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Effects of friction stir processing and nano-hydroxyapatite on the microstructure,hardness,degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications

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Journal of magnesium and Alloys 2024年第1期12卷 209-224页

作者： Bo Wu farazila Yusof fuguo Li Huan miao A.R.Bushroa mohd Ridha Bin muhamad Irfan anjum Badruddin mahmoud Z.Ibrahim Department of mechanical Engineering Faculty of EngineeringUniversiti MalayaKuala Lumpur 50603Malaysia Centre of Advanced manufacturing and material Processing(AmmP Centre) Universiti MalayaKuala Lumpur 50603Malaysia Center of foundation studies in Science Universiti MalayaKuala Lumpur 50603Malaysia State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China mechanical Engineering Department College of EngineeringKing Khalid UniversityAbha 61421Saudi Arabia Design and Production Engineering Faculty of EngineeringAin Shams UniversityCairo 11517Egypt

Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural ***,the rapid degradation of magnesium alloys in biological media hinders successful *** of microstructure,as well as reinforcement particles can significantly improve the degradation *** this work,multi-pass friction stir processing(fSP)was proposed to synthesize WE43/nano-hydroxyapatite(n HA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were *** subsequent fSP passes of WE43 alloy and WE43/n HA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three *** resulted in increasing the microhardness by 120%(90.86 HV0.1)and 135%(105.59 HV0.1)for the WE43 and WE43-n HA,*** is found that increasing fSP passes improved the uniform distribution of n HA particles within the composite matrix which led to improved corrosion resistance and less degradation *** corrosion rate of the fSPed WE43/n HA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(mg24Y5and mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n ***,the growing Ca-P and mg(OH)2layer formed on the surface represented a protective layer that reduced the degradation *** wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base ***,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of fSPed WE43/n HA composite after three *** results raise that the grain refinement by fSP and introduction of n HA partic

关键词： friction stir processing magnesium-based composite Nano-hydroxyapatite Corrosion behavior In-vitro bioactivity

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 711-724页

作者： f.JAZINI DORCHEH m.GHASSEmI fuel Cells and Nano Systems(fCNS)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

morphological traits explain the individual position within resource-consumer networks of a Neotropical marsupial

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Current Zoology 2024年第4期70卷 453-464页

作者： Nicholas f.de Camargo Hernani f.m.de Oliveira Juliana f.Ribeiro Amabilio J.A.de Camargo Emerson m.Vieira Laboratorio de Ecologia de Vertebrados Departamento de EcologiaInstituto de Ciencias BiologicasUniversidade de BrasiliaCP 04457BrasiliaDF70910-900Brazil Departamento de Zoologia Setor de Ciencias BiologicasUniversidade Federal do ParanaAvenida Coronel Francisco Heraclito dos Santos100CuritibaPR81531980Brazil Embrapa Cerrados Rodovia BR020km 18CP 08223PlanaltinaDE73310-970Brazil

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation *** tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian *** with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet *** relationship between individuals'position in the network and body traits,however,was independent of *** propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological ***/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more ***,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.

关键词： bodytraits centrality Cerrado Gracilinanus agilis seasonality specialization.

Carbon monoxide as C1 Building Block in fine Chemical Synthesis

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Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario J.f.Calvete Gabor mikle Laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ELKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide fine chemicals Carbonylation Hydroformylation C-H functionalization

Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.m.Gillies E.Spanswick E.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SmILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

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Computer modeling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila m.Halman mohammed J.f.Alenazi Department of Computer Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive *** amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast *** to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and *** this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe *** attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human *** can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or *** this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various *** propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS *** then evaluate the accuracy and performance of the proposed TBDC *** technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

关键词： Network resilience network management attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare

Classical taxonomy,molecular phylogeny and genetic analysis of the genus Exitianus Ball,1929(Hemiptera:Cicadellidae:Deltocephalinae)from Egypt

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Zoological Systematics 2024年第2期49卷 143-157页

作者： Rabab m.El-Hady Ahmed f.El-Sayed Survey&Taxonomy Department Plant Protection Research InstituteAgriculture Research CentreGizaEgypt microbial Genetics Department Biotechnology Research InstituteNational Research CentreGizaEgypt Egypt Center for Research and Regenerative medicine(ECRRm) CairoEgypt

Egyptian species of the leafhopper genus Exitianus Ball,1929,***(St?l,1855),***(Distant,1908),and *** Ross,1968 are ***,morphological descriptions,and a key for their identification are *** this study,we used molecular techniques to confirm morphological identification and detect phylogeny among the three Exitianus *** partial nucleotide sequences of the amplified products obtained were determined by macrogen *** nucleotide sequences of 28S rDNA and COX genes of the EGY-ARC-9,EGY-ARC-4,and EGY-ARC-5 were determined by macrogen Korea,blasted into BLAST at the National Center for Biotechnology Information website(NCBI)and compared with those deposited in the GenBank DNA *** results represented the homology percentage between the partial sequences of the 28S rRNA and COX genes from each species and related species obtained from GenBank DNA *** morphological identifications of the three Exitianus species were confirmed by molecular characterization and sequencing of 28S rDNA and COX genes and identified as ***,***,and ***,their sequences of 28srDNA and COX genes were deposited in GenBank with an accession number(LC670610,LC670607,and OQ196105)for 28srDNA gene and(LC775357,LC775358,and LC775359)for the COX gene.

关键词： Auchenorrhyncha Chaismini taxonomic 28S rDNA phylogenetic

Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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International Journal of minerals,metallurgy and materials 2024年第2期31卷 362-373页

作者： f.Akbari m.Golkaram S.Beyrami G.Shirazi K.mantashloo R.Taghiabadi m.Saghafi Yazdi I.Ansarian Department of metallurgy and material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCR).According to the results,by increasing the SCR from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the SCR also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 mPa,an in-crease in the SCR from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

Predicting short-term thromboembolic risk following Roux-en-Y gastric bypass using supervised machine learning

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1097-1108页

作者： Hassam Ali faisal Inayat Vishali moond Ahtshamullah Chaudhry Arslan Afzal Zauraiz anjum Hamza Tahir muhammad Sajeel Anwar Dushyant Singh Dahiya muhammad Sohaib Afzal Gul Nawaz Amir H Sohail muhammad Aziz Department of Gastroenterology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Department of Internal medicine Allama Iqbal Medical CollegeLahorePunjab 54550Pakistan Department of Internal medicine Saint Peter's University Hospital and Robert Wood Johnson Medical SchoolNew BrunswickNJ 08901United States Department of Internal medicine St.Dominic's HospitalJacksonMS 39216United States Department of Internal medicine Rochester General HospitalRochesterNY 14621United States Department of Internal medicine Jefferson Einstein HospitalPhiladelphiaPA 19141United States Department of Internal medicine UHS Wilson Medical CenterJohnsonNY 13790United States Division of Gastroenterology Hepatology and MotilityThe University of Kansas School of MedicineKansasKS 66160United States Department of Internal medicine Louisiana State University HealthShreveportLA 71103United States Department of Surgery University of New Mexico School of MedicineAlbuquerqueNM 87106United States Department of Gastroenterology and Hepatology The University of ToledoToledoOH 43606United States

BACKGROUND Roux-en-Y gastric bypass(RYGB)is a widely recognized bariatric procedure that is particularly beneficial for patients with class III *** aids in significant weight loss and improves obesity-related medical *** its effectiveness,postoperative care still has *** evidence shows that venous thromboembolism(VTE)is a leading cause of 30-d morbidity and mortality after ***,a clear unmet need exists for a tailored risk assessment tool for VTE in RYGB *** To develop and internally validate a scoring system determining the individualized risk of 30-d VTE in patients undergoing *** Using the 2016–2021 metabolic and Bariatric Surgery Accreditation Quality Improvement Program,data from 6526 patients(body mass index≥40 kg/m^(2))who underwent RYGB were analyzed.A backward elimination multivariate analysis identified predictors of VTE characterized by pulmonary embolism and/or deep venous thrombosis within 30 d of *** resultant risk scores were derived from the coefficients of statistically significant *** performance of the model was evaluated using receiver operating curves through 5-fold *** Of the 26 initial variables,six predictors were *** included a history of chronic obstructive pulmonary disease with a regression coefficient(Coef)of 2.54(Pf stay(Coef 0.08,Pmbosis(Coef 1.61,Pmoglobin A1c>7%(Coef 1.19,Pf 1.43,Pf 1.24,Pfficients in an algorithm that was generated for the model predicting 30-d VTE risk *** risk model's area under the curve(AUC)was 0.79[95%confidence interval(CI):0.63-0.81],showing good discriminatory power,achieving a sensitivity of 0.60 and a specificity of *** training,the same model performed satisfactorily

关键词： Roux-en-Y gastric bypass Venous thromboembolism machine learning Bariatric surgery Predictive modeling