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101.
Detailed studies indicate a superconducting gap in the high-temperature superconductor Bi(2)Sr(2)CaCu(2)O(8). Photoemission measurements with high energy and angle resolution isolate the behavior of a single band as it crosses the Fermi level in both the normal and superconducting states, giving support to the Fermi liquid picture. The magnitude of the gap is 24 millielectron volts.  相似文献   
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The fumigation-respirometric determination of soil biomass was modified to assess the effects of cultivation on the biomass in the upper 5 cm of intact soil samples. We found the method suitable for comparative studies, but not for providing an absolute measure. The soil biomass increased during the growth of a wheat crop and then decreased to an approximately constant amount. The biomass was significantly greater where the soil had been direct-drilled than where it had been ploughed, probably because plant roots were more abundant after direct drilling. The size of the oil biomass in relation to substrate input is discussed.  相似文献   
104.
Simultaneous measurements of vertical accretion from artificial soilmarker horizons and soil elevation change from sedimentation-erosion table(SET) plots were used to evaluate the processes related to soil building infringe, basin, and overwash mangrove forests located in a low-energy lagoonwhich receives minor inputs of terrigenous sediments. Vertical accretionmeasures reflect the contribution of surficial sedimentation (sedimentdeposition and surface root growth). Measures of elevation change reflectnot only the contributions of vertical accretion but also those ofsubsurface processes such as compaction, decomposition and shrink-swell. Thetwo measures were used to calculate amounts of shallow subsidence (accretionminus elevation change) in each mangrove forest. The three forest typesrepresent different accretionary environments. The basin forest was locatedbehind a natural berm. Hydroperiod here was controlled primarily by rainfallrather than tidal exchange, although the basin flooded during extreme tidalevents. Soil accretion here occurred primarily by autochthonous organicmatter inputs, and elevation was controlled by accretion and shrink-swell ofthe substrate apparently related to cycles of flooding-drying and/or rootgrowth-decomposition. This hydrologically-restricted forest did notexperience an accretion or elevation deficit relative to sea-level rise. Thetidally dominated fringe and overwash island forests accreted throughmineral sediment inputs bound in place by plant roots. Filamentous turfalgae played an important role in stabilizing loose muds in the fringeforest where erosion was prevalent. Elevation in these high-energyenvironments was controlled not only by accretion but also by erosion and/orshallow subsidence. The rate of shallow subsidence was consistently3–4 mm y–1 in the fringe and overwash island forests butwas negligible in the basin forest. Hence, the vertical development ofmangrove soils was influenced by both surface and subsurface processes andthe processes controlling soil elevation differed among forest types.The mangrove ecosystem at Rookery Bay has remained stable as sea levelhas risen during the past 70 years. Yet, lead-210 accretion data suggest asubstantial accretion deficit has occurred in the past century (accretionwas 10–20 cm < sea-level rise from 1930 to 1990) in the fringe andisland forests at Rookery Bay. In contrast, our measures of elevation changemostly equalled the estimates of sea-level rise and our short term estimatesof vertial accretion exceeded the estimates by the amount of shallowsubsidence. These data suggest that (1) vertical accretion in this system isdriven by local sea-level rise and shallow subsidence, and (2) the mangroveforests are mostly keeping pace with sea-level rise. Thus, the vulnerabilityof this mangrove ecosystem to sea-level rise is best described in terms ofan elevation deficit (elevation change minus sea-level rise) based on annualmeasures rather than an accretion deficit (accretion minus sea-level rise)based on decadal measures.  相似文献   
105.
Our objective was to compare survival and complication rates of horses undergoing pelvic flexure enterotomy closure with a TA-90 stapler to those with hand-sewn closure. Medical records of horses undergoing pelvic flexure enterotomy between 2001 and 2008 were reviewed. History, clinical signs, surgical findings, surgical techniques, and post-operative complications were recorded. Long-term outcome was established by telephone questionnaire. Of 84 pelvic flexure enterotomies performed, 70 were stapled and 14 were hand-sewn. Seventy-seven horses survived to discharge (91.7%). There were no significant associations between survival and closure technique (P = 0.69). Follow-up was available for 54 horses; 50 survived long-term (93.0%). No statistical significance was identified between long-term survival and closure method (P = 0.39). Forty horses went on to athletic performance (80.0%). TA-90 stapled closure of pelvic flexure enterotomies is a safe technique resulting in survival and complication rates equivalent to those of hand-sewn closure.  相似文献   
106.
Gingival mass lesions developed when cyclosporine was administered for 600 days to a female, 7-year-old, longhaired dachshund diagnosed with intractable immune-mediated hemolytic anemia (IMHA). Histopathology indicated hyperplastic suppurative gingivitis. As the anemia improved, the dosage of cyclosporine A (CsA) was markedly decreased, and the mass lesions decreased in size and disappeared, thus suggesting that the mass lesions were an adverse reaction to CsA.  相似文献   
107.
A survey of the prevalence of Salmonella species infection was conducted on 59 Irish farrow-to-finish pig herds. Faecal samples were collected from the pens of first-stage weaners (growing pigs approximately three to 10 weeks of age), second-stage weaners (approximately 10 to 17 weeks of age) and fatteners, and from the dry sow and farrowing sow houses. The prevalence of infection was estimated to within 5 per cent with a 95 per cent confidence interval. Thirty of the 59 herds were infected, 12 with Salmonella Typhimurium only, eight with Salmonella Derby only and seven with both S Typhimurium and S Derby; serotypes London, Livingstone and Infantis were each isolated from a single herd. Farms in Ireland are assigned to one of three infection categories on the basis of the antibody levels in samples of meat juice taken at slaughter. When a herd was classified as either positive or negative on the basis of the isolation of Salmonella from at least one faecal sample there was no association between the herd's category as determined by meat juice serology and the probability of the isolation of Salmonella from the faecal samples. However, there were differences in prevalence between pigs at different stages of production in herds of different categories. Farrowing sow houses in moderately infected (category 2) herds had significantly lower infection rates (P < or = 0.05) than other herd categories and other stages of production. Pigs from first-stage weaner pens in slightly infected (category 1) herds were more likely to be infected with Salmonella than pigs at any other stage of production or category of herd.  相似文献   
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