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Role of platelet-derived extracellular vesicles in traumatic brain injury-induced coagulopathy and inflammation

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Neural Regeneration Research 2022年第10期17卷 2102-2107页

作者： Liang Liu quan-Jun deng Department of Neurosurgery Tianjin Institute of NeurologyTianjin Medical University General HospitalTianjinChina

Extracellular vesicles are composed of fragments of exfoliated plasma membrane,organelles or nuclei and are released after cell activation,apoptosis or ***-derived extracellular vesicles are the most abundant type of extracellular vesicle in the blood of patients with traumatic brain *** laboratory and clinical evidence shows that platelet-derived extracellular vesicles play an important role in coagulopathy and inflammation after traumatic brain *** review discusses the recent progress of research on platelet-derived extracellular vesicles in coagulopathy and inflammation and the potential of platelet-derived extracellular vesicles as therapeutic targets for traumatic brain injury.

关键词： angiogenesis clotting factors coagulopathy delivery inflammation platelet-derived extracellular vesicles review target traumatic brain injury

C–C formation mediated by photoinduced electrons from crystallized carbon nitride nanobelts under visible light irradiation

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Journal of Energy Chemistry 2019年第3期28卷 152-161页

作者： Qiaohui jia Sufen Zhang quan Gu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education School of Chemistry and Chemical Engineering Shaanxi Normal University

Crystal structure and crystallinity of carbon nitride support, size and dispersity of active-metal nanoparticles(NPs), and surface engineering of composites have great roles in generation and separation of photogenerated charge carries and photocatalyzed organic reactions for the conversion of solar energy into chemical energy. Herein, we deposited well-dispersed Pd NPs with small size on crystallized carbon nitride(CN–C) to construct a Schottky-type Pd/CN–C hybrid for photocatalyzed Ullmann C–C homocoupling of aryl halides under visible light irradiation at room temperature. Compared to Pd NPs supported g-C_3N_4(Pd/g-C_3N_4), Pd/CN–C exhibits excellent visible light photocatalytic activity for Ullmann C–C coupling of aryl halides due to high crystallinity of CN–C support, high dispersion and smaller size of Pd NPs, and the interfacial heterojunction of Pd/CN–C. Upon visible light irradiation, more photogenerated electrons from CN–C flow across the Schottky junction to metallic Pd and trigger the Ullmann C–C coupling of aryl halides. The photogenerated holes on CN–C surface are captured by a protic solvent(such as EtOH). In the presence of base K_2CO_3, the solvent undergoes dissociation, dehydrogenation, and finally can be oxidized by captured photogenerated holes. Moreover, Pd/CN–C has general applicability for various substrates and shows excellent stability and reusability for more than nine cycles.

关键词： Crystallized carbon nitride Pd nanoparticles Photocatalyst C–C coupling Ullmann reaction

Reversible Plasticity Shape Memory Effect in SEBS/Crystallizable Paraffin: Influence of Paraffin Content

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Chinese Journal of Polymer Science 2022年第12期40卷 1697-1705,I0011页

作者： Shao-quan Zhao jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University Yiwu 322000China

Polymers with reversible plasticity shape memory effect(RPSME)have attracted considerable attention due to their simple programming and large ***,the exact mechanisms of RPSME are still not thoroughly *** this work,the RPSME of SEBS/crystallizable paraffin was investigated by comparatively analyzing the performances and microstructures of samples with different paraffin *** was found the shape fixing ratios(Rfs)of samples increased with the paraffin content,and interestingly,a significant improvement in Rf was observed when the paraffin content exceeded 60 wt%.Tensile test results showed that the deformation characteristics of samples changed from elastic to plastic as the paraffin content increased above 60 wt%.By exploring the crystallization behaviors of paraffin in various SEBS/paraffin samples,it was revealed that the microstructures of SEBS/paraffin were different when the paraffin content was below 50 wt%and above 60 wt%.In samples with low paraffin content(below 50 wt%),nearly all paraffin was co-crystallized with ethylene-co-butylene(EB)chains and its crystallization was severely restricted;while in samples with high paraffin content(above 60 wt%),“excess”paraffin appeared and this part of paraffin crystallized on the template of the EB/paraffin co-crystals,which might be responsible for the elastic-to-plastic transition and the sharp increase in *** on the above results,a possible structural model was proposed to explain the exact mechanism of RPSME in SEBS/paraffin.

关键词： Reversible plasticity shape memory effect Poly(styrene-b-(ethylene-co-butylene)-b-styrene) Crystallizable paraffin Paraffin content

Is hand sewing comparable with stapling for anastomotic leakage after esophagectomy? A meta-analysis

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World Journal of Gastroenterology 2014年第45期20卷 17218-17226页

作者： quan-Xing Liu jia-Xin Min Xu-Feng deng Ji-Gang Dai Department of Thoracic Surgery Xinqiao Hospital Third Military Medical University

AIM: To compare the outcome of hand sewing and stapling for anastomotic leakage after esophagectomy.

关键词： Anastomotic leakage Esophagectomy Hand-sewn sutures Mechanical sutures Meta-analysis

Assessing ecological vulnerability in western China based on Time-Integrated NDVI data

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Journal of Arid Land 2016年第4期8卷 533-545页

作者： JIN jia WANG quan Joint Research Center of Drylands Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan

Arid and semi-arid areas are the most vulnerable regions to climate change. Clear understanding of the effects of climate change on ecosystems in arid and semi-arid regions and the ecosystem vulnerability is important for ecosystem management under the background of climate change. In this study, we conducted a vulnerability assessment on various ecosystems from 1982 to 2013 in western China with large areas of arid and semi-arid lands based on the Time-Integrated Normalized Difference Vegetation Index （TINDVI） data and climate data. The results indicated that grasslands were the most vulnerable ecosystem to climate change in western China, especially for those in Tibetan Plateau. Croplands in oases were not vulnerable to climate change compared to rain-fed croplands in semi-arid regions （e.g. Gansu and Inner Mongolia）, which was attributed to the well-developed drip irrigation technology in oases. Desert and Gobi ecosystems were slightly vulnerable to climate change during the past several decades. The assessment results, as revealed in this study, can provide a reference for taking appropriate actions to protect the ecosystems in western China.

关键词： vulnerability sensitivity adaptability climate change Time-Integrated Normalized Difference VegetationIndex (TINDVI) western China

Asymptotic Preserving Schemes for Semiconductor Boltzmann Equation in the Diffusive Regime

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Numerical Mathematics(Theory,Methods and Applications) 2012年第2期5卷 278-296页

作者： jia deng Department of Mathematical Sciences Tsinghua UniversityBeijing 100084P.R.China

As is known,the numerical stiffness arising from the small mean free path is one of the main difficulties in the kinetic *** this paper,we derive both the split and the unsplit schemes for the linear semiconductor Boltzmann equation with a diffusive *** the two schemes,the anisotropic collision operator is realized by the“BGK”-penalty method,which is proposed by Filbet and Jin[*** and ***,***.229(20),7625-7648,2010]for the kinetic equations and the related problems having stiff *** to the numerical results,both of the schemes are shown to be uniformly convergent and ***,numerical evidences suggest that the unsplit scheme has a better numerical stability than the split scheme.

关键词： linear semiconductor Boltzmann equation drift-diffusion limit diffusive relaxation system “BGK”-penalty method

Design for structural flexibility using connected morphable components based topology optimization

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Science China(Technological Sciences) 2016年第6期59卷 839-851页

作者： deng jia Dong CHEN Wei Department of Mechanical Engineering Northwestern University

In topology optimization of structures considering flexibility, degenerated optimal solutions, such as hinges, gray areas and disconnected structures may appear. In this paper, built upon the newly developed morphable component based topology optimization approach, a novel representation using connected morphable components(CMC) and a linkage scheme are proposed to prevent degenerating designs and to ensure structure integrity. A lower bound condition of the thickness of each component is also incorporated to completely remove the smallest components in an optimal configuration. Designs of flexible structures, such as compliant mechanism design, maximum compliance structure design, and design of low-frequency resonating micro devices are studied to validate the proposed methodology. Our work demonstrates that the new methodology can successfully prevent degeneration solutions and possesses other advantages, such as minimum member size control in topology optimization of flexible structures.

关键词： topology optimization connected component degenerated designs

Spatial distribution and dynamics of carbon storage in natural Larix gmelinii forest in Daxing'anling mountains of Inner Mongolia,northeastern China

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Journal of Mountain Science 2017年第8期14卷 1633-1641页

作者： MENG Sheng-wang LIU Qi-jing jia quan-quan ZHUANG Hui-xia QI Ying LU Cheng-xue deng Liu-bao College of Forestry Beijing Forestry University Forestry Industry Bureau of Inner Mongolia

In order to clarify the geographic distribution and change of natural Larix gmelinii forest in carbon storage in Daxing'anling mountains(Great Khingan Range) in North China's Inner Mongolia, an area-irrelevant conversion equation of biomass from timber volume in the form of B = 0.6966 V was developed by using survey data. Based on the equation, the carbon storage was estimated at 190.172 Tg, and the average carbon density was 41.659 Mg/hm^2(area 4.565 × 10~6 hm^2). Carbon stored in standing trees was predominantly distributed in mid-age and mature forests and mainly stocked in the northern part of the study area. Assuming the carbon density of intact area as the maximum value, the potential carbon storage in the entire study area would be 263.674 Tg, approximately 1.4 times of the actual level. Over the period of 1995 to 2010, the carbon storage and carbon densityincreased by 3.260 Tg and 0.224 Mg/hm^2, respectively, indicating a weak carbon sink. Comparing with China's national average level, the carbon density in this area is not as high as expected. Forest quality in terms of carbon capacity is expected to be enhanced by appropriate management schemes under the in-implementation program of forest protection.

关键词： Biomass conversion equation Carbonstorage Great Khingan Range Distribution Larixgmelinii

Analysis of Stored Energy in Cold-Rolled Copper Using Bulk and Microstructure-Based Techniques

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Acta Metallurgica Sinica(English Letters) 2016年第4期29卷 313-319页

作者： Shan-quan deng Andy Godfrey Wei Liu Key Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University

Measurements of stored energy have been obtained for samples of copper cold-rolled to von Mises strains between 0.42 and 5.21 using both differential scanning calorimetry （DSC）, and based on measurements of microstructural parameters in the transmission electron microscope （TEM）. In both cases, a linear increase in stored energy with strain is found. The ratio between the two measured values varies, however, over a significant range, indicating that some caution is needed in determining the relative difference in energy associated with deformation microstructure heterogeneities in a given sample. Comparison of the stored energy with the flow stress suggests that the TEM-based measurements reflect the dislocation density content responsible for the flow stress, but that the DSC technique additionally measures other contributions to the stored energy, such as the presence of balanced internal stresses.

关键词： Stored energy Differential scanning calorimetry Microstructure Flow stress Copper