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At present, cardiovascular disease is one of the important factors of human death, and there are many kinds of proteins involved. Sirtuins family proteins are involved in various physiological and pathological activities of the human body. Among them, there are more and more studies on the relationship between sirtuin2 (SIRT2) protein and cardiovascular diseases. SIRT2 can effectively inhibit pathological cardiac hypertrophy. The effect of SIRT2 on ischaemia‐reperfusion injury has different effects under different conditions. SIRT2 can reduce the level of reactive oxygen species (ROS), which may help to reduce the severity of diabetic cardiomyopathy. SIRT2 can affect a variety of cardiovascular diseases, energy metabolism and the ageing of cardiomyocytes, thereby affecting heart failure. SIRT2 also plays an important role in vascular disease. For endothelial cell damage used by oxidative stress, the role of SIRT2 is bidirectional, which is related to the degree of oxidative stress stimulation. When the degree of stimulation is small, SIRT2 plays a protective role, and when the degree of stimulation increases to a certain level, SIRT2 plays a negative role. In addition, SIRT2 is also involved in the remodelling of blood vessels and the repair of skin damage.

Aims Cardiac complications are common and associated with mortality in critically ill patients with COVID‐19; however, the diagnostic and prognostic implications of critical care echocardiography (CCE) have not been studied. Methods and results A cohort of 43 patients with COVID‐19 who were in the intensive care unit (ICU) underwent bedside CCE during their disease course. Demographic, clinical, and survival data were collected. The echocardiographic analyses revealed high frequencies of pericardial effusion (90.7%), increased left ventricular mass index (60.5%), elevated relative wall thickness (76.7%), and reduced left ventricular stroke volume index (LVSVi; 53.5%) and cardiac index (51.2%). Twenty‐two (51.2%) patients died in the ICU. In multivariate Cox regression, the strongest predictor of in‐ICU death was decreased cardiac index [hazard ratio (HR), 0.67, 95% confidence interval (CI), 0.45–0.98; P = 0.041], after adjusting for male sex, shock status, high‐sensitivity cardiac troponin I, and N‐terminal pro‐B‐type natriuretic peptide. Negative associations with mortality were observed for LVSVi (HR, 0.91, 95% CI 0.85–0.96; P = 0.002), tricuspid annular plane systolic excursion (HR, 0.74, 95% CI 0.64–0.84; P

A highly reusable magnetic polymer beads was employed as adsorbent to extract Ag+ and Zn2+ from aqueous solution. Because of its excellent ability to adsorb Ag+ and Zn2+, after adsorption, the residual concentration of Zn2+ or Ag+ is far lower than the wastewater discharge Standard of China. The pseudo-second-order kinetic model was suitable to describe the responding adsorption behavior. The adsorption isotherm of Ag+ fitted best with Langmuir model, suggesting a monolayer adsorption occurred between metal ions on these magnetic beads. But the adsorption isotherm of Zn2+ could be well described by Freundlich model. From the thermodynamic parameters, it indicated that this adsorption process was endothermic. Furthermore, the binding metal ions on the magnetic adsorbent could be easily recovered by eluting with acidic solution without changing the valance state of these metal ions. Moreover, the responding regeneration of these magnetic beads could be performed in alkali solution. Even after 20 runs of adsorption–desorption–regeneration, the adsorption ability of these magnetic beads changed little. These advantages, including excellent stability, favorable adsorption capacity, simple operation, and prominent recoverability, bring great potential to this technology in the removal of hazardous heavy metal ions from wastewater.

This work describes the preparation and characterization of a magnetic palladium catalyst with bulky N-heterocyclic carbene (NHC) ligands for the Suzuki–Miyaura cross-coupling reaction. After the 1-(2,6-diisopropylphenyl)-1H-imidazole (1-arylimidazole) was modified on the surface of magnetic polymer carriers, palladium diacetate was employed to synthesize the Pd-NHC complex, affording a palladium loading of 0.23 mmol g−1. This magnetic catalyst showed high catalytic activity towards the Suzuki–Miyaura reaction of phenylboronic acids with aryl bromides in the ethanol–water solution (TON > 87 000). After 21 cycling runs, its catalytic activity decreased slightly, and no leaking of palladium was found either in products or in reaction residue. When other sources of palladium (PdCl2 and 3-Cl-pyridinyl) were employed to synthesize the palladium complex, the stability of the magnetic catalyst was greatly improved to perform the catalysis of Suzuki–Miyaura reactions with aryl chlorides at 100 °C.

Hierarchical architecture is of vital importance in soft materials. Focal conic domains (FCDs) of smectic liquid crystals, characterized by an ordered lamellar structure, attract intensive attention. Simultaneously tailoring the geometry and clustering characteristics of FCDs remains a challenge. Here, the 3D smectic layer origami via a 2D preprogrammed photoalignment film is accomplished. Full control of hierarchical superstructures is demonstrated, including the domain size, shape, and orientation, and the lattice symmetry of fragmented toric FCDs. The unique symmetry breaking of resultant superstructures combined with the optical anisotropy of the liquid crystals induces an intriguing polarization-dependent diffraction. This work broadens the scientific understanding of self-assembled soft materials and may inspire new opportunities for advanced functional materials and devices.

Although polysulfone (PSU) is a potential thermoplastic engineering plastic with high heat resistance, good dimensional stability and excellent mechanical properties, its poor processability has greatly restricted its application in electrical, aerospace, and medical fields. In this work, polyamide 6 (PA6) and PSU-PA6 block copolymer (PSU-b-PA6) were used to improve the processibility and formability of PSU depending on their excellent fluidity and good compatibility between two components. Furthermore, the fluidity, thermal and mechanical properties of the blends were carefully investigated. It was found that, melt flow index of PSU could be increased above 10 times, and strength and toughness could be enhanced by 4–10% with the introduction of 10 wt % PA6 and PSU-b-PA6 without compromising the heat resistance of PSU obviously. The processing conditions of PSU could be improved while maintaining a decent comprehensive performance. Thus, the method has great potential for extending the applications of PSU. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41139.

Dialkyl-(1-benzotriazoimethyl)phosphonates are synthesized through reaction of sodium dialkyl phosphites with 1-(chloromethyl)benzotriazole in good yields.

The Horner-Wadsworth-Emmons olefination of diethyl-(1-benzotri-azolmethyl)phosphonate by means of aldehydes was found to be a convenient method for the stereoselective preparation of (E)-1-(1-Alkenyl)benzotriazoles.

The reaction of allylic thioureas with phenylselenenyl chloride affords 2‐amino dihydrothiazoles in excellent yields by selenium‐induced cyclization of allylic thioureas.

A novel synthetic method for the preparation of β-keto esters has been developed. α-Phenylseleno acetate was treated with LDA to produce a selenium-stabilised carbanion, which reacted with aldehydes, followed by selenoxide syn-elimination, to give β-keto esters.

Polystyrene-bound phenylseleninic acid was prepared conveniently and aldehydes were catalytically oxidised to carboxylic acids with hydrogen peroxide using this polymer as catalyst.