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31.
Estimation of habitat suitability for the southern form of the short‐finned pilot whale (Globicephala macrorhynchus) in the North Pacific 下载免费PDF全文
Habitat models were developed from dedicated sighting survey data collected during summers between 1983 and 2006 in the North Pacific Ocean. Our aim was to examine the distribution pattern of the southern form of the short‐finned pilot whale (Globicephala macrorhynchus) in relation to the physical environment. We tested two different types of analytical procedures for habitat estimation: generalized linear models (GLMs) and ecological niche factor analysis (ENFA). The area under the receiver operating characteristic curve and the Boyce index suggested that GLM defined the core habitat well, whereas ENFA estimated the suitable habitat more correctly. These models indicated the core habitat within the subtropical gyre. Among the environmental variables used to construct the habitat models, the temperature at a depth of 200 m contributed most to both GLM and ENFA. This corresponds to the fact that the species mainly feeds on mesopelagic prey and that the axis of the Kuroshio Current, in the northwestern part of the subtropical gyre, is characterized by its temperature at 200 m. Habitat suitability in the coastal waters off southern Japan also correlated with the Kuroshio meander patterns. Thus, the southern form of the short‐finned pilot whale appears to be particularly well adapted to the ecosystem of the North Pacific subtropical gyre. 相似文献
32.
Makoto ANDO 《中国林学(英文版)》2012,14(2):85-91
We studied the impact of stand density and forest floor humus removal on regeneration of Pinus densiflora in a mixed conifer and broad-leaved forest on the Daimonji-Yama Mountain,Kyoto,Japan.Three levels of stand density were set,i.e.,a clear-cut site,a heavily thinned site and a lightly thinned site.In each density treatment,comparisons were carried out between humus removal (A 0 -free)and humus intact(A 0 -intact)subplots.We counted the emergence of sown pine seeds and measured survival and growth of pine seedlings over the next four years.In addition,light conditions and the recovery of understory were monitored.Results show that thinning intensity and humus removal promoted the establishment and growth of seedlings.One exception,however,was that seedling growth was minimal in the heavily thinned A 0 -intact subplots.This was due to a strong response of understory vegetation growth on the treatment combination,which hindered the pine seedling growth.Furthermore,we found that the canopy openness measured at 1.3-m height remained at least 35%for the heavily thinned site in 2008.The results suggest that the removal of the A 0 layer after heavy thinning is the most effective and labor-saving operation for P.densiflora regeneration. 相似文献
33.
Hideomi?AmanoEmail author Makoto?Kakinuma Daniel?A?Coury Haruka?Ohno Takaaki?Hara 《Fisheries Science》2005,71(5):1160-1166
ABSTRACT: To assess the effect of a seaweed mixture on lipid levels in serum as well as platelet aggregation in rats, Eisenia bicyclis ('Arame'), Hizikia fusiformis ('Hijiki') and Undaria pinnatifida sporophylls ('Mekabu'), all brown seaweeds, and Porphyra yezoensis ('Susabinori'), a red seaweed, were powdered and mixed in a ratio of 45:30:20:5 (w/w). When rats were fed a cholesterol-rich diet containing this mixture of seaweeds (9–10% w/w) for 28 days, serum total cholesterol, LDL-cholesterol, free cholesterol, and triglyceride levels declined significantly to 49.7%, 48.1%, 49.0% and 74.8%, respectively, of those of the control. Serum HDL-cholesterol, however, was unchanged. Though activated partial thromboplatin time, prothrombin time, antithrombin III activity, and fibrinogen levels in plasma were unchanged, the maximal ADP- and collagen-induced platelet aggregation decreased significantly to 89.0% and 85.5% control levels, respectively. These results indicate that this mixture of E. bicyclis , H. fusiformis , U. pinnatifida sporophylls, and P. yezoensis , is useful for the prevention of hyperlipidemia and thrombosis in rats. 相似文献
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Tsuboi M Etoh H Kato K Nakatugawa H Kato H Maejima Y Matsumoto G Mori H Hosokawa M Miyashita K Tokuda H Suzuki N Maoka T 《Journal of agricultural and food chemistry》2011,59(19):10572-10578
The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN). 相似文献
36.
Effects of propofol-sevoflurane anesthesia on the maternal and fetal hemodynamics blood gases, and uterine activity in pregnant goats 总被引:2,自引:0,他引:2
Setoyama K Shinzato T Misumi K Fujiki M Sakamoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(10):1075-1081
To determine the effects of propofol and sevoflurane on hemodynamics, acid-base balance and uterine activity in pregnant animals, a prospective experimental study was designed by use of ten pregnant goats. Propofol was intravenously administered at a bolus dose of 5 mg/kg and then infused a rate of 0.3 mg/kg/min for 5 min. Following the induction, the animals were incrementally inhaled 2.7 and 4.1% of end-tidal concentration of sevoflurane each for 30 min, and then recovered. The maternal and fetal heart rate (HR), arterial blood pressure (BP) and acid-base balance, the intrauterine pressure (IUP), and the uterine blood flow (UBF) were measured. Following the pre-anesthetic data, the parameters were measured 7 times throughout the anesthetic and recovering periods. The propofol infusion induced 1.37 times of HR increase and produced decrease in PO(2) and a relevant metabolic acidemia in the mother, with no effect in the fetus. Sevoflurane reduced BP in the fetus from 30 (2.7%) to 60 (4.1%) min of inhalation. The uterine contractions disappeared throughout sevoflurane inhalation, and then recurred within 15 min after the cessation of sevoflurane. Propofol injection increases HR, and induces a moderate hypoxemia and metabolic acidemia associated with the suppressed ventilation for pregnant goats, with less effect on the fetal hemodinamics. Sevoflurane causes minimal change in maternal hemodynamics, but induces significant hypotension in the fetus and reduction of uterine activity. These data may be useful in making anesthetic choices combined with analgesia for Caesarian section in goats. 相似文献
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Effects of amino nitrogen on fermentation parameters by mixed ruminal microbes when energy or nitrogen is limited 总被引:1,自引:0,他引:1
Hiroshi KAJIKAWA Kiyoshi TAJIMA Makoto MITSUMORI Akio TAKENAKA 《Animal Science Journal》2007,78(2):121-128
Ruminal microbes harvested from a ruminally fistulated cow were incubated in simple batch and semicontinuous cultures with NH3‐N or amino‐N on nitrogen‐ or energy‐excess diets in quantity (HN and LN diets, respectively, consisting of timothy hay plus soybean meal, or corn grain), based on evaluation with the National Research Council and Cornell Net Carbohydrate and Protein System models. In a batch culture experiment, supplementation with amino‐N promoted digestion and fermentation in the course of incubation (4–24 h) on both diets, but these effects mostly disappeared when the diets were sufficiently digested (at 48 h). In a semicontinuous culture experiment using Rusitec, no effect of amino‐N was exhibited after sufficient fermentation and digestion, but significant promotion of digestion was shown in the course of incubation on the HN diet, while no such effect was detected on the LN diet. The microbial yield for 24 h did not show a significant difference between the N sources of either of the two diets. These results suggest that the stimulatory effects of amino‐N are diminished when the diets are sufficiently digested after a long retention and incubation, and also that the effectiveness of amino‐N does not require a quantitatively energy‐excess status. 相似文献
39.
Enhancement of photosynthesis and growth of tomato seedlings by forced ventilation within the canopy 总被引:1,自引:0,他引:1
A forced ventilation system that directs airflow upward or downward within a canopy was developed for plant culture in order to enhance photosynthesis and growth of the plant canopy. Tomato seedling canopies including the seedlings, growing medium, and a plastic tray were used for the experiments. In the upward and downward ventilation systems, air flows upward and downward, respectively, within the plant canopy; this is achieved by blowing and drawing air from holes (Ø 6 mm) made in plastic pipes positioned on the surface of the growing medium. A horizontal airflow system was used as a conventional system to compare the performance of the experimental ventilation systems. Using the upward and downward ventilation systems, the effects of air directions and air velocities on the CO2 exchange rate of the tomato seedling canopy and the growth of the seedlings were compared with those observed using the conventional horizontal airflow system. The forced ventilation within the plant canopy enhanced the CO2 exchange rate of the canopy and the dry masses of the seedlings by 1.4–1.5 and 1.2–1.3 times, respectively, as compared to the conventional horizontal airflow. When the leaf area index (LAI) increased from 1.2 to 2.4, there was only a 5% decrease in the CO2 exchange rate per unit leaf area in the downward ventilation system, whereas there was a 20% decrease in the CO2 exchange rate per leaf area in the horizontal airflow system. The coefficient of variation for the dry mass of the seedlings was higher in the downward system than in the other systems. These results demonstrate that forced ventilation within the canopy is an effective technique to enhance the gas exchange of the plant canopy and the consequent plant growth. 相似文献
40.