Abstract
In the quest for emerging in-sensor computing, materials that respond to optical stimuli in conjunction with non-volatile phase transition are highly desired for realizing bioinspired ...neuromorphic vision components. Here, we report a non-volatile multi-level control of VO
2
films by oxygen stoichiometry engineering under ultraviolet irradiation. Based on the reversible regulation of VO
2
films using ultraviolet irradiation and electrolyte gating, we demonstrate a proof-of-principle neuromorphic ultraviolet sensor with integrated sensing, memory, and processing functions at room temperature, and also prove its silicon compatible potential through the wafer-scale integration of a neuromorphic sensor array. The device displays linear weight update with optical writing because its metallic phase proportion increases almost linearly with the light dosage. Moreover, the artificial neural network consisting of this neuromorphic sensor can extract ultraviolet information from the surrounding environment, and significantly improve the recognition accuracy from 24% to 93%. This work provides a path to design neuromorphic sensors and will facilitate the potential applications in artificial vision systems.
The management of
diagnostic reagents has always been a concern. This paper describes the application of SPD medical consumables fine management system in our hospital. Relying on the brand-new ...management mode, the whole process from supplier qualification certificate management,
diagnostic reagent procurement management, secondary warehouse management, and then to the use process traceability was realized. The monthly cost of
diagnostic reagents can be accurately counted, which effectively controls the cost of
diagnostic reagents.
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•CaP-PNCs can be synthesized by the green, removable starch template.•CaP-PNCs/starch complex can be preserved for months by freeze-drying technology.•α-Amylase triggers the on-site ...smart biomimetic mineralization.•CaP-PNCs are released after hydrolysis and transformed to enamel-like structures.•The release of CaP-PNCs simulates the protein-proteinase process in organism.
With the attention of biomineralization, calcium phosphate precursor phases regulated by different organic templates are synthesized and used as mineral sources for biomimetic mineralization. However, most of the organic templates have limited ability to stabilize calcium and phosphorus ions, or the selected templates have poor biocompatibility and irremovability, which make them difficult to co-exist in long-term stability and crystal transformation, and to achieve convenient and harmless clinical application. Herein, we propose a calcium phosphate prenucleation clusters (CaP-PNCs)/starch complex, which includes uniform-sized, separate, and homogeneously distributed amorphous calcium phosphate nanoclusters of about 1 nm. By means of freeze-drying and redissolution, the CaP-PNCs/starch complex can be converted between liquid and spongy solid without changing their morphology and amorphous phase, and the freeze-dried CaP-PNCs/starch complex can be stored at room temperature for at least 5 months. Imitating the mechanism of protein-protease controlled biomineralization in organisms, the CaP-PNCs/starch complex is mixed with α-amylase during application. Starch templates are removed by enzymolysis and CaP-PNCs can be released, thus triggering on-site biomimetic mineralization with enamel-like structures to repair tooth tissue defects (including enamel and dentin). CaP-PNCs/starch complex provides a smart mineral source supply for biomimetic mineralization and a new pathway for the design of biomimetic materials.
Biological nervous system outperforms in both dynamic and static information perception due to their capability to integrate the sensing, memory and processing functions. Reconfigurable neuromorphic ...transistors, which can be used to emulate different types of biological analogues in a single device, are important for creating compact and efficient neuromorphic computing networks, but their design remains challenging due to the need for opposing physical mechanisms to achieve different functions. Here we report a neuromorphic electrolyte-gated transistor that can be reconfigured to perform physical reservoir and synaptic functions. The device exhibits dynamics with tunable time-scales under optical and electrical stimuli. The nonlinear volatile property is suitable for reservoir computing, which can be used for multimodal pre-processing. The nonvolatility and programmability of the device through ion insertion/extraction achieved via electrolyte gating, which are required to realize synaptic functions, are verified. The device's superior performance in mimicking human perception of dynamic and static multisensory information based on the reconfigurable neuromorphic functions is also demonstrated. The present study provides an exciting paradigm for the realization of multimodal reconfigurable devices and opens an avenue for mimicking biological multisensory fusion.
We aimed this study at investigating the effect of nervonic acid on inflammation, and the potential mechanisms underlying the action of nervonic acid in experimental autoimmune encephalomyelitis ...(EAE) in C57BL/6 mice. During the study, we divided the mice into six groups: Model group, Control group, Drug group, and Nervonic acid groups(three different doses). This study observed the effects of nervonic acid (NA) on inflammatory infiltration and demyelination in the spinal cord of mice by Hematoxylin & Eosin (H&E) and Luxol Fast Blue (LFB). Combining biochemical evaluation and enzyme linked immunosorbent assay (ELISA) analysis was evaluated as the expression of antioxidant proteins and anti-inflammatory cytokines. Our results indicated that treatment with nervonic acid significantly inhibited the development and severity of experimental autoimmune encephalomyelitis in mice, accompanied by mitigating inflammatory infiltration and demyelination in the spinal cord of mice, and increased the expression of antioxidant proteins and anti-inflammatory cytokines. So, nervonic acid may be a promising candidate for intervention in multiple sclerosis and other autoimmune diseases as a potential new treatment option for treating multiple sclerosis.
High-performance active terahertz modulators as the indispensable core components are of great importance for the next generation communication technology. However, they currently suffer from the ...tradeoff between modulation depth and speed. Here, we introduce two-dimensional (2D) tellurium (Te) nanofilms with the unique structure as a new class of optically controlled terahertz modulators and demonstrate their integrated heterojunctions can successfully improve the device performances to the optimal and applicable levels among the existing all-2D broadband modulators. Further photoresponse measurements confirm the significant impact of the stacking order. We first clarify the direction of the substrate-induced electric field through first-principles calculations and uncover the unusual interaction mechanism in the photoexcited carrier dynamics associated with the charge transfer and interlayer exciton recombination. This advances the fundamental and applicative research of Te nanomaterials in high-performance terahertz optoelectronics.
An all-solid-state nitrate-selective electrode with the implementation of graphene as the ion-to-electron transducer was reported. The charge-transfer process was examined by electrochemical ...impedance spectroscope and the hydrophobic nature of the graphene film was characterized via the potentiometric water layer test. The analytical performance of the nitrate-selective electrode was investigated by the determination of nitrate in drinking water. The obtained results showed that graphene can significantly facilitate the ion-to-electron transducer and prevent the formation of water layer between the ion-selective membrane and the graphene layer. The fabricated nitrate-selective electrode displayed a Nernstian slope of 57.9mV per decade of nitrate concentration, a low detection limit of 3×10−5M and a rapid response time (within 10s) for concentration upon 10−4M. The determination of real samples indicated that the constructed nitrate-selective electrode was capable of monitoring nitrate in drinking water, providing a handy alternative for routine analysis.
Herein, the design of terahertz metasurface with symmetric T‐shaped resonators and the corresponding bright and dark modes are reported on. It is demonstrated that the dark mode evoked by breaking ...the structural symmetry is insensitive to the X‐polarized electric field and a typical electromagnetically induced transparency (EIT) effect is also observed in the numerical simulation when introducing a relatively low structural asymmetry where the dark and bright modes are modified to the same frequency. To explain the underlying mechanism, theoretical calculations based on the coupled Lorentz oscillator model are performed. In terms of the desirable fittings with the simulation results, it is confirmed that there exists the dark mode in the symmetric T‐shaped resonators and the coupling between the bright and dark modes enhanced by the structural–symmetry breaking is responsible for the observed EIT effect. It is shown in the results further that the structural asymmetry degree has close relation with the coupling strength resonance and can thereby greatly affect the oscillation resonance splitting in frequency that it is reflected by the change of the bandwidth of the transparency window. In addition, the experimental spectra showing the characteristic of broadband transparency window are explained by the excitation of the dark mode whose frequency deviates from the bright mode.
Herein, it is shown that the bright and dark modes that are excited respectively by X‐ and Y‐polarized THz wave coexist in T‐shaped resonators and reveal that the structural–symmetry breaking leads to an enhanced coupling between the bright and dark modes, which is responsible for the observed electromagnetically induced transparency (EIT) effect.
This paper investigates the electrocatalytic oxidation of (−)-epigallocatechin gallate (EGCG), the main monomer flavanol found in green tea, with a novel ionic liquid, n-octylpyridinium ...hexafluorophosphate (OPFP) carbon paste electrode (CPE). Due to the natural viscosity and high conductivity of OPFP, this novel OPFP-CPE exhibited very attractive properties, such as high stability and electrochemical reactivity, low background current, and wide electrochemical window. Therefore, this electrode is a very good alternative to traditional chemically modified electrodes because the electrocatalytic effect can achieved without any further electrode modification. Comparative experiments were carried out using CPE and a glassy carbon electrode (GCE). With OPFP-CPE, highly reproducible and well-defined cyclic voltammograms were obtained for EGCG. Under optimal experimental conditions, the peak current of differential pulse voltammetry (DPV) response increased linearly with EGCG concentration over the range of 5.0 × 10–7–1.25 × 10–5 M. The limit of detection (LOD) and the limit of quantification (LOQ) were 1.32 × 10–7 and 4.35 × 10–7 M, respectively. The method was applied to the determination of EGCG in green tea infusion samples, and the recovery of the spiked EGCG to the diluted (10-fold) tea extract was from 87.62 to 99.51%.
In addition to carrying and transmitting genetic material, some DNA molecules have specific binding ability or catalytic function. DNA with this special function is collectively referred to as ...functional DNA (fDNA), such as aptamer, DNAzyme and so on. fDNA has the advantages of simple synthetic process, low cost and low toxicity. It also has high chemical stability, recognition specificity and biocompatibility. In recent years, fDNA biosensors have been widely investigated as signal recognition elements and signal transduction elements for the detection of non-nucleic acid targets. However, the main problem of fDNA sensors is their limited sensitivity to trace targets, especially when the affinity of fDNA to the targets is low. To further improve the sensitivity, various nucleic acid signal amplification strategies (NASAS) are explored to improve the limit of detection of fDNA. In this review, we will introduce four NASAS (hybridization chain reaction, entropy-driven catalysis, rolling circle amplification, CRISPR/Cas system) and the corresponding design principles. The principle and application of these fDNA sensors integrated with signal amplification strategies for detection of non-nucleic acid targets are summarized. Finally, the main challenges and application prospects of NASAS integrated fDNA biosensing system are discussed.
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•Recent advances in non-nucleic acid target detection by fDNA sensors are reviewed.•The features of four nucleic acid signal amplification strategies are focused.•The trends of fDNA sensors integrated with signal amplification are discussed.
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