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Time-course of effects of external beam radiation on [18F]FDG uptake in healthy tissue and bone marrow.
The utility of PET for monitoring responses to radiation therapy have been complicated by metabolically active processes in surrounding normal tissues. We examined the time-course of [18F]FDG uptake in normal tissues using small animal-dedicated PET during the 2 month period following external beam radiation. Four mice received 12 Gy of external beam radiation, in a single fraction to the left half of the body. Small animal [18F]FDG-PET scans were acquired for each mouse at 0 (pre-radiation), 1, 2, 3, 4, 5, 8, 12, 19, 24, and 38 days following irradiation. [18F]FDG activity in various tissues was compared between irradiated and non-irradiated body halves before, and at each time point after irradiation. Radiation had a significant impact on [18F]FDG uptake in previously healthy tissues, and time-course of effects differed in different types of tissues. For example, liver tissue demonstrated increased uptake, particularly over days 3-12, with the mean left to right uptake ratio increasing 52% over mean baseline values (p < 0.0001). In contrast, femoral bone marrow uptake demonstrated decreased uptake, particularly over days 2-8, with the mean left to right uptake ratio decreasing 26% below mean baseline values (p = 0.0005). Significant effects were also seen in lung and brain tissue. Radiation had diverse effects on [18F]FDG uptake in previously healthy tissues. These kinds of data may help lay groundwork for a systematically acquired database of the time-course of effects of radiation on healthy tissues, useful for animal models of cancer therapy imminently, as well as interspecies extrapolations pertinent to clinical application eventually
Risk Factors for Delayed Viral Suppression on First-Line Antiretroviral Therapy among Persons Living with HIV in Haiti, 2013-2017
Studies of viral suppression on first-line antiretroviral therapy (ART) in persons living with human immunodeficiency virus (PLHIV) in Haiti are limited, particularly among PLHIV outside of the Ouest department, where the capital Port-au-Prince is located. This study described the prevalence and risk factors for delayed viral suppression among PLHIV in all geographic departments of Haiti between 2013 and 2017. Individuals who received viral load testing 3 to 12 months after ART initiation were included. Data on demographics and clinical care were obtained from the Haitian Active Longitudinal Tracking of HIV database. Multivariable logistic regression was performed to predict delayed viral suppression, defined as a viral load ≥1000 HIV-1 RNA copies/mL after at least 3 months on ART. Viral load test results were available for 3,368 PLHIV newly-initiated on ART. Prevalence of delayed viral suppression was 40%, which is slightly higher than previous estimates in Haiti. In the multivariable analysis, delayed viral suppression was significantly associated with younger age, receiving of care in the Ouest department, treatment with lamivudine (3TC), zidovudine (AZT), and nevirapine (NVP) combined ART regimen, and CD4 counts below 200 cells/mm3. In conclusion, this study was the first to describe and compare differences in delayed viral suppression among PLHIV by geographic department in Haiti. We identified populations to whom public health interventions, such as more frequent viral load testing, drug resistance testing, and ART adherence counseling should be targeted
Capture and Recycle of Industrial CO\u3csub\u3e2\u3c/sub\u3e Emissions Using Mircoalgae
A novel cyclic flow photobioreactor (PBR) for the capture and recycle of CO2 using microalgae was designed and deployed at a coal-fired power plant (Duke Energy’s East Bend Station). The PBR was operated continuously during the period May–September 2015, during which algae productivity of typically 0.1–0.2 g/(L day) was obtained. Maximum CO2 capture efficiency was achieved during peak sunlight hours, the largest recorded CO2 emission reduction corresponding to a value of 81 % (using a sparge time of 5 s/min). On average, CO2 capture efficiency during daylight hours was 44 %. The PBR at East Bend Station also served as a secondary scrubber for NOx and SOx, removing on average 41.5 % of the NOx and 100 % of the SOx from the flue gas. The effect of solar availability and self-shading on a rudimentary digital model of the cyclic flow PBR was examined using Autodesk Ecotect Analysis software. Initial results suggest that this is a promising tool for the optimization of PBR layout with respect to the utilization of available solar radiation
Capture and Recycle of Industrial CO\u3csub\u3e2\u3c/sub\u3e Emissions Using Mircoalgae
A novel cyclic flow photobioreactor (PBR) for the capture and recycle of CO2 using microalgae was designed and deployed at a coal-fired power plant (Duke Energy’s East Bend Station). The PBR was operated continuously during the period May–September 2015, during which algae productivity of typically 0.1–0.2 g/(L day) was obtained. Maximum CO2 capture efficiency was achieved during peak sunlight hours, the largest recorded CO2 emission reduction corresponding to a value of 81 % (using a sparge time of 5 s/min). On average, CO2 capture efficiency during daylight hours was 44 %. The PBR at East Bend Station also served as a secondary scrubber for NOx and SOx, removing on average 41.5 % of the NOx and 100 % of the SOx from the flue gas. The effect of solar availability and self-shading on a rudimentary digital model of the cyclic flow PBR was examined using Autodesk Ecotect Analysis software. Initial results suggest that this is a promising tool for the optimization of PBR layout with respect to the utilization of available solar radiation
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