• Journal of Pharmaceutical Investigation
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• v.34 no.5
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• pp.369-377
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• 2004

The objective of this study was to investigate the patterns of protein leaching to an external phase during an ethyl acetate-based, double emulsion microencapsulation process. An aqueous protein solution (lactoglobulin, lysozyme, or ribonuclease; $W_1$) was emulsified in ethyl acetate containing poly-d,l-lactide-co-glycolide 75:25. The $W_1/O$ emulsion was transferred to a 0.5% polyvinyl alcohol solution saturated with ethyl acetate $(W_2)$. After the double emulsion was stirred for 5, 15, 30, or 45 min, additional 0.5% polyvinyl alcohol $(W_3)$ was quickly added into the emulsion. This so-called quenching step helped convert emulsion microdroplets into microspheres. After 2-hr stirring, microspheres were collected and dried. The degree of protein leaching to $W_2$ and/or $W_3$ phase was monitored during the microencapsulation process. In a separate, comparative experiment, the profile of protein leaching to an external phase was investigated during the conventional methylene chloride-based microencapsulation process. When ethyl acetate was used as a dispersed solvent, proteins continued diffusing to the $W_2$ phase, as stirring went on. Therefore, the timing of ethyl acetate quenching played an important role in determining the degree of protein microencapsulation efficiency. For example, when quenching was peformed after 5-min stirring of the primary $W_1/O$ emulsion, the encapsulation efficiencies of lactoglobulin and ribonuclease were $55.1{\pm}4.2\;and\;45.3{\pm}7.6%$, respectively. In contrast, when quenching was carried out in 45 min, their respective encapsulation efficiencies were $39.6{\pm}3.2\;and\;29.9{\pm}11.2%$. By sharp contrast, different results were attained with the methylene-chloride based process: up to 2 hr-stirring of the primary and double emulsions, less than 5% of a protein appeared in $W_2$. Afterwards, it started to partition from $W_1\;to\;W_2/W_3$, and such a tendency was affected by the amount of PLGA75:25 used to make microspheres. Different solvent properties (e.g., water miscibility) and their effect on microsphere hardening were to be held answerable for such marked differences observed with the two microencapsulation processes.

• Journal of Nutrition and Health
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• v.43 no.1
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• pp.86-96
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• 2010

This study was conducted to investigate the effects of residence types ((1) parent house, (2) dormitory or boarding home, (3) boarding home w/o food) on the dietary habits and health status of college women (20-23 y). Overall, 46.1% of college women reported that they were economically middle class and spent 200,000-390,000 won. Additionally, 17.4% of college women considered themselves healthy, while 33.8% reported that they were not healthy. Furthermore, 32.0% of college women had experience to control their weight and 39.8% reported that they exercised to control their weight. There were no significant differences in the height and weight of the subjects according to residential type, but the amount of skeletal muscles mass ($21.0\;{\pm}\;2.6\;kg$) of the subjects that lived in dormitory or boarding home was significantly higher (p < 0.05) than that of women who lived at home. Additionally, 30.8% of students that lived in private residences, 25.0% of students that dwelled in dormitory or boarding homes and 27.7% of students that boarding home w/o food had three regular meals every day (p < 0.05). It has been reported that 18.3% of college students eat processed and instant foods due to their convenience. In the present study, intakes of energy, protein, fat, vitamin A, vitamin $B_1$, vitamin $B_2$, vitamin $B_6$, niacin, vitamin C, vitamin E and folic acid for the subjects who lived in dormitory or boarding homes was significantly higher than those of students who lived in private residences (p < 0.05). Additionally, intakes of iron, calcium, and zinc were lower in the subjects that boarding home w/o food (p < 0.05). Finally, the blood glucose level was $84.7\;{\pm}\;13.0\;mg/dL$, and differed significantly by residential types (p < 0.05); however, the average glucose levels of all subjects were within the normal range (90-110 mg/dL).

• Korean Journal of Poultry Science
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• v.34 no.3
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• pp.187-196
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• 2007

This experiment was conducted to investigate the effect of dietary single or mixed supplementation of plant extract, fermented medicinal plants and Lactobacillus on performance, nutrient availability, blood characteristics, cecal microflora and intestinal digestive enzymes activity in broiler chickens and to prove the possibility of plant derived compounds and Lactobacillus as an antibiotic growth promoter alternative. A total of eight hundred forty, 1-d-old male broiler chicks (Ross strain) were randomly divided into 7 groups with 4 replicates of 30 birds each. The treatments were NC (antibiotic-free diet), PC (basal diet with 0.05% antibiotics and 0.03% anticoccidials), PE (basal diet with 0.1% plant extract), FMP (basal diet with 0.1% fermented medicinal plants), LB (basal diet with 0.1% probiotics), PE+LB (basal diet with 0.1% plant extract and 0.1% probiotics) and FMP+LB (basal diet with 0.1% fermented medicinal plants and 0.1% probiotics). The final body weight, body weight gain and feed conversion rate in all treated groups tended to be improved or significantly improved as compared to those of NC (P<0.05). PE was significantly high in the final body weight, body weight gain of all treated groups (P<0.05). But the growth performance was significantly lower in all treated groups except PE than PC (P<0.05). No synergic effect in growth performance was found when plant extracts and Lactobacillus were mixed and fed to broilers. The ratio of albumin to globulin was significantly lower in all groups than NC (P<0.05). And the stress indicator (lymphocyte/heterophil ratio) of NC was significantly reduced than other treatments (P<0.05). No significant differences were observed on the numbers of cecal microbes and Lactobacillus. The number of cecal E. coli and Salmonella in FMP and LB were significantly reduced (P<0.05). The activity of intestinal digestive enzymes except to sucrase of treated groups significantly decreased compare to those of controls (P<0.05). These results suggest the possibility that plant extracts and Lactobacillus could be used as the alternative of antibiotic growth promoters by improving the performance of broiler chicks.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.99-100
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• 2004

AMBIDEXTER-NEC의 천이노심은 $^{Nat}Th$과 $^{Nat}U$의 주입만으로 전 출력의 Break-even 노심에 도달하기위한 중간 단계이다. 선행연구에서 수행한 전 출력노심인 평형노심의 핵종수밀도에 도달하기 위해서 평형노심에서의 기저물질, 잠재핵분열성물질, 핵분열물질의 수밀도를 각 SEU-기반, Pu-기반, ADS-기반에서 그대로 유지하여 초기노심을 구성하였다. 또 각 시나리오에 대해 최대첨두출력과 원자로의 안전성을 고려해 Excess Reactivity를 5mk 내에서 초기노심을 결정하였다. 각 노심은 주 핵분열성물질 $^{235}U$, $^{239}Pu$ 및 $^{233}U$의 핵반응단면적 특성에 따라 평균 전환율이 각각 0.95, 0.83 및 1 .21 로서 핵연료물질의 적절한 선택만으로도 전환로, 연소로 및 증식로로 설계할 수 있음을 보여준다. 이러한 $Th/^{233}U$, U/Pu 핵연료주기를 사용하는 AMBIDEXTER-NEC 용융염핵연료 원자로의 초기노심에서 시작한 천이노심은 평형노심에장전할 충분한 $^{233}U$ 양을 확보해야 하므로 천이노심의 목표는 평형노심 $^{233}U$의 요구량에 최소한의 기간에 가장 적은 외부주입을 통해 도달하는 것이다. 천이노심에서 임계가 유지되는 AMBIDEXTER-NEC 원자로시스템의 3군 핵종변환 코드인 HELIOS-SQUID-AMBIBURN 체제를 개발하였고 그림 1.에 나타내었다. 이 알고리즘은 각 초기노심 중원소의 미시단면적, 중원소를 제외한 원소들의 거시단면적, 임계도를 만족하는 중성자속 및 외부주입율을 계산하여 SQUID 및 AMBIBURN 입력자료를 제공한다. 또한 일정시간 중원소의 핵종농도, 외부주입율과 중성자속이 일정하다는 가정 하 에 반복수행 하고 SEU-기반과 Pu-기반의 경우에는 각각 핵변환을 거쳐 재순환되는 $^{233}U$ 및 $^{239}Pu$의 양을 바로 주입하는 최대재순환 경우와 평형노심 요구 장전량에 이를 때까지 시설 내 저장하는 최소재순환 경우로 상황을 모사하였다. 그림 2 는 각 시나리오별 초기노심에서부터 200FPD까지 단위 용융염 체적당 $^{233}U$의 수밀도 시간변화를 나타낸 것이다. 그림을 보면 50일 이후부터는 수밀도의 변화가 일정한 기울기를 보이고 있고 재처리공정에서 $^{233}Pa$를 분리하는 최소재순환의 경우에는 최대재순환보다 2-3%정도에 지나지않아 그림에서 나타내지않았다. SEU-기반 및 Pu-기반에서 $^{233}U$의 증가율이 각각 2.54E+13, 2.81E+13 #/cc/d 로 Pu 기반이 조금 더 큰 증가율을 나타내고 있지만 평형노심 농도 1.04E+20 #/cc/d 에 도달하기 위해서는 두 경우 모두 매우 긴 시간이 걸릴 것을 예상할 수 있다. 요컨대 250MWth AMBIDEXTER-NEC가 평형노심을 이루기 위해 필요로 하는 $^{233}U$을 생산하는데 제안한 SEU-기반, Pu-기반 시나리오는 천이노심주기기간이 전형적인 원자로 수명 3-40년 보다 매우 큰 것으로 나타났다. 따라서 장전될 $^{233}U$의 확보를 위한 최적옵션은 초기노심부터 ADS와 같은 외부생산시설로부터 전량을 공급 받아 운전하는 것이라 판단된다.

• Advances in pediatric surgery
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• v.3 no.1
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• pp.61-67
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• 1997

To understand the current status of pediatric surgical practice of the members of the Korean Association of Pediatric Surgeons, a survey of the practice of the 31 members in both 1994 and 1995. Twenty five members(80%) representing 20 hospitals responded. An average of four hundred and seventy four cases pediatric surgical operations were performed at individual institution in 1995 with 40 newborn cases. Eighteen members(72%) are currently working at university hospital. Fourteen institutions(70%) are currently classified as tertiary by the health insurance agency. The majority(15 to 60%) of members are working in the metropolitan Seoul area, while five in Taegu area. Sixteen members reported having the title of department head/director. Four members reported occasional non-pediatric surgical practice. Nine members out of 20 reported having independent pediatric surgical out-patient clinic before the establishment of the association(1985). Eight out of 15 members reported being appointed chief of pediatric surgery before 1985. In 20 institutions, 34 full time physicians(27 members, reportedly) are working in pediatric surgery. In regarding to pediatric surgical training, 16 members(64%) received an average of 16 months of training abroad, 5 members trained at home and abroad, and 4 from only at home. There are no differences in length of training periods in these groups. Twenty one members received their basic pediatric surgical training before 1985, the year of inauguration of the association. Twelve members received post-pediatric surgery refresher courses averaging 11 months' duration, after 2-11 years. Thirteen participants of this study belongs to the founding members of the association.

• Journal of the Korean Electrochemical Society
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• v.1 no.1
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• pp.33-39
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• 1998

To AC impedance study was performed in this study on the interfacial reaction between organic electrolyte and amorphous tungsten oxides thin film, cathodically coloring oxide, prepared by e-beam evaporation method in the 1 M $LiClO_4/PC$ organic solution. The electrochemical reactions at the interface were analyzed by the transient method and the complex impedance spectroscopy. The impedance spectrums showed that the electro-chemical intercalation of lithium cations was consisted of the following three steps; the first step, the charge transfer reaction of lithium cation at the interface between amorphous tungsten oxides thin film and the organic electrolyte, the second step, the adsorption of lithium atom on the surface of amorphous tungsten oxides thin film, and then the third step, the absorption and the diffusion of lithium atom into amorphous tungsten oxides thin layer. The bleaching and the coloring characteristics of amorphous tungsten oxides thin film were explained in terms of thermodynamic and kinetic variables, the simulated $R_{ct},\;C_{dl},\;D$ and $\sigma_{Li}$ by CNLS fitting method. Especially it was found that the limiting values of electrochromic reaction were the molar ratio of lithium, y=0.167 and the electrode potential, E=2.245 V (vs. Li).

• Advances in pediatric surgery
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• v.2 no.1
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• pp.33-41
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• 1996

This report present the result of the national survey of pediatric surgeons' preferences on diagnosis and treatment of Hirschsprung's disease(HD) carried out in 1993. The questionnaires were sent to twenty-seven members of the Korean Association of Pediatric Surgeons (KAPS) working in twenty-four institutions. The questionnaires were designed to determine the individual surgeon's preference for the methods of diagnosis and treatment of the disease. Twenty-three pediatric surgeons from twenty institutions returned completed forms. The total number of patients diagnosed with HD in 1992 was 190 in this group. The estimated incidence of HD was 1/3,900. The most important symptom was delayed meconium passing and the most preferred diagnostic procedure was barium study. Anorectal manometric examination was carried out by 13 pediatric surgeons and 19 confirmed the diagnosis before operation by rectal biopsy, 12 with full-thickness biopsy and 7 with suction. Frozen section biopsy during operation was done by 22 surgeons. Eight surgeons did one stage operation if the age of the patient is suitable. Definitive operation was usually done at the age of 6 to 11 months. The most preferred operation was Duhamel procedure done by 19. Enterocolitis was the most serious complication of HD. Most of patients had normal continence within 6 to 12 months after operation. The follow-up period was less than 6 years in 16 surgeons. The results were presented at the 9th annual meeting of KAPS in June of 1993. This is the first national survey of HD and it can provide guidelines of diagnosis and treatment of Hirschprung's disease even though it is not a detailed study of patient data.

• Journal of the Korean earth science society
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• v.21 no.4
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• pp.437-448
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• 2000

The Middle Carboniferous Gabsan Formation is distributed in the Cheongrim area of southern Yeongwol and the Mt. Gachang area of Chungbuk Province. This study was carried out to investigate the lithological characters and geochemical composition of the limestones and to find out controlling structures of the limestones of the formation. The limestones of the Gabsan Formation are characterized by the light gray to light brown in color and fine and dense textures. The limestone grains are composed of crinoid fragments, small foraminfers, fusulinids, gastropods, ostracods, etc. Due to the recrystallization, some limestones consist of fine crystalline calcites. The chemical analysis of limestones of the formation was conducted to find out the contents of CaO, MgO, Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$. The content of CaO ranges from 49.78-60.63% and the content of MgO ranges from 0.74 to 4.63% The contents of Al$_2$O$_3$ and Fe$_2$O$_3$ are 0.02-0.55% and 0.02${\sim}$0.84% , respectively. The content of SiO$_2$ varies from 1.55 to 4.80%, but some samples contain more than 6.0%. The limestones of the formation can be grouped into two according to the CaO content: One is a group of which CaO content ranges from 49.78 to 56.26% and the other is a group of which CaO content varies from 59.36 to 60.38%. In the first group, the contents of Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$ range very irregularly according to the CaO content. In the second group, the values of MgO, Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$ are nearly same. Detailed structural analysis of mesoscopic structures and microstructures indicates the five phase of deformation in the study area. The first phase of deformation(D$_1$) is characterized by regional scale isoclinal folds, and bedding parallel S$_1$ axial plane foliation which is locally developed in the mudstone and sandstone. Based on the observations of microstructures, S$_1$ foliations appear to be developed by grain preferred orientation accompanying pressure-solution. During second phase of deformation, outcrop scale E-W trending folds with associated foliations and lineations are developed. Microstructural observations indicate that crenulation foliations were formed by pressure-solution, grain boundary sliding and grain rotation. NNW and SSE trending outcrop scale folds, axial plane foliations, crenulation foliations, crenulation lineations, intersection lineations are developed during the third phase of deformation. On the microscale F$_3$ fold, axial plane foliations which are formed by pressure solution are well developed. Fourth phase of deformation is characterized by map scale NNW trending folds. The pre-existing planar and linear structures are reoriented by F$_4$ folds. Fifth phase of deformation developed joints and faults. The distribution pattern of the limestones is mostly controlled by F$_1$ and F$_4$ folds.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.319-329
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• 1996

During the monsoon in Bangladesh, the possibility of preserving wet ($700g\;H_2O$) straw by urea (50 g/kg straw DM) with or without polythene cover has been studied. The quality of preserved straw (PS) in terms of colour, smell and fungal infestation were recorded. Nutritive value of the PS was compared to that of a dry straw (DS) in two separate feeding trials on growing bulls (about 290 kg) without (Expt. 1) or with (Expt. 2) concentrate supplements. Over 96% of the wet straw was excellently preserved for over 5 months when covered with polythene in horizontal heaps (of appx. 4 tons). Whereas only 33% of the straw was well preserved in the uncovered (dome shaped) heaps (of approximately 9.5 tons). Each ton of wet straw costed Tk. 1413 and its preservation cost incurred Tk. 345. Urea preservation increased the crude protein content (95 vs. 50 g/kg), dry matter (DM) degradability at all (8, 16, 24, 48, 72 and 96) hours of incubation and at 48 hours, DM degradability (%) were 45 and 25 respetively for the PS and the DS. When fed alone, DM intake (75 vs. $106g/kg\;W^{0.75}/d$), total microbial N yield (27 vs. 54 g/d) and growth rate (-379 vs. 283 g/d) were higher (p < 0.01) in the PS than the DS. Supplementation of concentrate reduced the straw DM intake both in the DS ($51g/kg\;W^{0.75}/d$) and the PS ($958g/kg\;W^{0.75}/d$), but the substitution rate (SR%) was higher in the PS (42) than the DS (27). Higher substitution rate was probably responsible for the reduction in the differences between the DS and PS in their nutrient digestibilities, total microbial N yield (62 vs. 64 g/d) and growth rate(669 vs 339 g/d) when supplemented with concentrate. On 28th day of Expt. 2, feeding PS from one of the polythene covered heaps resulted nervous disorder due to unknown reason(s). Further studies on the effect of size and shape of heap on the preservation quality need to be determined.

• Journal of Animal Environmental Science
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• v.17 no.3
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• pp.181-188
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• 2011

With an increasing livestock population, animal manure production has been steadily increasing in Korea. This trend has forced farmers to spend more money for animal manure treatment in their farm. Therefore, research utilizing animal manure as a renewable resources has become increasingly important. The purpose of this study was to develop a stable advanced wastewater treatment system can be applied to conventional animal wastewater treatment processes and evaluate its contribution to reduce effluent discharge volume by recycling as flushing water. AOP (advanced oxidation process) process improved wastewater treatment efficiency in terms of color, suspended solids (SS) and chemical oxygen demand (COD). Due to the addition of Hydrogen peroxide ($H_2O_2$), pathogens, Salmonella and E. coli, reduction was accomplished. To enhance ozone treatment effect, three levels of ozone test on secondary effluent of pig slurry purification system were conducted. At the level of 5 g/hr, 6.7 g/hr and 8.4 g/hr color of secondary effluent of pig slurry purification system were decreased from 2,433 to 2,199, 2,433 to 1,980 and 2,433 to 243, respectively.