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Nonribosomal peptides (NRPs) are biosynthesized by nonribosomal peptide synthetases (NRPSs) and are widely distributed in both terrestrial and marine organisms. Many NRPs and their analogs are biologically active and serve as therapeutic agents. The adenylation (A) domain is a key catalytic domain that primarily controls the sequence of a product during the assembling of NRPs and thus plays a predominant role in the structural diversity of NRPs. Engineering of the A domain to alter substrate specificity is a potential strategy for obtaining novel NRPs for pharmaceutical studies. On the basis of introducing the catalytic mechanism and multiple functions of the A domains, this article systematically describes several representative NRPS engineering strategies targeting the A domain, including mutagenesis of substrate-specificity codes, substitution of condensation-adenylation bidomains, the entire A domain or its subdomains, domain insertion, and whole-module rearrangements. [ABSTRACT FROM AUTHOR]

It is more difficult to accurately control the cycle fuel mass of a gasoline engine as the injection pressure increases, and the difference in the injection mass flow will become intense due to the machining error of GDI injector structural parameters. In order to guarantee the uniform cycle fuel mass of the GDI injector, this paper investigates the effect of the inlet orifice on the injection mass flow and the sensitivity of inner-flow characteristics in the GDI injector nozzle to the inlet orifice radius by the single factor analysis method. The results show that the local resistance of the injector nozzle will decrease and the discharge coefficient will rise due to the increase in the inlet orifice radius; the sensitivity of cycle fuel mass to the inlet orifice radius is most strong at r = 0.02 mm, and its accuracy should be improved when grinding the chamfer of the nozzle inlet; the sensitivity coefficient of the inlet orifice radius will rise up, and the machining accuracy of the inlet orifice radius should be improved as there is an increase in injection pressure. [ABSTRACT FROM AUTHOR]

All-solid-state lithium batteries (ASSLBs) are regarded as the most promising alternative to traditional liquid lithium-ion batteries due to their high-energy density and excellent safety. As an important part of ASSLBs, composite polymer electrolytes (CPEs) with excellent comprehensive performance have attracted wide attention from researchers. Herein, a series of CPEs were prepared by employing Li6.4Ga0.2La3Zr2O12 (LGLZO) submicron particles with cubic phase as fillers in polyethylene oxide (PEO) matrix. The tape-casting method was employed to prepare PEO-LiTFSI-x% LGLZO (CPE-x, where x = 0–80). In these CPE-x, the CPE-40 exhibits elevated ionic conductivity (6.20 × 10−5 S cm−1 at 20 °C and 1.88 × 10−4 S cm−1 at 60 °C), attractive Li+ transference number (0.31 at 60 °C), low activation energy barrier of lithium-ion migration, wide electrochemical window, and high critical current density of 1.3 mA cm−2. Furthermore, the LiFePO4 | CPE-40 | Li batteries deliver outstanding cycle performance (capacity retention of 85.43% after 225 cycles at 0.2C and 60 °C) and rate performance. These results show that the PEO-base solid-state electrolytes filled with submicron LGLZO particles possess a broad application prospect. [ABSTRACT FROM AUTHOR]

Spinel LiMn2O4-based lithium-ion batteries are widely applied in electric two-wheeler and low-speed vehicles due to their low cost and low toxicity. Nevertheless, the Mn deposition at the anode originated from Mn dissolution of LiMn2O4 causes a poor elevated temperature cycle life of graphite/LiMn2O4 batteries. Herein, a graphite/LiFePO4 cell with specific Mn2+ added in the electrolyte is provided as an efficient evaluation method to research Mn2+ deposition. Besides, an effective strategy by adding a ligand hexamethylenetetramine (HMTA) as an electrolyte additive is proposed to prevent Mn2+ depositing. HMTA effectively "locks in" Mn2+ through strong coordination, as confirmed by Raman spectroscopy and density functional theory (DFT) calculations. Moreover, the CV and XPS results indicate that the adsorption of HMTA is able to significantly inhibit side reactions at the anode/electrolyte interface. By adopting this strategy, the capacity retention of graphite/LiMn2O4 cell is enhanced from 68.9% to 79.0% at 0.5 C after 100 cycles under 60 °C when adding 0.5% HMTA additive into the blank electrolyte. This work provides a new insight into revealing the mechanism of Mn2+ regulation by introducing HMTA and improving the electrochemical performance of graphite/LiMn2O4 batteries at elevated temperature. [ABSTRACT FROM AUTHOR]

Drought stress is seriously affecting the growth and production of crops, especially when agricultural irrigation still remains quantitatively restricted in some arid and semi-arid areas. The identification of drought-tolerant genes is important for improving the adaptability of maize under stress. Here, we found that a new member of the actin-depolymerizing factor (ADF) family; the ZmADF5 gene was tightly linked with a consensus drought-tolerant quantitative trait locus, and the significantly associated signals were detected through genome wide association analysis. ZmADF5 expression could be induced by osmotic stress and the application of exogenous abscisic acid. Its overexpression in Arabidopsis and maize helped plants to keep a higher survival rate after water-deficit stress, which reduced the stomatal aperture and the water-loss rate, as well as improved clearance of reactive oxygen species. Moreover, seventeen differentially expressed genes were identified as regulated by both drought stress and ZmADF5, four of which were involved in the ABA-dependent drought stress response. ZmADF5-overexpressing plants were also identified as sensitive to ABA during the seed germination and seedling stages. These results suggested that ZmADF5 played an important role in the response to drought stress. [ABSTRACT FROM AUTHOR]

In order to precisely ascertain the temperature at the hot spot within the intermediate joint of a three-core cable, this study focused on a 10 kV three-core cable joint as its primary subject. A three-dimensional finite element model of the cable joint was constructed, enabling the calculation of both the steady-state hot spot temperature field distribution and the transient temperature rise curve of the joint. Employing a one-dimensional transient thermal path model for the cable body, a radial inversion model for the cable core temperature was established. Through simulating the transient temperature field of the cable joint under varying currents, a fitting relationship was determined for the axial temperature points of the cable core. Subsequently, an inversion perception model was devised to calculate the hot spot temperature of the cable joint based on temperature measurements at specific points on the outer surface of the cable. Under both continuous and periodic loads, the inversion results revealed a consistent trend in the temperature at the joint crimping point with the finite element calculation outcomes, demonstrating a maximum error of within 3 degrees Celsius. This verification underscores the precision of the temperature combination inversion method when applied to three-core cable joints. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) necessitates secure communication and high availability among objects at the network edge to ensure reliable object-to-object transactions. In the IoT networks, despite resource limitations, especially at the edge of the network, the potential for error is high. Therefore, a mechanism to increase the reliability, lifetime, and stability of the network is necessary. In this paper, we introduce a trust evaluation framework based on a reliability-based friendly relationship method in IoT networks. We present a conceptual trust model that captures the overall performance of the IoT social network based on parameters such as nodes’ communication history experiences. Trust in the IoT network is built upon a harmonious communication environment that aligns with the trustworthiness of each object and its ability to maintain continuous interactions. We propose an empirical Trust Indicator (TI) that captures individual agents’ experiences in IoT groups, considering the results of system executions, current experience values, and timestamps of interactions. Mathematical models are developed to analyze the dynamics of trust, including trust increase through increased reliability and collaborative interactions and trust decay due to non-cooperative interactions and lack of communication. The model parameters in IoT groups through simulation show that in this system based on the level of reliability and its increase or decrease, its direct effect can be evaluated by quantitative measurement of mean time to failure (MTTF), which is a measure of devices trust and the network itself. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO)-based electrolytes are considered to be promising for all-solid-state battery, benefiting from the superior flexibility, excellent processability and well compatibility. However, the low ionic conductivity at room temperature and poor stability under high voltage limit their further application. Herein, ZIF-8@PVDF-HFP/PEO (PPZ) solid electrolyte was successfully prepared by facial electrospinning process. On one side, the cooperation of PVDF-HFP and ZIF-8 was benefit to decrease the crystallization degree of PEO and thus promoted the Li+ transfer. Moreover, the in-situ formed LiF layer derived from the decomposition of PVDF-HFP protected the electrolyte from contacting directly with the electrode, contributing to a stable electrode/electrolyte interface. The results demonstrated that the electrochemical stability and mechanical property of PPZ electrolyte were significantly improved when compared to the bare PEO electrolyte. The tensile strength increased from 0.5 to 6.7 MPa and the Li+ transference number enlarged from 0.17 to 0.48. More importantly, the assembled LCO(LiCoO 2)||PPZ||Li all-solid-state battery delivered a discharge specific capacity of 144.7 mAh g-1 at 0.2 C, nearly 1.6 times than that of the LCO||PEO||Li (90.7 mAh g-1). Besides that, the retention maintained at 86.3 % even after 200 cycles, manifesting a long-term cycling stability. This work provides a new idea for the practical application of PEO under high voltage. [ABSTRACT FROM AUTHOR]

The matching of poly(ethylene oxide) (PEO)-based electrolytes with ultrahigh-nickel cathode materials is crucial for designing new-generation high-energy-density solid-state lithium metal batteries (SLMBs), but it is limited by serious interfacial side reactions between PEO and ultrahigh-nickel materials. Here, a high-concentration electrolyte (HCE) interface with a customized Li + solvation sheath is constructed between the cathode and the electrolyte. It induces the formation of an anion-regulated robust cathode/electrolyte interface (CEI), reduces the unstable free-state solvent, and finally achieves the compatibility of PEO-based electrolytes with ultrahigh-nickel cathode materials. Meanwhile, the corrosion of the Al current collector caused by lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) ions is prevented by lithium difluoro(oxalato)borate (LiDFOB) ions. The synergistic effect of the double lithium salt is achieved by a well-tailored ratio of TFSI - and DFOB - in the first solvation sheath of Li + . Compared with reported PEO-based SLMBs matched with ultrahigh-nickel (Ni ≥ 90%) cathodes, the SLMB in this work delivers a high discharge specific capacity of 216.4 mAh g -1 (0.1C) even at room temperature. This work points out a direction to optimize the cathode/electrolyte interface.

Harnessing cutting-edge technologies to enhance crop productivity is a pivotal goal in modern plant breeding. Artificial intelligence (AI) is renowned for its prowess in big data analysis and pattern recognition, and is revolutionizing numerous scientific domains including plant breeding. We explore the wider potential of AI tools in various facets of breeding, including data collection, unlocking genetic diversity within genebanks, and bridging the genotype-phenotype gap to facilitate crop breeding. This will enable the development of crop cultivars tailored to the projected future environments. Moreover, AI tools also hold promise for refining crop traits by improving the precision of gene-editing systems and predicting the potential effects of gene variants on plant phenotypes. Leveraging AI-enabled precision breeding can augment the efficiency of breeding programs and holds promise for optimizing cropping systems at the grassroots level. This entails identifying optimal inter-cropping and crop-rotation models to enhance agricultural sustainability and productivity in the field., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Benefiting from high energy density of ultrahigh-nickel cathode materials and good safety of PEO-based electrolytes, PEO-based ultrahigh-nickel solid-state lithium batteries (SLMBs) are considered to be new-generation energy storage devices. However, the incompatibility of ultrahigh-nickel cathode materials and PEO-based electrolytes is the main challenge due to serious interfacial side reactions. Therefore, the modification of the cathode/electrolyte interface is crucial. Herein, the residual lithium on the surface of LiNi 0.9 Co 0.06 Mn 0.04 O 2 is utilized to construct an interfacial coating layer by reacting with H 3 BO 3 . The in situ formed x Li 2 O-B 2 O 3 coating layer (LBO1-NCM) with high ionic conductivity can be regulated with different crystal structures during the sintering process. Besides, an all-solid-state three-electrode cell is fabricated, which verifies that the x Li 2 O-B 2 O 3 coating can effectively stabilize the interface. Astonishingly, uneven Li anode deposition is observed in SLMBs, which is caused by the breakage of PEO molecular chains due to the strong oxidation of the cathode, while this crosstalk is also suppressed by the x Li 2 O-B 2 O 3 coating layer. Consequently, Li|PEO|LBO1-NCM achieves a substantially improved electrochemical performance, exhibiting 90.5% of capacity retention after 100 cycles for the coin cell and 80.3% of capacity retention after 200 cycles for the pouch cell. Apparently, the targeted modification of interfaces should be paid as much attention as electrolyte optimization in SLMBs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Lithium (Li) metal is regarded as a potential candidate for the next generation of lithium secondary batteries, but it has poor cycling stability with the broadly used carbonate-based electrolytes due to the uncontrollable dendritic growth and low Coulombic efficiency (CE). LiNO 3 is an effective additive and its limited solubility (<800 ppm) in carbonate-based electrolytes is still a challenge, as reported. Herein, using BF 3 (Lewis acid) is proposed to enhance the solubility of LiNO 3 in carbonate-based electrolytes. The dissolved NO 3 can be involved in the first solvation shell of Li - can be involved in the first solvation shell of Li + , reducing the coordination number of PF 6 is proved to be preferentially reduced on Li metal by differential electrochemical mass spectrometry so that the decomposition of PF - and EC is suppressed. Therefore, a SEI layer containing Li 3 N can be obtained, which exhibits high lithium-ion conductivity, achieving even and dense Li deposits. Consequently, the CE of Li||Cu cell with BF - is proved to be preferentially reduced on Li metal by differential electrochemical mass spectrometry so that the decomposition of PF 6 can be increased to 98.07%. Moreover, the capacity retention of Li||LiFePO - and EC is suppressed. Therefore, a SEI layer containing Li 3 N can be obtained, which exhibits high lithium-ion conductivity, achieving even and dense Li deposits. Consequently, the CE of Li||Cu cell with BF 3 /LiNO 3 can be increased to 98.07%. Moreover, the capacity retention of Li||LiFePO 4 with a low N/P ratio (3:1) is as high as 90% after 300 cycles (≈1500 h). This work paved a new way for incorporating LiNO 3 into carbonate-based electrolytes and high-performance lithium metal batteries., (© 2023 Wiley‐VCH GmbH.)

The ether-based electrolytes show excellent performance on anodes in sodium-ion batteries (SIBs), but they still show poor compatibility with the cathodes. Here, ether electrolytes with NaBF 4 as the main salt or additive were applied in NFM//HC full cells and showed enhanced performance than the electrolyte with NaPF 6 . Then, BF 4 - was found to have a stronger interaction with Na + , which could reduce the solvation of Na + with the solvent, thus inducing the formation of the cathode electrolyte interface (CEI) and solid electrolyte interface (SEI) layers rich in inorganic species. Moreover, the morphology, structure, composition, and solubility of CEI and SEI were explored, concluding that NaBF 4 could induce more stable CEI and SEI layers rich in B-containing species and inorganics. This work proposes using NaBF 4 as the main salt or additive to improve the performance of ether electrolytes in NFM//HC full cells, which provides a strategy to improve the compatibility of ether-based electrolytes and cathodes.