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91.
F. P. Lima A. B. Nobile D. Freitas Souza C. A. Siqueira C. A. Lemos B. Abreu‐Santos J. A. P. Santos 《Zeitschrift fur angewandte Ichthyologie》2017,33(3):600-603
Length–weight relationships (LWRs) for 35 freshwater fish species from the SP/RJ coastal basin in Brazil are presented in this paper. Fishes were captured between 2011 and 2015 on an irregular basis using electrofishing, sieves, trawl nets, cast nets and fish‐traps. In this study new LWRs are reported for 28 species, plus the total weight and length for 34 and nine species, respectively. The study provides new information on less‐studied species and can serve as a basis for management and conservation in this area. 相似文献
92.
Isolation of Vibrio alginolyticus and Vibrio splendidus from Aquacultured Carpet Shell Clam (Ruditapes decussatus) Larvae Associated with Mass Mortalities 下载免费PDF全文
Two episodes of mortality of cultured carpet shell clams (Ruditapes decussatus) associated with bacterial infections were recorded during 2001 and 2002 in a commercial hatchery located in Spain. Vibrio alginolyticus was isolated as the primary organism from moribund clam larvae that were obtained during the two separate events. Vibrio splendidus biovar II, in addition to V. alginolyticus, was isolated as a result of a mixed Vibrio infection from moribund clam larvae obtained from the second mortality event. The larval mortality rates for these events were 62 and 73%, respectively. Mortality was also detected in spat. To our knowledge, this is the fist time that these bacterial species have been associated with larval and juvenile carpet shell clam mortality. The bacterial strains were identified by morphological and biochemical techniques and also by PCR and sequencing of a conserved region of the 16S rRNA gene. In both cases bacteria isolated in pure culture were inoculated into spat of carpet shell clams by intravalvar injection and by immersion. The mortality was attributed to the inoculated strains, since the bacteria were obtained in pure culture from the soft tissues of experimentally infected clams. V. alginolyticus TA15 and V. splendidus biovar II strain TA2 caused similar histological lesions that affected mainly the mantle, the velum, and the connective tissue of infected organisms. The general enzymatic activity of both live cells and extracellular products (ECPs), as evaluated by the API ZYM system, revealed that whole bacterial cells showed greater enzymatic activity than ECPs and that the activity of most enzymes ceased after heat treatment (100°C for 10 min). Both strain TA15 and strain TA2 produced hydroxamate siderophores, although the activity was greater in strain TA15. ECPs from both bacterial species at high concentrations, as well as viable bacteria, caused significant reductions in hemocyte survival after 4 h of incubation, whereas no significant differences in viability were observed during incubation with heat-killed bacteria. 相似文献
93.
Lemos MC Roberts JT 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1498):1897-1902
This article examines four periods of environmental policy-making in the Amazon region of Brazil. It specifically analyses the role of pro-environment and pro-development policy networks in affecting policy design and implementation. It argues that the efforts of environmentalist networks trying to advocate or block relative developmentalist policies in the Amazon depend on three critical factors-whether they are able to attract the support of elites (or at least block their developmentalist policy initiatives); the type and level of international support they have; and the organizational and financial resources that they are able to mobilize. In analysing the four periods, this article finds that while international influences and resources have been substantial in enabling environmentalist networks to flourish and influence the policy, their effectiveness has been nearly always outweighed by Brazilian developmentalist interests. The outcome in each phase has been a different form of stalemate on environmental protection, and the deforestation continued each time, albeit at slower rates. These findings suggest that the key for significantly lower rates of deforestation on the Amazon may be in the ability of pro-environment networks to neutralize opposition by creating an incentive structure that 'compensates' potential losers of policies that promote conservation. 相似文献
94.
95.
By K. Meirelles Felizola Freire G. Rodrigues Alves Rocha I. Lemos Souza 《Zeitschrift fur angewandte Ichthyologie》2009,25(3):356-357
Length–weight relationships (TW = a TL b ) were estimated for fish species caught by bottom shrimp trawl in southern Bahia (Brazil) from March 2003 to February 2005. The results indicate that all 21 estimated relationships had a ' b ' within the usual range (2.5–3.5). Two new maximum size records were established: 19.2 cm for Odontognathus mucronatus and 16.1 cm for Stellifer brasiliensis . 相似文献
96.
97.
Aluísio M. Fonseca Francisco Jose Q. Monte Maria da Conceio F. de Oliveira Marcos C. de Mattos Geoffrey A. Cordell Raimundo Braz-Filho Telma L.G. Lemos 《Journal of Molecular Catalysis .B, Enzymatic》2009,57(1-4):78-82
A series of aliphatic and aromatic aldehydes and ketones was reduced using plant cell preparations from coconut juice, Cocos nucifera, also called ACC (água-de-coco do Ceará). The reduced products were typically obtained in excellent yields (%) and with very high enantiomeric excess. Esters, amides, and nitrobenzene, yielded acids, amines and an azoxyderivative with satisfactory results. 相似文献
98.
Background
Protein translocation across the membrane of the Endoplasmic Reticulum (ER) is the first step in the biogenesis of secretory and membrane proteins. Proteins enter the ER by the Sec61 translocon, a proteinaceous channel composed of three subunits, α, β and γ. While it is known that Sec61α forms the actual channel, the function of the other two subunits remains to be characterized.Results
In the present study we have investigated the function of Sec61β in Drosophila melanogaster. We describe its role in the plasma membrane traffic of Gurken, the ligand for the Epidermal Growth Factor (EGF) receptor in the oocyte. Germline clones of the mutant allele of Sec61β show normal translocation of Gurken into the ER and transport to the Golgi complex, but further traffic to the plasma membrane is impeded. The defect in plasma membrane traffic due to absence of Sec61β is specific for Gurken and is not due to a general trafficking defect.Conclusion
Based on our study we conclude that Sec61β, which is part of the ER protein translocation channel affects a post-ER step during Gurken trafficking to the plasma membrane. We propose an additional role of Sec61β beyond protein translocation into the ER. 相似文献99.
Gleison Antônio Casagrande Cristiano Raminelli Sebastião de Souza Lemos 《Inorganica chimica acta》2011,365(1):492-495
In this work we have investigated the reaction for the obtention of an uncommon complex salt of the organotellurium bromide class. The reaction was carried out without the isolation of the synthetic intermediates in one-pot procedure. The complex salt obtained presents the tellurium atoms with mixed oxidation states (TeII and TeIV). The cationic unit [5-Br-2-CH3O-C6H3Te(ETU)]+ presents the TeII atom with a “T” shape coordination geometry, and the anionic unit [4-CH3O-C6H4TeBr4]− presents the TeIV atom with an octahedral coordination geometry considering the Te···Br interaction of 3.600(6) Å from the dimeric arrangement presented in the solid state. Intermolecular (Te···Br) secondary bonds, built up the crystalline/molecular structure. Solution NMR data are presented and discussed in the light of the X-ray structure. 相似文献
100.
Maíra F. Goulart Maria B. Lovato Fernanda de Vasconcellos Barros Fernando Valladares José P. Lemos‐Filho 《Biotropica》2011,43(6):695-703
Light intensity and heterogeneity are some of the main environmental factors that differ between forest and savanna habitats, and plant species from these habitats form distinct functional types. In this study, we tested the hypothesis that not only differences in morphological and physiological traits but also phenotypic plasticity in response to light are involved in adaptation to forest and savanna habitats by investigating ecotypic differentiation between populations of Plathymenia reticulata (Leguminosae: Mimosoideae), a tree from the Brazilian Atlantic Forest and the Brazilian Cerrado (savanna). Seeds from four natural populations (one from each biome core area and two from ecotonal regions) were grown in a common garden with four light treatments. Fifteen morphological and physiological characteristics were evaluated until individuals reached 6 mo old. Comparisons among populations showed differences for seven traits in at least one light treatment. These differences pointed to local adaptation to different biomes. Populations showed different levels of phenotypic plasticity in response to light in seven traits. Higher plasticity was found either in the forest core population or ecotonal populations; lower values were found in the cerrado core population. Lower plasticity in the cerrado population emphasizes the stress resistant syndrome, as lower plasticity is probably advantageous in a habitat where a conservative resource use is crucial. Higher plasticity in forest individuals suggests higher ability in exploiting the light heterogeneity in this habitat. Also, higher plasticity in ecotonal populations can be important to ensure the maintenance of P. reticulata in these temporally and spatially dynamic areas. Abstract in Portugese is available at http://www.blackwell‐synergy.com/loi/btp . 相似文献