• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.36-40
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• 2011

Purpose: $^{18}F$-FDG injected dose to the patient is quite different between the recommended dose from manufacturer and the actual dose applied to each of hospitals. injection of inappropriate $^{18}F$-FDG dose may not only increase the exposed dose to patients but also reduce the image quality. we thus evaluated the proper $^{18}F$-FDG injected dose to decrease the exposed dose to patients considering the image quality. Materials And Methods: NEMA Nu2-1994 phantom was filled with $^{18}F$-FDG increasing hot cylinder radioactivity concentration to 1, 3, 5, 7, 9 MBq/kg based on the ratio of 4:1 between the hot cylinder and background activity. after completing the transmission scan using ct, emission scan was acquired in 3D mode for 2 minutes 30 seconds/bed. ROI was set up on hot cylinder and background radioactivity region. after measuring $SUV_{max}$ those regions, then analyzed SNR at the points. clinical experiment has been conducted the object of patients who have came to smc from november 2009 to august 2010, 97 patients without having a hepatic lesions were selected. ROI was set up in the liver and thigh area. after measuring $SUV_{max}$, the image quality was compared following the injected dose. Results: in phantom study, as the injected radioactivity concentration per unit mass was 1, 3, 5, 7, 9 MBq/kg, $SUV_{max}$ was 23.1, 24.1, 24.3, 22.8, 23.6 and SNR was shown 0.48, 0.54, 0.56, 0.55, 0.55. according to increment of the injected dose, $SUV_{max}$ and SNR was increased under 5 MBq/kg but they were decreased over 7 MBq/kg. in case of clinical experiment, as increased the injected radioactivity concentration per unit mass was 4.72, 5.34, 6.16, 7.41, 8.68 MBq/kg, $SUV_{max}$ was 2.68, 2.67, 2.26, 1.88, 1.95 and SNR was shown 0.52, 0.53, 0.46, 0.46, 0.44. if the injected dose exceeds 5 MBq/kg, showed a decrease pattern as phantom study. Conclusion: increasing $^{18}F$-FDG injected dose considered patient's body weight improve image quality within a certain range. if it exceeds the range, it can be reduced image quality due to random and scatter coincidences. this study indicates that the optimal injected dose was 5 MBq/kg per unit mass the injected radioactivity concentration in 3d wb pet/ct.

• Management & Information Systems Review
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• v.29 no.4
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• pp.143-167
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• 2010

Diverse research topics relating to Social Network Services (SNS) such as, social affective factors in relationships among internet users, social capital value of SNS, comparing attributes why users are intending to participate in SNS, user's lifestyle and their preferences, and the exploratory seeking potential of SNS as a social capital need to be focused on. However, these researches that have been undertaken only consider facts at a particular period of the changing computing environment. In accordance with this indispensability, the integrated view on what technical, social and business characteristics and attributes need to be acknowledged. The purpose of this study is to analyze the evolving attributes and characteristics of SNS from Web 1.0 to Mobile web 2.0 through the Web 2.0 and Mobile 1.0 period. Based on the relevant literature, the attributes that drive the changing technological, social and business aspects of SNS have been developed and analyzed. This exploratory study analyzed major attributes and relationships between SNS and users by changing the paradigms which represented each period. It classified and chronicled each period by representing paradigms and deducted the attributes by considering three aspects such as technological, social and business administration. The major findings of this study are, firstly, the web based computing environment has been changed into the platform attribute for users in the aspect of technology. Users can only read, listen and view information through the web site in the early stages, but now it is possible that users can create, modify and distribute all kinds of information. Secondly, the few knowledge producers of web services have been changed into a collective intelligence by groups of people in the aspect of society. Information authority has been distributed and there is no limit to its spread. Many businesses recognized the potential of the SNS and they are considering how to utilize these advantages toward channel of promotion and marketing. Thirdly, the conventional marketing channel has been changed into oral transmission by using SNS. The market of innovative mobile technology such as smart phones, which provide convenience and access-ability toward customers, has been enlarged. New opportunities to build friendly relationship between business and customers as a new marketing chance have been created. Finally, the role of the consumer has been changed into the leading role of a prosumer. Users can create, modify and distribute information, and are performing the dual role of customer and producer.

• Progress in Medical Physics
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• v.22 no.4
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• pp.206-215
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• 2011

The purpose of this was to investigate the measurement of fluence dose map for the specific patient quality assurance. The measurement of fluence map was performed using 2D matrixx detector. The absorbed dose was measured by a glass detector, Gafchromic film and ion chamber in Hybrid Optimized VMAT Phantom (HOVP). For 2D Matrixx, the results of comparison were average passing rate $85.22%{\pm}1.7$ (RT_Target), $89.96%{\pm}2.15$ (LT_Target) and $95.14%{\pm}1.18$ (G4). The dose difference was $11.72%{\pm}0.531$, $-11.47%{\pm}0.991$, $7.81%{\pm}0.857$, $-4.14%{\pm}0.761$ at the G1, G2, G3, G4. In HOVP, the results of comparison for film were average passing rate (3%, 3 mm) $93.64%{\pm}3.87$, $90.82%{\pm}0.99$. We were measured an absolute dose in steep gradient area G1, G2, G3, G4 using the glass detector. The difference between the measurement and calculation are 8.3% (G1), -5.4% (G2), 6.1% (G3), 7.2% (G4). The using an Ion-chamber were an average relative dose error $-1.02%{\pm}0.222$ (Rt_target), $0.96%{\pm}0.294$ (Lt_target). Though we need a more study using a transmission detector. However, a measurement of real-time fluence map will be predicting a dose for real-time specific patient quality assurance in volume modulated arc therapy.

• Journal of agricultural medicine and community health
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• v.37 no.1
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• pp.1-11
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• 2012

Objectives: To survey the awareness of patient to scrub typhus to provide data for education and communication concerning scrub typhus. Methods: Patients with scrub typhus (case group, n=299) and people without scrub typhus within the previous 2 years (control group, n=598) were matched for age (within 5 years), gender, and occupation (farmer or non-farmer). The participants were recruited from 15 study areas between October and December 2006. Results: The awareness rate of scrub typhus was 75.1%, and was significantly higher than in the case group (79.4% vs. 66.6%, respectively; p<0.01). The major routes of awareness were from 'past history of scrub typhus in family members or neighbors' (54.9%), 'television' (28.3%), and their past history of scrub typhus (5.5%). The average correct rate of scrub typhus was 48.4%, and the correct response rate of cases was significantly higher than controls (p<0.01). Especially, the correct rate of etiology, incubation period, route of transmission, and acquired immunity was <40%. Through conditional logistic regression test, the factor significantly associated with awareness in case group was age (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.94-0.98). And the factors associated with awareness in control group were female (OR, 1.56; 95% CI, 1.03-2.36) age (OR, 0.98; 95% CI, 0.96-0.99), family history of scrub typhus (OR, 10.18; 95% CI, 1.37-75.99), history of receiving prevention education (OR, 8.47; 95% CI, 1.14-63.00). Conclusions: The rate of awareness was relatively low in study population. Thus, effective working guidelines and educational program to prevent scrub typhus must be developed, and publicity activities about the prevention of scrub typhus are needed for high-risk groups.

• Pediatric Infection and Vaccine
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• v.6 no.2
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• pp.245-252
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• 1999

Purpose : The aim of this study is to determine the age-specific seropositivity and the level of measles specific IgG in adults and to evaluate herd immunity to measles in Korea, the measles specific IgG were measured from the sera of adults over ages of 20 in Korea. Methods : 156 sera were collected from 156 out-patients over ages 20, who had visited clinical laboratory from June to July in 1997 at Korea University Ansan Hospital. The histories of natural measles or vaccination were not undertaken. Measles specific IgG titers were measured using ELISA method($SIA^{TM}$ Measles IgG Kit Co. St. Louis. Mo). Results : The results obtained from this study were as follows. 1) The seropositivity of measles specific IgG in adults was 94.9%. And there were no significant differences in their age and gender. 2) The mean measles-specific IgG titer was $238{\pm}84AU/mL$. And there were no significant differences in age and gender, except significant lower in 4th decades than other age groups. And there were no significant correlations between age and measles specific IgG level. Conclusion : In conclusion, a seropositivity of in adults was 94.9% which was higher than that of adolescents(91.2% in previous study), and antibody level was similar with adolescents. The herd immunity of the adults were considered to enough for protecting the transmission of measles in the community. For the eradication of measles in Korea, more efforts will be required to increase the vaccine coverage rate in children and adolescents.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.4 no.2
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• pp.191-198
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• 2001

Purpose: This study was undertaken to investigate the seroepidemiologic pattern of Helicobacter pylori (H. pylori) and hepatitis A virus (HAV) infections in children. Methods: A total of 315 serum samples were obtained from healthy children, living in Gwangju and Chonnam area. All serum samples were assayed for H. pylori IgG level using enzyme immunoassay techniques. HAV IgG level in serum were tested by a competitive radio-immunoassay in 215 subjects. The age-specific seroprevalence of H. pylori and HAV was separately analysed. The concordance of seropositivity and seronegativity between H. pylori and HAV infection was examined by the kappa statistic analysis. Results: Seropositivity was found in 17.5% (55/315) and 30.2% (65/215) of the subjects for H. pylori and HAV, respectively. Cross-tabulation of these data showed that 21 subjects (9.8%) were seropositive and 135 (62.8%) were seronegative for both H. pylori and HAV, 15 (7.0%) were seropositive for only H. pylori and 44 (20.5%) for only HAV. The seroprevalence of H. pylori and HAV increased significantly with age. There was a slight agreement between H. pylori and HAV seropositivity (${\kappa}$=0.26). Conclusion: This study shows a slight similarity in the concordance of seropositivity and seronegativity between H. pylori and HAV infection and provides evidence that H. pylori and HAV may share a common mode of transmission.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.174-175
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• 2012

(In, Ga) N-based III-nitride semiconductor materials have been viewed as the most promising materials for the applications of blue and green light emitting devices such as light-emitting diodes (LEDs) and laser diodes. Although the InGaN alloy can have wide range of visible wavelength by changing the In composition, it is very hard to grow high quality epilayers of In-rich InGaN because of the thermal instability as well as the large lattice and thermal mismatches. In order to avoid phase separation of InGaN, various kinds of structures of InGaN have been studied. If high-quality In-rich InGaN/GaN multiple quantum well (MQW) structures are available, it is expected to achieve highly efficient phosphor-free white LEDs. In this study, we proposed a novel InGaN double hetero-structure grown on GaN nano-pyramids to generate broad-band red-color emission with high quantum efficiency. In this work, we systematically studied the optical properties of the InGaN pyramid structures. The nano-sized hexagonal pyramid structures were grown on the n-type GaN template by metalorganic chemical vapor deposition. SiNx mask was formed on the n-type GaN template with uniformly patterned circle pattern by laser holography. GaN pyramid structures were selectively grown on the opening area of mask by lateral over-growth followed by growth of InGaN/GaN double hetero-structure. The bird's eye-view scanning electron microscope (SEM) image shows that uniform hexagonal pyramid structures are well arranged. We showed that the pyramid structures have high crystal quality and the thickness of InGaN is varied along the height of pyramids via transmission electron microscope. Because the InGaN/GaN double hetero-structure was grown on the nano-pyramid GaN and on the planar GaN, simultaneously, we investigated the comparative study of the optical properties. Photoluminescence (PL) spectra of nano-pyramid sample and planar sample measured at 10 K. Although the growth condition were exactly the same for two samples, the nano-pyramid sample have much lower energy emission centered at 615 nm, compared to 438 nm for planar sample. Moreover, nano-pyramid sample shows broad-band spectrum, which is originate from structural properties of nano-pyramid structure. To study thermal activation energy and potential fluctuation, we measured PL with changing temperature from 10 K to 300 K. We also measured PL with changing the excitation power from 48 ${\mu}W$ to 48 mW. We can discriminate the origin of the broad-band spectra from the defect-related yellow luminescence of GaN by carrying out PL excitation experiments. The nano-pyramid structure provided highly efficient broad-band red-color emission for the future applications of phosphor-free white LEDs.

• Journal of East-West Nursing Research
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• v.3 no.1
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• pp.50-67
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• 1998

When recognition of the Ghi(氣) which exist in all things, is changed on the aspects of the science of nursing, the view of health and nursing will be more efficient and can be developed as the proper concept for Korean culture. I think it is nessary to confirm which philosophical basis of the will be applicable to nursing and how to it has to be developed. Therefore I can for the research of the Ghi phenomena to attain the Thoughts of philosophy that is appropriate to expound those phenomena. And I attempt to induct "the fusion of horizons" to unify the view of the I world between Korea and the West. The Ghi is very energetic and omnipresent among the universe, Nature, and the human being. So it can organize all the primary elements of mental and I physical function of human as like life, mind, breath, feeling, energy, etc. A general concept of the Ghi is described as follows ; (1) The Ghi is the origin and essence to organize the universe, Nature, and the human being. (2) It is the perpetually movable thing. (3) And there are continuous transmission between the Ghi of the universe and the human through 'body, mind, and soul. For review on the philosophic basis of the Ghi, I studied out the identity of the doctrine of Li and Ch'i(理氣論) in the field of philosophy of Korea and the West. In Korea, the concept of the Vigor is based on Ch'i monolism(기일원론) and Li Ch'i dualism (이기이원론) of Yul-gok Lee's, Toi-kye Lee's, Hwa-dam's, and/or Hekang's. These are indispensable for the view of the world of Korea as Metaphysical ideology, Concrete science, Materialism, Ontology, and Epistemology. From the viewpoint of the philosophy of the West, the doctrine of Li and Ch'i(이기론) of Korea is identical with the doctrine of Li and Ch'i(이기론) of Joo-ja, Idea of Plato, Metaphysics of Aristotle, World Spirit(Weltgeist) of Hegel, and Existentialism of Heidegger. In the nursing theory of the West, some of them referred to the Ghi as like Energy field theory of Rogers and Energy exchange of Neuman. Though there are different in terminology, "energy" and the "Ghi" are induced comparable therapeutic action between the human and the environments. With the nursing theory of Korea, I have made an attempt to compare the Ghi with metaparadigm of nursing-the human being, the environment, the health, and the nursing. For the most part, the alternative therapy is resonable to the frame of the nursing theory of Korea. It is easy to apply alternative therapy on the every spot of nursing. So this therapy could be a kind of forms as nursing therapy in the nursing centers where take the duties of supporting in local societies. In result, independent nursing intervention will be activated by the nurse who puts up with the major parts. It is available to apply this therapy to palliation of pain, insomnia of infant, Sanhujori (산후조리), pain of menstruation, arthritis. And the alternative therapy makes it possible to propose the nursing model which represent originality, tradition, and history of the nursing of Korea. Additionally, in the field of the nursing, it is indispensable to choose a suitable methodology which is considered whether it is matched with a theory of philosophy in the boundary and object of the research. Because there are many way to get the knowledge of nursing related to the Ghi. In the science of nursing, context of sociocultural background and frame are required to understand the person who need to take care of (nursing client). But the value systems of the West and the East are distinctive each other as well as the behavior of health persuance. Therefore it is the basic research data of great worth to review philosophical the Ghi phenomena which is well known to Korean.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.79-84
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• 2017

The solar cells should be protected from the moisture and oxygen in order to sustain the properties and reliability of the devices. In this research, we prepared the protection films on the flexible plastic substrates by spray coating method using organic-inorganic hybrid solutions. The protection characteristics were studied depending on the various process conditions (nozzle distance, thicknesses of the coatings, film structures). The organic-inorganic solutions for the protection film layer were synthesized by addition of $Al_2O_3$ ($P.S+Al_2O_3$) and $SiO_2$ ($P.S+SiO_2$) nano-powders into PVA (polyvinyl alcohol) and SA (sodium alginate) (P.S) organic solution. The optical transmittances of the protection film with the thicknesses of $5{\mu}m$ showed 91%. The optical transmittance decreased from 81.6% to 73.6% with the film thickness increased from $78{\mu}m$ to $178{\mu}m$. In addition, the protective films were prepared on the PEN (polyethylene naphthalate), PC (polycarbonate) single plastic substrates as well as the Acrylate film coated on PC substrate (Acrylate film/PC double layer), and $Al_2O_3$ film coated on PEN substrate ($Al_2O_3$ film/PEN double layer) using the $P.S+Al_2O_3$ organic-inorganic hybrid solutions. The optimum protection film structure was studied by means of the measurements of water vapor transmittance rate (WVTR) and surface morphology. The protective film on PEN/$Al_2O_3$ double layer substrate showed the best water protective property, indicating the WVTR value of $0.004gm/m^2-day$.

• Journal of Ginseng Research
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• v.44 no.3
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• pp.442-452
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• 2020

Backgroud: Sleep deprivation (SD) impairs learning and memory by inhibiting hippocampal functioning at molecular and cellular levels. Abnormal autophagy and apoptosis are closely associated with neurodegeneration in the central nervous system. This study is aimed to explore the alleviative effect and the underlying molecular mechanism of stem-leaf saponins of Panax notoginseng (SLSP) on the abnormal neuronal autophagy and apoptosis in hippocampus of mice with impaired learning and memory induced by SD. Methods: Mouse spatial learning and memory were assessed by Morris water maze test. Neuronal morphological changes were observed by Nissl staining. Autophagosome formation was examined by transmission electron microscopy, immunofluorescent staining, acridine orange staining, and transient transfection of the tf-LC3 plasmid. Apoptotic event was analyzed by flow cytometry after PI/annexin V staining. The expression or activation of autophagy and apoptosis-related proteins were detected by Western blotting assay. Results: SLSP was shown to improve the spatial learning and memory of mice after SD for 48 h, accomanied with restrained excessive autophage and apoptosis, whereas enhanced activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway in hippocampal neurons. Meanwhile, it improved the aberrant autophagy and apoptosis induced by rapamycin and re-activated phosphoinositide 3-kinase/Akt/mammalian target of rapamycin signaling transduction in HT-22 cells, a hippocampal neuronal cell line. Conclusion: SLSP could alleviate cognitive impairment induced by SD, which was achieved probably through suppressing the abnormal autophagy and apoptosis of hippocampal neurons. The findings may contribute to the clinical application of SLSP in the prevention or therapy of neurological disorders associated with SD.