Braid groups in complex Grassmannians

We describe the fundamental group and second homotopy group of ordered $k-$point sets in $Gr(k,n)$ generating a subspace of fixed dimension.Comment: 10 page

Regularity of mean curvature flow of graphs on Lie groups free up to step 2

We consider (smooth) solutions of the mean curvature flow of graphs over bounded domains in a Lie group free up to step two (and not necessarily nilpotent), endowed with a one parameter family of Riemannian metrics \sigma_\e collapsing to a subRiemannian metric $\sigma_0$ as \e\to 0. We establish $C^{k,\alpha}$ estimates for this flow, that are uniform as \e\to 0 and as a consequence prove long time existence for the subRiemannian mean curvature flow of the graph. Our proof extend to the setting of every step two Carnot group (not necessarily free) and can be adapted following our previous work in \cite{CCM3} to the total variation flow.Comment: arXiv admin note: text overlap with arXiv:1212.666

Braid groups in complex spaces

We describe the fundamental groups of ordered and unordered $k-$point sets in the n-dimensional complex space $C^n$ generating an affine subspace of fixed dimension

Health and socio-demographic conditions as determinants of marriage and social mobility

This paper makes use of data collected from military registers and marriage certificates for the population of Alghero, in Sardinia, for the period 1866-1925, with the aim of investigating the role played by physical characteristics and health in the possibility of social mobility through marriage. Our findings demonstrate that, whereas physical defects and ill health had little impact on the chances of marrying an illiterate woman, these factors did have a negative effect on the chances of marrying a woman who was literate. In a context in which intergenerational social mobility remained limited and the family had the final say on marriage arrangements, it is likely that only healthy individuals were selected for marriages regarded as strategic for the purposes of forming and strengthening family alliances, and/or improving the social position within the community.health, marriage, Sardinia, social mobility

Chisini's conjecture for curves with singularities of type xn=ymx^n=y^m

This paper is devoted to a very classical problem that can be summarized as follows: let S be a non singular compact complex surface, f:S --> P^2 a finite morphism having simple branching, B the branch curve: to what extent does B determine f? The problem was first studied by Chisini who proved that B determines S and f, assuming B to have only nodes and cusps as singularities, the degree d of f to be greater than 5, and a very strong hypothesis on the possible degenerations of B, and posed the question if the first or the third hypothesis could be weakened. Recently Kulikov and Nemirovski proved the result for d >= 12, and B having only nodes and cusps as singularities. In this paper we weaken the hypothesis about the singularities of B: we generalize the theorem of Kulikov and Nemirovski for B having only singularities of type {x^n=y^m}, in the additional hypothesis of smoothness for the ramification divisor. Moreover we exhibit a family of counterexamples showing that our additional hypothesis is necessary.Comment: 27 pages, LaTeX, 1 figure (file=polypicc.eps

The influence of affective factors on time perception

Several studies have suggested that both affective valence and arousal affect the perception of time. How-ever, in previous experiments these two affective dimensions were not systematically controlled. In the present study, a set of emotional slides rated for valence and arousal (International Affective Picture System) were projected to two groups of subjects for 2, 4 and 6 sec. One group estimated the duration on an analog scale and a second group reproduced the interval by pushing a button. Heart rate and skin conductance responses were also recorded. A highly significant valence by arousal interaction affected duration judg-ments. For low arousal stimuli, the duration of negative slides was judged relatively shorter than the duration of positive slides. For high arousal stimuli, the duration of negative slides was judged longer than the dura-tion of positive slides. These results are interpreted within a model of action tendency, in which the level of arousal controls two different motivational mechanisms, one emotional and the other attentional

Características sociodemográficas e de personalidade de adolescentes em processo de orientação profissional: a técnica de Zulliger como instrumento de análise

The professional choice usually occurs in adolescence, a phase that for most young people is fraught with internal and external conflicts. Vocational guidance (VG) helps young people to reflect on their characteristics, interests, labor market, meaning of work in their lifes, encouraging self-knowledge so they can make a safer choice. This research aimed to provide information on sociodemographic and personality characteristics of adolescents in VG process, characterizing the profile of the sample and addressing decision-making as an outcome of choice. In addition, we analyzed the results of psychometric and projective instruments in the identification of personality characteristics, and investigated the possible influence of symptoms of depression and anxiety in vocational indecision. The first section consisted of a systematic literature review, in order to create a mapping in databases of scientific journals on studies describing the use of psychological tests for the analysis of personality in vocational guidance. The databases that were used for the search were Medline, PsyicINFO, Lilacs and ProQuest, which were researched the literature production from 2005 to 2011 using the keywords "psychological tests" and "vocational guidance";"occupational choice" and "personality traits" and "psychological assessment","vocational guidance" and "personality". It was found that few articles have been published addressing the objective of this review, however, the subject of vocational guidance is widespread in many countries, existing extensive research and publications in the area. The three empirical studies that support the thesis took place from the use of sociodemographic data sheet, Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI-II), Factorial Personality Inventory (IFP), Questionnaire to Evaluate Typology (QUATI), Readiness Ruler and Zulliger test. The studies used the quantitative and transversal method, with the sample for convenience. In total we analyzed data from 100 adolescents, aged 15 to 26 years, who sought vocational guidance of the SAPP-PUCRS. The second section aimed to analyze the sociodemographic and personality characteristics of adolescents; the third focused on the process of decision making and the predominant characteristics, and the fourth assessed the possible influence of symptoms of anxiety and depression in decision making. It was found through studies that some personality characteristics are consistent with the phase in which young people are, and we observed a tendency towards extroversion, the appreciation for movement and constant change, the use of feelings when making decisions and solving problems, the presence of limited resources to direct and organize behavior, showing some impulsivity in certain situations. We identified the readiness for change in a process of vocational guidance and a predominance of the introversion vivencial style in decision making. The study also found that the majority of the population studied obtained minimum and light levels on testing involving the BAI and BDI-II, indicating expected symptoms for a young and non-clinical population, with no significant influence of anxiety and depression symptoms in their professional choice.A escolha profissional geralmente ocorre na adolescência, fase que para a maioria dos jovens é permeada de conflitos internos e externos. A orientação profissional (OP) auxilia os jovens para que possam refletir sobre suas características, interesses, mercado de trabalho, significado do trabalho na sua vida, estimulando o autoconhecimento para que possam tomar uma decisão mais segura. Esta pesquisa objetivou informar sobre as características sociodemográficas e de personalidade de adolescentes em processo de OP, caracterizando o perfil da amostra estudada e abordando a tomada de decisão como desfecho da escolha. Além disso, foram analisados os resultados de instrumentos projetivos e psicométricos na identificação de características de personalidade e, investigou-se a possível influência de sintomas de depressão e de ansiedade na indecisão profissional. A primeira seção constituiu-se de uma revisão sistemática da literatura, com o objetivo de realizar um mapeamento, em bases de dados de periódicos científicos, sobre estudos que descrevessem a utilização de testes psicológicos para a análise de personalidade em orientação profissional. As bases de dados que serviram de busca de artigos foram a MedLine, PsyicINFO, Lilacs e Proquest, onde foram pesquisadas as produções bibliográficas de 2005 a 2011, utilizando os descritores “psychological tests” e “vocational guidance” (testes psicológicos e orientação profissional); “occupational choice” e “personality traits” (escolha profissional e características de personalidade) e “psychological assessment”, “vocational guidance” e “personality” (avaliação psicológica, orientação profissional e personalidade).Verificou-se que foram publicados poucos artigos que abordam o objetivo desta revisão, no entanto, a temática da orientação profissional é difundida em vários países, existindo vastas pesquisas e publicações na área. Os três estudos empíricos que sustentam a tese realizaram-se a partir da utilização da ficha de dados sociodemográficos, inventário de ansiedade de Beck (BAI), inventário de depressão de Beck (BDI-II), Inventário Fatorial de Personalidade (IFP), Questionário de Avaliação Tipológica (QUATI), Régua de Prontidão e teste Zulliger. Os estudos utilizaram o método quantitativo e transversal, sendo a amostra por conveniência. No total foram analisados os dados de 100 adolescentes, com idades entre 15 e 26 anos, que buscaram a orientação profissional do SAPP-PUCRS. A segunda seção teve como objetivo analisar as características sociodemográficas e de personalidade dos adolescentes; a terceira focou o processo de tomada de decisão e as características predominantes e, a quarta verificou a possível influência dos sintomas de ansiedade e de depressão na tomada de decisão. Concluiuse através dos estudos que algumas características de personalidade condizem com a fase em que os jovens se encontram, sendo observado uma tendência à extroversão, o apreço por movimentos e mudanças constantes, o uso do sentimento na tomada de decisões e na resolução de problemas, a presença de poucos recursos para dirigir e organizar condutas, podendo demonstrar certa impulsividade diante de algumas situações. Identificou-se a prontidão para a mudança em um processo de orientação profissional, existindo um predomínio do estilo vivencial introversão na tomada de decisão. O estudo também apontou que a maioria da população estudada obteve níveis mínimos e leves nas testagens que envolveram o BAI e o BDI-II, indicando esta sintomatologia dentro do esperado para uma população jovem e não-clínica, não sendo significativa a influência dos sintomas de ansiedade e de depressão na escolha profissional