• Asian-Australasian Journal of Animal Sciences
• /
• 제17권11호
• /
• pp.1553-1561
• /
• 2004

Two feeding trials were conducted with 128 pullets from 4 to 20 weeks of age and 96 laying hens from 23 to 63 weeks of age to evaluate the effects of scavenging and type of protein supplement on the feed intake and performance of improved pullets and laying hens. The experiments had a completely randomized design with four dietary treatments and four replicates. Treatments were: Control (Cont), scavenging but with access to a balanced concentrate at night; confinement (CF) and given the control feed ad libitum; scavenging and supplemented at night with the control feed, but with soybean meal replaced by cassava leaf meal (CLM); scavenging and supplemented at night with the control feed, but with fishmeal replaced y soybean meal (SBM). The mean daily dry matter (DMI), metabolizable energy (MEI) and crude protein intakes (CPI) of the pullets and laying hens, respectively, were 28%, and 18% higher for the confinement treatment (CF) compared to the scavenging treatments (p<0.001). The DMI, MEI and CPI of the pullets were not significantly different among scavenging treatments (p>0.05), but for the layers DMI, MEI and CPI were significantly higher for the CLM and SBM treatments compared to the Cont treatment (p<0.001). In the growing period, the average daily weight gain (ADG), supplement feed conversion ratio (FCR) and supplement feed cost/kg eggs (FCS) were not significantly different for CF compared to Cont, and among scavenging treatments (p>0.05). In the laying period, the hen-day production was significantly lower, and supplement FCR and FCS significantly higher for the CF compared to the scavenging treatments (p<0.001). Egg weight, and yolk, albumen and shell percentage and shape index were not significantly different among the scavenging treatments (p>0.05). However, shell and yolk percentages were significantly lower for the CF compared to the Cont treatment (p<0.01). Mortality was significantly higher for the CF compared to the scavenging treatments for pullets, and was significantly lower for the CF compared to scavenging treatments for laying hens (p<0.001). It was concluded that scavenging pullets and layers were getting around 28% and 18%, respectively, of their nutrient requirements from scavenging activities, resulting in correspondingly lower supplement feed conversion ratios and feed costs. Daily gains of the pullets were not affected by scavenging or protein supplement, but egg production and mortality were lower for the confined hens.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권7호
• /
• pp.997-1003
• /
• 2006

An experiment with twenty crossbred goat kids (male) of 2-3 months old, weighing about 12 kg was conducted to study the effect of feeding formaldehyde treated rape seed oil cake based diet supplemented with molasses on growth rate and histopathological changes of different organs. Goats were randomly divided into four groups of 5 animals each and were individually fed for a period of 120 days. The animals in group I (URC) and II (URCM) were fed concentrate mixture (CM-I) containing untreated rape seed oil cake (30%) while, the animals in group III (TRC) and IV (TRCM) were offered concentrate mixture (CM-II) containing formaldehyde treated rape seed oil cake. Further, molasses as energy source was additionally supplemented with the concentrate mixture at the rate of 8% of concentrate mixture on dry matter basis to animals in group II and IV. All the animals were maintained on roughage (Berseem hay:wheat straw = 2:1) and concentrate in 50:50 ratio. Average daily gain (g/d) of animals in group IV was significantly (p<0.05) higher than that in group I., but at par with group II and III. Feed conversion efficiency was also significantly (p<0.05) higher in group IV (10.14) than group I and II but at par with group III. The growth rate however increased by 50.2% in group IV showing more consistency in maintaining highest growth rate due to better balance of nutrients. At the end of four months of feeding trial, two animals from each group were sacrificed for histopathological study of different organs. Significant histopathological changes in liver, heart, lungs tissue of animals fed untreated rape seed oil cake diet were recorded which were totally absent in the organ of animals fed formaldehyde treated cake. The liver tissue of goats receiving control diet (containing untreated rape seed oil cake) were found to be associated with engorged central vein and blood vessels. Hepatocytes were swollen, pale and degenerated with cellular infiltration and fibrosis of portal areas. The muscles of heart were found to have intermyofibral edema. Emphysema accompanied by dilated and ruptured alveoli was also recorded in lung tissue. However, histopathological examination of various tissues of goats fed formaldehyde treated cake diet did not exhibit any degenerative changes. Additional supplementation of molasses with or without treated cake diet, apparently did not have any significant effect on ameliorating the above degenerative changes.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권8호
• /
• pp.1164-1170
• /
• 2005

This study was conducted to evaluate performance, breast (thigh) muscle yield, nutrient digestibility and serum biochemical parameters of broilers fed low-protein diets supplemented with various threonine to lysine ratios (Thr/Lys). Three hundred and twenty four day-old male Arbor Acres broilers were randomly allotted to six dietary treatments with six replicates per treatment and nine broilers per replicate. Six treatments included one control diet [formulated according to NRC (1994)], and five experimental diets (treatments 1-5). In treatments 1-5, the crude protein level was 2% lower than that of the NRC control diet. The Thr/Lys in treatments 1-5 was 0.65, 0.70, 0.75, 0.80 and 0.85 during the starter and grower phases and 0.70, 0.75, 0.80, 0.85 and 0.90 during the finisher phase with other nutrient levels kept consistent. The results showed that: (1) With increasing Thr/Lys, ADG of treatments 1, 3 and 4 were lower (p<0.05) than those of the NRC control diet during the starter phase; ADG of treatments 1-5 were lower (p<0.05) than those of the NRC control during the grower phase, and ADG of treatment 1 was lower (p<0.05) than that of the NRC control during the finisher phase. Average daily feed intake in treatments 1 and 4 were lower (p<0.05) than that of broilers on the NRC control diet during the grower phase. Feed/gain (F/G) of the NRC control diet was lowest (p<0.05) during the starter phase. F/G in treatments 2 and 5 were higher (p<0.05) than that of NRC during the grower phase. (2) Breast muscle proportion on d 21 increased linearly (p<0.05) in response to graded levels of Thr/Lys. (3) No differences were detected for dry matter, energy and crude protein digestibility among all seven treatments. (4) On d 21, serum triglyceride of broilers on dietary treatments 3 and 5 was higher (p<0.05) than that of broilers in control. The results indicate that the low-protein diets supplemented with an appropriate Thr/Lys could not support the same performance that was achieved by the broilers fed the NRC control diet.

• Journal of Biosystems Engineering
• /
• 제39권3호
• /
• pp.227-234
• /
• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• 대한원격탐사학회지
• /
• 제32권6호
• /
• pp.567-577
• /
• 2016

SqueeSAR 분석기법은 SAR 영상내에 있는 고정산란체(PS)와 분산산란체(DS)를 모두 이용하는 새로운 기법이다. 비록 도심지역에는 많은 PS가 존재하지만, SqueeSAR 기법은 관측밀도를 높이는데 기여할 수 있다. 차분간섭도 제작에 필요한 DEM 정확도에 의한 변위분석 결과의 영향을 분석하기 위해 SRTM 1-arc (~30 m)와 1 m LIDAR DEM을 사용한 분석을 수행하였다. 두개의 고도자료를 이용하여 PSInSAR와 SqueeSAR 분석을 수행한 결과 인공구조물과 같은 PS에서는 자료처리에 사용된 DEM 오차를 거의 정확하게 보정할 수 있기 때문에, 사용된 DEM의 정확도와 상관없이 최종 시계열 분석 결과는 동일하였다. 반면, 고정산란체가 아닌 Distributed Scatterer (DS)일 경우 사용된 DEM의 정확도에 따라 영향을 받게 되며, SqueeSAR의 경우 사용된 DEM이 정확할수록 분석 결과가 좋아짐을 확인하였다. 도심지역에서의 변위 관측에서도 SqueeSAR 기법이 PSInSAR 기법에 비해 약 5배 이상의 관측점을 추출하는데 기여했으며, 관측점의 오차도 PSInSAR 결과에 비해 현저하게 개선되었다.

• 한국농림기상학회지
• /
• 제17권1호
• /
• pp.75-84
• /
• 2015

본 연구는 국내 주요 조림수종인 백합나무 유묘의 온도 증가와 건조 스트레스에 따른 생장 및 생리 반응변화를 알아보고자 실시하였다. 온도 제어는 국립산림과학원 산림유전자원부(경기도 수원시 권선구 온정로 39)의 환경제어실 인공 광 챔버를 이용하였다. 처리 온도는 Fig. 1과 같이 최근 30년 동안(1981-2010) 우리나라 전국 월 평균을 기준으로 $-3^{\circ}C$, $0^{\circ}C$, $+3^{\circ}C$, $+6^{\circ}C$로 설정하였다. 건조 처리는 6월부터 대조구와 건조 처리구로 구분하여 대조구는 충분히 관수하여 최저 -0.1 MPa 이상의 토양 수분 포텐셜을 유지시켰고, 건조처리구는 유묘의 잎에 초기위조 현상이 나타날 때까지 관수를 하지 않았다. 온도 증가 및 건조 스트레스에 따른 백합나무 유묘의 근원경과 수고의 상대생장율은 대조구와 건조 처리구 모두 온도가 증가할수록 높은 상대 생장율을 나타냈으며, 대조구와 건조 처리간에는 차이가 없었다. 또한 백합나무 유묘의 엽면적과 총 건중량을 측정한 결과, 근원경 및 수고 생장과 같은 경향으로 온도가 증가할수록 엽면적과 총 건중량이 증가하였다. 근원경, 수고, 엽면적 및 총 건중량 모두 건조 처리구 내 $-3^{\circ}C$ 처리구에서 가장 낮은 값을 나타내 백합나무 유묘는 온도 증가보다 저온에 의해서 피해를 입는 것으로 생각된다. 광합성 속도, 암호흡 속도, 기공전도도 및 증산속도도 대조구와 건조 처리구 모두 온도가 증가할수록 증가하였고, 저온 처리구인 $-3^{\circ}C$ 처리구에서 가장 낮은 값을 보였다. 그러나 수분 이용효율은 온도가 증가할수록 감소하는 경향을 보였다. 총 엽록소 및 카로테노이드 함량도 대조구와 건조 처리구 모두 온도가 증가할수록 함량이 증가하였다. 결론적으로, 온도 증가는 백합나무 유묘의 생리적 반응에 긍정적인 영향과 함께 생장을 촉진시키는 것으로 판단된다. 그러나 온도 감소는 백합나무 유묘의 생장 및 생리적 반응에 부정적인 영향을 미쳐, 생장이 저하되는 것을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제31권8호
• /
• pp.1221-1229
• /
• 2018

Objective: A study was conducted to evaluate the varietal differences among faba bean straws and also to assess the potentials of faba bean straws supplemented with concentrate fed at the rate 70% straws and 30% concentrate mixture on feed intake, digestibility, body weight gain and carcass characteristics of the animals. Methods: Forty yearling Arsi-Bale sheep with initial body weight of $19.85{\pm}0.29kg$ (mean${\pm}$standard deviation) were grouped in a randomized complete block design into eight blocks of five animals each based on their initial body weight. Straws included in the study were from Mosisa (T1M), Walki (T2W), Degaga (T3D), Shallo (T4S), and local (T5L) varieties of faba bean and concentrate (2:1 ratio of wheat bran to "noug" seed cake). The experiment consisted of seven days of digestibility and 90 days of feeding trials followed by evaluation of carcass parameters at the end. Results: Local variety had lower (p<0.05) in grain and straw yield compared to improved varieties but higher in crude protein, metabolizable energy contents and in vitro organic matter digestibility. The apparent digestibility of dry matter and crude protein of sheep fed Walki and Mosisa straws were higher than (p<0.05) straws from Shallo varieties. Sheep fed Walki straw had greater (p<0.05) dry matter intake, average daily gain and feed conversion efficiency than sheep fed local and Shallo straws. Slaughter body weight and empty body weight were higher (p<0.05) for sheep fed Mosisa and Walki straws as compared to sheep fed Shallo straws. Apart from this, the other carcass components were not affected (p>0.05) by variety of the faba bean straws. Conclusion: There is significant varietal differences between faba bean straws both in quality and quantity. Similarly, significant variation was observed in feed intake, digestibility, body weight gain and feed conversion efficiency among sheep fed different straws of faba bean varieties with concentrate supplement. Based on these results, Walki and Mosisa varieties could be recommended as pulse crop rotation with cereals in the study area.

• 한국의학물리학회지:의학물리
• /
• 제13권4호
• /
• pp.195-201
• /
• 2002

측방 산란이 상대적으로 많은 6 MeV 전자선에 대하여 세로 자기장에서 반음영의 변화를 몬테칼로 계산을 이용하여 연구하였다. 전자의 물질과의 상호작용 계산에서 외부 자기장의 효과를 반열하기 위하여 자기장에서 전자의 방향변화에 관한 알고리즘을 개발하여 EGS4 시스템에 삽입하였다. 완성된 코드를 이용하여 점선원 기하구조를 설정하고 SSD 100 cm에서 직경 5 cm인 전자선에 대하여 0-3 T의 세로 자기장이 걸려있는 팬텀속 1.5 cm, 2.0 cm, 2.4 cm 깊이에서의 빔 프로파일을 계산하였다. 자기장의 세기에 따른 반음영의 감소를 나타내기 위해 같은 질이에서의 기존 반음영의 폭과 자기장에 의한 반음영 폭의 감소 비로 반음영 감소율(PRR)을 정의하였다. 계산결과 팬텀속 1.5 cm, 2.0 cm, 2.4 cm 깊이에 대하여 자기장의 세기가 2 T인 경우에 PRR은 각각 27%, 36%, 36%로 나타났으며, 3 T인 경우에는 각각 46%, 50%, 50%로 나타났다 0.5 T와 1 T에서는 자기장의 효과가 매우 미약하였다. 이 결과는 6 MeV 전자선의 경우에 2 T 이상의 자기장을 세로방향으로 인가한는 경우에 측방산란된 전자들이 자기장에 의하여 편향되면서 반음영의 폭이 크게 줄어드는 것으로 해석할 수 있다. 결론적으로 전자선치료에서 세로 자기장을 병행하는 경우에 조사면 가장자리의 선량감소가 보상됨으로써 치료효과의 증대를 기대할 수 있다.

• Nuclear Engineering and Technology
• /
• 제15권3호
• /
• pp.197-206
• /
• 1983

핵연료로서 사용 가능한 O/U비 범위인 2.005～2.01의 이산화 우라늄의 소결체를 환원 공정을 거치지 않고 직접 $CO_2$/CO 혼합깨스 분위기에서 소결하였다. O/U비 변화가 소결속도에 미치는 영향을 소결후기에서 조사하였으며, 일정 O/U비에 있어서의 소결 온도-시간-밀도-입도 간의 관계를 나타내는 소결 다이아그램을 결정하였다. 그결과 소결분위기중의 산소분압만을 조절하여, 이론밀도의 95%이상, 평균입도 7$\mu\textrm{m}$ 이상의 소결체를 1050$^{\circ}$～120$0^{\circ}C$의 저온에서 쉽게 얻을 수 있었다. 소결후기의 결정입도의 성장속도는 D=(Kt)$^{1}$4/의 실험식에 따르고, 결정립성장에 대한 활성화 에너지는 O/U비가 2,005, 2.01, 2.10일 때 각각 75, 64, 62Kcal/mol이었다. O/U비가 변화해도 활성화 에너지는 크게 변하지 않았지만, 소결은 산소 분압의 증가에 따라 크게 증가하였다.

• 전기화학회지
• /
• 제14권1호
• /
• pp.1-8
• /
• 2011

이온성 액체는 일정한 온도 범위에서 액체로 존재하는 이온성 염으로, 유기 양이온과 유기 또는 무기 음이온의 이온결합으로 이루어져 있다. 본 연구에서는 이온성 액체를 CdSe/ZnS 반도체 나노입자 합성의 리간드 및 용매로 사용하여 이들이 나노입자의 형태와 결정 구조에 미치는 영향에 대해서 연구하였다. CdSe/ZnS 나노입자는 용매로 알킬기의 길이가 다른 imidazolium 계열; 1-R-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([RMIM][TFSI]), R = ethyl ([EMIM]), butyl ([BMIM]), hexyl ([HMIM]), octyl ([OMIM]), 을 사용하여, 평균 크기는 약 8~9 nm 이고 두 상 zinc-blende 및 wurtzite 혼합물로 합성하는 것을 성공하였다. 또한, CdSe/ZnS 나노입자는 trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide ([$P_{6,6,6,14}$][TFSI]) 이온성 액체와 octadecene (ODE)의 혼합 용액을 사용하여 합성하였다. [$P_{6,6,6,14}$][TFSI]의 부피비가 증가함에 따라 나노입자의 결정 구조가 zinc-blende 구조에서 wurtzite 구조로 조절되었다. 또한 나노입자의 평균 크기는 약 5.5 nm 로써 [RMIM][TFSI] 를 사용했을 때 보다 더 작게 합성되었다. 이처럼 이온성 액체에 의해서 나노입자의 크기뿐 만 아니라 결정 구조도 조절할 수 있음을 처음으로 증명하였다.