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Semiautomatic detection of lanes and bands in DNA gel electrophoresis images

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Journal of Biomedical Science and Engineering 2013年第1期6卷 76-84页

作者： ashraf k. helmy Ghada S. El-Tawel Computer Science Department Faculty of Computers and Informatics Suez Canal University Ismailia Egypt National Authority of Remote Sensing and Space Sciences El Nozha El-Gidida Cairo Egypt

The following article has been retracted due to the investigation of complaints received against it. The Editorial Board found that the same contents have been published in another journal at the same time. The scientific community takes a very strong view on this matter, and the Journal of Biomedical Science and Engineering treats all unethical behavior such as plagiarism seriously. This paper published in Vol.6 No.1 76-84, 2013 has been removed from this site. Title: Semiautomatic detection of lanes and bands in DNA gel electrophoresis images Authors: ashraf k. helmy, Ghada S.

关键词： Gel Electrophoresis (GE) Lane Comparison Matched Filter Lane Segmentation Lane Detection

Promotive action of 2-acetylaminofluorene on hepatic precancerous lesions initiated by diethylnitrosamine in rats:Molecular study

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World Journal of Hepatology 2021年第3期13卷 328-342页

作者： Amany helmy Hasanin Eman k Habib Nesreen El Gayar Marwa Matboli Clinical Pharmacology Department Faculty of MedicineAin Shams UniversityCairo 11318Egypt Anatomy and Embryology Department Faculty of MedicineAin Shams UniversityCairo 11318Egypt Medical Biochemistry and Molecular Biology Department Faculty of MedicineAin Shams UniversityCairo 11381Egypt

BACkGROUND Diethylnitrosamine(DEN)induces hepatic neoplastic lesions over a prolonged *** To investigate the promotive action of 2-acetylaminofluorene(2-AAF)when combined with DEN in order to develop a rat model for induction of precancerous lesion and investigate the molecular mechanism underlying the activity of *** The pre-precancerous lesions were initiated by intraperitoneal injection of DEN for three weeks consecutively,followed by one intraperitoneal injection of 2-AAF at three different doses(100,200 and 300 mg/kg).Rats were separated into naïve,DEN,DEN+100 mg 2-AAF,DEN+200 mg 2-AAF,and DEN+300 mg 2-AAF *** were sacrificed after 10 wk and 16 *** functions,level of alpha-fetoprotein,glutathione S-transferase-P and proliferating cell nuclear antigen staining of liver tissues were *** mRNA level of RAB11A,BAX,p53,and Cyclin E and epigenetic regulation by long-noncoding RNA(lncRNA)RP11-513I15.6,miR-1262(microRNA),and miR-1298 were assessed in the sera and liver tissues of the *** 2-AAF administration significantly increased the percent area of the precancerous foci and cell proliferation along with a significant decrease in RAB11A,BAX,and p53 mRNA,and the increase in Cyclin E mRNA was associated with a marked decrease in lncRNA RP11-513I15.6 expression with a significant increase in both miR-1262 and *** 2-AFF promoted hepatic precancerous lesions initiated through DEN by decreasing autophagy,apoptosis,and tumor suppression genes,along with increased cell proliferation,in a time-and dose-dependent *** actions were mediated under the epigenetic regulation of lncRNA RP11-513I15.6/miR-1262/miR-1298.

关键词： Acetylaminofluorene Hepatic precancerous lesion Diethylnitrosamine Autophagy Apoptosis MicroRNA

Rock composition and origin of the Duwi Formation calcareous rocks, Upper Egypt

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Chinese Journal Of Geochemistry 2005年第4期24卷 316-326页

作者： Baioumy H.M. Attia A.M. Boulis S.N. Hassan M.S. helmy M.E. Central Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptGeology Dept. Faculty of Science Ain Shams University Abbasia Cairo Egypt

Upper Cretaceous phosphorite beds of the Duwi Formation, Upper Egypt, are intercalated with limestone, sandy limestone, marl, calcareous shales, and calcareous sandstone. Calcareous intercalations were subjected to field and detailed petrographic, mineralogical and geochemical investigations in order to constrain their rock composition and origin.; Mineralogically, dolomite, calcite, quartz, francolite and feldspars are the non-clay minerals. Smectite, kaolinite and illite represent the clay minerals. Major and trace elements can be classified as the detrital and carbonate fractions based on their sources. The detrital fraction includes the elements that are derived from detrital sources, mainly clay minerals and quartz, such as Si, Al, Fe, Ti, k, Ba, V, Ni, Co, Cr, Zn, Cu, Zr, and Mo. The carbonate fraction includes the elements that are derived from carbonates, maily calcite and dolomite, such as Ca, Mg and Sr. ; Dolomite occurs as being dense, uniform, mosaic, very fine-to-fine, non-ferroan, and non-stoichiometrical, suggesting its early diagenetic formation in a near-shore oxidizing shallow marine environment. The close association and positive correlation between dolomite and smectite indicates the role of clay minerals in the formation of dolomite as a source of Mg{2}-rich solutions.; Calcareous rocks were deposited in marine, oxidizing and weakly alkaline conditions, marking a semi-arid climatic period. The calcareous/argillaceous alternations are due to oscillations in clay/carbonate ratio.

关键词：岩石埃及石灰质白云石成岩作用

Automated dual source systems for measurement of DC resistance standards

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Journal of Measurement Science and Instrumentation 2019年第2期10卷 109-115页

作者： Rasha S M Ali M helmy A Raouf Dept.of Electrical Quantities Metrology National Institute for Standards(NIS)Giza 12211-136Egypt

A new system for measuring low-ohmic standard resistors through a dual current sources bridge is *** is used for low resistance measurements from 1 mΩto 1Ωat 1∶1 ratio,which is suitable for the laboratories without cryogenic current comparators(CCC)or direct current comparators(DCC)*** of this bridge is evaluated by comparing its measured values with the unknown resistor values obtained by another *** accuracy of the introduced bridge is in the level of 10-5 for the 1 mΩresistor,and in the level of 10-4 for the 10 mΩ,100 mΩand 1Ω***,a dual voltage sources system for the measurement of DC standard resistors from 1 kΩto 100 MΩis also *** this system,a modification is made on the modified Wheatstone bridge to evaluate its performance by adding another digital multimeter to measure the ratio between the unknown and the standard resistors *** bridge is verified by comparing the measured values of 10 kΩresistor obtained by the two methods with its actual *** bridge accuracy is in the level of 10-6 except for the 1 kΩresistor,and the bridge asymmetry is also *** is found the asymmetry is in the level of 10-6 for the resistors from 10 kΩto 100 MΩand in the level of 10-5 for 1 kΩ*** introduced bridges operations are controlled by LabVIEW programs designed specially for this purpose,and the expanded uncertainty is also evaluated for all measurement results.

关键词： direct current comparators voltage null detector modified Wheatstone bridge ratio technique resistance measurements uncertainty

Photo Acoustic Thermal for Human Bone Characterization: A Feasibility Study

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Journal of Biomedical Science and Engineering 2016年第9期9卷 445-449页

作者： James Rizkalla Vinay kumar Suryadevara Ashok kumar Thella Ahdy helmy Paul Salama Maher E. Rizkalla Indiana University School of Medicine Indianapolis IN USA Electrical and Computer Engineering Indiana University Purdue University Indianapolis (IUPUI) Indianapolis IN USA Integrated Nanosystems Development Institute (INDI) Indiana University Purdue University Indianapolis (IUPUI) Indianapolis IN USA

The possible features of photo acoustic tomography (PAT) in medical research and practice, including applications in orthopedics and cardiovascular areas, among others, have motivated the emphasis of this study towards human bone applications. PAT modality is an emerging approach that features safety and greater penetration depth compared to other modalities such as X-ray and microwave. The high-resolution images and safety related to PAT modality are attributed to the scattering properties of ultrasound as compared to light within a human tissue. PAT brought considerable attention from the medical research community to target optimum parameters for practical models. It includes source frequency penetration depth, dynamic temperature responses, and acoustic pressure throughout the multilayer structure of the human tissues. In this work, the acoustic pressure and the bio-heat equations were analyzed for power distribution and penetration depth, covering the basic principles of PAT within the human body. Three sources with three dif-ferent heat energy pulses;1 s, 3 s, and 5 s, were considered in order to study the rise time and fall time dynamic responses inside the bone material. The computer simulation was designed to simu-late the human tissue at 1 MHz with an acoustic pressure of 1 MPa. A penetration depth for all sources was estimated to be near 4 cm with a temperature change from 0.5 k to near 1 k over a pe-riod of 10 s. The simulation data provide promising results when taken to the next level of practical implementation. The 4 cm penetration depth range may enable the researchers to investigate mul-tiple layers within the human body, leading to non-invasive deterministic approach. The simulation presented here will serve as a pilot study towards photoacoustic applications in orthopedic applica-tions.

关键词： Photoacoustic Tomography PAT PA Ortho COMSOL

Photo Acoustic Energy Applications for the Detection of Human Arterial Blockages via Multiple Skin/Bone Layers, a Non-Invasive Approach

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World Journal of Cardiovascular Diseases 2017年第8期7卷 251-270页

作者： Monika kakani Neeraj Rathi Ahdy helmy Ashok kumar Thella M. D. James Rizkalla Paul Salama Maher E. Rizkalla Department of Electrical and Computer Engineering Indiana University Purdue University Indianapolis (IUPUI) Indianapolis USA VA Hospital Indiana University School of Medicine Indianapolis USA Baylor University Medical Center (BUMC) Dallas USA Integrated Nanosystems Development Institute IUPUI Indianapolis USA Richard G. Lugar Center for Renewable Energy IUPUI Indianapolis USA

The impact of arterial narrowing/blocking caused by plaque buildup in arteries leads to many life-threatening consequences. This is recognized as a cause in heart attacks and peripheral vascular disease. Diagnosing the illness is only feasible after symptoms have presented to the patient. Currently, the standard for visualizing coronary arteries is through angiography, which may have complications, and impact on the healthcare system. Furthermore, cardiac catheterization may also places high health risks, given its overall invasiveness. Cardiac arrhythmias, infection, and contrast dye nephrotoxicity are recognized complications within this process. Therefore, a noninvasive approach may have potentials to reduce patient complications, finances surrounding healthcare, and more efficient patient care through earlier screening and diagnosing. This research addresses a new approach using photoacoustic (PA) imaging. The transmission properties of atherosclerosis within walls of arteries, can be exploited using photo acoustics, to better visualize and characterize the degree and severity of atherosclerosis. The delivered energy is absorbed by components of the vascular tissue converted into heat, leading to transient thermos elastic expansion, which creates an acoustic emission. The thermal response was analyzed for its fall and recovery times that are attributed to the artery fat type. The control parameters, including the frequency, penetration depth, energy levels, and tissue layer sizes, for multilayered structures were considered. The structures investigated were fatty infiltrate within the artery, blood, bones, and skin, within frequency range from 1 MHz to 3 MHz, and typical tissue sizes in the milli to centimeter range. As high as 14 MPas in the acoustic pressure at 1 MHz, resulted in temperature difference of up to 3.4 k. When the operating frequency was altered to 2 MHz, the temperature changed to 23 k. Furthermore, when the frequency was changed to 3 MHz, the te

关键词： Acoustic Thermal Cardiovascular Diagnosis MEMS/NEMS COMSOL Multilayers Non-Invasive

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蒙脱石颗粒的化学电泳

国外火山地质 1988年第1期 98-103页

作者： A.k.helmy I.M.Natale M.E.Mandolesi R.M.Santamaria 蔡华生

本文研究了在铝、铁、锌和铜等金属受到HF和H2O2腐蚀溶解的系统中,Na、k、Li和Ca型蒙脱石的化学电泳现象。从中发现粘土的淀积和金属的溶解量与时间的平方根成函数关系。表明系统中的电化学反应速度主要决定于反应物向金属一液体接触界... 详细信息

本文研究了在铝、铁、锌和铜等金属受到HF和H2O2腐蚀溶解的系统中,Na、k、Li和Ca型蒙脱石的化学电泳现象。从中发现粘土的淀积和金属的溶解量与时间的平方根成函数关系。表明系统中的电化学反应速度主要决定于反应物向金属一液体接触界面的扩散速率。淀积量随着粘土浓度的增加而增加。Ca型粘土的淀积量比Na、k和Li型粘土低。已经证明,为了计算颗粒的淌度（颗粒在单位电场梯度中的迁移速度——译者注）,单靠化学电泳实验所提供的数据还不够。

关键词：粘土颗粒饱和甘汞电极悬浮体系金属板板材