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As a new type of semiconductor memory device, memristors receive wide attention because of their ability to realize multilevel memory and synapse-like learning. However, memristors made of traditional materials often demonstrate dispersion and unstable switching. Ferroelectric memristors can solve this problem and realize the regulation of synaptic plasticity. Herein, memristors based on Hf0.5Zr0.5O2 are fabricated on Si substrates. The I-Vcurve shows that the turn-on voltage of the device is lower for Hf0.5Zr0.5O2 film than for other compositions in HfxZr1-xOy films, and the ratio of ROFF/ RON can reach 104, implying excellent device performance. Furthermore, the train of pulse with different parameters can influence the modulation of device conductance. Also, the synaptic plasticity behavior of the device is studied. These results lay the foundation for the development of ferroelectric thin films with neuron-like artificial synapses. [ABSTRACT FROM AUTHOR]

Selected geological data on Early Cretaceous strata, structures, magmatic plutons and volcanic rocks from the Kunlun to Himalaya Mountains reveal a new view of the Early Cretaceous paleo-tectonics and the related geodynamic movement of the Tibetan Plateau. Two major paleo-oceans, the Mid-Tethys Ocean between the Qiangtang and Lhasa blocks, and the Neo-Tethys Ocean between the Lhasa and Himalayan blocks, existed in the Tibetan region in the Early Cretaceous. The Himalayan Marginal and South Lhasa Seas formed in the southern and northern margins of the Neo-Tethys Ocean, the Central Tibet Sea and the Qiangtang Marginal Sea formed in the southern and northern margins of the Mid-Tethys Ocean, respectively. An arm of the sea extended into the southwestern Tarim basin in the Early Cretaceous. Early Cretaceous intensive thrusting, magmatic emplacement and volcanic eruptions occurred in the central and northern Lhasa Block, while strike-slip formed along the Hoh-Xil and South Kunlun Faults in the northern Tibetan region. Early Cretaceous tectonics together with magmatic K2O geochemistry indicate an Early Cretaceous southward subduction of the Mid-Tethys Oceanic Plate along the Bangoin-Nujiang Suture which was thrust ∼87 km southward during the Late Cretaceous-Early Cenozoic. No intensive thrust and magmatic emplacement occurred in the Early Cretaceous in the Himalayan and southern Lhasa Blocks, indicating that the spreading Neo-Tethys Oceanic Plate had not been subducted in the Early Cretaceous. To the north, terrestrial basins of red-beds formed in the Hoh-Xil, Kunlun, Qilian and the northeastern Tarim blocks in Early Cretaceous, and the Qiangtang Marginal Sea disappeared after the Qiangtang Block uplifted in the late Early Cretaceous. [ABSTRACT FROM AUTHOR]

Ginkgo biloba extract (EGb761) has been shown to be neuroprotective; however, the mechanism by which EGb761 mediates neuroprotection remains unclear. We hypothesized that the neuroprotective effect of EGb761 is mediated by inhibition of cytosolic phospholipase A2 (cPLA2), an enzyme that is known to play a key role in mediating secondary pathogenesis after acute spinal cord injury (SCI). To determine whether EGb761 neuroprotection involves the cPLA2 pathway, we first investigated the effect of glutamate and hydrogen peroxide on cPLA2 activation. Results showed that both insults induced an increase in the expression of phosphorylated cPLA2 (p-cPLA2), a marker of cPLA2 activation, and neuronal death in vitro. Such effects were significantly reversed by EGb761 administration. Additionally, EGb761 significantly decreased prostaglandin E2 (PGE2) release, a downstream metabolite of cPLA2. Moreover, inhibition of cPLA2 activity with arachidonyl trifluromethyl ketone improved neuroprotection against glutamate and hydrogen peroxideinduced neuronal death, and reversed Bcl-2/Bax ratio; notably, EGb761 produced greater effects than arachidonyl trifluromethyl ketone. Finally, we showed that the extracellular signal-regulated kinase 1/2 signaling pathway is involved in EGb761's modulation of cPLA2 phosphorylation. These results collectively suggest that the protective effect of EGb761 is mediated, at least in part, through inhibition of cPLA2 activation, and that the extracellular signal-regulated kinase 1/2 signaling pathway may play an important role in mediating the EGb761's effect. [ABSTRACT FROM AUTHOR]

An open-label, randomized, 2-sequence, 4-period crossover (7-day washout period between treatment), replicate design study was conducted in 37 healthy subjects to assess intersubject and intrasubject variabilities in the peak (Cmax) and total (AUC) exposures to 2 oral antidiabetic drugs, pioglitazone and glimepiride, after single doses of 30 mg pioglitazone and 4 mg glimepiride, given under fasted state, as commercial tablets coadministered or as a single fixed-dose combination tablet. Variabilities for AUC∞ for coadministered and fixed-dose combination treatments were similar: 16% to 19% (intra) and 23% to 25% (inter) for pioglitazone and 18% to 19% (intra) and 29% to 30% for glimepiride (inter, excluding 1 poor metabolizer). Fixed-dose combination/ coadministered least squares mean ratios of =0.86 and the 90% confidence intervals of these ratios for pioglitazone and glimepiride of between 0.80 and 1.25 for Cmax, AUClqc, and AUC∞ met the bioequivalency standards. Gender analysis showed that women showed mean of 16% and 30% higher exposure than men for glimepiride (excluding1 poor metabolizer) and pioglitazone, respectively. There was considerable overlapping in the AUC∞ values, making genderdependent dosing unnecessary. Patients taking pioglitazone and glimepiride as cotherapy may replace their medication with a single fixed-dose combination tablet containing these 2 oral antidiabetic drugs. [ABSTRACT FROM AUTHOR]

Accurately forecasting regional distributed photovoltaic (DPV) power is crucial in mitigating the negative impact of high DPV penetration on the reliability and resilience of the distribution network. However, most of the current photovoltaic power forecasting methods suffer from two key problems: (1) ignoring the asymmetric influence relationship among DPV sites; (2) lack of consideration of dynamic spatiotemporal correlation among DPV sites. As a result, these methods are unable to fully adapt to the characteristics of DPV, making it challenging to directly apply the existing forecasting methods to improve the accuracy of DPV power forecasting. To conquer this limitation, a dynamic directed Graph Convolution Neural Network (DDGCN) is applied to regional DPV ultra‐short‐term power forecasting. Unlike the conventional Graph Convolution Neural Network (GCN) based forecasting methods, the proposed method improves GCN to process the directed graph. On this basis, to capture the dynamic and directed adjacency relationship among graph nodes, a temporal attention mechanism is proposed and combined with the directed GCN model. In this way, the dynamic and asymmetric/directed relationships among DPV sites can be taken into account. It is worth noting that the DPVs' adjacency relationship can be constructed without any prior knowledge by end‐to‐end model training. The simulation experiment proves that the prediction accuracy can be further improved by taking into account the dynamic directed relationship among the sites via a real DPV power dataset. [ABSTRACT FROM AUTHOR]

The title complex, [Cu2(C2O4)(C12H8N2)2(H2O)2](NO3)2·2H2O, is a centrosymmetric oxalate-bridged binuclear CuII complex with an inversion center located at the mid-point of the C—C bond of the bridging oxalate ligand. The Cu atom has five-coordinate square-pyramidal geometry. A network of O—H⋯O hydrogen bonds helps to consolidate the crystal packing. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, μ-2-hydroxy­butane­dioato-1κ2 O4, O4′:2κ3 O1, O2, O4-nitrato-2κ O-tris­(1,10-phen­anthroline)-1κ4 N, N′;2κ2 N, N′-dicopper(II) nitrate tetra­hydrate, [Cu2(C4H3O5)(NO3)(C12H8N2)3](NO3)·4H2O, contains an unsymmetrical dinuclear copper complex with Cu(phen)2 and Cu(phen)(NO3) moieties (phen is 1,10-phenanthroline) bridged by a malate (2-hydroxy­butane­dioate) ligand, which acts as a double-bridging and tetra­dentate ligand. As a result of this double-bridging action, especially the direct coordination of the O atom of one carboxyl­ate group of malate to the two Cu atoms, the Cu⋯Cu distance is only 4.199 (1) Å and the two phen planes are roughly parallel [the shortest inter­planar distance is 3.28 (1) Å], exhibiting an obvious intra­molecular π–π stacking inter­action. [ABSTRACT FROM AUTHOR]

This study deals with the fault-tolerant control problem for a class of two independent wheeled mobile robot systems with actuator faults and unknown robot parameters. Partial loss of control effectiveness and bias-actuator faults are addressed without knowing eventually faulty information of actuators. Adaptive schemes are developed to estimate unknown faulty parameters of actuator faults and unknown robot parameters of viscous friction factor and driving gain. Then, the backstepping control technique is utilised to construct the state feed-back control strategy based on the adaptive estimations. By using the Lyapunov stability theory, it is shown that the forward speed and azimuthal angle of wheeled mobile robots can track the given trajectory asymptotically in the case of actuator faults and unknown parameters. The effectiveness of the proposed designs is illustrated via a mobile robot system. [ABSTRACT FROM AUTHOR]

We have compared the melanogenic activities of cultured melanocytes carrying two common TYR alleles as homozygous 192S-402R wild-type, heterozygous and homozygous variant. This includes assays of TYR protein, DOPAoxidase activity, glycosylation and temperature sensitivity of protein and DOPAoxidase levels. Homozygous wild-type strains on average had higher levels of TYR protein and enzyme activity than other genotypes. Homozygous 402Q/Q melanocytes produced significantly less TYR protein, displayed altered trafficking and glycosylation, with reduced DOPAoxidase. However, near wild-type TYR activity levels could be recovered at lower growth temperature. In a sample population from Southeast Queensland, these two polymorphisms were present on four TYR haplotypes, designated as WT 192S-402R, 192Y-402R and 192S-402Q with a double-variant 192Y-402Q of low frequency at 1.9%. Based on cell culture findings and haplotype associations, we have used an additive model to assess the penetrance of the ten possible TYR genotypes derived from the combination of these haplotypes. [ABSTRACT FROM AUTHOR]

Five new polycyclic Daphniphyllum alkaloids, macropodumines F (1) and G (2), 17-oxoyuzurimine (3), and macropodumines H (4) and I (5), were isolated from the leaves of D. macropodumMiq., collected in Sichuan Province, China. The structures and relative configurations of the new compounds – as well as of four known, related alkaloids – were elucidated on the basis of in-depth spectroscopic and mass-spectrometric analyses, by chemical derivatization, and by comparison of spectroscopic data with those of known compounds. [ABSTRACT FROM AUTHOR]

The organic moiety of the title compound, C11H18NO5P·2H2O, is zwitterionic. The crystal packing is stabilized by N—H⋯O and O—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]