Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique bas...Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique based on low rank tensor approximation is proposed for multichannel monitoring signal processing and utilization.Firstly,the affinity relationship of multichannel signals can be acquired based on the clustering results of each channel signal.Wherein an affinity tensor is constructed to integrate the diverse and consistent information of the clustering information among multichannel signals.Secondly,a low-rank tensor optimization model is built and the joint affinity matrix is optimized with the assistance of the strong confidence affinity matrix.Through solving the optimization model,the fused affinity relationship graph of multichannel signals can be obtained.Finally,the multichannel fused clustering results can be acquired though the updated joint affinity relationship graph.The multichannel signal utilization examples in health state assessment with public datasets and microwave detection with actual echoes verify the advantages and effectiveness of the proposed method.展开更多
As seismic signals propagate underground,the subsurface media absorb high-frequency components,decreasing seismic resolution and limiting the identification and characterization of thin reservoirs.To address the limit...As seismic signals propagate underground,the subsurface media absorb high-frequency components,decreasing seismic resolution and limiting the identification and characterization of thin reservoirs.To address the limitation,this paper proposes a multichannel spectral fitting(MSF)method.The MSF method aims to enhance seismic resolution by considering the spectral characteristics and the correlations between adjacent seismic traces.The key to the MSF method involves utilizing the amplitude spectrum of the attenuated Ricker wavelet to construct an objective function for spectral fitting,leading to improved seismic resolution.Furthermore,the MSF method establishes the correlation between adjacent seismic traces as a constraint to stably solve the target parameters based on the entire seismic spectrum,which helps obtain horizontally consistent and more realistic seismic signals.Synthetic and field seismic examples demonstrate that the proposed method not only provides higher-resolution seismic signals but also reveals more fine details of thin reservoirs compared to the time-variant spectral whitening method.It is concluded that the MSF method is a promising tool for seismic signal processing.展开更多
Recently,Luolai Group released its Q12025 quarterly report.As a leading Chinese home textile enterprise listed on the Shenzhen Stock Exchange in 2009,the company covers the research,design,production,and sales of home...Recently,Luolai Group released its Q12025 quarterly report.As a leading Chinese home textile enterprise listed on the Shenzhen Stock Exchange in 2009,the company covers the research,design,production,and sales of home textile products,and has multiple brands covering different consumer markets.It has expanded its online and offline comprehensive multichannel sales system and is committed to creating a win-win home furnishings and textile industry ecosystem.展开更多
BACKGROUND Gastroesophageal reflux disease has been shown to contribute to allograft injury and rejection outcomes in lung transplantation through a proposed mechanism of aspiration,inflammation,and allograft injury.T...BACKGROUND Gastroesophageal reflux disease has been shown to contribute to allograft injury and rejection outcomes in lung transplantation through a proposed mechanism of aspiration,inflammation,and allograft injury.The value of pre-transplant reflux testing in predicting reduction in pulmonary function after lung transplantation is unclear.We hypothesized that increased reflux burden on pre-transplant reflux testing is associated with pulmonary function decline following lung transplant.AIM To assess the relationship between pre-transplant measures of reflux and pulmonary function decline in lung transplant recipients.METHODS This was a retrospective cohort study of lung transplant recipients who underwent pre-transplant reflux testing with 24-hour pH-impedance off acid suppression at a tertiary center in 2007-2016.Patients with pre-transplant fundoplication were excluded.Time-to-event analysis was performed using Cox proportional hazards models to assess associations between reflux measures and reduction in forced expiratory volume in 1 second(FEV1)of≥20%post-transplant.Patients not meeting endpoint were censored at time of post-transplant fundoplication,last clinic visit,or death,whichever was earliest.RESULTS Seventy subjects(58%men,mean age:56 years)met the inclusion criteria.Interstitial lung disease represented the predominant pulmonary diagnosis(40%).Baseline demographics were similar between groups and were not associated with pulmonary decline.The clinical endpoint(≥20%FEV1 decline)was reached in 18 subjects(26%).In time-to-event univariate analysis,FEV1 decline was associated with increased acid exposure time(AET)[hazard ratio(HR)=3.49,P=0.03]and increased proximal acid reflux(HR=3.34,P=0.04)with confirmation on Kaplan-Meier analysis.Multivariate analysis showed persistent association between pulmonary decline and increased AET(HR=3.37,P=0.04)when controlling for potential confounders including age,body mass index,and sex.Subgroup analysis including only patients with FEV1 decline showed that all subjects with abnormal AET progressed to bronchiolitis obliterans syndrome.CONCLUSION Increased reflux burden on pre-transplant testing was associated with significant pulmonary function decline posttransplant.Pre-transplant reflux assessment may provide clinically relevant information in the prognostication and management of transplant recipients.展开更多
A systematic investigation of the fifth-harmonic generation in H_(2)^(+),driven in the vicinity of a five-photon resonance by a linearly polarized laser field,has been carried out by numerically solving the full three...A systematic investigation of the fifth-harmonic generation in H_(2)^(+),driven in the vicinity of a five-photon resonance by a linearly polarized laser field,has been carried out by numerically solving the full three-dimensional time-dependent Schrödinger equation.We observe a pronounced enhancement of the fifth harmonic,while the intensities of the adjacent harmonics are significantly suppressed.Our analysis shows that such an enhancement of the fifth harmonic is mainly caused by the multiphoton resonance transition,as well as multichannel interference.In addition,we investigate the dependence of harmonic emission on laser intensity and molecular orientation to identify the optimal conditions for enhancing the fifth-harmonic generation.Our results provide useful insights for producing coherent ultraviolet radiation at 106 nm experimentally.展开更多
Quinoid structures are considered to be conducive to the charge transport of organic molecules,but this hypothesis is rarely proven at single-molecule level.Herein,as a proof of concept,the single-molecule conductance...Quinoid structures are considered to be conducive to the charge transport of organic molecules,but this hypothesis is rarely proven at single-molecule level.Herein,as a proof of concept,the single-molecule conductance of two furan-based isomers,3,3'-bis(4-(methylthio)phenyl)-2,2'-bifuran(2,2'-SMPBF)and 4,4'-bis(4-(methylthio)phenyl)-3,3'-bifuran(3,3'-SMPBF),is investigated by the scanning tunneling microscopy break junction(STM-BJ)technique and theoretical simulation.2,2'-SMPBF prefers to adopt a nearly planar conformation with intact alternating single and double bonds extended via2,2'-bifuran moiety and therefore exhibits goodπ-conjugation and a prominent quinoid structure.However,theπ-conjugation of 3,3'-SMPBF is interrupted due to ineffective cross-conjugation in the 3,3'-bifuran moiety,leading to the absence of a quinoid structure.2,2'-SMPBF displays switchable multiple conductances induced by the interconversion between folded and unfolded conformations and an abnormal rebound of conductance along with the increases of electrode displacement,which is demonstrated to be caused by the quinoid structure in a nearly planar conformation during the stretching process.However,3,3'-SMPBF without a quinoid structure in unfolded conformation exhibits extremely low conductance that cannot be captured in STM-BJ measurements.These results reveal the significant contribution of quinoid structure to molecular charge transport and provide valuable information on the structure-transport relationship for the design of efficient organic semiconductors.展开更多
Enhancing the ignition system performance of turbo engines is crucial,with a focus on rapidly and reliably igniting the entire combustor in low-temperature,low-pressure,high-speed inlet flow conditions.This challenge ...Enhancing the ignition system performance of turbo engines is crucial,with a focus on rapidly and reliably igniting the entire combustor in low-temperature,low-pressure,high-speed inlet flow conditions.This challenge has garnered international attention.To address the issue of reliable ignition in the combustors of advanced propulsion system,this paper proposes a Multichannel Jet Enhanced Plasma Igniter(MJEPI) and conducts comparative experimental studies with the conventional spark igniter in a component-level dual-dome swirl combustor.The ignition limit in the combustor is obtained and the ignition processes are recorded.Experimental results demonstrate that the MJEPI significantly improves the ignition performance at high altitude.Specifically,at 0 km and 6 km for ground start-up,ignition limit is extended by 36% and 29%,respectively.At 6 km and 12 km for high-altitude relight,ignition limit is extended by 32% and 21%,respectively.The maximum ignition height is increased by 2.3 km,as determined by the global equivalence ratio of 1.The primary reason for these improvements is attributed to the larger initial flame kernel with greater penetration depth generated by MJEPI,which enables it to withstand more sever conditions such as low temperature,low pressure,and poor kerosene spray quality at elevated altitudes.展开更多
Traditional deconvolution methods based on single-channel inversion do not consider the spatial structural relation between channels,and hence,they yield high-resolution results with the existing transverse inconsiste...Traditional deconvolution methods based on single-channel inversion do not consider the spatial structural relation between channels,and hence,they yield high-resolution results with the existing transverse inconsistency or discontinuity.Therefore,in this study,the local dip angle was used to obtain the structural information and construct the spatial structurally constraint operator.This operator is then introduced into multichannel deconvolution as a regularization operator to improve the resolution and maintain the transverse continuity of seismic data.Model tests and actual seismic data processing have demonstrated the effectiveness and practicability of this method.展开更多
A new method in digital hearing aids to adaptively localize the speech source in noise and reverberant environment is proposed. Based on the room reverberant model and the multichannel adaptive eigenvalue decompositi...A new method in digital hearing aids to adaptively localize the speech source in noise and reverberant environment is proposed. Based on the room reverberant model and the multichannel adaptive eigenvalue decomposition (MCAED) algorithm, the proposed method can iteratively estimate impulse response coefficients between the speech source and microphones by the adaptive subgradient projection method. Then, it acquires the time delays of microphone pairs, and calculates the source position by the geometric method. Compared with the traditional normal least mean square (NLMS) algorithm, the adaptive subgradient projection method achieves faster and more accurate convergence in a low signal-to-noise ratio (SNR) environment. Simulations for glasses digital hearing aids with four-component square array demonstrate the robust performance of the proposed method.展开更多
A multichannel matching pursuit(MMP)algorithm is proposed to decompose the one-dimensional multichannel non-stationary magnetoencephalography(MEG)signal at a single-trial level.The single-channel matching pursuit...A multichannel matching pursuit(MMP)algorithm is proposed to decompose the one-dimensional multichannel non-stationary magnetoencephalography(MEG)signal at a single-trial level.The single-channel matching pursuit(MP)linearly decomposes the signal into a set of Gabor atoms,which are adaptively chosen from an overcomplete dictionary with good time-frequency characters.The MMP is the extension of the MP,which represents multichannel signals using linear combination of Gabor atoms with the same occurrence,frequency,phase,and time width,but varying amplitude in all channels.The results demonstrate that the MMP can optimally reconstruct the original signal and automatically remove artifact noises.Moreover,the coherence between the 3D source reconstruction and the prior knowledge of psychology further suggests that the MMP is effective in MEG single-trial processing.展开更多
In this paper, the construction and performance of the microprocessor-based multi-chan-nel digital thermometric instrument together with its deisgn and fabrication are systematicallydescribed. The principle, method an...In this paper, the construction and performance of the microprocessor-based multi-chan-nel digital thermometric instrument together with its deisgn and fabrication are systematicallydescribed. The principle, method and practical softwares for the entire reference-junction com-pensation processing by microcomputer and the linearization of the characteristic ofthermocouples are also exhaustively expounded with a detailed analysis of the error existing inthe thermometric instrument. The practiced result shows that the apparatus is featured with asimple construction, high accuracy and high ability of anti-disturbance. It is proved to be ofpractical value.展开更多
The fabrication of multicomponent heterojunctions is an effective strategy to improve the performance of TiO2 based photocatalysts. We provide a new strategy for improving the charge separation and photocatalytic perf...The fabrication of multicomponent heterojunctions is an effective strategy to improve the performance of TiO2 based photocatalysts. We provide a new strategy for improving the charge separation and photocatalytic performance of ZnO /TiO2 composites by the formation of multichannel charge separated heterojunctions. ZnO /P25 composites were prepared by an incipient wetness impregnation method, and applied for the photocatalytic destruction of gaseous toluene. The ZnO /P25 composites consist of anatase TiO2(ATiO2), rutile TiO2(RTiO2) and hexagonal zincite structures. The parasitic phase of ZnO in P25 leads to the formation of ZnO(002)/ATiO2(101)/RTiO2(110) heterojunctions that exhibit enhanced light absorption and improved multichannel electron/hole separation. ZnO /P25 heterojunctions can completely oxidize toluene into CO2 and H2O under ultraviolet light irradiation at room temperature, and show enhanced photocatalytic activity in comparison with P25 owing to the efficient electron-hole separation. Such a multichannel charge separated design strategy may provide new insight into the design of highly effective photocatalysts and their potential technological applications.展开更多
When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positi...When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration.展开更多
Noise-assisted multivariate empirical mode decomposition(NA-MEMD) is suitable to analyze multichannel electroencephalography(EEG) signals of non-stationarity and non-linearity natures due to the fact that it can provi...Noise-assisted multivariate empirical mode decomposition(NA-MEMD) is suitable to analyze multichannel electroencephalography(EEG) signals of non-stationarity and non-linearity natures due to the fact that it can provide a highly localized time-frequency representation.For a finite set of multivariate intrinsic mode functions(IMFs) decomposed by NA-MEMD,it still raises the question on how to identify IMFs that contain the information of inertest in an efficient way,and conventional approaches address it by use of prior knowledge.In this work,a novel identification method of relevant IMFs without prior information was proposed based on NA-MEMD and Jensen-Shannon distance(JSD) measure.A criterion of effective factor based on JSD was applied to select significant IMF scales.At each decomposition scale,three kinds of JSDs associated with the effective factor were evaluated:between IMF components from data and themselves,between IMF components from noise and themselves,and between IMF components from data and noise.The efficacy of the proposed method has been demonstrated by both computer simulations and motor imagery EEG data from BCI competition IV datasets.展开更多
Gastroesophageal reflux disease(GERD) is a common disorder of the gastrointestinal tract. In the last few decades, new technologies have evolved and have been applied to the functional study of the esophagus, allowing...Gastroesophageal reflux disease(GERD) is a common disorder of the gastrointestinal tract. In the last few decades, new technologies have evolved and have been applied to the functional study of the esophagus, allowing for the improvement of our knowledge of the pathophysiology of GERD. High-resolution manometry(HRM) permits greater understanding of the function of the esophagogastric junction and the risks associated with hiatal hernia. Moreover, HRM has been found to be more reproducible and sensitive than conventional water-perfused manometry to detect the presence of transient lower esophageal sphincter relaxation. Esophageal 24-h p H-metry with or without combined impedance is usually performed in patients with negative endoscopy and reflux symptoms who have a poor response to anti-reflux medical therapy to assess esophageal acid exposure and symptom-reflux correlations. In particular, esophageal 24-h impedance and p H monitoring can detect acid and non-acid reflux events. Endo FLIP is a recent technique poorly applied in clinical practice, although it provides a large amount of information about the esophagogastric junction. In the coming years, laryngopharyngeal symptoms could be evaluated with up and coming non-invasive or minimally invasive techniques, such as pepsin detection in saliva or pharyngeal p H-metry. Future studies are required of these techniques to evaluate their diagnostic accuracy and usefulness, although the available data are promising.展开更多
The last five years have been an exciting time in the study of esophageal motor disorders due to the recent advances in esophageal function testing. New technologies have emerged, such as intraluminal impedance, while...The last five years have been an exciting time in the study of esophageal motor disorders due to the recent advances in esophageal function testing. New technologies have emerged, such as intraluminal impedance, while conventional techniques, such as manometry, have enjoyed many improvements due to advances in transducer technology, computerization and graphic data presentation. While these techniques provide more detailed information regarding esophageal function, our understanding of whether they can improve our ability to diagnose and treat patients more effectively is evolving. These techniques are also excellent research tools and they have added substantially to our understanding of esophageal motor function in dysphagia. This review describes the potential benefits that these new technologies may have over conventional techniques for the evaluation of dysphagia.展开更多
BACKGROUND Gene expression of inflammatory cytokines may take part in the pathophysiology of different forms of gastroesophageal reflux disease(GERD).AIM To explore gene expression of inflammatory cytokines in esophag...BACKGROUND Gene expression of inflammatory cytokines may take part in the pathophysiology of different forms of gastroesophageal reflux disease(GERD).AIM To explore gene expression of inflammatory cytokines in esophageal mucosa in patients with erosive esophagitis(EE)and non-erosive forms of GERD(NERD)and its association with data of esophageal multichannel intraluminal impedancepH(MII-pH)measurements.METHODS This was a single-center prospective study.Esophageal mucosa samples were taken from the lower part of the esophagus during endoscopy.Expression of interleukin(IL)-1β,IL-10,IL-18,tumor necrosis factorα(TNFA),toll-like receptor 4(TLR4),GATA binding protein 3(GATA3),differentiation cluster 68(CD68)andβ-2 microglobulin genes in esophageal mucosa was assessed with ImmunoQuantex assays.MII-pH measurements were performed on all the participants.Diagnosis of GERD was confirmed by the results of the MII-pH data.Based on the endoscopy,patients were allocated to the groups of EE and NERD.The control group consisted of non-symptomatic subjects with normal endoscopy and MII-pH results.We used nonparametric statistics to compare the differences between the groups.Association of expression of the mentioned genes with the results of the MII-pH data was assessed with Spearman’s rank method.RESULTS Data from 60 patients with GERD and 10 subjects of the control group were available for the analysis.Higher expression of IL-18(5.89±0.4 vs 5.28±1.1,P=0.04)and GATA3(2.92±0.86 vs 2.23±0.96,P=0.03)was found in the EE group compared to NERD.Expression of IL-1β,IL-18,TNFA,and TLR4 was lower(P<0.05)in the control group compared to EE and NERD.Esophageal acid exposure correlated with the expression of IL-1β(Spearman’s rank r=0.29),IL-18(r=0.31),TNFA(r=0.35),GATA3(r=0.34),TLR4(r=0.29),and CD68(r=0.37).Mean esophagealрНcorrelated inversely with the expression of IL-18,TNFA,GATA3,TLR4,and CD68.No association of gene expression with the number of gastroesophageal refluxes was found.CONCLUSION In patients with EE,local expression of IL-18 and GATA3 was higher compared to subjects with NERD.Esophageal acid exposure correlated directly with expression of IL-1β,IL-18,TNFA,TLR4,CD68,andβ-2 microglobulin genes.Inverse correlation was revealed between expression of IL-18,TNFA,GATA3,TLR4,and CD68 and mean esophageal pH.展开更多
AIM:To investigate the pathophysiology of functional heartburn(FH) in Japanese patients.METHODS:A total of 111 patients with proton pump inhibitor(PPI)-refractory non-erosive gastroesophageal reflux disease underwent ...AIM:To investigate the pathophysiology of functional heartburn(FH) in Japanese patients.METHODS:A total of 111 patients with proton pump inhibitor(PPI)-refractory non-erosive gastroesophageal reflux disease underwent intraesophageal pressure testing and 24-h multichannel intraluminal impedancep H(24MII-p H) testing.The patients also completed several questionnaires while they were receiving the PPI treatment, including the questionnaire for the diagnosis of reflux disease(QUEST), the frequency scale for the symptoms of gastroesophageal reflux disease(FSSG), the gastrointestinal symptoms rating scale(GSRS), SF-36, and the Cornell Medical Index(CMI).The subjects were classified into FH and endoscopy-negative reflux disease(ENRD) groups based on the Rome Ⅲ criteria.RESULTS:Thirty-three patients with esophageal motility disorder were excluded from this study, while 22 patients with abnormal esophageal acid exposure time(p H-POS) and 34 with hypersensitive esophagus(HE) were included in the ENRD group.The FH group included 22 patients with no reflux involvement.Sex, age, and body mass index did not differ significantly between the groups.The mean SF-36 values were < 50(normal) for all scales in these groups, with no significant differences.The GSRS scores in these groups were not different and showed overlap with other gastrointestinal symptoms.The QUEST and the FSSG scores did not differ significantly between the groups.Neuroticism was diagnosed using the CMI questionnaire in 17 of the 78 included subjects within the p H-POS(n=4),HE(n=8),and FH(n=5)groups,with no significant differences.CONCLUSION:Clinical characteristics of the FH and PPI-refractory ENRD groups were similar.Therefore,esophageal function should be examined via manometry and 24MII-p H testing to differentiate between them.展开更多
Objective: To analyze reflux parameters by means of combined multichannel intraluminal impedance and pH (MII-pH) monitoring in patients with gastroesophageal reflux disease (GERD) symptoms off medication, and to ...Objective: To analyze reflux parameters by means of combined multichannel intraluminal impedance and pH (MII-pH) monitoring in patients with gastroesophageal reflux disease (GERD) symptoms off medication, and to find the reflux characteristics of Chinese GERD patients and the influences of gender, age, body posture, and body mass index (BMI) on gastroesophageal reflux (GER). Methods: Between Dec. 2008 and May 2014, 125 patients with typical GERD symptoms were subjected to 24-h MII-pH monitoring. Twelve patients with normal MII-pH profiles were not considered for analysis. The reflux parameters of 113 GERD patients with abnormal Mll-pH results were analyzed. Results: (1) DeMeester scores were above the normal range in 46.90% (53/113) of GERD patients. Weakly acidic refluxes were prevalent in GERD patients, and the frequency of abnormal weakly acidic reflux was 75.22% (85/113). The frequencies of abnormal symptom index (SI) and symptom association probability (SAP) were 19.47% (22/113) and 14.16% (16/113), respectively. (2) The frequencies of DeMeester scores, the %time at pH〈4, and the numbers of reflux episodes and of long reflux episodes 〉5 min were significantly higher in male patients than in female patients. (3) The %time at pH〈4 was much higher during upright periods than during supine periods. During supine periods, 31.86% (36/113) of GERD patients had delayed bolus clearance time, compared with 19.47% (22/113) during upright periods. (4) The number of abnormal DeMeester scores, %time at pH〈4, and the number of acid refluxes during upright periods were significantly higher in obese GERD patients than in GERD patients with a normal BMI. Over- weight GERD patients also had many more acid refluxes during upright periods than GERD patients with a normal BMI Conclusions: Weakly acidic refluxes were prevalent in Chinese GERD patients. The factors male, gender, upright position, obesity (BMI〉25), but not age, may increase the frequency and severity of GER.展开更多
Integrating multisensory inputs to generate accurate perception and guide behavior is among the most critical functions of the brain.Subcortical regions such as the amygdala are involved in sensory processing includin...Integrating multisensory inputs to generate accurate perception and guide behavior is among the most critical functions of the brain.Subcortical regions such as the amygdala are involved in sensory processing including vision and audition,yet their roles in multisensory integration remain unclear.In this study,we systematically investigated the function of neurons in the amygdala and adjacent regions in integrating audiovisual sensory inputs using a semi-chronic multi-electrode array and multiple combinations of audiovisual stimuli.From a sample of 332 neurons,we showed the diverse response patterns to audiovisual stimuli and the neural characteristics of bimodal over unimodal modulation,which could be classified into four types with differentiated regional origins.Using the hierarchical clustering method,neurons were further clustered into five groups and associated with different integrating functions and sub-regions.Finally,regions distinguishing congruent and incongruent bimodal sensory inputs were identified.Overall,visual processing dominates audiovisual integration in the amygdala and adjacent regions.Our findings shed new light on the neural mechanisms of multisensory integration in the primate brain.展开更多
基金supported by Shanghai Aerospace Science and Technology Innovation Foundation(SAST2023-075)。
文摘Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique based on low rank tensor approximation is proposed for multichannel monitoring signal processing and utilization.Firstly,the affinity relationship of multichannel signals can be acquired based on the clustering results of each channel signal.Wherein an affinity tensor is constructed to integrate the diverse and consistent information of the clustering information among multichannel signals.Secondly,a low-rank tensor optimization model is built and the joint affinity matrix is optimized with the assistance of the strong confidence affinity matrix.Through solving the optimization model,the fused affinity relationship graph of multichannel signals can be obtained.Finally,the multichannel fused clustering results can be acquired though the updated joint affinity relationship graph.The multichannel signal utilization examples in health state assessment with public datasets and microwave detection with actual echoes verify the advantages and effectiveness of the proposed method.
基金supported in part by the National Natural Science Foundation of China under Grant 42174164 and Grant 41704132in part by the Key Program of the Joint Fund of the Science,Technology,and Education of Sichuan Province,China under Grant 2024NSFSC1955+4 种基金in part by the Natural Science Foundation of Sichuan Province,China under Grant 2024NSFSC0080in part by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project under Grant SKLGP2022Z011in part by the Chengdu University of Technology Postgraduate Innovative Cultivation Program:Spatiotemporal Characterization of Seismic Signals for Tight Channel Sandstone Gas Reservoirs in the Synchro-Squeezing/Extracting Transform Domain under Grant CDUT2023BJCx002in part by the Creative Research Groups of the Natural Science Foundation of Sichuan under Grant 2023NSFSC198414th Five Year Plan Major Science and Technology Project of CNOOC under Grant KJGG2022-0903.
文摘As seismic signals propagate underground,the subsurface media absorb high-frequency components,decreasing seismic resolution and limiting the identification and characterization of thin reservoirs.To address the limitation,this paper proposes a multichannel spectral fitting(MSF)method.The MSF method aims to enhance seismic resolution by considering the spectral characteristics and the correlations between adjacent seismic traces.The key to the MSF method involves utilizing the amplitude spectrum of the attenuated Ricker wavelet to construct an objective function for spectral fitting,leading to improved seismic resolution.Furthermore,the MSF method establishes the correlation between adjacent seismic traces as a constraint to stably solve the target parameters based on the entire seismic spectrum,which helps obtain horizontally consistent and more realistic seismic signals.Synthetic and field seismic examples demonstrate that the proposed method not only provides higher-resolution seismic signals but also reveals more fine details of thin reservoirs compared to the time-variant spectral whitening method.It is concluded that the MSF method is a promising tool for seismic signal processing.
文摘Recently,Luolai Group released its Q12025 quarterly report.As a leading Chinese home textile enterprise listed on the Shenzhen Stock Exchange in 2009,the company covers the research,design,production,and sales of home textile products,and has multiple brands covering different consumer markets.It has expanded its online and offline comprehensive multichannel sales system and is committed to creating a win-win home furnishings and textile industry ecosystem.
文摘BACKGROUND Gastroesophageal reflux disease has been shown to contribute to allograft injury and rejection outcomes in lung transplantation through a proposed mechanism of aspiration,inflammation,and allograft injury.The value of pre-transplant reflux testing in predicting reduction in pulmonary function after lung transplantation is unclear.We hypothesized that increased reflux burden on pre-transplant reflux testing is associated with pulmonary function decline following lung transplant.AIM To assess the relationship between pre-transplant measures of reflux and pulmonary function decline in lung transplant recipients.METHODS This was a retrospective cohort study of lung transplant recipients who underwent pre-transplant reflux testing with 24-hour pH-impedance off acid suppression at a tertiary center in 2007-2016.Patients with pre-transplant fundoplication were excluded.Time-to-event analysis was performed using Cox proportional hazards models to assess associations between reflux measures and reduction in forced expiratory volume in 1 second(FEV1)of≥20%post-transplant.Patients not meeting endpoint were censored at time of post-transplant fundoplication,last clinic visit,or death,whichever was earliest.RESULTS Seventy subjects(58%men,mean age:56 years)met the inclusion criteria.Interstitial lung disease represented the predominant pulmonary diagnosis(40%).Baseline demographics were similar between groups and were not associated with pulmonary decline.The clinical endpoint(≥20%FEV1 decline)was reached in 18 subjects(26%).In time-to-event univariate analysis,FEV1 decline was associated with increased acid exposure time(AET)[hazard ratio(HR)=3.49,P=0.03]and increased proximal acid reflux(HR=3.34,P=0.04)with confirmation on Kaplan-Meier analysis.Multivariate analysis showed persistent association between pulmonary decline and increased AET(HR=3.37,P=0.04)when controlling for potential confounders including age,body mass index,and sex.Subgroup analysis including only patients with FEV1 decline showed that all subjects with abnormal AET progressed to bronchiolitis obliterans syndrome.CONCLUSION Increased reflux burden on pre-transplant testing was associated with significant pulmonary function decline posttransplant.Pre-transplant reflux assessment may provide clinically relevant information in the prognostication and management of transplant recipients.
基金supported by the National Natural Science Foundation of China(Grant No.12264039)the Natural Science Foundation of Ningxia(Grant No.2024AAC03013)。
文摘A systematic investigation of the fifth-harmonic generation in H_(2)^(+),driven in the vicinity of a five-photon resonance by a linearly polarized laser field,has been carried out by numerically solving the full three-dimensional time-dependent Schrödinger equation.We observe a pronounced enhancement of the fifth harmonic,while the intensities of the adjacent harmonics are significantly suppressed.Our analysis shows that such an enhancement of the fifth harmonic is mainly caused by the multiphoton resonance transition,as well as multichannel interference.In addition,we investigate the dependence of harmonic emission on laser intensity and molecular orientation to identify the optimal conditions for enhancing the fifth-harmonic generation.Our results provide useful insights for producing coherent ultraviolet radiation at 106 nm experimentally.
基金financially supported by the National Natural Science Foundation of China(Nos.U23A20594,22375066 and 21788102)Guang Dong Basic and Applied Basic Research Foundation(No.2023B1515040003)。
文摘Quinoid structures are considered to be conducive to the charge transport of organic molecules,but this hypothesis is rarely proven at single-molecule level.Herein,as a proof of concept,the single-molecule conductance of two furan-based isomers,3,3'-bis(4-(methylthio)phenyl)-2,2'-bifuran(2,2'-SMPBF)and 4,4'-bis(4-(methylthio)phenyl)-3,3'-bifuran(3,3'-SMPBF),is investigated by the scanning tunneling microscopy break junction(STM-BJ)technique and theoretical simulation.2,2'-SMPBF prefers to adopt a nearly planar conformation with intact alternating single and double bonds extended via2,2'-bifuran moiety and therefore exhibits goodπ-conjugation and a prominent quinoid structure.However,theπ-conjugation of 3,3'-SMPBF is interrupted due to ineffective cross-conjugation in the 3,3'-bifuran moiety,leading to the absence of a quinoid structure.2,2'-SMPBF displays switchable multiple conductances induced by the interconversion between folded and unfolded conformations and an abnormal rebound of conductance along with the increases of electrode displacement,which is demonstrated to be caused by the quinoid structure in a nearly planar conformation during the stretching process.However,3,3'-SMPBF without a quinoid structure in unfolded conformation exhibits extremely low conductance that cannot be captured in STM-BJ measurements.These results reveal the significant contribution of quinoid structure to molecular charge transport and provide valuable information on the structure-transport relationship for the design of efficient organic semiconductors.
基金supported by the Science Center for Gas Turbine Project, China (No. P2022-B-Ⅱ-018-001)。
文摘Enhancing the ignition system performance of turbo engines is crucial,with a focus on rapidly and reliably igniting the entire combustor in low-temperature,low-pressure,high-speed inlet flow conditions.This challenge has garnered international attention.To address the issue of reliable ignition in the combustors of advanced propulsion system,this paper proposes a Multichannel Jet Enhanced Plasma Igniter(MJEPI) and conducts comparative experimental studies with the conventional spark igniter in a component-level dual-dome swirl combustor.The ignition limit in the combustor is obtained and the ignition processes are recorded.Experimental results demonstrate that the MJEPI significantly improves the ignition performance at high altitude.Specifically,at 0 km and 6 km for ground start-up,ignition limit is extended by 36% and 29%,respectively.At 6 km and 12 km for high-altitude relight,ignition limit is extended by 32% and 21%,respectively.The maximum ignition height is increased by 2.3 km,as determined by the global equivalence ratio of 1.The primary reason for these improvements is attributed to the larger initial flame kernel with greater penetration depth generated by MJEPI,which enables it to withstand more sever conditions such as low temperature,low pressure,and poor kerosene spray quality at elevated altitudes.
基金supported by the basic and forward-looking project(No.2023YQX302)。
文摘Traditional deconvolution methods based on single-channel inversion do not consider the spatial structural relation between channels,and hence,they yield high-resolution results with the existing transverse inconsistency or discontinuity.Therefore,in this study,the local dip angle was used to obtain the structural information and construct the spatial structurally constraint operator.This operator is then introduced into multichannel deconvolution as a regularization operator to improve the resolution and maintain the transverse continuity of seismic data.Model tests and actual seismic data processing have demonstrated the effectiveness and practicability of this method.
基金Supported by the National Natural Science Foundation of China (60872073)~~
文摘A new method in digital hearing aids to adaptively localize the speech source in noise and reverberant environment is proposed. Based on the room reverberant model and the multichannel adaptive eigenvalue decomposition (MCAED) algorithm, the proposed method can iteratively estimate impulse response coefficients between the speech source and microphones by the adaptive subgradient projection method. Then, it acquires the time delays of microphone pairs, and calculates the source position by the geometric method. Compared with the traditional normal least mean square (NLMS) algorithm, the adaptive subgradient projection method achieves faster and more accurate convergence in a low signal-to-noise ratio (SNR) environment. Simulations for glasses digital hearing aids with four-component square array demonstrate the robust performance of the proposed method.
基金The National Natural Science Foundation of China(No.30900356,81071135)the National High Technology Research and Development Program of China(863Program)(No.2008AA02Z410)
文摘A multichannel matching pursuit(MMP)algorithm is proposed to decompose the one-dimensional multichannel non-stationary magnetoencephalography(MEG)signal at a single-trial level.The single-channel matching pursuit(MP)linearly decomposes the signal into a set of Gabor atoms,which are adaptively chosen from an overcomplete dictionary with good time-frequency characters.The MMP is the extension of the MP,which represents multichannel signals using linear combination of Gabor atoms with the same occurrence,frequency,phase,and time width,but varying amplitude in all channels.The results demonstrate that the MMP can optimally reconstruct the original signal and automatically remove artifact noises.Moreover,the coherence between the 3D source reconstruction and the prior knowledge of psychology further suggests that the MMP is effective in MEG single-trial processing.
文摘In this paper, the construction and performance of the microprocessor-based multi-chan-nel digital thermometric instrument together with its deisgn and fabrication are systematicallydescribed. The principle, method and practical softwares for the entire reference-junction com-pensation processing by microcomputer and the linearization of the characteristic ofthermocouples are also exhaustively expounded with a detailed analysis of the error existing inthe thermometric instrument. The practiced result shows that the apparatus is featured with asimple construction, high accuracy and high ability of anti-disturbance. It is proved to be ofpractical value.
基金supported by the National Natural Science Foundation of China(21576298,21425627)the Science and Technology Plan Project of Guangdong Province(2013B090500029)+1 种基金Natural Science Foundation of Guangdong Province(2014A030313135,2014A030308012)the State Key Laboratory of Chemical Resource Engineering(CRE-2015-C-301),China~~
文摘The fabrication of multicomponent heterojunctions is an effective strategy to improve the performance of TiO2 based photocatalysts. We provide a new strategy for improving the charge separation and photocatalytic performance of ZnO /TiO2 composites by the formation of multichannel charge separated heterojunctions. ZnO /P25 composites were prepared by an incipient wetness impregnation method, and applied for the photocatalytic destruction of gaseous toluene. The ZnO /P25 composites consist of anatase TiO2(ATiO2), rutile TiO2(RTiO2) and hexagonal zincite structures. The parasitic phase of ZnO in P25 leads to the formation of ZnO(002)/ATiO2(101)/RTiO2(110) heterojunctions that exhibit enhanced light absorption and improved multichannel electron/hole separation. ZnO /P25 heterojunctions can completely oxidize toluene into CO2 and H2O under ultraviolet light irradiation at room temperature, and show enhanced photocatalytic activity in comparison with P25 owing to the efficient electron-hole separation. Such a multichannel charge separated design strategy may provide new insight into the design of highly effective photocatalysts and their potential technological applications.
基金supported by the National Scientific Foundation of China (Grant no. 41506085)the Open Foundation of the Key Laboratory of Gas Hydrate, Ministry of Land and Resources, China (Grant no. SHW [2014]-DX-12)the China Geological Survey Project (Grant no. DD20160213)
文摘When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration.
基金Projects(61201302,61372023,61671197)supported by the National Natural Science Foundation of ChinaProject(201308330297)supported by the State Scholarship Fund of ChinaProject(LY15F010009)supported by Zhejiang Provincial Natural Science Foundation,China
文摘Noise-assisted multivariate empirical mode decomposition(NA-MEMD) is suitable to analyze multichannel electroencephalography(EEG) signals of non-stationarity and non-linearity natures due to the fact that it can provide a highly localized time-frequency representation.For a finite set of multivariate intrinsic mode functions(IMFs) decomposed by NA-MEMD,it still raises the question on how to identify IMFs that contain the information of inertest in an efficient way,and conventional approaches address it by use of prior knowledge.In this work,a novel identification method of relevant IMFs without prior information was proposed based on NA-MEMD and Jensen-Shannon distance(JSD) measure.A criterion of effective factor based on JSD was applied to select significant IMF scales.At each decomposition scale,three kinds of JSDs associated with the effective factor were evaluated:between IMF components from data and themselves,between IMF components from noise and themselves,and between IMF components from data and noise.The efficacy of the proposed method has been demonstrated by both computer simulations and motor imagery EEG data from BCI competition IV datasets.
文摘Gastroesophageal reflux disease(GERD) is a common disorder of the gastrointestinal tract. In the last few decades, new technologies have evolved and have been applied to the functional study of the esophagus, allowing for the improvement of our knowledge of the pathophysiology of GERD. High-resolution manometry(HRM) permits greater understanding of the function of the esophagogastric junction and the risks associated with hiatal hernia. Moreover, HRM has been found to be more reproducible and sensitive than conventional water-perfused manometry to detect the presence of transient lower esophageal sphincter relaxation. Esophageal 24-h p H-metry with or without combined impedance is usually performed in patients with negative endoscopy and reflux symptoms who have a poor response to anti-reflux medical therapy to assess esophageal acid exposure and symptom-reflux correlations. In particular, esophageal 24-h impedance and p H monitoring can detect acid and non-acid reflux events. Endo FLIP is a recent technique poorly applied in clinical practice, although it provides a large amount of information about the esophagogastric junction. In the coming years, laryngopharyngeal symptoms could be evaluated with up and coming non-invasive or minimally invasive techniques, such as pepsin detection in saliva or pharyngeal p H-metry. Future studies are required of these techniques to evaluate their diagnostic accuracy and usefulness, although the available data are promising.
基金Supported by RO1 DC00646 (PJK & JEP) from the Public Health Service
文摘The last five years have been an exciting time in the study of esophageal motor disorders due to the recent advances in esophageal function testing. New technologies have emerged, such as intraluminal impedance, while conventional techniques, such as manometry, have enjoyed many improvements due to advances in transducer technology, computerization and graphic data presentation. While these techniques provide more detailed information regarding esophageal function, our understanding of whether they can improve our ability to diagnose and treat patients more effectively is evolving. These techniques are also excellent research tools and they have added substantially to our understanding of esophageal motor function in dysphagia. This review describes the potential benefits that these new technologies may have over conventional techniques for the evaluation of dysphagia.
基金Supported by Ministry of Science and Higher Education,No.FGMF-2022-0005 and No.0410-2020-0007。
文摘BACKGROUND Gene expression of inflammatory cytokines may take part in the pathophysiology of different forms of gastroesophageal reflux disease(GERD).AIM To explore gene expression of inflammatory cytokines in esophageal mucosa in patients with erosive esophagitis(EE)and non-erosive forms of GERD(NERD)and its association with data of esophageal multichannel intraluminal impedancepH(MII-pH)measurements.METHODS This was a single-center prospective study.Esophageal mucosa samples were taken from the lower part of the esophagus during endoscopy.Expression of interleukin(IL)-1β,IL-10,IL-18,tumor necrosis factorα(TNFA),toll-like receptor 4(TLR4),GATA binding protein 3(GATA3),differentiation cluster 68(CD68)andβ-2 microglobulin genes in esophageal mucosa was assessed with ImmunoQuantex assays.MII-pH measurements were performed on all the participants.Diagnosis of GERD was confirmed by the results of the MII-pH data.Based on the endoscopy,patients were allocated to the groups of EE and NERD.The control group consisted of non-symptomatic subjects with normal endoscopy and MII-pH results.We used nonparametric statistics to compare the differences between the groups.Association of expression of the mentioned genes with the results of the MII-pH data was assessed with Spearman’s rank method.RESULTS Data from 60 patients with GERD and 10 subjects of the control group were available for the analysis.Higher expression of IL-18(5.89±0.4 vs 5.28±1.1,P=0.04)and GATA3(2.92±0.86 vs 2.23±0.96,P=0.03)was found in the EE group compared to NERD.Expression of IL-1β,IL-18,TNFA,and TLR4 was lower(P<0.05)in the control group compared to EE and NERD.Esophageal acid exposure correlated with the expression of IL-1β(Spearman’s rank r=0.29),IL-18(r=0.31),TNFA(r=0.35),GATA3(r=0.34),TLR4(r=0.29),and CD68(r=0.37).Mean esophagealрНcorrelated inversely with the expression of IL-18,TNFA,GATA3,TLR4,and CD68.No association of gene expression with the number of gastroesophageal refluxes was found.CONCLUSION In patients with EE,local expression of IL-18 and GATA3 was higher compared to subjects with NERD.Esophageal acid exposure correlated directly with expression of IL-1β,IL-18,TNFA,TLR4,CD68,andβ-2 microglobulin genes.Inverse correlation was revealed between expression of IL-18,TNFA,GATA3,TLR4,and CD68 and mean esophageal pH.
文摘AIM:To investigate the pathophysiology of functional heartburn(FH) in Japanese patients.METHODS:A total of 111 patients with proton pump inhibitor(PPI)-refractory non-erosive gastroesophageal reflux disease underwent intraesophageal pressure testing and 24-h multichannel intraluminal impedancep H(24MII-p H) testing.The patients also completed several questionnaires while they were receiving the PPI treatment, including the questionnaire for the diagnosis of reflux disease(QUEST), the frequency scale for the symptoms of gastroesophageal reflux disease(FSSG), the gastrointestinal symptoms rating scale(GSRS), SF-36, and the Cornell Medical Index(CMI).The subjects were classified into FH and endoscopy-negative reflux disease(ENRD) groups based on the Rome Ⅲ criteria.RESULTS:Thirty-three patients with esophageal motility disorder were excluded from this study, while 22 patients with abnormal esophageal acid exposure time(p H-POS) and 34 with hypersensitive esophagus(HE) were included in the ENRD group.The FH group included 22 patients with no reflux involvement.Sex, age, and body mass index did not differ significantly between the groups.The mean SF-36 values were < 50(normal) for all scales in these groups, with no significant differences.The GSRS scores in these groups were not different and showed overlap with other gastrointestinal symptoms.The QUEST and the FSSG scores did not differ significantly between the groups.Neuroticism was diagnosed using the CMI questionnaire in 17 of the 78 included subjects within the p H-POS(n=4),HE(n=8),and FH(n=5)groups,with no significant differences.CONCLUSION:Clinical characteristics of the FH and PPI-refractory ENRD groups were similar.Therefore,esophageal function should be examined via manometry and 24MII-p H testing to differentiate between them.
文摘Objective: To analyze reflux parameters by means of combined multichannel intraluminal impedance and pH (MII-pH) monitoring in patients with gastroesophageal reflux disease (GERD) symptoms off medication, and to find the reflux characteristics of Chinese GERD patients and the influences of gender, age, body posture, and body mass index (BMI) on gastroesophageal reflux (GER). Methods: Between Dec. 2008 and May 2014, 125 patients with typical GERD symptoms were subjected to 24-h MII-pH monitoring. Twelve patients with normal MII-pH profiles were not considered for analysis. The reflux parameters of 113 GERD patients with abnormal Mll-pH results were analyzed. Results: (1) DeMeester scores were above the normal range in 46.90% (53/113) of GERD patients. Weakly acidic refluxes were prevalent in GERD patients, and the frequency of abnormal weakly acidic reflux was 75.22% (85/113). The frequencies of abnormal symptom index (SI) and symptom association probability (SAP) were 19.47% (22/113) and 14.16% (16/113), respectively. (2) The frequencies of DeMeester scores, the %time at pH〈4, and the numbers of reflux episodes and of long reflux episodes 〉5 min were significantly higher in male patients than in female patients. (3) The %time at pH〈4 was much higher during upright periods than during supine periods. During supine periods, 31.86% (36/113) of GERD patients had delayed bolus clearance time, compared with 19.47% (22/113) during upright periods. (4) The number of abnormal DeMeester scores, %time at pH〈4, and the number of acid refluxes during upright periods were significantly higher in obese GERD patients than in GERD patients with a normal BMI. Over- weight GERD patients also had many more acid refluxes during upright periods than GERD patients with a normal BMI Conclusions: Weakly acidic refluxes were prevalent in Chinese GERD patients. The factors male, gender, upright position, obesity (BMI〉25), but not age, may increase the frequency and severity of GER.
基金supported by the National Natural Science Foundation of China(U20A2017 and 31830037)Guangdong Basic and Applied Basic Research Foundation(2020A1515010785,2020A1515111118,and 2022A1515010134)+5 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2017120)the Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions(NYKFKT2019009)Shenzhen Technological Research Center for Primate Translational Medicine(F-2021-Z99-504979)the Strategic Research Program of the Chinese Academy of Sciences(XDBS01030100 and XDB32010300)Scientific and Technological Innovation 2030(2021ZD0204300)the Fundamental Research Funds for the Central Universities.
文摘Integrating multisensory inputs to generate accurate perception and guide behavior is among the most critical functions of the brain.Subcortical regions such as the amygdala are involved in sensory processing including vision and audition,yet their roles in multisensory integration remain unclear.In this study,we systematically investigated the function of neurons in the amygdala and adjacent regions in integrating audiovisual sensory inputs using a semi-chronic multi-electrode array and multiple combinations of audiovisual stimuli.From a sample of 332 neurons,we showed the diverse response patterns to audiovisual stimuli and the neural characteristics of bimodal over unimodal modulation,which could be classified into four types with differentiated regional origins.Using the hierarchical clustering method,neurons were further clustered into five groups and associated with different integrating functions and sub-regions.Finally,regions distinguishing congruent and incongruent bimodal sensory inputs were identified.Overall,visual processing dominates audiovisual integration in the amygdala and adjacent regions.Our findings shed new light on the neural mechanisms of multisensory integration in the primate brain.