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1Learning-based lensless imaging through optically thick scattering media显示文摘The problem of imaging through thick scattering media is encountered in many disciplines of science,ranging from mesoscopic physics to astronomy.Photons become diffusive after propagating through a scattering medium with an optical thickness of over 10 times the scattering mean free path.As a result,no image but only noise-like patterns can be directly formed.We propose a hybrid neural network for computational imaging through such thick scattering media,demonstrating the reconstruction of image information from various targets hidden behind a white polystyrene slab of 3 mm in thickness or 13.4 times the scattering mean free path.We also demonstrate that the target image can be retrieved with acceptable quality from a very small fraction of its scattered pattern,suggesting that the speckle pattern produced in this way is highly redundant.This leads to a profound question of how the information of the target being encoded into the speckle is to be addressed in future studies.Meng Lyu Hao Wang Guowei Li Shanshan Zheng Guohai Situ 2019Advanced Photonics2019,1,3:28
2Melatonin alleviates intervertebral disc degeneration by disrupting the IL-1β/NF-κB-NLRP3 inflammasome positive feedback loop显示文摘The inflammatory response is induced by the overexpression of inflammatory cytokines, mainly interleukin(IL)-1β, and is one of the main causes of intervertebral disc degeneration(IVDD). NLR pyrin domain containing 3(NLRP3) inflammasome activation is an important source of IL-1β. As an anti-inflammatory neuroendocrine hormone, melatonin plays various roles in different pathophysiological conditions. However, its roles in IVDD are still not well understood and require more examination. First, we demonstrated that melatonin delayed the progression of IVDD and relieved IVDD-related low back pain in a rat needle puncture IVDD model;moreover, NLRP3 inflammasome activation(NLRP3, p20, and IL-1β levels) was significantly upregulated in severely degenerated human discs and a rat IVDD model. Subsequently, an IL-1β/NF-κB-NLRP3 inflammasome activation positive feedback loop was found in nucleus pulposus(NP) cells that were treated with IL-1β. In these cells, expression of NLRP3 and p20 was significantly increased, NF-κB signaling was involved in this regulation, and mitochondrial reactive oxygen species(mt ROS)production increased. Furthermore, we found that melatonin disrupted the IL-1β/NF-κB-NLRP3 inflammasome activation positive feedback loop in vitro and in vivo. Melatonin treatment decreased NLRP3, p20, and IL-1β levels by inhibiting NF-κB signaling and downregulating mt ROS production. Finally, we showed that melatonin mediated the disruption of the positive feedback loop of IL-1β in vivo. In this study, we showed for the first time that IL-1β promotes its own expression by upregulating NLRP3 inflammasome activation. Furthermore, melatonin disrupts the IL-1β positive feedback loop and may be a potential therapeutic agent for IVDD.Fan Chen Guowei Jiang Hui Liu Zemin Li Yuxin Pei Hua Wang Hehai Pan Haowen Cui Jun Long Jianru Wang Zhaomin Zheng 2020Bone Research2020,8,2:18
3Geochemistry and spatial distribution of OIB and MORB in A’nyemaqen ophiolite zone: Evidence of Majixue-shan ancient ridge-centered hotspot显示文摘The mafic volcanic association is made up of OIB, E-MORB and N-MORB in the A'nyemaqen Paleozoic ophiolites. Compared with the same type rocks in the world, the mafic rocks generally display lower Nb/U and Ce/Pb ratios and some have Nb depletion and Pb enrichment. The OIB are LREE-enriched with (La/Yb)N =5―20, N-MORB are LREE-depleted with (La/Yb)N = 0.41―0.5. The OIB are featured by incompatible element enrichment and the N-MORB are obviously depleted with some metasomatic ef- fect, and E-MORB are geochemically intermediated. These rocks are distributed around the Majixue- shan OIB and gabbros in a thickness greater than a thousand meters and transitionally change along the ophiolite extension in a west-east direction, showing a symmetric distribution pattern as centered by the Majixueshan OIB, that is, from N-MORB, OIB and E-MORB association in the Dur'ngoi area to OIB in the Majixueshan area and then to N-MORB, OIB and E-MORB assemblage again in the Buqing- shan area. By consideration of the rock association, the rock spatial distribution and the thickness of the mafic rocks in the Majixueshan, coupled with the metasomatic relationship between the OIB and MORB sources, it can be argued that the Majixueshan probably corresponds to an ancient hotspot or an ocean island formed by mantle plume on the A'nyemaqeh ocean ridge, that is the ridge-centered hotspot, tectonically similar to the present-day Iceland hotspot.GUO AnLin ZHANG GuoWei SUN YanGui ZHENG JianKang LIU Ye WANG JianQi 2007Science China Earth Sciences2007,50,2:11
4Computational methods and engineering applications of static/dynamic aeroelasticity based on CFD/CSD coupling solution显示文摘The CFD/CSD coupling method is turning into the main research direction for the static/dynamic aeroelastic analyses.If one wants to use the method for the complex engineering aeroelastic problems,he needs to investigate the relative aeroelastic algorithms,such as the numerical computational method of unsteady aerodynamic forces,equivalent low-dimensional structural finite element model and the solution method of structural dynamic equations,data transfer technique between fluid and structure,the moving grid method,etc.Besides,he also needs to improve the computational efficiency by such as massive parallel CFD algorithm,reduced-order model(ROM) of unsteady aerodynamic forces,etc.In this paper,based on the authors' recent investigations,the research progresses in computational aeroelastic methods and their applications to engineering problem are summarized.YANG GuoWei ZHENG GuanNan LI GuiBo 2012Science China(Technological Sciences)2012,55,9:6
5A more consistent intraluminal rhesus monkey model of ischemic stroke显示文摘Endovascular surgery is advantageous in experimentally induced ischemic stroke because it causes fewer cranial traumatic lesions than invasive surgery and can closely mimic the pathophysiology in stroke patients. However, the outcomes are highly variable, which limits the accuracy of evaluations of ischemic stroke studies. In this study, eight healthy adult rhesus monkeys were randomized into two groups with four monkeys in each group: middle cerebral artery occlusion at origin segment(M1) and middle cerebral artery occlusion at M2 segment. The blood flow in the middle cerebral artery was blocked completely for 2 hours using the endovascular microcoil placement technique(1 mm × 10 cm)(undetachable), to establish a model of cerebral ischemia. The microcoil was withdrawn and the middle cerebral artery blood flow was restored. A reversible middle cerebral artery occlusion model was identified by hematoxylin-eosin staining, digital subtraction angiography, magnetic resonance angiography, magnetic resonance imaging, and neurological evaluation. The results showed that the middle cerebral artery occlusion model was successfully established in eight adult healthy rhesus monkeys, and ischemic lesions were apparent in the brain tissue of rhesus monkeys at 24 hours after occlusion. The rhesus monkeys had symptoms of neurological deficits. Compared with the M1 occlusion group, the M2 occlusion group had lower infarction volume and higher neurological scores. These experimental findings indicate that reversible middle cerebral artery occlusion can be produced with the endovascular microcoil technique in rhesus monkeys. The M2 occluded model had less infarction and less neurological impairment, which offers the potential for application in the field of brain injury research.Bo Zhao Guowei Shang Jian Chen Xiaokun Geng Xin Ye Guoxun Xu Ju Wang Jiasheng Zheng Hongjun Li Fauzia Akbary Shengli Li Jing Lu Feng Ling Xunming Ji 2014Neural Regeneration Research2014,9,23:6
6Petrogenesis and tectonic implications of Indosinian granitoids from Western Qinling Orogen,China:Products of magma-mixing and fractionation显示文摘The Western Qinling Orogen(WQO) is characterized by voluminous distribution of Indosinian granitoids,the formation of which provides an important window to unravel the geochemical and geodynamic evolution and associated metallogeny.Here we investigate a group of intrusions termed 'Five Golden Flowers' based on petrological,geochemical,zircon U-Pb geochronological and Lu-Hf isotopic studies on the granitoids and their mafic microgranular enclaves(MMEs).Our results show that these intrusions are genetically divided into two types,namely,magma-mixing and highly fractionated.The Jiaochangba,Lujing,Zhongchuan,and Luchuba granitoids are biotite monzogranites(220±0.8 Ma to 217±2.6 Ma) with abundant coeval MMEs(220±.1 Ma to 217±2.7 Ma).The rocks contain moderate to high SiO2,high MgO,Rb,Sr,Ba,and Th contents,but low TiO2,P2 O5,and Sc values,A/CNK of <1.1,and a range of εHf(t) values of-11.7 to +2.23 with corresponding TDM2values of 1967-1228 Ma.The MMEs possess K-feldspar megacrysts,abundant acicular apatites,and show lopsided textures.They have lower SiO2,Al2 O3,and Th contents,but higher MgO,TiO2,and Sc,with εHf(t) values of-18.0 to +3.18 and TDM1 of 849-720 Ma.The data indicate that the MMEs were derived from a magma sourced from the enriched lithospheric mantle.We suggest that these host granitoids were produced by partial melting of latePaleoproterozoic to early-Mesoproterozoic lower crust with the involvement of Neoproterozoic SCLM-derived mafic magmas.The Baijiazhuang pluton is dominantly composed of leucogranite(muscovite granite and twomica monzogranite,216±1.5 Ma) without MMEs.The rocks are peraluminous with high A/CNK(1.06-1.27).Compared with the other four granitoids,the Baijiazhuang leucogranite shows higher SiO2 content,markedly lower concentrations of TiO2,MgO,Al2 O3,CaO,and Fe2 O3T,and lower LREE/HREE and(La/Yb)N values.These leucogranites are also rich in Rb,Th,and U,and display marked depletions in Ba,Sr,Ti,and Eu,indicating that they experienced significant fractionation.Zircon εHf(t) values(-10.2 to-3.27) and TDM2(1868-1424 Ma),as well as the Nb/Ta and K2 O/Na2 O values are similar to the other four granitoids,indicating that they are likely to have been derived from a similar source;with sediments playing only a minor role in the magma generation.The low contents of Yb and Y suggest that their partial melting was controlled by garnets and micrographic texture of K-feldspar reflects high-temperature melting through undercooling.Based on the above features,we infer that the Baijiazhuang leucogranite likely represents the product of high degree fractionation of the I-type biotite monzogranite magma which generated the other four granitoids at relatively high temperatures,within magma chambers at mid-crust depths.We propose that the granitoid suite was formed in the transitional setting from synto post-collision during the collisional orogeny between the SCB and NCB,following break-off of the subducted South China Block lithosphere during 220-216 Ma.Xiao Xiong Laimin Zhu Guowei Zhang M.Santosh Hang Jiang Jun Zheng Anlin Guo Lele Ding 2020Geoscience Frontiers2020,11,4:6
7SARS-CoV-2 promotes RIPK1 activation to facilitate viral propagation显示文摘Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is the ongoing global pandemic that poses substantial challenges to public health worldwide.A subset of COVID-19 patients experience systemic inflammatory response,known as cytokine storm,which may lead to death.Receptor-interacting serine/threonine-protein kinase 1(RIPK1)is an important mediator of inflammation and cell death.Here,we examined the interaction of RIPK1-mediated innate immunity with SARS-CoV-2 infection.We found evidence of RIPK1 activation in human COVID-19 lung pathological samples,and cultured human lung organoids and ACE2 transgenic mice infected by SARS-CoV-2.Inhibition of RIPK1 using multiple smallmolecule inhibitors reduced the viral load of SARS-CoV-2 in human lung organoids.Furthermore,therapeutic dosing of the RIPK1 inhibitor Nec-1s reduced mortality and lung viral load,and blocked the CNS manifestation of SARS-CoV-2 in ACE2 transgenic mice.Mechanistically,we found that the RNA-dependent RNA polymerase of SARS-CoV-2,NSP12,a highly conserved central component of coronaviral replication and transcription machinery,promoted the activation of RIPK1.Furthermore,NSP12323L variant,encoded by the SARS-CoV-2 C14408T variant first detected in Lombardy,Italy,that carries a Pro323Leu amino acid substitution in NSP12,showed increased ability to activate RIPK1.Inhibition of RIPK1 downregulated the transcriptional induction of proinflammatory cytokines and host factors including ACE2 and EGFR that promote viral entry into cells.Our results suggest that SARS-CoV-2 may have an unexpected and unusual ability to hijack the RIPK1-mediated host defense response to promote its own propagation and that inhibition of RIPK1 may provide a therapeutic option for the treatment of COVID-19.Gang Xu Ying Li Shengyuan Zhang Haoran Peng Yunyun Wang Dekang Li Taijie Jin Zhuohao He Yilun Tong Chunting Qi Guowei Wu Kangyun Dong Jizhou Gou Yang Liu Tongyang Xiao Jing Qu Liang Li Liang Liu Ping Zhao Zheng Zhang Junying Yuan 2021Cell Research2021,31,12:6
8Flutter analyses of complete aircraft based on hybrid grids and parallel computing显示文摘A tightly coupled method was developed to analyse aeroelasticity by constructing subiterative schemes for fluid and structural equations of motion,respectively.With MPI partition parallel computing,the fluid was solved by Navier-Stokes equations based on hybrid grids.A new unstructured background grid deformtion method was used for the CFD grid deformation.The transonic flutter wind tunnel model of a complete aircraft was simulated to validate the developed method.The flutter characteristics of the aircraft was analysed and compared with the test results.It indicates that the devoloped method has a relatively higher precision and can be used for aeronautical engineering application.ZHENG GuanNan YANG GuoWei QIAN Wei 2013Science China(Technological Sciences)2013,56,2:6
9Zircon U-Pb Geochronology and Geochemical Characteristics of the Volcanic Host Rocks from the Tongyu VHMS Copper Deposit in the Western North Qinling Orogen and Their Geological Significance显示文摘Precise in situ zircon U-Pb dating and Lu–Hf isotopic measurement using an LA-ICP-MS system, whole-rock major and trace element geochemistry and Sr–Nd isotope geochemistry were conducted on the volcanic host rocks of the Tongyu copper deposit on the basis of further understanding of its geological characteristics. Three zircon samples from the volcanic host rocks yielded 206Pb/238 U weighted average ages ranging from 436±4 Ma to 440±5 Ma, which are statistically indistinguishable and coeval with the ca. 440 Ma northward subduction event of the Paleo-Qinling oceanic slab. The volcanic host rocks were products of magmatic differentiation that evolved from basalt to andesite to dacite to rhyolite, forming an integrated tholeiitic island arc volcanic rock suite. The primitive mantle-normalized trace element patterns for most samples show characteristics of island arc volcanic rocks, such as relative enrichment of LILE(e.g. Th, U, Pb and La) and depletion of HFSE(e.g. Nb, Ta, Ti, Zr and Hf). Discrimination diagrams of Ta/Yb vs Th/Yb, Ta vs Th, Yb vs Th/Ta, Ta/Hf vs Th/Hf, Hf/3 vs Th vs Nb/16, La vs La/Nb and Nb vs Nb/Th all suggest that both the volcanic host rocks from the Tongyu copper deposit and the volcanic rocks from the regional Xieyuguan Group were formed in an island arc environment related to subduction of an oceanic slab. Values of ISr(0.703457 to 0.708218) and εNd(t)(-2 to 5.8) indicate that the source materials of volcanic rocks from the Tongyu copper deposit and the Xieyuguan Group originated from the metasomatised mantle wedge with possible crustal material assimilation. Most of the volcanic rock samples show good agreement with the values of typical island arc volcanic rocks in the ISr-εNd(t) diagram. The involvement of crustal-derived material in the magma of the volcanic rocks from the Tongyu copper deposit was also reflected in the zircon εHf(t) values, which range from-3.08 to 10.7, and the existence of inherited ancient xenocrystic zircon cores(2616±39 Ma and 1297±22 Ma). The mineralization of the Tongyu copper deposit shows syn-volcanic characteristics such as layered orebodies interbedded with the volcanic rock strata, thus, the zircon U-Pb age of the volcanic host rocks can approximately represent the mineralization age of the Tongyu copper deposit. Both the Meigou pluton and the volcanic host rocks were formed during the ca. 440 Ma northward subduction of the Paleo-Qinling Ocean when high oxygen fugacity aqueous hydrothermal fluid released by dehydration of the slab and the overlying sediments fluxed into the mantle wedge, triggered partial melting of the mantle wedge, and activated and extracted Cu and other ore-forming elements. The magma and ore-bearing fluid upwelled and erupted, and consequently formed the island arc volcanic rock suite and the Tongyu VHMS-type copper deposit.XIONG Xiao ZHU Laimin LI Ben ZHANG Guowei GONG Hujun ZHENG Jun JIANG Hang 2015Acta Geologica Sinica(English Edition)2015,89,6:5
10Alkali-activation reactivity of chemosynthetic Al_2O_3-2SiO_2 powders and their ^(27)Al and ^(29)Si magic-angle spinning nuclear magnetic resonance spectra显示文摘Pure Al_2O_3-2SiO_2 powders were prepared by sol-gel and coprecipitation methods,and their alkaliactivation reactivities were compared.The alkali-activation reactivity of the powder prepared by the sol-gel method was higher than that of the powder prepared by the coprecipitation method.The powders were investigated by ^(27)AI and ^(29)Si magic-angle spinning nuclear magnetic resonance spectroscopy(MAS NMR) to understand the relationship between their structure and alkali-activation reactivity.The ^(27)Al MAS NMR data showed that the five-coordinate AI content of the powder prepared by the sol-gel method was higher than that of the powder prepared by coprecipitation.The higher content of five-coordinate Al corresponded to higher alkali-activation reactivity.The ^(29)Si MAS NMR data showed that for the powder prepared by the sol-gel method,silicon was replaced by aluminum at secondary coordination sites of the central Si atoms during calcination.However,for the powder prepared by single-batch coprecipitation,the main change was from a low degree of polycondensation to a high degree of polycondensation.Guangjian Zheng Xuemin Cui Dong Huang Jinying Pang Guowei Mo Shujuan Yu Zhangfa Tong 2015Particuology2015,13,5:3
11Clinical observations on the treatment of infantile hemangiomas with topical imiquimod 5% cream显示文摘Objective:To observe the efficacy and safety of topical imiquimod 5% cream in the treatment of uncomplicated infantile hemangiomas (IHs). Methods:A total of 68 IHs were treated with topical imiquimod 5% cream. Among them,36 were superficial,22 were mixed,and 10 were deep. The size of IHs ranged from 1.0 cm × 1.5 cm to an area of a whole forearm. All the hemangiomas were in a proliferative stage. Imiquimod was applied 3 times weekly in 44 patients and 5 times weekly in 24 patients for up to 36 weeks. Results:All superficial IHs improved,and 18 achieved complete clinical resolution,10 had excellent improvement,5 showed moderate improvements,and 3 patients displayed minimal improvement. Two mixed IHs showed excellent improvement,3 showed moderate improvement and 5 mani-fested minimal improvements. The remaining 12 mixed IHs and all deep IHs did not respond to the therapy. The total incidence of local adverse events was 58.82%(40/68),which included erythema or edema,local itching,incrustation or peeling,erosion or ulceration,although most of these were mild to moderate reactions and did not affect the treatment. Scarring occurred in 2 mixed IHs. No systemic side effects developed. Conclusion:Imiquimod 5% cream may be a safe and effective alternative for the treatment of superficial IHs and some mixed IHs in which the superficial component predominates. An appropriate treatment duration for proliferative IHs treated with this therapy may be 24 weeks. Some local adverse events,such as crusting and erosion with possible scarring potential may occur and should be addressed by prompt,but temporary,discontinuation of the imiquimod. Topical imiquimod 5% cream can be prudently used in the treatment of IHs larger than 5.0 cm×5.0 cm in newborns and infants less than 6 months of age. To our knowledge,this is the largest IH group treated with imiquimod that has been reported in the literature to date.Zhengtuan Guo Guowei Li Quan Xu Ya Gaox Peng Li Xiansheng Zhang Yitao Duan Xinkui Guo Baijun Zheng 2009Journal of Nanjing Medical University2009,23,3:3
12Pitting corrosion behavior of cerium treated HSLA steel induced by sulfide inclusions in 3.5 wt% NaCl solution显示文摘Pitting corrosion behavior of Ce treated HSLA steels induced by sulfide inclusions in 3.5 wt% NaCl solution was investigated with potentiodynamic polarization and immersion corrosion test.The results show that Ce added steels exhibit better pitting corrosion resistance with lower corrosion current density and bigger pitting potential compared with steel without Ce,which is mainly attributed to optimized characteristics of spherical Ce-oxysulfide inclusions with less number density,smaller average size and lower pitting corrosion susceptibility.The spherical Ce_(2)O_(2) S inclusions precipitated on the surface of CeAlO_(3) inclusions in the Ce added steels induce pits with bigger opening mouth and shallow depth,reducing their tendency of extension to go deeper due to occlusion corrosion battery in the pitting holes.Furthermore,corrosion inhibitor Ce(OH)_(3) generated by Ce_(2)O_(2) S hydration can weaken electrochemical corrosion of the matrix micro-region around the pits.To avoid harmful bigger inclusions,Ce content in steels should be regulated within reasonable range,0.015 wt% Ce in present steels effectively modified inclusions to acquire the best pitting corrosion resistance of the steels.Wan Zheng Xueqiang Yan Shan Xiong Guowei Wang Guangqiang Li 2021Journal of Rare Earths2021,39,3:3
13Fabrication of flower-like mesoporous TiO_2 hierarchical spheres with ordered stratified structure as an anode for lithium-ion batteries显示文摘In this study, flower-like mesoporous TiO_2 hierarchical spheres(FMTHSs) with ordered stratified structure and TiO_2 nanoparticles(TNPs) were synthesized via a facile solvothermal route and an etching reaction. Multilamellar vesicles(MTSVs) and unilamellar TiO_2/SiO_2 vesicles(UTSVs) were prepared using cetyltrimethylammonium bromide and didodecyldimethylammonium bromide as structure-directing agents under different solvothermal conditions. FMTHSs and TNPs were obtained from the etching reactions of MTSVs and UTSVs, respectively, in an alkaline system. FMTHSs display flower-like, ordered stratified structures on each petal. The thickness of the ordered stratified structure is approximately3–6 nm, and the number of layers is approximately 2–4. The FMTHSs2 electrode exhibits the first discharge capacity of 212.4 m A h g^(-1) at 0.2 C, which is higher than that of TNPs electrode(167.6 mA h g^(-1)).The discharge specific capacity of FMTHSs2 electrode after 200 cycles at 1 C is 105.9 mA h g^(-1), which is higher than that of TNPs electrode(52.2 mA h g^(-1)) after the same number of cycles. The outstanding performance of FMTHSs2 electrode is attributed to the advantages of FMTHSs. In particular, their own stratified structure can provide additional active sites for reactions. The hierarchical structure can provide short diffusion length for Li^+, large electrolyte–electrode contact area, and superior accommodation of the strain of Li+intercalation/deintercalation.Yujie Zheng Bingjie Liu Pei Cao Hui Huang Jing Zhang Guowei Zhou 2019Journal of Materials Science & Technology2019,35,4:2
14Terpenes from Eupatorium adenophorum and their allelopathic effects on Arabidopsis seeds germination显示文摘Xu Zhao Zheng Guowei Niu Xuemei 2009Journal of Agricultural and Food Chemistry2009,57,2:1
15The increasing predominance of extreme precipitation in Southwest China since the late 1970s显示文摘本文分析了中国西南20世纪70年代末以来极端降水事件的频率,强度及其对总降水的贡献.结果表明,该地区约60%的降水站点极端降水的频率和强度正在增加,而大多数站点总降水频率明显减少.同时极端降水总量对总降水量的贡献有显著增加的趋势,极端降水在日益干旱的中国西南地区变得更具主导性.研究结果提醒应更加重视极端降水及其可能引发的次生灾害,如洪水,山体滑坡等.Guowei Zheng Yang Li Quanliang Chen Xin Zhou Guolu Gao Minggang Li Ting Duan 2022Atmospheric and Oceanic Science Letters2022,15,5:1
16Analysis of changes in the Panax notoginseng glycerolipidome in response to long-term chilling and heat显示文摘Long-term moderately high or low temperatures can damage economically important plants.In the present study,we treated Panax notoginseng,an important traditional Chinese medicine,with temperatures of 10,20,and 30℃for 30 days.We then investigated P.notoginseng glycerolipidome responses to these moderate temperature stresses using an ESI/MS-MS-based lipidomic approach.Both long-term chilling(LTC,10℃)and long-term heat(LTH,30℃)decreased photo pigment levels and photosynthetic rate.LTH-induced degradation of photo pigments and glycerolipids may further cause the decline of photosynthesis and thereafter the senescence of leaves.LTC-induced photosynthesis decline is attributed to the degradation of photo synthetic pigments rather than the degradation of chloroplastidic lipids.P.notoginseng has an especially high level of lysophosphatidylglycerol,which may indicate that either P.notoginseng phospholipase A acts in a special manner on phosphatidylglycerol(PG),or that phospholipase B acts.The ratio of sulfoquinovosyldiacylglycerol(SQDG)to PG increased significantly after LTC treatment,which may indicate that SQDG partially substitutes for PG.After LTC treatment,the increase in the degree of unsaturation of plastidic lipids was less than that of extraplastidic lipids,and the increase in the unsaturation of PG was the largest among the ten lipid classes tested.These results indicate that increasing the level of unsaturated PG may play a special role in maintaining the function and stability of P.notoginseng photosystems after LTC treatment.Tao Liu Jia Chen Furong Xu Xiahong He Shengchao Yang Youyong Zhu Weiqi Li Guowei Zheng 2020Plant Diversity2020,42,2:1
17Sirt1 deacetylates c-Myc and promotes c-Myc/Max association显示文摘Beibei Mao Guowei Zhao Xiang Lv Hou-Zao Chen Zheng Xue Ben Yang De-Pei Liu Chih-Chuan Liang 2011International Journal of Biochemistry and Cell Biology2011,,11:1
18Impacts of CO2 elevation on the physiology and seed quality of soybean显示文摘Understanding the responses of crops to elevated atmospheric carbon dioxide concentrations(E[CO2])is very important in terms of global food supplies.The present study investigates the effects of CO2 enrichment(to 800μmol mol^-1)on the physiology of soybean plants and the nutritional value of their seeds under growth chamber conditions.The photosynthesis of soybean was significantly promoted by E[CO2]at all growth stages,but leaf area and specific leaf weight were not affected.The levels of mineral elements in the leaves decreased under EICO2J.The soil properties after soybean cultivation under E[CO2]were not affected,except for a decrease in available potassium.Moreover,the levels of soluble sugars in the seeds were not affected by E[CO2].but the levels of natural antioxidants decreased.In addition,the level of oleic acid decreased under E[CO2].However,levels of fatty acid peroxidation and saturation were maintained.In conclusion.E[CO2] appears to have positive effects on the growth of cultivated soybean plants,but its influence on the nutritional values of soybean seeds is complex.Copyright?2019 Kunming Institute of Botany.Chinese Academy of Sciences.Guowei Zheng Jia Chen Weiqi Li 2020Plant Diversity2020,42,1:1
19Rate-Dependent Weakening of the Shear Force for the Submerged Granular Medium Based on the Experimental Study显示文摘An experimental study is conducted to describe rate-dependent shear strength in a submerged granular medium to understand the mystery of submarine landslides with extremely small slide angles and long run-out distances.The experimental apparatus allows a long-span shear strain rate,■,for five orders of magnitude from 10^(-4)to 10^(1)s^(-1).It is observed that(a)submerged sand under higher shear tend to have bigger yield strength;this positive response of rate effect is significantly affected by the magnitudes of shear strain rates.(b)the residual strength of soil is clearly affected negatively by shear strain rate,decreasing as shear strain rate increases;even small variations under lower rate cause notable differences in residual strength,indicating a novel weaking rate-dependent.The yield strength and residual strength are corresponding to the shear state of soil.Hence,it is enough experimentally to explain that as long as the submarine mass flow speeds up,the slope sliding can be kept by only a small amount of force along the slide direction,which can be calculated as the gravity component even with a small slide angle.Hu Zheng Guowei Dai Wuwei Mao Yu Huang 2023Journal of Earth Science2023,34,2:0
20Morphological characteristics of tree crowns of Cunninghamia lanceolata var. Luotian显示文摘The structural characteristics of the tree crowns of Cunninghamia lanceolata var. Luotian(herein, Luotian), a natural variety of C. lanceolata(Chinese-fir, herein Lanceolata) in China, were analyzed using trunk and branch measurements and biomass determinations. Samples from two typical cultivated varietal populations were collected, including twenty-six 15–23-year-old trees of Luotian from a plantation, and nine 16–23-year-old trees of Lanceolata. Our results show that Luotian and Lanceolata samples differed significantly in crown structure, morphological indices, and biomass:(1) the oldest live branches on Luotian trees were 5–6 years old and 8–11 years old on Lanceolata. The ages of the live branches were not affected by the ages of the Luotian trees, while live branch ages increased with ages of Lanceolata trees;(2) the maximumbranching order of Luotian was level two. Compared to Lanceolata, the average number of first-order lateral branches(i.e., branches emerging from the trunk) and the number of first-order lateral branch whorls per sample tree were 12.9% and 32.2% lower, respectively, in Luotian.However, the average number of branches within a single whorl was 21.8% greater in Luotian;the average number of branch whorls at crown height was 51.1% greater. Thus,the Luotian variety has thicker branches;(3) the average lateral branch angles in Luotian and Lanceolata sample trees were 105.2° and 61.4°, respectively. The branch angles in 53.0% of lateral branches on Luotian ranged from105° to 135°, but 30° to 90° in 96% of the lateral branches on Lanceolata. Within the same crown layer, the average branch angle was 1.6–2.2 times greater in Luotian, and the angle was directly proportional to crown thickness;(4) the average base diameter and branch length on Luotian were1.3 cm and 75.8 cm, respectively, and 1.6 cm and112.2 cm for Lanceolata. For individual trees, branch growth differed significantly(p < 0.01) between Luotian and Lanceolata. However, the lateral branches grew at a similar rate among Luotian trees of different ages;(5) the average height to the lowest live branch on Luotian was128.3% greater than on Lanceolata, resulting in a significant difference(p < 0.01) in crown size. Compared to the crowns on Lanceolata, the Luotian crowns were 45.3%higher and 41.1% wider, and the surface area, volume, and growth of the crown were 27.0%, 11.4%, and 2.4 times greater than for Lanceolata, respectively;and,(6) the biomass of Luotian and Lanceolata sample trees also differed significantly. The mean crown, branch, and leaf biomass for Luotian was 40.0%, 25.2%, and 54.1% of those for Lanceolata, respectively. However, the leaf biomass in each layer of the Luotian crown was higher thanthat of Lanceolata, and leaf biomass increased with crown thickness.Yezhou Xu Chaoqun Du Guowei Huang Zhenfang Li Xiangyang Xu Jingjin Zheng Chu Wu 2020Journal of Forestry Research2020,31,3:0
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