MORPHOLOGICAL STUDY OF DISTAL RADIOULNAR, RADIOCARPAL AND MEDIOCARPAL JOINTS ON CADAVER MATERIAL FROM ELDERLY PEOPLE. II. ARTICULAR CARTILAGINES AND DISCUS ARTICULARIS

Wrist joints are a complex system whose functioning depends on a number of factors. The most significant of them are the status/condition of discus articularis and the cartilages covering joint surfaces. This study on cadaver hands of elderly people (60 years old and over) covered the changes in joint cartilages and discus articularis and the role of these changes for the functional discomfort of wrist joints. The condition of the joints mentioned above has been observed with a magnifying glass (3x) in twelve cadaver hands. Material for light microscope observation was taken from  representative parts of discus articularis. The scopic investigation revealed erosions on the surface of the radiocarpal and mediocarpal joints cartilage. Such erosions were observed in two cases (16,67%) in radiocarpal joint and in 5 cases (41,67%) in mediocarpal joint. The microscopic observation showed indentations and fissures on the discus articularis surface, some of which filled with residual material. Some erosions have grown into fissures penetrating deeper. A decrease in the number of chondrocytes in discus articularis has been detected together with homogenization of extracellular matrix especially in their deeper layers. In the closest proximity with the cartilage surface, isogenous groups with a decreased number of chondrocytes were found out. Degenerative changes were established in chondrocytes, vacuoles being formed at the site of the dead chondrocytes. The extracellular halo substituted the fibrilated territorial matrix. A decreased cell number was observed in the overall structure of discus articularis. These changes in the structure of joint cartilage and discus articularis due to age are brought up for a discussion as a cause of possible functional discomfort in wrist joints often accompanied by a vague pain syndrome

Worker Reallocation Across Occupations in Western Germany

This paper analyzes the determinants of annual worker reallocation across disaggregated occupations in western Germany for the period 1985-2003. Employing data from the German Socio-Economic Panel, the pattern of average occupational mobility is documented. Worker reallocation is found to be strongly procyclical. Its determinants at the individual level are then investigated while controlling for unobserved worker heterogeneity. A dynamic probit fixed effects model is estimated to obtain coefficients and marginal effects. The incidental parameter bias is reduced by the method proposed in Hahn and Kuersteiner (2004). An interesting finding is that workers changing occupation are about 8 to 9 percent less inclined to experience occupational mobility in the subsequent year than workers who do not change. Except for workers with only compulsory education, the impact of age on the probability of occupational change is declining in the level of education. The unemployment rate has a negative effect on the probability of occupational changes, especially for female foreigners

Comparative Advantage and Risk Premia in Labor Markets

Using the Survey of Income and Program Participation (SIPP), we document a significant and positive association between earnings risk (both permanent and transitory) and the level of earnings across 21 industries. We propose an equilibrium framework to analyze the interplay between earnings volatility and the distribution of skills across workers in determining a relationship between earnings and risk. We use the model to decompose how much of the empirical correlation represents compensation for risk and how much represents selection. The positive association between permanent risk and earnings is compensation for risk, but selection is responsible for the observed relationship between temporary risk and the level of earnings

Job Mobility and Sorting: Theory and Evidence

I derive a measure of job mobility that reflects individuals ability to sort into the preferred jobs. Relying on the Survey of Income and Program Participation, I find that educational attainment tends to have a strong positive effect on internal (i.e., within firms) and external (i.e., between firms) job mobility. General experience and occupation-specific human capital have only a limited effect on both internal and external mobility. The impact of being versatile on an individual s external job mobility is substantial and similar in magnitude as the effect of a college degree on a high school dropout s external mobility

Die Methoden zur Einschätzung der Übertragbarkeit beruflicher Kompetenzen

This paper compares two estimation methods of occupational skills transferability, both theoretically and empirically. The first method is based on Shaw's (1984) study, and the second one is based on Ormiston's (2014) study. The main difference between these two methods is that Shaw's skills transferability is a 'market' approach. It is estimated based on an actual occupational change. On the other hand, Ormiston's skills transferability is a 'skills' approach estimated based on the knowledge, skills, and abilities (KSAs) shared across occupations. Although these two approaches produce very different estimates of occupational skills transferability, both estimates significantly explain the earnings losses of displaced workers. In particular, the displaced workers who find jobs in occupations more similar to their previous jobs, as measured by occupational skills transferability, on average, suffer smaller earnings losses than those who find less similar jobs

The Network Composition of Aggregate Unemployment

We develop a theory of unemployment in which workers search for jobs through a network of firms, the labor flow network (LFN). The lack of an edge between two companies indicates the impossibility of labor flows between them due to high frictions. In equilibrium, firms' hiring behavior correlates through the network, modulating labor flows and generating aggregate unemployment. This theory provides new micro-foundations for the aggregate matching function, the Beveridge curve, wage dispersion, and the employer-size premium. Using employer-employee matched records, we study the effect of the LFN topology through a new concept: `firm-specific unemployment'