• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.3
• /
• pp.710-721
• /
• 1999

This study was conducted to investigate the hematological characteristics and risk factors of hypercholesterolemia(HC) in Korean. 344 adult men who took the annual health check ups at D or J hospitals were participated in this cross sectional study. The subjects were grouped by plasma total cholesterol level into three groups: normal cholesterolemic(n=139), borderline hypercholesterolemic (n=93) and hypercholesterolemic(n=112) groups. The data of systolic and diastolic blood pressure (SBP/DBP), hemoglobin, plasma glucose, albumin and cholesterol levels were collected from medical records. The levels of plasma triglyceride(TG), HDL C, phospholipid, insulin, apo A and apo B were measured. The levels of plasma LDL C, VLDL C and atherogenic index(AI) were calculated. The subjects with HC had significantly higher SBP and DBP, albumin, TG, phospholipid, HDL C, LDL C, VLDL C and apo B level than those of the normal subjects. The relative and attributable risks on HC were 1.59 and 0.18 for hypertension(SBP/DBP$\geq$160/95), 2.08 and 0.35 for hypertriglyceridemia (TG $\geq$400mg/dl). Plasma total cholesterol level was positively correlated with several hematologic parameters: age(r=0.1242, p<0.05), DBP(r=0.1194, p<0.05), albumin(r=0.2029, p<0.001), plasma TG(r= 0.3829, p<0.001), phospholipid(r=0.6036, p<0.001), LDL C(r=0.8572, p<0.001), HDL C(r=0.2399, p< 0.001), AI(r=0.3116, p<0.001), apo B(r=0.2602, p<0.05) and Lp(a)(r=0.1372, p<0.05). However, plasma total cholesterol level was negatively correlated with the levels of Apo A1(r= 0.2922, p<0.001), and ABR(r= 0.3598, p<0.001).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.15 no.10 s.89
• /
• pp.969-976
• /
• 2004

The wide and growing use of cellular phones has raised the question about the possible health risks associated with radio-frequency electromagnetic fields. It would be helpful for phone users to blow the exposure levels during cellular phone use. But it is very difficult to recognize the amount of exposure, because measuring accurate level of RF is a difficult matter. In this study, we developed a model to estimate the exposure level and the individual risk of exposure by utilizing the available informations that we can get. We used such parameters as usage time a day, total using period, distance between cellular phone and head, slope of cellular phone, hands-free usage, antenna pulled out or not SAR(Specific Absorption Rate) of cellular phone, and flip or folder type. We proposed a model presenting individual risk of RF exposure from level 0 to 10 by using a neural network.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.12 no.7
• /
• pp.1199-1205
• /
• 2001

There has been an increase in the public concern about possible health risks by electromagnetic exposure from mobile phones. Recently, several SAR measurement procedures have been proposed to demonstrate the compliance of mobile phone with safety limits. To determine the maximum localized SAR of a test mobile phone, the electric field distribution is measured in the head phantom with simulated tissue liquid using the probe The important parameters in SAR measurement are the E-field probe, the shape and size of phantom, the electrical parameters of simulated tissue liquid, and test position, etc. Therefore, in order to setup the measurement standard, the studies on these factors are required. In this paper, the effects of the maximum localized SAR on the test positions of mobile phones were analyzed by the numerical computation and the SAR measurement. From the results, the worst condition of commonly used positions was determined and the touch and tilted positions were adopted as test positions of the domestic SAR measurement standard.

• Journal of electromagnetic engineering and science
• /
• v.16 no.2
• /
• pp.87-99
• /
• 2016

This paper describes an implementation method and the results of numerical mobile phone models representing real phone models that have been released on the Korean market since 2002. The aim is to estimate the electromagnetic absorption in the human brain for case-control studies to investigate health risks related to mobile phone use. Specific absorption rate (SAR) compliance test reports about commercial phone models were collected and classified in terms of elements such as the external body shape, the antenna, and the frequency band. The design criteria of a numerical phone model representing each type of phone group are as follows. The outer dimensions of the phone body are equal to the average dimensions of all commercial models with the same shape. The distance and direction of the maximum SAR from the earpiece and the area above -3 dB of the maximum SAR are fitted to achieve the average obtained by measuring the SAR distributions of the corresponding commercial models in a flat phantom. Spatial peak 1-g SAR values in the cheek and tilt positions against the specific anthropomorphic mannequin phantom agree with average data on all of the same type of commercial models. Second criterion was applied to only a few types of models because not many commercial models were available. The results show that, with the exception of one model, the implemented numerical phone models meet criteria within 30%.

• The Korean Journal of Pain
• /
• v.33 no.3
• /
• pp.267-274
• /
• 2020

Background: General anesthesia (GA) has been considered the anesthetic technique which most frequent leads to phantom limb pain (PLP) after a limb amputation. However, these prior reports were limited by small sample sizes. The aims of this study were to evaluate the incidence of PLP according to the various anesthetic techniques used for limb amputation and also to compare the occurrence of PLP according to amputation etiology using the Korean Health Insurance Review and Assessment Service for large-scale demographic information. Methods: The claims of patients who underwent limb amputation were reviewed by analyzing the codes used to classify standardized medical behaviors. The patients were categorized into three groups-GA, neuraxial anesthesia (NA), and peripheral nerve block (PNB)-in accordance with the anesthetic technique. The recorded diagnosis was confirmed using the diagnostic codes for PLP registered within one year after the limb amputation. Results: Finally, 7,613 individuals were analyzed. According to the recorded diagnoses, 362 patients (4.8%) developed PLP after amputation. Among the 2,992 patients exposed to GA, 191 (6.4%) were diagnosed with PLP, whereas 121 (4.3%) of the 2,840 patients anesthetized with NA, and 50 (2.8%) of the 1,781 patients anesthetized under PNB developed PLP. The relative risks were 0.67 (95% confidence interval [CI], 0.53-0.84; P < 0.001) for NA and 0.43 (95% CI, 0.32-0.59; P < 0.001) for PNB. Conclusions: In this retrospective cohort study, using large-scale population-based databases, the incidence rates of PLP after limb amputations were, in the order of frequency, GA, NA, and PNB.

• The Journal of Engineering Geology
• /
• v.16 no.4 s.50
• /
• pp.351-357
• /
• 2006

Recently there is increasing the flow of hazardous chemical substances caused by industrial waste waters into a main river. It is needed to make the high treatment in drinking water treatment plants for reducing a health risk. Therefore, the monitoring of trace hazardous chemical substances by the industrial waste water inflow is available increasing economical efficiency of river management as well as reduction of risk. In this study, the most important substance among numerical and quantitative trace hazardous chemicals is Hexachlorobutadiene in an effluent of industrial wastes. However all items of GroupII which was included with semiconductor, electricity/electron and metal assemble was not detected. It means that we must consider the characteristics and behavior of load pollutants to water resources to select monitoring items. That was called 'preparatory monitoring'. We can reduce an economical consumption as well as risks from these pollutants using the preparatory monitoring.

• Environmental Analysis Health and Toxicology
• /
• v.25 no.3
• /
• pp.223-228
• /
• 2010

Neocaridina denticulata is a small freshwater shrimp indigenous to Korea. As an indigenous species has long-adapted to particular water environments, the species can be a suitable indicator to assess environmental risks caused by hazard chemicals in the particular site. Thus Neocaridina denticulata, a small freshwater shrimp indigenous to Korea, is worth considering for a test species for such purpose. N. denticulata were exposed to pentachlorophenol sodium salt, sodium azide and potassium dichromate using automatic flow-through system for 96 hours. The 96 hr lethal concentrations ($LC_{50}$) of these chemicals were calculated as $0.53{\pm}0.09\;mg/L$, $2.40{\pm}0.61\;mg/L$ and $1.21{\pm}0.09\;mg/L$ respectively and showed relatively small deviation from repetitive test results. When compared with the toxicity values of other species for each chemical, N. denticulata had moderate or high sensitivity to the toxicity of these chemicals. It can be concluded that N. denticulata is a good test species to evaluate acute toxicity of various hazardous chemicals.

• Environmental Engineering Research
• /
• v.19 no.3
• /
• pp.269-274
• /
• 2014

On-site sanitation systems are typically installed to treat grey and toilet wastewaters in areas without sewer and centralized treatment systems. It is well known that, due to inappropriate design and operation, treatment performance of these systems in developing countries is not satisfactory in the removal of pathogens and organic matters. This research aimed to investigate the hydraulic conditions occurring in some on-site sanitation systems and the effects of hydraulic retention times (HRTs) on the system performance. The experiments were conducted with a laboratory-scale septic tank (40L in size) and an actual septic tank (600L in size), to test the hydraulic conditions by using tracer study with HRTs varying at 12, 24 and 48 hr. The experimental results showed the dispersion numbers to be in the range of 0.017-0.320 and the short-circuit ratios in the range of 0.014-0.031, indicating the reactors having a high level of sort-circuiting and approaching complete-mix conditions. The removal efficiency of $BOD_5$ was found to be 67% and the $k_{30}$ values for $BOD_5$ was $2.04day^{-1}$. A modified complete-mix model based on the relationship between $BOD_5$ removal efficiencies and HRTs was developed and validated with actual-scale septic tank data having a correlation coefficient ($R^2$) of 0.90. Therefore, to better protect our environment and minimizing health risks, new generation toilets should be developed that could minimize short-circuiting and improving treatment performance.

• Journal of the Korean Society of Safety
• /
• v.23 no.6
• /
• pp.14-20
• /
• 2008

A large number of accidents have been occurred in the domestic shipbuilding industry. Its number of accidents is approximately twice than that of manufacturing industry and three times larger than that of whole industry in general. There are several reasons that make it hard to control the accidents. First, it is because the shipbuilding industry is composed of many subcontractors who may need improvement in safety education and safety management. Second, the shipyard environments are exposed to lots of hazards such as high elevation works, isolated workspaces, heavyweight and huge structures/components. Last, the shipbuilding industry has grown too rapidly in a short period. For that reason, the safety management standards and safety consciousness could not catch up the speed of its development. In this study, it is suggested to use a more efficient and easier way to conduct safety management using a web-based safety management system for the shipbuilding industry. This system is composed of four main parts, which is available for self-auditing with legal support. Those are checklists based safety and health evaluation, safety inspection, user shared accident database and user shared bulletin board. It is expected that this system can help us to reduce risks in the shipbuilding industry considerably.

• Journal of Nutrition and Health
• /
• v.35 no.10
• /
• pp.1081-1088
• /
• 2002

Flavonoids are phytochemicals that occur ubiquitously in plant foods that have been reported to have potential roles in the prevention of cancer, inhibition of platelet aggregation or inflammation. However, there was no accurate data reported on the intake of middle-aged Korean population. The present study was designed to assess dietary intake of flavonoids (including isoflavones) of 304 adults (20-59 yr, male 115, famale 189) living in Daejeon area using semi-quantitative food frequency questionnaire. The questionnaire consisted of 50 food items, including vegetables, soy products, seaweeds, nuts and beans, fruits and beverages. Our self-administered questionnaire contained questions regarding subject's habitual diet and alcohol intake over the previous 3 months. Average daily intake of individual flavonols such as quercetin, kaempferol, myricetin, and flavones such as luteolin, apigenin was 15.7, 8.7, 0.21, 2.07, 0.03 mg/day, respectively. Daily intake of daidzein and genistein, which are the commonly found isoflavones in soy products, were 16.6 and 21.4 mg/day, respectively. Combined intake of flavonoids was 64.3 mg/day. No effect of smoking, drinking and exercise was observed on flavonoids consumption. Food items that has the highest daily intake of each compounds were; quercetin (onion, 9.49 mg/day), kaempferol (strawberry, 1.18 mg/day), myricetin (green tea, 0.81 mg/day), apigenin (lettuce, 0.03 mg/day), luteolin (onion, 0.05 mg/day), daidzein (soybean sprout, 5.99 mg/day), genistein (soybean sprout, 7.02 mg/day). These findings provide valuable information on understanding the dietary flavonoids intake from a typical Korean daily diet, which might help to identify the risks for developing various diseases.