356 resultados para Toit vert


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Nowadays, composite resins are the direct restorative materials more important in dental clinical performance, due to their versatility and aesthetic excellence. Bis-GMA (2,2-bis[4(2-hydroxy-3-metacryloxypropoxy)phenil]propane) is the base monomer more frequently used in restorative composite resins. However, this monomer presents some disadvantages, such as high viscosity and two aromatic rings in its structure that can promote allergic reactions to the humans. In this work, the main purpose was to synthesize new monomers from glycidyl methacrylate to use in dental restorative materials. Structural characterization of the monomers was carried out through FTIR and NMR 1H, and eight composites were produced from the new monomers, by addition of silane-treated alumino silicate particles (inorganic filler) and a photocuring system (camphorquinone and ethyl 4-dimethylaminebenzoate). The composites were analyzed by environmental scanning electronic microscopy and the water sorption and solubility, compressive strength and elastic modulus were determined. A commercial composite resin [Z100 (3M)] was used to comparison effect. The new composites presented general characteristics similar to the commercial ones; however, they didn t present the properties expected. This behavior was attributed to the lower degree of monomer reaction and to the granulometry and size distribution of the mineral filler in the polymeric matrix

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The people of Ceará state are descended from miscegenation between the Portuguese colonizers and the native population, resulting in a different facial pattern from other populations. It is important that this pattern be thoroughly understood, along with its minimum and maximum values so that they can be assessed and respected, allowing professionals who deal with the craniofacial complex to work more efficiently and scientifically. Aim: To characterize the morphological pattern of individuals from Ceará state, whose father and grandfather are also native from Ceará, in the 10-12 year age group, not submitted to previous orthodontic treatment, in order to determine: 1) the prevalence of occlusal pattern; 2) the prevalence of dental anomalies (DA) and, 3) the skeletal and dental cephalometric characteristics of individuals that present with normal occlusion and harmonious facial pattern. Methodology: A list of 10-12 year-olds was obtained from 515 schools containing 162,713 students (Education Secretariat of Ceará State), from which 234 individuals were examined (107 boys and 157 girls). The assessment criteria adopted were: 1) Angle s Classification System to determine occlusal pattern. The occlusal characteristics were measured through overbite, overjet, crowding and interincisal diastema. 2) DA are anomalies of number, shape, size, eruption and structure and, 3) in the group that presented with normal occlusion, we used cephalometric analysis measures proposed by Downs, Steiner, Tweed, Holdaway, Jacobson and McNamara. Results: 1) 25.8% of the schoolchildren had normal occlusion, 47.5% class I malocclusion, 22.3% class II malocclusion and 4.2% class III malocclusion. No statistically significant difference was found between the age group studied and sex. Thirty percent of the individuals had normal overbite, while 36.7% and 19.7% had increased and reduced overbite, respectively. Normal overjet was found in 33.7% of the individuals, increased overjet in 50% and reduced in 16.3%. Dental crowding was observed in 62.5% of the individuals and the presence of interincisal diastema in 14.8%. 2) The prevalence of DA was 56.1%, 6.8% in the number, 10.8% in shape, 4.1% in size, 34.5% in eruption, 26.4% in structure and 17.4% had more than one DA. No association was found between DA and sex, but DA was significantly associated to malocclusion (p<0.05); 3) there was no association between sex or facial type between the measures of nasal-labial angle, position and effective maxillary length, effective mandibular length and the sagittal relationship between the molars, overjet and overbite, position of upper incisors, lower incisors and between the incisors themselves. There was a difference between sex, on the VERT index and in lower anterior facial height, upper incisor inclination and line-H, between facial types for the occlusal plane angles, mandibular plane, facial axis, lower incisor inclination, mandibular position, upper incisor position, lower anterior facial height, ANB and line-H. It was concluded that: 1) the most prevalent occlusal type was class I malocclusion, with no distinction for sex or age group, and the assessment of occlusal characteristics showed that excessive overbite and overjet were the most predominant findings, along with a high occurrence of tooth crowding; 2) a high prevalence of DA was found, particularly eruption anomalies, not influenced by sex but significantly associated to malocclusion and 3) individuals from Ceará are predominantly brachyfacial, exhibiting a number of similarities inherent to their facial pattern, such as a convex profile, retracted jaw, reduced lower third and protruded lower incisors. This study was multidisciplinary, involving researchers from the areas of epidemiology, radiology and dentistry, thereby meeting the multidisciplinarity requirements of the Postgraduate Program in Health Sciences

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Realiza estudos de caracterização química, físico-química e de pré-formulação de Arrabidaea chica (Humb. & Bonpl.) B. Vert., pertencente à família Bignoniaceae, a qual recebe várias denominações, sendo que na região amazônica ela é conhecida popularmente como pariri, amplamente utilizada na medicina popular para o tratamento de várias doenças, dentre elas as enfermidades da pele causadas por dermatomicoses. A utilização de produtos naturais de origem vegetal implica no controle de qualidade farmacobotânico e em ensaios de pureza que compõem as especificações técnicas da espécie. Para isso, foi realizada a descrição anatômica das folhas jovens e maduras da planta a partir de observações realizadas ao microscópio óptico em cortes histológicos. Os testes Farmacopéicos incluíram a determinação da distribuição granulométrica do pó da planta, determinação do teor de umidade e de cinzas totais, e para a tintura foram realizadas determinações de pH, densidade aparente e teor de sólidos, sendo realizadas ainda a prospecção química, o perfil cromatográfico por CCO e CLAE, além da avaliação da sua atividade antimicrobiana. Tanto para o pó quanto para a tintura de A.chica foram observados os perfis por espectroscopia na região do infravermelho e perfis térmicos por TG e OTA. Foram realizados ainda, os estudos de pré-formulação através de espectroscopia na região de infravermelho e análise térmica (TG e OT A) das misturas físicas dos adjuvantes da formulação proposta para veicular a solução extrativa, com a finalidade de avaliar possíveis incompatibilidades da solução extrativa com os mesmos. Os resultados obtidos evidenciaram que a tintura de A. chica se adequa ao fim pretendido, além de ter assegurado a compatibilidade com os adjuvantes testados para constituírem a formulação proposta, já que não foi observado indícios de incompatibilidade física ou química entre os mesmos. Os estudos forneceram dados relevantes para o desenvolvimento da formulação proposta, visando obter resultados rápidos e com a precisão desejada.

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Os solventes orgânicos são substâncias neurotóxicas que podem causar efeitos danosos sobre as funções visuais. É comum a exposição ocupacional a esses tipos de substâncias, pois elas apresentam grande aplicabilidade em inúmeras atividades. Os efeitos podem ser quantificados por testes psicofísicos. Os testes mais usados nesse tipo de avaliação são de ordenamento de matizes, como o Teste D15 Dessaturado de Lanthony e o Teste dos 100 Matizes de Farnsworth-Munsell, e avaliação de sensibilidade ao contraste espacial de luminância, como MCT 8000 Vistech, VCTS 6500 Vistech e FACT 101. Em geral esses testes descrevem perda de discriminação de cores, afetando tanto o eixo azul-amarelo quanto o eixo verde-vermelho, e diminuição da sensibilidade ao contraste de luminância principalmente para as frequências espaciais mais baixas. Existe correlação positiva entre os resultados da avaliação psicofísica e vários marcadores biológicos e ambientais, mas essa correlação depende do marcador e do tipo de solvente ao qual os indivíduos são expostos. Fatores como alcoolismo crônico e tabagismo inveterado podem interferir no processo de correlacionar esses resultados.

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Objective: To correlate sleep apnea with craniofacial characteristics and facial patterns according to gender. Methods: In this prospective survey we studied 77 male and female children (3-12 years old) with an upper airway obstruction due to tonsil and adenoid enlargement. Children with lung problems, neurological disorders and syndromes, obstructive septal deviation, previous orthodontic treatment, orthodontic surgeries or oral surgeries, or obesity were excluded. Patients were subjected to physical examinations, nasal fiberoptic endoscopy, teleradiography for cephalometric analysis, and polysomnography. Methods: Cephalometric analysis included the following skeletal craniofacial measurements: facial axis (FA), facial depth (FD), mandibular plane angle (MP), lower facial height (LFH), mandibular arch (MA), and vertical growth coefficient (VERT) index. Results: The prevalence of sleep apnea was 46.75% with no statistical difference between genders. Among children with obstructive sleep apnea (Apneia Hypopnea Index - AHI >= 1) boys had higher AHI values than girls. A predominance of the dolichofacial pattern (81.9%) was observed. The following skeletal craniofacial measurements correlated with AHI in boys: FD (r(s) = -0.336/p = 0.020), MP (r(s) = 0.486/p = 0.00), and VERT index (r(s) = -0.337/p = 0.019). No correlations between craniofacial measurements and AHI were identified in girls. Conclusions: Craniofacial morphology may influence the severity of sleep apnea in boys but not in girls. (C) 2012 Elsevier B.V. All rights reserved.

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INTRODUCTION: In orthodontics, determining the facial type is a key element in the prescription of a correct diagnosis. In the early days of our specialty, observation and measurement of craniofacial structures were done directly on the face, in photographs or plaster casts. With the development of radiographic methods, cephalometric analysis replaced the direct facial analysis. Seeking to validate the analysis of facial soft tissues, this work compares two different methods used to determining the facial types, the anthropometric and the cephalometric methods. METHODS: The sample consisted of sixty-four Brazilian individuals, adults, Caucasian, of both genders, who agreed to participate in this research. All individuals had lateral cephalograms and facial frontal photographs. The facial types were determined by the Vert Index (cephalometric) and the Facial Index (photographs). RESULTS: The agreement analysis (Kappa), made for both types of analysis, found an agreement of 76.5%. CONCLUSIONS: We concluded that the Facial Index can be used as an adjunct to orthodontic diagnosis, or as an alternative method for pre-selection of a sample, avoiding that research subjects have to undergo unnecessary tests.

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[ES] Una vez expuestos los objetivos de la investigación definimos el término aptitud musical en toda su amplitud, nos acercamos a las características del adolescente para conocer el funcionamiento de su oído y adentrarnos en la legislación educativo musical de la Comunidad Valenciana. Realizamos un trabajo de campo con casi 2000 alumnos de 2º, 3º y 4º de Educación Secundaria de 15 centros educativos y les aplicamos dos pruebas: el test de aptitudes musicales de Seashore y el cuestionario de hábitos musicales de P.L. Nebreda. Una vez analizados los resultados observamos que la edad y el nivel educativo ejercen una influencia positiva en la discriminación de las aptitudes musicales, como también el hábito de escuchar música clásica y la práctica instrumental y vocal.

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In questo elaborato ho realizzato una breve analisi del concetto di 'Littérature-Monde' così come sostenuto da vari autori di lingua francese che rivendicano un mondo letterario più variegato e aperto, cosa che si realizzerebbe soprattutto nel pari riconoscimento tra scrittori francesi e scrittori francofoni: questi ultimi infatti sono stati per lungo tempo considerati ai margini della letteratura francese in quanto stranieri. Questa analisi è stata propedeutica per arrivare a capire il senso profondo del testo 'La cave de ma mémoire, le toit de ma maison sont des mots français' di Tahar Ben Jelloun, tratto dalla raccolta di testi "Pour une littérature-monde", che ho poi tradotto dal francese all'italiano.

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Die Romane der französischen Autorin Marie NDiaye (geb. 1967) sind durchzogen von Zuständen des Unwohlseins: NDiayes Protagonistinnen werden auf diffuse Weise sozial ausgegrenzt oder massiv bedrängt, verlieren die Kontrolle über ihren Körper oder geraten in schwindelerregende Zweifel über den Realitätsgehalt ihrer Sinneswahrnehmungen und Erinnerungen. Anhand der Romane "En famille" (1990), "Autoportrait en vert" (2005) und "Mon cœur à l’étroit" (2007) zeigt der Aufsatz, dass diese Momente des Unbehagens nicht nur die Suchbewegungen und Erkenntnisprozesse der Romanfiguren auslösen, sondern auch die kreative Spannung bilden, die den Vorgang der literarischen inventio in Gang setzt. Theoretische Modelle einer Psychologie, in der Unlust als Antrieb fungiert, finden sich bei Leibniz, Locke und Freud; Elemente einer Narratologie der Unlust, mit der sich die quête-Struktur von NDiayes Romanen beschreiben lässt, bietet die strukturalistische Märchentheorie Wladimir Propps und seiner Nachfolger.

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Ecological research and monitoring of lacustrine ecosystems often requires a whole-lake assessment of fish communities. Gillnet sampling offers an efficient means of estimating abundance, biomass and fish community composition. However the choice of gillnet sampling protocol may influence lake characterization via physical properties of the nets and allocation of sampling effort between littoral, benthic and pelagic habitats. This paper compares two commonly used, whole-lake sampling protocols applied across 17 prealpine, subalpine and alpine European lakes ranging widely in size, depth and altitude to determine their relative strength for research and management applications. Effort-corrected estimates of abundance, biomass and species richness were correlated between the protocols and both distinguished the trout-dominated alpine communities from subalpine and prealpine lakes dominated by whitefish and perch. A considerable amount of variance remained unexplained between the two protocols however, which seemed to correspond with differences in the proportion of effort among benthic and pelagic habitats. We suggest that both the European standard (CEN) and vertical (VERT) netting protocols are suitable for assessing ecological status and monitoring changes in lake fish communities through time. However the details of each protocol should be kept in mind when comparing fish communities between lakes. Mesh sizes used in CEN nets produce a more even size frequency distribution, suggesting that this protocol is most appropriate for assessing size structure of fish assemblages. The high proportion of netting effort in benthic habitats shallower than 70 m depth under the CEN protocol means that, particularly in larger lakes, outcomes will be disproportionately influenced by the ecological condition of this habitat. The VERT protocol presumably provides a more accurate estimate of whole-lake CPUE and community composition because effort, in terms of net area, is more evenly distributed across the entire volume of the lake. This is particularly important in large and deep lakes where pelagic habitats occupy a high proportion of the lake volume.

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The European standard for gillnetsampling to characterize lake fish communities stratifies sampling effort (i.e., number of nets) within depth strata. Nets to sample benthic habitats are randomly distributed throughout the lake within each depth strata. Pelagic nets are also stratified by depth, but are set only at the deepest point of the lake. Multiple authors have suggested that this design under-represents pelagic habitats, resulting in estimates of whole-lake CPUE and community composition which are disproportionately influenced by ecological conditions of littoral and benthic habitats. To address this issue, researchers have proposed estimating whole-lake CPUE by weighting the catch rate in each depth-compartment by the proportion of the volume of the lake contributed by the compartment. Our study aimed to assess the effectiveness of volume-weighting by applying it to fish communities sampled according to the European standard (CEN), and by a second whole-lake gillnetting protocol (VERT), which prescribes additional fishing effort in pelagic habitats. We assume that convergence between the protocols indicates that volume-weighting provides a more accurate estimate of whole-lake catch rate and community composition. Our results indicate that volume-weighting improves agreement between the protocols for whole-lake total CPUE, estimated proportion of perch and roach and the overall fish community composition. Discrepancies between the protocols remaining after volume-weighting maybe because sampling under the CEN protocol overlooks horizontal variation in pelagic fish communities. Analyses based on multiple pelagic-set VERT nets identified gradients in the density and biomass of pelagic fish communities in almost half the lakes that corresponded with the depth of water at net-setting location and distance along the length of a lake. Additional CEN pelagic sampling effort allocated across water depths and distributed throughout the lake would therefore help to reconcile differences between the sampling protocols and, in combination with volume-weighting, converge on a more accurate estimate of whole-lake fish communities.

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Afin d'étudier l'histoire de la végétation de l'Alpe d'Essertse, des sondages ont été effectués dans le Gouillé Rion, un étang situé à 2343 m d'altitude. Les grains de pollen contenus dans le sédiment lacustre ont été analysés palynologiquement. Le diagramme pollinique montre qu'après le retrait des glaciers vers 13000 BP (Before Present), l'Alpe d'Essertse fut colonisée par une végétation alpine et une végétation d'éboulis. Entre 9500 et 3600 BP le mélèze (Larix decidua) et l'arole (Pinus cembra) formaient une forêt qui atteignait au moins 2343 m. A partir de 5000 BP la forêt s'ouvrit et la limite de la forêt commença à s'abaisser. Des buissons d'aune vert (Alnus viridis) remplacèrent peut à peu la forêt. Entre 1700 et 900 BP seulement, cette végétation apparentée aux forêts fit place aux prés et pâturages. Seul l'utilisation d'autres méthodes permet d'estimer la limite d'altitude maximale atteinte par la forêt au cours de l'holocène: pour l'Alpe d'Essertse des charbons trouvés dans le sol, ainsi que des bioséquences pédologiques suggèrent une limite de la forêt maximale entre 2400 et 2450 m d'altitude.

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Mycobacterium tuberculosis strains of the Beijing lineage are globally distributed and are associated with the massive spread of multidrug-resistant (MDR) tuberculosis in Eurasia. Here we reconstructed the biogeographical structure and evolutionary history of this lineage by genetic analysis of 4,987 isolates from 99 countries and whole-genome sequencing of 110 representative isolates. We show that this lineage initially originated in the Far East, from where it radiated worldwide in several waves. We detected successive increases in population size for this pathogen over the last 200 years, practically coinciding with the Industrial Revolution, the First World War and HIV epidemics. Two MDR clones of this lineage started to spread throughout central Asia and Russia concomitantly with the collapse of the public health system in the former Soviet Union. Mutations identified in genes putatively under positive selection and associated with virulence might have favored the expansion of the most successful branches of the lineage.

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Jean Jacques Du Toit