997 resultados para publishers
Resumo:
Recent studies have revealed regional variation in the density and distribution of inhibitory neurons in different cortical areas, which are thought to reflect area-specific specializations in cortical circuitry. However, there are as yet few standardized quantitative data regarding how the inhibitory circuitry in prefrontal cortex (PFC), which is thought to be involved in executive functions such as cognition, emotion and decision making, compares to that in other cortical areas. Here we used immunohistochemical techniques to determine the density and distribution of parvalbumin (PV)-, calbindin (CB)-, and calretinin (CR)-immunoreactive (ir) neurons and axon terminals in the dorsolateral and orbital PFC of the owl monkey (Aotus trivirgatus), and compared them directly with data obtained using the same techniques in 11 different visual, somatosensory and motor areas. We found marked differences in the density of PV-ir, CB-ir, and CR-ir interneurons in several cortical areas. One hundred and twenty eight of all 234 possible between-area pairwise comparisons were significantly different. The density of specific subpopulations of these cells also varied among cortical areas, as did the density of axon terminals. Comparison of PFC with other cortical areas revealed that 40 of all 66 possible statistical comparisons of the density of PV-ir, CB-ir, and CR-ir cells were significantly different. We also found evidence for heterogeneity in the pattern of labeling of PV-ir, CB-ir, and CR-ir cells and axon terminals between the dorsolateral and orbital subdivisions of PFC. These data are likely to reflect basic differences in interneuron circuitry, which are likely to influence inhibitory function in the cortex. Copyright (C) 2003 S. Karger AG, Basel.
Resumo:
Color model representation allows characterizing in a quantitative manner, any defined color spectrum of visible light, i.e. with a wavelength between 400nm and 700nm. To accomplish that, each model, or color space, is associated with a function that allows mapping the spectral power distribution of the visible electromagnetic radiation, in a space defined by a set of discrete values that quantify the color components composing the model. Some color spaces are sensitive to changes in lighting conditions. Others assure the preservation of certain chromatic features, remaining immune to these changes. Therefore, it becomes necessary to identify the strengths and weaknesses of each model in order to justify the adoption of color spaces in image processing and analysis techniques. This chapter will address the topic of digital imaging, main standards and formats. Next we will set the mathematical model of the image acquisition sensor response, which enables assessment of the various color spaces, with the aim of determining their invariance to illumination changes.
Resumo:
Nanotechnology is the manipulation of matter on na almost atomic scale to produce new structures, materials, and devices. As potential occupational exposure to nanomaterials (NMs) becomes more prevalente, it is importante that the principles of medical surveillance and risk management be considered for workers in the nanotechnology industry.However, much information about health risk is beyond our current knowledge. Thus, NMs presente new challenges to understanding, predicting, andmanageing potential health risks. First, we briefly describe some general features of NMs and list the most importante types of NMs. This review discusses the toxicological potential of NMs by comparing possible injury mechanism and know, or potentially adverse, health effects. We review the limited research to date for occupational exposure to these particles and how a worker might be exposed to NMs. The principles of medical surveillance are reviewed to further the discussion of occupational health surveillance are reviewed to further the discussion of occupational health surveillance for workers exposed to NMs. We outlinehow occupational health professionals could contribute to a better knowledge of health effects by the utilization of a health surveillance program and by minimizing exposure. Finally, we discuss the early steps towards regulation and the difficulties facing regulators in controlling potentially harmful exposures in the absence of suficiente scientific evidence.
Resumo:
“Responsabilidade Financeira e Criminal § Direitos Constitucionais Sociais, Dinheiros Públicos e Recuperação de Activos”, com Prefácio do Sr. Prof. Associado com Agregação, da Faculdade de Direito da Universidade de Coimbra, Doutor Jónatas E.M. Machado, é o título e tema do nosso último livro jurídico dado à estampa pela chancela da Editora Juruá, Curitiba e Lisboa, 2015. Livro o qual está disponível em Portugal nas livrarias Almedina ou em inúmeras livrarias do Brasil. Ou ainda através da loja virtual daquela que é uma das maiores editoras do mundo em língua portuguesa, a Editora Juruá que tem mais de 46 anos de vida: www.jurua.com.br § "Financial Responsibility and Criminal § Constitutional Social Rights, Public Moneys and Assets Recovery" with Prof. Mr. Preface Associated with aggregation, the Law Faculty of the University of Coimbra, Doctor Jónatas E.M. Machado is the title and theme of our last legal book given to the press by the seal of Editora Jurua, Curitiba and Lisbon, 2015. Book which is available in Portugal Almedina in bookstores or in several bookstores in Brazil. Or through the online store of what is one of the largest publishers in the world in English, Editora Jurua which has more than 46 years: www.jurua.com.br
Resumo:
In this paper we present results on the optimization of multilayered a-SiC:H heterostructures that can be used as optical transducers for fluorescent proteins detection using the Fluorescence Resonance Energy Transfer approach. Double structures composed by pin based aSiC:H cells are analyzed. The color discrimination is achieved by ac photocurrent measurement under different externally applied bias. Experimental data on spectral response analysis, current-voltage characteristics and color and transmission rate discrimination are reported. An electrical model, supported by a numerical simulation gives insight into the device operation. Results show that the optimized a-SiC:H heterostructures act as voltage controlled optical filters in the visible spectrum. When the applied voltages are chosen appropriately those optical transducers can detect not only the selective excitation of specimen fluorophores, but also the subsequent weak acceptor fluorescent channel emission.