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Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

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Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong na Li mai-He Li Yu Cong Haibo Du Decai Gao Hong s.He Key Laboratory of Geographical Processes and Ecological security in Changbai mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China school of natural Resources University of MissouriColumbiaMO65211USA swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China school of Life science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TsAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TsALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NsC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TsAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TsAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TsAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TsAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NsC) Non-treeline species sink activity stressful environments Upper elevation limit

Improvement of mechanical properties and investigation of strengthening mechanisms on the Ti_(3)AlC_(2) ceramic with nanosized WC addition

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Journal of Advanced Ceramics 2024年第6期13卷 861-876页

作者： Yi Zhong Ying Liu Qinkai Jiang na Jin Zifeng Lin Jinwen Ye school of materials science&Engineering Sichuan UniversityChengdu 610065China Yibin R&D Park Yibin Industrial Technology Research InstituteSichuan UniversityYibin 644005China

Ti_(3)AlC_(2) (TAC) has great potential for use as an ablation material in aerospace applications due to its great oxidation/ablation resistance, but its high-temperature strength and thermal shock resistance still have much room for simultaneous improvement under fast temperature variation conditions. Herein, we used Ti_(3)AlC_(2) and WC powders as raw materials and successfully fabricated textured (Ti,W)_(3)AlC_(2) ceramic with small amounts of TiC and Al_(2)O_(3), and room temperature mechanical properties such as flexural strength (1146±46.9 mPa), fracture toughness (11.78±0.44 mPa·m^(1/2)), and hardness (5.81±0.11 GPa) at 5 wt% WC addition were achieved. The high-temperature strength of the ceramic was significantly improved, and better thermal shock resistance from 298 to 1173 K was simultaneously acquired together with the regulation of the elastic modulus, thermal conductivity, and thermal expansion coefficient, providing (Ti,W)_(3)AlC_(2) with more possibilities for fast-temperature variation applications. strengthening and toughening mechanisms were proposed. scanning transmission electron microscopy high-angle annular dark-field imaging (sTEm-HADDF) showed that W randomly replaced the Ti1 and Ti2 sites of Ti_(3)AlC_(2), providing a good reference for establishing crystal models, and further density functional theory (DFT) calculations based on these models indicated a higher fracture energy of (Ti,W)_(3)AlC_(2) along different crystal planes, providing superior resistance to transgranular fracture;a lower mismatch degree of (Ti,W)_(3)AlC_(2)/Al_(2)O_(3) resulted in stronger interface bonding, resulting in greater resistance to intergranular fracture as well as more balanced stress distributions at different interfaces.

关键词： mechanical properties solid solution mAX phase transmission electron microscopy(TEm) ceramic atomic structure

Associations between CD133,CK19 and G2/m in cirrhotic HCV(genotype-4)patients with or without accompanying tumor

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BIOCELL 2018年第2期42卷 55-60页

作者： Hoda m.EL-EmsHATY Entsar A.sAAD m.na s.gouida Zahraa R.ELsHAHAWY Gastroenterology surgical Center Faculty of MedicineMansoura UniversityEgypt Chemistry Department Faculty of ScienceDamietta UniversityDamiettaEgypt mansoura Children Hospital Faculty of MedicineMansoura UniversityEgypt

Hepatitis C virus(HCV)-cirrhotic patients have the highest threat of developing hepatocellular carcinoma(HCC)and may be at risk of extra hepatic *** present study was designed to investigate CD133 and CK19 in HCV(genotype-4)-cirrhotic patients with/without HCC or extra hepatic cancer,to assess the degree of their correlation with cell cycle abnormalities and finally to assess the role of their combination as diagnostic tool for discrim.nation of cirrhotic patients with HCC from those with extra hepatic *** study included 77 HCV-cirrhotic patients and 20 healthy non-disease control *** were categorized histo-pathologically into:24 have only liver cirrhosis,26 with HCC,and 27 patients with extra hepatic *** cycle abnormalities,CD133 and CK19 were determined by flow cytometry ***133 and CK19 showed marked elevation in HCC and extra hepatic cancer compared with liver cirrhosis and control subjects(psitive associations were noted between CK19,CD133 and G2/*** were gradually increased with progression from liver cirrhosis to *** of the three showed the best AUC(0.978)and accuracy(92.5%)for discrim.nation of HCC from extra hepatic *** CD133 with G2/m and CK19 comprises an excellent diagnostic panel for discrim.nation of HCV-cirrhotic patients with HCC from those with extra hepatic cancer.

关键词： Cell cycle Diagnostic performance Liver Panel

Neutrophil peptide 1 accelerates the clearance of degenerative axons during Wallerian degeneration by activating macrophages after peripheral nerve crush injury

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Neural Regeneration Research 2024年第8期19卷 1822-1827页

作者： Yuhui Kou Yusong Yuan Qicheng Li Wenyong Xie Hailin Xu na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina national Center for Trauma medicine BeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina Department of Central Laboratory and Institute of Clinical molecular Biology Peking University People’s HospitalBeijingChina

macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still *** prelim.nary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve ***,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains *** study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush *** functions of RAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent *** debris phagocytosis was observed using the CUBIC(Clear,Unobstructed Brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian *** inflammatory factor expression in different polarization states was detected using a protein *** results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating m2 *** axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 *** peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in ***,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.

关键词： axonal debris inflammatory factors macrophages neutrophil peptide 1 peripheral nerve injury peripheral nerve regeneration RAW 264.7 cells sciatic nerve Wallerian degeneration

The infection kinetics and transmission potential of two Guaico Culex viruses in Culex quinquefasciatus mosquitoes

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Virologica sinica 2024年第2期39卷 228-234页

作者： Ru-Yi Chen Teng Zhao Jing-Jing Guo Feng Zhu na-na Zhang Xiao-Feng Li Hai-Tao Liu Fei Wang Yong-Qiang Deng Cheng-Feng Qin College of Bioscience and Bioengineering Jiangxi Agricultural UniversityNanchang330045China state Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMSBeijing100071China school of Life sciences Southwest Forestry UniversityKunming650224China

Guaico Culex virus(GCXV)is a newly identified segmented Jingmenvirus from Culex *** in Central and south *** genome of GCXV is composed of four or five single-stranded positive Rna ***,the infection kinetics and transmission capability of GCXV in mosquitoes remain *** this study,we used reverse genetics to rescue two GCXVs(4s and 5s)that contained four and five Rna segments,respectively,in C6/36 *** in vitro characterization revealed that the two GCXVs exhibited comparable replication kinetics,protein expression and viral ***,GCXV Rnas were detected in the bodies,salivary glands,midguts and ovaries of Culex quinquefasciatus at 4–10 days after oral *** addition,two GCXVs can colonize *** eggs,resulting in positive rates of 15%–35%for the second gonotrophic *** conclusion,our results demonstrated that GCXVs with four or five Rna segments can be detected in *** eggs during the first and second gonotrophic cycles after oral infection.

关键词： Guaico Culex virus(GCXV) Jingmenvirus Culex quinquefasciatus Vertical transmission

mechanical reliable,NIR light-induced rapid self-healing hydrogel electrolyte towards flexible zinc-ion hybrid supercapacitors with low-temperature adaptability and long service life

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Journal of Energy Chemistry 2024年第5期92卷 63-73页

作者： Tengjia Gao na Li Yang Yang Jing Li Peng Ji Yunlong Zhou Jianxiong Xu school of materials and Advanced manufacturing Hunan Key Laboratory of Electrochemical Green Metallurgy TechnologyHunan University of TechnologyZhuzhou 412007HunanChina school of Life sciences and Chemistry Hunan Key Laboratory of Biomedical Nanomaterials and DevicesHunan University of TechnologyZhuzhou 412007HunanChina

Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and ***,freezing of electrolytes at low temperature(subzero)leads to drastic reduction in ionic conductivity and mechanical properties that deteriorates the performance of flexible ***,the mechanical fracture during arbitrary deformations significantly prunes out the lifespan of the flexible ***,a Zn^(2+)and Li^(+)co-doped,polypyrrole-dopamine decorated sb_(2)s_(3)incorporated,and polyvinyl alcohol/poly(N-(2-hydroxyethyl)acrylamide)double-network hydrogel electrolyte is constructed with favorable mechanical reliability,anti-freezing,and self-healing *** addition,it delivers ultra-high ionic conductivity of 8.6 and 3.7 s m^(-1)at 20 and−30°C,respectively,and displays excellent mechanical properties to withstand tensile stress of 1.85 mPa with tensile elongation of 760%,together with fracture energy of 5.14 mJ m^(-3).Notably,the fractured hydrogel electrolyte can recover itself after only 90 s of infrared illum.nation,while regaining 83%of its tensile strain and almost 100%of its ionic conductivity during−30–60°***,ZICs coupled with this hydrogel electrolyte not only show a wide voltage window(up to 2 V),but also provide high energy density of 230 Wh kg^(-1)at power density of 500 W kg^(-1)with a capacity retention of 86.7%after 20,000 cycles under 20°***,the ZICs are able to retain excellent capacity even under various mechanical deformation at−30°*** contribution will open up new insights into design of advanced wearable flexible electronics with environmental adaptability and long-life span.

关键词： Flexible zinc ion supercapacitor Hydrogel electrolyte self-healing Anti-freezing

structural effects induced by dialysis-based purification of carbon nanomaterials

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nano materials science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do Rego A.s.Viana A.J.s.Fernandes A.J.Fielding R.A.Videira m.C.Oliveira CQ-VR and Chemistry Department University of Trás-os-Montes e Alto Douro BsIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUImTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： nanocarbon surface functionalization NmR XPs Hydrophilic carbon Paramagnetic

single-cell Rna sequencing analysis of the retina under acute high intraocular pressure

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Neural Regeneration Research 2024年第11期19卷 2522-2531页

作者： shaojun Wang siti Tong Xin Jin na Li Pingxiu Dang Yang sui Ying Liu Dajiang Wang Division of Ophthalmology The Third Medical Center of PLA General HospitalBeijingChina Department of Ophthalmology Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

High intraocular pressure causes retinal ganglion cell injury in primary and secondary glaucoma diseases,yet the molecular landscape characteristics of retinal cells under high intraocular pressure remain *** models of acute hypertension ocular pressure were established by injection of cross-linked hyaluronic acid hydrogel(Healaflow■).single-cell Rna sequencing was then used to describe the cellular composition and molecular profile of the retina following high intraocular *** results identified a total of 12 cell types,namely retinal pigment epithelial cells,rod-photoreceptor cells,bipolar cells,müller cells,microglia,cone-photoreceptor cells,retinal ganglion cells,endothelial cells,retinal progenitor cells,oligodendrocytes,pericytes,and *** single-cell Rna sequencing analysis of the retina under acute high intraocular pressure revealed obvious changes in the proportions of various retinal cells,with ganglion cells decreased by 23%.Hematoxylin and eosin staining and TUNEL staining confirmed the damage to retinal ganglion cells under high intraocular *** extracted data from retinal ganglion cells and analyzed the retinal ganglion cell cluster with the most distinct *** found upregulation of the B3gat2 gene,which is associated with neuronal migration and adhesion,and downregulation of the Tsc22d gene,which participates in inhibition of *** study is the first to reveal molecular changes and intercellular interactions in the retina under high intraocular *** data contribute to understanding of the molecular mechanism of retinal injury induced by high intraocular pressure and will benefit the development of novel therapies.

关键词： apoptosis axon degeneration high intraocular pressure microglia ocular hypertension photoreceptor cells retina retinal degeneration retinal ganglion cells single-cell Rna sequencing

Flexible mille-feuille structure electromagnetic interference shielding film with excellent thermal conductivity and Joule heating

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nano Research 2024年第5期17卷 4544-4554页

作者： Dingwen Yin Huijuan Xiu simin Wang Yanfei Pan na Li Rui Cheng shaoyan Huang sha Fan Jinbao Li College of Bioresources Chemical&materials Engineering Shaanxi University of Science&TechnologyXi'an 710021China national Demonstration Center for Experimental Light Chemistry Engineering Education Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper DevelopmentXi'an 710021China College of material science and Art Design Inner Mongolia Agricultural UniversityHohhot 010018China

The intelligent electronic devices have urgent demands for electromagnetic interference(EmI)shielding films with excellent heat dissipation ***,it is challenging to obtain excellent EmI shielding and thermal conductivity performances ***,inspired by mille-feuille structure,the multifunctional EmI shielding films developed by a layer-by-layer self-assembly and hot-pressing *** ingenious introduction of silver nanoparticles(AgNPs)with large specific surface area and highly conductive into the network formed by TEmPO-oxidized cellulose nanofibrils(TOCNFs)with large aspect ratio to form the TOCNFs/*** the graphene nanoplates(GNPs)with high conductivity loss distributed alternately with TOCNFs/AgNPs to construct mille-feuille structure,which had highly efficient conductive network,complete thermally conduction pathway and rich heterogeneous ***,the designed films presented high electrical conductivity of 8520 s/cm,superb EmI effectiveness(sE)of 98.05 dB,and excellent thermal conductivity of 18.82 W/(m·K).Furthermore,the films possessed outstanding Joule heating performances with low voltages,including high heating temperature(100℃),fast response time(s),and impressive heating stability and ***,such high-performance EmI shielding films with fascinating thermal conductivity and Joule heating performances have substantial application in flexible electronics,electromagnetic waves shielding and thermal m.nagement.

关键词： TEmPO-oxidized cellulose nanofibrils/silver nanoparticles(TOCNFs/AgNPs) mille-feuille structure electromagnetic interference shielding thermal conductivity Joule heating