• 제목/요약/키워드: endogenous factors

검색결과 277건 처리시간 0.026초

불확실성을 갖는 작업 할당 문제를 위한 표본 평균 근사법 (Sample Average Approximation Method for Task Assignment with Uncertainty)

  • 김광
    • 한국산업정보학회논문지
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    • 제28권1호
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    • pp.27-34
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    • 2023
  • 최상의 에이전트-작업 할당을 결정하는 문제는 조합 최적화(combinatorial optimization)의 대표적인 문제이자 NP-난해(NP-hard)임이 알려져 있다. 본 연구에서는 에이전트와 작업의 할당 시 결정되는 작업 수행 확률(completion probability)이 불확실한 상황에서의 문제를 다룬다. 에이전트나 작업 내부의 요인 혹은 시스템 외적인 요소로 인한 작업 수행 확률은 고정적이기보다 불확실성을 갖는 것이 일반적이다. 불확실성을 고려하지 않은 할당 결정은 변동성이 있는 현실 상황에서 효과적이지 않은 결정이 될 수 있다. 작업 수행 확률의 불확실성을 수학적으로 반영하기 위해 본 연 구에서는 추계적 계획법(stochastic programming)을 활용한 수리 모형을 제시한다. 본 연구에서는 효율적으로 문제를 풀기 위해 표본 평균 근사법(sample average approximation)을 활용한 알고리즘을 제안한다. 본 문제 해결 방법론을 이용해 효과적인 할당 결정과 상한값과 하한값을 구할 수 있고, 결과의 성능을 확인하기 위해 최적 격차(optimality gap)와 분산을 실험을 통해 제시한다. 이를 통해 알고리즘으로 구한 할당 결정의 우수성 및 강건성을 보인다.

미국 인터넷 내용규제의 정치: 신제도주의로 본 연방통신품위법 230조 개정 논의 (The Politics of Internet Content Regulation in the U.S.: A Case Study on Communications Decency Act Section 230 Reform with New Institutionalist Approach)

  • 최재동
    • 정보화정책
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    • 제29권3호
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    • pp.48-60
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    • 2022
  • 이 연구는 미국 연방통신품위법 230조의 개정 논의를 신제도주의의 관점에서 분석하였다. 지금까지 내구력을 유지하며 미국 인터넷 내용규제의 기본틀을 구성해왔던 연방통신품위법 230조의 면책 조항은 오늘날 중대한 전환에 직면해 있다. 이 조항을 개폐하려는 정치적 시도들이 초당적인 협력으로 진행되고 있기 때문이다. 역사적 제도주의의 관점으로 연방통신품위법 230조의 개폐 논의를 분석한 결과, 미국 인터넷 내용규제 레짐의 변동은 가짜뉴스나 개인 정보 유출과 같은 외생적 사건과 함께, 행위자 간의 경쟁과 갈등이라는 내생적 요인이 복합적으로 작용해 발생한 것으로 여겨진다. 이상의 분석은 한국의 인터넷 내용규제 거버넌스의 제도개선과 방향성에 대해서도 함의를 지닐 수 있다.

주의력결핍 과잉행동장애 치료제 개발을 위한 카테콜아민계 표적화 (Targeting Catecholamines to Develop New Drugs for Attention Deficit Hyperactivity Disorder)

  • 정성철;조창환;김혜지;고은아;하민우;권오빈
    • Journal of Medicine and Life Science
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    • 제18권3호
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    • pp.41-48
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    • 2021
  • The prevalence of attention deficit hyperactivity disorder (ADHD), a developmental neuropsychiatric disorder, is high among children and adolescents. The pathogenesis of ADHD is mediated with genetic, biological, and environmental factors. Most therapeutic drugs for ADHD have so far targeted biological causes, primarily by regulating catecholaminergic neurotransmitters. However, ADHD drugs that are clinically treated have various problems in their addictiveness and drug stability; thus, it is recommended that efficacy and safety should be secured through simultaneous prescription of multiple drugs rather than a single drug treatment. Accordingly, it is necessary to develop drugs that newly target pathogenic mechanisms of ADHD. In this study, we attempt to confirm the possibility of developing new drugs by reviewing dopamine-related developmental mechanisms of neurons and their correlation with ADHD. Histone deacetylase inhibitors (HDACi) can regulate the concentration of intracellular dopamine in neurons by expressing vesicular monoamine transporter 2 and inducing the exocytosis of neurotransmitters to the synaptic cleft, thereby promoting the development of neurons and signal transmission. This cellular modulation of HDACi is expected to treat ADHD by regulating endogenous catecholamines such as dopamine. Although studies are still in the preclinical stage, HDAC inhibitors clearly have potential as a therapeutic agent with low addictiveness and high efficacy for ADHD treatment.

Vitamin C promotes the early reprogramming of fetal canine fibroblasts into induced pluripotent stem cells

  • Sang Eun Kim;Jun Sung Lee;Keon Bong Oh;Jeong Ho Hwang
    • 한국동물생명공학회지
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    • 제38권4호
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    • pp.199-208
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    • 2023
  • Background: Canine induced pluripotent stem cells (iPSCs) are an attractive source for veterinary regenerative medicine, disease modeling, and drug development. Here we used vitamin C (Vc) to improve the reprogramming efficiency of canine iPSCs, and its functions in the reprogramming process were elucidated. Methods: Retroviral transduction of Oct4, Sox2, Klf4, c-Myc (OSKM), and GFP was employed to induce reprogramming in canine fetal fibroblasts. Following transduction, the culture medium was subsequently replaced with ESC medium containing Vc to determine the effect on reprogramming activity. Results: The number of AP-positive iPSC colonies dramatically increased in culture conditions supplemented with Vc. Vc enhanced the efficacy of retrovirus transduction, which appears to be correlated with enhanced cell proliferation capacity. To confirm the characteristics of the Vc-treated iPSCs, the cells were cultured to passage 5, and pluripotency markers including Oct4, Sox2, Nanog, and Tra-1-60 were observed by immunocytochemistry. The expression of endogenous pluripotent genes (Oct4, Nanog, Rex1, and telomerase) were also verified by PCR. The complete silencing of exogenously transduced human OSKM factors was observed exclusively in canine iPSCs treated with Vc. Canine iPSCs treated with Vc are capable of forming embryoid bodies in vitro and have spontaneously differentiated into three germ layers. Conclusions: Our findings emphasize a straightforward method for enhancing the efficiency of canine iPSC generation and provide insight into the Vc effect on the reprogramming process.

삼용부정탕(蔘茸扶正湯)의 방사선(放射線) 조사(照射)로 손상(損傷)된 조직(組織) 회부(恢復) 및 조혈촉진(造血促進) 효과(效果) (Hemopoietic and Radioprotective Effects of Shenrong Fuzheng Tang(S.F.T.;蔘茸扶正湯))

  • 김정수;최승훈;안규석
    • 대한한방종양학회지
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    • 제3권1호
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    • pp.129-147
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    • 1997
  • 현재 서양의학에서 활용되고 있는 항암 요법으로는 외과처치(外科處置), 화학요법(化學療法), 방사선요법(放射線療法) 및 면역요법(免疫療法) 등(等)이 있으며, 그 중에서도 항암제(抗癌劑)에 의한 화학요법과 방사선요법이 가장 많이 응용되고 있다. 그런데 이들은 암세포(癌細胞)뿐만 아니라 정상세포(正常細胞)까지도 살상(殺傷)함으로써 종양세포(腫瘍細胞)를 억제하는 동시에 골수조혈기(骨髓造血器), 소화계통(消化系統) 및 면역기능(免疫機能)을 포함하는 인체의 정상적인 기능을 손상시키는 문제점으로 그 사용에 제한을 받고 있다. 따라서, 본 연구는 삼용부정탕(蔘茸扶正湯)의 항암요법으로 손상된 조직의 회복 및 조혈촉진 효과를 규명하기 위해 생쥐를 대상으로 하여 실험하였다. 그 결과, 생쥐 비장세포에 대한 증식효과(增殖效果), 조혈촉진인자(造血促進因子)의 분필능(分泌能), 방사선에 대한 임파구의 방어효과(防禦效果), 방사선에 대한 조혈세포 방어효과(防禦效果), 방사선(9Gy)을 조사받은 생쥐의 생존율(生存率) 등에서 유의성 있는 결과를 얻어내어 아래와 같이 보고하는 바이다.

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동의보감(東醫寶鑑) 중(中) 지각(枳殼)이 주약(主藥)으로 배오(配伍)된 방제(方劑)의 활용(活用)에 대한 고찰(考察) (A study on Applications of prescriptions including Fructus Ponciri Seu Aurantii as a main component in Dongeuibogam)

  • 유승훈;임영환;유승열;윤용갑
    • 대한한의학방제학회지
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    • 제16권1호
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    • pp.15-27
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    • 2008
  • This report describes 46 studies related to the use of Fructus Ponciri Seu Aurantii main blended prescriptions from Dongeuibogam. The following conclusions were reached through investigations on the prescriptions that use Fructus Ponciri Seu Aurantii as a key ingredient. 1. 19.6% of feces recorded the largest number of clinical frequency of the prescriptions in therapeutic use when Fructus Ponciri Seu Aurantii was taken as a monarch drug in prescriptions. In addition, 13.0% of each of a cough and an abdominal mass with distention and pain ranked second. 2. Prescriptions that utilize Fructus Ponciri Seu Aurantii as the main ingredient are used in the treatmeant of 5 diseases related to each of feces and an abdominal mass with distention and pain, and they are also used for treating different types of diseases related to the following ; a cough, a chest, ribs, eyes, the fullness in the chest, Qi, skin areas. 3. In the view of the causative agent of a disease, the prescriptions which are compounded with Fructus Ponciri Seu Aurantii as a monarch drug are related to endogenous agents such as seven emotion, food, deficiency, exogenous agents such as wind-cold pathogen, heat and non-endo-exopathogcnic factors like diseases due to external factors, poison. And in the view of the pathology of a disease, they are applied to the viscera pathology related to the lung, the spleen and stomach, the pathology of Qi and blood related to the reversed flow of Qi, the congestion of Qi, the deficiency of blood, the obstruction of Qi and blood, and the pathology about the retention of phlegm and fluid related to phlegm stagnation. 4. The dosage of Fructus Ponciri Seu Aurantii is 1.25pun(about 0,47g) to 2jeon(about 7.5g), however 1jeon(about 3.75g) has been taken the most for clinical application. 5. We can find out that according to herbs or prescriptions blended with itself, Fructus Ponciri Seu Aurantii makes a variety of functions to penetrate and remove stagnation, regulate Qi flow, relieve stagnation, expell wind and get rid of pain.

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회전교차로 주행 만족도 및 안전성 평가 (Driving Satisfaction and Safety Assessment for Roundabout)

  • 남궁문;신회식;장태연
    • 대한토목학회논문집
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    • 제34권1호
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    • pp.223-233
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    • 2014
  • 본 연구는 도로 교통전문가에 대한 개인속성 및 운전행태를 비롯한 회전교차로 주행경험에 따른 만족도에 영향을 미칠 것으로 예상되는 요인들을 분석하였다. 회전교차로의 주행환경 만족도 특성을 명확하게 규명하기 위해 주성분분석을 실시하여 구성요인을 추출하고 변수들을 3개의 요인으로 그룹화하였으며, 각 그룹을 만족요인속성, 운전행태속성, 개인속성으로 명명하였다. 변수들의 신뢰성과 타당성을 검증하기 위해 확인적 요인분석을 통하여 변수정제과정을 거친 후 회전교차로 주행성 인지와 만족요인속성을 내생잠재변수로, 개인속성과 운전행태속성을 외생잠재변수로 구조화한 회전교차로 주행환경 만족도 모형을 개발하였다. 모형 추정결과, 회전교차로 주행만족도는 차량지체 감소, 교통안전성 향상, 도로용량 증대, 도시미관 개선, 교통환경 개선, 심각사고 감소, 자전거 이용 편의 등 만족요인속성에 직접적인 영향을 받으며 성별, 연령, 운전시간, 운전경력 등 개인속성에 간접적인 영향을 받는 것으로 분석되었다. 교통법규 준수, 양보운전, 교통표지 준수, 끼어들기 운전 등 운전행태속성은 주행 만족도에 통계적으로 유의한 영향을 끼치지 못하였다. 그리고 AHP분석결과, 회전교차로 안전성 확보를 위해서는 기하구조의 회전반경과 운전자특성의 운전습관이 가장 중요한 요소로 선정되었다.

Genetic Polymorphisms of UGT1A and their Association with Clinical Factors in Healthy Koreans

  • Kim, Jeong-Oh;Shin, Jeong-Young;Lee, Myung-Ah;Chae, Hyun-Suk;Lee, Chul-Ho;Roh, Jae-Sook;Jin, Sun-Kyung;Kang, Tae-Sun;Choi, Jung-Ran;Kang, Jin-Hyoung
    • Genomics & Informatics
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    • 제5권4호
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    • pp.161-167
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    • 2007
  • Glucuronidation by the uridine diphosphateglucuronosy-ltransferase 1A enzymes (UGT1As) is a major pathway for elimination of particular drugs and endogenous substances, such as bilirubin. We examined the relation of eight single nucleotide polymorphisms (SNPs) and haplotypes of the UGT1A gene with their clinical factors. For association analysis, we genotyped the variants by direct sequencing analysis and polymerase chain reaction (PCR) in 218 healthy Koreans. The frequency of UGT1A1 polymorphisms, -3279T>G, -3156G>A, -53 $(TA)_{6>7}$, 211G>A, and 686C>A, was 0.26, 0.12, 0.08, 0.15, and 0.01, respectively. The frequency of -118 $(T)_{9>10}$ of UGT1A9 was 0.62, which was significantly higher than that in Caucasians (0.39). Neither the -2152C>T nor the -275T>A polymorphism was observed in Koreans or other Asians in comparison with Caucasians. The -3156G>A and -53 $(TA)_{6>7}$ polymorphisms of UGT1A were significantly associated with platelet count and total bilirubin level (p=0.01, p=0.01, respectively). Additionally, total bilirubin level was positively correlated with occurrence of the UGT1A9-118 $(T)_{9>10}$ rare variant. Common haplotypes encompassing six UGT1A polymorphisms were significantly associated with total bilirubin level (p=0.01). Taken together, we suggest that determination of the UGT1A1 and UGT1A9 genotypes is clinically useful for predicting the efficacy and serious toxicities of particular drugs requiring glucuronidation.

藏府와 身形의 病機 및 病症에 대한 比較考察 (Comparative study on patterns and symptoms of disharmony(病機病症) between the internal organs(藏府) and external bodily form(身形))

  • 백상룡
    • 대한한의학원전학회지
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    • 제13권2호
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    • pp.21-21
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    • 2000
  • All living things including human being consist of soul(spirit) and body. Soul is the root of a life and body frames it. I wrote this paper to tell how internal injury due to endogenous etiological factors and affection due to exegenous pathogenic factors, affect the internal organs and the external bodily from. This paper begins with description of the patterns of disharmony of the internal organs. General disorders of each Five-Jang(五藏) an be classified into two types of soul and body. The Liver and the Heart which lead changing to Yang(陽) of vital energy, have close relationship with spiritual symptoms because spirit is related to Yang. The Lung, Kidneys, the Spleen which lead changing to m(陰) of vital energy, mainly connected with physical disorders because body is relatively close to m. The Five-Jang are ruled by the Five-Phases(五行) system and cause troubles with Oche(五體) and the nine body orifice. Otherwise the main function of the Six-Bu(六府) is to receive food, absorb the usuable portions, and transmit and excrete waste. Therefore they can cause such problems as abdominal pain, distention, difficulty in urination, and constipation. The spleen is responsible for sending Grain-Ki)穀氣) 내 that is closely connected with the six-Bu. The Gall bladder takes care of control of giving out spirit. That's why it presents many symptoms related to the spirit that is ruled by the Five-Jang. Patterns of disharmony of external bodily form is influenced by the state of Maridians. Bodily forms get divided into many parts by the function of six-meridians(六經) to which they belong. Six-meridians have their own function related to excretion, related to excretion, retention, and balance(開闔樞). If local bodily froms get affected by pernicious influences, the Meridians to which they are attached will lose harmony and connot fulfil their own functions. Because the meridian symtem unifies all parts of the body, the whole body will be under the influence of the affection although local parts of the bodily forms get affected. Therefore the symptoms of disharmony should be considered in a synthetic view. There are however, also cases which should be focused on the very meridian channels affected. Disorder within a Meridian generates derangement in the pathway make it not to benefit the muscles and skin belong to it. Because the meridians connect the interior organs with the exterior bodily form, they are influenced by each other.

장부(藏府)와 신형(身形)의 병기(病機) 및 병증(病症)에 대한 비교고찰(比較考察) (Comparative study on patterns and symptoms of disharmony(病機病症) between the internal organs(藏府) and external bodily form(身形))

  • 백상룡
    • 대한한의학원전학회지
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    • 제13권2호
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    • pp.22-42
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    • 2000
  • All living things including human being consist of soul(spirit) and body. Soul is the root of a life and body frames it. I wrote this paper to tell how internal injury due to endogenous etiological factors and affection due to exogenous pathogenic factors, affect the internal organs and the external bodily from. This paper begins with description of the patterns of disharmony of the internal organs. General disorders of each Five-Jang(五藏) an be classified into two types of soul and body. The Liver and the Heart which lead changing to Yang(陽) of vital energy, have close relationship with spiritual symptoms because spirit is related to Yang. The Lung, Kidneys, the Spleen which lead changing to m(陰) of vital energy, mainly connected with physical disorders because body is relatively close to m. The Five-Jang are ruled by the Five-Phases(五行) system and cause troubles with Oche(五體) and the nine body orifice. Otherwise the main function of the Six-Bu(六府) is to receive food, absorb the usable portions, and transmit and excrete waste. Therefore they can cause such problems as abdominal pain, distention, difficulty in urination, and constipation. The spleen is responsible for sending Grain-Ki(穀氣) so that is closely connected with the six-Bu. The Gall bladder takes care of control of giving out spirit. That's why it presents many symptoms related to the spirit that is ruled by the Five-Jang. Patterns of disharmony of external bodily form is influenced by the state of Meridians. Bodily forms get divided into many parts by the function of six-meridians(六經) to which they belong. Six-meridians have their own function related to excretion, related to excretion, retention, and balance(開闔樞). If local bodily forms get affected by pernicious influences, the Meridians to which they are attached will lose harmony and cannot fulfil their own functions. Because the meridian system unifies all parts of the body, the whole body will be under the influence of the affection although local parts of the bodily forms get affected. Therefore the symptoms of disharmony should be considered in a synthetic view. There are however, also cases which should be focused on the very meridian channels affected. Disorder within a Meridian generates derangement in the pathway make it not to benefit the muscles and skin belong to it. Because the meridians connect the interior organs with the exterior bodily form, they are influenced by each other.

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