Optimizing Ganoderma lucidum Mycelial Production Using Swine Wastewater as a Substrate

Jangwoo LEE,Jinmo AHN,Gyuseong HAN,Joonyeob LEE,Taewoan KOO,Seokhwan HWANG 한국생물공학회 2014 한국생물공학회 학술대회 Vol.2014 No.10

Quantitative and qualitative changes in antibiotic resistance genes after passing through treatment processes in municipal wastewater treatment plants

Lee, Jangwoo,Jeon, Jong Hun,Shin, Jingyeong,Jang, Hyun Min,Kim, Sungpyo,Song, Myoung Seok,Kim, Young Mo Elsevier 2017 The Science of the total environment Vol.605 No.-

<P><B>Abstract</B></P> <P>In this study, quantitative and qualitative changes in antibiotics resistance genes (ARGs) were investigated in two municipal wastewater treatment plants (WWTPs) treating pretreated livestock or industrial wastewater as well as municipal sewage. Total eight ARGs (<I>tet</I>X, <I>tet</I>M, <I>tet</I>A, <I>sul</I>1, <I>sul</I>2, <I>erm</I>B, <I>qnr</I>D, and <I>bla</I> <SUB>TEM</SUB>) were quantified, and their relative abundance was assessed by ARGs copies/16S rRNA gene copies. The fate of ARGs was observed to be different between two WWTPs: <I>sul</I>, <I>qnr</I>D, and <I>bla</I> <SUB>TEM</SUB> were proliferated during the treatment processes only in the WWTP1 which received pretreated livestock wastewater. Furthermore, dynamic shifts in patterns of ARGs occurrence were observed during biological, secondary sedimentation and coagulation processes. During biological treatment in both WWTPs, relative abundance of <I>tet</I> and <I>erm</I>B changed: <I>tet</I> increased significantly by 211.6–357.6%, while <I>erm</I>B decreased by 70.4–92.0%. Little variation was observed in <I>sul</I>, <I>qnr</I>D and <I>bla</I> <SUB>TEM</SUB>. Subsequently, the relative abundance of <I>tet</I> decreased during the secondary sedimentation and coagulation in both WWTPs: <I>tet</I> decreased by 56.0–86.3% during sedimentation and by 48.2–75.7% during coagulation, respectively. During the final treatment, different responses of antibiotic resistance bacteria (ARB) and ARGs to ultraviolet (UV) disinfection were found: removal efficiencies of ARB were observed in the range of 34–75%, while obvious reduction in ARGs was not observed at the UV dose of 27mJ/cm<SUP>2</SUP>. Although ARGs underwent various treatment processes, considerable levels of ARGs remained at discharge amounting to 4.2×10<SUP>18</SUP> copies/day from WWTP1 and 5.4×10<SUP>16</SUP> copies/day from WWTP2, respectively.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Quantitative and qualitative changes in ARGs were investigated in WWTPs. </LI> <LI> Changes were unique for each ARG community while undergoing treatment processes. </LI> <LI> Variation in ARGs was largest during biological and post-physiochemical processes. </LI> <LI> ARGs showed limited response to UV disinfection. </LI> <LI> ARB were reduced by UV disinfection. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

The Strategy-Environment Match and Performance in Two Technological Settings : An Empirical Study in the Korean Textile Industry 韓國의 纖維産業 實證硏究

Lee, Jangwoo 慶北大學校 經濟經營硏究所 1993 經商論集 Vol.21 No.2

Inter-pin skew compensation method for 3.2Gbps/pin DDR4 SDRAM interface

Jangwoo Lee,Younghoon Kim,Changsik Yoo 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

For inter-pin skew reduction with fast operation time and minimum hardware increase in DDR4 SDRAM interface, an inter-pin skew compensation algorithm using SAR (Successive Approximation Register) is proposed. The proposed algorithm implemented in a 0.18㎛ CMOS process shows that all pins can be aligned in 324 cycles when preamble sequence operates at 400㎒.

Bisphenol A distribution in serum, urine, placenta, breast milk, and umbilical cord serum in a birth panel of mother–neonate pairs

Lee, Jangwoo,Choi, Kyungho,Park, Jeongim,Moon, Hyo-Bang,Choi, Gyuyeon,Lee, Jeong Jae,Suh, Eunsook,Kim, Hai-Joong,Eun, So-Hee,Kim, Gun-Ha,Cho, Geum Joon,Kim, Sung Koo,Kim, Sungjoo,Kim, Su Young,Kim, Se Elsevier 2018 Science of the Total Environment Vol.626 No.-

<P><B>Abstract</B></P> <P>Bisphenol A (BPA) exposure during the perinatal and postnatal periods increases the susceptibility to disease over the life cycle. However, information on the BPA delivered to fetuses or infants via the placenta and breastfeeding is limited. We determined the BPA exposure levels in various bodily fluids and tissues of pregnant women and described fetus and infant exposures to BPA based on associations and BPA ratios in mother–neonate paired samples. Maternal serum, urine, placenta, breast milk, cord serum, and neonatal urine samples were collected from 318 mother–neonate pairs at six university hospitals in Korea. BPA levels were detected using liquid chromatography tandem mass spectrometry. The ratios of the BPA levels in the other sample types to the levels in maternal serum were calculated. BPA was detected in 79.5–100% of the maternal and fetal samples. The median BPA concentration in the samples decreased in the order of neonatal urine (4.75ng/mL), maternal urine (2.86ng/mL), cord serum (1.71ng/mL), maternal serum (1.56ng/mL), breast milk (0.74ng/mL), and the placenta (0.53ng/g). We estimated the ratios of BPA levels in the other sample types to those in maternal serum. The median (95th percentile) cord serum-to-maternal serum ratio was 1.12 (15.2) for 160 mother–fetal pairs, in which BPA was detected in both samples. The placenta-, maternal urine-, neonatal urine-, and breast milk-to-maternal serum ratios were 0.28 (5.31), 1.79 (29.9), 1.98 (28.2), and 0.51 (10.5), respectively. In addition, the median (95th percentile) cord serum-to-placenta ratio was 4.03 (45.8), and the neonatal urine-to-cord serum ratio was 1.95 (25.6). The 95th percentile values were 14–20-fold greater than the medians. Urine contained the highest BPA concentrations, followed by serum, breast milk, and the placenta. The variations of BPA ratio show individual differences in the amounts of BPA delivered from mother to fetus.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Not enough data on tissue distribution of BPA in mother‑neonate (or fetus) pair </LI> <LI> The order of BPA concentrations in examined tissue or bio-samples are urine in mother and neonates>cord serum>maternal serum>breast milk>placenta. </LI> <LI> BPA in cord serum, significantly associated with in maternal serum and urine but not in others. </LI> <LI> The variations of BPA ratio show individual differences in the amounts of BPA delivered from mother to fetus. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

DEHP, DEP and DBP Exposure Analysis using Urinary Metabolites of Gyonggi Province University Students

Lee, JangWoo,Kho, YoungLim,Kim, SungKyoon,Choi, Kyungho,Hwang, SeongHee,Jeong, Jeeyeon,Kim, Pangyi Korean Society of Environmental Health 2013 한국환경보건학회지 Vol.39 No.5

Objectives: Phthalates are used as plasticizers in polyvinyl chloride (PVC) plastics. As phthalate plasticizers are not chemically bound to the PVC, they can leach, migrate or evaporate into indoor air and atmosphere, foodstuffs, other materials, etc. Therefore, humans are exposed through ingestion, inhalation, and dermal exposure over their entire lifetime, including during intrauterine development. In particular, university students have a great number of opportunities to contact products including phthalates during campus life (food packaging, body care products, cosmetic, lotions, aftershave, perfume etc.). The purpose of this study was to examine levels of phthalate exposure as undergraduate students begin to use pharmaceuticals and personal care products including phthalates. Methods: Phthalate metabolites, mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), mono-2- ethylhexyl phthalate (MEHP), {(mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP}, and mono-(2-ethlyl-5-oxohexyl) phthalate (MEOHP} were examined. 80 urine samples collected from university students were analyzed using LC/MS/MS(API 4000, Applied Bioscience) with on-line enrichment and columnswitching techniques. This study was carried out at Y university located in Gyonggi Province from 2008 to 2011. Results: The detection limit of phthalate metabolites were 0.03 ng/mL for MEP, 0.11 ng/mL for MnBP, 0.08 ng/mL for MiBP, 0.93 ng/mL for MEHP, 0.19 ng/mL for MEOHP and 0.16ng/mL for MEHHP. MnBP showed the highest urinary levels (median: 31.6 ug/L, 24.8 ug/g creatinine (cr)). Concentrations were also high for MEHHP (median: 24.1 ug/L, 19.0 ug/g cr), followed by MEOHP (median: 22.8 ug/L, 17.9 ug/g cr). In individual cases, the maximum level reached up to 348 ug/L, and 291 ug/g cr, respectively. The urinary and creatinine adjusted levels of MEP were lower than those for DBP and DEHP metabolites, but were higher in 95th percentiles. As a result, the mean daily DEP intake value was 2.3 ${\mu}g/kg$ bw/day, 3.5 ${\mu}g/kg$ bw/day for DEHP and 4.9 ${\mu}g/kg$ bw/day for DBP. Conclusion: These students' phthalate exposure levels were below the international safe level set by the EU, but higher than the 2012 KFDA survey of the age group from 3 to 18.

An 8-b 1GS/s Fractional Folding CMOS Analog-to-Digital Converter with an Arithmetic Digital Encoding Technique

Lee, Seongjoo,Lee, Jangwoo,Lee, Mun-Kyo,Nah, Sun-Phil,Song, Minkyu The Institute of Electronics and Information Engin 2013 Journal of semiconductor technology and science Vol.13 No.5

A fractional folding analog-to-digital converter (ADC) with a novel arithmetic digital encoding technique is discussed. In order to reduce the asymmetry errors of the boundary conditions for the conventional folding ADC, a structure using an odd number of folding blocks and fractional folding rate is proposed. To implement the fractional technique, a new arithmetic digital encoding technique composed of a memory and an adder is described. Further, the coding errors generated by device mismatching and other external factors are minimized, since an iterating offset self-calibration technique is adopted with a digital error correction logic. A prototype 8-bit 1GS/s ADC has been fabricated using an 1.2V 0.13 um 1-poly 6-metal CMOS process. The effective chip area is $2.1mm^2$(ADC core : $1.4mm^2$, calibration engine : $0.7mm^2$), and the power consumption is 88 mW. The measured SNDR is 46.22 dB at the conversion rate of 1 GS/s. Both values of INL and DNL are within 1 LSB.

DEHP, DEP and DBP Exposure Analysis using Urinary Metabolites of Gyonggi Province University Students

JangWoo Lee,YoungLim Kho,SungKyoon Kim,Kyungho Choi,SeongHee Hwang,Jeeyeon Jeong,Pangyi Ki 한국환경보건학회 2013 한국환경보건학회지 Vol.39 No.5

Objectives: Phthalates are used as plasticizers in polyvinyl chloride (PVC) plastics. As phthalate plasticizers are not chemically bound to the PVC, they can leach, migrate or evaporate into indoor air and atmosphere, foodstuffs, other materials, etc. Therefore, humans are exposed through ingestion, inhalation, and dermal exposure over their entire lifetime, including during intrauterine development. In particular, university students have a great number of opportunities to contact products including phthalates during campus life (food packaging, body care products, cosmetic, lotions, aftershave, perfume etc.). The purpose of this study was to examine levels of phthalate exposure as undergraduate students begin to use pharmaceuticals and personal care products including phthalates. Methods: Phthalate metabolites, mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), mono-2- ethylhexyl phthalate (MEHP), {(mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP}, and mono-(2-ethlyl-5-oxohexyl) phthalate (MEOHP} were examined. 80 urine samples collected from university students were analyzed using LC/MS/MS(API 4000, Applied Bioscience) with on-line enrichment and columnswitching techniques. This study was carried out at Y university located in Gyonggi Province from 2008 to 2011. Results: The detection limit of phthalate metabolites were 0.03 ng/mL for MEP, 0.11 ng/mL for MnBP, 0.08 ng/mL for MiBP, 0.93 ng/mL for MEHP, 0.19 ng/mL for MEOHP and 0.16ng/mL for MEHHP. MnBP showed the highest urinary levels (median: 31.6 ug/L, 24.8 ug/g creatinine (cr)). Concentrations were also high for MEHHP (median: 24.1 ug/L, 19.0 ug/g cr), followed by MEOHP (median: 22.8 ug/L, 17.9 ug/g cr). In individual cases, the maximum level reached up to 348 ug/L, and 291 ug/g cr, respectively. The urinary and creatinine adjusted levels of MEP were lower than those for DBP and DEHP metabolites, but were higher in 95th percentiles. As a result, the mean daily DEP intake value was 2.3 μg/kg bw/day, 3.5 μg/kg bw/day for DEHP and 4.9 μg/kg bw/ day for DBP. Conclusion: These students’ phthalate exposure levels were below the international safe level set by the EU, but higher than the 2012 KFDA survey of the age group from 3 to 18.

Technology Acquisition Strategies in the Korean Computer Industry : A Micro Perspective

Lee, Jangwoo 경북대학교 경제경영연구소 1989 經商論集 Vol.17 No.2

With the computer industry as the case in point, this paper examines how local firms in Korea acquired technological capabilities which enabled them to enter new technology industries and sustain phenomenal growth in the international market. Investigating technological behaviors of 44 local firms in the Koran computer industry, it identifies different patterns of technological strategy associated with four types of firms, which is categorized by two variables : the production capablility and innovation capability at the time of entry into the industry. Statistical analyses suggest that technology acquisition strategies are distinctly different among four types of firms.

Characterization of antibiotic resistance genes in representative organic solid wastes: Food waste-recycling wastewater, manure, and sewage sludge

Lee, Jangwoo,Shin, Seung Gu,Jang, Hyun Min,Kim, Young Beom,Lee, Joonyeob,Kim, Young Mo Elsevier 2017 Science of the Total Environment Vol.579 No.-

<P><B>Abstract</B></P> <P>In this research, the distribution of antibiotic resistance genes (ARGs) was characterized in representative organic solid waste (OSW) in Korea: food waste-recycling wastewater (FRW), manure, and sewage sludge. The amounts of total ARG (gene copies/16S rRNA gene copies) was greatest in manure followed by sewage sludge and FRW. Interestingly, there were significantly different patterns in the diversity and mechanisms of ARGs. For example, a significant proportion of ARGs were tetracycline resistant genes in all the OSW (40.4–78.2%). β-lactam antibiotics resistant genes were higher in the FRW samples than in other types of OSW but sulfonamides resistant genes represented the greatest proportion in sludge. Regarding the characteristics of antibiotic resistance mechanisms, there was a relatively higher proportion of the ribosomal protection mechanism to tetracycline observed in the FRW and manure samples. However, tetracycline resistant genes with direct interaction were relatively higher in the sewage sludge samples. <I>sul</I>1 was the dominant subtype in all the OSW types and detection of <I>erm</I>B was observed although there was no <I>erm</I>C detected in sewage sludge. There were significant correlations between the occurrences of ARG subtypes: <I>tet</I>B and <I>tet</I>G in all OSW (<I>P</I> <0.01); <I>tet</I>E and <I>tet</I>Q only in sludge (<I>P</I> <0.01). The Class 1 integron-integrase gene (<I>intI</I>1) was significantly correlated with total ARGs only in manure and sludge (<I>P</I> <0.05), revealing potential horizontal gene transfer in these OSW.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Total relative amount of ARGs were highest in the manure, followed by sludge, and FRW. </LI> <LI> Diversity and mechanisms of ARGs were significantly different between OSWs. </LI> <LI> Sulfonamides resistant genes represented the greatest proportion in sludge. </LI> <LI> The ribosomal protection mechanism to tetracycline was dominant in FRW and manure. </LI> <LI> Total ARGs and <I>intI</I>1 were positively correlated in manure and sludge, but not in FRW. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>