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471.
We report the direct observation of dioxygen molecules physisorbed in the nanochannels of a microporous copper coordination polymer by the MEM (maximum entropy method)/Rietveld method, using in situ high-resolution synchrotron x-ray powder diffraction measurements. The obtained MEM electron density revealed that van der Waals dimers of physisorbed O2 locate in the middle of nanochannels and form a one-dimensional ladder structure aligned to the host channel structure. The observed O-O stretching Raman band and magnetic susceptibilities are characteristic of the confined O2 molecules in one-dimensional nanochannels of CPL-1 (coordination polymer 1 with pillared layer structure).  相似文献   
472.
Problems caused by water shortage in a paddy-field district with a pipeline network system are different from those in a district with an open channel system. Abnormally low rainfall in Japan caused a very serious water shortage in 1994. A survey was carried out in the Hokuriku region, about 300 km in the north of Tokyo, and a typical paddy cultivation area, to determine problems in irrigation practices caused by water shortage and to find countermeasures for the problems. The following results were obtained. A tank model was proposed to estimate water requirements at the field level. The results showed that the amount of rainfall during the irrigation period in 1994 was only 27.1% of an average year and the rate of water sufficiency at the field level was 70.6%. Then, a simulation method was proposed to estimate hydraulic phenomena in a pipeline network system. The result showed that the pipeline network system distributed water to each hydrant unequally during water shortage. Based on simulations, the methods to equalize water supply to each hydrant and to set up reuse system of water were proposed.  相似文献   
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In this study, we examined the contribution of the cathepsins (cathepsin D and crude cathepsins containing cathepsins B and L) to troponin T degradation during postmortem aging. The action of cathepsin D on troponin T was examined at various pHs (pH 4.0–6.5). The degradation of intact troponin T was observed at pH 4.0, but not observed at pH 5.5 and 6.5. As a result of the degradation of troponin T, the 30 kDa fragment was not generated in any pH condition. The action of the crude cathepsins on troponin T was also examined at various pHs (pH 4.0–6.5). The intact troponin T was degraded at pH 4.0 and the 30 kDa fragments were observed. These 30 kDa fragments disappeared during further incubation. On the other hand, at pH 5.5 and 6.5, the intact troponin T was degraded and the 30 kDa fragment was accumulated. These results suggested that the cathepsin D scarcely contributed to the degradation of troponin T during postmortem aging, but crude cathepsins containing cathepsins B and L were partially involved in the degradation of troponin T and the generation of 30 kDa fragments.  相似文献   
476.
Interactions between tumor and immune cells within the tumor microenvironment play an important role in tumor progression, and small extracellular vesicles (EVs) derived from these tumor cells have been shown to exert immunomodulatory effects on various immune cells, including macrophages and lymphocytes. Although the immunomodulatory effects of small EVs derived from human cancer cells have been intensively investigated, few studies have investigated the effects of lymphoma-derived small EVs on macrophages in both human and veterinary medicine. Here, we evaluated the effects of canine lymphoma-derived small EVs on canine primary monocytes, which are the major source of macrophages in neoplastic tissues. Comprehensive gene expression analysis of these treated monocytes revealed their distinct activation via the Toll-like receptor (TLR) and NF-κβ signaling pathways. In addition, treatment with lymphoma small EVs increased the secretion of MCP-1, which induces the infiltration and migration of monocytes and lymphocytes in neoplastic and cancer tissues. The results of this study indicate that canine lymphoma small EVs activate monocytes, possibly through the activation of TLR and NF-κβ signaling pathways, and induce monocytes to secrete of MCP-1, which might contribute to immune cell infiltration within the tumor microenvironment.  相似文献   
477.
The effect of growing environments of soft wheat on amylose content and its relationship with baking quality and solvent retention capacities (SRC) was investigated. Near‐isogenic soft wheat lines of Norin 61 differing in granule‐bound starch synthase (Wx protein) activity and grown in three different regions of Japan: Hokkaido (spring‐sown) for 2006 and 2007, Kanto (autumn‐sown), and Kyushu (autumn‐sown) for 2007 were evaluated. Spring‐sown samples produced grains of greater protein content (10.9–12.4%) than autumn‐sown samples (7.3–9.1%). In contrast, spring‐sown samples of 2007 with higher maturing temperature had lower amylose content (25.5% for Norin 61) compare to the autumn‐sown and spring‐sown samples of 2006 (27.6–28.4% for Norin 61). Amylose content was strongly correlated to sugar snap cookie (SSCD) diameter (r = 0.957–0.961; n = 10, all samples; P ≤ 0.001, r = 0.701–0.976; n = 7 partial waxy and nonwaxy samples; and Japanese sponge cake (JSCV) volume r = 0.971–0.993; n = 10; P≤ 0.001, r = 0.764–0.922; n = 7 partial waxy and nonwaxy samples), regardless of seeding season and growing conditions. The strength of the JSVC‐amylose relationship (slope) was similar among the three regions, whereas the strength of the SSCD‐amylose relationship was slightly weaker for spring‐sown samples and slightly stronger for partial waxy and nonwaxy autumn‐sown samples. Among of the four solvents (water, solutions of sodium carbonate, sucrose, or lactic acid), water‐SRC showed the greatest correlation to amylose content (r = –0.969 to –0.996; n = 10; P ≤ 0.001, r = –0.629 to –0.983; n = 7 partial waxy and nonwaxy samples), indicated that amylose content can be accurately estimated from the water‐SRC within the samples from the same grown environment.  相似文献   
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