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RD Dr. Edmund Leib 《Journal of pest science》1970,43(8):113-117
Ohne Zusammenfassung 相似文献
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Carbon,nitrogen and phosphorus leaching after site preparation at a boreal forest clear-cut area 总被引:1,自引:0,他引:1
Clear-cutting followed by mechanical site preparation is the major disturbance influencing nutrient and water fluxes in Fennoscandian boreal forests. The effects of soil harrowing on the fluxes of dissolved organic carbon (DOC), dissolved nitrogen compounds (organic N, NH4+ and NO3−) and water soluble phosphorus (PO43−) through a podzolic soil were studied in a clear-cut in eastern Finland for 5 years. The old, mixed coniferous stand was clear-cut and stem only harvested in 1996 followed by soil harrowing in 1998 and planting in June 1999. Zero-tension lysimeters were used to collect soil water from below different soil horizons in the three types of microsites that resulted from site preparation treatment: low ridges (25% of clear-cut area), shallow furrows (30%) and the undisturbed soil (45%). After soil harrowing, the leaching of DOC, N and P from below the B-horizon increased compared to pre-treatment levels. However, the increases were short-lasting; 1–2 years for inorganic N and P, and 5 years for DOC and organic N. The highest concentrations were associated with the ridges and lowest with the furrows, reflecting the differences in amount of organic matter present in each microsite type and, for N, to enhanced mineralization and nitrification. Leaching from below the B-horizon over the 5 years following soil harrowing for the whole clear-cut area was 36.5 kg ha−1 for DOC, 0.88 kg ha−1 for NH4-N, 0.46 kg ha−1 for NO3-N, 1.24 kg ha−1 for organic N and 0.09 kg ha−1 for PO4-P. Site preparation increased temporarily the risk for nutrient leaching into watercourses and groundwater from the clear-cut area but soil fertility was not affected since the leached amounts remained small. The main reasons for the observed low leaching values were the rapid recovery of ground vegetation and low N deposition loads. 相似文献
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Effects of feed ration levels (RLs) and age on sensory characteristics, fillet lipid content (LC) and fatty acid composition (FA) of rainbow trout, Oncorhynchus mykiss (Walbaum), fillet were investigated in a longitudinal feeding experiment. Daily RLs were administered as a percentage of the ration size necessary for expected maximum growth (RL100). Fish on RL50, RL75, RL100 and RL200 were sampled at 1.4, 2.0 and 2.4 years of age. Analyses of LC and FA were carried out on a fillet cross-section. Sensory analyses were performed by an expert panel using ranking and conventional profiling. RL had no effect on the intensity of fresh smell or any sensory characteristic of taste or consistency of fish on RLs over 75%, irrespective of age; fish on RL50, however, scored significantly lower for fresh taste and firmness. Age had no effect on the intensity of total taste, whereas fresh taste increased and rancidity decreased with increasing age irrespective of RL. LC related strongly to RL and age, and increased up to 2.0 years of age. An increase in LC resulted in a higher level of monounsaturated FA and a lower level of polyunsaturated FA. A restriction to RL75 had no negative effects on sensory characteristics, LC or FA of the fillet. 相似文献
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Manuel Martin‐Flores Daniel M Sakai Luis Campoy RD Gleed 《Veterinary anaesthesia and analgesia》2014,41(3):269-277
ObjectiveTo evaluate if return of spontaneous ventilation to pre-relaxation values indicates complete recovery from neuromuscular blockade.Study designProspective, with each individual acting as its own control.AnimalsTen healthy adult female Beagle dogs weighing 6.2–9.4 kg.MethodsDogs were anesthetized with propofol, dexemedetomidine and isoflurane. Spontaneous ventilation was assessed by measuring end-tidal CO2, expired tidal volume, peak inspiratory flow, respiratory rate and minute ventilation. Vecuronium 25 μg kg?1 IV was administered and neuromuscular block was evaluated by measuring the train-of-four (TOF) ratio with acceleromyography in the hind limb. During spontaneous recovery from neuromuscular block, the TOF ratio when each ventilatory variable returned to baseline was recorded.ResultsThis dose of vecuronium produced moderate neuromuscular block in all dogs, with TOF ratio values of 0–18% at maximal block. Expired tidal volume, peak inspiratory flow and minute ventilation returned to pre-relaxation values when the median TOF ratio was ≤ 20%. The median TOF ratio was 42% when the end-tidal CO2 returned to pre-relaxation values.Conclusions and clinical relevanceSignificant residual neuromuscular block could be measured at the hind limb with acceleromyography when ventilation had spontaneously returned to pre-vecuronium values. Monitoring spontaneous ventilation, including end-tidal CO2, expired tidal volume, peak inspiratory flow or minute ventilation cannot be used as a surrogate for objective neuromuscular monitoring, and this practice may increase the risk of postoperative residual paralysis. 相似文献
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Egtved virus: temperature-dependent immune response of trout to infection with low-virulence virus 总被引:1,自引:0,他引:1
P. E. VESTERGÅRD JØRGENSEN 《Journal of fish diseases》1982,5(1):47-55
Abstract. The present report deals with experiments concerning the theoretical basis for development of a live, attenuated vaccine against viral haemorrhagic septicaemia (VHS) of rainbow trout, Salmo gairdneri Richardson, on the basis of a virus strain derived from the Egtved virus reference strain F, the pathogenicity of which has been strongly reduced by in vitro passage. It is shown that the low pathogenicity of the virus (designated the Reva strain) is a genetically stable feature and that the protection against VHS induced by infection with the virus is due to an immune response. Following immunological priming at 10°C partial protection developed at 5° 10° and 15° but not at 20°C, whereas neutralizing antibody was produced at all four temperatures by some of the fish. The duration of virus persistence in trout was found to be inversely proportional to the water temperature. 相似文献
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Trombka JI Squyres SW Bruckner J Boynton WV Reedy RC McCoy TJ Gorenstein P Evans LG Arnold JR Starr RD Nittler LR Murphy ME Mikheeva I McNutt RL McClanahan TP McCartney E Goldsten JO Gold RE Floyd SR Clark PE Burbine TH Bhangoo JS Bailey SH Petaev M 《Science (New York, N.Y.)》2000,289(5487):2101-2105
We report major element composition ratios for regions of the asteroid 433 Eros imaged during two solar flares and quiet sun conditions during the period of May to July 2000. Low aluminum abundances for all regions argue against global differentiation of Eros. Magnesium/silicon, aluminum/silicon, calcium/silicon, and iron/silicon ratios are best interpreted as a relatively primitive, chondritic composition. Marked depletions in sulfur and possible aluminum and calcium depletions, relative to ordinary chondrites, may represent signatures of limited partial melting or impact volatilization. 相似文献