• Journal of Chest Surgery
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• v.23 no.3
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• pp.452-464
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• 1990

It is well known that extracellular Calcium plays a very important role in several steps of smooth muscle excitability and contractility, and there have been many concerns about factors influencing the distribution of extracellular Ca++ and the Ca++ flux through the cell membrane of the smooth muscle. Based on the assumption that Mg++ may also play an important role in the excitation and contraction processes of the smooth muscle by taking part in affecting Ca++ distribution and flux, many researches are being performed about the exact role of Mg++, especially in the vascular smooth muscle. But yet the effect of Mg++ in the smooth muscle activity is not clarified, and moreover the mechanism of Mg++ action is almost completely unknown. Present study attempted to clarify the effect of Mg++ on the excitability and contractility in the multiunit and unitary smooth muscle, and the mechanism concerned in it. The preparations used were the guinea-pig aortic strip as the experimental material of the multiunit smooth muscle and the rat uterine strip as the one of the unitary smooth muscle. The tissues were isolated from the sacrificed animal and were prepared for recording the isometric contraction. The effects of Mg++ and Ca++ were examined on the electrically driven or spontaneous contraction of the preparations. And the effects of these ions were also studied on the K+ or norepinephrine contracture. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% 02 and kept at 35oC. The results obtained were as follows: 1] Mg++ suppressed the phasic contraction induced by electrical field stimulation dose-dependently in the guinea-pig aortic strip, while the high concentration of Ca++ never recovered the decreased tension. These phenomena were not changed by the a - or b - adrenergic blocker. 2]Mg++ played the suppressing effect on the low concentration [20 and 40 mM] of K+-contracture in the aortic muscle, but the effect was not shown in the case of 100mM K+-contracture. 3] Mg++ also suppressed the contracture induced by norepinephrine in the aortic preparation. And the effect of Mg++ was most prominent in the contracture by the lowest [10 mM] concentration of norepinephrine. 4] In both the spontaneous and electrically driven contractions of the uterine strip, Mg++ decreased the amplitude of peak tension, and by the high concentration of Ca++ the amplitude of tension was recovered unlike the aortic muscle. 5] The frequency of the uterine spontaneous contraction increased as the [Ca++] / [Mg++] ratio increased up to 2, but the frequency decreased above this level. 6] Mg++ decreased the tension of the low[20 and 40mM] K+-contracture in the uterine smooth muscle, but the effect did not appear in the 100mM K+-contracture. From the above results, the following conclusion could be made. 1] Mg++ seems to suppress the contractility directly by acting on the smooth muscle itself, besides through the indirect action on the nerve terminal, in both the aortic and uterine smooth muscles. 2] The fact that the depressant effect of Mg++ on the K+-contracture is in inverse proportion to an increase of K+ concentration appears resulted from the extent of the opening state of the Ca++ channel. 3] Mg++ may play a depressant role on both the potential dependent and the receptor-operated Ca++ channels. 4] The relationship between the actions of Mg++ and Ca++ seems to be competitive in uterine muscle and non-competitive in aortic strip.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.518-525
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• 2010

The purpose of the study was to examine health-related behaviors and nutrient intake in relation to job stress level of police officers. Total of 166 police officers working in Jeonbuk area participated in the study. The study was conducted from February to March, 2009. Subjects were given self-administered questionnaire on their general health status, dietary and health-related habits. Nutrient intake was assessed by semi-quantitative food frequency questionnaire. Subjects were divided into four groups (very low, low, high, very high) by their job stress level scores. Main concerns of job stress were from 'job demand', 'organizational system' and 'lack of reward'. More than 95% of the subjects were confident of their health status. Health habits, such as drinking, smoking and exercising, were better than that of average Korean men. There were significant differences in dietary habits in relation to job stress level. Lower job stress group showed lower rate of skipping breakfast (p<0.01), more affordable meal time (p<0.05) and better snacking habits (p<0.001). Sweet food preference was higher in lower job stress group (p<0.05). The average calorie intake was $2063\pm532.7$ (88.5% of EER) and there was no significant difference in nutrient intake among job stress levels. However, mean intake of calcium and vitamin $B_2$ was less than 75% of %DRI in higher job stress group. Therefore, further support in nutritional counseling programs to improve dietary behaviors and health habits and to reduce job concerned stress of the police officers will be necessary.

• Journal of the Korean earth science society
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• v.30 no.2
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• pp.196-209
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• 2009

Occurrences of sandstorms in the deserts and loess of Mongolia and northern China and associated dustfall episodes in the Korean Peninsula were monitored during the period January through December, 2005. False colour images were made by directly receiving the NOAA Advanced Very High Resolution Radiometer (AVHRR) data, and the distribution and transport of sandstorms were analyzed. The ground concentrations for PM10, PM2.5 and visibility of the dustfall episodes (PM10 concentration over $190{\mu}g\;m^{-3}$) were analyzed at Cheongwon, located midway in South Korea, and in the leeward direction of the place of origin of the sandstorms. Variations in the concentrations of $O_3,\;NO_2$, CO and $SO_2$ were also compared with dust concentrations in the dustfall episodes. Fewer occurrences of strong sandstorms in the place of origin were observed in 2005, due largely to the accumulation of snow and mild fluctuations of high and low pressure systems in the place of origin, thereby accounting for a low frequency of dustfall episodes in Korea, compared with those during the period 1997-2005. A total of 7 dustfall episodes were monitored in Korea in 2005 that lasted 11 days. In summer, sandstorms occurred less frequently in the source region in 2005 due to high humidity and milder winds, thereby causing no dustfall episodes in Korea. In case the sandstorms occurring at the place of source head directly to Korea without passing through large cities and industrial areas of China, the PM2.5 concentrations were measured at 20% or lower than the PM10 concentrations. However, when the sandstorms headed to Korea via the industrial areas of eastern China, where they pick up anthropogenic air pollutants, the PM2.5 concentrations were at least 25% higher of the PM10 concentrations. On the other hand, over 5 cases were observed and analyzed in 2005 where the PM10 concentrations of sand dust originating from the deserts were measured at $190{\mu}g\;m^{-3}$ or lower, falling short of the level of a dustfall episode.

• Journal of Life Science
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• v.22 no.7
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• pp.871-879
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• 2012

Polyploids are a potentially important germplasm source in seedless citrus breeding program. Seedlessness is one of the most promising traits of commercial mandarin breeds that mandarin triploid hybrids possess permanently. The formation of new constant triploid hybrids can be recovered through diploid species hybridization from the fusion of divalent gametes at low frequencyor intra-and inter-ploidy crosses. However, extensive breeding work based on small $F_1$ hybrid seeds developed is impossible without a very effective aseptic methodology and ploidy event. In this study, in vitro embryo culture was employed to recover natural hybrids from monoembryonic diploid, open-pollinated mandarin. Flow cytometry was used to determine ploidy level. A total of 10,289 seeds were extracted from 792 fruits having approximately 13 seeds per fruit. Average frequency of small seeds developed was 7.1%, while the average frequency of small seeds per fruit were: 8.9% for 'Clementine' 10.2% for 'Harehime' 2.6% for 'Kamja' 3.1% for 'Pyunkyool' 2.8% for 'Sadookam' and 7.0% for 'Wilking' mandarin. Average size of a perfect seed was $49.52{\pm}0.07mm^2$ ('Clementine') while the small seed measured $7.95{\pm}0.04mm^2$ ('Clementine'), which was about 1/6 smaller than the perfect seed. In total, 731 small seeds were obtained and all of them contained only one embryo per seed. The efficiency of 'Clementine' was 14 times higher than 'Wilking' and more than 109 times higher than 'Pyunkyool'. The basic information on spontaneous polyploidy provides for the hybridization of constant triploids and increases the efficiency of conventional cross.

• Geophysics and Geophysical Exploration
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• v.8 no.2
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• pp.145-155
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• 2005

A two-dimensional (2-D) interpretation of MT data has been performed for the purpose of fracture detection for geothermal development. Remote stations have been operated in Kyushu, Japan (480 km apart) as well as in Korea (60 km and 165 km apart in 2002 and 2003 data set, respectively). Apparent resistivity and phase curves calculated by remote processing with the Japan remote data showed enough quality for 2-D inversion for the whole frequency range. Remote reference processing with Korea remote reference data also showed quite good continuity in apparent resistivity and phase curves except some noisy frequency bands; around the power frequency, 60 Hz, and around the dead band $10^{-1}Hz\;Hz\;\~1\;Hz$, where the natural EM signal is known to be very weak. Even though the subsurface showed severe three-dimensional (3-D) characteristics in the survey area so that 2-D inversion by itself could not give enough information for deep geological structures, the 2-D inversion for the 5 survey lines showed several common features. The conductive semi-consolidate mudstone layer is dipping from north to south (about 500 m depth on the south and 200 m on the north most part of the survey area). The boundary between the low (L-2) and high (H-2) resistivity anomalies can be thought as a major fault with strike $N15^{\circ}E$, passing through the sites 206, 112 and 414. The shallow (< 1 km) conductive anomalies (L-4) seem to be fracture zones having strike E-W (at site 105) and $N60^{\circ}W$ (at site 434). And there exists a conductive layer in the western and west-southern part of the survey area in the depth below $2\~3\;km$, for which further investigation is to be needed.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.1
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• pp.7-15
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• 2000

To assess the accuracy of blood pressure measurement in general hospital nurses, 276 nurses at four hospital in Kyungju city and Pohang city were observed during the study period 20 December 1998 to 29 December 1998. The nurses measuring the blood pressure of simulated patient's were checked by the researcher or 20 items, that are recommended for consideration when doing a blood pressure measurement. Of the six items in the preparation step for measuring blood pressure, the accuracy of 'patients shouldn't talk during the procedure' had the lowest frequency(27.1%) and the other five items were above 80%. Of the ten items on blood pressure measuring technique, the accuracy of the frequency for 'inflating the cuff until the radial or brachial artery pulse is no longer palpable and then adding 30mmHg' was 0%, 'waiting $30{\sim}60$ seconds before reinflating the cuff' was alse 0%, 'rapidly deflating the cuff', 0.3%, 'rapidly and steadily inflating the cuff to the maximal level as per above-mentioned initial systolic pressure assessment step', 0.7%, 'reading the pressure to the nearest 2mmHg mark on the manometer', 10.8%, the remaining items were above 70%. Of the four items on blood pressure recording, the accuracy of 'recording the cuff size' had a frequency of 0.3%, 'recording the patient's position such as sitting, standing or lying position', 10.8%, 'recording the arm or leg which was used for measuring the blood pressure', 53.6%, and 'recording systolic/diastolic pressure', 100%. The variables significantly related to the accuracy of the blood pressure measurement were age, career position at hospital, and qualification education for blood pressure measurement(p<0.01). In the multiple regression analysis, position and qualification education were significant variables(p<0.01). In conclusion, the accuracy of blood pressure measurement was very low, thus, qualification education for blood pressure measurement should be done immediately to improve the accuracy of measurement by nurses in general hospitals.

• Journal of Families and Better Life
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• v.4 no.1
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• pp.15-31
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• 1986

The purpose of this study is to investigate the relationship between the level of stress recognition of urban housewife and the method of coping, and to explore bow these factors are influenced by socio-demographic variables such as the age of housewife, level of education, status of employment, number of children, durations of marriage, types of family, religion and socio-economic status. The research was conducted on 431 housewives in Seoul in August, 1985. As for the measurement of the instrument, 48 item questionnaire made by investigator was used. The questionnaire was based upon modified and upplemented Holme & Rahe's SRRS and Bell's 18-item Questionnaire to be appropriate to Korean culture. Data were analyzed by percentage, frequency and mean, and verified significant difference by ANOVA and performed Spearman's correlation coefficient. The results of this study are as follows; 1) There is some similarity in distribution of the level of stress recognition of urban housewife. 2) the level of education and the durations of marriage have influence upon the level of stress recognition of urban housewife. In each area, there are differences among groups : age, level of education, durations of marriage, number of children and types of family in the area of education ; age, status of employment, and durations of marriage in the area of health; level of education, durations of marriage, number of children and socio-economic status in the area of finance; status of employment in the area of household work. 3) There are several methods in the method of coping to stress of housewife and the score of long-term coping method appears higher than that of short-term. 4) The level of education, number of children, religion and socio-economic status were variables to have influence on the method level of education, religion and socio- economic status were variables to have influence and in the long-term coping method level of education, number of children, religion, and socio-economic status were to have influence. 5) There is very low positive correlation between the level of stress recognition of urban housewife and the method of coping to stress( ρ=.10, P<.05). 6)In the relation between several variables in socio-demographic variables and the method to coping to stress, the lower the level of stress recognition there are negative correlation (ρ=-.28, P<.01) between religion and the method of coping and also negative correlation (ρ=-.16, P<.05) between number of children and the method of coping. There are positive correlation between socio-economic status and the method of coping.

• Journal of dental hygiene science
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• v.11 no.4
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• pp.353-359
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• 2011

This study was designed to identify a subjective symptom level by Indoor air according to ventilation system in Dental Clinic. The number of respondents was 582 who work in dental clinic and period of investigation was October 2010 through January 2011. A structured questionnaire was employed to evaluate the level of participants' sociodemographics, job-related factors, work place condition, a subjective symptom. Most of respondents were answered that time for symptom to begin was at around 2 P.M. and time for symptom to feel serve pain was at around 3 P.M. and ventilation frequency per a day was often in case of individual cooling and heating system. More often natural ventilation and in case of individual cooling and heating system, the level of subject symptom was low and multiple regression analysis has found that indoor air quality related elements were main factors that influence to the feeling of satisfaction in work place. The results of this study suggest that more often natural ventilation was very important to reduce the level of subjective symptom. Thus, a management program for indoor air quality is strongly recommended by natural ventilation, maintenance man for promotion of quality of life in dental hygienist and to improve dental service and competitiveness.

• Journal of IKEEE
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• v.13 no.4
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• pp.63-68
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• 2009

The power management integrated circuit(PMIC) for CCD image sensor is presented in this study. A CCD image sensor is very sensitive against temperature. The temperature, that is heat, is generally generated by the PMIC with low efficiency. Since the generated heat influences performance of CCD image sensor, it should be minimized by using a PMIC which has a high efficiency. In order to develop the PMIC with high efficiency, the input stage is designed with synchronous type step down DC-DC converter. The operating range of the converter is from 5V to 15V and the converter is controlled using PWM method. The PWM control circuit consists of a saw-tooth generator, a band-gap reference circuit, an error amplifier and a comparator circuit. The saw-tooth generator is designed with 1.2MHz oscillation frequency. The comparator is designed with the two stages OP Amp. And the error amplifier has 40dB DC gain and $77^{\circ}$ phase margin. The output of the step down converter is connected to input stage of the charge pump. The output of the charge pump is connected to input of the LDO which is the output stage of the PMIC. Finally, the PMIC, based on the PWM control circuit and the charge pump and the LDO, has output voltage of 15V, -7.5V, 3.3V and 5V. The PMIC is designed with a 0.35um process.

• Science of Emotion and Sensibility
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• v.20 no.3
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• pp.13-22
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• 2017

Emotion has a direct influence such as decision-making, perception, etc. and plays an important role in human life. For the convenient and accurate recognition of high-arousal negative emotion, the purpose of this paper is to design an algorithm for analysis using the bio-signal. In this study, after two emotional induction using the 'normal' / 'fear' emotion types of videos, we measured the Galvanic Skin Response (GSR) signal which is the simple of bio-signals. Then, by decomposing Tonic component and Phasic component in the measured GSR and decomposing Skin Conductance Very Slow Response (SCVSR) and Skin Conductance Slow Response (SCSR) in the Phasic component associated with emotional stimulation, extracting the major features of the components for an accurate analysis, we used a discrete wavelet transform with excellent time-frequency localization characteristics, not the method used previously. The extracted features are maximum value of Phasic component, amplitude of Phasic component, zero crossing rate of SCVSR and zero crossing rate of SCSR for distinguishing high-arousal negative emotion. As results, the case of high-arousal negative emotion exhibited higher value than the case of low-arousal normal emotion in all 4 of the features, and the more significant difference between the two emotion was found statistically than the previous analysis method. Accordingly, the results of this study indicate that the GSR may be a useful indicator for a high-arousal negative emotion measurement and contribute to the development of the emotional real-time rating system using the GSR.