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Performance Evaluation of Bottom-Standing Submerged Breakwaters in Regular Waves Using the Meshless Singular Boundary Method

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Journal of Ocean University of China 2019年第4期18卷 823-833页

作者： SENOUCI Fawzi CHIOUKH Nadji DRIS mohammed el-amine Department of Hydraulics University Djillali Liabes of Sidi Bel-Abbes Sidi Bel-Abbes 22000 Algeria Laboratory of Naval Aero-Hydrodynamics USTO MB Oran 31000 Algeria Laboratory of Civil Engineering and Environment University Djillali Liabes of Sidi Bel-Abbes Sidi Bel-Abbes 22000 Algeria

In this paper, the improved version of the meshless singular boundary method (ISBM) is developed for analyzing the hydrodynamic performance of bottom-standing submerged breakwaters in regular normally incident waves. Both the single and dual prismatic breakwaters of rectangular and trapezoidal forms are examined. Only the impermeable breakwaters are considered in this study. The physical problem is cast in terms of the Laplace equation governing an irrotational flow and incompressible fluid motion with the appropriate mixed-type boundary conditions, and it is solved numerically using the ISBM. The numerical results are presented in terms of the hydrodynamic quantities of reflection and transmission coefficients. The values are first validated against the data of previous studies, computed, and discussed for a variety of structural conditions, including the height, width, and spacing of breakwater submergence. An excellent agreement is observed between the ISBM results and those of other methods. The breakwater width is found to feature marginal effects compared with the height. The present method is shown to accurately predict the resonant conditions at which the maximum reflection and transmission occur. The trapezoidal breakwaters are found to generally present a wide spectrum of reflections, suggesting that they would function better than the rectangular breakwaters. The dual breakwater systems are confirmed to perform much better than single structures.

关键词： meshless improved singular boundary method regular normal waves rectangular and trapezoidal breakwaters reflection transmission

RING OPENING POLYMERIZATION OF TETRAHYDROFURAN CATALYSED BY MAGHNITE-H^+

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Chinese Journal of Polymer Science 2012年第1期30卷 56-62页

作者： Khadidja Benkenfoud amine Harrane mohammed Belbachir Laboratoire de Chimie des Polymeres Departement de Chimie Faculte des SciencesUniversite d'Oran Es-SeniaBP No 1524 El M'Naouar31000 OranAlgeria

The cationic ring-opening polymerization of tetrahydrofiiran using maghnite-H~＋ is ***-H~＋,is a non-toxic solid catalyst issued from proton exchanged montmorillonite ***,also called ＂poly（butandiol） ether＂,with acetate and hydroxyl end groups was successfully *** of reaction temperature, weight ratio of initiator/monomer and reaction time on the conversion of monomer and on the molecular weight are investigated.A cationic mechanism of the reaction was *** chemistry can be considered as a suitable route for preparing poly（THF） as a soft segment for thermoplastic elastomers.

关键词： Montmorillonite Maghnite Ring opening polymerization THF

Modelling the monthly hydrological balance using Soil and Water Assessment Tool(SWAT)model:A case study of the Wadi Mina upstream watershed

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Journal of Groundwater Science and Engineering 2024年第2期12卷 161-177页

作者： Hanane Mebarki Noureddine Maref mohammed el-amine Dris Civil Engineering and Environmental Laboratory(LGCE) University of Djillali LiabèsFaculty of TechnologyHydraulics departmentBen M'Hidi districtP.O.Box 8922000Sidi Bel AbbèsAlgeria.

Modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and *** study aims to model the monthly hydrological water cycle in the Wadi Mina upstream watershed(northwest Algeria)by applying the Soil and Water Assessment Tool(SWAT)hydrological *** modelling integrates spatial data such as the Digital elevation Model(DEM),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind *** SWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from September 2013 to December *** and parameter calibration were conducted using the SWAT-SA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-Sutcliffe Efficiency(NSE),coefficient of determination(R2)and Percent Bias(PBAIS).Calibration results indicated favourable objec-tive function values(NSE=0.79,R2=0.93,PBAIS=-8.53%),although a slight decrease was observed during validation(NSE=0.69,R2=0.86,and PBAIS=-11.41%).The application of the SWAT model to the Wadi Mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this *** SWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.

关键词： SWAT model Performance Parameters Runoff Groundwater Wadi

Antimycobacterial natural products from Moroccan medicinal plants: Chemical composition, bacteriostatic and bactericidal profile of Thymus satureioides and Mentha pulegium essential oils

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Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 836-840页

作者： Marwa Chraibi Abdellah Farah Sara Lebrazi Oumaima el amine mohammed Iraqui Houssaini Kawtar Fikri-Benbrahim Laboratory of Microbial Biotechnology Faculty of Science and Technology Sass Sidi Mohamed Ben Abdellah University Laboratory of Aromatic Plants Medicinal and Natural Substances National Institute of Medicinal and Aromatic PlantsPhytochemistry Department

Objective: To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides(T. satureioides) and Mentha pulegium(M. pulegium), and to study their chemical ***: The aerial parts of T. satureioides and M. pulegium(leaves and stems) were hydro-distillated using a Clevenger-type apparatus and essential oils were analyzed and identified by gas chromatography-mass spectrometry. Antimycobacterial screening of essential oils was performed on the basis of the inhibition zone diameter by disc diffusion method against two mycobacterial strains whereas the minimal inhibitory concentration and minimal bactericidal concentration were determined by using the micro-dilution ***: Chemical analysis of their aerial part's essential oils gave as major compounds,borneol(34.26%), carvacrol(31.21%) and thymol(3.71%) for T. satureioides and R(+)-pulegone(75.48%), carvone(6.66%) and dihydrocarvone(4.64%) for M. *** their antimycobacterial effect evaluation, using the micro-dilution method,indicated that minimal inhibitory concentration values of T. satureioides essential oil ranged from 0.062% to 0.015%(v/v) and from 0.125% to 0.031%(v/v) for M. pulegium respectively against Mycobacterium aurum and Mycobacterium ***: It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug.

关键词： Thymus satureioides Mentha pulegium Essential oil Chemical composition Antimycobacterial activity

The current state of the plant diversity in the Tlemcen region(Northwest Algeria)

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Open Journal of Ecology 2012年第4期2卷 244-255页

作者： Smain el-amine Henaoui mohammed Bouazza Department of Biology and Environment Faculty of Natural Sciences and Life and Earth Sciences and the UniverseUniversity of TlemcenTlemcenAlgeria

Tlemcen region is characterized by a Mediterranean climate, with a remarkable vegetal cover. The latter is influenced by the anthropozoological action. For that, we realized a phytoecological study based on the minimum area classical method [1] which allows us to have a good overview on plant biodiversity and better analyze and interpret the vegetation at different levels (systematic composition;biological, morphological and biogeographical characterizations;stratification;and plant species inventory which we hope comprehensive). The results show that our ecosystems are disrupted because therophytisation, before last vegetation dynamics element [2], settles giving up a few feet of cork and holm oaks species of ancient forest.

关键词： Phytoecology Plant Diversity Minimum Area Anthropic Action Tlemcen(Western Algeria)

Synthesis, spectral, optical and anti-inflammatory activity of complexes derived from 2-aminobenzohydrazide with some rare earths

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Journal of Rare Earths 2015年第7期33卷 758-764页

作者： Nasser mohammed Hosny el Sayed A.el Morsy Yousery E.Sherif Chemistry Department Faculty of Science Port-Said University Clinical Pharmacology Department Faculty of Medicine Mansoura University Pharmacology and Therapeutics Department Qassim College of Medicine Qassim University Department of Chemistry Faculty of Science and Arts Taibah University

Three new metal complexes derived from Er（Ⅲ）, Dy（Ⅲ） and Zr（Ⅳ） with 2-aminobenzohydrazide （ABH） were synthesized and characterized by elemental analyses, IR, ^1H-NMR, ES-MS and transmission electron microscopy （TEM）. The morphology and the particle size were determined by TEM. The results showed that the ligand acted as neutral bi-dentate coordinating to the metal ions through the carbonyl oxygen and amidic amino nitrogen. The aromatic amine group remained inert towards coordination. The optical band gap was measured and found to be 3.3, 3.5 and 4.3 eV for Er（Ⅲ）, Dy（Ⅲ） and Zr（Ⅳ）, respectively. The optical band gap values indicated a semi-conducting nature of the investigated complexes. The anti-inflammatory and analgesic activities of the tested compounds were determined and compared with standard meloxicam.

关键词： Er(Ⅲ) Dy(Ⅲ) Zr(Ⅳ) metal complexes optical band gap rare earths

Emotion processing in Parkinson's disease: a blood oxygenation level-dependent functional magnetic resonance imaging study

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Neural Regeneration Research 2019年第4期14卷 666-672页

作者： mohammed Benzagmout Sa?d Boujraf Badreeddine Alami Hassane Ali Amadou Halima el Hamdaoui amine Bennani Mounir Jaafari Ismail Rammouz Mustapha Maaroufi Rabia Magoul Driss Boussaoud Laboratory of Clinical Neuroscience Faculty of Medicine Department of Neurosurgery University Hospital of Fez Laboratory of Neuroendocrinology and Nutritional and Climatic Environment Faculty of Sciences Dhar El Mahraz Department of Biophysics and Clinical MRI Methods Faculty of Medicine Department of Radiology and Clinical Imaging University Hospital of Fez Department of Psychiatry University Hospital of Fez Aix Marseille Université INSERM INS Institut de Neurosciences des Systèmes

Parkinson's disease is a neurodegenerative disorder caused by loss of dopamine neurons in the substantia nigra pars compacta. Tremor, rigidity, and bradykinesia are the major symptoms of the disease. These motor impairments are often accompanied by affective and emotional dysfunctions which have been largely studied over the last decade. The aim of this study was to investigate emotional processing organization in the brain of patients with Parkinson's disease and to explore whether there are differences between recognition of different types of emotions in Parkinson's disease. We examined 18 patients with Parkinson's disease(8 men, 10 women) with no history of neurological or psychiatric comorbidities. All these patients underwent identical brain blood oxygenation level-dependent functional magnetic resonance imaging for emotion evaluation. Blood oxygenation level-dependent functional magnetic resonance imaging results revealed that the occipito-temporal cortices, insula, orbitofrontal cortex, basal ganglia, and parietal cortex which are involved in emotion processing, were activated during the functional control. Additionally, positive emotions activate larger volumes of the same anatomical entities than neutral and negative emotions. Results also revealed that Parkinson's disease associated with emotional disorders are increasingly recognized as disabling as classic motor symptoms. These findings help clinical physicians to recognize the emotional dysfunction of patients with Parkinson's disease.

关键词： Parkinson’s disease emotion processing Blood oxygenation level-dependent functional magnetic resonance imaging brain activation dopamine neural regeneration

Small inhibitors of ADP-ribosylation factor activation and function in mammalian cells

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World Journal of Pharmacology 2012年第4期1卷 55-64页

作者： Sylvain G Bourgoin mohammed-amine el Azreq Centre de Recherche en Rhumatologie et Immunologie Centre de Recherche du CHUQ-CHUL Quebec G1V 4G2 Canada Département de Microbiologie-Infectiologie et Immunologie Faculté de Médecine Université Laval Quebec G1V 4G2 Canada

Small GTP-binding proteins of the ADP-ribosylation fac-tor （Arf） family control various cell functional responses including protein transport and recycling between different cellular compartments, phagocytosis, prolif-eration, cytoskeletal remodelling, and migration. The activity of Arfs is tightly regulated. GTPase-activating proteins （GAPs） inactivate Arfs by stimulating GTP hydrolysis, and guanine nucleotide exchange factors （GEFs） stimulate the conversion of inactive GDP-bound Arf to the active GTP-bound conformation. There is increasing evidence that Arf small GTPases contribute to cancer growth and invasion. Increased expression of Arf6 and of Arf-GEPs, or deregulation Arf-GAP functions have been correlated with enhanced invasive capacity of tumor cells and metastasis. The spatiotemporal spe-cifcity of Arf activation is dictated by their GEFs that integrate various signals in stimulated cells. Brefeldin A （BFA）, which inactivates a subset of Arf-GEFs, has been very useful for assessing the function of Golgi-localized Arfs. However, specifc inhibitors to investigate the individual function of BFA-sensitive and insensitive Arf-GEFs are lacking. In recent years, specifc screens have been developed, and new inhibitors with improved se-lectivity and potency to study cell functional responses regulated by BFA-sensitive and BFA-insensitive Arf pathways have been identified. These inhibitors have been instrumental for our understanding of the spa-tiotemporal activation of Arf proteins in cells and dem-onstrate the feasibility of developing small molecules interfering with Arf activation to prevent tumor invasion and metastasis.

关键词： Golgi Vesicular transport Migration Adhe-sion Actin

Enhancing Hygrothermal Performance in Multi-Zone Constructions through Phase Change Material Integration

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Frontiers in Heat and Mass Transfer 2024年第3期22卷 769-789页

作者： Abir Abboud Zakaria Triki Rachid Djeffal Sidi mohammed el amine Bekkouche Hichem Tahraoui Abdeltif Amrane Aymen Amin Assadi Lotfi Khozami Jie Zhang Laboratory of Biomaterials and Transport Phenomena University of MedeaMedea26000Algeria Unitéde Recherche Appliquée en Energies Renouvelables(URAER)Centre de Développement des Energies Renouvelables(CDER) Ghardaia47133Algeria Laboratoire de Génie des Procédés Chimiques Department of Process EngineeringUniversity of Ferhat AbbasSetif19000Algeria Universitéde Rennes Ecole Nationale Supérieure de Chimie de RennesCNRSISCR-UMR6226Rennes35000France College of Engineering Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia School of Engineering Merz CourtNewcastle UniversityNewcastle upon TyneNE17RUUK

As buildings evolve to meet the challenges of energy efficiency and indoor comfort,phase change materials(PCM)emerge as a promising solution due to their ability to store and release latent *** paper explores the transformative impact of incorporating PCMon the hygrothermal dynamics of multi-zone *** study focuses on analyzing heat transfer,particularly through thermal conduction,in a wall containing PCM.A novel approach was proposed,wherein the studied system(sensitive balance)interacts directly with a latent balance to realistically define the behavior of specific humidity and mass flow *** addition,a numerical model implemented in MATLAB software has been developed to investigate the effect of integrating PCM on the hygrothermal balances inside the *** obtained results indicate a consistent response in internal temperatures,specific humidity,and mass flow rates,with temperature differences ranging from 5℃to 13℃and a maximum phase shift of 13 *** addition,the findings provided valuable insights into optimizing the design and performance of multi-zone constructions,offering a sustainable pathway for enhancing building resilience and occupant well-being.

关键词： Multi-zone constructions phase changematerial hygrothermal balances heat transfer thermal conduction energy efficiency