786 research outputs found

    Gamma Lines without a Continuum: Thermal Models for the Fermi-LAT 130 GeV Gamma Line

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    Recent claims of a line in the Fermi-LAT photon spectrum at 130 GeV are suggestive of dark matter annihilation in the galactic center and other dark matter-dominated regions. If the Fermi feature is indeed due to dark matter annihilation, the best-fit line cross-section, together with the lack of any corresponding excess in continuum photons, poses an interesting puzzle for models of thermal dark matter: the line cross-section is too large to be generated radiatively from open Standard Model annihilation modes, and too small to provide efficient dark matter annihilation in the early universe. We discuss two mechanisms to solve this puzzle and illustrate each with a simple reference model in which the dominant dark matter annihilation channel is photonic final states. The first mechanism we employ is resonant annihilation, which enhances the annihilation cross-section during freezeout and allows for a sufficiently large present-day annihilation cross section. Second, we consider cascade annihilation, with a hierarchy between p-wave and s-wave processes. Both mechanisms require mass near-degeneracies and predict states with masses closely related to the dark matter mass; resonant freezeout in addition requires new charged particles at the TeV scale.Comment: 17 pages, 8 figure

    Focusing and Compression of Ultrashort Pulses through Scattering Media

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    Light scattering in inhomogeneous media induces wavefront distortions which pose an inherent limitation in many optical applications. Examples range from microscopy and nanosurgery to astronomy. In recent years, ongoing efforts have made the correction of spatial distortions possible by wavefront shaping techniques. However, when ultrashort pulses are employed scattering induces temporal distortions which hinder their use in nonlinear processes such as in multiphoton microscopy and quantum control experiments. Here we show that correction of both spatial and temporal distortions can be attained by manipulating only the spatial degrees of freedom of the incident wavefront. Moreover, by optimizing a nonlinear signal the refocused pulse can be shorter than the input pulse. We demonstrate focusing of 100fs pulses through a 1mm thick brain tissue, and 1000-fold enhancement of a localized two-photon fluorescence signal. Our results open up new possibilities for optical manipulation and nonlinear imaging in scattering media

    The U.S. training institute for dissemination and implementation research in health

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    Abstract Background The science of dissemination and implementation (D&I) is advancing the knowledge base for how best to integrate evidence-based interventions within clinical and community settings and how to recast the nature or conduct of the research itself to make it more relevant and actionable in those settings. While the field is growing, there are only a few training programs for D&I research; this is an important avenue to help build the field’s capacity. To improve the United States’ capacity for D&I research, the National Institutes of Health and Veterans Health Administration collaborated to develop a five-day training institute for postdoctoral level applicants aspiring to advance this science. Methods We describe the background, goals, structure, curriculum, application process, trainee evaluation, and future plans for the Training in Dissemination and Implementation Research in Health (TIDIRH). Results The TIDIRH used a five-day residential immersion to maximize opportunities for trainees and faculty to interact. The train-the-trainer-like approach was intended to equip participants with materials that they could readily take back to their home institutions to increase interest and further investment in D&I. The TIDIRH curriculum included a balance of structured large group discussions and interactive small group sessions. Thirty-five of 266 applicants for the first annual training institute were accepted from a variety of disciplines, including psychology (12 trainees); medicine (6 trainees); epidemiology (5 trainees); health behavior/health education (4 trainees); and 1 trainee each from education & human development, health policy and management, health services research, public health studies, public policy and social work, with a maximum of two individuals from any one institution. The institute was rated as very helpful by attendees, and by six months after the institute, a follow-up survey (97% return rate) revealed that 72% had initiated a new grant proposal in D&I research; 28% had received funding, and 77% had used skills from TIDIRH to influence their peers from different disciplines about D&I research through building local research networks, organizing formal presentations and symposia, teaching and by leading interdisciplinary teams to conduct D&I research. Conclusions The initial TIDIRH training was judged successful by trainee evaluation at the conclusion of the week’s training and six-month follow-up, and plans are to continue and possibly expand the TIDIRH in coming years. Strengths are seen as the residential format, quality of the faculty and their flexibility in adjusting content to meet trainee needs, and the highlighting of concrete D&I examples by the local host institution, which rotates annually. Lessons learned and plans for future TIDIRH trainings are summarized

    Efficient CO2-Reducing Activity of NAD-Dependent Formate Dehydrogenase from Thiobacillus sp KNK65MA for Formate Production from CO2 Gas

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    NAD-dependent formate dehydrogenase (FDH) from Candida boidinii (CbFDH) has been widely used in various CO2 reduction systems but its practical applications are often impeded due to low CO2-reducing activity. In this study, we demonstrated superior CO2-reducing properties of FDH from Thiobacillus sp. KNK65MA (TsFDH) for production of formate from CO2 gas. To discover more efficient CO2-reducing FDHs than a reference enzyme e. CbFDH, five FDHs were selected with biochemical properties and then, their CO2-reducing activities were evaluated. All FDHs including CbFDH showed better CO2-reducing activities at acidic pHs than at neutral pHs and four FDHs were more active than CbFDH in the CO2 reduction reaction. In particular, the FDH from Thiobacillus sp. KNK65IVIA (TsFDH) exhibited the highest CO2-reducing activity and had a dramatic preference for the reduction reaction, i.e., a 84.2-fold higher ratio of CO2 reduction to formate oxidation in catalytic efficiency (k(cat)/K-B) compared to CbFDH. Formate was produced from CO2 gas using TsFDH and CbFDH, and TsFDH showed a 5.8-fold higher formate production rate than CbFDH. A sequence and structural comparison showed that FDHs with relatively high CO2-reducing activities had elongated N- and C-terminal loops. The experimental results demonstrate that TsFDH can be an alternative to CbFDH as a biocatalyst in CO2 reduction systemsope

    Crowdsourced estimation of cognitive decline and resilience in Alzheimer's disease

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    Identifying accurate biomarkers of cognitive decline is essential for advancing early diagnosis and prevention therapies in Alzheimer's disease. The Alzheimer's disease DREAM Challenge was designed as a computational crowdsourced project to benchmark the current state-of-the-art in predicting cognitive outcomes in Alzheimer's disease based on high dimensional, publicly available genetic and structural imaging data. This meta-analysis failed to identify a meaningful predictor developed from either data modality, suggesting that alternate approaches should be considered for prediction of cognitive performance

    How Much Does Effortful Thinking Underlie Observers’ Reactions to Victimization?

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    From blaming to helping innocent victims, just-world research has revealed that observers react to victimization in a variety of ways. Recent research suggests that such responses to victimization require effortful thought, whereas other research has shown that people can react to these situations intuitively. Along with manipulating just-world threat, across seven experiments, we manipulated or measured participants’ level of mental processing before assessing judgments of victim derogation, blame, willingness to help, and ultimate justice reasoning. The effect of just-world threat on these responses held constant over a range of manipulations/measures, suggesting that the processes involved in maintaining a belief in a just world are not restricted to the rational, deliberative level of mental processing but also occur intuitively

    Integrated genomic characterization of oesophageal carcinoma

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    Oesophageal cancers are prominent worldwide; however, there are few targeted therapies and survival rates for these cancers remain dismal. Here we performed a comprehensive molecular analysis of 164 carcinomas of the oesophagus derived from Western and Eastern populations. Beyond known histopathological and epidemiologic distinctions, molecular features differentiated oesophageal squamous cell carcinomas from oesophageal adenocarcinomas. Oesophageal squamous cell carcinomas resembled squamous carcinomas of other organs more than they did oesophageal adenocarcinomas. Our analyses identified three molecular subclasses of oesophageal squamous cell carcinomas, but none showed evidence for an aetiological role of human papillomavirus. Squamous cell carcinomas showed frequent genomic amplifications of CCND1 and SOX2 and/or TP63, whereas ERBB2, VEGFA and GATA4 and GATA6 were more commonly amplified in adenocarcinomas. Oesophageal adenocarcinomas strongly resembled the chromosomally unstable variant of gastric adenocarcinoma, suggesting that these cancers could be considered a single disease entity. However, some molecular features, including DNA hypermethylation, occurred disproportionally in oesophageal adenocarcinomas. These data provide a framework to facilitate more rational categorization of these tumours and a foundation for new therapies.ope

    Doctor-patient communication in the e-health era

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    The digital revolution will have a profound impact on how physicians and health care delivery organizations interact with patients and the community at-large. Over the coming decades, face-to-face patient/doctor contacts will become less common and exchanges between consumers and providers will increasingly be mediated by electronic devices. In highly developed health care systems like those in Israel, the United States, and Europe, most aspects of the health care and consumer health experience are becoming supported by a wide array of technology such as electronic and personal health records (EHRs and PHRs), biometric & telemedicine devices, and consumer-focused wireless and wired Internet applications. In an article in this issue, Peleg and Nazarenko report on a survey they fielded within Israel's largest integrated delivery system regarding patient views on the use of electronic communication with their doctors via direct-access mobile phones and e-mail. A previous complementary paper describes the parallel perspectives of the physician staff at the same organization. These two surveys offer useful insights to clinicians, managers, researchers, and policymakers on how best to integrate e-mail and direct-to-doctor mobile phones into their practice settings. These papers, along with several other recent Israeli studies on e-health, also provide an opportunity to step back and take stock of the dramatic impact that information & communication technology (ICT) and health information technology (HIT) will have on clinician/patient communication moving forward. The main goals of this commentary are to describe the scope of this issue and to offer a framework for understanding the potential impact that e-health tools will have on provider/patient communication. It will be essential that clinicians, managers, policymakers, and researchers gain an increased understanding of this trend so that health care systems around the globe can adapt, adopt, and embrace these rapidly evolving digital technologies

    Renal ischemia–reperfusion injury causes intercalated cell-specific disruption of occludin in the collecting duct

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    Renal ischemic events open tight junctions and disrupt epithelial polarity. The purpose of this study was to examine the effects of ischemia–reperfusion (IR) injury on expression and distribution of the tight junction proteins, occludin and ZO-1, in the rat kidney. IR injury was induced by clamping both renal pedicles for 30 min and animals were killed at 6 h after the reperfusion. IR injury decreased blood bicarbonate level, but did not persistently alter pH, Na+, K+, or Cl−. In control kidneys, occludin immunoreactivity was intense in the tight junctions in the thick ascending limb, distal convoluted tubule, and collecting duct, moderate in the thin limbs of the loop of Henle, and was not detected in the proximal tubule, glomerulus, and blood vessels. ZO-1 was expressed in the same sites in which occludin was expressed, and additionally was also expressed in the proximal tubule, glomerulus, and vascular endothelial cells. IR kidneys exhibited damaged renal tubular epithelial cells in both proximal tubule and collecting duct segments in the outer medulla. In the collecting duct, the response of intercalated cells and principal cells differed. Following IR injury, intercalated cells, but not principal cells, lost their normal epithelial polarity and were frequently extruded into the tubule lumen. Occludin, instead of being localized to tight junctions, was localized diffusely in the cytoplasm in intercalated cells of IR kidneys. Principal cells, in contrast, were not detectably affected and neither occludin nor ZO-1 expression were altered in response to IR injury. The normal localization of ZO-1 expression to tight junction sites in both the proximal tubule and collecting duct was altered in response to IR, and, instead, ZO-1 expression was present diffusely in the cytoplasm. IR injury did not alter detectably either occludin or ZO-1 localization to the tight junction of the thick ascending limb cells. The abundance of total occludin protein by immunoblot analysis was not changed with IR injury. These results demonstrate that renal IR injury causes tight junction disruptions in both the proximal tubule and the collecting duct, and that altered distribution of the tight junction protein, occludin, may play a critical role in the collecting duct dysfunction which IR induces

    Health care costs, utilization and patterns of care following Lyme disease

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    BACKGROUND:Lyme disease is the most frequently reported vector borne infection in the United States. The Centers for Disease Control have estimated that approximately 10% to 20% of individuals may experience Post-Treatment Lyme Disease Syndrome - a set of symptoms including fatigue, musculoskeletal pain, and neurocognitive complaints that persist after initial antibiotic treatment of Lyme disease. Little is known about the impact of Lyme disease or post-treatment Lyme disease symptoms (PTLDS) on health care costs and utilization in the United States. OBJECTIVES:1) to examine the impact of Lyme disease on health care costs and utilization, 2) to understand the relationship between Lyme disease and the probability of developing PTLDS, 3) to understand how PTLDS may impact health care costs and utilization. METHODS:This study utilizes retrospective data on medical claims and member enrollment for persons aged 0-64 years who were enrolled in commercial health insurance plans in the United States between 2006-2010. 52,795 individuals treated for Lyme disease were compared to 263,975 matched controls with no evidence of Lyme disease exposure. RESULTS:Lyme disease is associated with 2,968highertotalhealthcarecosts(952,968 higher total health care costs (95% CI: 2,807-3,128, p<.001) and 87% more outpatient visits (95% CI: 86%-89%, p<.001) over a 12-month period, and is associated with 4.77 times greater odds of having any PTLDS-related diagnosis, as compared to controls (95% CI: 4.67-4.87, p<.001). Among those with Lyme disease, having one or more PTLDS-related diagnosis is associated with 3,798 higher total health care costs (95% CI: 3,542-4,055, p<.001) and 66% more outpatient visits (95% CI: 64%-69%, p<.001) over a 12-month period, relative to those with no PTLDS-related diagnoses. CONCLUSIONS:Lyme disease is associated with increased costs above what would be expected for an easy to treat infection. The presence of PTLDS-related diagnoses after treatment is associated with significant health care costs and utilization
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