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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 255-274页

作者： Y.El jariri F.L.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEA FSSM Université Cadi Ayyad Observatoire de l'Oukaimeden LPHEA FSTG Université Cadi Ayyad Département de physique Université d'Anvers LICPM ENSA-BM Université Sultan Moulay Slimane

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating stars. In this article, we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 yr. We based ourselves, on the one hand,on 1268 spectra(41 nights of observation) recorded between the years 1994 and 1997 at the Observatory of haute Provence(OHP, France) previously observed by Chadid and Gillet, and on the other hand on 1569 spectra(46nights of observation) recorded at our Oukaimeden Observatory(Morocco) between 2015 and 2016. Through this study, we have detected information on atmospheric dynamics that had not previously been detected. Indeed, the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases. A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as well. For the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of Fe Ⅱ(λ4923.921 ?) increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko cycle. Furthermore, we found that the Van Hoof effect is also modulated by the Blazhko effect.Thus, toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle, this effect is minimal. We also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper atmosphere. When observed over a long time, we can interpret it as a function of the Blazhko phases.

关键词： shock waves stars: atmospheres stars: individual (RR Lyr) stars: variables: RR Lyrae techniques: radial velocities techniques: spectroscopic

Microplastics and microbiota:Unraveling the hidden environmental challenge

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World Journal of Gastroenterology 2024年第16期30卷 2191-2194页

作者： Jean demarquoy universitéde Bourgogne Institut Agro-DijonDijon 21000France

This editorial explores the intricate relationship between microplastics(MPs)and gut microbiota,emphasizing the complexity and environmental health implications.The gut microbiota,a crucial component of gastrointestinal health,is examined in the context of potential microbial degradation of MPs.Furthermore,dysbiosis induced by MPs emerges as a consensus,disrupting the balance of gut microbiota and decreasing diversity.The mechanisms triggering dysbiosis,including physical interactions and chemical composition,are under investigation.Ongoing research addresses the consequences of MPs on immune function,nutrient metabolism,and overall host health.The bidirectional relationship between MPs and gut microbiota has significant implications for environmental and human health.despite uncertainties,MPs negatively impact gut microbiota and health.Further research is essential to unravel the complex interactions and assess the long-term consequences of MPs on both environmental and human well-being.

关键词： Microplastics Microbiota Gut Dysbiosis

Immunobiodiversity:Conserved and specific immunity across land plants and beyond

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Molecular Plant 2024年第1期17卷 92-111页

作者： Baptiste Castel Karima El Mahboubi Christophe Jacquet Pierre-Marc delaux Laboratoire de Recherche en Sciences Végétales(LRSV) Universitéde ToulouseCNRSUPSToulouse INPCastanet-TolosanFrance

Angiosperms represent most plants that humans cultivate,grow,and eat.However,angiosperms are only one of five major land plant lineages.As a whole lineage,plants also include algal groups.All these clades represent a tremendous genetic diversity that can be investigated to reveal the evolutionary history of any given mechanism.In this review,we describe the current model of the plant immune system,discuss its evolution based on the recent literature,and propose future directions for the field.In angiosperms,plant–microbe interactions have been intensively studied,revealing essential cell surface and intracellular immune receptors,as well as metabolic and hormonal defense pathways.Exploring diversity at the genomic and functional levels demonstrates the conservation of these pathways across land plants,some of which are beyond plants.On basis of the conserved mechanisms,lineage-specific variations have occurred,leading to diversified reservoirs of immune mechanisms.In rare cases,this diversity has been harnessed and successfully transferred to other species by integration of wild immune receptors or engineering of novel forms of receptors for improved resistance to pathogens.We propose that exploring further the diversity of immune mechanisms in the whole plant lineage will reveal completely novel sources of resistance to be deployed in crops.

关键词： evolution MPMI immunity plant evoMPMI symbiosis

Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults

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Journal of Sport and Health Science 2024年第3期13卷 409-418页

作者： Jérémy Raffin Yves Rolland Annelise Genoux Guillaume Combes Mikael Croyal Bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group Institut du Vieillissement Gérontopôle de ToulouseCentre Hospitalo-Universitaire de ToulouseToulouse 31000France Centre d'Epidémiologie et de Recherche en Santédes Populations UnitéMixte de Recherche 1295Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse-III-Paul-SabatierToulouse 31000France LimitAging Team Institut des Maladies Métaboliques et CardiovasculairesUnitéMixte de Recherche 1297Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse III-Paul SabatierToulouse 31432France Service de Biochimie Pôle de biologieHôpital de PurpanCentre Hospitalo-Universitaire de ToulouseToulouse 31300France L'Institut du Thorax Institut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France BioCore US16Structure Fédérative de Recherche BonamyInstitut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France Plate-forme de spectrométrie de masse Centre de Recherche en Nutrition HumaineOuestNantes 44000France 不详

Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy metabolism.IF1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains unclear.Additionally,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP synthase.We examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these associations.Methods:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were included.IF1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year visit.Multiple linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 concentrations.Mediation analyses were conducted to examine whether apoA-I mediated these associations.Mixedeffect linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in PA.Results:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly mediates this association.Additionally,this study f

关键词： Aging Apolipoprotein Bioenergetics Exerkine Mitochondria

A digital twin model-based approach to cost optimization of residential community microgrids

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Global Energy Interconnection 2024年第1期7卷 82-93页

作者： Mariem dellaly Sondes Skander-Mustapha Ilhem Slama-Belkhodja université de Tunis El Manar Ecole Nationale d’Ingénieurs de TunisLR11ES15 Laboratoire de Systèmes Electriques1002TunisTunisie université de Carthage Ecole Nationale d’Architecture et d’UrbanismeLaboratoire de Systèmes Electriques1002TunisTunisie

This paper presents a peer-to-peer community cost optimization approach based on a single-prosumer energy management system.Its objective is to optimize energy costs for prosumers in the community by enhancing the consumption efficiency.This study was conducted along two main axes.The first axis focuses on designing a digital twin for a residential community microgrid platform.This phase involves data collection,cleaning,exploration,and interpretation.Moreover,it includes replicating the functionality of the real platform and validating the results.The second axis involves the development of a novel approach that incorporates two distinct prosumer behaviors within the same community microgrid,while maintaining the concept of peer-to-peer energy trading.Prosumers without storage utilize their individual PV systems to fulfill their energy requirements and inject excess energy into a local microgrid.Meanwhile,a single prosumer with a storage system actively engages in energy exchange to maximize the community’s profit.This is achieved by optimizing battery usage using a cost optimization solution.The proposed solution is validated using the developed digital twin.

关键词： Energy management system(EMS) Cost optimization Digital twin Photovoltaic systems Microgrid

Exploring impedance spectrum for lithium-ion batteries diagnosis and prognosis: A comprehensive review

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Journal of Energy Chemistry 2024年第8期95卷 464-483页

作者： Xinghao Du Jinhao Meng Yassine Amirat Fei Gao Mohamed Benbouzid university of Brest School of Electrical Engineering Xi'an Jiaotong University ISEN Yncréa Ouest université de Technolgie de Belfort-Montbéliard

Lithium-ion batteries have extensive usage in various energy storage needs, owing to their notable benefits of high energy density and long lifespan. The monitoring of battery states and failure identification are indispensable for guaranteeing the secure and optimal functionality of the batteries. The impedance spectrum has garnered growing interest due to its ability to provide a valuable understanding of material characteristics and electrochemical processes. To inspire further progress in the investigation and application of the battery impedance spectrum, this paper provides a comprehensive review of the determination and utilization of the impedance spectrum. The sources of impedance inaccuracies are systematically analyzed in terms of frequency response characteristics. The applicability of utilizing diverse impedance features for the diagnosis and prognosis of batteries is further elaborated. Finally,challenges and prospects for future research are discussed.

关键词： Lithium-ion battery Impedance spectrum Temperature monitoring Failure diagnosis Health prognosis

Monolithic metal-based/porous carbon nanocomposites made from dissolved cellulose for use in electrochemical capacitor

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Green Carbon 2024年第1期2卷 109-117页

作者： Madhav P.Chavhan Arjeta Kryeziu Somenath Ganguly Julien Parmentier university of Ostrava Faculty of Science30.dubna 22Ostrava 70103Czech Republic universitéde Strasbourg Universitéde Haute-AlsaceInstitut de Science des Matériaux de Mulhouse(IS2M)UMR 7361 CNRS-UHA15 rue Jean StarckyBP 248868057 Mulhouse CedexFrance Indian Institute of Technology Kharagpur Department of Chemical EngineeringKharagpurIndia

Porous metal-based carbon nanocomposites,with a monolithic shape,were prepared by a one-pot synthesis from dissolved cellulose and metallic salts using a simple,cheap,and environmentally friendly route.Their potential performances as electrochemical capacitors were tested with three metal precursors(M=Cu,Mn,and Fe)with two loadings and in an asymmetric cell for the Fe-based carbon material.Interestingly,here soluble metal precursors were not deposited on a hard cellulose template but mixed in a precooled concentrated NaOH solution where cellulose was previously dissolved,allowing for a good dispersion of the metallic species.After a freezing step where concomitant cellulose regeneration and pore ice-templating phenomena took place,followed by a carbonization step,the mixture led to a porous carbon monolith embedding well-dispersed metal-based nanoparticles having a diameter below 20 nm and present as metallic,oxide,or carbide phase(s)according to the element M.These materials were characterized by different physicochemical techniques and electrochemical tests.Their performances as supercapacitors are discussed in light of the specific behaviour of the metal-based phase and its influence on the carbon matrix properties such as mesopore formation and carbon graphitization.An asymmetric energy storage cell assembled with a Fe-based carbon electrode against a carbon xerogel electrode derived from a phenolic resin shows specific energy and power of 18.3 Wh kg^(−1)at 5 mA cm^(−2)and 1.6 kW kg^(−1)at 25 mA cm^(−2),respectively.

关键词： Cellulose Metal-based carbon nanocomposite Nanoparticles Monolith Supercapacitor

Taurine: a promising nutraceutic in the prevention of retinal degeneration

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Neural Regeneration Research 2024年第3期19卷 606-610页

作者： Diego García-Ayuso Johnny Di Pierdomenico Ana Martínez-Vacas Manuel Vidal-Sanz Serge Picaud María PVillegas-Pérez Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la SaludMurciaEspaña Sorbonne université INSERMCNRSInstitut de la VisionParisFrance

Taurine is considered a non-essential amino acid because it is synthesized by most mammals.However,dietary intake of taurine may be necessary to achieve the physiological levels required for the development,maintenance,and function of certain tissues.Taurine may be especially important for the retina.The concentration of taurine in the retina is higher than that in any other tissue in the body and taurine deficiency causes retinal oxidative stress,apoptosis,and degeneration of photoreceptors and retinal ganglion cells.Low plasma taurine levels may also underlie retinal degeneration in humans and therefore,taurine administration could exert retinal neuroprotective effects.Taurine has antioxidant,anti-apoptotic,immunomodulatory,and calcium homeostasis-regulatory properties.This review summarizes the role of taurine in retinal health and disease,where it appears that taurine may be a promising nutraceutical.

关键词： amino acid anti-inflammatory antioxidant gamma-aminobutyric acid nutraceutical photoreceptor degeneration retina retinitis pigmentosa taurine

Numerical Simulation of Turbulent Diffusion Flames of a Biogas Enriched with Hydrogen

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Fluid Dynamics & Materials Processing 2024年第1期20卷 79-96页

作者： Naima Krarraz Amina Sabeur Khadidja Safer Ahmed Ouadha Laboratoire des Science et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des Carburants Gazeux et de l’Environnement Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic fermentation of organic materials has the advantage of being an environmentally friendly biofuel.Nevertheless,the relatively low calorific value of such gases makes their effective utilization in practical applications relatively difficult.The present study considers the addition of hydrogen as a potential solution to mitigate this issue.In particular,the properties of turbulent diffusion jet flames and the related pollutant emissions are investigated numerically for different operating pressures.The related numerical simulations are conducted by solving the RANS equations in the frame of the Reynolds Stress Model in combination with the flamelet approach.Radiation effects are also taken into account and the combustion kinetics are described via the GRI-Mech 3.0 reaction model.The considered hydrogen fuel enrichment spans the range from 0%to 50%in terms of volume.Pressure varies between 1 and 10 atm.The results show that both hydrogen addition and pressure increase lead to an improvement in terms of mixing quality and have a significant effect on flame temperature and height.They also reduce CO_(2) emissions but increase NOx production.Prompt NO is shown to be the predominant NO formation mechanism.

关键词： Biogas hydrogen diffusion flame turbulence NO formation route pressure