Triple-q octupolar ordering in NpO_2

We report the results of resonant X-ray scattering experiments performed at the Np M_4,5 edges in NpO_2. Below T_0 = 25 K, the development of long-range order of Np electric quadrupoles is revealed by the growth of superlattice Bragg peaks. The electronic transition is not accompanied by any measurable crystallographic distortion, either internal or external, so the symmetry of the system remains cubic. The polarization and azimuthal dependence of the intensity of the resonant peaks is well reproduced assuming Templeton scattering from a triple-q longitudinal antiferroquadrupolar structure. Electric quadrupole order in NpO_2 could be driven by the ordering at T_0 of magnetic octupoles of Gamma_5 symmetry, splitting the Np ground state quartet and leading to a singlet ground state with zero dipole magnetic moment.Comment: 4 Pages, 3 Figures, submitted to Phys. Rev. Lett. v2: resubmitted after referee report

Multi-k⃗\vec{k} Configurations

Using resonant x-ray scattering to perform diffraction experiments at the U M$_{4}$ edge novel reflections of the generic form have been observed in UAs$_{0.8}$Se$_{0.2}$ where $\vec{k} = $, with $k = {1/2}$ reciprocal lattice units, is the wave vector of the primary (magnetic) order parameter. The reflections, with $10^{-4}$ of the magnetic intensities, cannot be explained on the basis of the primary order parameter within standard scattering theory. A full experimental characterisation of these reflections is presented including their energy, azimuthal and temperature dependencies. On this basis we establish that the reflections most likely arise from the electric dipole operator involving transitions between the core 3d and partially filled $5f$ states. The temperature dependence couples the peak to the triple-$\vec{k}$ region of the phase diagram: Below $\sim 50$ K, where previous studies have suggested a transition to a double-$\vec{k}$ state, the intensity of the $$ is dramatically reduced. Whilst we are unable to give a definite explanation of how these novel reflections appear, this paper concludes with a discussion of possible ideas for these reflections in terms of the coherent superposition of the 3 primary (magnetic) order parameters

"Eat and you will be eaten": a qualitative study exploring costs and benefits of age-disparate sexual relationships in Tanzania and Uganda: implications for girls' sexual and reproductive health interventions

BACKGROUND: Age-disparate sex is associated with increased HIV risk among adolescent girls and young women (AGYW) in sub-Saharan Africa. However, little has been done to understand the dynamics of such relationships from the perspectives of either AGYW or older men, and the communities in which these relationships are embedded. This article explores the motivations and perceived benefits of such relationships for AGYW and older men, plus the social and sexual and reproductive health (SRH) consequences. METHODS: This study held 37 participatory focus group discussions and 87 in-depth interviews with young people aged 14-24 and adult community members aged 25-49 in rural and urban Tanzania and Uganda. Participants were sampled using purposive and snowball techniques. Thematic analysis was conducted with the aid of NVIVO 10 software. RESULTS: Motivations, perceived benefits and costs for AGYW centred around four main themes: financial motivations, emotional support, meeting social expectations and reflections on sexual health. Specifically, AGYW noted that older partners gave gifts/money of higher value compared with younger men. Men's perceived benefits and costs revolved around the need to satisfy their sexual desire, the perception that AGYW were capable of engaging in new and creative sexual styles and their desire for prestige among male peers. Both AGYW and men recognised the social and SRH consequences as: risk of violence, social stigma, risk of unplanned pregnancy and risk of sexually transmitted infections including HIV. CONCLUSION: Interventions need to acknowledge the perceived benefits of age-disparate sexual relationships for AGYW and older men and engage them in critical reflection on the medium- to longer-term consequences versus the shorter-term satisfaction of needs, desires and aspirations, as a way to navigate the constrained opportunities they face given existing structural limitations. Interventions should also tackle the structural constraints AGYW face by helping them access resources, become empowered and challenge the expectation of having to depend financially on men. Interventions with men should unpack the assumption that men are naturally hypersexual. The role of peers for both girls and men should be acknowledged, and a shift from individual targeted interventions to changing norms at the community level should be considered

The Problematization of Sexuality among Women Living with HIV and a New Feminist Approach for Understanding and Enhancing Women’s Sexual Lives

In the context of HIV, women’s sexual rights and sexual autonomy are important but frequently overlooked and violated. Guided by community voices, feminist theories, and qualitative empirical research, we reviewed two decades of global quantitative research on sexuality among women living with HIV. In the 32 studies we found, conducted in 25 countries and composed mostly of cis-gender heterosexual women, sexuality was narrowly constructed as sexual behaviours involving risk (namely, penetration) and physiological dysfunctions relating to HIV illness, with far less attention given to the fullness of sexual lives in context, including more positive and rewarding experiences such as satisfaction and pleasure. Findings suggest that women experience declines in sexual activity, function, satisfaction, and pleasure following HIV diagnosis, at least for some period. The extent of such declines, however, is varied, with numerous contextual forces shaping women’s sexual well-being. Clinical markers of HIV (e.g., viral load, CD4 cell count) poorly predicted sexual outcomes, interrupting widely held assumptions about sexuality for women with HIV. Instead, the effects of HIV-related stigma intersecting with inequities related to trauma, violence, intimate relations, substance use, poverty, aging, and other social and cultural conditions primarily influenced the ways in which women experienced and enacted their sexuality. However, studies framed through a medical lens tended to pathologize outcomes as individual “problems,” whereas others driven by a public health agenda remained primarily preoccupied with protecting the public from HIV. In light of these findings, we present a new feminist approach for research, policy, and practice toward understanding and enhancing women’s sexual lives—one that affirms sexual diversity; engages deeply with society, politics, and history; and is grounded in women’s sexual rights

Key stakeholder perceptions about consent to participate in acute illness research: a rapid, systematic review to inform epi/pandemic research preparedness

Background A rigorous research response is required to inform clinical and public health decision-making during an epi/pandemic. However, the ethical conduct of such research, which often involves critically ill patients, may be complicated by the diminished capacity to consent and an imperative to initiate trial therapies within short time frames. Alternative approaches to taking prospective informed consent may therefore be used. We aimed to rapidly review evidence on key stakeholder (patients, their proxy decision-makers, clinicians and regulators) views concerning the acceptability of various approaches for obtaining consent relevant to pandemic-related acute illness research. Methods We conducted a rapid evidence review, using the Internet, database and hand-searching for English language empirical publications from 1996 to 2014 on stakeholder opinions of consent models (prospective informed, third-party, deferred, or waived) used in acute illness research. We excluded research on consent to treatment, screening, or other such procedures, non-emergency research and secondary studies. Papers were categorised, and data summarised using narrative synthesis. Results We screened 689 citations, reviewed 104 full-text articles and included 52. Just one paper related specifically to pandemic research. In other emergency research contexts potential research participants, clinicians and research staff found third-party, deferred, and waived consent to be acceptable as a means to feasibly conduct such research. Acceptability to potential participants was motivated by altruism, trust in the medical community, and perceived value in medical research and decreased as the perceived risks associated with participation increased. Discrepancies were observed in the acceptability of the concept and application or experience of alternative consent models. Patients accepted clinicians acting as proxy-decision makers, with preference for two decision makers as invasiveness of interventions increased. Research regulators were more cautious when approving studies conducted with alternative consent models; however, their views were generally under-represented. Conclusions Third-party, deferred, and waived consent models are broadly acceptable to potential participants, clinicians and/or researchers for emergency research. Further consultation with key stakeholders, particularly with regulators, and studies focused specifically on epi/pandemic research, are required. We highlight gaps and recommendations to inform set-up and protocol development for pandemic research and institutional review board processes