We have presented a three dimensional optical protein chip that fulfills the demanding for point-of-care diagnostics in terms of ease-of-use (one step assay), miniaturization (5 μl). The artful combination of magneti...We have presented a three dimensional optical protein chip that fulfills the demanding for point-of-care diagnostics in terms of ease-of-use (one step assay), miniaturization (5 μl). The artful combination of magnetic nanoparticles on chip and total internal reflection imaging (TIRI) technology permits the sensitive and rapid detection of hs-CRP (high-sensitivity C-reactive protein). The whole test was complete within 10 min using “all in one step” assay with a limit of detection of 0.1 ng/mL hs-CRP. The measuring range for hs-CRP could be extended to 10 ng/mL. The chip can also be used to detect more parameters in blood samples.展开更多
Anesthesia plays a crucial role in regulating physiological states during medical procedures,but its effects on neural activity remain incompletely understood,particularly at the prefrontal cortical level.The prefront...Anesthesia plays a crucial role in regulating physiological states during medical procedures,but its effects on neural activity remain incompletely understood,particularly at the prefrontal cortical level.The prefrontal cortex is essential for various cognitive and motor functions,yet high-spatiotemporal-resolution electrodes at the cellular level remain challenging to develop,which has hindered the acquisition of detailed electrophysiological data from anesthetized subjects.Here,we design a 16-channel silicon-based microelectrode array(MEA),which,after modification with platinum black nanoparticles,exhibits significantly reduced impedance(22.5 kΩ)and increased phase(−33.5°),enhancing its electrical performance and electrophysiological signal detection capabilities.Using this modified MEA,we have recorded cellular-level neural activity during the recovery process of a rhesus macaque following prolonged anesthesia.Over a 660 s period,we observed a gradual increase in the neuronal firing rate in the F7 area,along with distinctive patterns in local field potentials across different frequency bands.Notably,power in the δ and θ bands increased continuously during recovery,highlighting their potential role in the transition from anesthesia to wakefulness.Our findings provide new insights into the dynamic recovery process of cortical neurons and offer a powerful tool for high-spatiotemporal-resolution neural monitoring in nonhuman primates.展开更多
In fluorescence flow cytometry,spectral overlap among multiple fluorescent labels cannot be avoided,and thus detected fluorescent intensities need to be compensated.Although fluorescent compensation in flow cytometry ...In fluorescence flow cytometry,spectral overlap among multiple fluorescent labels cannot be avoided,and thus detected fluorescent intensities need to be compensated.Although fluorescent compensation in flow cytometry has been widely used for many years,it still lacks quantitative evaluations to validate its effectiveness.Using a home-developed nine-color fluorescence flow cytometer,this study first obtains calibration curves by assaying gradient concentrations of nine different fluorochromes individually,with the fluorescent intensities of the highest concentrations of each fluorochrome being used to obtain a spillover matrix.Mixed fluorescent solutions are analyzed by flow cytometry in which the obtained fluorescent intensities are compensated by the spillover matrix,translated to specific concentrations based on calibration curve and compared with nominal values.Three mixed solutions of Brilliant Violet 650 and Brilliant Violet 711,of Alexa Fluor 488 and PE,and of Pacific Orange,Alexa Fluor 488,and PE are tested,with fluorescent compensation being observed to reduce excessive signals due to spectral overlap.Specifically,concentration deviations(before vs after compensation)in comparison with nominal values for Brilliant Violet 711 and Alexa Fluor 488 are quantified as 40.6%vs 14.9%and 6.7%vs 1.9%,respectively.The results presented here provide a quantitative reference for fluorescent compensation that can be used to effectively address the issue of spectral overlap in fluorescence flow cytometry.展开更多
Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize...Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize electrical stimulation to directly or indirectly target specific brain regions,modulating neural activity and influencing broader brain networks,thereby regulating cognitive function.Regulating cognitive function involves an understanding of aspects such as perception,learning and memory,attention,spatial cognition,and physical function.To enhance the application of cognitive regulation in the general population,this paper reviews recent publications from the Web of Science to assess the advancements and challenges of invasive and non-invasive stimulation methods in modulating cognitive functions.This review covers various neuromodulation techniques for cognitive intervention,including deep brain stimulation,vagus nerve stimulation,and invasive methods using microelectrode arrays.The non-invasive techniques discussed include transcranial magnetic stimulation,transcranial direct current stimulation,transcranial alternating current stimulation,transcutaneous electrical acupoint stimulation,and time interference stimulation for activating deep targets.Invasive stimulation methods,which are ideal for studying the pathogenesis of neurological diseases,tend to cause greater trauma and have been less researched in the context of cognitive function regulation.Non-invasive methods,particularly newer transcranial stimulation techniques,are gentler and more appropriate for regulating cognitive functions in the general population.These include transcutaneous acupoint electrical stimulation using acupoints and time interference methods for activating deep targets.This paper also discusses current technical challenges and potential future breakthroughs in neuromodulation technology.It is recommended that neuromodulation techniques be combined with neural detection methods to better assess their effects and improve the accuracy of non-invasive neuromodulation.Additionally,researching closed-loop feedback neuromodulation methods is identified as a promising direction for future development.展开更多
The roots of O. fragrans are also a valuable resource in addition to its flowers and fruits. In this study, the HPLC-MS/MS method used for analyzing the chemical constituents in O. fragrans roots extract was developed...The roots of O. fragrans are also a valuable resource in addition to its flowers and fruits. In this study, the HPLC-MS/MS method used for analyzing the chemical constituents in O. fragrans roots extract was developed, which showed high sensitivity for both qualitative and quantitative analyses. Thirty-two compounds were first discovered in O. fragrans roots, one compound of which was reported for the first time. The simultaneous determination method for acteoside, isoacteoside, oleuropein and phillyrin was validated to be sensitive and accurate. Then it was applied to determine the content of bioactive components in O. fragrans roots from different cultivars. The content of oleuropein and phillyrin in the twelve batches was relatively stable, while the content of acteoside and isoacteoside varied greatly.Moreover, the therapeutic material basis and mechanism of O. fragrans roots exerting its traditional pharmacodynamics were analyzed by network pharmacology. The results showed that O. fragrans roots might be effective for the treatment of inflammation, cardiovascular diseases, cancer, and rheumatoid arthritis, which is consistent with the traditional pharmacodynamics of O. fragrans roots. This work can provide an analytical method for the comprehensive development of O. fragrans roots.展开更多
The fruits of leguminous plants Cercis Chinensis Bunge are still overlooked although they have been reported to be antioxidative because of the limited information on the phytochemicals of C.chinensis fruits.A simple,...The fruits of leguminous plants Cercis Chinensis Bunge are still overlooked although they have been reported to be antioxidative because of the limited information on the phytochemicals of C.chinensis fruits.A simple,rapid and sensitive HPLC-MS/MS method was developed for the identification and quantitation of the major bioactive components in C.chinensis fruits.Eighteen polyphenols were identified,which are first reported in C.chinensis fruits.Moreover,ten components were simultaneously quantified.The validated quantitative method was proved to be sensitive,reproducible and accurate.Then,it was applied to analyze batches of C.chinensis fruits from different phytomorph and areas.The principal components analysis(PCA)realized visualization and reduction of data set dimension while the hierarchical cluster analysis(HCA)indicated that the content of phenolic acids or all ten components might be used to differentiate C.chinensis fruits of different phytomorph.展开更多
Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin （NHFS） was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200...Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin （NHFS） was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No. 16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein （KU： keratinase unit）. Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40℃ to 55℃. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development.展开更多
The physics package of a chip-scale atomic clock （CSAC） has been successfully realized by integrating vertical cavity surface emitting laser （VCSEL）, neutral density （ND） filter, λ/4 wave plate, 87Rb vapor cell...The physics package of a chip-scale atomic clock （CSAC） has been successfully realized by integrating vertical cavity surface emitting laser （VCSEL）, neutral density （ND） filter, λ/4 wave plate, 87Rb vapor cell, photodiode （PD）, and magnetic coil into a cuboid metal package with a volume of about 2.8 cm3. In this physics package, the critical component, 87Rb vapor cell, is batch-fabricated based on MEMS technology and in-situ chemical reaction method. Pt heater and thermistors are integrated in the physics package. A PTFE pillar is used to support the optical elements in the physics package, in order to reduce the power dissipation. The optical absorption spectrum of 87Rb D1 line and the microwave frequency correction signal are successfully observed while connecting the package with the servo circuit system. Using the above mentioned packaging solution, a CSAC with short-term frequency stability of about 7 × 10^-10τ-1/2 has been successfully achieved, which demonstrates that this physics package would become one promising solution for the CSAC.展开更多
The use of magnetic nanoparticle(MNP)-labeled immunochromatography test strips(ICTSs) is very important for point-ofcare testing(POCT). However, common diagnostic methods cannot accurately analyze the weak magnetic si...The use of magnetic nanoparticle(MNP)-labeled immunochromatography test strips(ICTSs) is very important for point-ofcare testing(POCT). However, common diagnostic methods cannot accurately analyze the weak magnetic signal from ICTSs, limiting the applications of POCT. In this study, an ultrasensitive multiplex biosensor was designed to overcome the limitations of capturing and normalization of the weak magnetic signal from MNPs on ICTSs. A machine learning model for sandwich assays was constructed and used to classify weakly positive and negative samples, which significantly enhanced the specificity and sensitivity. The potential clinical application was evaluated by detecting 50 human chorionic gonadotropin(HCG) samples and 59 myocardial infarction serum samples. The quantitative range for HCG was 1–1000 mIU mL^(-1) and the ideal detection limit was 0.014 mIU mL^(-1), which was well below the clinical threshold. Quantitative detection results of multiplex cardiac markers showed good linear correlations with standard values. The proposed multiplex assay can be readily adapted for identifying other biomolecules and also be used in other applications such as environmental monitoring, food analysis, and national security.展开更多
Nanowires and nanotubes of diverse material compositions,properties and/or functions have been produced or fabricated through various bottom-up or top-down approaches.These nanowires or nanotubes have also been utiliz...Nanowires and nanotubes of diverse material compositions,properties and/or functions have been produced or fabricated through various bottom-up or top-down approaches.These nanowires or nanotubes have also been utilized as potential building blocks for functional nanodevices.The key for the integration of those nanowire or nanotube based devices is to assemble these one dimensional nanomaterials to specific locations using techniques that are highly controllable and scalable.Ideally such techniques should enable assembly of highly uniform nanowire/nanotube arrays with precise control of density,location,dimension or even material types of nanowires/nanotubes.Numerous assembly techniques are being developed that can quickly align and assemble large quantities of one type or multiple types of nanowires through parallel processes,including flow-assisted alignment,Langmuir-Blodgett assembly,bubble-blown technique,electric/magnetic-field directed assembly,contact/roll printing,knocking-down,etc..With these assembling techniques,applications of nanowire/nanotube based devices such as flexible electronics and sensors have been demonstrated.This paper delivers an overall review of directed nanowire/nanotube assembling approaches and analyzes advantages and limitations of each method.The future research directions have also been discussed.展开更多
Tumor-derived exosomes are actively involved in cancer progression and metastasis and have emerged as a promising marker for cancer diagnosis in liquid biopsy.Because of their nanoscale size,complex biogenesis,and met...Tumor-derived exosomes are actively involved in cancer progression and metastasis and have emerged as a promising marker for cancer diagnosis in liquid biopsy.Because of their nanoscale size,complex biogenesis,and methodological limitations related to exosome isolation and detection,advancements in their analysis remain slow.Microfluidic technology offers a better analytic approach compared with conventional methods.Here,we developed a bead-based microarray for exosome isolation and multiplexed tumor marker detection.Using this method,exosomes are isolated by binding to antibodies on the bead surface,and tumor markers on the exosomes are detected through quantum dot(QD)probes.The beads are then uniformly trapped and queued among micropillars in the chip.This design benefits fluorescence observation by dispersing the signals into every single bead,thereby avoiding optical interference and enabling more accurate test results.We analyzed exosomes in the cell culture supernatant of lung cancer and endothelial cell lines,and different lung cancer markers labeled with three QD probes were used to conduct multiplexed detection of exosome surface protein markers.Lung cancer-derived samples showed much higher(~sixfold-tenfold)fluorescence intensity than endothelial cell samples,and different types of lung cancer samples showed distinctive marker expression levels.Additionally,using the chip to detect clinical plasma samples from cancer patients showed good diagnostic power and revealed a well consistency with conventional tests for serological markers.These results provide insight into a promising method for exosome tumor marker detection and early-stage cancer diagnosis.展开更多
Exosomes are now raising focus as a prospective biomarker for cancer diagnostics and prognosis owing to its unique bio-origin and composition.Exosomes take part in cellular communication and receptor mediation and tra...Exosomes are now raising focus as a prospective biomarker for cancer diagnostics and prognosis owing to its unique bio-origin and composition.Exosomes take part in cellular communication and receptor mediation and transfer their cargos(e.g.,proteins,m RNA and DNA).Quantitative analysis of tumor-related nucleic acid mutations can be a potential method to cancer diagnosis and prognosis in early stages.Here we present an integrated microfluidic system for exosome on-chip isolation and lung cancer RNA analysis through droplet digital PCR(dd PCR).Gradient dilution experiments show great linearity over a large concentration range with R^(2)=0.9998.Utilizing the system,four cell lines and two mutation targets were parallelly detected for mutation analysis.The experiments demonstrated mutation heterogeneity and the results were agree with cell researches.These results proved our integrated microfluidic system as a promising means for early cancer diagnosis and prognosis in the era of liquid biopsy.展开更多
Polarimetric imaging enhances the ability to distinguish objects from a bright background by detecting their particular polarization status,which offers another degree of freedom in infrared remote sensing.However,to ...Polarimetric imaging enhances the ability to distinguish objects from a bright background by detecting their particular polarization status,which offers another degree of freedom in infrared remote sensing.However,to scale up by monolithically integrating grating-based polarizers onto a focal plane array(FPA)of infrared detectors,fundamental technical obstacles must be overcome,including reductions of the extinction ratio by the misalignment between the polarizer and the detector,grating line width fluctuations,the line edge roughness,etc.This paper reports the authors’latest achievements in overcoming those problems by solving key technical issues regarding the integration of large-scale polarizers onto the chips of FPAs with individual indium gallium arsenide/indium phosphide(In Ga As/In P)sensors as the basic building blocks.Polarimetric and photovoltaic chips with divisions of the focal plane of 540×4 pixels and 320×256 superpixels have been successfully manufactured.Polarimetric imaging with enhanced contrast has been demonstrated.The progress made in this work has opened up a broad avenue toward industrialization of high quality polarimetric imaging in infrared wavelengths.展开更多
A novel ultra-low-power readout integrated circuit(ROIC) for 1 024×1 024 ultraviolet(UV) AlGaN focal plane arrays(FPA) with 18 μm-pitch was presented. In order to optimize power consumption for UVFPA readout cir...A novel ultra-low-power readout integrated circuit(ROIC) for 1 024×1 024 ultraviolet(UV) AlGaN focal plane arrays(FPA) with 18 μm-pitch was presented. In order to optimize power consumption for UVFPA readout circuit these methods were adopted, which including single-terminal amplifier under subthreshold region as CTIA amplifier, common current source load for source follow(SF) buffer in column pixels and level shift circuits, and time-sharing tail current source for column buffer. The smallest operational current of CTIA in pixel unit is only 8.5 nA with 3.3 V power supply by using single-terminal amplifier. The ROIC has been fabricated in SMIC 0.18 μm 1P6M mixed signal process and also achieved better performances with the novel design of bias current adjustable. Furthermore, the overall power consumption of the chip is 67.3 mW at 2 MHz in 8-outputs mode by the above methods according to the experimental results.展开更多
The Schottky photodetector was fabricated on GaN epilayers grown by metalorganic chemical vapour deposition （MOCVD）. The spectral response of the Schottky photodetector was characterized. A new model is proposed to ...The Schottky photodetector was fabricated on GaN epilayers grown by metalorganic chemical vapour deposition （MOCVD）. The spectral response of the Schottky photodetector was characterized. A new model is proposed to interpret the characteristic of the spectral response curve of the Schottky photodetectors by introducing a penetrating distance of an incident light at a certain wavelength in the current continuity equation and the interface recombination at the metal-semiconductor rectifying contact. The expressions for the spectral response of the Schottky photodetector are deduced and used successfully to fit the experimental data.展开更多
Tumor heterogeneity plays a critical role in the determination of appropriate anticancer therapy.As cir-culating tumor cells(CTCs)contain all tumor-related information,the genetic changes on CTCs could help us choose ...Tumor heterogeneity plays a critical role in the determination of appropriate anticancer therapy.As cir-culating tumor cells(CTCs)contain all tumor-related information,the genetic changes on CTCs could help us choose the appropriate treatments for different patients.Single-base mutations are very common in tumor genetic changes which may result in drug resistance.Here,we introduce a single-cell mutation de-tection platform based on droplet microfluidics.This platform integrates cell capsulation,cell lysis,poly-merase chain reaction(PCR)and the observation process.The droplets’generation speed is over 6000 per minute and more than 600 cells could be encapsulated in one second.To verify the performance of our platform in practical use,we performed the mutation analysis of 4 kinds of cells with our platform and noted that the genetic status of each single cell was clearly discriminated.Moreover,these results agreed with those from direct sequencing.Compared with other forms of single-cell mutation detection techniques,our platform has high throughput,short experimental time and less experimental operations.展开更多
Photo-responsive azobenzene （ABZ） derivatives with different end groups （R） as photoswitchable molecules were employed to construct self-assembled monolayers （SAMs） on silicon substrate by using 3-glycidoxypropy...Photo-responsive azobenzene （ABZ） derivatives with different end groups （R） as photoswitchable molecules were employed to construct self-assembled monolayers （SAMs） on silicon substrate by using 3-glycidoxypropyltrimethoxysilane （GPTS） as the bridging molecules. The assembly process was optimized by changing various parameters, including the type and concentration of ABZ derivatives, reaction time, etc. The obtained SAMs were fully characterized and evaluated using UV spectroscopy, atomic force microscope （AFM）, elllipsometer, static contact angle and X-ray photoelectron spectroscopy （XPS）. It is found that the end group property of azobenzene derivatives is critical to the obtained SAMs＇ photoresponsive properties. Compared with hydrophobic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-CF3）, the hydrophilic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-COOH） show excellent reversible photoswitching performance with a large contact angle change of 35° under oDtimized process, and the SAMs are removable bv thermal treatment at 240 ℃ in air for onlv 5 min.展开更多
Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China,and its components,which include ultrafine particles(UFPs),volatile organic compounds(VOCs),and other reactive gases,su...Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China,and its components,which include ultrafine particles(UFPs),volatile organic compounds(VOCs),and other reactive gases,such as NH3and NOx,are the most harmful to human health.China has released various regulations and standards to address pollution from mobile and stationary sources.Thus,it is urgent to develop online monitoring technology for atmospheric pollution source emissions.This study provides an overview of the main progress in mobile and stationary source monitoring technology in China and describes the comprehensive application of some typical instruments in vital areas in recent years.These instruments have been applied to monitor emissions from motor vehicles,ships,airports,the chemical industry,and electric power generation.Not only has the level of atmospheric environment monitoring technology and equipment been improving,but relevant regulations and standards have also been constantly updated.Meanwhile,the developed instruments can provide scientific assistance for the successful implementation of regulations.According to the potential problem areas in atmospheric pollution in China,some research hotspots and future trends of atmospheric online monitoring technology are summarized.Furthermore,more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.展开更多
A simple,convenient,and highly sensitive bio-interface for graphene field-effect transistors(GFETs) based on multifunctional nano-denatured bovine serum albumin(nano-dBSA) functionalization was developed to target can...A simple,convenient,and highly sensitive bio-interface for graphene field-effect transistors(GFETs) based on multifunctional nano-denatured bovine serum albumin(nano-dBSA) functionalization was developed to target cancer bio-markers.The novel graphene–protein bioelectronic interface was constructed by heating to denature native BSA on the graphene substrate surface.The formed nano-d BSA film served as the cross-linker to immobilize monoclonal antibody against car-cinoembryonic antigen(anti-CEA mAb) on the graphene channel activated by EDC and Sulfo-NHS.The nano-dBSA film worked as a self-protecting layer of graphene to prevent surface contamination by lithographic processing.The improved GFETbiosensor exhibited good specificity and high sensitivity toward the target at an ultralow concentration of 337.58 fg mL-1.The electrical detection of the binding of CEA followed the Hill model for ligand–receptor interaction,indicating the negative binding cooperativity between CEA and anti-CEA mAb with a dissociation constant of 6.82×10-10M.The multifunctional nano-dBSA functionalization can confer a new function to graphene-like 2D nanomaterials and provide a promising bio-functionalization method for clinical application in biosensing,nanomedicine,and drug delivery.展开更多
文摘We have presented a three dimensional optical protein chip that fulfills the demanding for point-of-care diagnostics in terms of ease-of-use (one step assay), miniaturization (5 μl). The artful combination of magnetic nanoparticles on chip and total internal reflection imaging (TIRI) technology permits the sensitive and rapid detection of hs-CRP (high-sensitivity C-reactive protein). The whole test was complete within 10 min using “all in one step” assay with a limit of detection of 0.1 ng/mL hs-CRP. The measuring range for hs-CRP could be extended to 10 ng/mL. The chip can also be used to detect more parameters in blood samples.
基金sponsored by the National Key R&D Program of China(Grant Nos.2022YFC2402500 and 2022YFB3205602)the National Natural Science Foundation of China(Grant Nos.62121003,T2293730,T2293731,62333020,62171434,62471291)+2 种基金the Major Program of Scientific and Technical Innovation 2030(Grant No.2021ZD02016030)the Joint Foundation Program of the Chinese Academy of Sciences(Grant No.8091A170201)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.PTYQ2024BJ0009).
文摘Anesthesia plays a crucial role in regulating physiological states during medical procedures,but its effects on neural activity remain incompletely understood,particularly at the prefrontal cortical level.The prefrontal cortex is essential for various cognitive and motor functions,yet high-spatiotemporal-resolution electrodes at the cellular level remain challenging to develop,which has hindered the acquisition of detailed electrophysiological data from anesthetized subjects.Here,we design a 16-channel silicon-based microelectrode array(MEA),which,after modification with platinum black nanoparticles,exhibits significantly reduced impedance(22.5 kΩ)and increased phase(−33.5°),enhancing its electrical performance and electrophysiological signal detection capabilities.Using this modified MEA,we have recorded cellular-level neural activity during the recovery process of a rhesus macaque following prolonged anesthesia.Over a 660 s period,we observed a gradual increase in the neuronal firing rate in the F7 area,along with distinctive patterns in local field potentials across different frequency bands.Notably,power in the δ and θ bands increased continuously during recovery,highlighting their potential role in the transition from anesthesia to wakefulness.Our findings provide new insights into the dynamic recovery process of cortical neurons and offer a powerful tool for high-spatiotemporal-resolution neural monitoring in nonhuman primates.
基金support from the National Natural Science Foundation of China(Grant Nos.62331025 and 62121003).
文摘In fluorescence flow cytometry,spectral overlap among multiple fluorescent labels cannot be avoided,and thus detected fluorescent intensities need to be compensated.Although fluorescent compensation in flow cytometry has been widely used for many years,it still lacks quantitative evaluations to validate its effectiveness.Using a home-developed nine-color fluorescence flow cytometer,this study first obtains calibration curves by assaying gradient concentrations of nine different fluorochromes individually,with the fluorescent intensities of the highest concentrations of each fluorochrome being used to obtain a spillover matrix.Mixed fluorescent solutions are analyzed by flow cytometry in which the obtained fluorescent intensities are compensated by the spillover matrix,translated to specific concentrations based on calibration curve and compared with nominal values.Three mixed solutions of Brilliant Violet 650 and Brilliant Violet 711,of Alexa Fluor 488 and PE,and of Pacific Orange,Alexa Fluor 488,and PE are tested,with fluorescent compensation being observed to reduce excessive signals due to spectral overlap.Specifically,concentration deviations(before vs after compensation)in comparison with nominal values for Brilliant Violet 711 and Alexa Fluor 488 are quantified as 40.6%vs 14.9%and 6.7%vs 1.9%,respectively.The results presented here provide a quantitative reference for fluorescent compensation that can be used to effectively address the issue of spectral overlap in fluorescence flow cytometry.
基金supported by STI 2030-Major Projects,No.2021ZD0201603(to JL)the Joint Foundation Program of the Chinese Academy of Sciences,No.8091A170201(to JL)+1 种基金the National Natural Science Foundation of China,Nos.T2293730(to XC),T2293731(to XC),T2293734(to XC),62471291(to YW),62121003(to XC),61960206012(to XC),62333020(to XC),and 62171434(to XC)the National Key Research and Development Program of China,Nos.2022YFC2402501(to XC),2022YFB3205602(to XC).
文摘Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize electrical stimulation to directly or indirectly target specific brain regions,modulating neural activity and influencing broader brain networks,thereby regulating cognitive function.Regulating cognitive function involves an understanding of aspects such as perception,learning and memory,attention,spatial cognition,and physical function.To enhance the application of cognitive regulation in the general population,this paper reviews recent publications from the Web of Science to assess the advancements and challenges of invasive and non-invasive stimulation methods in modulating cognitive functions.This review covers various neuromodulation techniques for cognitive intervention,including deep brain stimulation,vagus nerve stimulation,and invasive methods using microelectrode arrays.The non-invasive techniques discussed include transcranial magnetic stimulation,transcranial direct current stimulation,transcranial alternating current stimulation,transcutaneous electrical acupoint stimulation,and time interference stimulation for activating deep targets.Invasive stimulation methods,which are ideal for studying the pathogenesis of neurological diseases,tend to cause greater trauma and have been less researched in the context of cognitive function regulation.Non-invasive methods,particularly newer transcranial stimulation techniques,are gentler and more appropriate for regulating cognitive functions in the general population.These include transcutaneous acupoint electrical stimulation using acupoints and time interference methods for activating deep targets.This paper also discusses current technical challenges and potential future breakthroughs in neuromodulation technology.It is recommended that neuromodulation techniques be combined with neural detection methods to better assess their effects and improve the accuracy of non-invasive neuromodulation.Additionally,researching closed-loop feedback neuromodulation methods is identified as a promising direction for future development.
基金supported by the National Natural Science Foundation of China(Grant Nos.81872828 and 81573384)the Large-scale Instrument and Equipment Sharing Foundation of Wuhan University(LF20191065)。
文摘The roots of O. fragrans are also a valuable resource in addition to its flowers and fruits. In this study, the HPLC-MS/MS method used for analyzing the chemical constituents in O. fragrans roots extract was developed, which showed high sensitivity for both qualitative and quantitative analyses. Thirty-two compounds were first discovered in O. fragrans roots, one compound of which was reported for the first time. The simultaneous determination method for acteoside, isoacteoside, oleuropein and phillyrin was validated to be sensitive and accurate. Then it was applied to determine the content of bioactive components in O. fragrans roots from different cultivars. The content of oleuropein and phillyrin in the twelve batches was relatively stable, while the content of acteoside and isoacteoside varied greatly.Moreover, the therapeutic material basis and mechanism of O. fragrans roots exerting its traditional pharmacodynamics were analyzed by network pharmacology. The results showed that O. fragrans roots might be effective for the treatment of inflammation, cardiovascular diseases, cancer, and rheumatoid arthritis, which is consistent with the traditional pharmacodynamics of O. fragrans roots. This work can provide an analytical method for the comprehensive development of O. fragrans roots.
基金supported by the National Natural Science Foundation of China(Grant Nos.82073808,81872828,and 81573384)。
文摘The fruits of leguminous plants Cercis Chinensis Bunge are still overlooked although they have been reported to be antioxidative because of the limited information on the phytochemicals of C.chinensis fruits.A simple,rapid and sensitive HPLC-MS/MS method was developed for the identification and quantitation of the major bioactive components in C.chinensis fruits.Eighteen polyphenols were identified,which are first reported in C.chinensis fruits.Moreover,ten components were simultaneously quantified.The validated quantitative method was proved to be sensitive,reproducible and accurate.Then,it was applied to analyze batches of C.chinensis fruits from different phytomorph and areas.The principal components analysis(PCA)realized visualization and reduction of data set dimension while the hierarchical cluster analysis(HCA)indicated that the content of phenolic acids or all ten components might be used to differentiate C.chinensis fruits of different phytomorph.
文摘Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin （NHFS） was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No. 16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein （KU： keratinase unit）. Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40℃ to 55℃. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development.
基金supported by the Knowledge Innovation Project of Chinese Academy of Sciences(Grant No.KGCX2-YW-143)
文摘The physics package of a chip-scale atomic clock （CSAC） has been successfully realized by integrating vertical cavity surface emitting laser （VCSEL）, neutral density （ND） filter, λ/4 wave plate, 87Rb vapor cell, photodiode （PD）, and magnetic coil into a cuboid metal package with a volume of about 2.8 cm3. In this physics package, the critical component, 87Rb vapor cell, is batch-fabricated based on MEMS technology and in-situ chemical reaction method. Pt heater and thermistors are integrated in the physics package. A PTFE pillar is used to support the optical elements in the physics package, in order to reduce the power dissipation. The optical absorption spectrum of 87Rb D1 line and the microwave frequency correction signal are successfully observed while connecting the package with the servo circuit system. Using the above mentioned packaging solution, a CSAC with short-term frequency stability of about 7 × 10^-10τ-1/2 has been successfully achieved, which demonstrates that this physics package would become one promising solution for the CSAC.
基金support by the National Key Research and Development Program of China (Grant Nos. 2017FYA0205301, and 2017FYA0205303)the National Natural Science Foundation of China (Grant Nos. 81571835 and 81672247)+3 种基金National Key Research and Development Program of China (No. 2017YFA0205303)National Key Basic Research Program (973 Project) (No. 2015CB931802)"13th Five-Year Plan" Science and Technology Project of Jilin Province Education Department (No. JJKH20170410K)Shanghai Science and Technology Fund (No. 15DZ2252000)
文摘The use of magnetic nanoparticle(MNP)-labeled immunochromatography test strips(ICTSs) is very important for point-ofcare testing(POCT). However, common diagnostic methods cannot accurately analyze the weak magnetic signal from ICTSs, limiting the applications of POCT. In this study, an ultrasensitive multiplex biosensor was designed to overcome the limitations of capturing and normalization of the weak magnetic signal from MNPs on ICTSs. A machine learning model for sandwich assays was constructed and used to classify weakly positive and negative samples, which significantly enhanced the specificity and sensitivity. The potential clinical application was evaluated by detecting 50 human chorionic gonadotropin(HCG) samples and 59 myocardial infarction serum samples. The quantitative range for HCG was 1–1000 mIU mL^(-1) and the ideal detection limit was 0.014 mIU mL^(-1), which was well below the clinical threshold. Quantitative detection results of multiplex cardiac markers showed good linear correlations with standard values. The proposed multiplex assay can be readily adapted for identifying other biomolecules and also be used in other applications such as environmental monitoring, food analysis, and national security.
基金the financial support from Natural Science and Engineering Research Council of Canada (NSERC)funding from Science and Technology Commission of Shanghai Municipality (No.11PJ1403500)+1 种基金the Open Project Program of State Key Laboratory of Industrial Control Technology (No.ICT1113)Innovation Program of Shanghai Municipal Education Commission (No.12YZ022)
文摘Nanowires and nanotubes of diverse material compositions,properties and/or functions have been produced or fabricated through various bottom-up or top-down approaches.These nanowires or nanotubes have also been utilized as potential building blocks for functional nanodevices.The key for the integration of those nanowire or nanotube based devices is to assemble these one dimensional nanomaterials to specific locations using techniques that are highly controllable and scalable.Ideally such techniques should enable assembly of highly uniform nanowire/nanotube arrays with precise control of density,location,dimension or even material types of nanowires/nanotubes.Numerous assembly techniques are being developed that can quickly align and assemble large quantities of one type or multiple types of nanowires through parallel processes,including flow-assisted alignment,Langmuir-Blodgett assembly,bubble-blown technique,electric/magnetic-field directed assembly,contact/roll printing,knocking-down,etc..With these assembling techniques,applications of nanowire/nanotube based devices such as flexible electronics and sensors have been demonstrated.This paper delivers an overall review of directed nanowire/nanotube assembling approaches and analyzes advantages and limitations of each method.The future research directions have also been discussed.
基金supported by Grants from National Key Research and Development Program of China(Nos.2018YFA0108202 and 2017YFA0205300)National Science Foundation of China(Nos.61571429,61571077,61801464,and 61801465)+1 种基金the STS Project of the Chinese Academy of Sciences(No.KFJ-STS-SCYD-120)the Science and Technology Commission of Shanghai Municipality(Nos.16410711800 and 4391901900).
文摘Tumor-derived exosomes are actively involved in cancer progression and metastasis and have emerged as a promising marker for cancer diagnosis in liquid biopsy.Because of their nanoscale size,complex biogenesis,and methodological limitations related to exosome isolation and detection,advancements in their analysis remain slow.Microfluidic technology offers a better analytic approach compared with conventional methods.Here,we developed a bead-based microarray for exosome isolation and multiplexed tumor marker detection.Using this method,exosomes are isolated by binding to antibodies on the bead surface,and tumor markers on the exosomes are detected through quantum dot(QD)probes.The beads are then uniformly trapped and queued among micropillars in the chip.This design benefits fluorescence observation by dispersing the signals into every single bead,thereby avoiding optical interference and enabling more accurate test results.We analyzed exosomes in the cell culture supernatant of lung cancer and endothelial cell lines,and different lung cancer markers labeled with three QD probes were used to conduct multiplexed detection of exosome surface protein markers.Lung cancer-derived samples showed much higher(~sixfold-tenfold)fluorescence intensity than endothelial cell samples,and different types of lung cancer samples showed distinctive marker expression levels.Additionally,using the chip to detect clinical plasma samples from cancer patients showed good diagnostic power and revealed a well consistency with conventional tests for serological markers.These results provide insight into a promising method for exosome tumor marker detection and early-stage cancer diagnosis.
基金National Natural Science Foundation of China(Nos.61971410,and 62001458)Shanghai Sailing Program(No.20YF1457100)。
文摘Exosomes are now raising focus as a prospective biomarker for cancer diagnostics and prognosis owing to its unique bio-origin and composition.Exosomes take part in cellular communication and receptor mediation and transfer their cargos(e.g.,proteins,m RNA and DNA).Quantitative analysis of tumor-related nucleic acid mutations can be a potential method to cancer diagnosis and prognosis in early stages.Here we present an integrated microfluidic system for exosome on-chip isolation and lung cancer RNA analysis through droplet digital PCR(dd PCR).Gradient dilution experiments show great linearity over a large concentration range with R^(2)=0.9998.Utilizing the system,four cell lines and two mutation targets were parallelly detected for mutation analysis.The experiments demonstrated mutation heterogeneity and the results were agree with cell researches.These results proved our integrated microfluidic system as a promising means for early cancer diagnosis and prognosis in the era of liquid biopsy.
基金financially supported by the following projects:Open project of SITP(Project Number:IIMDKFJJ-18-09)National Natural Science Foundation of China(Project Number:61927820)+2 种基金The STCSM2019-11-20 funding(Project Number:19142202700)National Natural Science Foundation of China(Project Number:NSF No.U1732104)Zhejiang Lab’s International Talent Fund for Young Professionals。
文摘Polarimetric imaging enhances the ability to distinguish objects from a bright background by detecting their particular polarization status,which offers another degree of freedom in infrared remote sensing.However,to scale up by monolithically integrating grating-based polarizers onto a focal plane array(FPA)of infrared detectors,fundamental technical obstacles must be overcome,including reductions of the extinction ratio by the misalignment between the polarizer and the detector,grating line width fluctuations,the line edge roughness,etc.This paper reports the authors’latest achievements in overcoming those problems by solving key technical issues regarding the integration of large-scale polarizers onto the chips of FPAs with individual indium gallium arsenide/indium phosphide(In Ga As/In P)sensors as the basic building blocks.Polarimetric and photovoltaic chips with divisions of the focal plane of 540×4 pixels and 320×256 superpixels have been successfully manufactured.Polarimetric imaging with enhanced contrast has been demonstrated.The progress made in this work has opened up a broad avenue toward industrialization of high quality polarimetric imaging in infrared wavelengths.
文摘A novel ultra-low-power readout integrated circuit(ROIC) for 1 024×1 024 ultraviolet(UV) AlGaN focal plane arrays(FPA) with 18 μm-pitch was presented. In order to optimize power consumption for UVFPA readout circuit these methods were adopted, which including single-terminal amplifier under subthreshold region as CTIA amplifier, common current source load for source follow(SF) buffer in column pixels and level shift circuits, and time-sharing tail current source for column buffer. The smallest operational current of CTIA in pixel unit is only 8.5 nA with 3.3 V power supply by using single-terminal amplifier. The ROIC has been fabricated in SMIC 0.18 μm 1P6M mixed signal process and also achieved better performances with the novel design of bias current adjustable. Furthermore, the overall power consumption of the chip is 67.3 mW at 2 MHz in 8-outputs mode by the above methods according to the experimental results.
文摘The Schottky photodetector was fabricated on GaN epilayers grown by metalorganic chemical vapour deposition （MOCVD）. The spectral response of the Schottky photodetector was characterized. A new model is proposed to interpret the characteristic of the spectral response curve of the Schottky photodetectors by introducing a penetrating distance of an incident light at a certain wavelength in the current continuity equation and the interface recombination at the metal-semiconductor rectifying contact. The expressions for the spectral response of the Schottky photodetector are deduced and used successfully to fit the experimental data.
基金supported by the National Key Research and Development Program of China(No.2017YFA0205300)National Natural Science Foundation of China(Nos.61971410,61701171,61801464,61801465 and 62001458)+1 种基金Shanghai Sailing Program(No.20YF1457100),Shanghai Engineer&Technology Research Center of Internet of Things for Respiratory Medicine(No.20DZ2254400)the Science and Technology Commission of Shanghai Munic-ipality(No.19511104200).
文摘Tumor heterogeneity plays a critical role in the determination of appropriate anticancer therapy.As cir-culating tumor cells(CTCs)contain all tumor-related information,the genetic changes on CTCs could help us choose the appropriate treatments for different patients.Single-base mutations are very common in tumor genetic changes which may result in drug resistance.Here,we introduce a single-cell mutation de-tection platform based on droplet microfluidics.This platform integrates cell capsulation,cell lysis,poly-merase chain reaction(PCR)and the observation process.The droplets’generation speed is over 6000 per minute and more than 600 cells could be encapsulated in one second.To verify the performance of our platform in practical use,we performed the mutation analysis of 4 kinds of cells with our platform and noted that the genetic status of each single cell was clearly discriminated.Moreover,these results agreed with those from direct sequencing.Compared with other forms of single-cell mutation detection techniques,our platform has high throughput,short experimental time and less experimental operations.
基金financially supported by The Dow Chemical Company
文摘Photo-responsive azobenzene （ABZ） derivatives with different end groups （R） as photoswitchable molecules were employed to construct self-assembled monolayers （SAMs） on silicon substrate by using 3-glycidoxypropyltrimethoxysilane （GPTS） as the bridging molecules. The assembly process was optimized by changing various parameters, including the type and concentration of ABZ derivatives, reaction time, etc. The obtained SAMs were fully characterized and evaluated using UV spectroscopy, atomic force microscope （AFM）, elllipsometer, static contact angle and X-ray photoelectron spectroscopy （XPS）. It is found that the end group property of azobenzene derivatives is critical to the obtained SAMs＇ photoresponsive properties. Compared with hydrophobic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-CF3）, the hydrophilic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-COOH） show excellent reversible photoswitching performance with a large contact angle change of 35° under oDtimized process, and the SAMs are removable bv thermal treatment at 240 ℃ in air for onlv 5 min.
基金supported by the National Key Research and Development Program of China(Nos.2016YFC0201000 and 2016YFC0201100)the Plan for Anhui Major Provincial Science&Technology Project(Nos.202203a07020004 and 202003a07020005)+1 种基金the National Natural Science Foundation of China(Nos.U2133212 and 42005108)the Science and Technological Fund of Anhui Province for Outstanding Youth(No.1808085J19)。
文摘Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China,and its components,which include ultrafine particles(UFPs),volatile organic compounds(VOCs),and other reactive gases,such as NH3and NOx,are the most harmful to human health.China has released various regulations and standards to address pollution from mobile and stationary sources.Thus,it is urgent to develop online monitoring technology for atmospheric pollution source emissions.This study provides an overview of the main progress in mobile and stationary source monitoring technology in China and describes the comprehensive application of some typical instruments in vital areas in recent years.These instruments have been applied to monitor emissions from motor vehicles,ships,airports,the chemical industry,and electric power generation.Not only has the level of atmospheric environment monitoring technology and equipment been improving,but relevant regulations and standards have also been constantly updated.Meanwhile,the developed instruments can provide scientific assistance for the successful implementation of regulations.According to the potential problem areas in atmospheric pollution in China,some research hotspots and future trends of atmospheric online monitoring technology are summarized.Furthermore,more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.
基金the support of grants from the National Key R&D Program of China(Nos.2018YFA0108202 and 2017YFA0205300)the National Natural Science Foundation of China(Nos.61571429,61801464,61801465,and 81471748)+1 种基金the STS Project of the Chinese Academy of Sciences(NO.KFJ-STS-SCYD-120)the Science and Technology Commission of Shanghai Municipality(Nos.16410711800 and 14391901900)
文摘A simple,convenient,and highly sensitive bio-interface for graphene field-effect transistors(GFETs) based on multifunctional nano-denatured bovine serum albumin(nano-dBSA) functionalization was developed to target cancer bio-markers.The novel graphene–protein bioelectronic interface was constructed by heating to denature native BSA on the graphene substrate surface.The formed nano-d BSA film served as the cross-linker to immobilize monoclonal antibody against car-cinoembryonic antigen(anti-CEA mAb) on the graphene channel activated by EDC and Sulfo-NHS.The nano-dBSA film worked as a self-protecting layer of graphene to prevent surface contamination by lithographic processing.The improved GFETbiosensor exhibited good specificity and high sensitivity toward the target at an ultralow concentration of 337.58 fg mL-1.The electrical detection of the binding of CEA followed the Hill model for ligand–receptor interaction,indicating the negative binding cooperativity between CEA and anti-CEA mAb with a dissociation constant of 6.82×10-10M.The multifunctional nano-dBSA functionalization can confer a new function to graphene-like 2D nanomaterials and provide a promising bio-functionalization method for clinical application in biosensing,nanomedicine,and drug delivery.
