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Abstract: A novel scheme of plasma simulation particularly suited for computing the one-dimensional nonlinear evolution of parallel propagating solar wind Alfvén waves is presented. The scheme is based on the Vlasov and the MHD models, for solving the longitudinal and the transverse components, respectively. As long as the nonlinearity is not very large (so that the longitudinal and transverse components are well separated), our Vlasov–MHD model can correctly describe evolution of finite amplitude parallel Alfvén waves, which are typical in the solar wind, both in the linear and nonlinear stages. The present model can be applied to discussions of phenomena where the parallel Alfvén waves play major roles, for example, the solar coronal heating and solar wind acceleration by the Alfvén waves propagating from the photosphere. [Copyright &y& Elsevier]

Rationale and Objectives: To compare the effectiveness of chest dual-energy subtraction digital tomosynthesis (DES-DT) imaging with that of DES radiography for detecting simulated pulmonary nodules with and without calcifications. Materials and Methods: A DES-DT and DES radiography system (SonialVision Safire II, Shimadzu Co, Kyoto, Japan) with pulsed x-rays and rapid kV switching was used to detect simulated pulmonary nodules (5 and 7 mmφ, ground-glass opacity). Low-voltage (60 kVp), high-voltage (120 kVp), and soft-tissue or bone-subtracted tomograms of the desired layer thicknesses were reconstructed from the image data acquired during a single tomographic scan using a three-dimensional filtered back-projection algorithm, bone- and soft tissue‑subtracted images, and a scan angle of 40°. In the analysis, we considered the signal-to-noise ratio (SNR) computed for various sizes and degree of calcification of the simulated pulmonary nodules. We examined 30 samples with and 30 samples without different degrees of simulated pulmonary nodules by both DES radiography and DES-DT imaging. Based on the evaluations of five thoracic radiologists, receiver operating characteristic curves were compared to assess the detection accuracy of the two methods. Results: SNR and quality of images obtained by DES-DT imaging were significantly superior to those obtained by DES radiography. Based on the results of the ROC analysis, the detection accuracy of DES-DT was significantly greater than that of DES radiography (7 mmφ without calcification P < .03; with calcification P < .003). Conclusion: DES-DT imaging exhibited greater sensitivity than DES radiography for detecting simulated nodules, especially large nodules, with and without calcifications. [ABSTRACT FROM AUTHOR]

Summary: Objective: To investigate relationship between serum hyaluronan (HA) level and the presence and severity of radiographic knee osteoarthritis (OA) as well as degree of knee pain in Japanese population. Design: A total of 616 volunteers participated in this study. Based on the Kellgren–Lawrence (K–L) grade, participants were radiographically classified into three groups: Normal (K–L grade 0 or 1), Moderate (grade 2) and Severe (grade 3 or 4). The degree of knee pain was quantified by visual analogue scale (VAS) and Knee injury and Osteoarthritis Outcome Score (KOOS) Pain. Serum HA levels were compared among the Normal, Moderate and Severe groups, and the relationship between serum HA level and the severity of knee OA was analyzed after age, sex and body mass index (BMI) were adjusted. In addition, the correlation between serum HA level and the degree of knee pain was analyzed in each group. Results: Regarding relationship between serum HA level and the severity of radiographic knee OA, serum HA levels of the Moderate and Severe groups were significantly higher than in the Normal group (P <0.001). Furthermore, serum HA level correlated with the severity of radiographic knee OA (r =0.289, P <0.001) after adjusting for age, sex and BMI. Serum HA level correlated with VAS of knee pain and/or KOOS Pain in the Normal and Moderate groups. Conclusion: Serum HA level has the potential to be useful for the diagnosis of the presence and severity of knee OA. [ABSTRACT FROM AUTHOR]

We report on the status of our QCD thermodynamics project. It is performed on the QCDOC machine at Brookhaven National Laboratory and the APEnext machine at Bielefeld University. Using a 2+1 flavor formulation of QCD at almost realistic quark masses we calculated several thermodynamical quantities. In this proceeding we show the susceptibilites of the chiral condensate and the Polyakov loop, the static quark potential and the spatial string tension. [Copyright &y& Elsevier]

Abstract: Photovoltaic properties of the cells consisting of a heterojunction of conducting polymer-fullerene systems and a semiconductor oxide thin film, which is transparent in the visible-wavelength range, have been investigated. Introducing the transparent semiconductor oxide, such as zinc oxide (ZnO), into the photovoltaic cells with conducting polymer - fullerene systems, high performance has been obtained. Especially in the layered photovoltaic cells with the structure of ITO/ZnO/C60/PAT6/Au, the high monochromatic energy conversion efficiency and the external quantum efficiency have been realized. The photovoltaic properties have been interpreted by the effective absorption of incident photons around the interface of conducting polymer and fullerene, the interpenetrated fullerene/conducting polymer interface involving the efficient photo-induced charge transfer, and the short distance between the electron-generation region and electrode, resulting in the enhancement of the electron collection to the electrode. [Copyright &y& Elsevier]

Abstract: We propose a fixed scale approach to calculate the equation of state (EOS) in lattice QCD. In this approach, the temperature T is varied by at fixed lattice spacings. This enables us to reduce simulations which are required to provide basic data in finite temperature studies but are quite expensive in the conventional fixed- approach. Since the conventional integral method to obtain the pressure is inapplicable at fixed scale, we introduce a new method, “T-integration method”, to calculate pressure non-perturbatively. We test the fixed scale approach armed with the T-integral method in quenched QCD on isotropic and anisotropic lattices. Our method is found to be powerful to obtain reliable results for the equation of state, especially at intermediate and low temperatures. Reduction of the computational cost of simulations is indispensable to study EOS in QCD with dynamical quarks. The status of our study in QCD with improved Wilson quarks is also reported. [Copyright &y& Elsevier]