• Clinical and Experimental Reproductive Medicine
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• v.16 no.2
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• pp.139-146
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• 1989

The purpose of this study was to examine the qualitative variation of human fetal-cord sera (HCS) and to accept the sera in human lVF-ET program. One hundred and sixteenth RCS were tested with 1772 2-cell embryos of F1 (C57BL x CBA) virgin mice, Ten to sixteenth embryos were cultured in m-KRB medium with a aliquot of each serum (10%, v/v) or with bovine serum albumin(O.4%, w/v) as a control medium. Embryonic development were recorded at every 24hr for 4 days by such events as cellular compaction, cavitation, and hatching. In the control groups of eight assays, 98.1%(106/ 108) of 2-ce1l embryos developed above expanded blastocyst and the embryonic development was unified through the tests. But the developmental pattern in medium with each serum was various. Namely, the sera that supported development of 100% 2-cell embryos to above morula, early blastocyst, expanded blastocyst and hatching blastocyst was 45,7%(53/116) , 35.3%(41/116), 15.5%08/116.) and 6.9-%(8/116), respectively. And the sera that supported development of above 80% 2-cell embryos to the each embryonic stage was 92.2% (107/116), 83.6%(97/116), 63.8%(74/116) and 36.2%(42/116), respectively. Meanwhile two kinds of toxic pattern to the embryonic development were observed in some sera. The first pattern is that some sera arrested development of most embryos in pre- or post-stage of morula or blastocyst. The second pattern is that some sera promoted or arrested a part of embryos in the same dish. The ability of serum was depended on the batch of serum. Finally we could accept 69%(80/116) of the tested sera for human IVF-ET program. The base line for acceptance was the ability that supported above 80% 2-ce1l embryos to blastocyst. But some deterious sera were contained in this range. We cut off about 10% of the sera (83.6% , 97/116) that passed the baseline. This final percent of sera was similar to that of grade N of this study.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1140-1150
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• 2009

Forage diets provide good quality carcasses in sheep but very little is known in tropical goats. An experiment was designed with Creole male goats using grass-based systems to assess carcass yield, scores, cuts and composition. After weaning (84 d, 9.2 kg LW) two modes of forage feeding were compared with two replicates of each. Feeding groups were: PF for animals reared at pasture (n = 62) and IF when reared indoors (n = 60). Given that forage finishing will result in low ADG it appeared necessary to study different fattening lengths. The kids were equally divided into 4 groups: group A (n = 32), 4mo after weaning; group B (n = 32), 4mo after A; group C (n = 30), 3mo after B and group D (n = 28), 2mo after C. The animals grazed (in two sub-flocks) on irrigated tropical pastures managed in a rotational system (28 d of re-growth) at a mean stocking rate of 1,200 kg/ha/yr LW. The IF groups were reared in collective pens on a slatted floor (2 replicates of 7 or 8 kids each). They were fed the same stand of tropical grass (25% DM, 12% CP) as that of pasture that was cut daily and provided ad libitum. The ADG (-10%), the weights of omental fat (-60%) and fat in shoulder (-18%), the ultimate pH of carcass (-12%), the meat colour score (-24%), the ""parameter accounting for redness (12%) and the DM and lipid contents (-4%) were significantly lower (p<0.05) in PF than in IF, while the liver was heavier (+23%, p<0.05). Feeding conditions seemed to be similar, thus, differences could be related to gastrointestinal parasitism in the PF system and hypotheses are discussed. Increasing the fattening duration, resulted in significant difference (p<0.01) in many traits: the weights at slaughter and of carcass increased by 40% and 60% from groups A to D and consequently the weights of body compartments and carcass cuts (1.5 to 2.0 fold more). When the results were presented as percentage of empty body weight and carcass weight, these preliminary results (carcass weight 9kg and yield 53%, muscle proportion 70%) and qualitative parameters (low fat score 2/5, fat proportion 5%), seem to be a good incentive for the sector to develop a niche market to meet consumer lean meat expectations. The indoors system could be implemented where there was low availability of grazing areas or problems of dog attacks.

• Journal of Korean Library and Information Science Society
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• v.9
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• pp.63-83
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• 1982

Among many open libraries under the rule of the Japanese imperialism, only the railroad library as the character of special library under the control of the Japanese Government General is remarkable for having opened its facilities to outsiders as well as the interior users. This study tries a) To look into what were the colonial background, aim and motive of the establishment of the railroad library under the Japanese rule, b) To analyze its activities and the change of its organization, c) And to find out its vestiges an the effects which it has on our country's library circles. The following are the result: A. The railroad library under the rule of the Japanese imperialism functioned as a public library by the outside book's circulation rather than the interior using. B. The outsiders were qualified to use it only when they got the joint guarantee for the city resident, which means that the o n.0, pportunity of the circulation was not free for the Koreans rather than the Japanese. C. From the aspect of collections, technical books such as natural science, and reference ones tended to be collected, and their whole composition was focused on the materials for the Japan-Korea identification scheme and development of the national spirit as the Japanese empire's subjects. D. In the respect of its organization, all the clerical employees, as well as the chief librarian were composed of the Japanese. Although the Koreans were in principle prohibited from working there, a few of them were employed as guard or servant as the China-Japan War was close to the end. E. The area of the outside book's, circulation service was expanded throughout the whole region along the railroad connecting Pusan with Manchuria. Such a service activity which contained several meanings, was tried by means of culture's books, circuit's books, train's books, hotel's books, mind's development books and reader's reading books etc. F. Such matters as the limitation on book circulating and the quantity of circulation book, the paid circulation and the partial restriction on free circulation mean the wartime system under the rule of the Japanese imperialism and also a n.0, ppeared as a factor of hampering the Koreans from getting accustomed to using library, which has affected them until now. G. The noticeable thing in the service activity is shown in attempting the diversified and positive way of service like free circulation in order to solidify the attitude of the Koreans toward war by organizing mind's development books as well as culture's books with the China-Japan War. H. On the other hand, it can not be passed over that the diversified service activity of the railroad library played a role of bridge in turning of today's library circles of ours to the modernization.

• YAKHAK HOEJI
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• v.40 no.4
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• pp.428-437
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• 1996

The in vitro and in vivo antibacterial activities of a new fluoroquinolone, DWP20364(1-cyclopropyl-5-amino-6,8-difluoro-7-(2,7-diazabicyclo[3.3.0]oto-4-ene-7-yl)-1 ,4-di-hydro-4-oxoquinoline-3-carboxylic acid) were evaluated in comparison with those of ciprofloxacin(CPFX), sparfloxacin(SPFX) and ofloxacin(OFLX). DWP20364 was more potent than CPFX and OFLX against Staphylococcus spp., Streptococcus spp. and Enterococcus faecium MD8b and it was similarly or slightly less active than CPFX against Escherichia spp. and Pseudomonas spp.. For MRSA and OFLX resistant strains (Staphylococcus spp.(14),Enterococcus spp.(4), Acinetobacter spp.(2), Pseudomonas spp.(9), Klebsiella spp.(2) and Serratia spp.(6)),DWP20364(MICs for 90% of strains,0.025 and 12.5${\mu}$g/ml, respectively) was 4 to 32 folds more potent than SPFX and CPFX. The activity of DWP20364 decreased moderately in the presence of 5mM $Mg^{2+}$. However, various pHs and the concentrations of various serum had no effect on the activity of DWP20364. DWP20364 possessed a bacteriocidal effect at the 1MIC against gram positive and gram negative strains. The protective effect of DWP20364 against systemic infections in mice caused by S. aureus Smith or S. aureus L2379 was superior to that of CPFX and SPFX but it was less active than that of CPFX against infection by P. aeruginosa E-2.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.37-45
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• 1975

The present study was ,conducted to evaluate the effects of condensed phosphates on the refeezing damage of Alaska pollack muscle. The fillets were dipped in such solution as 5 and $10\%$ sodium polyphosphate, 1 and $5\%$ mixture of sodium polyphosphate and sodium pyrophosphate (1:1, w/w) for 1 and 5 minutes, respectively, before refreezing. And fillets were frozen at $27^{\circ}C\~28^{\circ}C$ and stored for 15 days at $-18^{\circ}\~-20^{\circ}$. The degree of denaturation was estimated by determining amounts of drip relased, content of total solids, nitrogen, and DNA in the drip an cooking-weight-loss. Phosphorus absorbed in the muscle was also determined. Phosphorus absorbed in the fillets treated with loft solution of sodium polyphosphate for 5 minutes amounted to 101 mg/100g muscle as $P_2O_5$. The absorption was dependent on tile concentration of treating solution rather than on the dipping time. The increase of phosphorus absorption seemed to affect to reduction of drip. Among the treating conditions, $10\%$, 5 minutes and $10\%$ 1 minute with sodium polyphosphate appeared most effective ones on drip reduction. The effect of $5\%$, minutes with the mixture of sodium polyphosphate and sodium pyrophosphate did not show so benefitable effect in refrozen fillets. As a tendency total solids, nitrogen, and DNA in tile drip varied proportionally to the amount of drip released. And the content of DNA was lower than the amount. Treatment, at higher the concentration and longer the dipping time, resulted in the lower cooking-weight-loss and the better quality on organoleptic test of thawed fillets.

• Natural Product Sciences
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• v.13 no.1
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• pp.33-39
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• 2007

Eleven polyhydroxyursane triterpenoids (PHUTs) were tested to determine their cytoprotective, immunosuppressive and anti-inflammatory effects. To compare the bioactivities of $19{\alpha}$-hydroxyursane-type triterpenoids {23-hydroxytormentic acid (6), its methyl ester (7), tormentic acid (8), niga-ichigoside $F_1$ (9),euscaphic acid (10) and kaji-ichigoside $F_1$ (11)} of the Rosaceae crude drugs (Rubi Fructus and Rosa rugosae Radix) with PHUTs possessing no $19{\alpha}-hydroxyl$ of Centella asiatica (Umbelliferae), the four PHUTs, asiaticoside (1), madecassoside (2), asiatic acid (3), and madecassic acid (4) were isolated from C. asiatica and 23-hydroxyursolic acid (5) from Cussonia bancoensis. Cytoprotective effects were assessed by measuring cell viabilities against cisplatin-induced cytotoxocity in $LLC-PK_1$, cells (proximal tubule, pig kidney) to determine whether these agents have protective effects against nephrotoxicity caused by cisplatin. The inhibitory effect of 11 PHUTS on nitric oxide (NO) and prostaglandin $E_2\;(PGE_2)$ were evaluated by measuring nitrite accumulation in lipopolysaccharide (LPS)-induced macrophage RAW 264.7 cells, and their anti-inflammatory effects were tested in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema model. Six MHUTs (compounds 1, 2, 4, 6, 10, and 11) exhibited higher cell viabilities during cisplatin-induced cytotoxicity testing even at a concentration of $200\;{\mu}g/ml$ than cisplatin only-treated group, suggesting that ese compounds have the potentcytoprotective efffcts. Compounds 1 and 3 of the C. asiatica and niga-ichigoside $F_1$ exhibited no inhibitory effect on NO and/or $PGE_2$ production whereas other PHUTs produced mild to significant NO and/or $PGE_2$ production.The four compounds (2, 5, 9, and 10) potently inhibited mouse ear edema induced by TPA whereas two compounds (1 and 3) had no activity in this test. These results suggest that many PHUTs are potentchemopreventives. Structure-activity relationship (SAR) was also discussed in each assay with regard to the significant role of OHs at the position of 2, 3, 6, 19, and 23 and to the glycoside linkage at the 28-carboxyl.

• 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.

• Journal of the Korean Vacuum Society
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• v.12 no.3
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• pp.168-173
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• 2003

Recently, according to the rapid progress in Flat-panel-display industry, there has been a growing interest in the poly-Si process. Compared with a-Si, poly-Si offers significantly high carrier mobility, so it has many advantages to high response rate in Thin Film Transistors (TFT's). We have investigated a new process for the high temperature Solid Phase Crystallization (SPC) of a-Si films without any damages on glass substrates using thin film heater. because the thin film heater annealing method is a very rapid thermal process, it has very low thermal budget compared to the conventional furnace annealing. therefore it has some characteristics such as selective area crystallization, high temperature annealing using glass substrates. A 500 $\AA$-thick a-Si film was crystallized by the heat transferred from the resistively heated thin film heaters through $SiO_2$ intermediate layer. a 1000 $\AA$-thick $TiSi_2$ thin film confined to have 15 $\textrm{mm}^{-1}$ length and various line width from 200 to 400 $\mu\textrm{m}$ was used as the thin film heater. By this method, we successfully crystallized 500 $\AA$-thick a-Si thin films at a high temperature estimated above $850^{\circ}C$ in a few seconds without any thermal deformation of g1ass substrates. These surprising results were due to the very small thermal budget of the thin film heaters and rapid thermal behavior such as fast heating and cooling. Moreover, we investigated the time dependency of the SPC of a-Si films by observing the crystallization phenomena at every 20 seconds during annealing process. We suggests the individual managements of nucleation and grain growth steps of poly-Si in SPC of a-Si with the precise control of annealing temperature. In conclusion, we show the SPC of a-Si by the thin film heaters and many advantages of the thin film heater annealing over other processes

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.96-96
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• 2018

금속재료 중 알루미늄(Al)은 일반적으로 많이 사용되는 철강재에 비해 그 비중이 약 $1/3(2.7g/cm^3)$인 경량이고 열전도율이 약 3배($196kcal/^{\circ}C$, $20^{\circ}C$)로 높은 특성 등을 갖고 있다. 또한 대량생산에 의한 경제성을 가지기 때문에 건축 구조재, 전기 및 가전 등 다양한 산업 분야에서 널리 사용되고 있다. 특히, 위와 같은 특성으로 인해 열교환기의 종류에서 응축기(Condenser) 및 증발기(Evaporator)는 알루미늄(Al)을 널리 사용하고 있다. 하지만 단일 응축기 부품에도 이종 알루미늄 소재가 사용됨에 따라 갈바닉 부식이 발생할 수 있다는 단점이 있다. 따라서 본 연구에서는 현재 상용되고 있는 열교환기 중 응축기에서의 이종 알루미늄 재료로 인해 나타나는 갈바닉 부식 특성을 관찰-분석-연구 하였다. 본 연구에 사용된 알루미늄 재료는 현재 응축기 재료 중에서 각각 Tube와 Fin으로 널리 상용되고 있는 Al 1100과 Al 3003을 사용하였다. 표면 모폴로지는 SEM을 통해 관찰하였고 EDS를 통해 조성원소를 분석하였다. 또한 내식성 평가를 위해 5% NaCl 환경에서의 SST(Salt spray test, 염수분무시험) 시험과 3% NaCl 용액 내 자연침지 시험 및 탈기된 3% NaCl 용액 내 전기화학적 동전위 양극 분극 시험을 진행하였으며 더불어 갈바닉 부식 시험에 따른 혼합 전위 측정 및 외관 관찰을 하였다. 각 재료는 실험에 대해 동일한 표면적을 노출시켜 시험하였다. 5% NaCl 환경에서의 염수분무 시험 결과 Fin(Al 3003)의 경우에는 Tube(Al 1100) 보다 빠른 부식거동을 보이며 국부적인 공식부식(Pitting corrosion)이 촉진되었다. Tube(Al 1100)의 경우에는 치밀한 Al2O3 형성과 부식에 따른 Al(OH)3를 생성함에 따라 Fin(Al 3003)에 비해 느린 부식거동을 보였다. 3% NaCl 용액 내 자연 침지 및 전위 측정 결과 초기 전위는 Fin(Al 3003, 약 -0.85V/SCE)이 Tube(Al 1100, 약 -1.05V/SCE)에 비해 더 높은 값을 가지며 약 72시간 이후 Tube(Al 1100) 시편이 더 안정적인 전위 값을 나타냈다. 이는 안정적인 Al(OH)3 피막 형성에 기인한 것으로 사료된다. 탈기된 3% NaCl 용액 내 전기화학적 동전위 양극 분극 시험 결과 Fin(Al 3003) 시편에서 더 귀한 부식 전위 값을 나타냈지만 부식 전류는 더 낮은 값을 나타냈다. 상기 시험 결과를 바탕으로 Fin-Tube 간 장기간 접촉 시에는 갈바닉 부식이 발생할 수 있을 것으로 사료된다. 갈바닉 부식 시험 결과 초기 혼합 전위는 약 -1.05 V/SCE를 나타냈으며 약 288시간 경과 후 약 -0.85 V/SCE 값을 나타냈다. 이는 자연 전위 측정 및 동전위 양극 분극 시험에서의 부식 전위 값에서 알 수 있듯이 더 비한 전위인 Tube(Al 1100) 시편이 Fin(Al 3003) 시편에 대해 희생양극적(Sacrificial anode)인 역할을 한 것을 확인할 수 있었다. 또한 갈바닉 부식 전위 측정 간 외관 관찰에서도 Tube(Al 1100) 시편은 빠르게 흑변 하는 것을 확인할 수 있었으며 Fin(Al 3003) 시편은 침지 300시간 이후에도 초기와 유사한 표면 상태 및 광택을 유지하였다. 이상의 SST 시험, 자연 침지 시험, 전기화학적 양극 분극 시험 및 갈바닉 부식 시험 결과를 바탕으로 단일 부품 내 이종 알루미늄 소재 간 접촉 및 그에 따른 갈바닉 부식 발생을 확인할 수 있었다. 따라서 동종 성분이라고 할지라도 단일 부품 제작 시에는 그 사용 환경에 따라 이종 금속 재료의 사용에 대한 재고가 필요할 것으로 사료된다.

• Journal of Biosystems Engineering
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• v.1 no.1
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• pp.55-55
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• 1976

An experimental work was conducted to develop an optimum operating system of various hay drying systems ; sun-drying with long hay, sun-drying after chopping, sun-drying after crushing, heated air drying after chopping using batch-type dryer and heated air drying after crushing using tunnel-type dryer. Seombody having 60 cm long and initial moisture content of approximately 79 % in wet basis was used for the experiment. The criteria selected for determining the optimum operating condition were the drying performance rate, the production cost and quality of dried matter of each drying systems. The result of this study are summarized as follows : 1. Drying characteristics of leaves of long stem hay, chopped seombody and crushed one were obtained by maintaining the oven temperature at 70 degrees centigrade. The required drying times for various samples to approximately 15% moisture content in wet basis were about 50 min .for leaves ; 160 min. for crushed hay ; 250 min. for chopped hay ; 340min. for ling hay and more than 360 min .for stems. The drying time of crushed hay was required about 50 % of that for the uncrushed long hay. Such a significant difference of drying of time between the leaf and long stem may indicate that an effective drying of seombody may not be achieved unless any kind of special process treatment for the whole hay is undertaken. 2. In each individual drying system, the following conclusions were drawn: a. After 8 days sun-drying on concrete floor under good days with average tempe?rature at $256{\circ}C$ and relative humidity at 55% at 2 P.M., the moisture content of long hay was still above 25 5'~ and the leaf loss during drying caused by wind and rough handling was more than 50 ~G. b. It was possible to dry the chopped seombody by sun-drying down to about 10 % moisture content within 5 days, however, a stock of heat and discolouration phenomena were observed during the drying, which may be due to the increased deposit-density by chopping, resulting in lowering the quality of the dried product. c. Sun-drying for the crushed material by hay-conditioner was required about 4 days to reduce the moisture content to about 10 %, keeping the quality of dried product at good grade. o. The optimum deposit-depth of the chopped seombody in the batch-type dryer used was about 28cm with about 42kg/hr of drying performance rate. However, it was necessary to overturn the materials between the upper and lower layers in order to obtain a good quality of dried product. d. The drying performance rate by the tunnel-type drier was highest among those of drying systems tested, giving the rate of approximately 400kg/day. 3. On reviewing the individual drying system for seombody, it was possible to draw conclusion that the best system was tunnel drying with the crushed seombody as far as the performance rate was concerned. However, the methods gives the highest operational cost. The system for the lowest operational cost with good quality of dried product was the sun-drying with the crushed material. Accordingly, it may be recommended that the system of sun-drying for the crushed seombody may be the most feasible system presently applicable to farm-level operation.