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Chlorine (Cl)-containing chemicals, including hydrogen chloride, generated during thermal degradation of polyvinyl chloride (PVC) and corresponding mixture impede the chemical recycling of PVC-containing plastic wastes. While upgrading plastic-derived vapors, the presence of Cl-containing chemicals may deactivate the catalysts. Accordingly, herein, catalytic upgrading of pyrolysis vapor prepared from a mixture of PVC and polyolefins is performed using a fixed-bed reactor comprising zeolites. Among the H-forms of zeolites (namely, ZSM-5, Y, β, and chabazite) used in this study, a higher yield of gas products composed of hydrocarbons with lower carbon numbers is obtained using H-ZSM-5, thus indicating further decomposition of the pyrolysis vapor to C 1 -C 4 hydrocarbons on it. Although the formation of aromatic compounds is better on H-ZSM-5, product distributions can be adjusted by further modifying the acidic properties via the alteration of the Si/Al molar ratio, and maximum yields of C 1 -C 4 compounds (60.8%) and olefins (64.7%) are achieved using a Si/Al molar ratio of 50. Additionally, metal ion exchange on H-ZSM-5 is conducted, and upgrading of PVC-containing waste-derived vapor to aromatic chemicals and small hydrocarbon molecules was successfully performed using Co-substituted H-ZSM-5. It reveals that the highest yield of gas products on 1.74 wt% cobalt (Co)-substituted H-ZSM-5 is acquired via the selection of an appropriate metal and metal ion concentration adjustment. Nevertheless, introduction of excess Co into the H-ZSM-5 surface decreases the cracking activity, thereby implying that highly distributed Co is required to achieve excellent cracking activity. The addition of Co also adjusted the acid types of H-ZSM-5, and more Lewis acid sites compared to Brønsted acid sites selectively produced olefins and naphthenes over paraffins and aromatics. The proposed approach can be a feasible process to produce valuable petroleum-replacing chemicals from Cl-containing mixed plastic wastes, contributing to the closed loops for upcycling plastic wastes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background and Objectives : Metabolic syndrome is a growing health concern globally, and its prevalence continues to increase. This study investigated whether a marine healing program could improve metabolic syndrome indicators and mental health in adults with a metabolic syndrome and those at risk of developing it. Materials and Methods : This study enrolled 30 participants who were assigned to either the experimental or control groups. The duration of the study was set at 4 weeks. Both groups received metabolic syndrome management education, and the experimental group additionally participated in two marine healing programs. Anthropometric indicators, biochemical indicators, and mental health indicators were collected before and after the intervention. Results : The findings indicate that the experimental group had significantly lower systolic blood pressure, triglycerides, and body weight, as well as higher levels of high-density lipoprotein (HDL-C) and uric acid. Mental health indicators (Hospital Anxiety and Depression Scale and quality of life measures) additionally showed improvement. Pre-post comparisons between the experimental group and the control group showed that the experimental group had significantly decreased by 1.05 kg in body weight, whereas the control group increased by 0.29 kg in body weight. In addition, HDL-C decreased by 0.91 mg/dL in the control group and increased by 3.7 mg/dL in the experimental group. Conclusions : Overall, these results suggest that marine healing programs could improve metabolic syndrome indicators such as body weight and HDL-C better than the control treatment.

Endophytic fungi occupy inner plant tissues, which results in various interactions between the fungus and host. Studies on endophytic fungi have been conducted in Korea for over 30 years. This paper summarizes the published results of those studies. The endophytic fungi of approximately 132 plant species in Korea have been studied since the 1990s, resulting in over 118 publications. The host plants featured in these studies comprised 3 species of mosses, 34 species of woody plants, and 95 species of herbaceous plants. At the family level, the most studied plants were members of the Poaceae family, covering 18 species. Regionally, these studies were conducted throughout Korea, but over half of the studies were conducted in Gyeongsangbuk-do, Gangwon-do, and Chungcheongnam-do. Relatively few studies have been conducted in a metropolis such as Seoul. We confirmed 5 phyla, 16 classes, 49 orders, 135 families, 305 genera, and 855 taxa of endophytic fungi, excluding Incertae sedis , whose relationship with others are unknown. Most of the endophytic fungi belonged to Ascomycota (93.2%), and a few belonged to Basidiomycota (3.6%). Since the diversity of endophytic fungi differs depending on the host plant, plant tissue, and distribution region, future studies should be conducted on multiple host plants and in various regions. Future studies on endophytic fungi are expected to broaden, including genomics and taxonomic and ecological studies of secondary metabolites., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the Korean Society of Mycology.)

Background: Along with the rapid transmission of COVID-19, adherence to preventive behaviours plays a crucial role with respect to the control of COVID-19. However, different individuals' psychological characteristics and risk perception result in various forms of response to preventive behaviours. Based on the Health Belief Model, this study identifies the factors associated with preventive behaviours towards COVID-19 in South Korea during the initial stage of the COVID-19 pandemic., Methods: A cross-sectional study was conducted in April 2020 through an anonymous online survey. A total of 1207 people in the age bracket of 20-59 years participated in the survey. Single and multiple linear regression analyses were conducted to identify the determinants of preventive behaviours against COVID-19., Results: The following factors were associated with preventive behaviours towards COVID-19: female gender (β = .124, p < 0.001), has a master's degree or above (β = 0.065, p = 0.010), perceived susceptibility (β = .197, p < 0.001), self-efficacy (β = .404, p < 0.001), trust in radio (β = -.080, p = .006), trust in official government website (β = .057, p = .045), trust in social networks (β = .054, p = .033), and trust in family and friends (β = .068, p = .009), with an explanatory power of 41.5% (R 2  = 0.415)., Conclusions: To flatten the epidemic curve, it is important to understand the public's risk perception and the motivation behind behavioural responses that aim to promote preventive behaviours among the public. Thus, this study calls for the provision of accessible and credible information sources and demonstrates a public health campaign that encourages the public's engagement in preventive behaviours towards COVID-19., (© 2022. The Author(s).)

The efficient strategy for waste conversion and resource recovery is of great interest in the sustainable bioeconomy context. This work reports on the catalytic upcycling of waste corrugated cardboard (WCC) into lactic acid using lanthanide triflates catalysts. WCC, a primary contributor to municipal solid wastes, has been viewed as a feedstock for producing a wide range of renewable products. Hydrothermal conversion of WCC was carried out in the presence of several lanthanide triflates. The reaction with erbium(III) triflate (Er(OTf) 3 ) and ytterbium(III) triflate (Yb(OTf) 3 ) resulted in high lactic acid yields, 65.5 and 64.3 mol%, respectively. In addition, various monomeric phenols were readily obtained as a co-product stream, opening up opportunities in waste management and resource recovery. Finally, technoeconomic analysis was conducted based on the experimental results, which suggests a significant economic benefit of chemocatalytic upcycling of WCC into lactic acid., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Competing Interests: The authors have no potential conflicts of interest to disclose.

Although liquid products derived from the pyrolysis of biomass are promising for the production of petroleum-like hydrocarbon fuels, the catalytic burden of hydrodeoxygenation must be reduced to achieve feasible upgrading processes. Herein, mild hydrotreating of an acid-rich biomass pyrolysis oil (bio-oil) with an unusually high total acid number (588 mg KOH/g bio-oil) was performed to stabilize the low-quality bio-oil. Ru-added TiO 2 -supported transition metal catalysts stabilized the bio-oil by reducing its acidity more compared to what could be achieved by Ru-free catalysts; this process also leads to lower loss of organic compounds compared to when using a Ru/TiO 2 catalyst. Based on the performance of transition metal catalysts, including Ni, Co, and Cu, supported on TiO 2 , tungstate-zirconia, or SiO 2 , supported bimetallic catalysts were prepared by adding Ru to the TiO 2 -supported metal catalysts. The bimetallic catalysts Ru/Ni/TiO 2 and Ru/Co/TiO 2 exhibited good decarboxylation activity for the removal of carboxylic acids and a higher yield of organic compounds compared to that provided by Ru, which can be deemed appropriate for feedstocks when hydrodeoxygenation needs to suppress the loss of organic reactants. Using these catalysts, the carboxylic acid concentration was reduced to 319-323 mg KOH/g bio-oil with organic yields of 62-63 wt% at reaction temperatures 150-170 °C lower than the temperature required for direct conversion of carboxylic acids to alcohols or deoxygenates. The improved catalytic hydrotreating activity of Ru-added transition metals can be attributed to the high acid site densities of these catalysts along with their improved hydrogenation activities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: The relationship between socioeconomic status and the risk of contracting coronavirus disease (COVID-19) remains controversial. We aimed to investigate whether socioeconomic status affected the risk of contracting COVID-19 in the South Korean population., Methods: The NHIS-COVID-19 database cohort was used in this population-based study. We collected the data of COVID-19 patients who were diagnosed between January 1, 2020 and June 4, 2020 and those of the control population. The income levels of all individuals as of February 2020 were extracted, and study participants were classified into four groups based on quartiles: Q1 (the lowest) to Q4 (the highest). Data were statistically analyzed using multivariable logistic regression modeling., Results: In total, 122,040 individuals-7669 and 114,371 individuals in the COVID-19 and control groups, respectively-were included in the final analysis. The multivariable logistic regression model showed that the Q1 group had a 1.19-fold higher risk of contracting COVID-19 than the Q4 group, whereas the Q2 and Q3 groups showed no significant differences. In the 20-39 years age group, compared with the Q4 group, the Q3 and Q2 groups showed 11 and 22% lower risks of contracting COVID-19, respectively. In the ≥60 years age group, compared with the Q4 group, the Q1, Q2, and Q3 groups showed a 1.39-, 1.29-, and 1.14-fold higher risks of COVID-19, respectively., Conclusions: Lower socioeconomic status was associated with a higher risk of contracting COVID-19 in South Korea. This association was more evident in the older population (age ≥ 60 years), whereas both lower and higher socioeconomic statuses were associated with higher risks of contracting COVID-19 in the young adult population (in the 20-39 year age group). Strategies for the prevention of COVID-19 should focus on individuals of lower socioeconomic status and on young adults of higher and lower socioeconomic status.

CARBOHYDRATE-: or sugar-derived compounds were used as environmentally friendly additives for the depolymerization of Kraft lignin waste and organosolv lignin prepared from Miscanthus giganteus. The yields of the aromatic monomers obtained from Kraft lignin increased from 5.1 to 49.2% with the addition of mannitol, while those obtained from organosolv lignin increased from 44.4 to 83.0% with the addition of sucrose. This improved lignin depolymerization was also confirmed by gel permeation chromatography and nuclear magnetic resonance spectroscopy. The above results clearly indicate the beneficial effects of carbohydrate derivatives on the lignin depolymersization process, more specifically, suggesting that the presence of carbohydrates improve the lignin depolymerization of lignocellulose, as observed for the raw lignocellulose feed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objectives: To identify factors associated with the continuum of maternal, newborn and child health care in The Gambia., Design: A secondary statistical analysis using Demographic and Health Survey conducted in 2013., Setting: The Gambia., Participants: 1308 married women (or with a partner) whose most recent children were aged 12-23 months at the time of the survey., Outcome Measures: The main outcome was continuum of care for maternal, newborn and child health. The modified composite coverage index was calculated to express the completion level of continuum of care., Results: The following factors were associated with the continuum of maternal, newborn and child health care: women's autonomy in decision-making of her own healthcare (β=0.063, p=0.015), having higher educated husbands (β=0.138, p<0.001), listening to the radio at least once a week (β=0.078, p=0.006), having a child with birth order less than 5 (β=0.069, p=0.037), initiating the first antenatal care within 16 weeks of pregnancy (β=0.170, p<0.001), having been informed of signs of pregnancy complications (β=0.057, p=0.029), living in rural areas (β=-0.107, p=0.006) and having higher burden due to distance to health facility (β=-0.100, p<0.001), with an explanatory power of 15.5% (R 2 =0.155)., Conclusions: Efforts on future policies and programmes should focus on the concept of continuum of care considering the associated factors. In particular, more attention should be given to providing country-wide family planning and education to women, men and community members in The Gambia., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: As of April 30, 2020, a total of 2,039 cases of the novel coronavirus disease 2019 (COVID-19) were confirmed in the Republic of Uzbekistan after the first detection on March 15. Reports on symptoms of COVID-19 are non-specific and known to vary from asymptomatic, mild to severe, or fatal. This study aimed to analyze the symptomatic and clinical characteristics of study participants based on the medical records of participants hospitalized with COVID-19 in Uzbekistan., Methods: We collected all data from medical records of COVID-19 confirmed patients in 19 hospitals from 13 regions of Uzbekistan between March 15 and April 30. We selected 1,030 patients discharged from the hospitals after COVID-19 treatment as study participants, excluding those with missing data. Further, we collected demographics, symptoms, clinical outcomes, and treatment data through medical records., Results: More than half (57.6%) of confirmed cases of COVID-19 were males, and the median age was 36.0 years. The most frequent symptoms at the first inspection on hospital admission of all patients were fatigue (59.7%), dry cough (54.1%), pharyngalgia (31.6%), headache (20.6%), and anorexia (12.5%). Compared to the oldest group, the youngest group showed a lower frequency of symptoms. About half of the group aged 18-49 years reported that they came from abroad. One-fifth of patients in group 50-84 received oxygen support, while no patients in group aged 0-17 years received oxygen support. About two-thirds of the participants from intensive care unit (ICU) came from abroad, whereas 42.1% of the non-ICU group returned from other countries. Regarding symptoms, 16.9% of the patients in the ICU group were asymptomatic, while 5.8% in the non-ICU group were asymptomatic., Conclusion: This study suggests that the medical delivery system and resource distribution need to be implemented based on clinical characteristics by age and severity to delay and effectively respond to the spread of infections in the future. This study analyzed symptoms of COVID-19 patients across Uzbekistan, which is useful as primary data for policies on COVID-19 in Uzbekistan., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2020 The Korean Academy of Medical Sciences.)

SiO 2 @MnO x @Na 2 WO 4 @SiO 2 core-shell catalysts were prepared and their fabrication was confirmed using transmission electron microscopy. The formation of Mn-based nanosheets on the silica spheres is important for the deposition of nanoscopic Na 2 WO 4 . The SiO 2 @MnO x @Na 2 WO 4 @SiO 2 core-shell catalysts were used for the oxidative coupling of methane at a temperature of 700-800 °C at which the nanostructures were completely destroyed. Although the core-shell structures did not survive the high-temperature oxidative coupling of methane, the selective production of olefins and paraffins can be attributed to highly dispersed Na 2 WO 4 derived from confined core-shell structures., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The coverage of the fifth-generation network has increased steadily since the network was introduced in 2019. However, public protests around the globe against the construction of 5G network base stations have continued to occur for fear that electromagnetic (EM) waves emitted from the stations would cause adverse health effects. To identify factors that have contributed to such increased risk perception, we conducted a cross-sectional study using data obtained from a survey that assessed Korean adults' risk perception of EM wave-related objects. We found that female gender, high level of perceived exposure to EM waves, evaluation of public policies as ineffective, and high level of objective knowledge on EM waves were associated with increased risk perception. Furthermore, we found that higher ratings on a few risk characteristics such as "personal knowledge," "seriousness of the risk to future generations," "dreadfulness," and "severity of consequences" were also associated with increased risk perception as well. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society., (© 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.)

This study examines differences between the level of objective knowledge regarding radio-frequency electromagnetic fields (RF-EMF) and risk perception of cell phones in Korea. We also investigate the extent to which socio-demographic factors, perceived EMF exposure, objective knowledge regarding EMF, and psychological factors influence the risk perception of cell phones using hierarchical multiple regression. All 3393 study subjects completed a survey measuring the degree of risk perception of EMF. They were sampled in accordance with representative proportions of sex, age group, and region of residence as shown in the 2019 Resident Registration Population Statistics reported by Korea. The variables that have the most influence on risk perception of cell phones can be induced from the beta values for each variable: The subjective factor, perceived level of exposure to EMF (β = 0.253), was more strongly related to risk perception of cell phones than level of knowledge regarding EMF, an objective factor in this study. Of the psychological factors, Dreadfulness (β = 0.331), Personal knowledge (β = -174), and Familiarity (β = -089) influenced risk perceptions of cell phones; Controllability did not. On the risk cognition map, people though that it was easy to control risk related to Cell phone use in daily life, while risk related to High technology was uncontrollable.

This study examined the effects of oxygen species on the unsteady-state oxidative coupling of methane (OCM) using a lengthy catalyst bed of Na 2 WO 4 /Mn/SiO 2 . The reaction conditions, including the methane-to-oxygen ratio, ratio of feed gas dilution by N 2 , quantity of catalyst, and feed flow rate were adjusted for the continuous flow fixed bed reaction system. While the O 2 gas initiated methyl radical formation from methane, the surface lattice oxygen atoms improved the dehydrogenation of paraffins to olefins without significant activation of methane. The addition of CO 2 as a mild oxidizing agent was also tested and slightly improved OCM selectivity with slightly lower methane conversion were observed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: The Korean National Health Insurance Service (NHIS) was developed to provide population data for medical research. The aim of this study was to estimate trends in prescription opioid use in South Korea, and to determine the association between chronic opioid use and 5-yr mortality in cancer and non-cancer patients., Methods: A population-based cohort study was conducted amongst the South Korean adult population using data from the NHIS. Those prescribed a continuous supply of opioids for ≥90 days were defined as chronic opioid users. Multivariable Cox regression analysis was used to assess the association between chronic opioid use and 5-yr mortality., Results: The proportion of chronic weak opioid users increased from 1.03% in 2002 to 9.62% in 2015. The proportion of chronic strong opioid users increased from 0.04% in 2002 to 0.24% in 2015. In the 2010 cohort (n=822 214), compared with non-users, chronic weak opioid users had a significantly lower 5-yr mortality (hazard ratio [HR]: 0.93; 95% confidence interval [CI]: 0.89-0.96; P<0.001), and chronic strong opioid users had a significantly higher 5-yr mortality (HR: 1.45; 95% CI: 1.28-1.63; P<0.001). Similar results were observed in non-cancer patients, but chronic weak opioid users were not significantly associated with 5-yr mortality in cancer patients (P=0.063)., Conclusions: In South Korea, chronic opioid use has increased since 2002. Chronic strong opioid use was associated with a higher 5-yr mortality, and chronic weak opioid use was associated with a slightly lower 5-yr mortality. However, the findings regarding chronic weak opioid users should be interpreted carefully because there might be residual confounders in this study. Further study is needed to confirm these retrospective findings., (Copyright © 2019. Published by Elsevier Ltd.)

Background: This study aimed to analyze the barriers affecting the utilization of antenatal care (ANC) among Senegalese mothers., Methods: Health facility staffs were surveyed to examine the availability coverage of ANC (infrastructural capacity of health posts to handle maternal and newborn healthcare). A total of 113 women of childbearing age were surveyed to identify factors associated with the accessibility coverage (physical, economic, and information accessibility factors), acceptability coverage (socio-cultural features, social acceptance, and language), and effectiveness coverage (ratio of mothers having completed 4 visits) of ANC. Further, to identify the socio-cultural factors and the specific characteristics of the barriers, 5 focus group discussions were conducted with women of childbearing age, their husbands and mothers-in-law, community health workers, and health facility staff. The effectiveness coverage of ANC was analyzed by reviewing materials from the District Health Information System 2 of Senegal., Results: Key barriers of ANC utilization were associated with acceptability coverage. ANC during early pregnancy was avoided owing to the negative social stigma surrounding miscarriage. The survey results indicated an extremely high miscarriage rate of 30.9% among the participants. The social stigma towards unmarried mothers caused them to hide their pregnancy, which deterred ANC utilization. The husband was the final decision maker and social supporter on ANC utilization., Conclusion: To promote the utilization of ANC services among pregnant women in Senegal, it is important to alleviate the social stigma towards miscarriages and unmarried mothers, and to provide greater social support for pregnancies and newborn deliveries within family., Competing Interests: Disclosure: The authors have no potential conflicts of interest to disclose.

Purpose: Patients receiving palliative care make avoidable emergency department visits (AvED), which may increase economic and social costs. However, the proportion of AvED among all patients, including cancer patients after curation, and the resulting costs are unknown in Asia. This study aimed to investigate the proportion, characteristics, and costs regarding factors associated with AvED among cancer patients., Methods: This retrospective cohort study analyzed the medical records of patients who visited the emergency department (ED) at a tertiary care hospital in Korea in 2016. Data regarding patients' demographic, cancer-related, and clinical characteristics were collected., Results: ED visits by a total of 4346 patients were included in the analysis, of which 2420 visits (55.7%) were avoidable. In the multivariate logistic model, the following main factors were associated with AvED: stay in ED (odds ratio [OR] 0.998, 95% confidence interval [CI] 0.997-0.999, P < 0.001), distance to the home from the ED (OR 0.998, 95% CI 0.997-0.999, P < 0.001), multiple ED visits in 1 year (OR 1.204, 95% CI 1.156-1.255, P < 0.001), primary progression (vs. after curation) (OR 0.748, 95% CI 0.627-0.892, P = 0.001), and chief complaint being a gastrointestinal symptom (vs. pain) (OR 1.871, 95% CI 1.188-2.946, P = 0.007). The average cost per visit in the AvED group was $369.80, and the annual total cost for all AvEDs was $894,877., Conclusions: Our study showed that 55.7% of all ED visits by cancer patients visiting the ED of a tertiary care hospital were avoidable, and several factors were associated with AvED.

The duration and frequency of mobile phone calls, and their relationship with various health effects, have been investigated in our previous cross-sectional study. This 2-year period follow-up study aimed to assess the changes in these variables of same subjects. The study population comprised 532 non-patient adult subjects sampled from the Korean Genome Epidemiology Study. The subjects underwent a medical examination at a hospital in 2012/2013 and revisited the same hospital in 2014/2015 to have the same examination for the characteristics of mobile phone use performed. In addition, to evaluate the effects on health, the Headache Impact Test-6 (HIT-6), Psychosocial Well-being Index-Short Form, Beck Depression Inventory, Korean-Instrumental Activities of Daily Living, Perceived Stress Scale, Pittsburgh Sleep Quality Index, and 12-item Short Form Health Survey were analyzed. For all these tests, the higher the score, the greater the effect on health. Variances between scores in all the indices in the baseline and follow-up surveys were calculated, and correlations of each index were analyzed. The average duration per call and HIT-6 score of the subjects decreased significantly compared with those recorded two years ago. The results showed a slight but significant correlation between call duration changes and HIT-6 score changes for female subjects, but not for males. HIT-6 scores in the follow-up survey significantly decreased compared to those in the baseline survey, but long-time call users (subjects whose call duration was ≥5 minutes in both the baseline and follow-up surveys) had no statistically significant reduction in HIT-6 scores. This study suggests that increased call duration is a greater risk factor for increases in headache than any other type of adverse health effect, and that this effect can be chronic.

Objectives: This study analyzed the associations between mobile phone call frequency and duration with non-specific symptoms., Methods: This study was conducted with a population group including 532 non-patient adults established by the Korean Genome and Epidemiology Study. The pattern of phone call using a mobile phone was investigated through face-to-face interview. Structured methods applied to quantitatively assess health effects are Headache Impact Test-6 (HIT-6), Psychosocial Well-being Index-Short Form, Beck Depression Inventory, Korean-Instrumental Activities of Daily Living, Perceived Stress Scale (PSS), Pittsburgh Sleep Quality Index, and 12-item Short Form Health Survey where a higher score represents a higher greater health effect., Results: The average daily phone call frequency showed a significant correlation with the PSS score in female subjects. Increases in the average duration of one phone call were significantly correlated with increases in the severity of headaches in both sexes. The mean (standard deviation) HIT-6 score in the subgroup of subjects whose average duration of one phone call was five minutes or longer was 45.98 (8.15), as compared with 42.48 (7.20) in those whose average duration of one phone call was <5 minutes. The severity of headaches was divided into three levels according to the HIT-6 score (little or no impact/moderate impact/substantial or severe impact), and a logistic regression analysis was performed to investigate the association between an increased phone call duration and the headache severity. When the average duration of one phone call was five minutes or longer, the odds ratio (ORs) and the 95% confidence intervals (CIs) for the moderate impact group were 2.22 and 1.18 to 4.19, respectively. The OR and 95% CI for the substantial or severe impact group were 4.44 and 2.11 to 8.90, respectively., Conclusions: Mobile phone call duration was not significantly associated with stress, sleep, cognitive function, or depression, but was associated with the severity of headaches., Competing Interests: The authors have no conflicts of interest associated with the material presented in this paper.

This experimental study examined differences in doctor-patient relationships according to the health communication strategies during cases of medical malpractices occurred at primary medical institution. A total of 116 subjects aged in their 20s-50s was sampled. The first medical malpractice scenario chosen was the medical malpractice case most frequently registered at the Korean Medical Association Mutual Aid and the second scenario was associated with materials and devices as the cause of malpractice. Four types of crisis communication strategy messages were utilized, consisting of denial, denial + ingratiation, apology, and apology + ingratiation. Subjects were classified into four research groups by crisis communication strategy to measure levels of trust, control mutuality, commitment, and satisfaction, before and after the occurrence of medical malpractice and application of communication strategies. The findings of this study revealed that the apology strategy, compared with the denial strategy, showed a smaller difference before and after the application of communication strategies in all variables of trust (F = 8.080, F = 5.768), control mutuality (F = 8.824, F = 9.081), commitment (F = 9.815, F = 8.301), and satisfaction (F = 8.723, F = 5.638). Further, a significant interaction effect was shown between variables. The apology strategy, compared with the denial strategy, was effective in the improvement of doctor-patient relationships in both Scenarios I and II. For Scenario I, the apology strategy without ingratiation boosted commitment and satisfaction, but for Scenario II, utilizing the apology strategy with ingratiation boosted the effectiveness of trust and commitment.

Aromatic hydrocarbons were produced from lignin, a complex natural amorphous polymer commonly regarded as by-product of the pulping process and from biofuel production. The catalytic decomposition of lignin using supported Pt catalysts was performed to produce small molecule hydrocarbons. Aromatic small-molecule hydrocarbon products were identified and quantified using GC/MS and GC-FID, which demonstrated that 27.6% of aromatic hydrocarbons were obtained from the activated carbon-supported Pt (Pt/AC) catalyst which had the highest Pt surface area.

Alkali lignin, a byproduct of the pulping process, was depolymerized using Pt nanoparticle catalysts. A depolymerized lignin with a lower molecular weight was obtained and characterized with GPC and NMR. 31P-NMR using OH-sensitive probing molecules showed the formation of guaiacyl OHs during the reaction, indicating the cleavage of guaiacyl ether bonds.

A high contact resistance for screen-printed contacts was observed when a conventional Ag paste was used on a boron emitter. The results of this study suggest that electron injection during firing is one of the processes that contribute to a lower contact resistance. Larger quantities of Ag precipitates formed upon electron injection into the boron emitter, which was confirmed by observing Ag crystallite or dendrite structures on the boron and by measuring the contact resistance between the boron emitter and the Ag bulk. The electron-injected sample had approximately 10000 times lower contact resistance than an untreated sample. The contact resistance of the electron-injected sample was 0.021 mΩ ∙ cm(2) under optimal conditions, which is lower than that of conventional p-type silicon solar cells. Thus, electron injection can effectively lower contact resistance when using Ag paste in n-type silicon solar cells. During the cooling in the firing process, dissolved Ag ions in the glass layer are formed as dendrites or crystallites/particles. The dendrites are formed earlier than others via electrochemical migration under electron injection conditions. Then, crystallites and particles are formed via a silicon etching reaction. Thus, Ag ions that are not formed as dendrites will form as crystallites or particles.

We have reported a high prevalence of breast cancer in light-polluted areas in Korea. However, it is necessary to analyze the spatial effects of light polluted areas on breast cancer because light pollution levels are correlated with region proximity to central urbanized areas in studied cities. In this study, we applied a spatial regression method (an intrinsic conditional autoregressive [iCAR] model) to analyze the relationship between the incidence of breast cancer and artificial light at night (ALAN) levels in 25 regions including central city, urbanized, and rural areas. By Poisson regression analysis, there was a significant correlation between ALAN, alcohol consumption rates, and the incidence of breast cancer. We also found significant spatial effects between ALAN and the incidence of breast cancer, with an increase in the deviance information criterion (DIC) from 374.3 to 348.6 and an increase in R2 from 0.574 to 0.667. Therefore, spatial analysis (an iCAR model) is more appropriate for assessing ALAN effects on breast cancer. To our knowledge, this study is the first to show spatial effects of light pollution on breast cancer, despite the limitations of an ecological study. We suggest that a decrease in ALAN could reduce breast cancer more than expected because of spatial effects.

Objectives: There has been a growing concern about the possible carcinogenic effects of the electromagnetic radiofrequency fields emitted from mobile phones. The purpose of this study was to investigate the association between mobile phone use and the development of gliomas in Korea., Methods: Our study methods were based on the International Interphone study that aimed to evaluate possible adverse effects of mobile phone use. This study included 285 histologically-confirmed Korean patients 15 to 69 years of age, with gliomas diagnosed between 2002 and 2007 in 9 hospitals. The 285 individually matched controls were healthy individuals that had their medical check-up in the same hospitals. Unconditional logistic regression was used to calculate the adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for use of mobile phones., Results: For the entire group, no significant relationship was investigated between gliomas and regular use of mobile phones, types of mobile phones, lifetime years of use, monthly service fee, and the other exposure indices. Analyses restricted to self-respondents showed similar results. For ipsilateral users, whose the body side for usual mobile phone use match the location of glioma, the aORs (95% CIs) for lifetime years of use and cumulative hours of use were 1.25 (0.55 to 2.88) and 1.77 (0.32 to 1.84), respectively. However, the contralateral users showed slightly lower risk than ipsilateral users., Conclusions: Our results do not support the hypothesis that the use of mobile phones increases the risk of glioma; however, we found a non-significant increase in risk among ipsilateral users. These findings suggest further evaluation for glioma risk among long-term mobile phone users.

Objectives: In light of the need to develop an integrated database on poisoning incidents in Korea, this study seeks to determine the characteristics of poisoning incidents in Korea by age, gender, location of incident, causative substance and patient prognosis., Data Sources: The Korea National Hospital Discharge In-Depth Injury Survey results (2005-2009) from the Korea Centers for Disease Control and Prevention were used., Participants: 3826 participants in the survey who had been hospitalised for poisoning incidents., Results: The poisoning hospitalisation rate per 100,000 population was higher in women (1.735) than in men (1.372) and increased with age: the rate was 0.458 among individuals aged ≤9 years, 0.481 among those aged 10-19 years, 1.584 among those aged 20-64 years and 4.053 among those aged ≥65 years. The intentional poisoning hospitalisation rate differed by gender and age group. Women aged ≤19 years and 20-64 years showed a higher hospitalisation rate than men, while men aged ≥65 years showed a higher hospitalisation rate than women in the same age group. The most common poisoning substance was pesticides (33.6%), while antiepileptic, sedative-hypnotic and antiparkinsonism drugs and psychotropic drugs, not elsewhere classified were also very common. Poisoning in those aged ≤9 years usually involved other drugs, while pesticides were the most common substances in those aged 20-64 years and ≥65 years., Conclusions: This study analysed poisoning incidents in Korea from 2005 to 2009, by age and gender, causative substance, and characteristics. The results of this study may serve as evidence for new strategies in Korea to prevent poisoning., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

We report that vanadium dioxide films patterned with λ/100000 nanogaps exhibit an anomalous transition behavior at millimeter wavelengths. Most of the hybrid structure's switching actions occur well below the insulator to metal transition temperature, starting from 25 °C, so that the hysteresis curves completely separate themselves from their bare film counterparts. It is found that thermally excited intrinsic carriers are responsible for this behavior by introducing enough loss in the context of the radically modified electromagnetic environment in the vicinity of the nanogaps. This phenomenon newly extends the versatility of insulator to metal transition devices to encompass their semiconductor properties.

Introduction: Cameroon is classified by the World Health Organization (WHO) as having a critical shortage of health personnel. This is further complicated by the geographic distributional inequalities of the national health workforce. This shortfall impedes Cameroons' progress of improving the human resources for health (HRH) to meet up with the Millennium Development Goals (MDGs) by 2015. However, it is unknown whether the health workforce of Cameroon is distributed equally across geographic regions. Additionally, indicators other than population levels have not been used to measure health care needs. This study aimed to assess the adequacy, evenness of distribution and challenges faced by the health workforce across the different regions of Cameroon., Methods: National health personnel availability and distribution were assessed by use of end-of-year census data for 2011 obtained from the MoPH data base. The inequalities and distribution of the workforce were estimated using Gini coefficient and Lorenz curve and linear regression was used to determine the relation between health personnel density and selected health outcomes. Alternative indicators to determine health care needs were illustrated using concentration curves., Results: Significant geographic inequalities in the availability of health workforce exist in Cameroon. Some regions have a higher number of physicians (per person) than others leading to poor health outcomes across the regions. 70 % of regions have a density of health personnel-to-population per 1,000 that is less than 1.5, implying acute shortage of health personnel. Poor working and living conditions, coupled with limited opportunities for career progress accounted for some documented 232 physicians and 205 nurses that migrated from the public sector. Significant distributional inequality was noticed when under-five infant mortality and malaria prevalence rate were used as indicators to measure health care needs., Conclusion: Our results show an absolute shortage of public health personnel in Cameroon that is further complicated by the geographic distributional inequalities across the regions of the nation. Cameroon aims to achieve universal health coverage by 2035; to realize this objective, policies targeting training, recruitment, retention and effective deployment of motivated and supported health workforce as well as the development and improvement of health infrastructures remain the major challenge.

In this study, the risk perception level of each light pollution type was analyzed, and the effects of the variables (e.g., psychometric paradigm factor, trust in the government, etc.) on the process of the increase in the risk perception were analyzed. For the sample population (1096 persons) in Korea, the risk perception levels of each light pollution type and other environmental and health risk factors were compared, and the relative magnitude was examined. In addition, to test which variables affect the group with high-risk perception of each light pollution type, a logistic regression analysis was performed. For the group with highest risk perception of light pollution, the odds ratios (OR) of all psychometric paradigms (excluding controllability) increased compared to those of the group with low-risk perception. Additionally, the level showing the acquisition of information from the media and the recollection level of media criticism on each light pollution type showed a statistically significant increase. Especially, the risk perception of light trespass increased as trust in the government decreased. The significance of this study includes the finding that the public's risk perception of light pollution was significantly affected by the psychometric paradigm factors. Moreover, this study analyzed the differences of the variables that affect the increase in the risk perception of each light pollution type and provided a theoretical framework that can practically reflect the strategy for the risk communication of light pollution.

Purpose: This study was performed to investigate polycyclic aromatic hydrocarbons (PAHs) exposure in the area around a cement factory with kilns using waste, including refuse plastic fuel., Methods: Atmospheric total suspended particulates (TSPs) for each of an exposed area and a non-exposed area were collected. Similarly, urine samples were collected from 330 subjects in the exposed area and 126 subjects in the non-exposed area. Gas chromatography with mass spectrometry was used to analyze PAHs in the collected TSP samples and the PAH metabolites, urinary 2-naphthol (2-NAP) and 1-hydroxypyrene (1-OHP), of the residents. The concentrations of urinary 2-NAP and 1-OHP were adjusted by creatinine concentrations., Results: The atmospheric concentrations of PAHs, including naphthalene and pyrene, were higher in the exposed area than those in the non-exposed area. The geometric means (GMs) of the urinary 2-NAP concentrations in the exposed and non-exposed groups without work experience were 4.06 and 1.55 μg/g creatinine, respectively. The GMs of the urinary 1-OHP concentrations were 0.26 and 0.14 μg/g creatinine, respectively. The results showed that the concentrations of PAH metabolites were significantly higher in the exposed group than those in the non-exposed group (p < 0.001). Multiple linear regression analysis with the log-transformed urinary 2-NAP and 1-OHP concentrations and other variables indicated a strong correlation of residence in the exposed area and smoking with an increase in the urinary 2-NAP and 1-OHP concentrations., Conclusions: In addition to the known risk factors, this study indicated that living near a cement factory with kilns is also a risk factor for PAH exposure.

In this study, the difference between the risk perception of electromagnetic waves from cellular phones and the risk perception of other factors such as environment and food was analyzed. The cause of the difference in the psychological and social factors that affect the group with high risk perception of electromagnetic waves was also analyzed. A questionnaire survey on the risk perception of electromagnetic waves from cellular phones was carried out on 1001 subjects (men and women) over the age of 20. In the group with high risk perception of electromagnetic waves from cellular phones, women had higher risk perception than men. Logistic regression analysis, where the group with high risk perception of electromagnetic waves and the group with low risk perception were used as dependent variables, indicated that the risk perception of electromagnetic waves in women was 1.815 times statistically significantly higher than the risk perception of men (95% CI: 1.340-2.457). Also, high risk perception of electromagnetic waves from cellular phones was observed when the subjects considered that they had more personal knowledge (OR: 1.416, 95% CI: 1.216-1.648), that the seriousness of the risk to future generations was high (OR: 1.410, 95% CI: 1.234-1.611), and their outrage for the occurrence of accidents related to electromagnetic waves was high (OR: 1.460, 95% CI: 1.264-1.686). The results of this study need to be sufficiently considered and reflected in designing the risk communication strategies and communication methods for the preventive measures and advice on electromagnetic waves from cellular phones., (© 2014 Wiley Periodicals, Inc.)

Objective: This article was intended to introduce the Korean Surveillance System for Childhood Asthma (KSSCA) and also to determine the factors that increase the risk for the development of asthma and allergic diseases in preschool children in Korea based on the study results., Methods: The KSSCA pilot study was a web-based, cross-sectional survey that sampled 1002 parents with a biological child aged 2-6 years that visited the website and participated in the survey. This website consisted of a questionnaire designed to measure the history and prevalence of asthma and allergic diseases, the characteristics of dwelling, lifestyle, and the socioeconomic status of the subjects. Using logistic regression analysis, odds ratios (ORs) and 95% confidence intervals (CIs) between each risk factor and disease development were calculated., Results: The rate of a family where a child had asthma was 7.4%, while 34.7% and 35.9% for allergic rhinitis and atopic dermatitis, respectively. The OR (95% CI) that a child whose parents had an allergic disease and was also diagnosed with an allergic disease was 2.86 (2.20-3.72). Children who lived in the first floor or basement of apartments had a higher risk of atopic dermatitis, as well as children from socioeconomically vulnerable families. Upon analysis of allergic reaction tests and disease development, it was found that asthma was associated with the positive reaction of cockroaches and food, allergic rhinitis with mites, and atopic dermatitis with mold and food., Conclusion: The study indicated that genetic and some environmental or socioeconomic factors might be important in the development of asthma and allergic diseases among preschool children in Korea through the web-survey.

The purpose of this study was to investigate demographic and lifestyle variables and blood cadmium concentrations in residents living near abandoned metal mines in Korea. Blood cadmium concentrations were measured in 15,161 subjects living around abandoned metal mines (exposed group, n = 14,464) and compared with those living in designated control areas (control group, n = 697). A questionnaire was provided to all subjects to determine age, gender, mine working history, times of residence, smoking habits and dietary water type. The geometric mean (95% confidence intervals) of blood cadmium concentration (1.25 [1.24-1.27] µg/L) in the exposed group was significantly higher than in the control group (1.17 [1.13-1.22] µg/L). Mean residence time and mine working history in the exposed group were significantly higher than in the control group. Blood cadmium concentrations increased with increasing age, and residence time in both groups, and blood cadmium concentrations were higher in current-smokers than in non-smokers in both groups. This study shows the geometric mean of blood cadmium concentration in abandoned mining areas are higher than in non-mining areas in the general adult Korean population.

In this study, we measured the morphometric and histological changes in the cyprinid loach, Misgurnus anguillicaudatus, during the early period of growth. Eyes, yolk length, yolk height, and yolk volume of the larva decreased for 16 days post hatching (DPH) (P<0.05). During 60 DPH (P>0.05), the most anterior extension of the head × the posterior end of the supraoccipital, the most anterior extension of the head × the origin of the dorsal fin, the most anterior extension of the head × the origin of the pectoral fin, the posterior end of the supraoccipital × the origin of the pelvic fin, and the origin of the dorsal fin × the ventral origin of the caudal fin gradually decreased, whereas the most anterior extension of the head × the dorsal origin of the caudal fin, the origin of the dorsal fin × the origin of the anal fin, the origin of the dorsal fin × the origin of the pectoral fin, and the insertion of the dorsal fin × the origin of the pelvic fin gradually increased (P<0.05). In the cyprinid loach, the retina is composed of six layers: the epithelial layer, ganglion cell layer, inner nuclear layer, inner plexiform layer, outer limiting membrane, and rod and cone layer (RCL). After hatching, part of the RCL gradually increased in density. The kidney and midgut epithelium were already formed in the cyprinid loach just after hatching and grew gradually in subsequent days.

Objectives: This study was conducted to review the validity of the need for the application of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) to household chemical products in Korea. The study also aimed to assess the severity of health and environmental hazards of household chemical products using the GHS., Methods: 135 products were classified as 'cleaning agents and polishing agents' and 98 products were classified as 'bleaches, disinfectants, and germicides.' The current status of carcinogenic classification of GHS and carcinogenicity was examined for 272 chemical substances contained in household chemical products by selecting the top 11 products for each of the product categories. In addition, the degree of toxicity was assessed through analysis of whether the standard of the Republic of Korea's regulations on household chemical products had been exceeded or not., Results: According to GHS health and environmental hazards, "acute toxicity (oral)" was found to be the highest for two product groups, 'cleaning agents and polishing agents', and 'bleaches, disinfectants, and germicides' (result of classification of 233 household chemical products) at 37.8% and 52.0% respectively. In an analysis of carcinogenicity assuming a threshold of IARC 2B for the substances in household chemical products, we found 'cleaning agents and polishing agents' to contain 12 chemical substances and 'bleaches, disinfectants, and germicides' 11 chemical substances., Conclusion: Some of the household chemical products were found to have a high hazard level including acute toxicity and germ cell mutagenicity, carcinogenicity, and reproductive toxicity. Establishing a hazard information delivery system including the application of GHS to household chemical products in Korea is urgent as well.

Arsenic (As) pollution in the surroundings of metal mines has been observed, and may induce serious health problems, in particular cancer. Health hazard attributed to As in contaminated soil and water in the vicinity of closed or abandoned metal mines may be high. Little is known about how environmental exposure to As has affected the health of resident near closed metal mines. The objectives of this study were to compare the urinary level of As for those living near closed metal mines (the exposed group) with that of non-exposed group; and to investigate the correlation between As levels in soil (SoilAs) and water (WaterAs) and the urinary levels (UrineAs) of residents in the exposed group. Data for SoilAs and WaterAs were obtained from the national environmental survey performed between 2003 and 2005 by the Ministry of Environment in Korea. To measure UrineAs, 2674 and 237 subjects were selected from 67 closed metal mines (exposed areas) and two rural areas (non-exposed areas), respectively. Five milliliters of urine samples were taken, and graphite furnace atomic absorption spectrometry was used to analyze UrineAs. Of all the exposed areas, high SoilAs and WaterAs areas that exceed the Korean standards of As in soil (6 mg/kg-soil) and stream or groundwater (0.05 mg/l-water) were classified to evaluate the health risks in high polluted areas. Also, high UrineAs group was defined as 20 μg/g creatinine or more. Student's t-test was performed to compare the UrineAs level between the exposed and non-exposed groups. The odds ratio (OR) was calculated by a logistic analysis to evaluate the risk for high UrineAs level from high SoilAs and WaterAs areas. The mean of urinary As were 8.90 ± 8.34 μg/g-creatinine for the exposed group and 7.68 ± 4.98 μg/g creatinine for the non-exposed group, respectively; and the significant difference of urinary As level was observed between both groups (p<0.05). Moreover, the means for urinary As of people in areas with high As level in soil and water were significantly higher than that for the control areas (p<0.001), and these differences were more pronounced for the As level in water. The odds of subjects with high UrineAs were positively and significantly associated with living in the areas with high As level in soil (OR=1.62; 95% C.I.=1.13-2.31). These associations were much stronger for the areas with high WaterAs (OR=3.79; 95% C.I.=2.32-6.19). These results indicate that the high level of As in environment may increase the risk of having high urinary As level of people in the exposed areas., (Copyright © 2012 Elsevier GmbH. All rights reserved.)

The coagulation cascade and inflammatory process are known to be associated with the pathophysiology of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). We retrospectively investigated laboratory values indicating coagulopathy obtained within 24 hr from diagnosis of ALI/ARDS in 79 children who received mechanical ventilation between 2008 and 2009 and their final outcomes. Prothrombin time (PT) (P = 0.001) and activated partial thromboplastin time PTT (APTT) (P = 0.001) were more prolonged in non-survivors than survivors (mean; 1.57 vs 1.33; 63 vs 57). In multivariate analysis with stratification by oxygenation-index (< 14.5, ≥ 14.5), prolonged PT (≥ 1.46 international normalized ratio, [INR]) (hazard ratio; 2.043, 1.027-4.064) was associated with lower non-pulmonary-organ-failure-free survival rate (FFS), and prolonged APTT (≥ 50 seconds) (2.062, 1.031-4.121; 2.422, 1.227-4.781) was associated with lower overall survival rate (OS) and lower FFS. In stratification by ventilation-index (< 40, ≥ 40), prolonged PT (2.232, 1.095-4.540; 2.177, 1.092-4.342) and prolonged APTT (2.574, 1.230-5.386; 3.089, 1.500-6.360) were associated with lower OS and lower FFS. Prolonged PT and APTT are associated with mortality in mechanically ventilated children with ALI/ARDS. We suggest PT and APTT as prognostic factors of ALI/ARDS in children.

We studied the electromagnetic interaction between two asymmetric terahertz nano resonators, rectangular holes which have a few hundred micron lengths but nanoscale widths. We report that the dominant resonant transmission of the structures can be modulated by the horizontal distance between two rectangles due to the different oscillation strength of the asymmetric coupling at two different resonance frequencies. Our results are significant for an optimum design of rectangular holes in terahertz frequency regime for applications such as sensitive nanoparticle detection and terahertz filters.

In 2007, as part of the control and prevention of environmental contamination threatening public health, the Korean Ministry of Environment planned to implement a national biomonitoring survey of three metals: lead, cadmium, and mercury in the blood of residents living near 350 abandoned metal mines known to be contaminated and as possible threats to the health of inhabitants. Thus, we investigated demographic and lifestyle variables and blood lead levels in residents living around the mines and compared them against those of control subjects. We measured the blood lead concentrations in 14,849 subjects (14,132 from nearby the 350 abandoned metal mines and 717 subjects from eight control areas). A questionnaire was provided to all subjects to determine gender, age, mining experience, period of time living in the vicinity of mines, smoking status, and personal perception of abandoned mines as a health risk. The geometric means (95% confidence intervals) of the blood lead levels of residents living around the abandoned metal mines and control areas were 3.017 (2.996-3.037 μg/dL) [female, 2.797 μg/dL (2.771-2.822 μg/dL); male, 3.330 μg/dL (3.298-3.363 μg/dL)] and 2.757 (2.677-2.837 μg/dL) [female, 2.604 μg/dL (2.506-2.700 μg/dL); male, 2.993 μg/dL (2.859-3.126 μg/dL)], respectively. Among residents of the mining areas, nonsmokers and residents who had no mining experience showed significantly lower mean blood lead levels than did smokers, past smokers, and those with mining experience. The mean blood lead concentrations of residents who expressed some concern about the abandoned mines were significantly higher than those of residents without concerns. The mean blood lead concentration of residents living around the abandoned mines was significantly higher than that of residents living in control areas as well as that of the general adult Korean population. We also confirmed that smoking is an important variable to consider, as it increases blood lead concentration.

We report a case of a 3-year-old boy with hemophagocytic lymphohistiocytosis (HLH), with enlarged cervical lymph nodes causing internal jugular vein compression, who initially presented a condition similar to the superior vena cava syndrome. Laboratory data along with neck node and bone marrow biopsies confirmed the HLH. Genetic analysis revealed the patient to be compound heterozygous for 2 variations of the perforin gene, c.1620 A>G and c.562C>G. This case featuring a rare initial manifestation of HLH that has not been previously reported, points to the necessity of considering this disease when symptoms similar to superior vena cava syndrome are encountered.

To identify the association between residential environmental risk factors and the prevalence of childhood asthma, the authors surveyed the prevalence of asthma, the residential environmental risk factors of 1819 elementary school students, and air pollution in metropolitan (Seongbuk), and semirural (Andong) areas. Although there was no significant difference in the prevalence of self-reported asthma (SA) between the 2 geographic areas (12.8% vs 13.6%), the prevalence of physician-diagnosed asthma (PDA) in Andong (15.0%) was significantly higher than that in Seongbuk (6.8%). After adjusting for confounding factors, logistic regression suggested that there were significant differences in size of the house (adjusted odds ratio [aOR] = 1.82), medical insurance (aOR = 2.59), and number of residents in the household (aOR = 1.54) between the SA and non-SA groups. There was a significant difference in the area of residence (aOR = 2.12) between the PDA and non-PDA groups. In conclusion, residential environmental risk factors and the area of residence affect the prevalence of childhood asthma.

A tailored health promotion program was developed and applied to reduce cardiovascular disease risk factors among middle-aged and advanced-age bus drivers. The participants were 248 bus drivers from 2 transportation companies, in whom the authors surveyed health behaviors (physical activity, diet, smoking habit, and alcohol consumption), health status (body mass index, systolic blood pressure, triglycerides, total cholesterol, high-density lipoprotein, and low-density lipoprotein), and job stress. The tailored health promotion program consisted of exercise, diet, temperance, and smoking cessation education; the program was developed to reduce cardiovascular disease risk factors and was administered for 6 months. After the program, health behaviors, such as physical activity, dietary habits, smoking habits, and alcohol consumption, and health status indicators, such as blood pressure, had significantly improved (P < .05). The authors did not find an association between job stress and health behavior and status. This suggests that a tailored health promotion program for middle-aged and advanced-age bus drivers was effective.

The authors developed a stepwise exercise-incentive-based smoking cessation program as one of the workplace health promotion program. The aim of this study is to evaluate the program offered in an electronics company in Korea. A total of 109 electronics company employees were recruited. Participants were surveyed for smoking history, nicotine dependence, and job stress. They received smoking cessation education and were provided with a stepwise fitness center ticket. Of 109 participants, 58 (53.2%) successfully ceased smoking for 3 months. Significant differences between success and fail groups were apparent in cigarettes smoked per day (P = .002) and nicotine dependence score (P = .049). However, there was no significant difference in job stress between success and fail groups. Based on multiple logistic regression analysis, there were no identifiable factors associated with smoking cessation. In conclusion, a stepwise exercise-incentive-based smoking cessation program was highly effective when applied in a workplace setting.

We demonstrate an active metamaterial device that allows to electrically control terahertz transmission over more than one order of magnitude. Our device consists of a lithographically defined gold nano antenna array fabricated on a thin film of vanadium dioxide (VO(2)), a material that possesses an insulator to metal transition. The nano antennas let terahertz (THz) radiation funnel through when the VO(2) film is in the insulating state. By applying a dc-bias voltage through our device, the VO(2) becomes metallic. This electrically shorts the antennas and therefore switches off the transmission in two distinct regimes: reversible and irreversible switching., (© 2011 Optical Society of America)

This study has been focused on developing a cellulose pretreatment process using 1-n-butyl-3-methylimidazolium chloride ([bmim]Cl) for subsequent hydrolysis over Nafion(R) NR50. Thus, several pretreatment variables such as the pretreatment period and temperature, and the [bmim]Cl amount were varied. Additionally, the [bmim]Cl-treated cellulose samples were characterized by X-ray diffraction analysis, and their crystallinity index values including CI(XD), CI(XD-CI) and CI(XD-CII) were then calculated. When correlated with these values, the concentrations of total reducing sugars (TRS) obtained by the pretreatment of native cellulose (NC) and glucose produced by the hydrolysis reaction were found to show a distinct relationship with the [CI(NC)-CI(XD)] and CI(XD-CII) values, respectively. Consequently, the cellulose pretreatment step with [bmim]Cl is to loosen a crystalline cellulose through partial transformation of cellulose I to cellulose II and, furthermore, the TRS release, while the subsequent hydrolysis of [bmim]Cl-treated cellulose over Nafion(R) NR50 is effective to convert cellulose II to glucose., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The nonpulsatile blood flow obtained using standard cardiopulmonary bypass (CPB) circuits is still generally considered an acceptable, nonphysiologic compromise with few disadvantages. However, numerous reports have concluded that pulsatile perfusion during CPB achieves better multiorgan response postoperatively. Furthermore, pulsatile flow during CPB has been consistently recommended in pediatric and high-risk patients. However, most (80%) of the total hemodynamic energy generated by a pulsatile pump is absorbed by the components of the extracorporeal circuit and only a small portion of the pulsatile energy is delivered to the patient. Therefore, we considered that optimizations of CPB unit and extracorporeal life support (ECLS) system circuit components were needed to deliver sufficient pulsatile flow. In addition, energy equivalent pressure, surplus hemodynamic energy, and total hemodynamic energy, calculated using pressure and flow waveforms, were used to evaluate the pulsatilities of pulsatile CPB and ECLS systems.

Conversion of carbon dioxide (CO2) using gliding arc plasma was performed. The research was done to investigate the effect of variation of total gas flow rates and addition of auxiliary gases--N2, O2, air, water--to the CO2 conversion process. This system shows higher power efficiency than other nonthermal plasma methods. Experiment results indicate the conversion of CO2 reaches 18% at total gas flow rate of 0.8 L/min and produces CO and O2 as the main gaseous products. Among auxiliary gases, only N2 gives positive effect on CO2 conversion and the power efficiency at N2 concentration of 95% and total gas flow rate of 2 L/min increases about three times compared to pure CO2 process.

Decomposition of chlorinated hydrocarbons, CCl4 and CHCl3, in gliding plasma was examined. The effects of initial concentrations, total gas flow rates, and power consumption have been investigated. The conversion result was relatively high. It reached 80% for CCl4 and 97% for CHCl3. Using atmospheric air as the carrier gas, the plasma reaction occurred at exothermic reaction and the main products were CO2, CO, and Cl2. Transformation into CCl4 was also detected for CHCl3 decomposition reaction. The conversion of CCl4 and CHCl3 were increased with the increasing applied frequency and decreasing total gas flow rate.

The purpose of this study is to present the information on the duration of treatment and the cost of work-related low back pain. Using the compensation-database for 1997 work-related low back pain (n=9,277), this study estimated the duration of treatment, the cost of work-related low back pain, the relationship between them, and probability of being off treatment at different intervals. The mean and the median of the treatment duration are 252.6 days and 175 days. The mean and the median of the cost of total insurance benefit are 37,700,000 won and 14,400,000 won. The treatment duration of 51% of the study subjects was less than 6 months and their cost accounted for 10.2% of the total insurance benefit. The subjects who were treated more than 24 months were 5.8% but it accounted for 29.2% of the cost. It was found that approximately 50% of the subjects who will remain on treatment at the end of n months would be off treatment at the end of n+5 months. This study presents the point in time when the low back pain (LBP) workers need to prepare to return to work by forecasting their off-treatment period. From the treat duration and cost perspectives, this study may be utilized as evidence for active management of work-related LBP.