Search

Layered thio- and seleno-phosphate ferroelectrics, such as CuInP2S6, are promising building blocks for next-generation nonvolatile memory devices. However, because of the low Curie point, the CuInP2S6-based memory devices suffer from poor thermal stability (<42 °C). Here, exploiting the electric field-driven phase transition in the rarely studied antiferroelectric CuCrP2S6 crystals, we develop a nonvolatile memristor showing a sizable resistive-switching ratio of ~ 1000, high switching endurance up to 20,000 cycles, low cycle-to-cycle variation, and robust thermal stability up to 120 °C. The resistive switching is attributed to the ferroelectric polarization-modulated thermal emission accompanied by the Fowler–Nordheim tunneling across the interfaces. First-principles calculations reveal that the good device performances are associated with the exceptionally strong ferroelectric polarization in CuCrP2S6 crystal. Furthermore, the typical biological synaptic learning rules, such as long-term potentiation/depression and spike amplitude/spike time-dependent plasticity, are also demonstrated. The results highlight the great application potential of van der Waals antiferroelectrics in high-performance synaptic devices for neuromorphic computing.Layered thio- and seleno-phosphate ferroelectrics show promise for next-generation memory but have thermal stability issues. Using the electric field-driven phase transition in antiferroelectric CuCrP2S6, the authors introduce a robust memristor, emphasizing the potential of van der Waals antiferroelectrics in advanced neuromorphic computing. [ABSTRACT FROM AUTHOR]

Time-dependent studies of pulsed inductively coupled Ar and Ar/CF 4 discharges are presented in this work. By using a time-resolved power diagnosis system, i.e., a Langmuir probe and a Hairpin probe, the temporal evolutions of input power and electron density are measured. In the initial pulse stage, the input power exhibits two peaks, which are related to the properties of the source and the plasma, respectively. In addition, an overshoot of the electron density is observed in the initial pulse stage at high powers (500–800 W) and low pressures (1–10 mTorr), and the overshoot becomes weaker by increasing pressure (10–80 mTorr) or decreasing input power (200–500 W). This can be explained by the dependence of the power transfer efficiency on pressure and input power, as well as the balance between the electron production and loss rates. When the power is turned off, the electron density and the input power exhibit a peak at the initial afterglow period, due to the release of charges from capacitors and inductors in the radio frequency power source. In Ar/CF 4 discharges, the plasma responds to the changes in the input power more quickly than in Ar discharges, so it takes a shorter time to reach the ionization equilibrium. This may be caused by more ionization channels, larger ionization cross section, and lower ionization thresholds in Ar/CF 4 plasmas. [ABSTRACT FROM AUTHOR]

To improve the electrical properties and temperature stability of (K,Na)NbO3 (KNN)-based ceramics, 0.964K0.40Na0.60Nb0.96Sb0.04O3-0.03Bi0.5Na0.5ZrO3-0.006BiFeO3-xZnF2 (KNNS-BNZ-BF-xZnF2, 0.005 ≤ x ≤ 0.030) lead-free ceramics were designed. The effect of ZnF2 content on microstructure and electrical behavior was mainly investigated. Through tuning chemical modifications, the enhancement of electrical properties (d33 ∼478 pC/N, kp ∼0.483, ɛr ∼2759, tan δ∼0.035, Pr ∼17.0 μC/cm2, and EC ∼7.02 kV/cm), large Suni (∼0.195% at 40 kV/cm; 0.235% at 75 kV/cm), and d33* (∼555 pm/V at 20 kV/cm; 488 pm/V at 40 kV/cm) can be obtained for x = 0.015. In addition, excellent strain stability (fluctuation is less than 19% at 25-125 °C) is realized in the ceramics, which is also superior compared to other KNN-based materials and some soft lead-based counterparts. We believe that this work can be beneficial to design lead-free piezoelectric materials with excellent temperature stability and high piezoelectricity. [ABSTRACT FROM AUTHOR]

Angiogenesis is a critical factor in tumor growth and metastasis, and microvessel density (MVD) was an important parameter for assessing vessels in tumors. However, radiologic assessment of tumor vascularity is not yet well established. In our study, we aimed at investigating the efficacy of contrast-enhanced ultrasonography (CEUS) in exploring the vascularity of the ovarian tumors or tumor-like lesions to assess the relationship between the parameters of the peak intensity (PI) and area under curve (AUC) on CEUS and MVD in ovarian masses. Compared to the contrast-enhanced ultrasound technique, conventional ultrasound shows limitation in differentiating benign and malignant ovarian tumors. The former is promising in improving the sensitivity of detecting small vessels and blood flow in ovarian tumors. Our results showed clear differences in enhancement patterns between benign and malignant ovary tumors or tumor-like lesions. The PI and AUC in the malignant tumors were significantly higher than those in the benign tumors or tumor-like lesions (p=0.001 and =0.01, respectively). The MVD was 43.1 ± 20.4 in the benign tumors or tumor-like lesions and was 65.3 ± 22.3 in the malignant ones (p= 0.01). In both the benign and malignant groups, the PI and AUC were correlated significantly with the MVD (r=0.595, p = 0.001; r =0.533, p = 0.003, respectively). The PI and AUC in CEUS can reflect the MVD in ovarin tumors. The PI and AUC of the ovarian masses in the contrast transvaginal sonography show significant correlation with the angiogenesis and may help in assessing tumor vascularity in ovarian masses.

In this paper, we first construct a microfluidic chemostat model for the growth of biofilms and planktonic populations with random dilution ratios and then investigate its dynamical behavior. Using the theory of monotone dynamical systems and the Multiplicative Ergodic Theorem, we show the existence of random attractors and stationary measures, and present Lyapunov exponents for the linearized cocycle with respect to the random model. Further on, if the top Lyapunov exponent is negative, we give the extinction of microbial populations, including the forward and pull-back trajectories. [ABSTRACT FROM AUTHOR]

Background Alcohol-induced hangover represents a significant, yet understudied, global hazard and a large socioeconomic burden. Objective The aim of this study was to investigate the effects of hydrogen on relieving drinking and hangover symptoms in 20 healthy volunteers. Methods In this pilot, randomized, double-blinded, placebo-controlled, matched, crossover interventional trial, participants were matched into pairs and randomly assigned. Study group 1 inhaled placebo air for 1 h, followed by drinking 100 mL liquor (40% alcohol) within 10 min, and then pure water. Study group 2 inhaled a mixture of hydrogen and oxygen gas for 1 h, followed by drinking 100 mL liquor within 10 min, and then hydrogen dissolved in water. On a second intervention day (crossover) ≥1 wk later, study-group subjects were switched to the opposite order. Breath alcohol concentration (BrAC), hangover severity, and cognitive scores were measured. Results The BrACs within the hydrogen group were significantly lower than those within the placebo group after 30 min, 60 min, and 90 min (P   <  0.05). The hydrogen group reported having fewer hangover symptoms compared with the placebo group (placebo: 77% of symptoms absent, 19.7% of mild symptoms, 2.7% of moderate symptoms, 0.7% of severe symptoms; hydrogen: 88.6% of symptoms absent, 10% of mild symptoms, 1.3% of moderate symptoms, 0% of severe symptoms; P   <  0.001). Hydrogen treatment improved cognitive testing scores (P   <  0.05), including attention and executive functions. Furthermore, consumption of hydrogen was negatively (β = −13.016; 95% CI: −17.726, −8.305; P   <  0.001) and female sex was positively (β = 22.611; 95% CI: 16.226, 28.997; P   <  0.001) correlated with increased BrACs. Likewise, the consumption of hydrogen was negatively (OR: 0.035; 95% CI: 0.007, 0.168; P   <  0.001) while female sex was positively (OR: 28.838; 95% CI: 5.961, 139.506; P   <  0.001) correlated with the severity of hangover symptoms. Conclusions Hydrogen decreases BrACs and relieves the symptoms of hangovers. This trial was registered at the China Clinical Trial Registry (http://www.chictr.org.cn/showproj.aspx?proj=58359) as ChiCTR2200059988. [ABSTRACT FROM AUTHOR]

Rhapontici Radix ethanol extract (RRE) is derived from the dried root of Rhaponticum uniflorum (L.) DC belonging to the Asteraceae family. RRE exhibits significant anti-inflammatory and antioxidant properties; however, the potential of RRE in mastitis treatment requires further investigation. This research was performed to examine the protective properties of RRE against mastitis and the mechanisms underlying the effects of RRE. RRE components were analyzed by HPLC-MS/MS and DPPH methods. Isochlorogenic acid B (ICAB) was obtained commercially. MTT assay was utilized to assess RRE or ICAB cytotoxicity in bovine mammary alveolar (MAC-T) cells. Immunohistochemistry were used to investigate the pathological alterations in mammary tissue. The protein levels of inflammatory cytokines and mediators were analyzed using ELISA, and the expression of MAPK and NF-κB signaling pathways, as well as p65 nuclear translocation, were analyzed through Western blotting and immunofluorescence techniques, respectively. Target proteins of RRE were screened by RNA-seq and tandem mass tag analyses. Protein interaction was revealed and confirmed using co-immunoprecipitation and CRISPR/Cas9-based knockdown and overexpression of target genes. ICAB was revealed as one of the main components in RRE, and it was responsible for 84.33% of RRE radical scavenging activity. Both RRE and ICAB mitigated the infiltration of T lymphocytes in the mammary glands of mice, leading to decreased levels of inflammatory mediators (COX-2 and iNOS) and cytokines (TNF-α, IL-6, and IL-1β) in lipopolysaccharide (LPS)-induced MAC-T cells. Furthermore, RRE and ICAB suppressed the LPS-induced phosphorylation of NF-κB inhibitor and p65, thereby impeding p65 nuclear translocation in mouse mammary glands and MAC-T cells. In addition, RRE and ICAB attenuated the LPS-triggered activation of c-Jun N-terminal kinase 1/2, p38, and extracellular regulated protein kinase 1/2. Importantly, co-treated with LPS and ICAB in MAC-T cells, an upregulation of G-protein coupled receptor 161 (GPR161) and transmembrane protein 59 (TMEM59) was observed; the interact between TMEM59 and was found, leading to inhibition of NF-κB activity and inflammatory cytokine production. ICAB is a prominent antioxidant in RRE. RRE and ICAB reduce mammary inflammation via MAPK and NF-κB pathways and the interaction between TMEM59 and GPR161 mediates the control of ICAB in NF-κB signaling. [Display omitted] [ABSTRACT FROM AUTHOR]