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Journal of Environmental Sciences 2015年第10期27卷 102-111页

作者： Jaqueline Bianchi mario Sérgio Mantovani Maria Aparecida Marin-Morales Department of Biology Institute of BiosciencesSao Paulo State University(UNESP) Department of General Biology Biological Science CentreUniv Estadual de Londrina

Based on the concentration of Malathion used in the field, we evaluated the genotoxic potential of low concentrations of this insecticide on meristematic and F1 cells of Allium cepa and on rat hepatoma tissue culture（HTC cells）. In the A. cepa, chromosomal aberrations（CAs）, micronuclei（MN）, and mitotic index（MI） were evaluated by exposing the cells at 1.5,0.75, 0.37, and 0.18 mg/m L of Malathion for 24 and 48 hr of exposure and 48 hr of recovery time. The results showed that all concentrations were genotoxic to A. cepa cells. However,the analysis of the MI has showed non-relevant effects. Chromosomal bridges were the CA more frequently induced, indicating the clastogenic action of Malathion. After the recovery period, the higher concentrations continued to induce genotoxic effects, unlike the observed for the lowest concentrations tested. In HTC cells, the genotoxicity of Malathion was evaluated by the MN test and the comet assay by exposing the cells at 0.09, 0.009, and0.0009 mg/5 m L culture medium, for 24 hr of exposure. In the comet assay, all the concentrations induced genotoxicity in the HTC cells. In the MN test, no significant induction of MN was observed. The genotoxicity induced by the low concentrations of Malathion presented in this work highlights the importance of studying the effects of low concentrations of this pesticide and demonstrates the efficiency of these two test systems for the detection of genetic damage promoted by Malathion.

关键词： HTC Chromosomal aberration Micronuclei Comet assay Pesticide

Application of flame-formed carbon nanoparticle films for ethanol sensing Author links open overlay panel

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Particuology 2024年第8期91卷 202-210页

作者： Pegah Darvehi Luca Basta mario Commodo Patrizia Minutolo Andrea D'Anna Istituto di Scienze e Tecnologie per l’Energia e la MobilitàSostenibili Consiglio Nazionale delle RicercheP.le Tecchio 8080125NapoliItaly Dipartimento di Ingegneria Chimica dei Materiali e della Produzione IndustrialeUniversitàdegli Studi di Napoli Federico IIP.le Tecchio 8080125NapoliItaly

Carbon nanoparticles(CNPs)have received considerable attention due to their exceptional qualities and *** unique physical and chemical characteristics make them extremely intriguing as materials for numerous high-potential applications,such as electronics and gas *** study focused on producing carbon-based nanomaterial devices by deposition of flame-formed carbon nanoparticles on a suitable substrate and investigating their gas-sensing *** were produced in a fuel-rich laminar premixed ethylene/air flame and the collected CNP film was morphologically and electrically *** electrical conductivity of the film was investigated as a function of ethanol concentration and amount of deposited ***,CNP films exhibited high sensitivity to ambient ethanol gas concentrations,and rapid recovery times at room temperature,and showed a sensitivity increasing with the amount of deposited material and the surface *** findings demonstrate the high potential of combustion-generated CNPs as building materials for low-cost and portable ethanol sensors.

关键词： Flame synthesis Carbon nanoparticles Soot Nanostructured thin film Optical and electrical characterization Atomic force microscopy Sensors

TOWARDS AVOIDING THE HIDDEN TRAPS IN QFD DURING REQUIREMENTS ESTABLISHMENT

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Journal of Systems Science and Systems Engineering 2015年第3期24卷 316-336页

作者： Xinwei Zhang Shurong Tong Hakki Eres Keqin Wang mario Kossmann School of Management Northwestern Polytechnical University Engineering and the Environment University of Southampton Airbus UK AirbusBristol BS99 7ARUK

The Quality Function Deployment （QFD） is a useful and representative methodology to transform customer needs into different level of requirements in a system hierarchy. Simplifications that are based on assumptions are ubiquitous in the QFD, but these underlying assumptions possibly do not hold true, which renders the simplifications unjustified. Additionally, these assumptions are usually not verified within the context of the application domain. This paper identifies and illustrates eight hidden traps in QFD during the process of establishing the requirements, where the assumptions, and therefore, the simplifications made are not reasonable. These traps are implicit in the understanding of customer needs, establishment of system requirements and the flow down of these requirements to lower levels of the system hierarchy. Suggestions are given to help avoiding these hidden traps, thereby eliminating or alleviating their potentially detrimental effects. The intent of the paper is to make readers aware of these traps when applying QFD for the establishment of requirements, so that they may utilize QFD with a better understanding of its limitations and develop higher quality specifications.

关键词： QFD requirements establishment value decision-making

Self-assembly of highly ordered DNA origami lattices at solid-liquid interfaces by controlling cation binding and exchange

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Nano Research 2020年第11期13卷 3142-3150页

作者： Yang Xin Salvador Martinez Rivadeneira Guido Grundmeier mario Castro Adrian Keller Technical and Macromolecular Chemistry Paderborn UniversityPaderborn33098Germany Grupo Interdisciplinar de Sistemas Complejos and Instituto de Investigación Tecnológica Universidad Pontificia Comillas de MadridMadrid28015Spain

The surface-assisted hierarchical self-assembly of DNA origami lattices represents a versatile and straightforward method for the organization of functional nanoscale objects such as proteins and ***,we demonstrate that controlling the binding and exchange of different monovalent and divalent cation species at the DNA-mica interface enables the self-assembly of highly ordered DNA origami lattices on mica *** development of lattice quality and order is quantified by a detailed topological analysis of high-speed atomic force microscopy(HS-AFM)*** find that lattice formation and quality strongly depend on the monovalent cation ***^(+)is more effective than Li^(+)and K^(+)in facilitating the assembly of high-quality DNA origami lattices,because it is replacing the divalent cations at their binding sites in the DNA backbone more *** regard to divalent cations,Ca^(2+)can be displaced more easily from the backbone phosphates than Mg^(2+)and is thus superior in guiding lattice *** independently adjusting incubation time,DNA origami concentration,and cation species,we thus obtain a highly ordered DNA origami lattice with an unprecedented normalized correlation length of *** the correlation length,we use computer vision algorithms to compute the time course of different topological observables that,overall,demonstrate that replacing MgCl_(2) by CaCl_(2) enables the synthesis of DNA origami lattices with drastically increased lattice order.

关键词： DNA origami self-assembly lattice formation high-speed atomic force microscopy topological analysis

Mathematical operations and equation solving with reconfigurable metadevices

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Light(Science & Applications) 2022年第10期11卷 2365-2377页

作者： Dimitrios C.Tzarouchis mario Junior Mencagli Brian Edwards Nader Engheta University of Pennsylvania Department of Electrical and Systems EngineeringPhiladelphiaPA 19104USA University of North Carolina at Charlotte Department of Electrical and Computer EngineeringCharlotteNC 28223USA

Performing analog computations with metastructures is an emerging wave-based paradigm for solving mathematical *** such devices,one major challenge is their reconfigurability,especially without the need for a priori mathematical computations or computationally-intensive *** equation-solving capabilities are applied only to matrices with special spectral(eigenvalue)*** we report the theory and design of wave-based metastructures using tunable elements capable of solving integral/differential equations in a fully-reconfigurable *** consider two architectures:the Miller architecture,which requires the singular-value decomposition,and an alternative intuitive direct-complex-matrix(DCM)architecture introduced here,which does not require a priori mathematical *** examples,we demonstrate,using system-level simulation tools,the solutions of integral and differential *** then expand the matrix inverting capabilities of both architectures toward evaluating the generalized Moore-Penrose matrix ***,we provide evidence that metadevices can implement generalized matrix inversions and act as the basis for the gradient descent method for solutions to a wide variety of ***,a general upper bound of the solution convergence time reveals the rich potential that such metadevices can offer for stationary iterative schemes.

关键词： equation operations Mathematical

Tree-inspired dendriforms and fractal-like branching structures in architecture： A brief historical overview

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Frontiers of Architectural Research 2014年第3期3卷 298-323页

作者： Iasef Md Rian mario Sassone Department of Architecture and Design (DAD) Politecnico di Torino Viale Pier Andrea Ivlattioli - 39Turin 10125 Italy

The shapes of trees are complex and fractal-like, and they have a set of physical, mechanical and biological functions. The relation between them always draws attention of human beings throughout history and, focusing on the relation between shape and structural strength, architects have designed a number of treelike structures, referred as dendriforms. The replication and adoption of the treelike patterns for constructing architectural structures have been varied in different time periods based on the existing and advanced knowledge and available technologies. This paper, by briefly discussing the biological functions and the mechanical properties of trees with regard to their shapes, overviews and investigates the chronological evolution and advancements of dendriform and arboreal structures in architec- ture referring to some important historical as well as contemporary examples.

关键词： Architecture Tree Dendriforms Fractal geometry Branching structures Technology

Random noise stimulation in the treatment of patients with neurological disorders

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Neural Regeneration Research 2022年第12期17卷 2557-2562页

作者： Mateo A.Herrera-Murillo mario Treviño Elias Manjarrez Facultad de Medicina Plan de Estudios Combinados en Medicina(PECEM)UNAMCircuito InteriorCiudad UniversitariaAv.UniversidadCiudad de MéxicoMéxico Instituto de Neurociencias Universidad de GuadalajaraGuadalajaraJaliscoMéxico Instituto de Fisiología Benemérita Universidad Autónoma de PueblaPueblaMéxico

Random noise stimulation technique involves applying any form of energy(for instance,light,mechanical,electrical,sound)with unpredictable intensities through time to the brain or sensory receptors to enhance sensory,motor,or cognitive *** noise stimulation initially employed mechanical noise in auditory and cutaneous stimuli,but electrical energies applied to the brain or the skin are becoming more frequent,with a series of clinical ***,recent evidence shows that transcranial random noise stimulation can increase corticospinal excitability,improve cognitive/motor performance,and produce beneficial aftereffects at the behavioral and psychological ***,we present a narrative review about the potential uses of random noise stimulation to treat neurological disorders,including attention deficit hyperactivity disorder,schizophrenia,amblyopia,myopia,tinnitus,multiple sclerosis,post-stroke,vestibular-postural disorders,and sensitivity *** of the reviewed studies reveal that the optimal way to deliver random noise stimulation-based therapies is with the concomitant use of neurological and neuropsychological assessments to validate the beneficial *** addition,we highlight the requirement of more randomized controlled trials and more physiological studies of random noise stimulation to discover another optimal way to perform the random noise stimulation interventions.

关键词： auditory noise mechanical noise neurological disorders neuronal noise noise galvanic vestibular stimulation non-invasive brain stimulation transcranial electrical stimulation transcranial random noise stimulation

Forecasting technical debt evolution in software systems:an empirical study

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Frontiers of Computer Science 2023年第3期17卷 63-75页

作者： Lerina AVERSANO mario Luca BERNARDI Marta CIMITILE Martina IAMMARINO Debora MONTANO Department of Engineering University of SannioBenevento 82100Italy Department of Law and Economics Unitelma Sapienza University of RomeRome 00161Italy

Technical debt is considered detrimental to the long-term success of software development,but despite the numerous studies in the literature,there are still many aspects that need to be investigated for a better understanding of *** particular,the main problems that hinder its complete understanding are the absence of a clear definition and a model for its identification,management,and *** on forecasting technical debt,there is a growing notion that preventing technical debt build-up allows you to identify and address the riskiest debt items for the project before they can permanently compromise ***,despite this high relevance,the forecast of technical debt is still little *** this end,this study aims to evaluate whether the quality metrics of a software system can be useful for the correct prediction of the technical ***,the data related to the quality metrics of 8 different open-source software systems were analyzed and supplied as input to multiple machine learning algorithms to perform the prediction of the technical *** addition,several partitions of the initial dataset were evaluated to assess whether prediction performance could be improved by performing a data *** results obtained show good forecasting performance and the proposed document provides a useful approach to understanding the overall phenomenon of technical debt for practical purposes.

关键词： technical debt empirical study software quality metrics machine learning

Scale-Free Percolation in Continuum Space

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Communications in Mathematics and Statistics 2019年第3期7卷 269-308页

作者： Philippe Deprez mario V.Wüthrich RiskLab Department of MathematicsETH Zurich8092 ZurichSwitzerland

The study of real-life network modeling has become very popular in recent *** attractive model is the scale-free percolation model on the lattice Zd,d≥1,because it fulfills several stylized facts observed in large real-life *** adopt this model to continuum space which leads to a heterogeneous random-connection model on Rd:Particles are generated by a homogeneous marked Poisson point process on Rd,and the probability of an edge between two particles is determined by their marks and their *** this model we study several properties such as the degree distributions,percolation properties and graph distances.

关键词： Scale-free percolation Continuum percolation Random-connection model Degree distribution Phase transition Graph distance

Ops!... Where is my left main？

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Journal of Geriatric Cardiology 2018年第9期15卷 609-610页

作者： Gianluca Rigatelli mario Lupia Marco Zuin Cardiovascular Diagnosis and Endoluminal hlterventions Unit Rovigo General Hospital Rovigo Italy Vascular Surgery Padua University School of Medicine. Padua Italy Section of Internal and Cardiopuhnonary Medicine Department of Medical Science University of Ferrara Ferrara Italy

Coronary artery anomalies can reach easily nowadays elderly age, causing troubles at both diagnostic and thera- peutic levels. A 80-year-old hypertensive man underwent coronary artery angiography because of a doubtful... 详细信息

关键词： Angiography Left main Right coronary artery