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The electronic structures and nonlinear optical (NLO) responses of eight triangle group‐VI transition metal dichalcogenides (TMDs) lateral‐core–shell heterostructures quantum dots (QDs) [MaX2MbX2 and MXa2MXb2; M (Ma, Mb) = Mo and W; X (Xa, Xb) = S and Se] have been explored by using quantum chemistry method. Frontier molecular orbital (FMOs) analyses indicate that the triangular frameworks with more active W and/or Se atoms at shell have smaller energy gaps than those with Mo and/or S atoms, and the active sites of the ultra‐small TMD heterostructures mainly locate at the edge and/or the corner of the frameworks. Generally speaking, active atoms at the shell are beneficial to the enhancement of the frequency‐dependent first hyperpolarizabilities compared with the active atoms in the cores. First hyperpolarizability density analyses show that the local contributions of the first hyperpolarizability in x direction is mainly located at the left and right corners, while that in y direction is mainly located at the bottom edge and top corner, confirming the important role that the shell of the TMDs lateral‐core–shell heterostructure QDs play in its NLO response. Further, the electronic transitions contributed to the SHG responses also occur at the shell of these triangular frameworks. [ABSTRACT FROM AUTHOR]

The interaction mechanism between displacement damage and ionization damage in SiO2 layer has been researched on gate-controlled lateral p-n-p transistor (GLPNP). The sequential irradiation experiments of 400-keV O ions with high dose rate $\gamma $ -rays were carried out, and the degradation and defect evolution results of the device were analyzed by the reciprocal change of current gain change, gate sweep (GS) curve, and deep level transient spectrum (DLTS) results. The results show that there is a negative direct synergistic effect between 400-keV O ions and Co- $60~\gamma $ -rays in GLPNP. At the same time, combined with the GS curve and DLTS results, it can be concluded that the displacement defects of 400-keV O ions in SiO2 layer of GLPNP transistors will capture the holes generated by Co- $60~\gamma $ -rays, thus forming a large number of positive oxide charges ($N_{\mathrm {ot}}$). These $N_{\mathrm {ot}}$ are like “space charge wall,” hindering the movement of protons and holes to the Si/SiO2 interface, and thus inhibiting the generation of interface trap ($N_{\mathrm {it}}$). Due to the decrease of $N_{\mathrm {it}}$ and the increase of positive $N_{\mathrm {ot}}$ , the damage of transistor is weakened. The experimental results show the effects of displacement damage on the ionization effect in SiO2 layer and, more important, provide direct evidence for the space charge model. [ABSTRACT FROM AUTHOR]

The bulk photovoltaic effect shift current (SC), a constant photocurrent generated by irradiating polar homogeneous non‐centrosymmetric materials has lately emerged as a possible option for next‐generation photovoltaic systems that may potentially overcome the Shockley–Queisser limits. The current work predicts gigantic and anisotropic SC with multiple peaks across a wide range of frequencies in pristine 2D monolayer α‐AsP and α‐NP based on first‐principle calculations. The dominant SC tensors components hosted by 2D monolayer α‐AsP and α‐NP are the in‐plane, and reaches peaks of −154 µАV−2, and 87 µАV−2, respectively, in the UV region. The SC magnitudes of the α‐AsP are not significantly affected by the spin‐orbital coupling, while in α‐NP, no such effect occurs. This study recommends new photovoltaic materials with strong SC peaks spread across the electromagnetic spectrum, largely within the UV region. [ABSTRACT FROM AUTHOR]

The widespread application of artificial neural networks has prompted researchers to experiment with field-programmable gate array and customized ASIC designs to speed up their computation. These implementation efforts have generally focused on weight multiplication and signal summation operations, and less on activation functions used in these applications. Yet, efficient hardware implementations of nonlinear activation functions like exponential linear units (ELU), scaled ELU (SELU), and hyperbolic tangent (tanh), are central to designing effective neural network accelerators, since these functions require lots of resources. In this paper, we explore efficient hardware implementations of activation functions using purely combinational circuits, with a focus on two widely used nonlinear activation functions, i.e., SELU and tanh. Our experiments demonstrate that neural networks are generally insensitive to the precision of the activation function. The results also prove that the proposed combinational circuit-based approach is very efficient in terms of speed and area, with negligible accuracy loss on the MNIST, CIFAR-10, and IMAGE NET benchmarks. Synopsys design compiler synthesis results show that circuit designs for tanh and SELU can save between ${\times 3.13\sim \times 7.69}$ and ${ {\times 4.45\sim \times 8.45}}$ area compared to the look-up table/memory-based implementations, and can operate at 5.14 GHz and 4.52 GHz using the 28-nm SVT library, respectively. The implementation is available at: https://github.com/ThomasMrY/ActivationFunctionDemo. [ABSTRACT FROM AUTHOR]

As a main cause of foodborne diseases, pathogenic bacteria have threatened the health and well-being of human communities. There is a need of fastness, accuracy and sensitivity in the method of detecting pathogenic bacteria. Classical signal amplification assays usually employ enzymes as biocatalysts to generate amplified signals, but the strict experimental conditions and complicated instruments restrict their application. In this work, we demonstrated an enzyme-free branched DNA (bDNA)-based signal amplification electrochemiluminescence (ECL) assay for ultrasensitive detection of pathogenic bacteria. Firstly, the capture probes and the amplification probes group were carefully designed by our research group. The detecting ECL signal of Staphylococcus aureus ( S. aureus ) was amplified by bDNA technique through the layer-by-layer signal amplification. The sensitivity was greatly improved by the use of multiple Ru(bpy) 3 2+ (TBR)-labeled ECL probes. Secondly, the whole process of the detection was carried out in the absence of enzyme, without the need to control the reaction conditions strictly. Thirdly, the designed amplification probes group could be used for the analysis of other pathogenic bacteria, virus, tumor markers, biomarkers, etc. For the detection of S. aureus , the limit of detection (LOD) of the method was 2 pM for standard DNA, with the linear range from 20 pM to 100 nM. Last but not least, the LOD of the S. aureus asymmetric PCR products was 5 pM, with the linear range from 10 pM to 50 nM. The sensitivity was 1–2 orders in magnitude higher than that of the common detection assays. [ABSTRACT FROM AUTHOR]

In conventional modeling of a cable-pulley system, the cable must be finely meshed with Lagrangian elements for valid contact detections with pulleys, leading to extremely low efficiency. The sliding joint method based on the arbitrary-Lagrangian-Eulerian (ALE) formulation still lacks an efficient cable element, and in particular, modeling of friction between a sliding joint and the cable has not been studied. This paper presents efficient multi-body modeling of a cable-pulley system with friction. A variablelength cable element with a node movable along the cable, which is described with ALE, is developed to mesh the cable. A transitional cable element is then proposed to model the contact part of the cable by fixing its two nodes to the two corresponding locations of the pulley. Friction of the cable-pulley is derived as a simple law of tension decay and embedded in the multi-body system modeling. It is simplified as a generalized friction force acting only on the arc-length coordinate. This approach can use a rough mesh on the cable, and is free of contact detections, thus significantly saving computation time. Several examples are presented to validate the proposed method, and show its effectiveness in real engineering applications. [ABSTRACT FROM AUTHOR]

Shift photovoltaic current (SPC) in polar non-centrosymmetric materials has recently emerged as a promising candidate for the next generation photovoltaic devices in which Shockley-Queisser limits are fully overcome. Here, we apply first-principles calculations to predict colossal SPC in the slide bilayers of 2D h -BN and β-GeS vdW homostructures. The large SPC in slide bilayers h -BN and β-GeS reaches 49.3 μAV−2 and 130 μ μAV−2, respectively, in the ultra-violet (UV) region. Increasing the number of layers is further implemented to tune the band structure of the two homostructures. Consequently, giant SPC peaks about 3 times larger than those of the bilayers are predicted at photon energies of 7.40 eV and 5.95 eV in the 5-layers of h -BN and β-GeS, respectively. The two homostructures are thus promising building blocks for next-generation photovoltaic devices. These findings also suggest layering as a possible convenient approach to enhancing and also tuning the SPC output in thin layered materials. Bi- and few-layered homostructures of h -BN and β-GeS are possible excellent candidate materials for generation of strong BPVE, essential in design and performance improvement of efficient solar energy conversion and photodetection. [Display omitted] • The AB stacked bilayers of h -BN, and β-GeS homostructures host large tunable shift photocurrent in the ultraviolet range. • Increasing of the number of layers of h -BN, and β-GeS homostructures results in magnitude enhancement as well as direct change of shift photocurrent. • Thiswork opens a pathway for experimental verification, and exploring of efficient photovoltaic devices via BPVE based on current homostructures and similar materials. [ABSTRACT FROM AUTHOR]

Highlights: [•] We find that there are three dominant growth stages for C clusters on BN: monatomic quantum wires, monatomic quantum rings and hexagonal honeycomb structures. [•] Monatomic C quantum wires are found to be stable during the initial growth stage when the number of atoms is less than 10. The critical number of atoms for quantum rings is 22. [•] Hexagonal honeycomb structures dominate the third and final growth stage which results in graphene layer. No critical size is found for hexagonal honeycomb nanoclusters, as the stability of hexagonal honeycomb nanoclusters increases with cluster size. [•] The presence of C5 ring units has a negative impact on a cluster's stability and also acts as the source of a magnetic moment due to the unpaired 2p electron. [•] 3D-like C cluster structures are not stable on a BN substrate. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we report a novel cellulase [β-1,4-endoglucanase (EGase), EC 3.2.1.4] cDNA (Bh-EGase II) belonging to the glycoside hydrolase family (GHF) 45 from the beetle Batocera horsfieldi. The Bh-EGase II gene spans 720bp and consists of a single exon coding for 239 amino acid residues. Bh-EGase II showed 93.72% protein sequence identity to Ag-EGase II from the beetle Apriona germari. The GHF 45 catalytic site is conserved in Bh-EGase II. Bh-EGase II has three putative N-glycosylation sites at 56–58 (N–K–S), 99–101 (N–S–T), and 237–239 (N–Y–S), respectively. The cDNA encoding Bh-EGase II was expressed in baculovirus-infected insect BmN cells and Bombyx mori larvae. Recombinant Bh-EGase II from BmN cells and larval hemolymph had an enzymatic activity of approximately 928U/mg. The enzymatic catalysis of recombinant Bh-EGase II showed the highest activity at 50°C and pH6.0. [Copyright &y& Elsevier]

The presence and precise structures of the glycans attached at the Fc domain of monoclonal antibodies play an important role in determining antibodies' effector functions such as antibody-dependent cell cytotoxicity (ADCC), complement activation, and anti-inflammatory activity. This paper describes a novel approach for glycoengineering of human IgG1 -Fc that combines high-yield expression of human IgG1-Fc in yeast and subsequent in vitro enzymatic glycosylation, using the endoglycosidase-catalyzed transglycosylation as the key reaction. Human IgG1-Fc was first overproduced in Pichia pastoris. Then the heterogeneous yeast glycans were removed by Endo-H treatment to give the GIcNAc-containing IgG1- Fc as a homodimer. Finally, selected homogeneous glycans were attached to the G1cNAc-primer in the IgG1 -Fc through an endoglycosidase-catalyzed transglycosylation, using sugar oxazolines as the donor substrates. It was found that the enzymatic transglycosylation was efficient with native G1cNAc-containing IgG1-Fc homodimer without the need to denature the protein, and the reaction could proceed to completion to give homogeneous glycoforms of IgG1-Fc when an excess of oligosaccharide oxazolines was used as the donor substrates. The binding of the synthetic IgG1 -Fc glycoforms to the FcγIIa receptor was also investigated. This novel glycoengineering approach should be useful for providing various homogeneous, natural or synthetic glycoforms of IgG1-Fc for structure-function relationship studies, and for future clinical applications. [ABSTRACT FROM AUTHOR]

By first-principles calculations, we investigate the geometric stability, electronic and optical properties of the type-II PN-WSe2 and type-I PAs-WSe2 van der Waals heterostructures(vdWH). They are p-type semiconductors with indirect band gaps of 1.09 eV and 1.08 eV based on PBE functional respectively. By applying the external gate field, the PAs-WSe2 heterostructure would transform to the type-II band alignment from the type-I. With the increasing of magnitude of the electric field, two heterostructures turn into the n-type semiconductors and eventually into metal. Especially, PN/PAs-WSe2 vdWH are both high refractive index materials at low frequencies and show negative refractive index at high frequencies. Because of the steady absorption in ultraviolet region, the PAs-WSe2 heterostructure is a highly sensitive UV detector material with wide spectrum. The type-II PN-WSe2 heterostructure possesses giant and broadband absorption in the near-infrared and visible regions, and its solar power conversion efficiency of 13.8% is higher than the reported GaTe–InSe (9.1%), MoS2/p-Si (5.23%) and organic solar cells (11.7%). It does project PN-WSe2 heterostructure a potential for application in excitons-based solar cells. [ABSTRACT FROM AUTHOR]

We report properties of parametric electron pumping in the presence of a superconducting lead. Due to a constructive interference between the direct reflection and the multiple Andreev reflection, the pumped current is greatly enhanced. For both quantum point contacts and double barrier structures at resonance, we obtain exact solutions in the weak pumping regime showing that I[sup NS][sub p] = 4I[sup N][sub p], which should be compared with the result of conductance G[sub NS] = 2 G[sub N]. Numerical results are also provided for the strong pumping regime showing interesting Andreev assisted pumping behavior. [ABSTRACT FROM AUTHOR]

Sialic acid-binding Ig-like lectin 8 (Siglec-8) is expressed on the surface of human eosinophils, mast cells, and basophils—cells that participate in allergic and other diseases. Ligation of Siglec-8 by specific glycan ligands or antibodies triggers eosinophil death and inhibits mast cell degranulation; consequences that could be leveraged as treatment. However, Siglec-8 is not expressed in murine and most other species, thus limiting preclinical studies in vivo. Based on a ROSA26 knock-in vector, a construct was generated that contains the CAG promoter, a LoxP-floxed-Neo-STOP fragment, and full-length Siglec-8 cDNA. Through homologous recombination, this Siglec-8 construct was targeted into the mouse genome of C57BL/6 embryonic stem (ES) cells, and chimeric mice carrying the ROSA26-Siglec-8 gene were generated. After cross-breeding to mast cell-selective Cre-recombinase transgenic lines (CPA3-Cre, and Mcpt5-Cre), the expression of Siglec-8 in different cell types was determined by RT-PCR and flow cytometry. Peritoneal mast cells (dual FcεRI+ and c-Kit+) showed the strongest levels of surface Siglec-8 expression by multicolor flow cytometry compared to expression levels on tissue-derived mast cells. Siglec-8 was seen on a small percentage of peritoneal basophils, but not other leukocytes from CPA3-Siglec-8 mice. Siglec-8 mRNA and surface protein were also detected on bone marrow-derived mast cells. Transgenic expression of Siglec-8 in mice did not affect endogenous numbers of mast cells when quantified from multiple tissues. Thus, we generated two novel mouse strains, in which human Siglec-8 is selectively expressed on mast cells. These mice may enable the study of Siglec-8 biology in mast cells and its therapeutic targeting in vivo. [ABSTRACT FROM AUTHOR]

Orbital-free density functional theory (OFDFT) replaces the wavefunction in the kinetic energy by an explicit energy functional and thereby speeds up significantly the calculation of ground state properties of the solid state systems. So far, the application of OFDFT has been centered on closed systems and less attention is paid on the transport properties in open systems. In this paper, we use OFDFT and combine it with non-equilibrium Green's function to simulate equilibrium electronic transport properties in silicon nanostructures from first principles. In particular, we study ac transport properties of a silicon atomic junction consisting of a silicon atomic chain and two monoatomic leads. We have calculated the dynamic conductance of this atomic junction as a function of ac frequency with one to four silicon atoms in the central scattering region. Although the system is transmissive with dc conductance around 4 to 5 e2/h, capacitive-like behavior was found in the finite frequency regime. Our analysis shows that, up to 0.1 THz, this behavior can be characterized by a classic RC circuit consisting of two resistors and a capacitor. One resistor gives rise to dc resistance and the other one accounts for the charge relaxation resistance with magnitude around 0.2 h/e2 when the silicon chain contains two atoms. It was found that the capacitance is around 5 aF for the same system. [ABSTRACT FROM AUTHOR]

In this study, we examined the mechanism of Flavone of Hippophae (H-flavone) in regulating macrophage foaming and atherosclerosis (AS) plaque formation. H-flavone treatment increased the secretion of C1q/tumor necrosis factor-related proteins 6 (CTRP6) in Ox-LDL-treated mouse peripheral blood macrophage cells (PBMC) and significantly reduced the percentage of cholesteryl ester (CE) in PBMC. Additionally, H-flavone suppressed Ox-LDL-induced cell foaming and the production of inflammatory cytokines through upregulating CTPR6 expression. Next, we further validated the inhibitory effect of H-flavone on plaque formation and inflammation in a mouse AS model. A substantial reduction in the secretion of inflammatory cytokines was observed in apoE-/- mice by H-flavone. Immunohistochemistry and Oil Red O staining results showed that H-flavone suppressed macrophage infiltration and the development of AS plaque. These effects were more pronounced in early administration. Our results suggest that H-flavone effectively inhibits macrophage foaming, inflammation and vascular plaque formation by upregulating CTRP6 and may be used to reduce AS risk. H-flavone suppresses macrophage foaming by upregulating CTPR6 in vitro. H-flavone inhibits macrophage infiltration and AS plaque development in vivo. [ABSTRACT FROM AUTHOR]

Wide bandgap β-Ga2O3 is an ideal candidate material with broad application prospects for power electronic components in the future. Aiming at the application requirements of β-Ga2O3 in space photoelectric devices, this work studies the influence of 40 MeV Si ion irradiation on the microstructure and optical properties of β-Ga2O3 epi-wafers. Raman spectroscopy analysis confirms that Si ion irradiation destroys the symmetric stretching mode of tetrahedral–octahedral chains in β-Ga2O3 epi-wafers, and the obtained experimental evidence of irradiation leads to the enhanced defect density of VO and VGa–VO from x-ray photoelectron spectroscopy. Combined with first-principles calculations, we conclude that most configurations of VO and VGa–VO are likely non-radiative, leading to quenching of experimental photoluminescence intensity. Unraveling optical degradation mechanism and predicting the optical application of β-Ga2O3 devices in the space environment by combining ground irradiation experiments with first-principles calculations still be one of the focuses of research in the future. [ABSTRACT FROM AUTHOR]

The heat transfer and flow of nanofluids in microchannel heat sink is usually numerically investigated by the single-phase model. The thermal conductivity and viscosity of nanofluids are calculated in the whole computational region because the single-phase model, assumes the nanofluids is static and nanoparticles concentration is uniform. However for the actual forced flow process, the concentration distribution of the nanofluids is not uniform. So the thermal properties of the nanofluids vary within different computational regions. With the increase of the velocity of the nanofluids, the deviation between the prediction of single-phase model and experimental results increases. In this paper, a new simulation method is proposed to consider the inhomogeneous and dynamic thermophysical properties of the nanofluids by obtaining the nonuniformly distributed nanoparticle concentration in each numerical cell. At the same time, it takes into account the following factors: the interactions between the nanoparticles, the solid wall and the base fluid, the axial conduction, the slip boundary conditions and fluid-solid coupling. The results show that the proposed numerical simulation method further improve the simulation accuracy for the forced flow and heat transfer process of nanofluids in the microchannel in a wider range. The effects of the nanoparticles concentration, Reynolds number and axial heat transfer on the thermophysical properties of the nanofluilds, the flow and heat transfer characteristics of a rectangular microchannels with hydraulic dimensions of 341 μm were analyzed using the proposed simulation model. The main results are as follows: the nanoparticles are enriched at the near wall for the fully developed region; the nonuniformity of the nanofluilds thermal conductivity coefficient distribution at the channel cross section increases with the increase of the mass flow rate and the inlet centration; under the same Reynolds number, the higher the nanofluids concentration the better the heat transfer characteristics, but there is no linear relationship between the enhancement amplitude and concentration; the heat transfer coefficient of nanofluid with 1% and 2% alumina nanoparticles concentration is about 5.86% and 8.49% higher than that of deionized water, respectively; the axial conduction effect cannot be ignored for the microchannel, which significantly affects the inlet and outlet region of the microchannel especially when the Reynolds number is low. The nanofluilds temperature in the microchannel increases with the curve and does not match the conventional linear growth hypothesis. [ABSTRACT FROM AUTHOR]

This paper identifies the location of E C -0.9 eV trap caused by irradiation in AlGaN/GaN high electron mobility transistors (AlGaN/GaN-HEMTs). Helium ions at 40 keV and 400 keV were selected as the irradiation source. The 40 keV He ions only causes damage in the passivation and AlGaN layer, while the 400 keV He ions will cause damage mainly in GaN layer. The test results show that the threshold voltage of the device positive shift after 400 keV He ion irradiation. The carrier mobility and the Schottky barrier also show decreases. Deep level transient spectrum (DLTS) results show a defect with E C -0.9 eV in GaN layer after irradiation. While, the displacement damage in the passivation and AlGaN layer cause negative shift of the threshold voltage and the decrease of the carrier mobility. Combined with the DLTS and TCAD simulation, the location of defects with E C -0.9 eV caused by displacement damage is in the GaN layer. [ABSTRACT FROM AUTHOR]

Recent progress on qubit manipulation allows application of periodic driving signals on qubits. In this study, a harmonic driving field is added to a Rabi dimer to engineer photon and qubit dynamics in a circuit quantum electrodynamics device. To model environmental effects, qubits in the Rabi dimer are coupled to a phonon bath with a sub-Ohmic spectral density. A nonperturbative treatment, the Dirac-Frenkel time-dependent variational principle together with the multiple Davydov D2 ansatz, is employed to explore the dynamical behavior of the tunable Rabi dimer. In the absence of the phonon bath, the amplitude damping of the photon number oscillation is greatly suppressed by the driving field, and photons can be created, thanks to the resonance between the periodic driving field and the photon frequency. In the presence of the phonon bath, one can still change the photon numbers in two resonators and indirectly alter the photon imbalance in the Rabi dimer by directly varying the driving signal in one qubit. It is shown that qubit states can be manipulated directly by the harmonic driving. The environment is found to strengthen the interqubit asymmetry induced by the external driving, opening up a new venue to engineer the qubit states. [ABSTRACT FROM AUTHOR]

Electron traps in AlGaN/GaN high electron mobility transistors were studied by combining theoretical and experimental methods. Energy levels about EC-0.9 eV due to irradiation are identified by deep-level transient spectroscopy (DLTS). Two electron traps, H1 (EC-0.63 eV) and H2 (EC-0.9 eV), were observed in the DLTS spectra. H1 was produced in device or material manufacturing, and H2 was caused by displacement damage. First, we reported that the signal peak of H2 can contribute from three defects labeled H2-1, H2-2, and H2-3 with energies EC-0.77 eV, EC-0.9 eV, and EC-0.98 eV, respectively. According to defect migration temperature and first principles calculation results, it is found that different configurations of di-nitrogen vacancy structures are the source of EC-0.77 eV and EC-0.9 eV signals. The defect of EC-0.98 eV is more stable at high temperatures, which may be related to gallium vacancy. [ABSTRACT FROM AUTHOR]

This article investigates the displacement damage on AlGaN/GaN high-electron-mobility transistors (HEMTs) using the 30-MeV fluorine ions. The electrical degradation and the defects in HEMTs were examined before and after irradiation. Three defect states are detected in a deep-level transient analysis system (DLTS), including a broad surface state peak ($N_{1}$) and two bulk defect peaks ($H_{1}$ and $H_{2}$). The energy levels of these two defects are $E_{\mathrm {C}} 0.63$ eV ($H_{2}$) and $E_{\mathrm {C}} 0.91$ eV ($H_{1}$), respectively. There is a linear relationship between the concentration of $H_{1}$ and the fluorine ion fluence. The radiation damage and electrical performance degradation of AlGaN/GaN HEMTs are simulated by combining with simulation software of different methods. The calculated results are in agreement with the experimental data. The performance degradation caused by heavy ion of the device is mainly caused by the $H_{1}$ defect. The effect of defects with shallow energy level is shielded by the Fermi-level pinning in deeper energy level. Moreover, the defect distribution of GaN in AlGaN/GaN heterojunction plays a major role. It is found that the method of combining experimental data with multiscale simulation is an effective way to predict the radiation damage of devices. [ABSTRACT FROM AUTHOR]

In order to achieve the transistor-less circuit, which has remarkable potentials for high speed, high-density integration, and low power consumption applications, a 1-selector−1-resistor (1S − 1R) structure is utilized in this work to replace the prevalent 1-transistor−1-resistor (1T − 1R) array of memristor synaptic architectures. The 1S − 1R structure consists of a four-terminal memristor acting as a selector and a two-terminal memristor storing information in the form of device resistances. The high resistance state (HRS) and the low resistance state (LRS) of two-terminal memristor are used in conjunction to represent binary weight in binary neural networks (BNN), and multiply-accumulate operation of convolution can be replaced by the current accumulation of the 1S − 1R circuit. With the purpose of mapping binary weights into the 1S − 1R array to implement the forward propagation at the circuit simulation level, a LeNet model has been modified herein where two full-precision convolution layers are replaced by two binary convolutional layers. Compared with the full-precision LeNet model, the storage resource consumption of the binarized network is reduced by 44.28%, while the accuracy can reach 98% in 10 epochs, which is very close to the full-precision network. The 1S − 1R array is used subsequently to store the binary weight of a convolution layer in the trained LeNet and 100 pictures with numbers 0 to 9 in MNIST are randomly selected for testing. As expected, the result obtained through circuit simulation is consistent with the convolution operation in the process of forward propagation. [Display omitted] • Developed a novel 1-selector-1-resistor architecture. • Developed 1-bit synaptic cell to realize XNOR operation. • Analog current accumulation instead of digital methods. • Performance almost similarly excellent in binary network compared with full-precision network. [ABSTRACT FROM AUTHOR]

The performance of lithium–sulfur (Li–S) battery is strongly dependent on the sulfur electrodes materials. Due to the chemical interaction between electrodes and intermediates produced in charging and discharging process, the Janus‐polar two dimensional (2D) electrode materials can enhance the electrochemical performance of Li–S battery by overcoming shuttle effect and increasing diffusion rates. Here, it is explored the structural, electronic, and dynamic characteristics of Li ion, S8 cluster, and lithium polysulfides adsorbed over Janus Phosphorus Nitride monolayer with blue phosphorene phase (b‐PN) by using first‐principles calculations. The reported findings highlight potential of the b‐PN monolayer as a good host material, given that the large absorption energies of different clusters vary from −0.47 to −3.78 eV, which can suppress shuttle effect effectively. These strong adsorptions are origin from the chemical interaction between nitrogen atoms of the b‐PN and Li atoms in lithium polysulfides in present work. Particularly, it is predicted that b‐PN monolayer has extremely small diffusion barriers for Li ion and Li2S8 clusters of 0.10 and 0.03 eV, which leading to a higher battery charge and discharge rate than reported graphene and MoS2. It is hoped that this efficient strategy for promising host materials of sulfur‐electrode guides the development of next‐generation lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

We present a theoretical analysis of thermoelectric transport in the nonlinear regime. The thermopower and thermoconductance at finite temperature gradient are calculated numerically for a double barrier structure using Landauer Büttiker like formula. The thermopower is found to oscillate with the chemical potential. Thermopower can either be negative or positive which is well correlated with the behavior of the electric conductance. The thermal conductance is positive definite showing that the heat energy is always transferred from hot end to cold end. As the chemical potential is varied, nonlinear thermal conductance exists plateau-like features. [ABSTRACT FROM AUTHOR]

The electro-optical properties of Indium Selenide/Black Arsenic Phosphorus (InSe/α-AsP) van der Waals heterojunction have been systematically investigated by using first-principles calculations. The presented two-dimensional (2D) heterojunction possesses a narrow direct bandgap (1.07 eV), with a high absorption coefficient in the infrared region and a cutoff wavelength of ~2 μm. Type-II band alignment is predicted which would lead to an efficient separation of electrons and holes. Charge carrier mobilities are calculated reaching up to 103 cm2V−1s−1 at room-temperature, which promises high-performance electron transport behavior. Lattice strain is revealed to tune the band structure but without changing the type-II band alignment of the InSe/α-AsP van der Waals heterojunction. These results suggest that InSe/α-AsP van der Waals heterojunction is a promising candidate for infrared photodetection devices. • We design a stable InSe/α-AsP vdW heterostructure with narrow direct band gap. • The InSe/α-AsP vdWH show a significant amount of optical absorption in the infrared region. • The InSe/α-AsP vdWH have higher efficiency of electron–hole separation and transfer because of its critical type-II band alignment. [ABSTRACT FROM AUTHOR]

The Janus MoSSe has attracted much attention since its successful synthetization in experiment. Due to the inversion symmetry breaking in vertical direction, it has an inner-built electric field and has potential applications in many fields such as optoelectronic devices and photocatalysis. Although its two-dimensional form has been widely investigated, the properties of Janus MoSSe nanotube has not been systematically investigated. In this work, we calculated the formation energy and projected band structure of Janus MoSSe nanotube with first principle calculation. Different morphologies such as singe wall nanotube and double wall nanotube are considered. Other factors such as the position of S atom and Se atom and the radius of nanotube are also considered. As last, we proved that the band structure is robust under rotation operation and translation operation. This work will shed some lights on the application of Janus MoSSe nanotube in optoelectronic field. [ABSTRACT FROM AUTHOR]

Src homology 2 domain–containing inositol 5-phosphatase 1 (SHIP-1) regulates the intracellular levels of phosphotidylinositol-3, 4, 5-trisphosphate, a phosphoinositide 3–kinase (PI3K) product. Emerging evidence suggests that the PI3K pathway is involved in allergic inflammation in the lung. Germline or induced whole-body deletion of SHIP-1 in mice led to spontaneous type 2-dominated pulmonary inflammation, demonstrating that SHIP-1 is essential for lung homeostasis. However, the mechanisms by which SHIP-1 regulates lung inflammation and the responsible cell types are still unclear. Deletion of SHIP-1 selectively in B cells, T cells, dendritic cells (DC) or macrophages did not lead to spontaneous allergic inflammation in mice, suggesting that innate immune cells, particularly group 2 innate lymphoid cells (ILC2 cells) may play an important role in this process. We tested this idea using mice with deletion of SHIP-1 in the hematopoietic cell lineage and examined the changes in ILC2 cells. Conditional deletion of SHIP-1 in hematopoietic cells in Tek-Cre/SHIP-1 mice resulted in spontaneous pulmonary inflammation with features of type 2 immune responses and airway remodeling like those seen in mice with global deletion of SHIP-1. Furthermore, when compared to wild-type control mice, Tek-Cre/SHIP-1 mice displayed a significant increase in the number of IL-5/IL-13 producing ILC2 cells in the lung at baseline and after stimulation by allergen Papain. These findings provide some hints that PI3K signaling may play a role in ILC2 cell development at baseline and in response to allergen stimulation. SHIP-1 is required for maintaining lung homeostasis potentially by restraining ILC2 cells and type 2 inflammation. [ABSTRACT FROM AUTHOR]

van der Waals heterostructures (vdWHs) based on two-dimensional (2D) materials have been extensively recognized as promising candidates for fabricating multi-functional novel devices. In this work, we investigated the structural and electronic properties of the InS–arsenene vdWH in some detail by using the first principles calculation method to explore its potential application in nanoelectronics. Numerical results show that the InS–arsenene vdWH possesses a stable structure, excellent flexibility, high carrier mobility and direct band gap semiconducting behavior. In particular, its electronic properties can be regulated effectively by vertical strain, in-plane strain and an external electric field. Vertical strain can tune the band gap of the semiconducting vdWH in a wide range with stable type-II band alignment. However, in-plane strain and an external electric field can even realize phase transitions from semiconducting to metallic behaviors, which implies great application potential of the InS–arsenene vdWH in multi-purpose nanoelectronic devices, optoelectronic devices and tunnel field-effect transistors (TFETs). This theoretical work would provide valuable guidance for fabricating the InS–arsenene vdWH and extending the application of InS and arsenene monolayers. [ABSTRACT FROM AUTHOR]

The structural and electronic properties of synergistically modified blue phosphorene (BP) is investigated. The inversion and threefold rotational symmetries of BP are broken. The codoping of group IV and VI impurities can turn monolayer BP into direct bandgap semiconductors. The underlying physical mechanism is that group IV and VI impurities tailor the valence band maximum and conduction band minimum, respectively, and move them to Γ. All the bandgaps of monolayer, nanoribbons, and quantum dots of BP can be modulated in a wide range, and the strong bandgap bowing is found. In addition, the Coulomb interactions between the screened impurities are revealed. Lower formation energies indicate the fabricating practicability of synergeticly modified BP. Spin–orbit coupling (SOC) can also be tuned by the introduction of impurities. The band structure of blue phosphorene (BP) is engineered through synergetic codoping with group IV and VI impurities. The indirect to direct bandgap transition is found. The bandgap of BP can be modulated in a wide range, and strong bandgap bowing is found. Lower formation energies indicate that practical fabrication is a possibility. [ABSTRACT FROM AUTHOR]

Nighttime light data have been proven to perform well for economic measurements and built-up area extractions. However, the new generation of monthly NPP/VIIRS data series products, which collected from the Visible Infrared Imaging Radiometer Suite (VIIRS) sensor on the Suomi National Polar-orbiting Partnership (NPP) Satellite contains background values, which relatively restrict the potential application of nighttime images. Therefore, the image layer difference index (LDI) was constructed to obtain high-intensity pixels that have radiance mainly caused by urban light glow. In addition, an empirical threshold was used to extract low-intensity pixels. Thirty-eight counties in Chongqing Province in China were used as an example for this experimental research. To verify the accuracy of the proposed method, a linear regression model, which was based on the quantitative statistics of the pixels, exhibited the coefficient of determination R2 values of 0.980 and 0.947. Considering the interrelation between the light intensity and economic level, statistical data of the county-level economy was also used for further confirmation; the R2 values of the linear regression between the computed indexes were 0.924 and 0.909. [ABSTRACT FROM AUTHOR]

Human siglecs are a family of 14 sialic acid-binding proteins, most of which are expressed on subsets of immune cells where they regulate immune responses. Siglec-8 is expressed selectively on human allergic inflammatory cells—primarily eosinophils and mast cells—where engagement causes eosinophil apoptosis and inhibits mast cell mediator release. Evidence supports a model in which human eosinophils and mast cells bind to Siglec-8 sialoglycan ligands on inflammatory target tissues to resolve allergic inflammation and limit tissue damage. To identify Siglec-8-binding sialoglycans from human airways, proteins extracted from postmortem human trachea were resolved by size-exclusion chromatography and composite agarose–acrylamide gel electrophoresis, blotted and probed by Siglec-8-Fc blot overlay. Three size classes of Siglec-8 ligands were identified: 250 kDa, 600 kDa and 1 MDa, each of which was purified by affinity chromatography using a recombinant pentameric form of Siglec-8. Proteomic mass spectrometry identified all size classes as the proteoglycan aggrecan, a finding validated by immunoblotting. Glycan array studies demonstrated Siglec-8 binding to synthetic glycans with a terminal Neu5Acα2-3(6-sulfo)-Gal determinant, a quantitatively minor terminus on keratan sulfate (KS) chains of aggrecan. Treating human tracheal extracts with sialidase or keratanase eliminated Siglec-8 binding, indicating sialylated KS chains as Siglec-8-binding determinants. Treating human tracheal histological sections with keratanase also completely eliminated the binding of Siglec-8-Fc. Finally, Siglec-8 ligand purified from human trachea extracts induced increased apoptosis of freshly isolated human eosinophils in vitro. We conclude that sialylated KS proteoglycans are endogenous human airway ligands that bind Siglec-8 and may regulate allergic inflammation. [ABSTRACT FROM AUTHOR]

An intelligent land vehicle utilizes onboard sensors to acquire observed states at a disorderly intersection. However, partial observation of the environment occurs due to sensor noise. This causes decision failure easily. A collision relationship-based driving behavior decision-making method via deep recurrent Q network (CR-DRQN) is proposed for intelligent land vehicles. First, the collision relationship between the intelligent land vehicle and surrounding vehicles is designed as the input. The collision relationship is extracted from the observed states with the sensor noise. This avoids a CR-DRQN dimension explosion and speeds up the network training. Then, DRQN is utilized to attenuate the impact of the input noise and achieve driving behavior decision-making. Finally, some comparative experiments are conducted to verify the effectiveness of the proposed method. CR-DRQN maintains a high decision success rate at a disorderly intersection with partially observable states. In addition, the proposed method is outstanding in the aspects of safety, the ability of collision risk prediction, and comfort. [ABSTRACT FROM AUTHOR]

• Dual cobalt active species encapsulated in carbon matrix have been obtained. • Rational construction of dual cobalt active species has been visualized. • Spatially separated Co and CoO x were integrated together in carbon matrix. • Remarkable H 2 generation rate is achieved over dual cobalt active species. • Mechanism of charge transfer and separation has been discussed. Dual cocatalyst which integrates the merits of metal and metal oxide has been endowed with competitive advantages over noble metals for achieving efficient H 2 evolution. In this case, developing spatially separated dual cocatalyst in carbon substrate with more efficient charge extraction and separation would be beneficial for further enhancing the photocatalytic activity. Herein, we utilized ultrathin two-dimensional (2D) Co-based MOF (Co-MOF) nanosheets as specific precursors for preparing carbon matrix encapsulated dual cobalt active species (Co and CoO x) on the surface of CdS for high-efficient photocatalytic H 2 evolution under visible-light irradiation. The fundamental roles of 2D-MOF derived carbon matrix towards rational construction of dual cobalt active species have been visualized by combining a series of in-situ and ex-situ temperature-dependent analytic strategies. The carbon matrix as well as co-existed dual cobalt active species bring great improvement on charge carrier transportation and photogenerated electron-hole separation for enhanced photocatalytic activities, and an approximate 12.5-fold enhancement of H 2 generation performance from 0.161 mmol h−1 of CdS to 1.997 mmol h−1 of the newly formed CdS-Co-CoO x @C with the apparent quantum efficiency of 43.7 % at 420 nm has been achieved. This work might provide the basic understanding and new opportunities in manipulating MOF structure through pyrolysis to fabricate high efficient cocatalysts for versatile photocatalytic reactions. [ABSTRACT FROM AUTHOR]

Very recently, two new two-dimensional (2D) layered semi-conducting materials MoSi 2 N 4 and WSi 2 N 4 were successfully synthesized in experiments, and a large family of these two 2D materials, namely MA 2 Z 4 , was also predicted theoretically (Science, 369, 670 (2020)). Motivated by this exciting family, in this work, we systematically investigate the mechanical, electronic and optical properties of monolayer and bilayer MoSi 2 P 4 and MoSi 2 As 4 by using the first-principles calculation method. Numerical results indicate that both monolayer and bilayer MoSi 2 Z 4 (Z = P, As) present good structural stability, isotropic mechanical parameters, moderate bandgap, favorable carrier mobilities, remarkable optical absorption, superior photon responsivity and external quantum efficiency. Especially, due to the wave-functions of band edges dominated by d orbital of the middle-layer Mo atoms are screened effectively, the bandgap and optical absorption hardly depend on the number of layers, providing an added convenience in the experimental fabrication of few-layer MoSi 2 Z 4 -based electronic and optoelectronic devices. We also build a monolayer MoSi 2 Z 4 -based 2D optoelectronic device, and quantitatively evaluate the photocurrent as a function of energy and polarization angle of the incident light. Our investigation verifies the excellent performance of a few-layer MoSi 2 Z 4 and expands their potential application in nanoscale electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Citrus sinensis (L.) Osbeck is an important economic product in South China, but the presence of quarantine pests in this product proposes the potential threat to international trade security. To find a proper phytosanitary cold treatment for Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), commonly called oriental fruit fly, one of the most serious quarantine insects in navel orange, eggs in petri dish and larvae in navel orange fruits were exposed to a 1.7 °C cold chamber for 0–11 days to compare the tolerance to cold treatment. The 2nd instar larva (4 days) is the most tolerant stage, and the estimated time for 99.9968% mortality at the 95% confidence level is 11.3 (9.5, 14.6) days. Then 15 days was selected as the target time for the confirmatory tests, resulting in no survivors from 37,792 treated larvae with the efficacy of 99.9921% mortality at the 95% confidence level. The quality assessments were conducted to compare the effect on the navel orange fruit between cold treatment and the conventional cold storage. Results indicated that the cold treatment did not negatively affect the fruit quality. Therefore, this cold treatment showed potential as a commercial quarantine treatment for navel orange in international trade. [ABSTRACT FROM AUTHOR]

A Rabi dimer is used to model a recently reported circuit quantum electrodynamics system composed of two coupled transmission‐line resonators with each being coupled to one qubit. In this study, a phonon bath is adopted to mimic the multimode micromechanical resonators and is coupled to the qubits in the Rabi dimer. The dynamical behavior of the composite system is studied by the Dirac–Frenkel time‐dependent variational principle combined with the multiple Davydov D2 ansätze. Initially, all the photons are pumped into the left resonator, and the two qubits are in the down state coupled with the phonon vacuum. In the strong qubit–photon coupling regime, the photon dynamics can be engineered by tuning the qubit–bath coupling strength α and photon delocalization is achieved by increasing α. In the absence of dissipation, photons are localized in the initial resonator. Nevertheless, with moderate qubit–bath coupling, photons are delocalized with quasiequilibration of the photon population in two resonators at long times. In this case, high‐frequency bath modes are activated by interacting with depolarized qubits. For strong dissipation, photon delocalization is achieved via frequent photon‐hopping within two resonators and the qubits are suppressed in their initial down state. The Dirac–Frenkel time‐dependent variational principle combined with the multiple Davydov D2 ansätze are adopted to investigate the dynamical behavior of a Rabi dimer with qubits coupled to a phonon bath. In the strong qubit–photon coupling regime, it is found that the photon dynamics can be engineered by tuning the qubit–bath coupling strength. [ABSTRACT FROM AUTHOR]

In article number 1800351, Yang Zhao and co‐workers adopt the Dirac–Frenkel time‐dependent variational principle combined with multiple Davydov D2 ansätze to investigate the dynamical behavior of Rabi dimers with qubits coupled to a phonon bath. Photons can hop between two transmission‐line resonators with a tunneling rate J. In each resonator, a qubit interacts with the photon mode with a coupling strength g. Two qubits are also coupled to a common phonon bath with a strength d, which can be used to engineer photon delocalization. [ABSTRACT FROM AUTHOR]