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A Symbolic-Numeric Approach for Parametrizing Ruled Surfaces

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journal of Systems Science & Complexity 2020年第3期33卷 799-820页

作者： PÉREZ-dÍAZ sonia SHEN Li-Yong dpto.de Física y Matemáticas Universidad de Alcalá28871-Alcaláde HenaresMadridSpain School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper presents symbolic algorithms to determine whether a given surface(implicitly or parametrically defined)is a rational ruled surface and find a proper parametrization of the ruled ***,in practical applications,one has to deal with numerical objects that are given approximately,probably because they proceed from an exact data that has been perturbed under some previous measuring process or *** these numerical objects,the authors adapt the symbolic algorithms presented by means of the use of numerical *** authors develop numeric algorithms that allow to determine ruled surfaces"close"to an input(not necessarily ruled)surface,and the distance between the input and the output surface is computed.

关键词： Implicit representation numeric algorithm ruled surface standard parametrization

divergent foraging behavior in a hybrid zone： darwin＇s tree finches （Camarhynchus spp.） on Floreana Island

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Current Zoology 2015年第1期61卷 181-190页

作者： Katharina j. PETERS sonia KLEINdORFER School of Biological Sciences Flinders University GPO Box 2100 Adelaide 5001 Australia

Hybrid speciation is increasingly recognized as a mechanism for novel evolutionary trajectories. However, we know very little about the ecology of a contact zone that has arisen in sympatry. This study examines the foraging behavior and fitness of two species of darwin＇s tree finches （Camarhynchus parvulus, C pauper） and hybrid offspring on Floreana Island. Previous study showed that the percentage of hybrids in the tree finch population increased from 19% in 2005 to 41% in 2010, and their body and beak size increased by -5% （parental phenotype did not change）. In 2005-2006, all three tree finch groups （two paren- tal species and hybrid birds） used the same foraging substrate, technique, and height. By 2010-2013, the small tree finch C. par- vulus had changed its foraging technique and the medium tree finch C. pauper had changed its foraging height. Both parental species had higher body condition when foraging at （divergent） mean foraging heights per species but hybrid birds did not. We discuss the implications of conserving forest to facilitate vertical niche expansion and the role of hybridization for genetic persis- tence [Current Zoology 61 （1）： 181-190, 2015].

关键词： Hybridization Speciation Adaptive radiation Conservation Scalesia Ecological niche

On the Base Point Locus of Surface Parametrizations:Formulas and Consequences

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Communications in Mathematics and Statistics 2022年第4期10卷 757-783页

作者： david A.Cox sonia Pérez-díaz j.Rafael Sendra department of Mathematics and Statistics Amherst CollegeAmherstMA 01002USA Universidad de Alcalá Dpto.de Física y Matemáticas28871 MadridSpain

This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate *** a consequence,we get a new proof of the degree formula relating the degree of the surface,the degree of the parametrization,the base point multiplicity and the degree of the rational map induced by the *** addition,we extend both formulas to the case of dominant rational maps of the projective plane and describe how the base point loci of a parametrization and its reparametrizations are *** an application of these results,we explore how the degree of a surface reparametrization is affected by the presence of base points.

关键词： Base point Hilbert-Samuel multiplicity Surface parametrization Reparametrization Parametrization degree Surface degree

Small molecule activators of the p53 response

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journal of Molecular Cell Biology 2019年第3期11卷 245-254页

作者： Marcus j.G.W.Ladds sonia Lain department of Microbiology Tumor and Cell BiologyBiomedicumSolnavagen 9Karolinska Institutet17165StockholmSweden SciLifeLab Tomtebodavagen 23A171 65SoinaStockholmSweden

drugging the p53 pathway has been a goal for both academics and pharmaceutical companies since the designation of p53 as the'guardian of the genome'.Through growing understanding of p53 biology,we can see multiple routes for activation of both wild-type p53 function and restoration of mutant p53?In this review,we focus on small molecules that activate wild-type p53 and that do so in a nongenotoxit *** particular,we will describe potential approaches to targeting proteins that alter p53 stability and function through posttranslational modification,affect p53's subcellular localization,or target RNA synthesis or the synthesis of *** plethora of pathways for exploitation of p53,as well as the wide-ranging response to p53 activation,makes it an attractive target for anti-cancer therapy.

关键词： cancer p53 small molecule cell biology cancer therapy

Effect of Electrolyte Nature on Micellar Soft-Template Electropolymerization in Organic Solvent to Form Nanoporous Polymer Films with a Bioinspired Strategy

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journal of Bionic Engineering 2022年第2期19卷 547-553页

作者： Caroline Fradin Francois Orange sonia Amigoni Frédéric Guittard Thierry darmanin NICE Lab UniversitéCote d’Azur06100 NiceFrance Centre Commun de Microscopie Appliquée(CCMA) UniversitéCote d’Azur06100 NiceFrance

Here,using a bioinspired approach,the soft-template electropolymerization of naphtho[2,3-b]thieno[3,4-e][1,4]dioxine(NaphdOT)was conducted in dichloromethane with different water content,and using different supporting *** role of the electrolytes in the formation of reverse micelles that constitutes the soft template is *** reverse micelles stabilized by the electrolyte and the monomer were observed by TEM and related to the various porous nanostructures of the obtained polymer *** show that the nature of the electrolyte is not only fundamental for the formation of reverse micelles and thus porous nanostructures,but also plays a huge role in the good deposition of the oligomers upon the soft *** with nanostructures such as nanotubes,nanorings or nanomembranes were realized.

关键词： Electropolymerization Soft template Reverse micelles Porous nanostructures

A Survey of the Representations of Rational Ruled Surfaces

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journal of Systems Science & Complexity 2021年第6期34卷 2357-2377页

作者： YUAN Chun-Ming PEREZ-dIAZ sonia SHEN Li-Yong KLMM Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Grupo ASYNACS Dpto.de Fisica y MatematicasUniversidad de Alcala28871-Alcala de HenaresMadridSpain

The rational ruled surface is a typical modeling surface in computer aided geometric design.A rational ruled surface may have different representations with respective advantages and *** this paper,the authors revisit the representations of ruled surfaces including the parametric form,algebraic form,homogenous form and Plucker ***,the transformations between these representations are proposed such as parametrization for an algebraic form,implicitization for a parametric form,proper reparametrization of an improper one and standardized reparametrization for a general *** on these transformation algorithms,one can give a complete interchange graph for the different representations of a rational ruled *** rational surfaces given in algebraic form or parametric form not in the standard form of ruled surfaces,the characterization methods are recalled to identify the ruled surfaces from them.

关键词： Birational transformation characterization implicitization parametrization rational ruled surface reparametrization

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Exploring aramid as emerging contender for CO_2 capture

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Chinese journal of Chemical Engineering 2016年第7期24卷 850-855页

作者： sonia Zulfiqar Muhammad Ilyas Sarwar department of Chemistry School of Natural Sciences (SNS) National University of Sciences and Technology (NUST) department of Chemistry Quaid-i-Azam University

To prevent CO_2 accumulation in the atmosphere generated from scorching of fossil fuels, carbon capture and sequestration(CCS) technology is considered as a potential route to mitigate the emissions of CO_2 from reaching the atmosphere. Power generation from sources such as gas, coal and biomass can fulfill the energy demand more readily than many other sources of electricity production. Thus these sources may be retained as important alternative option in the global energy cycle. In order to curtail CO_2, porous aramid network was fabricated by the condensation of 1,3,5-benzenetricarbonyl trichloride and 1,3-phenylenediamine in 1,4-dioxane solvent. Aramid was characterized for various analyses including FTIR, XRd, TGA, BET surface area and pore size analysis, FESEM and CO_2 adsorption measurements. Excellent thermal stability was provided by strong amide linkages in the polymer backbone. Optimum CO_2 uptake of aramid was achieved to be 23.14 mg·g^(-1) at 273 K at 0.1 MPa. The basic amide groups of network structure showed greater affinity for CO_*** thermal stability of aramid makes it a promising sorbent for CO_2 capture in adverse conditions.

关键词： Greenhouse gasCO2 capturePolymers

Formaldehyde vapour sensing property of electrospun NiO nanograins

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Frontiers of Materials Science 2021年第3期15卷 416-430页

作者： Roopa Kishore KAMPARA sonia T. Balamurugan d. jeyaprakash B.G. Functional Nanomaterials Lab/School of Electrical&Electronics Engineering SASTRA Deemed to be UniversityThanjavurTamil Nadu 613401India

Beads free polyvinyl alcohol(PVA)/NiO nanofibers with an average diameter of 400 nm were successfully prepared through the electrospinning *** nanograins were formed along the axis of the nanofiber due to the calcination of asspun fibers for 24 h at 450℃ and their presence was confirmed by *** nanograins were characterized by XRd,XPS and *** characterization results showed the presence of NiO in nanograins and its polycrystalline nature with ionic *** sensing studies of NiO nanograins were performed towards the pulmonary disease breath markers and they showed better response towards formaldehyde vapour at 350℃.Calcined NiO grains showed a good response towards the 11-1145 ppm of formaldehyde vapour at the operating temperature of 350℃.NiO nanograins also showed quick response time(37 s)and recovery time(14 s)towards 46 ppm of formaldehyde.A sensing mechanism was proposed for the formaldehyde vapour interaction at 350℃ with NiO nanograins.

关键词： electrospinning nanofibers nanograins PVA vapour sensor NiO formaldehyde

Probing the potential of polyester for CO_2 capture

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journal of Environmental Sciences 2014年第7期26卷 1423-1427页

作者： sonia Zulfiqar Muhammad Ilyas Sarwar department of Chemistry School of Natural Sciences (SNS) National University of Sciences and Technology (NUST)Islamabad 44000 Pakistan department of Chemistry Quaid-i-Azam University Islamabad 45320 Pakistan

Global warming, the major environmental issue confronted by humanity today, is caused by rising level of green house gases. Carbon capture and storage technologies offer potential for tapering CO2 emission in the atmosphere. Adsorption is believed to be a promising technology for CO2 capture. For this purpose, a polyester was synthesized by polycondensation of1,3,5-benzenetricarbonyl trichloride and cyanuric acid in pyridine and dichloromethane mixture. The polymer was then characterized using FT-IR, TGA, BET surface area and pore size analysis, FESEM and CO2 adsorption measurements. The CO2 adsorption capacities of the polyester were evaluated at a pressure of 1 bar and two different temperatures（273 and 298 K）.The performance of these materials to adsorb CO2 at atmospheric pressure was measured by optimum CO2 uptake of 0.244 mmol/g at 273 K. The synthesized polyester, therefore, has the potential to be exploited as CO2 adsorbent in pre-combustion capture process.

关键词： PolyesterCO2 captureTGAFESEM