946 resultados para Vespasiano, Emperador de Roma, 9-79.


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Nematopalaemon tenuipes is an important component of non-penaeid prawn resources of the northwest coast of India. During 1979-82 period, it contributed 29.9% to the non-penaeid prawn and 5.6% to the total fish landings of Maharashtra. The von Bertalanffy growth parameter L∞, K and t(sub)0 were 77.38 mm, 1.31 and -0.02 year for the males while for the females these parameters were respectively 87.23 mm, 1.30 and -0.01 year. The natural mortality coefficient (M) was 3.54 and 3.52 and the average total mortality coefficient (Z) during the period was 9.09 and 7.79 for the males and females respectively. With the exploitation rates of 0.61 and 0.55 for the males and females during the period, the total stock of the species was 26,270 tonnes and the standing stock was 3,418 tonnes. The maximum sustainable yield (MSY) of the species under the prevailing fishing conditions was 15,744 tonnes which is close to the average yield of 14,726 tonnes from the nets. Hence further increase in effort is not suggested.

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The intensive collecting of Prof. Dr. F. Starmühlner and Prof. Dr. H. H. Costa in Ceylon in 1970 produced among others some Dysticidae. The material turned out to be especially interesting as it comes all together from running waters, in which otherwise collecting is infrequent. From Sri Lanka quite a lot of species of Dytiscidae are already known.

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潮滩湿地处于海陆相互作用地带,是响应全球变化和人类活动较为敏感的生态系统 之一。潮滩湿地是海岸带一个非常重要的生态类型,作为陆地和海洋过渡区的重要组成 部分,承接来自陆地人类活动带来的大量含氮物质。潮滩湿地氮的生物循环特征不但影 响湿地系统自身的调节机制,而且其在环境介质中的特殊动力学过程也与一系列全球环 境问题息息相关。为了更深入的理解潮滩湿地氮的生物循环特征及其关键机制,论文以 黄河口滨岸潮滩翅碱蓬湿地为研究对象,通过野外样品采集、原位实验、微区试验,研 究了湿地土壤氮的时空分布与化学转化特征,探讨了湿地植物生物量与氮累积季节变化 特征以及湿地植物残体分解及分解过程氮动态特征,建立了湿地植物-土壤系统氮循环 分室模式,主要结论如下:(1)潮滩湿地土壤氮含量具有明显的水平变异和空间结构, TN、NO3 --N 和C/N 具有明显空间分布格局,其空间变异性均以向低潮滩延伸且受潮汐 涨落影响较大的方向最大;微地貌特征和潮汐微域物理扰动是导致空间异质性的两个重 要随机因素,水盐条件、土壤类型和潮汐物理扰动是三个重要结构因素;(2)潮滩湿地 土壤氮含量在不同时期的垂直分布均存在较高变异性,主要与有机质分布、潮汐影响、 水分条件以及陆源影响程度有关;潮滩湿地土壤的氮含量具有明显季节变化特征,主要 与水分状况及受潮汐影响的程度有关;(3)潮滩湿地土壤氮的净矿化/硝化速率均呈波动 变化,并受生物固持、反硝化、温度、水分、C/N 和pH 等因素影响;潮滩湿地0~15cm 土壤的净矿化量和净硝化量分别介于0.33~27.81kg·hm-2 和1.19~15.99kg·hm-2,高潮滩湿 地维持无机氮的能力明显强于中潮滩和低潮滩湿地;(4)两种表现型翅碱蓬的生物量 均具有明显季节变化和空间结构分形特征,二者的地上生物量具有自相似性,分别遵从 D=2.012 和2.366 的分形生长过程;(5)沉积强度显著影响翅碱蓬种子的出苗和幼苗存 活,适度沉积可刺激幼苗生长,重度沉积对幼苗生长则具有抑制作用;沉积可促使幼苗 被埋部分发育为根系,反映了其对潮滩较强沉积环境的特殊适应对策;(6)两种表现 型翅碱蓬根、茎和枯落物的TN 含量均呈递减变化,符合指数衰减模型,叶是二者重要 氮储库,分配比高达46.91±16.97%和55.21±9.79%;中潮滩植被的N/P 为9.87±3.47<14, 其生长受N 限制,低潮滩植被的N/P 为15.73±5.00<16,其生长同时受N、P 限制,但 更受P 限制;(7)潮滩湿地植物残体在水盐含量较高或沉积较强条件下的失重率和分解 速率一般较高,反之则较低;温度、水分、盐分和pH 是影响残体相对分解速率的重要 摘 要 II 因素;(8)当分解环境的养分状况不发生较大改变时,残体相对分解速率在很大程度上 取决于基质质量,当养分状况因潮汐养分交换、潮汐物理扰动、沉积物矿化等发生较大 改变时,残体相对分解速率在很大程度上取决于分解环境养分供给状况;(9)潮滩湿地 植物残体在不同水盐梯度和沉积强度下的氮含量、C/N 的变化模式整体较为一致,水盐 条件和沉积强度对残体氮绝对量的变化具有重要影响,C/N 对分解过程中氮养分的调控 作用更为重要;(

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Small pelagic fish species are mainly caught by gill nets operated by fibre reinforced plastic boats fitted with 8-25hp out board engines, traditional crafts fitted with 8-1hp out board engines and non mechanised traditional crafts. Around 28 to 55% of the small pelagic catch in the study area consisted of trenched sardine Amblygaster sirm during 1995-1997 period. Another 26-36% of the catch composed of other Sardinella species such as Sardinella gibbosa, S. albella, S. sindensis and S. longiceps. Engraulids such as Encrasicholina heteroloba, Stolephorus insularis and Stolephorus indicus and Thryssa spp formed around 3-5% of the catch. The major component of this fishery consisted of Clupeids and Engrauhds and over 65 species ranged between smaller Engraulids to incidental rock fish, sail fish, seer fish, sharks, skates and rays. Around 1.4 to 1.9% of the catch consisted of Chirocentrus dorab, Sphyraenaspp, Scomberomorus spp, Lepturcanthus sp and Megalaspis cordyla. Around 1-11% of the catch consisted of incidentally catches of sharks, rays, skates and sail fish. Another 1.6 to 6% of the catch consisted of Selar crumenophthalamus and Rastrelliger kanagurta. The best fishing season appeared to be from June to October in the west coast and August to December in the south coast. The major components of Amblygaster sirm, Sardinella albella and Sardinella gibbosa were caught within the size ranges of 10.0-22.5 cm, 11.0-13.0 cm and 11.0-15.0 cm respectively. However, smaller sized fish of above species of sizes between 6.9 cm to 9.7 cm total length were incidentally caught in the gill nets operated for small Engraulids with a stretched mesh size of 1.6cm. The overall catch rate for the major fish landing centre at Negombo indicated an increase from 38.5 kg/boat trip during 1984-1990 period to 49.5 kg/boat trip during 1995-1997 period. The catch rate for the dominant species Amblygaster sirm has decreased from 28.17 kg/boat trip during 1983-1990 period to 17.47 kg/boat trip during 1995-1997 period at Negombo. The paper also discusses the changing overall catch rates, change in species abundance and possible management consequences that should be considered.

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患儿男,10岁,因"双侧隐睾"就诊.患儿系足月、顺产、5岁时发现头颅大,经医院诊断为脑积水.几岁时做双侧隐睾手术.患儿身高120 cm.头颅发育不规则,颜面不对称,自小严重的智力低下,说话不清.

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Identification of conserved genomic regions within and between different genomes is crucial when studying genome evolution. Here, we described regions of strong synteny conservation between vertebrate deuterostomes (tetrapods and teleosts) and invertebrat

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A study to measure the heavy metal pollution level in the sediment of coastal and offshore area indicates that high concentration of heavy metals were found around Manora channel and eastern coast of Karachi. In comparison with coastal areas, relatively low concentration of heavy metals was recorded in the offshore area. The result shows that sewage and industrial wastes are the main source of heavy metal pollution in the coastal area. The concentration of heavy metals in the sediments is as follows: Chromium 10.4-33.69, nickel 13.3-47.6, lead 10.0-39.04, cadmium 0.08-0.21, zinc 7.4-73.2 and copper 9.44-18.56 mg/kg. In the offshore areas strong correlation was observed between copper and organic carbon, and calcium carbonate and cadmium. In the shore area such correlation has been recorded among nickel, chromium, zinc, and chromium and copper. The Karachi. coast is viewed as moderately polluted when compared to other continental coastal areas.

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Amphibian skin is a rich resource of antimicrobial peptides, like maximins and maximin Hs from frog Bombina maxima. Novel cDNA clones encoding a precursor protein, which comprises a novel maximin peptide (maximin 9) and reported maximin H3, were isolated from two constructed skin cDNA libraries of B. maxima. The predicted primary structure of maximin 9 is GIGRKFLGGVKTTFRCGVKDFASKHLY-NH2. A surprising substitution is at position 16, with a free cysteine in maximin 9 rather than usual conserved glycine in other reported maximins. Maximin 9, the homodimer form and its Cys(16) to Gly(16) mutant were synthesized and their antimicrobial activities were evaluated. Unlike previously reported maximin 3, the tested bacterial and fungal strains were resistant to maximin 9, its homodimer and the Cys(16) to Gly(16) mutant (with MICs > 100 mu M). On the other hand, interestingly, while eight clinical Mollicutes strains were generally resistant to maximin 9 homodimer and its Cys(16) to Gly(16) mutant, most of them are sensitive to maximin 9 at a peptide concentration of 30 mu M, especially in the presence of dithiothreitol. These results indicate that the presence of a reactive Cys residue in maximin 9 is important for its antimycoplasma activity. The diversity of antimicrobial peptide cDNA structures encountered in B. maxima skin cDNA libraries and the antimicrobial specificity differences of the peptides may reflect well the species' adaptation to the unique microbial environments. (c) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

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Effects of different levels of salinity on survival, growth and gonadal development of Genetically Improved Farmed Tilapia (GIFT) were studied under laboratory conditions in glass aquarium, for a period of ten weeks. The initial individual size of the GIFT was 20.23±4.45 and the salinity levels tested were 0, 5, 10, 15 and 20 ppt. The highest survival of 87.5% was found in 0 ppt and the lowest 60.5% in 20 ppt. Though the survival decreased progressively with increased salinity, there were no significant differences (P>0.05) among 0, 5, and 10 ppt. Similar to what has been observed in survival, the specific growth rate (SGR %/day) also decreased as of 1.30, 1.24, 1.08, 0.90 and 0.71, respectively, with the increased salinity of 0, 5, 10, 15 and 20 ppt. The gonadal development was highest in 0 ppt with a GSI value of 3.75 and lowest of 2.01 in 20 ppt. In the second experiment, gonadal development and seed production performance of GIFT in brackishwater condition were investigated for a period of three months. Each of the three fine meshed hapas of 20 square meters made from nylon net was placed in a freshwater (0 ppt) and in a brackish water (10-15 ppt) pond of the Brackishwater Station (BS). GIFT of 65 g average weight from a single cohort were stocked into three hapas at a rate of 2 per m. The male vs female ratio was 1:3. The development of gonad was faster with the higher gonadosomatic index (GSI %) of 3.85 % in freshwater condition than that of 2.73 % in brackish water. Within three months of the study period, a total of 70,510 and 44,250 GIFT fry were produced respectively, in freshwater and brackishwater conditions. Finally under third experiment, a participatory on-farm trial was carried out to evaluate the production performance of GIFT in monoculture and in polyculture with silver barb in coastal freshwater pond conditions. Nine ponds were selected for three treatment combinations of GIFT monoculture (T1), GIFT and silver barb polyculture (T2), and silver barb monoculture (T3). The ponds have been stocked in April, 05 at a density of 25,000 fry per ha. Fishes were fed with rice bran at the rate of 6% bw per day. In one month culture period, GIFT attained an average weight of 16.27 g in monoculture and 17.23 g in polyculture, against an average stocking weight of 0.37 g. Silver barb reached an average weight of 16.62 g in polyculture with GIFT and 10.01 g in monoculture, against an average stocking weight of 3.79 g.