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Linkage of microbial living communities and residues to soil organic carbon accumulation along a forest restoration gradient in southern China 被引量:1
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作者 Shuo Zhang Qi Deng +8 位作者 Ying-Ping Wang Ji Chen Mengxiao Yu Xi Fang Hongbo He Jinlei Chen pingping xu Shenhua Wang Junhua Yan 《Forest Ecosystems》 SCIE CSCD 2021年第4期765-777,共13页
Background:Forest restoration has been considered an effective method to increase soil organic carbon(SOC),whereas it remains unclear whether long-term forest restoration will continuously increase SOC.Such large unce... Background:Forest restoration has been considered an effective method to increase soil organic carbon(SOC),whereas it remains unclear whether long-term forest restoration will continuously increase SOC.Such large uncertainties may be mainly due to the limited knowledge on how soil microorganisms will contribute to SOC accumulation over time.Methods:We simultaneously documented SOC,total phospholipid fatty acids(PLFAs),and amino sugars(AS)content across a forest restoration gradient with average stand ages of 14,49,70,and>90 years in southern China.Results:The SOC and AS continuously increased with stand age.The ratio of fungal PLFAs to bacterial PLFAs showed no change with stand age,while the ratio of fungal AS to bacterial AS significantly increased.The total microbial residue-carbon(AS-C)accounted for 0.95-1.66% in SOC across all forest restoration stages,with significantly higher in fungal residue-C(0.68-1.19%)than bacterial residue-C(0.05-0.11%).Furthermore,the contribution of total AS-C to SOC was positively correlated with clay content at 0-10 cm soil layer but negatively related to clay content at 10-20 cm soil layer.Conclusions:These findings highlight the significant contribution of AS-C to SOC accumulation along forest restoration stages,with divergent contributions from fungal residues and bacterial residues.Soil clay content with stand age significantly affects the divergent contributions of AS-C to SOC at two different soil layers. 展开更多
关键词 Soil carbon stock Microbial biomass Microbial residues Forest restoration Soil clay content Soil layer
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Sparse array of sub-surface aided blockage-free multi-user mmWave communication systems
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作者 Weicong Chen Xi Yang +1 位作者 Shi Jin pingping xu 《Digital Communications and Networks》 SCIE 2020年第3期292-303,共12页
Recently,Reconfigurable Intelligent Surfaces(RISs)have drawn intensive attention in the realization of the smart radio environment.However,existing works mainly consider the RIS as a whole uniform plane,which may be u... Recently,Reconfigurable Intelligent Surfaces(RISs)have drawn intensive attention in the realization of the smart radio environment.However,existing works mainly consider the RIS as a whole uniform plane,which may be unrealistic to be installed on the facade of buildings when the RIS is extremely large.In contrast,this paper investigates a practical Sparse Array of Sub-surface(SAoS)deployment of the RIS for uplink multi-user millimeter Wave(mmWave)communication systems,in which the Mobile Stations(MSs)are distributed in the blind coverage area due to the blockage.In order to exploit the benefits of the sparse deployment,the correlation of the effective channel is firstly investigated.Then the approximation and lower bounds of the ergodic spectral efficiency are derived under frequency and spatial multiplexing scenarios,respectively.Based on the autocorrelation of the effective channel,we obtain an optimal reflect coefficient design as well as the deployment guidelines of RIS tiles.Moreover,the RIS tile scheduling algorithms are also proposed.Numerical results show that the ergodic spectral efficiency approximation matches well with the Monte Carlo result under frequency multiplexing scenarios,and the lower bound is tight under spatial multiplexing scenarios only when the effective channel is strongly correlated.On the basis of the RIS tile scheduling algorithm and the reflect coefficient design,the system performance can be significantly improved under frequency multiplexing scenarios.On the other hand,by deploying more sparse RIS tiles,we can increase the multiplexing gain under spatial multiplexing scenarios. 展开更多
关键词 Sparse array Reconfigurable intelligent surface MULTI-USER Blockage-free mmWave
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Exploration of sea anemone-inspired high-performance biomaterials with enhanced antioxidant activity 被引量:1
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作者 Lulu Wang Xiaokang Zhang +6 位作者 pingping xu Jicheng Yan Yuzhong Zhang Hainan Su Chengjun Sun Qiang Lu Weizhi Liu 《Bioactive Materials》 SCIE 2022年第4期504-514,共11页
Antioxidant biomaterials have attracted much attention in various biomedical fields because of their effective inhibition and elimination of reactive oxygen species(ROS)in pathological tissues.However,the difficulty i... Antioxidant biomaterials have attracted much attention in various biomedical fields because of their effective inhibition and elimination of reactive oxygen species(ROS)in pathological tissues.However,the difficulty in ensuring biocompatibility,biodegradability and bioavailability of antioxidant materials has limited their further development.Novel bioavailable antioxidant materials that are derived from natural resources are urgently needed.Here,an integrated multi-omics method was applied to fabricate antioxidant biomaterials.A key cysteine-rich thrombospondin-1 type Ⅰ repeat-like(TSRL)protein was efficiently discovered from among 1262 adhesive components and then used to create a recombinant protein with a yield of 500 mg L^(-1).The biocompatible TSRL protein was able to self-assemble into either a water-resistant coating through Ca^(2+)-mediated coordination or redox-responsive hydrogels with tunable physical properties.The TSRL-based hydrogels showed stronger 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical scavenging rates than glutathione(GSH)and ascorbic acid(Aa)and protected cells against external oxidative stress significantly more effectively.When topically applied to mice skin,TSRL alleviated epidermal hyperplasia and suppressed the degradation of collagen and elastic fibers caused by ultraviolet radiation B(UVB)irradiation,confirming that it enhanced antioxidant activity in vivo.This is the first study to successfully characterize natural antioxidant biomaterials created from marine invertebrate adhesives,and the findings indicate the excellent prospects of these biomaterials for great applications in tissue regeneration and cosmeceuticals. 展开更多
关键词 Sessile marine organisms Antioxidant biomaterials Water-resistant coatings Redox-responsive hydrogels PHOTOAGING
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Plant above-ground biomass and litter quality drive soil microbial metabolic limitations during vegetation restoration of subtropical forests
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作者 Shuo Zhang Ying-Ping Wang +8 位作者 Xi Fang Jinlei Chen Nannan Cao pingping xu Mengxiao Yu Xin Xiong Xiangping Tan Qi Deng Junhua Yan 《Soil Ecology Letters》 CSCD 2023年第2期103-115,共13页
Changes in litter quality(carbon:nitrogen,C:N)and above-ground biomass(AGB)following vegetation restoration significantly impact soil physicochemical properties,yet their effects on soil microbial metabolic limitation... Changes in litter quality(carbon:nitrogen,C:N)and above-ground biomass(AGB)following vegetation restoration significantly impact soil physicochemical properties,yet their effects on soil microbial metabolic limitations remain unclear.We measured litter quality,AGB,soil physicochemical properties,and extracellular enzyme activity(EEA)along a vegetation restoration gradient(7,14,49,70 years,and nearly climax evergreen broadleaved forests)in southern China.We also evaluated soil microbial metabolic limitations by a vector analysis of the EEA.Results revealed the soil microbial metabolisms were co-limited by C and phosphorus(P).The microbial C limitation initially decreased(before 14 years)and then increased,while the microbial P limitation initially increased(before 49 years)and then decreased.Partial least squares path modeling(PLS-PM)showed that the microbial C limitation was mainly attributed to microbial C use efficiency induced by litter quality,suggesting that microorganisms may transfer cellular energy between microbial growth and Cacquiring enzyme production.The microbial P limitation was primarily correlated with AGB-driven change in soil elements and their stoichiometry,highlighting the importance of nutrient stoichiometry and balance in microbial metabolism.The shifts between microbial C and P limitations and the strong connections of plant–soil-microbe processes during vegetation restoration revealed here will provide us with helpful information for optimal management to achieve forest restoration success. 展开更多
关键词 Extracellular enzymatic stoichiometry Microbial metabolic limitations Above-ground biomass Litter quality Vegetation restoration Subtropic
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Effect of ultrasound power on extraction kinetic model,and physicochemical and structural characteristics of collagen from chicken lung
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作者 Ye Zou Heng Yang +5 位作者 Xinxiao Zhang pingping xu Di Jiang Muhan Zhang Weimin xu Daoying Wang 《Food Production, Processing and Nutrition》 2020年第1期10-21,共12页
The effects of ultrasound power on extraction kinetic model,and physicochemical and structural characteristics of collagen from chicken lung were studied.Ultrasound power caused a significant increase in extraction ra... The effects of ultrasound power on extraction kinetic model,and physicochemical and structural characteristics of collagen from chicken lung were studied.Ultrasound power caused a significant increase in extraction rate and equilibrium concentration,with the maximum extraction yield(31.25%)at 150 W.The experimental data were consistent with the predicted ones in this empirical equation,in which the percentage error differences was 0.026–4.159%.Besides,ultrasound treatment did not affect their triple-helical structure.The thermal stability of pepsin-soluble collagen by ultrasound pretreatment(UPSC)was higher,due to the higher imino acid content(20.76%).UPSC also exhibited better solubility and fibril forming capacity.Overall,the kinetic model of UPSC from chicken lung could serve the purpose of obtaining collagen,which displayed a potential alternative source to mammal collagens for application in food,biomaterials and biomedical fields. 展开更多
关键词 Extraction kinetics Chicken lung Pepsin-soluble collagen Ultrasound pretreatment
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