• Title/Summary/Keyword: 통계해석

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Physiological and Psychological analysis of musculoskeletal symptoms (근골격계질환에 대한 물리적/심리적요인에 대한 연구)

  • Donghyun Park;Sung Kyu Bae
    • Korean Journal of Culture and Social Issue
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    • v.9 no.spc
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    • pp.107-122
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    • 2003
  • The object of this study is to evaluate the prevailing physical and psychosocial conditions regarding occupational low back injury. This study consists of two parts. In the first part of the study, analytic biomechanical model and NIOSH guidelines are applied to evaluate risk levels of low back injury for automobile assembly jobs. Total of 246 workers are analysed. There are 20 jobs having greater back compressive forces than 300kg at L5/S1. Also, there are 44 jobs over Action Limit with respect to 1981 NIOSH guidelines. The relationship between psychosocial factors and low back injury was examined in the second part of the study. A battery of questionnaires concerning the psychosocial stress based on PWI (Psychosocial Well-being Index) and musculoskeletal pain symptoms at low back was completed by 246 workers at the same plant. Results showed that 207 out 246 workers experienced the symptoms and 27 workers were diagnosed as patients. Two groups(low stressed, high stressed) based on PWI score had no significant relationships with both symptoms and results of diagnosis. The relationships between physical work load and psychosocial stress were also analysed. Specifically, some postural factors(vertical deviation angle of forearm, horizontal deviation angle of upperarm, vertical deviation angle of thigh, etc) were highly correlated with psychosocial stress. The results illustrated that PWI scores were associated with some physical workloads. However, psychosocial stress levels couldn't be well related with the pain symptom as well as the actual incidence of low back injury since pain or discomfort regarding low back injury were more complex than that of other musculoskeletal disorders.

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The Effect on Use Satisfaction and Revisit Intention of Spatial Storytelling Components in Historical Theme Park - Focused on Samgukyusa Theme Park in Gunwi-Gun - (역사테마파크 공간스토리텔링 구성인자가 이용만족도 및 재방문의사에 미치는 영향 - 군위 삼국유사테마파크를 중심으로 -)

  • Kim, Oh-yeon;An, Seung-Hong
    • Journal of the Korean Institute of Landscape Architecture
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    • v.52 no.2
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    • pp.64-78
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    • 2024
  • Storytelling is a communication technique to express and convey the story using various media, where the audience accepts the story, reinterprets the topic and interacts with the storyteller. It was assumed that the user's significance and awareness about the storytelling technique applied to historical theme parks would have an impact on the satisfaction of using the theme park and intention to revisit. In this study, it was purposed to derive the structural factors of spatial storytelling in historical theme parks, and to understand the impact of user's awareness and constituent factors on user responses. Based on previous researches, the structural factors of spatial storytelling in historical theme parks were derived related to theme, experientiality, unusualness, educationalness, unity, expressiveness, interactivity, and interest, and for which the users' awareness was surveyed. The survey was conducted targeting the users of Samguk Yusa Theme Park located in Gunwi-gun, Gyeongsangbuk-do, where the collected data was analyzed using EXCEL2020 and SPSS 21.0 statistical programs, and the results are as follows: First, the spatial storytelling technique applied as a conveying method of the theme of Samguk Yusa Theme Park affects users' satisfaction and intention to revisit, and most respondents responded that the storytelling was significant. Second, it showed that the significance of unusualness and educationalness among the awareness of significance of the spatial storytelling constituent factors of Samguk Yusa Theme Park has a significant impact on user's satisfaction, and the significance of unusualness, interactivity, educationalness, and interest has a significant impact on intention to revisit. Third, it showed that the awareness of interest, theme, and unity has a significant impact on user's satisfaction depending on the user's awareness of spatial storytelling constituent factors of Samguk Yusa Theme Park, and the awareness of interactivity and experientiality has a significant impact on intention to revisit. This study is meaningful in quantitative analysis and interpretation of the influence of storytelling on user's response to historical theme parks by the exploratory analysis of characteristic factors and spatial storytelling constituent factors on historical theme parks and deriving the structural factors of spatial storytelling in historical theme parks.

The Impact of Social Capital and Laboratory Startup Team Diversity on Startup Performance Based on a Network Perspective: Focusing on the I-Corps Program (네트워크 관점에 기반한 사회적 자본 및 실험실 창업팀 다양성이창업 성과에 미치는 영향: I-Corps program을 중심으로)

  • Lee, Jai Ho;Sohn, Youngwoo;Han, Jung Wha;Lee, Sang-Myung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.6
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    • pp.173-189
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    • 2023
  • As supreme technologies continue to be developed, industries such as artificial intelligence, biotechnology, robots, aerospace, electric vehicles, and solar energy are created, and the macro business environment is rapidly changing. Due to these large-scale changes and increased complexity, it is necessary to pay attention to the effect of social capital, which can create new value by utilizing capital increasing the importance of relationships rather than technology or asset ownership itself at the level of start-up strategy. Social capital is a concept first proposed by Hanifan in 1916, and refers to the overall sum of capabilities or resources that are latent or available for use in mutual, continuous, organic relationships or accumulated human relationship networks between individuals or social members. In addition, the diversity of start-up teams with diverse backgrounds, characteristics, and capabilities, rather than one exceptional founder, has been emphasized. Founding team diversity refers to the diversity of in-depth factors such as demographic factors, beliefs, and values of the founding team. In addition, changes in the macro environment are emphasizing the importance of technology start-ups and laboratory start-ups that lead industrial innovation and create the nation's core growth engines. This study focused on the I-Corps' program. I-Corps, which means innovation corps, is a laboratory startup program launched by the National Research Foundation (NSF) in 2011 to encourage entrepreneurship and commercialization of research results. It focuses on forming a startup team involving professors, researchers and market discovery activities. Taking these characteristics into account, this study empirically verified the impact of social capital from a network perspective and founding team diversity on I-Corps start-up performance. As a result of the analysis, the educational diversity of the founding team had a negative (-) effect on the financial performance of the founding team. On the other side, the gender diversity and the cognitive dimension of social capital had a positive (+) effect on the financial performance of the founding team. This study is expected to provide more useful theoretical and practical implications regarding the diversity, social capital, and performance interpretation of the I-Corps Lab startup team.

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Multi-classification of Osteoporosis Grading Stages Using Abdominal Computed Tomography with Clinical Variables : Application of Deep Learning with a Convolutional Neural Network (멀티 모달리티 데이터 활용을 통한 골다공증 단계 다중 분류 시스템 개발: 합성곱 신경망 기반의 딥러닝 적용)

  • Tae Jun Ha;Hee Sang Kim;Seong Uk Kang;DooHee Lee;Woo Jin Kim;Ki Won Moon;Hyun-Soo Choi;Jeong Hyun Kim;Yoon Kim;So Hyeon Bak;Sang Won Park
    • Journal of the Korean Society of Radiology
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    • v.18 no.3
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    • pp.187-201
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    • 2024
  • Osteoporosis is a major health issue globally, often remaining undetected until a fracture occurs. To facilitate early detection, deep learning (DL) models were developed to classify osteoporosis using abdominal computed tomography (CT) scans. This study was conducted using retrospectively collected data from 3,012 contrast-enhanced abdominal CT scans. The DL models developed in this study were constructed for using image data, demographic/clinical information, and multi-modality data, respectively. Patients were categorized into the normal, osteopenia, and osteoporosis groups based on their T-scores, obtained from dual-energy X-ray absorptiometry, into normal, osteopenia, and osteoporosis groups. The models showed high accuracy and effectiveness, with the combined data model performing the best, achieving an area under the receiver operating characteristic curve of 0.94 and an accuracy of 0.80. The image-based model also performed well, while the demographic data model had lower accuracy and effectiveness. In addition, the DL model was interpreted by gradient-weighted class activation mapping (Grad-CAM) to highlight clinically relevant features in the images, revealing the femoral neck as a common site for fractures. The study shows that DL can accurately identify osteoporosis stages from clinical data, indicating the potential of abdominal CT scans in early osteoporosis detection and reducing fracture risks with prompt treatment.

The Characteristics and Performances of Manufacturing SMEs that Utilize Public Information Support Infrastructure (공공 정보지원 인프라 활용한 제조 중소기업의 특징과 성과에 관한 연구)

  • Kim, Keun-Hwan;Kwon, Taehoon;Jun, Seung-pyo
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.1-33
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    • 2019
  • The small and medium sized enterprises (hereinafter SMEs) are already at a competitive disadvantaged when compared to large companies with more abundant resources. Manufacturing SMEs not only need a lot of information needed for new product development for sustainable growth and survival, but also seek networking to overcome the limitations of resources, but they are faced with limitations due to their size limitations. In a new era in which connectivity increases the complexity and uncertainty of the business environment, SMEs are increasingly urged to find information and solve networking problems. In order to solve these problems, the government funded research institutes plays an important role and duty to solve the information asymmetry problem of SMEs. The purpose of this study is to identify the differentiating characteristics of SMEs that utilize the public information support infrastructure provided by SMEs to enhance the innovation capacity of SMEs, and how they contribute to corporate performance. We argue that we need an infrastructure for providing information support to SMEs as part of this effort to strengthen of the role of government funded institutions; in this study, we specifically identify the target of such a policy and furthermore empirically demonstrate the effects of such policy-based efforts. Our goal is to help establish the strategies for building the information supporting infrastructure. To achieve this purpose, we first classified the characteristics of SMEs that have been found to utilize the information supporting infrastructure provided by government funded institutions. This allows us to verify whether selection bias appears in the analyzed group, which helps us clarify the interpretative limits of our study results. Next, we performed mediator and moderator effect analysis for multiple variables to analyze the process through which the use of information supporting infrastructure led to an improvement in external networking capabilities and resulted in enhancing product competitiveness. This analysis helps identify the key factors we should focus on when offering indirect support to SMEs through the information supporting infrastructure, which in turn helps us more efficiently manage research related to SME supporting policies implemented by government funded institutions. The results of this study showed the following. First, SMEs that used the information supporting infrastructure were found to have a significant difference in size in comparison to domestic R&D SMEs, but on the other hand, there was no significant difference in the cluster analysis that considered various variables. Based on these findings, we confirmed that SMEs that use the information supporting infrastructure are superior in size, and had a relatively higher distribution of companies that transact to a greater degree with large companies, when compared to the SMEs composing the general group of SMEs. Also, we found that companies that already receive support from the information infrastructure have a high concentration of companies that need collaboration with government funded institution. Secondly, among the SMEs that use the information supporting infrastructure, we found that increasing external networking capabilities contributed to enhancing product competitiveness, and while this was no the effect of direct assistance, we also found that indirect contributions were made by increasing the open marketing capabilities: in other words, this was the result of an indirect-only mediator effect. Also, the number of times the company received additional support in this process through mentoring related to information utilization was found to have a mediated moderator effect on improving external networking capabilities and in turn strengthening product competitiveness. The results of this study provide several insights that will help establish policies. KISTI's information support infrastructure may lead to the conclusion that marketing is already well underway, but it intentionally supports groups that enable to achieve good performance. As a result, the government should provide clear priorities whether to support the companies in the underdevelopment or to aid better performance. Through our research, we have identified how public information infrastructure contributes to product competitiveness. Here, we can draw some policy implications. First, the public information support infrastructure should have the capability to enhance the ability to interact with or to find the expert that provides required information. Second, if the utilization of public information support (online) infrastructure is effective, it is not necessary to continuously provide informational mentoring, which is a parallel offline support. Rather, offline support such as mentoring should be used as an appropriate device for abnormal symptom monitoring. Third, it is required that SMEs should improve their ability to utilize, because the effect of enhancing networking capacity through public information support infrastructure and enhancing product competitiveness through such infrastructure appears in most types of companies rather than in specific SMEs.

Relationship between Broca Index of Late School-Aged Children and Their Mothers' Eating, Cooking, and Exercise Habit (어머니의 식습관, 요리습관 및 운동습관과 학령기 후기 아동의 Broca 체질량지수와의 상관관계 연구)

  • Lee, Hyerim;Lee, Kyoung-Eun;Ko, Kwang Suk;Hong, Eunah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.10
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    • pp.1488-1496
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    • 2016
  • The purposes of this study were to analyze mothers' eating, cooking, and exercise habits based on their demographic characteristics and to examine the relationship between those habits and their late school-aged children's Broca index. A total of 393 questionnaires were mailed to the mothers of late school-aged children who registered at four elementary schools in the Seoul area, of which 159 participants (40.0%) completed questionnaires. Statistical data analyses were performed using SPSS/Win 21.0 for descriptive statistics, t-test ANOVA, and Pearson's regression coefficient. There was a statistically significant difference in mothers' cooking habit (F=3.920, P=0.022) and exercise habit (F=3.211, P=0.043) according to their educational level. Interestingly, 82.4% of mothers had a Broca index of less than 90% of normal body mass level. A significant positive correlation of Broca index between mothers and their late school-aged children (r=0.345, P<0.001) indicated that children whose mothers had a low body mass level also tended to have a low body mass level. In this study, late school-aged children's Broca index was not significantly related with mother's eating (r=-0.072, P=0.367) or exercise habits (r=-0.010, P=0.897) but was significantly related with their mother's cooking habits (r=-0.157, P=0.048). Considering there are few studies examining the impacts of mother's cooking habits on their children's appropriate body mass, the results suggest that developing an effective educational program to cultivate mothers' healthy cooking habits to improve school-aged children's health status is very important. The findings of this study provide important data that could be used when developing health education programs tailored to the multi-dimensional impacts of mothers' life habits on their last school-aged children's developmental health status.

Effects of Anti-thyroglobulin Antibody on the Measurement of Thyroglobulin : Differences Between Immunoradiometric Assay Kits Available (면역방사계수법을 이용한 Thyroglobulin 측정시 항 Thyroglobulin 항체의 존재가 미치는 영향: Thyroglobulin 측정 키트에 따른 차이)

  • Ahn, Byeong-Cheol;Seo, Ji-Hyeong;Bae, Jin-Ho;Jeong, Shin-Young;Yoo, Jeong-Soo;Jung, Jin-Hyang;Park, Ho-Yong;Kim, Jung-Guk;Ha, Sung-Woo;Sohn, Jin-Ho;Lee, In-Kyu;Lee, Jae-Tae;Kim, Bo-Wan
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.4
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    • pp.252-256
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    • 2005
  • Purpose: Thyroglobulin (Tg) is a valuable and sensitive tool as a marker for diagnosis and follow-up for several thyroid disorders, especially, in the follow-up of patients with differentiated thyroid cancer (DTC). Often, clinical decisions rely entirely on the serum Tg concentration. But the Tg assay is one of the most challenging laboratory measurements to perform accurately owing to antithyroglobulin antibody (Anti-Tg). In this study, we have compared the degree of Anti-Tg effects on the measurement of Tg between availale Tg measuring kits. Materials and Methods: Measurement of Tg levels for standard Tg solution was performed with two different kits commercially available (A/B kits) using immunoradiometric assay technique either with absence or presence of three different concentrations of Anti-Tg. Measurement of Tg for patient's serum was also performed with the same kits. Patient's serum samples were prepared with mixtures of a serum containing high Tg levels and a serum containg high Anti-Tg concentrations. Results: In the measurements of standard Tg solution, presence of Anti-Tg resulted in falsely lower Tg level by both A and B kits. Degree of Tg underestimation by h kit was more prominent than B kit. The degree of underestimation by B kit was trivial therefore clinically insignificant, but statistically significant. Addition of Anti-Tg to patient serum resulted in falsely lower Tg levels with only A kit. Conclusion: Tg level could be underestimated in the presence of anti-Tg. Anti-Tg effect on Tg measurement was variable according to assay kit used. Therefore, accuracy test must be performed for individual Tg-assay kit.

Comparison of Treadmill and Cycle Ergometer in Male Korean College Students (한국 남자 대학생을 대상으로 시행한 Cardiopulmonary Exercise Test에서 Treadmill과 Cycle Ergometer의 비교 분석)

  • Chang, Yoon-Soo;Park, Jae-Min;Choi, Seung-Won;Ahn, Gang-Hyun;Lee, Jun-Gu;Yang, Dong-Kyu;Kim, Se-Kyu;Chang, Jun;Ahn, Chul-Min;Kim, Seong-Kyu;Lee, Won-Yong
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.1
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    • pp.26-34
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    • 1999
  • Background : Generally $VO_2$ max is higher in treadmill exercise than cycle ergometer exercise. According to Hassen and Wasserman, $VO_2$ max with treadmill exercise is higher at ratio of 1.11 than that with cycle ergometer. $VO_2$ max also is influenced by race, sociocultural background, exercise habit In this study, $VO_2$ max and AT were evaluated between Treadmill and cycle exercise in male Korean college students. Method: Study subjects were 44 male college students. We randomized them into 2 groups; 24 students did treadmill exercise at first and 1 week later did cycle ergometer. Another 20 students did in opposite method. They made symptom limited maximal exercise. Author defined maximal exercise as followings: 1) respiratory exchange ratio(RER)> 1.1, 2) plateau>30 sec, 3) heart rate reserve(HRR) <15%, or 4) breathing reserve (BR)<30%. Otherwise their results are excluded as submaximal exercise. Anaerobic threshold(AT) was estimated by V-slope method. Results: $VO_2$ max and AT was $45.1{\pm}6.66m\ell$/kg/min and $26.0{\pm}6.78m\ell$/kg/min in treadmill and $34.9{\pm}5.89m\ell$/kg/min, $19.5{\pm}4.77m\ell$/kg/min in Cycle Ergometer. The measured-$VO_2max$/pred-$VO_2max$ was $98.8{\pm}13.24%$ in treadmill; $84.4{\pm}13.42%$ in cycle ergometer. Comparing $VO_2$ max in treadmill with that obtained by Hassen's method, there were significant differences.(p<0.01). At maximal exercise there were differences in HRR, $O_2$/pulse, BR, $V_E$/MVV, $V_E/VCO_2$ between treadmill and cycle but not in $V_E/VO_2$, Vd/Vt, Ti/Ttot. At AT there were differences in $O_2$/pulse, BR, $V_E$/MVV, Ti/Ttot between treadmill and cycle, otherwise not. Conclusion: According to the result of this study, there are larger gap between treadmill and cycle ergometer in normal Korean adults than foreign data, and it needs further study to obtain reference value of Korea.

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Crystal Structures of Full Dehydrated $Ca_{35}Cs_{22}Si_{100}Al_{92}O_{384}$and $Ca_{29}Cs_{34}Si_{100}Al_{92}O_{384}$ ($Ca^{2+}$ 이온과 $Cs^+$ 이온으로 치환되고 탈수된 두개의 제올라이트 X $Ca_{35}Cs_{22}Si_{100}Al_{92}O_{384}$$Ca_{29}Cs_{34}Si_{100}Al_{92}O_{384}$의 결정구조)

  • Jang, Se Bok;Song, Seung Hwan;Kim, Yang
    • Journal of the Korean Chemical Society
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    • v.40 no.6
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    • pp.427-435
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    • 1996
  • The structures of fully dehydrated $Ca^{2+}$- and $Cs^+$-exchanged zeolite X, $Ca_{35}Cs_{22}Si_{100}Al_{92}O_{384}$($Ca_{35}Cs_{22}$-X; a=25.071(1) $\AA)$ and $Ca_{29}Cs_{34}Si_{100}Al_{92}O_{384}$($Ca_{29}Cs_{34}$-X; a=24.949(1) $\AA)$, have been determined by single-crystal X-ray diffraction methods in the cubic space group Fd3 at $21(1)^{\circ}C.$ Their structures were refined to the final error indices $R_1$=0.051 and $R_2$=0.044 with 322 reflections for $Ca_{35}Cs_{22}$-X, and $R_1$=0.058 and $R_2$=0.055 with 260 reflections for $Ca_{29}Cs_{34}$-X; $I>3\sigma(I).$ In both structures, $Ca^{2+}$ and $Cs^+$ ions are located at five different crystallographic sites. In dehydrated $Ca_{35}Cs_{22}$-X, sixteen $Ca^{2+}$ ions fill site I, at the centers of the double 6-rings(Ca-O=2.41(1) $\AA$ and $O-Ca-O=93.4(3)^{\circ}).$ Another nineteen $Ca^{2+}$ ions occupy site II (Ca-O=2.29(1) $\AA$, O-Ca-O=118.7(4)') and ten $Cs^+$ ions occupy site II opposite single six-rings in the supercage; each is $1.95\AA$ from the plane of three oxygens (Cs-O=2.99(1) and $O-Cs-O=82.3(3)^{\circ}).$ About three $Cs^+$ ions are found at site II', 2.27 $\AA$ into sodalite cavity from their three-oxygen plane (Cs-O=3.23(1) $\AA$ and $O-Cs-O=75.2(3)^{\circ}).$ The remaining nine $Cs^+$ ions are statistically distributed over site Ⅲ, a 48-fold equipoint in the supercages on twofold axes (Cs-O=3.25(1) $\AA$ and Cs-O=3.49(1) $\AA).$ In dehydrated $Ca_{29}Cs_{34}$-X, sixteen $Ca^{2+}$ ions fill site I(Ca-O=2.38(1) $\AA$ and $O-Ca-O=94.1(4)^{\circ})$ and thirteen $Ca^{2+}$ ions occupy site II (Ca-O=2.32(2) $\AA$, $O-Ca-O=119.7(6)^{\circ}).$ Another twelve $Cs^+$ ions occupy site II; each is $1.93\AA$ from the plane of three oxygens (Cs-O=3.02(1) and $O-Cs-O=83.1(4)^{\circ})$ and seven $Cs^+$ ions occupy site II'; each is $2.22\AA$ into sodalite cavity from their three-oxygen plane (Cs-O=3.21(2) and $O-Cs-O=77.2(4)^{\circ}).$ The remaining sixteen $Cs^+$ ions are found at III site in the supercage (Cs-O=3.11(1) $\AA$ and Cs-O=3.46(2) $\AA).$ It appears that $Ca^{2+}$ ions prefer sites I and II in that order, and that $Cs^+$ ions occupy the remaining sites, except that they are too large to be stable at site I.

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Different Uptake of Tc-99m ECD and Tc-99m HMPAO in the Normal Brains: Analysis by Statistical Parametric Mapping (정상 뇌 혈류 영상에서 방사성의약품에 따라 혈류 분포에 차이가 있는가: 통계적 파라미터 지도를 사용한 분석)

  • Kim, Euy-Neyng;Jung, Yong-An;Sohn, Hyung-Sun;Kim, Sung-Hoon;Yoo, Ie-Ryung;Chung, Soo-Kyo
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.4
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    • pp.244-254
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    • 2002
  • Purpose: This study investigated the differences between technetium-99m ethyl cysteinate dimer (Tc-99m ECD) and technetium-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) uptake in the normal brain by means of statistical parametric mapping (SPM) analysis. Materials and Methods: We retrospectively analyzed age and sex matched 53 cases of normal brain SPECT. Thirty-two cases were obtained with Tc-99m ECD and 21 cases with Tc-99m HMPAO. There were no abnormal findings on brain MRIs. All of the SPECT images were spatially transformed to standard space, smoothed and globally normalized. The differences between the Tc-99m ECD and Tc-99m HMPAO SPECT images were statistically analyzed using statistical parametric mapping (SPM'99) software. The differences bgetween the two groups were considered significant ant a threshold of corrected P values less than 0.05. Results: SPM analysis revealed significantly different uptakes of Tc-99m ECD and Tc-99m HMPAO in the normal brains. On the Tc-99m ECD SPECT images, relatively higher uptake was observed in the frontal, parietal and occipital lobes, in the basal ganglia and thalamus, and in the superior region of the cerebellum. On the Tc-99m HMPAO SPECT images, relatively higher uptakes was observed in subcortical areas of the frontal region, temporal lobe, and posterior portion of inferior cerebellum. Conclusion: Uptake of Tc-99m ECD and Tc-99m HMPO in the normallooking brain was significantly different on SPM analysis. The selective use of Tc-99m ECD of Tc-99m HMPAO in brain SPECT imaging appears especially valuable for the interpretation of cerebral perfusion. Further investigation is necessary to determine which tracer is more accurate for diagnosing different clinical conditions.