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281.
Lack of exposed ice inside lunar south pole Shackleton Crater 总被引:2,自引:0,他引:2
Haruyama J Ohtake M Matsunaga T Morota T Honda C Yokota Y Pieters CM Hara S Hioki K Saiki K Miyamoto H Iwasaki A Abe M Ogawa Y Takeda H Shirao M Yamaji A Josset JL 《Science (New York, N.Y.)》2008,322(5903):938-939
The inside of Shackleton Crater at the lunar south pole is permanently shadowed; it has been inferred to hold water-ice deposits. The Terrain Camera (TC), a 10-meter-resolution stereo camera onboard the Selenological and Engineering Explorer (SELENE) spacecraft, succeeded in imaging the inside of the crater, which was faintly lit by sunlight scattered from the upper inner wall near the rim. The estimated temperature of the crater floor, based on the crater shape model derived from the TC data, is less than approximately 90 kelvin, cold enough to hold water-ice. However, at the TC's spatial resolution, the derived albedo indicates that exposed relatively pure water-ice deposits are not on the crater floor. Water-ice may be disseminated and mixed with soil over a small percentage of the area or may not exist at all. 相似文献
282.
观察了KT-30与GA_3处理对美味猕猴桃座果、果实发育和品质形成的影响。开花期分别用KT-3040mg·L~(-1)和GA_3500mg·L~(-1)处理花蕾可诱导单性结实;花后20d用KT-3010mg·L~(-1)处理幼果可明显促进果实生长、提高果实中淀粉和糖含量,但降低果实硬度和钙含量且果实外观品质较差。开花后2周用KT-305mg·L~(-1)与GA_3200mg·L~(-1)的混合液处理幼果,可促进果实生长,提高果实硬度,不降低果实外观品质,处理效果最佳。 相似文献
283.
Kon Tatsuya Watanabe Noriko Ootake Hironori Fuji Shin-ichi 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):789-797
European Journal of Plant Pathology - Diseases associated with tomato spotted wilt orthotospovirus (TSWV) are a serious threat to vegetable production worldwide. In 2019, leaf necrosis disease was... 相似文献
284.
Haruna Aiso Futoshi Ishiguri Tatsuya Toyoizumi Yuya Takashima Mineaki Aizawa Shinso Yokota 《Journal of Wood Science》2017,63(3):307-312
The objective of this study is to clarify the relationships between tree sizes and the anatomical, chemical, and physical characteristics of reaction wood. Naturally inclined stems or branches in 23 Japanese angiosperms, including 3 tree sizes at adult trees, 7 arbor, 7 subarbor, and 9 shrub species, were used. The presence of a gelatinous (G-) layer, basic density, vessel frequency, and lignin content were examined on the upper and lower sides of each sample. Almost all the species showed a decrease in vessel frequency and lignin content on the upper side, which are typical characteristics of reaction wood in angiosperms. A G-layer was formed in four arbor, one subarbor, and two shrub species. The ratio of the upper and lower sides in vessel frequency and lignin content gradually decreased with an increase in tree size. Based on the results of the principal component and cluster analyses, shrub species were classified into the different groups: from arbor and subarbor groups. These results indicate that the magnitude of alteration in the characteristics due to reaction wood formation of arbor and subarbor might differ from that of shrub, although the characteristics changed by reaction wood formation might be the same in the three tree sizes at adult trees. 相似文献
285.
Saishu YOSHIDA Hideaki YURINO Masaaki KOBAYASHI Naoto NISHIMURA Kentaro YANO Ken FUJIWARA Shin-ichi HASHIMOTO Takako KATO Yukio KATO 《The Journal of reproduction and development》2022,68(3):225
Pituitary endocrine cells are supplied by Sox2-expressing stem/progenitor cells in the anterior lobe of the adult pituitary gland. These SOX2-positive cells are maintained in two types of microenvironments (niches): the marginal cell layer (MCL)-niche and the parenchymal-niche. Recently, we isolated dense SOX2-positive cell clusters from the parenchymal-niche by taking advantage of their resistance to protease treatment as parenchymal stem/progenitor cell (PS)-clusters. In the present study, by analyzing these isolated PS-clusters, we attempted to identify novel structural characteristics of pituitary stem/progenitor cell niches. Quantitative real-time PCR showed that tight junction-related genes were distinctly expressed in the isolated PS-clusters. Immunocytostaining showed that the tight junction molecules, ZO-1 and occludin, were localized in the apical membrane facing the pseudo-follicle-like structure of the isolated PS-clusters regardless of the expression of S100β, which distinguishes the sub-population of SOX2-positive cells. Furthermore, immunohistochemistry of the pituitary glands of adult rats clearly demonstrated that ZO-1 and occludin were densely present in the parenchymal-niche encircling the pseudo-follicle, while they were observed in the apical membrane in the MCL-niche facing the residual lumen. Collectively, these tight junction-related proteins might be involved in the architecture and maintenance of the plasticity of pituitary stem/progenitor cell niches. 相似文献