Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the visi...Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the vision system,an image mosaic technique must be used.In this paper,a method for constructing an image mosaic with non-overlapping areas with enhanced efficiency is proposed.First,an image mosaic model for the part is created using a geometric model of the measurement system installed on a X-Y-Z precision stages with high repeatability,and a path for image acquisition is established.Second,images are captured along the same path for a specified calibration plate,and an entire image is formed based on the given model.The measurement results obtained from the specified calibration plate are utilized to identify mosaic errors and apply compensation for the part requiring measurement.Experimental results show that the maximum error is less than 4μm for a camera with pixel equivalent 2.46μm,thereby demonstrating the accuracy of the proposed method.This image mosaic technique with non-overlapping regions can simplify image acquisition and reduce the workload involved in constructing an image mosaic.展开更多
Accurate histopathology classification is a crucial factor in the diagnosis and treatment of Cholangiocarcinoma(CCA).Hyperspectral images(HSI)provide rich spectral information than ordinary RGB images,making them more...Accurate histopathology classification is a crucial factor in the diagnosis and treatment of Cholangiocarcinoma(CCA).Hyperspectral images(HSI)provide rich spectral information than ordinary RGB images,making them more useful for medical diagnosis.The Convolutional Neural Network(CNN)is commonly employed in hyperspectral image classification due to its remarkable capacity for feature extraction and image classification.However,many existing CNN-based HSI classification methods tend to ignore the importance of image spatial context information and the interdependence between spectral channels,leading to unsatisfied classification performance.Thus,to address these issues,this paper proposes a Spatial-Spectral Joint Network(SSJN)model for hyperspectral image classification that utilizes spatial self-attention and spectral feature extraction.The SSJN model is derived from the ResNet18 network and implemented with the non-local and Coordinate Attention(CA)modules,which extract long-range dependencies on image space and enhance spatial features through the Branch Attention(BA)module to emphasize the region of interest.Furthermore,the SSJN model employs Conv-LSTM modules to extract long-range depen-dencies in the image spectral domain.This addresses the gradient disappearance/explosion phenom-ena and enhances the model classification accuracy.The experimental results show that the pro-posed SSJN model is more efficient in leveraging the spatial and spectral information of hyperspec-tral images on multidimensional microspectral datasets of CCA,leading to higher classification accuracy,and may have useful references for medical diagnosis of CCA.展开更多
Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for ...Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction.展开更多
Optical imaging systems have greatly extended human visual capabilities,enabling the observation and understanding of diverse phenomena.Imaging technologies span a broad spectrum of wavelengths from x-ray to radio fre...Optical imaging systems have greatly extended human visual capabilities,enabling the observation and understanding of diverse phenomena.Imaging technologies span a broad spectrum of wavelengths from x-ray to radio frequencies and impact research activities and our daily lives.Traditional glass lenses are fabricated through a series of complex processes,while polymers offer versatility and ease of production.However,modern applications often require complex lens assemblies,driving the need for miniaturization and advanced designs with micro-and nanoscale features to surpass the capabilities of traditional fabrication methods.Three-dimensional(3D)printing,or additive manufacturing,presents a solution to these challenges with benefits of rapid prototyping,customized geometries,and efficient production,particularly suited for miniaturized optical imaging devices.Various 3D printing methods have demonstrated advantages over traditional counterparts,yet challenges remain in achieving nanoscale resolutions.Two-photon polymerization lithography(TPL),a nanoscale 3D printing technique,enables the fabrication of intricate structures beyond the optical diffraction limit via the nonlinear process of two-photon absorption within liquid resin.It offers unprecedented abilities,e.g.alignment-free fabrication,micro-and nanoscale capabilities,and rapid prototyping of almost arbitrary complex 3D nanostructures.In this review,we emphasize the importance of the criteria for optical performance evaluation of imaging devices,discuss material properties relevant to TPL,fabrication techniques,and highlight the application of TPL in optical imaging.As the first panoramic review on this topic,it will equip researchers with foundational knowledge and recent advancements of TPL for imaging optics,promoting a deeper understanding of the field.By leveraging on its high-resolution capability,extensive material range,and true 3D processing,alongside advances in materials,fabrication,and design,we envisage disruptive solutions to current challenges and a promising incorporation of TPL in future optical imaging applications.展开更多
An intelligent lithology identification method is proposed based on deep learning of the rock microscopic images.Based on the characteristics of rock images in the dataset,we used Xception,MobileNet_v2,Inception_ResNe...An intelligent lithology identification method is proposed based on deep learning of the rock microscopic images.Based on the characteristics of rock images in the dataset,we used Xception,MobileNet_v2,Inception_ResNet_v2,Inception_v3,Densenet121,ResNet101_v2,and ResNet-101 to develop microscopic image classification models,and then the network structures of seven different convolutional neural networks(CNNs)were compared.It shows that the multi-layer representation of rock features can be represented through convolution structures,thus better feature robustness can be achieved.For the loss function,cross-entropy is used to back propagate the weight parameters layer by layer,and the accuracy of the network is improved by frequent iterative training.We expanded a self-built dataset by using transfer learning and data augmentation.Next,accuracy(acc)and frames per second(fps)were used as the evaluation indexes to assess the accuracy and speed of model identification.The results show that the Xception-based model has the optimum performance,with an accuracy of 97.66%in the training dataset and 98.65%in the testing dataset.Furthermore,the fps of the model is 50.76,and the model is feasible to deploy under different hardware conditions and meets the requirements of rapid lithology identification.This proposed method is proved to be robust and versatile in generalization performance,and it is suitable for both geologists and engineers to identify lithology quickly.展开更多
Leukaemia is a type of blood cancer that is caused by undeveloped White Blood Cells(WBC),and it is also called a blast blood cell.In the marrow of human bones,leukaemia is developed and is responsible for blood cell g...Leukaemia is a type of blood cancer that is caused by undeveloped White Blood Cells(WBC),and it is also called a blast blood cell.In the marrow of human bones,leukaemia is developed and is responsible for blood cell generation with leukocytes and WBC,and if any cell gets blasted,then it may become a cause of death.Therefore,the diagnosis of leukaemia in its early stages helps greatly in the treatment along with saving human lives.Subsequently,in terms of detection,image segmentation techniques play a vital role,and they turn out to be the important image processing steps for the extraction of feature patterns from the Acute Lymphoblastic Leukaemia(ALL)type of blood cancer.Moreover,the image segmentation technique focuses on the division of cells by segmenting a microscopic image into background and cancer blood cell nucleus,which is well-known as the Region Of Interest(ROI).As a result,in this article,we attempt to build a segmentation technique capable of solving blood cell nucleus segmentation issues using four distinct scenarios,including K-means,FCM(Fuzzy Cmeans),K-means with FFA(Firefly Algorithm),and FCM with FFA.Also,we determine the most effective method of blood cell nucleus segmentation,which we subsequently use for the Leukaemia classification model.Finally,using the Convolution Neural Network(CNN)as a classifier,we developed a leukaemia cancer classification model from the microscopic images.The proposed system’s classification accuracy is tested using the CNN to test the model on the ALL-IDB dataset and equate it to the current state of the art.In terms of experimental analysis,we observed that the accuracy of the model is near to 99%,and it is far better than other existing models that are designed to segment and classify the types of leukaemia cancer in terms of ALL.展开更多
Pigmented spot is an important branch in the science of skin. But when processing those images, the microscopical focusing problem arises. It affects the image recognition later. In order to find the best method to so...Pigmented spot is an important branch in the science of skin. But when processing those images, the microscopical focusing problem arises. It affects the image recognition later. In order to find the best method to solve it, comparison and analysis are given to various existing methods of image fusion in this paper . The conclusion is wavelet transform based on pixel-level.展开更多
In image acquisition process, the quality of microscopic images will be degraded by electrical noise, quantizing noise, light illumination etc. Hence, image preprocessing is necessary and important to improve the qual...In image acquisition process, the quality of microscopic images will be degraded by electrical noise, quantizing noise, light illumination etc. Hence, image preprocessing is necessary and important to improve the quality. The background noise and pulse noise are two common types of noise existing in microscopic images. In this paper, a gradient-based anisotropic filtering algorithm was proposed, which can filter out the background noise while preserve object boundary effectively. The filtering performance was evaluated by comparing that with some other filtering algorithms.展开更多
Cracking behaviors of rocks significantly affect the safety and stability of the explorations of underground space and deep resources.To understand deeply the microscopic cracking process and mechanical property of ro...Cracking behaviors of rocks significantly affect the safety and stability of the explorations of underground space and deep resources.To understand deeply the microscopic cracking process and mechanical property of rocks,X-ray micro-computed tomography(X-μCT)is applied to capture the rock microstructures.The digital color difference UNet(DCD-UNet)-based deep learning algorithm with 3D reconstruction is proposed to reconstruct the multiphase heterogeneity microstructure models of rocks.The microscopic cracking and mechanical properties are studied based on the proposed microstructure-based peridynamic model.Results show that the DCD-UNet algorithm is more effective to recognize and to represent the microscopic multiphase heterogeneity of rocks.As damage characteristic index of multiphase rocks increases,transgranular cracks in the same grain phase,transgranular and intergranular cracks of pore-grain phase,intergranular and secondary transgranular cracks and transgranular crack between different grains propagate.The ultimate microscopic failure modes of rocks are mainly controlled by the transgranular cracks-based T1-shear,T3-shear,T1-tension,T2-tension and T3-tension failures,and the intergranular cracks-based T1-tension,T1-shear and T3-shear failures under uniaxial compression.展开更多
The volumetric imaging of two-photon microscopy expands the focal depth and improves the throughput,which has unparalleled superiority for three-dimension samples,especially in neuroscience.However,emerging in volumet...The volumetric imaging of two-photon microscopy expands the focal depth and improves the throughput,which has unparalleled superiority for three-dimension samples,especially in neuroscience.However,emerging in volumetric imaging is still largely customized,which limits the integration with commercial two-photon systems.Here,we analyzed the key parameters that modulate the focal depth and lateral resolution of polarized annular imaging and proposed a volumetric imaging module that can be directly integrated into commercial two-photon systems using conventional optical elements.This design incorporates the beam diameter adjustment settings of commercial two-photon systems,allowing flexibility to adjust the depth of focus while maintaining the same lateral resolution.Further,the depth range and lateral resolution of the design were verified,and the imaging throughput was demonstrated by an increase in the number of imaging neurons in the awake mouse cerebral cortex.展开更多
Screening and diagnosing of abnormal Leukocytes are crucial for the diagnosis of immune diseases and Acute Lymphoblastic Leukemia(ALL).As the deterioration of abnormal leukocytes is mainly due to the changes in the ch...Screening and diagnosing of abnormal Leukocytes are crucial for the diagnosis of immune diseases and Acute Lymphoblastic Leukemia(ALL).As the deterioration of abnormal leukocytes is mainly due to the changes in the chromatin distribution,which signicantly affects the absorption and reflection of light,the spectral feature is proved to be important for leukocytes classication and identication.This paper proposes an accurate identication method for healthy and abnormal leukocytes based on microscopic hyperspectral imaging(HSI)technology which combines the spectral information.The segmentation of nucleus and cytoplasm is obtained by the morphological watershed algorithm.Then,the spectral features are extracted and combined with the spatial features.Based on this,the support vector machine(SVM)is applied for classication ofve types of leukocytes and abnormal leukocytes.Compared with different classication methods,the proposed method utilizes spectral features which highlight the differences between healthy leukocytes and abnormal leukocytes,improving the accuracy in the classication and identication of leukocytes.This paper only selects one subtype of ALL for test,and the proposed method can be applied for detection of other leukemia in the future.展开更多
Apoptosis is very important for the maintenance of cellular homeostasis and is closely related to the occurrence and treatment of many diseases.Mitochondria in cells play a crucial role in programmed cell death and re...Apoptosis is very important for the maintenance of cellular homeostasis and is closely related to the occurrence and treatment of many diseases.Mitochondria in cells play a crucial role in programmed cell death and redox processes.Nicotinamide adenine dinucleotide(NAD(P)H)is the primary producer of energy in mitochondria,changing NAD(P)H can directly reflect the physiological state of mitochondria.Therefore,NAD(P)H can be used to evaluate metabolic response.In this paper,we propose a noninvasive detection method that uses two-photon fluorescence lifetime imaging microscopy(TP-FLIM)to characterize apoptosis by observing the binding kinetics of cellular endogenous NAD(P)H.The result shows that the average fluorescence lifetime of NAD(P)H and the fluorescence lifetime of protein-bound NAD(P)H will be affected by the changing pH,serum content,and oxygen concentration in the cell culture environment,and by the treatment with reagents such as H2O2 and paclitaxel.Taxol(PTX).This noninvasive detection method realized the dynamic detection of cellular endogenous substances and the assessment of apoptosis.展开更多
In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output...In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW.展开更多
Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are ...Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are lacking.Emerging in vivo imaging and labeling methods offer great potential for observing dynamic neural processes in the central nervous system in conditions of health and disease.This review first discusses in vivo imaging of the mouse spinal cord with a focus on the latest imaging techniques,and then analyzes the dynamic biological response of spinal cord sensory and motor neurons to SCI.We then summarize and compare the techniques behind these studies and clarify the advantages of in vivo imaging compared with traditional neuroscience examinations.Finally,we identify the challenges and possible solutions for spinal cord neuron imaging.展开更多
The wavelength dependence of photoelectron angular distributions (PADs) of two-photon detachment of Cu^- has been directly studied by using the photoelectron map imaging. Results show that for the laser field intens...The wavelength dependence of photoelectron angular distributions (PADs) of two-photon detachment of Cu^- has been directly studied by using the photoelectron map imaging. Results show that for the laser field intensity of 6.0×10^10W/cm^2, PADs exhibit dramatic change with the external field wavelength. Comparison between the experimental observation and the lowest-order perturbation theory prediction indicates that the pattern of PADs can be explained by the interference of the s and d partial waves in the final state. Relative contri- butions of s and d partial waves in the two-photon detachment at different laser wavelengths are obtained.展开更多
Background:Pathological scars are a disorder that can lead to various cosmetic,psychological,and functional problems,and no effective assessment methods are currently available.Assessment and treatment of pathological...Background:Pathological scars are a disorder that can lead to various cosmetic,psychological,and functional problems,and no effective assessment methods are currently available.Assessment and treatment of pathological scars are based on cutaneous manifestations.A two-photon microscope(TPM)with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo.This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients.Methods:Fifteen patients with pathological scars and three healthy controls were recruited.Imaging was performed using a portable handheld TPM.Five indexes were extracted from two dimensional(2D)and three dimensional(3D)perspectives,including collagen depth,dermo-epidermal junction(DEJ)contour ratio,thickness,orientation,and occupation(proportion of collagen fibers in the field of view)of collagen.Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images.We assessed index differences between scar and normal skin and changes before and after treatment.Results:Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers.Five indexes were employed to distinguish between normal skin and scar tissue.Statistically significant differences were found in average depth(t=9.917,P<0.001),thickness(t=4.037,P<0.001),occupation(t=2.169,P<0.050),orientation of collagen(t=3.669,P<0.001),and the DEJ contour ratio(t=5.105,P<0.001).Conclusions:Use of portable handheld TPM can distinguish collagen from skin tissues;thus,it is more suitable for scar imaging than reflectance confocal microscopy.Thus,a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.展开更多
Waterflooding experiments were performed using Micro-CT on four cores of different pore structures from Donghe sandstone reservoirs in the Tarim Basin. The water, oil and grains were accurately separated by the advanc...Waterflooding experiments were performed using Micro-CT on four cores of different pore structures from Donghe sandstone reservoirs in the Tarim Basin. The water, oil and grains were accurately separated by the advanced image processing technology, the pore network model was established, and parameters such as the number of throats and the throat size distribution were calculated to characterize the microscopic heterogeneity of pore structure, the flow of oil phase during displacement, and the morphology and distribution of remaining oil after displacement. The cores with the same macroscopic porosity-permeability have great differences in microscopic heterogeneity of pore structure. Both macro porosity-permeability and micro heterogeneity of pore structure have an influence on the migration of oil phase and the morphology and distribution of remaining oil. When the heterogeneity is strong, the water phase will preferentially flow through the dominant paths and the remaining oil clusters will be formed in the small pores. The more the number of oil clusters(droplets) formed during displacement process, the smaller the average volume of cluster is, and the remaining oil is dominated by the cluster continuous phase with high saturation. The weaker the heterogeneity, the higher the pore sweep efficiency is, and the remaining oil clusters are mainly trapped in the form of non-continuous phase. The distribution and morphology of micro remaining oil are related to the absolute permeability, capillary number and micro-heterogeneity. So, the identification plate of microscopic residual oil continuity distribution established on this basis can describe the relationship between these three factors and distribution of remaining oil and identify the continuity of the remaining oil distribution accurately.展开更多
A leukocyte image fast scanning method based on max min distance clustering is proposed.Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood,there will not be any leukocyte i...A leukocyte image fast scanning method based on max min distance clustering is proposed.Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood,there will not be any leukocyte in lager quantity of the captured images if we directly scan the blood smear along an ordinary zigzag scanning routine with high power(100^(x))objective.Due to the larger field of view of low power(10^(x))objective,the captured low power blood smear images can be used to locate leukocytes.All of the located positions make up a specific routine,if we scan the blood smear along this routine with high power objective,there will be definitely leukocytes in almost all of the captured images.Considering the number of captured images is still large and some leukocytes may be redundantly captured twice or more,a leukocyte clustering method based on max-min distance clustering is developed to reduce the total number of captured images as well as the number of redundantly captured leukocytes.This method can improve the scanning eficiency obviously.The experimental results show that the proposed method can shorten scanning time from 8.0-14.0min to 2.54.0 min while extracting 110 nonredundant individual high power leukocyte images.展开更多
基金supported by the Liaoning Revitalization Talents Program(Grant No.XLYC2002020)the Major Project of Basic Scientific Research of Chinese Ministry(Grant No.JCYK2016205A003).
文摘Microscopic vision has been widely applied in precision assembly.To achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the vision system,an image mosaic technique must be used.In this paper,a method for constructing an image mosaic with non-overlapping areas with enhanced efficiency is proposed.First,an image mosaic model for the part is created using a geometric model of the measurement system installed on a X-Y-Z precision stages with high repeatability,and a path for image acquisition is established.Second,images are captured along the same path for a specified calibration plate,and an entire image is formed based on the given model.The measurement results obtained from the specified calibration plate are utilized to identify mosaic errors and apply compensation for the part requiring measurement.Experimental results show that the maximum error is less than 4μm for a camera with pixel equivalent 2.46μm,thereby demonstrating the accuracy of the proposed method.This image mosaic technique with non-overlapping regions can simplify image acquisition and reduce the workload involved in constructing an image mosaic.
基金supported by National Natural Science Foundation of China(No.62101040).
文摘Accurate histopathology classification is a crucial factor in the diagnosis and treatment of Cholangiocarcinoma(CCA).Hyperspectral images(HSI)provide rich spectral information than ordinary RGB images,making them more useful for medical diagnosis.The Convolutional Neural Network(CNN)is commonly employed in hyperspectral image classification due to its remarkable capacity for feature extraction and image classification.However,many existing CNN-based HSI classification methods tend to ignore the importance of image spatial context information and the interdependence between spectral channels,leading to unsatisfied classification performance.Thus,to address these issues,this paper proposes a Spatial-Spectral Joint Network(SSJN)model for hyperspectral image classification that utilizes spatial self-attention and spectral feature extraction.The SSJN model is derived from the ResNet18 network and implemented with the non-local and Coordinate Attention(CA)modules,which extract long-range dependencies on image space and enhance spatial features through the Branch Attention(BA)module to emphasize the region of interest.Furthermore,the SSJN model employs Conv-LSTM modules to extract long-range depen-dencies in the image spectral domain.This addresses the gradient disappearance/explosion phenom-ena and enhances the model classification accuracy.The experimental results show that the pro-posed SSJN model is more efficient in leveraging the spatial and spectral information of hyperspec-tral images on multidimensional microspectral datasets of CCA,leading to higher classification accuracy,and may have useful references for medical diagnosis of CCA.
基金supported by the National Natural Science Foundation of China,No.31970906(to WLei)the Natural Science Foundation of Guangdong Province,No.2020A1515011079(to WLei)+4 种基金Key Technologies R&D Program of Guangdong Province,No.2018B030332001(to GC)Science and Technology Projects of Guangzhou,No.202206060002(to GC)the Youth Science Program of the National Natural Science Foundation of China,No.32100793(to ZX)the Pearl River Innovation and Entrepreneurship Team,No.2021ZT09 Y552Yi-Liang Liu Endowment Fund from Jinan University Education Development Foundation。
文摘Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction.
基金support from the National Research Foundation (NRF) Singapore, under its Competitive Research Programme Award NRF-CRP20-20170004 and NRF Investigatorship Award NRF-NRFI06-20200005MTC Programmatic Grant M21J9b0085, as well as the Lite-On Project RS-INDUS-00090+5 种基金support from Australian Research Council (DE220101085, DP220102152)grants from German Research Foundation (SCHM2655/15-1, SCHM2655/21-1)Lee-Lucas Chair in Physics and funding by the Australian Research Council DP220102152financial support from the National Natural Science Foundation of China (Grant No. 62275078)Natural Science Foundation of Hunan Province of China (Grant No. 2022JJ20020)Shenzhen Science and Technology Program (Grant No. JCYJ20220530160405013)
文摘Optical imaging systems have greatly extended human visual capabilities,enabling the observation and understanding of diverse phenomena.Imaging technologies span a broad spectrum of wavelengths from x-ray to radio frequencies and impact research activities and our daily lives.Traditional glass lenses are fabricated through a series of complex processes,while polymers offer versatility and ease of production.However,modern applications often require complex lens assemblies,driving the need for miniaturization and advanced designs with micro-and nanoscale features to surpass the capabilities of traditional fabrication methods.Three-dimensional(3D)printing,or additive manufacturing,presents a solution to these challenges with benefits of rapid prototyping,customized geometries,and efficient production,particularly suited for miniaturized optical imaging devices.Various 3D printing methods have demonstrated advantages over traditional counterparts,yet challenges remain in achieving nanoscale resolutions.Two-photon polymerization lithography(TPL),a nanoscale 3D printing technique,enables the fabrication of intricate structures beyond the optical diffraction limit via the nonlinear process of two-photon absorption within liquid resin.It offers unprecedented abilities,e.g.alignment-free fabrication,micro-and nanoscale capabilities,and rapid prototyping of almost arbitrary complex 3D nanostructures.In this review,we emphasize the importance of the criteria for optical performance evaluation of imaging devices,discuss material properties relevant to TPL,fabrication techniques,and highlight the application of TPL in optical imaging.As the first panoramic review on this topic,it will equip researchers with foundational knowledge and recent advancements of TPL for imaging optics,promoting a deeper understanding of the field.By leveraging on its high-resolution capability,extensive material range,and true 3D processing,alongside advances in materials,fabrication,and design,we envisage disruptive solutions to current challenges and a promising incorporation of TPL in future optical imaging applications.
基金support from the National Natural Science Foundation of China(Grant Nos.52022053 and 52009073)the Natural Science Foundation of Shandong Province(Grant No.ZR201910270116).
文摘An intelligent lithology identification method is proposed based on deep learning of the rock microscopic images.Based on the characteristics of rock images in the dataset,we used Xception,MobileNet_v2,Inception_ResNet_v2,Inception_v3,Densenet121,ResNet101_v2,and ResNet-101 to develop microscopic image classification models,and then the network structures of seven different convolutional neural networks(CNNs)were compared.It shows that the multi-layer representation of rock features can be represented through convolution structures,thus better feature robustness can be achieved.For the loss function,cross-entropy is used to back propagate the weight parameters layer by layer,and the accuracy of the network is improved by frequent iterative training.We expanded a self-built dataset by using transfer learning and data augmentation.Next,accuracy(acc)and frames per second(fps)were used as the evaluation indexes to assess the accuracy and speed of model identification.The results show that the Xception-based model has the optimum performance,with an accuracy of 97.66%in the training dataset and 98.65%in the testing dataset.Furthermore,the fps of the model is 50.76,and the model is feasible to deploy under different hardware conditions and meets the requirements of rapid lithology identification.This proposed method is proved to be robust and versatile in generalization performance,and it is suitable for both geologists and engineers to identify lithology quickly.
基金We deeply acknowledge Taif University for supporting this study through Taif University Researchers Supporting Project number(TURSP-2020/115),Taif University,Taif,Saudi Arabia.
文摘Leukaemia is a type of blood cancer that is caused by undeveloped White Blood Cells(WBC),and it is also called a blast blood cell.In the marrow of human bones,leukaemia is developed and is responsible for blood cell generation with leukocytes and WBC,and if any cell gets blasted,then it may become a cause of death.Therefore,the diagnosis of leukaemia in its early stages helps greatly in the treatment along with saving human lives.Subsequently,in terms of detection,image segmentation techniques play a vital role,and they turn out to be the important image processing steps for the extraction of feature patterns from the Acute Lymphoblastic Leukaemia(ALL)type of blood cancer.Moreover,the image segmentation technique focuses on the division of cells by segmenting a microscopic image into background and cancer blood cell nucleus,which is well-known as the Region Of Interest(ROI).As a result,in this article,we attempt to build a segmentation technique capable of solving blood cell nucleus segmentation issues using four distinct scenarios,including K-means,FCM(Fuzzy Cmeans),K-means with FFA(Firefly Algorithm),and FCM with FFA.Also,we determine the most effective method of blood cell nucleus segmentation,which we subsequently use for the Leukaemia classification model.Finally,using the Convolution Neural Network(CNN)as a classifier,we developed a leukaemia cancer classification model from the microscopic images.The proposed system’s classification accuracy is tested using the CNN to test the model on the ALL-IDB dataset and equate it to the current state of the art.In terms of experimental analysis,we observed that the accuracy of the model is near to 99%,and it is far better than other existing models that are designed to segment and classify the types of leukaemia cancer in terms of ALL.
文摘Pigmented spot is an important branch in the science of skin. But when processing those images, the microscopical focusing problem arises. It affects the image recognition later. In order to find the best method to solve it, comparison and analysis are given to various existing methods of image fusion in this paper . The conclusion is wavelet transform based on pixel-level.
文摘In image acquisition process, the quality of microscopic images will be degraded by electrical noise, quantizing noise, light illumination etc. Hence, image preprocessing is necessary and important to improve the quality. The background noise and pulse noise are two common types of noise existing in microscopic images. In this paper, a gradient-based anisotropic filtering algorithm was proposed, which can filter out the background noise while preserve object boundary effectively. The filtering performance was evaluated by comparing that with some other filtering algorithms.
基金supported by the National Natural Science Foundation of China(Nos.42207193,52027814,and 51839009)the Natural Science Foundation of Hubei Province(No.2022CFB609)+1 种基金the National Center for International Research on Deep Earth Drilling and Resource Development(No.DEDRD-2022-07)the Fundamental Research Funds for the Central Universities(No.2042021kf0058)。
文摘Cracking behaviors of rocks significantly affect the safety and stability of the explorations of underground space and deep resources.To understand deeply the microscopic cracking process and mechanical property of rocks,X-ray micro-computed tomography(X-μCT)is applied to capture the rock microstructures.The digital color difference UNet(DCD-UNet)-based deep learning algorithm with 3D reconstruction is proposed to reconstruct the multiphase heterogeneity microstructure models of rocks.The microscopic cracking and mechanical properties are studied based on the proposed microstructure-based peridynamic model.Results show that the DCD-UNet algorithm is more effective to recognize and to represent the microscopic multiphase heterogeneity of rocks.As damage characteristic index of multiphase rocks increases,transgranular cracks in the same grain phase,transgranular and intergranular cracks of pore-grain phase,intergranular and secondary transgranular cracks and transgranular crack between different grains propagate.The ultimate microscopic failure modes of rocks are mainly controlled by the transgranular cracks-based T1-shear,T3-shear,T1-tension,T2-tension and T3-tension failures,and the intergranular cracks-based T1-tension,T1-shear and T3-shear failures under uniaxial compression.
基金supported by STI2030-Major Projects (2021ZD0201001 to H.G.)the National Natural Science Foundation of China (61890951 and 31871027 to W.Z.)+2 种基金Fundamental Research Funds for the Central Universities (HUST:2019KFYXMBZ011,2019KFYXMBZ039,2018KFYXMPT018,2019KFYXMBZ009 to H.G.)CAMS Innovation Fund for Medical Sciences (CIFMS,2019-I2M-5-014 to H.G.)the director fund of the WNLO.
文摘The volumetric imaging of two-photon microscopy expands the focal depth and improves the throughput,which has unparalleled superiority for three-dimension samples,especially in neuroscience.However,emerging in volumetric imaging is still largely customized,which limits the integration with commercial two-photon systems.Here,we analyzed the key parameters that modulate the focal depth and lateral resolution of polarized annular imaging and proposed a volumetric imaging module that can be directly integrated into commercial two-photon systems using conventional optical elements.This design incorporates the beam diameter adjustment settings of commercial two-photon systems,allowing flexibility to adjust the depth of focus while maintaining the same lateral resolution.Further,the depth range and lateral resolution of the design were verified,and the imaging throughput was demonstrated by an increase in the number of imaging neurons in the awake mouse cerebral cortex.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.61975056 and 61901173)the Shanghai Natural Science Foundation(Grant No.19ZR1416000)the Science and Technology Commission of Shanghai Municipality(Grant Nos.14DZ2260800 and 18511102500).
文摘Screening and diagnosing of abnormal Leukocytes are crucial for the diagnosis of immune diseases and Acute Lymphoblastic Leukemia(ALL).As the deterioration of abnormal leukocytes is mainly due to the changes in the chromatin distribution,which signicantly affects the absorption and reflection of light,the spectral feature is proved to be important for leukocytes classication and identication.This paper proposes an accurate identication method for healthy and abnormal leukocytes based on microscopic hyperspectral imaging(HSI)technology which combines the spectral information.The segmentation of nucleus and cytoplasm is obtained by the morphological watershed algorithm.Then,the spectral features are extracted and combined with the spatial features.Based on this,the support vector machine(SVM)is applied for classication ofve types of leukocytes and abnormal leukocytes.Compared with different classication methods,the proposed method utilizes spectral features which highlight the differences between healthy leukocytes and abnormal leukocytes,improving the accuracy in the classication and identication of leukocytes.This paper only selects one subtype of ALL for test,and the proposed method can be applied for detection of other leukemia in the future.
基金supported in part by the National Key R&D Program of China(2017YFA0700402)National Natural Science Foundation of China(61961136005/61935012/62175163/61835009)+1 种基金Shenzhen Key projects(JCYJ20200109105404067)Shenzhen International Cooperation Project(GJHZ 20190822095420249).
文摘Apoptosis is very important for the maintenance of cellular homeostasis and is closely related to the occurrence and treatment of many diseases.Mitochondria in cells play a crucial role in programmed cell death and redox processes.Nicotinamide adenine dinucleotide(NAD(P)H)is the primary producer of energy in mitochondria,changing NAD(P)H can directly reflect the physiological state of mitochondria.Therefore,NAD(P)H can be used to evaluate metabolic response.In this paper,we propose a noninvasive detection method that uses two-photon fluorescence lifetime imaging microscopy(TP-FLIM)to characterize apoptosis by observing the binding kinetics of cellular endogenous NAD(P)H.The result shows that the average fluorescence lifetime of NAD(P)H and the fluorescence lifetime of protein-bound NAD(P)H will be affected by the changing pH,serum content,and oxygen concentration in the cell culture environment,and by the treatment with reagents such as H2O2 and paclitaxel.Taxol(PTX).This noninvasive detection method realized the dynamic detection of cellular endogenous substances and the assessment of apoptosis.
文摘In this work,an old scanning electron microscope(SEM)is refurbished to enhance its image processing capability.How to digitally sample and process an analog image is also presented.An NI PCI-6259 multiple input/output data acquisition(DAQ)board is used to acquire signals originally being sent to an analog display,and then convert the signals into a digital image.Two output channels are used for raster scan of the horizontal and verticle axes of the image buffer,while one input channel is used to read the brightness signals at various coordinate points.Synchronous method is used to maximize the DAQ speed.Finally,the digitally buffered images are read out to display and saved in a hard drive.The hardware and software designs of this work are explained in great detail,which can serve as a very good example for fast synchronous DAQ,advanced virtual instrument design and structural driver programming with LabVIEW.
基金supported by the National Natural Science Foundation of China,No.82272478(to PT)。
文摘Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are lacking.Emerging in vivo imaging and labeling methods offer great potential for observing dynamic neural processes in the central nervous system in conditions of health and disease.This review first discusses in vivo imaging of the mouse spinal cord with a focus on the latest imaging techniques,and then analyzes the dynamic biological response of spinal cord sensory and motor neurons to SCI.We then summarize and compare the techniques behind these studies and clarify the advantages of in vivo imaging compared with traditional neuroscience examinations.Finally,we identify the challenges and possible solutions for spinal cord neuron imaging.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.21073188).
文摘The wavelength dependence of photoelectron angular distributions (PADs) of two-photon detachment of Cu^- has been directly studied by using the photoelectron map imaging. Results show that for the laser field intensity of 6.0×10^10W/cm^2, PADs exhibit dramatic change with the external field wavelength. Comparison between the experimental observation and the lowest-order perturbation theory prediction indicates that the pattern of PADs can be explained by the interference of the s and d partial waves in the final state. Relative contri- butions of s and d partial waves in the two-photon detachment at different laser wavelengths are obtained.
基金supported by grants from Beijing Municipal Science and Technology Commission Medicine Collaborative Science and Technology Innovation Research Project(No.Z191100007719001)To Establish a Database and Study the Imaging Features of Common Skin Diseases based on Two-photon Imaging Technology(No.SK2021090379-1)
文摘Background:Pathological scars are a disorder that can lead to various cosmetic,psychological,and functional problems,and no effective assessment methods are currently available.Assessment and treatment of pathological scars are based on cutaneous manifestations.A two-photon microscope(TPM)with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo.This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients.Methods:Fifteen patients with pathological scars and three healthy controls were recruited.Imaging was performed using a portable handheld TPM.Five indexes were extracted from two dimensional(2D)and three dimensional(3D)perspectives,including collagen depth,dermo-epidermal junction(DEJ)contour ratio,thickness,orientation,and occupation(proportion of collagen fibers in the field of view)of collagen.Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images.We assessed index differences between scar and normal skin and changes before and after treatment.Results:Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers.Five indexes were employed to distinguish between normal skin and scar tissue.Statistically significant differences were found in average depth(t=9.917,P<0.001),thickness(t=4.037,P<0.001),occupation(t=2.169,P<0.050),orientation of collagen(t=3.669,P<0.001),and the DEJ contour ratio(t=5.105,P<0.001).Conclusions:Use of portable handheld TPM can distinguish collagen from skin tissues;thus,it is more suitable for scar imaging than reflectance confocal microscopy.Thus,a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.
基金Supported by the China National Science and Technology Major Project(2017ZX05009-005)the National Natural Science Foundation of China(51674271)
文摘Waterflooding experiments were performed using Micro-CT on four cores of different pore structures from Donghe sandstone reservoirs in the Tarim Basin. The water, oil and grains were accurately separated by the advanced image processing technology, the pore network model was established, and parameters such as the number of throats and the throat size distribution were calculated to characterize the microscopic heterogeneity of pore structure, the flow of oil phase during displacement, and the morphology and distribution of remaining oil after displacement. The cores with the same macroscopic porosity-permeability have great differences in microscopic heterogeneity of pore structure. Both macro porosity-permeability and micro heterogeneity of pore structure have an influence on the migration of oil phase and the morphology and distribution of remaining oil. When the heterogeneity is strong, the water phase will preferentially flow through the dominant paths and the remaining oil clusters will be formed in the small pores. The more the number of oil clusters(droplets) formed during displacement process, the smaller the average volume of cluster is, and the remaining oil is dominated by the cluster continuous phase with high saturation. The weaker the heterogeneity, the higher the pore sweep efficiency is, and the remaining oil clusters are mainly trapped in the form of non-continuous phase. The distribution and morphology of micro remaining oil are related to the absolute permeability, capillary number and micro-heterogeneity. So, the identification plate of microscopic residual oil continuity distribution established on this basis can describe the relationship between these three factors and distribution of remaining oil and identify the continuity of the remaining oil distribution accurately.
基金supported by the 863 National Plan Foundation of China under Grant No.2007AA01Z333 and Special Grand National Project of China under Grant No.2009ZX02204-008.
文摘A leukocyte image fast scanning method based on max min distance clustering is proposed.Because of the lower proportion and uneven distribution of leukocytes in human peripheral blood,there will not be any leukocyte in lager quantity of the captured images if we directly scan the blood smear along an ordinary zigzag scanning routine with high power(100^(x))objective.Due to the larger field of view of low power(10^(x))objective,the captured low power blood smear images can be used to locate leukocytes.All of the located positions make up a specific routine,if we scan the blood smear along this routine with high power objective,there will be definitely leukocytes in almost all of the captured images.Considering the number of captured images is still large and some leukocytes may be redundantly captured twice or more,a leukocyte clustering method based on max-min distance clustering is developed to reduce the total number of captured images as well as the number of redundantly captured leukocytes.This method can improve the scanning eficiency obviously.The experimental results show that the proposed method can shorten scanning time from 8.0-14.0min to 2.54.0 min while extracting 110 nonredundant individual high power leukocyte images.