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Hemp and its composites are becoming increasingly popular for their environmental benefits and mechanical strength, making them critical in the development of sustainable materials. This study investigated the nanomechanical properties of industrial hemp fibers through the application of Atomic Force Microscopy (AFM). An AFM-based examination of individual fibers allows for the accurate assessment of nanoscale characteristics without interference from extraneous particles, providing a clear insight into individual fiber features. Using Sneddon's analytical model for a paraboloid shape AFM tip geometry, the elastic moduli of the hemp fiber were calculated at different indentation depths. The maximum elastic modulus of 3.01 ± 0.22 GPa was observed at the lowest indentation depth. These findings demonstrated the mechanical nature of hemp fibers, showing that radial measures deviate significantly from longitudinal measurements commonly reported in the literature. [ABSTRACT FROM AUTHOR]

We investigated the stability of monolayer MoS2 samples synthesized using chemical vapor deposition and subsequently modified with organic molecules under ambient conditions. By analyzing the optical signatures of the samples using photoluminescence spectroscopy, Raman spectroscopy, and surface quality using atomic force microscopy, we observed that this modification of monolayer MoS2 with organic molecules is stable and retains its optical signature over time under ambient conditions. Furthermore, we show the reversibility of the effects induced by the organic molecules, as heating the modified samples restores their original optical signatures, indicating the re-establishment of the optical properties of the pristine monolayer MoS2. [ABSTRACT FROM AUTHOR]

We investigated the stability of monolayer MoS2 samples synthesized using chemical vapor deposition and subsequently modified with organic molecules under ambient conditions. By analyzing the optical signatures of the samples using photoluminescence spectroscopy, Raman spectroscopy, and surface quality using atomic force microscopy, we observed that this modification of monolayer MoS2 with organic molecules is stable and retains its optical signature over time under ambient conditions. Furthermore, we show the reversibility of the effects induced by the organic molecules, as heating the modified samples restores their original optical signatures, indicating the re-establishment of the optical properties of the pristine monolayer MoS2. [ABSTRACT FROM AUTHOR]

Recent advances in the clinical extracellular vesicles (EVs) field highlight their potential as biomarkers for diverse diseases and therapeutic applications. This study provides an in-depth characterization of 10k EVs from human microvascular endothelial cells (HMEC-1) exposed to benzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon found in food and smoke. Given EVs' complexity, with numerous surface and cargo proteins, phenotyping remains challenging. Here, we introduce a multiplex biosensor, in µarray format, for profiling EVs from distinct cellular conditions, employing a multimodal approach that combines surface plasmon resonance imaging (SPRi) and in situ atomic force microscopy (AFM) to decipher EVs' biochemical and biophysical properties. SPRi experiments showed notable EV capture differences on ligands such as Anti-CD36, Anti-CD81, and Anti-ApoA between treated and control conditions, likely due to B[a]P exposure. A complementary AFM study and statistical analyses revealed size differences between EVs from treated and control samples, with ligands like Annexin-V, Anti-CD36, and Anti-VEGFR1 emerging as ligands specific to potential cytotoxicity biomarkers. Our findings suggest that B[a]P exposure may increase EV size and alter marker expression, indicating phenotypic shifts in EVs under cytotoxic stress. The original combination of SPRi and AFM reveals valuable data on the phenotypical and morphological heterogeneities of EV subsets linked to cytotoxic stresses and highlights the potential of EVs as specific toxicological markers. [ABSTRACT FROM AUTHOR]

The concept and feasibility of producing liposomes by rehydrating engineered lipid nanoconstructs are demonstrated in this study. Nanoconstructs of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were produced using a microfluidic delivery probe integrated with an atomic force microscope. The subsequent rehydration of these POPC constructs led to the formation of liposomes, most of which remained adhered to the surface. The size (e.g., diameter) of the liposomes could be tuned by varying the lateral dimension of the lipid constructs. Hierarchical liposomal structures, such as pentagons containing five liposomes at the corners, could also be designed and produced by depositing lipid constructs to designated locations on the surfaces, followed by rehydration. This new means allows for regulating liposomal sizes, distributions, and compositions. The outcomes benefit applications of liposomes as delivery vehicles, sensors, and building blocks in biomaterials design. The ability to produce hierarchical liposomal structures benefits numerous applications such as proto-cell development, multiplexed bio-composite materials, and the engineering of local bio-environments. [ABSTRACT FROM AUTHOR]

Biocomposite filaments for material extrusion (MEX) additive manufacturing, particularly those derived from agricultural biomass, have attracted significant research and industrial interest. Biochar is a well-documented reinforcement agent that is used in several polymeric matrices. However, systematic research efforts regarding the quality scores of parts built with MEX 3D printing with biochar-based filaments are marginal. Herein, the impact of biochar loading on the quality metrics of the five most popular polymers for MEX 3D printing (ABS, HDPE, PETG, PP, and PLA) is quantitatively examined in depth. Sophisticated and massive Non-Destructive Tests (NDTs) were conducted, and the impact of biochar loading on the critical quality indicators (CQIs), including porosity, dimensional conformity, and surface roughness, was documented. The quality scores for the biochar filler loading, also five in total, were statistically correlated with the corresponding reinforcement metrics for the five polymeric matrices. A statistically significant antagonistic interaction between the tensile strength course and porosity/dimensional deviation metrics, particularly for PETG, was observed. It can be concluded that the lowest porosity and dimensional deviation are associated with the highest strength. The 4 wt% biocomposite exhibited optimal quality performance in most polymers studied. Highlights: Comparison of the effects of biochar on five polymeric matrices in additive manufacturing: Acrylonitrile Butadiene Styrene (ABS), High Density Polyethylene (HDPE), Polyethylene Terephthalate Glycol (PETG), Polypropylene (PP), and Polylactic Acid (PLA). Quality metrics (surface roughness, porosity, and dimensional accuracy) were compared and correlated with mechanical response. Low porosities and dimensional deviations were detected in the 4 wt% polymer/biochar composites, having the highest tensile strength among the composites tested. [ABSTRACT FROM AUTHOR]

In eukaryotic nuclei, DNA is wrapped around an octamer of core histones to form nucleosomes. H1 binds to the linker DNA of nucleosome to form the chromatosome, the next structural unit of chromatin. Structural features on individual chromatosomes contribute to chromatin structure, but not fully characterized. In addition to canonical nucleosomes composed of two copies each of histones H2A, H2B, H3, and H4 (H3 nucleosomes), centromeres chromatin contain nucleosomes in which H3 is replaced with its analog CENP-A, changing structural properties of CENP-A nucleosomes. Nothing is known about the interaction of H1 with CENP-A nucleosomes. Here we filled this gap and characterized the interaction of H1 histone with both types of nucleosomes. H1 does bind both types of the nucleosomes forming more compact chromosome particles with elevated affinity to H3 nucleosomes. H1 binding significantly increases the stability of chromatosomes preventing their spontaneous dissociation. In addition to binding to the entry-exit position of the DNA arms identified earlier, H1 is capable of bridging of distant DNA segments. H1 binding leads to the assembly of mononucleosomes in aggregates, stabilized by internucleosome interactions as well as bridging of the DNA arms of chromatosomes. Contribution of these finding to the chromatin structure and functions are discussed. [ABSTRACT FROM AUTHOR]

Biomacromolecules generally exist and function in aqueous media. Is it possible to estimate the state and properties of molecules in an initial three-dimensional colloidal solution based on the structure properties of biomolecules adsorbed on the two-dimensional surface? Using atomic force microscopy to study nanosized objects requires their immobilization on a surface. Particles undergoing Brownian motion in a solution significantly reduce their velocity near the surface and become completely immobilized upon drying. Using radial distribution function (RDF) methods, it is possible to obtain information about the presence of short-range or long-range order in the arrangement of immobilized colloidal particles. In this work, RDF is applied to immobilized gold nanoparticles (AuNPs) and horseradish peroxidase molecules on mica. It is shown that AuNPs maintain mobility on the mica surface when water is present. Upon immobilization, AuNPs organize into an amorphous structure exhibiting short-range order. Protein molecules are immobilized randomly, and their surface density is well described by the Poisson distribution. [ABSTRACT FROM AUTHOR]

The drive for the development of systems that can simultaneously investigate chemical and morphological information comes from the requisite to fully understand the structure and chemical reactivity relationships of materials. This is particularly relevant in photocatalysis, a field ruled by surface interactions. An in-depth understanding of these complex interactions could lead to significant improvements in materials design, and consequently, in photocatalytic performances. Here, we present a first approach to a combined atomic force microscopy (AFM) and Raman spectroscopy characterization of anodic TiO2 nanotubes arrays decorated with Ag nanoparticle electrodeposition from either the same anodizing organic electrolyte or from an aqueous one. Photocatalytic substrates were used in up to 15 consecutive photocatalysis tests to prove their possible deterioration with reuse. Sample aging can, in principle, produce changes in both the morphology and the chemical compounds that characterize the photocatalyst surface. Adopting multiple characterization techniques, such as a combination of AFM and Raman spectroscopy in an original setup, can profitably enable the observation of surface contamination. A significant drop in photocatalytic activity was observed after 10 cycles on samples where silver was deposited from the organic electrolyte, while the others remained stable. Such a drop was ascribed to photocatalyst deactivation. While in other cases, a simple recovery treatment allowed the initial photoactivity to be restored, this deactivation was not restored even after chemical and thermal cleaning treatments.

Nanofibers can be produced by various techniques, such as a broad range of electrospinning techniques to produce nanofiber mats from different polymers or polymer blends, often filled with metallic or semiconducting nanoparticles or by different nanotechnological bottom-up or top-down methods. They are important parts of a wide variety of energy applications, such as batteries, fuel cells, photovoltaics, or hydrogen storage materials. Usually, their physical or chemical parameters are measured by averaging over a fiber bundle or a part of a nanofiber mat. Here, we report the possibility of measuring the different physical and chemical properties of single nanofibers and nanowires. Such measurements of single nanofiber properties are more complicated than investigations of fiber bundles or whole nanofiber mats and, thus, are less often found in the literature. After a fast increase in such investigations between 2001 and 2009, the numbers of respective studies are now stagnating. This review thus aims to make the different possibilities more visible to a broader scientific audience by providing several examples based on atomic force microscopy (AFM) and other broadly available techniques. The focus of this review is on technologies that reveal more information than the pure surface morphology of nanofibers or nanowires, such as mechanical properties or wettability, porosity, or electrical conductivity.

The constructs of lipid molecules follow self-assembly, driven by intermolecular interactions, forming stacking of lipid bilayer films. Achieving designed geometry at nano- to micro-levels with packing deviating from the near-equilibrium structure is difficult to achieve due to the strong tendency of lipid molecules to self-assemble. Using ultrasmall (sn-glycero-3-phosphocholine (POPC). Taking advantage of the high spatial precision and the minute size of the delivery probe in our combined atomic force microscopy and microfluidic delivery, the transient shape of each liquid droplet is regulated. In doing so, the final geometry of the POPC assemblies has been regulated to the designed geometry with nanometer precision. The results extend the concept of controlled assembly of molecules to amphiphilic systems. The outcomes exhibit high potential in lipid-based biomaterial science and biodevice engineering.

In the present work dwarf palm leaf extract (DPLE) has been prepared to be used as a corrosion inhibitor on carbon steel in a saline medium. The inhibitory efficiency of DPLE on the corrosion rate of carbon XC70 steel (CS) in a 3.5% NaCl solution has been studied by means of weight loss measurements, potentiodynamic polarization curves, electrochemical impedance spectroscopy, SEM and AFM microscopies. The results showed that the corrosion inhibition rate of carbon XC70 steel in the NaCl solution increases with the concentration of DPLE, and reaches up to 90% at 2.0 ⋅ 10 − 4 g. L − 1 2.0 ⋅ 10 − 4 g. L − 1 as the optimum concentration of DPLE. The inhibiting performance against corrosion was attributed to the formation a DPLE barrier that reduces the contact area between the carbon XC70 steel and the corrosive solution. The EIS analysis revealed that the presence of DPLE was found to decrease the double layer capacitance, with an increasing charge transfer resistance. The morphological analysis showed that upon adding DPLE in saline solution, the surface morphology of the metal becomes smoother due to the formation a protective layer adsorbed on the metal surface. This study showed that dwarf palm leaf extract acts as an efficient and eco-friendly inhibitor on carbon steel in saline medium. [ABSTRACT FROM AUTHOR]

We investigated stress fiber formation induced by photodynamic therapy (PDT) with porphylipoprotein (PLP) by observing actin filaments by super-resolution confocal microscopy and measuring the cellular elastic modulus by atomic force microscopy. We identified different intracellular mechanisms of stress fiber formation between RGM1 epithelial cells, which were derived from rat gastric mucosa, and RGK1 cells, which were cancer-like mutants of RGM1. Our findings show that when PLP is used as a photosensitizer in PDT, it selectively induces necrosis in tumors with minimal impact on the surrounding normal tissues, as it is less likely to cause blood flow obstruction. [ABSTRACT FROM AUTHOR]

This review is focused on the bee structure observed by atomic force microscopy (AFM). For more than 20 years, the chemical origin and formation mechanism of the bee structure have been studied with the aid of AFM, resulting in numerous perspectives and controversies. Specifically, two dominant views dominate the debate on the chemical origin of bee structures. Some scholars tend to believe that the chemical composition of the bee structure is highly related to wax, while others consider that it is related to asphaltenes. In recent years, it has been acknowledged that the bee structure solely pertains to the microstructure on the surface of bitumen rather than its internal structure. The formation mechanism of the bee structure is elucidated by introducing the surface wrinkling theory of multilayer composites from the field of elastic-viscoelastic material. Based on the investigation of articles, this review concludes that the bee structure is more likely the wax crystallisation and surface wrinkling, and there exist certain specific correlations between the morphology of bee structures and macroscopic properties of bitumen. Furthermore, it is recommended that the bitumen research community adopt a standardised and simplified sample preparation procedure to enhance experimental comparability. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials are potential candidates for electronic devices due to their unique structures and exceptional physical properties, making them a focal point in nanotechnology research. Accurate assessment of the mechanical and tribological properties of 2D materials is imperative to fully exploit their potential across diverse applications. However, their nanoscale thickness and planar nature pose significant challenges in testing and characterizing their mechanical properties. Among the in situ characterization techniques, atomic force microscopy (AFM) has gained widespread applications in exploring the mechanical behaviour of nanomaterials, because of the easy measurement capability of nano force and displacement from the AFM tips. Specifically, AFM-based force spectroscopy is a common approach for studying the mechanical and tribological properties of 2D materials. This review comprehensively details the methods based on normal force spectroscopy, which are utilized to test and characterize the elastic and fracture properties, adhesion, and fatigue of 2D materials. Additionally, the methods using lateral force spectroscopy can characterize the interfacial properties of 2D materials, including surface friction of 2D materials, shear behaviour of interlayers as well as nanoflake-substrate interfaces. The influence of various factors, such as testing methods, external environments, and the properties of test samples, on the measured mechanical properties is also addressed. In the end, the current challenges and issues in AFM-based measurements of mechanical and tribological properties of 2D materials are discussed, which identifies the trend in the combination of multiple methods concerning the future development of the in situ testing techniques. [ABSTRACT FROM AUTHOR]

Nanofibers can be produced by various techniques, such as a broad range of electrospinning techniques to produce nanofiber mats from different polymers or polymer blends, often filled with metallic or semiconducting nanoparticles or by different nanotechnological bottom-up or top-down methods. They are important parts of a wide variety of energy applications, such as batteries, fuel cells, photovoltaics, or hydrogen storage materials. Usually, their physical or chemical parameters are measured by averaging over a fiber bundle or a part of a nanofiber mat. Here, we report the possibility of measuring the different physical and chemical properties of single nanofibers and nanowires. Such measurements of single nanofiber properties are more complicated than investigations of fiber bundles or whole nanofiber mats and, thus, are less often found in the literature. After a fast increase in such investigations between 2001 and 2009, the numbers of respective studies are now stagnating. This review thus aims to make the different possibilities more visible to a broader scientific audience by providing several examples based on atomic force microscopy (AFM) and other broadly available techniques. The focus of this review is on technologies that reveal more information than the pure surface morphology of nanofibers or nanowires, such as mechanical properties or wettability, porosity, or electrical conductivity. [ABSTRACT FROM AUTHOR]

The drive for the development of systems that can simultaneously investigate chemical and morphological information comes from the requisite to fully understand the structure and chemical reactivity relationships of materials. This is particularly relevant in photocatalysis, a field ruled by surface interactions. An in-depth understanding of these complex interactions could lead to significant improvements in materials design, and consequently, in photocatalytic performances. Here, we present a first approach to a combined atomic force microscopy (AFM) and Raman spectroscopy characterization of anodic TiO2 nanotubes arrays decorated with Ag nanoparticle electrodeposition from either the same anodizing organic electrolyte or from an aqueous one. Photocatalytic substrates were used in up to 15 consecutive photocatalysis tests to prove their possible deterioration with reuse. Sample aging can, in principle, produce changes in both the morphology and the chemical compounds that characterize the photocatalyst surface. Adopting multiple characterization techniques, such as a combination of AFM and Raman spectroscopy in an original setup, can profitably enable the observation of surface contamination. A significant drop in photocatalytic activity was observed after 10 cycles on samples where silver was deposited from the organic electrolyte, while the others remained stable. Such a drop was ascribed to photocatalyst deactivation. While in other cases, a simple recovery treatment allowed the initial photoactivity to be restored, this deactivation was not restored even after chemical and thermal cleaning treatments. [ABSTRACT FROM AUTHOR]

Nanomaterials hold great significance in fields such as physical, chemistry, and semiconductors. Atomic Force Microscopy (AFM), a widely employed tool for characterizing the surface morphology of nanoscale materials, suffers from a time-consuming imaging process due to its raster scanning method. To accelerate AFM imaging, we proposed an AFM super-resolution imaging method that reconstructs low-resolution AFM images into high-resolution ones, enhancing the AFM imaging speed by 3.5–7.5 times while ensuring imaging quality. We introduced a More Rational Transformer (MRT) as the super-resolution reconstruction neural network. This network enhances the attention mechanism of the Transformer and dynamically integrates the attention mechanism with a depth-wise convolution (DW-Conv), thus better adapting to the processing of AFM images of nanoscale materials. After training and testing on a data set containing common materials and devices for integrated circuits, our method demonstrates superior imaging quality compared to other super-resolution imaging methods. In general, our method is an effective way to accelerate the characterization of nanomaterials. [ABSTRACT FROM AUTHOR]

PEF technology is a non-thermal food process gaining popularity for treating fruits and vegetables. However, there has been little investigation into the impact of PEF on the biomolecular components of plant tissues. This study assesses the influence of PEF at low (1.5 kJ/kg) and medium (151 kJ/kg) intensities on the physicochemical parameters of pectin fractions isolated from green and red tomatoes. Monopolar exponential decay pulses of 1.0 and 10.0 kV/cm were delivered to alcohol-insoluble residue (AIR) recovered from mature green and ripe red tomatoes. Topography and recognition imaging were performed using atomic force microscopy (AFM) on three pectin fractions: water-soluble pectin (WSP), chelator-soluble pectin (CSP), and diluted alkali-soluble pectin (DASP). Image analysis has been used to characterize the geometrical properties of pectin. PEF treatments generated considerable structural alterations in all pectin fractions. The effect varied depending on the stage of tomato ripening and the energy input applied. The average length of WSP fibres in red tomatoes decreased dramatically (up to 50% shorter) as the intensity of the electric field increased. Green tomatoes showed the opposite effect, with the length of the WSP fibres increasing as the applied electric field increased. The monosaccharide composition revealed that PEF decreased pectin linearity independent of the fruit ripening stage. The data obtained on PEF-pectin interactions might assist in building tailored food processes that rely on pectin's functional qualities and a better understanding of the effect of the ripening stage on PEF efficacy. [ABSTRACT FROM AUTHOR]

Atomic force microscopy (AFM) is a kind of high‐precision instrument to measure the surface morphology of various conductive or nonconductive samples. However, obtaining a high‐resolution image with standard AFM scanning requires more time. Using block compressive sensing (BCS) is an effective approach to achieve rapid AFM imaging. But, the routine BCS‐AFM imaging is difficult to balance the image quality of each local area. It is easy to lead to excessive sampling in some flat areas, resulting in time‐consuming. At the same time, there is a lack of sampling in some areas with significant details, resulting in poor imaging quality. Thus, an innovative adaptive BCS‐AFM imaging method is proposed. The overlapped block is used to eliminate blocking artifacts. Characteristic parameters (GTV, Lu, and SD) are used to predict the local morphological characteristics of the samples. Back propagation neural network is employed to acquire the appropriate sampling rate of each sub‐block. Sampling points are obtained by pre‐scanning and adaptive supplementary scanning. Afterward, all sub‐block images are reconstructed using the TVAL3 algorithm. Each sample is capable of achieving uniform, excellent image quality. Image visual effects and evaluation indicators (PSNR and SSIM) are employed for the purpose of evaluating and analyzing the imaging effects of samples. Compared with two nonadaptive and two other adaptive imaging schemes, our proposed scheme has the characteristics of a high degree of automation, uniformly high‐quality imaging, and rapid imaging speed. Highlights: The proposed adaptive BCS method can address the issues of uneven image quality and slow imaging speed in AFM.The appropriate sampling rate of each sub‐block of the sample can be obtained by BP neural network.The introduction of GTV, Lu, and SD can effectively reveal the morphological features of AFM images.Seven samples with different morphology are used to test the performance of the proposed adaptive algorithm.Practical experiments are carried out with two samples to verify the feasibility of the proposed adaptive algorithm. [ABSTRACT FROM AUTHOR]

Friction has been considered to mediate physiological activities of cells, however, the biological friction between a single cell and its ligand-bound surface has not been thoroughly explored. Herein, we established a friction model for single cells based on an atomic force microscopy (AFM) combined with an inverted fluorescence microscopy (IFM) to study the friction between a highly sensitive platelet and fibrinogen-coated surface. The study revealed that the friction between the platelet and fibrinogen-coated tip is mainly influenced by specific ligand–receptor interaction. Further, we modeled the biological friction, which consists of specific interaction, non-specific interaction, and mechanical effect. Besides, the results suggested that the velocity can also affect specific ligand–receptor interactions, resulting in the friction change and platelet adhesion to fibrinogen surfaces. The study built a friction model between a single cell and its ligand-bound surface and provided a potential method to study the biological friction by the combination of AFM and IFM. [ABSTRACT FROM AUTHOR]

The mechanical properties of single flax fibers are characterized here as a function of dew retting. The fibers are measured using micromechanical and nanomechanical techniques over a large retting period (91 days). Damage-free single flax fibers in various stages of dew retting were manually extracted from retted flax plant stems. The flexural modulus and strength of the flax fibers were determined using micromechanical methods. The effective modulus of the outer surface of the single fibers was measured using AFM-based nanoindentation. The micromechanical methods revealed that the flexural modulus and strength of the manually extracted single fibers does not vary significantly as the retting progresses. The micromechanical methods revealed two distinct values of flexural strength in the fibers attributed to different failure modes. The values of these strengths do not vary significantly with retting or over-retting. The nanomechanical methods revealed that the effective modulus of the outer surface of the single fibers does evolve with retting. The physical/chemical origin of these observations remains to be established and could be the objective of future work. [ABSTRACT FROM AUTHOR]

The constructs of lipid molecules follow self-assembly, driven by intermolecular interactions, forming stacking of lipid bilayer films. Achieving designed geometry at nano- to micro-levels with packing deviating from the near-equilibrium structure is difficult to achieve due to the strong tendency of lipid molecules to self-assemble. Using ultrasmall (

Abstract Antimicrobial potential of bioactive glass (BAG) makes it promising for implant applications, specifically overcoming the toxicity concerns associated with traditional antibacterial nanoparticles. The 58S composition of BAG (with high Ca and absence of Na) has been known to exhibit excellent bioactivity and antibacterial behaviour, but the mechanisms behind have not been investigated in detail. In this pioneering study, we are using Atomic Force Microscopy (AFM) to gain insights into 58S BAG’s adhesive interactions with planktonic cells of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria; along with the impact of crystallinity on antibacterial properties. We have recorded greater bacterial inhibition by amorphous BAG compared to semi-crystalline glass–ceramics and stronger effect against gram-negative bacteria via conventional long-term antibacterial tests. AFM force distance curves has illustrated substantial bonding between bacteria and BAG within the initial one second (observed at a gap of 250 ms) of contact, with multiple binding events. Further, stronger adhesion of BAG with E.coli (~ 6 nN) compared to S. aureus (~ 3 nN) has been found which can be attributed to more adhesive nano-domains (size effect) distributed uniformly on E.coli surface. This study has revealed direct evidence of impact of contact time and 58S BAG’s crystalline phase on bacterial adhesion and antimicrobial behaviour. Current study has successfully demonstrated the mode and mechanisms of initial bacterial adhesion with 58S BAG. The outcome can pave the way towards improving the designing of implant surfaces for a range of biomedical applications.

Abstract Background Rose flowers contain active ingredients such as flavonoids and volatile oils and are acknowledged to be good natural resources owing to their anti-aging and antioxidant properties. In this study, we develop four new rose varieties (named Ever-rose) that are fragrant, pest resistant, and easy to grow. Subsequently, we evaluate the properties of Ever-rose and its potential for use in anti-aging products. Methods The chemical composition of Ever-rose was determined using ultra-high-performance liquid chromatography triple time-of-flight mass spectrometry/mass spectrometry. The antioxidant activity of the Ever-rose extract was evaluated using various assays, including superoxide dismutase activity, 2,2-diphenyl-1-picrylhydrazyl radical-scavenging capacity, and xanthine oxidase activity. The variations in proteolytic matrix metalloproteinase-1 expression, collagen content after ultraviolet (UV) irradiation, and reactive-oxygen-species (ROS) levels after infrared A (IRA) treatment were evaluated. The variations in cell elasticity were assessed via atomic force microscopy. Results The petal extracts of Ever-rose (named ER004(P), ER011(P), ER012(P), and ER015(P)) showed good antioxidant activity. They effectively inhibited UV irradiation-induced MMP-1 expression and IRA irradiation-induced increase in mitochondrial ROS levels. Additionally, they inhibited variations in cell shape and elasticity as aging progressed. In particular, ER011(P) demonstrated the best anti-aging and antioxidant effects. Conclusion The newly developed Ever-rose showed excellent antioxidant and anti-aging effects. In particular, ER011(P) demonstrated the best properties owing to its high antioxidant content. Hence, it exhibits significant potential as a functional cosmetic ingredient. Graphical Abstract

To comprehensively investigate the impact of chloride salt erosion on the multiscale bonding behavior between asphalt and aggregate, atomic force microscopy (AFM) and pull-off tests were employed. A thorough study was conducted on the microsurface morphology, nanoscale surface roughness, microsurface energy, and macro pull-off strength between asphalt and aggregate under different chloride salt concentrations. Furthermore, the relationship between the microscopic structural characteristics of asphalt and macroscopic bonding performance was analyzed. The results revealed that, except for the crumb rubber (CR) modified asphalt, the surface of asphalt exhibited an alternation of peaks and valleys forming a beelike structure both before and after chloride salt erosion. The erosion caused the reaggregation of asphalt surface particles, resulting in prominent nano-protrusions and white spots, thereby increasing the surface height and roughness of asphalt. In chloride salt solutions, the infiltration of ions and water molecules into the asphalt may lead to irregular depressions and pits on the surface, consequently reducing the surface energy of the asphalt. This further diminished the effective contact area between the asphalt and aggregates, forming microscopic voids and subsequently weakening the bonding strength at the asphalt-aggregate interface. [ABSTRACT FROM AUTHOR]

Antimicrobial potential of bioactive glass (BAG) makes it promising for implant applications, specifically overcoming the toxicity concerns associated with traditional antibacterial nanoparticles. The 58S composition of BAG (with high Ca and absence of Na) has been known to exhibit excellent bioactivity and antibacterial behaviour, but the mechanisms behind have not been investigated in detail. In this pioneering study, we are using Atomic Force Microscopy (AFM) to gain insights into 58S BAG's adhesive interactions with planktonic cells of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria; along with the impact of crystallinity on antibacterial properties. We have recorded greater bacterial inhibition by amorphous BAG compared to semi-crystalline glass–ceramics and stronger effect against gram-negative bacteria via conventional long-term antibacterial tests. AFM force distance curves has illustrated substantial bonding between bacteria and BAG within the initial one second (observed at a gap of 250 ms) of contact, with multiple binding events. Further, stronger adhesion of BAG with E.coli (~ 6 nN) compared to S. aureus (~ 3 nN) has been found which can be attributed to more adhesive nano-domains (size effect) distributed uniformly on E.coli surface. This study has revealed direct evidence of impact of contact time and 58S BAG's crystalline phase on bacterial adhesion and antimicrobial behaviour. Current study has successfully demonstrated the mode and mechanisms of initial bacterial adhesion with 58S BAG. The outcome can pave the way towards improving the designing of implant surfaces for a range of biomedical applications. [ABSTRACT FROM AUTHOR]

Penetrating deep into the cells of the human body in real time has become increasingly possible with the implementation of modern technologies in medicine. Atomic force microscopy (AFM) enables the effective live imaging of cellular and molecular structures of biological samples (such as cells surfaces, components of biological membranes, cell nuclei, actin networks, proteins, and DNA) and provides three-dimensional surface visualization (in X-, Y-, and Z-planes). Furthermore, the AFM technique enables the study of the mechanical, electrical, and magnetic properties of cells and cell organelles and the measurements of interaction forces between biomolecules. The technique has found wide application in cancer research. With the use of AFM, it is not only possible to differentiate between healthy and cancerous cells, but also to distinguish between the stages of cancerous conditions. For many years, AFM has been an important tool for the study of neurodegenerative diseases associated with the deposition of peptide amyloid plaques. In recent years, a significant amount of research has been conducted on the application of AFM in the evaluation of connective tissue cell mechanics. This review aims to provide the spectrum of the most important applications of the AFM technique in medicine to date. [ABSTRACT FROM AUTHOR]

Micro-nano-scale mechanical properties are vital for engineering and biological materials. The elastic modulus is generally measured by processing the force–indentation curves obtained by atomic force microscopy (AFM). However, the measurement precision is largely affected by tip shape, tip wear, sample morphology, and the contact model. In such research, it has been found that the radius of the sharp tip increases due to wear during contact scanning, affecting elastic modulus calculations. For flat-ended tips, it is difficult to identify the contact condition, leading to inaccurate results. Our research team has invented a nano-spherical tip, obtained by implanting focused helium ions into a silicon microcantilever, causing it to expand into a silicon nanosphere. This nano-spherical tip has the advantages of sub-micro size and a smooth spherical surface. Comparative tests of the elastic modulus measurement were conducted on polytetrafluoroethylene (PTFE) and polypropylene (PP) using these three tips. Overall, the experimental results show that our nano-spherical tip with a consistent tip radius, symmetrical geometric shape, and resistance to wear and contamination can improve precision in elastic modulus measurements of polymer materials. [ABSTRACT FROM AUTHOR]

Background: Rose flowers contain active ingredients such as flavonoids and volatile oils and are acknowledged to be good natural resources owing to their anti-aging and antioxidant properties. In this study, we develop four new rose varieties (named Ever-rose) that are fragrant, pest resistant, and easy to grow. Subsequently, we evaluate the properties of Ever-rose and its potential for use in anti-aging products. Methods: The chemical composition of Ever-rose was determined using ultra-high-performance liquid chromatography triple time-of-flight mass spectrometry/mass spectrometry. The antioxidant activity of the Ever-rose extract was evaluated using various assays, including superoxide dismutase activity, 2,2-diphenyl-1-picrylhydrazyl radical-scavenging capacity, and xanthine oxidase activity. The variations in proteolytic matrix metalloproteinase-1 expression, collagen content after ultraviolet (UV) irradiation, and reactive-oxygen-species (ROS) levels after infrared A (IRA) treatment were evaluated. The variations in cell elasticity were assessed via atomic force microscopy. Results: The petal extracts of Ever-rose (named ER004(P), ER011(P), ER012(P), and ER015(P)) showed good antioxidant activity. They effectively inhibited UV irradiation-induced MMP-1 expression and IRA irradiation-induced increase in mitochondrial ROS levels. Additionally, they inhibited variations in cell shape and elasticity as aging progressed. In particular, ER011(P) demonstrated the best anti-aging and antioxidant effects. Conclusion: The newly developed Ever-rose showed excellent antioxidant and anti-aging effects. In particular, ER011(P) demonstrated the best properties owing to its high antioxidant content. Hence, it exhibits significant potential as a functional cosmetic ingredient. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is a highly pathogenic virus responsible for the COVID-19 disease. It belongs to the Coronaviridae family, characterized by a phospholipid envelope, which is crucial for viral entry and replication in host cells. Hypericin, a lipophilic, naturally occurring photosensitizer, was reported to effectively inactivate enveloped viruses, including SARS-CoV-2, upon light irradiation. In addition to its photodynamic activity, Hyp was found to exert an antiviral action also in the dark. This study explores the mechanical properties of heat-inactivated SARS-CoV-2 viral particles using Atomic Force Microscopy (AFM). Results reveal a flexible structure under external stress, potentially contributing to the virus pathogenicity. Although the fixation protocol causes damage to some particles, correlation with fluorescence demonstrates colocalization of partially degraded virions with their genome. The impact of hypericin on the mechanical properties of the virus was assessed and found particularly relevant in dark conditions. These preliminary results suggest that hypericin can affect the mechanical properties of the viral envelope, an effect that warrants further investigation in the context of antiviral therapies. [ABSTRACT FROM AUTHOR]

Silicon has dimensional limitations in following Moore's law; thus, new 2D materials complementing Silicon are being researched. Molybdenum disulfide (MoS2) is a prospective material anticipated to bridge the gap to complement Silicon and enhance the performances of semiconductor devices and embedded systems in the package. For a synthesis process to be of any relevance to the industry. it needs to be at the wafer scale to match existing Silicon wafer-processing standards. Atomic Layer Deposition (ALD) is one of the most promising techniques for synthesizing wafer-scale monolayer MoS2 due to its self-limiting, conformal, and low-temperature characteristics. This paper discusses the wafer-scale ALD synthesis of Molybdenum trioxide (MoO3) using Mo (CO)6 as a precursor with Ozone as a reactant. An ALD-synthesized wafer-scale MoO3 thin film was later sulfurized through Chemical Vapor Deposition (CVD) to transform into stoichiometric MoS2, which was evaluated using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Scanning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). The roles of activation energy and first-order reaction kinetics in determining the ALD recipe parameters of the pulse time, reactor temperature, and purge time are explicitly discussed in detail. Discretized pulsing for developing one-cycle ALD for monolayer growth is suggested. Remedial measures to overcome shortcomings observed during this research are suggested. [ABSTRACT FROM AUTHOR]

[Display omitted] Humic acids (HA) are ubiquitous in surface waters, leading to significant fouling challenges. While zwitterion-like and zwitterionic surfaces have emerged as promising candidates for antifouling, a quantitative understanding of molecular interaction mechanism, particularly at the nanoscale, still remains elusive. In this work, the intermolecular forces between HA and charged, zwitterion-like or zwitterionic monolayers in aqueous environments were quantified using atomic force microscope. Compared to cationic MTAC ([2-(methacryloyloxy)ethyl]trimethylammonium chloride), which exhibited an adhesion energy of ∼1.342 mJ/m2 with HA due to the synergistic effect of electrostatic attraction and possible cation-π interaction, anionic SPMA (3-sulfopropyl methacrylate) showed a weaker adhesion energy (∼0.258 mJ/m2) attributed to the electrostatic repulsion. Zwitterion-like MTAC/SPMA mixture, driven by electrostatic attraction between opposite charges, formed a hydration layer that prevented the interaction with HA, thereby considerably reducing adhesion energy to ∼0.123 mJ/m2. In contrast, zwitterionic MPC (2-methacryloyloxyethyl phosphorylcholine) and DMAPS ([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide) displayed ultralow adhesion energy (0.06–0.07 mJ/m2) with HA, arising from their strong dipole moments which could induce a tight hydration layer that effectively inhibited HA fouling. The pH-mediated electrostatic interaction resulted in the increased adhesion energy for MTAC but decreased adhesion energy for SPMA with elevated pH, while the adhesion energy for zwitterion-like and zwitterionic surfaces was independent of environmental pH. Density functional theory (DFT) simulation confirmed the strong binding capability of MPC and DMAPS with water molecules (∼–12 kcal mol−1). This work provides valuable insights into the molecular interaction mechanisms underlying humic-substance-fouling resistance of charged, zwitterion-like and zwitterionic materials at the nanoscale, shedding light on developing more effective strategy for HA antifouling in water treatment. [ABSTRACT FROM AUTHOR]

Cell mechanics are a biophysical indicator of cell state, such as cancer metastasis, leukocyte activation, and cell cycle progression. Atomic force microscopy (AFM) is a widely used technique to measure cell mechanics, where the Young modulus of a cell is usually derived from the Hertz contact model. However, the Hertz model assumes that the cell is an elastic, isotropic, and homogeneous material and that the indentation is small compared to the cell size. These assumptions neglect the effects of the cytoskeleton, cell size and shape, and cell environment on cell deformation. In this study, we investigated the influence of cell size on the estimated Young's modulus using liposomes as cell models. Liposomes were prepared with different sizes and filled with phosphate buffered saline (PBS) or hyaluronic acid (HA) to mimic the cytoplasm. AFM was used to obtain the force indentation curves and fit them to the Hertz model. We found that the larger the liposome, the lower the estimated Young's modulus for both PBS-filled and HA-filled liposomes. This suggests that the Young modulus obtained from the Hertz model is not only a property of the cell material but also depends on the cell dimensions. Therefore, when comparing or interpreting cell mechanics using the Hertz model, it is essential to account for cell size. [ABSTRACT FROM AUTHOR]

Atomic Force Microscopy (AFM) is crucial in mechanobiology for high-resolution imaging and nanomechanical measurements of biological samples, providing insights into their mechanical properties. However, AFM faces challenges such as tip damage and cantilever selection errors, impacting measurement accuracy. This study proposes a methodology using collagen-coated hydrogels with predefined stiffness for calibrating AFM measurements on soft biological materials. By facilitating appropriate cantilever selection, assessing systematic errors, and evaluating tip damage, this approach ensures reliable Young's modulus measurements. The proof of concept with human lung cells and tissue specimens demonstrates improved accuracy and reliability of AFM-based nanomechanical characterizations, essential for understanding cellular mechanics and disease progression. [ABSTRACT FROM AUTHOR]

Suggesting a curious comparison between the Victorian séance and the contemporary world of immersive virtual environments, Mike Phillips, Professor of Interdisciplinary Arts at the University of Plymouth, and Director of Research at i‐DAT.org, describes the new capabilities of the fulldome, which uses notions of the automatic movements of the planchette, the wooden token that traverses the alphanumeric surface of the notorious Ouija board, as a model for the development of a quasi‐participatory audience interface he dubs the 'phage'. Clusters of phage can be manipulated by the viewer‐occupiers of the dome to instigate all manner of formal, scalar and conceptual transpositionings. [ABSTRACT FROM AUTHOR]