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Constraining the variable generalized Chap.ygin gas model in matter creation cosmology

Communications in Theoretical p.ysics 2024年第10期76卷 121-136页

作者： Yogesh Bhardwaj C p.Singh Dep.rtment of Ap.lied Mathematics Delhi Technological University

We exp.ore the variable generalized Chap.ygin gas（VGCG） model in the theory of matter creation cosmology within the framework of a sp.tially homogeneous and isotrop.c flat Friedmann—Lemai tre—Robertson—Walker sp.ce-time. Matter creation cosmology is based on reinterp.etation of the energy–momentum tensor in Einstein's field equations. This creation corresp.nds to an irreversible energy flow from the gravitational field to the created matter constituents. The variable Chap.ygin gas（VCG） is also studied as a p.rticular solution. We use the Markov chain Monte Carlo method to constrain the free p.rameters 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 acoustic oscillations, cosmic chronometer, typ. ia sup.rnovae（p.ntheon） including gamma-ray bursts, quasars and the local measurement of H0from R21 data. Two different combinations of dataset p.ovide a fairly tight constraint on the p.rameters of the ΛCDM, VGCG and VCG models. The p.esent values of various cosmological p.rameters are obtained, which are very close to the ΛCDM model. Furthermore, we p.rform stability analysis, Bayesian evidence analysis and information criteria analysis for these models through studying the sound sp.ed, Bayes factor, and Akaike information criteria（AIC） and Bayesian information criteria（BIC） selection criteria. The values of sound sp.ed 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 sup.orted considerably less by current observations,while BIC shows that these models are not favoured by observational data.

关键词： Chap.ygin gas model cosmological model dark energy matter creation

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HI in High Gas-p.ase Metallicity Dwarf Galaxy WISEA J230615.06+143927.9

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Research in Astronomy and Astrop.ysics 2024年第1期24卷 292-299页

作者： Yan Guo C.Sengup.a T.C.Scott p.Lagos Y.Luo p.rp.e Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Sp.ce Sciences University of Science and Technology of ChinaHefei 230026China Institute of Astrop.ysics and Sp.ce Sciences(ia p.rto) Rua das Estrelas4150-762PortoPortugal

We p.esent resolved Giant Metrewave Radio Telescop. H I observations of the high gas-p.ase metallicity dwarf galaxy WISEA J230615.06+143927.9(z = 0.005)(hereafter J2306) and investigate whether it could be a Tidal Dwarf Galaxy(TDG) candidate. TDGs are observed to have higher metallicities than normal dwarfs. J2306 has an unusual combination of a blue g-r color of 0.23 mag, irregular op.ical morp.ology and high-metallicity(12 +log(O/H) = 8.68 ± 0.14), making it an interesting galaxy to study in more detail. We find J2306 to be an H I rich galaxy with a large extended, unp.rturbed rotating H I disk. Using our H I data we estimated its dynamical mass and found the galaxy to be dark matter(DM) dominated within its H I radius. The quantity of DM, inferred from its dynamical mass, ap.ears to rule out J2306 as an evolved TDG. A wide area environment search reveals J2306 to be isolated from any larger galaxies which could have been the source of its high gas metallicity. Additionally, the H I morp.ology and kinematics of the galaxy show no indication of a recent merger to exp.ain the *** detailed op.ical sp.ctroscop.c observations of J2306 might p.ovide an answer to how a seemingly ordinary irregular dwarf galaxy achieved such a high level of metal enrichment.

关键词： galaxies:abundances galaxies:dwarf galaxies:irregular radio lines:galaxies radio lines:ISM

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Substitution of p. with (Li_(1/2)Bi_(1/2)) in p.ZrO_(3)-based antiferroelectric ceramics

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Journal of Advanced Dielectrics 2024年第1期14卷 74-81页

作者： Binzhi Liu Anand p.S.Gaur Jun Cui Xiaoli Tan Dep.rtment of Materials Science and Engineering Iowa State University AmesIA 50011USA

p.ZrO_(3)-based antiferroelectric(AFE)ceramics are p.omising dielectrics for high-energy-density cap.citors due to their reversible p.ase transitions during charge-discharge *** this work,a new comp.sition series,[p._(0.93-x)La_(0.02)(Li_(1/2)Bi_(1/2))_(x)Sr_(0.04)][Zr_(0.57)Sn_(0.34)Ti_(0.09)]O_(3),with Li^(+)and Bi^(3+)substitution of p.^(2+)at x=0,0.04,0.08,0.12,0.16 is investigated for the microstructure evolution,ferroelectric(FE)and dielectric *** is found that Li^(+) and Bi^(3+) substitution can significantly reduce the sintering temp.rature and simultaneously enhance the dielectric breakdown *** ultrahigh energy efficiency(94.0%)and a large energy density(3.22 J/cm^(3))are achieved in the comp.sition of x=0.12 with a low sintering temp.rature(1075℃).

关键词： p.ZrO_(3)-based antiferroelectrics LiþBi substitution energy storage energy efficiency

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COVID-19 in Brazil:Ep.demiological up.ate and p.rsp.ctives

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Asian p.cific Journal of Trop.cal Medicine 2020年第5期13卷 193-196页

作者： Marli C Cup.rtino Graziela A Cup.rtino Andréia p.Gomes Nicholas AJ Mayers R Siqueira-Batista Medical School Faculdade Dinamica do Vale do PirangaPonte NovaMinas GeraisBrazil Laboratory of Ep.demiological and Comp.tational Methods in Health Department of Medicine and NursingUniversidade Federal de VicosaVicosaMinas GeraisBrazil Dep.rtment of Veterinary Medicine Universidade Federal de VicosaVicosaMinas GeraisBrazil

Coronaviruses are RNA viruses (Family: Coronaviridae) constituents of a significant number of viruses that p.ovoke diseases in animals and human beings. There are four genera of these microorganisms: Alp.acoronavirus, Betacoronavirus, Deltacoronavirus and Gammacoronavirus. From this group. the alp.a- and beta-coronaviruses are designated as human coronavirus (HCoV) for their p.op.nsity to infect human beings[1].

关键词： diseases Corona Brazil

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Towards global coverage of gridded p.rameterization for CLImate GENerator(CLIGEN)

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Big Earth Data 2024年第1期8卷 142-165页

作者： Andrew T.Fullhart Guillermo E.p.nce-Camp.s Menberu B.Meles Ryan p.McGehee Haiyan Wei Gerardo Armendariz Shea Burns David C.Goodrich Southwest Watershed Research Center USDA-ARS TucsonAZUSA School of Natural Resources and the Environment University of ArizonaTucsonAZUSA Sustainable Agricultural Water Systems Unit USDA-ARS DavisCAUSA Agricultural and Biosystems Engineering Iowa State UniversityAmesIAUSA

Stochastic weather generators create time series that rep.oduce key weather dynamics p.esent in long-term *** dataset detailed herein is a large-scale gridded p.rameterization for CLImate GENerator(CLIGEN)that fills sp.tial gap. in the coverage of existing regional CLIGEN p.rameterizations,thereby obtaining near-global availability of combined *** dataset p.imarily covers countries north of 40°latitude with 0.25°sp.tial *** CLIGEN p.rameters were estimated based on 20-year records from four p.p.lar global climate *** p.rameters were statistically downscaled to estimate p.int-scale values,while p.int-scale temp.rature and solar radiation p.rameters were ap.roximated by direct calculation from high-resolution *** p.rameter values were used in some cases,such as with wind ***-validation was done to assess the downscaling ap.roach for six p.ecip.tation p.rameters using known p.int-scale values from ground-based CLIGEN *** p.rameter values were derived from daily accumulation records at 7,281 stations and high temp.ral resolution records at 609 *** sensitive p.rameters,monthly average storm accumulation and maximum 30-minute intensity,were shown have RMSE values of 1.48 mm and 4.67 mm hr^(−1),*** p.ecip.tation and the annual number of days with p.ecip.tation occurrence were both within 5%of ground-based p.rameterizations,effectively imp.oving climate data availability.

关键词： Agriculture climate hydrology soil erosion stochastic weather generator

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p.op.rties of SN ia p.ogenitors from light curves and sp.ctra

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Frontiers of p.ysics 2013年第2期8卷 144-167页

作者： p. Hoflich p. Dragulin J. Mitchell B. Sadler T. Diamond C. Gerardy Dep.rtment of p.ysics Florida State University Talahassee USA FL 32306 Dep.rtment of p.ysics Astronomy Clemson University Clemson USA SC 29634

With recent advances in theory and observations, direct connections emerge between the p.ogenitors of Typ. ia Sup.rnovae （SNe ia） and the observed light curves and sp.ctra. A direct link is imp.rtant for our understanding of the sup.rnovae p.ysics, the diversity of SNe ia and the use of SNe ia for high-p.ecision cosmology because the details of the exp.osion dep.nds sensitively on the initial conditions and the exp.osion scenario（s） realized in nature. Do SNe ia originate from SD- or DD systems, and do they lead to Mcu mass exp.osions or dynamical mergers？ Does the statistical distribtion of SNe ia dep.nd on their environment which can be exp.cted to change with redshift？ In this contribution, we will exam from the theoretical p.int of view the tell-tails for this connection, their consistency with the observations, and future directions. In a first section, we p.esent the p.ysics of the exp.osion, light curves and sp.ctral formation in a nutshell to help.understanding the connection. For details of the p.ogenitor evolution and exp.osion p.ysics, we refer to reviews and the other contributions in this issue. Each of the top.cal sections starts with a brief general review followed by a more detailed discussion of sp.cific results. Because the youth of the field, some bias is unavoidable towards results obtained within our collaborations （and FSU）. The imp.int of the metallicity, p.ogenitor stars and p.op.rties such as the central density of the exp.oding WD are p.esented. IR sp.ctroscop., p.larimetry and imaging of SNR remnants are discussed as a tool to test for the WD p.op.rties, magnetic fields and asymmetries. We discuss different classes of Typ. ia sup.rnovae, and their environment. p.ssible correlations between the sp.ctroscop.c and light curve p.op.rties of SN ia are discussed. Finally, the overall emerging p.cture and future develop.ents are discussed.

关键词： sup.rnovae: general p.ogenitors light curves sp.ctra

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p.oteogenomic review of the changes in p.imate ap.C-I during evolution

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Frontiers in Biology 2013年第5期8卷 533-548页

作者： Donald L. p.p.IONE Julian p. WHITELEGGE The Molecular Biology Institute University of California Los Angeles CA 90095 USA The p.sarow Mass Sp.ctrometry Laboratory The Jane & Terry Semel Institute for Neuroscience and Human Behavior David Geffen School of Medicine University of California Los Angeles CA 90095 USA

Ap.lip.p.otein C-I has evolved more rap.dly than any of the other soluble ap.lip.p.oteins. During the course of p.imate evolution, the gene for this ap.lip.p.otein was dup.icated. p.omp.ed by our observation that the two resulting genes encode two distinct forms of ap.C-I in great ap.s, we have reviewed both the genomic and p.oteomic data to examine what changes have occurred during the course of p.imate evolution. We have found data showing that one of the dup.icated genes, known to be a p.eudogene in humans, was also a p.eudogene in Denisovans and Neandertals. Using genomic and p.oteomic data for p.imates, we will p.ovide in this review evidence that the dup.ication took p.ace after the divergence of New World monkeys from the human lineage and that the formation of the p.eudogene took p.ace after the divergence of the bonobos and chimp.nzees from the human lineage.

关键词： mass sp.ctrometry ap.C-ia ap.C-IB ap.s Old World monkeys New World monkeys

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Oral administration of S-nitroso-N-acetylcysteine p.events the onset of non alcoholic fatty liver disease in rats

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World Journal of Gastroenterology 2006年第12期12卷 1905-1911页

作者： Claudia p.S de Oliveira Fernanda I Simp.icio Vicencia MR de Lima Katia Yuahasi Fabio p.Lop.sso Venancio AF Alves Dulcinéia Sp.Abdalla Flair J Carrilho Francisco RM Laurindo Marcelo G de Oliveira University of Sāo p.ulo School of Medicine Department of Gastroenterology Saoo Paulo SP Brazil School of Medicine Department of Pathology Sāo Paulo SP Brazil University of So p.ulo Medical School Heart Institute InCor Sāo Paulo SP Brazil University of Sāo p.ulo School of Pharmaceutical Sciences Department of Clinical and Toxicological Analysis Sao Paulo SP Brazil State University of CamDinas. Chemistry Dep.rtment. Camp.nas. SE Brazil

AIM： To evaluate the p.tential of S-nitroso-N-acetylcysteine （SNAC） in inhibition of lip.d p.roxidation and the effect of oral SNAC administration in the p.evention of nonalcoholic fatty liver disease （NAFLD） in an animal model.METHODS： NAFLD was induced in Wistar male rats by choline-deficient diet for 4 wk. SNAC-treated animals （n=6）（1.4 mg/kg/day of SNAC, orally） were comp.red to 2 control group.： one （n=6） received p.S solution and the other （n=6） received NAC solution （7 mg/kg/d）. Histological variables were semiquantitated with resp.ct to macro and microvacuolar fat changes, its zonal distribution, foci of necrosis, p.rtal and p.rivenular fibrosis, and inflammatory infiltrate with zonal distribution. LOOHs from samp.es of liver homogenates were quantified by Hp.C. Nitrate levels in p.asma of p.rtal vein were assessed by chemiluminescence. Aqueous low-density lip.p.otein （LDL） susp.nsions （200 p. p.otein/mL） were incubated with CuCl2 （300 μmol/L） in the absence and p.esence of SNAC （300 μmol/L） for 15 h at 37 ℃ Extent of LDL oxidation was assessed by fluorimetry. Linoleic acid （LA）（18.8 μmol/L） oxidation was induced by soybean lip.xygenase （SLO）（0.056 μmol/L） at 37 ℃ in the p.esence and absence of N-acetylcysteine （NAC） and SNAC （56 and 560 p.ol/L） and monitored at 234 nm. RESULTS： Animals in the control group.develop.d moderate macro and microvesicular fatty changes in p.rip.rtal area. SNAC-treated animals disp.ayed only discrete histological alterations with absence of fatty changes and did not develop.liver steatosis. The absence of NAFLD in the SNAC-treated group.was p.sitively correlated with a decrease in the concentration of LOOH in liver homogenate, comp.red to the control group.（0.7±0.2 nmol/mg vs 3.2±0.4 nmol/mg p.otein, resp.ctively, p.0.05）, while serum levels of aminotransferases were unaltered. The ability of SNAC in p.eventing lip.d p.roxidation was confirmed in in vitro exp.riments using LA and LDL as model substrates. CONCLUSION： Oral

关键词： Nitric oxide S-nitroso-N-acetylcysteine Oxidative stress Nonalcoholic fatty liver disease

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Measurement of circulating levels of VEGF-A,-C,and -D and their recep.ors,VEGFR-1 and -2 in gastric adenocarcinoma

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World Journal of Gastroenterology 2008年第24期14卷 3879-3883页

作者： Mansour S Al-Moundhri A Al-Shukaili M Al-Nabhani B Al-Bahrani ia Burney A Rizivi SS Ganguly Medical Oncology Unit Department of MedicineCollege of Medicine and Health SciencesSultan Qaboos University Dep.rtment of Microbiology and Immunology (SQU) National Cancer Institute Royal Hospital Dep.rtment of Ep.demiology and Medical Statistics (SQU)

AIM: To analyze the serum levels and p.ognostic significance of vascular endothelial growth factor (VEGF) -A,-C,and -D,and their recep.ors,VEGFR-1 and -2 in gastric adenocarcinomas. METHODS: The serum levels of VEGF family members were measured in 76 control subjects and 76 p.tients with gastric adenocarcinoma using an enzyme-linked immunosorbent assay (ELISA). These measurements were correlated with clinco-p.thological features and survival rates. RESULTS: The serum levels of VEGF-A and its recep.or,VEGFR-1,were signifi cantly higher in p.tients with gastric cancer than in healthy donors (t = 2.3,p.= 0.02 and t = 4.2,p.p.ctively). In contrast,the serum levels of VEGF-D were signif icantly higher in control subjects than in p.tients (t = 2.9,p.= 0.004). There was no significant difference in serum levels of VEGF-C and VEGFR-2 between p.tients and controls. VEGF-C was associated with advanced tumor stage and p.esence of metastasis. VEGFR-1 was associated with metastasis,advanced overall stage,tumor differentiation and survival. VEGFR-2 levels were associated with p.or tumor differentiation. There was no significant p.ognostic value for any of the VEGF family members or their recep.ors excep. for VEGFR-1 where high levels were associated with a p.or overall survival. CONCLUSION: Serum VEGF levels vary significantly in the same cohort of p.tients with variable clinico-p.thological features and p.ognostic values. The simultaneous measurement of VEGF recep.ors levels in sera may overcome the limitations of a single biomarker assay.

关键词： Gastric cancer Serum Vascular endothelialgrowth factor Oman

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The influence of chemical comp.sition on models of Typ. ia sup.rnovae

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Frontiers of p.ysics 2013年第2期8卷 168-188页

作者： Alan C. Calder Brendan K. Krueger Aaron p. Jackson Dean M. Townsley Dep.rtment of p.ysics Astronomy The State University of New York - Stony Brook Stony BrookUSA NY 11794 New York Center for Comp.tational Sciences The State University of New York - Stony Brook Stony BrookUSA NY 11794 National Research Council Research Associateship.p.ogram and Laboratories for Comp.tational p.ysics and Fluid Dynamics Naval Research Laboratory WashingtonUSA DC 20375 Dep.rtment of p.ysics and Astronomy The University of Alabama TuscaloosaUSA AL 35487

Typ. ia sup.rnovae are bright stellar exp.osions distinguished by standardizable light curves that allow for their use as distance indicators for cosmological studies. Desp.te the highly successful use of these events in this cap.city, many fundamental questions remain. Contemp.rary research inves- tigates how p.op.rties of the p.ogenitor system that follow from the host galaxy such as comp.sition and age influence the brightness of an event with the goal of better understanding and assessing the intrinsic scatter in the brightness. We p.ovide an overview of these sup.rnovae and p.op.sed p.ogenitor systems, all of which involve one or more comp.ct stars known as white dwarfs. We describe contemp.rary research investigating how the comp.sition and structure of the p.ogenitor white dwarf systematically influences the exp.osion outcome assuming the p.ogenitor is a single white dwarf that has gained mass from a comp.nion. We p.esent results illustrating some of these systematic effects from our research.

关键词： hydrodynamics nuclear reactions nucleosynthesis abundances stars: sup.rnovae:general stars: white dwarfs

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