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Habitat types and functional traits mediate differentiated response of birds assemblage to super typhoon 认领 引用
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作者 Demeng Jiang Yi Zhou +4 位作者 Gang Lu Yu Chen Yan Li Zhiqin Zhou Xu Luo 《Avian Research》 SCIE CAS CSCD 2026年第3期612-619,共8页
The proportion of intense tropical cyclones is projected to increase under climate change,posing growing threats to global biodiversity.However,most existing research has been conducted in the North Atlantic region an... The proportion of intense tropical cyclones is projected to increase under climate change,posing growing threats to global biodiversity.However,most existing research has been conducted in the North Atlantic region and has focused on their impacts on natural habitats,whereas other cyclone-prone but biodiversity-rich and human-disturbed ecosystems have been overlooked.Moreover,while functional traits are important in mediating species'responses to habitat change,their role remains understudied in cyclone contexts.To address these issues,we assessed the differences in bird communities before and after a super typhoon across two coastal habitat types in Haikou,southern China:urban green space and suburban habitats.We evaluated species richness,total abundance,community composition,and how functional traits shaped species'resilience to a super typhoon.We recorded 45 species and 1627 individuals from the field survey of 101.5-km-long transects.Species richness remained stable in both habitats after the typhoon.Bird abundance at the transect level declined in both habitats,but this decline was significant only in suburban habitats;community composition also shifted in both habitats due to species replacement and concurrent population gains and losses.Functional trait analysis indicated that species with a higher hand-wing index,lower body mass,or open-country habitat association were more vulnerable.These findings highlight the heightened vulnerability of suburban habitats to cyclonic disturbances and underscore the importance of incorporating functional trait analysis and non-forest ecosystems into climate impact assessments to inform more holistic biodiversity conservation strategies. 展开更多
关键词 Avian communities Ecological vulnerability Functional traits Species turnover Suburban habitats Super typhoon Urban green space
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Effect of synergistic action of ultrasonic vibration and solidification pressure on tensile properties of vacuum counter-pressure casting aluminum alloy 认领 引用 被引量：7
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作者 Qing-song Yan Gang Lu +2 位作者 Gui-ming Luo Bo-wen Xiong Qiang-qiang Zheng 《China Foundry》 SCIE CAS 2018年第6期411-417,共7页
The effect of synergistic action of ultrasonic vibration and solidification pressure on tensile properties of vacuum counter-pressure casting ZL114 A alloys was studied systemically through testing and analyzing the t... The effect of synergistic action of ultrasonic vibration and solidification pressure on tensile properties of vacuum counter-pressure casting ZL114 A alloys was studied systemically through testing and analyzing the tensile strength and elongation subjected to different ultrasonic powers and solidification pressures. The results indicate that the synergistic action of ultrasonic vibration and solidification pressure can result in the refinement of grains and improvement of tensile properties. Both the highest tensile strength and elongation of aluminum alloy were obtained under synergistic action of 600 W ultrasonic power and 350 kPa solidification pressure. Moreover, the tensile fracture morphology shows obvious ductile fracture characteristics. When the solidification pressure is lower than 300 kPa, the effect of ultrasonic power on tensile strength and elongation is more obvious, but when the solidification pressure is higher than 300 kPa, the effect of solidification pressure on tensile strength and elongation is greater. Meanwhile, the size and morphology of the eutectic silicon were improved significantly by the ultrasonic vibration and pressurized solidification. The strip and massive eutectic silicon phase are completely converted into small short rod-like and evenly distributed Si phases at the grain boundary of primary α-Al. 展开更多
关键词 ultrasonic power solidification pressure vacuum counter-pressure casting aluminum alloy tensile property
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Diversity and independent evolutionary profiling of rodent-borne viruses in Hainan,a tropical island of China 认领 引用 被引量：4
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作者 Youyou Li Chuanning Tang +23 位作者 Yun Zhang Zihan Li Gaoyu Wang Ruoyan Peng Yi Huang Xiaoyuan Hu Henan Xin Boxuan Feng Xuefang Cao Yongpeng He Tonglei Guo Yijun He Haoxiang Su Xiuji Cui Lina Niu Zhiqiang Wu Jian Yang Fan Yang Gang Lu Lei Gao Qi Jin Meifang Xiao Feifei Yin Jiang Du 《Virologica Sinica》 SCIE CAS CSCD 2023年第5期651-662,共12页
The risk of emerging infectious diseases(EID)is increasing globally.More than 60%of EIDs worldwide are caused by animal-borne pathogens.This study aimed to characterize the virome,analyze the phylogenetic evolution,an... The risk of emerging infectious diseases(EID)is increasing globally.More than 60%of EIDs worldwide are caused by animal-borne pathogens.This study aimed to characterize the virome,analyze the phylogenetic evolution,and determine the diversity of rodent-borne viruses in Hainan Province,China.We collected 682 anal and throat samples from rodents,combined them into 28 pools according to their species and location,and processed them for next-generation sequencing and bioinformatics analysis.The diverse viral contigs closely related to mammals were assigned to 22 viral families.Molecular clues of the important rodent-borne viruses were further identified by polymerase chain reaction for phylogenetic analysis and annotation of genetic characteristics such as arenavirus,coronavirus,astrovirus,pestivirus,parvovirus,and papillomavirus.We identified pestivirus and bocavirus in Leopoldoms edwardsi from Huangjinjiaoling,and bocavirus in Rattus andamanensis from the national nature reserves of Bangxi with low amino acid identity to known pathogens are proposed as the novel species,and their rodent hosts have not been previously reported to carry these viruses.These results expand our knowledge of viral classification and host range and suggest that there are highly diverse,undiscovered viruses that have evolved independently in their unique wildlife hosts in inaccessible areas. 展开更多
关键词 Rodents Virome Phylogenetic analysis Novel viruses Wildlife
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Transactivation of the TIEG1 confers growth inhibition of transforming growth factor-β-susceptible hepatocellular carcinoma cells 认领 引用 被引量：13
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作者 Lei Jiang Yiu-Kay Lai +6 位作者 Jin-Fang Zhang Chu-Yan Chan Gang Lu Marie CM Lin Ming-Liang He Ji-Cheng Li Hsiang-Fu Kung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第17期2035-2042,共8页
AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines wi... AIM:To investigate the role of transforming growth factor(TGF)-β-inducible early gene 1(TIEG1) in TGF-β-induced growth inhibition in hepatocellular carcinoma(HCC) cells.METHODS:Human hepatocyte and HCC cell lines with varied susceptibilities to TGF-β1 were tested by methylthiazoletetrazolium(MTT) assay.The expression changes of Smad2,Smad3,Smad4,Smad7,TIEG1 and TIEG2 gene following treatment with TGF-β1 in a TGF-β-sensitive hepatocyte cell line(MIHA),a TGF-β-sensitive hepatoma cell line(Hep3B) and two TGF-β-insensitive hepatoma cell lines(HepG2 and Bel7404) were examined.SiRNA targeting TIEG1 was transfected into Hep3B cells and the sensitivity of cells to TGF-β1 was examined.Overexpression of TIEG1 was induced by lentiviral-mediated transduction in TGF-β1-resistant hepatoma cell lines(Bel7404 and HepG2).MTT assay and 4',6-Diamidino-2-phenylindole staining were used to identify cell viability and apoptosis,respectively.The expression level of stathmin was measured by reverse transcriptase polymerase chain reaction and Western-blotting analysis,and stathmin promoter activity by TIEG1 was monitored by a luciferase reporter gene system.RESULTS:TIEG1 was significantly upregulated by TGF-β1 in the TGF-β1-sensitive HCC cell line,Hep3B,but not in the resistant cell lines.The suppression of TIEG1 by siRNAs decreased the sensitivity of Hep3B cells to TGF-β1,whereas the overexpression of TIEG1 mediated growth inhibition and apoptosis in TGF-β1-resistant HCC cell lines,which resembled those of TGF-β1-sensitive HCC cells treated with TGF-β1.Our data further suggested that stathmin was a direct target of TIEG1,as stathmin was signif icantly downregulated by TIEG1 overexpression,and stathmin promoter activity was inhibited by TIEG1 in a dose-dependent manner.CONCLUSION:Our data suggest that transactivation of TIEG1 conferred growth inhibition of TGF-β-susceptible human HCC cells. 展开更多
关键词 Growth inhibition Hepatocellular carcinoma Stathmin Transforming growth factor-β Transforming growth factor-β-inducible early gene 1
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Protecting-group-dependent chemo-and regioselective cascade rearrangement of N-arylhydroxylamines with N-thiophthalimides 认领 引用
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作者 Zhaoquan Guo Wenyao Ding +3 位作者 Zhenguo Xi Lin Yang Gang Lu Hongyin Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第2期392-400,共9页
Sulfoxides and sulfide compounds have broad-spectrum biological properties and have received considerable attention in the past few decades.Herein we reported two metal and oxidant-free,practical and efficient methods... Sulfoxides and sulfide compounds have broad-spectrum biological properties and have received considerable attention in the past few decades.Herein we reported two metal and oxidant-free,practical and efficient methods for the synthesis of highly synthetically useful and structurally diverse ortho-aminoaryl sulfoxides and 3,4,5-trisubstituted oxazolones from readily accessible N-arylhydroxylamines and N-thiophthalimides.This rapid transformation occurred smoothly to achieve chemo-and regioselective cascade rearrangements due to the differences of the protecting-groups of the nitrogen atom of N-arylhydroxyamines.DFT studies suggested that the competing S-O and S-C bond formations via SN2 nucleophilic substitution are crucial for the observed protecting-group-dependent chemoselectivity.Subsequent applications have shown that these two protocols might be powerful tools for the construction of sulfur-containing complex molecules under simple conditions. 展开更多
关键词 Arylhydroxylamines N-Thiophthalimides Regioselectivity [2,3]-Sigmatropic rearrangement Oxazolones
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Retro aza-[2+2]cycloaddition as stereochemical editing logic for multi-substituted azacyclobutanes 认领 引用
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作者 Fujie Liu Yuzhu Yan +3 位作者 Xi Wang Lingfei Hu Gang Lu Tao Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第3期496-502,共7页
Multi-substituted azetidines have been an under-utilized bioisosteres in modern drug entities,due to the scarcity of mild and stereo-controllable synthetic methods.The state-of-art aza-[2+2]cycloaddition suffers from ... Multi-substituted azetidines have been an under-utilized bioisosteres in modern drug entities,due to the scarcity of mild and stereo-controllable synthetic methods.The state-of-art aza-[2+2]cycloaddition suffers from two drawbacks,namely limited C=N scope and the dearth of stereochemical control.Herein,we extend a photocatalytic direct N-heteroarene dearomative aza-[2+2]cycloaddition under white light via energy transfer mechanism.A key protonic solvent triggered retro aza-[2+2]cycloaddition process was discovered and utilized as a stereochemical editing logic to address the challenge of diastereomeric control(controlling three contiguous stereocenters). 展开更多
关键词 Dearomatization Retro aza-[2+2]cycloaddition Azacyclobutane Visible light catalysis
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Synthesis of Flurbiprofen via Suzuki Reaction Catalyzed by Palladium Charcoal in Water 认领 引用 被引量：2
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作者 Gang LU Robert FRANZEN +1 位作者 Xiao Jing YU You Jun XU 《Chinese Chemical Letters》 SCIE CAS 2006年第4期461-464,共4页
Flurbiprofen 1, an excellent nonsteroidal antiinflammatory drug, was synthesized in 5 steps in 69% overall yield. The key step of constructing the biaryl fragment was successfully achieved via Pd/C-catalyzed Suzuki co... Flurbiprofen 1, an excellent nonsteroidal antiinflammatory drug, was synthesized in 5 steps in 69% overall yield. The key step of constructing the biaryl fragment was successfully achieved via Pd/C-catalyzed Suzuki coupling reaction in water using sodium tetraphenylborate as phenylation reagent. 展开更多
关键词 Flurbiprofen Suzuki coupling Pd/C sodium tetraphenylborate.
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Density and solidification feeding model of vacuum counter-pressure cast aluminum alloy under grade-pressuring conditions 认领 引用 被引量：4
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作者 Qing-song Yan Huan Yu +2 位作者 Gang Lu Bo-wen Xiong Suai Xu 《China Foundry》 SCIE CAS 2016年第2期133-138,共6页
The density of vacuum counter-pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade pressure difference and time on the density of aluminum alloys was discussed, and th... The density of vacuum counter-pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade pressure difference and time on the density of aluminum alloys was discussed, and the solidification feeding model under grade-pressuring condition was established. The results indicate the grade-pressured solidification feeding ability of vacuum counter-pressure casting mainly depends on grade pressure difference and time. With the increase of grade pressure difference, the density of all the aluminum alloy samples increases, and the trend of change in density from the pouring gate to the top location is first decreasing gradually and then increasing. In addition, in obtaining the maximum density, the optimal grade-pressuring time is different for samples with different wall thicknesses, and the solidification time when the solid volume fraction of aluminum alloy reaches about 0.65 appears to be the optimal beginning time for gradepressuring. 展开更多
关键词 vacuum counter-pressure casting grade-pressuring density solidification feeding
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Extracellular vesicles from iPSC-MSCs alleviate chemotherapy-induced mouse ovarian damage via the ILK-PI3K/AKT pathway 认领 引用 被引量：7
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作者 Rui-Can Cao Yue Lv +7 位作者 Gang Lu Hong-Bin Liu Wuming Wang Chunlai Tan Xian-Wei Su Zhiqiang Xiong Jin-Long Ma Wai-Yee Chan 《Zoological Research》 SCIE CSCD 2023年第3期620-635,共16页
Chemotherapy can significantly reduce follicle counts in ovarian tissues and damage ovarian stroma,causing endocrine disorder,reproductive dysfunction,and primary ovarian insufficiency(POI).Recent studies have suggest... Chemotherapy can significantly reduce follicle counts in ovarian tissues and damage ovarian stroma,causing endocrine disorder,reproductive dysfunction,and primary ovarian insufficiency(POI).Recent studies have suggested that extracellular vesicles(EVs)secreted from mesenchymal stem cells(MSCs)exert therapeutic effects in various degenerative diseases.In this study,transplantation of EVs from human induced pluripotent stem cell-derived MSCs(iPSC-MSC-EVs)resulted in significant restoration of ovarian follicle numbers,improved granulosa cell proliferation,and inhibition of apoptosis in chemotherapy-damaged granulosa cells,cultured ovaries,and in vivo ovaries in mice.Mechanistically,treatment with i PSC-MSC-EVs resulted in up-regulation of the integrinlinked kinase(ILK)-PI3K/AKT pathway,which is suppressed during chemotherapy,most likely through the transfer of regulatory microRNAs(miRNAs)targeting ILK pathway genes.This work provides a framework for the development of advanced therapeutics to ameliorate ovarian damage and POI in female chemotherapy patients. 展开更多
关键词 Extracellular vesicles Premature ovarian insufficiency Human induced pluripotent stem cell-derived mesenchymal stem cells ILK-PI3K/AKT pathway
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Luteolin suppresses oral carcinoma 3(OC3) cell growth and migration via modulating polo-like kinase 1(PLK1) expression and cellular energy metabolism 认领 引用 被引量：1
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作者 Pengfei GAO Wentao ZHANG +5 位作者 Yujie LIN Ruijie LU Zijian LOU Gang LU Ruolang PAN Yunfang CHEN 《Journal of Zhejiang University-SCIENCE B》 SCIE CAS CSCD 2023年第12期1151-1158,共8页
Oral squamous cell carcinoma(OSCC)is a prevalent malignant tumor affecting the head and neck region(Leemans et al.,2018).It is often diagnosed at a later stage,leading to a poor prognosis(Muzaffar et al.,2021;Li et al... Oral squamous cell carcinoma(OSCC)is a prevalent malignant tumor affecting the head and neck region(Leemans et al.,2018).It is often diagnosed at a later stage,leading to a poor prognosis(Muzaffar et al.,2021;Li et al.,2023).Despite advances in OSCC treatment,the overall 5-year survival rate of OSCC patients remains alarmingly low,falling below 50%(Jehn et al.,2019;Johnson et al.,2020).According to statistics,only 50%of patients with oral cancer can be treated with surgery.Once discovered,it is more frequently at an advanced stage.In addition,owing to the aggressively invasive and metastatic characteristics of OSCC,most patients die within one year of diagnosis.Hence,the pursuit of novel therapeutic drugs and treatments to improve the response of oral cancer to medication,along with a deeper understanding of their effects. 展开更多
关键词 PLK1 metabolism drugs
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Role of feline ANP32 proteins in regulating polymerase activity of influenza A virus 认领 引用
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作者 Gang Lu Feiyan Zheng +5 位作者 Yuqing Xiao Ran Shao Jiajun Ou Xin Yin Shoujun Li Guihong Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3145-3158,共14页
Recently,increasing natural infection cases and experimental animal challenge studies demonstrated domestic cats are susceptible to multiple subtypes influenza A virus(IAV)infections.Notably,some subtype IAV strains c... Recently,increasing natural infection cases and experimental animal challenge studies demonstrated domestic cats are susceptible to multiple subtypes influenza A virus(IAV)infections.Notably,some subtype IAV strains could circulate in domestic cats after cross-species transmission and even infected humans,posing a threat to public health.Host factors related to viral polymerase activity could determine host range of IAV and acidic nuclear phosphoprotein 32(ANP32)is the most important one among them.However,role of cat-derived ANP32 on viral polymerase activity and host range of IAV is still unknown.In the present study,a total of 10 feline ANP32(feANP32)splice variants(including 5 feANP32A,3 feANP32B,and 2 feANP32E)were obtained from domestic cats by RT-PCR.Sequence alignment results demonstrated amino acid deletions and/or insertions occurred among feANP32 variants,but all feANP32 proteins were primarily localized to cell nucleus.Minigenome replication systems for several representative IAV strains were established and the support ability of feANP32 on IAV polymerase activity was estimated.The results indicated that most feANP32A and feANP32B splice variants were able to support all the tested IAV strains,though the support activity of a single feANP32 protein on polymerase activity varied among different IAV strains.In addition,the role of feANP32 in supporting H3N2 canine influenza virus was determined by investigating viral replication in vitro.Collectively,our study systematically investigated the support activity of feANP32 on IAV,providing a clue for further exploring the mechanism of susceptibility of cats to IAV. 展开更多
关键词 ANP32 influenza A virus feline cross-species transmission
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Achieving superior strength-ductility synergy of 2205 duplex stainless steel via dual-heterogeneous structure design 认领 引用 被引量：1
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作者 Wenxin Wang Xi Wang +5 位作者 Gang Lu Xutao Huang Bo Li Yujie Liu Jianjun Wang Chunming Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2025年第5期202-213,共12页
The trade-offbetween strength and ductility remains a persistent obstacle in the development of advanced structural materials.In the present study,a novel dual-heterogeneous structure with a bimodal grain distribution... The trade-offbetween strength and ductility remains a persistent obstacle in the development of advanced structural materials.In the present study,a novel dual-heterogeneous structure with a bimodal grain distribution in both ferrite and austenite phases was fabricated via cold rolling and partial recrystallization annealing on solution-treated 2205 duplex stainless steel(DSS).The processed steel exhibited superior mechanical properties,with the yield strength increasing from 586 MPa to 903 MPa,and the ultimate tensile strength from 796 MPa to 1082 MPa,while maintaining a high total elongation of 35.3%.Based on in-situ electron backscatter diffraction(EBSD)and scanning electron microscope(SEM)analyses,the microstructural deformation behavior and strengthening mechanisms of the dual-heterostructured 2205 DSS were elucidated.The outstanding combination of strength and ductility was ascribed to the synergistic effects of grain refinement,dislocation strengthening,and hetero-deformation induced(HDI)strengthening.Moreover,the high ductility in DSS was attributed to the coactivation of cross-slip systems in ferrite{110}and{112}along with the single-slip systems in austenite{111}.These findings provide a new strategy for the design and development of high-strength and ultra-high-strength DSSs. 展开更多
关键词 Heterostructured duplex stainless steel Bimodal grain Hetero-deformation induced hardening In-situ EBSD-SEM Slip system
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SlPPR138-mediated RNA editing of rpoC1 is essential for chloroplast development in tomato 认领 引用
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作者 Yichen Liu Chengwen Li +4 位作者 Xiuyang Si Tao Zou Ye Li Changtian Pan Gang Lu 《Horticulture Research》 SCIE CSCD 2025年第10期240-251,共12页
Leaf color is a crucial determinant of photosynthetic efficiency and crop yield,but the molecular mechanisms regulating chloroplast development in tomato remain incompletely understood.Here,we identified a novel tomat... Leaf color is a crucial determinant of photosynthetic efficiency and crop yield,but the molecular mechanisms regulating chloroplast development in tomato remain incompletely understood.Here,we identified a novel tomato mutant,gret1,that exhibits yellow cotyledons and young leaves that gradually turn green upon maturation.The gret1 mutant displays significantly reduced chlorophyll content and defective chloroplast development at early leaf stages,accompanied by changes in expression of genes involved in photosynthesis and chloroplast biogenesis.Genetic analysis revealed that the gret1 phenotype is controlled by a single recessive nuclear gene.Using map-based cloning,we identified SlPPR138,encoding a DYW-type pentatricopeptide repeat(PPR)protein,as the causal gene.A T-to-C point mutation in SlPPR138 causes a Cys-to-Arg substitution,which disrupts its function.Both genetic complementation and CRISPR/Cas9 knockout experiments validated that the gret1 phenotype is caused by the loss of SlPPR138.Mechanistically,we found that SlPPR138 mediates chloroplast RNA editing,particularly affecting the C-to-U editing efficiency of rpoC1,which encodes a core subunit of plastid-encoded RNA polymerase(PEP)complex.These findings demonstrate SlPPR138 is essential for early chloroplast development through RNA editing,providing new insights into the post-transcriptional regulation of photosynthesis in plants. 展开更多
关键词 photosynthetic efficiency tomato gret mutant crop yield SLPPR RNA editing chloroplast development yellow cotyledons
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Nickel-catalyzed reductive alkynylation of ketoimines via unstrained C-C bond activation 认领 引用
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作者 Tian-Zhang Wang Le-Yu Tang +3 位作者 Yu-Qiu Guan Lingfei Hu Gang Lu Yu-Feng Liang 《Chinese Chemical Letters》 SCIE CAS CSCD 2025年第11期336-344,共9页
The carbon-carbon bond is the one of the most fundamental and abundant bonds that exist in organic molecules,and the challenge of functionalization of carbon-carbon bond has always been a critical pursuit in organic s... The carbon-carbon bond is the one of the most fundamental and abundant bonds that exist in organic molecules,and the challenge of functionalization of carbon-carbon bond has always been a critical pursuit in organic synthesis.In recent years,there have been a growing number of studies on the C-C bond activation.Nevertheless,the metal-catalyzed cleavage of the C-C(O)bond in unstrained ketones has remained relatively underexplored due to the strong affinity of carbonyl groups for metals.In this study,we report a nickel-catalyzed strategy for the reductive alkynylation of ketoimines viaβ-carbon elimination.This method involves the conversion of aryl ketones into aryl ketoimines,thus expanding the toolbox of aryl electrophiles.The use of a N-heterocyclic carbene(NHC)ligand is crucial for this catalytic transformation.This discovery leads to a cross electrophile coupling reaction characterized by its operational simplicity,unique chemo-selectivity and excellent functional group tolerance.In addition,the approach has been effectively applied to the late-stage alkynylation of diverse pharmaceuticals.Ultimately,a series of comprehensive experiments and theoretical studies were conducted to provide insights into the reaction pathway,which supports the proposedβ-carbon elimination process. 展开更多
关键词 Unstrained C-C bond activation β-Carbon elimination Nickel catalyst Cross electrophile coupling Alkynylation
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Influence of temperature, stress, and grain size on behavior of nano-polycrystalline niobium 认领 引用
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作者 晏玉平 张柳亭 +2 位作者 张丽攀 芦刚 涂志新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期467-474,共8页
Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS)... Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS) on creep properties and mechanisms are investigated. Notably, the occurrence of tertiary creep is exclusively observed under conditions where the applied stress exceeds 4.5 GPa and the temperature is higher than 1100 K. This phenomenon can be attributed to the significant acceleration of grain boundary and lattice diffusion, driven by the elevated temperature and stress levels. It is found that the strain rate increases with both temperature and stress increasing. However, an interesting trend is observed in which the strain rate decreases as the grain size increases. The stress and temperature are crucial parameters governing the creep behavior. As these factors intensify, the creep mechanism undergoes a sequential transformation: initially from lattice diffusion under low stress and temperature conditions to a mixed mode combining grain boundaries(GBs) and lattice diffusion at moderate stress and mid temperature levels, and ultimately leading to the failure of power-law controlled creep behavior, inclusive of grain boundary recrystallization under high stress and temperature conditions. This comprehensive analysis provides in more detail an understanding of the intricate creep behavior of nano-polycrystalline niobium and its dependence on various physical parameters. 展开更多
关键词 creep behavior molecular dynamics simulation activation energy stress exponent nano-polycrystalline niobium
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Complete genome sequence of the rifamycin SV-producing Amycolatopsis mediterranei U32 revealed its genetic characteristics in phylogeny and metabolism 认领 引用 被引量：14
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作者 Wei Zhao Yi Zhong +23 位作者 Hua Yuan Jin Wang Huajun Zheng Ying Wang Xufeng Cen Feng Xu Jie Bai Xiaobiao Han Gang Lu Yongqiang Zhu Zhihui Shao Han Yan Chen Li Nanqiu Peng Zilong Zhang Yunyi Zhang Wei Lin Yun Fan Zhongjun Qin Yongfei Hu Baoli Zhu Shengyue Wang Xiaoming Ding Guo-Ping Zbao 《Cell Research》 SCIE CAS 2010年第10期1096-1108,共13页
Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strai... Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strain U32 comprising 10 236 715 base pairs, is one of the largest prokaryotic genomes ever sequenced so far. Unlike the linear topology found in streptomycetes, this chromosome is circular, particularly similar to that of Saccharopolyspora erythraea and Nocardia farcinica, representing their close relationship in phylogeny and taxonomy. Although the predicted 9 228 protein-coding genes in the A. mediterranei genome shared the greatest number of orthologs with those of S. erythraea, it was unexpectedly followed by Streptomyces coelicolor rather than N. farcinica, indicating the distinct metabolic characteristics evolved via adaptation to diverse ecological niches. Besides a core region analogous to that common in streptomycetes, a novel ＇quasicore＇ with typical core characteristics is defined within the non-core region, where 21 out of the total 26 gene clusters for secondary metabolite production are located. The rifamycin biosynthesis gene cluster located in the core encodes a cytochrome P450 enzyme essential for the conversion of rifamycin SV to B, revealed by comparing to the highly homologous cluster of the rifamycin B-producing strain S699 and further confirmed by genetic complementation. The genomic information of A. mediterranei demonstrates a metabolic network orchestrated not only for extensive utilization of various carbon sources and inorganic nitrogen compounds but also for effective funneling of metabolic intermediates into the secondary antibiotic synthesis process under the control of a seemingly complex regulatory mechanism. 展开更多
关键词 genome Amycolatopsis mediterranei rifamycin phylogeny P450 metabolism
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Microglia activation,classification and microglia-mediated neuroinflammatory modulators in subarachnoid hemorrhage 认领 引用 被引量：6
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作者 Junfan Chen Zhiyuan Vera Zheng +3 位作者 Gang Lu Wai Yee Chan Yisen Zhang George Kwok Chu Wong 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第7期1404-1411,共8页
Subarachnoid hemorrhage is a devastating disease with significant mortality and morbidity,despite advances in treating cerebral aneurysms.There has been recent progress in the intensive care management and monitoring ... Subarachnoid hemorrhage is a devastating disease with significant mortality and morbidity,despite advances in treating cerebral aneurysms.There has been recent progress in the intensive care management and monitoring of patients with subarachnoid hemorrhage,but the results remain unsatisfactory.Microglia,the resident immune cells of the brain,are increasingly recognized as playing a significant role in neurological diseases,including subarachnoid hemorrhage.In early brain injury following subarachnoid hemorrhage,microglial activation and neuroinflammation have been implicated in the development of disease complications and recovery.To understand the disease processes following subarachnoid hemorrhage,it is important to focus on the modulators of microglial activation and the pro-inflammatory/anti-inflammatory cytokines and chemokines.In this review,we summarize research on the modulators of microglia-mediated inflammation in subarachnoid hemorrhage,including transcriptome changes and the neuroinflammatory signaling pathways.We also describe the latest developments in single-cell transcriptomics for microglia and summarize advances that have been made in the transcriptome-based classification of microglia and the implications for microglial activation and neuroinflammation. 展开更多
关键词 activation inflammation microglia modulator neuroinflammation sequencing signal pathway single-cell analysis stroke subarachnoid hemorrhage treatment
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Glial cell-derived neurotrophic factor mRNA expression in a rat model of spinal cord injury following bone marrow stromal cell transplantation 认领 引用 被引量：14
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作者 Lei Li Gang Lu +4 位作者 Yanfeng Wang Hong Gao Xin Xu Lunhao Bai Huan Wang 《Neural Regeneration Research》 SCIE CAS 2008年第10期1056-1059,共4页
BACKGROUND:Several animal experiments utilizing bone marrow stromal cell(BMSC)transplantation for the treatment of spinal cord injury have proposed a hypothesis that BMSC transplantation effects are associated with in... BACKGROUND:Several animal experiments utilizing bone marrow stromal cell(BMSC)transplantation for the treatment of spinal cord injury have proposed a hypothesis that BMSC transplantation effects are associated with increased glial cell-derived neurotrophic factor(GDNF)expression.OBJECTIVE:To confirm the effects of BMSC transplantation on GDNF mRNA expression in rats with spinal cord injury by reverse transcription-polymerase chain reaction(RT-PCR).DESIGN,TIME AND SETTING:The present molecular,cell biology experiment was performed at the Key Laboratory of Children's Congenital Malformation,Ministry of Health of China&Department of Developmental Biology,Basic Medical College,China Medical University between March 2006 and May 2007.MATERIALS:Sixty healthy Wistar rats aged 2-4-months and of either gender were included in this study.Spinal cord injury was induced in all rats by hemisection of T9 on the left side.RT-PCR kits were purchased from TaKaRa Company,China.Type 9600 RCR amplifier was provided by Perkin Elmer Company,USA.METHODS:Three rats were selected for BMSC culture and subsequent transplantation(after three passages).Of the remaining 57 rats,nine were selected for sham-operation(sham-operated group),where only the T9 spinal cord was exposed without hemisection.A total of 48 rats were randomly and evenly divided into BMSC transplantation and model groups.In the BMSC transplantation group,following spinal cord injury induction,each rat was administered a BMSC suspension tbrougb two injection sites selected on the gray and white matter boundary caudally and cephalically,seperately and near to injury site in the spinal cord.The model group received an equal volume of PBS through the identical injection sites.MAIN OUTCOME MEASURES:At 24 and 72 hours,as well as at 7 days,following spinal cord injury,the spinal cord at the T9 segment was removed.Eight rats were allocated to each time point in the BMSC transplantation and model groups,with three rats allocated to the sham-operated group.GDNF mRNA expression was semiquantitatively analyzed by RT-PCR.RESULTS:The sham-operated group exhibited extremely low GDNF mRNA expression.GDNF mRNA expression significantly increased at 24 hours after spinal cord injury,reached a peak level at 72 hours,and slowly decreased thereafter.However,it remained higher than normal levels at 7 days(P〈0.05).At all time points following spinal cord injury,GDNF mRNA expression was significantly greater in the BMSC transplantation group than in the model group(P〈0.05).CONCLUSION:Transplantation of BMSCs into the injured spinal cord up-regulated GDNF mRNA expression,thereby promoting repair of the injured spinal cord. 展开更多
关键词 bone marrow stromal cells neurotrophic factors spinal cord injury transplantation
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Reviewing subduction initiation and the origin of plate tectonics:What do we learn from present-day Earth? 认领 引用 被引量：10
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作者 Gang Lu Liang Zhao +2 位作者 Ling Chen Bo Wan FuYuan Wu 《Earth and Planetary Physics》 EI CAS CSCD 2021年第2期123-140,共18页
The theory of plate tectonics came together in the 1960s,achieving wide acceptance after 1968.Since then it has been the most successful framework for investigations of Earth’s evolution.Subduction of the oceanic lit... The theory of plate tectonics came together in the 1960s,achieving wide acceptance after 1968.Since then it has been the most successful framework for investigations of Earth’s evolution.Subduction of the oceanic lithosphere,as the engine that drives plate tectonics,has played a key role in the theory.However,one of the biggest unanswered questions in Earth science is how the first subduction was initiated,and hence how plate tectonics began.The main challenge is how the strong lithosphere could break and bend if plate tectonics-related weakness and slab-pull force were both absent.In this work we review state-of-the-art subduction initiation(SI)models with a focus on their prerequisites and related driving mechanisms.We note that the plume-lithosphere-interaction and mantleconvection models do not rely on the operation of existing plate tectonics and thus may be capable of explaining the first SI.Reinvestigation of plate-driving mechanisms reveals that mantle drag may be the missing driving force for surface plates,capable of triggering initiation of the first subduction.We propose a composite driving mechanism,suggesting that plate tectonics may be driven by both subducting slabs and convection currents in the mantle.We also discuss and try to answer the following question:Why has plate tectonics been observed only on Earth? 展开更多
关键词 subduction initiation plate tectonics mantle convection driving force mantle drag
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Identification of coastal wetlands of international importance for waterbirds:a review of China Coastal Waterbird Surveys 2005–2013 认领 引用 被引量：42
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作者 Qingquan Bai Jianzhong Chen +23 位作者 Zhihong Chen Guotai Dong Jiangtian Dong Wenxiao Dong Vivian Wing Kan Fu Yongxiang Han Gang Lu Jing Li Yang Liu Zhi Lin Derong Meng Jonathan Martinez Guanghui Ni Kai Shan Renjie Sun Suixing Tian Fengqin Wang Zhiwei Xu Yat-tung Yu Jin Yang Zhidong Yang Lin Zhang Ming Zhang Xiangwu Zeng 《Chinese Birds》 CSCD 2015年第3期153-168,共16页
Background:China's coastal wetlands belong to some of the most threatened ecosystems worldwide.The loss and degradation of these wetlands seriously threaten waterbirds that depend on wetlands.Methods:The China Coa... Background:China's coastal wetlands belong to some of the most threatened ecosystems worldwide.The loss and degradation of these wetlands seriously threaten waterbirds that depend on wetlands.Methods:The China Coastal Waterbird Census was organized by volunteer birdwatchers in China's coastal region.Waterbirds were surveyed synchronously once every month at 14 sites,as well as irregularly at a further 18 sites,between September 2005 and December 2013.Results:A total of 75 species of waterbirds met the 1 % population level Ramsar listing criterion at least once at one site.The number of birds of the following species accounted for over 20 % of the total flyway populations at a single site:Mute Swan(Cygnus olor),Siberia Crane(Grus leucogeranus),Far Eastern Oystercatcher(Haematopus osculans),Bar-tailed Godwit(Limosa lapponica),Spotted Greenshank(Tringa guttifer),Great Knot(Calidris tenuirostris),Spoon-billed Sandpiper(Calidris pygmeus),Saunders' s Gull(Larus saundersi),Relict Gull(Larus relictus),Great Cormorant(Phalacrocorax carbo),Eurasian Spoonbill(Platalea leucorodia),Black-faced Spoonbill(Platalea minor) and Dalmatian Pelican(Pelecanus crispus).A total of 26 sites supported at least one species of which their number met the1 % criterion.Forty-two species met the 1 % criterion in the Yellow River Delta,Shandong;29 at the Cangzhou coast,Hebei and 26 species at the Lianyungang coast,Jiangsu.Conclusions:The results highlight the international importance of China's coastal wetlands for waterbirds.This study also demonstrates that participation of local birdwatchers in waterbird surveys results in data that are invaluable not only for understanding the current status of waterbirds in China's coastal regions but also for waterbird conservation and management. 展开更多
关键词 1 criterion Citizen science Coastal wetlands Ramsar site Waterbirds
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