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Shinsuke MORI Akira KAWASAKI Satoru ISHIKAWA Tomohito ARAO 《Soil Science and Plant Nutrition》2009,55(2):294-299
Radioisotope techniques are well known as methods for evaluating symplastic ion absorption in roots. In the present study, a new method for evaluating symplastic cadmium (Cd) absorption in plant roots was developed using the enriched isotopes 113 Cd and 114 Cd. Seedlings of Solanum melongena were exposed to an enriched isotope solution of 113 Cd at 25°C for 30 min. The roots were excised from each seedling and were then immersed in a cold buffer solution without Cd at 2°C for 120 min to suppress the metabolic activity of the roots. Finally, the roots were treated with a cold buffer solution containing enriched stable isotope 114 Cd at 2°C for 120 min, whereby the apoplastically bound 113 Cd was desorbed. We tested the validity of our method for evaluating symplastic Cd in roots compared with the conventional method based on differences in the amount of Cd absorbed at 2°C and 25°C using unlabeled Cd. There was no difference in the symplastic Cd content of the roots between the two methods. These results indicate that it is possible to evaluate the symplastic Cd content in roots using the enriched isotopes 113 Cd and 114 Cd. 相似文献
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Sardine and anchovy regime fluctuations of abundance in four regions of the world oceans: a workshop report 总被引：3，自引：0，他引：3
D. LLUCH-BELDA R. A. SCHWARTZLOSE R. SERRA R. PARRISH T. KAWASAKI D. HEDGECOCK R. J. M. CRAWFORD 《Fisheries Oceanography》1992,1(4):339-347
Regimes of high abundance of sardine (Sardinops sagax and Sardina pilchardus) have alternated with regimes of high abundance of anchovy (Engraulis spp.) in each of the five regions of the world where these taxa co-occur and have been extensively fished. When one taxon has been plentiful, the other has usually been at a reduced level of abundance, and vice versa. Changes in the four heavily fished regions that support S. sagax–the Japanese, Californian, Humboldt, and Benguela systems–from a regime dominated by one taxon to a high level of abundance of the other have occurred more or less simultaneously. In the Pacific Ocean, sardines have tended to increase during periods of increasing global air and sea temperatures and anchovies to decrease. The Japanese system is dominated by sardines to a greater extent than the other systems, and sardines off Japan appear to increase as the Kuroshio Current cools. At the eastern edge of the Pacific Ocean, sardines colonize cooler areas during periods of warming. The Benguela system is out of phase with the three Pacific systems. The four systems all appeared to be in a state of flux in the 1980s. Increased abundance of the subdominant taxon is often one of the first signs of change. Sardines are relatively sedentary in refuge areas when scarce but change behavior to become highly migratory and colonize cooler areas when abundant. Anchovies, by contrast, expand around a fixed geographic center. 相似文献
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A cycle of fluctuation in the Far Eastern sardine, Sardinops sagax, population is accompanied by an abrupt drop and recovery of fish size and lipid content of parent fish, which may reflect a phase variation from coastal to oceanic and its reverse. The cycle begins with the survival success of a smaller number of eggs produced by high-quality parents, which is triggered by a global climate change (density-independent process), and finally ends in the survival failure resulting from an overexpansion of an enormous number of fish produced by low-quality parents (density-dependent process). 相似文献
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Effect of fructo‐oligosaccharides on nutrient digestibility and digesta retention time in adult guinea pigs 
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下载免费PDF全文 A previous study suggested that addition of fructo‐oligosaccharides (FOS) to the diet improved nitrogen (N) utilization and decreased acid detergent fiber (ADF) digestibility in guinea pigs. The present study was conducted to clarify the relationship between ADF digestibility and gastrointestinal mean retention time (MRT) in guinea pigs under FOS supplementation. Adult male guinea pigs were fed a commercial diet (50 g/day) with either 5% glucose (glucose group) or 5% FOS (FOS group) for 12 days in individual metabolism cages. Unlike the glucose group, N utilization improved, but ADF digestibility significantly (P < 0.05) decreased in the FOS group. MRT of solid digesta also significantly (P < 0.05) decreased in the FOS group compared with that in the glucose group. We concluded that reduction of MRT of solid digesta containing FOS decreased ADF digestibility in guinea pigs. 相似文献
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Keratometry in normal cats: a cross-sectional study in Japan using an
automated handheld keratometer
Minae KAWASAKI Tomoya FURUJO Kazuo AZUMA Yoshiharu OKAMOTO Norihiko ITO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(8):1256
Keratometry was performed in 73 domestic cats of varied signalment in Japan using an automated handheld keratometer. The mean corneal curvature radius was significantly lower for cats younger than 1 year than for those older than 2 years (8.04 mm vs. 8.80−8.99 mm, P<0.01). The radius was significantly greater in males than in females among the cats older than 11 years (9.22 mm vs. 8.84 mm, P=0.01), while the age distributions of the males and females were similar. Corneal astigmatism did not significantly differ across the gender and age groups. The predictability of the corneal curvature and astigmatism was approximately 41−43% and less than 3%, respectively, as a function of age and bodyweight. The results highlighted some age- and sex-related keratometric variations in domestic cats in Japan. 相似文献
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We collected 17 milk samples at 1 day to 6 months post partum from one captive okapi (Okapia johnstoni). Milks were examined for nutrient composition, including water, fat, crude protein, carbohydrates, ash and five minerals. The average values of the concentrations were 79.2 ± 3.0% SD water, 8.5 ± 3.4% fat, 7.5 ± 1.1% crude protein, 3.6 ± 0.6% carbohydrate, 1.2 ± 0.1% ash, 263.7 ± 47.3 mg/100 g calcium, 183.0 ± 40.0 mg/100 g phosphorus, 95.2 ± 17.6 mg/100 g sodium, 74.4 ± 34.3 mg/100 g potassium and 28.4 ± 4.4 mg/100 g magnesium, respectively. The protein concentration increased at late lactation (P < 0.01). The contents of sodium and potassium were rather high in the early lactation period, while those of calcium and phosphorus were rather low in the early lactation period. During the course of lactation in the first week post partum and the protein concentration was high at 1 day post partum. We compare our findings with the American Association of Zoos & Aquariums's Okapi Species Survival Plan Hand‐rearing Protocol, and recommend that nutrient composition of the formula for okapi calves is developed using the present study as a guide. 相似文献
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To remove the excess nitrogen and phosphorus in swine wastewater, an electrodialysis technique was applied to an advanced treatment method. The laboratory‐scale swine wastewater treatment system constructed for the present study consisted of an activated sludge process, as the main treatment unit, and electrodialysis, as an advanced treatment unit. This system was operated for 200 days and the processing performance was evaluated. By electrodialysis, approximately 99% of NO3– and PO43– in the activated sludge‐treated water (AT solution) was removed during operation. Furthermore, electrodialysis decreased the color density of the AT solution at a rate of 58%. The advanced treatment of swine wastewater by electrodialysis proved to be an efficient technique to remove excess nitrogen and phosphorus, and decrease color density. 相似文献
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Shengjin WU Motoki NISHIHARA Yoshie KAWASAKI Akitoshi YOKOYAMA Kei MATSUURA Tomohiro KOGA Daisuke UENO Koichi INOUE Takashi SOMEYA 《Soil Science and Plant Nutrition》2009,55(2):258-263
Contamination of agricultural soil by fecal pathogenic bacteria poses a potential risk of infection to humans. For the biosafety control of field soil, soil solarization in an upland field was examined to determine the efficiency of solarization on the inactivation of Escherichia coli inoculated into soil as a model microorganism for human pathogenic bacteria. Soil solarization, carried out by sprinkling water and covering the soil surface with thin plastic sheets, greatly increased the soil temperature. The daily average temperature of the solarized soil was 4–10°C higher than that of the non-solarized soil and fluctuated between 31 and 38°C. The daily highest temperature reached more than 40°C for 8 days in total in the solarized soil during the second and third weeks of the experiment. Escherichia coli in the solarized soil became undetectable (< 0.08 c.f.u. g−1 dry soil) within 4 weeks as a result, whereas E. coli survived for more than 6 weeks in the non-solarized soil. Soil solarization, however, had little influence on the total direct count and total viable count of bacteria in the soil. These results indicate that soil solarization would be useful for the biosafety control of soil contaminated by human pathogens via immature compost or animal feces. 相似文献
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To estimate the effect of fructooligosaccharides (FOS) on N utilization, seven mature rabbits were fed a diet containing 5% glucose or FOS for 8 days. During the last 5 days, total feces and urine were collected to measure N levels (Experiment 1). To examine N transfer from the blood to cecal microbes, eight rabbits were fed the same diets as in Experiment 1. After 9 days of feeding, 2 g of glucose or FOS was given orally. Two hours later 20 mg of 15N‐urea was administered via the ear vein, and 1 h later cecal and blood samples were collected (Experiment 2). Urinary N excretion was lowered by FOS feeding (P < 0.05). Total bacterial N and 15N in the cecum was significantly higher in FOS‐fed animals (P < 0.05). Urea N in the cecum was lower in FOS‐fed rabbits (P < 0.05). Similarly, 15N atom % excess of cecal urea N was also lower in FOS‐fed rabbits than in glucose‐fed rabbits. These results suggest that FOS in the diet increases the transfer of blood urea N to the cecum for bacterial synthesis, thereby increasing N utilization. 相似文献