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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses

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Journal of Forestry Research 2024年第2期35卷 42-53页

作者： Ting Wang Qing Xu Beibei Zhang Deqiang Gao Ying Zhang jing jiang Haijun Zuo 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 College of Agronomy and Agricultural Engineering Liaocheng UniversityLiaocheng 252000People’s Republic of China Department of Forest and Conservation Sciences Faculty of ForestryUniversity of British ColumbiaVancouverBC V6T 1Z4Canada

Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate ***,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management *** this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of *** capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were ***,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water *** removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water *** general,thinning may be an appropriate management measure to promote *** WUE to cope with seasonal droughts under future extreme climates.

关键词： Stable carbon isotope Water use efficiency Thinning Understory removal Photosynthetic capacity Needle water potential

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Interference alignment scheme for massive MIMO system

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 19-24页

作者： jiang jing LV Wei SUN Bo LU Guang-yue XIE Yong-bin School of Communication and Information Engineering Xi'an University of Posts & Telecommunications Wireless Technology Pre-research Unit ZTE Cooperation

The performance of massive multiple-input multiple-output （MIMO） system is limited by pilot contamination. To reduce the pilot contamination, uplink and downlink precoding algorithms are put forward based on interference alignment criterion. In the uplink receiving processing, the target function aligns the pilot contamination and the interference signals to the same null space and acquires the maximal space degree of the desired signals. The uplink receiving precoding matrix is solved on maximal signal to interference plus noise ratio （SINR） criterion considering the impact of the pilot contamination on channel estimations. The uplink receiving precoding matrix is used as the downlink transmitting precoding matrix. Exploiting the channel reciprocity, it is proved that, if the uplink receiving precoding matrix achieves maximal S1NR, the identical precoding matrix can be used in the downlink transmission and acquires maximal signal to leakage plus noise ratio （SLNR）. Simulations show that the spectrum efficiency of the proposed algorithm can reach about 1.5 times higher than that of popular matched filtering （MF） precoding algorithm, and about 1.1 times higher than multi-cell minimum mean square error （MMSE） precoding algorithm. The performance of the proposed algorithm can be improved approximately linearly with the increasing of the number of antennas.

关键词： massive MIMO large scale MIMO pilot contamination precoding interference alignment

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Functional characterization of(E)-β-caryophyllene synthase from lima bean and its up-regulation by spider mites and alamethicin

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Journal of Integrative Agriculture 2017年第10期16卷 2231-2238页

作者： LI Feng-qi FU Ning-ning ZHOU jing-jiang WANG Gui-rong Institute of Plant and Environment Protection Beijing Academy of Agriculture and Forestry Sciences Institute of Plant Protection Chinese Academy of Agricultural Sciences Department of Biological Chemistry and Crop Protect Rothamsted Research

（E）-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of （E）-β-caryophyllene synthase in lima bean （Phaseolus lunatus）. Here, we report a new full-length cDNA （PICAHS） encoding （E）-β-caryophyllene synthase, a possible key enzyme of plant defence. The cDNA of PICAHS contains an open reading frame of 1 761 bp, encoding a protein of 586 amino acids with a predicted mass of 67.95 kDa. The deduced amino acid sequence shows 52% identity with sesquiterpene synthase MtCAHS of Med- icago truncatula. Based on phylogenetic analysis, PICAHS is classified as the terpene synthases （TPS）-a subfamily. The recombinant enzyme, expressed in Escherichia coil, catalysed the formation of a major product （E）-β-caryophyllene （82%） and a minor product a-humulene （18%） from farnesyl dJphosphate. Real-time quantitative PCR （qRT-PCR） analysis found that the PICAHS transcript was significantly up-regulated in leaves after treatment with spider mites and alamethicin （ALA）, suggesting its ecological function in plant defence.

关键词： plant defence terpene synthases (E)--caryophyllene lima bean

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Molecular and functional characterization of a candidate sex pheromone receptor OR1 in Spodoptera fitura

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Insect Science 2017年第4期24卷 543-558页

作者： Qin-Hui Zhang Zhong-Nan Wu jing-jiang Zhou Yong-Jun Du College of Life Sciences Sichuan University Chengdu 610065 China Institute of Health & Environmental Ecology Wenzhou Medical University Wenzhou Zhejiang 325035 China Department of Biological Chemistry and Crop Protection Rothamsted Research BBSRC Harpenden Herts. AL5 2JQ UK

Olfaction is primarily mediated by highly specified olfactory receptors （ORs）. Here, we cloned and identified an olfactory receptor, named SlituOR1 （Genbank no. JN835269）, from Spodoptera litura and found evidence that it is a candidate pheromone receptor. It exhibited male-biased expression in the antennae, where it was localized at the base of sensilla trichoidea, the antennal sensilla mainly responsive to pheromones in moths. Conserved orthologues of this receptor, found among known pheromone receptors within the Lepidoptera, and SlituOR1 were placed among a clade of candidate pheromone re- ceptors in a phylogeny tree of insect OR gene sequences. SlituOR1 showed differential expression in S. litura populations attracted to traps baited with different ratios of the two sex pheromone components （9Z,11E）-tetradecadienyl acetate （Z9E11-14：OAc） and （9Z,12E）-tetradecadienyl acetate （Z9E12-14：OAc）. Knocking down of SlituOR1 by RNA interference reduced the electroantennogram （EAG） response to Z9E11-14：OAc, and this result is consistent with the field trapping experiment. We infer that variation in transcrip- tion levels of olfactory receptors may modulate sex pheromone perception in male moths and could provide some of the flexibility required to maintain the functionality of com- munication with females when a population is adapting to a new niche and reproductive isolation becomes an advantage.

关键词： electroantennogram (EAG) individual variation in situ hybridization ol-factory receptor (9Z, 11E)-tetradecadienyl acetate (9Z, 12E)-tetradecadienyl acetate RNAinterference

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Effects of deficit irrigation with saline water on spring wheat growth and yield in arid Northwest China

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Journal of Arid Land 2013年第2期5卷 143-154页

作者： jing jiang ZaiLin HUO ShaoYuan FENG ShaoZhong KANG FenXing WANG ChaoBo ZHANG College of Water Science and Engineering Taiyuan University of Technology Centre for Agricultural Water Research in China China Agricultural University College of Water Science and Engineering Yangzhou University

Field experiments were conducted in 2008 and 2009 to study the effects of deficit irrigation with saline water on spring wheat growth and yield in an arid region of Northwest China. Nine treatments included three salinity levels sl, s2 and s3 （0.65, 3.2, and 6.1 dS/m） in combination with three water levels wl, w2 and w3 （375, 300, and 225 mm）. In 2008, for most treatments, deficit irrigation showed adverse effects on wheat growth; meanwhile, the effect of saline irrigation was not apparent. In 2009, growth parameters of wl treatments were not always optimal under saline irrigation. At 3.2 and 6.1 dS/m in 2008, the highest yield was obtained by wl treatments, however, in 2009, the weight of 1,000 grains and wheat yield both followed the order w2 〉 wl 〉 w3. In this study, spring wheat was sensitive to water deficit, especially at the booting to grain-filling stages, but was not significantly affected by saline irrigation and the combination of the two factors. The results demonstrated that 300-mm irrigation water with a salinity of less than 3.2 dS/m is suitable for wheat fields in the study area.

关键词： saline water irrigation leaf area index (LAI) leaf potential yield components

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Geometric phase of an open double-quantum-dot system detected by a quantum point contact

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Chinese Physics B 2020年第3期29卷 75-81页

作者： Qian Du Kang Lan Yan-Hui Zhang Lu-jing jiang School of Physics and Electronics Shandong Normal UniversityJinan 250014China

We study theoretically the geometric phase of a double-quantum-dot(DQD) system measured by a quantum point contact(QPC) in the pure dephasing and dissipative environments, respectively. The results show that in these two environments, the coupling strength between the quantum dots has an enhanced impact on the geometric phase during a quasiperiod. This is due to the fact that the expansion of the width of the tunneling channel connecting the two quantum dots accelerates the oscillations of the electron between the quantum dots and makes the length of the evolution path *** addition, there is a notable near-zero region in the geometric phase because the stronger coupling between the system and the QPC freezes the electron in one quantum dot and the solid angle enclosed by the evolution path is approximately zero,which is associated with the quantum Zeno effect. For the pure dephasing environment, the geometric phase is suppressed as the dephasing rate increases which is caused only by the phase damping of the system. In the dissipative environment,the geometric phase is reduced with the increase of the relaxation rate which results from both the energy dissipation and phase damping of the system. Our results are helpful for using the geometric phase to construct the fault-tolerant quantum devices based on quantum dot systems in quantum information.

关键词： geometric phase decoherence quantum transport

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MALAT1 promotes platelet activity and thrombus formation through PI3k/Akt/GSK-3βsignalling pathway

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Stroke & Vascular Neurology 2023年第3期8卷 181-192,I0001-I0004页

作者： Yeying Sun Tao Wang Yan Lv Jiahua Li Xiaoli jiang jing jiang Daolai Zhang Weihua Bian Chunxiang Zhang College of Pharmacy Binzhou Medical UniversityYantaiShandongChina College of Life Sciences Yantai UniversityYantaiShandongChina Department of Cardiology Southwest Medical UniversityLuzhouSichuanChina

Background Ischaemic stroke and other cardiovascular illnesses are characterised by abnormalities in the processes of thrombosis and haemostasis,which rely on platelet *** platelets,a wide variety of microRNAs(long non-coding RNA,lncRNAs)is *** to the absence of nuclear DNA in platelets,lncRNAs may serve as critical post-transcriptional regulators of platelet ***,research into the roles of lncRNAs in platelets is *** The purpose of this study is to learn more about the molecular mechanism by which MALAT1 affects platelet activity and thrombus ***/results The CD34+megakaryocytes used in this research as an in vitro model for human megakaryocytes and *** adhesion and spreading are enhanced in the absence and presence of agonists in CD34+megakaryocytes subjected to MALAT1 knockdown(KD).The adhesion and activity of platelet-like particles produced by MALAT1 KD cells are significantly enhanced at rest and after thrombin *** development on a collagen matrix is also greatly enhanced in the microfluidic whole-blood perfusion model:platelets lacking MALAT1 exhibit elevated accumulation,distributing area and *** addition,MALAT1-deficient mice bleed less and form a stable occlusive thrombus more quickly than wild-type *** and PDK1 regulated the activity of MALAT1 in platelets to carry out its PI3k/Akt/GSK-3βsignalling pathway-related *** The suppression of MALAT1 expression significantly increases platelet adhesion,spreading,platelet activity,and thrombus *** may constitute a unique class of platelet function modulators.

关键词： MALAT1 thrombus platelet

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Strain-hardening and warm deformation behaviors of extruded Mg-Sn-Yb alloy sheet

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Journal of Magnesium and Alloys 2014年第2期2卷 116-123页

作者： jing jiang Guangli Bi Guoyong Wang Qing jiang Jianshe Lian Zhonghao jiang Key Laboratory of Automobile Materials College of Materials Science and EngineeringJilin UniversityNanling CampusChangchun 130025China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China

Strain-hardening and warm deformation behaviors of extruded Mg-2Sn-0.5Yb alloy(at.%)sheet were investigated in uniaxial tensile test at temperatures of 25-250 ℃ and strain rates of 1×10^(−3) s^(−1)-0.1 s^(−1).The data fit with the Kocks-Mecking type plots were used to show different stages of strain *** III-stage and IV-stage,the absence of the II-stage strain hardening at room temperature should be related to the sufficient dynamic recrystallization during *** decrease of strain hardening ability of the alloy after yielding was attributed to the reduction of dislocation density with increasing testing *** rate sensitivity(SRS)was significantly enhanced with increasing temperature,and the corresponding m-value was calculated as 0.07-0.12,which indicated that the deformation mechanism was dominated by the climb-controlled dislocation creep at 200 ℃.Furthermore,the grain boundary sliding(GBS)was activated at 250 ℃,which contributed to the higher *** activation energy was calculated as 213.67 kJ mol^(−1),which was higher than that of lattice diffusion or grain boundary *** addition,the alloy exhibited a quasi superplasticity at 250 ℃ with a strain rate of 1×10^(−3) s^(−1),which was mainly related to the fine microstructure and the presence of the Mg2Sn and Mg2(Sn,Yb)particles.

关键词： Mg-Sn-Yb alloy sheet Strain hardening Strain rate sensitivity Activation energy

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Preparation and surface modification of 3D printed Ti-6Al-4V porous implant

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Rare Metals 2021年第5期40卷 1164-1172页

作者： Chun-Yong Liang Xiao-jing jiang Rui-Long Ji Bao-E Li Xian-Rui Zou Hong-Shui Wang jing-Zu Hao Tai Yang School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Tianjin Key Laboratory of Laminating Fabrication and Interface Control Technology for Advanced Materials Hebei University of TechnologyTianjin 300130China

Three-dimensional(3D)printed titanium alloy implants hold enormous potential in orthopedic applications to avoid stress ***,titanium alloy is bioinert,limiting its application and making surface modification a *** this paper,porous implants were treated by acid etching and anodizing to improve the bioactivity,which was evaluated by simulated body fluid(SBF)immersion *** results showed that,after surface modification,micro-nanocomposite structures were obtained on the titanium surface,and after immersing in SBF for 2 weeks,the implants showed a drastically enhanced apatite forming ability,confirming improved ***,the surface structures were different at different positions and it is believed that this phenomenon is closely related to the different current densities of the surfaces during anodic *** research evaluates the effect of anodic oxidation at different voltages on the surface modification and provides a reference for improving the bioactivity of the medical porous implant surface prepared by 3 D printing.

关键词： Three-dimensional(3D)printing Porous implants Anodic oxidation Composite structure Current density

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Empirical Research in Software Engineering -- A Literature Survey

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Journal of Computer Science & Technology 2018年第5期33卷 876-899页

作者： Li Zhang Jia-Hao Tian jing jiang Yi-Jun Liu Meng-Yuan Pu Tao Yue State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China College of Software Beihang University Beijing 100191 China Simula Research Laboratory Martin Lingesvei 25 1364 Fornebu Norway

Empirical research is playing a significant role in software engineering （SE）, and it has been applied to evaluate software artifacts and technologies. There have been a great number of empirical research articles published recently. There is also a large research community in empirical software engineering （ESE）. In this paper, we identify both the overall landscape and detailed implementations of ESE, and investigate frequently applied empirical methods, targeted research purposes, used data sources, and applied data processing approaches and tools in ESE. The aim is to identify new trends and obtain interesting observations of empirical software engineering across different sub-fields of software engineering. We conduct a mapping study on 538 selected articles from January 2013 to November 2017, with four research questions. We observe that the trend of applying empirical methods in software engineering is continuously increasing and the most commonly applied methods are experiment, case study and survey. Moreover, open source projects are the most frequently used data sources. We also observe that most of researchers have paid attention to the validity and the possibility to replicate their studies. These observations are carefully analyzed and presented as carefully designed diagrams. We also reveal shortcomings and demanded knowledge/strategies in ESE and propose recommendations for researchers.

关键词： empirical software engineering empirical method systematic mapping study

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