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排序方式: 共有409条查询结果,搜索用时 15 毫秒
71.
Cynthia Yuri Ogawa Katsuyuki Hamasaki Shigeki Dan Shuichi Kitada 《Fisheries Science》2011,77(6):915-927
The fishery biology of mud crabs Scylla spp. was examined using baited traps and gill nets from September 2001 to August 2005 at Iriomote Island, Japan. To elucidate
the growth of the crabs, artificially produced S. serrata juveniles were released and recaptured at the study site. The sizes at which 50% of females and males of S. serrata reached sexual maturity (SM50) were estimated as an external carapace width (ECW) based on the morphology of the abdomen and the chela respectively. Two
species, S. serrata and S. olivacea, were identified in the area with S. serrata being the dominant species (>95% of the catch). Changes in the mean ECW and the results of the release and recapture experiments
suggested that the recruitment of young crabs to the fishery occurred from December/January to April/May. The SM50 of females and males occurred at 132.4 and 150.7 mm ECW respectively. The body size composition of S. serrata revealed that immature crabs comprised approximately 40 and 65% of the catch for females and males respectively. To maintain
a sustainable fishery for S. serrata, a minimum landing size based on the SM50 estimates should be implemented as a fishing regulation. 相似文献
72.
Catherine Locke Paramita Muljono Cynthia McDougall Miranda Morgan 《Fish and Fisheries》2017,18(5):943-957
There has so far been limited investigation into gender in relation to innovation in fisheries. Therefore, this study investigates how gender relations shape the capacity and motivation of different individuals in fishing communities to innovate. We compare six fishing communities in Cambodia, the Philippines and the Solomon Islands. Our findings suggest that gendered negotiations mediate the capacity to innovate but that wider structural constraints are important constraints for both men and women. Our findings show that men's and women's capacity to innovate is strongly mediated by the behaviour of their marriage partner. Consequently, we argue that gender research from a social relational perspective has an important contribution to make in understanding poor fishing communities where new ways of doing things or new technologies are being promoted. 相似文献
73.
David M. Peterson Allen D. Budde Cynthia A. Henson Berne L. Jones 《Cereal Chemistry》2001,78(3):349-353
Methods for detecting corn syrup in barley (Hordeum vulgare L.) malt extract were evaluated. Twelve samples representative of commercially available 2‐rowed and 6‐rowed malting barleys were malted. Extracts prepared from the finely ground malts were analyzed for 13C/12C ratios, expressed as δ13C, and concentrations of protein and sugars. The 13C/12C ratios were sufficiently different to distinguish corn syrup from malt extract. By calculating the mean values for the barleys, it was determined that a δ13C > ‐24.3‰ indicated that the malt extract had been adulterated with corn syrup (99% confidence). Protein concentrations <4.5% (2‐rowed malt) or <5.0% (6‐rowed malt) of the extracts also indicated probable adulteration with corn syrup, which is devoid of protein. Because of differences in sugar concentrations between the malt extracts and corn syrup, carbohydrate analysis also indicated probable mixtures. These findings were confirmed by analysis of extracts from composite 2‐rowed and 6‐rowed barley malts that had been mixed with known quantities of corn syrup. The regressions for δ13C, protein concentration, and most sugar concentrations against percent dilution with corn syrup in the mixtures were significant. 相似文献
74.
David L. Straus Cynthia K. Ledbetter David L. Heikes 《Journal of the World Aquaculture Society》2020,51(1):214-223
This study determined the effectiveness of copper sulfate (CuSO4) to inhibit fungal growth (caused by Saprolegnia spp.) on largemouth bass (LMB) eggs spawned on/in fiber mats in very high-alkalinity/-hardness waters; experiments also determined the toxicity of CuSO4 to LMB fry and juveniles. An untreated control and three CuSO4 concentrations (10, 20, and 40 mg/L) were tested under a flow-through scenario in the effectiveness experiment. Eggs were treated daily until hatching began. Fungal load at the time of hatch had a total area > 3.0 cm2 in the untreated controls, total area 1.0 to <2.0 cm2 in the 10 and 20 mg/L CuSO4 treatments, and total area > 1.0 cm2 in the 40 mg/L CuSO4 treatments. Fungus samples were identified as Saprolegnia australis. The 24-hr median lethal concentration (LC50) values on the LMB yolk-sac and swim-up fry were 32.0 and 4.6 mg/L CuSO4, respectively; the No Observed Effect Concentrations (NOEC) were 16.0 and 0.125 mg/L CuSO4, respectively. Juvenile LMB were extremely tolerant to CuSO4, and their 24-hr LC50 value was 185.5 mg/L; the NOEC was 64 mg/L. This study indicates that CuSO4 can be an important resource for hatcheries to control egg fungus, especially in high-alkalinity/-hardness waters. 相似文献
75.
Daniel D. Gallaher Kimberly J. Wood Cynthia M. Gallaher Leonard F. Marquart Alta M. Engstrom 《Cereal Chemistry》1999,76(1):21-24
The intestinal contents viscosities of oat-based breakfast cereals and muffins were examined. Male Sprague-Dawley rats were adapted for four days to a semipurified diet (AIN-76A). Following an overnight fast, the animals were meal-fed 5 g of either the AIN-76A diet (containing 5% cellulose), the AIN-76A diet containing 2% guar gum, whole-grain oat flour, one of five cereals (corn flakes, cooked oatmeal, uncooked oatmeal, cooked oat bran, or Cheerios), or one of two types of muffins (containing whole-grain oat flour or oatmeal). Two hours after presentation of the meal, the animals were killed, the small intestines removed, and the contents collected. The contents were centrifuged, and the viscosity values of the undiluted supernatants were determined. The supernatant viscosity from rats fed the AIN-76A diet was negligible (<5 mPa·sec), whereas that from rats fed guar gum was high (396 ± 117 mPa·sec). Of the cereals fed, corn flakes resulted in the lowest viscosity (<5 mPa·sec). However, all oat-based cereals resulted in high intestinal contents supernatant viscosity levels (cooked oatmeal 368 ± 128, uncooked oatmeal 307 ± 107, cooked oat bran 301 ± 85, Cheerios 199 ± 58, mPa·sec) with no statistically significant differences. The intestinal contents viscosity values for the whole-grain oat flour muffin and oatmeal muffin were 233 ± 52 and 111 ± 26 mPa·sec, respectively, a statistically significant difference (P < 0.05). This suggests that the form of the oat within a food may influence the degree of viscosity produced within the small intestine after that food is consumed. 相似文献
76.
77.
Susceptibility in field populations of codling moth,Cydia pomonella (L.) (Lepidoptera: Tortricidae), in Ontario and Quebec apple orchards to a selection of insecticides 下载免费PDF全文
78.
Sex expression is of primary importance for the genetic improvement and production of monoecious hemp: masculinized phenotypes are associated with higher fungal sensitivity, and feminized phenotypes with higher seed yields. However, sex expression varies quantitatively among plants and nodes and with time. Here, we developed eight variables that characterize the sex expression in monoecious hemp to dissect its genetic determinism. The monoecy degree (MD), ranging from 1 (mostly male flowers) to 5 (mostly female flowers), was recorded for each node of 167 plants, at 6 times at 1‐week intervals. Two types of longitudinal variables were constructed: ‘synthesis’ (mean MD and percentages of nodes of each MD) and ‘structure’. The latter consisted of the parameters of a logistic curve describing MD as a function of the node position. An r‐square of 0.97 was obtained between the estimated and observed MD values, and the logistic parameters were weakly correlated with each other and with the synthesis variables. Therefore, we conclude that the present modelling approach is relevant for characterizing the sex expression in monoecious hemp. 相似文献
79.
Gabriele Vaccari Cynthia H. Panagiotidis Cristina Acin Simone Peletto Francis Barillet Pierluigi Acutis Alex Bossers Jan Langeveld Lucien van Keulen Theodoros Sklaviadis Juan J. Badiola Olivier Andr��oletti Martin H. Groschup Umberto Agrimi James Foster Wilfred Goldmann 《Veterinary research》2009,40(5)
Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP. 相似文献
80.