• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.139-147
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• 1999

Rapid Prototyping has made a drastic change in all industries which needs to reduce the time for the development of new products. Orientation and packing in rapid prototyping is considered as the most important factors to maximize the utilization of space in the build chamber and reduce build time. However, the decision of these parameter is mainly dependant on the operators's experience. This paper presents the methodology to find the optimal build layout considering an orientation and packing of multiple parts in SLS processing. Each part is represented as a voxel structure to deal with the inefficiency in a bounding box approach. Test results show that the adapted BL algorithm with a genetic algorithm(GA) can be applicable to a real industry.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.5
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• pp.188-202
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• 2004

This research was designed to investigate biomechanical aspects of the evolution based on the hypothesis of dynamic cooperative interactions between the locomotion pattern and the body shape in the evolution of human bipedal walking The musculoskeletal model used in the computer simulation consisted of 12 rigid segments and 26 muscles. The nervous system was represented by 18 rhythmic pattern generators. The genetic algorithm was employed based on the natural selection theory to represent the evolutionary mechanism. Evolutionary strategy was assumed to minimize the cost function that is weighted sum of the energy consumption, the muscular fatigue and the load on the skeletal system. The simulation results showed that repeated manipulations of the genetic algorithm resulted in the change of body shape and locomotion pattern from those of chimpanzee to those of human. It was suggested that improving locomotive efficiency and the load on the musculoskeletal system are feasible factors driving the evolution of the human body shape and the bipedal locomotion pattern. The hypothetical evolution method employed in this study can be a new powerful tool for investigation of the evolution process.

• Animal cells and systems
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• v.7 no.1
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• pp.69-73
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• 2003

Serum lipid and lipoprotein levels are influenced by genetic factors, and exorcise increases the concentrations of cardio-protective parameters such as high-density lipoprotein cholesterol (HDL-cholesterol) and apolipoproteinAI (apoAI) in human serum. In the present study, we tested the effect of adaptation to endurance exercise on the association of a genetic polymorphism (Pst 1 RFLP) in the apoAI gene with these biochemical parameters. The genotype and allele frequencies for the Pst 1 RFLP were not significantly different between the elite athletes and sedentary controls (P>0.05). There were also no significant associations between the Pst 1 RFLP of the apoAI gene and the biochemical parameters in elite athletic group. Thus, our results suggest that the Pst 1 RFLP of the apoAI gene was not significantly associated with the serum apoAI and HDL-cholesterol concentrations as well as athletic performance in Koreans.

• International Journal of Oral Biology
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• v.47 no.2
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• pp.17-24
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• 2022

Preserving intact genetic material and delivering it to the next generation are the most significant tasks of living organisms. The integrity of DNA sequences is under constant threat from endogenous and exogenous factors. The accumulation of damaged or incompletely-repaired DNA can cause serious problems in cells, including cell death or cancer development. Various DNA damage detection systems and repair mechanisms have evolved at the cellular level. Although the mechanisms of these responses have been extensively studied, the global RNA expression profiles associated with genomic instability are not well-known. To detect global gene expression changes under different DNA damage and hypoxic conditions, we performed RNA-seq after treating human cervical cancer cells with ionizing radiation (IR), hydroxyurea, mitomycin C (MMC), or 1% O₂ (hypoxia). Results showed that the expression of 184-1037 genes was altered by each stimulus. We found that the expression of 51 genes changed under IR, MMC, and hypoxia. These findings revealed damage-specific genes that varied differently according to each stimulus and common genes that are universally altered in genetic instability.

• Animal Bioscience
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• v.36 no.2_spc
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• pp.374-384
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• 2023

Skeletal muscle metabolism regulates homeostatic balance in animals. The metabolic impact persists even after farm animal skeletal muscle is converted to edible meat through postmortem rigor mortis and aging. Muscle metabolites resulting from animal growth and postmortem storage have a significant impact on meat quality, including flavor and color. Metabolomics studies of postmortem muscle aging have identified metabolisms that contain signatures inherent to muscle properties and the altered metabolites by physiological adaptation, with glycolysis as the pivotal metabolism in postmortem aging. Metabolomics has also played a role in mining relevant postmortem metabolisms and pathways, such as the citrate cycle and mitochondrial metabolism. This leads to a deeper understanding of the mechanisms underlying the generation of key compounds that are associated with meat quality. Genetic background, feeding strategy, and muscle type primarily determine skeletal muscle properties in live animals and affect post-mortem muscle metabolism. With comprehensive metabolite detection, metabolomics is also beneficial for exploring biomarker candidates that could be useful to monitor meat production and predict the quality traits. The present review focuses on advances in farm animal muscle metabolomics, especially postmortem muscle metabolism associated with genetic factors and muscle type.

• Journal of Korean Society of Forest Science
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• v.97 no.2
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• pp.135-139
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• 2008

Seed production and germination could be influenced by some factors. The picking time and climate factors are regarded as the elements to obtain sound seeds. We have observed the seed productivity and germination of seeds from trees of Chamaecyparis obtusa selected in a clonal seed orchard. Depending on picking time, various shapes from liquid material, something jellied to the fully matured one were observed. Germination aspects varied throughout the test days. After 20days of seeding in a glass petri-dish, germinal apparatuses appeared from the all seeds which had been picked from after at the end of August. The highest germination rate of about 30% was observed from the seeds picked from $20^{th}$ of September and $10^{th}$ of October. Seed production was about two times higher in 2005 than in 2006 and the average germination rate was also higher in 2005. We have also analyzed the effects of climatic factors about two consecutive years on seed productivity. Among the climatic factors, monthly sum of temperature and of precipitation were the main factors for maturation of Chamaecyparis obtusa seeds.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.1-9
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• 2010

To protect information resources, many organizations including private corporate and government employ integrated information security systems which provide the functions of intrusion detection, firewall, and virus vaccine. So, in order to develop a reliable integrated information security system during the development life cycle, the managers in charge of the development of the system must effectively distribute the development resources to the quality factors of an integrated information security system. This study suggests a distribution methodology that minimizes the total cost with satisfying the minimum quality level of an integrated information security system by appropriately assigning development resources to quality factors considered. To achieve this goal, we identify quality factors of an integrated information system and then measure the relative weights among the quality factors using analytic hierarchy process (AHP). The suggested distribution methodology makes it possible to search an optimal solution which minimizes the total cost with satisfying the required quality levels of processes by assigning development resources to quality factors during the development life cycle.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.781-784
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• 2014

Background: Although the cause in most cases of childhood leukemia is not known, the contribution of environmental risk factors in the context of genetic predisposition has been reported with inconsistent results. The aim of this study was to examine association of childhood leukemia with maternal factors especially during pregnancy, to help in avoiding risk factors. Materials and Methods: This case-control study included children younger than 18 years diagnosed with leukemia from 2008 to 2012. Controls were randomly selected and individually matched to cases with respect to age, sex, and residency. All variables were compared between cases and control to determine any significant association with leukemia. Results: Statistically significant associations between risk of childhood leukemia with mother's education (p=0.001), occupation (p=0.0005) and pesticides exposure (p=0.005) during pregnancy were found. However, there were no significant links with maternal age (p=0.090), history of fetal loss (0.85), history of radiography during pregnancy (p=0.400), history of drug intake (p=0.689) and infection (p=0.696) during pregnancy. Conclusions: The results showed increased risk of leukemia in children whose mothers were working in agriculture and were exposed to pesticides during pregnancy. The further study needs to be investigated to know association of various maternal risk factors with leukemia which remained unknown in this study.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5077-5083
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• 2013

Background: Breast cancer is the most frequent cancer in women globally and represents the second leading cause of cancer death among women (after lung cancer). India is going through epidemiologic transition. It is reported that the incidence of breast cancer is rising rapidly as a result of changes in reproductive risk factors, dietary habits and increasing life expectancy, acting in concert with genetic factors. Materials and Methods: In order to understand the existing epidemiological correlates of breast cancer in South India, a systematic review of evidence available on epidemiologic correlates of breast cancer addressing incidence, prevalence, and associated factors like age, reproductive factors, cultural and religious factors was performed with specific focus on screening procedures in southern India. Results: An increase in breast cancer incidence due to various modifiable risk factors was noted, especially in women over 40 years of age, with late stage of presentation, lack of awareness about screening, costs, fear and stigma associated with the disease serving as major barriers for early presentation. Conclusions: Educational strategies should be aimed at modifying the life style, early planning of pregnancy, promoting breast feeding and physical activity. It is very important to obtain reliable data for planning policies, decision-making and setting up the priorities.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1677-1682
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• 2015

Cancer progression is attained by uncontrolled cell division and metastasis. Increase in tumor size triggers different vascular channel formation to address cell nutritional demands. These channels are responsible for transferring of nutrients and gaseous to the cancer cells. Cancer vascularization is regulated by numerous factors including vascular endothelial growth factors (VEGFs). These factors play an important role during embryonic development. Members included in this group are VEGFA, VEGFB, VEGFC, PIGF and VEGFD which markedly influence cellular growth and apoptosis. Being freely diffusible these proteins act in both autocrine and paracrine fashions. In this review, genetic characterization these molecules and their putative role in cancer staging has been elaborated. Prognostic significance of these molecules along with different stages of cancer has also been summarized. Brief outline of ongoing efforts to target hot spot target sites against these VEGFs and their cognate limitations for therapeutic implications are also highlighted.