• Korean Journal of Psychosomatic Medicine
• /
• v.24 no.2
• /
• pp.191-199
• /
• 2016

Objectives : Despite the increased popularity of highly caffeinated beverages, there is little research examining psychiatric adverse effects. The purpose of this study was to investigate the relationships among pattern of highly caffeinated beverage intake and depressive symptom, suicidal ideation, suicidal plan, suicidal attempt in Korean adolescents. Methods : The data was obtained from the 2014 Korean Youth's Risk Behavior Web-based Study by Korea Centers for Disease Control & Prevention. All participants conducted web-based questionnaire survey. Chisquare test and multiple logistic regression analysis were performed to determine the association among highly caffeinated beverage intake pattern, depressive symptom, suicidal ideation, suicidal plan and suicidal attempt adjusting for differences in age, gender, academic achievement, socioeconomic status. Results : A total of 71,638 participants were enrolled in this study. Depressive symptom, suicidal ideation, suicidal plan and suicidal attempt were significantly more frequent in the group with presence of highly caffeinated beverage intake within 1 week than in non-drinker group(p<0.01). Highly caffeinated beverage intake was significantly associated with suicidal attempt(OR=1.99 ; 95% CI, 1.77-2.22). In addition, depressive symptom, suicidal ideation, suicidal plan and suicidal attempt were significantly more common in the group with heavy-drinker who exceed recommended daily intake dose of caffeine than in the group with light-drinker(p<0.01). Heavy drinking of caffeinated beverage was significantly associated with suicidal attempt(OR=4.05 ; 95% CI, 3.02-5.43). Conclusions : We found that highly caffeinated beverage intake was related to more frequent depressive symptom, suicidal ideation, plan, attempt in adolescents. Also, caffeine intake which exceed recommended daily intake dose identified the predictor of suicidal attempt. Our result suggested that clinicians need to be aware of the possible psychiatric adverse effects of highly caffeinated beverage in vulnerable population including young adolescents.

• Korean Journal of Labor Studies
• /
• v.17 no.1
• /
• pp.139-176
• /
• 2011

Non-regular workers came to the fore while working class formation was in retreat along with the democratic labor movement of regular workers. The formation of principal agents, however, is yet to occur. Then, why non-regular workers' struggles could not yield a consequence in that regard? What kind of factors are to determine the outcome of the struggles and how do they do it? It is the aim of this study to answer those questions. In contrast with regular workers' struggles, non-regular workers' struggles tend to break out in response to capitalist offensives, rely on atypical and, often, extreme measures of struggle rather than strike in the form of work stoppage, drag out for too long, and appeal for social solidarity outside when the solidarity of regular workers is not available. Non-regular workers' struggles tend to end up with failure rather than success, and with weakening rather than strengthening of their organizational strength. So as to overcome the tendency to fail, non-regular workers' struggles need regular workers' solidarity in addition to their own strong mobilization power, while social solidarity or positional power could substitute for regular workers' solidarity in some cases. So as to build up their organizational strength, non-regular workers' struggles should win victories in the struggles, while a victory could turn into a trap in the case of conversion. Both regular workers' solidarity and the internal integration of the struggles are two foremost important factors in achieving the victory of struggles and the building-up of organizational strength. Those who have got involved in struggles are from the best organized sector among all the non-regular workers. As they have gone through weakening of organizational strength, it becomes more difficult for non-regular workers to form principal agents. Without non-regular workers' struggles, however, the capitalist offensives must have carried the day. In that sense, non-regular workers' struggles did a role in at least detaining capitalist offensives, if not stopping them. The practical implication of non-regular workers' struggles is that, if non-regular workers redefine the ultimate goal of their struggles as the formation of their principal agents for working class formation, it would be a strategically rational choice to identify the strategic objective of struggles with the maintaining and strengthening of their organizational strength rather than the achievement of their immediate demands.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.32 no.3
• /
• pp.218-228
• /
• 2010

Components of dental resin-based restorative materials are reported to leach from the filling materials even after polymerization. Hydroquinone (HQ) is one of the major monomers used in the dental resin and is known as a carcinogen. Thus, carcinogenic risk of HQ leaching from the dental resin becomes a public health concern. The present study attempted to examine the carcinogenic potentials of HQ on the human epithelial cell, which is the target cell origin of the most of oral cancers. Cytotoxicity of HQ was observed above 50${\mu}M$ as measured by LDH assay, indicating a relatively low toxicity of this substance in human epithelial cells. The parameters of neoplastic cellular transformation such as cell saturation density, soft agar colony formation and cell aggregation were analyzed to examine the carcinogenic potential of HQ. The study showed that 2-week exposure of HQ showed the tendency of increase in the saturation density and the significant enhancement of soft agar colony formation at the highest dose, 50 ${\mu}M$ only. It is suggested that HQ has a weak potential of carcinogenicity. When cells were treated with HQ and TPA, a well-known tumor promoter, the parameters of neoplastic cellular transformation was significantly increased. This result indicates that the potential risk of carcinogenicity from HQ is largely dependent upon the presence of promoter. Exposure of 50 ${\mu}M$ HQ increased the time-dependent apoptosis as measured by the ELISA kit. This concentration coincides with a dose of neoplastic transformation, indicating a possible link between apoptosis and HQ-induced cellular transformation. Hydroquinone generated Reactive Oxygen Species (ROS) which was evidenced by the treatment of antioxidants such as trolox and N-acetyl cysteine and the GSH depleting agent, BSO. Antioxidants blocked the generation of ROS and the GSH depleting agent, BSO dramatically increased the ROS production. Since HQ is known to increase ROS production thru activation of transcriptional factor such as c-Myb and Pim-1, it is speculated that ROS generation by HQ plays a role in the activation of oncogene, which may lead to neoplastic transformation. In addition, ROS is involved in the alteration of signal transduction, which regulates the apoptosis in many cellular systems. Thus, ROS-mediated apoptosis may be involved in the HQ-induced carcinogenic processes. Protein kinase C (PKC) is known to play pivotal roles in neoplastic transformation of cells and its high expression is often found in a variety of types of tumors including oral cancer. PKC translocation of PKC-${\alpha}$ was observed following HQ exposure. Altered signaling system may also play a role in the transformation process. Taken together, HQ leached from the dental resin does not pose a significant threat as a cancer causing agent, but its carcinogenic potential can be significantly elevated in the presence of promoter. The mechanism of HQ-induced carcinogenesis involved ROS generation, apoptosis and altered signaling pathway. The present study will provide a valuable data to estimate the potential risk of HQ as a carcinogen and understand mechanism of HQ-induced carcinogenesis in human epithelial cells.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.5
• /
• pp.673-681
• /
• 2011

We investigated the effects of an ethanol extract of Eriobotrya japonica Lindl. (loquat) leaves (EJ) on the lipid metabolism of serum, liver, and adipose tissue, and antioxidative activity in rats fed a fat/cholesterol diet for four weeks. Male Sprague-Dawley rats weighing 207 g were divided into 4 groups: a normal diet group (N), a high-fat/high-cholesterol diet group (HFC), a high-fat/high-cholesterol diet group administered 200 mg/kg day EJ (HFC-EJL), and a high-fat/high-cholesterol diet group administered 400 mg/kg/day EJ (HFC-EJH). The serum ALT and AST activities of the EJ groups were lower than those of HFC group, but there was no significant change in serum ALP or LDH activities. The serum total and LDL-cholesterol, atherogenic index, and cardiac risk factor tended to be decreased in the EJ groups compared to the HFC group, while the serum HDL-cholesterol decreased in the HFC group and increased only minimally in the EJ groups. The total cholesterol in liver and mesenteric adipose tissues was lower in the EJ groups than in the HFC group. Triglycerides in the mesenteric and epididymal adipose tissues were lower in the EJ groups than in the HFC group. The liver GSH levels of the EJ groups were significantly lower than the HFC group. The liver TBARS content was significantly lower in the EJ groups than in the HFC group. These results suggest that EJ ethanol extract may improve the lipid metabolism of serum, liver, and adipose tissue and prevent oxidative stress by stimulating antioxidative systems in rats fed a high-fat/high-cholesterol diet.

• Journal of Digital Convergence
• /
• v.10 no.9
• /
• pp.195-212
• /
• 2012

Most of the office-workers are worrying about their future and try to make diverse future plan. Fast shifting industry pattern make office-workers retire early and their remain life time are getting longer and many of them try to consider some kind of new start-up. In this article factors affecting entrepreneurial intention were discussed such as individual factors, psychological factors, environmental factors. Individual factors were economic situations and future life expectation were analyzed. Psychological factors were composed of risk taking tendency, self efficiency, career value, and entrepreneurial characteristics were discussed. Environmental factors were composed of recognition on social-economic risks and recognition on negative mind on start-up, and employment unstability. 340 sample questionaries were collected and 26 samples were excluded. Data were analyzed by SPSS Win 18.0 Version. The results of the study were as follows. Among individual factors life-expectation after retirement was positive impact on entrepreneurial intention. Among psychological factors risk taking factor has positive impact on entrepreneurial intention. Among Environmental factors negative recognition on start-up has negative impact on entrepreneurial intention. Based on the studies diverse understanding and implementation of policies were necessary to change negative social atmospheres on start-up.

• Journal of Navigation and Port Research
• /
• v.39 no.3
• /
• pp.267-275
• /
• 2015

Port Logistics Industry plays a crucial role in trade creating added value, and contributes greatly in economic growth of a nation. Multitude of studies have been conducted to develop this industry as a means of intensifying national competitiveness. In line with this trend, this study aims to examine the effect of the Port Logistics Industry on the regional economy focusing on Ulsan, and also compare the industry among five port cities by using Korean Standard Industrial Classification (KSIC) Rev. 9 and 2010 Economy Census. The results of this study demonstrate that the Port Logistics Industry has significant regional employment rate and economic importance, showing the high number of workers (11.7%) and sales (13.1%) in 2010. According to the comparison among five port cities between 2007 and 2011, the increase of annual average in the number of companies of Gwangyang (5.72%) and Ulsan (4.23%) is higher than the national average (1.74%), and Ulsan (23.82%) and Pyeongtaek (25.74%) show high increase of annual average in the number of workers.

• Journal of Navigation and Port Research
• /
• v.30 no.8 s.114
• /
• pp.643-648
• /
• 2006

The primary purpose of this study is to examine empirically the effect of foreign crew's cultural and organizational characteristics on their self-efficacy and organization commitment. Currently, the restrictions on the employment of the foreign crews are being eased in the Korean shipping industry and many problems are occurring consequently. However, specific and empirical studies on the relevancy of cultural characteristics to the crew's self-efficacy and organizational commitment on board the vessels with combined crews have not yet been carried out. To solve these problems, we examined how the cultural characteristics such as acculturation and accommodation of different culture related to the improvement of cultural homogeneity of vessels with combined crews influence on the self-efficacy, job satisfaction and organizational commitment of the foreign crews through SEM analysis. According to the results, hypothesis 1 and 2 were all supported with statistical significance. To conclude, this study suggests that foreign crew's cultural homogeneity and their self-efficacy should be firstly enhanced in order to improve organizational commitment on the vessel with combined crews. Furthermore, a study on self-efficacy of crew organization is urgently needed to enhance the effectiveness of an organization in a vessel with combined crews that has special environment. The result of this study will contribute a lot to the organization management of a vessel with combined crews.

• Korean Journal of Childcare and Education
• /
• v.7 no.1
• /
• pp.41-65
• /
• 2011

The purpose of this study was to examine the influence of satisfaction with workplace child-care on the parenting stress, job commitment, and job satisfaction of parents. The questionnaires survey of this study was conducted on 185 parent-employees (97 fathers & 88 mothers) who used employer-supported child-care in the province of Kyungki-do. The results of this study were as follows: As the level of satisfaction with workplace child-care became higher, the level of parenting stress became lower. And as the level of satisfaction with workplace child-care became higher, the level of job commitment and job satisfaction became higher. Among five components of satisfaction with workplace child-care, satisfaction with the environment for child-care had an independent influence on parenting stress. And satisfaction with the management of child-care facility had an independent influence on job commitment and job satisfaction. This study suggested that education programs that target employers need to raise employers' awareness about the importance of workplace child-care in order to reduce parenting stress and to enhance job commitment and job satisfaction of parent-employees.

• Korean Journal of Social Welfare
• /
• v.68 no.4
• /
• pp.97-118
• /
• 2016

The primary goal of this study was to investigate factors affecting job satisfaction of injured workers who returned to work. There are two types of injured workers' returning to work returning to pre-injury job and getting a new job. After separating the two types of workers we conducted the multiple regression analysis on the data from the Workers'Compensation Insurance Panel of the Korea Workers' Compensation and Welfare Service Corporation(2014). The sample consisted of 1,333 occupationally injured workers who were finished with medical treatment(693 workers returned to previous work place, and 640 workers found new work places). Main results are as follows. First, injured workers who got new jobs were vulnerable to sustainability to job, work status, average monthly wage as well as job satisfaction compared with injured workers who returned to pre-injury job. Second, gender, educational level, skill fitness, average monthly wage, welfare benefits, family income/leisure life/residential environment/social relation satisfaction, and maintenance of relation with business owner during medical care were related to job satisfaction of injured workers who returned to pre-injury job. Third, gender, work status, skill fitness, continuous work possibility, average monthly wage, family income/leisure life/social relation satisfaction, substitute worker for assigned task during medical care and maintenance of relation with business owner during medical care affected on job satisfaction of injured workers who got new jobs. Based on these findings implications for policy and interventions were discussed in regards to job satisfaction of injured workers.

• Korean Journal of Social Welfare
• /
• v.57 no.2
• /
• pp.375-403
• /
• 2005

This Study reviews theoretical argument about the effect of retirement earnings test on the labor supply of the aged which is controversial issue in OECD countries and analyze the effect on the incidence of re-employment, re-employment period of suspended officials and the possibility of re-retirement through Government Employment Pension Corporation data. It consists of 178,363 public officials who received pension benefit or disability pension in January 2005. The main result of this research shows that public officials re-employed were 8,086 which is 4.5% of total retired, and median survival time of suspended pension payments is 3.3 years. Also the median re-employment period of 100% suspended officials is about 20 month shorter than that of 1/2 suspended officials and it is shown in regression analysis that the possibility of re-retirement by 100% suspended officials is statistically significant higher than those of 50%. It specially expects greater influence if includes in case taking lump-sum or no making effect of re-employment because current system withhold pension payments even by earned income itself. Therefore, this analysis suggests suspension of pension payment properly applied according to the age and income together with "Delayed Retirement Credit" or "Partial Pension" for developmental alternatives of civil servant's suspension of pension payments. Furthermore, It is urgently needed that distinctive quality data about re-employment including earnings to perform deep-empirical research for effective policy. Lastly, it is extremely necessary to reinforce management system of Government Employment Pension Corporation.