• Title/Summary/Keyword: Differential Screening

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An Evaluation of Thermal Stability of Raw Materials in the Vinyl Acetate Polymerization Process (비닐아세테이트 중합공정에서 원료물질의 열적 안정성 평가)

  • Lee, Keun-Won;Han, In-Soo;Lee, Jung-Suk
    • Journal of the Korean Society of Safety
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    • v.25 no.3
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    • pp.61-65
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    • 2010
  • Most of the chemical reactions performed in the chemical industry are exothermic, meaning that thermal energy is released during the reaction. It is also important to understand the thermal hazards such as thermal stabilities and runaway reactions, which are governed by thermodynamics and reaction kinetics of the mixed materials. The paper was described the evaluation of thermal behavior caused by an exothermic batch process in manufacture of the vinyl acetate resin. The aim of the study was to evaluate the thermal stabilities of raw materials with operating conditions such as a reaction inhibitor, heating rate, reaction atmosphere and the mount of methanol charged in the vinyl acetate polymerization process. The experiments were performed in the differential scanning calorimeter(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). It was suggested that we should provide the thermal characteristics for raw materials to present safe precautions with operating conditions in the vinyl acetate polymerization process.

Screening of Differentially Expressed Genes in Diesel Oil-exposed Marine Fish Using DD-PCR

  • Woo, Seon-Ock;Yum, Seung-Shic;Yim, Un-Hyuk;Lee, Yaek-Kyun
    • Molecular & Cellular Toxicology
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    • v.2 no.4
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    • pp.251-256
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    • 2006
  • The exploration of genes which expressions are changed by exposure to ecotoxicants or pollutants can provide the important information about the reaction mechanisms in the body as well as adaptation to exterior stimulus or environmental changes. Also they can be developed as biomarkers for the detection of environmental pollution. Differential display polymerase chain reaction (DD-PCR) technique has been usefully used to hunt the clones which expressions are up-regulated or down-regulated by exterior changes and this study aimed to search for those clones in diesel oil-exposed rockfish (Sebastes schlegeli) using DD-PCR. The RNA isolated from liver of 20 ppb diesel oil-exposed rockfish was used for screening of the differentially displayed genes and total 44 differentially expressed genes (DEG) are detected then their nucleotide sequences were analyzed. The present data provided the general information about the effect of diesel oil contamination on marine organism and further more the primary step in development of new biomarkers for marine environmental pollution or ecotoxicological stresses.

Construction and Differential Screening of a cDNA Library Specific to Osmotic Stress of Haloxylon ammodendron Seedlings

  • Jiang, Xiao-Cheng;Guo, Xin-Hong;Pan, Xiao-Ling;Song, Song-Quan
    • BMB Reports
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    • v.37 no.5
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    • pp.527-532
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    • 2004
  • A subtracted cDNA library specific to osmotic stress of Haloxylon ammodendron (Mey.) Bge seedlings was constructed by suppression subtractive hybridization (SSH) and T/A cloning. SSH was performed between two groups of H. ammodendron seedlings, one was cultivated in Hoagland (H) solution as a driver and the other group was treated with osmotic stress of the Hoagland solution by the addition of 400 mM mannitol (M), as a tester. The library consisted of about 400 recombinant clones, with the average size being of 500 bp, ranging from 300 bp to 1500 bp. Using a PCR-select differential screening kit, 100 recombinant clones were randomly chosen from the subtracted cDNA library and hybridized with forward,reverse subtracted and unsubtracted probes for two rounds. As a result, 21 positive clones specific to osmotic stress were obtained and some of them were verified by Northern blot analysis. The sequencing analysis of 6 positive clones and the following homology comparison to GenBank [blastx] non-redundant databases characterized that two sequences obtained in this experiment may contribute to novel drought-related genes.

An Evaluation of Thermal Stability on Esterification Process in Manufacture of Concrete Mixture Agents (시멘트 혼화제 제조시 에스테르화공정의 열 안정성 평가)

  • Lee, Keun-Won;Lee, Jung-Suk;Choi, Yi-Rae;Han, In-Soo
    • Journal of the Korean Society of Safety
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    • v.24 no.4
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    • pp.40-46
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    • 2009
  • The early identification of thermal hazards associated with a process such as the heats of reaction, exothermic decompositions, and the understanding of thermodynamics before any large scale operations are undertaken. The evaluation of reaction factors and thermal behavior on esterification process in manufacture of concrete mixture agents are described in the present paper. The experiments were performed in the differential scanning calorimetry(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). The aim of the study was to evaluate the thermal stability of single material and mixture in esterification process. We provided the thermal data of chemical materials to present safe operating conditions through this study.

Isolation and Characterization of Inducible Genes from Bombyx mori Injected with E. coli by Differential Screening (누에에의 차별화 선별을 통한 면역 관련 유도 유전자의 분리와 특성)

  • 김상현;제연호
    • Journal of Sericultural and Entomological Science
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    • v.38 no.1
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    • pp.19-24
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    • 1996
  • To investigate the genes which is related to immune reaction of Bombyx mori, differential screening was carried out using naive and induced B. mori mRNA probe. To begin with, we constructed the cDNA library with mRNA isolated from fifth instar larvae injected with E. coli(4 X 106 cells/larva) using Uni ZAP XR vector kit. Thirty-two inducible cDNAs showing higher intensity on the induced mRNA probing membranes were selected. Partial nucleotide sequences of 29 clones were determined and their expessed sequence tags (ESTs) were produced. Nineteen ESTs in 29 ESTs were matched in GenBank database and the rest of them were found to be unknown. These unmatched ESTs were presumed to be novel genes. The nineteen ESTs contained variable genes related to biological process in Bombyx mori and four classes immune genes. Four clones, BmInc 6, 8, 18 and 27 were similar to two antibacterial peptide genes, hemolin gene and transferrin gene, respectively.

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Screening for MiRNAs Related to Laryngeal Squamous Carcinoma Stem Cell Radiation

  • Huang, Chang-Xin;Zhu, Ying;Duan, Guang-Liang;Yao, Ji-Fen;Li, Zhao-Yang;Li, Da;Wang, Qing-Qing
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4533-4537
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    • 2013
  • Objective: To use microarray chip technology for screening of stem cell radiation related miRNAs in laryngeal squamous cell carcinoma; study and explore the relationship of miRNAs with radiosensitivity of laryngeal squamous cells. Method: After conventional culture and amplification of the laryngeal squamous carcinoma cell line Hep-2, CD 133+ cells were screened out with combination of isolated culture of stem cell microspheres and FACS for preparation of laryngeal cancer stem cells. After radiation treatment, miRNAs of laryngeal squamous carcinoma stem cells before and after radiation were enriched and purified. After microarray hybridization with mammalian miRNA and scanning of fluorescence signal, the miRNAs of laryngeal squamous carcinoma stem cells before and after radiation was subject to differential screening and clustering analysis. Real-time quantitative RT-PCR was used to verify part of the differentially expressed miRNAs. Results: 70 miRNAs related to laryngeal cancer stem cell radiation with 2-fold difference in expression were screened out, in which 62 were down-regulated and 8 were up-regulated. Fluorescent quantitative RT-PCR results were consistent with miRNAs chip results. Conclusion: Some miRNAs may be involved in self-regulation with laryngeal squamous carcinoma stem cell radiation.

Identification of Fruit-specific cDNAs in a Ripened Inodorus Melon Using Differential Screening and the Characterization of on Abscisic Acid Responsive Gene Homologue

  • Hong, Se-Ho;Kim, In-Jung;Chung, Won-Il
    • Journal of Plant Biotechnology
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    • v.4 no.1
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    • pp.7-15
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    • 2002
  • Eight cDNAs corresponding to fruit-specific genes were isolated from ripened melon through differential screening. Sequence comparison indicated that six of these cDNAs encoded proteins were previously characterized into aminocyclopropane-1-carboxylate (ACC) oxidase, abscisic acid, stress and ripening inducible (ASR) gene, RINC-H2 zinc finger protein, pyruvate decarboxylase, or polyubiquitin. RFS2 and RFS5 were the same clone encoding polyubiquitin. The other cDNAs showed no significant homology with known protein sequences. The ASR homologue (Asr1) gene was further characterized on the cDNA and genomic structure. The deduced amino acid sequence had similar characteristics to other plant ASR. The Asr1 genomic DNA consisted of 2 exons and 1 intron, which is similar to the structure of other plants ASR genes. The promoter region of the Asr1 gene contained several putative functional cis-elements such as an abscisic acid responsive element (ABRE), an ethylene responsive element (ERE), a C-box or DPBf-1 and 2, Myb binding sites, a low temperature responsive element (LTRE) and a metal responsive element (MRE). The findings imply that these elements may play important roles in the response to plant hormones and environmental stresses in the process of fruit development. The results of this study suggest that the expressions of fruit specific and ripening-related cDNAs are closely associated with the stress response.

Abnormality on Liver Function Test

  • Kang, Ki-Soo
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.16 no.4
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    • pp.225-232
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    • 2013
  • Children with abnormal liver function can often be seen in outpatient clinics or inpatients wards. Most of them have respiratory disease, or gastroenteritis by virus infection, accompanying fever. Occasionally, hepatitis by the viruses causing systemic infection may occur, and screening tests are required. In patients with jaundice, the tests for differential diagnosis and appropriate treatment are important. In the case of a child with hepatitis B virus infection vertically from a hepatitis B surface antigen positive mother, the importance of the recognition of immune clearance can't be overstressed, for the decision of time to begin treatment. Early diagnosis changes the fate of a child with Wilson disease. So, screening test for the disease should not be omitted. Non-alcoholic fatty liver disease, which is mainly discovered in obese children, is a new strong candidate triggering abnormal liver function. Muscular dystrophy is a representative disease mimicking liver dysfunction. Although muscular dystrophy is a progressive disorder, and early diagnosis can't change the fate of patients, it will be better to avoid parent's blame for delayed diagnosis.

Performance Analysis of Intake Screens in Power Plants on Mass Impingement of Marine Organisms (발전소 취수구에 대량으로 유입하는 해양생물에 대한 스크린 설비의 성능분석)

  • Lee, Jae-Hac;Choi, Hyun-Woo;Chae, Jin-Ho;Kim, Dong-Sung;Lee, Seung-Baek
    • Ocean and Polar Research
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    • v.28 no.4
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    • pp.385-393
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    • 2006
  • Screening performance of the existing intake screens (drum and travelling screen) on mass impingement of marine animals, a euphausiid, Euphausia pacifica and a scyphozoan medusae, Aurelia aurita that have often clogged intake screens of the Uljin Nuclear Power Plant, was tested. The maximum tolerable densities of marine animals in the inflowing seawater upon the screen were estimated with two different approaches. First the maximum density of jellyfish was calculated from (1) passing amount of seawater per unit time through the screens and (2) the covered area of animals on the screens clogged. The maximum density of krill tolerable in the drum screen was cited from a simulated record of Uljin NPP, then those in the travelling screens were also calculated using the data of drum screen and ratio of seawater amount passing through the screens under the condition of 0.5m water column (W.C.) of the differential pressure (AP) produced by screens, an established permissible limit of ${\Delta}P$. Secondly, the screening performances were also tested by hydrodynamic measurements with various screen models in a circulating water channel equipped with a speed-controlling pump and a differential pressure gauge. From the first approach, the maximum tolerable densities of drum and travelling screen were calculated as 2.0 and $1.5ind/m^3$ for the Jellyfish and 900 and $680ind./m^3$ for the euphausiid, respectively. These densities estimated from the second approach were 2.1 and $0.8ind/m^3$ for the jellyfish and 1059 and $504ind/m^3$ for the euphausiid, respectively. These estimates were compared with the data from historic clogging events to evaluate the practical performance of these intake screens. The comparisons suggest a newly improved intake-screen of which performance should be at least seven times (approximately) better than the existing ones ior the krill and 3.2 times for the jellyfish, respectively, for preventing mass impingement, and for maintaining the condition of the differential pressure between the screens below 0.3 m W.C.

Compatibility Study Using Differential Scanning Calorimetry (시차주사열량분석을 이용한 배합성 연구)

  • Sohn, Young-Taek;Lee, Aea-Kyoung
    • Journal of Pharmaceutical Investigation
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    • v.29 no.2
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    • pp.117-126
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    • 1999
  • Differential scanning calorimetry(DSC) was used as a screening technique for assessing the compatibility of some drugs with excipients. On the basis of DSC results, interaction of ibuprofen with PVP K40 was found and eutectic formations with PEG 6000 or magnesium stearate were demonstrated. Fenoprofen Ca was found to interact with PEG 6000. Naproxen showed interactions with PEG 6000, PVP K40, PVPP and Mg stearate. Interactions of tiaprofenic acid with PVP K40 or PVPP were found and eutectic formations with PEG 6000 or Mg stearate were observed. Bisoprolol hemifumarate, metoprolol tartrate and penbutolol sulfate were found to interact with lactose.

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