20 research outputs found
Promotion of couples' voluntary counselling and testing for HIV through influential networks in two African capital cities
<p>Abstract</p> <p>Background</p> <p>Most new HIV infections in Africa are acquired from cohabiting heterosexual partners. Couples' Voluntary Counselling and Testing (CVCT) is an effective prevention strategy for this group. We present our experience with a community-based program for the promotion of CVCT in Kigali, Rwanda and Lusaka, Zambia.</p> <p>Methods</p> <p>Influence Network Agents (INAs) from the health, religious, non-governmental, and private sectors were trained to invite couples for CVCT. Predictors of successful promotion were identified using a multi-level hierarchical analysis.</p> <p>Results</p> <p>In 4 months, 9,900 invitations were distributed by 61 INAs, with 1,411 (14.3%) couples requesting CVCT. INAs in Rwanda distributed fewer invitations (2,680 vs. 7,220) and had higher response rates (26.9% vs. 9.6%), than INAs in Zambia. Context of the invitation event, including a discreet location such as the INA's home (OR 3.3–3.4), delivery of the invitation to both partners in the couple (OR 1.6–1.7) or to someone known to the INA (OR 1.7–1.8), and use of public endorsement (OR 1.7–1.8) were stronger predictors of success than INA or couple-level characteristics.</p> <p>Conclusion</p> <p>Predictors of successful CVCT promotion included strategies that can be easily implemented in Africa. As new resources become available for Africans with HIV, CVCT should be broadly implemented as a point of entry for prevention, care and support.</p
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Erratum to: Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species
Background: Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests. Results: We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes. Conclusions: The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant
Nanotechnology and Risk Governance in the European Union: the Constitution of Safety in Highly Promoted and Contested Innovation Areas
[EN]The European Union (EU) is strategically committed to the development of nanotechnology and its industrial exploitation. However, nanotechnology also has the potential to disrupt human health and the environment. The EU claims to be committed to the safe and responsible development of nanotechnology. In this sense, the EU has become the first governing body in the world to develop nanospecific regulations, largely due to legislative action taken by the European Parliament, which has compensated for the European Commission’s reluctance to develop special regulations for nanomaterials. Nevertheless, divergences aside, political bodies in the EU assume that nanotechnology development
is controllable and take for granted that both the massive industrial use of nanomaterials and a high level
of environmental and health protection are compatible. However, experiences such as the European controversy over agri-food biotechnology, which somewhat delegitimized the regulatory authority of the EU over technological safety and acceptability, arguably show that controllability assumptions are contestable on the grounds of alternative socio-economic and cultural preferences and values. Recently developed inclusive governance models on safety and innovation, such as"Responsible Research and Innovation" (RRI), widelyclaim that a diversity of considerations and issues areintegrated into R&D processes. Even so, the possibility of more radically alternative constitutions of sociotechnical safety seems to be seriously limited by the current ideology of innovation and economic imperatives of the global, knowledge-based, capitalist economy.This work is based mainly upon research supported by the Basque Government’s Department of Education, Universities and Research under a Postdoctoral Fellowship for the Improvement of Research Personnel in a Foreign Country (grant BFI08.183). It has also been supported by the Basque Government’s Department of Education, Language Policy and Culture (grant IT644-13), the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (grant FFI2015-69792-R), and the University of the Basque Country UPV/EHU (grant EHUA15/13). The author also wishes to thank Heather A. Okvat for her assistance in revising the initial, original version of the article, and to two anonymous reviewers for their constructive and thorough comments on the present version. Any shortcomings in the work remain the responsibility of the author