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A study of the effect of local scour on the flow field near the spur dike

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 98-105页

作者： Yu-Tian Li Jie-Min Zhan Wing-Hong Onyx Wai department of Industrial design School of Industrial Design and Ceramic ArtFoshan UniversityFoshan 528000China department of Applied Mechanics and Engineering Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

The flow field near a spur dike such as down flow and horseshoe vortex system(HVS)are susceptible to the topographic changes in the local scouring process,resulting in variation of the sediment transport with *** this study,large eddy simulations with fixed-bed at different scouring stages were conducted to investigate the changes in flow *** results imply that the bed deformation leads to an increase in flow rate per unit area,which represent the capability of sediment transportation by water,in the scour ***,the intensity of turbulent kinetic energy and bimodal motion near the sand bed induced by the HVS were also ***,the peak moments between the two sediment transport mechanisms were ***,understanding the complex feedback mechanism between topography and flow field is essential for the local scour problem.

关键词： Spur dike Local scour Large eddy simulation Down flow Horseshoe vortex system

Thermal noise-driven resonant sensors

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Microsystems & Nanoengineering 2024年第3期10卷 259-271页

作者： Yan Qiao Alaaeldin Elhady Mohamed Arabi Eihab Abdel-Rahman Wenming Zhang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghaiChina department of Systems design Engineering University of WaterlooWaterlooONCanada

MEMS/NEMS resonant sensors hold promise for minute mass and force ***,one major challenge is that conventional externally driven sensors inevitably encounter undesired intrinsic noise,which imposes a fundamental limitation upon their signal-to-noise ratio(SNR)and,consequently,the ***,this restriction becomes increasingly pronounced as sensors shrink to the *** this work,we propose a counterintuitive paradigm shift that turns intrinsic thermal noise from an impediment to a constituent of the sensor by harvesting it as the driving force,obviating the need for external actuation and realizing‘noise-driven’*** sensors employ the dynamically amplified response to thermal noise at resonances for stimulus *** demonstrate that lightly damped and highly compliant nano-structures with high aspect ratios are promising candidates for this class of *** overcome the phase incoherence of the drive force,three noise-enabled quantitative sensing mechanisms are *** validated our sensor paradigm by experimental demonstrating noise-driven pressure and temperature ***-driven sensors offer a new opportunity for delivering practical NEMS sensors that can function at room temperature and under ambient pressure,and a development that suggests a path to cheaper,simpler,and low-power-consumption sensors.

关键词： noise resonant overcome

DEM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

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Particuology 2024年第2期85卷 198-212页

作者： Minyi Zhu Guobin Gong Jun Xia Stephen Wilkinson department of Civil Engineering Xi'an Jiaotong-Liverpool UniversityChina department of Civil Engineering and Industrial design University of LiverpoolLiverpoolUK Faculty of Engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DEM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state Failure criterion

The dual role of striatal interneurons: circuit modulation and trophic support for the basal ganglia

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Neural Regeneration Research 2024年第6期19卷 1277-1283页

作者： Elliot Wegman Marlena Wosiski-Kuhn Yu Luo department of Molecular and Cellular Biosciences University of Cincinnati 2. Department of Emergency Medicine at the School of Medicine University of Cincinnati Neuroscience Graduate program University of Cincinnati

Striatal interneurons play a key role in modulating striatal-dependent behaviors, including motor activity and reward and emotional processing. Interneurons not only provide modulation to the basal ganglia circuitry under homeostasis but are also involved in changes to plasticity and adaptation during disease conditions such as Parkinson’s or Huntington’s disease. This review aims to summarize recent findings regarding the role of striatal cholinergic and GABAergic interneurons in providing circuit modulation to the basal ganglia in both homeostatic and disease conditions. In addition to direct circuit modulation, striatal interneurons have also been shown to provide trophic support to maintain neuron populations in adulthood. We discuss this interesting and novel role of striatal interneurons, with a focus on the maintenance of adult dopaminergic neurons from interneuronderived sonic-hedgehog.

关键词： cholinergic dopamine GABAergic interneuron levodopa-induced dyskinesia parvalbumin sonic hedgehog striatum trophic factor

Integrated photonic fractional convolution accelerator

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Photonics Research 2024年第8期12卷 1828-1839页

作者： KEVIN ZELAYA MOHAMMED-ALI MIRI department of Physics Queens College of the City University of New York Physics program The Graduate Center of the City University of New York

An integrated photonic circuit architecture to perform a modified-convolution operation based on the discrete fractional Fourier transform(DFrFT) is introduced. This is accomplished by utilizing two nonuniformly coupled waveguide lattices with equally spaced eigenmode spectra, the lengths of which are chosen so that the DFrFT and its inverse operations are achieved. A programmable modulator array is interlaced so that the required fractional convolution operation is performed. Numerical simulations demonstrate that the proposed architecture can effectively perform smoothing and edge detection tasks even for noisy input signals, which is further verified by electromagnetic wave simulations. Notably, mild lattice defects do not jeopardize the architecture performance, showing its resilience to manufacturing errors. ? 2024 Chinese Laser Press

关键词： Array waveguide devices Edge detection Fourier transforms Free space optics Numerical simulation Optical elements

Resilience conferred by APOE-R136S:a defense bestowed by nature to combat Alzheimer’s disease

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Signal Transduction and Targeted Therapy 2024年第3期9卷 831-832页

作者： Bin Xiao Joshua Kuruvilla Eng-King Tan department of Neurology National Neuroscience InstituteSingaporeSingapore Neuroscience Academic Clinical program Duke-NUS Medical SchoolSingaporeSingapore Neuroscience and Behavioural Disorders program Duke-NUS Medical SchoolSingaporeSingapore

In two recent articles published in Nature Neuroscience and Cell,Nelson et al.1 and Chen et al.2 have shown that a rare APOE3 Christchurch(APOE3Ch)variant,R136S,has protective effects on neurodegeneration in various Alzheimer’s disease(AD)model systems through attenuating tau pathology and regulating its related neuroimmune *** et *** Chen et *** provided evidence that identifying the pathophysiologic clues and potential molecular targets from a protective variant such as APOE R136S,can be an attractive viable approach to develop AD therapeutics.

关键词： protective al. Alzheimer

Assessing the energy saving potential of using adaptive setpoint temperatures:The case study of a regional adaptive comfort model for Brazil in both the present and the future

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Building Simulation 2024年第3期17卷 459-482页

作者： Daniel Sánchez-García David Bienvenido-Huertas Carlos Rubio-Bellido Ricardo Forgiarini Rupp department of Electrical Engineering University Carlos III of MadridMadridSpain department of Building Simulation ZEROCEM SLSevilleSpain department of Building Constructions University of GranadaGranadaSpain department of Building Constructions II University of SevilleSevilleSpain Section of design for Sustainability Department of Civil and Mechanical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

It has been found in recent years that using setpoint temperatures based on adaptive thermal comfort models is a successful method of energy *** studies using adaptive setpoint temperatures incorporate international models from ASHRAE Standard 55 and *** study,however,has instead considered a regional Brazilian adaptive comfort *** study investigates the energy demand arising from the use of a local Brazilian comfort model in order to assess the energy implications from the use of the worldwide ASHRAE Standard 55 adaptive model and various fixed setpoint *** of Brazil’s climate zones,full air-conditioning,mixed-mode building operating modes,present-day climate change scenarios,and future scenarios—specifically Representative Concentration Pathways(RCP)2.6,4.5,and 8.5 for the years 2050 and 2100—have all been taken into account in building energy *** use of adaptive setpoint temperatures based on the Brazilian local model considering mixed-mode has been found to significantly reduce energy consumption when compared to static setpoint temperatures(average energy-saving values ranging from 52%to 58%)and the ASHRAE 55 adaptive model(average values ranging from 15%to 21%).Considering climate change and the mixed-mode Brazilian model,the overall energy demand for the three groups of climatic zones(annual average outdoor temperatures≤21℃,>21 and≤25℃and>25℃)ranged between 2%decrease and 5%increase,4%and 27%increase,and 13%and 45%increase,*** is concluded as a consequence that setting setpoint temperatures based on the Brazilian local adaptive comfort model is a very efficient energy-saving method.

关键词： adaptive thermal comfort building energy simulation energy efficiency climate change adaptive setpoint temperatures local comfort mode

Perspectives for delivery of therapeutics by extravasation of biodegradable microspheres in the brain

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Neural Regeneration Research 2024年第5期19卷 969-970页

作者： Anne-Eva van der Wijk Ed VanBavel Amsterdam UMC location University of Amsterdam Department of Biomedical Engineering and PhysicsAmsterdamThe Netherlands Amsterdam Neuroscience Neurovascular Disorders ProgramAmsterdamThe Netherlands Amsterdam Cardiovascular Sciences Microcirculation ProgramAmsterdamThe Netherlands

Development of therapeutics for brain diseases has remained challenging,in particular due to the difficulty of passing the blood-brain *** a result,the current arsenal of therapeutics targeting the brain is limited to small,lipid-soluble drugs and there is a lack of options for treating neuroblastomas,Alzheimer’s disease,and many other devastating *** the advances in strategies for crossing the blood-brain barrier such as the use of nanoparticles(Hersh et al.,2022;Duan et al.,2023),such delivery systems have not yet reached clinical ***,novel platforms for the transport of therapeutics across the blood-brain barrier remain highly *** specifically holds for large molecules such as monoclonal antibodies and recombinant proteins,as well as nucleotide-based therapeutics and cell *** efforts in this field are increasing exponentially,with thousands of publications in the last few years.

关键词： therapeutics holds spite

A sphingolipid message promotes neuronal health across generations

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Neural Regeneration Research 2024年第11期19卷 2325-2326页

作者： Wenyue Wang Roger Pocock Development and Stem Cells program Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental BiologyMonash UniversityMelbourneVICAustralia

Maternal nutrition can affect brain function of offspring in later life(Fitzgerald et al.,2020).Emerging studies have also shown that the maternal environment can modify susceptibility to neurodegenerative disease(Boots et al.,2023).Transmission of environmental information from mother to offspring depends on maternal nutrient *** the nematode Caenorhabditis elegans,maternal yolk,which is synthesized in the intestine and transferred to nourish oocytes and early embryos,can provide extranuclear inheritance factors to mediate phenotypic plasticity across ***,the molecular mechanisms of regulating such intergenerational effects remain largely unknown.

关键词： mother intestine transferred