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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 389-401页

作者： Adolfo Foriero Filippo Santucci de Magistris giovanni Fabbrocino Département de génie civil et de génie des eaux Pavillon Adrien-PouliotUniversitéLavalQuébecCanada Dipartimento di Bioscienze e Territorio Universitàdegli Studi del MoliseCampobassoItaly Construction Technologies Institute National Research CouncilITC-CNRL’AquilaItaly

This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact *** approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the *** development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are *** study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably *** particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification *** computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem.

关键词： beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor

Numerical Simulation of Turbulent Diffusion Flames of a Biogas Enriched with Hydrogen

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Fluid Dynamics & Materials Processing 2024年第1期20卷 79-96页

作者： Naima Krarraz Amina Sabeur Khadidja Safer Ahmed Ouadha Laboratoire des Science et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des Carburants gazeux et de l’Environnement Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic fermentation of organic materials has the advantage of being an environmentally friendly ***,the relatively low calorific value of such gases makes their effective utilization in practical applications relatively *** present study considers the addition of hydrogen as a potential solution to mitigate this *** particular,the properties of turbulent diffusion jet flames and the related pollutant emissions are investigated numerically for different operating *** related numerical simulations are conducted by solving the RANS equations in the frame of the Reynolds Stress Model in combination with the flamelet *** effects are also taken into account and the combustion kinetics are described via the gRI-Mech 3.0 reaction *** considered hydrogen fuel enrichment spans the range from 0%to 50%in terms of *** varies between 1 and 10 *** results show that both hydrogen addition and pressure increase lead to an improvement in terms of mixing quality and have a significant effect on flame temperature and *** also reduce CO_(2) emissions but increase NOx *** NO is shown to be the predominant NO formation mechanism.

关键词： Biogas hydrogen diffusion flame turbulence NO formation route pressure

Optimization of variables and assessment of in-vitro and in-vivo antihyperlipidemic activity of Eudragit RS nanoparticles containing simvastatin

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Particuology 2024年第7期90卷 189-198页

作者： Bina gidwani Vishal Jain Veenu Joshi Ravindra Kumar Pandey Shiv Shankar Shukla Amber Vyas Columbia Institute of Pharmacy Raipur(C.G.)India University Institute of Pharmacy Pt Ravishankar Shukla UniversityRaipur(C.G.)India Center for Basic Science and Research Pt Ravishankar Shukla UniversityRaipur(C.G.)India

Simvastatin, a BCS class II drug, is associated with poor aqueous solubility, first-pass metabolism and short half-life. In the present work, nanoparticles were prepared and evaluated. Optimization of formulation and process parameters was done through the use of independent and dependent variables. Preliminary studies were done to determine suitable range of the concentration of Eudragit polymer (10%–30%) and the ratio of drug to polymer (1:1 to 1:5) for the formation of nanoparticles by emulsification and a solvent evaporation technique. Results revealed that the mean size of nanoparticles was affected by stirring speed from 5000 RPM, 8000 RPM, and 12000 RPM. The results of increase in association efficiency and percent yield with increase in amount of drug from 100 mg, 150 mg, and 200 mg in selected range were observed. In-vitro release studies showed that two formulations possess highest initial burst and slow sustained drug release. There was 2.93-fold decrease in total cholesterol and 3.27-fold increases in triglyceride level during in-vivo study.

关键词： Simvastatin Eudragit RS 100 Nanoparticles Hyperlipidemia

Strain-dependent alpha-synuclein spreading in Parkinson's disease and multiple system atrophy

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Neural Regeneration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang Paul Lingor Department of Neurology School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany Department of Neurology University Medical Center GöttingenGöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(PD) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and Dementia with Lewy bodies,are neurodegenerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn aggregates propagate throughout the brain in a prion-like manner,where pathological a-syn recruits endogenous a-syn to form insoluble *** forms representing intermediates on the way to insoluble aggregates result in the most pronounced neurotoxic effects.

关键词： atrophy endogenous atypical

Ca^(2+) binding to the C_(2)E domain of otoferlin is required for hair cell exocytosis and hearing

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Protein & Cell 2024年第4期15卷 305-312页

作者： Han Chen Mehar Monga Qinghua Fang Loujin Slitin Jakob Neef Shashank S.Chepurwar Regina Célia Mingroni Netto Karina Lezirovitz Alfredo Tabith,Jr. Fritz Benseler Nils Brose Kathrin Kusch Carolin Wichmann Nicola Strenzke Barbara Vona Julia Preobraschenski Tobias Moser Institute for Auditory Neuroscience and InnerEarLab University Medical Center Göttingen37075 GöttingenGermany Collaborative Research Center 889 University of Göttingen37075 GöttingenGermany Auditory Neuroscience and Synaptic Nanophysiology group Max Planck Institute for Multidisciplinary Sciences37075 GöttingenGermany göttingen graduate Center for Neurosciences Biophysics and Molecular BiosciencesUniversity of Göttingen37075 GöttingenGermany Biochemistry of Membrane Dynamics group Institute for Auditory NeuroscienceUniversity Medical Center Göttingen37075 GöttingenGermany Molecular Architecture of Synapses group Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center Göttingen37075 GöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center Göttingen37075 GöttingenGermany Auditory Systems Physiology group Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center Göttingen37075 GöttingenGermany Departamento de genética e Biologia Evolutiva Centro de Pesquisas sobre o Genoma Humano e Células-TroncoInstituto de BiociênciasUniversidade de São PauloSão Paulo 05508-220Brazil Laboratório de Otorrinolaringologia/LIM32 Faculdade de MedicinaHospital das ClínicasUniversidade de São PauloSão PauloSP 05508-220Brazil DERDIC Pontifícia Universidade Católica de São PauloSão Paulo 05508-220Brazil Department of Molecular Neurobiology Max Planck Institute for Multidisciplinary Sciences37075 GöttingenGermany Multiscale Bioimaging Cluster of Excellence(MBExC) University of Göttingen37075 GöttingenGermany Functional Auditory genomics group Auditory Neuroscience and Optogenetics LaboratoryGerman Primate Center37077 GöttingenGermany Hearing genomics group Institute for Auditory Neuroscience and InnerEarLabUniversity Medical Center Göttingen37075 GöttingenGermany Institute of Human genetics University Medical Center Göttingen37075 GöttingenGermany

Dear Editor,Afferent synapses of cochlear inner hair cells(IHCs)employ a unique molecular machinery(see extended background in Supplementary Materials).Otoferlin is a key player in this machinery and its defects cause human auditory synaptopathy(Moser and Starr,2016).Otoferlin,a tail-anchored(Vogl et al.,2016)multi-C_(2)-domain protein(Fig.1Ai)specific to hair cells(Roux et al.,2006),is a member of the ferlin protein family involved in membrane trafficking and repair that are of major disease relevance(Pangršičet al.,2012),also see Supplementary *** is distributed broadly within IHCs(Fig.2Ai-Aiii;Pangrsic et al.,2010;Roux et al.,2006).

关键词： auditory hair

Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines

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Journal of Rock Mechanics and geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan Na Zhang Bei Jiang Wei Victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering

Understanding the Recovery of the Intervertebral Disc:A Comprehensive Review of In Vivo and In Vitro Studies

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Journal of Bionic Engineering 2024年第4期21卷 1919-1948页

作者： Faten Feki Fahmi Zaïri Abderrahman Tamoud Melissa Moulart Rym Taktak Nader Haddar Fahed Zaïri Sfax University ENISMaterials Engineering and Environment Laboratory3038SfaxTunisia University of Lille IMT Nord EuropeJUNIAUniversity of ArtoisULR 4515-LGCgELaboratoire de Génie Civil et geo-Environnement59000LilleFrance PrediTwins Lab 59000LilleFrance Japet Medical Device 59000LilleFrance Sfax University ENISLaboratory of Advanced Materials3038SfaxTunisia Ramsay générale de Santé Hôpital PrivéLe Bois59000LilleFrance

Within the consistent daily rhythm of human life,intervertebral discs endure a variety of complex loads beyond the influences of gravity and muscle forces,leading to significant morphological changes(in terms of volume,area,and height)as well as biomechanical alterations,including an increase in disc stiffness and a decrease in intradiscal ***,the discs demonstrate an ability to regain their original morphological and biomechanical characteristics after a period of nocturnal *** preservation of normal disc function is critically dependent on this recovery phase,which serves to forestall premature disc *** phenomenon of disc recovery has been extensively documented through numerous in vivo studies employing advanced clinical techniques such as Magnetic Resonance Imaging(MRI),stadiometry,and intradiscal pressure ***,the findings from in vitro studies present a more complex picture,with reports varying between full recovery and only partial recuperation of the disc ***,research focusing on degenerated discs in vitro has shed light on the quantifiable impact of degeneration on the disc ability to *** dynamics within the disc are considered a primary factor in recovery,yet the disc intricate multiscale structure and its viscoelastic properties also play key *** elements interact in complex ways to influence the recovery mechanism,particularly in relation to the overall health of the *** objective of this review is to collate,analyze,and critically evaluate the existing body of in vivo and in vitro research on this topic,providing a comprehensive understanding of disc recovery *** understanding offers a blueprint for future advancements in medical treatments and bionic engineering solutions designed to mimic,support,and enhance the natural recovery processes of intervertebral discs.

关键词： Intervertebral disc Recovery In vivo vs.in vitro studies Degeneration Viscoelastic effects Fluid dynamics

Model Predictive Current Control for Low-Cost Shunt Active Power Filter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1589-1598页

作者： Ali A.Abdel-Aziz Mohamed A.Elgenedy Barry W.Williams the Electronic and Electrical Engineering Department Strathclyde UniversityGlasgowG11XQUK School of Computing Engineering and the Built Environment(SCEBE)Glasgow Caledonian UniversityGlasgowG40BAUK

Performance of a three-phase shunt active power filter(SAPF)relies on the capability of the controller to track the reference ***,designing an accurate current controller is crucial to guarantee satisfactory SAPF *** paper presents a model predictive current controller(MPCC)for a low-cost,four-switch,shunt active power filter for power quality improvement.A four-switch,B4,converter topology is adopted as an SAPF,hence offering a simple,robust,and low-cost *** addition,to further reduce overall cost,only two interfacing filter inductors,instead of three,are used to eliminate switching current *** proposed SAPF model MPCC is detailed for implementation,where simulation and experimental results validate effectiveness of the proposed control algorithm showing a 20%improvement in total harmonic distortion compared with a conventional hysteresis band current controller.

关键词： Four-switch converter harmonic distortion model predictive current control power quality shunt active power filter

Photoelectrochemical Iron-Catalyzed C(sp^(3))-H Borylation of Alkanes in a Position-Selective Manner

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CCS Chemistry 2024年第6期6卷 1430-1438页

作者： Wen Wei Bin Wang Simon L.Homölle Jinbin Zhu Yanjun Li Tristan von Münchow Isaac Maksso Lutz Ackermann Institut für Organische und Biomolekulare Chemie Georg-August-Universität Göttingen37077 Göttingen

Catalytic C-H borylation is of prime topical importance,since easily available feedstock chemicals can thereby be transformed into valuable transient functional groups in the absence of directing ***,we disclose an iron-catalyzed C(sp^(3))-H borylation of simple,non-prefunctionalized alkanes,providing access to value-added products in a single step by means of *** power of merging photo-and electrochemistry was mirrored by ample scope and exceedingly mild reaction ***,an outstanding position-selectivity in favor of primary C(sp^(3))-H proved viable within the photoelectrochemical borylation through a chemo-selective anodic overoxidation *** ferro-photoelectrochemistry strategy avoids toxic precious transition metals,enabling C(sp^(3))-H borylations in a site-selective fashion.

关键词： photoelectrocatalysis C(sp^(3))-H borylation iron catalysis position-selectivity chlorine radical

Calibration of the DEM sliding friction and rolling friction parameters of a cohesionless bulk material

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Particuology 2024年第9期92卷 126-139页

作者： Jonatan Marín Pérez Tugrul Comlekci Yevgen gorash Donald MacKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction Particle shape