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This study introduces a novel approach for synthesizing Benzoxazine‐centered Polychiral Polyheterocycles (BPCPHCs) via an innovative asymmetric carbene‐alkyne metathesis‐triggered cascade. Overcoming challenges associated with intricate stereochemistry and multiple chiral centers, the catalytic asymmetric Carbene Alkyne Metathesis‐mediated Cascade (CAMC) is employed using dirhodium catalyst/Brønsted acid co‐catalysis, ensuring precise stereo control as validated by X‐ray crystallography. Systematic substrate scope evaluation establishes exceptional diastereo‐ and enantioselectivities, creating a unique library of BPCPHCs. Pharmacological exploration identifies twelve BPCPHCs as potent Nav ion channel blockers, notably compound 8 g. In vivo studies demonstrate that intrathecal injection of 8 g effectively reverses mechanical hyperalgesia associated with chemotherapy‐induced peripheral neuropathy (CIPN), suggesting a promising therapeutic avenue. Electrophysiological investigations unveil the inhibitory effects of 8 g on Nav1.7 currents. Molecular docking, dynamics simulations and surface plasmon resonance (SPR) assay provide insights into the stable complex formation and favorable binding free energy of 8 g with C5aR1. This research represents a significant advancement in asymmetric CAMC for BPCPHCs and unveils BPCPHC 8 g as a promising, uniquely acting pain blocker, establishing a C5aR1‐Nav1.7 connection in the context of CIPN. [ABSTRACT FROM AUTHOR]

This study introduces a novel approach for synthesizing Benzoxazine‐centered Polychiral Polyheterocycles (BPCPHCs) via an innovative asymmetric carbene‐alkyne metathesis‐triggered cascade. Overcoming challenges associated with intricate stereochemistry and multiple chiral centers, the catalytic asymmetric Carbene Alkyne Metathesis‐mediated Cascade (CAMC) is employed using dirhodium catalyst/Brønsted acid co‐catalysis, ensuring precise stereo control as validated by X‐ray crystallography. Systematic substrate scope evaluation establishes exceptional diastereo‐ and enantioselectivities, creating a unique library of BPCPHCs. Pharmacological exploration identifies twelve BPCPHCs as potent Nav ion channel blockers, notably compound 8 g. In vivo studies demonstrate that intrathecal injection of 8 g effectively reverses mechanical hyperalgesia associated with chemotherapy‐induced peripheral neuropathy (CIPN), suggesting a promising therapeutic avenue. Electrophysiological investigations unveil the inhibitory effects of 8 g on Nav1.7 currents. Molecular docking, dynamics simulations and surface plasmon resonance (SPR) assay provide insights into the stable complex formation and favorable binding free energy of 8 g with C5aR1. This research represents a significant advancement in asymmetric CAMC for BPCPHCs and unveils BPCPHC 8 g as a promising, uniquely acting pain blocker, establishing a C5aR1‐Nav1.7 connection in the context of CIPN. [ABSTRACT FROM AUTHOR]

High penetration of uncertain wind power generation brings challenges to power system operational security and economy. Here, an adjustable box uncertainty set is first presented to characterize the spatiotemporal correlation of multiple wind power generations. Afterward, a two‐stage risk‐adjusted robust energy dispatching model is established as a min‐max‐min optimization problem for active distribution networks operating with high penetration wind power generation. Then a three‐layer Nest Column and Constraint Generation (NCCG) decomposition approach is designed to efficiently solve the proposed model. Finally, the proposed two‐stage adaptive robust optimization model and NCCG approach are validated by a distribution network with uncertain wind power generations, and the simulation results indicate the distribution network operation economy could be compromised with robustness by adjusting the conservative regulation parameter. [ABSTRACT FROM AUTHOR]

How to improve the efficiency of bag filters has attracted a considerable amount of attention. However, effective control of the transition stage, which plays an important role in reducing the time to reach a new steady state, still lacks research. Here, we utilize a nominal linear system with a time delay to characterize the transition stage. We introduce two state feedback mechanisms, namely linear matrix inequality based state-feedback robust controller and parameter-tuning controller based on nonlinear matrix inequality, into control process. Results of both genetic algorithms simulations and closed-loop control experiments show that these controllers dramatically shorten the transition stage compared to open-loop control. Furthermore, we find that parameter-tuning controller outperforms linear matrix inequality based state-feedback robust controller in terms of both stable time and steady error. These results are robust to different experimental settings. From industrial economic perspective, this technology could help to conserve energy and protect environment. [ABSTRACT FROM AUTHOR]

Metallaphotocatalysis has been recognized as a pivotal catalysis enabling new reactivities. Traditional metallaphotocatalysis often requires two or more separate catalysts and exhibits flaw in cost and substrate-tolerance, thus representing an await-to-solve issue in catalysis. We herein realize metallaphotocatalysis with a bifunctional dirhodium tetracarboxylate ([Rh2]) alone. The [Rh2] shows an photocatalytic activity of promoting singlet oxygen (1O2) oxidation. By harnessing its photocatalytic activity, the [Rh2] catalyzes a photochemical cascade reaction (PCR) via combination of carbenoid chemistry and 1O2 chemistry. The PCR is characterized by high atom-efficiency, excellent stereoselectivities, mild conditions, scalable synthesis, and pharmaceutically interesting products. DFT calculations-aided mechanistic study rationalizes the reaction pathway and interprets the origin of stereoselectivities of the PCR. The products show inhibitory activity against PTP1B, being promising in the treatment of type II diabetes and cancers. Overall, here we show the bifunctional [Rh2] merges Rh-carbenoid chemistry and 1O2 chemistry. Traditional metallaphotocatalysis often requires two or more separate catalysts and is considered to be costly and not tolerant towards a wide substrate scope. Here the authors realize metallaphotocatalysis with a bifunctional dirhodium tetracarboxylate as single catalyst component to merge carbenoid chemistry and 1O2 chemistry. [ABSTRACT FROM AUTHOR]

The problem of source number estimation was a key issue in blind source separation (BSS), because the number of sources directly affected the effect of BSS. To solve this problem, this study proposed a single-channel blind source number estimation algorithm that took the information entropy as the statistical evaluation index, and used the information entropy to measure the information quantity of the source signal to determine the source number. To calculate the information entropy of the estimated source signals, firstly, the Gaussian mixture model (GMM) was used to fit their distributions. Secondly, samples obeying the target distribution were sampled and the entropy was calculated based on the Markov chain Monte Carlo (MCMC) algorithm. Finally, the source number was obtained by minimizing the average information entropy of the source signal. A series of experiments based on simulation data and real communication data showed that the proposed algorithm had strong robustness and could estimate the number of sources with 94% accuracy, thus verifying the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

The stator structure is one of the main factors affecting the electromagnetic performance of permanent magnet (PM) motors. In this paper, an in-depth study and analysis of how to reduce the cogging torque is carried out from the perspective of the stator structure. According to the theory of cogging torque synthesis, this paper presents a unified calculation formula for different PM motor skewed notch designs. This theory is verified with a 20-pole, 60-slot motor and a 20-pole, 24-slot motor, respectively. The formula worked out proved to be highly applicable. The formula is intended to address how to quickly obtain key data (skew angle, notch depth) in a skewed notch study. [ABSTRACT FROM AUTHOR]

This article proposes that the problem of pastoral irony (as formulated in Harry Berger's seminal article on strong and weak pastoral) and the nature of ekphrasis are both clarified if they are understood as expressions of the desire for an escape from meaningful, signifying language and into the materiality of objects. Drawing on responses to Theocritus, readings of ekphrasis, and philosophical interpretations of the boundary between words and things, I argue that pastoral irony represents an initial moment of escape from signification, and ekphrasis a final moment of representing objects, mediated by a paradoxical object representing the negation of meaning. [ABSTRACT FROM AUTHOR]

To address the issues of ignition difficulty, incomplete burnout, and high NOx emissions during coal char combustion in industrial applications, a series of co-firing experiments involving bituminous coal and its medium-temperature pyrolysis char were conducted using a micro fluidized bed analysis system. The experiments explored co-firing behaviors and NOx emission characteristics for five different fuel blending ratios in an environment with 21 % oxygen concentration, across temperatures between 923 K and 1223 K. The study delved into the synergistic effects of coal and char co-firing, as well as the influence of combustion temperature and fuel blend ratio on the co-firing efficiency and NOx emissions. The results show a synergistic effect in the co-firing of bituminous coal and char, influenced by reaction temperature and coal-to-char blend ratio, which evolves as combustion progresses. In the 923–1073 K range, initial coal addition to the blend enhances reactivity. However, as the reaction advances or coal content exceeds 75 %, this synergy shifts to an inhibitory effect. At temperatures above 1023 K, increased proportions of coal in the blend are associated with improved burnout rates, especially when the coal content is at or above 50 %. Moreover, at a combustion temperature of 1123K, there is a marked decrease in nitrogen oxide emissions, with coal blend ratio of 25 % and 50 % showing particular efficacy in reducing these emissions. These results provide valuable insights for the efficient and clean utilization of coal char in industrial combustion processes. • The synergistic effect of co-firing depends on the temperature and the blend ratio, and changes with the reaction process. • Between 923 and 1073K, bituminous coal initially enhances fuel reactivity but later or above 75 % content, it hinders the reaction. • Temperatures over 1023 K combined with coal contents at or exceeding 50 % lead to increased burnout rates. • NOx emissions attain lowest value at 1123 K, with coal proportions of 25 % and 50 %. [ABSTRACT FROM AUTHOR]

The article focuses on the poet Theocritus and his readers who take interest in fictional pastoral world. Topics discussed include conceive of the experience related to painting, pastoral, and objects, the presence of fictional beings, and relation of fictional world and readers and poem's representation in fictional world.

In this paper, we design an L-shaped MEMS microspring. The formula for the spring constant and the stress distribution of the microspring are worked out in theory, which are proved correctly by FEM (Finite element method) simulation. Four L-shaped microsprings named as #1, #2, #3, #4 with different dimensions are fabricated. The tensile experiment and FEM also show that the fractured positions are all located in the corner of the microspring. And each stage of deformation of the microspring is the same, which is proved by the image captured by CCD during the tensile experiment. When the microspring is applied to a shock load, the upper end of the microspring has a much larger deformation than others, which is different from that of the static load. It offers reference for latter MEMS microspring design. [ABSTRACT FROM AUTHOR]

Permanent magnet couplings can convert a dynamic seal into a static seal, thereby greatly improving the stability of the underwater propulsion unit. In order to make full use of the tail space and improve the transmitted torque capability, a conical Halbach permanent magnet coupling (C-HPMC) is proposed in this paper. The C-HPMC combines multiple cylindrical HPMCs with different sizes into an approximately conical structure. Compared with the conical permanent magnet couplings in our previous work, the novel C-HPMC has better torque performance and is easy to process. The analytical calculation method of transmitted torque of C-HPMC is proposed on the basis of torque calculation of the three common types of HPMCs. The accuracy of the torque calculation of the three HPMCs is verified, and the torque performance of the three HPMCSs of different sizes is compared and discussed. The "optimal type selection" method is proposed and applied in the design of C-HPMC. Finally, on the basis of torque analysis calculation and axial force calculation, a complete flowchart of the design and performance analysis of C-HPMC is described. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) is one of the most common types of the cardiovascular disease. Previous pilot trials have suggested that Traditional Chinese Medicine (TCM) has brought clinical benefits for patients with CAD. We will conduct this trial to determine the efficacy and safety of Shenzhu Guanxin Recipe Granules (SGR) for the treatment of patients with CAD.Methods: This randomized controlled trial recruited 190 patients who were diagnosed with CAD by clinical manifestation and examination and in which coronary computed tomography angiography (CCTA) showed 50-70% stenosis, with soft or mixed plaque types. The included participants were randomly assigned to the case group and control group using a 1:1 allocation ratio; patients in the case group received SGR and usual care, and those in the control group received placebo (6 g/day for 6 months) and usual care. The endpoint of the study included Calcium Coverage Score (CCS), C-reactive protein (CRP) level, and the levels of blood lipids, tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), and ATP-binding membrane cassette transporter A1 (ABCA1) were calculated before recruiting and at the sixth month. The indicators were Seattle Angina Questionnaire (SAQ) and TCM Syndrome Questionnaire scores at 0, 3, and 6 months.Discussion: This clinical trial may provide reliable evidence regarding the clinical effectiveness and safety of SGR therapy for patients with CAD diagnosed by clinical manifestation and examination, in which CCTA showed 50-70% stenosis, with soft or mixed plaque types.Trial Registration: ClinicalTrials.gov, ID: ChiCTR1900020501 . The trial was registered on 25 December 2018. [ABSTRACT FROM AUTHOR]

How to reduce the cogging torque of the integrated propeller motor is an important means to improve its noise performance because cogging torque is one of the key factors causing torque ripple. We proposed a method to reduce the cogging torque by optimizing the size of the Halbach array's auxiliary pole. First, an analytical model for the airgap magnetic field of Halbach array based on different dimensions (including the circumference ratio and the radial thickness) of the auxiliary pole is given. Then the finite element method is used to verify the analytical model. On the basis, we calculated the cogging torque of different size of auxiliary poles as sample data by combining different circumference ratio and radial thickness. Furthermore, using the two-variable single-objective neural network genetic optimization algorithm based on Backpropagation (BP), we obtain the optimal size of the auxiliary pole. Finally, comparing the motor cogging torque and torque ripple before and after optimization indicated that the cogging torque and torque ripple are effectively reduced after optimizing the size of the auxiliary pole. [ABSTRACT FROM AUTHOR]

Permanent magnet couplings (PMCs) are widely used in underwater propulsion because it can solve the deep-sea sealing problem effectively. In this paper, a new type of conical permanent magnet coupling (CPMC) is proposed, which is able to match the tail shape of the underwater vehicle and make full use of the tail space to increase pull-out torque capability. Based on the three-dimensional finite element method (3D-FEM), the electromagnetic characteristics of an initial model for CPMC are analyzed. In order to facilitate the design and optimization of CPMC, an equivalent three-dimensional (3D) analytical method for the pull-out torque calculation is presented, and its accuracy is verified by comparison with the 3D finite element results. Finally, the influence of design parameters such as half-cone angle, pole pair, pole arc coefficient and permanent magnet thickness on maximum pull-out torque and torque density of CPMC is analyzed, and a preliminary optimization model is obtained. [ABSTRACT FROM AUTHOR]