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Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.minárik m.Zemková S.Šašek J.Dittrich m.Knapek f.Lukáˇc D.Koutný J.Jaroš R.Král faculty of mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SLm).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SLm material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 mPa in tension and compression and relatively good deformability of∼9%and∼21%for the SLm and SPS materials,*** corrosion resistance of the SPS material in 0.1 m NaCl solution was superior to the SLm one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLm *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： magnesium Yttrium Powder metallurgy microstructure mechanical strength Corrosion resistance

Ultrafast magneto-optical dynamics in nickel(111)single crystal studied by the integration of ultrafast reflectivity and polarimetry probes

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Chinese Physics B 2024年第3期33卷 65-69页

作者：匡皓余军潇陈洁 h.E.Elsayed-Ali 李润泽 Peter m.Rentzepis School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China Center for Ultrafast Science and Technology Key Laboratory for Laser Plasmas (Ministry of Education)Collaborative Innovation Center of IFSA (CICIFSA)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Department of Electrical and Computer Engineering Old Dominion UniversityNorfolkVirginia 23529USA Department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTexas 77843USA

With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single *** carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of *** the other hand,the observed spin dynamics indicate a longer time of about 120 *** further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.

关键词： ultrafast spin dynamics non-equilibrium dynamics multi-probe

Design of a Novel Exoskeleton with Passive magnetic Spring Self-locking and Spine Lateral Balancing

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Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon f.Rodríguez-León Betsy D.m.Chaparro-Rico Daniele Cafolla francesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico Department of mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive Degrees of freedom(Dof).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight *** paper reports specific models and simulations to demonstrate the feasibility and effectiveness of the proposed *** experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling *** obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Trauma to the solid abdominal organs:The missed dark box of colonoscopy

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World Journal of Gastroenterology 2024年第7期30卷 624-630页

作者： mohamed h Emara Usama mazid Yasmine A Elshaer mahmoud A Elkerdawy Dilaver farooq malik Aya m mahros Department of hepatology Gastroenterologyand Infectious DiseasesKafrelsheikh UniversityKafr-Elshikh 33516Egypt Department of medicine Alyousif HospitalAlkhobar 31952Saudi Arabia

Colonoscopy is an integral part of the lower bowel care and is generally considered a potentially safe diagnostic and therapeutic procedure performed as a daycare outpatient *** is associated with different complications that are not limited to adverse events related to the bowel preparation solutions used,the sedatives used,but to the procedure related as well including bleeding and *** to the extra-luminal abdominal organs during colonoscopy are uncommon,however,serious complications related to the procedure have been reported infrequently in the *** threatening injuries to the spleen,liver,pancreas,mesentery,and urinary bladder have been reported as early as in *** injuries should not be overlooked by clinicians and *** increasing abdominal pain,abdominal distension,and hemodynamic instability in absence of rectal bleeding should raise the possibility of severe organ *** and hepatic injury following colonoscopy are usually serious and may be life *** conservative management may help,yet they usually need interventional radiology or surgical *** pancreatitis following colonoscopy is usually mild and is mostly managed *** mechanism of abdominal organ injuries during colonoscopy is not fully understood,however many risk factors have been identified,which can be classified as-organ related,procedure related,and local abdominal *** colonoscopy and prior intra-abdominal adhesions are probably the most relevant risk factors for these *** lateral position,avoidance of looping and excessive force during the procedure would probably reduce the risk of such injuries.

关键词： Colonoscopy Pancreatitis Trauma Complications Adhesions

Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

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marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.P.Nagahawatta N.m.Liyanage Thilina U.Jayawardena h.h.A.C.K.Jayawardhana Seong‑hun Jeong hyung‑Jun Kwon You‑Jin Jeon Department of marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada marine Science Institute Jeju National UniversityJeju 63333Republic of Korea functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ***-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World health ***,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently *** naturally occurring bioactive substances have been studied in the clinical setting for diverse *** intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic *** natural products(mNPs)have received increased attention in the development of novel drugs owing to their high diversity and ***,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and ***,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing mNPs and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 marine natural products Drug targets Inhibitors

Composite fractional Trapezoidal Rule with Romberg Integration

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Computer modeling in Engineering & Sciences 2024年第9期140卷 2729-2745页

作者： Iqbal m.Batiha Rania Saadeh Iqbal h.Jebril Ahmad Qazza Abeer A.Al-Nana Shaher momani Department of mathematics Al Zaytoonah University of JordanAmman11733Jordan Nonlinear Dynamics Research Center(NDRC) Ajman UniversityAjman 346United Arab Emirates Department of mathematics Faculty of ScienceZarqa UniversityZarqa13110Jordan Department of mathematics Prince Sattam Bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of mathematics The University of JordanAmman11942Jordan

The aim of this research is to demonstrate a novel scheme for approximating the Riemann-Liouville fractional integral *** would be achieved by first establishing a fractional-order version of the 2-point Trapezoidal rule and then by proposing another fractional-order version of the(n+1)-composite Trapezoidal *** particular,the so-called divided-difference formula is typically employed to derive the 2-point Trapezoidal rule,which has accordingly been used to derive a more accurate fractional-order formula called the(n+1)-composite Trapezoidal ***,in order to increase the accuracy of the proposed approximations by reducing the true errors,we incorporate the so-called Romberg integration,which is an extrapolation formula of the Trapezoidal rule for integration,into our proposed *** numerical examples are provided and compared with a modern definition of the Riemann-Liouville fractional integral operator to illustrate the efficacy of our scheme.

关键词： Composite fractional Trapezoidal rule Romberg integration

GliomaCNN: An Effective Lightweight CNN model in Assessment of Classifying Brain Tumor from magnetic Resonance Images Using Explainable AI

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Computer modeling in Engineering & Sciences 2024年第9期140卷 2425-2448页

作者： md.Atiqur Rahman mustavi Ibne masum Khan md hasib m.f.mridha Sultan Alfarhood mejdl Safran Dunren Che Department of Computer Science and Engineering Ahsanullah University of Science and TechnologyDhaka1208Bangladesh Department of Computer Science and Software Engineering The University of Western AustraliaPerthWA 6009Australia Department of Computer Science American International University-BangladeshDhaka1229Bangladesh Department of Computer Science College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia School of Computing Southern Illinois UniversityCarbondale62901USA

Brain tumors pose a significant threat to human lives and have gained increasing attention as the tenth leading cause of global *** study addresses the pressing issue of brain tumor classification using magnetic resonance imaging(mRI).It focuses on distinguishing between Low-Grade Gliomas(LGG)and high-Grade Gliomas(hGG).LGGs are benign and typically manageable with surgical resection,while hGGs are malignant and more *** research introduces an innovative custom convolutional neural network(CNN)model,*** stands out as a lightweight CNN model compared to its *** research utilized the BraTS 2020 dataset for its *** with the gradient-boosting algorithm,GliomaCNN has achieved an impressive accuracy of 99.1569%.The model’s interpretability is ensured through Shapley Additive exPlanations(ShAP)and Gradient-weighted Class Activation mapping(Grad-CAm++).They provide insights into critical decision-making regions for classification *** challenges in identifying tumors in images without visible signs,the model demonstrates remarkable performance in this critical medical application,offering a promising tool for accurate brain tumor diagnosis which paves the way for enhanced early detection and treatment of brain tumors.

关键词： Deep learning magnetic resonance imaging convolutional neural networks explainable AI boosting algorithm ablation

microbial,immune and antioxidant responses of Nile tilapia with dietary nano-curcumin supplements under chronic low temperatures

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Aquaculture and fisheries 2024年第1期9卷 57-65页

作者： mohammed f.El Basuini mohamed A.A.Zaki Abdelaziz m.El-hais mohamed G.Elhanafy Emad h.El-Bilawy Amr I.Zaineldin mohamed f.A.Abdel-Aziz Ibrahim A.Abouelsaad Ibrahim TEl-Ratel Kumbukani mzengereza Ronick S.Shadrack Islam I.Teiba faculty of Agriculture Tanta UniversityTanta31527Egypt King Salman International University South Sinai46618Egypt faculty of Agriculture Alexandria UniversityAlexandria21526Egypt Animal health Research Institute(AhRI-DOKI) Agriculture Research CenterGiza12619Egypt fish Rearing Lab. Aquaculture DivisionNational Institute of Oceanography and FisheriesAlexandria21556Egypt horticulture Department Faculty of AgricultureDamanhour UniversityDamanhur22511Egypt Department of Poultry Production Faculty of AgricultureDamietta UniversityDamietta34517Egypt Laboratory of Aquatic Animal Nutrition Faculty of FisheriesKagoshima UniversityKagoshima890-0065Japan Department of Aquatic and fisheries Science Mzuzu UniversityMzuzuPrivate Bag 201Malawi faculty of Aquaculture and marine fisheries Arish UniversityArish45516Egypt

A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).fishes(n=225;Initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in *** low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological ***,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control ***,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ***,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOD)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 *** addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYmC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin *** conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.

关键词： Nano curcumin Gastrointestinal microbiota Antioxidants Non-specific immune responses Temperature stress

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt m.Gyrdymov S.Zähter P.Tavana m.m.Günther N.Bukharskii N.Borisenko J.Jacoby X.f.Shen A.Pukhov N.E.Andreev O.N.Rosmej faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI helmholtzzentrum für Schwerionenforschung Gmbh Planckstraße 164291 DarmstadtGermany focused Energy Gmbh Im Tiefen See 4564293 DarmstadtGermany National Research Nuclear University mEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation heinrich-heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for high Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PhELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 meV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an fWhm of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical