• Journal of Korean Neurosurgical Society
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• v.57 no.4
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• pp.307-310
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• 2015

We report a case of a paradoxical response of a tuberculoma in the brain mimicking a brain tumor. A 76-year-old woman presented with a 2 week history of headache, dysarthia, and orthopnea. Brain magnetic resonance images (MRI) revealed two rim-enhancing lesions on the pons and occipital lobe, and chest computed tomography showed randomly distributed miliary nodules. The tentative diagnosis was tuberculosis (TB) of the brain and lung. She complained of right hemiparesis and worsening general weakness after taking the anti-TB medication. On the monthly follow-up images, the enhanced lesions were enlarged with increased perfusion and choline/creatinine ratio, suggesting a high grade glioma. A surgical resection was completed to diagnose the occipital lesion, and the tuberculoma was pathologically confirmed by a positive TB-polymerase chain reaction. The anti-TB medication was continued for 13 months. A follow-up MRI showed decreased size of the brain lesions associated with perilesional edema, and the clinical symptoms had improved. Brain tuberculoma could be aggravated mimicking brain malignancy during administration of anti-TB medication. This paradoxical response can be effectively managed by continuing the anti-TB drugs.

• Journal of the Korean Society of Radiology
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• v.8 no.5
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• pp.261-264
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• 2014

In this study, $Gd_2O_2S:Tb^{3+}$ was used as the component of the intensifying screen, and this study aims at analysis of fluorescent feature depending on the increase of tube voltage using spectrometer. When the released fluorescence was measured according to the increase of tube voltage, blue, green and red was observed, among which, $^5D_4-^7F_5$ which is applicable to green, was strongest. In addition, when the fluorescent of 50 kVp and 120 kVp were compared, 50 kVp was proved to release only 9.56% fluorescence of 120 kVp. In case when tube voltage which is higher than 100 kVp is used for the X-ray using $Gd_2O_2S:Tb^{3+}$ intensifying screen, the amount and strength of the fluorescence reaching the film increase drastically, so attention is demanded to get images of proper concentration.

• Journal of Magnetics
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• v.13 no.3
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• pp.110-113
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• 2008

In this study, heavy rare earth garnet $Tb_2Bi_1Ga_1Fe_4O_{12}$ powders were fabricated by a sol-gel and vacuum annealing process. The crystal structure was found to be single-phase garnet with a space group of Ia3d. The lattice constant $a_0$ was determined to be 12.465 ${\AA}$. From the analysis of the vibrating sample magnetometer (VSM) hysteresis loop at room temperature, the saturation magnetization and coercivity of the sample are 7.64 emu/g and 229 Oe, respectively. The N$\acute{e}$el temperature($T_N$) was determined to be 525 K. The M$\ddot{o}$ssbauer spectrum of $Tb_2Bi_1Ga_1Fe_4O_{12}$ at room temperature consists of 2 sets of 6 Lorentzians, which is the pattern of single-phase garnet. From the results of the M$\ddot{o}$ssbauer spectrum at room temperature, the absorption area ratios of Fe ions on 24d and 16a sites are 74.7% and 25.3%(approximately 3:1), respectively. These results show that all of the non-magnetic Ga atoms occupy the 16a site by a vacuum annealing process. Absorption area ratios of Fe ions are dependent not only on a sintering condition but also on the temperature of the sample. It can then be interpreted that the Ga ion distribution is dependent on the temperature of the sample. The M$\ddot{o}$ssbauer measurement was carried out in order to investigate the atomic migration in $Tb_2Bi_1Ga_1Fe_4O_{12}$.

• Korean Journal of Materials Research
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• v.16 no.7
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• pp.455-459
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• 2006

Coincidence Doppler Broadening (CDB) of positron annihilation spectroscopy was applied to analyze defects in the chemical state of Department of Physics, $Gd_2O_2S$:Tb intensifying screens. The screen samples were irradiated by 80 MV X-rays in hospital and were used for 0, 2, 4, and 6 years respectively. There was a positive relationship between the S-parameter values and time of exposure to X-rays. Most of the defects were indicated to have been generated by X-rays. A 1D CDB was developed in order to reduce the background noise, and the S-parameter values of the $Gd_2O_2S$:Tb intensifying screens, using the 1D CDB, varied between 0.4974 and 0.4991.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.675-678
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• 2009

$Fe_2O_3,\;Ag_2O,\;CaWO_4$ and $Gd_2O_2S$:Tb loaded on titanium dioxide photocatalysts (P25, Degussa) were prepared by a calcination. Their composite films containing water-born polyurethane used as a material for immobilization were obtained by spray coating technique. The photocatalytic activity of the titanium dioxide films was characterized by decrease of UV-vis absorption spectra for methylene blue and gas chromatography for photocatalytic decomposition of formaldehyde diluted in water. It was shown that the $Gd_2O_2S$:Tb modified titanium dioxide films had good photocatalytic properties and followed the first-order kinetic model with regard to photocatalytic decoloration of methylene blue. Especially in formaldehyde photodegradation experiment, decrease rate of concentration of the titanium dioxide films with $Gd_2O_2S$:Tb modifying was about 35% larger than that of the unloaded titanium dioxide film.

• Korean Journal of Materials Research
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• v.13 no.8
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• pp.509-513
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• 2003

In the present investigation, $La^{3＋}$ and $Ce^{V}$ ions were substituted for $Y^{3＋}$ in the $YBO_3$: Tb in various concentrations. It has been found that these phosphors form solid solutions within limited concentration ranges Excitation and emission spectra under 254 nm and 147 nm were investigated for these phosphors to evaluate influences of $La^{3＋}$ and $Ce^{3＋}$ ions on brightness and CIE color coordinates. It has been observed that brightness of $(Y, La)BO_3$: Tb under 254 nm and 147 nm when $La^{3＋}$ ions are added show an increase of 2.7 times and 1.25 times, respectively. On the other hand, emission intensities of peaks in $Y_{0.8-x}$ $BO_3$: $Tb_{0.2}$ , $Ce_{x}$ show continuos decrease as $Ce^{3＋}$ / content is increased from 0 to 0.4. CIE color coordinates of prepared phosphors show yellowish green which is needed to be improved to be used for display applications.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.487-497
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• 2021

The purpose of this study is to identify factors affecting length of stay(LOS) and death in tuberculosis(TB) patients by disease type, patient characteristic, admission and disease characteristic, and hospital characteristic from 2008 to 2017. Survey data was using Korean national hospital discharge in-depth survey data produced by Korea Disease Control and Prevention Agency. Study subjects were 10,634 inpatients with TB(A15, A16, A17, A18, A19, U88.0, U88.1, U84.30, U84.31) and analyzed frequency, chi-square test, Fisher's exact test, and logistic regression by using STATA 13.0. As a study result, the type of TB(extrapulmonary TB, multidrug-resistant TB, extensively drug-resistant TB), sex(woman), age(35-49, 50-64, 65-74, 75 years old or older), admission type(outpatient department), CCI(1-2 point, 3 point over), hospital location(metropolitan city) and bed size(300-499, 500-999, over 1000) were significantly influence LOS. Also, the type of TB(extrapulmonary TB, extensively drug-resistant TB), sex(woman), age(50-64, 65-74, 75 years old or older), residence(small town/rural), admission type(outpatient department), CCI(1-2 point, 3 point over), hospital location(provincial) were significantly influence death. In conclusion, the existing tuberculosis management has been patient management with rapid diagnosis and treatment following early detection. But other studies should be carried out for the system that identifies and supports high-risk groups of the long-term length of stay in hospital or high mortality rates as a result of treatment.

• Journal of Biomedical Engineering Research
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• v.38 no.1
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• pp.25-31
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• 2017

Testing TB in chest X-ray images is a typical method to diagnose presence and magnitude of PTB lesion. However, the method has limitation due to inter-reader variability. Therefore, it is essential to overcome this drawback with automatic interpretation. In this study, we propose a novel method for detection of PTB using SegNet, which is a deep learning architecture for semantic pixel wise image labelling. SegNet is composed of a stack of encoders followed by a corresponding decoder stack which feeds into a soft-max classification layer. We modified parameters of SegNet to change the number of classes from 12 to 2 (TB or none-TB) and applied the architecture to automatically interpret chest radiographs. 552 chest X-ray images, provided by The Korean Institute of Tuberculosis, used for training and test and we constructed a receiver operating characteristic (ROC) curve. As a consequence, the area under the curve (AUC) was 90.4% (95% CI:[85.1, 95.7]) with a classification accuracy of 84.3%. A sensitivity was 85.7% and specificity was 82.8% on 431 training images (TB 172, none-TB 259) and 121 test images (TB 63, none-TB 58). This results show that detecting PTB using SegNet is comparable to other PTB detection methods.

• Tuberculosis and Respiratory Diseases
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• v.84 no.1
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• pp.74-83
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• 2021

Background: This study compared the treatment outcomes of patients with multidrug-resistant tuberculosis (MDR-TB) before and after the implementation of public-private mix (PPM). Factors affecting treatment success were also investigated. Methods: Data from culture-confirmed pulmonary MDR-TB patients who commenced MDR-TB treatment at Pusan National University Hospital between January 2003 and December 2017 were retrospectively reviewed. Patients were divided into two groups in terms of PPM status: pre-PPM period, patients who commenced MDR-TB treatment between 2003 and 2010; and post-PPM period, patients treated between 2011 and 2017. Results: A total of 176 patients were included (64 and 112 in the pre- and post-PPM periods, respectively). 36.9% of the patients were resistant to a fluoroquinolone or a second-line injectable drug, or both. The overall treatment success rate was 72.7%. The success rate of post-PPM patients was higher than that of pre-PPM patients (79.5% vs. 60.9%, p=0.008). Also, loss to follow-up was lower in the post-PPM period (5.4% vs. 15.6%, p=0.023). In multivariate regression analysis, age ≥65 years, body mass index ≤18.5 kg/m², previous TB treatment, bilateral lung involvement, and extensively drug-resistant (XDR)- or pre-XDR-TB were associated with poorer treatment outcomes. However, the use of bedaquiline or delamanid for ≥1 month increased the treatment success. Conclusion: The treatment success rate in MDR-TB patients was higher in the post-PPM period than in the pre-PPM period, particularly because of the low rate of loss to follow-up. To ensure comprehensive patient-centered PPM in South Korea, investment and other support must be adequate.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.171-171
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• 2013

최근에 희토류 이온이 도핑된 형광체를 램프, 플라즈마, 디스플레이 패널, 음극선관, 광전 소자에 응용하기 위한 연구에 많은 노력이 경주되고 있다. 특히 희토류 이온은 4f-껍질에 존재하는 전자의 독특한 성질 때문에 좁은 밴드폭과 강한 발광 특성을 나타내므로 발광 다이오드, 자석, 촉매, 디스플레이 패널용 형광체로 개발되고 있다, 본 연구에서는 고효율의 녹색과 적색 형광체를 개발하기 위하여 모체 결정은 SrSnO3, 활성제 이온은 Eu (유로퓸) 와 Tb (테르븀)을 선택하여 도핑하였다. 합성된 형광체 분말의 회절상을 XRD로 측정한 결과에 의하면, Eu3+와 Tb3+의 함량비에 관계없이 모든 세라믹 분말은 JCPDS #74-1298에 제시된 회절상과 일치하였으며, 주 피크는 $31.3^{\circ}$, $44.9^{\circ}$, $55.8^{\circ}$에서 최대값을 갖는 (110), (200), (211)면에서 발생한 회절 신호이며, 이밖에도 $22.04^{\circ}$, $65.4^{\circ}$, $74.3^{\circ}$에서 약한 회절 피크를 갖는 (100), (220), (013)면의 신호들이 관측되었다. Eu3+ 이온의 함량비가 0.05 mol 인 경우에 (110)과 (211) 피크의 세기가 최대값을 나타내었고, Eu3+의 함량비가 증가함에 따라 두 피크의 세기는 점점 감소하였다. XRD의 데이터를 Scherrer의 식에 대입하여 계산한 결정 입자의 크기는 Eu3+ 이온이 도핑된 경우에는 0 mol에서 최소의 크기를 나타내었고, Tb3+ 이온이 도핑된 경우에 입자의 크기는 0.05 mol에서 최소이었고 0 mol에서 최대값을 보였다. SEM으로 촬영한 표면 형상의 변화를 관측한 결과, Eu3+의 함량비가 0.15 mol인 경우에, 결정 입자의 평균 크기는 400~450nm이며, Tb3+의 함량비가 0.05 mol인 경우에, 결정 입자의 평균 크기는 270~290nm 이었으며, 입자의 형상은 균일하게 분포하는 구형 형태을 보였다. Eu3+와 Tb3+ 이온의 함량비가 점점 증가함에 따라 미립자들이 서로 뭉쳐져서 각각 약 720 nm와 580 nm의 크기를 갖는 큰 입자를 형성하였고, 불규칙적인 분포를 나타내었다. 여기 파장 293 nm에서 Tb3+가 도핑된 SrSnO3:Tb3+ 형광체 분말의 발광 스펙트럼을 측정한 결과에 의하면, Tb3+의 함량비에 관계없이 모든 시료는 주 피크인 550 nm (녹색)와 상대적으로 세기가 약한 500, 590, 630 nm에서 발광 스펙트럼을 나타내었다. 주 피크의 발광 세기는 0.01 mol~0.15 mol에서는 증가 하였고, 더욱 함량비를 증가함에 따라 급격하게 감소하였다. 이 현상은 활성제 이온의 mol 비가 증가함에 따라 이온 사이의 거리가 가까워져서 서로 뭉치는 현상이 주도적으로 작용하여 발광의 세기가 현저히 감소하는 것으로 판단된다. 0.10 mol 일 때 세기가 가장 강한 녹색 형광 신호를 얻었다. 여기 파장 400nm에서 Eu3+가 도핑된 SrSnO3:Eu3+ 형광체 분말의 형광 스펙트럼은 Eu3+의 함량비에 관계없이 590, 619, 696 nm에서 관측되었다. Eu3+의 몰 비가 0.01~0.05 mol 영역에서 619 nm가 주 피크이나, 몰 비가 더욱 증가함에 다라 주 피크의 파장은 590 nm로 이동하였다. 한편, 696 nm의 발광세기는 몰 비가 증가함에 따라 더욱 증가하였다.