900 resultados para mirror


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The Mendel database contains names for plant-wide families of sequenced plant genes. The names have either been approved by the Commission on Plant Gene Nomenclature (CPGN), an organization of the International Society for Plant Molecular Biology (ISPMB), or are identified as provisional or temporary names. Mendel also identifies the corresponding genes in individual species of plants. Mendel can be searched through the mirror sites at Cornell (http://genome.cornell.edu/cgi-bin/WebAce/webace?db=mendel) and Stanford (http://genome-www.stanford.edu/Mendel/). In addition, parts of Mendel can be downloaded from the CPGN Web site (http://mbclserver.rutgers.edu/CPGN/).

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The emergence of biochemical homochirality was a key step in the origin of life, yet prebiotic mechanisms for chiral separation are not well constrained. Here we demonstrate a geochemically plausible scenario for chiral separation of amino acids by adsorption on mineral surfaces. Crystals of the common rock-forming mineral calcite (CaCO3), when immersed in a racemic aspartic acid solution, display significant adsorption and chiral selectivity of d- and l-enantiomers on pairs of mirror-related crystal-growth surfaces. This selective adsorption is greater on crystals with terraced surface textures, which indicates that d- and l-aspartic acid concentrate along step-like linear growth features. Thus, selective adsorption of linear arrays of d- and l-amino acids on calcite, with subsequent condensation polymerization, represents a plausible geochemical mechanism for the production of homochiral polypeptides on the prebiotic Earth.

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Global diversity curves reflect more than just the number of taxa that have existed through time: they also mirror variation in the nature of the fossil record and the way the record is reported. These sampling effects are best quantified by assembling and analyzing large numbers of locality-specific biotic inventories. Here, we introduce a new database of this kind for the Phanerozoic fossil record of marine invertebrates. We apply four substantially distinct analytical methods that estimate taxonomic diversity by quantifying and correcting for variation through time in the number and nature of inventories. Variation introduced by the use of two dramatically different counting protocols also is explored. We present sampling-standardized diversity estimates for two long intervals that sum to 300 Myr (Middle Ordovician-Carboniferous; Late Jurassic-Paleogene). Our new curves differ considerably from traditional, synoptic curves. For example, some of them imply unexpectedly low late Cretaceous and early Tertiary diversity levels. However, such factors as the current emphasis in the database on North America and Europe still obscure our view of the global history of marine biodiversity. These limitations will be addressed as the database and methods are refined.

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The reactions of chimpanzees to regular mirrors and the results of the standard Gallup mark test have been well documented. In addition to using the mark test to demonstrate self-recognition in a regular mirror, we exposed six female chimpanzees to mirrors that produced distorted or multiplied self-images. Their reactions to their self-images, in terms of mirror-guided self-referenced behaviors, indicated that correct assessment of the source of the mirror image was made by each subject in each of the mirrors. Recognition of a distorted self-image implies an ability for abstraction in the subjects in that the distortion must be rationalized before self-recognition occurs. The implications of these results in terms of illuminating the relative importance of feature and contingency of movement cues to self-recognition are discussed.

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In each facet of the Drosophila compound eye, a cluster of photoreceptor cells assumes an asymmetric trapezoidal pattern. These clusters have opposite orientations above and below an equator, showing global dorsoventral mirror symmetry. However, in the mutant spiny legs, the polarization of each cluster appears to be random, so that no equator is evident. The apparent lack of an equator suggests that spiny legs+ may be involved in the establishment of global dorsoventral identity that might be essential for proper polarization of the photoreceptor clusters. Alternatively, a global dorsoventral pattern could be present, but spiny legs+ may be required for local polarization of individual clusters. Using an enhancer trap strain in which white+ gene expression is restricted to the dorsal field, we show that white+ expression in spiny legs correctly respects dorsoventral position even in facets with inappropriate polarizations; the dorsoventral boundary is indeed present, whereas the mechanism for polarization is perturbed. It is suggested that the boundary is established before the action of spiny legs+ by an independent mechanism.

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Self-recognition has been explored in nonlinguistic organisms by recording whether individuals touch a dye-marked area on visually inaccessible parts of their face while looking in a mirror or inspect parts of their body while using the mirror's reflection. Only chimpanzees, gorillas, orangutans, and humans over the age of approximately 2 years consistently evidence self-directed mirror-guided behavior without experimenter training. To evaluate the inferred phylogenetic gap between hominoids and other animals, a modified dye-mark test was conducted with cotton-top tamarins (Saguinus oedipus), a New World monkey species. The white hair on the tamarins' head was color-dyed, thereby significantly altering a visually distinctive species-typical feature. Only individuals with dyed hair and prior mirror exposure touched their head while looking in the mirror. They looked longer in the mirror than controls, and some individuals used the mirror to observe visually inaccessible body parts. Prior failures to pass the mirror test may have been due to methodological problems, rather than to phylogenetic differences in the capacity for self-recognition. Specifically, an individual's sensitivity to experimentally modified parts of its body may depend crucially on the relative saliency of the modified part (e.g., face versus hair). Moreover, and in contrast to previous claims, we suggest that the mirror test may not be sufficient for assessing the concept of self or mental state attribution in nonlinguistic organisms.

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A cetamina é uma droga amplamente utilizada e o seu uso inadequado tem sido associado à graves consequências para a saúde humana. Embora as propriedades farmacológicas deste agente em doses terapêuticas sejam bem conhecidas, existem poucos estudos sobre os efeitos secundários induzidos por doses não-terapêuticas, incluindo os efeitos nos estados de ansiedade e agressividade. Neste contexto, os modelos animais são uma etapa importante na investigação e elucidação do mecanismo de ação a nível comportamental. O zebrafish (Danio rerio) é um novo organismo-modelo, interessante e promissor, uma vez que apresenta alta similaridade fisiológica, genética e neuroquímica com seres humanos, respostas comportamentais bem definidas e rápida absorção de compostos de interesse em meio aquoso além de apresentar uma série de vantagens em relação aos modelos mamíferos tais como manutenção de baixo custo, prática e executável em espaços reduzidos. Nesse sentido, faz-se necessário a execução de ensaios comportamentais em conjunto com análises estatísticas robustas e rápidas tais como ANOVA e Métodos Multivariados; e também o desenvolvimento de métodos analíticos sensíveis, precisos e rápidos para determinação de compostos de interesse em matrizes biológicas provenientes do animal. Os objetivos do presente trabalho foram a investigação dos efeitos da cetamina sobre a ansiedade e a agressividade em zebrafish adulto empregando Testes de Claro-Escuro e Testes do Espelho e métodos estatísticos univariados (ANOVA) e multivariados (PCA, HCA e SIMCA) assim como o desenvolvimento de método analítico para determinação da cetamina em matriz biológica proveniente do animal, empregando Extração Líquido-Líquido e Cromatografia em Fase Gasosa acoplada ao Detector de Nitrogênio-Fósforo (GC-NPD). Os resultados comportamentais indicaram que a cetamina produziu um efeito significativo dose-dependente em zebrafish adulto na latência à área clara, no número de cruzamentos entre as áreas e no tempo de exploração da área clara. Os resultados das análises SIMCA e PCA mostraram uma maior similaridade entre o grupo controle e os grupos de tratamento expostos às doses mais baixas (5 e 20 mg L-1) e entre os grupos expostos às doses de 40 e 60 mg L-1. Na análise por PCA, dois componentes principais responderam por 88,74% de toda a informação do sistema, sendo que 62,59% da informação cumulativa do sistema foi descrito pela primeira componente principal. As classificações HCA e SIMCA seguiram uma evolução lógica na distribuição das amostras por classes. As doses mais altas de cetamina induziram uma distribuição mais homogênea das amostras enquanto as doses mais baixas e o controle resultaram em distribuições mais dispersas. No Teste do Espelho, a cetamina não induziu efeitos significativos no comportamento dos animais. Estes resultados sugerem que a cetamina é modulador de comportamentos ansiosos, sem efeitos indutores de agressividade. Os resultados da validação do método cromatográfico indicaram uma extração com valores de recuperação entre 33,65% e 70,89%. A curva de calibração foi linear com valor de R2 superior a 0,99. O limite de detecção (LOD) foi de 1 ng e o limite de quantificação (LOQ) foi de 5 ng. A exatidão do método cromatográfico manteve-se entre - 24,83% e - 1,258%, a precisão intra-ensaio entre 2,67 e 14,5% e a precisão inter-ensaio entre 1,93 e 13,9%.

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A cold atomic cloud is a versatile object, because it offers many handles to control and tune its properties. This facilitates studies of its behavior in various circumstances, such as sample temperature, size and density, composition, dimensionality and coherence time. The range of possible experiments is constrained by the specifications of the atomic species used. In this thesis presents the work done in the experiment for laser cooling of strontium atoms, focusing on its stability, which should provide cold and ultracold samples for the study of collective effects in light scattering. From the initial apparatus, innumerous changes were performed. The vacuum system got improved and now reached lower ultra high vacuum due to the pre-baking done to its parts and adding a titanium-sublimation stage. The quadrupole trap were improved by the design and construction of a new pair of coils. The stability of the blue, green and red laser systems and the loss prevention of laser light were improved, giving rise to a robust apparatus. Another important point is the development of homemade devices to reduce the costs and to be used as a monitor of different parts of an cold atoms experiment. From this homemade devices, we could demonstrate a dramatic linewidth narrowing by injection lock of an low cost 461 nm diode laser and its application to our strontium experiment. In the end, this improved experimental apparatus made possible the study of a new scattering effect, the mirror assisted coherent back-scattering (mCBS).

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Transnational artist Shahzia Sikander challenges the limitations of Edward Said's postcolonial emphasis on secular humanism by deploying the heterogeneous traditions of South Asian miniature painting while strategically drawing on tradition to critique contemporaneity. Through a palimpsest process of composition, Sikander reincorporates the unknown and silenced histories implicit in the tradition of miniature painting to create social imaginaries with motifs that draw on the diverse traditions of South Asian religions and aesthetics to create a subversive politics of remembering wherein alternative images of cosmopolitanism emerge. Through a sustained analysis, this dissertation demonstrates how these alternative traditions interrogate and critique the limitations of postcolonial theory. Particularly important to this critique are some recent approaches of Third World feminists that highlight the limitations of secular humanism implicit in much of postcolonial critique. Sikander's compositions mirror these approaches as her motifs of the feminine become an intervention into the spiritual emptiness and ethical confusions of contemporaneity. In effect, Sikander's work is an intervention, a warning, and a plea for the re-invention of positive alternatives as her images embody and facilitate a critical and daring consciousness that is necessary to both our social and spiritual well-being.

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Specific training for conducting psychotherapy with gay men is limited for psychologists, particularly when using a Self Psychology theoretical orientation (Robertson, 1996). In fact, psychologists often are faced with conflicting and contradictory points of view that mirror society's condemnation of homosexuality (Robertson, 1996). This paper is written from a self-psychological perspective to address the lack of a constructive body of literature that explains the unique treatment needs which impact gay men. Estimates of the prevalence of male homosexuality have generated considerable debate. A common assumption is that there are homosexual and non-homosexual men. However, scientists have long been aware that sexual responsiveness to others of the same sex, like most human traits, is continuously distributed in the population (Michaels, 1996). Still the presumption exists that such traits are stable within each man over time (Michaels, 1996). Conflating same-sex sexual experiences with a categorization of the man as homosexual is problematic, in that defining sexuality solely on the basis of experience excludes people who fantasize about sex with others of the same sex but never have sexual contact. Thus, most modern conceptions of sexual orientation consider personal identification, sexual behavior, and sexual fantasy (McWhirter, Sanders & Reinisch, 1990). Gay men's mental health can only be understood in the context of homosexuality throughout history, since religious and moral objections to sexual attraction between men have existed for centuries. Men who desired other men were regarded as sinful and depraved if not ill or abnormal, and same sex contacts were not distinguished from lewd behaviors (Weeks, 1989). Although most people, regardless of sexual orientation, have experienced some feelings of personal rejection, rarely do heterosexuals become targets for disapproval based on the nature of their attractions and behaviors relative to the same and to the other sex. For lesbians, bisexuals, and gay men, however, homosexuality becomes the focus of aspects of themselves that make them feel hated and hateful (Isay, 1989). While gay men and lesbians are often considered together because of the same-sex nature of their relationships and the similar issues that they may experience in their treatment within society, there are many issues where they might be best studied separately. Issues involving with health, parenthood, sexuality and perceived roles and status in society, for example, are often related more to gender than to any shared concept of a 'gay and lesbian community'. Many issues surrounding lesbians and lesbian culture will have more to do with women's issues, and some issues involving with gay men will have more to do with the gay male subculture and with masculinity. The author of this paper has limited experience in working with lesbian and bisexual individuals, and although it is likely that some of the concepts articulated in this paper could translate to working with lesbian and bisexual individuals, further research is indicated to examine the beneficence of utilizing a Self Psychological orientation in psychotherapy with lesbian women and bisexual individuals. This paper presents an overview of the literature including historical treatments of homosexuality, the history of Self Psychology, key principles in Self Psychology, research on Self Psychology, identity development models for gay men, and Self Psychological perspectives on identity development related to gay men. The literature review is followed by a section on treatment implications for psychologists seeking to treat gay men, including case vignettes based on work from my own practice. I have preserved the anonymity of clients by changing demographics, and rearranging and combining presenting issues and historical backgrounds among the case examples.

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Students in urban schools who are negatively impacted need stability and continuity the most. However, at least half of new teachers leave their profession within five years. In order for this situation to change, support is needed for new teachers and encouragement is needed for experienced teachers. The purpose of the study is to offer a first-hand description of factors that affect the profession of teaching and especially teachers who may be wondering how to stay in teaching for more than five years. Veteran teachers gain the opportunity to reflect, validate, and (probably) celebrate their own journey through this profession. This autoethnography uses my experience of a 29-year veteran teacher, who started with an alternative teaching license, to mirror what researchers have identified as key factors for sustainability and how they affected my continued commitment to teaching in urban schools. The following questions framed the study: 1. Why did I choose teaching as a career? 2. What supportive factors contributed to my decision to continue teaching in an urban school rather than leave the profession? 3. What internal and external struggles have I encountered in teaching and what strategies did I use to overcome them? 4. What beliefs and experiences led to my steadfast commitment to teaching in an urban setting? 5. How do I define success as an urban teacher? 6. What are the implications of my story for urban education? This autoethnography involves data collection and in-depth analysis of documents and artifacts that were generated during my teaching career as an urban educator. These documents and artifacts come from both internal and external sources. The study’s implications reach beyond teachers and include two sub-groups: teacher education programs and school administrators. The implication for teachers is the importance of a two-fold support system in order to thrive: first teachers need spiritual support and second they need to surround themselves with likeminded teachers. The implications for teacher education programs include making pre-service teachers aware of the realities of urban settings and provide them with resources, which could help overcome the attrition rate. Additionally, pre-service teachers need to know how to form credible relationships with their students. This study also reveals the important role that school principals play in the success of their teachers. First, principals are responsible for creating a positive school climate that promotes a professional learning community. Second, they need to establish relational trust in their building. Third, they need to nourish their staff both physically and emotionally. Finally, the implications of autoethnography for teachers and researchers are also discussed.

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The use of 3D imaging techniques has been early adopted in the footwear industry. In particular, 3D imaging could be used to aid commerce and improve the quality and sales of shoes. Footwear customization is an added value aimed not only to improve product quality, but also consumer comfort. Moreover, customisation implies a new business model that avoids the competition of mass production coming from new manufacturers settled mainly in Asian countries. However, footwear customisation implies a significant effort at different levels. In manufacturing, rapid and virtual prototyping is required; indeed the prototype is intended to become the final product. The whole design procedure must be validated using exclusively virtual techniques to ensure the feasibility of this process, since physical prototypes should be avoided. With regard to commerce, it would be desirable for the consumer to choose any model of shoes from a large 3D database and be able to try them on looking at a magic mirror. This would probably reduce costs and increase sales, since shops would not require storing every shoe model and the process of trying several models on would be easier and faster for the consumer. In this paper, new advances in 3D techniques coming from experience in cinema, TV and games are successfully applied to footwear. Firstly, the characteristics of a high-quality stereoscopic vision system for footwear are presented. Secondly, a system for the interaction with virtual footwear models based on 3D gloves is detailed. Finally, an augmented reality system (magic mirror) is presented, which is implemented with low-cost computational elements that allow a hypothetical customer to check in real time the goodness of a given virtual footwear model from an aesthetical point of view.

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El regreso de los Borbones en 1814, a pesar del agresivo programa de extrema derecha que trajo consigo, según el cual pretendía acabar con el aparato del Estado centralizado por considerarlo la fuente misma del “peligro revolucionario”, no mermó en ningún caso el poder de una administración que había sido muy poco depurada. El realismo ultra rápidamente demostró su incapacidad para estabilizar la economía y la sociedad mediante un compromiso histórico que, sin embargo, fue rápidamente organizado por una tecnocracia compuesta por una fusión de los despachos de la Francia anterior a 1789 y los del episodio revolucionario e imperial. Entre lecciones de Turgot y de Corbert, el Estado se hizo el guardián y el tutor de un liberalismo económico y social que dotó de un nuevo impuso a la industrialización de Francia y a la formación de un mercado nacional protegido. Esta identidad modernizadora del Estado supo evolucionar. Sobrevivió al giro a la derecha de la vida política propiciado por Villèle y, para hacer frente a las dificultades que se encontró Francia en su modernización a partir de 1828, el Estado se propuso aprender de los “métodos ingleses” que hicieron evolucionar la rigidez de la administración napoleónica.

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We propose a simple yet efficient method for generating in-plane hollow beams with a nearly full circular light shell without the contribution of backward propagating waves. The method relies on modulating the phase in the near field of a centrosymmetric optical wave front, such as that from a high-numerical-aperture focused wave field. We illustrate how beam acceleration may be carried out by using an ultranarrow non-flat meta-surface formed by engineered plasmonic nanoslits. A mirror-symmetric, with respect to the optical axis, circular caustic surface is numerically demonstrated that can be used as an optical bottle.

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When the GoPro camera was first put on the market in 2004, it brought about a new generation of ultracompact cameras designed to be attached to the user’s body, and which came to be known as action cams. Their principal characteristics were their tiny size, their high-quality images and a wide-angle, fixed-focal-length lens. This combination has made it much simpler to get spectacular subjective shots with considerable depth of field. The users of this technology now form a whole generation of citizen-filmmakers who produce thousands of videos every day in a novel realistic style dominated by first-person narrative. Their work is principally shared via video platforms like YouTube and Vimeo, which provide instant feedback in the form of millions of views. In this paper we analize the common features of the action cam recording style and we state these videos will bring about a redefinition of the realist visual style. Furthermore, we propose to relate the success of the action cam phenomenon with the cognitive concept of embodiment and argue that the viewer’s mirror neurons copy the real sensations and enable the viewer to experience, virtually and in safety, the same emotions felt by the person actually taking part in the action.