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In order to further improve the identification efficiency of tobacco mildew, a rapid identification model of tobacco mildew based on random forest algorithm was proposed in this study. In order to ensure the feasibility and pertinence of the model study, this study takes redried leaf tobacco as the research object, selects high-temperature and high-humidity environment as the experimental conditions, and obtains the sample data of the degree of tobacco mildew under different experimental conditions. At the same time, this paper constructs a rapid identification model of tobacco mildew with the help of random forest algorithm. Through the model experimental results, it is found that the accuracy of the model for the rapid identification of training samples can reach 93.82%, while the accuracy of independent testing is 94.84%. The experimental results fully reflect the availability and efficiency of the random forest algorithm model in the rapid identification of tobacco mildew.

Nanolattices exhibit attractive mechanical, energy conversion and optical properties, but it is challenging to fabricate large nanolattices while maintaining the dense regular nanometre features that enable their properties. Here we report a crack-free self-assembly approach for fabricating centimetre-scale nickel nanolattices with much larger crack-free areas than prior self-assembled nanolattices and many more unit cells than three-dimensionally printed nanolattices. These nickel nanolattices have a feature size of 100 nm, a grain size of 30 nm and a tensile strength of 260 MPa, which approaches the theoretical strength limit for porous nickel. The self-assembly method and porous metal mechanics reported in this work may advance the fabrication and applications of high-strength multifunctional porous materials.

The coordinated utilization of nitrogen (N) and phosphorus (P) is vital for plants to maintain nutrient balance and achieve optimal growth. Previously, we revealed a mechanism by which nitrate induces genes for phosphate utilization; this mechanism depends on NRT1.1B-facilitated degradation of cytoplasmic SPX4, which in turn promotes cytoplasmic-nuclear shuttling of PHR2, the central transcription factor of phosphate signaling, and triggers the nitrate-induced phosphate response (NIPR) and N-P coordinated utilization in rice. In this study, we unveiled a fine-tuning mechanism of NIPR in the nucleus regulated by Highly Induced by Nitrate Gene 1 (HINGE1, also known as RLI1), a MYB-transcription factor closely related to PHR2. RLI1/HINGE1, which is transcriptionally activated by PHR2 under nitrate induction, can directly activate the expression of phosphate starvation-induced genes. More importantly, RLI1/HINGE1 competes with PHR2 for binding to its repressor proteins in the nucleus (SPX proteins), and consequently releases PHR2 to further enhance phosphate response. Therefore, RLI1/HINGE1 amplifies the phosphate response in the nucleus downstream of the cytoplasmic SPX4-PHR2 cascade, thereby enabling fine-tuning of N-P balance when nitrate supply is sufficient.

The intensive application of inorganic nitrogen underlies marked increases in crop production, but imposes detrimental effects on ecosystems1,2: it is therefore crucial for future sustainable agriculture to improve the nitrogen-use efficiency of crop plants. Here we report the genetic basis of nitrogen-use efficiency associated with adaptation to local soils in rice (Oryza sativa L.). Using a panel of diverse rice germplasm collected from different ecogeographical regions, we performed a genome-wide association study on the tillering response to nitrogen-the trait that is most closely correlated with nitrogen-use efficiency in rice-and identified OsTCP19 as a modulator of this tillering response through its transcriptional response to nitrogen and its targeting to the tiller-promoting gene DWARF AND LOW-TILLERING (DLT)3,4. A 29-bp insertion and/or deletion in the OsTCP19 promoter confers a differential transcriptional response and variation in the tillering response to nitrogen among rice varieties. The allele of OsTCP19 associated with a high tillering response to nitrogen is prevalent in wild rice populations, but has largely been lost in modern cultivars: this loss correlates with increased local soil nitrogen content, which suggests that it might have contributed to geographical adaptation in rice. Introgression of the allele associated with a high tillering response into modern rice cultivars boosts grain yield and nitrogen-use efficiency under low or moderate levels of nitrogen, which demonstrates substantial potential for rice breeding and the amelioration of negative environment effects by reducing the application of nitrogen to crops.

Ptychographic X-ray computed tomography is a quantitative three-dimensional imaging technique offered to users of multiple synchrotron radiation sources. Its dependence on the coherent fraction of the available X-ray beam makes it perfectly suited to diffraction-limited storage rings. Although MAX IV is the first, and so far only, operating fourth-generation synchrotron light source, none of its experimental stations is currently set up to offer this technique to its users. The first ptychographic X-ray computed tomography experiment has therefore been performed on the NanoMAX beamline. From the results, information was gained about the current limitations of the experimental setup and where attention should be focused for improvement. The extracted parameters in terms of scanning speed, size of the imaged volume and achieved resolutions should provide a baseline for future users designing nano-tomography experiments on the NanoMAX beamline.

Pigs are considered as important hosts or “mixing vessels” for the generation of pandemic influenza viruses. Systematic surveillance of influenza viruses in pigs is essential for early warning and preparedness for the next potential pandemic. Here, we report on an influenza virus surveillance of pigs from 2011 to 2018 in China, and identify a recently emerged genotype 4 (G4) reassortant Eurasian avian-like (EA) H1N1 virus, which bears 2009 pandemic (pdm/09) and triple-reassortant (TR)-derived internal genes and has been predominant in swine populations since 2016. Similar to pdm/09 virus, G4 viruses bind to human-type receptors, produce much higher progeny virus in human airway epithelial cells, and show efficient infectivity and aerosol transmission in ferrets. Moreover, low antigenic cross-reactivity of human influenza vaccine strains with G4 reassortant EA H1N1 virus indicates that preexisting population immunity does not provide protection against G4 viruses. Further serological surveillance among occupational exposure population showed that 10.4% (35/338) of swine workers were positive for G4 EA H1N1 virus, especially for participants 18 y to 35 y old, who had 20.5% (9/44) seropositive rates, indicating that the predominant G4 EA H1N1 virus has acquired increased human infectivity. Such infectivity greatly enhances the opportunity for virus adaptation in humans and raises concerns for the possible generation of pandemic viruses.

Eighteen novel N-2,4-dimethoxyphenyl dithiolopyrrolone derivatives inhibiting bacterial RNA polymerase (RNAP) were synthesized based on dithiolopyrrolone scaffold. Some compounds displayed potent antimicrobial activity against Gram-positive bacteria of Staphylococcus aureus and Streptococcus pneumoniae, but not the Gram-negative bacteria of Escherichia coli and Pseudomonas aeruginosa. Moreover, the most promising compound 7b showed potent antibacterial activity against clinical isolates of MRSA, VRSA, RRSA, and MPRSP with MIC values in the range of 0.125–2 μg/mL, and potent inhibitory activity against Escherichia coli RNAP with IC50 value of 19.4 ± 1.3 μM. In addition, compound 7b showed cytotoxicity against LO2 cells with IC50 value of 18.5 ± 1.89 μM. Molecular docking studies revealed that compound 7b interacted with the switch region of the bacterial RNAP. Taken together, compound 7b might serve as a lead structure for developing potent bacterial RNAP inhibitors.

Converting solar energy into clean and sustainable chemical fuels is a promising strategy for exploiting renewable energy. The application of photocatalytic water splitting technology in hydrogen production is important for sustainable energy development and environmental protection. In this study, for the first time, 2D Cu7S4 co-catalysts were coupled on the surface of a CdS nanosheet photocatalyst by a one-step ultrasonic-assisted electrostatic self-assembly method at room temperature. The as-fabricated 2D–2D CdS/Cu7S4 layered heterojunctions were demonstrated to be advanced composite photocatalysts that enhance the water splitting efficiency toward hydrogen production. The highest hydrogen evolution rate of the 2D–2D CdS/2%Cu7S4 binary heterojunction photocatalyst was up to 27.8 mmol g−1 h−1 under visible light irradiation, with an apparent quantum efficiency of 14.7% at 420 nm, which was almost 10.69 times and 2.65 times higher than those of pure CdS nanosheets (2.6 mmol g−1 h−1) and CdS-2%CuS (10.5 mmol g−1 h−1), respectively. The establishment of the CdS/Cu7S4 binary-layered heterojunction could not only enhance the separation of photogenerated electron–hole (e−–h+) pairs, improve the transfer of photo-excited electrons, and prolong the life-span of photo-generated electrons, but also enhance the light absorption and hydrogen-evolution kinetics. All these factors are important for the enhancement of the photocatalytic activity. Expectedly, the 2D–2D interface coupling strategy based on CdS NSs can be extensively exploited to improve the hydrogen-evolution activity over various kinds of conventional semiconductor NSs.

For influenza A viruses (IAVs), non-structural protein 1 (NS1) protein was recognized to be the key factor to enhance virulence by antagonizing host innate anti-viral responses. However, for the pathways allowing NS1 to regulate the type I interferon (IFN) response, the identification of the substrates was still incomplete. Here a recombinant IAV encoding a NS1 containing an affinity tag (NS1-Strep) was generated to capture the NS1-interactome in the lungs of infected mice. Several scaffold proteins of the 14-3-3 family were distinguished as the most potent candidates. Based on the conserved motif RxxTxxT of NS1, the interaction between NS1 and 14-3-3ε was enabled, which competed for the binding of RIG-I to 14-3-3ε and prevented RIG-I translocation to the adaptor MAVS, consequently inhibiting IFN-β expression. A recombinant mutant IAV deficient in 14-3-3ε binding elicited a markable innate immune responses and showed impaired growth kinetics.

Many cellular genes and networks induced in human lung epithelial cells infected with the influenza virus remain uncharacterized. Here, we find that p21 levels are elevated in response to influenza A virus (IAV) infection, which is independent of p53. Silencing, pharmacological inhibition or deletion of p21 promotes virus replication in vitro and in vivo, indicating that p21 is an influenza restriction factor. Mechanistically, p21 binds to the C-terminus of IAV polymerase subunit PA and competes with PB1 to limit IAV polymerase activity. Besides, p21 promotes IRF3 activation by blocking K48-linked ubiquitination degradation of HO-1 to enhance type I interferons expression. Furthermore, a synthetic p21 peptide (amino acids 36 to 43) significantly inhibits IAV replication in vitro and in vivo. Collectively, our findings reveal that p21 restricts IAV by perturbing the viral polymerase complex and activating the host innate immune response, which may aid the design of desperately needed new antiviral therapeutics.

H5N6 highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4 not only exhibits unprecedented intercontinental spread in poultry, but can also cause serious infection in humans, posing a public health threat. Phylogenetic analyses show that 40% (8/20) of H5N6 viruses that infected humans carried H9N2 virus-derived internal genes. However, the precise contribution of H9N2 virus-derived internal genes to H5N6 virus infection in humans is unclear. Here, we report on the functional contribution of the H9N2 virus-derived matrix protein 1 (M1) to enhanced H5N6 virus replication capacity in mammalian cells. Unlike H5N1 virus-derived M1 protein, H9N2 virus-derived M1 protein showed high binding affinity for H5N6 hemagglutinin (HA) protein and increased viral progeny particle release in different mammalian cell lines. Human host factor, G protein subunit beta 1 (GNB1), exhibited strong binding to H9N2 virus-derived M1 protein to facilitate M1 transport to budding sites at the cell membrane. GNB1 knockdown inhibited the interaction between H9N2 virus-derived M1 and HA protein, and reduced influenza virus-like particles (VLPs) release. Our findings indicate that H9N2 virus-derived M1 protein promotes avian H5N6 influenza virus release from mammalian, in particular human cells, which could be a major viral factor for H5N6 virus cross-species infection., Author summary H9N2 avian influenza viruses (AIVs), through reassortment of their internal genes with other circulating AIVs subtypes (H5N6, H7N9, H10N8 and H10N3 viruses), are known to enable the resulting novel reassortants to infect humans. However, the precise roles of H9N2 virus-derived internal genes in human infection remain unknown. Here, we found that H9N2 virus-derived (but not H5N1 virus-derived) M1 protein showed strong interaction with host GNB1 protein to enhance M1 protein transport to budding sites at the cell membrane to promote progeny virus release, hence facilitating H5N6 reassortants to infect human cells.

Background Large bone defects have always been a great challenge for orthopedic surgeons. The use of a good bone substitute obtained by bone tissue engineering (BTE) may be an effective treatment method. Artificial hydroxyapatite, a commonly used bone defect filler, is the main inorganic component of bones. Because of its high brittleness, fragility, and lack of osteogenic active elements, its application is limited. Therefore, its fragility should be reduced, its osteogenic activity should be improved, and a more suitable scaffold should be constructed. Methods In this study, a microhydroxyapatite whisker (mHAw) was developed, which was doped with the essential trace active elements Mg2+ and Sr2+ through a low-temperature sintering technique. After being formulated into a slurry, a bionic porous scaffold was manufactured by extrusion molding and freeze drying, and then SiO2 was used to improve the mechanical properties of the scaffold. The hydrophilicity, pore size, surface morphology, surface roughness, mechanical properties, and release rate of the osteogenic elements of the prepared scaffold were detected and analyzed. In in vitro experiments, Sprague–Dawley (SD) rat bone marrow mesenchymal stem cells (rBMSCs) were cultured on the scaffold to evaluate cytotoxicity, cell proliferation, spreading, and osteogenic differentiation. Results Four types of scaffolds were obtained: mHAw-SiO2 (SHA), Mg-doped mHAw-SiO2 (SMHA), Sr-doped mHAw-SiO2 (SSHA), and Mg-Sr codoped mHAw-SiO2 (SMSHA). SHA was the most hydrophilic (WCA 5°), while SMHA was the least (WCA 8°); SMHA had the smallest pore size (247.40 ± 23.66 μm), while SSHA had the largest (286.20 ± 19.04 μm); SHA had the smallest Young's modulus (122.43 ± 28.79 MPa), while SSHA had the largest (188.44 ± 47.89 MPa); and SHA had the smallest compressive strength (1.72 ± 0.29 MPa), while SMHA had the largest (2.47 ± 0.25 MPa). The osteogenic active elements Si, Mg, and Sr were evenly distributed and could be sustainably released from the scaffolds. None of the scaffolds had cytotoxicity. SMSHA had the highest supporting cell proliferation and spreading rate, and its ability to promote osteogenic differentiation of rBMSCs was also the strongest. Conclusions These composite porous scaffolds not only have acceptable physical and chemical properties suitable for BTE but also have higher osteogenic bioactivity and can possibly serve as potential bone repair materials.

The T 2 spectrum obtained by inversion of the nuclear magnetic resonance logging echo signal can provide various petrophysical parameters to help technicians effectively identify the type of fluid. However, raw logging data with a low signal-to-noise ratio can cause inversion results to deviate from the truth. Therefore, a deep learning denoising method is proposed to eliminate the limitations of traditional mathematical transform methods. A one-dimensional deep convolutional generative adversarial networks model is designed to fit the noise distribution of actual logging data, then generate simulation data. A multi-scale echo denoising network (MsEDNet) is designed to adaptively learn the multi-exponential decay characteristics of the signal and the optimal transform space. The denoising dataset consists of simulation data and logging data, which is applied to train MsEDNet and improve the generalization performance. With effectiveness analysis and various denoising experiments, it is validated that the proposed method has excellent denoising performance on simulation data, logging data, and water tank data.

Background Orthopedics has made great progress with the development of medical treatment; however, large bone defects are still great challenges for orthopedic surgeons. A good bone substitute that can be obtained through bone tissue engineering may be an effective treatment method. Artificial hydroxyapatite is the main inorganic component of bones, but its applications are limited due to its fragility and lack of bone-active elements. Therefore, it is necessary to reduce its fragility and improve its biological activity. Methods In this study, we developed micro-hydroxyapatite whiskers (mHAws), which were doped with the essential trace active elements Mg2+ and Sr2+ through a low-temperature sintering technique, used silica complexes to improve the mechanical properties, and then manufactured the bionic porous scaffolds by extrusion molding and freeze-drying. Results Four types of scaffolds were obtained: mHAw-SiO2, Mg-doped mHAw-SiO2, Sr-doped mHAw-SiO2 and Mg-Sr-codoped mHAw-SiO2. These composite porous scaffolds have been suggested to have a sufficiently porous morphology with appropriate mechanical strength, are noncytotoxic, are able to support cell proliferation and spreading, and, more importantly, can promote the osteogenic differentiation of rBMSCs. Conclusion Therefore, these doped scaffolds not only have physical and chemical properties suitable for bone tissue engineering, but also have higher osteogenic bioactivity, and can be possibly serve as potential bone repair material.

Photocatalytic hydrogen generation over semiconductor photocatalysts has attracted considerable attention over the past few decades. This experiment is designed for sophomore- and higher-level undergraduates who are in the majors of materials chemistry, analytical chemistry, catalysis, or chemical engineering. In this experiment, CdS nanoparticles and nanosheets were first fabricated with a one-step direct-precipitation reaction and a two-step precipitation–ion-exchange reaction, respectively, and then used as photocatalysts for visible-light hydrogen evolution from water, in the presence of noble-metal Pt nanoparticles as in situ cocatalysts and sodium sulfide and sulfite (Na2S/Na2SO3) as sacrificial reagents. A gas chromatograph with a thermal-conductivity detector (GC-TCD) was used to quantitatively monitor the produced hydrogen gas. This interdisciplinary experiment is expected to give students an introduction to nanomaterial synthesis, the general process of photocatalytic hydrogen generation, and the principles and use of instruments. Upon the completion of the experiment, students understand how chemistry can be utilized for renewable-energy applications.

Influenza A virus is a crucial zoonotic pathogen that is prevalent in diverse avian and mammalian species. With the widespread emergence of novel avian influenza viruses (AIVs), diseases in humans caused by these viruses have increased. Thus, AIVs have become a critical concern to public health. Apart from respiratory symptoms, neurological symptoms can also be caused by AIV infections. The neurotropism of AIV can cause serious illnesses; therefore, it is considered a key criterion in the prognosis of the disease. To summarize the neurotropism of influenza viruses, we review the related findings on neurotropism of human influenza virus and AIV in the following three aspects: the clinical features of influenza virus-associated encephalopathy, the mechanism by which influenza virus invades the central nervous system, and the molecular mechanism of neurotropism.

This paper presents a game theoretic control strategy for optimal thermal load management of multiple buildings in a demand response aggregator. The electricity cost of the aggregator consists of two parts: an energy charge and a demand cost, the latter based on the aggregate peak demand over a billing horizon. We propose a non-cooperative game framework where an internal pricing mechanism is imposed with a Shapley value-based function to distribute the demand charge among the players. A Nash equilibrium problem is formulated and then transformed into a system of nonlinear equation solving problem based on the Nikaido-Isoda function. A generalized Newton-based algorithm is developed to find a Nash equilibrium of the formulated game. Simulation tests were carried out for a six-building aggregator to evaluate the performance of the proposed control strategy along with three baseline control methods. Test results showed that the proposed strategy could result in performance very close to the social optimum, with the Price of Anarchy of 1.002. The alliance stability could also be achieved in the test results.