• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.396-401
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• 2013

Alternating copolymers, poly[9-(2-octyl-dodecyl)-9H-carbazole-alt-4,7-di-thiophen-2-yl-benzo[1,2,5]thiadiazole] (PCD20TBT) and poly[9,10-bis-(2-octyl-dodecyloxy)-phenanthrene-alt-4,7-di-thiophen-2-yl-benzo[1,2,5]thiadiazole] (PN40TBT), were synthesized by the Suzuki coupling reaction. The copolymers were soluble in common organic solvents such as chloroform, chlorobenzene, 1,2-dichlorobenzene, tetrahydrofuran and toluene. The maximum absorption wavelength and the band gap of PCD20TBT were 535 nm and 1.75 eV, respectively. The maximum absorption wavelength and the band gap of PN40TBT were 560 nm and 1.97 eV, respectively. The HOMO and the LUMO energy level of PCD20TBT were -5.11 eV and -3.36 eV, respectively. As for PN40TBT, the HOMO and the LUMO energy level of PCD20TBT were -5.31 eV and -3.34 eV, respectively. The polymer solar cells (PSCs) based on the blend of copolymer and PCBM (1 : 2 by weight ratio) were fabricated. The power conversion efficiencies of PSCs based on PCD20TBT and PN40TBT were 0.52% and 0.60%, respectively. The short circuit current density ($J_{SC}$), fill factor (FF) and open circuit voltage ($V_{OC}$) of the device with PCD20TBT were $-1.97mA/cm^2$, 38.2% and 0.69 V. For PN40TBT, the $J_{SC}$, FF, and $V_{OC}$ were $-1.77mA/cm^2$, 42.9%, and 0.79 V, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3611-3615
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• 2012

Objective: The objective of this study was to establish the diagnostic accuracy, specificity and sensitivity of fine needle aspiration cytology(FNAC) for intra-oral tumors, comparing with histopathology as the gold standard. Materials and methods: Forty cases of FNA cytology from intraoral tumors was performed in AFID along with the demographic data and clinical information and then diagnosed at AFIP, Rawalpindi. Then the cytology results obtained per FNAC were compared with the histopathological biopsy results of the same lesions. The following variables were recorded for each patient: Age, gender, site of biopsy, diagnosis. The data were entered and analyzed using Open-epi version 2.0. Diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value were calculated. Cohen Kappa was further applied to compare the agreement between the biopsy and FNAC diagnoses. A p-value of < 0.05 was considered as statistically significant. Results: Among the total patients included in the study there were 24 males and 16 females, with a ratio of 1.5:1. Age of the patients ranged from 24 to 80 years with a mean of 52 years. A total of six sites were aspirated from the oral cavity with maximum (11) aspirates taken from alveolar ridge. The results of FNAC revealed that there were 32 malignant and 8 benign aspirates. Confirmation through histopathological analysis came for 31/32 malignant cases while one was falsely given positive for malignancy on FNAC. Among a total of 40 cases, 31(77%) cases diagnosed were found to be malignant and remaining 9(23%) were benign. The FNAC results revealed 32 malignant and 8 benign lesions. Histopathology of the subsequent surgically excised specimen showed malignant lesions in 31(77%) and benign in 9(23%) patients. As a whole, it was found that the absolute sensitivity for introral FNAC was 100% and specificity 89% with positive predictive value of 97% and negative predictive value of 100%. Conclusion: Cytological diagnosis was almost corroborative with final histopathological diagnosis in all cases, with very few exceptions, exhibiting high diagnostic accuracy.

• Spatial Information Research
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• v.18 no.4
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• pp.1-11
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• 2010

Unlike the previous studies which have focused on 2-dimensional urban characteristics, this paper presents statistical models explaining urban heat island(UHI) effect by 3-dimensional urban morphologic information and addresses its policy implications. 3~dimensional informations of Columbus, Ohio arc captured from LiDAR data and building boundary informations are extracted from a building digital map, Finally NDV[ and temperature data are calculated by manipulating band 3, band 4, and thermal hand of LandSat images. Through complicated data processing, 6 independent variables(building surface area, building volume, height to width ratio, porosity, plan surface area) are introduced in simple and multiple linear regression models. The regression models are specified by Box-Tidwell method, finding the power to which the independent variable needs to raised to be in a linearity. Porosity, NDVI, and building surface area are carefully chosen as explanatory variables in the final multiple regression model, which explaining about 57% of the variability in temperatures. On reducing UHI, various implications of the results give guidelines to policy-making in open space, roof garden, and vertical garden management.

• Journal of Educational Research in Mathematics
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• v.27 no.1
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• pp.113-135
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• 2017

The purpose of the research was to develop an analysis framework for Korean mathematics textbooks from a critical mathematics education perspective. For this, we conducted a comprehensive literature review regarding critical theory, critical education, and critical mathematics education. Based on the literature review, we derived a preliminary framework for textbook analysis. To validate the preliminary framework delphi survey was carried out twice with 21 expert panelists in the field of mathematics education and multicultural education. The first delphi survey was conducted with open-ended questions to investigate diverse opinions regarding educational goals, contents, and teaching methods of critical mathematics education. The second delphi survey was conducted with Likert-type scale and it was analyzed using Mean, Contents Validity Ratio, Degree of Consensus. As the result of the whole research procedures, the final analysis framework was developed consisting of four categories: classical knowledge, community knowledge, communicative knowledge, and political knowledge. A development of the analysis framework from a critical mathematics education perspective could give a significant impact on the mathematics curriculum or mathematic teacher education in the Korea and a meaningful initial step for the effort of practicing critical mathematics education. It is expected that this study could not only incite consideration for the better mathematics education but also expand the prospect of research and practice in mathematics education. This study would provide a new paradigm of future mathematics education with which to teach and guide students to become members of world civil society with mathematical power and critical competency.

• Journal of Korean Society of Steel Construction
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• v.29 no.5
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• pp.389-400
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• 2017

Based on U-shaped composite beam, the new form of AU-composite beam were developed to create economical and efficient components reducing the cost and shortening the length of construction work. Because the U-shaped sections are open and needs to be fixed by topping concrete securely. Therefore, it is required to maintain the U-shaped sections in a structure and to work in the safe condition through construction. It also requires accessories that resist the horizontal shear force for synthesis between the top and bottom of the U-shaped section. To reinforce these shortcomings, a shear connector has been developed with various purposes of steel plate anchors. In this study, the steel plate anchors were directly tested and the shear force was evaluated by the horizontal shear force. The experiment was divided into two types, depending on the applicable deck plates. As a result of the experiment, the continuous type specimens showed greater resistance in both strength and displacement than the ones of stud anchor specimen. In discontinuous type case, due to shear simulations and simple element analysis, the less increase the ratio of width to height and the more shear strength decreased. Thus, the shear strength equation of the stud anchor was modified to suggest the new shear strength based on the testing results.

• Journal of Chest Surgery
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• v.35 no.11
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• pp.807-811
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• 2002

Due to its less invasive nature and superior visual field, video-assisted thoracescopic excision of mediastinal mass is thought to be comparable to open thoracotomy. Material and Method : From January 1995 to August 2001, the medical records of 38 patients who underwent video-assisted thoracoscopic excision of mediastinal mass was retrospectively analyzed. The outcome of these patients were compared with 5 patients who converted to thoracotomy Result: Male to female ratio was 13(34.2%) : 25(65.8%), and mean age was 39.2$\pm$35.4 years. Regarding the pathology, there were 8 neurilemmomas(21.1%), 6 thymic cysts (15.8%), 5 teratomas(13.2%), 5 ganglioneuromas(13.2%), 4 bronchogenic cysts(10.5%), 3 pericardial cysts(7.9%), 3 thymomas(7.9%), and 2 lymphangiomas(5.3%). The mean operation time was 110.6$\pm$7.0 minutes, mean postoperative tube stay was 4.2$\pm$0.4 days, mean postoperative hospital stay was 5.2$\pm$0.4 days, and mean number of injection of analgesics was 1.9$\pm$0.4 times. Although the mean values for the above indices were less than those of the thoracotomy conversion cases, they were statistically insignificant. Postoperative complications of videoassisted thoracoscopic excision included chylothorax, prolonged air leakage, and unilateral phrenic nerve palsy, all of which recovered before patient discharge. There was, however, permanent unilateral ptosis in one patient. Conclusion : As video-assisted thoracoscopic excision of mediastinal mass is safe, less painful, conducive to earlier recovery and cosmetically more appealing, a more active application of this technique is recommeded.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.1
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• pp.41-46
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• 2011

The artificial aggregates (AAs) composing of 2 wastes, coal bottom ash and dredged soil (7 : 3, weight ratio) were fabricated as a function of red mud contents,0~30 wt% using direct sintering method at $1050{\sim}1250^{\circ}C$ for 10 min, and those physical properties were evaluated. Especially, in order to analyze the red mud addition effect on the bloating phenomenon of AAs manufactured, the specific gravity and water absorption were measured and studied linked with the microstructural observation results. The lightening of AAs was enhanced due to increased bloating with increasing temperature and red mud contents. The AAS sintered at $1050{\sim}1150^{\circ}C$ showed well-developed black-coring structure, but for the specimens containing red mud sintered over $1200^{\circ}C$ generated excessive liquid and gas caused by reduction of $Fe_2O_3$, thus the black-coring part was gradually burst open out of shell of AAs. Particularly, all specimens containing 30 wt% red mud was burst up when sintered over $1100^{\circ}C$. The AAs containing no red mud sintered at $1200^{\circ}C$ had a specific gravity of about 1.2 and those containing 20 wt% had below 1.0 which are characters of lightweight aggregate.

• Journal of Environmental Health Sciences
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• v.32 no.5 s.92
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• pp.404-411
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• 2006

이 연구의 목적은 유치원에서 총 휘발성 유기화합물의 농도를 평가하고, 총 휘발성 유기화합물 농도와 대표적인 8개 방향족 화합물의 상관관계를 조사하는데 있다. 도시에 위치한 11개 유치원의 실내와 실외에서 각각 30개, 11개의 지역시료를, 시골에 위치한 4개 유치원에서는 각각 10개, 4개의 시료를 테낙스 튜브를 이용하여 오전에 1-2시간 채취하였다. 채취한 시료는 열탈착하여 가스크로마토그래피-질량분석기로 분석하였다. 13가지 물질을 각각의 표준물질로 개별 정량하여 이중 빈번히 발견되는 8가지 방향족 유기화합물은 상관관계 평가에 사용하였다. 총 휘발성 유기화합물은 톨루엔을 기준으로 정량하였다. 도시에 위치한 유치원 실내의 총 휘발성 유기화합물 농도가 높았고, 조사 건수의 50%가 환경부 및 교육인적자원부의 가이드라인($400{\mu}g/m^{3}$)을 초과하였다. 도시지역의 유치원 실내 및 실외의 기하평균은 각각 $387.9{\mu}g/m^{3}$과 $134.9{\mu}g/m^{3}$이었고, 시골지역 유치원에서는 각각 $189.6{\mu}g/m^{3},;74.4{\mu}g/m^{3}$이었다. 톨루엔, 크실렌, 에틸벤젠, 정량한 유기 화합물 총합, 총 휘발성 유기화합물은 기하정규분포를 하였다. 벤젠, 톨루엔, 에틸벤젠, 크실렌(BTEX)은 도시에 위치한 유치원에서 농도도 높고, 총 휘발성 유기화합물중 함량도 높았고, 시골지역에서는 농도와 상대적 함량이 낮았다. 도시지역에서는 총 휘발성 유기화합물 중 BTEX의 비중이 25.2%였고 정량한 13가지 유기화합물 중에서는 35.6%를 차지하였다. BTEX 각각 개별물질은 미국 환경보호청이 제시하는 일일 노출 기준량(Reference Concentration; RfC) 보다는 현저히 낮았다. 총 휘발성 유기화합물읜 농도는 실내가 실외 보다 높았다(I/O ratio 2.5). BTEX의 상대적 함량도 실내가 실외보다 높아 실내에도 발생원이 있음을 암시하고 있다. 자료 분석결과 유치원 실내의 벤젠은 실외로부터 유입되고 있었고, 톨루엔, 에틸벤젠, 크실렌은 실외뿐 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5385-5388
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• 2015

Background: Gastric cancer is the most common gastrointestinal cancer and a leading cause of cancer mortality in Nepal. Survival of gastric cancer patients depends on the stage at which diagnosis is made. The aim of this study was to analyze the presentation and outcomes of gastric cancer patients treated at a tertiary care hospital in Nepal. Materials and Methods: A retrospective analysis of 140 consecutive histologically proven gastric adenocarcinoma cases managed at the Department of Surgery, Tribhuvan University Teaching Hospital, Kathmandu, Nepal for the period of January 2009 to December 2013 was carried out. Results: One hundred forty out of the total 186 patients with histologically proven gastric adenocarcinoma, were admitted for surgery. The mean age was $59.6{\pm}12.4yrs$ (range 29 to 78 yrs) and the male: female ratio was 2:1. Sixty three (45%) patients featured Tibeto-Burman descent though this ethnic group accounts for only 18% of the Nepalese population. Two-thirds or more patients presented with abdominal pain, anorexia, weight loss and/or vomiting. In 86 (61.5%) of the patients the tumor was located in the lower $3^{rd}$ of the stomach and in only 15% of the patients the tumor was located at the upper $3^{rd}$. Early gastric cancer was diagnosed postoperatively in only 4%. In 54%, the disease was locally advanced and metastatic lesions were found in 14% of the patients. Subtotal (73) or total (11) curative gastrectomies (D1, D1+ or D2) were performed in 84 (60%) patients with average lymph node retrieval of $16.6{\pm}8.2$. Palliative gastrectomies or procedures were performed in 23% of the patients and no intervention (open & close/biopsy) was employed in 15% of the patients. Perioperative morbidity was seen in 10% and mortality in 4%. Three, four and five year survival rates up to the recent follow-up were 17.9%, 11.9% and 8.3%, respectively. Conclusions: Gastric cancer in Nepal is usually diagnosed at an advanced stage and has a poor prognosis. Thus, early detection is the key to improve the survival of gastric cancer patients.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.12
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• pp.1702-1710
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• 2017

Objective: The study examined the effect of condensed tannins (CT) containing Ficus infectoria and Psidium guajava leaf meal mixture (LMM) supplementation on nutrient metabolism, methane emission and performance of lambs. Methods: Twenty four lambs of ~6 months age (average body weight $10.1{\pm}0.60kg$) were randomly divided into 4 dietary treatments (CT-0, CT-1, CT-1.5, and CT-2 containing 0, 1.0, 1.5, and 2.0 percent CT through LMM, respectively) consisting of 6 lambs each in a completely randomized design. All the lambs were offered a basal diet of wheat straw ad libitum, oat hay (100 g/d) along with required amount of concentrate mixture to meet their nutrient requirements for a period of 6 months. After 3 months of experimental feeding, a metabolism trial of 6 days duration was conducted on all 24 lambs to determine nutrient digestibility and nitrogen balance. Urinary excretion of purine derivatives and microbial protein synthesis were determined using high performance liquid chromatography. Respiration chamber study was started at the mid of 5th month of experimental feeding trial. Whole energy balance trials were conducted on individual lamb one after the other, in an open circuit respiration calorimeter. Results: Intake of dry matter and organic matter (g/d) was significantly (p<0.05) higher in CT-1.5 than control. Digestibility of various nutrients did not differ irrespective of treatments. Nitrogen retention and microbial nitrogen synthesis (g/d) was significantly (p<0.01) higher in CT-1.5 and CT-2 groups relative to CT-0.Total body weight gain (kg) and average daily gain (g) were significantly (linear, p<0.01) higher in CT-1.5 followed by CT-1 and CT-0, respectively. Feed conversion ratio (FCR) by lambs was significantly (linear, p<0.01) better in CT-1.5 followed by CT-2 and CT-0, respectively. Total wool yield (g; g/d) was linearly (p<0.05) higher for CT-1.5 than CT-0. Methane emission was linearly decreased (p<0.05) in CT groups and reduction was highest (p<0.01) in CT-2 followed by CT-1.5 and CT-1. Methane energy (kcal/d) was linearly decreased (p<0.05) in CT groups. Conclusion: The CT supplementation at 1% to 2% of the diet through Ficus infectoria and Psidium guajava LMM significantly improved nitrogen metabolism, growth performance, wool yield, FCR and reduced methane emission by lambs.