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131.
Summary Wood samples that had been ball-milled and extracted with dioxane under various conditions were observed in the scanning electron microscope. Ball milling causes not only a reduction in size of the cells and cell walls but also an internal disruption of the particles. The intensity of milling has a larger influence on the particle size than a prolongation of the milling time. A direct relation was established between particle size and the previously determined yield of purified milled wood lignin.Submitted by Erwin-Riesch-Stiftung zur Förderung der wissenschaftlichen Forschung.  相似文献   
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W. Ehlers: Wasser in Boden und Pflanze—Dynamik des Wasserhaushalts als Grundlage von Pflanzenwachstum und Ertrag. Verlag Eugen Ulmer, Stuttgart (Hohenheim), 1996, 272 Seiten, 137 Abb., 26 Tab., 6 Übersichten, 78,‐DM (569,‐ÖS, 71,‐SFr), ISBN 3–8001–4118–3  相似文献   
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A wide and homogenous viticultural area traverses the border between Friuli Venezia Giulia (Italy) and the western part of Slovenia. Despite similar agricultural, climatic and geographical conditions on each side of the border, the management of agricultural activities and, in particular, the organization of phytosanitary campaigns is carried out separately and differently between the two countries incurring a waste of money, time and energy. The project P. Rada (EU Interreg IIIA Italy Slovenia 2000–06) was set up with the aim of establishing a common expert agrometeorological system to evaluate the development of Plasmopara viticola on a territorial scale. The required agrometeorological data are collected by a network of weather stations and spatially interpolated in a grid with a resolution of 500 × 500 m. The spatial dataset obtained is integrated with rainfall images processed by a polarimetric radar located in Fossalon di Grado (Gorizia, Italy). Once the territorial dataset has been completed, data are used to feed two agrometeorological models: SWEB, for the estimation of leaf wetness, and PLASMO for the simulation of grapevine downy mildew. The main output of the system is represented by meteorological (temperature, rainfall, leaf wetness) and epidemiological (total and current number of infections, days for the outbreak of the current infection) maps capable of supplying end users with detailed information useful for planning and management of grapevine protection activity.  相似文献   
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Both cholangiocarcinoma and squamous cell carcinoma of the stomach stratified squamous epithelial portion are rarely found in equine medicine despite being more common in human beings, dogs, and cats. The objective of the present article was to report the simultaneous occurrences of these two types of neoplasias in an 11-year-old mare. Numerous firm, whitish nodules were distributed throughout the liver parenchyma and those protruding over its surface were umbilicated in their appearance. It was verified that the nodules adhered to the peritoneum and omentum, diaphragm, spleen, and stomach serosa compressed the adjacent structures. The stomach stratified squamous epithelial portion, particularly originating in the margo plicatus toward the cardia, was covered by numerous smooth, whitish spherules. Microscopic examination allowed the liver, tumor, and the abdominal implants to be identified as a cholangiocarcinoma, and the stomach neoplasia as a carcinoma of its stratified squamous epithelial portion. Considering this as an uncommon finding, although when considered individually, the presence of a cholangiocarcinoma and a squamous cell carcinoma of the stratified squamous epithelial portion of the equine stomach in the same specimen is worthy of reporting.  相似文献   
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The operation of the Federal Columbia River Power System (FCRPS) has negatively affected threatened and endangered salmonid populations in the Pacific Northwest. Barging Snake River spring Chinook salmon Oncorhynchus tshawytscha through the FCRPS is one effort to mitigate the effect of the hydrosystem on juvenile salmon out-migration. However, little is known about the occurrence and transmission of infectious agents in barged juvenile salmon relative to juvenile salmon that remain in-river to navigate to the ocean. We conducted a survey of hatchery-reared spring Chinook salmon at various points along their out-migration path as they left their natal hatcheries and either migrated in-river or were barged through the FCRPS. Salmon kidneys were screened by polymerase chain reaction for nine pathogens and one family of water molds. Eight pathogens were detected; the most prevalent were Renibacterium salmoninarum and infectious hematopoietic necrosis virus. Species in the family Saprolegniaceae were also commonly detected. Pathogen prevalence was significantly greater in fish that were barged through the FCRPS than in fish left to out-migrate in-river. These results suggest that the transmission of infectious agents to susceptible juvenile salmon occurs during the barging process. Therefore, management activities that reduce pathogen exposure during barging may increase the survival of juvenile Chinook salmon after they are released.  相似文献   
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