205 research outputs found
Vitamin D supplementation does not improve human skeletal muscle contractile properties in insufficient young males
Vitamin D may be a regulator of skeletal muscle function, although human trials investigating this hypothesis are limited to predominantly elderly populations. We aimed to assess the effect of oral vitamin D3 in healthy young males upon skeletal muscle function
Payload characterization for CubeSat demonstration of MEMS deformable mirrors
Coronagraphic space telescopes require wavefront control systems for high-contrast imaging applications such as exoplanet direct imaging. High-actuator-count MEMS deformable mirrors (DM) are a key element of these wavefront control systems yet have not been flown in space long enough to characterize their on-orbit performance. The MEMS Deformable Mirror CubeSat Testbed is a conceptual nanosatellite demonstration of MEMS DM and wavefront sensing technology. The testbed platform is a 3U CubeSat bus. Of the 10 x 10 x 34.05 cm (3U) available volume, a 10 x 10 x 15 cm space is reserved for the optical payload. The main purpose of the payload is to characterize and calibrate the onorbit performance of a MEMS deformable mirror over an extended period of time (months). Its design incorporates both a Shack Hartmann wavefront sensor (internal laser illumination), and a focal plane sensor (used with an external aperture to image bright stars). We baseline a 32-actuator Boston Micromachines Mini deformable mirror for this mission, though the design is flexible and can be applied to mirrors from other vendors. We present the mission design and payload architecture and discuss experiment design, requirements, and performance simulations.United States. National Aeronautics and Space Administration (Space Technology Research Fellowship
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Hanford Site Groundwater Monitoring for Fiscal Year 2006
This report presents the results of groundwater monitoring for FY 2006 on DOE's Hanford Site. Results of groundwater remediation, vadose zone monitoring, and characterization are summarized. DOE monitors groundwater at the Hanford Site to fulfill a variety of state and federal regulations, including the Atomic Energy Act (AEA), the Resource Conservation and Recovery Act (RCRA), the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), and Washington Administrative Code (WAC)
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Summary of Hanford Site Groundwater Monitoring for Fiscal Year 2006
This booklet provides a summary of groundwater monitoring on the Hanford Site during FY 2006
Wavefront control in space with MEMS deformable mirrors for exoplanet direct imaging
To meet the high contrast requirement of 1×10[superscript −10] to image an Earth-like planet around a sun-like star, space telescopes equipped with coronagraphs require wavefront control systems. Deformable mirrors (DMs) are a key element of a wavefront control system, as they correct for imperfections, thermal distortions, and diffraction that would otherwise corrupt the wavefront and ruin the contrast. The goal of the CubeSat DM technology demonstration mission is to test the ability of a microelectromechanical system (MEMS) DM to perform wavefront control on-orbit on a nanosatellite platform. We consider two approaches for an MEMS DM technology demonstration payload that will fit within the mass, power, and volume constraints of a CubeSat: (1) a Michelson interferometer and (2) a Shack-Hartmann wavefront sensor. We clarify the constraints on the payload based on the resources required for supporting CubeSat subsystems drawn from subsystems that we have developed for a different CubeSat flight project. We discuss results from payload laboratory prototypes and their utility in defining mission requirements
Hanford Site Guidelines for Preparation and Presentation of Geologic Information
A complex geology lies beneath the Hanford Site of southeastern Washington State. Within this geology is a challenging large-scale environmental cleanup project. Geologic and contaminant transport information generated by several U.S. Department of Energy contractors must be documented in geologic graphics clearly, consistently, and accurately. These graphics must then be disseminated in formats readily acceptable by general graphics and document producing software applications. The guidelines presented in this document are intended to facilitate consistent, defensible, geologic graphics and digital data/graphics sharing among the various Hanford Site agencies and contractors
Cancer in World Trade Center responders: Findings from multiple cohorts and options for future study
Background
Three longitudinal studies of cancer incidence in varied populations of World Trade Center responders have been conducted.
Methods
We compared the design and results of the three studies.
Results
Separate analyses of these cohorts revealed excess cancer incidence in responders for all cancers combined and for cancers of the thyroid and prostate. Methodological dissimilarities included recruitment strategies, source of cohort members, demographic characteristics, overlap between cohorts, assessment of WTC and other occupational exposures and confounders, methods and duration of follow-up, approaches for statistical analysis, and latency analyses.
Conclusions
The presence of three cohorts strengthens the effort of identifying and quantifying the cancer risk; the heterogeneity in design might increase sensitivity to the identification of cancers potentially associated with exposure. The presence and magnitude of an increased cancer risk remains to be fully elucidated. Continued long-term follow up with minimal longitudinal dropout is crucial to achieve this goal
MEMS deformable mirror CubeSat testbed
To meet the high contrast requirement of 1 × 10[superscript −10] to image an Earth-like planet around a Sun-like star, space telescopes equipped with coronagraphs require wavefront control systems. Deformable mirrors are a key element of these systems that correct for optical imperfections, thermal distortions, and diffraction that would otherwise corrupt the wavefront and ruin the contrast. However, high-actuator-count MEMS deformable mirrors have yet to fly in space long enough to characterize their on-orbit performance and reduce risk by developing and operating their supporting systems. The goal of the MEMS Deformable Mirror CubeSat Testbed is to develop a CubeSat-scale demonstration of MEMS deformable mirror and wavefront sensing technology. In this paper, we consider two approaches for a MEMS deformable mirror technology demonstration payload that will fit within the mass, power, and volume constraints of a CubeSat: 1) a Michelson interferometer and 2) a Shack-Hartmann wavefront sensor. We clarify the constraints on the payload based on the resources required for supporting CubeSat subsystems drawn from subsystems that we have developed for a different CubeSat flight project. We discuss results from payload lab prototypes and their utility in defining mission requirements.United States. National Aeronautics and Space Administration (Office of the Chief Technologist NASA Space Technology Research Fellowship)Jeptha and Emily Wade FundMassachusetts Institute of Technology. Undergraduate Research Opportunities Progra
QCD
We discuss issues of QCD at the LHC including parton distributions, Monte
Carlo event generators, the available next-to-leading order calculations,
resummation, photon production, small x physics, double parton scattering, and
backgrounds to Higgs production.Comment: 115 pages, Latex, 47 figures, to appear in the Report of the ``1999
CERN Workshop on SM Physics (and more) at the LHC'', S. Catani, M. Dittmar,
D. Soper, W.J. Stirling, S. Tapprogge (convenors
Effectiveness of a training program for police officers who come into contact with people with mental health problems : A pragmatic randomised controlled trial
INTRODUCTION: Police officers frequently come into contact with individuals with mental health problems. Specialist training in this area for police officers may improve how they respond to individuals with mental health problems; however, evidence to support this is sparse. This study evaluated the effectiveness of one bespoke mental health training package for frontline police officers relative to routine training. DESIGN: Pragmatic, two-armed cluster randomised controlled trial in one police force in England. Police stations in North Yorkshire were randomised with frontline police officers receiving either a bespoke mental health training package or routine training. The primary outcome was the number of incidents which resulted in a police response reported to the North Yorkshire Police control room up to six months after delivery of training. Secondary outcomes included: likelihood of incidents using Section 136 of the Mental Health Act; likelihood of incidents having a mental health tag applied; and number of individuals with a mental health warning marker involved in incidents. The appropriateness of mental health tags applied to a random sample of incidents was checked by an independent mental health professional. Routinely collected data were used. RESULTS: Twelve police stations were recruited and randomised (Intervention group n = 6; Control group n = 6), and 249 officers received the bespoke mental health training intervention. At follow-up, a median of 397 incidents were assigned to trial stations in the intervention group, and 498 in the control group. There was no evidence of a difference in the number of incidents with a police response (adjusted incidence rate ratio (IRR) 0.92, 95% CI 0.61 to 1.38, p = 0.69), or in the number of people with mental health warning markers involved in incidents (adjusted IRR 1.39, 95% CI 0.91 to 2.10, p = 0.13) between the intervention and control groups up to six months following the intervention; however, incidents assigned to stations in the intervention group were more likely to have a mental health tag applied to them than incidents assigned to control stations (adjusted odds ratio 1.41, 95% CI 1.16 to 1.71, p = 0.001). The review of 100 incidents suggests that there may be incidents involving individuals with mental health issues that are not being recorded as such (Kappa coefficient 0.65). There was no statistically significant difference in the likelihood of Section 136 of the Mental Health Act being applied to an incident. CONCLUSIONS: The bespoke one day mental health training delivered to frontline officers by mental health professionals did not reduce the number of incidents reported to the police control room up to six months after its delivery; however training may have a positive effect on how the police record incidents involving individuals with mental health problems. Our trial has shown that conducting pragmatic trials within the police setting is feasible and acceptable. There is a wealth of routinely collected police data that can be utilised for research and further collaboration between police forces and academia is encouraged. TRIAL REGISTRATION: ISRCTN (ISRCTN11685602). The authors confirm that all ongoing and related trials for this drug/intervention are registered
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