• Asian-Australasian Journal of Animal Sciences
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• 제32권1호
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• pp.1-13
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• 2019

This paper aims to critically analyse and synthesise existing knowledge concerning the use of environmental enrichment and its effect on behavior, physiology and performance of pigs housed in intensive production systems. The objective is also to provide clarity as to what constitutes successful enrichment and recommend when and how enrichment should be used. Environmental enrichment is usually understood as an attempt to improve animal welfare and to a lesser extent, performance. Common enrichment objects used are straw bedding, suspended ropes and wood shavings, toys, rubber tubings, colored plastic keys, table tennis balls, chains and strings. These substrates need to be chewable, deformable, destructible and ingestible. For enrichment to be successful four goals are essential. Firstly, enrichment should increase the number and range of normal behaviors; secondly, it should prevent the phenomenon of anomalous behaviors or reduce their frequency; thirdly, it should increase positive use of the environment such as space and fourthly it should increase the ability of the animals to deal with behavioral and physiological challenges. The performance, behavior and physiology of pigs in enriched environments is similar or in some cases slightly better when compared with barren environments. In studies where there was no improvement, it should be borne in mind that enriching the environment may not always be practical and yield positive results due to factors such as type of enrichment substrates, duration of provision and type of enrichment used. The review also identifies possible areas that still need further research, especially in understanding the role of enrichment, novelty, breed differences and other enrichment alternatives.

• 한국가금학회지
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• 제49권4호
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• pp.199-210
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• 2022

본 연구는 육계 enrichment(놀이물질) 종류 및 개수에 따른 생산성, 혈액 성상, 발바닥 피부염 및 깔짚 내 수분함량 비교 시험을 수행하였다. 육계 초생추(1일령) 수컷 1,140수를 공시하여 enrichment 3종(양배추, 알팔파 블록 및 각톱밥)과 사육수수 대비 개수(38수당 1개 또는 2개)를 설정하여 3×2 요인 시험을 수행하였다. 체중 및 사료 섭취량은 시험 개시일과 종료일(35일령) 측정하여 생산성을 조사하였다. 육계의 생리적 변화를 조사하기 위해 혈구를 분석하였으며, 발바닥피부염과 깔짚 내 수분 함량은 1, 3 및 5주령에 측정하였다. 체중 및 사료요구율은 알팔파 블록과 각톱밥 처리구가 양배추를 배치한 처리구에 비해 유의적으로 개선되었으나(P<0.05), enrichment 종류 및 개수 간의 상호작용 효과는 나타나지 않았다. 혈구 분석결과, 스트레스 지표인 HE/LY 비율이 알팔파 블록과 각톱밥 처리구에서 유의적으로 감소하였다(P<0.05). 5주령에 enrichment 종류에 따른 발바닥피부염 발생정도를 비교한 결과, 양배추(3.78), 알팔파 블록(3.06), 각톱밥(1.43) 처리구 순으로 유의적으로 감소하였으며(P<0.05), enrichment를 2개 보다 1개를 배치하였을 때 유의적으로 감소하였다(P<0.05). 5주령 깔짚 내 수분함량을 분석한 결과, 각톱밥(61.55%) 처리구에서 양배추(71.19%)와 알팔파 블록(69.50%) 처리구에 비해 유의적으로 감소하였으나(P<0.05), enrichment 종류 및 개수 간의 상호작용에는 유의적인 차이를 보이지 않았다. Enrichment로써 각톱밥 재질은 육계 사육기간 동안 생산성 및 동물복지를 향상시킬 뿐만 아니라 깔짚 수분조절제로써 활용될 수 있을 것으로 기대된다.

• Journal of Advanced Marine Engineering and Technology
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• 제27권7호
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• pp.845-851
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• 2003

The purpose of this experimental study is to investigate the quantitative pollutants reduction by oxygen enrichment and induced air effect in venturi type after-burner. For this purpose, CO, $CO_2$, $O_2$. and HC concentrations were measured before and after the after-burner by changing the Oxygen flow rate and area ratio which is defined as the ratio of air inducing area divided by total area. As results of this study, when the area ratio were increased, the emission reduction effect was increased even less oxygen flow rate. In that case when oxygen was injected too little, the pollutants were increased.

• 한국초등과학교육학회지:초등과학교육
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• 제24권4호
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• pp.465-475
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• 2005

In this study, to explore the ways of the development of the effective and desirable teaching and learning materials for the elementary science gifted, relevant previous research results were critically examined and integrated. Then a theoretical background was established and specific materials in Life Areas of elementary science was developed based on the science knowledge construction types of 'What', 'How', and 'Why'. The results could be summarized as follows: (1) The types of educational programs for the science gifted were categorized and defined as 'General-Level','Early-Growing, Fast-Growing General Level', and 'Slow-Growing Enrichment, Excellence 'Types. (2) For 5th graders, in the unit of 'Environment and living Organisms', some activities of Enrichment Type for subject on 'Changes of Living Organism with Temperature' were developed following the processes of RDPE (Research-Development-Practice-Evaluation) and their ways of using and assessment were presented. On the basis of these results, several educational implications were discussed for further research and ways of applying to the science gifted education.

• 한국수산과학회지
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• 제44권4호
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• pp.339-344
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• 2011

We investigated the effects of enrichment with oil or bacteria on the fatty acid composition of rotifers and Artemia as live prey. One enrichment(oil source) was mainly composed of squid Todarodes pacificus liver oil; the other(photosynthetic-bacterial source) was primarily made up of Schizochytrium sp. The enrichments were intended to enhance the nutritional value of the live prey, such as their EPA, DHA and n-3 HUFA contents. The lipid content as EPA and DHA of rotifers was higher when enriched with the oil source rather than the photosynthetic-bacterial source. The DHA content of Artemia nauplii after enrichment differed significantly, depending on the type of enrichment used(P<0.05). When the Artemia nauplii were enriched with the oil source, the DHA content was increased to 16.8%, whereas it increased only to 1.1% when enriched with the photosynthetic-bacterial source. These results indicate that selection of the enrichment is important for Artemia nauplii but not for rotifers.

• Genomics & Informatics
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• 제21권4호
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• pp.45.1-45.11
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• 2023

Nonalcoholic fatty liver disease (NAFLD) is a common type of chronic liver disease, with severity levels ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis (NASH). The extent of liver fibrosis indicates the severity of NASH and the risk of liver cancer. However, the mechanism underlying NASH development, which is important for early screening and intervention, remains unclear. Weighted gene co-expression network analysis (WGCNA) is a useful method for identifying hub genes and screening specific targets for diseases. In this study, we utilized an mRNA dataset of the liver tissues of patients with NASH and conducted WGCNA for various stages of liver fibrosis. Subsequently, we employed two additional mRNA datasets for validation purposes. Gene set enrichment analysis (GSEA) was conducted to analyze gene function enrichment. Through WGCNA and subsequent analyses, complemented by validation using two additional datasets, we identified five genes (BICC1, C7, EFEMP1, LUM, and STMN2) as hub genes. GSEA analysis indicated that gene sets associated with liver metabolism and cholesterol homeostasis were uniformly downregulated. BICC1, C7, EFEMP1, LUM, and STMN2 were identified as hub genes of NASH, and were all related to liver metabolism, NAFLD, NASH, and related diseases. These hub genes might serve as potential targets for the early screening and treatment of NASH.

• 생명과학회지
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• 제13권4호
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• pp.390-399
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• 2003

본 연구는 경남지역의 해수와 해산물에서 Listeria 속을 분리하여 증균배양방법에 따른 균의 분리율, 선택배지에 따른 균의 분리율, 검체에 따른 균종 별 분리율, 생화학 시험과 분리된 L. monocytogenes에 대하여는 혈청형 시험을 실시하였다. 총 100건의 검체에서 증균배양에 따른 Listeria 속의 분리율은 1일 증균배양에서 L. monocytogenes가 4% (4건), L. innocua가 35%(35건), L. ivanovii가 4%(4건), L. welshimeri가 1%(1건)였고, 7일간 증균배양에서는 L. monocytogenes가 1%(7건), L. innocua가 38%(38건), L. ivanovii가 5%(5건), L. welshimeri가 1%(1건)로 동정되어 1일 증균배양 보다 7일간의 증균배양이 Listeria속의 분리에 휠씬 효과적이었다. 이와 함께 Oxford 선택배지나 LPM 선택 배지를 사용하였을 경우 증균배양과 비교하여 검출율이 조금 낮았다. 검체에 따른 Listeria 속의 분리율은 새우와 가재에서 80%(16/20)로 분리율이 가장 높았으며, 바지락에서 50% (10/20), 해수에서 25%(5/20), 홍합에서 20%(4/20)의 순으로 나타났다. 그리고 Listeria 속의 균종 별 분리율은 L. irnnocua가 38%(38건), L. monocytogenes가 7%(7건), L. ivanovii가 5%(5건), L. welshimeri가 1%(1건)순으로 분리되었다. 각 검체에서 Listeria 속의 균종 별 분리율은 새우에서 L. innocua가 65%(13건), L. monocytogenes가 15%(3건), 가재에서 L. innocua가 70%(14건), L. monocytogenes가 10%(2건), 바지락에서 L. innocua가 45%(9건), L. monocytogenes가 5%(1건), 홍합에서 L. innocua가 10%(2건), L. monocytogenes가 5%(1건), L. welshimeri가 5%(1건), 해수에서 L. ivanovii가 25%(5건)분리되었다. L. monocytogenes로 분리 동정된 7주에 대한 혈청형 분류는 type I이 2주, type IV가 5주로 나타났다.

• 한국축산식품학회지
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• 제38권4호
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• pp.829-834
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• 2018

The objective of this study was to determine the minimum enrichment time for different types of food matrix (pork, beef, and fresh-cut lettuce) in an effort to improve Escherichia coli detection efficiency. Fresh pork (20 g), beef (20 g), and fresh-cut lettuce (20 g) were inoculated at 1, 2, and 3 Log CFU/g of Escherichia coli. Samples were enriched in filter bags for 3 or 5 h at $44.5^{\circ}C$, depending on sample type. E. coli cell counts in the samples were enriched in E. coli (EC) broth at 3 or 5 h. One milliliter of the enriched culture medium was used for DNA extraction, and PCR assays were performed using primers specific for uidA gene. To detect E. coli (uidA) in the samples, a 3-4 Log CFU/mL cell concentration was required. However, E. coli was detected at 1 Log CFU/g in fresh pork, beef, and fresh-cut lettuce after 5, 5, and 3-h enrichment, respectively. In conclusion, 5-h enrichment for fresh meats and 3-h enrichment for fresh-cut lettuce in EC broth at $44.5^{\circ}C$, and PCR analysis using uidA gene-specific primers were appropriate to detect E. coli rapidly in food samples.

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.351-359
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• 2016

The Korean Prototype Gen-IV sodium-cooled fast reactor (PGSFR) is supposed to be loaded with a relatively-costly low-enriched U fuel, while its envisaged transuranic fuels are not available for transmutation. In this work, the U-enrichment reduction by improving the neutron economy is pursued to save the fuel cost. To improve the neutron economy of the core, a new reflector material, PbO, has been introduced to replace the conventional HT9 reflector in the current PGSFR core. Two types of PbO reflectors are considered: one is the conventional pin-type and the other one is an inverted configuration. The inverted PbO reflector design is intended to maximize the PbO volume fraction in the reflector assembly. In addition, the core radial configuration is also modified to maximize the performance of the PbO reflector. For the baseline PGSFR core with several reflector options, the U enrichment requirement has been analyzed and the fuel depletion analysis is performed to derive the equilibrium cycle parameters. The linear reactivity model is used to determine the equilibrium cycle performances of the core. Impacts of the new PbO reflectors are characterized in terms of the cycle length, neutron leakage, radial power distribution, and operational fuel cost.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.81-86
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• 2005

The purpose of this study is to develop venturi type after-burner in order to obtain pollutant reduction effect and find the best stable combustion condition. For this purpose, through a flow analysis, the shape of venturi type was made and flame holder locations were also decided by measuring chemical species at before and after the after-burner. Also, various chemical species concentration were measured at changing the induced air rates and the oxygen for oxygen enrichment for the solution the problems of much oxygen flow rate and the flame stability range. As results of this study, a flow distribution and the purification effect was excellent at venturi contraction 0.5 and flame holder location 12mm below the center of Venturi throat. On the purification characteristics, we found that pollutants reduction was effective when area ratio and oxygen are increased. But there are suitable quantities due to the flame shape change and combustion efficiency.