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Advances in x-ray free electron lasers have made ultrafast scattering a powerful method for investigating molecular reaction kinetics and dynamics. Accurate measurement of the ground-state, static scattering signals of the reacting molecules is pivotal for these pump-probe x-ray scattering experiments as they are the cornerstone for interpreting the observed structural dynamics. This article presents a data calibration procedure, designed for gas-phase x-ray scattering experiments conducted at the Linac Coherent Light Source x-ray Free-Electron Laser at SLAC National Accelerator Laboratory, that makes it possible to derive a quantitative dependence of the scattering signal on the scattering vector. A self-calibration algorithm that optimizes the detector position without reference to a computed pattern is introduced. Angle-of-scattering corrections that account for several small experimental non-idealities are reported. Their implementation leads to near quantitative agreement with theoretical scattering patterns calculated with ab-initio methods as illustrated for two x-ray photon energies and several molecular test systems.

In this review, several mechanisms of antihypertensive peptides derived from food and its by-products were summarized. Mechanisms based on the RAAS system such as ACE/Ang Ⅱ/AT1R signaling pathways and ACE2/Ang (1-7)/MasR signaling pathways were included. Mechanisms targeting at KNOS system including PI3K/Akt/eNOS signaling pathway, PPAR-γ/caspase3/MAPK/eNOS signaling pathway and L-type Ca2+ channel were also discussed. In addition, the pathways of reducing blood pressure by inhibiting endothelin-converting enzyme (ECE) activity discovered in recent years were also introduced.

In order to solve the problem of low first time yield rate of engine clearance size in aircraft assembly plant C Six Sigma DMAIC (define, measure, analyze, improve and control) method was introduced to analyze the engine installation process. Multiple regression analysis and other methods were used to determine the key factors affecting the clearance size and their influence degree, and the optimal parameter range was obtained by linear fit-ting, and a detailed control plan was made. The analysis results of the control chart show that the improved clear-ance size is in a stable state of the process, and the first time yield rate of engine installation has increased from 65.2% before the improvement to 95%. Conclusion:quality control based on Six Sigma DMAIC method has a pos-itive effect on reducing production process variation and improving production efficiency.

Phosphorus (P) starvation in rice facilitates the reutilization of root cell wall P by enhancing the pectin content. NaCl modulates pectin content, however, it is still unknown whether NaCl is also involved in the process of pectin regulated cell wall P remobilization in rice under P starved conditions. In this study, we found that 10 mmol/L NaCl increased the shoot and root biomasses under P deficiency to a remarkable extent, in company with the elevated shoot and root soluble P contents in rice. Further analysis indicated that exogenous NaCl enhanced the root cell wall P mobilization by increasing the pectin methylesterase activity and uronic acid content in pectin suggesting the involvement of NaCl in the process of cell wall P reutilization in P starved rice roots. Additionally, exogenous NaCl up-regulated the expression of P transporter OsPT6, which was induced by P deficiency, suggesting that NaCl also facilitated the P translocation prominently from root to shoot in P starved rice. Moreover, exogenous abscisic acid (ABA) can reverse the NaCl-mediated mitigation under P deficiency, indicating the involvement of ABA in the NaCl regulated root cell wall P reutilization. Taken together, our results demonstrated that NaCl can activate the reutilization of root cell wall P in P starved rice, which is dependent on the ABA accumulation pathway.

In order to improve the activity of Pd catalyst for methanol catalytic oxidation, carbon fiber cloth was prepared by pre-oxidizing PAN/CA fiber cloth and heat-treated at 1 200 ℃, and the surface was loaded with different content of Pd. The microscopic structure of CNFs/Pd catalyst sample and performance testing were analyzed to find the effect of Pd catalyst. The results showed that the performance of the catalyst for electrocatalytic oxidation of methanol increased firstly and then decreased with the concentration increase of the PdCl2 solution. When the concentration of the PdCl2 solution was 0.02 mol/L, the catalyst performance was the best, and its performance and stability were about 3.3 and 10 times of the commercial Pd/C catalyst. Compared with the commercial catalyst, the activity and stability are both improved.

Conjugated diene molecules are highly reactive upon photoexcitation and can relax through multiple reaction channels that depend on the position of the double bonds and the degree of molecular rigidity. Understanding the photoinduced dynamics of these molecules is crucial for establishing general rules governing the relaxation and product formation. Here, we investigate the femtosecond time-resolved photoinduced excited-state structural dynamics of cis,cis-1,3-cyclooctadiene, a large-flexible cyclic conjugated diene molecule, upon excitation with 200 nm using mega-electron-volt ultrafast electron diffraction and trajectory surface hopping dynamics simulations. We tracked the photoinduced structural changes from the Franck–Condon region through the conical intersection seam to the ground state. Our findings revealed a novel primary reaction coordinate involving ring distortion, where the ring stretches along one axis and compresses along the perpendicular axis. The nuclear wavepacket remains compact along this reaction coordinate until it reaches the conical intersection seam, and it rapidly spreads as it approaches the ground state, where multiple products are formed. [ABSTRACT FROM AUTHOR]

The effectiveness of chlorine dioxide as a soil disinfectant for the prevention and control of apple replant disease (ARD) remains largely unexplored. This study aimed to determine the optimal concentration of chlorine dioxide for soil disinfection and to evaluate its impact on the prevention and control of ARD. The experimental results indicated that a high concentration of 600 mg·L−1 chlorine dioxide exhibited a potent lethal effect on both the hyphae and spores of pathogenic Fusarium. Results from pot experiments demonstrated that, compared with the replant control, the height, ground diameter, fresh weight, and dry weight of Malus hupehensis Rehd. seedlings treated with 600 mg·L−1 chlorine dioxide increased by 27.20%, 15.95%, 100.70%, and 76.28%, respectively. Additionally, the root length, surface area, volume, and number of root tips of the seedlings increased by 31.74%, 96.54%, 257.29%, and 85.29%, respectively. The activities of root-protective enzymes, including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), also increased to varying degrees, whereas the malondialdehyde (MDA) content was significantly reduced compared with the control treatment. Furthermore, the number of soil fungi treated with chlorine dioxide and the concentration of phenolic acid compounds in replant soil were significantly reduced. Treatment with 600 mg·L−1 chlorine dioxide significantly decreased the detected copy number of genes associated with soil-borne pathogenic Fusarium, optimized the soil microbial community structure, and reduced the relative abundance of pathogenic fungi. In summary, disinfection of replant soil using 600 mg·L−1 chlorine dioxide can enhance the growth of M. hupehensis Rehd. seedlings, inhibit the growth and reproduction of pathogenic Fusarium fungi, improve the soil environment, and effectively prevent and control ARD. [ABSTRACT FROM AUTHOR]

In the final assembly stage of military aircraft,there are problems of high control cost caused by the disconnection between quality control and business process and the lack of advanced quality planning. To solve these problems,insufficient quality planning and high control costs in the military aircraft final assembly stage,APQP(Advanced Product Quality Planning)application guide suitable for the military aircraft final assembly stage is proposed by improving the APQP guidance material of the IAQG(International Aerospace Quality Group),including theoretical models,core content and key elements,etc. The application effect of the military aircraft assembly APQP in process optimization and management,risk identification and control are verified on the aero-engine installation. The results show that the military aircraft assembly APQP is beneficial to predict and reduce risks,reduce process changes,improve military aircraft quality and delivery efficiency.

Three-dimensional (3D) network topological structure composite (3D-NTSC) is a new type of composite in which both the matrix phase and the reinforced phase have 3D continuous network structure and interweave with each other. Different from fiber reinforcement and particle reinforcement, the reinforcing phase in the composite material runs through the whole matrix phase in a continuous form without destroying the topological continuity of the matrix phase, so that each matrix phase in the composite material can not only maintain its own excellent performance, but also can cooperate with each other and complement each other, so that the composite material can play a greater performance advantage. In recent years, 3D-NTSC has attracted the attention of researchers and has been widely used in practical production. At present, there are no comprehensive articles summarizing the research progress of this kind of materials. In this review, we discussed the recent progress of the preparation methods, including natural flow method, vacuum infiltration process, pressure filling method, in situ filling method, and co-building method. Furthermore, research progress on mechanical properties and some regular results, shortcomings, challenges, and prospects of 3D-NTSC were also put forward, which would be helpful to people working in the related fields.

The VCPIP1‐P97/VCP (Valosin‐Containing Protein) complex is required for post‐mitotic Golgi cisternae reassembly and maintenance in interphase. However, the organization and mechanism of this complex in regulating Golgi membrane fusion is still elusive. Here, the cryo‐electron microscopy (cryo‐EM) structures of the human VCPIP1‐P97/VCP complex are presented. These studies reveal that three independent VCPIP1 molecules sit over the C‐terminal substrate exit tunnel formed by P97/VCP homo‐hexamer, resulting in an unusual C3 to C6 symmetric barrel architecture. The UFD1 (unknown function domain 1) from VCPIP1, but not the N‐terminal OTU domain and the C‐terminal UBL domain, docks to the two adjacent D2 domains of P97/VCP, allosterically causing the cofactors binding domain‐NTDs (N‐terminal domains) of P97/VCP in a "UP" and D1 domain in an ATPase competent conformation. Conversely, VCPIP1 bound P97/VCP hexamer favors the binding of P47, and thus the intact SNARE complex, promoting Golgi membrane fusion. These studies not only reveal the unexpected organization of humanVCPIP1‐P97/VCP complex, but also provide new insights into the mechanism of VCPIP1‐P97/VCP mediated Golgi apparatus reassembly, which is a fundamental cellular event for protein and lipid processing. [ABSTRACT FROM AUTHOR]

The crude metabolic extract from plant biocontrol bacteria plays a very important role in sustainable agricultural production. These extracts help maintain healthy plants and have very important application prospects in biotechnology related to alleviating apple replant disease (ARD). In this study, Bacillus velezensis XC1 (T1), Bacillus amyloliquefaciens QSB-6 (T2), and Lactobacillus reuteri LBR (T3) were examined to characterize the ability of their crude metabolic extracts to alleviate ARD. The high-throughput sequencing data of the soil microbial community structure were analyzed in relation to LBR crude metabolic extracts, and an extensive untargeted metabolomic analysis of UHPLC-Qex active components was performed. Active LC-MS/MS revealed that the main secondary metabolites involved in the biological control exerted by L. reuteri included 3-hydroxypropionaldehyde, extracellular polysaccharides (EPS), p-hydroxybenzoic acid, and azelaic acid. These crude metabolic extracts significantly inhibited the growth of soil pathogenic fungi, reduced the abundance of Fusarium, promoted the abundance of beneficial bacteria such as Pseudomonas, and optimized the soil microbial community structure. Improved modern extraction and purification technologies will be able to offer additional insights into the mechanism of action of these secondary metabolites and enable them to be used in biological preparations to prevent and control ARD in the future, as well as to allow harmful chemical fumigants to be discontinued. [ABSTRACT FROM AUTHOR]

When using a wrench, the nut is easily damaged due to improper operation or impact. Although coating a polymer layer on the surface of the wrench can effectively solve the above problem, the layer is easy to be deboned due to the lack of adhesion between the polymer and the surface of the wrench. Herein, we implemented an anodizing treatment strategy on the surface of the wrench to obtain a porous oxide film. Interestingly, during the anodization process, micro-nanopores with a specific diameter can be obtained by adjusting the voltage, temperature, and electrolyte concentration. Furthermore, the ammonium fluoride/ethylene glycol electrolyte was used to etch the formed large hole to form the large hole sleeve small hole structure. In order to inject polyphenylene sulfide (PPS) molecules into multiscale holes to form a pinning effect, we also used nano molding technology to inject PPS into the metal surface. The results showed that the adhesion between PPS and the wrench was greatly improved compared with the commonly used dip coating method.