925 resultados para Face recognition


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There is evidence for the late development in humans of configural face and animal recognition. We show that the recognition of artificial three-dimensional (3D) objects from part configurations develops similarly late. We also demonstrate that the cross-modal integration of object information reinforces the development of configural recognition more than the intra-modal integration does. Multimodal object representations in the brain may therefore play a role in configural object recognition. © 2003 Elsevier B.V. All rights reserved.

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Four experiments with unfamiliar objects examined the remarkably late consolidation of part-relational relative to part-based object recognition (Jüttner, Wakui, Petters, Kaur, & Davidoff, 2013). Our results indicate a particularly protracted developmental trajectory for the processing of metric part relations. Schoolchildren aged 7 to 14 years and adults were tested in 3-Alternative-Forced-Choice tasks to judge the correct appearance of upright and inverted newly learned multipart objects that had been manipulated in terms of individual parts or part relations. Experiment 1 showed that even the youngest tested children were close to adult levels of performance for recognizing categorical changes of individual parts and relative part position. By contrast, Experiment 2 demonstrated that performance for detecting metric changes of relative part position was distinctly reduced in young children compared with recognizing metric changes of individual parts, and did not approach the latter until 11 to 12 years. A similar developmental dissociation was observed in Experiment 3, which contrasted the detection of metric relative-size changes and metric part changes. Experiment 4 showed that manipulations of metric size that were perceived as part (rather than part-relational) changes eliminated this dissociation. Implications for theories of object recognition and similarities to the development of face perception are discussed. © 2014 American Psychological Association.

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Objectives: The aims were to determine if emotion recognition deficits observed in eating disorders generalise to non-clinical disordered eating and to establish if other psychopathological and personality factors contributed to, or accounted for, these deficits. Design: Females with high (n=23) and low (n=22) scores on the Eating Disorder Inventory (EDI) were assessed on their ability to recognise emotion from videotaped social interactions. Participants also completed a face memory task, a Stroop task, and self-report measures of alexithymia, depression and anxiety. Results: Relative to the low EDI group, high EDI participants exhibited a general deficit in recognition of emotion, which was related to their scores on the alexithymia measure and the bulimia subscale of the EDI. They also exhibited a specific deficit in the recognition of anger, which was related to their scores on the body dissatisfaction subscale of the EDI. Conclusions: In line with clinical eating disorders, non-clinical disordered eating is associated with emotion recognition deficits. However, the nature of these deficits appears to be dependent upon the type of eating psychopathology and the degree of co-morbid alexithymia.

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Emotion-based analysis has raised a lot of interest, particularly in areas such as forensics, medicine, music, psychology, and human-machine interface. Following this trend, the use of facial analysis (either automatic or human-based) is the most common subject to be investigated once this type of data can easily be collected and is well accepted in the literature as a metric for inference of emotional states. Despite this popularity, due to several constraints found in real world scenarios (e.g. lightning, complex backgrounds, facial hair and so on), automatically obtaining affective information from face accurately is a very challenging accomplishment. This work presents a framework which aims to analyse emotional experiences through naturally generated facial expressions. Our main contribution is a new 4-dimensional model to describe emotional experiences in terms of appraisal, facial expressions, mood, and subjective experiences. In addition, we present an experiment using a new protocol proposed to obtain spontaneous emotional reactions. The results have suggested that the initial emotional state described by the participants of the experiment was different from that described after the exposure to the eliciting stimulus, thus showing that the used stimuli were capable of inducing the expected emotional states in most individuals. Moreover, our results pointed out that spontaneous facial reactions to emotions are very different from those in prototypic expressions due to the lack of expressiveness in the latter.

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[EN]This paper describes in detail a real-time multiple face detection system for video streams. The system adds to the good performance provided by a window shift approach, the combination of different cues available in video streams due to temporal coherence. The results achieved by this combined solution outperform the basic face detector obtaining a 98% success rate for around 27000 images, providing additionally eye detection and a relation between the successive detections in time by means of detection threads.

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Ao pensar na morte há um reconhecimento da vulnerabilidade humana e da própria fragilidade da vida. A morte é universal, mas experienciada de uma forma individualizada por cada um de nós, a partir da personalidade, experiências de vida, variáveis pessoais, idade, sexo, religião. Vivenciar a morte e o morrer poderá conduzir a sensações de medo e ansiedade. Os agentes funerários que lidam diariamente com a morte e com o “luto” (do corpo morto e dos familiares em relação ao ente querido que perderam) poderão estar expostos a sentimentos de ansiedade depressiva pela ativação diária do confronto com a própria morte, ou com a morte de pessoas a quem estão intimamente ligados. É objetivo deste estudo avaliar os níveis de ansiedade em face da morte em agentes funerários, e ainda explorar a eventual associação entre fatores sociodemográficos e profissionais selecionados e esta variável. A amostra é composta por 60 sujeitos de uma empresa funerária em Portugal. Os instrumentos psicométricos utilizados foram a Escala de Ansiedade face à Morte (DAQ), e um questionário sociodemográfico desenhado para o presente estudo. Os resultados globais mostram que os Agentes Funerários apresentam níveis de ansiedade face à morte estatisticamente significativos (M = 35,88; DP = 9,02). O género, a idade, religião, anos de experiência, estado civil, terem filhos, ter morrido alguém próximo ou significativo, especificidade de trabalho: ser comercial ou operacional o número de contatos, não marcam significativamente a forma como os sujeitos em estudo percecionam a sua ansiedade em face da morte. Os níveis de ansiedade aumentam entre aqueles que não tiveram formação específica para lidar com estas situações. / When thinking about death there is recognition of human vulnerability and fragility of life itself. Death is universal but experienced individually by each of us, through personality, life experiences, personal variables, age, sex, religion. Experiencing death and dying can lead to feelings of fear and anxiety. Funeral Agents who daily deal with death and with the "mourning" (the dead body and the family of the deceased) may be exposed to feelings of depressive anxiety activated by the daily confrontation with death itself or death of people who are close to them. The aim of this study is to assess the levels of anxiety in Funeral Agents when facing death, and also explore the eventual association of social-demographic and professional factors with this variable. The sample consisted of 60 subjects of a Portuguese Funeral company. The instruments used were the Death Anxiety Questionnaire (DAQ) and a socialdemographic questionnaire designed for the present study. The overall results show that Funeral Agents present anxiety levels statistically significant when facing death (M = 35.88, SD = 9.02). Gender, age, religion, years of experience, marital status, having children, the death of someone close or important, and the specificity of the job (commercial or operational agent), the number of contacts, show no statistically significant association with anxiety when facing death. However, the levels of anxiety increase among those who had had no specific formation to deal with these situations.

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Com a realização deste estudo pretendeu-se cumprir dois objetivos: i) aferir a eficácia do patrocínio desportivo através da utilização de medidas como a notoriedade da marca, a atitude face ao patrocinador e a intenção de compra dos espectadores presentes no circuito nacional de surf (Liga Moche); ii) analisar a forma como o envolvimento das pessoas com o surf pode ter influência na eficácia do patrocínio. Para cumprir estes objetivos foram aplicados 250 questionários a espectadores presentes nas provas do circuito nacional de surf. Os dados foram analisados através de estatística descritiva, testes de correlação de Pearson e de tstudent. Os resultados indicam que a marca patrocinadora do evento de surf, a Moche, apresenta elevados níveis de notoriedade espontânea (83,2%) e assistida (91,2%) entre os espectadores do circuito nacional e que os espectadores apresentam também atitudes favoráveis assim como intenções de compra favoráveis. Verificou-se também uma correlação significativamente positiva entre a atitude face ao patrocinador e as intenções de compra. Por último, os praticantes de surf e os espectadores dos eventos apresentam uma atitude mais favorável e maiores intenções de compra dos produtos patrocinadores do que os que não praticam surf nem costumam assistir a eventos de surf. Estes resultados devem ser levados em consideração pelos responsáveis de futuros eventos de surf.

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In the past few years, human facial age estimation has drawn a lot of attention in the computer vision and pattern recognition communities because of its important applications in age-based image retrieval, security control and surveillance, biomet- rics, human-computer interaction (HCI) and social robotics. In connection with these investigations, estimating the age of a person from the numerical analysis of his/her face image is a relatively new topic. Also, in problems such as Image Classification the Deep Neural Networks have given the best results in some areas including age estimation. In this work we use three hand-crafted features as well as five deep features that can be obtained from pre-trained deep convolutional neural networks. We do a comparative study of the obtained age estimation results with these features.

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In the Amazon Region, there is a virtual absence of severe malaria and few fatal cases of naturally occurring Plasmodium falciparum infections; this presents an intriguing and underexplored area of research. In addition to the rapid access of infected persons to effective treatment, one cause of this phenomenon might be the recognition of cytoadherent variant proteins on the infected red blood cell (IRBC) surface, including the var gene encoded P. falciparum erythrocyte membrane protein 1. In order to establish a link between cytoadherence, IRBC surface antibody recognition and the presence or absence of malaria symptoms, we phenotype-selected four Amazonian P. falciparum isolates and the laboratory strain 3D7 for their cytoadherence to CD36 and ICAM1 expressed on CHO cells. We then mapped the dominantly expressed var transcripts and tested whether antibodies from symptomatic or asymptomatic infections showed a differential recognition of the IRBC surface. As controls, the 3D7 lineages expressing severe disease-associated phenotypes were used. We showed that there was no profound difference between the frequency and intensity of antibody recognition of the IRBC-exposed P. falciparum proteins in symptomatic vs. asymptomatic infections. The 3D7 lineages, which expressed severe malaria-associated phenotypes, were strongly recognised by most, but not all plasmas, meaning that the recognition of these phenotypes is frequent in asymptomatic carriers, but is not necessarily a prerequisite to staying free of symptoms.

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OBJETIVO: o objetivo deste trabalho foi classificar e determinar a prevalência dos indivíduos portadores de comprometimento vertical nas relações faciais, conforme a severidade da discrepância e, especialmente, dos portadores de Padrão Face Longa. MÉTODOS: a amostra constou de 5.020 sujeitos de nacionalidade brasileira, de ambos os sexos, com idades entre 10 anos e 16 anos e 11 meses, matriculados no Ensino Fundamental do município de Bauru-SP. O exame da morfologia facial constou da observação direta da face, em normas frontal e lateral, sempre com os lábios em repouso, buscando identificar aqueles indivíduos que apresentassem comprometimento vertical nas relações faciais. Esses, uma vez identificados, foram classificados, considerando-se a severidade, em três subtipos: moderado, médio e grave. Para fins de determinação da prevalência dos portadores de Padrão Face Longa, apenas os classificados como dos subtipos médio e grave foram considerados. RESULTADOS: observou-se uma prevalência de 34,94% de comprometimento vertical nas relações faciais e 14,06% de Padrão Face Longa. CONCLUSÃO: os resultados obtidos no presente estudo permitiram concluir que a prevalência do comprometimento vertical nas relações faciais e do Padrão Face Longa foi maior do que a presumida com base na literatura.

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OBJETIVO: definir valores cefalométricos esqueléticos e dentários para adolescentes brasileiros com Padrão Face Longa. MÉTODOS: a amostra foi constituída de telerradiografias em norma lateral de 30 pacientes com Face Longa, sendo 17 do sexo feminino e 13 do masculino; e 30 pacientes face Padrão I, 15 do sexo masculino e 15 do feminino, no estágio de dentadura permanente durante a adolescência. As características do Padrão Face Longa foram definidas clinicamente, pela análise facial. As seguintes grandezas cefalométricas foram avaliadas: (1) Comportamento sagital das bases apicais (SNA, SNB, ANB, NAP, Co-A, Co-Gn); (2) Comportamento vertical das bases apicais (SN.PP, SN.PM, ângulo goníaco, AFAT, AFAI, AFAM, AFP, AFATperp, AFAIperp); (3) Comportamento dentoalveolar (1-PP, 6-PP, 1-PM, 6-PM, 1.PP, IMPA); e (4) Proporção entre as alturas faciais (AFAIPerp/AFATPerp, AFAI/AFAT, AFAM/AFAI). RESULTADOS E CONCLUSÕES: o erro vertical na Face Longa concentra-se no terço inferior. A maxila apresenta uma maior altura dentoalveolar e a mandíbula, com morfologia mais vertical, mostra maior rotação no sentido horário. Essas características morfológicas e espaciais acarretam alterações sagitais e verticais no esqueleto e alterações verticais dentoalveolares. No sentido sagital, os ângulos de convexidade facial estão aumentados. No sentido vertical, as alturas faciais anteriores total e inferior estão aumentadas. O componente dentoalveolar está mais longo.

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A modified version of the intruder-resident paradigm was used to investigate if social recognition memory lasts at least 24 h. One hundred and forty-six adult male Wistar rats were used. Independent groups of rats were exposed to an intruder for 0.083, 0.5, 2, 24, or 168 h and tested 24 h after the first encounter with the familiar or a different conspecific. Factor analysis was employed to identify associations between behaviors and treatments. Resident rats exhibited a 24-h social recognition memory, as indicated by a 3- to 5-fold decrease in social behaviors in the second encounter with the same conspecific compared to those observed for a different conspecific, when the duration of the first encounter was 2 h or longer. It was possible to distinguish between two different categories of social behaviors and their expression depended on the duration of the first encounter. Sniffing the anogenital area (49.9% of the social behaviors), sniffing the body (17.9%), sniffing the head (3%), and following the conspecific (3.1%), exhibited mostly by resident rats, characterized social investigation and revealed long-term social recognition memory. However, dominance (23.8%) and mild aggression (2.3%), exhibited by both resident and intruders, characterized social agonistic behaviors and were not affected by memory. Differently, sniffing the environment (76.8% of the non-social behaviors) and rearing (14.3%), both exhibited mostly by adult intruder rats, characterized non-social behaviors. Together, these results show that social recognition memory in rats may last at least 24 h after a 2-h or longer exposure to the conspecific.

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The Anopheles (Nyssorhynchus) albitarsis complex includes six species: An. albitarsis, Anopheles oryzalymnetes Wilkerson and Motoki, n. sp., Anopheles marajoara, Anopheles dencorum, Anopheles janconnae Wilkerson and Sallum, n. sp., and An. albitarsis F. Except for An. deancorum, species of the complex are indistinguishable when only using morphology. The problematic distinction among species of the complex has made study of malaria transmission and ecology of An. albitarsis s.l. difficult. Consequently, involvement of species of the An. albitarsis complex in human Plasmodium transmission is not clear throughout its distribution range. With the aim of clarifying the taxonomy of the above species, with the exception of An. albitarsis F, we present comparative morphological and morphometric analyses, morphological redescriptions of three species and descriptions of two new species using individuals from populations in Brazil, Paraguay, Argentina and Venezuela. The study included characters from adult females, males, fourth-instar larvae, pupae and male genitalia of An. albitarsis, An. deaneorum and An. oryzalimnetes n. sp. For An. janconnae n. sp. only characters of the female, male and male genitalia were analysed. Fourth-instar larvae and pupae and male genitalia characteristics of all five species are illustrated. Bionomics and distribution data are given based on published literature records

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Background: A family of hydrophilic acylated surface (HASP) proteins, containing extensive and variant amino acid repeats, is expressed at the plasma membrane in infective extracellular (metacyclic) and intracellular (amastigote) stages of Old World Leishmania species. While HASPs are antigenic in the host and can induce protective immune responses, the biological functions of these Leishmania-specific proteins remain unresolved. Previous genome analysis has suggested that parasites of the sub-genus Leishmania (Viannia) have lost HASP genes from their genomes. Methods/Principal Findings: We have used molecular and cellular methods to analyse HASP expression in New World Leishmania mexicana complex species and show that, unlike in L. major, these proteins are expressed predominantly following differentiation into amastigotes within macrophages. Further genome analysis has revealed that the L. (Viannia) species, L. (V.) braziliensis, does express HASP-like proteins of low amino acid similarity but with similar biochemical characteristics, from genes present on a region of chromosome 23 that is syntenic with the HASP/SHERP locus in Old World Leishmania species and the L. (L.) mexicana complex. A related gene is also present in Leptomonas seymouri and this may represent the ancestral copy of these Leishmania-genus specific sequences. The L. braziliensis HASP-like proteins (named the orthologous (o) HASPs) are predominantly expressed on the plasma membrane in amastigotes and are recognised by immune sera taken from 4 out of 6 leishmaniasis patients tested in an endemic region of Brazil. Analysis of the repetitive domains of the oHASPs has shown considerable genetic variation in parasite isolates taken from the same patients, suggesting that antigenic change may play a role in immune recognition of this protein family. Conclusions/Significance: These findings confirm that antigenic hydrophilic acylated proteins are expressed from genes in the same chromosomal region in species across the genus Leishmania. These proteins are surface-exposed on amastigotes (although L. (L.) major parasites also express HASPB on the metacyclic plasma membrane). The central repetitive domains of the HASPs are highly variant in their amino acid sequences, both within and between species, consistent with a role in immune recognition in the host.

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Schistosomes are unable to synthesize purines de novo and depend exclusively on the salvage pathway for their purine requirements. It has been suggested that blockage of this pathway could lead to parasite death. The enzyme purine nucleoside phosphorylase (PNP) is one of its key components and molecules designed to inhibit the low-molecular-weight (LMW) PNPs, which include both the human and schistosome enzymes, are typically analogues of the natural substrates inosine and guanosine. Here, it is shown that adenosine both binds to Schistosoma mansoni PNP and behaves as a weak micromolar inhibitor of inosine phosphorolysis. Furthermore, the first crystal structures of complexes of an LMW PNP with adenosine and adenine are reported, together with those with inosine and hypoxanthine. These are used to propose a structural explanation for the selective binding of adenosine to some LMW PNPs but not to others. The results indicate that transition-state analogues based on adenosine or other 6-amino nucleosides should not be discounted as potential starting points for alternative inhibitors.