• Journal of Biosystems Engineering
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• v.1 no.1
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• pp.1-6
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• 1976

This paper is the third one of the study on balanced type oscillating mole-drainer, the first one was presented in No 9. Gyeongsang College Report and the second one in Vol. 17, No.4 of the KSAE. In the first part of this study, the characteristics of traction forces between the nonoscillating earth working equipments and oscillating ones was compared. A model of the balanced type oscillating mole-drainer, which composed of a mechanism that may reduce the machine vibration, was designed following the dimensional analysis and similitude technique. The model test was carried out to clarify the balancing mechanism of the oscillating parts and other parts of the machine. In the light of the results from the model tests, a prototype machine was made for experimental purpose. Results from the field test by a reported in the near future. In the second report, the model tests were carried out under the same soil conditions, i.e, . oscillating frequency, running velocity, and oscillating amplitude, etc. It was clear that use of balanced type oscillating model could substantially reduce the vibration of the whole system of the machine, when compared with the nonoscillating type model. In this paper(the third report), results of investigation on the traction force, power requirement, and moment. etc, is presented. Analysis of variance technique was used for analyzing the effect of the frequency, amplitude, and running velocity on the draft force, torque, power requirements, and moments. The results obtained from the model tests are as follows, 1) By practicing a balanced-type oscillating mole-drainer, it was possible to reduce the traction resistance by 55.1-61. 2 percent of traction resistance, however, was 1.75 - 1.95 times greater than the value of resistance which was induced by use of a mole-drainer with single bullet. The resistance of rear shank against soil was considered as a main causing factor of the above results. 2) As the oscillation frequency was increased, the traction resistance was decreased. Considering on the effect of oscillation the greater the amplitude, and the slower the running velocity was, the greater the reduction ratio of traction resistance was. 3) The ratio of the traction resistance of oscillating mole-drainer to that of non-oscillating one could be represented as a function of dimensionless variable (V/$Af$). The results from the tests were well agreed with the reported results from the experim ents on oscillation plow or hoe. 4) By taking a lower value of (V/$Af$), reducing the traction resistance was possible. This fact meant, however, that the efficiency of mole drain practice would be lower. 5) It was experimentally confirmed under the same condition of soil that the variable (R/$rD1^3$) could be represented as a function of a variable($V^2/gD$) when a non\ulcornerocillating mole-drainer was used. 6) When a oscillating mole-drainer was used, the variable(R/$rD_1^{3}$) could be represented as a function of two variables ($v^2/gD_1$) and (V^2/gD_1$). 7) The torque was not affected by a change of frequency. However, a relation of proportionality existed between torque and amplitude, running velocity, and ratio of bullet diameter. When a balanced type oscillating mole-drainer with two bullets was used, torque was increased by 52.8-78. 4 percent and total power requirement was also increased. 8) Total power requirement was increased linearly in accordance with the increasing frequency, 41.96 percent of total power was used for oscillating action. The magnitude of total power requirement was 1. 8-9. 4 times greater than that of a non-oscillating mechanism. In the view point of power requirement, it was not advisable to increase the frequency, amplitude, running velocity, and ratio of bullet diameter at the same time. 9) Only the positive moment occured in the rear shank. Change of the diameter of a rear bullet, could not affect the balancing against the soil resistance. It was necessary for rear bullet to have a large resistance against soil only when the rear bullet was in backward motion. 10) Within an extent of the experimental base, optimum limits for several design factors were A=0.5cm, $f$=22.5Hz, V=O. 05m/sec, and $\lambda$=1.0 By adapting these values traction resistance was reduced by 40 percent and vibration acceleration wa s reduced by 60 percent. Even though the total , power requirements for operating a balanced type oscillation mechanism was greater ~than that of non-oscillating one, using a oscillating mechanism would be more effective. Because a balanced type oscillating mechanism is used, tractive resistance will be reduced and then the lighter . tractive equipment could be used.

• The Korean Journal of Nuclear Medicine
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• v.39 no.3
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• pp.182-190
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• 2005

Purpose: There are differences between Standard Uptake Value (SUV) of CT attenuation corrected PET and that of $^{137}Cs$. Since various causes lead to difference of SUV, it is important to know what is the cause of these difference. Since only the X-ray CT and $^{137}Cs$ transmission data are used for the attenuation correction, in Philips GEMINI PET/CT scanner, proper transformation of these data into usable attenuation coefficients for 511 keV photon has to be ascertained. The aim of this study was to evaluate the accuracy in the CT measurement and compare the CT and $^{137}Cs$-based attenuation correction in this scanner. Methods: For all the experiments, CT was set to 40 keV (120 kVp) and 50 mAs. To evaluate the accuracy of the CT measurement, CT performance phantom was scanned and Hounsfield units (HU) for those regions were compared to the true values. For the comparison of CT and $^{137}Cs$-based attenuation corrections, transmission scans of the elliptical lung-spine-body phantom and electron density CT phantom composed of various components, such as water, bone, brain and adipose, were performed using CT and $^{137}Cs$. Transformed attenuation coefficients from these data were compared to each other and true 511 keV attenuation coefficient acquired using $^{68}Ge$ and ECAT EXACT 47 scanner. In addition, CT and $^{137}Cs$-derived attenuation coefficients and SUV values for $^{18}F$-FDG measured from the regions with normal and pathological uptake in patients' data were also compared. Results: HU of all the regions in CT performance phantom measured using GEMINI PET/CT were equivalent to the known true values. CT based attenuation coefficients were lower than those of $^{68}Ge$ about 10% in bony region of NEMA ECT phantom. Attenuation coefficients derived from $^{137}Cs$ data was slightly higher than those from CT data also in the images of electron density CT phantom and patients' body with electron density. However, the SUV values in attenuation corrected images using $^{137}Cs$ were lower than images corrected using CT. Percent difference between SUV values was about 15%. Conclusion: Although the HU measured using this scanner was accurate, accuracy in the conversion from CT data into the 511 keV attenuation coefficients was limited in the bony region. Discrepancy in the transformed attenuation coefficients and SUV values between CT and $^{137}Cs$-based data shown in this study suggests that further optimization of various parameters in data acquisition and processing would be necessary for this scanner.

• Natural Product Sciences
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• v.11 no.1
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• pp.45-49
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• 2005

Previously, a flavonoid fraction, which consisted mainly of protocatechuic acid, fustin, fisetin, sulfuretin, and butein, here named RCMF [${\underline{R}}hus$ verniciflua Stokes (RVS) ${\underline{c}}hloroform-{\underline{m}}ethanol\;{\underline{f}}raction$], was prepared from a crude acetone extract of RVS which is traditionally used as a food additive and as an herbal medicine. In the present study, we investigated the effects of $TNF-{\alpha}$ on RCMF-induced growth inhibition and apoptosis induction using human osteosarcoma (HOS) cells. The results from tritium uptake and MTT assays showed that $TNF-{\alpha}$ treatment itself (10 ng/ml) did not induce any cytotoxicity, but it actively accelerated RCMF-mediated cytotoxicity of HOS cells. RCMF-induced cytotoxicity and its facilitation by $TNF-{\alpha}$ was verified to be apoptotic, based on the increased DNA fragmentation and low fluorescence intensity in nuclei after propidium iodide (PI) staining of HOS cells. This speculation was further demonstrated by monitoring the Annexin V/PI double staining which could discriminate the difference between apoptotic and necrotic deaths. Collectively, our findings indicate that $TNF-{\alpha}$ accelerates RCMF-induced cytotoxicity in HOS cells.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.10
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• pp.1377-1385
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• 2009

Effect of inclusion of hard vs. soft wheat bran with different particle size on diet digestibility, growth performance and some slaughter traits was evaluated in fattening rabbits. Four isonitrogenous and isocaloric diets were used according to the origin of wheat bran (hard (HWB) - Triticum durum - and soft (SWB) - Triticum aestivum) combined with wheat bran particle size sieved by 2 mm (fine: 2) or by 8 mm (coarse: 8) in a bifactorial (2${\times}$2) study. A growth trial was conducted to measure the effect of treatments on performance in one hundred and twenty New Zealand White${\times}$Californian rabbits fed experimental diets from 50 to 87 days of age. Faecal apparent digestibility was determined within the last week in twenty animals per diet. Digestibility of nutrients was higher (p<0.05) in the diet containing HWB2, except for crude protein, ether extract and ash, than fine and coarse soft wheat bran diets. Final live weight, feed intake and feed consumption of rabbits on the diet with fine hard wheat bran were higher and resulted in greater daily weight gains (p<0.01) than for animals on the other diets. The slaughter yield and percentage value of organs were not significantly (p>0.05) affected by the diets fed; however, the diet containing fine hard wheat bran led to lower (p<0.05) percentages of skin, abdominal fat and carcass drip loss than the other dietary treatments. It is concluded that fine hard wheat bran can be better included in the diet than soft wheat bran to maximize growth performance without affecting carcass traits of fattening rabbits.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.734-736
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• 2012

Cadmium telluride (CdTe) films have been prepared on Corning 7059 glass, molybdenum (Mo), and polyimide (PI) substrates by r.f. magnetron sputtering technique. The influence of the sputter pressure on the structural and optical properties of these films was evaluated. In addition, a comparison of the properties of the films deposited on fferent substrates was performed.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.10
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• pp.1483-1489
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• 2016

Most of amino acid (AA) digestibility values for feed ingredients are obtained using pigs cannulated in the distal ileum. The ileal-cannulated pig model uses pigs older than six weeks due to difficulties related to implanting the T-cannula in distal ileum of younger pigs and complications during the post-surgical recovery. However, to properly formulate the diet of weaned pigs, the nutritive value of feed ingredients should be determined with younger pigs. Thus, 25 weaned pigs were used to determine the apparent total tract digestibility (ATTD) of nutrients, energy, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) ileal AA digestibility of broken rice (BR), with or without multicarbohydrase (MC) and phytase (Phy) supplementation. Piglets were weaned at 23 d of age and individually housed in digestibility cages until 45 d of age. The trial consisted of 7 d of adaptation to the experimental diets and 3 d of excreta (feces and urine) collection. Ileal digesta was collected at slaughter (about 6 weeks of age). A completely randomized experimental design was used to determine the effects of MC and Phy. Reference diets (RD, 5% casein) was replaced by 30% of BR with or without MC, Phy, or MC+Phy. The RD was used to quantify endogenous AA losses. BR with Phy supplied had increased the ATTD of dry matter (p<0.05) and SID of histidine (p = 0.05), arginine, leucine, lysine, valine, alanine, and proline (p<0.05). BR with MC had been increased digestible energy and protein and SID for histidine (p<0.05). There was no interaction between Phy and MC on the BR nutrient digestibilities. Standardized amino acid digestibilities of BR, without enzymes, were lower than those values reported in the literature. The MC and Phy improved the digestibility of some nutrients and energy of BR in post-weaned piglet diets.

• Electrical & Electronic Materials
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• v.10 no.5
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• pp.467-472
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• 1997

In this study, we investigated the thickness dependence of thermal bleaching(TB) effect as well as photo-induced scalar phenomena, such as photodrakening(PD) effect and photorefraction(PR) change, in chalcogenide A $s_{40}$ G $e_{10}$S $e_{15}$ $S_{35}$ thin films. We found that when these films were exposed for 15 minutes using blue-pass filtered Hg lamp(~4300$\AA$) after annealing for 30 minutes around the glass transition temperature Tg(20$0^{\circ}C$), the refractive index change ($\Delta$n) was varied up to 0.02~0.46 according to each thickness condition and the optical energy gap ($\Delta$ $E_{op}$ ) was shifted to a longer wavelength of approximately 0.67eV, especially for 1000$\AA$-thickness. Also, the TB PD effects have been understood by the results related to optical absorption characteristics. The TB effect could be estimated as increasing the stabilization of amorphous chalcogenide films since absorption slope of extended regions(U) was not changed by annealing. On the other hand, the PD effect could be understood as due to the enhancement of disorder since U and the slope of Urbachs tail(1/F) around an absorption edge were decreased by exposing.ing.n edge were decreased by exposing.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.2
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• pp.133-145
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• 1998

$Ca^{2+}-signals$ in endothelial cells are determined by release from intracellular stores and entry through the plasma membrane. In this review, the nature of $Ca^{2+}$ entry and mechanisms of its control are reviewed. The following ion channels play a pivotal role in regulation of the driving force for $Ca^{2+}$ entry: an inwardly rectifying $K^+$ channel, identified as Kir2.1, a big-conductance, $Ca^{2+}-activated$ $K^+$ channel (hslo) and at least two $Cl^-$ channels (a volume regulated $Cl^-$ channel, VRAC, and a $Ca^{2+}$ activated $Cl^-$ channel, CaCC). At least two different types of $Ca^{2+}$-entry channels exist: 1. A typical CRAC-like, highly selective $Ca^{2+}$ channel is described. Current density for this $Ca^{2+}$ entry is approximately 0.1pA/pF at 0 mV and thus 10 times smaller than in Jurkat or mast cells. 2. Another entry pathway for $Ca^{2+}$ entry is a more non-selective channel, which might be regulated by intracellular $Ca^{2+}$. Although detected in endothelial cells, the functional role of trp1,3,4 as possible channel proteins is unclear. Expression of trp3 in macrovascular endothelial cells from bovine pulmonary artery induced non-selective cation channels which are probably not store operated or failed to induce any current. Several features as well as a characterisation of $Ca^{2+}$-oscillations in endothelial cells is also presented.

• Journal of Embryo Transfer
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• v.9 no.3
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• pp.243-247
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• 1994

최근 의약적으로 유용한 단백질을 대량 생산키 위한 실현 가능한 방법이 유전자변환 가축의 이용과 관련되어 발전되어 왔다. 이러한 유전자 변환동물은 이종의 단백질을 유즙속으로 분비시키는 생체반응기로서 이용되고 있다. 이러한 전략적 목적을 위해 현재 유전자 변환동물의 생산을 위한 이용에 있어 여러 가지 방법들이 보고되고 있다. 그러나 ES 세포의 사용이 이러한 방법들 사이에서 가장 실질적인 것으로 추정되고 있다. 본 실험에서는 유전자 구축을 위해 사람 황체 호르몬(human luteinizing hormone; hLH)의 전사를 유도하기 위해 각각 2.2 및 0.5 kb의 토끼 $\beta$-casein pronoter 단편을 이용하여 생쥐의 유선에 hLH를 발현시키도록 조절하고 발현이 thynidine kinase(TK) pronoter에 의해 좌우되는 neo 유전자를 selectable marker로서 plasnid속에 삽입하였다. 그 결과 생긴 구축 유전자는 각각 pCas 2.2와 pCas 0.5로 명명하였다. 구축된 유전자로 2$\times$107의 TT-2 ES세포를 170V, 550$\mu$F로 100$\mu$g의 선상 plasmid에 의해 electroporation 시켰다. 감염된 colony들은 250$\mu$g/$m\ell$ G418을 함유하는 ESM 배양액에서 선별 7일 이후에 회수하여 성공적으로 감염된 ES세포는 PCR 및 Southern blot에 의해 확인되었고 그들 중 나머지는 trypsin 처리 후 각각 미세조작과 공배양 기술을 사용하여 ICR 생쥐의 8세포기 수정란 속에 도입하였다. 결국 24시간 동안 37$^{\circ}C$, 5% $CO_2$에서 배양된 배반포를 chimera의 생산을 위해 위임신 유기된 G418 선발처리 이후 400 및 275개의 ES 세포 colony가 생존하였으며, 3개의 ES 세포으 colony 의 genome 속에 임의적으로 plamid가 삽입된 것을 Southern blot에 의해 확인되었다. 총 13 chimera 생쥐가 3 colony로부터 생산되었으나 germ-line chimera는 현재 조사중이다. chimera 생산빈도는 공배양 기술보다 주입방법에서 현저히 높았다.

• BMB Reports
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• v.44 no.4
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• pp.244-249
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• 2011

The quality of a phage-displayed antibody library deteriorates with clonal variations, which are caused by differentially expressed Escherichia coli antibody genes. Using the human Fab SP114 against the pyruvate dehydrogenase complex-E2 (PDCE2), we created four E. coli TOP10F' clones with a pCMTG phagemid encoding Fab-pIII (pCMTG-Fab), Fd ($V_H+C_{H1}$)-pIII (pCMTG-Fd), or light chain (L) (pCMTG-L), or the vector only (pCMTG-${\Delta}Fab$) to investigate the effect of clonal variations in a defined manner. Compared to the others, the E. coli clone with pCMTG-Fab was growth retarded in liquid culture, but efficiently produced phage progenies by Ex12 helper phage superinfection. Our results suggest that an antibody library must be cultured for a short duration before helper phage superinfection, and that the Ex12 helper phage helped to alleviate the detrimental effect of clonal variation, at least in part, by preferentially increasing functional phage antibodies during phage amplification.