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Communications in Computational Physics 2019年第6期26卷 1-34页

作者： Maria Han Veiga david a.velasco-romero Remi Abgrall Romain Teyssier Institute of Computational Science University of ZurichSwitzerland Institute of Mathematics University of ZurichSwitzerland Universidad Autonoma del Estado de Morelos Mexico Instituto de Ciencias Fisicas Universidad Nacional Aut́onoma de ḾexicoMexico

Equilibrium or stationary solutions usually proceed through the exact balance between hyperbolic transport terms and source terms. Such equilibrium solutions are affected by truncation errors that prevent any classical numerical scheme from capturing the evolution of small amplitude waves of physical significance. In order to overcome this problem, we compare two commonly adopted strategies: going to very high order and reduce drastically the truncation errors on the equilibrium solution, or design a specific scheme that preserves by construction the equilibrium exactly, the so-called well-balanced approach. We present a modern numerical implementation of these two strategies and compare them in details, using hydrostatic but also dynamical equilibrium solutions of several simple test cases. Finally, we apply our methodology to the simulation of a protoplanetary disc in centrifugal equilibrium around its star and model its interaction with an embedded planet, illustrating in a realistic application the strength of both methods.

关键词： Numerical methods benchmark well-balanced methods discontinuous Galerkin methods

Radiative loss of coherence in free electrons:a long-range quantum phenomenon

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Light(Science & Applications) 2024年第2期13卷 294-301页

作者： Cruz I.velasco Valerio Di Giulio F.Javier García de Abajo ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860Castelldefels(Barcelona)Spain ICREA-InstitucióCatalana de Recerca i Estudis Avançats Passeig Lluís Companys 2308010BarcelonaSpain

Quantum physics rules the dynamics of small objects as they interact over microscopic length ***,quantum correlations involving macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low *** long-range nature of the electromagnetic coupling between charged particles and extended objects could also trigger quantum phenomena over large ***,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupling in the presence of distant extended *** is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacting with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite *** investigated regime of large distances originates in the coupling of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material *** the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuring the vacuum temperature and nondestructively sensing the presence of distant objects.

关键词： temperature quantum macroscopic

Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents

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Neural Regeneration Research 2024年第4期19卷 846-854页

作者： Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra.velasco-Reyes Facultad de Ciencias Naturales-Exactas y de la Educación Departamento de Biología.Universidad del Cauca Departamento de Estudios Psicológicos Universidad Icesi

Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older *** factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to *** pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental *** are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%*** contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its ***,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic ***,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in *** recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s *** epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective *** we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes.

关键词： Alzheimer’s disease epigenetics genes methylation natural products

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Rumen microbial degradation of bromoform from red seaweed(Asparagopsis taxiformis)and the impact on rumen fermentation and methanogenic archaea

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Journal of Animal Science and Biotechnology 2024年第1期15卷 412-426页

作者： Pedro romero Alejandro Belanche Elisabeth Jiménez Rafael Hueso Eva Ramos-Morales Joan King Salwen Ermias Kebreab david R.Yáñez-Ruiz Estacion Experimental del Zaidin Consejo Superior de Investigaciones Cientificas(CSIC)Profesor Albareda 1Granada 18008Spain Department of Animal Production and Food Sciences University of ZaragozaMiguel Servet 177Saragossa 50013Spain Blue Ocean Barns Inc. Redwood CityCAUSA Department of Animal Science University of CaliforniaDavisCA 95618USA

Background The red macroalgae Asparagopsis is an effective methanogenesis inhibitor due to the presence of halogenated methane(CH_(4))analogues,primarily bromoform(CHBr_(3)).This study aimed to investigate the degradation process of CHBr3 from A taxiformis in the rumen and whether this process is *** in vitro batch culture system was used according to a 2×2 factorial design,assessing two A taxiformis inclusion rates[0(CTL)and 2%DM diet(AT)]and two diets[high-concentrate(HC)and high-forage diet(HF)].Incubations lasted for 72 h and samples of headspace and fermentation liquid were taken at 0,0.5,1,3,6,8,12,16,24,48 and 72 h to assess the pattern of degradation of CHBr_(3) into dibromomethane(CH_(2)Br_(2))and fermentation ***,an in vitro experiment with pure cultures of seven methanogens strains(Methanobrevibacter smithii,Methanobrevibacter ruminantium,Methanosphaera stadtmanae,Methanosarcina barkeri,Methanobrevibacter millerae,Methanorhermobacter wolfei and Methanobacterium mobile)was conducted to test the effects of increasing concentrations of CHBr3(0.4,2,10and 50μmol/L).Results The addition of AT significantly decreased CH_(4) production(P=0.002)and the acetate:propionate ratio(P=0.003)during a 72-h *** concentrations of CHBr_(3) showed a rapid decrease with nearly 90%degraded within the first 3 h of *** the contrary,CH_(2)Br_(2) concentration quickly increased during the first 6 h and then gradually decreased towards the end of the *** CHBr_(3) degradation nor CH_(2)Br_(2) synthesis were affected by the type of diet used as substrate,suggesting that the fermentation rate is not a driving factor involved in CHBr_(3)*** in vitro culture of methanogens showed a dose-response effect of CHBr3 by inhibiting the growth of ***,***,***,***,***,***,and *** The present work demonstrated that CHBr_(3) from *** is quickly degrad

关键词： Bromoform metabolism Dibromomethane metabolism Methane mitigation Methanogens Rumen microbiota Seaweed

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CONSTANS alters the circadian clock in Arabidopsis thaliana

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Molecular Plant 2024年第8期17卷 1204-1220页

作者： Pedro de los Reyes Gloria Serrano-Bueno Francisco J.romero-Campero He Gao Jose M.romero Federico Valverde Plant Development Group-Institute for Plant Biochemistry and Photosynthesis Consejo Superior de Investigaciones CientificasUniversidad de SevillaSevilleSpain Department of Computer Science and Artificial Intelligence Universidad de SevillaSevilleSpain Department of Plant Developmental Biology Max Planck Institute for Plant Breeding ResearchCologneGermany Department of Plant Biochemistry and Molecular Biology Universidad de SevillaSevilleSpain

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the *** these processes,the floral transition is essential to ensure reproductive success and is finelyregulated by several internal andexternal genetic *** photoperiodic pathway,which controls plant response to day length,is one of the most important pathways controlling *** Arabidopsis photoperiodic flowering,CONSTANS(CO)is the central gene activating the expression of the florigen FLOWERING LOCUS T(FT)in the leaves at the end of a long *** circadian clock strongly regulates Co ***,to date,no evidence has been reported regarding a feedbackloop from the photoperiod pathway back to the circadian *** transcriptional networks,we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod *** expression,chromatin immunoprecipitation experiments,and phenotypic analysis allowed us to elucidate the role of Co over the circadian *** with altered cO expression showed a different internal clock period,measured by daily leaf rhythmic *** showed that co upregulates the expression of key genes related to the circadian clock,such as CCA1,LHY,PRR5,and Gl,at the end of a long day by bindingto specific sites on their ***,a high numberof PRR5-repressed target genes are upregulated by CO,and this could explain the phase transition promoted by *** CO-PRR5 complex interacts with the bZiP transcriptionfactor HY5andhelps to localize the complex in the promoters of clock *** together,our results indicate that there may be a feedback loop in which co communicates back to the circadian clock,providing seasonal information to the circadian system.

关键词： CONSTANS circadian clock photoperiod

Enhancement of the CO_(2)adsorption and hydrogenation to CH_(4)capacity of Ru–Na–Ca/γ–Al_(2)O_(3)dual function material by controlling the Ru calcination atmosphere

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Journal of Environmental Sciences 2024年第6期140卷 292-305页

作者： Alejandro Bermejo-López Beñat Pereda-Ayo Jon A.Onrubia-Calvo JoséA.González-Marcos Juan R.González-velasco Department of Chemical Engineering Faculty of Science and TechnologyUniversidad del País Vasco UPV/EHUBarrio Sarrienas/n48940 LeioaBizkaiaSpain

Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction *** influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is *** adsorbent precursors are first co-impregnated onto alumina and calcined in ***,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))*** are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and *** catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is *** calcination atmosphere influences the physicochemical properties and,ultimately,activity of *** data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic *** calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation ***,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.

关键词： CO_(2)methanation Integrated CO_(2)capture and utilization(ICCU) Dual functional material(DFM) Ru calcination atmosphere

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Proliferative vitreoretinopathy and its relationship with inflammatory serum biomarkers

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1659-1664页

作者： Victor Alejandro Martinez Pacheco Sergio Rojas Juarez Braulio Hernan velasco Sepulveda Abel Ramirez Estudillo Hospital de Nuestra Señora de la Luz Retina and Vitreous DepartmentMexico City 06030Mexico Instituto de Oftlamología FAP Conde de Valenciana Mexico City 06080Mexico

AIM:To analyze if a relationship between levels ofinflammatory serum biomarkers and severity of primaryproliferative vitreoretinopathy(PVR)***:A retrospective case-control *** adult patients with rhegmatogenous retinaldetachment and primary PVR were included in the *** the control group,healthy adults who underwentcataract surgery were *** grade of PVR wasclassified according to the Retinal Society *** samples were obtained before surgery,and processed in MYTHIC *** of interest wereneutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyteratio(PLR),and lymphocyte-to-monocyte ratio(LMR),thetime between the decrease in visual acuity and surgery,PVRgrade,type of surgery,final best corrected visual acuity,andrate of ***:Totally 240 patients were included,120 ineach group,79(65.8%)and 56(46.7%)were male in thePVR and control group,*** A had greaterlevels of monocytes(0.28±0.18 vs 0.12±0.32,P=0.002),neutrophils(4.59±1.51 vs 3.92±1.27,P=0.006),and LMR(9.32±4.42 vs 7.43±3.90,P=0.01).PVR B had a greatermonocyte count(0.30±0.13 vs 0.12±0.32,P=0.001),andPVR C demonstrated higher levels in monocytes(0.27±0.12vs 0.12±0.32,P=0.004),neutrophils(4.39±1.13 vs3.92±1.27,P=0.004),and LMR(9.63±3.24 vs 7.43±3.90,P=0.002)compared to control,*** LMR cut-offvalue of 9.38 predicted PVR with a sensibility of 54.2%andspecificity of 77.5%and NLR cut-off of 1.70 predicted PVRwith a sensibility of 62%and specificity of 54.2%.CONCLUSION:Patients with primary PVR demonstrategreater neutrophil,monocyte,and LMR levels than thecontrol ***-off values obtained from ratios could beuseful in a clinical setting when no posterior view of thefundus is possible due to media opacity.

关键词： biomarkers proliferative vitreoretinopathy retinal detachment inflammation serum

Personality Trait Detection via Transfer Learning

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Computers, Materials & Continua 2024年第2期78卷 1933-1956页

作者： Bashar Alshouha Jesus Serrano-Guerrero Francisco Chiclana Francisco P.romero Jose A.Olivas Department of Information Technologies and Systems University of Castilla-La ManchaCiudad Real13071Spain Institute of Artificial Intelligence School of Computer Science and InformaticsDe Montfort UniversityThe GatewayLeicesterLE19BHUK

Personality recognition plays a pivotal role when developing user-centric solutions such as recommender systems or decision support systems across various domains,including education,e-commerce,or human ***-ditional machine learning techniques have been broadly employed for personality trait identification;nevertheless,the development of new technologies based on deep learning has led to new opportunities to improve their *** study focuses on the capabilities of pre-trained language models such as BERT,RoBERTa,ALBERT,ELECTRA,ERNIE,or XLNet,to deal with the task of personality *** models are able to capture structural features from textual content and comprehend a multitude of language facets and complex features such as hierarchical relationships or long-term *** makes them suitable to classify multi-label personality traits from reviews while mitigating computational *** focus of this approach centers on developing an architecture based on different layers able to capture the semantic context and structural features from ***,it is able to fine-tune the previous models using the MyPersonality dataset,which comprises 9,917 status updates contributed by 250 Facebook *** status updates are categorized according to the well-known Big Five personality model,setting the stage for a comprehensive exploration of personality *** test the proposal,a set of experiments have been performed using different metrics such as the exact match ratio,hamming loss,zero-one-loss,precision,recall,F1-score,and weighted *** results reveal ERNIE is the top-performing model,achieving an exact match ratio of 72.32%,an accuracy rate of 87.17%,and 84.41%of *** findings demonstrate that the tested models substantially outperform other state-of-the-art studies,enhancing the accuracy by at least 3%and confirming them as powerful tools for personality *** findings represent substantial a

关键词： Personality trait detection pre-trained language model big five model transfer learning

Assistive Robotics for Upper Limb Physical Rehabilitation: A Systematic Review and Future Prospects

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Chinese Journal of Mechanical Engineering 2024年第4期 63-86页

作者： Andrés Guatibonza Leonardo Solaque Alexandra.velasco Lina Pe?uela Department of Engineering Mechatronics EngineeringMilitar Nueva Granada University

Physical assistive robotics are oriented to support and improve functional capacities of people. In physical rehabilitation, robots are indeed useful for functional recovery of affected limb. However, there are still open questions related to technological aspects. This work presents a systematic review of upper limb rehabilitation robotics in order to analyze and establish technological challenges and future directions in this area. A bibliometric analysis was performed for the systematic literature review. Literature from the last six years, conducted between August 2020 and May 2021,was reviewed. The methodology for the literature search and a bibliometric analysis of the metadata are *** a preliminary search resulted in 820 articles, a total of 66 articles were included. A concurrency network and bibliographic analysis were provided. And an analysis of occurrences, taxonomy, and rehabilitation robotics reported in the literature is presented. This review aims to provide to the scientific community an overview of the state of the art in assistive robotics for upper limb physical rehabilitation. The literature analysis allows access to a gap of unexplored options to define the technological prospects applied to upper limb physical rehabilitation robotics.

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Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： david A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas