• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.4
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• pp.805-812
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• 2009

In many intrusion detection applications, n-gram approach has been widely applied. However, n-gram approach has shown a few problems including unscalability and double counting of features. To address those problems, we applied n-gram augmented Naive Bayes with k-truncated suffix tree (k-TST) storage mechanism directly to classify intrusive sequences and compared performance with those of Naive Bayes and Support Vector Machines (SVM) with n-gram features by the experiments on host-based intrusion detection benchmark data sets. Experimental results on the University of New Mexico (UNM) benchmark data sets show that the n-gram augmented method, which solves the problem of independence violation that happens when n-gram features are directly applied to Naive Bayes (i.e. Naive Bayes with n-gram features), yields intrusion detectors with higher accuracy than those from Naive Bayes with n-gram features and shows comparable accuracy to those from SVM with n-gram features. For the scalable and efficient counting of n-gram features, we use k-truncated suffix tree mechanism for storing n-gram features. With the k-truncated suffix tree storage mechanism, we tested the performance of the classifiers up to 20-gram, which illustrates the scalability and accuracy of n-gram augmented Naive Bayes with k-truncated suffix tree storage mechanism.

• Biomedical Science Letters
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• v.16 no.2
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• pp.75-82
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• 2010

The molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus (MRSA) isolates have demonstrated their genetic diversity and evolution. A total of 137 strains of MRSA clinical isolates was collected from Korean healthcare facility in 2007. The MRSA clinical isolates were analyzed by molecular typings (SCCmec element and agr locus typing), virule nce factor gene detections {(Panton-Valentine leukocidin (PVL), enterotoxin, exfoliative toxin and toxic shock syndrome toxin-1), and amplified fragment length polymorphism (AFLP)}. The MRSA clinical isolates were classified as SCCmec type II-agr type 1 (2 strains), type II-agr type 2 (79 strains), type III-agr type 1 (24 strains), type III-agr type 2 (2 strains), type IV-agr type 1 (27 strains), type IV-agr type 2 (2 strains), and non-typable (1 strain, agr type 3). Based on SCCmec types, SCCmec type II (95.1%) and III (88.5%) indicated higher multidrug resistance rate than SCCmec type IV (10.3%) (P<0.001). The most common enterotoxin genes were seg (83.8%), sei (83.1%), and sec (80.2%). The tst gene was present in 86 out of 137 (62.8%) MRSA isolates. All MRSA isolates were negative for PVL and exfoliative toxin genes. The combinations of toxin genes were observed in particular SCCmec types; 97.6% of SCCmec type II strains carried sec, seg, sei and tst genes, 73.0% of SCCmec type III strains carried sea gene, and 89.7% of SCCmec type IV strains carried sec, seg and sei genes. Each of the SCCmec types of MRSA isolates had distinct AFLP profile. In conclusion, SCCmec type II, agr type 1 and 2 have demonstrated to be the most common types in Korea, and the results indicated that the virulence factors are closely associated with their molecular types (SCCmec and agr types).

• Tuberculosis and Respiratory Diseases
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• v.82 no.4
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• pp.306-310
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• 2019

Background: Tuberculosis (TB) is increasing in immigrants. We aimed to investigate the current status of latent tuberculosis infection (LTBI) treatment for North Korean Refugees (NKR) compared to South Koreans Contacts (SKC). Methods: TB close contacts in a closed facility of SKC and NKR who underwent LTBI screening in a settlement support center for NKR were analyzed retrospectively. Results: Among tuberculin skin test (TST) ${\geq}10mm$ (n=298) reactors, the males accounted for 72.2% in SKC (n=126) and 19.5% in NKR (n=172) (p<0.01). The mean age was higher in South Korea ($42.8{\pm}9.9years$ vs. $35.4{\pm}10.0years$, p<0.01). Additionally, the mean TST size was significantly bigger in NKR ($17.39{\pm}3.9mm$ vs. $16.57{\pm}4.2mm$, p=0.03). The LTBI treatments were initiated for all screened NKR, and LTBI completion rate was only 68.0%. However, in NKR, LTBI treatment completion rate was significantly increased by shorter 4R regimen (odds ratio [OR], 9.296; 95% confidence interval [CI], 4.159-20.774; p<0.01) and male (OR, 3.447; 95% CI, 1.191-9.974; p=0.02). Conclusion: LTBI treatment compliance must be improved in NKR with a shorter regimen. In addition, a larger study regarding a focus on LTBI with easy access to related data for NKR should be conducted.

• Journal of Sleep Medicine
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• v.15 no.2
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• pp.37-42
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• 2018

Objectives: To assess the effect and safety of transcranial direct-current stimulation (tDCS) in primary chronic insomnia. Methods: A one-month, double-blind, randomized, sham-controlled trial was performed. A total of 7 patients with primary chronic insomnia received tDCS using anodal (n=3), cathodal (n=2), or sham stimulation (n=2). They were followed up at 1 week and 1 month after treatment. The primary outcome measures included improvement in total sleep time (TST), sleep latency (SL), and sleep efficiency (SE) at 1 month follow-up. Results: TST and SE were improved with tDCS at 1 month follow-up in all patients (100%) of the anodal group, one (50%) of the cathodal group, and one (50%) of the sham group. tDCS improved SL at 1 month follow-up in two patients (67%) of the anodal group, one (50%) of the cathodal group, and none (0%) of the sham group. With respect to adverse events, transient itching sensation occurred in one patient of the anodal group. None of the other groups reported adverse events. Conclusions: Our results suggest that tDCS may be effective and safe for treatment of primary chronic insomnia. A larger controlled study needs to be further investigated.

• Korean journal of aerospace and environmental medicine
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• v.31 no.3
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• pp.77-81
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• 2021

Purpose: The United States of America have pre-migration screening program are mandated through legislation. The one of purpose of this program is to prevent the importation of certain communicable diseases. Examinations of migration applicants are performed by panel physicians who are licensed physicians in the countries of origin that have agreements with the government departments of the country of destination to undertake this activity. In recent decades, the number of US migrants has increased, however COVID-19 impacted this trend of international migrants. The Aim of this study is to examine trends of US applicants and outcomes of tuberculosis and sexual transmitted infections (STIs) screening in South Korean applicants for US visa. Methods: A total of 4,442 applicants participated in US visa health check-up in 2016 to 2020. Results: The numbers of applicant for US visa in males and females was 1,814 and 2,628. The positive results in tuberculosis and STIs screening was noted with 0.66% in nontuberculous mycobacteria (NTM), 0.03% in tuberculosis, 0.03% in gonorrhea, 0.08% in syphilis, and 0.74% in chlamydia. The age groups of 2 to 14 years showed higher positive rate (13.89%) in tuberculin skin test (TST) tests compared to the rate of interferon gamma release assay (IGRA) tests (0.44%, P<0.001). The positive ratio of NTM and abnormal chest X-ray (CXR) which required sputum tests among the applicants over 15 years old has trends to increase with age. The age groups of over 70 years showed high positive rate in NTM and abnormal CXR (4.10%, 20.51%). However, ages 15 to 49 years groups showed 0.00% to 0.30% in NTM and 1.08% to 3.91% in abnormal CXR. In the study population, the positive rates of STIs were 0.03%, 0.08%, and 0.74% in gonorrhea, syphilis, and chlamydia, respectively. Among the participants who underwent sputum smears and cultures were just 1 case of active tuberculosis (0.03%) and 25 cases of NTM infection (0.66%). Conclusion: This study found that rate of positivity in tuberculosis and STIs screening among South Korean applicants for US visa in 2016 to 2020. Regarding tuberculosis, the positivity of CXR among the aged 15 to 59 years applicants was lower than that among over 60 years old. Among 2 to 14 years, positivity of IGRA was very low. And IGRA test can reduce effort of further evaluation compared to TST test in South Korea, so IGRA test among young adults can be useful. High positive rates in STI among young adult could result in high active sexuality, especially chlamydia infection is most common. Therefore Chlamydia polymerase chain reaction should be considered formal protocol among the Korean applicant for US visa.

• Journal of Ginseng Research
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• v.46 no.5
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• pp.666-674
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• 2022

Background: Ginsenosides and their metabolites have antidepressant-like effects, but the underlying mechanisms remain unclear. We previously identified 14-3-3 ζ as one of the target proteins of 20 (S)-protopanaxadiol (PPD), a fully deglycosylated ginsenoside metabolite. Methods: Corticosterone (CORT) was administered repeatedly to induce the depression model, and PPD was given concurrently. The tail suspension test (TST) and the forced swimming test (FST) were used for behavioral evaluation. All mice were sacrificed. Golgi-cox staining, GSK 3β activity assay, and Western blot analysis were performed. In vitro, the kinetic binding analysis with the Biolayer Interferometry (BLI) was used to determine the molecular interactions. Results: TST and FST both revealed that PPD reversed CORT-induced behavioral deficits. PPD also ameliorated the CORT-induced expression alterations of hippocampal Ser9 phosphorylated glycogen synthase kinase 3β (p-Ser9 GSK 3β), Ser133 phosphorylated cAMP response element-binding protein (p-Ser133 CREB), and brain-derived neurotrophic factor (BDNF). Moreover, PPD attenuated the CORT-induced increase in GSK 3β activity and decrease in dendritic spine density in the hippocampus. In vitro, 14-3-3 ζ protein specifically bound to p-Ser9 GSK 3β polypeptide. PPD promoted the binding and subsequently decreased GSK 3β activity. Conclusion: These findings demonstrated the antidepressant-like effects of PPD on the CORT-induced mouse depression model and indicated a possible target-based mechanism. The combination of PPD with the 14-3-3 ζ protein may promote the binding of 14-3-3 ζ to p-GSK 3β (Ser9) and enhance the inhibition of Ser9 phosphorylation on GSK 3β kinase activity, thereby activating the plasticity-related CREBeBDNF signaling pathway.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.53-60
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• 2016

Abiotic-stressed tobacco stems as a non-wooden biomass were analyzed for their chemical characteristics. Light-stressed tobacco stems (LST) have a relatively high nitrogen concentration, much more extractive content, and a similar amount of lignin and higher contents of acid sugars than those of Non stressed tobacco (NST). It also has low cellulose crystallinity and a high degree of condensation. Guaiacyl units having a lower molecular weight distribution consist of rich lignin. Tension stressed tobacco (TST) growth differentiation under tensile stress was significantly different between normal tissue and cell walls, with the exception of the slightly higher cellulose crystallinity observed for.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.5
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• pp.441-446
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• 2013

In the present study, the anti-depressant like effect of methyl gallate (MG) isolated from the stem bark of Acer barbinerve was examined in ICR mice. Body weight (BDW) and blood glucose (BDG) levels significantly decreased in the repeated restraint stress (RRS) group (2 h/day for 14 days) compared to the no stress (NS) group. To examine the effect of MG on RS-induced BDW loss and hypoglycemia, MG (10 mg/kg) and the anti-depressant fluoxetine (10 mg/kg) were administered daily for 14 days. Orally administered MG and fluoxetine significantly attenuated the RS-induced BDW loss and hypoglycemia. Interestingly, MG administered mice showed increased BDG levels in the normal and glucose feeding condition. Chronic RS-subjected mice showed immobilized and depressed behaviors. The effect of MG on the depressed behaviors was evaluated using the tail-suspension test (TST) and the forced swimming test (FST). In both tests, RS-induced immobilized behaviors were significantly reversed in MG and fluoxetine administered groups. Taken together, MG significantly attenuated the RS-induced BDW loss, hypoglycemia, and depressed behaviors. Considering that decreased BDG levels (hypoglycemia) can cause depression, MG may exert its anti-depressant like effect by preventing hypoglycemia. Our results suggest that MG isolated from A. barbinerve can exert anti-depressant like effect, and could be used as a new and natural anti-depressant therapy.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.4
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• pp.307-312
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• 2007

This study was performed to evaluate sleep efficiencies and conditions for comfortable sleep based on the analysis of sleep efficiency and MST under four thermals conditions ($22^{\circ}C,\;24^{\circ}C,\;26^{\circ}C,\;30^{\circ}C$). Five female subjects who have similar life cycle and sleep patterns were participated for the sleep experiment. Their age was from 20 to 22 years old. They were healthy, and had regular sleep with consistent bed and wakeup time. It was checked whether they had a good sleep before the night of experiment. Experiments were performed in an environmental chamber using thermo-hygrostat. The physiological signal (EEG) for sleep stage were obtained from C3-A2 and C4-Al electrode sites. Sleep stages were classified, then SWS latency and SWS/TST were calculated for the evaluation for sleep efficiencies on thermal conditions. As results, mean skin temperature for comfort sleeping was $34.5{\sim}35.4^{\circ}C$. Considering sleep efficiency and mean skin temperature, indoor room temperature of upper limit was $28.1^{\circ}C$.

• Korean Journal of Community Nutrition
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• v.3 no.3
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• pp.341-348
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• 1998

This study was performed to investigated the difference in the nutritional status of normal children and children with suboptimal iron status. Two hundred and sixty children from 5th grade were divided into 2 groups(normal group and suboptimal group) according to the hematologic parameters of iron(RBC count, hemoglobin, serum ferritin). Normal group was composed of 71 male and 81 female and suboptimal group was consisted of 65 male and 43 female. Fat percentage of children from suboptimal group was 18.9%, which was significantly lower than 22.1% of normal group(p<0.05). TST and MAC of suboptimal group were also lower than those of normal group(p<0.05). Mean intakes of energy, protein, thiamin, riboflavin, iron were lower than those in normal group(p<0.05). suboptimal female students showed 1197.6㎉ of energy intake(63.0% of RDA) and 0.56㎎ of thiamin intake(56% of RDA). Mean RBC count, hematocrit, hemoglobin, ferritin(p<0.01) and FEP(p<0.05) of suboptimal group were lower than those of normal group. Thirty-nine point seven percent of children from suboptimal group was observed with having gastrointestinal disease which was significantly higher than 22.1% of normal group. (Korean J Community Nutrition 3(3) : 341∼348, 1998)