Sn-3.5Ag 땝납의 Zn첨가가 기계적 특성에 미치는 영향

이도재 ( Lee Do Jae ),이광민 ( Lee Gwang Min ),이경구 ( Lee Gyeong Gu ),오태욱 ( O Tae Ug ),백대화 ( Baeg Dae Hwa ) 한국주조공학회 2003 한국주조공학회지 Vol.23 No.6

N/A Effects of Zn concentration on the mechanical properties of Sn-3.5Ag solder were studied, and compared to those of Sn-40Pb alloy which is widely used currently in electronics industry. Aging treatments were performed at 100 and 150 for up to 120days and then were examined changes of microstructure by optical microscopy, SEM and EDS. Sn-3.5Ag solder was loaded to failure at cross head speed of 0.3 mm. min-1 to measure strength and elongation. Aging treatment changed more or less the tensile properties of the solder itself. In short, Sn-Ag base alloy showed decrease in tensile strength and increase in elongation with prolonged agig time. Sn-3.5Ag alloy showed more sensitive changes in tensile properties than Sn-3.5Ag-1Zn alloy by aging. On the other hand, Sn-40Pb alloy showed decreasing tendances in both tensile strength and elongation by aging.

Low Molecular Weight Polyethylenimine-Mitochondrial Leader Peptide Conjugate for DNA Delivery to Mitochondria

Choi, Joon-Sig,Choi, Min-Ji,Go, Gyeong-Su,Rhee, Byoung-Doo,KimPak, Young-Mi,Bang, In-Seok,Lee, Min-Hyung Korean Chemical Society 2006 Bulletin of the Korean Chemical Society Vol.27 No.9

It has been found that a number of diseases are associated with mutations in the mitochondrial DNA. Therapeutic gene delivery to mitochondria has been suggested as a clinical option for these diseases. In this study, we developed a gene carrier to mitochondria by the conjugation of mitochondrial leader peptide (LP) to polyethylenimine (PEI). Mitochondrial LP conjugated PEI (PEI-LP) was synthesized with low molecular weight PEI (2,000 Da, PEI2K). Gel retardation assay showed that PEI2K-LP formed complexes at a 1.0/1 weight ratio. In addition, PEI2K-LP protected DNA from the enzymatic degradation for at least 60 min, while naked DNA was completely degraded within 20 min. PEI2K-LP was compared with LP conjugated high molecular weight PEI (25,000 Da, PEI25K) in terms of toxicity and delivery efficiency. MTT assay showed that PEI2K-LP had much lower cytotoxicity than PEI25K-LP to 293 cells. In addition, cell-free DNA delivery assay showed that PEI2K-LP delivered more DNA to mitochondria at a 1.8/1 weight ratio than naked DNA or PEI. This result suggests that PEI2K-LP may be useful for the development of mitochondrial gene therapy system with lower cytotoxicity.

Ag-TiO₂ 광촉매 공정을 이용한 Fulvic acid의 제거

이병헌 ( Byung-hun Lee ),김민경 ( Min-gyeong Kim ) 한국수처리학회 2017 한국수처리학회지 Vol.25 No.1

This study is to remove fulvic acid of natural organic matters(NOMs) that existed in water and polluted in the water system. Fulvic acids show a high reactivity towards chlorine and make trihalomethanes in water treatment. The optimum conditions for the removal of natural organic matters were investigated using photocatalytic oxidation, which is and advanced oxidation process. For the more effective photocatalytic reaction than the conventional photocatalytic reaction, Ag was added and the experiment was conducted. Response surface methodology (RSM) was used to find the appropriate amount of Ag injection. Fulvic acid was selected as Natural Organic Matter(NOM). TiO₂ was fixed to the reactor at 300 g/L and a UV lamp with a wavelength of 254 + 185 nm was used in the experiment. Experiments were conducted under the conditions of Ag of 0.15 - 5.8 g / L, reaction time of 10 - 70 min, and irradiation density of 9.5 - 13.7 W / L. Experimental results showed that the optimum removal rate was Ag 3.5 g/L, irradiation density 13 W/L and reaction time 50 min.

외과계 집중치료실에서 입원한 환자에서 APACHE II score의 의의

이영재,이영준,박순태,하우송,정민화,권수인,조영현,권진용,최상경,손신 대한외상학회 1997 大韓外傷學會誌 Vol.10 No.1

This study attempts to evaluate the prognostic value of the APACHE II scoring system in patients of surgical intensive care unit(SICU) and to examine its usefullness in stratifying these patients according to their surgical risk and as a potential aid in making rational and objective treatment decision. The records of 161 patients admitted to the Department of Surgery, Gyeong-Sang National University Hospital between Jan. 1991 and Dec. l995 were reviewed. 1) Of a total of 161 patients, 87 were male, 74 were female, and male to female ratio was 1.71: 1. 2) This group was seen most commonly in the age group of 55-64 which occupied 30.3% of entire group. 3) The distribution of patients according to the etiology were 74 patients(46%) in trauma, 61 patients(37%) iin postop-complication, 26 patients(9%) in others. 4) The distribution of patients according to the APACHE II scores was 9 to 29 point in adm. Day and the most patients was located between 10 and 14 of 62 patient(39%). 5) The length of hospitalization was 9 days in survived patients and 8 days in non-survived patients. The length of hospitalization of 77% of patients in this study was below 10 days. 6) The death rate was 45.45%(73 patient), this patients according to APACHE II scores was 13 to 29, median 19.2 in adm. Day, the most patients was located 20 to 24(20%). Non of the survived patients had the APACHE II score of above 20 points, but all recovered patients were below 13 points. 7) The median APACHE II score in survived patients was 10.52 point at adm. Day and 6.55 point at 5 days after admission. And non-survived patients was 20.25 point at adm. Day and 30.48 point 5 days after admission(p$lt;0.001). 8) Among the patients with low APACHE II score (below 14 points), there was no mortality. But, there was mortality with APACHE II score of above l5 points. We conclude that APACHE II scoring system is useful in measuring the severity of acute disease and predicting the outcome.

딸기 와인 개발을 위한 최적 발효 조건

김민기, 박미성, 엄은경, 조은혜, 이종수 배재대학교 자연과학연구소 2016 自然科學論文集 Vol.27 No.1

Optimal fermentation condition for development of new strawberry wine were investigated. Commercial yeast, Fermivin was good for brewing of strawberry wine and its optimal addition concentration was also 1%. Maximal ethanol content of strawberry wine was obtained when raw strawberry juice(24 brix) was fermented by 1% Fermivin at 25℃ for 7 days and its antioxidant activity was 78.5%. 새로운 딸기 와인을 개발하기 위한 최적 발효조건을 연구하였다. 시판효모인 페미빈이 딸기와인 제조에 제일 좋았고 1%가 최적 첨가 농도이었다. 딸기와인의 최대 에탄올 생성량은 생딸기주스 (24brix)를 1% 페미빈으로 25℃에서 7일 발효시켰을 때 얻어졌고 이 발효액의 항산화활성은 78.5% 이었다.

컴퓨터 작업 시 의자 등받이 위치가 근육 활성도에 미치는 영향

김민우,변승진,이경은,정소영,조주영,최원자,최찬양,김경 대구대학교 특수교육재활과학연구소 2011 再活科學硏究 Vol.29 No.1

이 연구는 컴퓨터 작업시 의자 등받이 위치가 근육활성도에 미치는 영향을 알아보기 위해 36명의 근골격에 문제가 없는 성인 남녀가 참가하였으며 대상자들은 등받이가 뒤에 있는 의자와 등받이가 없는 의자, 등받이가 앞에 있는 우리들 의자를 무작위로 배정하고 동일한 컴퓨터 작업을 실시하게 하였다. 실험 중, 표면근전도기를 사용하여 의자에 따른 위등세모근, 머리널판근 그리고 척주세움근의 근활성도 변화를 측정하였다. 이 연구의 결과를 종합해보면 등받이가 앞에 있는 의자는 허리 근육의 부담을 줄이지만 목근육에 부담이 늘어나고 등받이가 뒤에 있는 의자와 없는 의자는 허리근육에는 다소 무리가 가지만 목근육에는 부담이 덜하다는 것을 알 수 있었다. 이러한 결과로 환자의 증상에 다라 컴퓨터 작업을 하는 동안 의자 등받이의 위치를 조절하여 치료에 도움이 될 수 있다고 생각되어진다. Objective : In this study, we checked and observed people's change of body muscle and muscle activity who do computer work on different chairs. We set three kind of chairs which one is a stool and another one is the back is fixed, and the other one is the back is fixed in front of chair. Subject : Accounting for 36 health men and women, we divided these people to 3 groups and put them on the three cases(position 1, position 2, position 3). We measured muscle activity of upper trapezius, Splenius Cervics, Erector Spinae from the groups by using surface electromyogram system. Methods : The standard of the electromyogram was 'reference voluntary contraction', and we carried out 'one way anova' to compare muscle activity of three groups. Results : In position 1, reference voluntary contraction of upper trapezius muscle activity was 123.2821%, Splenius Cervics was 141.7526%, and Erector Spinae was 254.5233%. In position 2, reference voluntary contraction of upper trapezius muscle activity was 132.9395%, Splenius Cervics was 141.7526%, and Erector Spinae was 246.6540%. In position 3, reference voluntary contraction of upper trapezius muscle activity was 190.6487%, Splenius Cervics was 270.2332%, and Erector Spinae was 182.1021%. Both upper trapezius and Splenius Cervics muscle activity of position 3 group was higher than the others groups. In position 1 group, Erector Spinae muscle activity was hight than the other groups. And either was position 2 group's(p<0.05). Conclusion : Therefore the chair which is the back is fixed in front is more comfortable for waist muscle but it's not good for neck. And the other chairs are better in waist muscle but not in neck muscle. So far, when we do a computer work, it's prefer to sit on the group 1&2's chairs to reduce neck muscle's stress and sit on group 3's chair to reduce waist muscle's stress.

환자안전 인식 향상을 위한 의과대학생 대상 환자안전 역할극 교육의 효과

이원,표지희,장승경,최은영,옥민수,조민우,이상일 건강보험심사평가원 2021 HIRA RESEARCH Vol.1 No.1

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에탄올 생산 향상을 위한 발효저해물질 제거와 리그닌 유래 발효저해물질이 에탄올 발효에 미치는 영향

엄민 ( Min Um ),신경진 ( Gyeong-jin Shin ),이재원 ( Jae-won Lee ) 한국목재공학회 2016 목재공학 Vol.44 No.3

본 연구에서는 옥살산 전처리 바이오매스의 액상가수분해산물에 포함된 발효저해물질을 전기투석과 XAD 수지 처리하여 제거한 후 에탄올을 생산하였다. 전기투석 과정에서 아세트산은 대부분 제거되었으며(95.6%), 비이온성 발효저해물질(Total phenolic compound: TPC, 5-hydroxymethyl furfural: HMF, furfural)은 XAD 수지 처리에 의해 효과적으로 제거되었다. 전기투석과 XAD 수지 처리된 액상가수분해산물로 발효를 수행한 결과 XAD 수지의 침지시간이 짧을수록 에탄올 생산이 향상되었다. 최대 에탄올 생산은 발효 72시간 후 6.16 g/ℓ로 전기투석 후 액상가수분해산물을 XAD-4 수지에서 5분 침지하였을 때 나타났다. 리그닌 유래 발효저해물질 중 syringaldehyde는 저농도(1 mM, 2 mM)에서 에탄올 생산을 향상시켰으며 5 mM에서는 발효에 부정적인 영향을 주었다. 리그닌 유래 발효저해물질의 시너지효과를 확인하고자 합성배지로 발효를 수행하였으며, Syringaldehyde (1 mM)와 ferulic acid (1 mM) 합성배지를 이용하여 발효를 수행한 결과 syringaldehyde보다 ferulic acid의 영향으로 에탄올 생산이 감소했다. In this study, ethanol was produced from a biomass hydrolysate that had been treated by electrodialysis (ED) and Amberlite XAD resin to remove fermentation inhibitors. Most of the acetic acid (95.6%) was removed during the ED process. Non-ionizable compounds such as total phenolic compounds, 5-hydroxymethyl furfural, and furfural were effectively removed by the XAD resin treatment. Ethanol production was improved when the ED-treated hydrolysate was treated with XAD-4 resin for a short reaction time. The highest ethanol production from ED-treated hydrolysate was 6.16 g/ℓ (after 72 h of fermentation) when the treatment with XAD-4 resin was for 5 min. Among the ligninderived fermentation inhibitors tested, syringaldehyde in low concentrations (1 and 2 mM) in the hydrolysate increased ethanol production, whereas a high concentration (5 mM) inhibited the ethanol production process. A synthetic medium containing syringaldehyde and ferulic acid was prepared to investigate the synergistic effect of inhibitors on ethanol fermentation. Ethanol production decreased in the mixture of 1 mM syringaldehyde and 1 mM ferulic acid, implying that the effect of ferulic acid on ethanol fermentation is comparable to that of syringaldehyde.

경남지역에서 분리한 Salmonella Enteritidis의 항생제 감수성 검사 및 random amplification polymorphic DNA (RAPD)-PCR을 이용한 유전형 분석

김은경 ( Eun-gyeong Kim ),김민경 ( Min-kyung Kim ),권현애 ( Hyun-ae Kwon ),윤도경 ( Do-kyung Youn ),구정헌 ( Jeong-heon Koo ),박소연 ( So-yeon Park ),이희근 ( Hui-geun Lee ),조명희 ( Myeong-hui Jo ),하도윤 ( Do-yun Hah ),김철호 ( 한국동물위생학회(구 한국가축위생학회) 2018 韓國家畜衛生學會誌 Vol.41 No.3

Salmonella Enteritidis (S. Enteritidis) are found in animals, humans, and environment. In addition, S. Enteritidis draws attention to the public health concerns due to carriage of antibiotic resistance traits. For these reasons, the prevalence and antibiotic resistance patterns of S. Enteritidis are significant issues with regard to public health. To address this issues, a total of 24 strains of S. Enteritidis from 164 samples collected from several slaughterhouses in Gyeong-Nam province in order for antibiotic resistance profiles. Subsequently, we characterized the genotyping by random amplification polymorphic DNA (RAPD)-PCR. As a result, very high level of resistance to protein synthesis inhibition antibiotics and most isolates were susceptible to others. Six random primers were used for RAPD-PCR to reveal genotypes of S. Enteritidis isolates. One of the primer, P1245, generated 147 distinct RAPD-PCR fragments ranging from 400∼3000 bp. The number of RAPD-PCR products ranged from 4 to 8 for this primer. The RAPD-PCR fragments could be placed these strains into 3 subgroups and 2 classes by UPGMA cluster analysis. Interestingly, several S. Enteritidis that isolated from different slaughterhouses showed same genotype. These results showed only limited genetic variation among the isolates, those were grouped into a few different patterns of antibiotic resistance.

하악골 절제술후 재이식된 돌결자가골 재이식 : 치험 3례

김 식,김수관,김운규,김수민,류종희,이준길,조경안,김수흥,정태영,여환호 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.2

We described three cases of immediate reimplantation of a frozen-thawed autogenous mandible composed of a mixture of iliac bone, marrow, and particulate hydroxyapatite in tumors of the mandible. Acceptable outcomes were obtained in three patients who underwent immediate autogenous mandibular graft reconstruction. The conditions leading to successful outcome of the procedure are also discussed. Reimplantation of frozen autogenous lesioned mandible was performed in three patients with mandibular tumors. Two reimplanted grafts survived without complications following surgery. One case had postoperative infection that resolved with appropriate antibiotic treatment. There were no recurrences of the primary lesions. Satisfactory facial contour after surgery was achieved. These results are most promising, and we believe that, with further refinement, this technique will offer a new and acceptable modality for facial reconstruction in patients with cancer.