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排序方式: 共有1100条查询结果,搜索用时 15 毫秒
991.
Robert H. Beach Catherine L. Viator 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1):25-38
One important issue affecting the continued growth and success of the aquaculture industry is risk management. Aquaculture producers face a number of production risks (e.g., weather, disease) that substantially affect their output quantity and quality. Crop insurance is one important potential mechanism for managing these risks, but aquaculture has historically had limited insurance availability in the United States, in part because of unique challenges associated with implementing crop insurance programs in aquatic settings. The Cultivated Clam Pilot Insurance Program, which began in 2000 in four Atlantic Coast states, is the first United States, federal crop insurance program for aquaculture. This program experienced relatively high loss ratios in the early years of the program, but substantial modifications beginning with the 2004 crop year resulted in a significant improvement in actuarial performance. Experiences with clam insurance can provide insight into the potential development and application of insurance programs for other aquaculture products. 相似文献
992.
Ocean's eleven: a critical evaluation of the role of population,evolutionary and molecular genetics in the management of wild fisheries 下载免费PDF全文
Jennifer R Ovenden Oliver Berry David J Welch Rik C Buckworth Catherine M Dichmont 《Fish and Fisheries》2015,16(1):125-159
Significant changes have occurred in the well‐established partnership between fisheries managers and geneticists over the last 50 years. It is therefore timely to review and recalibrate the ways in which genetic technologies can assist the fishing industry to maintain productive and sustainable harvests. Our objective is to contribute to the mutual understanding of all stakeholders in the genetics–management partnership. Genetic technologies that are relevant to fisheries management are grouped into eleven themes, which are described in plain language for a non‐specialist audience. The role that the genetic information plays in fisheries management is explained, along with an assessment of the challenges and barriers that may be preventing the uptake of the information into the fisheries management process. The compelling conclusion is that genetics offers a diverse collection of versatile and useful tools for informing fisheries managers about issues that have a biological basis. Presently, mainstream use of genetic tools focuses on a narrow set of fisheries management issues, but the diversity of genetic tools and the novel issues they can address indicates that uptake will grow, particularly as communication between geneticists and end‐users improves. 相似文献
993.
Natasha C. Moroney Michael N. O’Grady Sinéad Lordan Catherine Stanton Joseph P. Kerry 《Marine drugs》2015,13(4):2447-2464
The anti-oxidative potential of laminarin (L), fucoidan (F) and an L/F seaweed extract was measured using the DPPH free radical scavenging assay, in 25% pork (longissimus thoracis et lumborum (LTL)) homogenates (TBARS) (3 and 6 mg/mL) and in horse heart oxymyoglobin (OxyMb) (0.1 and 1 mg/mL). The DPPH activity of fresh and cooked minced LTL containing L (100 mg/g; L100), F100 and L/F100,300, and bioaccessibility post in vitro digestion (L/F300), was assessed. Theoretical cellular uptake of antioxidant compounds was measured in a transwell Caco-2 cell model. Laminarin displayed no activity and fucoidan reduced lipid oxidation but catalysed OxyMb oxidation. Fucoidan activity was lowered by cooking while the L/F extract displayed moderate thermal stability. A decrease in DPPH antioxidant activity of 44.15% and 36.63%, after 4 and 20 h respectively, indicated theoretical uptake of L/F antioxidant compounds. Results highlight the potential use of seaweed extracts as functional ingredients in pork. 相似文献
994.
Shekhar U. Kadam Colm P. O’Donnell Dilip K. Rai Mohammad B. Hossain Catherine M. Burgess Des Walsh Brijesh K. Tiwari 《Marine drugs》2015,13(7):4270-4280
Ultrasound assisted extraction (UAE), purification, characterization and antioxidant activity of laminarin from Irish brown seaweeds Ascophyllum nodosum and Laminarina hyperborea were investigated. UAE was carried out using 60% ultrasonic power amplitude and 0.1 M hydrochloric acid for 15 min. Separately, solid-liquid extraction was carried in an orbital shaker using 0.1 M hydrochloric acid at 70 °C for 2.5 h. UAE with hydrochloric acid resulted in the highest concentration of laminarin, 5.82% and 6.24% on dry weight basis from A. nodosum and L. hyperborea, respectively. Purification of all extracts was carried out using molecular weight cut off dialysis at 10 kDa. Characterization of the laminarin fraction was carried out using matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Antioxidant activity of A. nodosum and L. hyperborea extracts had 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition levels of 93.23% and 87.57%, respectively. Moreover, these extracts have shown inihibition of bacterial growth of Staphylcoccus aureus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium. 相似文献
995.
Haley C Dewey CE Widowski T Friendship R 《Canadian journal of veterinary research》2010,74(3):178-184
The objective of this study was to determine the association between space allowance and in-transit loss of finishing pigs going to select abattoirs in Ontario during summer weather conditions. The study included data from 2- or 3-tiered trailers transporting ≥ 130 pigs in June, July, and August 2003 to 3 packers that processed 76% of Ontario market pigs. Daily in-transit loss data were merged with packer data to determine the number of pigs on each trailer. Space allowance (in square meters per pig) was estimated from the percentage of each trailer's capacity that was filled by the load size. Actual pig weights were not available. Hourly temperature and relative humidity were obtained from 2 local Ontario weather stations. In-transit loss increased with environmental temperature, by 6.6 times at temperatures between 28°C and 34.2°C compared with < 17°C. At space allowances between 0.44 and 0.43 m(2)/pig compared with ≥ 0.515 m(2)/pig, in-transit losses increased 2.12 times when environmental temperatures were < 21°C. Temperature is likely a more important determinant of in-transit loss than space allowance. However, in-transit losses in hot weather are likely to be reduced by increasing space allowance or by adding a cooling device. 相似文献
996.
Seyedeh Ainaz Shirangi Mohammad Reza Kalbassi Saber Khodabandeh Hojatollah Jafarian Catherine Lorin-Nebel Emilie Farcy Jehan-Hervé Lignot 《Fish physiology and biochemistry》2016,42(6):1741-1754
The effect of abrupt and 5-day gradual salinity transfers from freshwater (FW) to 11 ‰ Caspian Sea brackish water (BW) was investigated in juvenile Persian sturgeon Acipenser persicus with three different weight groups: 1–2 g (1.62 ± 0.27 g), 2–3 g (2.55 ± 0.41 g) and 3–5 g (4.28 ± 0.76 g). Mortality rates, blood osmotic pressure, gill morphology and branchial Na+, K+-ATPase (NKA) activity were measured 4 and 10 days after abrupt transfer and 9 and 15 days after the initial gradual transfer (i.e. 4 and 10 days after reaching Caspian Sea salinity). Fish under 3 g could not survive increased salinity, and the blood osmotic pressure of the remaining surviving fish increased and remained elevated. However, heavier fish were able to survive and successfully acclimate, even to rapid salinity change with osmotic pressure reduced to Caspian Sea osmolality levels. At the gill level, the developmental increase in chloride cell volume and a higher NKA content most probably allow juveniles weighing more than 2 g to sharply increase NKA activity if the fish are transferred to BW. The rapid chloride cell proliferation occurring with increased salinity should strengthen this acclimation response. Therefore, a drastic physiological change occurs when fish weigh more than 2 g that allows migration to higher salinities. The triggering signal on chloride cells must be further investigated in order to optimize this functional step. 相似文献
997.
Yves Barrière Valérie Méchin Cédric Riboulet Sabine Guillaumie Justine Thomas Mickael Bosio Françoise Fabre Deborah Goffner Magalie Pichon Catherine Lapierre Jean-Pierre Martinant 《Euphytica》2009,170(1-2):183-202
Grasses, which are currently at the basis of cattle feeding, will, in the near future, be a major source of cell wall carbohydrates for sustainable biofuel production. The association of lignins with other matrix components, together with linkages between cell wall carbohydrates, greatly influences cell wall properties, including the degradability of structural polysaccharides by micro-organisms in animal rumen or industrial fermenters. The improvement in biofuel production from plants is based on the understanding of the cell wall composition and assembly, and on the discovery of genetic and genomic mechanisms involved in each component biosynthesis and their depositions in each lignified tissue. While nearly 40 QTL have been shown for lignin content, only seven locations appeared of greater importance in investigated genetic resources. Expression studies highlighted that several genes in the lignin pathway are less expressed in lines with higher cell wall degradability. However, only a few lignin pathway genes mapped in QTL positions, and the fully relevant candidates might be genes involved in regulation of lignin pathway genes, or in regulation of lignified tissue assembly. 相似文献
998.
Suzanne M. Owen Carolyn Hull Sieg Catherine A. Gehring Matthew A. Bowker 《Forest Ecology and Management》2009
Mechanical mastication is increasingly prescribed for wildfire mitigation, yet little is known about the ecological impacts of this fuels treatment. Mastication shreds trees into woodchips as an alternative to tree thinning and burning the resulting slash, which can create soil disturbances that favor exotic plants. Previous research on mastication has not simultaneously considered both the responses of soil organisms and understory plant communities. We compared mastication to slash pile burning (both 6-months and 2.5-years post-treatment) and untreated controls in pinyon–juniper (Pinus edulis–Juniperus osteosperma) woodland and measured soil properties, arbuscular mycorrhizal fungi (AMF) and understory plant composition. Our results showed that slash pile burns had severely degraded soil properties and low AMF abundance and richness compared to untreated or mastication plots. Pile burns were dominated by exotic plant species and had approximately 6× less understory plant abundance and richness than untreated plots. Only two variables differed between mastication and untreated plots 6-months post-treatment: mastication had lower soil temperature and higher soil moisture. Mastication plots 2.5-years post-treatment had more plant cover and richness than untreated plots or pile burns, although non-native Bromus tectorum cover was also greater and AMF spore richness was lower than untreated plots. The structural equation model (SEM) we developed showed that plant cover strongly influenced AMF abundance (0.50) and both plant cover (0.36) and AMF (0.31) positively influenced soil stability. In the short-term, mastication is a preferable method as it creates fewer disturbances than pile burning; however long-term impacts of mastication need further study as this practice could affect native plant communities. Our results suggest that the manner in which woody debris is treated following tree thinning has an important influence on soil stability and native plant biodiversity. 相似文献
999.
Patrick Rousset Catherine Lapierre Brigitte Pollet Waldir Quirino Patrick Perre 《Annals of Forest Science》2009,66(1):110-110
1000.
Christophe Plomion Catherine Bastien Marie-Béatrice Bogeat-Triboulot Laurent Bouffier Annabelle Déjardin Sébastien Duplessis Bruno Fady Myriam Heuertz Anne-Laure Le Gac Grégoire Le Provost Valérie Legué Marie-Anne Lelu-Walter Jean-Charles Leplé Stéphane Maury Alexandre Morel Sylvie Oddou-Muratorio Gilles Pilate Léopoldo Sanchez Ivan Scotti Caroline Scotti-Saintagne Vincent Segura Jean-François Trontin Corinne Vacher 《Annals of Forest Science》2016,73(1):77-103