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The time dependence of the relative light emission of Eljen Technology EJ-200 polyvinyltoluene-based plastic scintillator was measured between 1 and 10 μ s after the passage of a particle shower, a singly charged particle (atmospheric muon), and with a UV LED exciting the fluor. This was compared in magnitude to the integrated response for the prompt light (within 500 ns of excitation). A model with a time-dependent yield consisting of three exponentially decaying components (fast, medium, and slow) was developed to fit the data. Note that the exact time structure of early (< 1 μ s) light emission was not measured for individual components, only for all three components together This model assumes all three components share the same rise time. The decay time constants of the fast, medium and slow components are, respectively, 7.8 ns, 490 ns, and 2370 ns. The relative total normalized yields for each component are: fast 95.8%, medium 2.2%, and slow 2.0%. [ABSTRACT FROM AUTHOR]

The HELIX cosmic-ray detector is a balloon-borne instrument designed to measure the flux of light isotopes in the energy range from 0.2 GeV/n to beyond 3 GeV/n. It will rely on a ring-imaging Cherenkov (RICH) detector for particle identification at energies greater than 1 GeV/n and will use aerogel tiles with refractive index near 1.15 as the radiator. To achieve the performance goals of the experiment it is necessary to know the refractive index and its position dependence over the lateral extent of the tiles to a precision of O(1 0 − 4 ). In this paper we describe the apparatus and methods developed to calibrate the HELIX tiles in an electron beam, in order to meet this requirement. [ABSTRACT FROM AUTHOR]

Innovative and coordinated strategies to address weight bias among health professionals are urgently needed. We conducted a systematic literature review of empirical peer-reviewed published studies to assess the impact of interventions designed to reduce weight bias in students or professionals in a health-related field. Combination sets of keywords based on three themes (1: weight bias/stigma; 2: obesity/overweight; 3: health professional) were searched within nine databases. Our search yielded 1447 individual records, of which 17 intervention studies satisfied the inclusion criteria. Most studies ( n = 15) included medical, dietetic, health promotion, psychology and kinesiology students, while the minority included practicing health professionals ( n = 2). Studies utilized various bias-reduction strategies. Many studies had methodological weaknesses, including short assessment periods, lack of randomization, lack of control group and small sample sizes. Although many studies reported changes in health professionals' beliefs and knowledge about obesity aetiology, evidence of effectiveness is poor, and long-term effects of intervention strategies on weight bias reduction remain unknown. The findings highlight the lack of experimental research to reduce weight bias among health professionals. Although changes in practice will likely require multiple strategies in various sectors, well-designed trials are needed to test the impact of interventions to decrease weight bias in healthcare settings. [ABSTRACT FROM AUTHOR]

The cosmic-ray energetics and mass (CREAM) investigation is designed to measure cosmic-ray composition to the supernova energy scale of 1015 eV in a series of ultra long duration balloon (ULDB) flights. The first flight is planned to be launched from Antarctica in December 2004. The goal is to observe cosmic-ray spectral features and/or abundance changes that might signify a limit to supernova acceleration. The particle charge (Z) measurements will be made with a timing-based charge detector and a pixelated silicon charge detector to minimize the effect of backscatter from the calorimeter. The particle energy measurements will be made with a transition radiation detector (TRD) for Z>3 and a sampling tungsten/scintillator calorimeter for Z⩾1 particles, allowing inflight cross calibration of the two detectors. The status of the payload construction and flight preparation are reported in this paper. [Copyright &y& Elsevier]

We present the design of a four-photomultiplier tube (PMT) assembly for measuring light generation in the Boronated Scintillator Detector (BSD) of the Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM). The light produced in the scintillator includes a contribution from the capture of thermalized neutrons produced in cosmic ray interactions, as well as delayed fluorescence, in the range of several microseconds following the incident cosmic ray impact. The BSD is held in an insensitive state until a cosmic-ray trigger causes a rapid turn on of the PMTs to detect late light signals, several microseconds after the trigger. The design includes two pulsed high-voltage supplies, which serve to gate the first two dynodes of the Hamamatsu R1924A PMTs used in the assembly. When the dynode gates are held in the "off" state, this scheme is shown to suppress >105 photons from injection into the tube's multiplier stage, while being capable of rapid switching into a stable operating mode in less than 1 μ s. This mitigates any backgrounds from afterpulsing that might otherwise be present in the PMT response following the cosmic ray incidence. [ABSTRACT FROM AUTHOR]