폐경기 여성에서 호르몬 대치 요법시 병행 투여된 프로제스토젠 투여 방법에 따른 혈청 지질 및 지단백에 미치는 영향

이임순,전섭,이순곤,이해혁,이권해,정집광,이석민 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.1

Objective : The purpose of our study is to evaluate the effect of different administration method of progestogen on lipid profiles including total cholesterol, LDL(low density lipoprotein)-cholesterol, HDL(high density lipoprotein)-cholesterol, triglycerides during hormone replacement therapy in postmenopausal women. Methods and Materials : Seventy-one postmenopausal women who were assigned to following groups (Group I : conjugated equine estrogen(CEE), 0.625 mg/day plus continuous medroxyprogesterone acetate (MPA), 2.5mg/day, Group II : CEE, 0.625 mg/day plus cyclic MPA, 5mg/day for 12days/month. And we measured serum total cholesterol, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol, and triglycerides before hormone replacement therapy(HRT) and 12 months later after hormone replacement therapy. Results: 1. Total cholesterol decreased in group I,III. 2. HDL-cholesterol increased in group I,II,III. 3. LDL-cholesterol decrease in group I,II. 4. Triglycerides increased in group I,II,III. There was significance in serum total cholesterol and LDL-cholestrerol among three groups. Conclusions : Estrogen alone or in combination with progestogen both in cyclic and continuous use improves lipid profiles, so medroxyprogesterone acetate(MPA) does not seem to blunt estrogenic effect on lipid profiles.

SD Rats를 이용 1-hexene의 흡입독성 연구

김현영,임철홍,정용현,이권섭,이성배,이준연,한정희,전윤석,이용묵 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4

The purpose of this study was to investigate the acute (4 hours) and repeated-dose (6 hours a day, 5 days a week, 4 weeks) toxic effects of I -hexene on Sprague- Dawley (SD) rats which were treated by inhalation. The results were as follows; I. The median lethal concentration (LC_(50)) was estimated 52,694 ppm (confidence limit 95%; 49,494~55,447 ppm) in acute inhalation. Abnormal clinical signs related to the l-Hexene were not observed with the acute inhalation dose. Gross findings of necropsy revealed on evidence of specific toxicity related to the 1-hexene, II. By repeated inhalation exposure the body weight of male were more or less reduced by the dose of 2,500 ppm and 5,000 ppm compared with control group. However there were no significant variation hematology and blood biochemistry for the exposed rats compared with the control rats. Abnormal clinical signs and gross findings of necropsy related to the 1-hexene were not shown. In conclusion when we exposed I-hexene to SD rats for 4 weeks, 5 days per week, 6 hours per day, the Lowest observed effect level (LOEL) was over 2,500 ppm and Non observed effect level (NOEL) was below 500 ppm.

크롬(Ⅵ)의 체내 흡수와 소실속도에 관한 연구

김현영,이성배,임철홍,이권섭,정용현,이종성,한정희,전윤석,황호순,이용묵 한국산업위생학회 2003 한국산업보건학회지 Vol.13 No.1

The CrO3 mostly used in plating. metal surface disposal, leather, cosmetic manufacturing, as an experiment material by repeatedly inhaling and exposure the male S.D. rats at a 0.00, 0.2., 0.50, 1.25 mg/㎡ concentration(particle size: 0.5-0.5 aerosol)6hours a day, 5day a week in 13weeks comparing with 2weeks, 8weeks of recovery group about the noxiousness of the experiment animal and the reduce scale of the CrO3 in the internal organ especially in blook and respiratory organ with the period of convalescent and clearance. The experiment results which we received are as follows. 1. In blood the RBC, HGB and HCT experiment, rats with 0.20, 0.50 mg/㎡ concentration showed that there were some decreases but not dependent. The kidneys absolute weight compared with control group was reduced intentionally(p〈0.05) and the lungs absolute weight compared with control group showed intentional increase(p〉0.05). 2. After the exposure of the experiment material, the whole blook, l\blood plasma and red blood cell in blood by (x): the period of convalescent, per (y); the decreasing of Cr concentration, was y=66.51 e -0.057x, y=67.2 e-0.101x, y=70.01 e-0.030 in 0.50 mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life (day)was estimated 12.0, 6086, 23.0 each. 3, After the exposure of the experiment material, the experiment animals lung, liver and kidneys by(x); the period of convalescent, per (y); the decreasing of Cr conentration, was y=1808 e-0.00493x, y=12.02e-0.0297x, y=67.61 e-0.0292x in 0.50mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life(day)was estimated 140.6, 23.3, 23.7, each, and including lung, liver with all of the experiment internal organs, the Cr clearance decreased as the exposure concentration increased.

Histone occupancy-dependent and -independent removal of H3K27 trimethylation at cold-responsive genes in Arabidopsis

Kwon, Chang Seob,Lee, Daeyoup,Choi, Giltsu,Chung, Won-Il Blackwell Publishing Ltd 2009 The Plant journal Vol.60 No.1

<P>Summary</P><P>Trimethylation of histone H3 at lysine 27 (H3K27me3) is a histone marker that is present in inactive gene loci in both plants and animals. Transcription of some of the genes with H3K27me3 should be induced by internal or external cues, yet the dynamic fate of H3K27me3 in these genes during transcriptional regulation is poorly understood in plants. Here we show that H3K27me3 in two cold-responsive genes, <I>COR15A</I> and <I>ATGOLS3</I>, decreases gradually in Arabidopsis during exposure to cold temperatures. We found that removal of H3K27me3 can occur by both histone occupancy-dependent and -independent mechanisms. Upon cold exposure, histone H3 levels decreased in the promoter regions of <I>COR15A</I> and <I>ATGOLS3</I> but not in their transcribed regions. When we returned cold-exposed plants to normal growth conditions, transcription of <I>COR15A</I> and <I>ATGOLS3</I> was completely repressed to the initial level before cold exposure in 1 day. In contrast, plants still maintained the cold-triggered decrease in H3K27me3 at <I>COR15A</I> and <I>ATGOLS3</I>, but this decrease did not enhance transcriptional induction of the two genes upon re-exposure to cold. Taken together, these results indicate that gene activation is not inhibited by H3K27me3 itself but rather leads to removal of H3K27me3, and that H3K27me3 can be inherited at a quantitative level, thereby serving as a memory marker for recent transcriptional activity in Arabidopsis.</P>

Effects of Environmental Factors on the Characteristics of Microbial Communities in the Estuary of Naktong River

Kwon, O Seob 인제대학교 1988 仁濟論叢 Vol.4 No.2

낙동강 하구에 분포하는 대부분의 무기영양염류와 세균은 육상 및 담수생태계에서 유입된 것으로 나타났으며, 또한 미생물 개체수의 변화는 정점별로 변하는 환경인자에 의해 큰 영향을 받는 것으로 나타났다. 환경인자에 의한 요인분석 결과에 의하면 담수 및 분변성 오염원의 유입, 하계의 강우에 의한 육상토양성분의 유입, 해수의 영향, 일조량 등의 4가지 현상이 낙동강 하구 생태계의 주요인으로 작용하여 전체 변화의 65.3%를 설명할 수 있었다. Most bacterial groups and inorganic nutrients of Naktong Estuary were thought to be originated from freshwater or terrestrial ecosystems. Effects of environmental factors such as pH, salinity, and nutrients which varied between stations were more significant than those of temporally varied factors such as temperature, dissolved oxygen, precipitation, and radiation on the distribution of bacteria except spore-forming bacteria. Factor analysis with 21 environmental parameters led to extraction of 4 factors that accounted for 65.3% of the ecosystem variation of Naktong Estuary. The factors were identified in the following orders: 1) effect of freshwater and fecal contamination, 2) effect of soil content by precipitation in summer, 3) effect of seawater, 4) effect of summertime.

Hierarchical Interconnection Network based on the ATM Switch for Multicomputer Systems

Kwon, Bo-seob 安東大學校 工業技術硏究所 1999 공업기술연구논문집 Vol.6 No.1

메시지 기반 멀티컴퓨터시스템에서는 빠른 프로세서간 통신이 필요하다. 다양한 프로세서간 통신방법중에서 본 논문은 비동기 전송모드(ATM) 스위치를 사용하여 낮은 지연시간과 높은 처리율을 얻을 수 있는 방법을 제안한다. 이 구조는 프로세서간 통신을 셀 크기로 전송하고, 셀들의 멀티플렉싱과 디멀티플렉싱을 담당하는 셀 인터페이스 모듈을 둔 계층적 구조를 가지고 있다. 라우팅 전략은 스위칭 라우팅 정보, VPI, VCI로 사용한다. In a message-based multiprocessor system that consists of message-communicating processors, the interconnection network is really a crucial part for fast processor communication. Among various interconnection methods, using the high-speed asynchronous transfer mode(ATM) switch is an attractive approach to constructing large-scale multiprocessor systems with low latency and high throughput. The interconnection network for fast processor communication is proposed in this paper. For the efficient use of the ATM switch, a group of the cell interface module(CIM) called a cell router which performs cell multiplexing and demultiplexing, is located between the processors groups and the ATM switch. In this proposed system, an expanded internal cell format in which three bytes are added for the switch routing information, is used. The interconnection network uses three routing strategies: the ATM switch routing using the switch routing information, the cell router routing using the virtual path identifier(VPI), and the cell reassembly routing using the virtual channel identifier(VCI). The interconnection network consists of an N×N folded switch and N cell routers.

The Influence of Discussion-based Teaching Method of Online Education on the Effectiveness of Adult Learning

( Kwon-seob So ),( Hye-jeong Hwang ) 융합연구학회 2021 융합연구학회지 Vol.5 No.2

This study was conducted to understand the effect of discussion-type online education on the learning effect of 696 people who took the discussion-type learning at K Cyber University. The collected data were analyzed using ANOVA. As a result of the study, the learning effect increased in all items in 2020 compared to 2019. In the analysis by grade level, there was no significant difference in 2019, but in 2020, the Freshman significantly decreased in learning motivation, interaction and cognitive participation, satisfaction, perceived usefulness, and learning achievement. In the analysis by age, in 2019, learning motivation, cognitive participation, perceived usefulness, interaction, and immersion were significantly higher in the age group over 60 years old. In 2020, the motivation for learning was higher in the age group over 60 years old, and in interaction and cognitive participation, under 39 years old and over 60 years old were higher, academic achievement was under 39 years old, and loyalty was under 39 years old and 50-59 years old were higher. As a result, discussion-based learning can be said to be a learning method to improve the learner’s class satisfaction. As a measure to improve learner satisfaction in the future, it is necessary to prepare a basic approach to improve the learning effect for first graders, who have poor learning effects in all items, and to develop various customized learning programs to improve the learning effect by age group.

Improvement of Transient Step Response Using Feedforward Compensator in Nonminimum Phase Systems

Kwon, Byung-Moon,Ryu, Hee-Seob,Kwon, Oh-Kyu Institute of Control 2001 Transaction on control, automation and systems eng Vol.3 No.3

This paper proposes a simple feedforward compensator in order to decrease the amount of undershoots and overshoots on the step response in nonminimum phase systems. The compensator makes the step type input be a ramp input with saturation for 0$\leq$t<${\alpha}$. It is shown in this paper that the compensated system has small amount of undershoot and overshoot at the price of rise time compared to the system without compensator. Also, provided the system is properly stable, the influence of the design parameter ${\alpha}$ on the step response of the nonminimum phase system is investigated in the case of Type A, and Type B undershoot, which gives a guideline for the compensator design.

Influence of Transition-Metal Cofactors on the Reductive Dechlorination of Polychlorinated Biphenyls (PCBs)

Kwon, O-Seob,Kim, Young-Jin,Cho, Kyung-Je,Lee, Jin-Ae,Kim, Young-Eui,Hwang, In-Young,Kwon, Jae-Hyun The Microbiological Society of Korea 2003 The journal of microbiology Vol.41 No.3

To enhance the reductive dechlorination of polychlorinated biphenyls (PCBs) under anaerobic conditions, we examined the adjunctive effects of cobalt (Co) and nickel (Ni), which are the central metals of transition-metal cofactors of coenzyme F$\_$430/ and vitamin B$\_$12/, respectively, on the dechlorination of Aroclor 1248. After 32 weeks of incubation, the average numbers of chlorines per biphenyl in culture vials supplemented with 0.2, 0.5, and 1.0 mM of Co reduced from 3.88 to 3.39, 2.92, and 3.28, respectively. However, the numbers of chlorine after supplementing with Ni decreased from 3.88 to 3.43, regardless of the Ni concentrations. The observed congener distribution patterns of all vials with different conditions were similar to the pattern produced by the dechlorination process of H' after 21 weeks of incubation, and these patterns were unchanged up to week 32, except for vials supplemented with 0.5 and 1.0 mM of Co. In vials containing 0.5 mM of Co, meta-rich congeners, such as 25/ 25-,24/25-, and 25/23-chlorobiphenyls (CBPs), which were found as accumulated products of dechlorination in other conditions, were further dechlorinated, and 25/2-, 24/2-, and 2/2-CBPs were concomitantly increased after 32 weeks of incubation. In this case, the congener distribution was similar to the dechlorination pattern of process M. From these results, we suggested that the enrichment of cultures with Co might stimulate the growth of specific populations of meta-dechlorinators, and that populations might promote a change in the dechlorination process from H' to M, which is known to be less effective on the dechlorination of the more highly chlorinated congeners of PCBs.

A One-Kilobit PQR-CMOS Smart Pixel Array

Kwon-Seob Lim,권오대,Jung-Yeon Kim,Sang-Kyeom Kim,Byeong-Hoon Park 한국전자통신연구원 2004 ETRI Journal Vol.26 No.1

The photonic quantum ring (PQR) laser is a three dimensional whispering gallery (WG) mode laser and has anomalous quantum wire properties, such as microampere to nanoampere range threshold currents and dependent - T thermal red shifts. We observed uniform bottom emissions from a 1-kb smart pixel chip of a 32×32 InGaAs PQR laser array flip-chip bonded to a 0.35 µm CMOS-based PQR laser driver. The PQR-CMOS smart pixel array, now operating at 30 MHz, will be improved to the GHz frequency range through device and circuit optimization. to nanoampere range threshold currents and T-dependent thermal red shifts. We observed uniform bottom emissions from a 1-kb smart pixel chip of a 32×32 InGaAs PQR laser array flip-chip bonded to a 0.35 μm CMOS-based PQR laser driver. The PQR-CMOS smart pixel array, now operating at 30 MHz, will be improved to the GHz frequency range through device and circuit optimization.