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A new mechanism of invader success: Exotic plant inhibits natural vegetation restoration by changing soil microbe com-munity 被引量:42
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作者 YUXingjun yudan +1 位作者 LUZhijun MAKeping 《Chinese Science Bulletin》 SCIE EI CAS 2005年第11期1105-1112,共8页
Since the 1950s of the last century, the exotic plant, Eupatorium adenophorum, has spread rapidly across southwest China, damaging native ecosystems and causing great economic losses. We examined the pH, N, P, K, and ... Since the 1950s of the last century, the exotic plant, Eupatorium adenophorum, has spread rapidly across southwest China, damaging native ecosystems and causing great economic losses. We examined the pH, N, P, K, and organic matter concentrations, and the bacterial community character (by Biolog EcoPlateTM) in soils from sites heavily and lightly invaded by this exotic species. Also, soil from the lightly invaded site was treated with a water extract of E. adenophorum roots to examine the effect of the plant on soil properties. We grew three plant species, one native and two exotic, in pot experiment using soil from heavily invaded site to examine the effects of the soil on these plants growth. The soil analysis demonstrated that the pH, organic matter, total N, total P and total K in soils from the heavily invaded site were only slightly different from those of the lightly invaded site, but concentrations of NH4+, NO?3 and available P and K in the heavily invaded site were greater than those in the lightly invaded site. The catabolic activity of soil bacterial community in the heavily invaded site was different from that in the lightly invaded site. The catabolic activity of bac- terial community in soils treated by the water extract of E. adenophorum roots changed and became similar to that in soils from the heavily invaded site. The pot experiment showed that the exotic plants growth in heavily invaded soil were not different from in lightly invaded soil; however, the native plant biomass decreased dramatically when grown in soil from the heavily invaded site as compared to soil from the lightly invaded site; and the same phenomenon was found when any potential allelopathic effects by E. adeno- phorum were eliminated by added activated carbon to those soils. Difference in soil nutrient availability and allelopathy could not explain this phenomenon of the native plant in the soils from the heavily and lightly invaded sites. Changes ob- served in the soil bacterial community were obviously related to native plan 展开更多
关键词 外来植物 泽兰属植物 土壤营养 微生物菌落 培植方式
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Endogenous neurogenesis in adult mammals after spinal cord injury 被引量:14
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作者 Hongmei Duan Wei Song +3 位作者 Wen Zhao yudan Gao Zhaoyang Yang Xiaoguang Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第12期1313-1318,共6页
During the whole life cycle of mammals, new neurons are constantly regenerated in the subgranular zone of the dentate gyms and in the subventricular zone of the lateral ventricles. Thanks to emerging methodologies, gr... During the whole life cycle of mammals, new neurons are constantly regenerated in the subgranular zone of the dentate gyms and in the subventricular zone of the lateral ventricles. Thanks to emerging methodologies, great progress has been made in the characterization of spinal cord endogenous neural stem cells (ependymal cells) and identification of their role in adult spinal cord development. As recently evidenced, both the intrinsic and extrinsic molecular mechanisms of ependymal cells control the sequential steps of the adult spinal cord neurogenesis. This review introduces the concept of adult endogenous neurogenesis, the reaction of ependymal cells after adult spinal cord injury (SCI), the heterogeneity and markers of ependymal cells, the factors that regulate ependymal cells, and the niches that impact the activation or differentiation of ependymal ceils. 展开更多
关键词 adult endogenous neurogenesis neural stem cells ependymal cells spinal cord injury adult mammals REGENERATION
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Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke 被引量:3
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作者 Hongmei Duan Shulun Li +11 位作者 Peng Hao Fei Hao Wen Zhao yudan Gao Hui Qiao Yiming Gu Yang Lv Xinjie Bao Kin Chiu Kwok-Fai So Zhaoyang Yang Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期409-415,共7页
Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactiv... Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown.In this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats.The gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery.This study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke. 展开更多
关键词 adult endogenous neurogenesis ANGIOGENESIS basic fibroblast growth factor-chitosan gel CHITOSAN functional recovery ischemic stroke neural stem cell newborn neuron
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Mesomechanism of steel fiber reinforcement and toughening of reactive powder concrete 被引量:9
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作者 JU Yang JIA yudan LIU HongBin CHEN Jian 《Science China(Technological Sciences)》 SCIE EI CAS 2007年第6期815-832,共18页
Reactive powder concrete (RPC) is a novel cement-based composite material with ultra-high strength. Embedding a certain amount of short steel fibers in the matrix can improve the RPC’s toughness and overcome the disa... Reactive powder concrete (RPC) is a novel cement-based composite material with ultra-high strength. Embedding a certain amount of short steel fibers in the matrix can improve the RPC’s toughness and overcome the disadvantage of high brittle- ness. In this paper, a number of direct uniaxial tension tests have been carried out with ‘8-shape’ RPC200 specimens. The bond-slip process, mesoscopic structural variation and mechanical characteristics of a fiber pullout of the matrix have been investigated using the real-time SEM loading system and CCD observation tech- niques. The influence of the volume of embedded short steel fibers in matrix on the mesoscopic morphology of attachments on the surface of a pulled individual fiber, the initial cracking force, the ultimate pullout force, interfacial bond strength and the pullout rupture energy have been analyzed. A general formulation relating these quantities to the volume of fibers in matrix has been proposed. The components comprising the interfacial bond strength have been outlined. In addition, the con- tribution that fibers make to enhance and toughen the reactive powder concrete has been discussed. It is shown that there exists an optimal threshold of fiber volume ρv, opt =1.5% at which the bond performance of a fiber pullout of RPC be- haves best. 展开更多
关键词 reactive powder concrete steel fiber INTERFACIAL BOND strength reinforcement and toughening mesomechanism
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A novel scheme for ultrashort terahertz pulse generation over a gapless wide spectral range:Raman-resonance-enhanced four-wave mixing 被引量:3
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作者 Jiaming Le yudan Su +2 位作者 Chuanshan Tian A.H.Kung Y.Ron Shen 《Light(Science & Applications)》 SCIE EI CAS CSCD 2023年第2期232-238,共7页
Ultrashort energetic terahertz(THz)pulses have created an exciting new area of research on light interactions with matter.For material studies in small laboratories,widely tunable femtosecond THz pulses with peak fiel... Ultrashort energetic terahertz(THz)pulses have created an exciting new area of research on light interactions with matter.For material studies in small laboratories,widely tunable femtosecond THz pulses with peak field strength close to MV cm-1 are desired.Currently,they can be largely acquired by optical rectification and difference frequency generation in crystals without inversion symmetry.We describe in this paper a novel scheme of THz pulse generation with no frequency tuning gap based on Raman-resonance-enhanced four-wave mixing in centrosymmetric media,particularly diamond.We show that we could generate highly stable,few-cycle pulses with near-Gaussian spatial and temporal profiles and carrier frequency tunable from 5 to>2o THz.They had a stable and controllable carrier-envelop phase and carried~15 nJ energy per pulse at 10 THz(with a peak field strength of~1 MV cm^(-1)at focus)from a O.5-mm-thick diamond.The measured THz pulse characteristics agreed well with theoretical predictions.Other merits of the scheme are discussed,including the possibility of improving the THz output energy to a much higher level. 展开更多
关键词 pulse ULTRASHORT tuning
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Toughness and characterization of reactive powder concrete with ultra-high strength 被引量:7
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作者 Yang Ju HongBin Liu +2 位作者 Jian Chen yudan Jia PeiHuo Peng 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第4期1000-1018,共19页
A number of three-point bending and fracture tests of 200 MPa-level reactive powder concrete (RPC) with the various fiber contents have been conducted to probe the nature and characteristics of toughness of RPC200. Th... A number of three-point bending and fracture tests of 200 MPa-level reactive powder concrete (RPC) with the various fiber contents have been conducted to probe the nature and characteristics of toughness of RPC200. The contribution of the embedded fibers to improving the crack-resistant capacity, energy absorption capacity and toughness with various deformation mechanisms has been analyzed. Taking account of that the first-crack deformation, peak-load deformation and their improvement varied with the fiber contents and that the deformation mechanism affected differently the performance at the first crack and the peak load, we took the peak-load deformation of plain RPC200 as the reference deformation to measure the toughness of fibered RPC200. Two toughness indices T <SUB>2(n&#8722;1)</SUB>(n) and FT <SUB>2(n&#8722;1)</SUB>(n) have been formulated based on P-&#948; responses and P-CMOD responses. The indices quantify the toughness of RPC200 with the various deformation mechanisms relative to perfectly elastoplastic materials by setting the toughness level 2(n&#8722;1) as the initial reference. It is shown that the toughness index T <SUB>2(n&#8722;1)</SUB>(n) reflects the function of fibers to improve the toughness of RPC with the deformation throughout specimens, but overestimates the contribution to enhancing the toughness in post-peak periods. It underestimates, on other hands, the contribution to improving the toughness in the period from the first crack to the peak load. In contrast, the toughness index FT <SUB>2(n&#8722;1)</SUB>(n) properly presents the capability that fibers absorb energy and constrain crack propagation in the matrix when the deformation is concentrated on the open crack. The proposed index unveils the contribution of fibers to toughening RPC200 both in the period from the first-crack to the peak load and in the period of post peak. This characterization method not only reveals the nature of toughness but also levels the toughness of RPC200. It could provide a way to establish an objective 展开更多
关键词 REACTIVE POWDER concrete TOUGHNESS CHARACTERIZATION index DEFORMATION mechanism flexure FRACTURE
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Protection of Omicron Sub-Lineage Infection Against Reinfection with Another Omicron Sub-Lineage:Systematic Review,Meta-Analysis,and Meta-Regression-Worldwide,2022-2023
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作者 Xu Guo Zuyao Cheng +5 位作者 Junhong Li yudan Song Hui Zheng Yamin Wang Chao Ma Zijian Feng 《China CDC weekly》 SCIE CSCD 2024年第26期624-628,I0001-I0009,共14页
Summary What is already known about this topic?Both the decline in immunity over time and the evolution of the virus play a role in the level of protection offered by a prior infection.What is added by this report?Poi... Summary What is already known about this topic?Both the decline in immunity over time and the evolution of the virus play a role in the level of protection offered by a prior infection.What is added by this report?Point estimates indicated variations in protection levels based on the initial infecting variant and the reinfecting variant.There was a consistent correlation between real-world protection,antigenic distance,and humoral immunity levels.Specifically,shorter antigenic distances and higher humoral immunity levels corresponded to enhanced real-world protection.What are the implications for public health practice?Our findings suggest that virological and immunological studies could help identify and assess the epidemic risk posed by new variants before they become dominant.Prompt incorporation of the latest variants into the antigen components of the coronavirus disease 2019(COVID-19)vaccines can significantly contribute to effective epidemic prevention and control measures. 展开更多
关键词 IMMUNITY prevention shorter
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Regulating atomic Fe-Rh site distance for efficient oxygen reduction reaction
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作者 Tong Liu yudan Chen +9 位作者 Airong Xu Xiaokang Liu Dong Liu Sicheng Li Hui Huang Li Xu Shuaiwei Jiang Qiquan Luo Tao Ding Tao Yao 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第4期1352-1359,共8页
Exploring the atomic interaction mechanisms of dense single-atom catalysts(SACs)is of great significance for their application in oxygen reduction reaction(ORR).However,the intrinsic mechanism of the site-distance eff... Exploring the atomic interaction mechanisms of dense single-atom catalysts(SACs)is of great significance for their application in oxygen reduction reaction(ORR).However,the intrinsic mechanism of the site-distance effect on the catalytic performance has been largely ignored.Here,we demonstrate the site-distance effect of Fe-Rh_(x)@NC catalysts in ORR theoretically and experimentally.Bader charge analysis reveals that the strong interaction between Fe and Rh atoms at a certain atomic distance(dFe-Rh)alters the catalytic electronic structure,facilitating the optimization of catalyst adsorption strength.Motivated by the theoretical calculations,we designed and synthesized the Fe-Rhx@NC catalysts through a spatial confinement strategy.The characterization results prove that the Fe-Rh_(2)@NC has the optimal d_(Fe-Rh),which improves its intrinsic ORR activity,providing a half wave potential of 0.91 V,higher than that of the commercial Pt/C(0.86 V).This study emphasizes the importance of determining the basic mechanism of the site-distance effect in dissimilar metal atoms catalysts,which is conducive to the design of efficient catalyst systems for practical applications. 展开更多
关键词 Density functional theory single-atom catalyst in-situ encapsulating site-distance effect oxygen reduction reaction
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An Outbreak of Serogroup Y Meningococcal Meningitis in a Private Secondary Vocational School-Guangzhou City,Guangdong Province,China,2023
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作者 Xiang Zeng Qing He +9 位作者 Yilan Li Yong Zhou Xiaoping Shao Pei Hu Jian Liang yudan Song Chao Ma Lijie Zhang Limei Sun Lei Luo 《China CDC weekly》 SCIE CSCD 2024年第12期242-246,I0005,共6页
What is already known about this topic?The inclusion of meningococcal vaccines in the National Immunization Program(NIP)over several years has significantly reduced the incidence of meningococcal meningitis in China t... What is already known about this topic?The inclusion of meningococcal vaccines in the National Immunization Program(NIP)over several years has significantly reduced the incidence of meningococcal meningitis in China to historic lows.Worldwide,there has been a diversification of meningococcal serogroups,leading to a shift in dominant serogroups in China from serogroup A to serogroups C and B,accompanied by a rise in reports of serogroups Y and W.What is added by this report?An outbreak of serogroup Y Neisseria meningitidis(Nm)in a secondary vocational school involved a single confirmed severe case and 24 individuals with laboratory-confirmed Nm carriage.Epidemiological investigation revealed that the outbreak was localized to the classroom of the confirmed case.Prolonged close contact within a confined space was identified as a significant risk factor for Nm transmission.The genotype sequence identified was type 1655(ST-1655),which is categorized under clonal complex 23(CC-23)and bears resemblance to 8 previously confirmed cases of serogroup Y meningococcal meningitis within Guangdong Province.This suggests that serogroup Y infections continue to sporadically emerge and have become prevalent strains.What are the implications for public health practice?This outbreak underscores the critical need to enhance surveillance of meningococcal serogroups and population carrier,and advocate for vaccination with MenY-containing vaccines. 展开更多
关键词 BREAK Secondary GUANGDONG
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Application of the sodium hyaluronate-CNTF scaffolds in repairing adult rat spinal cord injury and facilitating neural network formation 被引量:6
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作者 Yabin Xie Wei Song +6 位作者 Wen Zhao yudan Gao Junkui Shang Peng Hao Zhaoyang Yang Hongmei Duan Xiaoguang Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第5期559-568,共10页
The present study aimed to explore the potential of the sodium hyaluronate-CNTF (ciliary neurotrophic factor) scaffold in activating endogenous neurogenesis and facilitating neural network re-formation after the adult... The present study aimed to explore the potential of the sodium hyaluronate-CNTF (ciliary neurotrophic factor) scaffold in activating endogenous neurogenesis and facilitating neural network re-formation after the adult rat spinal cord injury (SCI). After completely cutting and removing a 5-mm adult rat T8 segment, a sodium hyaluronate-CNTF scaffold was implanted into the lesion area. Dil tracing and immunofluorescence staining were used to observe the proliferation, differentiation and integration of neural stem cells (NSCs) after SCI. A planar multielectrode dish system (MED64) was used to test the electrophysiological characteristics of the regenerated neural network in the lesioned area. Electrophysiology and behavior evaluation were used to evaluate functional recovery of paraplegic rat hindlimbs. The Dil tracing and immunofluorescence results suggest that the sodium hyaluronate-CNTF scaffold could activate the NSCs originating from the spinal cord ependymal, and facilitate their migration to the lesion area and differentiation into mature neurons, which were capable of forming synaptic contact and receiving glutamatergic excitatory synaptic input. The MED64 results suggest that functional synapsis could be established among regenerated neurons as well as between regenerated neurons and the host tissue, which has been evidenced to be glutamatergic excitatory synapsis. The electrophysiology and behavior evaluation results indicate that the paraplegic rats’ sensory and motor functions were recovered in some degree. Collectively, this study may shed light on paraplegia treatment in clinics. 展开更多
关键词 spinal cord injury endogenous neural stem cells neural network reconstruction CNTF new born neuron
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Determination of Total Flavonoids in Acanthopanax senticosus(Rupr. et Maxim.) Harms by Enzymolysis and Its Technological Optimization
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作者 Li Xinzhi Wang yudan +4 位作者 Wang Meiliang Liu Tianyang Gao Ruihua Qiu Youwen Zhang Shunjie 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期53-60,共8页
In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively... In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively analyzed. The ultrasonic extraction technology was optimized by Box-Behnken response surface method, and the total flavonoid content of 21 kinds of Acanthopanax senticosus(Rupr. et Maxim.) Harms from different producing areas were analyzed by cluster analysis. The optimal process conditions were determined as ultrasonic time 30 min, solid-liquid ratio 1 : 12 and ultrasonic power 250 W, and the average yield of the total flavonoid was 1.453 mg·g^ (-1). By optimizing the ultrasonic-assisted extraction method, the total flavonoid content from different producing areas was compared in the experiment, which provided certain data support for the optimization of the extraction process in the future and laid a certain theoretical foundation for the quality analysis of Chinese medicinal materials. 展开更多
关键词 Acanthopanax senticosus(Rupr.et Maxim.)Harms total flavonoid Box-Behnken response surface test ultrasonic-assisted extraction
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Identification and Characterization of a LEA-like Gene, CaMF5,Specifically Expressed in the Anthers of Male-fertile Capsicum annuum 被引量:6
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作者 yudan Wang Guoju Chen +2 位作者 Jianjun Lei Bihao Cao Changming Chen 《Horticultural Plant Journal》 2020年第1期39-48,共10页
To improve the understanding of molecular mechanisms of anther and/or pollen development in Chili pepper, in the present study, fulllength cDNA and DNA sequences of the pollen development-related gene CaMF5 were obtai... To improve the understanding of molecular mechanisms of anther and/or pollen development in Chili pepper, in the present study, fulllength cDNA and DNA sequences of the pollen development-related gene CaMF5 were obtained from the anthers of a Capsicum annuum nuclear male-fertile line. Sequence analysis indicated that the full length of CaMF5 was 747 bp, containing a maximum opening reading frame of 447 bp.Amino acid sequence alignment and phylogenetic analysis revealed that CaMF5 shared approximately 37%–77% homology with a series of uncharacterized or hypothetical proteins and late embryogenesis abundant(LEA) proteins from other plants. However, no LEA structural domain was detected in CaMF5, which indicated that it might be a new type of LEA gene. CaMF5 was only expressed in flower buds at stages 7 and 8 and in open flowers of the male-fertile line, whereas it exhibited no expression in any examined organs of the male-sterile line. In addition, CaMF5 showed the highest transcript abundance in the anthers of the male-fertile line, with no expression being detected in any other examined organs, such as the sepals, petals, pistils, roots, stems, or leaves. Taken together, our results suggest that CaMF5 is an anther-specific gene that might encode a new type of LEA protein related to anther and/or pollen development in C. annuum. 展开更多
关键词 Capsicum annuum CaMF5 Anther-specific gene Late embryogenesis abundant Expression analysis
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Sandbox Modeling of the Fault-increment Pattern in Extensional Basins 被引量:6
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作者 Geng Changbo Tong Hengmao +1 位作者 He yudan Wei Chunguang 《Petroleum Science》 SCIE CAS CSCD 2007年第2期29-34,共6页
Three series of sandbox modeling experiments were performed to study the fault-increment pattern in extensional basins. Experimental results showed that the tectonic action mode of boundaries and the shape of major bo... Three series of sandbox modeling experiments were performed to study the fault-increment pattern in extensional basins. Experimental results showed that the tectonic action mode of boundaries and the shape of major boundary faults control the formation and evolution of faults in extensional basins. In the process of extensional deformation, the increase in the number and length of faults was episodic, and every 'episode' experienced three periods, strain-accumulation period, quick fault-increment period and strain-adjustment period. The more complex the shape of the boundary fault, the higher the strain increment each 'episode' experienced. Different extensional modes resulted in different fault-increment patterns. The horizontal detachment extensional mode has the 'linear' style of fault-increment pattern, while the extensional mode controlled by a listric fault has the 'stepwise' style of fault-increment pattern, and the extensional mode controlled by a ramp-flat boundary fault has the 'stepwise-linear' style of fault-increment pattern. These fault-increment patterns given above could provide a theoretical method of fault interpretation and fracture prediction in extensional basins. 展开更多
关键词 Extensional basin sandbox modeling fault-increment pattern boundary fault
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Drought-triggered repression of miR166 promotes drought tolerance in soybean
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作者 Chen Zhao Jingjing Ma +7 位作者 Chen Yan Yu Jiang Yaohua Zhang yudan Lu Ye Zhang Suxin Yang Xianzhong Feng Jun Yan 《The Crop Journal》 SCIE CSCD 2024年第1期154-163,共10页
Drought stress limits agricultural productivity worldwide.Identifying and characterizing genetic components of drought stress-tolerance networks may improve crop resistance to drought stress.We show that the regulator... Drought stress limits agricultural productivity worldwide.Identifying and characterizing genetic components of drought stress-tolerance networks may improve crop resistance to drought stress.We show that the regulatory module formed by miR166 and its target gene,ATHB14-LIKE,functions in the regulation of drought tolerance in soybean(Glycine max).Drought stress represses the accumulation of miR166,leading to upregulation of its target genes.Optimal knockdown of miR166 in the stable transgenic line GmSTTM166 conferred drought tolerance without affecting yield.Expression of ABA signaling pathway genes was regulated by the miR166-mediated regulatory pathway,and ATHB14-LIKE directly activates some of these genes.There is a feedback regulation between ATHB14-LIKE and MIR166 genes,and ATHB14-LIKE inhibits MIR166 expression.These findings reveal that drought-triggered regulation of the miR166-mediated regulatory pathway increases plants drought resistance,providing new insights into drought stress regulatory network in soybean. 展开更多
关键词 SOYBEAN Drought stress miRNA ABA signaling
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Multi-junction cascaded vertical-cavity surface-emitting laser with a high power conversion efficiency of 74%
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作者 Yao Xiao Jun Wang +5 位作者 Heng Liu Pei Miao yudan Gou Zhicheng Zhang Guoliang Deng Shouhuan Zhou 《Light(Science & Applications)》 SCIE EI CSCD 2024年第3期555-565,共11页
High electro-optical conversion efficiency is one of the most distinctive features of semiconductor lasers as compared to other types of lasers.Its further increase remains a significant objective.Further enhancing th... High electro-optical conversion efficiency is one of the most distinctive features of semiconductor lasers as compared to other types of lasers.Its further increase remains a significant objective.Further enhancing the efficiency of edgeemitting lasers(EEL),which represent the highest efficiency among semiconductor lasers at present,is challenging.The efficiency of vertical cavity surface emitting lasers(VCSELs)has always been relatively low compared to EEL.This paper,combining modeling with experiments,demonstrates the potential of multi-junction cascaded VCSELs to achieve high efficiency beyond that of EELs,our simulations show,that a 20-junction VCSEL can achieve an efficiency of more than 88%at room temperature.We fabricated VCSEL devices with different numbers of junctions and compared their energy efficiency.15-junction VCSELs achieved a maximum efficiency of 74%at room temperature under nanosecond driving current,the corresponding differential quantum efficiency exceeds 1100%,being the largest electro-optical conversion efficiency and differential quantum efficiency reported until now for VCSELs. 展开更多
关键词 cascaded POWER CAVITY
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La_(2)O_(3)-promoted Ni/H-ZSM-5 catalyzed aqueous-phase guaiacol hydrodeoxygenation to cyclohexanol 被引量:1
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作者 Feng Lin yudan Zhong +3 位作者 Yulong Ma Yonggang Sun Xiuqin Men Yingbo Zhu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第2期224-232,共9页
Hydrodeoxygenation(HDO)of renewable lignin-derived biomass in aqueous-phase to produce high value-added products is of great significance.However,developing new catalysts with high activity and excellent stability in ... Hydrodeoxygenation(HDO)of renewable lignin-derived biomass in aqueous-phase to produce high value-added products is of great significance.However,developing new catalysts with high activity and excellent stability in an aqueous phase faces considerable challenges.Rare earth doping can effectively regulate the water exchange rate constant(WERC)value of the catalyst and play an important role in promoting the hydrolysis of ether bonds.Therefore,in this paper the bimetallic supported catalyst Ni-La_(2)O_(3)/H-ZSM-5 doped with rare earth metal La_(2)O_(3)was prepared,and used to catalyze the conversion of the lignin model co mpound guaiacol to cyclohexanol in the aqueous phase.The co nversion of guaiacol catalyzed by 10Ni-3La_(2)O_(3)/H-ZSM-5 reaches 100%,and the selectivity of the product cyclohexanol is 85%.A series of characterizations illustrate that the doping of La_(2)O_(3)causes the electron transfer between La_(2)O_(3)-Ni and changes the distribution of Ni,and a strong metal carrier interaction occurs between the bimetallic Ni-La_(2)O_(3)and H-ZSM-5.This can effectively promote the hydrolysis of the C-O ether bond in guaiacol and significantly improve the activity of the catalyst.The possible catalytic reaction mechanism of Ni-La_(2)O_(3)/H-ZSM-5 catalytic conversion of guaiacol was proposed. 展开更多
关键词 La_(2)O_(3) GUAIACOL Catalysis H-ZSM-5 Rare earths
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Chronic spinal cord injury repair by NT3-chitosan only occurs after clearance of the lesion scar 被引量:4
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作者 Can Zhao Jia-Sheng Rao +8 位作者 Hongmei Duan Peng Hao Junkui Shang Yubo Fan Wen Zhao yudan Gao Zhaoyang Yang Yi Eve Sun Xiaoguang Li 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2022年第7期2568-2580,共13页
Spinal cord injury(SCI)is a severe damage usually leading to limb dysesthesia,motor dysfunction,and other physiological disability.We have previously shown that NT3-chitosan could trigger an acute SCI repairment in ra... Spinal cord injury(SCI)is a severe damage usually leading to limb dysesthesia,motor dysfunction,and other physiological disability.We have previously shown that NT3-chitosan could trigger an acute SCI repairment in rats and non-human primates.Due to the negative effect of inhibitory molecules in glial scar on axonal regeneration,however,the role of NT3-chitosan in the treatment of chronic SCI remains unclear.Compared with the fresh wound of acute SCI,how to handle the lesion core and glial scars is a major issue related to chronic-SCI repair.Here we report,in a chronic complete SCI rat model,establishment of magnetic resonancediffusion tensor imaging(MR-DTI)methods to monitor spatial and temporal changes of the lesion area,which matched well with anatomical analyses.Clearance of the lesion core via suction of cystic tissues and trimming of solid scar tissues before introducing NT3-chitosan using either a rigid tubular scaffold or a soft gel form led to robust neural regeneration,which interconnected the severed ascending and descending axons and accompanied with electrophysiological and motor functional recovery.In contrast,cystic tissue extraction without scar trimming followed by NT3-chitosan injection,resulted in little,if any regeneration.Taken together,after lesion core clearance,NT3-chitosan can be used to enable chronic-SCI repair and MR-DTI-based mapping of lesion area and monitoring of ongoing regeneration can potentially be implemented in clinical studies for subacute/chronic-SCI repair. 展开更多
关键词 SCAR NT3 WOUND
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Effective Improvement of the Photovoltaic Performance of Carbon-Based Perovskite Solar Cells by Additional Solvents 被引量:5
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作者 Chenxi Zhang yudan Luo +3 位作者 Xiaohong Chen Yiwei Chen Zhuo Sun Sumei Huang 《Nano-Micro Letters》 SCIE EI CAS 2016年第4期347-357,共11页
A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber layers.It involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed... A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber layers.It involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed by the addition of chlorobenzene(CB).The method produced ultra-flat and dense perovskite capping layers atop mesoporous TiO_2 films,enabling a remarkable improvement in the performance of free hole transport material(HTM) carbon electrode-based perovskite solar cells(PSCs).Toluene(TO) was also studied as an additional solvent for comparison.At the annealing temperature of 100 °C,the fabricated HTM-free PSCs based on drop-casting CB demonstrated power conversion efficiency(PCE) of 9.73 %,which is 36 and 71 % higher than those fabricated from the perovskite films using TO or without adding an extra solvent,respectively.The interaction between the PbI_2–DMSO–CH_3NH_3I intermediate phase and the additional solvent was discussed.Furthermore,the influence of the annealing temperature on the absorber film formation,morphology,and crystalline structure was investigated and correlated with the photovoltaic performance.Highly efficient,simple,and stable HTM-free solar cells with a PCE of 11.44 % were prepared utilizing the optimum perovskite absorbers annealed at 120 °C. 展开更多
关键词 Halide perovskite Solar cell SPIN-COATING Carbon counter electrode Free hole transporting material
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Efficacy and mechanisms of Dingxian pill(定痫丸)combined with valproic acid on pentylenetetrazol-induced chronic epilepsy in rats 被引量:1
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作者 QU Dongxiao GE Yiqin +7 位作者 ZHUO Limin CHEN Liji XUE Yonghua CHENG Jiwei TAO Jie LI Guoyi ZHU yudan XIAO Qian 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2023年第2期286-294,共9页
OBJECIVE:To investigate the efficacy and mechanisms of Dingxian pill(定痫丸)combined with valproic acid(VPA)on pentylenetetrazol-induced chronical epilepsy in rats.METHODS:A rat model of epilepsy was established by ad... OBJECIVE:To investigate the efficacy and mechanisms of Dingxian pill(定痫丸)combined with valproic acid(VPA)on pentylenetetrazol-induced chronical epilepsy in rats.METHODS:A rat model of epilepsy was established by administering pentylenetetrazol(PTZ)water solution(35 mg/kg).Rats were divided into 4 groups,among which three groups were treated with different drugs once a day for 28 d including Dingxian pill(2.4 g/kg),VPA(0.2 g/kg),or a combination of Dingxian pill(2.4 g/kg)and VPA(0.2 g/kg)respectively,and the control group was given the same volume of saline.Rats in different groups were compared based on animal behavior,electroencephalograms,Morris water maze,immunohistochemistry,transcriptomics and real-time polymerase chain reaction.RSULTS:The combination therapy of Dingxian pill and VPA inhibited PTZ-induced seizure-like behavior and reduced seizure grades more significantly than VPA alone.Compared with the control group,the learning and memory ability of chronic PTZ-induced epileptic rats was improved in all the drug treatment groups,especially in the group that received both Dingxian pill and VPA.Similar to the results of MWM tests,expression of the neuroexcitability marker gene c-Fos was reduced after Dingxian pill and/or VPA treatment,and the effect was most pronounced in the combined treatment group.Transcriptomic analysis revealed that gene expression in the rodent hippocampus,which is involved in epilepsy,was upregulated by combined treatment with Dingxian pill and VPA,compared with VPA treatment alone.CONCLUSION:Our results not only highlight the antiepileptic effects of combined Dingxian pill and VPA treatment,but also shed light on the underlying molecular mechanisms and provide a way to apply Traditional Chinese Medicine in the treatment of epilepsy. 展开更多
关键词 EPILEPSY Valproic Acid learning memory TRANSCRIPTOME Dingxian pill
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Roles and Molecular Mechanisms of Biomarkers in Hepatocellular Carcinoma with Microvascular Invasion: A Review 被引量:1
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作者 Xudong Zhao yudan Wang +11 位作者 Haoming Xia Shuqiang Liu Ziyue Huang Risheng He Liang Yu Nanfeng Meng Hang Wang Junqi You Jinglin Li Judy Wai Ping Yam Yi Xu Yunfu Cui 《Journal of Clinical and Translational Hepatology》 SCIE 2023年第5期1170-1183,共14页
Hepatocellular carcinoma(HCC)being a leading cause of cancer-related death,has high associated mortality and recurrence rates.It has been of great necessity and urgency to find effective HCC diagnosis and treatment me... Hepatocellular carcinoma(HCC)being a leading cause of cancer-related death,has high associated mortality and recurrence rates.It has been of great necessity and urgency to find effective HCC diagnosis and treatment measures.Studies have shown that microvascular invasion(MVI)is an independent risk factor for poor prognosis after hepatectomy.The abnormal expression of biomacromolecules such as circ-RNAs,lncRNAs,STIP1,and PD-L1 in HCC patients is strongly correlated with MVI.Deregulation of several markers mentioned in this review affects the proliferation,invasion,metastasis,EMT,and anti-apoptotic processes of HCC cells through multiple complex mechanisms.Therefore,these biomarkers may have an important clinical role and serve as promising interventional targets for HCC.In this review,we provide a comprehensive overview on the functions and regulatory mechanisms of MVI-related biomarkers in HCC. 展开更多
关键词 Hepatocellular carcinoma Microvascular invasion Biomarkers PROGRESS Molecular mechanism
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