• Title/Summary/Keyword: Evidence base

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Gold and Silver Mineralization in the Yonghwa Mine (용화광산(龍化鑛山)의 금은광화작용(金銀鑛化作用))

  • Youn, Seok-Tai;Park, Hee-In
    • Economic and Environmental Geology
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    • v.24 no.2
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    • pp.107-129
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    • 1991
  • The Yonghwa gold-silver deposits are emplaced along $N15^{\circ}{\sim}25^{\circ}W$ trending fissures in middle Cretaceous porphyritic granite or Precambrian Sobaegsan gneiss complex. The results of paragenetic studies suggest that vein filling can be subdivided into four identifiable stages; state I: the main sulfide stage, characterized by base-metal sulfide minerals, iron oxides and minor electrum, stage II: electrum stage, stage III: electrum and silver-bearing sulfosalts stage, stage IV: post ore stage of carbonates and quartz. The ore mineralogy suggests that depositional temperature of the formation of the gold and silver minerals are estimated as 200 to $250^{\circ}C$ and 140 to $180^{\circ}C$, respectively. Sulfur fugacity of the formation of the gold and silver minerals are estimated as $10^{-14.0}$ to $10^{-12.2}$ atm and $10^{-18.5}$ to $10^{-17.2}$ atm, respectively. A consideration of the pressure regime during ore deposition bases on the fluid inclusion evidence of boiling suggests lithostatic pressure of less than 180 bars. This range of pressure indicate that vein system lay at depth of 700m below the surface at the time during mineralization. Salinities of ore-bearing fluids range from 0.4 to 6.9 wt.% equivalent NaCl. The sulfur and carbon isotopic data reveal that these elements were probably derived from a deep-seated source. The ${\delta}^{18}O$ of the hydrothermal fluid was determined from ${\delta}^{18}O$ values of quartz and calcite. Oxygen and hydrogen isotopic studies reveal that meteoric water dominate over ore-bearing fluid.

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Log Usage Analysis: What it Discloses about Use, Information Seeking and Trustworthiness

  • Nicholas, David;Clark, David;Jamali, Hamid R.;Watkinson, Anthony
    • International Journal of Knowledge Content Development & Technology
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    • v.4 no.1
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    • pp.23-37
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    • 2014
  • The Trust and Authority in Scholarly Communications in the Light of the Digital Transition research project1) was a study which investigated the behaviours and attitudes of academic researchers as producers and consumers of scholarly information resources in respect to how they determine authority and trustworthiness. The research questions for the study arose out of CIBER's studies of the virtual scholar. This paper focuses on elements of this study, mainly an analysis of a scholarly publisher's usage logs, which was undertaken at the start of the project in order to build an evidence base, which would help calibrate the main methodological tools used by the project: interviews and questionnaire. The specific purpose of the log study was to identify and assess the digital usage behaviours that potentially raise trustworthiness and authority questions. Results from the self-report part of the study were additionally used to explain the logs. The main findings were that: 1) logs provide a good indicator of use and information seeking behaviour, albeit in respect to just a part of the information seeking journey; 2) the 'lite' form of information seeking behaviour observed in the logs is a sign of users trying to make their mind up in the face of a tsunami of information as to what is relevant and to be trusted; 3) Google and Google Scholar are the discovery platforms of choice for academic researchers, which partly points to the fact that they are influenced in what they use and read by ease of access; 4) usage is not a suitable proxy for quality. The paper also provides contextual data from CIBER's previous studies.

A Study of Using the Car's Black Box to generate Real-time Forensic Data (자동차의 블랙박스를 이용한 실시간 포렌식 자료 생성 연구)

  • Park, Dea-Woo;Seo, Jeong-Man
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.1
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    • pp.253-260
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    • 2008
  • This paper is based on the ubiquitous network of telematics technology, equipped with a black box to the car by a unique address given to IPv6. The driver's black box at startup and operation of certification, and the car's driving record handling video signals in real-time sensor signals handling to analyze the records. Through the recorded data is encrypted transmission, and the Ubiquitous network of base stations, roadside sensors through seamless mobility and location tracking data to be generated. This is a file of Transportation Traffic Operations Center as a unique address IPv6 records stored in the database. The car is equipped with a black box used on the road go to Criminal cases, the code automotive black boxes recovered from the addresses and IPv6, traffic records stored in a database to compare the data integrity verification and authentication via secure. This material liability in the courtroom and the judge Forensic data are evidence of the recognition as a highly secure. convenient and knowledge in the information society will contribute to human life.

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The Impact of Workplace Democracy on Social Capital: The Moderating Effect of Servant Leadership (조직 내 민주성이 사회적 자본의 형성에 미치는 영향: 서번트 리더십의 조절효과)

  • LI, Yiran;SONG, Kwancheol
    • The Journal of Industrial Distribution & Business
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    • v.10 no.7
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    • pp.59-69
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    • 2019
  • Purpose - Unlike in the past, individualistic thought is more dominant than groupism where members prioritize organizations. Such changes run counter to the direction of the survival of the companies, which calls for companies to explore strategies to address thems. As one of the solutions, many people highlights social capital. However, since most studies have been conducted on the definition and characteristics of social capital, there is not enough prior factor research on the formation of social capital. So the current situation require researches on the formation of social capital. Research design, data, and methodology - To achieve the purpose, the literature and the empirical studies were combined. Deriving workplace democracy and servant leadership as factors affecting the formation of social capital through the literature, and this factors have modeled assumptions about the impact on social capital, and have established hypotheses to verify them. The survey which is conducted to verify the hypothesis and questionnaires are derived base on the variables used in the previous studies. The survey was conducted 447 respondents in Korea. Results - As a result, we found that the workplace democracy is positively functioning with the formation of social capital. It means that the democracy functions as a universal element to enhance the quality of social capital at the workplace. The evidence also shows that the positive impacts of the servant leadership on the formation of social capital. And the survey shows that groups with high level servant leadership had a higher impact on the formation of social capital than those with low levels leadership. Conclusions - At present, the social capital has become an important factor for the companies pursuing high performance workplaces. We found that the workplace democracy and the servant leadership affect the formation of social capital. It means that to increase the employees' sense of community and solidarity, it is need to form democratic environment with the servant leadership. Therefore, based on the results of this study, the workplace democracy and the servant leadership can present strategic implications that can increase the social capital.

Evidence for a Common Molecular Basis for Sequence Recognition of N3-Guanine and N3-Adenine DNA Adducts Involving the Covalent Bonding Reaction of (+)-CC-1065

  • Park, Hyun-Ju
    • Archives of Pharmacal Research
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    • v.25 no.1
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    • pp.11-24
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    • 2002
  • The antitumor antibiotic (+)-CC-1065 can alkylate N3 of guanine in certain sequences. A previous high-field $^1H$ NMR study on the$(+)-CC-1065d[GCGCAATTG*CGC]_2$ adduct ($^*$ indicates the drug alkylation site) showed that drag modification on N3 of guanine results in protonation of the cross-strand cytosine [Park, H-J.; Hurley, L. H. J. Am. Chem. Soc.1997, 119,629]. In this contribution we describe a further analysis of the NMR data sets together with restrained molecular dynamics. This study provides not only a solution structure of the (+)-CC-1065(N3- guanine) DNA duplex adduct but also new insight into the molecular basis for the sequence- specific interaction between (+)-CC-1065 and N3-guanine in the DNA duplex. On the basis of NOESY data, we propose that the narrow minor groove at the 7T8T step and conformational kinks at the junctions of 16C17A and 18A19T are both related to DNA bending in the drugDNA adduct. Analysis of the one-dimensional $^1H$ NMR (in $H_2O$) data and rMD trajectories strongly suggests that hydrogen bonding linkages between the 8-OH group of the (+)-CC-1065 A-sub-unit and the 9G10C phosphate via a water molecule are present. All the phenomena observed here in the (+)-CC-1065(N3-guanine) adduct at 5'$-AATTG^*$are reminiscent of those obtained from the studies on the (+)-CC-1065(N3-adenine) adduct at $5'-AGTTA^*$, suggesting that (+)-CC-1065 takes advantage of the conformational flexibility of the 5'-TPu step to entrap the bent structure required for the covalent bonding reaction. This study reveals a common molecular basis for (+)-CC-1065 alkylation at both $5'-TTG^*$ and $5'-TTA^*$, which involves a trapping out of sequence-dependent DNA conformational flexibility as well as sequence-dependent general acid and general base catalysis by duplex DNA.

Excitatory Effect of $M_1$ Muscarinic Acetylcholine Receptor on Automaticity of Mouse Heart

  • Woo Sun-Hee;Lee Byung Ho;Kwon Kwang-Il;Lee Chin Ok
    • Archives of Pharmacal Research
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    • v.28 no.8
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    • pp.930-935
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    • 2005
  • We have investigated the effects of relatively high concentration of carbachol (CCh), an agonist of muscarinic acetylcholine receptor (mAChR), on cardiac automaticity in mouse heart. Action potentials from automatically beating right atria of mice were measured with conventional microelectrodes. When atria were treated with $100{\mu}M$ CCh, atrial beating was immediately arrested and diastolic membrane potential (DMP) was depolarized. After exposure of the atria to CCh for $\~4 min$, action potentials were regenerated. The regenerated action potentials had lower frequency and shorter duration when compared with the control. When atria were pre-exposed to pirenzepine $(1{\mu}M)$, an $M_1$ mAChR antagonist, there was complete inhibition of CCh-induced depolarization of DMP and regeneration of action potentials. Pre-exposure to AFDX-116 (11 ({2-[(diethylamino)-methyl]-1-piperidyl}acetyl)-5, 11-dihydro-6H-pyridol[2,3-b][1,4] benzodiazepine-6-one base, $1{\mu}M$), an $M_2$ mAChR antagonist, failed to block CCh-induced arrest of the beating. However, prolonged exposure to CCh elicited gradual depolarization of DMP and slight acceleration in beating rate. Our data indicate that high concentration of CCh depolarizes membrane potential and recovers right atrial automaticity via $M_1$ mAChR, providing functional evidence for the role of $M_1$ mAChR in the atrial myocytes.

Protective Effect of Sesaminol Glucosides on Memory Impairment and ${\beta}$, ${\gamma}$-Secretase Activity In Vivo (Sesaminol Glucosides의 기억력 회복능 및 ${\beta}$, ${\gamma}$-Secretase)

  • Lee, Sun-Young;Son, Dong-Ju;Ha, Tae-Youl;Hong, Jin-Tae
    • YAKHAK HOEJI
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    • v.49 no.2
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    • pp.168-173
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    • 2005
  • Alzheimers disease (AD) is the most prevalent form of neurodegenerations associated with aging in the human population. This disease is characterized by the extracellular deposition of beta-amyloid (A ${\beta}$) peptide in cerebral plaques. The A ${\beta}$ peptide is derived from the ${\beta}$-amyloid precursor protein ( ${\beta}$APP). Photolytic processing of ${\beta}$APP by ${\beta}$-secretase(beta-site APP-cleaving enzyme, BASE) and ${\gamma}$-secretase generates the A ${\beta}$ peptide. Several lines of evidence support that A ${\beta}$-induced neuronal cell death is major mechanisms of development of AD. Accordingly, the ${\beta}$-and ${\gamma}$-secretase have been implicated to be excellent targets for the treatment of AD. We previously found that sesaminol glucosides have improving effect on memory functions through anti-oxidative mechanism. In this study, to elucidate possible other mechanism (inhibition of ${\beta}$-and ${\gamma}$-secretase) of sesaminol glucosides, we examined the improving effect of sesaminol glucosides in the scopolamine (1 mg/kg/mouse)-induced memory dysfunction using water maze test in the mice. Sesaminol glucosides (3.75, 7.5 mg/kg/6ml/day p.o., for 3 weeks) reversed the latency time, distance and velocity by scopolamine in dose dependent manner. Next, ${\beta}$-and ${\gamma}$-secretase activities were determined in different regions of brain. Sesaminol glucosides dose-dependently attenuated scopolamine-induced ${\beta}$-secretase activities in cortex and hippocampous and ${\gamma}$-secretase in cortex. This study therefore suggests that sesaminol glucosides may be a useful agent for prevention of the development or progression of AD, and its inhibitory effect on secretase may play a role in the improving action of sesaminol glucosides on memory function.

Intensifiers in Korean, English and German: Focusing on their non-head-bound-use (한국어, 영어 그리고 독일어의 강화사: 비결속 용법을 중심으로)

  • 최규련
    • Language and Information
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    • v.7 no.2
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    • pp.31-58
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    • 2003
  • The main goal of this paper is to describe and analyse intensifiers, especially non-head-bound-intensifiers (NHBIs), which can be included in the discussion and analysis of these elements as focus particles. In doing so, NHBIs such as Korean susulo, casin/cache, English x-self and German selbst are dealt with in a rather cross-linguistical perspective. The pure and strict comparison between Korean, English and German is not intended. This paper is mainly concerned with the semantic domain where the respective contributions of the expressions in question overlap, which offers the common base for the discussion regarding Korean, one of the non-European languages and English and German, two European languages. They share the semantic domain ‘intensification’ regarding relevant subject-NP. They introduce an ordering distinguishing center and periphery. In contrast to head-bound-intensifiers (HBIs), however, NHBIs add self-involvement (directness of involvement) of subject-NP to the meaning of the relevant sentence. I adopt the proposals of Konig (1991), Primus (1992) and Siemund (2000) in the treatment of intensifiers as focus particles. However, I reject Konig (1991) that just NHBIs talre scope over a whole clause, Primus (1992) that NHBIs focus VPs, not NPs, and Siemund (2000) that NHBIs can be further devided into two groups, viz. NHBIs with exclusive readings and NHBIs with inclusive readings. Evidence for my position is presented mainly in the course of describing and analysing some syntactic properties and the meaning and use of NHBIs. I come to the conclusion that both the common meaning of intensifiers as focus particles and the common meaning of NHBIs of three languages can be represented by a simple logical formalism.

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A Case of Locally Invasive and Recurred Papillary Thyroid Carcinoma Metastatizing to Cervical Lymphatic Chains and Mediastinum (광범위한 국소재발 및 경부, 종격동 전이를 동반한 유두상 갑상선암 1례)

  • Choi Hong-Shik;Lee Ju-Hyoung;Kim Jae-Won;Yang Hae-Dong
    • Korean Journal of Head & Neck Oncology
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    • v.13 no.1
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    • pp.62-68
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    • 1997
  • The papillary carcinoma is the most common malignant neoplasm of thyroid gland and the prognosis is better than anyother type of thyroid carcinoma. However, the thyroid is closed to the important organs such as esophagus, trachea and larynx, there are some possibilities to invade these organs. In case of advanced disease, not only surrounding structures but also mediastinum and cervical lymphatic chain can be involved or distant metastasis develops frequently. Therefore in these cases the prognosis is worse and the rate of inoperable case is more than those of non-metastatic group. Generally, the treatment modality for papillary thyroid carcinoma consists of surgery, postoperative thyroid hormone and radioiodine therapy. If the tumor invades surrounding structures, cervical lymph node or mediastinum, total thyroidectomy and wide excision of tumor invaded area including mediastinal dissection and neck dissection is necessary. Recently, the authors have experienced a case of locally invasive and recurred papillary thyroid carcinoma without treatment for 7 years. The patient was performed previously thyroid lobectomy and isthmusectomy 13 years ago. We had determinded surgical therapy for this patient and performed mass excision with overlying skin, completion total thyroidectomy, right type I modified radical neck dissection, left lateral neck dissection, thoracotomy with supramediastinal dissection, shaving of diffusely involved trachea and skin defect reconstruction with pectoralis major myocutaneous flap. After operation 2 cycles of radioiodine therapy were taken. Now the patient is following up at the outpatient base and no evidence of disease state for postoperative 16 months. So we report on this case with a brief review of literature.

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Estimated Isoflavone Intake from Soy Products in Korean Middle-aged Women (한국 중년여성의 대두식품을 통한 이소플라본 섭취 수준 조사)

  • Lee, Soo-Kyung;Lee, Min-June;Yoon, Sun;Kwon, Dae-Joong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.5
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    • pp.948-956
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    • 2000
  • There is growing evidence that soy isoflavone play beneficial roles in the prevention of chronic diseases such as hormone dependent cancers, cardiovascular diseases, osteoporosis and also reduced incidence of menopausal symptoms. However current data are not sufficient to determine the effective doses for beneficial as well as harmful effects and to support dietary recommendation for isoflavones. Since soy products containing isoflavone are one of the common food items that Koreans consume daily basis, assessing consumption of soy isoflavone by Koreans will give a valuable information on making dietary recommendations for isoflavones. the present study was designed to assess dietary intake of isoflavone of Korean middle-aged women who might receive the most beneficial effects from isoflavone consumption thereby prevent post menopausal related symptoms and diseases. In this study isoflavone contents of soy products were analyzed and soy products and isoflavone consumption of these subjects were assessed by a self-reported dietary questionnaire and isoflavone intake data base. Subjects were consisted of 178 Korean women (35~60 y) who live in urban and rural area. All subjects provided detailed information on demographics, anthropometry, health history, menopausal symptoms, health history, menopausal symptoms, and dietary intake using food frequency questionnaire (FFQ) which was developed for Koreans. The average age of the subjects was 46.6 years. The soy products which the subjects frequently consumed were soybean paste soup, braised fried soybean, tofu residue stew, tofu, soy milk, natto stew, bean sprouts, and soybean broth which contained 10.68 mg, 3.34 mg, 2.44 mg, 2.42 mg, 2.42 mg, 1.12 mg, 1.02 mg, 0.33 mg of isoflavone per 100 g, respectively. The estimated daily intake (EDI) of isoflavones ranged from 0 to 144.3 mg, and the mean daily isoflavone (sum of daidzein and genisten) intake of the subjects was 24.41 mg.

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