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Primordial black hole mass functions as a probe of cosmic origin

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： Yi-Fu Cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen xiao-han ma Bo Wang Wentao Luo Damien A.Easson Antonino marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via Enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce *** standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from *** demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic ***,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

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Effect of total lumbar disc replacement on the treatment of discogenic low lumbar pain： preliminary outcomes

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Chinese Medical Journal 2013年第8期126卷 1504-1508页

作者： LI Zhi-yu han xiao ma Sai TIAN Wei Department of Spine Surgery Beijing Jishuitan Hospital Beijing100035 China

Background Lumbar pedicle screw fixation and fusion are major procedures for treating discogenic low back pain （DLBP）. However, due to its advantages of preserving the segmental motion and biomechanical simulation, artificial total lumbar disc replacement （TDR） is increasingly popular. Methods From 2007 to 2010, 68 DLBP patients were enrolled. TDR were performed on 34 patients and the other 34 controls underwent the traditional fixation procedure. Qualitative and quantitative evaluations were followed including the changes in range of motion （ROM） and interpedicle height （IPH） at the posterior intervertebral body of operated level, in 6 and 12 months, and 3 years, postoperatively. Results Qualitative results showed satisfying improvement in the two groups after 6 and 12 months, respectively, and the inter-group differences were significant （P 〉0.05）. The results of ROM and IPH have shown significant differences between the TDR and spinal fusion groups （P 〈0.05）. Conclusion With similar clinical improvements as the traditional spinal fusion method, TDR offered significantly better ROM and intervertebral foramen ***.

关键词： total lumbar disc replacement, discogenic low lumbar pain, range of motion spinal fusion

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Knots and Polynomials

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Journal of mathematical Research and Exposition 2010年第2期30卷 257-264页

作者： You Fa han xiao Sha ma School of mathematics Liaoning Normal University Liaoning 116029 P. R. China

In this paper, we deal with some corresponding relations between knots and polynomials by using the basic properties of knot polynomials （such as, some special values of knot polynomials, the Arf invariant and derivative of knot polynomials）. We give necessary and sufficient conditions that a Laurent polynomial with integer coefficients, whose breadth is less than five, is the Jones polynomial of a certain knot.

关键词： knot Jones polynomial Laurent polynomial.

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A Secure Communicating While Jamming Approach for End-to-End Multi-Hop Wireless Communication Network

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Chinese Journal of Electronics 2024年第3期33卷 833-846页

作者： xiao ma Dan LI Liang WANG Weijia han Nan ZHAO School of Physics and Information Technology Shaanxi Normal University Beijing Aerospace Science and Industry Century Satellite Hi-tech Co. Ltd.Xi'an Branch School of Computer Science Shaanxi Normal University School of Telecommunications Engineering Xidian University

With the rapid development of wireless communications,cellular communication and distributed wireless network are fragile to eavesdropping due to distributed users and transparent ***,to adopt bigger transmit power at a given area to interfere potential eavesdroppers not only incurs huge energy waste but also may suppresses regular communication in this *** this end,we focus on secure communication in multi-hop wireless communication network,and propose two communicating while jamming schemes for secure communication in presence of potential eavesdroppers for the narrow band and broad band point-to-point(P2P) systems respectively with the aid of artificial noise transmitted by a chosen cooperative ***,to achieve the end-to-end(E2E) multi-hop secure communication,we devise the secure network topology discovering *** constructing a proper network topology with at least one proper node as the cooperative interferer in each hop,and then propose the secure transmission path planning scheme to find an E2E secure transmission route from source to destination,*** on the wireless open-access research platform demonstrate the feasibility of the proposed ***,simulations results validate that the proposed schemes can achieve better performance compared with existing methods in both the P2P communication case and E2E multi-hop communication network scenario.

关键词： Wireless communication Network topology Law Simulation Wireless networks Noise Spread spectrum communication

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Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan Meng Cai Wen-Hai ma xiao-Chuan Zhang Li-Hong han Yong-Hong Liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

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Random Raman Fiber Laser as a Liquid Refractive Index Sensor

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Photonic Sensors 2024年第1期14卷 13-22页

作者： Bing han Yuxi ma han WU Yong ZHAO College of Information Science and Engineering Northeastern UniversityShenyang 110819China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao 066004China College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China

In this paper,a new concept of forward-pumped random Raman fiber laser(RRFL)-based liquid refractive index sensing is proposed for the first *** liquid refractive index sensing,the flat fiber end immersed in the liquid can act as the point reflector for generating random fiber lasing and also as the sensing *** to the high sensitivity of the output power of the RRFL to the reflectivity provided by the point reflector in the ultralow reflectivity regime,the proposed RRFL is capable of achieving liquid refractive index sensing by measuring the random lasing output *** theoretically investigate the effects of the operating pump power and fiber length on the refractive index sensitivity for the proposed *** a proof-of-concept demonstration,we experimentally realize high-sensitivity half-open short-cavity RRFL-based liquid refractive index sensing with the maximum sensitivity and the sensing resolution of-39.88W/RIU and 2.5075×10^(-5) RIU,*** also experimentally verify that the refractive index sensitivity can be enhanced with the shorter fiber length of the *** work extends the application of the random fiber laser as a new platform for highly-sensitive refractive index sensing in chemical,biomedical,and environmental monitoring applications,etc.

关键词： Fiber optic sensors refractive index measurements fiber lasers Rayleigh scattering stimulated Raman scattering

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Progress in the treatment of advanced hepatocellular carcinoma with immune combination therapy

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 273-286页

作者： Di Pan Hao-Nan Liu Peng-Fei Qu xiao ma Lu-Yao ma xiao-xiao Chen Yu-Qin Wang xiao-Bing Qin Zheng-Xiang han Department of Oncology The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina Department of General Surgery The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

Advanced hepatocellular carcinoma(HCC)is a severe malignancy that poses a serious threat to human *** to challenges in early diagnosis,most patients lose the opportunity for radical treatment when ***,recent advancements in cancer immunotherapy provide new directions for the treatment of *** instance,monoclonal antibodies against immune check-point inhibitors(ICIs)such as programmed cell death protein 1/death ligand-1 inhibitors and cytotoxic t-lymphocyte associated antigen-4 significantly improved the prognosis of patients with ***,tumor cells can evade the immune system through various *** the rapid development of genetic engineering and molecular biology,various new immunotherapies have been used to treat HCC,including ICIs,chimeric antigen receptor T cells,engineered cytokines,and certain cancer *** review summarizes the current status,research progress,and future directions of different immunotherapy strategies in the treatment of HCC.

关键词： Hepatocellular carcinoma Immunotherapies Immune checkpoint inhibitor Clinical efficacy Adverse reactions

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Composite laminar membranes for electricity generation from water evaporation

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Nano Research 2024年第1期17卷 307-311页

作者： xiao Wang Gang Yuan han Zhou Yu Jiang Shuo Wang Jiaojiao ma Chongyang Yang Sheng Hu State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy materials of Fujian Province(IKKEM) Xiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

Harvesting clean energy from water evaporation has been extensively investigated due to its *** achieve high efficiency,energy conversion materials should contain multiple features which are difficult to be simultaneously obtained from single-component *** we use composite laminar membranes assembled by nanosheets of graphene oxide and mica,and find a sustained power density induced by water evaporation that is two orders of magnitude larger than that from membranes made by either of the *** power output is attributed to selective proton transport driven by water evaporation through the interlayer nanochannels in the *** process relies on the synergistic effects from negatively charged and hydrophilic mica surfaces that are important for proton selectivity and water transport,and the tunable electrical conductivity of graphene oxide that provides optimized internal *** demonstrated composite membranes offer a strategy of enhancing power generation by combining the advantages from each of their components.

关键词： graphene oxide mica water evaporation electrical double layer surface charge ion selectivity

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A new method for evaluating wedges of steel plates and strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1719-1735页

作者： xiao-bao ma xiao-xin ma Tao Wang Zhong-kai Ren Yu-cheng Ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina China National Heavy machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

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High-entropy oxide-supported platinum nanoparticles for efficient hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1537-1546页

作者： Ming-Yu Fan Jia-Jun Wang Jun Zhao Hong Zhang Tian-Yi ma xiao-Peng han Wen-Bin Hu School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Key Laboratory of Advanced Ceramics and Machining TechnologyTianjin UniversityTianjin300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China School of Science RMIT UniversityMelbourneVIC3000Australia

High-entropy oxides(HEOs)are a new class of single-phase structures with unique electronic and catalytic properties;therefore,it is worthwhile to explore their applications in *** this study,a Pt/(FeCoNiCrAl)_(3)O_(4)nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction(HER).Pt/(FeCoNiCrAl)_(3)O_(4)exhibited high HER activity with a low overpotential of 22 mV at10 ma·cm^(-2),outperforming other binary,ternary,and quaternary *** HER activity of Pt/(FeCoNiCrAl)_(3)O_(4)was higher than that of a commercial Pt/C with a significantly lower Pt *** catalyst exhibited good activity and long-term stability(60 h)in an electrolytic water-splitting *** good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the *** addition,the HEO substrate was more favorable for dispersing Pt particles,optimizing the electrochemical specific surface area,and significantly reducing the charge resistance of the *** study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.

关键词： High-entropy oxides Hydrogen evolution reaction Nanohybrid Water electrolysis

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