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The measurement of mixing time in a water model of soft-stirring steelmaking ladles is practically facing a problem of bad repeatability. This uncertainty severely affects both the understandings of transport phenomenon in ladles and the measurement accuracy. Scaled down by a ratio of 1:4, a water model based on an industrial 260-ton ladle is used. This paper studies the transport process paths and mixing time of salt solution tracers in the water model of eccentric gas-stirred ladles with a low gas flow rate. After a large number of repeated experiments, the different transport paths of the tracer and the error of the mixing time in each transport path are discussed and compared with the numerical simulation results. The results of a large number of repeated experiments on the water model show that there are five transport paths for the tracer in the ladle. The tracer of the first path is mainly transported by the left-side main circulation flow, which is identical to the numerical simulation results. The tracer of the second and third paths are also mainly transported by the left-side circulation flow, but bifurcations occur when the tracer in the middle area is transported downward. In the third path, the portion and intensity of the tracer transferring to the right side from the central region is higher than in the second path. The fourth path is that the tracer is transported downward from the left, middle, and right sides with a similar intensity at the same time. While the tracer in the fifth path is mainly transported on the right side, and the tracer forms a clockwise circulation flow on the right side. The mixing times from the first transport path to the fifth transport path are 158.3 s, 149.7 s, 171.7 s, 134 s and 95.7 s, respectively, among which the third transport path and the fifth transport path are the maximum and minimum values among all transport paths. The error between the mixing time and the averaged mixing time at each monitoring point in the five transport paths of the tracer is between −34.7% and 40.9%. Furthermore, the error of the averaged mixing time of each path and the path-based average value is between 5.5% and 32.6%.

The porcine reproductive and respiratory syndrome virus (PRRSV) belongs to the Arteriviridae family and is a single-stranded, positively stranded RNA virus. The currently available PRRSV vaccines are mainly inactivated and attenuated vaccines, yet none of the commercial vaccines can provide comprehensive, long-lasting, and effective protection against PRRSV. SR717 is a pyridazine-3-carboxamide compound, which is commonly used as a non-nucleoside STING agonist with antitumor and antiviral activities. Nevertheless, there is no evidence that SR717 has any antiviral effects against PRRSV. In this study, a dose-dependent inhibitory effect of SR717 was observed against numerous strains of PRRSV using qRT-PCR, IFA, and WB methods. Furthermore, SR717 was found to stimulate the production of anti-viral molecules and trigger the activation of the signaling cascade known as the stimulator of interferon genes (STING) pathway, which contributed to hindering the reproduction of viruses by a certain margin. Collectively, these results indicate that SR717 is capable of inhibiting PRRSV infection in vitro and may have potential as an antiviral drug against PRRSV.

Interrupted-sampling repeater jamming (ISRJ) is widely used in the field of electronic countermeasures, and can severely affect radar detection. Therefore, the problem of ISRJ suppression is a compelling task. In this paper, we propose an ISRJ suppression method based on an intrapulse frequency-coded joint frequency modulation (FM) slope agile waveform. The intrapulse frequency-coded joint FM slope agile waveform is first designed. The delay inserted between subpulses makes the waveform easy to implement in engineering, and the ambiguity function diagram of the waveform approximates the ideal thumbtack type. Next, the echo slices are classified in the fractional domain utilizing the discontinuity of ISRJ and the focusing property of fractional Fourier transform for chirp signals. Then, the target and interference in the interfered echo slices are reconstructed by compressed sensing, and a time-domain filter is constructed based on interference-free echo slices. Finally, the echo signal after interference suppression is further filtered in the time domain to degrade range sidelobes. Simulation results show that the proposed method can effectively suppress three typical types of ISRJ. Moreover, the probability of target detection after interference suppression exceeds 90% when the jamming-to-signal ratio equals 50 dB.

Polar format algorithm (PFA) is a widely used high-resolution SAR imaging algorithm that can be implemented in advanced widefield staring synthetic aperture radar (WFS-SAR). However, existing algorithms have limited analysis in wavefront curvature error (WCE) and are challenging to apply to WFS-SAR with high-resolution and large-swath scenes. This paper proposes an extended polar format algorithm for joint envelope and phase error correction in WFS-SAR imaging with maneuvering trajectory. The impact of the WCE and residual acceleration error (RAE) are analyzed in detail by deriving the specific wavenumber domain signal based on the mapping relationship between the geometry space and wavenumber space. Subsequently, this paper improves the traditional WCE compensation function and introduces a new range cell migration (RCM) recalibration function for joint envelope and phase error correction. The 2D precisely focused SAR image is acquired based on the spatially variant inverse filtering in the final. Simulation experiments validate the effectiveness of the proposed method.

A multifunctional and biocompatible hybrid microgel (poly(VPBA-AAm)-CD) using N, S-doped carbon dots (CDs) and ethylene glycol dimethacrylate (EGDMA) as cross-linking agents, and 4-vinylbenzene boronic acid (VPBA) and acrylamide (AAm) as monomers, was designed in this work. This microgel can be easily prepared by a simple one-pot radical dispersion polymerization of the reactants using a rationally designed hydrogen-bonded complex method. The hybrid microgels were spherical particles with a smooth surface and an average particle size of 234 ± 8 nm. The poly(VPBA-AAm)-CD microgel displayed the glucose-responsive swelling within a clinically concerned range at a physiological pH and could realize the controllable release of insulin. In addition, the release rate of insulin in the hybrid microgel (poly(VPBA-AAm)-CD) could be triggered by glucose concentrations in the solution, and the increasing glucose concentrations can accelerate the insulin release. Further in vitro cytotoxicity studies showed that the microgel had good biocompatibility and no obvious toxicity to the cells. These indicate that the prepared microgel (poly(VPBA-AAm)-CD) may supply a new pattern for the self-regulating therapy of insulin deficiency in diabetes.

A novel hydrogel (DOP/PEI-PBA) based on the “three-component” reaction of 2-formylphenylboric acid (2-FPBA), the primary amine group of polyethyleneimine (PEI) and the cis-o-dihydroxy groups of Dioscorea opposita Thunb polysaccharide (DOP) was designed in this work. The hydrogel can be easily prepared by simply mixing the three reactants at room temperature. The hydrogel had dual responsiveness to glucose and pH, and can realize the controllable release of insulin. Moreover, the hydrogel combining insulin and DOP can inhibit the reactive oxygen species (ROS) level and malondialdehyde (MDA) content, and promote glucose consumption as well as the level of superoxide dismutase (SOD), in high-glucose-induced injury in HL-7702 cells, which reflects the synergistic effect of insulin and DOP to protect hepatocytes from oxidative stress at the same time. Further in vitro cytotoxicity studies showed that the hydrogel had good biocompatibility and no obvious toxicity to cells. These indicate that the prepared hydrogel (DOP/PEI-PBA) can be expected to be applied in the clinical treatment of insulin deficiency in diabetes.

The production of cereals, including rice, wheat, and maize has increased in China over the past 20 years. However, variations in the production and cultivated area of cereals remains unclear. In this study, we collected and analyzed the cereal production and cultivated area in China from 1998 to 2016. An 85% increase in cereal production was recorded from 1998 to 2016, due to an increase in the maize production along with the increase in the cultivated area. Meanwhile, rice and wheat production have been stable since 2000. No change occurred in the rice cultivated area through 2016, and a 19% decrease in the wheat cultivated area was observed in 2016 relative to 1998. In addition, a significant positive relationship was observed among cereal production, maize production, and cultivated area (p < 0.0001). Together, the increase in cereal production in China over the past two decades has resulted from the increase in maize cultivated area and the consequent increase in maize production.

High concentrations of heavy metals in the soil should be removed for environmental safety. Cadmium (Cd) is a heavy metal that pollutes the soil when its concentration exceeds 3.4 mg/kg. Although the potential use of cotton to remediate heavy Cd-polluted soils is known, little is understood about the molecular mechanisms of Cd tolerance. In this study, transcriptome analysis was used to identify Cd tolerance genes and their potential mechanisms in cotton. We exposed cotton plants to excess Cd and identified 4627 differentially expressed genes (DEGs) in the root, 3022 DEGs in the stem and 3854 DEGs in the leaves through RNA-Seq analysis. Among these genes were heavy metal transporter coding genes (ABC, CDF, HMA, etc.), annexin genes and heat shock genes (HSP), amongst others. Gene ontology (GO) analysis showed that the DEGs were mainly involved in the oxidation–reduction process and metal ion binding. The DEGs were mainly enriched in two pathways, the influenza A and pyruvate pathway. GhHMAD5, a protein containing a heavy-metal binding domain, was identified in the pathway to transport or to detoxify heavy metal ions. We constructed a GhHMAD5 overexpression system in Arabidopsis thaliana that showed longer roots compared to control plants. GhHMAD5-silenced cotton plants showed more sensitivity to Cd stress. The results indicate that GhHMAD5 is involved in Cd tolerance, which gives a preliminary understanding of the Cd tolerance mechanism in upland cotton. Overall, this study provides valuable information for the use of cotton to remediate soils polluted with Cd and potentially other heavy metals.