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Computers, materials & Continua 2022年第8期72卷 3751-3762页

作者： Ahmed.A.Rosas mona Shokair m.i.dessouky Department of Electronics and Electrical Communication Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

With the obvious throughput shortage in traditional cellular radio networks,Device-to-Device(D2D)communications has gained a lot of attention to improve the utilization,capacity and channel performance of nextgeneration *** this paper,we study a joint consideration of power and channel allocation based on genetic algorithm as a promising direction to expand the overall network capacity for D2D underlaied cellular *** genetic based algorithm targets allocating more suitable channels to D2D users and finding the optimal transmit powers for all D2D links and cellular users efficiently,aiming to maximize the overall system throughput of D2D underlaied cellular network with minimum interference level,while satisfying the required quality of service QoS of each *** simulation results show that our proposed approach has an advantage in terms of maximizing the overall system utilization than fixed,random,BAT algorithm(BA)and Particle Swarm Optimization(PSO)based power allocation schemes.

关键词： 5G D2D communication spectrum allocation power allocation genetic algorithm optimization BAT-optimization particle swarm optimization

Reservation-based dynamic admission control scheme for wideband code division multiple access systems

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Journal of Central South University 2012年第2期19卷 393-401页

作者： A.Y.Al-nahari S.A.El-Dolil m.i.dessouky F.E.Abd El-Samie Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia University

Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very scarce resource as the radio spectrum. A new scheme was proposed which extends the concepts of resource sharing and reservations for wideband code division multiple access (WCDmA) systems with a unique feature of soft capacity. Voice and data traffic were considered. The traffic is further classified into handoff and new requests. The reservation thresholds were dynamically adjusted according to the traffic pattern and mobility prediction in order to achieve the maximum channel utilization, while guaranteeing different QoS constraints. The performance of proposed scheme was evaluated using markov models. New call blocking probability, handoff call dropping probability, and channel utilization were used as benchmarks for the proposed scheme.

关键词： admission control resource reservation wideband code division multiple access resource utilization

Peak-to-average power ratio reduction using selective mapping with unequal power distribution

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Journal of Central South University 2012年第7期19卷 1902-1908页

作者： E.S.Hassan XU Zhu S.E.E1-Khamy m.i.dessouky S.A.Ei-Dolill F.E.Abd Ei-Samie Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Electrical Engineering and Electronics The University of LiverpoolLiverpool L693G JUK Department of Electrical Engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt

A new approach for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDm) systems was *** approach is based on assigning powers to the different subcarriers of OFDm using an unequal power distribution *** addition,a reduced complexity selective mapping (RC-SLm) scheme was *** proposed scheme is based on partitioning the frequency domain symbol sequence into several sub-blocks,and then each sub-block is multiplied by different phase sequences whose length is shorter than that used in the conventional SLm ***,a kind of low complexity conversions is used to replace the iFFT *** performance of the proposed RC-SLm scheme along with the new approach was studied with computer *** obtained results show that the proposed RC-SLm scheme is able to achieve the lowest computational complexity when compared with other low complexity schemes proposed in the literature while at the same time improves the PAPR reduction performance by about 0.3 dB.

关键词： orthogonal frequency division multiplexing (OFDm) peak-to-average power ratio (PAPR) computational complexity selective mapping scheme

Ra's Abdah of the north Eastern Desert of Egypt:the role of granitic dykes in the formation of radioactive mineralization,evidenced by zircon morphology and chemistry

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Acta Geochimica 2016年第4期35卷 368-380页

作者： Ali A.Omran Osama K.dessouky Nuclear materials Authority P.O.Box 530El MaadiCairoEgypt

Syenogranitic dykes in the north of Egypt's Eastern Desert are of geological and economic interest because of the presence of magmatic and supergene enrichment of radioactive mineralization. Zircon crystal morphology within the syenogranitic dykes allows precise definition of sub-alkaline series granites and crystallized at mean temperature of about 637 °C. The growth pattern of the zircons suggest magmatic and hydrothermal origins of radioactive mineralization. Hydrothermal processes are responsible for the formation of significant zircon overgrowth; high U-zircon margins might have occurred contemporaneously with the emplacement of syenogranitic dykes which show anomalous uranium(e U) and thorium(e Th) contents of up to 1386 and 7330 ppm, *** chemistry revealed a relative increase of Hf consistent with decreasing Zr content, suggesting the replacement of Zr by Hf during hydrothermal *** uranium mineralization is present and recognized by the presence of uranophane and autunite.

关键词： Syenogranitic dykes Zircon morphology Typology Uranium Egypt

Using Portable Gamma-Ray Spectrometry for Testing Uranium migration: A Case Study from the Wadi El Kareim Alkaline Volcanics,Central Eastern Desert, Egypt

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2214-2232页

作者： Osama K. dessouky Hani H. ALi Nuclear materials Authority P.O.Box 530El MaadiCairoEgypt

The 300±20 ma anomalously radioactive trachytes of Wadi El Kareim, central Eastern Desert, are a significant example of U-mineralization related to the alkaline volcanics in Egypt. Extensive portable gamma-ray spectrometric data has been utilized to identify geological factors controlling uranium mobility in the geological units along the three detailed study locations of Kab Al-Abyad, South Wadi(W) Al-Tarafawy and W. Al-Farkhah; their eT h/eU ratios averaging around 4.1, 3.7 and 5.6 respectively. Quantitative analysis with the integration of mobility maps and geological studies suggest two systems controlling U-migration within the geological units(confined system and unconfined system). in the confined system, the syngenetically formed U have experienced mobility after leaching and are redistributed in the presence of an incorporation carrier during transportation(probably as carbonate complexes). Then the retardant for uranium is achieved by sorption or by coprecipitation with the aid of Fe oxy-hydroxide, and finally the formation of immobile secondary U-bearing minerals takes place along a lithogeochemical trap. in contrast to the confined system, the unconfined one is basically lacking the lithogeochemical trap which influences the final accumulation of U-bearing minerals. The radioactivity of the trachyte rocks arises from the radioactive minerals uranophane and betauranophane with U-and/or Th-bearing minerals samarskite, Th-rich REE silicates, monazite and allanite.

关键词： radioactivity uranium migration systems alkaline volcanics Egypt

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza i.Torrado-Tapias iris K.Salgado Jose m.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA institute of Neurobiology San JuanPRUSA

in addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Gauss Gradient and SURF Features for Landmine Detection from GPR images

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Computers, materials & Continua 2022年第6期71卷 4457-4486页

作者： Fatma m.El-Ghamry Walid El-Shafai mahmouad i.Abdalla Ghada m.El-Banby Abeer D.Algarni moawad i.dessouky Adel S.Elfishawy Fathi E.Abd El-Samie Naglaa F.Soliman Department of Electronics and Communications Engineering Faculty of EngineeringZagazig UniversityZagazigSharqia44519Egypt Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenoufia32952Egypt Department of industrial Electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

Recently,ground-penetrating radar(GPR)has been extended as a well-known area to investigate the subsurface ***,its output has a low resolution,and it needs more processing for more *** paper presents two algorithms for landmine detection from GPR *** first algorithm depends on a multi-scale technique.A Gaussian kernel with a particular scale is convolved with the image,and after that,two gradients are estimated;horizontal and vertical ***,histogram and cumulative histogram are estimated for the overall gradient *** bin values on the cumulative histogram are used for discrimination between images with and without ***,a neural classifier is used to classify images with cumulative histograms as feature *** second algorithm is based on scale-space analysis with the number of speeded-up robust feature(SURF)points as the key parameter for *** addition,this paper presents a framework for size reduction of GPR images based on decimation for efficient *** further classification steps can be performed on images after *** sensitivity of classification accuracy to the interpolation process is studied in detail.

关键词： GPR images cumulative histogram gradient image neural classifier SURF

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

mitochondria–cGAS–STiNG axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.izquierdo Centro de Biología molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

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Neural Regeneration Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Radiology University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Foundation Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging *** and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory *** mechanisms which underpin the integration of these multisensory signals are the principal topic of the present *** multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older *** emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

关键词： aging balance encephalography functional magnetic resonance imaging gait multisensory integration Parkinson’s disease positron emission tomography somatosensory vestibular visual