Loading...
Search for:
reproducibility
0.008 seconds
Total 174 records
Membrane protected conductive polymer as micro-SPE device for the determination of triazine herbicides in aquatic media
, Article Journal of Separation Science ; Volume 33, Issue 8 , 2010 , Pages 1132-1138 ; 16159306 (ISSN) ; Khalilian, F ; Naderi, M ; Babanezhad, E ; Sharif University of Technology
Abstract
A micro-SPE technique was developed by fabricating a rather small package including a polypropylene membrane shield containing the appropriate sorbent. The package was used for the extraction of some triazine herbicides from aqueous samples. Solvent desorption was subsequently performed in a microvial and an aliquot of extractant was injected into GC-MS. Various sorbents including aniline-ortho-phenylene diamine copolymer, newly synthesized, polypyrrole, multiwall carbon nanotube, C18 and charcoal were examined as extracting media. Among them, conductive polymers exhibited better performance. Influential parameters including extraction and desorption time, desorption solvent and the ionic...
Reliability and validity of the persian version of the scoliosis research society-22r questionnaire
, Article Spine ; Volume 35, Issue 7 , 2010 , Pages 784-789 ; 03622436 (ISSN) ; Mobini, B ; Mehdian, H ; Akbarnia, B ; Bouzari, B ; Askary Ashtiani, A ; Montazeri, A ; Parnianpour, M ; Sharif University of Technology
2010
Abstract
STUDY DESIGN.: Cross-sectional validation study to investigate psychometric properties of adapted Persian version of the Scoliosis Research Society-22r (SRS-22r) questionnaire. OBJECTIVES.: To translate the SRS-22r into Persian and to evaluate the internal consistency, reliability, and validity of the Persian SRS-22r. SUMMARY OF BACKGROUND DATA.: The SRS-22r has not been translated and validated for Persian-speaking patients with idiopathic scoliosis. This was to provide a validated instrument to measure health-related quality of life in patients with idiopathic scoliosis in Iran. METHODS.: The translation and cultural adaptation of the original questionnaire were carried out in accordance...
Reliability and validity of the Foot and Ankle Outcome Score: A validation study from Iran
, Article Clinical Rheumatology ; Volume 29, Issue 5 , 2010 , Pages 479-486 ; 07703198 (ISSN) ; Mazaheri, M ; Salavati, M ; Sohani, S. M ; Askari, M ; Fanian, H ; Parnianpour, M ; Sharif University of Technology
2010
Abstract
The aims of this study were to culturally adapt and validate the Persian version of Foot and Ankle Outcome Score (FAOS) and present data on its psychometric properties for patients with different foot and ankle problems. The Persian version of FAOS was developed after a standard forward-backward translation and cultural adaptation process. The sample included 93 patients with foot and ankle disorders who were asked to complete two questionnaires: FAOS and Short-Form 36 Health Survey (SF-36). To determine test-retest reliability, 60 randomly chosen patients completed the FAOS again 2 to 6 days after the first administration. Test-retest reliability and internal consistency were assessed using...
Simultaneous voltammetric determination of ascorbic acid, acetaminophen and isoniazid using thionine immobilized multi-walled carbon nanotube modified carbon paste electrode
, Article Electrochimica Acta ; Volume 55, Issue 3 , 2010 , Pages 666-672 ; 00134686 (ISSN) ; Asadian, E ; Sharif University of Technology
2010
Abstract
A carbon paste electrode (CPE) modified with thionine immobilized on multi-walled carbon nanotube (MWCNT), was prepared for simultaneous determination of ascorbic acid (AA) and acetaminophen (AC) in the presence of isoniazid (INZ). The electrochemical response characteristics of the modified electrode toward AA, AC and INZ were investigated by cyclic and differential pulse voltammetry (CV and DPV). The results showed an efficient catalytic role for the electro-oxidation of AA and AC, leading to a remarkable peak resolution (∼303 mV) for two compounds. On the other hand, the presence of INZ, which is considered as important drug interference for AC, does not affect the voltammetric responses...
Application of carbon nanoparticle/chitosan modified electrode for the square-wave adsorptive anodic striping voltammetric determination of Niclosamide
, Article Electrochemistry Communications ; Volume 12, Issue 1 , 2010 , Pages 66-69 ; 13882481 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
2010
Abstract
A new modified electrode formed by carbon nanoparticle/chitosan film (CNP/CS) was used for electrocatalytic reduction of Niclosamide (NA). The electrochemical behavior of NA at the CNP/CS modified electrode was investigated in detail by the means of cyclic voltammetry. The reduction mechanism of NA, corresponds to the redox chemistry of nitro group, was thoroughly investigated. The effect of the experimental parameters e.g. potential and time of accumulation, pH of the buffered solutions and potential sweep rate on the response of the electrode was studied. The prepared electrode showed high stability and uniformity in the composite film, short response time, good reproducibility and an...
A metal organic framework-polyaniline nanocomposite as a fiber coating for solid phase microextraction
, Article Journal of Chromatography A ; Volume 1431 , 2016 , Pages 27-35 ; 00219673 (ISSN) ; Javanmardi, H ; Abbasi, A ; Banihashemi, S ; Sharif University of Technology
Elsevier B. V
Abstract
A metal organic framework-polyaniline (MOF/PANI) nanocomposite was electrodeposited on a stainless steel wire and used as a solid phase microextraction (SPME) fiber coating. The electropolymerization process was carried out under a constant deposition potential and applied to the corresponding aqueous electrolyte containing aniline and MOF particles. The employment of MOFs with their large and small cages and 3-D structures in synthesizing a nanocomposite was assumed to be efficient constitutes to induce more non-smooth and porous structures, approved by scanning electron microscopy (SEM) images. Three different MOFs were incorporated to synthesize the desired nanocomposites and the...
Au-Pd bimetallic nanoparticle electrodes for direct electroreduction of hexavalent chromium complexes
, Article Australian Journal of Chemistry ; Volume 69, Issue 4 , 2016 , Pages 423-430 ; 00049425 (ISSN) ; Hariri, M. B ; Kushwaha, A ; Dolati, A ; Ghorbani, M ; Goh, G. K. L ; Sharif University of Technology
CSIRO
2016
Abstract
This paper reports a simple, low-cost, and effective electrochemical technique for sensing and reducing CrVI based on a Au-Pd bimetallic nanoparticle (BNP)-decorated indium tin oxide (ITO) conducting glass electrode. It was observed that the Au-Pd BNP-decorated ITO electrode could significantly boost the electrochemical reduction of CrVI when compared with either Au nanoparticle- or Pd nanoparticle-decorated ITO electrodes. These BNP-decorated electrodes exhibited a wide linear concentration range of 0.001-100 μM, a very low detection limit (signal-to-noise ratio = 3) of 0.3 nM, and a high sensitivity of 1.701 μA μM-1. From electrochemical impedance spectroscopy, it was revealed that this...
A robust keypoint extraction and matching algorithm based on wavelet transform and information theory for point-based registration in endoscopic sinus cavity data
, Article Signal, Image and Video Processing ; Volume 10, Issue 5 , 2016 , Pages 983-991 ; 18631703 (ISSN) ; Ahmadian, A ; Kasaei, S ; Sadrehosseini, S. M ; Farnia, P ; Sharif University of Technology
Springer-Verlag London Ltd
2016
Abstract
Feature extraction is one of the most important steps in processing endoscopic data. The extracted features should be invariant to image scale and rotation to provide a robust matching across a substantial range of affine distortions and changes in 3D space. In this study, a method is proposed on the basis of the dual-tree complex wavelet transform. First, a map is estimated for each scale, and then a Gaussian weighted additive function (GWAF) is determined. Keypoints are selected from local peaks of GWAF. The matching and registration are performed by applying normalized mutual information and our modified iterative closest point. Results are reported in terms of robustness to rotation,...
Visual acuity classification using single trial visual evoked potentials
, Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 ; 2009 , Pages 982-985 ; 1557170X (ISSN) ; Shamsollahi, M. B ; Abootalebi, V ; Sharif University of Technology
Abstract
Several researches have been done to identify visual system characteristics. Some of them are based on the processing of the brain signal recordings. Visual evoked potentials (VEPs) are electrical signals which are produced in response to the visual stimuli and recorded by means of electrodes placed on the head. These signals are usually characterized by the amplitude and latency of their peaks. Different types of visual stimuli and visual system characteristics can affect the shape and hence the characteristics of VEPs. In this paper, proper visual stimuli were used and VEPs were recorded in order to classify visual acuity. To achieve this goal, visual evoked potentials were recorded and...
ECG denoising using modulus maxima of wavelet transform
, Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 ; 2009 , Pages 416-419 ; 1557170X (ISSN) ; Shamsollahi, M. B ; Mozaffari, B ; Kharabian, S ; Sharif University of Technology
Abstract
ECG denoising has always been an important issue in medical engineering. The purposes of denoising are reducing noise level and improving signal to noise ratio (SNR) without distorting the signal. This paper proposes a method for removing white Gaussian noise from ECG signals. The concepts of singularity and local maxima of the wavelet transform modulus were used for analyzing singularity and reconstructing the ECG signal. Adaptive thresholding was used to remove white Gaussian noise modulus maximum of wavelet transform and then reconstruct the signal
Fetal R-wave detection from multichannel abdominal ECG recordings in low SNR
, Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 ; 2009 , Pages 344-347 ; 1557170X (ISSN) ; Shamsollahi, M. B ; Sameni, R ; Sharif University of Technology
Abstract
Abdominal recordings of fetal ECG (fECG) have lower signal-to-noise ratio (SNR) as compared with invasive procedures. In this paper we have combined two previously proposed methods, one for extracting fECG, called piCA and the other, a transformation based on Hilbert transform to enhance the R-peaks. The combination of these methods seems to work well in situations of noisy data and fetal repositioning. Also a comparison is done by using ICA in order to extract the fetal signals. Performance of both methods is studied separately. Results show that applying the transformation on the components extracted with the use of piCA (after maternal ECG cancellation), had a very good performance. Also,...
MEG based classification of wrist movement
, Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 ; 2009 , Pages 986-989 ; 1557170X (ISSN) ; 978-142443296-7 (ISBN) ; Shamsollahi, M. B ; Hajipour, S ; Sharif University of Technology
Abstract
Neural activity is very important source for data mining and can be used as a control signal for brain-computer interfaces (BCIs). Particularly, Magnetic signals of neurons are enriched with information about the movement of different part of the body such as wrist movement. In this paper, we use MEG (Magneto encephalography) signals of two subjects recorded during wrist movement task in four directions. Data were prepared for BCI competition 2008 for multiclass classification. Our approach for this classification problem consists of PCA as a noise reduction method, ULDA for feature reduction and various linear classifiers such as Bayesian, KNN and SVM. Final results (58%-62% for subject 1...
Vibration Analysis of FGM Beam Using RKPM Meshlesh Method
, M.Sc. Thesis Sharif University of Technology ; Ahmadian, Mohammad Taghi (Supervisor)
Abstract
Due to special characteristics, nowadays functionally graded materials are of great interest of researchers. Continuous change of properties in these materials,decreases undesirable phenomena such as stresscon centration. On the other hand knowing vibration parameters of structures such as natural frequencies, to avoid damage, is important. So far, many researches have been devoted to vibration analysis of structures, such as beams.In this dissertation, free vibration analysis of FGM beams, are investigated, using RKPM, a meshlesh method. The system of equations of motion is derived using Lagrange’s method under the assumption of Euler-Bernoulli beam theory. Buckling analysis of FGM beams...
Shuffling multivariate adaptive regression splines and adaptive neuro-fuzzy inference system as tools for QSAR study of SARS inhibitors
, Article Journal of Pharmaceutical and Biomedical Analysis ; Volume 50, Issue 5 , 2009 , Pages 853-860 ; 07317085 (ISSN) ; Asadollahi Baboli, M ; Mani Varnosfaderani, A ; Sharif University of Technology
Abstract
In this work, the inhibitory activity of pyridine N-oxide derivatives against human severe acute respiratory syndrome (SARS) is predicted in terms of quantitative structure-activity relationship (QSAR) models. These models were developed with the aid of multivariate adaptive regression spline (MARS) and adaptive neuro-fuzzy inference system (ANFIS) combined with shuffling cross-validation technique. A shuffling MARS algorithm is utilized to select the most important variables in QSAR modeling and then these variables were used as inputs of ANFIS to predict SARS inhibitory activities of pyridine N-oxide derivatives. A data set of 119 drug-like compounds was coded with over hundred calculated...
Polyamide/titania hollow nanofibers prepared by core–shell electrospinning as a microextractive phase in a fabricated sandwiched format microfluidic device
, Article Journal of Chromatography A ; Volume 1528 , 2017 , Pages 1-9 ; 00219673 (ISSN) ; Hashemi Hedeshi, M ; Bagheri, H ; Sharif University of Technology
Abstract
In this study, a low–cost microfluidic device from polymethyl methacrylate was fabricated by laser engraving technique. The device is consisted of a central chip unit with an aligned microchannel. Both sides of the engraved microchannel were sandwiched by two synthesized sheets from polyamide/titania (PA/TiO2) hollow nanofibers as extractive phases. The inlet and outlet of the device were connected to the polyether ether ketone tubes, while a peristaltic pump was used to deliver both sample and desorbing solvent through the microchannel. The recorded scanning electron microscopy images from the surface of the synthesized PA/TiO2 nanofibers, exhibit a good degree of homogeneity and porosity...
A single–step synthesized supehydrophobic melamine formaldehyde foam for trace determination of volatile organic pollutants
, Article Journal of Chromatography A ; Volume 1525 , 2017 , Pages 10-16 ; 00219673 (ISSN) ; Zeinali, S ; Baktash, M. Y ; Sharif University of Technology
Abstract
Superhydrophobic materials have attracted many attentions in recent years while their application in sample preparation remained almost intact. In this project, a rough surface of melamine formaldehyde foam was silanized by chemical deposition of trichloromethylsilane to form a highly porous and superhydrophobic material, presumably a suitable medium for extracting non–polar compounds such as benzene and its methyl derivatives. The prepared sorbent was packed in a needle for the headspace needle–trap microextraction of benzene, toluene, ethylbenzene and xylenes (BTEX). Major parameters associated with the extraction/desorption processes were considered for optimization. Under the optimized...
CytoGTA: a cytoscape plugin for identifying discriminative subnetwork markers using a game theoretic approach
, Article PLoS ONE ; Volume 12, Issue 10 , 2017 ; 19326203 (ISSN) ; Foroughmand Araabi, M. H ; Goliaei, S ; Razaghi Moghadam, Z ; Sharif University of Technology
Abstract
In recent years, analyzing genome-wide expression profiles to find genetic markers has received much attention as a challenging field of research aiming at unveiling biological mechanisms behind complex disorders. The identification of reliable and reproducible markers has lately been achieved by integrating genome-scale functional relationships and transcriptome datasets, and a number of algorithms have been developed to support this strategy. In this paper, we present a promising and easily applicable tool to accomplish this goal, namely CytoGTA, which is a Cytoscape plug-in that relies on an optimistic game theoretic approach (GTA) for identifying subnetwork markers. Given transcriptomic...
Combined UV-C/H2O2-VUV processes for the treatment of an actual slaughterhouse wastewater
, Article Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes ; Volume 52, Issue 5 , 2017 , Pages 314-325 ; 03601234 (ISSN) ; Bustillo Lecompte, C. F ; Mehrvar, M ; Abdekhodaie, M. J ; Sharif University of Technology
Taylor and Francis Inc
2017
Abstract
In this study, a three-factor, three-level Box-Behnken design with response surface methodology were used to maximize the TOC removal and minimize the H2O2 residual in the effluent of the combined UV-C/H2O2-VUV system for the treatment of an actual slaughterhouse wastewater (SWW) collected from one of the meat processing plants in Ontario, Canada. The irradiation time and the initial concentrations of total organic carbon (TOCo) and hydrogen peroxide (H2O2o) were the three predictors, as independent variables, studied in the design of experiments. The multiple response approach was used to obtain desirability response surfaces at the optimum factor settings. Subsequently, the optimum...
Cuffless blood pressure estimation algorithms for continuous health-care monitoring
, Article IEEE Transactions on Biomedical Engineering ; Volume 64, Issue 4 , 2017 , Pages 859-869 ; 00189294 (ISSN) ; Kiani, M. M ; Mohammadzade, H ; Shabany, M ; Sharif University of Technology
IEEE Computer Society
2017
Abstract
Goal: Continuous blood pressure (BP) monitoring can provide invaluable information about individuals' health conditions. However, BP is conventionally measured using inconvenient cuff-based instruments, which prevents continuous BP monitoring. This paper presents an efficient algorithm, based on the pulse arrival time (PAT), for the continuous and cuffless estimation of the systolic BP, diastolic blood pressure (DBP), and mean arterial pressure (MAP) values. Methods: The proposed framework estimates the BP values through processing vital signals and extracting two types of features, which are based on either physiological parameters or whole-based representation of vital signals. Finally,...
An expert system for selecting wart treatment method
, Article Computers in Biology and Medicine ; Volume 81 , 2017 , Pages 167-175 ; 00104825 (ISSN) ; Alizadehsani, R ; Roshanzamir, M ; Khosravi, A ; Layegh, P ; Nahavandi, S ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
As benign tumors, warts are made through the mediation of Human Papillomavirus (HPV) and may grow on all parts of body, especially hands and feet. There are several treatment methods for this illness. However, none of them can heal all patients. Consequently, physicians are looking for more effective and customized treatments for each patient. They are endeavoring to discover which treatments have better impacts on a particular patient. The aim of this study is to identify the appropriate treatment for two common types of warts (plantar and common) and to predict the responses of two of the best methods (immunotherapy and cryotherapy) to the treatment. As an original work, the study was...