It is easy for teenagers to view pornographic pictures on social networks. Many researchers have studied the detection of real pornographic pictures, but there are few studies on those that are artificial. In this wor...It is easy for teenagers to view pornographic pictures on social networks. Many researchers have studied the detection of real pornographic pictures, but there are few studies on those that are artificial. In this work, we studied how to detect artificial pornographic pictures, especially when they are on social networks. The whole detection process can be divided into two stages： feature selection and picture detection. In the feature selection stage, seven types of features that favour picture detection were selected. In the picture detection stage, three steps were included. 1） In order to alleviate the imbalance in the number of artificial pornographic pictures and normal ones, the training dataset of artificial pornographic pictures was expanded. Therefore, the features which were extracted from the training dataset can also be expanded too. 2） In order to reduce the time of feature extraction, a fast method which extracted features based on the proportionally scaled picture rather than the original one was proposed. 3） Three tree models were compared and a gradient boost decision tree （GBDT） was selected for the final picture detection. Three sets of experimental results show that the proposed method can achieve better recognition precision and drastically reduce the time cost of the method.展开更多
BACKGROUND Multiple endocrine neoplasias(MENs)are a group of hereditary diseases invol-ving multiple endocrine glands,and their prevalence is low.MEN type 1(MEN1)has diverse clinical manifestations,mainly involving th...BACKGROUND Multiple endocrine neoplasias(MENs)are a group of hereditary diseases invol-ving multiple endocrine glands,and their prevalence is low.MEN type 1(MEN1)has diverse clinical manifestations,mainly involving the parathyroid glands,gastrointestinal tract,pancreas and pituitary gland,making it easy to miss the clinical diagnosis.CASE SUMMARY We present the case of a patient in whom MEN1 was detected early.A middle-aged male with recurrent abdominal pain and diarrhea was admitted to the hos-pital.Blood tests at admission revealed hypercalcemia and hypophosphatemia,and emission computed tomography of the parathyroid glands revealed a hy-perfunctioning parathyroid lesion.Gastroscopy findings suggested a duodenal bulge and ulceration.Ultrasound endoscopy revealed a hypoechoic lesion in the duodenal bulb.Further blood tests revealed elevated levels of serum gastrin.Surgery was performed,and pathological analysis of the surgical specimens revealed a parathyroid adenoma after parathyroidectomy and a neuroendocrine tumor after duodenal bulbectomy.The time from onset to the definitive diagnosis of MEN1 was only approximately 1 year.CONCLUSION For patients who present with gastrointestinal symptoms accompanied by hyper-calcemia and hypophosphatemia,clinicians need to be alert to the possibility of MEN1.展开更多
With the complexity of integrated circuits is continually increasing, a local defect in circuits may cause multiple faults. The behavior of a digital circuit with a multiple fault may significantly differ from that of...With the complexity of integrated circuits is continually increasing, a local defect in circuits may cause multiple faults. The behavior of a digital circuit with a multiple fault may significantly differ from that of a single fault. A new method for the detection of multiple faults in digital circuits is presented in this paper, the method is based on binary decision diagram （BDD）. First of all, the BDDs for the normal circuit and faulty circuit are built respectively. Secondly, a test BDD is obtained by the XOR operation of the BDDs corresponds to normal circuit and faulty circuit. In the test BDD, each input assignment that leads to the leaf node labeled 1 is a test vector of multiple faults. Therefore, the test set of multiple faults is generated by searching for the type of input assignments in the test BDD. Experimental results on some digital circuits show the feasibility of the approach presented in this paper.展开更多
The single fault and multiple fault detections for multiple-valued logic circuits are studied in this paper. Firstly, it is shown that the cardinality of optimal single fault test set for fanout-free m-valued circuits...The single fault and multiple fault detections for multiple-valued logic circuits are studied in this paper. Firstly, it is shown that the cardinality of optimal single fault test set for fanout-free m-valued circuits with n primary inputs is not more than n + 1, for linear tree circuits is two, and for multiplication modulo circuits is two if n is an odd number or if n is an even number and m ＞ 3, where the optimal test set of a circuit has minimal number of test vectors. Secondly,it is indicated that the cardinality of optimal multiple fault test set for linear tree circuits with n primary inputs is 1 + [n/(m - 1)], for multiplication modulo circuits is n+ 1, for fanout-free circuits that consist of 2-input linear tree circuits and 2-input multiplication modulo circuits is not greater than n+ 1, where [x] denotes the smallest integer greater than or equal to x. Finally,the single fault location approaches of linear tree circuits and multiplication modulo circuits are presented, and all faults in the two types of circuits can be located by using a test set with n + 1 vectors.展开更多
Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three t...Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.展开更多
The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the "false positives" results caused by a single biomolecule detections...The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the "false positives" results caused by a single biomolecule detections easily leads to erroneous clinical diagnosis and treatment. Thus, it is important for the homogenous quantification of multiple biomolecules in not only basic research but also practical application. As a consequent, a large number of literatures have been exploited to monitor multiple biomolecules in homogenous solution, enabling facilitating the development of the disease diagnosis, treatment as well as drug discovery. One-dimensional nanomaterials and two-dimensional nanomaterials have special physical and chemical properties, such as good electrochemical properties, stable structure, large specific surface area, and biocompatibility, which are widely used in electrochemical and fluorescent detection of biomolecules. This tutorial review highlights the recent development for the detection of multiple biomolecules by using nanomaterials including one-dimensional materials(1DMs) as well as twodimensional materials(2DMs).展开更多
A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave...A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave radar. This method defines a whole-peak-outlier elimination （WPOE） criterion, which is based on in-peak-samples correlation of each target echo spectra, to trim off the target signals and abnormal disturbances with great amplitude from the complex spectra. Therefore, cleaned background noise samples are obtained to improve the accuracy and reliability of noise level estimation. When the background noise is nonhomogeneous, the detection samples are limited and often occupied heavily with outliers. In this case, the problem that the detection threshold is overvalued can be solved. In applications on experimental data, it is verified that this method can reduce the miss alarm rate of signal detection effectively in multiple target situations as well as make the adaptability of the detector better.展开更多
[ Objective] To develop a rapid, sensitive, specific and accurate diagnostic method for subclinical mastitis in dairy cow. [ Method] A total of 70 samples of suspected clinical mastitis cows were detected in gene leve...[ Objective] To develop a rapid, sensitive, specific and accurate diagnostic method for subclinical mastitis in dairy cow. [ Method] A total of 70 samples of suspected clinical mastitis cows were detected in gene level by multiple PCR. [Result] The 58 samples were positive with the developed multiple PCR method and the positive rate was 82.5% （58/70）. The 53 samples were positive with the traditional biochemical method and the positive rate was 75.5% （53/70）. As a result, the coincidence rate of both methods was 92%. [ Conclusion] The multiple PCR method is rapid and specific for the detection of pathogenic subclinical mastitis in dairy cow.展开更多
Detection of point mutations in driver genes is of great significance for the early diagnosis,treatment,and prognostic evaluation of cancer.However,current detection methods do not offer versatility,specificity,and ra...Detection of point mutations in driver genes is of great significance for the early diagnosis,treatment,and prognostic evaluation of cancer.However,current detection methods do not offer versatility,specificity,and rapid performance simultaneously.Thus,multiple mutation detection processes are necessary,which results in long processing times and high costs.In this study,we developed a thermodynamics-guided two-way interlocking DNA cascade system for universal multiplexed mutation detection(TTI-CS).This strategy is based on the DNA probe,which changes the thermodynamic balance of the DNA cascade by the designed bubble structure,thereby achieving a good distinction between mutant and wild-type DNA.The designed method greatly shortens the detection time through two-way intrusion.In addition,this method only changes two inexpensive trigger and bridge sequences,which replace the specific and expensive nucleic acid probes used in analyses based on traditional DNA probe methods,thereby enabling multiple detections.We performed the detection of synthetic single-stranded DNA for the five mutation points and successfully detected in endometrial cancer specimens.The detection limit of this method is0.1%,which better meets the needs of clinical low-abundance multiple mutation detection.Overall,TTI-CS is currently one of the best methods for detecting multiple mutation detections.展开更多
Either amplitude based methods or phase based methods are usually used in multibeam bathymetry system and chosen in practical measurement by ad hoc criteria. The errors of the detection are often caused by choosing wr...Either amplitude based methods or phase based methods are usually used in multibeam bathymetry system and chosen in practical measurement by ad hoc criteria. The errors of the detection are often caused by choosing wrong detection method. In this paper a modified multiple subarrays amplitude-phase united detection method is proposed , which uses both the amplitude and phase of echo from bottom.This new method not only realizes the super-wide swath coverage, but also improves the detection performance by using the phase differences among subarrays in place of phases of subarrays to estimate the phase slope image. Experimental results are also analyzed and discussed to demonstrate the effectivity of the proposed approach.展开更多
Compared to 3D object detection using a single camera,multiple cameras can overcome some limitations on field-of-view,occlusion,and low detection confidence.This study employs multiple surveillance cameras and develop...Compared to 3D object detection using a single camera,multiple cameras can overcome some limitations on field-of-view,occlusion,and low detection confidence.This study employs multiple surveillance cameras and develops a cooperative 3D object detection and tracking framework by incorporating temporal and spatial information.The framework consists of a 3D vehicle detection model,cooperatively spatial-temporal relation scheme,and heuristic camera constellation method.Specifically,the proposed cross-camera association scheme combines the geometric relationship between multiple cameras and objects in corresponding detections.The spatial-temporal method is designed to associate vehicles between different points of view at a single timestamp and fulfill vehicle tracking in the time aspect.The proposed framework is evaluated based on a synthetic cooperative dataset and shows high reliability,where the cooperative perception can recall more than 66%of the trajectory instead of 11%for single-point sensing.This could contribute to full-range surveillance for intelligent transportation systems.展开更多
Synaptic dysfunction occurs early in Alzheimer＇s disease （AD） and is acknowledged as a primary pathologic target for treatment. Synaptic degeneration is the pathological feature most strongly correlated with loss o...Synaptic dysfunction occurs early in Alzheimer＇s disease （AD） and is acknowledged as a primary pathologic target for treatment. Synaptic degeneration is the pathological feature most strongly correlated with loss of cognitive function ante mortern （Terry et al., 1991）. Synapses are heavily damaged in hippocampal and neocortical regions of AD brain, whereas motor and occipital cortices are relatively spared （Honer et al., 1992）. Despite extensive work, the molecular mechanisms underlying synaptic degeneration are largely unknown.展开更多
The problem of fault detection for linear discrete timevarying systems with multiplicative noise is dealt with.By using an observer-based robust fault detection filter（FDF） as a residual generator,the design of the ...The problem of fault detection for linear discrete timevarying systems with multiplicative noise is dealt with.By using an observer-based robust fault detection filter（FDF） as a residual generator,the design of the FDF is formulated in the framework of H ∞ filtering for a class of stochastic time-varying systems.A sufficient condition for the existence of the FDF is derived in terms of a Riccati equation.The determination of the parameter matrices of the filter is converted into a quadratic optimization problem,and an analytical solution of the parameter matrices is obtained by solving the Riccati equation.Numerical examples are given to illustrate the effectiveness of the proposed method.展开更多
A number of statistical tests are proposed for the purpose of change-point detection in a general nonparametric regression model under mild conditions. New proofs are given to prove the weak convergence of the underly...A number of statistical tests are proposed for the purpose of change-point detection in a general nonparametric regression model under mild conditions. New proofs are given to prove the weak convergence of the underlying processes which assume remove the stringent condition of bounded total variation of the regression function and need only second moments. Since many quantities, such as the regression function, the distribution of the covariates and the distribution of the errors, are unspecified, the results are not distribution-free. A weighted bootstrap approach is proposed to approximate the limiting distributions. Results of a simulation study for this paper show good performance for moderate samples sizes.展开更多
A switching variability index （SVl） constant false alarm rate （CFAR） detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homo...A switching variability index （SVl） constant false alarm rate （CFAR） detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homogeneity in CFAR reference windows is indicated by a VI-CFAR detector, a switching- CFAR detector is introduced to optimize the performance of the VI-CFAR detector in homogeneous, multiple targets and clutter edge backgrounds. The structure and parameters selection method of the SVI-CFAR detector is presented. Comparisons with classic CFAR detectors and recently proposed detectors are also given. Theoretical analysis and simulation results show that SVICFAR detector maintains the good performance of the VI-CFAR detector in homogeneous and clutter edge backgrounds, while greatly improving the capacity of anti-multi targets.展开更多
As the use of deepfake facial videos proliferate,the associated threats to social security and integrity cannot be overstated.Effective methods for detecting forged facial videos are thus urgently needed.While many de...As the use of deepfake facial videos proliferate,the associated threats to social security and integrity cannot be overstated.Effective methods for detecting forged facial videos are thus urgently needed.While many deep learning-based facial forgery detection approaches show promise,they often fail to delve deeply into the complex relationships between image features and forgery indicators,limiting their effectiveness to specific forgery techniques.To address this challenge,we propose a dual-branch collaborative deepfake detection network.The network processes video frame images as input,where a specialized noise extraction module initially extracts the noise feature maps.Subsequently,the original facial images and corresponding noise maps are directed into two parallel feature extraction branches to concurrently learn texture and noise forgery clues.An attention mechanism is employed between the two branches to facilitate mutual guidance and enhancement of texture and noise features across four different scales.This dual-modal feature integration enhances sensitivity to forgery artifacts and boosts generalization ability across various forgery techniques.Features from both branches are then effectively combined and processed through a multi-layer perception layer to distinguish between real and forged video.Experimental results on benchmark deepfake detection datasets demonstrate that our approach outperforms existing state-of-the-art methods in terms of detection performance,accuracy,and generalization ability.展开更多
Large-grain REBa_(2)Cu_(3)O_(7-δ)(REBCO,RE=rare earth)bulk superconductors offer promising magnetic field trapping capabilities due to their high critical current density,making them ideal for many important applicat...Large-grain REBa_(2)Cu_(3)O_(7-δ)(REBCO,RE=rare earth)bulk superconductors offer promising magnetic field trapping capabilities due to their high critical current density,making them ideal for many important applications such as trapped field magnets.However,for such large-grain superconductor bulks,there are lots of voids and cracks forming during the process of melting preparation,and some of them can be up to hundreds of microns or even millimeters in size.Consequently,these larger size voids/cracks pose a great threat to the strength of the bulks due to the inherent brittleness of superconductor REBCO materials.In order to ensure the operational safety of related superconducting devices with bulk superconductors,it is firstly important to accurately detect these voids/cracks in them.In this paper,we proposed a method for quantitatively evaluating multiple voids/cracks in bulk superconductors through the magnetic field and displacement response signals at superconductor bulk surface.The proposed method utilizes a damage index constructed from the magnetic field signals and displacement responses to identify the number and preliminary location of multiple defects.By dividing the detection area into subdomains and combining the magnetic field signals with displacement responses within each subdomain,a particle swarm algorithm was employed to evaluate the location and size parameters of the defects.In contrast to other evaluation methods using only magnetic field or displacement response signals,the combined evaluation method using both signals can identify the number of cracks effectively.Numerical studies demonstrate that the morphology of voids and cracks reconstructed using the proposed algorithm ideally matches real defects and is applicable to cases where voids and cracks coexist.This study provides a theoretical basis for the quantitative detection of voids/cracks in bulk superconductors.展开更多
Millimeter-wave radar,with advantages such as non-contact penetration detection and privacy protection,has become a promising solution for unobtrusive monitoring in the field of smart elderly care.To solve the problem...Millimeter-wave radar,with advantages such as non-contact penetration detection and privacy protection,has become a promising solution for unobtrusive monitoring in the field of smart elderly care.To solve the problem of whether there are human body in the elderly care scene,this study proposed a method for judging the presence of a human body based on adaptive dual thresholds to reduce invalid vital sign detection in an empty environment.This method used a low-frequency energy ratio as the core judgment basis.It combined adaptive thresholds to accurately judge the presence of human targets,effectively reducing false detections caused by background interference.In addition,given the defect that variational mode extraction(VME)needs to rely on manual parameter adjustment based on empirical values,the crown porcupine optimization(CPO)algorithm is introduced to optimize the VME parameters adaptively,and the optimized VME is used to reconstruct the heartbeat signal to improve the signal purity.Then,the multiple signal classification(MUSIC)algorithm was used for spectrum analysis to improve the accuracy of heart rate estimation.The results show that in the experimental judgment of personnel,the miss rate in the case of personnel presence is 2.2%,and the false alarm rate in the case of no personnel is only 3.2%;the root mean square error and mean absolute error of the proposed heart rate(HR)estimation method are reduced by 4.4 beat per minute and 3.05 beat per minute respectively compared with the traditional VME,verifying its excellence.展开更多
This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(F...This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(FD)in unstable subsystems are developed.The FD challenge is then transformed into an H∞filtering issue.Utilizing the multiple discontinuous Lyapunov function(MDLF)approach and the mode-dependent average dwell time(MDADT)method,sufficient conditions are derived to ensure stability during both fast and slow switching.Furthermore,the existence and solutions for FD filters are provided through linear matrix inequalities(LMIs).The simulation outcomes demonstrated the excellent performance of the developed method in studied cases.展开更多
基金Projects(61573380,61303185) supported by the National Natural Science Foundation of ChinaProjects(2016M592450,2017M612585) supported by the China Postdoctoral Science FoundationProjects(2016JJ4119,2017JJ3416) supported by the Hunan Provincial Natural Science Foundation of China
文摘It is easy for teenagers to view pornographic pictures on social networks. Many researchers have studied the detection of real pornographic pictures, but there are few studies on those that are artificial. In this work, we studied how to detect artificial pornographic pictures, especially when they are on social networks. The whole detection process can be divided into two stages： feature selection and picture detection. In the feature selection stage, seven types of features that favour picture detection were selected. In the picture detection stage, three steps were included. 1） In order to alleviate the imbalance in the number of artificial pornographic pictures and normal ones, the training dataset of artificial pornographic pictures was expanded. Therefore, the features which were extracted from the training dataset can also be expanded too. 2） In order to reduce the time of feature extraction, a fast method which extracted features based on the proportionally scaled picture rather than the original one was proposed. 3） Three tree models were compared and a gradient boost decision tree （GBDT） was selected for the final picture detection. Three sets of experimental results show that the proposed method can achieve better recognition precision and drastically reduce the time cost of the method.
基金Supported by Sanming Project of Medicine in Shenzhen,No.SZSM202211029。
文摘BACKGROUND Multiple endocrine neoplasias(MENs)are a group of hereditary diseases invol-ving multiple endocrine glands,and their prevalence is low.MEN type 1(MEN1)has diverse clinical manifestations,mainly involving the parathyroid glands,gastrointestinal tract,pancreas and pituitary gland,making it easy to miss the clinical diagnosis.CASE SUMMARY We present the case of a patient in whom MEN1 was detected early.A middle-aged male with recurrent abdominal pain and diarrhea was admitted to the hos-pital.Blood tests at admission revealed hypercalcemia and hypophosphatemia,and emission computed tomography of the parathyroid glands revealed a hy-perfunctioning parathyroid lesion.Gastroscopy findings suggested a duodenal bulge and ulceration.Ultrasound endoscopy revealed a hypoechoic lesion in the duodenal bulb.Further blood tests revealed elevated levels of serum gastrin.Surgery was performed,and pathological analysis of the surgical specimens revealed a parathyroid adenoma after parathyroidectomy and a neuroendocrine tumor after duodenal bulbectomy.The time from onset to the definitive diagnosis of MEN1 was only approximately 1 year.CONCLUSION For patients who present with gastrointestinal symptoms accompanied by hyper-calcemia and hypophosphatemia,clinicians need to be alert to the possibility of MEN1.
基金Supported by the National Natural Science Foun-dation of China (60006002) Natural Science Research Project of Education Department of Guangdong Province of China (02019)
文摘With the complexity of integrated circuits is continually increasing, a local defect in circuits may cause multiple faults. The behavior of a digital circuit with a multiple fault may significantly differ from that of a single fault. A new method for the detection of multiple faults in digital circuits is presented in this paper, the method is based on binary decision diagram （BDD）. First of all, the BDDs for the normal circuit and faulty circuit are built respectively. Secondly, a test BDD is obtained by the XOR operation of the BDDs corresponds to normal circuit and faulty circuit. In the test BDD, each input assignment that leads to the leaf node labeled 1 is a test vector of multiple faults. Therefore, the test set of multiple faults is generated by searching for the type of input assignments in the test BDD. Experimental results on some digital circuits show the feasibility of the approach presented in this paper.
基金Supported by the National Natural Science Foundation of China (No.60006002) Education Department of Guangdong Province of China (No. Z02019)
文摘The single fault and multiple fault detections for multiple-valued logic circuits are studied in this paper. Firstly, it is shown that the cardinality of optimal single fault test set for fanout-free m-valued circuits with n primary inputs is not more than n + 1, for linear tree circuits is two, and for multiplication modulo circuits is two if n is an odd number or if n is an even number and m ＞ 3, where the optimal test set of a circuit has minimal number of test vectors. Secondly,it is indicated that the cardinality of optimal multiple fault test set for linear tree circuits with n primary inputs is 1 + [n/(m - 1)], for multiplication modulo circuits is n+ 1, for fanout-free circuits that consist of 2-input linear tree circuits and 2-input multiplication modulo circuits is not greater than n+ 1, where [x] denotes the smallest integer greater than or equal to x. Finally,the single fault location approaches of linear tree circuits and multiplication modulo circuits are presented, and all faults in the two types of circuits can be located by using a test set with n + 1 vectors.
基金funded by the National Key R&D Program of China[2021YFC2301102]National Natural Science Foundation of China[82202593]Key R&D Program of Hebei Province[223777100D].
文摘Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.
基金supported by the National Natural Science Foundation of China (Nos. 21525523, 21722507, 21574048, 21874121)the National Basic Research Program of China (973 Program, No. 2015CB932600)+1 种基金the National Key R&D Program of China (Nos. 2017YFA020800, 2016YFF0100800)Natural Science Foundation of Zhejiang Province of China (No. LY18B050002)
文摘The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the "false positives" results caused by a single biomolecule detections easily leads to erroneous clinical diagnosis and treatment. Thus, it is important for the homogenous quantification of multiple biomolecules in not only basic research but also practical application. As a consequent, a large number of literatures have been exploited to monitor multiple biomolecules in homogenous solution, enabling facilitating the development of the disease diagnosis, treatment as well as drug discovery. One-dimensional nanomaterials and two-dimensional nanomaterials have special physical and chemical properties, such as good electrochemical properties, stable structure, large specific surface area, and biocompatibility, which are widely used in electrochemical and fluorescent detection of biomolecules. This tutorial review highlights the recent development for the detection of multiple biomolecules by using nanomaterials including one-dimensional materials(1DMs) as well as twodimensional materials(2DMs).
文摘A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave radar. This method defines a whole-peak-outlier elimination （WPOE） criterion, which is based on in-peak-samples correlation of each target echo spectra, to trim off the target signals and abnormal disturbances with great amplitude from the complex spectra. Therefore, cleaned background noise samples are obtained to improve the accuracy and reliability of noise level estimation. When the background noise is nonhomogeneous, the detection samples are limited and often occupied heavily with outliers. In this case, the problem that the detection threshold is overvalued can be solved. In applications on experimental data, it is verified that this method can reduce the miss alarm rate of signal detection effectively in multiple target situations as well as make the adaptability of the detector better.
基金supported by Scientific and Technological De-velopment Project of Shijiazhuang (20091126A)
文摘[ Objective] To develop a rapid, sensitive, specific and accurate diagnostic method for subclinical mastitis in dairy cow. [ Method] A total of 70 samples of suspected clinical mastitis cows were detected in gene level by multiple PCR. [Result] The 58 samples were positive with the developed multiple PCR method and the positive rate was 82.5% （58/70）. The 53 samples were positive with the traditional biochemical method and the positive rate was 75.5% （53/70）. As a result, the coincidence rate of both methods was 92%. [ Conclusion] The multiple PCR method is rapid and specific for the detection of pathogenic subclinical mastitis in dairy cow.
基金supported by the Science and Technology Innovation Project of Hubei Province(No.2019ACA138)the National Natural Science Foundation of China(Nos.81871732 and 81974409)。
文摘Detection of point mutations in driver genes is of great significance for the early diagnosis,treatment,and prognostic evaluation of cancer.However,current detection methods do not offer versatility,specificity,and rapid performance simultaneously.Thus,multiple mutation detection processes are necessary,which results in long processing times and high costs.In this study,we developed a thermodynamics-guided two-way interlocking DNA cascade system for universal multiplexed mutation detection(TTI-CS).This strategy is based on the DNA probe,which changes the thermodynamic balance of the DNA cascade by the designed bubble structure,thereby achieving a good distinction between mutant and wild-type DNA.The designed method greatly shortens the detection time through two-way intrusion.In addition,this method only changes two inexpensive trigger and bridge sequences,which replace the specific and expensive nucleic acid probes used in analyses based on traditional DNA probe methods,thereby enabling multiple detections.We performed the detection of synthetic single-stranded DNA for the five mutation points and successfully detected in endometrial cancer specimens.The detection limit of this method is0.1%,which better meets the needs of clinical low-abundance multiple mutation detection.Overall,TTI-CS is currently one of the best methods for detecting multiple mutation detections.
基金Sponsored by Foundation of Underwater Acous-tic Technology National Key Lab(No.51445030205ZS2301) Foundation of the Chinese Postdoctoral Science ( No.LRB00025).
文摘Either amplitude based methods or phase based methods are usually used in multibeam bathymetry system and chosen in practical measurement by ad hoc criteria. The errors of the detection are often caused by choosing wrong detection method. In this paper a modified multiple subarrays amplitude-phase united detection method is proposed , which uses both the amplitude and phase of echo from bottom.This new method not only realizes the super-wide swath coverage, but also improves the detection performance by using the phase differences among subarrays in place of phases of subarrays to estimate the phase slope image. Experimental results are also analyzed and discussed to demonstrate the effectivity of the proposed approach.
基金the National Natural Science Foundation of China(No.61873167)the Automotive Industry Science and Technology Development Foundation of Shanghai(No.1904)。
文摘Compared to 3D object detection using a single camera,multiple cameras can overcome some limitations on field-of-view,occlusion,and low detection confidence.This study employs multiple surveillance cameras and develops a cooperative 3D object detection and tracking framework by incorporating temporal and spatial information.The framework consists of a 3D vehicle detection model,cooperatively spatial-temporal relation scheme,and heuristic camera constellation method.Specifically,the proposed cross-camera association scheme combines the geometric relationship between multiple cameras and objects in corresponding detections.The spatial-temporal method is designed to associate vehicles between different points of view at a single timestamp and fulfill vehicle tracking in the time aspect.The proposed framework is evaluated based on a synthetic cooperative dataset and shows high reliability,where the cooperative perception can recall more than 66%of the trajectory instead of 11%for single-point sensing.This could contribute to full-range surveillance for intelligent transportation systems.
基金Financial support was provided by the Alzheimer’s Australia Dementia Research Foundation Scholarship Program(AAR Postgraduate Research Scholarship),Alzheimer’s Association(USA)under grant#RG1-96-005the Judith Jane Mason and Harold Stannett Williams Memorial Foundation+1 种基金The Queensland Brain Bank,part of Australian Brain Bank Networksupported by an NHMRC(Australia)Enabling Grant No.605210
文摘Synaptic dysfunction occurs early in Alzheimer＇s disease （AD） and is acknowledged as a primary pathologic target for treatment. Synaptic degeneration is the pathological feature most strongly correlated with loss of cognitive function ante mortern （Terry et al., 1991）. Synapses are heavily damaged in hippocampal and neocortical regions of AD brain, whereas motor and occipital cortices are relatively spared （Honer et al., 1992）. Despite extensive work, the molecular mechanisms underlying synaptic degeneration are largely unknown.
基金supported by the National Natural Science Foundation of China (61174121,61121003)the National High Technology Researchand Development Program of China (863 Program) (2008AA121302)+1 种基金the National Basic Research Program of China (973 Program)(2009CB724000)the Research Fund for the Doctoral Program of Higher Education of China
文摘The problem of fault detection for linear discrete timevarying systems with multiplicative noise is dealt with.By using an observer-based robust fault detection filter（FDF） as a residual generator,the design of the FDF is formulated in the framework of H ∞ filtering for a class of stochastic time-varying systems.A sufficient condition for the existence of the FDF is derived in terms of a Riccati equation.The determination of the parameter matrices of the filter is converted into a quadratic optimization problem,and an analytical solution of the parameter matrices is obtained by solving the Riccati equation.Numerical examples are given to illustrate the effectiveness of the proposed method.
文摘A number of statistical tests are proposed for the purpose of change-point detection in a general nonparametric regression model under mild conditions. New proofs are given to prove the weak convergence of the underlying processes which assume remove the stringent condition of bounded total variation of the regression function and need only second moments. Since many quantities, such as the regression function, the distribution of the covariates and the distribution of the errors, are unspecified, the results are not distribution-free. A weighted bootstrap approach is proposed to approximate the limiting distributions. Results of a simulation study for this paper show good performance for moderate samples sizes.
基金supported by the National Natural Science Foundation of China(61102158)the China Postdoctoral Science Foundation(2011M500667)
文摘A switching variability index （SVl） constant false alarm rate （CFAR） detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homogeneity in CFAR reference windows is indicated by a VI-CFAR detector, a switching- CFAR detector is introduced to optimize the performance of the VI-CFAR detector in homogeneous, multiple targets and clutter edge backgrounds. The structure and parameters selection method of the SVI-CFAR detector is presented. Comparisons with classic CFAR detectors and recently proposed detectors are also given. Theoretical analysis and simulation results show that SVICFAR detector maintains the good performance of the VI-CFAR detector in homogeneous and clutter edge backgrounds, while greatly improving the capacity of anti-multi targets.
基金funded by the Ministry of Public Security Science and Technology Program Project(No.2023LL35)the Key Laboratory of Smart Policing and National Security Risk Governance,Sichuan Province(No.ZHZZZD2302).
文摘As the use of deepfake facial videos proliferate,the associated threats to social security and integrity cannot be overstated.Effective methods for detecting forged facial videos are thus urgently needed.While many deep learning-based facial forgery detection approaches show promise,they often fail to delve deeply into the complex relationships between image features and forgery indicators,limiting their effectiveness to specific forgery techniques.To address this challenge,we propose a dual-branch collaborative deepfake detection network.The network processes video frame images as input,where a specialized noise extraction module initially extracts the noise feature maps.Subsequently,the original facial images and corresponding noise maps are directed into two parallel feature extraction branches to concurrently learn texture and noise forgery clues.An attention mechanism is employed between the two branches to facilitate mutual guidance and enhancement of texture and noise features across four different scales.This dual-modal feature integration enhances sensitivity to forgery artifacts and boosts generalization ability across various forgery techniques.Features from both branches are then effectively combined and processed through a multi-layer perception layer to distinguish between real and forged video.Experimental results on benchmark deepfake detection datasets demonstrate that our approach outperforms existing state-of-the-art methods in terms of detection performance,accuracy,and generalization ability.
基金supported by the National Natural Science Foundation of China(Grant Nos.12232005 and 12072101).
文摘Large-grain REBa_(2)Cu_(3)O_(7-δ)(REBCO,RE=rare earth)bulk superconductors offer promising magnetic field trapping capabilities due to their high critical current density,making them ideal for many important applications such as trapped field magnets.However,for such large-grain superconductor bulks,there are lots of voids and cracks forming during the process of melting preparation,and some of them can be up to hundreds of microns or even millimeters in size.Consequently,these larger size voids/cracks pose a great threat to the strength of the bulks due to the inherent brittleness of superconductor REBCO materials.In order to ensure the operational safety of related superconducting devices with bulk superconductors,it is firstly important to accurately detect these voids/cracks in them.In this paper,we proposed a method for quantitatively evaluating multiple voids/cracks in bulk superconductors through the magnetic field and displacement response signals at superconductor bulk surface.The proposed method utilizes a damage index constructed from the magnetic field signals and displacement responses to identify the number and preliminary location of multiple defects.By dividing the detection area into subdomains and combining the magnetic field signals with displacement responses within each subdomain,a particle swarm algorithm was employed to evaluate the location and size parameters of the defects.In contrast to other evaluation methods using only magnetic field or displacement response signals,the combined evaluation method using both signals can identify the number of cracks effectively.Numerical studies demonstrate that the morphology of voids and cracks reconstructed using the proposed algorithm ideally matches real defects and is applicable to cases where voids and cracks coexist.This study provides a theoretical basis for the quantitative detection of voids/cracks in bulk superconductors.
基金supported by National Natural Science Foundation of China(Nos.62320106002 and U22A2014)National Key Research and Development Program of China(No.2021YFA1401103)2022 Wuxi Taihu Talent Program:Innovative Leading Talent Team(No.1096010241230120).
文摘Millimeter-wave radar,with advantages such as non-contact penetration detection and privacy protection,has become a promising solution for unobtrusive monitoring in the field of smart elderly care.To solve the problem of whether there are human body in the elderly care scene,this study proposed a method for judging the presence of a human body based on adaptive dual thresholds to reduce invalid vital sign detection in an empty environment.This method used a low-frequency energy ratio as the core judgment basis.It combined adaptive thresholds to accurately judge the presence of human targets,effectively reducing false detections caused by background interference.In addition,given the defect that variational mode extraction(VME)needs to rely on manual parameter adjustment based on empirical values,the crown porcupine optimization(CPO)algorithm is introduced to optimize the VME parameters adaptively,and the optimized VME is used to reconstruct the heartbeat signal to improve the signal purity.Then,the multiple signal classification(MUSIC)algorithm was used for spectrum analysis to improve the accuracy of heart rate estimation.The results show that in the experimental judgment of personnel,the miss rate in the case of personnel presence is 2.2%,and the false alarm rate in the case of no personnel is only 3.2%;the root mean square error and mean absolute error of the proposed heart rate(HR)estimation method are reduced by 4.4 beat per minute and 3.05 beat per minute respectively compared with the traditional VME,verifying its excellence.
基金the National Natural Science Foundation of China(Grant Nos.62303380,62176214,62101590,62003268)the Aeronautical Science Foundation of China(Grant No.201907053001).
文摘This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(FD)in unstable subsystems are developed.The FD challenge is then transformed into an H∞filtering issue.Utilizing the multiple discontinuous Lyapunov function(MDLF)approach and the mode-dependent average dwell time(MDADT)method,sufficient conditions are derived to ensure stability during both fast and slow switching.Furthermore,the existence and solutions for FD filters are provided through linear matrix inequalities(LMIs).The simulation outcomes demonstrated the excellent performance of the developed method in studied cases.
