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Analysis of the biotribological behavior for the Stainless Steel/Polyethylene Contact Using a Knee Prosthesis Simulator

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Journal of bionic Engineering 2012年第1期9卷 59-65页

作者： M. boujelbene S. Dhouibi M. Kharrat M. Dammak Laboratoire des Systkmes Electromeeaniques Ecole Nationale d＇Ingenieurs de Sfax Route de Soukra km 35 B.P. 1173 3038 Sfax Tunisia Institut Superieur de Gestion Industrielle de Sfax Route de Mharza Km 15 B.P. 954 3018 Sfax Tunisia Faeulte des Sciences de Gafsa Campus Universitaire Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Institut Preparatoire aux Etudes d＇Ingenieurs de Sfax Route de Menzel Chaker Km 05 B.P. 1172 3018 Sfax Tunisia

In this work, a friction and wear simulator was used to reproduce the Anterior-Posterior （AP） sliding and the Flex- ion-Extension （FE） rotation generated in the knee joint during human gait cycle. We chose to simplify the contact geometry between the Total Knee Arthroplasty （TKA） femoral component and tibial insert. A 304L stainless steel cylinder which replaces the femoral component was loaded onto a flat High Density Polyethylene （HDPE） block which replaces the tibial insert. The tribological behavior of the considered contact was analyzed by tracking the number of cycles, the friction coefficient, the roughness of the wear track on HDPE, the HDPE weight loss and the damage mechanisms. The friction coefficient shows a gradual increase with the number of cycles for both AP and FE kinematics. The evolution of friction coefficient with the number of cycles is not affected by the value of the imposed normal load in the case of AP sliding. For the FE rotation, decreased friction coefficient is obtained when the imposed normal load increases. For both considered AP and FE kinematics, the roughness of the wear track on the HDPE is not affected by the imposed normal load. It shows a progressive decrease when the number of cycles increases. The wear of HDPE obeys the Archard law and the wear coefficient increases with the normal force. For a given value of normal load, the obtained wear coefficient for the AP sliding is larger than that obtained for FE rotation. A predominant adhesive wear mechanism was identified for both AP and FE kinematics. Under the same normal load, damage development in terms of plastic deformation, micro-cracking and debonding is more pronounced for the AP sliding if compared with the FE rotation. For a given kinematics, the damage severity increases with the normal load. This finding is in good agreement with the predicted values of the wear coefficient according to the Archard law.

关键词： knee prosthesis polyethylene friction wear gait cycle

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A detailed Lower Triassic conodont biostratigraphy and its implications for the GSSP candidate of the Induan–Olenekian boundary in Chaohu,Anhui Province

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Progress in Natural Science:Materials International 2008年第1期18卷 79-90页

作者： Michael J.Orchard Canada V6b5J3 Geological Survey of Canada 101-605 Robson Street Vancouver

Chaohu is located in a deep part of carbonate ramp on the Lower Yangtze block,which belonged to the low-latitude eastern Tethyan archipelago during the Early *** were very rich in the Lower Triassic of ***,ammonoids,conodonts were very common throughout the Lower Triassic,while fish fossils were generally rich in some beds of the upper *** is one of the most typical sections for the Early Triassic chronostratigraphy in the *** various fossils had been studied in the 1980s and 1990s,recent studies based upon new and more detailed collections from the Lower Triassic of Chaohu showed that the conodont zonation needs *** collected Lower Triassic conodont fossils from continuous sections of the West Pingdingshan,North Pingdingshan and South Majiashan,Chaohu,Anhui Province,and updated zonations were made for each *** conodont zones have been dis- *** are,in ascending order,Hindeodus typicalis zone,Neogondolella krystyni zone,Neospathodus kummeli zone,Neospath- odus dieneri zone,Neospathodus waageni zone,Neospathodus pingdingshanensis zone,Neospathodus homeri zone,and Neospathodus anhuinensis *** first occurrence of Neospathodus waageni eowaageni of the *** subzone(*** base of the *** zone)is suggested as the marker to define the Induan–Olenekian boundary.

关键词： Conodont biostratigraphy Conodont zonation Lower Triassic Induan–Olenekian Chaohu in Anhui Province

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Consolidation and dynamics of 3D unsaturated porous seabed under rigid caisson breakwater loaded by hydrostatic pressure and wave

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Science China(Technological Sciences) 2012年第8期55卷 2362-2376页

作者： YE JianHong JENG DongSheng CHAN A H C Division of Civil Engineering University of DundeeDundee DD14HNUK Department of Civil Engineering University of BirminghamBirminghamB152TTUK

In this study,based on the dynamic biot＇s theory ＂u-p＂ approximation,a 3D finite element method（FEM） numerical soil model is developed,in which the Generalized Newmark-β method is adopted to determine the time *** developed 3D FEM soil model is a part of the coupled model PORO-WSSI 3D for 3D wave-seabed-marine structures interaction problem,and is validated by the analytical solution proposed by Wang（2000） for a laterally infinite seabed loaded by a uniform *** adopting the developed 3D soil model,the consolidation of seabed under a caisson breakwater and hydrostatic pressure is *** numerical results show that the caisson breakwater built on seabed has very significant effect on the stresses/displacements fields in the seabed foundation after the transient deformation and primary consolidation are *** parametric study indicates that the Young＇s modulus E of seabed is the most important parameter to affect the settlement of breakwater,and the displacement fields in seabed *** the consolidation status as the initial condition,the interaction between ocean wave,caisson breakwater and seabed foundation is briefly *** 3D ocean wave is determined by solving the Navier-Stokes equations with finite volume method（FVM）.The numerical results indicate that there is intensive interaction between oceean wave, caisson breakwater and seabed foundation; and the breakwater indeed can effectively block the wave energy propagating to the coastline.

关键词： consolidation wave-seabed-breakwater interaction unsaturated seabed breakwater biot's theory Navier-Stokes equation

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ROCO:Using a Solid State Drive Cache to Improve the Performance of a Host-Aware Shingled Magnetic Recording Drive

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Journal of Computer Science & Technology 2019年第1期34卷 61-76页

作者： Wen-Guo Liu Ling-Fang Zeng Dan Feng Kenneth b.Kent School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430074China Faculty of Computer Science University of New BrunswickFrederictonE3B 5A3Canada

Shingled magnetic recording (SMR)can effectively increase the capacity of hard disk drives (HDDs).Hostaware SMR (HA-SMR)is expected to be more popular than other SMR models because of its backward compatibility and new SMR-specific ***,an HA-SMR drive often suffers performance degradation under write-intensive workloads because of frequent non-sequential writes buffered in the disk *** non-sequential writes mainly come from update writes,small random writes and out-of-order *** this paper,we propose a hybrid storage system called ROCO which aims to use a solid state drive (SSD)cache to improve the performance of an HA-SMR *** reorders out-of-order writes belonging to the same zone and uses the SSD cache to absorb update writes and small random *** also design a data replacement algorithm called CREA for the SSD *** first conducts zone-oriented hot/cold data identification to identify cold-cached zones and hot-cached zones,and then evicts data blocks belonging to colder zones with higher priorities that can be sequentially written or written through host-side read-modify-write *** gives the lowest priority to data blocks belonging to the hottest-cached zone that have to be non-sequentially *** results show that ROCO can effectively reduce non-sequential writes to the HA-SMR drive and improve the performance of the HA-SMR drive.

关键词： solid state reordering zone-oriented drive (SSD)cache host-aware shingled magnetic recording (HA-SMR)drive zone-oriented block hot/cold data identification data replacement algorithm

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RObO-SPOT:Detecting Robocalls by Understanding User Engagement and Connectivity Graph

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big Data Mining and Analytics 2024年第2期7卷 340-356页

作者： Muhammad Ajmal Azad Junaid Arshad Farhan Riaz College of Comnputer Science Birmingham City UniversityBirminghamB55JUUK School of Computer Science University of LincolnLincolnLN67TSUK

Robo or unsolicited calls have become a persistent issue in telecommunication networks,posing significant challenges to individuals,businesses,and regulatory *** calls not only trick users into disclosing their private and financial information,but also affect their productivity through unwanted phone ringing.A proactive approach to identify and block such unsolicited calls is essential to protect users and service providers from potential ***,this paper proposes a solution to identify robo-callers in the telephony network utilising a set of novel features to evaluate the trustworthiness of callers in a *** trust score of the callers is then used along with machine learning models to classify them as legitimate or *** use a large anonymized dataset(call detailed records)from a large telecommunication provider containing more than 1 billion records collected over 10 *** have conducted extensive evaluation demonstrating that the proposed approach achieves high accuracy and detection rate whilst minimizing the error ***,the proposed features when used collectively achieve a true-positive rate of around 97%with a false-positive rate of less than 0.01%.

关键词： social network analysis reputation unwanted calls robo-callers telephone network Spam Over Internet Technology(SPIT)

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Enrichment of retinal ganglion and Müller glia progenitors from retinal organoids derived from human induced pluripotent stem cells-possibilities and current limitations

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World Journal of Stem Cells 2020年第10期12卷 1171-1183页

作者： Kristine Karla Freude Sarkis Saruhanian Alanna McCauley Colton Paterson Madeleine Odette Annika Oostenink Poul Hyttel Mark Gillies Henriette Haukedal Miriam Kolko Department of Veterinary and Animal Sciences Group of Stem Cell Models for Studies of Neurodegenerative DiseasesSection for Pathobiological SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg 1870Denmark Department of Drug Design and Pharmacology University of CopenhagenCopenhagen 2100Denmark Save Sight Institute South BlockSydney Eye HospitalSydney 2000Australia Department of Ophthalmology Copenhagen University HospitalRigshospitalet-GlostrupGlostrup 2600Denmark

bACKGROUND Retinal organoids serve as excellent human-specific disease models for conditions affecting otherwise inaccessible retinal tissue from *** permit the isolation of key cell types affected in various eye diseases including retinal ganglion cells(RGCs)and Müller *** To refine human-induced pluripotent stem cells(hiPSCs)differentiated into threedimensional(3D)retinal organoids to generate sufficient numbers of RGCs and Müller glia progenitors for downstream *** In this study we described,evaluated,and refined methods with which to generate Müller glia and RGC progenitors,isolated them via magnetic-activated cell sorting,and assessed their lineage stability after prolonged 2D *** progenitor populations were characterized via quantitative PCR and immunocytochemistry,and the ultrastructural composition of retinal organoid cells was *** Our study confirms the feasibility of generating marker-characterized Müller glia and RGC progenitors within retinal *** retinal organoids can be dissociated and the Müller glia and RGC progenitor-like cells isolated via magnetic-activated cell sorting and propagated as *** Enrichment of Müller glia and RGC progenitors from retinal organoids is a feasible method with which to study cell type-specific disease phenotypes and to potentially generate specific retinal populations for cell replacement therapies.

关键词： Human induced pluripotent stem cells Retinal organoids Retinal ganglion cells Müller glia Progenitors Cell-type enrichment

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An Econometric Analysis of Cotton Production Technologies in Harran Plain, Turkey： Translog versus Cobb-Douglas Functions

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Journal of Agricultural Science and Technology(b) 2011年第3期1卷 420-427页

作者： T. Isgin R. Ozel A. bilgic S. Ipekcioglu Department of Agricultural Economics University of Harran Osmanbey Campus Block D-52 Sanliurfa 63100 Turkey Soil-Water Resources and Agricultural Research Institute for the Southeastern Anatolia Project Sanliurfa 63300 Turkey

This research explores the question of how the three production factors, capital, labor, and land may impact the current level of cotton output on the Harran Plain, a major cotton production area in Turkey. The objective of this paper is to estimate a Translog production function and compare the results to those from a Cobb-Douglas specification. Nested tests we performed resulted in the conclusion that the constant returns to scale, weak separability and Cobb-Douglas hypotheses are all satisfied. Thus the Cobb-Douglas specification is a superior functional form yielding results more robust than those from the translog model. Dwelling on Cobb-Douglas estimation results, farm size is found the most influential variable determining cotton output, followed by the variable representing capital as the second influential. Results also demonstrate that the returns-to-scale parameter calculated for this sample is not statistically different from unity, suggesting that cotton production technology in this region exhibits constant returns to scale. This result is consistent with current literature findings that render support to an inverse relationship between farm size and productivity in developing countries.

关键词： Cotton translog model cobb-douglas model weak separability Turkey constant returns to scale.

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Cretaceous Deepwater Lacustrine Dedimentary Sequences from the Northernmost South China block, Qingdao, China

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Journal of Earth Science 2014年第2期25卷 241-251页

作者： Tuoyu Wu Yongtao Fu Department of Earth and Environmental Sciences University of Winsor N9B 3P4Canada Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences

A sequence of terrigenous siliciclastic rocks crop out at baxiandun, Qingdao, near the Mesozoic collisional boundary between North China block （NCb） and South China block （SCb）. These low-grade metamorphosed siliciclastic rocks are dominated by greywacke with shale, man- ganiferous fine-grained sandstone, arkose and conglomerate layers. There are two basic interpreta- tions about the formation of these rocks. One considered that this sequence was formed within NCb, and is part of the Cretaceous Laiyang Group and Qingshan Group fluvial facies and volcanic debris facies, as shown on the Shandong Regional Geological Map. Another opinion suggested that these rocks represent turbidity depositional systems in the slope and the basin facies was mainly deposited in Ordovician. based on field observation, petrological analysis, and most importantly, geochemical results in this study, the sedimentary strata at baxiandun Section mainly consist of siltstone, sand- stone and mudstone lithologies. They are dominated by deepwater debris and turbidity deposits in the slope and base of a lake. The U-Pb detrital zircon dating of the rocks at the baxiandun Section indicates that the source rocks are very complex and their ages are varied from Archean to Early Cretaceous. The youngest age of the terrigenous detritus could represent the age of the sedimentary strata. Therefore, we infer that the sedimentary rocks belong to Early Cretaceous deepwater lacus- trine sedimentary sequences and have multiple sources origined from the erosion of the Sulu UHP orogen and South China block margin.

关键词： Cretaceous turbidite deepwater lacustrine detrital zircon South China block.

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In vitro Safety Evaluation and Anticlastogenic Effect of bacoMind^(TM) on Human Lymphocytes

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biomedical and Environmental Sciences 2008年第1期21卷 7-23页

作者： DIPANWITA DUTTA DEb PREETI KAPOOR R. P. DIGHE R. PADMAJA M. S. ANAND P. D'SOUZA M. DEEPAK b. MURALI AMIT AGARWAL Natural Remedies Pvt. Ltd 19 K. M. Stone Hosur Road Plot No. 5B Veerasandra Indl. Area Bangalore 560100 India

Objective bacoMind^TM （bM） is a standardized extract of bacopa monnieri, which belongs to the family Scrophulariaceae and is a creeping annual plant found throughout the Indian subcontinent. It has been used by Ayurvedic medicinal practitioners in India for almost 3000 years and is classified as a medharasayana, a substance which improves memory and intellect. With the widespread traditional use as well as scientific validation of bacopa monnieri for nootropic activity, a bioactive-rich unique phytochemical composition-bacoMind^TM was developed from b. monnieri for use as a cognition and memory enhancing agent. The present study aimed to investigate the in vitro toxicity of this formulation of bacoMind^TM on human lymphocytes and to rule out its possible contribution to mutagenicity. Methods In the present investigation the active ingredients present in bM were identified and quantified by high performance liquid chromatography （HPLC） and high performance thin-layer chromatography （HPTLC）. Antioxidant and anticlastogenic properties of bM were studied in vitro with and without metabolic activation. Doses of bM were chosen on the basis of mitotic index （MI） and cytokinesis-block proliferation index （CbPI）. Clastogenicity assays were performed at 31.2 μg/mL, 62.5 μg/mL, and 125 μg/mL, while the Salmonella reverse mutation assay （Ames test） was performed at doses of 61.72, 185.18, 555.55, 1666.67, and 5000.00 μg/plate. Results HPLC and HPTLC analysis of bM revealed the presence of bacoside A3. bacopaside Ⅰ, bacopaside Ⅱ, jujubogenin isomer of bacopasaponin C, bacosine, luteolin, apigenin, bacosine, and β-sitosterol D glucoside. bM demonstrated significant antioxidant activity. The number of chromosomal aberrations and the frequency of micronuclei induced by bM were not statistically significant up to a dose of 62.5 μg/mL. A subsequent dose of 125 μg/mL prior to metabolic activation induced mild clastogenicity, but it was found to be biologically insignificant as this ef

关键词： bacoMind^TM Cytotoxicity Chromosomal aberration Ames test Micronucleus, Clastogens Antioxidant High performance liquid chromatography High performance thin-layer chromatography (HPTLC)

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Community microgrid:an approach towards positive energy community in an urban area of Dhaka,bangladesh

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Clean Energy 2023年第4期7卷 926-939页

作者： Mohammad Zeyad S.M.Masum Ahmed Sayeed Hasan Dewan Mahnaaz Mahmud Energy and Technology Research Division Advanced BioinformaticsComputational Biology and Data Science LaboratoryBangladesh(ABCD LaboratoryBangladesh)House:24Road:01Block:BHalishaharChattogram 4226Bangladesh School of Engineering and Physical Sciences(EPS) Heriot-Watt UniversityCampus The AvenueEdinburghScotland EH144ASUK Department of Energy Engineering University of the Basque Country(UPV/EHU)Ingeniero Torres Quevedo Plaza1BilbaoBiscay 48013Spain Department of Electrical Electronic and Control EngineeringSchool of Industrial EngineeringUniversity of ExtremaduraCampus UniversitarioAv.de Elvass/nBadajozBadajoz 06006Spain Centre for Research on Geography ResourcesEnvironmentEnergy and Networks(Green)Bocconi UniversityVia Roentgen 1MilanoLombardy 20136Italy Control and Robotics(CORO) Ecole Centrale De Nantes1 Rue de la No?44300 NantesFrance

The pollution and toxic greenhouse gases produced by fossil fuel combustion are troubling as global energy demand continues to *** mitigate the consequences of global warming,a transition to sustainable energy sources is *** manuscript presents a feasible community microgrid design in Hazaribagh,Dhaka based on meteorological data that leads to photovoltaic installation on the rooftop of a local community *** study shows a microgrid design of a system with the lowest cost of energy and a large renewable fraction,which is analysed using the HOMER Pro *** real-time data,analysis of the system cost,cost of energy,renewable fraction,unmet load,energy purchased and energy sold is discussed.A suitable case for electrification is also identified and presented for the selected *** proposed case yields a cost of energy of$0.0357/kWh,which is 52%less than the current tariff rate,with a 70%renewable *** study will provide people in this community with more green energy at a lower cost;in addition,this designed microgrid sells additional energy to the grid to avoid possible power *** potential for a positive energy community is also investigated in terms of energy consumption and renewable output of the planned microgrid.

关键词： cost of energy microgrid positive energy community renewable fraction

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