289 research outputs found

    Estudio preliminar de unos restos de simios pliocénicos procedentes de "coda Bonica" (Gavá) (Prov. Barcelona)

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    Los materiales objeto de este estudio me han sido confiados por el Dr. J. F. DE VILLALTA, el cual agradezco aqui su amabilidad, así como el haber realizado la traducción del presente trabajo. La mandíbula pertenece al Instituto de Paleobiología del Consejo Superior de Investigaciones Científicas que dirige el Dr. L. VÍA y las dos piezas restantes, halladas por J. ULLASTREy A. MASRIERA, a las colecciones del Departamento de Ecología del Cuaternario del Instituto "Jaime Almera" (C.S.I.C.) de Barcelona. (...

    Evaluating causes of error in landmark-based data collection using scanners

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    In this study, we assess the precision, accuracy, and repeatability of craniodental landmarks (Types I, II, and III, plus curves of semilandmarks) on a single macaque cranium digitally reconstructed with three different surface scanners and a microCT scanner. Nine researchers with varying degrees of osteological and geometric morphometric knowledge landmarked ten iterations of each scan (40 total) to test the effects of scan quality, researcher experience, and landmark type on levels of intra- and interobserver error. Two researchers additionally landmarked ten specimens from seven different macaque species using the same landmark protocol to test the effects of the previously listed variables relative to species-level morphological differences (i.e., observer variance versus real biological variance). Error rates within and among researchers by scan type were calculated to determine whether or not data collected by different individuals or on different digitally rendered crania are consistent enough to be used in a single dataset. Results indicate that scan type does not impact rate of intra- or interobserver error. Interobserver error is far greater than intraobserver error among all individuals, and is similar in variance to that found among different macaque species. Additionally, experience with osteology and morphometrics both positively contribute to precision in multiple landmarking sessions, even where less experienced researchers have been trained in point acquisition. Individual training increases precision (although not necessarily accuracy), and is highly recommended in any situation where multiple researchers will be collecting data for a single project

    Quartz crystal reinforced silica glass obtained by Spark plasma sintering

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    Spark Plasma Sintering (SPS) presents a very low processing time when compared to conventional sintering methods. Such fast processing conditions allow it to control the grain size growth and preserve the powders distribution into the mold during sintering, which makes it possible to obtain graded and nano structured (using nano-powders) materials. High purity powders of vitreous silica and crystalline silica (alpha quartz) were sintered by the SPS process at temperature of 1350°C, which is higher than the annealing temperature of vitreous silica and below the temperature of quartz fusion. Such investigation showed the possibility to obtain high purity SiO2 material, which is a composite of silica glass matrix reinforced with crystalline alpha-quartz powder at almost any combination of volume fraction of matrix/reinforced structure, with well controlled reinforced grain size. X-ray diffraction and density measurements show the possibility to manufacture a unique glass-ceramic material of controlled crystallinity and density.CAPE

    COMPLICAÇÃO NA EXODONTIA DE TERCEIRO MOLAR SUPERIOR INCLUSO: DESLOCAMENTO PARA O SEIO MAXILAR - RELATO DE CASO

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                O deslocamento de terceiros molares superiores para dentro do seio maxilar é uma das complicações trans-operatórias que podem ocorrer quando a remoção destes dentes é realizada. O diagnóstico diferencial para análise da localização do dente deverá ser feita através de exames por imagens, averiguando a posição e o envolvimento deste com o seio maxilar, visto que há a possibilidade do elemento dentário estar deslocado para o espaço pterigopalatino. O trabalho apresenta o relato do caso da paciente O.S., submetida à cirurgia para remoção de um terceiro molar superior esquerdo incluso que foi deslocado para o interior do seio maxilar. A intenção é demonstrar como foi feito este diagnóstico, a técnica cirúrgica utilizada e o controle do caso a longo prazo. O acesso através da parede lateral do seio maxilar e a manutenção da lâmina cortical com levantamento da mucosa do seio mostra-se uma técnica eficiente, permitindo um bom reparo ósseo, demonstrado pela radiografia e pelo quadro clínico pós-operatório da paciente

    The Koskobilo (Olazti, Navarre, Northern Iberian Peninsula) paleontological collection: New insights for the Middle and Late Pleistocene in Western Pyrenees

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    The destroyed site(s) of Koskobilo (Olazti, Navarre, Northern Iberian Peninsula) have yielded unique archaeo-paleontological evidence in the Western Pyrenees region. The quarry uncovered a karstic site with faunal remains in 1940, and fossils were recovered both in situ and from the quarry dump. Ten years later, while the quarry was still working, a new visit to the dump yielded a large lithic assemblage and additional fossil remains with a different taphonomic pattern, which has been interpreted as the remains coming from a different site or zone within the same karst system. Here we re-study the paleontological evidence and provide new dating on a speleothem covering a Stephanorhinus hemitoechus tooth, which has yielded a minimum date of c. 220 ka for part of the assemblage. In total, the fossil assemblage comprises 38 mammal and six avian taxa and three fish remains. The faunal evidence indicates that in 1940 a mix of taxa from both the Middle and Upper Pleistocene were recovered, and it is difficult to assign most of them to a concrete period. However, based on biochronological criteria some of the identified taxa (e.g., Ursus thibetanus, Ursus cf. deningeri, Cuon cf. priscus, Macaca sylvanus, cf. Megaceroides) could be roughly contemporaneous with the dated rhino tooth, which would provide a new window to the Middle Pleistocene of the region, with deposits from MIS 7d and/or older. Despite the difficulties in studying this collection, recovered without stratigraphic context and in a salvage operation, Koskobilo has yielded an important paleontological assemblage which helps to understand the paleoecology of the Middle Pleistocene human occupations in the Western Pyrenees

    Extratos de Piper marginatum e Azadirachta indica no controle de Colletotrichum scovillei em pimentão

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    The objective of this work was to evaluate the effect of extracts of capeba (Piper marginatum) and neem (Azadirachta indica) on the fungus Colletotrichum scovillei, and evaluate the most active compound on the post‑harvest control of anthracnose in bell pepper. Methanolic extracts activity of leaves (P. marginatum and A. indica) and of seeds (A. indica) at 0, 125, 250, 500, 1,000, and 2,000 ppm, for in vitro inhibition of mycelial growth of C. scovillei, were evaluated. The methanolic extract of P. marginatum leaves was the most active and, consequently, it was subjected to a bioassay‑guided fractionation. This processing produced ten major compounds, obtained by preparative HPLC, from which the fraction at 1.5 ppm concentration was capable of inhibiting mycelial growth and was more effective than the fungicide mancozeb.O objetivo deste trabalho foi avaliar o efeito de extratos de capeba (Piper marginatum) e nim (Azadirachta indica) sobre o fungo Colletotrichum scovillei e determinar o componente mais ativo no controle pós‑colheita da antracnose em pimentão. A atividade de extratos metanólicos das folhas (P. marginatum e A. indica) e das sementes (A. indica) a 0, 125, 250, 500, 1.000 e 2.000 ppm, na inibição do crescimento micelial de C. scovillei in vitro foram avaliadas. O extrato metanólico de folhas de P. marginatum foi o mais ativo e, consequentemente, foi submetido ao fracionamento biomonitorado ("bioassay‑guided fractionation"). Esse processo rendeu 10 frações majoritárias, obtidas por cromatografia líquida de alta performance, das quais a fração à concentração de 1,5 ppm inibiu o desenvolvimento de C. scovillei de forma mais eficiente do que o fungicida mancozeb

    Serial analysis of circulating tumor cells in metastatic breast cancer receiving first-line chemotherapy

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    Background: We examined the prognostic significance of circulating tumor cell (CTC) dynamics during treatment in metastatic breast cancer (MBC) patients receiving first-line chemotherapy. Methods: Serial CTC data from 469 patients (2,202 samples) were used to build a novel latent mixture model to identify groups with similar CTC trajectory (tCTC) patterns during the course of treatment. Cox regression was used to estimate hazard ratios for progression-free survival (PFS) and overall survival (OS) in groups based on baseline CTCs (bCTC), combined CTC status at baseline to the end of cycle 1 (cCTC), and tCTC. Akaike Information Criterion (AIC) was used to select the model that best predicted PFS and OS. Results: Latent mixture modeling revealed 4 distinct tCTC patterns: undetectable CTCs (tCTCneg, 56.9% ), low (tCTClo, 23.7%), intermediate (tCTCmid, 14.5%), or high (tCTChi, 4.9%). Patients with tCTClo, tCTCmid and tCTChi patterns had statistically significant inferior PFS and OS compared to those with tCTCneg (P<.001). AIC indicated that the tCTC model best predicted PFS and OS when compared to bCTC and cCTC models. Validation studies in an independent cohort of 1,856 MBC patients confirmed these findings. Further validation using only a single pretreatment CTC measurement confirmed prognostic performance of the tCTC model. Conclusions: We identified four novel prognostic groups in MBC based on similarities in CTC trajectory patterns during chemotherapy. Prognostic groups included patients with very poor outcome (tCTCmid+tCTChi, 19.4%) who could benefit from more effective treatment. Our novel prognostic classification approach may be utilized for fine-tuning of CTC-based risk-stratification strategies to guide future prospective clinical trials in MBC
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