در هنگام جستجو کلمه در قسمت عنوان میتوانید کلمات مورد جستجو را با کاراکتر (-) جدا کنید.
کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Civil Engineering Infrastructures Journal
- نوع مقاله: Journal Article
- کلمات کلیدی: Seismic Behavior,Incremental Dynamic Analysis,Offshore Platforms,Performance Levels
- چکیده:
- چکیده انگلیسی: It is generally accepted that performance-based design has to be reliability-based. Seismic performance evaluation is based on nonlinear dynamics and reliability theory taking into account uncertainties during analysis. Considering the economic importance of jacket type offshore platforms, the present research aims to assess the seismic performance of offshore steel platforms. In this study, three platforms located in the Persian Gulf were modeled using three dimensional structural modeling tools. Each platform was modeled and analyzed using both rigid and pinned connections. Reliability analysis was performed in accordance with Federal Emergency Management Agency (FEMA) guidelines using the results of incremental dynamic analysis for the three platforms. The results showed that platforms possessing rigid connections provide the desired confidence level of FEMA for the performance level of collapse prevention while only one platform with pinned connections was able to provide the desired confidence level.
- انتشار مقاله: 08-02-1397
- نویسندگان: Mohammad Reza Mohammadizadeh,Kazem Vahidi,Hamid Reza Ronagh
- مشاهده
- جایگاه : پژوهشی
- مجله: Computational Engineering and Physical Modeling
- نوع مقاله: Journal Article
- کلمات کلیدی: Shear and axial failures,Local and global collapse,Non-ductile reinforced concrete buildings,Fragility curves
- چکیده:
- چکیده انگلیسی: The brittle behavior of older non-ductile reinforced concrete buildings such as shear-axial failure in columns can cause lateral instability or gravity collapse. Hence, the attempt is to assess the collapse potential through fragility curves. Current research focuses on fragility assessment of these buildings emphasizing on shear-axial failure using two well-established methods; empirical limit state material versus ASCE/SEI 41-13 recommendations. To this aim, two 2D reinforced concrete models (3 and 5-story) according to typical detail of existing buildings in Iran were modeled using two aforementioned modeling approaches and analyzed under monotonic analysis and incremental dynamic analysis (IDA). In the following, seismic fragility assessment were carried out by means of obtained results from IDA. The results of fragility curves showed that, collapse capacity of buildings modelled by ASCE/SEI 41-13 are more than empirical method and fewer cases can pass the level of safety probability of failure suggested by ASCE/SEI-41.
- انتشار مقاله: 22-10-1396
- نویسندگان: Mohammad Reza Azadi Kakavand,Mohammad Khanmohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Avicenna Journal of Phytomedicine
- نوع مقاله: Journal Article
- کلمات کلیدی: Rats,oxidative stress,Antioxidant,hepatotoxicity,Carbon tetrachloride,Artemisia dracunculus L
- چکیده:
- چکیده انگلیسی: Objective: The present study was conducted to investigate the antioxidant and hepatoprotective activity of the hydro-alcoholic extract of aerial parts of Artemisia dracunculus (HAAD) against CCl4-induced hepatotoxicity in rats.
Materials and Methods: The antioxidant activity was evaluated by reducing power, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 20-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Rats were pre-treated with either 50, 100, and 200 mg/kg of HAAD or silymarin (100 mg/kg; served as the positive control group) for 15 days and they received a single dose of CCl4 on the last day. Hepatoprotective effects were investigated by assessment of serum biochemical enzymes such as alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total protein (TP), total bilirubin (TB), malondialdehyde (MDA), and antioxidant enzymes (SOD, CAT, GST and GSH), along with histopathological studies.
Results: Total phenolic content was 197.22±3.73 mg gallic acid equivalent/g HAAD dry weight. HAAD indicated powerful activity in FRAP, DPPH and ABTS tests. Acute toxicity study showed that the extract had an LD50 of >5000 mg/kg. Oral treatment with HAAD exhibited a significant decrease in the levels of AST, ALT, ALP and TB and an increase in the level of TP. The extract significantly diminished MDA levels. The activities of the antioxidant enzymes were significantly augmented in rats pretreated with HAAD 200 mg/kg. Histopathological examination demonstrated lower liver damage in HAAD-treated groups as compared to CCl4 groups.
Conclusion: Our findings indicated hepatoprotective effects of the hydro-alcoholic extract of A. dracunculus on CCl4-induced hepatic damage in rats and suggested that these effects may be produced by reducing oxidative stress.- انتشار مقاله: 30-06-1395
- نویسندگان: Vahid Zarezade,Jalal Moludi,Mostafa Mostafazadeh,Mohammad Mohammadi,Ali Veisi
- مشاهده
- جایگاه : پژوهشی
- مجله: Canon Journal of Medicine
- نوع مقاله: Journal Article
- کلمات کلیدی: Diagnosis,Acute coronary syndrome,Symptom Assessment,Diagnostic errors
- چکیده:
- چکیده انگلیسی: Introduction: Cardiovascular diseases are the leading cause of death for people worldwide. The purpose of this study was to determine the diagnostic accuracy of acute coronary syndromes assessment by emergency medicine specialists with accordance to the latest guidelines in shariatic hospital of Isfahan.
Methods: This cross-sectional study involved all consecutive patients that assessed in Emergency Department because of cardiac symptoms throughout one year (April 2017 to January 2018). The raw data were analyzed with SPSS software version 23.
Results: One hundred and seventy-five patients were included in this study. Moreover, pain radiation in the left shoulder (p-value=0.02), cold sweating (p-value=0.01), obesity (p-value=0.00), and chronic diseases (p-value=0.45) recorded more in ACS patients compared to control group. Result showed that the using of nitrate drug leads to significant reduction in pain intensity in ACS patients and make significant higher change in their electrocardiogram (ECG) in comparison to control group. Finally, results indicated that using the troponin test in the final diagnosis, ACS patients showed higher troponin levels compared to control group. Finally, results indicated that using the troponin test in the final diagnosis, ACS patients showed higher troponin levels compared to control group.
Conclusion: Patients with a final diagnosis of ACS are older than the control group. Moreover, the retrosternal pain, chest pain, exertional dyspnea, radiating pain in left shoulder or hands and cold sweating were significantly more common in patients with ACS. Based on this, the quick actions relates to ACS should be implemented to improve the diagnostic accuracy in the future.- انتشار مقاله: 01-05-1398
- نویسندگان: Zahra Karimi,Ali Torkan,Malihe Aslani,Mohammad Mohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Canon Journal of Medicine
- نوع مقاله: Journal Article
- کلمات کلیدی: cancer,Squamous Cell Carcinoma,pancreas
- چکیده:
- چکیده انگلیسی: Introduction: Adenocarcinoma is the most common malignancy in pancreas. Normally there is no squamous cell in pancreas. Pancreas Squamous Cell Carcinoma (SCC) is a rare tumor and its presentation is like adenocarcinoma and no specific symptom and sign is reported. Tumor markers are not helpful for this disease.
Case presentation: We report a 55 year-old female patient who had pancreas SCC. All investigations were normal and no other site of SCC, as a possible source for metastasis, was found. The tumor was not operable and she received 3 cycles of cisplatin and 5-fluorouracil. Then she received radiotherapy up to 44 Gy. Although she had partial response, operation was not again possible and then she received chemotherapy. Unfortunately she developed liver metastasis and passed away 9 months after diagnosis.
Conclusion: pancreas SCC is a rare tumor and the role of surgery and radiotherapy is not well studied. Chemotherapy is better to be administered according to SCC of other sites. Despite aggressive treatment, this malignant disease has a poor prognosis.- انتشار مقاله: 17-06-1398
- نویسندگان: Hamid Nasrollahi,Zahra Eskandari,Mohammad Reza Sasani,Seyed Hassan Hamedi,Reza Khellat,Mansour Ansari,Niloofar Ahmadloo,Shapour Omidvari,Mohammad Mohammadianpanah,Ahmad Mosalaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Caspian Journal of Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: HPLC,Malathion,rice,Pesticides residue,α-endosulfan,MSPD
- چکیده:
- چکیده انگلیسی: An extraction method based on matrix solid phase dispersion (MSPD) and high performance liquid chromatography with UV detection for quantification of two widely used pesticides (Malathion and α-Endosulfan) in Khazar rice from north of Iran were investigated. The ratio of solid phase (adsorbent) to sample, types of eluting solvent and its volume were optimized to achieve the highest recoveries for the analytes. Under the appropriate condition, MSPD extraction of target pesticides from rice sample was carried out through mixing of neutral alumina to rice sample in the ratio of 3:1 and elution of analytes from sample mixture using 16 ml of acetone as eluting solvent. Limit of detection, mean recoveries (n=3) and relative standard deviation for malathion and α-endosulfan were 2.31, 2.27 ppm, 99.04%, 71.70% and 0.73%, 1.89% respectively. Linear dynamic range (LDR) for malathion and -endosulfan were 7.7 – 142.2 ppm and 7.6 – 176.5 ppm, respectively. Standard addition method was used to determine the amount of pesticides residue in the marketed Khazar rice. Malathion was not detected in the marketed rice sample but the amount of α-endosulfan residue was 0.04 μg/g which is lower than the maximum residue limit (MRL) of this pesticide in rice samples.
- انتشار مقاله: 13-07-1392
- نویسندگان: Mohammad Reza Hadjmohammadi,Hosein Asri,S. Saman S.J. Nazari
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Pacific Journal of Cancer Prevention
- نوع مقاله: Journal Article
- کلمات کلیدی: VEGF,Keywords: Acute myeloid leukemia,hypoxia,HIF1α
- چکیده:
- چکیده انگلیسی: Background: Bone marrow hypoxia can promote leukemia progression in human cases of acute myeloid leukemia
(AML). In addition, low oxygen tension is able to regulate the expression of different genes involved in malignancy.
In this study, we hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF-A) genes were
assessed as principal regulators of hypoxia in do novo AML patients. Methods: Peripheral blood and bone marrow
samples were collected from 57 AML patients and 17 normal control subjects with informed consent. Expression of
HIF1α and VEGF-A was then evaluated using quantitative real-time PCR (Q-Real time PCR) and data were analyzed
with SPSS 16. Result: HIF1α and VEGF-A showed overexpression in AML patients compared to normal controls (P
AML-non M3 cases. Furthermore, there was a positive correlation between HIF1α and VEGF-A ( P 0.497). Conclusion: Adding to the many studies on the role of hypoxia in solid tumors, our data indicate that HIF1a
and VEGF-A overexpression also occurs in AML patients. We consider that this is possibly involved in leukemic cell
growth and therefore could be a promising target for clinical control.- انتشار مقاله: 20-09-1396
- نویسندگان: Mohammad Jabari,Mehdi Allahbakhshian Farsani,Sina Salari,Mohsen Hamidpour,Vahid Amiri,Mohammad Hossein Mohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Annals of Colorectal Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Pathology,Colorectal neoplasms,Clinical characteristics,Survival
- چکیده:
- چکیده انگلیسی: Context: Colorectal cancer is one of the most common cancers and the leading cause of cancer death in Iran. This study aimed to identify the clinical and pathological characteristics, as well as survival rate of colorectal cancer in Iran.
Evidence Acquisition: The articles published in PubMed without language and time restrictions were included in this review. Only original clinical articles were included in the review and non-clinical studies, including cellular, molecular, genetics, and animal reports, were excluded. The case reports, letters, reviews, and clinical reports with less than 100 patients were excluded, as well. All the clinical data regarding the patients’ demographics, tumor characteristics, and survival rate were collected.
Results: A total of 178 studies were identified at the initial step of literature search. After applying the inclusion and exclusion criteria, 27 studies, including 37901 patients were eligible. The mean age of the patients was 57.2 years, and the male-female ratio was 1.38. Colon, rectum, and rectosigmoid junction accounted for 58%, 28%, and 14% of all colorectal primary sites, respectively. Moreover, the average proportion of the patients with stages 0-I, II, III, and IV was 9%, 39%, 36%, and 16%, respectively. Besides, tumor grades 1, 2, and 3 were reported in 52%, 37%, and 11% of the patients, respectively. Adenocarcinoma (96.8%) was the most frequent histological type. The mean and median survival rate was 80.1 and 55.2 months, respectively. Additionally, the average 5-year overall survival rate was 52.5%.
Conclusions: In Iran, colorectal cancer tends to manifest at locally advanced stage with poor prognosis. Therefore, public health strategies, such as screening programs, should be planned for early detection of this aggressive neoplasm.- انتشار مقاله: 08-10-1392
- نویسندگان: Sareh Hoseini,Leila Moaddabshoar,Simin Hemati,Mohammad Mohammadianpanah
- مشاهده
- جایگاه : پژوهشی
- مجله: Applied Research on English Language
- نوع مقاله: Journal Article
- کلمات کلیدی: Computer-mediated Communication (CMC),Asynchronous Online Discussion Forum,Technology and Writing,Feedback Provision
- چکیده:
- چکیده انگلیسی: This paper focuses on the impact of an asynchronous online discussion forum on the development of students’ ability in and attitudes toward writing in English. To do this, 60 undergraduate students majoring in English were assigned to two experimental and control groups while receiving different types of feedback. Students in the experimental group were required to take part in an asynchronous forum by writing a five-paragraph essay, challenging their ideas and providing feedback based on a pre-designed feedback sheet, whereas students in the control group received traditional face-to-face feedback by the teacher. Analysis of the data obtained through a pre-test, a post-test, and a survey indicated that students’ writing improved significantly in the experimental group, on both lexis and grammar planes, as the results of engaging in replying to peers’ questions, involving in writing by exchanging feedback, and employing self-assessment strategies to revise their own work. Furthermore, they also expressed more positive attitudes toward writing. The study offers implications for L2 writing instruction in EFL contexts
- انتشار مقاله: 13-06-1397
- نویسندگان: Mohammad Omid Mohammadi,Ali Akbar Jabbari,Alimohammad Fazilatfar
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Mathematical Finance and Application
- نوع مقاله: Journal Article
- کلمات کلیدی: Data mining,Genetic Algorithm,financial reporting fraud,fraud detection
- چکیده:
- چکیده انگلیسی: both academic and auditing firms have been searching for ways to detect corporate fraud. The main objective of this study was to present a model to detect financial reporting fraud by companies listed on Tehran Stock Exchange (TSE) using genetic algorithm. For this purpose, consistent with theoretical foundations, 21 variables were selected to predict fraud in financial reporting that finally, using statistical tests, 9 variables including SALE/EMP, RECT/SALE, LT/CEQ, INVT/SALE, SALE/TA, NI/CEQ, NI/SALE, LT/XINT, and AT/LT were selected as the potential financial reporting fraud indexes. Then, using genetic algorithm, the final model of fraud detection in financial reporting was presented. The statistical population of this study included 66 companies including 33 fraudulent and 33 non-fraudulent companies from 2011 to 2016. The results showed that the presented model with the accuracy of 91.5% can detect fraudulent companies. These findings extend financial statement fraud research and can be used by practitioners and regulators to improve fraud risk models.
- انتشار مقاله: 11-04-1398
- نویسندگان: Mahmood Mohammadi,Shohreh Yazdani,Mohammadhamed Khanmohammadi
- مشاهده