Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Proc Biol Sci ; 291(2018): 20232746, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38444338

RESUMEN

Assessing genetic diversity within species is key for conservation strategies in the context of human-induced biotic changes. This is important in marine systems, where many species remain undescribed while being overfished, and conflicts between resource-users and conservation agencies are common. Combining niche modelling with population genomics can contribute to resolving those conflicts by identifying management units and understanding how past climatic cycles resulted in current patterns of genetic diversity. We addressed these issues on an undescribed but already overexploited species of sardine of the genus Harengula. We find that the species distribution is determined by salinity and depth, with a continuous distribution along the Brazilian mainland and two disconnected oceanic archipelagos. Genomic data indicate that such biogeographic barriers are associated with two divergent intraspecific lineages. Changes in habitat availability during the last glacial cycle led to different demographic histories among stocks. One coastal population experienced a 3.6-fold expansion, whereas an island-associated population contracted 3-fold, relative to the size of the ancestral population. Our results indicate that the island population should be managed separately from the coastal population, and that a Marine Protected Area covering part of the island population distribution can support the viability of this lineage.


Asunto(s)
Genómica , Metagenómica , Humanos , Brasil , Salinidad
2.
Sci Total Environ ; 896: 164981, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37364846

RESUMEN

Since the 2019 oil spill on the northeastern coast of Brazil, oil materials have washed up on the beaches. A characteristic of the recent oil spill that began in late August was that some of the oiled material, such as tarballs, contained the goose barnacle species Lepas anatifera (Cirripedia, Lepadomorpha), which is well-known for its cosmopolitan distribution and wide occurrence in the oceans. The findings of this study provide information on the occurrence and contamination of petroleum hydrocarbons in animals adhered to the surfaces of tarballs sampled from beaches in the Brazilian states of Ceará and Rio Grande do Norte, between September and November 2022. The size of the barnacles varied from 0.122 to 2.20 cm, suggesting that the tarballs had been floating in the ocean for at least a month. All groups of L. anatifera collected from the tarballs had polycyclic aromatic hydrocarbons (PAHs) present (∑21PAHs from 476.33 to 3816.53 ng g-1). In comparison to high-molecular-weight PAHs, which are primarily from pyrolytic sources, low-molecular-weight PAHs, such as naphthalene and phenanthrene, which are mostly related to petrogenic sources, were shown to be more abundant. In addition, dibenzothiophene, which is exclusive of petrogenic origin, was found in all samples (30.74-537.76 ng g-1). The aliphatic hydrocarbons (AHs): n-alkanes, pristane, and phytane were also found and displayed petroleum characteristics. These results highlight the danger of increasing the absorption of petrogenic PAHs and AHs by organisms that use tarballs as substrates. L. anatifera is a crucial component of the food chain because many animals such as crabs, starfish, and gastropods consume it.


Asunto(s)
Contaminación por Petróleo , Petróleo , Hidrocarburos Policíclicos Aromáticos , Thoracica , Contaminantes Químicos del Agua , Animales , Petróleo/análisis , Brasil , Monitoreo del Ambiente/métodos , Hidrocarburos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminación por Petróleo/efectos adversos , Contaminación por Petróleo/análisis , Ingestión de Alimentos , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/química
3.
Rev Bras Epidemiol ; 26: e230018, 2023.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-36820755

RESUMEN

OBJECTIVE: To identify the spatial patterns of chikungunya fever (CHIKF) and the associated socioeconomic, demographic, and vector infestation factors in the 1st Health Region of Pernambuco (1st HRP). METHODS: This ecological study used a spatial analysis of Mean Incidence Rates (MIR) of probable cases of CHIKF reported among residents of the 19 municipalities of the 1st HRP, in 2015-2021. The univariate and bivariate global Moran indexes (I) were estimated. From the significant associations (p<0.05), clusters were identified using the local Moran index and maps. RESULTS: A predominance of the largest CHIKF rates was identified in the east. However, there was a heterogeneous distribution of rates across municipalities, which may have contributed to the absence of spatial autocorrelation of CHIKF (I=0.03; p=0.294) in univariate I. The bivariate I revealed a positive spatial correlation between CHIKF and the Municipal Human Development Index (MHDI) (I=0.245; p=0.038), but with a cluster of cities with low incidences and low MHDI in the west. There was no spatial correlation between CHIKF and the other variables analyzed: population density, Gini index, social vulnerability index, and building infestation index for Aedes aegypti. CONCLUSIONS: The results suggest that only the MHDI influenced the occurrence of CHIKF in the 1st HRP, so that municipalities in the west demonstrated spatial dependence between lower values of MHDI and MIR. However, this spatial correlation may have occurred due to possible underreporting in the area. These findings can assist in the (re)orientation of resources for surveillance and health care services.


Asunto(s)
Fiebre Chikungunya , Humanos , Ciudades/epidemiología , Fiebre Chikungunya/epidemiología , Incidencia , Brasil/epidemiología , Análisis Espacial , Factores Socioeconómicos
4.
J Fish Biol ; 102(1): 172-177, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36226898

RESUMEN

The recently described Lutz's stingray Hypanus berthalutzae is endemic to the Brazilian Province, including oceanic islands. Although it is expected to have life-history traits similar to the southern stingray H. americanus, little is known about its reproductive biology. Here we present the first observations of courtship behaviour (n = 4), copulation (n = 3) and an induced parturition of H. berthalutzae at the Fernando de Noronha Archipelago, an insular Marine Protected Area from the Equatorial Atlantic Ocean. The mating event records included (1) 'chasing/close following', (2) 'biting/precopulatory biting', (3) 'insertion/copulation' and (4) 'separation'. These results are especially relevant considering that records of reproductive behaviour in the wild are rare for elasmobranchs in general. Mating events occurred in different months, suggesting that the reproductive cycle of H. berthalutzae in this insular system is asynchronous, as observed for other stingray species in regions with favourable environmental conditions and abundant food throughout the year. The opportunistic documentation of the induced parturition allowed for direct nonlethal observation of the two pups at or near full term in late May. Although preliminary, these observations should be considered in future management plans as they provide relevant data about the life-history traits and mating behaviour of this endemic and threatened species.


Asunto(s)
Elasmobranquios , Rajidae , Animales , Embarazo , Femenino , Brasil , Parto
5.
Rev. bras. epidemiol ; 26: e230018, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1423216

RESUMEN

ABSTRACT Objective: To identify the spatial patterns of chikungunya fever (CHIKF) and the associated socioeconomic, demographic, and vector infestation factors in the 1st Health Region of Pernambuco (1st HRP). Methods: This ecological study used a spatial analysis of Mean Incidence Rates (MIR) of probable cases of CHIKF reported among residents of the 19 municipalities of the 1st HRP, in 2015-2021. The univariate and bivariate global Moran indexes (I) were estimated. From the significant associations (p<0.05), clusters were identified using the local Moran index and maps. Results: A predominance of the largest CHIKF rates was identified in the east. However, there was a heterogeneous distribution of rates across municipalities, which may have contributed to the absence of spatial autocorrelation of CHIKF (I=0.03; p=0.294) in univariate I. The bivariate I revealed a positive spatial correlation between CHIKF and the Municipal Human Development Index (MHDI) (I=0.245; p=0.038), but with a cluster of cities with low incidences and low MHDI in the west. There was no spatial correlation between CHIKF and the other variables analyzed: population density, Gini index, social vulnerability index, and building infestation index for Aedes aegypti. Conclusions: The results suggest that only the MHDI influenced the occurrence of CHIKF in the 1st HRP, so that municipalities in the west demonstrated spatial dependence between lower values of MHDI and MIR. However, this spatial correlation may have occurred due to possible underreporting in the area. These findings can assist in the (re)orientation of resources for surveillance and health care services.


RESUMO Objetivo: Identificar, na Iᵃ Região de Saúde de Pernambuco (Iᵃ RSP), os padrões espaciais da febre de Chikungunya (CHIKF) e os fatores socioeconômicos, demográficos e de infestação vetorial associados. Métodos: Este estudo ecológico utilizou a análise espacial das Taxas Médias de Incidência (TMI) de casos prováveis da CHIKF notificados entre os residentes dos 19 municípios da Iᵃ RSP no período de 2015-2021. Os índices de Moran global (I) univariados e bivariados foram estimados. Das associações significativas (p<0,05), clusters foram localizados por meio do Índice de Moran Local e de mapas. Resultados: Identificou-se predominância das maiores TMI da CHIKF no leste. Entretanto, houve distribuição heterogênea das taxas dos municípios, o que pode ter contribuído para a ausência de autocorrelação espacial da CHIKF (I=0,03; p=0,294) no I univariado. O I bivariado revelou correlação espacial positiva entre a CHIKF e o Índice de Desenvolvimento Humano Municipal (IDHM) (I=0,245; p=0,038), porém com um cluster de cidades com baixas incidências e baixo IDHM no oeste. Não houve correlação espacial entre a CHIKF e as demais variáveis analisadas: densidade demográfica, Índice de Gini, Índice de Vulnerabilidade Social e Índice de Infestação Predial de Aedes aegypti. Conclusões: Os resultados sugerem que somente o IDHM influenciou na ocorrência da CHIKF na Iᵃ RSP, de forma que municípios do oeste demonstraram dependência espacial entre menores valores de IDHM e TMI. No entanto, essa correlação espacial pode ter ocorrido devido às possíveis subnotificações na área. Tais achados podem auxiliar na (re)orientação de recursos dos serviços de vigilância e assistência à saúde.

6.
An Acad Bras Cienc ; 94(suppl 2): e20210536, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36383810

RESUMEN

In 2019 an oil spill spread over more than 4000 km of the Brazilian coastline. Monitoring programs that allow for the evaluation of potential impacts on communities and ecosystems and their recovery through time are needed and rely on baseline information previous to the oil spill. Here we compiled qualitative and quantitative data available from 8 studies on fish and benthic species from different habitats of Rio Grande do Norte (RN) from 2007 to 2018. We assessed the number of species from different locations and compiled information on conservation status and human use. We mapped the study areas and habitats and overlapped them with those affected by the oil spill. The RN state has a high diversity of fish (175 species) and benthic species (285 species), of which more than half of fish (52%) and 2% of benthic species are threatened and 72,8% of fish and 7,9% of benthic species are of commercial interest. Information of most habitats is still poorly known (i.e.majority ofthe available data are from unique and punctual sampling), which may weaken future evaluations of the real impact of the oil spill. Nonetheless, it is possible to design reliable monitoring based on our dataset, persistent contamination and future loss of diversity.


Asunto(s)
Contaminación por Petróleo , Animales , Humanos , Contaminación por Petróleo/efectos adversos , Ecosistema , Brasil , Peces , Biota
7.
An Acad Bras Cienc ; 93(2): e20190715, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34076036

RESUMEN

Spiny lobsters (Family Palinuridae) are a popular seafood in Brazil. We characterize the fishing activity and analyze the population of lobster species captured in the coast of the state of Rio Grande do Norte, Northeast Brazil. We monitored the landings of lobster fishermen at the start of the fishing season, from May 24 to November 21, in 2010, at Pirangi beach, the main landing point in the metropolitan area of Natal. The lobster fisherman in the region use small vessels and a compressor to dive in artificial reefs known as marambaias. The artisanal fishermen are engaged in several illegal practices and revealed a greater capture of lobsters categorized as small-sized for the market (11-13.95cm tail length). The capture area led to different fishing pressures for each species. For P. laevicauda, fishing pressure occurred for all size classes, while for P. meripurpuratus, pressure occurred partially, only for a few population cohorts. On regional scale, fishing involved a demand-supply trade balance centered on the size of capture vs. abundance, regardless of the natural interespecific differences on body size and the preferential distribution area. Our results provide key information for future decision making involving the fishing of spiny lobster.


Asunto(s)
Decápodos , Palinuridae , Animales , Brasil , Explotaciones Pesqueras , Alimentos Marinos
8.
Zootaxa ; 4819(3): zootaxa.4819.3.4, 2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-33056093

RESUMEN

The labrisomid genus Malacoctenus from Southwestern Atlantic is reviewed. Two new species of scaly blennies formerly reported by several authors as Malacoctenus triangulatus are described. One is found at the oceanic islands Fernando de Noronha Archipelago and Atol das Rocas, and the other is distributed along the Brazilian coastline. The two new species differ from other species of the genus and from each other by different combinations of the number of lateral-line scales, number and size of head cirri, and color pattern. Molecular data also support species' distinctiveness between M. triangulatus and the species described herein. Two additional recognized Brazilian species, M. delalandii and M. brunoi are described and illustrated and an identification key to all recognized Atlantic species is provided.


Asunto(s)
Peces , Animales
9.
Int J Nanomedicine ; 14: 865-874, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30774339

RESUMEN

BACKGROUND: It has been difficult to find bioactive compounds that can optimize bone repair therapy and adequate osseointegration for people with osteoporosis. The nano-hydroxyapatite (nHAp)/carbon nanotubes with graphene oxides, termed graphene nanoribbons (GNR) composites have emerged as promising materials/scaffolds for bone regeneration due to their bioactivity and osseointegration properties. Herein, we evaluated the action of nHAp/GNR composites (nHAp/GNR) to promote bone regeneration using an osteoporotic model. MATERIALS AND METHODS: First, three different nHAp/GNR (1, 2, and 3 wt% of GNR) were produced and characterized. For in vivo analyses, 36 Wistar rats (var. albinus, weighing 250-300 g, Comissão de Ética no Uso de Animais [CEUA] n.002/17) were used. Prior to implantation, osteoporosis was induced by oophorectomy in female rats. After 45 days, a tibial fracture was inflicted using a 3.0-mm Quest trephine drill. Then, the animals were separated into six sample groups at two different time periods of 21 and 45 days. The lesions were filled with 3 mg of one of the above samples using a curette. After 21 or 45 days of implantation, the animals were euthanized for analysis. Histological, biochemical, and radiographic analyses (DIGORA method) were performed. The data were evaluated through ANOVA, Tukey test, and Kolmogorov-Smirnov test with statistical significance at P<0.05. RESULTS: Both nHAp and GNR exhibited osteoconductive activity. However, the nHAp/GNR exhibited regenerative activity proportional to their concentration, following the order of 3% >2% >1% wt. CONCLUSION: Therefore, it can be inferred that all analyzed nanoparticles promoted bone regeneration in osteoporotic rats independent of analyzed time.


Asunto(s)
Regeneración Ósea , Durapatita/química , Grafito/química , Nanotubos de Carbono/química , Osteoporosis/patología , Fosfatasa Alcalina/metabolismo , Animales , Regeneración Ósea/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Nanotubos de Carbono/ultraestructura , Osteoporosis/fisiopatología , Ovariectomía , Ratas Wistar , Tibia/diagnóstico por imagen , Andamios del Tejido/química
10.
Zookeys ; (746): 91-104, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29674897

RESUMEN

Poecilia vivipara, a small euryhaline guppy is reported at the Maceió River micro-basin in the Fernando de Noronha oceanic archipelago, northeast Brazil. However, the origin (human-mediated or natural dispersal) of this insular population is still controversial. The present study investigates how this population is phylogenetically related to the surrounding continental populations using the cytochrome oxidase I mitochondrial gene from eleven river basins in South America. Our phylogenetic reconstruction showed a clear geographical distribution arrangement of P. vivipara lineages. The Fernando de Noronha haplotype fell within the 'north' clade, closely related to a shared haplotype between the Paraíba do Norte and Potengi basins; the geographically closest continental drainages. Our phylogenetic reconstruction also showed highly divergent lineages, suggesting that P. vivipara may represent a species complex along its wide distribution. Regarding to the insular population, P. vivipara may have been intentionally introduced to the archipelago for the purpose of mosquito larvae control during the occupation of a U.S. military base following World War II. However, given the euryhaline capacity of P. vivipara, a potential scenario of natural (passive or active) dispersal cannot be ruled out.

11.
Mar Environ Res ; 129: 365-373, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28687428

RESUMEN

One of the more challenging tasks in Marine Spatial Planning (MSP) is identifying critical areas for management and conservation of fish stocks. However, this objective is difficult to achieve in data-poor situations with different sources of uncertainty. In the present study we propose a combination of hierarchical Bayesian spatial models and remotely sensed estimates of environmental variables to be used as flexible and reliable statistical tools to identify and map fish species richness and abundance hot-spots. Results show higher species aggregates in areas with higher sea floor rugosity and habitat complexity, and identify clear richness hot-spots. Our findings identify sensitive habitats through essential and easy-to-use interpretation tools, such as predictive maps, which can contribute to improving management and operability of the studied data-poor situations.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Explotaciones Pesqueras/estadística & datos numéricos , Peces/clasificación , Animales , Peces/crecimiento & desarrollo
12.
Mar Environ Res ; 125: 1-9, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28038347

RESUMEN

Ecological barriers are important determinants of the evolution and distributions marine organisms, and a challenge for evolutionary ecologists seeking to understand population structure in the sea. Dasyatis marianae is an endemic Brazilian species that indicates certain restrictions on its distribution probably due to marine barriers. In this study, Bayesian hierarchical spatial models, jointly with environmental and occurrence species data, are used to identify, which elements could generate these barriers on Dasyatis marianae distribution. Results show that salinity and temperature are the most important drivers that play an essential role to limit the distribution of this species. Indeed, low salinity values restrict Dasyatis marianae distribution in the north of the Brazilian coast, while in the south are colder temperatures. These results highlight the need to better define the distribution of marine species, especially for the ones affected by ecological barriers that are more sensitive to environmental changes.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Rajidae/fisiología , Animales , Organismos Acuáticos , Teorema de Bayes , Brasil , Ecología , Ambiente
13.
PLoS One ; 11(6): e0157472, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27309356

RESUMEN

The Tropical Southwestern Atlantic is characterized by prominent ecosystems with large-scale oceanographic complexity. Yet, the evolutionary processes underlying genetic differentiation and connectivity in this region remain largely unknown. Entomacrodus vomerinus (Valenciennes, 1836) is a demersal fish with planktonic larvae endemic to this marine province, inhabiting shallow tidal pools in continental and oceanic reef environments. We evaluated the population structure, genetic diversity and gene flow of E. vomerinus using mitochondrial data (CYTB and COI) and nuclear (rhodopsin, RHO) DNA sequences. We sampled a total of 85 individuals, comprising 46 from three oceanic archipelagos with varying distance from the coast (São Pedro and São Paulo-SS, Fernando de Noronha-FE and Rocas Atoll-RA) and 39 from two localities in northeastern Brazilian coast (Rio Grande do Norte-RN and Bahia-BA). Multilocus analysis revealed the presence of three Evolutionarily Significant Units-ESUs (SS, FE+RA, and RN+BA), which are in accordance with distinct marine ecoregions. Coalescent analyses showed that the central ESU has a larger effective population size than the other two, suggesting strong asymmetries in the genetic diversity across the species range. Moreover, they showed that gene flow is highly asymmetric, suggesting a source-sink dynamics from the central ESU into the remaining ones, in agreement with oceanic currents. Together, these results provide insights in the evolutionary mechanisms facilitating diversification in this marine province.


Asunto(s)
ADN Mitocondrial/genética , Proteínas de Peces/genética , Genética de Población , Perciformes/genética , Distribución Animal , Animales , Océano Atlántico , Brasil , Ecosistema , Flujo Génico , Variación Genética , Tipificación de Secuencias Multilocus , Perciformes/clasificación , Filogenia , Densidad de Población , Rodopsina/genética , Análisis de Secuencia de ADN , Clima Tropical
14.
Psicol. USP ; 22(1): 81-98, 2011. ilus
Artículo en Portugués | Index Psicología - Revistas | ID: psi-47190

RESUMEN

O objetivo foi medir a Função de Sensibilidade ao Contraste (FSC) de pacientes com migrânea e de voluntários saudáveis sem a patologia. Participaram dos testes 12 voluntários do sexo feminino, seis com migrânea e seis sem migrânea na faixa etária de 20 a 37 anos. As medidas de FSC foram realizadas utilizando estímulos visuais estáticos de grades senoidais angulares com frequências espaciais de 2, 3, 4, 24 e 64 ciclos/360º Foi utilizado o método psicofísico da escolha forçada entre duas alternativas temporais, condições de luminância fotópica (luminância média da tela de 41 cd/m²) e visão binocular com pupila natural. Os resultados demonstram que a percepção visual de contraste dos voluntários com migrânea foi menor nas frequências de 2, 3, 4 e 64 ciclos/360º. Esses achados preliminares sugerem alterações na FSC relacionadas a essa patologia(AU)


In this work, the aim was to measure the Contrast Sensitivity Function (CSF) among patients with, and healthy volunteers without this pathology. The subjects of the tests were 12 female volunteers, aged 20-37 years, six of them with migraine, and six other ones without migraine. CSF measurements were performed using static visual stimuli of angular sine-wave gratings, with spatial frequencies of 2, 3, 4, 24 and 64 cycles/360º. Method used was the psychophysical one, with forced choice between two temporal alternatives, conditions of photopic luminance (screen average luminance of 41 cd/m²), and binocular vision with natural pupil. The results demonstrate that visual perception of contrast by the volunteers with migraine was lower in the frequencies of 2, 3, 4 and 64 cycles/360°. These preliminary findings suggest changes in the CSF related to this pathology(AU)


Dans ce travail, l'objectif était celui de mesurer la Fonction de Sensibilité au Contraste (FSC) chez des patients souffrant de migraine et des volontaires sains sans cette pathologie. Ont participé des tests 12 volontaires du sexe féminin, âgées de 20-37 ans, six avec de la migraine et six sans migraine. Les mesures de FSC ont été réalisées avec des stimuli visuels statiques des grilles d'ondes sinusoïdales angulaires, avec des fréquences spatiales de 2, 3, 4, 24 et 64 cycles/360º. La méthode utilisée a été la psychophysique, avec choix forcé entre deux alternatives temporelles, les conditions de luminosité photopique (luminance moyenne par écran de 41 cd/m²) et la vision binoculaire avec des pupilles naturelles. Les résultats démontrent que la perception visuelle de contraste par les volontaires souffrant de migraine a été plus faible dans les fréquences de 2, 3, 4 et 64 cycles/360°. Ces résultats préliminaires suggèrent des changements dans le FSC liés à cette pathologie(AU)


En este trabajo, el objetivo era medir la función de sensibilidad al contraste (CSF) en pacientes con y voluntarios sanos sin esta patología. Los sujetos de los ensayos fueron 12 mujeres voluntarias, con edades entre 20-37 años - seis de ellos con la migraña, y seis otros sin migraña. Mediciones LCR se realizaron mediante estímulos visuales estáticos de rejilla angular de onda sinusoidal, con frecuencias espaciales de 2, 3, 4, 24 y 64º cycles/360. El método utilizado fue el psicofísico con elección forzada entre dos alternativas temporales, las condiciones de luminosidad fotópica (luminancia de pantalla media de 41 cd / m²) y la visión binocular con pupila natural. Los resultados demuestran que la percepción visual de contraste por los voluntarios con migraña fue menor en las frecuencias de 2, 3, 4 y 64 cycles/360°. Estos hallazgos preliminares sugieren cambios en el LCR en relación aesta patología(AU)


Asunto(s)
Humanos , Femenino , Adulto Joven , Adulto , Migraña sin Aura/psicología , Sensibilidad de Contraste , Percepción Visual
15.
Psicol. USP ; 22(1): 99-116, 2011. ilus
Artículo en Portugués | Index Psicología - Revistas | ID: psi-47191

RESUMEN

O objetivo deste trabalho foi comparar a percepção visual de contraste de adultos sem a ingestão de álcool e após a ingestão moderada de álcool – 0,09% Blood Alcohol Concentration (BAC), através da Função de Sensibilidade ao Contraste (FSC). Participaram dos experimentos cinco voluntárias, na faixa etária de 21 a 30 anos, com acuidade visual normal ou corrigida. Para medir a FSC, foram usados estímulos de grade senoidal radial de frequências de 0,25; 2 e 8 ciclos por grau de ângulo visual. Utilizou-se um delineamento experimental com medidas repetidas e o método psicofísico da escolha forçada. Os resultados demonstraram efeito significante de participantes (F4, 55 = 25,518; p < 0,001), de frequências (F2, 110 = 172,288; p < 0,001) e de interação entre frequências x condições x participantes (F8, 110 = 26,806; p < 0,001). Este estudo preliminar sugere alterações na FSC relacionadas à ingestão moderada de álcool(AU)


The aim of this study was to compare the visual perception of contrast in adults with no alcohol intake, and after moderate consumption of alcohol by them – 0.09% Blood Alcohol Concentration (BAC), through the Contrast Sensitivity Function (CSF). Participated in the experiments five volunteers, aged 21-30 years, with normal or corrected visual acuity. To measure the CSF, we used radial sine-wave grating stimuli of frequencies of 0.25; 2 e 8 cycles per degree of visual angle. We used an experimental design or sketch, with repeated measures, and a forced-choice psychophysical method. The results showed significant effect of subjects (F4, 55 = 25,518; p < 0,001), of frequencies (F2, 110 = 172,288; p < 0,001), and of the interaction between frequencies versus conditions versus subjects (F8, 110 = 26,806; p < 0,001). This preliminary study suggests changes in CSF, related to moderate alcohol consumption(AU)


L'objectif de cette étude était comparer la perception visuelle de contraste chez des adultes sans consommation d'alcool et, dans le cas d'autres, après une consommation modérée d'alcool – 0,09% taux d'alcoolémie (TA), grâce à la fonction de sensibilité au contraste (FSC). Cinq volontaires — âgés de 21-30 ans et avec d'acuité visuelle normale ou corrigée — ont participé aux expériences. Pour mesurer la FSC, nous avons utilisé la grille sinusoïdale radiale de 0,25; 2 et 8 cycles par degré de l'angle visuel. Nous avons utilisé aussi un modèle expérimental, avec des mesures répétées, et une méthode psychophysique de choix forcé. Les résultats ont montré d'effet significatif dans les sujets (F4, 55 = 25,518; p < 0,001), dans les fréquences (F2, 110 = 172,288; p < 0,001) et dans l'interaction entre les fréquences, les conditions et les sujets (F8, 110 = 26,806; p < 0,001). Cette étude préliminaire suggère des changements dans la FSC, liés à la consommation modérée d'alcool(AU)


El objetivo de este estudio fue comparar la percepción visual de contraste en los adultos, sin consumo de alcohol y después de un consumo moderado de alcohol por parte de ellos – 0,09% de concentración de alcohol en sangre (BAC), a través de la función de sensibilidad al contraste (CSF). Participaron en los experimentos cinco voluntarias, con edades entre 21 y 30 años, con valores normales de agudeza visual. Para medir la CSF, se utilizaron radiales de onda sinusoidal rejilla de estímulos de frecuencias de 0,25, 2 e 8 ciclos por grado de ángulo visual. Se utilizó un diseño experimental o croquis, con medidas repetidas y un método psicofísico de la elección forzada. Los resultados mostraron efecto significativo de sujetos (F4, 55 = 25.518, p < 0.001), de las frecuencias (F2, 110 = 172.288, p < 0,001) y de la interacción entre las frecuencias en comparación con las condiciones en comparación con sujetos (F8, 110 = 26,806; p < 0,001). Este estudio preliminar sugiere cambios en el LCR, relacionados con el consumo moderado de alcohol(AU)


Asunto(s)
Humanos , Femenino , Adulto , Percepción Visual , Consumo de Bebidas Alcohólicas/psicología , Sensibilidad de Contraste
16.
Psicol. USP ; 22(1): 99-116, 2011. ilus
Artículo en Portugués | LILACS | ID: lil-582671

RESUMEN

O objetivo deste trabalho foi comparar a percepção visual de contraste de adultos sem a ingestão de álcool e após a ingestão moderada de álcool - 0,09 por cento Blood Alcohol Concentration (BAC), através da Função de Sensibilidade ao Contraste (FSC). Participaram dos experimentos cinco voluntárias, na faixa etária de 21 a 30 anos, com acuidade visual normal ou corrigida. Para medir a FSC, foram usados estímulos de grade senoidal radial de frequências de 0,25; 2 e 8 ciclos por grau de ângulo visual. Utilizou-se um delineamento experimental com medidas repetidas e o método psicofísico da escolha forçada. Os resultados demonstraram efeito significante de participantes (F4, 55 = 25,518; p < 0,001), de frequências (F2, 110 = 172,288; p < 0,001) e de interação entre frequências x condições x participantes (F8, 110 = 26,806; p < 0,001). Este estudo preliminar sugere alterações na FSC relacionadas à ingestão moderada de álcool.


The aim of this study was to compare the visual perception of contrast in adults with no alcohol intake, and after moderate consumption of alcohol by them - 0.09 percent Blood Alcohol Concentration (BAC), through the Contrast Sensitivity Function (CSF). Participated in the experiments five volunteers, aged 21-30 years, with normal or corrected visual acuity. To measure the CSF, we used radial sine-wave grating stimuli of frequencies of 0.25; 2 e 8 cycles per degree of visual angle. We used an experimental design or sketch, with repeated measures, and a forced-choice psychophysical method. The results showed significant effect of subjects (F4, 55 = 25,518; p < 0,001), of frequencies (F2, 110 = 172,288; p < 0,001), and of the interaction between frequencies versus conditions versus subjects (F8, 110 = 26,806; p < 0,001). This preliminary study suggests changes in CSF, related to moderate alcohol consumption.


L'objectif de cette étude était comparer la perception visuelle de contraste chez des adultes sans consommation d'alcool et, dans le cas d'autres, après une consommation modérée d'alcool - 0,09 percent taux d'alcoolémie (TA), grâce à la fonction de sensibilité au contraste (FSC). Cinq volontaires —âgés de 21-30 ans et avec d'acuité visuelle normale ou corrigée —ont participé aux expériences. Pour mesurer la FSC, nous avons utilisé la grille sinusoïdale radiale de 0,25; 2 et 8 cycles par degré de l'angle visuel. Nous avons utilisé aussi un modèle expérimental, avec des mesures répétées, et une méthode psychophysique de choix forcé. Les résultats ont montré d'effet significatif dans les sujets (F4, 55 = 25,518; p < 0,001), dans les fréquences (F2, 110 = 172,288; p < 0,001) et dans l'interaction entre les fréquences, les conditions et les sujets (F8, 110 = 26,806; p < 0,001). Cette étude préliminaire suggère des changements dans la FSC, liés à la consommation modérée d'alcool.


El objetivo de este estudio fue comparar la percepción visual de contraste en los adultos, sin consumo de alcohol y después de un consumo moderado de alcohol por parte de ellos - 0,09 por ciento de concentración de alcohol en sangre (BAC), a través de la función de sensibilidad al contraste (CSF). Participaron en los experimentos cinco voluntarias, con edades entre 21 y 30 años, con valores normales de agudeza visual. Para medir la CSF, se utilizaron radiales de onda sinusoidal rejilla de estímulos de frecuencias de 0,25, 2 e 8 ciclos por grado de ángulo visual. Se utilizó un diseño experimental o croquis, con medidas repetidas y un método psicofísico de la elección forzada. Los resultados mostraron efecto significativo de sujetos (F4, 55 = 25.518, p < 0.001), de las frecuencias (F2, 110 = 172.288, p < 0,001) y de la interacción entre las frecuencias en comparación con las condiciones en comparación con sujetos (F8, 110 = 26,806; p < 0,001). Este estudio preliminar sugiere cambios en el LCR, relacionados con el consumo moderado de alcohol.

17.
Psicol. USP ; 22(1): 81-98, 2011. ilus
Artículo en Portugués | LILACS | ID: lil-582673

RESUMEN

O objetivo foi medir a Função de Sensibilidade ao Contraste (FSC) de pacientes com migrânea e de voluntários saudáveis sem a patologia. Participaram dos testes 12 voluntários do sexo feminino, seis com migrânea e seis sem migrânea na faixa etária de 20 a 37 anos. As medidas de FSC foram realizadas utilizando estímulos visuais estáticos de grades senoidais angulares com frequências espaciais de 2, 3, 4, 24 e 64 ciclos/360º Foi utilizado o método psicofísico da escolha forçada entre duas alternativas temporais, condições de luminância fotópica (luminância média da tela de 41 cd/m²) e visão binocular com pupila natural. Os resultados demonstram que a percepção visual de contraste dos voluntários com migrânea foi menor nas frequências de 2, 3, 4 e 64 ciclos/360º. Esses achados preliminares sugerem alterações na FSC relacionadas a essa patologia.


In this work, the aim was to measure the Contrast Sensitivity Function (CSF) among patients with, and healthy volunteers without this pathology. The subjects of the tests were 12 female volunteers, aged 20-37 years - six of them with migraine, and six other ones without migraine. CSF measurements were performed using static visual stimuli of angular sine-wave gratings, with spatial frequencies of 2, 3, 4, 24 and 64 cycles/360º. Method used was the psychophysical one, with forced choice between two temporal alternatives, conditions of photopic luminance (screen average luminance of 41 cd/m²), and binocular vision with natural pupil. The results demonstrate that visual perception of contrast by the volunteers with migraine was lower in the frequencies of 2, 3, 4 and 64 cycles/360°. These preliminary findings suggest changes in the CSF related to this pathology.


Dans ce travail, l'objectif était celui de mesurer la Fonction de Sensibilité au Contraste (FSC) chez des patients souffrant de migraine et des volontaires sains sans cette pathologie. Ont participé des tests 12 volontaires du sexe féminin, âgées de 20-37 ans, six avec de la migraine et six sans migraine. Les mesures de FSC ont été réalisées avec des stimuli visuels statiques des grilles d'ondes sinusoïdales angulaires, avec des fréquences spatiales de 2, 3, 4, 24 et 64 cycles/360º. La méthode utilisée a été la psychophysique, avec choix forcé entre deux alternatives temporelles, les conditions de luminosité photopique (luminance moyenne par écran de 41 cd/m²) et la vision binoculaire avec des pupilles naturelles. Les résultats démontrent que la perception visuelle de contraste par les volontaires souffrant de migraine a été plus faible dans les fréquences de 2, 3, 4 et 64 cycles/360°. Ces résultats préliminaires suggèrent des changements dans le FSC liés à cette pathologie.


En este trabajo, el objetivo era medir la función de sensibilidad al contraste (CSF) en pacientes con y voluntarios sanos sin esta patología. Los sujetos de los ensayos fueron 12 mujeres voluntarias, con edades entre 20-37 años - seis de ellos con la migraña, y seis otros sin migraña. Mediciones LCR se realizaron mediante estímulos visuales estáticos de rejilla angular de onda sinusoidal, con frecuencias espaciales de 2, 3, 4, 24 y 64º cycles/360. El método utilizado fue el psicofísico con elección forzada entre dos alternativas temporales, las condiciones de luminosidad fotópica (luminancia de pantalla media de 41 cd / m²) y la visión binocular con pupila natural. Los resultados demuestran que la percepción visual de contraste por los voluntarios con migraña fue menor en las frecuencias de 2, 3, 4 y 64 cycles/360°. Estos hallazgos preliminares sugieren cambios en el LCR en relación aesta patología.

18.
Psicol. teor. pesqui ; 25(2): 189-194, abr.-jun. 2009. ilus
Artículo en Portugués | Index Psicología - Revistas | ID: psi-44022

RESUMEN

O objetivo deste trabalho foi medir curvas de sensibilidade ao contraste de 10 crianças ouvintes e de 10 crianças com surdez pré-lingual, de 7 a 12 anos, utilizando frequências radiais circularmente concêntricas (FSCr) de 0,25-2,0 cpg em níveis baixos de luminância (0,7 cd/m²). Todos os participantes apresentavam acuidade visual normal e estavam livres de doenças oculares identificáveis. A FSCr foi medida com o método psicofísico da escolha forçada. Os resultados mostraram sensibilidade máxima na faixa de frequência radial de 0,25 cpg para os dois grupos. Os resultados mostraram ainda diferenças significantes entre as curvas de FSCr de crianças ouvintes e de crianças com surdez pré-lingual. Isto é, as crianças ouvintes precisaram de menos contraste do que as crianças surdas para detectar as frequências radiais. Esses resultados sugerem que, em níveis baixos de luminância, a FSCr das crianças ouvintes foi melhor do que a das crianças com surdez pré-lingual.(AU)


The aim of this work was to measure contrast sensitivity curves in 10 hearing children and 10 children with prelingual deafness (from 7 to 12 years old), using concentric circular patterns with radial frequencies (rCSF) of 0.25-2.0 cpd at low levels of luminance (0.7 cd/m²). All participants were free from identifiable ocular disease and had normal visual acuity. The rCSF was measured with the psychophysical forced-choice method. The results showed maximum sensitivity in the frequency range of 0.25 cpd for the two groups. The results showed yet significant differences between the rCSF of deaf and hearing children. That is, hearing children needed less contrast than deaf children to detect radial frequencies. These results suggest that at low levels of luminance the rCSF of hearing children was better than the rCSF of children with prelingual deafness.(AU)


Asunto(s)
Percepción Visual , Personas con Deficiencia Auditiva
19.
Psico (Porto Alegre) ; 40(2): 227-234, abr.-jun. 2009.
Artículo en Portugués | Index Psicología - Revistas | ID: psi-45145

RESUMEN

O objetivo deste estudo foi medir e comparar as curvas de sensibilidade ao contraste mesópicas para estímulos radiais (FSCr) e grades senoidais (FSC) de 0,25; 0,5; 1 e 2 cpg em crianças surdas de 7 a 12 anos. Mensuramos limiares de contraste para 10 crianças, utilizando o método psicofísico da escolha forçada e luminância média de 0,7 cd/m2. Todos os participantes estavam livres de doenças oculares e apresentavam acuidade visual normal. Os resultados mostraram que a sensibilidade das crianças surdas foi maior para grades senoidais (FSC) do que para estímulos radiais (FSCr). Estes resultados sugerem que os dois estímulos podem ser processados por áreas visuais corticais distintas.(AU)


The aim of this work was to measure and compare mesopic contrast sensitivity curves for radial (rCSF) and sine-wave gratings (CSF) stimuli of 0.25, 0.5, 1 and 2 cpd in deaf children between the ages of 7 to 12 years. We measured the contrast thresholds of 10 children using the psychophysical forced-choice method and mean luminance of 0.7 cd/m2. All participants were free of ocular diseases and had normal acuity. The results showed that contrast sensitivity of the deaf children was higher for sine-wave gratings (CSF) than radial stimuli (rCSF). These results suggest that these two stimuli can be processed by different visual cortical areas.(AU)


El objetivo de este estudio fue medir y comparar las curvas de sensibilidad al contraste mesópicas para estímulos radiales (FSCr) y rejillas sinusoidales (FSC) de 0,25; 0,5; 1 y 2 cpg en niños sordos de 7 a 12 años. Medimos los umbrales de contraste en 10 niños, con el método psicofísico de la elección forzada y la luminancia media de 0,7 cd/m2. Todos los participantes estaban libres de enfermedades oculares y presentaban acuidad visual normal. Los resultados mostraron que la sensibilidad de los niños sordos fue mayor para frecuencias espaciales (FSC) que para los estímulos radiales (FSCr). Estos resultados sugieren que los estímulos pueden ser procesados en distintas areas corticales visuales.(AU)


Asunto(s)
Humanos , Masculino , Niño , Percepción Visual , Sordera
20.
Psico (Porto Alegre) ; 40(2): 227-234, abr.-jun. 2009.
Artículo en Portugués | LILACS | ID: lil-539637

RESUMEN

O objetivo deste estudo foi medir e comparar as curvas de sensibilidade ao contraste mesópicas para estímulos radiais (FSCr) e grades senoidais (FSC) de 0,25; 0,5; 1 e 2 cpg em crianças surdas de 7 a 12 anos. Mensuramos limiares de contraste para 10 crianças, utilizando o método psicofísico da escolha forçada e luminância média de 0,7 cd/m2. Todos os participantes estavam livres de doenças oculares e apresentavam acuidade visual normal. Os resultados mostraram que a sensibilidade das crianças surdas foi maior para grades senoidais (FSC) do que para estímulos radiais (FSCr). Estes resultados sugerem que os dois estímulos podem ser processados por áreas visuais corticais distintas.


The aim of this work was to measure and compare mesopic contrast sensitivity curves for radial (rCSF) and sine-wave gratings (CSF) stimuli of 0.25, 0.5, 1 and 2 cpd in deaf children between the ages of 7 to 12 years. We measured the contrast thresholds of 10 children using the psychophysical forced-choice method and mean luminance of 0.7 cd/m2. All participants were free of ocular diseases and had normal acuity. The results showed that contrast sensitivity of the deaf children was higher for sine-wave gratings (CSF) than radial stimuli (rCSF). These results suggest that these two stimuli can be processed by different visual cortical areas.


El objetivo de este estudio fue medir y comparar las curvas de sensibilidad al contraste mesópicas para estímulos radiales (FSCr) y rejillas sinusoidales (FSC) de 0,25; 0,5; 1 y 2 cpg en niños sordos de 7 a 12 años. Medimos los umbrales de contraste en 10 niños, con el método psicofísico de la elección forzada y la luminancia media de 0,7 cd/m2. Todos los participantes estaban libres de enfermedades oculares y presentaban acuidad visual normal. Los resultados mostraron que la sensibilidad de los niños sordos fue mayor para frecuencias espaciales (FSC) que para los estímulos radiales (FSCr). Estos resultados sugieren que los estímulos pueden ser procesados en distintas areas corticales visuales.


Asunto(s)
Humanos , Masculino , Niño , Sordera , Percepción Visual
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...