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Optical nonlinearities of tetracarbonyl-chromium triphenyl phosphine complex

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Chinese Physics B 2017年第4期26卷 214-218页

作者： m d zidan A W Allaf A Allahham A AL-Zier department of Physics Atomic Energy CommissionP.O.Box 6091DamascusSyria department of Chemistry Atomic Energy CommissionP.O.Box 6091DamascusSyria

The new tetracarbonyl - chromium-triphenyl phosphine complex was synthesized and characterized using ultraviolet（UV）-visible,Fourier transform infrared（FTIR）,and nuclear magnetic resonance（NmR） *** characterization results confirm the molecular structure of the new *** z-scan measurements were done by diode laser[continuous wave（CW）]to estimate the nonlinear optical parameter（X^3）.The results led to calculate three parameters：the groundstate cross sections（σ_g）,the excited-state cross sections（σ_（ex））,and thermo-optic coefficient of the new *** study indicated that our complex is a suitable for photonic applications.

关键词： tetra carbonyl-chromium triphenyl phosphine Z-scan technique nonlinear optical materials

Numerical simulation for symmetric diffraction patterns of 8-hydroxyquinolin-1-ium 4-aminobenzenesulfonate

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Optoelectronics Letters 2022年第5期18卷 283-287页

作者： A.Ghanem m.d.zidan m.S.EL-daher A.Allahham Higher Institute for Laser Research and Applications Damascus UniversiySyria department of Physics AECP.O.Box 6091DamascusSyria

We reported the formation of diffraction ring patterns induced by transmitted Gaussian laser beam through 8-hydroxyquinolin-1-ium 4-aminobenzenesulfonate(8 HQABS) solution as absorbing medium. Theoretical model depending on the Fresnel-Kirchhoff diffraction(FKd) theory was used to generate diffraction rings with respect to the sample position. Analysis of the generated diffraction rings shows a reasonable agreement between the features of the experimental and numerical diffraction rings. Our results are considered to be useful to understand the way of propagation and interaction of laser beam with liquid absorbing medium.

关键词： benzene rings absorbing

Thermal lens study of the Tris(2,2’-bipyridyl)iron(Ⅱ) tetrafluoroborate

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Optoelectronics Letters 2021年第3期17卷 183-186页

作者： m.d.zidan m.m.Al-Ktaifani m.S.EL-daher A.Allahham A.Ghanem department of Physics Atomic Energy CommissionDamascus P.O.Box 6091Syria department of Radioisotopes Atomic Energy CommissionDamascus P.O.Box 6091Syria Higher Institute for Laser Research and Applications Damascus UniversitySyria

Experimental results of thermal lens measurements for Tris(2,2’-bipyridyl)iron(II) tetrafluoroborate solution are reported using the dual beam technique. The temporal evaluation of thermal lens was observed at input pump power of I=47 mW. The thermal lens effect was observed with increasing the pump power intensity as well. The evolution time of thermal lens and the fitting of the experimental transient curve were useful to evaluate the parameters of the Tris(2,2’-bipyridyl)iron(Ⅱ) tetrafluoroborate solution.

关键词： technique. solution. (Ⅱ)

Neuromorphic computing with memristive devices

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Science China(Information Sciences) 2018年第6期61卷 136-144页

作者： Wen mA mohammed A.zidan Wei d.LU department of Electrical Engineering and Computer Science University of Michigan

Technology advances in the last a few decades have resulted in profound changes in our society, from workplaces to living rooms to how we socialize with each other. These changes in turn drive further technology developments, as the exponential growth of data demands ever increasing computing power. However, improvements in computing capacity from device scaling alone is no longer sufficient, and new materials, devices, and architectures likely need to be developed collaboratively to meet present and future computing needs. Specifically, devices that offer co-located memory and computing characteristics,as represented by memristor devices and memristor-based computing systems, have attracted broad interest in the last decade. Besides tremendous appeal in data storage applications, memristors offer the potential for efficient hardware realization of neuromorphic computing architectures that can effectively address the memory and energy walls faced by conventional von Neumann computing architectures. In this review, we evaluate the state-of-the-art in memristor devices and systems, and highlight the potential and challenges of applying such devices and architectures in neuromorphic computing applications. New directions that can lead to general, efficient in-memory computing systems will also be discussed.

关键词： memristor resistive random-access-memory(RRAm) neuromorphic computing non-von Neumann process in-memory

Spin excitations in nickelate superconductors

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Science China(Physics,mechanics & Astronomy) 2020年第8期63卷 114-122页

作者： Tao Zhou Yi Gao zidan Wang Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum materials Guangdong Provincial Engineering Technology Research Center for Quantum Precision MeasurementSchool of Physics and Telecommunication Engineeringand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China department of Physics and HKU-UCAS Joint Institute for Theoretical and Computational Physics at Hong Kong The University of Hong KongHong Kong 999077China

Applying a three-band model and the random phase approximation,we theoretically study the spin excitations in nickelate superconductors,which have been newly *** spin excitations were found to be incommensurate in the low energy *** spin resonance phenomenon emerged as the excitation energy *** intensity can be maximized at the incommensurate or commensurate momentum,depending on the out-of-plane *** spin excitations reverted to incommensurate at higher *** also discuss the similarities and differences in the spin excitations of nickelate and cuprate *** predicted results can be later validated in inelastic neutron scattering experiments.

关键词： nickelates superconductivity d-wave pairing spin susceptibility

Advances in aptamer-based nanomaterials for separation and analysis of non-genetic biomarkers in biofluids

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Science China Chemistry 2021年第6期64卷 932-947页

作者： zidan Wang Chuwen Huang Nianrong Sun Chunhui deng department of Gastroenterology Zhongshan Hospital of Fudan UniversityShanghai 200032China department of Chemistry Fudan UniversityShanghai 200032China

Body fluids contain a large number of disease markers including proteins,exosomes and cells,the concentration of which indicates the health status of a body system and can be hence applied to predict the degree of seriousness of a ***,the content of disease markers is relatively *** solving this problem,a variety of pretreatment methods have been developed,among which aptamer-based nanomaterials hold great potential for biomarker capture because of various natural properties of nano-substrates such as high specific surface area,as well as the high affinity of aptamer towards target and the higher stability than *** this review,we summarized the recent aptamer-based nanomaterials for the separation and analysis of different biomarkers including proteins,exosomes and *** specifically,the standard of classification description was based on the applied substrates including magnetic substrates and non-magnetic ***,the perspective of aptamer-based nanomaterials was discussed.

关键词： aptamers nanomaterials proteins cells exosomes biomarkers

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa department of Psychology and Neuroscience Duke UniversityDurhamNCUSA department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 574-586页

作者： Olivier Kerdiles méryl-Farelle Oye mintsa mi-mba Katherine Coulombe Cyntia Tremblay VincentÉmond martine Saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon Facultéde pharmacie UniversitéLaval1050 Avenue de la MédecineQuebecQCCanada Axe Neuroscience Centre de recherche du CHU de Québec-UniversitéLaval(Pavillon CHUL)2705 Boulevard LaurierQuebecQCCanada Institute of Nutrition and Functional Foods QuebecQCCanada Optinutribrain International Associated Laboratory(NutriNeuro FranceINAFCanada)QuebecQCCanada Axe Endocrinologie et Néphrologie Centre de recherche du CHU de Québec-UniversitéLavalQuebecQCCanada département de médecine Facultéde MédecineUniversitéLavalQuebecQCCanada département de Psychiatrie et Neurosciences Facultéde MédecineQuebecQCCanada

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after *** that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic ***,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal *** weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 *** this period,the animals had access to a running wheel,which they could use or *** acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars ***,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned *** to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal dOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned *** present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

关键词： 6-hydroxydopamine dopamine dopamine transporter exercise neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3

Amino Acid Encryption method Using Genetic Algorithm for Key Generation

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Computers, materials & Continua 2022年第1期70卷 123-134页

作者： Ahmed S.Sakr m.Y.Shams Amena mahmoud mohammed zidan department of Information System Faculty of Computers and InformationMenofia UniversityEgypt department of machine learning and Information Retrieval Faculty of Artificial IntelligenceKafrelsheikh UniversityEgypt department of Computer Science Faculty of Computers and InformationKafrelshiekh UniversityEgypt Hurghada Faculty of Computers and Artificial Intelligence South Valley UniversityEgypt

In this new information era,the transfer of data and information has become a very important *** data must be kept secured from unauthorized persons using *** science of cryptography depends not only on complex mathematical models but also on encryption *** acid encryption is a promising model for data *** this paper,we propose an amino acid encryption model with two encryption *** first key is generated randomly using the genetic *** second key is called the protein key which is generated from converting dNA to a protein ***,the protein message and the first key are used in the modified Playfair matrix to generate the cypher *** experimental results show that the proposed model survives against known attacks such as the Brute-force attack and the Ciphertext-only *** addition,the proposed model has been tested over different types of characters including white spaces and special characters,as all the data is encoded to 8-bit *** performance of the proposed model is compared with other models using encryption time and decryption *** model also balances all three principles in the CIA triad.

关键词： Cryptography amino acid genetic algorithm playfair deep learning dNA computing