检索结果-南通市图书馆

Engineering（科研） 2010年第11期2卷 888-894页

作者： hala mohamed abdel mageed Ahmed Faheem Zobaa mohamed Helmy abdel Raouf Abla Hosni Abd El-Rahman mohamed Mamdouh abdel Aziz 不详

The temperature effects on the electrical performance of a large area multicrystalline silicon solar cell with back-contact technology have been studied in a desert area under ambient conditions using the current shunt measuring technique. Therefore, most of the problems encountered with traditional measuring techniques are avoided. The temperature dependency of the current shunt from 5oC up to 50oC has been investigated. Its temperature coefficient proves to be negligible which means that the temperature dependency of the solar cell is completely independent of the current shunt. The solar module installed in a tilted position at the optimum angle of the location, has been tested in two different seasons (winter and summer). The obtained solar cell short circuit current, open circuit voltage and output power are correlated with the measured incident radiation in both seasons and all results are discussed.

关键词： Large Area Multicrystalline Silicon Solar Cell Current Shunt Measuring Technique Temperature Effects Short Circuit Current Open Circuit Voltage Accumulated Power Incident Radiation

An Improved Design of a Fully Automated Multiple Output Micropotentiometer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2010年第2期2卷 103-110页

作者： hala mohamed abdel mageed Ahmed Faheem Zobaa mohamed Helmy abdel Raouf Abla Hosni Abd El-Rahman mohamed Mamdouh abdel Aziz National Institute for Standards GizaEgypt University of Exeter ExeterUK Cairo University GizaEgypt

This paper describes in details a new design of a fully automated multiple output micropotentiometer (?pot). A prototype has been built at the National Institute for Standards (NIS), Egypt to establish this highly improved AC voltage source in the millivolt range. The new device offers three different outputs covering a wide frequency range from only one outlet. This valuably supports the precise sourcing ranges of low AC voltage at NIS. The design and the operation theory of this prototype have been discussed in details. An automatic calibration technique has been introduced through specially designed software using the LabVIEW program to enhance the calibration technique and to reduce the uncertainty contributions. Relative small AC-DC differences of our prototype in the three output ranges are fairly verified. The expanded uncertainties of the calibration results for the three output ranges have been faithfully estimated. However, further work is needed to achieve the optimum performance of this new device.

关键词： Multiple Output μpot AC-DC Transfer Standard Single Junction Thermal Converter Calibration Uncertainty

Electrical Performance Study of a Large Area Multicrystalline Silicon Solar Cell Using a Current Shunt and a Micropotentiometer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Engineering（科研） 2010年第4期2卷 263-269页

作者： hala mohamed abdel mageed Ahmed Faheem Zobaa Ahmed Ghitas mohamed Helmy abdel Raouf mohamed Sabry Abla Hosni Abd El-Rahman mohamed Mamdouh abdel Aziz 不详

In this paper, a new technique using a Current Shunt and a Micropotentiometer has been used to study the electrical performance of a large area multicrystalline silicon solar cell at outdoor conditions. The electrical performance is mainly described by measuring both cell short circuit current and open circuit voltage. The measurements of this cell by using multimeters suffer from some problems because the cell has high current intensity with low output voltage. So, the solar cell short circuit current values are obtained by measuring the voltage developed across a known resistance Current Shunt. Samples of the obtained current values are accurately calibrated by using a Micropotentiometer (μpot) thermal element (TE) to validate this new measuring technique. Moreover, the solar cell open circuit voltage has been measured. Besides, the cell output power has been calculated and can be correlated with the measured incident radiation.

关键词： Large Area Multicrystalline Silicon Solar Cell Current Measurements Calibration Current Shunt Micropotentiometer Short Circuit Current Open Circuit Voltage

Molecular analysis of Pasteurella multocida strains isolated from fowl cholera infection in backyard chickens

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2014年第1期4卷 8-12页

作者： mohamed-Wael abdelazeem mohamed Moemen abdel Azeem mohamed abdel mageed Department of Microbiology Faculty of Veterinary medicineSouth Valley University Department of Poultry Diseases Faculty of Veterinary MedicineAssiut University

Objective:To characterize Pasteurella isolated from backyard chickens using whole cell protein lysate profiles and random amplified polymorphic DNA(RAPD)techniques to show their genetic relationship because Pasteurclla multocida(***)is an important cause of fatal infections in backyard ***:Twenty one *** isolates were recovered previously from clinical cases of fowl cholera belonging to individual owners and phenotypically analysed using biochemical tests and serotyping were used far the genetic ***:Phylogenetic study based on both methods revealed that the recovered population of *** isolated from backyard chickens differs markedly,constituting a well-separated cluster and appearance of 3 distinguishing lineages with greater discrimination shown by RAPDPCR that resulted in two suclusters in cluster A and three subclusters in cluster B and were related greatly with capsular serogroups for the examined *** whole cell protein revealed the presence of dominant protein bands at approximately 41 and 61 kDa in all of the examined isolates that may be a virulent proteins share in the increasing of its *** distinctive bands ranged from 123 to 1534 ***:Based on the previous findings,there are three spreading clusters that may indicate the association of a small number of *** variants with the majority of cases suggesting that certain clones of *** are able to colonue the examined backyard ***,the ease and rapidity of RAPD-PCR support the use of this technique as alternative to the more labour-intensive SDS-PACE system for strain differentiation and epidemiological studies of avian *** application of RAPD technology to the examination of avian cholera outbreaks in commercially available flocks may facilitate more effective management of this disease by providing the potential to investigate correlations of *** genotypes,to identify aff

关键词： Pasteurella multocida Chickens Variation Molecular characterization

Microhardness,microstructure and electrical properties of ZVM ceramics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2014年第4期3卷 287-296页

作者： abdel-mageed H.KHAFAGY Sanaa M.EL-RABAIE mohamed T.DAWOUD M.T.ATTIAb Physics Department Faculty of ScienceMenufiya UniversityShebin El-Koom 32511Egypt Physics and Engineering Mathematics Department Faculty of Electronic EngineeringMenufiya UniversityMenouf 32952Egypt

The effect of Mn_(3)O_(4)addition on microhardness,microstructure and electrical properties of vanadium oxide doped zinc oxide varistor ceramics is systematically *** Vicker’s microhardness HV has decreased with increasing the amount of ***,the average grain size has decreased from 27.51μm to 19.55μm with increasing the amount of Mn_(3)O_(4) up to 0.50 mol%,whereas an increase in Mn_(3)O_(4) up to 0.75 mol%has caused the average grain size to increase and then it decreases with increasing Mn_(3)O_(4)from 0.75 mol%to 1.00 mol%.The sintered density has decreased from 5.38 g/cm3 to 5.31 g/cm3 with increasing the amount of Mn_(3)O_(4).The varistor ceramic modified with 0.50 mol%Mn_(3)O_(4) has exhibited excellent nonlinear properties,with 16.29 for the nonlinear coefficient and 441.9μA/cm2 for the leakage current ***,the sample doped with 0.50 mol%Mn_(3)O_(4) has been found to possess donor density as 0.77×10^(18) cm^(-3) and 0.916 eV barrier height.

关键词： ceramics electrical properties microstructure varistor Mn3O4 doped ZnO-V2O5 varistor

Novel CYP1B1 mutations and a possible prognostic use for surgical management of congenital glaucoma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2019年第4期12卷 607-614页

作者： mohamed M.Khafagy Nadia El-Guendy Marwa A Tantawy mohamed A.Eldaly hala M.Elhilali abdel Hady A.abdel Wahab Ophthalmology Department Faculty of Medicine Cairo University Cancer Biology Department National Cancer Institute Cairo University Research Department Children's Cancer Hospital

AIM: To identify CYP1B1 gene mutations and evaluate their possible role as a prognostic factor for success rates in the surgical management of Egyptian congenital glaucoma ***: Totally 42 eyes of 29 primary congenital glaucoma patients were operated on with combined trabeculotomy/trabeculectomy with mitomycin-C and followed up at 1 d, 1 wk, 1, 6 and 12 mo postoperatively. Genomic DNA was extracted from peripheral blood leukocytes. Coding regions of CYP1B1 gene were amplified using 13 pairs of primers, screened for mutations using single-strand conformation polymorphism followed by sequencing of both strands. Efficacy of the operation was graded as either a success [maintaining intraocular pressure(IOP) less than 21 mm Hg with or without antiglaucoma medication], or a failure(IOP more than 21 mm Hg with topical antiglaucoma medications). RESULTS: Seven novel mutations out of a total of 15 different mutations were found in the CYP1B1 genes of 14 patients(48.2%). The presence of CYP1B1 gene mutations did not correlate with the failure of the surgery(P=0.156, odds ratio=3.611, 95%CI, 0.56 to 22.89); while the positive consanguinity strongly correlated with failure of the initial procedure(P=0.016, odds ratio=11.25, 95%CI, 1.57 to 80.30). However, the Kaplan-Meier survival analysis revealed a significantly lower time of IOP control in the subgroup with mutations in CYP1B1 versus the congenital primary glaucoma group without mutations(log rank test, P=0.015).CONCLUSION: Seven new CYP1B1 mutations are identified in Egyptian patients. Patients harboring confirmed mutations suffered from early failure of the initial surgery. CYP1B1 mutations could be considered as a prognostic factor for surgery in primary congenital glaucoma.

关键词： CYP1B1 mutations primary congenital glaucoma intraocular pressure trabeculotomy/trabeculectomy with mitomycin-C.

Antimicrobial activity of latex silver nanoparticles using Calotropis procera

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2014年第11期4卷 876-883页

作者： Nadia Hussein mohamed Mady Ahmed Ismail Wael Moustfa abdel-mageed Ahmed abdelfattah mohamed Shoreit Department of Botany Faculty of ScienceAssiut University Biology Department.Faculty of Science and Art SamtahJazan University Pharmacognosy Department College of PharmacyKing Saud University Pharmacognosy Department Faculty of PharmacyAssiut University

Objective:To synthesize silver nanoparticles(AgNPs) by green methods using scrum latex of Calotropis procera at 80 ℃ and evaluate them against bacteria,dermatophytes and phytopathogenic fungi comparing with the activity of untreated ***:The synthesis of AgNPs was performed by mixing 3%latex scrum extract with the same volume of silver nitrate(2 mmol/L) solution in round flask and heating in water bath at80 ℃.Characterization of silver particles were determined using UV-vis spectrophotometer,transmission electron microscopy(TEM),X-ray diffraction and Fourier transform infrared *** antimicrobial activity of the green synthesized AgNPs was determined against bacteria,dermatophytes and phytopathogenic fungi and compared to the crude untreated latex by agar-well diffusion ***:Biosynthesis of latex silver nanoparticles was successfully obtained by green *** formation of AgNPs has been confirmed by UV-vis,TEM microscopy.X-ray diffraction and Fourier transform infrared *** analysis showed that synthesized AgNPs are highly stable spherical shaped particles,well dispersed with a diameter ranged from 4 nm up to 25 nm and an average size of 12.33 *** showed strong antibacterial activity against Gram-negative bacteria(Escherichia coli,Pseudomonas aeruginosa and Serratia sp.) and antifungal activity against Trichophyton rubrum,Candida albicans and Aspergillus ***:It can be concluded that serum latex of Calotropis pmcera was found to display strong potential for the synthesis of AgNPs as antimicrobial agents through rapid reduction of silver ions(Ag^+ to Ag^0).The green synthesized AgNPs were found to show higher antimicrobial efficacy than crude latex.

关键词： Green synthesis Calotropis procera Latex Silver nanoparticles Antimicrobial activity

The effect of atomic spontaneous decay on the dynamics of the negativity of the Wigner function of radiation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2011年第9期20卷 44-48页

作者： abdel-Baset A.mohamed Faculty of Science Assiut UniversityAssiutEgypt

The exact solution of the master equation for the case of a high-Q cavity with atomic decay is found. We use the negativity of the Wigner function （WF） as an indicator of nonclassicality. It is found that the negative values of the field WF are very sensitive to any change in the damping parameter. The atomic spontaneous decay leads to the simultaneous disappearance of both entanglement and nonclassicality of quantum states. Moreover, the purity of the field states is completely lost.

关键词： non-classicality entanglement atomic decay

Analysis and Review of Downregulated Actin Cytoskeletal Proteins in Non-Small Cell Lung Cancer

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Biosciences and Medicines 2024年第4期12卷 89-115页

作者： hala M. abdel mageed Praveen Sahu Raji Sundararajan School of Engineering Technology Purdue University West Lafayette USA National Institute of Standards Al Haram Egypt

Actin, a highly conserved protein, plays a dominant role in Non-small cell lung cancer (NSCLC). Late diagnosis and the aggressive nature of NSCLC pose a significant threat. Studying the clinic pathological properties of NSCLC proteins is a potential alternative for developing treatment strategies. Towards this, 35 downregulated actin cytoskeletal proteins on NSCLC prognosis and treatment were studied by examining their protein-protein interactions, gene ontology enrichment terms, and signaling pathways. Using PubMed, various proteins in NSCLC were identified. The protein-protein interactions and functional associations of these proteins were examined using the STRING database. The focal adhesion signaling pathway was selected from all available KEGG and Wiki pathways because of its role in regulating gene expression, facilitating cell movement and reproduction, and significantly impacting NSCLC. The protein-protein interaction network of the 35 downregulated actin cytoskeleton proteins revealed that ACTG1, ACTR2, ACTR3, ANXA2, ARPC4, FLNA, TLN1, CALD1, MYL6, MYH9, MYH10, TPM1, TPM3, TPM4, PFN1, IQGAP1, MSN, and ZXY exhibited the highest number of interactions. Whereas HSPB1, CTNNA1, KRT17, KRT7, FLNB, SEPT2, and TUBA1B displayed medium interactions, while UTRN, TUBA1B, and DUSP23 had relatively fewer interactions. It was discovered that focal adhesions are critical in connecting membrane receptors with the actin cytoskeleton. In addition, protein kinases, phosphatases, and adapter proteins were identified as key signaling molecules in this process, greatly influencing cell shape, motility, and gene expression. Our analysis shows that the focal adhesion pathway plays a crucial role in NSCLC and is essential for developing effective treatment strategies and improving patient outcomes.

关键词： Non-Small Cell Lung Cancer NSCLC Actin Actin Cytoskeletal Proteins Focal Adhesion KEEG Pathway

Bitter gourd extract improves glucose homeostasis and lipid profile via enhancing insulin signaling in the liver and skeletal muscles of diabetic rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2021年第8期11卷 344-352页

作者： Saber mohamed Eweda Mennatallah Ahmed Ali hala mohamed Abd El-Bary Nahed Hussein El-Sokkary Madiha Hassan Helmy Maher abdel-Nabi Kamel Department of Biochemistry Faculty of ScienceAlexandria UniversityAlexandriaEgypt Department of Pharmacology&Therapeutics Faculty of Pharmacy and Drug ManufacturingPharos University in AlexandriaAlexandriaEgypt Department of Biochemistry Medical Research InstituteAlexandria UniversityAlexandriaEgypt Department of Physiology Faculty of MedicineAlexandria UniversityAlexandriaEgypt Medical Laboratories Technology College of Applied Medical SciencesTaibah UniversityMadinahKSA

Objective:To investigate the modulatory effects of bitter gourd extract on the insulin signaling pathway in the liver and skeletal muscle tissues of diabetic ***:The ethanolic extract of bitter gourd was prepared and its contents of total polyphenols and flavonoids were assayed.A neonatal streptozotocin-induced diabetic rat model was established and the diabetic rats were assigned into different groups and were treated with different doses of bitter gourd extract(100,200,400,or 600 mg/kg)or with glibenclamide(0.1 mg/kg)for 30 *** blood glucose,insulin,and lipid profile were evaluated and the insulin signaling pathway in the liver and skeletal muscle of rats was *** correlations between homeostasis model assessment(HOMA)and the components of insulin signaling pathway were also ***:Different doses of bitter gourd extract significantly ameliorated fasting blood glucose level and HOMA index for insulin ***,bitter gourd extract increased serum insulin and improved disrupted serum lipid *** levels of insulin receptor substrate-1(IRS-1),p-insulin receptorβ(p-IR-β),protein kinase C(PKC),GLUT2,and GLUT4 were improved by treatment with bitter gourd *** best results were obtained with 400 mg/kg dose of the extract,the effect of which was equivalent to that of *** in the bitter gourd treated rats was negatively correlated with p-IR-β,IRS-1 and PKC in hepatic and skeletal *** was also negatively correlated with skeletal muscle ***:Bitter gourd extract improves glucose homeostasis and lipid profile in diabetic rats via enhancement of insulin secretion and ***,bitter gourd can be used as a potential pharmacological agent for the treatment of type 2 diabetes mellitus.

关键词： Neonatal Streptozotocin Diabetic Sulfonylurea Bitter gourd Phosphorylated insulin receptor Protein kinase C IRS-1 GLUT2/GLUT4 Insulin signaling