• The Korean Journal of Nuclear Medicine
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• v.30 no.3
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• pp.299-314
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• 1996

The purpose of the present study was to validate the use of tissue radioactivity ratios instead of regional metabolic rates for the assessment of regional metabolic changes in Alzheimer's disease(AD) with [$^{18}F$]FDG PET and to examine the correlation of ratio indices with the severity of cognitive impairment in AD. Thirty-seven AD Patients(age $68{\pm}9 yrs$, $mean{\pm}s.d.$; 36 probable and 1 definite AD), 28 patients with dementia of non-Alzheimer type(age $66{\pm}7 yrs$), and 17 healthy controls(age $66{\pm}4 yrs$) underwent [$^{18}F$]FDG PET imaging. Two simplified radioactivity ratio indices were calculated from 37-66 min image: region-to-cerebellar radioactivity ratio(RCR) and a composite radioactivity ratio(a ratio of radioactivity in the most typically affected regions over the least typically affected regions: CRR). Local cerebral metabolic rate for glucose(LCMRglu) was also measured using a three-compartment, five-parameter tracer kinetic model. The ratio indices were significantly lower in AD patients than in controls(RCR in temporoparietal cortex, $0.949{\pm}0.136$ vs. $1.238{\pm}0.129$, p=0.0004; RCR in frontal cortex, $1.027{\pm}0.128$ vs. $1.361{\pm}0.151$, p<0.0001; CRR, $0.886{\pm}0.096$ vs. $1.032{\pm}0.042$. p=0.0024). On the RCR analysis, 86% of AD patients showed a pattern of bilateral temporoparietal hypometabolism with or without frontal involvement; hypometabolism was unilateral in 11% of the patients. When bilateral temporoparietal hypometabolism was considered to be suggestive of AD, the sensitivity and specificity of the RCR analysis for the differential diagnosis of AD were 86% and 73%, respectively. The RCR was correlated significantly with the macroparameter K [$K_1k_3/(k_2+k_3)$] (r=0.775, p<0.0001) and LCMRglu(r=0.633, p=0.0002) measured using the kinetic model. In patients with AD, both average RCR of cortical association areas and CRR were correlated with Mini-Mental Status Examination(r=0.565, p=0.0145; r=0.642, p=0.0031, respectively), Clinical Dementia Rating(r=-0.576, p=0.0124; r=-0.591, p=0.0077), and total score of Mattis Dementia Rating Scale (r=0.574, p=0.0648; r=0.737, p=0.0096). There were also significant correlations between memory and language impairments and corresponding regional RCRs. The results suggest that the [$^{18}F$]FDG PET ratio indices, RCR and CRR, reflect global and regional metabolic rates and correlate with the severity of cognitive impairment in AD. The simplified ratio analysis may be clinically useful for the differential diagnosis and serial monitoring of the disease.

• Pediatric Infection and Vaccine
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• v.7 no.1
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• pp.143-151
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• 2000

Purpose : The accuracy of bacteriologic diagnosis of beta-hemolytic streptococcal pharyngotonsillitis depends on the degree of carrier rate in that area where the throat swabs are obtained and the evaluation of serological T typing as an epidemiologic marker is important to understand epidemiology of streptococcal infection. The purpose of this study is to know the carrier rates of group A streptococcus in normal children form four different areas and to find out the epidemiologic characteristic in distribution of the serotypes for 3 years. Method : Throat swabs were obtained from the tonsillar fossa of normal school children in four different areas(Uljin, Seoul, Osan, Kunsan) from March to May 1996, in Uljin in April 1997, and in Uljin in April 1998. The samples were plated on a 5% sheep blood agar plate and incubated overnight at $37^{\circ}C$ before examination for the presence of beta-hemolytic colonies. All isolated beta-hemolytic streptococcus were grouped and serotyped by T agglutination. Results : The carrier rate of beta-hemolytic streptococci and group A streptococci in 1996 were 27.6%, 18.6% at Uljin; 16.4%, 2.7% at Seoul; 33.0%, 26.0% at Osan; 20.0%, 12.3% at Kunsan, respectively. Among 1,192 normal school children from 4 different areas, we obtained 179 strains of group A streptococci. Fifty two percent of the strains were typable by T agglutination in 1996. Common T-type in 1996 were NT, T1, T3, T2 at Uljin; T12, T25 at Seoul; NT, T6, T28 at Osan; T25, T4, NT, T5 at Kunsan, in decreasing order, respectively. At Uljin, T1, T3, T25 accounted for 69% of strains in 1996, T1, T12, T25 accounted for 70% in 1997, and T12, T4 accounted for 88% in 1998. Conclusion : Higher carrier rates were found in Uljin and Osan, where there are a lower population density with scanty of medical facilities compared with another areas. We supposed that low carrier rates is likely to be related to antibiotic abuse or some epidemiologic factor. The periodic and seasonal serotyping analysis is important in monitoring and understanding the epidemiologic patterns of group A streptococci.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.4
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• pp.301-311
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• 2011

Introduction: This study examined the effect of the application of low intensity pulsed ultrasound on bone healing after an injection of adipose tissue-derived stem cells (ADSCs) during the implantation of a titanium implant in the tibia of diabetes-induced rats. Materials and Methods: Twelve Sprague-Dawely rats were used. After inducing diabetes, the ADSCs were injected into the hole for the implant. Customized screw type implants, 2.0 mm in diameter and 3.5 mm in length, were implanted in both the tibia of the diabetes-induced rats. After implantation, LIPUS was applied with parameters of 3 MHz, 40 mW/$cm^2$, and 10 minutes for 7 days to the left tibiae (experimental group) of the diabetesinduced rats. The right tibiae in each rat were used in the control group. At 1, 2 and 4 week rats were sacrificed, and the bone tissues of both tibia were harvested. The bone tissues of the three rats in each week were used for bone-to-implant contact (BIC) and bone area (BA) analyses and the bone tissues of one rat were used to make sagittal serial sections. Results: In histomorphometric analyses, the BIC in the experimental and control group were respectively, $39.00{\pm}18.17%$ and $42.87{\pm}9.27%$ at 1 week, $43.74{\pm}6.83%$ and $32.27{\pm}6.00%$ at 2 weeks, and $32.62{\pm}11.02%$ and $47.10{\pm}9.77%$ at 4 weeks. The BA in experimental and control group were respectively, $37.28{\pm}3.68%$ and $31.90{\pm}2.84%$ at 1 week, $20.62{\pm}2.47%$ and $15.64{\pm}2.69%$ at 2 weeks, and $11.37{\pm}4.54%$ and $17.69{\pm}8.77%$ at 4 weeks. In immunohistochemistry analyses, Osteoprotegerin expression was strong at 1 and 2 weeks in the experimental group than the control group. Receptor activator of nuclear factor kB ligand expression showed similar staining at each week in the experimental and control group. Conclusion: These results suggest that the application of low intensity pulsed ultrasound after an injection of adipose tissue-derived stem cells during the implantation of titanium implants in the tibia of diabetes-induced rats provided some positive effect on bone regeneration at the early stage after implantation. On the other hand, this method is unable to increase the level of osseointegration and bone regeneration of the implant in an uncontrolled diabetic patient.

• Cross-Cultural Studies
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• v.50
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• pp.31-51
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• 2018

The concept of 'monsters' have become popular, again, in recent times. A number of 'monster narratives' that discuss monsters such as zombies, humanoids, viruses, extraterrestrials, and serial killers have been made and re-made in popular media. Noting such an interesting cultural context, this article attempts, first, to find out some essential prototypical elements of a monster narrative and, second, to relate it with a catastrophic narrative. Correspondingly, the word 'monster' has been used as a conceptual prototype category that denies universal and clear definition, which makes it as one of the most widely used and familiar subjects of the use of metaphor. The prototypical meanings of various monster figures can be converged on a certain creature of being in this way held out as bizarre, curious, and abnormal. The monster figure that surpasses existing normality is also connected to 'abjection,' such as something that is cast aside from the body such as the bodily functions seen in its associated blood, tears, vomit, excrement, or semen, and so on. Nevertheless, both the monster figure and abjection produce disgust and horror in the minds of ordinary spectators or readers of media using this metaphor to heighten excitement for the viewers. The abject characteristic of the monster figure also has something in common with the posthuman figure, meaning to apply to a category of inhuman others who are held outside of the normal category of human beings. In the similar vein, it is natural that the most typical monster figures in our times are posthuman creatures embodied in such forms as seen with zombies, humanoids, cyborgs, robots, and so on. In short, the monster figure includes all of the creatures and beings that disarray normalized humanist categories and values. The monster narrative, in the same sense, is a type of story that tells about others outside modern, anthropocentric, male-centered, and Westernized categories of thought. It can be argued that a catastrophic narrative, a literary genre which depicts the world where a series of catastrophic events demolish the existing human civilization, ought to be seen as a typical modern-day monster narrative, because it also discounts and criticizes normalized humanist categories and values as is the result of the monster narrative. Going beyond the prevailing humanist realist narrative that are so familiar with existing values, the catastrophic narrative is not only a monster narrative per se, but also a monstrous narrative which disrupts and reinvents currently mainstream narratives and ways of thinking.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.100-108
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• 2012

The purpose of the study was to evaluate the influence of shading and ventilation on Mean Radiant Temperature(MRT) of the outdoor space at a summer outdoor. The Wind Speed(WS), Air Temperature(AT) and Globe Temperature(GT) were recorded every minute from $1^{st}$ of May to the $30^{th}$ of September 2011 at a height of 1.2m above in four experimental plots with different shading and ventilating conditions, with a measuring system consisting of a vane type anemometer(Barini Design's BDTH), Resistance Temperature Detector(RTD, Pt-100), standard black globe(${\O}$ 150mm) and data acquisition systems(National Instrument's Labview and Compfile Techs' Moacon). To implement four different ventilating and shading conditions, three hexahedral steel frames, and one natural plot were established in the open grass field. Two of the steel frames had a dimension of $3m(W){\times}3m(L){\times}1.5m(H)$ and every vertical side covered with transparent polyethylene film to prevent lateral ventilation(Ventilation Blocking Plot: VP), and an additional shading curtain was applied on the top side of a frame(Shading and Ventilation Blocking Plot: SVP). The third was $1.5m(W){\times}1.5m(L){\times}1.5m(H)$, only the top side of which was covered by the shading curtain without the lateral film(Shading Plot: SP). The last plot was natural condition without any kind of shading and wind blocking material(Natural Open Plot: NP). Based on the 13,262 records of 44 sunny days, the time serial difference of AT and GT for 24 hour were analyzed and compared, and statistical analysis was done based on the 7,172 records of daytime period from 7 A.M. to 8 P.M., while the relation between the MRT and solar radiation and wind speed was analyzed based on the records of the hottest period from 11 A.M. to 4 P.M.. The major findings were as follows: 1. The peak AT was $40.8^{\circ}C$ at VP and $35.6^{\circ}C$ at SP showing the difference about $5^{\circ}C$, but the difference of average AT was very small within${\pm}1^{\circ}C$. 2. The difference of the peak GT was $12^{\circ}C$ showing $52.5^{\circ}C$ at VP and $40.6^{\circ}C$ at SP, while the gap of average GT between the two plots was $6^{\circ}C$. Comparing all four plots including NP and SVP, it can be said that the shading decrease $6^{\circ}C$ GT while the wind blocking increase $3^{\circ}C$ GT. 3. According to the calculated MRT, the shading has a cooling effect in reducing a maximum of $13^{\circ}C$ and average $9^{\circ}C$ MRT, while the wind blocking has heating effect of increasing average $3^{\circ}C$ MRT. In other words, the MRT of the shaded area with natural ventilation could be cooler than the wind blocking the sunny site to about $16^{\circ}C$ MRT maximum. 4. The regression and correlation tests showed that the shading is more important than the ventilation in reducing the MRT, while both of them do an important role in improving the outdoor thermal comfort. In summary, the results of this study showed that the shade is the first and the ventilation is the second important factor in terms of improving outdoor thermal comfort in summer daylight hours. Therefore, it can be apparently said that the more shade by the forest, shading trees etc., the more effective in conditioning the microclimate of an outdoor space reducing the useless or even harmful heat energy for human activities. Furthermore, the delicately designed wind corridor or outdoor ventilation system can improve even the thermal environment of urban area.