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synthesis of coral-like structures of Pr-Yb co-doped YIG: structural,optical, magnetic and antimicrobial properties

Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra s.castro-lopes J.Matilla-Arias Idglan s.de Lima Edson C.silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDs) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against s. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

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snapshot survey of the Presence of Perfluoroalkyl substances in Products, Articles, and the Environment in Ecuador

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Engineering 2024年第6期37卷 49-61页

作者： Heidelore Fiedler Luis Vega-Bustillos Jenny Arias-Pastrano Lander Vinicio Pérez-Aldás Jose castro-Díaz MTM Research Centre School of Science and TechnologyÖrebro UniversityÖrebro 70182Sweden Undersecretariat of Environmental Quality Ministry of EnvironmentWater and Ecological Transition of EcuadorQuito 170525Ecuador Department of Environmental Chemistry The Technical University of AmbatoHuachi CampusAmbato 180207Ecuador Alternativavision Ambiental Cia.Ltda. Mexico 03100Mexico

The stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production,import,or export of the POPs listed in Annexes A,B,or C;provide information to registers;maintain inventories;and monitor the presence of POPs in the *** the broader context of international chemicals and waste management,producer responsibilities,harmonized reporting,and compliance with national and international regulations,Ecuador has addressed the newly listed group of perfluorinated alkyl substances(PFAs)in its national implementation plan and sent selected products from its national market for PFAs *** products analyzed came from the initially listed fields of specific exemptions and acceptable purposes,including:fire-fighting foams;photographic aids;greasers/degreasers;various kinds of paper/packaging;textiles;and leather,coatings,cleaners,metal plating,and *** results showed that the three PFAs presently listed in the stockholm Convention could be quantified in only a few samples;additional PFAs,not yet listed in the Convention also had low detection *** the number of samples was limited,the samples covered a large spectrum of sample matrices,making it possible to conclude that—once these products become waste and are regulated under the Basel Convention—they would not constitute a disposal ***,verification of the presence of PFAs in products on the market is expected to pose an analytical challenge for both,developed and developing countries.

关键词： Emerging or newly listed POPs stockholm Convention Products and articles PFAs analysis Developing countries

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Colorectal cancer screening:A review of current knowledge and progress in research

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1119-1133页

作者： sara Ramos lopes Claudio Martins Inês Costa santos Madalena Teixeira Élia Gamito Ana Luisa Alves Department of Gastroenterology Centro Hospitalar de SetúbalSetúbal 2910-446Portugal

Colorectal cancer(CRC)is one of the most prevalent malignancies worldwide,being the third most commonly diagnosed malignancy and the second leading cause of cancer-related deaths *** the progress in screening,early diagnosis,and treatment,approximately 20%-25%of CRC patients still present with metastatic disease at the time of their initial ***,the burden of disease is still expected to increase,especially in individuals younger than 50 years old,among whom early-onset CRC incidence has been *** and early detection are pivotal to improve CRC-related *** is well established that CRC screening not only reduces incidence,but also decreases deaths from *** screening strategies have proven effective in decreasing both CRC incidence and mortality,though variations in efficacy have been reported across the ***,uncertainties persist regarding the optimal screening method,age intervals and ***,adherence to CRC screening remains globally *** recent years,emerging technologies,notably artificial intelligence,and non-invasive biomarkers,have been developed to overcome these ***,controversy exists over the actual impact of some of the new discoveries on CRC-related outcomes and how to effectively integrate them into daily *** this review,we aim to cover the current evidence surrounding CRC *** will further critically assess novel approaches under investigation,in an effort to differentiate promising inno-vations from mere novelties.

关键词： Colorectal cancer screening Review Oncology Artificial intelligence

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Renewable Polymers in Biomedical Applications:From the Bench to the Market

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Journal of Renewable Materials 2024年第4期12卷 643-666页

作者： Rauany Cristina lopes Tamires Nossa Wilton Rogério Lustri Gabriel Lombardo Maria Inés Errea Eliane Trovatti Department of Health and Biological sciences University of Araraquara—UNIARAAraraquara14801-340Brazil Laboratory of Materials(LabMat)and Laboratory of Biopolymers(LaBioPol) Federal Institute of EducationScience and Technology of São Paulo Campus Itapetininga(IFSP)Itapetininga18.202‑000Brazil Instituto Tecnológico de Buenos Aires Cidade Autônoma de Buenos AiresC1437FBCArgentina Conselho Nacional de Pesquisas Científicas e Técnicas(CONICET) Cidade Autônoma de Buenos AiresC1425FQBArgentina Tecnologia YPF(Y-TEC) BerissoBuenos Aires1923Argentina

Polymers from renewable resources have been used for a long time in biomedical applications and found an irreplaceable role in some of *** uses have been increasing because of their attractive properties,contributing to the improvement of life quality,mainly in drug release systems and in regenerative *** using natural polymer,nano and microscale particles preparation,composites,blends and chemical modification strategies have been used to improve their properties for clinical *** many studies have been carried out with these natural polymers,the way to reach the market is long and only very few of them become commercially *** cellulose,bacterial cellulose,chitosan,poly(lactic acid)and starch can be found among the most studied polymers for biological applications,some with several derivatives already established in the market,and others with potential for *** this scenario this work aims to describe the properties and potential of these renewable polymers for biomedical applications,the routes from the bench to the market,and the perspectives for future developments.

关键词： Polymers renewable biomedical applications market

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Inflow and outflow permeability tests in a very soft clay under low stresses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： J.W.s.Vargas F.A.B.Danziger F.R.lopes T.Lunne Federal University of Rio de Janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the BAT probe at sarapuíII soft clay test site are presented.A description of the BAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for sarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test soft clay BAT probe Inflow and outflow tests

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Kentish Plover(Charadrius alexandrinus) and Little Tern(sternula albifrons) prefer shells for nesting:A field experiment

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Avian Research 2024年第1期15卷 55-59页

作者： Macarena castro Andrés De la Cruz Nuria Martin-sanjuan Alejandro Pérez-Hurtado Instituto Universitario de Investigacion Marina(INMAR) Campus de Excelencia Internacional del Mar(CEIMAR)Departamento de BiologíaUniversidad de CadizPuerto RealSpain servicios centrales de Investigacion salinas de la Esperanza Universidad de CadizPuerto RealSpain

shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal ***,supratidal habitats as saltpans could play a role in buffering human *** have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding *** it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they *** this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ *** than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(sternula albifrons) nests were found in patches with shells in both *** best model for both species indicates that the presence of shells is the factor that most correlates with the location of *** probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little *** result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint.

关键词： Habitat management Nest site selection saltpan restoration shell supplementation shorebirds

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Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti sandesh Itani JoséDavid castro sandra Carvalho Ana sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 GPa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%*** testing in simulated body fluid(sBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

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Enhanced Rsa (Ersa): An Advanced Mechanism for Improving the security

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Intelligent Automation & soft Computing 2023年第5期36卷 2267-2279页

作者： s.castro R.PushpaLakshmi Karpagam College of Engineering Coimbatore641032Tamil NaduIndia PsNA College of Engineering And Technology Dindigul624622Tamil NaduIndia

Cloud computing has become ubiquitous in our daily lives in recent *** are the source of technology that is generated hugely by various *** data is dealing with huge data volumes or complex *** major concern in big data is security *** concerns create a negative impact on the user on the aspect of *** big data still,security threats exist as com-monly known as DDOs(Distributed-Denial-of-service)attacks,data loss,Inade-quate Data Backups,system Vulnerabilities,and Phishing as well as social Engineering *** our work,we have taken the data loss and Inadequate Data Backups issues into *** analyze that RsA(Rivest,shamir,&Adleman)is the most secure cryptography *** cloud computing,user authentication is the weaker section to be ***,the cryptogra-phy mechanism is done in the authentication section *** implemented our new idea of registration with selected images and pins for processing *** valid authentication approval earned by the proposed mechanism,the user is allowed to use the cloud database,encryption,decryption,*** prove the efﬁ-ciency level of our proposed system,a comparison work is conducted between DssE(Digital signature standard Encryption)and EFssA(Efﬁcient framework for securely sharing aﬁle using asymmetric key distribution management).The experimental work is carried out and the performance evaluation is done using encryption time and decryption time analysis,throughput,and processing *** this observation,the security level attained by ERsA is far better in compar-ison to DssE and EFssA with the maximum throughput attained by the proposed E-RsA being 500 Mb/Min and encryption time of 3.2 s,thus ensuring the user trust in using the cloud environment.

关键词： Cloud computing encryption decryption ﬁle sharing RsA key generation

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There is more to the knee joint than just the quadriceps:A systematic review with meta-analysis and evidence gap map of hamstring strength,flexibility,and morphology in individuals with gradual-onset knee disorders

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Journal of sport and Health science 2024年第4期13卷 521-536页

作者： Helder s.lopes Marina C.Waiteman Liliam B.Priore Neal R.Glaviano David M.Bazett-Jones Ronaldo V.Briani Fabio M.Azevedo school of science and Technology Physical Therapy DepartmentSao Paulo State University(UNESP)Presidente Prudente 19060-900Brazil Department of Kinesiology College of AgricultureHealth and Natural ResourcesUniversity of ConnecticutStorrsCT 06269USA school of Exercise and Rehabilitation sciences College of Health and Human ServicesUniversity of ToledoToledoOH 43606USA

Background:Impairments in hamstring strength,flexibility,and morphology have been associated with altered knee biomechanics,pain,and *** the presence of these impairments in individuals with gradual-onset knee disorders is important and may indicate targets for assessment and *** systematic review aimed to synthesize the literature to determine the presence of impairments in hamstring strength,flexibility,and morphology in individuals with gradual-onset knee ***:Five databases(MEDLINE,Embase,CINAHL,sPORTDiscus,and Web of science)were searched from inception to september *** studies comparing hamstring outcomes(e.g.,strength,flexibility,and/or morphology)between individuals with gradual-onset knee disorders and their unaffected limbs or pain-free controls were ***-analyses for each knee disorder were ***-level certainty was assessed using the Grading of Recommendations Assessment,Development,and Evaluation,and evidence gap maps were ***:seventy-nine studies across 4 different gradual-onset knee disorders(i.e.,knee osteoarthritis(OA),patellofemoral pain(PFP),chondromalacia patellae,and patellar tendinopathy)were *** with knee OA presented with reduced hamstring strength compared to pain-free controls during isometric(standard mean difference(sMD)=-0.76,95%confidence interval(95%CI):-1.32 to-0.21)and concentric contractions(sMD=-0.97,95%CI:-1.49 to-0.45).Individuals with PFP presented with reduced hamstring strength compared to painfree controls during isometric(sMD=-0.48,95%CI:-0.82 to-0.14),concentric(sMD=-1.07,95%CI:-2.08 to-0.06),and eccentric contractions(sMD=-0.59,95%CI:-0.97 to-0.21).No differences were observed in individuals with patellar *** with PFP presented with reduced hamstring flexibility when compared to pain-free controls(sMD=-0.76,95%CI:-1.15 to-0.36).Evidence gap maps identified insufficient evidence for chondromalacia patel

关键词： Chondromalacia patellae Knee flexors Knee osteoarthritis Patellar tendinopathy Patellofemoral pain

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High-resolution multi-scale air pollution system:Evaluation of modelling performance and emission control strategies

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Journal of Environmental sciences 2024年第3期137卷 65-81页

作者： Diogo lopes Joana Ferreira sandra Rafael Ka In Hoi Xin Li Yuan Liu Ka-Veng Yuen Kai Meng Mok Ana Isabel Miranda Department of Environment and Planning&CEsAM University of AveiroAveiroPortugal Department of Civil&Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoMacao SARChina

A high percentage of the world's population lives in areas where air pollutant concentrations exceed the World Health Organization *** work aims to develop and test,a high-resolution multi-scale air pollution modelling system by integrating a set of adequate *** system is able to provide detailed air pollutant concentrations in urban areas and support air quality management strategies through a better identification of different atmospheric *** also allows furthering the design and assessment of air pollution control measures for a specific *** evaluate its performance and suitability,the system was applied to the Macao special Administrative Region(sAR),China,one of the most densely populated areas on earth,during a winter period when this area is affected by high levels of Particulate Matter(PM).Although the developed system tends to underestimate the PM concentrations,it revealed a good performance in reproducing the temporal and spatial air pollution *** exceedances of the Chinese air quality standards were calculated and high population exposure to PM pollution was *** tested urban atmospheric emission reduction scenarios have shown air quality improvements,indicating that emission reduction measures at urban level should focus on the domestic ***,it is crucial to implement joint pollution prevention strategies with neighbouring regions to improve the air quality in Macao *** approach developed in this work can support policymakers in defining new strategies to reduce atmospheric pollution in urban areas.

关键词： Urban areas High-resolution emission inventory Particulate matter Population exposure

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