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排序方式: 共有204条查询结果,搜索用时 78 毫秒
71.
R. Lombard 《Journal Of Aquatic Food Product Technology》2013,22(2):117-128
A combination of higher pH (pH 8 vs. pH 6 or 7), higher NaCl content (6% vs. 2%), and shorter chain polyphosphates (sodium tripoly- or pyro-phosphate vs. hexametaphosphate, all at 1.6% in the marinade) during tumbling of halibut pieces (uniform size, shape) resulted in greatest marinade uptake and yields following subsequent purge and cook losses. Surface slime formation noted in optimum treatments, likely the result of increased surface extraction of protein, could dictate moderating ionic strength and solution pH as a marketing consideration. Unfrozen (fresh) fish exhibited a greater uptake of marinade than previously frozen fish, but also higher subsequent purge and cook losses such that yields after cooking for the two treatments were similar. Contrary to conventional industry belief, vacuum (9.2 kPa) during tumbling did not affect uptake of marinade. 相似文献
72.
Fabien Cormier John Foulkes Bertrand Hirel David Gouache Yvan Moënne‐Loccoz Jacques Le Gouis 《Plant Breeding》2016,135(3):255-278
Nitrogen fertilizer is the most used nutrient source in modern agriculture and represents significant environmental and production costs. In the meantime, the demand for grain increases and production per area has to increase as new cultivated areas are scarce. In this context, breeding for an efficient use of nitrogen became a major objective. In wheat, nitrogen is required to maintain a photosynthetically active canopy ensuring grain yield and to produce grain storage proteins that are generally needed to maintain a high end‐use quality. This review presents current knowledge of physiological, metabolic and genetic factors influencing nitrogen uptake and utilization in the context of different nitrogen management systems. This includes the role of root system and its interactions with microorganisms, nitrate assimilation and its relationship with photosynthesis as postanthesis remobilization and nitrogen partitioning. Regarding nitrogen‐use efficiency complexity, several physiological avenues for increasing it were discussed and their phenotyping methods were reviewed. Phenotypic and molecular breeding strategies were also reviewed and discussed regarding nitrogen regimes and genetic diversity. 相似文献
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74.
M. K. O’Neill C. C. Shock K. A. Lombard R. F. Heyduck E. B. G. Feibert D. Smeal R. N. Arnold 《Agroforestry Systems》2010,79(3):409-418
The rapid growth rates of hybrid poplar (Populus spp.) enable rotations of 3–6 years for biofuels or 10–15 years to obtain merchantable timber, but many clones are susceptible
to nutrient deficiencies when grown in alkaline soils. A 1995 Oregon study demonstrated that clone OP-367 (P. deltoides × P. nigra) was the only clone tested that performed well on alkaline soils. Tests in Colorado and New Mexico confirmed the adaptation
of this clone. A multi-clonal trial was established in 2003 at Farmington, New Mexico and Ontario, Oregon in order to screen
a larger number of clones for adaptability to alkaline soils. Trees were planted at 1.5 × 1.5 m spacing and irrigated by surface
drip irrigation. Diameter at breast height (DBH) and tree height were recorded annually (2003–2006); wood volumes (WVol) and
total aboveground biomass (TAB) were calculated from these measurements. Of the 25 clones tested, 19 were common to both sites.
Mean height was greater at the Ontario site through the first 3 years (2003–2005). By the end of four seasons, the tallest
Farmington entry was OP-367 at 9.4 m with 177 Mg ha−1 TAB while the tallest Ontario entry was Malheur-3 at 8.9 m with 195 Mg ha−1 TAB and several other clones had statistically similar production. Given the growth and productivity range at these two sites,
it is difficult to make generalizations across wide areas, but it appears feasible to identify clones suited to alkaline soils
in arid and semi-arid regions. 相似文献
75.
76.
Sandrine Chauchard Fabien Beilhe Nicole Denis Christopher Carcaillet 《Forest Ecology and Management》2010
Global environmental changes observed during recent decades are likely to have had an impact on the distribution of species. Currently, silver fir (Abies alba) is becoming established in the subalpine forests of the west central Alps at elevations higher than 2000 m a.s.l.; prior to the 1970s its upper altitudinal limit was 2000 m. Several hypotheses could explain this recent expansion of the upper tree-limit. Silver fir regeneration could be linked (1) to land-use changes or (2) to current climatic warming. Using dendrochronology, the age structure of 31 forest plots containing at least one silver fir was examined in order to elucidate the population dynamics of subalpine communities. This allowed us to decipher the timing of fir regeneration in relation to the mean age of the stands examined and of the other tree-canopy species present. The majority of the firs germinated sporadically since 1950, before the regional temperature increase. The pattern of fir recruitment did not appear to relate to altitude, but followed a pattern characteristic of secondary succession. The age structures identified showed an exponential increase in tree-density during the 20th century; the stands were first dominated by Larix decidua during the 18th and 19th centuries, and then by Pinus cembra during the 20th century. In most stands, fir regeneration occurred after Larix and before P. cembra dominated, following a similar pattern to Picea abies regeneration. The number of local inhabitants and temperature both exhibited a negative relationship with fir tree recruitment, thus supporting the land-use change hypothesis. There has been a significant upward shift of the altitudinal range of fir, amounting to an increase of about 300 m since 1950. This followed the abandonment of low-productivity land. This trend is likely to continue during the 21st century, because of new agricultural and forestry practices which involve limited intervention in low-productivity areas and may be because of the effects of global warming. 相似文献
77.
Post‐capture survival of whale sharks encircled in tuna purse‐seine nets: tagging and safe release methods
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Lauriane Escalle Hilario Murua Justin Monin Amande Igor Arregui Pierre Chavance Alicia Delgado de Molina Daniel Gaertner Igaratza Fraile John David Filmalter Josu Santiago Fabien Forget Haritz Arrizabalaga Laurent Dagorn Bastien Merigot 《水产资源保护:海洋与淡水生态系统》2016,26(4):782-789
1. Whale shark, the world's largest fish, is believed to be particularly vulnerable owing to its biological characteristics (slow growth, late maturation, great longevity) and is listed as Vulnerable by IUCN and included in Appendix II of CITES. 2. Whale sharks are occasionally encircled in tropical tuna purse‐seine nets, throughout this global fishery. Although apparent immediate survival rates following encirclement and release have recently been assessed through scientific onboard observer programmes, a more rigorous methodology is still required for studying post‐released survival. 3. This work provides a method for applying pop‐up satellite tags and reports an enhanced release procedure for whale sharks. The first assessment of survival after release from purse‐seine nets involved six whale sharks tagged between May and September 2014 in the eastern tropical Atlantic Ocean. Five tags transmitted data: three popped up as programmed (after 30 days), while two surfaced prematurely (one after 21 and the other after 71 days (programmed to pop off after 30 and 90 days, respectively)) but showed no sign of unusual behaviour. 4. Overall, whale sharks survived at least 21 days (one at least 71 days) after release from purse‐seine nets. These observations based on five large individuals (total length > 8 m), suggest that whale sharks have a good chance of survival when released with the proposed method. 5. Additional tagging in this and other oceans, especially of juveniles which may be more sensitive to encirclement and release operations, is essential to further assess whale shark post‐release survival rates in tuna purse‐seine fisheries. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
78.
Alexandra Imhasly Peter R. Tschudi Christoph W. Lombard Vincent Gerber 《Veterinary journal (London, England : 1997)》2010,183(2):166-171
The clinical and echocardiographic characteristics of 108 horses with echocardiographically confirmed mild mitral valve regurgitation (MR) were investigated along with its clinical progression. Follow-up consisted of a re-examination of 28 horses and questionnaires were used to obtain information on a further 43 cases. Thirty-seven horses with mild MR were lost to follow-up. Horses with mild MR were re-examined between 2 and 9 years (3.8 ± 1.8 years) following first presentation, with mild MR still present and a small, but statistically significant (P = 0.049) increase of left ventricular diameter in end-diastole. These results suggested that mild MR has a good mid-term prognosis in sport and pleasure horses. 相似文献
79.
80.
旋毛虫新生幼虫差减cDNA文库的构建及其步筛选 总被引:3,自引:6,他引:3
利用差减杂交(减法杂交,subtractive hybridization)技术,以旋毛虫新生幼虫(newborn larvae,NBL)的cDNA作为试验方(tester),以肌幼虫+成虫的cDNA作为驱动方(driver),制备新生幼虫差减cDNA,利用T载体构建NBL差减cDNA文库,获克隆株90个,以试验方的差减cDNA第2次PCR产物+未差减cDNA为试验方探针,以驱动方的差减cDNA第2次PCR产物+未差减cDNA为驱动方探针,在NBL差减cDNA文库中初筛NBL的期特异性克隆,获初筛克隆24个。这些初筛斯异性克隆进一步用Southern blot确认鉴定,获直阳性期特异性克隆2个(NBL SSC1,NBL SSC2).DNASIS以及Blaster的分析结果显示,这2个克隆为旋毛虫的2个新基因,其中NBL SSC1编码糖蛋白,NBL SSC2编码丝氨本蛋白酶,本试验为旋毛虫期特异性基困全长序列的调取,分析,鉴定以及强保护性抗原基因的筛选奠定了基础。 相似文献