Electron microscopy

BACKGROUND: As polyether ether ketone (PEEK) is a relatively new material in dentistry, its bonding properties with regard to dental acrylic base materials are not fully known. To ensure the long-term success of removable dentures with a PEEK framework, the base materials must be well bonded to each other. OBJECTIVES: The study aimed to investigate the effects of different kinds of surface roughening treatment on PEEK and acrylic resin bonding. MATERIAL AND METHODS: Eighty PEEK specimens (N = 80) were randomly divided into 5 groups (n = 16 per group) and subjected to various surface roughening treatment (control, grinding, sandblasting, tribochemical silica coating (CoJet), and sulfuric acid etching)...

Grain boundaries (GBs) and twin boundaries (TBs) in copper (Cu) are two major planar defects that influence electrical conductivity due to their complex electron transport characteristics, involving electron scattering and electron concentration. Understanding their local electronic states is crucial for the design of future conductor materials. In this study, we characterized electron behaviors at TBs and GBs within one Cu grain using atomic force microscopy. Our findings revealed that, compared with GBs, TBs exhibit better current transport capability (direct-current mode) and larger electromagnetic loss (high-frequency microwave mode)...

BACKGROUND: Radiofrequency (RF)-based devices are frequently used in plastic surgeries. In the current literature, no comparative experimental study has demonstrated the histological and immunological effects of these devices that are frequently used in the facial area. In this study, we investigated the histological and immunological effects of Bipolar RF (BodyTite) and Microneedle RF (Morpheus 8) devices in the rat abdominal region. METHODS: 24 rats were used in this study...

Titanium (Ti) implants are widely used in orthopedic and dental applications due to their excellent biocompatibility and mechanical properties. However, bacterial adhesion and subsequent biofilm formation on implant surfaces pose a significant risk of postoperative infections and complications. Conventional surface modifications often lack long-lasting antibacterial efficacy, necessitating the development of novel coatings with enhanced antimicrobial properties. This study aims to develop a novel Ag-TiO2 -OTS (Silver-Titanium dioxide-Octadecyltrichlorosilane, ATO) nanocomposite coating, through a chemical plating method...

The chemical and pore structures of coal play a crucial role in determining the content of free gas in coal reservoirs. This study focuses on investigating the impact of acidification transformation on the micro-physical and chemical structure characteristics of coal samples collected from Wenjiaba No. 1 Mine in Guizhou. The research involves a semi-quantitative analysis of the chemical structure parameters and crystal structure of coal samples before and after acidification using Fourier Transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) experiments...

Cyanobacteria, red algae, and cryptophytes produce two classes of proteins for light-harvesting: water-soluble phycobiliproteins and membrane-intrinsic proteins that bind chlorophylls and carotenoids. In cyanobacteria, red algae, and glaucophytes, phycobilisomes (PBS) are complexes of brightly colored phycobiliproteins and linker (assembly) proteins. To date, six structural classes of phycobilisomes have been described: hemiellipsoidal, block-shaped, hemidiscoidal, bundle-shaped, paddle-shaped, and far-red-light bicylindrical...

OBJECTIVE: To investigate the mechanism of induction of ferroptosis by brazilin in breast cancer cells. METHODS: Breast cancer 4T1 cells were divided into 6 groups: control, brazilin 1/2 half maximal inhibitory concentration (IC50 ), IC50 , 2×IC50 , erastin (10 µg/mL) and capecitabine (10 µg/mL) groups. The effect of brazilin on the proliferation of 4T1 cells was detected by cell counting kit-8 assay, and the treatment dose of brazilin was screened...

Elemental surface segregation in cathode materials is critical for determining the phase and interfacial reaction between the electrode and electrolyte, which consequently affects the electrochemical properties. Single-crystal cathodes of Li1.2 Ni0.2 Mn0.6 O2 and Li1.2 Ni0.2 Mn0.6 O1.95 F0.05 with octahedral morphologies of (102)- and (003)-dominated facets have been manifested to show enhanced electrochemical properties. However, the surface structural features of such single crystals have not been investigated...

UNLABELLED: Due to fungal diseases that threaten immunocompromised patients, along with the limited availability of antifungal agents, there is an urgent need for new antifungal compounds to treat fungal infections. Here, we aimed to identify potential antifungal drugs from natural products using the fission yeast Schizosaccharomyces pombe as a model organism since it shares many features with some pathogenic fungi. Here, we identified tubeimoside I (TBMS1), an extract from Chinese herbal medicine, that showed strong antifungal activity against S...

UNLABELLED: Antimicrobial resistance (AMR) poses a significant worldwide public health crisis that continues to threaten our ability to successfully treat bacterial infections. With the decline in effectiveness of conventional antimicrobial therapies and the lack of new antibiotic pipelines, there is a renewed interest in exploring the potential of metal-based antimicrobial compounds. Antimony-based compounds with a long history of use in medicine have re-emerged as potential antimicrobial agents...

Evaluating the heterogeneity of extracellular vesicles (EVs) is crucial for unraveling their complex actions and biodistribution. Here, we identify consistent architectural heterogeneity of EVs using cryogenic transmission electron microscopy (cryo-TEM), which has an inherent ability to image biological samples without harsh labeling methods while preserving their native conformation. Imaging EVs isolated using different methodologies from distinct sources, such as cancer cells, normal cells, immortalized cells, and body fluids, we identify a structural atlas of their dominantly consistent shapes...

Brevibacillus thermoruber strain Nabari cells grow as widely spreading dendritic colonies on reasoner's 2A-agar (1.5%) plates at around 55°C but as small motile colonies at 37°C. Motile colonies can be divided into colonies that move in straight or curved lines over long distances (wandering colonies), and colonies that rotate at a fixed location (rotating colonies). The addition of surfactant to the agar medium greatly increased the frequency of wandering colonies and facilitated the study of such colonies...

The feeding habits and habitats of fish influence the morphology of the oral cavity. This study used gross anatomy, light microscopy, and scanning electron microscopy, in addition to morphometric analysis, to investigate the anatomical characteristics of the oral cavity roof in Pagrus pagrus and Boops boops, which have different dietary habits. The oral cavity roof appeared U-shaped and divided into the palate and upper pharyngeal regions. The upper lip of P. pagrus was broad, while B. boops' upper lip was small and thin...

Scandium oxide (Sc2 O3 ) has a wide range of applications in metallurgy, chemical industry, electronics and many other high-tech fields. However, most Sc2 O3 materials exist in the powder or bulk form, while nanostructured Sc2 O3 has rarely been reported as there is a lack of a common method to control its dimensionality, hindering the understanding of new properties and potential applications of nano-Sc2 O3 materials. In this paper, we establish a procedure to synthesize a two-dimensional (2D) Sc2 O3 -covalent organic framework (COF) composite film where the crystal size of Sc2 O3 domains is as small as ∼3 nm...

Corrosion protection of metal has become an important and urgent topic, which requires the development of an inexpensive, environmentally friendly, and highly efficient corrosion inhibitor. Herein, a sweet potato leaf extract (SPL) was obtained by a simple water-based extraction method and then as a green corrosion inhibitor for 6N01 Al alloy in the seawater was well investigated by the weight loss method and various electrochemical tests. Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-vis) spectroscopies were carried out to investigate the compositions of SPL...

The present work reports the rapid sweat detection inside a PPE kit using a flexible humidity sensor based on hydrothermally synthesized ZnO (zinc oxide) nanoflowers (ZNFs). Physical characterization of ZNFs was done using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), UV-visible, particle size analysis, Raman analysis, and X-ray photoelectron spectroscopy (XPS) analysis, and the hydrophilicity was investigated by using contact angle measurement...

Studies have shown that poly(adenine) DNA and RNA strands protonate at a low pH to form self-associating duplexes; however, the nanoscopic morphology of these structures is unclear. Here, we use Transition Electron Microscopy (TEM), Atomic Force Microscopy (AFM), dynamic light scattering (DLS), and fluorescence spectroscopy to show that both ribose identity (DNA or RNA) and assembly conditions (thermal or room-temperature annealing) dictate unique hierarchical structures for poly(adenine) sequences at a low pH...

We study the origin of bimodal emission in AlGaN/AlN QD superlattices displaying a high internal quantum efficiency (around 50%) in the 230-300 nm spectral range. The secondary emission at longer wavelengths is linked to the presence of cone-like domains with deformed QD layers, which originate at the first AlN buffer/superlattice interface and propagate vertically. The cones originate at a 30°-faceted shallow pit in the AlN, which appears to be associated with a threading dislocation that produces strong shear strain...

A novel noncovalent surface modification of commercial single-walled carbon nanotubes (SWCNTs) was successfully carried out by using ball grinding technology between SWCNTs and mixed dispersants (polyvinylpyrrolidone (PVP) and alkanolamine), affording a highly homogeneous and stable PA-SWCNTs dispersion in water. The homogeneous dispersibility and long storage stability were systematically investigated by transmittance spectroscopy, absorption spectroscopy, zeta potential analyzer, sedimentation photo and transmittance electron microscopy...

In monocrystalline Si (c-Si) solar cells, identification and mitigation of bulk defects are crucial to achieving a high photoconversion efficiency. To spectroscopically detect defects in the c-Si bulk, it is desirable to passivate the surface defects. Passivation of the c-Si surface with dielectrics such as Al2 O3 and SiN x requires deposition at elevated temperatures, which can influence defects in the bulk. Herein, we report on the passivation of different Czochralski (Cz) Si wafer surfaces by an organic copolymer, Nafion...