• Title/Summary/Keyword: Agricultural Population

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영농방법이 논에 서식하는 미꾸리 개체군의 체중-체장 관계에 미치는 영향 (Influence of Farming Practices on Weight-Length Relationship of the Loach (Misgurnus anguillicaudatus) Population in Rice Paddy Fields)

  • 김명현;최순군;어진우;권순익;송영주
    • 환경생물
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    • 제35권4호
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    • pp.446-451
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    • 2017
  • 친환경농법과 관행농법으로 대별되는 영농방법이 논 생태계에 서식하는 미꾸리 개체군에 미치는 영향을 파악하기 위하여 2014년 9월에 친환경 논과 관행 논에서 미꾸리망을 이용하여 미꾸리 개체군의 빈도분포 및 무게-길이 상관관계를 조사하였다. 그 결과 채집된 전체 미꾸리의 발육단계별 개체수 빈도분포는 큰 차이를 나타냈다. 미꾸리의 무게와 길이의 평균값은 친환경 논이 관행 논보다 큰 것으로 나타났지만, 범위는 관행 논이 높게 나타났다. 무게-길이 상관관계식은 친환경 논과 관행 논에서 각각 $W=0.000004L^{3.0747}$, $W=0.000002L^{3.2106}$으로 나타났다. 평균 비대지수(K)는 친환경 논이 0.95로 관행 논 0.67보다 높게 나타났다. 결과적으로 영농방법이 논에 서식하는 미꾸리 개체군의 발육에 영향을 미치는 것으로 파악되었다.

Modeling Growth Kinetics of Lactic Acid Bacteria for Food Fermentation

  • Chung, Dong-Hwa;Kim, Myoung-Dong;Kim, Dae-Ok;Koh, Young-Ho;Seo, Jin-Ho
    • Food Science and Biotechnology
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    • 제15권5호
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    • pp.664-671
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    • 2006
  • Modeling the growth kinetics of lactic acid bacteria (LAB), one of the most valuable microbial groups in the food industry, has been actively pursued in order to understand, control, and optimize the relevant fermentation processes. Most modeling approaches have focused on the development of single population models. Primary single population models provide fundamental kinetic information on the proliferation of a primary LAB species, the effects of biological factors on cell inhibition, and the metabolic reactions associated with cell growth. Secondary single population models can evaluate the dependence of primary model parameters, such as the maximum specific growth rate of LAB, on the initial external environmental conditions. This review elucidates some of the most important single population models that are conveniently applicable to the LAB fermentation analyses. Also, a well-defined mixed population model is presented as a valuable tool for assessing potential microbial interactions during fermentation with multiple LAB species.

승수이론을 이용한 지속가능한 지역경제성장모델의 개발 (Development of a Sustainable Regional Economic Growth Model (SREG) Using Multiplier Theory)

  • 정남수
    • 한국농공학회논문집
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    • 제49권1호
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    • pp.35-42
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    • 2007
  • This paper develops a Sustainable Regional Economic Growth Model (SREG) which estimates the relation of labor population change and employment increase in each occupation and maximum limits and minimum requirements of employment increase by labor population change in a specified region using multiplier theory. To develop the proposed model, sustainable regional economic growth is defined as a steady increase of labor population over a long term period and the limit of employment increase is defined as the estimated labor population change in the region with no need for commutation from the surrounded areas. Developed model was applied to 67 county in Pennsylvania State and the results revealed that the investment in infrastructure occupations, such as transportation, warehousing, utilities, information, communication, and other public utilities, maximizes the effects for increasing employment, whereas finance, insurance, and real estate occupations have minimum effects for increasing employment. Calculated minimum requirements of occupations show that infra-structure occupations is a critical factor for labor population change and maximum limits of occupations show that agriculture and finance occupations are difficult to increase independently.

National genomic evaluation of Korean thoroughbreds through indirect racing phenotype

  • Lee, Jinwoo;Shin, Donghyun;Kim, Heebal
    • Animal Bioscience
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    • 제35권5호
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    • pp.659-669
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    • 2022
  • Objective: Thoroughbred horses have been bred exclusively for racing in England for a long time. Additionally, because horse racing is a global sport, a healthy leisure activity for ordinary citizens, and a high-value business, systematic racehorse breeding at the population level is a requirement for continuous industrial development. Therefore, we established genomic evaluation system (using prize money as horse racing traits) to produce spirited, agile, and strong racing horse population Methods: We used phenotypic data from 25,061 Thoroughbred horses (all registered individuals in Korea) that competed in races between 1994 and 2019 at the Korea Racing Authority and constructed pedigree structures. We quantified the improvement in racehorse breeding output by year in Korea, and this aided in the establishment of a high-level horse-fill industry. Results: We found that pedigree-based best linear unbiased prediction method improved the racing performance of the Thoroughbred population with high accuracy, making it possible to construct an excellent Thoroughbred racehorse population in Korea. Conclusion: This study could be used to develop an efficient breeding program at the population level for Korean Thoroughbred racehorse populations as well as others.

집단생잔모델에 변화할당효과를 고려한 농촌지역 인구모델의 개발 (Development of a Rural Population Model Considering Shift-Share Effects in Cohort-Survival Method)

  • 정남수;이행우
    • 농촌계획
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    • 제12권3호
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    • pp.39-42
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    • 2006
  • The purpose of this study is to develop rural population model adapting cohort survival method with sift-share effects. Administrative district in this study is below Myun: about 2,000 population. Population data of rural area in 1990, 1995, and 2000 by age cohort were selected for applying developed model. Damping coefficient from population data was calculated as 7% and results applying this coefficient in rural population data below the error from 12% to 1.06%. In detail, most of cohorts fitted with developed model except from 15 to 29 age groups. Application result of small population area; DaesulMyun revealed that main factor of population change is not natural change but migration.

Study on the Development of a Probiotics Complex for Weaned Pigs

  • Xuan, Z.N.;Kim, J.D.;Heo, K.N.;Jung, H.J.;Lee, J.H.;Han, Y.K.;Kim, Y.Y.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권10호
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    • pp.1425-1428
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    • 2001
  • This study was conducted to investigate the effects of supplementation of a probiotics complex on growth performance, nutrient digestibility, diarrhea score and microbial population in pigs weaned at 21 days of age. Treatments were 1) control A (0.2% antibiotics, Avilamycin), 2) control B (0.1 % $Ractocom^{(R)}$), 3) 0.1%, 4) 0.2% and 5) 0.3% probiotics complex; 80 pigs were used and each treatment had 4 replicates with 4 pigs per replicate (16 pigs per treatment). During phase I period (d 0 to 14), although there was no significant difference, pigs fed control B diet showed higher ADG (average daily gain) and better F/G (feed/gain) than any other treatments. During late experimental period (d 15 to 28), pigs fed diet supplemented with 0.2% probiotics complex showed slightly higher ADG. Overall (d 0 to 28) the diet that contained 0.2% probiotics complex gave slightly higher ADG and ADFI (average daily feed intake) than the other diets. In a metabolic trial using 20 piglets, nutrient digestibility showed the best results in pigs fed 0.2% probiotics complex diet, but not significantly different from other groups. Diarrhea score and microbial population status in intestine, colon and feces were not affected by dietary treatments. In conclusion, this study suggested that a newly developed probiotics complex can replace antibiotics in weaned pigs.

Analysis of cross-population differentiation between Thoroughbred and Jeju horses

  • Lee, Wonseok;Park, Kyung-Do;Taye, Mengistie;Lee, Chul;Kim, Heebal;Lee, Hak-Kyo;Shin, Donghyun
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권8호
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    • pp.1110-1118
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    • 2018
  • Objective: This study was intended to identify genes positively selected in Thoroughbred horses (THBs) that potentially contribute to their running performances. Methods: The genomes of THB and Jeju horses (JH, Korean native horse) were compared to identify genes positively selected in THB. We performed cross-population extended haplotype homozygosity (XP-EHH) and cross-population composite likelihood ratio test (XP-CLR) statistical methods for our analysis using whole genome resequencing data of 14 THB and 6 JH. Results: We identified 98 (XP-EHH) and 200 (XP-CLR) genes that are under positive selection in THB. Gene enrichment analysis identified 72 gene ontology biological process (GO BP) terms. The genes and GO BP terms explained some of THB's characteristics such as immunity, energy metabolism and eye size and function related to running performances. GO BP terms that play key roles in several cell signaling mechanisms, which affected ocular size and visual functions were identified. GO BP term Eye photoreceptor cell differentiation is among the terms annotated presumed to affect eye size. Conclusion: Our analysis revealed some positively selected candidate genes in THB related to their racing performances. The genes detected are related to the immunity, ocular size and function, and energy metabolism.