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Open Journal of ecology 2014年第14期4卷 907-917页

作者： Sherifa Shaker Hamed eman Hashem Radwan Gaber Ahmed saad Department of Zoology College of Science King Saud University Saudi Arabia KSA Department of Zoology Faculty of Science Alexandria University Alexandria Egypt Department of Zoology Faculty of Science Damnhour University El Behara Egypt Department of Biology College of Medicine Dammam University Saudi Arabia KSA

There has been an increasing interest in marine oysters (order: Petridae) in recent years because their numbers are declining in many parts of the world and also because they are used as monitors of pollution. The present study describes the microscopic structure of gills as viewed by light and electron microscopy in two locations selected in Alexandria coast, eastern Harbor (e.H.) and el Asafra. The specimens in the e.H. represent the presence of extracellular mineralized granules.

关键词： Gill Bivalve Transmission electron Microscope Pinctada radiata

Organic-inorganic hybrid Sn-based perovskite photodetectors with high external quantum efficiencies and wide spectral responses from 300 to 1000 nm

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Science China Materials 2019年第6期62卷 790-796页

作者： Yukun Wang Dezhi Yang Dongge Ma Dong Ha Kim Tansir Ahamad saad M. Alshehri Agafbnv Vadim Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology Department of Chemistry and Nano Science Ewha Womans University Department of Chemistry College of ScienceKing Saud University Moscow Institute of Physics and Technology Dolgoprudny

Organic-inorganic hybrid perovskites are ideal materials for photodetection owing to their high charge carrier mobility, long charge carrier diffusion length, low dark current density and sharp absorption edge. However, a relatively small band gap(1.6 e V) limits their photonharvesting efficiency in the near-infrared region. In the present work, we demonstrate a hybrid methylamine iodide and Pb-Sn binary perovskite as the light absorption layer in photodetectors. experimentally, the wavelength of photoresponse onset for the photodetectors can be extended to as great as 1,000 nm when the Sn content of the hybrid perovskite is increased to 30 mol%. In addition, the photodetectors exhibit a photoresponsivity of 0.39 A W^-1, a specific detectivity of 7×10^12 Jones, a fast photoresponse with rise and decay time constants and an external quantum efficiency greater than 50% in the wavelength range of350–900 nm, with a maximum value of about 80% at 550 nm.

关键词： organic-inorganic hybrid perovskite photodetector external quantum efficiency spectral response specific detectivity

Phenolic composition and antioxidant properties of eryngium maritimum (sea holly)

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Journal of Coastal Life Medicine 2017年第5期5卷 212-215页

作者： Ilhem Rjeibi Anouar Ben saad Sana Ncib Sami Souid Research Unit of Macromolecular Biochemistry and Genetic Faculty of Sciences of GafsaGafsa2112Tunisia Common Services Unit for Research Faculty of Sciences of GafsaGafsa2112Tunisia

Objective: To examine the antioxidant potential of Tunisian eryngium maritimum (e. maritimum) leaf, root and stems extracts, as well as their phenolic compositions. Methods: The antioxidant activity of different extracts was assessed using DPPH free radical and hydrogen peroxide scavenging assays. Phenolic profiles were determined by means of liquid chromatography (HPLC-DAD). Results: All plant parts were a rich source of phenolics. Polyphenols and flavonoids were present in leaf extracts. e. maritimum leaf extracts displayed the strongest H2O2 scavenging activity (IC50 = 76.83 μg/mL) and the highest DPPH scavenging activity value (IC50 = 47.87 μg/mL) compared to other extracts. Good relationships were observed between antioxidant activities and the total phenolic and flavonoid contents. Nine bioactive compounds were detected in e. maritimum extracts. Conclusions: Our results provided evidence that e. maritimum could be an interesting source of natural antioxidant that can be used to treat divers diseases.

关键词： eryngium maritimum Phenolic compositions Antioxidant activity

A Novel Method for PID Tuning Using a Modified Biogeography-Based Optimization Algorithm

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A Novel Method for PID Tuning Using a Modified Biogeography-...

Synthesis, Characterization and Antimicrobial Activity of Schiff Base (e)-N-(4-(2-Hydroxybenzylideneamino) Phenylsulfonyl) Acetamide Metal Complexes

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作者： M. M. Sayed M. S. saad H. M. emara e. e. Abou el-Zahab the department of electrical Power and Machines Cairo UniversityEgypt.

Proportional integral derivative （PID） controller tuning is an area of interest for researchers. This paper presents a novel method for PID controller tuning using a modified biogeography-based optimization（MBBO） algorithm. Biogeography-based optimization （BBO） is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. In this paper, a modified version of the BBO is proposed to improve its convergence. The MBBO algorithm is compared with the BBO using benchmarks functions. The proposed algorithm is applied to the problem of PID controller tuning and is compared with conventional biogeography-based optimization （BBO）, and Particle swarm optimization （PSO）.

关键词： Process Control evolutionary algorithm (eA) Biogeography-Based Optimizationand PID controller

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American Journal of Analytical Chemistry 2016年第3期7卷 233-245页

作者： Ahmad Sabry Abu-Khadra Rabie.saad Farag Alaa el-Dine Mokhtar Abdel-Hady Department of Basic Science Faculty of Engineering Science Sinai University Arish Egypt Department of Chemistry Faculty of Science Al-Azhar University Cairo Egypt Department of Pharmaceutical Chemistry Faculty of Pharmacy Sinai University Arish Egypt

New series of Ag, Cd(II), Ce(III), Co(II), Cr(III), Fe(III), Ni(II) and Pb(II) complexes with (e)-N-(4-(2- hydroxybenzylideneamino) phenylsulfonyl) {S.S} have been synthesized. These compounds have been characterized by different physico-chemical techniques like, melting point, elemental analysis, FT-IR, UV spectroscopy, 1H NMR spectroscopy, conductance measurements, magnetic susceptibility and mass spectral analysis. The metal ions concentrations have been determined using inductively coupled plasma mass spectrometry (ICP-MS). Spectroscopic studies suggest coordination most of complexes in a regular octahedral arrangement in 2L:1M molar ratio by two N azomethine and two OH phenolic from Schiff base {S.S} in the form of [ML2(H2O)2], M metal, L ligand {S.S}. Complexes have been screened for their antibacterial {Gram negative bacteria (escherichia coli and Pseudomonas aeruginosa)}, {Gram positive bacteria (Bacillus subtilis and Sterptococcus pneumoniae)} and antifungal (Aspergillus fumigates and Candida albicans) showing promising antimicrobial biological activity.

关键词： Biological Activity Inductively Coupled Plasma Synthesis Sulfacetamide Transition Metal Complexes

The Impact of Implementing the International Convention on the Control of Harmful Anti-fouling Systems in Ships （AFS Convention） on the Marine environment

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Journal of Shipping and Ocean engineering 2016年第1期6卷 57-63页

作者： Capt. Ahmed saad Hassan Noufal Capt. Mohamed Hussein Nassar Hassan Arab Academy for Science Technology & Maritime Transport Alexandria 21913 Egypt

Marine fouling is the settlement and growth of a variety of marine organisms, such as bacteria, diatoms, protozoa and algae spores on structures immersed in seawater, such as ship＇s hulls, navigation buoys, and sonar equipment. Anti-fouling refers to material or systems used to prevent the accumulation of biological material on submerged surfaces. Bio-fouling results in higher fuel consumption and can also facilitate the transport of harmful NIS （Non-Indigenous Species）. Antifouling technologies incorporating biocides （e.g., Tributyltin） have been developed to prevent fouling. Their widespread use, however, raised concerns about their toxic effects on marine communities. The AFS Convention （International Convention on the Control of Harmful Anti-fouling Systems in Ships） is a 2001 IMO （International Maritime Organization） treaty, whereby states agree to ban the use of harmful anti-fouling paints and other anti-fouling systems that contain harmful substances. Particularly, the use of the organotinTributyltin is prohibited, since leaching of that chemical from the hulls of ships has been shown to cause deleterious effects on some sea creatures. Although the AFS Convention has entered into force, its full implementation has not yet been appropriately achieved. Most of the ratifying States have delegated the Classification Society to inspect their ships to ensure the implementation of the provisions of the Convention. Since painting ships takes place in dry docks, the full control falls in the hands of Classification Societies.

关键词： Anti-fouling environment Tributyltin organotins biocide.

Assessment of Genetic Diversity of Argania spinosa L. Growing in Arid and Semi-arid Areas of Morocco as Revealed by Inter-Simple Sequence Repeats

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Journal of Agricultural Science and Technology(B) 2015年第5期5卷 336-346页

作者： Chaimaa Yatrib Bouchra Belkadi Ouafae Pakhrou Mohammed Alami Leila Medraoui Abdelhamid e1Mousadik Abderrahim Ferradous[ Fouad Msanda Cherkaoui e1 Modafar saad Ibn Souda-Kouraichi Abdelkarim Filali-Maltout Laboratory of Microbiology and Molecular Biology Department of Biology Mohammed V University Rabat 10000 Morocco 2Laboratory of Biotechnologies and Valuation of Natural Resources Department of Biology Ibn-Zohr University Agadir 80000Morocco High Commission for Water Forests and Desertification Control (HCEFLCD) Forestry Research Center (FRC) Marrakech40000 Morocco Laboratory of Biotechnology Valorization and Protection of Agro-resources Department of Biology Cadi Ayyad UniversityMarrakech 40000 Morocco Laboratory of Microbial Biotechnology Department of Biology Sidi Mohammed Ben Abdellah University Fez 30000 Morocco

Argania spinosa L. （Sapotaceae family）, endemic to Morocco, is a multipurpose tree with an important ecological and socio-economical interest. Nevertheless, the sustainability of the agro-forestry system is now threatened by overgrazing and over-exploitation leading to an alarming decline in the number of trees. In the present study, inter-simple sequence repeats （ISSR） markers were used to evaluate the genetic variation and to assess the genetic diversity distribution within and among 17 argan populations growing naturally under semi-arid and arid climate. Thus, a total of seven primers generated 260 well-defined bands, with an average of 37.14 bands per primer. Studied populations showed a relatively high level of genetic diversity at species level and low level of genetic diversity at population level. The percentage of polymorphic bands, Nei＇s gene diversity and Shannon＇s information index at population and species level were 30.15%, 0.164, 0.217 and 98.8%, 0.172, 0.293, respectively. A relative low level of genetic differentiation （Gst = 0.39） was in agreement with the results obtained from the analysis of molecular variance （AMOVA）. estimated gene flow was Nm = 0.781 among populations. Mantel test revealed a non-significant correlation between genetic and geographic distance （r = 0.065, P 〈 0.05）, suggesting that the geographic distribution is not the major factor that shaped the present population genetic structure. The results can help preserve A. spinosa L. tree as an endangered species, however, refining these finding using co-dominant markers is recommended in order to establish conservation strategies.

关键词： A. spinosa L. ISSR genetic diversity genetic differentiation gene flow.

A Comparative Study on the Performance and environmental Characteristics of Alternatives to R22 in Residential Air Conditioners for Tunisian Market

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Journal of environmental Science and engineering 2010年第12期4卷 37-56页

作者： M.C. Zaghdoudi S. Maalej Y. saad M. Bouchaala Laboratory Materials Measurements and Applications （MMA）-INSAT- University 7 November at Carthage Tunis Tunisia Medelim Company Ariana Tunisia

This paper presents the simulation results of a 9000 BTU/h air conditioner with some selected fluids that have been assessed for their suitability as alternatives to R22 for air conditioners. Only those refrigerants with zero Ozone Depletion Potential （ODP） are considered. The performances of 11 refrigerants were comparatively studied using the simulation software NIST Cycle_D. R134a, R290, R600, R404A, R407A, R407B, R407C, 407D, R410A, R410B, and R417A are considered in this study. The thermal performances, which are obtained with R 134a and R290, are very close to those of R22. The power consumptions of the unit operating with R404A, R407C, and R410A are higher in the range 22-31% with respect of R22. For the units operating with 407A, R407B, R407D, R407e, and R410B, the electric consumptions are higher in the range 10-23%. For R600, the power consumptions are in the range 6-8%. For all the fluids, the COP is lower by 7-24% than R22, except for R600 for which the COP is higher by 7-9%, and R134a and R290 which exhibit the same COP as R22. When considering the thermal and environmental parameters, R290 is identified as the best candidate for R22, provided the safety aspects of using R290 are addressed.

关键词： Air conditioner refrigerant replacement simulation performance COP

In vitro inhibitory analysis of consensus siRNAs against NS3 gene of hepatitis C virus 1a genotype

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Asian Pacific Journal of Tropical Medicine 2017年第7期10卷 763-770页

作者： Imran Shahid Waleed Hassan Al Malki Mohammed Wanees Al Rabia Mohammed Hasan Mukhtar Shaia Saleh R.Almalki saad Ahmed Alkahtani Sami S.Ashgar Hani S.Faidah Muhammad Hassan Hafeez Department of Pharmacology and Toxicology College of PharmacyUmm Al Qura University Department of Medical Microbiology College of MedicineKing Abdul Aziz University Department of Biochemistry Faculty of MedicineUmm Al Qura University Department of Laboratory Medicine Faculty of Applied Medical SciencesAlbaha University College of Pharmacy Najran University Department of Microbiology College of MedicineUmm Al Qura University Department of Gastroenterology and Hepatology Fatima Memorial College of Medicine and Dentistry

Objective: To explore inhibitory effects of genome-specific, chemically synthesized siRNAs(small interference RNA) against NS3 gene of hepatitis C virus(HCV) 1a genotype in stable Huh-7(human hepatoma) cells as well as against viral replication in serum-inoculated Huh-7 cells. Methods: Stable Huh-7 cells persistently expressing NS3 gene were produced under antibiotic gentamycin(G418) selection. The cell clones resistant to 1 000 μg antibiotic concentration(G418) were picked as stable cell clones. The NS3 gene expression in stable cell clone was confirmed by RT-PCR and Western blotting. siRNA cell cytotoxicity was determined by MTT cell proliferation assay. Stable cell lines were transfected with sequence specific siRNAs and their inhibitory effects were determined by RT-PCR, real-time PCR and Western blotting. The viral replication inhibition by siRNAs in serum inoculated Huh-7 cells was determined by real-time PCR. Results: RT-PCR and Western blot analysis confirmed NS3 gene and protein expression in stable cell lines on day 10, 20 and 30 post transfection. MTT cell proliferation assay revealed that at most concentrated dose tested(50 nmol/L), siRNA had no cytotoxic effects on Huh-7 cells and cell proliferation remained unaffected. As demonstrated by the siRNA time-dependent inhibitory analysis, siRNA NS3-is44 showed maximum inhibition of NS3 gene in stable Huh-7 cell clones at 24(80%, P=0.013) and 48 h(75%, P=0.002) post transfection. The impact of siRNAs on virus replication in serum inoculated Huh-7 cells also demonstrated significant decrease in viral copy number, where siRNA NS3-is44 exhibited 70%(Peduction as compared to NS3-is33, which showed a 64%(Pecrease in viral copy number. siRNA synergism(NS3-is33 + NS3-is44) decreased viral load by 84%(Ped to individual inhibition by each siRNA(i.e., 64%–70%(Perum-inoculated cells. Synthetic siRNAs mixture(NS5Bis88 + NS3-is33) targeting different region of HCV genom

关键词： Hepatitis C virus NS3 protein Stable Huh-7 cell culture system RNA interference NS5B HCV therapeutics