• 대한치과기공학회지
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• 제29권1호
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• pp.35-48
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• 2007

The purpose of this study was to evaluate shade selection using conventional visual assessment in vivo natural teeth and porcelain-fused-to-metal (PFM) crown. Maxillary central incisors, lateral incisors and canines of one hundred twenty four college women were used as vivo natural teeth. Fifty one PFM crown for maxillary central incisor fabricated by dental laboratory were used as experimental materials. Using Vitapan Classical Shade Guides, shade selection of natural teeth was measured by each college woman and shade selection of PFM crown was measured by three ceramists with more than ten years career. Both natural teeth and PFM crown shade selection were measured through Shade Eye-Ex. From the shade selection comparing, following results were obtained. The results were as follows: 1. The shade matching identification of natural teeth between the shade selection using Vitapan Classical Shade Guides and the shade selection using Shade Eye-Ex was 27.4% in maxillary central incisor, 13.7% in lateral incisor and 18.5% in canine. 2. Among the shade selection of PFM crown by three ceramists, the shade evaluation of three ceramists were same only in ten cases. In twenty case, those of two ceramists were same. 3. The shade matching identification of PFM crown between the shade selection using Vitapan Classical Shade Guides and the shade selection using Shade Eye-Ex was 38.6% in average. These results suggest that the shade selection using conventional visual assessment should be dealt with care in clinic and need a credible method for shade matching color.

• 한국동물학회지
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• 제26권2호
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• pp.95-106
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• 1983

Drosophila melanogaster의 Oregon-R 계통과 lethal free 집단을 대상으로 connected test tube apparatus를 사용하여 보행행동에 관한 rapid와 slow 행동을 방향성도태의 방법으로 15세대 동안에 걸쳐 도태하였다. 한편 10세대째부터 natural selection을 행하여 유전적 효과를 분석하였다. 1. 보행행동의 rapid와 slow 성질은 초기세대에서부터 뚜렷한 도태효과를 나타내어 제 7세대 이후에 각각 selection plateau에 달하였다. 2. 방향성 도태를 10세대 동안 실시한 후 realized heritability를 계산한 결과 rapid 성질은 $9\\sim14%$, slow 성질은 $11\\sim16%$로서 rapid행동보다 slow 행동의 유전율이 다소 높게 나타났다. 3. Rapid 성질을 지배하는 유전자와 slow 성질을 지배하는 유전자의 우열관계를 밝히기 위한 hybridization 실험결과 slow 유전자가 rapid 유전자에 대하여 partial dominance의 효과가 있었다. 4. 10세대 동안에 걸쳐 방향성 도태를 실시한 후 natural selection을 5세대 동안 실시한 결과 rapid 성질은 단 5세대만에 neutral의 상태 (6.5)로 복원되었으나 slow 성질은 모집단의 보행지수와 비교하여 전혀 변화가 없었다. 실험결과로 미루어 rapid와 slow 형질은 polygenic system에 의하여 control 되는 양적 형질임을 알았다. 한편 rapid 유전자는 natural selection에 의한 homeostasis의 효과가 있으나 slow 행동은 소수의 major gene에 의하여 지배되는 것을 알았다.

• 한국과학교육학회지
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• 제36권5호
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• pp.729-737
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• 2016

자연선택개념은 진화론의 핵심개념으로 다양한 생물학적 문제를 해결하기 위해 이해해야 될 필수 개념이다. 이 연구는 한국예비생물 교사들의 자연선택개념의 이해 수준을 조사하기 위하여 중국, 미국, 독일의 생물전공자와 비교하는 것을 목적으로 한다. 특히 이 연구에서는 자연선택개념의 두 개념요소인 생태개념과 유전개념으로 구분하여 예비생물교사의 자연선택개념을 분석하였다. 우리나라 예비생물교사 376명을 포함하여 1226명의 한국, 중국, 미국, 독일의 생물전공 예비교사의 자료를 토대로 분석하였다. 검사도구는 생태개념과 유전개념문항 각 10개씩을 포함하고 있는 Conceptual Inventory of Natural Selection의 20문항을 라쉬모델, 다변량분산분석, 일변량분산 분석을 활용하여 분석하였다. 그 결과 우리나라 예비생물교사의 자연선택개념 수준은 중국과 비슷하고 미국, 독일에 비하여 낮았다. 생태개념과 유전개념으로 구분하여 살펴보면, 우리나라 예비생물교사 1학년의 경우 중국과 독일에 비하여 유전개념이 유의미하게 낮았으며, 4학년의 경우 미국과 독일에 비하여 생태개념이 유의미하게 낮았다. 3년간의 예비생물교사 교육과정 동안 유전개념에 대한 교육은 성공적이었으나, 생태개념의 교육은 성공적이지 못하였다. 이 연구결과를 토대로 자연선택개념의 이해를 위한 예비생물 교사교육에 대해서 논의한다.

• Genomics & Informatics
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• 제6권4호
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• pp.173-180
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• 2008

The human genome has evolved as a consequence of evolutionary forces, such as natural selection. In this study, we investigated natural selection on the human genes by comparing the numbers of nonsynonymous (NS) and synonymous (S) mutations in individual genes. We initially collected all coding SNP data of all human genes from the public dbSNP. Among the human genes, we selected 3 different selection groups of genes: positively selected genes (NS/S${\geq}$3), negatively selected genes (NS/S${\leq}$1/3) and neutral selection genes (0.9

• Asian Journal of Innovation and Policy
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• 제12권2호
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• pp.261-267
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• 2023

In the paper of 'Natural Selection Favors AIs over Humans,' Dan Hendrycks applies principles of Darwinian evolution to forecast potential trajectories of AI development. He proposes that competitive pressures within corporate and military realms could lead to AI replacing human roles and exhibiting self-interested behaviors. However, such claims carry the risk of oversimplifying the complex issues of competition and natural selection without clear criteria for judging whether AI is selfish or altruistic, necessitating a more in-depth analysis and critique. Other studies, such as ''The Threat of AI and Our Response: The AI Charter of Ethics in South Korea,' offer diverse opinions on the natural selection of artificial intelligence, examining major threats that may arise from AI, including AI's value judgment and malicious use, and emphasizing the need for immediate discussions on social solutions. Such contemplation is not merely a technical issue but also significant from an ethical standpoint, requiring thoughtful consideration of how the development of AI harmonizes with human welfare and values. It is also essential to emphasize the importance of cooperation between artificial intelligence and humans. Hendrycks's work, while speculative, is supported by historical observations of inevitable evolution given the right conditions, and it prompts deep contemplation of these issues, setting the stage for future research focused on AI safety, regulation, and ethical considerations.

• 산업공학
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• 제20권4호
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• pp.458-468
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• 2007

Artificial immune systems (AIS) are one of natural computing inspired by the natural immune system. The fault detection, the pattern recognition, the system control and the optimization are major application area of artificial immune systems. This paper gives a concept of artificial immune systems and useful techniques as like the clonal selection, the immune network theory and the negative selection. A concise survey on the optimization problem based on artificial immune systems is generated. The overall performance of artificial immune systems for the optimization problem is discussed.

• Genomics & Informatics
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• 제10권2호
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• pp.81-87
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• 2012

Large-scale copy number variants (CNVs) in the human provide the raw material for delineating population differences, as natural selection may have affected at least some of the CNVs thus far discovered. Although the examination of relatively large numbers of specific ethnic groups has recently started in regard to inter-ethnic group differences in CNVs, identifying and understanding particular instances of natural selection have not been performed. The traditional $F_{ST}$ measure, obtained from differences in allele frequencies between populations, has been used to identify CNVs loci subject to geographically varying selection. Here, we review advances and the application of multinomial-Dirichlet likelihood methods of inference for identifying genome regions that have been subject to natural selection with the $F_{ST}$ estimates. The contents of presentation are not new; however, this review clarifies how the application of the methods to CNV data, which remains largely unexplored, is possible. A hierarchical Bayesian method, which is implemented via Markov Chain Monte Carlo, estimates locus-specific $F_{ST}$ and can identify outlying CNVs loci with large values of FST. By applying this Bayesian method to the publicly available CNV data, we identified the CNV loci that show signals of natural selection, which may elucidate the genetic basis of human disease and diversity.

• Asian-Australasian Journal of Animal Sciences
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• 제29권1호
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• pp.36-42
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• 2016

Milk-related traits (milk yield, fat and protein) have been crucial to selection of Holstein. It is essential to find the current selection trends of Holstein. Despite this, uncovering the current trends of selection have been ignored in previous studies. We suggest a new formula to detect the current selection trends based on single nucleotide polymorphisms (SNP). This suggestion is based on the best linear unbiased prediction (BLUP) and the Fisher's fundamental theorem of natural selection both of which are trait-dependent. Fisher's theorem links the additive genetic variance to the selection coefficient. For Holstein milk production traits, we estimated the additive genetic variance using SNP effect from BLUP and selection coefficients based on genetic variance to search highly selective SNPs. Through these processes, we identified significantly selective SNPs. The number of genes containing highly selective SNPs with p-value <0.01 (nearly top 1% SNPs) in all traits and p-value <0.001 (nearly top 0.1%) in any traits was 14. They are phosphodiesterase 4B (PDE4B), serine/threonine kinase 40 (STK40), collagen, type XI, alpha 1 (COL11A1), ephrin-A1 (EFNA1), netrin 4 (NTN4), neuron specific gene family member 1 (NSG1), estrogen receptor 1 (ESR1), neurexin 3 (NRXN3), spectrin, beta, non-erythrocytic 1 (SPTBN1), ADP-ribosylation factor interacting protein 1 (ARFIP1), mutL homolog 1 (MLH1), transmembrane channel-like 7 (TMC7), carboxypeptidase X, member 2 (CPXM2) and ADAM metallopeptidase domain 12 (ADAM12). These genes may be important for future artificial selection trends. Also, we found that the SNP effect predicted from BLUP was the key factor to determine the expected current selection coefficient of SNP. Under Hardy-Weinberg equilibrium of SNP markers in current generation, the selection coefficient is equivalent to $2^*SNP$ effect.

• 한국동물학회지
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• 제20권1호
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• pp.1-8
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• 1977

1974年 安養에서 採集한 초파리의 走光性行動에 대한 人爲淘汰實驗을 행하였다. 淘汰의 結果, 第10世代까지의 走光性 및 避光系統의 遺傳率은 每世代當 2$\\sim$4%로 나타났다. 淘汰系統間의 相對交配實驗의 結果, 避光行動을 나타내는 遺傳子가 走光性遺傳子에 대하여 部分的 優性의 효과가 있음을 알았고, 그 효과는 淘汰의 後期世代에서 더욱 뚜렷하였다. 淘汰15世代後, 走光性과 避光性系統에 대하여 人爲淘汰를 中止하고 自然淘汰에 의한 遺傳子의 行動을 調査하였다. 實驗結果, 數世代以內에 最初集團의 走光性指數로 환원되었다. 이러한 현상은 自然淘汰에 의한 遺傳的復元性의 一例라고 생각된다.

• 대한치과보철학회지
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• 제34권3호
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• pp.457-463
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• 1996

An esthetically pleasing result in denture service is dependent upon several consideration. Esthetic considerations for the edentulous patient include tooth size, shape, arrangement, positioning, gingival contour, age, sex, personality differences, and ethnic type. Especially, the form of anterior artificial teeth is an important factor on the esthetics. The selection of artificaial teeth requires understanding and knowledge on physical and biologic factors and has to meet the indivisul esthetics and functional needs of each patient. However, the selection of artificial teeth is based on the large degree of subjective judgement of the dentist, Therefore, this is one of the most unscientific processes. Many attempts have been made to find a guideline for the selection of artificial teeth. Temperamental theory by White and Hall utillized with the physical characteristics such as body size, body form, color of eyes and hair, and disposition. SPA theory by Frush and Fisher utilized with the basis of sex, personalities, and age of the indivisual. There has not been provided for a guideline and study on the selection of artificial teeth for Koreans yet. This study was aimed to evaluate the William's typal matching theory in Koreans. 1. The facial forms of korean adult were ovoid(46.3%), square(36.7%) and tapered(17.0%) form. 2. The anatomic forms of natural maxillary incisors were ovoid(45.3%), tapered(31.3%), square(23.3%) form. 3. The forms of face and natural maxillary incisors were ovoid(21.9%), squared(11%), tapered(6.3%). 4. The natural maxillary incisors were similar in form to the facial form only in 39%. There was no correlation between the form of the face and the form of natural maxillary central inisors in Koreans. 5. Artificaial teeth which was selected according to the typal matching theory did not represent the form of the natural teeth in 61 per cents of the fatal, but it felt that they harmonized with the form of the patient's face and produced good results.