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Flight load analysis is a complex and arduous task, and developing a fast analysis method during the conceptual design stage is of great importance to improve the efficiency of flight load calculation. Based on the small disturbance linear analysis theory, the theoretical calculation methods of wing-body aerodynamic load, horizontal tail aerodynamic load, vertical tail aerodynamic load, control surface hinge moment, and the engineering calculation methods of aerodynamic load distribution, inertial load distribution, shear and bending moment of lift surface are summarized. This is a simplified calculation method of flight load. A mathematical model of a certain single seat competitive aircraft is established in the Matlab environment, taking the configuration dimension, mass characteristics and aerodynamic derivative as inputs, the response process of aerodynamic load, inertial load, control surface hinge moment, shear and bending moment are obtained. The results show that the simplified method can quickly get the dynamic parameters with less input data, and the calculation results can be used to satisfy the load requirements of structural design in the conceptual design stage.

Compared to common salt, low-sodium salt can reduce blood pressure to varying degrees. However, the exact dosage relationship remains unclear. We aimed to investigate the dose–response relationships between low-sodium salt intake and systolic blood pressure (SBP) and diastolic blood pressure (DBP), as well as the risk of hypertension, and to determine the optimal range for low-sodium salt intake. We investigated the basic characteristics and dietary profile of 350 individuals who consumed low-sodium salt. The samples were divided into three groups according to the 33.3rd and 66.6th percentiles of low-sodium salt intake in condiments (Q1: <4.72 g/d, Q2: ≥4.72 g/d, and <6.88 g/d, and Q3: ≥6.88 g/d). The restricted cubic spline results indicated that low-sodium salt intake decreased linearly with SBP and DBP, while low-sodium intake demonstrated a non-linear, L-shaped relationship with the risk of hypertension, with a safe range of 5.81 g to 7.66 g. The multiple linear regression analysis revealed that compared with group Q1, the DBP in group Q2 decreased by 2.843 mmHg (95%CI: −5.552, −0.133), and the SBP in group Q3 decreased by 4.997 mmHg (95%CI: −9.136, −0.858). Exploratory subgroup analyses indicated that low-sodium salt intake had a significant impact on reducing SBP in males, DBP in females, SBP in rural populations, and DBP in urban populations. The intake of low-sodium salt adheres to the principle of moderation, with 5.81–7.66 g potentially serving as a pivotal threshold. [ABSTRACT FROM AUTHOR]

Under-deposit corrosion is widely present in the pipelines of oil and gas production, causing significant corrosion damage. In this paper, a novel electrochemical cathodic-polarization method was carried out to accelerate the formation of CaCO3 scale on a X65 steel surface in a simulated solution containing scaling ions. Subsequently, pre-scaled X65 steel was placed in a high temperature and pressure autoclave to conduct corrosion weight-loss experiments and in situ electrochemical measurements. The study mainly compared the corrosion inhibition behavior of four quaternary ammonium salt corrosion inhibitors, pyridinium quaternary salt (BPC), quinolinium quaternary salt (BQC), 8-hydroxyquinolinium quaternary salt (BHQ) and pyridinium (1-chloromethyl naphthalene) quaternary salt (1-CPN), in a simulated oilfield scale under corrosive conditions. The results of the weight-loss experiments demonstrated that the inhibition efficiencies of the corrosion inhibitors from high to low were as follows: 1-CPN < BHQ < BQC < BPC. The in situ electrochemical measurements showed that the immersion time and type of corrosion inhibitor had a pronounced influence on the corrosion and corrosion inhibition behavior of X65 steel with CaCO3 coating. It was also proved using both EIS and PC that 1-CPN shows the best inhibition performance in all. Lastly, the inhibition mechanism of corrosion inhibitors at under-deposit conditions was analyzed via a surface morphology observation of SEM. [ABSTRACT FROM AUTHOR]

With the development of the times and policies, vocational education has received more and more attention; Combining the issues focused on in international teaching, expanding new teaching ideas, emphasizing the integration of theory with practice, and improving teachers’ professional English abilities. At the same time, continuously enrich multimedia teaching methods, strengthen diversified assessment methods, continuously improve teaching methods, promote the construction of teaching teams, and further improve the quality of vocational education.

Plenty of metal sulfides have been employed as electrocatalysts to accelerate sluggish redox reaction kinetics and inhibit the annoying shuttle effect of lithium polysulfides (LiPSs) for lithium–sulfur (Li–S) batteries. Nevertheless, the activity of these catalysts is restricted by the limited number of active sites and poor electrical conductivity, resulting in disappointing cycling performance and rate stability. Herein, CoS2/MoS2 heterostructures anchored on carbon nanotubes (denoted as CoS2–MoS2/CNT) are fabricated by a facile hydrothermal method combined with a vulcanization process, and they serve as a multifunctional interlayer on a PP separator for Li–S batteries to solve the above problems. A series of systematic experiments and in situ spectroscopy elucidate that the interfacial interaction in the CoS2–MoS2 heterojunction not only activates Co sites in favor of anchoring LiPSs and inhibiting the shuttle effect but also synchronously induces the phase transformation of MoS2 from semi-conductive 2H to metallic 1T, and the ample yield of basal and edge defects contributes to the rapid catalytic kinetics of sulfur species. Consequently, a Li–S battery decorated with a CoS2–MoS2/CNT separator delivers a sparkling initial capacity of 921.8 mA h g−1 at 2C with a degradation rate of only 0.036% per cycle over 1000 cycles. This study provides novel insights for interfacial engineering and defect chemistry in durable Li–S electrochemistry and provides a prospective strategy for rational electrocatalyst designs with regard to the diverse energy-storage realm. [ABSTRACT FROM AUTHOR]

Pancreatic β-cell failure is a pathological feature in type 1 diabetes. One promising approach involves inducing transdifferentiation of related pancreatic cell types, specifically α cells that produce glucagon. The chemokine stromal cell-derived factor-1 alpha (SDF-1α) is implicated in pancreatic α-to-β like cell transition. Here, the serum level of SDF-1α was lower in T1D with C-peptide loss, the miR-23a was negatively correlated with SDF-1α. We discovered that exosomal miR-23a, secreted from β cells, functionally downregulates the expression of SDF-1α, leading to increased Pax4 expression and decreased Arx expression in vivo. Adenovirus-vectored miR-23a sponge and mimic were constructed to further explored the miR-23a on pancreatic α-to-β like cell transition in vitro, which yielded results consistent with our cell-based assays. Suppression of miR-23a upregulated insulin level and downregulated glucagon level in STZ-induced diabetes mice models, effectively promoting α-to-β like cell transition. Our findings highlight miR-23a as a new therapeutic target for regenerating pancreatic β cells from α cells. [ABSTRACT FROM AUTHOR]