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Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

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Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling Si Hongli Li david Da Yong Chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan Zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment *** effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of *** affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were *** optimum conditions were found to be 120℃,10 min,and 3 cycles,***-MS/MS method was developed to obtain the optimal sensitivity specific to *** method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/*** ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent *** optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target ***,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to *** is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

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A combined experimental and DEM investigation of grain interlocking in sheared granular assemblies

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Particuology 2024年第7期90卷 436-451页

作者： rui Lu Qiang Luo Tengfei Wang david P.Connolly Tao Xie School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-Speed railway Engineering(Southwest Jiaotong University) Ministry of EducationChengdu 610031China School of Civil Engineering University of LeedsLeeds LS29JTUK Department of Civil Engineering McMaster UniversityHamiltonONCanada

Compacted granular material,integral to geotechnical engineering,undergoes translation,rotation,and interlocking when subject to shear displacements or external *** present study focuses on the interlocking of heterogeneous granular materials,a complex behavior influenced by gradation,compaction,and varying particle geometry,and has consequently received limited attention in existing *** address this research gap,we conducted an analysis on the effect of grain interlocking on the shear resistance of granular assemblies,using a combination of laboratory testing and the discrete element method(DEM).Initially,large-scale direct shear tests were conducted on gravel−sand mixes with varying degrees of compaction and normal *** of the mixes also underwent subsequent shear reversal to explore the differences in grain interlocking between the two shearing processes on the shear *** analyzing the laboratory results,a mesoscopic scale investigation was performed by replicating the test using discrete element *** facilitate this,granular particle geometries were measured using 3D laser scanning based on the physical lab ***,based on these scans,discrete element r-block and ball models were utilized to construct both the coarse and fine particles within the *** vibro-compaction was employed to regulate the degree of *** results indicate that an increase in vertical pressure,coupled with a zero dilatancy angle,results in a rising stress ratio,indicative of grain *** interlocking exhibits a positive correlation with both the coarse content and the degree of compaction,and varies depending on the shear *** interlocking progresses,the shear band,induced by particle movement,expands and is associated with reduced particle rotation near the shear *** study further reveals a consistent positive correlation between interlocking and the principal orientation angle of strong normal c

关键词： Granular material Interlocking Shear resistance Direct shear Discrete element method Vibro-compaction

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Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： Eric r.Hoglund Andrew r.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations

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Severe acute respiratory syndrome coronavirus-2-related and imputable deaths in children:results from the French pediatric national registry

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World Journal of Pediatrics 2024年第6期20卷 611-620页

作者： Marguerite Lockhart-Bouron Noemie Vanel Michael Levy Anais r.Briant Etienne Javouhey Sophie Breinig Julia Dina Marion Caseris Francois Angoulvant Stephane Leteurtre Morgan recher david W.Brossier Univ.Lille CHU LilleULR 2694-METRICS:Evaluation Des Technologies de Sante Et Des Pratiques Medicales59000LilleFrance Pediatric Intensive Care Unit CHU de MarseilleMarseilleFrance Pediatric Intensive Care Unit CHU Robert-DebreAssistance Publique Hopitaux de ParisParisFrance UniversitéParis-Cite ParisFrance Biostatistics and Clinical research Unit CHU de Caen Normandie14000CaenFrance Pediatric Intensive Care Hospices Civils de LyonLyonFrance Neonatal andPediatric IntensiveCare Unit Children's HospitalToulouseFrance Virology Department INSERM U1311 DynamicureUniv CAEN NormandieCHU de Caen14000 CaenFrance Medical School Universite Caen Normandie14000 CaenFrance Department of Pediatrics CHU Robert-DebréAssistance Publique Hopitaux de ParisParisFrance Department Women-Mother-Child Service of PediatricsLausanne University Hospital(CHUV)LausanneSwitzerland Pediatric Intensive Care Unit Réanimation Et Soins Intensifs PéediatriquesCHU de CAENAvenue de La Cote de Nacre14000 CaenFrance CHU Sainte Justine research Center MontréalCanada

Background Severe acute respiratory syndrome coronavirus-2(SArS-CoV-2)is responsible for an important mortality rate *** aimed to evaluate the actual imputability of SArS-CoV-2 on the mortality rate associated with SArS-CoV-2-related illnesses in the pediatric intensive care unit(PICU).Secondary objectives were to identify risk factors for *** This national multicenter comparative study comprised all patients under 18 years old with positive SArS-CoV-2 polymerase chain reactions(PCrs)[acute corona virus disease 2019(COVID-19)or incidental SArS-CoV-2 infection]and/or pediatric inflammatory multisystem syndrome(PIMS)recorded in the French PICU registry(PICUre)between September 1,2021,and August 31,*** patients were classified and compared according to their living status at the end of their PICU *** patients were evaluated by four experts in the field of pediatric infectiology and/or pediatric intensive *** imputability of SArS-CoV-2 as the cause of death was classified into four categories:certain,very probable,possible,or unlikely,and was defined by any of the first three *** There were 948 patients included of which 43 died(4.5%).From this,26 deaths(67%)could be attributed to SArS-CoV-2 infection,with an overall mortality rate of 2.8%.The imputability of death to SArS-CoV-2 was considered certain in only one case(O.1%).Deceased patients suffered more often from comorbidities,especially heart disease,neurological disorders,hematological disease,cancer,and *** of the deceased patients were admitted for pediatric inflam-matory multisystem syndrome(PIMS).Mortality risk factors were male gender,cardiac comorbidities,cancer,and acute respiratorydistress *** SArS-CoV-2 mortality in the French pediatric population was *** though the imputability of SArS-Cov-2 on mortality was considered in almost two-thirds of cases,this imputability was considered certain in only one case.

关键词： Death Pediatric intensive care unit SArS-CoV-2

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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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Navigating the controversy regarding antibiotic prophylaxis in acute variceal bleeding

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World Journal of Gastroenterology 2024年第18期30卷 2485-2487页

作者： david Aguirre-Villarreal Ignacio García-Juárez Department of Gastroenterology and Liver Transplant Unit Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

Antibiotic prophylaxis in patients with cirrhosis and acute variceal bleeding is part of the standard of care according to most clinical ***,with recent evidence arguing against antibiotic prophylaxis,the role of this... 详细信息

关键词： Cirrhosis Acute variceal bleeding Antibiotic prophylaxis Endoscopic band ligation Spontaneous bacterial peritonitis

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Current state of the art and future directions: Augmented reality data visualization to support decision-making

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Visual Informatics 2024年第2期8卷 80-105页

作者： Mengya Zheng david Lillis Abraham G.Campbell School of Computer Science University College DublinDublinIreland

Augmented reality(Ar),as a novel data visualization tool,is advantageous in revealing spatial data patterns and data-context ***,recent research has identified Ar data visualization as a promising approach to increasing decision-making efficiency and *** a result,Ar has been applied in various decision support systems to enhance knowledge conveying and comprehension,in which the different data-reality associations have been constructed to aid ***,how these Ar visualization strategies can enhance different decision support datasets has not been reviewed *** given the rise of big data in the modern world,this support is critical to decision-making in the coming *** Ar to embed the decision support data and explanation data into the end user’s physical surroundings and focal contexts avoids isolating the human decision-maker from the relevant *** the decision-maker’s contexts and the DSS support in Ar is a difficult *** paper outlines the current state of the art through a literature review in allowing Ar data visualization to support *** facilitate the publication classification and analysis,the paper proposes one taxonomy to classify different Ar data visualization based on the semantic associations between the Ar data and physical *** on this taxonomy and a decision support system taxonomy,37 publications have been classified and analyzed from multiple *** of the contributions of this literature review is a resulting Ar visualization taxonomy that can be applied to decision support *** with this novel tool,the paper discusses the current state of the art in this field and indicates possible future challenges and directions that Ar data visualization will bring to support decision-making.

关键词： Augmented reality Decision support Data visualization Taxonomy

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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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Task Offloading in Edge Computing Using GNNs and DQN

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2649-2671页

作者： Asier Garmendia-Orbegozo Jose david Nunez-Gonzalez Miguel Angel Anton Department of Applied Mathematics University of the Basque Country UPV/EHUEibar20600Spain TECNALIA Basque Research and Technology Alliance(BRTA)San Sebastian20009Spain

In a network environment composed of different types of computing centers that can be divided into different layers(clod,edge layer,and others),the interconnection between them offers the possibility of peer-to-peer task *** many resource-constrained devices,the computation of many types of tasks is not feasible because they cannot support such computations as they do not have enough available memory and processing *** this scenario,it is worth considering transferring these tasks to resource-rich platforms,such as Edge Data Centers or remote cloud *** different reasons,it is more exciting and appropriate to download various tasks to specific download destinations depending on the properties and state of the environment and the nature of the *** the same time,establishing an optimal offloading policy,which ensures that all tasks are executed within the required latency and avoids excessive workload on specific computing centers is not *** study presents two alternatives to solve the offloading decision paradigm by introducing two well-known algorithms,Graph Neural Networks(GNN)and Deep Q-Network(DQN).It applies the alternatives on a well-known Edge Computing simulator called PureEdgeSimand compares them with the two defaultmethods,Trade-Off and round *** showed that variants offer a slight improvement in task success rate and workload *** terms of energy efficiency,they provided similar ***,the success rates of different computing centers are tested,and the lack of capacity of remote cloud servers to respond to applications in real-time is *** novel ways of finding a download strategy in a local networking environment are unique as they emulate the state and structure of the environment innovatively,considering the quality of its connections and constant *** download score defined in this research is a crucial feature for determining the quality of a download path

关键词： Edge computing edge offloading fog computing task offloading

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Geometric prior guided hybrid deep neural network for facial beauty analysis

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 467-480页

作者： Tianhao Peng Mu Li Fangmei Chen Yong Xu david Zhang The School of Computer Science and Technology Guizhou UniversityGuiyangChina Department of Automation Moutai InstituteRenhuaiGuizhouChina The School of Computer Science and Technology Harbin Institute of TechnologyShenzhenShenzhenChina The Information and Communication Engineering Department Dalian Minzu UniversityDalianChina The School of Data Science The Chinese University of Hong KongShenzhenShenzhenChina

Facial beauty analysis is an important topic in human *** may be used as a guidance for face beautification applications such as cosmetic *** neural networks(DNNs)have recently been adopted for facial beauty analysis and have achieved remarkable ***,most existing DNN-based models regard facial beauty analysis as a normal classification *** ignore important prior knowledge in traditional machine learning models which illustrate the significant contribution of the geometric features in facial beauty *** be specific,landmarks of the whole face and facial organs are introduced to extract geometric features to make the *** by this,we introduce a novel dual-branch network for facial beauty analysis:one branch takes the Swin Transformer as the backbone to model the full face and global patterns,and another branch focuses on the masked facial organs with the residual network to model the local patterns of certain facial ***,the designed multi-scale feature fusion module can further facilitate our network to learn complementary semantic information between the two *** model optimisation,we propose a hybrid loss function,where especially geometric regulation is introduced by regressing the facial landmarks and it can force the extracted features to convey facial geometric *** performed on the SCUT-FBP5500 dataset and the SCUT-FBP dataset demonstrate that our model outperforms the state-of-the-art convolutional neural networks models,which proves the effectiveness of the proposed geometric regularisation and dual-branch structure with the hybrid *** the best of our knowledge,this is the first study to introduce a Vision Transformer into the facial beauty analysis task.

关键词： deep neural networks face analysis face biometrics image analysis

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