14 research outputs found
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Chemical Fixation of CO2 in Coal Combustion Products and Recycling through Biosystems
This Annual Technical Progress Report presents the principle results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. A co-current reactor is present that increases the gas phase to bicarbonate transfer rate by a factor of five to nine. The bicarbonate concentration at a given pH is approximately double that obtained using a control column of similar construction. Algae growth experiments were performed under laboratory conditions to obtain baseline production rates and to perfect experimental methods. The final product of this initial phase in algae production is presented
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CHEMICAL FIXATION OF CO2 IN COAL COMBUSTION PRODUCTS AND RECYCLING THROUGH BIOSYSTEMS
This Annual Technical Progress Report presents the principle results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. A co-current reactor is present that increases the gas phase to bicarbonate transfer rate by a factor of five to nine. The bicarbonate concentration at a given pH is approximately double that obtained using a control column of similar construction. Algae growth experiments were performed under laboratory conditions to obtain baseline production rates and to perfect experimental methods. The final product of this initial phase in algae production is presented. Algal growth can be limited by several factors, including the level of bicarbonate available for photosynthesis, the pH of the growth solution, nutrient levels, and the size of the cell population, which determines the available space for additional growth. In order to supply additional CO2 to increase photosynthesis and algal biomass production, fly ash reactor has been demonstrated to increase the available CO2 in solution above the limits that are achievable with dissolved gas alone. The amount of dissolved CO2 can be used to control pH for optimum growth. Periodic harvesting of algae can be used to maintain algae in the exponential, rapid growth phase. An 800 liter scale up demonstrated that larger scale production is possible. The larger experiment demonstrated that indirect addition of CO2 is feasible and produces significantly less stress on the algal system. With better harvesting methods, nutrient management, and carbon dioxide management, an annual biomass harvest of about 9,000 metric tons per square kilometer (36 MT per acre) appears to be feasible. To sequester carbon, the algal biomass needs to be placed in a permanent location. If drying is undesirable, the biomass will eventually begin to aerobically decompose. It was demonstrated that algal biomass is a suitable feed to an anaerobic digester to produce methane. The remaining carbonaceous material is essentially bio-inactive and is permanently sequestered. The feasibility of using algae to convert carbon dioxide to a biomass has been demonstrated. This biomass provides a sustainable means to produce methane, ethanol, and/or bio diesel. The first application of concept demonstrated by the project could be to use algal biomass production to capture carbon dioxide associated with ethanol production
Trends in Prevalence of Advanced HIV Disease at Antiretroviral Therapy Enrollment - 10 Countries, 2004-2015.
Monitoring prevalence of advanced human immunodeficiency virus (HIV) disease (i.e., CD4+ T-cell count <200 cells/μL) among persons starting antiretroviral therapy (ART) is important to understand ART program outcomes, inform HIV prevention strategy, and forecast need for adjunctive therapies.*,†,§ To assess trends in prevalence of advanced disease at ART initiation in 10 high-burden countries during 2004-2015, records of 694,138 ART enrollees aged ≥15 years from 797 ART facilities were analyzed. Availability of national electronic medical record systems allowed up-to-date evaluation of trends in Haiti (2004-2015), Mozambique (2004-2014), and Namibia (2004-2012), where prevalence of advanced disease at ART initiation declined from 75% to 34% (p<0.001), 73% to 37% (p<0.001), and 80% to 41% (p<0.001), respectively. Significant declines in prevalence of advanced disease during 2004-2011 were observed in Nigeria, Swaziland, Uganda, Vietnam, and Zimbabwe. The encouraging declines in prevalence of advanced disease at ART enrollment are likely due to scale-up of testing and treatment services and ART-eligibility guidelines encouraging earlier ART initiation. However, in 2015, approximately a third of new ART patients still initiated ART with advanced HIV disease. To reduce prevalence of advanced disease at ART initiation, adoption of World Health Organization (WHO)-recommended "treat-all" guidelines and strategies to facilitate earlier HIV testing and treatment are needed to reduce HIV-related mortality and HIV incidence
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Exposure to HIV partner counseling and referral services and notification of sexual partners among persons recently diagnosed with HIV.
ObjectiveAmong HIV-infected persons, we evaluated use of client partner notification (CPN) and health-department partner notification strategies to inform sex partners of possible HIV exposure, and prior exposure to partner counseling and referral services.MethodsWe conducted a cross-sectional, observational study of 590 persons diagnosed with HIV in the prior 6 months at 51 HIV test, medical, and research providers in Chicago and Los Angeles in 2003 and 2004. Logistic regression was used to identify independent correlates of using CPN to notify all locatable partners.ResultsParticipants reported a total of 5091 sex partners in the 6 months preceding HIV diagnosis; 1253 (24.6%) partners were locatable and not known to be HIV-positive. Of 439 participants with ≥1 locatable partners, 332 (75.6%) reported notifying 696 (55.5%) partners by CPN (585, 84.1%), health-department partner notification (94, 13.5%), or other means (17, 2.4%); 208 (47.4%) used CPN to notify all locatable partners. Independent correlates of CPN included having fewer locatable partners and discussing the need to notify partners with an HIV medical-care provider (black and Hispanic participants only). Many participants reported that their HIV test or medical-care provider did not discuss the need to notify partners (48.8%, 33.7%, respectively) and did not offer health-department partner-notification services (60.8%, 52.8%).ConclusionMany locatable sex partners who might benefit from being notified of potential HIV exposure are not notified. In accordance with national policies, HIV test and medical-care providers should routinely provide partner counseling and referral services to HIV-infected clients so that all locatable partners are notified and provided an opportunity to learn their HIV status
Recommended from our members
Exposure to HIV partner counseling and referral services and notification of sexual partners among persons recently diagnosed with HIV.
ObjectiveAmong HIV-infected persons, we evaluated use of client partner notification (CPN) and health-department partner notification strategies to inform sex partners of possible HIV exposure, and prior exposure to partner counseling and referral services.MethodsWe conducted a cross-sectional, observational study of 590 persons diagnosed with HIV in the prior 6 months at 51 HIV test, medical, and research providers in Chicago and Los Angeles in 2003 and 2004. Logistic regression was used to identify independent correlates of using CPN to notify all locatable partners.ResultsParticipants reported a total of 5091 sex partners in the 6 months preceding HIV diagnosis; 1253 (24.6%) partners were locatable and not known to be HIV-positive. Of 439 participants with ≥1 locatable partners, 332 (75.6%) reported notifying 696 (55.5%) partners by CPN (585, 84.1%), health-department partner notification (94, 13.5%), or other means (17, 2.4%); 208 (47.4%) used CPN to notify all locatable partners. Independent correlates of CPN included having fewer locatable partners and discussing the need to notify partners with an HIV medical-care provider (black and Hispanic participants only). Many participants reported that their HIV test or medical-care provider did not discuss the need to notify partners (48.8%, 33.7%, respectively) and did not offer health-department partner-notification services (60.8%, 52.8%).ConclusionMany locatable sex partners who might benefit from being notified of potential HIV exposure are not notified. In accordance with national policies, HIV test and medical-care providers should routinely provide partner counseling and referral services to HIV-infected clients so that all locatable partners are notified and provided an opportunity to learn their HIV status
The Young Men’s Survey Phase II: Hepatitis B Immunization and Infection Among Young Men Who Have Sex With Men
Objectives. We measured the prevalence of hepatitis B virus (HBV) immunization and HBV infection among men aged 23 to 29 years who have sex with men
HIV Infection and Testing among Latino Men Who Have Sex with Men in the United States: The Role of Location of Birth and Other Social Determinants
BACKGROUND: In the United States, Latino men who have sex with men (MSM) are disproportionately affected by HIV. Latino MSM are a diverse group who differ culturally based on their countries or regions of birth and their time in the United States. We assessed differences in HIV prevalence and testing among Latino MSM by location of birth, time since arrival, and other social determinants of health. METHODS: For the 2008 National HIV Behavioral Surveillance System, a cross-sectional survey conducted in large US cities, MSM were interviewed and tested for HIV infection. We used generalized estimating equations to test associations between various factors and 1) prevalent HIV infection and 2) being tested for HIV infection in the past 12 months. RESULTS: Among 1734 Latino MSM, HIV prevalence was 19%. In multivariable analysis, increasing age, low income, and gay identity were associated with HIV infection. Moreover, men who were U.S.-born or who arrived ≥5 years ago had significantly higher HIV prevalence than recent immigrants. Among men not reporting a previous positive HIV test, 63% had been tested for HIV infection in the past 12 months; recent testing was most strongly associated with having seen a health care provider and disclosing male-male attraction/sexual behavior to a health care provider. CONCLUSIONS: We identified several social determinants of health associated with HIV infection and testing among Latino MSM. Lower HIV prevalence among recent immigrants contrasts with higher prevalence among established immigrants and suggests a critical window of opportunity for HIV prevention, which should prioritize those with low income, who are at particular risk for HIV infection. Expanding health care utilization and encouraging communication with health care providers about sexual orientation may increase testing
HIV Prevention Services Received at Health Care and HIV Test Providers by Young Men who Have Sex with Men: An Examination of Racial Disparities
We investigated whether there were racial/ethnic differences among young men who have sex with men (MSM) in their use of, perceived importance of, receipt of, and satisfaction with HIV prevention services received at health care providers (HCP) and HIV test providers (HTP) that explain racial disparities in HIV prevalence. Young men, aged 23 to 29 years, were interviewed and tested for HIV at randomly sampled MSM-identified venues in six U.S. cities from 1998 through 2000. Analyses were restricted to five U.S. cities that enrolled 50 or more black or Hispanic MSM. Among the 2,424 MSM enrolled, 1,522 (63%) reported using a HCP, and 1,268 (52%) reported having had an HIV test in the year prior to our interview. No racial/ethnic differences were found in using a HCP or testing for HIV. Compared with white MSM, black and Hispanic MSM were more likely to believe that HIV prevention services are important [respectively, AOR, 95% confidence interval (CI): 3.0, 1.97 to 4.51 and AOR, 95% CI: 2.7, 1.89 to 3.79], and were more likely to receive prevention services at their HCP (AOR, 95% CI: 2.5, 1.72 to 3.71 and AOR, 95% CI: 1.7, 1.18 to 2.41) and as likely to receive counseling services at their HTP. Blacks were more likely to be satisfied with the prevention services received at their HCP (AOR, 95% CI: 1.7, 1.14 to 2.65). Compared to white MSM, black and Hispanic MSM had equal or greater use of, perceived importance of, receipt of, and satisfaction with HIV prevention services. Differential experience with HIV prevention services does not explain the higher HIV prevalence among black and Hispanic MSM
Toward next-generation primate neuroscience: A collaboration-based strategic plan for integrative neuroimaging
Open science initiatives are creating opportunities to increase research coordination and impact in nonhuman primate (NHP) imaging. The PRIMatE Data and Resource Exchange community recently developed a collaboration-based strategic plan to advance NHP imaging as an integrative approach for multiscale neuroscience