4,612 research outputs found

    Why cod don\u27t like to sunbathe: Quantity and quality in the animal kingdom

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    The difference between a cod and a lizard is not just a quantitative one. The recognition of qualitative differences between species does not imply a moral ranking. Our species’ special abilities to shape the earth mean we have a special responsibility for ensuring a liveable future for all organisms, human and non-human

    Yukawa enhancement of ZZ-mediated New Physics in ΔS=2\Delta S = 2 and ΔB=2\Delta B = 2 Processes

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    We discuss Yukawa-enhanced contributions from ZZ-mediated new physics to down-type quark ΔF=2\Delta F=2 processes in the framework of the standard model gauge-invariant effective theory (SMEFT). Besides the renormalization group (RG) mixing of the ZZ-mediating ψ2H2D\psi^2 H^2 D operators into ΔF=2\Delta F = 2 operators, we include at the electroweak scale one-loop (NLO) matching corrections consistently, necessary for the removal of the matching scale dependence. We point out that the right-handed ZZ-mediated interactions generate through Yukawa RG mixing ΔF=2\Delta F=2 left-right operators, which are further enhanced through QCD RG effects and chirally enhanced hadronic matrix elements. We investigate the impact of these new effects on the known correlations between ΔF=2\Delta F=2 and ΔF=1\Delta F=1 transitions in the SMEFT framework and point out qualitative differences to previous parameterizations of ZZ-mediated new physics that arise for the left-handed case. We illustrate how specific models fit into our model-independent framework by using four models with vector-like quarks. We carry out model-independent analyses of scenarios with purely left-handed and purely right-handed new-physics ZZ couplings for each of the three sectors s→ds\to d, b→sb\to s and b→db\to d. Specifically we discuss the correlations between ε′/ε\varepsilon'/\varepsilon, εK\varepsilon_K, KL→μ+μ−K_L\to \mu^+\mu^- K+→π+ννˉK^+\to \pi^+\nu\bar\nu and KL→π0ννˉK_L\to\pi^0\nu\bar\nu in the Kaon sector, and ϕs\phi_s, Bs→μ+μ−B_s\to\mu^+\mu^- and B→K(∗)(μ+μ−,ννˉ)B\to K^{(*)} (\mu^+\mu^-, \nu\bar\nu) in the b→sb\to s sector and Bd→μ+μ−B_d\to\mu^+\mu^- in the b→db\to d sector.Comment: 40 pages, 11 figures; v2: 2nd plot in figure 2 and references added, comparison with v2 of 1612.08839, conclusion unchanged; v3: improvements on text and presentation, matches published versio

    Reasoning in Many Dimensions : Uncertainty and Products of Modal Logics

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    Probabilistic Description Logics (ProbDLs) are an extension of Description Logics that are designed to capture uncertainty. We study problems related to these logics. First, we investigate the monodic fragment of Probabilistic first-order logic, show that it has many nice properties, and are able to explain the complexity results obtained for ProbDLs. Second, in order to identify well-behaved, in best-case tractable ProbDLs, we study the complexity landscape for different fragments of ProbEL; amongst others, we are able to identify a tractable fragment. We then study the reasoning problem of ontological query answering, but apply it to probabilistic data. Therefore, we define the framework of ontology-based access to probabilistic data and study the computational complexity therein. In the final part of the thesis, we study the complexity of the satisfiability problem in the two-dimensional modal logic KxK. We are able to close a gap that has been open for more than ten years

    Renal AA-amyloidosis in intravenous drug users - a role for HIV-infection?

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    Background: Chronic renal disease is a serious complication of long-term intravenous drug use (IVDU). Recent reports have postulated a changing pattern of underlying nephropathy over the last decades. Methods: Retrospective investigation including all patients with prior or present IVDU that underwent renal biopsy because of chronic kidney disease between 01.04.2002 and 31.03.2012 in the city of Frankfurt/Main, Germany. Results: Twenty four patients with IVDU underwent renal biopsy because of progressive chronic kidney disease or proteinuria. Renal AA-amyloidosis was the predominant cause of renal failure in 50% of patients. Membranoproliferative glomerulonephritis (GN) was the second most common cause found in 21%. Patients with AA-amyloidosis were more likely to be HIV infected (67 vs.17%; p=0.036) and tended to have a higher rate of repeated systemic infections (92 vs. 50%; p=0.069). Patients with AA-amyloidosis presented with progressive renal disease and nephrotic-range proteinuria but most patients had no peripheral edema or systemic hypertension. Development of proteinuria preceded the decline of GFR for approximately 1--2 years. Conclusions: AA-amyloidosis was the predominant cause of progressive renal disease in the last 10 years in patients with IVDU. The highest rate of AA-amyloidosis observed was seen in HIV infected patients with IVDU. We speculate that chronic HIV-infection as well as the associated immunosuppression might promote development of AA-amyloidosis by increasing frequency and duration of infections acquired by IVDU

    Fluorescence Correlation Spectroscopy as a Quantitative Tool Applied to Drug Delivery Model Systems

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    The delivery of drugs to cells is a very active area of research. Drugs are commonly believed to ameliorate illnesses. The targeted, controlled and/or enhanced uptake of the drug into cells is facilitated by loading the drug into carrier vehicles (nanoparticles, e.g.. micelles).The distribution of a drug over the nanoparticles used to deliver the drug to the targeted cells is of vital importance. It makes a difference, whether all nanoparticles carry the same amount of drug or whether a little amount of the nanoparticles carries a high proportion of the drug material and most nanoparticles carry no material. This depends on the method used to load the drugs into the carriers. Furthermore, the absolute amount of drug present in the nanoparticles and the absolute number of nanoparticles loaded with drug molecules is very important, because "dosis venum facit" [Paracelsus]. We present an approach to resolve these issues by optical means.If the drug is fluorescent or labeled with a fluorescent label, fluorescence correlation spectroscopy (FCS) can be used to determine quantitative size distributions with a (confocal) microscope. In order to determine absolute concentrations the spatial dimensions of the confocal observation volume have to be known. These can be obtained from numerical simulations using vectorial diffraction theory. The theoretical results have been compared with experimental results from FCS using the calibration dye Rhodamine 6G. In a straightforward procedure the results were corrected for adsorption effects and excellent agreement to the theory was foun

    Methodological comparison of agent models

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    Hybrid agent architectures comprise the radical change of paradigms in AI over the past decades by reconciling the different styles of reactive, deliberative, even social systems. They have been successfully applied to a range of complex real-world domains. Due to their originally informal background, a verification of design goals in derived implementations, theoretical foundations, and a detailed comparison with other agent models have not yet been obvious. The present work proposes a formal methodology to bridge the gap between theoretical and practical aspects especially of hybrid designs, such as the layered INTERRAP. The employed, connected stages of specification, i.e., architecture, computational model, theory, proof calculus, and implementation, also provide a yet unique framework for comparing heterogeneous agent models including unified and logic-based ones. Based on recent work on INTERRAP, we demonstrate that this methodology allows to compare state-of-the-art designs from robotics, AI, computer science, and cognitive science with respect to a spectrum of inherent properties along the two dimensions of abstraction and declarativity. This supports our claim that INTERRAP is a coherent and advanced account of layered agency including goal-oriented abstraction planning in on-line interaction with reactive skills and social reasoning. We also derive particular research issues to guide the future development of INTERRAP

    Combining DL-LiteNbool with branching time: a gentle marriage

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    We study combinations of the description logic DL-Lite_{bool}^N with the branching temporal logics CTL* and CTL. We analyse two types of combinations, both with rigid roles: (i) temporal operators are applied to concepts and to ABox assertions, and (ii) temporal operators are applied to concepts and Boolean combinations of concept inclusions and ABox assertions. For the resulting logics, we present algorithms for the satisfiability problem and (mostly tight) complexity bounds ranging from ExpTime to 3ExpTime
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