Developmental changes in the cone visual pigments of black bream Acanthopagrus butcheri

The spectral absorption characteristics of the visual pigments in the photoreceptors of the black bream Acanthopagrus butcheri Munro (Sparidae, Teleostei), were measured using microspectrophotometry. A single cohort of fish aged 5-172 days post-hatch (dph), aquarium-reared adults and wild-caught juveniles were investigated. During the larval stage and in juveniles younger than 100 dph, two classes of visual pigment were found, with wavelengths of maximum absorbance (lambda(max)) at approximately 425 nm and 535 nm. Following double cone formation, from 40 dph onwards, the short wavelength-sensitive pigment was recorded in single cones and the longer wavelength-sensitive pigment in double cones. From 100 dph, a gradual shift in the lambda(max) towards longer wavelengths was observed in both cone types. By 160 dph, and in adults, all single cones had a lambda(max) at approximately 475 nm while the lambda(max) in double cones ranged from 545 to 575 nm. The relationships between the lambda(max) and the ratio of bandwidth:lambda(max), for changes in either chromophore or opsin, were modelled mathematically for the long-wavelength-sensitive visual pigments. Comparing our data with the models indicated that changes in lambda(max) were not mediated by a switch from an A(1) to A(2) chromophore, rather a change in opsin expression was most likely. The shifts in the lambda(max) of the visual pigments occur at a stage when the juvenile fish begin feeding in deeper, tannin-stained estuarine waters, which transmit predominantly longer wavelengths, so the spectral sensitivity changes may represent an adaptation by the fish to the changing light environment.

Characterisation of chronic lateral epicondylalgia using the McGill pain questionnaire, visual analog scales, and quantitative sensory tests

Aims: To characterise chronic lateral epicondylalgia using the McGill Pain Questionnaire, Visual Analog Scales for pain and function, and Quantitative Sensory Tests; and to examine the relationship between these tests in a population with chronic lateral epicondylalgia. Method: Fifty-six patients (29 female, 27 male) diagnosed with unilateral lateral epicondylalgia of 18.7 months (mean) duration (range 1-300), with a mean age of 50.7 years (range 27-73) participated in this study. Each participant underwent assessment with the McGill Pain Questionnaire (MPQ), Visual Analog Scales (VAS) for pain and function. and Quantitative Sensory Tests (QST) including thermal and pressure pain thresholds, pain free grip strength, and neuromeningeal tissue testing via the upper limb tension test 2b (ULTT 2b). Results: Moderate correlation (r = .338-.514, p = .000-.013) was found between all indices of the MPQ and VAS for pain experienced in the previous 24 hours and week. Thermal pain threshold was found to be significantly higher in males. A significant poor to moderate correlation was found between the Pain Rating Index (PRI) in the sensory category of the MPQ and ULTT2b scores (r = .353, p = .038). There was no other significant correlation between MPQ and QST data. Pain free grip strength was poorly yet significantly correlated with duration of pathology (r = 318, p = .038). Conclusion: The findings of this study are in agreement with others (Melzack and Katz, 1994) regarding the multidimensional nature of pain, in a condition conventionally conceived as a musculoskeletal pain state. The findings also suggest that utilisation of only one pain measurement tool is unlikely to provide a thorough clinical picture of pain experienced with chronic lateral epicondylalgia.

Conspicuous males suffer higher predation risk: visual modelling and experimental evidence from lizards

Colour pattern variation is a striking and widespread phenomenon. Differential predation risk between individuals is often invoked to explain colour variation, but empirical support for this hypothesis is equivocal. We investigated differential conspicuousness and predation risk in two species of Australian rock dragons, Ctenophorus decresii and C. vadnappa. To humans, the coloration of males of these species varies between 'bright' and 'dull'. Visual modelling based on objective colour measurements and the spectral sensitivities of avian visual pigments showed that dragon colour variants are differentially conspicuous to the visual system of avian predators when viewed against the natural background. We conducted field experiments to test for differential predation risk, using plaster models of 'bright' and 'dull' males. 'Bright' models were attacked significantly more often than 'dull' models suggesting that differential conspicuousness translates to differential predation risk in the wild. We also examined the influence of natural geographical range on predation risk. Results from 22 localities suggest that predation rates vary according to whether predators are familiar with the prey species. This study is among the first to demonstrate both differential conspicuousness and differential predation risk in the wild using an experimental protocol. (C) 2003 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour.

Visual Biology of Hawaiian Coral Reef Fishes. III. Environmental Light and an Integrated Approach to the Ecology of Reef Fish Vision

In the previous two papers in this three-part series, we have examined visual pigments, ocular media transmission, and colors of the coral reef fish of Hawaii. This paper first details aspects of the light field and background colors at the microhabitat level on Hawaiian reefs and does so from the perspective and scale of fish living on the reef. Second, information from all three papers is combined in an attempt to examine trends in the visual ecology of reef inhabitants. Our goal is to begin to see fish the way they appear to other fish. Observations resulting from the combination of results in all three papers include the following. Yellow and blue colors on their own are strikingly well matched to backgrounds on the reef such as coral and bodies of horizontally viewed water. These colors, therefore, depending on context, may be important in camouflage as well as conspicuousness. The spectral characteristics of fish colors are correlated to the known spectral sensitivities in reef fish single cones and are tuned for maximum signal reliability when viewed against known backgrounds. The optimal positions of spectral sensitivity in a modeled dichromatic visual system are generally close to the sensitivities known for reef fish. Models also predict that both UV-sensitive and red-sensitive cone types are advantageous for a variety of tasks. UV-sensitive cones are known in some reef fish, red-sensitive cones have yet to be found. Labroid colors, which appear green or blue to us, may he matched to the far-red component of chlorophyll reflectance for camouflage. Red cave/hole dwelling reef fish are relatively poorly matched to the background they are often viewed against but this may be visually irrelevant. The model predicts that the task of distinguishing green algae from coral is optimized with a relatively long wavelength visual pigment pair. Herbivorous grazers whose visual pigments are known possess the longest sensitivities so far found. Labroid complex colors are highly contrasting complementary colors close up but combine, because of the spatial addition, which results from low visual resolution, at distance, to match background water colors remarkably well. Therefore, they are effective for simultaneous communication and camouflage.

Pyramidal cell heterogeneity in the visual cortex of the nocturnal new world owl monkey (aotus trivirgatus)

Recent studies have revealed marked variation in pyramidal cell structure in the visual cortex of macaque and marmoset monkeys. In particular, there is a systematic increase in the size of, and number of spines in, the arbours of pyramidal cells with progression through occipitotemporal (OT) visual areas. In the present study we extend the basis for comparison by investigating pyramidal cell structure in visual areas of the nocturnal owl monkey. As in the diurnal macaque and marmoset monkeys, pyramidal cells became progressively larger and more spinous with anterior progression through OT visual areas. These data suggest that: 1. the trend for more complex pyramidal cells with anterior progression through OT visual areas is a fundamental organizational principle in primate cortex; 2. areal specialization of the pyramidal cell phenotype provides an anatomical substrate for the reconstruction of the visual scene in OT areas; 3. evolutionary specialization of different aspects of visual processing may determine the extent of interareal variation in the pyramidal cell phenotype in different species; and 4. pyramidal cell structure is not necessarily related to brain size. Crown Copyright (C) 2003 Published by Elsevier Science Ltd on behalf of IBRO. All rights reserved.

Dendritic branching of pyramidal cells in the visual cortex of the nocturnal owl monkey: A fractal analysis

The branching structure of neurones is thought to influence patterns of connectivity and how inputs are integrated within the arbor. Recent studies have revealed a remarkable degree of variation in the branching structure of pyramidal cells in the cerebral cortex of diurnal primates, suggesting regional specialization in neuronal function. Such specialization in pyramidal cell structure may be important for various aspects of visual function, such as object recognition and color processing. To better understand the functional role of regional variation in the pyramidal cell phenotype in visual processing, we determined the complexity of the dendritic branching pattern of pyramidal cells in visual cortex of the nocturnal New World owl monkey. We used the fractal dilation method to quantify the branching structure of pyramidal cells in the primary visual area (V1), the second visual area (V2) and the caudal and rostral subdivisions of inferotemporal cortex (ITc and ITr, respectively), which are often associated with color processing. We found that, as in diurnal monkeys, there was a trend for cells of increasing fractal dimension with progression through these cortical areas. The increasing complexity paralleled a trend for increasing symmetry. That we found a similar trend in both diurnal and nocturnal monkeys suggests that it was a feature of a common anthropoid ancestor.

Boletim eletr??nico de bibliografias especializadas: igualdade racial

Indicadores socioecon??micos apontam que as expressivas diferen??as raciais existentes no Brasil t??m reflexos na educa????o, sa??de, renda, viol??ncia, expectativa de vida etc. Diante desse conjunto cada vez mais evidente de desigualdades, o debate p??blico sobre essa tem??tica tem se intensificado, assim como as iniciativas no campo das pol??ticas p??blicas. A Organiza????o Internacional do Trabalho (OIT) afirma que, para combater o comportamento social provocado pelo racismo, ?? necess??rio demonstrar sua exist??ncia e os mecanismos pelos quais ele opera. Tendo em vista tal conjuntura, o presente Boletim divulga as publica????es do acervo da Biblioteca Graciliano Ramos, da ENAP, que trazem contribui????es ao tema da Igualdade Racial

Confer??ncias nacionais de sa??de e processos participativos na administra????o p??blica federal brasileira

Este caso aborda as Confer??ncias Nacionais de Sa??de (CNS) enquanto espa??os institucionais leg??timos de participa????o social que contribuem para a emerg??ncia de uma governan??a apoiada em cidadania mais engajada e ativa. O estudo de caso pretende fomentar o debate sobre a emerg??ncia de novos padr??es de rela????o entre o Estado e sociedade, e sobre o avan??o da resili??ncia nas organiza????es sociais e nas institui????es p??blicas. Pretende tamb??m levantar os novos desafios colocados para os gestores p??blicos com a amplia????o da participa????o e diversidade dos atores, al??m de maior especificidade das demandas, o que gera maiores dificuldades na obten????o de consensos e na elei????o de prioridades. O caso pode ser aplicado em cursos que abordem tem??ticas relacionadas ?? participa????o social, redes sociais, governan??a, democracia e pol??ticas p??blicas

Texto para discuss??o 5: reforma administrativa e direito adquirido ao regime da fun????o p??blica

O direito adquirido tem sido argumento freq??entemente invocado pelos opositores da reforma constitucional do aparelho administrativo do Estado. Nesse debate, entretanto, este argumento ?? completamente destitu??do de validade t??cnica. Dizer que a reforma constitucional n??o pode alterar o regime jur??dico dos servidores p??blicos (o estatuto jur??dico da estabilidade, disponibilidade, remunera????o etc.) ?? incorrer em completo equ??voco. As raz??es dessa incompreens??o decorrem do desconhecimento de no m??nimo dois t??picos relevantes encartados no tema, a saber: a) a natureza do regime jur??dico que vincula o servidor p??blico civil ?? administra????o; e b) a distin????o entre efic??cia imediata e efic??cia retroativa das normas constitucionais

Comprasnet: o site da transpar??ncia das compras governamentais

O Site www.comprasnet.gov.br, utilizando recurso da Internet, est?? definindo novas estrat??gias para as Compras Governamentais. Entre as funcionalidades existentes, os usu??rios do governo, fornecedores e a sociedade contam com os seguintes servi??os: Legisla????o: trata dos assuntos legais pertinentes, Publica????es: voltado ??s not??cias de interesse comum entre os usu??rios; Servi??os de Livre Acesso: disponibiliza, entre outros, o SICAFWEB, Preg??o Eletr??nico, Consulta Licita????o; Servi??os por Assinatura: agrega valores para atender necessidades espec??ficas dos usu??rios cadastrados. Exemplo: Consulta Licita????es com acesso a itens e editais, Listas Preferenciais, etc. e, o SIASG que concentra F??rum de Discuss??o, Consultas Gerenciais, Homologa????o de Preg??o Eletr??nico, al??m dos diversos m??dulos que o comp??em

Texto para discuss??o 15: cidadania e res publica: a emerg??ncia dos direitos republicanos

O trabalho concentra no processo civilizat??rio mais geral, de natureza pol??tica, pelo qual os homens e mulheres v??m buscando a ordem, a liberdade e a justi??a social. Para isto, partindo da proposta b??sica de Marshall,o texto examinar?? o desenvolvimento da id??ia de cidadania a partir da afirma????o, primeiro, dos direitos civis, segundo, dos direitos pol??ticos, e terceiro, dos direitos sociais. ?? medida, entretanto, que esses direitos, ainda que n??o tenham sido efetivamente assegurados, j?? foram razoavelmente bem definidos e incorporados nas constitui????es e nas leis dos pa??ses civilizados, o artigo argumentar?? que, no ??ltimo quartel do s??culo XX, um quarto direito de cidadania ??? os direitos p??blicos ou, mais precisamente, os direitos republicanos ??? est?? sendo definido e precisa ser melhor positivado e efetivamente garantido. Definir?? os direitos republicanos como os direitos que todo cidad??o tem de que o patrim??nio p??blico ??? seja ele o patrim??nio hist??rico-cultural, seja o patrim??nio ambiental, seja o patrim??nio econ??mico ou res publica estrito senso ??? seja efetivamente p??blico, ou seja, de todos e para todos. O texto procura, especialmente, entre os direitos republicanos, propor uma defini????o para o direito ?? res publica ou ?? ???coisa p??blica???, entendida esta, de forma restrita, como o estoque de ativos e principalmente o fluxo de recursos que o Estado e as entidades p??blicas n??o-estatais controlam