37 research outputs found

    Design Principles for Plasmonic Nanoparticle Devices

    Get PDF
    For all applications of plasmonics to technology it is required to tailor the resonance to the optical system in question. This chapter gives an understanding of the design considerations for nanoparticles needed to tune the resonance. First the basic concepts of plasmonics are reviewed with a focus on the physics of nanoparticles. An introduction to the finite element method is given with emphasis on the suitability of the method to nanoplasmonic device simulation. The effects of nanoparticle shape on the spectral position and lineshape of the plasmonic resonance are discussed including retardation and surface curvature effects. The most technologically important plasmonic materials are assessed for device applicability and the importance of substrates in light scattering is explained. Finally the application of plasmonic nanoparticles to photovoltaic devices is discussed.Comment: 29 pages, 15 figures, part of an edited book: "Linear and Non-Linear Nanoplasmonics

    Universal HIV testing in London tuberculosis clinics: a cluster randomised controlled trial

    Get PDF
    We assessed whether implementation of a combination of interventions in London tuberculosis clinics raised the levels of HIV test offers, acceptance and coverage. A stepped-wedge cluster randomised controlled trial was conducted across 24 clinics. Interventions were training of clinical staff and provision of tailor-made information resources with or without a change in clinic policy from selective to universal HIV testing. The primary outcome was HIV test acceptance amongst those offered a test, before and after the intervention; the secondary outcome was an offer of HIV testing. Additionally, the number and proportion of HIV tests among all clinic attendees (coverage) was assessed. 1,315 patients were seen in 24 clinics. The offer and coverage of testing rose significantly in clinics without (p = 0.002 and p = 0.004, respectively) and with an existing policy of universal testing (p = 0.02 and p = 0.04, respectively). However, the level of HIV test acceptance did not increase in 18 clinics without routine universal testing (p = 0.76) or the six clinics with existing universal testing (p = 0.40). The intervention significantly increased the number of HIV tests offered and proportion of participants tested, although acceptance did not change significantly. However, the magnitude of increase is modest due to the high baseline coverage

    Male Mating Tactics in Captive Rhesus Macaques (Macaca mulatta): The Influence of Dominance, Markets, and Relationship Quality

    Get PDF
    Male mating success in a multimale–multifemale group can depend on several variables: body condition, dominance, coalitions, “friendship,” or an exchange of services for mating access. Exchange patterns may also be determined by market effects or social relationships. We studied the mating tactics of males in a captive, multimale–multifemale group of rhesus macaques and the resulting patterns of mating and paternity to determine the influence of dominance rank, mating markets, and relationship quality on their mating tactics. Male rank was positively related to the total number of copulations and the number of mating partners, but did not explain male mating distribution completely. Moreover, male fertilization success was not related to male rank. Males did not exchange grooming for mating access on the same day and neither the supply nor the rank (as a proxy for quality) of receptive females affected the amount of male grooming, suggesting that market effects did not explain male mating access. However, there was a positive correlation between long-term grooming patterns of both males and females and mating access, indicating that social relationships were important for male mating access. Paternity data revealed that these social relationships were also important for male reproductive success. We conclude that both male rank and male–female “friendship” determined male mating access in these rhesus macaques, but that “friendship” was more important in determining paternity, emphasizing the importance of intersex social bonds in male mating success in multimale primate societies

    Gestational Hypoxia Inhibits Pregnancy-Induced Upregulation of Ca 2+

    Full text link
    corecore