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Paleo-Mesoarchean sedimentary record in the Dharwar craton,india:implications for Archean ocean oxygenation

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geoscience Frontiers 2024年第1期15卷 126-154页

作者： g.Harshitha c.Manikyamba M.Santosh cheng-Xue Yang A.Keshav Krishna V.V.Sesha Sai i.Panduranga Reddy c.iR-National geophysical Research institute(NgRi) Uppal RoadHyderabad 500007India Department of geology Osmania UniversityHyderabad 500007India School of Earth Science and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA5005Australia Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea geological Survey of india State UnitNagpurIndia

The early Archean oceans were marked by significant redox changes which have subsequently shaped the Earth’s *** chemical sediments of banded iron and Manganese formations provide important geochemical proxies for these historical shifts in the redox conditions and to trace the ancient sedimentation patterns and *** this study,we investigate the proto-ore of the Archean Mn-formations of the Sandur,c.itradurga and Shimoga greenstone belts of Dharwar craton of southern Peninsular india,which is geochemically characterised as quartz arenites,Mn-arenites,Fe-arenites,Mn-argillites and *** geochemical systematics suggest their deposition in shallow to deeper shelf in the Archean *** detrital zircon U-Pb systematics of Mn arenites and argillites indicate their maximum depositional age of 3230±52 Ma representing the oldest onset of sedimentation during the Paleo-Mesoarchean timeframe in the c.itradurga group of Dharwar *** detrital influx proxies suggest variations in sedimentation rates associated with the Archean transgressive-regressive cycles and fluctuating hydrodynamic conditions,together reflec.ing an increasing trend in the contributions of recycled sediment from Sandur to c.itradurga and Shimoga greenstone *** available detrital zircon ages of the Mn arenites and argillites from these greenstone belts indicate a~600 Ma prolonged period of Mn deposition for which high-T hydrothermal fluids from Archean mid-oceanic ridges supplied the *** trace element compositions of the concordant detrital zircons suggest 3.3-3.1 ga Dharwar basement TTg/granitoid source which is corroborated by the zircon crystallization temperatures of 690-820℃.The source-normalisedα-dose rates of the detrital zircons signify greater degrees of sediment transport and multi-cycle nature which correspond to the earliest episode of crustal growth in the indian sub-continent associated with the Mesoarchean Ur supercontinent.T

关键词： Mn-arenites-argillites Dharwar craton Zircon U-Pb geochronology Passive margin sediments Ocean oxygenation

Post processing of additive manufactured Mg alloys:current status,challenges,and opportunities

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Journal of Magnesium and Alloys 2024年第4期12卷 1283-1310页

作者： Nooruddin Ansari Fatima ghassan Alabtah Mohammad i.Albakri Marwan Khraisheh Mechanical Engineering Program Texas A&M University at QatarP.O.Box 23874DohaQatar

Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight *** are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to *** ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflec.ing a transformation in the manufacturing ***,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification *** leads to defects such as porosity,lack of fusion,crac.ing,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg *** address these issues,post-processing of AM Mg alloys are often needed to make them suitable for *** present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,fric.ion stir processing,and surface *** utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also *** post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are ***,future prospects and research direc.ions are proposed.

关键词： Magnesium alloy Additive manufacturing Post-processing Heat treatment HiP

Physical ac.ivity and amyloid beta in middle-aged and older adults:A systematic review and meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 133-144页

作者： María Rodriguez-Ayllon Patricio Solis-Urra c.istina Arroyo-ávila Miriam álvarez-Ortega Pablo Molina-garcía c.istina Molina-Hidalgo Manuel gómez-Río Belinda Brown Kirk i.Erickson irene Esteban-cornejo Department of Epidemiology Erasmus University Medical Center RotterdamRotterdamGD 3015the Netherlands Department of Physical Education and Sports Faculty of Sport SciencesSport and Health University Research Institute(iMUDS)University of GranadaGranada 18071Spain Faculty of Education and Social Sciences Universidad Andres BelloVina del Mar 2531015Chile Department of Nuclear Medicine Virgen de las Nieves University HospitalInstitute of Biosanitary Research of Granada(IBS)Granada 18014Spain Physical Medicine and Rehabilitation Service Virgen de las Nieves University HospitalInstitute of Biosanitary Research of Granada(IBS)Granada 18014Spain Department of Psychology University of PittsburghPittsburghPA 15260USA centre for Healthy Ageing Health Futures InstituteMurdoch UniversityMurdochWA 6150Australia School of Medical and Health Sciences Edith Cowan UniversityJoondalupWA 6027Australia Advent Health Research institute Neuroscience Institute OrlandoOrlandoFL 32803USA Physiopathology of Obesity and Nutrition Research center(ciBERobn) Institute of Health Carlos Ⅲ(ISCⅢ)Madrid 28029Spain

Background:One of the pathological hallmarks distinguishing Alzheimer’s disease from other dementias is the accumulation of amyloid beta(Aβ).Higher physical ac.ivity is associated with decreased dementia risk,and one potential path could be through Aβlevels *** aimed to explore the relationship between physical ac.ivity and Aβin middle-aged and older ***:A systematic search of PubMed,Web of Science,PsyciNFO,cochrane central Register of controlled Trials,and SPORTDiscus was performed from inception to April 28,*** were eligible if they included physical ac.ivity and Aβdata in adults aged 45 years or ***-level metaanalyses of intervention and observational studies were performed to examine the role of physical ac.ivity in modulating Aβ***:in total,37 articles were included(8 randomized controlled trials,3 non-randomized controlled trials,4 prospec.ive longitudinal studies,and 22 cross-sec.ional studies).The overall effect size of physical ac.ivity interventions on changes in blood Aβwas medium(pooled standardized mean difference=-0.69,95%confidence interval(95%ci):-1.41 to 0.03;i^(2)=74.6%).However,these results were not statistically significant,and there were not enough studies to explore the effects of physical ac.ivity on cerebrospinal fluid(cSF)and brain Aβ.Data from observational studies were examined based on measurements of Aβin the brain using positron emission tomography scans,cSF,and *** physical ac.ivity was positively associated with Aβonly in the cSF(Estimate r=0.12;95%ci:0.05-0.18;i^(2)=38.00%).conclusion:Physical ac.ivity might moderately reduce blood Aβin middle-aged and older ***,results were only near statistical significance and might be interpreted with caution given the methodological limitations observed in some of the included *** observational studies,higher levels of physical ac.ivity were positively associated with Aβonly in ***,further research is needed t

关键词： Aging cognitive impairment Dementia Exercise PET

immunotherapy in gastric cancer with liver metastasis:challenges and opportunities

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World Journal of gastrointestinal Surgery 2024年第6期16卷 1513-1516页

作者： Murat Bardakçi Yakup Ergun Department of Medical Oncology Diyarbakır Gazi Yasargil Training and Research HospitalDiyarbakir 021000KayapinarTürkiye Department of Medical Oncology Antalya City HospitalAntalya 07080Türkiye

in this editorial,we review the article by Liu et al published in the World Journal of gastrointestinal Surgery investigating the efficacy and safety of immunotherapy in patients with gastric cancer(gc)and liver ***,the fifth most com-monly diagnosed malignancy worldwide,presents a significant challenge due to its multifactorial etiology and a grim prognosis for unresectable or recurrent *** advent of immune checkpoint inhibitors(icis)has revolutionized oncology;yet liver metastasis has been associated with reduced response rates,progression-free survival,and overall survival in various *** che-ckMate-649 and KEYNOTE-859 trials demonstrated promising results with icis in advanced gc,particularly in patients with liver ***,a meta-analysis of liver metastatic solid tumors revealed worse outcomes with icis,high-lighting the need for further *** combined therapies,including icis with local treatments,show promise in improving outcomes,the nuanced landscape of icis in liver metastatic gc necessitates continued research for robust *** current contradic.ions in the literature underscore the impor-tance of cautious interpretation and the exploration of tailored approaches to enhance c.inical efficacy in this challenging patient population.

关键词： gastric cancer Liver metastasis immunotherapy immune checkpoint in-hibitors Transarterial chemoembolization Tumor microenvironment

Nanozyme catalysis in a crowded environment:The impact of diffusion and surface shielding

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Nano Research 2024年第7期17卷 5795-5800页

作者： Vasily g.Panferov Juewen Liu Department of chemistry Waterloo Institute for NanotechnologyWaterlooOntario N2L 3G1Canada

Nanozymes are widely used in various applications as nanosized catalysts for replacing *** accurate estimation of the catalytic ac.ivity of nanozymes in real conditions is *** this article,for the first time,we systematically studied the effect of macromolecular molecules co-existing in the real system on the oxidoreductase(peroxidase,oxidase,and catalase)-mimic.ing nanozymes made of a gold nanoparticle core and a platinum shell,Prussian Blue,Mn2O3 and coO *** were made with horseradish *** distinguished two main mechanisms of the negative impact of macromolecules on nanozyme catalysis—slowed diffusion and surface shielding of *** the first mechanism is typical for enzymes,the second one is specific only for *** the mechanisms is essential for developing approaches to reduce the unavoidable impact of macromolecules for various analytical and biomedical applications.

关键词： molecular crowding biosensors nanoparticles

VR-based digital twin for remote monitoring of mining equipment:Arc.itecture and a case study

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 100-112页

作者： Jovana PLAVŠiĆ ilija MiŠKOViĆNorman BKeevil Norman B.Keevil institute of Mining Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada

Background Traditional methods for monitoring mining equipment rely primarily on visual inspec.ions,which are time-consuming,inefficient,and *** article introduces a novel approach to monitoring mission-c.itical systems and services in the mining industry by integrating virtual reality(VR)and digital twin(DT)***-based DTs enable remote equipment monitoring,advanced analysis of mac.ine health,enhanced visualization,and improved decision *** This article presents an arc.itecture for VR-based DT development,including the developmental stages,ac.ivities,and stakeholders involved.A case study on the condition monitoring of a conveyor belt using real-time synthetic vibration sensor data was conducted using the proposed *** study demonstrated the application of the methodology in remote monitoring and identified the need for further development for implementation in ac.ive mining *** article also discusses interdisciplinarity,choice of tools,computational resources,time and cost,human involvement,user acceptance,frequency of inspec.ion,multiuser environment,potential risks,and applications beyond the mining *** The findings of this study provide a foundation for future research in the domain of VR-based DTs for remote equipment monitoring and a novel application area for VR in mining.

关键词： Virtual reality Digital twin condition monitoring Mining equipment

Solar-driven cO_(2) conversion to methane and methanol using different nanostructured cu_(2)O-based catalysts modified with Au nanoparticles

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Journal of Energy chemistry 2024年第4期91卷 287-298页

作者： João Angelo Lima Perini Lilian D.Moura Torquato Juliana Fde Brito gustavo A.Andolpho Mateus A.gonçalves Leonardo D.De Angelis Lucas D.germano Susana i.córdoba de Torresi Teodorico c.Ramalho Maria V.Boldrin Zanoni São Paulo State University(UNESP) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil National institute of Alternative Technologies for Detec.ion Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil Laboratory of Molecular Modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil Department of chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work desc.ibes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduc.ion of cO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest produc.ion yield was ac.ieved using a TNT@PDA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be cu_(2)O facet-dependent,with cubic structures leading to greater conversion of cO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured cu_(2)O surface was mainly important for *** func.ional theory(DFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PDA/Nc/Au40%electrode for cH4generation to the formation of an OcH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(gc-MS)demonstrated that13cO_(2)was the source for photoelectrocatalytic generation of13cH3OH and13cH313cH2OH.

关键词： cu_(2)O nanocubes Photoelectrocatalysis Polydopamine cO_(2) photoelectroreduc.ion DFT calculations

Analysis of the discrete contact characteristics based on the greenwood-Williamson model and the localization principle

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Fric.ion 2024年第5期12卷 1042-1056页

作者： Anastasiya A.YAKOVENKO irina g.gORYAcHEVA ishlinsky institute for Problems in Mechanics RAS Moscow119526Russia

The contact of a rigid body with nominally flat rough surface and an elastic half-space is *** solve the contact problem,the greenwood-Williamson statistical model and the localization principle are *** developed contact model allows us to investigate the surface approach and the real contact area with taking into account the asperities *** is shown that the mutual influence of asperities changes not only contact characteristics at the macroscale,but also the contact pressure distribution at the *** follows from the results,the inclusion in the contact model of the effect of the mutual influence of asperities is especially significant for studying the real contact area,as well as the contact characteristics at high applied *** results calculated according to the proposed approach are in a good agreement with the experimentally observed effects,i.e.,the real contact area saturation and the additional compliance exhaustion.

关键词： surface roughness elasticity greenwood-Williamson model localization principle asperity interac.ion

control system design for a pressure-tube-type superc.itical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： M.Hajipour g.R.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable ***,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A superc.itical water reactor(ScWR)is a fourth-generation conceptual *** an ScWR,the non-linear dynamics of the reactor require a controller capable of control-ling the *** this study,a pressure-tube-type ScWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled *** an ScWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power *** point kinetics equations with three groups of delayed neutrons were used in the ***-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the Pi controllers speci-fied in previous *** controlled parameters were reactor power,steam temperature,and ***,for these parameters,the Pi controller had certain instabilities in the presence of *** classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering *** was highly accurate and stable and had a small computational *** reality,it followed the desired values without oscillations and chattering.

关键词： Superc.itical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model