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71.
In order to evaluate the effects of settings of digital fisheye photography on estimates of relative illuminance (RI) within a forest under low light conditions, we assessed the effectiveness of some estimators, i.e., canopy openness (CO), sky factor (SF), and diffuse transmittance (DIF). The estimates were calculated from digital hemispherical photographs taken with two different exposure settings, i.e., the reference exposure setting and the auto-exposure setting. We also presented a new estimator (%Exposure), which does not require image analysis, and compared it with other estimators calculated from a digital hemispherical photograph using image analysis. The CO, SF, and DIF calculated from digital hemispherical photographs taken with auto-exposure setting were not significantly correlated with RI. However, those calculated from digital hemispherical photographs taken with reference exposure settings were significantly correlated with RI. On the other hand, %Exposure showed a slightly higher correlation with RI compared with the other estimators.  相似文献   
72.
Neuropeptide Y (NPY) and cholecystokinin (CCK) play important roles in regulating appetite in vertebrates, including mammals and fish. Understanding the appetite mechanism is important in aquaculture to improve production performance. The yellowtail Seriola quinqueradiata is one of the most cultured fish in Japan, but little is known about its appetite hormones. In the present study, complementary DNA encoding for NPY was cloned in yellowtail and consists of 604 bp, in which deduced amino acid sequences show high identity to those of other teleosts. In tissue distribution, the npy and cck mRNAs were detected in all examined tissues (whole brain, telencephalon, optic tectum, hypothalamus, cerebellum, pituitary, retina, stomach, pyloric caeca, anterior intestine, liver, and kidney). In the fasting experiment, only npy mRNA expression in the hypothalamus responded to fasting, showing a significantly high value compared with that in control fish. The expression of cck mRNA in the examined tissues did not change with fasting. The npy mRNA expression in the hypothalamus might be involved in feeding regulation in yellowtail.  相似文献   
73.
Feeding experiment was conducted to determine whether fermentation and taurine supplementation of soybean meal (SBM) fed to yellowtail improve growth performance and lipid digestion. Six diets were formulated and designated as SBM, SBM supplemented with taurine (SBM + T), SBM fermented by Bacillus spp. (FSBM1), SBM fermented by Lactobacillus spp. (FSBM2), FSBM2 supplemented with taurine (FSBM2 + T), and fish meal (FM). Yellowtail fingerlings with an initial body weight of 42 g were stocked in 200‐L tanks. The fish were fed, each diet was fed twice daily in two separate tanks for 8 weeks. Results showed that lipid digestibility of the SBM diet was significantly lower than that of the FM diet, but SBM diet lipid digestibility was improved by taurine supplementation and fermentation. Lipase activity in anterior intestinal digesta, lipid contents in liver and muscle, and bile acid concentrations in gallbladder and anterior intestinal digesta were significantly lower in fish fed SBM diet than in fish fed FM diet; these parameters were not significantly different between fish fed SBM + T, FSBM2, FSBM2 + T diets and FM diet. Although taurine supplementation or fermentation improved lipid digestibility compared with FM diet, growth parameters were only improved in the fish fed FSBM2 + T diet, indicating that apart from a lack of taurine, SBM contains other factors responsible for inferior growth of yellowtail. These factors can be partially eliminated by Lactobacillus spp. fermentation.  相似文献   
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76.
Concentrations of plasma glucose, immunoreactive insulin (IRI) and free fatty acid (FFA) and activities of enzymes related to energy metabolism and lactate dehydrogenase (LDH) isoenzyme pattern in plasma and leukocytes were investigated in lactating Holstein cows (dairy cattle) and fattening Japanese Black Wagyu x Holstein steers (beef cattle). IRI concentrations and LDH and malate dehydrogenase (MDH) activities in the plasma of beef cattle were significantly higher than those in dairy cattle. The cytosolic ratio of MDH/LDH activity in the leukocytes of beef cattle was significantly higher than that of dairy cattle. These findings might be associated with the different energy metabolism between dairy and beef cattle.  相似文献   
77.
Relationships between their activities as blast control agents, and their abilities to inhibit mycelial melanisation on a nutrient agar, are described for 103 substituted benzothiazol-2(3H)-ones, benzoxazol-2(3H)-ones, indolin-2-ones, quinolin-2(1H)-ones, 1,2,3,4-tetrahydroquinolin-2-ones, benzo-1,4-thiazin-3(2H)-ones and benz-1,4-oxazin-3(2H)-ones, and some corresponding thiones. Several compounds in the respective series had a high protective activity and an antimelanisation activity against the blast fungus Pyricularia oryzae; furthermore, there was a good correlation in both of these activities, indicating that these compounds belong to the group of melanin biosynthesis inhibitors. Structural similarities of these compounds can be identified as follows: (a) having a benzo-bicyclic ring system; (b) containing a nitrogen atom in one ring at a position alpha to the benzene ring system; and (c) substitution, at the ring nitrogen atom, at the peri position in the aromatic ring relative to the nitrogen atom, and at the position alpha to the nitrogen atom in the ring system, with a double bond such as in carbonyl and thiocarbonyl groups. Among the compounds that have been proposed as melanin biosynthesis inhibitors, the chemical structures of tricyclazole, pyroquilon, 4,5-dihydro-4-methyltetrazolo[1,5-a]quinazolin-5-one (PP-389), [1,2,4]-triazolo[4,3-a]quinoline and 1-methylquinolin-2(1H)-one exhibit the structural similarities described above; however, 4,5,6,7-tetrachlorophthalide, 2,3,4,5,6-pentachlorobenzyl alcohol and N-substituted-2,3,4,5-tetrachloro-6-(hydroxymethyl)benzamides do not have such similarities in their chemical structures.  相似文献   
78.
Six Wagyu (Japanese Black) steers fitted with a ruminal cannula were used in a split‐plot design experiment comprising a 3 × 3 Latin square design (whole plot) and a randomized blocks design (subplot) to determine the effect of the treatment of potato pulp (PP) with urea and the effect of inclusion levels of PP silage in feed supplement on digestibility, ruminal in situ degradation and ruminal fermentation. The whole plot consisted of 20%, 50% and 80% PP silage (dry matter (DM) basis), with PP silage replacing formula feed. The subplot included untreated or 0.5% (on an as‐fed basis) urea‐treated PP. The treatment of PP with urea showed no effect on DM intake and digestibility. The percentage of the rapidly degradable DM fraction of the urea‐treated PP silage was higher (P < 0.01) and the percentage of its slowly degradable DM fraction was lower (P < 0.01) than for the untreated PP silage. Ruminal ammonia concentration was greater (P < 0.01) for steers fed urea‐treated PP silage than that for steers fed the untreated PP silage. The treatment of PP with urea caused a decrease in the molar proportion of acetate and an increase in the proportion of propionate in ruminal fluid after feeding. The rate of DM degradations in hay (linear, P < 0.01) and in PP silage decreased (linear, P < 0.01) as the inclusion level of PP silage increased. Increasing the inclusion level of PP silage in supplement decreased the effective degradability of DM in hay (linear, P < 0.05) and in PP silage (linear, P < 0.05). An increase in the amount of PP silage increased the molar proportion of acetate (linear, P < 0.01) and decreased the butyrate proportion (linear, P < 0.05) in ruminal fluid. The results suggest that urea treatment of PP facilitates microbial access to starch of PP silage in the rumen and that surplus level of PP silage in supplement have adverse effect on ruminal digestion.  相似文献   
79.
Empirical equations to determine the bearing strength have been proposed by many researchers and design standards. Because these equations have been developed mainly based on test results of softwood species, it is a matter of great importance (to ASEAN structural engineers) to verify the applicability of these equations for tropical hardwood species, which are commonly used in many ASEAN countries. In this study, wood specimens of Shorea obtusa (a tropical hardwood species) were used and the bearing test under full-hole confi guration was carried out for fi ve different loading angles to the grain. The bearing stress-embedment curve obtained from the test was approximated by a linear elastic-plastic diagram indicating the initial and fi nal stiffness of the curve. Testing showed that the average bearing strength parallel to the grain was 7.25% lower than the prediction given in Eurocode 5. The bearing strength perpendicular to the grain evaluated based on bearing load at initial cracking was substantially different from any predictions given by previous studies or design standards. It was also found that the bearing strength and initial stiffness from the bearing stress-embedment curve for loading at intermediate angles to the grain could be satisfactorily predicted with Hankinson’s formula.  相似文献   
80.
磷酸铵盐处理人工林木材的燃烧性能   总被引:11,自引:0,他引:11  
利用锥形量热仪对磷酸铵盐处理的人工林杉木、杨木和马尾松木材的燃烧性能进行研究。结果表明 :磷酸铵盐阻燃处理木材的引燃时间与阻燃剂量有关 ,对 3种木材而言 ,阻燃剂量超过 10 0kg·m- 3,木材才不会被点燃 ;磷酸铵盐对降低木材的释热性能效果明显 ,释热速度降低 ,释热总量减少 ,气相燃烧放热降低 ,而且随着阻燃剂量的增加 ,降低程度更加明显 ;经磷酸铵盐阻燃处理 ,木材失重降低 ,这对保证结构外形的稳定性具有重要作用 ;磷酸铵盐阻燃剂的抑烟作用不理想 ,虽然降低了最强发烟过程的强度 ,但是也提高了最弱发烟过程的强度 ,而且随着阻燃剂量的增加 ,发烟量呈增加的趋势 ;在阻燃研究中 ,阻燃剂在木材内分布状态是一个不可忽视的影响因素 ,特别是木材这种非均质性材料 ,阻燃剂分布的不均匀性将会影响材料整体的耐火性能  相似文献   
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