Search

Artificial synaptic devices (ASDs) are attracting widespread attention as highly promising components for use in complex neuromorphic systems, playing crucial roles in addressing the challenges posed by the conventional von Neumann architecture. However, the instabilities of ASDs in high‐temperature environments diminish the reliabilities of the device performances, significantly inhibiting their practical application. Herein, a highly reliable 2D MoS2/GaPS4 ASD that maintains its functionality even after exposure to 400 °C is proposed. Moreover, due to the enhanced charge‐trapping effect of the GaPS4 layer, the memory window expands from an initial 42 to 55 V, accompanied by a substantial on/off ratio of 105, low off‐leakage current of 10−11 A, and high number of endurance cycles (103). The device effectively simulates various biological synaptic functions via electric and light stimulation. Notably, the high electric and light paired‐pulse facilitation indices suggest an exceptional synaptic performance. The findings introduce a novel approach to high‐temperature neuromorphic applications via defect engineering. [ABSTRACT FROM AUTHOR]

This article reports a novel lead‐free phase‐transition material (C8H10ClN)2SnCl6 (1), which undergoes a high‐temperature phase change at close to 377 K. The multi temperature powder X‐ray diffraction (PXRD) also confirmed the phase transition occurred in compound 1. Significantly, compound 1 produces light emission at 452 nm. Variable temperature fluorescence studies indicate that the spectral emission maximum of compound 1 remains substantially fixed at 452 nm with increasing temperatures, implying the presence of a certain degree of photoluminescence stability in compound 1. Furthermore, compound 1 is characterized by exceptional semiconductor attributes, possessing a band gap of 3.76 eV. This pioneering study presents an innovative option for optimizing the growth and practical implementation of Sn (IV)‐based organic‐inorganic hybrid perovskite phase‐transition materials, and offers a strategic avenue to create novel lead‐free, eco‐friendly materials. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid metal halides for high-temperature phase transition have become increasingly popular owing to their wide operating temperature range in practical applications, e.g., energy storage, permittivity switches and opto-electronic devices. This paper describes the subtle assembly of two new hybrid perovskite crystals, [Cl-C6H4-(CH2)2NH3]2CdX4 (X = Br 1; Cl 2), undergoing high-T reversible phase transformations around 335 K/356 K. Differential scanning calorimetry (DSC), differential thermal analysis (DTA) and VT PXRD tests uncover their reversible first-order phase transition behaviors. Furthermore, the compounds exhibit switchable dielectricity near T, making them potential dielectric switching materials. Hirshfeld surface analysis well discloses a distinct difference in hydrogen-bonding interaction between 1 and 2. UV spectra and computational analysis demonstrate that the compounds are a type of direct-band-gap semiconductor. This research will contribute an effective approach to the structure and development of multifunctional molecular hybrid crystals. [ABSTRACT FROM AUTHOR]

A new flavonoid, saffloflavone , along with six known compounds, kaempferol-3-O-rutinoside, kaempferol-3-O-sophoroside, quercetin-3-O-β-d-glucoside, quercetin-7-O-β-d-glucoside, luteolin-7-O-β-d-glucoside and kaempferol 3-O-β-d-glucoside were isolated from the flowers of Carthamus tinctorius L. All the structures were determined by interpretation of their spectroscopic data. The cardioprotective effects of all the isolates against oxidative stress of H9c2 cells induced by H2O2 were investigated. The results showed that compounds 4–6 exhibited protective effects against of H9c2 cells injury induced by H2O2. [ABSTRACT FROM AUTHOR]

A new quinic acid derivative (1) along with seven known compounds (2–8) were isolated from the fruit of Gardenia jasminoides J.Ellis. All the structures of the isolated compounds were elucidated on the basis of the analysis of multiple spectroscopic data. The α-glucosidase inhibitory effects of the isolated compounds were investigated. The results showed that compounds 1–3, 6, and 8 have moderate α-glucosidase inhibitory activities. [ABSTRACT FROM AUTHOR]

A new amide, named rehmagluamide (1), and a new hydroxycinnamic acid derivative, named nepetoidin F (2), together with six known compounds, 2′-O-methyluridine (3), puroglutamic acid (4), biliverdic acid (5), peterolactam (6), nicotinic acid (7), nicotinamide (8), were isolated from the fresh roots of Rehmannia glutinosa. All the structures of compounds were identified by the interpretation of their spectroscopic data and comparison with those reported in the literatures. The protective effects of compounds 1–7 on normal rat kidney tubule epithelioid (NRK-52e) cells injury induced by LPS were investigated. The results indicated that compounds 1, 2, and 7 exhibited protective effects against LPS-induced NRK 52e cells injury. [ABSTRACT FROM AUTHOR]

Two new norsesquiterpenoids, dioscopposin A (1) and dioscopposin B (2), as well as 21 known compounds (3–23) were isolated from the stems and leaves of Dioscorea oppositifolia L. Their structures were elucidated by detailed analysis of comprehensive spectroscopic data. The absolute configurations were deduced by the comparison of experimental and calculated electronic circular dichroism spectra. Estrogenic activity of all the isolated compounds were evaluated using MCF-7 cells proliferation assay and compounds 2, 3, 7, 13, 15, 16, 18 and 21 exhibited proliferation activity. [ABSTRACT FROM AUTHOR]

Floating-gate transistors (FGTs), considered the most promising structure among three-terminal van der Waals (vdW) synaptic transistors, possess superiorities in improved data retention, excellent endurance properties, and multibit storage capacity, thereby overcoming the von Neumann bottleneck in conventional computing architectures. However, the dielectric layer in FGT devices typically depends on atomic layer deposition or mechanically transferred insulators, posing several challenges in terms of device compatibility, manufacturing complexity, and performance degradation. Therefore, it is crucial to discover dielectrics compatible with two-dimensional (2D) materials for further simplifying FGT structures and achieving optimal performance. Here, we present a controllable and reliable oxidation process to convert the 2D semiconductor ZrS 2 into its native oxide ZrO x and combine ZrO x /ZrS 2 with the MoS 2 channel to form MoS 2 /ZrO x /ZrS 2 FGT, which exhibits a high on/off ratio of 10 7 , a wide memory window of 101 V, a long retention time of 10 3 s, a large storage capacity of 7 bits, an excellent PPF index of 269.4%, and low power consumption of 5 pJ. Under photoelectric stimulation, the device stimulates various biological synapse behaviors, including associative memory function and retina-like adaptation. In particular, the device achieves information storage and erasure under solely optical stimulation, exhibiting high consistency with synaptic weight modulation in optogenetics and outstanding optoelectronic storage performance. These results suggest that our work provides a novel and effective approach for simplifying FGT structures and enhancing their performance, holding significant potential for application in next-generation multifunctional memory devices and systems.

Switchable materials have gained significant attention due to their potential applications in data storage, sensors, and switching devices. Two-dimensional (2D) hybrid perovskites have demonstrated promising prospects for designing switchable materials, where the dynamic motion of the organic components coupled with the distortion of the inorganic framework provides the driving force for triggering multifunctional switchable properties. Herein, through the H/F substitution strategy, we report a polar 2D hybrid lead-based perovskite, (4,4-DCA) 2 PbBr 4 (4,4-DCA = 4,4-difluorocyclohexylammonium) ( 1 ), which exhibits dual-stable behavior in a dielectric and second harmonic generation (SHG) response during the reversible phase transition process near the high Curie temperature T c ∼ 409 K. The phase transition temperature is significantly increased by 41 K compared to the corresponding non-fluorinated (CHA) 2 PbBr 4 (CHA = cyclohexylammonium). Remarkably, the material shows rare broad-band yellow emission under UV excitation, attributed to the induction of self-trapped exciton emission by the distortion of the [PbBr 6] 4- octahedra, as confirmed by the first-principles analysis. 1 also exhibited ferroelectricity with a saturation polarization value and a small coercive field. This study provides a new insight into the modification of multifunctional switchable materials through the H/F substitution strategy.

Aim: To investigate the alleviation of scutellarein (SN) against inner blood-retinal-barrier (iBRB) dysfunction in microglia cells stimulated by hyperglycemia and to elucidate the engaged mechanism., Methods: Microglia BV2 cells were stimulated by using 25 mmol/L D-glucose. The same concentration of mannitol (25 mmol/L) was applied as an isotonic contrast. Real-time PCR, Western-blot assay and immunofluorescence staining assay was performed. The dysfunction of iBRB in vitro was detected by using transendothelial electrical resistance (TEER) assay. Additionally, the leakage of fluorescein isothiocyanate (FITC)-conjugated dextran (70 kDa) was detected., Results: SN abrogated microglia BV2 cells activation and reduced the phosphorylated activation of extracellular signal-regulated protein kinase (ERK)1/2. SN also decreased the transcriptional activation of nuclear factor κB (NFκB) and the elevated expression of tumor necrosis factor α (TNFα), interleukin (IL)-6 and IL-1β in BV2 cells treated with D-glucose (25 mmol/L). SN attenuated iBRB dysfunction in human retinal endothelial cells (HRECs) or choroid-retinal endothelial RF/6A cells when those cells were treated with TNFα, IL-1β or IL-6, or co-cultured with microglia cells stimulated by D-glucose. Moreover, SN restored the decreased protein expression of tight junctions (TJs) in TNFα-treated HRECs and RF/6A cells., Conclusion: SN not only alleviate iBRB dysfunction via directly inhibiting retinal endothelial injury caused by TNFα, IL-1β or IL-6, but also reduce the release of TNFα, IL-1β and IL-6 from microglia cells by abrogating hyperglycemia-mediated the activation of microglia cells., (International Journal of Ophthalmology Press.)