We present a straightforward method for particle identification and background rejection in 3He proportional counters for use in neutron detection. By measuring the risetime and pulse height of the ...preamplifier signals, one may define a region in the risetime versus pulse height space where the events are predominately from neutron interactions. For six proportional counters surveyed in a low-background environment, we demonstrate the ability to reject alpha-particle events with an efficiency of 99%. By applying the same method, we also show an effective rejection of microdischarge noise events that, when passed through a shaping amplifier, are indistinguishable from physical events in the counters. The primary application of this method is in measurements where the signal-to-background for counting neutrons is very low, such as in underground laboratories.
We present results for detection of X-rays by large area avalanche photodiodes (APDs) in strong magnetic fields and at cryogenic temperatures. Whereas at room temperature we observe essentially no ...effects on the response, at cryogenic temperature we observe significant distortion when the magnetic field is in the plane of the APD surface (and thus perpendicular to the electric field in the APD). At all temperatures, effects are minor when the magnetic field is normal to the APD surface (and thus parallel to the electric field in the APD). We performed measurements of the response of an APD to illumination by X-rays in fields between 0 and 4.6
T, for temperatures between 77 and 250
K. Measurements were performed using
241Am and
55Fe sources, and 1.5
keV X-rays produced by aluminum fluorescence. The data indicate that the effects are associated with those X-rays that are absorbed in the drift region of the APD.
Hypoglycemic episodes are negative sequelae of inadequate treatment of diabetes. Many of them lead to hospitalization.
Between 8/2003 und 9/2007 110 consecutive patients who had been admitted because ...of hypoglycemia to a tertiary hospital were analyzed. The underlying causes of hypoglycemia and associated individual psychosocial factors were assessed. Hypoglycemia was diagnosed when glucose at admittance was < 2.8 mmol/l (50 mg/dl) with or < 2.2 mmol/l (40 mg/dl) without symptoms.
76 patients were women and 99 patients suffered from type 2 diabetes. The mean age was 77.8 ± 9.4 years. The HbA1c of the patients with type 2 diabetes at admission was 6.5 ± 1.5 %. The greatest number of hypoglycemia episodes were associated with sulfonylurea and analoga (25), insulin (67), and the combination insulin and sulfonylurea (17). The applied sulfonylureas were in 38 % glibenclamide, in 55 % glimepiride and in 7 % repaglinide. The mean in-hospital stay was 10.4 days after admittance for hypoglycemia, the mean stay was 8.4 days for patients without hypoglycemia. Concerning creatinine there was a normal kidney function in 37.6 % of the patients, the calculated creatinine clearance was normal in only about 15 % of the patients. In 13 patients (12 %) any antidiabetic medication was stopped at time of discharge. 20 patients, chosen randomly, were analyzed concerning the costs associated with the hospital admittance. The mean age of these patients was 76.8 years and their mean stay in hospital was 10.2 day. The costs covered 3,158 €. The mean costs for the other internal patients was 2,716 €.
Patient adapted treatment of diabetes is of importance for prevention of hypoglycemia especially in the elderly. The costs resulting from hospitalization and the complications linked to hypoglycemia can be largely prevented.
An extensive study of GeV light-ion-induced multifragmentation and its possible interpretation in terms of a nuclear liquid–gas phase transition has been performed with the Indiana Silicon Sphere ...(ISiS)
4
π
detector array. Measurements were performed with 5–15
GeV/
c
p
,
p
¯
, and
π
-
beams incident on
197Au and 2–5
GeV
3He incident on
natAg and
197Au targets. Both the reaction dynamics and the subsequent decay of the heavy residues have been explored. The data provide evidence for a dramatic change in the reaction observables near an excitation energy of
E
*
/
A
=
4
–
5
MeV
/
residue
nucleon
. In this region, fragment multiplicities and energy spectra indicate emission from an expanded/dilute source on a very short time scale (20–50
fm/
c). These properties, along with caloric curve and scaling-law behavior, yield a pattern that is consistent with a nuclear liquid–gas phase transition.
The parity-violating (PV) asymmetry of inclusive π- production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 ...experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasifree photoproduction off the neutron via the Δ0 resonance. In the context of heavy-baryon chiral perturbation theory, this asymmetry is related to a low-energy constant d(Δ)- that characterizes the parity-violating γNΔ coupling. Zhu et al. calculated d(Δ)- in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from A(γ)-=-5.2 to +5.2 ppm. The measurement performed in this work leads to A(γ)-=-0.36±1.06±0.37±0.03 ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to V(ud)/V(us). The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the N-Δ axial transition form factors using PV electron scattering.
Weather Research and Forecasting (WRF) single-column model simulations were performed in the late summer of 2012 in order to analyse the diurnal changes of the planetary boundary layer (PBL). Five ...PBL schemes were tested with the WRF. From the radiometer and wind-profiler measurements at one station, derived PBL heights were also compared to the simulations. The weather conditions during the measurement period proved to be dry; the soil moisture was below wilting point 85 percent of the time. Results show that (1) simulation-based PBL heights are overestimated by about 500-1000 m with respect to the observation-based PBL heights, and (2) PBL height deviations between different observation-based methods (around 700 m in the midday) are comparable with PBL height deviations between different model schemes used in the WRF single-column model. The causes of the deviations are also discussed. It is shown that in the estimation of the PBL height the relevance of the atmospheric profiles could be as important as the relevance of the estimation principles.
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