The locomotion pattern of Baurusuchus salgadoensis Carvalho, Nobre & Campos, 2005 and the distribution of Baurusuchidae in Gondwanaland

Baurusuchus salgadoensis Carvalho, Nobre & Campos, 2005 is a ziphodont mesoeucrocodylian closely related to the Sebecosuchia. Cranial features indicate that this species had terrestrial predatory habits. The postcranial skeleton of B. salgadoensis show distinctive characteristics when compared to extant Crocodylomorpha. The dorsal vertebrae are close articulated with short and craniocaudally expanded neural spines, specially the posterior ones. The sacral vertebrae are robust and have the lateral processes highly fused to the ilium. The anterior caudal vertebrae are robust as the sacral ones but their neural spines are more stout, anteriorlly expanded and higher. The close articulation of the dorsal vertebrae may indicate a less flexible dorsal spine, ideal to limb-driven methods of locomotion. The high and expanded neural spines of the posterior dorsal and sacral vertebrae are associated to muscle attachment from the osteoderms and the pelvic musculature, all used in the limb-driven locomotion. The appendicular bones of B. salgadoensis are long and stout. They show a straight aspect of their diaphysis and very well- developed epiphysis. The femur is long when compared to extant crocodilians, showing a straight aspect in lateral view and a slight sigmoid aspect in frontal view. There is a small axial torsion at its proximal end. The fourth trochanter is pronouced and posteriorlly oriented. The proximal end possess a mesial projection that articulates itself to the illium, similar to those of Protosuchia and thecodont archosaurs as the Rauisuchia. The illium of B. salgadoensis present a lateral and posteriorlly expanded postaccetabular crest, similar to those observed in Rauisuchia and Protosuchia, referred as overhanging ilium. This pattern of articulation is observed in the rauisuchian thecodonts and interpreted as a characteristic trait of those able erect-posture and limb-driven predators of Triassic environments. B. salgadoensis exoskeleton has only two dorsal osteoderm rows that run from the neck to the tip of the tail. Most of the osteoderms are wider than longer, with a round lateral portion that does not articulate to any flank osteoderm. The only morphological difference appears at the caudalmost portion of the tail, where the osteoderms are craniocaudally elongated. The medial portion has little variation along the scutes rows and may bear medial lamellar dorsoventral structures of articulation to the adjacent bony plate. The anterior articular facet is discreet and the osteoderms are not as imbricated as occur in other crocodyliforms and even may not be imbricated at all. The pelvic region osteoderms have the tallest keel of the row that runs from the anterior articular facet to posteriosmost portion of the osteoderm. B. salgadoensis has a light exoskeleton and then is less encumbranced by it. Therefore, becaming more agile. The imbrication of dorsal armor assists the limb-driven locomotion of many crocodyliform by reducing the flexibility of the dorsal spine during the high-walk (erect stance). Therefore the long and stout limb bones, overhanging crest of the illium and the light weighted armor, also allowed to B. salgadoensis to have the limb-driven locomotion without this pattern of osteoderms. These anatomical data may indicate how the Baurusuchidae had a wide distribution in Gondwanaland as they were able to move across large distances

Occurrence of Gastroliths in _Baurusuchus_ (Baurusuchidae, Mesoeucrocodylia) from Adamantina Formation, Bauru Basin

The fossil record of Baurusuchidae Mesoeucrocodylia in the General Salgado county and its surroundings is one of the best regarding preservation, completeness and articulation of skull and skeleton remains, including specimens that shown even the most delicate bone structures and cartilaginous tissues. 

One of them, UFRJ DG 288-R, has preserved its skull and about 80% of its skeleton. During the removal of the rock matrix, on what should be the specimen’s abdominal region, together with fragments of gastralia were observed some small well-polished weathered angulous to subrounded clasts, presumed to be gastroliths. 

These xenoliths occur in a restrict cluster, where at least four peeble-sized stones are visible in the surface of the specimen. The texture and fabrics of these rock fragments differs from the surrounding matrix, presenting darker purplish tones. In thin section, one of the fragments revealed isotropic texture, with opaque minerals in abundance, of euhedric to subhedric habits. The mineralogical composition presents mainly clay minerals as weathering products; biotite and chlorite are common, being the last the result of hidratation of the first. Although highly altered, the low quartz content, small-sized and well-formed crystals suggests maphic composition in volcanic context, possibly representing a basalt fragment. 

In extant Crocodyliformes, the occurrence of gastroliths is commonly associated with food processing in the stomach, diving ballast, hunger stress and/or supplementary mineral ingestion. 

As baurusuchids are characterized as medium to large size fully terrestrial predator/scavengers, based on skeletal data, the ballast function of gasthroliths is excluded in this case. As mentioned above, extant crocodyliforms such as _Caiman_ and _Crocodylus_ ingest stones when under stressful conditions of lack of food, water or when in high population density. Osteoderms are one of the primary sources for calcium and a reservoir for the homeostasis. The hunger stress can be observed in the osteoderms histological cuts as an abnormal concentration of osteoclasts at its inner region overwhelming the presence of osteoblasts and consuming the osteocytes. The preservation of osteoderms associated with gasthroliths may reveal if the stone ingestion in baurusuchids is a normal or driven by hunger behavior. 

The paleoenvironmental conditions dominating the Adamantina Formation during the Late Cretaceous are considered mainly arid, marked with strong seasonality, alternating long droughts and short rainy periods, associated with flashflood events. The stressful condition created during the dry season would cause famine and mass mortality, thus forcing animals to endure or escape. The baurusuchids underwent the dry seasons through behavorial responses of self burial and probably stone ingestion, although natural bahavior cannot be eliminated as a cause. 

Financial support provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, grant no 305780/2006–9), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Instituto Virtual de Paleontologia/ Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (IVP/FAPERJ, grant no E–26/152.541/2006).
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Modelo físico de Huygens na solução discretizada de campos acústicos

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Mecânica, Florianópolis, 2013.O objetivo geral deste trabalho é demonstrar a viabilidade de aplicação numérica do modelo físico de Huygens na descrição de ondas acústicas. Uma ampla revisão bibliográfica sobre o assunto foi realizada, incluindo trabalhos na área de Eletromagnetismo, contexto em que a primeira versão discretizada do modelo de Huygens foi proposta, utilizando a consolidada teoria de linhas de transmissão. Entretanto, ainda que o método tenha se desenvolvido consideravelmente em seu contexto original, percebe-se que as aplicações na solução de problemas em Acústica ainda são escassas. Inicialmente, dedica-se um capítulo para discorrer sobre os fundamentos da modelagem numérica, expondo as razões principais que levaram a escolha do tema do trabalho. Posteriormente, alguns tópicos fundamentais relacionados à teoria de processamento de sinal e auralização foram incluídos. A seguir é apresentada a abordagem teórica pioneira do método numérico, concebida a partir do modelo de Huygens, denominada de Método de Matrizes de Linha de Transmissão (TLM). Neste ponto, buscou-se revisar as analogias tradicionalmente estabelecidas com a teoria Acústica. Posteriormente, demonstram-se os aspectos teóricos de uma nova abordagem energética mecanicista para o modelo, denominada de Modelagem Discreta de Huygens (DHM). Em um passo seguinte, foram realizadas comparações conceituais entre a Modelagem Discreta de Huygens e outros métodos numéricos tradicionais, como o método de Volumes Finitos e também aqueles que utilizam como base a equação da onda, tais como Diferenças Finitas (FDM) e Elementos Finitos (FEM). Por último, apresenta-se uma série de resultados utilizando o conjunto de algoritmos desenvolvidos ao longo deste trabalho. Destacam-se as análises comparativas entre os tempos de simulação obtidos pelos métodos FEM e DHM para três cavidades distintas. Resultados relevantes também foram obtidos utilizando uma metodologia diferenciada para representação do coeficiente de reflexão de materiais de absorção no domínio do tempo, a partir de dados de impedância no domínio da frequência. Buscou-se estabelecer a comparação dos resultados obtidos, com modelos elaborados em FEM, assim como através de modelos analíticos consolidados, visando a confirmação das evidências iniciais quanto à potencialidade do método. Abstract : The main idea of this work is to show the feasibility of applying the Huygens' physical model for the numerical description of acoustic wave propagation. A extensive literature review on the subject was performed, including some work in the field of electromagnetism, using the consolidated theory of transmission lines. Although the method has been considerably developed in their original area, applications in solving acoustic problems are still quite scarce. A chapter was dedicated to discuss the fundamentals of numerical modeling, explaining the reasons that led to the choice made for this work. Fundamental topics related to signal processing and auralization were also included. In the following, the pioneering numerical approach based on the Huygens' physical model is presented, called Transmission Line Matrix, seeking to make analogies with the acoustics theory. Subsequently, it was shown the theoretical aspects of the energetical approach to the Huygens' model, called Discrete Huygens' Modeling. In a next step, comparisons were made among the concepts of this approach and other numerical methods that apply the wave equation as the fundamental model, such as finite difference and finite element. Following, results were presented using an algorithm developed as consequence of this work, in order to solve acoustic cavities of different sizes, and then compare with results obtained from numerical models simulated using finite element and analytical models. In the Annex, some data already published by different authors for acoustical problems were considered in order to emphasize the range of applications and the quality of results

Efficacy of nano-hydroxyapatite on caries prevention-a systematic review and meta-analysis.

Introduction/objectives: The review systematically explored in vivo or in situ studies investigating the efficacy of nano-hydroxyapatite (nHA) to reduce initiation of or to remineralize initial caries lesions. Data: Prospective controlled (non-)randomized clinical trials investigating the efficacy of a nHA compared to any other (placebo) treatment or untreated/standard control. Sources: Three electronic databases (Central Cochrane, PubMed-MEDLINE, Ovid EMBASE) were screened. Outcomes were, e.g., ICDAS score, laser fluorescence, enamel remineralization rate, mineral loss, and lesion depth. No language or time restrictions were applied. Risk of bias and level of evidence were graded using the Risk of Bias 2.0 tool and GRADE profiler. Study selection/results: Five in vivo (and 5 in situ) studies with at least 633 teeth (1031 specimens) being assessed in more than 420 (95) patients were included. No meta-analysis could be performed for in vivo studies due to the high heterogeneity of the study designs and the variety of outcomes. In situ studies indicate that under demineralization conditions, NaF was able to hinder demineralization, whereas nHA did not; simultaneously, nHA did not differ from the fluoride-free control. In contrast, under remineralizing conditions, nHA and NaF show the same remineralizing potential. However, the level of evidence was very low. Furthermore, six studies showed a high risk of bias, and six studies were funded/published by the manufacturers of the tested products. Conclusion: The low number of clinical studies, the relatively short follow-up periods, the high risks of bias, and the limiting grade of evidence do not allow for conclusive evidence on the efficacy of nHA. Clinical relevance: No conclusive evidence on the efficacy of nHA could be obtained based on the low number of clinical studies, the relatively short follow-up periods, the high risks of bias, the limiting grade of evidence, and study conditions that do not reflect the everyday conditions

Impact of traumatic dental injuries and malocclusions on quality of life of young children

<p>Abstract</p> <p>Background</p> <p>The presence of traumatic dental injuries and malocclusions can have a negative impact on quality of life of young children and their parents, affecting their oral health and well-being. The aim of this study was to assess the impact of traumatic dental injuries and anterior malocclusion traits on the Oral Health-Related Quality of Life (OHRQoL) of children between 2 and 5 years-old.</p> <p>Methods</p> <p>Parents of 260 children answered the six domains of the Early Childhood Oral Health Impact Scale (ECOHIS) on their perception of the OHRQoL (outcome). Two calibrated dentists assessed the types of traumatic dental injuries (Kappa = 0.9) and the presence of anterior malocclusion traits (Kappa = 1.0). OHRQoL was measured using the ECOHIS. Poisson regression was used to associate the type of traumatic dental injury and the presence of anterior malocclusion traits to the outcome.</p> <p>Results</p> <p>The presence of anterior malocclusion traits did not show a negative impact on the overall OHRQoL mean or in each domain. Only complicated traumatic dental injuries showed a negative impact on the <it>symptoms </it>(p = 0.005), <it>psychological </it>(p = 0.029), <it>self image/social interaction </it>(p = 0.004) and <it>family function </it>(p = 0.018) domains and on the overall OHRQoL mean score (p = 0.002). The presence of complicated traumatic dental injuries showed an increased negative impact on the children's quality of life (RR = 1.89; 95% CI = 1.36, 2.63; p < 0.001).</p> <p>Conclusions</p> <p>Complicated traumatic dental injuries have a negative impact on the OHRQoL of preschool children and their parents, but anterior malocclusion traits do not.</p

Interpretation of magnetic data based on euler deconvolution : analysis of the main host gold structure in the northeastern portion of the Quadril?tero Ferr?fero, MG, Brazil.

The study of the geometry and kinematics of deep geological structures, bearing mineralization, has advanced greatly by the aggressive progress of geophysical techniques over the last decades. The gold mineralization located in the Quadril?tero Ferr??fero has its genesis controlled by shear zones. The geophysical analysis (aeromagnetic and aero-electromagnetic) by means of two-dimensional magnetic data inversion profiles (Euler deconvolution) and later interpolation, provided the 3D configuration of a tectonic-structural geological model, explaining the spatial configuration of lithostratigraphic and structural units, and kinematics features of the main shear zone mineralized in gold in the northeastern portion of the Quadril?atero Ferr??fero. The processing of airborne geophysical magnetic data of the Rio das Velhas Project provided the generation of inversion profiles with outputs up to 5000 m deep, opening new windows for gold prospection at the surroundings of the main gold mineralized structure in the Quadril?atero Ferr?fero. The integration of geological, geophysical data and field observations was essential for the final results of this work.O estudo da geometria e cinem?tica de estruturas geol?gicas de alta profundidade, portadoras de mineraliza??es, tem sido cada vez mais viabilizado pelo avan?o agressivo das t?cnicas geof?sicas nas ultimas d?cadas. As mineraliza??es de ouro localizadas no Quadril?atero Ferr?fero t?em a sua g?nese controlada por zonas de cisalhamento. A an?lise geof?sica (magnetometria e eletromagnetometria de dados aerolevantados) atrav?s de perfis de invers?o bidimensionais (deconvolu??o de Euler) e posterior interpola??o, possibilitou a configura??o 3D de um modelo geol?gico tectono-estrutural, que permitisse uma an?lise e sugest?o descritiva da configura??o espacial de unidades litoestratigr?ficas, estruturais e cinem?tica da principal zona de cisalhamento mineralizada em ouro do nordeste do Quadril?tero Ferr?fero. O processamento de dados magnetom?tricos aerogeof?sicos do Projeto Rio das Velhas possibilitou a gera??o de perfis de invers?o com respostas de at? 5000 m de profundidade, abrindo novas janelas para a prospec??o de ouro nas adjac?ncias da principal estrutura mineralizada em ouro do Quadril?atero Ferr?fero. A integra??o de dados geol?gicos, aerogeof?sicos e de observa??es de campo foi fundamental para os resultados finais deste trabalho

Design, development and validation of a questionnaire to assess dentists' knowledge and experience in diagnosing, recording, and managing root caries.

OBJECTIVES The prevalence of root caries is increasing globally, especially in the elderly population, and even though the number of patients with root caries lesions is augmenting, there are still many discrepancies in how dentists manage this condition. The present study aimed to develop and validate a questionnaire to evaluate how dentists diagnose, record and manage root caries lesions, and to verify the validity and reliability of this questionnaire. MATERIALS AND METHODS An expert panel developed a self-administered questionnaire survey with three domains: (1) dentists' knowledge on diagnosis, recording, and managing root caries; (2) information about their current general clinical routines; (3) their demographics. The original English [E] version was translated into three different languages (French [F], German [G], Italian [I]), and subsequently back-translated into English by independent dentists. For the validation, 82 dentists (20-22 for each of the translated versions) accepted to answer the questionnaire at two different time-points (with 1-week interval). The data was quality checked. Construct validity, internal reliability, and intra-class correlation (ICC) were assessed. RESULTS Seventy-seven dentists completed the questionnaire twice [E: 17; F: 19; G: 19; I: 22]. The mean ICC (standard deviation) was 0.98(0.03) for E, 0.90(0.12) for F, 0.98 (0.04) for G, and 0.98 (0.01) for I. Overall, the test-retest reliability was excellent (mean ICC (SD): 0.96 (0.08)). Furthermore, the questionnaire demonstrated good internal reliability (inter-observer reliability; Fleiss kappa: overall:0.27(fair); E:0.30 (fair); F: 0.33(fair); G: 0.33(fair); I: 0.89 (almost perfect)). CONCLUSION The questionnaire was validated and is suitable to be used in the four languages to assess the knowledge of dentists on diagnosing, recording and managing root caries. CLINICAL SIGNIFICANCE The present questionnaire was validated and seems to be a good tool to evaluate how dentists diagnose, record, and manage root caries lesions both in its original (English) and its translated (French, German, and Italian) versions