• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.352-361
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• 1999

Purpose: Carotid endarterectomy nay benefit patients with bilateral carotid stenosis by improving cerebro-vascular hemodynamics of ipsilateral as well as contralateral cerebral hemispheres. We investigated cerebro-vascular hemodynamics after carotid endarterectomy in patients with contralateral carotid occlusion by acetazolamide stress brain SPECT. Materials and Methods: Subjects were 14 symptomatic patients (all men, mean age 66 yrs) with carotid stenosis (>50%) with contralateral carotid occlusion. Acetazolamide stress Tc-99m ECD brain SPECTs were performed within 2 weeks before and after carotid endarterectomy using one day protocol. Cerebral blood flow (CBF) and cerebrovascular reserve (CVR) were assessed visually. In 12 patients, correlation between the patency of proximal anterior cerebral or anterior communicating arteries (A1/A-comm) and the improvement of CBF or CVR after endarterectomy was assessed. Results: Preoperative SPECT showed reduced CBF in 2 ipsilateral and 10 contralateral hemispheres. CVR was reduced in 4 ipsilateral and 9 contralateral hemispheres. Of 12 hemispheres with reduced CBF, 2 hemispheres (16.7%) showed improvement of CBF after endarterectomy. However, reduced CVR was improved in all 4 ipsilateral and 7 of 9 (78%) of contralateral hemispheres after endarterectomy. Three of4 with stenotic Al/A-comm and 4 of 8 with patent A1/A-comm had reduced contralateral CVR. Reduced contralateral CVR improved in all 3 patients with stenotic A1/A-comm and 3 of 4 with patent A1/A-comm. Conclusion: Acetazolamide stress brain SPECT demonstrated improvement of compromised cerebrovascular reserve in not only ipsilateral but also contralateral hemispheres of patients with contralateral carotid occlusion after carotid endarterectomy, and may, therefore, be useful for evaluating cerebral blood flow and cerebrovascular reserve after carotid endarterectomy.

• Journal of the Institute of Convergence Signal Processing
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• v.16 no.4
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• pp.149-155
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• 2015

Tooth implant is located in oral cavity and affects neck, skull base, and facail image. These magnetic inhomogeneities are usually frequency encoding direction which cause artifacts due to change of signal strength and geometric distortion. First, to evaluate signal to noise ratio (SNR) of magnetic resonance image caused by tooth implant this study uses meat phantom which is similar to human body and is consisted with fat, muscle, and water to measure signal to noise ratio. Second, signal to noise ratio by using custom-made fixed phantom is measured, and then signal to noise ratio size of different tooth implant types is compared and analyzed. The measured signal to noise ratio values of Brushite, HSA, Metal, and RBM for meat phantom were 2.76, 2.22, 1.88, and 1.57 on T1 SE, 1.88, 1.78, 1.65, and 1.79 on T2 FLAIR, 2.28, 2.25, 2.88, and 2.05 on T2 FSE, and 2.74, 1.94, 1.67, and 1.48 on T2 GRE. The measured signal to noise ratio values of Brushite, HSA, Metal, and RBM for fixed water phantom were 1.2, 1.06, 1.12, and 1.22 on DWI, 1.93, 1.87, 1.93, and 2.06 T1 SE, 1.83, 1.76, 1.82, and 1.92 on T2 FLAIR, 1.85, 1.79, 7.86, and 1.97 on T2 FSE, and 1.97, 1.93, 1.99, and 2.06 on T2 GRE. By considering through the results, patients and dentists need to consider some impacts from testing many aspects although their main purpose of having tooth implants is a dental restoration. Moreover, depending on the tooth implant characteristics of individual patients this study results can be used as baseline data when choosing test protocol.

• Korean Journal of Child Education & Care
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• v.18 no.4
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• pp.39-50
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• 2018

Objective: Social attention is paid to the issues concerning child care teachers' work multisibility and ambiguous legal status. Child care teachers are employees based on the "Labor Standards Act" and the "Child Care Act". They also play the role of kindergarten teachers based on the "Childhood Education Act" because of the Nuri curriculum. Based on the main tasks of the child care teachers who protect and nurture infants and toddlers, the Nuri curriculum education for infants is conducted. However, the duties and rights of child care teachers are disproportionate because there are many areas where teachers' professional roles do not suit their legal rights. Methods: The purpose of this study is to investigate how teachers perceive their own rights through field experience using qualitative method based on interpretative epistemology. Participants were 61 child care teachers working in the metropolitan area and used protocol description and focus group interview (FGI) for data collection. The collected data were derived as a central theme according to the data analysis method proposed by Creswell (2013). Results: Participants in the study described the 'Right and autonomy of education as a professional occupation', 'Right to request for improvement on working conditions, guarantee of living and to request for welfare system' and 'Right to guarantee of a teacher's status and adjustment of grievance.' They pointed out poor working conditions and welfare benefits at daycare centers, and emphasized that education and autonomy are necessary conditions to be strengthened for quality child care activities. On the other hand, they did not realize that 'Right to guarantee of a teacher's status and adjustment of grievance' was their right. And they have endured the infringement of this right. Conclusion/Implications: This study reveals the gap between teachers' responsibilities and rights, indicating the urgency of institutional arrangements. It is discussed that the social expectation for strengthening personality and professionalism as an infant and child specialist is increased and a practical alternative for the improvement of the right of teachers working in the child care field is needed considering the change of values about work.

• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.129-140
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• 2017

This study was carried out to develop of environmental risk assessments and the biosafety guide for Vitamin E enhanced transgenic soybean at LMO (Living Modified Organism) isolation field. In LMO quarantine area of National Institute of Agricultural Sciences, insect species diversities and population densities on vitamin E enhanced transgenic soybean and non-GM soybeans (Willams 82 and Seoritae) were investigated. A total of 17,717 individuals of 77 species from 8 orders were collected in LMO isolation field. In three type soybeans field, total of 5,250 individuals in Vitamin E enhanced transgenic soybean, 5,510 individuals in Willams 82, and 6,957 individuals in Seoritae were collected, respectively. There was no difference between the population densities of insect pests, natural enemies and other insects on Vitamin E enhanced transgenic soybean and Willams 82, while natural enemies density on Seoritae was higher than on Vitamin E enhanced transgenic soybean, but insect pests density on Vitamin E enhanced transgenic soybean was higher. These results provided the insects diversity for risk assessment survey of Vitamin E enhanced transgenic soybean and suggested that the guideline could be useful to detect LMO crops.

• Korean Journal of Community Nutrition
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• v.27 no.2
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• pp.121-131
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• 2022

Objectives: This study aimed to examine the effectiveness of the intervention of the nutrition support team (NST) on the nutritional status of critically ill patients. Methods: The medical records of 176 adult patients who were admitted to the intensive care unit and received enteral or parenteral nutrition for more than 7 days were retrospectively analyzed. The patients were classified into the NST and non-NST groups according to whether they were referred to the NST or not. The NST group was further classified into the compliance and non-compliance groups depending on their compliance with the NST recommendations. Results: The NST referral rate was 56.8%, and the rate of compliance with the NST recommendations was 47.0%. Significantly higher energy and protein were provided to the NST and the compliance groups than to the non-NST and the non-compliance groups. The proportion of patients who reached the target calories after the initiation of enteral nutrition was significantly higher in the NST and the compliance groups than in the non-NST and the non-compliance groups. The serum albumin and hemoglobin levels significantly decreased in every group, but the changes were significantly lower in the compliance group. The nutritional status at discharge from the intensive care unit compared to the status at admission was significantly worse in the NST, non-NST, and non-compliance groups. However, the status was maintained in the compliance group. The length of stay in the intensive care unit was significantly shorter in the compliance group. Conclusions: Compliance with the NST recommendations was found to provide more calories and protein and prevent the deterioration of the nutritional status of critically ill patients. Therefore, effective communication between medical staff and the NST from the early stages of admission to the intensive care unit is needed to improve referrals to the NST and compliance with the recommendations.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.334-346
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• 2022

There is a lack of knowledge and information on the understanding and application of the Process Safety Management (PSM) system, recognized as a major cause of industrial accidents in small-and medium-sized workplaces. Hence, it is necessary to prepare a protocol to secure the practical and continuous levels of implementation for PSM and eliminate human errors through tracking management. However, insufficient research has been conducted on this. Therefore, this study investigated and analyzed the various violations in the administrative measures, based on the regulations announced by the Ministry of Employment and Labor, in approximately 200 small-and medium-sized PSM workplaces with fewer than 300 employees across in korea. This study intended to contribute to the prevention of major industrial accidents by developing a facility maintenance web program that removed human errors in small-and medium-sized workplaces. The major results are summarized as follows. First, It accessed the web via a QR code on a smart device to check the equipment's specification search function, cause of failure, and photos for the convenience of accessing the program, which made it possible to make requests for the it inspection and maintenance in real time. Second, it linked the identification of the targets to be changed, risk assessment, worker training, and pre-operation inspection with the program, which allowed the administrator to track all the procedures from start to finish. Third, it made it possible to predict the life of the equipment and verify its reliability based on the data accumulated through the registration of the pictures for improvements, repairs, time required, cost, etc. after the work was completed. It is suggested that these research results will be helpful in the practical and systematic operation of small-and medium-sized PSM workplaces. In addition, it can be utilized in a useful manner for the development and dissemination of a facility maintenance web program when establishing future smart factories in small-and medium-sized PSM workplaces under the direction of the government.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.72-81
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• 2024

Purpose: This study aimed to assess the marginal and internal fit of 3-unit monolithic zirconia fixed partial dentures (FPDs) fabricated via computer-aided design and computer-aided manufacturing (CAD/CAM) from solid working casts and removable die system. Materials and Methods: The tooth preparation protocol for a zirconia crown was executed on the mandibular right first premolar and mandibular right first molar, with the creation of a reference cast featuring an absent mandibular right second premolar. The reference cast was duplicated using polyvinyl siloxane impression, from which 20 working casts were fabricated following typical dental laboratory procedures. For comparative analysis, 10 FPDs were produced from a removable die system (RD group) and the remaining 10 FPDs from the solid working casts (S group). The casts were digitized using a dental desktop scanner to establish virtual casts and design the FPDs using CAD. The definitive 3-unit monolithic zirconia FPDs were fabricated via a CAM milling process. The seated FPDs on the reference cast underwent digital evaluation for marginal and internal fit. The Mann-Whitney U test was applied for statistical comparison between the two groups (α = 0.05). Results: The RD group showed significantly higher discrepancies in fit for both premolars and molars compared to the S group (P < 0.05), particularly in terms of marginal and occlusal gaps. Color mapping also highlighted more significant deviations in the RD group, especially in the marginal and occlusal regions. Conclusion: The study found that the discrepancies in marginal and occlusal fits of 3-unit monolithic zirconia FPDs were primarily associated with those fabricated using the removable die system. This indicates the significant impact of the fabrication method on the accuracy of FPDs.

• Radiation Oncology Journal
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• v.22 no.4
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• pp.237-246
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• 2004

Purpose: To investigate the effects of radiation dose-escalation on the treatment outcome, complications and the other prognostic variables for glioblastoma patients treated with 3D-conformal radiotherapy (3D-CRT). Materials and Methods: Between Jan 1997 and July 2002, a total of 75 patients with histologically proven diagnosis of glioblastoma were analyzed. The patients who had a Karnofsky Performance Score (KPS) of 60 or higher, and received at least 50 Gy of radiation to the tumor bed were eligible. All the patients were divided into two arms; Arm 1, the high-dose group was enrolled prospectively, and Arm 2, the low-dose group served as a retrospective control. Arm 1 patients received $63\~70$ Gy (Median 66 Gy, fraction size $1.8\~2$ Gy) with 3D-conformal radiotherapy, and Arm 2 received 59.4 Gy or less (Median 59.4 Gy, fraction size 1.8 Gy) with 2D-conventional radiotherapy. The Gross Tumor Volume (GTV) was defined by the surgical margin and the residual gross tumor on a contrast enhanced MRI. Surrounding edema was not included in the Clinical Target Volume (CTV) in Arm 1, so as to reduce the risk of late radiation associated complications; whereas as in Arm 2 it was included. The overall survival and progression free survival times were calculated from the date of surgery using the Kaplan-Meier method. The time to progression was measured with serial neurologic examinations and MRI or CT scans after RT completion. Acute and late toxicities were evaluated using the Radiation Therapy Oncology Group neurotoxicity scores. Results: During the relatively short follow up period of 14 months, the median overall survival and progression free survival times were $15{\pm}1.65$ and $11{\pm}0.95$ months, respectively. The was a significantly longer survival time for the Arm 1 patients compared to those in Arm 2 (p=0.028). For Arm 1 patients, the median survival and progression free survival times were $21{\pm}5.03$ and $12{\pm}1.59$ months, respectively, while for Arm 2 patients they were $14{\pm}0.94$ and $10{\pm}1.63$ months, respectively. Especially in terms of the 2-year survival rate, the high-dose group showed a much better survival time than the low-dose group; $44.7\%$ versus $19.2\%$. Upon univariate analyses, age, performance status, location of tumor, extent of surgery, tumor volume and radiation dose group were significant factors for survival. Multivariate analyses confirmed that the impact of radiation dose on survival was independent of age, performance status, extent of surgery and target volume. During the follow-up period, complications related directly with radiation, such as radionecrosis, has not been identified. Conclusion: Using 3D-conformal radiotherapy, which is able to reduce the radiation dose to normal tissues compared to 2D-conventional treatment, up to 70 Gy of radiation could be delivered to the GTV without significant toxicity. As an approach to intensify local treatment, the radiation dose escalation through 3D-CRT can be expected to increase the overall and progression free survival times for patients with glioblastomas.