• Fashion & Textile Research Journal
• /
• v.2 no.5
• /
• pp.411-415
• /
• 2000

To be able to work safely and efficiency, the Threshold Limit Values (TLV) for work in the heat are widely used. Since these TLV are only applicable to workers in regular clothing, TLV should be adjusted when applied to the asbestos removal workers who wear extra impermeable protective clothing. Although abbreviated guidelines for heat stress exposure have been proposed, literature advocating their use in the asbestos removal industry is limited. Therefore, we planed a survey to evaluate the workload of asbestos abatement workers in summer, and an experiment with climatic chambers to evaluate the effects of resting in a cool environment between work periods. From these studies, we got following conclusions. There is a high risk of suffering from heat illness by asbestos abatement work in summer in Japan. It is proposed to create a cool room inside the workplace of asbestos abatement work to reduce thermal stress.

• Journal of Nutrition and Health
• /
• v.40 no.3
• /
• pp.211-220
• /
• 2007

The purpose of this study was to investigate that the effect of dietary fatty acid composition on pro- and macro-glycogen utilization and resynthesis. The analyses were further extended for different muscle fibers (type I, type II, & type IIb) as well as tissues (i.e., liver & heart). Total one hundred sixty Sprague-Dawley rats were used, and rats were randomly allocated into four experimental groups: animals fed standard chow diet (n=40), animals fed saturated fatty acid diet (n=40), animals fed monounsaturated fatty acid (n=40), and animals fed polyunsaturated fatty acid (n=40). Animals in each groups were further divided into five subgroups: sacrificed at REST (n=8), sacrificed at immediately after 3 hr swim exercise (P-0HR, n=8), sacrificed at one hour after 3 hr swim exercise (P-1HR, n=8), sacrificed at four hour after 3 hr swim exercise (P-4HR, n=8), and sacrificed at twenty-four hour after 3 hr swim exercise (P-24HR, n=8). Soleus (type I), red gastrocnemius (type IIa), white gastrocnemius (type IIb), liver, and heart were dissected out at appropriated time point from all animals, and were used for analyses of pro- & macro-glycogen concentrations. After 8 weeks of dietary interventions, there was no significant difference in body mass in any of dietary conditions (p>.05). After 3 hr swim exercise, blood lactate level was higher compared to resting conditions in all groups, but it was returned to resting value after 1 hr rest (p<.05). Free fatty acid concentration was higher in all high fat fed groups(regardless of fatty acid composition) than CHOW consumed group. At rest, pro- & macro-glycogen concentration was not different from any of experimental groups (p>.05). Regardless of forms of glycogen, the highest level was observed in liver (p<.01), and most cases of supercompensation after 3hr exercise observed in this study were occurred in CHOW fed tissues. Except heart muscle, all tissues used in this study showed that pro- and macro-glycogen concentration was significantly decreased after 3 hr exercise. Based on these results, two conclusions were made: first, there is no different level of glycogen content in various tissues regardless of types of fatty acids consumed and second, the highest mobilization rate would be demonstrated from CHOW fed animals compare to animals that consumed any kinds of fatty acid diet if prolonged exercise is applied.

• Advances in pediatric surgery
• /
• v.20 no.2
• /
• pp.48-52
• /
• 2014

Purpose: Currently the substantial clinical benefits of single-port laparoscopic appendectomy (SLA) over conventional three-port laparoscopic appendectomy (CLA) are equivocal. The aim of this study was to compare surgical outcomes between SLA and CLA in children with acute appendicitis. Methods: A single blind prospective randomized single center study was performed to compare the surgical outcomes of SLA and CLA. A total of 105 patients were randomized and various parameters were analyzed, 52 patients with SLA and 53 patients with CLA between July 2013 and March 2014. Patients with sonographically confirmed acute appendicitis were randomly assigned to receive either SLA or CLA. The outcome measurements were operating time, wound complication, and intraperitoneal morbidities, postoperative pain score and cosmetic result score. Results: Operating time is significantly longer in SLA ($70.4{\pm}26.7$ minutes vs. $58.0{\pm}23.4$ minutes; p=0.016). There were no significant differences in the postoperative wound complication rate and intraperitoneal morbidities between two groups. There were no significant differences in postoperative resting pain score ($6.6{\pm}2.5$ vs. $6.3{\pm}2.5$; p=0.317) and activity pain score ($6.9{\pm}2.4$ vs. $6.3{\pm}2.5$; p=0.189), and the cosmetic result score ($9.2{\pm}1.1$ vs. $9.1{\pm}1.4$; p=0.853). Conclusion: Although SLA would be a safe and feasible procedure in children, SLA could not demonstrate the clear benefit over CLA.

• The Korean Journal of Physiology
• /
• v.27 no.2
• /
• pp.209-215
• /
• 1993

The aim of the present study was to derive regression equations for $\dot{V}o_{2max}\;vs.\;\dot{V}o_{2peak},\;and\;\dot{V}o_2\;vs.$ heart rate, exercise time, and other variables from maximal exercise tests on a treadmill using the Bruce and inclined protocols. Twelve male and 10 female Korean college students aged between 19 and 23 years voIunteered for this study. After the resting measurements, the subjects performed a maximal exercise on a treadmill according to the Bruce protocol. When the resting conditions were restored, the subjects performed another maximal exercise according to an inclined protocol where the speed was fixed at 8.05 $km{\cdot}h^{-1}$ and the grade was incremented starting from 09t by 2.5% for every 2 min. Peak $\dot{V}o_2$ observed during the Bruce exercise $(\dot{V}o_{2peak})$ was $37.7{\pm}2.4\;and\;31.7{\pm}1.8\;ml\;kg^{-1}\;min^{-1}$ in the male and female groups, respectively. Peak $\dot{V}o_2$ observed during the inclined exercise was higher than $\dot{V}o_{2peak}$ during the Bruce exercise. Maximum $\dot{V}o_2$ value observed during the tyro exercises $(\dot{V}o_{2max})$ was $43.0{\pm}2.8\;and\;36.2{\pm}1.4\;ml\;kg^{-1}\;min^{-1}$ in the male and female groups, respectively. Thus, $\dot{V}o_{2peak}$ by the Bruce protocol was about 12% (male) or 13% (female) lower than $\dot{V}o_{2max}$, and a linear relationship was found between $\dot{V}o_{2peak}$ and $\dot{V}o_{2max}$. The peak values of % $\dot{V}o_{max}$ with the Bruce protocol were $89.2{\pm}3.3\;and\;87.5{\pm}3.6%$ and those with the inclined protocol $97.7{\pm}1.8\;and\;96.9{\pm}2.0%$ in the male and female groups, respectively. In the female group, $%\dot{V}o_{2max}$ at a given workload was higher than in the male group, while $\dot{V}o_{2}$ per kg body weight was the same. Maximum HR observed during the two exercises was $204{\pm}2\;and\;195{\pm}3\;beat\;min^{-1}$ in the male and female groups, respectively. Linear relationships were found, excluding the last points, between 1) $\dot{V}o_{2}$ and exercise time, 2) $\dot{V}o_{2}$ and $%\dot{V}o_{2max}\;and\;%HR_{max}$.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.4
• /
• pp.1175-1184
• /
• 2018

The purpose of this study was to investigate effects of 12-weeks finswimming exercise on electroencephalogram(EEG), SBP, DBP, and RHR in male adolescents. Eighteen male adolescents participated in this study. They were separated into a Control group(CG; n=9) and Finswimming training group(FG; n=9). FG participated in Finswimming training for 12weeks, 60 minutes per day, 3 times a week. All data of electroencephalogram were analyzed by repeated measures two-way ANOVA and Data of SBP, DBP and RHR were analyzed by ANCOVA and Paired t-test. As a result, Alpha and SMR waves were significantly increased in FG; however, Alpha wave was significantly decreased in CG and Theta wave was significantly decreased in FG. There were significant interaction in Alpha, Theta, and SMR waves. SBP, DBP, and RHR were significantly decreased in FG and there were significant differences of RHR and SBP between groups; otherwise, there were no significant differences of DBP between groups. The results of this study showed that 12 weeks of Finswimming training positively effects on electroencephalogram(EEG), SBP, DBP, and RHR in male adolescents.

• Journal of the Institute of Convergence Signal Processing
• /
• v.16 no.2
• /
• pp.50-55
• /
• 2015

The noise of MRI shooting is 100dB loud and has an intensive psychological and physiological influences on the human body. ECG signals were measured by experimental methods, while wearing earplugs for 15 minutes in the stable state. Then the ECG signals were measured for 30 minutes while listening to about 100dB of sound in a MRI equipment. In this study, the heart rate variability of men and women was analyzed according to the MRI noise stress level through the frequency analysis. As the MRI noise level is about 100dB, HRV analysis resulted in an imbalance between the sympathetic and parasympathetic. During the period from the resting state up to 10 minutes, the maximum stress state was shown. This study will encourage MRI workers to take interests in hearing protection for the patient and to make objective indicators about MRI noises.

• Aerospace Engineering and Technology
• /
• v.8 no.1
• /
• pp.207-214
• /
• 2009

The purpose of this study was to examine the influence of hypoxic exercise at head down tilt (HDT) on cardiovascular responses. Eight men ($23{\pm}2$ yrs, $176{\pm}4$ cm, and $75{\pm}8$ kg) underwent four separate exercise testing sessions; seated normoxia (SN), seated hypoxia (SH), HDT normoxia (HN), and HDT hypoxia (HH). Each participant performed the leg cycling at predetermined 40% of maximal aerobic capacity relevant to each posture for 15 min. Heart rate was higher in SH than SN and higher also in HH than SH (p<0.05). Blood oxygen saturation was lower in SH than SN (p<0.05). During resting, diastolic blood pressure and mean arterial pressure was significantly lower in HDT than seated posture (p<0.05). No differences were found between conditions in hemoglobin and hematocrit and electrolytes including, sodium, potassium, and chloride. Lactate was higher in SH than SN. In conclusion, there was no effect for cardiovascular responses to duplicate stimuli both hypoxia and posture.

• Korean Journal of Rural Living Science
• /
• v.8 no.2
• /
• pp.111-117
• /
• 1997

In this study we tried to give a decision on propriety of working conditions, to present ideas on reducing work loads. and to grope for efficiency of agricultural works. For this we examined the actual conditions of working environment, farmer's clothes, working posture, working methods, working time, resting state, fatigue recovery methods during cultivating lettuce in the winter greenhouse. And Ive improved harmful factors that affect farmer's health by considering results of previous study and farmer's subjective sensation. And we measured, compared, and analyzed the farmer's work loads before and after improvement. The results of this study are as follows ; 1. According to examine the actual conditions of cultivating lettuce in the winter greenhouse, farmers have experienced physical and mental chronic fatigue on the basis of the hot and humid crops-centered working environment, the rough ground condition, inconsistent arrangement of working stand and sorter, heavy-weared habits. and unsuitable working posture. 2. When we improved harmful factors that affect farmer's health, conformed the positive effects on important work efficiency index such as heart rate, electromyovolume, body temperature, and microclimate inside clothing and work loads were decreased by improving the hot and humid working environment, eliminating the hillock and obstacles of working path. deliver way, arranging the working stand and sorter consistantly, decreasing the clothing weight, improving the working postures and methods as using assistant appliances, alloting the working time and sequence effectively and presenting the light gymnastic exercises and rest for fatigue restoration.

• Journal of Korean Biological Nursing Science
• /
• v.23 no.1
• /
• pp.22-30
• /
• 2021

Purpose: This descriptive study aimed to investigate heart rate variability (HRV) according to sex and to elucidate the influence of negative emotion such as levels of stress, anxiety and depression on HRV among Korean college students based on a neurovisceral integration model. Methods: A descriptive study design was used. Eighty-six healthy college students participated in the study. Resting HRV and standing HRV on orthostatic stimulation were measured for 5 minutes during 4-6 p.m. in the afternoon. Levels of stress, anxiety and depression were assessed using the Global assessment of recent stress, State-Trait Anxiety Inventory and Beck Depression Index, respectively. Results: Out of the 86 students, 47 (54.7%) were men and 39 (45.3%) were women. Root mean square of the differences between adjacent RR intervals (RMSSD) and normalized high frequency (nHF) on standing HRV were significantly lower in men than in women (p= .005, p= .019, respectively). Male gender (β= 0.30, p= .013), higher level of stress (β= -0.36, p= .009) and lower level of depression (β = 0.30, p= .044) exerted a significant influence on decreased nHF in the multiple regression analysis. Conclusion: We suggest that men are more vulnerable to having reduced vagal activity on HRV than women. Since male gender, higher level of stress and lower level of depression level influenced decreased vagal activity, strategies are needed to improve stress and depression rather than anxiety especially for men, which contribute to promoting HRV to prevent cardiac health diseases.

• The Korean Journal of Physiology
• /
• v.2 no.1
• /
• pp.53-58
• /
• 1968

In order to study the electrocardiogram of small animals authors deviced a fixing apparatus in the ventral resting position of rabbit and an attaching electrodes. Normal electrocardiograms of 8 adult rabbits were studied with author's improved fixing apparatus and electrodes. Leads taken were the standard limb lead, augmented unipolar leads and the unipolar precordial leads. The total numbers of various leads were eleven altogether. Results obtained in this study may be summarized as follows: 1. The details of the methods used to record and measure the six standard frontal plane leads and the five precordial leads of the rabbit electrocardiogram in the ventral resting position were described. The fixing apparatus of rabbits in ventral position are shown in Figure 1 and the attaching electrodes are shown in Figure 2. 2. The electrocardiographic changes in ventral position were more stable than in dorsal position in each lead. 3. The analysis of the amplitude, duration and other values of various waves are shown in Table 1 and Figure 3. 4. The electrocardiogram of rabbits showed decreased heart rate in ventral position than dorsal one. 5. The mean electrical axis of QRS complex in ventral position were +44.12 degrees and in dorsal position were +25.5 degrees.