Electroencephalography(EEG)analysis extracts critical information from brain signals,enabling brain disease diagnosis and providing fundamental support for brain–computer interfaces.However,performing an artificial i...Electroencephalography(EEG)analysis extracts critical information from brain signals,enabling brain disease diagnosis and providing fundamental support for brain–computer interfaces.However,performing an artificial intelligence analysis of EEG signals with high energy efficiency poses significant challenges for electronic processors on edge computing devices,especially with large neural network models.Herein,we propose an EEG opto-processor based on diffractive photonic computing units(DPUs)to process extracranial and intracranial EEG signals effectively and to detect epileptic seizures.The signals of the EEG channels within a second-time window are optically encoded as inputs to the constructed diffractive neural networks for classification,which monitors the brain state to identify symptoms of an epileptic seizure.We developed both free-space and integrated DPUs as edge computing systems and demonstrated their applications for real-time epileptic seizure detection using benchmark datasets,that is,the Children’s Hospital Boston(CHB)–Massachusetts Institute of Technology(MIT)extracranial and Epilepsy-iEEG-Multicenter intracranial EEG datasets,with excellent computing performance results.Along with the channel selection mechanism,both numerical evaluations and experimental results validated the sufficiently high classification accuracies of the proposed opto-processors for supervising clinical diagnosis.Our study opens a new research direction for utilizing photonic computing techniques to process large-scale EEG signals and promote broader applications.展开更多
In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which c...In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process.As a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell.The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment.In addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber.The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials.This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.展开更多
objective:Two cycles of induction chemotherapy(IC)followed by 2 cycles of platinum-based concurrent chemoradiotherapy(CCRT)(2IC+2CCRT)for locoregionally advanced nasopharyngeal carcinoma(LA-NPC)is widely adopted but n...objective:Two cycles of induction chemotherapy(IC)followed by 2 cycles of platinum-based concurrent chemoradiotherapy(CCRT)(2IC+2CCRT)for locoregionally advanced nasopharyngeal carcinoma(LA-NPC)is widely adopted but not evidence-confirmed.This study aimed to determine the clinical value of 2IC+2CCRT regarding efficacy,toxicity and cost-effectiveness.Methods:This real-world study from two epidemic centers used propensity score matching(PSM)and inverse probability of treatment weighting(IPTW)analyses.The enrolled patients were divided into three groups based on treatment modality:Group A(2IC+2CCRT),Group B(3IC+2CCRT or 2IC+3CCRT)and Group C(3IC+3CCRT).Long-term survival,acute toxicities and cost-effectiveness were compared among the groups.We developed a prognostic model dividing the population into high-and low-risk cohorts,and survivals including overall survival(OS),progression-free survival(PFS),distant metastasis-free survival(DMFS)and locoregional relapse-free survival(LRRFS)were compared among the three groups according to certain risk stratifications.Results:Of 4,042 patients,1,175 were enrolled,with 660,419,and 96 included in Groups A,B and C,respectively.Five-year survivals were similar among the three groups after PSM and confirmed by IPTW.Grade 3-4 neutropenia and leukocytopenia were significantly higher in Groups C and B than in Group A(52.1%vs.41.5%vs.25.2%;41.7%vs.32.7%vs.25.0%)as were grade 3-4 nausea/vomiting and oral mucositis(29.2%vs.15.0%vs.6.1%;32.3%vs.25.3%vs.18.0%).Cost-effective analysis suggested that 2IC+2CCRT was the least expensive,while the health benefits were similar to those of the other groups.Further exploration showed that 2IC+2CCRT tended to be associated with a shorter PFS in high-risk patients,while 3IC+3CCRT potentially contributed to poor PFS in low-risk individuals,mainly reflected by LRRFS.Conclusions:In LA-NPC patients,2IC+2CCRT was the optimal choice regarding efficacy,toxicity and costeffectiveness;however,2IC+2CCRT and 3IC+3CCRT probably shortened LRRFS in high-and low-risk populations,respectively.展开更多
AIM:To compare postoperative complications and prognosis of esophageal squamous cell carcinoma patients treated with different routes of reconstruction. METHODS:After obtaining approval from the Medical Ethics Committ...AIM:To compare postoperative complications and prognosis of esophageal squamous cell carcinoma patients treated with different routes of reconstruction. METHODS:After obtaining approval from the Medical Ethics Committee of the Sun Yat-Sen University Cancer Center, we retrospectively reviewed data from 306 consecutive patients with histologically diagnosed esophageal squamous cell carcinoma who were treated between 2001 and 2011. All patients underwent radical McKeown-type esophagectomy with at least two-field lymphadenectomy. Regular follow-up was performed in our outpatient department. Postoperative complica-tions and long-term survival were analyzed by treatment modality, baseline patient characteristics, and operative procedure. Data from patients treated via the retrosternal and posterior mediastinal routes were compared. RESULTS:The posterior mediastinal and retrosternal reconstruction routes were employed in 120 and 186 patients, respectively. Pulmonary complications were the most common complications experienced during the postoperative period (46.1% of all patients; 141/306). Compared to the retrosternal route, the posterior mediastinal reconstruction route was associated with a lower incidence of anastomotic stricture (15.8% vs 27.4%, P = 0.018) and less surgical bleeding (242.8 ± 114.2 mL vs 308.2 ± 168.4 mL, P < 0.001). The median survival time was 26.8 mo (range:1.6-116.1 mo). Upon uni/multivariate analysis, a lower preoperative albumin level (P = 0.009) and a more advanced pathological stage (pT; P = 0.006; pN; P < 0.001) were identified as independent factors predicting poor prognosis. The reconstruction route did not influence prognosis (P = 0.477). CONCLUSION:The posterior mediastinal route of reconstruction reduces incidence of postoperative complications but does not affect survival. This route is recommended for resectable esophageal squamous cell carcinoma.展开更多
The management of postoperative leaks into the mediastinum after esophagectomy remains a challenge. We describe our clinical management of this complication through endoscopic transluminal drainage. Between 2008 and 2...The management of postoperative leaks into the mediastinum after esophagectomy remains a challenge. We describe our clinical management of this complication through endoscopic transluminal drainage. Between 2008 and 2011, 4 patients with esophageal squamous cell carcinoma (ESCC) who underwent McKeown-type esophagectomy with two-field lymphadenectomy experienced complicated anastomotic fistulae in the presence of superior mediastinal sepsis. All 4 patients underwent endoscopic transluminal drainage, and all survived. The mean healing period was 50 days (range, 31 to 58 days), the mean stay in the intensive care unit was 7.3 days (range, 1 to 18 days), and the mean hospital stay was 64.5 days (range, 49 to 70 days). Endoscopically guided transluminal drainage should be considered for ESCC patients with superior mediastinal fistulae after esophagectomy.展开更多
AIM: To evaluate whether preoperative mean corpuscular volume (MCV) is a prognostic indicator in patients with resectable esophageal squamous cell carcinoma (ESCC). METHODS: A total of 298 consecutive, prospectively e...AIM: To evaluate whether preoperative mean corpuscular volume (MCV) is a prognostic indicator in patients with resectable esophageal squamous cell carcinoma (ESCC). METHODS: A total of 298 consecutive, prospectively enrolled patients with histologically diagnosed ESCC who underwent surgery with curative intent from 2001 to 2011 were retrospectively evaluated. Patients were excluded if they had previous malignant disease, distant metastasis at the time of primary treatment, a history of neoadjuvant treatment, had undergone nonradical resection, or had died of a non-tumor-associated cause. Survival status was verified in September 2011. Pathological staging was performed based on the 2010 American Joint Committee on Cancer criteria. Preoperative MCV was obtained from blood counts performed routinely within 7 d prior to surgery. Receiver operating characteristic (ROC) curve analysis was used to determine a cutoff for preoperative MCV. RESULTS: The 298 patients consisted of 230 males and 68 females, with a median follow-up of 30.1 mo. ROC analysis showed an optimal cutoff for preoperative MCV of 95.6 fl. Fifty-nine patients (19.8%) had high (> 95.6 fl) and 239 (80.2%) had low (≤ 95.6 fl) preoperative MCV. Preoperative MCV was significantly associated with gender (P=0.003), body mass index (P=0.017), and preoperative red blood cell count (P<0.001). The predicted 1-, 3and 5-year overall survival (OS) rates were 72%, 60% and 52%, respectively. Median OS was significantly longer in patients with low than with high preoperative MCV (27.5 mo vs 19.4 mo, P<0.001). Multivariate analysis showed that advanced pT (P=0.018) and pN (P<0.001) stages, upper thoracic location (P=0.010), lower preoperative albumin concentration (P=0.002), and high preoperative MCV (P=0.001) were negative prognostic factors in patients with ESCC. Preoperative MCV also stratified OS in patients with T3, N1-N3, G2-G3 and stage Ⅲ tumors. CONCLUSION: Preoperative MCV is a prognostic factor in patients with ESCC.展开更多
Three-dimensional(3 D)topological insulators(TIs)are candidate materials for various electronic and spintronic devices due to their strong spin-orbit coupling and unique surface electronic structure.Rapid,low-cost pre...Three-dimensional(3 D)topological insulators(TIs)are candidate materials for various electronic and spintronic devices due to their strong spin-orbit coupling and unique surface electronic structure.Rapid,low-cost preparation of large-area TI thin films compatible with conventional semiconductor technology is the key to the practical applications of TIs.Here we show that wafer-sized Bi2Te3 family TI and magnetic TI films with decent quality and well-controlled composition and properties can be prepared on amorphous SiO2/Si substrates by magnetron cosputtering.The SiO2/Si substrates enable us to electrically tune(Bi1-xSbx)2Te3 and Cr-doped(Bi1-xSbx)2 Te3 TI films between p-type and n-type behavior and thus study the phenomena associated with topological surface states,such as the quantum anomalous Hall effect(QAHE).This work significantly facilitates the fabrication of TI-based devices for electronic and spintronic applications.展开更多
Background Free-viewpoint video(FVV)is processed video content in which viewers can freely select the viewing position and angle.FVV delivers an improved visual experience and can also help synthesize special effects ...Background Free-viewpoint video(FVV)is processed video content in which viewers can freely select the viewing position and angle.FVV delivers an improved visual experience and can also help synthesize special effects and virtual reality content.In this paper,a complete FVV system is proposed to interactively control the viewpoints of video relay programs through multimedia terminals such as computers and tablets.Methods The hardware of the FVV generation system is a set of synchronously controlled cameras,and the software generates videos in novel viewpoints from the captured video using view interpolation.The interactive interface is designed to visualize the generated video in novel viewpoints and enable the viewpoint to be changed interactively.Results Experiments show that our system can synthesize plausible videos in intermediate viewpoints with a view range of up to 180°.展开更多
Lens-free holographic microscopy could achieve both improved resolution and field of view(FOV), which has huge potential applications in biomedicine, fluid mechanics and soft matter physics. Unfortunately, due to the ...Lens-free holographic microscopy could achieve both improved resolution and field of view(FOV), which has huge potential applications in biomedicine, fluid mechanics and soft matter physics. Unfortunately, due to the limited sensor pixel size, target objects could not be located to a satisfactory level. Recent studies have shown that electromagnetic scattering can be fitted to digital holograms to obtain the 3 D positions of isolated colloidal spheres with nanometer precision and millisecond temporal resolution. Here, we describe a lens-free holographic imaging technique that fits multi-sphere superposition scattering to digital holograms to obtain in situ particle position and model parameters: size and refractive index of colloidal spheres. We show that the proposed method can be utilized to analyze the location and character of colloidal particles under large FOV with high density.展开更多
To improve the selective separation performance of silica nanofibers(SiO_(2)NFs)for cesium ions(Cs+)and overcome the defects of Prussian blue nanoparticles(PB NPs),PB/SiO_(2)-NH_(2)NFs were prepared to remove Cs^(+)fr...To improve the selective separation performance of silica nanofibers(SiO_(2)NFs)for cesium ions(Cs+)and overcome the defects of Prussian blue nanoparticles(PB NPs),PB/SiO_(2)-NH_(2)NFs were prepared to remove Cs^(+)from water.Among them,3-aminopropyltriethoxysilane(APTES)underwent an alkylation reaction with SiO_(2),resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO_(2)NFs.Meanwhile,the amino functional groups in APTES combined with Fe3+and then reacted with Fe2+to form PB NPs,which anchored firmly on the aminoated SiO_(2)NFs surface.In our experiment,the maxi-mumadsorption capacity of PB/SiO_(2)-NH_(2)NFs was 111.38 mg/g,which was 31.5mg/g higher than that of SiO_(2)NFs.At the same time,after the fifth cycle,the removal rate of Cs^(+)by PB/SiO_(2)-NH_(2)NFs adsorbent was 75.36%±3.69%.In addition,the adsorption isotherms and adsorption kinetics of PB/SiO_(2)-NH_(2)NFs were combined with the Freundlich model and the quasi-two-stage fitting model,respectively.Further mechanism analysis showed that the bond between PB/SiO_(2)-NH_(2)NFs and Cs^(+)was mainly a synergistic action of ion exchange,electrostatic adsorption and membrane separation.展开更多
An efficient sustainable and scalable strategy for the synthesis of porous cobalt/nitrogen co-doped carbons(Co@NCs) via pyrolysis of aniline-modified ZIFs,has been demonstrated.Aniline can coordinate and absorb on the...An efficient sustainable and scalable strategy for the synthesis of porous cobalt/nitrogen co-doped carbons(Co@NCs) via pyrolysis of aniline-modified ZIFs,has been demonstrated.Aniline can coordinate and absorb on the surface of ZIF(ZIF-CoZn3-PhA),accelerate the precipitation of ZIFs,thus resulting in smaller ZIF particle size.Meanwhile,the aniline on the surface of ZIF-CoZn3-PhA promotes the formation of the protective carbon shell and smaller Co nanoparticles,and increases nitrogen content of the catalyst.Because of these prope rties of Co@NC-PhA-3,the oxidative esterification of 5-hydroxymethylfurfural can be carried out under ambient conditions.According to our experimental and computational results,a synergistic catalytic effect between CoNx sites and Co nanoparticles has been established,in which both Co nanoparticles and CoNx can activate O2 while Co nanoparticles bind and oxidize HMF.Moreover,the formation and release of active oxygen species in CoNx sites are reinfo rced by the electronic interaction between Co nanoparticles and CoNx.展开更多
With an urgent demand of energy efficientcoatings for building fenestrations, vanadium dioxide（VO2）-based thermochromic smart coatings have beenwidely investigated due to the reversible phase transition ofVO2 at a c...With an urgent demand of energy efficientcoatings for building fenestrations, vanadium dioxide（VO2）-based thermochromic smart coatings have beenwidely investigated due to the reversible phase transition ofVO2 at a critical transition temperature of 68 ℃, which isaccompanied by the modulation of solar irradiation, espe-cially in the near-infrared region. As for commercialapplications in our daily life, there are still some obstaclesfor VO2-based smart coatings, such as the high phasetransition temperature, optical properties （luminous trans-mittance and solar modulation ability）, environmental sta-bility in a long-time period, as well as mass production. Inthis review, recent progress of thermochromic smart coat-ings to solve above obstacles has been surveyed. Mean-while, future development trends have also been given topromote the goal of commercial production of VO2 smartcoatings.展开更多
Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generatio...Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generation communication and biomedical imaging in the terahertz(THz)range.However,most current THz SLMs are adapted from optical alternatives that still need improvement in terms of uniformity,speed,and bandwidth.Here,we designed,fabricated,and characterized an 8×8THz SLM based on tunable liquid crystal metamaterial absorbers for THz single-pixel compressive imaging.We demonstrated dual-color compressive sensing(CS)imaging for dispersive objects utilizing the large frequency shift controlled by an external electric field.We developed auto-calibrated compressive sensing(ACS)algorithm to mitigate the impact of the spatially nonuniform THz incident beam and pixel modulation,which significantly improves the fidelity of reconstructed images.Furthermore,the complementary modulation at two absorption frequencies enables Hadamard masks with negative element values to be realized by frequency-switching,thereby halving the imaging time.The demonstrated imaging system paves a new route for THz single-pixel multispectral imaging with high reliability and low cost.展开更多
The prior knowledge is the significant supple- ment to image-based 3D modeling algorithms for refining the fragile consistency-based stereo. In this paper, we review the image-based 3D modeling problem according to pr...The prior knowledge is the significant supple- ment to image-based 3D modeling algorithms for refining the fragile consistency-based stereo. In this paper, we review the image-based 3D modeling problem according to prior cate- gories, i.e., classical priors and specific priors. The classical priors including smoothness, silhouette and illumination are well studied for improving the accuracy and robustness of the 3D reconstruction. In recent years, various specific priors which take advantage of Manhattan rule, geometry template and trained category features have been proposed to enhance the modeling performance. The advantages and limitations of both kinds of priors are discussed and evaluated in the paper. Finally, we discuss the trend and challenges of the prior studies in the future.展开更多
Micro-endoscopes are widely used for detecting and visualizing hard-to-reach areas of the human body and for in vivo observation of animals.A micro-endoscope that can realize 3D imaging at the camera framerate could b...Micro-endoscopes are widely used for detecting and visualizing hard-to-reach areas of the human body and for in vivo observation of animals.A micro-endoscope that can realize 3D imaging at the camera framerate could benefit various clinical and biological applications.In this work,we report the development of a compact light-field micro-endoscope(LFME)that can obtain snapshot 3D fluorescence imaging,by jointly using a single-mode fiber bundle and a small-size light-field configuration.To demonstrate the real imaging performance of our method,we put a resolution chart in different z positions and capture the z-stack images successively for reconstruction,achieving 333-μm-diameter field of view,24μm optimal depth of field,and up to 3.91μm spatial resolution near the focal plane.We also test our method on a human skin tissue section and He La cells.Our LFME prototype provides epi-fluorescence imaging ability with a relatively small(2-mm-diameter)imaging probe,making it suitable for in vivo detection of brain activity and gastrointestinal diseases of animals.展开更多
Oxygen-containing rare-earth metal hydride YH_xO_y,is a newly found photochromic material showing fast photoresponse.While its preparation method,optical properties and structural features have been studied extensivel...Oxygen-containing rare-earth metal hydride YH_xO_y,is a newly found photochromic material showing fast photoresponse.While its preparation method,optical properties and structural features have been studied extensively,the photochromic mechanism in YH_xO_yremains unknown Here,using excited-state molecular dynamics simulation based on the recently developed real-time time-dependent density functional theory(RT-TDDFT)method,we study the photochemical reactions in YH_xO_y.We find that under photoexcitation,dihydrogen defects are formed within 100 fs.The dihydrogen defect behaves as a shallow donor and renders the material strongly n-type doped,which could be responsible for the photochromic effect observed in YH_xO_y.We also find that oxygen concentration affects the metastability of the dihydrogen species,meaning that the energy barrier for the dihydrogen to dissociate is related to the oxygen concentration The highest barrier of 0.28 eV is found in our model with O/Y=1:8.If the oxygen concentration is too low,the dihydrogen will quickly dissociate when the excitation is turned off.If the oxygen concentration is too high,the dihydrogen dissociates even when the excitation is still on.展开更多
The catalysis of Au thin film could be improved by fabrication of array structures in large area.In this work,nanoimprint lithography has been developed tofabricate flexible Au micro-array(MA)electrodes with~100%cover...The catalysis of Au thin film could be improved by fabrication of array structures in large area.In this work,nanoimprint lithography has been developed tofabricate flexible Au micro-array(MA)electrodes with~100%coverage.Advanced electron microscopy characterisations have directly visualised the atomic-scale three-dimensional(3D)nanostructures with a maximum depth of 6 atomic layers.In-situ observation unveils the crystal growth in the form of twinning.High double layer capacitance brings about large number of active sites on the Au thin film and has a logarithmic relationship with mesh grade.Electrochemistry testing shows that the Au MAs perform much better ethanol oxidation reaction than the planar sample;MAs with higher mesh grade have a greater active site utilisation ratio(ASUR),which is important to build electrochemical double layer for efficient charge transfer.Further improvement on ASUR is expected for greater electrocatalytic performance and potential application in direct ethanol fuel cell.展开更多
Switchable mirrors based on magnesium-nickel alloy thin films capped with catalytic Pd-Ni alloy thin films were prepared by a DC magnetron sputtering method. Their composition, structure and surface morphology were st...Switchable mirrors based on magnesium-nickel alloy thin films capped with catalytic Pd-Ni alloy thin films were prepared by a DC magnetron sputtering method. Their composition, structure and surface morphology were studied by XPS, XRD and AFM. Herein, the optical switching properties and durability of the switchable mirrors were investigated by varying the Ni content in the Pd-Ni alloys. Comparing pure Pd catalyst with Pd-Ni top-capped switchable mirrors, the latter show better hydrogenation and dehydrogenation kinetics, and the speed of hydrogen desorption is obviously improved with increasing Ni content in the Pd-Ni alloy. The Pd-Ni capped switchable mirrors also have better optical switching durability. The catalytic Pd layer with the addition of Ni does not influence the transmittance （hydride state） and reflectance （metallic state） of the switchable mirrors. In addition, replacing Pd with Pd-Ni alloy decreases the cost of the switchable mirrors： employing nickel in the alloy Pd89.2Ni10.8 can save about 11% use of Pd. Therefore, the Pd-Ni alloy can provide a cheaper catalytic thin film, and it is expected to have applications in energy-saving windows, hydrogen sensors and hydrogen storage materials.展开更多
Compared with conventional cameras, spectral imagers provide many more features in the spectral do- main. They have been used in various fields such as material identification, remote sensing, precision agriculture, a...Compared with conventional cameras, spectral imagers provide many more features in the spectral do- main. They have been used in various fields such as material identification, remote sensing, precision agriculture, and surveillance. Traditional imaging spectrometers use generally scanning systems. They cannot meet the demands of dynamic scenarios. This limits the practical applications for spectral imaging. Recently, with the rapid development in computational photography theory and semiconductor techniques, spectral video acquisition has become feasible. This paper aims to offer a review of the state-of-the-art spectral imaging technologies, especially those capable of capturing spectral videos. Finally, we evaluate the performances of the existing spectral acquisition systems and discuss the trends for future work.展开更多
基金supported by the National Major Science and Technology Projects of China(2021ZD0109902 and 2020AA0105500)the National Natural Science Fundation of China(62275139 and 62088102)the Tsinghua University Initiative Scientific Research Program.
文摘Electroencephalography(EEG)analysis extracts critical information from brain signals,enabling brain disease diagnosis and providing fundamental support for brain–computer interfaces.However,performing an artificial intelligence analysis of EEG signals with high energy efficiency poses significant challenges for electronic processors on edge computing devices,especially with large neural network models.Herein,we propose an EEG opto-processor based on diffractive photonic computing units(DPUs)to process extracranial and intracranial EEG signals effectively and to detect epileptic seizures.The signals of the EEG channels within a second-time window are optically encoded as inputs to the constructed diffractive neural networks for classification,which monitors the brain state to identify symptoms of an epileptic seizure.We developed both free-space and integrated DPUs as edge computing systems and demonstrated their applications for real-time epileptic seizure detection using benchmark datasets,that is,the Children’s Hospital Boston(CHB)–Massachusetts Institute of Technology(MIT)extracranial and Epilepsy-iEEG-Multicenter intracranial EEG datasets,with excellent computing performance results.Along with the channel selection mechanism,both numerical evaluations and experimental results validated the sufficiently high classification accuracies of the proposed opto-processors for supervising clinical diagnosis.Our study opens a new research direction for utilizing photonic computing techniques to process large-scale EEG signals and promote broader applications.
基金the National Natural Science Foundation of China(52102372,52162007,52163032)China Postdoctoral Science Foundation(2022M712321)the Jiangsu Province Postdoctoral Research Funding Program(2021K473C).
文摘In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process.As a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell.The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment.In addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber.The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials.This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.
基金supported by grants from the National Natural Science Foundation of China(No.81872375 and 82172863)the Natural Science Foundation of Guangdong Province(No.2021A1515010118).
文摘objective:Two cycles of induction chemotherapy(IC)followed by 2 cycles of platinum-based concurrent chemoradiotherapy(CCRT)(2IC+2CCRT)for locoregionally advanced nasopharyngeal carcinoma(LA-NPC)is widely adopted but not evidence-confirmed.This study aimed to determine the clinical value of 2IC+2CCRT regarding efficacy,toxicity and cost-effectiveness.Methods:This real-world study from two epidemic centers used propensity score matching(PSM)and inverse probability of treatment weighting(IPTW)analyses.The enrolled patients were divided into three groups based on treatment modality:Group A(2IC+2CCRT),Group B(3IC+2CCRT or 2IC+3CCRT)and Group C(3IC+3CCRT).Long-term survival,acute toxicities and cost-effectiveness were compared among the groups.We developed a prognostic model dividing the population into high-and low-risk cohorts,and survivals including overall survival(OS),progression-free survival(PFS),distant metastasis-free survival(DMFS)and locoregional relapse-free survival(LRRFS)were compared among the three groups according to certain risk stratifications.Results:Of 4,042 patients,1,175 were enrolled,with 660,419,and 96 included in Groups A,B and C,respectively.Five-year survivals were similar among the three groups after PSM and confirmed by IPTW.Grade 3-4 neutropenia and leukocytopenia were significantly higher in Groups C and B than in Group A(52.1%vs.41.5%vs.25.2%;41.7%vs.32.7%vs.25.0%)as were grade 3-4 nausea/vomiting and oral mucositis(29.2%vs.15.0%vs.6.1%;32.3%vs.25.3%vs.18.0%).Cost-effective analysis suggested that 2IC+2CCRT was the least expensive,while the health benefits were similar to those of the other groups.Further exploration showed that 2IC+2CCRT tended to be associated with a shorter PFS in high-risk patients,while 3IC+3CCRT potentially contributed to poor PFS in low-risk individuals,mainly reflected by LRRFS.Conclusions:In LA-NPC patients,2IC+2CCRT was the optimal choice regarding efficacy,toxicity and costeffectiveness;however,2IC+2CCRT and 3IC+3CCRT probably shortened LRRFS in high-and low-risk populations,respectively.
基金Supported by Science and Technology Project of Guangdong Province, China, No. 2010B031600220 and 2008B030303008
文摘AIM:To compare postoperative complications and prognosis of esophageal squamous cell carcinoma patients treated with different routes of reconstruction. METHODS:After obtaining approval from the Medical Ethics Committee of the Sun Yat-Sen University Cancer Center, we retrospectively reviewed data from 306 consecutive patients with histologically diagnosed esophageal squamous cell carcinoma who were treated between 2001 and 2011. All patients underwent radical McKeown-type esophagectomy with at least two-field lymphadenectomy. Regular follow-up was performed in our outpatient department. Postoperative complica-tions and long-term survival were analyzed by treatment modality, baseline patient characteristics, and operative procedure. Data from patients treated via the retrosternal and posterior mediastinal routes were compared. RESULTS:The posterior mediastinal and retrosternal reconstruction routes were employed in 120 and 186 patients, respectively. Pulmonary complications were the most common complications experienced during the postoperative period (46.1% of all patients; 141/306). Compared to the retrosternal route, the posterior mediastinal reconstruction route was associated with a lower incidence of anastomotic stricture (15.8% vs 27.4%, P = 0.018) and less surgical bleeding (242.8 ± 114.2 mL vs 308.2 ± 168.4 mL, P < 0.001). The median survival time was 26.8 mo (range:1.6-116.1 mo). Upon uni/multivariate analysis, a lower preoperative albumin level (P = 0.009) and a more advanced pathological stage (pT; P = 0.006; pN; P < 0.001) were identified as independent factors predicting poor prognosis. The reconstruction route did not influence prognosis (P = 0.477). CONCLUSION:The posterior mediastinal route of reconstruction reduces incidence of postoperative complications but does not affect survival. This route is recommended for resectable esophageal squamous cell carcinoma.
文摘The management of postoperative leaks into the mediastinum after esophagectomy remains a challenge. We describe our clinical management of this complication through endoscopic transluminal drainage. Between 2008 and 2011, 4 patients with esophageal squamous cell carcinoma (ESCC) who underwent McKeown-type esophagectomy with two-field lymphadenectomy experienced complicated anastomotic fistulae in the presence of superior mediastinal sepsis. All 4 patients underwent endoscopic transluminal drainage, and all survived. The mean healing period was 50 days (range, 31 to 58 days), the mean stay in the intensive care unit was 7.3 days (range, 1 to 18 days), and the mean hospital stay was 64.5 days (range, 49 to 70 days). Endoscopically guided transluminal drainage should be considered for ESCC patients with superior mediastinal fistulae after esophagectomy.
文摘AIM: To evaluate whether preoperative mean corpuscular volume (MCV) is a prognostic indicator in patients with resectable esophageal squamous cell carcinoma (ESCC). METHODS: A total of 298 consecutive, prospectively enrolled patients with histologically diagnosed ESCC who underwent surgery with curative intent from 2001 to 2011 were retrospectively evaluated. Patients were excluded if they had previous malignant disease, distant metastasis at the time of primary treatment, a history of neoadjuvant treatment, had undergone nonradical resection, or had died of a non-tumor-associated cause. Survival status was verified in September 2011. Pathological staging was performed based on the 2010 American Joint Committee on Cancer criteria. Preoperative MCV was obtained from blood counts performed routinely within 7 d prior to surgery. Receiver operating characteristic (ROC) curve analysis was used to determine a cutoff for preoperative MCV. RESULTS: The 298 patients consisted of 230 males and 68 females, with a median follow-up of 30.1 mo. ROC analysis showed an optimal cutoff for preoperative MCV of 95.6 fl. Fifty-nine patients (19.8%) had high (> 95.6 fl) and 239 (80.2%) had low (≤ 95.6 fl) preoperative MCV. Preoperative MCV was significantly associated with gender (P=0.003), body mass index (P=0.017), and preoperative red blood cell count (P<0.001). The predicted 1-, 3and 5-year overall survival (OS) rates were 72%, 60% and 52%, respectively. Median OS was significantly longer in patients with low than with high preoperative MCV (27.5 mo vs 19.4 mo, P<0.001). Multivariate analysis showed that advanced pT (P=0.018) and pN (P<0.001) stages, upper thoracic location (P=0.010), lower preoperative albumin concentration (P=0.002), and high preoperative MCV (P=0.001) were negative prognostic factors in patients with ESCC. Preoperative MCV also stratified OS in patients with T3, N1-N3, G2-G3 and stage Ⅲ tumors. CONCLUSION: Preoperative MCV is a prognostic factor in patients with ESCC.
基金National Key R&D Plan Program of China(Grant No.2017YFF0206104)National Key Scien-tific Research Projects of China(Grant No.2015CB921502)+3 种基金National Natural Science Foundation of China(Grant Nos.61574169 and 51871018)Beijing Laboratory of Metallic Materials and Processing for Modern Transportation,the Opening Project of Key Laboratory of Microelectronics Devices&Integrated Technology,Institute of Microelectronics of Chinese Academy of SciencesBeijing Natural Science Foundation(Grant No.Z180014)Beijing Outstanding Young Scientists Projects(Grant No.BJJWZYJH01201910005018)。
文摘Three-dimensional(3 D)topological insulators(TIs)are candidate materials for various electronic and spintronic devices due to their strong spin-orbit coupling and unique surface electronic structure.Rapid,low-cost preparation of large-area TI thin films compatible with conventional semiconductor technology is the key to the practical applications of TIs.Here we show that wafer-sized Bi2Te3 family TI and magnetic TI films with decent quality and well-controlled composition and properties can be prepared on amorphous SiO2/Si substrates by magnetron cosputtering.The SiO2/Si substrates enable us to electrically tune(Bi1-xSbx)2Te3 and Cr-doped(Bi1-xSbx)2 Te3 TI films between p-type and n-type behavior and thus study the phenomena associated with topological surface states,such as the quantum anomalous Hall effect(QAHE).This work significantly facilitates the fabrication of TI-based devices for electronic and spintronic applications.
基金Supported by USDA 2018-67021-27416NSFJS BK20190292.
文摘Background Free-viewpoint video(FVV)is processed video content in which viewers can freely select the viewing position and angle.FVV delivers an improved visual experience and can also help synthesize special effects and virtual reality content.In this paper,a complete FVV system is proposed to interactively control the viewpoints of video relay programs through multimedia terminals such as computers and tablets.Methods The hardware of the FVV generation system is a set of synchronously controlled cameras,and the software generates videos in novel viewpoints from the captured video using view interpolation.The interactive interface is designed to visualize the generated video in novel viewpoints and enable the viewpoint to be changed interactively.Results Experiments show that our system can synthesize plausible videos in intermediate viewpoints with a view range of up to 180°.
基金Supported by the National Key R&D Program of China under Grant No 2016YFA0202102the Fundamental Research Funds for the Central Universities under Grant No 14380078the Scientific Research Foundation of Graduate School of Nanjing University under Grant No 2017CL02
文摘Lens-free holographic microscopy could achieve both improved resolution and field of view(FOV), which has huge potential applications in biomedicine, fluid mechanics and soft matter physics. Unfortunately, due to the limited sensor pixel size, target objects could not be located to a satisfactory level. Recent studies have shown that electromagnetic scattering can be fitted to digital holograms to obtain the 3 D positions of isolated colloidal spheres with nanometer precision and millisecond temporal resolution. Here, we describe a lens-free holographic imaging technique that fits multi-sphere superposition scattering to digital holograms to obtain in situ particle position and model parameters: size and refractive index of colloidal spheres. We show that the proposed method can be utilized to analyze the location and character of colloidal particles under large FOV with high density.
基金supported by the College Students Extracur-ricular Innovation and Entrepreneurship Fund Project of Changzhou University(No.ZMF21020079)the Natural Sci-ence Fund for Colleges and Universities in Jiangsu Province(No.18KJB610001)+4 种基金the Natural Science Foundation of Jiangsu Province(No.BK20180964)the Science and Technology Project of Changzhou City(No.CJ20210119)the Natural Science Foun-dation of China(No.22075032)the National Key Research and Development Program(No.2021YFC3001104)the Natural Sci-ence Foundation of Xinjiang Uygur Autonomous Region(Nos.2020D01A49,2020D01B25 and 2020D01B26).
文摘To improve the selective separation performance of silica nanofibers(SiO_(2)NFs)for cesium ions(Cs+)and overcome the defects of Prussian blue nanoparticles(PB NPs),PB/SiO_(2)-NH_(2)NFs were prepared to remove Cs^(+)from water.Among them,3-aminopropyltriethoxysilane(APTES)underwent an alkylation reaction with SiO_(2),resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO_(2)NFs.Meanwhile,the amino functional groups in APTES combined with Fe3+and then reacted with Fe2+to form PB NPs,which anchored firmly on the aminoated SiO_(2)NFs surface.In our experiment,the maxi-mumadsorption capacity of PB/SiO_(2)-NH_(2)NFs was 111.38 mg/g,which was 31.5mg/g higher than that of SiO_(2)NFs.At the same time,after the fifth cycle,the removal rate of Cs^(+)by PB/SiO_(2)-NH_(2)NFs adsorbent was 75.36%±3.69%.In addition,the adsorption isotherms and adsorption kinetics of PB/SiO_(2)-NH_(2)NFs were combined with the Freundlich model and the quasi-two-stage fitting model,respectively.Further mechanism analysis showed that the bond between PB/SiO_(2)-NH_(2)NFs and Cs^(+)was mainly a synergistic action of ion exchange,electrostatic adsorption and membrane separation.
基金the Fundamental Research Funds for the Central Universities (No.30920021120)Key Laboratory of Biomass Energy and Material,Jiangsu Province (No. JSBEM201912) for financial supporta project funded by the Priority Academic Program development of Jiangsu Higher Education Institution。
文摘An efficient sustainable and scalable strategy for the synthesis of porous cobalt/nitrogen co-doped carbons(Co@NCs) via pyrolysis of aniline-modified ZIFs,has been demonstrated.Aniline can coordinate and absorb on the surface of ZIF(ZIF-CoZn3-PhA),accelerate the precipitation of ZIFs,thus resulting in smaller ZIF particle size.Meanwhile,the aniline on the surface of ZIF-CoZn3-PhA promotes the formation of the protective carbon shell and smaller Co nanoparticles,and increases nitrogen content of the catalyst.Because of these prope rties of Co@NC-PhA-3,the oxidative esterification of 5-hydroxymethylfurfural can be carried out under ambient conditions.According to our experimental and computational results,a synergistic catalytic effect between CoNx sites and Co nanoparticles has been established,in which both Co nanoparticles and CoNx can activate O2 while Co nanoparticles bind and oxidize HMF.Moreover,the formation and release of active oxygen species in CoNx sites are reinfo rced by the electronic interaction between Co nanoparticles and CoNx.
文摘With an urgent demand of energy efficientcoatings for building fenestrations, vanadium dioxide（VO2）-based thermochromic smart coatings have beenwidely investigated due to the reversible phase transition ofVO2 at a critical transition temperature of 68 ℃, which isaccompanied by the modulation of solar irradiation, espe-cially in the near-infrared region. As for commercialapplications in our daily life, there are still some obstaclesfor VO2-based smart coatings, such as the high phasetransition temperature, optical properties （luminous trans-mittance and solar modulation ability）, environmental sta-bility in a long-time period, as well as mass production. Inthis review, recent progress of thermochromic smart coat-ings to solve above obstacles has been surveyed. Mean-while, future development trends have also been given topromote the goal of commercial production of VO2 smartcoatings.
基金supported by the National Key Research and Development Program of China(2017YFA0700202,2021YFB2800701)National Nature Science Foundation of China(61731010,62071217,61971465,62027807,61871212,62025108,62035014)Fundamental Research Funds for the Central Universities,and Research Fund for Jiangsu Key Laboratory of Advanced Techniques for Manipulatinp Electromagnetic Waves.
文摘Spatial light modulators(SLM),capable of dynamically and spatially manipulating electromagnetic waves,have reshaped modern life in projection display and remote sensing.The progress of SLM will expedite next-generation communication and biomedical imaging in the terahertz(THz)range.However,most current THz SLMs are adapted from optical alternatives that still need improvement in terms of uniformity,speed,and bandwidth.Here,we designed,fabricated,and characterized an 8×8THz SLM based on tunable liquid crystal metamaterial absorbers for THz single-pixel compressive imaging.We demonstrated dual-color compressive sensing(CS)imaging for dispersive objects utilizing the large frequency shift controlled by an external electric field.We developed auto-calibrated compressive sensing(ACS)algorithm to mitigate the impact of the spatially nonuniform THz incident beam and pixel modulation,which significantly improves the fidelity of reconstructed images.Furthermore,the complementary modulation at two absorption frequencies enables Hadamard masks with negative element values to be realized by frequency-switching,thereby halving the imaging time.The demonstrated imaging system paves a new route for THz single-pixel multispectral imaging with high reliability and low cost.
基金This work was supported by the National Natural Science Foundation of China （Grant Nos. 61371166, and 61422107） and the Natural Science Foundation of Jiangsu Province, China （BK20130583）.
文摘The prior knowledge is the significant supple- ment to image-based 3D modeling algorithms for refining the fragile consistency-based stereo. In this paper, we review the image-based 3D modeling problem according to prior cate- gories, i.e., classical priors and specific priors. The classical priors including smoothness, silhouette and illumination are well studied for improving the accuracy and robustness of the 3D reconstruction. In recent years, various specific priors which take advantage of Manhattan rule, geometry template and trained category features have been proposed to enhance the modeling performance. The advantages and limitations of both kinds of priors are discussed and evaluated in the paper. Finally, we discuss the trend and challenges of the prior studies in the future.
基金National Natural Science Foundation of China(62071219,62025108)Natural Science Foundation of Jiangsu Province(BK20190292)。
文摘Micro-endoscopes are widely used for detecting and visualizing hard-to-reach areas of the human body and for in vivo observation of animals.A micro-endoscope that can realize 3D imaging at the camera framerate could benefit various clinical and biological applications.In this work,we report the development of a compact light-field micro-endoscope(LFME)that can obtain snapshot 3D fluorescence imaging,by jointly using a single-mode fiber bundle and a small-size light-field configuration.To demonstrate the real imaging performance of our method,we put a resolution chart in different z positions and capture the z-stack images successively for reconstruction,achieving 333-μm-diameter field of view,24μm optimal depth of field,and up to 3.91μm spatial resolution near the focal plane.We also test our method on a human skin tissue section and He La cells.Our LFME prototype provides epi-fluorescence imaging ability with a relatively small(2-mm-diameter)imaging probe,making it suitable for in vivo detection of brain activity and gastrointestinal diseases of animals.
基金the support by the National Natural Science Foundation of China(11774365)。
文摘Oxygen-containing rare-earth metal hydride YH_xO_y,is a newly found photochromic material showing fast photoresponse.While its preparation method,optical properties and structural features have been studied extensively,the photochromic mechanism in YH_xO_yremains unknown Here,using excited-state molecular dynamics simulation based on the recently developed real-time time-dependent density functional theory(RT-TDDFT)method,we study the photochemical reactions in YH_xO_y.We find that under photoexcitation,dihydrogen defects are formed within 100 fs.The dihydrogen defect behaves as a shallow donor and renders the material strongly n-type doped,which could be responsible for the photochromic effect observed in YH_xO_y.We also find that oxygen concentration affects the metastability of the dihydrogen species,meaning that the energy barrier for the dihydrogen to dissociate is related to the oxygen concentration The highest barrier of 0.28 eV is found in our model with O/Y=1:8.If the oxygen concentration is too low,the dihydrogen will quickly dissociate when the excitation is turned off.If the oxygen concentration is too high,the dihydrogen dissociates even when the excitation is still on.
基金the MOE AcRF Tier 1 grant M4011528.The XRD and FEG-TEM characterisations were performed at Facility for Analysis,Characterisation,Testing and Simulation(FACTS)Labthe FEG-SEM/FIB characterisations were carried out at Microelectronics Reliability and Characterisation(MRC)Lab.
文摘The catalysis of Au thin film could be improved by fabrication of array structures in large area.In this work,nanoimprint lithography has been developed tofabricate flexible Au micro-array(MA)electrodes with~100%coverage.Advanced electron microscopy characterisations have directly visualised the atomic-scale three-dimensional(3D)nanostructures with a maximum depth of 6 atomic layers.In-situ observation unveils the crystal growth in the form of twinning.High double layer capacitance brings about large number of active sites on the Au thin film and has a logarithmic relationship with mesh grade.Electrochemistry testing shows that the Au MAs perform much better ethanol oxidation reaction than the planar sample;MAs with higher mesh grade have a greater active site utilisation ratio(ASUR),which is important to build electrochemical double layer for efficient charge transfer.Further improvement on ASUR is expected for greater electrocatalytic performance and potential application in direct ethanol fuel cell.
基金Acknowledgements This study was financially supported by the National Natural Science Foundation of China （Grant Nos. 51032008, 51272271 and 51172265） and the National Key Basic Research Program （NKBRP, 2009CB939904）.
文摘Switchable mirrors based on magnesium-nickel alloy thin films capped with catalytic Pd-Ni alloy thin films were prepared by a DC magnetron sputtering method. Their composition, structure and surface morphology were studied by XPS, XRD and AFM. Herein, the optical switching properties and durability of the switchable mirrors were investigated by varying the Ni content in the Pd-Ni alloys. Comparing pure Pd catalyst with Pd-Ni top-capped switchable mirrors, the latter show better hydrogenation and dehydrogenation kinetics, and the speed of hydrogen desorption is obviously improved with increasing Ni content in the Pd-Ni alloy. The Pd-Ni capped switchable mirrors also have better optical switching durability. The catalytic Pd layer with the addition of Ni does not influence the transmittance （hydride state） and reflectance （metallic state） of the switchable mirrors. In addition, replacing Pd with Pd-Ni alloy decreases the cost of the switchable mirrors： employing nickel in the alloy Pd89.2Ni10.8 can save about 11% use of Pd. Therefore, the Pd-Ni alloy can provide a cheaper catalytic thin film, and it is expected to have applications in energy-saving windows, hydrogen sensors and hydrogen storage materials.
基金Project supported by the National Natural Science Foundation of China （Nos. 61627804, 61371166, 61422107, 61571215, and 61671236） and the Natural Science Foundation of Jiangsu Province, China （Nos. BK20140610 and BK20160634）
文摘Compared with conventional cameras, spectral imagers provide many more features in the spectral do- main. They have been used in various fields such as material identification, remote sensing, precision agriculture, and surveillance. Traditional imaging spectrometers use generally scanning systems. They cannot meet the demands of dynamic scenarios. This limits the practical applications for spectral imaging. Recently, with the rapid development in computational photography theory and semiconductor techniques, spectral video acquisition has become feasible. This paper aims to offer a review of the state-of-the-art spectral imaging technologies, especially those capable of capturing spectral videos. Finally, we evaluate the performances of the existing spectral acquisition systems and discuss the trends for future work.
