• Korean Journal of Materials Research
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• v.5 no.4
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• pp.476-482
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• 1995

TbFeCo 박막의 Facing Targets Sputtering System 조건, 조성 및 시효 처리에 따른 광자기적 특성과 산화 특성을 조사하였다. XPS와 AES를 통하여 보호막 없이 제조된 TbFeCo 박막의 표면에는 Co에 우선하여 Tb과 Fe가 안정한 산화물의 형태로 존재하며, 표면에서 3.2nm 깊이부터는 산화되지 않은 TbFeCo 박막이 존재함을 확인하였다. TbFeCo 박막을 시효 시킴에 따라 Fe 산화층의 두께는 거의 변화가 없었으며, Tb Oxide 층만이 증가하였다. TbFeCo 박막은 사용된 기판의 종류나 제조조건에 따라 열적 안정성에 큰 차이를 보였다.

• Tuberculosis and Respiratory Diseases
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• v.85 no.2
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• pp.111-121
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• 2022

Multidrug-resistant tuberculosis (MDR-TB) is caused by an organism that is resistant to both rifampicin and isoniazid. Extensively drug-resistant TB, a rare type of MDR-TB, is caused by an organism that is resistant to quinolone and one of group A TB drugs (i.e., linezolid and bedaquiline). In 2018, the World Health Organization revised the groupings of TB medicines and reclassified linezolid as a group A drug for the treatment of MDR-TB. Linezolid is a synthetic antimicrobial agent in the oxazolidinone class. Although linezolid has a good efficacy, it can cause substantial adverse events, especially hematologic toxicity. In both TB infection and linezolid mechanism of action, mitochondrial dysfunction plays an important role. In this concise review, characteristics of linezolid as an anti-TB drug are summarized, including its efficacy, pathogenesis of hematologic toxicity highlighting mitochondrial dysfunction, and the monitoring and management of hematologic toxicity.

• Journal of Korea Spatial Information System Society
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• v.7 no.1 s.13
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• pp.13-24
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• 2005

Objects, which change their positions over time such as cars, are called moving objects. Trajectories of a moving object have large volumes because trajectories are accumulated. Efficient indexing techniques for searching these large volumes of trajectories are needed in the moving object databases. Especially the TB-tree which supports bundling trajectories is suitable for processing combined queries which have 2 steps: first step is selecting trajectories (range search), next is selecting the parts of each trajectory (trajectory search). But the TB-tree has unnecessary disk accesses cause of lack of spatial discrimination in range queries. In this paper, we propose and implement the splitting polity which can reduce dead spaces of non-leaf node in order to process range queries efficiently. The policy has better performance about range queries than the TB-tree as well as the advantages of the TB-tree, such as highly space utilization and efficient trajectory extraction. This paper shows that the newly proposed split policy has better performance in processing the range queries than that of the TB-tree by experimental evaluation.

• Tuberculosis and Respiratory Diseases
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• v.81 no.4
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• pp.274-280
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• 2018

Background: The risk of tuberculosis (TB) infection among health care workers (HCWs) is higher than as noted among workers in the general population. The prevalence and risk factors of TB infection among HCWs were assessed in a tertiary hospital in South Korea, resulting in a conclusion of an intermediate TB burden within the country. Methods: This cross-sectional study enrolled HCWs who underwent a QuantiFERON-TB Gold In-Tube (QFT-GIT) test to detect the presence of a latent TB infection (LTBI), in patients admitted to a tertiary hospital in South Korea in 2017. The departments of the hospital were divided into TB-related and TB-unrelated departments, which were based on the risk of exposure to TB patients. In this sense, the risk factors for LTBI, including current working in the TB-related departments, were analyzed. Results: In this case, a total of 499 HCWs (54 doctors, 365 nurses and 80 paramedical personnel) were enrolled in this study. The median age of the subjects was 31 years (range, 20-67 years), 428 (85.8%) were female, and 208 (41.7%) were working in the TB-related departments. The prevalence of LTBI was 15.8% based on the QFT-GIT. Additionally, the prevalence of experience of exposure to pre-treatment TB patents was higher among HCWs working in the TB-related departments, than among HCWs working in the TB-unrelated departments (78.8% vs. 61.9%, p<0.001). However, there was no significant difference in the prevalence of LTBI between the two groups (17.3% vs. 14.8%, p=0.458). On a review of the multivariate analysis, only the factor of age was independently associated with an increased risk of LTBI (p=0.006). Conclusion: Broadly speaking, the factor of age was associated with an increased risk of LTBI among the HCWs in South Korea. However, those workers current working in the TB-related departments was not associated with an increased risk of LTBI.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.846-853
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• 1995

In order to study electronic structures for locally disordered systems, we have developed a first-principle self-con-sistent-spin-polarized real space band method (TB-LMTO-R), which combines the tight-binding(TB) linear-muffin-tin orbital(LMTO) band rrethod and the recursion(R) rrethod. The TB-LMTO-R rrethod has been applied to fer-romagnetic bec Fe, hcp Co, and fcc Ni. With varying cluster sizes, recursion coefficients, and the order of the TB-Hamiltonian, we have calculated the local density of states(LDOS) and magnetic moments. It is found that the calculation with 5,000 atoms cluster, 40 continued fractions, and the second-order TB-Hamiltonian yields a conver¬gent result in agreement with those from the conventional LMTO. In this way, we have demonstrated a physical transparency of the TB-LMTO-R method as a real space description.

• Imaging Science in Dentistry
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• v.52 no.2
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• pp.171-179
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• 2022

Purpose: The aim of this study was to assess the accuracy of cone-beam computed tomographic (CBCT) images obtained using different voxel sizes in measuring trabecular bone microstructure in comparison to micro-CT. Materials and Methods: Twelve human skull bones containing posterior-mandibular alveolar bone regions were analyzed. CBCT images were obtained at voxel sizes of 0.075mm(high: HI) and 0.2mm(standard: Std), while microCT imaging used voxel sizes of 0.06 mm (HI) and 0.12 mm (Std). Analyses were performed using CTAn software with the standardized automatic global threshold method. Intraclass correlation coefficients were used to evaluate the consistency and agreement of paired measurements for bone volume (BV), percent bone volume (BV/TV), bone surface (BS), trabecular thickness (TbTh), trabecular separation (TbSp), trabecular number (TbN), trabecular pattern factor(TbPf), and structure model index (SMI). Results: When compared to micro-CT, CBCT images had higher BV, BV/TV, and TbTh values, while micro-CT images had lower BS, TbSp, TbN, TbPf, and SMI values (P<0.05). The BV, BV/BT, TbTh, and TbSp variables were higher with Std voxels, whereas the BS, TbPf, and SMI variables were higher with HI voxels for both imaging methods. For each imaging modality and voxel size evaluated, BV, BS, and TbTh were significantly different(P<0.05). TbN, TbPf, and SMI showed statistically significant differences between imaging methods(P<0.05). The consistency and absolute agreement between micro-CT and CBCT were excellent for all variables. Conclusion: This study demonstrated the potential of high-resolution CBCT imaging for quantitative bone morphometry assessment.

• Journal of Life Science
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• v.32 no.2
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• pp.135-141
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• 2022

Thymosin β-4 (TB4) is a small peptide composed of 43 amino acids. To obtain sufficient biologically active mouse TB4 economically, we cloned and overexpressed this gene in an Escherichia coli system. With the isopropyl β-D-1-thiogalactopyranoside induction of the E. coli transformant, TB4 fusion protein with intein- and chitin-binding domain was successfully expressed in the soluble fraction within the E. coli cell. The TB4-intein - chitin-binding domain fusion protein was purified from the soluble fraction of E. coli cell lysate. The affinity chromatography with chitin beads and dithiothreitol-mediated intein self-cleavage reaction releases the TB4 peptide into the stripping solution. Sodium dodecyl sulphate - polyacrylamide gel electrophoresis and Western blot analyses were used to confirm that the recombinant TB4 peptide was produced with the expected size of 5 kDa. We found that the recombinant TB4 stimulated cell migration in the transwell plate chamber assay. After 18 hr of the treatment of the recombinant TB4 with 1 ng/ml concentration, the migration of the HT1080 cell was increased by 20% compared with that of the chemically synthesized TB4. The recombinant TB4 was also observed to promote the healing of a wound area in C57BL/6 mice by as high as 35% compared with that of the chemically synthesized TB4. These results suggest that the recombinant TB4 has better biological activity for cell migration and wound healing than that of the chemically synthesized TB4 peptide.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.331-337
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• 2009

Background: The whole-blood interferon-gamma release assay (QuantiFERON-TB Gold [QFT-G]: Cellestis, Carnegie, Victoria, Australia) has been studied primarily for the use of diagnosing active pulmonary tuberculosis (TB) or latent TB. In the present study, the usefulness of QFT-G was evaluated for the diagnosis of extra-pulmonary tuberculosis (EP-TB). Methods: From June 2006 to February 2009, we evaluated the usefulness of QFT-G in patients (n=65) suspected with EP-TB, retrospectively. The diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the QFT-G assay were analyzed. Results: EP-TB was diagnosed in 33 (51%) participants. The overall sensitivity, specificity, PPV, and NPV of the QFT-G assay for EP-TB were 78%, 79%, 81%, and 77%, respectively. Of the 33 with EP-TB, 14 (42%) were diagnosed with TB pleurisy, 7 (21%) with TB lymphadenitis, 7 (21%) with intestinal TB, and 5 (15%) with EP-TB in other sites. In subgroup analyses according by site of infection, the QFT-G showed 86% sensitivity, 64% specificity, and 78% NPV in TB pleurisy. On the other hand, the sensitivity, specificity, and NPV of the assay were 71%, 83% and 71%, respectively in TB lymphadenitis, and 86%, 100% and 88%, respectively in intestinal TB. Among the patients with suspected alternative site EP-TB, the sensitivity, specificity, and NPV of the assay were 50%, 80% and 67%, respectively. Conclusion: The QFT-G assay showed moderate diagnostic accuracy in EP-TB. However, negative QFT-G assay does not exclude EP-TB because of the low NPV of this assay.

• Tuberculosis and Respiratory Diseases
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• v.70 no.2
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• pp.125-131
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• 2011

Background: The clinical manifestation of $M.$ $tuberculosis$ infection ranges from asymptomatic latent infection, to focal forms with minimal symptoms and low bacterial burdens, and finally to advanced tuberculosis (TB) with severe symptoms and high bacillary loads. We investigated the diagnostic sensitivity of the whole-blood interferon-${\gamma}$ release assay according to the wide spectrum of clinical phenotypes. Methods: In patients diagnosed with active TB that underwent $QuantiFERON^{(R)}$ (QFT) testing, the QFT results were compared with patients known to be infected with pulmonary tuberculosis (P-TB) and extra-pulmonary TB (EP-TB). In addition, the results of the QFT test were further analyzed according to the radiographic extent of disease in patients with P-TB and the location of disease in patients with EP-TB. Results: There were no statistical differences in the overall distribution of QFT results between 177 patients with P-TB and 84 patients with EP-TB; the positive results of QFT test in patients with P-TB and EP-TB were 70.1% and 64.3%, respectively. Among patients with P-TB, patients with mild extents of disease showed higher frequency of positive results of QFT test than that of patients with severe form (75.2% vs. 57.1%, respectively; p=0.043) mainly due to an increase of indeterminate results in severe P-TB. Patients with TB pleurisy showed lower sensitivity by the QFT test than those with tuberculous lymphadenitis (48.8% vs. 78.8%, respectively; p=0.019). Conclusion: Although QFT test showed similar results between overall patients with P-TB and EP-TB, individual sensitivity was different according to the radiographic extent of disease in P-TB and the location of disease in EP-TB.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.897-902
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• 2006

This study was carried out to investigate the possibility for utilization of waste materials and the characteristics of pork by feeding citrus byproducts. The groups consisted of the pork without citrus byproduct (TB-0) and the pork fed with 6% and 10% citrus byproduct during growing and fattening period (TB-1). The contents of moisture, crude protein, crude fat, crude ash, vitamin $B_1$ and $B_2$, total amino acids, and caloric were not significantly different between TB-0 and TB-1 (p>0.05). The contents of cholesterol and the magnesium of TB-1 were lower than those of TB-0. Palmitic acid was the most abundant among saturated fatty acids while oleic acid was the most abundant among unsaturated fatty acids in both groups. In case of sensory score, the color and aroma of raw meat and taste, texture, juiciness and palatability of boiled meat were not influenced by feeding of citrus byproduct. But the flavor preference of boiled meat of TB-1 was higher than that of TB-0.