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Structural,morphological and photoluminescence characterizations of Sm^(3+) doped Y_(2)O_(3) nano-sized phosphors synthesized by ultrasound assisted sol-gel method

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Journal of Rare Earths 2023年第1期41卷 51-59页

作者： Lyes Lamiri Badis Kahouadji Mourad Berd Abdelmoumen Abdellatif Lotfi Benchallal Lakhdar Guerbous Salim Ouhenia abdelhafid souici Leila Amiour Abdelhalim Zoukel Madani Samah Department of TCSN University of BejaiaBejaia06000Algeria Department of Technology University of BejaiaBejaia06000Algeria Department of Technology Laboratory of LECVEUniversity of BejaiaBejaiaO6000Algeria Department of Physics of Materials University of Science and Technology Houari BoumedieneAlgiersAlgeria Laser Department/Nuclear Research Center of Algiers(CRNA) 02Boulevard Frantz FanonB.P.399Algiers16000Algeria Laboratory of Physical-chemistry University of BejaiaBejaia06000Algeria Phase Transformation Laboratory Universite Freres Mentouri Constantine 1Algeria Laboratory Physico-Chemistry of Materials Laghouat UniversityTechnical Platform of Physico-Chemical Analysis(PTAPC-Laghouat-CRAPC)LaghouatAlgeria

Nanosized 1 at% Sm^(3+)doped Y_(2)O_(3)powders were prepared by an ultrasound assisted sol-gel method.Y_(2)O_(3):Sm^(3+)powders crystallize in Y_(2)O_(3)pure cubic phase and XRD analysis shows that the as-used agitation protocol affects strongly the crystallite’s shape and mean *** recorded emission spectra under λ_(em)=600 nm exhibit two absorption bands;the first one is assigned to O^(2-)→Sm^(3+)charge transfer state(CTS) with a maximum absorption at 223 nm,and the second is due to intraconfigurational transition 4f^(5)-4f^(5) of Sm^(3+) with a maximum absorption at 407 *** 223 and 407 nm transitions are attributed to characteristics intra-configurational transitions of Sm^(3+).All emission spectra are dominated by reddish/orange luminescence located at 606 nm and assigned to ^(4)G_(5/2)→^(6)H_(7/2) *** is found that the photoluminescence intensity of samples obtained under excitation at 407 nm is 60 times smaller than that obtained under 223 nm *** time measurements of the ^(4)G_(5/2)→^(6)H_(7/2) luminescence transition indicate that decay time of nano-sized powder is significantly shorter than bulk material one.

关键词： Y_(2)O_(3):Sm^(3+)nano-sized powder Sol-gel method Ultrasound Charge transfer Photoluminescence Rare earths

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Prediction of the theoretical and semi-empirical model of ambient temperature

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Frontiers in Energy 2016年第3期10卷 268-276页

作者： Foued CHABANE Noureddine MOUMMI abdelhafid BRIMA abdelhafid MOUMMI Mechanical Department Mechanical Engineering Laboratory (LGM)Faculty of Technology University of Biskra Biskra 07000 Algeria

It is well known that the ambient temperature is a sensitive parameter which has a great effect on biology, technology, geology and even on human behavior. A prediction is a statement about an uncertain event. It is often, but not always, based upon experience or knowl- edge. Although guaranteed accurate information about the future is in many cases impossible, prediction can be useful to assist in making plans about possible developments. As a result, temperature profiles can be developed which accurately represent the expected ambient temperature exposure that this environment experiences during mea- surement. The ambient temperature over time is modeled based on the previous Train and Tmax data and using a Lagrange interpolation. To observe the comprehensive variation of ambient temperature the profile must be determined numerically. The model proposed in this paper can provide an acceptable way to measure the change in ambient temperature.

关键词： ambient temperature environment correlation theoretical model semi-empirical

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A Piecewise Switched Linear Approach for Traffic Flow Modeling

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International Journal of Automation and computing 2017年第6期14卷 729-741页

作者： abdelhafid Zeroual Nadhir Messai Sihem Kechida Fatiha Hamdi Laboratory of Automatic and Informatics LAIGUniversity of 08 May 1945Guelma 24000Algeria CReSTiC-URCA UFR SEN University of Reims Champagne-ArdenneMoulin de la HousseBP 1039 51687 Reims Cedex 2France Department of Electronics Center ABROUK MadaniUniversity of Batna 205 Avenue Chahid Boukhlouf 05000 BatnaAlgeria

Traffic modeling is a key step in several intelligent transportation systems（ITS） applications. This paper regards the traffic modeling through the enhancement of the cell transmission model. It considers the traffic flow as a hybrid dynamic system and proposes a piecewise switched linear traffic model. The latter allows an accurate modeling of the traffic flow in a given section by considering its geometry. On the other hand, the piecewise switched linear traffic model handles more than one congestion wave and has the advantage to be modular. The measurements at upstream and downstream boundaries are also used in this model in order to decouple the traffic flow dynamics of successive road portions. Finally, real magnetic sensor data, provided by the performance measurement system on a portion of the Californian SR60-E highway are used to validate the proposed model.

关键词： Switched systems modeling macroscopic traffic flow data calibration

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Use of genetic algorithm in new approach to modeling of flood routing

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Journal of Oceanology and Limnology 2019年第1期37卷 72-78页

作者： EL ALAOUI EL FELS abdelhafid ALAA Noureddine BACHNOU Ali Laboratory of Geosciences and Environnement Department of Earth Sciences Faculty of Science and Technics Gueliz (P. B. 549) Cadi Ayyad University Laboratory Applied Mathematics and Informatics Department of Math and Informatics Faculty of Science and Technics Gueliz (P. B. 549) Cadi Ayyad University

The hydrological models and simpli?ed methods of Saint-venant equations are used extensively in hydrological modeling, in particular for the simulation of the ?ood routing. These models require speci?c and extensive data that usually makes the study of ?ood propagation an arduous practice. We present in this work a new model, based on a transfer function, this function is a function of parametric probability density, having a physical meaning with respect to the propagation of a hydrological signal. The inversion of the model is carried out by an optimization technique called Genetic Algorithm. It consists of evolving a population of parameters based primarily on genetic recombination operators and natural selection to?nd the minimum of an objective function that measures the distance between observed and simulated data. The precision of the simulations of the proposed model is compared with the response of the Hayami model and the applicability of the model is tested on a real case, the N'Fis basin river, located in the High Atlas Occidental, which presents elements that appear favorable to the study of the propagation. The results obtained are very satisfactory and the simulation of the proposed model is very close to the response of the Hayami model.

关键词： Genetic Algorithm flood routing Hayami model simulation propagation

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Antioxidant activity profiling by spectrophotometric methods of aqueous methanolic extracts of Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile

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Chinese Journal of Natural Medicines 2014年第6期12卷 415-422页

作者： Farah Haddouchi Tarik Mohammed Chaouche Riadh Ksouri Faten Medini Fatima Zohra Sekkal abdelhafid Benmansour Laboratory of Natural Products Department of Biology Faculty of Sciences Abou Bekr Belkad University Laboratory of Plant Adaptation to Abiotic Stresses Biotechnologic Center in Borj-Cedria Technopol (CBBC) Department of Biotechnology Faculty of Natural Science and Life Abdelel Hamid Ibn Badiss University Mostaganem 27000 Algeria

AIM: The aqueous methanolic extracts of two plants from Algeria, Helichrysum stoechas subsp. rupestre and Phagnalon saxatile subsp. saxatile, were investigated for their antioxidant activity. METHOD: Total phenolics, flavonoids, and tannins were determined by spectrophotometric techniques..In vitro antioxidant and radical scavenging profiling was determined by spectrophotometric methods, through: Total antioxidant capacity, and radical scavenging effects by the DPPH and ABTS methods, reducing and chelating power, and blanching inhibition of the β-carotene. RESULTS: All of the extracts showed interesting antioxidant and radical scavenging activity. The highest contents in phenolics, tannins, and the highest total antioxidant capacity as gallic acid equivalents of 97.5 ± 0.33 mg GAE/g DW was obtained for the flowers of H. stoechas subsp. rupestre extract in the phosphomolybdenum assay. An extract of the leafy stems of P. saxatile subsp. saxatile revealed the highest content of flavonoids, and the highest antioxidant activity by the radical scavenging and β-carotene assays when compared with standards. The best activity was by the scavenging radical DPPH with an IC50 value of 5.65 ± 0.10 μg·mL-1. CONCLUSION: The studied medicinal plants could provide scientific evidence for some traditional uses in the treatment of diseases related to the production of reactive oxygen species(ROS) and oxidative stress.

关键词： Helichrysum stoechas subsp.rupestre Phagnalon saxatile subsp.saxatile Phenolic compounds Antioxidant activity

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The haplotype-resolved T2T reference genome highlights structural variation underlying agronomic traits of melon

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Horticulture Research 2023年第10期10卷 12-24页

作者： Guoli Li Lingli Tang Yuhua He Yongyang Xu abdelhafid Bendahmane Jordi Garcia-Mas Tao Lin Guangwei Zhao National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops Zhengzhou Fruit Research InstituteChinese Academy of Agricultural SciencesZhengzhouHenan 450009China China Agricultural University College of HorticultureBeijing 100193China National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanyaHainan 572024China Zhongyuan Research Center Chinese Academy of Agricultural SciencesXinxiang 453400China Institute of Plant Sciences Paris-Saclay(IPS2) INRAECNRSUniversity of Paris-SaclayUniversity of EvryUniversity of Paris-DiderotGif sur Yvette 91192France Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB Edifici CRAGCampus UABBellaterra08193 BarcelonaSpain Institut de Recerca i Tecnologia Agroalimentàries(IRTA) Edifici CRAGCampus UABBellaterra08193 BarcelonaSpain

Melon(Cucumis melo L.)is an important vegetable crop that has an extensive history of ***,the genome of wild and semi-wild melon types that can be used for the analysis of agronomic traits is not yet *** we report a chromosome-level T2T genome assembly for 821(*** *** ***),a semi-wild melon with two haplotypes of∼373 Mb and∼364 Mb,*** genome analysis discovered a significant number of structural variants(SVs)between melo(*** ***)and agrestis(*** ***)genomes,including a copy number variation located in the ToLCNDV resistance locus on chromosome ***-wide association studies detected a significant signal associated with climacteric ripening and identified one candidate gene CM_ac12g14720.1(CmABA2),encoding a cytoplasmic short chain dehydrogenase/reductase,which controls the biosynthesis of abscisic *** study provides valuable genetic resources for future research on melon breeding.

关键词： agronomic traits structural

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Environmental Impact of Mining Exploitation: A Case Study of Some Mines of Barite in the Eastern Anti-Atlas of Morocco

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Journal of Environmental Protection 2016年第11期7卷 1473-1482页

作者： abdelhafid Essalhi Mourad Essalhi Abdeslam Toummite Equipe de Recherche: Géophysique Géoressources et Patrimoine (ER-GGP) Département de Géologie Faculté des Sciences et Techniques Errachidia Maroc

Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of the exploitation sites. In this study performed on some mining areas of the Moroccan Anti-Atlas, four principal negative effects were detected: effect on the physiognomy, on safety, on health, and on recovery rate. The principal source of this situation is the exploitation of the ore deposits from top to bottom without using any geological preparation and the use of non-adapted exploitation technics. To minimize these impacts, we propose to establish a geological study and advanced mining exploration before starting exploitation, and follow an exploitation technic well adapted to the morphology of the ore deposit like cut-and-fill mining and sublevel stoping methods.

关键词： Negative Impacts Environment Exploitation Physiognomy Anti-Atlas

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Clinical Analysis of 42 Patients With Hypertrophic Cardiomyopathy

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South China Journal of Cardiology 2007年第1期8卷 17-26页

作者： Kebbati abdelhafid 伍卫刘泽生 Department of Cardiovascular disease Second Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510120 China

Objectives To investigate the clinical manifestations of hypertrophic cardiomyopathy (HCM), and to find out the clinical clues to avoid misdiagnosis and provide reference for future clinical diagnosis and treatment. Methods A retrospective analysis of 42 consecutive patients with HCM hospitalized in our hospital between January 1995 and December 2002 was explored. Based on the family history of HCM, clinical manifestations, electrocar-diogram, echocardiogram, coronary angiography and left ventriculography, the clinical characteristics between HCM patients with left ventricular outflow tract obstruction (HOCM) and HCM patients without obstruction (HNOCM) were compared. The causes of misdiagnosis and losing diagnosis were analysis. Results 13 patients were in HOCM group and 29 patients were in HNOCM group. More patients with syncope were in HOCM group than in HNOCM group (6/13 vs. 2/29, P < 0.05). Patients with ejective murmur were in HOCM group only (P < 0.01). Left ventricular outflow tract pressure gradient (LVOTPG) only observed in HOCM group (P < 0.01). Ventricular tachycardia was seen in both groups. 28 out of 42 patients (66.67%) had misdiagnosis, and 4 out of 42 patients (9.53%) had losing diagnosis. Thus, coronary heart disease (CHD) had the highest rate of misdiagnosis. There were 20 CHD patients (71.43%) among 28 patients with misdiagnosis. Hypertension was in 3, congenital heart in 2, cerebro-embolism in 2, and myocarditis in 1. Conclusions For a patient with family history or sudden death history of HCM, unexplained syncope episodes, chest pain (angina), especially in young, an ejection murmur along the left sternum border, the presence of narrow and deep Q waves, or inversion of giant T waves in V3-V6, atrial fibrillation and /or cerebra-embolism echocardiogram should be given. CAG and LVG are necessary only if the result of echo is negative, and the patients with suspected HCM or CHD.

关键词： Cardiomyopathy Hypertrophic Analysis Retrospective Clinical

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PALSAR-FBS L-HH Mode and Landsat-TM Data Fusion for Geological Mapping

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Advances in Remote Sensing 2016年第4期5卷 246-268页

作者： Abderrazak Bannari Ali El-Battay Ali Saquaque abdelhafid Miri Department of Geoinformatics Arabian Gulf University Manama Kingdom of Bahrain Managem Mineral ONA Group Twin Center Casablanca Kingdom of Morocco

Characterized by lithological diversity and rich mineral resources, Benshangul-Gumuz National Regional State located in Asosa Zones, Western Ethiopia has been investigated for geological mapping and morpho-structural lineaments extraction using PALSAR (Phased Array type L-band Synthetic Aperture Radar ) Fine Beam Single (FBS) L-HH polarization and Landsat-5 TM (Thematic Mapper ) datasets. These data were preprocessed to retrieve ground surface reflectance and backscatter coefficients. To overcome the geometry acquisition between the two sensors, they were geometrically and topographically rectified using ASTER-V2 DEM. Intensity-Hue-Saturation, directional filters and automatic lineaments extraction were applied on the datasets for lithological units’ discrimination and structural delimitation for potential mineral exploration. The obtained results showed good relationship among the topographic morphology, rock-substrate, structural variations properties, and drainage network. The spectral variations were easily associated with lithological units. Likewise, the morpho-structural information highlighted in the PALSAR image was visible without altering the radiometric integrity of the details in TM bands through the fusion process. Moreover, predominant lineaments directions trending NE-SW, NS, and NW-SE were identified. Results of this study highlighted the importance of the PALSAR FBS L-HH mode and TM data fusion to enhance geological features and lithological units for mineral exploration particularly in tropical zones.

关键词： Geology Mineral Exploration Lineaments Extraction Data Fusion Intensity-Hue-Saturation Mapping Landsat-TM PALSAR-FBS L-HH Polarization ASTER DEM

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The miR166-SIHB15A regulatory module controls ovule development and parthenocarpic fruit set under adverse temperatures in tomato

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Molecular Plant 2021年第7期14卷 1185-1198页

作者： Christian Clepet Ravi Sureshbhai Devani Rachid Boumlik Yanwei Hao Halima Morin Fabien Marcel Marion Verdenaud Brahim Mania Gwilherm Brisou Sylvie Citerne Gregory Mouille Jean-Christophe Lepeltier Shai Koussevitzky Adnane Boualem abdelhafid Bendahmane Institute of Plant Sciences Paris-Saclay INRAECNRSUniversite Paris-SaclayOrsay 91405France HM Clause Mas Saint-PierreQuartier La GalineSaint-Remy de Provence 13210France Hazera Seeds Ltd Berurim M.P.Shikmim 7983700Israel lnstitut Jean-Pierre Bourgin INRAEVersaillesFrance Present address:Key Laboratory of Horticultural Crop Biology and Germplasm Innovation in South China College of HorticultureSouth China Agricultural UniversityGuangzhou 510642China

Fruit set is inhibited by adverse temperatures,with consequences on *** isolated a tomato mutant producing fruits under non-permissive hot temperatures and identified the causal gene as SIHB15A,belonging to classⅢhomeodomain leucine-zipper transcription ***15A,loss-of-function mu-tants display aberrant ovule development that mimics transcriptional changes occurring in fertilized ovules and leads to parthenocarpic fruit set under optimal and non-permissive temperatures,in field and greenhouse *** cold growing conditions,SIHB15A is subjected to conditional haploinsufficiency and recessive dosage sensitivity controlled by microRNA 166(miR166).Knockdown of SIHB15A alleles by miR166 leads to a continuum of aberrant ovules correlating with parthenocarpic fruit *** with this,plants harboring an Slhb15a-miRNA166-resisiant allele developed normal ovules and were unable to set parthenocarpic fruit under cold *** affinity purification sequencing and RNA-sequencing analyses revealed that SIHB15A is a bifunctional transcription factor expressed in the ovule ***15A binds to the promoters of auxin-related genes to repress auxin signaling and to the promoters of ethylene-related genes to activate their expression.A survey of tomato genetic biodiversity identified pat and pat-1,two historical parthenocarpic mutants,as alleles of *** together,our findings demonstrate the role of SIHB15A as a sentinel to prevent fruit set in the absence of fertilization and provide a mean to enhance fruiting under extreme temperatures.

关键词： parthenocarpy dosage sensitivity HD-Ziplll miRNA166 heat stress cold stress

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