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The identification of herbicide tolerance is essential for effective chemical weed control. According to whole-plant dose–response assays, none of 29 pond lovegrass [Eragrostis japonica (Thunb.) Trin.] populations were sensitive to penoxsulam. The effective dose values of penoxsulam causing 50% inhibition of fresh weight (GR50: 105.14 to 148.78 g ai ha−1) in E. japonica populations were much higher than the label rate of penoxsulam (15 to 30 g ai ha−1) in the field. This confirmed that E. japonica was tolerant to penoxsulam. Eragrostis japonica populations showed 52.83- to 74.76-fold higher tolerance to penoxsulam than susceptible barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.]. The mechanisms of tolerance to penoxsulam in E. japonica were also identified. In vitro activity assays revealed that the penoxsulam concentration required to inhibit 50% of the acetolactate synthase (ALS) activity (IC50) was 12.27-fold higher in E. japonica than in E. crus-galli. However, differences in the ALS gene, previously found to endow target-site resistance in weeds, were not detected in the sequences obtained. Additionally, the expression level of genes encoding ALS in E. japonica was approximately 2-fold higher than in E. crus-galli after penoxsulam treatment. Furthermore, penoxsulam tolerance can be significantly reversed by three cytochrome P450 monooxygenase (CytP450) inhibitors (1-aminobenzotriazole, piperonyl butoxide, and malathion), and the activity of NADPH-dependent cytochrome P450 reductase toward penoxsulam in E. japonica increased significantly (approximately 7-fold higher) compared with that of treated E. crus-galli. Taken together, these results indicate that lower ALS sensitivity, relatively higher ALS expression levels, and stronger metabolism of CytP450s combined to bring about penoxsulam tolerance in E. japonica.

With the commercialization of the fifth-generation mobile communication network (5G), the scale of the unmanned aerial vehicle (UAV) industry has continued to expand. However, the unregistered UAV has caused frequent harassment incidents at international airports, and the problem of UAV crimes is increasing. Radio technology supports long-distance detection of unregistered UAV and can be used as an efficient early warning method for unregistered UAV, which has attracted extensive attention from academia and industry. The classic UAV detection based on remote control signal method faces technical bottlenecks such as being easily affected by environmental noise, high complexity, and low detection accuracy. In the paper, an UAV remote control signal detection method is proposed based on cyclic spectrum features. More specifically, a dataset of UAV remote control signal UAV-CYCset is firstly constructed in the frequency domain. Based on UAV-CYCset dataset, a network architecture is proposed based on improved AlexNet, and the average detection accuracy of the improved model reaches 85% (from -10 dB to 10 dB) according to the simulation experiments.

Developing new electrode materials with a high specific capacity for excellent lithium-ion storage properties is very desirable. The MnCO3/Mn3O4 nanoparticles with uniform size (about 50 nm) and shape which are wrapped with graphene have been successfully synthesized via the one-step method for anode material of lithium-ion batteries. The as-prepared graphene-wrapped MnCO3/Mn3O4 nanocomposite exhibits remarkable electrochemical performance, including high reversible specific capacity, outstanding cycling stability, and excellent rate capability in comparison with the bare MnCO3 and MnCO3/Mn3O4 nanocomposite. This is because the synergistic effect of MnCO3 and Mn3O4 nanoparticles and graphene nanosheets act as both electron conductors and volume buffer layers. From the scanning electron microscopy (SEM) analysis, we confirmed that the morphology and structure of the composite are preserved after 200 cycles. This further confirms that graphene-wrapped MnCO3/Mn3O4 nanocomposite acts as a stable template for reversible lithium-ion intercalation/deintercalation.

Cu/Al clad sheets with a 304 stainless steel foil (SUS304) interlayer are successfully fabricated by the powder-in-tube method. The influence of SUS304 thickness on the interfacial structure, elemental diffusion, and peeling strength of the clad sheets is studied. Experimental results indicate that the initial Cu/Al interface is partially transformed into a Cu/SUS304/Al interface after introducing the SUS304 interlayer. The proportion of SUS304 fragments at the bonding interface is shown to increase with thickness of the SUS304 interlayer. Differences in deformability between SUS304 interlayer and Cu/Al matrix promote the occurrence of shear deformation at the bonding interface via the cladding process, enhancing atomic diffusion at the Cu/SUS304/Al interface. Peeling tests reveal that interfacial cracks in clad sheets with an SUS304 interlayer propagate along the Cu/SUS304 and Cu/Al interfaces. Under combined effects of interfacial transfer and large shear strain, the interfacial strength of clad sheets is apparently improved. Clad sheets with the thickest SUS304 interlayer (30 μm) exhibit highest peeling strength (30.9 N/mm), demonstrating 73.6% improvement over clad sheets without an interlayer. These findings provide novel insights into the innovative design of clad sheets possessing extraordinary interfacial strength.

Determining atomic structure of intercalated metallic layer under graphene is a hot-topic due to the potential applications in electronic engineering. In this study, Pb-intercalated graphene (PbG) is fabricated on SiC substrate and the atomic structure and electronic properties of the intercalated Pb atoms underneath graphene are investigated by scanning tunneling microscopy/spectroscopy (STM/STS). As the crystal facet of intercalated Pb atoms can be arranged in (111) (unit cell, 0.35 nm × 0.35 nm) and (110) (unit cell, 0.61 nm × 0.35 nm), mottled moire pattern (period, 2.5 nm) and striated moire pattern (period, 2.1 nm) are formed. Atomic arrangement of the intercalated Pb is sensitive to tip scanning resulting in the conversion of the two moire patterns. Nevertheless, the crystal orientation of moire patterns is always aligned with zigzag direction of graphene. As revealed by STS, PbG performs the similar electronic states to those of free-standing graphene due to the shielding effects of Pb intercalation. The crystallographic relationship between graphene and Pb atoms is also confirmed by density functional theory (DFT) calculations. The study provides crucial for understanding the structure of intercalated Pb atoms underneath a graphene layer, which may enable the development of new 2D materials capped by graphene.

Nasal bone fracture is the most common injury in the craniofacial area. Understanding the etiology of nasal bone fracture is important for the development of preventive public health programs. In this study, the authors retrospectively examined medical records to extract information about sex, age, injury time, injury cause, occupation, and place of residence (urban or rural) from 1441 patients with nasal bone fracture to investigate the etiology of nasal bone fracture in China. Among the 1441 patients, the ratio of males to females was 3.4:1. The mean patient age was 29.25 years. The most common occupation was student (31.02%). Violence was the most common cause of injury in male patients (35.82%), whereas slip-and-fall accidents were the most common cause in female patients (32.11%). Violence was the most common cause of injury in both urban and rural patients, and 74.19% were attacked by others without a weapon. This report provides important data about the etiology of nasal bone fracture in China and will help improve nasal bone fracture prevention measures.

Pond lovegrass [Eragrostis japonica (Thunb.) Trin.] is an annual grass weed of rice fields worldwide. Cyhalofop-butyl has been widely used for controlling annual grass weeds in rice fields. However, E. japonica is tolerant to cyhalofop-butyl. The effective dose values of cyhalofop-butyl for 29 E. japonica populations causing 50% inhibition of fresh weight (GR

High-entropy alloys exhibit great potential for cryogenic applications. This study investigates the nano-scratching behavior of CuCoCrFeNi high-entropy alloy at a cryogenic temperature (77 K) using molecular dynamics. Results show that compared with the single-grain model, the average friction coefficient (AFC) increases for all three polycrystalline models with different grain sizes d, but the anti-wear property can be improved by 28.5%, when grain size d = 10.7 nm. The smaller friction on the scratching surface of the single-grain model (AFC is 15.5% less than that of the model with d = 8.2 nm), which makes the overall temperature rise lower compared to that of the polycrystalline models. However, due to the stress concentration released when a complete stacking fault tetrahedron is produced, the single-grain model cannot significantly harden the surface and subsurface to a greater degree. In the polycrystalline models, dislocations are blocked at grain boundaries (GBs). However, the introduction of GBs changes the von Mises stress distribution. Finally, an attempt was made to reveal the role of yield pressure H3/ E2 ( H—hardness, E—elastic modulus) in friction-reducing and anti-wear properties.

Summary Heat stress (HS) causes substantial damages to worldwide crop production. As a cool season crop, wheat (Triticum aestivum) is sensitive to HS‐induced damages. To support the genetic improvement of wheat HS tolerance (HST), we conducted fine mapping of TaHST1, a locus required for maintaining wheat vegetative and reproductive growth under elevated temperatures. TaHST1 was mapped to the distal terminus of 4AL chromosome arm using genetic populations derived from two BC6F6 breeding lines showing tolerance (E6015‐4T) or sensitivity (E6015‐3S) to HS. The 4AL region carrying TaHST1 locus was approximately 0.949 Mbp and contained the last 19 high confidence genes of 4AL according to wheat reference genome sequence. Resequencing of E6015‐3S and E6015‐4T and haplotype analysis of 3087 worldwide wheat accessions revealed heightened deletion polymorphisms in the distal 0.949 Mbp region of 4AL, which was confirmed by the finding of frequent gene losses in this region in eight genome‐sequenced hexaploid wheat cultivars. The great majority (86.36%) of the 3087 lines displayed different degrees of nucleotide sequence deletions, with only 13.64% of them resembling E6015‐4T in this region. These deletions can impair the presence and/or function of TaHST1 and surrounding genes, thus rendering global wheat germplasm vulnerable to HS or other environmental adversities. Therefore, conscientious and urgent efforts are needed in global wheat breeding programmes to optimize the structure and function of 4AL distal terminus by ensuring the presence of TaHST1 and surrounding genes. The new information reported here will help to accelerate the ongoing global efforts in improving wheat HST.

Background Recent data suggest that complications and death from coronavirus disease 2019 (Covid-19) may be related to high viral loads. Methods In this ongoing, double-blind, phase 1–3 trial involving nonhospitalized patients with Covid-19, we investigated two fully human, neutralizing monoclonal antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, used in a combined cocktail (REGN-COV2) to reduce the risk of the emergence of treatment-resistant mutant virus. Patients were randomly assigned (1:1:1) to receive placebo, 2.4 g of REGN-COV2, or 8.0 g of REGN-COV2 and were prospectively characterized at baseline for endogenous immune response against SARS-CoV-2 (serum antibody–positive or serum antibody–negative). Key end points included the time-weighted average change in viral load from baseline (day 1) through day 7 and the percentage of patients with at least one Covid-19–related medically attended visit through day 29. Safety was assessed in all patients. Results Data from 275 patients are reported. The least-squares mean difference (combined REGN-COV2 dose groups vs. placebo group) in the time-weighted average change in viral load from day 1 through day 7 was −0.56 log10 copies per milliliter (95% confidence interval [CI], −1.02 to −0.11) among patients who were serum antibody–negative at baseline and −0.41 log10 copies per milliliter (95% CI, −0.71 to −0.10) in the overall trial population. In the overall trial population, 6% of the patients in the placebo group and 3% of the patients in the combined REGN-COV2 dose groups reported at least one medically attended visit; among patients who were serum antibody–negative at baseline, the corresponding percentages were 15% and 6% (difference, −9 percentage points; 95% CI, −29 to 11). The percentages of patients with hypersensitivity reactions, infusion-related reactions, and other adverse events were similar in the combined REGN-COV2 dose groups and the placebo group. Conclusions In this interim analysis, the REGN-COV2 antibody cocktail reduced viral load, with a greater effect in patients whose immune response had not yet been initiated or who had a high viral load at baseline. Safety outcomes were similar in the combined REGN-COV2 dose groups and the placebo group. (Funded by Regeneron Pharmaceuticals and the Biomedical and Advanced Research and Development Authority of the Department of Health and Human Services; ClinicalTrials.gov number, NCT04425629.)

In this paper, an implementation method of high sensitivity thin film fiber optic pressure sensor based on air blowing method is proposed. The utility model is characterized in that a film ultra-thin microbubble structure is firstly formed on the surface of the AB epoxy glue solution by using high-pressure air, and then the film portion of the end portion of the microbubble is transferred to a single-mode fiber head with a hollow glass tube at the top. Finally, a thin film structure fiber Fabry-Perot fiber pressure sensor is formed. The experimental results show that the thickness of the thin film layer at the end of the FP sensor is only 16 μm. Correspondingly, the maximum pressure sensitivity can reach 263.15 pm/kPa. Meanwhile, due to the decrease of film thickness, the sensor's resistance to temperature interference is improved. The prepared fiber Fabry-Perot pressure sensor has the advantages of ultra-thin film thickness, high-pressure sensitivity, low cost and good repeatability. Therefore, it has good application value in high sensitivity pressure and sound wave detection.

A compact and robust Fabry-Perot interferometer (FPI) based on polymer core is proposed and experimentally demonstrated. The fabrication is low-cost and has simple processes, including fusion splicing and polymer injection. Its characteristic is that the polymer fills the entire capillary core, which is easy to demodulate, and provides a good platform for the refractive index measurement of the polymer after curing. The experimental result shows a linear temperature sensitivity of 1226.64 pm/°C between 39°C and 54°C. Furthermore, we also used the Vernier effect to improve the temperature sensitivity as high as −15.617 nm/°C. The proposed FPI structure provides potential application in the research of sensors and polymer optical fibers.

The resistance of weeds to herbicides poses a major threat to agricultural production, and non-target-site resistance (NTSR) is often a serious problem as its mechanisms can in some cases confer resistance to herbicides with different modes of action. In this study, we hypothesized that bZIP transcription factors (TFs), which regulate abiotic stress responses in many plants, play a regulatory role in NTSR. Whole-plant assays indicated that the wild grasses Echinochloa crus-galli and E. glabrescens are resistant to the herbicides penoxsulam, cyhalofop-butyl, and quintrione. Transcriptome sequencing then identified 101 and 49 bZIP TFs with differential expression following penoxsulam treatment in E. crus-galli and E. glabrescens, respectively. Twelve of these genes had >60% homology with rice genes. The expression of bZIP88 was considerably up-regulated 6 h after treatment with the three different herbicides, and it was similar between resistant and susceptible populations; however, the relative expression levels before herbicide treatment and 24 h after were the same. We used rice (Oryza sativa ssp. japonica cv Nipponbare) as a model system for functional validation and found that CRISPR-Cas9-knockout of the rice bZIP88 ortholog increased the sensitivity to herbicide, whereas overexpression reduced it. The OsbZIP88 protein was localized to the nucleus. Using ChIP coupled with high-throughput sequencing, OsbZIP88 was found to form a network regulatory center with other TFs such as bZIP20/52/59 to regulate OsKS1, OsCOE1, and OsIM1, which are related to auxin, abscisic acid, brassinosteroids, and gibberellic acid. Based on these results, we have established a database of bZIP TFs corresponding to herbicide stress, and resolved the mechanisms of the positive regulation of herbicide resistance by bZIP88, thereby providing new insights for NTSR.

Zusammenfassung Herkömmliche Pellistoren auf der Basis von porösen Al2O3 als Trägermaterial für einen Pd-Katalysator benötigen eine Arbeitstemperatur von rund 450 °C für den Nachweis von Methan. Durch diese hohe Temperatur sind sie anfällig für „Vergiftungen“ durch Silizium-haltige Gase. Eine gute Alternative bieten Co3O4-basierte Träger in Kombination mit bimetallischen katalytischen Nanomaterialien, mit denen die Arbeitstemperatur auf rund 300 °C gesenkt werden kann. Wir stellen in diesem Beitrag unsere Ergebnisse für ein Materialsystem aus mesoporösem Co3O4 mit Au-Pd-Funktionalisierung vor. Die erzielten Ergebnisse zeigen, dass mesoporöses Co3O4 vorteilhaft gegenüber kommerziell erhältlichem polykristallinem Co3O4 in Bezug auf die katalytische Umsetzung ist. Zudem beeinflusst der Bedeckungsgrad des Co3O4 mit Au-Pd-Partikeln das katalytische Verhalten des Sensors. Die niedrigere Betriebstemperatur des untersuchten Materialsystems verbessert den Explosionsschutz entscheidend und senkt die Heizleistungsaufnahme. Bei den für die Experimente verwendeten Substraten verringert sich die Heizleistungsaufnahme von 610 mW bei 450 °C auf 355 mW bei 300 °C Arbeitstemperatur.

It is important to control exoskeleton to act synchronously with the user for movement assistance. A knee exoskeleton was constructed for gait rehabilitation training, and a control method based on adaptive frequency oscillator (AFO) was presented for swing motion of knee exoskeleton. Firstly, during the learning mode, the user flexed and extended with the exoskeleton leg together, and the exoskeleton leg was not actuated. The phase of the exoskeleton angle extracted, and the envelope curve of the user’s EMG is generated based on AFO. Then, during power-assisted mode, the assistive torque is generated according to the angle phase on-line and the restructuring muscle torque. At last, the assistive torque as a feedback signal was input to the admittance model for the swing control of the knee exoskeleton. The experiments of swing control showed that knee exoskeleton can follow the user’s motion well.

Herein, we have designed and synthesized a series of MnOx/g-C3N4 composite photocatalysts via a one-step heat treatment method using a mixture of melamine and manganese acetate precursors. The as-prepared MnOx/g-C3N4 composite photocatalysts show high photocatalytic H2 production activity, and an optimal loading of 1.8[Formula: see text]wt.% MnOx can enhance the H2 production by approximately 2.7 times than that with pure g-C3N4. The high photocatalytic H2-production activity can be attributed to the hole trapping and absorbing ability of the MnOx cocatalyst, which can significantly inhibit the recombination rate of the photogenerated electrons and holes. This work not only shows a simple way to enhance the photocatalytic H2-production activity of g-C3N4 but also demonstrates that MnOx can be used as an efficient and low-cost cocatalyst for the photocatalytic production of H2.

Sn-58Bi-0.1Er solder alloys with different Ni-CNTs contents were prepared by vacuum melting, the influence of Ni-CNTs content on the wetting properties of Sn-58Bi-0.1Er solder was studied. The interface morphology of IMC at Sn-58Bi-0.1Er/Cu joint and the creep resistance of Sn-58Bi-0.1Er/Cu joints with different contents of Ni-CNTs were analyzed. The results showed that when added 0.01~0.05 wt% Ni-CNTs, it enhanced the wettability of composite solder alloy on Cu plate, and the inter metallic compound of Sn58Bi/Cu interface changed from sawtooth Cu6Sn5 to thin layer (Cu, Ni)6Sn5. With the increase amount of Ni-CNTs enhanced particles, it can effectively reduce the thickness of IMC layer at the Sn58Bi-0.1Er/Cu interface. By adding Ni-CNTs particles, the creep fracture life of Sn58Bi-0.1Er/Cu joints was greatly improved. The creep fracture life of the joint was the longest when 0.03 wt%Ni-CNTsadded, which was 25650s. The addition of Ni-CNTs reinforcement particles effectively improved the mechanical properties of the Sn58Bi joint.

The optical Vernier effect is a powerful tool for improving the sensitivity of an optical sensor, which relies on the use of two sensor units with slightly detuned frequencies. However, an improper amount of detuning can easily cause the Vernier effect to be unusable. In this work, the effective generation range of the Vernier effect and the corresponding interferometer configuration are suggested and experimentally demonstrated through a tunable cascaded Fabry–Perot interferometer structure. We further demonstrate a practical method to increase the magnification factor of the Vernier effect based on the device bandwidth. Only the optical path length of an interferometer probe and the sensitivity of the measurement parameters are needed to design this practical interferometer based on the Vernier effect. Our results provide potential insights for the sensing applications of the Vernier effect.

The 6063 Aluminum alloy brazing joint was prepared with the Al-Si12 solder. The effect of welding time on the structure and shear properties of brazing weld is studied and the interface is analyzed. The study shows that the spreading performance of brder gradually increases with the welding time, the shear strength of the 6063 aluminum alloy joint increase first and then decreases with the increase of the welding time. When the optimal brazing process is 605°C 15min, the interface between Al-Si12 solder and aluminum alloy is good, and the shear strength is 122.4MPa. To ensure the bonding strength of 6063 aluminum alloy, the optimal insulation time of brazing is 15min.

The signal-to-noise ratio (SNR) is an effective evaluation index for channel status and communication quality, and plays an important role in signal analysis. Under the gradual complexity of the unmanned aerial vehicle (UAV) remote control signal environment and the rapid development of neural network models in deep learning, this paper proposes a convolutional neural network (CNN) model-based SNR estimation method of UAV remote control signal environment. We construct a simulation dataset of UAV remote control signal with different SNRs, then train the model and its parameters, save the model with better performance and use the test set to verify the performance of the algorithm finally. The experimental result shows that the performance of the algorithm is improved compared to the two known algorithm.

In this paper, an Unmanned Aerial Vehicles (UAV) control signal detection scheme is proposed with Convolutional Neural Network (CNN). More specifically, the sampled signal images of UAV control signal are considered to train the classical LeNet network under various signal-to-noise ratios (SNR). The simulation experiments state that the detection performance of UAV control signal is greatly improved. In addition, the conclusion is drawn that the increase in signal image size helps to improve the detection performance.

BackgroundContinued SARS-CoV-2 infections and COVID-19-related hospitalizations highlight the need for effective anti-viral treatments in the outpatient setting. In a descriptive interim analysis of the phase 1/2 portion of a double-blind phase 1/2/3 trial in COVID-19 outpatients conducted between June 16, 2020 and September 4, 2020, REGEN-COV® (casirivimab plus imdevimab) antibody combination reduced SARS-CoV-2 viral load versus placebo.MethodsThis final phase 1/2 analysis comprises 799 outpatients, including 275 from the previous descriptive analysis (group-1) and 524 from phase 2 (group-2). Patients were randomized (1:1:1) to placebo, REGEN-COV 2400mg, or REGEN-COV 8000mg. Prespecified hierarchical analyses of virologic endpoints were performed in group-2. The proportion of patients with ≥1 COVID-19–related medically attended visit (MAV) through day 29 was assessed in group-1+2. Efficacy was assessed in patients confirmed SARS-CoV-2–positive by baseline nasopharyngeal RT-qPCR. Safety was assessed in all treated patients.ResultsData from 799 outpatients enrolled from June 16, 2020 to September 23, 2020 are reported. Time-weighted average daily reduction in viral load through day 7 was significantly greater in the REGEN-COV combined 2400mg+8000mg group versus placebo in patients with baseline viral load >107 copies/mL (prespecified primary endpoint): -0.68 log10 copies/ml (95% CI, -0.94 to -0.41; PPP=.0003) log10 copies/mL in serum antibody–negative patients and in the overall population, respectively. REGEN-COV reduced the proportion of patients with ≥1 COVID-19–related MAV versus placebo (2.8% [12/434] REGEN-COV combined dose group versus 6.5% [15/231] placebo; P=.024; relative risk reduction [RRR]=57%); in patients with ≥1 risk factor for hospitalization, the treatment effect was more pronounced (RRR=71%). Adverse events were similar across groups.ConclusionsIn COVID-19 outpatients enrolled prior to the widespread circulation of delta and omicron variants, treatment with REGEN-COV significantly reduced viral load and COVID-19–related MAVs.