Sovereign bond risk premiums

Credit risk has become an important factor driving government bond returns. We therefore introduce an asset pricing model which exploits information contained in both forward interest rates and forward CDS spreads. Our empirical analysis covers euro-zone countries with German government bonds as credit risk-free assets. We construct a market factor from the first three principal components of the German forward curve as well as a common and a country-specific credit factor from the principal components of the forward CDS curves. We find that predictability of risk premiums of sovereign euro-zone bonds improves substantially if the market factor is augmented by a common and an orthogonal country-specific credit factor. While the common credit factor is significant for most countries in the sample, the country-specific factor is significant mainly for peripheral euro-zone countries. Finally, we find that during the current crisis period, market and credit risk premiums of government bonds are negative over long subintervals, a finding that we attribute to the presence of financial repression in euro-zone countries

IPOs and product quality

Given recent public attention paid to high-flying Internet IPOs such as Yahoo and Amazon.com, we explore a product market motive for going public. We develop a model where consumers discern product quality from the stock price. The model predicts that only better-quality firms will go public. Effects of IPO announcements on rival firms' stock prices are related to inferences about market size and market share. The model also predicts that the likelihood of "hot issue" markets depends on the distribution of market size uncertainty and the degree of network externalities present in consumer preferences.published_or_final_versio

Methylation Status of Imprinted Genes and Repetitive Elements in Sperm DNA from Infertile Males

Stochastic, environmentally and/or genetically induced disturbances in the genome-wide epigenetic reprogramming processes during male germ-cell development may contribute to male infertility. To test this hypothesis, we have studied the methylation levels of 2 paternally (H19 and GTL2) and 5 maternally methylated (LIT1, MEST, NESPAS, PEG3, and SNRPN) imprinted genes, as well as of ALU and LINE1 repetitive elements in 141 sperm samples, which were used for assisted reproductive technologies (ART), including 106 couples with strictly male-factor or combined male and female infertility and 28 couples with strictly female-factor infertility. Aberrant methylation imprints showed a significant association with abnormal semen parameters, but did not seem to influence ART outcome. Repeat methylation also differed significantly between sperm samples from infertile and presumably fertile males. However, in contrast to imprinted genes, ALU methylation had a significant impact on pregnancy and live-birth rate in couples with male-factor or combined infertility. ALU methylation was significantly high-er in sperm samples leading to pregnancy and live-birth than in those that did not. Sperm samples leading to abortions showed significantly lower ALU methylation levels than those leading to the birth of a baby. Copyright (C) 2011 S. Karger AG, Base

How residual stresses affect the fracture properties of layered thin films

The continued miniaturization effort has revealed exciting new material behavior at small length scales, where pronounced size effects come into play and material properties are subject to change. This has led to the development of miniaturized testing techniques to determine local plastic properties. So far, however, only few efforts regarding the determination of residual stresses and fracture properties in miniaturized systems were made. In this presentation, we will focus on recent developments regarding the measurement of residual stresses and miniaturized fracture properties using FIB based sample preparation and in situ SEM experiments. The depth resolved residual film stresses are determined by an improved stepwise beam layer removal method [1]. From the same film systems, beams are FIB fabricated for miniaturized fracture testing in the SEM [2]. We will discuss the general possibilities, challenges, and benefits of these approaches by examining the internal stresses and fracture properties of single layer and multilayer thin films in the immiscible system Cu-W. Particular emphasis is placed on the effect of residual stresses on the fracture properties. Moreover, possible limitations of commonly used data analysis approaches are addressed, and related improvements using finite element modelling to determine crack-driving forces in the presence of interfaces and residual stresses are presented [3]. Notably, the required material input data in terms of flow behavior for this modeling approach was determined using spherical nanoindentation experiments on single and multilayer films. Finally, the possibility of further miniaturization of such experiments by using in situ TEM is demonstrated [4]

Inbreeding, Microsatellite Heterozygosity, and Morphological Traits in Lipizzan Horses

While the negative effects of inbreeding and reduced heterozygosity on fecundity and survival are well established, only a few investigations have been carried out concerning their influence on morphological traits. This topic is of particular interest for a small and closed population such as the Lipizzan horse. Thus, 27 morphological traits were measured in 360 Lipizzan mares and were regressed on the individual inbreeding coefficients, as well as on the individual heterozygosity and mean squared distances (mean d2) between microsatellite alleles within an individual. Both individual heterozygosity and mean d2 were based on 17 microsatellite loci dispersed over 14 chromosomes. The results obtained by multivariate analysis reveal significant effects of stud (P <.0001), age at measurement (P <.0001), and mean d2 (P =.0143). In univariate analyses, significant associations were obtained between length of pastern-hindlimbs and inbreeding coefficient (P <.01), length of cannons-hindlimb and mean d2 (P <.01), and length of neck and mean d2 (P <.001). After adjustment of single-test P values for multiple tests (Hochberg's step-up Bonferroni method), only the association of the length of neck and mean d2 remained significant (P =.0213). Thus, no overall large effects of inbreeding, microsatellite heterozygosity, and mean d2 on morphological traits were observed in the Lipizzan hors

Inbreeding, Microsatellite Heterozygosity, and Morphological Traits in Lipizzan Horses

While the negative effects of inbreeding and reduced heterozygosity on fecundity and survival are well established, only a few investigations have been carried out concerning their influence on morphological traits. This topic is of particular interest for a small and closed population such as the Lipizzan horse. Thus, 27 morphological traits were measured in 360 Lipizzan mares and were regressed on the individual inbreeding coefficients, as well as on the individual heterozygosity and mean squared distances (mean d2) between microsatellite alleles within an individual. Both individual heterozygosity and mean d2 were based on 17 microsatellite loci dispersed over 14 chromosomes. The results obtained by multivariate analysis reveal significant effects of stud (P <.0001), age at measurement (P <.0001), and mean d2 (P =.0143). In univariate analyses, significant associations were obtained between length of pastern-hindlimbs and inbreeding coefficient (P <.01), length of cannons-hindlimb and mean d2 (P <.01), and length of neck and mean d2 (P <.001). After adjustment of single-test P values for multiple tests (Hochberg's step-up Bonferroni method), only the association of the length of neck and mean d2 remained significant (P =.0213). Thus, no overall large effects of inbreeding, microsatellite heterozygosity, and mean d2 on morphological traits were observed in the Lipizzan horse

Optimizing Carbon Storage Operations for Long-Term Safety

To combat global warming and mitigate the risks associated with climate change, carbon capture and storage (CCS) has emerged as a crucial technology. However, safely sequestering CO2 in geological formations for long-term storage presents several challenges. In this study, we address these issues by modeling the decision-making process for carbon storage operations as a partially observable Markov decision process (POMDP). We solve the POMDP using belief state planning to optimize injector and monitoring well locations, with the goal of maximizing stored CO2 while maintaining safety. Empirical results in simulation demonstrate that our approach is effective in ensuring safe long-term carbon storage operations. We showcase the flexibility of our approach by introducing three different monitoring strategies and examining their impact on decision quality. Additionally, we introduce a neural network surrogate model for the POMDP decision-making process to handle the complex dynamics of the multi-phase flow. We also investigate the effects of different fidelity levels of the surrogate model on decision qualities

Evaluation of the thermal stability of TiW/Cu heterojunctions using a combined SXPS and HAXPES approach

Power semiconductor device architectures require the inclusion of a diffusion barrier to suppress or at best prevent the interdiffusion between the copper metallization interconnects and the surrounding silicon substructure. The binary pseudo-alloy of titanium–tungsten (TiW), with &gt;70 at. % W, is a well-established copper diffusion barrier but is prone to degradation via the out-diffusion of titanium when exposed to high temperatures ([Formula: see text]400 [Formula: see text]C). Here, the thermal stability of physical vapor deposited TiW/Cu bilayer thin films in Si/SiO[Formula: see text](50 nm)/TiW(300 nm)/Cu(25 nm) stacks were characterized in response to annealing at 400 [Formula: see text]C for 0.5 h and 5 h, using a combination of soft and hard x-ray photoelectron spectroscopy and transmission electron microscopy. Results show that annealing promoted the segregation of titanium out of the TiW and interdiffusion into the copper metallization. Titanium was shown to be driven toward the free copper surface, accumulating there and forming a titanium oxide overlayer upon exposure to air. Annealing for longer timescales promoted a greater out-diffusion of titanium and a thicker oxide layer to grow on the copper surface. However, interface measurements suggest that the diffusion is not significant enough to compromise the barrier integrity, and the TiW/Cu interface remains stable even after 5 h of annealing