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41.
ABSTRACTAims: To determine the presence of infection and co-infection of Plasmodium lineages in introduced birds at translocation sites for the North Island saddleback (Philesturnus rufusater), to investigate their role as Plasmodium spp. reservoirs.Methods: Blood samples were collected from introduced bird species, with a special focus on blackbirds (Turdus merula) and song thrushes (Turdus philomelos), at six locations in the North Island of New Zealand that were the origin, or translocation sites, for North Island saddleback. Where available, blood smears were examined, and blood samples were tested using nested PCR with subsequent sequence analysis, for the presence of Plasmodium spp.Results: Of the 55 samples tested using PCR analysis, 39 (71%) were positive for Plasmodium spp., and 28/40 (62%) blood smears were positive for Plasmodium spp. Overall, 31 blood samples were from blackbirds with 28/31 (90%) samples positive for Plasmodium spp. Six distinct avian Plasmodium lineages were identified, including three cosmopolitan lineages; Plasmodium vaughani SYAT05 was detected in 16 samples, Plasmodium matutinum Linn1 in 10 samples and Plasmodium elongatum GRW6 in eight samples. Mixed infections with more than one lineage were detected in 12 samples. Samples from two Australian magpies (Gymnorhina tibicen) were positive for Plasmodium. sp. lineage MYNA02, previously not identified in New Zealand.Conclusions and clinical relevance: This is the first report from New Zealand in which specific Plasmodium spp. mixed infections have been found in introduced birds. Co-infections with several cosmopolitan Plasmodium lineages were identified, as well as the first report in New Zealand of an exotic avian Plasmodium sp. lineage, in Australian magpies. Whilst the role of introduced birds in maintaining and spreading pathogenic avian malaria in New Zealand is unclear, there is a potential infection risk to native birds, especially where distributions overlap. 相似文献
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据统计,以我国每年新增的大约10亿m2的商品房建筑面积,加之旧房改造装修大约5亿m2的面积,其中室内门占10%,而各类木质门又为其中的70%的数量计算,几乎潜在有超过1亿m2木门需求的巨大市场. 相似文献
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M. ÍHA J. KUBEKA M. VAEK J. SEA T. MRKVIKA M. PRCHALOVÁ J. MATNA M. HLADÍK M. ECH V. DRATÍK J. FROUZOVÁ E. HOHAUSOVÁ O. JAROLÍM T. JZA M. KRATOCHVÍL J. PETERKA & M. TUER 《Fisheries Management and Ecology》2009,16(2):121-129
Abstract The inshore fish community of the Římov Reservoir in the Czech Republic was evaluated over 21 years using shore seining at night. The development of the fish community was divided into two separate phases: a highly dynamic and unstable phase dominated by perch, Perca fluviatilis L., was replaced by an extremely stable cyprinid phase dominated by roach, Rutilus rutilus (L.), and bream, Abramis brama (L.). The abundance of both these species oscillated during the cyprinid phase, but with decreasing amplitude. The proportion of piscivorous fish species such as asp, Aspius aspius (L.), pike, Esox lucius L., and pikeperch, Sander lucioperca (L.), increased slightly with time but remained low. The biomass of large Cladocera was negatively correlated with fish biomass only during the perch phase. The Shannon–Weaver index of diversity increased during the fish community succession, mainly because of greater evenness amongst the species. 相似文献
44.
【目的】 研究深松结合覆膜滴灌对绿洲棉田根区土环境与根腐病发生的影响。【方法】 在新疆阿克苏地区阿瓦提县设置深松30、40和50 cm(S30、S40和S50)3种深松模式,以传统翻耕为对照(CK),研究深松对根腐病发病指数、土壤含水率、根系形态、根系活力及产量构成等影响。【结果】 与传统耕作相比,深松可有效降低耕层土壤容重,增加土壤储水能力,增加土壤扩库增容效果,病情指数的降低与土壤容重下降、土壤含水率的增加和根系活力增加具有显著的相关性。其中深松降低生育期根腐病发病指数7.0%~26.0%,以S40处理效果最佳,发病指数较传统耕作相比降低26.0%。随着深松深度的增加土壤容重依次下降,与对照相比降低2.4%~10%。深松深度与根系主要形态指标与活力具有线性相关性,与传统耕作相比根系长度增加4%~34.6%,根系表面积增加13.1%~44.8%,根系体积增加9.2%~40.6%,根系活力增加7%~42.9%。根区环境的改善促进产量增加,S40处理皮棉产量分别较CK、S30、S50增加了22.2%、15.7%和2.5%。【结论】 在新疆南疆棉区采用深松结合覆膜滴灌措施具有良好的蓄水保墒和防病增产效果,对棉花生长有利,深松40 cm处理可作为较为理想的根腐病农艺防治措施在生产中推广应用。 相似文献
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William J Meadus Tyler D Turner Michael ER Dugan Jennifer L Aalhus Pascale Duff David Rolland Bethany Uttaro Lorna L Gibson 《畜牧与生物技术杂志(英文版)》2014,(1):106-113
Pork is traditionally low in docosahexanoic acid(DHA, C22:6n-3) and deficient in omega-3 fats for a balanced human diet. DHA as triglycerides was commercially prepared from the microalgae Schizochytrium and injected into fresh pork loins. Treatments of a mixed brine control(CON), 3.1% sunflower oil in mixed brine(SF) and a 3.1% DHA oil in mixed brine(DHA) were injected into pork loins at 10 mL/100 g and grilled at 205°C. After cooking, the CON and SF pork loins contained 0.03 to 0.05 mg DHA/g of pork and the DHA injected loins contained approximately1.46 mg DHA/g. This also changed the fatty acid profile of omega-6: omega-3 from, 5 to 1 in the CON pork, to a ratio of 1.7 to 1 in DHA pork. The appearance, odor, oxidation rates and sensory taste, as judged by a trained panel,determined the DHA injected meat to be, ‘slightly desirable' and gave lower ‘off flavour' scores, relative to the CON and SF injected pork. Pork can be fortified with DHA oil to 146 mg/100 g serving, which would meet half the recommended daily omega 3 fatty acid requirements for adult humans and would be desirable in taste. 相似文献
49.
ER Weeks Y Tian JS Urbach K Ide HL Swinney M Ghil 《Science (New York, N.Y.)》1997,278(5343):1598-1601
The mid-latitude atmosphere is dominated by westerly, nearly zonal flow. Occasionally, this flow is deflected poleward by blocking anticyclones that persist for 10 days or longer. Experiments in a rotating annulus used radial pumping to generate a zonal jet under the action of the Coriolis force. In the presence of two symmetric ridges at the bottom of the annulus, the resulting flows were nearly zonal at high forcing or blocked at low forcing. Intermittent switching between blocked and zonal patterns occurs because of the jet's interaction with the topography. These results shed further light on previous atmospheric observations and numerical simulations. 相似文献
50.
水资源短缺和土壤环境污染严重是制约农业可持续健康发展的瓶颈,迫使农民开发和采用可持续的农业生产技术。水分运动机理和氮肥残留行为是评价干旱地区农业水肥管理水平的依据,提高水氮利用效率是降低环境污染这一重要科学问题的重要途径。本研究采用裂区试验设计,以灌溉量为主区,设2250(低灌溉量,W1)、3450(传统灌溉量,W2)和4650 m~3 hm–2 (高灌溉量, W3) 3个灌溉量;设0 (空白, N1)、300 (传统施肥量, N2)和600 kg hm–2 (高施氮量, N3) 3个纯氮投入量,在干旱的中国西北内陆棉区开展2年的田间试验,评估灌溉和施氮策略对水氮运移、籽棉产量、水氮生产效率的影响。结果表明,灌溉量及水氮耦合效应是影响籽棉产量及灌溉水生产力的影响因素,其中灌溉量是主效应。2年均值表明,灌溉量为W1时,施肥量由N1增加至N3,生育期0~80 cm平均土壤含水量呈先显著上升后显著下降的趋势, N2和N3处理较N1处理籽棉产量分别提高13.8%和7.6%,水分利用效率分别提高13.6%和6.8%;灌溉量为W2和W3时,施肥量由N1增加至N3,生育期0~80 cm土层平均含水量... 相似文献