957 resultados para facial expressions


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Neuroblastoma (NB) is a common pediatric tumor that exhibits a wide range of biological and clinical heterogeneity. EPH (erythropoietin-producing hepatoma amplified sequence) family receptor tyrosine kinases and ligand ephrins play pivotal roles in neural and cardiovascular development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6) and its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is associated with low-stage NB (stages 1, 2, and 4S) and high TrkA expression. In this study, we showed that EFNB2 and TrkA expressions were associated with both tumor stage and age, whereas EPHB6 and EFNB3 expressions were solely associated with tumor stage, suggesting that these genes were expressed in distinct subsets of NB. Kaplan-Meier and Cox regression analyses revealed that high-level expression of EPHB6, EFNB2, and EFNB3 predicted favorable NB outcome (P < 0.005), and their expression combined with TrkA expression predicted the disease outcome more accurately than each variable alone (P < 0.00005). Interestingly, if any one of the four genes (EPHB6, EFNB2, EFNB3, or TrkA) was expressed at high levels in NB, the patient survival was excellent (>90%). To address whether a good disease outcome of NB was a consequence of high-level expression of a “favorable NB gene,” we examined the effect of EPHB6 on NB cell lines. Transfection of EPHB6 cDNA into IMR5 and SY5Y expressing little endogenous EPHB6 resulted in inhibition of their clonogenicity in culture. Furthermore, transfection of EPHB6 suppressed the tumorigenicity of SY5Y in a mouse xenograft model, demonstrating that high-level expressions of favorable NB genes, such as EPHB6, can in fact suppress malignant phenotype of unfavorable NB.

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Heterozygous reeler mice (HRM) haploinsufficient for reelin express ≈50% of the brain reelin content of wild-type mice, but are phenotypically different from both wild-type mice and homozygous reeler mice. They exhibit, (i) a down-regulation of glutamic acid decarboxylase 67 (GAD67)-positive neurons in some but not every cortical layer of frontoparietal cortex (FPC), (ii) an increase of neuronal packing density and a decrease of cortical thickness because of neuropil hypoplasia, (iii) a decrease of dendritic spine expression density on basal and apical dendritic branches of motor FPC layer III pyramidal neurons, and (iv) a similar decrease in dendritic spines expressed on the basal dendrite branches of CA1 pyramidal neurons of the hippocampus. To establish whether the defect of GAD67 down-regulation observed in HRM is responsible for neuropil hypoplasia and decreased dendritic spine density, we studied heterozygous GAD67 knockout mice (HG67M). These mice exhibited a down-regulation of GAD67 mRNA expression in FPC (about 50%), but they expressed normal amounts of reelin and had no neuropil hypoplasia or down-regulation of dendritic spine expression. These findings, coupled with electron-microscopic observations that reelin colocalizes with integrin receptors on dendritic spines, suggest that reelin may be a factor in the dynamic expression of cortical dendritic spines perhaps by promoting integrin receptor clustering. These findings are interesting because the brain neurochemical and neuroanatomical phenotypic traits exhibited by the HRM are in several ways similar to those found in postmortem brains of psychotic patients.

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A promising class of compounds for DNA transfection have been designed by conjugating various polyamines to bile-acid-based amphiphiles. Formulations containing these compounds were tested for their ability to facilitate the uptake of a beta-galactosidase reporter plasmid into COS-7 cells. Dioleoyl phosphatidyl ethanolamine (DOPE) formulations of some of the compounds were several times better than Lipofectin at promoting DNA uptake. The most active compounds contained the most hydrophilic bile acid components. The activity is clearly not related to affinity for DNA: the hydrophobic bile acid conjugates were found to form stable complexes with DNA at lower charge ratios than the hydrophilic conjugates. We suggest that the high activity of the best compounds is related to their facial amphiphilicity, which may confer an ability to destabilize membranes. The success of these unusual cationic transfection agents may inspire the design of even more effective gene delivery agents.

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Este trabalho teve o propósito de avaliar a relação entre a cartilagem alar e a abertura piriforme a partir de imagens de tomografia computadorizada cone-beam e a relação do nariz com o padrão esquelético vertical da face. A pesquisa foi realizada com 96 imagens de indivíduos de ambos os sexos (49 masculino e 47 feminino), com idades entre 18 e 65 anos classificados de acordo com sua tipologia facial. Para a realização das marcações e mensurações de interesse foi utilizado o software OsiriX. A tipologia facial foi acessada através de três metodologias: índice facial, ângulo goníaco e proporção entre as alturas faciais. No corte axial da imagem de tomografia computadorizada, foram aferidas quatro grandezas lineares: largura do nariz externo, distância entre as inserções alares, extensão da base da abertura piriforme e máxima largura da abertura piriforme. Todas as grandezas foram mensuradas por dois examinadores em concordância. A análise dos resultados obtidos mostrou que há correlação entre as larguras do nariz externo e da abertura piriforme e entre a base da cavidade nasal e a distância entre as inserções alares. A largura da abertura piriforme aumenta proporcionalmente mais que a do nariz. Além disso, a tipologia facial longa associa-se à largura nasal.

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As Ciências Forenses empregam a técnica de Reconstrução Facial buscando aumentar as possibilidades de reconhecimento humano. Após análise antropológica, a face é esculpida sobre o crânio esqueletizado e divulgada na mídia. Existem várias metodologias para a modelagem do rosto e das características da face, bem como vários dados de espessuras de tecidos moles que auxiliam no contorno facial. Com o intuito de investigar se existe uma metodologia que favoreça mais reconhecimentos e que permita uma maior semelhança com o indivíduo, este trabalho buscou comparar reconstruções faciais manuais feitas com duas abordagens para o preenchimento dos tecidos moles (métodos Americano e de Manchester) e para a predição dos olhos, nariz, boca e orelhas. Também buscou comparar reconstruções realizadas com quatro tabelas de espessuras de tecidos moles, desenvolvidas para brasileiros por estudos prévios, observando a possibilidade de unir esses dados para auxiliar na reconstrução. Um quarto objetivo foi averiguar se existe influência do sexo e do conhecimento anatômico ou forense na frequência de reconhecimentos. O estudo foi dividido em duas fases. Na primeira, duas reconstruções foram realizadas para dois indivíduos alvos (um homem e uma mulher) com os métodos Americano e de Manchester, aplicando dois guias para olhos, nariz, boca e orelhas. As reconstruções foram avaliadas por quarenta indivíduos (homens e mulheres, divididos em 4 grupos - alunos de graduação em Odontologia que não passaram pela disciplina de Odontologia Legal, alunos de graduação em Odontologia que passaram pela disciplina, especialistas em Odontologia Legal e indivíduos que não possuíam conhecimento de anatomia humana) por meio dos testes de reconhecimento e semelhança. Para o alvo feminino, as frequências de reconhecimentos foram 20% e 10% para os métodos Americano e de Manchester, respectivamente; para o alvo masculino, as frequências foram 35% e 17,5%. Em relação à semelhança, as medianas foram menores que 3 (em uma escala de 1 a 5); entretanto, foi verificada uma exceção para a escultura feita com o método Americano para o alvo masculino, a qual apresentou mediana 3. Na segunda fase, reconstruções faciais para quatro alvos (dois homens e duas mulheres) foram obtidas com o método Americano, considerando as quatro tabelas de espessuras de tecidos moles para brasileiros. Dezesseis reconstruções foram avaliadas por cento e vinte indivíduos, também pelos testes de reconhecimento e semelhança. Assim como na fase I, foram considerados o sexo e o grupo dos avaliadores. Para o alvo 1, as proporções de acertos são significativamente maiores para reconstruções feitas com as tabelas de cadáveres (44% e 38%) em relação às com os dados de exames de imagem. Para o alvo 4, as proporções de acertos com os dados de cadáveres (Tedeschi-Oliveira et al.) e com os de ressonância magnética foram significativamente maiores comparados às reconstruções com dados de tomografias computadorizadas. Em relação à semelhança, somente o alvo 1 mostrou diferenças significativas de frequências de semelhança leve entre reconstruções. Além disso, não houve influência nem do sexo, nem do conhecimento de anatomia nas frequências de reconhecimentos corretos. Espera-se que a tabela proposta possa ser empregada para a população brasileira.

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Historians have yet to realize the depth of artist Janet Sobel’s artistic aptitude and ingenuity. This paper focuses on understanding how unique Sobel and her art were due to her distinctive world experiences and her ability to express her feelings about these experiences through her art. It also demonstrates the importance of her Jewish and Ukrainian heritage, showing how this influenced her artistic development. Sobel immigrated to the United States at a young age and struggled with her identity. Her art was a way for her to define and accept her personal identity as an immigrant Eastern European Jew in America. In addition to this heritage, Sobel experienced many traumatic events in her early life. Her art therefore served as a way for Sobel to work through this past trauma and come to terms with it.

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Exercises of application of the systematic procedure to derive linear inequalities for logic expressions (Ejercicios de aplicación del método sistemático de obtención de restricciones lineales para expresiones lógicas).

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This paper shows a system about the recognition of temporal expressions in Spanish and the resolution of their temporal reference. For the identification and recognition of temporal expressions we have based on a temporal expression grammar and for the resolution on an inference engine, where we have the information necessary to do the date operation based on the recognized expressions. For further information treatment, the output is proposed by means of XML tags in order to add standard information of the resolution obtained. Different kinds of annotation of temporal expressions are explained in another articles [WILSON2001][KATZ2001]. In the evaluation of our proposal we have obtained successful results.

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This paper tells about the recognition of temporal expressions and the resolution of their temporal reference. A proposal of the units we have used to face up this tasks over a restricted domain is shown. We work with newspapers' articles in Spanish, that is why every reference we use is in Spanish. For the identification and recognition of temporal expressions we base on a temporal expression grammar and for the resolution on a dictionary, where we have the information necessary to do the date operation based on the recognized expressions. In the evaluation of our proposal we have obtained successful results for the examples studied.

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This paper addresses the problem of the automatic recognition and classification of temporal expressions and events in human language. Efficacy in these tasks is crucial if the broader task of temporal information processing is to be successfully performed. We analyze whether the application of semantic knowledge to these tasks improves the performance of current approaches. We therefore present and evaluate a data-driven approach as part of a system: TIPSem. Our approach uses lexical semantics and semantic roles as additional information to extend classical approaches which are principally based on morphosyntax. The results obtained for English show that semantic knowledge aids in temporal expression and event recognition, achieving an error reduction of 59% and 21%, while in classification the contribution is limited. From the analysis of the results it may be concluded that the application of semantic knowledge leads to more general models and aids in the recognition of temporal entities that are ambiguous at shallower language analysis levels. We also discovered that lexical semantics and semantic roles have complementary advantages, and that it is useful to combine them. Finally, we carried out the same analysis for Spanish. The results obtained show comparable advantages. This supports the hypothesis that applying the proposed semantic knowledge may be useful for different languages.

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In the past years, an important volume of research in Natural Language Processing has concentrated on the development of automatic systems to deal with affect in text. The different approaches considered dealt mostly with explicit expressions of emotion, at word level. Nevertheless, expressions of emotion are often implicit, inferrable from situations that have an affective meaning. Dealing with this phenomenon requires automatic systems to have “knowledge” on the situation, and the concepts it describes and their interaction, to be able to “judge” it, in the same manner as a person would. This necessity motivated us to develop the EmotiNet knowledge base — a resource for the detection of emotion from text based on commonsense knowledge on concepts, their interaction and their affective consequence. In this article, we briefly present the process undergone to build EmotiNet and subsequently propose methods to extend the knowledge it contains. We further on analyse the performance of implicit affect detection using this resource. We compare the results obtained with EmotiNet to the use of alternative methods for affect detection. Following the evaluations, we conclude that the structure and content of EmotiNet are appropriate to address the automatic treatment of implicitly expressed affect, that the knowledge it contains can be easily extended and that overall, methods employing EmotiNet obtain better results than traditional emotion detection approaches.

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Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz