Background : SOX6 has been shown to play a crucial role in the development of the cardiovascular system. However, its potential role in hypertension and vascular function remains unclear. Methods : In vascular smooth ...Background : SOX6 has been shown to play a crucial role in the development of the cardiovascular system. However, its potential role in hypertension and vascular function remains unclear. Methods : In vascular smooth muscle cells(VSMCs), we employed gain-and loss-offunction approaches combined with RNA sequencing, autophagy flux assessment, and phenotype characterization. Additionally, we established a mouse model with Sox6 overexpression via adeno-associated virus 2(AAV2) to validate the findings in vivo. Results : We validated the increased expression of SOX6 in hypertension both in vitro and in vivo. Genetic silencing of Sox6 in VSMCs attenuated the phenotypic switching induced by angiotensin Ⅱ. Conversely, in vivo overexpression of Sox6 led to a significant elevation in blood pressure and promoted vascular remodeling. Mechanistically, SOX6 was shown to regulate phenotypic switching via an autophagydependent pathway. Specifically, Sox6 overexpression augmented VSMC autophagy and facilitated phenotypic switching, whereas Sox6 knockdown yielded opposite outcomes. Modulation of autophagy using 3-MA or RAPA could effectively counteract the effect mediated by SOX6. Conclusions : Our findings revealed that SOX6 regulates VSMC plasticity and elevates blood pressure by activating autophagy. Therefore, SOX6 inhibition potentially represents a novel strategy for treating hypertension and vascular remodeling.展开更多
Acoustic array sensor device for partial discharge detection is widely used in power equipment inspection with the advantages of non-contact and precise positioning compared with partial discharge detection methods su...Acoustic array sensor device for partial discharge detection is widely used in power equipment inspection with the advantages of non-contact and precise positioning compared with partial discharge detection methods such as ultrasonic method and pulse current method.However,due to the sensitivity of the acoustic array sensor and the influence of the equipment operation site interference,the acoustic array sensor device for partial discharge type diagnosis by phase resolved partial discharge(PRPD)map might occasionally presents incorrect results,thus affecting the power equipment operation and maintenance strategy.The acoustic array sensor detection device for power equipment developed in this paper applies the array design model of equal-area multi-arm spiral with machine learning fast fourier transform clean(FFT-CLEAN)sound source localization identification algorithm to avoid the interference factors in the noise acquisition system using a single microphone and conventional beam forming algorithm,improves the spatial resolution of the acoustic array sensor device,and proposes an acoustic array sensor device based on the acoustic spectrogram.The analysis and diagnosis method of discharge type of acoustic array sensor device can effectively reduce the system misjudgment caused by factors such as the resolution of the acoustic imaging device and the time domain pulse of the digital signal,and reduce the false alarm rate of the acoustic array sensor device.The proposed method is tested by selecting power cables as the object,and its effectiveness is proved by laboratory verification and field verification.展开更多
The pulse current method,acoustic and ultrasonic partial discharge(PD)detection,and voiceprint PD detection are commonly used detection methods for the PD detection of power equipment.To study the characteristics of P...The pulse current method,acoustic and ultrasonic partial discharge(PD)detection,and voiceprint PD detection are commonly used detection methods for the PD detection of power equipment.To study the characteristics of PD signals of typical discharge models based on the principles of the above three detection methods,an acoustic detection experimental system consisting of a needle-tip model and a surface model was built.Acoustic tests were carried out on needle-tip models with different curvature radii and surface discharge models with different lengths of conductive paste.The experimental results showed that acoustic and ultrasonic PD detection and voiceprint PD detection exhibited different sensitivities to the needle-tip discharge models,and the combination of acoustic and ultrasonic PD and voiceprint PD detection was more beneficial for the comprehensive detection of cable PD signals.Based on voiceprint recognition technology,this study drew FFT(Fast Fourier Transformation)diagrams of different types of PD acoustic signals and analyzed the differences in the ultrasonic signal frequency distribution.The frequency band of the voiceprint PD signal of the needle-tip discharge models was concentrated in the range 17-27 kHz,and the frequency band of the voiceprint PD signal of the conductive paste discharge models was concentrated in the range 20-25 kHz.The measurement of voiceprint PD signals in these frequency bands were strengthened when the PD of a cable was detected on-site,which provides the basis for the use of the cable model for on-site PD detection.展开更多
The development of surface-enhanced Raman scattering(SERS)devices for detection of trace pesticides has attracted more and more attention.In this work,a large-area self-assembly ap-proach assisted with reactive ion et...The development of surface-enhanced Raman scattering(SERS)devices for detection of trace pesticides has attracted more and more attention.In this work,a large-area self-assembly ap-proach assisted with reactive ion etching(RIE)is proposed for preparing SERS devices consisting of Ag-covered"hedgehog-like"nanosphere arrays(Ag/HLNAs).Such a SERS device has an enhancement factor of 2.79×107,a limit of detection(LOD)up to 10-12 M for Rhodamine 6G(R6G)analytes,and a relative standard deviation(RSD)smaller than 10%,demonstrating high uniformity.Besides,for pesticide detections,the device achieves an LOD of 10-s M for thiram molecules.It indicates that the proposed SERS device has a promising opportunity in detecting toxic organic pesticides.展开更多
The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,puri...The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,purification,as well as viability rates of rare target cells as the prerequisites for high sensitivity,specificity,and accuracy of tumor cell analysis.In this paper,we propose a three-dimensional(3 D)sieving method for rare tumor cell enrichment,which effectively eliminates the"dead zones"in traditional two-dimensional(2 D)cell filters with a dimension-raising strategy to satisfy the requirements mentioned above.The prototype device was combined with a funnel-shaped holder,a flexible micropore membrane in the middle,and a3 D spiral fluid channel covered on the membrane as a three-layer ice-creaming cone composite structure.Driven by gravity alone,the device performed as follows:(1)20-fold throughput compared with the 2 D commercial planee hich was up to 20 mL/min for a threefold dilution of whole blood sample;(2)high recovery rates of 84.5%±21%,86%±25%,83%±14%for 100,1000,and 10000 cells/mL,respectively,in 30 mL phosphate buffer saline(PBS)sample,and a 100%positive detection rate in the case of≤5 A549 cells in 1 mL PBS;(3)a typical purification rate of 85.5%±9.1%;and(4)a viability rate of>93%.In the demonstration application,this device effectively enriched rare target cells from large volumes(>25 mL)of clinical pleural effusions.The following results indicated that tumor cells were easy-to-discover in the enriched PE samples,and the proliferation capability of purified cells was(>4.6 times)significantly stronger than that of unprocessed cells in the subsequent 6-day culture.The above evaluation indicates that the proposed easily reproducible method for the effective execution of rare cell enrichments and assays is expected to become a practical technique for clinical cell-based tumor diagnosis.展开更多
An intelligent humidity sensing system has been developed for real-time monitoring of human behaviors through respiration detection.The key component of this system is a humidity sensor that integrates a thermistor an...An intelligent humidity sensing system has been developed for real-time monitoring of human behaviors through respiration detection.The key component of this system is a humidity sensor that integrates a thermistor and a micro-heater.This sensor employs porous nanoforests as its sensing material,achieving a sensitivity of 0.56 pF/%RH within a range of 60–90%RH,along with excellent long-term stability and superior gas selectivity.The micro-heater in the device provides a high operating temperature,enhancing sensitivity by 5.8 times.This significant improvement enables the capture of weak humidity variations in exhaled gases,while the thermistor continuously monitors the sensor’s temperature during use and provides crucial temperature information related to respiration.With the assistance of a machine learning algorithm,a behavior recognition system based on the humidity sensor has been constructed,enabling behavior states to be classified and identified with an accuracy of up to 96.2%.This simple yet intelligent method holds great potential for widespread applications in medical assistance analysis and daily health monitoring.展开更多
Exosomes are highly important in clinical diagnosis due to their high homology with their parental cells.However,conventional exosome detection methods still face the challenges of expensive equipment,low sensitivity,...Exosomes are highly important in clinical diagnosis due to their high homology with their parental cells.However,conventional exosome detection methods still face the challenges of expensive equipment,low sensitivity,and complex procedures.Field effect transistors(FETs)are not only the most essential electronic component in the modern microelectronics industry but also show great potential for biomolecule detection owing to the advantages of rapid response,high sensitivity,and label-free detection.In this study,we proposed a Si nanowire field-effect transistor(Si-NW Bio-FET)device chemically modified with specific antibodies for the electrical and label-free detection of exosomes.The Si-NW FETs were fabricated by standard microelectronic processes with 45 nm width nanowires and packaged in a polydimethylsiloxane(PDMS)microfluidic channel.The nanowires were further modified with the specific CD63 antibody to form a Si-NW Bio-FET.The use of the developed Si-NW Bio-FET for the electrical and labelfree detection of exosomes was successfully demonstrated with a limit of detection(LOD)of 2159 particles/mL.In contrast to other technologies,in this study,Si-NW Bio-FET provides a unique strategy for directly quantifying and realtime detecting exosomes without labeling,indicating its potential as a tool for the early diagnosis of cancer.展开更多
We report the observation of second order Bragg resonance(2 nd-OBG) produced by tilted fiber gratings(TFGs) fabricated using phase mask UV inscription.The theoretical analysis has revealed that the generation of high ...We report the observation of second order Bragg resonance(2 nd-OBG) produced by tilted fiber gratings(TFGs) fabricated using phase mask UV inscription.The theoretical analysis has revealed that the generation of high order Bragg resonance of gratings is induced by a square-shape refractive index profile,which is caused by over-saturated UV exposure.In the experiment,we have studied the TFGs with different tilt angles under over-saturated UV exposure,in which all gratings have showed the 2 nd-OBR,and the larger tilt angle of the grating has the stronger 2 nd-OBR.When the tilt angle of the grating is-45°,the Bragg resonance exhibits very strong polarization dependence,because the 2 nd-OBR wavelength is located within the polarizing bandwidth of 45° TFG.Finally,we have demonstrated an erbium-doped fiber laser with> 99.9% degree of polarization,and,by applying mechanical stretching on the grating,a wavelength tunable laser output has been achieved.The output laser shows ~0.2 dB amplitude variation within 1 h continuous monitoring of the laser.展开更多
Directionally scattered surface plasmon polaritons(SPPs)promote the efficiency of plasmonic devices by limiting the energy within a given spatial domain,which is one of the key issues to plasmonic devices.Benefitting ...Directionally scattered surface plasmon polaritons(SPPs)promote the efficiency of plasmonic devices by limiting the energy within a given spatial domain,which is one of the key issues to plasmonic devices.Benefitting from the magnetic response induced in high-index dielectric nanoparticles,unidirectionally scattered SPPs have been achieved via interference between electric and magnetic resonances excited in the particles.Yet,as the magnetic response in low-index dielectric nanoparticles is too weak,the directionally scattered SPPs are hard to detect.In this work,we demonstrate forward scattered SPPs in single low-index polystyrene(PS)nanospheres.We numerically illustrate the excitation mechanism of plasmonic induced electric and magnetic multipole modes,as well as their contributions to forward SPP scattering of single PS nanospheres.We also simulate the SPP scattering field distribution obtaining a forward-to-backward scattering intensity ratio of 50.26:1 with 1μm PS particle.Then the forward scattered SPPs are experimentally visualized by Fourier transforming the real-space plasmonic imaging to k-space imaging.The forward scattered SPPs from low-index dielectric nanoparticles pave the way for SPP direction manipulation by all types of nanomaterials.展开更多
Wearable ultrasound imaging technology has become an emerging modality for the continuous monitoring of deep-tissue physiology,providing crucial health and disease information.Fast volumetric imaging that can provide ...Wearable ultrasound imaging technology has become an emerging modality for the continuous monitoring of deep-tissue physiology,providing crucial health and disease information.Fast volumetric imaging that can provide a full spatiotemporal view of intrinsic 3D targets is desirable for interpreting internal organ dynamics.However,existing 1D ultrasound transducer arrays provide 2D images,making it challenging to overcome the trade-off between the temporal resolution and volumetric coverage.In addition,the high driving voltage limits their implementation in wearable settings.With the use of microelectromechanical system(MEMS)technology,we report an ultrasonic phased-array transducer,i.e.,a 2D piezoelectric micromachined ultrasound transducer(pMUT)array,which is driven by a low voltage and is chip-compatible for fast 3D volumetric imaging.By grouping multiple pMUT cells into one single drive channel/element,we propose an innovative cell–element–array design and operation of a pMUT array that can be used to quantitatively characterize the key coupling effects between each pMUT cell,allowing 3D imaging with 5-V actuation.The pMUT array demonstrates fast volumetric imaging covering a range of 40 mm×40 mm×70 mm in wire phantom and vascular phantom experiments,achieving a high temporal frame rate of 11 kHz.The proposed solution offers a full volumetric view of deep-tissue disorders in a fast manner,paving the way for long-term wearable imaging technology for various organs in deep tissues.展开更多
Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be detec...Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be detected.Microfluidic techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing regions.However,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale channels.In this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and speed.To demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91%of passed microbeads.Subsequently,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the chip.As representative results,~0.63,2.62,11.78,and 19.75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 100,10,1,and 0.1 ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar level.Our results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.展开更多
Real-time transformation was important for the practical implementation of impedance flow cytometry.The major obstacle was the time-consuming step of translating raw data to cellular intrinsic electrical properties(e....Real-time transformation was important for the practical implementation of impedance flow cytometry.The major obstacle was the time-consuming step of translating raw data to cellular intrinsic electrical properties(e.g.,specific membrane capacitance C_(sm) and cytoplasm conductivityσ_(cyto)).Although optimization strategies such as neural network-aided strategies were recently reported to provide an impressive boost to the translation process,simultaneously achieving high speed,accuracy,and generalization capability is still challenging.To this end,we proposed a fast parallel physical fitting solver that could characterize single cells’C_(sm)andσ_(cyto)within 0.62 ms/cell without any data preacquisition or pretraining requirements.We achieved the 27000-fold acceleration without loss of accuracy compared with the traditional solver.Based on the solver,we implemented physics-informed real-time impedance flow cytometry(piRT-IFC),which was able to characterize up to 100,902 cells’C_(sm) andσ_(cyto)within 50 min in a real-time manner.Compared to the fully connected neural network(FCNN)predictor,the proposed real-time solver showed comparable processing speed but higher accuracy.Furthermore,we used a neutrophil degranulation cell model to represent tasks to test unfamiliar samples without data for pretraining.After being treated with cytochalasin B and N-Formyl-Met-Leu-Phe,HL-60 cells underwent dynamic degranulation processes,and we characterized cell’s C_(sm)andσ_(cyto)using piRT-IFC.Compared to the results from our solver,accuracy loss was observed in the results predicted by the FCNN,revealing the advantages of high speed,accuracy,and generalizability of the proposed piRT-IFC.展开更多
Achieving passive microparticle filtration with micropore membranes is challenging due to the capillary pinning effect of the membranes.Inspired by the teapot effect that occurs when liquid(tea)is poured from a teapot...Achieving passive microparticle filtration with micropore membranes is challenging due to the capillary pinning effect of the membranes.Inspired by the teapot effect that occurs when liquid(tea)is poured from a teapot spout,we proposed a tap-triggered self-wetting strategy and utilized the method with a 3D sieve to flter rare cells.First,a 3D-printed polymer tap-trigger microstructure was implemented.As a result,the 3μm micropore membrane gating threshold(the pressure needed to open the micropores)was lowered from above 3000 to 80 Pa by the tap-trigger microstructure that facilated the liquid leakage and spreading to self-wet more membrane area in a positive feedback loop.Then,we implemented a 3D cone-shaped cell sieve with tap-trigger microstructures.Driven by gravity,the sieve performed at a high throughput above 20 mL/min(DPBS),while the micropore size and porosity were 3μm and 14.1%,respectively.We further filtered leukocytes from whole blood samples with the proposed new 3D sieve,and the method was compared with the traditional method of leukocyte isolation by chemically removing red blood cells.The device exhibited comparable leukocyte purity but a higher platelet removal rate and lower leukocyte simulation level,facilitating downstream single-cell analysis.The key results indicated that the tap-triggered self-wetting strategy could significantly improve the performance of passive microparticle filtration.展开更多
基金Beijing Nova Program,Grant/Award Number:20230484842National Natural Science Foundation of China,Grant/Award Number:82470461。
文摘Background : SOX6 has been shown to play a crucial role in the development of the cardiovascular system. However, its potential role in hypertension and vascular function remains unclear. Methods : In vascular smooth muscle cells(VSMCs), we employed gain-and loss-offunction approaches combined with RNA sequencing, autophagy flux assessment, and phenotype characterization. Additionally, we established a mouse model with Sox6 overexpression via adeno-associated virus 2(AAV2) to validate the findings in vivo. Results : We validated the increased expression of SOX6 in hypertension both in vitro and in vivo. Genetic silencing of Sox6 in VSMCs attenuated the phenotypic switching induced by angiotensin Ⅱ. Conversely, in vivo overexpression of Sox6 led to a significant elevation in blood pressure and promoted vascular remodeling. Mechanistically, SOX6 was shown to regulate phenotypic switching via an autophagydependent pathway. Specifically, Sox6 overexpression augmented VSMC autophagy and facilitated phenotypic switching, whereas Sox6 knockdown yielded opposite outcomes. Modulation of autophagy using 3-MA or RAPA could effectively counteract the effect mediated by SOX6. Conclusions : Our findings revealed that SOX6 regulates VSMC plasticity and elevates blood pressure by activating autophagy. Therefore, SOX6 inhibition potentially represents a novel strategy for treating hypertension and vascular remodeling.
基金This work was supported by the science and technology project of State Grid Shanghai Municipal Electric Power Company(No.52090020007F)National Key R&D Program of China(2017YFB0902800).
文摘Acoustic array sensor device for partial discharge detection is widely used in power equipment inspection with the advantages of non-contact and precise positioning compared with partial discharge detection methods such as ultrasonic method and pulse current method.However,due to the sensitivity of the acoustic array sensor and the influence of the equipment operation site interference,the acoustic array sensor device for partial discharge type diagnosis by phase resolved partial discharge(PRPD)map might occasionally presents incorrect results,thus affecting the power equipment operation and maintenance strategy.The acoustic array sensor detection device for power equipment developed in this paper applies the array design model of equal-area multi-arm spiral with machine learning fast fourier transform clean(FFT-CLEAN)sound source localization identification algorithm to avoid the interference factors in the noise acquisition system using a single microphone and conventional beam forming algorithm,improves the spatial resolution of the acoustic array sensor device,and proposes an acoustic array sensor device based on the acoustic spectrogram.The analysis and diagnosis method of discharge type of acoustic array sensor device can effectively reduce the system misjudgment caused by factors such as the resolution of the acoustic imaging device and the time domain pulse of the digital signal,and reduce the false alarm rate of the acoustic array sensor device.The proposed method is tested by selecting power cables as the object,and its effectiveness is proved by laboratory verification and field verification.
基金supported by the science and technology project of State Grid Shanghai Municipal Electric Power Company (No. 52090020007F)National Key R&D Program of China (2017YFB0902800)。
文摘The pulse current method,acoustic and ultrasonic partial discharge(PD)detection,and voiceprint PD detection are commonly used detection methods for the PD detection of power equipment.To study the characteristics of PD signals of typical discharge models based on the principles of the above three detection methods,an acoustic detection experimental system consisting of a needle-tip model and a surface model was built.Acoustic tests were carried out on needle-tip models with different curvature radii and surface discharge models with different lengths of conductive paste.The experimental results showed that acoustic and ultrasonic PD detection and voiceprint PD detection exhibited different sensitivities to the needle-tip discharge models,and the combination of acoustic and ultrasonic PD and voiceprint PD detection was more beneficial for the comprehensive detection of cable PD signals.Based on voiceprint recognition technology,this study drew FFT(Fast Fourier Transformation)diagrams of different types of PD acoustic signals and analyzed the differences in the ultrasonic signal frequency distribution.The frequency band of the voiceprint PD signal of the needle-tip discharge models was concentrated in the range 17-27 kHz,and the frequency band of the voiceprint PD signal of the conductive paste discharge models was concentrated in the range 20-25 kHz.The measurement of voiceprint PD signals in these frequency bands were strengthened when the PD of a cable was detected on-site,which provides the basis for the use of the cable model for on-site PD detection.
基金This work was supported in part by the National Natural Science Foundation of China(61771467,61774167,and 61801477)National Key Research and Devel opment Program of China(2018YFC2001100)+1 种基金Youth Innovation Promotion Association,Chinese Academy of Sciences(2018153)Key-Area Research and Devel opment Program of Guangdong Province(2019B010117001).
文摘The development of surface-enhanced Raman scattering(SERS)devices for detection of trace pesticides has attracted more and more attention.In this work,a large-area self-assembly ap-proach assisted with reactive ion etching(RIE)is proposed for preparing SERS devices consisting of Ag-covered"hedgehog-like"nanosphere arrays(Ag/HLNAs).Such a SERS device has an enhancement factor of 2.79×107,a limit of detection(LOD)up to 10-12 M for Rhodamine 6G(R6G)analytes,and a relative standard deviation(RSD)smaller than 10%,demonstrating high uniformity.Besides,for pesticide detections,the device achieves an LOD of 10-s M for thiram molecules.It indicates that the proposed SERS device has a promising opportunity in detecting toxic organic pesticides.
基金supported by the National Key Research and Development Program of China(No.2018YFC2001100)the National Natural Science Foundation of China(Nos.61774167 and 61801477)+2 种基金the Instrument Development Program of the Chinese Academy of Sciences,Beijing Municipal Natural Science Foundation(Nos.4192062 and 4182072)Beijing Municipal Administration of Hospitals Incubating Program(No.PX2017050)Youth Innovation Promotion Association of Chinese Academy of Sciences。
文摘The sieving and enrichment of rare tumor cells from large-volume pleural effusion(PE)samples is a promising technique for cell-based lung tumor diagnosis and drug tests,which features high throughput and recovery,purification,as well as viability rates of rare target cells as the prerequisites for high sensitivity,specificity,and accuracy of tumor cell analysis.In this paper,we propose a three-dimensional(3 D)sieving method for rare tumor cell enrichment,which effectively eliminates the"dead zones"in traditional two-dimensional(2 D)cell filters with a dimension-raising strategy to satisfy the requirements mentioned above.The prototype device was combined with a funnel-shaped holder,a flexible micropore membrane in the middle,and a3 D spiral fluid channel covered on the membrane as a three-layer ice-creaming cone composite structure.Driven by gravity alone,the device performed as follows:(1)20-fold throughput compared with the 2 D commercial planee hich was up to 20 mL/min for a threefold dilution of whole blood sample;(2)high recovery rates of 84.5%±21%,86%±25%,83%±14%for 100,1000,and 10000 cells/mL,respectively,in 30 mL phosphate buffer saline(PBS)sample,and a 100%positive detection rate in the case of≤5 A549 cells in 1 mL PBS;(3)a typical purification rate of 85.5%±9.1%;and(4)a viability rate of>93%.In the demonstration application,this device effectively enriched rare target cells from large volumes(>25 mL)of clinical pleural effusions.The following results indicated that tumor cells were easy-to-discover in the enriched PE samples,and the proliferation capability of purified cells was(>4.6 times)significantly stronger than that of unprocessed cells in the subsequent 6-day culture.The above evaluation indicates that the proposed easily reproducible method for the effective execution of rare cell enrichments and assays is expected to become a practical technique for clinical cell-based tumor diagnosis.
基金supported by National Natural Science Foundation of China(Grant Nos.62474192 and 62201567)Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant Nos.2022048 and 2022117)State Key Laboratory of Dynamic Test jointly built by Province and Ministry Open Fund(Grant No.2022-SYSJJ-07).
文摘An intelligent humidity sensing system has been developed for real-time monitoring of human behaviors through respiration detection.The key component of this system is a humidity sensor that integrates a thermistor and a micro-heater.This sensor employs porous nanoforests as its sensing material,achieving a sensitivity of 0.56 pF/%RH within a range of 60–90%RH,along with excellent long-term stability and superior gas selectivity.The micro-heater in the device provides a high operating temperature,enhancing sensitivity by 5.8 times.This significant improvement enables the capture of weak humidity variations in exhaled gases,while the thermistor continuously monitors the sensor’s temperature during use and provides crucial temperature information related to respiration.With the assistance of a machine learning algorithm,a behavior recognition system based on the humidity sensor has been constructed,enabling behavior states to be classified and identified with an accuracy of up to 96.2%.This simple yet intelligent method holds great potential for widespread applications in medical assistance analysis and daily health monitoring.
基金support from the National Key Research and Development Program of China(2020YFC2004503)Beijing Nova Program(Z2011006820083,Z2011006820084)Beijing Municipal Natural Science Foundation(No.4192062).
文摘Exosomes are highly important in clinical diagnosis due to their high homology with their parental cells.However,conventional exosome detection methods still face the challenges of expensive equipment,low sensitivity,and complex procedures.Field effect transistors(FETs)are not only the most essential electronic component in the modern microelectronics industry but also show great potential for biomolecule detection owing to the advantages of rapid response,high sensitivity,and label-free detection.In this study,we proposed a Si nanowire field-effect transistor(Si-NW Bio-FET)device chemically modified with specific antibodies for the electrical and label-free detection of exosomes.The Si-NW FETs were fabricated by standard microelectronic processes with 45 nm width nanowires and packaged in a polydimethylsiloxane(PDMS)microfluidic channel.The nanowires were further modified with the specific CD63 antibody to form a Si-NW Bio-FET.The use of the developed Si-NW Bio-FET for the electrical and labelfree detection of exosomes was successfully demonstrated with a limit of detection(LOD)of 2159 particles/mL.In contrast to other technologies,in this study,Si-NW Bio-FET provides a unique strategy for directly quantifying and realtime detecting exosomes without labeling,indicating its potential as a tool for the early diagnosis of cancer.
基金supported in part by the National Natural Science Foundation of China (No. 62075071)the National Science Fund for Excellent Young Scholars (No. 61922033)+1 种基金the ‘111’ Project (No. D20031)the Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone applied fundamental research project (No. HZQB-KCZYB-2020082)
文摘We report the observation of second order Bragg resonance(2 nd-OBG) produced by tilted fiber gratings(TFGs) fabricated using phase mask UV inscription.The theoretical analysis has revealed that the generation of high order Bragg resonance of gratings is induced by a square-shape refractive index profile,which is caused by over-saturated UV exposure.In the experiment,we have studied the TFGs with different tilt angles under over-saturated UV exposure,in which all gratings have showed the 2 nd-OBR,and the larger tilt angle of the grating has the stronger 2 nd-OBR.When the tilt angle of the grating is-45°,the Bragg resonance exhibits very strong polarization dependence,because the 2 nd-OBR wavelength is located within the polarizing bandwidth of 45° TFG.Finally,we have demonstrated an erbium-doped fiber laser with> 99.9% degree of polarization,and,by applying mechanical stretching on the grating,a wavelength tunable laser output has been achieved.The output laser shows ~0.2 dB amplitude variation within 1 h continuous monitoring of the laser.
基金National Natural Science Foundation of China(62275246)Scientific Research Equipment Project of Chinese Academy of Sciences(YJKYYQ20190056)Deutsche Forschungsgemeinschaft(EXC 2122,390833453)。
文摘Directionally scattered surface plasmon polaritons(SPPs)promote the efficiency of plasmonic devices by limiting the energy within a given spatial domain,which is one of the key issues to plasmonic devices.Benefitting from the magnetic response induced in high-index dielectric nanoparticles,unidirectionally scattered SPPs have been achieved via interference between electric and magnetic resonances excited in the particles.Yet,as the magnetic response in low-index dielectric nanoparticles is too weak,the directionally scattered SPPs are hard to detect.In this work,we demonstrate forward scattered SPPs in single low-index polystyrene(PS)nanospheres.We numerically illustrate the excitation mechanism of plasmonic induced electric and magnetic multipole modes,as well as their contributions to forward SPP scattering of single PS nanospheres.We also simulate the SPP scattering field distribution obtaining a forward-to-backward scattering intensity ratio of 50.26:1 with 1μm PS particle.Then the forward scattered SPPs are experimentally visualized by Fourier transforming the real-space plasmonic imaging to k-space imaging.The forward scattered SPPs from low-index dielectric nanoparticles pave the way for SPP direction manipulation by all types of nanomaterials.
基金This work was supported in part by the National Key Research and Development Program of China under Grants 2023YFE0206400 and 2023YFB3608800in part by the National Natural Science Foundation of China under Grants 6217012870,62171442,62027901 and 62275264in part by the CAS-CSIRO Partnership Joint Project under Grant number 172511KYSB20210008.
文摘Wearable ultrasound imaging technology has become an emerging modality for the continuous monitoring of deep-tissue physiology,providing crucial health and disease information.Fast volumetric imaging that can provide a full spatiotemporal view of intrinsic 3D targets is desirable for interpreting internal organ dynamics.However,existing 1D ultrasound transducer arrays provide 2D images,making it challenging to overcome the trade-off between the temporal resolution and volumetric coverage.In addition,the high driving voltage limits their implementation in wearable settings.With the use of microelectromechanical system(MEMS)technology,we report an ultrasonic phased-array transducer,i.e.,a 2D piezoelectric micromachined ultrasound transducer(pMUT)array,which is driven by a low voltage and is chip-compatible for fast 3D volumetric imaging.By grouping multiple pMUT cells into one single drive channel/element,we propose an innovative cell–element–array design and operation of a pMUT array that can be used to quantitatively characterize the key coupling effects between each pMUT cell,allowing 3D imaging with 5-V actuation.The pMUT array demonstrates fast volumetric imaging covering a range of 40 mm×40 mm×70 mm in wire phantom and vascular phantom experiments,achieving a high temporal frame rate of 11 kHz.The proposed solution offers a full volumetric view of deep-tissue disorders in a fast manner,paving the way for long-term wearable imaging technology for various organs in deep tissues.
基金supported by the National Key Research and Development Program of China(No.2022YFB3207200)the National Natural Science Foundation of China(Nos.62171441,62104248).
文摘Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be detected.Microfluidic techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing regions.However,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale channels.In this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and speed.To demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91%of passed microbeads.Subsequently,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the chip.As representative results,~0.63,2.62,11.78,and 19.75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 100,10,1,and 0.1 ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar level.Our results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.
基金This work was supported by the National Key Research and Development Program of China(No.2018YFC2001100)the National Natural Science Foundation of China(No.62171441)the State Key Laboratory of Computer Architecture(ICT,CAS)under Grant No.CARCH202122.
文摘Real-time transformation was important for the practical implementation of impedance flow cytometry.The major obstacle was the time-consuming step of translating raw data to cellular intrinsic electrical properties(e.g.,specific membrane capacitance C_(sm) and cytoplasm conductivityσ_(cyto)).Although optimization strategies such as neural network-aided strategies were recently reported to provide an impressive boost to the translation process,simultaneously achieving high speed,accuracy,and generalization capability is still challenging.To this end,we proposed a fast parallel physical fitting solver that could characterize single cells’C_(sm)andσ_(cyto)within 0.62 ms/cell without any data preacquisition or pretraining requirements.We achieved the 27000-fold acceleration without loss of accuracy compared with the traditional solver.Based on the solver,we implemented physics-informed real-time impedance flow cytometry(piRT-IFC),which was able to characterize up to 100,902 cells’C_(sm) andσ_(cyto)within 50 min in a real-time manner.Compared to the fully connected neural network(FCNN)predictor,the proposed real-time solver showed comparable processing speed but higher accuracy.Furthermore,we used a neutrophil degranulation cell model to represent tasks to test unfamiliar samples without data for pretraining.After being treated with cytochalasin B and N-Formyl-Met-Leu-Phe,HL-60 cells underwent dynamic degranulation processes,and we characterized cell’s C_(sm)andσ_(cyto)using piRT-IFC.Compared to the results from our solver,accuracy loss was observed in the results predicted by the FCNN,revealing the advantages of high speed,accuracy,and generalizability of the proposed piRT-IFC.
基金supported by the National Key Research and Development Program of China(No.2018YFC2001100)the National Natural Science Foundation of China(No.62171441,82071314)the Scientific Research and Equipment Development Project of CAS(YJKYYQ20210031).
文摘Achieving passive microparticle filtration with micropore membranes is challenging due to the capillary pinning effect of the membranes.Inspired by the teapot effect that occurs when liquid(tea)is poured from a teapot spout,we proposed a tap-triggered self-wetting strategy and utilized the method with a 3D sieve to flter rare cells.First,a 3D-printed polymer tap-trigger microstructure was implemented.As a result,the 3μm micropore membrane gating threshold(the pressure needed to open the micropores)was lowered from above 3000 to 80 Pa by the tap-trigger microstructure that facilated the liquid leakage and spreading to self-wet more membrane area in a positive feedback loop.Then,we implemented a 3D cone-shaped cell sieve with tap-trigger microstructures.Driven by gravity,the sieve performed at a high throughput above 20 mL/min(DPBS),while the micropore size and porosity were 3μm and 14.1%,respectively.We further filtered leukocytes from whole blood samples with the proposed new 3D sieve,and the method was compared with the traditional method of leukocyte isolation by chemically removing red blood cells.The device exhibited comparable leukocyte purity but a higher platelet removal rate and lower leukocyte simulation level,facilitating downstream single-cell analysis.The key results indicated that the tap-triggered self-wetting strategy could significantly improve the performance of passive microparticle filtration.
