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排序方式: 共有468条查询结果,搜索用时 46 毫秒
461.
Agroforestry Systems - In the original publication of the article, the article title was incorrectly published. 相似文献
462.
Pain E 《Science (New York, N.Y.)》2008,320(5882):1514-1517
463.
464.
Zusammenfassung Es werden verschiedene Methoden zur Resistenzprüfung von Kartoffelknollen gegen den Erreger der Braunf?ule (Phytophthora infestans (Mont.) de Bary) miteinander verglichen. Drei Prüfungen werden mit Knollenscheiben durchgeführt; bei einem Test werden Knollenh?lften
verwendet. Am besten geeignet erscheint ein modifizierter Test nach Lapwood, der auch die Wundreaktion der Knollen in die
Prüfung mit einbezieht. 相似文献
465.
466.
Juteau-Vigier A Atlan S Deleris I Guichard E Souchon I Trelea IC 《Journal of agricultural and food chemistry》2007,55(9):3577-3584
Aroma compound properties in food matrices, such as volatility and diffusivity, have to be determined to understand the effect of composition and structure on aroma release and perception. This work illustrates the use of mass transfer modeling to identify diffusion and partition properties of ethyl hexanoate in water and in carrageenan matrices with various degrees of structure. The comparison of results obtained with a diffusive model to those obtained with a convective model highlights the importance of considering the appropriate transfer mechanism. Modeling of the preliminary experimental steps ensures correct estimation of the conditions for the main aroma release step. The obtained values of partition and diffusion coefficients are in agreement with those found in the literature (either experimentally determined or predicted by theoretical equations) and demonstrate that the structure level of carrageenan matrices has little influence on diffusion properties of ethyl hexanoate (less than 20%). 相似文献
467.
Pablo Brosset Thomas Doniol‐Valcroze Douglas P. Swain Caroline Lehoux Elisabeth Van Beveren Baye C. Mbaye Kim Emond Stphane Plourde 《Fisheries Oceanography》2019,28(1):1-17
The factors affecting herring recruitment are still poorly understood, complicating the prediction of stock dynamics and the choice of operational management strategies. We investigated effects of intrinsic (SSB) and extrinsic factors (physical and biological environments, including competition and predation) on recruitment of the spring and fall spawning components of each of the two herring stocks occurring in the Gulf of the St. Lawrence between 1971 and 2014. Effects of potential explanatory factors on recruit (age 2) abundance were tested using Generalized Additive Models. Model fit was significantly improved by incorporating both physical and biological environmental variability, but effects of herring SSB and predation were not significant. Indices of zooplankton abundance and phenology explained more variance in recruitment than physical indices. Our results emphasize the dominance of bottom‐up processes over SSB in the regulation of herring recruitment. Environmental variability did not seem to act uniformly on the recruitment of either stock or their respective spawning components. A long‐term trend of decreasing recruitment in spring spawners was associated with a long‐term decline in abundance of cold water copepods. In fall spawners, optimal recruitment was dependent on warmer environmental conditions combined with an adequate supply (species composition and phenology) of zooplankton. These results provide the first empirical evidence that spring and fall spawning herring are adapted to contrasting environmental conditions and shed light on the potential mechanisms linking herring recruitment to key zooplankton community characteristics and phenology. Management strategies can be improved by incorporating this new knowledge on environmental drivers of herring recruitment. 相似文献
468.
Pedersen ME Takle H Ytteborg E Veiseth-Kent E Enersen G Færgestad E Baeverfjord G Hannesson KO 《Fish physiology and biochemistry》2011,37(4):821-831
We have previously characterized the development of vertebral fusions induced by elevated water temperature in Atlantic salmon.
Molecular markers of bone and cartilage development together with histology were used to understand the complex pathology
and mechanism in the development of this spinal malformation. In this study, we wanted to use proteomics, a non-hypothetical
approach to screen for possible new markers involved in the fusion process. Proteins extracted from non-deformed and fused
vertebrae of Atlantic salmon were therefore compared by two-dimensional electrophoresis (2DE) and MALDI-TOF analysis. Data
analysis of protein spots in the 2DE gels demonstrated matrilin-1, also named cartilage matrix protein, to be the most highly
up-regulated protein in fused compared with non-deformed vertebrae. Furthermore, real-time PCR analysis showed strong up-regulation
of matrilin-1 mRNA in fused vertebrae. Immunohistochemistry demonstrated induced matrilin-1 expression in trans-differentiating
cells undergoing a metaplastic shift toward chondrocytes in fusing vertebrae, whereas abundant expression was demonstrated
in cartilaginous tissue and chordocytes of both non-deformed and fused vertebrae. These results identifies matrilin-1 as a
new interesting candidate in the fusion process, and ratify the use of proteomic as a valuable technique to screen for markers
involved in vertebral pathogenesis. 相似文献