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Oil pollution and the energy crisis make oil-water separation an urgent for human need. The widespread use of materials with a single emulsion separation capability is limited. Multifunctional on-demand separation materials can adapt to a wide range of application scenarios, thus having a wider range of applications. The underoil superhydrophilic surface is of great significance for realizing the on-demand separation of oil/water emulsions through the removal of water in the oil and oil in the water. A 3D porous emulsion separation material based on the superhydrophilic principle of sphagnum moss was designed. The material was prepared in a simple step by taking advantage of the adhesion of polydopamine and the introduction of the as-prepared superhydrophilic BaSO4 nanoparticles to achieve superhydrophilicity with a water contact angle (WCA) of 0° and an oil contact angle (OCA) of 157.3°, resulting in excellent separation performance for both water-in-oil and oil-in-water emulsions. Underoil superhydrophilic porous composite (OSPC) can complete two kinds of emulsion separations by filtration or adsorption. It adsorbs water from water-in-oil emulsion to achieve separation, with a good adsorption capacity of 74.38 g/g and efficiency up to 99%. It can also filter oil-in-water emulsions with an efficiency of 99.92%. The separation efficiencies are all almost unchanged after ten separation cycles. Furthermore, the material has excellent flame retardancy, which reduces the possibility of secondary disasters. The three-dimensional porous sponge has excellent on-demand separation performance for multiple emulsions. It provides a new preparation strategy for underoil superhydrophilic materials and a new idea for the design direction of special wetting materials for the on-demand separation of oil/water emulsions. [ABSTRACT FROM AUTHOR]

Background: Flaxseed has been widely used in animal diets to increase the omega-3 polyunsaturated fatty acid content in animal products and promote overall animal health, but little known about its effects on the productive performance and the mictobita of gut of laying duck. Methods and results: Jinding duck, a Chinese indigenous breed, was used in the study. The corn-soybean basal diet supplemented with 0, 2%, 3% 4% and 5% flaxseed were provided to Control, 2% Fla, 3% Fla, 4% Fla and 5% Fla groups for 53 days, respectively. Compared with Control group, groups fed with flaxseed diets showed higher egg production, egg mass, ovary weight and more preovulatory follicles. The Docosahexaenoic Acid content of egg was extremely significantly elevated by flaxseed diets (P < 0.01), and the albumen height and haugh unit were elevated, especially in 4% Fla and/or 5% Fla group (P < 0.05). Groups 4% Fla and 5% Fla had highest ileal villus height, jejunal and ileal crypt depth. Moreover, Flaxseed diets significantly increased the levels of IgG and IgM in all Fla groups (P < 0.01), while increased IgA levels except for in 3% Fla group (P < 0.05). The results of 16s rDNA sequencing showed that flaxseed diet altered the microbial composition of gut and reduced the diversity and evenness of gut microbial communities except for 5% Fla. The correlation analysis identified Blautia, Butyricicoccus and Subdoligranulum positively associated with egg production. Genera Fourinierella, Fusobacterium and Intestinimonas positively associated with ovary weight, haught unit and album height. And Mucispirillum positively associated with haugh unit and album height. Conclusion: This study has suggested that flaxseed play a positive role in productive performance, the overall or intestinal health of laying ducks. [ABSTRACT FROM AUTHOR]

Mg3Sb2-based thermoelectrics show great promise for next-generation thermoelectric power generators and coolers owing to their excellent figure of merit (zT) and earth-abundant composition elements. However, the complexity of the defect microstructure hinders the advancement of high performance. Here, the defect microstructure is modified via In doping and prolonged sintering time to realize the reduced structural disorder and microstructural evolution, synergistically optimizing electron and phonon transport via a delocalization effect. As a result, an excellent carrier mobility of ~174 cm2 V−1 s−1 and an ultralow κ l a t of ~0.42 W m−1 K−1 are realized in this system, leading to an ultrahigh zT of ~2.0 at 723 K. The corresponding single-leg module demonstrates a high conversion efficiency of ~12.6% with a 425 K temperature difference, and the two-pair module of Mg3Sb2/MgAgSb displays ~7.1% conversion efficiency with a 276 K temperature difference. This work paves a pathway to improve the thermoelectric performance of Mg3Sb2-based materials, and represents a significant step forward for the practical application of Mg3Sb2-based devices. The authors modify complex defect microstructure in Mg3Sb2-based thermoelectrics to reduce structural disorder and promote microstructural evolution, synergistically optimizing electron and phonon transport via a delocalization effect for high performance. [ABSTRACT FROM AUTHOR]

To achieve consistent color reproduction of printed products and accurate measurement the content of mixed ink has always been an important research topic in the printing industry. This paper proposes a spectral-based method for measuring the content of dual-color mixed printing ink, aiming to solve the difficulty in determining the specific content of the base color in the same ratio of dual-color ink by using spectral analysis. First, a composite filtering method combining median filtering and wavelet transform was compared and selected for spectral preprocessing. Then, three methods, namely the successive projections algorithm (SPA), competitive adaptive reweighted sampling method (CARS), and stable competitive adaptive weighted sampling method (SCARS), were used to extract feature wavelengths from the preprocessed information. Based on partial least squares regression (PLSR), four models, PLSR, SPA–PLSR, CARS–PLSR, and SCARS, were established for predictive analysis. To further test the model, the SCARS–PLSR model was used for predictive analysis of magenta-cyan, yellow-magenta, and yellowcyan binary samples with a mass fraction ratio of 0.5. The results showed that the SCARS–PLSR model has the best predictive performance, with RMSE and R2 values of 0.0052, 0.0002, 0.0004 and 0.9989, 0.9999, 0.9999, respectively. This indicates that this study can accurately determine the content of dual-color ink by spectral analysis. [ABSTRACT FROM AUTHOR]

The regional ionospheric corrections have become one of the critical parts of Precise Point Positioning (PPP)-based Real-Time-Kinematic (RTK) services to achieve fast positioning convergence. Several methods for regional ionospheric corrections supporting PPP-RTK have been developed and implemented over recent years, but little attention is given to the theoretical foundation of existing ionospheric correction methods and their performance comparison to find an optimal method in some sense. The optimality criterion of such methods should not only be based on the precision of the ionospheric correction itself, but also on its broadcasting strategies, and implementation aspects. This contribution studies ionospheric correction generation methods within the best linear unbiased predictor (BLUP) framework. Comparing the accuracy performances of the methods, we demonstrate that the Kriging method with trend, as a special case of BLUP, is the most appropriate method for large-scale networks (above 500 km). A strategy for the evaluation of the uncertainty of the grid-interpolated ionospheric corrections is also developed. In contrast to other empirical methods, this new method is rigorous in the sense that it avoids the underestimation of the uncertainty of predicted ionospheric corrections, especially when reference stations are close to a grid point. [ABSTRACT FROM AUTHOR]

In this study, an experimental apparatus was designed to measure the thermochemical erosion properties of gun steel samples. Three tests were conducted in propellant gas to analyze the surface, cross-sectional morphology, and major element distribution. The results show that the specimen surface undergoes significant erosion by the hot gas, forming a porous white layer with a low melting point. The white layer's thickness and degree of damage increase with prolonged erosion time. During erosion, abundant amounts of carbon and oxygen migrate to the surface and bonded with iron. Carbonation reduces impact toughness, while oxidation increases metal volume, resulting in a more porous white layer. Consequently, many microcracks form within the white layer, which grow and intersect with deepening erosion. These findings suggest that surface erosion can lead to fracturing and breakage of the material, ultimately increasing exposure of the substrate to gas and accelerating the erosion rate. [ABSTRACT FROM AUTHOR]

In this paper, spherical single-crystal powder of Tb0.35Dy0.65Fe1.9 alloy was prepared by combining solid/liquid unwetting effect and anomalous grain growth, and the Tb0.35Dy0.65Fe1.9/epoxy composite was prepared under an applied magnetic field at 1.0 T. SEM observed that the prepared Tb0.35Dy0.65Fe1.9 alloy powder was spherical (sphere-like). XRD shows that the composites with 50% volume fraction of powder particles have a high < 111 > orientation, magnetostriction measurements showed that the composites prepared from spherical single-crystal powder treated with titanate coupling agent exhibited a high low-field magnetostriction coefficient of 464 ppm at 1 kOe magnetic field, which is 83 ppm higher than the spherical single-crystal powder composites without any treatment, an improvement of 21%. [ABSTRACT FROM AUTHOR]

In previous studies on multiple hypothesis solution separations (MHSS) advanced autonomous integrity monitoring (ARAIM) in phase-based GNSS precise point positioning (PPP)-real-time kinematic (RTK), the risk of wrong (or incorrect) ambiguity fixing is generally considered to be negligible after ambiguity validation. However, this unrealistic assumption can introduce risks to PPP-RTK positioning solutions that have strict requirements for accuracy and integrity. In this study, a new integrity monitoring method considering the risks of wrong ambiguity fixing is proposed. The proposed method extends the scope of ARAIM to accommodate a type of pseudo-measurements for integer ambiguity fixing. Then, wrong ambiguity fixing can be treated as a type of fault in the MHSS ARAIM scheme. We test the proposed integrity monitoring method with both simulated and real-world PPP-RTK data sets, demonstrating that this method is conservative and can properly bound the positioning errors. Additionally, we analyze the effect of the probability of wrong ambiguity fixing on PPP-RTK positioning protection levels (PLs). The numerical results show that when the probability of wrong ambiguity fixing is smaller than the magnitude of the integrity budget, the effects on PLs are usually very small. On the contrary, due to the impact of wrong integer ambiguity fixing risks, it can increase the PLs levels of ambiguity-fixed solutions, which however will still be smaller than the PLs of ambiguity-float solutions. [ABSTRACT FROM AUTHOR]

Apple growth and development can be impacted by abiotic factors, including low temperature and dryness. Plant responses to stressors are heavily influenced by inducer of CBF expression (ICE) transcription factors (TFs). Malus baccata (L.) Borkh (M. baccata) was used in this investigation to isolate the MbICE3 new ICE gene. The molecular weight of MbICE3 was anticipated to be 56.47 kDa, and its open reading frame (ORF) had 519 amino acids (aa) and 1560 base pairs (bp). Subcellular localization revealed that MbICE3 was concentrated in the nucleus. Cold and drought stresses significantly affected the expression levels of MbICE3, and the first heterologous expression of MbICE3 in lettuce (Lactuca sativa L.) could significantly improve its tolerance to cold and drought stresses. In comparison to wild-type (WT) and unloaded lines (UL) lettuce, the transgenic plants had increased proline and chlorophyll concentrations as well as higher superoxide dismutase (SOD) and peroxidase (POD) activity when subjected to cold and drought. However, compared to WT and UL, transgenic lettuce had lower levels of malondialdehyde (MDA) and O2− content. Furthermore, it was found that under drought and low temperature stress, MbICE3 positively regulated the expression of LsCBFs genes. These results suggest that MbICE3 actively contributes to plant tolerance to cold and drought. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (NPs) are widely used in biomedicine, catalysis, environment, electronics, and other fields, which is closely related to its structural form. For this purpose, researchers have been looking for a simple, green, and controllable way to mass produce metal nanomaterials with desired characteristics (shape, size, stability, etc.). Due to the surface plasmon resonance (SPR) effect of metal nanoparticles, photoreduction method can control the morphology of metal nanoparticles well, which is also simple, large-scalable, and energy-saving. This review provides an overview of the photoreduction method for the synthesis of metal nanoparticles and discusses the factors such as the light source, pH value, reagents, and temperature on the morphology of the nanoparticles. Finally, the challenges and development trends in the controlled preparation of nanomaterials are proposed. [ABSTRACT FROM AUTHOR]

Eusocial pollinators are crucial elements in global agriculture. The honeybees and bumblebees are associated with a simple yet host-restricted gut community, which protect the hosts against pathogen infections. Recent genome mining has led to the discovery of biosynthesis pathways of bioactive natural products mediating microbe-microbe interactions from the gut microbiota. Here, we investigate the diversity of biosynthetic gene clusters in the bee gut microbiota by analyzing 477 genomes from cultivated bacteria and metagenome-assembled genomes. We identify 744 biosynthetic gene clusters (BGCs) covering multiple chemical classes. While gene clusters for the post-translationally modified peptides are widely distributed in the bee guts, the distribution of the BGC classes varies significantly in different bee species among geographic locations, which is attributed to the strain-level variation of bee gut members in the chemical repertoire. Interestingly, we find that Gilliamella strains possessing a thiopeptide-like BGC show potent activity against the pathogenic Melissococcus plutonius. The spectrometry-guided genome mining reveals a RiPP-encoding BGC from Gilliamella with a 10 amino acid-long core peptide exhibiting antibacterial potentials. This study illustrates the widespread small-molecule-encoding BGCs in the bee gut symbionts and provides insights into the bacteria-derived natural products as potential antimicrobial agents against pathogenic infections.Here, by characterizing 477 genomes from cultivated bacteria and metagenome-assembled genomes of the bee gut microbiota, the authors uncover uncharacterized biosynthetic gene clusters encoding small molecules with potential antimicrobial activity against bee pathogens, shedding light on the role of microbiome in honeybee health. [ABSTRACT FROM AUTHOR]

From the perspective of the deep reinforcement learning algorithm, the training effect of the agent will be affected because of the excessive randomness of the ε-greedy method. This paper proposes a novel action decision method to replace the ε-greedy method and avoid excessive randomness. First, a confidence bound span fitting model based on a deep neural network is proposed to fundamentally solve the problem that UCB cannot estimate the confidence bound span of each action in high-dimensional state space. Then, a confidence bound span balance model based on target value in reverse order is proposed. The parameters of the U network are updated after each action decision using the backpropagation of the neural network to balance the confidence bound span. Finally, an exploration-exploitation dynamic balance factor α is introduced to balance exploration and exploitation in the training process. Experiments are conducted using the Nature DQN and Double DQN algorithms, and the results demonstrate that the proposed method achieves higher performance than the ε-greedy method under the basic algorithm and experimental environment of this paper. The method presented in this paper has significance for applying a confidence bound to solve complex reinforcement problems. [ABSTRACT FROM AUTHOR]

To investigate the formation and development characteristics of the white layer on a gun exposed to erosive and high-temperature propellant gas, an experiment was conducted, and a transient model comprising chemical reactions was established. The numerical results showed a close agreement with the experiment, with a maximum error of 8%. The results suggest that the development of the white layer is primarily influenced by surface carburization under experimental conditions. Moreover, the carbon content and thickness of the white layer monotonically increase, displaying a logarithmic relationship with erosion time. The carbon content is the highest on the surface and decreases rapidly with depth. Furthermore, the growth rate of the white layer is found to correlate positively with the temperature of the propellant gas. When the temperature approaches the melting point of cementite, the surfaces of the samples become softened, leading to an enhanced diffusion rate of carbon to the deep layers. This phenomenon promotes cementite formation, accelerating the white layer's development. [ABSTRACT FROM AUTHOR]

Ecological ditches are a typical ecological facility for controlling road stormwater runoff pollution; they mainly remove harmful pollutants from runoff through plant absorption, retention and sedimentation, ecological adsorption, and microbial action. In this paper, according to the transport form of rainwater in the ditches, the removal effects of two different types of ditches on nitrogen, phosphorus, heavy metals, and other pollutants were simulated under three conditions of rainfall, slow flow, and still water, respectively, and their operating characteristics were analyzed. The results showed that the removal rate of TN in the two ecological ditches under slow flow conditions showed a downward trend as a whole with the increase of hydraulic load, and the suitable hydraulic load for TN removal should be selected as 0.3 m3/(m2 day). Under the simulated rainfall conditions, the TN removal rates of no. 1 and no. 2 ditches were 26.1–37.2% and 24.9 ~ 52.5%, respectively, and the TP removal rates were 44.6 ~ 63.3% and 36.1 ~ 62.1%. After 19.4 h and 22.1 h in the static state, the TP concentration in no. 1 ditch and no. 2 ditch reached the surface V water standard, and the average removal rate of TP was 74.7% and 53.7%, respectively. This paper provides a reference for selecting suitable parameters and optimizing the operational performance of ecological ditches to reduce runoff pollutants more effectively. [ABSTRACT FROM AUTHOR]

The modification of the electronic band structure is of critical importance for thermoelectric materials whose heat to electricity power generation is related to carrier effective mass and alignment of semiconductor band edges. One approach to optimize the electronic band structure is by modification of orbital interactions through doping or alloying. While the current ab-initio quantum chemical calculations can help us to investigate orbital components of electronic bands, they reveal little information on the relative tunability of electronic states and transport properties with respect to orbital interactions. In this work, we present a method, based on a symmetry-adapted tight-binding model and sensitivity analysis, that can pinpoint the role of orbital interactions in determining electronic band structure and transport properties. As an application, a systematic theoretical analysis is used to show how the power factor of PbTe can/cannot be improved by playing with interatomic orbital interactions. The orbital interaction sensitivity analysis introduced in this work can easily be applied to other compounds or properties. [ABSTRACT FROM AUTHOR]

The Arctic Ocean's Beaufort Gyre (BG) is a wind-driven reservoir of relatively fresh seawater, situated beneath time-mean anticyclonic atmospheric circulation, and is covered by mobile pack ice for most of the year. Liquid freshwater accumulation in and expulsion from this gyre is of critical interest due to its potential to affect the Atlantic meridional overturning circulation and due to the importance of freshwater in modulating vertical fluxes of heat, nutrients and carbon in the ocean, and exchanges of heat and moisture with the atmosphere. Here, we investigate the hypothesis that wind-driven sea ice transport into/from the BG region influences the freshwater content of the gyre and its variability. To test this hypothesis, we use the results of a coordinated climate response function experiment with four ice-ocean models, in combination with targeted experiments using a regional setup of the MITgcm, in which we rotate the surface wind forcing vectors (thereby changing the ageostrophic component of these winds). Our results show that, via an effect on the net thermodynamic growth rate, anomalies in sea ice transport into the BG affect liquid freshwater adjustment. Specifically, increased ice import increases freshwater retention in the gyre, whereas ice export decreases freshwater in the gyre. Our results demonstrate that uncertainty in the ageostrophic component of surface winds, and in the dynamic sea ice response to these winds, has important implications for ice thermodynamics and freshwater. This sensitivity may explain some of the observed inter-model spread in simulations of Beaufort Gyre freshwater and its adjustment in response to wind forcing. [ABSTRACT FROM AUTHOR]

The substrate and thin-walled components experience significant residual stress and deformation during the arc additive manufacturing, and the aggravation of substrate deformation impacts the performance of thin-walled components. In this paper, a novel method of preheating the substrate is proposed by using plasma arc to reduce the residual stress in the fabrication of thin-walled components. By employing COMSOL® Multiphysics software, a single multilayer 3D thermo-mechanical coupling model for additive manufacturing (AM) is developed and combined with the digital image correlation (DIC) method. The interaction law among temperature field, stress field and strain field of 304 stainless steel thin-wall part are studied in detail. In addition, the process of reducing stress and strain by arc preheating is investigated. The results show that the arc preheating before AM reduces the residual stress in the thin-walled parts and the joint between the thin-walled parts and the substrate. Moreover, it decreases the deformation of the thin-walled parts and the substrate. [ABSTRACT FROM AUTHOR]

Purpose: Classical prognostic indicators of head and neck squamous cell carcinoma (HNSCC) can no longer meet the clinical needs of precision medicine. This study aimed to establish a radiomics model to predict Granzyme A (GZMA) expression in patients with HNSCC. Methods: We downloaded transcriptomic data of HNSCC patients from The Cancer Genome Atlas for prognosis analysis and then used corresponding enhanced computed tomography (CT) images from The Cancer Imaging Archive for feature extraction and model construction. We explored the influence of differences in GZMA expression on signaling pathways and analyzed the potential molecular mechanism and its relationship with immune cell infiltration. Subsequently, non-invasive CT radiomics models were established to predict the expression of GZMA mRNA and evaluate the correlation with the radiomics-score (Rad-score), related genes, and prognosis. Results: We found that GZMA was highly expressed in tumor tissues, and high GZMA expression was a protective factor for overall survival. The degree of B and T lymphocyte and natural killer cell infiltration was significantly correlated with GZMA expression. The receiver operating characteristic curve showed that the Relief GBM and RFE_GBM radiomics models had good predictive ability, and there were significant differences in the Rad-score distribution between the high- and low-GZMA-expression groups. Conclusions: GZMA expression can significantly affect the prognosis of patients with HNSCC. Enhanced CT radiomics models can effectively predict the expression of GZMA mRNA. [ABSTRACT FROM AUTHOR]

Expansive slurry has attracted more and more attention because it can compensate for the reduction of the grouting reinforcement effect caused by dry shrinkage of cement, but the reinforcement mechanism of expansive slurry is still incompletely understood. To study the grouting reinforcement mechanism of expansive slurry, both direct shear tests and numerical tests were carried out for the slurry-fractured rock mass composite. The results show that the expansive slurry grouting reinforcement has a remarkable shear strength increase of 30.53% than the ordinary slurry. The expansion stress and the normal stress increased the friction at the interface, which also improve the ability of the expansive slurry-fractured rock mass composite interface to resist deformation and reduce the tensile failure area on the surface of the composite. During the shear test, the expansion stress can be regarded as the increase of normal stress, which changed the stress distribution inside the composite, reduced the porosity of the expansive slurry near the interface, and increased the friction against the failure of the composite and the internal friction angle at the slurry-rock interface. These promote an increase in shear strength and improve the grouting effect. The investigation of the grouting reinforcement mechanism of expansive slurry provides a technical approach for the application of grouting reinforcement and support in underground engineering. Highlights: Both the direct shear tests and numerical tests show that expansive slurry can effectively strengthen the single fractured rock mass. DIC technology and numerical method were used to present the failure evolution process of grouting the single fractured rock mass, indicating that the failure mode is dominated by tensile failure. The grouting reinforcement mechanism of the single fractured rock mass was revealed using the Mohr–Coulomb criterion. [ABSTRACT FROM AUTHOR]

Accurate assessment of soil C storage patterns and control factors on a regional and global scale is essential for predicting and mitigating soil C feedback to global environmental change. We used soil samples collected in the Shiyang River Basin in 2018, combined with remote sensing data, climate and meteorological data, watershed hydrological data, and soil physical and chemical properties to discuss the change characteristics and influencing factors of soil organic carbon (SOC) under different soil depths in the Shiyang River Basin in an arid area and analyze the storage model and carbon sequestration potential of soil organic carbon in different geomorphic units. The research results show that, (1) in spatial distribution, the SOC content in the Shiyang River Basin shows an obvious regional difference, and the average content of SOC in the oasis area in the middle reaches significantly higher than that in the mountain area in the upstream and desert area in the downstream. In vertical distribution, the content of SOC in the whole watershed decreases with the soil depth increase. (2) Soil carbon sequestration potential decreased with the increase in soil depth, but there were regional differences. The Oasis area in the middle reaches of the Shiyang River Basin is a high-potential area. In contrast, most of the upper mountain areas and the lower reaches of the desert area are low-potential areas. Environmental factors such as vegetation cover, meteorological factors, and physical and chemical properties of soil are important factors that promote the spatial variability of SOC content. The decisive effect of environmental factors on the SOC content is most significant in the surface layer 0–20 cm. [ABSTRACT FROM AUTHOR]

Nosema ceranae is an intracellular parasite invading the midgut of honeybees, which causes serious nosemosis implicated in honeybee colony losses worldwide. The core gut microbiota is involved in protecting against parasitism, and the genetically engineering of the native gut symbionts provides a novel and efficient way to fight pathogens. Here, using laboratory-generated bees mono-associated with gut members, we find that Snodgrassella alvi inhibit microsporidia proliferation, potentially via the stimulation of host oxidant-mediated immune response. Accordingly, N. ceranae employs the thioredoxin and glutathione systems to defend against oxidative stress and maintain a balanced redox equilibrium, which is essential for the infection process. We knock down the gene expression using nanoparticle-mediated RNA interference, which targets the γ-glutamyl-cysteine synthetase and thioredoxin reductase genes of microsporidia. It significantly reduces the spore load, confirming the importance of the antioxidant mechanism for the intracellular invasion of the N. ceranae parasite. Finally, we genetically modify the symbiotic S. alvi to deliver dsRNA corresponding to the genes involved in the redox system of the microsporidia. The engineered S. alvi induces RNA interference and represses parasite gene expression, thereby inhibits the parasitism significantly. Specifically, N. ceranae is most suppressed by the recombinant strain corresponding to the glutathione synthetase or by a mixture of bacteria expressing variable dsRNA. Our findings extend our previous understanding of the protection of gut symbionts against N. ceranae and provide a symbiont-mediated RNAi system for inhibiting microsporidia infection in honeybees. Microsporidia parasitism affect honeybees health and has been implicated in colony losses. Here, the authors show that members of the honeybee gut microbiota inhibit microsporidia proliferation, and engineer a gut symbiont that protects against Nosema ceranae infection via inhibiting its redox system. [ABSTRACT FROM AUTHOR]

Integrity monitoring for precise point positioning is critical for safety-related applications. With the increasing demands of high-accuracy autonomous navigation for unmanned ground and aerial vehicles, the integrity monitoring method of high-precision positioning has become an essential requirement. While high precision Global Navigation Satellite Systems (GNSS) positioning is widely used in such applications, there are still many difficulties in the integrity monitoring method for the multi-frequency multi-GNSS undifferenced and uncombined Precise Point Positioning (PPP). The main difficulties are caused by using the measurements of multiple epochs in PPP. Based on the baseline Multiple Hypothesis Solution Separation (MHSS) Advanced Receiver Autonomous Integrity Monitoring (ARAIM) algorithm, this paper discusses the feasibility of the pseudorange-based baseline ARAIM method on the single-epoch PPP based on Real-Time Kinematic (RTK) networks (PPP-RTK) framework to overcome these difficulties. In addition, a new scheme is proposed to transfer the conventional PPP process into the single-epoch PPP-RTK framework. The simulation results using the proposed model are analyzed in this study. The Protection Levels (PLs) estimated by PPP Wide-lane Ambiguity Resolution (PPP-WAR) model with regional corrections can reach the meter level and the PLs estimated by PPP Ambiguity Resolution (PPP-AR) and PPP-RTK models are usually the sub-meter level. Given a horizontal Alert Limit (AL) of 1.5 m, the global coverage of availability above 99.9% for PPP-WAR, PPP-AR, and PPP-RTK can reach 92.6%, 99.4%, and 99.7% respectively. The results using real kinematic data also show that tight PLs can be achieved when the observation conditions are good. [ABSTRACT FROM AUTHOR]

The precise point positioning (PPP)-based real-time-kinematic (RTK) method attracts increasing attention from both academia and industry because of its potential for high accuracy positioning with a shorter convergence time compared to the traditional PPP. Besides high accuracy, integrity monitoring (IM) is indispensable for safety–critical real-time land vehicle and aviation applications. As the traditional advanced receiver autonomous integrity monitoring (ARAIM) method is designed for (smoothed) pseudorange-based positioning, the complexity of multi-frequency multi-constellation PPP-RTK using carrier phase measurements has not been given sufficient consideration. This study proposes an IM scheme for multi-frequency multi-constellation uncombined PPP-RTK applying the ARAIM theory, with a new comprehensive threat model to accommodate not only pseudorange measurements, but also carrier phase measurements, and other fault events arising from the network corrections that support PPP-RTK. Characteristics of different types of faults are analyzed with the aid of numerical experiments. In addition, the impact of ambiguity-fixed solutions on PPP-RTK integrity performance is investigated. The authors have also conducted case studies, including static and real-kinematic positioning experiments. Experiments have demonstrated that fast convergence in accuracy and the position error bounds, or protection levels, with a given integrity risk, in horizontal position components of PPP-RTK could be achieved. For the open sky environments on a highway, the protection levels estimated by PPP-RTK solutions have the potential to meet the alert limit requirement for road transportation using ambiguity-fixed PPP-RTK positioning under the assumption that the risks of wrong ambiguity fixing are very small and can be ignored. [ABSTRACT FROM AUTHOR]

B-cell lymphoma 10 (Bcl10) is a scaffolding protein that functions as an upstream regulator of NF-κB signaling by forming a complex with Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (Malt1) and CARD-coiled coil protein family. This study showed that Bcl10 was involved in type I interferon (IFN) expression in response to DNA virus infection and that Bcl10-deficient mice were more susceptible to Herpes simplex virus 1 (HSV-1) infection than control mice. Mechanistically, DNA virus infection can trigger Bcl10 recruitment to the STING-TBK1 complex, leading to Bcl10 phosphorylation by TBK1. The phosphorylated Bcl10 undergoes droplet-like condensation and forms oligomers, which induce TBK1 phosphorylation and translocation to the perinuclear region. The activated TBK1 phosphorylates IRF3, which induces the expression of type I IFNs. This study elucidates that Bcl10 induces an innate immune response by undergoing droplet-like condensation and participating in signalosome formation downstream of the cGAS-STING pathway. [ABSTRACT FROM AUTHOR]

Agricultural water accounts for more than 80% of the available water in arid areas. Agricultural activities have a great impact on surface water and groundwater. If the impact of agricultural activities on hydrochemistry is not prevented, the risk of water quality change in arid areas may be greatly intensified. Based on the hydrochemical data of the whole Shiyang River Basin from April 2014 to October 2019, this paper analyzes the impact of agricultural activities on hydrochemistry in the basin. The results show that (i) in the middle and lower reaches of farmland with high intensity of agricultural activities, the ion concentration of groundwater in summer and autumn is significantly higher than that in winter and spring due to the influence of irrigation; (ii) the runoff ion concentration in the backflow of the river reaches recharged by irrigation water is significantly higher than that of other reaches; (iii) due to strong evaporation, different types of reservoirs will lead to an overall increase in ion concentration, which is more obvious in plain reservoirs and river tail lakes. In addition, the reservoirs have a certain removal effect on nitrates. [ABSTRACT FROM AUTHOR]

The middle and lower reaches of Hanjiang River Basin (MLHB), areas that have an important ecological function in China, have experienced great changes in the vegetation ecosystem driven by natural environmental change and human activity. Here, we explored the spatio-temporal dynamics of fractional vegetation coverage (FVC) and quantitatively analyzed its driving factors to advance current understanding of how the ecological environment has changed. Specifically, we used the dimidiate pixel model to calculate the FVC of the MLHB from 2001 to 2018 based on Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) data. We then used Theil–Sen median slope (Sen's slope) and coefficient of variation (CV) to explore spatial and temporal variations, as well as characteristics in fluctuations. Finally, we utilized a geographical detector model (with spatial scale effects and spatial data discretization tests) to quantify the influence of the detected natural and human factors. Results showed that average annual FVC was 0.30–0.75 for ~90% of the study area over the 19-year study period with a heterogeneous spatial distribution. FVC variation trend displayed stability and improvement. Areas with higher FVC displayed greater stability. All 10 detected natural and anthropogenic factors were responsible for changes in FVC. The primary factors causing FVC to change were precipitation (in 2001) and slope (in 2018), followed by landform type, distance to water, and nighttime light (NTL) (in 2018). Precipitation and slope consistently displayed the largest interaction across all years. The interaction between human and topographical factors had gradually increasing significance on changes in FVC over the research period. The range and type of factors suitable for promoting vegetation growth were detected in the study area. Results of this study can provide a scientific basis for developing effective strategies for local vegetation protection, restoration, and land resource management. [ABSTRACT FROM AUTHOR]

In this study, M-type Sr1–xLaxFe12O19 (x = 0.00–0.15) ferrite was prepared by traditional solid-phase sintering. Based on the amount of doping, we used X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and vibration sample magnetometer characterization to study the regular changes in the microstructure and magnetic properties at the optimal temperature. The results demonstrate that all the samples had an M-type strontium ferrite structure and good morphology, with the typical hexagonal plate-like grains. With the increase of lanthanum element, the grain size was also refined. Furthermore, FTIR confirmed the formation of tetrahedrons and octahedrons with a ferrite structure, and the magnetic performance and coercive force were improved (702.2 Oe) when the saturation magnetization loss (0.547 emu/g) was low. [ABSTRACT FROM AUTHOR]

It is critical for hospitals to accurately predict patient length of stay (LOS) and mortality in real-time. We evaluate temporal convolutional networks (TCNs) and data rebalancing methods to predict LOS and mortality. This is a retrospective cohort study utilizing the MIMIC-III database. The MIMIC-Extract pipeline processes 24 hour time-series clinical objective data for 23,944 unique patient records. TCN performance is compared to both baseline and state-of-the-art machine learning models including logistic regression, random forest, gated recurrent unit with decay (GRU-D). Models are evaluated for binary classification tasks (LOS > 3 days, LOS > 7 days, mortality in-hospital, and mortality in-ICU) with and without data rebalancing and analyzed for clinical runtime feasibility. Data is split temporally, and evaluations utilize tenfold cross-validation (stratified splits) followed by simulated prospective hold-out validation. In mortality tasks, TCN outperforms baselines in 6 of 8 metrics (area under receiver operating characteristic, area under precision-recall curve (AUPRC), and F-1 measure for in-hospital mortality; AUPRC, accuracy, and F-1 for in-ICU mortality). In LOS tasks, TCN performs competitively to the GRU-D (best in 6 of 8) and the random forest model (best in 2 of 8). Rebalancing improves predictive power across multiple methods and outcome ratios. The TCN offers strong performance in mortality classification and offers improved computational efficiency on GPU-enabled systems over popular RNN architectures. Dataset rebalancing can improve model predictive power in imbalanced learning. We conclude that temporal convolutional networks should be included in model searches for critical care outcome prediction systems. [ABSTRACT FROM AUTHOR]

Among cancers, lung cancer is the most common cause of death in China. For the prevention and control of lung cancer, it is necessary to investigate the spatial and temporal distribution of lung cancer mortality, as well as the changes in the trend and the affecting mechanism. Based on statistics and auto-correlation analysis, this paper studied the spatial and temporal distribution of lung cancer mortality in Yuhui District, Bengbu, Huaihe River Basin, from 2017 to 2020. In addition, Spearman's Rank Correlation Assessment Model and Geographic Detector Model were used to examine the relationship between environmental factors and lung cancer mortality to identify impact factors and their mechanisms. The findings indicated that: 1) from the characteristics of temporal distribution, the number of lung cancer deaths exhibited a linear growth tendency, with the highest mortality in winter; 2) from the characteristics of spatial distribution, lung cancer mortality showed a strong spatial agglomeration form, concentrating on two clustering areas, located in the old city and the central city of Bengbu, near the Huaihe River; 3) from the point of view of the whole research area, there were 15 impact factors with significant correlation in the built and natural environment factors. The significant impacting factors in the built environment included land use, road traffic, spatial form and blue-green space, which could indirectly affect lung cancer mortality, while air pollution and temperature constituted the significant impacting factors in the natural environment; 4) the influence of screened environmental factors on lung cancer mortality was different. Spatial stratified heterogeneity assessment, the interaction among environmental factors demonstrated statistical significance, it was found that the interaction between environmental factors in pairs had a significant enhancement effect on lung cancer mortality. To some extent, urban planning and policies could reduce lung cancer mortality. [ABSTRACT FROM AUTHOR]

Marginal zone lymphoma (MZL) is an uncommon subtype of non-Hodgkin lymphoma (NHL). Combination of rituximab and cladribine (R-2CdA) is a potential option for indolent NHL (iNHL) and mantle cell lymphoma (MCL) patients. The goal of this multicenter retrospective study was to assess the efficacy and safety of R-2CdA in MZL to support consensus-reaching in first-line therapy in advanced-stage patients. We searched electronic medical records databases of eight centers in China. Between November 2014 and December 2019, 183 symptomatic advanced MZL patients (42 treated with R-2CdA and 141 with rituximab plus cyclophosphamide, adriamycin, vincristine, and prednisone [R-CHOP]) were identified. After propensity score matching (PSM) (1:1) to adjust for clinical characteristics, 39 patients from each treatment arm were selected. The overall response rate (ORR) (84.6% vs. 94.9%, P = 0.263) and complete response rate (59.0% vs. 66.7%, P = 0.487) were comparable between two protocols. Neither progression-free survival (PFS), including the 5-year PFS (67.7% vs. 56.1%, P = 0.352), nor overall survival was improved by R-2CdA versus R-CHOP. However, R-2CdA was more tolerable than R-CHOP in MZL patients regarding grade 3/4 hematological adverse events (odds ratio [OR] 0.565, 95% confidence interval [CI] neutropenic fever (OR 0.795, 95% CI 0.678-0.932), and infections (OR 0.800, 95% CI 0.640-1.000). Overall, our study demonstrated that R-2CdA is potentially as effective as but safer than R-CHOP in advanced MZL. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma (CCA) is a highly malignant disease with a poor prognosis, and mechanisms of initiation and development are not well characterized. It is long noncoding RNAs (lncRNAs) acting as miRNA decoys to regulate cancer-related RNAs in competing endogenous RNA (ceRNA) networks that suggest a possible molecular mechanism in CCA. The current study aims to find potential prognosis biomarkers and small molecule therapeutic targets based on the construction of a CCA prognosis-related ceRNA network. A transcriptome dataset for CCA was downloaded from the TCGA database. Differentially expressed lncRNAs (DElncRNAs), DEmiRNAs and DEmRNAs were identified based on the differential expression and a DEceRNA network was constructed using predicted miRNA-lncRNA and miRNA-mRNA interactions. Heat maps, PCA analysis, and Pathway enrichment analysis and GO enrichment analysis were conducted. The prognostic risk model and molecular docking were constructed based on identified key ceRNA networks. A DElncRNA-miRNA-mRNAs network consisting of 434 lncRNA-miRNA pairs and 284 miRNA-mRNA pairs with 200 lncRNAs, 21 miRNAs, and 245 mRNAs was constructed. There were three lncRNAs (AC090772.1, LINC00519, and THAP7-AS1) and their downstream mRNAs (MECOM, MBNL3, RCN2) screened out as prognostic factors in CAA. Three key networks (LINC00519/ hsa-mir-22/ MECOM, THAP7-AS1/hsa-mir-155/MBNL3, and THAP7-AS1/hsa-mir-155/RCN2) were identified based on binding sites prediction and survival analysis. A prognostic risk model was established with a good predictive ability (AUC = 0.66–0.83). Four anticancer small molecules, MECOM and 17-alpha-estradiol (−7.1 kcal/mol), RCN2 and emodin (−8.3 kcal/mol), RCN2 and alpha-tocopherol (−5.6 kcal/mol), and MBNL3 and 17-beta-estradiol (−7.1 kcal/mol) were identified. Based on the DEceRNA network and Kaplan–Meier survival analysis, we identified three important ceRNA networks associated with the poor prognosis of CCA. Four anti-cancer small molecules were screened out by computer-assisted drug screening as potential small molecules for the treatment of CCA. This study provides theoretical support for the development of ceRNA network-based drugs to improve the prognosis of CCA. [ABSTRACT FROM AUTHOR]

Cell-released nanovesicles can induce anti-leukemia immunity. Leukemia cell-derived exosomes (LEXs) are promising anti-tumor vaccine components for cancer immunotherapy. Nonetheless, LEX-based vaccines show modest potency in vivo, likely due to the presence of immunosuppressive PD-L1 proteins in the exosomes. We hypothesized that targeting exosomal PD-L1 could optimize LEX-based vaccines. To test this hypothesis, we compared the capacity of exosomes derived from PD-L1-silenced acute lymphocytic leukemia-derived leukemia cells (LEXPD-L1si) and non-modified exosomes to induce anti-leukemia immunity. Lentivirus-mediated PD-L1 shRNA was used to downregulate PD-L1 expression in parental leukemia cells and LEXs. LEXPD-L1si were characterized by electron microscopy, Western blotting, nanoparticle tracking analysis and flow cytometry, and their anti-leukemia immune effects were tested on immune cells and in animal models. In the present study, lentivirus-mediated PD-L1 shRNA successfully downregulated PD-L1 expression in parental leukemia cells and in LEXs. LEXPD-L1si induced better DC maturation and subsequently enhanced T cell activation, as compared with non-modified LEXs. Consistently, immunization with LEXPD-L1si induced greater T cell proliferation and Th1 cytokine release. LEXPD-L1si was a more potent inducer of antigen-specific cytotoxic lymphocyte (CTL) response. Finally, we vaccinated DBA/2 mice with exosome formulations to test their ability to induce both protective and therapeutic anti-tumor CTL responses in vivo. Vaccination with LEXPD-L1si strongly inhibited tumor growth and prolonged survival of immunized mice. Downregulation of exosomal PD-L1 expression in LEXs effectively induces more potent anti-leukemia immunity. Therefore, our strategy for optimizing LEX-based vaccine has a potential application in leukemia immunotherapy. [ABSTRACT FROM AUTHOR]

Pr-doped M-type barium ferrite with a composition of Ba1−xPrxFe12O19 (0.00 < x < 0.25) was prepared via solid-state sintering combined with high-energy ball milling. The structures, spectra, morphologies, and magnetic properties of Pr3+-substituted Ba hexaferrites were analyzed herein. Under high-energy ball milling, the material produces crystal vacancy defects for elemental doping. The X-ray diffraction results showed that the hexagonal crystal structure was affected when the Pr content (x) was > 0.20. The GSAS refinement results show that the synthesized samples were good. The scanning electron microscopy results and Fourier transform infrared (FT-IR) spectra of the tetrahedral and octahedral sites (FT-IR result of the Fe–O bond = 601 and 448 cm−1 peaks, respectively) of the prepared material proved the formation of a hexagonal crystal structure. The magnetic properties of the samples were measured using a vibrating sample magnetometer at room temperature, and the obtained results demonstrated that the coercivity increased with an increase in the doping amount (from 3815.03 at x = 0 to 4600.56 kOe at x = 0.25). At the same time, the saturation magnetization maintained its high value (> 72.568 emu/g), which is beneficial for preparing permanent magnets. [ABSTRACT FROM AUTHOR]

Intercalation is an effective method to modify physical properties and induce novel electronic states of transition metal dichalcogenide (TMD) materials. However, it is difficult to reveal the microscopic electronic state evolution in the intercalated TMDs. Here we successfully synthesize the copper-intercalated 1T-TaS2 and characterize the structural and electronic modification combining resistivity measurements, atomic-resolution scanning transmission electron microscopy (ADF-STEM), and scanning tunneling microscopy (STM). The intercalated Cu atom is determined to be directly below the Ta atom and suppresses the commensurate charge density wave (CCDW) phase. Two specific electronic modulations are discovered in the near-commensurate (NC) CDW phase: the electron doping state near the defective star of Davids (SDs) in metallic domains and the spatial evolution of the Mott gap in insulating domains. Both modulations reveal that intercalated Cu atoms act as a medium to enhance the interaction between intralayer SDs, in addition to the general charge transfer effect. It also solidifies the Mott foundation of the insulating gap in pristine samples. The intriguing electronic evolution in Cu-intercalated 1T-TaS2 will motivate further exploration of novel electronic states in the intercalated TMD materials. [ABSTRACT FROM AUTHOR]

The electronic evolution of doped Mott insulators has been extensively studied for decades in search of exotic physical phases. The proposed Mott insulator 1T-TaS2 provides an intriguing platform to study the electronic evolution via doping. Here we apply scanning tunneling microscopy (STM) to study the evolution in Ti-doped 1T-TaS2 at different doping levels. The doping Ti atom locally perturbs the electronic and spin state inside the doped star of David and induces a clover-shaped orbital texture at low-doping levels (x < 0.01). The insulator to metal transition occurs around a critical point x = 0.01, in which small metallic and large insulating domains coexist. The clover-shaped orbital texture emerges at a broader energy range, revealing a competition with the electron correlation. It transforms to a disorder-induced Anderson insulating behavior as doping increases. We directly visualize the trapped electrons in dI/dV conductance maps. The comprehensive study of the series of Ti-doped 1T-TaS2 deepens our understanding of the electronic state evolution in a doped strong-correlated system. [ABSTRACT FROM AUTHOR]

The natural grasslands in northern China have been seriously degraded due mainly to overgrazing and climate change in recent decades, leading to shortage of forage supply to animal husbandry. To maximize forage production, we developed a two-harvest regime of oat forage by sowing in spring in an alpine region of Hulun Buir, northern China, using two oat early maturation species. The agronomic characteristics and forage quality of the two-harvest regime were evaluated across three constructive years from 2017 to 2019. Compared to the traditional one-harvest regime, the production, resource use efficiency, and economic benefits were compared and quantified for both oat species across the 3 years. Dry weight forage by the two-harvest regime was increased by 17.5–18.5%, while crude protein was increased by 25.1–30.0%. Growing days by the two-harvest regime was increased by 36.7% on average, nitrogen fertilizer use efficiency was enhanced by 25.1–30.0%, while water use efficiency was not significantly changed. The two-harvest regime also increased the net profit by 28.0%. Taken together, our results reveal that the two-harvest regime of forage production in the cold region of northern China is a promising practice with high forage yield, nutritional value, and nitrogen fertilizer use efficiency as well as economic profit. [ABSTRACT FROM AUTHOR]

Wire arc additive manufacturing based on cold metal transfer was applied to deposit 316L and Inconel 625 bimetallic structures in this work. The effect of deposition sequence on the microstructure and properties of the bimetallic structure was emphatically studied. The results showed that with the increase in the number of deposition layers, the morphology of δ-ferrite in 316L changed from lath to skeleton, and the amount of Laves phase in Inconel 625 increased. When depositing 316L first and then depositing Inconel 625 (316L-Inconel 625), the interface was well bonded with no defects. However, at the interface of the other bimetallic structure (Inconel 625-316L), plenty of Laves phases rich in Nb and Mo elements appeared, and there were two cracks propagating along the interface to the 316L and Inconel 625 deposition side, which were attributed to the diffusion of Cr and Ni elements and the Laves phase. The fracture of the 316L-Inconel 625 tensile samples occurred on the 316L side, which was a ductile fracture. The Inconel 625-316L tensile samples broke at the interface due to the cracks, which was a mixture of brittle and ductile fracture. [ABSTRACT FROM AUTHOR]

In this work, we report a 3D biomass foam absorber by uniformly loading plasmonic Au nanoparticles (Au-NPs) on carbonized rice husk porous substrate for solar vapor generation. The organic bubbles were simultaneously used as templates to construct porous channels and as carriers to introduce Au-NPs. Owing to the characteristic plasma heating effects, Au-NPs can be as additional heat spots for vapor generation to enhance the solar-thermal conversion effect at visible waves. The 3D porous absorber enables convenient water transport and high light absorption of ~ 94.6%. The solar vapor evaporation efficiency is ~ 84% in pure water and ~ 75% in 15 wt% NaCl solution under 1 kW m−2. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM2.5) has a considerable impact on the environment, climate change, and human health. Herein, we introduce a deep neural network model for deriving ground-level, hourly PM2.5 concentrations by Himawari-8 aerosol optical depth, meteorological variables, and land cover information. A total of 151,726 records were collected from 313 ground-level PM2.5 monitoring stations (spread across the North China Plain) to calibrate and test the proposed model. The sample- and site-based cross-validation yielded satisfactory performance, with correlation coefficients > 0.8 (R = 0.86 and 0.83, respectively). Furthermore, the variation in mean ground-level hourly PM2.5 concentrations, using 2017 data, showed that the proposed method could be applied for spatiotemporal continuous PM2.5 monitoring. This study will serve as a reference for the application of geostationary meteorological satellite to perform ground-level PM2.5 estimation and the utilization in atmospheric monitoring. [ABSTRACT FROM AUTHOR]

A major part of the transcriptome complexity is attributed to multiple types of DNA or RNA fusion events, which take place within a gene such as alternative splicing or between different genes such as DNA rearrangement and trans-splicing. In the present study, using the RNA deep sequencing data, we systematically survey a type of non-canonical fusions between the RNA transcripts from the two opposite DNA strands. We name the products of such fusion events cross-strand chimeric RNA (cscRNA). Hundreds to thousands of cscRNAs can be found in human normal tissues, primary cells, and cancerous cells, and in other species as well. Although cscRNAs exhibit strong tissue-specificity, our analysis identifies thousands of recurrent cscRNAs found in multiple different samples. cscRNAs are mostly originated from convergent transcriptions of the annotated genes and their anti-sense DNA. The machinery of cscRNA biogenesis is unclear, but the cross-strand junction events show some features related to RNA splicing. The present study is a comprehensive survey of the non-canonical cross-strand RNA junction events, a resource for further characterization of the originations and functions of the cscRNAs. Gene fusion, trans-splicing or transcription read-through contributes to generation of chimeric RNA. Here the authors develop a pipeline to identify non-canonical type of chimeric RNAs called cross-strand chimeric RNA (cscRNA), which are fused between two precursor RNAs transcribed from the opposite DNA strands. [ABSTRACT FROM AUTHOR]

Traditional grouting technology only provides a bonding effect to surrounding rock fissures. Here, a new expansive grout was prepared using a high-efficiency soundless crush agent as the expansion source to provide an extrusion effect in the early stage of hydration development. Expansion and uniaxial compressive strength (UCS) tests under three expansion constraint conditions were designed to analyze the expansion behavior and mechanical properties of the expansive grout. The results show that the expansion development of the grout mostly occurred within 24–72 h after final setting; greater restrictions in the constraint conditions produced a smaller volume expansion ratio and a greater compressive strength. The volume expansion ratio and UCS of expansive grout are considerable; volume expansion occurs rapidly, while the strength increases, indicating good application prospects in grouting reinforcement engineering. [ABSTRACT FROM AUTHOR]

The effect of process parameters on the forming profile of nickel-based alloy deposited by plasma and cold metal transfer (CMT) wire-arc deposition was comparatively studied. The plasma arc welding (PAW) deposition presented good wettability and high dilution rate, while CMT deposition showed the opposite. The ellipse and parabola function models for single weld bead forming profile were established by MATLAB software. The results showed that the ellipse function model had the higher similarity with the profile features of PAW and CMT deposition in terms of area error and matching degree. The single-layer multi-bead (SLMB) and single-bead multi-layer (SBML) forming profile of PAW and CMT were predicted, respectively, according to the size of wetting angle and the length of ellipse axis. There was an incomplete fusion defect at the weld toe when depositing SLMB by CMT, but not by PAW. In the SBML experiment, two sides of the PAW deposition layer were both smoother than those of the CMT deposition layer. [ABSTRACT FROM AUTHOR]

The low reproducibility is the most critical obstacle to the wide commercial application of laser-induced breakdown spectroscopy (LIBS). In this work, to improve the sample-to-sample reproducibility of LIBS real-time analysis of coal calorific value, we applied the acoustic signal generated by the laser ablation as the reference signal for normalization. First, the correlation between acoustic signal and spectral signal was analyzed and the results showed that the spectral signal from coal pellet samples with 35-ton compaction pressure had a strong correlation with acoustic signal. Second, the influences of shot-to-shot spectral intensities with different normalization methods were analyzed, including total area normalization, channel normalization, background normalization and acoustic normalization. Finally, different normalization models for calorific value were established using the support vector regression (SVR). With the acoustic normalization method, the relative standard deviation (RSD) of shot-to-shot intensities of spectral lines of C (I) 193.1 nm, C (I) 247.8 nm, H (I) 656.3 nm and N (I) 868.1 nm were significantly reduced from 10.16, 6.53, 3.79, 5.21% to 7.01, 4.40, 2.81, 3.54%, respectively. Moreover, compared with model without normalization, the average RSD of sample-to-sample measurements of validation samples based on acoustic normalization method was reduced from 6.25% to 4.16%, and the average relative error (ARE) was reduced from 4.66% to 3.28%. The results demonstrated that the acoustic normalization method can effectively reduce the fluctuations of the shot-to-shot spectral intensities and was an effective method to improve the reproducibility and accuracy of measurement of coal calorific value in LIBS. [ABSTRACT FROM AUTHOR]

Unrepaired cycle slips in carrier phase measurements will result in re-initializing integer ambiguities, during which positioning accuracy will be compromised. However, the issue of cycle slip fixing has yet to be completely solved, which impedes the realization of continuous high-precision positioning, especially in real-time precise point positioning applications. Traditional cycle slip (detection and) repair methods only use adjacent epochs to estimate cycle slips in real-time processing. Research indicates that using multiple epochs in the time-differencing model of cycle slip estimation could significantly improve cycle slip repair in real-time processing. A multi-epoch geometry-based cycle slip repair method is introduced, and it can also be implemented in real-time processing. A comparative study, including the theoretical model strength and real repairing rates for static and kinematic datasets, is performed under identical settings. The result demonstrates that a considerable number of the cycle slips unrepaired by the existing methods can be fixed by using the enhanced new method. In a low sampling rate static experiment, the average repair rates of the cycle slips unrepaired by the single-epoch geometry-based method and multi-epoch geometry-free method can be improved from 98.2% and 37.6% respectively to 99.3% by the new method using 4 epochs. In kinematic experiments, significant improvement is observed in shipborne, land-based, and airborne experiments using the new method compared with the existing methods. [ABSTRACT FROM AUTHOR]