We examined the effects of dexamethasone (DEX) on the expressions of key proteins concerned with energy metabolism in brown adipocytes during their differentiation in primary culture. Transcripts of ...the uncoupling protein (UCP), lipoprotein lipase (LPL) and CCAAT enhancer binding protein α (C/EBPα) genes were observed in brown adipocytes cultured in the presence of insulin and thyroid hormones but in the absence of DEX. However, the mRNA level of UCP decreased with the culture period after confluence, and significant mRNA encoding type-1 glucose transporter (GLUT1) was detected in brown adipocytes cultured without DEX, whereas type-4 glucose transporter (GLUT4) was predominantly expressed in mature brown adipocytes in vivo. In contrast, DEX added after confluence consistently elevated the mRNA levels of UCP, LPL and C/EBPα, and repressed the level of GLUT1 in a manner synchronized with increase in the level of GLUT4. Therefore, it is concluded that DEX as well as insulin and thyroid hormones is essential for differentiation of brown adipose precursor cells into mature cells that are similar to brown adipocytes in vivo.
We prepared Ag-sheathed Nd system tape by the compression molding powder-in-tube method. Ag sheathed tapes of Nd system superconductors were studied for sample with nominal composition of ...NdBa2Cu3Oy(Nd123). The critical current density of sample apparently depended on the thickness of the tape and temperature gradient, and increased markedly with decreasing the tape thickness. The maximum value of the critical current density of sample reached 2.0×105 A/cm2 at 6.7 K in zero magnetic field for a tape with 0.3 mm thickness and 1.1×104A/cm2 at 77K in zero magnetic field.
HISPEC (High-resolution Infrared Spectrograph for Exoplanet Characterization) is a proposed diffraction-limited spectrograph for the W.M. Keck Observatory, and a pathfinder for the MODHIS facility ...project (Multi-Object Diffraction-limited High-resolution Infrared Spectrograph) on the Thirty Meter Telescope. HISPEC/MODHIS builds on diffraction-limited spectrograph designs which rely on adaptively corrected single-mode fiber feeds. Seeing-limited high-resolution spectrographs, by virtue of the conservation of beam etendue, grow in volume following a D^3 power law (D is the telescope diameter), and are subject to daunting challenges associated with their large size. Diffraction-limited spectrographs fed by single mode fibers are decoupled from the telescope input, and are orders of magnitude more compact and have intrinsically stable line spread functions. Their efficiency is directly proportional to the performance of the adaptive optics (AO) system. AO technologies have matured rapidly over the past two decades and are baselined for future extremely large telescopes. HISPEC/MODHIS will take R>100,000 spectra of a few objects in a 10" field-of-view sampled at the diffraction limit (~10-50 mas), simultaneously from 0.95 to 2.4 microns (y-K). The scientific scope ranges from exoplanet infrared precision radial velocities, spectroscopy of transiting, close-in, and directly imaged exoplanets (atmospheric composition and dynamics, RM effect, spin measurements, Doppler imaging), brown dwarf characterization, stellar physics/chemistry, proto-planetary disk kinematics/composition, Solar system, extragalactic science, and cosmology. HISPEC/MODHIS features a compact, cost-effective design optimized to fully exploit the existing Keck-AO and future TMT-NFIRAOS infrastructures and boost the scientific reach of Keck Observatory and TMT soon after first light.
We present the results of the near-infrared spectroscopy of the Pluto-Charon system, conducted in the K band at two different sub-Earth longitudes. The spatially resolved images resulted in separated ...spectra with a spectral resolution of approximately 530. The spectrum of Charon showed a broad absorption feature at 2 μm during both orbital phases, suggesting a uniform distribution of water ice. In the separated spectrum of Pluto obtained in June, we confirmed the absorption bands of solid methane, carbon monoxide, and nitrogen ices. Additional weak dips have been found at 2.28, 2.32, and 2.40 μm in the spectrum of the opposite side observed in May. In order to examine the carrier of these dips, we performed model calculations of the reflectance of Pluto using Hapke's bidirectional reflectance model for icy intimate mixtures. By adding a small amount of solid ethane into the mixture, we successfully reproduced the dips at 2.28 and 2.315 μm, but the absorption at 2.40 μm is more distinct than that in the observed spectrum.
The partition mechanism of tetracycline in an n-octanol/H2O system was studied by mathematical treatment of the changes in the apparent partition coefficient determined by Colaizzi and Klink (J. ...Pharm. Sci., 58, 1184 (1969)) and by us, and by measuring the spectral properties of tetracycline in organic solvents. Tetracycline exists in a neutral molecular form in n-octanol, so it could be concluded that transfer of tetracycline from an aqueous to an organic phase is governed not by the amount of the zwitterionic form, but by the amount of the neutral molecular form in the aqueous phase. Results showed that the tetracycline molecule itself is hydrophobic, but that the concentration of the neutral molecular species in the aqueous phase is very small. The relationship between the apparent partition coefficient and the three macroscopic ionization constants of tetracycline at a certain pH was also clarified. From this the macroscopic ionization constants were evaluated. The values agreed very well with those determined by potentiometric titration.
The effects of six thiol-specific cross-linker dimaleimides, in which the distance of the two maleimide groups ranged from 7.7 to 16.8 Å, on bovine heart mitochondria were studied at pH 7.2 and 0 °C. ...None of the dimaleimides affected mitochondrial proteins, but they caused significantly specific intermolecular cross-linking of the 30 kDa ADP/ATP carrier in submitochondrial particles. All the cross-links were found to be formed specifically between two Cys56 residues in the first loop facing the matrix, as we observed previously in intermolecular disulfide bridge formation catalyzed by copper o-phenanthroline Majima, E., Ikawa, K., Takeda, M., Hashimoto, M., Shinohara, Y., and Terada, H. (1995) J.Biol. Chem. 270, 29548−29554. The dimerization was dependent on the cross-linking span of the dimaleimides, being maximum with the dimaleimide having a span of about 12 Å. Cross-linking took place in the m-state carrier, but not in the c-state carrier, and inhibited ADP transport via the ADP/ATP carrier. We suggest that a pair of first loops with Cys56 residues in the dimer form of the m-state carrier fluctuates widely with a most probable distance between them of about 12 Å, and that this fluctuation modulates the transport activity of the ADP/ATP carrier.
We present H-band polarized scattered light imagery and JHK high-contrast spectroscopy of the protoplanetary disk around HD 163296 observed with the HiCIAO and SCExAO/CHARIS instruments at Subaru ...Observatory. The polarimetric imagery resolve a broken ring structure surrounding HD 163296 that peaks at a distance along the major axis of 0.65 (66 AU) and extends out to 0.98 (100 AU) along the major axis. Our 2011 H-band data exhibit clear axisymmetry, with the NW- and SE- side of the disk exhibiting similar intensities. Our data are clearly different than 2016 epoch H-band observations from VLT/SPHERE that found a strong 2.7x asymmetry between the NW- and SE-side of the disk. Collectively, these results indicate the presence of time variable, non-azimuthally symmetric illumination of the outer disk. Based on our 3D-MCRT modeling of contemporaneous IR spectroscopic and H-band polarized intensity imagery of the system, we suggest that while the system could plausibly host an inclined inner disk component, such a component is unlikely to be responsible for producing the observed time-dependent azimuthal variations in the outer scattered light disk of the system. While our SCExAO/CHARIS data are sensitive enough to recover the planet candidate identified from NIRC2 in the thermal IR, we fail to detect an object with a corresponding JHK brightness estimated from the atmospheric models of Baraffe et al. 2003. This suggests that the candidate is either fainter in JHK bands than model predictions, possibly due to extinction from the disk or atmospheric dust/clouds, or that it is an artifact of the dataset/data processing. Our SCExAO/CHARIS data lower the IR mass limits for planets inferred at larger stellocentric separations; however, these ALMA-predicted protoplanet candidates are currently still consistent with direct imaging constraints.
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