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Nature performs critical physiological functions using a series of structurally and functionally diverse membrane proteins embedded in cell membranes, in which native ion protein channels modify the electrical potential inside and outside the cell membrane through charged ion movements. Consequently, the cell responds to external stimuli, playing an essential role in various life activities, such as nerve excitation conduction, neurotransmitter release, muscle movement, and control of cell differentiation. Supramolecular artificial channels, which mimic native protein channels in structure and function, adopt unimolecular or self‐assembled structures, such as crown ethers, cyclodextrins, cucurbiturils, column arenes, cyclic peptide nanotubes, and metal‐organic artificial channels, in channel construction strategies. Owing to the various driving forces involved, artificial synthetic ion channels can be divided into artificial cation and anion channels in terms of ion selectivity. Cation selectivity usually originates from ion coordination, whereas anion selectivity is related to hydrogen bonding, ion pairing, and anion‐dipole interactions. Several studies have been conducted on artificial cation channels, and several reviews have summarized them in detail; however, the research on anions is still in the initial stages, and related reviews have rarely been reported. Hence, this article primarily focuses on the recent research on anion channels. [ABSTRACT FROM AUTHOR]

Metalenses have provided a good solution to the bulkiness of conventional refractive lenses. Due to the subwavelength feature sizes of the metalens structure, the increasing fabrication difficulties at high frequencies limit its application in the terahertz and optical regime. Moreover, the deeply subwavelength features of the metasurface unit cells usually make the cells strongly resonant, which limits the bandwidth of the metalens. In this paper the usage of aggressive discretization in a metalens design is investigated, and it is found that aggressive discretization can lead to the usage of weakly resonant and relatively large unit cells, which leads to excellent broadband performance and dramatically relaxes the feature size tolerance of the metalens. For examples, two terahertz focusing metalenses are designed which feature large numerical apertures (NA = 0.86), diffraction‐limited focusing over a broad bandwidth (240–400 GHz, or 50% bandwidth), and minimum feature sizes of 0.1 mm. These tolerance‐relaxed terahertz metalenses are successfully constructed using conventional printed‐circuit‐board fabrication technology. The experimental measurements validate the simulated performances. Compared to existing terahertz meta‐devices based on micro‐fabrication or nano‐fabrication technologies, this paper opens door to a kind of high‐quality terahertz metasurfaces featuring low‐cost, rapid, and established fabrication. [ABSTRACT FROM AUTHOR]

gem‐Dibromoalkanes are important synthetic building block in organic chemistry, but their preparation is still troublesome. Herein, we have developed a simple and practical protocol for the synthesis of gem‐dibromoalkanes from aldehydes using tetrabutylammonium tribromide and triphenyl phosphite. A variety of alkyl and aromatic aldehydes can be transformed into the corresponding products within 10 minutes. This protocol is also applicable to alcohols, and the configuration of chiral alcohol is inverted during the process with excellent enantiopurity. [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the biomechanics of a novel fusion strategy (hybrid internal fixation+horizontal cage position) in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Methods. MIS-TLIF finite element models for three fusion strategies were created based on computed tomography images, namely, Model-A, hybrid internal fixation (ipsilateral pedicle screw and contralateral translaminar facet screw fixation)+horizontal cage position; Model-B, bilateral pedicle screw (BPS) fixation+horizontal cage position; and Model-C, BPS fixation+oblique 45° cage position. A preload of 500 N and a moment of 10 Nm were applied to the models to simulate lumbar motion, and the models' range of motion (ROM), peak stress of the internal fixation system, and cage were assessed. Results. The ROM for Models A, B, and C were not different (P > 0.05) but were significantly lower than the ROM of Model-INT (P < 0.0001). Although there were subtle differences in the ROM ratio for Models A, B, and C, the trend was similar. The peak stress of the internal fixation system was significantly higher in Model-A than that of Models B and C, but only the difference between Models A and B was significant (P < 0.05). The peak stress of the cage in Model-A was significantly lower than that of Models B and C (P < 0.01). Conclusion. Hybrid internal fixation with horizontal single cage implantation can provide the same biomechanical stability as traditional fixation while reducing peak stress on the cage and vertebral endplate. [ABSTRACT FROM AUTHOR]

The reactivity of N‐tosyl vinylaziridines toward arynes has been demonstrated under mild and transition‐metal‐free conditions to yield 2‐(phenanthren‐9‐yl)ethan‐1‐sulfamides in moderate to good yields. The selective synthesis of N‐H and N‐aryl products was accomplished using CsF in MeCN and KF/18‐C‐6 in 1,4‐dioxane, respectively. This cascade process involves a sequential Diels‐Alder reaction, ring‐opening aromatization, ene‐reaction, and selective N‐arylation reaction. [ABSTRACT FROM AUTHOR]

Developing non‐precious bifunctional electrocatalysts to drive the over water splitting that can operate well at high current densities (1,000 mA/cm2) is an urgent requirement for viable electrolysis of water. Transition metal oxides (TMO) have been intensely investigated as one of the most efficient oxygen evolution reaction (OER) catalysts. Unfortunately, their sluggish reaction kinetics towards hydrogen evolution reaction (HER) bring about poor overall performance. In this study, we perform a simple method to obtain the bifunctional TMO‐based electrocatalyst by in‐situ tailoring the components of cobalt nickel molybdenum oxide on nickel foam. By optimizing the annealing temperature and reaction atmosphere, we integrate HER‐active (CoMoNi) and OER‐active (CoMoOx) components together as bifunctional electrocatalysts for overall water splitting. Impressively, the as‐synthesized electrocatalyst shows the high electrocatalytic activity for both OER and HER, and exhibit a low cell voltage of 1.59 V at 10 mA cm−2 when applied as both the cathode and anode in alkaline solutions. Impressively, the bifunctional electrocatalysts work well at large current densities, even in the order of 1,000 mA cm−2 (only need the cell voltage of ∼2.03 V), and remain its activity more than 20 h. Such an outstanding performance should be mainly attributed to integrated high electronic conductivity, 3D self‐supported structure, and good compatibility between HER‐active and OER‐active components. This study shows a positive model for the design of more promising and practical catalysts for full water splitting. On the fly: in‐situ formed hydrogen evolution reaction‐active (CoMoNi) and oxygen evolution reaction‐active (CoMoOx) components are integrated on nickel foam as bifunctional electrocatalyst for overall water splitting. It requires a low cell voltage of ∼2.03 V to reach a current density of 1,000 mA cm−2, and remains activity for more than 20 h. [ABSTRACT FROM AUTHOR]

Shape memory cryogels hold immense promise for non‐compressible hemostasis due to their shape recovery after contacting with blood. However, there is still a lack of an easy way to accelerate the shape‐recovery speed which is highly associated with its performance. Meanwhile, the incorporation of extra pro‐coagulation mechanisms will further improve the hemostatic efficacy. Herein, surfactant‐stabilized bubbles are used to improve the shape‐recovery speed of cryogels (GHP) through the modulation of porosity and pore size based on the capillary action. Additionally, 2D nanosheet vermiculite (VMT) is fabricated and incorporated into the system to get VMT@GHP cryogels. Remarkably, VMT@GHP exhibits a fast shape recovery speed (1.3 ± 0.3 s in the blood) among reported hemostats and the ability to promote blood coagulation. Animal studies show that VMT@GHP significantly accelerates the hemostasis in both rat and pig models, even in heparinized situations. In summary, VMT@GHP represents a highly effective solution for non‐compressible hemorrhage control, with promising prospects for clinical translation. [ABSTRACT FROM AUTHOR]

Issue Addressed Methods Results Conclusions So What? Food environments surrounding schools have a strong influence on the adolescent's food choices. Moreover, the prevalence of diet‐related chronic diseases is higher in regional than metropolitan areas in Australia. Understanding school food environments in these different settings is crucial for informing future strategies to improve adolescent health.Google Street View was used to identify food outlets within 1.6 km around all secondary schools in Wagga Wagga and Blacktown in New South Wales which were selected as regional and metropolitan case study areas. Based on food outlet type, healthfulness categories were assigned, and Chi‐squared tests were performed. The Health Advisory Panel for Youth at the University of Sydney (HAPYUS) were engaged to obtain their perspectives on findings.Unhealthful food outlets were consistently most prevalent around schools in Wagga Wagga and Blacktown over 17 years. In 2023, these were predominantly restaurants (19.4% vs. 21.1%), cafés (16.8% vs. 11.1%), fast‐food franchise outlets (15.1% vs. 17.4%) and independent takeaway stores (14.1% vs. 9.6%). No significant difference in healthfulness between regional and metropolitan areas was found. Youth advisors recognised price and social reasons as major contributors to food choices.Google Street View was used as a novel resource to examine school food environments in regional and metropolitan areas which have remained consistently unhealthful for nearly two decades.Unhealthful school food environments may encourage poor diets and exacerbate rates of adolescent overweight and obesity. Critical government action is needed to improve school food environments. [ABSTRACT FROM AUTHOR]