Fabrication of CrN Thin-film Type Strain-guges for Metal Pressure Sernsors

Chung, Gwiy-Sang,Nam, Hyo-Duk 東西大學校 2000 동서논문집 Vol.6 No.-

The physical, electrical and piezoresitive characteristics of CrN(chromiun nitride) than-films on silicon substrates have been investigated for use as strain gauges. The thin-film depositions have been carried out by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(5 ∼25 %)N2) . The deposited CrN thin-films with thickness of 3500Å and annealing conditions(300℃, 48 hr) In Ar-10 % N2 deposition atmosphere have been selected as the ideal piezoresistive material for the strain gauges. Under optimum conditions, the CrN thin-films for the strain gauges is obtained a high electrical resistivity, ρ = 1147.65 μΩcm, a low temperature coefficient of resistance. TCR = -186 ppm/℃ and a high temporal stability with a good longitudinal gauge factor. GF = 11.17.

Development of Host - Temperature Controllable Vector System in Streptomyces

Chung,Dong Hyo,Shim,Sang Kook,Tatsuji,Seki 中央大學校 遺傳工學硏究所 1989 遺傳工學硏究論集 Vol.2 No.1

Streptomyces에서 온도에 의하여 유전자 발현이 조절되는 시스템을 개발하기 위하여 Streptomyces-E.coli에서 발효되는 온도조절형 발현 shuttle vector를 작제하였다. 작제된 plasmid에 존재하는 lacZ로 encoded된 β-galactosidase와 그 mRNA의 생산이 온도에 의하여 엄밀히 조절되었다. Stirred fermentor와 PHE type fementor에 의한 배양액의 순환발효에 있어서도 β-galactosidase의 생산이 적절히 조절되었다. 이러한 결과로 부터 작제된 온도조절형 발현 벡터를 이용하면 limiting enzyme의 양을 온도에 의하여 조절할 수 있으므로 Streptomyces로 부터 중간 대사산물을 생산하고져 할 때 이용할 수 있음을 알 수 있었다. To develop a gene expression system which could be regulated by temperature manipulation in Streptomyces, We constructed bifunctional Streptomyces-E. coli temperature-controllable shuttle vectors harbouring lacZgene of which expression was directed by promoter P? and P? and was controlled by cI? repressor. The synthesis of β-galactosidase as well as its specific mRNA was strictly controlled by temperature in Streptomyces. Repetitive switch on and off of the gene expression were also perfomed successfully. By recycling the culture broth between a conventional stirred fermentor and a plate heat exchange type fermentor, the amount of β-galactosidase was controlled at a desired level.

Purification of Xylanase from Escherichia coli Carrying pAX113 and its Comparison with Two Types of Xylanases from Thermophilic Alkalophilic Bacillus K-17

SUNG, NACK KIE,SHIM, KI HWAN,CHUNG, DUCK HWA,CHUN, HYO GON,HUR, SUNG HO 경상대학교 유전공학연구소 1986 遺傳工學硏究所報 Vol.5 No.-

The extracellular xylanase produced by E. coli HB101 carrying pAX113, which contains the xylanase I gene of thermophilic alkalophilic Bacillus K-17, was purified by ammonium sulfate precipitation, DEAE-Sephadex A-50 column chromatography, CM-Sepadex C-50 column chromatograhy and Sephadex G-100 gel filtration. The purified enzyme had a molecular weight of 23,000. The pH and temperature optima for its activities were 6.5 and 65℃, respectively. The enzyme retained full activity after incubation at 60℃ for 1hr or at pH 5-9 for 24 hr. The Km value of the enzyme was 4.65 mg-xylan/ml. These enzymatic properties of the xylanase were almost the same as those of xylanase I. Furthermore, we could purify a larger amount of xylanase from E. coli than from thermophilic alkalophilic BacillusK-17.

Feasibility of the Mucosa-Tracking Technique in Precut Papillotomy with the Iso-Tome as an Alternative to the Needle-Knife Technique

( Sang Heum Park ),( Do Hyun Park ),( Tae Hoon Lee ),( Ho Sung Lee ),( Yong Sub Lee ),( Sae Hwan Lee ),( Chang Kyun Lee ),( Suck Ho Lee ),( Il Kwun Chung ),( Hong Soo Kim ),( Hyo Jin Lee ),( Sun Joo K 대한소화기기능성질환·운동학회 2010 Gut and Liver Vol.4 No.1

Background/Aims: The aim of this study was to evaluate whether the mucosa-tracking technique is effective for improving precutting-related pancreatitis and the sustained failure of bile duct cannulation in precut papillotomy (PP) with the Iso-Tome (MTW Endoskopie). Methods: From September 2004 to June 2006, PP was performed with the Iso-Tome if biliary cannulation failed by conventional methods for approximately 5 minutes. The pink intrapapillary mucosa (PIPM) exposed by PP was tracked and classified into four groups: fully exposed and oriented to the direction of the bile duct (group A) or the pancreatic duct (group B), partially exposed (group C), or unexposed (group D). The success rate of bile duct cannulation (SRBC), the procedure time required for successful bile duct cannulation (PTBC), and the complications in the first session were compared between the mucosa-exposed groups (MEGs; group A, B, and C) and the mucosa-unexposed group (MUEG; group D). Results: A total of 59 patients (25 females, 34 males) with a mean age of 65.2 years were enrolled. The MEGs and MUEG comprised 52 (88.1%) and 7 (11.9%) patients, respectively. SRBC in the first session was 86.4% (51/59) in total and 92.3% (48/52) in the MEGs, compared to only 42.9% (3/7) in the MUEG (p=0.005). The mean PTBC in the MEGs and MUEG was 8.7 minutes and 16.3 minutes, respectively (p=0.23). Complications occurred in 6.8% of the patients (4/59; all pancreatitis); there were no differences between the MEGs (5.8%, 3/52) and MUEG (14.3%, 1/7; p=0.41). All four patients with pancreatitis were managed medically. Conclusions: The mucosa-tracking technique in PP with the Iso-Tome is a feasible and useful method of enhancing SRBC. PIPM is an important endoscopic landmark for successful PP. (Gut Liver 2010;4:76-83)

Subcloning and Sequencing of β-Xylosidase Gene of Alkalophilic Bacillus sp. K17

SUNG, NACK KIE,SHIM, KI HWAN,CHUN, HYO GON,CHUNG, CHUNG HEE,CHUNG, YOUNG CHUL,KO, HAK RYONG 경상대학교 유전공학연구소 1988 遺傳工學硏究所報 Vol.7 No.-

The 5.0kb insert of pAX278, which was previously cloned, was reduced by various deletion and thus I. 4kb EcoRI-XbaI fragment was recloned into pUC19(pAK208). To increase β-xylosidase activity, the I. 4kb insert in pAK208 was recloned into expression vector, pKK223-3 (tac-promoter), and β-xylosidase activity in cell carring this plasmid (pKHR212) was increased was 3.5 times than that in pAX278. The complete nucleotide sequence of thermophilic alkalopilic Bacillus sp. K17 and its flanking regions were established. A 1263-bp open reading frame for β-xylosidase was observed. The molecular weight(50, 521 dalton) deduced from for β-xylosidase gene, was agreed with the result obtained by SDS-polyacry-lamide gel electrophoresis of the purified enzyme. The Shine-Dalgarno sequence was found-8 bp upstream of the initiation codon ATG. The 1-10 regions for promotor sequence of β-xylosidase gene were similar to the consensus sequence for B. subtilis RNA polymerase, and the-35 regions were different from all the known promotor for B. subtilis RNA polymerase.

Elemental Sulfur as a Reactive Medium for Gold Nanoparticles and Nanocomposite Materials

Chung, Woo Jin,Simmonds, Adam G.,Griebel, Jared J.,Kim, Eui Tae,Suh, Hyo Seon,Shim, In‐,Bo,Glass, Richard S.,Loy, Douglas A.,Theato, Patrick,Sung, Yung‐,Eun,Char, Kookheon,Pyun, Jeffrey WILEY‐VCH Verlag 2011 Angewandte Chemie Vol.123 No.48

<P><B>Schwefelgelb:</B> Elementarer Schwefel wird als unkonventionelles Medium für die Synthese und Stabilisierung von kolloidalem Gold genutzt. In diesem System erfüllt Schwefel viele Funktionen, wie die Sulfurierung von PPh<SUB>3</SUB> und die Solubilisierung und Reduktion von Au<SUP>I</SUP>‐Vorstufen zu Au‐Nanopartikeln (NPs; siehe Bild). Die Vulkanisation von Au‐haltigen Schwefeldispersionen erfordert vernetzte Nanokomposite, die mit TEM, XRD, XPS und Raman‐Spektroskopie nachgewiesen wurden.</P>

A Four-Switch and Half-Bridge Boost Converter based BLDCM Drive System For the DC-Link Voltage Unbalancing Compensation

Sang-Hoon Park,Young-Hwan Ryu,Won-cheol Lee,Jung-Hyo Lee,Jae-Sung Yu,Young-Ryul Kim,Chung-Yuen Won 전력전자학회 2007 ICPE(ISPE)논문집 Vol.- No.-

This paper proposes a controller to compensate the DC-Link voltage unbalance in the BLDC motor drive system based on the four-switch and half-bridge boost converter. In this paper, we can see that the proposed feed?forward controller is useful for control of the neutral point voltage unbalance. The comparative experimental results show that the system became more robust by the feed-forward control of the neutral point voltage.

Reduced Mitochondrial Properties in Putative Progenitor/Stem Cells of Human Keratinocytes

( Sung Eun Chang ),( Young Mi Kim Pak ),( Hae Woong Lee ),( Jee Ho Choi ),( Eun Jeong Jeong ),( Seung Ho Choi ),( Hyo Won Chang ),( Yoo Sam Chung ),( Sang Yoon Kim ) 대한피부과학회 2009 Annals of Dermatology Vol.21 No.4

Background: The characterization of progenitor/keratinocyte stem cells (KSC) remains an unachieved goal. A previous study showed that rapid adhering cells to collagen IV had the characteristics of putative progenitor/KSCs. Objective: The purpose of this study was to investigate the genetic expression of rapid adhering cells compared to non adhering cells to determine the characteristic of KSCs. Methods: We isolated rapid adhering cells representative of KSCs from non adhering cells representative of transient amplifying cells. In addition, we differentiated cells from human tonsilar keratinocytes utilizing the adhering capability of the KSCs to collagen IV. Annealing control primer based differentially displayed polymerase chain reaction (PCR) was performed as well as Western blot analysis. Results: The levels of mitochondria- related gene expression were low in the rapid adhering cells compared to the non adhering cells. Mitochondrial complex I, COX IV, peroxiredoxins (I, II and IV) and mitochondrial membrane potential were all low in the rapid adhering cells compared to the non adhering cells. Conclusion: Using an adhesion method on human collagen IV-coated plates, our results suggest that reduced mitochondrial function may be an important characteristic of KSCs. (Ann Dermatol 21(4) 364~368, 2009)

Diagnosis and Follow-up US Evaluation of Ruptures of the Medial Head of the Gastrocnemius (“Tennis Leg”)

Hyo-Sung Kwak,Young-Min Han,Sang-Yong Lee,Ki-Nam Kim,Gyung Ho Chung 대한영상의학회 2006 Korean Journal of Radiology Vol.7 No.3

Objective: The purpose of this study was to demonstrate the ultrasonographic (US) findings of rupture and the healing process of the medial head of the gastrocnemius ("Tennis Leg"). Materials and Methods: Twenty-two patients (age range: 30 to 45 years) with clinically suspected ruptures of the medial head of the gastrocnemius were referred to us for US examination. All the patients underwent US of the affected limb and the contralateral asymptomatic limb. Follow-up clinical evaluation and US imaging of all patients were performed at two-week intervals during the month after injury and at one-month intervals during the following six months. Results: Of the 22 patients who had an initial US examination after their injury, partial rupture of the medial head of the gastrocnemius muscle was identified in seven patients (31.8%); the remaining 15 patients were diagnosed with complete rupture. Fluid collection between the medial head of the gastrocnemius and the soleus muscle was identified in 20 patients (90.9%). The thickness of the fluid collection, including the hematoma in the patients with complete rupture (mean: 9.7 mm), was significantly greater than that seen in the patients with partial tear (mean: 6.8 mm) (p < 0.01). The primary union of the medial head of the gastrocnemius with the soleus muscle in all the patients with muscle rupture and fluid collection was recognized via the hypoechoic tissue after four weeks. Conclusion: Ultrasonography is a useful imaging modality for the diagnosis and follow-up examination for the patients suffering with rupture of the medial head of the gastrocnemius.

Transarterial Chemoembolization Can Be Safely Performed in Patients with Hepatocellular Carcinoma Invading the Main Portal Vein and May Improve the Overall Survival.

Chung, Goh Eun,Lee, Jeong-Hoon,Kim, Hwi Young,Hwang, Sang Youn,Kim, Joon Suk,Chung, Jin Wook,Yoon, Jung-Hwan,Lee, Hyo-Suk,Kim, Yoon Jun Radiological Society of North America 2011 Radiology Vol.258 No.2

<P>Purpose: To determine the efficacy and safety of transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC) and main portal vein (MPV) invasion. Materials and Methods: This study was approved by the institutional review board, and the requirement to obtain informed consent was waived. The authors retrospectively assessed the electronic medical records of patients in whom HCC with MPV invasion was newly diagnosed from January 2004 to December 2007 at a single tertiary medical center. Patients with decompensated hepatic function were excluded. Outcomes of patients treated with TACE were compared with those of patients given supportive care according to Child-Pugh class. Results: One hundred twenty-five patients (104 men and 21 women; mean age, 55.7 years; age range, 33.4-83.0 years) were included. The median overall survival was 3.7 months (range, 0.2-33.3 months). Eighty-three of the 125 patients (66.4%) were treated with TACE and 42 (33.6%) received supportive care. Repeated TACE showed significant survival benefits compared with supportive care in patients with Child-Pugh class A (median survival, 7.4 months vs 2.6 months, respectively; P < .001) and class B (median survival, 2.8 months vs 1.9 months, respectively; P = .002) disease. Results of multivariate analysis showed that treatment with TACE (hazard ratio, 0.263; 95% confidence interval [CI]: 0.164, 0.424; P < .001) and Child-Pugh class A status (hazard ratio, 0.550; 95% CI: 0.368, 0.822; P = .004) were independent predictive factors of a favorable outcome. There were no procedure-related deaths within 4 weeks after TACE, and patient morbidity was 28.9% (24 of 83 patients). Conclusion: TACE can be performed safely and may improve the overall survival of patients with HCC and MPV invasion. © RSNA, 2011.</P>