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Norouzian S.,Iran University of Science and Technology | Norouzian S.,K. N. Toosi University of Technology | Larijani M.M.,Medical and Industrial Research School | Afzalzadeh R.,K. N. Toosi University of Technology
Bulletin of Materials Science

In this study, zirconium nitride thin films were deposited on Si substrates by ion beam sputtering (IBS). Influence of N2/(N2+Ar) on the structural and physical properties of the films has been investigated with respect to the atomic ratio between nitrogen and zirconium. It was found that the thickness of layers decreased by increasing the F(N2). Moreover, crystalline plane peaks such as (111), (200) and (220) with (111) preferred orientation were observed due to strain energy which associate with (111) orientation in ZrN. Also, the fluctuation in nitrogen flow ratio results in colour and electrical resistivity of films. © Indian Academy of Sciences. Source

Fazaeli Y.,Shahid Beheshti University | Amini M.M.,Shahid Beheshti University | Mohajerani E.,Shahid Beheshti University | Sharbatdaran M.,Medical and Industrial Research School | Torabi N.,Shahid Beheshti University
Journal of Colloid and Interface Science

Fluorescent materials (Q)3-n(2-BuO)nAl (Q=8-hydroxyquinoline, 2-methyl-8-hydroxyquinoline and 5-chloro-8-hydroxyquinoline, n=1 or n=2) were prepared in toluene by reacting aluminum 2-butoxide with 8-hydroxyquinoline and its derivatives. The compounds were characterized by 1H, 13C and 27Al NMR in solution, and the coordination status of the aluminum atom in the complexes were determined by 27Al NMR chemical shifts. The compounds were grafted on mesoporous silica (MCM-41) at room temperature without isolation of the complexes. The prepared materials were characterized by elemental analysis, FT-IR spectroscopy, low-angle X-ray diffraction (XRD), thermal analysis (TGA/DSC) and N2 adsorption and desorption measurements. The results showed that the characteristic mesoporous structure of MCM-41 after grafting aluminum complexes remains intact. The photoluminescence (PL) properties of (Q)3-n(2-BuO)n-1@Al-MCM-41 were investigated. The results revealed that the maximum wavelength is modulated by the MCM-41 guest. © 2010 Elsevier Inc. Source

Aslian H.,Islamic Azad University at Tehran | Sadeghi M.,Medical and Industrial Research School | Mahdavi S.R.,Tehran University of Medical Sciences | Babapour Mofrad F.,Islamic Azad University at Tehran | And 3 more authors.
International Journal of Radiation Oncology Biology Physics

Purpose: To evaluate the clinical application of a robust semiautomatic image segmentation method to determine the brain target volumes in radiation therapy treatment planning. Methods and Materials: A local robust region-based algorithm was used on MRI brain images to study the clinical target volume (CTV) of several patients. First, 3 oncologists delineated CTVs of 10 patients manually, and the process time for each patient was calculated. The averages of the oncologists' contours were evaluated and considered as reference contours. Then, to determine the CTV through the semiautomatic method, a fourth oncologist who was blind to all manual contours selected 4-8 points around the edema and defined the initial contour. The time to obtain the final contour was calculated again for each patient. Manual and semiautomatic segmentation were compared using 3 different metric criteria: Dice coefficient, Hausdorff distance, and mean absolute distance. A comparison also was performed between volumes obtained from semiautomatic and manual methods. Results: Manual delineation processing time of tumors for each patient was dependent on its size and complexity and had a mean (±SD) of 12.33 ± 2.47 minutes, whereas it was 3.254 ± 1.7507 minutes for the semiautomatic method. Means of Dice coefficient, Hausdorff distance, and mean absolute distance between manual contours were 0.84 ± 0.02, 2.05 ± 0.66 cm, and 0.78 ± 0.15 cm, and they were 0.82 ± 0.03, 1.91 ± 0.65 cm, and 0.7 ± 0.22 cm between manual and semiautomatic contours, respectively. Moreover, the mean volume ratio (=semiautomatic/manual) calculated for all samples was 0.87. Conclusions: Given the deformability of this method, the results showed reasonable accuracy and similarity to the results of manual contouring by the oncologists. This study shows that the localized region-based algorithms can have great ability in determining the CTV and can be appropriate alternatives for manual approaches in brain cancer. © 2013 Elsevier Inc. Source

Grouh M.S.H.,University of Tehran | Vahdati K.,Iranian Seed and Plant Improvement Institute | Lotfi M.,University of Tehran | Hassani D.,Iranian Seed and Plant Improvement Institute | Biranvand N.P.,Medical and Industrial Research School
Journal of the American Society for Horticultural Science

We report the first successful regeneration of haploid lines in persian walnut (Juglans regia) developed by in situ parthenogenesis followed by embryo rescue. Female flowers of cultivars Hartley and Pedro and two native Iranian selections (Z63 and Z67) were pollinated using pollen of selections Z53 and Z30 that had been irradiated with gamma rays at five doses (50, 150, 300, 600, and 900 Gy). Gamma-irradiated pollen induced fruit set and development of some parthenogenetic embryos. The immature embryos were excised 30 and 45 days after pollination, cultured in vitro, and then stratified for 30 days at 4 °C to overcome dormancy. Ploidy level of the resulting plantlets was determined by chromosome counting and flow cytometry. Haploid plants were obtained from 'Hartley', 'Pedro', Z63, and Z67 after pollination using pollen irradiated at 300 and 600 Gy. Plants obtained from pollen irradiated at 50 and 150 Gy were all diploid. Molecular marker analysis using four simple sequence repeat (SSR) markers also showed that all the diploid plants recovered were zygotic and no spontaneous double haploid plants were obtained in this work. Also, the haploid plantlets presented only one allele of their female parents. These profiles confirmed the parthenogenetic origin of the obtained haploid plants. The techniques used to induce haploid walnut plants by irradiated pollen were successful and could be used in breeding programs and accelerate genome analysis in this plant in which the genome size is approximately three times the size of the human genome. Source

Chakoli A.N.,Harbin Institute of Technology | Chakoli A.N.,Medical and Industrial Research School | He J.,Harbin Institute of Technology | Cheng W.,Harbin Institute of Technology | Huang Y.,Harbin Institute of Technology
RSC Advances

Oxidized Regenerated Cellulose (ORC) has been modified by incorporating aminated MWCNTs (MWCNT-NH2)s. The pristine MWCNTs (pMWCNTs) were aminated which introduced aromatic amine groups on the side walls of the MWCNTs. For modification of neat ORC, the MWCNT-NH2s were reacted with neat ORC. To explore the origin of this behavior, amination of MWCNTs, dispersion of MWCNT-NH2s in the ORC matrix and their interfacial interactions were investigated by SEM, FT-IR and XPS. The analytical results show that during functionalization of the MWCNTs, the amine groups grafted onto the surface of the MWCNTs. In addition, the FT-IR and XPS results revealed that a relatively strong interaction existed between the aminated MWCNTs and the ORC macromolecules. The hydrophilicity test results revealed a significant increment in water uptake of the MWCNT-NH2s/ORC composites with increasing concentration of MWCNT-NH2s in the composites. The haemostatic evaluation of the MWCNT-NH2s/ORC composites in rabbits shows that the aminated MWCNTs increase the rate of blood stopping and hence decrease the blood loss from injured sites. This journal is © the Partner Organisations 2014. Source

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