• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.31-40
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• 1995

We compared stress/rest myocardial Tc-99m-MIBl tomographic image findings with rest/stress rubidium-82 tomographic images. In 23 patients with coronary artery disease (12 of them received bypass grafts before) and 6 normal subjects, rest rubidium PET study was performed : rubidium-82 and Tc-99m-MIBI were injected simultaneously to each patient after dipyridamole stress for rubidium PET and MIBI SPECT; and rest MIBI SPECT was performed 4 hours thereafter. We scored segmental decrease of rubidium or MIBI uptakes into 5 grades for 29 segments from 3 short-axis, vertical and horizontal slices. Scores were summed for each major arterial territory. When more score than two grade-2's or one grade-3 was considered as the cue for significant stenosis for major arterial territories, 67% of 46 stenosed arteries were found with MIBI studies and 78% of them by rubidium studies. Fourteen among 28 grafted arterial territories of 12 post-CABG patients were found normal with both rubidium and MIBI. Segmental scores were concordant between rubidium and MIBI in 72% of 709 stress segments and in 80% of 825 rest segments. Stress rubidium segmental scores were less than stress MIBI scores in 9%, so were rest rubidium scores. Stress rubidium scores were more than stress MIBI scores in 20% of segments, and rest rubidium segmental scores were more than rest MIBl scores in 11%. Rank correlations (Spearman's rho's more than 0.7(stress) and 0.5(rest), slopes (MIBI/rubidium) around 0.7(stress) and 0.9 (rest)) suggested deeper and wider defects in stress with rubidium. Slope over 1 (MIBI/rubidium) with LAD segemental scores at rest and 7 territories which had much larger score with MIBI revealed exaggeration of rest defects with rest MIBI in same-day stress/rest study. Difference scores (stress-rest for each territory) suggesting Ischemia were larger with rubidium (slope of MIBI/rubidium around 0.45). As has been implied by animal or separate-day-human studies, these segmental analyses with simultaneous examination in patients told that rubidium PET flow studies disclose ischemia more often than MIBI studies and that rest MIBI studies in same-day stress/rest-sequence gave a little larger rest defect than they would have shown.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.194-203
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• 2017

The center of percussion(COP) is the point of an extended massive object attached to a pivot where a perpendicular impact will produce no reactive shock at the pivot. COP is an important concept in the field of vibration and dynamics. In vibration, COP causes reduction of vibration and in dynamics, it brings about maximum speed of an object. Many studies about COP are still in progress. However most of the researches have typically focused on the method of mathematical and numerical anlalysis. In this paper, impact analysis was proved by the mechanical energy method using EDISON co-rotational plane beam transient analysis program. The result expressed in acceleration was the relative magnitude of the impulse, which was the indicator of COP. Then, these results were compared with the reference thesis results for exact consequences. Additionally, parametric study of COP was conducted.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.3
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• pp.133-138
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• 2002

The growth of Au films grown on a Si(100)-2x1 surface and Si films on a Ge(100)-2x1 substrate is studied using Positron-annihilation induced Auger Electron Spectroscopy(PAES), Electron induced Auger Electron Spectroscopy(EAES), and Low Energy Electron Diffraction(LEED). Previous work has shown that PAES is almost exclusively sensitive to the top-most atomic layer due to the trapping of positrons in an image potential well just outside the surface before annihilation. This surface specificity is exploited to profile the surface atomic concentrations during the growth of Au on Si(100) and Si on Ge(100) and EAES provides concentrations averaged over the top 3-10 atomic layers simultaneously. The difference in the probe-depth makes us possible to use PAES and EAES in a complementary fashion to estimate the surface and near surface concentration profiles. The results show that (i) the intermixing of Au and Si atoms occurs during the room temperature deposition, (ii) the segregated Ge layer is observed onto the Si layers deposited at 300k. In addition, the prior adsorption of hydrogen prevents the segregation of Ge on top of the deposited Si and that the hydrogen adsorption is useful in growing a thermally stable structure.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.35 no.2
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• pp.136-142
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• 2024

Objectives: The purpose of this study was to examine the patterns of use of oral aripiprazole treatment in children and adolescents diagnosed with autism spectrum disorder (ASD) at a university medical center in Korea. Methods: We retrospectively reviewed the medical records of 164 outpatient children and adolescents diagnosed with ASD by child and adolescent psychiatrists. Patient demographic characteristics, clinical features, age and dose of aripiprazole treatment, associated adverse events, and concomitant medications, etc. were evaluated. Results: Aripiprazole treatment was initiated at a mean age of 7.64 years, at a mean initial dose of 1.15 mg. Methylphenidate was often co-administered with aripiprazole. The most commonly reported adverse effects were increased appetite and weight gain, which in some cases led to discontinuation of medication. Conclusion: A follow-up study is warranted to evaluate the efficacy and safety of aripiprazole treatment in Korean children and adolescents diagnosed with ASD, and it is crucial to consider their clinical characteristics and response to treatment in the evaluation.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.367-370
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• 2005

Offer of medical treatment service for recovery or preservation of physical spiritual function of elderly people by sudden population graying developing is essential. Therefore, according to increase of elderly's medical treatment demand, medical treatment service request is augmented. Number of medical treatment service utilization wishes to grope medical treatment service support way for elderly residing cloth elevation laying stress on elderly's Aging in Place in increase trend in this research. If decide, is as following : First, national hospital and public health center were concentrated most on Seoul and kyonggi, and there were many hospitals to south of a river nine, Songpagu, Seochogu, and public health center was expose that is one by one to each nine. Second, in the case of Seoul, elderly population ratio was expose that comparatively high Yeongdeungpo, Chongno, Yongsan, west passage nine is few hospital number relatively in elderly's residential area. Third, need that establish elderly full text clinic on part of general hospital or university hospital equipment. Fourth, must do so that can use access as is easy little more in local community to all elderly who need medical treatment service of visit nursing, visit medical examination and treatment etc.. that consist in present public health center.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.148-149
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• 2007

We present the design and fabrication prcoess of a two-axis tilting micromirror device driven by the electrostatic vertical comb actuator. A high aspect-ratio comb actuator is fabricated by multiple DRIE process in order to achieve large scan angle. The proposed fabrication process enables a mirror to be fabricated on the wafer-scale. By bonding a double-side polished (DSP) wafer and a silicon-on-insulator (SOI) wafer together, all actuators on the wafer are completely hidden under the reflectors. Nickel lines are embedded on a Pyrex wafer for the electrical access to numerous electrodes of mirrors. An anodic bonding step is implemented to contact electrical lines with ail electrodes on the wafer at a time. The mechanical angle of a fabricated mirror has been measured to be 1.9 degree and 1.6 degree, respectively, in the two orthogonal axes under driving voltages of 100 V. Also, a $8{\times}8$ array of micromirrors with high fill-factor of 70 % is fabricated by the same fabrication process.

• Journal of Periodontal and Implant Science
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• v.54 no.1
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• pp.13-24
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• 2024

Purpose: This study investigated the adjunctive effect of light-emitting diodes (LEDs) in the treatment of experimental periodontitis. Methods: Experimental periodontitis was induced by placing ligatures around the mandibular second, third, and fourth premolars of 6 beagles for 3 months. After ligature removal, periodontitis progressed spontaneously for 2 months. The animals' hemimandibles were allocated among the following 3 groups: 1) no treatment (control), 2) scaling and root planing (SRP), and 3) SRP with LED irradiation at 470-nm and 630-nm wavelengths (SRP/LED). The probing pocket depth (PPD) and gingival recession (GR) were measured at baseline, 6 weeks, and 12 weeks. The clinical attachment level (CAL) was calculated. After 12 weeks, histological and histomorphometric assessments were performed. The distances from the gingival margin to the apical extent of the junctional epithelium (E) and to the connective tissue (CT) attachment were measured, as was the total length of soft tissue (ST). Results: PPD and CAL increased at 12 weeks compared with baseline in the control group (6.31±0.43 mm to 6.93±0.50 mm, and 6.46±0.60 mm to 7.61±0.78 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP group (6.01±0.59 to 4.81±0.65 mm, and 6.51±0.98 to 5.39±0.93 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP/LED group (6.03±0.39 to 4.46±0.47 mm, and 6.11±0.47 to 4.78±0.57 mm, respectively). The E/ST and CT/ST ratios significantly differed among the 3 groups (P<0.05). The clinical parameters and histologic findings demonstrated that 470-nm and 630-nm wavelength LED irradiation accompanying SRP could improve treatment results. Conclusions: Within the study limitations, 470 nm and 630 nm wavelength LED irradiation might provide additional benefits for periodontitis treatment.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.125-132
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• 1995

The purpose of this study was to establish mononuclear cell cultures such as lymphocytes or buffy coat for the biological dosimetry of in vitro Irradiation of the radionuclide Tc-99m in order to exclude the effect of residual doses seen in the cultures of whole blood. Biological do simetry of Tc-99m on cultured mononuclear cells at doses ranging from 0.05 to 6.00 Gy, by scoring unstable chromosomal aberrations(Ydr) observed in cultured lymphocytes, were performed using peripheral venous blood of healthy normal person. The results showed that; (1) In vitro irradiation of radioisotope in separated lymphocyte or buffy coat showed trace amount of residual doses of isotope after washing. Residual doses of isotopes are increased in proportion to exposed time and irradiated dose without difference between I-131 and Tc-99m. (2) We obtained these linear-quadratic dose response equations in lymphocyte and buffy coat culture after in vitro irradiation of Tc-99m, respectively (Ydr = 0.001949 $D^2$ +0.006279D + 0.000185; Ydr= 0.002531 $D^2$-0.003274 D+0.003488). In conclusion, the linear quadratic dose-response equation from in vitro irradiation of Tc-99m with lymphocyte and buffy coat culture was thought to be useful for assessing Tc-99m induced biological effects. And mono-nuclear cell cultures seem to be the most appropriate experimental model for the assessment of biological dosimetry of internal irradiation of radionuclides.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.5
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• pp.87-98
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• 2020

At the point of implementing policies related to urban heat through the overall environmental assessment of the city using national data, citizen science projects that can collect data in a wide range are emerging for effective policy establishment. Although the utility of citizen data is improving, data quality is a primary concern for researchers employing public participation in scientific research. In this study, validation was conducted based on citizen data acquired in the "Suwon City Heat Map Project", and the applicability to temperature monitoring was confirmed based on the results. As a result of analyzing the validity verification of citizen data using three methods, the data result value is 0.843, RMSE: 0.683℃, and a meaningful value was found within 3km of national data. We found that citizen data utilization is high through the results of this study and These projects are expected to be used as basic data for establishing effective policies or can be reflected in the various planning.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7685-7692
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• 2013

Background: Management of hypertension and diabetes in cancer survivors is an important issue; however, not much is known about the level of management of such chronic disease in Korea. This study therefore assessed the prevalence, awareness, control, and treatment of hypertension and diabetes in Korean cancer survivors compared to non-cancer survivors. Materials and Methods: A cross-sectional design was employed, wherein data were obtained from standardized questionnaires completed by 943 cancer survivors and 41,233 non-cancer survivors who participated in the Fourth and Fifth Korea National Health and Nutrition Examination Surveys (2007-2011). We calculated adjusted proportions for prevalence and management of hypertension and diabetes in non-cancer survivors and cancer survivors. We also assessed the associated factors with prevalence and management of cancer survivors. Results: Cancer survivors are more likely than the general population to have higher prevalence, awareness, treatment, and control of hypertension. However, diabetic management was not significantly higher in cancer survivors than in non-cancer survivors, despite their having a higher prevalence. Several factors, such as, age, drinking, years since cancer diagnosis, self-perceived health status, and specific cancer types were found to affect to management of hypertension and diabetes. Conclusions: These data suggest that cancer survivors appear to be better than non-cancer survivors at management of hypertension, but not diabetes. There is a need for healthcare providers to recognize the importance of long-term chronic disease management for cancer survivors and for the care model to be shared between primary care physicians and oncologists.