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Depth Distributions of Belowground Production, Biomass and Decomposition in Restored Tallgrass Prairie

Pedosphere 2019年第4期29卷 457-467页

作者： Adam C.VON HADEN Mathew E.DORNBUSH Environmental Science and Policy Graduate Program University of Wisconsin- Green Bay Green Bay WI 54311 (USA) great Lakes Bioenergy research center University of Wisconsin-Madison Madison WI 53726 (USA) Department of Natural and Applied Sciences University of Wisconsin- Green Bay Green Bay WI 54311 (USA)

Grasslands store large stocks of soil organic carbon(SOC) in the subsoil, but our knowledge of belowground processes becomes less robust with depth. Vertically explicit SOC models typically assume that the depth distribution of belowground production follows the depth distribution of belowground biomass, but this assumption has not been tested. In addition to the effects of soil temperature and moisture on decomposition, some vertically explicit SOC models implement an intrinsic decrease in belowground decomposition with depth, yet this effect has rarely been observed empirically. We simultaneously measured the depth distributions of belowground biomass, production, and litter decomposition to assess whether belowground biomass depth distributions were suitable predictors of belowground production and whether belowground decomposition decreased with soil profile depth. We found that live and total(live +dead) belowground biomass was distributed relatively more shallowly than total belowground production, and thus total belowground biomass was a biased predictor of the vertical distribution of belowground production. The depth distribution of live roots < 2 mm in diameter was found to be the best predictor of total belowground production depth distribution. Using an intact decay core method,we found that belowground litter decomposition decreased by 49% from 0–10 to 30–40 cm depth, and model-simulated effects of soil temperature and moisture accounted for only 9% of the observed decrease with depth. Vertically explicit SOC models can be improved with more accurate empirical belowground production depth distribution estimates, but depth-specific decomposition rates currently implemented in SOC models are necessary to explain observed decreases in belowground litter decay with depth.

关键词： carbon decomposition litter decay model simulation roots soil organic carbon soil organic matter temperate grassland vertical rooting distributions

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Localization of the Arabidopsis senescence- and Cell Death-Associated BFN1 Nuclease： From the ER to Fragmented Nuclei

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Molecular Plant 2011年第6期4卷 1062-1073页

作者： Sarit Farage-Barhom Shaul Burd Lilian Sonego Ana Mett Eduard Belausov David Gidoni Amnon Lers Department of Postharvest Science of Fresh Produce Volcani Center Agricultural Research Organization Bet Dagan 50250 Israe Faculty of Life Science Bar Ilan University Ramat Gan Israel Department of Vegetable research Volcani Center Agricultural Research Organization Bet Dagan 50250 Israel Department of Ornamental Horticulture Volcani Center Agricultural Research Organization Bet Dagan 50250 Israe

Plant senescence- or PCD-associated nucleases share significant homology with nucleases from different organisms. However, knowledge of their function is limited. Intracellular localization of the Arabidopsis senescence- and PCD-associated nuclease BFN1 was investigated. Analysis of BFN1-GFP localization in transiently transformed tobacco protoplasts revealed initial localization in filamentous structures spread throughout the cytoplasm, which then clustered around the nuclei as the protoplasts senesced. These filamentous structures were identified as being of ER origin. In BFN1- GFP-transgenicArabidopsis plants, similar localization of BFN1-GFP was observed in young leaves, that is, in filamentous structures that reorganized around the nuclei only in senescing cells. In late senescence, BFN1-GFP was localized with fragmented nuclei in membrane-wrapped vesicles. BFNI＇s postulated function as a nucleic acid-degrading enzyme in senescence and PCD is supported by its localization pattern. Our results suggest the existence of a dedicated compartment mediating nucleic acid degradation in senescence and PCD processes.

关键词： BFN1 endoplasmic reticulum nuclease nuclear DNA programmed cell death senescence sub-cellular localization.

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DNA-PK inhibition by M3814 enhances chemosensitivity in non-small cell lung cancer

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Acta Pharmaceutica Sinica B 2021年第12期11卷 3935-3949页

作者： Manni Wang Siyuan Chen Yuquan Wei Xiawei Wei Laboratory of Aging research and Cancer Drug Target State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610000China

A significant proportion of non-small cell lung cancer(NSCLC) patients experience accumulating chemotherapy-related adverse events,motivating the design of chemosensitizating *** main cytotoxic damage induced by chemotherapeutic agents is DNA double-strand breaks(DSB).It is thus conceivable that DNA-dependent protein kinase(DNA-PK) inhibitors which attenuate DNA repair would enhance the anti-tumor effect of *** present study aims to systematically evaluate the efficacy and safety of a novel DNA-PK inhibitor M3814 in synergy with chemotherapies on *** identified increased expression of DNA-PK in human NSCLC tissues which was associated with poor prognosis.M3814 potentiated the anti-tumor effect of paclitaxel and etoposide in A549,H460 and H1703 NSCLC cell *** the four combinations based on two NSCLC xenograft models and two chemotherapy,we also observed tumor regression at tolerated doses in ***,we identified a P53-dependent accelerated senescence response by M3814 following treatment with paclitaxel/*** present study provides a theoretical basis for the use of M3814 in combination with paclitaxel and etoposide in clinical practice,with hope to aid the optimization of NSCLC treatment.

关键词： M3814 Paclitaxel Etoposide DNA-dependent protein kinase Non-small cell lung cancer DNA repair Cell senescence Chemosensitization

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Wrinkle-crease interaction behavior simulation of a rectangular membrane under shearing

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Acta Mechanica Sinica 2011年第4期27卷 550-558页

作者： C.-G.Wang.H.-F.Tan.X.-D.He center for Composite Materials,Harbin Institute of Technology,150080 Harbin,China Post-doctoral research center in Material Science and Engineering,Harbin Institute of Technology,150001 Harbin,China center for Composite Materials Harbin Institute of Technology Harbin China Post-doctoral research center in Material Science and Engineering Harbin Institute of Technology Harbin China

Wrinkling analysis of a rectangular membrane with a single crease under shearing is performed to understand the wrinkle-crease interaction behaviors. The crease is considered by introducing the residual stresses from creasing and the effective modulus into the baseline configuration with assumed circular cross-sectional crease geometry. The wrinkling analysis of the creased membrane is then performed by using the direct perturb-force （DP） simulation technique which is based on our modified displacement components （MDC） method. Results reveal that the crease may influence the stress transfer path in the membrane and further change the wrinkling direction. The crease appears to improve the bending stiffness of the membrane which has an effective resistance on the wrinkling evolution. The effects of the crease orientation on wrinkle-crease interaction are studied toward the end of this paper. The results show that the wrinkling amplitude, wavelength, and direction increase as the crease orientation increases, and the wrinkling number decreases with the increasing crease orientation. These results will be of great benefit to the analysis and the control of the wrinkles in the membrane structures.

关键词： Membrane structure - Wrinkle-crease interac-tion Membrane wrinkling Creased membrane

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PagMYB128 regulates secondary cell wall formation by direct activation of cell wall biosynthetic genes during wood formation in poplar

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Journal of Integrative Plant Biology 2024年第8期66卷 1658-1674页

作者： Yuanyuan Hao Fachuang Lu Seung-Won Pyo Min-Ha Kim Jae-Heung Ko Xiaojing Yan John Ralph Quanzi Li State Key Laboratory of Tree Genetics and Breeding Chinese Academy of ForestryBeijing 100091China Department of Biochemistry and DOE great Lakes Bioenergy research center Wisconsin Energy InstituteUniversity of Wisconsin-MadisonWisconsin 53726USA Department of Plant&Environmental New Resources Kyung Hee UniversityYongin 17104Korea

The biosynthesis of cellulose,lignin,and hemicelluloses in plant secondary cell walls(SCWs)is regulated by a hierarchical transcriptional regulatory *** network features orthologous transcription factors shared between poplar and Arabidopsis,highlighting a foundational similarity in their genetic ***,knowledge on the discrepant behavior of the transcriptional-level molecular regulatory mechanisms between poplar and Arabidopsis remains *** this study,we investigated the function of PagMYB128 during wood formation and found it had broader impacts on SCW formation compared to its Arabidopsis ortholog,*** poplar trees overexpressing PagMYB128 exhibited significantly enhanced xylem development,with fiber cells and vessels displaying thicker walls,and an increase in the levels of cellulose,lignin,and hemicelluloses in the *** contrast,plants with dominant repression of PagMYB128 demonstrated the opposite *** sequencing and reverse transcription–quantitative polymerase chain reaction showed that PagMYB128 could activate SCW biosynthetic gene expression,and chromatin immunoprecipitation along with yeast one-hybrid,and effector–reporter assays showed this regulation was *** analysis revealed that PagSND1(SECONDARY WALL-ASSOCIATED NAC-DOMAIN PROTEIN1)directly regulates PagMYB128 but not cell wall metabolic genes,highlighting the pivotal role of PagMYB128 in the SND1-driven regulatory network for wood development,thereby creating a feedforward loop in SCW biosynthesis.

关键词： cellulose hemicellulose lignin PagMYB128 Populus transcription factor wood formation

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Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler

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Chinese Journal of Chemical Engineering 2024年第4期68卷 203-215页

作者： Chen Han Youmin Situ Huaxing Zhu Jianliang Xu Zhenghua Dai Guangsuo Yu Haifeng Liu National Energy Coal Gasification Technology research and Development center East China University of Science and TechnologyShanghai 200237China Shanghai Engineering research center of Coal Gasification East China University of Science and TechnologyShanghai 200237China

Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation *** the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was *** modified model shows high accuracy in *** computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial *** with Smith's model,the temperature decay along the axial direction calculated by the modified model is *** components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.

关键词： Radiant syngas cooler Weighted-sum-of-gray-gases model Numerical simulation Particle radiation

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Maternal mental health and well-being during the COVID-19 pandemic in Beijing, China

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World Journal of Pediatrics 2021年第3期17卷 280-289页

作者： Zhuang Wei Ming-Yue Gao Mary Fewtrell Jonathan Wells Jin-Yue Yu Department of Child Healthcare Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Population Policy and Practice Research and Teaching DepartmentUCL Great Ormond Street Institute of Child Health30 Guilford StreetLondon WC1N 1EHUK

Background The aim of this study is to evaluate the impact of the coronavirus disease 2019(COVID-19)pandemic on breastfeeding women and to identify predictors of maternal mental health and *** Mothers aged≥18 years with a breast-fed infant≤18 months of age during the COVID-19 pandemic in Beijing,China,completed a *** analysis of lockdown consequences was performed and predictors of these outcomes were examined using stepwise linear *** Of 2233 participants,29.9%,20.0%and 34.7%felt down,lonely,and worried,respectively,during the lockdown;however,85.3%felt able to *** maternal mental health was predicted by maternal(younger age,higher education)and infant(older age,lower gestation)characteristics,and social circumstances(husband unemployed or working from home,receiving advice from family,having enough space for the baby,living close to a park or green space).Conversely,better maternal mental health was predicted by higher income,employment requiring higher qualifications,more personal space at home,shopping or walking>once/week and lack of impact of COVID-19 on job or *** with higher education,more bedrooms,fair division of household chores and attending an online mother and baby group>once/week reported better *** The findings highlight maternal characteristics and circumstances that predict poorer mental health and reduced coping which could be used to target interventions in any future public health emergencies requiring social restrictions.

关键词： Coping Coronavirus disease 2019 Maternal health Mental health Postpartum

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Grain refinement and orientation of AZ31B magnesium alloy in hot flow forming under different thickness reductions

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Journal of Materials Science & Technology 2018年第7期34卷 1091-1102页

作者： Yalian Zhang Fenghua Wang Jie Dong Li Jin Conghui Liu Wenjiang Ding National Engineering research center of Light Alloy Net Forming & State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai Light Alloy Net Forming National Engineering research center Co. Ltd

An analysis of the hot flow forming of Mg-3.0Al-l.0Zn-0.3Mn （AZ31B） alloy was conducted by experiments and numerical simulations. The effects of different thickness reductions on the microstructure and mechanical properties were investigated at a temperature of 693 K, a spindle speed of 800 rev/min and a feed ratio of 0.1 mm/rev. Thickness reductions have great influence on the uniformity of microstructure along the radial direction （RD） and the grain sizes become refined and uniform when the thickness reduction reaches 45%. The c-axes of most grains are approximately parallel to the RD, with a slight inclination towards the axial direction （AD）. The best mechanical properties with UTS of 280 MPa and YS of 175 MPa near the outer surface while 266 MPa and 153 MPa near the inner surface have been achieved due to grain refinement and texture. Moreover, the material flow behavior and stress/strain distributions for singlepass reductions were studied using the ABAQUS/Explicit software. The calculated results indicate that the materials mainly suffer from triaxial compressive stresses and undergo compressive plastic strain in RD and tensile strains in other directions. The higher stress and strain rate near the outer surface lead to more refined grains than that of other regions along the RD, whereas the orientation of the maximum principal compressive stress leads to a discrepancy of the grain orientations in RD.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： AZ31B Hot flow forming Grain refinement Texture

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Tuning of Multi-stability Profile and Transition Sequence of Stacked Miura-Origami Metamaterials

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Acta Mechanica Solida Sinica 2023年第4期36卷 554-568页

作者： Haiping Wu Hongbin Fang Institute of AI and Robotics Fudan UniversityShanghai 200433China MOE Engineering research center of AI and Robotics Fudan UniversityShanghai 200433China Shanghai Engineering research center of AI and Robotics Fudan UniversityShanghai 200433China

Multi-stable origami structures and metamaterials possess unique advantages and could exhibit multiple stable three-dimensional configurations,which have attracted widespread research interest and held promise for applications in many *** a great deal of attention has been paid to the design and application of multi-stable origami structures,less knowledge is available about the transition sequence among different stable configurations,especially in terms of the fundamental mechanism and the tuning *** fill this gap,with the multi-stable dual-cell stacked Miura-ori chain as a platform,this paper explores the rules that govern the configuration transition and proposes effective methods for tuning the transition ***,by correlating the energy evolution,the transition paths,and the associated force-displace-ment profiles,we find that the critical extension/compression forces of the component cells play a critical role in governing the transition ***,we summarize the rules for predicting the transition sequence:the component cell that first reaches the critical force during quasi-static extension or compression will be the first to undergo a configuration *** on these findings,two methods,i.e.,a design method based on crease-stiffness assignment and an online method based on internal pressure regulation,are proposed to tune the stability profile and the transition sequence of the multi-stable origami *** crease-stiffness design approach,although effective,cannot be employed for online tuning once the prototype has been *** pressure-based approach,on the other hand,has been shown experimentally to be effective in adjusting the constitutive force-displacement profiles of the component cells and,in turn,tuning the transition sequence according to the summarized *** results of this study will advance the state of the art of origami mechanics and promote the engineering applications of mu

关键词： Origami metamaterial Bi-stability Origami mechanics Pneumatic origami Snap-through transition

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Coating of microbially produced calcium carbonate onto stone materials

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Science China(Technological Sciences) 2015年第2期58卷 266-272页

作者： ZHU Wen Kun MU Tao ZHANG You Kui DUAN Tao LUO Xue Gang Engineering research center of Biomass Materials Ministry of Education Southwest University of Science and Technology China Academy of Engineering Physics Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and Technology and Research Center of Laser FusionCAEP

The coatings of microorganism-induced calcium carbonate onto the stone surface carried out by using both of the immersion method and coating method were investigated. Various analysis and testing techniques such as scanning electron micrograph （SEM） and X-ray diffraction （XRD） were used to characterize the deposited mineral layer. The adhesive property, acid re- sistance, frost resistance, light and aging resistance, water adsorption and permeability were investigated in detail. The results showed that both immersion method and coating method could produce calcium carbonate granules with sizes ranging from 1 to 10 pm and form a layer of dense mineralization membrane which is about 50 to 100 pm thick. Immersion method was more efficient than coating method. The large cohesive force between calcium carbonate layer and stone materials could improve the acid rain resistance as well as excellent heat tolerance, frost resistance and light aging resistance. The coating process could not only help the stone materials maintain its original permeability with the aid of calcium carbonate layers but also improve the penetration resistance significantly. Therefore, this type of technology shows a great potential in the protection of stone relics.

关键词： microorganism microbially induced deposited-layer stone materials

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