Industry Structure and Productivity Growth: Panel Data Evidence for Germany from 19712000

The paper presents a detailed industry-level productivity analysis (52 industries) for the effects of industry structure on TFP growth for Germany from 1971 until 2000. The analysis builds on a theory by Acemoglu et al. (2003) relating industry structure and productivity growth of an industry. The analysis reveals positive effects of vertically disintegrated industries with respect to TFP growth during a convergence period. After the convergence period, there remains only a positive effect for industries which use a higher share of imported intermediate inputs, especially in manufacturing industries, providing evidence for beneficial effects of higher levels of international cooperation on TFP growth. The database of the analysis is the recently collected productivity database for Germany. The Ifo Productivity Database, which is unique due to its high data quality, offers industry- and asset-specific capital data and also for the first time data on domestic and international intermediates input over such a long period. The database allows to allocate productivity growth according to the gross output growth accounting method following Jorgenson and Stiroh (2000)

Computers and Student Learning:Bivariate and Multivariate Evidence on the Availability and Use of Computers at Home and at School

We estimate the relationship between computers and students’ educational achievement in the international student-level PISA database. Bivariate analyses show a positive correlation between achievement and computer availability both at home and at school. However, once we control extensively for family background and school characteristics, the relationship gets negative for home computers and insignificant for school computers. Thus, mere availability of computers at home seems to distract students from effective learning. But achievement shows a positive conditional relationship with computer use for education and communication at home and an inverted U-shaped relationship with computer and internet use at school.Computers at home, computers at school, student achievement, educational production, PISA.

Probability densities of a forced probe particle in glass: results from mode coupling theory and simulations of active microrheology

We investigate the displacements of a probe particle inside a glass, when a strong external force is applied to the probe (active nonlinear microrheology). Calculations within mode coupling theory are presented for glasses of hard spheres and compared to Langevin and Brownian dynamics simulations. Under not too strong forces where the probe remains trapped, the probe density distribution becomes anisotropic. It is shifted towards the direction of the force, develops an enhanced tail in that direction (signalled by a positive skewness), and exhibits different variances along and perpendicular to the force direction. A simple model of an harmonically trapped probe rationalizes the low force limit, with strong strain softening setting in at forces of the order of a few thermal energies per particle radius

Capital Market Institutions and Venture Capital: Do They Affect Unemployment and Labour Demand?

This paper analyses the influence of the capital market on the labour market. Especially the impact of start-up financing on the structure of unemployment is of interest. We use a cross-country panel data analysis to examine how venture capital investment influences disaggre-gate unemployment. As we expected, venture capital investment has different influences on sectoral-, educational- and occupational-specific unemployment. We suggest, on the basis of the regression results that venture capital investment is a catalyst of structural change and has contributed to the faster growing internet and new economy sector in countries like the U.S. that have a well-developed venture capital market.Labor markets, venture capital, employment, new economy, panel analysis

Computers and Student Learning: Bivariate and Multivariate Evidence on the Availability and Use of Computers at Home and at School

We estimate the relationship between students’ educational achievement and the availability and use of computers at home and at school in the international student-level PISA database. Bivariate analyses show a positive correlation between student achievement and the availability of computers both at home and at schools. However, once we control extensively for family background and school characteristics, the relationship gets negative for home computers and insignificant for school computers. Thus, the mere availability of computers at home seems to distract students from effective learning. But measures of computer use for education and communication at home show a positive conditional relationship with student achievement. The conditional relationship between student achievement and computer and internet use at school has an inverted U-shape, which may reflect either ability bias combined with negative effects of computerized instruction or a low optimal level of computerized instruction.computers at home, computers at school, student achievement, educational production, PISA, education

On the Bauschinger effect in supercoooled melts under shear: results from mode coupling theory and molecular dynamics simulations

We study the nonlinear rheology of a glass-forming binary mixture under the reversal of shear flow using molecular dynamics simulations and a schematic model of the mode-coupling theory of the glass transition (MCT). Memory effects lead to a history-dependent response, as exemplified by the vanishing of a stress-overshoot phenomenon in the stress--strain curves of the sheared liquid, and a change in the apparent elastic coefficients around states with zero stress. We investigate the various retarded contributions to the stress response at a given time schematically within MCT. The connection of this macroscopic response to single-particle motion is demonstrated using molecular-dynamics simulation

Effects of compost and digestate on environment and plant production – results of two research projects

A yearly amount of 9.3x106t compost and digestate derived from separately collected organic waste is produced in the 25 European Union member states. The improvement of soil properties is a major benefit of compost application. However, little is known about the occurrence of organic pollutants in compost. In order to estimate the potential of Swiss composts and digestates to influence soil fertility and plant health, one hundred products representative for the different composting systems and qualities available on the Swiss market were analyzed in two research projects. In the first study, polycyclic aromatic hydrocarbons (PAHs), ortho substituted and dioxin-like polychlorinated biphenyls (PCBs, DL PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), tetrabromobisphenol A (TBBPA), perfluorinated alkyl substances (PFAS), pesticides, chlorinated paraffins (CPs), phthalates and nonylphenol (NP) were analyzed. All compound classes were detected except for NP. PFAS, HBCD, TBBPA, some compounds out of PBDEs and pesticides were found in compost and digestate for the first time. Concentrations of most compounds were in the low ppb range. Contents of PAHs were between 600 and 12473 μg/kg dry weight (dw) and contents of HBCD and CPs between 17 and 384 μg/kg dw. Tests with springtails (Folsomia candida) have been shown to be a versatile tool for ecotoxicological assessment. Within these tests, inhibiting and stimulating effects due to compost application were observed. Except for high PAHs contents, no major problem with regard to contamination of compost and digestate was identified. In the second study, the physical, chemical and biological properties of the composts and digestats, and their influence on soil fertility and plant growth, were characterized. The organic substance and the nutrient content of the composts varied largely between the composts with the feedstock materials as major influencing factors. The respiration rate and enzyme activities exhibited large variations as well, particularly in the youngest composts. These differences decreased when the composts became more mature. Maturity, the degradation stage of the organic matter, depended not only on the age of the compost, but also on the management of the process. The N-mineralization potential of compost added to soil showed that a high proportion of young composts immobilized the nitrogen in the soil. Two compost parameters allowed to predict the risk of nitrogen immobilization in soil: the NO3- and the humic acids contents. The phytotoxicity of the composts varied largely even in mature composts, showing that the storage of the compost plays a decisive role. While the majority of composts protected cucumber plants against Pythium ultimum, only a few composts suppressed Rhizoctonia solani in basil. With respect to disease suppression, the management of the maturation process seems to play a major role. In field experiments, some biologically immature composts immobilized nitrogen in soil and reduced growth of maize. With additional fertilization, however, it was possible to compensate this effect. Digestates and composts increased the pH-value and the biological activity of soil. These effects were observable also one maize season after compost application. In conclusion, the management of the composting process seems to influence the biological quality of the composts and digestats to a higher extent than the feedstock materials or the composting system. More attention should be paid to this biological quality, in order to produce composts with more beneficial effects on crops

Families, schools, and primary-school learning : evidence for Argentina and Colombia in an international perspective

This paper estimates the relationshipbetween family background, school characteristics, and student achievement in primary school in two Latin American countries, Argentina and Colombia, as well as several comparison countries. The database used is the student-level international achievement data of the Progress in International Reading Literacy Study (PIRLS), which tested the reading performance of fourth-grade students in 2001. The nationally representative samples have 3,300 students in Argentina and 5,131 students in Colombia. The emerging general pattern of results is that educational performance is strongly related to students'family background, weakly to some institutional school features, and hardly to schools'resource endowments. In an international perspective, estimated family background effects are relatively large in Argentina, and relatively small in Colombia. A specific Argentine feature is the lack of performance differences between rural and urban areas. A specific Colombian feature is the lack of significant differences between gender performance. Nonnative students and students not speaking Spanish at home have particularly weak performance in both countries. But there are no differences by parental occupation and no positive effects of kindergarten attendance. In Argentina, students perform better in schools with a centralized curriculum and ability-based class formation.Teaching and Learning,Primary Education,Educational Sciences,Health Monitoring&Evaluation,Gender and Education