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Fungal diseases could severely harm agricultural productions. To develop new antifungal agents, based on the Global Natural Products Social Molecular Networking, typical bromine isotope peak ratios, and ultraviolet absorptions, cultivation of the soft coral-derived endophytic fungi Aspergillus terreusEGF7-0-1 with NaBr led to the targeted isolation of 14 new brominated aromatic butenolides (1–14) and six known analogues (15–20). Their structures were elucidated by extensive spectroscopic analysis and quantum chemical calculations. Compounds 1–14exhibited wildly antifungal activities (against Colletotrichum gloeosporioides, Pestalotiopsis microspora, Fusarium oxysporumf. sp. cubense, Botrytis cinerea, and Diaporthe phoenicicola). The bioassay results showed that compounds 1–14exhibited excellent antifungal activities against C. gloeosporioides, with concentration for 50% of maximal effect (EC50) values from 2.72 to 130.41 nM. The mechanistic study suggests that compound 1may disrupt nutrient signaling pathways by reducing the levels of metabolites, such as carbohydrates, lipids, and amino acids, leading to an increase in low-density granules and a decrease in high-density granules in the cytoplasm, accompanied by numerous vacuoles, thereby inhibiting the growth of C. gloeosporioides. Monobrominated γ-butenolide 1may be expected to exploit a novel agriculturally antifungal leading drug. Meanwhile, compound M1has conformed antifugual activities against C. gloeosporioidesby papayas in vivo.

Plants convert solar energy and carbon dioxide into organic compounds through photosynthesis. Sucrose is the primary carbonate produced during photosynthesis. Sucrose phosphate synthase (SPS) is the key enzyme controlling sucrose biosynthesis in plants. There are at least three SPSgene families in higher plants, named A, B, and C. However, in monocotyledonous plants from Poaceae, there are at least five SPSgene families, named A, B, C, DIII, and DIV. Each family of SPSgenes in different plants shows a divergent expression pattern. So different families of SPSgenes participate in diverse biological functions, including sucrose accumulation, plant growth and production, and abiotic stress tolerance. SPS activity in plants is regulated by exogenous factors through gene expression and reversible protein phosphorylation. It is a practicable way to improve crop traits through SPSgene transformation. This work analyzes the cloning, phylogeny, and regulatory mechanism of the SPSgene in plants, reviews its biological function as well as its role in crop improvement, and discusses the challenges and future perspectives. This paper can serve as a reference for further study on plant SPSgenes and eventually for crop improvement.

With global eutrophication and increasingly stringent nitrogen discharge restrictions, dissolved organic nitrogen (DON) holds considerable potential to upgrade advanced wastewater denitrification because of its large contribution to low-nitrogen effluents and stronger stimulation effect for algae. Here, we show that DON from the postdenitrification systems dominates effluent eutrophication potential under different carbon sources. Methanol resulted in significantly lower DON concentrations (0.84 ± 0.03 mg/L) compared with the total nitrogen removal-preferred acetate (1.11 ± 0.02 mg/L) (p< 0.05, ANOVA). With our well-developed mathematical model (R2= 0.867–0.958), produced DON instead of shared (persist in both influent and effluent) and/or removed DON was identified as the key component for effluent DON variation (Pearson r= 0.992, p< 0.01). The partial least-squares path modeling analysis showed that it is the microbial community (r= 0.947, p< 0.01) rather than the predicted metabolic functions (r= 0.040, p> 0.1) that affected produced DON. Carbon sources rebuild the microorganism–DON interaction by affecting the structure of microbial communities with different abilities to generate and recapture produced DON to finally regulate effluent DON. This study revalues the importance of carbon source selection and overturns the current rationality of pursuing only the total nitrogen removal efficiency by emphasizing DON.

•Inactivated vaccine breakthrough infection with ancestral variants induced nearly undetectable nAbs against XBB variants.•Inactivated vaccine breakthrough infection with Omicron BA.1 or BA.5 evoked very weak nAbs against XBB variants.•BA.5 infection induced higher nAbs against XBB variants than BA.1 infection.

Reinforced concrete (RC) structures are common in engineering, and usually exposed to air or water, may be subjected to various blast scenarios. This paper aims to investigate the blast resistance of an air-backed RC slab against underwater contact explosions (UWCEs). A detailed numerical model based on CLE method considering explosive, water, air, and RC slab is developed to examine the structural behavior of the air-backed RC slab due to UWCEs. At first, the reliability of the numerical method is validated by comparing the numerical results of an UWCE test with experimental data. Then, the difference in dynamic behavior of air-backed and water-backed RC slabs due to UWCEs is explored with the calibrated model. The results indicate that the blast response of the air-backed slab induced by UWCE is fiercer than that of water-backed slab with equal charge mass. In addition, parametric studies are also conducted to explore the effects of the charge mass, standoff distance, reinforcement spacing, concrete compression strength, and boundary condition on the blast performance of the air-backed RC slab.

Tumor angiogenesis is an essential factor for tumor growth and antiangiogenic therapy. To simulate the blood perfusion characteristics of human renal cell carcinoma (RCC) longitudinally in the process of tumor growth, multimodal ultrasound examination was performed on 40 orthotopic xenograft RCC mouse models. According to tumor maximum diameter (d), tumor growth progress was divided into 3 steps: d≤ 5 mm, 5 mm < d≤ 10 mm, and d> 10 mm. Color Doppler flow imaging (CDFI), superb microvascular imaging (SMI), and contrast-enhanced ultrasound were administered to monitor tumor perfusion characteristics. The abundance of tumor vascularity on CDFI and SMI was divided into grades 0 to III in ascending order, and their distribution range was categorized into types I to IV. As a result, heterogeneous echogenicity and irregular shape were more common in tumors d> 10 mm than those d< 10 mm (P< 0.001 for both). Tumor perfusion grade and type on both CDFI and SMI made statistic difference among different growth steps, with higher ratio of hypervascular characteristic in bigger ones (all P< 0.05). Tumor in the same growth step had a higher perfusion grade on SMI than that on CDFI (P< 0.001). On contrast-enhanced ultrasound, heterogeneous enhancement was more common in those >10 mm (P< 0.001). It can be concluded that the blood perfusion characteristics of RCC keep on changing during its growth process. In addition, SMI is more sensitive in evaluating tumor perfusion than CDFI.

The emerging SARS-CoV-2 variants, commonly with many mutations in S1 subunit of spike (S) protein are weakening the efficacy of the current vaccines and antibody therapeutics. This calls for the variant-proof SARS-CoV-2 vaccines targeting the more conserved regions in S protein. Here, we designed a recombinant subunit vaccine, HR121, targeting the conserved HR1 domain in S2 subunit of S protein. HR121 consisting of HR1–linker1–HR2–linker2–HR1, is conformationally and functionally analogous to the HR1 domain present in the fusion intermediate conformation of S2 subunit. Immunization with HR121 in rabbits and rhesus macaques elicited highly potent cross-neutralizing antibodies against SARS-CoV-2 and its variants, particularly Omicron sublineages. Vaccination with HR121 achieved near-full protections against prototype SARS-CoV-2 infection in hACE2 transgenic mice, Syrian golden hamsters and rhesus macaques, and effective protection against Omicron BA.2 infection in Syrian golden hamsters. This study demonstrates that HR121 is a promising candidate of variant-proof SARS-CoV-2 vaccine with a novel conserved target in the S2 subunit for application against current and future SARS-CoV-2 variants.

The preparation of highly active and low-cost electrocatalysts is a major challenge for water electrolysis. Here, iron and oxygen codoped cobalt phosphide nanoparticles (O–Co1–xFexPy, x= 0–0.42) are prepared by reacting metal–organic framework with phosphorus under solvothermal conditions. When electrochemically catalyzing the oxygen evolution reaction (OER) in 1 M KOH, O–Co0.58Fe0.42Pysupported on the nickel foam exhibits the best activity, with only 232 mV overpotential to reach 10 mA cm–2OER current densities. O–Co0.58Fe0.42Pyis robust toward the long-term OER, and surface phosphide layers transform to (oxy)hydroxides during the OER. O–Co1–xFexPyalso shows better OER activity than Co3O4nanoparticles and commercial IrO2. The abundant electrochemically active sites exposed by the highly porous morphology and the electron interactions between Co and Fe that accelerate the OER intermediate adsorption process could account for the observed high OER activity.

Comprehensive analyses of the metabolite spectra of Aspergillussp. EGF 15-0-3 under different culture conditions revealed the presence of unique environmental-induced metabolites exclusively from the rice medium. Subsequent target isolation afforded four unprecedented indole diketopiperazine-based hybrids with a pyrano[3′,2′:7,8]isochromeno[4,3-b]pyrazino[2,1-i]indole core (1and 2) or a spiro[piperazine-2,2′-pyrano[3,4,5-de]chromene] scaffold (3and 4). Putative biosynthetic pathways for 1–4, with Diels–Alder cycloadditions as key steps, were proposed. 1–4exhibited selective cytotoxicities among several human cancer cells.

Designing electrocatalysts for the water oxidation reaction (WOR) and the methanol oxidation reaction (MOR) using earth-abundant elements is crucial for the development of water electrolyzers and direct methanol fuel cells. We report the synthesis of nickel phosphide nanospheres with different crystallinities (Ni2P-H, Ni2P-L, and Ni-P-a) by reacting Ni-based metal–organic frameworks and P4solvothermally. All the nickel phosphide nanospheres synthesized are active toward WOR and MOR, and Ni2P-L, with amorphous/crystalline heterostructures, shows the best electrocatalytic performance. For WOR, the overpotential at 10 mA cm–2for Ni2P-L on Ni foam is 300 mV in 1 M KOH (loading 0.8 mgNi+Pcm–2), and the Tafel slope is ∼86.4 mV dec–1. For MOR, Ni2P-L on carbon paper has the highest current density of 427.0 mA mg–1at 1.74 VRHEin 1 M KOH + 0.5 M CH3OH. Structural characterizations and electrochemical kinetic studies suggest that the high electrocatalytic activity of Ni2P-L originates from the abundant electrochemically active sites exposed owing to the amorphous phase and the electron interaction between Ni and P, which tunes the WOR intermediate (OH*) adsorption energy. Conversion of phosphides to (oxy)hydroxides at the surface is also observed after long-term WOR.

A photoredox-catalyzed regio- and stereoselective trifluoroethylation reaction of enamides using commercially available 2,2,2-trifluoroethyl iodide as trifluoroethylating agents has been developed, furnishing geometrically defined and synthetically and physiochemically pivotal β-trifluoroethylated enamides bearing a diverse range of functional groups.

Intracellular delivery of functional macromolecules using peptide transduction domains (PTDs) is an exciting technology with both experimental and therapeutic applications. Recent data indicate that PTD-mediated transduction occurs via fluid-phase macropinocytosis involving an intracellular pH drop to ∼5. Nitrilotriacetic acid (NTA)-coordinated metals avidly bind hexahistidine-tagged macromolecules, including peptides and proteins. Histidine’s imidazole ring has a pKaof 6, making this an attractive target for the biological pH drop of PTD-mediated macropinocytotic delivery. The objective of this study was to develop a pH-sensitive PTD delivery peptide (NTA3-PTD). We demonstrate the in vitrofunction of this novel peptide by delivering fluorescently labeled peptides (1.6 kDa) and functional enzymes, β-galactosidase (119 kDa) and Cre recombinase (37 kDa). Furthermore, the NTA3-PTD peptide was able to deliver functional Cre recombinase in an in vivomouse model.

High quality perovskite films with large columnar grains are greatly desired for efficient perovskite solar cells. Here, low volatility N-methyl-2-pyrrolidone (NMP) was added in MAI/IPA solution in a two-step spin-coating method, which promoted the conversion of lead iodide to perovskite. The perovskite films were annealed by a closed-steam annealing method to prolong the recrystallization process of perovskite films assisted by the residual NMP. It leaded to high quality CH3NH3PbI3perovskite films with large columnar grains due to its enhancement of the Oswald ripening. The large grain perovskite film leaded to efficient carrier transformation and injection, and low recombination. The photovoltaic performance of the perovskite solar cells was improved significantly.

Penicilloneines A (1) and B (2) are the first reported quinolone–citrinin hybrids. They were isolated from the starfish-derived fungus Penicilliumsp. GGF16-1-2, and their structures were elucidated using spectroscopic, chemical, computational, and single-crystal X-ray diffraction methods. Penicilloneines A (1) and B (2) share a common 4-hydroxy-1-methyl-2(1H)-quinolone unit; however, they differ in terms of citrinin moieties, and these two units are linked via a methylene bridge. Penicilloneines A (1) and B (2) exhibited antifungal activities against Colletotrichum gloeosporioides, with lethal concentration 50 values of 0.02 and 1.51 μg/mL, respectively. A mechanistic study revealed that 1could inhibit cell growth and promote cell vacuolization and consequent disruption of the fungal cell walls via upregulating nutrient-related hydrolase genes, including putative hydrolase, acetylcholinesterase, glycosyl hydrolase, leucine aminopeptidase, lipase, and beta-galactosidase, and downregulating their synthase genes 3-carboxymuconate cyclase, pyruvate decarboxylase, phosphoketolase, and oxalate decarboxylase.

A transition metal-free radical process for the selective α,β-dehydrogenation of saturated amides under mild conditions is developed. Utilizing radical activation strategy, the challenging issue associated with the low α-acidity of amides is resolved. For the first time, α,β-unsaturated Weinreb amides and acrylamides could be efficiently prepared directly from corresponding saturated amides. Mechanistic studies confirm the radical nature of this transformation. Two gram scale α,β-dehydrogenation have also been performed to demonstrate the utility of this method.

The series of metal 8-hydroxyquinolates {[Ni7(μ2-L1)6(μ3-L1)2(OAc)2(μ7-L2)(OCH3)]·CH3OH·CH3CN} (1), {[Ni7(μ2-L1)6(μ3-L1)3(SCN)2(μ7-L2)(CH3CN)]·(CH3OH)2·CH3CN} (2), [Ni5Dy2(μ2-L1)6(OAc)4(μ7-L2)2] (3), [Ni6Dy(μ2-L1)6(μ3-L1)2(OAc)3(μ7-L2)(OCH3)] (4), and [Ni6Dy(μ2-L1)6(μ3-L1)2(OAc)2(NO3)(OH)2(OCH3)2] (5) (HL1= 8-hydroxyquinoline, H3L2= 1,1,1-tris(hydroxymethyl)ethane) has been solvothermally prepared. Those clusters feature a heptanuclear disklike structure with 8-hydroxyquinolines as corner ligands restricting the expansion of the triangular lattice in spite of the metal ions or auxiliary coligands. The magnetic properties of those complexes vary according to metal ions and auxiliary coligands, for which slow magnetic relaxation is found in 5.

Recently, perovskite solar cells have attracted great attention because of their outstanding photovoltaic performance and ease of fabrication. High-quality perovskite films hold a key in getting highly efficient perovskite solar cells. Solution-processed fabrication technique is the most widely adopted for preparing perovskite films because of its low cost. In the solution-proceed perovskite films, solvents not only play the role of dissolving the solute but also participate in the crystallization of perovskite. In the one-step method, solvents play key roles in controlling morphology, widening process window, and achieving room-temperature crystallization of perovskite films. In addition, the solvents play important roles in controlling the nuclei/growth, suppressing volume expansion during the two-step method. Especially, the solvent can induce grain coarsening during the annealing process. A deep understanding of the multiplicity of roles during the formation of perovskite films will help understand the formation mechanism of perovskite films. Here, a systematic review on the progress in fabrication of high-quality perovskite films by making use of solvent to control the crystallization is presented. Meanwhile, we elucidate the key roles of solvent in the fabrication of high-quality perovskite films.

Perovskite films are usually fabricated by a solution-processed method due to its low cost and ease of fabrication. The organic solvent plays multiple roles in the growth of perovskites. Here, we investigate the growth of methylammonium lead iodide perovskite and its intermediate phase from microdroplets containing various solvents. The perovskite intermediate phase inclines to grow in the direction of its (020) plane from polar aprotic solvents at low temperature. At high temperature, the growth of perovskites depends on the structure of solvent molecules. The intermediate phase still grows from the solvents with a short chain structure. It tends to form smooth films containing radial domains with dimensions in tens of microns, which consist of nanocrystals due to annealing effects. However, perovskite grains grow directly from the solvents with a ring structure. It tends to form smooth thin films by joining the large hexagonal perovskite crystals together. It provides a guidance to prepare high quality perovskite films for high performance optoelectronic devices.

Black soil is one of the most precious soil resources on earth because it has abundant carbon stocks and a relatively high production capacity. However, decreasing organic matter after land reclamation, and the effects of long-term inputs of organic carbon have made it less fertile black soil in Northeast China. Straw return could be an effective method for improving soil organic carbon (SOC) sequestration in black soils. The objective of this study was to evaluate whether straw return effectively increases SOC sequestration. Long-term field experiments were conducted at three sites in Northeast China with varying latitudes and SOC densities. Study plots were subjected to three treatments: no fertilization (CK); inorganic fertilization (NPK); and NPK plus straw return (NPKS). The results showed that the SOC stocks resulting from NPKS treatment were 4.0 and 5.7% higher than those from NPK treatment at two sites, but straw return did not significantly affect the SOC stocks at the third site. Furthermore, at higher SOC densities, the NPKS treatment resulted in significantly higher soil carbon sequestration rates (CSR) than the NPK treatment. The equilibrium value of the CSR for the NPKS treatment equated to cultivation times of 17, 11, and 8 years at the different sites. Straw return did not significantly increase the SOC stocks in regions with low SOC densities, but did enhance the C pool in regions with high SOC densities. These results show that there is strong regional variation in the effects of straw return on the SOC stocks in black soil in Northeast China. Additional cultivations and fertilization practices should be used when straw return is considered as an approach for the long-term improvement of the soil organic carbon pool.

High-quality perovskite films can be fabricated from Lewis acid–base adducts through molecule exchange. Substantial work is needed to fully understand the formation mechanism of the perovskite films, which helps to further improve their quality. Here, we study the formation of CH3NH3PbI3perovskite films by introducing some dimethylacetamide into the PbI2/N,N-dimethylformamide solution. We reveal that there are three key processes during the formation of perovskite films through the Lewis acid–base adduct approach: molecule intercalation of solvent into the PbI2lattice, molecule exchange between the solvent and CH3NH3I, and dissolution–recrystallization of the perovskite grains during annealing. The Lewis base solvents play multiple functions in the above processes. The properties of the solvent, including Lewis basicity and boiling point, play key roles in forming smooth perovskite films with large grains. We also provide some rules for choosing Lewis base additives to prepare high-quality perovskite films through the Lewis adduct approach.

In high-power systems of proton exchange membrane fuel cells (PEMFC), cooling systems for the balance of plants (BOP) play an extremely important role in maintaining the temperature of the key components of the fuel cell system. To evaluate the effect of the PEMFC BOP cooling system on the fuel cell system efficiency, a Simulink model of the fuel cell system and an AMEsim model of the cooling system for the BOP system are established based on experimental data. A co-simulation is conducted based on the established models to determine the effects of fuel cell stack output power, coolant flowrate, radiator fan speed, and temperature control strategies on the parasitic power consumption and fuel cell system efficiency. The simulation results show that with an increase in the stack output power, coolant flowrate, and radiator fan speed, the parasitic power of the BOP cooling system increases and the system efficiency of PEMFC decreases. With an increase in the opening temperature of the radiator fan, the parasitic power of the BOP cooling system decreases and the system efficiency of the PEMFC increases. Compared with the rule-based control strategy, the radiator fan speed control strategy based on the PID controller achieves lower parasitic power. The research presented in this paper is helpful for further development of efficient fuel cell vehicle thermal management system.

A method for the synthesis of α-hydroxyl and α-amino pyridinyl esters via photoreductive dual radical cross-coupling catalyzed by the super-organoreductant CBZ6has been developed. A wide range of 2-pyridinylation and 4-pyridinylation of either α-ketoesters or imine derivatives has been achieved. The applications in the synthesis of pyridinyl amino-hydroxyl acids as well as a new chiral oxazoline ligand have also been accomplished.

Perovskite solar cells have a puzzling phenomenon of current hysteresis. Here, we modulate the hysteresis by applying a poling voltage. Charge accumulations are detected in the perovskite solar cells. Two interacting capacitors are identified through dynamic voltage measurement. We elucidate that the current hysteresis originates mainly from the polarization and depolarization of electric dipoles of CH3NH3+under an external electric field due to the intrinsic ferroelectric properties of perovskite. The polarization leads to charge accumulation at the surface of perovskite, which establishes a polarization-induced electric field. The polarization-induced electric field affects the charge transport inside the solar cells, resulting in the current hysteresis. The polarization of electric dipoles can be modified by the poling and sweeping voltage, which makes the hysteresis exhibit a history-dependent effect.

In this paper, we propose a Detail-Preserving Sparse Model (DPSM) for de-noising of images that are usually interfered by noise on the Wireless Multimedia Sensor Network (WMSN). Specifically, based on the Structural SIMilarity (SSIM), the DPSM first incorporates a structural-preserving constraint, which enables the structure in the reconstructed image to be close to the ideal no-noise image. In addition, the DPSM adopts a residual ratio as the stopping condition of the sparse solution algorithm (e.g., Orthogonal Matching Pursuit), which enables the structures to be reconstructed under high noise conditions. The experimental results on several WMSN images have demonstrated the superiority of the proposed DPSM method over several well-known de-noising approaches in terms of PSNR and SSIM.

According to the characteristics of hydraulic support intelligent control, the hydraulic support control system is designed and analyzed based on Controller Area Network (CAN) technology. Through the characteristics of CAN-bus network communication, the host computer communication and monitoring requirements is researched, and the mission of function is established. The data transmission program is designed under MSComm ActiveX which accomplishes stable communication function. Based on hydraulic test bench, the reliability of data transmission is verified which provides some guidance for the development of the intelligent control.

This paper reviews and demonstrates how to use digital technology to design the ecological environment. Through the analysis and summary of current research fields and status quo of eco-design, we explain the development of ecosystem design in life and building, and propose the key issues to be addressed, discuss the inadequacies of current research, and predict the next main research tendency of ecosystem design based on digital technology.

This paper summarizes research progress of 3D style design based on sketching, especially focuses on 3D modeling method based on sketching, 3D stroke fitting. The future research direction on multi-strokes fitting and the use of digital pen pressure and other information for style design are proposed.

Adding elevators to old buildings bring not only technical issues as well as economic and social problems, especially the conflicts among different stakeholders. This paper, selecting some representative districts and buildings in Guangzhou, focuses on the public opinions on this issue. Methodologies combining quantitative and qualitative analysis including in-depth interview and questionnaire inquires are approached with the residents concerned, SPSS software, and the results are used for cross section analysis and comparative analysis against the in-depth interview results. At last, a relative accurate reflection of the opinions and views of the residents regarding add elevators to old buildings are presented, and some relevant policy advices are put forward accordingly.

Trigoflavidols A (1) and B (2), tetranorditerpenoid dimers possessing a rearrangement skeleton with a spiroketal core moiety, and trigoflavidol C (3), a hexanorditerpenoid, have been isolated from Trigonostemon flavidusalong with two known compounds. Compounds 1and 2showed moderate antimicrobial activities (MIC values: 3.12–6.25 μg/mL) against Staphylococcus aureus, 8#MRSA, and 82#MRSA, and 1, 2, and 5showed weak activities (IC50values: 3.75–28.99 μM) against various human tumor cell lines.

Rotating instability can be observed in the tip flow region of axial compressor stage while stable operation. In order to investigate the noise characteristics in a multi-stage axial compressor, the noise inner compressor casing is measured simultaneously with the vibration of the rotor blades on a high pressure compressor component rig testing. An azimuthal mode analysis and theoretical formulation of the rotating source mechanism are applied to the unsteady pressure at the casing wall immediately upstream of the inlet plane of the rotor. It is shown that RIs might be described by a group of superimposed modes. This is the reason why RIs can be identified as an amplitude increase in a frequency band. The mode orders of RI are consecutively numbered riseing with frequency. The frequency in the source frame (ωN) closed to the frequency in the rotating frame (ωN) can be got well recovered. The results presented in this paper can be a reference for further understanding of the characteristics of unsteady flow field and the effects of the high intensity sound waves on the rotor blades.