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This study delves into the development of a novel 10 by 10 sensor array featuring 100 pressure sensor pixels, achieving remarkable sensitivity up to 888.79 kPa-1, through the innovative design of sensor structure. The critical challenge of strain sensitivity inherent is addressed in stretchable piezoresistive pressure sensors, a domain that has seen significant interest due to their potential for practical applications. This approach involves synthesizing and electrospinning polybutadiene-urethane (PBU), a reversible cross-linking polymer, subsequently coated with MXene nanosheets to create a conductive fabric. This fabrication technique strategically enhances sensor sensitivity by minimizing initial current values and incorporating semi-cylindrical electrodes with Ag nanowires (AgNWs) selectively coated for optimal conductivity. The application of a pre-strain method to electrode construction ensures strain immunity, preserving the sensor's electrical properties under expansion. The sensor array demonstrated remarkable sensitivity by consistently detecting even subtle airflow from an air gun in a wind sensing test, while a novel deep learning methodology significantly enhanced the long-term sensing accuracy of polymer-based stretchable mechanical sensors, marking a major advancement in sensor technology. This research presents a significant step forward in enhancing the reliability and performance of stretchable piezoresistive pressure sensors, offering a comprehensive solution to their current limitations.
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The emergence of high-form-factor electronics has led to a demand for high-density integration of inorganic thin-film devices and circuits with full stretchability. However, the intrinsic stiffness and brittleness of inorganic materials have impeded their utilization in free-form electronics. Here, we demonstrate highly integrated strain-insensitive stretchable metal-oxide transistors and circuitry (442 transistors/cm2) via a photolithography-based bottom-up approach, where transistors with fluidic liquid metal interconnection are embedded in large-area molecular-tailored heterogeneous elastic substrates (5 × 5 cm2). Amorphous indium-gallium-zinc-oxide transistor arrays (7 × 7), various logic gates, and ring-oscillator circuits exhibited strain-resilient properties with performance variation less than 20% when stretched up to 50% and 30% strain (10,000 cycles) for unit transistor and circuits, respectively. The transistors operate with an average mobility of 12.7 ( ± 1.7) cm2 V-1s-1, on/off current ratio of > 107, and the inverter, NAND, NOR circuits operate quite logically. Moreover, a ring oscillator comprising 14 cross-wired transistors validated the cascading of the multiple stages and device uniformity, indicating an oscillation frequency of ~70 kHz.
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MXenes, with their remarkable attributes, stand at the forefront of diverse applications. However, the challenge remains in sustaining their performance, especially concerning Ti3C2Tx MXene electrodes. Current self-healing techniques, although promising, often rely heavily on adjacent organic materials. This study illuminates a pioneering water-initiated self-healing mechanism tailored specifically for standalone MXene electrodes. Here, both water and select organic solvents seamlessly mend impaired regions. Comprehensive evaluations around solvent types, thermal conditions, and substrate nuances underline water's unmatched healing efficacy, attributed to its innate ability to forge enduring hydrogen bonds with MXenes. Optimal healing environments range from ambient conditions to a modest 50 °C. Notably, on substrates rich in hydroxyl groups, the healing efficiency remains consistently high. The proposed healing mechanism encompasses hydrogen bonding formation, capillary action-induced expansion of interlayer spacing, solvent lubrication, Gibbs free energy minimizing MXene nanosheet rearrangement, and solvent evaporation-triggered MXene layer recombination. MXenes' resilience is further showcased by their electrical revival from profound damages, culminating in the crafting of Joule-heated circuits and heaters.
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This paper presents the design, fabrication, and implementation of a novel composite film, a polybutadiene-based urethane (PBU)/AgNW/PBU sensor (PAPS), demonstrating remarkable mechanical stability and precision in motion detection. The sensor capitalizes on the integration of Ag nanowire (AgNW) electrodes into a neutral plane, embedded within a reversibly cross-linkable PBU polymer. The meticulous arrangement confers pore-free and interfaceless sensor formation, resulting in an enhanced mechanical robustness, reproducibility, and long-term reliability. The PBU polymer is subjected to an electrospinning process, followed by sequential Diels-Alder (DA) and retro-DA reactions to produce a planarized encapsulation layer. This pioneering technology, based on electrospinning, allows for more flawless engineering of the neutral plane as compared to conventional film lamination or layer-by-layer spin-coating processes. This encapsulation, matching the thickness of the preformed PBU film, effectively houses the AgNW electrodes. The PAPS outperforms conventional AgNW/PBU sensors (APS) in terms of mechanical stability and bending insensitivity. When affixed to various body parts, the PAPS generates distinctive signal curves, reflecting the specific body part and degree of motion involved. The PAPS sensor's utility is further magnified by the application of machine learning and deep learning algorithms for signal interpretation. K-means clustering algorithm authenticated the superior reproducibility and consistency of the signals derived from the PAPS over the APS. Deep learning algorithms, including a singular 1D convolutional neural network (1D CNN), long short-term memory (LSTM) network, and dual-layered combinations of 1D CNN + LSTM and LSTM + 1D CNN, were deployed for signal classification. The singular 1D CNN model displayed a classification accuracy exceeding 98%. The PAPS sensor signifies a pivotal development in the field of intelligent motion sensors.
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With wearable devices featuring electrocardiogram (ECG) capabilities increasingly common, demand for accurate, simple ECG measurements has escalated. Although single-lead ECGs, which capture real-time heart rate and rhythm, are typically used in such devices, they encounter challenges related to the device-skin contact state, complicating serious heart disease prediction. While 12-lead ECGs provide superior measurements, they require wet electrodes, which are unsuitable for long-term use due to skin irritation and signal degradation over time. Dry electrodes have been explored as a potential resolution to this issue, yet they necessitate a substantial conductive surface area coupled with a stable contact to achieve low contact impedance with the skin. For the first time, we hereby propose a novel approach that simultaneously addresses the exigencies for substantial conductive surface coverage and remarkable contact stability, facilitating an ECG free from motion artifacts. The electrodes we propose are constituted by silver nanowires (AgNWs) entrenched beneath the surface of a polymer film, thereby displaying superior mechanical flexibility and lateral electrical conductivity. To counterbalance the restricted surface coverage of the embedded AgNW electrode, we integrated Ti3C2-based MXene nanosheets on the surface, thereby significantly enhancing the conductive coverage of the electrode surface. The electrostatic interaction between the functional groups on the MXene nanosheets' surface and the positively charged human skin facilitates spontaneous contact, yielding stable contact and diminished vulnerability to motion artifacts. This novel electrode design holds considerable potential for the long-term monitoring of cardiac health, offering signal quality superior to that of existing wet and dry electrodes.
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Nanofios , Humanos , Eletricidade Estática , Prata , Titânio , Eletrocardiografia , Eletrodos , PolímerosRESUMO
BACKGROUND: Pro-inflammatory cytokines secreted from activated macrophages and astrocytes are crucial mediators of inflammation for host defense. Among them, the secretion of IL-1ß, a major pro-inflammatory cytokine, is especially mediated by the activation of NLRP3 inflammasome. Pro-IL-1ß, which is produced in response to the invaded pathogens, such as LPS, is cleaved and matured in the NLRP3 inflammasome by the recognition of ATP. Excessively activated IL-1ß induces other immune cells, resulting in the up-regulation of inflammation. Therefore, regulation of NLRP3 inflammasome can be a good strategy for alleviating inflammation. OBJECTIVE: Our study aimed to examine whether 5-methylthiopentyl isothiocyanate, a sulforaphane analogue (berteroin), has an anti-inflammatory effect on the NLRP3 inflammasome activation induced by LPS and ATP. METHODS: Primary bone marrow-derived macrophages (BMDMs) and astrocytes were stimulated by LPS and ATP with the treatment of 5-methylthiopentyl isothiocyanate, a sulforaphane analogue. The secretion of pro-inflammatory cytokines was measured by ELISA, and the expression level of NLRP3 inflammasome-associated proteins was detected by western blot. The association of NLRP3 inflammasome was assessed by co-immunoprecipitation, and the formation of ASC specks was evaluated by fluorescent microscope. RESULTS: 5-Methylthiopentyl isothiocyanate, a sulforaphane analogue (berteroin), decreased the release of pro-inflammatory cytokines, IL-1ß, and IL-6 in the BMDMs. Berteroin notably prevented the formation of both NLRP3 inflammasome and ASC specks, which reduced the secretion of IL-1ß. Additionally, berteroin reduced the IL-1ß secretion and cleaved IL-1ß expression in the primary astrocytes. DISCUSSION AND CONCLUSION: These results indicated the anti-inflammatory effects of 5-methylthiopentyl isothiocyanate (berteroin) by regulating NLRP3 inflammasome activation, suggesting that berteroin could be the potential natural drug candidate for the regulation of inflammation.
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Alzheimer's disease (AD) is accompanied by neural cell loss and memory deficit. Neural cell death, occurring via apoptosis and autophagy, is widely observed in the AD brain in addition to neuroinflammation mediated by necroptosis and the NLRP3 inflammasome. Neurotoxicity induced by amyloid-beta (Aß) and tau aggregates leads to excessive neural cell death and neuroinflammation in the AD brain. During AD progression, uncontrolled neural cell death results in the dysregulation of cellular activity and synaptic function. Apoptosis mediated by pro-apoptotic caspases, autophagy regulated by autophagy-related proteins, and necroptosis controlled by the RIPK/MLKL axis are representative of neural cell death occurred during AD. Necroptosis causes the release of cellular components, contributing to the pro-inflammatory environment in the AD brain. Inordinately high levels of neural cell death and pro-inflammatory events lead to the production of pro-inflammatory cytokines and feed-forward hyper neuroinflammation. Thus, neural cell death and neuroinflammation cause synaptic dysfunction and memory deficits in the AD brain. In this review, we briefly introduce the mechanisms of neural cell death and neuroinflammation observed in the AD brain. Combined with a typical strategy for targeting Aß and tau, regulation of neural cell death and neuroinflammation may be effective for the amelioration of AD pathologies.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Doenças Neuroinflamatórias , Peptídeos beta-Amiloides/metabolismo , Morte Celular , Inflamassomos/metabolismoRESUMO
Sedentary lifestyles and evolving work environments have created challenges for global health and cause huge burdens on healthcare and fitness systems. Physical immobility and functional losses due to aging are two main reasons for noncommunicable disease mortality. Smart electronic textiles (e-textiles) have attracted considerable attention because of their potential uses in health monitoring, rehabilitation, and training assessment applications. Interactive textiles integrated with electronic devices and algorithms can be used to gather, process, and digitize data on human body motion in real time for purposes such as electrotherapy, improving blood circulation, and promoting wound healing. This review summarizes research advances on e-textiles designed for wearable healthcare and fitness systems. The significance of e-textiles, key applications, and future demand expectations are addressed in this review. Various health conditions and fitness problems and possible solutions involving the use of multifunctional interactive garments are discussed. A brief discussion of essential materials and basic procedures used to fabricate wearable e-textiles are included. Finally, the current challenges, possible solutions, opportunities, and future perspectives in the area of smart textiles are discussed.
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Ti3C2Tx MXene, a two-dimensional transition metal carbide, has attracted substantial interest due to its unique physical properties and a wide range of potential applications. Although the properties of devices using MXene have been substantially enhanced in recent years, it is not fully understood how the oxygen concentration in Ti3AlC2 MAX affects oxide formation in Ti3C2-based MXene nanosheets and their fundamental properties. To this end, we compared two types of MAX phases: MAX with low oxygen content (LO-MAX) and MAX synthesized by a conventional process. Since the conventional MAX synthesis employs metal (Ti) as a primary material, it is referred to as metal-based MAX (MB-MAX) from here. The oxygen content of the LO-MAX was only 0.56 wt %, which was about 20% compared to that of MAX synthesized using conventional methods. We compared the properties of MXene nanosheets prepared from the LO-MAX with MXene nanosheets obtained from the MB-MAX. Microscopic and chemical analyses revealed smooth and wrinkle-free morphology and small amounts of oxygen in MXene nanosheets prepared from LO-MAX (LO-MXene). The LO-MXene nanosheet film exhibited an exceptionally high conductivity of 10,540 S/cm and an ultralow surface roughness of 1.7 nm, which originated from inhibited surface oxide formation. Moreover, the inhibition of oxide formation strengthened the function of -O or -OH groups on the surface of MXene, thereby facilitating strong hydrogen bonding to the polymer with hydroxyl groups. To clearly reveal these properties, we prepared a pressure sensor by coating these MXene nanosheets on nylon/polyester fibers. The fabricated sensor exhibited a high sensitivity of up to 85.6/kPa and excellent stretch stability and reliability. These results clearly revealed that lowering the oxygen content in MAX can make a decisive contribution to improving the fundamental properties of MXene nanosheets prepared therefrom.
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BACKGROUND: The representative symptom of Alzheimer's Disease (AD) has mainly been mentioned to be misfolding of amyloid proteins, such as amyloid-beta (Aß) and tau protein. In addition, the neurological pathology related to neuroinflammatory signaling has recently been raised as an important feature in AD. Currently, numerous drug candidates continue to be investigated to reduce symptoms of AD, including amyloid proteins misfolding and neuroinflammation. OBJECTIVE: Our research aimed to identify the anti-AD effects of two chemical derivatives modified from cromoglicic acid, CNU 010 and CNU 011. METHODS: CNU 010 and CNU 011 derived from cromoglicic acid were synthesized. The inhibitory effects of Aß and tau were identified by thioflavin T assay. Moreover, western blots were conducted with derivates CNU 010 and CNU 011 to confirm the effects on inflammation. RESULTS: CNU 010 and CNU 011 significantly inhibited the aggregation of Aß and tau proteins. Moreover, they reduced the expression levels of mitogen-activated protein (MAP) kinase and nuclear factor kappa-light-chain-enhancer of activated B cells (NF- κB) signaling proteins, which are representative early inflammatory signaling markers. Also, the inhibitory effects on the lipopolysaccharide (LPS)-induced cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) expression referring to late inflammation were confirmed. CONCLUSION: Our results showing multiple beneficial effects of cromolyn derivatives against abnormal aggregation of amyloid proteins and neuroinflammatory signaling provide evidence that CNU 010 and CNU 011 could be further developed as potential drug candidates for AD treatment.
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Doença de Alzheimer , Cromolina Sódica , Humanos , Cromolina Sódica/efeitos adversos , Doenças Neuroinflamatórias , Proteínas Amiloidogênicas/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , NF-kappa B/metabolismo , Inflamação/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Microglia/metabolismoRESUMO
Alzheimer's disease (AD) is a neurodegenerative disease characterized by severe brain damage and dementia. There are currently few therapeutics to treat this disease, and they can only temporarily alleviate some of the symptoms. The pathogenesis of AD is mainly preceded by accumulation of abnormal amyloid beta (Aß) aggregates, which are toxic to neurons. Therefore, modulation of the formation of these abnormal aggregates is strongly suggested as the most effective approach to treat AD. In particular, numerous studies on natural products associated with AD, aiming to downregulate Aß peptides and suppress the formation of abnormal Aß aggregates, thus reducing neural cell death, are being conducted. Generation of Aß peptides can be prevented by targeting the secretases involved in Aß-peptide formation (secretase-dependent). Additionally, blocking the intra- and intermolecular interactions of Aß peptides can induce conformational changes in abnormal Aß aggregates, whereby the toxicity can be ameliorated (structure-dependent). In this review, AD-associated natural products which can reduce the accumulation of Aß peptides via secretase- or structure-dependent pathways, and the current clinical trial states of these products are discussed.
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Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Produtos Biológicos/farmacologia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Produtos Biológicos/química , Descoberta de Drogas , Humanos , Terapia de Alvo Molecular , Agregados Proteicos/efeitos dos fármacos , Conformação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
A redox-neutral C2-selective methylation of heterocyclic N-oxides with sulfonium ylides is described herein. This report presents unprecedented findings for the utility of sulfonium ylides as the methylation source of N-heterocycles beyond the Corey-Chaykovsky reaction. Intriguingly, pyrrolidine plays a significant role in minimizing the reductive C2-methylation process. This method is characterized by its mild conditions, simplicity, and excellent site selectivity. The applicability of the developed protocol is showcased by the late-stage methylation and sequential transformations of complex drug molecules.
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Most photodetectors developed to date essentially measure photocurrents induced by the generation and separation of electron-hole pairs in semiconductors during irradiation. Although the above light detection method is well established, highly sensitive, and applicable to a broad range of semiconductor materials, it requires the presence of a stable and direct contact between the semiconductor and the electrode for accurate photocurrent measurements. In turn, this prerequisite necessitates the use of various costly processes for device fabrication (e.g., photolithography and vacuum deposition of semiconductors/metals) and complicates the development of flexible devices. Herein, inspired by the fact that the dielectric properties of certain materials can be changed by light irradiation, we dispersed ZnS/Cu semiconducting particles in poly(vinyl butyral) to prepare a free-standing composite film and formed two layers of Ag nanowire electrodes on both sides of the cured composite to fabricate a photodetector of a completely new type. The developed device exhibited a capacitance very sensitive to irradiation with light of a specific wavelength and additionally featured the advantages of simple structure/operation mechanism, mechanical flexibility, and transparency, not showing any signs of performance deterioration even after severe damage.