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Tea polyphenols and their chemopreventive and therapeutic effects on colorectal cancer 预览
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作者 Shi-Tong Wang Wen-Qi Cui +3 位作者 Dan Pan Min Jiang Bing Chang Li-Xuan Sang 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第6期562-597,共36页
Colorectal cancer(CRC),a multifactorial disease,is usually induced and developed through complex mechanisms,including impact of diet and lifestyle,genomic abnormalities,change of signaling pathways,inflammatory respon... Colorectal cancer(CRC),a multifactorial disease,is usually induced and developed through complex mechanisms,including impact of diet and lifestyle,genomic abnormalities,change of signaling pathways,inflammatory response,oxidation stress,dysbiosis,and so on.As natural polyphenolic phytochemicals that exist primarily in tea,tea polyphenols(TPs)have been shown to have many clinical applications,especially as anticancer agents.Most animal studies and epidemiological studies have demonstrated that TPs can prevent and treat CRC.TPs can inhibit the growth and metastasis of CRC by exerting the antiinflammatory,anti-oxidative or pro-oxidative,and pro-apoptotic effects,which are achieved by modulations at multiple levels.Many experiments have demonstrated that TPs can modulate several signaling pathways in cancer cells,including the mitogen-activated protein kinase pathway,phosphatidylinositol-3 kinase/Akt pathway,Wnt/β-catenin pathway,and 67 kDa laminin receptor pathway,to inhibit proliferation and promote cell apoptosis.In addition,novel studies have also suggested that TPs can prevent the growth and metastasis of CRC by modulating the composition of gut microbiota to improve immune system and decrease inflammatory responses.Molecular pathological epidemiology,a novel multidisciplinary investigation,has made great progress on CRC,and the further molecular pathological epidemiology research should be developed in the field of TPs and CRC.This review summarizes the existing in vitro and in vivo animal and human studies and potential mechanisms to examine the effects of tea polyphenols on CRC. 展开更多
关键词 Tea polyphenols Colorectal cancer Gut microbiota Signal pathway ANTIINFLAMMATION MECHANISMS
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Bushen Kangshuai tablet inhibits progression of atherosclerosis by intervening in macrophage autophagy and polarization
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作者 Xie Yingyu Tian Lijun +5 位作者 Fang Zihan Zhong Aiqin Ao Zhang Xu Shixin Wang Yanan Zhang Junping 《中医杂志:英文版》 SCIE CAS CSCD 2020年第1期28-37,共10页
OBJECTIVE:To investigate the efficacy of Bushen Kangshuai(BS-KS)tablet on autophagy and polarization in mouse macrophage RAW 264.7.MEYHODS:Macrophage autophagy was induced by oxidized low-density lipoprotein(100μg/m ... OBJECTIVE:To investigate the efficacy of Bushen Kangshuai(BS-KS)tablet on autophagy and polarization in mouse macrophage RAW 264.7.MEYHODS:Macrophage autophagy was induced by oxidized low-density lipoprotein(100μg/m L).To detect the levels of autophagy,macrophage were transfected with double fluorescence LC3 autophagy adenovirus,then the numbers of autophagosomes and autophagic lysosomes were asessed by confocal microscopy.The autophagy related proteins expression of PI3 K,Akt,phospho-m Akt(p-Akt)and m TOR,phospho-m TOR(p-TOR),p62,microtubule-associated protein 1(LC3-Ⅱ)were determined by western blotting.The macrophage polarization model was induced by lipopolysaccharide(1μg/m L).The m RNA levels of i NOS,CD86(M1 macrophages marker molecules),and CD206,Arg-1(M2 macrophages marker molecules)were detected by real-time quantitative PCR.The concentration of cytokines TNF-αand IL-10 was determined by enzyme-linked immunosorbent assay.The protein expression of nuclear proteins PPAR-γ,NF-κB,and cytoplasmic protein IKBαwas determined by western blotting.RESULTS:The expression of the autophagy-related protein LC3-Ⅱwas increased and the expression of p62 was decreased in the BS-KS intervention group.The protein expression of PI3 K,p-Akt,and p-m TOR was also reduced.BS-KS also inhibited the m RNA expression of i NOS and CD86 on M2 macrophage,but promoted the expression of CD206 and Arg-1 on M2 macrophage.With respect to the regulation of inflammatory factors,BS-KS could inhibit the secretion of pro-inflammatory TNF-αand promote the secretion of anti-inflammatory IL-10.It also inhibited the protein expression of IKB-αand NF-κB,and promoted the expression of nuclear protein PPAR-γ.CONCLUSION:We believe that BS-KS promotes macrophage autophagy by increasing the level of autophagy protein and inhibiting the PI3 K/Akt/m TOR signaling pathway.Furthermore,BS-KS seems to inhibit macrophage M1 polarization and promote M2 polarization via the PPAR gamma/NF-κB signaling pathway,thus playing an inhibitory role in atheros 展开更多
关键词 ATHEROSCLEROSIS Macrophages AUTOPHAGY Lipoproteins LDL LIPOPOLYSACCHARIDES Signal TRANSDUCTION Bushen Kangshuai tablets
Danshensu Ameliorates Cardiac Ischaemia Reperfusion Injury through Activating Sirt1/Fox01/Rab7 Signal Pathway
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作者 SUN Da-wei GAO Qing QI Xin 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2020年第4期283-291,共9页
Objective:To explore the specific molecular mechanisms of Danshensu(DSS)in the treatment of ischemia reperfusion injury(IRI).Methods:IRI model was established with isolated rat hearts by performing global ischaemia fo... Objective:To explore the specific molecular mechanisms of Danshensu(DSS)in the treatment of ischemia reperfusion injury(IRI).Methods:IRI model was established with isolated rat hearts by performing global ischaemia for 30 min,and then followed by 60 min reperfusion.Also,H9C2 cells were subjected to 4-h hypoxia followed by 3-h reoxygenation.Then 10|i mol/L DSS were added in the reperfusion/reoxygenation step to intervene IRI.Cardiac function,structural change and apoptosis were respectively tested by Langendorff System,hematoxylin and eosin(HE)and terminal-deoxynucleotidyl transferase mediated nick endabeling(TUNEL)stainings.Then lactate dehydrogenase(LDH),cardiac troponin T(cTnT),reactive oxygen species(ROS),superoxide dismutase(SOD)and glutathione peroxidase(GSH-PX)were detected by enzyme-linked immunosorbent assay(ELISA).Sirt1/FoxO1/Rab7 Signal Pathway was monitored at both protein and mRNA levels.Results:The results showed that IRI not only greatly attenuated cardiac function(LVDP and±dp/dtmax,P<0.01,P<0.05)and increased the level of the marker enzymes(cTnT,LDH,P<0.01)from the coronary effluents,but also markedly induced changes in the structure of cardiomyocytes and contributed to apoptosis,which were mediated by boosted en doge nous ROS.However,after treatment with DSS all above indexes were improved,which was related to activating Sirt1/FoxO1/Rab7 signal pathway accompanied with the enhancement of antioxidant defense system,such as SOD and GSH-PX.Conclusion:DSS is able to protect hearts from IRI,which may be attributable to inhibiting excessive ROS through Sirt1/FoxO1/Rab7 signaling. 展开更多
关键词 Chinese medicine DANSHENSU ischemia reperfusion injury Sirt1/FoxO1/Rab7 signal pathway reactive oxygen species apoptosis
Signal perception during plant-bacteria interactions: from chemicals to physical signals
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作者 Bao-Zhen Ren Wei Qian 《中国科学:生命科学英文版》 SCIE CAS CSCD 2020年第2期305-307,共3页
During interactions between host plants and microbes, discrimination between "self" and "nonself" is at the center of many biological relationships and determines the success of infection by microb... During interactions between host plants and microbes, discrimination between "self" and "nonself" is at the center of many biological relationships and determines the success of infection by microbial pathogens or immunity of the hosts. 展开更多
关键词 Signal IMMUNITY SIGNALS
Testis of Male Tilapia Under Methomyl Stress: Transcriptome Changes and Signal Pathway Analysis 预览
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作者 Shunlong MENG Tao LIU +2 位作者 Chao SONG Cong ZHANG Jiazhang CHEN 《农业生物技术:英文版》 CAS 2020年第2期5-9,15,共6页
This study was conducted to find the differentially expressed genes and understand the transcriptome change characteristics in the testis of tilapia(Oreochromis niloticus) stressed by methomyl.The tilapia were exposed... This study was conducted to find the differentially expressed genes and understand the transcriptome change characteristics in the testis of tilapia(Oreochromis niloticus) stressed by methomyl.The tilapia were exposed to 200 μg/L methomyl for 30 d,and then the testis samples were collected and used for the highthroughput sequencing.The results showed that 369 significant differentially expressed genes were obtained,including 160 significantly down-regulated genes,and209 significantly up-regulated genes.The enrichment of the differentially expressed genes in ECM-receptor interaction signaling pathway and MAPK signaling pathway was obvious.The adhesion of testis tissue cells was influenced by methomyl stress,which induced the expression of related gene in ECM-receptor interaction up-regulating,such as laminins,integrin α6 and integrin β1,in order to stabilize testis tissue structure.JNK,MAP3 K and MKK4 in the JNK pathway were significantly up-regulated,which enhanced transcription factor AP-1 to promote the expression of P53,Bax and other pro-apoptotic proteins.The expression of growth-related factors in the ERK pathway of MAPK signal pathway was influenced by methomyl stress.The apoptosis-related genes and pregnancy-related genes have significant differential expression under methomyl stress,and thereby,the proliferation of reproduction cells in the testis tissue may be affected. 展开更多
关键词 METHOMYL TILAPIA TESTIS TRANSCRIPTOME Signal pathway
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自动开机电路的设计与优化 预览
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作者 程传阳 王振发 《工业控制计算机》 2020年第2期70-71,共2页
现今,开机电路大都使用的是手动按键进行开机,这种开机方式不仅相对复杂,而且可靠性相对较低。研究了一种安全、可靠的通过自动开机脉冲信号控制的开机电路,通过该自动脉冲信号实现开机,节省了手动开机的时间且更加便捷,经验证,开机电... 现今,开机电路大都使用的是手动按键进行开机,这种开机方式不仅相对复杂,而且可靠性相对较低。研究了一种安全、可靠的通过自动开机脉冲信号控制的开机电路,通过该自动脉冲信号实现开机,节省了手动开机的时间且更加便捷,经验证,开机电路较现有开机电路,更加简单、安全、可靠。因而,较现有的开机电路,该开机电路的应用场景也将更加广泛,行业认可度也将更高。 展开更多
关键词 开机 脉冲 信号 电路
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一种绞车保护系统结构及软件的设计 预览
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作者 胡爱保 《机械管理开发》 2020年第3期177-178,185,共3页
针对煤炭开采斜巷运输系统中存在的一些问题,对煤矿斜巷运输系统进行分析,结合现场工作,开发出一种新型的斜巷绞车保护软件。该软件实现了在进行井下斜巷运输作址时车房和井口信号的一致性,提高了煤炭运输效率和生产工作安全性。
关键词 斜巷 绞车 信号 单片机
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Extraction of a target in sea clutter via signal decomposition
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作者 Zhiyu SHAO Jiangheng HE Shunshan FENG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2020年第2期230-232,共3页
Dear editor,Target detection at the sea surface is crucial for the ensuring the security of drilling platforms,ships,ports,etc.However,the presence of sea clutter poses a challenge to radar detection.Since the sea sur... Dear editor,Target detection at the sea surface is crucial for the ensuring the security of drilling platforms,ships,ports,etc.However,the presence of sea clutter poses a challenge to radar detection.Since the sea surface is a dynamic surface,its scattering properties are extremely complex.For a highresolution radar working at a low grazing angle. 展开更多
关键词 DOPPLER EXTRACTION of a TARGET in sea CLUTTER VIA signal DECOMPOSITION
Eigenvalue spectrum analysis for temporal signals of Kerr optical frequency combs based on nonlinear Fourier transform
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作者 王佳 盛爱国 +2 位作者 黄鑫 李荣玉 何广强 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第3期225-231,共7页
Based on the nonlinear Schr?dinger equation(NLSE) with damping, detuning, and driving terms describing the evolution of signals in a Kerr microresonator, we apply periodic nonlinear Fourier transform(NFT) to the study... Based on the nonlinear Schr?dinger equation(NLSE) with damping, detuning, and driving terms describing the evolution of signals in a Kerr microresonator, we apply periodic nonlinear Fourier transform(NFT) to the study of signals during the generation of the Kerr optical frequency combs(OFCs). We find that the signals in different states, including the Turing pattern, the chaos, the single soliton state, and the multi-solitons state, can be distinguished according to different distributions of the eigenvalue spectrum. Specially, the eigenvalue spectrum of the single soliton pulse is composed of a pair of conjugate symmetric discrete eigenvalues and the quasi-continuous eigenvalue spectrum with eye-like structure.Moreover, we have successfully demonstrated that the number of discrete eigenvalue pairs in the eigenvalue spectrum corresponds to the number of solitons formed in a round-trip time inside the Kerr microresonator. This work shows that some characteristics of the time-domain signal can be well reflected in the nonlinear domain. 展开更多
关键词 nonlinear Fourier transform Kerr optical frequency combs nonlinear signal processing
Spectral-spatial Classification of Hyperspectral Images Using Signal Subspace Identification and Edge-preserving Filter
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作者 Negin Alborzi Fereshteh Poorahangaryan Homayoun Beheshti 《国际自动化与计算杂志:英文版》 EI CSCD 2020年第2期222-232,共11页
Hyperspectral images in remote sensing include hundreds of spectral bands that provide valuable information for accurately identify objects.In this paper,a new method of classifying hyperspectral images using spectral... Hyperspectral images in remote sensing include hundreds of spectral bands that provide valuable information for accurately identify objects.In this paper,a new method of classifying hyperspectral images using spectral spatial information has been presented.Here,using the hyperspectral signal subspace identification(HYSIME)method which estimates the signal and noise correlation matrix and selects a subset of eigenvalues for the best representation of the signal subspace in order to minimize the mean square error,subsets from the main sample space have been extracted.After subspace extraction with the help of the HYSIME method,the edge-preserving filtering(EPF),and classification of the hyperspectral subspace using a support vector machine(SVM),results were then merged into the decision-making level using majority rule to create the spectral-spatial classifier.The simulation results showed that the spectral-spatial classifier presented leads to significant improvement in the accuracy and validity of the classification of Indiana,Pavia and Salinas hyperspectral images,such that it can classify these images with 98.79%,98.88% and 97.31% accuracy,respectively. 展开更多
关键词 Hyperspectral image remote sensing the hyperspectral signal subspace identification(HYSIME) edge-preserving filter CLASSIFICATION support vector machine
信号电缆备用贯通芯线间增加整流元件的探讨 预览
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作者 欧阳征 《铁路通信信号工程技术》 2020年第3期105-108,共4页
为确保信号电缆备用贯通芯线的良好,在应急处置中发挥作用,不仅要测试贯通芯线间的电阻值,还需在最远端方向电缆盒内人工断开芯线连接,定期测试备用贯通芯线线间综合绝缘电阻值。其测试工作劳动强度大、次生风险高,为提高安全检测效率,... 为确保信号电缆备用贯通芯线的良好,在应急处置中发挥作用,不仅要测试贯通芯线间的电阻值,还需在最远端方向电缆盒内人工断开芯线连接,定期测试备用贯通芯线线间综合绝缘电阻值。其测试工作劳动强度大、次生风险高,为提高安全检测效率,经模拟信号电缆备用贯通芯线4种绝缘不良的场景,使用实物测试方法,验证了在信号电缆贯通芯线最末端方向电缆盒贯通芯线连接处增加一个整流元件,可以完成对贯通芯线的三测试(芯线间电阻、芯线间综合绝缘电阻、芯线对地综合绝缘电阻测试),根据测试数据可以有效判断存在问题的芯线。 展开更多
关键词 信号 贯通芯线 整流元件 测试
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Fluorescence Signal Amplification Strategies Based on DNA Nanotechnology for miRNA Detection
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作者 LI Tao DUAN Ruilin +2 位作者 DU AN Zhijuan HUANG Fujian XIA Fan 《高等学校化学研究:英文版》 SCIE CAS CSCD 2020年第2期194-202,共9页
In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principle... In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principles of amplification strategies are explained,including rolling circle amplification(RCA),catalytic hairpin assembly(CHA),hybridization chain reaction(HCR)and DNA walker.Subsequently,the application of these signal amplifica­tion methods in biosensing and bioimaging are covered and described.Finally,the challenges and the outlook of fluorescence signal amplification methods for miRNA detection are briefly commented. 展开更多
关键词 Signal amplification DNA nanotechnology FLUORESCENCE miRNA detection Biosensing and bioimaging
植物谷胱甘肽应答非生物胁迫的分子机制
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作者 韩键 白云赫 +4 位作者 朱旭东 郑婷 张克坤 王晨 房经贵 《分子植物育种》 CAS CSCD 北大核心 2020年第5期1672-1680,共9页
谷胱甘肽(GSH)是一种普遍存在于植物中的抗氧化剂,在维持组织抗氧化防御和调节氧化还原敏感信号转导中起着关键作用。深入研究GSH在非生物胁迫中的作用,对从分子水平揭示植物GSH积累的调控机制具有重要意义。本研究从植物GSH代谢途径及... 谷胱甘肽(GSH)是一种普遍存在于植物中的抗氧化剂,在维持组织抗氧化防御和调节氧化还原敏感信号转导中起着关键作用。深入研究GSH在非生物胁迫中的作用,对从分子水平揭示植物GSH积累的调控机制具有重要意义。本研究从植物GSH代谢途径及其相关酶、GSH在植物应激反应中的调节、GSH参与植物激素代谢等方面进行综述,并对谷胱甘肽在植物生长发育、与其它信号通路间交互作用的研究前景进行展望,以期为植物谷胱甘肽代谢以及其在非生物胁迫方面的研究提供一定的理论参考。 展开更多
关键词 胁迫响应 谷胱甘肽 调节作用 ROS 信号
MiR-430 Can Affect the Mesoderm Formation and Metamorphosis of Paralichthys olivaceus by Targeting lefty Gene 预览
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作者 LI Rui WANG Zhenwei +3 位作者 SUN Minmin PENG Meiting QI Jie WANG Zhigang 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2020年第2期409-416,共8页
MiR-430 is a non-coding small RNA that participates in early embryonic development by acting on the Nodal signaling pathway.Its functions in Paralichthys olivaceus(P.olivaceus),however,remain unclear.In this study,thr... MiR-430 is a non-coding small RNA that participates in early embryonic development by acting on the Nodal signaling pathway.Its functions in Paralichthys olivaceus(P.olivaceus),however,remain unclear.In this study,through biological information technology,we hypothesized lefty was the target gene of miR-430.Lefty is a divergent member of the transforming growth factor-β(TGF-β)superfamily,and is involved in regulating left-right patterning as an antagonist of the Nodal signaling pathway.To study the relationship between miR-430 and lefty gene,miR-430 and fluorescent expression vector were transfected into embryo cells.Our results showed that miR-430 has important effects on early embryonic development.It can inhibit the expressions of lefty and other genes related to Nodal signaling pathway.Additionally,the expression of miR-430 was involved in the metamorphosis of P.olivaceus.This study clarifies the function of miR-430 in P.olivaceus,which will be helpful for further research on the interactions between miR-430 and the Nodal signaling pathway. 展开更多
关键词 miR-430 LEFTY Nodal signal pathway Paralichthys olivaceus
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Comparative phylogeography of two sister species of snowcock: impacts of species-specific altitude preference and life history 预览
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作者 Bei An Lixun Zhang +1 位作者 Yutao Wang Sen Song 《鸟类学研究:英文版》 CSCD 2020年第1期45-56,共12页
Background: Phylogeographical patterns and population dynamics are usually interpreted by environmental disturbances and geographic barriers of the past. However, sister species may exhibit disparate patterns of genet... Background: Phylogeographical patterns and population dynamics are usually interpreted by environmental disturbances and geographic barriers of the past. However, sister species may exhibit disparate patterns of genetic structures and population dynamics due to their habitat preference and altitude segregation. In this study, we tested how species-specific altitude habitat affected phylogeographical patterns in two sister snowcock species, Tibetan(Tetraogallus tibetanus) and Himalayan Snowcocks(T. himalayensis).Methods: A panel of seven microsatellite loci and a fragment of Mitochondrial DNA Control Region were used to investigate genetic structures and population dynamics in hope of revealing the underlying evolutionary processes through the identification of possible past demographic events.Results: Our results suggest that T. himalayensis showed a significant phylogeographical signal in mtDNA(FST microsatellite(F the glacial-interglacial cycles in the = 0.66, p < 0.001) and ST Pleistocene and followed demog= 0.11, p < 0.001) data and is stable duringraphic contraction until 0.003 million years(Mys) ago. The phylogeographical signal of T. tibetanus is lower than the level of genetic difference among populations in mtDNA(FST icrosatellite(F= 0.41, p < 0.001) and mST s been experien= 0.09, p < 0.001) data, likely benefiting from stable habitats over a long period of time. T. tibetanus hacing expansion since 0.09 Mys ago. However, an abnormally haplotype H9 from T. himalayensis clustering with T. tibetanus was spotted.Conclusion: Our results indicate that differences in habitat preference and altitude specialities were reflected in the genetic structure patterns and population dynamics of these two species. These dissimilarities in life history traits might have affected the dispersal and survival abilities of these two species differently during environmental fluctuations. The results of this study also enriched our knowledge on population differentiation and connectivity in high altitude mountain ecosystems. 展开更多
关键词 Himalayan Snowcock Phylogeographical pattern Phylogeographical signal Population dynamics Tetraogallus himalayensis Tetraogallus tibetanus Tibetan Snowcock
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Cascaded DNA circuits-programmed self-assembly of spherical nucleic acids for high signal amplification
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作者 Xiang Li Dongbao Yao +5 位作者 Junxiang Zhou Xiang Zhou Xianbao Sun Bing Wei Chengxu Li Bin Zheng 《中国科学:化学英文版》 SCIE EI CAS CSCD 2020年第1期92-98,共7页
Signal amplification is an important issue in DNA nanotechnology and molecular diagnostics.In this work,we report a strategy for the catalytic self-assembly of spherical nucleic acids(SNAs)programmed by two-layer casc... Signal amplification is an important issue in DNA nanotechnology and molecular diagnostics.In this work,we report a strategy for the catalytic self-assembly of spherical nucleic acids(SNAs)programmed by two-layer cascaded DNA circuits through integrating an entropy-driven catalytic network,a catalytic hairpin assembly circuit,and a facile SNA assembly-based reporter system.This integrated system could implement~100,000-fold signal amplification in the presence of 1 pM of input target.Possessing powerful amplification ability of nucleic acid signal,our strategy should be of great potential in fabricating more robust dynamic networks to be applied for signal transduction,DNA computing,and nucleic acid-based diagnostics. 展开更多
关键词 catalytic self-assembly DNA circuit signal amplification spherical nucleic acids
Advanced algorithms for retrieving pileup peaks of digital alpha spectroscopy using antlions and particle swarm optimizations 预览
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作者 Mohamed S.El_Tokhy 《核技术:英文版》 SCIE CAS CSCD 2020年第4期47-68,共22页
Optimization algorithms are applied to resolve the second-order pileup(SOP)issue from high counting rates occurring in digital alpha spectroscopy.These are antlion optimizer(ALO)and particle swarm optimization(PSO)alg... Optimization algorithms are applied to resolve the second-order pileup(SOP)issue from high counting rates occurring in digital alpha spectroscopy.These are antlion optimizer(ALO)and particle swarm optimization(PSO)algorithms.Both optimization algorithms are coupled to one of the three proposed peak finder algorithms.Three custom time-domain algorithms are proposed for retrieving SOP peaks,namely peak seek,slope tangent,and fast array algorithms.In addition,an average combinational algorithm is applied.The time occurrence of the retrieved peaks is tested for an elimination of illusive pulses.Conventional methods are inaccurate and timeconsuming.ALO and PSO optimizations are used for the localization of retrieved peaks.Optimum cost values that achieve the best fitness values are demonstrated.Thus,the optimum positions of the detected peak heights are achieved.Evaluation metrics of the optimized algorithms and their influences on the retrieved peaks parameters are established.Comparisons among such algorithms are investigated,and the algorithms are inspected in terms of their computational time and average error.The peak seek algorithm achieves the lowest average computational error for pulse parameters(amplitude and position).However,the fast array algorithm introduces the largest average error for pulse parameters.In addition,the peak seek algorithm coupled with an ALO or PSO algorithm is observed to realize a better performance in terms of the optimum cost and computational time.By contrast,the performance of the peak seek recovery algorithm is improved using the PSO.Furthermore,the computational time of the peak optimization using the PSO is much better than that of the ALO algorithm.As a final conclusion,the accuracy of the peaks detected by the PSO surpasses that for the peaks detected by the ALO.The implemented peak retrieval algorithms are validated through a comparison with experimental results from previous studies.The proposed algorithms achieve a notable precision for compensation of the SOP peaks within 展开更多
关键词 Alpha spectrometry instrument Second-order pileup Signal processing Optimization algorithms
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Highly sensitive detection of Rydberg atoms with fluorescence loss spectrum in cold atoms
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作者 师雪荣 张好 +3 位作者 景明勇 张临杰 肖连团 贾锁堂 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第1期218-222,共5页
Fluorescence loss spectrum for detecting cold Rydberg atoms with high sensitivity has been obtained based on lock-in detection of fluorescence of 6 P3/2 state when cooling lasers of the magneto-optical trap are modula... Fluorescence loss spectrum for detecting cold Rydberg atoms with high sensitivity has been obtained based on lock-in detection of fluorescence of 6 P3/2 state when cooling lasers of the magneto-optical trap are modulated.The experiment results show that the signal to noise ratio has been improved by 32.64 dB when the modulation depth(converted to laser frequency)and frequency are optimized to 4 MHz and 6 kHz,respectively.This technique enables us to perform a highly sensitive non-destructive detection of Rydberg atoms. 展开更多
关键词 fluorescence loss spectrum Rydberg atoms signal to noise ratio
Transcriptomic analysis reveals putative osmoregulation mechanisms in the kidney of euryhaline turbot Scophthalmus maximus responded to hypo-saline seawater 预览
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作者 CUI Wenxiao MA Aijun +7 位作者 HUANG Zhihui WANG Xin’an SUN Zhibin LIU Zhifeng ZHANG Wei YANG Jingkun ZHANG Jinsheng QU Jiangbo 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2020年第2期467-479,共13页
Turbot harbor a relatively remarkable ability to adapt to opposing osmotic challenges and are an excellent model species to study the physiological adaptations of flounder associated with osmoregulatory plasticity.The... Turbot harbor a relatively remarkable ability to adapt to opposing osmotic challenges and are an excellent model species to study the physiological adaptations of flounder associated with osmoregulatory plasticity.The kidney transcriptome of turbot treated 24 h in water of hypo-salinity(salinity 5)and seawater(salinity 30)was sequenced and characterized.In silico analysis indicated that all unigenes had significant hits in seven databases.The functional annotation analysis of the transcriptome showed that the immune system and biological processes associated with digestion,absorption,and metabolism played an important role in the osmoregulation of turbot in response to hypo-salinity.Analysis of biological processes associated with inorganic channels and transporters indicated that mineral absorption and bile secretion contributed to iono-osmoregulation resulting in cell volume regulation and cell phenotypic plasticity.Moreover,we analyzed and predicted the mechanisms of canonical signaling transduction.Biological processes involved in renin secretion,ECM-receptor interaction,adherens junction,and focal adhesion played an important role in the plasticity phenotype in hypo-stress,while the signal transduction network composed of the MAPK signaling pathway and PI3K-Akt signaling pathway with GABAergic synapse,worked in hypoosmoregulation signal transduction in the turbot.In addition,analysis of the tissue specificity of targeted gene expression using qPCR during salinity stress was carried out.The results showed that the kidney,gill,and spleen were vital regulating organs of osmotic pressure,and the osmoregulation pattern of euryhaline fish dif fered among species. 展开更多
关键词 osmoregulation mechanisms Scophthalmus maximus hypo-saline signal transduction cell volume regulation gene expression
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Carrier frequency and symbol rate estimation based on cyclic spectrum 预览
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作者 CAO Sisi ZHANG Weiyan 《系统工程与电子技术:英文版》 SCIE EI CSCD 2020年第1期37-44,共8页
Carrier frequency and symbol rate estimation are the main contents of parameter estimation,which is the basis of modulation recognition and further processing of signals especially in non-cooperative communication.Wit... Carrier frequency and symbol rate estimation are the main contents of parameter estimation,which is the basis of modulation recognition and further processing of signals especially in non-cooperative communication.With the development of wireless communication,the signal transmission environment has become increasingly bad,causing more difficulties in parameter estimation.It is well known that the signal cycle spectrum is robust to noises and signal parameters are closely related.In practice,it is impossible to calculate the cyclic spectrum of infinite length data signals.When using finite length data to obtain a cycle spectrum,the truncation noise is induced,resulting in interference.It is necessary to overcome the influence of noises in order to improve the detection ability of discrete spectral lines.An improved method of the discrete spectral line extraction algorithm is proposed by reflecting the amplitude advantage of discrete spectral lines through salient features of continuous noises in discrete spectral line neighborhood. 展开更多
关键词 digital modulation signal carrier frequency symbol rate cyclic spectrum noise control
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