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101.
Udo Tomoko; Bates Marsha E.; Mun Eun Young; Vaschillo Evgeny G.; Vaschillo Bronya; Lehrer Paul; Ray Suchismita 《Canadian Metallurgical Quarterly》2009,23(2):196
Basic mechanisms through which men and women self-regulate arousal have received little attention in human experimental addiction research, although stress-response-dampening and craving theories suggest an important role of emotional arousal in motivating alcohol use. This study examined gender differences in the effects of acute alcohol intoxication on psychophysiological and self-reported arousal in response to emotionally negative, positive, and neutral, and alcohol-related, picture cues. Thirty-six social drinkers (16 women) were randomly assigned to an alcohol, placebo, or control beverage group and exposed to picture cues every 10 s (0.1 Hz presentation frequency). Psychophysiological arousal was assessed via a 0.1-Hz heart rate variability (HRV) index. A statistically significant beverage group-by-gender interaction effect on psychophysiological, but not self-reported, arousal was found. The 0.1-Hz HRV responses to picture cues were suppressed by alcohol only in men. This gender-specific suppression pattern did not differ significantly across picture cue types. There were no significant gender differences in the placebo or control group. Greater dampening of arousal by alcohol intoxication in men, compared with women, may contribute to men’s greater tendency to use alcohol to cope with stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Keisuke Ohdaira Kazuhiro Shiba Hiroyuki Takemoto Tomoko Fujiwara Yohei Endo Shogo Nishizaki Young Rae Jang Hideki Matsumura 《Thin solid films》2009,517(12):3472-4461
Amorphous Si (a-Si) films with lower hydrogen contents show better adhesion to glass during flash lamp annealing (FLA). The 2.0 µm-thick a-Si films deposited by plasma-enhanced chemical vapor deposition (PECVD), containing 10% hydrogen, start to peel off even at a lamp irradiance lower than that required for crystallization, whereas a-Si films deposited by catalytic CVD (Cat-CVD) partially adhere even after crystallization. Dehydrogenated Cat-CVD a-Si films show much better adhesion to glass, and are converted to polycrystalline Si (poly-Si) without serious peeling, but are accompanied by the generation of crack-like structures. These facts demonstrate the superiority of as-deposited Cat-CVD a-Si films as a precursor material for micrometer-thick poly-Si formed by FLA. 相似文献
103.
Summary
Static and dynamic light scattering measurements have been made on a sodium salt sample of succinoglycan in 0.01 M aqueous
NaCl at different temperatures between 25 and 75°C where the polysaccharide undergoes a thermally induced change from an ordered
(helical) to disordered conformation with raising temperature T. The weight-average molecular weight M
w, the z-average radius of gyration, and the hydrodynamic radius sharply decrease in a relatively narrow T range (around 55°C) in which the specific rotation was previously found to change sigmoidally with T. In particular, the value of M
w (4.55 × 105) in the ordered state at 25°C is twice as large as that (2.27 × 105) in the disordered state at 75°C, giving decisive evidence that the helical structure of the polysaccharide in aqueous NaCl
is composed of paired chains. It is concluded that this structure is a double-stranded helix and breaks directly into two
disordered chains with increasing T.
Received: 6 July 2001 / Accepted: 24 July 2001 相似文献
104.
Large Magnetovolume Effect Induced by Embedding Ferromagnetic Clusters into Antiferromagnetic Matrix of Cobaltite Perovskite
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Ping Miao Xiaohuan Lin Akihiro Koda Sanghyun Lee Yoshihisa Ishikawa Shuki Torii Masao Yonemura Takashi Mochiku Hajime Sagayama Shinichi Itoh Kazutaka Ikeda Toshiya Otomo Yinxia Wang Ryosuke Kadono Takashi Kamiyama 《Advanced materials (Deerfield Beach, Fla.)》2017,29(27)
Materials that show negative thermal expansion (NTE) have significant industrial merit because they can be used to fabricate composites whose dimensions remain invariant upon heating. In some materials, NTE is concomitant with the spontaneous magnetization due to the magnetovolume effect (MVE). Here the authors report a new class of MVE material; namely, a layered perovskite PrBaCo2O5.5+x (0 ≤ x ≤ 0.41), in which strong NTE [β ≈ ?3.6 × 10?5 K?1 (90–110 K) at x = 0.24] is triggered by embedding ferromagnetic (F) clusters into the antiferromagnetic (AF) matrix. The strongest MVE is found near the boundary between F and AF phases in the phase diagram, indicating the essential role of competition between the F‐clusters and the AF‐matrix. Furthermore, the MVE is not limited to the PrBaCo2O5.5+x but is also observed in the NdBaCo2O5.5+x . The present study provides a new approach to obtaining MVE and offers a path to the design of NTE materials. 相似文献
105.
Hiraku Onishi Tomoko Oosegi Yoshiharu Machida James W. McGinity 《Drug development and industrial pharmacy》2013,39(8):848-854
Chitosan-prednisolone conjugate microspheres (Ch-SP-MS) were prepared, and Eudragit coating was applied in order to efficiently deliver the microspheres and drug to the intestinal disease sites. The Eudragit L100-coated microspheres (Ch-SP-MS/EuL100) were examined for particle characteristics and the release of drug and Ch-SP-MS in different pH media at 37°C. Ch‐SP-MS were spherical, with a mean size of 4.5 μm and prednisolone content of 3.3% (w/w). Ch-SP-MS/EuL100 were fairly spherical, with a mean size of 22. 5 μm and drug content of 0.32% (w/w). At pH 1.2, the release extent was less than 5% even at 48 h, and Eudragit coating tended to suppress the release. In contrast, at pH 6.8 and 7.4, Ch-SP-MS/EuL100 tended to show somewhat faster drug release than Ch-SP-MS. Ch-SP-MS/EuL100 displayed a release extent of 23 and 27% at pH 6.8 and 7.4, respectively. Ch-SP-MS aggregated at pH 1.2, but almost kept their initial size and shape at pH 6.8 and 7.4. Ch-SP-MS/EuL100 almost maintained their original shape and size at pH 1.2, and gradually released Ch-SP-MS at pH 6.8 and 7.4 due to dissolution of the Eudragit layer. Eudragit coating is suggested to be useful to efficiently deliver Ch-SP-MS to the intestinal disease sites. 相似文献
106.
Shin Takasawa Ryogo Shobatake Yoshinori Takeda Tomoko Uchiyama Akiyo Yamauchi Mai Makino Sumiyo Sakuramoto-Tsuchida Keito Asai Hiroyo Ota Asako Itaya-Hironaka 《International journal of molecular sciences》2022,23(11)
Sleep apnea syndrome (SAS), characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia (IH)), is a risk factor for hypertension and insulin resistance. We report a correlation between IH and insulin resistance/diabetes. However, the reason why hypertension is induced by IH is elusive. Here, we investigated the effect of IH on the expression of catecholamine-metabolizing enzymes using an in vitro IH system. Human and mouse neuroblastoma cells (NB-1 and Neuro-2a) were exposed to IH or normoxia for 24 h. Real-time RT-PCR revealed that IH significantly increased the mRNA levels of dopamine β-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) in both NB-1 and Neuro-2a. Western blot showed that the expression of DBH and PNMT in the NB-1 cells was significantly increased by IH. Reporter assays revealed that promoter activities of DBH and PNMT were not increased by IH. The miR-375 level of IH-treated cells was significantly decreased relative to that of normoxia-treated cells. The IH-induced up-regulation of DBH and PNMT was abolished by the introduction of the miR-375 mimic, but not by the control RNA. These results indicate that IH stress increases levels of DBH and PNMT via the inhibition of miR-375-mediated mRNA degradation, potentially playing a role in the emergence of hypertension in SAS patients. 相似文献
107.
Tomoki Uchio Shota Takiguchi Tomonori Koda Akihiro Nishioka 《Polymer Engineering and Science》2020,60(3):558-562
Thermally expandable microcapsules (MCs) are applicable to the foam processing of polypropylene (PP). The purpose of this study is to clarify the influence of processing conditions, such as temperature, shear rate and resin selection, on the behavior of thermally expandable MCs in PP. In this study, MC was added to several types of PP and extrusion foaming was performed. The average diameter of the MCs after processing was calculated to characterize the expansion of PP including MCs. Two types of molecular architecture, homo- and impact-PP, were examined in this study. The expansion behavior could be summarized by the shear viscosity at the extrusion die. Irrespective of the molecular architecture, data were summarized on one curve on a plane that expressed the relation between the shear viscosity and average MC diameter. Shear viscosity is thus an effective parameter to examine base resin selection for MC foaming. POLYM. ENG. SCI., 60:558–562, 2020. © 2020 Society of Plastics Engineers 相似文献
108.
Product packaging is an important element for branding that directly affects product sales. We have developed a method for creating package images that better express brand perception as a way to motivate purchasing behavior and increase sales. The method works by replacing a color that gives an impression different from the brand perception with one that better expresses the brand perception and that is appropriate for the target product. Brand perceptions perceived by consumers were identified by administering a questionnaire to 160 participants. We constructed two databases: a color database of the correspondence between colors and typical adjectives representing various inner emotional states and a feature database for target products. Using these databases, we applied appropriate colors to packaging (except for areas providing information or containing the logo) to express brand perceptions more accurately. We evaluated this method by performing two experiments, one with 96 participants to determine how changing a package color changed the viewer's impression of the product and the other with seven design experts to determine how this method could help them simulate package design. The results revealed that displaying an appropriately revised package image reduced the gap between the brand perception and the impression obtained upon viewing the package image and gave design experts new ideas for package design. 相似文献
109.
Asahiro Morishita Kyoko Oura Tomoko Tadokoro Koji Fujita Joji Tani Tsutomu Masaki 《International journal of molecular sciences》2021,22(7)
The liver is well recognized as a non-immunological visceral organ that is involved in various metabolic activities, nutrient storage, and detoxification. Recently, many studies have demonstrated that resident immune cells in the liver drive various immunological reactions by means of several molecular modulators. Understanding the mechanistic details of interactions between hepatic host immune cells, including Kupffer cells and lymphocytes, and various hepatic pathogens, especially viruses, bacteria, and parasites, is necessary. MicroRNAs (miRNAs), over 2600 of which have been discovered, are small, endogenous, interfering, noncoding RNAs that are predicted to regulate more than 15,000 genes by degrading specific messenger RNAs. Several recent studies have demonstrated that some miRNAs are associated with the immune response to pathogens in the liver. However, the details of the underlying mechanisms of miRNA interference in hepatic host–pathogen interactions still remain elusive. In this review, we summarize the relationship between the immunological interactions of various pathogens and hepatic resident immune cells, as well as the role of miRNAs in the maintenance of liver immunity against pathogens. 相似文献
110.
Manh Tien Tran Yuka Okusha Yunxia Feng Masatoshi Morimatsu Penggong Wei Chiharu Sogawa Takanori Eguchi Tomoko Kadowaki Eiko Sakai Hirohiko Okamura Keiji Naruse Takayuki Tsukuba Kuniaki Okamoto 《International journal of molecular sciences》2020,21(24)
Rab11b, abundantly enriched in endocytic recycling compartments, is required for the establishment of the machinery of vesicle trafficking. Yet, no report has so far characterized the biological function of Rab11b in osteoclastogenesis. Using in vitro model of osteoclasts differentiated from murine macrophages like RAW-D cells or bone marrow-derived macrophages, we elucidated that Rab11b served as an inhibitory regulator of osteoclast differentiation sequentially via (i) abolishing surface abundance of RANK and c-Fms receptors; and (ii) attenuating nuclear factor of activated T-cells c1 (NFATc-1) upstream signaling cascades, following RANKL stimulation. Rab11b was localized in early and late endosomes, Golgi complex, and endoplasmic reticulum; moreover, its overexpression enlarged early and late endosomes. Upon inhibition of lysosomal function by a specific blocker, chloroquine (CLQ), we comprehensively clarified a novel function of lysosomes on mediating proteolytic degradation of c-Fms and RANK surface receptors, drastically ameliorated by Rab11b overexpression in RAW-D cell-derived osteoclasts. These findings highlight the key role of Rab11b as an inhibitor of osteoclastogenesis by directing the transport of c-Fms and RANK surface receptors to lysosomes for degradation via the axis of early endosomes-late endosomes-lysosomes, thereby contributing towards the systemic equilibrium of the bone resorption phase. 相似文献