• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4517-4525
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• 2016

Background: Sperm DNA damage is underlying aetiology of poor implantation and pregnancy rates but also affects health of offspring and may also result in denovo mutations in germ line and post fertilization. This may result in complex diseases, polygenic disorders and childhood cancers. Childhood cancer like retinoblastoma (RB) is more prevalent in developing countries and the incidence of RB has increased more than three fold in India in the last decade. Recent studies have documented increased incidence of cancers in children born to fathers who consume alcohol in excess and tobacco or who were conceived by assisted conception. The aetiology of childhood cancer and increased disease burden in these children is lin ked to oxidative stress (OS) and oxidative DNA damage( ODD) in sperm of their fathers. Though several antioxidants are in use to combat oxidative stress, the effect of majority of these formulations on DNA is not known. Yoga and meditation cause significant decline in OS and ODD and aid in regulating OS levels such that reactive oxygen speues meditated signal transduction, gene expression and several other physiological functions are not disrupted. Thus, this study aimed to analyze sperm ODD as a possible etiological factor in childhood cancer and role of simple life style interventions like yoga and meditation in significantly decreasing seminal oxidative stress and oxidative DNA damage and thereby decreasing incidence of childhood cancers. Materials and Methods: A total of 131 fathers of children with RB (non-familial sporadic heritable) and 50 controls (fathers of healthy children) were recruited at a tertiary center in India. Sperm parameters as per WHO 2010 guidelines and reactive oxygen species (ROS), DNA fragmentation index (DFI), 8-hydroxy-2'-deoxy guanosine (8-OHdG) and telomere length were estimated at day 0, and after 3 and 6 months of intervention. We also examined the compliance with yoga and meditation practice and smoking status at each follow-up. Results: The seminal mean ROS levels (p<0.05), sperm DFI (p<0.001), 8-OHdG (p<0.01) levels were significantly higher in fathers of children with RB, as compared to controls and the relative mean telomere length in the sperm was shorter. Levels of ROS were significantly reduced in tobacco users (p<0.05) as well as in alcoholics (p<0.05) after intervention. DFI reduced significantly (p<0.05) after 6 months of yoga and meditation practice in all groups. The levels of oxidative DNA damage marker 8-OHdG were reduced significantly after 3 months (p<0.05) and 6 months (p<0.05) of practice. Conclusions: Our results suggest that OS and ODD DNA may contribute to the development of childhood cancer. This may be due to accumulation of oxidized mutagenic base 8OHdG, and elevated MDA levels which results in MDA dimers which are also mutagenic, aberrant methylation pattern, altered gene expression which affect cell proliferation and survival through activation of transcription factors. Increased mt DNA mutations and aberrant repair of mt and nuclear DNA due to highly truncatred DNA repair mechanisms all contribute to sperm genome hypermutability and persistant oxidative DNA damage. Oxidative stress is also associated with genome wide hypomethylation, telomere shortening and mitochondrial dysfunction leading to genome hypermutability and instability. To the best of our knowledge, this is the first study to report decline in OS and ODD and improvement in sperm DNA integrity following adoption of meditation and yoga based life style modification.This may reduce disease burden in next generation and reduce incidence of childhood cancers.

• Journal of dental hygiene science
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• v.11 no.5
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• pp.389-395
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• 2011

The purpose of this study was to examine dental hygiene students' achievement motivation and factors affecting dental hygiene students' achievement motivation by the general characteristics of subjects in this study. The subjects in this study were 450 who were selected by convenience sampling from three different three-year-course colleges. After a survey was conducted, the answer sheets from 421 respondents were analyzed. The collected data were analyzed, which made use of t-test, ANOVA and Kruscal-Wallis test. The findings of the study were as follows. 1. The dental hygiene students investigated got 3.34 in achievement motivation. They got the highest score of 3.78 in the item 'I perform what I have to do with a sense of responsibility.' and they got the lowest score of 2.67 in the item 'I like to do something risky.' 2. Concerning links between their general characteristics and achievement motivation, the students whose academic year was higher(p<0.001) and who had more clinical practice experiences (p<0.01) were better motivated than their counterparts. As to connections between achievement motivation and expected post-graduation length of service, those who replied that they planned to find another job after getting married were better motivated(p<0.05). Regarding relationship between achievement motivation and a will to work abroad, the students who had a stronger will to work abroad were better motivated. 3. As a result of checking the influence of their general characteristics on achievement motivation, stronger motivation was found among the students whose academic year was higher(p<0.01), who intended to work until marriage(p<0.01) and who didn't plan to keep working after marriage(p<0.05) when the other variables were controlled. Therefore dental hygiene students should be taught to look at things positively when they enter college, and they should also be educated to become progressive to keep working for their lifetime instead of just getting a temporary job after graduation.

• Journal of dental hygiene science
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• v.13 no.1
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• pp.36-44
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• 2013

The purpose of this study was to provide basic data for healthy and effective dental management by providing the knowledge and information on periodontal health promotion as well as high dental health interests, by doing a comparative analysis of the effect of dental health knowledge and oral hygiene management skills of people in their 20s on periodontal health status assessment, to find periodontal disease early and prevent it targeting 130 adults in their 20s who visited dental hygienic lab for comprehensive dental hygiene care and treatment from September 25 to October 30. The data collected used SPSS 18.0. To present the technical characteristics of the data, frequency was used and chi-squared test through cross-analysis was conducted to investigate dental health knowledge and the relevance between the variables of oral hygiene management skills of general characteristics. To examine periodontal health status assessment, t-test and One-way ANOVA and Turkey post-hoc tests were carried out at the 5% significance level. Regression analysis was performed to investigate the impact of dental health knowledge and oral hygiene management skills on dental health status assessment. As a result of this study, as dental health knowledge on tooth brushing of people in their 20s increased, plaque index reduced, as dental health knowledge on periodontal disease increased, plaque index reduced. Dental health status assessment according to a total number of times tooth brushing, tooth brushing methods, whether to use dental hygiene devices, smoking status, drinking frequency per week, whether to have oral health education was statistically significant. To improve the level of dental health knowledge and oral hygiene management skills, oral health education should be strengthened as well as the publicity through the media to have the information on oral health and learn it.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.227-231
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• 2010

Slurry composting biofiltration(SCB) is considered as a treatment to produce a better fertilizer resource than raw pig slurry as it reduces odor and improves nutrients imbalance. For the agricultural use of SCB slurry as a nutrient source with minimum environmental impact, it is important to investigate the effect of different rate of SCB slurry application on nutrient (particularly for nitrogen) uptake and growth of crops. This study was conducted to investigate the influence of fertigation using pig slurry(PS) on growth and yield of red pepper and to evaluate the appropriate PS concentration in fertigation for soils with different nitrate concentration. To evaluate the effects of fertigation applied PS as a substitute of chemical fertilizer(CF), a single application of three different concentrations of PS: $N_{0.5}$ (43 mg/L), $N_{1.0}$ (86 mg/L) and $N_{1.5}$ (131 mg/L) were compared with CF $N_{1.0}$ (89 mg/L) as a control nitrogen fertilizer. Statistical analysis showed that the growths of red pepper were not affected by treatments. In addition, the yields were no significant difference among treatments, though the highest yield was obtained in PS $N_{1.0}$ by 20,580 kg/ha. In soil chemical properties, nitrate nitrogen on soil of between PS N1.0 and CF $N_{1.0}$ treatment showed similar patterns although they were higher than the preplant nitrogen content. Also, there was no significant difference in yield of red pepper between PS and CF treatment applied as fertigation on soils where nitrate nitrogen contents of each soil contains 10, 100 and 200 mg/kg respectively. Consequently, the application of PS, such as SCB, as a substitute of CF is available for growth and yield of red pepper, there could be accordingly estimated the optimal fertigation concentration of PS for red pepper cultivation.

• Proceedings of the KOR-KST Conference
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• 1995.02a
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• pp.3-32
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• 1995

The Highway Capacity Manual specifies procedures for evaluating intersection performance in terms of delay per vehicle. What is lacking in the current methodology is a comparable quantitative procedure for ass~ssing the safety-based level of service provided to motorists. The objective of the research described herein was to develop a computational procedure for evaluating the safety-based level of service of signalized intersections based on the relative hazard of alternative intersection designs and signal timing plans. Conflict opportunity models were developed for those crossing, diverging, and stopping maneuvers which are associated with left-turn and rear-end accidents. Safety¬based level-of-service criteria were then developed based on the distribution of conflict opportunities computed from the developed models. A case study evaluation of the level of service analysis methodology revealed that the developed safety-based criteria were not as sensitive to changes in prevailing traffic, roadway, and signal timing conditions as the traditional delay-based measure. However, the methodology did permit a quantitative assessment of the trade-off between delay reduction and safety improvement. The Highway Capacity Manual (HCM) specifies procedures for evaluating intersection performance in terms of a wide variety of prevailing conditions such as traffic composition, intersection geometry, traffic volumes, and signal timing (1). At the present time, however, performance is only measured in terms of delay per vehicle. This is a parameter which is widely accepted as a meaningful and useful indicator of the efficiency with which an intersection is serving traffic needs. What is lacking in the current methodology is a comparable quantitative procedure for assessing the safety-based level of service provided to motorists. For example, it is well¬known that the change from permissive to protected left-turn phasing can reduce left-turn accident frequency. However, the HCM only permits a quantitative assessment of the impact of this alternative phasing arrangement on vehicle delay. It is left to the engineer or planner to subjectively judge the level of safety benefits, and to evaluate the trade-off between the efficiency and safety consequences of the alternative phasing plans. Numerous examples of other geometric design and signal timing improvements could also be given. At present, the principal methods available to the practitioner for evaluating the relative safety at signalized intersections are: a) the application of engineering judgement, b) accident analyses, and c) traffic conflicts analysis. Reliance on engineering judgement has obvious limitations, especially when placed in the context of the elaborate HCM procedures for calculating delay. Accident analyses generally require some type of before-after comparison, either for the case study intersection or for a large set of similar intersections. In e.ither situation, there are problems associated with compensating for regression-to-the-mean phenomena (2), as well as obtaining an adequate sample size. Research has also pointed to potential bias caused by the way in which exposure to accidents is measured (3, 4). Because of the problems associated with traditional accident analyses, some have promoted the use of tqe traffic conflicts technique (5). However, this procedure also has shortcomings in that it.requires extensive field data collection and trained observers to identify the different types of conflicts occurring in the field. The objective of the research described herein was to develop a computational procedure for evaluating the safety-based level of service of signalized intersections that would be compatible and consistent with that presently found in the HCM for evaluating efficiency-based level of service as measured by delay per vehicle (6). The intent was not to develop a new set of accident prediction models, but to design a methodology to quantitatively predict the relative hazard of alternative intersection designs and signal timing plans.

• Journal of the Korean Wood Science and Technology
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• v.17 no.1
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• pp.3-11
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• 1989

This study was carried out to investigate the physical and mechanical properties. durability of adhesive bond and paint film for the basic data which were required to determine the suitability as a raw material for furniture the laminated veneer lumber (LVL) with pitch pine (Pinus rigida Mill). The results obtained were as follows; 1) The proper pressing time for making the LVL was over 45 second per milimeter of LVL thickness. 2) The bending strength of the LVL was lower than that of the solid wood but the compressive strength of the LVL was similar to that of the solid wood. The strength increased with the decrease of veneer thickness. 3) The impact bending absorbed energy of the LVL was 0 to 0.3 kg.m/$cm^2$ in the direction of parallel to the grain. The energy of the LVL was lower than that of the solid wood (0.68 kg.m/$cm^2$). 4) In warm water soaking and cold-dry tests, delamination of adhered layers surface crack, swelling, and color change were not found when the hot pressing time was over 45 second per milimeter of LVL thickness. As a result of soak under vacuum test shrinkage in the direction of parallel to the grain was about -1.0 percent and. was about 3.0 percent in the direction of the perpendicular to the grain. 6) The film cacks on the LVL's surface after the wet and cold-dry test were not found at all. 7) In the use of the LVL for interior decoration it was considered that the surface of the LVL be overlaid crossly with fancy veneers of birch and paulownia, etc. This cross overlayirg methods have resulted in few cracks on the fancy veneer.

• Journal of the Korean Geographical Society
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• v.29 no.3
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• pp.318-339
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• 1994

U.S. had given large amount of cotton to Korea as food aid program since 1945. This cotton aid had negative impact on cotton culture in Korean agriculture. Korean government used counterparts funds (sale proceeds of food aid) not for investment to agriculture sector, but for military budgets. And food aid on program type had influenced general economic policies, which neglected agricultural sector too. Anti-agricultural policy which was helped by U.S. food aid, had caused cotton cultivator an economic loss. So this economic loss had made many farmers abandon cotton culture. But in our times, cotton is cultivated for the purpose of domestic consumption in a few rural villages. The purposes of this study are 1) to analyze the process of spatial reduction of cotton culture since 1945 in regional contexts in Korea, and 2) to identify the function and meaning of cotton culture which does not pay off in agricultural region. Materials for acreage of cotton culture are acquired through the agricultural statistical year book(1952-1989) and census. To clarify the meanings of cotton culture, field survey are conducted in a rural village which is identified as only one where cotton was cultivated in 1993. In these contexts, this study has come to the following conclusions. In the period of under the rule of Japanese Imperialism (1910-1945), G. arboreum, species of cotton which was traditionally cultivated since 1364, had been driven out. And G. hirustun species, which is suitable for the production of highly qualified textile, has been hierarchically diffused by policy. In these period, regional structure of Korean agriculture was reorganized for the provision with food to Japan. Crops leading this dependent spatial structure were rice and cotton. So agricultural region, specialized with cotton, were distributed in the hinterland of the area which is specialized with rice. U.S. cotton aid to Korea began in 1947. U.S. took an interest in agricultural export because of her domestic surplus of cotton. Cotton aid is one mechanism by which U.S government developed agricultural market in recipient countries, Specially in the exchange rates, up-valuation of won to the U.S. dollars made domestic cotton more expensive than cotton imported, Production cost of domestic cotton is higher than Government's purchasing price of cotton which was also more expensive than price of cotton imported. Korean farmer could not help abandoning the cultivation of cotton, and this gave rise to spatial reduction of cotton culture. Spatially, cotton culture was abandoned in early stage of reduction in regions where stand at a disadvantage climatically, and in next stage in regions where other up-land crops which paid off in urban market, eg, fruits, could be cultivated. In the stage of extinction, cotton was cultivated only in area where G. hirustun species was originated in Korean peninsula. This region is not only suitable climatically for cotton culture, but is far away from urban market. Use of cotton produced is not for spinning, but for fillings of comforter. The main purpose of cotton culture in rural village is not for cotton yields, but for increase of production of seasame, which is grown together with cotton as mixed crops. Cotton product are used for domestic consumption and sold out to gin house. Though cotton culture is not paid off, farmer wanted to cultivate continuously for the cultural purpose, and they wanted the cotton culture promotion policy with the goverment subsidy.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.6
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• pp.1-9
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• 2016

In this study, we investigate the announcement effects of M&As with a start-up as a target firm on shareholder wealth of an acquiring firm. We use M&A events in KOSPI or KOSDAQ market between 2002 and 2014 after the financial crisis. Among the total 1436 mergers and acquisitions that took place domestically during this period, 1383 cases were selected as cases to be studied, excluding 53 cases where acquiring firms were unlisted firms. The results of the analysis are as follows: First, as a result of a comparison between the acquiring firms' CARs of the whole sample group(n=1383) occurred during the (-2, +1), (-5, +2), (-10, +5) periods of M&A announcement date(t=0) and the sub-sample group(n=468) where the target firms are start-ups which were established within five years, the acquiring firms of the whole sample group do not show significat CARs, while the acquiring firms of the sub-sample group show the significantly positive CARs. This suggests that M&A with start-ups have a positive effect on firm value of acquiring firms. Second, when merging unlisted start-ups, the acquiring firms show positive CARs, showing that there exists a listing effect in the merger of start-up. Third, merging the start-ups belonging to the high-tech industry shows the higher CARs than the case of merging the start-ups belonging to the non-high-tech industry. This study has great significance as the first in Korea to investigate the effect of M&A announcement with a start-up.

• Journal of Distribution Science
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• v.9 no.1
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• pp.39-48
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• 2011

One of the major reasons for fierce competition among firms is that they strive to increase their own market shares in the same market with similar and apparently undifferentiated products in terms of quality and perceived benefit. Due to such changes in the marketing environment, differentiated after-sales service and diversified promotion strategies have become more important in the race to gain a competitive advantage. Price discount is one of the popular promotion strategies that most retailers use, especially to increase sales, but offering a price discount does not always lead to the expected result. If marketers apply an identical price-promotion strategy without considering the characteristic differences in products and consumer preferences, the discounted price itself may make people skeptical about the quality of the product. Moreover, the changes in perceived value may appear differently depending on factors such as consumer involvement. This implies that variables such as the level of consumer involvement, brand loyalty, and external reference prices, in reality, would have different effects on how consumers perceive the value of price discounts. The variables that affect consumers' perceived values and buying decisions are diverse and complicated. Several studies have examined the effects of such variables as external reference price, selling price, and brand on consumers' perceived value of products. Results have not shown consistent patterns. Therefore, we must note that the factors affecting consumers' value perceptions and buying behaviors are diverse and that the results of studies on the same dependent variable come out differently depending on what that variable is. This study focused on the level of consumer involvement as a salient variable that supposedly affects the perceived value of a product, willingness to buy, and search intentions. We tried to examine whether a price discount affects the perceived value-such as perceived acquisition value and perceived transaction value-in different ways depending on the level of consumer involvement. In addition, we proposed managerial implications that marketers need to consider as a whole, for instance, product attributes, brand loyalty, and involvement and then established a differentiated pricing strategy, case by case, in order to effectively enhance consumers' perceived values. As a result, we found that perceived transaction value positively affects perceived acquisition value and when discounting the price of a high-involvement product enhances the consumer's willingness to buy, but perceived acquisition value does not affect the search intentions significantly. In the case of discounting prices of low-involvement products, on the other hand, the perceived transaction value has a positive effect on the willingness to buy, but the negative effect of perceived acquisition value on the search intentions was not significant. We suppose that people doubt a product's quality because of a declined perceived quality derived from a price discount. Even though the price discount enhanced the transaction value, people eventually increased their level of searching for additional product information. From the results of this study, we suggest that marketers ought to establish an appropriate value-enhancing strategy based on the understanding of which perceived value consumers rely on more when they conduct purchasing behavior because consumers perceive the degree of importance of acquisition value or transaction value differently, depending on their level of involvement.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.3
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• pp.223-231
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• 2020

Governments and private companies have established various local entrepreneurial infrastructure institutions in most regions in order to reduce youth unemployment, and boost youth entrepreneurship and regional employment. However, previous studies has been limited to explore the impact of the entrepreneurial infrastructure institutions on the willingness of start-up entrepreneurs. Thus, the main purpose of this study is to fill in the gaps of the research, identify the effect of the entrepreneurial infrastructure institutions on regional employment focusing on the Partner Squares which are entrepreneurial infrastructure institutions in several regions and established by N company, and set a foundation for further research regarding the effectiveness of the entrepreneurial infrastructure institutions. In order to verify the effectiveness of the Partner Squares on the local employment, we use the raw data of the Economically Active Population Survey (Statistics Korea) and analyze the effectiveness by using the Difference-in-Differences model. The main findings are as follows. While the Partner Square Seoul has not statistically influenced on the employment of local youth workers, the Partner Square Busan has increased about 3% of the average number of employees (575 thousand) from May 2017 to July 2019, increasing the number of local youth workers by 17,000. Also, after the establishment of the Partner Square Gwangju, the institution has increased 4,500 local employees, which is about 1.7% of the average number of employees (267,000) from September 2018 to July 2019. This implies that the Partner Squares provide a variety of effective start-up education programs and networks for pre-starters and founders in the region, thereby helping them to grow and boosting the local employment. An important implication is that by using government statistical data, we find roles of entrepreneurial infrastructure institutions to revitalize local economy and employment. In future studies, studies need to be conducted considering various exogenous variables that can affect local employment, such as the government industrial policies and entrepreneurial infrastructure institutions other than the Partner Squares.