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Local wavelet-based filtering of electromyographic signals to eliminate the electrocardiographic-induced artifacts in patients with spinal cord injury

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Journal of Biomedical Science and Engineering 2013年第7期6卷 1-13页

作者： Matthew Nitzken Nihit Bajaj Sevda Aslan Georgy Gimel’farb Ayman el-Baz Alexander Ovechkin BioImaging Laboratory Bioengineering Department University of Louisville Louisville USA Department of Computer Science The University of Auckland Auckland New Zealand Department of Neurological Surgery University of Louisville Louisville USA Frazier Rehab Institute Louisville USA Department of Neurological Surgery University of Louisville Louisville USA Frazier Rehab Institute Louisville USA

Surface electromyography (EMG) is a standard method used in clinical practice and research to assess motor function in order to help with the diagnosis of neuromuscular pathology in human and animal models. EMG recorded from trunk muscles involved in the activity of breathing can be used as a direct measure of respiratory motor function in patients with spinal cord injury (SCI) or other disorders associated with motor control deficits. However, EMG potentials recorded from these muscles are often contaminated with heart-induced electrocardiographic (ECG) signals. elimination of these artifacts plays a critical role in the precise measure of the respiratory muscle electrical activity. This study was undertaken to find an optimal approach to eliminate the ECG artifacts from EMG recordings. Conventional global filtering can be used to decrease the ECG-induced artifact. However, this method can alter the EMG signal and changes physiologically relevant information. We hypothesize that, unlike global filtering, localized removal of ECG artifacts will not change the original EMG signals. We develop an approach to remove the ECG artifacts without altering the amplitude and frequency components of the EMG signal by using an externally recorded ECG signal as a mask to locate areas of the ECG spikes within EMG data. These segments containing ECG spikes were decomposed into 128 sub-wavelets by a custom-scaled Morlet Wavelet Transform. The ECG-related subwavelets at the ECG spike location were removed and a de-noised EMG signal was reconstructed. Validity of the proposed method was proven using mathematical simulated synthetic signals and EMG obtained from SCI patients. We compare the Rootmean Square Error and the Relative Change in Variance between this method, global, notch and adaptive filters. The results show that the localized wavelet-based filtering has the benefit of not introducing error in the native EMG signal and accurately removing ECG artifacts from EMG signals.

关键词： EMG De-Noising ECG Local Wavelet Filtering

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A Finite element Model for Recognizing Breast Cancer

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Journal of Biomedical Science and Engineering 2014年第5期7卷 296-306页

作者： Ashraf Ali Wahba Nagat Mansour Mohammed Khalifa Ahmed Farag Seddik Mohammed Ibrahim el-Adawy Faculty of Engineering Biomedical Engineering Department Helwan University Cairo Egypt Radio-Diagnosis National Cancer Institute Cairo University Cairo Egypt

Breast cancer recognition is an important issue in elastography diagnostic imaging. Breast tumor biopsy has been for many years the reference procedure to assess histological definition for breast diseases. But biopsy measurement is an invasive method besides it takes larger time. So, fast and improved methods are needed. Using elastography technology, a digital image correlation technique can be used to calculate the displacement of breast tissue after it has suffered a compression force. This displacement is related to tissue stiffness, and breast cancer can be classified into benign or malignant according to that displacement. The value of compression force affects the displacement of tissue, and then affects the results of the breast cancer recognition. Finite element method was being used to simulate a model for the breast cancer as a phantom to be used in measurements and study of breast cancer diagnosis. The breast cancer using this phantom can be recognized within a short time. The proposed work succeeded in recognizing breast tumor phantom by an average correct recognition ratio CRR of about 94.25% on a simulation environment. The strain ratio SR for benign and malignant models is also computed. The result of the simulated breast tumor model is compared with real data of 10 lesion cases (6 benign and 4 malignant). The coefficient of variation CV between the simulated SR and the SR using real data reaches to about 5% for benign lesions and 4.78% for malignant lesions. The results of CRR and CV in this proposed work assure that the proposed breast cancer model using finite element modeling is a robust technique for breast tumor simulation where the behavior of real data of breast cancer can be predicted.

关键词： Breast Cancer Digital Image Correlation Ultrasound elastography Strain Analysis Breast Cancer Diagnosis

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The Inhibitive Effect of 3-Methyl 4-Amino 1,2,4 Triazole on the Corrosion of Copper-Nickel 70 - 30 in NaCl 3% Solution

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Materials Sciences and Applications 2011年第9期2卷 1260-1267页

作者： Tayeb Chieb Kamel Belmokre Mohammed Benmessaoud Sidi el Hassane Drissi Najat Hajjaji Abdellah Srhiri 不详

The effect of 3-methyl 4-amino 1,2,4 triazole (MATA) on the corrosion behaviour of copper-nickel 70 - 30 (Monel) in NaCl 3% solution is investigated at 298 K by weight loss measurements, potentiodynamic polarisation and impedance spectroscopy (EIS′) methods. Preliminary screening of the inhibition efficiency (ECR) was carried out with using weight- loss measurements. Polarization measurements showed that the organic compound investigated is mixed type inhibitor (it acts on the cathodic and the cathodic reactions), inhibiting the corrosion of Monel by blocking the active sites of the metal surface. Changes in the impedance parameters charge transfer resistance (Rct) and double layer capacitance (Cdl) are related to adsorption of organic inhibitor of the metal surface, leading to the formation of protective film, which grows with increasing exposure time. Inhibition efficiencies obtained from cathodic Tafel plots, gravimetric and EIS methods are in good agreement. Results obtained shows that the (MATA) is good inhibitor for copper – nickel, and its efficiency reaches more than 95% at 60 ppm after 30 mn of immersion.

关键词： Copper-Nickel Triazole Inhibitor Efficiency Polarisation Impedance

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Relation between the Actual and Estimated Maximum Ground Level Concentration of Air Pollutant and Its Downwind Locations

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Open Journal of Air Pollution 2020年第2期9卷 27-35页

作者： Khaled S. M. Essa Soad M. Etman Maha S. el-Otaify Mathematics and Theoretical Physics Department NRC/AEA Cairo Egypt

In this work we used the Gaussian plume model to calculate the actual maximum ground level concentration (MGLC) of air pollutant and its downwind location by using different systems of dispersion parameters and for different stack heights. An approximate formula for the prediction of downwind position that produces the MGLC of a pollutant based on the Gaussian formula was derived for different diffusion parameters. The derived formula was used to calculate the approximate MGLC. The actual and estimated values are presented in tables. The comparison between the actual and estimated values was investigated through the calculation of the relative errors. The values of the relative errors between the actual and estimated MGLC lie in the range from: 0 to 70.2 and 0 to 1.6 for Pasquill Gifford system and Klug system respectively. The errors between the actual and estimated location of the MGLC lies in the range from: 0.2 to 227 and 0.7 to 9.4 for Pasquill Gifford system and Klug system respectively.

关键词： Gaussian Plume Model Actual and Estimated Values Relative Errors

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The Ciliate Protist <i>Tetrahymena pyriformis</i>as a Cellular Adhesion Model for the Pathogenic Bacterium <i>Staphylococcus aureus</i>

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Advances in Bioscience and Biotechnology 2017年第12期8卷 491-507页

作者： Bouchra el Khalfi Mohammed Benlahfid Sofia Jarmouni Nezha Senhaji Aurelio Serrano Delgado Abdelaziz Soukri Laboratory of Physiopathology Genetics Molecular and Biotechnology (PGMB) Faculty of Sciences Ain Chock Research Center: Health & Biotechnology University Hassan II of Casablanca Casablanca Morocco Laboratory of Genetic and Molecular Pathology (LGPM) Medical School Hassan II University Casablanca Morocco Institute of Biochemistry Vegetal and Photosynthesis (IBVF-CSIC University of Seville) Seville Spain

Staphylococcus aureus is one of the main pathogenic agents responsible for nosocomial and community-acquired bacterial infections. The pathogenicity of this Gram-positive bacterium is ensured by its different adhesion factors. Collagen and the extracellular glycoprotein adhesin are among the Staphylococcus most important virulence factors. It has been shown that most of the S. aureus strains carry the ica operon, responsible for biofilm production. However, the coexpression of the icaA and the icaD genes is necessary for complete biofilm synthesis. The aim of our study was to study a collection of 15 clinical strains of S. aureus from different sources for the presence of can and icaD genes coding intercellular adhesion proteins. We also intended to estimate the strains’ ability to form biofilms by the red Cong method and to test the adhesion ability of S. aureus to the ciliated protist Tetrahymena pyriformis, which we used as a novel cellular adhesion model. Finally, we checked the adhesion’s inhibition capacity of some plants extracts. The molecular detection of adhesion genes revealed that 80% of strains are cna positive, and 73% are icaD positive. Qualitative biofilm production of S. aureus revealed that 66.6% of strains were slime producers. The adhesion test revealed that 20% of strains are strongly adhering to T. pyriformis and that the Clematis cirrhosa extract has an anti-adhering effect of S. aureus to the ciliate T. pyriformis.

关键词： Staphylococcus aureus Adhering Genes (can and icaD) Tetrahymena pyriformis Biofilm Production Plant Extract Anti-Adhesion Effect

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Synthesis and Characterization of Porous Carbon from Petroleum Pitch Using KOH

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Journal of Materials Science and Chemical Engineering 2018年第7期6卷 53-69页

作者： C. Srinivasakannan Mohammad el-Mootassem K. Suresh Kumar Reddy Ahmed Al Shoaibi Chemical Engineering Department Khalifa University of Science and Technology The Petroleum Institute Abu Dhabi UAE

Preparation and process optimization of porous carbons using different carbon sources and activating agents are frequently and commonly reported in open literature. However, only scanty references are made on utilization of petroleum coke for conversion to high surface area porous carbon using KOH as the activating agent. Hence, the present work attempts a process optimization exercise to prepare high surface area porous carbon from Petroleum coke using chemical activation (KOH) utilizing design of experiments. The effect of activation temperature, petroleum coke to KOH ratio (KPR) and activation duration were assessed on the surface area and yield of the porous carbon. The process optimization was performed covering experimental parameters in the range of 500?C - 800?C, 2 - 5 and 30 - 120 min. The optimal process conditions for maximizing the yield and BET surface area was identified to be an activation temperature of 639?C, KPR of 4.5 and activation duration of 43 min, having BET surface area 1765 m2/g and yield of 89.8%. However, an attempt to maximize only the BET surface area, ignoring yield has resulted with a porous carbon with maximum surface area of 2061 m2/g, with the optimal process conditions being an activation temperature of 688?C, KPR of 3.8 and activation duration of 74 min, with the corresponding yield of only 77%. The characterization of porous carbon was performed using nitrogen adsorption isotherm, FT-IR and SEM analysis.

关键词： Petroleum Coke Porous Carbon KOH Activation ANOVA Optimization

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Measurement of Radon Exhalation Rate in Some Building Materials Using Nuclear Track Detectors

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World Journal of Nuclear Science and Technology 2015年第3期5卷 141-148页

作者： Hesham A. Yousef A. H. el-Farrash A. Abu ela Q. Merza Physics Department Faculty of Science Suez University Suez Egypt Physics Department Faculty of Science Mansoura University Mansoura Egypt

In this paper, forty samples of building materials collected from local market in Dakahlia Governorate, Egypt. The radon concentration in these samples were measured using solid state nuclear track detector. Solid state nuclear track detectors have become an important tool in every investigation of the radon levels in the surrounding environment. The obtained results have shown that the highest average of radon concentration in granite samples and the average value is 845.43 Bqm-3, while the lowest average value is white cement 68.42 Bqm-3. The present work is important to detect any harmful radiation in our houses that affect human and to establish a data base for building materials which, used in a local market. The obtained results show that the radon concentrations of the most samples are below the allowed limit of ICRP.

关键词： Radon Radioactivity Building Materials Radiation LR-115

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Atypical Renal Cysts: Is MRI a Compulsory Examination in 2020 before Therapeutic Management?

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Open Journal of Urology 2020年第10期10卷 253-262页

作者： Idriss Ziani Ahmed Ibrahimi Hamza Dergamoun Omar Belouki Hachem el Sayegh Lounis Benslimane Yassine Nouini Urological Surgery Department “A” IBN Sina University Hospital CHU RABAT Rabat Morocco RABAT Faculty of Medicine Mohammed V University Rabat Morocco

Introduction: Kidney cancer represents 2% to 3% of malignant tumors, with an incidence of 5.8/100,000 in Western countries, a very specific subgroup of renal tumors that are cystic tumors. In fact, almost 50% of the population over 50 has a renal cyst. Materials and Methods: The objective of this study is to establish a correlation between the preoperative Bosniak score and the postoperative anatomopathological analysis in order to answer this question, the use of contrast ultrasound or MRI should be systematically performed before an atypical renal cyst? This is a retrospective study of 50 patients treated for renal cysts between January 2010 and March 2016. All patients have an abdominopelvic ultrasound and an abdominal scanner. Cysts have been classified according to the Bosniak classification. We treated our patients based on the radiological examination urocsanner and we classified our patients according to the classification of Bosniak, and uro MRI was performed in cases of atypical cysts or diagnostic doubt before considering a therapeutic attituderding to the classification of Bosniak. Results: In our work, the Uro MRI was sharper for atypical cysts (type IIF and Type III cyst) with sensitivity greater than that of the scanner but with a specificity similar to that of the scanner. And therefore be a key examination in the atypical kidney cysts. Conclusions: URO MRI is currently in 2020 a key examination of atypical bonsiak IIf and III cysts before management of the therapeutic load.

关键词： Atypical Cyst BosniaK Cystic Tumors URO MRI

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Response of Jatropha on a Clay Soil to Different Concentrations of Micronutrients

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American Journal of Plant Sciences 2012年第10期3卷 1376-1381页

作者： A. A. Abd el-Kader M. M. Hussein A. K. Alva Soils and Water Use Department National Research Center Cairo Egypt United States Department of Agriculture—Agricultural Research Service Vegetable and Forage Research Prosser USA Water Relations and Field Irrigation Department National Research Center Cairo Egypt

In recent years Jatropha curcas L. has emerged as a biofuel crop with potential for its production in marginal land with application of treated sewage water. Since this is a new crop for its profitable cultivation, additional research is needed to develop optimal management programs, including macro and micronutrients applications. A pot experiment was conducted in a Greenhouse at the National Research Center, Dokki, Cairo, Egypt, during 2010 summer to evaluate effects of varying concentrations of iron (Fe), manganese (Mn), and zinc (Zn) in irrigation water (0, 50, 100, 150, 200 and 250 ppm) on the growth, biomass production, photosynthetic pigments, and mineral nutrients status in the plants. Increasing concentrations of Fe, Mn, and Zn in irrigation water up to 150 ppm increased the biomass weight, photosynthetic pigments, and nutrient uptake by Jatropha plants. Further increase in concentrations of micronutrients showed negative effects on the above response parameters. Therefore, this study demonstrates that Jatropha can be grown under irrigation using waste water containing reasonable concentrations of micronutrients and heavy metals. This property of Jatropha provides some support for potential use of this crop for phytoremediation of metal contaminated soils. However, long term field research is needed to further verify both the above beneficial effects.

关键词： Irrigation Growth Jatropha curcas L. Mineral nutrition Photosynthetic Pigments Heavy Metals Sewage Sludge

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Groundwater Chemical Evolution in the Essaouira Aquifer Basin—NW Morocco

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Open Journal of Modern Hydrology 2013年第3期3卷 130-137页

作者： Mohammed Bahir Rachid el Moukhayar Najiba Chkir Hamid Chamchati Paula Galego Fernandes Paula Carreira Geodynamics Laboratory Magmatic Géoressources and Georisks Université Cadi Ayyad Marrakech Morocco Geography Departement Faculty of Letters and Humanities Sfax University Sfax Tunisia Nuclear Technology Institute Sacavém Portugal.

The sustainability of groundwater resources for drinking water supplies, agriculture, and industry a prime concern in countries dominated by arid and semi-arid climates such as Morocco. The growing demand for groundwater coupled with impacts from land use and climate change make sustainability an even more important water management goal. In order to make sound decisions about water use and protection of water quality, managers and policy makers must have a sound understanding of such factors as the location and amount of groundwater recharge and groundwater ages. Due to the population growth and climate change (causing long periods of drought) in the world, many countries have intensively increased their use of water sources for supplying potable water to population and for their agricultural (irrigation) and industrial developments. Due to the lack of surface waters, people exploit mainly underground water reservoirs. So, it is necessary to study and characterize these water reservoirs to avoid any excess of exploitation. The water resources of the Essaouira basin are characteristic of a semi-arid climate, and are severely impacted by the climate (quantity and quality). Considering the importance of the Essaouira aquifer in the groundwater supply of the region, a study was conducted in order to comprehend this aquifer groundwater evolution. It is an aquifer located on the Atlantic coastline, southern (Morocco), corresponding to a sedimentary basin with an area of near200 km2. Covering the Palaeozoic bedrock, the sedimentary series range from the Triassic to the Quaternary. The geological structures delineate a syncline bordered by the Tidzi diapir of Triassic age which outcrops to the East and South. In the Essaouira basin a multi-aquifer was identified constituted by detrital deposits of the Plioquaternary and dolomitic limestones of the Turonian. The Plioquaternary is unconfined below the Senonian marls. However, in some places it can be in direct contact with t

关键词： Essaouira Basin Aquifer Hydrogeochemistry Mass Balance Model

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