• Title/Summary/Keyword: Agent Management

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저품위 광석 또는 광미내 금 침출기술 현황 (Current Status of Gold Leaching Technologies from Low Grade Ores or Tailings)

  • 이상훈
    • 자원리싸이클링
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    • 제29권2호
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    • pp.3-7
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    • 2020
  • 최근 저품위 (폐)광석으로부터의 금 회수를 위한 침출기술이 각광을 받고 있다. 현재 침출기술은 경제성과 효율성 측면에서 시안을 이용하는 것이 효과적이나 시안은 독극물의 일종으로 환경오염의 우려가 있어 규제 및 관리가 요구된다. 특히 이러한 문제는 최근 주목받고 있는 저비용 침출기술인 Dump 혹은 Heap leaching 적용시 더욱 현저하다. 이를 해결하기 위해 티오황산염(thiosulfate) 이나 할로겐화합물 등 시안을 대체할 대안침출제의 개발이 활발하게 진행되고 있으나 이들은 아직 상용화에 이르기까지 여러 어려움이 있으며 추가적인 연구개발이 필요하다. 저비용 친환경적인 생물학적 금침출도 상용화되고 있으나 이는 대부분 직접 금 침출이 아닌 시안침출의 전처리 산화공정(pre-oxidation process)으로 적용되고 있다. 그러나 생물학적 침출을 통한 직접 금 회수도 이론적으로 가능하며 향후 Dump나 heap bioleaching을 통한 직접 금 침출로 시안이 필요없는 저품위 금 회수 상용화가 시급하다고 판단된다.

연구개발조직의 책임성에 관한 연구: '나로호' 발사체 사례를 중심으로 (A Study on the Accountability of Research and Development Organizations: Focused on the launch of the KSLV-I)

  • 조성식;권기훈;김동현
    • 기술혁신학회지
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    • 제15권1호
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    • pp.163-184
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    • 2012
  • 우리나라 최초 위성 발사체인 나로호의 사례에 대한 기술적 보고서들이 나오고 있지만 수많은 물 인적 자원이 투입된 우주개발사업에서 왜 이러한 기술적인 문제가 두 번이나 발생하였는지에 대한 심층적인 연구는 아직 이루어지지 않고 있다. 이에 본 논문에서는 연구개발조직의 책임성이라는 관점에서 나로호 사례를 기술적 측면 이외에도 관리적 측면과 제도적 측면까지 검토하였다. 연구개발조직의 책임성에서 가장 중요한 부분은 전문적 책임성이며 정치적 상황 등으로 인해 소홀이 되었을 때 목표의 수행에 성공하기 어렵다는 사실을 확인하였다. 또한 책임소재 측면에 있어 러시아에게 천문학적인 돈을 지불하고 이용하는 입장인 우리나라가 러시아와 관련문제에 대해 분쟁을 벌이는 동안 주인으로서 정당한 권리를 누리지 못한 원인을 주인과 대리인의 목표 불일치에서 찾고 재발방지를 위한 노력들을 살펴보았다.

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욕창 환자에서 자율신경성 반사부전증의 경험례 (Case Report of Autonomic Dysreflexia in a Pressure Sore Patient)

  • 남승민;박은수;박선아;김용배
    • Archives of Plastic Surgery
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    • 제34권4호
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    • pp.531-534
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    • 2007
  • Purpose: Plastic surgeons are responsible for the management of spinal cord injury patients with upper and lower extremity reconstruction, pressure sore, and wounds. Derailment of autonomic nervous systems caused by injury to the spinal cord may result in fatal autonomic dysreflexia. Autonomic dysreflexia is a syndrome of massive imbalance of reflex sympathetic discharge occurring in patients with spinal cord lesion above the splanchnic outflow(T6). It is characterized by a sudden onset and severe increase in blood pressure and is potentially life threatening. The other classic symptoms are headache, chest pain, sweating, and bradycardia. In order to lower the blood pressure, it is important to remove the noxious stimulus for autonomic dysreflexia. If such symptoms last for more than 15 minutes despite conservative interventions, antihypertension drugs are recommended. Methods: In this case study, we report an autonomic dysreflexia case that developed in a 45 year-old tetraplegia patient with sacral pressure sore. When he got bladder irrigation, his blood pressure went up very high and his mentality became stuporous. He was sent to ICU for his blood pressure and mental care. ICU care made his vital sign stabilized and his mentality alert. Results: After the patient underwent proper treatment like inotropic agent, he was transferred to the general ward and his pressure sore on sacral area was coveraged with gluteus maximus myocutaneous advancement flap. Conclusion: If treatment is not effective, the patients have to undergo sudden, severe hypertension, which can cause stroke or death. To provide safe and effective care, plastic surgeons should be able to recognize and treat autonomic dysreflexia.

Biological Control of Gom-chwi (Ligularia fischeri) Phytophthora Root Rot with Enterobacter asburiae ObRS-5 to Suppress Zoosporangia Formation and Zoospores Germination

  • Kim, Dayeon;Lee, Sang Yeob;Ahn, Seong Ho;Han, Ji Hee;Park, Jin Woo
    • The Plant Pathology Journal
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    • 제36권3호
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    • pp.244-254
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    • 2020
  • Gom-chwi (Ligularia fischeri) is severely infected with Phytophthora drechsleri, the causal organism of Phytophthora root rot, an economically important crop disease that needs management throughout the cultivation period. In the present study, Phytophthora root rot was controlled by using bacterial isolates from rhizosphere soils collected from various plants and screened for antagonistic activity against P. drechsleri. A total of 172 bacterial strains were isolated, of which, 49 strains showed antagonistic activities by dual culture assay. In the seedling assay, six out of the 49 strains showed a predominant effect on suppressing P. drechsleri. Among the six strains, the ObRS-5 strain showed remarkable against P. drechsleri when treated with seed dipping or soil drenching. The ObRS-5 strain was identified as Enterobacter asburiae based on 16S ribosomal RNA gene sequences analysis. The bacterial cells of E. asburiae ObRS-5 significantly suppressed sporangium formation and zoospore germination in P. drechsleri by 87.4% and 66.7%, respectively. In addition, culture filtrate of E. asburiae ObRS-5 also significantly inhibited sporangium formation and zoospore germination by 97.0% and 67.6%, respectively. Soil drenched bacterial cells, filtrate, and culture solution of E. asburiae ObRS-5 effectively suppressed Phytophthora root rot by 63.2%, 57.9%, and 81.1%, respectively. Thus, E. asburiae ObRS-5 could be used as a potential agent for the biological control of Phytophthora root rot infecting gom-chwi.

시험관내에서 천연물제제 BSASM의 항염증 및 면역억제 효능 평가 (Evaluation of the Anti-inflammatory and Immunomodulatory Effects of BSASM Using in vitro Experiments)

  • 이종성;박유미;박병화;정광선;김국현;이원희;박덕훈
    • 생약학회지
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    • 제34권3호통권134호
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    • pp.228-232
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    • 2003
  • For effective management of atopic dermatitis, it is important to introduce a therapeutic agent although having the fewest side effects, has the greatest anti- inflammatory effect. In the course of screening anti-inflammatory agents, we obtained BSASM composed of several plant extracts. This study was designed to investigate anti-inflammatory and immunomodulatory effects of BSASM. As a first step, $NF-{\kappa}B$ luciferase reporter assay was performed to know the involvement of BSASM in the production of proinflammatory cytokines because $NF-{\kappa}B$ element has been known to play a major role in expression of cytokine genes such as interleukin-8 (IL-8) or tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$. LPS (lipolysaccharide)-induced $NF-{\kappa}B$ activation was inhibited by BSASM. In addition, we found the fact that BSASM inhibits LPS-induced produced production of IL-8 and $TNF-{\alpha}$ proinflammatory cytokines, indicating BSASM has anti-inflammatory effect. In interleukin-2 (IL-2) luciferase reporter assay in Jurkat T cells, BSASM reduced PHA (Phytohemagglutinin)-induced IL-2 luciferase activity, suggesting the possibility that BSASM might also have an immunomodulatory function in T cell-mediated immune response. Based on these results, we suggest the possibility that BSASM can be introduced to improve symptom of immune-related skin diseases, namely, atopic dermatitis.

입원환자에게 나타나는 섬망 아형별 위험요인과 증상 및 중재 분석 (Risk Factors, Symptoms, and Intervention Analysis of Delirium Subtypes in Hospitalized Patients)

  • 류아현;강영옥;송라윤
    • 한국융합학회논문지
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    • 제12권10호
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    • pp.353-363
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    • 2021
  • 본 연구는 입원환자 섬망의 아형별 위험요인, 증상 및 중재를 조사하기 위해 시행되었다. 상급종합병원에 입원한 뒤 섬망을 진단받은 환자 108명의 전자의무기록을 SPSS WIN 26.0 프로그램을 이용해 분석하였다. 분석결과, 대상자는 고령, 남성, 정형외과, 골절이나 절단 환자의 비율이 높았다. 섬망의 아형은 과활동형 51.9%, 저활동형 6.5%, 혼재형 41.7%이었다. 위험요인 중 우울과 향정신성 약물 복용은 저활동형 섬망군에게 더 많이 선행되었다. 섬망의 중재 중 행동문제 관리와 공격적 행동 중재는 과활동형, 혼재형 섬망군에게 주로 시행되었고 정서적 지지는 저활동형, 혼재형 섬망군에게 주로 시행되었다. 공격적 행동을 동반할 경우 즉각적으로 중재를 제공받을 가능성이 높았다. 따라서, 추후 입원환자의 섬망을 조기발견하고 중재할 수 있도록 중재전략과 프로토콜을 개발하기 위한 연구가 요구된다.

Molecular Cloning, Protein Expression, and Regulatory Mechanisms of the Chitinase Gene from Spodoptera littoralis Nucleopolyhedrovirus

  • Yasser, Norhan;Salem, Reda;Alkhazindar, Maha;Abdelhamid, Ismail A.;Ghozlan, Said A.S.;Elmenofy, Wael
    • 한국미생물·생명공학회지
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    • 제49권3호
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    • pp.305-315
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    • 2021
  • The cotton leafworm, Spodoptera littoralis, is a major pest in Egypt and many countries worldwide, and causes heavy economic losses. As a result, management measures to control the spread of the worm are required. S. littoralis nucleopolyhedrovirus (SpliNPV) is one of the most promising bioagents for the efficient control of insect pests. In this study, a chitinase gene (chitA) of a 1.8 kb DNA fragment was cloned and fully characterized from SpliNPV-EG1, an Egyptian isolate. A sequence of 601 amino acids was deduced when the gene was completely sequenced with a predicted molecular mass of 67 kDa for the preprotein. Transcriptional analyses using reverse transcription polymerase chain reaction (RT-PCR) revealed that chitA transcripts were detected first at 12 h post infection (hpi) and remained detectable until 168 hpi, suggesting their transcriptional regulation from a putative late promoter motif. In addition, quantitative analysis using quantitative RT-PCR showed a steady increase of 7.86-fold at 12 hpi in chitA transcription levels, which increased up to 71.4-fold at 120 hpi. An approximately 50 kDa protein fragment with chitinolytic activity was purified from ChitA-induced bacterial culture and detected by western blotting with an anti-recombinant SpliNPV chitinase antibody. Moreover, purification of the expressed ChitA recombinant protein showed in vitro growth inhibition of two different fungi species, Fusarium solani and F. oxysporum, confirming that the enzyme assembly and activity was correct. The results supported the potential role and application of the SpliNPV-ChitA protein as a synergistic agent in agricultural fungal and pest control programs.

LC-MS/MS를 이용한 조피볼락 근육에서 구충제 febantel 및 그 대사체들의 정량분석을 위한 시료 전처리 방법의 비교 분석 (Comparison of sample preparation methods for quantification of febantel, an anthelmintic agent, and its metabolites in rockfish (Sebastes schlegeli) muscle using liquid chromatography-tandem mass spectrometry)

  • 임재웅;권인영;김태호;김위식;강소영
    • 한국어병학회지
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    • 제34권2호
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    • pp.261-269
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    • 2021
  • This study presents the evaluation of sample extraction and purification procedure for the determination of residues of febantel and its metabolites, fenbendazole, oxfendazole and oxfendazole sulfone in rockfish (Sebastes schlegeli) muscle using liquid chromatography-tandem mass spectrometry. Residues of febantel and its metabolites in rockfish muscle were analyzed using each different sample preparation method from Korean Food Standards Codex (KFSC), Food Safety and Inspection Service (FSIS, USA), and the modified FSIS method using QuEChERS kit (FSIS-Q), respectively. Each method was compared for mean recoveries and repeatabilities. Since FSIS-Q showed higher repeatabilities (coefficient of variation, CV of 2.4%~10.9%) than those of FSIS method (CV of 4.6%~17.5%), recoveries from FSIS-Q were compared with those from KFSC method. FSIS-Q showed significantly higher recoveries of 83.1%~110.1% (P < 0.05) than those from KFSC method of 64.7%~107.4%. In addition, FSIS-Q showed a good linearity over the range of 2.5~200 ㎍/kg, and excellent sensitivities with limit of detection of 0.46~0.71 ㎍/kg and limit of quantification of 1.08~2.15 ㎍/kg. Although all the sample preparation methods turned out to be able to meet CODEX guideline for all the compounds, FSIS method and FSIS-Q validated in this study could be applied to screening and quantification for residues of febantel and its metabolites in rockfish muscle with efficient preparation procedures.

Emodin exerts protective effect against palmitic acid-induced endoplasmic reticulum stress in HepG2 cells

  • Thomas, Shalom Sara;Park, Sora;Cha, Youn-Soo;Kim, Kyung-Ah
    • Journal of Nutrition and Health
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    • 제52권2호
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    • pp.176-184
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    • 2019
  • Purpose: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. Methods: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as $IRE1{\alpha}$, $eIF2{\alpha}$ and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with $750{\mu}M$ palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. Results: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of $p-IRE1{\alpha}$, $p-eIF2{\alpha}$ and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. Conclusion: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.

부채마 에탄올 추출물의 아토피 피부염 억제 효과 (Suppressing Effects of Ethanol Extract from Dioscoreae Rhizoma on atope Dermatitis)

  • 도영복;송영순
    • 디지털융복합연구
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    • 제17권8호
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    • pp.257-264
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    • 2019
  • 본 연구는 부채마 70% 에탄올 추출물(DR)이 RBL-2H3 마스트 세포에서 항원에 의한 세포활성의 영향과 BALB/c 쥐에서 dinitrofluorobenzene에 의해 유도된 마스트 세포-매개 알레르기 접촉성피부염에 미치는 영향을 조사했다. DNP-HSA 항원과 Anti-DNP IgE 항체에 의해 활성 된 RBL-2H3 세포에서 에탄올 추출물은 급성 항원반응 표지인 ${\beta}$-hexosaminidase 분비와 히스타민 등을 억제하였고, 후기 항원반응 표지인 IL-4와 $TNF-{\alpha}$ 생성을 억압하였다. DNFB-유도 접촉성 알러지성 피부염 동물 모델에서 에탄올 추출물 처리는 귀 부기를 감소시키고 혈청 히스타민과 IL-4 분비를 억제시켰으며, DR 처리는 피부염 유발 부분에서 마스트 세포 유입을 효과적으로 방지하였다. 이러한 결과로, 에탄올 추출물은 아토피 피부염과 같은 마스트 세포-매개 알러지성 질병의 치료제로 사용할 수 있을 것이다.