• Korean Journal of Microbiology
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• v.30 no.4
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• pp.260-264
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• 1992

Pseudotnorju.c sp. EL-071P degrading 2.4.5-trichlorophe~~oxyi~cetaicci d (2.3.5-T) was resistantto antibiotics: rifampicin. ampicillin. kanamycin and metal ions : Zn" and Cu".The plasmitl related to the degradation of 2.4.5-'r and rifa~npicin resistance was isolatecifrom the strain. Its size was about 40 Kb. As result of transforming the plasmid intoEsch~rirhiti coli MClOhl, it was confirmed that the plasmid ura.; related to 2.4.5-T degradation.The strain coulil grow in the various chlorinated aromatic analogs as the solc carbon source.In the case of chlorophcnols. the chlorinated mono-substituteti phenols were easily dcgradetlin the order ol' ortho-. ~ ~ a r um- ,c ~tu-position.T he 2.3.5-T mctaholism was inhibited by 4-chlorophenol of 2.4.5-7' analog. In non-chlorinateci aromatics. ~ C I I L O ~ I ~ Csa.l icylilte i~ndtoluene were uscd ax the carbon source by the strain and typestrain Acudonlotrtr.\ plrtirltrKCTC 1643 having clegrad;~bility of various aromatics. But naphtalene was usecl only bythe A~urlomonri.\ sp. EL-07 1 P.the A~urlomonri.\ sp. EL-07 1 P.

• Korean Journal of Materials Research
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• v.9 no.8
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• pp.768-774
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• 1999

Yttia-doped ceria-stabilized ziconia polycrystals(Ce-TZP) was prepared by dipping method and its microstructure was investigated. By controlling doped-yttria content and annealing condition, yttria-doped Ce-TZP showed the microstructure with irregular grain shape and undulated grain boundary. Irregularity of grain shape increased with the amount of yttria doped, and severe undulated grain boundary was observed mainly at the surface region. In the case of yttria-doped Ce-TZP annealed at 1$650^{\circ}C$ for 2h after two dipping times into yttrium nitrate solution of 0.2M, it showed irregular grain shape both at the surface and at the interior region as well as the most severe irregularity. Hot pressed specimen had mean grain size of 0.3$\mu\textrm{m}$ and undulated grain boundary. All specimens with irregular grain shape were retained the tetragonal phase. The fracture toughness of yttria-doped Ce-TZP with irregular grain shape was over the value of 17.6MPa.m(sup)1/2.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.89-96
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• 1982

The purpose of this study is to identify the phases of four different types, low-copper lathe cut (Type II, class 1) and spherical (Type II, class 2) amalgam alloys which are made by Caulk company and high copper Dispersalloy (Type II, class 3) made by Johnson & Johnson and Tytin (Type I, class 2) made by S.S. White and to determine the Vickers hardness number on the individual phase and four different types of dental amalgam. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (De Trey), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12mm in height and was pressed by the Instron Universal Testing machine (Model 1125) at the speed of 1mm/minute with 143$kg/cm^2$ according to the A.D.A. Specification No. 1. The Specimen removed from the mold, mounted and stored in the room temperature for 7 days. The speciman was polished with the emery paper from #220 to #1200 and finally on the polishing cloth with 0.3 and 0.05 um $Al_2O_3$ powder suspended in water. And then each specimen was etched by Allan's method and washed with Sodium Bisulfinite for 30 seconds. Finally differentiation and metallography on each phase were obtained by using metallographical microscope (Versamet, Union) and microhardness was obtained by using microhardness tester (MVH-2, Torsee). The results were as follows: 1. In the low-copper amalgam, the ${\gamma}$, ${\gamma}_1$ and ${\gamma}_2$ phase were observed and in the high-copper amalgam, the ${\gamma}$, ${\gamma}_1$. ${\epsilon}$ and ${\eta}$ phases were observed but ${\gamma}_2$ phase was not observed. 2. Among the microhardness of each amalgam phase measured under pressing a vickers diamond indenter with 2.0gm load for 30 seconds, e phase has the highest V.H.N (314 ${\pm}$ 20), and in low-copper amalgam 12 phase has the lowest V.H.N. (29${\pm}$1) and ${\eta}$ phase which was observed in high-copper amalgam has 230${\pm}$13 V.H.N and this phase is considerd to contribute to strengthen the handness in amalgam. 3. The V.H.N. measured under pressing a Vickers diamond indenter with 300.0gm load for 30 seconds in low-copper amalgam was lower than that of high-copper amalgam.

• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.942-947
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• 2001

Thickness dependence of orientation on piezoelectric and electrical properties was investigated by PZT (52/48) films by diol based sol-gel method. The thickness of each layer by spinning at one time was $0.2{\mu}m$ and crack-free films could be successfully deposited on 4 inches Pt/Ti/$SiO_2$/Si substrates by 0.5 mol solutions in the range from $0.2{\mu}m$ to $3.8{\mu}m$. Excellent P-E hysteresis curves were achieved, which were attributed to the well-densified PZT films and columnar grain without pores or any defects between interlayers. The (111) preferred orientation of films were shown in the range of thickness below $1{\mu}m$. As the thickness increased, the (111) preferred orientation disappeared from $1{\mu}m$ to $3{\mu}m$ region, and the orientation of films became random above $3{\mu}m$. Dielectric constants and longitudinal piezoelectric coefficient, $d_{33}$, measured by pneumatic method were saturated around the value of about 1400 and 300 pC/N respectively above the thickness of $1{\mu}m$.

• The Korean Journal of Physiology
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• v.17 no.1
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• pp.45-54
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• 1983

Contractile responses of myocardium and vascular smooth muscle to angiotensin II were studied in isolated rabbit papillary muscles and aortic helical strips, with respect to the sensitivity and the mechanism of action. All experiments were performed in $HCO-_3\;-buffered Tyrode solution which was aerated with $3%\;CO_2-97%\;O_2$ and kept pH 7.35 at $35^{\circ}C$. Action potentials were measured by conventional microelectrode technique in the papillary muscles. Helical strips of vascular smooth muscle were prepared from the descending thoracic aorta of the rabbit. Angiotensin II elicited a positive inotropic effect in doses from $10^{-8}$ to $10^{-6}\;M$, and this effect was dose-dependent and characterized by a symmetrical increase of maximum dP/dt during contraction and relaxation phase. Slow responses (or slow action potentials) were induced by A. II $(10^{-6}\;M)$ in the papillary muscle hypopolarized by 27 mM $K^+$. These A. II-induced slow action potentials were eliminated by verapamil (2 mg/l), but not affected by propranolol $(10^{-5}\;M)$. In aortic helical strips, contractile force was increased dose-dependently in the range of $10^{-10}{\sim}10^{-7}\;M$ A. II. $ED_{50}$ in aorta was $3{\times}10^{-9}\;M$ A. II, whereas that in paillary muscle was $2.5{\times}10^{-7}\;M$ A. II. A. II contracted vascular smooth muscle in depolarizing concentration of $K^+$ (100 mM $K^+$), and also produced a sustained contraction even in the presence of verapamil and regitine. The results of this experiment suggest that the primarily important physiological role of A. II is the action on the blood vessel, and the positive inotropic effect of A. II in papillary muscle results from the increase of slow inward $Ca^{++}$ current, and that A. II-induced contraction of aorta is independent of transmembrane potential and associated with promoting bet transmembrane $Ca^{++}\;-influx$ and the mobilization of cellular $Ca^{++}$.

• The Korea Journal of Herbology
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• v.30 no.6
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• pp.63-68
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• 2015

Objectives : Gastric lesions affect many people around the world and their development are results of the imbalance between destructive and protective factors in the gastric mucosa. Lycium chinense has been widely used as a traditional Korean medicine, it was recently reported that they have potent anti-inflammatory effects in chronic hepatitis models. Therefore, this study aimed to investigate the anti-inflammatory activity of Lycium chinense extract (LCE) on HCl-Ethanol induced gastric lesion mice.Methods : The ICR mice were divided randomly into five groups of six animals each. Group A was normal mice, and group B was treated orally with 0.5 ml 150 mM HCl-60% Ethanol. Mice in group C and D were pre-treatment of LCE (100 mg/kg and 200 mg/kg bodyweight, p.o before HCl/ethanol treatment) and group E was orally administered sucralfate (10 mg/kg).Results : 150mM HCl/60% ethanol-induced gastric mucosal injury mice were ameliorated mucosal damage upon histological evaluation by treatment of LCE. Pre-treatment of LCE attenuated reactive oxidative species (ROS) and produces peroxynitrite (ONOO^-) in stomach tissues. As results of stomach protein analyses, LCE effectively reduce inflammatory-related factors such as cyclooxygenase-2 (COX-2), tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6) in gastric lesion mice. In addition, nuclear factor kappa B (NF-κB) and inhibitor of phosphorylation of nuclear factor kappa B (p-IκB) were down-regulated in LCE-administrated gastric lesion mice.Conclusions : Our discovery supports that the therapeutic activity of LCE ameliorate the development of gastric lesion via suppressing the oxidative stress and gastric partial inflammation induced by 150 mM HCl/60% ethanol.

• Journal of Embryo Transfer
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• v.18 no.1
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• pp.15-25
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• 2003

발생학에서 키메라(chimera)는 2개 이상의 다른 유전자형의 세포, 또는 다른 종의 세포로부터 만들어진 1개의 생물개체를 뜻하는 말로, 이는 초기 수정란의 발달과 포유류의 분화를 연구하는데 이용되고 있다. 키메라를 만드는 방법에는 할구와 내세포괴를 응집시키는 방법과 배반포 내에 여러 종류의 세포를 주입하는 방법이 있다 본 실험에서는 서로 다른 두 가지 방법의 활성화 처리법, 즉, ionomycin 처리 후 Cycloheximide (CHX) 또는 6-Dimetylaminopurine (6-DMAP)에 따른 단위 발생란의 분할과 단계적인 발달율을 살펴 보고자 하였으며, 서로 다른 방법에 의해 생산된 단위발생란 유래의 할구와 체외수정란 유래 할구를 응집하여 키메라 수정란(chimeric embryo)를 만든 후 체외수정란과 발달율을 비교해 보았다. 도축장 유래의 난소에서 난자를 채취하여 체외에서 22~24시간 성숙시킨 후 난구세포를 제거하고 metaphase II 단계의 난자를 5 $\mu$M ionomycin에 4분간 처리한 후, 10 $\mu$g/ml CHX/5 $\mu$g/ml cytochalasin B (CCB)에 5시간 또는 1.9 mM 6-DMAP에 4시간 처리하여 분할율과 배반포기 발달율을 비교 조사하였다. 난자 분할율에서는 체외수정란과 6-DMAP처리 단위 발생란에서 각각가 83.7 와 85.5%로 CHX/CCB 처리 단위발생란의 57.9%보다 유의적으로 높게(P<0.05) 나타났으며, 배반포기 발달율에 있어서는 체외수정란의 발달율이 27.8%로 6-DMAP처리 활성란 12.3%와 CHX/CCB 처리 활성란 5.3%보다 유의적으로 높게 (P<0.05) 나타났다. 키메라 수정란(chimeric embryo)은 서로 다른 두 가지 처리에 의해 생산된 단위발생란의 할구 2개와 체외수정란 유래의 할구 2개를 빈 투명대 내에서 응집시켜 제조하였다 빈 투명대 내에 키메라 수정란(chimeric embryos)의 8 세포기까지의 발달율은, 체외 수정란 할구 2개와 CHX/CCB 처리에 의한 할구 2개를 응집한 그룹은 46.1%, 체외 수정란 할구와 6-DMAP 유래 할구 2개를 응집한 그룹은 52.8% 였으며, handled control은 54.7%로 체외 수정란 77.7%에 비해 유의적으로 낮게(P<0.05) 나타났다. 배반포기까지의 발달율은 체외 수정란과 CHX/CCB에 의해 생산된 키메라 수정란(chimeric embryo)은 12.8%, 체외 수정란과 6-DMAP에 의한 키메라 수정란(chimeric embryo)은 18.8%로 handled control의 21.4%에 비해 유의적으로 낮았으며(P<0.05), 이들 키메라 수정란(chimeric embryos)은 체외 수정란의 34.9%에 비해 유의적으로 낮게(P<0.05)나타났다. 6-DMAP 처리 단위발생이 유기된 수정란 할구 2개와 체외수정란의 할구 2개의 응집에 의한 키메라 수정란(chimeric embryos)의 발달율이 CHX/CCB와 체외수정란의 응집에 의한 키메라 수정란(chimeric embryos)에 비해 다소 높게 나타났으나, 유의적인 차이는 없었다. 본 실험의 결과 서로 다른 방법에 의한 단위 발생란 유래의 할구와 체외 수정란 유래의 할구가 응집에 의한 재조합이 가능하였고 이들을 체외에서 배양하여 배반포기의 수정란까지 발달시켰다.

• Land and Housing Review
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• v.4 no.3
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• pp.279-286
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• 2013

Driving a prefabricated pile is the efficient construction method with low cost and excellent bearing capacity charateristics. But pile drinving method has often been changed to bored pile method with mechanical boring due to the unexpected problems occurred in the various domestic ground condition with landfill. So, pile driving method has more uncertainty than the Bored Pile method. This paper proposed LRFD design value which is one of limit states design method for the PHC driven pile used as building foundation to guarantee the reliable design with reduced uncertainty. This paper analysed 221 dynamic load test results(E.O.I.D : 93, Resrike : 128) and the different methods of estimating bearing design(Meyerhof method & SPT-CPT conversion method), and proposed LRFD value for each design reliability Index 2.33 and 3.0 for PHC driven pile. LRFD value of PHC driven pile represents 0.43~0.55 for Meyerhof method and 0.40~0.49 for SPT-CPT conversion method according to the deign reliability index.

• Journal of the Korean Geosynthetics Society
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• v.18 no.3
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• pp.45-53
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• 2019

In this study, it was analyzed the cases of bored PHC piles designed for the building foundations. The overall length of the piles varies within a maximum of 35 m. However, the average length was 17.0 to 18.9 m depending on the kind of the bedrock, with no significant difference. The socket length entered into the bedrock was designed with approximately 58% of the whole piles being 1m, the minimum length of the specification, and up to 5m. Although the range in design efficiency was very large, on average it was about 70%, consistent with the usual known extent. Applications with low design efficiency were mainly shown on the foundation of low-rise buildings or rides with low design load. On the weathered rock, the design load, which governs the design result was widely distributed at 65 to 97% of allowable bearing capacity of ground. The ratio of allowable axial load of piles to allowable bearing capacity of ground is also widely distributed between 36 and 115%, so optimization efforts are required along with design efficiency. On the other hand, the allowable bearing capacity on the soft or hard rock was highly equal, mostly within 90% of the allowable axial load of piles. In the design, the end bearing resistance averaged over 75% of the allowable bearing capacity. However, the results of the dynamic pile load test show that the end bearing resistance was predominant under the E.O.I.D conditions, and in some cases, the end bearing resistance was at least 25% under the restrike conditions.

• Journal of Practical Agriculture & Fisheries Research
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• v.12 no.1
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• pp.137-150
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• 2010

Traditionally, like many people in mountain region of the Himalaya, the Lwang communities depend on mix of subsistence agriculture, animal husbandry, and seasonal migrant labor for their livelihoods. These traditional systems are characterized by low productivity, diverse use of available natural resources (largely for home consumption), limited markets, and some aversion for innovation. The potential to generate wealth through commerce has largely been untapped by these mountain residents and thus is undervalued in local and national economies. Introduction of organic tea farming is a part of Lwang community's several initiatives to break the vicious poverty cycle Annapurna Conservation Area Project (ACAP) played facilitating roles in all their efforts since beginning. In five years, the tea plantation emerged as a new means for secured a livelihood. This study aims to analyze the current practices in tea farming both in terms of farm management and soil nutrient status(technical) and the prosperity of the tea farmers (social). The technical aspect covers the soil and tea leaf analysis of various nutrients contents in the soil and tea leaf. Originally, the technical aspect of the study was not planned but later during the consultation with the advisor it was taken into consideration which added value to the research study. The sample were collected from different locations and analyzed on the field itself. The other part of the study i.e. the social aspect was done through questionnaire survey and focus group discussion. the tea farming provided them not only a new opportunity but also earned an identity in the region. This initiative was undertaken as a piloting measure. Now that the tea is in production with processing unit established locally, more serious consideration has to be given for better yield and economic prosperity. This research finding will help the community to analyze their efforts and make correction measures in tea garden management and application of fertilizer. It is also expected to fill up the gaps of knowledge and information required to reduce economic stresses and enhance capacity of farmers to make the tea farming a sustainable and beneficial business. The findings are expected to Sustainability of organic tea farming has direct impacts on biodiversity conservation compared to the other traditional farming practices that are more resource intensive. The study will also contribute to identify key action points required for reducing poverty while conserving environment and enhancing livelihoods