Avaliação histométrica das áreas de tração e compressão do periodonto dos primeiros molares de ratos submetidos à movimentação dentária induzida

Pós-graduação em Odontologia - FOA

Atenuação de múltiplas e compressão do pulso fonte em dados de sísmica de reflexão utilizando o filtro Kalman-Bucy

O objetivo central deste trabalho é o estudo e a aplicação do método Kalman-Bucy no processo de deconvolução ao impulso e de deconvolução com predição, onde é considerado que os dados observados são classificados como não-estacionários. Os dados utilizados neste trabalho são sintéticos e, com isto, esta Tese tem características de um exercício numérico e investigativo. O operador de deconvolução ao impulso é obtido a partir da teoria de CRUMP (1974) fazendo uso das soluções das equações Wiener-Hopf apresentadas por KALMAN-BUCY (1961) nas formas contínuas e discretas considerando o processo como não estacionário. O operador de predição (KBCP) está baseado nas teorias de CRUMP (1974) e MENDEL ET AL (1979). Sua estrutura assemelha-se ao filtro Wiener-Hopf onde os coeficientes do operador (WHLP) são obtidos através da autocorrelação, e no caso (KBCP) são obtidos a partir da função b_i(k). o problema é definido em duas etapas: a primeira consta da geração do sinal, e a segunda da sua avaliação. A deconvolução realizada aqui é classificada como estatística, e é um modelo fortemente baseado nas propriedades do sinal registrado e de sua representação. Os métodos foram aplicados apenas em dados sintéticos de seção fonte-comum obtida a partir dos modelos com interfaces contínuas e camadas homogêneas.

Avaliação da influência da incorporação de substâncias desinfetantes na resistência à compressão e à tração diametral de dois gessos tipo IV

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência do método de aquecimento de revestimentos fosfatados sobre sua resistência à compressão e sobre a rugosidade de superfície e estabilidade dimensional de ligas de Ni-Cr e Ni-Cr-Ti

Pós-graduação em Odontologia - FOA

Análise estatística do comportamento mecânico à compressão do compósito cimento-madeira

Este trabalho objetiva contribuir para a aplicação do resíduo do tecido lenhoso de espécies vegetais tropicais, na forma de serragem, proveniente da indústria madeireira do estado do Pará, da região metropolitana de Belém em particular, para a fabricação de compósito madeira-cimento. Devido à natural incompatibilidade química entre a madeira e o cimento, este procedimento resulta em um retardamento de pega, de intensidade dependente da espécie vegetal utilizada. Este efeito pode ser combatido com diversos processos, como por exemplo, a aditivação da mistura com aceleradores de pega, a mineralização da madeira, a carbonatação acelerada, dentre outros. As análises foram feitas a partir da resistência à compressão aos 28 dias para argamassas produzidas com teores de madeira de 2, 3,5 e 5% em massa, com cimento CP I e CP II, e ainda com e sem o uso de aditivo acelerador de pega a base de cloreto de cálcio. Assim sendo, os resultados obtidos foram analisados estatisticamente para que a influência do teor de madeira e da aditivação à base de cloreto de cálcio na resistência à compressão fosse avaliada. A maioria dos trabalhos existentes utiliza espécies de clima temperado, e de reflorestamento, pouco tendo sido avaliado para espécies de clima tropical. Neste sentido, o presente trabalho representa um esforço pioneiro no desenvolvimento de compósitos madeira-cimento para os materiais e resíduos disponíveis na região Amazônica.

A Catuama e o bilobalide na regeneração nervosa periférica de ratos submetidos à secção do nervo isquiático

The Catuama((R)) is composed of four Brazilian plants extracts (Paullinia cupana, Trichilia catigua, Ptychopetalum olacoides e Zingiber officinale). The Catuama((R)) is known as having neuroprotector, anti-inflammatory, antioxidant and antidepressant effects. Bilobalide, extracted from leaves of Ginkgo biloba, is known by its neuroprotective effect in the central and peripheral nervous systems. The present study evaluates the effect of Catuama((R)) and bilobalide on peripheral nerve regeneration in rats following a sciatic nerve section. Sciatic nerve of forty adult rats was transected with a 10-mm gap and the proximal and distal nerve stumps were fixed in a silicone tube filled with liquid collagen. The animals were divided into four groups: the control group (A), two groups treated with Catuama((R)) by gavage along 28 days after the surgery in different doses of 100 (B) and 400mg. kg(-1) (C) and the group using 200 mu M bilobalide (D) associated with the liquid collagen in the silicone tube. Evaluations were done by a walk test on the first, fifth and tenth week after the surgery. Electrophysiological stimulation and quantitative and qualitative histological analyses of the sciatic nerve and gastrocnemius muscle were also performed on the tenth week after the surgery. All groups showed good regeneration but no statistical difference was found between treatments and control groups (P > 0.05).

Estudo da dureza e da resistência à compressão de resinas compostas para dentes posteriores após a imersão em água destilada. Efeito da aplicação de selante superficial

Novos compósitos têm surgido no mercado especificamente destinados à confecção de restaurações estéticas posteriores. Entretanto, embora tais materiais apresentem resultados iniciais animadores, há a necessidade de comprovações adicionais para que possam ser utilizados com segurança. Resinas compostas posteriores são submetidas a estresses complexos de compressão e abrasão durante a mastigação e a aplicação de selantes superficiais tem sido relatada como forma de aumentar a resistência ao desgaste destes materiais. O presente trabalho teve como propósito avaliar a dureza e a resistência à compressão das resinas compostas Alert (Jeneric/Pentron), Ariston (Vivadent), Definite (Degussa), P60 (3M), Solitarie (Kulzer), Surefil (Dentsply) e Z100 (3M) após 90 dias de imersão em água destilada, recobertas com selante Protect It (Jeneric/Pentron) e submetidas à ciclagem mecânica (10.000 ciclos, 600N, 5Hz). Os ensaios de dureza (n=8) foram realizados em aparelho Wolpert, com diamante Vickers e peso de 50gf aplicado por 30 segundos, antes e após períodos de imersão de 30, 60 e 90 dias. Os ensaios de resistência à compressão (n=8) foram realizados somente após 90 dias, em corpos-de-prova cilíndricos medindo 8mm de altura por 4mm de diâmetro. Apenas os espécimes destinados à compressão foram ciclados mecanicamente. Os ensaios foram realizados em máquina MTS 810, equipada com célula de carga de 10kN (ciclagem) e 100kN (compressão) e velocidade de 0,5mm/min. Após análise de variância (p<0,05), os resultados mostraram, previamente à imersão, maiores valores de dureza para os materiais Z100 (74,253VHN) e Ariston (71,308VHN). A seguir, com valor semelhante à resina Ariston, mas inferior à resina Z100, apresentou-se o material Surefil (69,969VHN)...(Resumo completo, clicar acesso eletrônico abaixo)

Antidepressants for anorexia nervosa

Background Anorexia Nervosa ( AN) is an illness characterised by extreme concern about body weight and shape, severe self-imposed weight loss, and endocrine dysfunction. In spite of its high mortality, morbidity and chronicity, there are few intervention studies on the subject.Objectives The aim of this review was to evaluate the efficacy and acceptability of antidepressant drugs in the treatment of acute AN.Search strategy The strategy comprised of database searches of the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register, MEDLINE (1966 to April 28th, 2005), EMBASE (1980 to week 36, 2004), PsycINFO (1969 to August week 5, 2004), handsearching the International Journal of Eating Disorders and searching the reference lists of all papers selected. Personal letters were sent to researchers in the field requesting information on unpublished or in-progress trials.Selection criteria All randomised controlled trials of antidepressant treatment for AN patients, as de fined by the Diagnostic and Statistical Manual, fourth edition (DSM-IV) or similar international criteria, were selected.Data collection and analysis Quality ratings were made giving consideration to the strong relationship between allocation concealment and potential for bias in the results; studies meeting criteria A and B were included. Trials were excluded if non-completion rates were above 50%. The standardised mean difference and relative risk were used for continuous data and dichotomous data comparisons, respectively. Whenever possible, analyses were performed according to intention- to-treat principles. Heterogeneity was tested with the I-squared statistic. Weight change was the primary outcome. Secondary outcomes were severity of eating disorder, depression and anxiety symptoms, and global clinical state. Acceptability of treatment was evaluated by considering non-completion rates.Main results Only seven studies were included. Major methodological limitations such as small trial size and large confidence intervals decreased the power of the studies to detect differences between treatments, and meta-analysis of data was not possible for the majority of outcomes. Four placebo-controlled trials did not find evidence that antidepressants improved weight gain, eating disorder or associated psychopathology. Isolated findings, favouring amineptine and nortriptyline, emerged from the antidepressant versus antidepressant comparisons, but cannot be conceived as evidence of efficacy of a specific drug or class of antidepressant in light of the findings from the placebo comparisons. Non-completion rates were similar between the compared groups.Authors' conclusions A lack of quality information precludes us from drawing de finite conclusions or recommendations on the use of antidepressants in acute AN. Future studies testing safer and more tolerable antidepressants in larger, well designed trials are needed to provide guidance for clinical practice.

Análise das resistências de embutimento e de compressão para madeiras de pinus e eucalipto

The connections in the wood structures are the places with high concentrations of stresses and therefore are more fragile than the rest of the structure. The connections between pieces of wood can be made by metal pins (nails or screws). The compression and embedment strength has significant influence on the calculation of the connections. The main aim of this work was to evaluate the compression and embedment strength in the directions parallel, inclined at 45° and normal to the grain, using standard specimens according to ABNT NBR 7190/1997 standard. The compression and embedment strength were initially evaluated according to ABNT NBR 7190/1997, which admits the deformation of 2‰ as limit of embedment and the ratio between the ultimate strength and the area of application of load in the specimen for the compressive strength. Afterward, the embedment strength was evaluated by the EUROCEDE 5 /1995 European standard, which use the limit of 5 mm of the displacement for the embedment. Specimens of Pinus oocarpa, Cumaru and Pinus taeda were used in tests to calibration of equipment and specimens of Pinus taeda and Eucalipto citriodora were used to compare the results of strength. The results of strength were evaluated based on statistical analysis. The results of compressive strength for the Pinus taeda showed no significant differences in embedment strength in the directions parallel and normal to the grain. For the Eucalipto citriodora only in the direction parallel to grain the compression strength was not significant compared with the embedment strength. For both species, only the parallel compression strength and inclined at 45o to the grain, which were to the grain, which were admitted the strain of 2‰ were not significantly different compared with the compression strength determined according to ABNT NBR 7190/1997. The normal compression strength obtained according to ABNT NBR 7190/1997 and ultimate compression strength not ...

O padrão de compressão de video MPEG moving picture experts group

This work focuses on the study of video compression standard MPEG. To this end, a study was undertaken starting from the basics of digital video, addressing the components necessary for the understanding of the tools used by the video coding standard MPEG. The Motion Picture Experts Group (MPEG) was formed in the late '80s by a group of experts in order to create international standards for encoding and decoding audio and video. This paper will discuss the techniques present in the video compression standard MPEG, as well as its evolution. Will be described in the MPEG-1, MPEG-2, MPEG-4 and H.264 (MPEG-4 Part 10), however, the last two will be presented with more emphasis, because the standards are present in most modern video technologies, as in HDTV broadcasts

Síndromes paraneoplásicas hematológicas em cães

Tumoral masses can cause several direct problems in the organism, such as invading organs and altering their functions, leading to other problems such as the Paraneoplastic syndrome. The paraneoplastic syndrome is an alteration in the structure and function of the body due to the non-invasive actions of the tumor, for example, liberating hormones, peptides, cytokines and leading to cross reactions between normal tissues. The syndrome can affect different locations in the body, being that some are indicative of specific tumors, however the interpretation of the clinical and pathological findings referring to this syndrome should be utilized in the diagnostic and treatment. In the hematological paraneoplastic syndrome, there are alterations that occur due to indirect actions of the tumor on the blood cellular elements and the coagulation system, and that are generally detected in routine clinical and laboratorial exams. This study objective is to aboard some hematological paraneoplastic syndromes in dogs such as: anemia, thrombocytopenia, neutrophilic leukocytosis, hypergammaglobulinemia and erythrocytosis, emphasizing the different etiologies that may assist in differential diagnosis and the principal neoplasm related to this syndrome. Besides this, the early discovery and treatment of the paraneoplatic syndrome is important as the tumor itself, as it improves the prognostic and quality of life of the patient

Síndromes Paraneoplásicas em Pequenos Animais

Paraneoplastic syndromes are being increasingly recognized in dogs and cats in veterinary medicine as they often are oncological emergencies and may help in early diagnosis of primary neoplasm, performing a more effective treatment, which usually is the removal of the tumor, and thereby improving the quality of life of the animal and perhaps prognosis. The syndrome is caused by the tumor through the production of substances such as hormones and cytokines that are released into circulation and are responsible for the appearance of distant signals from the primary neoplasm. These syndromes can involve multiple systems of the body, among them we mention: the hematology, the dermatologist, the neurologist, endocrine and musculoskeletal

Comparação dos efeitos de compressão isostática e compressão uniaxial na obtenção da liga NiTi por metalurgia do pó

Several alloys present the shape memory effect and among them, the equiatomic NiTi alloy, nitinol, is the most important one. It is usually used in several engineering applications and also in biomedical devices, in the fabrication of orthodontic wire, stents and Judet staples. Although a considerable amount of these biomedical devices is utilized in Brazil and a fraction of it is already made here, all nitinol used is bought abroad. Thus, it is important to develop the necessary know-how to fabricate NiTi wire and sheet. It would mean less importation with job creation and wealth generation for the country. In this work nitinol was obtained powder metallurgy from elemental powders of Ti and Ni using uniaxial compression and uniaxial compression followed by isostatic compression. The final densities achieved were determined by the Archimedes method. The precipitation of intermetallic secondary phases was studied and the samples were characterized by metallographic analysis, optical microscopy and X-ray diffraction. Results indicated that 50 hours sintering route showed a low amount of intermetallics, and no trace of unreacted powder. XRD and metallography at room temperature indicated B19’ as the predominant phase, which corresponds to martensite. Although density results showed little dispersion, the most dense sample was compacted under uniaxial compression and presented 4.8 g/cm3, corresponding to 20.84% porosity. Density variation was considered normal to the measurement process and independent of the compaction mode

Estudo mecânico comparativo da estabilização de fratura ilíaca com dois tipos de implantes (parafusos com placa de compressão dinâmica e parafusos associados ao polimetilmetacrilato) em hemipelves caninas sintéticas

Pós-graduação em Cirurgia Veterinária - FCAV

Diretrizes de conduta e tratamento de síndromes febris periódicas associadas à criopirina (Criopirinopatias–CAPS)

To establish guidelines based on cientific evidences for the management of cryopyrin associated periodic syndromes. The Guideline was prepared from 4 clinical questions that were structured through Pico (Patient, Intervention or indicator, Comparison and Outcome), to search in key primary scientific information databases. After defining the potential studies to support the recommendations, these were graduated considering their strength of evidence and grade of recommendation. 1215 articles were retrieved and evaluated by title and abstract; from these, 42 articles were selected to support the recommendations. 1. The diagnosis of Caps is based on clinical history and clinical manifestations, and later confirmed by genetic study. Caps may manifest itself in three phenotypes: FCAS (mild form), MWS (intermediate form) and Cinca (severe form). Neurological, ophthalmic, otorhinolaryngological and radiological assessments may be highly valuable in distinguishing between syndromes; 2. The genetic diagnosis with NLRP3 gene analysis must be conducted in suspected cases of Caps, i.e., individuals presenting before 20 years of age, recurrent episodes of inflammation expressed by a mild fever and urticaria; 3. Laboratory abnormalities include leukocytosis and elevated serum levels of inflammatory proteins; 4. Targeted therapies directed against interleukin-1 lead to rapid remission of symptoms in most patients. However, there are important limitations on the long-term safety. None of the three anti-IL-1β inhibitors prevents progression of bone lesions.