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Abstract The emergence of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) variants has altered the trajectory of the COVID‐19 pandemic and raised some uncertainty on the long‐term efficiency of vaccine strategy. The development of new therapeutics against a wide range of SARS‐CoV‐2 variants is imperative. We, here, have designed an inhalable siRNA, C6G25S, which covers 99.8% of current SARS‐CoV‐2 variants and is capable of inhibiting dominant strains, including Alpha, Delta, Gamma, and Epsilon, at picomolar ranges of IC50 in vitro. Moreover, C6G25S could completely inhibit the production of infectious virions in lungs by prophylactic treatment, and decrease 96.2% of virions by cotreatment in K18‐hACE2‐transgenic mice, accompanied by a significant prevention of virus‐associated extensive pulmonary alveolar damage, vascular thrombi, and immune cell infiltrations. Our data suggest that C6G25S provides an alternative and effective approach to combating the COVID‐19 pandemic.

Objective: To investigate the anti-oxidant and anti-inflammatory effects of ethanol extract of Polygala sibirica L. var megalopha Fr. (EEP) on RAW264.7 mouse macrophages. Methods: RAW264.7 cells were pretreated with 0–200 µg/mL EEP or vehicle for 2 h prior to exposure to 1 µg/mL lipopolysaccharide (LPS) for 24 h. Nitric oxide (NO) and prostaglandin (PGE2) production were determined by Griess reagent and enzyme-linked immunosorbent assay (ELISA), respectively. The mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), interleukin-1beta (IL-1β), and IL-6 were determined using reverse transcription polymerase chain reaction (RT-PCR). Western blot assay was used to determine the protein expressions of iNOS, COX-2, phosphorylation of extracellular regulated protein kinases (ERK1/2), c-Jun N-terminal kinase (JNK), inhibitory subunit of nuclear factor Kappa B alpha (Iκ B-α) and p38. Immunofluorescence was used to observe the nuclear expression of nuclear factor-κ B p65 (NF-κ B p65). Additionally, the anti-oxidant potential of EEP was evaluated by reactive oxygen species (ROS) production and the activities of catalase (CAT) and superoxide dismutase (SOD). The 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH), superoxide anion (O2−) radical and nitrite scavenging activity were also measured. Results: The total polyphenol and flavonoid contents of EEP were 23.50±2.16 mg gallic acid equivalent/100 g and 43.78±3.81 mg rutin equivalent/100 g. With EEP treatment (100 and 150 µg/mL), there was a notable decrease in NO and PGE2 production induced by LPS in RAW264.7 cells by downregulation of iNOS and COX-2 mRNA and protein expressions (P<0.01 or P<0.05). Furthermore, with EEP treatment (150 µg/mL), there was a decrease in the mRNA expression levels of TNF-α, IL-1β and IL-6, as well as in the phosphorylation of ERK, JNK and p38 mitogen-activated protein kinase (MAPK, P<0.01 or P<0.05), by blocking the nuclear translocation of NF-κ B p65 in LPS-stimulated cells. In addition, EEP (100 and 150 µg/mL) led to an increase in the anti-oxidant enzymes activity of SOD and CAT, with a concomitant decrease in ROS production (P<0.01 or P<0.05). EEP also indicated the DPPH, OH, O2− radical and nitrite scavenging activity. Conclusion: EEP inhibited inflammatory responses in activated macrophages through blocking MAPK/NF-κ B pathway and protected against oxidative stress. [ABSTRACT FROM AUTHOR]

Pollution of municipal sewage sludge with heavy metals (HMs) inevitably causes secondary contamination, threatening ecosystems and human health. Dissolved organic matters (DOM) would serve as HMs carriers or ligands, directly influencing the transport and distribution. So it is of essential importance to simultaneously evaluate the release characteristics of HMs and DOM from MSS. In this paper, we investigated leaching characteristics of HMs (Cd, Cr, Cu, Zn, Ni, and Mn) and DOM from raw sewage sludge (RSS) and lime-conditioned sewage sludge (LCSS) under simulated rain with different acidities (pH 6.5 and 2.9) via column leaching experiments. The results showed the release of HMs could be divided into two distinct stages, a rapid decreasing changes in the early stage and a slow and steady change in the later stages with a slight increase in the middle of time. At the early stage, DOM was dominated by protein-like components (tryptophan-like, tyrosine-like). As time passed, protein-like components decreased while humic-like components (fulvic acid and humic acid) increased gradually. Protein-like components showed significant positive correlations with HMs, while humic acid-like components showed strong negative correlations with them. Moreover, the leaching efficiencies of Cd, Zn and Mn at pH 2.9 was about 1.5 times higher than that at 6.5, and the fluorescence intensity of humic-like components at pH 2.9 was higher than that at pH 6.5, suggesting that acid rain accelerated the release of HMs and the humification of DOM. Compared with the RSS, the DOM of LCSS showed noticeable differences, especially an obvious increase of the fulvic acid component. And the leaching efficiencies of Cd, Cr, Cu, Ni, and Mn in LCSS were much lower than that in RSS, indicating lime treatment retarded the release of HMs. Thus, our findings will be a guide to the treatment of HMs contaminants in MSS. [ABSTRACT FROM AUTHOR]

This article explores the connection between two fields, artificial intelligence (AI) and transhumanist posthumanism. In linking them, the author proposes a distinction of "exhaustion/illustration" to extend various discussions of to what extent AI can learn from human intelligence (HI) and vice versa. Ethnomethodology, whose aim is to study how social members make social settings "observable and accountable", may contribute to our understanding of how, if possible, AI makes its accountings and accounting practices "observable and accountable". Through the lens of ethnomethodology, the distinction will be demonstrated as two logics of approaching and understanding the world. In the beginning, the logic of illustration, belonging to the human mind, creates distance between humans and their world to make things understandable, with no regard to how things can be truly represented or not. Later in the history of scientific and technological development, especially in pursuing exactness, steadiness, and predictability, the logic of exhaustion has been gradually developed to eliminate distance through formalizing almost everything, resulting in a situation in which humans and machines imitate each other and become intertwined. In rejecting the grand narratives as post-modernists stated, what comes after has been to be another narrative occupied by the logic of exhaustion. It is this narrative that has penetrated daily life and becomes omnipresent. Humanities can be endangered by internalizing the logic and the relationships between humans and machines cannot be appropriately evaluated if the logic of illustration has been kept overlooked. [ABSTRACT FROM AUTHOR]

Further research into tunneling performance in heterogeneous sand cobble ground demands an accurate numerical model of actual formation. In this paper, the ground model composed of spherical sand and ellipsoidal cobble was constructed to study the rock-breaking performance by using the discrete element method. The shape and physical parameters of sand and cobble were obtained on the basis of field test data. Then, the ground model was constructed to simulate the rock-breaking process of the cutterhead. The results show that the center cutter has a high flat wear percentage. With the decrease in cobble content (CC), the cracks between cutters are not connected effectively, thereby resulting in lower rock-breaking quantity. Finally, the influences of CC on the optimal parameters and crack propagation were analyzed. The results indicate that the rock-breaking performance in the ground with a low CC can be improved by increasing penetration and reducing cutter spacing. [ABSTRACT FROM AUTHOR]

Isoniazid (INH) is a first-line anti-tuberculosis drug used for nearly 70 years. However, the mechanism underlying the side effects of INH has remained elusive. Here, we report that INH and its metabolites induce a post-translational modification (PTM) of histones, lysine isonicotinylation (Kinic), also called 4-picolinylation, in cells and mice. INH promotes the biosynthesis of isonicotinyl-CoA (Inic-CoA), a co-factor of intracellular isonicotinylation. Mass spectrometry reveals 26 Kinic sites in histones in HepG2 cells. Acetyltransferases CREB-binding protein (CBP) and P300 catalyse histone Kinic, while histone deacetylase HDAC3 functions as a deisonicotinylase. Notably, MNase sensitivity assay and RNA-seq analysis show that histone Kinic relaxes chromatin structure and promotes gene transcription. INH-mediated histone Kinic upregulates PIK3R1 gene expression and activates the PI3K/Akt/mTOR signalling pathway in liver cancer cells, linking INH to tumourigenicity in the liver. We demonstrate that Kinic is a histone acylation mark with a pyridine ring, which may have broad biological effects. Therefore, INH-induced isonicotinylation potentially accounts for the side effects in patients taking INH long-term for anti-tuberculosis therapy, and this modification may increase the risk of cancer in humans. [ABSTRACT FROM AUTHOR]

We propose two resource-efficient schemes of direct entanglement measurement of two-qubit Werner states via hybrid interaction system with nitrogen-vacancy (NV) center coupled to micro-cavity. Based on the unconventional encoding mode on auxiliary qubits, our physical unit can realize the hybrid controlled phase gate and controlled-NOT gate between spin and polarization qubits. Utilizing only one copy of initial entangled state, we implement direct concurrence measurement of spin Werner states in NV centers and polarization Werner states of single photons. Both schemes can be transformed into remote ones with the initial entangled states possessed by spatially separated participants. Experimental feasibility analyses indicate that the presented schemes have reliable performance in the current available experimental conditions. [ABSTRACT FROM AUTHOR]

We propose an entanglement purification protocol (EPP) for purifying separate atoms embedded in single-sided optical cavities. The protocol works in an error-detected pattern, the reflection coefficients only appear as a global coefficient, the success or failure cases are heralded by the detection of photons, these merits make the protocol more robust and practical. We discuss the performance of the protocol with current experimental parameters, the results show the success probability of the present EPP is relatively high. The EPP could provide a promising building block for quantum repeaters and quantum networks in the future. [ABSTRACT FROM AUTHOR]

The quantum dense coding in a two atomic system under the non-Markovian environment is investigated in detail. We mainly concentrate on the effects about the environment parameter Γ(or γ) and the purity r of the initial state on the dense coding capacity χ. It is found that the dense coding capacity χ is initially decreased and gradually trends to be a constant nonzero value with evolution of time for different environment parameter Γ(or γ). This constant value is determined the initial state and independent to the environment. In other word, environment noise only affects the process of quantum dense coding, but not affects the final result of dense coding capacity. The purity r of the initial state has a strong influence on the initial value of the χ. Besides, for one value r, dense coding capacity χ is decreased firstly, and then reaches a stable value for a long time, whatever the values of other parameters are, but when the purity r of the initial state increased, the initial value of dense coding capacity increased. [ABSTRACT FROM AUTHOR]

Phosphorus (P) in sewage sludge (SS) has been a concern for decades. Sludge-borne P could exacerbate eutrophication problems once released to aquatic environments. Meanwhile, sludge-borne P would be a valuable alternative source to P minerals. A comprehensive understanding of the occurrence forms and fate of P in SS is required prior to the assessment of environmental implications of sludge-borne P. In the present study, we conducted a nationwide survey on speciation of phosphorus in the SS of China. The average concentration of total phosphorus (TP) in SS was 17.3 ± 5.1 g· kg−1, of which 67.1 ± 8.9% occurred as inorganic forms. Non-apatite inorganic phosphorus constituted the major component (77.6 ± 11.4%) of inorganic phosphorus, with the rest minor portion occurring as apatite phosphorus. Organic P accounted for 26.8 ± 7.9% of TP in SS, showing an average concentration of 4.5 ± 4.2 g· kg−1. Majority of phosphorus in the SS of China occurs as labile forms, suggesting that the environmental implications of SS disposal approaches should be assessed seriously. Sewage sludge produced by China contained 1.1 × 105 t of TP in 2016, and the amount accumulated to 1.0 × 106 t since 2001. Landfill sites are the single most important fate, receiving 8.1 × 105 t of sludge-borne TP since 2001. Land application and building materials are the other two fates of sludge-borne phosphorus. Spatial-temporal variations of phosphorus in the SS of China were also discussed.Graphical abstract [ABSTRACT FROM AUTHOR]

In order to understand the reaction mechanism of Al-killed medium-Mn steel with glazed MgO refractory, some laboratory experiments were conducted at [1873 K (1600 °C)]. The refractory rods were glazed by four different basicity slags, and inserted into liquid steel (Mn:5.5 mass pct) for different times. The results show that MgO refractory can react with medium-Mn steel to generate (Mn, Mg)O solid solution with even (Mn, Mg)O-Al2O3 spinel at the boundary of the refractory. When a glaze layer is formed at the edge of a MgO refractory, the glaze layer will supply inclusions into liquid steel and may act as a protection layer for the refractory. Although the glaze could also react with dissolved Mn in steel to generate MnO in both the glaze and refractory, the MnO contents in both the glaze and refractory are evidently lower than that without glaze. The reaction between glazed MgO refractory and liquid steel is influenced by the basicity of the glaze layer. High-basicity slag would hinder the generation of MnO in both the glaze and refractory. Therefore, lower-basicity glaze needs to be avoided for the steelmaking process of medium-Mn steel grades. [ABSTRACT FROM AUTHOR]

Turbine blades, produced by the directional solidification (DS) process, often require high dimensional accuracy and excellent mechanical properties. A critical step in their production is the fabrication of wax patterns. However, the traditional manufacturing process has many disadvantages, such as long-term production, low material utilization rate, and the high cost of producing a complex-shaped wax pattern. Selective laser sintering (SLS) is one of the most extensively used additive manufacturing techniques that substantially shortens the production cycle. In this study, SLS was adopted to fabricate the wax pattern instead of the traditional manufacturing process. The orthogonal experiment method was carried out to investigate the effects of laser power, scanning speed, scanning space, and layer thickness on the dimensional precision and morphologies of the SLS parts. The SLS parts showed a minimum dimensional deviation when laser power, scanning speed, scanning space, and layer thickness were 10 W, 3000 mm ⋅ s[sup -1] , 0.18 mm, and 0.25 mm, respectively. In addition, the tensile strength and fracture morphologies were closely associated with the laser volumetric energy density (VED). The tensile strength reached a maximum when the VED was 0.0762 J ⋅ mm[sup -3] , with an evident brittle fracture morphology. The wax pattern manufactured in this way meets the accuracy and strength requirements for investment casting. This research offers a novel path for the production of wax patterns for complex-shaped turbine blades by SLS. [ABSTRACT FROM AUTHOR]

The current industrial ammonia synthesis relies on Haber–Bosch process that is initiated by the dissociative mechanism, in which the adsorbed N2 dissociates directly, and thus is limited by Brønsted–Evans–Polanyi (BEP) relation. Here we propose a new strategy that an anchored Fe3 cluster on the θ-Al2O3(010) surface as a heterogeneous catalyst for ammonia synthesis from first-principles theoretical study and microkinetic analysis. We have studied the whole catalytic mechanism for conversion of N2 to NH3 on Fe3/θ-Al2O3(010), and find that an associative mechanism, in which the adsorbed N2 is first hydrogenated to NNH, dominates over the dissociative mechanism, which we attribute to the large spin polarization, low oxidation state of iron, and multi-step redox capability of Fe3 cluster. The associative mechanism liberates the turnover frequency (TOF) for ammonia production from the limitation due to the BEP relation, and the calculated TOF on Fe3/θ-Al2O3(010) is comparable to Ru B5 site. [ABSTRACT FROM AUTHOR]

An n ×n interval matrix A = [A, A] is called to be a fuzzy interval matrix if 0 ≤ Aij ≤ Aij ≤ 1 for all 1 ≤ i, j ≤ n. In this paper, we proposed the notion of max-min algebra of fuzzy interval matrices. We show that the max-min powers of a fuzzy interval matrix either converge or oscillate with a finite period. Conditions for limiting behavior of powers of a fuzzy interval matrix are established. Some properties of fuzzy interval matrices in max-min algebra are derived. Necessary and sufficient conditions for the powers of a fuzzy interval matrices in max-min algebra to be nilpotent are proposed as well. [ABSTRACT FROM AUTHOR]

A polymolybdate-based metal-organic compound {H2[Cu2(L)2(Mo8O27)(H2O)4]} (1) [L = N-(pyridin-3-yl)isonicotinamide] has been synthesized under solvothermal (methanol-water mixed solvent) conditions and structurally characterized by singlecrystal X-ray diffraction. Compound 1 exhibits a 3D metal-organic network containing unusual 1D [ Mo8O27]n 6n- inorganic chains, with adjacent 1D chains connected by Cu(II) atoms and L ligands to form a 3D framework with a trinodal 4,4,6-connected {42.63.8}2{44.68.83} topology. The electrocatalytic activities of compound 1 and its photocatalytic properties for the degradation of organic dyes have also been investigated. [ABSTRACT FROM AUTHOR]

We first propose a scheme for controlled phase-flip gate between a flying photon qubit and the collective spin wave (magnon) of an atomic ensemble assisted by double-sided cavity quantum systems. Then we propose a deterministic controlled-not gate on magnon qubits with parity-check building blocks. Both the gates can be accomplished with 100% success probability in principle. Atomic ensemble is employed so that light-matter coupling is remarkably improved by collective enhancement. We assess the performance of the gates and the results show that they can be faithfully constituted with current experimental techniques. [ABSTRACT FROM AUTHOR]

We present mobile vehicle lidar observations in Tianjin, China during the spring, summer, and winter of 2016. Mobile observations were carried out along the city border road of Tianjin to obtain the vertical distribution characteristics of PM2.5. Hygroscopic growth was not considered since relative humidity was less than 60% during the observation experiments. PM2.5 profile was obtained with the linear regression equation between the particle extinction coefficient and PM2.5 mass concentration. In spring, the vertical distribution of PM2.5 exhibited a hierarchical structure. In addition to a layer of particles that gathered near the ground, a portion of particles floated at 0.6-2.5-km height. In summer and winter, the fine particles basically gathered below 1 km near the ground. In spring and summer, the concentration of fine particles in the south was higher than that in the north because of the influence of south wind. In winter, the distribution of fine particles was opposite to that measured during spring and summer. High concentrations of PM2.5 were observed in the rural areas of North Tianjin with a maximum of 350 µg m-3 on 13 December 2016. It is shown that industrial and ship emissions in spring and summer and coal combustion in winter were the major sources of fine particles that polluted Tianjin. The results provide insights into the mechanisms of haze formation and the effects of meteorological conditions during haze-fog pollution episodes in the Tianjin area. [ABSTRACT FROM AUTHOR]

We investigated the acidity and concentrations of water-soluble ions in PM2.5 aerosol samples collected from an urban site in Beijing and a rural site in Gucheng, Hebei Province from November 2016 to January 2017 to gain an insight into the formation of secondary inorganic species. The average SO42-, NO3-, and NH4+ concentrations were 8.3, 12.5, and 14.1 µg m-3, respectively, at the urban site and 14.0, 14.2, and 24.2 µg m-3, respectively, at the rural site. The nitrogen and sulfur oxidation ratios in urban Beijing were correlated with relative humidity (with correlation coefficient r = 0.79 and 0.67, respectively) and the aerosol loadings. Based on a parameterization model, we found that the rate constant of the heterogeneous reactions for SO2 on polluted days was about 10 times higher than that on clear days, suggesting that the heterogeneous reactions in the aerosol water played an essential role in haze events. The ISORROPIA II model was used to predict the aerosol pH, which had a mean (range) of 5.0 (4.9-5.2) and 5.3 (4.6-6.3) at the urban and rural site, respectively. Under the conditions with this predicted pH value, oxidation by dissolved NO2 and the hydrolysis of N2O5 may be the major heterogeneous reactions forming SO42- and NO3- in haze. We also analyzed the sensitivity of the aerosol pH to changes in the concentrations of SO42-, NO3-, and NH4+ under haze conditions. The aerosol pH was more sensitive to the SO42- and NH4+ concentrations with opposing trends, than to the NO3- concentrations. The sensitivity of the pH was relatively weak overall, which was attributed to the buffering effect of NH3 partitioning. [ABSTRACT FROM AUTHOR]

Topological nodal line semimetals, a novel quantum state of materials, possess topologically nontrivial valence and conduction bands that touch at a line near the Fermi level. The exotic band structure can lead to various novel properties, such as long-range Coulomb interaction and flat Landau levels. Recently, topological nodal lines have been observed in several bulk materials, such as PtSn4, ZrSiS, TITaSe2 and PbTaSe2. However, in two-dimensional materials, experimental research on nodal line fermions is still lacking. Here, we report the discovery of two-dimensional Dirac nodal line fermions in monolayer Cu2Si based on combined theoretical calculations and angle-resolved photoemission spectroscopy measurements. The Dirac nodal lines in Cu2Si form two concentric loops centred around the Γ point and are protected by mirror reflection symmetry. Our results establish Cu2Si as a platform to study the novel physical properties in two-dimensional Dirac materials and provide opportunities to realize high-speed low-dissipation devices. [ABSTRACT FROM AUTHOR]

Central shrinkage crack is a common defect encountered in steel ingot casting. It is necessary to limit the degree of crack in case of further propagation in forging. A 234-t steel ingot was dissected to check the internal quality, and a central shrinkage crack band of 1,400 mm in height and 120 mm in width, was found at a distance of 450 mm under the riser bottom line. Then, thermo-mechanical simulation using an elasto-viscoplastic finite-element model was conducted to analyze the stress-strain evolution during ingot solidification. A new criterion considering mush mechanical property in the brittle temperature range as well as shrinkage porosity was used to identify the shrinkage crack potential, where the degree of shrinkage porosity is regarded as a probability factor using a modified sigmoid function. Different casting processes, such as pouring speed, mould preheating and riser insulation, were optimized with the simulation model. The results show that fast pouring, proper mould preheating and good riser insulation can alleviate shrinkage crack potential in the ingot center. [ABSTRACT FROM AUTHOR]

Numerical heat-transfer and turbulent flow model for an industrial high-pressure gas quenching vacuum furnace was established to simulate the heating, holding and gas fan quenching of a low rhenium-bearing Ni-based single crystal turbine blade. The mesh of simplified furnace model was built using finite volume method and the boundary conditions were set up according to the practical process. Simulation results show that the turbine blade geometry and the mutual shielding among blades have significant influence on the uniformity of the temperature distribution. The temperature distribution at sharp corner, thin wall and corner part is higher than that at thick wall part of blade during heating, and the isotherms show a toroidal line to the center of thick wall. The temperature of sheltered units is lower than that of the remaining part of blade. When there is no shelteration among multiple blades, the temperature distribution for all blades is almost identical. The fluid velocity field, temperature field and cooling curves of the single and multiple turbine blades during gas fan quenching were also simulated. Modeling results indicate that the loading tray, free outlet and the location of turbine blades have important influences on the flow field. The high-speed gas flows out from the nozzle is divided by loading tray, and the free outlet enhanced the two vortex flow at the end of the furnace door. The closer the blade is to the exhaust outlet and the nozzle, the greater the flow velocity is and the more adequate the flow is. The blade geometry has an effect on the cooling for single blade and multiple blades during gas fan quenching, and the effects in double layers differs from that in single layer. For single blade, the cooing rate at thin-walled part is lower than that at thick-walled part, the cooling rate at sharp corner is greater than that at tenon and blade platform, and the temperature at regions close to the internal position is decreased more slowly than that close to the surface. For multiple blades in single layer, the temperature at sharp corner or thin wall in the blade that close to the nozzles is much lower, and the temperature distribution of blades is almost parallel. The cooling rate inside the air current channel is lower than that of at the position near blade platform and tenon, and the effect of blade location to the nozzles on the temperature field inside the blade is lower than that on the blade surface. For multiple blades in double layers, the flow velocity is low, and the flow is not uniform for blades in the second-layer due to the shielding of blades in the first-layer. the cooling rate of blades in the second-layer is lower than that in the first-layer. The cooling rate of blade close to the nozzles in the first-layer is the higher than that of blade away from the nozzles in the second-layer, and the temperature distribution on blades in the same layer is almost parallel. The cooling rate in thin wall position of blade away from the nozzles is larger than that in tenon of the blade closer to the nozzles in the same layer. The cooling rate for blades in the secondlayer is much lower both in thin wall and tenon for blades away from the nozzles. [ABSTRACT FROM AUTHOR]

P91 is a new kind of heat-resistant and high-tensile steel. It can be extruded after ingot casting and can be widely used for different pipes in power plants. However, due to its mushy freezing characteristics, a lack of feeding in the ingot center often generates many defects, such as porosity and crack. A six-ton P91 ingot was cast and sliced, and a representative part of the longitudinal section was inspected in more detail. The morphology of crack-like defects was examined by X-ray high energy industrial CT and reconstructed by 3D software. There are five main portions of defects larger than 200 mm³, four of which are interconnected. These initiated from continuous liquid film, and then were torn apart by excessive tensile stress within the brittle temperature range (BTR). The 3D FEM analysis of thermo-mechanical simulation was carried out to analyze the formation of porosity and internal crack defects. The results of shrinkage porosity and Niyama values revealed that the center of the ingot suffers from inadequate feeding. Several criteria based on thermal and mechanical models were used to evaluate the susceptibility of hot crack formation. The Clyne and Davies' criterion and Katgerman's criterion successfully predicted the high hot crack susceptibility in the ingot center. Six typical locations in the longitudinal section had been chosen for analysis of the stresses and strains evolution during the BTR. Locations in the defects region showed the highest tensile stresses and relative high strain values, while other locations showed either low tensile stresses or low strain values. In conclusion, hot crack develops only when stress and strain exceed a threshold value at the same time during the BTR. [ABSTRACT FROM AUTHOR]

Due to the extensive application of Al-Si alloys in the automotive and aerospace industries as structural components, an understanding of their microstructural formation, such as dendrite and (Al+Si) eutectic, is of great importance to control the desirable microstructure, so as to modify the performance of castings. Since previous major themes of microstructural simulation are dendrite and regular eutectic growth, few efforts have been paid to simulate the irregular eutectic growth. Therefore, a multiphase cellular automaton (CA) model is developed and applied to simulate the time-dependent Al-Si irregular eutectic growth. Prior to model establishment, related experiments were carried out to investigate the influence of cooling rate and Sr modification on the growth of eutectic Si. This CA model incorporates several aspects, including growth algorithms and nucleation criterion, to achieve the competitive and cooperative growth mechanism for nonfaceted-faceted Al-Si irregular eutectic. The growth kinetics considers thermal undercooling, constitutional undercooling, and curvature undercooling, as well as the anisotropic characteristic of eutectic Si growth. The capturing rule takes into account the effects of modification on the silicon growth behaviors. The simulated results indicate that for unmodified alloy, the higher eutectic undercooling results in the higher eutectic growth velocity, and a more refined eutectic microstructure as well as narrower eutectic lamellar spacing. For modified alloy, the eutectic silicon tends to be obvious fibrous morphology and the morphology of eutectic Si is determined by both chemical modifier and cooling rate. The predicted microstructure of Al-7Si alloy under different solidification conditions shows that this proposed model can successfully reproduce both dendrite and eutectic microstructures. [ABSTRACT FROM AUTHOR]

Three environment-assisted schemes are proposed to suppress the amplitude damping decoherence for entanglement distribution via weak measurement reversal. Based on the measurement of environment and appropriate weak measurement reversal operations, the initial entangled state can be recovered between two separated participants with high success probability and fidelity. In some specific cases, the restored optimal concurrence could reach up to 1 without requirement of the reversing measurement. Moreover, we concretely show that the proposed environment-assisted entanglement restoration can be applied to quantum teleportation to significantly improve the fidelity of the teleported state. [ABSTRACT FROM AUTHOR]

A microfluidic card is described for simultaneous and rapid genetic detection of multiple microbial pathogens. The hydrophobic surface of native acrylic and a novel microfluidic mechanism termed Bairlock^ were used to dispense sample into a series of 64 reaction wells without the use of valves, external pumping peripherals,multiple layers, or vacuum assistance. This airlock mechanism was tested with dilutions of whole human blood, saliva, and urine, along with mock samples of varying viscosities and surface tensions. Samples spiked with genomic DNA (gDNA) or crude lysates from clinical bacterial isolates were tested with loop mediated isothermal amplification assays (LAMP) designed to target virulence and antibiotic resistance genes. Reactions were monitored in real time using the Gene-Z, which is a portable smartphone-driven system. Samples loaded correctly into themicrofluidic card in 99.3%of instances. Amplification results confirmed no carryover of pre-dispensed primer between wells during sample loading, and no observable diffusion between adjacent wells during the 60 to 90 min isothermal reaction. Sensitivity was comparable between LAMP reactions tested within the microfluidic card and in conventional vials. Tests demonstrate that the airlock card works with various sample types, manufacturing techniques, and can potentially be used in many point-of-care diagnostics applications. [ABSTRACT FROM AUTHOR]

We propose a simple implementation scheme of quantum delayed-choice experiment in linear optical system without initial entanglement resource. By choosing different detecting devices, one can selectively observe the photon's different behaviors after the photon has been passed the Mach-Zehnder interferometer. The scheme shows that the photon's wave behavior and particle behavior can be observed with a single experimental setup by postselection, that is, the photon can show the superposition behavior of wave and particle. Especially, we compare the wave-particle superposition behavior and the wave-particle mixture behavior in detail, and find the quantum interference effect between wave and particle behavior, which may be helpful to reveal the nature of photonessentially. [ABSTRACT FROM AUTHOR]

We propose a scheme to prepare a maximally entangled state for two Λ-type atoms trapped in separate optical cavities coupled through an optical fiber based on the combined effect of the unitary dynamics and the dissipative process. Our work shows that the fiber loss, as well as the atomic spontaneous emission and the cavity decay, is no longer undesirable, but requisite to prepare the distributed entanglement, which is meaningful for the long distance quantum information processing tasks. Originating from an arbitrary state, the desired state could be prepared without precise time control. The robustness of the scheme is numerically demonstrated by considering various parameters. Graphical abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Technical standards are important documents for the development, application and expansion of any engineering material. In the casting industry, technical standards are the premise for producing high quality castings and they provide tools for inspection and acceptance of castings, and aid both the purchaser and the producer. In this paper, the most recent worldwide and Chinese technical standards for SG iron, ADI, CGI and heat resisting iron castings are described. It can be seen that these Chinese national standards have reached the level of world class standards. This will be beneficial for enhancing the Chinese foundry industry, improving Chinese casting quality and aid the supply of good quality castings to China's own industry. It is also good for the international buyer to source castings in China, and for the Chinese casting producer to export castings to other parts of the world. Current development trends for cast irons are also discussed. [ABSTRACT FROM AUTHOR]

The role of Body Mass Index (BMI) for Breast Cancer (BC) remains to be great interest for a long time. However, the precise effect of nonlinear dose-response for BMI and BC risk is still unclear. We conducted a dose-response meta-analysis to quantitatively assess the effect of BMI on BC risk. Twelve prospective studies with 4,699 cases identified among 426,199 participants and 25 studies of 22,809 cases identified among 1,155,110 participants in premenopausal and postmenopausal groups, respectively, were included in this meta-analysis. Significant non-linear dose-response (P, 0.001) association was identified between BMI and BC risk in postmenopausal women. Individuals with BMI of 25, 30, and 35 kg/m² yielded relative risks (RRs) of 1.02 [95% confidence interval (CI): 0.98-1.06], 1.12 (95% CI: 1.01-1.24), and 1.26 (95% CI: 1.07-1.50), respectively, when compared to the mean level of the normal BMI range. However, inverse result though not significant was observed in premenopausal women. In conclusion, the results of this meta-analysis highlighted that obesity contributed to increased BC risk in a nonlinear dose-response manner in postmenopausal women, and it is important to realize that body weight control may be a crucial process to reduce BC susceptibility. [ABSTRACT FROM AUTHOR]

Although the unique properties of wheat α-gliadin gene family are well characterized, little is known about the evolution and genomic divergence of α-gliadin gene family within the Triticeae. We isolated a total of 203 α-gliadin gene sequences from 11 representative diploid and polyploid Triticeae species, and found 108 sequences putatively functional. Our results indicate that α-gliadin genes may have possibly originated from wild Secale species, where the sequences contain the shortest repetitive domains and display minimum variation. A miniature inverted-repeat transposable element insertion is reported for the first time in α-gliadin gene sequence of Thinopyrum intermedium in this study, indicating that the transposable element might have contributed to the diversification of α-gliadin genes family among Triticeae genomes. The phylogenetic analyses revealed that the α-gliadin gene sequences of Dasypyrum, Australopyrum, Lophopyrum, Eremopyrum and Pseudoroengeria species have amplified several times. A search for four typical toxic epitopes for celiac disease within the Triticeae α-gliadin gene sequences showed that the α-gliadins of wild Secale, Australopyrum and Agropyron genomes lack all four epitopes, while other Triticeae species have accumulated these epitopes, suggesting that the evolution of these toxic epitopes sequences occurred during the course of speciation, domestication or polyploidization of Triticeae. [ABSTRACT FROM AUTHOR]

We demonstrate efficient processes of entanglement generation and quantum state transfer (QST) with dipole emitters coupled to a plasmonic double-bar resonator. The bipartite and multipartite maximal entanglement and complete QST can be deterministically achieved by selecting appropriate coupling strength between individual emitters and the resonator mode. Moreover, the entanglement dynamics show that high fidelities of entanglement generation and QST can be realized even under imprecise coupling strength and the system decay. The feasibility analysis and practical implementation are discussed, which manifest that our schemes may be meaningful for exploring solid-state quantum information processing with the metal plasmonic mode. [ABSTRACT FROM AUTHOR]

It has been known that the process of leaf senescence is accompanied by programmed cell death (PCD), and the previous study indicated that dark-induced senescence in detached leaves from rice led to the release of cytochrome f (Cyt f) from chloroplast into the cytoplasm. In this study, the effects of Cyt f on PCD were studied both in vitro and in vivo. In a cell-free system, purified Cyt f activated caspase-3-like protease and endonuclease OsNuc37, and induced DNA fragmentation. Furthermore, Cyt f-induced caspase-3-like activity could be inhibited by MG132, which suggests that the activity was attributed to the 26S proteasome. Conditional expression of Cyt f in the cytoplasm could also activate caspase-3-like activity and DNA fragmentation. Fluorescein diacetate staining and annexin V-FITC/PI double staining demonstrated that Cyt f expression in cytoplasm significantly increased the percentage of PCD protoplasts. Yeast two-hybrid screening showed that Cyt f might interact with E3-ubiquitin ligase and RPN9b, the subunits of the ubiquitin proteasome system (UPS), and other PCD-related proteins. Taken together, these results suggest that the released Cyt f from the chloroplast into the cytoplasm might activate or rescue caspase-3-like activity by interacting with the UPS, ultimately leading to the induction of PCD. [ABSTRACT FROM AUTHOR]

We present several efficient entanglement concentration protocols (ECPs) with the nitrogen-vacancy (N-V) centers coupled to low- Q microresonators. Based on the input-output process of ancillary coherent light pulse in low- Q microresonators, we can obtain the maximally entangled states among remote participants via local operations and classical communication. Our protocols use a conventional photon detector to discriminate the two coherent states | α〉 and |− α〉, which is more convenient than homodyne measurement. We discuss the feasibility of our protocols, and they may be beneficial for quantum repeaters and quantum information processing. [ABSTRACT FROM AUTHOR]

We propose theoretical schemes to generate n-electron GHZ state, n-electron cluster state, and four-electron | χ〉 state by using quantum-dot spins in double-sided optical microcavities. With single-photon detection and local unitary operations, these entangled states could be deterministically generated. The fidelities of our schemes are also calculated, which illustrate that our schemes have high performance under appropriate parameter conditions. [ABSTRACT FROM AUTHOR]

To substitute for petroleum, Fischer-Tropsch synthesis (FTS) is an environmentally benign process to produce synthetic diesel (n-paraffin) from syngas. Industrially, the synthetic gasoline (iso-paraffin) can be produced with a FTS process followed by isomerization and hydrocracking processes over solid-acid catalysts. Herein, we demonstrate a cobalt nano-catalyst synthesized by physical-sputtering method that the metallic cobalt nano-particles homogeneously disperse on the H-ZSM5 zeolite support with weak Metal-Support Interactions (MSI). This catalyst performed the high gasoline-range iso-paraffin productivity through the combined FTS, isomerization and hydrocracking reactions. The weak MSI results in the easy reducibility of the cobalt nano-particles; the high cobalt dispersion accelerates n-paraffin diffusion to the neighboring acidic sites on the H-ZSM5 support for isomerization and hydrocracking. Both factors guarantee its high CO conversion and iso-paraffin selectivity. This physical-sputtering technique to synthesize the supported metallic nano-catalyst is a promising way to solve the critical problems caused by strong MSI for various processes. [ABSTRACT FROM AUTHOR]

We propose a deterministic scheme to realize four-atom and five-atom cluster state analyzers based on the cavity input-output process. In the scheme, we construct a multi-qubit parity analyzer and two cluster state phase analyzers and show that all the orthogonal multi-atom cluster states can be completely identified in a nondestructive way by combining these two kinds of analyzers. The fidelities of analyzers are also calculated, which show that our scheme has a high performance in the intermediate coupling region. Furthermore, the scheme opens promising perspectives for large-scale Bell-state-measurement-based and cluster-state-measurement-based quantum communication and quantum information processing networks. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the importance of diffusion-weighted magnetic resonance imaging (DW-MRI) apparent diffusion coefficient (ADC) values to predict treatment response to neoadjuvant chemotherapy (NCT) in patients with locally advanced breast cancer (LABC). Thirty-two patients with LABC underwent 2-4 cylces of NCT (docetaxel and epirubicin). The DW-MRI scans were performed within one week prior to chemotherapy and after the first course of treatment, respectively. Accordingly, tumor volumes, changes in tumor ADC values, and their degree of correlation were analyzed. The overall response (OR) was observed in 62.5% (95% CI, 45.7-79.3%) of patients after 2 cycles of NCT. The clinical complete response (CR) rate and pathological CR (pCR) rate were 15.6 and 9.4%, respectively. The stable disease (SD) rate was 34.4% (11 patients), and progressive disease (PD) was observed in only one patient (3.1%). After the first cycle of NCT, the ADC values in the CR + PR group significantly increased ( P < 0.001). The initial ADC values before chemotherapy in the OR group were significantly lower than those in the SD + PD group ( P < 0.001). The initial ADC values and the changes in tumor volume after chemotherapy were negatively correlated ( r = −0.58, P = 0.02). The lower the initial tumor ADC value was the more obvious the decrease in tumor volume after chemotherapy. The changes in ADC values of tumors after chemotherapy and the changes in tumor volume were positively correlated ( r = 0.96, P < 0.001). After chemotherapy, the greater the change in ADC value, the more the tumor volume was reduced. Using the initial ADC values of breast cancer tumors and the early changes in ADC values after NCT, we may be able to predict tumor response to chemotherapy. Tumors with low initial ADC values may be sensitive to chemotherapy; tumors with significantly increasing ADC values early after chemotherapy may be sensitive to chemotherapy. [ABSTRACT FROM AUTHOR]

We propose explicit quantum circuits for implementing a positive operator valued measurement (POVM), by which a class of relatively general entanglement conversion can be realized determinately. Different from conventional method based on decomposition of unitary matrices, our implementation procedure involves decomposition of the evolution process from the initial state to the final state with quantum Toffoli gates. [ABSTRACT FROM AUTHOR]

We propose a scheme to joint remotely prepare arbitrary two- and three-particle entangled states by using non-maximally three-particle GHZ state as the quantum channel. Our scheme consists of two senders and one receiver. It will be shown that two senders can help the receiver to remotely prepare the original state with certain probability. The projective measurement and corresponding unitary operation are needed in this article. [ABSTRACT FROM AUTHOR]

For around 50 years, various approaches to the vidian neurectomy have been advocated. This indicates that there is no single surgical technique that is superior to all others. In this report, we analyze the included angle between the posterior end of middle turbinate and the anterior opening of the vidian canal. The aim of this paper is to use preoperative CT scanning to find a key anatomical structure to predict the feasibility of the vidian neurectomy. A retrospective research was performed. A total of 63 patients with 106 endoscopic vidian neurectomies between September 2006 and April 2010 were selected. The study population included 50 men and 13 women, with a mean age of 28. A paranasal sinus CT scan was obtained and analyzed. The included angle was measured and compared to the operating success rates. In the successful group (78 sides, 73.58%), the included angle from axial and coronal CT imaging was 30.2 ± 4.9° and 26.4 ± 9.1°, respectively. In the 28 failed sides (26.42%), the value was 33.8 ± 4.8° and 44.3 ± 8.1°, respectively. Statistical analysis confirmed that the difference between those two groups was significant ( P < 0.05). The present study reports the relationship between the vidian canal and the middle turbinate, which is represented by their included angle. The findings support the decision to intervene the surgical side with a smaller angle, because of the significantly higher success rate. [ABSTRACT FROM AUTHOR]