함마의 재질이 규석의 분쇄에 미치는 영향

이재장,장상건,장광택,박종력 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

In Kwangjin industrial company, mill is operating for the foundry sand production at the rate of 25t/hr from quartzite. Foundry sands fall into four distinct categories: silica sand, lake sand, bank sand, and natural molding sand. Silica sand is a general term used to describe crushed, washed, graded, dried, and cooled clay-free sands. This study was conducted for the investigation of the foundry sand productivity and the life span of the hammer according to the material quality. The life time of hammer from several manufacturer were compared in order to find out the grinding efficiency of the various hammer material. In the result of tests, the life time of high-Mn hammer was 10.5 hours while that of high-Cr was 19.5 hours. The life time in case of typical worn shape hammers was about 12 hours and the average time of a blowhole hammer was about 6.5 hours.

Shaphylococcus enterotoxin B와 lipopolysaccharide를 작용시킨 사람 섬유아 세포에서 생성된 Transforming Growth Factor-β₁의 정량적 분석

이성근,김광혁,김욱규,김종렬,정인교,양동규 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.2

TGF-β1 is a potent chemotactic factor for inflammatory cells and fibroblasts. It also stimulates the celluar source and components of extracellular matrix and the production of proteinase inhibitors. Collectively, these biologic activities lead to the accumulation and stabilization of the nascent matrix, which is vital to infection control. The objective of this study is to investigate production of TGF-β in vitro fibroblast culture in the presence of Staphylococcus enterotoxin B(SEB) and/or lipopolysaccharide(LPS) and to elucidate the role of TGF-β1 which may be responsible for infection control. The fibroblasts were originated from gingiva and facial dermis in 26 year-old male patient. In the presence of LPS(0.01㎍, 0.1㎍, 1.0㎍), SEB(0.01㎍, 0.l㎍, 1.0㎍) respectively, cells(5×103ml) were cultivated in vitro. At 1, 3, and 5 days after incubation, cells were counted. Also, cells(2.5×105ml) were cultivated in EMEM with LPS(0.01, 0.1 and 1.0㎍), SEB(0.01, 0.1 and 1.0㎍) respectively and LPS(0.1㎍) and SEB (0.1㎍) in combination for 24,48, and 72 hours respectively. Culture supernatants were harvested at 1, 2, and 3 days after incubation period and triplicate culture supernatants were pooled and TGF-β1 was assayed in duplicate. The results were as follows. 1.In gingival fibroblast induced with SEB and LPS respectively or in combination, the suppression of cell Proliferation occurred very significantly since 3 days after incubation, compared with the control and the production of TGF-β1 occurred very significantly at 1 day after incubation, compared with the control. 2.In facial dermal fibroblast induced with SEB and LPS respectively or in combination. the suppression of cell proliferation occurred very significantly at 1 day after incubation, compared with the control. In SEB exposure, the production of TGF-β1 was decreased very significantly at 1 day after incubation, compared with the control. However, in LPS, SEB and LPS exposure, the production of TGF-β1 was increased very significantly at 1 day after incubation, compared with the control. In conclusion, the concentration of bacterial toxins and the incubation period correlated with cell proliferation and production of TGF-β1 very significantly. The gingival and facial dermal fibroblasts have different phenotype each other The orchestrated understanding of fibroblast proliferation and TGF-β1 production play an important part in host defense against the bacterial Infection and may prevent tissue necrosis such as necrotizing fasciitis and life-threatening syndrome such as multiple organ failure.

복숭아의 재배 및 저장기간 중 Procymidone, Chlorpyrifos 및 Cypermethrin의 잔류량 변화

이용재,고광용,원동준,길근환,이규승 한국환경농학회 2003 한국환경농학회지 Vol.22 No.3

복숭아의 생산단계에서 잔류허용 기준과 최종 소비단계에서의 잔류양상 평가자료로 활용하기 위하여 복숭아에서의 procymidone, chlorpyrifos 및 cypermethrin의 포장상태에서와 실온(20°C) 및 저온(4°C) 저장시 잔류양상을 알아보았다. Procymidone의 포장상태에서의 반감기는 표준량 3.1, 배량 3.4일로 나타났고, chlorpyrifos는 포장상태에서 포준량 7.2, 배량 5.8일로 나타났으며, cypermethrin은 표준 10.1, 배량 14.4일로 나타났다. 약제 살포 후 초기 부착량이 MRL 이하로 내려갈 때까지의 시간을 계산해 본 결과 배량으로 살포 할 경우 procymidone과 chlorpyrifos는 안전사용기준 보다 시간이 오래 걸렸지만, 표준량으로 사용할 경우 별다른 문제가 없는 것으로 나타났다. 저장기간 중의 procymidone, chlorpyrifos, cypermethrin의 반감일수는 20°C에서 4.6, 10.2, 12.9일 이며, 4°C에서는 16.1, 14.3, 13.1일로 저온에서의 반감기가 실온에서보다 더 긴 것을 알 수 있었다. 한편 세척방법에 의한 잔류농약의 제거율은 수돗물에서는 최고 procymidone 82.9%, chlorpyrifos 27.0%, cypermethrin 24.0%로 나타났고, 세제를 사용 할 경우 procymidone 88.8%, chlorpyrifos 59.0%, cypermethrin 59.4%의 제거율을 보였다. The residue patterns of procymidone, chlorpyrifos and cypermethrin in peaches were examined. The pesticides were sprayed at 15 days before harvest and then were determined the residue at 0, 1, 2, 3, 5, 7, 10 and 15 days after pesticide application and calculated their DT_(50). Also, the degradation patterns at 4℃ and 20℃ during storage period were compared. Biological half-lives of procymidone, chlorpyrifos and cypermethrin in peaches during the cultivation period were 3.1, 7.2 and 10.4 days, respectively. The biological half-life of procymidone was shorter than the others. During the storage period, half-lives of procymidone, chlorpyrifos and cypermethrin were 16.0, 14.3 and 13.1 days at 4 C and 4.6, 10.2 and 12.9 days at 20℃, resp ectively. The degradation rates of these three pesticides in storage period were slower than them in cultivation period. Removal rates were 22.2--82.9% by tap water, and 12.5∼88.8% by detergent solution.

세포질내 정자주입법(ICSI)에 있어서 정자흡입 및 난자내 주입방법에 관한 연구

이택후,김항진,송건호,김대근,전상식,박윤규,서태광,전병균,류은경,이은숙,문진수,김광철 경북대학교 의학연구소 2000 경북대학교병원의학연구소논문집 Vol.4 No.1

Study on Method of Sperm Aspiration and Injection into an Oocyte in Intracytoplasmic Sperm Injection(ICSI) Immobilization of spermatozoa prior to intracytoplasmic sperm iniection(ICSI) sometimes results in crooked tail and this makes it difficult to aspirate sperm into an injection pipette tail first. Head-first sperm aspiration into an injection pipette avoid this problem due to the bigger size of the sperm head. The effect of head or tail-first sperm injection into an oocyte on fertilization cleavage, percentage of grade I embryos and development to blastocyst stage in ICSI program has been studied. A single living immobilized spermatozoa from oligoasthenozoospermic patient was injected into an oocyte head-first or tail-first according to the treatment. Eighteen hours after microinjection, oocytes ware inspected for survival and fertilization Fertilized oocytes with two pronuclei were cultured in 30μl drop of mHTF supplemented with 10% heat-inactivated follicular fluid(FF) at 37℃. On day 2. embryo transfer was performed with cleaved embryos. The remaining 2-8 cell stage embryos were co-cultured with BRL cells in mHTF + 10% FF for 72 hours and the developmental stage was observed. The data were analyzed by Analysis of Variance. A total of 164 oocytes from 36 cycles were assigned to earth treatment and ICSI was performed(88 head-first, tail-first). The rates of normal fertilization were 81.8% and 76.3% for head-first and tail-first, respectively. Of the fertilized oocytes, the percentage of cleaved embryos and the percentage of grade 1 embryo among cleaved embryos were 88.9% and 68.8%, 93.1% and 74.1% for head-first and tail-first, respectively. Of the 2-8 cell embryos cultured, 44.4%(16/36) and 50.0%(10/20) for head first and tail first, respectively developed to blastocyst stage. There were no differences in fertilization, cleavage, rates of grade 1 embryos, and development to blastocyst stage. In conclusion, head-first or tail-first sperm injection into an oocyte in ICSI program does not affect fertilization and subsequent embryo development to blastocyst stage in vitro.

다랑 토혈 후 발생한 뇌경색으로 인하여 간질중첩증을 보인 간성 뇌중 1예

오형근,정두신,이경복,양광익,박형국 순천향의학연구소 2007 Journal of Soonchunhyang Medical Science Vol.13 No.1

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상완골 간부 골절 불유합의 금속판과 자가골 이식에 의한 치료 결과

이광현,이성필,김형종,이봉근,김주학 대한골절학회 2004 대한골절학회지 Vol.17 No.2

광학활성 B-Alkoxy-9broabicyclo[3.3.1]nonane-Potassium Hydride 환원계에 의한 라세미 에폭시화물의 분할

李光雨,孔亨根,車震淳 嶺南大學校附設 基礎科學硏究所 1986 基礎科學硏究 Vol.6 No.-

In this study, chiral B-alkoxy-9-borabicyclo[3.3.1]nonane-potassium hydride systems were applied to the resolution of representative racemic epoxides, namely 1,2-epoxybutane, 1,2-epoxyoctane and styrene oxide. Chiral B-alkoxy-9-BBN systems were synthesized from the reaction of 9-BBN with (-)-isopinocampheol and (-)-cis-myrtanol, respectively. The resolution of 2 equiv of racemic epoxide was carried out with 1 equiv of the reducing system at 0℃. Thus, the 1 equiv of epoxide was reduced to the alcohol, remaining the other 1 equiv of epoxide intact. The resolving ability of these systems in terms of optical purity of the alcohol appeared to be 25-40% in the case of aliphatic epoxide and 9-12% in the case of styrene oxide. The absolute configuration of the alcohols is consistent with (R)-(-)-aliphatic alcohol and (S)-(-)-1-phenylethanol.

양측성 전정장애 환자들의 전정기능검사

이근호,김재일,정필섭,전범석,이광우 대한신경과학회 1996 대한신경과학회지 Vol.14 No.4

가열식품중의 Acrylamide : 검출농도, 생성기작, 그리고 독성을 중심으로 Detection Level, Formation Mechanism, and Toxicity of Acrylamide

이광근 한국산업식품공학회 2003 산업 식품공학 Vol.7 No.2

Since the Swedish National Administration (NFA) and researchers from Stockhorm University announced that acrylamide, a toxic potentially cancer-causing chemical, was formed in many types of food cooked at high temperature in April 2002, there have been a lot of international meetings and researches dealing with formation mechanism and toxicity of arylamide. It is hard to surely figure out the mechanism and toxicity of acrylamide at present time. This article deals with the detection levels in various foods, toxicity and formation mechanism o acrylamide. Acrylamide formation during food processing and cooking was confirmed by researchers of UK, Sweden, Switzerland and United States. They insisted that acrylamide in heated foods was formed by Maillard reaction between asparagine and glucose during cooking and food processing. It is well-know that heating time and temperature are significant factors for acrylamide formation in food processing. Regarding to the toxicity of acrylamide we need more experimental data to conclude its toxicity for humans. So far there is no credible evidence that acrylamide in foods poses a human cancer risk. Though acrylamide increased the incidnece of tumors in the high-dose rodent test, it is difficult to relate its toxicity to the human carcinogens. In the future, more accurate analysis of acrylamide in various foods, the human toxicity, and reduction study based on the formation mechanism should be investigated to prevent consumer's confusion.

의료정책에 따른 종합병원의 로비공간 변화

한광호,함욱,박창근,이낙운 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.B

The purpose of this study are observing changing direction of lobby space that happen by change of medical environment investigating lobby space of General Hospital by our country's medical policy change time and supply pabulum that need in forward Hospital Architecture planning. Results of this study are as follows ; Since Whole National Insurance enforcement from 1993 to 1995, form of general hospital lobby is form that outpatient entrance and inpatient entrance are detached. And lobby function divided to waiting space for medication, requisition space and also that is appearing being detached with rest space for user. ntil 1999 since 1996 that is since Medical Treatment Information System construction, the biggest characteristic of General Hospital lobby form is making Hospital Street itself do improving efficiency of flow planning being included in lobby