To effectively extract the interturn short circuit fault features of induction motor from stator current signal, a novel feature extraction method based on the bare-bones particle swarm optimization （BBPSO） algorith...To effectively extract the interturn short circuit fault features of induction motor from stator current signal, a novel feature extraction method based on the bare-bones particle swarm optimization （BBPSO） algorithm and wavelet packet was proposed. First, according to the maximum inner product between the current signal and the cosine basis functions, this method could precisely estimate the waveform parameters of the fundamental component using the powerful global search capability of the BBPSO, which can eliminate the fundamental component and not affect other harmonic components. Then, the harmonic components of residual current signal were decomposed to a series of frequency bands by wavelet packet to extract the interturn circuit fault features of the induction motor. Finally, the results of simulation and laboratory tests demonstrated the effectiveness of the proposed method.展开更多
A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magne...A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magnetic particles (MNPs) for the immobilization of linker DNA and CdS NPs and the subsequent target DNA hybridization. Using the unique characteristic of nicking endonuclease for cutting one specific strand of double strand DNA (ds DNA), the linker DNA could be transected and the target DNA could be liberated for re-hybridization and hence the amount of released CdS NPs was enhanced. Due to the advantage of the MNPs and signal amplification from the target recycling, the analyte DNA could be detected by the square-wave stripping voltammetry (SWV) in a wide linear range from 0.4 fM to 100 fM with the detection limit down to 0.08 fM. The proposed DNA detection strategy possesses high sensitivity, satisfactory reproducibility and excellent stability, which might have potential in other DNA biological assays.展开更多
For antiviral signaling mediated by retinoic acid-inducible gene I （RiG-I）-like receptors （RLRs）, the recruitment of cytosoUc RLRs and downstream molecules （such as TBK1 and IKKε） to mitochondriaL platform is a...For antiviral signaling mediated by retinoic acid-inducible gene I （RiG-I）-like receptors （RLRs）, the recruitment of cytosoUc RLRs and downstream molecules （such as TBK1 and IKKε） to mitochondriaL platform is a central event that facilitates the establishment of host antiviral state. Here, we present an example of viral targeting for immune evasion through spatial isolation of TBK1/IKKε from mitochond riai antiviral platform, which was employed by severe fever with thrombocytopenia syndrome virus （SFTSV）, a deadly bunyavirus emerging recently. We showed that SFTSV nonstructural protein NSs functions as the interferon （IFN） antagonist, mainly via suppressing TBK1/IKKε-IRF3 signaling. NSs mediates the formation of cytoplasmic inclusion bodies （IBs）, and the blockage of IB formation impairs IFN-inhibiting activity of NSs. We next demonstrate that I Bs are utilized to compartmentalize TBK1/I KKε. The compartmentalization results in spatial isolation of the kinases from mitochondria, and deprived TBK1/IKKε may participate in antiviral complex assembly, leadingto the blockage of lFN ind uction. This study proposes a new role of viral I Bs as virus-built＇jail＇ for imprisoning cellular factors and presents a novel and likely common mechanism of viral immune evasion through spatial isolation of critical signaling molecules from the mitochondrial antiviral platform.展开更多
In order to measure the axial flowing velocity of carbon particle suspension with particle diameter of tens of micrometers, the photoacoustic Doppler(PAD) frequency shift is calculated based on a series of individual ...In order to measure the axial flowing velocity of carbon particle suspension with particle diameter of tens of micrometers, the photoacoustic Doppler(PAD) frequency shift is calculated based on a series of individual A scans using an autocorrelation method. A 532 nm pulsed laser with repetition rate of 20 Hz is used as a pumping source to generate photoacoustic signal. The photoacoustic signals are detected using a focused piezoelectric(PZT) ultrasound transducer with central frequency of 5 MHz. The suspension of carbon particles is driven by a syringe pump. The complex photoacoustic signal is calculated by the Hilbert transformation from time-domain photoacoustic signal, and then it is autocorrelated to calculate the Doppler frequency shift. The photoacoustic Doppler frequency shift is calculated by averaging the autocorrelation results of some individual A scans. The advantage of the autocorrelation method is that the time delay in autocorrelation can be defined by user, and the requirement of high pulse repetition rate is avoided. The feasibility of the proposed autocorrelation method is preliminarily demonstrated by quantifying the motion of a carbon particle suspension with flow velocity from 5 mm/s to 60 mm/s. The experimental results show that there is an approximately linear relation between the autocorrelation result and the setting velocity.展开更多
In this work,acoustic vector characteristics of near fields scattered by an underwater finite cylindrical baffle are investigated theoretically and experimentally.The analytic expressions for the scattered pressure an...In this work,acoustic vector characteristics of near fields scattered by an underwater finite cylindrical baffle are investigated theoretically and experimentally.The analytic expressions for the scattered pressure and particle velocity are derived using the elastic thin shell theory.Calculations are presented for the scattered near fields of the pressure,the particle velocity and the intensity.It is found that the pressure and the particle velocity fields near the surface of the cylindrical baffle are characterized by complex interference structure,particle velocity directions and the source bearings are not consistent.The phase difference between the pressure and the particle velocity is not zero and the intensity vector does not reflect the sound bearings.It can be noted that the distortions of the fields will make the original vector signal processing method based on the free space assumption be no longer applicable in the presence of the cylindrical baffle.These results can serve as a basis of the application for the acoustic vector sensor on board.展开更多
In this work, a double signal amplified immunosen- sor based on the enhanced CdSe@ZnS quantum dots （QDs） electrochemiluminescence （ECL） via TiO2 nanoparticles （TiO2 NPs） and the outstanding quencher of polydopam...In this work, a double signal amplified immunosen- sor based on the enhanced CdSe@ZnS quantum dots （QDs） electrochemiluminescence （ECL） via TiO2 nanoparticles （TiO2 NPs） and the outstanding quencher of polydopamine （PDA） decorated Au nanoparticles （Au@PDA NPs） for ultrasensitive detection of carcinoembryonic antigen （CEA） has been successfully achieved. The ECL of CdSe@ZnS QDs with different sizes has been investigated carefully, especially cooperation with TiO2 NPs. Au@PDA NPs have been synthesized and characterized by transmission electron microscopy （TEM） and UV-Vis spectrum, which acted as ECL quenchers to label the secondary antibody （Ab2） of CEA to form Ab2/Au@PDA NPs conjugates. The sandwich-structured immunosensor was formed between capture antibody （Abl） on CdSe@ZnS QDs/TiO2 NPs/glassy carbon electrode, CEA and Ab2/Au@PDA NPs conjugates, resulting in a proportional ECL quenching signal relevant to the CEA concentration. Thus, CEA as a model biomarker has been detected in the linear range from 0.001 to 100 ng mL^-1 with a limit of detection of 0.35 pg mL^-1 （S/N = 3）.展开更多
In order to measure the flow velocity of carbon particle suspension perpendicular to the receiving axis of ultrasound transducer, the standard deviation of photoacoustic Doppler frequency spectrum is used to estimate ...In order to measure the flow velocity of carbon particle suspension perpendicular to the receiving axis of ultrasound transducer, the standard deviation of photoacoustic Doppler frequency spectrum is used to estimate the bandwidth broadening, and the spectrum standard deviation is calculated by an auto-correlation method. A 532 nm pulsed laser with the repetition rate of 20 Hz is used as a pumping source to generate photoacoustic signal. The photoacoustic signals are detected using a focused PZT ultrasound transducer with the central frequency of 10 MHz. The suspension of carbon particles is driven by a syringe pump. The complex photoacoustic signal is calculated by Hilbert transformation from time domain signal before auto-correlation. The standard deviation of the Doppler bandwidth broadening is calculated by averaging the auto-correlation results of several individual A scans. The feasibility of the proposed method is demonstrated by measuring the spectrum standard deviation of the transversal carbon particle flow from 5.0 mm/s to 8.4 mrn/s. The experimental results show that the auto-correlation result is approximately linearly distributed within the measuring range.展开更多
文摘To effectively extract the interturn short circuit fault features of induction motor from stator current signal, a novel feature extraction method based on the bare-bones particle swarm optimization （BBPSO） algorithm and wavelet packet was proposed. First, according to the maximum inner product between the current signal and the cosine basis functions, this method could precisely estimate the waveform parameters of the fundamental component using the powerful global search capability of the BBPSO, which can eliminate the fundamental component and not affect other harmonic components. Then, the harmonic components of residual current signal were decomposed to a series of frequency bands by wavelet packet to extract the interturn circuit fault features of the induction motor. Finally, the results of simulation and laboratory tests demonstrated the effectiveness of the proposed method.
基金supported by the National Natural Science Foundation of China (21025522 & 20890021)the National Natural Science Foundation of China for Creative Research Groups (20821063)the National Basic Research Program of China (2007CB936404)
文摘A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magnetic particles (MNPs) for the immobilization of linker DNA and CdS NPs and the subsequent target DNA hybridization. Using the unique characteristic of nicking endonuclease for cutting one specific strand of double strand DNA (ds DNA), the linker DNA could be transected and the target DNA could be liberated for re-hybridization and hence the amount of released CdS NPs was enhanced. Due to the advantage of the MNPs and signal amplification from the target recycling, the analyte DNA could be detected by the square-wave stripping voltammetry (SWV) in a wide linear range from 0.4 fM to 100 fM with the detection limit down to 0.08 fM. The proposed DNA detection strategy possesses high sensitivity, satisfactory reproducibility and excellent stability, which might have potential in other DNA biological assays.
基金Acknowtedgements We thank Dr Hong-Bing Shu （Wuhan University, China） for supplying reporter and expression plasmids. This work was supported by the National Science Foundation of China （grant numbers 31125003 and 31321001）, the Science and Technology Basic Work Program （grant number 2013FY113500）, and the National Basic Research Program （973 Program） of China （grant numbers 2010CB530100 and 2013CB911101）.
文摘For antiviral signaling mediated by retinoic acid-inducible gene I （RiG-I）-like receptors （RLRs）, the recruitment of cytosoUc RLRs and downstream molecules （such as TBK1 and IKKε） to mitochondriaL platform is a central event that facilitates the establishment of host antiviral state. Here, we present an example of viral targeting for immune evasion through spatial isolation of TBK1/IKKε from mitochond riai antiviral platform, which was employed by severe fever with thrombocytopenia syndrome virus （SFTSV）, a deadly bunyavirus emerging recently. We showed that SFTSV nonstructural protein NSs functions as the interferon （IFN） antagonist, mainly via suppressing TBK1/IKKε-IRF3 signaling. NSs mediates the formation of cytoplasmic inclusion bodies （IBs）, and the blockage of IB formation impairs IFN-inhibiting activity of NSs. We next demonstrate that I Bs are utilized to compartmentalize TBK1/I KKε. The compartmentalization results in spatial isolation of the kinases from mitochondria, and deprived TBK1/IKKε may participate in antiviral complex assembly, leadingto the blockage of lFN ind uction. This study proposes a new role of viral I Bs as virus-built＇jail＇ for imprisoning cellular factors and presents a novel and likely common mechanism of viral immune evasion through spatial isolation of critical signaling molecules from the mitochondrial antiviral platform.
基金supported by the Joint Funds of the National Natural Science Foundation of China(No.U1204612)Natural Science Foundation of He’nan Educational Committee(No.13A416180)
文摘In order to measure the axial flowing velocity of carbon particle suspension with particle diameter of tens of micrometers, the photoacoustic Doppler(PAD) frequency shift is calculated based on a series of individual A scans using an autocorrelation method. A 532 nm pulsed laser with repetition rate of 20 Hz is used as a pumping source to generate photoacoustic signal. The photoacoustic signals are detected using a focused piezoelectric(PZT) ultrasound transducer with central frequency of 5 MHz. The suspension of carbon particles is driven by a syringe pump. The complex photoacoustic signal is calculated by the Hilbert transformation from time-domain photoacoustic signal, and then it is autocorrelated to calculate the Doppler frequency shift. The photoacoustic Doppler frequency shift is calculated by averaging the autocorrelation results of some individual A scans. The advantage of the autocorrelation method is that the time delay in autocorrelation can be defined by user, and the requirement of high pulse repetition rate is avoided. The feasibility of the proposed autocorrelation method is preliminarily demonstrated by quantifying the motion of a carbon particle suspension with flow velocity from 5 mm/s to 60 mm/s. The experimental results show that there is an approximately linear relation between the autocorrelation result and the setting velocity.
基金supported by the Special Foundation for the State Major Basic Research Program of China (Grant No. 40827003)
文摘In this work,acoustic vector characteristics of near fields scattered by an underwater finite cylindrical baffle are investigated theoretically and experimentally.The analytic expressions for the scattered pressure and particle velocity are derived using the elastic thin shell theory.Calculations are presented for the scattered near fields of the pressure,the particle velocity and the intensity.It is found that the pressure and the particle velocity fields near the surface of the cylindrical baffle are characterized by complex interference structure,particle velocity directions and the source bearings are not consistent.The phase difference between the pressure and the particle velocity is not zero and the intensity vector does not reflect the sound bearings.It can be noted that the distortions of the fields will make the original vector signal processing method based on the free space assumption be no longer applicable in the presence of the cylindrical baffle.These results can serve as a basis of the application for the acoustic vector sensor on board.
基金supported by the National Natural Science Foundation of China (21575022, 21535003)the National High Technology Research and Development Program of China (2015AA020502)+1 种基金the Open Research Fund of Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Southeast Universitythe Fundamental Research Funds for the Central Universities (KYLX15-0127)
文摘In this work, a double signal amplified immunosen- sor based on the enhanced CdSe@ZnS quantum dots （QDs） electrochemiluminescence （ECL） via TiO2 nanoparticles （TiO2 NPs） and the outstanding quencher of polydopamine （PDA） decorated Au nanoparticles （Au@PDA NPs） for ultrasensitive detection of carcinoembryonic antigen （CEA） has been successfully achieved. The ECL of CdSe@ZnS QDs with different sizes has been investigated carefully, especially cooperation with TiO2 NPs. Au@PDA NPs have been synthesized and characterized by transmission electron microscopy （TEM） and UV-Vis spectrum, which acted as ECL quenchers to label the secondary antibody （Ab2） of CEA to form Ab2/Au@PDA NPs conjugates. The sandwich-structured immunosensor was formed between capture antibody （Abl） on CdSe@ZnS QDs/TiO2 NPs/glassy carbon electrode, CEA and Ab2/Au@PDA NPs conjugates, resulting in a proportional ECL quenching signal relevant to the CEA concentration. Thus, CEA as a model biomarker has been detected in the linear range from 0.001 to 100 ng mL^-1 with a limit of detection of 0.35 pg mL^-1 （S/N = 3）.
基金supported by the Joint Funds of the National Natural Science Foundation of China(No.U1204612)the Natural Science Foundation of He’nan Educational Committee(No.13A416180)
文摘In order to measure the flow velocity of carbon particle suspension perpendicular to the receiving axis of ultrasound transducer, the standard deviation of photoacoustic Doppler frequency spectrum is used to estimate the bandwidth broadening, and the spectrum standard deviation is calculated by an auto-correlation method. A 532 nm pulsed laser with the repetition rate of 20 Hz is used as a pumping source to generate photoacoustic signal. The photoacoustic signals are detected using a focused PZT ultrasound transducer with the central frequency of 10 MHz. The suspension of carbon particles is driven by a syringe pump. The complex photoacoustic signal is calculated by Hilbert transformation from time domain signal before auto-correlation. The standard deviation of the Doppler bandwidth broadening is calculated by averaging the auto-correlation results of several individual A scans. The feasibility of the proposed method is demonstrated by measuring the spectrum standard deviation of the transversal carbon particle flow from 5.0 mm/s to 8.4 mrn/s. The experimental results show that the auto-correlation result is approximately linearly distributed within the measuring range.
