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국내 사람면역결핍바이러스 감염 및 후천면역결핍증후군의 현황과 전망
No full textBackground: Over the past decade, approximately 1,100 newly diagnosed cases of human immunodeficiency virus (HIV) infection have been reported annually in South Korea, with 1,066 newly diagnosed cases reported in 2022. A decrease in HIV infection rate can be achieved only through coordinated prevention, diagnosis, and treatment. South Korea is lagging in the worldwide decreasing trend of HIV infection, and a brief review of this situation may suggest improvements necessary for progress. Current Concepts: In South Korea, the proportion of patients with CD4 cell count below 200 cells/mm3 at initial diagnosis of HIV infection remains high, suggesting that a significant population is diagnosed at the late stage of the disease. Since 2019, the Korean National Health Insurance Service began to cover the cost of pre-exposure prophylaxis for sexual partners of patients living with HIV, but few have started the regimen due to several barriers. Insurance criteria for a prophylaxis regimen should be modified, and accessibility to the regimen should be made available through multiple pathways. Proactive use of rapid HIV testing kits in community health centers and clinics should be expanded. Legal and administrative environments encouraging voluntary testing, early diagnosis, and treatment should be fostered. Medical personnel must be able to offer medical care without discrimination regardless of HIV infection status. Discussion and Conclusion: The HIV epidemic in South Korea has not yet decreased. To end it, efforts should be required across broad areas, including voluntary HIV testing, early diagnosis, active pre-exposure prophylaxis, a stigma- and discrimination-free social environment, and changes in legal and medical environments
Novel micropumps using gases as pumping sources
No full textThis paper presents several micropumps which generate pumping power through the chemical production of gas. Decomposition of hydrogen peroxide by aid of catalyst results in the production of oxygen. Hydrogen peroxide is separated by paraffin from catalyst before reaction. The decomposition of hydrogen peroxide by catalyst is initiated through melting the paraffin by an underlaid microheater. An initial triggering of the micropump by input of electric current is sufficient for the continuous actuation through the decomposition reaction. The operation of oxygen micropump can be tightly controlled if hydrogen peroxide is decomposed only by heating with microheater. For the production of carbon dioxide, sodium bicarbonate in a chamber is decomposed by heating. Alternatively, water droplet is caged by paraffin layer and released by heating. The released water dissolves citric acid powder and then, sodium bicarbonate reacts with citric acid and carbon dioxide is produced
A micropump operating with chemically produced oxygen gas
No full textA novel oxygen micropump is described in this paper. Pumping power is generated through the chemical production of oxygen gas. Decomposition of hydrogen peroxide by aid of catalyst results in the production of oxygen. Hydrogen peroxide is separated by oily paraffin from catalyst before the start of decomposition reaction. The decomposition of hydrogen peroxide by catalyst is commenced through melting the paraffin by an underlaid microheater. An initial triggering of the micropump by input of electric current is sufficient for the continuous actuation through the decomposition reaction. Liquid sample in reservoir is pushed by the produced oxygen gas and flows through a microchannel. Commercially available thin paraffin layers can replace paraffin for easier fabrication. Moreover, the operation of oxygen micropump can be tightly controlled if hydrogen peroxide is decomposed only by heating. Oxygen micropump will be a preferable component of lab-on-a-chips (LOCs) as well as the source of pure oxygen for chemical systems. (C) 2003 Elsevier B.V. All rights reserved
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