Resumo -O objetivo deste trabalho foi avaliar variáveis discriminantes no mapeamento digital de solos com uso de redes neurais artificiais. Os atributos topográficos elevação, declividade, aspecto, plano de curvatura e índice topográfico, derivados de um modelo digital de elevação, e os índices de minerais de argila, óxido de ferro e vegetação por diferença normalizada, derivados de uma imagem do Landsat7, foram combinados e avaliados quanto à capacidade de discriminação dos solos de uma área no noroeste do Estado do Rio de Janeiro. Foram utilizados o simulador de redes neurais Java e o algoritmo de aprendizado "backpropagation". Os mapas gerados por cada um dos seis conjuntos de variáveis testados foram comparados com pontos de referência, para a determinação da exatidão das classificações. Esta comparação mostrou que o mapa produzido com a utilização de todas as variáveis obteve um desempenho superior (73,81% de concordância) ao de mapas produzidos pelos demais conjuntos de variáveis. Possíveis fontes de erro na utilização dessa abordagem estão relacionadas, principalmente, à grande heterogeneidade litológica da área, que dificultou o estabelecimento de um modelo de correlação ambiental mais realista. A abordagem utilizada pode contribuir para tornar o levantamento de solos no Brasil mais rápido e menos subjetivo.Termos para indexação: atributos do terreno, classificação de solos, modelo digital de elevação, redes neurais artificiais. Topographic attributes and Landsat7 data in the digital soil mapping using neural networksAbstract -The objective of this study was to evaluate discriminant variables in digital soil mapping using artificial neural networks. The topographic attributes elevation, slope, aspect, plan curvature and topographic index, derived from a digital elevation model, and the indexes of clay minerals, iron oxide and normalized difference vegetation, derived from a Landsat7 image, were combined and evaluated for their ability to discriminate soils of an area at the northwest of Rio de Janeiro State. The Java neural simulator and the backpropagation learning algorithm were used. The maps generated by each of the six tested sets of variables were compared with reference points for determining the rating accuracy. This comparison showed that the map produced with the use of all the variables reached a performance (73.81% of agreement) superior to maps produced by other sets of variables. Possible sources of error in the use of this approach are mainly related to the great lithological heterogeneity of the area, which hindered the establishment of a more realistic model of environmental correlation. The approach can help make the soil survey in Brazil faster and less subjective.
IntroduçãoO advento da seringa de injeção hipodérmica em 1853 (Charles Gabriel Pravaz), logo seguida da fabricação da seringa inteiramente de vidro em 1869 (Georg Wilhelm Amathus Luer), permitiu a administração de medicamentos via parenteral. O novo processo fez sucesso, mas, imediatamente, surgiram as complicações. ARTIGO DE REVISÃO ResumoAnálise de 32 casos de acidentes por injeção, na maioria das vezes, de substâncias oleosas no músculo deltoide. Os acidentes caracterizaram-se por dor e reações tróficas locais. Em muitos casos, simultaneamente, ocorreram distúrbios isquêmicos nas regiões escapular, peitoral e, especialmente, na extremidade do membro. Presume-se que esse complexo lesional é gerado: 1) pela ação lesiva do medicamento nas terminações nervosas, nos tecidos moles e perivasais; e/ou 2) pela entrada fortuita da substância no interior dos vasos, produzindo embolia e/ou endotelite trombosante; e/ou 3) pelo despertar de fenômenos vasomotores.As lesões da mão, geralmente, foram mais graves que as lesões deltoidianas, com a eventual perda de dedos, espontânea ou cirúrgica. Os diversos quadros clínicos do acidente foram semelhantes, mas algumas características lesionais permitiram identificar mecanismos fisiopatogênicos peculiares, o que tem significado conceitual e terapêutico. Palavras-chave:Dermite livedoide, arterite cútis medicamentosa, embolia cútis medicamentosa, síndrome de Nicolau, síndrome de Freudenthal, acidente por injeção intramuscular, gangrena de mão. AbstractAnalysis of 32 cases of accidental injection of oily suspension (in most cases) into the deltoid muscle is reported. Pain and local ulcers characterized the accidents. In many cases, simultaneous ischemic disorders were observed in the scapular and pectoral regions and especially in the end of the upper limb. It is presumed that this complex lesion was caused by 1) the harmful action of the medication on nervous terminations, soft and perivascular tissues; and/or 2) occasional entrance of the substance into blood vessels, causing embolism and/or thrombotic endothelitis; and/or 3) vasomotor phenomena.Hand injuries were generally more severe than injuries in the deltoid region, with occasional spontaneous or surgical loss of fingers. Clinical statuses were similar, though some lesions had features, which allowed identification of peculiar physiopathogenic mechanisms, with conceptual and therapeutic significance.
The obturator artery is a branch of the internal iliac artery, although there are reports documenting variations, with origin from neighboring vessels such as the common iliac and external iliac arteries or from any branch of the internal iliac artery. It normally runs anteroinferiorly along the lateral wall of the pelvis to the upper part of the obturator foramen where it exits the pelvis by passing through said foramen. Along its course, the artery is accompanied by the obturator nerve and one obturator vein. It supplies the muscles of the medial compartment of the thigh and anastomoses with branches of the femoral artery on the hip joint. We report a rare arterial variation in a Brazilian cadaver in which the obturator artery arose from the external iliac artery, passing beyond the external iliac vein toward the obturator foramen, and was accompanied by two obturator veins with distinct paths. We also discuss its clinical significance.
RESUMOO manejo inadequado e a baixa disponibilidade de nutrientes nos solos da Zona da Mata de Minas Gerais, têm resultado em baixas produtividades de pastagens, aparecimento de solos descobertos e perdas de solo por erosão. O objetivo deste trabalho foi avaliar a capacidade das imagens do sensor ASTER em identificar diferentes níveis de degradação de pastagens. A área de estudo inclui parte dos municípios de Viçosa, Teixeiras e São Miguel do Anta, perfazendo cerca de 3.314 ha. Devido às características das pastagens da região, foram utilizados quatro níveis de degradação: leve, moderada, forte e muito forte. A classe que apresentou maior erro de classificação foi a pastagem com nível de degradação muito forte (Pastagem 4), com 53,91% dos pixels classificados, confundindo-se com as demais classes. A pastagem com nível de degradação moderada (Pastagem 2) apresentou a melhor classificação. Da área avaliada, aproximadamente 70% correspondem a pastagens, sendo 56,46% classificadas como fortemente degradadas; 28,73% Mata/Capoeira e 1,54% plantações de café. Os resultados permitiram concluir que as imagens do sensor ASTER apresentaram um potencial satisfatório para separar os diferentes níveis de degradação de pastagens. Palavras-chave: pastagens degradadas, sensoriamento remoto, classificaçãoUse of ASTER sensor images for the identification of levels of pasture degradation ABSTRACTThe improper management and the low availability of nutrients of soils in "Zona da Mata" in Minas Gerais State, Brazil, have led to low productivity of natural pasture, emergence of bare soils and soil losses by erosion. The objective of this work was to evaluate the capacity of ASTER sensor images to identify different levels of degradation in pasture lands. The studied area includes part of Viçosa, Teixeiras, and São Miguel do Anta municipalities, forming a total area around 3,314 ha. Due to natural characteristics of the pasture in this region, four levels of degradation were used: light, moderate, strong, and very strong. The class that showed the highest error in the classification was the very strong, degraded with 53.91% of the classified pixels, not distinguishable from the other classes. The moderate degradation class showed the best classification. From the total evaluated area, approximately 70% corresponded to pasture, 56.46% of which was classified in the strong degradation level, 28.73% to 'Mata/Capoeira' and only 1.54% to coffee plantations.The results permit to conclude that the use of sensor ASTER images was satisfactory to separate degradation levels of pasture lands in the studied area.
Objective: to report the prevalence of arterial corona mortis and to describe its surgical and clinical applicabilities. Methods: We dissected 60 hemipelvises (50 men and 10 women) fixed in a 10% formalin solution for the purpose of gathering information on corona mortis. We measured the caliber and length of the obturator artery and its anastomotic branch with the aid of a digital caliper and submitted the data to statistical analyzes and comparisons with the GraphPad Prism 6 software. Results: arterial corona mortis was present in 45% of the studied sample. The most common origin of the obturator artery was the internal iliac artery; however, there was one exceptional case in which it originated from the femoral artery. The caliber of the anastomotic branch was on average 2.7mm, whereas the caliber of the obturator artery was 2.6mm. Conclusion: the vascular connections between the obturator, internal iliac, external iliac and inferior epigastric arterial systems are relatively common over the upper pubic branch. The diameter and a trajectory of the anastomotic artery may vary. Thus, iatrogenic lesions and pelvic and acetabular fractures can result in severe bleeding that puts the patient’s life at risk.
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