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Quantization of Newton’s Gravity

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Journal of Modern Physics 2020年第6期11卷 920-927页

作者： Mario C. Rocca Angelo Plastino departamento de Física Universidad Nacional de La Plata La Plata Argentina departamento de matemática Universidad Nacional de La Plata La Plata Argentina Consejo Nacional de Investigaciones Científicas y Tecnológicas (IFLP-CCT-CONICET) La Plata Argentina SThAR-EPFL Lausanne Switzerland

In this work we will use a recently developed non relativistic (NR) quantization methodology that successfully overcomes troubles with infinities that plague non-renormalizable quantum field theories (QFTs). The ensuing methodology is here applied to Newton’s gravitation potential. We employ here the concomitant mathematical apparatus to formulate the NR QFT discussed in the well known classical text-book by Fetter and Walecka. We emphasize the fact that we speak of non relativistic QFT. This is so because we appeal to Newton’s gravitational potential, while in a relativistic QFT one does not employ potentials. Our main protagonist is the notion of propagator. This notion is of the essence in non relativistic quantum field theory (NR-QFT). Indeed, propagators are indispensable tools for both nuclear physics and condensed matter theory, among other disciplines. In the present work we deal with propagators for both fermions and bosons.

关键词： Non-Relativistic Quantum Field Theory Newton’s Gravity Schwartz’ Distributions

Modelling Animal Activity as Curves: An Approach Using Wavelet-Based Functional Data Analysis

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Open Journal of Statistics 2017年第2期7卷 203-215页

作者： Barbara Henning Airton Kist Alusio Pinheiro Rafael L. Camargo Thiago M. Batista Everardo M. Carneiro Sérgio F. dos Reis Programa de Pós-graduaç &atilde o em Ecologia Universidade Estadual de Campinas Campinas S&atilde o Paulo Brazil departamento de matemática e Estatstica Universidade Estadual de Ponta Grossa Ponta Grossa Brazil departamento de Estatstica Universidade Estadual de Campinas Campinas Brazil departamento de Biologia Estrutural e Funcional Universidade Estadual de Campinas Campinas Brazil departamento de Biologia Animal Universidade Estadual de Campinas Campinas Brazil

Temporal activity patterns in animals emerge from complex interactions between choices made by organisms as responses to biotic interactions and challenges posed by external factors. Temporal activity pattern is an inherently continuous process, even being recorded as a time series. The discreteness of the data set is clearly due to data-acquisition limitations rather than a true underlying discrete nature of the phenomenon itself. Therefore, curves are a natural representation for high-frequency data. Here, we fully model temporal activity data as curves integrating wavelets and functional data analysis, allowing for testing hypotheses based on curves rather than on scalar and vector-valued data. Temporal activity data were obtained experimentally for males and females of a small-bodied marsupial and modelled as wavelets with independent and identically distributed errors and dependent errors. The null hypothesis of no difference in temporal activity pattern between male and female curves was tested with functional analysis of variance (FANOVA). The null hypothesis was rejected by FANOVA and we discussed the differences in temporal activity pattern curves between males and females in terms of ecological and life-history attributes of the reference species. We also performed numerical analysis that shed light on the regularity properties of the wavelet bases used and the thresholding parameters.

关键词： Functional Analysis of Variance High-Frequency Data Temporal Activity Pattern Shrinkage Wavelet Thresholding

Virtual screening of flavonoids from Jatropha gossypiifolia *** potential drugs for diabetic complications

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Traditional Medicine Research 2022年第2期7卷 34-42页

作者： Yudith Cañizares-Carmenate Roberto Díaz-Amador Mirtha Mayra Gonzalez-Bedia Tan Tran Quang Nhat Francisco Torrens Juan Alberto Castillo-Garit Unit of Computer-Aided Molecular“Biosilico”Discovery and Bioinformatic Research Departamento de FarmaciaFacultad de Química-FarmaciaUniversidad Central“Marta Abreu”de Las VillasSanta Clara 54830Villa ClaraCuba departamento de Ciencias de la Computación Facultad de MatemáticaFísica y ComputaciónUniversidad CelaraCuntral“Marta Abreu”de Las VillasSanta Clara 54830Villa ClaraCuba Institut Universitari de Ciència Molecular Universitat de ValènciaEdifici d’Instituts de PaternaP.O.Box 22085ValènciaSpain. Unidad de Toxicología Experimental Universidad de Ciencias Médicas de Villa ClaraSanta Clara 50200Villa ClaraCuba.

Background:Diabetes mellitus is a chronic metabolic disease that is a risk factor for epidemic *** hyperglycemic conditions,the enzyme aldose reductase catalyzes the formation of sorbitol in the metabolism of glucose via polyols,leading to the development of diabetic ***,inhibitors of this enzyme are therapeutic targets for the prophylaxis and treatment of these ***:In this study,a generalized linear regression model was developed to analyze flavonoids-obtained from a database-that have been tested as inhibitors of aldose *** this sense,the molecular descriptors implemented in DRAGON and MATLAB software were used to determine the correlation between the chemical structure of the inhibitors and their pharmacological *** model was validated according to the Organisation for Economic Co-operation and development Standards and subsequently used for the virtual screening of the flavonoids identified in Jatropha gossypiifolia ***:The proposed model showed a good fit for its statistical parameters(R2=0.95).In addition,it showed good predictive power(R2 ext=0.94)and robustness(Q2 LOO=0.92).The experimental chemical space wherein the predictions were reliable(domain of application)was also ***,the model was used to identify 10 flavonoids from Jatropha gossypiifolia *** candidates for natural *** with a low probability of oral absorption were identified,among which the elagic acid biflavonoid showed the greatest promise(pIC50 predicted=9.75).Conclusion:The Jatropha gossypiifolia *** harbors flavonoids with high potential as inhibitors of the aldose reductase enzyme,in which the biflavonoid ellagic acid was shown to be the most promising inhibitor of the aldose reductase enzyme,suggesting its possible use in the treatment of the late complications of diabetes mellitus.

关键词： Jatropha gossypiifolia L. aldose reductase generalized linear regression model diabetic complications

Transversal Instability for the Thermodiffusive Reaction-Diffusion System

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 871-882页

作者： Michal KOWALCZYK Benoit PERTHAME Nicolas VAUCHELET departamento de Ingenieria matematica and Centro de Modelamiento matem'atico(UMI CNRS 2807) Universidad de Chile Sorbonne Universités UPMC Univ Paris 06UMR 7598Laboratoire Jacques-Louis LionsF-75005ParisFrance CNRS UMR 7598Laboratoire Jacques-Louis LionsF-75005ParisFrance INRIA-Paris-Rocquencourt EPC MAMBADomaine de VoluceauBP10578153 Le Chesnay CedexFrance

The propagation of unstable interfaces is at the origin of remarkable patterns that are observed in various areas of science as chemical reactions, phase transitions, and growth of bacterial colonies. Since a scalar equation generates usually stable waves, the simplest mathematical description relies on two-by-two reaction-diffusion systems. The authors' interest is the extension of the Fisher/KPP equation to a two-species reaction which represents reactant concentration and temperature when used for flame propagation,and bacterial population and nutrient concentration when used in *** authors study circumstances in which instabilities can occur and in particular the effect of dimension. It is observed numerically that spherical waves can be unstable depending on the coefficients. A simpler mathematical framework is to study transversal instability, which means a one-dimensional wave propagating in two space ***, explicit analytical formulas give explicitely the range of paramaters for instability.

关键词： Traveling waves Stability analysis Reaction-diffusion equation Thermodiffusive system

Bats and their vital ecosystem services:a global review

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Integrative Zoology 2022年第1期17卷 2-23页

作者： Leidy Azucena RAMÍREZ-FRÁNCEL Leidy Viviana GARCÍA-HERRERA Sergio LOSADA-PRADO Gladys REINOSO-FLÓREZ Alfonso SÁNCHEZ-HERNÁNdeZ Sergio ESTRADA-VILLEGAS Burton KLIM Giovany GUEVARA Programa de Doctorado en Ciencias Biológicas&Grupo de Investigación en Zoología(GIZ) Facultad de CienciasUniversidad del TolimaIbaguéColombia Programa para la Conservación de los Murciélagos de Colombia BogotáD.C.Colombia departamento de Biología&Grupo de Investigación en Zoología(GIZ) Facultad de CienciasUniversidad del TolimaIbaguéColombia departamento de matemáticas y Estadística Facultad de CienciasUniversidad del TolimaIbaguéColombia Yale School of the Environment Yale UniversityNew HavenConnecticutUSA Smithsonian Tropical Research Institute BalboaRepublic of Panama department of Natural History Royal Ontario MuseumTorontoOntarioCanada

Bats play crucial ecosystem services as seed dispersers,pollinators,controllers of insects,and nutrient ***,there has not been a thorough global review evaluating these roles in bats across all biogeographical regions of the *** reviewed the literature published during the last two decades and identified 283 relevant studies:78 dealt with the control of potential insect pests by bats,80 related to the suppression of other arthropods,60 on the dispersal of native or endemic seeds,11 dealt with the dispersal of seeds of introduced plants,29 on the pollination of native or endemic plants,1 study on pollination of introduced plants,and 24 on the use of guano as *** literature search showed that queries combining the terms“seed dispersal,”“insectivorous bats,”“nectarivorous bats,”“use of guano,”and“ecosystem services”returned 577 studies,but half were experimental in *** found that the evaluation of ecosystem services by bats has been mostly conducted in the Neotropical and Palearctic *** detect differences across relevant studies,and to explain trends in the study of ecosystem services provided by bats,we performed generalized linear mixed models(GLMM)fitted with a Poisson distribution to analyze potential differences among sampling *** identified 409 bat species that provide ecosystem services,752 insect species consumed by bats and 549 plant species either dispersed or pollinated by *** review summarizes the importance of conserving bat populations and the ecological services they provide,which is especially important during the current pandemic.

关键词： chiroptera ecosystem services frugivory,guano,insectivory nectarivory pest control pollination seed dispersal

Dairy Farming Systems’ Adaptation to Climate Change

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Agricultural Sciences 2016年第3期7卷 137-145页

作者： Emiliana Silva Armando Brito Mendes Henrique José Duarte Rosa CEEAplA Departamento de Ciências Agrárias Universidade dos A&#231ores Angra do Heroísmo Portugal CEEAplA Departamento de Matemática Universidade dos A&#231ores Ponta Delgada Portugal CITAA Departamento de Ciências Agrárias Universidade dos A&#231ores Angra do Heroísmo Portugal

The measure of climate change in dairy farms can be achieved by using the emissions of methane by the ruminants converted in CO2 equivalent (CO2-eq). In order to know the impact of future quotes of methane in the Azorean dairy milk farms, a decision model is built to the Azorean intensive grazing system of dairy farms. Some scenarios of methane levels reductions from 10 to 75% are considered and their impact is evaluated upon dairy farms income, level of CO2-eq emissions and intensity level of grazing system. The results have shown that any reduction of the methane level always implies a consequent decrease in income. If the CO2-eq has to be limited than there is the need to find alternative income activities for farmers in order to preserve economic sustainability.

关键词： Climate Change Dairy Economic Sustainability Greenhouse Gas Emissions

Generalization via Ultrahyperfunctions of a Gupta-Feynman Based Quantum Field Theory of Einstein’s Gravity

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Journal of Modern Physics 2020年第3期11卷 378-394页

作者： A. Plastino M. C. Rocca departamento de Física Universidad Nacional de La Plata Plata Argentina Consejo Nacional de Investigaciones Científicas y Tecnológicas (IFLP-CCT-CONICET)-C. C. 727 La Plata Argentina SThAR-EPFL Lausanne Switzerland departamento de matemática Universidad Nacional de La Plata Plata Argentina

Ultrahyperfunctions (UHF) are the generalization and extension to the complex plane of Schwartz’ tempered distributions. This effort is an application to Einstein’s gravity (EG) of the mathematical theory of convolution of Ultrahyperfunctions developed by Bollini et al. [1] [2] [3] [4]. A simplified version of these results was given in [5] and, based on them;a Quantum Field Theory (QFT) of EG [6] was obtained. Any kind of infinities is avoided by recourse to UHF. We will quantize EG by appealing to the most general quantization approach, the Schwinger-Feynman variational principle, which is more appropriate and rigorous that the popular functional integral method (FIM). FIM is not applicable here because our Lagrangian contains derivative couplings. We follow works by Suraj N. Gupta and Richard P. Feynman so as to undertake the construction of an EG-QFT. We explicitly use the Einstein Lagrangian as elaborated by Gupta [7], but choose a new constraint for the ensuing theory. In this way, we avoid the problem of lack of unitarity for the S matrix that afflicts the procedures of Gupta and Feynman. Simultaneously, we significantly simplify the handling of constraints, which eliminates the need to appeal to ghosts for guarantying unitarity of the theory. Our approach is obviously non-renormalizable. However, this inconvenience can be overcome by appealing to the mathematical theory developed by Bollini et al. [1] [2] [3] [4] [5]. Such developments were founded in the works of Alexander Grothendieck [8] and in the theory of Ultradistributions of Jose Sebastiao e Silva [9] (also known as Ultrahyperfunctions). Based on these works, an edifice has been constructed along two decades that are able to quantize non-renormalizable Field Theories (FT). Here we specialize this mathematical theory to discuss EG-QFT. Because we are using a Gupta-Feynman inspired EG Lagrangian, we are able to evade the intricacies of Yang-Mills theories.

关键词： Quantum Field Theory Einstein Gravity Non-Renormalizable Theories Unitarity

Recent QFT of Einstein’s Gravity Simplified via Ultrahyperfunctions

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Journal of Modern Physics 2020年第4期11卷 565-580页

作者： A. Plastino M. C. Rocca departamento de Física Universidad Nacional de La Plata La Plata Argentina Consejo Nacional de Investigaciones Cientícas y Tecnológicas La Plata Argentina (IFLP-CCT-CONICET)-C. C. La Plata Argentina departamento de matemática Universidad Nacional de La Plata La Plata Argentina

Previously published treatment is rather involved. Here we present a useful approximation to the concomitant derivation that yields a simpler way of handling things and still obtains results quite similar to those yielded by the exact treatment. Our approximation consists of giving the graviton field a simpler, but still quite good approximate form.

关键词： Quantum Field Theory Einstein Gravity Non-Renormalizable Theories Unitarity

Seismic imaging of the double seismic zone in the subducting slab in Northern Chile

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Earthquake Research Advances 2021年第1期1卷 25-33页

作者： Pan Lu Haijiang Zhang Lei Gao Diana Comte Laboratory of Seismology and Physics of Earth's Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefeiAnhui230026China departamento de Geofísica Advanced Mining Technology CenterFacultad de Ciencias Físicas y MatematicasUniversidad de ChileBlanco Encalada2002SantiagoChile

Double seismic zones are commonly observed in the subducting slabs in a global scale,serving as ideal examples for studying the seismogenetic mechanism of the intermediate-depth *** this study,we relocate earthquakes and determine seismic velocity models using the double-difference seismic tomography method in the northern Chile subduction zone where a double seismic zone *** results suggest that the double seismic zone in northern Chile is located at about 50-140 km depth,with an interval of approximately 20 km between the two *** upper seismic zone is characterized by relatively low Vp(~7.8-8.0 km/s),low Vs(~4.4-4.5 km/s)and high Vp/Vs(~1.85)above the depth of~90 km,while the region below~90 km is distinguished by relatively high Vp(~8.2 km/s),high Vs(~4.8 km/s)and slightly high Vp/Vs(~1.75),which may be related to a series of dehydration reactions of hydrous minerals in the subducted oceanic *** comparison,the lower seismic zone is featured by the anomaly of low Vp/Vs(~1.7),although some local areas may consist of relatively high Vp/Vs values(~1.8),possibly due to the dehydration reaction of *** on the Vp,Vs,Vp/Vs anomalies combined with previous petrological experiments and thermodynamic models,it can be derived that intermediate-depth earthquakes are mainly related to the dehydration of various hydrous minerals in the subducting *** dehydration process of hydrous minerals releases water into the subducting slab and subsequently leads to the increase of pore fluid pressure and the decrease of effective normal stress,thus causing the occurrence of brittle failure and intermediate-depth earthquakes in subduction *** imaging results of the northern Chile subduction zone further indicate that the existence of the double seismic zone is related to the dehydration process of different hydrous minerals.

关键词： Chile subduction Zone Double difference seismic tomography Double seismic zone dehydration embrittlement