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Current status and prospects of basic research and clinical application of mesenchymal stem cells in acute respiratory distress syndrome

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World Journal of Stem Cells 2023年第4期15卷 150-164页

作者： Tian-yu Liang Li-Hai Lu Si-yu Tang zi-hao Zheng Kai Shi Jing-Quan Liu Emergency and Critical Care Center Intensive Care UnitZhejiang Provincial People's Hospital(Affiliated People's HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina Fourth School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina The Second School of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Respiratory Medicine The Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015Zhejiang ProvinceChina

Acute respiratory distress syndrome(ARDS)is a common and clinically devastating disease that causes respiratory *** and mortality of patients in intensive care units are stubbornly high,and various complications severely affect the quality of life of *** pathophysiology of ARDS includes increased alveolar–capillary membrane permeability,an influx of protein-rich pulmonary edema fluid,and surfactant dysfunction leading to severe *** present,the main treatment for ARDS is mechanical treatment combined with diuretics to reduce pulmonary edema,which primarily improves symptoms,but the prognosis of patients with ARDS is still very *** stem cells(MSCs)are stromal cells that possess the capacity to self-renew and also exhibit multilineage *** can be isolated from a variety of tissues,such as the umbilical cord,endometrial polyps,menstrual blood,bone marrow,and adipose *** have confirmed the critical healing and immunomodulatory properties of MSCs in the treatment of a variety of ***,the potential of stem cells in treating ARDS has been explored via basic research and clinical *** efficacy of MSCs has been shown in a variety of in vivo models of ARDS,reducing bacterial pneumonia and ischemia-reperfusion injury while promoting the repair of ventilator-induced lung *** article reviews the current basic research findings and clinical applications of MSCs in the treatment of ARDS in order to emphasize the clinical prospects of MSCs.

关键词： Acute respiratory distress syndrome Mesenchymal stem cells Pulmonary edema Inflammatory response Tissue repair Pulmonary fibrosis

Martian Thermosphere Response to Solar Flares:MAVEN NGIMS Observations

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Research in Astronomy and Astrophysics 2023年第5期23卷 190-197页

作者： zi-Chuan Li yu-Tian Cao National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-Sen UniversityZhuhai 519082China

The solar flare is a sudden eruptive solar phenomenon with significant enhancements in solar X-ray and Extreme Ultraviolet radiations,resulting in large amounts of energy being injected into the planetary *** studies have been extensively presented to analyze the effect of extremely large flares on the Martian upper atmosphere,but the general features of the Martian thermospheric response to flares are still poorly *** this work,we select 12 intense solar flares that occurred between 2015 and 2017 and investigate the densities and compositional variations of the dayside Martian thermosphere to these flares with the aid of the measurements made by the Mars Atmosphere and Volatile *** statistical studies indicate that the responses of the Martian thermosphere to flares are complicated that both the class of the flare and the wavelength of the enhanced radiation may have prominent influences on the thermal expansion of the atmosphere and the atmospheric photochemical reactions.

关键词： Sun flares-planets and satellites atmospheres-planets and satellites individual(Mars)

On the variable timing behavior of PSR B0540-69:an almost excellent example to study the pulsar braking mechanism

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Research in Astronomy and Astrophysics 2016年第5期16卷 81-86页

作者： Fei-Fei Kou zi-Wei Ou hao Tong Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

PSR B0540-69 has a braking index measurement in its persistent state： n = 2.129± 0.012. Recently, it has been reported to have changes in its spin-down state： a sudden 36% increase in the spin- down rate. Combining the persistent state braking index measurement with different spin-down states, PSR B0540-69 is more powerful than intermittent pulsars in constraining pulsar spin-down models. The pulsar wind model is applied to explain the variable timing behavior of PSR B0540-69. The braking index of PSR B0540-69 in its persistent state results from the combined effect of magnetic dipole radiation and particle wind. The particle density reflects the magnetospheric activity in real-time and may be responsible for the changing spin-down behavior. Corresponding to the 36% increase in the spin-down rate of PSR B0540-69, the relative increase in the particle density is 88% in the vacuum gap model. The braking index calculated with the model in the new state is n = 1.79. Future observations that measure the braking index of PSR B0540-69 in the new spin-down state will be very powerful in distinguishing between different pulsar spin-down models and different particle acceleration models in the wind braking scenario. The variable timing behavior of PSR J 1846-0258 is also understandable in the pulsar wind model.

关键词： pulsars: general -- pulsars: individual (PSR B0540-69 PSR J 1846-0258) -- stars: neutron-- wind

Study on the reaming process of aluminum alloy 7050-T7451 under different cooling conditions

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Advances in Manufacturing 2022年第2期10卷 272-286页

作者： zi Ye Yong-Guo Wang Xin yu School of Mechatronics Engineering and Automation Shanghai UniversityShanghai 200444People's Republic of China

Aluminum alloy 7050 is widely used in the aeronautical ***,owing to their highly ductile property,chips created during high-speed machining cannot be naturally broken,and long continuous chips are unavoidably formed,impacting the machining stability and quality of the *** a smaller cutting allowance is required compared with conventional machining operations,the behavior of the chips during reaming operation may be more complex and different from those determined in previous ***,studying the characteristics of chip formation and hole quality during the reaming process is essential to improve the machinability of aluminum alloy *** this study,three different cooling conditions were applied to reaming aluminum alloy 7050-T7451 with polycrystalline diamond(PCD)*** finite element models(FEMs)were established to simulate the chip *** macro-and micro-morphologies of chips under the three cooling conditions were compared to analyze the chip *** diameter,surface roughness,and micro-morphologies of the reamed holes were also analyzed to evaluate the hole *** results showed that the chip morphology was strongly influenced by the cutting parameters and cooling *** was found that the desired chip morphologies satisfactory geometrical accuracy and surface quality during the reaming of aluminum alloy 7050-T7451 could be achieved using internal cooling at a spindle speed of 8000 r/min and a feed rate of 0.0l mm/*** study also demonstrates the feasibility of an internal cooling strategy for breaking chips when reaming aluminum alloy 7050-T7451,which opens new possibilities for improving the chip-snarling that occurs during hole machining.

关键词： Chip morphology Hole quality Cooling conditions Reaming Aluminum alloy 7050-T7451 Finite element model(FEM)

Synthesis of TiO2@ZnIn2S4 hollow nanospheres with enhanced photocatalytic hydrogen evolution

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Rare Metals 2019年第5期38卷 420-427页

作者： He Li zi-hao Chen Lei Zhao Gui-Dong Yang XJTU-Oxford International Joint Laboratory for Catalysis School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China School of Civil Engineering and Architecture Xinxiang UniversityXinxiang 453003China

In this work,we designed and prepared the novel TiO2@ZnIn2 S4 nano-sized hollow structure via templating method assisted by hydrothermal synthesis *** unique hollow structure and type-II heterojunction between TiO2 hollow nanospheres and ZnIn2 S4 nanosheet can provide enough interior cavities and transfer paths for the light absorption and charge quick *** crystal structure,morphology and charges separation property were *** characterization results show that the hollow-structured Ti O2@ZnIn2 S4 was successfully prepared,and the optimal sample exhibited excellent photocatalytic hydrogen generation compared with TiO2/ZnIn2 S4 cluster exceeding by a factor of 1.1 under overall light ***,the detailed mechanism of the photocatalytic H2 evolution and charge carrier migration for the as-prepared TiO2@ZnIn2 S4 hollow nanosphere was also studied.

关键词： TiO2 ZnIn2S4 Photocatalysis Hydrogen evolution Hollow

Kinetics of bainite-to-austenite transformation during continuous reheating in low carbon microalloyed steel

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International Journal of Minerals,Metallurgy and Materials 2013年第5期20卷 427-432页

作者： Ming Chang hao yu School of Materials Science and Engineering University of Science and Technology Beijing

A dilatometer was used to study the kinetics of bainite-to-austenite transformation in low carbon microalloyed steel with the initial microstructure of bainite during the continuous reheating process. The bainite-to-austenite trans- formation was observed to take place in two steps at low heating rate. The first step is the dissolution of bainite, and the second one is the remaining bainite-to-austenite transformation controlled by a dissolution process. The calculation result of the kinetics of austenite formation shows that the two steps occur by diffusion at low heating rate. However, at high heating rate the bainite-to-austenite transformation occurs in a single step, and the process is mainly dominated by shear. The growth rate of austenite reaches the maximum at about 835℃ at different heating rates and the growth rate of austenite as a function of temperature increases with the increase in heating rate.

关键词： low carbon steel microalloying bainite austenite phase transformations reheating kinetics

Probabilistic modeling of scenes using object frames

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Science China(Information Sciences) 2015年第3期58卷 119-131页

作者： SU hao yu AdamsWei School of Mathematics Beihang University Department of Computer Science Stanford University Language Technologies Institute Carnegie Mellon University

In this paper,we propose a probabilistic scene model using object frames,each of which is a group of co-occurring objects with fixed spatial *** contrast to standard co-occurrence models,which mostly explore the pairwise co-existence of objects,the proposed model captures the spatial relationship among groups of *** information is closely tied to the semantics of the underlying scenes,which allows us to perform object detection and scene recognition in a unified *** proposed probabilistic model has two major *** first models the dependencies between object frames and objects by adopting the Latent Dirichlet Allocation model for text *** second component characterizes the dependencies between object frames and scenes by establishing a mapping between global image features and object frame *** results show that the induced object frames are both semantically meaningful and spatially *** addition,our model significantly improves the performance of object recognition and scene retrieval.

关键词： Bayes network scene understanding object frame probabilistic model

Semi-theoretical analyses of the concrete plate perforated by a rigid projectile

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Acta Mechanica Sinica 2012年第6期28卷 1630-1643页

作者： hao Wu Qin Fang Ya-Dong Zhang zi-Ming Gong Institute of Structural Mechanics China Academy of Engineering Physics College of Defense Engineering PLA University of Science and Technology

Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic per- formances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistance coefficients, dimensionless formulae are proposed for depth of penetra- tion （DOP）, perforation limit thickness, ballistic limit veloc- ity, residual velocity and perforation ratio, with the projec- tile nosed geometries and projectile-target interfacial fric- tion taken into account. Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets, a new expression is obtained for target strength parameter. By comparisons between the re- sults of the proposed formulae and existing empirical formu- lae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets, the validations of the proposed formulae are verified. It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters. The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/（nS）. The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity. The variation range of the perforation ratio is 1-3.5 for concrete targets.

关键词： Projectile Concrete Depth of penetration Perforation limit thickness Ballistic limit velocity Resid-ual velocity

On-line spheroidization process of medium-carbon low-alloyed cold heading steel

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International Journal of Minerals,Metallurgy and Materials 2014年第1期21卷 26-35页

作者： yu Fu hao yu Pan Tao School of Materials Science and Engineering University of Science and Technology Beijing

Conventionally manufactured 35CrMo cold heading steel must undergo spheroidization annealing before the cold heading process In this paper, different types of deformation processes with various controlled cooling periods were operated to achieve on-line spheroidal cementite using the Gleeble-3500 simulation technique. According to the measured dynamic ferrite transformation temperature （Ad3）, the deformation could be divided into two types： low temperature deformation at 810 and 780℃; ＂deformation-induced ferrite transformation＂（DIFT） deformation at 750 and 720℃. Compared with the low temperature deformation, the DIFT deformation followed by accelerated cooling to 680℃ is beneficial for the formation of spheroidal cementite. Samples subjected to both the low-temperature deformation and DIFT deformation can obtain granular bainite by accelerated cooling to 640℃; the latter may contribute to the formation of a fine dispersion of secondary constituents. Granular bainite can transform into globular pearlite rapidly during subcritical annealing, and the more the disperse phase, the more homogeneously distributed globular cementite can be obtained.

关键词： steel heat treatment cold heading spheroidization globular cementite subcritical annealing