Electronic Phase Transition of Cesium Metal under High Pressure

The isostructural phase transition of cesium metal, CsII←→CsIII, under pressure is discussed in terms of the crystalline energy as a function of volume. Using the augmented plane wave (APW) method and the quantum defect method, the energy bands are calculated at symmetry points in the Brillouin zone for the ran e of relative volume V/V_0 (V_0 : the volume at normal pressure) from 1.30 to 0.24. As the volume decreases, there appears a pronounced tendency of d-states to fall lower relative to s-states, which rise significantly at V/V_0≤0.6. Besides overall rise of the band energy with decreasing volume, a small humped portion is found at 0.4≤V/V_0≤0.5, this being attributed to the shift of electrons into the vicinity of X. The transition beyond this portion is accompanied by a significant volume change. Thus the CsII←→CsIII transition is interpreted as an electronic one. A calculation using the Green\u27s function method is also carried out and the results are compared with those by the APW method

Complex of human neutrophil elastase with 1/2SLPI

The 1/2SLPI and HNE complex structure was solved at 1.7 Å resolution and compared with the interaction mechanism of elafin

Preparation and Characterization of Deposited Tetraethylorthosilicate-SiO2/SiC MIS Structure

The SiO2 layer was deposited on the 4H-SiC Si face by the thermal decomposition of tetraethylorthosilicate(TEOS) in N2 atmosphere to from MIS diodes. The post deposition annealing was effective to improve the interface properties. The interface state density of the deposited SiO2/SiC MIS structure was estimated to be the order of 1011 cm-2eV-1 by Terman method. The direct nitridation of SiC surface prior to the deposition of the SiO2 layer was effective to reduce the interface state density.ArticleMaterials Science Forum, Vols. 740-742, pp. 805-808 (2013)journal articl

Molecular hydrogen protects chondrocytes from oxidative stress and indirectly alters gene expressions through reducing peroxynitrite derived from nitric oxide

<p>Abstract</p> <p>Background</p> <p>Molecular hydrogen (H₂) functions as an extensive protector against oxidative stress, inflammation and allergic reaction in various biological models and clinical tests; however, its essential mechanisms remain unknown. H₂directly reacts with the strong reactive nitrogen species peroxynitrite (ONOO^-) as well as hydroxyl radicals (•OH), but not with nitric oxide radical (NO•). We hypothesized that one of the H₂functions is caused by reducing cellular ONOO^-, which is generated by the rapid reaction of NO• with superoxides (•O₂^-). To verify this hypothesis, we examined whether H₂could restore cytotoxicity and transcriptional alterations induced by ONOO^-derived from NO• in chondrocytes.</p> <p>Methods</p> <p>We treated cultured chondrocytes from porcine hindlimb cartilage or from rat meniscus fibrecartilage with a donor of NO•, <it>S</it>-nitroso-<it>N</it>-acetylpenicillamine (SNAP) in the presence or absence of H₂. Chondrocyte viability was determined using a LIVE/DEAD Viability/Cytotoxicity Kit. Gene expressions of the matrix proteins of cartilage and the matrix metalloproteinases were analyzed by reverse transcriptase-coupled real-time PCR method.</p> <p>Results</p> <p>SNAP treatment increased the levels of nitrated proteins. H₂decreased the levels of the nitrated proteins, and suppressed chondrocyte death. It is known that the matrix proteins of cartilage (including aggrecan and type II collagen) and matrix metalloproteinases (such as MMP3 and MMP13) are down- and up-regulated by ONOO^-, respectively. H₂restoratively increased the gene expressions of aggrecan and type II collagen in the presence of H₂. Conversely, the gene expressions of MMP3 and MMP13 were restoratively down-regulated with H₂. Thus, H₂acted to restore transcriptional alterations induced by ONOO^-.</p> <p>Conclusions</p> <p>These results imply that one of the functions of H₂exhibits cytoprotective effects and transcriptional alterations through reducing ONOO^-. Moreover, novel pharmacological strategies aimed at selective removal of ONOO^-may represent a powerful method for preventive and therapeutic use of H₂for joint diseases.</p

SO(2,1) Covariant IIB Superalgebra

We propose a type IIB super-Poincare algebra with SO(2,1) covariant central extension. Together with SO(2,1) and SO(9,1) generators, a SO(2,1) triplet (momenta), a Majorana-spinor doublet (supercharges) and a Rarita-Schwinger central charge generate a group, G. We consider a coset G/H where H=(SO(2) x Lorentz), and the SL(2,R) 2-form doublet is obtained by the coset construction. It is shown that U(1) connections, whose strengths are associated with 2-forms, are recognized as coordinates of the enlarged space. We suggest that this is the fundamental algebra governing the superstring theories which explains the IIB SL(2,R) duality and geometrical origin of U(1) fields.Comment: 12 pages, Latex; <[email protected], [email protected], [email protected]

0-kV diffractive imaging using newly developed electron diffraction microscope

a b s t r a c t A new electron diffraction microscope based on a conventional scanning electron microscope (SEM), for obtaining atomic-level resolution images without causing serious damage to the specimen, has been developed. This microscope in the relatively low-voltage region makes it possible to observe specimens at suitable resolution and record diffraction patterns. Using the microscope we accomplished 10-kV diffractive imaging with the iterative phase retrieval and reconstructed the structure of a multi-wall carbon nanotube with its finest feature corresponding to 0.34-nm carbon wall spacing. These results demonstrate the possibility of seamless connection between observing specimens by SEM and obtaining their images at high resolution by diffractive imaging

On the Magnetocrystalline Anisotropy of Iron Selenide Fe_7Se_8

Magnetization measurements along the α- and c-axes of a single crystal of a compound Fe_7Se_8 have been carried out in magnetic fields up to 92 kOe over the temperature range from 4.2° to 300°K, together with magnetic torque measurements on the bc-plane up to 9 kOe. The results of magnetization measurements along the c-axis lead to the magnetocrystalline anisotropy energy of the form, E(θ)=-K_0|cosθ|+K_3 cos^2θ+K_4 cos^4θ, the last term being for minor correction. In this expression θ is an angle between magnetization and field direction. The measured values of anisotropy constants K_0 and K_3 at 290°, 77° and 4.2°K are K_0=0.3×10^6, 32×10^6 and 65×10^6 erg/cc and K_3=2.5×10^6, 18×10^6 and 35×10^6 erg/cc, respectively. From the magnetocrystalline energy mentioned above, it can be shown that the magnetic moment takes a conical distribution around the c-axis at low temperatures. The results of torque measurements on the bc-plane is reproduced by assuming a triad crystal domain structure

Exercício aeróbico baseado no primeiro limiar ventilatório em pacientes com excesso de peso e doença renal crônica: impacto sobre a capacidade cardiorrespiratória e funcional

INTRODUCTION: Chronic kidney disease (CKD) and obesity are both associated with reduced physical capacity. The potential benefit of aerobic training on physical capacity has been recognized. The exercise intensity can be established using different methods mostly subjective or indirect. Ventilatory threshold (VT) is a direct and objective method that allows prescribing exercise intensity according to individual capacity. OBJECTIVES: To evaluate the impact of aerobic training at VT intensity on cardiopulmonary and functional capacities in CKD patients with excess of body weight. METHODS: Ten CKD patients (eight men, 49.7 ± 10.1 years; BMI 30.4 ± 3.5 kg/m², creatinine clearance 39.4 ± 9.8 mL/min/1.73 m²) underwent training on a treadmill three times per week during 12 weeks. Cardiopulmonary capacity (ergoespirometry), functional capacity and clinical parameters were evaluated. RESULTS: At the end of 12 weeks, VO2PEAK increased by 20%, and the speed at VO2PEAK increased by 16%. The training resulted in improvement in functional capacity tests, such as six-minute walk test (9.2%), two-minute step test (20.3%), arm curl test (16.3%), sit and stand test (35.7%), and time up and go test (15.3%). In addition, a decrease in systolic and diastolic blood pressures was observed despite no change in body weight, sodium intake and antihypertensive medication. CONCLUSION: Aerobic exercise performed at VT intensity improved cardipulmonary and functional capacities of overweight CKD patients. Additional benefit on blood pressure was observed. These results suggest that VT can be effectively applied for prescribing exercise intensity in this particular group of patients.INTRODUÇÃO: O excesso de peso e a doença renal crônica (DRC) estão associados à baixa capacidade cardiorrespiratória (CR) e funcional (CF). Já foi observado que o treinamento aeróbico (TA) melhora a CR e CF. Métodos indiretos e subjetivos são comumente empregados para a prescrição da intensidade do TA. O limiar ventilatório (LV) é um método direto e objetivo que permite prescrever a intensidade do TA de acordo com a capacidade física do paciente. OBJETIVOS: Avaliar o impacto do TA com base na intensidade do LV sobre a CR e CF de pacientes com excesso de peso e portadores de DRC na fase não dialítica. MÉTODOS: Dez pacientes (oito homens; 49 ± 10,1 anos, IMC 30,4 ± 3,5 kg/m² , depuração de creatinina 39,4 ± 9,8 mL/min/1,73m²) foram submetidos à TA 3 vezes por semana durante 12 semanas. CR (ergoespirometria), CF e parâmetros clínicos foram avaliados. RESULTADOS: O TA promoveu aumento de 20% no consumo pico de O2 (VO2PICO), 16% na velocidade alcançada no VO2PICO e melhora em 9,2% na caminhada de seis minutos, 20,3% na marcha estacionária, 35,7% no sentar e levantar, 16,3% na resistência muscular de membro superior e 15,3% no tempo de ir e voltar. A pressão arterial diminuiu sem modificação nos anti-hipertensivos, no peso ou no consumo de sódio. CONCLUSÃO: Os resultados indicam que o TA baseado na intensidade do LV melhora a CR, CF e pressão arterial de pacientes portadores de DRC com excesso de peso. Isso sugere que o TA baseado na intensidade LV é eficaz e pode ser empregado com segurança nesses pacientes.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo (UNIFESP)UNIFESP Fundação Oswaldo RamosUNIFESP, Fundação Oswaldo RamosSciEL