• Progress in Medical Physics
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• v.14 no.3
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• pp.203-210
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• 2003

PET (positron emission tomography) permits the investigation of physiological and biochemical processes in vivo. The accuracy of quantifying PET data is affected by its finite spatial resolution, which causes partial volume effects. In this study, we developed a method for partial volume correction using Hoffman phantom PET and MR data, and applied various FWHM (full width at half maximum) levels. We also applied this method to PET images of normal controls and tested for the possibility of clinical application. $^{18}$ F-PET Hoffman phantom images were co-registered to MR slices. The gray matter and white matter regions were then segmented into binary images. Each binary image was convolved by 4, 8, 12, 16 mm FWHM levels. These convolved images of gray and white matter were merged corresponding to the same level of FWHM. The original PET images were then divided by the convolved binary images voxel-by-voxel. These corrected PET images were multiplied by binary images. The corrected PET images were evaluated by analyzing regions of interests, which were drawn on the gray and white matter regions of the original MR image slices. We calculated the ratio of white to gray matter. We also applied this method to the PET images of normal controls. On analyzing the corrected PET images of Hoffman phantom, the ratios of the corrected images increased more than that of the uncorrected images. With the normal controls, the ratio of the corrected images increased more than that of the uncorrected images. The ratio increase of the corrected PET images was lower than that of the corrected phantom PET images. In conclusion, the method developed for partial volume correction in PET data may be clinically applied, although further study may be required for optimal correction.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.103-107
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• 1997

Purpose: To investigate the localization and functional lateralization of the supplementary motor area (SMA) in motor activation tests in comparison to that of the primary motor area. Materials and Methods: Seven healthy volunteers obtained echoplanar imaging blood oxygen level dependent technique. This study was carried on 1.5T Siemens Magnetom Vision system with the standard head coil. Parameters of EPI were followed as; TR/TE : 1.0/66.0msec, flip angle: $90^{\circ}$, field of view: $22cm{\times}22cm,{\;}matrix:{\;}128{\times}128$, slice number/slice thickness/gap: 1O/4mm/0.8mm with fat suppression technique. Motor task as finger opposition in each hand consisted of 3 sets of alternative rest and activation periods. Postprocessing were done on Stimulate 5.0 by using cross-correlation statistics. To compare the functional lateralization of the SMA in the right and left hand tests, each examination was evaluated for the percent change of signal intensity and the number of activated voxels both in the SMA and in the pri¬mary motor area. Hemispheric asymmetry was defined as difference of summation of the activted voxels between each hemisphere. Results: Percent change of signal intensity in the SMA (2.49 -3.06%) is lower than that of primary motor area(4.4 -7.23%). Percent change of signal intensity including activated voxels were observed almost equally in the right and left SMA. As for summation of activated voxels, primary motor area had significant difference between each hemisphere but not did the SMA. Conclusion: Preferred contralateral dominant hemisphere and hemispheric asymmetry were detected in the primary motor area but not in the SMA.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.579-596
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• 1996

The first purpose of this study was to compare the mean Knowledge, Attitude & Practice(KAP) scores concerning major occupational health between two types of occupational health management in small & medium-scale textile factories. Sample number was 1,138 workers. In small & medium factories with 300 workers or less, they have two alternatives for occupational health management ; Individual Health Management or Vicarious Health Management. The second purpose was to determine if there was a relationship between duration of Vicarious health management and mean KAP scores for 694 workers from the Vicarious Health Management group. We used self-administered questionnaires for measuring KAP. The results of this study were; 1. There was significant difference concerning all socioeconomic & occupational variables (gender, age, education level, marital status, Blue/White collar, working duration of present factory, working duration of total factories) except for shift. 2. There was no significant difference of mean scores of Knowledge and Attitude between the Individual Health Management Group and the Vicarious Health Management. But, the mean score of Practice was significantly different. 3. According to multiple regression analysis, the mean score of Knowledge significantly increased with age, education level, working duration of all factories increased. The mean score of Attitude significantly increased with age, education level and married. The mean score of Practice significantly increased with age, education level, working duration of all factories, married and men. 4. In conclusion, The type of Health management did not significantly affect the mean KAP scores concerning major occupational Health problems. 5. But, the Duration of Vicarious Health management significantly increased the mean KAP scores.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.334-346
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• 1995

To investigate the factors influencing workers' perception and attitude toward special periodic health screening test for workers, a survey with self-administered questionnaires was performed on 779 workers who had special periodic health screening test from September 1 to October 15, 1994. A study model was developed by modifying the health belief model. The end and intermediate response variables of the model were the voluntary participation and necessity perception on the special screening for workers. The result of analysis was consistent with the study model. Rates for the necessity perception and voluntary participation on the special screening for workers were 77.2%, 79.2%, respectively. Factors influencing on the voluntary participation were necessity perception, benefit of special screening for workers, and cue to action. And on the necessity perception were susceptibility and severity to occupational disease, knowledge to special screening for workers, and support of company. General and occupational characteristics influencing on the susceptibility and severity to occupational disease were sex, age, educational level, work duration, and health education. On the knowledge to special screening for workers were age, educational level, work duration, and locus-of-control. On the benefit of special screening for workers were age, locus-of-control, pride on health, and health education. Therefore, to increase the voluntary participation and necessity perception on the special periodic health screening for workers, 1) if a worker is judged as occupational disease, the judgment should be widely known in his workplace, 2) the screening result forms should be directly sent to the workers themselves, 3) for the positivity of employers, the campaign and education program subjected to them should be planned, 4) health education should give the first consideration to the younger, lower educational level, and newly employed women, and its frequency should be increased and it should be more frequently dealt with occupation-related subjects, and 5) the employers should have a careful concern in not being disadvantageous to workers due to result of screening.

• Journal of the Korean Society of Radiology
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• v.9 no.1
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• pp.47-53
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• 2015

Quantitative analysis of MR spectrum depending on mole concentration of the contrast media in cereberal metabolite phantom was performed. PRESS pulse sequence was used to obtain MR spectrum at 3.0T MRI system (Archieva, Philips Healthcare, Best, Netherland), and the phantom contains brain metabolites such as N-Acetyl Asparatate (NAA), Choline (Cho), Creatine (Cr) and Lactate (Lac). In this study, optimization of MRS PRESS pulse sequency depending on the concentration of contrast media (0, 0.1 and $0.3mmol/{\ell}$) was evaluated for various repetition time(TR; 1500, 1700 and 2000 ms). In control (cotrast-media-free) group, NAA and Cho signals were the highest at TR 2000 ms than at 1700 and 1500 ms. Cr had the highest peak signal at TR 1500 ms. When concentration of contrast media was $0.1mmol/{\ell}$, the metabolites were increased NAA 73%, Cho 249%, Cr 37% at TR 1700 ms compared with other TR, and also signal increased at $0.3mmol/{\ell}$, In $0.5mmol/{\ell}$ of contrast agent, cerebral metabolite peaks reduced, especially when TR 1500 ms and 2000 ms they decreased below those of control group. The ratio of metabolite peaks such as NAA/Cr and Cho/Cr decreased as the concentration of the contrast agent increased from 0.1 to $0.5mmol/{\ell}$. Authors found that the optimization of PRESS sequence for 0.3T MRS was as follows: low density of contrast agent ($0.1mmol/{\ell}$ and $0.3mmol/{\ell}$) made the highest signal intensity, while high density of contrast agent reveals the least reduction of signal intensity at 1700 ms. In conclusion, authors believe that it is helpful to reduce TR for acquiring maximum signal intensity.

• Journal of the Korean Society of Radiology
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• v.12 no.4
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• pp.481-489
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• 2018

In MRI examination, when irradiating the human body with RF Pulse to acquire images, the portion of the irradiated RF Pulse energy is absorded into the human body, and this will affect the temperature of the human body. If a metal is inserted into the human body even if the same RF Pulse energy is applied, the SAR value increases and the body temperature changes due to the increase in the electromagnetic wave conductivity of the metal. So we measure and compared with the change in the SAR and temperature in the implant material of the dental implant in Brain MRI examinations. Experiments were performed on a human head model using a 64MHz and 128 MHz RF Pulse frequency generated by a 3.0 Tesla MRI apparatus. And then changed material of dental implants to Titanium and $Al_2O_3$. Using the XFDTD program, the changes in SAR and body temperature around the head were examined. When with Titanium the SAR value and temperature of Brain increased, but with $Al_2O_3$ showed lower SAR and temperature as compared with Titanium. The dental implants were low in SAR and temperature of the head in $Al_2O_3$, which are electrical insulators with low electrical conductivity, compared to Titanium, which is an electrical conductor. It is necessary to study the biologic effect of patient with brain MRI when titanium dental implant material is inserted in the future. Because the maximum value of SAR is much higher than the limit when dental implant material is Titanium. In addition, it is necessary to use an implant of $Al_2O_3$ material to reduce the SAR value and temperature of the Brain in Brain MRI examination.

• Development and Reproduction
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• v.14 no.4
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• pp.243-251
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• 2010

ESRRB (Estrogen related receptor $\beta$) is an orphan receptor, and have a role on maintaining the undifferentiated state and self-renewal of pluripotent stem cell as a transcription factor which regulates the expression of OCT4 and NANOG genes. Also, Feng et al. (2009) reported that Esrrb, Oct4 and Sox2 could induce pluripotent stem cell from somatic cells. The aim of the present study was to develop the direct delivery system of human ESRRB protein into human amniotic fluid-derived stem cells (AFSCs) and to analyze the effect of ESRRB on the regulation of pluripotency-related genes. Human ESRRB has three isoforms arisen by alternative splicing. We cloned short-form ESRRB and made a fusion protein of ESRRB and R7 for an efficient protein transfer to cell. R7 as cell-penetrating peptide(CPP) can help to transfer ESRRB into cells. R7-ESRRB-His6 protein was observed in the cytoplasm and nuclei within 5 hours after treatment. Also, we could observe R7-ESRRB-His6 protein only in the nuclei within 24 hours. Realtime PCR showed that ESRRB increased expression of OCT4 and NANOG as well as SOX2 gene. Therefore, we demonstrated that R7-ESRRB-His6 proteins were efficiently transferred into the nuclei of AFSCs and work well as a possible transcription factor.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.755-762
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• 2000

Physicochemical properties of commercial sweet potato starches manufactured by 7 different companies were investigated in comparison with corn and potato starches. Crude ash and protein content varied from 0.36 to 1.02%, and from 0.04 to 0.14% based on dry weight, respectively. The protein contents were relatively smaller than that of corn or potato starch. But whiteness of the sweet potato starches was less than that of corn or potato starch. Mean diameter of the sweet potato starch granules varied from 14.23 to $21.08\;{\mu}m$ depending on the company and all sweet potato starches showed bimodal size distributions. Pasting viscosity measured by Rapid Viscoanalyzer(RVA) also showed variations among the starches of different companies. The starch from D company in Korea had the lowest pasting temperature$(74.00^{\circ}C)$ whereas the starch from a phillippine company(P) did the highest one$(80.35^{\circ}C)$. The peak viscosity of sweet potato starches was higher than that of corn starch but lower than that of potato starch. The D company starch also showed the highest peak viscosity(2283 cp) among the starches tested. Paste breakdown by hot shearing ranged from 524 cp (S company) to 1279 cp (HL company). Textural properties of the starch gels appeared significantly different among the starches of different manufacturers. The greatest hardness of the gel was $137.90\;g_{f}$ at 1 day storage whereas the lowest value was $31.53\;g_{f}$. Except the starches from 2 companies (P and S), the sweet potato starches formed very soft and weak gels. P or S company starches formed the gels similar to potato starch. Syneresis by freeze-thawing treatments appeared less for sweet potato starch gels than that for corn starch gels, but greater than that for potato starch gel. The overall properties of the sweet potato starches varied by the manufacturing companies, and ranged between those of corn and potato starches.

• Journal of Hospice and Palliative Care
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• v.12 no.1
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• pp.27-31
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• 2009

Purpose: Lymphedemas are tissue fluid swellings, usually on the arms or legs, and occur as a result of impaired lymphatic drainage. Presently, the most effective treatment available is complete decongestive physiotherapy (CDP). However, this therapy is ineffective in some patients and surgery may be indicated. Herein, we examined the efficacy of minimally invasive needle aspiration of the most enlarged areas in hypodermic adipose tissues, of patients who had failed CDP. Methods: We included 21 patients who were diagnosed with lymphedema stage II-III in the upper or lower extremities and visited the lymphedema clinic at a university hospital from September 1, 2003 to February 28, 2004. All patients had been treated with CDP at least once, but had failed to respond to the therapy for more than one year. Nine patients had breast cancer and 12 had cervical cancer. We identified the area with the most severe edema by using MRI and performed a 16-gauge angio-needle aspiration on the area. The patients were followed up for 3 months. Effectiveness of the treatment was evaluated by comparing the volume of edema before and after the treatment using Wilcoxon signed rank-test. Results: The mean reduction ratio of the volume of edema comparison normal volume was 41.1${\pm}$35.3% (P=0.001). There were no major or minor operative complications except localized hemorrhage. Conclusion: We conclude that a needle aspiration prior to other surgical treatments is relatively safe and effective for those patients who are unresponsive to CDP.

• Journal of Nutrition and Health
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• v.46 no.1
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• pp.86-97
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• 2013

This study investigated the eating habits of elementary school children and their perceptions related to traditional Korean foods, based on the health belief model. The subjects were fifth grade elementary school children (274 boys and 274 girls) in eight Korean cities. The results were as follows: The children ate almost three meals per day and were grateful for their meals. However, they irregularly consumed meals and snacks. They tended to eat heartily and did not eat foods that they had not yet eaten. Their meals were based on rice and they have eaten kimchi and vegetables at almost every meal. However, they had undesirable habits in eating other foods, such as fruits, fish, soybeans, and sweet foods. They did not sensitively or seriously perceive their eating habits in relation to their health. They perceived that it was very good for their nutrition, health, and tastes to eat traditional Korean foods, and they had pride in traditional Korean foods and eating style. Although they expressed some difficulty regarding availability and preparation of traditional Korean foods, they hardly felt difficulty in eating them. They had high dietary self-efficacy with regard to eating these foods, except for two items of self-regulation. Their eating habits showed positive correlation with dietary self-efficacy, perceived susceptibility, and perceived benefit. In conclusion, eating habits of elementary school children in relation to traditional Korean foods are not desirable, but not serious. They did not sensitively or seriously perceive their eating habits in relation to their health. However, they perceived that it was very good for their nutrition and health to eat traditional Korean foods, did not have a high level of difficulty in eating them, and had high dietary self-efficacy with regard to eating them. Therefore, we suggest that children should be exposed to various traditional Korean foods, along with education about them, in order to enhance their concern and motivation to eat them.