699 research outputs found

    Topography and instability of monolayers near domain boundaries

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    We theoretically study the topography of a biphasic surfactant monolayer in the vicinity of domain boundaries. The differing elastic properties of the two phases generally lead to a nonflat topography of ``mesas'', where domains of one phase are elevated with respect to the other phase. The mesas are steep but low, having heights of up to 10 nm. As the monolayer is laterally compressed, the mesas develop overhangs and eventually become unstable at a surface tension of about K(dc)^2 (dc being the difference in spontaneous curvature and K a bending modulus). In addition, the boundary is found to undergo a topography-induced rippling instability upon compression, if its line tension is smaller than about K(dc). The effect of diffuse boundaries on these features and the topographic behavior near a critical point are also examined. We discuss the relevance of our findings to several experimental observations related to surfactant monolayers: (i) small topographic features recently found near domain boundaries; (ii) folding behavior observed in mixed phospholipid monolayers and model lung surfactants; (iii) roughening of domain boundaries seen under lateral compression; (iv) the absence of biphasic structures in tensionless surfactant films.Comment: 17 pages, 9 figures, using RevTeX and epsf, submitted to Phys Rev

    Preferential attentional engagement drives attentional bias to snakes in Japanese macaques (Macaca fuscata) and humans (Homo sapiens)

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    © 2018, The Author(s). In humans, attentional biases have been shown to negative (dangerous animals, physical threat) and positive (high caloric food, alcohol) stimuli. However, it is not clear whether these attentional biases reflect on stimulus driven, bottom up, or goal driven, top down, attentional processes. Here we show that, like humans, Japanese macaques show an attentional bias to snakes in a dot probe task (Experiment 1). Moreover, this attentional bias reflects on bottom up driven, preferential engagement of attention by snake images (Experiment 2a), a finding that was replicated in a study that used the same methodology in humans (Experiment 2b). These results are consistent with the notion that attentional bias to snakes reflects on an evolutionarily old, stimulus driven threat detection mechanism which is found in both species

    Ansiedade dos estudantes diante da expectativa do exame vestibular

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    Este estudio investigó la ansiedad de los estudiantes en las escuelas privadas en un estado de Brasil en el examen de ingreso. La muestra fuese compuesta de 124 estudiantes de la escuela secundaria participantes del PISM (Proceso de Admisión Común), siendo 66 mujeres e 58 hombres, 69 alumnos del 1er año de escuela secundaria y 55 del 3er año. Los estudiantes respondieron a un cuestionario socio-demográfico y al Inventario de Ansiedad Rasgo-Estado (IDATE), en sus propias aulas. Hubo una diferencia significativa en relación con el género (p=0,036) que se encontró un mayor nivel de ansiedad estado en el 1er año de las mujeres en comparación con los hombres del 1er año (p = 0,004). El mismo resultado se encontró con respecto a la ansiedad-rasgo: las mujeres de 1er año son más ansiosas que los hombres del 1er año (p=0,000).O presente estudo investigou a ansiedade dos jovens estudantes de escolas particulares de um estado do Brasil em relação ao exame vestibular. A amostra foi composta por 124 estudantes do ensino médio participantes do vestibular seriado PISM (Processo de Ingresso Seletivo Misto), sendo 66 do gênero feminino e 58 do gênero masculino, 69 alunos do 1º ano do ensino médio e 55 do 3º ano. Os estudantes responderam a um questionário sócio-demográfico e ao Inventário de Ansiedade Traço-Estado (IDATE) na suas próprias salas de aula. Foi observada uma diferença significativa quanto ao gênero (p=0,036) sendo que foi encontrado um maior nível de ansiedade-estado nas mulheres do 1º ano comparativamente aos rapazes do 1ºano (p=0,004). O mesmo resultado foi encontrado com relação à ansiedade-traço: moças do 1º ano são mais ansiosas do que rapazes do 1º ano (p=0,000).This study investigated the anxiety of private schools students at the expectation of attending colleges' entrance examination in one Brazilian state. The sample consisted of 124 high school students participating in the PISM series of examination (Joint Selective Admission Process). They were 66 females and 58 males, 69 students from the 1st year and 55 from the 3rd year. Students answered a sociodemographic questionnaire and the State-Trait Anxiety Inventory in their respective classrooms. A significant difference regarding gender (p=0.036) was found, women from the 1st year presented higher levels of state-anxiety compared to men from the 1st year (p=0.004). The same result was found with respect to the trait-anxiety, women from the 1st year were more anxious than men from the 1st year (p=0.000)

    Investigation of attentional bias in obsessive compulsive disorder with and without depression in visual search

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    Copyright: © 2013 Morein-Zamir et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedWhether Obsessive Compulsive Disorder (OCD) is associated with an increased attentional bias to emotive stimuli remains controversial. Additionally, it is unclear whether comorbid depression modulates abnormal emotional processing in OCD. This study examined attentional bias to OC-relevant scenes using a visual search task. Controls, non-depressed and depressed OCD patients searched for their personally selected positive images amongst their negative distractors, and vice versa. Whilst the OCD groups were slower than healthy individuals in rating the images, there were no group differences in the magnitude of negative bias to concern-related scenes. A second experiment employing a common set of images replicated the results on an additional sample of OCD patients. Although there was a larger bias to negative OC-related images without pre-exposure overall, no group differences in attentional bias were observed. However, OCD patients subsequently rated the images more slowly and more negatively, again suggesting post-attentional processing abnormalities. The results argue against a robust attentional bias in OCD patients, regardless of their depression status and speak to generalized difficulties disengaging from negative valence stimuli. Rather, post-attentional processing abnormalities may account for differences in emotional processing in OCD.Peer reviewedFinal Published versio

    Psoríase e o impacto na sexualidade

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    Psoriasis is a skin disease, not contagious, chronic, serious and considered limiting, resulting prejudice, stigma and social exclusion providing loss in quality of life.Mostly affects self-image of affected people, as well as self-esteem and self-concept.These disease characteristics bring great losses in occupational areas, damaging interpersonal relationships of individuals, which may cause impact on various occupational areas, including sexuality, which translates not only as sex itself, but also as identity, social roles, pleasure, reproduction and other. The aim of this study was to investigate the self-image of individuals with psoriasis and their influence on sexuality. This is a qualitative study of a case study with seven patients in the Reference Center, Support and Treatment Paraíba State Psoriasis installed in the clinic of the University Hospital LauroWanderley – Universidade Federal da Paraíba. Data were collected through semi-structured interview, categorized and treated according to the Content Analysis. The results show that psoriasis affects the sexuality of individuals, more significantly in women's fashion, as attribute different meanings to the body, for reasons of aesthetics and beauty.Men also feel affected, but in view of the achievement, caring companionship, and seek to clarify their partners or future partners and their relationships, about the disease. We note here the influence of culture to gender conditions.A Psoríase é uma doença dermatológica, não contagiosa, crônica, considerada grave e limitante, acarretando preconceito, estigma e exclusão social proporcionando prejuízos na qualidade de vida. Na sua grande maioria, afeta a autoimagem das pessoas acometidas, assim como a autoestima e autoconceito. Estas características da doença trazem grandes prejuízos nas áreas ocupacionais, prejudicando as relações interpessoais dos indivíduos, podendo ocasionar impacto em várias áreas ocupacionais, incluindo a sexualidade, que se traduz não só como o sexo em si, mas também como identidade, papéis sociais, prazer, reprodução entre outros. O objetivo deste estudo foi investigar sobre a autoimagem dos indivíduos com psoríase e sua influência na sexualidade. Trata-se de um estudo qualitativo do tipo estudo de caso, com sete pacientes do Centro de Referência, Apoio e Tratamento em Psoríase do Estado da Paraíba instalado no ambulatório do Hospital Universitário Lauro Wanderley – Universidade Federal da Paraíba. Os dados foram coletados por meio de entrevista semiestruturada, categorizados e tratados de acordo com a Análise de Conteúdo. Os resultados encontrados mostram que a psoríase afeta a sexualidade dos indivíduos, de forma mais significativa nas mulheres, pois atribuem significados diferentes ao corpo, por razões de estética e beleza. Os homens também se sentem afetados, mas na perspectiva da conquista, se importando com o companheirismo, e procuram esclarecer para suas companheiras ou futuras companheiras e em seus relacionamentos, sobre a doença. Observamos aqui a influência da cultura às condições de gêner
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