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71.
72.
We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.  相似文献   
73.
We investigate how models for neutrino–nucleus cross sections based on different assumptions for the nuclear dynamics affect the forecasted sensitivities to neutrino oscillation parameters at future neutrino facilities. We limit ourselves to the quasi-elastic regime, where the neutrino cross sections can be evaluated with less uncertainties, and discuss the sensitivity reach to θ13θ13 and δ at a prototype low-γ β-beam, mostly sensitive to the quasi-elastic regime.  相似文献   
74.
The dynamics of a point-like relativistic particle with respect of the proper time is formulated on the hyperboloid p 2 0p 2=M 2 c 2. The Hamilton-Jacobi equations on the hyperboloid are derived for the particles with mass (M 2=m 2, m>0), for the particles with zero-mass (M=0, m>0), and for the neutrino. It is shown, in a certain factorization of the momentum, the model can be identified with Nambu's three-dimensional phase space formalism. A first quantized version of the model is formulated according to a canonical scheme of quantization (Schrödinger quantization scheme).  相似文献   
75.
An interior penalty method and a compact discontinuous Galerkin method are proposed and compared for the solution of the steady incompressible Navier–Stokes equations. Both compact formulations can be easily applied using high‐order piecewise divergence‐free approximations, leading to two uncoupled problems: one associated with velocity and hybrid pressure, and the other one only concerned with the computation of pressures in the elements interior. Numerical examples compare the efficiency and the accuracy of both proposed methods. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
76.
A series of methyl-2,6-diaryl-1-methyl-4-oxopiperidine-3,5-dicarboxylates Ia-c and 2,4-diaryl-3,7-dimethyl-1,5-dimethoxycarbonyl-9-bispidinones IIa-c have been synthesized and studied by ir, 1H and 13C nmr spectroscopy and the crystal structure of methyl 2,4-diphenyl-3,7-dimethyl-9-oxo-3,7-diazabicyclo[3,3.1]nonane-1,5-dicarboxylate (IIa) has been determined by X-ray diffraction. The enolic form of compound Ia (I'a) was also studied.  相似文献   
77.
The object of this paper is to provide a systematic treatment of bargaining procedures as a basis for negotiation. An innovative fuzzy logic approach to analyze n-person cooperative games is developed. A couple of indices, the Good Deal Index and the Counterpart Convenience Index are proposed to characterize the heuristic of bargaining and to provide a solution concept. The indices are examined theoretically and experimentally by analyzing three case studies. The results verify the validity of the approach.  相似文献   
78.
Retinol degrades rapidly in light into a variety of photoproducts. It is remarkable that visual cycle retinoids can evade photodegradation as they are exchanged between the photoreceptors, retinal pigment epithelium and Müller glia. Within the interphotoreceptor matrix, all‐trans retinol, 11‐cis retinol and retinal are bound by interphotoreceptor retinoid‐binding protein (IRBP). Apart from its role in retinoid trafficking and targeting, could IRBP have a photoprotective function? HPLC was used to evaluate the ability of IRBP to protect all‐trans and 11‐cis retinols from photodegradation when exposed to incandescent light (0 to 8842 μW cm?2); time periods of 0–60 min, and bIRBP: retinol molar ratios of 1:1 to 1:5. bIRBP afforded a significant prevention of both all‐trans and 11‐cis retinol to rapid photodegradation. The effect was significant over the entire light intensity range tested, and extended to the bIRBP: retinol ratio 1:5. In view of the continual exposure of the retina to light, and the high oxidative stress in the outer retina, our results suggest IRBP may have an important protective role in the visual cycle by reducing photodegradation of all‐trans and 11‐cis retinols. This role of IRBP is particularly relevant in the high flux conditions of the cone visual cycle.  相似文献   
79.
80.
Throughout history, poor quality medicines have been a persistent problem, with periodical crises in the supply of antimicrobials, such as fake cinchona bark in the 1600s and fake quinine in the 1800s. Regrettably, this problem seems to have grown in the last decade, especially afflicting unsuspecting patients and those seeking medicines via on-line pharmacies. Here we discuss some of the challenges related to the fight against poor quality drugs, and counterfeits in particular, with an emphasis on the analytical tools available, their relative performance, and the necessary workflows needed for distinguishing between genuine, substandard, degraded and counterfeit medicines.  相似文献   
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