Solid-liquid phase conversion between various sulfur species in lithium-sulfur(Li-S)batteries is a fundamental reaction of the sulfur cathode.Disclosing the morphological evolution of solid sulfur species upon cycling...Solid-liquid phase conversion between various sulfur species in lithium-sulfur(Li-S)batteries is a fundamental reaction of the sulfur cathode.Disclosing the morphological evolution of solid sulfur species upon cycling is of great significance to achieving high energy densities.However,an in-depth investigation of the internal reaction is still lacking.In this work,the evolution process of solid sulfur species on carbon substrates is systematically studied by using an operando light microscope combined with in situ electrochemical impedance spectra technology.The observation of phenomena such as bulk solid sulfur species can form and dissolve independently of the conductive substrates and the transformation of supercooled liquid sulfur to crystalline sulfur.Based on the phenomena mentioned above,a possible mechanism was proposed in which the dissolution reaction of solid sulfur species is a spatially free reaction that involves isotropic physical dissolution,diffusion of molecules,and finally the electrochemical reaction.Correspondingly,the formation of solid sulfur species tends to be a form of crystallization in a saturated solution rather than electrodeposition,as is commonly believed.Our findings offer new insights into the reaction of sulfur cathodes and provide new opportunities to design advanced sulfur cathodes for Li-S batteries.展开更多
In this paper,two ways of micro structural characterization,optical microscopy(OM) and polarized light microscopy(PLM),were both employed to describe the micro structure of semisolid slurry prepared by swirling enthal...In this paper,two ways of micro structural characterization,optical microscopy(OM) and polarized light microscopy(PLM),were both employed to describe the micro structure of semisolid slurry prepared by swirling enthalpy equilibration device(SEED).The results show that PLM is more reliable and accurate than OM to describe the special morphology feature of semisolid slurry made by SEED process.Meanwhile,the effects of pouring temperature and mass of molten liquid on the primary α-Al particle size and morphology were also investigated using PLM.The quantitative metallographic results measured from PLM demonstrate that the grain size and morphology and their distribution are significantly affected by both pouring temperature and the mass of molten liquid.The grain size poured with 2.7 kg liquid decreases from 659 to186 μm,and grain morphology transforms from dendrite to globular structure with pouring temperature reducing from690 to 630℃.The decreasing pouring temperature also promotes the distribution of spherical structure on the cross section.Meanwhile,the mass of molten liquid decreasing from 2.7 to 2.3 kg can decrease the grain size by maximum of 44% at high pouring temperature.展开更多
Qualification of polarization can be realized either on a macroscopic scale as an average property by P-E hysteresis measurements or on a nano/micro scale by piezoelectric force microscopy,transmission electron micros...Qualification of polarization can be realized either on a macroscopic scale as an average property by P-E hysteresis measurements or on a nano/micro scale by piezoelectric force microscopy,transmission electron microscopy,scanning electron microscopy,and so on.However,visualization and qualification of polarization distribution in the micron to millimeter scale is still a challenge.Polarizing light microscopy(PLM)is often used in the study of ferroelectric domain structures mainly for domain patterns.A phe-nomenon called“chromatic polarization”has been observed in transparent ferroelectric crystals by using a crossed-PLM system viewed with white light,which contains rich information about local polariza-tion distribution.In this study,an automatic full-angle light intensity detection(AFALID)algorithm com-bined with colorimetry is developed to analyze the distribution of nonuniform local spontaneous polar-ization distribution in transparent ferroelectric single crystals.Temperature-dependent spontaneous po-larizations from the color analysis for PMN-0.36PT single crystals with single tetragonal domain state are in good coincidence with those extracted from temperature-dependent hysteresis loops and pyroelectric current measurements.We further apply this method to quantify the nonuniform domain distributions with nano-indentations.This non-contact and non-destructive characterization can provide fast and au-tomatic detection of polarization distributions in ferroelectric materials.展开更多
We present a threedimensional(3D)isotropic imaging of mouse brain using light-sheet fuo-rescent microscopy(LSFM)in conjumction with a multi-view imaging computation.Unlike common single view LSFM is used for mouse bra...We present a threedimensional(3D)isotropic imaging of mouse brain using light-sheet fuo-rescent microscopy(LSFM)in conjumction with a multi-view imaging computation.Unlike common single view LSFM is used for mouse brain imaging,the brain tissue is 3D imaged under eight views in our study,by a home-built selective plane ilumination microscopy(SPIM).An output image containing complete structural infornation as well as significantly improved res olution(~4 times)are then computed based on these eight views of data,using a bead-guided multi-view registration and deconvolution.With superior imaging quality,the astrocyte and pyrarmidal neurons together with their subcellular nerve fbers can be clearly visualized and segmented.With further incuding other computational methods,this study can be potentially scaled up to map the conectome of whole mouse brain with a simple light.sheet microscope.展开更多
Recording the highly diverse and dynamic activities in large populations of neurons in behaving animals is crucial for a better understanding of how the brain works.To meet this challenge,extensive efforts have been d...Recording the highly diverse and dynamic activities in large populations of neurons in behaving animals is crucial for a better understanding of how the brain works.To meet this challenge,extensive efforts have been devoted to developing functional fluorescent indicators and optical imaging techniques to optically monitor neural activity.Indeed,optical imaging potentially has extremely high throughput due to its non-invasive access to large brain regions and capability to sample neurons at high density,but the readout speed,such as the scanning speed in two-photon scanning microscopy,is often limited by various practical considerations.Among different imaging methods,light field microscopy features a highly parallelized 3D fluorescence imaging scheme and therefore promises a novel and faster strategy for functional imaging of neural activity.Here,we briefly review the working principles of various types of light field microscopes and their recent developments and applications in neuroscience studies.We also discuss strategies and considerations of optimizing light field microscopy for different experimental purposes,with illustrative examples in imaging zebrafish and mouse brains.展开更多
Single-cell volumetric imaging is essential for researching individual characteristics of cells.As a nonscanning imaging technique,lighteld microscopy(LFM)is a critical tool to achieve realtime three-dimensional imagi...Single-cell volumetric imaging is essential for researching individual characteristics of cells.As a nonscanning imaging technique,lighteld microscopy(LFM)is a critical tool to achieve realtime three-dimensional imaging with the advantage of single-shot.To address the inherent limits including nonuniform resolution and block-wise artifacts,various modied LFM strategies have been developed to provide new insights into the structural and functional information of cells.This review will introduce the principle and development of LFM,discuss the improved approaches based on hardware designs and 3D reconstruction algorithms,and present the applications in single-cell imaging.展开更多
Exposure to respirable coal mine dust(RCMD)can cause chronic and debilitating lung diseases.Real-time monitoring capabilities are sought which can enable a better understanding of dust components and sources.In many u...Exposure to respirable coal mine dust(RCMD)can cause chronic and debilitating lung diseases.Real-time monitoring capabilities are sought which can enable a better understanding of dust components and sources.In many underground mines,RCMD includes three primary components which can be loosely associated with three major dust sources:coal dust from the coal seam itself,silicates from the surrounding rock strata,and carbonates from the inert‘rock dust’products that are applied to mitigate explosion hazards.A monitor which can reliably partition RCMD between these three components could thus allow source apportionment.And tracking silicates,specifically,could be valuable since the most serious health risks are typically associated with this component-particularly if abundant in crystalline silica.Envisioning a monitoring concept based on field microscopy,and following up on prior research using polarized light,the aim of the current study was to build and test a model to classify respirable-sized particles as either coal,silicates,or carbonates.For model development,composite dust samples were generated in the laboratory by successively depositing dust from high-purity materials onto a sticky transparent substrate,and imaging after each deposition event such that the identity of each particle was known a priori.Model testing followed a similar approach,except that real geologic materials were used as the source for each dust component.Results showed that the model had an overall accuracy of 86.5%,indicating that a field-microscopy based moni-tor could support RCMD source apportionment and silicates tracking in some coal mines.展开更多
By using light and electron microscopic cytochemical technique, the activities and distributions of AP isoenzymes in gastric cancers and benign gastric diseases were examined.The results showed: Nagao, Regan and Kasah...By using light and electron microscopic cytochemical technique, the activities and distributions of AP isoenzymes in gastric cancers and benign gastric diseases were examined.The results showed: Nagao, Regan and Kasahara isoenzymes, which were not expressed in normal gastric mucosae and non-malignant lesions, might be considered as tumor markers of gastric cancer;The epithelium of intestinal metaplasia exhibited intestinal-type AP only,which was one of the markers of well-differentiated intestinal metaplasia.In the view-point of the gene expression of AP isoenzymes, two mutation hypothesis and recessive-gene mutation hypothesis might be fit for gastric cancer.展开更多
[Objective]The antidepressant mechanism of EA in repairing damaged areas of astrocytes. [Methods]66 adult female SD rats were randomly divided into four groups. The normal control group only for normal feeding, the ot...[Objective]The antidepressant mechanism of EA in repairing damaged areas of astrocytes. [Methods]66 adult female SD rats were randomly divided into four groups. The normal control group only for normal feeding, the other three groups adopt long-term chronic unpredictable mild stimulation singly housed jointly, establishing model of depression. Blank group, atter modeling successfully with no treatment; electro-acupuncture group, in the successful modeling begins the day after electro-acupuncture treatment four passes points, selecting a continuous wave electro-acupuncture device, alternating left and right points, continuous 21 days. Drug group, on the day after the successful modeling garage given riluzole treatment, continuous treatment for 3 weeks.Rats were sacrificed by dislocation, taking hippocampal tissue under light microscope. [Results]Tile modeling light microscope rat hippocampus astrocytes significant change in the number and morphology, and the normal control group, the difference was statistically significant （P 〈0.05）; 3 weeks after treatment, the drug rats number of hippocampal astrocytes increased significantly, normal hippocampus pyramidal cells and astrocytes karyopyknosis partial recovery, compared with the control group, the difference was statistically significant; CAI region of rats EA, DG district star shaped glial cell number increased, compared with the control group, the difference was statistically significant, compared with the drug showed no significant difference （P〉 0.05）; electToacupuncture group number CA3 region astrocytes no significant increase, with the drug group, the difference was statistically significant （P = 0.032）, in the control group and the normal control group, the difference was not statistically significant （P〉 0.05）. [Conclusion]EA can fix the depression caused by chronic stress hippocampal astrocytes injury, and similar efficacy with riluzole, which may be an important way for the antidepressant of EA.展开更多
Airborne microplastics(MPs)are important pollutants that have been present in the environment for many years and are characterized by their universality,persistence,and potential toxicity.This study investigated the e...Airborne microplastics(MPs)are important pollutants that have been present in the environment for many years and are characterized by their universality,persistence,and potential toxicity.This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime.Laser direct infrared imaging(LDIR)and polarized light microscopy were used to characterize the physical and chemical properties of MPs,including number concentration,chemical types,shape,and size.Backward trajectories were used to distinguish the air masses from marine and terrestrial transport.Twenty chemical types were detected by LDIR,with rubber(16.7%)and phenol-formaldehyde resin(PFR;14.8%)being major components.Three main morphological types of MPs were identified,and fragments(78.1%)are the dominant type.MPs in the atmosphere were concentrated in the small particle size segment(20-50μm).The concentration of MPs in the air mass from marine transport was 14.7 items/m^(3)-lower than that from terrestrial transport(32.0 items/m^(3)).The number concentration of airborne MPs was negatively correlated with relative humidity.MPs from terrestrial transport were mainly rubber(20.2%),while those from marine transport were mainly PFR(18%).MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass.The number concentration of airborne MPs is higher during the day than at night.These findings could contribute to the development of targeted control measures and methods to reduce MP pollution.展开更多
Spinal motoneurons control muscle fibers contraction and drive all motor behaviors in vertebrates.Although spinal motoneurons share the fundamental role of innervating muscle fibers,they exhibit remarkable diversity t...Spinal motoneurons control muscle fibers contraction and drive all motor behaviors in vertebrates.Although spinal motoneurons share the fundamental role of innervating muscle fibers,they exhibit remarkable diversity that reflects their specific identities.Defining the morphological changes during postnatal development is critical for elucidating this diversity.However,our understanding of the three-dimensional(3D)morphology of spinal motoneurons at these stages remains limited,largely due to the lack of high-throughput imaging tools.Using tiling light sheet microscopy combined with tissue clearing methods,we imaged motoneurons of the lateral and median motor column in the cervical and lumbar cord during postnatal development.By analyzing their soma size,we found that motoneurons innervating the upper limbs differentiate into two subpopulations with distinct soma size by postnatal day 14(P14),while differentiation of motoneurons innervating the lower limbs is delayed.Furthermore,coupling adenovirus labeling with 3D volumetric reconstruction,we traced and measured the number and lengths of dendrites of flexor and extensor motoneurons in the lumbar cord,finding that the number of dendrites initially increases and subsequently declines as dendritic order rises.Together,these findings provide a quantitative analysis of the 3D morphological changes underlying spinal motoneuron diversity.展开更多
Time-resolved volumetric fluorescence imaging over an extended duration with high spatial/temporal resolution is a key driving force in biomedical research for investigating spatial-temporal dynamics at organism-level...Time-resolved volumetric fluorescence imaging over an extended duration with high spatial/temporal resolution is a key driving force in biomedical research for investigating spatial-temporal dynamics at organism-level systems,yet it remains a major challenge due to the trade-off among imaging speed,light exposure,illumination power,and image quality.Here,we present a deep-learning enhanced light sheet fluorescence microscopy(LSFM)approach that addresses the restoration of rapid volumetric time-lapse imaging with less than 0.03%light exposure and 3.3%acquisition time compared to a typical standard acquisition.We demonstrate that the convolutional neural network(CNN)-transformer network developed here,namely U-net integrated transformer(UI-Trans),successfully achieves the mitigation of complex noise-scattering-coupled degradation and outperforms state-of-the-art deep learning networks,due to its capability of faithfully learning fine details while comprehending complex global features.With the fast generation of appropriate training data via flexible switching between confocal line-scanning LSFM(LS-LSFM)and conventional LSFM,this method achieves a three-to five-fold signal-to-noise ratio(SNR)improvement and~1.8 times contrast improvement in ex vivo zebrafish heart imaging and long-term in vivo 4D(3D morphology+time)imaging of heartbeat dynamics at different developmental stages with ultra-economical acquisitions in terms of light dosage and acquisition time.展开更多
Light-field microscopy(LFM)enables rapid volumetric imaging through single-frame acquisition and fast 3D reconstruction algorithms.The high speed and low phototoxicity of LFM make it highly suitable for real-time 3D f...Light-field microscopy(LFM)enables rapid volumetric imaging through single-frame acquisition and fast 3D reconstruction algorithms.The high speed and low phototoxicity of LFM make it highly suitable for real-time 3D fluorescence imaging,such as studies of neural activity monitoring and blood flow analysis.However,in in vivo fluorescence imaging scenarios,the light intensity needs to be reduced as much as possible to achieve longer-term observations.The resulting low signal-to-noise ratio(SNR)caused by reduced light intensity significantly degrades the quality of 3D reconstruction in LFM.Existing deep-learning-based methods struggle to incorporate the structured intensity distribution and noise characteristics inherent to LFM data,often leading to artifacts and uneven energy distributions.To address these challenges,we propose the denoise-weighted view-channel-depth(DNW-VCD)network,integrating a two-step noise model and energy weight matrix into an LFM reconstruction framework.Additionally,we developed an attenuator-induced imaging system for dual-SNR image acquisition to validate DNW-VCD’s performance.Experimental results show that our method achieves artifact-reduced,realtime 3D imaging with isotropic resolution and lower phototoxicity,as verified through imaging of fluorescent beads,algae,and zebrafish heart.展开更多
The low-cost petroleum pitch and waste polyethylene （WPE） were used as raw materials to prepare the mesophase pitch by co-carbonization method and the forming mechanization of mesophase pitch was also investigated. ...The low-cost petroleum pitch and waste polyethylene （WPE） were used as raw materials to prepare the mesophase pitch by co-carbonization method and the forming mechanization of mesophase pitch was also investigated. Polarized microscopy, softening point, Fourier transform infrared spectroscopy （FTIR） and thermogravimetric analysis （TGA） were used to characterize and analyze the properties and struc- ture of the mesophase pitch. The results showed that the carbonization yield of the modified pitch was high when 1-2 wt% WPE was added and the property of mesophase pitch （MP1-450-4 and MP2-450-4） prepared by thermal polymerization was excellent. Moreover, when the treatment temperature was above 420 ~C, the mesophase development of the modified pitch may be entire and 100% streamline texture mesophase can form. During the co-carbonization of WPEJpetroleum pitch, a large number of naphthenic structures and methylene bridges may be generated, which can improve the properties of the obtained mesophase pitch.展开更多
A two-step technology combined forging with superplastic forming has been developed to enhance the forgeability of semi-continuously cast AZ70 magnesium alloy and realize the application of the as-cast magnesium alloy...A two-step technology combined forging with superplastic forming has been developed to enhance the forgeability of semi-continuously cast AZ70 magnesium alloy and realize the application of the as-cast magnesium alloy in large deformation bullet shell.In the first step,fine-grained microstructure preforms that are suitable for superplastic forming were obtained by reasonably designing the size of the initial blanks with the specific height-to-diameter ratio,upsetting the blanks and subsequent annealing.In the second step,the heat treated preforms were forged into the end products at the superplastic conditions.The end products exhibit high quality surface and satisfied microstructure.Consequently,this forming technology that not only avoids complicating the material preparation but also utilizes higher strain rate superplastic provides a near net-shaped novel method on magnesium forging forming technology using as-cast billet.展开更多
Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this s...Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this study,six lacustrine shale samples with different thermal maturities from the first member of the Qingshankou Formation in the Songliao Basin,of which vitrinite reflectance(R_(o))ranging from 0.58% to 1.43%,were selected for a comparative analysis.Scanning electron microscopy(SEM)and reflected light microscopy were combined to investigate the development of organic pores in different macerals during thermal maturation.The results show that alginite and liptodetrinite are the dominant primary macerals,followed by bituminite.Only a few primary organic pores developed in the alginite at the lowest maturity(R_(o)=0.58%).As a result of petroleum generation,oil-prone macerals began to transform to initial-oil solid bitumen at the early oil window(R_(o)=0.73%)and shrinkage cracks were observed.Initial-oil solid bitumen cracked to oil,gas and post-oil bitumen by primary cracking(R_(o)=0.98%).Moreover,solid bitumen(SB)was found to be the dominant OM when R_(o)>0.98%,which indicates that SB is the product of oil-prone macerals transformation.Many secondary bubble pores were observed on SB,which formed by gas release,while devolatilization cracks developed on migrated SB.Additionally,at the late oil window(Ro?1.16%),migrated SB filled the interparticle pore spaces.With further increase in temperature,the liquid oil underwent secondary cracking into pyrobitumen and gas,and spongy pores developed on the pyrobitumen at higher levels of maturity(Ro=1.43%),which formed when pyrobitumen cracked into gas.Vitrinite and inertinite are stable without any visible pores over the range of maturities,verifying their low petroleum generation potential.In addition,it was concluded that clay minerals could have a catalytic effect on the petroleum generation,which may explain why organicclay mixtures had more abundant pores than single OM particles.However,after R_(o)>0.98%,authigenic minerals occupied the organic pore spaces on the organic-clay mixtures,resulting in fewer pores compared to those observed in samples at the early to peak oil window.展开更多
The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various...The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental conditions.Today,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience research.In this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining methods.Considering the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.展开更多
AIM:To investigate the side effects of the commonly used laser treatment along with testing the neuroprotective effect of bFGF on a potential retinal impairment.METHODS:To do this,30 chinchilla pigmented adult male ra...AIM:To investigate the side effects of the commonly used laser treatment along with testing the neuroprotective effect of bFGF on a potential retinal impairment.METHODS:To do this,30 chinchilla pigmented adult male rabbits were divided into the control and experimental groups.The control and experimental groups underwent both laser application and bFGF treatment.The retinal tissue impairment and its renewal rate were tested under the light and electron microscopical levels.RESULTS:The focal laser application on rabbit eyes caused morphological alterations both in the application region and in the neighbouring areas.In the damaged areas,the outer nuclear layer of the neural retina was almost disappeared,retina pigment epithelium was interrupted,the retina pigment epithelium migrated intraretinally,and the damaged region along with neighbouring areas seemed to be not separated.bFGF application just after the laser photocoagulation,revealed better results in application areas.CONCLUSION:It could be suggested that the bFGF application following laser photocoagulation might have protective,repairing and wound healing effects on the retina.展开更多
In the present study, histopathology of three varieties of sesame TS 3, TS 5 and SG 27 infected with Alternaria alternata was carried out to understand the mechanism of fungal infection and penetration in sesame plant...In the present study, histopathology of three varieties of sesame TS 3, TS 5 and SG 27 infected with Alternaria alternata was carried out to understand the mechanism of fungal infection and penetration in sesame plant as well as to determine the histological manifestation in sesame cells by light microscopy. Fungus was identified in infected tissues as a dark bluish black with toluidine blue O staining. Light microscopic examination of sesame stem showed that the fungus was present in epidermis, hypodermis and cortical parenchyma tissue as the symptoms became visible by naked eye ten days after inoculation (DAI). As the disease progress, the fungus moved from cortical parenchyma to vascular bundle, xylem and phloem. Later on, it completely overlapped the vascular bundle and entered in pith. When necrotic lesion appeared, fungus was present abundantly in epidermis, hypodermis, cortical parenchyma, vascular bundles and in pith. Due to its excessive growth and complete overlapping of cells, disorganization or destruction of cells of sesame took place. It was concluded that the Alternaria alternata was not a tissue limited pathogen instead of this it spread in to all tissues of stem from epidermis to pith.展开更多
Background: Worldwide, diabetic nephropathy-DN is the leading cause of end-stage kidney disease-ESKD, DN is a common cause of renal failure with a reported frequency of 10% - 15% in type-2-diabetes-mellitus-T2DM patie...Background: Worldwide, diabetic nephropathy-DN is the leading cause of end-stage kidney disease-ESKD, DN is a common cause of renal failure with a reported frequency of 10% - 15% in type-2-diabetes-mellitus-T2DM patients, however there is a great discrepancy between countries. The aim of the pre-sent study is to evaluate the findings of kidney biopsies performed on diabetic patients. Materials and Methods: We studied native kidney histopathological findings in the period from January 2016 till end of December 2018 done for patients with T2DM with chronic kidney diseases-CKD. Results: A total of 82 DM-patients, 50 males (61%) and 32 females (39%) with age mean (95% CI) of 50.8 (47.1 - 55.2) years for all patients, ranged between 15 to 65 years. Histological findings showed that 57.3% of patients had DN. While focal-segmental-glomerulosclerosis-FSGS was present in 20.7%—primary in 8.6% and secondary in 12.1%. IgA represented 4.9%, while Lupus nephritis, Membranous and drug induced interstitial nephritis were each present in 3.7%. MCD was present in 2.4%. Lastly diffuse proliferative GN, ANCA associated glomerulonephritis, and hypertensive nephrosclerosis accounted for 1.2%. Conclusion: The prevalence of NDKD is remarkably frequent in DM patients who underwent kidney biopsy and FSGS was the most frequent diagnosis. To get a proper histopathological diagnosis, an adequate tissue biopsy is needed with an adequate number of glomeruli. There is a great need for more consideration to biopsy diabetic patients, as the finding of NDKD requires a different therapeutic approach. This, hopefully, will help to manage these patients better and therefore, ameliorate the progression to ESKD over time and therefore delay the need for RRT.展开更多
基金the financial support from The National Key Research and Development Program of China(2018YFB0104200)。
文摘Solid-liquid phase conversion between various sulfur species in lithium-sulfur(Li-S)batteries is a fundamental reaction of the sulfur cathode.Disclosing the morphological evolution of solid sulfur species upon cycling is of great significance to achieving high energy densities.However,an in-depth investigation of the internal reaction is still lacking.In this work,the evolution process of solid sulfur species on carbon substrates is systematically studied by using an operando light microscope combined with in situ electrochemical impedance spectra technology.The observation of phenomena such as bulk solid sulfur species can form and dissolve independently of the conductive substrates and the transformation of supercooled liquid sulfur to crystalline sulfur.Based on the phenomena mentioned above,a possible mechanism was proposed in which the dissolution reaction of solid sulfur species is a spatially free reaction that involves isotropic physical dissolution,diffusion of molecules,and finally the electrochemical reaction.Correspondingly,the formation of solid sulfur species tends to be a form of crystallization in a saturated solution rather than electrodeposition,as is commonly believed.Our findings offer new insights into the reaction of sulfur cathodes and provide new opportunities to design advanced sulfur cathodes for Li-S batteries.
基金financially supported by the National Key Research and Development Program of China (No. 2016YFB0301003)the Shenzhen Free Exploring Basic Research Project (No. JCYJ20170307110223452)。
文摘In this paper,two ways of micro structural characterization,optical microscopy(OM) and polarized light microscopy(PLM),were both employed to describe the micro structure of semisolid slurry prepared by swirling enthalpy equilibration device(SEED).The results show that PLM is more reliable and accurate than OM to describe the special morphology feature of semisolid slurry made by SEED process.Meanwhile,the effects of pouring temperature and mass of molten liquid on the primary α-Al particle size and morphology were also investigated using PLM.The quantitative metallographic results measured from PLM demonstrate that the grain size and morphology and their distribution are significantly affected by both pouring temperature and the mass of molten liquid.The grain size poured with 2.7 kg liquid decreases from 659 to186 μm,and grain morphology transforms from dendrite to globular structure with pouring temperature reducing from690 to 630℃.The decreasing pouring temperature also promotes the distribution of spherical structure on the cross section.Meanwhile,the mass of molten liquid decreasing from 2.7 to 2.3 kg can decrease the grain size by maximum of 44% at high pouring temperature.
基金This work is financially supported by the National Key Re-search and Development Program of China(No.2021YFF0501001)the Heilongjiang Provincial Natural Science Foundation of China(No.LH2020A006)the Open Fund of Key Laboratory for In-telligent Nano Materials and Devices of the Ministry of Education NJ2022002(No.INMD-2022M08).
文摘Qualification of polarization can be realized either on a macroscopic scale as an average property by P-E hysteresis measurements or on a nano/micro scale by piezoelectric force microscopy,transmission electron microscopy,scanning electron microscopy,and so on.However,visualization and qualification of polarization distribution in the micron to millimeter scale is still a challenge.Polarizing light microscopy(PLM)is often used in the study of ferroelectric domain structures mainly for domain patterns.A phe-nomenon called“chromatic polarization”has been observed in transparent ferroelectric crystals by using a crossed-PLM system viewed with white light,which contains rich information about local polariza-tion distribution.In this study,an automatic full-angle light intensity detection(AFALID)algorithm com-bined with colorimetry is developed to analyze the distribution of nonuniform local spontaneous polar-ization distribution in transparent ferroelectric single crystals.Temperature-dependent spontaneous po-larizations from the color analysis for PMN-0.36PT single crystals with single tetragonal domain state are in good coincidence with those extracted from temperature-dependent hysteresis loops and pyroelectric current measurements.We further apply this method to quantify the nonuniform domain distributions with nano-indentations.This non-contact and non-destructive characterization can provide fast and au-tomatic detection of polarization distributions in ferroelectric materials.
基金funding support from 1000 Youth Talents Plan of China (P.F.)Fundamental Research Program of Shenzhen (P.F.,JCYJ20160429182424047)+1 种基金National Science Foundation of China (NSFC31571002,D.Z)Graduates'Innovation Fund of Huazhong University of Science and Technology (5003182004).
文摘We present a threedimensional(3D)isotropic imaging of mouse brain using light-sheet fuo-rescent microscopy(LSFM)in conjumction with a multi-view imaging computation.Unlike common single view LSFM is used for mouse brain imaging,the brain tissue is 3D imaged under eight views in our study,by a home-built selective plane ilumination microscopy(SPIM).An output image containing complete structural infornation as well as significantly improved res olution(~4 times)are then computed based on these eight views of data,using a bead-guided multi-view registration and deconvolution.With superior imaging quality,the astrocyte and pyrarmidal neurons together with their subcellular nerve fbers can be clearly visualized and segmented.With further incuding other computational methods,this study can be potentially scaled up to map the conectome of whole mouse brain with a simple light.sheet microscope.
基金This work was supported by grants from the National Science and Technology Innovation 2030 Major Program(2021ZD0204503)National Key R&D Program of China(2017YFA0700504)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB32030200)the International Partnership Program of the Chinese Academy of Sciences(153D31KYSB20170059)Shanghai Municipal Science and Technology Major Project(2018SHZDZX05)the National Natural Science Foundation of China(31871086 and 32125020).
文摘Recording the highly diverse and dynamic activities in large populations of neurons in behaving animals is crucial for a better understanding of how the brain works.To meet this challenge,extensive efforts have been devoted to developing functional fluorescent indicators and optical imaging techniques to optically monitor neural activity.Indeed,optical imaging potentially has extremely high throughput due to its non-invasive access to large brain regions and capability to sample neurons at high density,but the readout speed,such as the scanning speed in two-photon scanning microscopy,is often limited by various practical considerations.Among different imaging methods,light field microscopy features a highly parallelized 3D fluorescence imaging scheme and therefore promises a novel and faster strategy for functional imaging of neural activity.Here,we briefly review the working principles of various types of light field microscopes and their recent developments and applications in neuroscience studies.We also discuss strategies and considerations of optimizing light field microscopy for different experimental purposes,with illustrative examples in imaging zebrafish and mouse brains.
基金This paper was supported by Shenzhen Science and Technology Innovation grants(JCYJ20200109115633343,JCYJ20210324123610030).
文摘Single-cell volumetric imaging is essential for researching individual characteristics of cells.As a nonscanning imaging technique,lighteld microscopy(LFM)is a critical tool to achieve realtime three-dimensional imaging with the advantage of single-shot.To address the inherent limits including nonuniform resolution and block-wise artifacts,various modied LFM strategies have been developed to provide new insights into the structural and functional information of cells.This review will introduce the principle and development of LFM,discuss the improved approaches based on hardware designs and 3D reconstruction algorithms,and present the applications in single-cell imaging.
基金supported by the Alpha Foundation for the Improvement of Mine Safety and Health,grant number AFC316FO-84.
文摘Exposure to respirable coal mine dust(RCMD)can cause chronic and debilitating lung diseases.Real-time monitoring capabilities are sought which can enable a better understanding of dust components and sources.In many underground mines,RCMD includes three primary components which can be loosely associated with three major dust sources:coal dust from the coal seam itself,silicates from the surrounding rock strata,and carbonates from the inert‘rock dust’products that are applied to mitigate explosion hazards.A monitor which can reliably partition RCMD between these three components could thus allow source apportionment.And tracking silicates,specifically,could be valuable since the most serious health risks are typically associated with this component-particularly if abundant in crystalline silica.Envisioning a monitoring concept based on field microscopy,and following up on prior research using polarized light,the aim of the current study was to build and test a model to classify respirable-sized particles as either coal,silicates,or carbonates.For model development,composite dust samples were generated in the laboratory by successively depositing dust from high-purity materials onto a sticky transparent substrate,and imaging after each deposition event such that the identity of each particle was known a priori.Model testing followed a similar approach,except that real geologic materials were used as the source for each dust component.Results showed that the model had an overall accuracy of 86.5%,indicating that a field-microscopy based moni-tor could support RCMD source apportionment and silicates tracking in some coal mines.
文摘By using light and electron microscopic cytochemical technique, the activities and distributions of AP isoenzymes in gastric cancers and benign gastric diseases were examined.The results showed: Nagao, Regan and Kasahara isoenzymes, which were not expressed in normal gastric mucosae and non-malignant lesions, might be considered as tumor markers of gastric cancer;The epithelium of intestinal metaplasia exhibited intestinal-type AP only,which was one of the markers of well-differentiated intestinal metaplasia.In the view-point of the gene expression of AP isoenzymes, two mutation hypothesis and recessive-gene mutation hypothesis might be fit for gastric cancer.
文摘[Objective]The antidepressant mechanism of EA in repairing damaged areas of astrocytes. [Methods]66 adult female SD rats were randomly divided into four groups. The normal control group only for normal feeding, the other three groups adopt long-term chronic unpredictable mild stimulation singly housed jointly, establishing model of depression. Blank group, atter modeling successfully with no treatment; electro-acupuncture group, in the successful modeling begins the day after electro-acupuncture treatment four passes points, selecting a continuous wave electro-acupuncture device, alternating left and right points, continuous 21 days. Drug group, on the day after the successful modeling garage given riluzole treatment, continuous treatment for 3 weeks.Rats were sacrificed by dislocation, taking hippocampal tissue under light microscope. [Results]Tile modeling light microscope rat hippocampus astrocytes significant change in the number and morphology, and the normal control group, the difference was statistically significant （P 〈0.05）; 3 weeks after treatment, the drug rats number of hippocampal astrocytes increased significantly, normal hippocampus pyramidal cells and astrocytes karyopyknosis partial recovery, compared with the control group, the difference was statistically significant; CAI region of rats EA, DG district star shaped glial cell number increased, compared with the control group, the difference was statistically significant, compared with the drug showed no significant difference （P〉 0.05）; electToacupuncture group number CA3 region astrocytes no significant increase, with the drug group, the difference was statistically significant （P = 0.032）, in the control group and the normal control group, the difference was not statistically significant （P〉 0.05）. [Conclusion]EA can fix the depression caused by chronic stress hippocampal astrocytes injury, and similar efficacy with riluzole, which may be an important way for the antidepressant of EA.
基金supported by the National Natural Science Foundation of China (No.42075107)the Fundamental Research Funds for the Central Universities (No.2022YJSDC05)+1 种基金the China Scholarship Council (No.202206430058)the Yueqi Scholar Fund of China University of Mining and Technology (Beijing).
文摘Airborne microplastics(MPs)are important pollutants that have been present in the environment for many years and are characterized by their universality,persistence,and potential toxicity.This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime.Laser direct infrared imaging(LDIR)and polarized light microscopy were used to characterize the physical and chemical properties of MPs,including number concentration,chemical types,shape,and size.Backward trajectories were used to distinguish the air masses from marine and terrestrial transport.Twenty chemical types were detected by LDIR,with rubber(16.7%)and phenol-formaldehyde resin(PFR;14.8%)being major components.Three main morphological types of MPs were identified,and fragments(78.1%)are the dominant type.MPs in the atmosphere were concentrated in the small particle size segment(20-50μm).The concentration of MPs in the air mass from marine transport was 14.7 items/m^(3)-lower than that from terrestrial transport(32.0 items/m^(3)).The number concentration of airborne MPs was negatively correlated with relative humidity.MPs from terrestrial transport were mainly rubber(20.2%),while those from marine transport were mainly PFR(18%).MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass.The number concentration of airborne MPs is higher during the day than at night.These findings could contribute to the development of targeted control measures and methods to reduce MP pollution.
基金supported by Westlake Education Foundation,the National Natural Science Foundation of China(32150015)the Zhejiang Province Natural Science Foundation(LR20 C070002).
文摘Spinal motoneurons control muscle fibers contraction and drive all motor behaviors in vertebrates.Although spinal motoneurons share the fundamental role of innervating muscle fibers,they exhibit remarkable diversity that reflects their specific identities.Defining the morphological changes during postnatal development is critical for elucidating this diversity.However,our understanding of the three-dimensional(3D)morphology of spinal motoneurons at these stages remains limited,largely due to the lack of high-throughput imaging tools.Using tiling light sheet microscopy combined with tissue clearing methods,we imaged motoneurons of the lateral and median motor column in the cervical and lumbar cord during postnatal development.By analyzing their soma size,we found that motoneurons innervating the upper limbs differentiate into two subpopulations with distinct soma size by postnatal day 14(P14),while differentiation of motoneurons innervating the lower limbs is delayed.Furthermore,coupling adenovirus labeling with 3D volumetric reconstruction,we traced and measured the number and lengths of dendrites of flexor and extensor motoneurons in the lumbar cord,finding that the number of dendrites initially increases and subsequently declines as dendritic order rises.Together,these findings provide a quantitative analysis of the 3D morphological changes underlying spinal motoneuron diversity.
基金supported by National Natural Science Foundation of China(52122008,52270008,52370003,62025502)Guangdong Introducing Innovative and Entrepreneurial Teams of“The Pearl River Talent Recruitment Program”(2021ZT09X044)Shenzhen Technology University under Grant JSZZ202301010.
文摘Time-resolved volumetric fluorescence imaging over an extended duration with high spatial/temporal resolution is a key driving force in biomedical research for investigating spatial-temporal dynamics at organism-level systems,yet it remains a major challenge due to the trade-off among imaging speed,light exposure,illumination power,and image quality.Here,we present a deep-learning enhanced light sheet fluorescence microscopy(LSFM)approach that addresses the restoration of rapid volumetric time-lapse imaging with less than 0.03%light exposure and 3.3%acquisition time compared to a typical standard acquisition.We demonstrate that the convolutional neural network(CNN)-transformer network developed here,namely U-net integrated transformer(UI-Trans),successfully achieves the mitigation of complex noise-scattering-coupled degradation and outperforms state-of-the-art deep learning networks,due to its capability of faithfully learning fine details while comprehending complex global features.With the fast generation of appropriate training data via flexible switching between confocal line-scanning LSFM(LS-LSFM)and conventional LSFM,this method achieves a three-to five-fold signal-to-noise ratio(SNR)improvement and~1.8 times contrast improvement in ex vivo zebrafish heart imaging and long-term in vivo 4D(3D morphology+time)imaging of heartbeat dynamics at different developmental stages with ultra-economical acquisitions in terms of light dosage and acquisition time.
基金National Natural Science Foundation of China(T2221003,62025108,62071219,62371006)China Postdoctoral Science Foundation(GZC20230057)。
文摘Light-field microscopy(LFM)enables rapid volumetric imaging through single-frame acquisition and fast 3D reconstruction algorithms.The high speed and low phototoxicity of LFM make it highly suitable for real-time 3D fluorescence imaging,such as studies of neural activity monitoring and blood flow analysis.However,in in vivo fluorescence imaging scenarios,the light intensity needs to be reduced as much as possible to achieve longer-term observations.The resulting low signal-to-noise ratio(SNR)caused by reduced light intensity significantly degrades the quality of 3D reconstruction in LFM.Existing deep-learning-based methods struggle to incorporate the structured intensity distribution and noise characteristics inherent to LFM data,often leading to artifacts and uneven energy distributions.To address these challenges,we propose the denoise-weighted view-channel-depth(DNW-VCD)network,integrating a two-step noise model and energy weight matrix into an LFM reconstruction framework.Additionally,we developed an attenuator-induced imaging system for dual-SNR image acquisition to validate DNW-VCD’s performance.Experimental results show that our method achieves artifact-reduced,realtime 3D imaging with isotropic resolution and lower phototoxicity,as verified through imaging of fluorescent beads,algae,and zebrafish heart.
基金supported by the National Natural Science Foundation of China(Grant Nos.51172180 and 51372200)Program for New Century Excellent Talents in University of the Ministry of Education of China(Grant No.NCET-12-1045)+1 种基金Science and Technology Plan of Xi'an(Grant No.CXY1430(9))Shaanxi Program for Outstanding Youth Project in 2011
文摘The low-cost petroleum pitch and waste polyethylene （WPE） were used as raw materials to prepare the mesophase pitch by co-carbonization method and the forming mechanization of mesophase pitch was also investigated. Polarized microscopy, softening point, Fourier transform infrared spectroscopy （FTIR） and thermogravimetric analysis （TGA） were used to characterize and analyze the properties and struc- ture of the mesophase pitch. The results showed that the carbonization yield of the modified pitch was high when 1-2 wt% WPE was added and the property of mesophase pitch （MP1-450-4 and MP2-450-4） prepared by thermal polymerization was excellent. Moreover, when the treatment temperature was above 420 ~C, the mesophase development of the modified pitch may be entire and 100% streamline texture mesophase can form. During the co-carbonization of WPEJpetroleum pitch, a large number of naphthenic structures and methylene bridges may be generated, which can improve the properties of the obtained mesophase pitch.
基金The National Natural Science Foundation of China(No.51171174)the National Key Technology R&D Program of China(No.2012BAI18B01)supported this study.
文摘A two-step technology combined forging with superplastic forming has been developed to enhance the forgeability of semi-continuously cast AZ70 magnesium alloy and realize the application of the as-cast magnesium alloy in large deformation bullet shell.In the first step,fine-grained microstructure preforms that are suitable for superplastic forming were obtained by reasonably designing the size of the initial blanks with the specific height-to-diameter ratio,upsetting the blanks and subsequent annealing.In the second step,the heat treated preforms were forged into the end products at the superplastic conditions.The end products exhibit high quality surface and satisfied microstructure.Consequently,this forming technology that not only avoids complicating the material preparation but also utilizes higher strain rate superplastic provides a near net-shaped novel method on magnesium forging forming technology using as-cast billet.
基金financially supported by the National Natural Science Foundation of China(41972156)the Natural Science Foundation of Heilongjiang Province(TD 2021D001).
文摘Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this study,six lacustrine shale samples with different thermal maturities from the first member of the Qingshankou Formation in the Songliao Basin,of which vitrinite reflectance(R_(o))ranging from 0.58% to 1.43%,were selected for a comparative analysis.Scanning electron microscopy(SEM)and reflected light microscopy were combined to investigate the development of organic pores in different macerals during thermal maturation.The results show that alginite and liptodetrinite are the dominant primary macerals,followed by bituminite.Only a few primary organic pores developed in the alginite at the lowest maturity(R_(o)=0.58%).As a result of petroleum generation,oil-prone macerals began to transform to initial-oil solid bitumen at the early oil window(R_(o)=0.73%)and shrinkage cracks were observed.Initial-oil solid bitumen cracked to oil,gas and post-oil bitumen by primary cracking(R_(o)=0.98%).Moreover,solid bitumen(SB)was found to be the dominant OM when R_(o)>0.98%,which indicates that SB is the product of oil-prone macerals transformation.Many secondary bubble pores were observed on SB,which formed by gas release,while devolatilization cracks developed on migrated SB.Additionally,at the late oil window(Ro?1.16%),migrated SB filled the interparticle pore spaces.With further increase in temperature,the liquid oil underwent secondary cracking into pyrobitumen and gas,and spongy pores developed on the pyrobitumen at higher levels of maturity(Ro=1.43%),which formed when pyrobitumen cracked into gas.Vitrinite and inertinite are stable without any visible pores over the range of maturities,verifying their low petroleum generation potential.In addition,it was concluded that clay minerals could have a catalytic effect on the petroleum generation,which may explain why organicclay mixtures had more abundant pores than single OM particles.However,after R_(o)>0.98%,authigenic minerals occupied the organic pore spaces on the organic-clay mixtures,resulting in fewer pores compared to those observed in samples at the early to peak oil window.
基金supported by the Spanish“Plan Nacional de Investigación Científica,Desarrollo e Innovación Tecnológica,Ministerio de Economía y Competitividad(Instituto de Salud CarlosⅢ)”,Grant FIS PI20-0318 co-financed by“Fondo Europeo de Desarrollo Regional ERDF-FEDER European Union”Grant P18-RT-5059“Plan Andaluz de Investigación,Desarrollo e Innovación(PAIDI 2020),Consejería de Transformación Económica,Industria,Conocimiento y Universidades,Junta de Andalucía,Espana”(all to VC)Grant PPJIA202219“Ayudas del plan propio UGR 2022,Plan propio de investigación y transferencia,Universidad de Granada,Espana”(to JCA andóDGG)。
文摘The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve fibers.Due to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental conditions.Today,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience research.In this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining methods.Considering the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.
基金Cumhuriyet University Scientific Research Project Foundation
文摘AIM:To investigate the side effects of the commonly used laser treatment along with testing the neuroprotective effect of bFGF on a potential retinal impairment.METHODS:To do this,30 chinchilla pigmented adult male rabbits were divided into the control and experimental groups.The control and experimental groups underwent both laser application and bFGF treatment.The retinal tissue impairment and its renewal rate were tested under the light and electron microscopical levels.RESULTS:The focal laser application on rabbit eyes caused morphological alterations both in the application region and in the neighbouring areas.In the damaged areas,the outer nuclear layer of the neural retina was almost disappeared,retina pigment epithelium was interrupted,the retina pigment epithelium migrated intraretinally,and the damaged region along with neighbouring areas seemed to be not separated.bFGF application just after the laser photocoagulation,revealed better results in application areas.CONCLUSION:It could be suggested that the bFGF application following laser photocoagulation might have protective,repairing and wound healing effects on the retina.
文摘In the present study, histopathology of three varieties of sesame TS 3, TS 5 and SG 27 infected with Alternaria alternata was carried out to understand the mechanism of fungal infection and penetration in sesame plant as well as to determine the histological manifestation in sesame cells by light microscopy. Fungus was identified in infected tissues as a dark bluish black with toluidine blue O staining. Light microscopic examination of sesame stem showed that the fungus was present in epidermis, hypodermis and cortical parenchyma tissue as the symptoms became visible by naked eye ten days after inoculation (DAI). As the disease progress, the fungus moved from cortical parenchyma to vascular bundle, xylem and phloem. Later on, it completely overlapped the vascular bundle and entered in pith. When necrotic lesion appeared, fungus was present abundantly in epidermis, hypodermis, cortical parenchyma, vascular bundles and in pith. Due to its excessive growth and complete overlapping of cells, disorganization or destruction of cells of sesame took place. It was concluded that the Alternaria alternata was not a tissue limited pathogen instead of this it spread in to all tissues of stem from epidermis to pith.
文摘Background: Worldwide, diabetic nephropathy-DN is the leading cause of end-stage kidney disease-ESKD, DN is a common cause of renal failure with a reported frequency of 10% - 15% in type-2-diabetes-mellitus-T2DM patients, however there is a great discrepancy between countries. The aim of the pre-sent study is to evaluate the findings of kidney biopsies performed on diabetic patients. Materials and Methods: We studied native kidney histopathological findings in the period from January 2016 till end of December 2018 done for patients with T2DM with chronic kidney diseases-CKD. Results: A total of 82 DM-patients, 50 males (61%) and 32 females (39%) with age mean (95% CI) of 50.8 (47.1 - 55.2) years for all patients, ranged between 15 to 65 years. Histological findings showed that 57.3% of patients had DN. While focal-segmental-glomerulosclerosis-FSGS was present in 20.7%—primary in 8.6% and secondary in 12.1%. IgA represented 4.9%, while Lupus nephritis, Membranous and drug induced interstitial nephritis were each present in 3.7%. MCD was present in 2.4%. Lastly diffuse proliferative GN, ANCA associated glomerulonephritis, and hypertensive nephrosclerosis accounted for 1.2%. Conclusion: The prevalence of NDKD is remarkably frequent in DM patients who underwent kidney biopsy and FSGS was the most frequent diagnosis. To get a proper histopathological diagnosis, an adequate tissue biopsy is needed with an adequate number of glomeruli. There is a great need for more consideration to biopsy diabetic patients, as the finding of NDKD requires a different therapeutic approach. This, hopefully, will help to manage these patients better and therefore, ameliorate the progression to ESKD over time and therefore delay the need for RRT.
