• Title/Summary/Keyword: frequency effect

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Hearing Loss in the Workers Exposed to Organic Solvents and Noise (유기용제와 소음에 폭로된 근로자들의 청력 손실)

  • 김영기;이용환
    • Journal of Life Science
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    • v.9 no.2
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    • pp.136-145
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    • 1999
  • The purpose of this study was to evaluate the effect of organic slovents and noise on hearing loss. We selected organic solvents exposed group of 32 cases, noise exposed group of 31 cases, both noise and solvent exposed group of 31 cases, and control group of 53 cases and studied the relation between exposure level of noise and organic solvents and degree of hearing loss. The results were as follows. The subjects under investigation were exposed to noise and organic solvents under threshold limit values and the amount of urinary hippuric acid excretion were also under biological exposure indices. In case of noise, both noise and organic solvents exposed group and noise exposed group were more exposed than organic solvents exposed group(p<0.05). When urinary hippuric acid excretion were concerned, both noise iud organic solvents exposed group and organic solvents exposed group showed higher values than noise exposed group(p<0.05). In comparison of mean auditory threshold values by frequency, on the air conduction test, both noise and organic solvents exposed group showed significantly higher hearing loss than noise exposed group in 500Hz of right ear, 500 and 2000Hz of left ear(p<0.05). Forty-three cases among 147 subjects were regarded as hearing loss group and average age(42.6years) of hearing loss group was higher than normal groups average age of 38.0 years. Urinary hippuric acid excretions of hearing loss group were significantly higher than normal group(p<0.05). Thirty-eight percent(12cases) of noise exposed group, 40.6 $\%$(13cases) of organic solvents exposed group, 51.6 $\%$(16cases) of both noise and organic solvents exposed group, and 3.8 $\%$(2cases) of unexposed group were regarded as hearing losers. Exposed groups showed higher incidence of hearing loss than unexposed group but there were no significant differences among the exposed groups. The variables showing significant correlation with hearing loss were age and the amount of hippuric acid in urinary excretion. When age were adjusted for the purpose of seeing the effects of hearing losses due to organic solvent, urinary excretion of hippuric acids was the only variable with significant correlation with hearing loss (p<0.05). When odds ratio to hearing loss between control and exposed groups was considered, noise exposed group showed 6.1 times (95 $\%$ CI: 3.3-8.7), organic solvents exposed group showed 7.4 times (95 $\%$ CI: 3.5-14.6) and both noise and organic solvents exposed group showed 17.2 times(95% CI: 5.6-31.8) higher values than unexposed group(p<0.01). Above results suggest that health screening test of hearing loss is also needed in organic solvents exposed workers.

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Linkage Disequilibrium and Gene Expression Analyses of IGF2 Gene in Korean Native Pigs (재래돼지를 이용한 IGF2 유전자의 연관불균형과 유전자발현양상에 대한 분석)

  • Li, Song-Lan;Li, Xiaoping;Choi, Bong-Hwan;Lee, Cheol-Koo;Cho, Byung-Wook;Kim, Jong-Joo;Kim, Kwan-Suk
    • Journal of Animal Science and Technology
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    • v.51 no.1
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    • pp.9-14
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    • 2009
  • Insulin-like growth factor 2 (IGF2) is the first identified imprinted gene, which is paternally expressed in multiple mammalian species. A paternally expressed QTL for muscle growth and backfat thickness (BFT) has previously been identified near the IGF2 locus on the distal tip of pig chromosome 2 (SSC2p). Therefore the IGF2 gene is considered an economically important candidate gene for pig industry. Herein, this study explored genetic variation of IGF2 for in3-G3072A, in7-G162C and a new SNP in intron7 (C1589T) in Korean native pig (KNP) and commercial pig breeds, and detected their linkage disequilibrium within these breeds. Furthermore we investigated the effect of in3-G3072A on IGF2 gene expression in post-natal muscle and backfat tissues. The real-time quantitative PCR results showed that animals inherited allele G from a KNP sire had significant higher IGF2 gene expression in backfat tissue than those inherited allele A from a Yorkshire sire, however opposite situation in muscle. These results demonstrated the allele 3072G is associated with a higher IGF2 gene expression in fat tissues, but low gene expression in muscle tissues when compared with the 3072A allele. These results suggest that KNP with lower muscle mass and higher fat deposition might be associated with a higher frequency of the 3072G allele, and selecting KNP based on IGF2 genotypes could result in an economic benefit to KNP producers.

A study on the intake of foods causing dental caries and the effect of nutrition education for primary students (초등학교 아동의 치아우식성 식품섭취 및 영양교육 효과에 관한 연구)

  • 김혜영;원복연;류시현
    • Korean journal of food and cookery science
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    • v.18 no.6
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    • pp.704-715
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    • 2002
  • This study intended to compare dietary and snack habits of primary students in the schools providing and non-providing lunch to clarify the correlation between those conditions and the occurrence of dental caries. Furthermore, this study also focused on evaluating educational effects by providing children with nutritional education program. 1. As a result of dietary habit analysis, it was found that children from the school providing lunch were better in terms of breakfast regularity, eating speed. optimum amount of intake, and meal time regularity than those from the school non-providing lunch. In particular, it was noted that children from the school providing lunch took a little more meat, fish, seaweed and milk or dairy products than those from school non-providing lunch. Thus, it could be assumed hat children provided with lunch have more reasonable dietary habit than those without lunch program. In general, it was found that there was a slight positive change in children's dietary habit after nutritional instruction than before, suggesting that the nutritional education had effects on improving their dietary habit. 2. It was found that primary students often took snacks causing dental caries such as caramel, chocolate, sweets and biscuits, and children from the school providing lunch were more willing to reduce those snacks upon recognizing the causes of dental caries than those from the school non-providing lunch. For the children who chewed gum with physical cleansing effects, it was shown that the highest frequency wat twice or three times a week. Moreover, the ratio of children who took snacks following dinner which might affect their dental caries and the ratio of children who selected snacks because of TV commercial were both reduced after nutritional education. Also the consumption of detergent foods like vegetable, fruit, protein. seaweed. milk or dietary products after nutritional education was increased. 3. It was found that children from the school providing lunch took more often all food groups except for food group IV affecting dental caries than those from the school non-providing lunch. The average number of consuming foods which cause dental caries was 5.04 times per person a day, and most of those were rather taken by liquid than solid food. The average eating times of rinsing foods which kill the bacteria on the surface of teeth and prevent from dental caries, was 9.33 for a person a day, which was a little higher than recommended time. Exposed time for dental caries for a person a day was 100.9 min, of which liquid dental caries was 56.2 min and solid dental caries was 44.6 min, suggesting that liquid food had a high potential to cause dental caries.

The Effect of Adequate Radiation Shield Production for Radiation Worker (방사선 차폐체 제작을 통한 작업종사자 피폭 감소 방안)

  • Kim, Ki;Hong, Gun-Chul;Kwak, In-Suk;Park, Sun-Myung;Choi, Choon-Ki;Seok, Jae-Dong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.2
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    • pp.41-44
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    • 2010
  • Purpose: Along with recent advances in PET/CT instrumentation and imaging technology, the number of patients has also been steadily increasing. This resulted in the increased radiation exposure to radiation workers in PET/CT rooms. In this study, we installed a radiation shield and investigated whether it could reduce radiation exposure to the workers and thus enhance job satisfaction. Materials and Methods: A radiation shield is composed of 5 cm thick lead and has a structure in which a radiation worker sits and watches a patient through lead glass while injecting radiopharmaceutical to the patient. Quarterly absorbed dose of radiation workers was measured using thermoluminescence dosimeters (TLD) and the results were compared for six months each before and after installation of the radiation shield. Exposure dose was also measured using a pocket dosimeter placed at the same location in the front and the back of the radiation shield. In addition, frequency of use of the shield and job satisfaction of radiation workers were investigated using a survey. Results: Quarterly absorbed dose of radiation workers was 2.70 mSv on average before installation of new radiation shield, whereas that dropped to 2.13 mSv after installation of radiation shield, reducing radiation exposure dose by 21%. Exposure dose on the front side of the shield was 61.2 R, whereas that on the back side of shield was 2.8 R. According to the survey, 85% of workers used the shield and were satisfied with the outcome: each radiation worker made injections to patients average of 6.5 times/day and preferred sitting to standing while injecting radiopharmaceutical to patients. Conclusion: Use of radiation shield reduced the exposure dose of radiation workers, which is the ultimate goal of radiation protection to minimize radiation exposure and is an appropriate method for the improvement of hospital working environment. Furthermore, we found that use of radiation shield not only relieves physical and psychological burden of radiation workers but also enhances job satisfaction. This result indicates that use of radiation shield is important for improvement of the radiation workers' job environment in terms of radiation protection.

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A Nationwide Survey on the Child Day Care and Common Infectious Diseases (영유아의 보육시설 이용과 감염성 질환 실태 연구)

  • Ahn, Jong Gyun;Choi, Seong Yeol;Kim, Dong Soo;Kim, Ki Hwan
    • Pediatric Infection and Vaccine
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    • v.19 no.1
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    • pp.19-27
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    • 2012
  • Purpose : As the number of children who attend child care centers has increased, concerns has increased about the effect of child day care on childhood illness. This study was conducted to examine the relationship between experience in child care and common infectious diseases in children under 5 years of age. Methods : Data were collected by surveying 1,000 respondents with children under age 5 through online interviews using a structured questionnaire. The contents of the survey were composed of demographic characteristics, child care facilities usage, experience in infectious diseases, and immunization status Results : Among the 1,000 children <5 years of age, 78.5% attended a child care facility. Rates of common communicable illnesses were higher in children in child care than for children reared exclusively at home. The predominant communicable diseases which the respondents' children experienced, in order of decreasing frequency, were gastroenteritis (47.1%), otitis media (41.8%) and pneumonia (19.1%). The immunization rate of vaccines that are not included the national immunization program (NIP) (Haemophilus influenzae type b vaccine - 76.6%, hepatitis A vaccine - 63.3%, pneumococcal vaccine - 59.4%, rotavirus vaccine - 43.1%) was lower than that of the NIP vaccines (90.4%) Conclusion : Children in child care experience more bouts of common infectious disease, so nationwide policies to prevent or to control the spread of infectious agents in a child-care should be available and appropriate immunization should be emphasized as the most effective method for the control of infectious disease for children.

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Human Impact on Sedimentary Environment of Estuarine Coastal Salt Marches, Southern Coastal Region of Korea Peninsula (인위적 환경변화에 따른 해안지역 퇴적환경의 변화)

  • 박의준
    • Journal of the Korean Geographical Society
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    • v.36 no.2
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    • pp.111-125
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    • 2001
  • An estuary is semi-inclosed inlets, located between terrestrial and marine environment. Since many estuaries along south-western coasts of Korean peninsula were affected by human settlements and activities, significant changes in sedimentation environments have been observed. The research area is divided into three distinct morpho-stratigraphic units: fluvial dominated area(Area1), mixed area(Area 2), tide-dominated area(Area3). The landform of this area has been changed by reclamation and river channel change. Temporal variations affected by dam construction, periodic freshet was iterrupted. Sediments began to continuously accmulate on estuary banks by tide. Meanwhile, because of the continuous but reduced discharge of fresh water, the salinity of estuarine sediments was declined. That processes made vegetated area( Phregmites lonivalvis and Suaeda japonica) to be expanded. It indicates that the magnitude and frequency of geomorphic processes has been significantly changed.

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Earthquake Monitoring : Future Strategy (지진관측 : 미래 발전 전략)

  • Chi, Heon-Cheol;Park, Jung-Ho;Kim, Geun-Young;Shin, Jin-Soo;Shin, In-Cheul;Lim, In-Seub;Jeong, Byung-Sun;Sheen, Dong-Hoon
    • Geophysics and Geophysical Exploration
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    • v.13 no.3
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    • pp.268-276
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    • 2010
  • Earthquake Hazard Mitigation Law was activated into force on March 2009. By the law, the obligation to monitor the effect of earthquake on the facilities was extended to many organizations such as gas company and local governments. Based on the estimation of National Emergency Management Agency (NEMA), the number of free-surface acceleration stations would be expanded to more than 400. The advent of internet protocol and the more simplified operation have allowed the quick and easy installation of seismic stations. In addition, the dynamic range of seismic instruments has been continuously improved enough to evaluate damage intensity and to alert alarm directly for earthquake hazard mitigation. For direct visualization of damage intensity and area, Real Time Intensity COlor Mapping (RTICOM) is explained in detail. RTICOM would be used to retrieve the essential information for damage evaluation, Peak Ground Acceleration (PGA). Destructive earthquake damage is usually due to surface waves which just follow S wave. The peak amplitude of surface wave would be pre-estimated from the amplitude and frequency content of first arrival P wave. Earthquake Early Warning (EEW) system is conventionally defined to estimate local magnitude from P wave. The status of EEW is reviewed and the application of EEW to Odesan earthquake is exampled with ShakeMap in order to make clear its appearance. In the sense of rapidity, the earthquake announcement of Korea Meteorological Agency (KMA) might be dramatically improved by the adaption of EEW. In order to realize hazard mitigation, EEW should be applied to the local crucial facilities such as nuclear power plants and fragile semi-conduct plant. The distributed EEW is introduced with the application example of Uljin earthquake. Not only Nation-wide but also locally distributed EEW applications, all relevant information is needed to be shared in real time. The plan of extension of Korea Integrated Seismic System (KISS) is briefly explained in order to future cooperation of data sharing and utilization.

The Needs for Rehabilitation Day Care Center in Stroke Patients (뇌졸중 환자의 주간 재활간호센터에 대한 요구)

  • Ko, Sun-Hwa;Lee, Myung-Ha
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.9 no.2
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    • pp.114-128
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    • 2002
  • In order to provide information for the establishment and maintenance of a rehabilitation day care center for stroke patients. this study is to assess needs for the rehabilitation day care center of the stroke patients and to identify the factors influencing the needs for the center. The data were collected face-to-face interview with 223 stroke patients. using a structured questionnaire. from September 24. 2001 to November 20. 2001. Major findings are as follows. 1. Most of the participants($94.6\%$) needed rehabilitation day care center for stroke patients. $95.5\%$ of participants were willing to use the rehabilitation day care center. 2. Also the score of the needs for the center's health services was $2.84\pm60$ out of 4.00. In regards to the sub-contents. while the physical exercise therapy showed the highest mark($3.54\pm71$) in the needs. the following marks showed physical therapy($3.48\pm79$), training for the memory. thinking and judgment($3.30\pm93$). training for ADL($3.09\pm99$). health education program($3.04\pm93$). In the meantime. the expected effects from the use of the center are $2.89\pm61$ out of 4 and its sub-contents showed that the center would promote their physical and mental well-being($3.30\pm74$) and the center would be more effective than in home care($3.12\pm70$). 3. Meanwhile. the desired frequency of use in the future and distance had significant interrelation with their families living together(p<.05). In addition those who paid to use it differentiated significantly according to their ages and the types of insurance they had(p<.05). 4. The needs in degrees of speech disorder therapy and hobbies & amusements. the patients with other disease had significantly higher degrees than those patients without it (p<.05). Also in regard to the need degrees for physical therapy. healthy education programs and individual counseling including their families. the degrees of the patients with speech disorders were significantly lower than those of the patients without the disorder (p<.05). On the other hand. the patients with speech disorders were significantly higher than those patients without it in the need degree of the speech disorder therapy (p=.000). And the needs in degree concerning about speech disorder therapy. physical exercise therapy. training for ADL. medicinal substances therapy and family education were negatively correlated with the ADL (r=-.236$\sim$.305, (p<.005). 5. Finally. the expected effect of using the rehabilitation day care center showed significant differences statistically according to whether or not they had other disease (p<.05). In conclusion. the study showed the stroke patients were willing to use the center and had a high requirements for it and they especially had relatively high need degrees for the physical exercise therapy. physical therapy. training for memory. thinking and judgment. and healthy education program. And significant factors for the use of the center were their ages. types of insurance. family cohabitation. complications and speech disorders. ADL and so forth. Accordingly. the rehabilitation day care center needs to be established for the stroke patients and the center should develop rehabilitation care programs. which are individual and special programs customized for each patient's characteristics and health conditions.

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Comparison of Mitral Valve Repair between a Minimally Invasive Approach and a Conventional Sternotomy Approach (승모판 성형술에 있어 최초 침습적 수술방식과 고전적 정중 흉골 절개술을 통한 접근방식의 비교)

  • Cho, Won-Chul;Je, Hyoung-Gon;Kim, Jeong-Won;Lee, Jae-Won
    • Journal of Chest Surgery
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    • v.40 no.12
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    • pp.825-830
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    • 2007
  • Background: Minimally invasive cardiac surgery appears to offer certain advantages such as earlier postoperative recovery and a greater cosmetic effect than that achieved through conventional sternotomy. However, this approach has not yet been widely adopted in Korea to replace complex open heart surgery such as mitral valve reconstruction. This study compared the results of robot assisted minimally invasive mitral valve repair with those results of conventional sternotomy. Material and Method: From December 1993 to December 2005, 520 consecutive patients underwent mitral valve reconstruction for mitral regurgitation in our institution. These patients were subdivided according to those whose surgery used the conventional sternotomy approach (Group S, n=432) and those who underwent minimally invasive right anterior thoracotomy (Group M, n=88); we then compared the clinical results of both groups. When we performed minimally invasive right thoracotomy, we used a robot (AESOP 3000) and made an incision less than 5 cm. Result: Our study patients in both groups were similar for their age, gender and preoperative ejection fraction. There were two hospital mortalities in group S. but there was no mortality in the group M patients. Significant reductions in the ICU stay and the postoperative hospital stay were observed in the group M patients compared with the group S patients. However, both the bypass time and the aortic cross-clamp time were significantly longer in the group M patients. In spite of the confined incision in the group M patients, there were no limitations on the mitral valve repair techniques. There was a similar frequency of postoperative significant residual mitral regurgitation in both groups. Conclusion: In this study, the minimally invasive mitral valve repair showed comparable early results with the conventional sternotomy patients. We will now need long-term follow-up of these patients who underwent minimally invasive mitral valve repair, but we anticipate that based on the results of this study, we will begin to routinely perform minimally invasive cardiac surgery as out primary approach for mitral valve reconstruction.

A Study on the Occurrence of Benzo(a)pyrene in Fats and oils by Heat Treatment(I) (유지가열시 Benzo(a)pyrene 생성에 관한 연구(I) -대두유가열시-)

  • 김인숙;안명수;장대경
    • Korean journal of food and cookery science
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    • v.9 no.4
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    • pp.323-328
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    • 1993
  • Benzo(a)pyrene [B(a)P], one of the polycyclic aromatic hydrocarbons (PAHs) is known as a potent carcinogen. As lipid consumption increases recently, the toxic effect of overheated lipid foods and fats & oils were reported increasingly. In this study, the contents of B(a)p, other PAHs and rancidities of soybean oil were determined, and then the proper heating temperature, time and frequency were recommended, The work was carried out using soybean oil heated at $180\pm$5^{\circ}C$$, $200\pm$5^{\circ}C$$, and $300\pm$5^{\circ}C$$,for 50 hours. Acid Value(AV) and Conjugated Diene Value of samples were determined. The contents of B(a)P and other PAHs contents of all samples were masured by HPLC/UV method. The results obtained were as follows; Each content of PAHs in the fresh soybean oil was: Pyr 1.093, B(a)A 0.986, Ch 1.147, DMBA 1.082, B(e)P 0.664, Per 1.135, B(a)P 0.146, DBA 1.053, 3-MC 0.05 rg/kg. When the soybean oil was heated at $180\pm$5^{\circ}C$$, for 10, 20, 30, and 50 hours, B(a)P conterlts in heated soybean oils were 0.391, 0.692, 0.451, and 0.372 $\mu\textrm{g}$/kg respectively. Acid value of them were 0.26, 0.26, 0.29, and 0.33, and conjugated diene value was 0.67, 0.76, 0.99, and 1.04, respectively. When the soybean oil was heated at $200\pm$5^{\circ}C$$,and $300\pm$5^{\circ}C$$,for 10, 20, 30, and 50 hours, B(a)P coiltents in soybean oil heated at $200\pm$5^{\circ}C$$,were 0.844, 0.512, 0.479 and 0.247 Ig/kg respectively, Acid value 0.22, 0.21, 0.23 and 0.51 and CDNV 0.39, 0.49, 3.27, and 3.89. B(a)P contents in soybean oil heated at $300\pm$5^{\circ}C$$,were 0.466, 0.706, 0.607 and 0.247$\mu\textrm{g}$/kg respectively, Acid value 0.47, 1.57, 3.90, and 6.42 and CDNV 0.65, 2.15, 3.00, and 3.88.

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