• Title/Summary/Keyword: Spontaneous activity

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Isolation and Characterization of Pyrimidine Auxotrophs from the Hyperthermophilic Archaeon Sulfolobus acidocaldarius DSM 639 (Sulfolobus acidocaldarius 균주로부터 피리미딘 영양요구주의 분리 및 특성 연구)

  • Choi, Kyoung-Hwa;Cha, Jae-Ho
    • Journal of Life Science
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    • v.21 no.10
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    • pp.1370-1376
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    • 2011
  • To study the functional genomic analysis of a crenachaeon Sulfolobus acidocaldarius, we have constructed an auxotrophic mutant based on pyrEF, which encodes the pyrimidine biosynthetic enzymes orotate phosphoribosyltransferase and orotidine-5'-monophosphate decarboxylase. S. acidocaldarius was shown to be sensitive to 5-fluoroorotic acid (5-FOA), which can be selected for mutations in pyrEF genes within a pyrimidine biosynthesis cluster. Spontaneous 5-FOA-resistant mutants by ultraviolet, KH1U and KH2U, were found to contain two point mutations and a frame shift mutation in pyrE, respectively. Mutations at these sites from KH1U and KH2U decreased the activity of orotate phosphoribosyltransferase encoded by the pyrE gene and blocked the degradation of 5-FOA into toxic 5-FOMP and 5-FUMP that kill the cells. Therefore, KH1U and KH2U were uracil auxotrophs. Transformation of Sulfolobus-Escherichia coli shuttle vector pC bearing pyrEF genes from S. solfataricus P2 into S. acidocaldarius mutant KH2U restored 5-FOA sensitivity and overcame the uracil auxotrophy. This study establishes an efficient genetic strategy towards the systematic knockout of genes in S. acidocaldarius.

An Analysis on The National Project to Promote Management of Private Forest Management Cooperatives : Actual State of Its Management and Cognition of Its Members (협업체(協業體) 운영(運營)에 대한 참여산주(參與山主)들의 인식(認識)과 정책적(政策的) 추진실태(推進實態)에 관한 분석(分析))

  • Chung, Joo Sang;Park, Eun Sik;Kim, Kyu Hun
    • Journal of Korean Society of Forest Science
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    • v.85 no.3
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    • pp.487-495
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    • 1996
  • The objective of this study was to investigate the actual state of the national project to promote the management of Forest Management Cooperatives(FMC). To fulfil the objective, we have reviewed recent statistics, regulations, and publications related with FMC and interviewed officials and professionals engaged in FMC-related organizations. Also cognition of members on the actual state of the management of FMC's was studied by a questionnaire survey. The questionnaire was designed to get understandings of the general cognition of FMC's members associated with forest management and FMC's management activities. According to the results of the survey, more than 50% of members are not interested in forest management and most of them are not satisfied with the activity of FMC. In this paper, the results of analyses for the survey are discussed in detail. On the other hand, statistics indicate that the basic policy for FMC contributes to rapid growth in the number of local FMC's. However, the increase of FMC's has negative effect on management conditions of existing FMC's because of reduced budget allocation from the government. In addition, we concluded that some parts of current regulations for FMC are unfavorable in promoting the spontaneous management activities of local FMC's.

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Inhibitory Effect of NAD(P)H:Quinone Oxidoreductase 1 on the Activation of Macrophages (NQO1 (NAD(P)H:quinone oxidoreductase 1)에 의한 대식세포 활성화 억제)

  • Hong, Ji;Zhang, Peng;Yoon, I Na;Kim, Ho
    • Journal of Life Science
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    • v.27 no.8
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    • pp.873-878
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    • 2017
  • We previously reported that NAD(P)H:quinone oxidoreductase 1 (NQO1)-knockout (KO) mice exhibited spontaneous inflammation in the gut. We also found that NQO1-KO mice showed highly increased inflammatory responses compared with NQO1-WT control mice when subjected to DSS-induced experimental colitis. In a Clostridium difficile toxin-induced mouse enteritis model, NQO1-KO mice were also sensitive compared with NQO1-WT mice. Moreover, numerous studies have shown that NQO1 is functionally associated with immune regulation. Here, we assessed whether NQO1 defects can alter macrophage activation. We found that peritoneal macrophages isolated from NQO1-KO mice produced more IL-6 and $TNF-{\alpha}$ than those isolated from NQO1-WT mice. Moreover, the dicumarol-induced inhibition of NQO1 significantly increased IL-6 and $TNF-{\alpha}$ production in peritoneal macrophages isolated from NQO1-WT mice, as well as in the cultured mouse macrophage cell line, RAW264.7. These results indicate that NQO1 may negatively regulate the activation of macrophages. Knockout or chemical inhibition of NQO1 markedly reduced the expression of $I{\kappa}B$ (inhibitor of $NF{\kappa}B$) in both mouse peritoneal macrophages and RAW264.7 cells. Finally, RAW264.7 cells treated with dicumarol exhibited morphological changes reflecting macrophage activation. Our results suggest that NQO1 may suppress the $NF{\kappa}B$ pathways in macrophages, thereby suppressing the activation of these cells. Thus, immunosuppressive activity may be among the many possible functions of NQO1.

Changes in the Sensory Function after Transcranial Direct Stimulation on Dorsolateral Prefrontal Cortex Area (배외측전전두엽피질 영역에 경두개직류전류자극이 감각기능에 미치는 영향)

  • Min, Dong-Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.1
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    • pp.445-452
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    • 2015
  • Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers a low-intensity direct current to the cortical areas, thereby facilitating or inhibiting spontaneous neuronal activity. This study was designed to examine the changes in various sensory functions after tDCS. A single-center, single-blinded, randomized trial was conducted to determine the effect of a single session (August 4 to August 29) of tDCS with the current perception threshold (CPT) in 50 healthy volunteers. Nerve conduction studies (NCS) were performed in relation to the median sensory and motor nerves on the dominant hand to discriminate peripheral nerve lesions. The subjects received anodal tDCS with 1mA for 15 minutes under two different conditions, with 25 subjects in each group. The conditions were as follows: tDCS on the dorsolateral prefrontal cortex (DLPFC) and sham tDCS on DLPFC. The parameters of the CPT was recorded with a Neurometer$^{(R)}$ at frequencies of 2000, 250 and 5 Hz in the dominant index finger to assess the tactile sense, fast pain and slow pain, respectively. In the test to measure the CPT values of the DLPFC in the anodal tDCS group, the values increased significantly in all of 250 and 5 Hz. All CPT values decreased for the sham tDCS. These results showed that DLPFC anodal tDCS can modulate the sensory perception and pain thresholds in healthy adult volunteers. This study suggests that tDCS may be a useful strategy for treating central neurogenic pain in rehabilitation medicine.

Motor Imagery Brain Signal Analysis for EEG-based Mouse Control (뇌전도 기반 마우스 제어를 위한 동작 상상 뇌 신호 분석)

  • Lee, Kyeong-Yeon;Lee, Tae-Hoon;Lee, Sang-Yoon
    • Korean Journal of Cognitive Science
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    • v.21 no.2
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    • pp.309-338
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    • 2010
  • In this paper, we studied the brain-computer interface (BCI). BCIs help severely disabled people to control external devices by analyzing their brain signals evoked from motor imageries. The findings in the field of neurophysiology revealed that the power of $\beta$(14-26 Hz) and $\mu$(8-12 Hz) rhythms decreases or increases in synchrony of the underlying neuronal populations in the sensorymotor cortex when people imagine the movement of their body parts. These are called Event-Related Desynchronization / Synchronization (ERD/ERS), respectively. We implemented a BCI-based mouse interface system which enabled subjects to control a computer mouse cursor into four different directions (e.g., up, down, left, and right) by analyzing brain signal patterns online. Tongue, foot, left-hand, and right-hand motor imageries were utilized to stimulate a human brain. We used a non-invasive EEG which records brain's spontaneous electrical activity over a short period of time by placing electrodes on the scalp. Because of the nature of the EEG signals, i.e., low amplitude and vulnerability to artifacts and noise, it is hard to analyze and classify brain signals measured by EEG directly. In order to overcome these obstacles, we applied statistical machine-learning techniques. We could achieve high performance in the classification of four motor imageries by employing Common Spatial Pattern (CSP) and Linear Discriminant Analysis (LDA) which transformed input EEG signals into a new coordinate system making the variances among different motor imagery signals maximized for easy classification. From the inspection of the topographies of the results, we could also confirm ERD/ERS appeared at different brain areas for different motor imageries showing the correspondence with the anatomical and neurophysiological knowledge.

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Pharmacological Studies on Human Vas Deferens -Coexistence of Adrenergic and Cholinergic Receptors, and Effect of Diazepam- (인체 정관의 약리학적 검색 -아드레날린성 및 콜린성 수용체의 공존과 Diazepam의 작용-)

  • Kim, Won-Joon;Lee, Kwang-Youn;Ha, Jeoung-Hee;Park, Tong-Choon
    • The Korean Journal of Pharmacology
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    • v.24 no.2
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    • pp.189-195
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    • 1988
  • This study aimed to investigate the autonomic innervations of human vas deferens and the effect of diazepam, a benzodiazepine sedative antianxiety drug, on the smooth muscle contractility of vas deferens. The specimens were obtained from healthy volunteers undergoing elective vasectomy with local anesthesia. The muscle preparation did not show any spontaneous contraction, but showed a good contraction induced by norepinephrine exerting the strongest response at $33^{\circ}C$. Phentolamine inhibited the norepinephrine-induced contraction concentration-dependently. Isoproterenol, a beta-adrenergic agonist evoked a considerable extent of contraction, and this contractile activity was antagonized by propranolol, a beta-adrenergic blocking agent. Acetylcholine induced a dashing contraction of the human vas deferens, and atropine, a muscarinic receptor blocking agent abolished the acetylcholine-induced contraction. Diazepam inhibited the norepinephrine-induced contraction in a concentration dependent manner. These results suggest that the smooth muscle of human vas deferens has cholinergic muscarinic and beta adrenergic receptors as well as the predominant alpha adrepergic receptor. Diazepam inhibits the motility, especially norepinephrine-induced contraction of human vas deferens.

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The Effect of Motivation-Reward Fit on Commitment and Knowledge Sharing Activities in Communities of Practice (CoP(Community of Practice)에서 참여동기-보상 적합이 CoP 몰입과 지식공유활동에 미치는 영향)

  • Kim, In-Hak;Lee, Ji-Hyeon;Koh, Joon;Kim, Hee-Woong
    • The KIPS Transactions:PartD
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    • v.17D no.3
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    • pp.209-222
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    • 2010
  • As the business competition between firms is getting intense, one of the sources of competitive advantage is effectively and efficiently to create, share, and apply information/knowledge among employees. Most of the firms which conduct knowledge management are operating a Community of Practice(CoP) in order to create, share and utilize this kind of information/knowledge resource. Recently, the CoP is getting out of its informal and spontaneous manner and is beginning to be led by the top management, receiving official support, in order to achieve the organization's strategic goals. However, the corporation's strategic operation of the CoP is not only against its original characteristics but also hampers the spontaneity of its participants. Every participant has different motivation to participate and different preference for reward type. This study, with the survey of 114 respondents, found that intrinsic motivation as well as extrinsic motivation significantly affect the motivation-reward fitness. Also, the motivation-reward fit was found to influence CoP commitment which ultimately leads to knowledge sharing activity in the CoP context. This research will help knowledge management companies to figure out how the two things of participants' motivation and their reward types can fit together, and how such fitness ultimately affects the participants' commitment and their knowledge sharing activities.

THE NITROUS OXIDE CONCENTRATION IN BREATHING ZONE ACCORDING TO SCAVENGING METHODS DURING DEEP SEDATION OF PEDIATRIC DENTAL PATIENTS (소아치과 환자의 깊은 진정시 호기가스 제거 방법에 따른 호흡대역에서 Nitrous Oxide 농도 변화)

  • Lee, Chung-Won;Yoon, Hyung-Bae
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.1
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    • pp.124-131
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    • 2003
  • The concentration of nitrous oxide in dental environment has increased especially in pediatric department. In pediatric department frequently met the behavior disordered patients who need the deep sedation. As the deeply sedated patients could not respond well to verbal command, the amount of mouth breathing would be increased especially with mouth prop which backward transposition of mandible. Inhalation of low concentration of nitrous oxide for a long duration has caused various side effects such as spontaneous abortion and inhibition of methionine synthetase activity which is harmful to DNA synthesis. For evaluation of factors of mouth breathing during deep sedation. The author measured the concentration of nitrous oxide in breathing zone by the change of the scavenging methods. One is drain the gas through the tail part of reservoir bag of Jackson Ree's system naturally. Another is scavenge from tail portion of reservoir bag with negative pressure. Last one is scavenge from nasal mask with negative pressure. The nitrous oxide concentration in breathing zone was the lowest in nasal part drainage but high above the recommended concentration of NIOSH. The order of nitrous concentration in breathing zone was: natural drainage, tail part with negative pressure, nasal part with negative pressure. This would reflect the order of resistance of nasal airway and showed the amount of mouth breathing. From the above experiment, the resistance of nasal airway by the increment of gas flow in corrugating tube and reservoir bag would be one of the causative factors of mouth breathing in deeply sedated patients.

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A Study on Urinary Incontinence of Elderly Women in a Community (노인여성의 요실금 실태)

  • Park, Ok-Hee;Kwon, In-Soo;Kang, Young-Sil
    • Women's Health Nursing
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    • v.7 no.4
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    • pp.536-546
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    • 2001
  • The purposes of this descriptive study were to identify the prevalence rate of urinary incontinence(UI) and the differences in frequency of incontinent and normal women by general characteristics, obstetrical history, and the conditional events for urinary incontinence of the elderly women in a community. By the results of this study, it is intended to provide nursing practice guidelines for incontinent women. The research design of this study was a preliminary descriptive study. The 173 subjects were 55 years old and over, and resided in a small city area. Data were collected from June 20 to July 20, 2001, by an interview or a self-report with questionaire. The questionaire was composed of items of general characteristics, obstetrical characteristics, and conditions of UI by the modified Henderickon's Stress Incontinence Scale(1981). The results were summariezed as follows: 1. The UI prevalence rate of the sample was 64.2%. Of the incontinent women, 31.5% had experienced UI for a period of three to five years, and 84.7% had never treated or managed their UI. Frequency of UI was once or twice times per month(46.8%). 2. The total mean of UI on the scale in the incontinent women was 25.50 of 85, ranging from 18 to 41. 3. The most frequent condition of UI was coughing, followed by laughing, sneezing, heavy exercise, and preparation of urination in descending order. 4. There were significant differences in age, education, social activity, and urinary difficulty between the incontinent women and the normal women. 5. There were significant differences in frequency of spontaneous abortion, age of menopause between the incontinent women and the normal women. 6. There were no significant differences in number of delivery, frequency of artificial abortion, age of the last delivery, and postal health management between the incontinent women and the normal women. In conclusion, the incidence of UI in this study was high, but there were no effective treatments or management. It is suggested to provide the adult women with knowledge about UI, and to educate preventive behavior and control skill of urinary incontinence. Also episodes of urinary incontinence were high in the situation of sudden increase of abdominal pressure. This data can be used for the prevention strategy of urinary incontinence, In future research it is recommended to identify comprehensive factors related to urinary incontinence including psychosocial factors, and effective strategies of urinary incontinence.

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The Effects of Customer Participation in CSR(Corporate Social Responsibility) Process on Customers' Response (기업의 사회적 책임 활동 과정에서의 고객참여가 고객 반응에 미치는 영향)

  • Jang, Jung-Min;Lee, Eun-Young
    • Journal of Distribution Science
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    • v.14 no.3
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    • pp.45-54
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    • 2016
  • Purpose - There have been numerous studies investigating the effects of corporate social responsibility initiatives on corporate associations or corporate images. In line of this research stream, current research examined the potential impact of customer participation in the process of corporate social responsibility initiatives on attitude toward the company. This research differentiates from previous studies that it is the first to connect corporate social responsibility and customer participation. Specifically, we suggest a structural model on corporate associations which was classified into corporate ability associations and corporate social responsibility associations that the more the customers participate in initiating corporate social responsibility, corporate associations were formed more positively. And this leads to the increase of revisit intentions through customer satisfaction. Research design, data, and methodology - To test our research model, we collected data of real consumers of a large discount store in Korea. At the large discount store, customers were given an opportunity to participate the discount store's CSR activity program. We performed field survey and collected data of 146 respondents. We analyzed the data using PASW statistics 21.0 and AMOS 16.0 in order to test our structural model. Results - The results showed that consumers who participated more in initiating corporate social responsibility revealed higher score for corporate ability associations and corporate social responsibility associations. These corporate associations had a positive effect on customer satisfaction, which leads to higher attitude toward revisit intentions. Specifically, hypothesis 1.1 "As Customer participation in CSR process increases, the evaluation of CA associations will be positive,"was supported. Hypothesis 1.2 "As Customer participation in CSR process increases, the evaluation of CSR associations will be positive," was supported. Hypothesis 2.1 "As the evaluation of CA associations is positive, satisfaction with the firm will increase," was supported. Hypothesis 2.1 "As the evaluation of CSR associations is positive, satisfaction with the firm will increase," was supported. Hypothesis 3 "As satisfaction with the firm increases, revisit intentions with the firm will increase," was supported. Conclusions - This research is the first to study the relationship between customer participation in CSR process, CSR, and consumer reactions. This research also contributes to customer participation and corporate social responsibility literature by suggesting customer participation as an antecedent and empirically demonstrating the positive relationships between the constructs. The findings of this research may offer managerial implications for marketing practitioners. When performing corporate social initiatives, it is better to let the customer participate in the process which leads to higher corporate ability associations and corporate social responsibility associations, also higher satisfaction and revisit intentions. Our results provide useful information to practioners that spontaneous participation of consumers makes CSR initiatives effective and successful. Limitations and ideas for further research remain in this research. For example, our focus on the logic was cognitive evaluations(e.g. corporate associations) but affective dimensions might be considered since recent researches are investigating the relationship between customer participation and affective reaction as a response. Despite the limitations, this research have unique and applicable implications for academics and practitioners.