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Traversable braneworld wormholes supported by astrophysical observations

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Frontiers of physics 2018年第1期13卷 109-118页

作者： Deng Wang xin-he meng Theoretical Physics Division Chern Institute of Mathematics Nankai University Tianjin 300071 China Department of Physics Nankai University Tianjin 300071 China

In this study, we investigate the characteristics and properties of a traversable wormhole constrained by the current astrophysical observations in the framework of modified theories of gravity （MOG）. As a concrete case, we study traversable wormhole space-time configurations in the Dvali-Gabadadze- Porrati （DGP） braneworld scenario, which are supported by the effects of the gravity leakage of extra dimensions. We find that the wormhole space-time structure will open in terms of the 2o confidence level when we utilize the joint constraints supernovae （SNe） Ia ＋ observational Hubble parameter data （OHD）＋ Planck ＋ gravitational wave （GW） and z 〈 0.2874. Furthermore, we obtain several model-independent conclusions, such as （i） the exotic matter threading the wormholes can be divided into four classes during the evolutionary processes of the universe based on various energy conditions; （ii） we can offer a strict restriction to the local wormhole space-time structure by using the current astrophysical observations; and （iii） we can clearly identify a physical gravitational resource for the wormholes supported by astrophysical observations, namely the dark energy components of the universe or equivalent space-time curvature effects from MOG. Moreover, we find that the strong energy condition is always violated at low redshifts.

关键词： braneworld model traversable wormholes astrophysical observations

Restoring cosmological concordance with axion-like early dark energy and dark matter characterized by a constant equation of state?

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Communications in Theoretical Physics 2024年第7期76卷 74-82页

作者： Yan-Hong Yao xin-he meng School of Physics and Astronomy Sun Yatsen University 2 Daxue RoadTangjiaZhuhaiChina School of Physics Nankai University 94 Weijin RoadNankaiTianjinChina

The Hubble tension persists as a challenge in *** early dark energy(EDE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbating other tensions,such as the S_(8)*** that a negative dark matter(DM)equation of state(EoS)parameter is conducive to reduce the value of the σ_(8)parameter,we extend the axion-like EDE model in this paper by replacing the cold dark matter(CDM)with DM characterized by a constant EoS w_(dm)(referred to as WDM hereafter).We then impose constraints on this axion-like EDE extension model,along with three other models:the axion-like EDE model,ΛWDM,and Λ*** constraints are derived from a comprehensive analysis incorporating data from the Planck 2018 cosmic microwave background,baryon acoustic oscillations,and the Pantheon compilation,as well as a prior on H_(0)(i.e.H_(0)=73.04±1.04,based on the latest local measurement by Riess et al)and a Gaussianized prior on S_(8)(i.e.S_(8)=0.766±0.017,determined through the joint analysis of KID1000+BOSS+2dLenS).We find that although the new model maintains the ability to alleviate the Hubble tension to~1.4σ,it still exacerbates the S_(8)tension to a level similar to that of the axion-like EDE model.

关键词： Hubble tension early dark energy noncold dark matter S8 tension

Dark Energy Phenomenon from Backreaction Effect

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Communications in Theoretical Physics 2019年第9期71卷 1109-1114页

作者： Yan-Hong Yao xin-he meng Department of Physics Nankai University

In this paper, we interpret the dark energy phenomenon as an averaged effect caused by small scale inhomogeneities of the universe with the use of the spatial averaged approach of Buchert. Two models are considered here,one of which assumes that the backreaction term QD and the averaged spatial Ricci scalar (R)D obey the scaling laws of the volume scale factor a D at adequately late times, and the other one adopts the ansatz that the backreaction term QD is a constant in the recent universe. Thanks to the effective geometry introduced by Larena et al. in their previous work,we confront these two backreaction models with latest type Ia supernova and Hubble parameter observations, coming out with the results that the constant backreaction model is slightly favoured over the other model and the best fitting backreaction term in the scaling backreaction model behaves almost like a constant. Also, the numerical results show that the constant backreaction model predicts a smaller expansion rate and decelerated expansion rate than the other model does at redshifts higher than about 1, and both backreaction terms begin to accelerate the universe at a redshift around 0.5.

关键词： cosmological model dark energy cosmological backreaction effect

A Pressure Parametric Dark Energy Model

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Communications in Theoretical Physics 2018年第12期69卷 713-720页

作者： Jun-Chao Wang xin-he meng Department of Physics Nankai University

In this paper, we propose a new pressure parametric model of the total cosmos energy components in a spatially flat Friedmann-Robertson-Walker(FRW) universe and then reconstruct the model into quintessence and phantom scenarios, respectively. By constraining with the datasets of the type Ia supernova(SNe Ia), the baryon acoustic oscillation(BAO) and the observational Hubble parameter data(OHD), we find that ?_(m0)=0.270_(-0.034)^(+0.039) at the 1σ level and our universe slightly biases towards quintessence behavior. Then we use two diagnostics including Om(a) diagnostic and statefinder to discriminate our model from the cosmology constant cold dark matter(ΛCDM)model. From Om(a) diagnostic, we find that our model has a relatively large deviation from the ΛCDM model at high redshifts and gradually approaches the ΛCDM model at low redshifts and in the future evolution, but they can be easily differentiated from each other at the 1σ level all along. By the statefinder, we find that both of quintessence case and phantom case can be well distinguished from the ΛCDM model and will gradually deviate from each other. Finally,we discuss the fate of universe evolution(named the rip analysis) for the phantom case of our model and find that the universe will run into a little rip stage.

关键词： dark energy model quintessence phantom Om diagnostic statefinder the rip

Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di Zhang Pengfei Lv Wei Qin xin he Yuanhua he Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： xin LI Yibo ZHOU Tao ZHAO xingjian he Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

HMGB1 increases radiosensitivity by interacting with HDAC1

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中华放射医学与防护杂志 2015年第1期35卷 8-14页

作者： he xin meng Qinghui meng Aimin Liu Qiang Wang Haichao Fan Saijun hexin mengQinghui mengAimin LiuQiang WangHaichao FanSaijun 100092 Tianjin Key laboratory of Radiation Medicineand Nuclear Medicine Institute of Radiation Medicine ChineseAcademy of Medical Sciences China

ObjectiveTo study the nuclear protein association of high-mobility group box-1(HMGB1) and histone deacetylase 1(HDAC1), and the effect of interaction on radiosensitivity in human breast cancer cells.MethodsThe protein-protein interaction was determined by immunoprecipitation-Western blot and glutathione-S-transferase capture assays. Cell growth was examined by MTT (methyl thiazolyl tetrazolium)assay and clonogenic assay. Histone deacetylase activity was analyzed by histone deacetylase assay.ResultsA significant increase of HMGB1 protein and radiosensitivity was observed in MDA-MB-231 and MDA-MB-468 cells transfected with a pCMV-Tag2B expression vector carrying with a full-length of HMGB1 cDNA. HMGB1 binding to HDAC1 was demonstrated as GST(glutathione S-transferase)-pull down and immunoprecipitation Western blot assay, and the association was elevated by irradiation. An LXCXE motif was required for the HMGB1-HADC1 interaction and HMGB1 radiosensitization. A significant difference of IC 50 value was observed, for example, 1.8 and 2.2 Gy(wtHMGB1 transfectants, P0.05), both compared with 3.9 and 4.1 Gy(pCMV-Tag2B transfectants) in MDA-MB-231 and MDA-MB-468 cells, respectively. A specific HDAC1 inhibitor trichostatin A markedly reduced the HMGB1-mediated radiosensitivity, 0.5 Gy in the presence of trichostatin A versus 1.8 Gy in absence of trichostatin A in MDA-MB-231 transfectants, 1.2 Gy (with trichostatin A) versus 2.2 Gy (without trichostatin A) in MDA-MB-468 transfectants, Phese cells with antibodies to HMGB1, and this activity was abolished by the histone trichostatin A. ConclusionsThese results suggest a previous unanticipated role for HDAC1 in modification of HMGB1-mediated radiosensitivity by its direct interaction with HMGB1.

关键词：临床医学诊断放射医学 HMGB1

Bilevel Optimal Scheduling of Island Integrated Energy System Considering Multifactor Pricing

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Energy Engineering 2025年第1期122卷 349-378页

作者： xin Zhang Mingming Yao Daiwen he Jihong Zhang Peihong Yang Xiaoming Zhang School of Automation and Electrical Engineering Inner Mongolia University of Science and TechnologyBaotou014010China

In this paper,a bilevel optimization model of an integrated energy operator(IEO)–load aggregator(LA)is constructed to address the coordinate optimization challenge of multiple stakeholder island integrated energy system(IIES).The upper level represents the integrated energy operator,and the lower level is the electricity-heatgas load *** to the benefit conflict between the upper and lower levels of the IIES,a dynamic pricing mechanism for coordinating the interests of the upper and lower levels is proposed,combined with factors such as the carbon emissions of the IIES,as well as the lower load interruption *** price of selling energy can be dynamically adjusted to the lower LA in the mechanism,according to the information on carbon emissions and load interruption *** benefits and win-win situations are achieved between the upper and lower ***,CPLEX is used to iteratively solve the bilevel optimization *** optimal solution is selected according to the joint optimal discrimination *** results indicate that the sourceload coordinate operation can reduce the upper and lower operation *** the proposed pricingmechanism,the carbon emissions and load interruption power of IEO-LA are reduced by 9.78%and 70.19%,respectively,and the capture power of the carbon capture equipment is improved by 36.24%.The validity of the proposed model and method is verified.

关键词： Bilevel optimal scheduling load aggregator integrated energy operator carbon emission dynamic pricing mechanism

Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating B7H3

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Oncology Research 2025年第1期33卷 103-121页

作者： YAN LU KANG WANG YUANHONG PENG meng CheN LIN ZHONG LUJI HUANG FU CheNG xinDAN SheNG xin YANG MANZHAO OUYANG GEORGE A.CALIN ZHIWEI he China-America Cancer Research Institute Guangdong Medical UniversityDongguan523808China GCP Center Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China Department of Gastrointestinal Surgery Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou510080China Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Department of Oncology Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China

Background:Immune checkpoint inhibitors play an important role in the treatment of solid tumors,but the currently used immune checkpoint inhibitors targeting programmed cell death-1(PD-1),programmed cell death ligand-1(PD-L1),and cytotoxic T-lymphocyte antigen-4(CTLA-4)show limited clinical efficacy in many breast cancers.B7H3 has been widely reported as an immunosuppressive molecule,but its immunological function in breast cancer patients remains ***:We analyzed the expression of B7H3 in breast cancer samples using data from the Cancer Genome Atlas Program(TCGA)and the Gene Expression Omnibus(GEO)*** were selected using the TarBase,miRTarBase,and miRBase *** regulatory role of the microRNA hsa-miR-214-3p on B7H3 was investigated through dual-luciferase reporter assays,which identified the specific action sites of *** expression levels of B7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR(qPCR).In vitro experiments were performed to observe the effects of modulating the expression of B7H3 or hsa-miR-214-3p on breast cancer cell proliferation and ***,the regulatory impact of hsa-miR-214-3p on B7H3 was ***-linked immunosorbent assays(ELISA)and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells(PBMCs)on immune cells and associated ***:In breast cancer tissues,the expression level of B7H3 is inversely correlated with that of hsa-miR-214-3p,as well as with the regulatory effects on breast cancercell ***-miR-214-3p was found to inhibit breast cancer cell growth by downregulating ***,our research identified,for the first time,two binding sites for hsa-miR-214-3p on the 3’UTR of B7H3,both of which exert similar effects ***-culture experiments revealed that hsamiR-214-3p

关键词： Breast cancer B7H3 Hsa-miR-214-3p Immunotherapy