Seo, Jin Hee;You, Sun Kyoung;Lee, In Ho;Lee, Jeong Eun;Lee, So Mi;Cho, Hyun-Hae
Investigative Magnetic Resonance Imaging
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v.19
no.3
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pp.162-167
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2015
Purpose: To evaluate the usefulness of quantitative analysis of the facial nerve using contrast-enhanced three-dimensional (CE 3D) fluid-attenuated inversion recovery-volume isotopic turbo spin echo acquisition (FLAIR-VISTA) for the diagnosis of Bell's palsy in pediatric patients. Materials and Methods: Twelve patients (24 nerves) with unilateral acute facial nerve palsy underwent MRI from March 2014 through March 2015. The unaffected sides were included as a control group. First, for quantitative analysis, the signal intensity (SI) and relative SI (RSI) for canalicular, labyrinthine, geniculate ganglion, tympanic, and mastoid segments of the facial nerve on CE 3D FLAIR images were measured using regions of interest (ROI). Second, CE 3D FLAIR and CE T1-SE images were analyzed to compare their diagnostic performance by visual assessment (VA). The sensitivity, specificity, and accuracy of RSI measurement and VA were compared. Results: The absolute SI of canalicular and mastoid segments and the sum of the five mean SI (total SI) were higher in the palsy group than in the control group, but with no significant differences. The RSI of the canalicular segment and the total SI were significantly correlated with the symptomatic side (P = 0.028 and 0.015). In 11/12 (91.6%) patients, the RSI of total SI resulted in accurate detection of the affected side. The sensitivity, specificity, and accuracy for detecting Bell's palsy were higher with RSI measurement than with VA of CE 3D FLAIR images, while those with VA of CE T1-SE images were higher than those with VA of CE 3D FLAIR images. Conclusion: Quantitative analysis of the facial nerve using CE 3D FLAIR imaging can be useful for increasing the diagnostic performance in children with Bell's palsy when difficult to diagnose using VA alone. With regard to VA, the diagnostic performance of CE T1-SE imaging is superior to that of CE 3D FLAIR imaging in children. Further studies including larger populations are necessary.
Objectives : As the disabled have higher prevalence rates and earlier onsets of chronic diseases than the non-disabled, their participation in mass screening is important for the early detection and intervention of chronic diseases. Nevertheless, in Korea, the disabled have lower participation rates in mass screening services than the non-disabled. The purpose of the study was to find determinants for the participation in the National Health Insurance (NHI) mass screening program among the disabled. Methods : In this study, the NHI mass screening data of 423,076 disabled people, which were identified using the National Disability Registry (2003), were analyzed. Of the factors affecting the participation rates in mass screenings, the following variables were included for the analysis: socioeconomic stati, such as sex, age, category of health insurance program, region and income, disability characteristics, such as disability type, and severity. A multiple logistic regression analysis was used to evaluate the association between the participation rates, disability characteristics variables and demographic variables. Results : The participation rate in mass screening of the disabled was 41.3%, but was lower in females, an age of more than 70 years, self-employed and for those with an average monthly insurance premium over 133,500 Won and in metropolitan legions. The participation rate was 1.31 times lower in females than males (95% CI=1.29-1.33); 3.50 times lower in the elderly (more than 70 years) than the younger (95% CI=3.33-3.67); 1.43 times lower in those who live in metropolitan areas (95% CI=1.40-1.46); 2.59 times lower for those in a health Insurance program for the self-employed than for employees (95% CI=2.56-2.63), 1.19 times lower for the higher income (more than 133,500) than the lower income group (4,400-22,000) for the average monthly insurance premium (95% CI=1.15-1.23): 2.04 times lower for those with brain palsy and stroke disabilities than with auditory impairments (95% CI: 1.97-2.11) and 3.27 times for those with severe compared to mild disabilities (95% CI=3.15-3.40). Conclusions : The disabled with high severity, and locomotive and communication disabilities have lower participation rates in mass screening services in Korea.
Purpose : To evaluate usefulness of MR imaging after serial brain US in the high-risk neonates before discharge of the neonatal intensive care unit. Materials and Methods : Retrospective comparison of 412 US and 121 MR scans in 121 neonates and young infants were performed. Grading of germinal matrix/intraventricular hemorrhage (GMH/IVH) was performed and presence of intracranial hemorrhage other than GMH/IVH and parencyma lesions was also analyzed. Results : Among the 242 lateral ventricles, Seven GMH and 46 IVH were additionally detected by MRI. On the other hand, 30 GMH were only detected by US. US demonstrated Grade 1/2/3/4 GMH/IVH in 24/8/13/0 ventricles each, while each grades were identified in 3, 49, 10, 2 ventricles on MR images. Other intracranial lesions additionally detected on MR images were cerebral hemorrhage (n=4), cerebellar hemorrhage (n=4), extraaxial hemorrhage (n=8), diffuse excessive signal change of the white matter (n=72), non-cavitary lesion (n=4), encephalomalacia (n=2), and ventriculomegaly (n=5). Conclusion : MR imaging could be an excellent complimentary study after serial brain US for additional detection of the intracranial pathology, particularly IVH and white matter lesions, though US would be better in follow-up of GMH in some neonates.
Kim, Il-Sik;Han, Byeong-Hee;Park, Choon-Su;Yoon, Dong-Jin
Journal of the Korean Society for Nondestructive Testing
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v.35
no.5
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pp.332-340
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2015
Acoustic emission (AE) is an effective nondestructive test that uses transient elastic wave generated by the rapid release of energy within a material to detect any further growth or expansion of existing defects. Over the past decades, because of environmental issues, the use of compressed natural gas (CNG) as an alternative fuel for vehicles is increasing because of environmental issues. For this reason, the importance and necessity of detecting defects on a CNG fuel tank has also come to the fore. The conventional AE method used for source location is highly affected by the wave speed on the structure, and this creates problems in inspecting a composite CNG fuel tank. Because the speed and dispersion characteristics of the wave are different according to direction of structure and laminated layers. In this study, both the conventional AE method and the energy based contour map method were used for source location. This new method based on pre-acquired D/B was used for overcoming the limitation of damage localization in a composite CNG fuel tank specimen which consists of a steel liner cylinder overwrapped by GFRP. From the experimental results, it is observed that the damage localization is determined with a small error at all tested points by using the energy based contour map method, while there were a number of mis-locations or large errors at many tested points by using the conventional AE method. Therefore, the energy based contour map method used in this work is more suitable technology for inspecting composite structures.
To cope with the potential risks associated with invasive alien species, the Korean Government implemented the Biodiversity Act in 2014. Among the alien species not yet introduced into that country, 24 have been designated as alert species. These include mammals, birds, fish, mollusks, insects, and plants that may invade and cause serious harm to the ecosystem. Approval from the Ministry of Environment is required to import or carry any of them. Although these measures are more advanced than those from the previous legal framework, several terms still need to be improved. First, the category of alert species should cover not only those not yet introduced but also those that are being raised or cultivated at aquariums, botanical gardens, and zoos. Second, for applicants who intend to import or carry alert species, the government must provide them with detailed standards for the ecological risk assessment of alert species as well as guidelines for their safe use in Korea to prevent their unregulated release from confinement facilities into natural environments. Third, tools and protocols should be developed for early detection and rapid responses to those escapes.
A total number of 668 apparently healthy fish were obtained from farm to study the effect of two heavy metals (Copper and Mercury) on histopathology of liver, kidney, spleen, gills and muscles also residues in muscles. The $LC_{50}$/96 hr. of Cu and Hg were estimated and fish exposed to 1/2 $LC_{50}$ for 7 days and for 1/10 $LC_{50}$ for 8 weeks from each product separately. Histopathological findings in acute and chronic mercuric chloride toxicity revealed degeneration and necrosis in the glomeruli, interstitium tissue and epithelium lining renal tubules. The tubular epithelium became necrotic at several places. Eosinophilic hyaline droplets is exist in the cytoplasm of the necrosed cells. Degenerative changes and hyperactivity in melanomachrophage center was seen in the spleen together with some necrotic areas. Necrosis and aggregation of melanomachrophage were seen in the hepatic cells, Hepatic cells showed vacuolar degeneration in the hepatic cells. Gills showed loss in the lamellae of the filaments associated with edema, inflammatory cells infiltration and haemorrhages in the arch. The sarcoplasm of the bundles of the skeletal muscle showed granular degeneration and focal inflammatory cells infiltration between the hyalinized bundles. Mercury residues obtained from these studies in the acute toxicity were 0.22 ppm/gm in the 2nd day, 0.411 ppm/gm in the $5^{th}$ day ended with 0.96 ppm/gm in the $7^{th}$ day. In chronic toxicity it was 1.1320, 1.7140, 2.3620 and 3.5640 ppm/gm respectively from the $2^{nd}$ to the $8^{th}$ week of exposure. In acute and chronic copper toxicity, there was degenerative changes in renal tubules. Melanophores aggregation in the wall of the blood vessels of the spleen and depletion of some of the melanophores in the melanomachrophage were seen together with necrosis in some areas. Congested Mvs (Micro vessels) and vacuolation of hepatocytes were observed. Some areas of hemorrhage and melanophores vacuolar degeneration in the liver were seen. There was mitosis in some areas with displesia of hepatopancreatic cells and eosinophilic granular cells aggregation. Zymogen granules disappeared and there were dyplastic hepatocytes. Congestion in the blood vessels of the gill filaments, associated with massive number of granular eosinophilic cells infiltration were seen in the base of the filaments. There were sever vacuolization and hyalinization in the skeletal muscle bundles. Detection of residues of copper sulfate revealed increase of the amount of copper measured in ppm/gm comparing to the normal control starting from 0.60 ppm/g in the $2^{nd}$ day, 0.67 ppm/g in the $5^{th}$ day and 0.67 ppm/g in the $7^{th}$ day. Result obtained in chronic copper sulfate toxicity revealed gradual increase of the amount of copper which ranged from 0.18 ppm/g at the $2^{nd}$ week to 0.21 ppm/g in the $8^{th}$ week of exposure.
Journal of the Institute of Electronics and Information Engineers
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v.50
no.12
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pp.247-253
/
2013
The purpose is a comparative evaluation in the DR System according to the dosimetry and image quality of the quantitative and objective via Direct digital radiography, Indirect digital radiography, Image intensifier (Charge Coupled Device type) digital radiography. The experimental method used rando phantom and measured the entrance surface dose. And through using the measured entrance surface dose and then using the PCXMC program were evaluated risk due to irradiation and the effective dose. SNR and NPS and CNR were measured and analyzed by using 21cm acryl phantom. Significance of measured value was evaluated by statistics method. Entrance surface dose, major organ dose, effective dose all of them were measured the lowest rated in direct DR when it is on the basis of direct DR dose, high-dose ratio were measured in I.I DR approximately 1.3 times, indirect DR approximately 2.4 times. Risk in accordance with radiation also was measured same as dose ratio. On the conclusion that SNR measurement result based on direct DR SNR measurements, low-SNR ratio were measured in I.I DR approximately 7.25 times, indirect DR approximately 1.48 times. On the conclusion that CNR measurement result based on direct DR CNR measurements, high-dose ratio were measured in I.I type DR approximately 1.16 tims and low-dose ratio were measured in indirect DR approximately 0.87 times. Therefore Direct DR system using a-selenium sensing element to detect x-ray photon is thought effectively at the examination such as infant to sensitive irradiation and the genital gland. Because quality image is built by low dose. Also when it is necessary that image test requiring many diagnosis information, indirect DR system is thought effectively.
Purpose: The purposes of this study were in understanding maternal and neonatal risk factors for postpartum depression using Edinburgh Postnatal Depression Scale(EPDS). Methods: Among 788 women, who had delivery include cesarean section in the department of obstetrics and gynecology at OO medical center from May 28th 2008 to October 6st 2009, 72 women filled out EPDS questionnaire sheets. Additional aspects included for the analysis are maternal factors including age, number of children, parity, delivery method, and hemoglobin; and neonatal factors such as weight, sex, gestational age, apgar score, and neonatal intensive care unit admission. Comparison was performed between the women with EPDS score equal or less than 8 and the women with EPDS score equal to or higher than 9 using statistical methods of student t-test for linear variables and chi-square test for non-linear variables. SPSS version 13.0 for windows was used for analysis. Results: Thirty women(41.7%) were included in the postpartum depression risk group (EPDS score ${\geqq}9$). Statistically significant difference(P<0.05) was found in gestational ages of the risk group($36.57{\pm}29.6$ weeks) and the non-risk group ($38.10{\pm}1.97$ weeks). Identified statistically significant risk factors(P<0.05) include cesarean section (OR=3.304 [1.121-9.744]), low birth weight infant(OR =6.500 [1.606-26.314]), preterm delivery(OR=2.857[1.071-7.621]), low apgar score (1minute) after delivery (OR=14.909 [1.750-127.025]). There was no statistically significant difference in maternal age, number of children, parity, hemoglobin, neonatal sex, apgar score (5minutes), NICU admission. Conclusions: Through the results showed, gestational age, delivery method, neonatal weight, apgar score(1minute) were identified as risk factors for postpartum depression. To prevent or minimize postpartum depression, oriental medical intervention is recommended for pregnant women through early detection.
Park, Hyeon-Ju;Lee, Ki-Won;Chung, Kyong-Hwan;Song, Yo-Soon;Seo, Gon
Korean Journal of Environmental Agriculture
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v.26
no.1
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pp.69-76
/
2007
The accumulation curves of phenol in the flesh of apples were measured at $5^{\circ}C$, $25^{\circ}C$ and $40^{\circ}C$ when they were exposed to phenol vapor, The effective diffusivities of phenol at the rind and flesh were determined by comparing its experimentally obtained accumulation curves with simulated ones. The simulation was carried out by the non-steady state diffusion rate equation. The diffusion model assumed the consecutive diffusion of phenol at the rind and flesh of apples. The detection time of phenol in the flesh of apples was shortened with increasing temperature, and it accumulated amount also increased rapidly. The estimated effective diffusivity of phenol at the rind of apples increased with temperature as like $1.1{\times}10^{-13}\;m^2/s$ at $5^{\circ}C$, $1.4{\times}10^{-13}\;m^2/s$ at $25^{\circ}C$ and $2.2{\times}10^{-13}\;m^2/s$ at $40^{\circ}C$, but those at the flesh of apples were invariant as $1.5{\times}10^{-10}\;m^2/s$ at this temperature range. The effect of temperature on the diffusivity of phenol was small, but the increase of the vapor pressure of phenol with temperature accelerated the penetration of phenol at the rind, resulting in the rapid accumulation at the flesh of apple.
Purpose: Patients with chronic gastrointestinal disease are at risk for trace element deficiency due to impaired absorption and gastrointestinal loss. The aim of this study was to evaluate the trace element status of patients with gastrointestinal disease by blood and hair analysis, and to determine the usefulness of hair mineral analysis for diagnosing trace element deficiency not detected by a blood test. Methods: An analysis of hair minerals was performed and compared with blood mineral analysis in 13 patients with chronic gastrointestinal disease. The concentration of each element in the hair and blood was compared in the subgroups based on parenteral nutritional support or clinical symptoms. Results: Almost all patients had trace element deficiency. The trace elements deficient in the blood or hair analysis included zinc, selenium and copper. The hair zinc concentration was significantly lower in the group receiving parenteral nutritional support. The hair selenium concentration was statistically associated with the clinical symptoms of hair loss, brittle hair and loss of hair pigmentation. Conclusion: The results of this study suggest that patients with chronic gastrointestinal disease should receive adequate zinc and selenium replacement to avoid trace element deficiency especially when treated with long-term parenteral nutrition. Hair mineral analysis is useful as a complementary tool for the detection of a trace element deficiency.
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