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Consequences of a two-time relativistic Bohmian model

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Communications in Theoretical Physics 2024年第7期76卷 63-73页

作者： Giuseppe Raguni departamento de Fisica Universidad de MurciaE-30071 MurciaSpain

Effects of a Bohmian type quantum-relativistic theory are *** model is obtained by introducing a new and independent time parameter whose relative motions are not directly observable and cause quantum uncertainties of the physical *** the usual de Broglie-Bohm theories,the Quantum Potential does not directly affect the observable motion,but determines the one that is relative to the new time *** turns out that the Zitterbewegung of a free particle,of which a more general law is obtained,is the key example of these hidden motions and,through it,it seems possible to give physical reality to the Feynman's paths.A relativistic revision of the uncertainty principle is also derived from the theory.

关键词： Quantum Mechanics Foundations de Broglie-Bohm theory Zitterbewegung uncertainty principle verification extra dimensions

Comparing Fine-Tuning, Zero and Few-Shot Strategies with Large Language Models in Hate Speech detection in English

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2849-2868页

作者： Ronghao Pan JoséAntonio García-Díaz Rafael Valencia-García departamento de Informática y Sistemas Universidad de MurciaCampus de EspinardoMurcia30100Spain

Large Language Models(LLMs)are increasingly demonstrating their ability to understand natural language and solve complex tasks,especially through text *** of the relevant capabilities is contextual learning,which involves the ability to receive instructions in natural language or task demonstrations to generate expected outputs for test instances without the need for additional training or gradient *** recent years,the popularity of social networking has provided a medium through which some users can engage in offensive and harmful online *** this study,we investigate the ability of different LLMs,ranging from zero-shot and few-shot learning to *** experiments show that LLMs can identify sexist and hateful online texts using zero-shot and few-shot approaches through information ***,it is found that the encoder-decoder model called Zephyr achieves the best results with the fine-tuning approach,scoring 86.811%on the Explainable detection of Online Sexism(EDOS)test-set and 57.453%on the Multilingual detection of Hate Speech Against Immigrants and Women in Twitter(HatEval)***,it is confirmed that the evaluated models perform well in hate text detection,as they beat the best result in the HatEval task *** error analysis shows that contextual learning had difficulty distinguishing between types of hate speech and figurative ***,the fine-tuned approach tends to produce many false positives.

关键词： Hate speech detection zero-shot few-shot fine-tuning natural language processing

Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： Carlos Magno O Pereira Frankbelson dos S Azevedo Luís Fernando C Pereira Edilberto O Silva departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

HVSR analysis of pumice sands for sediment depth characterization:A case study for Guadalajara,Mexico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado M. Alejandro Ramírez-Gaytan Adolfo Preciado Christian R.Escudero departamento de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico departamento de Ciencias Computacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico departamento del Hábitat y desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,*** to other Latin American cities,Guadalajara is exposed to high seismic risk,with the particularity of being the largest urban settlement in Latin America built on pumice *** has not yet been tested to characterize subsoil depths in pumice *** to the questionable use of traditional geotechnical tests for the analysis of pumice soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak amplitude(A0)are used to constrain the depth of the major impedance contrast that represents the interface between bedrock and pumice *** were compared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estimated on the riverbanks that cross the city,reveals different subsoil thickness that could have an impact on different site responses on riverine areas to an eventual *** and academic efforts are combined in this work to characterize depth sediments,an important parameter that impacts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pumice soil characterization

Temporal stability and directional change in a color cline of a marine snail from NW Spain

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Current Zoology 2024年第2期70卷 163-173页

作者： Juan Gefaell Ramon Vigo A.Honorato Gonzalez-Vazquez Juan Galindo Emilio Rolan-Alvarez Centro de Investigacion Marina Universidade de VigoDepartamento de BioquimicaGenetica e Inmunologia36310 VigoSpain

The evolution and maintenance of color clines is a classic topic of research in evolutionary ***,studies analyzing the temporal dynamics of such clines are much less frequent,due to the difficulty of obtaining reliable data about past color distributions along environmen-tal *** this article,we describe a case of decades-long temporal stability and directional change in a color cline of the marine snail Littorina saxatilis along the coastal inlet of the Ria de Vigo(NW Spain).*** from this area shows a clear color cline with 3 distinct areas from the innermost to the more wave-exposed localities of the Ria:the inner,protected localities show an abundance of fawn-like individuals;the intermediate localities show a high diversity of colors;and the outer,wave-exposed localities show populations with a high frequency of a black and lineated *** compare data from the 1970s and 2022 in the same localities,showing that the cline has kept relatively stable for at least over half a century,except for some directional change and local variability in the frequency of certain *** regression analyses and biodiversity measures are presented to provide clues into the selective pressures that might be involved in the maintenance of this color *** research avenues to properly test the explanatory power of these selective agents as well as the possible origins of the cline are discussed.

关键词： clinal variation color polymorphism ecological gradient Littorina saxatilis natural selection wave exposure.

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics Letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar Sánchez-López Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Quasilinear elliptic problems with exponential growth via the Nehari manifold method: Existence of nonnegative and nodal solutions

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Acta Mathematica Sinica,English Series 2024年

作者： Giovany FIGUEIREDO Sandra Moreira Ricardo Ruviaro Address departamento de Matematica Universidade de Brasilia departamento de Matematica e Informatica Universidade Estadual do Maranhao departamento de Matematica Universidade de Brasilia

In this paper we will be concerned with the problem -Δu-1/2Δ(a（x）u2)u+V（x）u=f（u）,x∈R2，where V is a potential continuous and f : R → R is a superlinear continuous function with exponential subcritical or exponential critical growth. We use as a main tool the Nehari manifold method in order to show existence of nonnegative solutions and existence of nodal solutions. Our results complement the classical result of solutions for quasilinear Schrodinger equations via the Nehari method due to Jia-quan Liu, Ya-qi Wang and Zhi-Qiang Wang in the sense that in this article we are considering nonlinearity of the exponential type.

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Gustatory responsiveness in Vespula germanica workers:exploring the interplay between sensory perception and task specialization

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Insect Science 2024年第2期31卷 587-598页

作者： Analia Mattiacci Carolina Mengoni Gonalons MaitéMasciocchi Juan C.Corley Grupo de Ecologia de Poblaciones de Insectos IFAB(CONICETINTA EEA Bariloche)BarilocheArgentina departamento de Ecologia Centro Regional Universitario BarilocheUniversidad Nacional Del ComahueBarilocheArgentina departamento de Biodiversidad y Biologia Experimental Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina

Workers'task specialization and division of labor are critical features of social insects'ecological *** has been proposed that the division of labor relies on response threshold models:individuals varying their sensitivity(and responsiveness)to biologically relevant stimuli and performing a specific task when a stimulus exceeds an internal *** this work,we study carbohydrate and protein responsiveness and their relation to worker task specialization in Vespula germanica,an invasive social *** sucrose and peptone responsiveness of two different subcastes,preforagers and foragers,was determined by stimulating the antenna of the wasps with increasing concentrations of the solution and quantifying whether each concentration elicited a licking *** studied responsiveness in five different ways:(1)response threshold,(2)concentration 50(concentration to which at least 50%of wasps responded),(3)maximum response,(4)mean scores and(5)median *** results suggest that V germanica foragers are more sensitive to sucrose(lower thresholds)than preforager ***,we found no differences for peptone thresholds(i.e.,a protein resource).Nonetheless,this is the first study to investigate response thresholds for protein *** intercaste variation in sucrose responsiveness shown in our work contributes to the existing knowledge about response threshold theory as a mechanism for task specialization observed in V germanica.

关键词： carbohydrates responsiveness division of labor protein responsiveness response thresholds models social insect yellow jacket

A Rapid Parameter of Enzyme-Treated Cellulosic Material Revealed by Reducing Sugar Release

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Journal of Renewable Materials 2024年第3期12卷 539-551页

作者： Verônica Távilla Ferreira Silva Adriane Maria Ferreira Milagres departamento de Biotecnologia Escola de Engenharia de LorenaUniversidade de São PauloLorenaSP12602-810Brazil

This study was conducted to evaluate the effectiveness of enzymes in purifying and reducing the degree of polymerization of cellulose for the production of dissolving *** goal was to determine the contributions of xylanase(X)and endoglucanase(EG)in the treatment of pulp,specifically by quantifying the formation of soluble and insoluble reducing sugars using the dinitrosalycilic acid(DNS)***,the release of soluble reducing sugars(RSSol)was enhanced after xylanase treatment,while endoglucanase(EG)treatment led to changes in insoluble reducing sugars(RSIns).The maximum synergism was observed for RSIns when a high ratio of endoglucanase to xylanase(320EG:5X/g pulp)was *** relative contribution of endoglucanase to RSins was determined to be 15.6%of the total reducing *** viscosity of pulps treated with xylanase decreased only by 7%,whereas endoglucanase treatment significantly reduced viscosity by 45%.Modifications in the particle size were observed after pulp treatment with the combination of endoglucanase and *** summary,the DNS test is a rapid and effective method for evaluating the efficiency of enzyme treatments on *** measurement of RSIns correlates with changes in pulp viscosity to different extents,providing valuable insights into the effectiveness of enzyme treatments.

关键词： Endoglucanase xylanase cellulose fiber pulp synergism