201 research outputs found
Estimating the Demand for Health Care with Panel Data: A Semiparametric Bayesian Approach
This paper is concerned with the problem of estimating the demand for health care with panel data. A random effects model is specifed in a semiparametric Bayesian fashion using a Dirichlet process prior. This results in a very exible mixture distribution with an in nite number of
components for the random effects. Therefore, the model can be seen as a natural extension of prevailing latent class models. A full Bayesian analysis using Markov chain Monte Carlo (MCMC)simulation methods is discussed. The methodology is illustrated with an application using data from Germany
Heavy Meson Production at COSY - 11
The COSY-11 collaboration has measured the total cross section for the pp -->
pp eta-prime and pp --> pp eta reactions in the excess energy range from
Q = 1.5 MeV to Q = 23.6 MeV and from Q = 0.5 MeV to Q = 5.4 MeV,
respectively.
Measurements have been performed with the total luminosity of 73 nb^(-1) for
the pp --> pp eta reaction and 1360 nb^(-1) for the pp --> pp eta-prime one.
Recent results are presented and discussed.Comment: Invited talk at 4th International Conference on Physics at Storage
Rings (STORI 99), Bloomington, Indiana, USA, September 12-16, 199
Near-Threshold eta Meson Production in Proton-Proton Collisions
The production of eta mesons has been measured in the proton-proton
interaction close to the reaction threshold using the COSY-11 internal facility
at the cooler synchrotron COSY. Total cross sections were determined for eight
different excess energies in the range from 0.5 MeV to 5.4 MeV. The energy
dependence of the total cross section is well described by the available
phase-space volume weighted by FSI factors for the proton-proton and proton-eta
pairs.Comment: 9 pages, 1 table, 5 figure
Saturation of the filament density of ultrashort intense laser pulses in air
We experimentally and numerically characterize multiple filamentation of laser pulses with incident intensities of a few TW/cm2. Propagating 100TW laser pulses over 42m in air, we observe a new propagation regime where the filament density saturates. As also evidenced by numerical simulations in the same intensity range, the total number of filaments is governed by geometric constraints and mutual interactions among filaments rather than by the available power in the bea
“Alle wahren Gefühle verbergen und mit fester Stimme und wohlformulierten Sätzen glänzen!” - Die Bedeutung von Selbstdarstellungsregeln im Bewerbungsinterview
Total Cross Section of the Reaction pp \to pK^+\Lambda Close to Threshold
The energy dependence of the total cross section for the pp \to pK^+\Lambda
reaction was measured in the threshold region covering the excess energy range
up to 7MeV.
Existing model calculations describe the slope of the measured cross sections
well, but are too low by a factor of two to three in rate.
The data were used for a precise determination of the beam momentum of the
COSY-synchrotron.Comment: 11 pages, 5 figure
Resting and Post Bronchial Challenge Testing Carbon Dioxide Partial Pressure in Individuals with and without Asthma
Objective: There is conflicting evidence about resting carbon dioxide levels in asthmatic individuals. We wanted to determine if transcutaneously measured carbon dioxide levels prior and during bronchial provocation testing differ according to asthma status reflecting dysfunctional breathing. Methods: We investigated active firefighters and policemen by means of a validated questionnaire on respiratory symptoms, spirometry, bronchial challenge testing with methacholine (MCT) and measurement of transcutaneous blood carbon dioxide partial pressure (PtcCO 2) at rest prior performing spirometry, one minute and five minutes after termination of MCT. A respiratory physician blinded to the PtcCO2 results assigned a diagnosis of asthma after reviewing the available study data and the files of the workers medical screening program. Results: The study sample consisted of 128 male and 10 female individuals. Fifteen individuals (11%) had physiciandiagnosed asthma. There was no clinically important difference in median PtcCO 2 at rest, one and five minutes after recovery from MCT in asthmatics compared to non-asthmatics (35.6 vs 35.7 mmHg, p = 0.466; 34.7 vs 33.4 mmHg, p = 0.245 and 37.4 vs 36.4 mmHg, p = 0.732). The median drop in PtcCO2 during MCT and the increase after MCT was lower in asthmatics compared to non-asthmatics (0.1 vs 3.2 mmHg, p = 0.014 and 1.9 vs 2.9 mmHg, p = 0.025). Conclusions: PtcCO2 levels at rest prior and during recovery after MCT do not differ in individuals with or without physicia
Effect of gender difference on platelet reactivity
Background Previous studies have suggested that women do not accrue equal therapeutic benefit from antiplatelet medication as compared with men. The physiological mechanism and clinical implications behind this gender disparity have yet to be established. Methods On-treatment platelet reactivity was determined in 717 men and 234 women on dual antiplatelet therapy, undergoing elective coronary stent implantation. Platelet function testing was performed using arachidonic acid and adenosine diphosphate-induced light transmittance aggregometry (LTA) and the VerifyNow P2Y12 and Aspirin assays. Also the incidence of all-cause death, non-fatal acute myocardial infarction, stent thrombosis and ischaemic stroke was evaluated. Results Women had higher baseline platelet counts than men. Women exhibited a higher magnitude of on-aspirin platelet reactivity using LTA, but not using the VerifyNow Aspirin assay. The magnitude of on-clopidogrel platelet reactivity was significantly higher in women as compared with men with both tests used. The cut-off value to identify patients at risk as well as the incidence of clinical endpoints was similar between women and men (16/234[6.8%] vs. 62/717[8.6%], p=0.38). Conclusion Although the magnitude of platelet reactivity was higher in women, the absolute difference between genders was small and both the cut-off value to identify patients at risk and the incidence of the composite endpoint were similar between genders. Thus, it is unlikely that the difference in platelet reactivity accounts for a worse prognosis in women
- …