• 센서학회지
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• 제23권3호
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• pp.185-191
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• 2014

The width of depletion region in a varactor diode can be modulated by varying a reverse bias voltage. Thus, the preferred characteristics of depletion capacitance can obtained by the change in the width of depletion region so that it can select only the desirable frequencies. In this paper, the TV tuner varactor diode fabricated by hyper-abrupt profile control technique is presented. This diode can be operated within 3.3 V of driving voltage with capability of UHF band tuning. To form the hyperabrupt profile, firstly, p+ high concentration shallow junction with $0.2{\mu}m$ of junction depth and $1E+20ions/cm^3$ of surface concentration was formed using $BF_2$ implantation source. Simulation results optimized important factors such as epitaxial thickness and dose quality, diffusion time of n+ layer. To form steep hyper-abrupt profile, Formed n+ profile implanted the $PH_3$ source at Si(100) n-type epitaxial layer that has resistivity of $1.4{\Omega}cm$ and thickness of $2.4{\mu}m$ using p+ high concentration Shallow junction. Aluminum containing to 1% of Si was used as a electrode metal. Area of electrode was $30,200{\mu}m^2$. The C-V and Q-V electric characteristics were investigated by using impedance Analyzer (HP4291B). By controlling of concentration profile by n+ dosage at p+ high concentration shallow junction, the device with maximum $L_F$ at -1.5 V and 21.5~3.47 pF at 0.3~3.3 V was fabricated. We got the appropriate device in driving voltage 3.3 V having hyper-abrupt junction that profile order (m factor) is about -3/2. The deviation of capacitance by hyper-abrupt junction with C0.3 V of initial capacitance is due to the deviation of thermal process, ion implantation and diffusion. The deviation of initial capacitance at 0.3 V can be reduced by control of thermal process tolerance using RTP on wafer.

• 미생물학회지
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• 제52권1호
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• pp.84-97
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• 2016

재래식 된장으로부터 분리된 유산균은 형태학적, 생화학적 특성과 당 발효능 및 16S rRNA 염기서열 분석을 통해 Enterococcus faecium SBP12, Pediococcus halophilus SBP20, Lactobacillus fermentum SBP33, Leuconostoc mesenteroides SBP37, Pediococcus pentosaceus SBP41, Lactobacillus brevis SBP49, Lactobacillus acidophilus SBP55 및 Enterococcus faecalis SBP58로 동정되었다. SBP20, SBP33, SBP49와 SBP55 균주는 인공 위액과 담즙액 내에서 6 log cycle 이상 생균수를 유지하였으나, SBP12와 SBP58은 낮은 pH 하에서 2시간만에 균수가 급격하게 감소되었다. 특히, SBP49와 SBP55는 HT-29 세포에 대한 부착능이 높고, 항생제에 대한 저항성이 크며, Bacillus cereus ATCC 11778과 Staphylococcus aureus ATCC 6538의 식중독균에 대한 항균활성을 나타내었으므로, 이 두 균주는 프로바이오틱 선발 기준에 적합한 것으로 추정된다. 게다가 SBP49와 SBP55를 이용하여 사워도우를 제조한 결과, 발효 직후 도우 내 pH, 산도 및 유산균수에는 유의한 차이가 없었으나, SBP49는 많은 양의 유산을 생산한 반면, SBP55는 과산화수소를 더 많이 생산하였다. SBP49와 SBP55 유산균은 유산과 과산화수소뿐만 아니라 박테리오신 등의 항균물질을 생산하므로 사워도우 내 존재하는 식중독균 저해에 효과적이었다.

• 한국자원식물학회지
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• 제18권1호
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• pp.15-21
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• 2005

염류내성 식물은 염류농도의 변화에 따라 세포내의 삼투압을 유지하기 위한 화합물을 합성하는 기작을 가지고 있는데 이런 화합물은 주로 proline, glycine, betaine, polyols, sugar등으로 체내에 축적함으로서 고농도의 염류에 견디는 것으로 알려져 있다. Betaine은 미생물에서 2단계 반응을 통해 choline에서 합성되는데, 첫단계는 choline dehydrogenase (CDH)에 의해서 촉매되고(Bet A gene), bet B 유전자의 산물인 betaine aldehyde dehydrogenase(BADH)에 의해 수행된다. 본 실험에서는 Bet A, Bet B 유전자를 아그로박테리움에 도입하여 새로운 conjugants 2 종을 획득하였으며 (Agrobacterium tumefaciens MP90/pBet A, Agrobacterium tumefaciens MP90/pBet B), 먼저 재조합된 binary vector가 식물에서 발현 및 형질 전환되는지 여부를 조사하기 위해서 이미 담배에 형질전환을 시켰으며, 형질전환된 담배에서는 ,고농도의 kanamycin배지에서 생장이 가능하였고, PCR에 의하여 NPT II, Bet A, Bet B gene를 조사한 결과 담배 유식물체 모두 band가 형성되어 형질전환체임을 확인할 수 있었다. 인삼에 Beth, BetB gene의 도입은 1M의 mannitol이 함유된 식물호르몬 무첨가 MS 배지에서 단일배 발생방법에 형질전환체를 획득하였으나, 형질전환체의 발생빈도$(12\%)$가 매우 낮았다.

• 자원환경지질
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• 제42권5호
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• pp.427-434
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• 2009

유류 및 중금속으로 오염된 토양에서 Pb 및 Cd에 내성을 갖는 미생물을 분리하여 미생물 내 중금속 흡착 특성을 조사하였다. 분리한 토착미생물의 Pb 및 Cd의 흡착특성과 흡착에 영향을 미치는 요인 중에 생장단계, 중금속 농도, 생물량, pH, 온도에 따른 영향을 비교하였다. 또한 흡착등온식을 적용하여 중금속의 흡착용량과 흡착강도를 알아보았다. 낮은 중금속 초기 농도와 높은 생물량에서 높은 중금속 제거 효율을 가지며 중금속 마다 다른 흡착 효율을 보여 주었다. 흡착 효율은 미생물 생장 말기, pH 5~9 조건에서 최적의 효율을 나타내었으나, 25~$35^{\circ}C$에서 온도 변화에 따른 영향은 미미하였다. 생물흡착 과정을 Langmuir 등온 흡착식에 적용하면, 이론적 최대 흡착량은 Pb와 Cd에 대해서 각각 62.11과 192.31 mg/g로 나타났고, $R^2$가 0.71과 0.98로 계산되었다. Cd는 세포 표면의 단일 층에 단분자 흡착에 의한 생물흡착이 진행되었으나, Pb는 미생물 대사 작용을 통한 세포 내로의 축적 작용과 미생물 내 음이온과의 반응에 의한 침전물 형성작용 둥을 통하여 생물흡착이 진행된 것으로 판단된다.

• Journal of Chest Surgery
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• 제47권3호
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• pp.233-239
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• 2014

Background: As hypertrophied myocardium predisposes the patient to decreased tolerance to ischemia and increased reperfusion injury, myocardial protection is of utmost importance in patients undergoing aortic valve replacement (AVR) for severe aortic valve stenosis (AS). Methods: Consecutive 314 patients (mean age, $62.5{\pm}10.8$ years; 143 females) with severe AS undergoing isolated AVR were included. Postoperative myocardial injury (PMI) was defined as 1) maximum postoperative creatinine kinase isoenzyme MB or troponin-I levels ${\geq}10$ times of reference, 2) postoperative low cardiac output syndrome or episodes of ventricular arrhythmia, or 3) left ventricular ejection fraction of less than 55% and decrease in left ventricle (LV) ejection fraction of more than 20% of the baseline value. Results: There were 90 patients (28.7%) who developed PMI. There were five cases of early death (1.6%), all of whom had PMI. On multivariable analysis, the use of histidine-tryptophan-ketoglutarate (HTK) solution instead of blood cardioplegia (odds ratio [OR], 3.06; 95% confidence interval [CI], 1.63 to 5.77; p=0.001), greater LV mass (OR, 1.04; 95% CI, 1.01 to 1.07; p=0.007), and increased cardiac ischemic time (OR, 1.13; 95% CI, 1.05 to 1.22; p<0.001) were independent predictors for PMI. Patients who had PMI showed significantly inferior long-term survival than those without PMI (p=0.049). Conclusion: PMI occurred in a considerable proportion of patients undergoing AVR for severe AS and was associated with poor long-term survival. HTK cardioplegia, higher LV mass, and longer cardiac ischemic duration were suggested as predictors of myocardial injury.

• 대한감각통합치료학회지
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• 제16권3호
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• pp.1-10
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• 2018

목적 : 본 연구는 작업치료전공 대학생의 성별을 구분하여 스마트폰 중독과 감각처리특성 차이를 알아보고, 감각처리특성과 스마트폰 중독 사이의 상관관계를 알아보고자 하였다. 연구방법 : 연구 참여자는 작업치료학을 전공하고 있는 169명의 대학생이었고, 연구기간은 2017년 11월부터 2018년 3월까지이었다. 연구방법은 설문조사로 일반적 특성, 스마트폰 중독척도, 성인/청소년 감각프로파일로 구성된 설문지를 온라인을 통해 실시하였다. 분석은 SPSS 22.0의 기술통계, 독립표본 t-test, 피어슨 상관분석으로 하였다. 결과 : 남학생 70명과 여학생 99명이 연구에 참여하였고 스마트폰의 사용하는 목적은 커뮤니케이션 이용에서 가장 응답이 높았고, 그 다음 순이 오락이었다. 남녀 사이의 스마트폰 중독의 차이는 스마트폰 중독 합계(p=.000)와 가상세계지향(p=.008), 금단(p=.000), 내성(p=.000)에서 보였다. 남학생에서는 스마트 폰 중독과 모든 감각처리 요소와 영역이 관련성이 있었다(r= .236 ~ .603). 여학생에서 스마트폰 중독합계와 감각처리요소의 맛/남새 처리(r= .290), 시각처리(r= .324), 촉각처리(r= .214), 사분면 중 저등록(r= .214), 감각 민감(r= .243), 감각 회피(r= .217)와 중독합계가 낮은 상관관계로 나타났다. 결론 : 대학생의 성별에 따라서 스마트폰 중독과 감각처리특성의 상관관계에 차이가 있었다. 스마트폰 중독과 관련 평가 및 중재시 감각처리특징을 고려해야 할 것이다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제21권2호
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• pp.111-117
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• 2018

Purpose: The prevalence of obesity has significantly increased among children and adolescents worldwide and is becoming an important health care problem in parallel with the increased prevalence of obesity pediatric non-alcoholic fatty liver disease. Betatrophin is a newly define hormone that is commonly secreted by liver and plays role in glucose tolerance. This study aimed to investigate the relationship between serum betatrophin levels and non-alcoholic fatty liver disease in obese children. Methods: The study included 40 obese children with a body mass index (BMI) above 95th centile, and 35 non-obese subjects with a BMI 3-85th centile, whose age and gender were similar to those of the patient group. For the evaluation of metabolic parameters fasting serum glucose, insulin, alanine aminotransferase, aspartate aminotransferase, lipid profile and serum betatrophin levels were measured. Total cholesterol: high-density lipoprotein cholesterol and low-density lipoprotein cholesterol: high-density lipoprotein cholesterol ratios were calculated as "atherogenic indices." Results: Serum betatrophin levels of the obese subjects were similar to that of non-obese subjects (p=0.90). Betatrophin levels were not correlated with the metabolic parameters. Conclusion: In the present study, levels of betatrophin are not different between obese and insulin resistant children and non-obese subjects, and they are not correlated with atherogenic indices. To elucidate the exact role of betatrophin in obesity, further studies are required to identify the betatrophin receptor and/or other possible cofactors.

• 천문학회보
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• 제39권2호
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• pp.103-103
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• 2014

Manufacturing of lens and mirror using Diamond Turning Machine (DTM) offers distinct advantages including short fabrication time and low cost as compared to grinding or polishing process. However, the DTM process can leave mid-frequency error in the optical surface which generates an undesirable diffraction effect and stray light. The mid-frequency error is expected to be eliminated by mechanical polishing after the DTM process, but polishing of soft surface of ductile aluminum is extremely difficult because the polishing process inevitably degrades the surface form accuracy. In order to increase its surface hardness, we performed electroless nickel plating on the surface of diamond-turned aluminum (Al-6061T6) off-axis mirrors, which was followed by the 6-hour-long baking process at $200^{\circ}C$ for improving its hardness. Then we polished the nickel plated off-axis mirrors to remove the mid-frequency error and measured polished mirror surfaces using the optical surface profilometer (NT 2000, Wyko Inc.). Finally, we ascertained that the mid-frequency error on the mirror surface was successfully removed. During the whole processes of nickel plating and polishing, we monitored the form accuracy using the ultra-high accurate 3-D profilometer (UA3P, Panasonic Corp.) to maintain it within the allowable tolerance range (< tens of nm). The polished off-axis mirror was optically tested using a visible laser source and a pinhole, and the airy pattern obtained from the polished mirror was compared with the unpolished case to check the influence of mid-frequency error on optical images.

• 한국인삼전략화협의회:학술대회논문집
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• 한국인삼전략화협의회 2003년도 제4차 한국인삼약초산업 전략화 세미나
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• pp.77-88
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• 2003

"Ginseng (Panax ginseng C.A. Meyer) has been a popular herbal remedy used in eastern Asian cultures for thousands of years, and a number of health claims are made for it. Modern therapeutic claims for ginseng refer to vitality, immune function, cancer, cardiovascular diseases, diabetes and sexual function. These claims are mostly based on uncontrolled or non-randomized studies. Among modern therapeutic claims, however, therapeutic effects for diabetes can reasonably be accepted. Following experiment was done recently in our lab: this study was designed to compare the antidiabetic activities between Ginseng Radix Alba (GRA), Ginseng Radix Rubra (GRR) and Panax Quinquefoli Radix (PQR) in multiple low dose (MLD) streptozotocin (STZ) (20mg/kg i.p injection for 5 days) induced diabetic rats. In the glucose tolerance test, 500mg/kg of each ginseng ethanol extract was admoinistered intraperitoneally 30min before glucose challenge. While GRA failed to lower blood glucose level, GRR and PQR both significantly prevented the hyperglycemia when compared with the control group. In the MLD STZ-induced diabetic rats, 300 mg/kg of each ginseng ethanol extract was administered intraperitoneally for 2 weeks. Plasma glucose and insulin levels were markedly improved in all treatment groups. While GRR showed the highest antidiabetic activity, and GRA and PQR revealed somewhat equipotent antidiabetic activities, but less than that in GRR-treated group as for as blood parameters and diabetic symptoms such as polydipsia are concerned. Blood glucose levels were closely associated with plasma insulin levels, and this result may suggest that ginseng ethanol extracts showed the activity to enhance insulin secretion as well as preventing destruction of pancreatic islet cells. To elucidate the relationship between antidiabetic activity and ginsenoside profiles, seven major ginsenoside were quantified by HPLC. We figured out the fact that protopanaxatriol (PPT) : proptopanaxadiol (PPD) ratio might play an important role in its hypoglycemia effects."

• 한국식품위생안전성학회지
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• 제11권4호
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• pp.315-321
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• 1996

Various antimicrobial drug screen tests have been used in order to ensure food safety. However, the conventional screen tests, the Swab Test on Premises(STOP, USA), the Calf Antibiotic and Sulfa Test(CAST, USA) and the European Economic Community 4-plate Test(FPT, EU) are not sufficiently rapid or sensitive enough to detect low levels of sulfa drugs in meat. We developed a new screen test kit for the determination of the antimicrobial residues in meat called the Bacillus megaterium Disk Assay(BmDA). A comparison of BmDA with the older screen tests showed BmDA was as good as the older ones with several advantages. The new test kit is faster-it can be read in 4∼6 hours instead of 16∼18 hours. Moreover, BmDA can discriminate sulfa drugs from other antimicrobial drugs because p-aminobenzoic acid countacts the inhibiting action of sulfa drugs. Minimum detectable levels of sulfa drugs were significantly improved at the lever of 0.025*0.1 pp, compared with the level of 1.0 ppm in FPT. A comparison of BmDA with the older screen tests in HPLC confirmed meat samples exceeded the Korean tolerance value of 0.1 ppm showed BmDA was the most sensitive in the microbiological screen tests. As the microbiological screen tests have already known, a person familiar with simple laboratory techniques should have no difficulty in using it to detect antimicrobial residues in meat. This would be a simple, economic method of antimicrobial residues detection which might be succesfully used by many laboratories.