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constraining the variable generalized chaplygin gas model in matter creation cosmology

communications in Theoretical Physics 2024年第10期76卷 121-136页

作者： Yogesh Bhardwaj c P Singh Department of Applied Mathematics Delhi Technological University

We explore the variable generalized chaplygin gas（VGcG） model in the theory of matter creation cosmology within the framework of a spatially homogeneous and isotropic flat Friedmann—Lemai tre—Robertson—Walker space-time. Matter creation cosmology is based on reinterpretation of the energy–momentum tensor in Einstein's field equations. This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents. The variable chaplygin gas（VcG） is also studied as a particular solution. We use the Markov chain Monte carlo method to constrain the free parameters of three models, namely,Lambda-cold-Dark matter（ΛcDM）, VGcG and VcG models with and without matter creation from the latest observational data from baryon ac.ustic oscillations, cosmic chronometer, type Ia supernovae（Pantheon） inc.uding gamma-ray bursts, quasars and the local measurement of H0from R21 data. Two different combinations of dataset provide a fairly tight constraint on the parameters of the ΛcDM, VGcG and VcG models. The present values of various cosmological parameters are obtained, which are very close to the ΛcDM model. Furthermore, we perform stability analysis, Bayesian evidence analysis and information criteria analysis for these models through studying the sound speed, Bayes factor, and Akaike information criteria（AIc） and Bayesian information criteria（BIc） selection criteria. The values of sound speed for VGcG and VcG models shows that both the models are stable. According to AIc, it is observed that VGcG and VcG models with matter creation are supported considerably less by current observations,while BIc shows that these models are not favoured by observational data.

关键词： chaplygin gas model cosmological model dark energy matter creation

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Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to c.anges in the emission band profiles c.used by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera champika Bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi I.A.u.N.Gunatilleke c.V.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental c.ange Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily bec.use of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

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Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye Da-ming Wei Yi-ming Zhu Zhi-Ping Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China cAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into acc.unt the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

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Myotis bat STING attenuates aging-related inflammation in female mice

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Zoological Research 2024年第5期45卷 961-971页

作者： Xi Wang Jing-Kun Jia Qi Wang Jing-Wen Gong ang Li Jia Su Peng Zhou Wuhan Institute of Virology Chinese Academy of SciencesWuhanHubei 430071China Guangzhou National Laboratory Guangzhou International Bio IslandGuangzhouGuangdong 510005China university of chinese Academy of Sciences Beijing 100000China State Key Laboratory of Respiratory Disease First Affiliated Hospital of Guangzhou Medical SchoolGuangzhouGuangdong 510005China

Bats,notable as the only flying mammals,serve as natural reservoir hosts for various highly pathogenic viruses in humans(e.g.,SARS-coV and Ebola virus).Furthermore,bats exhibit an unparalleled longevity among mammals relative to their size,particularly the Myotis bats,which can live up to 40 ***,the mechanisms underlying these distinctive traits remain incompletely *** our prior research,we demonstrated that bats exhibit dampened STING-interferon activation,potentially conferring upon them the capacity to mitigate virus-or aging-induced *** substantiate this hypothesis,we established the first in vivo bat-mouse model for aging studies by integrating Myotis davidii bat STING(MdSTING)into the mouse *** monitored the genotypes of these mice and performed a longitudinal comparative transcriptomic analysis on MdSTING and wild-type mice over a 3-year aging *** transcriptomic analysis indicated a reduction in aging-related inflammation in female MdSTING mice,as evidenced by significantly lower levels of pro-inflammatory cytokines and chemokines,immunopathology,and neutrophil rec.uitment in aged female MdSTING mice compared to aged wild-type mice in *** results indicated that MdSTING knock-in attenuates the aging-related inflammatory response and may also improve the healthspan in mice in a sex-dependent *** the underlying mechanism awaits further study,this research has critical implications for bat longevity research,potentially contributing to our comprehension of healthy aging in humans.

关键词： Bat STING Longevity Aging-related inflammation Virus reservoir host

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microRNA-2184 orchestrates Mauthner-cell axon regeneration in zebrafish via syt3 modulation

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Journal of Genetics and Genomics 2024年第9期51卷 911-921页

作者： Xinghan chen Yueru Shen Zheng Song Xinliang Wang Huaitong Yao Yuan cai Zi-ang Zhao Bing Hu Hefei National Research center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefeiAnhui 230026China The First Affiliated Hospital of uSTc Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China

MicroRNAs(miRNAs)play a significant role in axon regeneration following spinal cord ***,the functions of numerous miRNAs in axon regeneration within the central nervous system(cNS)remain largely ***,we elucidate the positive role of microRNA-2184(miR-2184)in axon regeneration within zebrafish Mauthner cells(M-cells).The upregulation of miR-2184 in a single M-cell can facilitate axon regeneration,while the specific sponge-induced silencing of miR-2184 leads to impeded *** show that syt3,a downstream target of miR-2184,negatively regulates axon regeneration,and the regeneration suppression modulated by syt3 depends on its binding to ca2+.Furthermore,pharmacological stimulation of the cAMP/PKA pathway suggests that c.anges in the readily releasable pool may affect axon *** data indicate that miR-2184 promotes axon regeneration of M-cells within the cNS by modulating the downstream target syt3,providing valuable insights into potential therapeutic strategies.

关键词： Axon regeneration Axon ablation miR-2184 syt3 Readily releasable pool

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Theoretical characterization of the adsorption configuration of pyrrole on Si(100)surface by x-ray spectroscopy

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chinese Physics B 2024年第2期33卷 430-435页

作者：李好情明静姜志昂李海波马勇宋秀能 School of Physics and Electronics Shandong Normal UniversityJinan 250358China

The possible configurations of pyrrole absorbed on a Si(100)surface have been investigated by x-ray photoelectron spectroscopy(XPS)and near-edge x-ray absorption fine struc.ure(NEXAFS)*** c-1s XPS and NEXAFS spectra of these adsorption configurations have been calculated by using the density functional theory(DFT)method and fullcore hole(FcH)approximation to investigate the relationship between the adsorption configurations and the *** result shows that the XPS and NEXAFS spectra are struc.urally dependent on the configurations of pyrrole absorbed on the Si(100)*** with the XPS,the NEXAFS spectra are relatively sensitive to the adsorption configurations and can ac.urately identify *** NEXAFS decomposition spectra produced by non-equivalent carbon atoms have also been calculated and show that the spectral features vary with the diverse types of carbon atoms and their struc.ural environments.

关键词： pyrrole silicon surface x-ray photoelectron spectroscopy(XPS) near-edge x-ray absorption fine struc.ure(NEXAFS)

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IgE-Mast cell mediated allergy: a sensor of food quality

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Signal Transduction and Targeted Therapy 2024年第1期9卷 8-9页

作者： christopher c.udoye Rudolf A.Manz Institute for Systemic Inflammation Research University of LübeckLübeckGermany

In two recent studies published in Nature,Florsheim et *** Plum et *** that allergic-specific reactions induced by immunoglobulin(Ig)E mediated mast cell activation is c.ucial for the timely induction of antigen-avoidance behaviour.1,2 These studies prove the concept that allergic sensitization triggers the formation of avoidance behaviour and define the underlying molecular mechanism.

关键词： allergic mechanism

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Leveraging the potential of big genomic and phenotypic data for genome-wide association mapping in wheat

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The crop Journal 2024年第3期12卷 803-813页

作者： Moritz Lell Yusheng Zhao Jochen c.Reif Leibniz Institute of Plant Genetics and crop Plant Research(IPK) Corrensstraße 3D-06466 SeelandGermany

Genome-wide association mapping studies(GWAS)based on Big Data are a potential approach to improve marker-assisted selection in plant *** number of available phenotypic and genomic data sets in which medium-sized populations of several hundred individuals have been studied is rapidly *** these data and using them in GWAS c.uld increase both the power of QTL discovery and the ac.uracy of estimation of underlying genetic effects,but is hindered by data heterogeneity and lack of *** this study,we used genomic and phenotypic data sets,focusing on central European winter wheat populations evaluated for heading *** explored strategies for integrating these data and subsequently the resulting potential for *** interoperability between data sets was greatly aided by some overlapping genotypes and a linear relationship between the different phenotyping protocols,resulting in high quality integrated phenotypic *** this context,genomic prediction proved to be a suitable tool to study relevance of interactions between genotypes and experimental series,which was low in our *** to expectations,fewer associations between markers and traits were found in the larger combined data than in the individual experimental ***,the predictive power based on the marker-trait associations of the integrated data set was higher across data ***,the results show that the integration of medium-sized to Big Data is an approach to increase the power to detect QTL in *** results enc.urage further efforts to standardize and share data in the plant breeding community.

关键词： Big Data Genome-wide association study Data integration Genomic prediction Wheat

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Learning about good nutrition with the 5-color front-of-package label"Nutri-Score":an experimental study

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Food Science and Human Wellness 2024年第3期13卷 1195-1200页

作者： Robin c.Hau Klaus W.Lange university of Applied Sciences Landshut Landshut 84036Germany Faculty of Human Sciences University of RegensburgRegensburg 93040Germany

The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food *** impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect *** the present study,we have investigated how student participants c.ange a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the Nutri-Scores of the available food *** were instructed to compose a healthy diet plan in order that the question of whether the NutriScore would improve their ability to compose a healthy dietary plan c.uld be investigated,independent of the question of whether they would apply this knowledge in their ordinary *** found a substantial(cohen's d=0.86)positive impact on nutritional quality(as measured by the Nutrient Profiling System score of the Food Standards Agency)and a medium-sized(cohen's d=0.43)reduction of energy *** content reduction was larger for participants who had initially composed plans with higher energy *** results suggest that the Nutri-Score has the potential to guide consumers to healthier food *** remains unclear,however,whether this potential will be reflected in real-life dietary choices.

关键词： Nutri-Score Front-of-package label Nudge Nutrition Health

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