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Risk Priority Number: A Measuring Instrument for Hygienic Management on Broiler Farms, Reflecting Their Campylobacter Status
Monika Matt,Hans Peter Stüger,Peter Pless
Agriculture , 2013, DOI: 10.3390/agriculture3040700
Abstract: Hygiene management is essential for rearing Campylobacter free broiler flocks. In this study, several hygiene factors (e.g., thinning, water supply, stable cloths, stable condition, stable environment, etc.) are categorized and aggregated in a developed risk priority number (RPN). This number is measuring the quality of hygiene management of a broiler farm with one single value (range: 801–4005 points), the higher the RPN, the better is the hygiene status. The distribution of the values is left skewed and none of the 53 examined Austrian broiler farms reached the maximum. Cecal samples ( n = 610) from broilers at the point of slaughter determined the Campylobacter status of the farms. Farms with a high RPN consistently produced more Campylobacter free batches than farms with a low RPN. Ranking of the broiler farms based on their RPN was significantly correlated with their microbiological results for Campylobacter detection (Spearman’s correlation coefficient = 0.646). The risk priority number is an easy tool for the assessment and measurement of the hygiene management system at a broiler farm. Besides the educational benefits of the RPN, benchmarking against the mean value or the maximum is possible.
The Cosmological Constant Problem from a Brane-World Perspective
Stefan Forste,Zygmunt Lalak,Stéphane Lavignac,Hans Peter Nilles
Physics , 2000, DOI: 10.1088/1126-6708/2000/09/034
Abstract: We point out several subtleties arising in brane-world scenarios of cosmological constant cancellation. We show that solutions with curvature singularities are inconsistent, unless the contribution to the effective four-dimentional cosmological constant of the physics that resolves the singularities is fine-tuned. This holds for both flat and curved branes. Irrespective of this problem, we then study an isolated class of flat solutions in models where a bulk scalar field with a vanishing potential couples to a 3-brane. We give an example where the introduction of a bulk scalar potential results in a nonzero cosmological constant. Finally we comment on the stability of classical solutions of the brane system with respect to quantum corrections.
Target-Space Duality in Heterotic and Type I Effective Lagrangians
Zygmunt Lalak,Stéphane Lavignac,Hans Peter Nilles
Physics , 1999, DOI: 10.1016/S0550-3213(00)00132-2
Abstract: We study the implications of target-space duality symmetries for low-energy effective actions of various four-dimensional string theories. In the heterotic case such symmetries can be incorporated in simple orbifold examples. At present a similar statement cannot be made about the simplest type IIB orientifolds due to an obstruction at the level of gravitational anomalies. This fact confirms previous doubts concerning a conjectured heterotic-type IIB orientifold duality and shows that target-space symmetries can be a powerful tool in studying relations between various string theories at the level of the effective low-energy action. Contraints on effective Lagrangians from these symmetries are discussed in detail. In particular, we consider ways of extending T-duality to include additional corrections to the Kaehler potential in heterotic string models with N=2 subsectors.
String Dualities in the Presence of Anomalous U(1) Symmetries
Zygmunt Lalak,Stéphane Lavignac,Hans Peter Nilles
Physics , 1999, DOI: 10.1016/S0550-3213(99)00400-9
Abstract: Anomalous U(1) gauge symmetries in type II orientifold theories show some unexpected properties. In contrast to the heterotic case, the masses of the gauge bosons are in general of order of the string scale even in the absence of large Fayet-Iliopoulos terms. Despite this fact, the notion of heterotic-type II orientifold duality remains a useful concept, although this symmetry does not seem to hold in all cases considered. We analyse the status of this duality symmetry, clarify the properties of anomalous U(1) gauge symmetry in the orientifold picture and comment on the consequences for phenomenological applications of such anomalous gauge symmetries.
Is magnetic chiral dichroism feasible with electron vortices?
Peter Schattschneider,Stefan L?ffler,Michael Stger-Pollach,Johan Verbeeck
Physics , 2013,
Abstract: We discuss the feasibility of detecting magnetic transitions with focused electron vortex probes, suggested by selection rules for the magnetic quantum number. We theoretically estimate the dichroic signal strength in the L$_{2,3}$ edge of the ferromagnetic d metals. It is shown that under realistic conditions, the dichroic signal is undetectable for nanoparticles larger than ~1 nm. This is confirmed by a key experiment with nanometer sized vortices.
Magnetic circular dichroism in EELS: Towards 10 nm resolution
Peter Schattschneider,Cécile Hébert,Stefano Rubino,Michael Stger-Pollach,Jan Rusz,Pavel Novák
Physics , 2007, DOI: 10.1016/j.ultramic.2007.07.002
Abstract: We describe a new experimental setup for the detection of magnetic circular dichroism with fast electrons (EMCD). As compared to earlier findings the signal is an order of magnitude higher, while the probed area could be significantly reduced, allowing a spatial resolution of the order of 30 nm. A simplified analysis of the experimental results is based on the decomposition of the Mixed Dynamic Form Factor S(q,q',E) into a real part related to the scalar product and an imaginary part related to the vector product of the scattering vectors q and q'. Following the recent detection of chiral electronic transitions in the electron microscope the present experiment is a crucial demonstration of the potential of EMCD for nanoscale investigations.
Review of teriflunomide and its potential in the treatment of multiple sclerosis
Clemens Warnke, Gerd Meyer zu H rste, Hans-Peter Hartung, Olaf Stüve, et al.
Neuropsychiatric Disease and Treatment , 2009, DOI: http://dx.doi.org/10.2147/NDT.S4474
Abstract: f teriflunomide and its potential in the treatment of multiple sclerosis Review (7881) Total Article Views Authors: Clemens Warnke, Gerd Meyer zu H rste, Hans-Peter Hartung, Olaf Stüve, et al. Published Date May 2009 Volume 2009:5 Pages 333 - 340 DOI: http://dx.doi.org/10.2147/NDT.S4474 Clemens Warnke1, Gerd Meyer zu H rste1, Hans-Peter Hartung1, Olaf Stüve2,3,4, Bernd C Kieseier1 1Department of Neurology, Heinrich-Heine-University Düsseldorf, Germany; 2Neurology Section, VA North Texas Health Care System, Medical Service, Dallas, TX, USA; 3Department of Neurology; 4Department of immunology, University of Texas Southwestern Medical Center at Dallas, TX, USA Abstract: In the light of new cases of progressive multifocal leukoencephalopathy and induced autoimmunity in multiple sclerosis (MS) patients who received treatment with upcoming disease-modifying immunosuppressant drugs with a highly specific mode of action such as natalizumab, rituximab, or alemtuzumab, alternative oral treatment options for a subgroup of less severely affected MS patients are a major focus of drug development. These agents are currently investigated in phase III clinical trials and some of them are characterized by a favorable safety profile. With an emphasis on teriflunomide, the active metabolite of an immunosuppressant approved for the treatment of rheumatoid arthritis since 1998, a number of oral treatment options for patients with MS are discussed.
The Likoma Network Study: Context, data collection and initial results
Stéphane Helleringer,Hans-Peter Kohler,Agnes Chimbiri,Praise Chatonda
Demographic Research , 2009,
Abstract: The extent and structure of sexual networks have important consequences for the spread of sexually transmitted diseases such as HIV. However, very few datasets currently exist that allow a detailed investigation of sexual networks in sub-Saharan African settings where HIV epidemics have become generalized. In this paper, we describe the context and methods of the Likoma Network Study (LNS), one of the few studies that have collected extensive information on sexual networks in sub-Saharan Africa. We start by reviewing theoretical arguments and empirical studies emphasizing the importance of network structures in the epidemiology of HIV and other sexually transmitted infections (STI). The island setting of this study is described, and we argue that the choice of an island as a research site limited potential biases that may make the collection of sexual network data difficult. We then document our empirical strategy for the collection of sexual network data and the subsequent identification of sexual network partners. A description of the protocol for the collection of biomarker data (HIV infection) is provided. Finally, we present initial results relating to the socioeconomic context of the island, the size and composition of sexual networks, the quality of the sexual network data, the determinants of successful contact tracing during the LNS, and the prevalence of HIV in the study population.
Molecular modelling and simulation of the surface tension of real quadrupolar fluids
Stephan Werth,Katrin St?bener,Peter Klein,Karl-Heinz Küfer,Martin Horsch,Hans Hasse
Physics , 2014,
Abstract: Molecular modelling and simulation of the surface tension of fluids with force fields is discussed. 29 real fluids are studied, including nitrogen, oxygen, carbon dioxide, carbon monoxide, fluorine, chlorine, bromine, iodine, ethane, ethylene, acetylene, propyne, propylene, propadiene, carbon disulfide, sulfur hexafluoride, and many refrigerants. The fluids are represented by two-centre Lennard-Jones plus point quadrupole models from the literature. These models were adjusted only to experimental data of the vapour pressure and saturated liquid density so that the results for the surface tension are predictions. The deviations between the predictions and experimental data for the surface tension are of the order of 20 percent. The surface tension is usually overestimated by the models. For further improvements, data on the surface tension can be included in the model development. A suitable strategy for this is multi-criteria optimization based on Pareto sets. This is demonstrated using the model for carbon dioxide as an example.
Preface
Alois Stger
International Journal of Integrated Care , 2009,
Abstract:
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