Noch Platz für Nischen? - Bedeutung und Potential alter und gefährdeter Rinderrassen im Ökologischen Landbau

Not only the biodiversity of wild species, but also the diversity in livestock is declining rapidly: Out of 6.300 registered livestock breeds in the world 1.250 are endangered or already extinct. In Germany 16 out of 32 cattle breeds are endangered, while three of the most popular cattle breeds make up 92 % of the more than two million herd-book cows. Due to their adaptation to local conditions on first sight many rare and endangered cattle breeds appear to be well suited for organic farming systems, but the percentage of rare breeds on organic farms is not much higher than on conventional ones. Council Regulation (EC) No 1804/1999 on livestock production in organic farming recommends to encourage biological diversity and to favour the use of breeds which are already adopted to the local conditions. This paper summarises a study on the motivations of organic farmers for keeping rare and endangered cattle breeds, and on which role breeding issues and livestock biodiversity play for organic farming organisations and controlling agencies. The main reasons for keeping rare cattle breeds were good fodder utilization, low susceptibility to diseases, good adaptation to local conditions, but above all a personal relation to a specific breed. Conservation aspects and breed-specific subsidies were of lower importance. Nevertheless, husbandry of rare cattle breeds should be economically viable. Unfortunately most organic farming organisations and controlling agencies hardly touched on breeding and choice-of-breed aspects in their advisory work; they more or less shared the view that the issue was of minor importance for organic farms. The paper concludes with a vision under which conditions rare cattle breeds could be better integrated into organic farming systems and on how organic farming could contribute to the in-situ conservation of livestock genetic resources

An evaluation of |Vus| and precise tests of the Standard Model from world data on leptonic and semileptonic kaon decays

We present a global analysis of leptonic and semileptonic kaon decay data, including all recent results published by the BNL-E865, KLOE, KTeV, ISTRA+ and NA48 experiments. This analysis, in conjunction with precise lattice calculations of the hadronic matrix elements now available, leads to a very precise determination of |Vus| and allows us to perform several stringent tests of the Standard Model.Comment: LaTeX, 25 pages, 12 figures, 16 tables. Submitted to EPJC. v2: Minor changes for accepted version. No numerical results change

Terahertz photoconductivity and plasmon modes in double-quantum-well field-effect transistors

Double-quantum-well field-effect transistors with a grating gate exhibit a sharply resonant, voltage tuned terahertz photoconductivity. The voltage tuned resonance is determined by the plasma oscillations of the composite structure. The resonant photoconductivity requires a double-quantum well but the mechanism whereby plasma oscillations produce changes in device conductance is not understood. The phenomenon is potentially important for fast, tunable terahertz detectors

Precision tests of the Standard Model with leptonic and semileptonic kaon decays

We present a global analysis of leptonic and semileptonic kaon decays data, including all recent results by BNL-E865, KLOE, KTeV, ISTRA+, and NA48. Experimental results are critically reviewed and combined, taking into account theoretical (both analytical and numerical) constraints on the semileptonic kaon form factors. This analysis leads to a very accurate determination of Vus and allows us to perform several stringent tests of the Standard Model

Community prevalence of antibodies to human immunodeficiency virus in Rural and Urban Vellore, Tamil Nadu

Background: Human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS) are becoming increasingly common in India. Currently, antenatal prevalence is a surrogate marker for HIV prevalence in the community. The association between antenatal and community prevalence of HIV needs to be validated so that estimates can be verified or adjusted appropriately Methods: A probability proportional to size cluster survey was conducted in the Kaniyambadi block of Vellore district and in the urban wards of Vellore town to estimate the prevalence of antibodies to rubella from August 1999 to February 2000. All personal identifier data from the serum samples were removed to yield a collection for which only the age and sex were known. Estimation of antibodies to HIV in sera from individuals between 15 and 40 years of age, was carried out by one screening ELISA and the reactive sera were further subjected to a supplementary test. Results: We tested 1512 serum samples from subjects residing in rural areas and 1358 samples from those residing in urban areas. The seropositivity among rural samples was 0.66% and among urban samples 1.4%. The prevalence was almost equal among men and women and the youngest infected individual was 15 years old. Conclusion: The prevalence of HIV during the period of study was similar to the national surveillance data for Tamil Nadu based on antenatal women. HIV prevalence differs in urban and rural Tamil Nadu, with urban areas having a higher burden of the disease

A structural vector autoregressive model of technical efficiency and delays with an application to Chinese airlines

Abstract This study reports on the performance assessment of Chinese airlines from 2006 to 2014 using a stochastic distance function where technical efficiency and a measure of flight delays follow a joint structural autoregressive process. This model is used to investigate whether technical efficiency causes flight punctuality or the other way around. The model, however, yields a non-trivial likelihood function and is not amenable to estimation using least squares or standard maximum likelihood techniques. To estimate the model therefore, we propose and implement maximum simulated likelihood with importance sampling. The results suggest a mutual dependence (feedback) between technical efficiency and delays. Policy implications are derived

Assessing the strategic fit of potential M&As in Chinese banking:A novel Bayesian stochastic frontier approach

Banking in China is well-known for being extremely fragmented, thus making the analysis of the sector not a straightforward task. This study aims to explore the strategic fit of potential mergers and acquisitions in the Chinese banking industry. When the operations of two banks are jointly analyzed this means that the inputs and the outputs of these two individual banks are somehow combined in an attempt to better understand the sector as a whole. A novel SFA model with Bayesian inference on input/output prices is proposed to assess the impact of business-related variables on efficiency levels. The results not only reveal that bank size, type, and origin present a significant impact on individual technical efficiency levels, but also exert a significant impact on the efficiency frontier of the industry. The strategic fit of M&As in the Chinese banking industry strongly relies on opportunities derived from banking automation that may arise from acquiring technologically obsolete small banks. Big and foreign banks also exert a positive impact on the technological catch-up of Chinese banks, which may suggest opportunities for sector deregulation

Motif effects in Affymetrix GeneChips seriously affect probe intensities

An Affymetrix GeneChip consists of an array of hundreds of thousands of probes (each a sequence of 25 bases) with the probe values being used to infer the extent to which genes are expressed in the biological material under investigation. In this article, we demonstrate that these probe values are also strongly influenced by their precise base sequence. We use data from >28 000 CEL files relating to 10 different Affymetrix GeneChip platforms and involving nearly 1000 experiments. Our results confirm known effects (those due to the T7-primer and the formation of G-quadruplexes) but reveal other effects. We show that there can be huge variations from one experiment to another, and that there may also be sizeable disparities between batches within an experiment and between CEL files within a batch. © 2012 The Author(s)

Dyslipidemia among HIV-infected Patients with Tuberculosis Taking Once-daily Nonnucleoside Reverse-Transcriptase Inhibitor–Based Antiretroviral Therapy in India

HIV-infected patients with tuberculosis who initiate nonnucleoside reverse-transcriptase-based anti-retroviral treatment in combination with rifampicin-based antituberculosis treatment demonstrate increases in total cholesterol, low-density cholesterol, and high-density cholesterol levels but no change in blood glucose level after 1 year. Cholesterol increases were more frequent among patients receiving efavirenz

Qualitative yaw stability analysis of free-yawing downwind turbines

This article qualitatively shows the yaw stability of a free-yawing downwind turbine and the ability of the turbine to align passively with the wind direction using a model with 2 degrees of freedom. An existing model of a Suzlon S111 upwind 2.1&thinsp;MW turbine is converted into a downwind configuration with a 5∘ tilt and a 3.5∘ downwind cone angle. The analysis shows that the static tilt angle causes a wind-speed-dependent yaw misalignment of up to −19∘ due to the projection of the torque onto the yaw bearing and the skewed aerodynamic forces caused by wind speed projection. With increased cone angles, the yaw stiffness can be increased for better yaw alignment and the stabilization of the free-yaw motion. The shaft length influences the yaw alignment only for high wind speeds and cannot significantly contribute to the damping of the free-yaw mode within the investigated range. Asymmetric flapwise blade flexibility is seen to significantly decrease the damping of the free-yaw mode, leading to instability at wind speeds higher than 19&thinsp;m&thinsp;s−1. It is shown that this additional degree of freedom is needed to predict the qualitative yaw behaviour of a free-yawing downwind wind turbine.</p