Ferroptosis has exhibited great potential in therapies and intracellular reducing agents of sulfur species(RSSs) in the thiol-dependent redox systems are crucial in ferroptosis.This makes the simultaneous detection of...Ferroptosis has exhibited great potential in therapies and intracellular reducing agents of sulfur species(RSSs) in the thiol-dependent redox systems are crucial in ferroptosis.This makes the simultaneous detection of multiple RSSs significant for evaluating ferroptosis therapy.However,the traditional techniques,including fluorescent(FL) imaging and electrospray ionization-based mass spectrometry(MS) detection,cannot achieve the discrimination of different RSSs.Herein,simultaneous MS detection of multiple RSSs,including cysteine(Cys),homocysteine(Hcy),glutathione(GSH) and hydrogen sulfide(H_(2)S),was obtained upon enhancing ionization efficiency by a fluorescent probe(NBD-O-1).Based on the interaction between NBD-O-1 and RSSs,the complex of RSSs with a fragment of NBD-O-1 can be generated,which can be easily ionized for MS detection in the negative mode.Therefore,the intracellular RSSs can be well detected upon the incubation of He La cells with the probe of NBD-O-1,exhibiting the total RSS levels by the FL imaging and further providing expression of each RSS by enhanced MS detection.Furthermore,the RSSs during ferroptosis in He La cells have been evaluated using the present strategy,demonstrating the potential for ferroptosis examinations.This work has made an unconventional application of a fluorescent probe to enhance the detection of multiple RSSs by MS,providing significant molecular information for addressing the ferroptosis mechanism.展开更多
The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic s...The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.展开更多
A new coumarin derivative C2 was constructed to act as a highly effective turn-on fluorescent probe for Cu^(2+)ions.The introduction of Cu^(2+)could lead to the hydrolytic cleavage of the phenylhydrazone moiety in C2 ...A new coumarin derivative C2 was constructed to act as a highly effective turn-on fluorescent probe for Cu^(2+)ions.The introduction of Cu^(2+)could lead to the hydrolytic cleavage of the phenylhydrazone moiety in C2 and the transformation into strongly fluorescent aldehyde C1.Probe C2 could recognize Cu^(2+)through a marked fluorescence enhancement with the detection limit as low as 150 nmol/L.By virtue of this unique catalytic hydrolysis reaction,compound C2 displayed highly selective response toward Cu^(2+)over other common ions even in the presence of excessive competitive ions.Furthermore,there was a good linear relationship between the intensity change and the concentration of Cu^(2+)ions,which was beneficial for the exactly quantitative detection.Especially,the efficient detection of Cu^(2+)with C2 for the practical application was successfully performed in gas-generating agents detection.展开更多
Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Tra...Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Traditional technologies like ultrasonics and capacitor-antenna face challenges with limited detection areas,lower accuracy,and susceptibility to electromagnetic interference.Here,we introduce a novel viscosity-ultrasensitive fluorescent probe 40,4‴-(2,2-diphenyle-thene-1,1-diyl)bis-(3,5-dicarboxylate)(TPE-2B4C)based on AIEgens for moni-toring ice formation of anti-icing fluids in low-temperature environments.TPE-2B4C,consisting of four sodium carboxylate groups and multiple freely rotating benzene rings,demonstrates outstanding solubility in anti-icing fluids and exhibits no fluorescent background signal even at low temperatures(<−20°C).Upon freezing,TPE-2B4C relocates from the water phase to higher viscosity ethylene glycol,causing restriction of benzene rings and a significantly increased green fluorescence signal.TPE-2B4C can successfully determine whether the anti-icing fluids are icing from−5 to−20°C with a high contrast ratio.Due to its simple setup,fast operation,and broad applicability,our new method is anticipated to be employed for rapid,real-time,and large-scale icing detection.展开更多
In space probes,anomaly detection of sequence data collected by various sensors is essential to help detect potential faults promptly,improve the reliability of equipment operation,and ensure the smooth operation of t...In space probes,anomaly detection of sequence data collected by various sensors is essential to help detect potential faults promptly,improve the reliability of equipment operation,and ensure the smooth operation of the mission.However,sensors'signals often contain a superposition of various frequencies,changing fluctuations,and correlations between features.This complexity of data attributes makes building effective models challenging.This paper proposes a TimeEvolving Multi-Period Observational(TEMPO)anomaly detection method for space probes.First,fusing wavelet analysis and natural periods improves the ability to capture multi-period features in data.Then,the feature extraction framework proposed enhances the effectiveness of anomaly detection by comprehensively extracting the complex features of data through the multi-module synergy of temporal and channel.The results demonstrate that the proposed method enhances anomaly detection accuracy and its effectiveness is confirmed.Additionally,the ablation experiment results further validate the efficacy of each module.An evaluation of the algorithm's computational complexity confirms its suitability for real-time processing.展开更多
The effective detection depth of the needle-like optical probe is studied. The light transport model in highly scattering tissue is the diffusion equation and the boundary is Neuman. The sensitivity matrix is related ...The effective detection depth of the needle-like optical probe is studied. The light transport model in highly scattering tissue is the diffusion equation and the boundary is Neuman. The sensitivity matrix is related to the position of the light source and the detector. It can be used to evaluate the effective detection depth. The sensitivity matrix is defined as the multiplication of the source and detector hght distribution. Six different groups about ix parameters including the source diameter and detector fibers, the core-to-core distance between the source and detector fibers, the opotode depth, the absorption, and reduced scattering coefficient, are used as experimental models. The relationship between the six parameters and the effective detection depth is analyzed. Resuits can be used to study the spatial resolution and the depth of multi-fibers.展开更多
The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient monitoring.In this paper,an innovative approac...The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient monitoring.In this paper,an innovative approach is presented that leverages the power of machine learning to enhance the accuracy and efficiency of fluorescence-based detection for sequential quantitative analysis of aluminum(Al^(3+))and fluoride(F^(−))ions in aqueous solutions.The proposed method involves the synthesis of sulfur-functionalized carbon dots(C-dots)as fluorescence probes,with fluorescence enhancement upon interaction with Al^(3+)ions,achieving a detection limit of 4.2 nmol/L.Subsequently,in the presence of F^(−)ions,fluorescence is quenched,with a detection limit of 47.6 nmol/L.The fingerprints of fluorescence images are extracted using a cross-platform computer vision library in Python,followed by data preprocessing.Subsequently,the fingerprint data is subjected to cluster analysis using the K-means model from machine learning,and the average Silhouette Coefficient indicates excellent model performance.Finally,a regression analysis based on the principal component analysis method is employed to achieve more precise quantitative analysis of aluminum and fluoride ions.The results demonstrate that the developed model excels in terms of accuracy and sensitivity.This groundbreaking model not only showcases exceptional performance but also addresses the urgent need for effective environmental monitoring and risk assessment,making it a valuable tool for safeguarding our ecosystems and public health.展开更多
This paper proposes a lightweight traffic sign detection system based on you only look once(YOLO).Firstly,the classification to fusion(C2f)structure is integrated into the backbone network,employing deformable convolu...This paper proposes a lightweight traffic sign detection system based on you only look once(YOLO).Firstly,the classification to fusion(C2f)structure is integrated into the backbone network,employing deformable convolution and bi-directional feature pyramid network(BiFPN)_Concat to improve the adaptability of the network.Secondly,the simple attention module(SimAm)is embedded to prioritize key features and reduce the complexity of the model after the C2f layer at the end of the backbone network.Next,the focal efficient intersection over union(EloU)is introduced to adjust the weights of challenging samples.Finally,we accomplish the design and deployment for the mobile app.The results demonstrate improvements,with the F1 score of 0.8987,mean average precision(mAP)@0.5 of 98.8%,mAP@0.5:0.95 of 75.6%,and the detection speed of 50 frames per second(FPS).展开更多
Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for...Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for Ca^(2+)and Mn^(2+)is significant for water quality monitoring and human health.In this paper,blue fluorescent Ti3C2 MXene-based quantum dots(MQDs,λ_(em)=445 nm)are prepared using Ti_(3)C_(2)MXene as the precursor.Through the chelation effect of ethylene diamine tetraacetic acid(EDTA),a blue and red dual-emission fluorescent probe,MQDs-EDTA-Eu^(3+)-DPA,was constructed.Herein,dipicolinic acid(DPA)acts as an absorbing ligand and significantly enhances the red fluorescence of europium ions(Eu^(3+))at 616 nm through the“antenna effect”.The blue fluorescence of MQDs serves as an internal reference signal.High concentrations of Ca^(2+)can quench the red fluorescence of Eu^(3+)-DPA;Mn^(2+)can be excited to emit purple fluorescence at 380 nm after coordinating with DPA,red fluorescence of Eu^(3+)-DPA serves as the internal reference signal.Based on the above two fluorescence intensity changes,ratiometric fluorescence detection methods for Ca^(2+)and Mn^(2+)are established.The fluorescence intensity ratio(IF_(616)/IF_(445))exhibits a linear relationship with Ca^(2+)in the range of 35-120μmol/L,with a detection limit of 5.98μmol/L.The fluorescence intensity ratio(IF_(380)/IF_(616))shows good linearity with Mn^(2+)in the range of 0-14μmol/L,with a detection limit of 28.6 nmol/L.This method was successfully applied to the quantitative analysis of Ca^(2+)and Mn^(2+)in commercially available mineral water(Nongfu Spring,Ganten,and Evergrande),with recovery rates of 80.6%-117%and relative standard deviations(RSD)of 0.76%-4.6%.Additionally,by preparing MQD-based fluorescent test strips,visual detections of Ca^(2+)and Mn^(2+)are achieved.This work demonstrates the application potential of MQDs in the field of visual fluorescence sensing of ions in water quality.展开更多
Cysteine(Cys)plays a pivotal role in many physiological and pathological processes,including detoxification and protein synthesis.The abnormal levels of Cys are linked to many diseases.In this study,a novel red-emitti...Cysteine(Cys)plays a pivotal role in many physiological and pathological processes,including detoxification and protein synthesis.The abnormal levels of Cys are linked to many diseases.In this study,a novel red-emitting off-on fluorescent probe Cys-TCF was masterly constructed for discriminative detection of Cys.After a series of experimental assessment,Cys-TCF displayed higher selectivity and sensitivity for Cys over other biothilols with a low detection limit(0.04μmol/L).More notably,the probe was also successfully applied to image Cys in live cells and live zebrafishes with low cytotoxicity.展开更多
By modifying the salicylic-acid moiety with electron-withdrawing or –donating groups, three new terbium complexes（LⅠ·Tb, LⅡ·Tb, L·（Ⅲ）Tb） based on tripodal carboxylate ligands were synthesized. D...By modifying the salicylic-acid moiety with electron-withdrawing or –donating groups, three new terbium complexes（LⅠ·Tb, LⅡ·Tb, L·（Ⅲ）Tb） based on tripodal carboxylate ligands were synthesized. Due to different pull-push electronic effects of ligands, the fluorescence intensities of these terbium complexes significantly varied, that is： LⅡ·Tb 〉L（Ⅲ）·Tb〉 LⅠ·Tb. Meanwhile, the characteristic peaks at 492 nm（5D4→7F6） and 547 nm（5 D4→7F5） showed ＂Off–On–Off＂ fluorescence response to various p H conditions,which indicated that all of them can be used as the highly sensitive pH fluorescent probes. Notably, using LⅡ·Tb with the best fluorescence performance as a probe, some patients＇ urine samples can be easily monitored through the response triggered by pH value. Therefore, LⅡ·Tb has the potential to auxiliarily diagnose some diseases in clinical practice through p H detection of routine urine test.展开更多
Highly sensitive methods are important for monitoring the concentration of metal ions in industrial wastewater.Here,we developed a new probe for the determination of metal ions by fluorescence quenching.The probe cons...Highly sensitive methods are important for monitoring the concentration of metal ions in industrial wastewater.Here,we developed a new probe for the determination of metal ions by fluorescence quenching.The probe consists of hydroxylated graphene quantum dots(H-GQDs),prepared from GQDs by electrochemical method followed by surface hydroxylation.It is a non-reactive indicator with high sensitivity and detection limits of 0.01μM for Cu2+,0.005μM for Al3+,0.04μM for Fe3+,and 0.02μM for Cr3+.In addition,the low biotoxicity and excellent solubility of H-GQDs make them promising for application in wastewater metal ion detection.展开更多
In order to evaluate the performance of a molecular Hain line probe assay （Hain LPA） for rapid detection of rifampicin and isoniazid resistance of Mycobocterium tuberculosis in China, 1612 smear positive patients we...In order to evaluate the performance of a molecular Hain line probe assay （Hain LPA） for rapid detection of rifampicin and isoniazid resistance of Mycobocterium tuberculosis in China, 1612 smear positive patients were consecutively enrolled in this study. Smear positive sputum specimens were collected for Hain LPA and conventional drug susceptibility testing （DST）. The sensitivity and specificity of Hain LPA were analyzed by using conventional DST as golden reference. The sensitivity, specificity, positive predictive value {PPV） and negative predictive value （NPV） for rifampicin resistance detection were 88.33%, 97.66%, 81.54%, and 98.62%, respectively. The sensitivity, specificity, PPV and NPV for isoniazid resistance detection were 80.25%, 98.07%, 87.25%, and 96.78%, respectively. These findings suggested that Hain LPA can be an effective method worthy of broader use in China.展开更多
Two kinds of fluorescent nano-probes（pH-A and pH-B） with different diameters for the determination of H＋concentration, based on photo-induced electron transfer mechanism, were synthesized through click reaction. In...Two kinds of fluorescent nano-probes（pH-A and pH-B） with different diameters for the determination of H＋concentration, based on photo-induced electron transfer mechanism, were synthesized through click reaction. In which 1,8-naphthalimide was employed as the fluorophore and N,N-dimethylethylenediamine as the receptor. The effects of particle size and linker length on the photophysical properties of the probe were studied. The results revealed that the nano-probes were more sensitive toward pH with increasing particle size. The fluorescence intensity at 529 nm（I529） of the nano-probe p H-A of 120 nm exhibited good linear relationship with solution＇s pH in the range of 6–8. The probe p H-A displayed excellent selectivity and competition toward proton over other possible coexisted ions, and it could be applied to detect pH in realistic samples（river water, urine）.展开更多
A series of near-infrared(NIR)fluorescent substrates(NDRO-1∼8)derived from fluorophore NDRH with different volumes of ester bond as the recognition group were designed and synthesized for the detection of acetylcholi...A series of near-infrared(NIR)fluorescent substrates(NDRO-1∼8)derived from fluorophore NDRH with different volumes of ester bond as the recognition group were designed and synthesized for the detection of acetylcholinesterase(AChE),among which NDRO-1 with the smallest acetate group displayed the highest activity toward AChE.The detection limit of NDRO-1 for sensing AChE was 0.32μg/mL,and K_(m )was 6.40μmol/L,indicating ultra-sensitivity and good affinity of NDRO-1 toward AChE.NDRO-1 was used to detect the inhibitory of four kinds of pesticides including methamidophos,dichlorvos,and the detection limit was lower than 50μg/L,which was further used in pesticide residues detection.展开更多
Hypochlorous acid（HOCl） plays a vital role in many physiological and pathological processes as one of reactive oxygen species（ROS）. Developing highly sensitive and selective methods for HOCl detection is of signif...Hypochlorous acid（HOCl） plays a vital role in many physiological and pathological processes as one of reactive oxygen species（ROS）. Developing highly sensitive and selective methods for HOCl detection is of significant interest. In this work, we developed a benzothiazole based probe 1 for ratiometric fluorescence detection of hypochlorite in living cells. The probe can detect HOCl with high selectivity, fast response（within 30 s） as well as low detection limit（0.18 mmol/L）. Fluorescence co-localization studies demonstrated that probe 1 was a mitochondria-targeted fluorescent probe. Furthermore, confocal fluorescence images of He La cell indicated that probe 1 could be used for monitoring intracellular HOCl in living cells. Finally, test strips experiment suggests that the probe 1 can detect the hypochlorous acid in tap water accompanied by remarkable color change.展开更多
We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting n...We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting nanoparticles (NPs) were characterized in terms of UV, fluorescence and FT-IR spectroscopy and TEM. The results show that the new NPs display more intense fluorescence intensity and are more stable than its precursors of the type SiO2/CdTe. Under the optimum, the novel NPs exhibit a higher selectivity and ultrasensitive fluorescence probes for the determination of gly-phosate over other pesticides, the fluorescence intensity increase with the concentration of glyphosate in the range from 1.0 to 25.0 nmol/L and the detection limit is low to 0.0725 nmol/L. A mechanism is suggested to explain the inclusion process by a Langmuir binding isotherm.展开更多
In this study,a natural cotton thread immunoassay device combined with gold nanorod（GNR） reporter probe is developed for the rapid,sensitive and quantitative electrochemical determination of human ferritin,a lung ca...In this study,a natural cotton thread immunoassay device combined with gold nanorod（GNR） reporter probe is developed for the rapid,sensitive and quantitative electrochemical determination of human ferritin,a lung cancer related biomarker.Human ferritin as an analyte and a pair of monoclonal antibodies are used to demonstrate the proof-of-concept on the cotton thread immunoassay device.An enhancement of the sensitivity is achieved by using gold nanorod as an electroactive report probe compared with a traditional gold nanoparticle（GNP） report probe.The device was capable of measuring 1.58 ng/mL ferritin in 30 min by anodic stripping voltammetry（ASV） testing,which meet the requirement for clinical diagnosis.展开更多
A new fluorescence probe 2,2’-(6-(4-(diethylamino) phenyl)-1,3,5-triazine-2,4-diyl)bis(1 H-pyrazole-1,3-diyl) diacetate(EATPA) based on 1, 3, 5-triazine was designed and synthesized. It exhibited distinct fluorescenc...A new fluorescence probe 2,2’-(6-(4-(diethylamino) phenyl)-1,3,5-triazine-2,4-diyl)bis(1 H-pyrazole-1,3-diyl) diacetate(EATPA) based on 1, 3, 5-triazine was designed and synthesized. It exhibited distinct fluorescence quenching in the presence of silver ions that can be used for highly sensitive and selective detection of Ag^+. Fluorescence titration and Job’s plot analysis revealed the formation of [Ag(EATPA)2]^+ entity with high binding constant(1.43×10^4 L/mol) and low detection limit(0.882 μmol/L). Furthermore, live-cell imaging experiments demonstrated that EATPA is potentially applicable for the tracking of Ag^+ in living cells.展开更多
基金supported by the National Key Research and Development Program of China (No.2024YFA1509600)National Natural Science Foundation of China (Nos.22474010 and 22274012)the Fundamental Research Funds for the Central Universities (No.2233300007)。
文摘Ferroptosis has exhibited great potential in therapies and intracellular reducing agents of sulfur species(RSSs) in the thiol-dependent redox systems are crucial in ferroptosis.This makes the simultaneous detection of multiple RSSs significant for evaluating ferroptosis therapy.However,the traditional techniques,including fluorescent(FL) imaging and electrospray ionization-based mass spectrometry(MS) detection,cannot achieve the discrimination of different RSSs.Herein,simultaneous MS detection of multiple RSSs,including cysteine(Cys),homocysteine(Hcy),glutathione(GSH) and hydrogen sulfide(H_(2)S),was obtained upon enhancing ionization efficiency by a fluorescent probe(NBD-O-1).Based on the interaction between NBD-O-1 and RSSs,the complex of RSSs with a fragment of NBD-O-1 can be generated,which can be easily ionized for MS detection in the negative mode.Therefore,the intracellular RSSs can be well detected upon the incubation of He La cells with the probe of NBD-O-1,exhibiting the total RSS levels by the FL imaging and further providing expression of each RSS by enhanced MS detection.Furthermore,the RSSs during ferroptosis in He La cells have been evaluated using the present strategy,demonstrating the potential for ferroptosis examinations.This work has made an unconventional application of a fluorescent probe to enhance the detection of multiple RSSs by MS,providing significant molecular information for addressing the ferroptosis mechanism.
文摘The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.
文摘A new coumarin derivative C2 was constructed to act as a highly effective turn-on fluorescent probe for Cu^(2+)ions.The introduction of Cu^(2+)could lead to the hydrolytic cleavage of the phenylhydrazone moiety in C2 and the transformation into strongly fluorescent aldehyde C1.Probe C2 could recognize Cu^(2+)through a marked fluorescence enhancement with the detection limit as low as 150 nmol/L.By virtue of this unique catalytic hydrolysis reaction,compound C2 displayed highly selective response toward Cu^(2+)over other common ions even in the presence of excessive competitive ions.Furthermore,there was a good linear relationship between the intensity change and the concentration of Cu^(2+)ions,which was beneficial for the exactly quantitative detection.Especially,the efficient detection of Cu^(2+)with C2 for the practical application was successfully performed in gas-generating agents detection.
基金support from the National Natural Science Foundation of China(9235630033,22105069)Shanghai Pujiang Program(20PJ1402900)+2 种基金Shanghai Natural Science Foundation(21ZR1418400)Innovation Program of Shanghai Municipal Education Commission(2023FGS01)Natural Science Foundation of Jiangsu Province(BK20231225).
文摘Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Traditional technologies like ultrasonics and capacitor-antenna face challenges with limited detection areas,lower accuracy,and susceptibility to electromagnetic interference.Here,we introduce a novel viscosity-ultrasensitive fluorescent probe 40,4‴-(2,2-diphenyle-thene-1,1-diyl)bis-(3,5-dicarboxylate)(TPE-2B4C)based on AIEgens for moni-toring ice formation of anti-icing fluids in low-temperature environments.TPE-2B4C,consisting of four sodium carboxylate groups and multiple freely rotating benzene rings,demonstrates outstanding solubility in anti-icing fluids and exhibits no fluorescent background signal even at low temperatures(<−20°C).Upon freezing,TPE-2B4C relocates from the water phase to higher viscosity ethylene glycol,causing restriction of benzene rings and a significantly increased green fluorescence signal.TPE-2B4C can successfully determine whether the anti-icing fluids are icing from−5 to−20°C with a high contrast ratio.Due to its simple setup,fast operation,and broad applicability,our new method is anticipated to be employed for rapid,real-time,and large-scale icing detection.
基金supported by the National Natural Science Foundation of China(Nos.92467108,62141604,62032016,92467206)Beijing Nova Program,China No.(20220484106,20230484451)。
文摘In space probes,anomaly detection of sequence data collected by various sensors is essential to help detect potential faults promptly,improve the reliability of equipment operation,and ensure the smooth operation of the mission.However,sensors'signals often contain a superposition of various frequencies,changing fluctuations,and correlations between features.This complexity of data attributes makes building effective models challenging.This paper proposes a TimeEvolving Multi-Period Observational(TEMPO)anomaly detection method for space probes.First,fusing wavelet analysis and natural periods improves the ability to capture multi-period features in data.Then,the feature extraction framework proposed enhances the effectiveness of anomaly detection by comprehensively extracting the complex features of data through the multi-module synergy of temporal and channel.The results demonstrate that the proposed method enhances anomaly detection accuracy and its effectiveness is confirmed.Additionally,the ablation experiment results further validate the efficacy of each module.An evaluation of the algorithm's computational complexity confirms its suitability for real-time processing.
基金Supported by the Natural Science Foundation of Jiangsu Province (BK2009371)the National High Technology Research and Development Program of China ("863" Program) (2008AA02Z438)~~
文摘The effective detection depth of the needle-like optical probe is studied. The light transport model in highly scattering tissue is the diffusion equation and the boundary is Neuman. The sensitivity matrix is related to the position of the light source and the detector. It can be used to evaluate the effective detection depth. The sensitivity matrix is defined as the multiplication of the source and detector hght distribution. Six different groups about ix parameters including the source diameter and detector fibers, the core-to-core distance between the source and detector fibers, the opotode depth, the absorption, and reduced scattering coefficient, are used as experimental models. The relationship between the six parameters and the effective detection depth is analyzed. Resuits can be used to study the spatial resolution and the depth of multi-fibers.
基金supported by the National Natural Science Foundation of China(No.U21A20290)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515011656)+2 种基金the Projects of Talents Recruitment of GDUPT(No.2023rcyj1003)the 2022“Sail Plan”Project of Maoming Green Chemical Industry Research Institute(No.MMGCIRI2022YFJH-Y-024)Maoming Science and Technology Project(No.2023382).
文摘The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient monitoring.In this paper,an innovative approach is presented that leverages the power of machine learning to enhance the accuracy and efficiency of fluorescence-based detection for sequential quantitative analysis of aluminum(Al^(3+))and fluoride(F^(−))ions in aqueous solutions.The proposed method involves the synthesis of sulfur-functionalized carbon dots(C-dots)as fluorescence probes,with fluorescence enhancement upon interaction with Al^(3+)ions,achieving a detection limit of 4.2 nmol/L.Subsequently,in the presence of F^(−)ions,fluorescence is quenched,with a detection limit of 47.6 nmol/L.The fingerprints of fluorescence images are extracted using a cross-platform computer vision library in Python,followed by data preprocessing.Subsequently,the fingerprint data is subjected to cluster analysis using the K-means model from machine learning,and the average Silhouette Coefficient indicates excellent model performance.Finally,a regression analysis based on the principal component analysis method is employed to achieve more precise quantitative analysis of aluminum and fluoride ions.The results demonstrate that the developed model excels in terms of accuracy and sensitivity.This groundbreaking model not only showcases exceptional performance but also addresses the urgent need for effective environmental monitoring and risk assessment,making it a valuable tool for safeguarding our ecosystems and public health.
基金supported by the Shanxi Agricultural University Science and Technology Innovation Enhancement Project。
文摘This paper proposes a lightweight traffic sign detection system based on you only look once(YOLO).Firstly,the classification to fusion(C2f)structure is integrated into the backbone network,employing deformable convolution and bi-directional feature pyramid network(BiFPN)_Concat to improve the adaptability of the network.Secondly,the simple attention module(SimAm)is embedded to prioritize key features and reduce the complexity of the model after the C2f layer at the end of the backbone network.Next,the focal efficient intersection over union(EloU)is introduced to adjust the weights of challenging samples.Finally,we accomplish the design and deployment for the mobile app.The results demonstrate improvements,with the F1 score of 0.8987,mean average precision(mAP)@0.5 of 98.8%,mAP@0.5:0.95 of 75.6%,and the detection speed of 50 frames per second(FPS).
基金The Tertiary Education Scientific Research Project of the Guangzhou Municipal Education Bureau(2024312227)Innovative and Entrepreneurial Projects of Guangzhou University Students(202411078014)+2 种基金Guangzhou University Open Sharing Fund for Instruments and Equipment(2025)National Major Scientific Research Instrument Development Project(22227804)Sub-subject of the National Key Research Project(2023YFB3210100)。
文摘Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for Ca^(2+)and Mn^(2+)is significant for water quality monitoring and human health.In this paper,blue fluorescent Ti3C2 MXene-based quantum dots(MQDs,λ_(em)=445 nm)are prepared using Ti_(3)C_(2)MXene as the precursor.Through the chelation effect of ethylene diamine tetraacetic acid(EDTA),a blue and red dual-emission fluorescent probe,MQDs-EDTA-Eu^(3+)-DPA,was constructed.Herein,dipicolinic acid(DPA)acts as an absorbing ligand and significantly enhances the red fluorescence of europium ions(Eu^(3+))at 616 nm through the“antenna effect”.The blue fluorescence of MQDs serves as an internal reference signal.High concentrations of Ca^(2+)can quench the red fluorescence of Eu^(3+)-DPA;Mn^(2+)can be excited to emit purple fluorescence at 380 nm after coordinating with DPA,red fluorescence of Eu^(3+)-DPA serves as the internal reference signal.Based on the above two fluorescence intensity changes,ratiometric fluorescence detection methods for Ca^(2+)and Mn^(2+)are established.The fluorescence intensity ratio(IF_(616)/IF_(445))exhibits a linear relationship with Ca^(2+)in the range of 35-120μmol/L,with a detection limit of 5.98μmol/L.The fluorescence intensity ratio(IF_(380)/IF_(616))shows good linearity with Mn^(2+)in the range of 0-14μmol/L,with a detection limit of 28.6 nmol/L.This method was successfully applied to the quantitative analysis of Ca^(2+)and Mn^(2+)in commercially available mineral water(Nongfu Spring,Ganten,and Evergrande),with recovery rates of 80.6%-117%and relative standard deviations(RSD)of 0.76%-4.6%.Additionally,by preparing MQD-based fluorescent test strips,visual detections of Ca^(2+)and Mn^(2+)are achieved.This work demonstrates the application potential of MQDs in the field of visual fluorescence sensing of ions in water quality.
基金financial supports from the National Natural Science Foundation of China (Nos.21708017,21572093,21778028)Lanzhou University (the Fundamental Research Funds for the Central Universities,No.lzujbky-2018-64)Natural Science Foundation of Gansu Province (No.17JR5RA193)
文摘Cysteine(Cys)plays a pivotal role in many physiological and pathological processes,including detoxification and protein synthesis.The abnormal levels of Cys are linked to many diseases.In this study,a novel red-emitting off-on fluorescent probe Cys-TCF was masterly constructed for discriminative detection of Cys.After a series of experimental assessment,Cys-TCF displayed higher selectivity and sensitivity for Cys over other biothilols with a low detection limit(0.04μmol/L).More notably,the probe was also successfully applied to image Cys in live cells and live zebrafishes with low cytotoxicity.
基金supported by the National Natural Science Foundation of China (Nos. 21572091 and 21472075)the Fundamental Research Funds for the Central Universities (No. lzujbky-2016-51) by Ministry of Education of China
文摘By modifying the salicylic-acid moiety with electron-withdrawing or –donating groups, three new terbium complexes（LⅠ·Tb, LⅡ·Tb, L·（Ⅲ）Tb） based on tripodal carboxylate ligands were synthesized. Due to different pull-push electronic effects of ligands, the fluorescence intensities of these terbium complexes significantly varied, that is： LⅡ·Tb 〉L（Ⅲ）·Tb〉 LⅠ·Tb. Meanwhile, the characteristic peaks at 492 nm（5D4→7F6） and 547 nm（5 D4→7F5） showed ＂Off–On–Off＂ fluorescence response to various p H conditions,which indicated that all of them can be used as the highly sensitive pH fluorescent probes. Notably, using LⅡ·Tb with the best fluorescence performance as a probe, some patients＇ urine samples can be easily monitored through the response triggered by pH value. Therefore, LⅡ·Tb has the potential to auxiliarily diagnose some diseases in clinical practice through p H detection of routine urine test.
基金financially supported by the National Natural Science Foundation of China (No. 21674011)Beijing Municipal Natural Science Foundation (No. 2172040)
文摘Highly sensitive methods are important for monitoring the concentration of metal ions in industrial wastewater.Here,we developed a new probe for the determination of metal ions by fluorescence quenching.The probe consists of hydroxylated graphene quantum dots(H-GQDs),prepared from GQDs by electrochemical method followed by surface hydroxylation.It is a non-reactive indicator with high sensitivity and detection limits of 0.01μM for Cu2+,0.005μM for Al3+,0.04μM for Fe3+,and 0.02μM for Cr3+.In addition,the low biotoxicity and excellent solubility of H-GQDs make them promising for application in wastewater metal ion detection.
基金supported by Bill&Melinda Gates Foundation Tuberculosis Prevention and Control Project(2009-04-01)
文摘In order to evaluate the performance of a molecular Hain line probe assay （Hain LPA） for rapid detection of rifampicin and isoniazid resistance of Mycobocterium tuberculosis in China, 1612 smear positive patients were consecutively enrolled in this study. Smear positive sputum specimens were collected for Hain LPA and conventional drug susceptibility testing （DST）. The sensitivity and specificity of Hain LPA were analyzed by using conventional DST as golden reference. The sensitivity, specificity, positive predictive value {PPV） and negative predictive value （NPV） for rifampicin resistance detection were 88.33%, 97.66%, 81.54%, and 98.62%, respectively. The sensitivity, specificity, PPV and NPV for isoniazid resistance detection were 80.25%, 98.07%, 87.25%, and 96.78%, respectively. These findings suggested that Hain LPA can be an effective method worthy of broader use in China.
基金financial support from the National Natural Science Foundation of China (No. 21576085)
文摘Two kinds of fluorescent nano-probes（pH-A and pH-B） with different diameters for the determination of H＋concentration, based on photo-induced electron transfer mechanism, were synthesized through click reaction. In which 1,8-naphthalimide was employed as the fluorophore and N,N-dimethylethylenediamine as the receptor. The effects of particle size and linker length on the photophysical properties of the probe were studied. The results revealed that the nano-probes were more sensitive toward pH with increasing particle size. The fluorescence intensity at 529 nm（I529） of the nano-probe p H-A of 120 nm exhibited good linear relationship with solution＇s pH in the range of 6–8. The probe p H-A displayed excellent selectivity and competition toward proton over other possible coexisted ions, and it could be applied to detect pH in realistic samples（river water, urine）.
基金supported financially by National Key R&D Program of China (No. 2018YFC1603001)
文摘A series of near-infrared(NIR)fluorescent substrates(NDRO-1∼8)derived from fluorophore NDRH with different volumes of ester bond as the recognition group were designed and synthesized for the detection of acetylcholinesterase(AChE),among which NDRO-1 with the smallest acetate group displayed the highest activity toward AChE.The detection limit of NDRO-1 for sensing AChE was 0.32μg/mL,and K_(m )was 6.40μmol/L,indicating ultra-sensitivity and good affinity of NDRO-1 toward AChE.NDRO-1 was used to detect the inhibitory of four kinds of pesticides including methamidophos,dichlorvos,and the detection limit was lower than 50μg/L,which was further used in pesticide residues detection.
基金supported by the National Natural Science Foundation of China(Nos.21376117,21406109 and 31401588)the Jiangsu Natural Science Funds for Distinguished Young Scholars(No.BK20140043)+1 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.14KJA150005)the Qing Lan Project and the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Hypochlorous acid（HOCl） plays a vital role in many physiological and pathological processes as one of reactive oxygen species（ROS）. Developing highly sensitive and selective methods for HOCl detection is of significant interest. In this work, we developed a benzothiazole based probe 1 for ratiometric fluorescence detection of hypochlorite in living cells. The probe can detect HOCl with high selectivity, fast response（within 30 s） as well as low detection limit（0.18 mmol/L）. Fluorescence co-localization studies demonstrated that probe 1 was a mitochondria-targeted fluorescent probe. Furthermore, confocal fluorescence images of He La cell indicated that probe 1 could be used for monitoring intracellular HOCl in living cells. Finally, test strips experiment suggests that the probe 1 can detect the hypochlorous acid in tap water accompanied by remarkable color change.
文摘We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting nanoparticles (NPs) were characterized in terms of UV, fluorescence and FT-IR spectroscopy and TEM. The results show that the new NPs display more intense fluorescence intensity and are more stable than its precursors of the type SiO2/CdTe. Under the optimum, the novel NPs exhibit a higher selectivity and ultrasensitive fluorescence probes for the determination of gly-phosate over other pesticides, the fluorescence intensity increase with the concentration of glyphosate in the range from 1.0 to 25.0 nmol/L and the detection limit is low to 0.0725 nmol/L. A mechanism is suggested to explain the inclusion process by a Langmuir binding isotherm.
基金financially supported by the National Natural Science Foundation of China (No. 21205094)NFFTBS (Nos. J1103311,J1210057)the New Faculty Startup Funds of Northwest University in Shaanxi Province (No. PR12011)
文摘In this study,a natural cotton thread immunoassay device combined with gold nanorod（GNR） reporter probe is developed for the rapid,sensitive and quantitative electrochemical determination of human ferritin,a lung cancer related biomarker.Human ferritin as an analyte and a pair of monoclonal antibodies are used to demonstrate the proof-of-concept on the cotton thread immunoassay device.An enhancement of the sensitivity is achieved by using gold nanorod as an electroactive report probe compared with a traditional gold nanoparticle（GNP） report probe.The device was capable of measuring 1.58 ng/mL ferritin in 30 min by anodic stripping voltammetry（ASV） testing,which meet the requirement for clinical diagnosis.
基金supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (No. 2015BAD16B01)TianjinKey Technology Research and Development Support Program (No. 13ZCDNC01900)
基金Supported by the National Natural Science Foundation of China(21401144)the Natural Science Foundation of Hubei Province(2013CFB236)the Independent Research Discipline Cross-funding of Wuhan University(2042017kf0215)
文摘A new fluorescence probe 2,2’-(6-(4-(diethylamino) phenyl)-1,3,5-triazine-2,4-diyl)bis(1 H-pyrazole-1,3-diyl) diacetate(EATPA) based on 1, 3, 5-triazine was designed and synthesized. It exhibited distinct fluorescence quenching in the presence of silver ions that can be used for highly sensitive and selective detection of Ag^+. Fluorescence titration and Job’s plot analysis revealed the formation of [Ag(EATPA)2]^+ entity with high binding constant(1.43×10^4 L/mol) and low detection limit(0.882 μmol/L). Furthermore, live-cell imaging experiments demonstrated that EATPA is potentially applicable for the tracking of Ag^+ in living cells.
