• Steel and Composite Structures
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• 제50권4호
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• pp.403-418
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• 2024

In this paper, vibration and energy absorption characteristics of a nanostructure which is composed of two embedded porous annular/circular nanoplates coupled by a viscoelastic substrate are investigated. The modified couple stress theory (MCST) and the Gurtin-Murdoch theory are applied to take into account the size and the surface effects, respectively. Furthermore, the structural damping effect is probed by the Kelvin-Voigt model and the mathematical model of the problem is developed by a new hyperbolic higher order shear deformation theory. The differential quadrature method (DQM) is employed to obtain the out-of-phase and in-phase frequencies of the structure in order to predict the dynamic response of it. The acquired results reveal that the vibration and energy absorption of the system depends on some factors such as porosity, surface stress effects, material length scale parameter, damping and spring constants of the viscoelastic foundation as well as geometrical parameters of annular/circular nanoplates. A bird's-eye view of the findings in the research paper offers a comprehensive understanding of the vibrational behavior and energy absorption capabilities of annular/circular porous nanoplates. The multidisciplinary approach and the inclusion of porosity make this study valuable for the development of innovative materials and applications in the field of nanoscience and engineering.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.367-370
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• 2012

Background: Breast cancer is the most commonly diagnosed cancer in women worldwide In Iran, it ranks first among cancers diagnosed in women and is the fifth most common cause of death. The aim of this study was to present the mortality trends from breast cancer for Iranian women during a period of almost a decade, in order to provide update information regarding the likely future. Methods: We analyzed National death Statistic reported by the Iranian Ministry of Health and Medical Education from 1995 to 2004 to generate annual mortality rates/100,000, overall, by age group (<15, 15-49 and ${\geq}50$ years of age) and age standardized rate (ASR). Results: The age standardized mortality rate of breast cancer increased dramatically during these years from 1.40 to 3.52 per 100,000 and its mortality was increasing 151.4% for Iranian women, although it seemed that the rate leveled off from 2002 to 2004. Moreover the increasing rate was higher for those aged between 15-49 compared to age >50 years old. Conclusion: There is an increasing trend for breast cancer mortality in Iran. Thus, health education programs to rectify the lack of women awareness about breast cancer signs and effective screening are urgently needed.

• 건축역사연구
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• 제20권6호
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• pp.57-76
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• 2011

This study is on the pedagogical convention of architectural history in Korea, especially that of Western Architecture. Recent institutional change in architectural school in Korea has caused overall restructuring of academic program. In spite of extension in the field of history there was no progress of method and way of thinking. There is no change in the point of view to see the western architecture and its history as a unique and specialized phenomenon in the civilization of mankind. Because of no recognition about for what, for whom, and how to, and because of orientalism, the cultural position of western architectural history and its narrative was not asked. With the help of post-colonialism, de-constructivism and critical historiography this paper tries to show the fundamental premise of western architectural history as a myth and show its prejudice as not being justifiable. The background of the discourse there has been a representation effect with regard to knowledge as a power. we need to escape from this kind of cognitional frame With the analysis of the its premise and narrative we can find it is a historical construct that was made in the age of imperialism. In fact it has a lot of false information and problematic point of view. The Identity and originality of western architecture and its history has no logical reason or foundation if we think that it depends on the difference and comparison with other civilization. For example the explanation of its historical origin western architecture has big difference with Islamic architecture in spite of the resemblance each other. This paper try to show several reasons that discourse of western architectural history can not be survived any longer. So we need to reconstruct new pedagogy with deconstruction for the students of non western, or Korean students. Because it has important effect to see and think about architecture and its history.

• Nutrition Research and Practice
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• 제12권6호
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• pp.512-520
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• 2018

BACKGROUND/OBJECTIVES: The 6-23 months for infants is the longest period in the "first 1,000 days" of life. This period is very important for child development, so complementary feeding (CF) practices should be optimized to maximize children's potential for growth and development. The aim of this study was to analyze the CF practices and nutritional status of children aged 6-23 months. SUBJECTS/METHODS: For this cross-sectional study, 392 children aged 6-23 months were selected using stratified random sampling. Socio-demographic data were collected through interviews. CF practices, collected by interviews and repeated 24-hour food recall method, were the timely introduction of CF, minimum meal frequency, dietary diversity and minimum acceptable diet, consumption food rich in proteins and vitamin A. Nutritional status was assessed using the indicators of underweight, wasting and stunting. To analyze the association between socio-demographic indicators and CF with nutritional status, the chi-square test with a confidence interval of 95% was used. RESULTS: Results showed that 39% were exclusively breastfed, only 61% received prolonged breastfeeding and 50% received timely introduction of CF. Minimum meal frequency was met by 74% of subjects, but dietary diversity and minimum acceptable diet were only realized in 50% and 40% of the children, respectively. The prevalence of underweight, wasting, and stunting were 26%, 23%, and 28%, respectively. Age of the child, birth order, birth weight, parents' education level, family size and incidence of fever and diarrhea during the previous two weeks were associated with underweight, while child's birth order, fathers' education level, mother's age, family size, completion of the age-appropriate vaccination and fish consumption frequency were associated with wasting. Age of the child, incidence of fever and acute respiratory infection, and fortified food consumption were associated with stunting. CONCLUSIONS: Suboptimal CF practices and high prevalence of underweight, wasting and stunting were found among children aged 6-23 months old in Aceh. These results highlight the need to improve CF and nutritional status.

• Structural Engineering and Mechanics
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• 제85권1호
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• pp.29-53
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• 2023

High-strength shielding concrete against gamma radiation is a priority for many medical and industrial facilities. This paper aimed to investigate the gamma-ray shielding properties of high-strength hematite concrete mixed with silica fume (SF) with nanoparticles of lead dioxide (PbO₂), tungsten oxide (WO₃), and bismuth oxide (Bi₂O₃). The effect of mixing steel fibres with the aforementioned binders was also investigated. The reference mixture was prepared for high-strength concrete (HSCC) containing 100% hematite coarse and fine aggregate. Thirteen mixtures containing 5% SF and nanoparticles of PbO₂, WO₃, and Bi₂O₃ (2%, 5%, and 7% of the cement mass, respectively) were prepared. Steel fibres were added at a volume ratio of 0.28% of the volume of concrete with 5% of nanoparticles. The slump test was conducted to workability of fresh concrete Unit weight water permeability, compressive strength, splitting tensile strength, flexural strength, and modulus of elasticity tests were conducted to assess concrete's engineering properties at 28 days. Gamma-ray radiation of 137Cs emits photons with an energy of 662 keV, and that of 60Co emits two photons with energies of 1173 and 1332 keV were applied on concrete specimens to assess radiation shielding properties. Nanoparticles partially replacing cement reduced slump in workability of fresh concrete. The compressive strength of mixtures, including nanoparticles was shown to be greater, achieving 94.5 MPa for the mixture consisting of 7.5 PbO2. In contrast, the mixture (5PbO₂-F) containing steel fibres achieved the highest values for splitting tensile, flexural strength, and modulus of elasticity (11.71, 15.97, and 42,840 MPa, respectively). High-strength shielded concrete (7.5PbO2) showed the best radiation protection. It also showed the minimum concrete thickness required to prevent the transmission of radiation.

• Advances in concrete construction
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• 제15권3호
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• pp.179-190
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• 2023

The effect of glass fibres (GF) and polypropylene fibres (PPF) on the fresh properties and mechanical properties of lightweight concrete (LWC) exposed to high temperatures is investigated in this study. In this study, fifteen LWC mixtures were carried out in three different groups reinforced with PPF or GF fibers by 0%, 0.2%, and 0.4% by volume of concrete. The first group included aluminum powder (AP) as an air agent at 0.03% with the normal weight coarse aggregate (NWCA) by 100% of the weight of coarse aggregate. In the second group, 33% of the NWCA weight was replaced by lightweight coarse aggregate (LWCA). In the third group, 67% of the NWCA weight was replaced by LWCA. The slump, unit weight, Compressive strength (CS), tensile strength (TS), and flexural strength (FS) were examined. For two hours, the CS and FS were subjected to elevated temperatures of 200℃, 400℃, and 600℃, in addition to microstructure analysis of concrete. In comparison to the reference mixture, the fresh properties and bulk density of LWC decreased with the use of the air agent or the replacement of 67% of the NWCA with LWCA. As a result of the fiber addition, both the slump test and the bulk density decreased. The addition of fibers increased the CS; the highest CS was 38.5 MPa when 0.4% GF was added, compared to 28.9 MPa for the reference mixture at the test age of 28 days. In addition, flexural and TS increased by 53% and 38%, respectively, for 0.4% GF mixes. As well as, adding 0.4% GF to LWC maintained a higher CS than other mixtures.

• 융합경영연구
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• 제5권4호
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• pp.29-38
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• 2017

Organizational commitment (OC) is one of the most important attitudes and/or organizational variables. It is one of the important factors for increasing organizational performance and consequently it has a significant impact on productivity enhancement. Study of behavior in the workplace due to the great importance of manpower compared to other resources within the organization is of great importance too. OC is a psychological state which represents kind of desire, a need and a requirement for continuing employment in an organization. It is considered as one of the most influential factors in getting success and competitive advantage in today's organizations. Investigating effect of financial and non-financial variables on financial performance for a long-term has engaged the minds of researchers. Intensification of competition in markets has increased importance of recognizing competitive advantage patterns and their effect on financial performance (FP).This research conducted to provide a better understanding for people as well as for aggregation of a research subject OC and FP is compared in Indian banking sector by taking sample of 2 public and two private banks the correlation between the OC and FP and the results included a positive and significant correlation. Desired FP to increase wealth is an essential and obvious issue. According to the issued subjects, today, commitments and their impact on FP of companies have become increasingly important. In Indian banks the correlation between the OC & FP were found significant.

• 시큐리티연구
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• 제42호
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• pp.277-308
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• 2015

최근 일본인 인질사태와 시리아 조종사의 화형, 우리나라 김군의 IS테러단체의 가입과 같은 사건이 발생하면서 우리나라도 IS테러와 관련하여 더 이상 예외가 아니라고 할 수 없을 것이다. 또한 IS테러집단은 전 세계인을 상대로 특히 영웅이 되고 싶고 비판력이 약하며 소외되어 있는 10대 청소년을 대상으로 대화나 게임 등의 SNS를 통한 IS가입을 권유하면서 자국 내 국민은 물론 다른 나라의 불만세력이 있거나 운둔형인 국민들까지 언제든지 테러단체에 가입 할 수 있는 환경을 만들면서 IS테러단체의 테러행위는 자국 내 국민에 의해서도 외국인이나 이주민에 의해서도 발생될 수 있는 상황이 되었다. 따라서 이 연구에서는 이러한 IS테러단체의 테러행위에 대한 심각성을 인식하고, IS테러단체의 공습확대에 따른 자국 내 테러발생 위험성에 대해 외국의 사건사례 등을 검토하여 이를 예방하고 대응할 수 있는 방안을 모색해 보고자 하였다. 그 결과 IS테러단체의 공습확대에 따른 자국 내 테러발생 위험성성은 존재하며 그 원인에 대한 대응 방안은 다음과 같다. 우선, IS테러단체의 사이트에 대한 내국인의 접근을 막기 위한 대테러방지법이 마련되어져야 하며, 다음으로는 각 기관과의 테러정보에 대한 교류와 협력 그리고 이를 통한 역할분담이 이루어져 테러가 발생했을 경우 신속하면서도 적절한 대책이 이우어져야 한다. 마지막으로 자국민 특히 10대 청소년에 대한 테러관련 교육과 테러에 대비한 안전강화프로그램이 개발 및 실행되어야 할 것이다.

• 대한약침학회지
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• 제25권3호
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• pp.216-223
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• 2022

Objectives: Oxidative stress plays a key role in chronic and acute brain disorders and neuronal damage associated with Alzheimer disease (AD) and other neurodegeneration symptoms. The neuroprotective effects of berberine and Berberis vulgaris (barberry) root extract against apoptosis induced by hydrogen peroxide (H₂O₂) in the human SH-SY5Y cell line were studied. Methods: The methanolic extraction of barberry root was performed using a maceration procedure. Oxidative stress was induced in SH-SY5Y cells by H₂O₂, and an MTT assay was applied to evaluate the neuroprotective effects of berberine and barberry root extract. The cells were pretreated with the half maximal inhibitory concentration (IC₅₀) of each compound (including berberine, barberry root extract, and H₂O₂), and the anti-apoptotic effects of all components were investigated using RT-PCR. Results: The SH-SY5Y cell viability increased in both groups exposed to 75 and 150 ppm barberry extract compared with that in the H₂O₂-treated group. The data showed that exposing SH-SY5Y cells to 30 ppm berberine significantly increased the cell viability compared with the H₂O₂-treated group; treatment with 150 and 300 ppm berberine and H₂O₂ significantly decreased the SH-SY5Y cell viability and was associated with berberine cytotoxicity. The mRNA levels of Bax decreased significantly under treatment with berberine at 30 ppm compared with the control group. A significant increase in Bcl-2 expression was observed only after treatment with the IC₅₀ of berberine. The expression level of Bcl-2 in cells exposed to both berberine and barberry extracts was also significantly higher than that in cells exposed to H₂O₂. Conclusion: The outcomes of this study suggest that treatment of SH-SY5Y cells with barberry extract and berberine could suppress apoptosis by regulating the actions of Bcl-2 family members.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6101-6104
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• 2012

Background: Breast cancer accounts about one million from total annual ten million new diagnosed cases of neoplasia worldwide and is the main cause of death due to cancer in women. Tamoxifen is the most popular selective estrogen receptor modulator used in anti estrogen treatments. Tamoxifen must be converted into its metabolite endoxifen for biologic effects; this conversion process is catalysed by highly polymorphic cytochrome P450 2D6 (CYP2D6). This study surveyed copy number variation of the CYP2D6 gene and its possible correlation with Tamoxifen resistance in breast cancer patients. Methods: This case control study was performed on samples taken from 79 patients with breast cancer who used tamoxifen in Yazd and Tehran Cities, Iran. Real time reactions were conducted for 10 healthy samples using the comparative $C_t$ (Cycles threshold) method, each pair of genes being compared and samples with ratios around 1 were taken as control samples. Proliferation reactions were done by Real-Time PCR ABI Prism 7500. All registered data were transformed into SPSS 15 program and analyzed. Results: Efficiency of PCR for both CYP2D6 and ALB genes was 100%. From all 23 drug resistant patients 21.7% had one copy, 47.8% two copies and 30.4% had three copies. Also from all 56 drug sensitive patients, 26.8% had one copy, 51.8% two copies and 21.4% had three copies. The percentage of patients with one and two copies was similar between two groups but patients with three copies were more likely to belong to the drug resistant group more. Odd ratios for one and two copies were 0.759 and 0.853 respectively, indicating possible protective effects while that for three copies was 1.604. Conclusions: Based on our study there is no significant link between CYP2D6 gene copy numbers and tamoxifen resistance in women with breast cancer. But more studies considering other influencing factors appear warranted.