During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or ...
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During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red
We investigate the flow inside a 2D square cavity driven by the motion of two mutually facing walls independently sliding at different *** exploration,which employs the lattice Boltzmann method(LBm),extends on previou...
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We investigate the flow inside a 2D square cavity driven by the motion of two mutually facing walls independently sliding at different *** exploration,which employs the lattice Boltzmann method(LBm),extends on previous studies that had the two lids moving with the exact same speed in opposite *** there,here the flow is governed by two Reynolds numbers(Re_(T),Re_(B))associated to the velocities of the two moving *** convenience,we define a bulk Reynolds number Re and quantify the driving velocity asymmetry by a parameterα.Parameterαhas been defined in the rangeα∈[-π4,0]and a systematic sweep in Reynolds numbers has been undertaken to unfold the transitional dynamics path of the two-sided wall-driven cavity *** particular,the critical Reynolds numbers for Hopf and NeimarkSacker bifurcations have been determined as a function ofα.The eventual advent of chaotic dynamics and the symmetry properties of the intervening solutions are also analyzed and *** study unfolds for the first time the full bifurcation scenario as a function of the two Reynolds numbers,and reveals the different flow topologies found along the transitional path.
The nanocrystalline samples Nd_(1-x)m_(x)FeO_(3)(x=0.0 and 0.1;m:Co^(2+)and Ni^(2+))were prepared using the citrate combustion *** X-ray diffraction(XRD)pattern confirmed that the nanoparticles were synthesized in an ...
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The nanocrystalline samples Nd_(1-x)m_(x)FeO_(3)(x=0.0 and 0.1;m:Co^(2+)and Ni^(2+))were prepared using the citrate combustion *** X-ray diffraction(XRD)pattern confirmed that the nanoparticles were synthesized in an orthorhombic *** particle size of Nd_(1-x)m_(x)FeO_(3) is in the range of 29-59 *** selected area electron diffraction(SAED)indicates the samples were prepared in a polycrystalline *** samples Nd_(1-x)m_(x)FeO_(3)(x=0.0 and 0.1;m:Co^(2+)and Ni^(2+))have anti ferromagnetic *** Fe^(3+)spins are aligned antiparallel,forming the antiferromagnetic(AFm)properties,which are affected by many factors such as the bond angle between the Fe^(3+)(Fe^(3+)-O_(2)--Fe^(3+))and the Dzyaloshinskii-moriya(D-m)*** doping of Co^(2+)and Ni^(2+)ions in NdFeO_(3) enhances the magnetic properties of the NdFeO_(3).The saturation magnetization(ms)of Nd_(0.90)Co_(0.10)FeO_(3) increases 1.8times more than that of NdFeO_(3).The exchange bias field(HEX)of the Co-doped sample is two times greater than that of NdFeO_(3).The magnetic anisotropy constant(K)of the 10%Co-doped sample increases by 11 factors compared to that of NdFeO_(3).The Tauc plot illustrates that the samples have a direct optical *** divalent cation substitution(Co^(2+)and Ni^(2+))decreases the optical band gap of NdFeO_(3),leading to the recommendation of using the samples Nd_(0.90)Co_(0.10)FeO_(3) and Nd_(0.90)Ni_(0.10)FeO_(3) in photocatalysis of dye degradation from *** removal efficiencies of Cr6+at pH=6 are 88.06%,85.54%,and 85.52%for the samples NdFeO_(3),Nd_(0.90)Co_(0.10)FeO_(3),and Nd_(0.90)Ni_(0.10)FeO_(3),*** Freundlich isotherm mode is the best-fit model for NdFeO_(3) to adsorb Cr6+ions from aqueous solutions.
This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and sub...
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This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.
Inspired by nature's self-similar designs,novel honeycomb-spiderweb based self-similar hybrid cellular structures are proposed here for efficient energy absorption in impact *** energy absorption is enhanced by optimi...
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Inspired by nature's self-similar designs,novel honeycomb-spiderweb based self-similar hybrid cellular structures are proposed here for efficient energy absorption in impact *** energy absorption is enhanced by optimizing the geometry and topology for a given *** proposed hybrid cellular structure is arrived after a thorough analysis of topologically enhanced self-similar *** optimized cell designs are rigorously tested considering dynamic loads involving crush and high-velocity bullet ***,the influence of thickness,radial connectivity,and order of patterning at the unit cell level are also *** maximum crushing efficiency attained is found to be more than 95%,which is significantly higher than most existing traditional *** on,the first and second-order hierarchical self-similar unit cell designs developed during crush analysis are used to prepare the cores for sandwich *** tests are performed on the developed sandwich structures using the standard 9-mm *** influence of multistaging on impact resistance is also investigated by maintaining a constant total thickness and mass of the sandwich ***,in order to avoid layer-wise weak zones and hence,attain a uniform out-of-plane impact strength,off-setting the designs in each stage is *** sandwich structures with first and second-order self-similar hybrid cores are observed to withstand impact velocities as high as 170 m/s and 270 m/s,respectively.
Causality,the science of cause and effect,has made it possible to create a new family of *** models are often referred to as causal *** those of mathematical,numerical,empirical,or machine learning(mL)nature,causal mo...
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Causality,the science of cause and effect,has made it possible to create a new family of *** models are often referred to as causal *** those of mathematical,numerical,empirical,or machine learning(mL)nature,causal models hope to tie the cause(s)to the effect(s)pertaining to a phenomenon(i.e.,data generating process)through causal *** paper presents one of the first works at creating causal models in the area of structural and construction *** this end,this paper starts with a brief review of the principles of causality and then adopts four causal discovery algorithms,namely,PC(Peter-Clark),FCI(fast causal inference),GES(greedy equivalence search),and GRa SP(greedy relaxation of the sparsest permutation),have been used to examine four phenomena,including predicting the load-bearing capacity of axially loaded members,fire resistance of structural members,shear strength of beams,and resistance of walls against impulsive(blast)*** from this study reveal the possibility and merit of discovering complete and partial causal ***,this study also proposes two simple metrics that can help assess the performance of causal discovery algorithms.
This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic...
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This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.
This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velo...
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This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(mHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in mATHEmATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.
On January 7,2025,01:05:15 UTC (9:05 *** time) southern Tibet was rocked by a mw7.1 earthquake (mw=moment magnitude,USGS) centered(28.639°N 87.361°E) in the Lhasa Block north of the India/Eurasia Plate boundar...
On January 7,2025,01:05:15 UTC (9:05 *** time) southern Tibet was rocked by a mw7.1 earthquake (mw=moment magnitude,USGS) centered(28.639°N 87.361°E) in the Lhasa Block north of the India/Eurasia Plate boundary,in a remote area about 180km SW of Xigaze,in Dingri County of Shigatse of the Xizang Autonomous Region (Figure 1).The China Earthquake Networks Center measured the magnitude differently,using surface wave magnitude,ms,at *** of Jan.10,a total of 126 people were confirmed dead,another 188 injured,and about 61 500 people displaced from their *** region is currently being shaken by thousands of aftershocks,which are likely to continue for weeks or *** than 14 000 search and rescue personnel have been deployed to the epicentral region.
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 inh...
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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
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