Joint Association of Change in Physical Activity and Sitting Time with Metabolic Syndrome Risk: A Prospective Cohort Study.

Background and Aims: The purpose of this study was to investigate the combined impact of variations in physical activity (PA) and sitting time (ST) on the risk of developing metabolic syndrome (MetS). Methods: This study was conducted on a cohort of adults from the general population, aged 40-69 years, who participated in the KOGES community-based cohort study over a span of 10 years. Changes in PA and ST were assessed using the results from PA questionnaires completed during baseline and follow-up surveys. The diagnosis of MetS was determined according to the criteria established by the International Diabetes Federation. To evaluate the combined effect of PA and ST changes on the incidence of MetS, we calculated hazard ratios and 95% confidence intervals using a Cox proportional hazards regression model. Result: The incidence of MetS was reduced by 39% (HR = 0.61, 95% CI = 0.46-0.82) for increased ST/increased PA and 26% (HR = 0.74, 95% CI = 0.58-0.94) for decreased ST/increased PA, compared with increased ST/decreased PA, respectively. In addition, this study confirmed that the combined impact of changes in PA and ST, based on the domain of PA, on the incidence of MetS varied. Conclusion: Changes in ST and PA are associated with the risk of developing MetS. These findings lay the groundwork for further research on the relationship between changes in PA, ST, and the occurrence of diseases.

Comparison of Absolute and Relative Grip Strength to Predict Incidence of Diabetes Mellitus in Korea: A Prospective Cohort Study.

Background: This study aimed to investigate the association between absolute grip strength (AGS), relative grip strength (RGS) levels, and the risk of developing diabetes in middle-aged adults, utilizing longitudinal data. Methods: A total of 1935 participants, 51-81 years of age, were engaged in surveys both in 2017-2018 and during the subsequent follow-up survey in 2019-2020. Diabetes diagnosis and treatment were the criteria for categorizing individuals as "diabetic." Grip strength was measured using the JAMA-5030J1 equipment (SAEHAN, Korea), and AGS and RGS were also categorized into tertiles by gender. A proportional hazards Cox regression model was used to evaluate the relationship among AGS, RGS, and the risk of developing diabetes. Subsequently, we computed the hazard ratio (HR) and 95% confidence interval (95% CI) for the risk of developing diabetes. Results: After adjusting for various confounding variables, a significant reduction in diabetes risk was observed in the high grip strength group, adjusted for body mass index (RGS1) and body weight (RGS2), compared with the low RGS1 and RGS2 groups (RGS1 HR = 0.54, 95% CI = 0.36-0.80; RGS2 HR = 0.50, 95% CI = 0.34-0.73). However, there were no significant associations between AGS and diabetes risk. Furthermore, significant differences in the relationship among AGS, RGS levels, and the risk of developing diabetes were found across gender and insulin resistance levels. Conclusion: This study underscores the importance of RGS levels in predicting the incidence of diabetes, with AGS, RGS1, and RGS2 emerging as significant predictive indicators for assessing diabetes risk.

Comparison of Absolute and Relative Grip Strength to Predict Incidence of Metabolic Syndrome: Eight-Year Follow-Up Study in Korea.

Background: This study aimed to conduct an analysis of longitudinal study to investigate the association of absolute grip strength, and relative grip strength with incidence of metabolic syndrome. Materials and Methods: Participants who participated in the Korean Genome and Epidemiology Study, a chronic screening program conducted in Ahnseong-si, Gyeonggi-do, a primary survey conducted from 2013 to 2014 were selected. The presence of metabolic syndrome was classified using the standards of the International Diabetes Foundation following previous studies. Grip strength was measured using a JAMA 5030J1 (Saehan, Korea) and calculated the absolute grip strength and relative grip strength. To evaluate the relationship between the absolute grip strength, relative grip strength, and incidence of metabolic syndrome, independent hazard ratios (HRs) and 95% confidence intervals (CIs) for metabolic syndrome were calculated according to absolute and relative grip strength levels using a multivariate extended Cox regression model. Results: The incidence of metabolic syndrome was reduced by 38% (HR = 0.62, 95% CI = 0.43-0.88) for the high absolute grip strength group, compared to the low absolute grip strength group. Also, this study confirmed that the incidence of metabolic syndrome for mid relative grip strength and high relative grip strength groups were reduced by 27% (HR = 0.73, 95% CI = 0.55-0.98) and 55% (HR = 0.45, 95% CI = 0.32-0.64) respectively. Moreover, the incidence of metabolic syndrome was reduced by 45% (HR = 0.55, 95% CI = 0.37-0.82) and 57% (HR = 0.43, 95% CI = 0.29-0.65) for the low-level body mass index (BMI) group with high or low absolute grip strength, respectively. Finally, this study confirmed the association of sex, absolute grip strength, and relative grip strength according to age with incidence of metabolic syndrome was different. Conclusion: We observed that relative grip strength has a higher association with incidence of metabolic syndrome than absolute grip strength. Also, BMI has a higher association with metabolic syndrome than the absolute grip strength.

Performance and economic efficiency analysis of an integrated, outdoor fan-ventilated cooling device.

Recently, the importance of mechanical facilities in charge of the safety and comfort of occupants in buildings has once again been highlighted in accordance with global social issues such as the spread of COVID-19. In response, various ventilation systems are being developed to improve indoor air quality, and efforts are being made to satisfy the indoor comfort of the occupants. Such advanced facilities allow occupants to secure indoor air quality, while frequent ventilation systems can affect the cooling and heating load in the building, and there is also a problem that it can occupy a relatively large amount of space in the building. This study proposes an integrated, outdoor fan-ventilated cooling device and analyzes its performance and economic efficiency. The EnergyPlus simulation program was used to model two types of systems for comparison: an existing (base) model with a condenser located in the outdoor unit, and a developed model with the condenser integrated within the cooling system. The state of the air passing through the condenser was analyzed prior to comparing the efficiency of the integrated, outdoor fan-ventilated cooling device, followed by an in-depth analysis of the performance and economic efficiency based on total energy consumption. In Case 1, the air passing through the cooling system was approximately 5  °C lower than the base model and showed 11% peak load reduction in comparison to the maximum energy consumption. Additionally, a comparison between regions with different outdoor air temperatures showed an average cost reduction of 16% in Daejeon and Busan City.

Relationship Between Relative Grip Strength and Serum Total Cholesterol, High-Density Lipoprotein Cholesterol, Low-Density Lipoprotein Cholesterol, and Triglyceride Levels in Korean Middle-Aged or Older Adults: A Panel Regression Model.

Background: This study aimed to conduct panel data analysis to investigate the effects of relative grip strength on blood lipid levels according to sex and obesity levels in adults living in South Korea Methods: A total of 1015 middle-aged or older adults (40-94 years old), who participated in a chronic screening program conducted in Yangpyeong, Gyeonggi-do from 2007 to 2015, were included in this study. Grip strength was measured using a TKK-5401 dynamometer (Takei, Japan), and relative grip strength was calculated by dividing the absolute grip strength by body mass index (BMI, kg/m2). Blood lipids analyzed in this study included serum triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Random effect panel regression analysis was conducted to evaluate ß values and 95% confidence intervals to investigate the independent effects of relative grip strength on blood lipid levels. Results: After adjusting for confounding variables, higher relative grip strength was associated with lower TG (ß = -34.68, P < 0.001), TC (ß = -8.47, P = 0.014), and LDL-C (ß = -8.19, P = 0.012), and higher HDL-C (ß = 6.70, P < 0.001). After additionally adjusting for BMI to evaluate the relationship between relative grip strength and blood lipid levels by obesity index, relative grip strength was only significantly associated with HDL-C (ß = 5.03, P < 0.001). However, after adjusting for waist circumference, relative grip strength was significantly correlated with all blood lipid levels (TG: ß = -33.31, P < 0.001; TC: ß = -8.04, P = 0.021; LDL-C: ß = -7.96, P = 0.015; and HDL-C: ß = 6.73, P < 0.001). Differences in changes of blood lipid levels according to an increase in relative grip strength were observed about sex and obesity level. Conclusions: We observed that relative grip strength and blood lipid levels were associated, and increased muscular strength from regular resistance exercise could help to improve blood lipid levels in middle-aged or older adults.

Developing energy based benchmark model and detailed energy analysis through school statistical data and field surveys.

Approximately 20% of all school facilities, i.e., 7,980 buildings, are at least 40 years old in Korea. As the number of aged buildings is expected to rapidly increase, it is necessary to improve such facilities to protect safe learning environments and save energy. This study aims to develop the energy based benchmark model (EBBM) and utilization for energy saving in school. EBBM can be operated for school buildings, a category encompassing complex buildings with different systems and large gaps between them. To utilization of EBBM allows us to obtain knowledge from the school facility, in order to define and tune data driven analysis rules. Data driven energy analysis also allows ascertaining their expected energy consumption and estimating the possible saving systems by using the building energy flow chart. In this research, Korea education data-base was analyzed to classify energy based benchmark model. Applicability review is conducted through detailed system analysis of 10 schools. The difference between the benchmark model calculated value and the actual value was confirmed to be within 10%. Through the benchmarking model, it is possible to compare energy consumption for buildings of different sizes. Energy consumption by energy source and room type was analyzed through an in-depth status survey. Most of School Classrooms consume the largest amount of energy, with cooling and heating energy constituting the largest proportion.

Workers' Exposure to Indium Compounds at the Electronics Industry in Republic of Korea.

OBJECTIVES: The aim of this study was to provide baseline data for the assessment of exposure to indium and to prevent adverse health effects among workers engaged in the electronics and related industries in Republic of Korea. METHODS: Total (n = 369) and respirable (n = 384) indium concentrations were monitored using personal air sampling in workers at the following 19 workplaces: six sputtering target manufacturing companies, four manufacturing companies of panel displays, two companies engaged in cleaning of sputtering components, two companies dedicated to the cleaning of sputtering target, and five indium recycling companies. RESULTS: The level of exposure to total indium ranged from 0.9 to 609.3 µg/m3 for the sputtering target companies; from 0.2 to 2,782.0 µg/m3 for the panel display companies and from 0.5 to 2,089.9 µg/m3 for the indium recycling companies. The level of exposure to respirable indium was in the range of 0.02 to 448.6 µg/m3 for the sputtering target companies; 0.01 to 419.5 µg/m3 for the panel display companies; and 0.5 to 436.3 µg/m3 for the indium recycling companies. The indium recycling companies had the most samples exceeding the exposure standard for indium, followed by sputtering target companies and panel display companies. CONCLUSIONS: The main finding from this exposure assessment is that many workers who handle indium compounds in the electronics industry are exposed to indium levels that exceed the exposure standards for indium. Hence, it is necessary to continuously monitor the indium exposure of this workforce and take measures to reduce its exposure levels.

A case of acute organic solvent poisoning during epoxy coating.

BACKGROUND: In the construction industry, maintaining health and safety of workers often challenging. Among the workers at construction sites, painters are at particular risk of respiratory diseases and neurotoxicity. However, in Korea there is weak enforcement of workers' health and safety practices in the construction industry in Korea. Poisonings frequently occur at (semi)closed construction sites. In this study, we report a case of acute organic solvent poisoning during construction site painting. CASE PRESENTATION: A 71-year-old man was found unconscious at a construction site and immediately transferred to the emergency room. The consciousness level was 'stupor state' and the body temperature was hypothermic, at 32 degrees (Celsius). There were no acute brain or cardiac lesions that would have accounted for the faintness. In addition, blood and urine tests did not indicate a cause of loss of consciousness. He had been painting epoxy to waterproof the basement floor before fainting. According to exposure simulation, the patient was overexposed to various organic solvents, such as approximately 316-624 ppm toluene during the work before fainting. Considering the ventilation status of the workplace and the status of no protection, it is considered that exposure through the respiratory tract was considerable. CONCLUSIONS: The patient in this case lost consciousness during the epoxy coating in a semi-enclosed space. It can be judged as a result of acute poisoning caused by organic solvent exposure and considered to be highly related to work environment.

Blood levels of cadmium and lead in residents near abandoned metal mine areas in Korea.

We analyzed national data on blood lead levels (BLL) and blood cadmium levels (BCL) in residents living near 38 abandoned metal mining areas (n = 5,682, 18-96 years old) in Korea that were collected by the first Health Effect Surveillance for Residents in Abandoned Metal mines (HESRAM) from 2008 to 2011. The geometric mean BCL and BLL were 1.60 µg/L (95 % CI = 1.57-1.62 µg/L) and 2.87 µg/dL (95 % CI = 2.84-2.90 µg/dL), respectively, notably higher than levels in the general population in Korea and other countries. We found significantly higher BLL and BCL levels in people living within 2 km of an abandoned metal mine (n = 3,165, BCL = 1.87 µg/L, BLL = 2.91 µg/dL) compared to people living more than 2 km away (n = 2,517, BCL = 1.31 µg/L, BLL = 2.82 µg/dL; P < 0.0001) and to the general population values reported in the literature.

A comprehensive review of arsenic levels in the semiconductor manufacturing industry.

This paper presents a summary of arsenic level statistics from air and wipe samples taken from studies conducted in fabrication operations. The main objectives of this study were not only to describe arsenic measurement data but also, through a literature review, to categorize fabrication workers in accordance with observed arsenic levels. All airborne arsenic measurements reported were included in the summary statistics for analysis of the measurement data. The arithmetic mean was estimated assuming a lognormal distribution from the geometric mean and the geometric standard deviation or the range. In addition, weighted arithmetic means (WAMs) were calculated based on the number of measurements reported for each mean. Analysis of variance (ANOVA) was employed to compare arsenic levels classified according to several categories such as the year, sampling type, location sampled, operation type, and cleaning technique. Nine papers were found reporting airborne arsenic measurement data from maintenance workers or maintenance areas in semiconductor chip-making plants. A total of 40 statistical summaries from seven articles were identified that represented a total of 423 airborne arsenic measurements. Arsenic exposure levels taken during normal operating activities in implantation operations (WAM = 1.6 µg m⁻³, no. of samples = 77, no. of statistical summaries = 2) were found to be lower than exposure levels of engineers who were involved in maintenance works (7.7 µg m⁻³, no. of samples = 181, no. of statistical summaries = 19). The highest level (WAM = 218.6 µg m⁻³) was associated with various maintenance works performed inside an ion implantation chamber. ANOVA revealed no significant differences in the WAM arsenic levels among the categorizations based on operation and sampling characteristics. Arsenic levels (56.4 µg m⁻³) recorded during maintenance works performed in dry conditions were found to be much higher than those from maintenance works in wet conditions (0.6 µg m⁻³). Arsenic levels from wipe samples in process areas after maintenance activities ranged from non-detectable to 146 µg cm⁻², indicating the potential for dispersion into the air and hence inhalation. We conclude that workers who are regularly or occasionally involved in maintenance work have higher potential for occupational exposure than other employees who are in charge of routine production work. In addition, fabrication workers can be classified into two groups based on the reviewed arsenic exposure levels: operators with potential for low levels of exposure and maintenance engineers with high levels of exposure. These classifications could be used as a basis for a qualitative ordinal ranking of exposure in an epidemiological study.

Advanced korean industrial safety and health policy with risk assessment.

This article describes a systematic roadmap master plan for advanced industrial safety and health policy in Korea, with an emphasis on. Since Korean industries had first emergence of industrial safety and health policy in 1953, enormous efforts have been made on upgrading the relevant laws in order to reflect real situation of industrial work environment in accordance with rapid changes of Korean and global business over three decades. Nevertheless, current policy has major defects; too much techniques-based articles, diverged contents in less organization, combined enforcement and punishments and finally enforcing regulations full of commands and control. These deficiencies have make it difficult to accommodate changes of social, industrial and employment environment in customized fashion. The approach to the solution must be generic at the level of paradigm-shift rather than local modifications and enhancement. The basic idea is to establish a new system integrated with a risk assessment scheme, which encourages employers to apply to their work environment under comprehensive responsibility. The risk assessment scheme is designed to enable to inspect employers' compliances afterwards. A project comprises four yearly phases based on applying zones; initially designating and operating a specified risk zone, gradually expanding the special zones during a period of 3 years (2010-2012) and the final zone expanded to entire nation. In each phase, the intermediate version of the system is updated through a process of precise and unbiased validation in terms of its operability, feasibility and sustainability with building relevant infrastructures as needed.

A survey for rhinitis in an automotive ring manufacturing plant.

We report findings regarding otolaryngologist-confirmed rhinitis, current exposure to MWF aerosols, fungi, and endotoxins for workers in a plant manufacturing automobile piston rings. Questionnaire data showed that 61.5% of 187 workers exhibited rhinitis-related symptoms. Rhinitis was confirmed in 99 of 115 workers whom were medically examined. Otolaryngologist-confirmed rhinitis was present in 10 of 19 grinding workers (52.6%), 67 of 142 production workers (47.2%), and 22 of 26 quality control (QC) workers (84.6%). These rates are much higher than the rates of rhinitis-related symptoms in automobile plants and other occupational settings and quite high even allowing for the common occurrence of rhinitis in the general population. We found that rhinitis could develop even in workers exposed to less than 0.5mg/m(3) MWF aerosol. The average exposure to fungi exceeded 10 x 10(3) CFU/m(3), a level higher than that reported for other automobile plants. Although we were unable to identify significant risk factors for rhinitis using only the physician-confirmed rhinitis cases, this study concludes that exposure to MWF aerosol, which would include microbes and metals, could contribute to a high occurrence of rhinitis in grinding and production workers. Forty-nine workers (63.6%) of 77 rhinitis patients in grinding and production operations were determined to handle synthetic MWF directly. For QC workers, for whom the prevalence of physician-confirmed rhinitis was highest, exposure to a low level of MWF aerosol, including specific microbe species we couldn't identify, bright light, dry air, and certain work characteristics during inspection are possible risk factors for development of rhinitis. Further studies including identification of fungi species should be conducted so a firm conclusion can be made regarding the development of rhinitis in QC manufacturing plant workers.

Association between use of synthetic metalworking fluid and risk of developing rhinitis-related symptoms in an automotive ring manufacturing plant.

The main objective of this study was to determine the association between synthetic metalworking fluid (MWF) and rhinitis-related symptoms. At a plant manufacturing piston rings for automobiles, we interviewed grinders (19) and manufacturing workers (142) in operations where synthetic or semisynthetic MWF is handled, and administrative office workers (44) regarding the principal symptoms of rhinitis (nasal stuffiness, runny nose, anosmia, nasal itchiness, rhinorrhea, headache, epistaxis, and post-nasal drip). In addition, we assessed the current exposure of workers handling MWF to MWF aerosols, fungi, and endotoxins. Logistic regression analysis was used to examine the association between MWF surrogates indicative of MWF exposure and each rhinitis-related nasal symptom. Odds ratios (ORs) and 95% confidence intervals were adjusted for sex, age, smoking habit, and duration of employment. Among grinders handling synthetic MWF, the frequency of complaints of the dominant symptoms was 66.7% for nasal stuffiness, 77.8% for anosmia, 77.8% for runny nose, and 50.0% for headache. These rates are quite high even allowing for the common occurrence of rhinitis in the general population. Twenty eight of 34 grinding and manufacturing workers (82.4%) sampled were exposed to MWF mist above the threshold limit of 0.2 mg/m(3) listed as a notice of intended change by the American Conference for Governmental Industrial Hygienists (ACGIH). The percentage of workers exposed to MWF mist >0.5 mg/m(3) was 17.6%. Most workers were exposed to fungi levels >103 CFU/m(3). All exposures to endotoxins were <50 EU/m(3). Logistic regression analysis found that use of synthetic MWF was significantly associated with excess risk of nasal stuffiness (OR 3.5), nasal itchiness (OR 2.0), and runny nose (OR 2.1). The use of semi-synthetic MWF had little or no impact on the risk of developing rhinitis-related nasal symptoms. Grinding workers handling synthetic MWF had an increased risk of nasal stuffiness (OR 7.9), anosmia (OR 23.2), nasal itchiness (OR 8.3), runny nose (OR 20.4), post nasal drip (OR 18.4), and headache (OR 7.4) compared to administrative workers. Synthetic MWF may play an important role in the development of the dominant symptoms of rhinitis. Further study is needed to establish the risk of rhinitis or rhinitis-related symptoms according to MWF type.