Controllable Pseudoelasticity in Metallic Nanocrystals by Grain Boundary Engineering.

Materials with pseudoelasticity can recover from large strains exceeding their elastic limits during unloading, making them promising damage-tolerant building blocks for advanced nanodevices. Nevertheless, a practical approach to realize controllable pseudoelastic behavior at nanoscale remains challenging. Here, we proposed a grain boundary (GB) engineering approach to endow metallic nanocrystals with a controllable pseudoelasticity. Both in situ nanomechanical testing and atomistic simulations demonstrate that such controllable pseudoelasticity is governed by the extension and contraction of an inherent stacking fault array at the GB. By precisely tuning GB misorientation and inclination, our simulation results reveal that metallic nanocrystals can exhibit tailored pseudoelastic performance across a broad spectrum of GBs in different face-centered cubic metals. These findings enrich our understanding of the intrinsic pseudoelasticity of GBs and provide a GB engineering approach toward metallic materials with reversible deformability.

Exploring the antibiofilm and toxicity of tin oxide nanoparticles: Insights from in vitro and in vivo investigations.

BACKGROUND INFORMATION: The advancement of biological-mediated nanoscience towards higher levels and novel benchmarks is readily apparent, owing to the use of non-toxic synthesis processes and the incorporation of various additional benefits. This study aimed to synthesize stable tin oxide nanoparticles (SnO2-NPs) using S. rhizophila as a mediator. METHODS: The nanoparticles that were created by biosynthesis was examined using several analytical techniques, including Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), UV-visible (UV-vis) spectroscopy, and energy dispersive X-ray spectroscopy (EDS). RESULTS: The results obtained from the characterization techniques suggest that S. rhizophila effectively catalyzed the reduction of SnCl2 to SnO2-NPs duration of 90 min at ambient temperature with the ƛmax of 328 nm. The size of the nano crystallite formations was measured to be 23 nm. The present study investigates nanoscale applications' antibacterial efficacy against four bacterial strains, including Klebsiella Sp, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The observed zone of inhibition for the nanoparticles (NPs) varied from 10 to 25 mm. The research findings demonstrate that the nanoparticles (NPs) are effective as antibacterial, phytotoxic, and cytotoxic agents.

Association between hepatitis C virus genotype 4 and renal cell carcinoma: Molecular and virological studies.

Hepatitis C virus (HCV) is the most common infection worldwide. The correlation between HCV and renal cell carcinoma (RCC) is still mysterious. Therefore, the relationship between HCV and RCC was investigated. The study included 100 patients with RCC; 32 with HCV infection, and 68 without HCV infection. Expressions of viral proteins (NS3 and NS5A) were tested using an immune electron-microscope (IEM) and immunohistochemistry (IHC). IHC and quantitative real time-PCR investigated the presentation of human proteins TP53 and p21 genes. Transmission electron (TEM) detected viral-like particles in infected RCC tissues. The gene and protein expression of P53 was higher in HCV positive versus HCV negative patients and p21 was lower in HCV positive versus HCV negative in both tumor and normal tissue samples. Viral like particles were observed by TEM in the infected tumor and normal portion of the RCC tissues and the plasma samples. The IEM showed the depositions of NS3 and NS5A in infected renal tissues, while in noninfected samples, were not observed. The study hypothesizes that a correlation between HCV and RCC could exist through successfully detecting HCV-like particles, HCV proteins, and (p53 and p21) in RCC-infected patients.

Atom-by-Atom Direct Writing.

Direct-write processes enable the alteration or deposition of materials in a continuous, directable, sequential fashion. In this work, we demonstrate an electron beam direct-write process in an aberration-corrected scanning transmission electron microscope. This process has several fundamental differences from conventional electron-beam-induced deposition techniques, where the electron beam dissociates precursor gases into chemically reactive products that bond to a substrate. Here, we use elemental tin (Sn) as a precursor and employ a different mechanism to facilitate deposition. The atomic-sized electron beam is used to generate chemically reactive point defects at desired locations in a graphene substrate. Temperature control of the sample is used to enable the precursor atoms to migrate across the surface and bond to the defect sites, thereby enabling atom-by-atom direct writing.

Effects of eczema calming lotion on the stratum corneum in atopic dermatitis: Corneodesmosin and intercellular lipid lamellae.

OBJECTIVE: Atopic dermatitis (AD) is characterized by compositional and structural changes to the skin at lesional sites. Alteration to the levels and organization of both protein and lipid components are associated with disease status and lead to impaired barrier and hydration. Corneodesmosin (CDSN) and the arrangement and length of the intercellular lipid lamellae (ICLL) are altered in disrupted skin states. The aim of this research was to profile the distribution of CDSN and the ICLL in the stratum corneum (SC) at lesional and non-lesional sites in AD-prone skin and to investigate the impact of an eczema calming lotion containing petroleum jelly, fatty acids, and colloidal oatmeal. METHODS: An IRB-approved study was conducted with participants with active AD. From a small subset of participants, tape strips were collected from lesional and non-lesional sites on the arm, prior to and after twice daily application, over 4 weeks of an eczema calming lotion containing petroleum jelly, fatty acids, and colloidal oatmeal. Fluorescent antibody staining was used to investigate the distribution of CDSN. Transmission electron microscopy (TEM) was used to characterize the ICLL. RESULTS: The distribution/coverage of CDSN was similar between lesional and non-lesional sites at baseline; application of the lotion resulted in a more defined honeycomb/peripheral distribution. Normalized ICLL (nICLL) was lower in baseline samples from lesional sites relative to non-lesional sites. Application of the lotion increased this parameter by the end of the study at all sites. CONCLUSION: The eczema calming lotion containing petroleum jelly, fatty acids and colloidal oatmeal provided changes in corneodesmosomal proteins distribution and ICLL, consistent with improvements in corneocyte maturation and improved barrier function in the skin of individuals with atopic dermatitis.

OBJECTIF: La dermatite atopique (DA) est caractérisée par des modifications de la composition et de la structure de la peau au niveau des sites lésionnels. L'altération des taux et de l'organisation des composants protéiques et lipidiques est associée au statut de la maladie, et entraîne une altération de la barrière et de l'hydratation. La cornéodesmosine (CDSN), et la disposition et la longueur des lamelles lipidiques intercellulaires (LLIC) sont altérées dans les états cutanés perturbés. L'objectif de cette étude était d'établir le profil de la distribution de la CDSN et des LLIC dans la couche cornée (CC) au niveau des sites lésionnels et non lésionnels dans la peau sujette à la DA, et d'étudier l'impact d'une lotion apaisante contre l'eczéma contenant de la vaseline, des acides gras et de l'avoine colloïdale. MÉTHODES: Une étude approuvée par un CPP a été menée auprès de participants atteints de DA active. Dans un petit sous­ensemble de participants, des bandes adhésives ont été prélevées sur des sites lésionnels et non lésionnels du bras, avant et après l'application deux fois par jour pendant 4 semaines d'une lotion apaisante contre l'eczéma contenant de la vaseline, des acides gras et de l'avoine colloïdale. Une coloration par anticorps fluorescents a été utilisée pour étudier la distribution de la CDSN. La microscopie électronique en transmission (MET) a été utilisée pour caractériser les LLIC. RÉSULTATS: La distribution/couverture de la CDSN était similaire entre les sites lésionnels et non lésionnels à l'entrée dans l'étude; l'application de la lotion a entraîné une distribution en nid d'abeille/périphérique plus définie. Le taux normalisé de LLIC (LLICn) était plus faible dans les échantillons prélevés à l'entrée dans l'étude au niveau des sites lésionnels par rapport aux sites non lésionnels. L'application de la lotion a augmenté ce paramètre à la fin de l'étude pour tous les sites. CONCLUSIONS: La lotion apaisante contre l'eczéma contenant de la vaseline, des acides gras et de l'avoine colloïdale a entraîné des changements dans la distribution des protéines cornéodesmosomales et des LLIC, ce qui correspond à des améliorations de la maturation des cornéocytes et de la fonction de barrière de la peau des personnes atteintes de dermatite atopique.

Transmission electron microscopic study of the surface layer of surgical resected disc specimens in human temporomandibular joint.

In this study, we investigated specific and characteristic findings of the surface layer of surgical resected disc specimens in human temporomandibular joint osteoarthritis cases by transmission electron microscopy (TEM).Specimens were surgically removed from the TMJ of 5 cases (4 female patients: 5 cases) clinically osteoarthritis. Following findings were observed by TEM. Images were photographed on a JEM1400-Flash Electron microscope (JEOL, Japan) equipped with an EM-14661FLASH high-sensitivity digital complementary metal-oxide-semiconductor camera.Following findings were observed by TEM. 1) The surface is covered with plump fibroblastic and histiocytoid cells. 2) Collagen fiber bundles and collagenous matrix are exposed onto the eroded disc surface. 3) Fibrinous dense material is observed on the eroded disc surface. 4) Bundles of collagen fibers are densely observed. 5) Collagen bundles are rich around capillary vessels. 6) Synovial surface cells reveal features of activated macrophages with vacuole formation. Especially, plump fibroblastic and histiocytoid cells, and activated macrophages with vacuole, which were significant findings of the surface layer. These findings might have a significant effect on the regulation of synovial fluid.

Research on the damage and wound repair of cornea by GO and ZnO.

OBJECTIVE: The widespread use of nanoparticles in recent years has increased the risk of ocular exposure. zinc oxide (ZnO) is widely used in the field of cosmetics because of its unique chemical properties. The application of graphene oxide (GO) as an emerging nanomaterial in the field of eye drops is also gradually emerging. Currently, research on ZnO and GO eye exposure mainly focuses on application or toxicity to optic nerve cells. There's less study on corneal wound healing effects. and the previous research hasn't compared ZnO and GO corneal toxicity. METHODS: We systematically established a complete chain study of in vitro and in vivo experiments and mouse corneal injury model, and comprehensively evaluated the ocular safety and toxicity of ZnO and GO. RESULTS: We found that 50 ug/mL GO and 0.5 ug/mL ZnO can reduce human corneal epithelial cells (HCEpiC) viability in a concentration-dependent manner. Short-term repeated exposure to ZnO can cause sterile inflammation of the cornea with concentration-dependence, while GO have not been significantly altered. 50 ug/mL ZnO could significantly delay the healing of corneal wounds, while GO did not change wound healing. CONCLUSION: The toxic effect of ZnO is higher than that of GO. Inflammatory signal transduction, oxidative stress and apopnano zitosis are involved in the ocular toxicity injury process of nanoparticles. Research can provide a judgement basis for people's eye health and eye protection risk control.

Rapidly Constructing Sodium Fluoride-Rich Interface by Pressure and Diglyme-Induced Defluorination Reaction for Stable Sodium Metal Anode.

Sodium (Na) metal is able to directly use as a battery anode but have a highly reductive ability of unavoidably occurring side reactions with organic electrolytes, resulting in interfacial instability as a primary factor in performance decay. Therefore, building stable Na metal anode is of utmost significance for both identifying the electrochemical performance of laboratory half-cells employed for quantifying samples and securing the success of room-temperature Na metal batteries. In this work, we propose an NaF-rich interface rapidly prepared by pressure and diglyme-induced defluorination reaction for stable Na metal anode. Once the electrolyte is dropped into the coin-type cells followed by a slight squeeze, the Na metal surface immediately forms a protective layer consisting of amorphous carbon and NaF, effectively inhibiting the dendrite growth and dead Na. The resultant Na metal anode exhibits a long-term cycling lifespan over 1800 h even under the area capacity of 3.0 mAh cm-2 . Furthermore, such a universal and facile method is readily applied in daily battery assembly regarding Na metal anode.

Dynamic Observation of the Coulomb Explosion and Field Evaporation of a Few-Layer Graphene Nanoribbon.

The Coulomb explosion and field evaporation are frequently observed physical phenomena for a metallic tip under an external electric field, which can modify the structures of the tip and have broad applications, such as in the atomic-probe tomography and field ion microscopy. However, the mechanistic comprehending of how they change the structures of the tip and the differences between them are not clear. Here, dynamic observations of Coulomb explosions and field evaporations on the positively biased and charged few-layer graphene (FLG) nanoribbon inside a transmission electron microscope are reported. By combining the atomic-scale molecular dynamic simulations, it is shown that the FLG is split into several sheets under Coulomb explosion. It is also observed to break by emitting the carbon ions/segments under the field evaporation. It is further demonstrated that the split and breaking of FLG can be tuned by the shape of the nanoribbon. FLG ribbons with sharp tips have splitting and breaking occur in sequence. FLG with blunt tips break without a split. These results provide a fundamental understanding of Coulomb explosion and field evaporation in graphene nanomaterials and suggest potential methods to engineer graphene-based nanostructures.

Antibacterial and anti-corona virus (229E) activity of Nigella sativa oil combined with photodynamic therapy based on methylene blue in wound infection: in vitro and in vivo study.

Microbial skin infections, antibiotic resistance, and poor wound healing are major problems, and new treatments are needed. Our study targeted solving this problem with Nigella sativa (NS) oil and photodynamic therapy based on methylene blue (MB-PDT). Antibacterial activity and minimum inhibitory concentration (MIC) were determined via agar well diffusion assay and broth microdilution, respectively. Transmission electron microscopy (TEM) proved deformations in Staphylococcus aureus ATCC 6538. Gas chromatography-mass spectrometry identified useful compounds that were suggested to be responsible for the potency of the oil. NS oil was tested as an antivirus against low pathogenic coronavirus (229E). Therapies examined, MB-PDT, NS, and MB-PDT + NS oil, to accelerate wound healing. The antibacterial efficacy against S. aureus was promising, with a MIC of 12.5% and TEM showing injured cells treated with NS oil. This oil inhibited 229E virus up to 42.85% and 32.14%. All tested therapies were successful in accelerating wound healing. The most successful was combined therapy (MB-PDT + NS oil), with a faster healing time. The combined therapy (MB-PDT + NS oil) reduced bacterial counts, which may be a key factor in accelerating wound healing. Skin wound histology was investigated; blood hematology and biochemical analysis did not change significantly after the safe combination treatment. A combination treatment could facilitate healing in a simple and inexpensive way in the future. Based on the results of the in vitro and in vivo studies, it was determined that NS oil had antibacterial and anti-corona virus activity when used in conjunction with photodynamic treatment based on methylene blue to treat wound infections.

Hybrid tungsten-carbon 2D nanostructures viain situgasification of carbon substrates driven by ebeam irradiation of WO2.9microparticles.

Since the transmission electron microscope (TEM) has the capacity to observe the atomic structure of materials,in situTEM synthesis methods are uniquely suited to advance our fundamental understanding of the bottom-up dynamics that drive the formation of nanostructures. E-beam induced fragmentation (potentially identified as a manifestation of Coulomb explosion) and electron stimulated desorption are phenomena that have received attention because they trigger chemical and physical reactions that can lead to the production of various nanostructures. Here we report a simple TEM protocol implemented on WO2.9microparticles supported on thin amorphous carbon substrates. The method produces various nanostructures such as WC nanoparticles, WC supported films and others. Nevertheless, we focus on the gradual graphitization and gasification of the C substrate as it interacts with the material expelled from the WO2.9microparticles. The progressive gasification transforms the substrate from amorphous C down to hybrid graphitic nanoribbons incorporating W nanoparticles. We think these observations open interesting possibilities for the synthesis of 2D nanomaterials in the TEM.

Buckling and fracture characterization of pristine bundles of vertically aligned carbon nanotubes using quantitativein situTEM axial compression.

This work investigates the mechanical deformation and fracture characteristics of pristine bundles of vertically aligned multi-walled carbon nanotubes (MWCNTs) subjected to axial compressionin situtransmission electron microscope (TEM). Accurate measurements of force-displacement data were collected simultaneously with real-time TEM videos of the deformation process. Two distinct regimes were observed in the force-displacement curve: (1) an initial elastic section with a linear slope, followed by (2) a transition to a force plateau at a critical buckling force. Morphological data revealed coordinated buckling of the pristine bundle, indicating strong van der Waals (VdW) forces between the nanotubes. The experimental setup measured an effective modulus of 83.9 GPa for an MWCNT bundle, which was in agreement with finite element analysis (FEA) simulations. FEA also highlighted the significant role of VdW forces in the bundle mechanical reactions. Furthermore, we identified nickel nanoparticles as key players in the fracture behavior of the bundles, acting as nucleation sites for defects. The direct mechanical measurements of MWCNT bundles provide valuable insights into their mechanical deformation and fracture behavior, while correlating it to the morphology of the bundle. Understanding these interactions at the bundle level is crucial for improving the reliability and durability of VACNTs-based components.

Growth of quasi-1 dimensional (Bi1-xSbx)2S3nanowires on fluorine-doped tin oxide glass substrate by vapor transport.

(Bi1-xSbx)2S3solid solution nanowires (0≤x≤0.73) are grown on fluorine-doped tin oxide (FTO) glass via physical vapor transport. The compositions were controlled by varying the Sb2S3source temperature (300 °C-453 °C) by changing the upstream locations of the Sb2S3source in the furnace while keeping the Bi2S3source at the center of the furnace (497 °C). Defect-free nanowires with phase-pure orthorhombic and quasi-1 dimensional crystal structures were grown under a modified vapor-solid mechanism affected by FTO at initial growth stage. The aspect ratios of the nanowires reached the minimum at compositionx∼0.6.As the Sb2S3source approached the Bi2S3source,xincreased owing to the increase in the Sb2S3source temperature.x/(1-x), which is proportional to the evaporation flux of the Sb2S3source, could be well-fitted with a thermally activated equation with an apparent activation energy (105kJmol-1). However, at the distance between the Sb2S3and Bi2S3sources, with the Sb2S3source at temperatures higher than 410 °C, the compositions reduced despite the increased Sb2S3evaporation flux. Such retrograde behavior was confirmed by high-resolution transmission electron microscopy, x-ray diffraction, and micro-Raman studies. This retrograde behavior is ascribed to the loss due to the reaction of gaseous Sb species with the Bi2S3source.

Characterization of Anomalous Grains in FeCo Magnetic Alloys.

Heat-treated FeCo-based magnetic alloys were characterized using a suite of electron microscopy techniques to gain insight into their structural properties. Electron channeling contrast imaging (ECCI) in the scanning electron microscope (SEM) found unique grains towards the outer edge of a FeCo sample with nonuniform background contrast. High-magnification ECCI imaging of these nonuniform grains revealed a weblike network of defects that were not observed in standard uniform background contrast grains. High-resolution electron backscattered diffraction (HR-EBSD) confirmed these defect structures to be dislocation networks and additionally found subgrain boundaries within the nonuniform contrast grains. The defect content within these grains suggests that they are unrecrystallized grains, and ECCI can be used as a rapid method to quantify unrecrystallized grains. To demonstrate the insight that can be garnered via ECCI on these unique grains, the sample was imaged before and after micro indentation. This experiment showed that slip bands propagate throughout the material until interacting with the dislocation networks, suggesting that these specific defects provide a barrier to plastic deformation. Taken together, these results show how ECCI can be used to better understand failure mechanisms in alloys and provides further evidence that dislocation networks play a critical role in the brittle failure of FeCo alloys.

Investigation of the Efficacy of Lanthanoid Heavy Metal Acetates as Electron Staining Reagents for Biomembrane Vesicles.

Transmission electron microscopy (TEM) has revolutionized our understanding of protein structures by enabling atomic-resolution visualization without the need for crystallography, thanks to advancements in cryo-TEM and single particle analysis methods. However, conventional electron microscopy remains relevant for studying stained samples, as it allows the practical determination of optimal conditions through extensive experimentation. TEM also facilitates the examination of supramolecular complexes encompassing proteins, lipids, and nucleic acids. In this study, we investigated the applicability of lanthanoid reagents as electron-staining alternatives to uranyl acetate, which is globally regulated as a nuclear fuel material. We focus on a model biomembrane vesicle system, the chromatophores from the purple photosynthetic eubacterium Rhodospirillum rubrum, which integrate proteins and lipids. Through density distribution analysis of electron micrographs, we evaluated the efficacy of various lanthanoid acetates and found that triacetates of neodymium, samarium, and gadolinium exhibited similar staining effectiveness to uranyl acetate. Additionally, triacetates of praseodymium, erbium, and lutetium, followed by europium show promising results as secondary candidates. Our findings suggest that lanthanoid transition heavy metal acetates could serve as viable alternatives for electron staining in TEM, offering potential advantages over uranyl acetate.

Synthesis and insecticidal activities of 4-(propargyloxy) benzenesulfonamide derivatives.

A series of 4-(propargyloxy) benzenesulfonamide derivatives with different substituents on the benzene ring were synthesized and evaluated for their insecticidal activity. Some of the compounds showed good insecticidal activity against Mythimna separata, and the LC50 value of the most active compound B2.5 was 0.235 mg/ml. Ultrastructural changes in the midgut epithelial cells of Mythimna separata were observed using transmission electron microscopy, and severe structural damage was found in microvilli, mitochondria and rough endoplasmic reticulum. It indicates that the possible site of action of these benzenesulfonamides is the cytoplasmic membrane and endomembrane system of the midgut epithelial cells. The above provides a basis for the development of novel insecticidal active compounds with a novel mechanism of action.

Severe Acute Liver Dysfunction Induces Delayed Hepatocyte Swelling and Cytoplasmic Vacuolization, and Delayed Cortical Neuronal Cell Death.

Liver dysfunction is the main cause of hepatic encephalopathy. However, histopathological changes in the brain associated with hepatic encephalopathy remain unclear. Therefore, we investigated pathological changes in the liver and brain using an acute hepatic encephalopathy mouse model. After administering ammonium acetate, a transient increase in the blood ammonia level was observed, which returned to normal levels after 24 h. Consciousness and motor levels also returned to normal. It was revealed that hepatocyte swelling, and cytoplasmic vacuolization progressed over time in the liver tissue. Blood biochemistry also suggested hepatocyte dysfunction. In the brain, histopathological changes, such as perivascular astrocyte swelling, were observed 3 h after ammonium acetate administration. Abnormalities in neuronal organelles, especially mitochondria and rough endoplasmic reticulum, were also observed. Additionally, neuronal cell death was observed 24 h post-ammonia treatment when blood ammonia levels had returned to normal. Activation of reactive microglia and increased expression of inducible nitric oxide synthase (iNOS) were also observed seven days after a transient increase in blood ammonia. These results suggest that delayed neuronal atrophy could be iNOS-mediated cell death due to activation of reactive microglia. The findings also suggest that severe acute hepatic encephalopathy causes continued delayed brain cytotoxicity even after consciousness recovery.

Pathological analysis of lesions in the exocrine pancreas of rats induced by Zinc Maltol.

The pancreas plays an important role in the homeostasis of zinc (Zn), a nutritionally essential metal. In several previous studies, Zn ions induced inflammatory changes in the exocrine pancreas; however, little is known about Zn complexes. In this study, we microscopically, immunohistochemically, and ultrastructurally examined pancreatic lesions in Sprague-Dawley (SD) rats induced by a 4-week repeated oral dose toxicity study of Zinc Maltol (ZM), a zinc (II) complex. ZM induces acinar atrophy and increases the number of duct-like structures. Immunohistochemistry revealed a decrease in the number of trypsin-positive cells, and an increase in the number of SOX9-positive cells. Interstitial fibrosis and macrophage infiltration also correlated with the degree of acinar atrophy. Electron microscopic evaluation revealed that the acinar cells that lost granules were surrounded by fibroblasts and collagen fibers. In conclusion, we provided a detailed description of ZM-induced pancreatic lesions in SD rats.

High-quality, large-scale, semi-thin, & ultra-thin sections of the optic nerve in large animals: An optimized procedure.

Large animal model of optic nerve (ON) injury is an essential tool for translational medicine. Perfusion fixation with paraformaldehyde is mainly used for preparing the semi-thin (1-2 µm thick) and ultra-thin (<0.5 µm thick) sections of the ON tissues. However, this conventional fixation technique in large animals needs a large volume of fixatives, which increases the risk of toxic exposure and is environmentally unfriendly. Additionally, fixed residual ON cannot be used for other tests that require fresh tissue samples. Although conventional immersion fixation is feasible for preparing a semi-thin section of the ON in small animals (0.2-0.6 mm in diameter), it faces technical challenges when fixing the ON of large animals (3 mm in diameters), as increased diameter limits the permeability of the fixatives into deeper tissue. Therefore, we optimized the immersion-fixation method to obtain high-quality, large-scale, semi-thin, and ultra-thin sections for the ON of goat and rhesus macaques. Using this optimized technique, the ON microstructure was well preserved throughout the entire area of 1.5*1.5 square millimeters, allowing confident quantification of axon density/diameter on semi-thin section and identification of specific organelles and glial cells on ultra-thin sections. Furthermore, the optimized technique is a quick, simple, and environmentally friendly fixation method. Notably, the ON regions of large animals with or without an intact neurovascular system can be prepared for light and electron microscopy. In contrast, the residual unfixed ON from the same animal can be further utilized for experiments such as tissue culture and biomolecular tests.

Electron-beam induced damage process for Ca2Na2Nb5O16nanosheets.

Dielectric two-dimensional oxide nanosheets are attractive because of their thermal stability and high-k property. However, their atomic structure characterization has been limited since they are easily degraded by electron-beams. This study aimed to investigate the electron-beam induced damage mechanisms for exfoliated Ca2Na2Nb5O16(CNNO) nanosheets. Knock-on damage dominantly occurred at high voltages, leaving short-range order in the final amorphous structure. On the other hand, a series of chemical reactions predominantly occurred at low voltages, resulting in random elemental loss and a fully disordered amorphous structure. This radiolysis was facilitated by insulated CNNO nanosheets that contained a large number of dangling bonds after the chemical solution process. The radiolysis damage kinetics was faster than knock-on damage and induced more elemental loss. Based on our understanding of the electron beam-induced degradation, atomic-scale imaging of the CNNO nanosheets was successfully performed using Cs-corrected scanning transmission electron microscopy at 300 keV with a decreased beam current. This result is of particular significance because understanding of electron-beam damage in exfoliated and insulating 2D oxide sheets could improve identification of their atomic structure using electron microscopy techniques and lead to a practical guide for further extensive characterization of doped elements and layered structures to improve their properties.