好氣性 固定床 生物膜 反應槽의 메디아로 폐칫솔의 利用可能性 檢討에 관한 基礎硏究 : 처리효율을 중심으로

임채영,김정권,성낙창,신남철,김형석,전기일 동아대학교 환경문제연구소 1997 硏究報告 Vol.20 No.1

This study was conducted to evaluate the possibility to apply the waste toothbrush to aerobic fixed biofilm reactor for media. The media used for this research was waste toothbrush (WTB) and Pall-Ring. The feed used for this research was synthetic wastewater which was made at the laboratory. The COD, NH₄^(+)- N and PO₄^(-3)-P removal efficiency variations with the organic loading rate was examined at this research. The conclusions drawn from these experiments are listed below : 1. When the influent COD concentration was respectively 300mg/ℓ, 600mg/ℓ, the COD removal efficiency was decreased with the increase of the organic loading rate and the COD removal efficiency for Pall-Ring was higher than the COD removal efficiency was 0.4~1.9%. 2. When the influent NH₄^(+)-N concentration was respectively 13mg/ℓ (COD 300mg/ℓ), 25mg/ℓ (COD 600mg/ℓ ), the NH₄^(+)-N removal efficiency for Pall-Ring was slightly higher than the NH₄^(+)-N removal efficiency for Wastetooth brush. The difference of NH₄^(+)-N removal efficiency was about 0.5~1.5%. 3. When the influent PO₄^(-3)-P concentration was respectively 7mg/ℓ (COD 300mg/ℓ), 14mg/ℓ (COD 600mg/ℓ ), the PO₄^(-3)-P removal efficiency for Pall-Ring was higher than the PO₄^(-3)-P removal efficiency for Wastetooth brush. The difference of PO₄^(-3)-P removal efficiency was about 1.1~2%. 4. COD, NH₄^(+)-N and PO₄^(-3)-P removal efficiencies show very small difference between Pall-Ring and Wastetooth brush as media. So it was showed that wastetooth brush can be used as media very successfully.

지역사회에서 형성된 사회적 지지와 근로자의 사회심리적 스트레스간의 관련성

임화영,김형수,최영환,장성훈,이건세,정최경희,오원기,최재욱,정춘화 대한산업의학회 2006 대한직업환경의학회지 Vol.18 No.4

Objective: This study was performed to examine the relationship between community-based social support and psychosocial distress in workers. Methods: The study subjects were 596 workers recruited from 11 companies in Chungju city. A structured questionnaire was used to assess sociodemographics, health-related behaviors, job characteristics, job stress, work-based social support, community-based social support and level of psychosocial distress. Results: Hierarchical multiple regression analysis showed that workers with no chronic disease, exercise and sufficient sleep had a higher score of psychosocial distress than those with chronic disease, no exercise, and not enough sleep. Coworker's work-based social support and community-based social support were negatively associated with psychosocial distress. The R square value of total independent variables on psychosocial distress was 0.409, and that of community-based social support on psychosocial distress was 0.052. Conclusion: This study showed that community-based social support served as a protective factor against psychosocial distress in some workers. We recommend the establishment of a worksite stress reduction program in occupational level as well as community-based social support.

항 Vancomycin 내성균성 항생물질을 생산하는 Streptomyces sp.AMLK-335의 배양조건

이기형,임대석,최경희,이경호,김창한,김정환 건국대학교 동물자원연구센터 2000 動物資源硏究誌 Vol.21 No.-

본 연구는 새로운 항 vancomycin 내성균성 항생물질을 개발하기 위하여 실시되었으며, 전국 각지의 토양 시료로부터 분리한 방선균 중 vancomycin 내성균주인 K-98 Enterococcus faecium 642, K-98 Enterococcus faecium 637 균주에 대하여 항생물질을 생산하는 분리균주 AMLK-335를 선정하여 이 균주의 항생물질 생산에 대한 최적 발효 조건을 검토한 결과, 탄소원 첨가로는 glycerol(0.5%), 질소원 첨가로는 yeast extract(0.5%)가 가장 효과적으로 항생물질 생산에 이용되었고, 비타민을 첨가에 따른 항생물질 생산성의 차이는 크게 나타나지 않았으나, calcium pantothenate 첨가시 항균활성이 비교적 높아졌으며, 금속이온의 첨가는 K+, Pb+, Ba²+, NA²+ , Ca²+를 첨가하였을 때는 항생물질의 생산성이 비교적 높아졌으며, 그중 Ca²+ 첨가구가 가장 생산성이 높았으며, Fe²+ , Hg+의 금속이온을 첨가하였을 때는 항생물질 생산성이 감소하였으며, CaCO₃첨가는 비첨가구보다 높은 항생물질 생산성을 보였으나, 첨가량에 따른 영향은 대체적으로 없었다. pH의 변화에 따른 생산성은 전반적으로 pH가 항생 물질 생산에 영향을 미치지 못하였으나, pH 4.5∼6.0 부근에서는 비교적 높은 항생물질 생산성을보였으며, 통기량에 따른 항생물질 생산성은 통기량이 많을수록 항생물질 생산이 좋았다. 한편 배양기간에 따라 항생물질 생산성을 조사한 결과, 5일째에 가장 높은 항생물질 생산성을 나타내었으며, pH의 변화는 배양 초기에 하강하였다가 점차 상승하는 경향을 보였다. This study was carried out for examining antibiotic productivity of the strain Streptomyces sp. AMLK-335 producing anti-VRE antibiotic. According to different condition, the strain was cultured for 4 days at 27℃ and determined cell growth, pH value and antibiotic productivity using disk diffusion method. In the experiment, the strain Streptomyces sp. AMLK-335 was examined various culture conditions which was added 8 carbon sources, 12 nitrogen sources, 8 vitamins and 11 metal ions in each time and controlled concentration of CaCO₃, initial pH and aeration. From the studies of conditions for antibiotic production, antibiotic productivity was the best to use 0.5% glycerol as carbon source and 0.5% yeast extract as nitrogen source. When several vitamins were added to medium, there was little difference in antibiotic productivity. But the addition of calcium pantothenate slightly increased antimicrobial activity. The addition of metal ion, such as K+, Pb+, Ba²+, NA²+ and Ca²+ slightly increased antibiotic productivity except Fe²+ and Hg+. The addition of CaCo₃showed higher than non-addition experiment in antibiotic production, but there wasn't generally influenced at addition concentration. According to pH change, antibiotic productivity was increased at pH 4.5∼6.0, and when there was a lot of aeration, antibiotic productivity was increased.

Determination of Diversity, Distribution and Host Specificity of Korean Laccaria Using Four Approaches

( Hae Jin Cho ),( Ki Hyeong Park ),( Myung Soo Park ),( Yoonhee Cho ),( Ji Seon Kim ),( Chang Wan Seo ),( Seung-yoon Oh ),( Young Woon Lim ) 한국균학회 2021 Mycobiology Vol.49 No.5

The genus Laccaria (Hydnangiaceae, Agaricales) plays an important role in forest ecosystems as an ectomycorrhizal fungus, contributing to nutrient cycles through symbiosis with many types of trees. Though understanding Laccaria diversity and distribution patterns, as well as its association with host plants, is fundamental to constructing a balanced plant diversity and conducting effective forest management, previous studies have not been effective in accurately investigating, as they relied heavily on specimen collection alone. To investigate the true diversity and distribution pattern of Laccaria species and determine their host types, we used four different approaches: specimen-based analysis, open database search (ODS), NGS analysis, and species-specific PCR (SSP). As a result, 14 Laccaria species have been confirmed in Korea. Results regarding the species distribution pattern were different between specimen-based analysis and SSP. However, when both were integrated, the exact distribution pattern of each Laccaria species was determined. In addition, the SSP revealed that many Laccaria species have a wide range of host types. This study shows that using these four different approaches is useful in determining the diversity, distribution, and host of ECM fungi. Furthermore, results obtained for Laccaria will serve as a baseline to help understand the role of ECM fungi in forest management in response to climate change.

PHENYL MERCURIC ACETATE(PMA) 投與動物에 있어서 STAPHYLOCOCCUS AUREUS 靜脈內注射에 의한 腎의 病理組織學的 變化

林昌亨 서울대학교 1968 서울대학교 論文集 Vol.19 No.-

Experimental studies were undertaken on the renal histopathological changes, in Albino rats, caused by staphylococcal infection following the treatment of phenyl mercuric acetate. An acute tubular nephrosis were experimentally induced with a single dose of PMA via oral route and infected with a single injection of coagulase-positive, non-hemolytic Staphylococcus aureus intravenously. Throughout the studies, the gross and histopathological changes in the kidney were observed and the following conclusions were made: 1. In the animals injected with Staphylococcus aureus 1 hour after the administration of PMA, the following changes were observed in the kidney according to the duration: a) After 24 hours, it was revealed that the focal infiltration of inflammatory cells composed mainly of neutrophils was present in the interstitial tissues. b) At 48 hours, moderate severe changes of inflammation were enhanced. In the lumen of lower nephrons and in the foci of inflammatory cell infiltration, the neutrophilic pluggings and the bacterial clumps similar to Staphylococcus aureus morphologically were observed respectively. c) After 3 days, abscesses were observed in the renal medulla. d) After 5 days, inflammatory changes accompanied with necrosis of renal papilla that were resembled to pyelonephritis were observed. e) After 7 days, connective tissue cells began to appear in the inflammatory regions, and many degenerated neutrophils were filled to the renal pelvic cavity. f) After 2 weeks, the lesions of renal papilla were gradually replaced by fibrous

INHIBITORY EFFECTS OF RED GINSENG EXTRACT ON DEVELOPMENT OF PEPSINOGEN 1 DECREASED PYLORIC GLANDS IN RAT STOMACH

Lim, Chang-Hyeong 한국독성학회 1989 Toxicological Research Vol.5 No.2

This study was carried out to investigate the effect of red ginseng extract on development of pepsinogen 1 decrased pyloric glands in experimental stomach carcinogenesis in Sprague-Dawley male rats. Sequential quantitative analyses (by ABC immunohistochemical staining) were made of pepsinogen 1 decreased pyloric glands (PDPG) after treating rats first with a single dose (160 mg/kg) N-methyl-N'-nitrosoguanidine (MNNG) and then with N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) (100ug/ml of drinking water) as a second gastric carcinogen (or promoter).

The incidence and survival of cervical, ovarian, and endometrial cancer in Korea, 1999-2017: Korea Central Cancer Registry

( Hyeong In Ha ),( Ha Kyun Chang ),( Soo Jin Park ),( Jiwon Lim ),( Young-joo Won ),( Myong Cheol Lim ) 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.5

Objective The three major gynecologic cancers are cervical, endometrial, and ovarian cancer. This study aimed to describe the 19-year trends and survival rates in cervical, endometrial, and ovarian cancer in a Korean female population. Methods We searched the Korea Central Cancer Registry to identify patients with gynecologic cancer between 1999 and 2017. Age-standardized rates and annual percent changes were calculated. The relative survival rate (RSR) was reported by histology, age, and stage for each gynecological cancer. Results The total number of cervical, endometrial, primary peritoneal, ovarian epithelial, fallopian tube (POFT) cancer was 134,863, with the number of cases increasing every year: 6,077 in 1999 to 8,011 in 2017. The incidence of cervical cancer has decreased; however, that of POFT and endometrial cancer has increased. The 5-year RSR of cervical, POFT, and endometrial cancer was reported to be 80.8%, 61.4%, and 88.1%, respectively. In the case of cervical cancer, squamous cell carcinoma showed better survival than other histology (82.8% vs. 73.5%). Furthermore, in the case of endometrial cancer, endometrioid histology had substantially better 5-year RSR than the others (93.2% vs. 76.5%). Contrastingly, in the case of ovarian cancer, serous carcinoma had worse 5-year RSR than other types of histology. Conclusion The incidence rates for gynecologic cancers increased from 2005 to 2017, with an annual increase of 2.76 per year until 2017. Endometrial cancer had the highest RSR, while ovarian cancer had the lowest. Active cancer screening and the introduction of effective treatments might have contributed to the improved RSRs of gynecologic cancers.

[P3-108] Disinfection Effects of Direct Electrolysis on Sap and Quality Changes During Storage

Chang Hyeon Lee,Jin Soek Choi,Jin Tae Kim,Jin Woo Nho,Seon Hyeong Lim,Sun Hee Lee,Heon Sang Jeong,Chang Seob Shin 한국식품영양과학회 2009 한국식품영양과학회 학술대회발표집 Vol.2009 No.11

CNG 혼소율 변화에 따른 디젤엔진의 성능 및 연소 특성에 관한 연구

장형준(Hyeong-Jun Jang),이선엽(Sun-Youp Lee),김창기(Chang-Gi Kim),조정권(Jeong-Kwon Cho),임종한(Jong-Han Lim),윤준규(Jun-Kyu Yoon) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.5

전 세계적으로 천연가스 시장에서는 천연가스의 저열량화 추세로 뚜렷하게 변화되고 있다. 이러한 추세는 국내의 천연가스 열량기준에 변화를 가져왔으며, 낮은 열량의 천연가스 도입으로 인해 현재 사용되고 있는 가스기기의 성능에도 변화가 있을 것으로 예측된다. 따라서 본 연구에서는 혼소엔진의 연소특성을 파악하기 위해 CNG 혼소율 변화를 이용하여 열효율, 도시평균유효압력 변동계수 및 열방출 특성을 고찰하였다. CNG 혼소율은 투입되는 연료의 총합 대비 공급되는 천연가스연료의 에너지로 계산하여 천연가스연료가 디젤연료를 대체하는 비율로 정의하였다. 엔진 실험조건으로는 공급되는 천연가스의 발열량은 10,400 ㎉/N㎥이며, 1800 rpm/500 N·m의 엔진 운전조건에서 디젤연료의 분사시기는 BTDC 16°CA, 분사압력은 85 ㎫로 설정하여 엔진의 성능 및 연소 실험을 진행하였다. 엔진 실험결과로 CNG 혼소율이 변화함에 따라 공급되는 디젤 연료량 역시 변화하고, CNG 혼소율이 증가할수록 디젤 연료량이 감소함으로써 점화에너지가 줄어들어 점화지연기간이 길어지는 연소특성을 나타내며, 이로 인해 엔진의 열효율과 출력도 감소하는 경향을 보였다. 그러나 연소안정성은 5% 미만으로 안정적인 엔진의 연소상태를 보여 실험의 신뢰성을 확보할 수 있었다. In the international natural gas market, natural gas has markedly low calories. The domestic calories standard of natural gas was changed and the performance and efficiency of many industrial machines using natural gas were affected because of low caloric natural gas. Therefore, in this study, a dual fuel engine fueled with natural gas and diesel was tested to examine the effects of the CNG substitution rate on the combustion characteristics, such as thermal efficiency, COVimep and heat release rate. The CNG substitution rate was defined as the ratio of CNG instead of diesel, which was calculated as the total energy. The conditions of the tested engine were fixed 1800 rpm/500 N·m. In addition, diesel fuel was injected at 16°CA BTDC and the fuel pressure was fixed at 85 ㎫; the lower heating value of CNG was 10,400 ㎉/N㎥. The results of the engine test showed that the amount of diesel fuel was changed according to the CNG substitution rate. Therefore, when the substitution rate was increased, the amount of diesel fuel was decreased, which affected the energy for ignition. In addition, the ignition delay duration was increased, which affected the thermal efficiency and torque. On the other hand, the COVimep was less than 5% and a stable combustion state of the engine was shown.

1?F-FDG PET SUVmax as an indicator of histopathologic response after neoadjuvant chemotherapy in extremity osteosarcoma.

Kong, Chang-Bae,Byun, Byung Hyun,Lim, Ilhan,Choi, Chang Woon,Lim, Sang Moo,Song, Won Seok,Cho, Wan Hyeong,Jeon, Dae-Geun,Koh, Jae-Soo,Yoo, Ji Young,Lee, Soo-Yong Springer-Verlag 2013 European journal of nuclear medicine and molecular Vol.40 No.5

<P>This study evaluated the usefulness of the maximum standardized uptake value (SUVmax) as a measure of histologic response to neoadjuvant chemotherapy in patients with extremity osteosarcoma. The correlation between [(18)?F]FDG PET SUVmax values and histologic response to preoperative chemotherapy was also assessed prospectively using PET/MRI.</P>