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Near resonance vibration isolation on a levered-dual response(LEDAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： T.i.TOLUWALOJU c.K.THEiN D.HALiM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of Excellence Research and innovation institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LEDAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros i.Theocharis Nikolaos c.Koukouzas ioannis E.Zevgolis chemical Process&Energy Resources institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical Engineering National Technical University of AthensAthensGreece

A common reclamation practice for closed coal surface mines is filling them with water to form pit *** creation and sustainability of these lakes are significantly affected by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical *** the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts critical level

cancer-associated fibroblasts express cD1d and activate invariant natural killer T cells under cellular stress

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cellular & Molecular immunology 2024年第1期21卷 91-94页

作者： Shengduo Pei Jonas Sjölund Yueyun Pan Kristian Pietras Mikael c.i.Karlsson Department of Microbiology Tumor and Cell BiologyKarolinska InstitutetStockholmSweden Division of Translational cancer Research Department of Laboratory MedicineLund University Cancer CentreLund UniversityLundSweden

invariant natural killer T(iNKT)cells are part of the family of unconventional T cells,and they recognize glycolipid antigens presented on the MHc class i like molecule cD1^([1]).in humans there are five cD1 molecules named cD1a to cD1e,whereas mice use only cD1d for lipid ***,iNKT cells can elicit both cytotoxicity similarly to conventional cD8 T cells and secrete cytokines that influence the adaptive immune response including providing direct T cell help to B cells^([2]).in the context of tumors,they can use both release of granzyme B and use Fas-mediated mechanisms for killing of tumor *** iNKT cells use a restricted TcR repertoire and cD1 molecules are non-heterogenous the risk of graft vs host disease is limited and thus these T cells have been an attractive option for off the shelf immunotherapy to treat cancer^([3]).

关键词： killer cD1d cancer

Are school uniforms associated with gender inequalities in physical activity? A pooled analysis of population-level data from 135 countries/regions

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Journal of Sport and Health Science 2024年第4期13卷 590-598页

作者： Mairead Ryan Luiza i.c.Ricardo Nicole Nathan Riikka Hofmann Esther van Sluijs Medical Research council Epidemiology Unit University of CambridgeCambridge CB20QQUK Faculty of Education University of CambridgeCambridge CB28PQUK Hunter New England Population Health WallsendNSW 2287Australia School of Medicine and Public Health College of HealthMedicine and WellbeingUniversity of NewcastleCallaghanNSW 2308Australia Hunter Medical Research institute New Lambton HeightsNSW 2305Australia National centre of implementation Science University of NewcastleCallaghanNSW 2308Australia

Purpose:it is aimed to assess whether school uniforms are associated with population-level gender inequalities in physical activity,and whether associations differ by school level,country/region income,and assessment ***:An ecological study design was *** collected data about global uniform practices using an online *** searched for country/region-level estimates of school-aged youth meeting physical activity guidelines from international surveillance *** selection was conducted in duplicate using a systematic process,and a random sample of all data was checked to ensure extraction and pooling processes were *** calculated absolute and relative gender inequalities in physical activity for each *** regression examined associations between country/region-level uniform practices(binary yes/no exposure variable) and country/region-level gender inequalities in physical activity guideline compliance(absolute and relative inequalities).We investigated moderation by school level,stratified analyses by income group,and repeated primary analyses using device-measured ***:Pooling data from 135 countries/regions(n=1,089,852),we found no association between population-level uniform practices and gender inequalities in physical activity across all ages(absolute:β=-0.2;95% confidence interval(95%ci):-1.7 to 1.3,p=0.74;relative:β=0.1;95%ci:-0.1 to 0.2,p=0.51).Subgroup analysis suggested a positive association in primary school settings(absolute:β=4.3;95%ci:-0.0 to 8.6,p=0.05).Among high-income countries,absolute inequalities were significantly greater in countries/regions with uniform practices(N=37) compared to those without(N=48)(9.1(SD=3.6) vs.7.8 percentage points(SD=4.3)).Repeating analyses using device-measured data(n=32,130;N=24) did not alter our primary *** initial descriptive statistics,we found that in countries/regions where a maj ority of schools(>50%) reportedly use uniforms,there was lower compli

关键词： School policy clothing child Adolescent Accelerometer

Using fracture-based continuum modeling of coupled geomechanical-hydrological processes for numerical simulation of hydraulic fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1582-1599页

作者： Goodluck i.Ofoegbu GNO Modeling Research LLc. San AntonioTX78253USA

This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBcM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture *** simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBcM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(*** re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain *** simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density *** combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing *** are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured *** are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical *** of a single-well model are used to determine the pattern and spacing for a multiple-well *** results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than *** preexisting fractures are steeply dipping or vertical,and considering the same in situ

关键词： Discrete fracture Fracture-based continuum modeling Fracture caging High-density fracturing Hydraulic fracturing Preexisting fracture

Polio eradication surveillance in Sri Lanka,2019-2023

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Asian Pacific Journal of Tropical Medicine 2024年第6期17卷 268-272页

作者： M.A.Y.Fernando N.S.Madarasinghe c.Rangana N.Weerasinghe D.c.U.D.Weligamage J.i.Abeynayake Department of Medical Microbiology and immunology Faculty of MedicineUniversity of ColomboSri Lanka Department of Virology Medical Research InstituteColombo 08Sri Lanka Medical Research institute Colombo 08Sri Lanka

Objective:To evaluate the polio laboratory surveillance carried out from January,2019 to May,2023 by the Polio Regional Reference Laboratory,Sri ***:This retrospective study analyzed all stool samples received under the acute flaccid paralysis(AFP)and immunodeficient vaccine-derived poliovirus(VDPV)surveillance at Polio Regional Reference Laboratory,Sri Lanka from January,2019 to May,*** results of the testing methodologies were extracted from the laboratory data system,i.e.,poliovirus virus isolation,intra-typic differentiation/VDPV real time reverse transcriptase polymerase chain reaction(iTD/VDPV rRTPcR)and sequencing,along with the data on timing of reporting results,stool adequacy and *** was analyzed using descriptive ***:A total of 2141 stool samples from 1644 cases were received for AFP surveillance from Sri Lanka(93.61%),Maldives(1.52%),and immunodeficient VDPV(4.86%)*** polioviruses(19/1644,1.15%)and non-polio enteroviruses(73/1644,4.44%)were isolated,while Sabin-like 3 virus was detected in majority(12/19,63.15%)among the poliovirus *** polioviruses or circulating VDPVs were not detected among the *** all years of the study,the non-polio AFP detection rate was>1/100000 in children aged less than 15 years,whereas stool adequacy rate was>80%.All results were reported within 14 days of receipt,ensuring timely reporting as per global ***:The Polio Regional Reference Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the country through its robust laboratory surveillance,while adhering to the surveillance ***-detection of wild polioviruses and circulating VDPV during the study period reinforces the polio-free status in the country.

关键词： Poliovirus Polio laboratory surveillance Regional reference laboratory Polio eradication

Real Time Thermal image Based Machine Learning Approach for Early collision Avoidance System of Snowplows

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Journal of intelligent Learning Systems and Applications 2024年第2期16卷 107-142页

作者： fletcher Wadsworth Suresh S. Muknahallipatna Khaled Ksaibati Department of Electrical Engineering and computer Science University of Wyoming Laramie WY USA Department of civil and Architectural Engineering University of Wyoming Laramie WY USA

in an effort to reduce vehicle collisions with snowplows in poor weather conditions, this paper details the development of a real time thermal image based machine learning approach to an early collision avoidance system for snowplows, which intends to detect and estimate the distance of trailing vehicles. Due to the operational conditions of snowplows, which include heavy-blowing snow, traditional optical sensors like LiDAR and visible spectrum cameras have reduced effectiveness in detecting objects in such environments. Thus, we propose using a thermal infrared camera as the primary sensor along with machine learning algorithms. First, we curate a large dataset of thermal images of vehicles in heavy snow conditions. Using the curated dataset, two machine-learning models based on the modified ResNet architectures were trained to detect and estimate the trailing vehicle distance using real-time thermal images. The trained detection network was capable of detecting trailing vehicles 99.0% of the time at 1500.0 ft distance from the snowplow. The trained trailing distance network was capable of estimating distance with an average estimation error of 10.70 ft. The inference performance of the trained models is discussed, along with the interpretation of the performance.

关键词： convolutional Neural Networks Residual Networks Object Detection image Processing Thermal imaging

Biofabrication of nanocomposite-based scaffolds containing human bone extracellularmatrix for the differentiation of skeletal stem and progenitor cells

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Bio-Design and Manufacturing 2024年第2期7卷 121-136页

作者： Yang-Hee Kim Janos M.Kanczler Stuart Lanham Andrew Rawlings Marta Roldo Gianluca Tozzi Jonathan i.Dawson Gianluca cidonio Richard O.c.Oreffo Faculty of Medicine Bone and Joint Research GroupCentre for Human DevelopmentStem Cells and RegenerationInstitute of Developmental SciencesUniversity of SouthamptonSouthampton SO166YDUK School of Pharmacy and Biomedical Science University of PortsmouthPortsmouth PO12DTUK School of Engineering Faculty of Engineering and ScienceUniversity of GreenwichGreenwich ME44TBUK center for Life Nano-and Neuro-Science(cLN2S) Italian Institute of Technology00161 RomeItaly

Autograft or metal implants are routinely used in skeletal ***,they fail to provide long-term clinical resolution,necessitating a functional biomimetic tissue engineering *** use of native human bone tissue for synthesizing a biomimeticmaterial inkfor three-dimensional(3D)bioprintingof skeletal tissueis anattractivestrategyfor ***,human bone extracellular matrix(bone-EcM)offers an exciting potential for the development of an appropriate microenvironment for human bone marrow stromal cells(HBMScs)to proliferate and differentiate along the osteogenic *** this study,we engineered a novel material ink(LAB)by blending human bone-EcM(B)with nanoclay(L,Laponite®)and alginate(A)polymers using extrusion-based *** inclusion of the nanoﬁller and polymeric material increased the rheology,printability,and drug retention properties and,critically,the preservation of HBMScs viability upon *** composite of human bone-EcM-based 3D constructs containing vascular endothelial growth factor(VEGF)enhanced vascularization after implantation in an ex vivo chick chorioallantoic membrane(cAM)*** inclusion of bone morphogenetic protein-2(BMP-2)with the HBMScs further enhanced vascularization and mineralization after only seven *** study demonstrates the synergistic combination of nanoclay with biomimetic materials(alginate and bone-EcM)to support the formation of osteogenic tissue both in vitro and ex vivo and offers a promising novel 3D bioprinting approach to personalized skeletal tissue repair.

关键词： Extracellular matrix Nanoclay Bone 3D bioprinting

Harnessing the power of complex light propagation in multimode fibers for spatially resolved sensing

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Photonics Research 2024年第3期12卷 411-422页

作者： DARcY L.SMiTH LiNH V.NGUYEN MOHAMMAD i.REJA ERiK P.ScHARTNER HEiKE EBENDORFF-HEiDEPRiEM DAViD J.OTTAWAY STEPHEN c.WARREN-SMiTH institute for Photonics and Advanced Sensing and School of Physics Chemistry and Earth SciencesThe University of AdelaideAdelaideSA 5005Australia Australian Research council centre of Excellence for Gravitational Wave Discovery(OzGrav) AdelaideSAAustralia Future industries institute University of South AustraliaMawson LakesSA 5095Australia Laser Physics and Photonics Devices Laboratory University of South AustraliaMawson LakesSA 5095Australia

The propagation of coherent light in multimode optical fibers results in a speckled output that is both complex and sensitive to environmental *** properties can be a powerful tool for sensing,as small perturbations lead to significant changes in the output of the ***,the mechanism to encode spatially resolved sensing information into the speckle pattern and the ability to extract this information are thus far *** this paper,we demonstrate that spatially dependent mode coupling is crucial to achieving spatially resolved *** leverage machine learning to quantitatively extract the spatially resolved sensing information from three fiber types with dramatically different characteristics and demonstrate that the fiber with the highest degree of spatially dependent mode coupling provides the greatest accuracy.

关键词： fiber spatially resolved