38 research outputs found

    Fast all-optical switch

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    An apparatus and method wherein polarization rotation in alkali vapors or other mediums is used for all-optical switching and digital logic and where the rate of operation is proportional to the amplitude of the pump field. High rates of speed are accomplished by Rabi flopping of the atomic states using a continuously operating monochromatic atomic beam as the pump

    Full-duplex optical communication system

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    A method of full-duplex electromagnetic communication wherein a pair of data modulation formats are selected for the forward and return data links respectively such that the forward data electro-magnetic beam serves as a carrier for the return data. A method of encoding optical information is used wherein right-hand and left-hand circular polarizations are assigned to optical information to represent binary states. An application for an earth to low earth orbit optical communications system is presented which implements the full-duplex communication and circular polarization keying modulation format

    Testing the Tripartite Influence Model Among Heterosexual, Bisexual, and Lesbian Women

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    This cross-sectional study explored similarities and differences between heterosexual, bisexual, and lesbian women in levels of, and relationships between, the following constructs using a Tripartite Influence Model framework: family, peer, and media appearance pressures, thin- and muscular-ideal internalization, and eating disorder (ED) pathology. Self-identified heterosexual (n = 1,528), bisexual (n = 89), and lesbian (n = 278) undergraduate women completed the Sociocultural Attitudes Towards Appearance Questionnaire-4 and the Eating Disorder Examination-Questionnaire. Sexual orientation differences in appearance pressures, appearance-ideal internalization, and ED pathology were examined via analysis of variance tests. Relationships between these variables were examined with multi-group path analyses, controlling for age, race/ethnicity, and body mass index. Compared with lesbian women, heterosexual and bisexual women reported higher levels of peer appearance pressures. Paths from peer appearance pressures and thin-ideal internalization to shape/weight overvaluation and body dissatisfaction were strongest for bisexual women. Overall, results indicate notable similarities between heterosexual, bisexual, and lesbian women. However, preliminary evidence for potential differences highlights the importance of examining variation in ED risk between sexual minority subgroups

    Family Firms and Firm Performance: Evidence from Japan

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    Corrigendum: Nature Structural and Molecular Biology 16 (12), 1331 (2009) doi:10.1038/nsmb1209-1331bInternational audienceThioredoxins (Trxs) are oxidoreductase enzymes, present in all organisms, that catalyze the reduction of disulfide bonds in proteins. By applying a calibrated force to a substrate disulfide, the chemical mechanisms of Trx catalysis can be examined in detail at the single-molecule level. Here we use single-molecule force-clamp spectroscopy to explore the chemical evolution of Trx catalysis by probing the chemistry of eight different Trx enzymes. All Trxs show a characteristic Michaelis-Menten mechanism that is detected when the disulfide bond is stretched at low forces, but at high forces, two different chemical behaviors distinguish bacterial-origin from eukaryotic-origin Trxs. Eukaryotic-origin Trxs reduce disulfide bonds through a single-electron transfer reaction (SET), whereas bacterial-origin Trxs show both nucleophilic substitution (SN2) and SET reactions. A computational analysis of Trx structures identifies the evolution of the binding groove as an important factor controlling the chemistry of Trx catalysis

    The silver standard of the Ptolemaic coinage

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    I .o о to О о о юI .o о to О о о юHazzard R.A., Brown I.D. The silver standard of the Ptolemaic coinage. In: Revue numismatique, 6e série - Tome 26, année 1984 pp. 231-239

    Sexual Orientation Differences in Pathways from Sociocultural and Objectification Constructs to Body Satisfaction: The US Body Project I

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    Objectification theory and the tripartite influence model provide useful frameworks for understanding the body image experiences of men and women. However, there is little systematic investigation of how sexual orientation moderates the links between these constructs and body image satisfaction. It has been hypothesized, for example, that the associations of surveillance (i.e., monitoring of one’s appearance due to objectification by others) would be strongest for groups targeted by the male gaze (e.g., gay men, lesbian women, and bisexual men and women). Here we proposed an integrated sociocultural model and examined these pathways in multigroup structural equation models in a national sample of heterosexual, bisexual, and lesbian women (ns = 5395; 598; 213, respectively), and heterosexual, bisexual, and gay men (4869; 194; and 194, respectively) aged 18–65 years. Sexual orientation moderated some of these pathways. The most consistent pattern was that appearance pressures were internalized to a greater extent among bisexual participants. The pathways to poorer body image were generally similar among heterosexual and gay/lesbian men and women. These findings highlight the importance of examining sexual orientation-specific influences on body image across diverse groups, as well as the commonalities in the experiences of men and women across sexual orientations

    Racial Identity Differences in Pathways from Sociocultural and Objectification Constructs to Body Satisfaction: The U.S. Body Project I

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    Racial minority men and women face a wide variety of appearance-related pressures, including ones connected to their cultural backgrounds and phenotypic features associated with their identity. These body image concerns exist within a larger context, wherein racial minorities face pressures from multiple cultures or subcultures simultaneously to achieve unrealistic appearance ideals. However, limited research has investigated racial differences in the relationships between theorized sociocultural risk factors and body image in large samples. This study tests pathways from an integrated sociocultural model drawing on objectification theory and the tripartite influence model to three key body image outcomes: appearance evaluation, body image quality of life, and face image satisfaction. These pathways were tested using multigroup structural equation modeling in a national sample of White, Black, Hispanic, and Asian men and women (ns = 205–4797 per group). Although many hypothesized associations were similar in strength across groups, race moderated some of the pathways between sociocultural pressures (media, peer, family), internalization of appearance ideals (thin-ideal, muscular/athletic), appearance surveillance, and body image outcomes. Findings support the likely role of both shared and specific risk factors for body image outcomes, suggesting avenues for tailoring adapted interventions in order to target culturally-salient risk factors
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