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The Algebra of Projective Spheres on Plane, Sphere and Hemisphere

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Journal of Applied Mathematics and Physics 2020年第10期8卷 2286-2333页

作者： István lénárt Eö tvö s loránd University Budapest Hungary

numerous authors studied polarities in incidence structures or algebrization of projective geometry [1] [2]. The purpose of the present work is to establish an algebraic system based on elementary concepts of spherical geometry, extended to hyperbolic and plane geometry. The guiding principle is: “The point and the straight line are one and the same”. Points and straight lines are not treated as dual elements in two separate sets, but identical elements within a single set endowed with a binary operation and appropriate axioms. It consists of three sections. In Section 1 I build an algebraic system based on spherical constructions with two axioms: ab = ba and (ab)(ac) = a, providing finite and infinite models and proving classical theorems that are adapted to the new system. In Section Two I arrange hyperbolic points and straight lines into a model of a projective sphere, show the connection between the spherical napier pentagram and the hyperbolic napier pentagon, and describe new synthetic and trigonometric findings between spherical and hyperbolic geometry. In Section Three I create another model of a projective sphere in the Cartesian coordinate system of the plane, and give methods and techniques for using the model in the theory of functions.

关键词： Projective Spheres Binary Operation Incidence Relation Pappos Desargues Hesse-Chasles Configurations napier Pentagram and Hyperbolic napier Pentagon Polarity in Cartesian Coordinates Differentiable Functions

Synthesis of few layer single crystal graphene grains on platinum by chemical vapour deposition

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Progress in natural Science:Materials International 2015年第4期25卷 291-299页

作者： S.Karamat S.Sonu?en ü.?elik Y.Uysall? E.?zg?nül A.Oral Department of Physics Middle East Technical University COMSATS Institute of Information Technology Faculty of Engineering and natural Sciences Sabanc? University nano Magnetics Instruments ltd.

The present competition of graphene electronics demands an ef fi cient route which produces high quality and large area graphene. Chemical vapour deposition technique, where hydrocarbons dissociate in to active carbon species and form graphene layer on the desired metal catalyst via nucleation is considered as the most suitable method. In this study, single layer graphene with the presence of few layer single crystal graphene grains were grown on Pt foil via chemical vapour deposition. The higher growth temperature changes the surface morphology of the Pt foil so a delicate process of hydrogen bubbling was used to peel off graphene from Pt foil samples with the mechanical support of photoresist and further transferred to Si O2/Si substrates for analysis. Optical microscopy of the graphene transferred samples showed the regions of single layer along with different oriented graphene domains. Two type of interlayer stacking sequences, Bernal and twisted, were observed in the graphene *** presence of different stacking sequences in the graphene layers in fl uence the electronic and optical properties; in Bernal stacking the band gap can be tunable and in twisted stacking the overall sheet resistance can be reduced. Grain boundaries of Pt provides low energy sites to the carbon species, therefore the nucleation of grains are more at the boundaries. The stacking order and the number of layers in grains were seen more clearly with scanning electron microscopy. Raman spectroscopy showed high quality graphene samples due to very small D peak. 2D Raman peak for single layer graphene showed full width half maximum(FWHM) value of 30 cm-1. At points A, B and C, Bernal stacked grain showed FWHM values of 51.22, 58.45 and 64.72 cm-1, while twisted stacked grain showed the FWHM values of 27.26, 28.83 and 20.99 cm-1,respectively. FWHM values of 2D peak of Bernal stacked grain showed an increase of 20–30 cm-1 as compare to single layer graphene which showed its dispersive natu

关键词： Chemical vapour deposition Graphene hexagonal crystals Bernal stacking Twisted stacking Grain boundaries and hydrogen bubbling

new approaches to characterizing urban air particles in central london

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Journal of Environmental Sciences 1999年第3期11卷 367-372页

作者： A.W.Mackay X.long n.l.Rose R.W.Battarbee Environmental Change Research Centre University College London26 Bedford WayLondon.WC1H0APUK

Atmospheric particles in central london during July 1996 have been apportioned to sources by two complimentary techniques: (1) morphological characteristics, determined using high power light microscopy; (2) chemical composition determined by energy dispersive spectroscopy. During the study period, the majority of particles were found to be either biological in origin, or from vehicle related combustion processes. Trends in the latter group of particles are explored further. numbers of particles per cubic metre were determined at an hourly resolution over a period of six days, and were found to be significantly correlated with other traffic pollutants such as benzene and 1,3 butadiene, although there is no relationship with mass of PM10 as measured by a nearby UK Government monitoring station. We suggest in this paper that numbers of particles from car exhausts are more representative of traffic pollution than current estimates which use monitoring by mass.

关键词： urban air pollution particulates london PM10s high power microscopy energy dispersive spectroscopy.

neural activation while perceiving biological motion in dynamic facial expressions and point-light body action animations

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neural Regeneration Research 2010年第14期5卷 1076-1083页

作者： lorna García Pentón Alejandro Pérez Fernández María A.Bobes león Yanely Acosta Ymas lídice Galán García Yasser Iturria-Medina Sandra E.leh Mitchell Valdés-Sosa Cognitive neuroscience laboratory Faculty of PsychologyUniversidad Diego Portales Basque Center on Cognition Brain and language Cognitive Department Cuban Neuroscience Center neuroimaging Department Cuban Neuroscience Center Montreal neurological Institute & Hospital

BACKGROUnD： The interpretation of non-verbal social signals relies heavily on the ability to perceive biological motion. The posterior superior temporal sulcus is an important part of a network involved in biological motion processing. However, the underlying functional organization remains poorly understood. Several studies have suggested topographical representation of motion from different body parts within this region. However, other studies have shown that the posterior superior temporal sulcus responds equally to any body part. OBJECTIVE： Through the use of functional magnetic resonance imaging, the effects of socially relevant biological motion stimuli to activate a specific cortical area within posterior superior temporal sulcus, even if different body parts are involved in motion, will be analyzed. DESIGn, TIME AnD SETTInG： A functional magnetic resonance imaging, block-design was performed at the Magnetic Resonance Imaging, Surgical Medical Investigation Center, Havana, Cuba between 2004 and 2005. PARTICIPAnTS： Thirteen healthy volunteers, from 19 to 55 years of age and compris!ng eight males and five females, were included in the study. METHODS： A conjunction analysis of responses to natural, dynamic, fearful, facial expressions and point-light, body-motion animations. MAIn OUTCOME MEASURES： The corresponding functionally specialized areas, as well as neural areas significant for both types of stimuli, were identified. RESUlTS： One region within the posterior superior temporal sulcus of the right hemisphere was equally activated by facial and body complex motion. COnClUSIOn： A site of common neural activity existed within the posterior superior temporal sulcus, which was not specific to a biological motion type. In addition, the activity was not related to a topographically organized body-part map, which suggested high-level visual representation of biological motion in this region.

关键词： human movement body movement dynamic faces emotional expressions common neural activation overlapped activations

Phase Separation in PCDTBT:PCBM Blends:from Flory-Huggins Interaction Parameters to Ternary Phase Diagrams

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Chinese Journal of Polymer Science 2020年第9期38卷 1025-1033,I0009页

作者： Monika Biernat Pawel Dabczynski Pawel Biernat Jakub Rysz Jagiellonian University Faculty of Physics Astronomy and Applied Computer Science ul.lojasiewicza 1130-348 KrakówPoland Mathematisches Institut Rheinische Friedrich-Wilhelms-Universitat BonnEndenicher Allee 6053115 BonnGermany

The substantial increase in the efficiency of organic solar cells achieved in recent years would not have been possible without work on the synthesis of new materials and understanding the relationship between the morphology and performance of organic photovoltaic *** structure of solvent-cast active layers is a result of phase separation in mixtures of donor and acceptor *** a large extent,this process depends on the interactions between the components of the ***,we present a systematic analysis of the morphology of poly[n-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)](PCDTBT)and[6,6]-phenyl-C71-butyric acid methyl ester(PC70BM)films in terms of the ternary phase *** interaction parameters between PCDTBT and four different solvents,namely chloroform,chlorobenzene,o-dichlorobenzene,and toluene,were estimated based on swelling *** on these values,ternary phase diagrams of PCDTBT:PC70BM in different solvents were *** morphology of spin-coated films with different blend ratios cast from different solvents is discussed in terms of the obtained phase diagrams.

关键词： PCDTBT Ternary phase diagrams Interaction parameter Swelling

Best operating conditions to produce hydroxyapatite nanoparticles by means of a spinning disc reactor

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Frontiers of Chemical Science and Engineering 2014年第2期8卷 156-160页

作者： A. F. D' Intino B. de Caprariis M.l. Santarelli n. Verdone A. Chianese Department of Chemical Engineering Sapienza University via Eudossiana 00184 Rome Italy

In this work, Mg2＋ doped hydroxyapatite （Mg-HAP） nanoparticles were produced by a reactionprecipitation process by using a spinning disc reactor （SDR） at high rotational speed. The production process of these nanoparticles consisted of the neutralization reaction between two aqueous solutions of calcium chloride and ammonia orthophosphate at room temperature. By operating at pH = 10, a high purity Mg-HAP nanoparticles were obtained. In particular, they were 51 nm in average size when the two reagents were fed over the disc symmetrically at 3 cm from the disc center and a rotational speed of the disc reactor equal to 1400 r/min was adopted.

关键词： hydroxyapatite nanoparticles spinning discreactor

Exercise sustains the hallmarks of health

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Journal of Sport and Health Science 2023年第1期12卷 8-35页

作者： Yan Qiu Benjamin Fernández-García H.Immo lehmann Guoping li Guido Kroemer Carlos lópez-Otín Junjie Xiao Institute of Geriatrics(Shanghai University) Affiliated Nantong Hospital of Shanghai University(The Sixth People’s Hospital of Nantong)School of MedicineShanghai UniversityNantong 226011China Cardiac Regeneration and Ageing lab Institute of Cardiovascular SciencesShanghai Engineering Research Center of Organ RepairSchool of Life ScienceShanghai UniversityShanghai 200444China Health Research Institute of the Principality of Asturias(ISPA) Oviedo 33011Spain Department of Morphology and Cell Biology AnatomyUniversity of OviedoOviedo 33006Spain Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School BostonMA 02114USA Centre de Recherche des Cordeliers Equipe labellisee par la Ligue contre le cancerUniversite de Paris CiteSorbonne UniversiteInserm U1138Institut Universitaire de FranceParis 75231France Metabolomics and Cell Biology Platforms Institut Gustave RoussyVillejuif 94805France Institut du Cancer Paris CARPEM Department of BiologyHopital Europeen Georges PompidouAP-HPParis 75015France Departamento de Bioquımica y Biologıa Molecular Facultad de MedicinaInstituto Universitario de OncologıaUniversidad de OviedoOviedo 33006Spain Centro de Investigacion Biomedica en Red Enfermedades Cancer(CIBEROnC) Oviedo 33006Spain

Exercise has long been known for its active role in improving physical fitness and sustaining *** moderate-intensity exercise improves all aspects of human health and is widely accepted as a preventative and therapeutic strategy for various *** is well-documented that exercise maintains and restores homeostasis at the organismal,tissue,cellular,and molecular levels to stimulate positive physiological adaptations that consequently protect against various pathological *** we mainly summarize how moderate-intensity exercise affects the major hallmarks of health,including the integrity of barriers,containment of local perturbations,recycling and turnover,integration of circuitries,rhythmic oscillations,homeostatic resilience,hormetic regulation,as well as repair and ***,we summarize the current understanding of the mechanisms responsible for beneficial adaptations in response to *** review aimed at providing a comprehensive summary of the vital biological mechanisms through which moderate-intensity exercise maintains health and opens a window for its application in other health *** hope that continuing investigation in this field will further increase our understanding of the processes involved in the positive role of moderate-intensity exercise and thus get us closer to the identification of new therapeutics that improve quality of life.

关键词： Beneficial effects of exercise Exercise-related physiological adaptations Hallmarks of health Moderate-intensity exercise Therapeutic exercise

A socioeconomic approach to the profile of microcredit holders from the Hispanic minority in the USA

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Financial Innovation 2023年第1期9卷 484-508页

作者： Salvador Cruz Rambaud Joaquín lópez Pascual Emilio M.Santandreu Departamento de Economía y Empresa Universidad de Almería04120 AlmeríaSpain Departamento de Economía de la Empresa Universidad Rey Juan Carlos28032 VicálvaroMadridSpain OUR Microlending llC MiamiFL 33145USA

The subject of this study is the microcredit market in the USA,more specifically in *** justification for choosing this specific state is the massive presence of the Hispanic *** will facilitate a generalization of the obtained results to the microcredit market in latin American ***,the objective of this study is to analyze the profile of microcredit holders and their companies from socioeconomic and financial points of *** our data also consider the degree of repayment of the microloans included in the sample,the clients’profile is related to the punctuality or default of their corresponding loan repayments using the methodology of multi-nomial logit *** variables used in this study refer to personal information concerning borrowers(gender,age,education level,and marital status),the economic situation of their respective companies(closeness to the lender,number of workers,and revenues),and the characteristics of granted loans(principal,term,and purpose).However,the results of the regression show that only two variables are significant at the 5%significance level:the borrower’s age,which has a positive effect on repay-ment punctuality,and the loan term,which exhibits a negative *** findings of this study have clear implications,as they can help lenders design suitable microloans adjusted to customer ***,future research should include other demograph-ics and characteristics of affected companies.

关键词： Microcredit Customer profile Socioeconomic factors Multinomial logit regression Repayment Microentrepreneurship

Effect of substrate rotation speed on structure and properties of Al-doped ZnO thin films prepared by rf-sputtering

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Transactions of nonferrous Metals Society of China 2017年第9期27卷 2055-2062页

作者： E.A.MARTín-TOVAR l.G.DAZA A.J.R.lóPEZ-ARREGUín A.IRIBARREn R.CASTRO-RODRIGUEZ Departamento de Física Aplicada CINVESTAV-IPNUnidad Mérida Institut Supérieur de l’Aéronautique et de l’Espace (ISAE) Instituto de Ciencia y Tecnología de Materiales (IMRE) Universidad de La Habana

Al-doped ZnO(AZO)thin films were deposited on glass substrates by rf-sputtering at room *** effects of substrate rotation speed(ωS)on the morphological,structural,optical and electrical properties were *** transversal images show that the substrate rotation produces dense columnar structures which were found to be better defined under substrate *** images show that the surface particles of the samples formed under substrate rotation are smaller and denser than those of a stationary one,leading to smaller grain *** results show that all films have hexagonal wurtzite structure and preferred c-axis orientation with a tensile stress along the *** average optical transmittance was above90%in UV-Vis *** lowest resistivity value(8.5×10?3Ω·cm)was achieved atωS=0r/min,with a carrier concentration of1.8×1020cm?3,and a Hall mobility of4.19cm2/(V·s).For all other samples,the substrate rotation induced changes in the carrier concentration and Hall mobility which resulted in the increasing of electrical *** results indicate that the morphology,structure,optical and electrical properties of the AZO thin films are strongly affected by the substrate rotation speed.

关键词： AZO thin film rf-magnetron sputtering microstructure optoelectronic properties substrate rotation speed