• Steel and Composite Structures
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• 제43권1호
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• pp.31-54
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• 2022

This paper is concerned with the buckling behavior of functionally graded graphene reinforced porous nanocomposite beams based on the finite element method (FEM) using two variables trigonometric shear deformation theory. Both Young's modulus and material density of the FGP beam element are simultaneously considered as grading through the thickness of the beam. The finite element approach is developed using a nonlocal strain gradient theory. The governing equations derived here are solved introducing a 3-nodes beam element, and then the critical buckling load is calculated with different porosity distributions and GPL dispersion patterns. After a convergence and validation study to verify the accuracy of the present model, a comprehensive parametric study is carried out, with a particular focus on the effects of weight fraction, distribution pattern of GPL reinforcements on the Buckling behavior of the nanocomposite beam. The effects of various structural parameters such as the dispersion patterns for the graphene and porosity, thickness ratio, boundary conditions, and nonlocal and strain gradient parameters are brought out. The results indicate that porosity distribution and GPL pattern have significant effects on the response of the nanocomposite beams, and the results allows to identify the most effective way to achieve improved buckling behavior of the porous nanocomposite beam.

• Advances in materials Research
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• 제12권2호
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• pp.161-177
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• 2023

This paper proposes an analytical method to investigate the free vibration behaviour of new functionally graded (FG) carbon nanotubes reinforced composite beams based on a higher-order shear deformation theory. Cosine functions represent the material gradation and material properties via the thickness. The kinematic relations of the beam are proposed according to trigonometric functions. The equilibrium equations are obtained using the virtual work principle and solved using Navier's method. A comparative evaluation of results against predictions from literature demonstrates the accuracy of the proposed analytical model. Moreover, a detailed parametric analysis checks for the sensitivity of the vibration response of FG nanobeams to nonlocal length scale, strain gradient microstructure-scale, material distribution and geometry.

• 한국임상수의학회지
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• 제28권3호
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• pp.310-313
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• 2011

6년령 암컷 시츄견이 체중 부하하는 파행을 동반한 좌측 앞다리굽이관절 주위의 종괴를 주증으로 충북대학교 동물의료센터에 내원하였다. 초음파 검사결과 피막에 싸인 고에코성의 종괴가 앞다리굽이관절에서 확인되었으며, 방사선학적 검사 결과 흉부나 복부로의 전이 소견은 관찰되지 않았다. Gun-biopsy 샘플을 이용한 세포학적 검사 결과 세포부동증, 다형성 등 악성의 지표를 보이는 종양세포들이 다수 확인되었으며, 치료를 위하여 좌측 전지의 절단술이 시행되었다. 절제된 조직의 조직병리학적 검사 결과 악성 말초 신경집종으로 진단되었다. 환자는 수술 후 보행이나 전신활력 등이 양호하였으나 술 후 5개월째에 좌측 전지 절단술을 시행했던 부위의 피하 종괴와 다른 두 곳의 피부 종괴가 발생하였다. 종괴는 수술적으로 제거되었으며, 절제된 조직의 세포학적 검사 결과 원발 종양과 유사한 소견으로 종양이 재발되었음이 확인되었다. 술 후 종양의 또 다른 재발을 막고 의심되는 폐 전이의 속도를 늦추기 위한 목적으로 cyclophosphamide와 piroxica을 병용한 화학요법이 시행되었다. 첫 수술로부터 26개월이 경과한 현재 환자는 만족할만한 삶의 질을 유지하며 생존하고 있다. 개의 악성 말초 신경집 종양에서 적극적인 외과적 절제와 metronomic chemotherapy의 병행은 효과적인 치료법이 될 수 있다.

• 대한의용생체공학회:의공학회지
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• 제38권5호
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• pp.256-263
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• 2017

By using the buildup characteristics of the radiophotoluminescence glass dosimeter(RPLGD), it is aimed to help the measurement of the accurate dose by measuring the radiation dose according to the time of the glass element. Five glass elements were arranged on the table and the source to image receptor distance(SID) was set to 100 cm for the build-up radiation dose measurement of the fluorescent glass dosimeter glass element(GD-352M). Radiation doses and saturation rates were measured over time according to irradiation time, with the tube voltage (30, 60, 90 kVp) and tube current (50, 100 mAs) Repeatability test was repeated ten times to measure the coefficient of variation. The radiation dose increased from 0.182 mGy to 12.902 mGy and the saturation rate increased from 58.3% with increasing exposure condition and time. The coefficient of variation of the glass elements of the fluorescent glass dosimeter was ranged from 0.2 to 0.77 according to the X - ray exposure conditions. X - ray exposure showed that the radiation dose and saturation rate were increased with buildup characteristics, and degeneration of glass elements was not observed. The reproducibility of the variation coefficient of the radiation generator was included within the error range and the reproducibility of the radiation dose was excellent.

• 자동차안전학회지
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• 제9권1호
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• pp.32-36
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• 2017

In order to reduce the damage of life and property caused by an automobile accident, we should design new car models and safety standard with reference to the data analysis and in-depth investigation of the accident. In-depth research and analysis of the current world other than the police investigation team (GIDAS, iGLAD, NHTSA, etc.) and collect in-depth data. Going to develop a safety policy to make it much safer cars based on this data. However, the country still does not have the advantage of KIDAS data Safety Policy Direction. In KNCAP tests, there is nothing in order to protect far side passengers even if far side impact causes approximately 50% injured people. Based on DBs like KIDAS (Korean In-Depth Accident Study) and GIDAS, far side passengers got injured as much as near side passengers did. So as to protect far side passengers, KNCAP has to change the test method of side crashes. In this study, injury severities to compare with ES-2, World SID and Thor dummies and the movements of far and near side passengers, SLED TEST was used.

• 대한디지털의료영상학회논문지
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• 제13권2호
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• pp.71-76
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• 2011

Because interventional procedure operates looking at premier as real time when perate intervention enemy, by patient is revealed during suitableness time in radiation, side effect such as radiation injury of skin is apt to happen. It established by purpose of study that measure exposure dose that patient receives about these problem, and find solution for radiation injury and repletion method. In this study, we used Rando phantom of identical structure with the human body which becomes accomplished with 4 branch ingredient of the attempt and system equivalent material them and absorbed dose were measured by TLD. According to the laboratory, it shows that operations such as TFCA procedure or uterine myoma embolization are more dangerous than TACE procedure. If both operations are inspected during a short time, it is not affected in being bombed. However, it can lead to palliative agenesis or depilate, definitive agenesis only if operations are repeated more than three times. Dose distibution based on experiment, to reduce radiation exposure to patients result from reduction of scatter ray as we control field size of radiation and protection of side organs except for tumor. also we knew that we can protect patients form radiation exposure, if we increas SOD and decrease SID.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5477-5482
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• 2012

Background: The HER-2/neu gene is altered in 15-20% of breast cancer patients. Immunohistochemistry (IHC) is considered to be the most cost-effective method for HER-2 detection in many countries. Approximately 8,000 new cases of breast cancer are observed annually in Iran. The aims of this study were to conduct a systematic review of the literature on the rate of HER-2-positive breast cancer diagnosed by IHC in Iran. Methods: A systematic search of the medical literature using the Medline/PubMed, ISI and SID databases revealed articles published in the English and Persian languages evaluating HER-2-positive breast cancer in Iran. Results: From 22 studies, 3,033 patients were evaluated, of whom 1,350 were diagnosed as HER-2-positive by IHC HER-2 testing. The mean percentage of HER-2-positive patients was 44.5%, which is higher than that recorded in international statistics. Results of this meta-analysis showed a significant heterogeneity between ratios. There was a statistically significant difference between the results of pre- and post implementation of 2007 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guideline. IHC HER-2 testing has been performed in Iran for over 10 years. Similar to many other countries, before establishment of an infrastructure for IHC diagnostic tests, HER-2 testing was routinely performed in Iran. Our study showed that the statistics reported from Iran varied widely; for instance, the rate of HER-2-positive cases varied from 23.3% to 81.0%. Conclusions: Our results demonstrate that the lack of standardization and harmonization of this test have led to marked variations in breast cancer diagnosis in Iran.

• Asian Pacific Journal of Cancer Prevention
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• 제16권3호
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• pp.1219-1224
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• 2015

Background: To date several common mutations in BRCA1 and BRCA2 associated with breast cancer have been reported in different populations. However, the common BRCA1 and BRCA2 mutations among breast cancer patients in Iran have not been described in detail. Materials and Methods: To comprehensively assess the frequency and distribution of the most common BRCA1 and BRCA2 mutations in Iranian breast cancer patients, we conducted this meta-analysis on 13 relevant published studies indentified in a literature search on PubMed and SID. Results: A total of 11 BRCA1 and BRCA2 distinct common mutations were identified, reported twice or more in the articles, of which 10 (c.2311T>C, c.3113A>G, c.4308T>C, c.4837A>G, c.2612C>T, c.3119G>A, c.3548A>G, c.5213G>A c.IVS16-92A/G, and c.IVS16-68A/G) mutations were in BRCA1, and 1 (c.4770A>G) was in BRCA2. The mutations were in exon 11, exon 13, intron 16, and exon 20 of BRCA1 and exon 11 of BRCA2. All have been previously reported in different populations. Conclusions: These meta analysis results should be helpful in understanding the possibility of any first true founder mutation of BRCA1/BRCA2 in the Iranian population. In addition, they will be of significance for diagnostic testing, genetic counseling and for epidemiological studies.

• 대한수의학회지
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• 제45권2호
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• pp.251-254
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• 2005

An 11-year-old, 3.3 kg, male Maltese dog was referred to Veterinary Teaching Hospital of Konkuk University because of diarrhea and severe anemia. Abnormal physical examination findings included left submandibular lymph node enlargement, pale mucous membrane, cataract, and bloody diarrhea. Results of hematologic examination revealed a marked lymphocytosis resulting in leukocytosis and the markedly increased numbers of small, well-differentiated lymphocytes in the peripheral blood. Serum biochemical abnormalities consisted of elevated AST and ALP, hyperphosphatemia, hypoglycemia, and hypoalbuminemia. Radiographic examination showed cardiomegaly and hepatosplenomegaly. Results of urinalysis included bilirubinuria and proteinuria. Based on results of examination described above, chronic lymphocytic leukemia was diagnosed. Chemotherapy was initiated with cyclophosphamide ($300mg/m^2$, IV once every 2 weeks), vincristine ($0.75mg/m^2$, IV once every 2 weeks, alternating weeks with the cyclophosphamide), and plus prednisolone ($50mg/m^2$, PO, SID for a week, then $20mg/m^2$, PO every other day). The response to chemotherapy was partially present. This study first demonstrates clinicopathological findings and chemotherapeutic response of chronic lymphocytic leukemia in Korea.

• 생명과학회지
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• 제26권8호
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• pp.875-880
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• 2016

진핵세포의 원형질막은 외부환경으로부터 세포를 격리하는 물리적인 장벽뿐만 아니라, 선택적 물질수송, 신호전달등 중요한 기능을 수행한다. 원형질막의 세포질쪽 지질층은 주로 Phosphatidylethanolamine (PE), Phosphatidylserine (PS), Phosphatidylinositides (PIs) 등의 인지질로 구성되어 있는데, 다양한 단백질들이 이들과 직접 결합하거나 이들의 성질을 이용해 원형질막으로 위치된다. 본 연구에서는 원형질막의 안쪽 지질층에 존재하는 특정 인지질과 결합하여, 원형질막에 위치되는 단백질을 과발현시켰을 때 나타나는 세포의 모양변화를 분석하였다. 이를 위해 PS와 PI등과의 선택적 결합으로 원형질막에 위치하는 단백질들과 소수성 또는 정전기적 상호작용으로 원형질막으로 위치되는 단백질들을 HEK293T세포에 과발현시켜 보았다. 그 결과, 대조군으로 사용한 EGFP 단백질과 PI4P에 선택적으로 결합하는 EGFP-P4M-SidM단백질의 발현은 세포의 모양변화를 유도하지 않았다. 반면, PI(4,5)P₂에 결합하는 EGFP-PLCδ1(PH), PI(3,4,5)P₃에 결합하는 EGFP-AKT1(PH), PI4P와 PI(4,5)P₂에 결합하는 OSH2(PH)x2-EGFP의 발현은 세포의 크기가 줄어드는 수축현상이 일어나면서, Lamilapodia나 Filopodia가 형성되는 것을 확인할 수 있었다. 반면에, PS결합을 통해 원형질막에 위치되는 Lact-C2-EGFP과 소수성결합에 의해 원형질막에 위치되는 ApPDE4 long-form인 L(N20)-EGFP이나, 정전기적인 결합을 통해 원형질막으로 위치되는 ApPDE4 short-form인 S(N-UCR1-2)-EGFP단백질의 경우는 세포의 크기가 줄어드는 수축현상은 일어나지만 Lamilapodia나 Filopodia와 같은 모양변화는 나타나지 않는 것을 확인할 수 있었다. 본 연구를 통해, 특정 인지질에 결합하여 원형질막에 위치되는 단백질들이 각각의 인지질 결합 특성에 따라 분류 가능한 세포의 모양변화가 일어남을 확인할 수 있었다.