Relativistic quantum dynamics of scalar bosons under a full vector Coulomb interaction

The relativistic quantum dynamics of scalar bosons in the background of a full vector coupling (minimal plus nonminimal vector couplings) is explored in the context of the Duffin-Kemmer-Petiau formalism. The Coulomb phase shift is determined for a general mixing of couplings and it is shown that the space component of the nonminimal coupling is a {\it sine qua non} condition for the exact closed-form scattering amplitude. It follows that the Rutherford cross section vanishes in the absence of the time component of the minimal coupling. Bound-state solutions obtained from the poles of the partial scattering amplitude show that the time component of the minimal coupling plays an essential role. The bound-state solutions depend on the nonminimal coupling and the spectrum consists of particles or antiparticles depending on the sign of the time component of the minimal coupling without chance for pair production even in the presence of strong couplings. It is also shown that an accidental degeneracy appears for a particular mixing of couplings.Comment: 8 pages, 1 table. arXiv admin note: text overlap with arXiv:1403.603

Treatment of the Prominent Mandibular Angle by Using a Custom Made Surgical Splint

In this case report, we would like to present an alternative surgical technique for the treatment of the bilateral prominent mandibular angles by using a custom-made resin splint (template). The prefabricated template provided a precise outline for the osteotomy, which alleviated the uncertainty of the osseous cut. Furthermore, masseter muscle myomectomy was not necessary in this case which decreased morbidity, and procedure and recovery time, while assuring a more symmetric outcome

Judicial Restraints on Administrative Action: Effective or Illusory ?

As ações do projeto consistiram no reconhecimento da comunidade, realizando-se entrevistas, seguidas de um levantamento da demanda por espécies florestais e frutíferas, aquisição, transporte e distribuição das mudas e sementes. Das 28 propriedades cadastradas, 18 tornaram-se participantes, engajando-se no projeto. Na comunidade, a fruticultura é a principal atividade e o cupuaçu a principal cultura, presente em oito propriedades participantes com 2950 indivíduos plantados. Outras culturas importantes são: manga, pupunha, açaí, coco. O projeto promoveu também a introdução e o plantio de espécies vegetais com valor de mercado. Com as atividades do projeto, diversificaram-se as espécies florestais e frutíferas existentes na comunidade. Distribuíram-se 12.455 mudas de pau-rosa, cedro, andiroba, mogno, maçaranduba, seringueira, camu-camu (caçari), araçá-boi, cubiu e outras. Como perspectiva, as ações pretendem fixar o agricultor no campo, propor alternativas econômicas, sensibilizar a comunidade com relação à preservação da floresta e exploração racional dos recursos naturais.The activities of this project consisted in the recognition of the community by interviews, followed by a survey of the demand for forest and fruitful species, the acquisition, transport and distribution of seedlings and seeds. Of the 28 registered properties, 18 participated in the project. In the community, fruit culture is the main activity, and cupuaçu the main fruit in eight participant properties with 2950 plants. Other cultures are: mango, pupunha, açaí, coconut. The project also promoted the introduction and plantation of vegetal species with market value. Among the project activities, community forest and fruit species were diversified with 12,455 seedlings of wood-rose, cedar andiroba, mahogany, maçaranduba, seringueira, camu-camu, araçá-boi, cubiu and anothers were distributed. As the perspective, the activities intend to fix the agriculturist in the field, to consider economic alternatives, to make the community aware of the between preservation of the forest and the rational exploration of natural resources

Giant Mandibular Condyle Osteoma

Osteomas are benign tumors composed of mature compact or cancellous bone. They represent an uncommon lesion that occurs mainly in craniofacial complex bones. In jaws, they can appear on the bone surface as a polypoid or sessile mass, characterizing a peripheral osteoma (PO), or can be a lesion in the medullar space, then it is called central osteoma. In view of the scarcely reported cases about POs, this article presents a case of PO of the maxillofacial area that was surgically resected using hemicoronal approach

Histologic and Histomorphometric Analysis of Posterior Region of the Human Temporomandibular Disc

Objective The aim of this study was to analyze histologic and histomorphometric features of the articular disc in groups with and without disc displacement. Study design A sample of 39 temporomandibular joints TMJs (31 case specimens, 8 control specimens) from 28 patients (mean age 31.2 years) were recruited for this study. The patients were considered to be affected and treated surgically with disc repositioning when presenting painful clinical signs of disc displacement after unsuccessful nonsurgical treatment for at least 6 months. Of the control patients, 4 presented condyle fracture which required opening to be reduced for treatment, and 4 displayed active condyle hyperplasia. The posterior region of the disc was removed and sent for histologic and histomorphometric analysis. Histologic (hematoxylin-eosin) and histomorphometric (picro-Sirius red) analyses were performed. Statistically significant differences between the analyzed groups were accessed through the chi-squared test (P ≤ .05). The Mann-Whitney U test was used to observe the differences between mean values when variables did not present normal distribution [Kolmogorov-Smirnov(a) test]. Results There were no significant differences between the groups in relation to the parameters studied by histologic and histomorphometric analysis (using or not using polarization). Conclusions To the limits of this study, there were no significant histologic and histomorphometric differences in the articular disc between groups with and without TMJ dysfunction

O RISCO CAMBIAL NA OTIMIZAÇÃO DE CARTEIRAS INTERNACIONAIS: O EFEITO DOS PAÍSES LATINO-AMERICANOS

Este trabajo analisa la existencia de beneficios (riesgo y retorno) en la inclusión de mercados emergentes globales y, en especial, de los países de latinoamérica en la formación de carteras internacionales óptimas considerando el riesgo cambial. Para esto, el estudio se basea en el análisis de tasas de retornos mensales, desviación estándar y coeficientes de correlación en terminos de moneda local, dólar, yen, marco alemán y euro, de los Índices de los Mercados de Acciones (IMAs) de diecinueve países, de los Índices de Bolsa de Valores de São Paulo, Buenos Aires, México, Santiago y de Caracas, para el período compreendido entre enero de 1994 y diciembre de 2000. Los resultados indican que todavía existen evidencias de los benefícios de la diversificación internacional en terminos de desempeño para los inversionistas. Cabe indicar, también, que la inclusíon del componente de latinoamérica en las distintas carteras otimizadas, casi no acrecienta benefício algún al desempeño general de estas carteras, siendo nulo para las carteras del invertidor japonés.Este trabalho analisa a existência de benefícios (risco e retorno) na inclusão de mercados emergentes globais e, em especial, dos países latino-americanos na formação de carteiras internacionais ótimas considerando o risco cambial. Para isto, o estudo baseia-se na análise das taxas de retornos mensais, desvio-padrão e coeficientes de correlação em termos de moeda local, dólar, iene, marco alemão e euro, dos Índices dos Mercados de Ações (IMAs) de dezenove países, dos Índices de Bolsa de Valores de São Paulo, Buenos Aires, México, Santiago e de Caracas, para o período compreendido entre janeiro de 1994 e dezembro de 2000. Os resultados indicam que ainda existem evidências dos benefícios da diversificação internacional em termos de desempenho para os investidores. Cabe indicar, também, que a inclusão do componente latino-americano nas diferentes carteiras otimizadas, quase não acrescenta benefício algum ao desempenho geral destas carteiras, sendo nulo para as carteiras do investidor japonês

Progresso científico e incomensurabilidade em Thomas Kuhn

Despite many criticisms received along his academic career, Thomas Kuhn has undoubtedly advanced a new image about scientific progress. He showed that progress occurs in two different, but complementary directions. His thesis was that scientific development occurs through the essential tension between what is normal and what is revolutionary in science. According to Kuhn, there is progress in the sense of profounding of knowledge, given by the acquisition of a paradigm, and there is progress by means of the enlargement of knowledge accomplished by the emergence of incommensurability. The main point developed in this article states that Kuhn's problem was to think incommensurability and paradigms as concepts which have only linguistic and theoretical meanings.Apesar das inúmeras críticas que recebeu ao longo de sua produção acadêmica, Thomas Kuhn produziu, inegavelmente, uma nova imagem acerca do progresso científico. A rigor, ele mostrou que o progresso ocorre em duas direções diferentes e complementares. Isso o levou a advogar a tese de que o desenvolvimento da ciência se dá por intermédio de uma tensão essencial entre o normal e o revolucionário. Segundo Kuhn, há o progresso no sentido de aprofundamento do conhecimento - proporcionado pela aquisição de um paradigma - e há o progresso no sentido de ampliação do conhecimento - gerado pela emergência da incomensurabilidade. O argumento central que desenvolvemos, neste artigo, afirma que o problema de Kuhn foi ter começado, com o passar do tempo, a pensar esses dois conceitos fundamentais (paradigma e incomensurabilidade) somente em suas conotações lingüísticas e teóricas

Acute effects of mechanical ventilation with hyperoxia on the morphometry of the rat diaphragm

BACKGROUND: Prolonged mechanical ventilatory support (MVS) combined with high oxygen concentrations has a negative impact on diaphragm function. However, the acute effects of MVS with hyperoxia have not been elucidated. Objective: To analyze the acute effects of mechanical ventilation with hyperoxia on the morphometry of the rat diaphragm. METHODS: An experimental, prospective study was conducted with Wistar rats (weight: 400±20 g), which were randomly allocated to two groups. The control group (n=4) was anesthetized, tracheostomized and kept spontaneously breathing room air for 90 minutes. The experimental group (n=5) was also anesthetized, curarized, tracheostomized and kept in controlled mechanical ventilation for the same amount of time. Both groups were submitted to median thoracotomy for sample collection of costal fibers from the diaphragm muscle, which were sectioned every 5 μm and stained with hematoxylin and eosin for the morphometric study. Independent Student's t tests were employed to investigate differences between groups, with a significance level of p<0.05. RESULTS: There were no signs of acute muscle lesions, however the blood capillaries became dilated in the experimental group. The mean morphometric data related to the maximum cross-sectional diameter of the diaphragm costal fibers were 61.78 ±17.79 µm and 70.75±9.93 µm (p=0.045) for the control and experimental groups, respectively. CONCLUSIONS: Short-term mechanical ventilation with hyperoxia led to significant microvascular and muscle changes, which may reflect the onset of an inflammatory process.CONTEXTUALIZAÇÃO: A asssistência ventilória mecânica (AVM) prolongada associada a altas frações de oxigênio produz impacto negativo na função diafragmática. No entanto, não são claros os efeitos agudos da AVM associada a altas frações de oxigênio em pulmões aparentemente sadios. OBJETIVO: Analisar os efeitos agudos da ventilação mecânica com hiperóxia na morfometria do diafragma de ratos. Métodos: Estudo experimental prospectivo, com nove ratos Wistar, com peso de 400±20 g, randomizados em dois grupos: controle (n=4), anestesiados, traqueostomizados e mantidos em respiração espontânea em ar ambiente por 90 minutos e experimental (n=5), também anestesiados, curarizados, traqueostomizados e mantidos em ventilação mecânica controlada pelo mesmo tempo. Foram submetidos à toracotomia mediana para coleta da amostra das fibras costais do diafragma que foram seccionadas a cada 5 μm e coradas pela hematoxilina e eosina para o estudo morfométrico. Para a análise estatística, foi utilizado o teste t de Student não pareado, com nível de significância de p<0,05. RESULTADOS: Não foram encontrados sinais indicativos de lesão muscular aguda, porém observou-se dilatação dos capilares sanguíneos no grupo experimental. Os dados morfométricos do diâmetro transverso máximo da fibra muscular costal foram em média de 61,78±17,79 µm e de 70,75±9,93 µm (p=0,045) nos grupos controle e experimental respectivamente. CONCLUSÃO: A ventilação mecânica de curta duração com elevada concentração de O2 produziu marcantes alterações microvasculares e musculares, podendo refletir o início do processo inflamatório.Universidade Federal de UberlândiaUniversidade Federal de São Paulo (UNIFESP) Departamento de HistologiaUNIFESP Departamento de AnatomiaUniversidade Federal do Triângulo MineiroUNIFESP, Depto. de HistologiaUNIFESP, Depto. de AnatomiaSciEL