742 research outputs found
Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma in Older Adults
Multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) are plasma cell disorders of aging. The landscape of the diagnosis and management of MM and MGUS are rapidly changing. This article provides an updated understanding of the clinical presentation, evaluation, diagnosis, and management of older adults with MM and MGUS. Because most oncology providers are not formally trained in geriatric medicine, geriatricians play a key role in providing oncologists with a broader understanding of patient health status in the hope of improving outcomes for older adults with MM
Study of a high spatial resolution 10B-based thermal neutron detector for application in neutron reflectometry: the Multi-Blade prototype
Although for large area detectors it is crucial to find an alternative to
detect thermal neutrons because of the 3He shortage, this is not the case for
small area detectors. Neutron scattering science is still growing its
instruments' power and the neutron flux a detector must tolerate is increasing.
For small area detectors the main effort is to expand the detectors'
performances. At Institut Laue-Langevin (ILL) we developed the Multi-Blade
detector which wants to increase the spatial resolution of 3He-based detectors
for high flux applications. We developed a high spatial resolution prototype
suitable for neutron reflectometry instruments. It exploits solid 10B-films
employed in a proportional gas chamber. Two prototypes have been constructed at
ILL and the results obtained on our monochromatic test beam line are presented
here
Some Restrictions Abroad Affecting Corporations
A neutron detector concept based on solid layers of boron carbide enriched in 1 B has been in development for the last few years as an alternative for He-3 by collaboration between the ILL, ESS and Linkoping University. This Multi-Grid detector uses layers of aluminum substrates coated with (B4C)-B-10 on both sides that are traversed by the incoming neutrons. Detection is achieved using a gas counter readout principle. By segmenting the substrate and using multiple anode wires, the detector is made inherently position sensitive. This development is aimed primarily at neutron scattering instruments with large detector areas, such as time-of-flight chopper spectrometers. The most recent prototype has been built to be interchangeable with the He-3 detectors of IN6 at ILL. The 1 B detector has an active area of 32 x 48 cm(2). It was installed at the IN6 instrument and operated for several weeks, collecting data in parallel with the regularly scheduled experiments, thus providing the first side-by-side comparison with the conventional He-3 detectors. Results include an efficiency comparison, assessment of the in-detector scattering contribution, sensitivity to gamma-rays and the signal-to-noise ratio in time-of-flight spectra. The good expected performance has been confirmed with the exception of an unexpected background count rate. This has been identified as natural alpha activity in aluminum. New convertor substrates are under study to eliminate this source of background
A comparison of transgenic rodent mutation and in vivo comet assay responses for 91 chemicals.
A database of 91 chemicals with published data from both transgenic rodent mutation (TGR) and rodent comet assays has been compiled. The objective was to compare the sensitivity of the two assays for detecting genotoxicity. Critical aspects of study design and results were tabulated for each dataset. There were fewer datasets from rats than mice, particularly for the TGR assay, and therefore, results from both species were combined for further analysis. TGR and comet responses were compared in liver and bone marrow (the most commonly studied tissues), and in stomach and colon evaluated either separately or in combination with other GI tract segments. Overall positive, negative, or equivocal test results were assessed for each chemical across the tissues examined in the TGR and comet assays using two approaches: 1) overall calls based on weight of evidence (WoE) and expert judgement, and 2) curation of the data based on a priori acceptability criteria prior to deriving final tissue specific calls. Since the database contains a high prevalence of positive results, overall agreement between the assays was determined using statistics adjusted for prevalence (using AC1 and PABAK). These coefficients showed fair or moderate to good agreement for liver and the GI tract (predominantly stomach and colon data) using WoE, reduced agreement for stomach and colon evaluated separately using data curation, and poor or no agreement for bone marrow using both the WoE and data curation approaches. Confidence in these results is higher for liver than for the other tissues, for which there were less data. Our analysis finds that comet and TGR generally identify the same compounds (mainly potent mutagens) as genotoxic in liver, stomach and colon, but not in bone marrow. However, the current database content precluded drawing assay concordance conclusions for weak mutagens and non-DNA reactive chemicals
Assessing medical student knowledge and attitudes about shared decision making across the curriculum: protocol for an international online survey and stakeholder analysis
Introduction: Shared decision making (SDM) is a goal of modern medicine; however, it is not currently embedded in routine care. Barriers include clinicians’ attitudes, lack of knowledge and training and time constraints. Our goal is to support the development and delivery of a robust SDM curriculum in medical education. Our objective is to assess undergraduate medical students’ knowledge of and attitudes towards SDM in four countries.
Methods and analysis: The first phase of the study involves a web-based cross-sectional survey of undergraduate medical students from all years in selected schools across the United States (US), Canada and undergraduate and graduate students in the Netherlands. In the United Kingdom (UK), the survey will be circulated to all medical schools through the UK Medical School Council. We will sample students equally in all years of training and assess attitudes towards SDM, knowledge of SDM and participation in related training. Medical students of ages 18 years and older in the four countries will be eligible. The second phase of the study will involve semistructured interviews with a subset of students from phase 1 and a convenience sample of medical school curriculum experts or stakeholders. Data will be analysed using multivariable analysis in phase 1 and thematic content analysis in phase 2. Method, data source and investigator triangulation will be performed. Online survey data will be reported according to the Checklist for Reporting the Results of Internet E-Surveys. We will use the COnsolidated criteria for REporting Qualitative research for all qualitative data.
Ethics and dissemination: The study has been approved for dissemination in the US, the Netherlands, Canada and the UK. The study is voluntary with an informed consent process. The results will be published in a peer-reviewed journal and will help inform the inclusion of SDM-specific curriculum in medical education worldwide
Determination of absolute neutrino masses from Z-bursts
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
Falls in Older Adults With Cancer: Evaluation by Oncology Providers
Falls in older adults are common. Screening for falls is quick, simple, and important because falls increase the risk of morbidity and mortality in older patients with cancer. The aim of this study was to evaluate oncology providers' recognition of and response to falls in older patients with cancer
Experimental Search for Solar Axions
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
Grand Unification Signal from Ultra High Energy Cosmic Rays?
The spectrum of ultrahigh energy (above \approx 10^{9} GeV) cosmic rays is
consistent with the decay of GUT scale particles. The predicted mass is
m_X=10^b GeV, where b=14.6_{-1.7}^{+1.6}.Comment: 4 pages, 3 figures one figure removed, one table added, conclusions
essentially remained the same within errorbar
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