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161.
162.
The edaphic environment in the colonies of the common cormorant (Phalacrocorax carbo) was investigated to detect the effects of cormorant's defecation on plants through the soil. Some properties of the soil down to 50 cm depth in the cormorant's colonies in Chikubu Island and Isaki Cape (Lake Biwa, Shiga Pref., Japan), were compared against those of the soil on the outside of the colonies in 1992. On the inside of the colonies, soil acidification over the whole soil layer, which has been considered to accelerate the accumulation of toxic ions such as Al3+, and increase in moisture content at the depth of 5 and 15 cm, which would inhibit the growth of roots, were recognized. Thus, plants in the colonies of the common cormorant were likely to suffer various negative effects through changes in soil environments mainly due to continual supply of faeces onto the ground.  相似文献   
163.
Ishida A  Toma T  M 《Tree physiology》1999,19(7):467-473
Diurnal changes in gas exchange and chlorophyll fluorescence were measured in the top canopy leaves of the tropical rainforest tree species, Macaranga conifera (Zoll.) Muell. Arg. during a drought year. Maximum values of net photosynthetic rate (P(n), 10 &mgr;mol m(-2) s(-1)) and stomatal conductance (g(s), 0.2 mol m(-2) s(-1)) were found in east-facing leaves in early morning. After 1000 h, both P(n) and g(s) decreased. Minimum daytime values of P(n), g(s), and photosystem II (PSII) quantum yield (DeltaF/F(m)') were found in horizontally fixed leaves. At a given electron transport rate through PSII (ETR), P(n) was higher in early morning than at midday, suggesting a high rate of photorespiration at midday. We tested the hypothesis that the effect of low leaf temperature (T(leaf)) on P(n) is significant in the early morning, whereas the effect of low g(s) on P(n) predominates at midday. In the early morning, when T(leaf) was increased from 32 to 38 degrees C by artificial heating, P(n) at a given ETR decreased 29%, suggesting that the low T(leaf) was associated with a high P(n). When T(leaf) at midday was decreased from 37 to 32 degrees C by artificial cooling, P(n) increased 22%, but P(n) at a given ETR was higher in early morning than at midday, even at the same low T(leaf) (32 degrees C). This suggests that the rate of photorespiration was higher at midday than in early morning because low g(s) at midday caused a reduction in leaf intercellular CO(2) concentration. We conclude that low P(n) at midday was the result of both a reduction in the photochemical process and an increase in stomatal limitation.  相似文献   
164.
An epidemiological survey of bovine Setaria collected from the abdominal cavities was performed morphologically on the cattle in Aomori and Kumamoto Prefectures, Japan, between August 2005 and July 2006. Fifty Setaria worms were collected from the cattle in Aomori Prefecture and 847 from those in Kumamoto Prefecture. Of these worms, 35 were identified as Setaria digitata, 14 as S. marshalli, and one as S. labiatopapillosa in Aomori Prefecture, while 816 were identified as S. digitata and 31 as S. marshalli in Kumamoto Prefecture.  相似文献   
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166.
In this study, we analyzed fatty acid and carotenoid composition of fruit tissues, including seed (which are surrounded by a bright red, oily aril) of Momordica cochinchinensis Spreng, known as gac in Vietnam. Carotenoid content was analyzed by reversed-phase HPLC, using a C(30) column and a method separating cis- and trans-isomers of the major carotenoids in this fruit. Mean values obtained in aril tissues were 1342 microg trans-, 204 microg cis-, and 2227 microg total lycopene; 597 microg trans-, 39 microg cis-, and 718 microg total beta-carotene; and 107 microg alpha-carotene/g FW. Mesocarp contained 11 microg trans-, 5 microg cis-beta-carotene/g FW, trace amounts of alpha-carotene, and no lycopene. Gac aril contained 22% fatty acids by weight, composed of 32% oleic, 29% palmitic, and 28% linoleic acids. Seeds contained primarily stearic acid (60.5%), smaller amounts of linoleic (20%), oleic (9%), and palmitic (5-6%) acids, and trace amounts of arachidic, cis-vaccenic, linolenic, and palmitoleic, eicosa-11-enoic acids, and eicosa-13-enoic (in one fruit only) acids.  相似文献   
167.
The effects of freeze damage on the crumb grain and on the underlying gluten fibrils of baked breads were studied using scanning electron microscopy (SEM) and magnetic resonance imaging (MRI). Sweet and white bread doughs were stored at ‐20°C and subjected to freeze‐thaw cycles. SEM images of grain pore walls that were washed with distilled water (20°C) clearly showed that gluten fibrils forming the skeletal framework of pore walls were cut and became coarse and nonuniform strings and that many knots were generated on gluten fibrils from freeze damage. An increase in the number of freeze‐thaw cycles increased both the coarseness of the gluten fibrils and the size of the knots, although the apparent damage was not clearly detected on the crumb grain with MRI.  相似文献   
168.
Fisheries Science - In the present study, we attempted to investigate the effects of temporal seawater experience on subsequent growth and later seawater acclimability in rainbow trout. To...  相似文献   
169.
170.
Feline immunodeficiency virus infection   总被引:22,自引:0,他引:22  
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