• 제목/요약/키워드: surface sterilization

검색결과 129건 처리시간 0.044초

감마선에 의한 감귤 궤양병균의 불활성화와 감귤 궤양병 감염에 미치는 영향 (Inactivation of Xanthomonas citri subsp. citri and Effect on Infection of Citrus Canker by Gamma Irradiation)

  • 김경남;송민아;한상헌;송성준;전용철
    • 식물병연구
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    • 제20권4호
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    • pp.283-288
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    • 2014
  • 감귤 궤양병은 Xanthomonas citri subsp. citri에 의해 발생하는 병으로서 많은 나라에서 이 병에 대해 검역을 실시하고 있다. 최근 methyl bromide의 검역 시 사용이 제한됨에 따라 감마선을 이용한 농수축산물에 대한 살균 방안이 대두되고 있다. 본 연구에서는 현탁액 형태의 감귤 궤양병균과 생과실 과피에 존재하는 감귤 궤양병균의 밀도를 감소시킬 수 있는 감마선의 선량을 알아보았다. 미생물의 밀도를 90% 감소시키는 선량인 감귤 궤양병균의 $D_{10}$ value는 현탁액과 감귤 생과실 과피에서 각각 55와 28 Gy였다. 또한 감마선을 처리한 감귤 궤양병균 현탁액을 감귤 잎에 접종하였더니 병 발생이 억제되었다. 본 연구를 통하여 감마선 처리에 의해 감귤 생과실에 존재하는 감귤 궤양병균을 박멸할 수 있다고 판단되며 본 연구 결과는 감마선을 검역에 활용하는데 가치가 있다고 생각된다.

맥류(麥類) 불임발생(不稔發生)의 환경요인(環境要因)에 관한 연구 - 입지조건(立地條件) 및 토양수분(土壤水分)을 중심(中心)으로 - (A study on the environmental conditions of barley and wheat sterilization - In preference to term of location and soil moisture -)

  • 박경배;정연태;노영팔;박래경
    • 한국토양비료학회지
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    • 제12권1호
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    • pp.25-34
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    • 1979
  • '77/'78맥작기간 영남지방(嶺南地方)에서 발생(發生)한 맥류불임현상의 원인(原因)을 구명(究明)하기 위하여 이것과 관련(關聯)되는 몇가지 환경요인(環境要因)을 조사(調査)해 본 결과(結果). 1. 기상상태(氣象狀態)는 특(特)히 보리의 주요생육시기(主要生育時期)에 해당(該當)되는 감수분열기(減數分裂期) 및 출수기경(出穗期頃)에 심(甚)한 조발(早魃)과 저온(低溫)이 내습(來襲)하였다. 2. 토양수분함량(土壤水分含量)은 전작(田作)보다 답리작(畓裏作)에서, 표토(表土)보다 심토(深土)에서 많았으며, 사토(砂土)보다는 식토(埴土)가 많았고, 남향(南向)보다 북향(北向)으로 된 경사지(傾斜地)에서 많은 경향(傾向)이었다. 3. 입지조건(立地條件)에 따른 보리이삭의 불임율(不稔率)은 답리(畓裏)이 전작(田作)보다 낮았고, 비상지(扉狀地) 및 평탄지(平坦地)는 구릉지(丘陵地), 산록경사지(山麓傾斜地)보다 낮았고, 남향(南向)보다 북향(北向)으로 된 경사지(傾斜地)가 낮은 편(便)이었다. 4. 경지(耕地)의 토성별(土性別) 불임율(不稔率)은 사토(砂土)에서 높았고, 식토(埴土)에서 낮았으며 작토호(作土戶) 및 유효토심이 얕을수록 높은 경향(傾向)이었다. 5. 답리작(畓裏作), 전작(田作) 다같이 표토(表土) 및 심토(深土)의 토양수분함량(土壤水分含量)과 보리이삭의 불임율(不稔率)과는 부(負)의 상관관계(相關關係)가 인정(認定)되었다. 6. 따라서 맥수 생식생장기간(生殖生長期間)의 주요시기(主要時期)에 수분부족(水分不足)은 수(穗)의 불임발생(不稔發生)의 주요원인(主要原因)으로 인정(認定)되었고, 이와함께 극심(極甚)한 저온(低溫)은 불임발생(不稔發生)을 더욱 조장(助長)하는 것으로 생각된다.

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Optical Diagnostics of Nanopowder Processed in Liquid Plasmas

  • Bratescu, M.A.;Saito, N.;Takai, O.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.17-18
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    • 2011
  • Plasma in liquid phase has attracted great attention in the last few years by the wide domain of applications in material processing, decomposition of organic and inorganic chemical compounds and sterilization of water. The plasma in liquid is characterized by three main regions which interact each - other during the plasma operation: the liquid phase, which supply the plasma gas phase with various chemical compounds and ions, the plasma in the gas phase at atmospheric pressure and the interface between these two regions. The most complex region, but extremely interesting from the fundamental, chemical and physical processes which occur here, is the boundary between the liquid phase and the plasma gas phase. In our laboratory, plasma in liquid which behaves as a glow discharge type, is generated by using a bipolar pulsed power supply, with variable pulse width, in the range of 0.5~10 ${\mu}s$ and 10 to 30 kHz repetition rate. Plasma in water and other different solutions was characterized by electrical and optical measurements. Strong emissions of OH and H radicals dominate the optical spectra. Generally water with 500 ${\mu}S/cm$ conductivity has a breakdown voltage around 2 kV, depending on the pulse width and the repetition rate of the power supply. The characteristics of the plasma initiated in ultrapure water between pairs of different materials used for electrodes (W and Ta) were investigated by the time-resolved optical emission and the broad-band absorption spectroscopy. The deexcitation processes of the reactive species formed in the water plasma depend on the electrode material, but have been independent on the polarity of the applied voltage pulses. Recently, Coherent anti-Stokes Raman Spectroscopy method was employed to investigate the chemistry in the liquid phase and at the interface between the gas and the liquid phases of the solution plasma system. The use of the solution plasma allows rapid fabrication of the metal nanoparticles without being necessary the addition of different reducing agents, because plasma in the liquid phase provides a reaction field with a highly excited energy radicals. We successfully synthesized gold nanoparticles using a glow discharge in aqueous solution. Nanoparticles with an average size of less than 10 nm were obtained using chlorauric acid solutions as the metal source. Carbon/Pt hybrid nanostructures have been obtained by treating carbon balls, synthesized in a CVD chamber, with hexachloro- platinum acid in a solution plasma system. The solution plasma was successfully used to remove the template remained after the mesoporous silica synthesis. Surface functionalization of the carbon structures and the silica surface with different chemical groups and nanoparticles, was also performed by processing these materials in the liquid plasma.

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제주지역 치위생과 학생의 COVID-19와 감염관리 임상실습 수행 실태 (Clinical Practice of COVID-19 and Infection Control by Dental Hygiene Students in Jeju Province)

  • 백수정;우재만;김성준
    • 한국콘텐츠학회논문지
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    • 제22권2호
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    • pp.370-378
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    • 2022
  • 본 연구의 목적은 제주 치위생과 학생을 대상으로 COVID-19 상황에 임상 실습 수행 중 감염관리에 영향을 미치는 요인을 분석하는 데 있다. 112명의 온라인 자기 기입식 설문 응답을 SPSS 20.0을 이용하여 빈도분석, T-test, one-way ANOVA와 더미 회귀분석을 하였다. 감염관리 인식도와 실천도는 2학년이 3학년보다 '청소 및 표면 소독', '의료폐기물 처리', 'COVID-19 감염관리' 항목에서 통계적으로 유의하게 높았다. 임상실습기관별 결과는 '청소 및 표면 소독', '기구 소독 및 멸균', '개인 및 환자 방호', 'COVID-19 감염관리' 항목에서 대형병원이 통계적으로 유의하게 높았다. 임상실습 지역은 의료폐기물 처리' 항목에서만 수도권이 제주지역보다 높았다. COVID-19 감염관리 요인 분석 결과, 3학년보다 2학년, 실습 기관 중 대형병원, 실습 지역 중 수도권 지역, 보호장구 애로사항이 없던 학생이 통계적으로 높은 영향을 미치는 것으로 나타났다. 본 연구는 제주지역 치위생과 학생들의 임상 실습시의 감염관리와 COVID-19의 현장을 대상으로 한 첫 번째 실태 조사 연구로 의의를 두며, 임상 실습 지침 개선을 위한 연구가 지속되어야 할 것이다.

항진균성 펩티드에 의한 표고버섯 푸른곰팡이병의 억제 (Suppression of green mold disease on oak mushroom cultivation by antifungal peptides)

  • 이형진;윤영배;허정훈;김영기
    • Journal of Applied Biological Chemistry
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    • 제60권2호
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    • pp.149-153
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    • 2017
  • 원목과 톱밥배지에서 푸른곰팡이의 오염과 성장은 표고버섯의 생장을 심하게 저해할 수 있다. 표고버섯 재배에서 푸른곰팡이병의 방제를 위하여 농약과 항생제와 같은 화학 약품의 사용은 일반적으로 허용되지 않는다. 본 연구에서는 푸른곰팡이병의 방제를 위하여 느타리버섯에서 갈반병을 일으키는 세균성 병원균을 분리하고 이들의 펩티드 독소를 분리하였다. Pseudomonas tolaasii 균주들은 항진균 활성을 갖는 톨라신 및 이와 구조적 유사체인 다양한 펩티드 독소를 분비한다. 이러한 펩티드들은 표고버섯의 생장에는 영향을 주지 않는다는 것이 알려져 있다. 펩티드 독소들을 Trichoderma harzianum H1 푸른곰팡이에 처리하였을 때, 푸른곰팡이의 성장을 저해하였다. 펩티드를 분비하는 20 종의 P. tolaasii 균주 중에서 강, 중, 약의 항진균 활성을 가진 균주의 수는 각각 8, 5, 7 종으로 나타났다. 표고버섯을 재배하는 동안에, 펩티드 독소를 함유한 세균 배양액에서 세균을 제거한 배양원액을 톱밥배지 표면에 자란 푸른곰팡이 균사에 분무하였다. 배양원액은 푸른곰팡이의 성장은 억제할 수 있는 반면, 표고버섯 생장과 생산에는 영향을 주지 않았다. 펩티드 독소를 함유하는 배양원액은 곰팡이의 흰색 균사체를 노란색의 마른 딱지로 변화시켰고, 이것은 펩티드 독소가 강력한 항진균 활성과 살균 활성을 갖고 있음을 보여준다.

일회용침 단체표준의 개발과 향후 전망 (Perspective on the Development of the Cooperation Group Standards of Acupuncture Needles for Single Use in Korea)

  • 장인수;김장현;박재현;박종배;박히준;서정철;송호섭;이인환;이향숙;최선미;한창호;구성태
    • 대한한의학회지
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    • 제27권3호
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    • pp.222-226
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    • 2006
  • Objective: The aim of this study was to introduce newly developed cooperation group standards of acupuncture needles for single use and to make a contribution to the future development of Korean Industrial Standards (KS) of acupuncture needles for single use. Results and Conclusion: Quality assurance and quality control with high safety profile is one of the most critical issues in medical device manufacturing. Up to now, proper attention has not been paid to this issue with respect to acupuncture needles for single use and their related devices. We, therefore, organized a committee to make guidelines to produce an acupuncture needle with high quality and safety. In the committee, we reviewed the topic from an historical viewpoint, and investigated the current situation of the standardization of acupuncture needles in other developed countries. Finally, we developed the cooperation group standards in advance of development of KS on the acupuncture needles for single use. The standards are composed of 12 sections describing: Scope, Normative references, Definitions, Materials, Configuration, Appearance and Cleanliness, Quality, Sterilization and Safety, Processing of Surface and Coating Material, Test, Packaging, and Labeling. We hope that the standards would be useful guidelines to produce high quality acupuncture needles and play an important role in the development of KS in the future.

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레토르트 파우치 미반(米飯)의 가열살균에 관한 연구 (Studies on the Thermal Processing of Cooked Rice Packed in Retort Pouch)

  • 이신영;이상규;변유량;유주현;한병곤
    • 한국식품과학회지
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    • 제13권2호
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    • pp.153-159
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    • 1981
  • Retort pouch 식품의 가열살균에 관한 연구의 일환으로 軍用(군용) 및 야외휴대용(野外携帶用)으로의 활용이 크게 기대되는 미반(米飯)에 대해 미생물학적으로 안전하면서 품질의 손실을 최소로 할 수 있는 적정 가열살균조건을 수증기 공기 혼합계(系) 가견수냉식(加堅水冷式) 살균장치를 이용하여 검토하였다. 두께 $15{\sim}25mm$인 retort pouch 미반(米飯)에 대해 열처리온도 $110{\sim}120^{\circ}C$범위에서 열침투시험을 행한 결과 수증기비(比) 65%이상에서는 열전달속도는 수증기비(比)의 영향을 받지 않았으며 $j_h$값은 $1.11{\sim}1.17$로 두께에 관계없이 거의 일정한 값을 보였고 $f_t$값은 두께에 따라 증가하여 $12.0{\sim}16.5$분이었다. 미생물학적으로 안전한 retort pouch 미반(米飯)의 살균조건은 장기 저장시험결과 $F_0$6.0이상인 것으로 나타났다. 열처리 공정의 C값 및 살균한 미반(米飯)의 가열변색을 검토한 결과 최적 품질보유가 가능한 온도-시간조건은 시료두께 15mm의 경우 $120^{\circ}C$에서 승온 및 하강시간을 포함한 38분이였다.

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Determination of Optimal Storage Condition for Pre-packed Hanwoo Loin

  • Seol, Kuk-Hwan;Park, Tu San;Oh, Mi-Hwa;Park, Beom-Young;Cho, Seong In;Lee, Mooha
    • 한국축산식품학회지
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    • 제33권3호
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    • pp.390-394
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    • 2013
  • The aim of this study was to determine the optimal storage condition of pre-packed Hanwoo beef without freezing. Hanwoo loin was purchased from a local distributor at 48 h after slaughter, then sliced in $1.5{\pm}0.5$ cm thickness, and packed in a polyethylene (PE) tray covered with linear low-density polyethylene (LLDPE) film. The studied factors to set the optimal storage condition were chamber temperature (5, 2.5 and $-1^{\circ}C$ for 14 d), cooling method (direct and indirect cooling system), and ultraviolet (UV) light irradiation for beef surface sterilization (0, 30, 60, and 120 min). The changes of pH, thiobarbituric acid reactive substances (TBARS) and number of aerobic bacteria were measured during storage. Beef samples stored in $-1^{\circ}C$ showed the minimal increasing rate in TBARS and microbial growth. After 15 d of storage, there was no significant difference in pH and TBARS values. However, the microbial population of beef stored in direct type cooling chamber ($4.25{\pm}0.66$ Log CFU/g) was significantly lower than that of beef stored in indirect type chamber ($6.47{\pm}0.08$ Log CFU/g) (p<0.05). After 4 d of storage, 60 or 120 min UV light irradiated beef samples showed significantly lower microbial population, and at 14 d of storage, 60 min UV irradiated beef sample showed significantly lower microbial population ($3.14{\pm}0.43$ Log CFU/g) than control ($4.46{\pm}0.13$ Log CFU/g) (p<0.05). However, TBARS values of 60 or 120 min UV light irradiated beef samples were significantly higher than non-irradiated beef sample after 4 d of storage (p<0.05).

액체배양 방법을 이용한 멸종위기종 복주머니란 종자 무균발아 및 증식 (Propagation of asymbiotically germinated seedlings with liquid culture for endangered lady's slipper orchid (Cypripedium macranthos Sw.))

  • 이정관;허윤선;박상임;박재성;정미진;손성원;서강욱
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2018년도 춘계학술발표회
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    • pp.45-45
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    • 2018
  • We had already reported the successful germination for green pods of purple lady's slipper orchid (Cypripedium macranthos Sw.). The green pod methods is to take immature seeds in green capsules, sterilize the capsule, and take out the sterile seeds. This method, however, needs very critical time of harvest. The critical time of seed harvest changes depending upon the species, condition of the specimen, and climatic influence, and the right time lies between 5 and 12 weeks after fertilization. In this study, the mature seeds were collected after 120-130 days with hand-polination of lady's slipper orchids. Mature seeds are usually dormant and it has to be overcome, either with hormone or storing the seeds near freezing for two or three months to break dormancy. The seeds were first surface sterilized with 70% ethanol and then transferred 1% NaOCl for 10-15 minutes, followed by rinses 3 times with sterilized distilled water. The cypripedium seeds consists of an embryo within a seed coat known as a testa. The testa is water repellent and the seed has a large air space between the embryo and testa so the seed tends to float on water. We had resolved the problems with vacuum pump to soak water into the testa before sterilization. The seeds were placed on liquid or agar solidified germination media. Cultures were incubated at $24{\pm}1^{\circ}C$ in dark. The seeds were germinated in 6-8 weeks in liquid suspension culture (germination percentage over 18%); however, the seeds on agar solidified media took more than 5 months to germinate and the germination percentage less than 5%. The most effective media for liquid culture was 1/4 strength Murashige and Skoog (MS) medium with 50 ml/l coconut water ($4brix^{\circ}$) at pH 5.8.

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HACCP 시스템 적용 학교급식 위생관리 수행수준에 영향을 미치는 요인 - 서울, 경기, 강원, 충청지역을 중심으로 - (Factors Related to Sanitary Management Performance Based on HACCP System in School Foodservice - Seoul, Gyeonggi, Kangwon and Choongchung Areas in Korea -)

  • 김경미;이심열
    • 대한지역사회영양학회지
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    • 제14권6호
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    • pp.817-830
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    • 2009
  • The purpose of this study was to analysis the sanitary management performance based on HACCP system for school foodservice. This study was carried out from September 2008 until December 2008 and is targeted towards schools' dietitians that work at schools with school foodservice. The regional distribution of this research is as follows; 377 schools in Seoul, 648 schools in Gyeonggido, 160 schools in Kangwondo, 438 schools in Choongchungdo equaling 1,623 schools in total. When school foodservices were put through sanitation management achievement level analysis applied by the HACCP system, results displayed that management of temperature (3.96 points), time (4.08 points), and cross-contamination (4.07 points) were all below the average achievement level. HACCP system's achievement level based on the TQM showed that areas for strategy development, leadership, information and analysis had low achievement levels. Achievement levels for CCP are quality check, delivery/distribution process, sterilization/cleansing of food's contact surface. As a result of multiple regression analysis of the factors that influenced sanitation management achievement level of school foodservice HACCP system; sanitary job standard showed 35.6% and CCP achievement levels showed 26.8% explanatory rate. In particular, Kangwondo's number of foodservice provided to per cook was small. Also, the better the processing management was assessed, the higher the sanitary job standard achievement level became resulting to a explanatory rate of 39.5%. Elementary schools showed a higher explanatory rate of 37.0% than middle and high schools. CCP achievement levels in middle and high schools with self-operated foodservice had a 28.0% variable explanatory rate, which was the highest. The better the drainage system, leadership and assessments turned out to be, the higher the CCP achievement levels became. In summary, to revitalize HACCP system that is based on the TQM, it is considered that proper database of HACCP system for school foodservice's sanitation management be constructed and more emphasis should be put on strategy development to improve customers' satisfactory level. In addition, improvements in achievement levels of time, temperature, and cross-contamination for sanitary job standard and CCP achievement level are essential.