Nitrogen isotopic compositions of some solar-gas-rich chondrites

Isotopically heavy nitrogen was detected in three solar-gas-rich (Weston (H4), ALHA77278 (LL3.7) and Yamato-82133 (H3)) and one solar-gas-poor (LEW86018 (L3.1)) chondrites. Together with a previously studied solar-gas-rich chondrite, all solar-gas-rich chondrites that we examined have isotopically heavy nitrogen. Thus, we suggest that the solar nitrogen is isotopically heavy. The abundance of the heavy nitrogen is, however, not proportional to that of the solar Ne, suggesting complex processing on the surfaces of the parent bodies

Postural muscle activity patterns during standing at rest and on an oscillating floor

金沢大学大学院医学系研究科環境社会医学Postural muscle activity pattern was examined in the eyes-closed state after adequate adaptation to floor anteroposterior oscillation. Twenty-three subjects were grouped almost evenly according to dominance of anterior or posterior postural muscles in the trunk and thigh during quiet stance. In the posterior-dominant group, this dominance was maintained at every frequency in most subjects. In the anterior-dominant group, this dominance was maintained in most subjects at 0.1 and 0.5 Hz but changed to posterior dominance at 1.0 and 1.5 Hz in about half the subjects. Periodicity of muscle activity was evaluated by EMG amplitude spectrum at the floor oscillation frequency. Periodicity of posterior-dominant muscles in the trunk and thigh increased with increasing oscillatory frequency. In the trunk, the periodicity did not differ significantly between posterior-dominant and anterior-dominant groups. However, in the thigh, periodicity was significantly lower in the anterior-dominant muscles. This was considered to be caused by nonperiodic alternating action of the anterior and posterior muscles. In the lower leg, posterior dominance was observed in quiet stance and at all oscillation frequencies. Periodicity of soleus and gastrocnemius increased at higher frequencies and was higher in gastrocnemius than in soleus. The periodicity difference between both muscles decreased with increasing oscillation frequency. © 2005 Elsevier Ltd. All rights reserved

Human Coronavirus 229E Binds to CD13 in Rafts and Enters the Cell through Caveolae

CD13, a receptor for human coronavirus 229E (HCoV-229E), was identified as a major component of the Triton X-100-resistant membrane microdomain in human fibroblasts. The incubation of living fibroblasts with an anti-CD13 antibody on ice gave punctate labeling that was evenly distributed on the cell surface, but raising the temperature to 37°C before fixation caused aggregation of the labeling. The aggregated labeling of CD13 colocalized with caveolin-1 in most cells. The HCoV-229E virus particle showed a binding and redistribution pattern that was similar to that caused by the anti-CD13 antibody: the virus bound to the cell evenly when incubated on ice but became colocalized with caveolin-1 at 37°C; importantly, the virus also caused sequestration of CD13 to the caveolin-1-positive area. Electron microscopy confirmed that HCoV-229E was localized near or at the orifice of caveolae after incubation at 37°C. The depletion of plasmalemmal cholesterol with methyl β-cyclodextrin significantly reduced the HCoV-229E redistribution and subsequent infection. A caveolin-1 knockdown by RNA interference also reduced the HCoV-229E infection considerably. The results indicate that HCoV-229E first binds to CD13 in the Triton X-100-resistant microdomain, then clusters CD13 by cross-linking, and thereby reaches the caveolar region before entering cells

Benzothienobenzothiophene-Based Molecular Conductors: High Conductivity, Large Thermoelectric Power Factor, and One-Dimensional Instability

On the basis of an excellent transistor material, [1]­benzothieno­[3,2-<i>b</i>]­[1]­benzothiophene (BTBT), a series of highly conductive organic metals with the composition of (BTBT)₂XF₆ (X = P, As, Sb, and Ta) are prepared and the structural and physical properties are investigated. The room-temperature conductivity amounts to 4100 S cm^–1 in the AsF₆ salt, corresponding to the drift mobility of 16 cm² V^–1 s^–1. Owing to the high conductivity, this salt shows a thermoelectric power factor of 55–88 μW K^–2 m^–1, which is a large value when this compound is regarded as an organic thermoelectric material. The thermoelectric power and the reflectance spectrum indicate a large bandwidth of 1.4 eV. These salts exhibit an abrupt resistivity jump under 200 K, which turns to an insulating state below 60 K. The paramagnetic spin susceptibility, and the Raman and the IR spectra suggest 4<i>k</i>_F charge-density waves as an origin of the low-temperature insulating state

Benzothienobenzothiophene-Based Molecular Conductors: High Conductivity, Large Thermoelectric Power Factor, and One-Dimensional Instability

On the basis of an excellent transistor material, [1]­benzothieno­[3,2-<i>b</i>]­[1]­benzothiophene (BTBT), a series of highly conductive organic metals with the composition of (BTBT)₂XF₆ (X = P, As, Sb, and Ta) are prepared and the structural and physical properties are investigated. The room-temperature conductivity amounts to 4100 S cm^–1 in the AsF₆ salt, corresponding to the drift mobility of 16 cm² V^–1 s^–1. Owing to the high conductivity, this salt shows a thermoelectric power factor of 55–88 μW K^–2 m^–1, which is a large value when this compound is regarded as an organic thermoelectric material. The thermoelectric power and the reflectance spectrum indicate a large bandwidth of 1.4 eV. These salts exhibit an abrupt resistivity jump under 200 K, which turns to an insulating state below 60 K. The paramagnetic spin susceptibility, and the Raman and the IR spectra suggest 4<i>k</i>_F charge-density waves as an origin of the low-temperature insulating state

Benzothienobenzothiophene-Based Molecular Conductors: High Conductivity, Large Thermoelectric Power Factor, and One-Dimensional Instability

On the basis of an excellent transistor material, [1]­benzothieno­[3,2-<i>b</i>]­[1]­benzothiophene (BTBT), a series of highly conductive organic metals with the composition of (BTBT)₂XF₆ (X = P, As, Sb, and Ta) are prepared and the structural and physical properties are investigated. The room-temperature conductivity amounts to 4100 S cm^–1 in the AsF₆ salt, corresponding to the drift mobility of 16 cm² V^–1 s^–1. Owing to the high conductivity, this salt shows a thermoelectric power factor of 55–88 μW K^–2 m^–1, which is a large value when this compound is regarded as an organic thermoelectric material. The thermoelectric power and the reflectance spectrum indicate a large bandwidth of 1.4 eV. These salts exhibit an abrupt resistivity jump under 200 K, which turns to an insulating state below 60 K. The paramagnetic spin susceptibility, and the Raman and the IR spectra suggest 4<i>k</i>_F charge-density waves as an origin of the low-temperature insulating state