966 resultados para Fishes Larvae Geographical distribution


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Global environmental change (GEC) is an increasingly discussed phenomenon in the scientific literature as evidence of its presence and impacts continues to grow. Yet, while the documentation of GEC is becoming more readily available, local perceptions of GEC— particularly in small-scale societies—and preferences about how to deal with it, are still largely overlooked. Local knowledge and perceptions of GEC are important in that agents make decisions (including on natural resource management) based on individual perceptions. We carried out a systematic literature review that aims to provide an exhaustive state-of-the-art of the degree to and manner in which the study of local perceptions of change are being addressed in GEC research. We reviewed 126 articles found in peer-reviewed journals (between 1998 and 2014) that address local perceptions of GEC. We used three particular lenses of analysis that are known to influence local perceptions, namely (i) cognition, (ii) culture and knowledge, and (iii) possibilities for adaptation.We present our findings on the geographical distribution of the current research, the most common changes reported, perceived drivers and impacts of change, and local explanations and evaluations of change and impacts. Overall, we found the studies to be geographically biased, lacking methodological reporting, mostly theory based with little primary data, and lacking of indepth analysis of the psychological and ontological influences in perception and implications for adaptation. We provide recommendations for future GEC research and propose the development of a “meta-language” around adaptation, perception, and mediation to encourage a greater appreciation and understanding of the diversity around these phenomena across multiple scales, and improved codesign and facilitation of locally relevant adaptation and mitigation strategies.

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Sea urchins are benthic macroinvertebrates that inhabit shallow coastal waters in tropical and temperate zones. Urchins are usually classified as generalists or omnivores as they can adjust their diet according to the food resources available in the environment. Due to the strong grazing pressure they may exert, urchins have an important role in marine ecosystems, occupying different trophic levels and stimulating the intensification of the dynamics of communities where they occur. In 2004, a monitoring program focused on the population dynamics of the white sea urchin, Tripneustes ventricosus, has been initiated in the Fernando de Noronha Archipelago. At the same time, a surprisingly lack of information on the species biology has been noted, despite their wide geographical distribution and economic importance in many parts of its range. Hence, this work was developed to provide information on the feeding habits of T. ventricosus in the archipelago. Ten specimens were collected between December 2006 and July 2007 at two sites of the archipelago, Air France and Sueste Bay for biometrics and analysis of gut contents. Test diameters ranged from 9.19 cm (± 1.1) to 10.08 cm (± 0.58). Calculated stomach repletion index (IRE) was higher (p <0.05) in the Air France site and also during January and July. The IRE was not correlated to the gonad index. Fifteen different species of algae were detected in a total of 120 stomachs examined: 4 Chlorophytas, 4 Phaeophytas and 6 Rhodophytas. Food diversity (p <0.05) was higher in December 2006 and January 2007. Although several items had a high frequency of occurrence, they were low represented in terms of weight, and consequently, had a low level of relative importance. The brown algae Dictyopteris spp and Dictyota spp, followed by the green algae Caulerpa verticillata accounted for the greatest importance in T. ventricosus diet, comprising about 90% of the consumed items

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O vírus Zika (Flavivirus) é um arbovírus transmitido sobretudo por mosquitos, mas também, por transmissão materno-fetal e sexual. Existem evidências que as infeções por vírus Zika podem estar associadas à síndrome de Guillian-Barré e a casos congénitos de microcefalia e outras malformações do sistema nervoso central. As infeções por vírus Zika, Dengue e Chikungunya partilham, atualmente, os mosquitos vetores, a sintomatologia e a distribuição geográfica. O Centro de Estudos de Vetores e Doenças Infeciosas do Instituto Nacional de Saúde Doutor Ricardo Jorge no seu Laboratório Nacional de Referência de Vírus Transmitidos por Vetores tem desenvolvido o diagnóstico e estudos epidemiológicos de vírus transmitidos por artrópodes desde o princípio dos anos 90. O diagnóstico de Zika foi desenvolvido e padronizado em 2007. O laboratório desenvolveu testes de diagnóstico molecular e serológico tendo identificado vários casos de importação para o território português e feito o diagnóstico diferencial com Dengue e Chikungunya e o despiste de infeção em grávidas e em casos de transmissão sexual.

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Fish species and subspecies occurring in fresh water in the North of Vietnam are systematically described. Their geographical distribution is given.

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The eggplant ( Solanum aethiopicum ) is the species of the Solanum genus, whose geographical distribution is broadest. It is grown throughout tropical Africa, and includes three groups of cultivars commonly called African or indigenous eggplant. Kumba group or “bitter eggplant” is an important Solanaceous vegetable crop in Burkina Faso. The objective of this study was to determine genetic variability, strength of association and level of heritability among agronomic interest traits. Phenotypic and genotypic variations and heritability of 14 traits were estimated in 61 accessions at Institut de Développement Rural (IDR), Gampela in Burkina Faso. High phenotypic and genotypic coefficients of variation were observed for fruit diameter, number of seeds per fruit, fruit weight, leaf blade length and width, and height at flowering. In addition, genetic and phenotypic variances were high for the number of seed, fruit weight, plant height at flowering and days to 50% flowering. High heritability estimates were recorded for all traits. Fruit weight showed a positive association with fruit diameter and thickness. The fifty percent flowering cycle registered positive correlations with plant height and fruit diameter. Fruit number showed a negative association with fruit weight and diameter, and 50% flowering cyle.

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Visceral leishmaniasis (VL) has a wide geographical distribution in tropical and subtropical areas of the planet, which is a protozoan parasite of the genus Leishmania. This pathogen is transmitted to the host through the sandflies bite, with its saliva, the immune response that leads to both. In the state of Rio Grande do Norte, 85% of the sand flies captured is Lutzomyia longipalpis, but the second most abundant, Lutzomyia evandroi, it deserves emphasis because its wide distribution and eclectic behavior. The exposure of people living in endemic areas for the insect vector VL greatly increases the chances of infection. This study aimed to evaluate aspects of the epidemiological profile of VL in endemic areas of human and nonendemic in the metropolitan area of Natal, as well as verify the abundance and seasonal fluctuations of sandflies species in two counties endemic for VL. Were collected in the municipalities of Nísia Floresta, Parnamirim, São Gonçalo do Amarante and Macaíba, of which groups of females were separated for further dissection of the salivary glands and identification of species. The blood samples used were from individuals of two Natal s districts where it has never been reported cases of VL and neighborhoods of Parnamirim applicants who present cases of VL. In the municipality of Nísia Floresta, the most abundant species was L. evandroi with 38.39%, followed by L. longipalpis with 36.22%, L. walkeri 19.67% L. lenti 3.81%, L. wellcomei 1.39% and L. whitmani 0.52%. Already in Parnamirim the proportions were L. walkeri with 73.15%, L. evandroi with 10.55%, L. wellcomei 7.63%, L. longipalpis 6.37%, L. whitmani 1.46%, L. sordellii 0.52%, L. intermedia 0.21 and L. shanonni 0.1%. In both municipalities was observed higher abundance of species distributed in the initial months of the year, as February and March. The study showed that no difference in exposure to the vector of VL among individuals from endemic and non endemic area for this disease. But there are differences in exposure between individuals of L. longipalpis and L. evandroi, confirming the great powers of the first vector. It was also characterized as predominant phenotype in the population of endemic areas who had negative serologic responses to antigens of Leishmania and result in negative Montenegro skin test (DTH), indicating that much of the population hasn t been bitten by infected insects

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Background: The present study was undertaken towards the development of SSR markers and assessing genetic relationships among 32 date palm ( Phoenix dactylifera L.) representing common cultivars grown in different geographical regions in Saudi Arabia. Results: Ninety-three novel simple sequence repeat markers were developed and screened for their ability to detect polymorphism in date palm. Around 71% of genomic SSRs were dinucleotide, 25% tri, 3% tetra and 1% penta nucleotide motives. Twenty-two primers generated a total of 91 alleles with a mean of 4.14 alleles per locus and 100% polymorphism percentage. A 0.595 average polymorphic information content and 0.662 primer discrimination power values were recorded. The expected and observed heterozygosities were 0.676 and 0.763 respectively. Pair-wise similarity values ranged from 0.06 to 0.89 and the overall cultivars averaged 0.41. The UPGMA cluster analysis recovered by principal coordinate analysis illustrated that cultivars tend to group according to their class of maturity, region of cultivation, and fruit color. Analysis of molecular variations (AMOVA) revealed that genetic variation among and within cultivars were 27% and 73%, respectively according to geographical distribution of cultivars. Conclusions: The developed microsatellite markers are additional values to date palm characterization tools that can be used by researchers in population genetics, cultivar identification as well as genetic resource exploration and management. The tested cultivars exhibited a significant amount of genetic diversity and could be suitable for successful breeding program. Genomic sequences generated from this study are available at the National Center for Biotechnology Information (NCBI), Sequence Read Archive (Accession numbers. LIBGSS_039019).

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Students of mumming and guising plays – the seasonal verse dramas performed for over 200 years throughout much of England, Scotland, and northern Ireland – have suffered from having too much information to work with. The first part of this poster presentation outlines and illustrates the situation. There are thousands of places where the plays are known to have been performed, and hundreds of texts have been collected. Furthermore, the plays show some tantalising similarities while simultaneously exhibiting the wide range of variation one would expect from orally transmitted dialogue. Until recently, scholars openly admitted to not knowing where to start with such a flood of material, to the extent that some dismissed the texts altogether as unimportant and irrelevant, focussing instead on the "actions". Fortunately, the introduction of computers has managed to break the impasse and is aiding the intellectual process. Part two shows a case study for one of the tools on the Master Mummers website - the Folk Play Scripts Explorer – which is based on a large database of digitised texts and a typology for individual lines. This allows researchers to search for lines, explore textual variants, and map their geographical distribution. This is yielding some interesting surprises. Seemingly trivial variations often turn out to have discrete distribution patterns, while it transpires that certain "ubiquitous" lines have restricted geographical ranges. Thus, the Scripts Explorer is providing novel insights into how the plays evolved and spread.

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Background: The coloured righteye flounder, Poecilopsetta colorata Günther, 1880 was previously known from the eastern Indian Ocean to the South China Sea and Indonesia. Here, a new record from the western Indian Ocean is reported. Results: The new record is based on a specimen collected on the Sakalaves seamounts at 375 m in depth in the Mozambique Channel during a recent oceanographic survey. Four other teleost fish species including an uncommon ophidiid species, Neobythites somaliaensis Nielsen, 1995 were also collected on the same seamounts. Conclusions: The presence of P. colorata in the Mozambique Channel suggests a broad and Indo-West Pacific wide distribution for this relatively rare deep-sea species. The sequence of the cytochrome oxidase subunit-I for the collected specimen is provided as a genetic reference for further DNA barcoding and systematic studies.

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A simple method developed for genomic DNA isolation from fungus was tested on the red alga, Gelidium sesquipedale (Clem.) Born et Thur., which is commercially exploited for its high sulfated polysaccharide (agar) content. This method is faster, cheaper, and less toxic than conventional phenol/chloroform methods. Random amplified polymorphic DNA (RAPD) amplifications were performed successfully without the necessity of purifying the DNA. RAPD markers were used to investigate the genetic similarity among three natural populations of G. sesquipedale from southern Portugal. Bulked-genomic DNA samples of 15 different individuals were made in each population. These can be conceived of as a sample of the population DNA. Of the 62 primers screened, 41 produced bands and 22 revealed polymorphisms. Genetic similarities among populations were high. Populations that are further away from each other have the lowest similarity coefficients, whereas the intermediate Ingrina population, located on the south coast, showed higher genetic similarity with the Odeceixe population located on the southwest coast, than with the Sao Rafael southern population. This suggests a higher genetic flow between Odeceixe and Ingrina or the result may be a founder effect in the sense that the species has propagated from the east coast to the south coast of Portugal. We conclude that the use of this isolation method with RAPD analysis is appropriate to characterize the genetic variability of this commercial species along its geographical distribution. Large sample sizes can be screened at a relatively low cost. Finding genetic markers for commercial populations of C. sesquipedale may be of industrial interest.

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Trichosporon spp. has gained importance as the cases of immunosuppressed patients increase. The genus Trichosporon includes 6 species of clinical relevance that may cause supericial infections, such as white piedra and onychomycosis, or deep and invasive infections with high mortality rates. These microorganisms have a broad geographical distribution and some species are resistant to antifungal drugs in vitro. The present paper is a review on the virulence factors, associated infections, and in vitro susceptibility of the species with the highest incidence as pathogenic agents in humans.

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Bubo bubo is the largest owl in the world, showing a wide geographical distribution throughout the Palaearctic region. It underwent a demographic decline in many European countries during the last century and was considered “vulnerable” (Annex II of the CITES). Nowadays, it is classified as “Least Concern” according to IUCN. Despite its ecological importance and conservation status, few polymorphic molecular markers are available to study its diversity and population genetics. We report on the isolation and development of 10 new microsatellites for the Eagle owl, B. bubo. All loci (10 tetra-nucleotide) are characterized by high polymorphism levels. Number of alleles ranged from 5 to 13 and expected heterozygosity varied from 0.733 to 0.840. These microsatellites would be very useful to assess the genetic diversity, connectivity patterns and parentage of B. bubo. This information will allow to establish new conservation strategies and improve the management of the species.

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A simple method developed for genomic DNA isolation from fungus was tested on the red alga, Gelidium sesquipedale (Clem.) Born et Thur., which is commercially exploited for its high sulfated polysaccharide (agar) content. This method is faster, cheaper, and less toxic than conventional phenol/chloroform methods. Random amplified polymorphic DNA (RAPD) amplifications were performed successfully without the necessity of purifying the DNA. RAPD markers were used to investigate the genetic similarity among three natural populations of G. sesquipedale from southern Portugal. Bulked-genomic DNA samples of 15 different individuals were made in each population. These can be conceived of as a sample of the population DNA. Of the 62 primers screened, 41 produced bands and 22 revealed polymorphisms. Genetic similarities among populations were high. Populations that are further away from each other have the lowest similarity coefficients, whereas the intermediate Ingrina population, located on the south coast, showed higher genetic similarity with the Odeceixe population located on the southwest coast, than with the Sao Rafael southern population. This suggests a higher genetic flow between Odeceixe and Ingrina or the result may be a founder effect in the sense that the species has propagated from the east coast to the south coast of Portugal. We conclude that the use of this isolation method with RAPD analysis is appropriate to characterize the genetic variability of this commercial species along its geographical distribution. Large sample sizes can be screened at a relatively low cost. Finding genetic markers for commercial populations of C. sesquipedale may be of industrial interest.

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Sea urchins are benthic macroinvertebrates that inhabit shallow coastal waters in tropical and temperate zones. Urchins are usually classified as generalists or omnivores as they can adjust their diet according to the food resources available in the environment. Due to the strong grazing pressure they may exert, urchins have an important role in marine ecosystems, occupying different trophic levels and stimulating the intensification of the dynamics of communities where they occur. In 2004, a monitoring program focused on the population dynamics of the white sea urchin, Tripneustes ventricosus, has been initiated in the Fernando de Noronha Archipelago. At the same time, a surprisingly lack of information on the species biology has been noted, despite their wide geographical distribution and economic importance in many parts of its range. Hence, this work was developed to provide information on the feeding habits of T. ventricosus in the archipelago. Ten specimens were collected between December 2006 and July 2007 at two sites of the archipelago, Air France and Sueste Bay for biometrics and analysis of gut contents. Test diameters ranged from 9.19 cm (± 1.1) to 10.08 cm (± 0.58). Calculated stomach repletion index (IRE) was higher (p <0.05) in the Air France site and also during January and July. The IRE was not correlated to the gonad index. Fifteen different species of algae were detected in a total of 120 stomachs examined: 4 Chlorophytas, 4 Phaeophytas and 6 Rhodophytas. Food diversity (p <0.05) was higher in December 2006 and January 2007. Although several items had a high frequency of occurrence, they were low represented in terms of weight, and consequently, had a low level of relative importance. The brown algae Dictyopteris spp and Dictyota spp, followed by the green algae Caulerpa verticillata accounted for the greatest importance in T. ventricosus diet, comprising about 90% of the consumed items

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The marine fish white mullet, Mugil curema Valenciennes, 1836 (Osteichthyes: Mugilidae) exhibits a wide geographical distribution, being common in the Brazilian coast and is an important component of the artisanal fisheries. The objective of this study was to investigate the reproductive biology of M. curema in the coastal waters of Rio Grande do Norte. Fish samples were captured on a monthly basis during August, 2008 to July, 2009. The fish specimens were numbered, weighed, measured, dissected and their gonads were removed, weighed, their sex and gonadal development were identified. The length-weight relationship was determined for males and females. The sex ratio, the size at first gonadal maturation and gonadosomatic index (GSI) were calculated and ovarian development was investigated using macroscopic and histological techniques. The fecundity, spawning type and the reproductive period of the species were determined. A total of 366 specimens (186 males and 180 females) were captured. The sex ratio was 1:1 and the females were heavier than males. The estimated values of the angular coefficient for both sexes suggest that the species has isometric growth. The size at which 50% of the population began the process of maturation was 25.9 cm of total length for grouped sex. The macroscopic characteristics of the ovaries showed four stages of development: immature, maturing, mature and spent. However, the microscopic characteristics of the ovaries showed five stages of development: immature, early maturing, late maturing, mature and spent. The development of oocytes indicated five phases: Chromatin-nucleolus (phase I), initial perinucleolar (phase II), final perinuclear (phase II), formation of vitelline vesicle or yolk (phase III), vitellogenic (phase IV) and complete vitellogenesis (phase V). The species has a prolonged spawning period, with two peaks coinciding with the rainy season.