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    Highly efficient of molybdenum trioxide-cadmium titanate nanocomposites for ultraviolet light photocatalytic and antimicrobial application: Influence of reactive oxygen species

    , Article Journal of Photochemistry and Photobiology B: Biology ; Volume 191 , 2019 , Pages 75-82 ; 10111344 (ISSN) Zhu, J. M ; Hosseini, M ; Fakhri, A ; Salari Rad, S ; Hadadi, T ; Nobakht, N ; Sharif University of Technology
    Elsevier B.V  2019
    In the present work we report the enhanced UV light photocatalytic performance of cadmium titanate photocatalyst by MoO 3 for Drug pollutant degradation. The nano photocatalyst sample was synthesized employing the Pechini-ultrasonic-hydrothermal route. Therefore, the nano photocatalyst were characterized by various analytical devices. The wide scan X-ray photoelectron spectral study confirmed the MoO 3 in the CdTiO 3 matrix. The crystallite size calculated with the Debye-Scherrer equation (55.4, 57.0, 61.2 and 63.1 nm for pure CdTiO 3 , MoCdTi-0, MoCdTi-1, and MoCdTi-2 nanocomposites, respectively). SEM micrographs revealed nanowire morphology indicated the crystalline nature of the sample.... 

    Unexpected optical limiting properties from MoS2 nanosheets modified by a semiconductive polymer

    , Article Chemical Communications ; Volume 51, Issue 61 , Jun , 2015 , Pages 12262-12265 ; 13597345 (ISSN) Zhao, M ; Chang, M. J ; Wang, Q ; Zhu, Z. T ; Zhai, X. P ; Zirak, M ; Moshfegh, A. Z ; Song, Y. L ; Zhang, H. L ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Direct solvent exfoliation of bulk MoS2 with the assistance of poly(3-hexylthiophene) (P3HT) produces a novel two-dimensional organic/inorganic semiconductor hetero-junction. The obtained P3HT-MoS2 nanohybrid exhibits unexpected optical limiting properties in contrast to the saturated absorption behavior of both P3HT and MoS2, showing potential in future photoelectric applications  

    Quantitative in vivo microsampling for pharmacokinetic studies based on an integrated solid-phase microextraction system

    , Article Analytical Chemistry ; Volume 79, Issue 12 , 2007 , Pages 4507-4513 ; 00032700 (ISSN) Zhang, X ; Eshaghi, A ; Musteata, F. M ; Ouyang, G ; Pawliszyn, J ; Sharif University of Technology
    An integrated microsampling approach based on solid-phase microextraction (SPME) was developed to provide a complete solution to highly efficient and accurate pharmacokinetic studies. The microsampling system included SPME probes that are made of poly(ethylene glycol) (PEG) and C18-bonded silica, a fast and efficient sampling strategy with accurate kinetic calibration, and a high-throughput desorption device based on a modified 96-well plate. The sampling system greatly improved the quantitative capability of SPME in two ways. First, the use of the C18-bonded silica/PEG fibers minimized the competition effect from analogues of the target analytes in a complicated sample matrix such as blood... 

    Generic extraction medium: From highly polar to non-polar simultaneous determination

    , Article Analytica Chimica Acta ; Volume 1066 , 2019 , Pages 1-12 ; 00032670 (ISSN) Zeinali, S ; Khalilzadeh, M ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2019
    Sample preparation for non-target analysis is challenging due to the difficulty in the extraction of polar and non-polar analytes simultaneously. Most commercial solid sorbents lack the proper comprehensiveness for extraction of analytes with different physiochemical properties. A possible key is the combination of hydrophobic polymer and hydrophilic surface functional groups in solid based extraction methods in order to generate the susceptibility for retaining both polar and non-polar analytes. To pursue this goal, in this study, four polar groups including [sbnd]NH 2 , [sbnd]NO 2 , [sbnd]COOH, and [sbnd]COCH 3 were chemically bound to Amberlite XAD-4 substrate in order to prepare a... 

    Characterization of a moderate thermophilic Nocardia species able to grow on polycyclic aromatic hydrocarbons

    , Article Letters in Applied Microbiology ; Volume 45, Issue 6 , December , 2007 , Pages 622-628 ; 02668254 (ISSN) Zeinali, M ; Vossoughi, M ; Ardestani, S. K ; Sharif University of Technology
    Aims: Our goal was the characterization of a new moderate thermophilic polycyclic aromatic hydrocarbon (PAH)-utilizing Nocardia strain. Methods and Results: A thermophilic bacterium, strain TSH1, was isolated from a contaminated soil. The macroscopic and microscopic features fit well with the description of Nocardia species. The results of 16S rRNA gene analysis showed 100% match to the type strain of N. otitidiscaviarum DSM 43242T. Strain TSH1 showed the same mycolic acid pattern as the type strain of N. otitidiscaviarum but its fatty acid profile did not permit identification to the species level. The carbon utilization profile of strain TSH1 was different from N. otitidiscaviarum. The... 

    Joint approximate diagonalization of eigenmatrices as a high-throughput approach for analysis of hyphenated and comprehensive two-dimensional gas chromatographic data

    , Article Journal of Chromatography A ; Volume 1524 , 2017 , Pages 188-201 ; 00219673 (ISSN) Zarghani, M ; Parastar, H ; Sharif University of Technology
    The objective of the present work is development of joint approximate diagonalization of eigenmatrices (JADE) as a member of independent component analysis (ICA) family, for the analysis of gas chromatography-mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC–MS) data to address incomplete separation problem occurred during the analysis of complex sample matrices. In this regard, simulated GC–MS and GC × GC–MS data sets with different number of components, different degree of overlap and noise were evaluated. In the case of simultaneous analysis of multiple samples, column-wise augmentation for GC–MS and column-wise super-augmentation... 

    Novel class detection in data streams using local patterns and neighborhood graph

    , Article Neurocomputing ; Volume 158 , June , 2015 , Pages 234-245 ; 09252312 (ISSN) ZareMoodi, P ; Beigy, H ; Kamali Siahroudi, S ; Sharif University of Technology
    Elsevier  2015
    Data stream classification is one of the most challenging areas in the machine learning. In this paper, we focus on three major challenges namely infinite length, concept-drift and concept-evolution. Infinite length causes the inability to store all instances. Concept-drift is the change in the underlying concept and occurs in almost every data stream. Concept-evolution, in fact, is the arrival of novel classes and is an undeniable phenomenon in most real world data streams. There are lots of researches about data stream classification, but most of them focus on the first two challenges and ignore the last one. In this paper, we propose new method based on ensembles whose classifiers use... 

    Introducing a comprehensive framework to measure spike-LFP coupling

    , Article Frontiers in Computational Neuroscience ; Volume 12 , 2018 ; 16625188 (ISSN) Zarei, M ; Jahed, M ; Daliri, M. R ; Sharif University of Technology
    Frontiers Media S.A  2018
    Measuring the coupling of single neuron's spiking activities to the local field potentials (LFPs) is a method to investigate neuronal synchronization. The most important synchronization measures are phase locking value (PLV), spike field coherence (SFC), pairwise phase consistency (PPC), and spike-triggered correlation matrix synchronization (SCMS). Synchronization is generally quantified using the PLV and SFC. PLV and SFC methods are either biased on the spike rates or the number of trials. To resolve these problems the PPC measure has been introduced. However, there are some shortcomings associated with the PPC measure which is unbiased only for very high spike rates. However evaluating... 

    Online analysis of local field potentials for seizure detection in freely moving rats

    , Article Iranian Journal of Basic Medical Sciences ; Volume 23, Issue 2 , 2020 , Pages 173-177 Zare, M ; Nazari, M ; Shojaei, A ; Raoufy, M. R ; Mirnajafi Zadeh, J ; Sharif University of Technology
    Mashhad University of Medical Sciences  2020
    Objective(s): Seizure detection during online recording of electrophysiological parameters is very important in epileptic patients. In the present study, online analysis of field potential recordings was used for detecting spontaneous seizures in epileptic animals. Materials and Methods: Epilepsy was induced in rats by pilocarpine injection. During the chronic period of the pilocarpine model, local field potential (LFP) recording was run for at least 24 hr. At the same time, video monitoring of the animals was done to determine the real time of seizure occurrence. Both power and sample entropy of LFP were used for online analysis. Results: Obtained results showed that changes in LFP power... 

    Determining of the optimized dimensions of the Marinelli beaker containing source with inhomogeneous emission rate by using genetic algorithm coupled with MCNP and determining distribution type by neural networks

    , Article Applied Radiation and Isotopes ; Volume 157 , 2020 Zamzamian, S. M ; Hosseini, S. A ; Feghhi, S. A ; Samadfam, M ; Sharif University of Technology
    Elsevier Ltd  2020
    In order to determine the activity of C137s in soil resulting from nuclear accidents or fallouts, the best choice is to use HPGe detectors due to their best energy resolutions. In this regard, in order to enhance the detection efficiency, the Marinelli beakers have been used to increase the radiation interaction with the sensitive volume of the detector. In previous works, to optimize the dimension of Marinelli beakers, the assumption was that the emission rate of the source is homogeneous in beaker volume. In the present study, to investigate the effect of the inhomogeneous emission rate of the source on the optimum dimensions of the beaker, in a simple case, the beaker was divided into two... 

    AntAngioCOOL: computational detection of anti-angiogenic peptides

    , Article Journal of Translational Medicine ; Volume 17, Issue 1 , 2019 ; 14795876 (ISSN) Zahiri, J ; Khorsand, B ; Yousefi, A. A ; Kargar, M. J ; Shirali Hossein Zade, R ; Mahdevar, G ; Sharif University of Technology
    BioMed Central Ltd  2019
    Background: Angiogenesis inhibition research is a cutting edge area in angiogenesis-dependent disease therapy, especially in cancer therapy. Recently, studies on anti-angiogenic peptides have provided promising results in the field of cancer treatment. Methods: A non-redundant dataset of 135 anti-angiogenic peptides (positive instances) and 135 non anti-angiogenic peptides (negative instances) was used in this study. Also, 20% of each class were selected to construct an independent test dataset (see Additional files 1, 2). We proposed an effective machine learning based R package (AntAngioCOOL) to predict anti-angiogenic peptides. We have examined more than 200 different classifiers to build... 

    Experimental feasibility study of estimation of the normalized central blood pressure waveform from radial photoplethysmogram

    , Article Journal of Healthcare Engineering ; Volume 6, Issue 1 , 2015 , Pages 121-144 ; 20402295 (ISSN) Zahedi, E ; Sohani, V ; Mohd. Ali, M. A ; Chellappan, K ; Beng, G. K ; Sharif University of Technology
    Multi-Science Publishing Co. Ltd  2015
    The feasibility of a novel system to reliably estimate the normalized central blood pressure (CBPN) from the radial photoplethysmogram (PPG) is investigated. Right-wrist radial blood pressure and left-wrist PPG were simultaneously recorded in five different days. An industry-standard applanation tonometer was employed for recording radial blood pressure. The CBP waveform was amplitude-normalized to determine CBPN. A total of fifteen second-order autoregressive models with exogenous input were investigated using system identification techniques. Among these 15 models, the model producing the lowest coefficient of variation (CV) of the fitness during the five days was... 

    Fabrication and characterization of core-shell electrospun fibrous mats containing medicinal herbs for wound healing and skin tissue engineering

    , Article Marine Drugs ; Volume 17, Issue 1 , 2019 ; 16603397 (ISSN) Zahedi, E ; Esmaeili, A ; Eslahi, N ; Shokrgozar, M. A ; Simchi, A ; Sharif University of Technology
    MDPI AG  2019
    Nanofibrous structures mimicking the native extracellular matrix have attracted considerable attention for biomedical applications. The present study aims to design and produce drug-eluting core-shell fibrous scaffolds for wound healing and skin tissue engineering. Aloe vera extracts were encapsulated inside polymer fibers containing chitosan, polycaprolactone, and keratin using the co-axial electrospinning technique. Electron microscopic studies show that continuous and uniform fibers with an average diameter of 209 ± 47 nm were successfully fabricated. The fibers have a core-shell structure with a shell thickness of about 90 nm, as confirmed by transmission electron microscopy. By... 

    Finger photoplethysmogram pulse amplitude changes induced by flow-mediated dilation

    , Article Physiological Measurement ; Volume 29, Issue 5 , 2008 , Pages 625-637 ; 09673334 (ISSN) Zahedi, E ; Jaafar, R ; Mohd Ali, M. A ; Mohamed, A. L ; Maskon, O ; Sharif University of Technology
    This study was conducted to investigate the utility and efficacy of finger photoplethysmogram pulse amplitude (PPG-AC) in comparison with the standard Doppler ultrasound in assessing an endothelial function via flow-mediated dilation (FMD). High-resolution B-mode scanning of the right brachial artery (BA) of 31 healthy subjects aged 39.7 ± 11.3 (range 22-64) years and 52 risk subjects aged 47.7 ± 10.8 (range 30-65) years were performed before and after 4 min of upper arm occlusion. Concurrent with the ultrasound measurement (where color Doppler imaging was used to enhance arterial boundary detection), PPG signals were recorded from both index fingers for cross evaluation and comparison. Our... 

    Analysis of the effect of ageing on rising edge characteristics of the photoplethysmogram using a modified windkessel model

    , Article Cardiovascular Engineering ; Volume 7, Issue 4 , 2007 , Pages 172-181 ; 15678822 (ISSN) Zahedi, E ; Chellappan, K ; Mohd Ali, M. A ; Singh, H ; Sharif University of Technology
    Ageing is one of the main contributing factors towards increasing arterial stiffness, leading to changes in peripheral pulses propagation. Therefore the characteristics of the photoplethysmogram (PPG) pulse, especially the rising edge and peak position, are greatly affected. In this study, the PPG pulse rising edge and corresponding peak position have been investigated non-invasively in human subjects as a function of age. Fifteen healthy subjects were selected and grouped in five age intervals, from 20 to 59 years, based on their comparable systolic-diastolic blood pressure and PPG amplitude. As expected, the peripheral pulse shows a steep rise and early peak in younger subjects. With age,... 

    Type V collagen in scar tissue regulates the size of scar after heart injury

    , Article Cell ; Volume 182, Issue 3 , 2020 , Pages 545-562.e23 Yokota, T ; McCourt, J ; Ma, F ; Ren, S ; Li, S ; Kim, T. H ; Kurmangaliyev, Y. Z ; Nasiri, R ; Ahadian, S ; Nguyen, T ; Tan, X. H. M ; Zhou, Y ; Wu, R ; Rodriguez, A ; Cohn, W ; Wang, Y ; Whitelegge, J ; Ryazantsev, S ; Khademhosseini, A ; Teitell, M. A ; Chiou, P. Y ; Birk, D. E ; Rowat, A. C ; Crosbie, R. H ; Pellegrini, M ; Seldin, M ; Lusis, A. J ; Deb, A ; Sharif University of Technology
    Cell Press  2020
    Scar tissue size following myocardial infarction is an independent predictor of cardiovascular outcomes, yet little is known about factors regulating scar size. We demonstrate that collagen V, a minor constituent of heart scars, regulates the size of heart scars after ischemic injury. Depletion of collagen V led to a paradoxical increase in post-infarction scar size with worsening of heart function. A systems genetics approach across 100 in-bred strains of mice demonstrated that collagen V is a critical driver of postinjury heart function. We show that collagen V deficiency alters the mechanical properties of scar tissue, and altered reciprocal feedback between matrix and cells induces... 

    Cross-flow microfiltration of rough non-alcoholic beer and diluted malt extract with tubular ceramic membranes: Investigation of fouling mechanisms

    , Article Journal of Membrane Science ; Volume 362, Issue 1-2 , 2010 , Pages 306-316 ; 03767388 (ISSN) Yazdanshenas, M ; Soltanieh, M ; Tabatabaei Nejad, S. A. R ; Fillaudeau, L ; Sharif University of Technology
    The clarification of rough non-alcoholic beer (RNAB) and diluted malt extract (DME) was investigated in a pilot plant consisting of a tubular ceramic membrane with nominal pore diameter of 0.45μm. The results of the primary experiments show that the concentration of suspended particles in the RNAB (∼0.05kg/m3) and DME (∼0.2kg/m3) correlates proportionally to turbidity (in NTU) with the factor of 4.45×10-4 (kgm-3NTU-1). During cross-flow microfiltration (CFMF), flux declined drastically with time due to fouling mechanisms and propensity. According to the characterizing curve of log(d2t/dV2) versus log(dt/dV), fouling is initiated by penetration of aggregates through the membrane surface,... 

    Expression of functional recombinant human tissue transglutaminase (TG2) using the bac-to-bac baculovirus expression system

    , Article Advanced Pharmaceutical Bulletin ; Volume 6, Issue 1 , 2016 , Pages 49-56 ; 22285881 (ISSN) Yazdani, Y ; Azari, S ; Kalhor, H. R ; Sharif University of Technology
    Tabriz University of Medical Sciences 
    Tissue transglutaminase (TG2) is a unique multifunctional enzyme. The enzyme possesses enzymatic activities such as transamidation/crosslinking and non-enzymatic functions such as cell migration and signal transduction. TG2 has been shown to be involved in molecular mechanisms of cancers and several neurodegenerative diseases such as Alzheimer's disease. The present study aimed at cloning and expression of full length human TG2 in Bac-to-Bac baculovirus expression system and evaluation of its activity. Methods: pFastBac HTA donor vector containing coding sequence of human TG2 was constructed. The construct was transformed to DH10Bac for generating recombinant bacmid. The verified bacmid was... 

    A study of Acidithiobacillus Ferrooxidans DSMZ 583 Adaptation to Heavy Metals

    , Article Iranian Journal of Biotechnology ; Volume 9, Issue 2 , 2011 , Pages 133-144 ; 17283043 (ISSN) Yaghmaei, S ; Ghobadi, Z ; Sharif University of Technology
    In this study the ability of Acidithiobacillus ferrooxi-dans, with regard to the biorecovery of heavy metals in shake flask has been investigated. Adaptation experiments with the single metal ions Ni, Co, V, Mo, W and a mixture of the first four metal ions in the medium was developed through serial sub-culturing. Adaptation showed that A. ferrooxidans could tolerate up to 2.3 g/l Ni, 1.4 g/l Co, 1.4 g/l V, 0.045 g/l Mo and 0.005 g/l W, singly. In the presence of multi-metals considering a mixture of Ni-Co-V-Mo, the bacteria was able to tolerate up to 1.5 g/l Ni, 0.8 g/l Co, 0.8 g/l V and 0.05 g/l Mo in steps of 50-100 mg/l for Ni, Co and V, while for Mo and W with increments in concentration... 

    Bottom-up synthesis of nitrogen and oxygen co-decorated carbon quantum dots with enhanced DNA plasmid expression

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 184 , 2019 ; 09277765 (ISSN) Yadegari, A ; Khezri, J ; Esfandiari, S ; Mahdavi, H ; Karkhane, A. A ; Rahighi, R ; Heidarimoghadam, R ; Tayebi, L ; Hashemi, E ; Farmany, A ; Sharif University of Technology
    Elsevier B.V  2019
    In this paper, a bottom-up hydrothermal route is reported for the synthesis of oxygen and nitrogen co-decorated carbon quantum dots (CQDs) using ammonium hydrogen citrate (AHC) as a single precursor. DLS data approved the formation of 4.0 nm (average size) CQDs. XRD pattern shows the interlayer spacing (002) of 3.5 Å for CQDs, which is exactly the same as that of crystalline graphite. XPS and FTIR spectra verified the formation of oxygen and nitrogen functional groups on the CQDs surface. Co-decorated carboxyl, hydroxyl and amine groups on the CQDs surfaces make them as promising polyelectrolyte for gene delivery. Toxicity assay showed a survival rate of 70% under different incubation times...