5 research outputs found
The benthic community of the eastern US continental shelf: A literature synopsis of benthic faunal resources
The existing scientific literature on offshore benthic assemblages (OBA) residing along the US East and Gulf of Mexico continental shelf was reviewed. Identification was made of any associations between the dominant OBA and particular sediment types and/or bathymetry. Of special interest was the evaluation of reported effects of sand dredge/mining activities on the dominant OBA and recognition of data deficiencies. One hundred and twenty-two references were selected and classified as to type of study with pertinent results extracted. Polychaetes were predominantly cited as the principal infaunal taxa present in studies from both the Gulf of Mexico and US Atlantic coast. Specifically, Prionospio cristata, Nephtys incisa, N. picta, and Spiophanes bombyx were consistently identified as a common part of the benthic community structure. Surveys from the East Coast indicated a greater diversity of dominant taxa not reported for the Gulf of Mexico than vice-versa. Robust animal–sediment or animal–depth relationships were not readily available. From the few studies available, it appears that general ‘‘recovery’’ from anthropogenic disturbance by benthic assemblages on the continental shelf occurs within three months to 2.5 years. Presently, it is difficult to draw conclusions about approximate benthic faunal recovery times following anthropogenic activities such as sand mining and/or disposal operations because of the paucity of studies
The benthic community of the eastern US continental shelf: A literature synopsis of benthic faunal resources
The existing scientific literature on offshore benthic assemblages (OBA) residing along the US East and Gulf of Mexico continental shelf was reviewed. Identification was made of any associations between the dominant OBA and particular sediment types and/or bathymetry. Of special interest was the evaluation of reported effects of sand dredge/mining activities on the dominant OBA and recognition of data deficiencies. One hundred and twenty-two references were selected and classified as to type of study with pertinent results extracted. Polychaetes were predominantly cited as the principal infaunal taxa present in studies from both the Gulf of Mexico and US Atlantic coast. Specifically, Prionospio cristata, Nephtys incisa, N. picta, and Spiophanes bombyx were consistently identified as a common part of the benthic community structure. Surveys from the East Coast indicated a greater diversity of dominant taxa not reported for the Gulf of Mexico than vice-versa. Robust animal–sediment or animal–depth relationships were not readily available. From the few studies available, it appears that general ‘‘recovery’’ from anthropogenic disturbance by benthic assemblages on the continental shelf occurs within three months to 2.5 years. Presently, it is difficult to draw conclusions about approximate benthic faunal recovery times following anthropogenic activities such as sand mining and/or disposal operations because of the paucity of studies
Estudo das latências e amplitudes dos potenciais evocados auditivos de média latência em indivÃduos audiologicamente normais Middle latency response study of auditory evoked potentials’ amplitudes and lantencies audiologically normal individuals
Estudo de coorte contemporânea com corte transversal. O Potencial Evocado Auditivo de Média Latência (PEAML) é gerado entre 10 e 80ms e possui múltiplos geradores, com maior contribuição da região tálamo-cortical. O estabelecimento de critérios de normalidade para os valores de latência e amplitude é necessário para uso clÃnico. OBJETIVOS: Analisar a latência e amplitude do PEAML em indivÃduos sem alterações audiológicas, e verificar a confiabilidade da amplitude Pa-Nb. MATERIAL E MÉTODO: Foram coletados os PEAML de 25 indivÃduos durante o ano de 2005 e analisados os componentes Na, Pa, Nb para cada orelha testada (A1 e A2), e posicionamento de eletrodo (C3 e C4). RESULTADOS: Observou-se diferença estatisticamente significante entre os valores médios de latência para C3A1 e C4A1 com relação aos componentes Na e Pa, não sendo encontrada esta diferença para o componente Nb e valores médios das amplitudes Na-Pa e Pa-Nb. CONCLUSÃO: Foram estabelecidos os valores das médias e desvios padrão para os parâmetros latência e amplitude dos componentes Na, Pa, Nb, e Na-Pa e Pa-Nb, nas condições C3A1, C4A1, C3A2, C4A2, proporcionando os parâmetros para a análise e interpretação deste potencial.<br>Contemporary cohort cross-sectional study. Introduction: The auditory middle latency response (AMLR) is generated between 10 and 80 ms and has multiple generators, with a greater contribution from the thalamus-cortical pathways. The establishment of normality criteria for latency and amplitude values is necessary for clinical use. AIM: to analyze the latency and amplitude of the AMLR in individuals without audiological disorders, and verify the reliability of Pa-Nb amplitude. MATERIALS AND METHODS: The AMLR of 25 individuals was collected during 2005 and the Na, Pa, Nb components were analyzed for each tested ear (A1 and A2), and electrode positioning (C3 and C4). RESULTS: A statistically significant difference was noticed among middle latency values for C3A1 and C4A1 regarding components Na and Pa, and no difference for component Nb and mean values for amplitudes Na-Pa and Pa-Nb. Conclusions: We established average and standard deviation values for latency and amplitude parameters for components Na, Pa, Nb and Na-Pa and Pa-Nb, under conditions C3A1, C4A1, C3A2, C4A2, providing a parameter for the analysis and interpretation of this potential