• 제목/요약/키워드: genetic factors

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하이브리드 유전 알고리듬을 이용한 자동 동조 퍼지 제어기의 설계 (Design of Auto-Tuning Fuzzy Logic Controllers Using Hybrid Genetic Algorithms)

  • 류동완;권재철;박성욱;서보혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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    • pp.126-129
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    • 1997
  • This paper propose a new hybrid genetic algorithm for auto-tunig auzzy controller improving the performance. In general, fuzzy controller used pre-determine d moderate membership functions, fuzzy rules, and scaling factors, by trial and error. The presented algorithm estimates automatically the optimal values of membership functions, fuzzy rules, and scaling factors for fuzzy controller, using hybrid genetic algorithms. The object of the proposed algorithm is to promote search efficiency by overcoming a premature convergence of genetic algorithms. Hybrid genetic algorithm is based on genetic algorithm and modified gradient method. Simulation results verify the validity of the presented method.

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Association Study Between Genetic Polymorph isms in Interleukin-1 Gene Family and Adult Periodontitis in Korean

  • Kang, ByungYong;Kang, Chin Yang;Lee, Kang Oh
    • Toxicological Research
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    • 제20권4호
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    • pp.299-305
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    • 2004
  • Adult periodontitis (AP) is a chronic inflammatory disease whose etiology is not well defined. Some studies suggested that the clinical characteristics of this disease may be in part explained by genetic factors, and some attempts to find genetic markers for this disease were successful. The interleukin-1 (IL-1) gene family as one of genetic factors may influence the expression of adult periodontitis. The aim of present study is to investigate the frequencies of genetic polymorphisms in the IL-1 gene family encoding three genes (IL-1A, IL-1B and IL-1RN) in Korean AP patients and periodontically healthy controls. There were no significant differences in genotype and allele frequencies of these polymorph isms between two groups, respectively. However, -511 polymorphism of IL-1 B gene was significantly associated with mean pocket depth (MPD, mm) value in AP patients (P<0.05). Therefore, our results suggest that -511 polymorphism in the IL-1B gene may be useful as a genetic marker for the severity of AP in Koreans.

Gene-Diet Interaction on Cancer Risk in Epidemiological Studies

  • Lee, Sang-Ah
    • Journal of Preventive Medicine and Public Health
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    • 제42권6호
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    • pp.360-370
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    • 2009
  • Genetic factors clearly play a role in carcinogenesis, but migrant studies provide unequivocal evidence that environmental factors are critical in defining cancer risk. Therefore, one may expect that the lower availability of substrate for biochemical reactions leads to more genetic changes in enzyme function; for example, most studies have indicated the variant MTHFR genotype 677TT is related to biomarkers, such as homocysteine concentrations or global DNA methylation particularly in a low folate diet. The modification of a phenotype related to a genotype, particularly by dietary habits, could support the notion that some of inconsistencies in findings from molecular epidemiologic studies could be due to differences in the populations studied and unaccounted underlying characteristics mediating the relationship between genetic polymorphisms and the actual phenotypes. Given the evidence that diet can modify cancer risk, gene-diet interactions in cancer etiology would be anticipated. However, much of the evidence in this area comes from observational epidemiology, which limits the causal inference. Thus, the investigation of these interactions is essential to gain a full understanding of the impact of genetic variation on health outcomes. This report reviews current approaches to gene-diet interactions in epidemiological studies. Characteristics of gene and dietary factors are divided into four categories: one carbon metabolism-related gene polymorphisms and dietary factors including folate, vitamin B group and methionines; oxidative stress-related gene polymorphisms and antioxidant nutrients including vegetable and fruit intake; carcinogen-metabolizing gene polymorphisms and meat intake including heterocyclic amins and polycyclic aromatic hydrocarbon; and other gene-diet interactive effect on cancer.

Physiological and Nutritional Factors for Efficient Sporulation and Toxin Formation in Bacillus tthuringiensis

  • 이은희;반재구;김정일
    • 한국미생물생명공학회:학술대회논문집
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    • 한국미생물생명공학회 1986년도 추계학술대회
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    • pp.522.2-522
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    • 1986
  • In order to optimally induce sporulation and toxin formation in Bacillus thuringiensis, exhaustion of specific nutrients as well as resuspension experiments were tried. Sporulation and toxin formation was most abunduntly occurred when the growth was limited by carbon source. It was also occurred in a resuspension medium containing only distilled water. Various environmental and physiological factors affecting the efficiencies of spore and toxin formation were examined in chemically defined media. As a result of these studies, a batch fermentation resulted in higher spore and toxin yield than ever reported

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Genetic factors in precocious puberty

  • Shim, Young Suk;Lee, Hae Sang;Hwang, Jin Soon
    • Clinical and Experimental Pediatrics
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    • 제65권4호
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    • pp.172-181
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    • 2022
  • Pubertal onset is known to result from reactivation of the hypothalamic-pituitary-gonadal (HPG) axis, which is controlled by complex interactions of genetic and nongenetic factors. Most cases of precocious puberty (PP) are diagnosed as central PP (CPP), defined as premature activation of the HPG axis. The cause of CPP in most girls is not identifiable and, thus, referred to as idiopathic CPP (ICPP), whereas boys are more likely to have an organic lesion in the brain. ICPP has a genetic background, as supported by studies showing that maternal age at menarche is associated with pubertal timing in their offspring. A gain of expression in the kisspeptin gene (KISS1), gain-of-function mutation in the kisspeptin receptor gene (KISS1R), loss-of-function mutation in makorin ring finger protein 3 (MKRN3), and loss-of-function mutations in the delta-like homolog 1 gene (DLK1) have been associated with ICPP. Other genes, such as gamma-aminobutyric acid receptor subunit alpha-1 (GABRA1), lin-28 homolog B (LIN28B), neuropeptide Y (NPYR), tachykinin 3 (TAC3), and tachykinin receptor 3 (TACR3), have been implicated in the progression of ICPP, although their relationships require elucidation. Environmental and socioeconomic factors may also be correlated with ICPP. In the progression of CPP, epigenetic factors such as DNA methylation, histone posttranslational modifications, and non-coding ribonucleic acids may mediate the relationship between genetic and environmental factors. CPP is correlated with short- and long-term adverse health outcomes, which forms the rationale for research focusing on understanding its genetic and nongenetic factors.

Navigating the landscape of clinical genetic testing: insights and challenges in rare disease diagnostics

  • Soo Yeon Kim
    • Childhood Kidney Diseases
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    • 제28권1호
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    • pp.8-15
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    • 2024
  • With the rapid evolution of diagnostic tools, particularly next-generation sequencing, the identification of genetic diseases, predominantly those with pediatric-onset, has significantly advanced. However, this progress presents challenges that span from selecting appropriate tests to the final interpretation of results. This review examines various genetic testing methodologies, each with specific indications and characteristics, emphasizing the importance of selecting the appropriate genetic test in clinical practice, taking into account factors like detection range, cost, turnaround time, and specificity of the clinical diagnosis. Interpretation of variants has become more challenging, often requiring further validation and significant resource allocation. Laboratories primarily classify variants based on the American College of Medical Genetics and Genomics and the Association for Clinical Genomic Science guidelines, however, this process has limitations. This review underscores the critical role of clinicians in matching patient phenotypes with reported genes/variants and considering additional factors such as variable expressivity, disease pleiotropy, and incomplete penetrance. These considerations should be aligned with specific gene-disease characteristics and segregation results based on an extended pedigree. In conclusion, this review aims to enhance understanding of the complexities of clinical genetic testing, advocating for a multidisciplinary approach to ensure accurate diagnosis and effective management of rare genetic diseases.

Biomarkers and genetic factors for early prediction of pre-eclampsia

  • Kim, Hannah;Shim, Sung Shin
    • Journal of Genetic Medicine
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    • 제14권2호
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    • pp.49-55
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    • 2017
  • Pre-eclampsia is known to cause considerable maternal morbidity and mortality. Thus, many studies have examined the etiopathogenesis of pre-eclampsia. While many pathophysiological factors related to pre-eclampsia have been identified, the precise etiopathogenesis of pre-eclampsia remains unclear. Numerous studies have identified factors for the early prediction for pre-eclampsia to lead to preparation and closer observation on pre-eclampsia when it occurs. This article reviews on current studies of biomarkers and genetic factors related to pre-eclampsia, which may be important for developing strategies for early prediction of pre-eclampsia.

The Design of Fuzzy Controller Based on Genetic Optimization and Neurofuzzy Networks

  • Oh, Sung-Kwun;Roh, Seok-Beom
    • Journal of Electrical Engineering and Technology
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    • 제5권4호
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    • pp.653-665
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    • 2010
  • In this study, we introduce a neurofuzzy approach to the design of fuzzy controllers. The development process exploits key technologies of Computational Intelligence (CI), namely, genetic algorithms (GA) and neurofuzzy networks. The crux of the design methodology deals with the selection and determination of optimal values of the scaling factors of fuzzy controllers, which are essential to the entire optimization process. First, the tuning of the scaling factors of the fuzzy controller is carried out. Next, we form a nonlinear mapping for the scaling factors, which are realized by GA-based neurofuzzy networks by using a fuzzy set or fuzzy relation. The proposed approach is applied to control nonlinear systems like the inverted pendulum. Results of comprehensive numerical studies are presented through a detailed comparative analysis.

Fuzzy Controller Design by Means of Genetic Optimization and NFN-Based Estimation Technique

  • Oh, Sung-Kwun;Park, Seok-Beom;Kim, Hyun-Ki
    • International Journal of Control, Automation, and Systems
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    • 제2권3호
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    • pp.362-373
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    • 2004
  • In this study, we introduce a noble neurogenetic approach to the design of the fuzzy controller. The design procedure dwells on the use of Computational Intelligence (CI), namely genetic algorithms and neurofuzzy networks (NFN). The crux of the design methodology is based on the selection and determination of optimal values of the scaling factors of the fuzzy controllers, which are essential to the entire optimization process. First, tuning of the scaling factors of the fuzzy controller is carried out, and then the development of a nonlinear mapping for the scaling factors is realized by using GA based NFN. The developed approach is applied to an inverted pendulum nonlinear system where we show the results of comprehensive numerical studies and carry out a detailed comparative analysis.

Obesity: Interactions of Genome and Nutrients Intake

  • Doo, Miae;Kim, Yangha
    • Preventive Nutrition and Food Science
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    • 제20권1호
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    • pp.1-7
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    • 2015
  • Obesity has become one of the major public health problems all over the world. Recent novel eras of research are opening for the effective management of obesity though gene and nutrient intake interactions because the causes of obesity are complex and multifactorial. Through GWASs (genome-wide association studies) and genetic variations (SNPs, single nucleotide polymorphisms), as the genetic factors are likely to determine individuals' obesity predisposition. The understanding of genetic approaches in nutritional sciences is referred as "nutrigenomics". Nutrigenomics explores the interaction between genetic factors and dietary nutrient intake on various disease phenotypes such as obesity. Therefore, this novel approach might suggest a solution for the effective prevention and treatment of obesity through individual genetic profiles and help improve health conditions.