• Title/Summary/Keyword: mosquito

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Mosquito Net type Harmful Air Breaker (방충망형 오염공기 차단기)

  • Hwang, Dong-Hyeon;Kim, Yong-Jin;Lee, Woo-Cheol
    • Proceedings of the KIPE Conference
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    • 2015.11a
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    • pp.175-176
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    • 2015
  • 봄철 황사나 대기오염으로 인하여 실내에 오염된 공기가 유입되고 있다. 이를 정화하기위해 현재 실내에서는 공기청정기를 사용한다. 그러나 기존의 공기청정기는 이미 실내공기가 오염되었을 때 작동한다. 이를 보완하고자 본 논문에서는 방충망형 오염공기 차단기를 제안하였다. 방충망형 오염공기 차단기는 방충망에 고압의 DC 전압을 인가하여 코로나현상을 일어나게 하도록 만든 장치이다. 코로나 현상이 일어나면 주변 공기가 이온화 되는 원리를 이용하였다. 고압의 DC 전압을 발생시키기 위해 Full-Bridge 인버터를 이용하여 LC공진으로 변압기의 1차측 전압을 상승시켰고, 권선비를 이용하여 변압기 2차측 전압을 승압하였다. 마지막으로 배전압 정류회로를 설계하여 최종 DC전압을 생성하였다. 실험을 통해 제안한 방식의 유용성을 검증하였다.

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A Critical Analysis of Intracranial Hemorrhage as a Fatal Complication of Dengue Fever

  • Andre Marolop Pangihutan Siahaan;Steven Tandean;Bahagia Willibrordus Maria Nainggolan;Junita Tarigan;Johan Samuel Sitanggang
    • Journal of Korean Neurosurgical Society
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    • v.66 no.5
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    • pp.494-502
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    • 2023
  • Dengue fever is the most rapidly spreading mosquito-borne virus in the world, infecting about 100 million individuals. A rare but possibly dangerous consequence of dengue illness is intracranial hemorrhage (ICH). Currently, the pathogenesis of ICH is unknown. A number of studies have found a variety of risk factors for ICH in dengue. In addition, studies have reported the use of emergency surgery while monitoring thrombocytopenia in the therapy of dengue ICH. This review enumerates the potential predictors of ICH in dengue, discusses the use of brain imaging, and mentions the possibility of emergency surgery.

Seasonal Prevalence of the Vector Mosquitoes of Japanese Encephalitis Virus in Kyungpook Province, Korea (경북지역에서의 일본뇌염 매개모기에 출현 소장)

  • 주종윤;화전의인
    • Parasites, Hosts and Diseases
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    • v.23 no.1
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    • pp.139-150
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    • 1985
  • In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook Province, a survey based on average numbers of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34, 571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 per cent were Culex tritaeniorhynchus, 34.0 per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23.2 per cent), and C. pipiens pallens(O.6 per cent). In the general pattern of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance differed from that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this Province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates (1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing a simple sharply pointed one-peaked curve.

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Characterization of Bacillus thuringiensis subsp. tohokuensis CAB167 Isolate against Mosquito Larva (모기유충에 활성 있는 Bacillus thuringiensis subsp. tohokuensis CAB167 균주의 특성)

  • Kil, Mi-Ra;Kim, Da-A;Paek, Seung-Kyoung;Kim, Jin-Su;Choi, Su-Yeon;Jin, Da-Yong;Youn, Young-Nam;Hwang, In-Chon;Ohba, Michio;Yu, Yong-Man
    • Korean journal of applied entomology
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    • v.47 no.4
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    • pp.457-465
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    • 2008
  • Eight Bacillus thuringiensis strains activated against mosquito larva were compared their characterization. Spherical-shaped parasporal inclusion of B. thuringiensis subsp. tohokuensis CAB167 was observed by phase-contrast microscopy and scanning electron microscopy. $LC_{50}$ values of B. thuringiensis subsp. tohokuensis CAB167 against Culex pipiens molestus, Culex pipiens pallens, and Aedes aegyti were 173, 190 and 580 ng/ml, respectively. B. thuringiensis subsp. tohokuensis CAB167 had a parasporal inclusion containing 4 major protein components, for example, 135, 80, 49 and 28-kDa by SDS-PAGE. Otherwise, after trypsin digestion of parasporal inclusion, SDS-PAGE was showed new protease-resistant peptides at 72 and 63-kDa. Activated toxins of isolated CAB167 were different from other reference strains on a serological by immuno-diffusion test.

Distribution of Biota and Removal Efficiency of Organic Matter in Natural Wetland (농촌배수처리용 습지의 생물상 및 유기물 제거율)

  • Kim, Bum-Chul;Jeon, Man-Sik;Jung, Geun;Jung, Yeon-Sook;Hwang, Gil-Soon
    • Korean Journal of Environmental Biology
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    • v.17 no.4
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    • pp.407-414
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    • 1999
  • Distribution of biota and removal efficiency of organic matter in natural wetland systems were examined from June to October 1998. The aquatic macrophyte communities were consisted of 13 families and 22 species. The composition of occurrence species were as follows: Phragmites communis Trinius are 35%, Persicaria thunbergii Nakai are 19%, Typha angustifolia L. are 17%, Bidens tripartita L. are 16%, Echinochloa crus-galli (L.) Beauv. are 12% and others are l%. The fauna collected from 5 sites consisted of total 6 classes of macroinvertebrates. The composition of occurrence classes were as follows: Insecta are 76%, O1igochaeta are 19%, Gastrapoda are 4% and others are 1%. These included 18 families, 7 orders of Insects. The larve and mosquito and midges were found in wetlands. Preventive strategies are needed for the suppression of mosquito at the stage of wetland planning and design. In wetland, removal efficiency of dissolved organic carbon is low because of primary production and the background level of DOC in the wetland discharge seems to be 5 mgC/1, but those of BOD was ca. 50%. Wetlands receiving water of low concentration can not work as purification field.

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Indoor Rearing Method of Diving Beetles: Cybister japonicus, Cybister tripunctatus orientalis, Cybister brevis (물방개류 실내 사육법)

  • Kim, NamJung;Hong, Seong-Jin;Kim, Seong-Hyun;Park, Hae-Chul
    • Journal of Sericultural and Entomological Science
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    • v.50 no.1
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    • pp.27-32
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    • 2012
  • The aim of this study is to develop indoor-rearing methods of the diving beetles. In nature, both the adult diving beetle and its larvae are voracious aquatic predators. The larvae beetles hunt relatively bigger size of tadpoles and small fish for food source. However, due to difficulties of the food supplement for rearing diving beetles at indoor-condition further motivated us to develop new artificial food. Three separate experiments were performed. In the first experiment, adult beetles were provided with one of the several food choice treatments to self-compose their preferred foods that are affordable on the market at lower price. The second experiment was also to develop artificial diet that is possible for rearing larvae beetle under indoor condition. The larvae beetles were restricted to raw squid, artificial food source and mosquito larvae as a control at the first stadium and small fish and raw squid during second to third stadium duration. According to our result, adult beetles selected a food that made of boiled squid and dead small fish while, the young larvae consumed small fish, mosquito larvae and raw squid. Although, the larval food restriction on law squid caused noticeable decrease in survival, the result still supported the possible survival rate of keeping larvae at indoor condition. Moreover, pupation rate experiments, in which groups of larvae were placed at different mats, natural soil and fermented sawdust, showed that 80% of diving beetles pupated on the sawdust. This result indicates that female beetle preferentially selected to oviposit along soft and moist area.

Discrimination of Flaviviruses with High Frequency of Infection in Asian Countries: Epitope Prediction by Bioinformatic Approaches (아시아 국가 내에서 감염빈도가 높은 플라비바이러스의 구별: 생물정보학적 접근을 통한 항원결정기 예측)

  • Choi, Jae-Won;Jo, Byung-Gwan;Kim, Min Jung;Park, Suji;Kim, Hak Yong
    • The Journal of the Korea Contents Association
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    • v.18 no.4
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    • pp.99-113
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    • 2018
  • Recently, global warming has widened the habitat of mosquitoes and infection chances for mosquito-borne diseases are increasing. Flavivirus is a typical mosquito-borne virus. Flaviviruses with a relatively high frequency of infection in Asian countries include Zika, Dengue, and Japanese encephalitis viruses. Although distinctive diagnosis of flaviviruses is required because the symptoms and therapeutic method differ, there is no diagnostic method that can distinguish them accurately yet. In this study, we propose distinctive diagnosis method of flaviviruses using informations and analysis tools constructed in bioinformatic databases. The envelope protein and non-structural protein 1 which are useful protein for the immuno-diagnostics of three flaviviruses were selected. Their homology was analyzed by multiple sequence alignments and epitope candidates consisting of 10-15 amino acids were selected. Finally two epitopes were suggested to be most useful by immunogenicity analysis and 3D structure prediction. These approaches and results are expected to be great value in the distinctive diagnosis of three flaviviruses with a high frequency of infection in Asian countries.

Extraction and Biological Activities of Essential Oil from Thuja occidental Leaves (서양측백나무 잎으로부터 식물정유 추출 및 생리활성)

  • Seo, Weon-Taek;Yang, Jae-Kyung;Kang, Byung-Kuk;Park, Woo-Jin;Hong, Seong-Cheol;Kang, Young-Min;Jung, Hee-Young;Kim, Yong-Duck;Kang, Seung-Mi;Kim, Seon-Won;Choi, Myung-Suk
    • Korean Journal of Medicinal Crop Science
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    • v.11 no.5
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    • pp.364-370
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    • 2003
  • Essential oil of Thuja occidental leaves was extracted by steam distillation method, and chemical composition of essential oil was analyzed by GC-MS. The essential oil was tested to antimicrorbiaI activity against 28 test microorganisms and antioxident assay through DPPH free radical scaveging test and insecticidal activity by mosquito insecticide assay. The major constituents in the essential oil of T. occidental were monoterpene as d-isothujone, ${\alpha}-thujone$, camphor, L-fenchone, and hornyl acetate. The essential oil have broad antimicrobiaI activity, which showed strong antimicrobiaI activity for Streptococcus pyogenes as bacteria, Alternaria alternata, Aspergillus niger, Aspergillus oryzae, Saccharomyces cerevisiae, and Streptococcus mutans as fungi. The essential oil also showed DPPH free radical scavenging ability at concentration of $36\;{\mu}{\ell}/m{\ell}$. In spraying and fumigation tests, the essential oil had strong insecticidal activity against mosquito.

Biological Control of Malaria Vector (Anopheles sinensis Wied.) by Combined Use of Larvivorous Fish (Aplocheilus latipes) and Herbivorous Hybrid (Tilapia mossambicus niloticus) and Herbivorous Hybrid (Tilapia mossambicus niloticus) in Rice Paddies of Korea (천적포식어 (Aplocheilus latipes)와 식식성 어류 (Tilapia mossambicus niloticus) 의 병합적 처리에 의한 논에 서식하는 말라리아 매개모기 (Anopheles sinensis Wied.) 의 생물학적 방제)

  • 유효석;이준학
    • Korean journal of applied entomology
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    • v.28 no.4
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    • pp.229-236
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    • 1989
  • A combined field release of indigenous larvivoroug fish (Aplocheilus latipes) and hybrid herbivore (Tilapia mossambicus miloticus) was conducted to determine the effectiveness of biological control, in particular, against malaria vector (anopheles sinensis), breeding in weedy habitat of rice fields at the University rice paddies at Suwon during the period of June through September in 1988. A combined fish introduction at the release rate of 2.0 fish per $M^{2}$ for Aplocheilus and 1-pair $10M^{2}$ water surface for Tilapia resuited in 70.8% Anopheles larval reducton in a week period, the rates of rontrol increased to 73. 5% and 80.2% in 4th and 5th week respectively after the fish introdurtion, maintaining mosquito suppression in range of 80~82% control after the 5th week against Anopheles and Culex spp. combined. In a single fish treatment with Aplocheilus at 2.0 $fish/M^{2}$ release rate, Anopheles larval reduction ranged on the average 51.4~56.5%in 4 wrek period which was later integratpd with B.t.i. (Rl53.78) treatment at 1.0 kg/ha dosage rate to suppress vector mosquito population down and the the results was compared with that of combined fish introdurtion.

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Studies on the Current Epidemiological Situation of Brugian Filariasis in Endemic Areas of Korea (최근 국내 사상충증의 역학적 상황에 관한 조사)

  • 백영한;조유정
    • Parasites, Hosts and Diseases
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    • v.26 no.4
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    • pp.255-262
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    • 1988
  • An epidemiological study on brugian filariasis was carried out in endemic areas including Cheju Island in Korea, with a brief review of literatures. The results showed that the incidence among residents has remarkably decreased in Cheju Island, which was the main endemic area. Reviewing available informations on the prevalence of filariasis reported in recent years and also judging from the present socio·economic conditions which enable people to practice personal protection against mosquitos, it can be said with confidence that alariasis has almost disappeared from Cheju Island and inland areas. The disease is considered to remain at a low level of endemicity in Hugsan Islands. Certainly mass diethylcarbamasine (DEC) treatment carried out in Cheju Island in the 1960s and 1970s and remarkable economic growth followed by improved living standard and altered life-style of inhabitants could all have combined effects on the disappearance of this mosquito-borne disease in this island. If the present trends go on, the possibility of resurgence of filariasis in Cheju Island is hardly postulated.

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