Die Feminisierung der Lehrerschaft als Kohortenphänomen - Entwicklungen der Lehrerschaft an allgemein bildenden Schulen Baden-Württembergs

Der wachsende Frauenanteil in der Lehrerschaft wurde jüngst aus unterschiedlichen Gründen problematisiert und Maßnahmen vorgeschlagen, um diesem Trend entgegen zu wirken. Dabei wurde die Feminisierung zumindest implizit als historisches Phänomen aufgefasst. Hier wird ein sozialisationstheoretischer, kohortenspezifischer Ansatz vorgeschlagen und dessen Plausibilität mit Hilfe log-linearer Modelle nach dem A-P-C-Design geprüft. Diese machen andere praktische Konsequenzen plausibel als die bisher vorgeschlagenen. (DIPF/Orig.

Dynamics of suspensions of hydrodynamically structured particles: Analytic theory and experiment

We present an easy-to-use analytic toolbox for the calculation of short-time transport properties of concentrated suspensions of spherical colloidal particles with internal hydrodynamic structure, and direct interactions described by a hard-core or soft Hertz pair potential. The considered dynamic properties include self-diffusion and sedimentation coefficients, the wavenumber-dependent diffusion function determined in dynamic scattering experiments, and the high-frequency shear viscosity. The toolbox is based on the hydrodynamic radius model (HRM) wherein the internal particle structure is mapped on a hydrodynamic radius parameter for unchanged direct interactions, and on an existing simulation data base for solvent-permeable and spherical annulus particles. Useful scaling relations for the diffusion function and self-diffusion coefficient, known to be valid for hard-core interaction, are shown to apply also for soft pair potentials. We further discuss extensions of the toolbox to long-time transport properties including the low-shear zero-frequency viscosity and the long-time self-diffusion coefficient. The versatility of the toolbox is demonstrated by the analysis of a previous light scattering study of suspensions of non-ionic PNiPAM microgels [Eckert et al., J. Chem. Phys., 2008, 129, 124902] in which a detailed theoretical analysis of the dynamic data was left as an open task. By the comparison with Hertz potential based calculations, we show that the experimental data are consistently and accurately described using the Verlet-Weis corrected Percus-Yevick structure factor as input, and for a solvent penetration length equal to three percent of the excluded volume radius. This small solvent permeability of the microgel particles has a significant dynamic effect at larger concentrations.Comment: 25 pages, 24 figure

Entwicklung der Weiterbildungsbeteiligung in Deutschland

Zielsetzung des Projekts war es, Veränderungen der Weiterbildungsteilnahme und des Weiterbildungsverhaltens in Deutschland mit Hilfe multivariater Modelle zu theoriegeleitet zu beschreiben. Als Basis dienten Daten des Berichtssystems Weiterbildung, das seit 1979 in drei-jährigem Rhythmus erstellt wird. Im ersten Teil des Berichts stehen Analysen nach dem Alter-Periode-Kohorten Design im Vordergrund. Die Annahme, dass die Weiterbildungsteilnahme kohortenabhängig sei, impliziert, dass sich das Erleben zeitabhängiger gesellschaftlicher Entwicklungen in einem unterschiedlichen Lebensalter auf die Teilnahmebereitschaft an Weiterbildung auswirkt. Die Analysen erbrachten differenzierte Alters-, Perioden- und Kohorteneffekte für die Teilnahme an allgemeiner wie auch an beruflicher Weiterbildung. Weitere Indikatoren für die Weiterbildungsbereitschaft (Kursbelegungen, Teilnahmedauer) waren dagegen schwer zu analysieren, da die Daten hier zum Teil unvollständig waren bzw. schwer ineinander überführbar waren. Modernisierungseffekte, d.h. Effekte, die sich auf eine zunehmende gesellschaftliche Differenzierung zurückführen lassen, ließen sich in Bezug auf eine Weiterbildungsteilnahme nicht feststellen. Trotz massiver Datenrestriktionen wird in diesem Beitrag gezeigt, dass ein hohes Bildungsniveau in der Gruppe der darstellenden Künstler einen stark positiven Effekt auf das Einkommen aus erster Erwerbstätigkeit und auch auf das Gesamteinkommen ausübt. Für die Berufsgruppe der Musiker konnte ein positiver Effekt eines hohen Bildungsniveaus auf die Höhe des Gesamteinkommens ermittelt werden. Für die Generierung von Einkommen aus der zweiten Erwerbstätigkeit spielt das Bildungsniveau der darstellenden Künstler, aber auch der Musiker nur eine untergeordnete Rolle...Weiterbildung; Mikrozensus

Learning to reconstruct the bubble distribution with conductivity maps using Invertible Neural Networks and Error Diffusion

Electrolysis is crucial for eco-friendly hydrogen production, but gas bubbles generated during the process hinder reactions, reduce cell efficiency, and increase energy consumption. Additionally, these gas bubbles cause changes in the conductivity inside the cell, resulting in corresponding variations in the induced magnetic field around the cell. Therefore, measuring these gas bubble-induced magnetic field fluctuations using external magnetic sensors and solving the inverse problem of Biot-Savart Law allows for estimating the conductivity in the cell and, thus, bubble size and location. However, determining high-resolution conductivity maps from only a few induced magnetic field measurements is an ill-posed inverse problem. To overcome this, we exploit Invertible Neural Networks (INNs) to reconstruct the conductivity field. Our qualitative results and quantitative evaluation using random error diffusion show that INN achieves far superior performance compared to Tikhonov regularization.Comment: Accepted for Oral presentation at WCIPT11 (11th World Congress on Industrial Process Tomography

The roles of wedging and friction in the mechanics of dental occlusal contacts

Objective: The primary aim of this project is to elucidate the basic mechanical engineering principles that govern and explain unexpected and counter-intuitive occlusal contact force measurements. Methods: Forces were measured on matched pairs of first molar denture, ceramic and stainless steel crowns during occlusion and disclusion, with human saliva and dry (control). The weighted maxillary assembly, guided by a precision slide, was lowered onto, and raised from, the mandibular crown. The forces experienced by the mandibular tooth were continuously measured by the load cell that supported it. Statistical analyses included LOESS smoothing splines and generalized additive models. Principles of basic statics and classic friction were applied to explain and validate the results. Results: It was determined that within the span of a single chomp, the in-occlusal plane force component (Flateral) on the tooth is highly variable in direction and/or magnitude. The most salient observations were that Flateral was higher in disclusion than in occlusion, and the largest Flateral did not necessarily occur when the bite force was maximum. Furthermore, saliva significantly affected the results. Conclusions: The results demonstrated that contacting teeth experience complex transient mechanical environments that can be readily explained with elementary engineering principles involving wedging and friction at the occlusal contacts

Prognostic significance of DNA cytometry in cutaneous malignant lymphomas.

The current classification of cutaneous malignant lymphomas (ML) into low-grade and high-grade lymphomas was found to be of limited reproducibility and permitted only a rough prediction about outcome. With this in mind, the relationship between nuclear DNA content and both prognosis and histologic grading according to the Kiel classification was evaluated on Feulgen-stained imprint specimens. In all, 49 cases of malignant non-Hodgkin's lymphoma, primary of the skin or with an involvement of the skin as one of the first symptoms, were studied using a computerized high-resolution image analysis system. The 2c deviation index (2cDI), which reflects the variation of the nuclear DNA values around the normal diploid peak, was found to be the best prognostically relevant criterion. Using the 2cDI, a significant discrimination (P less than 0.001 in the U test) between low-grade and high-grade ML was achieved. The prognostic benefit of the 2cDI was well documented by a significant inverse correlation between the 2cDI and the period of time until the patients progressed at least into one higher stage or died of lymphoma (r equals -0.63, P less than 0.05). In addition, the 2cDI enabled prognosis of the course of disease. In the group with low 2cDI values (2cDI, less than 0.5), no progression of the disease was observed after 1 year. In the groups presenting with a 2cDI between 0.5 and 1.0 and higher than 1.0, a progression was found in 57% and 64% of the cases studied, respectively. In conclusion, these measurements indicate that the determination of DNA distribution patterns in imprint specimens allows a precise and objective prognostic evaluation of cutaneous ML