• Macromolecular Research
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• 제9권2호
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• pp.122-128
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• 2001

Monodisperse composite latex particles with size of ca. 300 nm, which consist ofn-butyl acrylate as a soft phase and methyl methacrylate as a hard phase with different morphology, were synthesized by seeded multi-stage emulsion polymerization. Three types of composite latex particles including random-, core/shell-, and gradient-type particles were obtained by using different monomer feeding methods during semi-batch emulsion polymerization. Effect of poly(butyl acrylate)-poly(methyl methacrylate) rubber particle morphology on the mechanical and rheological properties of rubber toughened poly(methyl methacrylate) was investigated. Among three different rubber particles, the gradient-type rubber particle showed better toughening effect than others. No significant variation of rheological property of poly(methyl methacrylate)/rubber blends was observed for the different rubber particle morphology.

• 환경생물
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• 제20권2호
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• pp.180-188
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• 2002

부정형성게류인 구멍연잎성게는 제주도 연안에 널리 분포하고 있음에도 불구하고 생태학적 연구들이 미비한 실정이다. 이 연구는 구멍연잎성게의 행동학적 연구로서 먹이섭취, 서식밀도 및 이동에 대한 기초자료로서 시료는 제주도의 북동쪽에 위치한 함덕에서 SCUBA를 통하여 채집 및 현장에서 직접 관찰하였다. 장내용물 관찰 결과, 장내 퇴적물 입자의 평균 입도조성은 $77.6\pm{22.2}\mu{m}$였다. 장 내용물은 유공충, 저서성 요각류, 선충류, 규조류, 알, 해조류이 파편, 골편 등의 동식물 플랑크톤으로 구성되었다. 구멍연잎성게의 서식밀도는 $1m^2$ 당 0.4 개체이며, 분포패턴은 임의분포(random distribution)에 기초하는 것으로 판단되었다$(\chi^2=85.16,\;p>0.05)$. 구멍연잎성게의 이동거리는 여름철인 1998년 8월에 6.2-64.8cm $hr^{-1}(mean=25.0\pm{13.9)}$이었고, 5월에는 $2.0-43.0cm\;hr^{-1}(mean=17.7\pm{10.7)}$로 8월에 다소 높게 나타났다. 여름기간 중 관찰된 비교적 빠른 이동속도는 먹이 섭이 활동과 관련된 것으로 추정되었다.

• 한국가금학회지
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• 제45권2호
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• pp.81-88
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• 2018

본 연구에서는 농산부산물의 사료첨가 급여가 육계의 생산성과 혈액성상에 미치는 효과를 메타분석이라는 통계적 방법을 이용하여 조사하였다. 본 분석에 사용된 연구논문들은 모두 대한민국에 소재한 일반 상업 육계농가에서 사양시험을 수행하였고, 농산부산물의 사료첨가 급여 효과를 조사하였다. 총 11개의 연구논문에서 32개의 실험들을 메타분석에 이용하였다. 사양 단계는 총 사육일수를 기준으로 두 단계로 구분하였고, 생산성으로는 체중, 증체량, 사료섭취량 그리고 사료요구율을 평가하였다. 그리고 도체중, 도체율, 간장 및 비장 무게에 대한 효과를 평가하였다. 혈액성상으로는 혈중 포도당, 콜레스테롤, 중성지방, 고밀도지방단백 및 저밀도 지방단백함량에 대한 효과를 조사하였다. 농산부산물의 사료첨가 급여는 육계의 출하체중을 유의적으로 증가시키는 결과를 나타내었다. 사료요구율도 농산부산물을 사료첨가하여 급여한 처리구에서 유의적으로 낮게 나타났다. 즉, 농산부산물의 사료첨가급여는 육계 생산성을 개선할 수 있는 가능성이 존재함을 확인할 수 있었다. 도체중, 도체율, 간장 및 비장 무게에서는 유의적인 처리효과를 관찰할 수 없었으나, 복강지방은 농산부산물 급여 처리에 의해 유의적으로 감소하는 것을 확인하였다. 혈액성상에 있어서는 총 콜레스테롤 함량 및 중성지방 수치가 처리효과에 의해 유의적으로 감소하였고, 고밀도지방단백은 유의적으로 증가하였다. 일련의 결과를 통하여 농산부산물의 사료첨가 급여는 육계의 혈액성상 개선과 복강내 지방 침착 억제를 통한 생산성 개선의 효과를 갖는 것을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제9권4호
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• pp.389-396
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• 1996

In the first of two experiments, liveweight gain responses and carcass characteristics were investigated using two breeds of growing male goats, local (Dhofari) and exotic (Cashmere), fed on a whole pelleted-high fiber date by-products' based diet at 32.5% level (As-fed) supplemented with 12% fish (sardine), (HF-Fish) and a commercial concentrate diet (conc.). The (HF-Fish) diet was formulated to be iso-nitrogenous to the (conc.) diet, supplying 14% CP (DM-basis). Both diets together with Rhodes grass hay (Chloris Guyana) were fed ad libitum. The experimental design was a complete random arranged in a $2{\times}2$ factorial with breeds and diets as the main factors, using six animals per treatment. The experiment lasted for 84 days and goats were penned individually. At the end of the feeding trial, three animals from each treatment group were slaughtered for carcass evaluation. In experiment 2, diets' digestibility and N-balance were determined using 3 sheep per diet. The (HF-Fish) diet significantly(p < 0.05) improved liveweight gain. There was also a significant difference(p < 0.01) between breeds, with Cashmere gaining more than local goats. Feed conversion efficiency, dressing percent and longissimus dorsi area were not significantly affected by diet or breed(p > 0.05). Digestibility of the proximate components and N-balance for both diets were similar and not significantly different(p > 0.05). Fish supplementation greatly improved the digestibility of CF, ADF, NDF, cellulose and hemicellulose. Meat production ost was decreased by 31% due to feeding of the (HF-Fish) diet.

• 보건교육건강증진학회지
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• 제17권1호
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• pp.155-170
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• 2000

This study was aimed at preparing basic data required for establishment of a cancer screening program by examining the status of cancer screenings performed by women in a city and the factors that had an influence on cervical and breast cancers screening behavior of women. In order to find out the status of cervical and breast cancers screening and the factors having an influence on cervical and breast cancers screening behavior, 1,113 women were selected as study area and subjects by a random cluster sampling method, and the subjects were answered by questionnaires. The major results were as follows: 1. In the cases of the breast and the cervical cancers, 16.7% and 55.7% of the subjects turned out to have had one or more screenings respectively in their life-time. Also the rate of screening group of cervical and breast cancers was 16.7%, the rate of screening group of only cervical cancer was 38.9%, and the rate of non-screening group was 44.4%. 2. As to the screening pattern of cervical and breast cancer, there were significantly for age, income, occupation, married status, spouse, the factors associated with health promotion (doctor visiting, exercising), married age, number of children, and breast feeding(p〈0.05). 3. The factors associated with screening behaviors for cervical and breast cancers were age, income, occupation, married status, doctor visiting, exercising, married age, number of children, and breast feeding(p〈0.05). Based on the above-mentioned results obtained by this study, it was anticipated that this study may be playa vital role as basic data for the development and execution of cervical and breast cancers screening program for women in a community. And the analysis, done on the basis of the status of the cancer screening, of the influence factors on cervical and breast cancers screening behavior showed that for the development of a cancer screening program, the factors like age, social-economic class, married status, health promotion behavior, and reproductive characteristics should be considered.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1239-1244
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• 2000

In order to investigate the effect of incorporation of thermally processed cereal (maize) grain and differently degradable protein sources in the calf starter, twenty four newly born crossbred $(Bos\;taurus{\times}Bos\;indicus)$ calves were assigned at random to six diets in a $3{\times}2$ factorial design involving three protein sources viz. groundnut meal (GN), cottonseed meal (CS) and meat and bone meal (MB), each along with two differently processed grain, namely ground raw (R) and pressure cooked (P) maize. The corresponding calf starters with green oats (Avena sativa) were given free-choice from 14 d onwards till the end of the 90 d experimental feeding. A restricted milk diet was fed till the age of weaning at 60 d. Total DM intake was not affected by cereal or protein sources. However, daily intake of DM (59.23 vs 66.45 g) and CP (12.38 vs 14.10 g) per kg $W^{0.75}$ was reduced (p<0.05) due to cereal processing. Better (p<0.05) feed and protein efficiencies after weaning and during entire period in calves fed processed maize resulted in a trend of higher $(p{\leq}092)$ growth rate especially when GN was the source of protein. In comparison among protein sources, calves fed MB diets tended to grow faster $(p{\leq}098)$ concurrent with a higher CP intake before weaning. It is thus evident that thermal processing of maize in the calf starter seems to improve calf performance. Moreover, results indicated that feeding of protein and starch sources of matching ruminal degradability may prove beneficial for early growth of crossbred calves.

• Clinical and Experimental Pediatrics
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• 제64권3호
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• pp.130-135
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• 2021

Background: The clinical significance of lip-tie, or a tethered maxillary frenulum, remains under debate. Clinicians and parents are often perplexed when deciding whether procedures available to relieve a seemingly tight or severe maxillary frenulum are needed. Purpose: No previous studies have assessed the consequences of not subjecting a tethered maxillary frenulum in newborns to surgical intervention. This study aimed to contribute the first prospective trial on this topic with a relatively extended follow-up of these newborn infants. Methods: This prospective observational questionnaire-based cohort trial was performed in a community setting and aimed to determine whether lip-tie is associated with an increased likelihood of eventual feeding or oral disorders. Results: The convenience sample comprised of 61 consecutively arriving infants with concomitant tethered frenula who were treated at the clinic for various reasons. This cohort was compared with a random sample of 66 age-matched children for a mean follow-up period of 6.42 years. Infants undergoing oropharyngeal procedures were excluded. Awareness of a deviation in oral structures was reported by 18% of the study group versus 0% of the controls. Mothers participating in the study group (24.6%) less frequently recalled painful nipples or discomfort during breastfeeding than those in the control group (47.0%) (P<0.01). There were no intergroup differences in other types of feeding difficulty, dental hygiene, pronunciation, or speech development. Conclusion: Our findings suggest that a tethered labial frenulum is not associated with an increase in breastfeeding disturbances or oral disorders. These data encourage clinicians to question the need to intervene in cases of tethered maxillary frenula.

• Animal Bioscience
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• 제35권10호
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• pp.1524-1534
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• 2022

Objective: The objective was to test if creep feeding (CF) improves the average daily gain (ADG) and weaning weight of calves submitted to temporary weaning (TW) and if the combination of CF and TW improves conception and pregnancy rates of cows. Methods: Primiparous (n = 74) and primiparous and multiparous (n = 104) cows grazing native grasslands were used in experiment 1 and 2; respectively. The experimental design was in plots divided into complete random blocks with two replications. The CF was the big plot and TW the small plot, thus four experimental groups were formed: i) -CF-TW (n = 21 and 27); ii) -CF+TW (n = 16 and 24); iii) +CF-TW (n = 20 and 26); iv) +CF+TW (n = 17 and 27) with cow-calf pairs for experiments 1 and 2; respectively. Nose plate application for TW had a duration of 14 and 15 days for experiment 1 and 2: respectively. In experiment 1, calves were fed at 1% of live weight for 112 days using a commercial supplement with 18.4% crude protein. In experiment 2, the supplementation lasted 98 days, and was carried out with corn dried distillers grains with soluble (DDGS) at 40% of the potential intake on a daily basis. Results: The TW reduced ADG during the TW period and the following 14 days, but the negative effect of TW was maintained until the final weaning only in experiment 2. The CF increased ADG during TW period in both experiments. The TW promoted an earlier conception of the dams (12 days in -CF treatment and 19 days in +CF treatment, p<0.01) and CF increased pregnancy rate in experiment 1, being the effects not consistent between experiments. Conclusion: The CF consistently promoted an increase in ADG during the period of TW and increased final weaning weight of calves, therefore it is economically viable.

• 한국기계가공학회지
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• 제21권4호
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• pp.91-99
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• 2022

By applying METHOD 514.8 of the US military standard MIL-STD-810H, vibration analysis of the winding core automatic feeding device was performed during vehicle transportation. The contact point between the LM guide and main support frame was weak in the vertical axis, transverse axis, and longitudinal axis during the transportation of the automatic winding core feeder vehicle, and the maximum equivalent stress was 236.31 MPa in the longitudinal axis. When random vibration was applied, the safety margin in the longitudinal direction was 0.26, indicating low safety. The safety margin was changed by increasing the damage factor to 0.1. Finally, the safety margin was improved to 3.48 to secure safety. Resonance occurred with a Q factor of 9.34 in the harmonic response to which the RMS value of the ASD data was input, and the vertical axis safety margin was derived as 0.16. When the damping factor was 0.15, the Q factor was 3.37, and resonance was avoided with a safety margin of 6.62.

• 농업과학연구
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• 제45권1호
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• pp.84-93
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• 2018

This study was conducted to develop a pasture feeding program for reducing the Hanwoo feeding cost. Italian ryegrass (IRG) is a major plant which is abundantly produced in the southern area of South Korea. Locally produced Italian ryegrass has a 30 - 50% reduced pasture cost compared to imported pasture grasses. We hypothesized that Italian ryegrass feed could reduce the feeding cost but not change the physiological characteristics of the Hanwoo steers in the feedlot. Four treatments (Control, short fed IRG silage, long fed IRG silage, and IRG hay) in a completely random design were used to feed 27 Hanwoo steers. Three or four steers were fed in the same pen, and 8 pens were used for the treatments. Blood was drawn from each steer on the first week of every month from 11 to 30 months. Overall, the average daily gain and feed efficiency were not different among the treatments (p < 0.05) except for the final fattening diets (p < 0.05). The long fed IRG silage group had a low ADG compared to the other groups (p < 0.05). The serum non-esterified fatty acid and glucose concentrations were reduced during the fattening periods (p < 0.05); however, the serum albumin, total proteins, triglycerides, and phosphorus were increased during the fattening periods (p < 0.05). The carcass weight, longissimus muscle area and back-fat thickness were low in the long fed IRG silage group (p < 0.05). The IRG diet induced saturated fatty acids in the longissimus dorsi (p < 0.05). These results show that the IRG diet increased the serum triglycerides but reduced the glucose level at the final fattening diet and decreased the meat yield score in Hanwoo steers.