Reduction of Bacillus cereus Contamination in Biofilms on Stainless Steel Surfaces by Application of Sanitizers and Commercial Detergent

Lee, Min-Jeong,Ha, Ji-Hyoung,Kim, Yong-Su,Ryu, Jee-Hoon,Ha, Sang-Do The Korean Society for Applied Biological Chemistr 2010 Applied Biological Chemistry (Appl Biol Chem) Vol.53 No.1

We established the effectiveness of a washing, detergent and sanitizer treatments for reducing Bacillus cereus (B. cereus) contamination in biofilms on stainless steel surfaces. A water treatment did not affect biofilms and chlorine treatments at 200 ppm for 10 min and 300 ppm for 5 min, iodophor at 200 ppm for 10 min, and QAC at 400 ppm for 10 min were used to eliminate all B. cereus cells. B. cereus cells after detergent treatment were eliminated by chlorine at 100 ppm for 10 min, 200 ppm for 5 min, and 300 ppm for 3 min, and with iodophor at 100 ppm for 10 min and 200 ppm for 10 min, and QAC at 400 ppm for 10 min.

Corrosion Behavior of Inconel X-750 for Carbon Anode Oxide Reduction Application

Jeon, Min Ku,Kim, Sung-Wook,Lee, Sang-Kwon,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of the Inconel X-750 alloy was investigated for its potential application under a Cl₂-O₂ mixed gas flow in an Ar atmosphere. The corrosion rate was found to be negligible at temperatures up to 400℃ under a flow rate of 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar, whereas an exponential increase was observed in the corrosion rate at temperatures greater than 500℃. The suppression of the corrosion reaction due to the presence of O₂ was verified experimentally at flow rates of 30 mL·min^-1 Cl₂ (4.96 g·m^-2·h^-1), 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ (2.02 g·m^-2 ·h^-1), and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ (1.34 g·m^-2·h^-1) under a constant Ar flow rate of 170 mL·min^-1 at 600℃ for 8 h. The surface morphology analysis results revealed that porous surfaces with tunnel-type holes were produced under the Cl₂-O₂ mixed-gas condition. Furthermore, the effects of the Cl₂ flow rate on the corrosion rate were investigated, indicating that its impact was negligible within the range of 5-30 mL·min^-1 Cl₂ at 600℃.

수학자 이상설이 소개한 근대자연과학: <식물학(植物學)>

박영민 ( Young Min Park ),김채식 ( Chae Sik Kim ),이상구 ( Sang Gu Lee ),이재화 ( Jae Hwa Lee ) 한국수학교육학회 2011 수학교육논문집 Vol.25 No.2

본 원고는 2004년 과학사학자 박성래 교수가 독립 운동가이자 한국 근대 수학교육의 아버지로 부르기 시작한 보재 이상설(李相卨, 1870-1917)이 자연과학에 기여한 내용을 다루고 있다. 한국수학사학회지 2009년 11월 호에 자세히 소개된 〈數理〉를 쓴 시기를 전후하여, 같은 시기에 이상설이 붓으로 쓴 것으로 여겨지는 〈植物學>(이상설, 1899)은 총 4면의 초록 필사본이며, 그 대본(臺本)은 〈植物學啓蒙〉 (Edkins, 1886)으로 영국의 Joseph Edkins(艾約瑟, 1823-1905)가 번역하여 1886년에 간행한 〈西學啓蒙〉 16종 가운데 하나이다. 이상설의 〈植物學>은 이 〈植物學啓蒙〉을 읽으면서 그 책의 내용 중 당시의 조 선 학자가 모르고 있던 새로운 내용을 중심으로 메모를 한 것으로 여겨진다. 본 연구에서는 전통산학과 근대서양수학을 연결하는 〈數理〉를 저술했으며. 우리나라의 정규 교과과정에 수학과 과학을 필수과목으로 지정하고, 첫 번째 수학교과서 〈산術新書〉를 발간함으로 당대 최고의 수학자로 평가된 이상설이 쓴 〈植物學〉을 발굴하여 그 내용과 의미를 최초로 분석한다, 이를 통하여 당시 조선의 서양 과학, 특히 식물학에 대한 이해 수준을 분석하고 〈植物學〉의 원전인 〈植物學啓蒙〉 과 <西學啓蒙〉의 저자에 대하여 알아본다. 이는 당시 수학교육자가 자연과학분야에 행한 교육적 기여를 이해 하는데 필수적인 연구이다. This paper deals with contents that Sang-Seol Lee contributed to the natural science in the 19th century Korea. Prof. Sung-Rae Park, the science historian, called Sang-Seol Lee Father of the Modern Mathematics education of Korea. Sang-Seol Lee wrote a manuscript Botany with a brush in late 19th century. Botany was transcribed from Science Primers: Botany (written by J. D. Hooker), which is translated into Chinese by Joseph Edkins in 1886. The existence of Sang-Seol Lee`s book Botany was not known to Korean scientists before. In this paper, we study the contents of Botany and its original text. Also we analyze people`s level of understanding Western sciences, especially botany at that time. In addition, we study authors of 16 Primers for Western Knowledge. We study the contribution of mathematician Sang-Seol Lee to science education in the 19th century Korea.

Ultrasonic Degradation of Endocrine Disrupting Compounds in Seawater and Brackish Water

So Young Park,Jong Sung Park,Ha Yoon Lee,Ji Yong Heo,Yeo Min Yoon,Kyung Ho Choi,Nam Guk Her 대한환경공학회 2011 Environmental Engineering Research Vol.16 No.3

In this study, a series of experiments was conducted on the relative degradation of commonly known endocrine-disrupting compounds such as bisphenol A (BPA) and 17α-ethinyl estradiol (Ee₂) in a single-component aqueous solution using 28 and 580 kHz ultrasonic reactors. The experiments were conducted with three different types of model water: deionized water (DI), synthetic brackish water (SBW), and synthetic seawater (SSW) at pH 4, 7.5, and 11 in the presence of inert glass beads and humic acids. Significantly higher sonochemical degradation (93-97% for BPA) occurred at 580 kHz than at 28 kHz (43-61% for BPA), regardless of water type. A slightly higher degradation was observed for Ee₂ compared to that of BPA. The degradation rate of BPA and Ee₂ in DI water, SBW, and SSW after 30 min of ultrasound irradiation at 580 kHz increased slightly with the increase in pH from 4 (0.073-0.091 min-1 for BPA and 0.081-0.094 min-1 for Ee₂) to 7.5 (0.087-0.114 min-1 for BPA and 0.092?0.124 min-1 for Ee₂). In contrast, significant degradation was observed at pH 11 (0.149-0.221 min-1 for BPA and 0.147-0.228 min-1 for Ee₂). For the given frequencies of 28 and 580 kHz, the degradation rate increased in the presence of glass beads (0.1 mm and 25 g) for both BPA and Ee₂: 0.018-0.107 min-1 without beads and 0.052-0.142 min-1 with beads for BPA; 0.021-0.111 min-1 without beads and 0.054-0.136 min-1 with beads for Ee₂. A slight increase in degradation of both BPA and Ee₂ was found as the concentration of dissolved organic carbon (DOC, humic acids) increased in both SBW and SSW: 0.107-0.115 min-1 in SBW and 0.087-0.101 min-1 in SSW for BPA; 0.111-0.111 min-1 in SWB and 0.092-0.105 min-1 in SSW for Ee₂. After 30 min of sonicating the humic acid solution, DOC removal varied depending on the water type: 27% (3 mg L-1) and 7% (10 mg L-1) in SBW and 7% (3 mg L-1) and 4% (10 mg L-1) in SSW.

태연혈(太淵穴)의 유침 시간에 따른 체온 변화 -적외선체열촬영(赤外線體熱撮影)을 중심으로-

이봉효 ( Bong Hyo Lee ),이경민 ( Kyung Min Lee ),박지하 ( Ji Ha Park ),김민서 ( Min Seo Kim ),김산들 ( San Deul Kim ),박병규 ( Byeong Gyu Park ),양현동 ( Hyun Dong Yang ),예성호 ( Sung Ho Yea ),이호정 ( Ho Jung Lee ),최재원 ( Jae 경락경혈학회 2012 Korean Journal of Acupuncture Vol.29 No.2

Objectives: This study was performed to find the desirable remaining time of needle in the acupuncture treatment. Methods: The 21 volunteers were given acupuncture at LU9 vertically and needles were remained for 2 min, 10 min, 15 min, 30 min, respectively. The thermographic change induced by acupuncture was measured with Digital Infrared Thermographic Image at the following acupoints: LU11, LU10, LU9, LU8, LU5, LU1, and PC7. The statistical significance of thermographi change was evaluated using paired t-test and post hoc Wilcoxon test. Results: The most significant changes after acupuncture were produced when needles were remained for 10 min or 15 min. LU11, LU5, LU1, and PC7 were the point at which all of the remaining time produced significant change commonly. At LU11, the biggest change was produced when needle was remained for 15 min, while at LU5, LU1, and PC7, the biggest change was produced when needle was remained for 30 min, and the smallest change was produced when needle was remained for 10 min at all of acupoints of LU11, LU5, LU1, and PC7. The unbalance between left side and right was decreased the most largely in 15 min group. Conclusions: The results of this study suggest that the desirable remaining time of acupuncture needle might be 15 min.

인간포배기 배아의 효과적인 유리화 동결법의 개발을 위한 연구

이상민,이주희,이상원,이승민,윤산현,임진호,박흠대,이성구,Lee, Sang-Min,Lee, Ju-Hee,Lee, Sang-Won,Lee, Seoung-Min,Yoon, San-Hyun,Lim, Jin-Ho,Park, Huem-Dai,Lee, Seong-Goo 대한생식의학회 2003 Clinical and Experimental Reproductive Medicine Vol.30 No.3

Objective: The purpose of this study was to evaluate the survival rate of vitrified blastocyst according to the freezing vessels, equilibration time in cryoprotectant and artificial dehydration method. Methods: Human blastocysts were vitrified after loading onto the plastic straw, open-pulled straw (OPS), electron microscopy grid (EM grid) for 1.5 min or 3 min. They also were directly plunged into LN2 within 30sec. For artificial shrinkage of blastocysts, 36 gauge fine needle was pushed at the cellular junction of the trophectoderm into the blstocoele cavity until it shrank without damage of inner cell mass. Results: The survival rate of vitrified blastocysts on plastic straw, OPS, EM grid as freezing vessels were 26.7, 13.0 and 60.5%, respectively. The survival rate of EM grid was significantly higher than that of plastic straw and OPS (p<0.05). For 1.5 min equilibrium, the survival rates of early blastocyst (EB), middle blastocyst (MB) and late blastocyst (LB) were 64.4, 81.0, and 20.0% respectively. For 3 min equilibrium, the survival rates of EB, MB, and LB were 69.9, 50.0 and 57.5% respectively. The survival rates of EB and MB were significantly higher than that of LB in 1.5 min equilibrium group (p<0.05), however, the significance was not observed in 3 min equilibrium groups. In cytoplasmic shrinkage before vitrification, the survival rates of EB, MB and LB were 92.9, 100 and 75.9% respectively. The survival rate of MB was significantly higher than that of LB (p<0.05). The survival rates of vitrified blastocysts by artificial dehydration and slow-frozen blastocysts were not significantly different as 88.9 and 66.7%, respectively. Conclusion: This study showed that the vitrification of human blastocysts using EM grid and artificial dehydration is an effective method. Therefore, these methods would be an useful techniques for blastocyst cryopreservation.

Evaluation of High Power Light Emitting Diodes (HPLEDs) as Potential Attractants for Adult Spodoptera exigua (Hübner)

Min-Seok Oh,Sang-Guei Lee,Ju-Hyun Jeon,Hoi-Seon Lee 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.10

To response evaluation of high power light emitting diodes (HPLEDs) as potential attractants to the Spodoptera exigua adults, we investigated the attractiveness of specific wavelength, illuminance intensity and light-exposure time, and compared them to the fluorescent. The all light treatments with the 40 lux intensity attracted the significantly highest number of S. exigua. The optimal light-exposure time exhibited the highest attraction rate at the 60 min. When the attraction and repellent rate in the optimal conditions to the S. exigua was surveyed, the white HPLED exhibited the highest attraction rate (91.1%), whereas the red HPLED exhibited the most repellent rate (33.3%). When evatuated of illuminance efficiency with fluorescent as control, white and red HPLED were found to be 9.14 and 10.34 times more efficient than fluorescent. These data clearly show that both the 40 lux intensity and the 60 min light-exposure time by using the white HPLED was the most suitable for attraction of the S. exigua.

Conditioned Media of ASC-17D Sertoli Cells Induce G1-Growth Arrest of DU145 Human Prostate Cancer Cells

Min, Bon Hong,Kang, Sang Wook,Lee, Kwang Ho,Choi, Sang Hyun,Kang, Hyeog,Chun, Boe Gwun The Korea Science and Technology Center 1998 BMB Reports Vol.31 No.5

We studied the effects of ASC-17D rat Sertoli cell-conditioned media (rSCCM) on the proliferation of the DU145 prostate cancer cells. rSCCM was prepared from ASC-17D cells cultured in DMEM/F-12 serum-free media at a nonpermissive temperature of 40℃, which is the condition for the high expression of clusterin. We found that rSCCM could inhibit the proliferation of DU145 cells by arresting the cell cycle in the G1 phase in a dose-dependent manner. This growth arresting activity was abolished by boiling rSCCM for 5 min. The G1 growth-inhibiting activity of rSCCM was also detected in other prostate-originated cancer cells examined (ie., LNCaP and PC-3) but not in other cells (ASC-17D, HepG2, SK-N-SH, and NIH3T3). Western blot analysis of partially purified growth inhibiting fractions with the clusterin antibody showed that the cytostatic factor in rSCCM was not clusterin. This cytostatic factor was semipurified by DEAE-Sepharose, ammonium sulfate precipitation, and Phenyl-Sepharose column chromatography, and was estimated to have a molecular weight of 88 kDa by Sephacryl S-300 gel filtration.

Evaluation of High Power Light Emitting Diodes (HPLEDs) as Potential Attractants for Adult Spodoptera exigua (Hubner) (Lepidoptera Noctuidae)

( Min Seok Oh ),( Chi Hoon Lee ),( Sang Guei Lee ),( Hoi Seon Lee ) 한국응용생명화학회 2011 Applied Biological Chemistry (Appl Biol Chem) Vol.54 No.3

To evaluate high-power light-emitting diodes (HPLEDs) as potential attractants for Spodoptera exigua adults, attractiveness of specific wavelengths, illuminance intensity, and light-exposure times were investigated and compared to that of fluorescent light. The white light (40 lux treatment) attracted significantly more S. exigua than other attractants. The optimal light-exposure time, based on the highest attraction rate, was 60 min. Evaluation of attraction and repellent rates under optimal conditions showed the white HPLED had the highest attraction rate (91.1%), and the red HPLED had the highest repellence rate (33.3%). Based on relative efficiency values, the white HPLED was about 9.14 times as efficient as the fluorescent light. These data clearly showed that S. exigua showed the greatest attraction to the white HPLED at 40 lux intensity and 60 min light-exposure time.

Effect of Forging Type on the Deformation Heterogeneities in Multi‑Axial Diagonal Forged AA1100

Min‑Seong Kim,Sang‑Chul Kwon,Sun‑Tae Kim,Seong Lee,Hyo‑Tae Jeong,Shi‑Hoon Choi 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.3

The present study investigated the effects that different types of forging exert on the deformation heterogeneities developedin AA1100 during multi-axial diagonal forging. To measure the deformation heterogeneities of deformed workpieces, thevalues for hardness and Kernel average misorientation were measured at the center section following each forging process. Type-D forging that consists of diagonal forging and return-diagonal forging was relatively advantageous compared withType-P forging that includes plane forging and return-plane forging for minimizing the non-uniformity of deformationdeveloped in workpieces. The effective strain developed in a workpiece during the 2 types of forging was simulated using3-D FEA. FEA revealed that the positions and degrees of occurrence for soft and hard-zones in workpieces vary greatlydepending on the forging type. Type-D forging was relatively advantageous compared with Type-P forging for minimizingthe non-uniformity of effective strain developed in workpieces.