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Information processing and memorizing in the brain take place in a neural network consisting of neurons connected with each other by synapses. Meanwhile, the neural network is immersed in a common electrochemical environment with global parameters regulating the overall functions, which is barely discussed in neuromorphic devices. In this study, organic/inorganic hybrid transistors with sodium alginate as the gate dielectric layer and indium tin oxide as the channel were successfully prepared. We have not only simulated the basic properties of synapses in a single device, but, on top of that, also simulated the global regulation of information processing in the brain due to the incorporation of global grids, achieving excitatory and inhibitory synaptic weight. Moreover, the construction of a 3 × 3 synaptic array enables image learning and memorizing functions. These results demonstrate the significant advantages of electrolyte-gated transistors in enabling complex neural network connectivity and offer a promising opportunity for future artificial synapses. [ABSTRACT FROM AUTHOR]

Nickel diselenide (NiSe2) microspheres were synthesized using a chemical vapor deposition (CVD) method, and their nonlinear optical properties were investigated. The prepared NiSe2 exhibits good nonlinear characteristics, demonstrating a high modulation depth and a low saturation intensity. Then the NiSe2 was used as a saturable absorber device and integrated into a 1.5 μm erbium-doped fiber laser to generate Q-switched pulse. By optimizing the cavity dispersion and adjusting the polarization state within the cavity, the single pulse tunable Q-switched pulse, Q-switched mode-locking pulse and quasi-mode-locked pulse based on NiSe2 saturable absorber are realized. Among them, the signal-to-noise ratio of the quasi-mode-locked pulse is as high as 68 dB, which proves that the resulting pulse has high stability. The findings of this study suggest that NiSe2 SA devices have the potential to be developed as highly efficient candidates for ultrafast photonics and can find extensive applications in nonlinear optical fields. [ABSTRACT FROM AUTHOR]

The influence of electrodes on antiferroelectricity and fatigue endurance of 15 nm thick Hf0.2Zr0.8O2 thin films has been studied by a metal–antiferroelectric–metal capacitor structure using TiN and W as electrodes. The W|Hf0.2Zr0.8O2|W capacitor shows significantly enhanced antiferroelectricity and better endurance compared to the capacitor using TiN as the electrode. Assisted by grazing incidence x-ray diffraction and scanning transmission electron microscopy, the different electrical properties are discussed based on the contents of different phases and the diffusion of oxygen from the thin film into electrodes. [ABSTRACT FROM AUTHOR]

The supercontinuum generation and manipulation of Airy-Gaussian pulses in a photonic crystal fiber with three zero-dispersion points are studied using the split-step Fourier method. Firstly, the spectral evolution of Airy-Gaussian pulses in four photonic crystal fibers with different barrier widths was discussed, and the optimal fiber was determined after considering the factors of width and flatness. By analyzing the mechanism of supercontinuum generation in photonic crystal fibers with single, double and three zero-dispersion points, it is found that the photonic crystal fiber with three zero-dispersion points have a larger spectral width due to the component of tunneling solitons. Then, the effects of four characteristic parameters (truncation factor a, distribution factor χ0, initial chirp C and central wavelength λ) on forming the supercontinuum spectrum of Airy-Gaussian pulses are analyzed in detail. The results show that the spectral width and energy intensity of the dispersive wave and tunneling soliton generation can be well controlled by adjusting the barrier width and initial parameters of the pulse. These research results provide a theoretical basis for generating and manipulating high-power mid-infrared supercontinuum sources. [ABSTRACT FROM AUTHOR]

Diabetic encephalopathy (DE) is one of the most prevalent chronic complications of diabetes mellitus (DM), with neither effective prevention nor proven therapeutic regimen. This study aims to uncover the potential dysregulation pattern of the neurotransmitters in a rat model of streptozotocin (STZ)-induced experimental DE. For that purpose, male Sprague- Dawley (SD) rats were treated with a single intraperitoneal injection of STZ. Cognitive performance was detected with the Morris water maze (MWM) test. Serum, cerebrospinal fluid (CSF), and brain tissues were collected to measure the levels of neurotransmitters. Compared with the control rats, the acetylcholine (ACh) levels in serum, CSF, hippocampus, and cortex were all significantly down-regulated as early as 6 weeks in the STZ treatment group. In contrast, the glutamate (Glu) levels were decreased in CSF and the hippocampus, but unaffected in the serum and cortex of STZ-treated rats. As for γ-aminobutyric acid (GABA), it was down-regulated in serum, but up-regulated in CSF, hippocampus, and the cortex in the STZ-treated group. The mRNA expressions of neurotransmitter-related rate limiting enzymes (including AChE, GAD1, and GAD2) and pro-inflammatory cytokines (including IL-1β and TNF-α) were all increased in the DE rats. Our data suggest that DM induces isoform-dependent and tissue-specific neurotransmitter abnormalities, and that neuroinflammation may underlay the nervous system dysfunction observed in the progression of DE. Key words: cognitive dysfunction, diabetic encephalopathy (DE), neurotransmitter, acetylcholine (ACh), glutamate (Glu), γ-aminobutyric acid (GABA), neuroinflammation, acetylcholinesterase (AChE), glutamate decarboxylase (GAD). L'encephalopathie diabetique (ED) est une des complications chroniques les plus frequentes du diabete sucre (DS) pour laquelle il n'existe pas de prevention efficace ni de modalites therapeutiques reconnues. L'etude presente vise a decouvrir le patron potentiel de deregulation des neurotransmetteurs dans un modele d'ED induite chez le rat par la streptozotocine (STZ). A cette fin, des rats males Sprague-Dawley (SD) ont recu une injection unique de STZ par voie intra-peritoneale. Le rendement cognitif a ete evalue par des tests en labyrinthe de Morris (LM). Le serum, le liquide cephalorachidien (LCR) et les tissus cerebraux ont ete recoltes afin de doser les neurotransmetteurs. Les niveaux d'acetylcholine (ACh) dans le serum, le LCR, l'hippocampe et le cortex des rats traites a la STZ etaient regules a la baisse aussitot qu'apres 6 semaines de traitement, comparativement aux rats controles. Par contre, les niveaux de glutamate (Glu) etaient diminues dans le LCR et l'hippocampe, mais ils n'etaient pas affectes dans le serum et le cortex des rats traites a la STZ. En ce qui concerne l'acide γ-aminobutirique (GABA), il etait regule a la baisse dans le serum mais regule a la hausse dans le LCR, l'hippocampe et le cortex des rats traites a la STZ. L'expression de l'ARNm d'enzymes liees aux etapes cinetiquement limitantes de la synthese des neurotransmetteurs (incluant AChE, GADi et GAD2) et de cytokines proinflammatoires (incluant IL-1β et TNF-α), etait diminuee chez les rats atteints d'ED. Les donnees des auteurs suggerent que le DS induit des anomalies des neurotransmetteurs dependantes de l'isoforme et specifiques aux tissus, et que la neuro-inflammation peut sous-tendre la dysfonction du systeme nerveux observee lors de la progression de l'ED. [Traduit par la Redaction] Mots-cles: dysfonction cognitive, encephalopathie diabetique (ED), neurotransmetteur, acetylcholine (ACh), glutamate (Glu), acide γ-aminobutirique (GABA), neuro-inflammation, acetylcholinesterase (AChE), glutamate decarboxylase (GAD)., Introduction Diabetes mellitus (DM) is one of the most devastating chronic systemic diseases. DM can damage several organs of the body; however, a less addressed and not well-recognized complication is [...]

Ferroelectric resistive switching (RS) devices with functional oxide electrodes allow controlled emergent phenomena at an interface. Here, we demonstrate RS polarity reversal due to ferroelectrically induced phase transition at a doped charge transfer insulator interface. For BiFeO3/Ca0.96Ce0.04MnO3 bilayers grown on a NdAlO3 substrate, by applying voltages to a Ca0.96Ce0.04MnO3 bottom electrode, the resistance changes from a high resistance state (HRS) to a low resistance state (LRS) during a positive voltage cycle (0 → 3 → 0 V), and from a LRS to a HRS during a negative voltage cycle (0 → −3 → 0 V). The RS polarity is completely opposite the expected RS behavior in ferroelectric heterostructures induced by polarization reversal. It is proposed that the unique resistance switching polarity is attributed to the band-filling controlled metal-insulator transition in a Ca0.96Ce0.04MnO3 film, triggered by ferroelectric based electrostatic doping. The results address the importance of ferroelectric field effect on the electronic properties of the interfacial system in ferroelectric/complex oxide-based resistive memory devices. [ABSTRACT FROM AUTHOR]