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A Golden2-like transcription factor, BnGLK1a, improves chloroplast development, photosynthesis, and seed weight in rapeseed
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作者 Qianwei zhang Yuanyi Mao +11 位作者 Zikun Zhao Xin Hu Ran Hu Nengwen Yin Xue Sun Fujun Sun si chen Yuxiang jiang Liezhao Liu Kun Lu Jiana Li Yu Pan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1481-1493,共13页
Enhancing photosynthetic efficiency is a major goal for improving crop yields under agricultural field conditions and is associated with chloroplast biosynthesis and development.In this study,we demonstrate that Golde... Enhancing photosynthetic efficiency is a major goal for improving crop yields under agricultural field conditions and is associated with chloroplast biosynthesis and development.In this study,we demonstrate that Golden2-like 1a(BnGLK1a)plays an important role in regulating chloroplast development and photosynthetic efficiency.Overexpressing BnGLK1a resulted in significant increases in chlorophyll content,the number of thylakoid membrane layers and photosynthetic efficiency in Brassica napus,while knocking down BnGLK1a transcript levels through RNA interference(RNAi)had the opposite effects.A yeast two-hybrid screen revealed that BnGLK1a interacts with the abscisic acid receptor PYRABACTIN RESISTANCE 1-LIKE 1-2(BnPYL1-2)and CONSTITUTIVE PHOTOMORPHOGENIC 9 SIGNALOSOME 5A subunit(BnCSN5A),which play essential roles in regulating chloroplast development and photosynthesis.Consistent with this,BnGLK1a-RNAi lines of B.napus display hypersensitivity to the abscisic acid(ABA)response.Importantly,overexpression of BnGLK1a resulted in a 10%increase in thousand-seed weight,whereas seeds from BnGLK1a-RNAi lines were 16%lighter than wild type.We propose that BnGLK1a could be a potential target in breeding for improving rapeseed productivity.Our results not only provide insights into the mechanisms of BnGLK1a function,but also offer a potential approach for improving the productivity of Brassica species. 展开更多
关键词 Brassica napus BnGLK1a chloroplast development photosynthetic efficiency YIELD
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High Fe‑Loading Single‑Atom Catalyst Boosts ROS Production by Density Effect for Efficient Antibacterial Therapy
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作者 si chen Fang Huang +5 位作者 Lijie Mao Zhimin Zhang Han Lin Qixin Yan Xiangyu Lu Jianlin Shi 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期187-203,共17页
The current single-atom catalysts(SACs)for medicine still suffer from the limited active site density.Here,we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs ... The current single-atom catalysts(SACs)for medicine still suffer from the limited active site density.Here,we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs by exchanging zinc with iron.The constructed iron SACs(h^(3)-FNC)with a high metal loading of 6.27 wt%and an optimized adjacent Fe distance of~4 A exhibit excellent oxidase-like catalytic performance without significant activity decay after being stored for six months and promising antibacterial effects.Attractively,a“density effect”has been found at a high-enough metal doping amount,at which individual active sites become close enough to interact with each other and alter the electronic structure,resulting in significantly boosted intrinsic activity of single-atomic iron sites in h^(3)-FNCs by 2.3 times compared to low-and medium-loading SACs.Consequently,the overall catalytic activity of h^(3)-FNC is highly improved,with mass activity and metal mass-specific activity that are,respectively,66 and 315 times higher than those of commercial Pt/C.In addition,h^(3)-FNCs demonstrate efficiently enhanced capability in catalyzing oxygen reduction into superoxide anion(O_(2)·^(−))and glutathione(GSH)depletion.Both in vitro and in vivo assays demonstrate the superior antibacterial efficacy of h^(3)-FNCs in promoting wound healing.This work presents an intriguing activity-enhancement effect in catalysts and exhibits impressive therapeutic efficacy in combating bacterial infections. 展开更多
关键词 Nanocatalytic medicine Single-atom catalysts Reactive oxygen species(ROS) High metal loading Oxidase catalysis
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Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH_(2)/Nafion composite membranes
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作者 Xu Li Dongwei Zhang +7 位作者 si chen Yingzhao Geng Yong Liu Libing Qian Xi chen Jingjing Li Pengfei Fang Chunqing He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1734-1746,共13页
High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which ... High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which exhibits a superior proton conductivity.PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes.Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated.Significant enhancement in proton conduction for PCP-MCN around 55℃ is interestingly found due to the thermal motion of the PCP molecular chains.Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains,i.e.,the formation of substantial acid–base pairs(-SO_(3)^(-)…^(+)H–NH-),which further improves compatibility between additive and Nafion matrix.At the same humidity and temperature condition,the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion.Proton conductivity(σ)over wide ranges of humidities(30-100%RH at 25℃)and temperatures(30-98℃ at 100%RH)for prepared membranes is measured.The s in PCPMCN/Nafion composite membranes is remarkably enhanced,i.e.0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98℃ and 100%RH,because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation–deprotonation processes.The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN.In particular,when 3 wt.%PCP-MCN was added to Nafion,the power density of a single-cell fabricated with this composite membrane reaches impressively 0.480,1.098 W/cm^(2) under 40%RH,100%RH at 60℃,respectively,guaranteeing it to be a promising proton exchange membrane. 展开更多
关键词 Nafion composite membrane Surface-modified MIL-101-Cr-NH_(2) Proton conductivity Single-cell performance
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Combined QTL mapping,GWAS and transcriptomic analysis revealed a candidate gene associated with the timing of spring bud flush in tea plant(Camellia sinensis) 被引量:2
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作者 Yujie Liu si chen +7 位作者 chenkai Jiang Haoran Liu Junyu Wang Weizhong He Doogyung Moon Jiedan chen Liang chen Jianqiang Ma 《Horticulture Research》 SCIE CSCD 2023年第9期275-277,共3页
Dear Editor,The timing of the spring bud f lush(TBF)is a crucial agro-nomic trait for the tea plant,as it strongly influences the yield and economic value of harvested fresh tea leaves.The TBF of tea plant is generall... Dear Editor,The timing of the spring bud f lush(TBF)is a crucial agro-nomic trait for the tea plant,as it strongly influences the yield and economic value of harvested fresh tea leaves.The TBF of tea plant is generally defined as the date when>30%of the growing tender shoots have reached the stage of one bud with one to three leaves,referred as to the stage of one and a bud,two and a bud,and three and a bud,respectively. 展开更多
关键词 SPRING mapping analysis
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Analysis of echo signal modulation characteristic parameters on aerial and space targets
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作者 si chen Hai-yang Zhang +3 位作者 Chang-ming Zhao Yu Fan Hong chen Lin Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期146-154,共9页
Based on the scattering characteristic,the comparison of RCS(radar cross-section)at different positions of a target in the same direction of incidence can be obtained first by extruding or deleting part of the entity.... Based on the scattering characteristic,the comparison of RCS(radar cross-section)at different positions of a target in the same direction of incidence can be obtained first by extruding or deleting part of the entity.A simulation method of aerial&space targets echo characteristics(A&STEC)is proposed that is universal to aerial and space targets.We utilize a fixed-wing UAV(unmanned aerial vehicle)and typical missiles in simulation.The echo signal modulation characteristic parameters are calculated theoretically by the atmospheric attenuation model,the finite element method and a MUMPS solver.The verification simulations show that this method can analyze the influence of the target shape,incident direction,detection position and detection frequency on echo waveform,intensity and energy distribution.The results show that the profile of echo waveform can invert the general shape of the target.The relationship between time and intensity can determine whether the target is moving towards or away from the detector in addition.These conclusions can provide a reference for the ballistic missile target tracking and the defense against UVA intrusion in theory. 展开更多
关键词 Echo signal modulation characteristic parameters Simple targets The fixed-wing UVA Missiles Scattering characteristics
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BnbHLH92a negatively regulates anthocyanin and proanthocyanidin biosynthesis in Brassica napus
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作者 Ran Hu Meichen Zhu +13 位作者 si chen chengxiang Li Qianwei Zhang Lei Gao Xueqin Liu Shulin Shen Fuyou Fu Xinfu Xu Ying Liang Liezhao Liu Kun Lu Hao Yu Jiana Li Cunmin Qu 《The Crop Journal》 SCIE CSCD 2023年第2期374-385,共12页
Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription fact... Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription factors involved in the regulation of anthocyanin and PAs biosynthesis have been characterized in rapeseed.In this study,we identified a transcription factor gene BnbHLH92a(BnaA06T0441000ZS)in rapeseed.Overexpressing BnbHLH92a both in Arabidopsis and in rapeseed reduced levels of anthocyanin and PAs.Correspondingly,the expression profiles of anthocyanin and PA biosynthesis genes(TT3,BAN,TT8,TT18,and TTG1)were shown by quantitative real-time PCR to be inhibited in BnbHLH92a-overexpressing Arabidopsis seeds,indicating that BnbHLH92a represses the anthocyanin and PA biosynthesis pathway in Arabidopsis.BnbHLH92a physically interacts with the BnTTG1 protein and represses the biosynthesis of anthocyanins and PAs in rapeseed.BnbHLH92a also binds directly to the BnTT18 promoter and represses its expression.These results suggest that BnbHLH92a is a novel upstream regulator of flavonoid biosynthesis in B.napus. 展开更多
关键词 Brassica napus L BnbHLH92a ANTHOCYANIN PROANTHOCYANIDINS Flavonoid pathway
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Tensile Properties and Prediction Model of Recombinant Bamboo at Different Temperatures
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作者 Kunpeng Zhao Yang Wei +2 位作者 si chen Kang Zhao Mingmin Ding 《Journal of Renewable Materials》 SCIE EI 2023年第6期2695-2712,共18页
The destruction of recombinant bamboo depends on many factors,and the complex ambient temperature is an important factor affecting its basic mechanical properties.To investigate the failure mechanism and stress–strai... The destruction of recombinant bamboo depends on many factors,and the complex ambient temperature is an important factor affecting its basic mechanical properties.To investigate the failure mechanism and stress–strain relationship of recombinant bamboo at different temperatures,eighteen tensile specimens of recombinant bamboo were tested.The results showed that with increasing ambient temperature,the typical failure modes of recombinant bamboo were flush fracture,toothed failure,and serrated failure.The ultimate tensile strength,ultimate strain and elastic modulus of recombinant bamboo decreased with increasing temperature,and the ultimate tensile stress decreased from 154.07 to 96.55 MPa,a decrease of 37.33%,and the ultimate strain decreased from 0.011 to 0.008,a decrease of 26.57%.Based on the Ramberg-Osgood model and the pseudo‒elastic design method,a predictive model was established for the tensile stress–strain relationship of recombinant bamboo considering the temperature level.The model can accurately evaluate the tensile stress–strain relationship of recombinant bamboo under different temperature conditions. 展开更多
关键词 Recombinant bamboo TEMPERATURE tensile behaviour stress-strain relationship predictive model
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Per1/Per2 double knockout transcriptome analysis reveals circadian regulation of hepatic lipid metabolism
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作者 Yiran Bu si chen +6 位作者 Mengcheng Ruan Libang Wu Hualin Wang Na Li Xiuju Zhao Xiaoli Yu Zhiguo Liu 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1716-1729,共14页
Scope: Circadian disorder and high-fat diet(HFD)can disturb lipid metabolism homeostasis and may promote the development of various metabolic diseases. The relationship between them is of great concern. This study aim... Scope: Circadian disorder and high-fat diet(HFD)can disturb lipid metabolism homeostasis and may promote the development of various metabolic diseases. The relationship between them is of great concern. This study aimed to explore the effects of Per1/Per2 double knockout(DKO)on hepatic lipid metabolism in mice under HFD and HFD with docosahexaenoic acid(DHA)substitution. Methods and results: Both wild type(WT)and DKO male C57BL/6 mice were fed with normal chow diet(CON), HFD, or HFD with DHA substitution(AO)for 15 weeks. At the end of the experiment, mice were sacrificed at zeitgeber time(ZT)0(7:00 am)or ZT12(7:00 pm). Pathological indicators were determined using histological and biochemical methods. Hepatic transcriptome sequencing analysis showed that DKO mice exhibited multiple dysfunctions in diurnal rhythm, drug metabolism, cell cycle, cancer pathways, and lipid metabolism. HFD had greater effects on fatty acid oxidation and cholesterol synthesis and metabolism in Per1-/-Per2-/-mice, which was improved by DHA substitution. Conclusions: Per1/Per2 played an important role in the circadian regulation of hepatic lipid metabolism, and DKO mice were more sensitive to HFD. DHA can improve circadian-related lipid metabolism disruption induced by HFD in mice. 展开更多
关键词 DHA High-fat diet Lipid metabolism Per1/Per2 TRANSCRIPTOMICS
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Ginsenoside F1 administration promotes UCP1-dependent fat browning and ameliorates obesity-associated insulin resistance
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作者 Yuhan Meng Weili Li +7 位作者 chenxing Hu si chen Haiyang Li Feifei Bai Lujuan Zheng Ye Yuan Yuying Fan Yifa Zhou 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2061-2072,共12页
Obesity-induced type 2 diabetes is mainly due to excessive free fatty acids leading to insulin resistance.Increasing thermogenesis is regarded as an effective strategy for hypolipidemia and hypoglycemia.Ginsenoside is... Obesity-induced type 2 diabetes is mainly due to excessive free fatty acids leading to insulin resistance.Increasing thermogenesis is regarded as an effective strategy for hypolipidemia and hypoglycemia.Ginsenoside is a natural active component in Panax ginseng C.A.Meyer,and some of them enhance thermogenesis.However,there are few studies on the mechanism and target of ginsenosides enhancing thermogenesis.Using thermogenic protein uncoupling protein 1(UCP1)-luciferase reporter assay,we identifi ed ginsenoside F1 as a novel UCP1 activator in the ginsenosides library.Using pull down assay and inhibitor interference,we found F1 binds toβ3-adrenergic receptors(β3-AR)to enhance UCP1 expression via cAMP/PKA/CREB pathway.We also investigated the ability of F1 on energy metabolism in obesity-induced diabetic mice,including body weight,body composition and energy expenditure.The results of proteomics showed that F1 signifi cantly up-regulated thermogenesis proteins and lipolytic proteins,but down-regulated fatty acid synthesis proteins.Ginsenoside F1 increased thermogenesis and ameliorated insulin resistance specifi cally by promoting the browning of white adipose tissue in obese mice.Additionally,ginsenoside F1 improves norepinephrine-induced insulin resistance in adipocytes and hepatocytes,and shows a stronger mitochondria respiration ability than norepinephrine.These fi ndings suggest that ginsenoside F1 is a promising lead compound in the improvement of insulin resistance. 展开更多
关键词 Ginsenoside F1 Uncoupling protein 1 β3-Adrenergic receptor White adipose tissue browning Insulin resistance
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Quality influencing factors of dispersion curves from short period dense arrays based on a convolutional neural network across the north section of the Xiaojiang fault area
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作者 si chen Rui Gao +5 位作者 Zhanwu Lu Yao Liang Wei Cai Lifu Cao Zilong chen Guangwen Wang 《Earthquake Science》 2023年第3期200-211,共12页
The number of dispersion curves increases significantly when the scale of a short-period dense array increases.Owing to a substantial increase in data volume,it is important to quickly evaluate dispersion curve qualit... The number of dispersion curves increases significantly when the scale of a short-period dense array increases.Owing to a substantial increase in data volume,it is important to quickly evaluate dispersion curve quality as well as select the available dispersion curve.Accordingly,this study quantitatively evaluated dispersion curve quality by training a convolutional neural network model for ambient noise tomography using a short-period dense array.The model can select high-quality dispersion curves that exhibit a≤10%difference between the results of manual screening and the proposed model.In addition,this study established a dispersion curve loss function by analyzing the quality of the dispersion curve and the corresponding influencing factors,thereby estimating the number of available dispersion curves for the existing observation systems.Furthermore,a Monte Carlo simulation experiment is used to illustrates the station-pair interval distance probability density function,which is independent of station number in the observational system with randomly deployed stations.The results suggested that the straight-line length should exceed 15 km to ensure that loss rate of dispersion curves remains<0.5,while maintaining the threshold ambient noise tomography accuracy within the study area. 展开更多
关键词 convolutional neural network ambient noise tomography dispersion curve
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Mannogalactoglucan from mushrooms protects pancreatic islets via restoring UPR and promotes insulin secretion in TIDM mice
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作者 Ting Liu si chen +7 位作者 Yunhe Qu Lujuan Zheng Xiaoxuan Yang Shuhan Men Yuanning Wang Hanrui Ma Yifa Zhou Yuying Fan 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1390-1401,共12页
Type 1 diabetes mellitus(T1DM) lacks insulin secretion due to autoimmune deficiency of pancreaticβ-cells.Protecting pancreatic islets and enhancing insulin secretion has been therapeutic approaches.Mannogalactoglucan... Type 1 diabetes mellitus(T1DM) lacks insulin secretion due to autoimmune deficiency of pancreaticβ-cells.Protecting pancreatic islets and enhancing insulin secretion has been therapeutic approaches.Mannogalactoglucan is the main type of polysaccharide from natural mushroom,which has potential medicinal prospects.Nevertheless,the antidiabetic property of mannogalactoglucan in T1DM has not been fully elucidated.In this study,we obtained the neutral fraction of alkali-soluble Armillaria mellea polysaccharide(AAMP-N) with the structure of mannogalactoglucan from the fruiting body of A.mellea and investigated the potential therapeutic value of AAMP-N in T1DM.We demonstrated that AAMP-N lowered blood glucose and improved diabetes symptoms in T1DM mice.AAMP-N activated unfolded protein response(UPR) signaling pathway to maintain ER protein folding homeostasis and promote insulin secretion in vivo.Besides that,AAMP-N promoted insulin synthesis via upregulating the expression of transcription factors,increased Ca^(2+) signals to stimulate intracellular insulin secretory vesicle transport via activating calcium/calmodulin-dependent kinase Ⅱ(CamkⅡ) and cAMP/PKA signals,and enhanced insulin secretory vesicle fusion with the plasma membrane via vesicle-associated membrane protein 2(VAMP2).Collectively,these studies demonstrated that the therapeutic potential of AAMP-N on pancreatic islets function,indicating that mannogalactoglucan could be natural nutraceutical used for the treatment of T1DM. 展开更多
关键词 Mannogalactoglucan MUSHROOM Pancreatic islets Insulin secretion Insulin synthesis Unfolded protein response(UPR) Type 1 diabetes mellitus(T1DM)
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Neomicrocoleus gen.nov.(Microcoleaceae,Oscillatoriales),a novel cyanobacterial genus from benthic mats in a water channel
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作者 Ruozhen GENG Zhongshi HE +6 位作者 Kaihui GAO Peng XIAO He ZHANG si chen Hua LI Gongliang YU Renhui LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期263-276,共14页
A new filamentous cyanobacterial strain(CHAB 4127)was successfully isolated from the algal mat during the field investigation of the open channel from Luanhe River to Tianjin,China.The polyphasic approach combining mo... A new filamentous cyanobacterial strain(CHAB 4127)was successfully isolated from the algal mat during the field investigation of the open channel from Luanhe River to Tianjin,China.The polyphasic approach combining morphological,ultrastructural,ecological,and molecular features was used to characterize this studied strain.The strain is morphologically similar to the Microcoleus-like cyanobacterial taxa under light microscopy,and the radial arrangement of thylakoids is also consistent with that of Microcoleus-like groups.The phylogenetic position of CHAB 4127 based on 16S rRNA gene sequences,is shown to be clearly clustered into an independent clade with the newly established genus Microcoleusiopsis.The maximum similarity of 16S r RNA gene of the studied strain with other existing related cyanobacterial taxa is 93.97%,and the ITS secondary structures is also obviously different from other members of Microcoleaceae.Based on all the above evidence,we proposed the establishment of this novel cyanobacterial genus as Neomicrocoleus,with its type species,Neomicrocoleus tianjinensis. 展开更多
关键词 Neomicrocoleus tianjinensis morphology 16S rRNA TAXONOMY polyphasic approach
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Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE
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作者 Yong-Fang Liu Rui-Ping Wang +6 位作者 Jin Tong Bo Zhang si chen Qi-Bing Yuan Hai-Xiao Deng Ming Gu Bo Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期20-31,共12页
The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three... The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch mode.The kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn coil.The full magnetic field strength was 0.005 T.This paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker magnets.The relevant experimental results are also presented.The pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 MHz.The developed kicker satisfies the requirements for the SHINE project.Finally,numerous recommendations for the future optimization of kicker magnets are provided. 展开更多
关键词 X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites
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Development of RPA-Cas12a-fluorescence assay for rapid and reliable detection of human bocavirus 1
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作者 Weidong Qian Xuefei Wang +4 位作者 Ting Wang Jie Huang Qian Zhang Yongdong Li si chen 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第2期179-188,共10页
Human bocavirus(HBoV)1 is considered an important pathogen that mainly affects infants aged 6–24 months,but preventing viral transmission in resource-limited regions through rapid and affordable on-site diagnosis of ... Human bocavirus(HBoV)1 is considered an important pathogen that mainly affects infants aged 6–24 months,but preventing viral transmission in resource-limited regions through rapid and affordable on-site diagnosis of individuals with early infection of HBoV1 remains somewhat challenging.Herein,we present a novel faster,lower cost,reliable method for the detection of HBoV1,which integrates a recombinase polymerase amplification(RPA)assay with the CRISPR/Cas12a system,designated the RPA-Cas12a-fluorescence assay.The RPA-Cas12a-fluorescence system can specifically detect target gene levels as low as 0.5 copies of HBoV1 plasmid DNA per microliter within 40 min at 37℃without the need for sophisticated instruments.The method also demonstrates excellent specificity without cross-reactivity to non-target pathogens.Furthermore,the method was appraised using 28 clinical samples,and displayed high accuracy with positive and negative predictive agreement of 90.9%and 100%,respectively.Therefore,our proposed rapid and sensitive HBoV1 detection method,the RPA-Cas12a-fluorescence assay,shows promising potential for early on-site diagnosis of HBoV1 infection in the fields of public health and health care.The established RPA-Cas12a-fluorescence assay is rapid and reliable method for human bocavirus 1 detection.The RPA-Cas12a-fluorescence assay can be completed within 40 min with robust specificity and sensitivity of 0.5 copies/μl. 展开更多
关键词 CRISPR-Cas12a DETECTION human bocavirus 1 on-site diagnosis recombinase polymerase amplification
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Extreme value theory applied to the auroral electrojet indices
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作者 si chen Hong Yuan +2 位作者 Yong Wei Guang Yang FengZheng Yu 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期375-381,共7页
The study of extreme weather and space events has gained paramount importance in modern society owing to rapid advances in high technology.Understanding and describing exceptional occurrences plays a crucial role in m... The study of extreme weather and space events has gained paramount importance in modern society owing to rapid advances in high technology.Understanding and describing exceptional occurrences plays a crucial role in making decisive assessments of their potential impact on technical,economic,and social aspects in various fields.This research focuses on analyzing the hourly values of the auroral electrojet(AE)geomagnetic index from 1957 to 2019 by using the peak over threshold method in extreme value theory.By fitting the generalized Pareto distribution to extreme AE values,shape parameter indices were derived,revealing negative values that establish an upper bound for this time series.Consequently,it became evident that the AE values had reached a plateau,suggesting that extreme events exceeding the established upper limit are rare.As a result,although the need for diligent precautions to mitigate the consequences of such extreme events persists,surpassing the upper limit of AE values becomes increasingly challenging.It is also possible to observe an aurora in the middle-and low-latitude regions during the maximum period of the AE index. 展开更多
关键词 auroral electrojet indices extreme value theory extreme events
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Deblurring,artifact-free optical coherence tomography with deconvolution-random phase modulation
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作者 Xin Ge si chen +4 位作者 Kan Lin Guangming Ni En Bo Lulu Wang Linbo Liu 《Opto-Electronic Science》 2024年第1期13-24,共12页
Deconvolution is a commonly employed technique for enhancing image quality in optical imaging methods.Unfortu-nately,its application in optical coherence tomography(OCT)is often hindered by sensitivity to noise,which ... Deconvolution is a commonly employed technique for enhancing image quality in optical imaging methods.Unfortu-nately,its application in optical coherence tomography(OCT)is often hindered by sensitivity to noise,which leads to ad-ditive ringing artifacts.These artifacts considerably degrade the quality of deconvolved images,thereby limiting its effect-iveness in OCT imaging.In this study,we propose a framework that integrates numerical random phase masks into the deconvolution process,effectively eliminating these artifacts and enhancing image clarity.The optimized joint operation of an iterative Richardson-Lucy deconvolution and numerical synthesis of random phase masks(RPM),termed as De-conv-RPM,enables a 2.5-fold reduction in full width at half-maximum(FWHM).We demonstrate that the Deconv-RPM method significantly enhances image clarity,allowing for the discernment of previously unresolved cellular-level details in nonkeratinized epithelial cells ex vivo and moving blood cells in vivo. 展开更多
关键词 DECONVOLUTION random phase masks DEBLURRING
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Future Precipitation Extremes in China under Climate Change and Their Physical Quantification Based on a Regional Climate Model and CMIP5 Model Simulations 被引量:8
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作者 Peihua QIN Zhenghui XIE +2 位作者 Jing ZOU Shuang LIU si chen 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第3期460-479,共20页
The atmospheric water holding capacity will increase with temperature according to Clausius-Clapeyron scaling and affects precipitation.The rates of change in future precipitation extremes are quantified with changes ... The atmospheric water holding capacity will increase with temperature according to Clausius-Clapeyron scaling and affects precipitation.The rates of change in future precipitation extremes are quantified with changes in surface air temperature.Precipitation extremes in China are determined for the 21st century in six simulations using a regional climate model,RegCM4,and 17 global climate models that participated in CMIP5.First,we assess the performance of the CMIP5 models and RCM runs in their simulation of extreme precipitation for the current period(RF:1982-2001).The CMIP5 models and RCM results can capture the spatial variations of precipitation extremes,as well as those based on observations:OBS and XPP.Precipitation extremes over four subregions in China are predicted to increase in the mid-future(MF:2039-58)and far-future(FF:2079-98)relative to those for the RF period based on both the CMIP5 ensemble mean and RCM ensemble mean.The secular trends in the extremes of the CMIP5 models are predicted to increase from 2008 to 2058,and the RCM results show higher interannual variability relative to that of the CMIP5 models.Then,we quantify the increasing rates of change in precipitation extremes in the MF and FF periods in the subregions of China with the changes in surface air temperature.Finally,based on the water vapor equation,changes in precipitation extremes in China for the MF and FF periods are found to correlate positively with changes in the atmospheric vertical wind multiplied by changes in surface specific humidity(significant at the p<0.1 level). 展开更多
关键词 precipitation extremes regional climate model CMIP5 models
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Role of TGF-βl Signaling in Heart Valve Calcification Induced by Abnormal Mechanical Stimulation in a Tissue Engineering Model 被引量:3
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作者 Xing-jian HU Wen-cong-hui WU +5 位作者 Nian-guo DONG Jia-wei SHI Jun-wei LIU si chen chen DENG Feng SHI 《Current Medical Science》 SCIE CAS 2018年第5期765-775,共11页
A tissue engineering model of heart valve calcification induced in a bio-reactor was established to evaluate the calcification induced by abnormal mechanical stimulation and explore the underlying molecular mechanisms... A tissue engineering model of heart valve calcification induced in a bio-reactor was established to evaluate the calcification induced by abnormal mechanical stimulation and explore the underlying molecular mechanisms.Polyethylene glycol (PEG)-modified decellularized porcine aortic leaflets seeded with human valve interstitial cells (huVICs)were mounted on a Ti-Ni alloy frame to fabricate two-leaflet and three-leaflet tissue engineered valves.The two-leaflet model valves were exposed to abnormal pulsatile flow stimulation with null (group A),low (1000mL/min,group B),medium (2000mL/min,group C),and high velocity (3000mL/min,group D)for 14 days. Morphology and calcification were assessed by yon Kossa staining,alkaline phosphatase (ALP)content,and Runx2 immunostaining.Leaflet calcification and mRNA and protein expression of transforming growth factor (TGF)-β1,bone morphogenetic protein 2 (BMP2),Smadl,and MSX2 were measured at different time points.ALP content was examined in two-leaflet valves seeded with BMP2 shRNA plasmid-infected huVICs and exposed to the same stimulation conditions.The results showed that during 14 days of flow stimulation,huVICs on the leaflet surface proliferated to generate normal monolayer coverage in groups A,B,and C.Under mechanical stimulation,huVICs showed a parallel growth pattern in the direction of the fluid flow,but huVICs exhibited disordered growth in the high-velocity flow environment,yon Kossa staining,ALP measurement,and immunohistochemical staining for Runx2 confirmed the lack of obvious calcification in group A and significant calcification in group D.Expression levels of TGF-β1,BMP2, and MSX2 mRNA and protein were increased under fluid stimulation.ALP production by BMP2 shRNA plasmid-infected huVICs on model leaflets was significantly reduced.In conclusion,abnormal mechanical stimulation in a bioreactor induced calcification in the tissue engineering valve model.The extent of calcification correlated positively with the flow velocity,as did the mRNA and protein levels of TGF-β1,BMP2,and MSX2.These findings indicate that TGF-β1/BMP2 signaling is involved in valve calcification induced bv abnormal mechanical stimulation. 展开更多
关键词 VALVE CALCIFICATION ABNORMAL mechanical STIMULATION BIOREACTOR TGF-β1 signal pathway
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Dye-sensitized Solar Cells with Higher J_(sc) by Using Polyvinylidene Fluoride Membrane Counter Electrodes 被引量:3
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作者 Xiaodong Li Dingwen Zhang +4 位作者 si chen Heng Zhang Zhuo Sun Sumei Huang Xijiang Yin 《Nano-Micro Letters》 SCIE EI CAS 2011年第3期195-199,共5页
A flexible counter electrode(CE) for dye-sensitized solar cells(DSCs) has been fabricated using a micro-porous polyvinylidene fluoride membrane as support media and sputtered Pt as the catalytic material.Non-conventio... A flexible counter electrode(CE) for dye-sensitized solar cells(DSCs) has been fabricated using a micro-porous polyvinylidene fluoride membrane as support media and sputtered Pt as the catalytic material.Non-conventional structure DSCs have been developed by the fabricated CEs. The Pt metal was sputtered onto one surface of the membrane as the catalytic material. DSCs were assembled by attaching the Ti O2 electrode to the membrane surface without Pt coating. The membrane was with cylindrical pore geometry. It served not only as a substrate for the CE but also as a spacer for the DSC. The fabricated DSC with the flexible membrane CE showed higher photocurrent density than the conventional sandwich devices based on chemically deposited Pt/FTO glass, achieving a photovoltaic conversion efficiency of 4.43%. The results provides useful information in investigation and development of stable, low-cost, simple-design, flexible and lightweight DSCs. 展开更多
关键词 Polyvinylidene fluoride Counter electrode FLEXIBLE Dye-sensitized solar cell
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Anti-EpCAM functionalized graphene oxide vector for tumor targeted siRNA delivery and cancer therapy 被引量:2
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作者 si chen Shuang Zhang +3 位作者 Yifan Wang Xin Yang Hong Yang Chunying Cui 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第5期598-611,共14页
Graphene oxide(GO) has emerged as a potential drug delivery vector. For siRNA delivery, GO should be modified to endow it with gene delivery ability and targeting effect. However, the cationic materials used previousl... Graphene oxide(GO) has emerged as a potential drug delivery vector. For siRNA delivery, GO should be modified to endow it with gene delivery ability and targeting effect. However, the cationic materials used previously usually had greater toxicity. In this study, GO was modified with a non-toxicity cationic material(chitosan) and a tumor specific monoclonal antibody(anti-EpCAM) for the delivery of survivin-siRNA(GCE/siRNA). And the vector(GCE) prepared was proved with excellent biosafety and tumor targeting effect. The GCE exhibited superior performance in loading si RNA, maintained stability in different solutions and showed excellent protection effect for survivin-siRNA in vitro. The gene silencing results in vitro showed that the m RNA level and protein level were down-regulated by 48.24% ± 2.50% and 44.12% ± 3.03%, respectively, which was equal with positive control( P > 0.05). It was also demonstrated that GCE/siRNA had a strong antitumor effect in vitro, which was attributed to the efficient antiproliferation, and migration and invasion inhibition effect of GCE/siRNA. The results in vivo indicated that GCE could accumulate siRNA in tumor tissues. The tumor inhibition rate of GCE/siRNA 54.74% ± 5.51% was significantly higher than control 4.87% ±8.49%. Moreover, GCE/siRNA showed no toxicity for blood and main organs, suggesting that it is a biosafety carrier for gene delivery. Taken together, this study provides a novel design strategy for gene delivery system and siRNA formulation. 展开更多
关键词 Graphene oxide siRNA delivery Survivin Anti-EpCAM Gene silencing
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