• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.39-48
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• 2010

Recreation forests are in the spotlight as the place for personality development, mind and body comfort, companionship, and environment education in forests and valleys. Visitors to recreation forests have been on the increase along with booming in recreation forest building since 1988. Recreation forests are being categorized according to some features such as regional and environmental condition. Recreation forests, however, have not met the expectations of some visitors who want to take a rest with calmness due to the influence of the 5-day-work-week system, increasing interest in rest, leisure, and well-being, and users converge during weekends, summer, and the tourist season. In order to improve visitors' satisfaction efficiently, this study surveyed the level of satisfaction in each cluster based on the precedent study which had classified 85 national or public recreation forests in Korea into clusters. Questionnaires were distributed properly to each cluster and, of the 1,132 questionnaires collected, 1,015 were valid and used for analysis. Reliability of questionnaires and statistical validity of the model were verified. As a result, there are meaningful differences in the ranking of independent variables which affect the level of satisfaction according to clusters. Variables in rest and fatigue recovery have the strongest influence on the level of satisfaction in the clusters of potential factor, internal activation factor, and mixed potential capacity factor. In the use performance and visiting condition factor cluster, appropriateness of visit cost is most influential and, in the education cluster, connectivity with tourist attractions around it is most affective. These results can provide priority in services and maintenance of recreation forests for improving the level of satisfaction and differentiate the distribution of resources according to clusters.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.13-23
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• 2010

Objective: The present study was carried out to induce differentiation of human embryonic stem cells (hESCs) into germ cells and to establish a culture condition for single hESCs dissociated by enzyme. Methods: Embryonic body (EB) was formed by hanging drop culture for 3 days from hESCs colony. The EBs were cultured in the medium supplemented with retionic acid (RA) or/and bone morphogenetic protein-4 (BMP4) for 14 days to differentiate into germ cells. Germ cell specific markers, c-kit and VASA were used for immunohistochemistry of EB. Human ESCs colonies were dissociated into single cells by Collagenase, Tryple and Accutase, and then colony formation rate of the single cells was examined. Rho-associated kinase inhibitor (ROCK inhibitor, Y27632) was added into the culture medium of single cells to reduce the apoptotic damage during the dissociation. Results: Single cells dissociated with Tryple or Accutase showed higher colony formation rates compared to the cells dissociated with Collagenase. Seeding of $5{\times}10^3$ cells/well (4 well dish) was efficient to obtain high colony formation rate compared to other concentrations of seeding cell. Addition of Y27632 significantly increased the colony formation rate of the single cells dissociated by Tryple. Immunohistochemistry of EB with c-kit and VASA markers showed a weak fluorescence signals compared to the signals from the testicular tissue. Conclusion: Dissociation with Tryple was useful to obtain healthy single cells and addition of Y27632 was beneficial for survival and colony formation of the single cells. Unlike other studies, we just observed a dim fluorescence staining of the germ cell markers, probably caused by the short-term culture for the differentiation of EB compared to other studies.

• Journal of Oral Medicine and Pain
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• v.30 no.1
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• pp.45-55
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• 2005

As people prefer to use right or left hand, some have preferred chewing side while others do not. Totally, 82 volunteers composed of students and staffs from Dental Hospital College of Dentistry Yonsei University participated in this study for the investigation of influence of preferred chewing habit, that has lasted for more than a year, on electromyographic(EMG) activity of masticatory muscles and bite force. Among the 82 volunteers, 46 had preferred chewing habit while the other 36 did not. Prior to the investigation, those with factors that could affect the study, such as, general disease, irregular dentition and malocclusion, were screened and excluded by questionnaire and clinical examination. The results were as follows: 1. There was no significant difference in EMG activities between chewing side and non-chewing side of preferred chewing subjects at rest as well as maximal voluntary contraction(MCV)(p>0.05). 2. Asymmetrical coefficient of temporal and masseter muscle EMG activities between preferred chewing subjects and non-preferred chewing subjects at rest was not significantly different(p>0.05). 3. Asymmetrical coefficient of masseter EMG activity was significantly higher(p<0.05) than that of non-preferred chewing subjects at MCV, whereas that of anterior temporal muscle showed no difference(p<0.05). 4. In preferred chewing subjects, there was no significant difference in average bite force and occlusal contact area between chewing side and non-chewing side(p>0.05). 5. There was no significant difference in Asymmetrical coefficients of average bite force and occlusal contact area between preferred chewing subjects and non-preferred chewing subjects (p>0.05). Consequently, preferred chewing habit can be considered as physiological asymmetry with normal function rather than to have influence on EMG muscle activity of masticatory muscles, average bite force and occlusal contact area. Objective standardization to differentiate preferred chewing subjects and non-preferred chewing subjects should be established in the further study.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.311-321
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• 1998

Background: Mucoepidermoid carcinoma of the lung arises from submucosal gland of tracheobronchial tree. Histologically, the tumor is composed of mucin-secreting cells, squamous cells, and intermediated cells, which show no particular differentiating characteristics, in varying proportions. The tumor is divided into low grade and high grade depending on the proportion of cells, and the degree of the mitotic activity, cellular necrosis and nuclear pleomorphism. While favorable prognosis of low grade tumor, high grade tumor, which is very difficult to differentiate from adenosquamous carcinoma, has an aggressive clinical course. The tumor is rare, comprising 0.1 to 0.2% of primary lung cancers and 1 to 5% of bronchial adenomas. Method: A retrospective clinical study was done on 17 cases of mucoepidermoid carcinoma. The study investigated the clinical features, radiologic findings, bronchoscopic findings, histology and clinical courses. Results: Age ranged between second to seventh decade with a mean age of 42 years. Twelve out of 17 cases were male. Five out of 17 cases were smokers with a mean 11 pack-years. Common symptoms included dyspnea, cough, hemoptysis, and wheezing. Two out of 17 cases was asymptomatic. Atelectasis or mass was common radiologic finding. Plain chest radiography was normal in one patient whom the tumor was located in upper trachea. Bonchoscopy revealed exophytic mass in 12 cases and nodular infiltrations in 4 cases. One case having solitary pulmonary nodule in the right lower lung was normal on bronchoscopy. Histologically, ten out of 17 cases were low grade, and seven out of 17 cases were high grade. Among 10 patients with low grade tumor,9 patients were performed operation and have been alive without recurrence during a mean follow-up of 30 months. Two out of 7 patients with high grade tumor were performed pneumonectomy and have been alive during a follow-up of 3 and 8 months, respectively. Conclusion: Most of mucoepidermoid carcinoma is located at central airway and is presented symptoms by mucosal irirtation. Although atelectasis or mass is common radiologic finding. chest X -ray can be normal. The histologic grading and the extent of tumor are two most important factors for prognosis.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.280-289
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• 1998

Background: It is sometimes difficult to differentiate tuberculous pleural effusion from malignant pleural effusion by clinical symptoms, signs, by routine tests of pleural fluid, and by pathologic studies. And recently, it was discovered that cytokines such as IL-2, IFN-$\gamma$, TNF-$\alpha$ are elevated in tuberculous pleural fluid, and there have been several attempts to diagnose tuberculous pleural effusion by using these immunological mediators. There are several studies regarding the diagnostic value of IFN-$\gamma$, and there are two studies in Korea. But the diagnostic values of IFN-$\gamma$ in these studies were slightly lower than those in other countries. To compare the diagnostic value of IFN-$\gamma$ with those of CEA and ADA, and to determine the sensitivity and specificity of IFN-$\gamma$ in Korean, we mesured IFN-$\gamma$, CEA level and ADA activity in pleural effusions. Methods: ADA activity, IFN-$\gamma$ level and CEA level as well as cell count, differential count, and biochemical assays such as protein content and lactate dehydrogenase were measured in 40 cases of tuberculous pleuritis and 42 cases of malignant pleural effusion. Results: Tuberculous pleural fluid showed higher levels of IFN-$\gamma$ and ADA ($832.6{\pm}357.2$ pg/ml and $82.5{\pm}25.9$ U/L, respectively) than those of malignant pleural effusion ($2.6{\pm}8.0$ pg/ml and $19.2{\pm}10.9$ U/L, respectively) (p<0.01). Malignant pleural effusions showed higher median value (102.2 ng/ml) than tubercalous pleural effusions (1.8 ng/ml) (p<0.01). The sensitivities of IFN-$\gamma$, ADA, CEA were 0.97, 0.87, 0.67 and the specificities of IFN-$\gamma$, ADA, CEA were 1.0, 0.97, 1.0, respectively. There was no significant correlation between ADA activity and IFN-$\gamma$ level. Conclusion: This study showed that IFN-$\gamma$ test would be a very useful clinical test for differential diagnosis of tuberculous pleuritis and malignant pleural effusion because it is very sensitive and specific, although it is an expensive test.

• Tuberculosis and Respiratory Diseases
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• v.61 no.1
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• pp.20-25
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• 2006

Background: Although fever is one of the most common and challenging problem in intensive care medicine(ICU), it is difficult to distinguish between infectious and non-infectious causes. Procalcitonin(PCT) has recently been reported to be an indicator of various infectious diseases. This study examined whether or not measuring the serum PCT level in patients with fever in the ICU can help distinguish fevers with infectious causes from those with non-infectious causes. Methods: ICU patients with fever at $38^{\circ}C$ or over from March to August 2005 were prospectively enrolled. The cause of the fever was identified by the culture results and clinical course. The leukocytes, CRP, PCT, IL-6, and $TNF-{\alpha}$ in the fever patients with infectious and non-infectious causes were compared, and the PCT level in the patients with fever in the ICU were compared with those without fever. Results: 1) 42 patients were enrolled and 46 cases of fever were analyzed. 26 cases were considered to be infectious, while 13 cases were considered to be non-infectious. 7 cases were found to have no clear causes. 2) There were no significant differences in the degree of fever, leukocytes count, CRP, IL-6, and $TNF-{\alpha}$ levels in the patiemts with infectious and non-infectious causes. 3) The serum PCT level was higher in those with infectious causes than in those with non-infectious causes ($15.1{\pm}32.57ng/mL$ vs $2.68{\pm}3.63ng/mL$) but there was no statistical significance (p=0.06). 4) The serum PCT level of the ICU patients with fever was significantly higher than in those without fever ($10.94{\pm}27.15ng/mL$ vs $0.45{\pm}0.49ng/mL$) (p=0.02). Conclusion: The serum PCT cannot be used to distinguish the fever in ICU patients with infectious causes from that with non-infectious causes.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.4
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• pp.239-252
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• 2007

Objectives: In the present study, we examined the differentiation potential of human adipose-(HAD) and human umbilical cord-derived mesenchymal like stem cells (HUC) into cardiomyocytes. Methods: Cells were initially exposed to 5-azacytidine for 24h cells and then were cultivated in the presence or absence of activin A, TGF-$\beta$1, or Wnt inhibitor with various combinations of BMP and FGF. Assessment of cardiomyogenic differentiation was made upon the expression of cardiomyocyte-specific genes using RT-PCR. Results: HAD that cultivated in control medium for 4 weeks after 5-azacytidine expose showed new expression of TnT gene and increased expression of Cmlc1 and kv4.3 genes. However, HAD cultivated in the presence of combinations of BMP-4/FGF-4 (B4/F4) and BMP-4/FGF-8 (B4/F8) showed new expression of $\beta$-MHC gene and more increased expression of Cmlc1, TnT, TnI, Kv4.3 genes. Significantly enhanced expression of Cmlc1, TnT, and Kv4.3 genes were also observed compared to that cultivated in the control medium. Treatment of HUC with either 5-azacytidine or combinations of BMP and FGF did not affect the expression profile of these genes. However, when activin A or TGF-$\beta$1 was present in addition to the BMP-2/FGF-8 (B2/F8) after 5-azacytidine exposure, HUC exhibited new expression of $\beta$-MHC gene and increased expression of $\alpha$-CA, TnT and Kv4.3 genes. When Wnt inhibitor was present in addition to BMP and FGF, HUC showed new expression of Cmlc1 gene and increased expression of $\alpha$-CA, TnT, TnI and Kv4.3 genes. Conclusions: Based on these observations, it is suggested that HAD and HUC could differentiate into cardiomyocytes which might be used as therapeutic cells for the heart diseases.

• Tuberculosis and Respiratory Diseases
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• v.56 no.3
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• pp.268-279
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• 2004

Background : The tuberculin skin test has been used to diagnose latent tuberculosis infection, but is not widely used to diagnose or exclude pulmonary tuberculosis. The objective of this study was to evaluate the diagnostic utility of the tuberculin test in diagnosing and excluding pulmonary tuberculosis, and differentiating pulmonary tuberculosis from nontuberculous mycobacteria (NTM) pulmonary disease, when a sputum acid-fast bacilli (AFB) smear was positive. Material and Methods : From October 2002 to August 2003, among all the inpatients of the Division of Pulmonary and Critical Care Medicine at Samsung Medical Center, 258 patients with clinical suspicion of pulmonary tuberculosis were enrolled and underwent a tuberculin test. Results : 156 males and 102 females were included, with a mean age of 57.5 years. The final diagnoses included lung cancer in 89 cases (34.5%), pulmonary tuberculosis in 59 cases (22.9%), bacterial pneumonia in 33 cases (12.8%) and NTM pulmonary disease in 24 cases (9.3%). The positive tuberculin test rate was higher in the tuberculosis than non-tuberculosis group; 81.4 (48/59) vs. 42.4% (81/199). (p<0.001). In 208 patients with a negative sputum AFB smear, the result of the tuberculin test was positive in 69.4% (25/36) of the tuberculosis group and in 44.8% (77/172) of the non-tuberculosis group (p=0.007), so a positive result of the tuberculin test could predict pulmonary tuberculosis with 69.4% sensitivity, 55.2% specificity, a 24.5% positive predictive value and a 89.6% negative predictive value. In 50 patients with a positive sputum AFB smear, the positive rates of the tuberculin test were 83.9% (26/31) in tuberculosis group and 21.1% (4/19) in NTM pulmonary disease group (p<0.001), so a positive result of the tuberculin skin test could predict pulmonary tuberculosis with 83.9% sensitivity, 78.9% specificity, a 86.7% positive predictive value and a 75.0% negative predictive value. Conclusion : The tuberculin test could be useful in excluding pulmonary tuberculosis when the sputum AFB smear is negative, and to differentiate pulmonary tuberculosis from NTM pulmonary disease when the sputum AFB smear is positive.

• The Korean Journal of Nuclear Medicine
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• v.33 no.2
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• pp.111-119
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• 1999

Purpose: As mesial temporal lobe epilepsy (TLE) shows hypometabolism of medial and lateral temporal lobe, we investigated whether symmetric uptake of F-18-FDG in medial temporal lobes can differentiate mesial from lateral TLE. Materials and Methods: In 113 patients (83 mesial TLE, 30 lateral TLE) who underwent anterior temporal lobectomy and/or corticectomy with good surgical outcome, we performed F-18-FDG PET and compared F-18-FDG uptake of medial and lateral temporal lobes. All the patients with mesial TLE had hippocampal sclerosis except one congenital abnormal hippocampus. Patients with lateral TLE revealed cerebromalacia, microdysgenesis, arteriovenous malformation, old contusion, and cortical dysplasia. Results: Sensitivity of F-18-FDG PET and MR for mesial TLE was 84% (70/83) and 73% (61/83), respectively. Sensitivity of F-18-FDG PET and MR for lateral TLE was 90% (27/30) and 66% (20/30), respectively. Twelve patients were normal on F-18-FDG PET. 101 patients had hypometabotism of lateral temporal lobe. Among 88 patients who showed hypometabolism of medial temporal lobe as well as lateral temporal lobe, 70 were mesial TLE patients and 18 were lateral TLE on pathologic examination. Positive predictive value of medial temporal hypometabolism for mesial TLE was 80%. Among 13 patients who showed hypometabolism of only lateral temporal lobe, 4 were mesial TLE and 9 were lateral TLE. Positive predictive value of hypometabolism of lateral temporal lobe for the diagnosis of lateral TLE was 69% (9/13). Normal MR findings stood against medial TLE, whose negative predictive value was 66%. Conclusion: Lateral temporal lobe epilepsy should be suspected when there is decreased F-18-FDG uptake in lateral temporal lobe with normal uptake in medial temporal lobe.

• Journal of Intelligence and Information Systems
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• v.20 no.3
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• pp.1-18
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• 2014

Over the past years RFID/SN has been an elementary technology in a diversity of applications for the ubiquitous environments, especially for Internet of Things. However, one of obstacles for widespread deployment of RFID technology is the inherent unreliability of the RFID data streams by tag readers. In particular, the problem of false readings such as lost readings and mistaken readings needs to be treated by RFID middleware systems because false readings ultimately degrade the quality of application services due to the dirty data delivered by middleware systems. As a result, for the higher quality of services, an RFID middleware system is responsible for intelligently dealing with false readings for the delivery of clean data to the applications in accordance with the tag reading environment. One of popular techniques used to compensate false readings is a sliding window filter. In a sliding window scheme, it is evident that determining optimal window size intelligently is a nontrivial important task in RFID middleware systems in order to reduce false readings, especially in mobile environments. In this paper, for the purpose of reducing false readings by intelligent window adaption, we propose a new adaptive RFID data cleaning scheme based on window sliding for a single tag. Unlike previous works based on a binomial sampling model, we introduce the weight averaging. Our insight starts from the need to differentiate the past readings and the current readings, since the more recent readings may indicate the more accurate tag transitions. Owing to weight averaging, our scheme is expected to dynamically adapt the window size in an efficient manner even for non-homogeneous reading patterns in mobile environments. In addition, we analyze reading patterns in the window and effects of decreased window so that a more accurate and efficient decision on window adaption can be made. With our scheme, we can expect to obtain the ultimate goal that RFID middleware systems can provide applications with more clean data so that they can ensure high quality of intended services.