در هنگام جستجو کلمه در قسمت عنوان میتوانید کلمات مورد جستجو را با کاراکتر (-) جدا کنید.
کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Zeolite,photocatalyst,TiO2,Methyl orange,MG
- چکیده:
- چکیده انگلیسی: Photodegradation of methyl orange was investigated using synthesized TiO2:Mg2+/zeolite as the photocatalyst. The photocatalyst was characterized by X-ray, XRF, FT-IR, and SEM. The photocatalytic activities of TiO2:Mg2+/zeolite samples were evaluated in the degradation of methyl orange under visible light irradiation. The appropriate content of Mg in the composite was obtained as 4.711 wt% with 100% removal of methyl orange in 50 minutes. The influence of irradiation time, catalyst concentration, pH, and calcination temperature on the photodegradation of methyl orange was investigated, and the appropriate amounts obtained for these parameters were 60 min, 5 g/l, 10, and 450 °C, respectively. The degradation of methyl orange over TiO2:Mg2+/zeolite was about 82% after five cycles, confirming the suitable reusability of the photocatalyst.
- انتشار مقاله: 08-09-1398
- نویسندگان: Afsaneh Mozayyeni,Jafar Mahmoudi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Information Technology Management
- نوع مقاله: Journal Article
- کلمات کلیدی: Corporate Governance,COBIT,IT governance
- چکیده:
- چکیده انگلیسی: Corporate governance is the system by which corporations are directed and controlled. Corporate governance also provides the structure through which company objectives are established, the means to achieve these objectives, and how to monitor their performance. ICTs have the potential to make organization and its services more transparent by providing easy access to information. This research aims to evaluate the relationship between information technology governance and corporate governance. The survey sample population consisted of 178 randomly taken managers and employees who work in public organizations. To examine the hypothesis, we use canonical correlation analysis. An important part of results from canonical correlation analysis indicated that there is a proper linear mixture between the variables of canonical effective factors on corporate governance and its components.
- انتشار مقاله: 10-09-1393
- نویسندگان: Mohammad Hossein Ronaghi,Jafar Mahmoudi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Information Technology Management
- نوع مقاله: Journal Article
- کلمات کلیدی: Enterprise Architecture (EA),Enterprise Architecture Maturity Assessment (EAMA),IT-Business Process Alignment,IT Process
- چکیده:
- چکیده انگلیسی: Today, enterprise architecture(EA) is one of the most important IT solutions for business and IT strategic alignment and also it is so supportive and effective tool for organizing and managing complicated information system in dynamic organization environment. Due to efficient enterprise architecture management the organization can obtain the EA valuable benefits. EA maturity assessment is a helpful and recognized EA management method that evaluates EA current state and demonstrates its strengths and weaknesses. Also EA maturity assessment framework (EAMAF) indicates growth path. By using the result of this method, IT mangers can easily plan to enhance EA maturity of their enterprise. In this paper, after reviewing EAMAF literature, a new EA maturity assessment framework by applying IT processes is proposed. Study on the proposed framework consists of questionnaire survey that was mailed to the EA architecture professionals. The findings show that IT processes are appropriate criteria to assess EA maturity. Finally the proposed EAMAF is validated as a verified framework.
- انتشار مقاله: 11-10-1348
- نویسندگان: Jafar Mahmoudi,Mohammad Mosakhani,Hanieh Sadat Beiryaie
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Otorhinolaryngology
- نوع مقاله: Journal Article
- کلمات کلیدی: Echocardiography,Electrocardiography,congenital heart disease,Congenital sensory-neural hearing loss
- چکیده:
- چکیده انگلیسی: Introduction:
Hearing impairment is the most frequent sensorial congenital defect in newborns and has increased to 2–4 cases per 1,000 live births. Sensory-neural hearing loss (SNHL) accounts for more than 90% of all hearing loss. This disorder is associated with other congenital disorders such as renal, skeletal, ocular, and cardiac disorders. Given that congenital heart diseases are life-threatening, we decided to study the frequency of congenital heart diseases in children with congenital sensory-neural deafness.
Materials and Methods:
All children who had undergone cochlear implantation surgery due to SNHL and who had attended our hospital for speech therapy during 2008–2011 were evaluated by Doppler echocardiography.
Results:
Thirty-one children (15 boys and 16 girls) with a mean age of 55.70 months were examined, and underwent electrocardiography (ECG) and echocardiography. None of the children had any signs of heart problems in their medical records. Most of their heart examinations were normal, one patient had expiratory wheeze, four (12%) had mid-systolic click, and four (12%) had an intensified S1 sound. In echocardiography, 15 children (46%) had mitral valve prolapse (MVP) and two (6%) had minimal mitral regurgitation (MR). Mean ejection fraction (EF) was 69% and the mean fractional shortening (FS) was 38%.
Conclusion:
This study indicates the need for echocardiography and heart examinations in children with SNHL.
- انتشار مقاله: 18-03-1394
- نویسندگان: Masoud Motasaddi Zarandy,Mohammad Jafar Mahmoudi,Iran Malekzadeh,Sevil Nasirmohtaram
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Immunology
- نوع مقاله: Journal Article
- کلمات کلیدی: ELISA,Flow cytometry,CD34,Monoclonal antibody,Western blotting
- چکیده:
- چکیده انگلیسی: Background: Human CD34 is a transmembrane glycoprotein which is expressed in human hematopoietic stem cells (HSCs) and the small- vessel endothelial cells of a variety of tissues. CD34 plays a critical role as a marker for diagnosis and classification of leukemia. Anti CD34 antibodies are used for isolation and purification of HSCs from bone marrow, peripheral blood and cord blood.
Objective: To characterize a newly produced monoclonal antibody against a human CD34 peptide.
Methods: Anti CD34 monoclonal antibody (Clone 2C10-D3) was purified from mouse ascitic fluid and hybridoma cell culture supernatants by affinity chromatography and its immune reactivity was examined by ELISA. The purified antibody was further characterized using Western blot and flow cytometry on TF1 (Human Erythroblast) cell line.
Results: ELISA experiment revealed that the antibody recognized CD34 peptide. Western blot analysis on TF1 cell lysate confirmed the reactivity of the antibody with a 42 KDa protein. Blocking the antibody with a saturating concentration of specific CD34 peptide resulted in loss of its activity with TF1 lysate in Western blot. The 2C10-D3 antibody reacted with TF1 cells in flow cytometry in a similar manner to a commercial anti CD34 monoclonal antibody.
Conclusions: Our data suggest that the anti CD34 monoclonal antibody (Clone 2C10-D3) is an appropriate antibody to study the CD34+ cells by flow cytometry and Western blot.- انتشار مقاله: 15-05-1395
- نویسندگان: Mahmood Shams,Mahmood Jeddi-Tehrani,Farzaneh Notash Haghighat,Ali Ahmad Bayat,Jafar Mahmoudian,Mohammad Reza Rezvani
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Immunology
- نوع مقاله: Journal Article
- کلمات کلیدی: Peripheral blood mononuclear cells,atherosclerosis,Cytotoxicity,oxLDL
- چکیده:
- چکیده انگلیسی: Background: Atherosclerosis, a chronic inflammatory disease of the vessel wall is characterized by local and systemic immune responses to a variety of antigens. Oxidized low-density lipoprotein (oxLDL) is considered as an important determining factor in the pathogenesis of atherosclerosis.
Objective: The purpose of this study was to investigate the degree of peripheral blood mononuclear cells (PBMC) vulnerability to in vitro oxLDL-induced cytotoxicity from atherosclerotic patients in comparison to healthy individuals.
Methods: Thirty patients with atherosclerotic lesions, confirmed by angiography, and 30 matched healthy individuals were investigated. PBMC was prepared from individuals' blood samples which were further stimulated with low dose (1 μg/mL) and high dose (50 μg/mL) of extensively oxidized LDL. MTT assay was utilized to measure cell viability and proliferation. Stimulation index (SI) was calculated as mean ratio of optical density (OD) of the stimulated cells divided by OD of untreated cells.
Results: Low dose oxLDL treatment caused no significant proliferative or cytotoxic effect in the control group; however, similar treatment caused significant cytotoxic effect in the patient group compared to the controls (p=0.026). High dose oxLDL treatment induced more significant cytotoxicity in the patient compared to the control group (p=0.006). Comparison of the SI between the two groups of patients and controls showed significantly lower index by either the low (p=0.03) or the high dose (p<0.001) oxLDL in the patients compared to the controls.
Conclusions: PBMC from patients with atherosclerosis showed increased susceptibility to oxLDL-induced cytotoxicity. Our results imply that prolonged exposure to elevated levels of circulating oxLDL could weaken the cellular defense mechanisms by progressive depletion of the pool of antiapoptotic proteins, rendering the cells more vulnerable to oxLDL-induced cell death.- انتشار مقاله: 15-05-1395
- نویسندگان: Mohammad Jafar Mahmoudi,Maryam Mahmoudi,Fereydoon Siassi,Fazel Shokri,Mohammad Reza Eshraghian,Amir Hassan Zamani,Reza Chahardoli,Mona Hedayat,Jalal Khoshnoodi,Hashem Nayeri,Nima Rezaei,Ali-Akbar Saboor-Yaraghi
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Response surface methodology,Zeolite,Keywords: Lead,Clinoptilolite,adsorption isotherms
- چکیده:
- چکیده انگلیسی: In this research, the removal of lead from the aqueous solution was investigated using natural nontoxic zeolite (clinoptilolite) as a low-cost adsorbent in order to reduce human exposure to it. The clinoptilolite zeolite obtained from the Semnan area was characterized by X-ray diffraction pattern, FTIR spectroscopy and scanning electron microscopy (SEM). The central composite design (CCD) defined under the response surface methodology (RSM) was used for designing the experiments and analyzing the sorption of lead. Three parameters of contact time (43.07-101.93 min), initial concentration (508-3006 mg/L) and temperature (20-51˚C) were applied to optimize the removal percentage of lead by zeolite. It was found that the initial concentration is the most important parameter affecting the removal percentage of lead, followed by the temperature of process. The optimum values of initial concentration, contact time and temperature were found to be 2750 ppm, 82.87 min and 65°C for 99.81% removal of lead, respectively, with a high desirability of 0.990. The adsorption data fitted the Freundlich adsorption model better than the Langmuir model, with the maximum sorption capacity of the clinoptilolite zeolite for Pb(II) equaling 136.99 (mg/g).
- انتشار مقاله: 28-10-1395
- نویسندگان: Jafar Mahmoudi,Monire Rahimi
- مشاهده