• Korean Chemical Engineering Research
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• 제47권5호
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• pp.593-598
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• 2009

정상경유에 등유 및 부생연료유를 인위적으로 혼합한 후, SPE 전처리 과정과 HPLC 분석을 통해 석유제품 내에 함유되어 있는 식별제의 정성 정량분석방법에 관해 연구하였다. SPE 전처리 과정에서 시료주입 후 15분에 분취된 시료에서 가장 높은 농도의 식별제가 분석되었다. 경유제품에 1 mg/L의 식별제를 혼입시킨 후, 전처리를 거쳐 HPLC로 분석한 결과 9.8분의 머무름시간에서 $1626.92mV{\cdot}sec$ 의 감도로 식별제가 분석되었으며, 또한 기존의 UV-Spectroscopy법으로 분석이 힘들었던 산성조건의 석유제품에서 식별제 분석이 가능하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제1권2호
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• pp.115-134
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• 1988

In view of the wide range that occurs in the nutritive value of cereal straw, the factors that may contribute are discussed under the heading of : (a) genetic factors; (b) environment factors affecting the pattern of plant growth; and (c) management factors associated with grain harvest and threshing and straw storage. The possible ways of improving the nutritive value of cereal straw without pretreatment may be achieved by selecting and breeding better cereal straw, by controlling environmental factors, by controlling management practices and by appropriate supplementation strategies to alleviate deficiencies of essential nutrients. Thus improvement in the nutritive value of cereal straw would be attained without pretreatment.

• Korean Chemical Engineering Research
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• 제61권3호
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• pp.412-418
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• 2023

The surge in the oil prices, increasing global population, climate change, and waste management problems are the major issues which have led to the development of biofuels from lignocellulosic wastes. Cellulosic or second generation (2G) bioethanol is produced from lignocellulosic biomass via pretreatment, hydrolysis, and fermentation. Pretreatment of lignocellulose is of considerable interest due to its influence on the technical, economic and environmental sustainability of cellulosic ethanol production. In this study, furniture waste sawdust was subjected to alkaline peroxide (H₂O₂) for the production of reducing sugars. Sawdust was pretreated at different concentrations from 1-3% H₂O₂ (v/v) loadings at a pH of 11.5 for a residence time of 15-240 min at 50, 75 and 90 ℃. Optimum pretreatment conditions, such as time of reaction, operating temperature, and concentration of H₂O₂, were varied and evaluated on the basis of the amount of total reducing sugars produced. It was found that the changes in the amount of lignin directly affected the yield of reducing sugars. A maximum of 50% reduction in the lignin composition was obtained, which yielded a maximum of 75.3% total reducing sugars yield and 3.76 g/L of glucose. At optimum pretreatment conditions of 2% H₂O₂ loading at 75 ℃ for 150 min, 3.46 g/L glucose concentration with a 69.26% total reducing sugars yield was obtained after 48 hr. of the hydrolysis process. Pretreatment resulted in lowering of crystallinity and distortion of the sawdust after the pretreatment, which was further confirmed by XRD and SEM results.

• The Korean Journal of Pain
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• 제25권3호
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• pp.155-160
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• 2012

Background: We have developed an intradiscal pulsed radiofrequency (Disc PRF) technique, using Diskit $II^{(R)}$ needles (NeuroTherm, Wilmington, MA, USA), as a minimally invasive treatment option for chronic discogenic low back pain (LBP). The purpose of this study was to compare the representative outcomes of Disc PRF and Intradiscal Electrothermal Therapy (IDET) in terms of pain relief and reduction of disability. Methods: Thirty-one patients with chronic discogenic LBP who underwent either Disc PRF (n = 15) or IDET (n = 16) were enrolled in the study. A Diskit $II^{(R)}$ needle (15-cm length, 20-gauge needle with a 20-mm active tip) was placed centrally in the disc. PRF was applied for 15 min at a setting of $5{\times}50$ ms/s and 60 V. The pain intensity score on a 0-10 numeric rating scale (NRS) and the Roland-Morris Disability Questionnaire (RMDQ) were assessed pretreatment and at 1, 3, and 6 months post-treatment. Results: The mean NRS was significantly improved from $7.2{\pm}0.6$ pretreatment to$2.5{\pm}0.9$ in the Disc PRF group, and from $7.5{\pm}1.0$ to $1.7{\pm}1.5$ in the IDET group, at the 6-month follow-up. The mean RMDQ also showed significant improvement in both the Disc PRF group and the IDET group at the 6-month follow-up. There were no significant differences in the pretreatment NRS and RMDQ scores between the groups. Conclusions: Disc PRF appears to be an alternative to IDET as a safe, minimally invasive treatment option for patients with chronic discogenic LBP.

• 한국물환경학회지
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• 제36권1호
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• pp.55-68
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• 2020

Because of the intensified environmental problems such as climate change and resource depletion, sewage treatment technology focused on energy management has recently attracted attention. The conversion of primary sludge from the primary sedimentation tank and excessive sludge from the secondary sedimentation tank into biogas is the key to energy-positive sewage treatment. In particular, the primary sedimentation tanks recover enriched biodegradable organic matter and anaerobic digestion process produces methane from the organic wastes for energy production. Such technologies for minimizing oxygen demand are leading the innovation regarding sewage treatment plants. However, sewage treatment facilities in Korea lack core technology and operational know-how. Actually, the energy potential of sewage is higher than sewage treatment energy consumption in the sewage treatment, but current processes are not adequately efficient in energy recovery. To improve this, it is possible to apply chemically enhanced primary treatment (CEPT), high-rate activated sludge (HRAS), and anaerobic membrane bioreactor (AnMBR) to the primary sedimentation tank. To maximize the methane production of sewage treatment plants, organic wastes such as food waste and livestock manure can be digested. Additionally, mechanical pretreatment, thermal hydrolysis, and chemical pretreatment would enhance the methane conversion of organic waste. Power generation systems based on internal combustion engines are susceptible to heat source losses, requiring breakthrough energy conversion systems such as fuel cells. To realize the energy positive sewage treatment plant, primary organic matter recovery from sewage, biogas pretreatment, and co-digestion should be optimized in the energy management system based on the knowledge-based operation.

• 한국식생활문화학회지
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• 제37권2호
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• pp.153-161
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• 2022

This study was undertaken to examine the quality characteristics of nonblanched carrots (CON) and carrots blanched in distilled water, 2% NaCl water and 2% citric acid at 100℃ for 3 minutes. This moisture contents of CON was the highest at 85.91%, whereas NT had the lowest moisture at 83.92% (p<0.01). Compared to CON values the L values of pretreatment groups were decreased whereas the b values were increased (p<0.001) A comparison of true retention (TR), revealed that NT had the highest TPC TR 101.04% and TFC TR 91.59% (p<0.001). β-Carotene contents were determined to be higher in NT (1.98 mg/100 g) and CT (1.94 mg/100 g) than in other groups, with highest levels obtained in NT (106.64%) (p<0.001). Examination of the DPPH and ABTS+ radical scavenging activities revealed that the NT group had maximum scavenging activity. The total bacterial count was determined to be 3.37 log CFU/g in the CON, whereas no microorganisms were observed in all the pretreatment groups. Our study indicates that blanching in 2% NaCl water is the most desirable in order to increase the biochemical content and nutrient preservation rate of carrots, and to inhibit the growth of microorganisms.

• Journal of Acupuncture Research
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• 제25권4호
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• pp.117-125
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• 2008

Objectives : Analyze according to types of event causing the adverse outcome due to acupotomy, and discuss problems and safety reqirements to using this therapy in Korea. Methods : Based upon the indication, contraindication, treatment procedures, clinical obsevations, acupotomy-related adverse outcome case reports, the factors of damaging event were classified. Results : The main factors of adverse outcome by acupotomy were anatomical ignorance, contamination of device or hospital staff, failure to notice preexisting disease(cardiovascular disease, hypertension, renal failure, hemophilia, chronic Liver Disease, etc.), unskilled treatment procedures(massive bleeding) and techniques(nerve injury, hepatic and splenic injury, Pneumothorax). Conclusions : It is mandatory to prepare adequate sterilie aseptic technique. The clinician should ensure understand genernal health state of patient and anatomical direction.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.77-77
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• 2003

Sepsis remains common surgical problems with high morbidity and mortality despite improvement in the management for septic patient. Although hepatocellular dysfunction occurs during sepsis, the mechanism responsible for this remains unclear. In sepsis, a state of severe oxidative stress is encountered, with host endogenous antioxidant defenses overcome. Therefore, the aim of this study was to determine the effect of a-tocopherol (AT) vasoregulatory gene expression during polymicrobial sepsis. Rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP). AT (15 mg/kg) was intraperitonealy injected for 3 days prior to CLP. Blood samples were taken 24 h after CLP for measurement of the extent of hepatocellular damage. Liver samples were taken for RT-PCR analysis of mRNA for genes of interest: endothelin-l (ET-l), its receptors $ET_{A}$ and $ET_{B}$, nitric oxide synthases (iNOS and eNOS), cyclooxygenase-2 (COX -2), heme oxygenase-l (HO-l), and tumor necrosis factor-$\alpha$ (TNF-$\alpha$). The activities of serum alanine aminotransferase and lipid peroxidation level were significantly increased; an increase which was prevented by AT pretreatment. CLP significantly increased the mRNA levels of ET-1 and $ET_{B}$; an increase that was prevented by AT pretreatment. However, the level of $ET_{A}$ mRNA significantly decreased after CLP; a decrease that was not prevented by AT pretreatment. There were significant increases in the mRNA expression of iNOS, HO-l and COX -2 in CLP groups. This increase was prevented by AT pretreatment. The expression of eNOS and TNF-$\alpha$ mRNA significantly increased in CLP, which was not prevented by AT pretreatment. Our findings suggest that there was an imbalanced vasoregulatory gene expression in sepsis, and AT ameliorates this change through its free radical scavenging activity.

• 한국식품저장유통학회지
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• 제30권6호
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• pp.969-982
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• 2023

This study evaluated the impact of blanching pak choi stems and leaves in various solutions (distilled water, 2% NaCl, and 2% citric acid) at 100℃ on their quality characteristics. The highest stem heating loss was observed in the sodium chloride solution (S-NB) at 15.10% (p<0.001), and the highest leaf heating loss was in L-NB at 11.44% (p<0.001). No significant variation was found in the moisture content of both stems and leaves. Relative to the control, the L value (lightness) of the stem decreased while the b value (yellowness) increased (p<0.05). In the leaves, the a value (redness/greenness) and b value increased in L-CB, whereas they decreased in other groups (p<0.05). S-NB exhibited the highest true retention (TR) of total polyphenol content (TPC) in stems (p<0.01) and the highest TR of total flavonoid content (TFC) as well (p<0.001). For leaves, the highest TR of TPC and TFC was in L-WB (p<0.001). In terms of antioxidant activity, S-NB in stems and L-WB in leaves showed the highest scavenging activity measured by DPPH and ABTS⁺ assays (p<0.001). Microorganisms were absent in all pretreatment groups but present in the control. The results suggest that blanching pak choi stems in 2% NaCl solution and leaves in water optimally preserves biologically active compounds and nutrients.

• 대한약침학회지
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• 제25권4호
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• pp.369-381
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• 2022

Objectives: Hyperlipidemia (HL) is a major cause of ischemic heart diseases. The size-limiting effect of ischemic preconditioning (IPC), a cardioprotective phenomenon, is reduced in HL, possibly because of the opening of the mitochondrial permeability transition pore (MPTP). The objective of this study is to see what effect pretreatment with Inula racemose Hook root extract (IrA) had on IPC-mediated cardioprotection on HL Wistar rat hearts. An isolated rat heart was mounted on the Langendorff heart array, and then ischemia reperfusion (I/R) and IPC cycles were performed. Atractyloside (Atr) is an MPTP opener. Methods: The animals were divided into ten groups, each consisting of six rats (n = 6), to investigate the modulation of I. racemosa Hook extract on cardioprotection by IPC in HL hearts: Sham control, I/R Control, IPC control, I/R + HL, I/R + IrA + HL, IPC + HL, IPC + NS + HL, IPC + IrA+ HL, IPC + Atr + oxidative stress, mitochondrial function, integrity, and hemodynamic parameters are evaluated for each group. Results: The present experimental data show that pretreatment with IrA reduced the LDH, CK-MB, size of myocardial infarction, content of cardiac collagen, and ventricular fibrillation in all groups of HL rat hearts. This pretreatment also reduced the oxidative stress and mitochondrial dysfunction. Inhibition of MPTP opening by Atr diminished the effect of IrA on IPC-mediated cardioprotection in HL rats. Conclusion: The study findings indicate that pretreatment with IrA e restores IPC-mediated cardioprotection in HL rats by inhibiting the MPTP opening.