1,069 research outputs found

    Is cosmological constant screened in Liouville gravity with matter?

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    There has been a proposal that infrared quantum effects of massless interacting field theories in de-Sitter space may provide time-dependent screening of the cosmological constant. As a concrete model of the proposal, we study the three loop corrections to the energy-momentum tensor of massless λϕ4\lambda \phi^4 theory in the background of classical Liouville gravity in D=2D=2 dimensional de-Sitter space. We find that the cosmological constant is screened in sharp contrast to the massless λϕ4\lambda \phi^4 theory in D=4D=4 dimensions due to the sign difference between the cosmological constant of the Liouville gravity and that of the Einstein gravity. To argue for the robustness of our prediction, we introduce the concept of time-dependent infrared counter-terms and examine if they recover the de-Sitter invariance in the λϕ4\lambda \phi^4 theory in comparison with the Sine-Gordon model where it was possible.Comment: 28 pages, 7 eps figure

    Electronic Structure and Magnetic Properties of N@C60-SWCNT

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    Developmental changes in expression, subcellular distribution, and function of Drosophila N-cadherin, guided by a cell-intrinsic program during neuronal differentiation

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    Cell adhesion molecules (CAMs) perform numerous functions during neural development. An individual CAM can play different roles during each stage of neuronal differentiation; however, little is known about how such functional switching is accomplished. Here we show that Drosophila N-cadherin (CadN) is required at multiple developmental stages within the same neuronal population and that its sub-cellular expression pattern changes between the different stages. During development of mushroom body neurons and motoneurons, CadN is expressed at high levels on growing axons, whereas expression becomes downregulated and restricted to synaptic sites in mature neurons. Phenotypic analysis of CadN mutants reveals that developing axons require CadN for axon guidance and fasciculation, whereas mature neurons for terminal growth and receptor clustering. Furthermore, we demonstrate that CadN downregulation can be achieved in cultured neurons without synaptic contact with other cells. Neuronal silencing experiments using Kir_2.1 indicate that neuronal excitability is also dispensable for CadN downregulation in vivo. Interestingly, downregulation of CadN can be prematurely induced by ectopic expression of a nonselective cation channel, dTRPA1, in developing neurons. Together, we suggest that switching of CadN expression during neuronal differentiation involves regulated cation influx within neurons

    Improvement of Experimentally Induced Hepatic and Renal Disorders in Rats using Lactic Acid Bacteria-fermented Soybean Extract (Biofermentics™)

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    The effects of lactic acid bacteria-fermented soybean extract (Biofermentics™; BF) on experimental models of hepatic and renal disorders were investigated in vivo and in vitro. In rat, hepatitis induced by feeding of deoxycholic acid (DCA, 0.5 wt/wt, n = 6) or intraperitoneal injection of d-galactosamine (GMN, 500 mg/body wt, n = 6), the increase in serum AST (aspartate aminotransferase) and ALT (alanine aminotransferase) levels were inhibited significantly (P < 0.05) by feeding a diet containing 5% dried BF. Moreover, the BF-administered rat group showed lower concentrations of blood urea nitrogen and a larger amount of urine as compared with values in the control group. Pretreatment of primary cell cultures of rat hepatic and renal cells with BF prior to exposure to dichromate (K2Cr2O7) resulted in a marked decrease of dichromate-induced cytotoxicity as evaluated by the leakage of lactate dehydrogenase The levels of dichromate-induced lipid peroxidation, as monitored by malondialdehyde formation, were also reduced by pretreatment of hepatocytes with BF. These results suggest that BF may play a role in hepatic and renal disorders, and may be useful for maintaining health in humans as well

    Information-seeking behaviour of community pharmacists during the COVID-19 pandemic: an ecological study

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    [Objective] To evaluate the information-seeking behaviour of pharmacists during the COVID-19 pandemic and its relation to COVID-19 and related infections and deaths within the local prefecture. [Design] Ecological study. [Setting] Japan—47 prefectures. [Methods] The number of accesses to a Japanese web page established by the Pharmacy Informatics Group to disseminate information about infection control and the number of infections and deaths in 47 prefectures were investigated from 6 April to 30 September 2020 using the access information on the web page and publicly available information. [Results] During the first 6 months of the COVID-19 pandemic, the total number of accesses was 226 130 (range: 10 984–138 898 per month), the total number of infections was 78 761 (1738–31 857) and the total number of deaths was 1470 (39–436). The correlation between the total number of accesses and that of infections per 100 000 individuals in 47 prefectures was r=0.72 (95% CI 0.55 to 0.83, p<0.001), and between the total number of accesses and deaths per 100 000 individuals in 47 prefectures was r=0.44 (95% CI 0.17 to 0.65, p=0.002). [Conclusions] The information-seeking behaviour of community pharmacists correlated positively with infection status within the community

    Fabrication and Characterization of Element-Doped Perovskite Solar Cells

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    Perovskite solar cells were fabricated and characterized. X-ray diffraction analysis and transmission electron microscopy were used for investigation of the devices. The structure analysis by them showed structural transformation of the crystal structure of the perovskite, which indicated that a cubic-tetragonal crystal system depended on the annealing condition. The photovoltaic properties of the cells also depended on the structures. Metal doping and halogen doping to the perovskite and TiO2 were also investigated. The results showed an increase in the efficiencies of the devices, due to the structural change of the perovskite compound layers
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