998 resultados para 61.194


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Charles Darwin Foundation for the Galapagos Islands. Map.

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Regiões onde existem atividades portuárias estão mais susceptíveis à contaminação por hidrocarbonetos devido ao trânsito de embarcações e as operações de carga/descarga e, consequentemente, estão mais vulneráveis a sofrer impactos ambientais. Este trabalho avaliou a composição, distribuição e origem de hidrocarbonetos em oito regiões portuárias da costa sudeste brasileira: Santos-SP, São Sebastião-SP, Angra dos Reis-RJ, Itaguaí-RJ, Rio de Janeiro-RJ, Arraial do Cabo-RJ, Macaé-RJ e Vitória-ES. Foram coletadas amostras de sedimentos marinhos superficiais (02 cm) em duas campanhas (2009 e 2010). Para a análise dos hidrocarbonetos alifáticos e dos hidrocarbonetos policíclicos aromáticos (HPAs) foram utilizadas cromatografia em fase gasosa com detector de ionização de chama e cromatografia em fase gasosa acoplada à espectrometria de massas, respectivamente. As concentrações médias e os desvios-padrão do Total de nalcanos (μg g-1), Total de Alifáticos (μg g-1), HPAs Totais (ng g-1) e 16 HPAs prioritários (ng g-1) encontrados foram 6,55 4,52, 123,16 86,12, 1470,24 958,41 e 653,93 482,81 na região do porto de Santos-SP; 2,69 1,16, 35,29 15,22, 756,25 350,28 e 142,35 142,35 na região do porto de São Sebastião-SP; 3,11 2,34, 56,99 78,39, 777,62 821,32 e 82,33 84,62 na região do porto de Angra dos Reis-RJ; 5,58 3,28, 26,55 12,19, 1221,15 1070,87 e 92,28 93,14 na região do porto de Itaguaí-RJ; 5,09 2,03, 179,22 108,16, 3547,27 3081,18 e 1879,05 1792,69 na região do porto do Rio de Janeiro; 1,63 2,15, 51,54 39,50, 366,26 222,89 e 194,83 141,65 na região do porto de Arraial do Cabo-RJ; 3,92 2,69, 50,42 81,30, 643,97 637,61 e 182,46 265,87 na região do porto de Macaé-RJ; e 4,78 4,05, 45,31 32,84, 868,78 874,56 e 258,84 142,89 na região do porto de Vitória-ES, respectivamente. O nível de contaminação por hidrocarbonetos nas regiões estudadas variou de baixo a muito alto, mostrando que estes níveis não são diretamente compatíveis com o tamanho e o desenvolvimento urbano em torno de cada porto. Para a avaliação das fontes de contaminação foram usadas razões diagnósticas selecionadas da literatura. A mistura de fontes (pirolítica e petrogênica) foi considerada predominante na maioria das áreas, indicando a influência das atividades dos portos e dos aportes de entradas de contaminação por vias urbanas, industriais e atmosféricas.

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Contents: UNCSD: Rio+20. Shrimp Aquaculture in Central America. Sovereign Rights of Indigenous Fishers. Access to Fisheries Information. Harmonizing Fishworkers’ Rights. The Delhi MPA Workshop.

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There is apparently great scope for improvement of the design and operational aspects of the gear particularly for the effective exploitation of seasonal fisheries like that of seer, tuna, barracuda etc. In order to evolve improved, yet cheap trolling gear regular investigations were undertaken by the Craft & Gear Wing of the Central Institute of Fisheries Technology, off Cochin for five fishing seasons and the results of these studies are incorporated in this paper.

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光敏核不育水稻农垦58S是石明松于1973年在晚粳农垦58的大田中发现的雄性不育突变体,它在长日照下雄性不育可被用于与恢复系杂交生产杂种,而在短日照下雄性可育能用于自交繁殖,它的恢复系来源广泛。基于这些特性,育种学家用光敏核不育水稻建立的二系杂交水稻制种技术有很大的应用潜力。近十几年来,育种学家用农垦58S作基因供体转育了许多新的不育系,研究结果表明育成的粳型不育系均为光敏不育系,但在育成的籼型不育系中,绝大多数丧失光敏核不育特性,变成温敏不育系。目前因不知光敏核不育的分子遗传机制,尚不能解释这些问题。 本文用双向电泳技术分析了农垦58S和农垦58苗期和育性转换光敏感期叶绿体蛋白质的差异,在农垦58S中发现三个蛋白质(Pl,P2和P3),其中Pl和P2在苗期和光敏感期叶片内均存在,P3仅在光敏感期的叶片中存在,它们不受长日照或短日照处理的影响。农垦58没有这三个蛋白质。 用制备型双向电泳纯化后,得到SDS - PAGE和IEF纯的Pl和P2。经SDS-PAGE和IEF测定,Pl的等电点是6.2,分子量是41 kDa;P2的等电点是5.8,分子量是61 kDa。现称Pl为P41,P2为P61。氨基酸序列分析和同源性检索发现P41与水稻叶绿体ATP合成酶p亚基和酵母转录因子CAD1有同源性,此外,P41的N-端序列中有一个与蛋白激酶催化核心中的多功能motif Y-G-X-G-X- (P/T)-G-V相似的序列;P61的14个氨基酸长的N-端序列与水稻叶绿体ATP合成酶β亚基的一致。P41和P61 N-端前12个氨基酸的序列也完全一致。 PCR扩增和Southern杂交分析没有发现农垦58S和农垦58之间ATP合成酶β亚基基因(atpB)的多态性。Nothern杂交分析表明农垦58S中仅有一种、与农垦58 atpB mRNA分子量相同的atpB转录产物,但它的atpB mRNA丰度明显低于农垦58的。没有检测到突变的atpB和其它形式的atpB转录产物。 分析P41和P61在其它水稻材料中的分布特点发现它们在粳型光敏不育系7001S、5088S、31301S、C407S和1647S,籼型光敏不育系W7415S和W9451S以及温(光)敏不育系培矮64S中存在,而在对照材料三系水稻马协A、珍汕97A、马协B、珍汕97B和明恢63以及常规粳稻C94153中不存在。根据这些不育系的系谱和它们与农垦58S之间基因的等位性研究结果,讨论了P41和P61与光敏核不育性的可能联系。

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About 3600 specimens were collected by bottom trawl at 15 sampling stations. 24 biometric characters were measured for each specimens at the laboratory.. Microscopic cross – sections of statolith were used for age determination. Sex determination and fecundity were determined. Population dynamics parameters as well as stock as stock assessment including cohort analysis were estimated using FISAT software. The findings showed that Dorsal Mantle Length (DML) and Body weight (BW) of the Indian squid were 133.9 ± 0.78 mm and 99.61 ± 0.95 g respectively. Strong correlation was found between these 2 variables (R2 = 0.90). The maximum age was 5 years. Relationship between DML and age was highly significantly of p ≤ 0.05. Overall sex ratio (M: F = 0.52) was significantly different from the expected 1:1 ratio (p ≤ 0.05). The ovary weight and nidamental glands weight were 7.72 ± 0.0006 g and 3.07 ± 0.0003g respectively. Absolute and relative fecundity of the Indian squid were found to be 122733 ± 30.87 and 2348 ± 0.4 respectively. GSI were 14.35 in April and 8.63 in July. This squid is therefore a spring spawner. The infinite dorsal mantle length were 258.62 mm for females, 194.72 mm for males and 252.02 for both sexes respectively. For population growth and mortality parameters; K (0.65 per year for both sexes, 0.85 per year for males, 0.65 per year for females); t0 (0.24year for both sexes, 0.22 year in females, 0.26 year in male); φ` (2.30 in both sexes, 2.47 for males, 2.37 for females); Z (1.17 per year for both sexes, 1.10 per year in females, 1.39 per year, in males); M (0.70 per year for both sexes, 0.90 for males, 0.67 for females); F(0.27 per year for both sexes, 0.27 per year in males, 0.195 per year in females). Exploitation coefficient were 0.51 per year for both sexes, 0.57 per year males and 0.51 per year females respectively. The results indicates that since the Indian squid is a short live aquatic organism, therefore, the exploitation coefficient could be raised to 0.7 per year. The analysis showed that total biomass and MSY were 10103.5 ton and 2576.4 ton respectively. These findings are the first study of its sort about the Indian squid in the coastal waters of Oman Sea as well as North-West of Indian Ocean.

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为了解侵蚀环境下植被恢复对土壤活性有机碳及碳库管理指数的影响,以典型侵蚀环境黄土丘陵区纸坊沟流域生态恢复30 a植被长期定位试验点为研究对象,选取坡耕地为参照,分析植被恢复过程中土壤碳库各组分和碳库管理指数的演变特征。结果表明,侵蚀环境下植被恢复后土壤碳库各组分含量都得到显著改善,有机碳、活性有机碳和非活性有机碳含量增幅分别为109%~238%,194%~212%和65%~149%,增加速度非活性有机碳>有机碳>活性有机碳。碳库指数和碳库管理指数较坡耕地明显增加,增幅分别为15%~659%和6.5%~414%,说明土壤经营和管理水平较坡耕地得到了显著改善,土壤系统向着良性方向转变。相关性分析表明有机碳、活性有机碳、非活性有机碳、碳库指数、碳库管理指数与土壤主要肥力因子相关性及其密切,可以作为反映生态恢复过程土壤质量演变的指标。不同植被恢复措施可以显著改善土壤碳库含量,增加土壤碳库管理水平,但改善作用不同,总体来说混交林的效果最好,其次为纯林,最后为荒草地,因此在该地区要通过人工促进生态恢复,应以营造混交林为主,纯林为辅的恢复模式。

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A large number of polymorphic simple sequence repeats (SSRs) or microsatellites are needed to develop a genetic map for shrimp. However, developing an SSR map is very time-consuming, expensive, and most SSRs are not specifically linked to gene loci of immediate interest. We report here on our strategy to develop polymorphic markers using expressed sequence tags (ESTs) by designing primers flanking single or multiple SSRs with three or more repeats. A subtracted cDNA library was prepared using RNA from specific pathogen-free (SPF) Litopenaeus vannamei juveniles (similar to 1 g) collected before (0) and after (48 h) inoculation with the China isolate of white spot syndrome virus (WSSV). A total of 224 clones were sequenced, 194 of which were useful for homology comparisons against annotated genes in NCBI nonredundant (nr) and protein databases, providing 179 sequences encoded by nuclear DNA, 4 mitochondrial DNA, and 11 were similar to portions of WSSV genome. The nuclear sequences clustered in 43 groups, 11 of which were homologous to various ESTs of unknown function, 4 had no homology to any sequence, and 28 showed similarities to known genes of invertebrates and vertebrates, representatives of cellular metabolic processes such as calcium ion balance, cytoskeleton mRNAs, and protein synthesis. A few sequences were homologous to immune system-related (allergens) genes and two were similar to motifs of the sex-lethal gene of Drosophila. A large number of EST sequences were similar to domains of the EF-hand superfamily (Ca2+ binding motif and FRQ protein domain of myosin light chains). Single or multiple SSRs with three or more repeats were found in approximately 61 % of the 179 nuclear sequences. Primer sets were designed from 28 sequences representing 19 known or putative genes and tested for polymorphism (EST-SSR marker) in a small test panel containing 16 individuals. Ten (53%) of the 19 putative or unknown function genes were polymorphic, 4 monomorphic, and 3 either failed to satisfactorily amplify genomic DNA or the allele amplification conditions need to be further optimized. Five polymorphic ESTs were genotyped with the entire reference mapping family, two of them (actin, accession #CX535973 and shrimp allergen arginine kinase, accession #CX535999) did not amplify with all offspring of the IRMF panel suggesting presence of null alleles, and three of them amplified in most of the IRM F offspring and were used for linkage analysis. EF-hand motif of myosin light chain (accession #CX535935) was placed in ShrimpMap's linkage group 7, whereas ribosomal protein S5 (accession #CX535957) and troponin I (accession #CX535976) remained unassigned. Results indicate that (a) a large number of ESTs isolated from this cDNA library are similar to cytoskeleton mRNAs and may reflect a normal pathway of the cellular response after im infection with WSSV, and (b) primers flanking single or multiple SSRs with three or more repeats from shrimp ESTs could be an efficient approach to develop polymorphic markers useful for linkage mapping. Work is underway to map additional SSR-containing ESTs from this and other cDNA libraries as a plausible strategy to increase marker density in ShrimpMap.