• 한국초등과학교육학회지:초등과학교육
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• 제33권2호
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• pp.306-321
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• 2014

This study aims to analyze difficulties that pre-service elementary teachers experience in investigating the life cycle of a common cabbage butterfly in person. As difficulties they face during the process of this research, they pointed out collecting eggs, observing molting, creating environments for a breeding cage, feeding, building a breeding cage, and making butterfly specimens. Out of all the environmental difficulties related to their school fields, they pointed out a difficulty of time management most of all, followed by placing a breeding cage in the classroom and the lack of microscopes for observation. In regard to difficulties related to their evaluations on students' activities, they found it difficult to evaluate students' activity with the life cycle of an insect in the aspect of knowledge and even to set evaluation criteria. Besides, many of them responded that it would be appropriate to evaluate a research on the life cycle of an insect through a portfolio or an observation journal. In regard to difficulties in terms of teachers' knowledge, they found it difficult to understand insect molting, metamorphoses, complete metamorphoses, incomplete metamorphoses, the structure of an insect body, and how to distinguish a female insect from a male one. In regard to the application of class models, they knew it is important for students to have various experiences through direct observation, so the experience-based learning model was proper for the process of observing the life cycle of a common cabbage butterfly. However, they found it difficult for students to observe each stage of the life cycle in person.

• 한국세라믹학회지
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• 제35권5호
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• pp.451-457
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• 1998

$Li_2$$ZrO_3$ powder which is one of the candidates of breeding materials for the fusion reactor was syn-thesized by a precipitation-combustion process. Although precipitates from the reaction between zirconium nitrate and citric acid were existed in a precursor solution. $Li_2$$ZrO_3$ could easily be obtained by using the mixed fuel of urea and citric acid in stoichiometric composition. The phases of as-synthesized powder con-sisted of $Li_2$$ZrO_3$ and small amounts of $Li_6$$Zr_2O_3$ and $Li_2$$ZrO_3$ The latter phases disappeared after the cal-cination at $1100^{\circ}C$ for 2 h. The primary particle size and the specific surface area of as-synthesized powders were smaller than 20nm and 10-14 $M^2$/g, respectively. The primary particle size of the precipitation-combustion synthesized powders was affected by the size of precipitates present in a precursor solution.

• Asian-Australasian Journal of Animal Sciences
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• 제25권3호
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• pp.299-303
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• 2012

Inbreeding is the mating of relatives that produce progeny having more homozygous alleles than non-inbred animals. Inbreeding increases numbers of recessive alleles, which is often associated with decreased performance known as inbreeding depression. The magnitude of inbreeding depression depends on the level of inbreeding in the animal. Level of inbreeding is expressed by the inbreeding coefficient. One breeding goal in livestock is uniform productivity while maintaining acceptable inbreeding levels, especially keeping inbreeding less than 20%. However, in closed herds without the introduction of new genetic sources high levels of inbreeding over time are unavoidable. One method that increases selection response and minimizes inbreeding is selection of individuals by weighting estimated breeding values with average relationships among individuals. Optimum genetic contribution theory (OGC) uses relationships among individuals as weighting factors. The algorithm is as follows: i) Identify the individual having the best EBV; ii) Calculate average relationships ($\bar{r_j}$) between selected and candidates; iii) Select the individual having the best EBV adjusted for average relationships using the weighting factor k, $EBV^*=EBV_j(1-k\bar{{r}_j})$ Repeat process until the number of individuals selected equals number required. The objective of this study was to compare simulated results based on OGC selection under different conditions over 30 generations. Individuals (n = 110) were generated for the base population with pseudo random numbers of N~ (0, 3), ten were assumed male, and the remainder female. Each male was mated to ten females, and every female was assumed to have 5 progeny resulting in 500 individuals in the following generation. Results showed the OGC algorithm effectively controlled inbreeding and maintained consistent increases in selection response. Difference in breeding values between selection with OGC algorithm and by EBV only was 8%, however, rate of inbreeding was controlled by 47% after 20 generation. These results indicate that the OGC algorithm can be used effectively in long-term selection programs.

• Journal of Plant Biotechnology
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• 제47권1호
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• pp.15-25
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• 2020

Allium L. is one of the largest genera of the Amaryllidaceae family, with more than 920 species including many economically important species used as vegetables, spices, medicines, or ornamental plants. Currently, DNA barcoding tools are being successfully used for the molecular taxonomy of Allium. A total of 46 Allium species were collected from their native areas, and DNA was extracted using the IBRC DNA extraction kit. We used specific primers to PCR amplify matK. DNA sequences were edited and aligned for homology, and a phylogenetic tree was constructed using the neighbor-joining method. The results show thymine (38.5%) was the most frequent and guanine (13.9%) the least frequent nucleotide. The matK regions of the populations were quite highly conserved, and the amount of C and CT was calculated at 0.162 and 0.26, respectively. Analysis of the nucleotide substitution showed C-T (26.22%) and A-G (8.08%) to have the highest and lowest percent, respectively. The natural selection process dN/dS was 1.16, and the naturality test results were -1.5 for Tajima's D and -1.19 for Fu's Fs. The NJ dendrogram generated three distinct clades: the first contained Allium austroiranicum and A. ampeloprasum; the second contained A. iranshahrii, A. bisotunense, and A. cf assadi; and the third contained A. rubellum and other species. In this study, we tested the utility of the matK region as a DNA barcode for discriminating Allium. species.

• Journal of Applied Biological Chemistry
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• 제61권4호
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• pp.305-314
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• 2018

'New Breeding Techniques (NBTs)' have been one of hot issues, since their future will be affected profoundly by national as well as international regulatory landscapes. In this review, we compare characteristics of NBTs with conventional and genetic modification, and analyze genetically modified organism (GMO) regulatory systems in the context of possible regulation of NBTs. NBTs are very heterogeneous in terms of principles, methodologies, and final products. As Living Modified Organisms (LMO) is defined in the Cartagena Protocol on Biosafety (CPB) as an organism containing novel combination of genetic materials obtained by the use of modern biotechnology, CPB as well as other national legislations locate itself somewhere in the middle between product-based and process-based regulations. It is also noted that jurisdictions with regulatory systems more oriented to product-based one tend to be more productive and decide or may decide to exempt site-directed nucleases-1 from GMO regulation. In this context, Korean legislations are reviewed to clarify the commons and differences in GMO definitions. Act on Transboundary Movement of LMO Act, Food Sanitation Act and Agricultural and Fishery Products Quality Control Act are three major acts to regulate GMOs. It is noted that there are differences in the definition of LMO or GM food/products especially between the LMO Act and the Food Sanitation Act. Such differences may cause conflicts between Acts when policy-decision regarding the regulation of NBTs is made. Therefore, it is necessary to reorganize legislations before policies regarding the regulation of any techniques from biotechnology are made.

• Animal Bioscience
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• 제34권8호
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• pp.1283-1289
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• 2021

Objective: The progestogen-associated endometrial protein (PAEP) gene encodes the main whey protein in milk, β-lactoglobulin. The aim of the study was to investigate polymorphism in the PAEP gene and its association with milk yield, composition, and quality. Methods: Test-day records for 782 dairy cows were analysed. A total of 10 single nucleotide polymorphisms (SNP) within the PAEP gene were investigated. The following parameters were recorded: milk yield (MY, kg/d), percent milk fat (%), protein (PP, %), dry matter (DMP, %) and lactose (LP, %), urea content (UC, mg/L) as well as natural logarithm for somatic cell count (LnSCC, ln). Effect on genomic estimated breeding values accuracy was evaluated with pedigree and single step model. Results: Results show that only three SNPs were polymorphic, creating 5 composite genotypes: P1 to P5. Differences in MY between composite genotypes were noted in the two tested herds. Cows with P5 composite genotypes were characterised by the highest PP and LnSCC and the lowest LP and UC (p<0.05). P4 was linked to an increased DMP and UC, while P3 to an increase in LP and decrease in PP and LnSCC. Both factors are important markers in herd management and have high influences on the herds economics. For 5 out of 7 traits the accuracy of prediction was improved by including the haplotype as a fixed effect. Conclusion: Presented results may suggest a new way to optimise breeding programmes and demonstrate the impact of using genomic data during that process.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권1호
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• pp.77-81
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• 2002

A new non-cocooning silkworm variety, Hachojam, suitable for autumn rearing season is single cross Fl hybrid between Japanese race Jam 307 and Chinese race Jam 126. Jam 307, Japanese parent of the Hachojam, which is a source for non-cocooning process showed a high GCA (generation combining ability) in naked pupation rate and Jam 126, Chinese parent, showed a high GCA in pupation rate and single pupal weight. In the local adaptability test performed at 8 local areas in autumn of 1999 to 2000, the naked pupation rate and thin cocoon rate of Hachojam were 64.7% and 35.3% , respectively. The pupal weight calculated from 10,000 of the 3rd molted larvae was 24% heavier in Hachcjam than the cocoon-producing, check variety Daesungjam.

• Journal of Ginseng Research
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• 제24권1호
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• pp.1-7
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• 2000

To develop a new ginseng variety with good quality and high yielding, a lot of individual ginseng plant were selected in the farmers′ fields in 1968. Among them, a promising line, 680-98-2, has been developed through comparative cultivation of several lines selected with pure line separation from local races in Korea Ginseng & Tobacco Research Institute. Preliminary and advanced yield trials were performed for 8 years. 1) One of them was designated as KG102 and it was then registered as a new variety "Yunpoong" with the regional yield and adaptation trials for 10 years (1981-1990) on November 30, 1998 in Korea.2) For the root characters, the diameter of taproot and ratio of the taproot length to the diameter of Yunpoong were bigger and lower than those of Jakyungiong. Root yield was 27.3% higher in Yunpoong than Jakyungiong.

• 한국자원식물학회지
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• 제10권2호
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• pp.200-210
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• 1997

The understanding on the plant genome is accelerated with the fast advance of molecular biological techniques. The molecular dissecting of the plant genome has made possible the precise genotyping the plants, which can be utilized for molecular breeding program. As well, the molecular cloning of genes interested can facilitate the process of gene transfer between intra-and inter-generic taxa. Moreover, the manipulation of the agronomically important QTL genes, which can be rarely performed by the conventional genetic methods, is also possible by the utilization of molecular markers. In addition to these genetical applications, molecular markers are useful in the areas of plant taxonomy and management of germplasm by fingerprinting analysis. This paper describes the theoretical aspects marker technologies and practical applications of each marker technique.

• 생명과학회지
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• 제28권1호
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• pp.130-139
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• 2018

말을 활용한 경주는 고대 유럽의 여러 국가들에서 마차 경주 혹은 산악 경주 등의 형태로 이루어졌으며, 고대 그리스 올림픽에서 마차 경주가 정식 종목으로 채택되었다. 서러브레드종은 17세기부터 속도, 체력, 그리고 경주 능력을 위해 선택적으로 교배되었다. 그 결과, 18세기부터 귀족들이 향유하는 스포츠로서 서러브레드종을 활용한 경주가 시행되었다. 이후 여러 국가에서 각기 다양한 형태로 발달하여 현재 크게 평지 경주, 장애물 경주, 마차 경주 등으로 발달하였다. 서러브레드 경주마는 300여 년 동안 강력한 선발 육종 전략에 의하여 선택되어 왔기에, 현재 우수한 경주 능력을 갖추고 있다. 말산업은 번식, 조련, 경마 등을 통하여 막대한 경제적 효과를 유발하기에, 말의 경주 능력을 유지하고 극대화하는 것이 필요하다. 최근에 많은 양의 게놈 데이터를 처리하기 위해 차세대 시퀀싱(Next Generation Sequencing; NGS)이 개발되었으며, 이 분석 기술의 현저한 발전을 토대로 우수한 형질을 가진 동물 육종 전략을 쉽게 수행 할 수 있게 되었다. 따라서 뛰어난 경주 능력을 가진 경주마를 선발 육종하기 위해서는 최신 유전체 분석 기술을 활용하는 전략이 필요하다. 본 논문에서는 경주마의 경주 능력을 향상시키기 의한 유전체 분석의 현재의 노력을 알아보고, 마지막으로 경주마와 제주마에서 유전체 분석을 활용하는 전략을 제안할 것이며, 대한민국의 생명자원인 제주마의 선발 육종 전략을 제안할 것이다. 말 산업은 기술, 사회 및 경제 분야에서 인간에게 강력한 파급 효과를 주는 동물 중 하나이다. 우리는 국내 고부가가치 말의 원천적인 유전 정보를 확보하고 선발 육종 할 수 있는 체계적인 기술을 확립하여 생산, 연구 업무 등에 대한 일자리 확보에 기여할 수 있기를 기대한다.