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991.
992.
Dubois Mark R. Chappelka Arthur H. Robbins Efrem Somers Greg Baker Karl 《New Forests》2000,20(2):105-118
In the southern USA oaks (Quercusspp.) are often favored by forest owners havingmultiple objectives for forest ownership as oaksprovide mast for wildlife, are consideredaesthetically pleasing, and are valuable for timberproducts. Regeneration and early seedling growth isa concern to those forest owners interested insustaining oaks as a component of their forests. Theeffects of tree shelters and herbaceous weed controlon second-year seedling survival, browse by deer andrabbits, and seedling growth of hand-plantedcherrybark oak (Quercus pagoda Raf.) wereexamined. The study was established on a cutovermixed pine-hardwood forest in Alabama. Fourtreatments were: weed control only, tree shelter only,tree shelter with weed control, and a controlconsisting of a seedling without a tree shelter orweed control. No significant difference in seedlingsurvival was found among the treatments after twoyears. Tree shelters were effective in preventingbrowsing. No seedlings in the tree-shelter-onlytreatment were browsed. There was no significant,difference, however, in the percentage of seedlingsbrowsed between the control treatment and the weedcontrol treatment. The use of tree shelters with weedcontrol was the most effective treatment for promoting2-year ground-line diameter, height, and stem volumegrowth. 相似文献
993.
Margarita Tejada Horst Karl Cristina de las Heras Sanja Vidacek Maria Teresa Solas Maria Luisa Garcia 《Journal Of Aquatic Food Product Technology》2013,22(3):221-236
The distribution of Anisakis larvae in fresh caught hake was studied, and the influence of three infection levels of the viscera (low, medium, high) on quality changes of deep frozen muscle was followed over 220 days. Differences in quality were attributed more to the size of the individuals than to the infection degree of the three groups. The removal of belly flaps diminished the risk of consumers’ infection and sensitization as prevalence and intensity was reduced to 75.6 and 5.9%, respectively. Allergens were detected after 220 days frozen storage, which represents a risk for consumers already allergic to Anisakis. 相似文献
994.
This paper deals with the role of new ideas and actors regarding national level strategy processes and their respective output. Accordingly, the theoretical framework addresses the relation between a policy subsystem's receptiveness to new ideas and actors and the actual presence of new actors and/or new ideas induced by international impulses (independent variables), and the likely influence of the configuration of these factors on strategy processes and their output. Depending on actual subsystem configurations, we deduce four ideal types of strategy processes and outputs (dependent variables): change-oriented, output-oriented, process-oriented and rhetorical strategies.Empirically, we have conducted a comparative analysis of the effects of one legally binding and two non-legally binding international agreements in terms of the changes induced by means of national strategy processes: the Austrian Biodiversity Strategy, the Austrian Forest Dialogue, and the Austrian Strategy for Sustainable Development. These strategies all have their roots in the UNCED Conference in 1992. The respective discourses and agreements introduced new idea sets to national policy processes also promoting participatory, long-term, cross-sectoral and multi-level strategy processes.The empirical analysis confirms effects of the international impulses in terms of introducing new ideas and actors. However, our case studies also point out that the actual effects of similar international impulses for change seem to be systematically mediated by the pre-existing domestic policy subsystem configurations, resulting in substantially different strategy processes and outputs, ranging from quite substantive changes to a mere rhetorical fulfillment of international agreements. 相似文献
995.
Adrian Enache Martin Kühmaier Rien Visser Karl Stampfer 《Scandinavian Journal of Forest Research》2016,31(4):412-427
Timber production is an important ecosystem service of European mountain forests. This paper aimed to assess the current practices in logging operations and to identify the efficiency gaps in timber production. The study was located in 7 case study areas from representative European mountain ranges, where 632 logging operations were analysed. The focus was on road infrastructure, transport systems, harvesting methods and extraction technologies. Often inappropriate technology was used in steep terrain; there was no correlation between the average slope and the selection of harvesting systems (HS). Skidding was the most common extraction method (75%), while cable yarding and forwarding had shares of 15% and 8%. The mean road density was 18.5?m?ha?1. The mean extraction distance was 501?m. The mean harvesting and extraction productivity were 9.0 and 10.2?m³?h?1; the mean costs were 11.1 and 11.7?€?m?³, respectively. Non-mechanized and obsolete HS reported the lowest efficiency and the highest environmental footprint, while fully mechanized systems reported the highest efficiency, the lowest number of accidents and the lowest stand damage. Cable yarders are the appropriate extraction technology in steep terrain, but they require a well-developed road network. Higher mechanization degree, improved quality of the road networks, knowledge transfer to practice and training of forest workers are some of the necessary measures to overcome the efficiency gaps in timber production in European mountain forests. 相似文献
996.
997.
Zetner K Schmidt H Pfeiffer S 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(2):166-171
Concentrations of clindamycin in the mandible were determined in 17 dogs and 13 cats with severe plaque, gingivitis/periodontitis, and calculus that were treated orally with clindamycin (11 mg/kg) once daily for 5 days prior to professional teeth cleaning and extractions. The animals were patients at the Dental Department of the Clinic for Surgery and Ophthalmology of the University of Veterinary Medicine in Vienna, Austria. Clindamycin levels were determined during postextractional alveoloplasty. Approximately 1 to 3 mm3 of mandible was removed from the intraradicular septum in multirooted teeth and from the protruding labial/buccal alveolar rim with a small rongeur. The mean concentration of clindamycin was 8.18 microg/g in dogs (range=3.16 to 24.08 microg/g) and 17.43 microg/g in cats (range=2.45 to 51.60 microg/g). The concentration of clindamycin in the mandibles of dogs and cats may be useful to combat infections after periodontal procedures, tooth extractions, or injuries to the mandible. 相似文献
998.
Karl W. Mueller Wade O. Watanabe William D. Head 《Journal of the World Aquaculture Society》1992,23(3):199-204
Laboratory experiments were conducted to determine the effect of salinity on embryonic development and hatching in Neobenedenia melleni , a monogenean ectoparasite of seawater-cultured (37 ppt) Florida red tilapia ( Oreochromis urolepis hornorum × O. mossambicus ). Eggs, collected from adult monogeneans at 37 ppt, were exposed to different salinities (0, 6, 12, 18, 24, 30 and 37 ppt) for 48, 72 or 96 h. Varying degrees of post-treatment development and hatching occurred when natural seawater conditions were restored. Hatching success generally declined with decreasing salinity and increasing duration of exposure. Under all durations of exposure, hatching success remained relatively high (≥ 69.6%) at salinities of 24 ppt and above, but declined markedly (≤ 32.5%) at lower salinities. Hatching did not occur in eggs exposed to fresh water (0 ppt) for 72 and 96 h. The most effective treatments in preventing hatching, other than prolonged exposure to fresh water, were 96 h exposures to low-salinity brackish water. Percent hatch after 96 h exposure to 6, 12 and 18 ppt was 5.5, 11.9 and 5.8%, respectively. 相似文献
999.
Karl Enigk 《Journal of pest science》1957,30(3):33-34
Ohne Zusammenfassung 相似文献
1000.
Evidence for the Colonization of Lactic Acid Bacteria in the Gastrointestinal Tract of Suckling Mink
Lactic acid bacteria are considered indigenous members of the gastrointestinal microflora in a number of animal species (Savage 1977a). Some intestinal strains of lactobacilli and streptococci are aWe to adhere to stratified squamous epithelium of some animals (Tannock et al. 1987), in the non-secreting part of the stomach of piglets (Barrow et al. 1980, Fuller et al. 1978) and rodents (Tannock et al. 1982), and in the crop of poultry (Fuller 1978). The presence of lactic acid bacteria in the digestive tract is believed to be of beneficial value to the host animal (Fuller 1989). The production of organic acids in the stomach or the crop helps maintaining a low pH which may be important for inhibiting the colonization of potentially pathogenic bacteria, particularly in the newborn animal (Barrow et al 1980, Fuller 1977, Fuller 1978). The adhesion of lactobacilli to squamous epithelium is host specific: strains capable of adhering to the epithelium of piglets are usually not able to adhere in rodents or poultry and vice versa (Fuller 1978, Lin & Savage 1984, Tannock et al 1982). Adhesion of lactic acid bacterial strains to other epithelia than stratified squamous epithelium has been reported. Thus, the attachment of lactobacilli to cells from the secreting epithelium of the murine stomach (Kotarski & Savage 1979), to intestinal cells of humans (Goldin & Gorbach 1987), and to columnar epithelial cells of piglets and calves (Mäyrä-Mäkinen et al 1983) has been demonstrated using in vitro methods. In another study the in vivo attachment of Enterococcus faecium to duodenal epithelium of gnotobi-otic chickens was demonstrated (Fuller et al 1981). Recent research indicated that in adult mink lactic acid bacteria are not indigenous members of the intestinal flora, and they do not attach to epithelium in any part of the gastrointestinal tract (Federsen & Jørgensen 1992). The present paper presents evidence that Gram positive cocci may colonize the gut of suckling mink kits and attach to the gut mucosa. 相似文献