On critical Fujita exponents for the porous medium equation with a nonlinear boundary condition

AbstractWe establish the critical Fujita exponents for the solution of the porous medium equation ut=Δum, x∈R+N, t>0, subject to the nonlinear boundary condition −∂um/∂x1=up, x1=0, t>0, in multi-dimension

Aqueous extract of Aconitum carmichaelii Debeaux attenuates sepsis-induced acute lung injury via regulation of TLR4/NF-ΚB pathway

Purpose: To investigate the therapeutic effect of aqueous extract of Aconitum carmichaelii Debeaux (AEACD) on sepsis-induced acute lung injury (ALI), as well as explore the underlying mechanism of action. Methods: C57BL/6 mice were treated with AEACD by gavage (4.0 g/kg/day) for 5 days before cecal ligation and puncture (CLP) challenge. After 24 h, the pathological morphology of lung tissue and the biochemical parameters in bronchoalveolar lavage fluid (BALF) were determined by H&E staining and enzyme-linked immunosorbent assay (ELISA). Furthermore, the total protein content and lactate dehydrogenase (LDH) level of BALF, as well as the oxidative biomarkers (malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD)) were evaluated in the lung homogenates by ELISA assay. The levels of pro-inflammatory cytokines, TNFα, IL-1β, and IL-6, in lung tissue were measured by qRT-PCR or ELISA. Finally, key proteins in Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway in lung tissue were evaluated by western blot. Results: CLP challenge induced abnormal changes in the histological structures of lung tissue, lung wet-to-dry weight (W/D) ratio, protein content and LDH levels of BALF, which were remarkably reversed by AEACD. In addition, AEACD decreased MDA levels, and increased GSH levels and SOD activity in the lung tissue of CLP–treated mice (p < 0.05). Furthermore, AEACD attenuated the CLP challengeinduced upregulation of TNFα, IL-1β, and IL-6. Finally, AEACD inactivated TLR4/NF-κB pathway by upregulating IκBα and downregulating TLR4 and phosphorylated-p65 levels. Conclusion: AEACD administration protects mice against sepsis-induced ALI through the regulation of oxidative stress and inflammatory responses in lung tissues. The underlying mechanism occurs by inhibiting TLR4/NF-κB signaling pathway. Keywords: Aconitum carmichaelii Debeaux, Acute lung injury, Sepsis, TLR4, NF-κ

Asynchronous Spiking Neural P Systems with Multiple Channels and Symbols

Spiking neural P systems (SNP systems, in short) are a class of distributed parallel computation systems, inspired from the way that the neurons process and communicate information by means of spikes. A new variant of SNP systems, which works in asynchronous mode, asynchronous spiking neural P systems with multiple channels and symbols (ASNP-MCS systems, in short), is investigated in this paper. There are two interesting features in ASNP-MCS systems: multiple channels and multiple symbols. That is, every neuron has more than one synaptic channels to connect its subsequent neurons, and every neuron can deal with more than one type of spikes. The variant works in asynchronous mode: in every step, each neuron can be free to fire or not when its rules can be applied. The computational completeness of ASNP-MCS systems is investigated. It is proved that ASNP-MCS systems as number generating and accepting devices are Turing universal. Moreover, we obtain a small universal function computing device that is an ASNP-MCS system with 67 neurons. Specially, a new idea that can solve ``block'' problems is proposed in INPUT modules

Formation of Ideal Rashba States on Layered Semiconductor Surfaces Steered by Strain Engineering

Spin splitting of Rashba states in two-dimensional electron system provides a promising mechanism of spin manipulation for spintronics applications. However, Rashba states realized experimentally to date are often outnumbered by spin-degenerated substrate states at the same energy range, hindering their practical applications. Here, by density functional theory calculation, we show that Au one monolayer film deposition on a layered semiconductor surface beta-InSe(0001) can possess "ideal" Rashba states with large spin splitting, which are completely situated inside the large band gap of the substrate. The position of the Rashba bands can be tuned over a wide range with respect to the substrate band edges by experimentally accessible strain. Furthermore, our nonequilibrium Green's function transport calculation shows that this system may give rise to the long-sought strong current modulation when made into a device of Datta-Das transistor. Similar systems may be identified with other metal ultrathin films and layered semiconductor substrates to realize ideal Rashba states.Comment: Nano Letters 201