2,478 research outputs found

    Complete mitochondrial genome of the Florida manatee (Trichechus manatus latirotris, Sirenia)

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    The Florida manatee (Trichechus manatus latirostris) is an endangered subspecies of the West Indian manatee (T. manatus), which inhabits inland and marine waters of southeastern United States. In this study, we assembled the mitochondrial genome (mtDNA) of the Florida manatee from whole genome shotgun reads. As a result, we show that the currently annotated T. manatus mtDNA belongs to a different species, the Amazonian manatee (T. inunguis). The newly assembled Florida manatee mtDNA is 16,881 bp in length, with 13 protein-coding genes, two ribosomal RNAs (rRNAs), 22 transfer RNAs (tRNAs) and one non-coding control region (D-loop). Phylogenetic analysis based on the control region indicates the newly assembled mtDNA is haplotype A01, characteristic of T. m. latirostris, while the current mtDNA associated with the Florida manatee genome assembly has a Ti02 haplotype that is found in Amazonian manatees and hybrids

    Estrutura de tamanho e fertilidade em uma população de Eriocnema fulva Naudin (Melastomataceae) no sudeste do Brasil

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    Eriocnema fulva Naudin is an endangered perennial herbaceous plant, endemic to Minas Gerais state, Brazil. This study was conducted in the Jambreiro Forest (19° 58' -59'S and 43° 52' -55' W, 800-1100 m altitude). In an attempt to describe the population size structure and its association with individual fertility, fifteen 1 x 1 m contiguous plots were set. We tagged, counted, and measured a total of 260 individuals in 1997, 1998 and 1999. Young individuals with leaf lamina lengths 10 cm in length did not reproduce was 2.69%. The highest survival probability of the large-sized individuals confirmed the strong correlation between size and survival. The data indicated that size is important for the fertility of E. fulva, and it may be one of the relevant aspects to be considered for analyses of survival probability. The intraspecific competition, which was indicated by negative correlation between fruit production per size unit and density, can affect fertility, as larger plants had higher fruit production.Eriocnema fulva Ă© endĂȘmica no estado de Minas Gerais e Ă© ameaçada de extinção. Este estudo foi realizado na Mata do Jambreiro (19° 58' -59' S e 43° 52'-55' W, 800-1100 m de altitude) Com o objetivo de descrever a estrutura de tamanho da população e suas relaçÔes com a fertilidade dos indivĂ­duos, foram instaladas 15 parcelas contĂ­guas de 1 x 1m. Marcamos, contamos e medimos um total de 260 indivĂ­duos em 1997, 1998 e 1999. Os indivĂ­duos jovens com o comprimento do limbo 10 cm nĂŁo se reproduzirem foi de 2,69%. A maior probabilidade de sobrevivĂȘncia dos indivĂ­duos de maior tamanho confirmou a forte correlação entre tamanho e sobrevivĂȘncia. Os dados mostraram que o tamanho Ă© importante para a fertilidade de Eriocnema fulva e pode ser relevante para anĂĄlises de probabilidade de sobrevivĂȘncia da espĂ©cie. A competição intra-especĂ­fica, indicada pela correlação negativa entre a produção de frutos por unidade de tamanho e a densidade, pode influir na fertilidade, pois plantas maiores apresentaram maior produção de frutos.685693Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq

    New Genetic Insights About Hybridization and Population Structure of Hawksbill and Loggerhead Turtles From Brazil

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    An extremely high incidence of hybridization among sea turtles is found along the Brazilian coast. This atypical phenomenon and its impact on sea turtle conservation can be elucidated through research focused on the evolutionary history of sea turtles. We assessed high-quality multilocus haplotypes of 143 samples of the 5 species of sea turtles that occur along the Brazilian coast to investigate the hybridization process and the population structure of hawksbill (Eretmochelys imbricata) and loggerhead turtles (Caretta caretta). The multilocus data were initially used to characterize interspecific hybrids. Introgression (F2 hybrids) was only confirmed in hatchlings of F1 hybrid females (hawksbill × loggerhead), indicating that introgression was either previously overestimated and F2 hybrids may not survive to adulthood, or the first-generation hybrid females nesting in Brazil were born as recent as few decades ago. Phylogenetic analyses using nuclear markers recovered the mtDNA-based Indo-Pacific and Atlantic lineages for hawksbill turtles, demonstrating a deep genetic divergence dating from the early Pliocene. In addition, loggerhead turtles that share a common feeding area and belong to distinct Indo-Pacific and Atlantic mtDNA clades present no clear genetic differentiation at the nuclear level. Finally, our results indicate that hawksbill and loggerhead rookeries along the Brazilian coast are likely connected by malemediated gene flow

    Crescimento foliar de Eriocnema fulva Naudin (Melastomataceae) em um fragmento florestal no Brasil sudeste

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    Eriocnema fulva Naudin is an endangered herbaceous, perennial, iteroparous, evergreen species geographically restricted to southeastern-center Minas Gerais State, SE Brazil. The individuals occur as patches on rocky riverbanks shaded by seasonal semideciduous Atlantic forest; they are fixed by roots and have a pending stem. Aiming to investigate leaf development and its importance for individual survival, fifteen contiguous plots (1 x 1 m) were set down in Jambreiro Forest (19° 58?-59? S and 43° 52?-55? W, 800-1100 m altitude), in the municipality of Nova Lima. A total of 260 individuals with the largest leaf blade length > 1 cm was tagged and measured in 1997, 1998, and 1999. Leaf expansion was recorded each month during 26 months until April 2000. Plant size was measured through leaf blade length, petiole length, stem length, and number of leaves. Significant changes were detected only after two years, thus indicating that plant growth is slow. The proportion of surviving leaves after two years was 60%. Total blade expansion took over 14 months, a slow growth rate when compared to leaves of other tropical forest canopy and understory species. Long leaf lifespans are to be found in plants exhibiting slow growth, and we observed that some leaves lived longer than three years. Petiole growth can help to better position the leaf in the search for light, thus contributing to the growth and survival of the plant. The relationships among size measures were significant, reinforcing the great contribution of leaf size for plant size. The age of the largest individual was estimated as 36 years based on the median annual leaf production rate.Eriocnema fulva Ă© uma espĂ©cie herbĂĄcea, perene, iteropĂĄrica, com distribuição geogrĂĄfica restrita ao centro-sudeste do Estado de Minas Gerais, Brasil, e ameaçada de extinção. Os indivĂ­duos ocorrem agrupados em paredĂ”es rochosos, na beira de riachos sombreados pela Mata AtlĂąntica estacional semidecĂ­dua e tĂȘm caule que pendem do barranco. Com o objetivo de investigar o desenvolvimento da folha e sua importĂąncia para a sobrevivĂȘncia dos indivĂ­duos, foram instaladas 15 parcelas contĂ­guas de 1 x 1 m na Mata do Jambreiro (19° 58?-59?S, 43° 52?-55? W, 800-1100 m de altitude), municĂ­pio de Nova Lima. Todos os indivĂ­duos cuja maior folha tivesse comprimento do limbo maior ou igual a 1 cm foram marcados, sendo medidos em 1997, 1998 e 1999. O tempo de expansĂŁo da folha foi registrado mensalmente durante 26 meses atĂ© abril de 2000. Na ĂĄrea amostrada foram marcados 260 indivĂ­duos cujo limbo foliar tinha comprimento > 1cm. O tamanho das plantas, medido atravĂ©s do comprimento do limbo e do pecĂ­olo e do nĂșmero de folhas, apresentou mudanças significativas somente apĂłs dois anos, indicando que o crescimento Ă© lento. A proporção das folhas sobreviventes apĂłs dois anos foi de 60%. O tempo necessĂĄrio para a expansĂŁo da folha foi superior a 14 meses e Ă© lento quando comparado com o de outras espĂ©cies do dossel ou do sub-bosque da floresta tropical. Maior longevidade foliar tende a ser encontrada em plantas de crescimento lento. Observamos que algumas folhas tiveram maior longevidade que 3 anos. O crescimento do pecĂ­olo pode ajudar no melhor posicionamento da folha na busca de luz no sub-bosque, contribuindo para o crescimento e sobrevivĂȘncia da planta. As relaçÔes entre a folha e demais medidas de tamanho foram significativas, indicando sua grande importĂąncia para o tamanho de cada planta. A idade do indivĂ­duo de maior tamanho foi estimada em 36 anos atravĂ©s da taxa mediana de produção anual de folhas.110Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq

    Circuito do ar: significando conceitos a partir de pr?ticas experimentais

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    Este trabalho ? um relato de experi?ncia de pr?ticas experimentais sobre o ar, na perspectiva que metodologias alternativas a denominada tradicional podem auxiliar na constru??o do conhecimento na Educa??o em Ci?ncias. A partir dos experimentos realizados acreditamos que o uso de materiais did?ticos alternativos permitem ao estudante uma maior participa??o na constru??o do seu conhecimento, proporcionando um ambiente de ensino-aprendizagem mais proveitoso e prazeroso, tanto para o professor quanto para os estudantes. Com a an?lise dos resultados, constatamos que as atividades experimentais conjuntamente com a discuss?o conceitual influenciaram diretamente no processo de ensino-aprendizagem dos estudantes. Palavras chave: Experimenta??o, PIBID, Educa??o em Ci?ncias

    Synthesis and Anti-Mycobacterium tuberculosis Activity of Imidazo[2,1-b][1,3]oxazine Derivatives against Multidrug-Resistant Strains

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    The emergence of multidrug-resistant strains of M. tuberculosis has raised concerns due to the greater difficulties in patient treatment and higher mortality rates. Herein, we revisited the 2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine scaffold and identified potent new carbamate derivatives having MIC90 values of 0.18–1.63 ÎŒM against Mtb H37Rv. Compounds 47–49, 51–53, and 55 exhibited remarkable activity against a panel of clinical isolates, displaying MIC90 values below 0.5 ÎŒM. In Mtb-infected macrophages, several compounds demonstrated a 1-log greater reduction in mycobacterial burden than rifampicin and pretomanid. The compounds tested did not exhibit significant cytotoxicity against three cell lines or any toxicity to Galleria mellonella. Furthermore, the imidazo[2,1-b][1,3]oxazine derivatives did not show substantial activity against other bacteria or fungi. Finally, molecular docking studies revealed that the new compounds could interact with the deazaflavin-dependent nitroreductase (Ddn) in a similar manner to pretomanid. Collectively, our findings highlight the chemical universe of imidazo[2,1-b][1,3]oxazines and their promising potential against MDR-TB

    Applying multicriteria analysis for choosing the best marination for pork

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    Objective. This research aimed to choose a best marination solution using the Analytic Hierarchy Process (AHP). Materials and methods. Pork meat samples were collected in a commercial slaughterhouse, and they were randomly distributed in four treatments with three different salt contents blend. Color, pH, retention of the solution, exudate and cooking loss, shear force and sensory attributes were assessed and evaluated. Multicriteria analysis using AHP was applied to the results in order to choose the best overall marination solution. Criteria used for selection were the physical and sensory characteristics of meat, and based on these criteria were classified solutions marination. Results. Results showed that the combination of the salts was the best alternative (Na2CO3+NaCl+Na5P3O10), followed by the solutions of (Na2CO3 + NaCl), and (Na5P3O10 + NaCl). Conclusions. All tested solutions with the salts used alone or in combination led to better physical and sensory attributes than the meat not marinated. Key words: Firmness, sodium chloride, sodium tripolyphosphate, texture (Source:CAB)
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