analyzed (P<.001). Medical content was lower in the awareness campaigns. Awareness and help offer content were lower in #wakeupweightwatchers tweets. Retweet and favorite ratios were highest in #wakeupweightwatchers tweets. Eating Disorder Awareness Week achieved the highest impact, and very influential contributors participated. Conclusions: Both awareness campaigns effectively promoted tweeting about eating disorders. The majority of tweets did not promote any specific preventive or help-seeking behaviors

Intact automatic avoidance of obstacles in patients with visual form agnosia

In everyday life our reaching behaviour has to be guided not only by the location and properties of the target object, but also by the presence of potential obstacles in the workspace. Recent evidence from neglect and optic ataxia patients has suggested that this automatic obstacle avoidance is mediated by the dorsal, rather than the ventral, stream of visual processing. We tested this idea in two studies involving patients with visual form agnosia resulting from bilateral ventral-stream damage. In the first study, we asked patient DF to reach out and pick up a target object in the presence of obstacles placed at varying distances to the left or right of the target. We found that both DF and controls shifted their trajectories away from the potential obstacles and adjusted their grip aperture in such a way as to minimize risk of collision. In a second study, we asked DF and a second patient, SB, to either reach between, or to bisect the space between, two cylinders presented at varying locations. We found that both patients adjusted their reach trajectories to account for shifts in cylinder location in the reaching task, despite showing significantly worse performance than control subjects when asked to make a bisection judgement. Taken together, these data indicate that automatic obstacle avoidance behaviour is spared in our patients with visual form agnosia. We attribute their ability to the functional intactness of the dorsal stream of visual processing, and argue that the ventral stream plays no important role in automatic obstacle avoidance

Profile and width of rough interfaces

In the context of Landau theory and its field theoretical refinements, interfaces between coexisting phases are described by intrinsic profiles. These intrinsic interface profiles, however, are neither directly accessible by experiment nor by computer simulation as they are broadened by long-wavelength capillary waves. In this paper we study the separation of the small scale intrinsic structure from the large scale capillary wave fluctuations in the Monte Carlo simulated three-dimensional Ising model. To this purpose, a blocking procedure is applied, using the block size as a variable cutoff, and a translationally invariant method to determine the interface position of strongly fluctuating profiles on small length scales is introduced. While the capillary wave picture is confirmed on large length scales and its limit of validity is estimated, an intrinsic regime is, contrary to expectations, not observed.Comment: 18 pages, 4 Postscript figures, LaTeX2e, formulation of sec.3.2 improved, 1 reference adde

Logarithmic corrections in the two-dimensional Ising model in a random surface field

In the two-dimensional Ising model weak random surface field is predicted to be a marginally irrelevant perturbation at the critical point. We study this question by extensive Monte Carlo simulations for various strength of disorder. The calculated effective (temperature or size dependent) critical exponents fit with the field-theoretical results and can be interpreted in terms of the predicted logarithmic corrections to the pure system's critical behaviour.Comment: 10 pages, 4 figures, extended version with one new sectio