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31.
The crystal structure, magnetic properties, and temperature‐ and photoinduced phase transition of [{CoII(4‐methylpyridine)(pyrimidine)}2{CoII(H2O)2}{WV(CN)8}2]·4H2O are described. In this compound, a temperature‐induced phase transition from the CoII (S = 3/2)‐NC‐WV(S = 1/2) [high‐temperature (HT)] phase to the CoIII(S = 0)‐NC‐WIV(S = 0) [low temperature (LT)] phase is observed due to a charge‐transfer‐induced spin transition. When the LT phase is irradiated with 785 nm light, ferromagnetism with a high Curie temperature (TC) of 48 K and a gigantic magnetic coercive field (Hc) of 27 000 Oe are observed. These TC and Hc values are the highest in photoinduced magnetization systems. The LT phase is optically converted to the photoinduced phase, which has a similar valence state as the HT phase due to the optically induced charge‐transfer‐induced spin transition.  相似文献   
32.
An environmental cell for high-temperature, high-resolution transmission electron microscopy of nanomaterials in near atmospheric pressures is developed. The developed environmental cell is a side-entry type with built-in specimen-heating element and micropressure gauge. The relationship between the cell condition and the quality of the transmission electron microscopic (TEM) image and the diffraction pattern was examined experimentally and theoretically. By using the cell consisting of two electron-transparent silicon nitride thin films as the window material, the gas pressure inside the environmental cell is continuously controlled from 10(-5)?Pa to the atmospheric pressure in a high-vacuum TEM specimen chamber. TEM image resolutions of 0.23 and 0.31?nm were obtained using 15-nm-thick silicon nitride film windows with the pressure inside the cell being around 5?×?10(-5) and 1?×?10(4)?Pa, respectively.  相似文献   
33.
Disruption of the skin barrier function caused by epidermal hyper-proliferation, results in the skin becoming dry and showing high transepidermal water loss (TEWL). Gamma linolenic acid (GLA) is reportedly efficacious for treating TEWL and epidermal hyper-proliferation. In this study, to elucidate the effect of GLA-rich oil on skin function, GLA-containing food was given to adults with dry skin or mild atopic dermatitis and skin parameters were evaluated. In the results, we recognized beneficial effects on the TEWL index. The efficacy of GLA was also demonstrated to be statistically significant especially in subjects with pro-inflammatory features. The results suggest that the mechanism of improvement of skin barrier has been associated with possible generation of anti-inflammatory metabolites from GLA. The clinical physician also confirmed that none of the subjects showed any noteworthy side effects. GLA-enriched food appears to be safe and to improve skin barrier function in subjects with dry skin conditions and mild atopic dermatitis.  相似文献   
34.
G protein activation represents an early key event in the complex GPCR signal transduction process and is usually studied by label-dependent methods targeting specific molecular events. However, the constrained environment of such “invasive” techniques could interfere with biological processes. Although histamine receptors (HRs) represent (evolving) drug targets, their signal transduction is not fully understood. To address this issue, we established a non-invasive dynamic mass redistribution (DMR) assay for the human H1–4Rs expressed in HEK cells, showing excellent signal-to-background ratios above 100 for histamine (HIS) and higher than 24 for inverse agonists with pEC50 values consistent with literature. Taking advantage of the integrative nature of the DMR assay, the involvement of endogenous Gαq/11, Gαs, Gα12/13 and Gβγ proteins was explored, pursuing a two-pronged approach, namely that of classical pharmacology (G protein modulators) and that of molecular biology (Gα knock-out HEK cells). We showed that signal transduction of hH1–4Rs occurred mainly, but not exclusively, via their canonical Gα proteins. For example, in addition to Gαi/o, the Gαq/11 protein was proven to contribute to the DMR response of hH3,4Rs. Moreover, the Gα12/13 was identified to be involved in the hH2R mediated signaling pathway. These results are considered as a basis for future investigations on the (patho)physiological role and the pharmacological potential of H1–4Rs.  相似文献   
35.
The Bhas 42 cell transformation assay (Bhas 42 CTA) is the first Organization for Economic Cooperation and Development (OECD)-certificated method used as a specific tool for the detection of the cell-transformation potential of tumor-promoting compounds, including non-genotoxic carcinogens (NGTxCs), as separate from genotoxic carcinogens. This assay offers the great advantage of enabling the phenotypic detection of oncotransformation. A key benefit of using the Bhas 42 CTA in the study of the cell-transformation mechanisms of tumor-promoting compounds, including non-genotoxic carcinogens, is that the cell-transformation potential of the chemical can be detected directly without treatment with a tumor-initiating compound since Bhas 42 cell line was established by transfecting the v-Ha-ras gene into a mouse fibroblast cloned cell line. Here, we analyzed the gene expression over time, using DNA microarrays, in Bhas 42 cells treated with the tumor-promoting compound 12-O-tetradecanoylphorbol-13-acetate (TPA), and NGTxC, with a total of three repeat experiments. This is the first paper to report on gene expression over time during the process of cell transformation with only a tumor-promoting compound. Pathways that were activated or inactivated during the process of cell transformation in the Bhas 42 cells treated with TPA were related not only directly to RAS but also to various pathways in the hallmarks of cancer.  相似文献   
36.
We performed subjective experiments to evaluate color matching performance of the Spectral Properties Estimation Model (SPEM) and six other models (von Kries, CIELAB, LLAB, RLAB, Nayatani, and CIECAM97s) between two CRT monitors whose whites were quite different. Moreover, we evaluated color matching of these models between a CRT monitor and a printed image set in a dark room. The SPEM we developed is a new chromatic adaptation model based on hypothetical spectral properties estimation. This article describes the subjective experiments and the results obtained. The SPEM produced good color matching performance in the experiments. The detailed algorithm of the SPEM is given in the Appendix. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 445–453, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10197  相似文献   
37.
A set of shear-incompatible bicrystals of 48.5 wt pct zinc β-brass was made by diffusion bonding and was then cyclically deformed in tension and compression to study the effect of the grain boundary on the Bauschinger effect. The presence of the secondary stresses near the grain boundary, arising out of compatibility requirements, was confirmed by the increased flow stresses of the bicrystal compared to the single crystal and by the presence of secondary slip systems. The Bauschinger stress in the bicrystals was larger than that in the single crystals, and the amount of the Bauschinger effect depended on the amount of cumulative strain and bicrystal size. It is deduced from extensive slip band observation that the degree of plastic incompatibility compensation by the compatibility slip controls the reverse slip behavior and thus the Bauschinger effect in bicrystals. The Bauschinger effect increases as the degree of incompatibility compensation decreases.  相似文献   
38.
Low‐temperature‐processed inverted perovskite solar cells (PVSCs) attract increasing attention because they can be fabricated on both rigid and flexible substrates. For these devices, hole‐transporting layers (HTLs) play an important role in achieving efficient and stable inverted PVSCs by adjusting the anodic work function, hole extraction, and interfacial charge recombination. Here, the use of a low‐temperature (≤150 °C) solution‐processed ultrathin film of poly[(9,9‐dioctyl‐fluorenyl‐2,7‐diyl)‐co‐(4,4′‐(N‐(4‐secbutylphenyl) diphenylamine)] (TFB) is reported as an HTL in one‐step‐processed CH3NH3PbI3 (MAPbI3)‐based inverted PVSCs. The fabricated device exhibits power conversion efficiency (PCE) as high as 20.2% when measured under AM 1.5 G illumination. This PCE makes them one of the MAPbI3‐based inverted PVSCs that have the highest efficiency reported to date. Moreover, this inverted PVSC also shows good stability, which can retain 90% of its original efficiency after 30 days of storage in ambient air.  相似文献   
39.
The C-terminal boundary of primary sequence of the Bacillussubtilis PAP115 endo-ß-1,4-glucanase (EG) requiredfor stable catalytic activity has been mapped by site-directedmutagenesis using Escherichia coli as host. The 52 kDa cel geneproduct, EG470 and a 33 kDa mutant (EG300), lacking 170 residuesthrough a nonsense mutation at the leucine-330 codon of thegene, exhibited similar patterns of enzymatic activity and pHoptima using cellooligopentaose as substrate.CD spectra indicatedthat the bulk of the -helical secondary structure in EG470 wascontained within EG300. However, relative to EG470, the specificactivity of EG300 was 3- to 4-fold lower with amorphous celluloseas substrate and {small tilde}4-to5-fold higher with carboxymethylcellulose(soluble cellulose).These results along with data which showthat EG470 binding capacity to mirocrystalline cellulose is{small tilde} 11 times more than that of EG300, demonstratethe importance of residues 330–499 for non-catalytic bindingof cellulose. A construct of the cel gene carrying a deletionof codons 330–499 and an insertion of a nonsense codonat leucine-330, was further used to make mutants EG296 and EG291with nonsense codon substitutions at arginine and serine-321,respectively.Western analysis using EG-specific antiserum revealedthat relative losses in enzymatic activity of EG296 (50%) andEG291 (95%) could be accounted for by the extent of their proteolysis,signifying a marked destabilization of these enzymes by removalof only a few amino acids.  相似文献   
40.
A marine microbe (strain SR21) from the coral reef area of the Yap Islands was isolated by a screening test for polyunsaturated fatty acids and was found to accumulate lipid that contained 22:5n-6 docosapentaenoic acid (DPA) as well as 22:6n-3 docosahexaenoic acid (DHA). Strain SR21 was identified as genusSchizochytrium in Labyrinthulomycota, owing to its ultrastructural character and life cycle, which is composed of vegetative cell, zoosporangium, and zoospore stages. After cultural optimization, both in flask and fermenter, the highest DHA and DPA productivities of 2.0 and 0.44 g/L per day, respectively, were obtained in a medium of 60 g/L glucose and corn steep liquor/ammonium sulfate in a half salt concentration of seawater in fermenter culture at 28°C and pH 4. This productivity was almost twice that obtained with flask culture, indicating its high resistance to mechanical stirring. The lipid extracted from the cell was about 50% of the dry cell weight and was composed of 93% triacylglycerol (TG). DHA content of the lipid was 34% of total fatty acids. The TG profile was simple, and the content of the most dominant TG, 1,3-dipalmitoyl-2-DHA-TG, was 27%. TG that contained DHA and n-6-DPA amounted to 57 and 17%, respectively, of total TG molecules. Strain SR21 was revealed to be an excellent source of microbial DHA and n-6 DPA.  相似文献   
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