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Over the last two decades, Electron Energy Loss Spectroscopy (EELS) imaging with a scanning transmission electron microscope has emerged as a technique of choice for visualizing complex chemical, electronic, plasmonic, and phononic phenomena in complex materials and structures. The availability of the EELS data necessitates the development of methods to analyze multidimensional data sets with complex spatial and energy structures. Traditionally, the analysis of these data sets has been based on analysis of individual spectra, one at a time, whereas the spatial structure and correlations between individual spatial pixels containing the relevant information of the physics of underpinning processes have generally been ignored and analyzed only via the visualization as 2D maps. Here, we develop a machine learning-based approach and workflows for the analysis of spatial structures in 3D EELS data sets using a combination of dimensionality reduction and multichannel rotationally invariant variational autoencoders. This approach is illustrated for the analysis of both the plasmonic phenomena in a system of nanowires and in the core excitations in functional oxides using low loss and core-loss EELS, respectively. The code developed in this manuscript is open sourced and freely available and provided as a Jupyter notebook for the interested reader. [ABSTRACT FROM AUTHOR]

Low-energy ion beam irradiation, combined with the introduction of impurities, presents a promising approach for nanopatterning silicon (Si) surfaces. In this research, we investigate the surface evolution of Si (100) surfaces irradiated by 75 eV helium (He) plasma, in the presence of tantalum (Ta), traditionally regarded as an impurity incapable of initiating pattern formation, as evidenced in prior studies. The Ta impurities are pre-deposited onto the Si surfaces using the magnetron sputtering method, which offers a more controlled and quantifiable approach compared with the conventional co-deposition route. After irradiation at 800 K, dense cone arrays are produced on the Si surface. The growth of the cones is explored for fluence spanning (1–10) × 1025 m−2. The cross-sectional scanning electron microscope images indicate that the cone lengths and base width are well characterized by t1/2 dependence. The kinetics of the cone growth follow Fick's law, characterized by an effective diffusive mechanism with the coefficients of diffusion: D = 6.49 ± 0.83 × 10−16 m−2 s−1. Transmission electron microscope observations reveal that the cone has distinct inner and outer parts with different microstructures and a clear interface. The growth mechanism of these cones is elucidated as a composite process involving preferential sputtering, the destabilizing influence of He bubbles, and the migration of adatoms. [ABSTRACT FROM AUTHOR]

Epitaxial growth of wurtzite AlN films on Si {111} results in 19% lattice misfit, which gives rise to a large density of threading dislocations with different recombination rates of electron–hole pairs. Here, we investigate types and distributions of threading dislocations of the MOVPE-grown 200 nm AlN/Si {111} film, whereby the dislocations are visualized using the technique of wet chemical etching. Atomic force microscopy suggests the existence of four different types of etch pits without any topological differences. Cross-sectional transmission electron microscope studies on etched samples are employed to associate the types of dislocations with the shapes of their etch pits. The recombination activity of individual dislocations was quantified by measuring the electron beam induced current and by correlative measurement of topography, secondary electron imaging, and the electron beam absorbed current. The strongest recombination activity was obtained for the m + c-type (mixed), c-type (screw), and a + c-type (mixed) threading dislocations, whereas the a-type (edge) threading dislocations were nearly recombination-inactive. [ABSTRACT FROM AUTHOR]

Electron energy-loss spectroscopy (EELS) can measure similar information to x-ray, UV–Vis, and IR spectroscopies but with atomic resolution and increased scattering cross-sections. Recent advances in electron monochromators have expanded EELS capabilities from chemical identification to the realms of synchrotron-level core-loss measurements and to low-loss, 10–100 meV excitations, such as phonons, excitons, and valence structures. EELS measurements are easily correlated with electron diffraction and atomic-scale real-space imaging in a transmission electron microscope (TEM) to provide detailed local pictures of quasiparticle and bonding states. This perspective provides an overview of existing high-resolution EELS (HR-EELS) capabilities while also motivating the powerful next step in the field—ultrafast EELS in a TEM. Ultrafast EELS aims to combine atomic-level, element-specific, and correlated temporal measurements to better understand spatially specific excited-state phenomena. Ultrafast EELS measurements also add to the abilities of steady-state HR-EELS by being able to image the electromagnetic field and use electrons to excite photon-forbidden and momentum-specific transitions. We discuss the technical challenges ultrafast HR-EELS currently faces, as well as how integration with in situ and cryo measurements could expand the technique to new systems of interest, especially molecular and biological samples. [ABSTRACT FROM AUTHOR]

Site- and polarity-controlled core–shell InGaN/GaN nanorod LED structures were grown by metal organic vapor phase epitaxy on Si(111). Scanning transmission electron microscope images reveal uniform multiple quantum wells on polarization-free sidewalls. Spatially resolved photoluminescence mapping on a single nanorod demonstrates that the emission at 3.0 eV stems from the polarization-free m-plane, which is supported by a fast recombination lifetime of ∼490 ps at low temperatures. Quasi-resonant laser excitation demonstrates predominant radiative recombination at low excitation densities, whereas at high excitation densities, the efficiency is lowered by Auger recombination and/or carrier leakage. [ABSTRACT FROM AUTHOR]

TaAs single crystals were grown by a standard chemical vapor transport method. The single-crystallinity and homogeneous distribution of elements were confirmed by transmission electron microscope and x-ray diffraction observations. Positron annihilation measurements revealed that the atomic vacancy concentration was kept below 10 − 5 at. %. However, inductively coupled plasma analysis showed an As-deficient (7–9 at. %) off-stoichiometry. First-principles calculations implied that the off-stoichiometry could be compensated for with excess Ta antisite defects, thereby inducing metallic states. Nevertheless, excellent semimetallic transport properties of a well-suppressed carrier density (≲ 10 18 cm − 3 ), ultrahigh carrier mobility (≳ 10 6 cm 2 /V/s), and large transverse magnetoresistance (> --> 200 000 % at 9 T) with the quantum oscillation were obtained at 1.7 K. This indicated the robustness of semimetallic transport properties against the off-stoichiometric disorder and the quenching of metallic conduction associated with excess Ta atoms. The negative longitudinal magnetoresistance, which is considered evidence of a Weyl semimetal (chiral anomaly), was not observed. These data were discussed with theoretical calculations. [ABSTRACT FROM AUTHOR]

Transmission electron microscope image and electronic transport of La0.7Sr0.3MnO3 (LSMO) films grown on (001) oriented Si using the sputtered pulsed plasma method confirmed the presence of around 8 nm thick, less dense, and highly resistive LSMO at the interface below the conducting phase. Thicker LSMO films, in addition to metal-insulator transition, show an anomaly around the Curie temperature in temperature-dependent resistivity and magnetoresistance (MR), which is a unique observation. The conduction in these LSMO films at temperatures below low-temperature resistivity minimum is dominated by Kondo-like scattering over electron–electron scattering, established using the phenomenological model. At 20 K, the maximum positive MR is ∼ 12% for the in-plane field, while it is ∼ 7.2% for the out-of-plane field. The maximum negative in-plane MR is found to be ∼ 42.5%, which becomes ∼ 30% when the orientation of the field changes to the out-of-plane direction. The two-dimensional field-dependent change in the magneto-conductance model evidenced the quantum interference effect (QIE). The existence of QIE is associated with magnetic scattering and scattering due to spin–orbit coupling. These results may be used to modulate the electrical properties of future electronic devices and can encourage scientists to explore the multi-functionalities of complex oxides grown on bare Si substrates. [ABSTRACT FROM AUTHOR]

Chalcogenide thin films that undergo reversible phase changes show promise for use in next-generation nanophotonics, microelectronics, and other emerging technologies. One of the many studied compounds, Ge2Sb2Te5, has demonstrated several useful properties and performance characteristics. However, the efficacy of benchmark Ge2Sb2Te5 is restricted by amorphous phase thermal stability below ∼150 °C, limiting its potential use in high-temperature applications. In response, previous studies have added a fourth species (e.g., C) to sputter-deposited Ge2Sb2Te5, demonstrating improved thermal stability. Our current research confirms reported thermal stability enhancements and assesses the effects of carbon on crystalline phase radiation response. Through in situ transmission electron microscope irradiation studies, we examine the effect of C addition on the amorphization behavior of initially cubic and trigonal polycrystalline films irradiated using 2.8 MeV Au to various doses up to 1 × 1015 cm−2. It was found that increased C content reduces radiation tolerance of both cubic and trigonal phases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Due to the sudden release and the rapid removal by proteases, platelet-rich plasma hydrogel leads to shorter residence times of growth factors at the wound site. In recent years, researchers have focused on the use of hydrogels to encapsulate platelet-rich plasma in order to improve the deficiency of platelet-rich plasma hydrogels. OBJECTIVE: To prepare self-assembled polypeptide-platelet-rich plasma hydrogel and to explore its effects on the release of bioactive factors of platelet-rich plasma. METHODS: The self-assembled polypeptide was synthesized by the solid-phase synthesis method, and the solution was prepared by D-PBS. Hydrogels were prepared by mixing different volumes of polypeptide solutions with platelet-rich plasma and calcium chloride/thrombin solutions, so that the final mass fraction of polypeptides in the system was 0.1%, 0.3%, and 0.5%, respectively. The hydrogel state was observed, and the release of growth factors in platelet-rich plasma was detected in vitro. The polypeptide self-assembly was stimulated by mixing 1% polypeptide solution with 1% human serum albumin solution, so that the final mass fraction of the polypeptide was 0.1%, 0.3%, and 0.5%, respectively. The flow state of the liquid was observed, and the rheological mechanical properties of the self-assembled polypeptide were tested. The microstructure of polypeptide (mass fraction of 0.1% and 0.001%) -human serum albumin solution was observed by scanning electron microscope and transmission electron microscope. RESULTS AND CONCLUSION: (1) Hydrogels could be formed between different volumes of polypeptide solution and platelet-rich plasma. Compared with platelet-rich plasma hydrogels, 0.1% and 0.3% polypeptide-platelet-rich plasma hydrogels could alleviate the sudden release of epidermal growth factor and vascular endothelial growth factor, and extend the release time to 48 hours. (2) After the addition of human serum albumin, the 0.1% polypeptide group still exhibited a flowing liquid, the 0.3% polypeptide group was semi-liquid, and the 0.5% polypeptide group stimulated self-assembly to form hydrogel. It was determined that human serum albumin in platelet-rich plasma could stimulate the self-assembly of polypeptides. With the increase of the mass fraction of the polypeptide, the higher the storage modulus of the self-assembled polypeptide, the easier it was to form glue. (3) Transmission electron microscopy exhibited that the polypeptide nanofibers were short and disordered before the addition of human serum albumin. After the addition of human serum albumin, the polypeptide nanofibers became significantly longer and cross-linked into bundles, forming a dense fiber network structure. Under a scanning electron microscope, the polypeptides displayed a disordered lamellar structure before adding human serum albumin. After the addition of human serum albumin, the polypeptides self-assembled into cross-linked and densely arranged porous structures. (4) In conclusion, the novel polypeptide can self-assemble triggered by platelet-rich plasma and the self-assembly effect can be accurately adjusted according to the ratio of human serum albumin to polypeptide. This polypeptide has a sustained release effect on the growth factors of platelet-rich plasma, which can be used as a new biomaterial for tissue repair. [ABSTRACT FROM AUTHOR]

BACKGROUND: Clinical studies have found good analgesic effects of silver needle-thermal conduction therapy in patients with myofascial pain syndrome, but the exact mechanism remains unclear. OBJECTIVE: To observe the effect of silver needle-thermal conduction therapy on silent information regulator homolog 3 (SIRT3) changes and mitochondrial ultrastructure in a rat model of myofascial pain syndrome. METHODS: Twenty rats were randomly selected from 26 Sprague-Dawley rats and were subjected to percussion combined with motor fatigue for replicating the rat model of myofascial pain syndrome. Sixteen rats that were successfully modeled were randomly divided into model group and silver needle-thermal conduction therapy group (treatment group), with eight rats in each group. The remaining rats were used as controls (normal group). The treatment group was treated with silver needle-thermal conduction therapy. Mechanical withdrawal threshold and thermal withdrawal latency of rats were measured at 1 day before modeling, 1 day after modeling and 14 days after treatment. Electromyographic activities of the right medial femoral muscle were measured at 14 days after treatment. The right medial femoral muscle tissue was taken for hematoxylin-eosin staining to observe the local morphology and for transmission electron microscopy to observe the mitochondrial ultrastructure. Western blot assay was performed to detect SIRT3 expression. RESULTS AND CONCLUSION: Pain threshold: The mechanical withdrawal threshold and thermal withdrawal latency of the model and treatment groups were significantly decreased compared with those in the normal group and before modeling (P < 0.01). After treatment, the mechanical withdrawal threshold and thermal withdrawal latency of rats were significantly higher in the treatment group compared with the model group (P < 0.01). Electromyography: The rats in the model group showed spontaneous electrical activity in the right medial femur, while the rats in the treatment group showed reduced spontaneous electrical activity, longer time frame (P < 0.01) and lower wave amplitude (P < 0.05) compared with the model group. Hematoxylin-eosin staining: In the normal group, rat muscle fibers arranged closely and regularly. In the model group, the muscle fibers of rats were atrophied, degenerated, and disordered in arrangement. In the treatment group, rat muscle structure disorder improved. Mitochondrial microstructure: Under the transmission electron microscope, mitochondrial structure in the normal group was normal; mitochondrial swelling with broken or disappeared cristae appeared in the model group; mitochondrial swelling in the treatment group was obviously relieved or tended to be normal. SIRT3 expression: SIRT3 expression was significantly downregulated in the model group compared with the normal group, but was significantly upregulated in the treatment group compared with the model group (P < 0.05). To conclude, abnormalities in local muscle mitochondria and downregulation of SIRT3 expression suggest the presence of impaired energy metabolism in the rat model of myofascial pain syndrome. Mitochondrial changes recover and are close to normal after the silver needle-thermal conduction therapy, and the expression of SIRT3 is also upregulated close to the normal group, indicating the silver needle-thermal conduction therapy may play a therapeutic role by promoting mitochondrial repair and improving energy metabolism disorder. [ABSTRACT FROM AUTHOR]

A nanostructure of lithium-zinc copper ferrite (LiZnCu-Ferrite) prepared experimentally by the auto-combustion method depends on different parameters. The auto-combustion method operates at a temperature (160 °C) suitable for preparing the required nanostructure ferrite phase. The dependent composition was [Li 0.5-x Zn x Cu x Fe 2.5-x O 4 at (x = 0, 0.05, 0.15, 0.25, 0.35, and 0.45)]. A pre-firing at temperature (650 °C) was applied during the calcination process that was suitable to remove unwanted products. The sintering at temperature (800 °C) was suitable for a pelletized shape of ferrite samples. The X-ray diffraction (XRD) pattern showed a spinel structure of ferrite phase produced for all samples under study with the lattice constant in the range (8.345–8.368 Å) as a function of (x). The crystallite size was in the range (18.41–30.27 nm) calculated by the Scherrer method. The transmission electron microscope (TEM) showed a production of nanorods in the size range (10–45 nm) and nanoparticles in the size range (10–40 nm). There was a coincidence between the results of the XRD and TEM analyses. On the other hand, the scanning electron microscope (SEM) showed the surface morphology and the nature of grain size, which was a sign of the presence of nanostructure; it agreed with the XRD analysis. FTIR spectra showed evidence that the system Li0.5-xZnxCuxFe2.5-xO4 had spinal ferrite nanoparticles successfully prepared by sol-gel auto-combustion. A vibrating sample magnetometer (VSM) showed a change in magnetic parameters as compensation factor (x) increased for all composites of LiZnCu-ferrite such as saturation magnetization (Ms), initial magnetic permeability (μi), remanence (Mr), and coercive force (Hc) that measured from M − H loops. A saturation magnetization increased as a function of (x) and recorded a maximum value at (x = 0.15). While the coercivity, initial magnetic permeability (μi), and remanence magnetization enhanced as a function of (x) and recorded a maximum value at (x = 0.45). [ABSTRACT FROM AUTHOR]

The layered perovskite Ca 1- x Ba x La 4 Ti 5 O 17 (x = 0.2, 0.4, 0.6, 0.8) compounds were synthesized via the solid-state reaction method, and their phase composition, microstructure and microwave dielectric properties were investigated. X-ray diffraction (XRD), Raman spectroscopy and selected area electron diffraction (SAED) patterns confirmed that it appears as a single phase with orthorhombic perovskite structure belonging to the Pnnm space group when x = 0.2. The crystal structure analysis and high-resolution transmission electron microscope (HRTEM) results showed that the compound has a layered structure composed of 5 unit [TiO 6 ] layers tightly packed (A n B n O 3 n +2 , n = 5). The Q×f value of ceramics was gradually improved with the increase of Ba2+ content, which was attributed to the production of the second phase BaLa 2 Ti 3 O 10 , but it also caused the deviation of the temperature coefficient of resonant frequency (τ f). For the ceramic specimen of x = 0.2, excellent microwave dielectric properties were obtained with an optimal combination (ε r = 57.2, Q×f = 12,100 GHz, and τ f = 0.67 ppm/°C). Ba-modified CaLa 4 Ti 5 O 17 ceramics with comprehensive and excellent performance provides support for miniaturized microwave device applications. [ABSTRACT FROM AUTHOR]

The necessity for the creation of safe, dependable, biocompatible, and efficient methods to make nanoparticles drives an increasing number of researchers to consider using biological systems as potential eco-friendly nanofactories. Fungi have an innate ability to reduce and oxidize metal ions into metal oxide nanoparticles, thus behaving as nanofactories. In the present study, Trichoderma harzianum was used to prepare ZnO nanoparticles (ZnO NPS). ZnO NPS showed a peak at 370 nm upon testing using UV spectrophotometer and percentages of zinc(72.0±0.2 %) and oxygen(28.0 ±0.3) upon analysis using Edx with an irregular shape, 16.5 nm size and characterized XRD pattern. Soymilk as well as the prepared ZnONPs were investigated either separately or in their mixture (1:1) for their antibacterial and anti-tumor effects. The mixture showed a promising antibacterial impact on Enterococcus faecalis (ATCC29212) and Escherichia coli (ATCC25922) which was confirmed using a transmission electron microscope. ZnONPs mixed with soymilk showed a promising anti-tumor action towards human colorectal adenocarcinoma cell line Caco-2 through boosting apoptotic rate, which was detected by flow cytometry. The current report highlights the possibility of mixing eco-friendly biosynthesized nanoparticles with natural products to enhance their biomedical impact with minimal toxicity as possible innovative pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) have significant environmental concerns for soil, water and ecosystems. Since their harmful effects on human health, including respiratory disease, they are considered dangerous substances. Thus, it is required to discover a constructive solution to decrease of MWCNT toxicity. Due to their high degradability, white rot and soft rot fungi have been used in the biodegradation of various pollutants. In this study, we evaluated the ability of native Iranian white and soft rot fungi to degrade MWCNTs mainly by means of dynamic light scattering (DLS) and surface charge measurement. In this regard, growth kinetics, CO2 and protein production, size, surface charge and pH change were measured. Continuous Raman spectroscopy, scanning electron microscope (SEM) and transmission electron microscope (TEM) imaging were carried out to detect the process of degradation. The results showed that the morphology, arrangement, size and diameter of MWCNTs were modified due to fungal degradation. The cytotoxicity of treated MWCNTs was determined by the MTT test. The results indicated that native Iranian white and soft rot fungi have a significant ability for degradation of MWCNTs. Furthermore, it could be concluded that fungal treatment could reduce the toxicity of MWCNTs and the best result was achieved in 500 ppm MWCNTs for Trichoderma sp. The activities of oxidative enzymes such as laccase, manganese peroxidase (MnP) and lignin peroxidase (LiP) were measured to determine the mechanism of degradation. Enzyme assays have suggested that these oxidising enzymes especially laccase might play a key role in the degradation of MWCNTs in white rot and soft rot fungi. The overall results confirmed the reproductive ability of Trichoderma sp. WF29 as a soft rot and two white rot fungi Irpex lacteus WF36 and Trametes versicolor to degrade MWCNT. [ABSTRACT FROM AUTHOR]

Diatomaceous earth has been used as a nonorganic carrier to prepare a sodium humate modified diatomaceous space using the sol‐gel method. X‐ray diffraction, field emission scanning electron microscopy, transmission electron microscope, the Brunauer–Emmett–Teller (BET) method, and other methods were used to characterize its physio‐chemical properties. The effects of sodium humate/diatomite on the pH of tetracycline in water, the dosage of adsorbent, and pollutant temperature on the adsorption effect were studied. The results show that after alkali modification, the porous structure of diatomite remains undamaged, and the specific surface area of the modified sample is increased to 12.712 m2/g, and the average pore diameter is reduced to 146.19 nm. Adding 20‐mg sodium humate/diatomite into 100‐mL tetracycline wastewater with an initial concentration of 20 mg/L, and pH of 5 at a temperature of 55°C, the adsorption capacity reaches 75.1 mg/L, and the removal rate reaches 78.3%. The quasi‐second‐order kinetic model was fitted by regression and found to have R2 > 0.99, indicating that the adsorption process was one of surface adsorption. It is a process that involves initially rapid adsorption and then slowly reaching equilibrium. As an adsorption thermodynamics model, the Temkin, Redlich‐Peterson and Koble‐Corrigan models can explain humic acid sodium/diatomite behavior in the adsorption of tetracycline in water (each with R2 ≥ 0.99), and the effects of surface behavior in multilayer adsorption and electrostatic attraction on uneven heterogeneous adsorption. [ABSTRACT FROM AUTHOR]

In this study, nickel-cobalt@functionalized multi-walled carbon nanoparticles (NiCo@f-MWCNT NPs) were synthesized, analysed, and used for hydrogen generation via methanolysis on NaBH4. For the NPs synthesis, two steps were conducted (i.e., i: MWCNT was functionalized in an acid medium to support NPs (f-MWCNT); ii: NiCo NPs were synthesized and supplemented with f-MWCNT). Various characterization techniques were used to examine the morphological structure of NiCo@f-MWCNT NPs. The transmission electron microscope (TEM) results showed that the NPs were sized as 3.941 ± 1.094 nm with a spherical structure. The X-ray diffraction analysis (XRD) results indicated an average crystalline size of 1.46 nm. The evaluation of the catalytic performance for hydrogen production revealed that the turnover frequency (TOF) was calculated to be 2934.4 min− 1 with activation energy (Ea) and enthalpy (∆H) of 39.29 kJ/mol and 36.74 kJ/mol, respectively, which indicates high viability for hydrogen transport and generation application and processes. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) - green synthesized using Cassia fistula fruit pulp extract - was selected as the composite partner to cerium doped tin oxide (SnO 2 :Ce) to prepare SnO 2 :Ce/rGO nanocomposite and its photocatalytic ability was determined by degrading a cationic (Methylene Blue (MB)) and an anionic dye (Rose Bengal (RB)). Its biomedical application potential was analyzed through the antioxidant assays 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and superoxide, and anti-diabetic assay α-glucosidase. The nanocomposite exhibits superior dye degrading efficiency of 98% and 97% for MB and RB, respectively. The long hetero-junction formed between the composite partners as observed from the Transmission Electron Microscope (TEM) images facilitates charge recombination delay and desirable carrier transport. The rGO partnering makes the nanocomposite material visible light responsive photocatalyst by reducing the band gap. In the DPPH and super oxide free radical scavenging assays, the percentage inhibition of the free radicals for the nanocomposite was 89.38±0.14% with half-maximal inhibitory concentration (IC 50) of 79.68±1.39 μg/mL) and 86.93±0.11% with an IC 50 of 107.23±1.17 μg/mL, respectively. Similarly, the nanocomposite exhibited highest inhibition of 83.62 ± 0.73% (IC 50 of 186.40 ± 1.40 μg/mL) against the α-glucosidase enzyme. Thus the bio-friendly SnO 2 :Ce/rGO nanocomposite synthesized using Cassia fistula fruit pulp extract is promising for photocatalytic and many biomedical applications. [ABSTRACT FROM AUTHOR]

Corundum and transition alumina powders are commonly produced through the Bayer process—that is, by digestion of bauxite in a sodium hydroxide solution, followed by gibbsite precipitation, which contains significant amounts of Na+ ions. During the de‐hydroxylation of gibbsite, Na+ is associated with retardation of the structural phase transformations between transition alumina and corundum (α‐Al2O3) phases, although the exact role of Na is unclear. The influence of Na+ ions on the phase transformation of γ‐Al2O3 to α‐alumina was investigated by varying the concentration of NaOH in aqueous γ‐Al2O3 suspensions. The phase transformation behavior of γ‐Al2O3 was monitored through thermal analysis, X‐ray diffraction, scanning electron microscope, X‐ray photoelectron spectrometer (XPS), and transmission electron microscope. As the Na concentration in γ‐alumina suspensions increased, the amount of α‐Al2O3 decreased in samples that were heat treated at 1200°C for 2 h. XPS analysis indicated that washing transition alumina powders with NH4OH solutions had decreased the surface concentration of Na+ and facilitated the phase transformation to α‐Al2O3. [ABSTRACT FROM AUTHOR]

• With an increase in Si/Fe ratio, the Cr(VI) adsorption on Si-Fh decreases. • The electrostatic repulsion has a greater increase than complexation with Si-Fh. • DFT and surface characterization reveals the mechanism of Cr(VI) retention by Si-Fh. Hexavalent chromium [Cr(VI)] causes serious harm to the environment due to its high toxicity, solubility, and mobility. Ferrihydrites (Fh) are the main adsorbent and trapping agent of Cr(VI) in soils and aquifers, and they usually coexist with silicate (Si), forming Si-containing ferrihydrite (Si-Fh) mixtures. However, the mechanism of Cr(VI) retention by Si-Fh mixtures is poorly understood. In this study, the behaviors and mechanisms of Cr(VI) adsorption onto Si-Fh with different Si/Fe molar ratios was investigated. Transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and other techniques were used to characterize Si-Fh and Cr(VI)-loading of Si-Fh. The results show that specific surface area of Si-Fh increases gradually with increasing Si/Fe ratios, but Cr(VI) adsorption on Si-Fh decreases with increasing Si/Fe ratios. This is because with an increase in Si/Fe molar ratio, the point of zero charge of Si-Fh gradually decreases and electrostatic repulsion between Si-Fh and Cr(VI) increases. However, the complexation of Cr(VI) is enhanced due to the increase in adsorbed hydroxyl (A-OH-) on Si-Fh with increasing Si/Fe molar ratio, which partly counteracts the effect of the electrostatic repulsion. Overall, the increase in the electrostatic repulsion has a greater impact on adsorption than the additional complexation with Si-Fh. Density functional theory calculation further supports this observation, showing the increases in electron variation of bonding atoms and reaction energies of inner spherical complexes with the increase in Si/Fe ratio. [Display omitted] [ABSTRACT FROM AUTHOR]

Whether Mn carbonates can be used as a proxy for the oxygenation event is debated. Here we examined the Early Cretaceous lacustrine Mn carbonates from North China, which contain abundant microbial fossils. The extremely positive δ13C (up to +15‰ relative to Vienna Peedee belemnite) and micro‐area enrichment of Ni strongly indicate a methanogenic archaea origin of these microorganisms. Transmission electron microscope and electron energy loss spectroscopy show the nanoscale transformation of Mn‐oxides (Mg‐exchanged phyllomanganate) to Mn carbonates (kutnohorite), on extracellular polymeric substances. The reaction of the Mn oxides with organic matter resulted in increasing pH and alkalinity, together with the fluctuating pH, offering a suitable micro‐environment for the transformation processes. These Mn carbonates are therefore indicative of an oxidized, sulfate‐absent environment. The depicted scenario serves as a reference to ocean of the early Earth and provides a referable Mn oxide tracer for determining the emergence of the Great Oxidation Event. Plain Language Summary: Microbial‐mineral interactions have played an important role in the evolution of the Earth. Active methanogenesis exists in submerged sediments, and the biological activity of methanogen is directly or indirectly involved in the process of geochemical cycling and mineral precipitation. In modern ocean environments, the methanogenesis zone and the manganese reduction zone are respectively, located in the lower and upper layers of a chemical zone, so it is difficult for them to interact directly with each other. This study documents evidence for the direct reaction between them in the Early Cretaceous lacustrine sediment cores from north China. Precipitation of Mn carbonates was likely mediated by methanogenesis in couple with Mn oxide reduction. Such an environment resembles the oxygen oases in the ocean before the Great Oxidation Event and thus provides new insights into the marine environment at that time. Key Points: Abundant methanogen microfossils in Mn carbonates with positive δ13CNanoscale transformation from Mn oxides to Mn carbonatespH fluctuations due to changes in redox conditions promote the formation of kutnohorite [ABSTRACT FROM AUTHOR]

Whole lung engineering and the transplantation of its products is an ambitious goal and ultimately a viable solution for alleviating the donor-shortage crisis for lung transplants. There are several limitations currently impeding progress in the field with a major obstacle being efficient revascularization of decellularized scaffolds, which requires an extremely large number of cells when using larger pre-clinical animal models. Here, we developed a simple but effective experimental pulmonary bioengineering platform by utilizing the lung as a scaffold. Revascularization of pulmonary vasculature using human umbilical cord vein endothelial cells was feasible using a novel in-house developed perfusion-based bioreactor. The endothelial lumens formed in the peripheral alveolar area were confirmed using a transmission electron microscope. The quality of engineered lung vasculature was evaluated using box-counting analysis of histological images. The engineered mouse lungs were successfully transplanted into the orthotopic thoracic cavity. The engineered vasculature in the lung scaffold showed blood perfusion after transplantation without significant hemorrhage. The mouse-based lung bioengineering system can be utilized as an efficient ex-vivo screening platform for lung tissue engineering. [ABSTRACT FROM AUTHOR]

To expand the market capacity of p‐diethylbenzene (PDEB), core‐shell zeolite (TS‐1@MCM‐48) is designed as a catalyst for PDEB oxidation. TS‐1@MCM‐48 catalyst is synthesized by in‐situ crystallization method and characterized by X‐ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), N2 adsorption‐desorption, in‐situ electron paramagnetic resonance (EPR) and 29Si nuclear magnetic resonance (29Si MAS‐NMR). Oxidation of PDEB by H2O2 was investigated systematically in liquid phase. The conversion of PDEB over TS‐1@MCM‐48 was 28.1 % and the total selectivity was 72.6 %, where the selectivity of EAP (p‐ethylacetophenone) and EPEA (4‐ethyl‐α‐methylbenzyl alcohol) was 28.6 % and 44.0 %, respectively. Compared with TS‐1 and MCM‐48 zeolite, the conversion rate of reactants and the selectivity of products have been significantly improved. The catalytic performance of TS‐1@MCM‐48 is derived from its well‐crystallized microporous core and mesoporous shell with regular channels, which make active sites of TS‐1 zeolite in the catalyst be fully utilized and mass transfer resistance be largely reduced. Further through theoretical calculation, we propose that the oxidation of PDEB is the result of the combination and mutual transformation of free radical process and carbocation process. Core‐shell structure ensures the conversion rate of raw materials and improves the selectivity of products. [ABSTRACT FROM AUTHOR]

The harsh service environment of aeroengine hot-end components requires superalloys possessing excellent antioxidant properties. This study investigated the effect of pre-strain on the oxidation behavior of polycrystalline Ni3Al-based superalloys. The growth behaviors of oxidation products were analyzed by scanning electron microscope, transmission electron microscope, X-ray Photoelectron Spectroscopy and Raman spectroscopy. The results indicated that the 5% pre-strained alloys exhibited lower mass gain, shallower oxidation depth and more compact oxide film structures compared to the original alloy. This is mainly attributed to the formation of rapid diffusion paths for Al atoms diffusing to the surface under 5% pre-strain, which promotes the faster formation of protective Al2O3 film while continuing to increase the pre-strain to 25% results in less protective transient oxidation behavior being aggravated due to the increase in dislocation density within the alloy, which prevents the timely formation of the protective Al2O3 film, resulting in uneven oxidation behavior on the alloy. [ABSTRACT FROM AUTHOR]

Dressings with multiple functional performances (such as hemostasis, promoting regeneration, analgesia, and anti-inflammatory effects) are highly desired in orthopedic surgery. Herein, several new kinds of medicated nanofibers loaded with several active ingredients for providing multiple functions were prepared using the modified coaxial electrospinning processes. With an electrospinnable solution composed of polycaprolactone and fenoprofen as the core working fluid, several different types of unspinnable fluids (including pure solvent, nanosuspension containing tranexamic acid and hydroxyapatite, and dilute polymeric solution comprising tranexamic acid, hydroxyapatite, and polyvinylpyrrolidone) were explored to implement the modified coaxial processes for creating the multifunctional nanofibers. Their morphologies and inner structures were assessed through scanning and transmission electron microscopes, which all showed a linear format without the discerned beads or spindles and a diameter smaller than 1.0 μm, and some of them had incomplete core–shell nanostructures, represented by the symbol @. Additionally, strange details about the sheaths' topographies were observed, which included cracks, adhesions, and embedded nanoparticles. XRD and FTIR verified that the drugs tranexamic acid and fenoprofen presented in the nanofibers in an amorphous state, which resulted from the fine compatibility among the involved components. All the prepared samples were demonstrated to have a fine hydrophilic property and exhibited a lower water contact angle smaller than 40° in 300 ms. In vitro dissolution tests indicated that fenoprofen was released in a sustained manner over 6 h through a typical Fickian diffusion mechanism. Hemostatic tests verified that the intentional distribution of tranexamic acid on the shell sections was able to endow a rapid hemostatic effect within 60 s. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) severely affects patients' quality of life and is commonly treated with glucocorticosteroids injections, like dexamethasone, which may have side effects. This study aimed to create a novel low dose of twin-drug hydrogel containing dexamethasone and diclofenac and explore its potential as a drug delivery system for an enhanced anti-inflammatory effect. Its characterization involved rheology, transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Furthermore, the hydrogel demonstrated thixotropic properties. The hydrogel exhibited no cytotoxicity against RAW 264.7 macrophages. Furthermore, the hydrogel demonstrated a significant anti-inflammatory efficacy by effectively downregulating the levels of NO, TNF-α, and IL-6 in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. The co-delivery approach, when intra-articularly injected in adjuvant-induced arthritis (AIA) rats, significantly alleviated chronic inflammation leading to reduced synovitis, delayed bone erosion onset, and the downregulation of inflammatory cytokines. The biocompatibility and adverse effect evaluation indicated good biological safety. Furthermore, the hydrogel demonstrated efficacy in reducing NF-κB nuclear translocation in LPS-induced RAW 264.7 macrophages and inhibited p-NF-kB, COX-2, and iNOS expression both in RAW 264.7 macrophages and the joints of AIA rats. In conclusion, the findings indicate that the hydrogel possesses potent anti-inflammatory activity, which effectively addresses the limitations associated with free forms. It presents a promising therapeutic strategy for the management of RA. [ABSTRACT FROM AUTHOR]

In this work, UV-Vis spectrophotometry, High Resolution Scanning Transmission Electron Microscopes and selected experimental conditions were used to screen the colloidal system. The obtained results complement the established knowledge regarding the mechanism of nanoparticle formation. The process of gold nanoparticles formation involves a two-step reduction of Au ions to Au(0); atom association and metastable cluster formation; autocatalytic cluster growth; ultra-small particle formation (1–2 nm, in diameter); particle growth and larger particles formation; and further autocatalytic crystal growth (D > 100 nm). As a reductant of Au(III) ions, a cinnamon extract was used. It was confirmed that eugenol as one of the cinnamon extract compounds is responsible for fast Au(III) ion reduction, whereas cinnamaldehyde acts as a gold-particle stabilizer. Spectrophotometry studies were carried out to track kinetic traces of gold nanoparticle (D > 2 nm) formation in the colloidal solution. Using the Watzky—Finke model, the rate constants of nucleation and autocatalytic growth were determined. Moreover, the values of energy, enthalpy and entropy of activation for stages related to the process of nanoparticle formation (Index 1 relates to nucleation, and Index 2 relates to the growth) were determined and found to be E1 = 70.6 kJ, E2 = 19.6 kJ, ΔH1 = 67.9 kJ/mol, ΔH2 = 17 kJ/mol, ΔS1 = −76.2 J/(K·mol), ΔS2 = −204.2 J/(K·mol), respectively. In this work the limitation of each technique (spectrophotometry vs. HRSTEM) as a complex tool to understand the dynamic of the colloidal system was discussed. [ABSTRACT FROM AUTHOR]

Nanostructures have been used for various biomedical applications due to their optical, antibacterial, magnetic, antioxidant, and biocompatible properties. Cancer is a prevalent disease that severely threatens human life and health. Thus, innovative and effective therapeutic approaches are urgently required for cancer. Photothermal therapy (PTT) is a promising approach to killing cancer cells. In this investigation, we developed a low‐cost, simple, green technique to fabricate molybdenum trioxide nanostructures (MNs) using Opuntia ficus‐indica mucilage as a template. Moreover, the MNs were functionalized with folic acid (FA) for cancer PTT. The X‐ray diffractometer results revealed that the prepared MNs have an orthorhombic crystal phase. The transmission electron microscope image of MNs shows a flake shape with 20–150 nm diameter. The cytotoxicity of MNs and FA‐conjugated MNs was studied in vitro. These cell viability assay results suggested that fabricated MoO3 nanostructures reduced 25% of cell viability in MCF‐7 cells, even at high doses. However, even with high‐dose treatment, FA/MNs do not cause significant cell death. Acridine orange/ethidium bromide (AO/EB) staining revealed DNA and chromatin condensation in MCF‐7 cells exposed to MNs. Overall, the in vitro study results suggested that FA/MNs have excellent biocompatibility, which applies to biomedical applications. MNs dispersion temperature gradually increases from 26 to 58°C under 808 nm laser irradiation. We found significant mortality rates after NIR irradiation in MNs‐ or FA/MNs‐treated MCF‐7 cells. These findings suggest that FA/MNs can be used as an effective photothermal agent to treat breast cancer. [ABSTRACT FROM AUTHOR]

STUDY QUESTION What is the significance and mechanism of human seminal plasma extracellular vesicles (EVs) in regulating human sperm functions? SUMMARY ANSWER EV increases the intracellular Ca2+ concentrations [Ca2+]i via extracellular Ca2+ influx by activating CatSper channels, and subsequently modulate human sperm motility, especially hyperactivated motility, which is attributed to both protein and non-protein components in EV. WHAT IS KNOWN ALREADY EVs are functional regulators of human sperm function, and EV cargoes from normal and asthenozoospermic seminal plasma are different. Pre-fusion of EV with sperm in the acidic and non-physiological sucrose buffer solution could elevate [Ca2+]i in human sperm. CatSper, a principle Ca2+ channel in human sperm, is responsible for the [Ca2+]i regulation when sperm respond to diverse extracellular stimuli. However, the role of CatSper in EV-evoked calcium signaling and its potential physiological significance remain unclear. STUDY DESIGN, SIZE, DURATION EV isolated from the seminal plasma of normal and asthenozoospermic semen were utilized to investigate the mechanism by which EV regulates calcium signal in human sperm, including the involvement of CatSper and the responsible cargoes in EV. In addition, the clinical application potential of EV and EV protein-derived peptides were also evaluated. This is a laboratory study that went on for more than 5 years and involved more than 200 separate experiments. PARTICIPANTS/MATERIALS, SETTING, METHODS Semen donors were recruited in accordance with the Institutional Ethics Committee on human subjects of the Affiliated Hospital of Nantong University and Jiangxi Maternal and Child Health Hospital. The Flow NanoAnalyzer, western blotting, and transmission electron microscope were used to systematically characterize seminal plasma EV. Sperm [Ca2+]i responses were examined by fluorimetric measurement. The whole-cell patch-clamp technique was performed to record CatSper currents. Sperm motility parameters were assessed by computer-assisted sperm analysis. Sperm hyperactivation was also evaluated by examining their penetration ability in viscous methylcellulose media. Protein and non-protein components in EV were analyzed by liquid chromatography-mass spectrum. The levels of prostaglandins, reactive oxygen species, malonaldehyde, and DNA integrity were detected by commercial kits. MAIN RESULTS AND THE ROLE OF CHANCE EV increased [Ca2+]i via an extracellular Ca2+ influx, which could be suppressed by a CatSper inhibitor. Also, EV potentiated CatSper currents in human sperm. Furthermore, the EV-in [Ca2+]i increase and CatSper currents were absent in a CatSper-deficient sperm, confirming the crucial role of CatSper in EV induced Ca2+ signaling in human sperm. Both proteins and non-protein components of EV contributed to the increase of [Ca2+]i, which were important for the effects of EV on human sperm. Consequently, EV and its cargos promoted sperm hyperactivated motility. In addition, seminal plasma EV protein-derived peptides, such as NAT1-derived peptide (N-P) and THBS-1-derived peptide (T-P), could activate the sperm calcium signal and enhance sperm function. Interestingly, EV derived from asthenozoospermic semen caused a lower increase of [Ca2+]i than that isolated from normal seminal plasma (N-EV), and N-EV significantly improved sperm motility and function in both asthenozoospermic samples and frozen-thawed sperm. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION This was an in vitro study and caution must be taken when extrapolating the physiological relevance to in vivo regulation of sperm. WIDER IMPLICATIONS OF THE FINDINGS Our findings demonstrate that the CatSper-mediated-Ca2+ signaling is involved in EV-modulated sperm function under near physiological conditions, and EV and their derivates are a novel CatSper and sperm function regulators with potential for clinical application. They may be developed to improve sperm motility resulting from low [Ca2+]i response and/or freezing and thawing. STUDY FUNDING/COMPETING INTEREST(S) This research was supported by the National Natural Science Foundation of China (32271167), the Social Development Project of Jiangsu Province (BE2022765), the Nantong Social and People's Livelihood Science and Technology Plan (MS22022087), the Basic Science Research Program of Nantong (JC22022086), and the Jiangsu Innovation and Entrepreneurship Talent Plan (JSSCRC2021543). The authors declare no conflict of interest. [ABSTRACT FROM AUTHOR]

In this article, the effect of Ce element on the microstructure and mechanical properties was studied by Ce addition to the hot‐formed steel. Scanning electron microscope and energy dispersive spectrometer (SEM‐EDS) was used to analyze the improvement effect of Ce on inclusions and the effect of inclusions on fracture behavior; Electron back scattering diffractometer (EBSD) was used to analyze the refinement and strengthening effect of Ce on martensitic grains; transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM) was used to analyze the microstructure strengthening effect and microalloying effect of solid solution Ce in hot‐formed steel. Through a systematic analysis of mechanical properties and microstructure, the mechanism of Ce enhances the strength and elongation of hot‐formed steel was clarified. Besides, this work provides a research basis for further improving the safety and machinability of hot‐formed steel. [ABSTRACT FROM AUTHOR]

The modified 9Cr–1Mo steel and Inconel (IN) 617 superalloy are high‐temperature alloys of prime importance in several industrial applications. Both of these are used at elevated temperature for various piping and tubing components and undergo asymmetric cyclic loading; therefore, it is highly essential to assess their resistance to accumulation of inelastic strain (ratcheting) under asymmetric stress cycling. In this study, ratcheting behavior of these alloys is compared at the homologous temperature of 0.42, under uniaxial asymmetric stress loading with positive mean stress. Deformation behavior of the tested samples is analyzed by transmission electron microscope. While there is homogeneous deformation in the modified 9Cr–1Mo steel, there is intersection of slip bands and presence of dislocation tangles in the IN 617 alloy. Fracture surface of the modified 9Cr–1Mo steel, tested under asymmetric cyclic loading, reveals typical ductile fracture resulting from tensile loading, whereas there is characteristic fatigue fracture of the IN 617 alloy. [ABSTRACT FROM AUTHOR]

A high throughput ionic liquid-based catalytic system as a new efficient and reusable heterogeneous nanocatalyst was developed for the one-pot synthesis of some 1H-pyrazolo [1,2-b] phthalazine-5,10-diones in ethanol at 78 °C. The designed nanocatalyst was synthesized and then characterized for their functionality, composition, size, morphology, surface properties, and crystalline size by Fourier-transform infrared spectroscopy (FTIR), Energy dispersive X-ray, Transmission electron microscopes, Field emission scanning electron microscopy, Brunauer–Emmett–Teller, and X-Ray diffraction techniques. The target products were obtained in high to excellent yields (80–96%) in this protocol. The structure of all synthesized products was determined via hydrogen nuclear magnetic resonance (1H NMR) and FT-IR spectra. This eco‐friendly method has advantages such as a clean reaction profile, low amount of the catalyst, mild reaction conditions, environmentally benign solvent, short reaction times and high to excellent yield of products. Moreover, there is no remarkable loss in the catalytic activity of perlite NPs/SiO2/IL after six cycles of reuse. Also, the results of hot filtration studies show that leaching is not occur in catalyst surfaces and prove the complete heterogeneous behavior of perlite NPs/SiO2/IL under optimized reaction conditions. [ABSTRACT FROM AUTHOR]

In this study, montmorillonite clay (MT) was modified for the first time with CuFe2O4 spinel ferrite nanoparticles and assessed as a recyclable catalyst for the one-pot synthesis of 1,3-thiazolidin-4-ones under solvent-free microwave irradiation conditions with a high to excellent yield. The morphology and chemistry of the CuFe2O4@MT (CuF@MT) nanocomposite were characterized using X-ray diffraction (XRD) patterns, field-emission scanning electron microscopy (FE-SEM) images, transmission electron microscope images, and vibrating sample magnetometer curve analyses. The results indicated the presence of CuFe2O4 with a tetragonal structure, a consistent distribution, and no aggregation at MT. The findings further indicated that CuF@MT's superior magnetic characteristics led to its use as a heterogeneous catalyst in manufacturing 1,3-thiazolidin-4-one derivatives. This technique offers various advantages, including mild reaction conditions, high efficiency, and fast recovery of the nanocatalyst. [ABSTRACT FROM AUTHOR]

In the current study, a novel electrochemical sensor has been developed for levofloxacin detection, by coating an Indium tin oxide (ITO) modified electrode with a thin film of Cu-nanoplatelets, WO3 quantum dots coupled to the g-C3N4 nanosheets. The prepared electrode was characterized using various analytical tools, including powder X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM) and Fourier-Transform Infrared spectroscopy (FT-IR). The electrochemical properties of levofloxacin (LEVO) were determined by performing cyclic voltammetry (CV) and amperometric tests. The hybrid electrode exhibits a well-defined peak around 1.2 V during the anodic potential scan, which was attributed to the (LEVO) oxidation process. The measured ultrahigh sensitivity is 0.786 µA µM−1 cm−2 for a linear range of 0–70 µM in the low concentration zone and 0.312 µA µM−1 cm−2 for a linear range of 120–870 µM in the high concentration zone. A good linear correlation between the peak current and LEVO concentration in the range of 0 to 70 µM was obtained through detection and quantification limits of 0.1 µM and 0.3 µM, respectively.The WO3/g-C3N4/Cu nanoparticles that modified the ITO electrode reveals high stability, reproducibility, and repeatability, as well as selectivity for LEVO in real water samples. Analyses were also conducted on the LEVO detection in the presence of interfering substances.As far as this paper is concerned, this is the first time that a ternary nanocomposite WO3/g-C3N4/Cu has been used to detect LEVO at low and high concentrations. Application of ITO/WO3/g-C3N4/Cu as an electrochemical sensor for LEVO [ABSTRACT FROM AUTHOR]

The aim of this work was to formulate zaltoprofen (ZLT) loaded polyvinyl pyrrolidone K30 (PVP K30) nanodispersions to improve the solubility of ZLT. By varying the concentrations of PVP K30 and poloxamer 407 (1:1, 1:2, 2:1 and 2:2) different trials of ZLT nanodispersions were developed by solvent evaporation technique. The effects of formulation variables on the particle size, zeta potential, drug content, and encapsulation efficiency of ZLT loaded nanodispersions (ZLTNDs) were investigated. The average particle size, zeta potential, drug content and entrapment efficiency of ZLT nanodispersions (ZLTNDs-4) were 285.40 ± 16.41 nm, −19.06 ± 1.50 mV, 73.11 ± 0.16 mg, and 91.37 ± 0.22%, respectively. The spherical shape of the nanodispersion was verified by Transmission Electron Microscope (TEM) analysis. Further the developed formulation was characterized using Fourier Transform Infrared Spectroscopy and Differential scanning calorimetry (DSC) analysis. The in vitro release studies revealed maximum ZLT release 95.78 ± 0.85% compared to pure ZLT 36.47 ± 0.84%. The in vitro anti-inflammatory effect of pure ZLT, ZLTNDs-4 and standard drug (diclofenac sodium) was tested by protein denaturation assay, and the results exhibited superior anti-inflammatory activity of ZLTNDs-4 was 33.33 ± 1.00%). The anti- angiogenesis assay (CAM assay) results indicated that absence of vascular inhibition compared to pure ZLT. The results of the present work can be used to enhance the poorly aqueous soluble of ZLT and may be extended for other hydrophobic compounds, benefiting the pharmaceutical industries, etc. [ABSTRACT FROM AUTHOR]

During glass production, phase separation can result in the formation of suspended liquid droplets, which can cause changes in the system rheology. In nuclear waste vitrification context, some new glassy matrices may present this phase separation matter, but the mechanisms controlling the viscosity changes have not yet been determined. Here, we measure the viscosity of a sodium‐borosilicate melt containing dissolved MoO3 at different temperatures and subject to different applied shear strain rates. We observe that (i) the viscosity increases sharply as the temperature decreases and (ii) at any constant temperature below 1000°C, the system presents non‐Newtonian response. Using transmission electron microscope observations coupled with viscosity calculations, we interpret the cause of the observed changes as the result of phase separation. We show that the viscosity increase on cooling is in excess of the predicted temperature dependence for a homogeneous melt of the starting composition. The increase is due to the formation of a second phase and is controlled by chemical and structural modifications of the matrix during the loss of the elements that form the droplets. This work provides insights into the rheology of a system composed of two composition sets due to a miscibility gap. [ABSTRACT FROM AUTHOR]

Among two-dimensional (2D) transition metal dichalcogenides (TMDs), MoTe2 is predestined for phase-engineering applications due to the small difference in free energy between the semiconducting H-phase and metallic 1T′-phase. At the same time, the complete picture of the phase evolution originating from point defects in single-layer of semiconducting H-MoTe2 via Mo6Te6 nanowires to cubic molybdenum has not yet been reported so far, and it is the topic of the present study. The occurring phase transformations in single-layer H-MoTe2 were initiated by 40–80 kV electrons in the spherical and chromatic aberration-corrected high-resolution transmission electron microscope and/or when subjected to high temperatures. We analyse the damage cross-section at voltages between 40 kV and 80 kV and relate the results to previously published values for other TMDs. Then we demonstrate that electron beam irradiation offers a route to locally transform freestanding single-layer H-MoTe2 into one-dimensional (1D) Mo6Te6 nanowires. Combining the experimental data with the results of first-principles calculations, we explain the transformations in MoTe2 single-layers and Mo6Te6 nanowires by an interplay of electron-beam-induced energy transfer, atom ejection, and oxygen absorption. Further, the effects emerging from electron irradiation are compared with those produced by in situ annealing in a vacuum until pure molybdenum crystals are obtained at temperatures of about 1000 °C. A detailed understanding of high-temperature solid-to-solid phase transformation in the 2D limit can provide insights into the applicability of this material for future device fabrication. [ABSTRACT FROM AUTHOR]

Owing to their improved catalytic stability and ability to undergo repeated cycles, solid-supported catalysts show great potential for various catalytic reactions. In this study, we synthesized a catalyst comprising a palladium-2,2-bipyridine complex supported on TiO2 nanoparticles (TiO2@BDP-PdCl2) fully characterised and investigated its efficacy in Suzuki–Miyaura cross coupling reactions involving phenyl boronic acid with various aryl halides under mild reaction conditions. The 2,2′- bipyridine (bp) has shown excellent complexation properties for Pd (II) and it could be easily anchored onto functionalized TiO2 support by the bridging carboxylate ions. The composition and structure of the as-prepared catalyst was characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Transmission Electron Microscope (TEM), X-ray photoelectron spectroscopy (XPS), and UV–Vis spectroscopy. The catalyst easily demonstrated separability, enhancing its practicality in catalytic processes. Subsequent utilization showed a consistent activity level, suggesting the stabilization of the aggregated catalyst species. This research sheds light on the importance of catalyst stability and maintenance during consecutive reaction cycles. [ABSTRACT FROM AUTHOR]

Breaking the D4h symmetry in the square‐planar M−N4 configuration of macrocycle molecular catalysts has witnessed enhanced electrocatalytic activity, but at the expense of electrochemical stability. Herein, we hypothesize that the lability of the active Cu−N3 motifs in the N‐confused copper (II) tetraphenylporphyrin (CuNCP) could be overcome by applying pulsed potential electrolysis (PPE) during electrocatalytic carbon dioxide reduction. We find that applying PPE can indeed enhance the CH4 selectivity on CuNCP by 3 folds to reach the partial current density of 170 mA cm−2 at >60 % Faradaic efficiency (FE) in flow cell. However, combined ex situ X‐ray diffraction (XRD), transmission electron microscope (TEM), and in situ X‐ray absorption spectroscopy (XAS), infrared (IR), Raman, scanning electrochemical microscopy (SECM) characterizations reveal that, in a prolonged time scale, the decomplexation of CuNCP is unavoidable, and the promoted water dissociation under high anodic bias with lowered pH and enriched protons facilitates successive hydrogenation of *CO on the irreversibly reduced Cu nanoparticles, leading to the improved CH4 selectivity. As a key note, this study signifies the adaption of electrolytic protocol to the catalyst structure for tailoring local chemical environment towards efficient CO2 reduction. [ABSTRACT FROM AUTHOR]

Silicon nitride (Si3N4) has great potential for applications in photoelectric and semiconductor fields. In this study, a novel strategy of fabricating Si3N4 crystals is reported, and the morphology of α-Si3N4 can be controlled. The aBN/SiO2/Si wafers were designed and irradiated by a high-energy electron beam for 2 min using home-made equipment. Tree-like α-Si3N4 dendrites and [001]-oriented unbranched α-Si3N4 whiskers can be synthesized by controlling the electron beam energy. Related formation mechanisms were analyzed based on componential and structural characterization using a scanning electron microscope and high-resolution transmission electron microscope. In addition, photoluminescence measurements indicate that the synthesized α-Si3N4 exhibit unique photoluminescence properties. This is attributed to α-Si3N4 forming abundant Si–Si bonds, Si dangling bonds, N dangling bonds and oxygen bonds in the synthesis process. These findings provide new insights into fabricating high-quality Si3N4 crystals, as well as developing related high-performance micro- or nano-devices. [ABSTRACT FROM AUTHOR]

SiC@C composites are extensively used in high-temperature metallurgy owing to their distinctive physicochemical properties. In this study, SiC@C composites with a core-shell structure were synthesized using silicon powder and Fe 2 O 3 as the silicon source and catalyst, respectively. The effect of various temperatures on the synthesis of the SiC@C composites was investigated. The results indicated that a SiC whiskers layer covers the graphite surface at 1600 °C. At this temperature, the production of silicon carbide reaches 9.2 %. Transmission electron microscope (TEM) revealed that the preferred growth orientation of SiC was the (111) crystal plane. Based on density functional theory, the adsorption properties of different crystal planes of SiC crystals and their interactions with Fe atoms on the crystal surface were investigated. The results showed that the adsorption properties of different SiC crystal planes varied, with the (111) crystal plane exhibiting the strongest adsorption ability. In the presence of Fe atoms, the adsorption properties of the (111) crystal plane reaches to a value of −2686.5253 Ha, indicating that Fe atoms can promote the adsorption of other atoms or molecules on the surface of SiC crystals. Additionally, the wettability of the SiC@C composites was improved, as evidenced by the decrease in the contact angle from 109° to 46°. [ABSTRACT FROM AUTHOR]

Synaptic plasticity changes in presynaptic terminals or postsynaptic membranes play a critical role in cognitive impairments and emotional disorders, but the underlying molecular mechanisms in depression remain largely unknown. The regulation effects of F-box and leucine-rich repeat protein 20 (FBXL20), vesicular glutamate transporter 1 (VGLUT1) and vesicle-associated membrane protein 1 (VAMP1) on synaptic plasticity and depressive-like behaviors examined by proteomics analysis, viral stereotaxic injection, transmission electron microscope and biochemical methods. The glutamate release detected by fluorescent probe in cultured primary pyramidal neurons. We found that chronic unpredictable mild stress (CUMS) induced significant synaptic deficits within hippocampus of depressed rats, accompanied with the decreased expression of VGLUT1 and VAMP1. Moreover, knockdown of VGLUT1 or VAMP1 in hippocampal pyramidal neurons resulted in abnormal glutamatergic neurotransmitter release. In addition, we found that the E3 ubiquitin ligase FBXL20 was increased within hippocampus, which may promote ubiquitination and degradation of VGLUT1 and VAMP1, and thus resulted in the reduction of glutamatergic neurotransmitter release, the disruptions of synaptic transmission and the induction of depression-like behaviors in rats. In contrast, shRNA knockdown of FBXL20 within the hippocampus of depressed rats significantly ameliorated synaptic damage and depression-like behaviors. Only one type of depression model was used in the present study, while other animal models should be used in the future to confirm the underlying mechanisms reported here. This study provides new insights that inhibiting FBXL20 pathway in depressed rats may be an effective strategy to rescue synaptic transmission and depression-like behaviors. [Display omitted] • Stress induced synaptic plasticity impairment in hippocampal CA1 region of CUMS high-susceptible rats. • Stress reduced the expression of VGLUT1 and VAMP1 in hippocampal CA1 region of CUMS high-susceptible rats. • VGLUT1 knockdown or VAMP1 knockdown resulted in reduced glutamate release from cultured primary neurons. • FBXL20 knockdown leads to elevated expression of VGLUT1 and VAMP1. • FBXL20 knockdown improves synaptic plasticity impairment and depression-like behavior. [ABSTRACT FROM AUTHOR]

Here, we synthesized nanocomposites of poly(methyl methacrylate/N,Ndimethylaminoethyl methacrylate/acrylic acid) [poly(MMA/DMAEMA/AA)] incorporated with cadmium oxide (CdO), copper oxide (CuO), manganese oxide (MnO2), and selenium oxide (SeO2) nanoparticles via microemulsion polymerization. Fourier-transform infrared spectroscopy (FT-IR), x-ray diffraction (XRD) analysis, transmission electron microscope (TEM), thermogravimetric analysis (TGA) as well as electrochemical techniques like cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were utilized to determine and understand the physico-chemical features of the polymers (MMA/DMAEMA/AA) and their embedded metal oxide (MO) nanoparticles. According to the TEM results, well-defined nanospheres of the pure polymer and its composite were obtained in the range of 45-75 nm, respectively. The electrochemical characteristics of all CdO, CuO, MnO2, and SeO2-based nanocomposites showed significant improvement, with capacitance values higher than those of the poly(MMA/DMAEMA/AA) nanosphere assemblies alone. Therefore, the nanocomposites were tested for direct hydrogen peroxide sensing along with direct transfer of electrons. The amperometry results showed a fast linear sensitivity in the range of 1-1000 µM with a lower detection limit of 0.03 µM. As a result, these materials could be recommended for battery storage and hydrogen peroxide sensing devices due to the significantly improved electrochemical properties offered by the synthesized nanocomposites. Highlights • Microemulsion polymerization of nanocomposites incorporated with nanoparticles. • The nanoparticles improve the nanocomposites' electro capacitance values. • The developed nanocomposites exhibit supercapacitors and energy storage. • The novel nanocomposites enable direct and fast hydrogen peroxide sensing. [ABSTRACT FROM AUTHOR]

Current flowing through heavy metals generates spin current by the spin Hall effect (SHE), and spin current exerts a torque on the adjacent magnetic layer, thereby switching the magnetization direction of the magnetic layer. Normally, an external magnetic field must be used to break symmetry in the response to the SHE torque, to realize deterministic switching. However, the presence of magnetic fields increases the difficulty in integrating spintronic devices with complementary metal-oxide-semiconductor. Thus, field-free spin–orbit torque switching has been a research hotspot. Here, symmetry-breaking has been realized by tilting the sample during the annealing process, resulting in a non-uniform diffusion of Ta atoms in the samples along the temperature gradient (x-direction), which was confirmed by transmission electron microscope mapping. As a result, the sample has demonstrated deterministic switching, in the absence of an external magnetic field, with a switching ratio of up to 88% and the critical current density of 1.5 × 107 A/cm2. Tilting annealing is a simple approach to achieve field-free switching. [ABSTRACT FROM AUTHOR]

Synthesis of crystalline zinc copper ferrite nanoparticles was achieved via a simple co-precipitation method. Scanning electron microscope (SEM) is utilized to give the morphological characterization of the prepared samples. A transmission electron microscope (TEM) was employed for further identification and confirmation of the particle size and morphology. Moreover, X-ray diffraction (XRD) and Fourier transformation infrared (FTIR) spectroscopy were utilized to examine crystalline structure and chemical structure, respectively. The photocatalytic performance of Zn0.5Cu0.5Fe2O4 nanoparticles under UV light was assessed by decolorization of methyl orange (MO) azo dye. The efficiency of photocatalytic degradation of 20 ppm of MO by Zn0.5Cu0.5Fe2O4 nanoparticles 15 mg was 96% after 135 min at an ambient temperature of 25 °C and pH value of 3. Further interpretation was carried out and a proposed mechanism for the MO photodegradation over Zn0.5Cu0.5Fe2O4 nanoparticles was suggested. [ABSTRACT FROM AUTHOR]

Background and objectives: Microbial cells capability to tolerate the effect of various antimicrobial classes represent a major worldwide health concern. The flexible and multi-components nanocomposites have enhanced physicochemical characters with several improved properties. Thus, different biological activities of biosynthesized starch/silver-selenium nanocomposite (St/Ag-Se NC) were assessed. Methodology: The St/Ag-Se NC was biosynthesized using Cladosporium cladosporioides CBS 174.62 (C. cladosporioides) strain. The shape and average particle size were investigated using scanning electron microscope (SEM) and high-resolution transmission electron microscope (HR-TEM), respectively. On the other hand, the St/Ag-Se NC effect on two cancer cell lines and red blood cells (RBCs) was evaluated and its hydrogen peroxide (H2O2) scavenging effect was assessed. Moreover, its effects on various microbial species in both planktonic and biofilm growth forms were examined. Results: The St/Ag-Se NC was successfully biosynthesized with oval and spherical shape and a mean particle diameter of 67.87 nm as confirmed by the HR-TEM analysis. St/Ag-Se NC showed promising anticancer activity toward human colorectal carcinoma (HCT-116) and human breast cancer (MCF-7) cell lines where IC50 were 21.37 and 19.98 µg/ml, respectively. Similarly, little effect on RBCs was observed with low nanocomposite concentration. As well, the highest nanocomposite H2O2 scavenging activity (42.84%) was recorded at a concentration of 2 mg/ml. Additionally, Staphylococcus epidermidis (S. epidermidis) ATCC 12,228 and Candida albicans (C. albicans) ATCC 10,231 were the highly affected bacterial and fungal strains with minimum inhibitory concentrations (MICs) of 18.75 and 50 µg/ml, respectively. Moreover, the noticeable effect of St/Ag-Se NC on microbial biofilm was concentration dependent. A high biofilm suppression percentage, 87.5% and 68.05%, were recorded with S. epidermidis and Staphylococcus aureus (S. aureus) when exposed to 1 mg/ml and 0.5 mg/ml, respectively. Conclusion: The biosynthesized St/Ag-Se NC showed excellent antioxidant activity, haemocompatibility, and anti-proliferative effect at low concentrations. Also, it exhibited promising antimicrobial and antibiofilm activities. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) doped antimony tungstate microflowers, prepared through hydrothermal process, have been investigated for simultaneous adsorption and photocatalysis. The pattern of evolution of microflower structures, however, can be tailored by the synthesis period. This change is observed from the field effect scanning electron microscope and transmission electron microscope images. A possible mechanism behind this morphological change has been developed. An argument based on the zeta potential may be responsible for this distinct morphology due to the strong electrostatic interactions. The variation of a particular x-ray diffraction peak corresponding to the plane { 012 } with variation of Ru doping percentage shows the decrease in crystallinity along the perpendicular direction to this plane. Besides, the optimum Ru doping percentage is evaluated on the basis of photocatalytic efficiency towards methylene blue (MB) degradation under visible light. The highest dye removal efficiency is observed for 2% Ru doped Sb2WO6 (SWO) adsorbing 97% of the MB dye followed by photocatalytic degradation of almost 64% of the remaining dye in 80 min. Furthermore, using different dyes, it is concluded that Ru–SWO showcases high adsorption toward the cationic dyes while it neither adsorbs the anionic dye nor displays photocatalytic degradation. [ABSTRACT FROM AUTHOR]

The disorder‐to‐order (crystallization) process in phase‐change materials determines the speed and storage polymorphism of phase‐change memory devices. Only by clarifying the fine‐structure variation can the devices be insightfully designed, and encode and store information. As essential phase‐change parent materials, the crystallized Sb–Te binary system is generally considered to have the cationic/anionic site occupied by Sb/Te atoms. Here, direct atomic identification and simulation demonstrate that the ultrafast crystallization speed of Sb–Te materials is due to the random nature of lattice site occupation by different classes of atoms with the resulting octahedral motifs having high similarity to the amorphous state. It is further proved that after atomic ordering with disordered chemical occupation, chemical ordering takes place, which results in different storage states with different resistance values. These new insights into the complicated route from disorder to order will play an essential role in designing neuromorphic devices with varying polymorphisms. [ABSTRACT FROM AUTHOR]

In this work, the origins of the inhomogeneous field within the HfO2-based ferroelectric (FE) capacitor are investigated. We propose a model to simulate the relationship between the reversed polarization and the applied pulses with different amplitudes and durations. The electric field distribution is considered to be influenced by the ferroelectric layer thickness (tFE) and the built-in field (Eb). Then, the distribution parameters of both two physical factors and the Merz law, which define the switching dynamics, could be obtained by fitting the experimental results. Comparing with the results of high-resolution transmission electron microscope and first-order reversal curve measurements, it can be reasonably concluded that the physical origin of the inhomogeneous field in HfO2-based ferroelectrics is the random distribution of tFE and Eb. This work improves the understanding of the switching dynamics by providing the origins of the inhomogeneous field in an FE film. [ABSTRACT FROM AUTHOR]

Interface of core-shell Co-CoO nanostructure exhibits exchange bias (EB) phenomenon which arises due to the competition between ferromagnetic (FM) and antiferromagnetic (AFM) order at the interface. Here, in this manuscript, we study core-shell Co-CoO nanostructure and report an approach for tuning the EB field ( H E ) and coercivity ( H C ) via controlling interparticle separation which leads to variable interactions. The core-shell Co-CoO structure has been prepared in a conventional sol-gel route. Further, a variable amorphous non-magnetic silica (SiO 2 ) shell is coated over the nanoparticles via typical chemical synthesis to control the interparticle interaction. Analysis of powder X-ray diffraction (PXRD) data and transmission electron microscope (TEM) images confirms creation of SiO 2 -coated Co-CoO with average particle size ≈ 18 nm. Studies on isothermal remanence magnetization (IRM) and dc demagnetization (DCD) indicate that the dipolar interaction among the nanoparticles varies inversely with interparticle separation. With increase in SiO 2 coating thickness, i.e., decrease in interparticle interactions, H E and H C decrease monotonically. These results open up the possibility of tuning EB by controlling interparticle interactions. [ABSTRACT FROM AUTHOR]

Sulfur dioxide (SO2), a novel endogenous gas signaling molecule, is involved in the regulation of cardiac function. Exerting a key role in progression of hyperthyroidism-induced cardiomyopathy (HTC), myocardial fibrosis is mainly caused by myocardial apoptosis, leading to poor treatment outcomes and prognoses. This study aimed to investigate the effect of SO2 on the hyperthyroidism-induced myocardial fibrosis and the underlying regulatory mechanisms. Elisa, Masson staining, Western-Blot, transmission electron microscope, and immunofluorescence were employed to evaluate the myocardial interstitial collagen deposition, endoplasmic reticulum stress (ERS), apoptosis, changes in endogenous SO2, and Hippo pathways from in vitro and in vivo experiments. The study results indicated that the hyperthyroidism-induced myocardial fibrosis was accompanied by decreased cardiac function, and down-regulated ERS, apoptosis, and endogenous SO2-producing enzyme aspartate aminotransferase (AAT)1/2 in cardiac myocytes. In contrast, exogenous SO2 donors improved cardiac function, reduced myocardial interstitial collagen deposition, up-regulated AAT1/2, antagonized ERS and apoptosis, and inhibited excessive activation of Hippo pathway in hyperthyroid rats. In conclusion, the results herein suggested that SO2 inhibited the overactivation of the Hippo pathway, antagonized ERS and apoptosis, and alleviated myocardial fibrosis in hyperthyroid rats. Therefore, this study was expected to identify intervention targets and new strategies for prevention and treatment of HTC. [ABSTRACT FROM AUTHOR]