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Synthesis of 1,2-Diphenyliminoethanols and the Evaluation of Their Possible Biological Activity

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Journal of Chemistry and Chemical Engineering 2020年第1期14卷 11-15页

作者： Portillo Borgues Jorge Eduardo santos santos elvira Lejarazo Gómez Eva Florencia Department of Organic Chemistry Faculty of ChemistryPostgraduate Studies UnitsCircuito Exterior S/NCiudad UniversitariaCP 04510CoyoacánMexico CityMexico

The chemical cellular signaling pathway of phosphatidylinositol-3-kinase(PI3K)is crucial in many aspects of cell growth and *** alterations such as amplification,mutation and chromosomal transposition can compromise the PI3K pathway,leading to its permanent activation,which results in the alteration of growth control and cell survival mechanisms,favoring competitive growth,metastatic capacity,and often a greater resistance to *** of these destructive genetic modifications has been found in different types of ***,a group of researchers found that the structure of benzoin matches the fingerprint of the active PI3K *** focus of this work is on the synthesis of substituted benzoins via benzoin condensation in aqueous medium for subsequent reaction with *** aim is to obtain a series of new compounds derived from 1,2-diphenyliminoethanol,which will be sent to a specialized laboratory to evaluate their cytotoxicity on carcinoma cell lines.

关键词： Benzoin Schiff bases 1 2-diphenyliminoethanol

Cooperative Hypermedia Editing with CoMEdiA

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Journal of Computer Science & Technology 1993年第3期8卷 257-269页

作者： Adelino santos Fraunhofer

CoMEdiA is a groupware tool which enables co-authors to cooperatively produce hypermedia docu- *** allows co-authors to communicate their ideas,drafts,guidelines,constraints and annota- tions to other *** uses a mix of communication patterns,media and document organization to enable co-authors to keep on exchanging information(remotely or face-to-face),improving passages and modifying notes until a final document is *** did not concentrate on the depth but on the breath of the *** efforts were on integrating and coordinating concepts from collaboration, multimedia and hyper organization rather than on making a specialized system in any of *** be- gan with the text medium and are now including bitmaps and raster *** sound and video will also be *** this paper we describe and sustain the available capacities.

关键词： Cooperative editing groupware hypermedia multi-user interfaces multimedia

Performance Comparison of Field-oriented Control,Direct Torque Control,and Model-predictive Control for SynRMs

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Chinese Journal of Electrical Engineering 2022年第1期8卷 24-37页

作者： Hazem Hadla Fernando santos Polytechnic Institute of Viseu Higher School of Technology and Management of LamegoLamego 5100-074Portugal

Simulation studies of three synchronous reluctance motor(SynRM)control strategies are presented:field-oriented control(FOC),direct torque control(DTC),and finite-set model-predictive control(FS-MPC).FOC uses linear controllers and pulse-width modulation to control the fundamental components of the load voltages *** contrast,DTC and FS-MPC are nonlinear strategies wherein the voltage vectors are directly generated in the absence of a *** operating principles and control structures of these control strategies are ***,a comparative analysis of the static and dynamic performance of the control strategies is conducted using Matlab/Simulink to identify their advantages and *** is confirmed that each of the control strategies has merits and that all three of them satisfy the requirements of modern high-performance drives.

关键词： Field-oriented control direct torque control model-predictive control synchronous reluctance motor

The effect of drying of Piper hispidinervium bydifferent methods and its influence on the yield ofessential oil and safrole

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Information Processing in Agriculture 2023年第1期10卷 28-39页

作者： Helder Kiyoshi Miyagawa Alberdan Silva santos Systematic Investigation in Biotechnology and Molecular Biodiversity Laboratory Federal University of Para´Bele´m 66075-110PABrazil

The Piper hispidinervium leaves and thin stems were dried under laboratory and field *** drying was performed using a shade dryer operating with and without forced convection and an oven dryer operating at 30 and 40*** experiments were conducted using solar dryers with three different covers,i.e.,transparent,black plastic,and palm straw *** essential oil extraction was performed by steam distillation,and the safrole content was analyzed by gas *** mathematical models(Page,logarithmic,Henderson and Pabis,fractional,and diffusion)were fitted with the experimental data and compared based on the coefficient of determination(R2),root mean square error(RMSE)and *** suggest that the best model was the logarithmic model(R2>0.99,RMSE<0.0005,and v2<0.005).With sufficient drying,the safrole content increased up to 95%of the extracted oil;however,when the drying time was prolonged,both the oil yield and safrole content of the extracted oil decreased.

关键词： Modeling Drying kinetics Essential oil extraction Safrole extraction Piperaceae

Systematic oil flow modeling in the Quasi-3D approximation yields additional terms that allows for variable cross-section area tubing

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Petroleum 2021年第1期7卷 53-63页

作者： Edval J.P.santos Laboratory for Devices and Nanostructures Engineering at the Nanometer Scale GroupUniversidade Federal de Pernambuco-UFPERecifeBrazil

A systematic model development for oil flow in quasi-3D(1Dþ2D)is *** approach provides a unified modeling ***,additional terms are obtained,which allows for tubing area variation along the flow *** area variation can be modeled as analytic function or random fluctuation,as it could be the result of deposits or tubing internal surface *** proposed approach can be used to obtain analytic solutions which provide physical insight into the phenomena under scrutiny,including the validation of software tools,sensor development and sensor *** starts from conservation laws as given by kinetic theory and applies the transverse averaging technique(TAT)to extract the one-dimensional approximation in formal *** demonstrate its application,the steady-state Ramey’s model,the Hasan’s transient model and a simple two-phase model are generated from the obtained equations.

关键词： Conservation equation Flow model Two-phase flow Ramey’s model Hasan’s model

Modeling neutral-atmospheric electromagnetic delays in a“big data”world

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Geo-Spatial Information Science 2018年第2期21卷 75-79页

作者： Marcelo C.santos Thalia Nikolaidou Department of Geodesy and Geomatics Engineering University of New BrunswickFrederictonCanada

If left unmodeled,the delay suffered by electromagnetic waves while crossing the neutral atmosphere negatively affects Global Navigation Satellite System *** modeling of the delay has been carried out by means of empirical models formulated based on climatological information or using information extracted from numerical weather prediction(NWP)*** paper explores the potential use of meteorological information of several types that will become available with the increasing number of sensors(e.g.a cell phone,or the thermometer of a nearby smart home)in *** can we make use of these potentially huge datasets,which may help to provide the best possible representation of the neutral atmosphere at any given time,as readily and as accurately as possible?This situation falls in the realm of Big Data.A few potential scenarios,a sequential improvement of Marini mapping function coefficients,a self-feeding NWP,and near real-time empirical model updates,are discussed in this *** pros and cons of each approach are discussed in comparison with what is done *** indicate that they have potential for a positive contribution.

关键词： Global navigation satellite system(GNSS) big data neutral atmosphere

Use of improved cold-finger technique to assess effects of basicity on heat transfer through solidified mold flux

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Journal of Iron and Steel Research International 2019年第4期26卷 393-402页

作者： Karina Lara santos Assis Petrus Christiaan Pistorius Department of Materials Science and Engineering Center for Iron and Steelmaking ResearchCarnegie Mellon UniversityPittsburgh 15213PAUSA

Cold-finger measurements were used to estimate the contact resistance and average thermal conductivity of mold flux films solidified on a water-cooled copper *** industrial mold fluxes,with basicities from low to high,were *** steady-state rate of convective heat transfer between the solid film and liquid flux was compared with calculations based on natural convection correlations;the comparison indicates that the surface of the solid film(in contact with molten flux)is approximately at its solidus *** roughness of the mold flux film in contact with copper was larger for films grown from higher-temperature mold flux and for higher-basicity mold *** glassy(low-basicity)film had an estimated thermal conductivity of 1.1 W/(m K).The crystalline or partially crystalline films had higher estimated thermal conductivities of 2.2-3.2 W/(m K).The measured values of thermal resistance were extrapolated to typical mold flux film thicknesses for industrial conditions;the extrapolations confirmed that the high contact resistance of higher-basicity mold fluxes can yield higher thermal resistances than the low-basicity *** morphology of the rough interface of higherbasicity mold flux films that gives the higher contact resistance is consistent with that observed in previous work and appears not to be directly related to crystallization.

关键词： Mold flux Heat transfer Conduction Contact resistance-Cold-finger technique

Animals as sources of food-borne pathogens: A review

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Animal Nutrition 2018年第3期4卷 250-255页

作者： Norma Heredia santos García Departamento de Microbiología e Inmunología Facultad de Ciencias Biolóogicas Universidad Autóonoma de Nuevo Leóon Apdo.Postal 124-F Ciudad Universitaria San Nicolóas de los Garza

Food-producing animals are the major reservoirs for many foodborne pathogens such as Campylobacter species, non-Typhi serotypes of Salmonella enterica, Shiga toxin-producing strains of Escherichia coli, and Listeria monocytogenes. The zoonotic potential of foodborne pathogens and their ability to produce toxins causing diseases or even death are sufficient to recognize the seriousness of the situation. This manuscript reviews the evidence that links animals as vehicles of the foodborne pathogens Salmonella,Campylobacter, Shiga toxigenic E. coli, and L. monocytogenes, their impact, and their current status. We conclude that these pathogenic bacteria will continue causing outbreaks and deaths throughout the world, because no effective interventions have eliminated them from animals and food.

关键词： Animal food Foodborne pathogens Zoonosis Enteropathogens Pathogenic bacteriara

Exact Computation of the Topology and Geometric Invariants of the Voronoi Diagram of Spheres in 3D

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Journal of Computer Science & Technology 2013年第2期28卷 255-266页

作者： Franois Anton Darka Mioc Marcelo santos Research Division of Geodesy National Space Institute Technical University of Denmark Department of Geodesy and Geomatics Engineering University of New Brunswick

In this paper, we are addressing the exact the Voronoi diagram of spheres using Wu＇s algorithm. computation of the Delaunay graph （or quasi-triangulation） and Our main contributions are first a methodology for automated derivation of invariants of the Delaunay empty circumsphere predicate for spheres and the Voronoi vertex of four spheres, then the application of this methodology to get all geometrical invariants that intervene in this problem and the exact computation of the Delaunay graph and the Voronoi diagram of spheres. To the best of our knowledge, there does not exist a comprehensive treatment of the exact computation with geometrical invariants of the Delaunay graph and the Voronoi diagram of spheres. Starting from the system of equations defining the zero-dimensional algebraic set of the problem, we are applying Wu＇s algorithm to transform the initial system into an equivalent Wu characteristic （triangular） set. In the corresponding system of algebraic equations, in each polynomial （except the first one）, the variable with higher order from the preceding polynomial has been eliminated （by pseudo-remainder computations） and the last polynomial we obtain is a polynomial of a single variable. By regrouping all the formal coefficients for each monomial in each polynomial, we get polynomials that are invariants for the given problem. We rewrite the original system by replacing the invariant polynomials by new formal coefficients. We repeat the process until all the algebraic relationships （syzygies） between the invariants have been found by applying Wu＇s algorithm on the invariants. Finally, we present an incremental algorithm for the construction of Voronoi diagrams and Delaunay graphs of spheres in 3D and its application to Geodesy.

关键词： Voronoi diagram of spheres Delaunay graph of spheres Wu's method invariant characteristic set