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A new strategy for facile access to multifunctionalized furans via N-heterocyclic carbene-catalyzed cross-coupling/cyclization of ynenones with aldehydes has been explored. This protocol features readily obtainable starting materials, mild and metal-free conditions, broad substrate scope, good functional group tolerance, excellent yields, and easy scale-up. Synthetic utility of the protocol has been further corroborated through functionalization of complex substrates and postmodifications of the product.

Purpose: This paper considers the air gap tracking problem of the levitation control system for medium and low-speed maglev vehicles subject to magnetic nonlinearities and track irregularities. Method: The static and dynamic magnetic field characteristics are investigated, and an improved electromagnetic force model to consider both the magnetic saturation and eddy current effect is developed. By merging neural networks (NNs), a robust adaptive control scheme is proposed, which can deal with the modeling uncertainties and magnetic nonlinearities without requiring precise model information, leading to enhanced levitation performance from the aspects of suspension safety and ride comfort. Based on the Lyapunov method, the continuity of the control signal and uniformly ultimately boundedness(UUB) of all closed-loop signals can be guaranteed. Results and conclusion: With the dynamic model of the whole suspension bogie and random irregularities, numerical simulations under various operation conditions, including constant speed, horizontal curve and vertical curve, validating the developed control scheme improves the suspension safety while maintaining the ride comfortability for passengers.

A rhodium-catalyzed carbene N–H insertion protocol for simultaneously controlling the C–N axial and spiro-central chiralities is disclosed, resulting in the rapid assembly of enantiopure N-arylindolinone-spiroacetal derivatives in high yields with excellent enantioselectivities. This promising strategy features the chiral C–N axis, spiro-central chirality, functional group tolerance, and late-stage diversification. DFT calculations indicate that the N–H insertion is the axial-chirality-determining step and that the 1,5-H shift step is regiospecifically caused by the spirocycle.

The vehicle stability region can be used to evaluate vehicle stability performance and lay the foundation for vehicle safety improvement. It can be obtained via the region of attraction (RoA) based on sums of squares (SOS) programming. However, it is usually conservative, and the computational burden is large. This article focuses on the above issues and proposes a well-developed method for RoA estimation, with application to the estimation and expansion of the vehicle stability region. For RoA estimation, an improved SOS program is formulated, and its optimization objective combined with the customized algorithm significantly reduces conservatism. In addition, the feasibility prejudgment strategy and the dynamic search range are proposed in the algorithm. As a result, the computational burden is greatly reduced, which also indirectly helps reduce conservatism. Then, a more accurate vehicle stability region is obtained with less time consumption, and a map-based controller is proposed to improve vehicle stability. Better stability performance and larger stability regions are guaranteed under different scenarios due to the adaptive adjustment of controller gains. Finally, simulations and hardware-in-the-loop experiments with an embedded vehicle controller are performed to verify the effectiveness of our method.

Multivalent interaction is often used in molecular design and leads to engineered multivalent ligands with increased binding avidities toward target molecules. The resulting binding avidity relies critically on the rigid scaffold that joins multiple ligands as the scaffold controls the relative spatial positions and orientations toward target molecules. Currently, no general design rules exist to construct a simple and rigid DNA scaffold for properly joining multiple ligands. Herein, we report a crystal structure-guided strategy for the rational design of a rigid bivalent aptamer with precise control over spatial separation and orientation. Such a pre-organization allows the two aptamer moieties simultaneously to bind to the target protein at their native conformations. The bivalent aptamer binding has been extensively characterized, and an enhanced binding has been clearly observed. This strategy, we believe, could potentially be generally applicable to design multivalent aptamers.

A novel and straightforward strategy for the construction of versatile densely functionalized aryl α‐keto esters is disclosed through a one‐pot and efficient [4+2] benzannulation reaction of α‐cyano‐β‐methylenones and ynediones, which could be synthesized easily from the corresponding starting materials. This protocol features high yield, mild metal‐free reaction condition, high atom economy, high functional‐group tolerance, easy handing and gram‐scale synthesis. An effective approach to constructdensely functionalized aryl α‐keto esters under mild conditions has been reported. A broad range of multi‐substituted benzenes were prepared in good to excellent yields and many useful functional groups could be tolerated.

•Aspirin (ASP) or verapamil (VPL) may be a sensitiser for caspofungin (CAS).•Antifungal effects of CAS may be sensitised by ASP or VPL under planktonic and biofilm conditions.•These findings provide a reliable basis for clinical treatment of C. albicansinfections with CAS combined with ASP or VPL.

Antibiotics play an irreplaceable role in the prevention and treatment of bacterial infection diseases. However, because of the improper use of antibiotics, bacterial resistance emerges as a major challenge of public health all over the world. The small thiol molecules such as glutathione can directly react and conjugate with some antibiotics, which thus contribute to drug susceptibility and resistance. Recently, accumulating evidence shows that there is a close link between the antibacterial activities of some antibiotics and Reactive Oxygen Species (ROS). Thioredoxin and glutathione systems are two main cellular disulfide reductase systems maintaining cellular ROS level. Therefore, these two thioldependent antioxidant systems may affect the antibiotic susceptibility and resistance. Microorganisms are equipped with different thiol-dependent antioxidant systems, which make the role of thioldependent antioxidant systems in antibiotic susceptibility and resistance is different in various bacteria. Here we will focus on the review on the advances of the effects of thiol-dependent antioxidant system in the bacterial antibiotic susceptibility and resistance.

Acute alcoholism often induces lesions in multiple organs. There is currently no specific treatment for acute alcoholism in clinical practice. Few people know the anti-alcoholic effect of myricetin (MYR). It is known to have some potential to combat alcoholism based on our preliminary experiments. Additionally, its poor water solubility limits its efficacy. The purpose of this study is to enhance the anti-alcoholic effect by improving the solubility using Kolliphor ® HS15 to prepare supramolecular aggregates of MYR (MYR-SA). The solubility of MYR-SA in water was increased more than 1785-fold. Due to p-gp inhibition by HS15, the Ka and Peff of MYR-SA were about 10-fold higher than pure MYR, respectively, assayed in the intestinal perfusion model. Pharmacokinetic revealed that the AUC0-tof MYR-SA was 2.17-fold higher than that of MYR. Upon administration of MYR-SA in intoxicated animals, the highest blood alcohol level was significantly decreased by 44.9%, the onset of LORR (Loss of righting reflex) was prominently prolonged 3.13-fold. In addition, MYR-SA significantly increased the enzymatic activities of ADH and ALDH in mice (p < 0.01). MYR-SA dramatically reduced oxidative stress and protected mouse gastric mucosa from ethanol-stimulated injury. In summary, MYR-SA showed excellent performance in counteracting alcoholism by improving the oral bioavailability of MYR greatly.

In order to solve comprehensive decision problem which exist in power grid planning, Analytic hierarchy process (AHP) is applied to distribution network planning is put forward to the selection of alternatives. Based on the actual case, Established hierarchical structure model and the attributes decision table, Form a judgment matrix one by one, then Calculate the synthesis weights and achieve the decision results.The results show that analytic hierarchy process can better combining expert experience and quantitative calculation, It is very well Solution to the comprehensive evaluation of the distribution network planning decisions. It is a practical solution of distribution network planning.

Easy to assemble!An enantioselective cascade Mannich intramolecular ring cyclization–tautomerization reaction of malononitrile with 2‐hydroxyl N‐protected α‐amido sulfone is described (see scheme), which provides a new route to the synthesis of the privileged scaffold 2‐amino‐4H‐chromene in high yields (up to 94 %) and with good to high enantiomeric excesses (74–89 % ee).

A surprising exampleof enantioselective cascade Michael–oxa‐Michael–tautomerization reactions of malononitrile and benzylidenechromanones has been developed. In this case, malononitrile functions as both nucleophile and electrophile. Meanwhile, a simple bifunctional indane amine–thiourea catalyst has been discovered to promote this process to afford high yields (up to 99%) and high to excellent enantiomeric excesses (81–99% ee).

Efficient excess: An efficient and facile enantioselective Michael addition reaction through hydrogen‐bonding catalysis for the synthesis of coumarin complexes has been developed (see scheme). A simple bifunctional amine–thiourea small molecule has been discovered to catalyze this process with high yields and high to excellent enantiomeric excesses.

Ninety-five subjects aged 60 years and over underwent casual and ambulatory blood pressure (BP) measurements as well as weight, height, both waist and hip circumferences and both upper arm and thigh circumferences. Most anthropometric variables were significantly correlated with measures of BP. One stepwise regression analysis was applied to reveal that among measures of BP, 24-hour systolic BP had the strongest correlation with waist/hip ratio and awaking diastolic BP the strongest correlation with weight, both waist and hip circumferences and body mass index. Another was used to show that waist/hip ratio was the best overall predictor of systolic BP and weight the best overall predictor of diastolic BP. We suggest

The cascade Michael addition—enolization—cyclization reaction of β,γ‐unsaturated α‐ketoesters (I) and (IV) with cyclohexanedione (II) is smoothly catalyzed by a novel bifunctional tertiary amine—thiourea organocatalyst to give highly functionalized hexahydrobenzopyranones (III) and (V), resp., in high enantioselectivity.

The medicinally important skeleton is catalyzed by a new indan organocatalyst IAT bearing amine and thiourea moieties.

It is found that the thiourea efficiently promotes asymmetric Michael‐hemiketalization of the naphthoquinone (I) yielding benzochromenes of type (III) with excellent enantioselectivity.

With the object to obtaining novel biologically active spiro chromanones the domino reaction of benzylidene‐chromanones (I) and 2‐mercapto‐benzaldehydes (II) is accomplished in the presence of a chiral indane amino‐thiourea catalyst.

The reaction is catalyzed by a new bifunctional indan amine‐thiourea compound to afford optically active pyranochromenes in high yields and enantioselectivities.