29 research outputs found

    The Venus Balloon Project

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    On June 11 and 15, 1985, two instrumental balloons were released from the Soviet VEGA 1 and VEGA 2 spacecraft and deployed in the atmosphere of Venus. The VEGA probes flew by the planet on their way to a rendezvous with comet Halley in March 1986. Drifting with the wind at altitudes of 54 km, the balloons traveled one-third of the way around the planet during their 46-hour lifetimes. Sensors on-board the gondolas made periodic measurements of pressure, temperature, vertical wind velocity, cloud particle density, ambient light level, and frequency of lightning. The data were transmitted to Earth and received at the Deep Space Network (DSN) 64-m stations and at several large antennas in the USSR. Approximately 95 percent of the telemetry data were successfully decoded at the DSN complexes and in the Soviet Union, and were provided to the international science team for analysis. Very Long Baseline Interferometry (VLBI) data were acquired by 20 radio observatories around the world for the purpose of monitoring the Venus winds. The DSN 64-m subnet was part of a 15-station VLBI network organized by the Centre National d'Etudes Spatiales (CNES) of France. In addition, five antennas of the Soviet network participated. VLBI data from the CNES network are currently being processed at the Jet Propulsion Laboratory

    Ka-band study: 1988

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    The Ka-band study team was chartered in late 1987 to bring together all the planning elements for establishing 32 GHz (Ka-band) as the primary downlink frequency for deep-space operation, and to provide a stable baseline from which to pursue that development. This article summarizes the results of that study at its conclusion in mid-1988, and corresponds to material presented to NASA's Office of Space Operations on July 14, 1988. For a variety of reasons, Ka-band is the right next major step in deep-space communications. It offers improved radio metric accuracy through reduced plasma sensitivity and increased bandwidth. Because of these improvements, it offers the opportunity to reduce costs in the flight radio system or in the DSN by allocating part of the overall benefits of Ka-band to this cost reduction. A mission scenario is being planned that can drive at least two and possibly all three of the DSN subnets to provide a Ka-band downlink capability by the turn of the century. The implementation scenario devised by the study team is believed to be feasible within reasonable resource expectations, and capable of providing the needed upgrade as a natural follow-on to the technology development which is already underway

    Interventions for families affected by HIV

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    Family-based interventions are efficacious for human immunodeficiency virus (HIV) detection, prevention, and care, but they are not broadly diffused. Understanding intervention adaptation and translation processes can support evidence-based intervention (EBI) diffusion processes. This paper provides a narrative review of a series of EBI for families affected by HIV (FAH) that were adapted across five randomized controlled trials in the US, Thailand, and South Africa over 15 years. The FAH interventions targeted parents living with HIV and their children or caregiver supports. Parents with HIV were primarily mothers infected through sexual transmission. The EBIs for FAH are reviewed with attention to commonalities and variations in risk environments and intervention features. Frameworks for common and robust intervention functions, principles, practice elements, and delivery processes are utilized to highlight commonalities and adaptations for each location, time period, and intervention delivery settings. Health care, housing, food, and financial security vary dramatically in each risk environment. Yet, all FAH face common health, mental health, transmission, and relationship challenges. The EBIs efficaciously addressed these common challenges and were adapted across contexts with fidelity to robust intervention principles, processes, factors, and practices. Intervention adaptation teams have a series of structural decision points: mainstreaming HIV with other local health priorities or not; selecting an optimal delivery site (clinics, homes, community centers); and how to translate intervention protocols to local contexts and cultures. Replication of interventions with fidelity must occur at the level of standardized functions and robust principles, processes, and practices, not manualized protocols. Adopting a continuous quality improvement paradigm will enhance rapid and global diffusion of EBI for FAH

    Contraceptive use among HIV-infected women and men receiving antiretroviral therapy in Lusaka, Zambia: a cross-sectional survey

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    Abstract Background Family planning (FP) is an essential health service and an important part of comprehensive HIV care. However, there is limited information about the contraceptive needs of people living with HIV in sub-Saharan Africa, which in turn has hampered efforts to expand and integrate FP services into existing HIV programs. Methods We performed a cross-sectional survey to determine FP prevalence and predictors among HIV-positive women and men attending 18 public antiretroviral therapy (ART) clinics in Lusaka, Zambia. Trained peer counselors administered the 10-question survey to those seeking care for five days at each of the target sites. Results From February to April 2014, we surveyed 7,046 HIV-infected patients receiving routine HIV services. Use of modern contraception was reported by 69 % of female ART patients and 79 % of male ART patients. However, highly effective contraceptive use and dual method use were low among women (38 and 25 %, respectively) and men (19 and 14 %, respectively). HIV disclosure status (adjusted odds ratio (AOR) = 4.91, 95 % confidence interval (CI) = 3.32–7.24 for women, AOR = 3.58, 95 % CI = 2.39–5.38 for men) and sexual activity in the last 6 months (AOR = 5.80, 95 % CI = 4.51–7.47 for women, AOR = 6.24, 95 % CI = 3.51–11.08 for men) were associated with modern contraceptive use in multivariable regression. Most respondents said they would access FP services if made available within ART clinic. Conclusions While FP-ART integration may be a promising strategy for increasing FP service uptake, such services must focus on assessing sexual activity and advocating for dual method use to increase effective contraceptive use and prevent unintended pregnancies

    Experiences of health care providers with integrated HIV and reproductive health services in Kenya: a qualitative study.

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    BACKGROUND: There is broad consensus on the value of integration of HIV services and reproductive health services in regions of the world with generalised HIV/AIDS epidemics and high reproductive morbidity. Integration is thought to increase access to and uptake of health services; and improves their efficiency and cost-effectiveness through better use of available resources. However, there is still very limited empirical literature on health service providers and how they experience and operationalize integration. This qualitative study was conducted among frontline health workers to explore provider experiences with integration in order to ascertain their significance to the performance of integrated health facilities. METHODS: Semi-structured in-depth interviews were conducted with 32 frontline clinical officers, registered nurses, and enrolled nurses in Kitui district (Eastern province) and Thika and Nyeri districts (Central province) in Kenya. The study was conducted in health facilities providing integrated HIV and reproductive health services (post-natal care and family planning). All interviews were conducted in English, transcribed and analysed using Nvivo 8 qualitative data analysis software. RESULTS: Providers reported delivering services in provider-level and unit-level integration, as well as a combination of both. Provider experiences of actual integration were mixed. At personal level, providers valued skills enhancement, more variety and challenge in their work, better job satisfaction through increased client-satisfaction. However, they also felt that their salaries were poor, they faced increased occupational stress from: increased workload, treating very sick/poor clients, and less quality time with clients. At operational level, providers reported increased service uptake, increased willingness among clients to take an HIV test, and reduced loss of clients. But the majority also reported infrastructural and logistic deficiencies (insufficient physical room space, equipment, drugs and other medical supplies), as well as increased workload, waiting times, contact session times and low staffing levels. CONCLUSIONS: The success of integration primarily depends on the performance of service providers which, in turn, depends on a whole range of facilitative organisational factors. The central Ministry of Health should create a coherent policy environment, spearhead strategic planning and ensure availability of resources for implementation at lower levels of the health system. Health facility staffing norms, technical support, cost-sharing policies, clinical reporting procedures, salary and incentive schemes, clinical supply chains, and resourcing of health facility physical space upgrades, all need attention. Yet, despite these system challenges, this study has shown that integration can have a positive motivating effect on staff and can lead to better sharing of workload - these are important opportunities that deserve to be built on
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