• Journal of the Microelectronics and Packaging Society
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• v.24 no.1
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• pp.45-50
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• 2017

We investigated effect of Zn content on shear strengh of Sn-0.7Cu-xZn and OSP surface finished solder joints. Five pastes of Sn-0.7Cu-xZn (x=0, 0.5, 1.0, 1.5, 2.0 wt.%) solders were fabricated by mixing of solder powder and flux using planatary mixer. $180{\mu}m$ diameter solder balls were formed on OSP surface finished Cu electrodes by screen print method, and the reflow process was performed. The shear strength was evaluated with two high shear speeds; 0.01 and 0.1 m/s. The thickness of the intermetallic compound(IMC) layer was decreased with increasing Zn content in Sn-0.7Cu-xZn solder. The highest shear strength was 3.47 N at the Zn content of 0.5 wt.%. As a whole, the shear strength at condition of 0.1 m/s was higher than that of 0.01 m/s because of impact stress. Fracture energies were calculated by F-x (Force-displacement) curve during high speed shear test and the tendency of fracture energy and that of shear strength were good agreement each other. Fracture took place within solder matrix at lower Zn content, and fracture occured near the interface of OSP surface finished Cu electrode and solder at higher Zn content.

• Journal of Animal Science and Technology
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• v.51 no.5
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• pp.387-394
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• 2009

This study was carried out to screen and identify the chitinase and chitosanase producing microorganisms from the feces of calves medicated DFM sincluding chitin in order to do the immune fortification of Korean Native calves. Ten isolates were grown in the medium containing chitin and chitosan that had more than $10^5$ cfu/g in feces. Among these 10 strains, 2 strains (HANDI 110 and HANDI 309) had the chitinase activities and 2 strains (HANWOO and HANYOO) had the chitosanase activities in calves' feces. They showed no reaction in hemolysis tests by utilizing chitin and chitosan. The results from morphological, physicochemical and genetical identification indicated the HANDI 110 as a strain of Escherichia fergusonii, HANDI 309 was identified as a strain of Acinetobacter parvus, HANWOO was identified as a strain of Comamonas koreensis, and HANYOO as a strain of Chryseobacterium indologenes.

• Molecules and Cells
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• v.25 no.4
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• pp.559-565
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• 2008

Members of the TGA family of basic domain/leucine zipper transcription factors regulate defense genes through physical interaction with NON-EXPRESSOR OF PR1 (NPR1). Of the seven TGA family members, TGA4/octopine synthase (ocs)-element-binding factor 4 (OBF4) is the least understood. Here we present evidence for a novel function of OBF4 as a regulator of flowering. We identified CONSTANS (CO), a positive regulator of floral induction, as an OBF4-interacting protein, in a yeast two-hybrid library screen. OBF4 interacts with the B-box region of CO. The abundance of OBF4 mRNA cycles with a 24 h rhythm under both long-day (LD) and short-day (SD) conditions, with significantly higher levels during the night than during the day. Electrophoretic mobility shift assays revealed that OBF4 binds to the promoter of the FLOWERING LOCUS T (FT) gene, a direct target of CO. We also found that, like CO and FT, an OBF4:GUS construct was prominently expressed in the vascular tissues of leaf, indicating that OBF4 can regulate FT expression through the formation of a protein complex with CO. Taken together, our results suggest that OBF4 may act as a link between defense responses and flowering.

• Journal of Life Science
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• v.23 no.1
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• pp.1-7
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• 2013

Understanding salt tolerance mechanisms is important for the increase of crop yields, and so, several screening approaches were developed to identify plant genes which are involved in salt tolerance of plants. Here, we transformed the Arabidopsis cDNA library into a salt-sensitive calcineurin (CaN)-deficient ($cnb{\Delta}$) yeast mutant and isolated the colonies which can suppress salt-sensitive phenotype of $cnb{\Delta}$ mutant. Through this functional complementation screen, a total of 34 colonies functionally suppressed the salt-sensitive phenotype of $cnb{\Delta}$ yeast cells, and sequencing analysis revealed that these are 9 genes, including CaS, AtSUMO1 and AtHB-12. Among these genes, the ectopic expression of CaS gene increased salt tolerance in yeast, and CaS transcript was up-regulated under high salinity conditions. CaS-antisense transgenic plants showed reduced root elongation under 100 mM NaCl treatment compared to the wild type plant, which survived under 150 mM NaCl treatment, whereas CaS-antisense transgenic plant leaves turned yellow under 150 mM NaCl treatment. These results indicate that the expression of CaS gene is important for stress tolerance in yeast and plants.

• Molecules and Cells
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• v.24 no.2
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• pp.276-282
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• 2007

Protein phosphorylation is one of the major mechanisms by which eukaryotic cells transduce extracellular signals into intracellular responses. Calcium/calmodulin ($Ca^{2+}/CaM$)-dependent protein phosphorylation has been implicated in various cellular processes, yet little is known about $Ca^{2+}/CaM$-dependent protein kinases (CaMKs) in plants. From an Arabidopsis expression library screen using a horseradish peroxidase-conjugated soybean calmodulin isoform (SCaM-1) as a probe, we isolated a full-length cDNA clone that encodes AtCK (Arabidopsis thaliana calcium/calmodulin-dependent protein kinase). The predicted structure of AtCK contains a serine/threonine protein kinase catalytic domain followed by a putative calmodulin-binding domain and a putative $Ca^{2+}$-binding domain. Recombinant AtCK was expressed in E. coli and bound to calmodulin in a $Ca^{2+}$-dependent manner. The ability of CaM to bind to AtCK was confirmed by gel mobility shift and competition assays. AtCK exhibited its highest levels of autophosphorylation in the presence of 3 mM $Mn^{2+}$. The phosphorylation of myelin basic protein (MBP) by AtCK was enhanced when AtCK was under the control of calcium-bound CaM, as previously observed for other $Ca^{2+}/CaM$-dependent protein kinases. In contrast to maize and tobacco CCaMKs (calcium and $Ca^{2+}/CaM$-dependent protein kinase), increasing the concentration of calmodulin to more than $3{\mu}M$ suppressed the phosphorylation activity of AtCK. Taken together our results indicate that AtCK is a novel Arabidopsis $Ca^{2+}/CaM$-dependent protein kinase which is presumably involved in CaM-mediated signaling.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.195-198
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• 2006

Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.72-72
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• 2000

ITO(Indium-Tin-Oxide)는 n-type 전도 특성을 갖는 산화물 반도체로서 가시광 영역에서의 높은 광투과율 및 낮은 전기 비저항을 나타내기 때문에 태양전지, 액정디스플레이(liquid crystal display), 터치스크린(touch screen) 등의 투명전극 재료, 전계 발광(electroluminescent) 소자, 표면발열체, 열반사 재료 등 다양한 분야에 응용되고 있다. 본 연구에서는 타겟 제작에 드는 비용을 줄이고, 타겟 이용의 효율성을 높이기 위해 기존의 세라믹 타겟 대신 분말 타겟을 사용하여 유리 기판 상에 ITO 박막을 DC magnetron sputtering법에 의해 제조하고, 열처리 온도 및 열처리 분위기에 따른 ITO 박막의 전기적 광학적 특성을 조사하였다. 열처리 온도가 10$0^{\circ}C$이하인 경우 열처리하지 않은 시편과 동일하게 In2O3의 (411)면에 해당하는 peak가 관찰되었다. 그러나 20$0^{\circ}C$의 온도로 열처리 할 경우 (411)면 peak의 세기는 상대적으로 감소하고 대신 이전에 나타나지 않았던 (222)면에 대응하는 peak 세기가 현저하게 증가함을 알 수 잇다. 이것은 ITO 박막의 경정성장이 열처리 전 (411)면 방향으로 이루어지나 20$0^{\circ}C$의 온도로 열처리 후 재결정화에 의해 (222)면 방향으로의 우선방위를 갖고 성장함을 의미한다. 또한 주로 높은 기판온도에서 관찰되었던 (211), (400), (411), (440), (622)면 등에 해당하는 peak가 나타남을 볼 수 있었다. 열처리 온도를 더욱 증가시킴에 따라 결정구조에는 큰 변화 없이 (222)면 peak 세기가 증가하였다. 한편 열처리 온도를 더욱 증가시킴에 따라 (222)면 peak 세기가 상대적으로 조금 감소할뿐 XRD회절 결과에는 큰 변화를 관찰할 수 없었다. 이러한 결과로부터 기판을 가열하지 않고 증착한 ITO 박막의 재결정화에 필요한 최소의 열처리 온도는 20$0^{\circ}C$이며, 그 이상의 열처리 온도는 ITO박막의 결정구조에 큰 영향을 미치지 않음을 알 수 있었다. 열처리 전 비저항은 1.1$\times$10-1 $\Omega$-cm 의 값을 가지거나 10$0^{\circ}C$의 온도로 열처리함에 따라 9.8$\times$102$\Omega$-cm 로 약간 감소하였다. 열처리 온도를 20$0^{\circ}C$로 높임에 따라 비저항은 급격히 감소하여 1.7$\times$10-3$\Omega$-cm의 최소값을 나타내었다. 열처리 온도가 10$0^{\circ}C$인 경우 가시광 영역에서의 광투과율은 열처리하지 않은 시편과 비교해 볼 때 약간 증가하였다. 열처리 온도는 20$0^{\circ}C$로 증가시킴에 따라 투과율은 크게 향상되어 흡수단 이상의 파장영역에서 90% 이상의 투과율을 나타내었다. 이러한 광투과율의 향상은 앞서 증착된 ITO 박막이 열처리 중 재결합에 의해 우선 성장 방위가 (411)면 방향에서 (222)면 방향으로 변화되었기 때문으로 생각된다. 그러나 열처리 온도를 20$0^{\circ}C$이상으로 증가시켜도 광투과율은 큰 변화를 나타내지 않았다.

• Journal of Nutrition and Health
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• v.38 no.6
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• pp.445-454
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• 2005

The purpose of this study was to compare the validity of obese index among body mass index (BMI), waist to hip ratio (WHR), and waist circumference (WC) and to determine which is the best in relation to cardiovascular disease (CVD) risk in Korean elderly more than 65 ages. Data from the 1998 Korean Health and Nutrition Survey were used (n=1017). Anthropometric indices and CVD risk factors were measured, and chi-square test, analysis of variance following duncan's multiple range test, partial correlation analysis, and Receiver Operator Characteristic (ROC) curves were used in the analysis. Anthropometric values were decreased in both male and female when ages were goes up. In female elderly, it specially showed the characteristics of upper body fat and systolic blood pressure risk (p<0.05). Among life style factors the current smokers were prevalent in obese male (p<0.05), but not prevalent in female having obese or upper body fat. Also, person with upper body obesity have more exercise than that of normal group (p<0.01). Mean BMI values of the current smoker was lower than that of normal group in both sexes (p<0.01). Mean BMI value of person with other risk factors were higher than that of normal groups (p<0.05). Among 7 CVD risk factors in partial correlation analysis, WC had the highest correlation coefficient in 5 in male, whereas BMI in 4 in female. In ROC analyses of 12 risk factors and health conditions, the largest area under curve of obese indices for risk factors were WC>WHR>BMI in male and BMI>WHR>WC in female. The optimal cutoff values of each index (BMI : WHR : WC) for one or more risk factors were 19.02 : 0.84 : 71.3 in male and 19.04 : 0.88 : 85.6 in female. In conclusion, Most Korean elderly showed non-obese and abdominal obesity likewise other Asians. Also CVD risk factors were prevalent in Korean elderly within normal limits of obese indices. Therefore the upper body fat indices reflected in the aged whose muscle mass is replaced by fat must be used as an indicator of CVD risk together with BMI. Although WHR was the worst index based on partial correlation analysis and so located between BMI and WC in ROC curve analysis in both sexes, it need to be use with WC to screen the cardiovascular risk group.

• Journal of the Korean GEO-environmental Society
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• v.14 no.4
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• pp.53-58
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• 2013

The design for horizontal drain layer on soft ground starts from the decision that the material could be used or not, by verifying material condition in permeability of horizontal drain material according to the weight percent of the dry soil retained on #200 sieve. In the next step of the design, we estimate the thickness of horizontal drain layer to confirm trafficability of heavy machinery in construction work. Successively, the long-term functionality for good drainage of horizontal drain layer is checked and if needed, some means are considered. In this study, the system to recycle mixed coal ash in ash pond successfully as a horizontal drain material on soft ground is presented through the process and the result of its practical construction work. Namely, the pact is confirmed that mixed coal ash in ash pond should be sorted out by sieve screen to a certain extent and the remainders of this mixed coal ash on sieve openings be recycled, because the amount of finer particles than $75{\mu}m$ contained in mixed coal ash in ash pond is quite massive and irregular depending on the coal power plant or the location in same ash pond. In order to sort at large scale in situ, the dimension of a sieve squre hole and the sort-out method, etc. should be decided before the sort-out process. And, it is described that we need to manufacture classifier to sort out mixed coal ash in ash pond, too.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.165-173
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• 2021

Purpose : Myofascial decompression is frequently mentioned as a method applied to cupping. The purpose of this study is to evaluate and compare active range of motion (AROM), muscle strength, and functional movement by applying myofascial decompression to the hamstrings. Methods : This study evaluated AROM, muscle strength, and functional movement by applying active movement myofascial decompression and static myofascial decompression to the dominant leg, respectively, in a crossover design conducted with normal adults (n=21) in their average 20s enrolled at G University in G city, Gyeongsangbuk-do. Active movement myofascial decompression was implemented for five minutes at a rate of 100 bpm to make the beats in flexion and extension respectively. Static myofascial decompression was only performed for five minutes while at rest. All of these interventions were performed at a cupping depth of two mm. After a one-week washout period, static was applied again to compare the same dependent variables. Results : Regarding AROM and muscle strength, both groups showed significant differences in the before and after results (p<.05). However, in the Functional Reach Aspect and Single Leg Hop test, the active movement myofascial decompression group showed better results. There was no statistical difference between the Active movement myofascial decompression group and Static myofascial decompression group in any dependent variable (p<.05). Conclusion : As a result of this experiment, both active movement myofascial decompression and static myofascial decompression had a positive effect on dependent variable. Therefore this study is meaningful in that it is easier and simpler to see the effect on flexibility, muscle strength, and functional movement just by implementing movement myofascial decompression.