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Comparison of antimony and arsenic behaviour at the river-lake junction in the middle of the Yangtze River Basin

Journal of Environmental Sciences 2024年第2期136卷 189-200页

作者： Huiji Liu wei zeng Ziyang Lai Mengchang He Chunye Lin wei Ouyang Xitao Liu State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Advanced Interdisciplinary Institute of Environment and Ecology Beijing Normal UniversityZhuhai 519087China

As typical metalloid toxic elements widely distributed in environmental media,the geochemical behaviour of antimony(Sb)and arsenic(As)affects environmental safety.We selected the surface waters and sediments at the river-lake junction of Dongting Lake as the research objects,analysed the concentration and chemical partitioning of Sb and As,assessed its contamination and ecological risk levels,and discussed its sources and potential influencing factors.The concentrations of dissolved Sb and As in surface waters were low(<5.46μg/L),and the concentrations of Sb and As in surface sediments were 2.49-22.65mg/kg and 11.10-136.34 mg/kg,respectively.Antimony and As in sediments were mainly enriched in the fraction of residues,but the proportion of As in bioavailability was significantly higher than that of Sb.Although the contamination level of Sb was higher than that of As,the risk assessment code(RAC)showed that the ecological risk level of As was higher than that of Sb.Rainwater erosion and mining activities(in the midstream of Zijiang River)were the main contaminated sources of Sb,while As was affect mainly by rainwater erosion.The contamination and ecological risk of Sb in the inlet of the Zijiang River should receive considerable attention,while those of As in the inlet of the Xiangjiang River should also be seriously considered.This study highlights the need for multi-index-based assessments of contamination and ecological risk and the importance of further studies on the environmental behaviour of metalloids in specific hydrological conditions,such as river-lake junctions.

关键词： Contamination Ecological risks Antimony(Sb) Arsenic(As) River-lake junction Dongting Lake

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Understory seedlings of Quercus mongolica survive by phenological escape

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Forest Ecosystems 2024年第2期11卷 236-246页

作者： Shixiong Wu Ying Liu Lulu He wei zeng Qijing Liu College of Forestry Beijing Forestry UniversityBeijing100083China

Understanding understory seedling regeneration mechanisms is important for the sustainable development of temperate primary forests in the context of increasingly intense climate warming events.The poor regeneration of dominant tree species,however,is one of the biggest challenges it faces at the moment.Especially,the regeneration of the shade-intolerant Quercus mongolica seedling is difficult in primary forests,which contrasts with the extreme abundance of understory seedlings in secondary forests.The mechanism behind the interesting phenomenon is still unknown.This study used in-situ monitoring and nursery-controlled experiment to investigate the survival rate,growth performance,as well as nonstructural carbohydrate (NSC) concentrations and pools of various organ tissues of seedlings for two consecutive years,further analyze the understory light availability and simulate the foliage carbon (C) gain in the secondary and primary forest.Results suggested that seedlings in the secondary forest had greater biomass allocation aboveground,height and specific leaf area (SLA) in summer,which allowed the seedling to survive longer in the canopy closure period.High light availability and positive C gain in early spring and late autumn are key factors affecting the growth and survival of understory seedlings in the secondary forest,whereas seedlings in the primary forest had annual negative carbon gain.Through the growing season,the total NSC concentrations of seedlings gradually decreased,whereas those of seedlings in the secondary forest increased significantly in autumn,and were mainly stored in roots for winter consumption and the following year's summer shade period,which was verified by the nursery-controlled experiment that simulated autumn enhanced light availability improved seedling survival rate and NSC pools.In conclusion,our results revealed the survival trade-off strategies of Quercus mongolica seedlings and highlighted the necessity of high light availability during the spring and autumn phenological periods

关键词： Carbon gain Nonstructural carbohydrate Recruitment Trade-off Biomass allocation

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Rh(Ⅱ)-catalyzed intermolecular carboamination of pyridines via double Csp^(2)-H bond activations

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Science China Chemistry 2024年第1期67卷 374-382页

作者： Zhongfeng Luo Jingxing Jiang Lifang Zou Xiaoyu Zhou Junshan Liu Zhuofeng Ke Fengjuan Chen Huanfeng Jiang wei zeng Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510641China School of Materials Science and Engineering PCFM LabSun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics School of Traditional Chinese MedicineSouthern Medical UniversityGuangzhou 510515China

We disclose the development of the Rh-catalyzed amine-directed remote 5,6-carboamination protocol of pyridines via dual Csp^(2)-H functionalizations.A variety of readily available 2-aminopyridines and 1,2,3-triazoles are allowed for coupling cyclization to access polyfunctionalized azaindoles.Mechanistic studies including DFT calculations unveil that relay carbenoidelectrophilic addition to pyridines and the sequential pyridyl Csp^(2)-H amination are involved in this transformation.The postsynthetic utility of this methodology is showcased by versatile and site-selective modification of azaindoles.

关键词： Rh-catalysis azaindoles pyridyl Csp^(2)-H bond carboamination coupling-cyclization

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Enhanced SERS aptasensor for sensitive detection of saxitoxin based on HAuCl/HOreaction system and Pt/Au nanozyme

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Food Science and Human Wellness 2024年

作者： Yueqing Li Xuemei Tang wei zeng Ting Wu Long Wu School of Food Science and Engineering Key Laboratory of Tropical Fruits and Vegetables Quality and Safety for State Market Regulation Hainan University

Saxitoxin （STX） is a marine biotoxin produced by cyanobacteria and methanobacteria， which is harmful to humans and aquatic organisms. Therefore， it is urgent to establish an efficient， sensitive and selective method for the screening of STX. In this paper， based on the HAuCl4/H2O2reaction system， gold nanoparticles （Au NPs） decorated Fe3O4magnetic beads (Fe3O4@Au NPs) and Pt/Au nanozymes （Pt/Au NZs）， an enhanced SERS aptasensor was proposed for sensitive and selective detection of STX. Firstly， SERS tag （4-MBA） and aptamer modified Fe3O4@Au NPs were hybridized with complementary DNA modified Pt/Au NZs （Pt/Au-cDNA） to form the specific complexes. Wherein， aptamer acted as capture agent to specifically recognize STX， Pt/Au NZs catalyzed HAuCl4/H2O2reaction to enhance SERS signal， and Fe3O4facilitated the magnetic separation and simple detection operations. The SERS aptasensor achieved sensitive detection of STX with a wide linear range from 0.02 μmol/L to 0.8 μmol/L and a low detection limit of 13 nmol/L （LOD， S/N=3）. To evaluate the performance of this method， STX were detected in the spiked seafood samples with recoveries from 78.75% to 150% with relative errors below 6.52%. Besides， the SERS aptasensor behaved good stability and repeatability， revealing its promising potential in STX detection and food safety detection.

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A simplified noncryogenic strategy to transport mesenchymal stem cells: Potential applications in cell therapy and regenerative medicine

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Genes & Diseases 2024年第3期11卷 26-29页

作者： Xiangyu Dong Yannian Gou Meichun Guo Jiamin Zhong Aohua Li Ailing Hao wei zeng Rex C.Haydon Hue H.Luu Russell R.Reid Tongchuan He Yan Xu Jiaming Fan Ministry of Education Key Laboratory of Diagnostic Medicine And Department of Clinical BiochemistryCollege of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Molecular Oncology Laboratory Department of Orthopaedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA Department of Interventional Neurology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguanGuangdong 523475China Laboratory of Craniofacial Suture Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA Institute of Sports Medicine Beijing Key Laboratory of Sports InjuriesPeking University Third HospitalBejing 100191China

With the rapid advances in stem cell research and po-tential cell-based therapies,there is an urgent need to develop safe and reliable cell transport strategies.Except for autologous stem cell-based therapies,allogeneic stem cell therapies and ex vivo genetically engineered cell therapies would require safe,efficient,and reliable cell preservation and transport methods.

关键词： transport methods simplified

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The evolving roles of Wnt signaling in stem cell proliferation and differentiation, the development of human diseases, and therapeutic opportunities

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Genes & Diseases 2024年第3期11卷 155-187页

作者： Michael Yu Kevin Qin Jiaming Fan Guozhi Zhao Piao Zhao wei zeng Connie Chen Annie Wang Yonghui Wang jiamin Zhong Yi Zhu William Wagstaff Rex C.Haydon Hue H.Luu Sherwin Ho Michael J.Lee Jason Strelzow Russell R.Reid Tong-Chuan He School of Medicine Rosalind Franklin University of Medicine and ScienceNorth ChicagoIL 60064USA Molecular Oncology Laboratory Department of Orthopedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA Ministry of Education Key Laboratory of Diagnostic Medicine and Department of Clinical BiochemistryThe School of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Department of Orthopedic Surgery The First Affliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Urology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Clinical Laboratory Medicine Shanghai Jiaotong University School of MedicineShanghai 200000China Department of Orthopaedic Surgery Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Laboratory of Craniofacial Suture Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA Department of Neurology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguanGuangdong 523475China

The evolutionarily conserved Wnt signaling pathway plays a central role in develop-ment and adult tissue homeostasis across species.Wnt proteins are secreted,lipid-modified signaling molecules that activate the canonical(β-catenin dependent)and non-canonical(β-catenin independent)Wnt signaling pathways.Cellular behaviors such as proliferation,differ-entiation,maturation,and proper body-axis specification are carried out by the canonical pathway,which is the best characterized of the known Wnt signaling paths.Wnt signaling has emerged as an important factor in stem cell biology and is known to affect the self-renewal of stem cells in various tissues.This includes but is not limited to embryonic,hematopoietic,mesenchymal,gut,neural,and epidermal stem cells.Wnt signaling has also been implicated in tumor cells that exhibit stem cell-like properties.Wnt signaling is crucial for bone formation and presents a potential target for the development of therapeutics for bone disorders.Not surprisingly,aberrant Wnt signaling is also associated with a wide variety of diseases,including cancer.Mutations of Wnt pathway members in cancer can lead to unchecked cell proliferation,epithelial-mesenchymal transition,and metastasis.Altogether,advances in the understand-ing of dysregulated Wnt signaling in disease have paved the way for the development of novel therapeutics that target components of the Wnt pathway.Beginning with a brief overview of the mechanisms of canonical and non-canonical Wnt,this review aims to summarize the cur-rent knowledge of Wnt signaling in stem cells,aberrations to the Wnt pathway associated with diseases,and novel therapeutics targeting the Wnt pathway in preclinical and clinical studies.

关键词： β-Catenin Cancer Canonical Wnt Disease Non-canonical Wnt Stem cells Targeted therapy Wnt signaling

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Canonical and noncanonical Wnt signaling: Multilayered mediators, signaling mechanisms and major signaling crosstalk

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Genes & Diseases 2024年第1期11卷 103-134页

作者： Kevin Qin Michael Yu Jiaming Fan Hongwei Wang Piao Zhao Guozhi Zhaoo wei zeng Connie Chen Yonghui Wang Annie Wang Zander Schwartz Jeffrey Hong Lily Song William Wagstaff Rex C.Haydon Hue H.Luu Sherwin H.Ho Jason Strelzow Russell R.Reid Tong-Chuan He Lewis L.Shi Chicago Medical School Rosalind Franklin University of Medicine and ScienceNorth ChicagoIL 60064USA Molecular Oncology Laboratory Department of Orthopaedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA Ministry of Education Key Laboratory of Diagnostic Medicine and Department of Clinical BiochemistryThe School of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Departments of Orthopaedic Surgery and Urology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Interventional Neurology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguanGuangdong 523475China Department of Clinical Laboratory Medicine Shanghai Jiaotong University School of MedicineShanghai 200000China School of Biomedical Engineering Vanderbilt UniversityNashvilleTN 37235USA Laboratory of Craniofacial Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA

Wnt signaling plays a major role in regulating cell proliferation and differentiation.The Wnt ligands are a family of 19 secreted glycoproteins that mediate their signaling effects via binding to Frizzled receptors and LRP5/6 coreceptors and transducing the signal either throughβ-catenin in the canonical pathway or through a series of other proteins in the nonca-nonical pathway.Many of the individual components of both canonical and noncanonical Wnt signaling have additional functions throughout the body,establishing the complex interplay between Wnt signaling and other signaling pathways.This crosstalk between Wnt signaling and other pathways gives Wnt signaling a vital role in many cellular and organ processes.Dys-regulation of this system has been implicated in many diseases affecting a wide array of organ systems,including cancer and embryological defects,and can even cause embryonic lethality.The complexity of this system and its interacting proteins have made Wnt signaling a target for many therapeutic treatments.However,both stimulatory and inhibitory treatments come with potential risks that need to be addressed.This review synthesized much of the current knowl-edge on the Wnt signaling pathway,beginning with the history of Wnt signaling.It thoroughly described the different variants of Wnt signaling,including canonical,noncanonical Wnt/PCP,and the noncanonical Wnt/Ca2+pathway.Further description involved each of its components and their involvement in other cellular processes.Finally,this review explained the various other pathways and processes that crosstalk with Wnt signaling.

关键词： β-catenin Canonical Wnt Noncanonical Wnt Signal transduction Signaling crosstalk

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Exploring the Effect of Plasticity on the Phase Imaging of TM-AFM Through Molecular Dynamics Simulations

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Acta Mechanica Solida Sinica 2024年第2期37卷 297-304页

作者： Guolin Liu Yu zeng Yaxin Chen Zheng wei School of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing100029China

In the tapping-mode atomic force microscope(TM-AFM),the probe tip continuously taps the sample surface,which may cause plastic deformation of the sample and result in energy dissipation.The energy dissipation of the probe is closely related to the scanned phase image.To quantify the energy dissipation due to plastic indentations of the sample,this study utilized a combination of molecular dynamics(MD)simulations and experiments on single-crystal copper samples,including multiple nano-indentation tests.The energy dissipation of the probe due to the plastic deformation of the sample was calculated by integrating the hysteresis curve of the indentation depth versus the force applied to the indenter.The simulation results are in good agreement with the experimental ones.Both sets of results have demonstrated that the plastic energy dissipation decreases as the number of indentations increases,and eventually the energy of the probe tends to stabilize.This equilibrium energy dissipation is associated with other dissipation mechanisms.Furthermore,it was observed that,after hundreds of taps,the dissipated energy of plastic deformation could be ignored,implying that the scanned image may not reflect the plasticity information of the sample after multiple taps of the probe on the sample surface for scanning.

关键词： Atomic force microscopy Force-distance curves Nano-indentations Plasticity Molecular dynamics

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A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

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Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： Zhi-wei Shen Shu-Feng Hu Chen zeng wei-Qing Kong Mei-Fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree

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A Study on the Performances of Solar Air Collectors Having a Hemispherical Dimple on the Absorber Plate

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Fluid Dynamics & Materials Processing 2024年第5期20卷 939-955页

作者： Shuilian Li Fan zeng Xinli wei School of Architecture and Environmental Engineering Zhengzhou Technical CollegeZhengzhou450121China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou450001China

In order to increase the efficiency of solar air collectors,a new variant with a protrusion is proposed in this study,and its performances are analyzed from two points of view,namely,in terms of optics and thermodynamics aspects.By comparing and analyzing the light paths of the protrusion and the dimple,it can be concluded that when sunlight shines on the dimple,it is reflected and absorbed multiple times,whereas for the sunlight shining on the protrusion,there is no secondary reflection or absorption of light.When the lighting area and the properties of the surfaces are the same,the absorption rate of the dimple is 10.3 percentage points higher than that of the protrusion.In the range of Reynolds number from 3000 to 11000,numerical simulations about the effects of the relative height(e/Dh=0.033–0.1)and relative spacing(p/e=4.5–8.5)of protrusions on air heat transfer and flow resistance show that,in terms of comprehensive evaluation coefficient(PF),the best relative height is 0.085,when the relative spacing is 5.A correlation of Nu and f with Re,e/Dh and p/e is obtained by linear regression of the results,in order to provide a useful reference for the design and optimization of this kind of solar air collector.

关键词： Heat transfer hemispherical protrusion dimple solar air collector correlation

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