Determinação da Porosidade e Permeabilidade do Sistema Aquífero Urucuia Centro-Ocidental através da Interpretação de Perfis Geofísicos

Nos estudos hidrogeológicos, a porosidade e permeabilidade caracterizam as rochas em relação ao armazenamento e a transmissão de fluidos nos aquíferos. Neste trabalho, os parâmetros petrofísicos foram obtidos através das informações contidas em cinco perfis geofísicos de poços com a integração dos dados do tempo de trânsito das ondas acústicas e da contagem em unidades API (American Petroleum Institute) dos raios gama. Nesse contexto, a área de estudo compreende uma associação de duas unidades hidroestratigráficas inter-relacionadas (Formações Posse e Serra das Araras) com características hidráulicas específicas, individualizadas por propriedades petrofísicas e sedimentológicas contrastantes ao longo de sua área de abrangência, segundo uma orientação de ENE (área fonte) para WSW (área deposicional). Nesse trend, a variação das propriedades petrofísicas sugere que os principais resultados obtidos indicam: (i) um aumento nos valores médios de argilosidade (VSH) para a Formação Posse e, consequentemente, uma diminuição na porosidade total (φ) devido ao processo de infiltração mecânica das argilas que funcionam como uma pseudomatriz dos arenitos eólicos, caracterizado por um aumento da VSH com a profundidade. Já os parâmetros porosidade efetiva (φe) e permeabilidade (ƙ) apresentam uma tendência de aumento em razão de um maior grau de seleção das partículas do arcabouço; (ii) para a Formação Serra das Araras é verificado uma diminuição no VSH ao longo de sua extensão, devido a uma maior variação litológica, e em profundidade, como uma consequência de uma infiltração mecânica das argilas intersticiais para a unidade subjacente. Na porção centro-oriental da bacia hidrogeológica ocorre uma diminuição significativa nos valores médios de φ, φe e ƙ devido a uma maior frequência e espessura de níveis silicificados e fraturados que compõe o Sistema Aquífero Urucuia (SAU). De modo geral, os parâmetros petrofísicos se relacionam a dois importantes reservatórios do SAU – Aquífero Posse e Aquífero Serra das Araras – permoporosos, contíguos e segmentados por níveis/horizontes silicificados e fraturados que representam aquitardes e, provavelmente, conferem uma conexão hidráulica (i.e., drenança) entre as unidades litoestratigráficas

Evaluation of the microleakage of occlusal sealant in deciduous enamel teeth: effect of different application techniques

Objetivos: Considerando que os dentes decíduos são mais propensos ao desenvolvimento de cárie dentária, este estudo teve como objetivo comparar o efeito de diferentes técnicas de aplicação de selante de fóssulas e fissuras, isoladas ou associadas, na microinfiltração de esmalte em molares de dentes decíduos. Materiais e métodos: dentes molares decíduos foram sele­cionados (n = 8) e receberam os seguintes tratamentos: 1) grupo controle: condicionamento ácido + selante; 2) ar abrasivo + condicionamento ácido + selante; 3) condicionamento ácido + adesivo + selante; 4) ar abrasivo + condicionamento ácido + adesivo + selante. Após o tratamento, os dentes foram imersos em água destilada a 37 °C por sete dias e então submetidos a termociclagem de 350 ciclos de banhos de água fria (5 °C) e quente (55 °C), com 30 segundos cada exposição. Posterior­mente, os dentes foram cobertos com um verniz – deixando exposta apenas a área selada, estendida por 1 mm –, imperme­abilizados com resina epóxica e imersos em solução de azul de metileno por 48 horas a 37 °C. Em seguida, os dentes foram seccionados vestíbulo-lingualmente e avaliados microscopicamente (aumento de 40×). Os resultados foram submetidos aos testes de Kruskal-Wallis e de Mann-Whitney (p < 0,05). Resultados: os grupos que receberam o adesivo antes da apli­cação do selante apresentaram o menor índice de microinfiltração. O grupo que recebeu ar abrasivo mais condicionamento ácido antes do selante mostrou microinfiltração mais extensa. Conclusões: nenhuma das técnicas utilizadas evitou comple­tamente a microinfiltração, entretanto a aplicação de adesivo pode ser a mais indicada.Objectives: Since deciduous teeth are more prone to the development of dental decay, this study aimed to compare the effect of different strategies for sealant application in pits and fissures, whether isolated or associated, on the enamel microleakage in molars of deciduous teeth. Materials and methods: deciduous teeth molars were selected (n = 8) and received the following treatments: 1) control group: acid etching + sealant; 2) abrasive air + acid etching + sealant; 3) acid etching + adhesive + sealant; 4) abrasive air + acid etching + adhesive + sealant. After treatment, the teeth were immersed in distilled water at 370 °C for seven days and subjected to thermocycling of 350 cycles of cold (5 °C) and hot (55 °C) baths, for 30 seconds in each exposure. Afterwards, the teeth were covered with varnish – leaving only the sealed area exposed, extended by 1 mm –, waterproofed with epoxy resin and immersed in methylene blue solution for 48 hours at 37 °C. Then, the teeth were buccal-lingually sectioned and microscopically evaluated (40× magnification). The results were subjected to the Kruskal-Wallis and to the Mann-Whitney tests (p < 0.05). Results: the groups that received the adhesive prior to the sealant ap­plication have presented the lowest index of microinfiltration. The group that received abrasive air and acid etching before the sealant have showed more extensive microleakage. Conclusions: none of the techniques conducted herein have completely avoided the microle­akage, however the adhesive application may be the most indicated technique

Taking the pulse of Earth's tropical forests using networks of highly distributed plots

Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen Los bosques tropicales son los ecosistemas más diversos y productivos del mundo y entender su funcionamiento es crítico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. Aquí mostramos cómo una comunidad global está respondiendo a los desafíos de la investigación en ecosistemas tropicales a través de diversos equipos realizando mediciones árbol por árbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos más importantes de este trabajo y discutimos cómo este proceso está cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexión de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a múltiples escalas. Conectando investigadores tropicales, elevando su posición y estatus, nuestro modelo de Red Social de Investigación reconoce el rol fundamental que tienen, para el descubrimiento científico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (Suramérica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiático (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas están integradas a través de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 países en 24 redes diferentes de parcelas. Colectivamente, estas redes están transformando nuestro conocimiento sobre los bosques tropicales y el rol de éstos en la biósfera. Juntos hemos descubierto cómo, dónde y porqué el carbono y la biodiversidad de los bosques tropicales está respondiendo al cambio climático y cómo se retroalimentan. Esta colaboración pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuáles son los factores más importantes, qué procesos se ven afectados, dónde ocurren los cambios, los tiempos de reacción y las probables respuestas futuras mientras el clima continúa cambiando. Apalancando lo que realmente es una tecnología antigua, las redes de parcelas están generando una verdadera y moderna revolución en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar información única y de largo plazo para entender los que probablemente son los bosques más preciados de la tierra. Resumo Florestas tropicais são os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensão destas florestas seja crucial para o nosso futuro coletivo, até muito recentemente os esforços de medições e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agências financiadoras. Neste estudo nós mostramos como uma comunidade global está respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, árvore por árvore, em milhares de parcelas monitoradas à longo prazo. Nós revisamos as maiores descobertas científicas deste trabalho, e mostramos também como este processo está mudando a ciência de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta científica. Concebida em 1999 com o RAINFOR (América do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiático (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas múltiplas iniciativas estão integradas através de uma infraestrutura cibernética do ForestPlots.net, conectando colegas de 54 países de 24 redes de parcelas. Estas iniciativas estão transformando coletivamente o entendimento das florestas tropicais e seus papéis na biosfera. Juntos nós descobrimos como, onde e por que o carbono e a biodiversidade da floresta estão respondendo às mudanças climáticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendências, assim como tem evidenciado quais direcionadores são mais importantes, quais processos florestais são mais afetados, onde eles estão mudando, seus atrasos no tempo de resposta, e as prováveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notável tecnologia antiga, redes de parcelas acendem faíscas de uma moderna revolução na ciência das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora são coletivamente capazes de gerar conhecimentos únicos e duradouros sobre as florestas mais preciosas da Terra. Résume Les forêts tropicales sont les écosystèmes les plus diversifiés et les plus productifs de la planète. Si une meilleure compréhension de ces forêts est essentielle pour notre avenir collectif, jusqu'à tout récemment, les efforts déployés pour les mesurer et les surveiller ont été largement déconnectés. La mise en réseau est essentielle pour découvrir les réponses à des questions qui dépassent les frontières et les horizons des organismes de financement. Nous montrons ici comment une communauté mondiale relève les défis de la recherche sur les écosystèmes tropicaux avec diverses équipes qui mesurent les forêts arbre après arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales découvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forêts tropicales. Notre approche principale consiste à relier les initiatives de base à long terme à des protocoles standardisés et une gestion de données afin de générer des résultats solides à grande échelle. En reliant les chercheurs tropicaux et en élevant leur statut, notre modèle de réseau de recherche sociale reconnaît le rôle clé de l'auteur des données dans la découverte scientifique. Conçus en 1999 avec RAINFOR (Amérique du Sud), nos réseaux de parcelles permanentes ont été adaptés à l'Afrique (AfriTRON) et à l'Asie du Sud-Est (T-FORCES) et largement imités dans le monde entier. Ces multiples initiatives sont désormais intégrées via l'infrastructure ForestPlots.net, qui relie des collègues de 54 pays à travers 24 réseaux de parcelles. Ensemble, elles transforment la compréhension des forêts tropicales et de leur rôle biosphérique. Ensemble, nous avons découvert comment, où et pourquoi le carbone forestier et la biodiversité réagissent au changement climatique, et comment ils y réagissent. Cette collaboration pan-tropicale à long terme a révélé un important puits de carbone à long terme et ses tendances, tout en mettant en évidence les facteurs les plus importants, les processus forestiers qui sont affectés, les endroits où ils changent, les décalages et les réactions futures probables des forêts tropicales à mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les réseaux de parcelles déclenchent une révolution très moderne dans la science des forêts tropicales. À l'avenir, l'humanité pourra grandement bénéficier du soutien des communautés de base qui sont maintenant collectivement capables de générer une compréhension unique et à long terme des forêts les plus précieuses de la Terre. Abstrak Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia

Identification and Analysis of the Fluoride Concentration in Toothpastes Intended for Children

Objective:To identify the commercially available toothpastes intended for children and their total soluble fluoride concentrations (TSF). Material and Methods:Twelve brands of toothpastes intended for children marketed in supermarkets and pharmacies were found and analyzed: Bitufo®; Colgate Smile®; Lilica Ripilica®; Even Baby®; Turma da Mônica Baby®; Loney Tunes®; Loney Tunes Baby®; Malvatrikds Baby®; Oral B Stages®; Sanifil Kids®; Tandy®; Tra-lá-lá Baby®. Duplicate samples of each toothpaste were weighed (+/- 90 to 110 mg) and diluted in 10 mL of distilled water under stirring. To evaluate soluble fluoride, duplicate aliquots of supernatant suspensions were evaluated on specific ion fluoride electrode calibrated with fluoride standard solutions and results expressed in ppm F according to established protocol. Results:According to information provided by manufacturers, 5 non-fluoridated toothpastes, 3 toothpastes with less than 1000 ppm F and 4 toothpastes with conventional fluoride concentration (1100 ppm F) were identified. After analysis of soluble fluoride of fluoridated toothpastes, only 02 presented TSF concentration equal to or greater than 1000 ppm F. The TSF concentration (mean ± SD) for all samples ranged from 8.2 ± 0.1 to 1065.9 ± 24.7 ppm F. Conclusion:Few toothpastes intended for children presented soluble fluoride concentrations capable of preventing dental caries. Additionally, regulatory measures need to be implemented for the marketing of toothpastes intended for children with at least 1000 ppm of soluble fluoride, especially in locations without other sources of fluoride (fluoridated water) for the population

Study on Morphological Changes and Interference in the Development of <i>Aedes aegypti</i> Caused by Some Essential Oil Constituents

Dengue, Chikungunya and Zika are arboviruses, transmitted by the mosquito Aedes aegypti, that cause high mortality and serious health consequences in human populations. Efforts to control Ae. aegypti are important for preventing outbreaks of these diseases. Essential oil constituents are known to exhibit many activities, such as their use as larvicides. Given their potential, the present study aimed to characterize the larvicidal effect of dihydrojasmone, p-cymene, carvacrol, thymol, farnesol and nerolidol on the larvae of Ae. aegypti and their interference over the morphology of the mosquitos. The essential oil constituents were dissolved in dimethylsulfoxide at concentrations of 1–100 μg/mL and were applied in the breeding environment of third-stage larvae. The larvae from bioassays were fixed, dehydrated and embedded. Ultrathin sections were contrasted using 5% uranyl acetate and 1% lead citrate for observation through transmission electron microscopy. The oil with the highest larvicidal efficiency was found to be nerolidol, followed by farnesol, p-cymene, carvacrol, thymol and dihydrojasmone, with an LC50 of 11, 21, 23, 40, 45 and 66 µg/mL, respectively. The treated Ae. aegypti larvae caused alteration to the tegument or internal portions of larvae. The present study demonstrated which of these oils—dihydrojasmone, farnesol, thymol, p-cymene, carvacrol and nerolidol—have effective larvicidal activity

Spectrophotometric assessment of tooth bleaching under orthodontic braquets bonded with different materials

<div><p>Abstract Introduction patients have been submitted to tooth bleaching during orthodontic treatment for aesthetic purposes or to anticipate the replacement of restorations after completion of the treatment. Objective to evaluate the effectiveness of tooth bleaching under orthodontic brackets bonded with different materials. Material and method a hundred bovine enamel blocks were divided into two groups, at-home and in-office tooth bleaching. In-office bleaching was subdivided into five groups (n = 10): HP (control - without brackets); SA(t) - brackets bonded with Transbond XT, without bleaching; SA(fm) - brackets bonded with Orthodontic Fill Magic, without bleaching; HP(t) - brackets bonded with Transbond XT subjected to bleaching; and HP(fm) - brackets bonded with Orthodontic Fill Magic subjected to bleaching. At-home bleaching followed the same treatments, only replacing the bleaching agent. Spectrophotometric assessment was used for tooth color determination at three moments: 1) before staining (baseline); 2) after staining; 3) after bonding the brackets and bleaching procedures. Data were submitted to ANOVA and analyzed by Tukey's test (p < 0.05). Result For both types of bleaching, the control group had an effective bleaching action. Groups using Transbond XT presented greater bleaching potential among the groups with orthodontic accessory, but the bleaching action differed from the positive control. Groups using Orthodontic Fill Magic presented no bleaching action, resembling the negative control groups (artificial saliva). Conclusion the orthodontic bracket impaired the effectiveness of the at-home and in-office bleaching treatment, regardless of the resin used for bonding.</p></div

Analysis of oral health conditions and risk factors for dental caries in patients with sickle cell disease

Objective: To analyze the oral health conditions and risk factors for caries in patients with sickle cell disease. Methods: An observational, cross-sectional study was conducted in the clinic of the Association of Persons with Hemoglobinopathies of Alagoas, in the city of Maceió-AL, Brazil. The sample composed of 43 patients were included by census sampling. The ICDAS/DMFT/dmf-t caries indices were used, and simplified oral hygiene, salivary flow and buffer capacity tests were performed. Patients were interviewed to check their level of knowledge about oral hygiene and diet. Spearman correlation and ANOVA statistical tests were applied (p<0.05). Results: The mean DMFT was 15.49±4.43; oral hygiene regular (IHOS=2.22±0.18); mean salivary flow 0.92±0.26, and mean buffer capacity 4.60±0.32. Correlation was found between salivary flow and buffer capacity (p = 0.009). Patients with the highest caries prevalence, in the age-ranges 6 to 12, and 20 to 26 years, had the lowest buffer capacity values (p = 0.04). Interviews showed that 58% did not use dental floss, 88% consumed cariogenic snacks, 100% reported never having received guidance from dentists about the cariogenic potential of foods and 60% reported the use of anticholinergic medications to reduce drooling (Tramal® and morphine) during pain crises. Conclusion: These patients presented extremely high caries prevalence, with predominance of carious teeth. The salivary parameters analyzed and level of knowledge about oral hygiene and cariogenic diet presented, showed that patients with sickle cell disease belonged to a group with risk for development of dental caries