Search Results (218)

Emerging research indicates that neuronal activity is maintained by an architectural system of protons in a multi-scale fashion. Proton architecture is formed when organelles (such as mitochondria, endoplasmic reticulum, lysosomes, synaptic vesicles, etc.) are coupled together to produce dynamic energy domains. Techniques have been developed to visualize protons in neurons; recent advances include near-atomic structural imaging of organelle interfaces using cryo-tomography and nanoscale resolution imaging of organelle interfaces and proton tracking using ultra-fast spectroscopy. Results of these studies indicate that protons in neurons do not diffuse randomly throughout the neuron but instead exist in organized geometric configurations. The cristae of mitochondrial cells create oscillating proton micro-domains that are influenced by the curvature of the cristae, hydrogen bonding between molecules, and localized changes in dielectric properties that result in time-patterned proton signals that can be used to determine the metabolic load of the cell and the redox state of its mitochondria. These proton patterns also communicate to the rest of the cell via hydrated aligned proton-conductive pathways at the mitochon-dria-endoplasmic reticulum junctions, through acidic lipid regions, and through nano-tethered contact sites between mitochondria and other organelles, which are typically spaced approximately 10–25 nm apart. Other proton architectures exist in lysosomes, endosomes, and synaptic vesicles. In each of these organelles, the V-ATPase generates steep concentration gradients across their membranes, controlling the rate of cargo removal from the lumen of the organelle, recycling receptors from the surface of the membrane, and loading neurotransmitters into the vesicles. Recent super-resolution pH mapping has indicated that populations of synaptic vesicles contain significant heterogeneity in the amount of protons they contain, thereby influencing the amount of neurotransmitter released per vesicle, the probability of vesicle release, and the degree of post-synaptic receptor protonation. Additionally, proton gradients in each organelle interact with the cytoskeleton: the protonation status of actin and microtubules influences filament stiffness, protein–protein interactions, and organelle movement, resulting in the formation of localized spatial structures that may possess some type of computational significance. At multiple scales, it appears that neurons integrate the proton micro-domains with mechanical tension fields, dielectric nanodomains, and phase-state transitions to form distributed computing elements whose behavior is determined by the integration of energy flow, organelle geometry, and the organization of soft materials. Alterations to the proton landscape in neurons (e.g., due to alterations in cristae structure, drift in luminal pH, disruption in the hydration-structure of the cell, or imbalance in the protonation of cytoskeletal components) could disrupt the intracellular signaling network well before the onset of measurable electrical or biochemical pathologies. This article will summarize evidence indicating that proton–organelle interaction provides a previously unknown source of energetic substrate for neural computation. Using an integrated approach combining nanoscale proton energy, organelle interface geometry, cytoskeletal mechanics, and AI-based multiscale models, this article outlines current principles and unresolved questions related to the subject area as well as possible new approaches to early detection and precise intervention of pathological conditions related to altered intracellular energy flow. Full article

This study investigates the Serial Discontinuity Concept (SDC) by analyzing the size of phytoplankton structures across 13 cascade dams in the fragmented East River, China. The results showed that dam flow-regulation minimized seasonal differences in total chlorophyll-a (Chl-a). Spatially, midstream Chl-a was higher during the dry period, whereas increased wet periods were linked to reservoir effects and nutrient conditions. Nano-phytoplankton dominated during both periods, while micro-phytoplankton declined during wet periods due to higher pH and transparency. Micro-Chl-a increased downstream in dry periods as a result of dissolved oxygen levels and silicate. Self-organizing maps revealed greater size–class variability during dry periods, with pH and conductivity identified as key regulators. Aulacoseira granulata (micro-phytoplankton) and Anabaena oscillarioides (also micro-phytoplankton) were co-dominant. This pattern suggests that the flow regulation and water impoundment by cascade dams during the wet period created localized lentic conditions with enhanced water stability, which favored the proliferation of these species, despite the increased seasonal discharge at the basin scale. These findings support the SDC in that (1) longitudinal Chl-a variations empirically validated SDC, especially during dry periods, and (2) a spatially periodic Chl-a pattern was identified, termed the Cascade Cycle of SDC (CC-SDC). Full article

Nanomaterials are usually associated with modern technologies and advanced processing methods. Three silver Dacian bracelets within Cehei hoard (Salaj County, Romania) are tougher than they should be according to the apparently higher silver content. The microstructural investigation reveals that all three bracelets have silver content of about 90 wt.%. The metallographic inspection of a bracelet sample reveals a very refined microstructure of α grain while fewer eutectic grains are almost undetectable, indicating intensive plastic deformation. XRD patterns of the bracelets reveal relevant peaks for silver (without copper) having a much-broadened aspect indicating nanostructural level. The nano-grains were evidenced at high magnification of SEM imaging: 55 nm for bracelet 1, 95 nm for bracelet 2 and 75 nm for bracelet 3. Elemental maps reveal that the nanograins are basically formed by α phase; the finest eutectic traces are situated and uniformly dispersed within α phase, appearing as small red spots. Vickers µHV10 micro indentation was calibrated on a pure silver 999.9 ‰ in annealed state, resulting in 37 HV10. The nanostructured bracelets have about 56 µHV10 for bracelet 1; 50 µHV10 for bracelet 2 and 52 µHV10 for bracelet 3. Dyrrachium drachmas have Vickers microhardness of about 37 µHV10. The obtained results confirm the historian’s supposition that Dyrrachium drachmas could be the source for silver but also clearly indicate that the final steps of bracelets manufacturing were effectuated by cold deformation with intensive cold hardening. It results that cold deformation of the bracelets rods induces a nanostructural state that significantly increases their microhardness instead of their higher silver title. Full article

The treatment of olive mill wastewater (OMW) remains a major environmental challenge due to its high organic load and phenolic content. This study investigates a combined approach using lime pretreatment and limestone (LS)-based adsorption for cost-effective and sustainable OMW remediation. Locally sourced limestone was used in both micro- and nanoscale forms, while lime (CaO) was produced by calcination. The materials were characterized using X-ray Diffraction pattern (XRD), Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET), and Point of Zero Charge (pH_PZC) analyses to evaluate surface properties relevant to adsorption. Lime pretreatment achieved notable reductions in total suspended solids (TSS, 99%), chemical oxygen demand (COD, 43%), and total phenolic content (TPC, 48%). Subsequent adsorption with nano-limestone (particles obtained through high-energy ball milling, followed by sieving, with a size distribution 400–500 nm) further enhanced pollutant removal, achieving up to 72% COD and 89% TPC reduction in batch experiments. Column studies confirmed the synergistic effect of mixed particle sizes, yielding 65% COD and 76% TPC removal. The combined process demonstrates the potential of lime–limestone composites as locally available and eco-friendly materials for OMW treatment. While promising, the results represent laboratory-scale findings; further optimization and long-term assessments are recommended for field applications. Full article

This paper investigates the laws governing the evolution of nanostructures on pre-patterned fused silica surfaces by energetic ion erosion. First, regular nanostructures are fabricated with the Focused Ion Beam (FIB) operating at optimized processing parameters. Then, as a function of the different ion fluences, the surface morphology evolution is studied on a surface with newly formed nanostructures. An experimental phenomenon of inter-transformation between nano-ripples and random dot-like structures is observed. In addition, the principles of the development of the nanostructures are analyzed theoretically. The simulation results fit well with the experiments. This work deeply studies the influence of the initial surface micro-morphology on the evolution of nanostructures, and is of great significance for the control of surface nanostructures generated by energetic ion sputtering. Full article

Microfluidic chips made of polydimethylsiloxane (PDMS) have shown significant application potential in aquatic environments with high microbial density, such as “marine ranches”, due to their high-throughput, high-efficiency and high-precision detection capabilities. This technology can rapidly identify pathogenic microorganisms or harmful particles in aquaculture systems, thereby providing urgently needed innovative methods for implementing preventive measures and enhancing aquaculture productivity. By regulating the micro-nano scale channel structure, microfluidic technology can precisely control fluid flow patterns, offering new insights and effective solutions for microbiological research and the separation and analysis of particulate matter. This paper first provides a concise overview of the application of microfluidic chip technology in the analysis of marine microorganisms. Subsequently, it focuses on the “compliance” phenomenon in PDMS-based microfluidic systems, systematically reviewing the potential mechanisms, latest progress and impacts of compliance behavior in mechanically elastic materials such as PDMS. Additionally, this article also investigates the role of “compliance” in key processes of microfluidic technology application, including the capture, separation, enrichment and detection of microorganisms and particles. Moreover, the relationship between surface wettability engineering and compliance phenomena is also explored. We believe that this review will contribute to enhancing the understanding and control of the mechanical behavior of microfluids and the particles they carry within microfluidic systems, providing valuable theoretical insights and practical guidance for researchers in this field. Full article

To investigate the influence patterns and underlying mechanisms of solid waste-derived Nano-Micro-Powder (NMP) materials on asphalt performance, this study selected nano-sized silica fume (a typical industrial solid waste) along with conventionally used hydrated lime and cement powders as representative modifiers. Based on material type, dosage, and particle size, the high-temperature rheological properties, low-temperature rheological behavior, and nano-scale mechanical characteristics of NMP-modified asphalt were systematically evaluated through dynamic shear frequency tests, Multiple Stress Creep Recovery (MSCR) tests, Bending Beam Rheometer (BBR) tests, and Atomic Force Microscopy (AFM) measurements. Additionally, the grey relational analysis method was employed to quantify the impact of key nanoparticle characteristics on modified asphalt performance. The results demonstrate the following: (1) With increasing NMP dosage and decreasing particle size, the complex modulus (G*) of modified asphalt increases significantly, while the creep recovery rate (R) rises and non-recoverable creep compliance (J_nr) decreases. The creep stiffness slope (m-value) diminishes under low-temperature conditions. (2) Among different NMP types, silica fume-modified asphalt exhibits the highest G*, R, and m-value parameters. (3) At the nanoscale, adhesion force, modulus, and surface roughness all increase with higher NMP dosage and smaller particle size. Silica fume demonstrates superior performance in these nano-mechanical properties compared to hydrated lime and cement powders. (4) Grey relational analysis reveals that specific surface area shows the strongest correlation with the overall performance of NMP-modified asphalt. Full article

Polymer gel-based triboelectric nanogenerators (TENGs) have emerged as versatile platforms for self-powered sensing due to their inherent softness, stretchability, and tunable conductivity. This review comprehensively explores the roles of polymer gels in TENG architecture, including their function as triboelectric layers, electrodes, and conductive matrices. We analyze four operational modes—vertical contact-separation, lateral-sliding, single-electrode, and freestanding configurations—alongside key performance metrics. Recent studies have reported output voltages of up to 545 V, short-circuit currents of 48.7 μA, and power densities exceeding 120 mW/m², demonstrating the high efficiency of gel-based TENGs. Gel materials are classified by network structure (single-, double-, and multi-network), matrix composition (hydrogels, aerogels, and ionic gels), and dielectric medium. Strategies to enhance conductivity using ionic salts, conductive polymers, and nanomaterials are discussed in relation to triboelectric output and sensing sensitivity. Morphological features such as surface roughness, porosity, and micro/nano-patterning are examined for their impact on charge generation. Application-focused sections detail the integration of gel-based TENGs in health monitoring (e.g., sweat, glucose, respiratory, and tremor sensing), environmental sensing (e.g., humidity, fire, marine, and gas detection), and tactile interfaces (e.g., e-skin and wearable electronics). Finally, we address current challenges, including mechanical durability, dehydration, and system integration, and outline future directions involving self-healing gels, hybrid architectures, and AI-assisted sensing. This review expands the subject area by synthesizing recent advances and offering a strategic roadmap for developing intelligent, sustainable, and multifunctional TENG-based sensing technologies. Full article

Tight sandstone gas is currently one of the largest unconventional oil and gas resources being developed. In actual reservoir development, the complex pore structure affects the distribution of residual gas and water during the displacement process. However, there is still a lack of experimental research on the multi-scale visualization of pore structures in high-water-content tight gas reservoirs. Therefore, based on the porosity and permeability properties of reservoir cores and the micropore throat structural characteristics, this study designs and prepares three micro-physical models with different permeability ranges. Through micro-experiments and visualization techniques, the microscopic flow phenomena and gas–water distribution in the pore medium are observed. When the water–gas ratio exceeds 5, the produced water type is free water; when the water–gas ratio is between 2 and 5, the produced water type is weak capillary water; and when the water–gas ratio is less than 2, the produced water type is strong capillary water. The latter two types are collectively referred to as capillary water. In the Jin 30 well area, the main types of produced water are first free water, followed by capillary water, accounting for 58.5%. The experimental results of the micro-physical models with different permeability levels show that the production pattern of formation water varies due to differences in pore connectivity. In the low-permeability model, the high proportion of nano-pores and small pore throats requires a large pressure difference to mobilize capillary water, resulting in a higher proportion of residual water. Although the pores in the medium-permeability model are larger, the poor connectivity of nano-pores leads to local water phase retention. In the high-permeability model, micro-fractures and micropores are highly developed with good connectivity, allowing for rapid mobilization of multi-scale water phases under low pressure. The connectivity of nano-pores directly impacts the mobilization of formation water in micron-scale fractures, and poor pore connectivity significantly increases the difficulty of capillary water mobilization, thus changing the production mechanism of formation water at different scales. Full article

Continuous monitoring of environmental and physiological parameters is essential for early diagnostics, real-time decision making, and intelligent system adaptation. Recent advancements in bio-microelectromechanical systems (BioMEMS) sensors have significantly enhanced our ability to track key metrics in real time. However, continuous monitoring demands sustainable energy supply solutions, especially for on-site energy replenishment in areas with limited resources. Artificial intelligence (AI), particularly large language models, offers new avenues for interpreting the vast amounts of data generated by these sensors. Despite this potential, fully integrated systems that combine self-powered BioMEMS sensing with AI-based analytics remain in the early stages of development. This review first examines the evolution of BioMEMS sensors, focusing on advances in sensing materials, micro/nano-scale architectures, and fabrication techniques that enable high sensitivity, flexibility, and biocompatibility for continuous monitoring applications. We then examine recent advances in energy harvesting technologies, such as piezoelectric nanogenerators, triboelectric nanogenerators and moisture electricity generators, which enable self-powered BioMEMS sensors to operate continuously and reducereliance on traditional batteries. Finally, we discuss the role of AI in BioMEMS sensing, particularly in predictive analytics, to analyze continuous monitoring data, identify patterns, trends, and anomalies, and transform this data into actionable insights. This comprehensive analysis aims to provide a roadmap for future continuous BioMEMS sensing, revealing the potential unlocked by combining materials science, energy harvesting, and artificial intelligence. Full article

In the context of critical challenges in curcumin-modified polyurethane synthesis—including limited curcumin bioavailability and suboptimal biodegradability/biocompatibility—a novel polyurethane material (Cur-PU) with good mechanical, shape memory, pH-responsive, and biocompatibility was synthesized via a one-pot, two-step synthetic protocol in which HO-PCL-OH served as the soft segment and curcumin was employed as the chain extender. The experimental results demonstrate that with the increase in Cur units, the crystallinity of the Cur-PU material decreases from 32.6% to 5.3% and that the intensities of the diffraction peaks at 2θ = 21.36°, 21.97°, and 23.72° in the XRD pattern gradually diminish. Concomitantly, tensile strength decreased from 35.5 MPa to 19.3 MPa, and Shore A hardness declined from 88 HA to 65 HA. These observations indicate that the sterically hindered benzene ring structure of Cur imposes restrictions on HO-PCL-OH crystallization, leading to lower crystallinity and retarded crystallization kinetics in Cur-PU. As a consequence, the material’s tensile strength and hardness are diminished. Except for the Cur-PU-3 sample, all other variants exhibited exceptional shape-memory functionality, with R_f and R_r exceeding 95%, as determined by three-point bending method. Analogous to pure curcumin solutions, Cur-PU solutions demonstrated pH-responsive chromatic transitions: upon addition of hydroxide ion (OH⁻) solutions at increasing concentrations, the solutions shifted from yellow-green to dark green and finally to orange-yellow, enabling sensitive pH detection across alkaline gradients. Hydrolytic degradation studies conducted over 15 weeks in air, UPW, and pH 6.0/8.0 phosphate buffer solutions revealed mass loss <2% for Cur-PU films. Surface morphological analysis showed progressive etching with the formation of micro-to-nano-scale pores, indicative of a surface-erosion degradation mechanism consistent with pure PCL. Biocompatibility assessments via L929 mouse fibroblast co-culture experiments demonstrated ≥90% cell viability after 72 h, while relative red blood cell hemolysis rates remained below 5%. Collectively, these findings establish Cur-PU as a biocompatible material with tunable mechanical properties, and pH responsiveness, underscoring its translational potential for biomedical applications such as drug delivery systems and tissue engineering scaffolds. Full article

Mesenchymal stromal cells (MSCs) have demonstrated therapeutic efficacy across numerous clinical applications, with evidence suggesting their paracrine effects, particularly through extracellular vesicles (EVs), possibly driving functional outcomes. In this study we perform the comprehensive characterization of microRNA expression profiles in human MSC-derived EVs (MSC-EV) compared to their parental cells, cultured under clinically relevant xeno-free conditions. MSCs were isolated from the bone marrows of healthy donors and characterised according to the International Society for Cellular Therapy criteria, while MSC-EVs were isolated using differential ultracentrifugation and validated according to the International Society for Extracellular Vesicle guidelines. NanoString profiling identified 590 mature microRNAs expressed across both populations, with 42 being significantly differentially expressed between MSC-EVs and parental MSCs. Five microRNAs were distinctly highly expressed in MSCs and five in MSC-EVs, while fifteen of the top twenty most abundant microRNAs showed high expression in both populations. MicroRNA expression patterns were validated in an independent cohort. Functional pathway analysis of differentially expressed microRNAs showed enrichment of key biological processes including cell proliferation, differentiation, and immune regulation. This standardised profiling approach develops our understanding of MSC/MSC-EV microRNA cargo, using a transparent methodological approach that allows for the improved comparability of datasets for the development and advancement of MSC-EV therapeutics. Full article

Bone is a preferred site for disseminated tumor cells, yet the molecular mechanisms that prepare the skeletal microenvironment for metastatic colonization are only beginning to be understood. At the heart of this process are extracellular vesicles (EVs), nano-sized, lipid-encapsulated particles secreted by cancer cells and stromal components. This review consolidates current findings that position EVs as key architects of the bone-metastatic niche. We detail the biogenesis of EVs and their organotropic distribution, focusing on how integrin patterns and bone-specific ligands guide vesicle homing to mineralized tissues. We then outline the sequential establishment of the pre-metastatic niche, driven by EV-mediated processes including fibronectin deposition, stromal cell reprogramming, angiogenesis, neurogenesis, metabolic reconfiguration, and immune modulation, specifically, the expansion of myeloid-derived suppressor cells and impaired lymphocyte function. Within the bone microenvironment, tumor-derived EVs carrying microRNAs and proteins shift the balance toward osteoclastogenesis, inhibit osteoblast differentiation, and disrupt osteocyte signaling. These alterations promote osteolytic destruction or aberrant bone formation depending on tumor type. We also highlight cutting-edge imaging modalities and single-EV omics technologies that resolve EV heterogeneity and identify potential biomarkers detectable in plasma and urine. Finally, we explore therapeutic approaches targeting EVs, such as inhibition of nSMase2 or Rab27A, extracorporeal EV clearance, and delivery of engineered, bone-targeted vesicles, while addressing translational challenges and regulatory considerations. This review offers a roadmap for leveraging EV biology in predicting, preventing, and treating skeletal metastases by integrating advances across basic biology, bioengineering, and translational science. Full article

Engineered nano- and microparticles are considered as promising tools in biomedical applications, such as imaging, sensing, and drug delivery. Protein adsorption on these particles in biological media is an important factor affecting their properties, cellular interactions, and biological fate. Understanding the parameters determining the efficiency and pattern of protein adsorption is crucial for the development of effective biocompatible particle-based applications. This review focuses on the influence of the morphological and physicochemical properties of particles on protein adsorption, including the pattern and amount of the adsorbed protein species, as well as the relative abundance of proteins with specific functions or physicochemical parameters. The effects of functionalization of the particle surface with polyethylene glycol, zwitterions, zwitterionic polymers, or proteins on the subsequent protein adsorption are analyzed. In addition, the dependences of protein adsorption on the protein species, biological buffers, fluids, tissues, and other experimental conditions are looked into. The influence of protein adsorption on the targeting efficiency of particle-based delivery systems is also discussed. Finally, the effect of the adsorbed protein corona on the interaction of the engineered micro- and nanoparticles with cells and the roles of specific proteins adsorbed on the particle surface in the recognition of the particles by the immune system are considered. Full article

Three-dimensional (3D) photolithography has found wide applications in microelectronics, optoelectronics, biomedicine, etc. Traditionally, it requires repetitive exposure and developing cycles. Meanwhile, a laser direct writing (LDW) system with a digital micromirror device (DMD) enables high-speed maskless lithography with programmable doses. In this paper, we propose a quasi-3D digitized photolithography via LDW with a DMD to remove multiple developing cycles from the process. This approach quantizes the dose of the 3D geometry and stores it in a grayscale image. And the entire dose distribution can be formed by overlapping the exposures with sliced binary dose maps from the above grayscale dose map. In the image slicing algorithm, a modified Golomb coding is introduced to make full use of the highest available exposure intensity. Both 1D multi-step patterns and diffractive optical devices (DOEs) have been fabricated to verify its feasibility. This type of digitized quasi-3D photolithography can be applied to fabricating DOEs, microlens arrays (MLAs), micro-refractive optical elements (μROEs), etc., and 3D molds for micro-embossing/nano-imprinting. Full article