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气候变暖下大兴安岭落叶松径向生长对温度的响应

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植物生态学报 2017年第3期41卷 279-289页

作者：常永兴陈振举张先亮白学平赵学鹏李俊霞陆旭沈阳农业大学林学院树木年轮实验室沈阳110866 中国森林生态系统监测网络辽宁辽河平原森林生态系统定位研究站辽宁昌图112500

大兴安岭是我国气候变暖的敏感地区。为比较在升温过程中不同地区落叶松(Larix gmelinii)径向生长对温度的响应差异,在大兴安岭主脉南段、中段和北段进行树木年轮取样,建立了各点年轮宽度年表,根据年表第一主成分载荷系数分类最终合成... 详细信息

大兴安岭是我国气候变暖的敏感地区。为比较在升温过程中不同地区落叶松(Larix gmelinii)径向生长对温度的响应差异,在大兴安岭主脉南段、中段和北段进行树木年轮取样,建立了各点年轮宽度年表,根据年表第一主成分载荷系数分类最终合成南部、中部和北部各区年轮指数。利用相关函数分析了落叶松径向生长与温度变化的关系,结合主成分分析对比了不同地区树木年轮宽度变化对温度的响应差异。结果表明:落叶松径向生长对温度变化的响应呈现明显的南北差异(中部>北部>南部);南部年轮指数与上年11月到当年4月的平均温度显著相关,中部年轮指数与上年生长季(6–8月)和当年3–10月的平均温度显著负相关,北部年轮指数与生长季前(4–5月)的平均温度极显著正相关。气候变暖背景下,高温引起的区域暖干化使土壤水分成为限制落叶松径向生长的主要因子,土壤干旱程度加剧使落叶松生长对温度变化的响应增强。胸高断面积增量指示的落叶松生产力经历了从响应低温胁迫到响应高温引起的水分胁迫的转变。未来几十年,若温度持续升高,大兴安岭地区落叶松径向生长量将呈南部和中部降低、北部升高的趋势。

关键词：气候变暖大兴安岭落叶松年轮宽度径向生长温度变化敏感度

Supercoherent State of the Orthosymplectic (2,1) Superalgebra

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Chinese Physics Letters 2001年第7期18卷 844-846页

作者： chen yong-Qing SONG xing-Chang Department of Physics Chemistry and BiologyShenzhen Institute of EducationShenzhen 518029 Department of Physics Peking UniversityBeijing 100871

The normalization supercoherent state of the orthosymplectic(OSP)(2,1)superalgebra is constructed and its properties are discussed in *** new inhomogeneous differential realizations of the OSP(2,1)superalgebras are *** may be of use for determining new concrete structure of the quasi-exactly-solvable hamiltonian corresponding to the OSP(2,1)supersymmetric quantum system.

关键词： coherent symplectic algebra

Gut-brain axis as a bridge in obesity and depression:Mechanistic exploration and therapeutic prospects

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World Journal of Psychiatry 2025年第1期15卷 12-20页

作者： Rui-Ying Fang Xiao-Rui Pan Xin-xing Zeng Zheng-Zheng Li Bo-Fan chen Hai-Min Zeng Jie Peng The Second Clinical Medical College The Second Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina

A recent study by Wang et al,published in the World Journal of Psychiatry,provided preventative and therapeutic strategies for the comorbidity of obesity and *** gut-brain axis,which acts as a two-way communication system between the gastrointestinal tract and the central nervous system,plays a pivotal role in the pathogenesis of these *** suggests that metabolic byproducts,such as short-chain fatty acids,lipopolysaccharide and bile acids,which are generated by the gut microbiota,along with neurotransmitters and inflammatory mediators within the gut-brain axis,modulate the host's metabolic processes,neuronal regulation,and immune responses through diverse *** interaction between obesity and depression via the gut-brain axis involves disruptions in the gut microbiota balance,inflammatory immune responses,and alterations in the neuroendocrine *** the gut-brain axis,for example,through a ketogenic diet,the use of probiotics,and the supplementation of antioxidants,offers new remedial approaches for obesity and *** research that explores the mechanisms of the gut-brain axis is needed to provide more evidence for clinical treatment.

关键词： Gut-brain axis Obesity Depression Gut microbiota Mechanism

Bulk metallic glass rings prepared by a modified water quenching method

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 108-111页

作者： xing-chao Zhang yong Zhang Xiao-hua chen Guo-liang chen State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Bulk metallic glass rings have the potential applications as annular gasket and active solder in special fields. The bulk metallic glass ring of ZГ41.2Ti13.8Cu12.5Ni10.0Be22.5 with the outer diameter, the inner diameter, and the thickness of 38, 36, and 5 mm, respectively, was prepared by using a special shaped quartz tube water quenching method. The mechanical properties along the whole cross section were investigated by a nanoindentation method, and no evident variation of the Young＇s modulus and hardness was found, further indicating the single amorphous structure. Amorphous ring and tube-shape parts with different dimensions can be produced by this method.

关键词： bulk metallic glass machine parts water quenching mechanical properties

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

Crystal Engineering of Multiple-component Organic Compound： Organic co-Crystals of the Functional Groups of Carboxyl and Amino with Persistent Hydrogen Bonding Motifs

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Chemical Research in Chinese Universities 2013年第3期29卷 408-413页

作者： SONG Ge BAI Feng-ying xing Na chen chen SHAN Hui xing yong-heng College of Chemistry and Chemical Engineering College of Life Science Liaoning Normal University Dalian 116029 P. R. China

Three small organic molecular co-crystal compounds （C3N6H6）·（C6H10O4）·H2O（I）, C3HsN2O（3） and （H4btec）2.（4,4＇-bipy）（4）（H4btec=1,2,4,5-benzenetetracarboxylic acid, 4,4＇-bipy=4,4＇-bipyridine） and one coordination supramolecular compound [Mn（CEO4）（HEO）E]＇C6HllNO2（2） were synthesized by hydrothermal reaction. They were characterized by elemental analysis, infrared（IR） spectroscopy and single crystal X-ray diffraction（XRD）. Structural analyses reveal that these 2D or 3D supramolecular networks of the compounds were formed by C--H…O, N--H…O, N--H…N, O--H…O and O-H…N hydrogen bonds. Therein, the functional groups of--COOH, --NH2 and --OH play important roles in constructing supramolecular architectures.

关键词： co-Crystal compound Hydrogen bond Hydrothermal reaction

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期 12-14页

作者： Wei-Lei Zhou Siwei Wang yong chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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Are patients recovering from Kawasaki disease at increased risk for accelerated atherosclerosis? A meta-analysis

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World Journal of Pediatrics 2021年第5期17卷 476-483页

作者： Yuan-Yuan Zeng Feng chen yong Zhang xing Ji Department of Pharmacy Children's Hospital of Nanjing Medical University72 Guangzhou RoadNanjing 210008China

Background Recent studies have suggested that Kawasaki disease(KD)may cause endothelial dysfunction,which can potentially induce ***,there is still no consensus on the relationship between KD and *** article aimed to determine whether patients with a history of KD may be at increased risk for accelerated atherosclerosis via a *** The PubMed,Embase,and SpringerLink databases were systematically *** on risk factors for ath-erosclerosis were included.A meta-analysis of case-control studies was performed using RevMan 5.3 *** Twenty studies were included with a total of 1684 subjects(990 patients after KD and 694 controls).The meta-analysis showed that the level of carotid intima media thickness(cIMT)(95%CI:0.01,0.03;P=0.005)and high-sensitivity C-reactive protein(hsCRP)(95%CI:0.00,0.10;P=0.03)were significantly higher in patients after KD than controls,whereas flow-mediated dilatation(FMD)(95%CI:-5.14,-1.26;P=0.001)in patients after KD was significantly *** were no significant differences in total cholesterol(TC)(95%CI:-0.13,5.92;P=0.06),low-density lipoprotein cholesterol(LDL)(95%CI:-0.65,2.08;P=0.31),or triglycerides(TG)(95%CI:-1.94,8.03;P=0.23).Conclusion Endothelial dysfunction and infammatory processes may exist in patients with a history of KD,which are risk factors for the development of atherosclerosis.

关键词： Atherosclerosis Endothelial dysfunction Kawasaki disease Meta-analysis

Effect of low-speed waterjet pressure on the rock-breaking performance of unsubmerged cavitating abrasive waterjet

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Petroleum Science 2024年第4期21卷 2638-2649页

作者： chen-xing Fan Deng Li yong Kang Hai-Tao Zhang Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan UniversityWuhan430072HubeiChina School of Power and Mechanical Engineering Wuhan UniversityWuhan430072HubeiChina

Unsubmerged cavitating abrasive waterjet(UCAWJ)has been shown to artificially create a submerged environment that produces shear cavitation,which effectively enhances rock-breaking *** shear cavitation generation and collapse intensity depend on the pressure difference between the intermediate high-speed abrasive waterjet and the coaxial low-speed ***,the effect of the pressure of the coaxial low-speed waterjet is *** this purpose,the effect of low-speed waterjet pressure on rock-breaking performance at different standoff distances was experimentally investigated,and the effects of erosion time and ruby nozzle diameter on erosion performance were ***,the micromorphology of the sandstone was observed at different *** results show that increased erosion time and ruby nozzle diameter can significantly improve the rock-breaking *** different standoff distances,the mass loss increases first and then decreases with the increase of low-speed waterjet pressure,the maximum mass loss is 10.4 g at a low-speed waterjet pressure of0.09 *** surface morphology of cavitation erosion was measured using a 3D profiler,the increase in both erosion depth and surface roughness indicated a significant increase in the intensity of the shear cavitation *** a low-speed waterjet pressure of 0.18 MPa,the cavitation erosion surface depth can reach 600μm with a roughness of 127μm.

关键词： Rock-breaking Coaxial low-speed waterjet pressure Abrasive waterjet Cavitation Unsubmerged environment