Geometric Quantization of Topological Gauge Theories

We study the symplectic quantization of Abelian gauge theories in $2+1$ space-time dimensions with the introduction of a topological Chern-Simons term.Comment: 13 pages, plain TEX, IF/UFRJ/9

Identification of common bean resistant sources to angular leaf spot disease in a brazilian germplasm collection.

The aim of this study was to identify sources of resistance in the germplasm collection providing information of potential sources of resistance to introduce in breeding programs

Sintomas osteomusculares e desempenho ocupacional: um estudo entre músicos instrumentistas no contexto do Distrito Federal, Brasil.

Objetivo: Determinar a prevalência de sintomatologia osteomuscular entre músicos de uma universidade federal, verificando seu impacto sobre a participação em atividades de vidadiária e o desempenho de atividades laborais. Método: 26 músicos foram avaliados por meio do Questionário de Disfunção do Ombro, Braço e Mão e Questionário Nórdico de Sintomas Osteomusculares. A relação entre sintomatologia musculoesquelética e desempenho ocupacional foi avaliada por meio dos testes de Mann-Whitney, Teste de Correlação de Spearman e Teste de Chi-Quadrado. Resultados: Foi observado predomínio de queixas osteomusculares nas regiões dos membros superiores e tronco, com baixa procura dos músicos por tratamentos de saúde. Observaram-se diferenças significativas no desempenho de atividades de vida diária e realização de atividades relacionadas à prática musical entre participantes que apresentavam queixas osteomusculares em membros superiores. Conclusão: O desempenho da atividade musical pode levar a processos de adoecimento, influenciando as atividades laborais, e outras áreas do desempenho ocupacional.Ações voltadas para a prevenção e tratamento de queixas osteomusculares são importantes para a elaboração de estratégias que visam preservar e promover a saúde desta população.Objective: To determine the prevalence of musculoskeletal symptomatology among musicians from a federal university, verifying its impact on daily activities and work performance. Methods: 26 musicians have been assessed using the Disabilities of the Arm, Shoulder, and Hand Questionnaire and the Nordic Musculoskeletal Questionnaire. Relation between musculoskeletal symptomatology and occupational performance was evaluated by Mann-Whitney test, Spearman’s rank correlation coefficient, and Chi-square test. Results: We observed preponderance of musculoskeletal complaints in the upper limbs and torso regions, with low demand for medical services by musicians. There was significant difference in the performance of daily activities and music practice among participants who had musculoskeletalcomplaints in upper limbs. Conclusion: Playing-related musculoskeletal disorders may affect work activities and other areas of occupational performance. Initiatives on prevention and treatment of musculoskeletal disorders are important to the development of strategies aiming at preserving and promoting this population health

Pattern Recognition in Macroscopic and Dermoscopic Images for Skin Lesion Diagnosis

Pattern recognition in macroscopic and dermoscopic images is a challenging task in skin lesion diagnosis. The search for better performing classification has been a relevant issue for pattern recognition in images. Hence, this work was particularly focused on skin lesion pattern recognition, especially in macroscopic and dermoscopic images. For the pattern recognition in macroscopic images, a computational approach was developed to detect skin lesion features according to the asymmetry, border, colour and texture properties, as well as to diagnose types of skin lesions, i.e., nevus, seborrheic keratosis and melanoma. In this approach, an anisotropic diffusion filter is applied to enhance the input image and an active contour model without edges is used in the segmentation of the enhanced image. Finally, a support vector machine is used to classify each feature property according to their clinical principles, and also for the classification between different types of skin lesions. For the pattern recognition in dermoscopic images, classification models based on ensemble methods and input feature manipulation are used. The feature subsets was used to manipulate the input feature and to ensure the diversity of the ensemble models. Each ensemble classification model was generated by using an optimum-path forest classifier and integrated with a majority voting strategy. The performed experiments allowed to analyse the effectiveness of the developed approaches for pattern recognition in macroscopic and dermoscopic images, with the results obtained being very promising

Heterokaryon Incompatibility Is Suppressed Following Conidial Anastomosis Tube Fusion in a Fungal Plant Pathogen

It has been hypothesized that horizontal gene/chromosome transfer and parasexual recombination following hyphal fusion between different strains may contribute to the emergence of wide genetic variability in plant pathogenic and other fungi. However, the significance of vegetative (heterokaryon) incompatibility responses, which commonly result in cell death, in preventing these processes is not known. In this study, we have assessed this issue following different types of hyphal fusion during colony initiation and in the mature colony. We used vegetatively compatible and incompatible strains of the common bean pathogen Colletotrichum lindemuthianum in which nuclei were labelled with either a green or red fluorescent protein in order to microscopically monitor the fates of nuclei and heterokaryotic cells following hyphal fusion. As opposed to fusion of hyphae in mature colonies that resulted in cell death within 3 h, fusions by conidial anastomosis tubes (CAT) between two incompatible strains during colony initiation did not induce the vegetative incompatibility response. Instead, fused conidia and germlings survived and formed heterokaryotic colonies that in turn produced uninucleate conidia that germinated to form colonies with phenotypic features different to those of either parental strain. Our results demonstrate that the vegetative incompatibility response is suppressed during colony initiation in C. lindemuthianum. Thus, CAT fusion may allow asexual fungi to increase their genetic diversity, and to acquire new pathogenic traits

Hypotensive effect and endothelium-dependent vascular action of leaves of Alpinia purpurata (Vieill) K. Schum

The aims of this study were to evaluate the chemical profile, vascular reactivity, and acute hypotensive effect (AHE) of the ethanolic extract of leaves of Alpinia purpurata (Vieill) K. Schum (EEAP). Its chemical profile was evaluated using HPLC-UV, ICP-OES, and colorimetric quantification of total flavonoids and polyphenols. The vascular reactivity of the extract was determined using the mesenteric bed isolated from WKY. AHE dose-response curves were obtained for both EEAP and inorganic material isolated from AP (IAP) in WKY and SHR animals. Cytotoxic and mutagenic safety levels were determined by the micronucleus test. Rutin-like flavonoids were quantified in the EEAP (1.8 ± 0.03%), and the total flavonoid and polyphenol ratios were 4.1 ± 1.8% and 5.1 ± 0.3%, respectively. We observed that the vasodilation action of EEAP was partially mediated by nitric oxide (·NO). The IAP showed the presence of calcium (137.76 ± 4.08 μg mg-1). The EEAP and IAP showed an AHE in WKY and SHR animals. EEAP did not have cytotoxic effects or cause chromosomic alterations. The AHE shown by EEAP could result from its endothelium-dependent vascular action. Rutin-like flavonoids, among other polyphenols, could contribute to these biological activities, and the calcium present in EEAP could act in a synergistic way

Abundances of Iron-Binding Photosynthetic and Nitrogen-Fixing Proteins of Trichodesmium Both in Culture and In Situ from the North Atlantic

Marine cyanobacteria of the genus Trichodesmium occur throughout the oligotrophic tropical and subtropical oceans, where they can dominate the diazotrophic community in regions with high inputs of the trace metal iron (Fe). Iron is necessary for the functionality of enzymes involved in the processes of both photosynthesis and nitrogen fixation. We combined laboratory and field-based quantifications of the absolute concentrations of key enzymes involved in both photosynthesis and nitrogen fixation to determine how Trichodesmium allocates resources to these processes. We determined that protein level responses of Trichodesmium to iron-starvation involve down-regulation of the nitrogen fixation apparatus. In contrast, the photosynthetic apparatus is largely maintained, although re-arrangements do occur, including accumulation of the iron-stress-induced chlorophyll-binding protein IsiA. Data from natural populations of Trichodesmium spp. collected in the North Atlantic demonstrated a protein profile similar to iron-starved Trichodesmium in culture, suggestive of acclimation towards a minimal iron requirement even within an oceanic region receiving a high iron-flux. Estimates of cellular metabolic iron requirements are consistent with the availability of this trace metal playing a major role in restricting the biomass and activity of Trichodesmium throughout much of the subtropical ocean

Computational Methods for Pigmented Skin Lesion Classification in Images: Review and Future Trends

Skin cancer is considered as one of the most common types of cancer in several countries, and its incidence rate has increased in recent years. Melanoma cases have caused an increasing number of deaths worldwide, since this type of skin cancer is the most aggressive compared to other types. Computational methods have been developed to assist dermatologists in early diagnosis of skin cancer. An overview of the main and current computational methods that have been proposed for pattern analysis and pigmented skin lesion classification is addressed in this review. In addition, a discussion about the application of such methods, as well as future trends, is also provided. Several methods for feature extraction from both macroscopic and dermoscopic images and models for feature selection are introduced and discussed. Furthermore, classification algorithms and evaluation procedures are described, and performance results for lesion classification and pattern analysis are given