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On M-theory on real toric fibrations

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Communications in Theoretical Physics 2021年第8期73卷 67-74页

作者： A Belhaj H Belmahi M Benali S-E Ennadifi Y Hassouni Y Sekhmani equipe des sciences de la matière et du rayonnement ESMaRDépartement de Physique Facultédes SciencesUniversitéMohammed V de RabatMorocco LHEP-MS Département de PhysiqueFaculte des SciencesUniversitéMohammed V de RabatMorocco

Borrowing ideas from elliptic complex geometry, we approach M-theory compactifications on real fibrations. Precisely, we explore real toric equations rather than complex ones exploited in F-theory and related dual models. These geometries have been built by moving real toric manifolds over real bases. Using topological changing behaviors, we unveil certain data associated with gauge sectors relying on affine lie symmetries.

关键词： real fibrations M-theory toric real manifolds affine lie symmetries

On stability behaviors of 5D M-theory black objects

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Communications in Theoretical Physics 2024年第5期76卷 94-101页

作者： Adil Belhaj Abderrahim Bouhouch departement de Physique Equipe des Sciences de la matiere et du rayonnementESMaR Faculte des SciencesUniversite Mohammed V de RabatRabatMorocco

Using N=2 supergravity formalism,we investigate certain behaviors of five-dimensional black objects from the compactification of M-theory on a Calabi-Yau *** manifold has been constructed as the intersection of two homogeneous polynomials of degrees(ω+2,1)and(2,1)in a product of two weighted projective spaces given by WP^(4)(ω,1,1,1,1)×P^(1).First,we determine the allowed electric charge regions of the BPS and non BPS black holes obtained by wrapping M2-branes on appropriate two cycles in such a proposed Calabi-Yau *** that,we calculate the entropy of these solutions which takes a maximal value corresponding to ω=1 defining the ordinary projective space P^(4).For generic values of ω,we show that the non BPS states are ***,we conduct a similar study of five-dimensional black *** the allowed magnetic charge regions of the BPS and non BPS black stringy solutions derived from M5-branes on dual divisors,we calculate the tension taking a minimal value for P^(4).By determining the recombination factor,we show that the non-BPS black string states are stable in the allowed regions in the magnetic charge space.

关键词： M-theory Calabi-Yau manifolds black holes black strings stability behaviors

D-term Chaotic Braneworld in Supergravity Constrained by WMAP9 Data

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Communications in Theoretical Physics 2014年第3期61卷 397-402页

作者： A.Safsafi M.Ferricha-Alami H.Chakir J.Inchaouh M.Bennai laboratoire de Physique de la matiére Condens'ee equipe Physique Quantique et Applications Facultédes Sciences BenM’sik B.P. 7955 Université Hassan II-Mohammedia laboratoire de recherche Subatomique et Applications Facultédes Sciences Ben M’sik B.P. 7955 UniversitéHassanII-Mohammedia laboratoire de Physique de la matiére Condens'ee equipe Physique Quantique et Applications Facultédes Sciences BenM’sik B.P. 7955 UniversitéHassan II-Mohammedia Groupement National de Physique des Hautes Energies Focal Point LabUFR-PHE

We study a supergravity D-term chaotic inflationary model, in the context of the braneworld scenario, in particular we consider the Randal1-Sundrum model type 2. Using the latest release from the combination of WMAP9, eCMB, BAO, and Ho, we show that the inflation observables depend only on the number ore-folds N. We also derive all known spectrum inflationary parameters, which are widely consistent with WMAP9 data for a particular choice of values N specially for the scalar spectral index ns and the ratio r. However, the running of the scalar spectral index dns/dlnk is now excluded from the range given by the latest observational measurements.

关键词： D-term chaotic braneworld perturbation spectrum WMAP9

Exploring the impact of weak measurements on exciton-exciton interactions

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Communications in Theoretical Physics 2024年第11期76卷 42-47页

作者： Fatima-Zahra Siyouri Olivier Giraud Yassine Hassouni equipe sciences de la matiere et du rayonnement(ESMaR) Departement de PhysiqueFaculte des SciencesUniversite Mohammed VAgdalAv.Ibn BattoutaB.P.1014AgdalRabatMorocco laboratoire de Physique Theorique et Modeles Statistiques(LPTMS) Faculte des sciencesUniversite parissaclayParisFrance

In our study of super quantum discord between two excitonic qubits inside a coupled semiconductor quantum dots system,our primary focus is to uncover the impact of weak measurement on its quantum *** achieve this,we analyze how varying the measurement strength x,affects this super quantum correlation in the presence of thermal ***,we assess the effect of this variation on the system's evolution against its associated quantum parameters;external electric fields,exciton-exciton dipole interaction energy and F?rster *** findings indicate that adjusting x to smaller values effectively enhances the super quantum correlation,making weak measurements act as a *** adjustment ensures its robustness against thermal effects while preserving the non-classical attributes of the ***,our study unveils that the effect of weak measurements on this latter surpasses the quantum effects associated with the ***,manipulating the parameter x allows the weak measurement to function as a versatile tool for modulating quantum characteristics and controlling exciton-exciton interactions within the coupled semiconductor quantum dots system.

关键词： super quantum discord weak measurements measurement strength x semiconductor quantum dots exciton-exciton interactions

deformation Characteristics and Tectonic Evolution of the Eastern Qinling Orogenic Belt

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Acta Geologica Sinica(English Edition) 1986年第3期60卷 23-35页

作者： M.Mattauer Ph.Matte J.Malavieille P.Tapponnier H.Maluski department des sciences de la Terre equipe Tectonique Université des sciences et Techniques du languedoc Place E. Bataillon 34060 Montpellier Cédex France. Department des Sciences de la Terre Equipe Tectonique Université des Sciences et Techniques du Languedoc Place E. Bataillon 34060 Montpellier Cédex France.Department des Sciences de la Terre Equipe Tectonique Université des Sciences et Techniques du Languedoc Place E. Bataillon 34060 Montpellier Cédex France.Institut de Physique du Globe 4 Place Jussieu 75230 Paris Cedex 05 France.Department des Sciences de la Terre Equipe Tectonique Université des Sciences et Techniques du Languedoc Place E. Bataillon 34060 Montpellier Cédex France.

The Qinling Mountains separating the northern from the southern China plate is a key region for the study of structural evolution of eastern Asia. It is composed of the Palaeozoic fold belt in its northern part and the Variscan and Indosinian fold belts in its southern part. The evolution of the former is marked by the closure of a northward subducting oceanic basin in the early stage, followed by southward obduction of ophiolites and intracontinental thrusting during the Variscan; whereas that of the latter is represented by intracontinental, shallow crustal deformation on the basis of a large-scale detachment structure(with a horizontal slip of at least of 100 km). Since the late Palaeozoic, however, both of the belts have been cut by a series of east-west sinistral strike-slip faults.

关键词： deformation Characteristics and Tectonic Evolution of the Eastern Qinling Orogenic Belt

Toric realisation of Quantum Systems via Clifford Structures

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Journal of Applied Mathematics and Physics 2022年第2期10卷 527-537页

作者： Mohammed Bensed Youssef El Maadi Département de Physique LabSIMO Faculté des Sciences Université Ibn Tofail Kénitra Morocco Département de Physique Equipe des Sciences de la matiére et du rayonnement ESMaR Faculté des Sciences Université Mohammed V de Rabat Rabat Morocco

We present a geometric approach to describe quantum information systems. Precisely, we elaborate a genuine correspondence between toric geometry and qubit systems using the construction of Clifford graph algebras. This mapping may be explored to investigate qubit information applications using toric geometry considered as a potent tool to understand high energy physics including black holes and string theory. Explicitly, we examine in some details the cases of two and three qubits, and we find that they are associated with certain Clifford graph structures. Mixed states are also discussed.

关键词： Qubit Information Systems Clifford Graph Algebras Toric Geometry

Neutron-gamma discrimination method based on blind source separation and machine learning

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Nuclear Science and Techniques 2021年第2期32卷 70-80页

作者： Hanan Arahmane El-Mehdi Hamzaoui Yann Ben Maissa Rajaa Cherkaoui El Moursli Universite´Paris-Saclay CEAList91120 PalaiseauFrance equipe des sciences de la matie`re et du rayonnement(ESMaR) Faculty of SciencesMohammed V University in RabatB.P.1014 RPRabatMorocco National Centre for Nuclear Energy Science and Technology(CNESTEN)B.P.1382 R.P.10001RabatMorocco laboratory of Telecommunications Networks and Service SystemsNational Institute of Posts and TelecommunicationsAllal El Fassi AvenueRabatMorocco

The discrimination of neutrons from gamma rays in a mixed radiation field is crucial in neutron detection *** approaches have been proposed to enhance the performance and accuracy of neutron-gamma ***,their performances are often associated with certain factors,such as experimental requirements and resulting mixed *** main purpose of this study is to achieve fast and accurate neutron-gamma discrimination without a priori information on the signal to be analyzed,as well as the experimental ***,a novel method is proposed based on two *** first method exploits the power of nonnegative tensor factorization(NTF)as a blind source separation method to extract the original components from the mixture signals recorded at the output of the stilbene scintillator *** second one is based on the principles of support vector machine(SVM)to identify and discriminate these *** addition to these two main methods,we adopted the Mexican-hat function as a continuous wavelet transform to characterize the components extracted using the NTF *** resulting scalograms are processed as colored images,which are segmented into two distinct classes using the Otsu thresholding method to extract the features of interest of the neutrons and gamma-ray components from the background *** subsequently used principal component analysis to select the most significant of these features wich are used in the training and testing datasets for ***-variance analysis is used to optimize the SVM model by finding the optimal level of model complexity with the highest possible generalization *** this framework,the obtained results have verified a suitable bias–variance trade-off *** achieved an operational SVM prediction model for neutron-gamma classification with a high true-positive *** accuracy and performance of the SVM based on the NTF was evaluated and validated by comparing it to the charge comparison

关键词： Blind source separation Nonnegative tensor factorization(NTF) Support vector machines(SVM) Continuous wavelets transform(CWT) Otsu thresholding method

Breaking seed dormancy in Cupressus atlantica Gaussen,an endemicand threatened coniferous tree in Morocco

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Journal of Forestry research 2012年第3期23卷 385-390页

作者： Sfairi Youssef Ouahmane lahcen Abbad Abdelaziz Direction Provinciale des Eaux et Forets et de la lutte contre laDésertification MarrakechMaroc laboratoire de Biotechnologies Protection et Valorisation des Ressources Végétalesdépartement deBiologieEquipe de Phytochimie et Pharmacologie des Plantes Aromatiques et MédicinalesFacultédes Sciences SemlaliaUniversitéCadi AyyadMarrakechMaroc Centre Régional de recherche Forestière Circuit de la PalmeraieMarrakechMaroc laboratoire de Biotechnologies Protection et Valorisation desRessources Végétalesdépartement de BiologieEquipe de Phytochimieet Pharmacologie des Plantes Aromatiques et MédicinalesFacultédesSciences SemlaliaUniversitéCadi AyyadMarrakechMaroc

Cupressus atlantica Gaussen （Cupressaceae） is an endemic and endangered coniferous tree geographically restricted to the N＇Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dormancy which delays and reduces germination. To improve seed germination, different pre-treatments were conducted on C. atlantica seeds after storage for different periods （one, two and five years） including： scarification with sandy paper; soaking seeds in hot distilled water at 60℃ and 80℃ for 15 min and soaking seeds for 48 h in a gibberellic acid （GA3） at 1,000 and 2,000 mg·L-1. results showed that scarification with sandy paper increased the germination rate of Atlas cypress by up to 67%, indicating that the species possess essentially an exogenous dormancy （physical dormancy） due to the hard seed coat （hardseededness）. Exogenous application of gibberellic acid （GA3） at 1,000 mg.L-1 was also effective in breaking seed dormancy and germination induction. These two treatments induced faster speed germination expressed by low number of days to first germination （8-10 days） and low values of mean germination times （MGT）. However, germination rate, under any treatment, is greatly dependent on the year of seed collection. Seeds collected in year 2004 gave the highest value, suggesting that even after five years of storage, the germination capacity of C. atlantica seeds could remain high. This observation is very interesting in the ex-situ conservation of such endemic and endangered species where the production of seeds is irregular over the years.

关键词： Cupressus atlantica endemic endangered breaking seed dormancy germination capacity hand scarification ex-situ conservation

Mutations of the aurora kinase C gene causing macrozoospermia are the most frequent genetic cause of male infertility in Algerian men

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Asian Journal of Andrology 2015年第1期17卷 68-73,I0008页

作者： Leyla Ounis Abdelali Zoghmar Charles Coutton Leila Rouabah Maroua Hachemil delphine Martinez Guillaume Martinez Ines Bellil Douadi Khelifi Christophe Arnoult Julien Faure Sebti Benbouhedja Abdelkader Rouabah Pierre F Ray laboratoire de Biologie Moleculaire et Cellulaire Faculte des Sciences de la Nature et de la Vie Universite Constantine I Algerie Clinique Ibn Rochd Centre de Medecine de la Reproduction Constantine Algerie Universite Grenoble Alpes Grenoble France equipe Genetique Epigenetique et Therapies de I'lnfertilitE CNRS AGIM Grenoble France laboratoire de GEnetique Chromosomique CHU Grenoble Grenoble France laboratoire de Biochimie et Genetique Moleculaire CHU Grenoble Grenoble France equipe Muscle et Pathologies INSERM U836 Grenoble Institut des Neurosciences Grenoble France.

Klinefelter syndrome and Y-chromosomal microdeletion analyses were once the only two genetic tests offered to infertile men. Analyses of aurora kinase C （AURKCj and DPY19L2 are now recommended for patients presenting macrozoospermia and globozoospermia, respectively, two rare forms of teratozoospermia particularly frequent among North African men. We carried out genetic analyses on Algerian patients, to evaluate the prevalence of these syndromes in this population and to compare it with the expected frequency of Klinefelter syndrome and Y-microdeletions. We carried out a retrospective study on 599 consecutive patients consulting for couple infertility at the assisted reproduction unit of the Ibn Rochd Clinique, Constantine, Algeria. Abnormal sperm parameters were observed in 404 men. Fourteen and seven men had typical macrozoospermia and globozoospermia profiles, respectively. Molecular diagnosis was carried out for these patients, for the AURKC and DPY19L2 genes. Eleven men with macrozoospermia had a homozygous AURKC mutation （79%）, corresponding to 2.7% of all patients with abnormal spermograms. All the men with globozoospermia studied （n = 5）, corresponding to 1.2% of all infertile men, presented a homozygous DPY19L2deletion. By comparison, we would expect 1.6% of the patients in this cohort to have Klinefelter syndrome and 0.23% to have Y-microdeletion. Our findings thus indicate that AURKCmutations are more frequent than Klinefelter syndrome and constitute the leading genetic cause of infertility in North African men. Furthermore, we estimate that AURKCand DPY19L2 molecular defects are 10 and 5 times more frequent, respectively, than Y-microdeletions.

关键词： aurora kinase C DPY19L2 globozoospermia intracytoplasmic sperm injection infertility macrozoospermia