Search Results (222)

To address prevalent industrial challenges, including the high cost of fabricating microstructures via photolithography and 3D printing, impurity residues easily generated by conventional physical/chemical pore-forming techniques, and the limited sensitivity of regular capacitive sensors, this paper innovatively proposes an integrated low-temperature in situ gas foaming strategy using ammonium bicarbonate for the fabrication of porous TPU-based ionic gels. Relying on the complete gaseous decomposition property of ammonium bicarbonate upon heating, a three-dimensionally interconnected continuous porous network is spontaneously constructed inside the polymer matrix. Thermoplastic polyurethane (TPU) is selected as the continuous polymer phase, and [EMIM][TFSI] imidazolium ionic liquid is blended as the ion source to synthesize composite ionic gel substrates. A PDMS composite slurry filled with graphene is employed to prepare flexible substrates, followed by low-temperature oxygen plasma surface modification to introduce polar functional groups such as hydroxyl and carboxyl onto electrode surfaces. A standard sandwich-structured ionic pressure sensor with the configuration of “top modified electrode—porous ionic gel dielectric layer—bottom modified electrode” is finally assembled. The porous framework and modified electrodes constitute a dual synergistic enhancement system: the porous structure markedly reduces the equivalent elastic modulus of the gel and improves its compressive deformation capacity; polar-modified electrodes optimize the interfacial compatibility between electrodes and gels, shorten ion migration paths and lower interfacial contact resistance. Systematic calibration of multiple batches of parallel samples reveals that the as-fabricated sensor achieves a high sensitivity of 25.3 kPa⁻¹ across the full measuring range from 0 to 1000 kPa with a linear fitting coefficient R² = 0.992. The loading response time and unloading recovery time of the device are 60 ms and 80 ms respectively, with a performance degradation of less than 3% after 1000 consecutive loading–unloading cycles, featuring low hysteresis error and excellent signal repeatability. Multi-scenario in vivo wearable tests on human subjects verify that the device can precisely capture subtle fluctuations of radial artery pulse and periodic laryngeal deformation during swallowing, distinguish characteristic waveform patterns of various English words according to differences in vocal cord vibration, and accurately detect bending motions when attached to finger joints. The entire fabrication process adopts common chemical raw materials and standard laboratory equipment without expensive micro-nano processing facilities, featuring convenient raw material procurement and high process fault tolerance, which enables large-area coating-based mass production. This work delivers a novel technical route for the low-cost large-scale production of high-performance ionic flexible sensors and bears significant industrialization reference value for applications in wearable medical monitoring, bionic robotic electronic skin, flexible human–machine interactive touch panels and other related fields. Full article

Calving in cattle is divided into two main stages: dilation and expulsion, during which timely assistance can reduce reproductive losses. This study presents a smart ear-mounted device as a proof-of-concept heart-rate monitoring platform for calving-stage assessment in dairy cows. The prototype preserves the form factor of a conventional ear tag and integrates a MAX30105 optical sensor, an Arduino Nano microcontroller, local micro-SD storage, and an autonomous power supply. Field tests were conducted in Holstein cows at Rancho El Pinar, Trancoso, Zacatecas, Mexico. Heart rate was recorded every 10 min and grouped according to physiological stages around calving. The results showed distinctive heart rate patterns, with higher values during dilation and lower values after delivery, supporting the use of ear-mounted heart rate monitoring as a non-invasive descriptive marker of stage-related physiological variation around labor. An average temperature profile from 70 h before to 50 h after calving was also incorporated as complementary descriptive evidence of peripartum physiological variation. Because heart rate is a non-specific physiological variable affected by stress, movement, ambient temperature, feeding, health status, and sensor contact, the present study does not propose HR as a stand-alone or definitive predictor of calving or dystocia. Instead, the device is presented as a proof-of-concept platform for future multi-indicator monitoring and validation studies. The proposed system is presented as a proof-of-concept invention that combines a practical wearable format with physiological monitoring and a conceptual decision-support logic that remains to be validated and integrated with additional indicators before any field implementation. Full article

Ultra-High Molecular Weight Polyethylene (UHMWPE), the standard base material in ski manufacturing, offers excellent gliding performance but exhibits limited mechanical and scratch resistance on hard and icy snow conditions. In this work, stainless steel is proposed as a mechanically robust alternative, and its inherently higher friction against snow is addressed through surface engineering. The snow friction behavior of 301H stainless steel surfaces decorated with fishbone-like microstructures combined with Laser-Induced Periodic Surface Structures (LIPSSs) was investigated using a custom-built snow tribometer. Several pattern designs, with different pitch distances and depths, were engraved using femtosecond laser pulse irradiation. We conducted morphological, physical, and chemical investigations through microscopy, static contact angle measurements, and X-ray Photoelectron Spectroscopy analyses. Results indicate that the gliding performance is not directly related to the modifications in surface chemistry and wetting behavior of the samples but is affected by the geometry and orientation with respect to the sliding direction of the specific micro- and nano-features. Overall, we achieved friction coefficient values comparable to those found in UHMWPE with a fast and economically sustainable single-step laser-texturing process. This approach allows the industrial up-scaling of the fishbone-texture design to real-size alpine ski prototypes. Full article

The growing request for more sustainable materials and environmentally friendly nanofabrication methods in the electronics field has recently driven the scientific community in the development of bio-derived materials as an alternative to conventional lithographic resists. In this work, we used chitosan, a biodegradable and biocompatible polysaccharide, as a green direct-write resist material for Atomic Force Microscopy-based nanolithography. Chitosan thin layers were obtained by spin coating and systematically characterized, in terms of thickness and surface roughness, demonstrating nanoscale smoothness and tunable film thickness. Three Pulse–Atomic Force Lithography (P-AFL) approaches, i.e., Constant Pulse, Gradient Pulse, and Raster Pulse AFL methods, were used to pattern nanostructures with constant-depth nanogrooves, variable-depth (2.5D) profile, and three-dimensional nanoholes on chitosan films. The results reveal high pattern fidelity, reproducibility, and tunability of feature dimensions as a function of applied force and scanning direction. Moreover, the RP-AFL technique enabled the fabrication of well-defined 3D nanostructures with depths matching the film thickness, which is a prerequisite for subsequent pattern transfer. This experimental work provided a first proof-of-concept to adopt chitosan as a more sustainable alternative with respect to conventional resists. Moreover, the results highlight P-AFL methods as a versatile and low-impact nanofabrication strategy, contributing to the development of greener micro- and nano-manufacturing technologies. Full article

Poly(3,4-ethylenedioxythiophene) (PEDOT)-based gels have emerged as a prominent class of functional conductive materials, owing to their unique electromechanical coupling characteristics that integrate electrical functionality and mechanical adaptability. This review systematically elucidates the electromechanical properties of PEDOT-derived gels—defined as the synergistic response of electrical behaviors (conductivity, carrier mobility, electrochemical stability) and mechanical performances (flexibility, stretchability, tensile strength, bending resistance)—under mechanical deformation, as well as their mutual regulatory mechanisms. Focusing on how preparation processes and structural regulation modulate these electromechanical properties, this work first introduces the development history, intrinsic conductive mechanisms, and inherent electromechanical characteristics of PEDOT. It then systematically summarizes mainstream synthesis methods, analyzing their effects on balancing mechanical flexibility and electrical conductivity. Addressing the brittleness and poor electromechanical stability of pure PEDOT, this review further explores composite synergistic mechanisms with conductive/non-conductive polymers, metallic materials, inorganic nanoparticles, and biomaterials, clarifying how interfacial interactions optimize mechanical deformability while preserving or enhancing electrical performance. Finally, it summarizes the applications of PEDOT-based composites in electromechanically compatible fields including flexible sensing, micro/nano patterning, implantable biomedicine, anti-corrosion protection, and energy storage. This review aims to clarify the connotation of PEDOT’s electromechanical properties, refine the focus of relevant research, and provide a theoretical basis for designing high-performance PEDOT-based gels with balanced electromechanical properties. Full article

Trends in Micro- and Nano-Lithography required for future development of large area applications ranging from high-packing-density electronics to solar cells are surveyed and outlined. Strategies to use direct laser writing to define etch masks over large areas by: (i) fixed beam moving stage and (ii) moving beam moving stage approaches are presented. The extension of planar 2D and stacked 2D (or 2.5D) fabrication methods into 3D micro- and nano-fabrication is discussed. One of the essential future characteristics of 3D nanolithography is real-time feedback capability. This can be realised via inherent 3D-capable holography, which bridges lithographic exposure control, wavefront sensing, and adaptive feedback, providing a pathway to stitch-free, large-area 3D patterning. The future of micro-fabrication is expected to evolve via highly specialised 3D architecture design and reduction in post-processing steps. Full article

Huanglongbing (HLB), primarily caused by ‘Candidatus Liberibacter asiaticus’ (CLas), threatens global citrus production. Deciphering the molecular interplay between citrus and CLas is crucial for successful control. This review synthesizes current understanding of the molecular mechanisms underlying citrus-CLas interactions, providing a comprehensive overview that spans immune signaling, hormonal and metabolic reprogramming, non-coding RNA-mediated regulation, pathogen effector biology, and emerging biotechnological interventions. We detail the hierarchical host response: initial immune recognition via pattern recognition receptors, triggering reactive oxygen species bursts and calcium signaling. Moreover, hormonal network reprogramming and their complex interplay in defense/susceptibility are examined. Transcriptomic studies have revealed key features of metabolic reprogramming, including suppression of photosynthesis and impairment of phloem function. Additionally, long-term strategies like cell wall reinforcement, accumulation of defensive compounds such as flavonoids and terpenoids, and roles of post-transcriptional regulation of microRNAs are discussed. Conversely, CLas counter-defense, notably effector-mediated immunity suppression and host metabolism manipulation, is also considered. Comparative transcriptomics between tolerant and susceptible varieties identifies tolerance or resistance genes/pathways for breeding and engineering. Despite this progress, critical knowledge gaps remain, particularly regarding the precise molecular mechanisms of CLas immune evasion and effector-mediated suppression, the genetic basis of natural tolerance, and the field-level efficacy of defense priming strategies. Future research directions should integrate single-cell omics, CRISPR/Cas9 editing, nano-enabled delivery, and microbiome engineering to bridge these gaps and accelerate HLB-tolerant/resistant citrus development. This review synthesizes how molecular profiling advances understanding of citrus defense mechanisms against HLB, and underscores the imperative for interdisciplinary research and global collaboration. Full article

Optical tweezers (OTs) serve as a core contactless manipulation tool at the micro- and nano-scale, with wide applications in physics, biology, colloid science and other fields. However, conventional single-beam gradient force OTs are limited by diffraction, optical damage, low throughput, and system complexity. To meet the demand for large-scale particle manipulation in complex environments, speckle optical tweezers (SOTs) based on random optical fields have emerged as a promising alternative to conventional OTs that transform random speckle patterns into a controllable manipulation resource. Since their formal establishment, SOTs have developed a solid theoretical foundation and diverse implementation platforms with key breakthroughs in micro- and nanoparticle manipulation. This paper systematically reviews the origin and development of SOTs, elaborates their core principles, summarizes the statistical properties of speckle fields, and introduces typical configurations based on random media, multimode fibers, and spatial light modulators. It also highlights the unique value of SOTs in micro- and nanoparticle manipulation, active particle dynamics, and cold atom physics, with advantages of high throughput, low cost, and environmental adaptability. Finally, future development trends are discussed, including intelligent regulation of optical fields, interdisciplinary applications, system miniaturization and multi-technology integration. This review provides a comprehensive reference for the theoretical development, system optimization, and practical application of SOTs in fields such as statistical physics, biomedicine, microfluidics, and quantum science. Full article

Background: Mild traumatic brain injury (mTBI) is frequently associated with persistent cognitive and psychosocial symptoms, yet biological correlates of recovery remain poorly understood, particularly among Asian and Pacific Islander (API) populations. Pre-injury psychosocial adversity may further shape post-injury recovery trajectories. This pilot study examined associations between participation in a 2-week, home-based, dual-task cognitive–walking intervention (Daily Brain Exercise; DBE) and changes in cognitive, psychological, and salivary microRNA (miRNAs) measures among APIs with and without a self-reported history of mTBI. Methods: API participants completed remote cognitive testing (CNS Vital Signs), psychosocial assessments (Neuro-QoL), and saliva collection before and after DBE participation. Salivary RNA was purified, and miRNA expression was profiled using nCounter^® Human v3 miRNA Expression Panels (NanoString). Differential expression analyses were conducted using ROSALIND^® platform (OnRamp Bioinformatics, San Diego, CA, USA), a cloud-based bioinformatics analysis system, to calculate fold changes and p-values. Pre-injury psychosocial adversity was assessed via the Trauma History Screen and examined descriptively as a contextual modifier of functional outcomes. Results: Twenty-one APIs (mean age 22.9 years; 76.7% female) were enrolled, including 14 individuals with a self-reported history of mTBI (mean 4.64 years post-injury; 50% with multiple injuries). Following DBE participation, increases in cognitive flexibility and executive function scores were observed in both mTBI and control groups. Additional increases in psychomotor speed, processing speed, sleep disturbance, and depressive symptoms were observed descriptively within the mTBI group. Subgroup analyses suggested variability in pre–post patterns across combinations of mTBI history and pre-injury psychosocial adversity. Exploratory miRNA analyses identified seven miRNAs that were differentially expressed in the mTBI group following DBE (unadjusted p < 0.005), including hsa-miR-7-5p, previously reported in association with neurodevelopmental and neurological pathways. Conclusions: In this pilot, feasibility-focused study, participation in a brief, home-based, dual-task intervention was associated with descriptive changes in selected cognitive and psychosocial measures among APIs, particularly those with a history of mTBI and pre-injury adversity. The observed subgroup patterns warrant confirmation in adequately powered, controlled studies. Exploratory changes in salivary miRNAs co-occurred with functional improvements, thus generating a hypothesis for a future investigation. Full article

Antireflection surfaces play an indispensable role in modern optics, with extensive applications covering optical windows and other precision optical components. The fabrication of anti-reflection surfaces frequently relies on micro/nano-structuring technologies. However, the fabricated micro/nanostructures typically experience performance degradation in transmission enhancement caused by abrasion during operation. To address this problem, we designed and fabricated a double-sided nanocone structure shielded by a protective armor layer. This armor layer efficiently prevents surface mechanical wear and preserves the nanocone structures, leading to almost constant transmittance of the anti-reflection surface even after abrasion. The anti-reflection surface was fabricated by first patterning a square grid armor on one side of fused silica via photolithography, followed by the preparation of an etching mask and nanocone structures using reactive ion etching (RIE). Nanocones were then fabricated on the opposite side of the substrate, finally forming the double-sided nanocone structure. The fabricated armor-protected double-sided nanocone structure exhibited an increase in the average transmittance from 93.43% to 98.31% within the wavelength range of 800–1200 nm. After abrasion testing under 10 MPa pressure, the nanocones under the protective armor showed almost no damage, and the average transmittance remained at approximately 97.85%, demonstrating the outstanding mechanical robustness of the proposed design. Full article

This paper evaluates the current maturity of automatic code-generation workflows for deploying modern CNN-based object detectors on embedded GPU platforms. We compare a native pipeline against a code generation pipeline through a Model-Based Engineering (MBE) approach, using YOLOv8/YOLOv9 inference on NVIDIA Jetson Orin Nano and Jetson AGX Orin as representative edge-GPU workloads. We report detection-quality metrics (mAP, PR curves) and system-level metrics (latency distribution and initialization overhead) under a controlled single-class scenario based on a CARLA-generated sequence with frame-level annotations. Absolute accuracy and latency values are scenario-dependent and may vary under different camera optics, illumination, motion blur, sensor noise, occlusion patterns, and multi-class scene. Results quantify the performance gap between code generation and native pipelines and show that, for the evaluated workloads, the automated pipeline remains less competitive in both latency and accuracy. We discuss the implications of this gap for deployment workflows in safety-oriented domains, and we outline bottlenecks that should be addressed. The study is intended as a controlled traffic-light detection micro-benchmark and does not aim to validate full ADAS perception stacks. Full article

Biomimetic anisotropy is defined as intentionally engineered, nature-inspired directional differences in structure, chemistry, roughness, stiffness, or pore architecture. These directional differences lower transport resistance in one direction relative to the opposite direction, which results in rectified transport. In this review, anisotropy design is synthesized across surfaces, porous materials, and soft systems, with transport considered for droplets, low-surface-tension liquids, particles, and soft objects. Biological inspirations are summarized first, and the design lessons that can be transferred to engineered platforms are then extracted. Key anisotropic architectures are classified next, including ratchets and sawtooth textures, bristle- or setae-like fibrillar arrays, grooves and wedges, asymmetric pores and membranes, chemically patterned surfaces, and hierarchical micro–nano combinations. Practical fabrication methods and material choices are reviewed thereafter, spanning micro- and nanofabrication, additive manufacturing, coatings and surface modification, and responsive soft matter. The field is then organized mechanistically around how anisotropy generates directionality through contact-line pinning asymmetry, curvature-driven capillary pressure bias, compliance and elastocapillary coupling, and active rectification under oscillatory forcing. Finally, these mechanisms are connected to application needs in pump-free microfluidics and sampling, long-distance open transport, environmental water management, and fouling-prone self-cleaning systems. Throughout the review, design-to-function links are emphasized, and open challenges are highlighted, including durability under real fluids and contaminants as well as scalable manufacturing and integration. Full article

Cleft palate only (CPO) is a multifactorial craniofacial malformation with significant genetic and epigenetic contributions. Among these, microRNAs (miRNAs) have emerged as key regulators of palate development, although their alterations in CPO remain incompletely characterized. In this study, we performed a comprehensive miRNA expression analysis on palatal tissues from an Italian cohort of non-syndromic CPO patients, compared with a human embryonic palatal mesenchymal (HEPM) cell line. Using the NanoString^® nCounter^® platform for miRNA profiling, we identified significant deregulation of several miRNAs, notably the upregulation of miR-205-5p and miR-200c-3p and the downregulation of miR-125a-5p in CPO tissues. Based on these expression changes, a functional analysis was carried out to identify potential target genes. Validation in primary cell cultures derived from patient tissues confirmed these expression patterns. Functional analyses and target predictions implicated PAX9, a key transcription factor essential for palatogenesis, as a probable target of miR-205-5p, while miR-125a-5p was associated with the regulation of PRTG and PRSS35—genes involved in neural crest cell biology and extracellular matrix remodeling, respectively. Although modulation of certain predicted targets of miR-200c-3p was observed, in vitro inhibition experiments did not show significant changes in gene expression, highlighting the complexity of miRNA regulatory networks and the need for further studies to unravel these interactions. These findings identify miRNA alterations associated with CPO tissue and fibroblasts, highlighting novel candidate pathways for further mechanistic and therapeutic investigation. Full article

In this research, an innovative scheme to generate heterogeneous acoustofluidic distributions in various pseudo-Sierpiński-carpet-shaped chambers with different filling fractions and cross-sectional configurations has been proposed and calculated for topographical manipulation of large-scale micro-particles. All of the structural components positioned in the pseudo-fractal chambers are symmetrically distributed in space, and all ultrasonic radiation surfaces hold the unified settings of input frequency point, oscillation amplitude, and initial phase distribution along their respective normal directions. A large number of fascinating acoustofluidic patterns can be generated in the originally-static pseudo-Sierpiński-carpet-shaped chambers at different recursion levels without complicated vibration parameter modulation. The simulation results of acoustofluidic distributions and particle motion trajectories under different radiation surface arrangements further demonstrate the manipulation performance of these specially designed devices, and indicate that controllable spatial partitioning and intensity modulation of the acoustofluidic field can be achieved by adjusting the hierarchical order, cross-sectional configuration and combination mode of the radiation surfaces. Unlike the existing device construction method of miniaturized microfluidic systems, the artificial introduction of fractal elements like Sierpiński carpet/triangle, Koch snowflake, Mandelbrot set, Pythagoras tree, etc., can provide extraordinary perspectives and expand the application range of the acoustofluidic effect, which also makes ultrasonic micro/nano-scale manipulation technology more abundant and diversified. This exploratory research indicates the potential possibility of applying fractal structures as alternative component parts to purposefully customize acoustofluidic distributions for the further research of patterned manipulation of bio-organisms and navigation of micro-robot swarms in brand new ways that cannot be achieved through traditional methods. Full article

In mechanical engineering, interest in reliable and practicable technologies for nano- and microstructuring of tool surfaces is increasing. Femtosecond laser structuring offers a promising approach that combines high processing speeds with high precision. However, a knowledge gap remains regarding the optimal process parameters for achieving specific surface patterns on hot-work tool steel substrates. The current study aims to investigate the effects of laser scanning parameters on the formation of self-organized surface structures and the resulting topography and morphology. Therefore, samples were irradiated using a 300 fs laser with linearly polarized light (λ = 1030 nm). Scanning electron microscopy revealed four structure types: laser-induced periodic surface structures (LIPSSs), micrometric ripples, micro-crater structures, and pillared microstructures. The results for surface area and line roughness indicate that high laser pulse overlaps lower the strong ablation threshold more effectively than high scanning line overlaps, promoting the formation of pillared microstructures. For efficient ablation and increased surface roughness, higher pulse overlaps are therefore advantageous. In contrast, at low fluences, higher scanning line overlaps support a more homogeneous formation of nanostructures and reduce waviness. Full article