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A Generalization of a Theorem of Liao

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Acta Mathematica Sinica,English Series 2006年第1期22卷 207-210页

作者： Xiong ping DAI zuo Ling ZHOU Depatment of Mathematics Nanjing University Nanjing 210093 P. R. China Lingnan College of Zhongshan University Guangzhou 510275 P. R. China

Let X be a metrizable space and let φ：R× X → X be a continuous flow on X. For any given {φt}-invariant Borel probability measure, this paper presents a {φt}-invariant Borel subset of X satisfying the requirements of the classical ergodic theorem for the contiImous flow （X, {φt}）. The set is more restrictive than the ones in the literature, but it might be more useful and convenient, particularly for non-uniformly hyperbolic systems and skew-product flows.

关键词： Ergodic theorem Liao theory

Spatial Distribution and Anisotropy of Energetic Particles Accelerated by Shock Waves: Focused Transport Model

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Chinese Physics Letters 2013年第1期30卷 235-238页

作者： zuo ping-Bing FENG Xue-Shang SIGMA Weather Group State Key Laboratory of Space WeatherCenter for Space Science and Applied ResearchChinese Academy of SciencesBeijing 100190

The focused transport equation(FTE)contains the necessary physics of shock acceleration but avoids the limitation of small pitch-angle anisotropy inherent in the cosmic ray transport *** present a focused transport model based on FTE to investigate the spatial distribution and anisotropy of energetic particles accelerated by shock waves from pickup *** is found that in the upstream of the shock,the accelerated particles are highly anisotropic,but in the downstream it is approximately *** intensity spike is formed across the *** simulation results are qualitatively consistent with the observations of the termination shock particles by two Voyager spacecraft in the vicinity of the termination shock.

关键词： equation. shock anisotropy

Abnormal chemical composition fluctuations in multi-principal-element alloys induced by simple cyclic deformation

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Journal of Materials Science & Technology 2022年第18期113卷 287-295页

作者： Mengyuan He Nan jia.Xiaochun Liu Yongfeng Shen Liang zuo Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Institute of Metals College of Materials Science and EngineeringChangsha University Of Science and TechnologyChangsha 410114China

High entropy alloys exhibit excellent combination of mechanical properties because of the unique com-position fluctuations,termed as‘concentration wave’.The concentration wave was closely related to mul-tiple aspects,including the fluctuation of local strain energy,local atomic environment,electronegativity,*** we report for the first time that the amplitude of the concentration wave can be mechani-cally tailored under cyclic deformation in a well-known Cantor ***-scale energy-dispersive X-ray spectroscopy(EDS)mapping reveals that cyclic deformation may dynamically induce the clustering of solute atoms with a size of 1-3 nm,thus resulting in a higher concentration wave *** con-centration wave promotes strong interactions between dislocations and local solute *** from the typical Taylor strengthening contribution due to the presence of isolated dislocations,the strength enhancement from the mechanically induced composition fluctuations was quantified to be as high as∼70 MPa,about one-third of the yield strength of the alloy without *** opens up a novel strategy of designing high strength alloys by tailoring solute configurations.

关键词： Cantor alloy Cyclic deformation Concentration wave EDS maps

Gut Microbiome Alterations in COVID-19

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Genomics, Proteomics & Bioinformatics 2021年第5期19卷 679-688页

作者： Tao zuo Xiaojia. Wu Weiping Wen ping Lan Guangdong Institute of Gastroenterology The Sixth Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhou 510655China Center for Fecal Microbiota Transplantation Research The Sixth Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhou 510655China Department of Colorectal Surgery The Sixth Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhou 510655China Department of Otorhinolaryngology Head and Neck SurgeryThe First Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhou 510080China Guangzhou Key Laboratory of Otorhinolaryngology Guangzhou 510080China Department of Otorhinolaryngology Head and Neck SurgeryThe Sixth Affiliated Hospital of Sun Yat-sen UniversitySun Yat-sen UniversityGuangzhou 510655China

Since the outset of the coronavirus disease 2019(COVID-19)pandemic,the gut microbiome in COVID-19 has garnered substantial interest,given its significant roles in human health and *** evidence is unveiling that the gut microbiome is broadly altered in COVID-19,including the bacterial microbiome,mycobiome,and ***,the gut microbial ecological network is significantly weakened and becomes sparse in patients with COVID-19,together with a decrease in gut microbiome *** the existence of severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2),the gut microbiome of patients with COVID-19 is also characterized by enrichment of opportunistic bacteria,fungi,and eukaryotic viruses,which are also associated with disease severity and ***,a multitude of symbiotic bacteria and bacteriophages are decreased in abundance in patients with *** gut microbiome features persist in a significant subset of patients with COVID-19 even after disease resolution,coinciding with‘long COVID’(also known as postacute sequelae of COVID-19).The broadly-altered gut microbiome is largely a consequence of SARS-CoV-2 infection and its downstream detrimental effects on the systemic host immunity and the gut *** impaired host immunity and distorted gut microbial ecology,particularly loss of low-abundance beneficial bacteria and blooms of opportunistic fungi including Candida,may hinder the reassembly of the gut microbiome post *** investigation is necessary to fully understand the role of the gut microbiome in host immunity against SARS-CoV-2 infection,as well as the long-term effect of COVID-19 on the gut microbiome in relation to the host health after the pandemic.

关键词： COVID-19 Gut Microbiome Immunity Infection

Regulation of the Macrophage Phenotype on Titanium Metal by Surface Modification

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Journal of Bionic Engineering 2022年第6期19卷 1625-1636页

作者： Shibing Xiong Xugang Lu Rui zuo ping Huang Bangcheng Yang Engineering Research Center in Biomaterials Sichuan UniversityChengdu610064China National Engineering Research Center for Biomaterials Chengdu610064China Sichuan Guojia.Biomaterials Co. LtdChengdu610064China Panzhihua University Panzhihua Int Res Inst Vanadium and TitaniumPanzhihua617000SichuanChina

The regulation of macrophage phenotype(M1/M2)is very important for tissue *** macrophage phenotypes could be affected by the physical and chemical parameters of implant *** aim of this study was to investigate the effects of surface modifications of titanium metals on macrophage *** medical pure titanium metals(PT-Ti)subjected to Anodic Oxidation(AO-Ti),Sand Blasting/acid etching(SLA-Ti)and Plasma-sprayed HA coating(HA coating-Ti)were used for regulating the phenotype of *** results showed that the Raw264.7 cells of AO-Ti groups had no obvious pseudopodia and could spread evenly in all *** levels of IL-1βand TNF-α,which belong to pro-inflammatory genes,expressed by the cells on AO-Ti groups were the lowest among all of the modified titanium ***,the levels of IL-10 and TGF-β,which belong to anti-inflammatory genes,expressed on AO-Ti groups were much higher than those on the other ***,the AO-Ti could regulate the expression of SOCS-1 and SOCS-3 to affect the active of NF-κB *** gene expression results of macrophages showed that the AO-Ti was more conductive to inhibit the expression of M1-related genes and promote the expression of M2-related genes in an inflammatory *** AO-Ti was more beneficial to tissue repair than other modified titanium *** results showed that the anodic oxidation is an effective method to regulate the phenotype of macrophages.

关键词： Titanium Dental implant Bionic surface modification Anti-inflammatory Macrophage phenotype

Large eddy simulation of the transient cavitating vortical flow in a jet pump with special emphasis on the unstable limited operation stage

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Journal of Hydrodynamics 2020年第2期32卷 345-360页

作者： Xin-ping Long Dan zuo Huai-yu Cheng Bin Ji Hubei Key Laboratory of Waterjet Theory and New Technology School of Power and Mechanical EngineeringWuhan UniversityWuhan430072China Key Laboratory of Transients in Hydraulic Machinery Ministry of EducationWuhan UniversityWuhan430072China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

This paper studies the unsteady three-dimensional cavitating turbulent flow in a jet ***,thefocus is on the unstable limited operation stage,and both the computational and experimental methods are *** the experiments,the distribution of the wall pressure,as well as the evolution of cavitation over time,are obtained for a jet *** is carried out using the large eddy simulation,combined with a mass transfer cavitation *** numerical results are compared with the experimental results,including the fundamental performances(the pressure ratio h and the efficiencyη),as well as the wall pressure *** the experimental and computational results indicate that the evolution of the cavitation over time in a jet pump is a quasi-periodic process during the unstable limited operation *** annular vortex cavitation inception,development and collapse predicted by the large eddy simulation agree fairly well with the experimental ***,the relationship between the cavitation and the vortex structure is discussed based on the numerical results,and it is shown that the development of the vortex structures in the jet pump is closely related to the evolution of the *** cavitation-vortex interaction is thoroughly analyzed based on the vorticity transport *** analysis reveals that the cavitation in a jet pump dramatically influences the distribution and the production of the *** process of the annular cavitation inception,development,and collapse involves a significant increase of the vorticity.

关键词： Cavitation jet pump large eddy simulation vortex structure vorticity transport equation

Role of ocean upper layer warm water in the rapid intensification of tropical cyclones: A case study of typhoon Rammasun(1409)

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Acta Oceanologica Sinica 2016年第3期35卷 63-68页

作者： SUN jia.zuo Juncheng LING Zheng YAN Yunwei Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai University Institute of Physical Oceanography Hohai University State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration

Rammasun intensified rapidly from tropical storm to super typhoon in the northern South China Sea（NSCS）before its landfall on Hainan Island. Analysis of observed data shows that the anomalous ocean upper layer warm water（WW） is important to the rapid intensification of Rammasun. During the period of Rammasun, sea surface temperature（SST） in the NSCS was much warmer than the climatological SST. The anomalous WW supplied more energy to Rammasun, resulting in its rapid intensification. Numerical simulations further confirm that the NSCS WW plays an important role in the rapid intensification of Rammasun. As the WW is removed, the intensification of Rammasun is only 25 h Pa, which is 58.1% of that in the original SST-forced run.

关键词： tropical cyclone Rammasun rapid intensification warm water sea surface temperature

Thermal performance of solar air collector with transparent honeycomb made of glass tube

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Science China(Technological Sciences) 2009年第8期52卷 2323-2329页

作者： ZHANG ZhiQiang zuo Ran LI ping SU Wenjia School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China

Transparent honeycomb structure with thin-walled glass tube as the honeycomb unit is designed and applied to a flat-plate solar air collector. Experiments are performed for solar collectors with six different honeycomb sizes. The emphasis is to study the effects of diameter and aspect ratio of the honeycomb unit on the transmittance and efficiency of the solar collector. It is shown that for the same diameter but different aspect ratios, there are large temperature differences between the collector’s exits; the smaller the aspect ratio, the larger the exit temperature, with a maximum difference of 10°C; for the same aspect ratio but different diameters, the temperature differences are small; the maximum temperature difference between the collectors with and without honeycombs is 12°C. A theoretical expression for the honeycomb transmittance is derived with a simplified method. The result shows that the honeycomb transmittance is only related with the aspect ratio and the materials’ optical properties but not the actual size of the honeycomb.

关键词： solar air collector transparent honeycomb transmittance thermal efficiency

Time-effect relationship of acupuncture on histopathology, ultrastructure, and neuroethology in the acute phase of cerebral hemorrhage

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Neural Regeneration Research 2019年第1期14卷 107-113页

作者： zuo-Wei Li Xiao-Nan Zheng ping Li Shandong University of Traditional Chinese Medicine Department of Acupuncture Affiliated Hospital of Tianjin Academy of Traditional Chinese Medicine Tianjin Third Central Hospital

Many clinical studies have addressed the treatment of acute cerebral hemorrhage using acupuncture. However, few studies have examined the relationship between time of acupuncture and curative effect on cerebral hemorrhage. By observing the effect of acupuncture on changes in histopathology, ultrastructure, and neuroethology in a cerebral hemorrhage model of rats, we have directly examined the time-effect relationship of acupuncture. The rat model of cerebral hemorrhage was produced by slowly injecting autologous blood to the right caudate nucleus. The experimental groups were: 3-, 9-, 24-, and 48-hour model groups; and 3-, 9-, 24-, and 48-hour acupuncture groups. The sham-operation group was used for comparison. Acupuncture was performed at the Neiguan(PC6) and Renzhong(DU26) acupoints, twice a day, 6 hours apart, for 5 consecutive days. Brain tissue changes were observed by light microscopy and transmission electron microscopy. Neuroethology was assessed using Bederson and Longa scores. Our results show that compared with the sham-operation and model groups, Bederson and Longa scores were lower in each acupuncture group, with visibly improved histopathology and brain tissue ultrastructure. Further, the results were better in the 3-and 9-hour acupuncture groups than the 24-and 48-hour acupuncture groups. Our findings show that acupuncture treatment can relieve pathological and ultrastructural deterioration and neurological impairment caused by the acute phase of cerebral hemorrhage, and may protect brain tissue during this period. In addition, earlier acupuncture intervention following cerebral hemorrhage(by 3 or 9 hours) is associated with a better treatment outcome.

关键词： nerve regeneration acupuncture acute phase cerebral hemorrhage time-effect ultrastructure function histopathology neuroethology brain injury neural regeneration