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Communications in Computational Physics 2021年第6期30卷 124-143页

作者： Cheng wang pengtao Sun School of Mathematical Sciences Tongji UniversityShanghai 200092China Department of Mathematical Sciences University of Nevada Las Vegas4505Maryland ParkwayLas VegasNV 89154USA

.In this paper,an augmented Lagrangian Uzawa iterative method is developed and analyzed for solving a class of double saddle-point systems with semidefinite(2,2)block.Convergence of the iterativemethod is proved under the assumption that the double saddle-point problem exists a unique solution.An application of the iterative method to the double saddle-point systems arising from the distributed Lagrange multiplier/fictitious domain(DLM/FD)finite element method for solving elliptic interface problems is also presented,in which the existence and uniqueness of the double saddle-point system is guaranteed by the analysis of the DLM/FD finite element method.Numerical experiments are conducted to validate the theoretical results and to study the performance of the proposed iterative method.

关键词： Double saddle-point problem augmented Lagrangian Uzawa method elliptic interface problem distributed Lagrange multiplier/fictitious domain(DLM/FD)method

Modelling the response of larch growth to age,density,and elevation and the implications for multifunctional management in northwest China

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林业研究:英文版 2023年第5期34卷 1423-1436页

作者： Ao Tian Yanhui wang Ashley A.Webb pengtao Yu Xiao wang Zebin Liu Institute of Mountain Resource of Guizhou Province Guiyang 550001People’s Republic of China Ecology and Nature Conservation Institute Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland AdministrationChinese Academy of ForestryBeijing 100091People’s Republic of China WaterNSW TamworthNSWAustralia

Plantations of Rupprecht's larch(Larix principis-rupprechtii)have been widely established in the drylands of northwest and north China under traditional fastgrowing plantation management strategies.These strategies and the long-term logging ban have led to over-populated stands with lower structural and functional stability,less economic benefit and higher water consumption.To guide the sustainable management of larch plantations,field surveys and historical data compilation were undertaken in the Liupan Mountains of northwest China.The main influencing factors(stand structure and site condition)and their effects on mean tree height,mean DBH and timber volumes were determined based on up-boundary line analysis.Tree growth models coupling the effects of tree age,stand density,and elevation were established.Both height and DBH markedly increased initially and then slowly with tree age,decreased with stand density,and showed unimodal change with elevation.The coupled growth models accounted for72-78%of the variations in tree height,DBH and timber growth.Recommendations for future plantation management are:(1)prolong the rotation to at least 60 years to produce large-diameter,high-quality timber and maintain greater carbon stocks;(2)zone the target functions of stands by elevation;and,(3)reduce stand density for balanced supply of multiple ecosystem services.The growth models developed can predict growth response of larch plantations to density alteration under given ages and elevations,and assist the transformation from traditional management for maximum timber production to site-specific and multifunctional management with longer rotations and moderate tree density.

关键词： Larch plantations Coupled growth model Influencing factors Age Density Elevation

Environmental and canopy conditions regulate the forest floor evapotranspiration of larch plantations

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Forest Ecosystems 2022年第5期9卷 606-616页

作者： Zebin Liu Yanhui wang pengtao Yu Lihong Xu Songping Yu Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China School of Soil and Water Conservation Beijing Forestry UniversityBeijing100083China

Background:Integrated forest-water management focusing on forest-water coordination is an important way to alleviate water use conflicts among forests and other sectors in vast dryland regions.Forest floor evapotranspiration(FE),which is an important component of forest evapotranspiration,accounts for a large proportion of the water consumed in arid forests.Elucidating how environmental and canopy conditions impact FE has important significance for guiding integrated forest-water management in a changing environment.Methods:The microlysimeter(ML)-measured evapotranspiration(FE_(ML)),reference evapotranspiration(ET_(o)),volumetric soil moisture(VSM),and canopy leaf area index(LAI)were monitored in a Larix principis-rupprechtii plantation located in the semi-humid Liupan Mountains of Northwest China in 2019(June–September)and 2021(May–September).The response functions of the FE coefficient(the ratio of daily FEML to ET_(o))to the individual factors of VSM and LAI were determined using upper boundary lines of scatter diagrams of measured data.The framework of the daily FE(FE_(ML))model was established by multiplying the response functions to individual factors and then calibrated and validated using measured data to assess the FE response to environmental and canopy conditions.Results:(1)The FE coefficient increased first rapidly and then slowly with rising VSM but decreased slowly with rising LAI.(2)The simple daily FE(FE_(ML))model developed by coupling the impacts of ET_(o),LAI,and VSM in this study performed well for predicting FE.(3)The impacts of ET_(o),LAI,and VSM were quantified using the FE(FE_(ML))model,e.g.,at a given VSM,the impact of ETo on FE increased obviously with decreasing LAI;at a given ET_(o),the impact of LAI on FE increased with rising VSM.(4)In the two study years,when directly using the microlysimeter measurement,the real FE on the forest floor was overestimated when the VSM in microlysimeters was above 0.215 but underestimated below 0.215 due to the difference in VSM from the forest floor.T

关键词： Larch plantation Forest floor evapotranspiration Reference evapotranspiration Soil water content Canopy structure

3D printing of osteocytic Dll4 integrated with PCL for cell fate determination towards osteoblasts in vitro

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Bio-Design and Manufacturing 2022年第3期5卷 497-511页

作者： pengtao wang Xiaofang wang Bo wang Xian Li Zhengsong Xie Jie Chen Tasuku Honjo Xiaolin Tu Laboratory of Skeletal Development and Regeneration Institute of Life SciencesChongqing Medical UniversityChongqing 400016China Medical Data Science Academy Chongqing Medical UniversityChongqing 400016China Department of Immunology and Genomic Medicine Graduate School of MedicineKyoto UniversityYoshida Konoe-choSakyo-kuKyoto 606-8501Japan

Since 3D printed hard materials could match the shape of bone,cell survival and fate determination towards osteoblasts in such materials have become a popular research target.In this study,a scaffold of hardmaterial for 3D fabrication was designed to regulate developmental signal(Notch)transduction guiding osteoblast differentiation.We established a polycaprolactone(PCL)and cell-integrated 3D printing system(PCI3D)to reciprocally print the beams of PCL and cell-laden hydrogel for a module.This PCI3D module holds good cell viability of over 87%,whereas cells show about sixfold proliferation in a 7-day culture.The osteocytic MLO-Y4 was engineered to overexpress Notch ligand Dll4,making up 25%after mixing with 75%stromal cells in the PCI3D module.Osteocytic Dll4,unlike other delta-like family members such as Dll1 or Dll3,promotes osteoblast differentiation and themineralization of primary mouse and a cell line of bone marrow stromal cells when cultured in a PCI3D module for up to 28 days.Mechanistically,osteocytic Dll4 could not promote osteogenic differentiation of the primary bone marrow stromal cells(BMSCs)after conditional deletion of the Notch transcription factor RBPjκby Cre recombinase.These data indicate that osteocytic Dll4 activates RBPjκ-dependent canonical Notch signaling in BMSCs for their oriented differentiation towards osteoblasts.Additionally,osteocytic Dll4 holds a great potential for angiogenesis in human umbilical vein endothelial cells within modules.Our study reveals that osteocytic Dll4 could be the osteogenic niche determining cell fate towards osteoblasts.This will open a new avenue to overcome the current limitation of poor cell viability and low bioactivity of traditional orthopedic implants.

关键词： Integrated 3D printing PCL scaffold Cell-laden hydrogel Osteocytic Dll4 Bone marrow stromal cell Osteoblast differentiation Cell viability in hard material RBPjκ Notch signaling

Impacts of environmental and canopy conditions on the nighttime sap flow of larch plantations in the Liupan Mountains,China

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林业研究:英文版 2023年第6期34卷 1927-1940页

作者： Songping Yu Jianbin Guo Zebin Liu Yanhui wang Lihong Xu pengtao Yu Liang He School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083People’s Republic of China Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China

Nighttime sap flow(Q_(n))is an important physiological activity under which trees manage drought stress.An in-depth understanding of the characteristics of Q_(n)and its response to environmental and canopy conditions are of significance for arid area forest and water management.This study measured daily sap flow(Q_(s))of a Larix principis-rupprechtii plantation in the Liupan Mountains,northwest China during the 2017-2019 growing seasons,and separated Q_(s)into daytime sap flow(Qd)and Q_(n).Meteorological conditions(reference evapotranspiration,ETref),canopy structure(leaf area index,LAI),and soil moisture(relative soil water content,RSWC)were considered as the main biophysical factors affecting Q_(n).The structural equation model and upper boundary line method determined the effects of compound and single factors on Q_(n)The daily mean Q_(n)values during the growing seasons in 2017,2018,and 2019 were 0.024,0.026,and 0.030 mm d-1,accounting for 6.2,11.2,and 10.1%of Q_(s),respectively.Q_(n)at different canopy development phases(leaf expanding,LG;leaf expanded,LD;and defoliation,DF)over three years was LD>LG>DF.Q_(n)increased with increasing ETref,whereas the ratio of Q_(n)to Q_(s)decreased.Q_(n)did not show regular variation in the three-year growing seasons under different soil moisture conditions.ETrefand LAI mainly controlled Q_(n)by affecting Qd,whereas RSWC had no significant effect on Q_(n).Q_(n)had a positive and linear relationship with LAI and a quadratic relationship with ETref.Both explained 40%of variation in Q_(n)Meteorological and canopy conditions are important factors affecting Q_(n)on the semi-humid study site.The application of the Q_(n)model coupled with the impact of ETrefand LAI furthers understanding of the impacts of climate and forest structure change on Q_(n).

关键词： Nighttime sap flow Reference evapotranspiration Leaf area index Soil moisture Multifactor impact

SnO/SnO_(2) heterojunction:an alternative candidate for sensing NO_(2) with fast response at room temperature

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Frontiers of Materials Science 2022年第3期16卷 193-202页

作者： pengtao wang Wanyin GE Xiaohua JIA Jingtao HUANG Xinmeng ZHANG Jing LU School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi'an 710021China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The SnO_(2)-based family is a traditional but important gas-sensitive material.However,the requirement for high working temperature limits its practical application.Much work has been done to explore ways to improve its gas-sensing performance at room temperature(RT).For this report,SnO_(2),SnO,and SnO/SnO_(2) heterojunction was successfully synthesized by a facile hydrothermal combined with subsequent calcination.Pure SnO_(2) requires a high operating temperature(145℃),while SnO/SnO_(2) heterojunction exhibits an excellent performance for sensing NO_(2) at RT.Moreover,SnO/SnO_(2) exhibits a fast response,of 32 s,to 50 ppm NO_(2) at RT(27℃),which is much faster than that of SnO(139 s).The superior sensing properties of SnO/SnO_(2) heterojunction are attributed to the unique hierarchical structures,large number of adsorption sites,and enhanced electron transport.Our results show that SnO/SnO_(2) heterojunction can be used as a promising high-performance NO_(2) sensitive material at RT.

关键词： SnO SnO_(2) heterostructure NO_(2) roomtemperature

全民阅读背景下数字阅读供给的自治理机制设计

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出版发行研究 2024年第4期 18-24,90页

作者：王鹏涛南京大学信息管理学院

在全民阅读发展过程中,拓展阅读对象的种类与范围固然重要,但如何保障这些出版物尤其是数字阅读供给的质量与可靠性,已成为亟须解决的问题。文章构建了数字阅读供给质量的自治理机制,以适应数字时代的新趋势,解决当前阅读推广中面临的... 详细信息

在全民阅读发展过程中,拓展阅读对象的种类与范围固然重要,但如何保障这些出版物尤其是数字阅读供给的质量与可靠性,已成为亟须解决的问题。文章构建了数字阅读供给质量的自治理机制,以适应数字时代的新趋势,解决当前阅读推广中面临的新问题。该机制强调通过制定明确的规则和标准、建立多方协同的评估体系、确保全程信息公开透明、鼓励用户反馈与参与,以及公布违约责任和惩罚措施等方式,全面提升阅读推广的效果,确保公民能够获取优质、安全的数字阅读资源,推动全民阅读工作深入发展,促进出版业以及公共文化事业繁荣兴盛。

关键词：全民阅读数字出版物自治理机制

A novel decellularized matrix of Wnt signaling-activated osteocytes accelerates the repair of critical-sized parietal bone defects with osteoclastogenesis, angiogenesis, and neurogenesis

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Bioactive Materials 2023年第3期21卷 110-128页

作者： Xiaofang wang Yufei Ma Jie Chen Yujiao Liu Guangliang Liu pengtao wang Bo wang Makoto M.Taketo Teresita Bellido Xiaolin Tu Laboratory of Skeletal Development and Regeneration Institute of Life SciencesChongqing Medical UniversityChongqing400016China Department of Pharmacology Graduate School of MedicineKyoto UniversityKyoto606-8501Japan Department of Physiology and Cell Biology University of Arkansas for Medical SciencesLittle RockAR72223USA Department of Anatomy and Cell Biology Indiana University School of MedicineIndianapolisIN46202USA

Cell source is the key to decellularized matrix(DM)strategy.This study compared 3 cell types,osteocytes with/without dominant active Wnt/β-catenin signaling(daCO and WTO)and bone marrow stromal cells(BMSCs)for their DMs in bone repair.Decellularization removes all organelles and>95%DNA,and retained>74%collagen and>71%GAG,maintains the integrity of cell basement membrane with dense boundaries showing oval and honeycomb structure in osteocytic DM and smooth but irregular shape in the BMSC-DM.DM produced higher cell survival rate(90%)and higher proliferative activity.In vitro,daCO-DM induces more and longer stress fibers in BMSCs,conducive to cell adhesion,spreading,and osteogenic differentiation.8-wk after implantation of the critical-sized parietal bone defect model,daCO-DM formed tight structures,composed of a large number of densely-arranged type-I collagen under polarized light microscope,which is similar to and integrated with host bone.BV/TV(>54%)was 1.5,2.9,and 3.5 times of WTO-DM,BMSC-DM,and none-DM groups,and N.Ob/T.Ar(3.2×10^(2)/mm^(2))was 1.7,2.9,and 3.3 times.At 4-wk,daCO-DM induced osteoclastogenesis,2.3 times higher than WTO-DM;but BMSC-DM or none-DM didn't.daCO-DM increased the expression of RANKL and MCSF,Vegfa and Angpt1,and Ngf in BMSCs,which contributes to osteoclastogenesis,angiogenesis,and neurogenesis,respectively.daCO-DM promoted H-type vessel formation and nerve markersβ3-tubulin and NeuN expression.Conclusion:daCO-DM produces metabolic and neurovascularized organoid bone to accelerate the repair of bone defects.These features are expected to achieve the effect of autologous bone transplantation,suitable for transformation application.

关键词： Decellularized matrix Osteocyte Wnt signaling 3D printing Regenerative repair Metabolic and neurovascular organoid bone

Confining sulfur in sandwich structure of bamboo charcoal and aluminum fluoride(BC@S@AlF3) as a long cycle performance cathode for Li-S batteries

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Journal of Materials Science & Technology 2020年第20期52卷 159-166页

作者： Zhenya Luo Xiao wang Weixin Lei pengtao Xia Yong Pan National-Provincial Laboratory of Special Function Thin Film Materials Xiangtan UniversityXiangtanHunan 411105China School of Materials Science and Engineering Xiangtan UniversityXiangtanHunan 411105China

The ’shuttle effect’ of polysulfide causing rapid capacity fade and low coulo mbic efficiency of high ene rgy storage lithium-sulfur(Li-S) batteries.Herein,a sandwich structure of bamboo charcoal/sulfur coating by aluminum fluoride(BC@S@AlF3) composites is designed and fabricated for the first time.The as-designed cathode exhibited excellent electrochemical properties and stable capacity retention.The initial capacity reaches 1119 mA h/g and the capacity after 100 cycles is 869 mA h/g at 0.5 C,which is much stable than that of composite materials without bamboo charcoal or AlF3 coating.Moreover,the BC@S@AlF3 cathode presents excellent long-term capacity stability with a capacity decay of 0.073% per cycle during 500 charge/discharge cycles at 1 C,offering a potential for use in high energy Li-S batteries.The physical confinement,chemical ancho ring,and catalysis conversion for active sulfur are achieved simultaneously with the AlF3 coating and bamboo charcoal core with porous structure.

关键词： AlF3 coating Strong polarity Sulfur immobilizers Lithium-sulfur batteries

Seasonal Responses of Net Primary Productivity of Vegetation to Phenological Dynamics in the Loess Plateau, China

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Chinese Geographical Science 2022年第2期32卷 340-357页

作者： HAN Hongzhu BAI Jianjun MA Gao YAN Jianwu wang Xiaohui TA Zhijie wang Pengtao School of Tourism&Research Institute of Human Geography Xi'an International Studies UniversityXi'an 710128China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China China Academy of Space Technology-Xi'an Xi'an 710000China School of Humanities and Social Sciences Xi'an University of Posts and TelecommunicationsXi'an 710121China

With global warming, the great changes in the patterns of plant growth have occurred. The conditions in early spring and late autumn have changed the process of vegetation photosynthesis, which are expected to have a significant impact on net primary productivity(NPP) and affect the global carbon cycle. Currently, the seasonal response characteristics of NPP to phenological changes in dryland ecosystems are still not well defined. This article calibrated and analyzed the normalized difference vegetation index(NDVI)time series of Advanced Very-High-Resolution Radiometer(AVHRR) data from 1982 to 2015 in the Loess Plateau, China. The spatial and temporal distributions of vegetation phenology and NPP in the Loess Plateau under semihumid and semiarid conditions were investigated. The seasonal variation in the NPP response to vegetation phenology under the climate change was also analyzed. The results showed that, different from the northern forest, there was distinct spatial heterogeneity in the effect of climate change on the dynamic change in vegetation growth in the Loess Plateau: 1) an advance of the start of the growing season(SOS) and a delay of the end of the growing season(EOS) significantly increased the NPP in spring and autumn, respectively, in the humid southeast;2) in the arid northwest, the NPP did not significantly increase in spring and autumn but significantly decreased in summer.

关键词： climate change normalized difference vegetation index phenology net primary productivity Loess Plateau,China