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Changes of Soil Water, Organic Matter, and Exchangeable Cations Along a Forest Successional Gradient in Southern China

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Pedosphere 2007年第3期17卷 397-405页

作者： YAN Jun-Hua ZHOU guo-yi zhang De-Qiang CHU guo-Wei South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 （China）

Information on the distribution patterns of soil water content （SWC）, soil organic matter （SOM）, and soil exchangeable cations （SEC） is important for managing forest ecosystems in a sustainable manner. This study investigated how SWC, SOM, and SEC were influenced in forests along a successional gradient, including a regional climax （monsoon evergreen broad-leaved forest, or MEBF）, a transitional forest （coniferous and broad-leaved mixed forest, or MF）, and a pioneer forest （coniferous Masson pine （Pinus rnassoniana） forest, or MPF） of the Dinghushan Biosphere Reserve in the subtropical region of southern China. SWC, SOM, and SEC excluding Ca^2＋ were found to increase in the soil during forest succession, being highest in the top soil layer （0 to 15 cm depth） except for Na^＋. The differences between soil layers were largest in MF. This finding also suggested that the nutrients were enriched in the topsoil when they became increasingly scarce in the soil. There were no significant differences （P = 0.05） among SWC, SOM, and SEC. A linear, positive correlation was found between SWC and SOM. The correlation between SOM and cation exchange capacity （CEC） was statistically significant, which agreed with the theory that the most important factor determining SEC is SOM. The ratio of K^＋ to Na^＋ in the topsoil was about a half of that in the plants of each forest. MF had the lowest exchangeable Ca^2＋ concentration among the three forests and Ca^2＋：K^＋ in MPF was two times higher than that in MF. Understanding the changes of SWC, SOM, and CEC during forest succession would be of great help in protecting all three forests in southern China.

关键词： forest succession soil exchangeable cations soil organic matter soil water content

Template Effect on Structure and Morphology of Ni(OH)_2 Powders Prepared by Hydro chemical Method

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Journal of Central South University 2000年第1期12卷 20-24页

作者： LIU Zhi hong,LI Qi hou,XU Xiao lin,guo Xue yi,zhang Duo mo (Department of Metallurgical Science and Engineering, Central South University of Technology, Changsha 410083, China) 1. Department of Metallurgical Science and Engineering Central South University of Technology 410083 Changsha China

The template effect controlling the structure and morphology of ultrafine particles was described. Ni(OH) 2 powders were prepared by NH 3 coordination precipitation method. The effects of SO 2- 4, NO - 3, Cl -, NH 3, pH value on Ni(OH) 2 structure and morphology were investigated experimentally, explained with the theoretical model that the growth units were the polyhedral structure of coordination anions. The results showed that the structure and morphology of Ni(OH) 2 were effectively controlled by the growth units, the dimensions and the linking patterns of the growth units vary with the changes of physical and chemical conditions in the aqueous solution.

关键词： Ni(OH)_2 structural control polyhedral structure of coordination anions growth units

Synthesis, characterization and catalytic application of H4SiW12O40/MCM-48 in the esterification of methacrylic acid with n-butyl alcohol

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Journal of Chemistry and Chemical Engineering 2009年第1期3卷 61-65页

作者： YANG Shui-jin yiN guo-jun zhang yi-jun WANG Dong-ming Hubei Key Laboratory of Pollutant Analysis ＆ Reuse Technology College of Chemistry and Environmental Engineering Hubei Normal University Huangshi 435002 China

A novel environmental friendly catalyst, H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H4SiW12O40/MCM-48 was studied with methacrylic acid and n-butyl alcohol as reactants. H4SiW12O40/MCM-48 was an excellent catalyst for the synthesis of n-butyl methacrylate and Keggin structure ofH4SiW12O40 kept unchanged after impregnated on surface of the molecular sieve support. Effects of n（methacrylic acid）： n（n-butyl alcohol）, catalyst dosage, cyclohexane （water-stripped reagent） and reaction time on the yields of the product were investigated. The optimum conditions have been found, that is, molar ratio of acid to alcohol is 1：1.5, mass ratio of catalyst used to the reactant is 1.5%, cyclohexane is 10 mL and reaction time is 1.5h. Under these conditions, the yield of n-butyl methacrylate can reach 73.2%.

关键词： MCM-48 molecular sieve silicotungstic acid n-butyl methacrylate catalysis

Akt-centered amplification loop plays a critical role in vascular endothelial growth factor/stromal cell-derived factor 1-αcross-talk and cardioprotection

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Chinese Medical Journal 2011年第22期124卷 3800-3805页

作者： guo Wen-yi zhang Dian-xin LI Wei-jie ZHAO Zhi-jing LIU Bing WANG Hai-chang LI Fei Department of Cardiology Xijing Hospital Fourth Military Medical University Xi＇an Shaanxi 710032 China

Background Vascular endothelial growth factor （VEGF） is one of major mediators of angiogenesis and survival factor in some tissue, however, its direct effects on cardiomyocytes remain poorly understood. Methods Rat neonatal ventricular myocytes were cultured in vitro. Akt phosphorylation was measured by Western blotting; the expression of stromal cell-derived factor α（SDF-1α）/CXCR4 axis was evaluated by real-time PCR and Western blotting. LY294002 and AMD3100 were used to interfere with the signaling of VEGF and SDF-1α/CXCR4 axis. Cardiac myocytes viability and injury were evaluated by trypan blue staining and lactate dehydrogenase （LDH） release. Results Treatment of neonatal rat ventricular myocytes with VEGF induced phosphorylation of Akt in a dose and FIk-1 dependent manner. VEGF attenuated H202 induced cardiac myocyte death. The phosphoinositol-3-kinase （PI3K） inhibitor, LY294002 and FIk-1 antibody abolished the beneficial effects of VEGF on H202 induced cell death. In the mean time SDF-1α-CXCR4 axis was up-regulated by VEGF through PI3K-Akt signaling and contributed to the protective effects of VEGF on H202 induced cell death. Interestingly, SDF-1α also promoted production of VEGF in cultured cardiac myocytes and LY294002 reversed the up-reguLation of VEGF induced by SDF-1α. Conclusion VEGF has direct protective effects on cardiomyocytes; a crosstalk between VEGF and SDF-1α through PI3K-Akt serves a survival role in cardiomvocvtes in vitro.

关键词： vascular endothelial growth factor cardiomyocyte, stromal cell-derived factor a survival PI3K-Akt

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International Journal of Dermatology and Venereology 2022年第2期5卷 113-115页

作者： Xiao-Li Zheng Fei yi yi-Qun Jiang Qian-Qiu Wang Guan-Zhao Liang Yue-Ping yin guo-yi zhang Department of STD Clinical Management and Intervention National Center for Sexually Transmitted Disease ControlHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China Department of Dermatology Institute of DermatologyPeking University Shenzhen HospitalShenzhen Peking University-The Hong Kong University of Science and Technology Medical CenterShenzhen 518036China Department of Pathology Chinese Center for Disease Control and PreventionHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China Department of Mycology Chinese Center for Disease Control and PreventionHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China STD Reference Laboratory Chinese Center for Disease Control and PreventionHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China Outpatient Department Hospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China.

Introduction:Verrucous carcinoma is a rare variant of squamous cell *** generally grows exogenously and bone erosion is *** we present a case of verrucous carcinoma on the foot with toe *** presentation:A 64-year-old man presented with a 6-year history of a slowly growing exogenous hyperkeratotic verrucous lesion on the right fifth toe,which had been absent for *** the lesion appeared,he had undergone nail extraction on this *** culture of fungi and mycobacteria were ***-dimensional computed tomography showed that the fifth toe of the right foot was *** examination showed that the lesion was exogenous and verrucous and exhibited moderate keratinocyte *** with clinical manifestation and histopathological examination,verrucous carcinoma is *** lesion was surgically excised,and the patient was followed up for more than 6months without ***:Verrucous carcinoma is an exophytic tumor with verrucous growth at the beginning,which can invade deep tissues and even cause limb *** encountering a patient with a wart-like plaque on the foot that responds poorly to conventional treatments,clinicians should maintain a high degree of clinical vigilance and a low threshold for ***:We observed a rare outcome of toe absence associated with verrucous ***,early diagnosis of verrucous carcinoma is very *** excision is an effective treatment at *** resection is usually required to avoid recurrence.

关键词： verrucous carcinoma squamous cell carcinoma surgical excision case report

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan Shi Qun yi Yao Liu yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Complete reconstruction Co-based complex Precatalysts Oxygen evolution reaction

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life Sciences 2025年第1期 272-283页

作者： Yuwei Hua yizhi zhang Zhenming guo Shan Bian Yong zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

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Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第01期 26-34页

作者： Yutao zhang Juan Li Wei-Hong Zhu Zhiqian guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

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Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan zhang yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction