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The complex distribution of functional groups in carbohydrates, coupled with their strong solvation in water, makes them challenging targets for synthetic receptors. Despite extensive research into various molecular frameworks, most synthetic carbohydrate receptors have exhibited low affinities, and their interactions with sugars in aqueous environments remain poorly understood. In this work, we present a simple pyridinium-based hydrogen-bonding receptor derived from a subtle structural modification of a well-known tetralactam macrocycle. This small structural change resulted in a dramatic enhancement of glucose binding affinity, increasing from 56 M−1 to 3001 M−1. Remarkably, the performance of our synthetic lectin surpasses that of the natural lectin, concanavalin A, by over fivefold. X-ray crystallography of the macrocycle–glucose complex reveals a distinctive hydrogen bonding pattern, which allows for a larger surface overlap between the receptor and glucose, contributing to the enhanced affinity. Furthermore, this receptor possesses allosteric binding sites, which involve chloride binding and trigger receptor aggregation. This unique allosteric process reveals the critical role of structural flexibility in this hydrogen-bonding receptor for the effective recognition of sugars. We also demonstrate the potential of this synthetic lectin as a highly sensitive glucose sensor in aqueous solutions. 

In the past three years, the COVID-19 pandemic has caused serious health, environmental, societal, and economic challenges globally. Sterilization is one of the most efficient methods to mitigate the spread of infectious viruses like SARS-CoV-2. However, extreme sterilization practices can cause serious health and environmental problems worldwide. Heat, ultraviolet C (UVC), and chemical disinfectants require high energy consumption and can cause health concerns, environmental pollution, and chemical overuse. In this paper, we evaluated the efficiency of corona discharge (CD) as an environmentally and energy-friendly sterilization method on different surfaces for sterilization. It was confirmed that CD is an efficient sterilization process for most surfaces and personal protective equipment (PPE). CD allows for a reduction in disinfectant use, addresses the PPE shortage problem, and reduces plastic pollution and biowaste. The air sterilization effect of CD creates a promising option to reduce airborne pathogens. To address the safety concerns of CD, the heat, UVC, and ozone emissions of CD were confirmed to be within a safe range. A wireless, affordable CD robot was developed with the capability to scan along pre-designed paths while having the capability to avoid static and moving obstacles. Automated CD devices and robots can be favorable sterilization solutions for the future as a contactless, more environmentally friendly, efficient, affordable, and portable solution. 

Glycine, the simplest amino acid, is considered a promising functional biomaterial owing to its excellent biocompatibility and strong out-of-plane piezoelectricity. Practical applications require glycine films to be manufactured with their strong piezoelectric polar 〈001〉 direction aligned with the film thickness. Based on the recently-developed solidification approach of a polyvinyl alcohol (PVA) and glycine aqueous solution, in this work, we demonstrate that the crystal orientation of the as-synthesized film is determined by the orientation of glycine crystal nuclei. By controlling the local nucleation kinetics via surface curvature tuning, we shifted the nucleation site from the edge to the middle of the liquid film, and thereby aligned the 〈001〉 direction vertically. As a result, the PVA–glycine–PVA sandwich film exhibits the highest aver-age piezoelectric coefficient d 33 of 6.13 ± 1.13 pC N −1 . This work demonstrates a promising kinetic approach to achieve crystallization and property control in a scalable biocrystal manufacturing process. 

Abstract The summer intraseasonal oscillation (ISO) is characterized by a northward-moving rainband in the Indo–western Pacific warm pool region. The physical origin of the ISO is not fully understood, as it is masked by strong interaction of convection and circulation. This study examines intraseasonal to interannual variability during June–August over the Indo–western Pacific warm pool region. The results show that the tropical northwest Pacific anomalous anticyclone (NWP-AAC) is a fundamental mode on both intraseasonal and interannual time scales, destabilized by the monsoon mean state, specifically through barotropic energy conversion and convective feedback in the low-level confluence between the monsoon westerlies and easterly trade winds. On the interannual time scale, the NWP-AAC shows a biennial tendency, reversing phase from the summer of El Niño to the summer that follows; the AAC in post–El Niño summer is excited indirectly through sea surface temperature anomalies in the Indo–NWP. On the intraseasonal time scale, the column-integrated moisture advection causes the NWP-AAC-related convection to propagate northward. Our results provide a unifying view of multiscale Asian summer monsoon variability, with important implications for subseasonal to seasonal prediction.