Search Results

You are looking at 1 - 10 of 33 items

  • Author: Stephan Walter x
Clear All Modify Search
Festschrift für Helmut Brackert zum 65. Geburtstag

Abstract

This study was designed to test the hypothesis that impaired neutrophil function might contribute to the development of bacterial pneumonia in patients with HIV-infection. Numbers of inflammatory cells and immunoglobulin G Fcγ receptor (IgG FcγR) I, II, III levels were investigated in bronchoalveolar lavage (BAL) fluid of HIV-seronegative and HIV-infected patients with bacterial pneumonia. The 99 patients were classified into three groups: I: HIV-seronegative and pneumonia (n=40); II: HIV-infected and pneumonia (n=19); III: HIV-seronegative with other pulmonary diseases than pneumonia (n=40). The results of groups I and II, II and III, and I and III were compared. The percentage of alveolar macrophages was significantly lower (group II vs. III: p=0.005, group I vs. III: p=0.001), that of neutrophils increased significantly in patients with pneumonia (group II vs. III: p=0.02, group I vs. III: p=0.01). Lymphocytes differed only between groups I and III (p=0.04). Although only the expression of FcγRI was significantly higher in HIV-seronegative pneumonia patients compared to those without pneumonia (p=0.01), the mean expression of all three receptors was lower in the HIV-infected group, with that of FcγRI approaching statistical significance.

This report provides first evidence that altered FcγR expression on BAL neutrophils might contribute to the increased susceptibility of HIV-infected patients to bacterial pneumonia.

Abstract

The heat capacity of synthetic eskolaite, Cr2O3, and of the synthetic spinels magnesiochromite, MgCr2O4, and chromite, FeCr2O4 were measured from 1.5 K to 340 K. For MgCr2O4, a substantial magnetic contribution to the entropy is revealed by a sharp peak in the heat capacity curve at 12.55 ± 0.05 K, which indicates the transition to antiferromagnetic long-range order. Integration of the heat capacity curve yields a value of 118.3 ± 1.2 J/(mol·K) for the standard entropy at 298.15 K, which is in excellent agreement with that calculated from phase equilibria studies on the reaction MgCr2O4+ SiO2 = Cr2O3 + MgSiO3. The new calorimetric results for Cr2O3 indicate a standard entropy at 298.15 K of 82.8 ± 0.8 J/(mol·K). The measurements for FeCr2O4 show three distinct heat capacity anomalies, one of which (peaking at 36.5 ± 0.2 K) was missed by previous low temperature heat capacity measurements, which only extend down to 53 K. Integration of the heat capacity curve yields a value for the standard entropy at 298.15 K of 152.2 ± 3.0 J/(mol·K) for FeCrO4, some 6 J/ (mol·K) greater than the previous calorimetric value.

These low-temperature heat capacity data were combined with high-temperature heat content measurements from the literature to derive heat capacity equations for all three phases to 1800 K. The resulting heat capacity equations were then used to extract revised recommended values of the standard enthalpies of formation and entropies of MgCr2O4 and Cr2O3 from phase equilibrium data. For FeCr2O4, the phase equilibrium data are of dubious accuracy, the enthalpy of formation is only approximate

Abstract

The 2005 reform of the German welfare system introduced two competing organizational models for welfare administration. In most districts, a centralized organization was established where local welfare agencies are bound to central directives. At the same time, 69 districts were allowed to opt for a decentralized organization. We evaluate the relative success of both types in terms of integrating welfare recipients into employment. Compared to centralized organization, decentralized organization has a negative effect on employment chances of males. For women, no significant effect is found. These findings are robust to the inclusion of aspects of internal organization common to both types of agencies.