Nosoden zum Trockenstellen – eine placebokontrollierte Blindstudie

In an organic dairy herd (250 cows) a homeopathic dry cow treatment should be evaluated while an antibiotic dry cow therapy (DCT) was totally abandoned. A ran-domized placebo-controlled double blind study with a herd specific nosode (D30) was conducted. Either 5 ml of the nosode (VG) or a placebo (KG) was orally administered in weekly intervals four times before drying off, at the day of calving and seven days post partum (p.p.). The efficacy of treatment was measured according to quarter foremilk samples at the days of treatment, six weeks p.p. and at the end of the 2nd and 3rd month of lactation. Data of 129 cows with 512 quarters (VG:n=65/260; KG:n=64/252) was evaluable. New intramammary infections (IMIn) cure rates and cases of clinical mastitis in both treatment groups were nearly identical. In the VG 20% of the quarters came along with IMIn. In the KG IMIn were about 5% higher along the observation period (p>0.05). The cure rates of infected quarters were about 40% in both treatment groups (p>0.05). The complete abdication of antibiotics in DCT did not cause an impairment of udder health. Moreover the number of healthy quarters in-creased and the mean bulk milk somatic cell count decreased slightly during the study. The results of the study show that the use of antibiotics can be highly de-creased though a minimal use is indispensable, especially in herds suffering from udder health problems. Still the most essential prophylactic task is to optimize the housing conditions in the dry period and around calving. The presented dry cow man-agement in conjunction with a selective use of antibiotics can be implemented in veterinary herd health programs on other dairy farms

An adaptive multiscale quasicontinuum approach for mechanical simulations of elastoplastic periodic lattices

The quasicontinuum method is a multiscale method that combines locally supported coarse-grained domains, with small regions in which the microstructural model is fully resolved. This contribution proposes the first adaptive formulation of the method for microstructural elastoplasticity. The microstructural model uses an elastoplastic beam description. The indicator for refinement is the occurrence of plastic deformation, such that plasticity can only occur in fully resolved regions. An illustrative numerical example of a scratch test of an elastoplastic Kelvin lattice demonstrates the capabilities of the resulting framework

Filament Path Optimization with Curvilinear Trajectories for Additive Manufacturing of Load-Bearing Components

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Gate-control of superconducting current: mechanisms, parameters and technological potential

In conventional metal-oxide semiconductor (CMOS) electronics, the logic state of a device is set by a gate voltage (VG). The superconducting equivalent of such effect had remained unknown until it was recently shown that a VG can tune the superconducting current (supercurrent) flowing through a nanoconstriction in a superconductor. This gate-controlled supercurrent (GCS) effect can lead to superconducting logics like CMOS logics, but with lower energy dissipation. The physical mechanism underlying the GCS effect, however, remains under debate. In this review article, we illustrate the main mechanisms proposed for the GCS effect, and the material and device parameters that mostly affect it based on the evidence reported. We will come to the conclusion that different mechanisms are at play in the different studies reported so far. We then outline studies that can help answer open questions on the effect and achieve control over it, which is key for applications. We finally give insights into the impact that the GCS effect can have towards high-performance computing with low-energy dissipation and quantum technologies.Comment: 23 pages, 5 figures, 2 table

An early history of T cell-mediated cytotoxicity.

After 60 years of intense fundamental research into T cell-mediated cytotoxicity, we have gained a detailed knowledge of the cells involved, specific recognition mechanisms and post-recognition perforin-granzyme-based and FAS-based molecular mechanisms. What could not be anticipated at the outset was how discovery of the mechanisms regulating the activation and function of cytotoxic T cells would lead to new developments in cancer immunotherapy. Given the profound recent interest in therapeutic manipulation of cytotoxic T cell responses, it is an opportune time to look back on the early history of the field. This Timeline describes how the early findings occurred and eventually led to current therapeutic applications

Physical environmental factors that invite older adults to walk for transportation

Knowledge on the physical environmental factors that invite older adults to walk for transportation is limited. The current study aimed to investigate the relationships between environmental factors and invitingness to walk for transportation and the potential moderating effects of gender, functional limitations and current walking for transportation behavior. Sixty older participants evaluated 40 panoramic photographs on their invitingness in two ways: a forced choice (first impressions) and a rating task (more deliberate evaluation). Presence of vegetation, benches, and surveillance significantly positively related to both invitingness-measures. Upkeep and presence of historic elements significantly positively related to the assigned invitingness-ratings. For the forced choice task, significant positive relationships emerged for land use and separation between sidewalk and cycling path, but only in functionally limited participants. Environments offering comfort, safety from crime, and pleasantness may attract older adults to walk for transportation. Experimental and on-site studies are needed to elaborate on current findings

A new framework for cortico-striatal plasticity: behavioural theory meets In vitro data at the reinforcement-action interface

Operant learning requires that reinforcement signals interact with action representations at a suitable neural interface. Much evidence suggests that this occurs when phasic dopamine, acting as a reinforcement prediction error, gates plasticity at cortico-striatal synapses, and thereby changes the future likelihood of selecting the action(s) coded by striatal neurons. But this hypothesis faces serious challenges. First, cortico-striatal plasticity is inexplicably complex, depending on spike timing, dopamine level, and dopamine receptor type. Second, there is a credit assignment problem—action selection signals occur long before the consequent dopamine reinforcement signal. Third, the two types of striatal output neuron have apparently opposite effects on action selection. Whether these factors rule out the interface hypothesis and how they interact to produce reinforcement learning is unknown. We present a computational framework that addresses these challenges. We first predict the expected activity changes over an operant task for both types of action-coding striatal neuron, and show they co-operate to promote action selection in learning and compete to promote action suppression in extinction. Separately, we derive a complete model of dopamine and spike-timing dependent cortico-striatal plasticity from in vitro data. We then show this model produces the predicted activity changes necessary for learning and extinction in an operant task, a remarkable convergence of a bottom-up data-driven plasticity model with the top-down behavioural requirements of learning theory. Moreover, we show the complex dependencies of cortico-striatal plasticity are not only sufficient but necessary for learning and extinction. Validating the model, we show it can account for behavioural data describing extinction, renewal, and reacquisition, and replicate in vitro experimental data on cortico-striatal plasticity. By bridging the levels between the single synapse and behaviour, our model shows how striatum acts as the action-reinforcement interface