595 research outputs found

    Die höchsten Energien im Universum

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    Possible Superconductivity at 37 K in Graphite-Sulfur Composite

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    Sulfur intercalated graphite composites with diamagnetic transitions at 6.7 K and 37 K are prepared. The magnetization hysteresis loops (MHL), Xray diffraction patterns, and resistance were measured. From the MHL, a slight superconducting like penetration process is observed at 15 K in low field region. The XRD shows no big difference from the mixture of graphite and sulfur indicating that the volume of the superconducting phase (if any) is very small. The temperature dependence of resistance shows a typical semiconducting behavior with a saturation in low temperature region. This saturation is either induced by the de-localization of conducting electrons or by possible superconductivity in this system.Comment: CHIN. PHYS.LETT v18 1648 (2001

    Multimodal Chemical Imaging of Amyloid Plaque Polymorphism Reveals A beta Aggregation Dependent Anionic Lipid Accumulations and Metabolism

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    Amyloid plaque formation constitutes one of the main pathological hallmarks of Alzheimer’s disease (AD) and is suggested to be a critical factor driving disease pathogenesis. Interestingly, in patients that display amyloid pathology but remain cognitively normal, Aβ deposits are predominantly of diffuse morphology suggesting that cored plaque formation is primarily associated with cognitive deterioration and AD pathogenesis. Little is known about the molecular mechanism responsible for conversion of monomeric Aβ into neurotoxic aggregates and the predominantly cored deposits observed in AD. The structural diversity among Aβ plaques, including cored/compact- and diffuse, may be linked to their distinct Aβ profile and other chemical species including neuronal lipids. We developed a novel, chemical imaging paradigm combining matrix assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) and fluorescent amyloid staining. This multimodal imaging approach was used to probe the lipid chemistry associated with structural plaque heterogeneity in transgenic AD mice (tgAPPSwe) and was correlated to Aβ profiles determined by subsequent laser microdissection and immunoprecipitation-mass spectrometry. Multivariate image analysis revealed an inverse localization of ceramides and their matching metabolites to diffuse and cored structures within single plaques, respectively. Moreover, phosphatidylinositols implicated in AD pathogenesis, were found to localize to the diffuse Aβ structures and correlate with Aβ1–42. Further, lysophospholipids implicated in neuroinflammation were increased in all Aβ deposits. The results support previous clinical findings on the importance of lipid disturbances in AD pathophysiology and associated sphingolipid processing. These data highlight the potential of multimodal imaging as a powerful technology to probe neuropathological mechanisms

    Recent advances in non-surgical management of cancer in the elderly [version 1; referees: 2 approved]

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    This article summarizes the seminal publications from mid-2016 through 2017 in the area of medical care for older adults with cancer. Areas addressed include chemotherapy tolerance and efficacy in the aged, geriatric fitness assessments, and advancements in palliative and supportive care. The practice-changing finding from this past year’s publications is that antipsychotics should not be used in the management of terminal delirium in older adults receiving palliative care. The other trials demonstrated an improved understanding of the utility of geriatric assessments in patients with cancer, developed the body of information about which chemotherapy agents are safe and effective in older adults (and which are not), and expanded our understanding of good palliative and supportive care

    Data Linkage to Improve Geriatric Oncology Research: A Feasibility Study

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    Older adults (aged 65 years and older) diagnosed with cancer account for most cancer‐related morbidity and mortality in the United States but are often underrepresented on clinical trials. Recent attention from a variety of professional, research, regulatory, and patient advocacy groups has centered on data linkage and data sharing as a means to capture patient information and outcomes outside of clinical trials to accelerate progress in the fight against cancer. The development of a more robust observational research data infrastructure would help to address gaps in the evidence base regarding optimal approaches to treating cancer among the growing and complex population of older adults. To demonstrate the feasibility of building such a resource, we linked information from a sample of older adults with cancer in North Carolina using three distinct, but complementary, data sources: (a) the Carolina Senior Registry, (b) the North Carolina Central Cancer Registry, and (c) North Carolina fee‐for‐service Medicare claims data. A description of the linkage process, metrics, and characteristics of the final cohort is reported. This study highlights the potential for data linkage to improve the characterization of health status among older adults with cancer and the possibility to conduct passive follow‐up for outcomes of interest over time. Extensions of these linkage efforts in partnership with other institutions will enhance our ability to generate evidence that can inform the management of older adults with cancer

    Determination of absolute neutrino masses from Z-bursts

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    Ultrahigh energy neutrinos (UHE\nu) scatter on relic neutrinos (R\nu) producing Z bosons, which can decay hadronically producing protons (Z-burst). We compare the predicted proton spectrum with the observed ultrahigh energy cosmic ray (UHECR) spectrum and determine the mass of the heaviest R\nu via a maximum likelihood analysis. Our prediction depends on the origin of the power-like part of the UHECR spectrum: m_\nu=2.75^{+1.28}_{-0.97} eV for Galactic halo and 0.26^{+0.20}_{-0.14} eV for extragalactic (EG) origin. The necessary UHE\nu flux should be detected in the near future.Comment: slight rewording, revised neutrino fluxes, conclusions unchanged, version to appear in Phys. Rev. Let

    Experimental Search for Solar Axions

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    A new technique has been used to search for solar axions using a single crystal germanium detector. It exploits the coherent conversion of axions into photons when their angle of incidence satisfies a Bragg condition with a crystalline plane. The analysis of approximately 1.94 kg.yr of data from the 1-kg DEMOS detector in Sierra Grande, Argentina, yields a new laboratory bound on axion-photon coupling of g_{a,\gamma\gamma}<2.7\times 10^{-9} GeV^{-1} independent of axion mass up to \sim 1 keV

    Geriatric assessment predicts hospitalization frequency and long-term care use in older adult cancer survivors

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    PURPOSE The association between geriatric assessment (GA)–identified impairments and long-term health care use in older cancer survivors remains unknown. Our objective was to evaluate whether a GA performed at cancer diagnosis was predictive of hospitalizations and long-term care (LTC) use in older adult cancer survivors. METHODS Older adults with GA performed between 3 months before through 6 months after diagnosis were included (N = 125). Patients with Medicare Parts A and B coverage and no managed care were identified. Hospitalizations and LTC use (skilled nursing or assisted living) were assessed up to 5 years postdiagnosis. GA risk measures were evaluated in separate Poisson models estimating the relative risk (RR) for hospital and LTC visits, adjusting for age and Charlson comorbidity score. RESULTS The mean age of patients was 74 years, and the majority were female (80%) and white (90%). Breast cancer (64%) and early-stage disease (stages 0 to III, 77%) were common. Prefrail/frail status (RR, 2.5; P, .001), instrumental activities of daily living impairment (RR, 5.47; P, .001), and limitations in climbing stairs (RR, 2.94; P, .001) were associated with increased hospitalizations. Prefrail/frail status (RR, 1.86; P, .007), instrumental activities of daily living impairment (RR, 4.58; P, .001), presence of falls (RR, 6.73; P, .001), prolonged Timed Up and Go (RR, 5.45; P, .001), and limitations in climbing stairs (RR, 1.89; P, .005) were associated with LTC use. CONCLUSION GA-identified impairments were associated with increased hospitalizations and LTC use among older adults with cancer. GA-focused interventions should be targeted toward high-risk patients to reduce long-term adverse health care use in this vulnerable population
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