Unraveling the morphological evolution mechanism of solid sulfur species in lithium-sulfur batteries with operando light microscopy

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.

Application of polarized light microscopy on microstructural characterization of semisolid slurry

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.

Quantification of polarization distribution from polarizing light microscopy images of ferroelectric single crystals

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.

Advancing respirable coal mine dust source apportionment:a preliminary laboratory exploration of optical microscopy as a novel monitoring tool

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.

Three-dimensional,isotropic imaging of mouse brain using multi-view deconvolution light sheet microscopy

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.

Single-cell volumetric imaging with light field microscopy: Advances in systems and algorithms

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.

AN ENZYMOCYTOCHEMICAL STUDY OF ALKALINE PHOSPHATASE ISOENZYMES IN GASTRIC CANCER-LIGHT AND ELECTRON MICROSCOPIC OBSERVATIONS

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.

The impact of Electroacupuncture on chronic stress which induced depression rats＇ hippocampal structure and function of AST under light microscope

[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.

Myelin histology:a key tool in nervous system research

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.

A two-step superplastic forging forming of semi-continuously cast AZ70 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.

Protective effect of basic fibroblast growth factor on laser induced retinopathy

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.

Maceral evolution of lacustrine shale and its effects on the development of organic pores during low mature to high mature stage:A case study from the Qingshankou Formation in northern Songliao Basin,northeast China

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.

Stem Histopathology of Sesame Seedlings Infected with Alternaria alternata

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.

Non-Diabetic Kidney Disease in Type 2 Diabetes Mellitus: A Study of 82 Patients and Review of the Literatures

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.

Effects of perinatal protein deprivation and recovery on esophageal myenteric plexus

AIM:To evaluate effects of preand postnatal protein deprivation and postnatal recovery on the myenteric plexus of the rat esophagus. METHODS: Three groups of young Wistar rats (aged 42 d) were studied: normalfed (N42), proteindeprived (D42), and proteinrecovered (R42). The myenteric neurons of their esophagi were evaluated by histochemical reactions for nicotinamide adenine dinucleotide (NADH), nitrergic neurons (NADPH)diaphorase and acetylcholinesterase (AChE), immunohistochemical reaction for vasoactive intestinal polypeptide (VIP), and ultrastructural analysis by transmission electron microscopy.RESULTS: The cytoplasms of large and medium neurons from the N42 and R42 groups were intensely reactive for NADH. Only a few large neurons from the D42 group exhibited this aspect. NADPH detected in the D42 group exhibited low reactivity. The AChE reactivity was diffuse in neurons from the D42 and R42 groups. The density of large and small varicosities detected by immunohistochemical staining of VIP was low in ganglia from the D42 group. In many neurons from the D42 group, the double membrane of the nuclear envelope and the perinuclear cisterna were not detectable. NADH and NADPH histochemistry revealed no group differences in the prof ile of nerve cell perikarya (ranging from 200 to 400 μm2).CONCLUSION: Protein deprivation causes a delay in neuronal maturation but postnatal recovery can almost completely restore the normal morphology of myenteric neurons.

Palyno-Morphological Study of Allergenic Flora of Samarkand, Uzbekistan

This study set out to look into the palyno-morphological characteristics of specific allergenic species from diverse plant families in Samarkand, Uzbekistan. Six different species i.e. Betula pendula, Fraxinus pennsylvanica, Magnolia × soulangeana, Pinus brutia var. eldarica, Populus alba, Quercus robur were collected, pressed, identified, and then examined under a microscope. Under light microscope, both quantitative and qualitative characteristics of the pollen grains were recorded, including pollen type, pollen size, pollen shape (polar and equatorial view), P/E ratio, mesocolpium distance, exine thickness, colpi type, colpi length, and width. It was found that a warm spring in Uzbekistan causes an early commencement of the vegetative and dusting phases, in contrast to the climatic circumstances of the researched entities’ motherland (cold spring). Studies in aeropalinology and morphology enable the resolution of numerous environmental issues. The findings highlighted the importance of pollen morphology as an identifying aid and showed how the tested species’ palynological characteristics varied. In order to promote future phylogenetic description of the Uzbekistan flora, the current study may help us better understand the palynomorphological traits of native plants. This essay only briefly and inadequately addresses these issues. The information gathered will be used to make an atlas of allergic plants in Samarkand and an electronic warning system for the general public about the spread of pollen from the city’s allergenic plants in the future.

Microanatomy of Moina eugeniae （Branchiopoda, Cladocera）

Moina eugeniae is the most abundant species in the southwest lagoons of Buenos Aires province. The aim of this work is to study the histology of this cladoceran by light microscopy so as to expand the knowledge of this species. The parthenogenetic females were fixed in formaldehyde 4%. Sections were cut 3 μm thick and stained with Hematoxylin and Eosin. The intestine has simple cuboidal epithelium with apical projections and the cells have 1 or 2 nucleoli in their nuclei. Two compound eyes were found and no naupliar ocelum. The ovary is saccular and it is presented in a pair at both sides of the intestine with follicles in different states of development. The striated muscle with notorious microfibrills is recognized in antennas, antennules and trunk appendices. This article may represent the first detailed description of the histology of this species.

Possible Relevance of the Allende Meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds

The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic Ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the Mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies.

Application of light sheet microscopy for qualitative and quantitative analysis of bronchus-associated lymphoid tissue in mice

Bronchus-associated lymphoid tissue(BALT)develops at unpredictable locations around lung bronchi following pulmonary inflammation.The formation and composition of BALT have primarily been investigated by immunohistology that,due to the size of the invested organ,is usually restricted to a limited number of histological sections.To assess the entire BALT of the lung,other approaches are urgently needed.Here,we introduce a novel light sheet microscopy-based approach for assessing lymphoid tissue in the lung.Using antibody staining of whole lung lobes and optical clearing by organic solvents,we present a method that allows in-depth visualization of the entire bronchial tree,the lymphatic vasculature and the immune cell composition of the induced BALT.Furthermore,three-dimensional analysis of the entire lung allows the qualitative and quantitative enumeration of the induced BALT.Using this approach,we show that a single intranasal application of the replication-deficient poxvirus MVA induces BALT that constitutes up to 8%of the entire lung volume in mice deficient in CCR7,in contrast to wild type mice(WT).Furthermore,BALT induced by heat-inactivated E.coli is dominated by a pronounced T cell infiltration in Cxcr5-deficient mice,in contrast to WT mice.

Volumetric Imaging of Neural Activity by Light Field Microscopy

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.