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Objective: Type 1 and type 2 diabetes are associated with gut dysbiosis. However, the relationship between the gut microbiota and latent autoimmune diabetes in adults (LADA), sharing clinical and metabolic features with classic type 1 and type 2 diabetes, remains unclear. Here, we used a multiomics approach to identify the characteristics of the gut microbiota and metabolic profiles in patients with LADA.Research Design and Methods: This age- and sex-matched case-control study included 30 patients with LADA, 31 patients with classic type 1 diabetes, 30 patients with type 2 diabetes, and 29 healthy individuals. The gut microbiota profiles were identified through the 16S rRNA gene, and fecal and serum metabolites were measured through untargeted liquid chromatography-mass spectrometry.Results: Patients with LADA had a significantly different structure and composition of the gut microbiota and their metabolites as well as a severe deficiency of short-chain fatty acid-producing bacteria. The gut microbiota structure of the patients with LADA was more similar to that of patients with type 1 diabetes who were positive for GAD antibody. We identified seven serum metabolite modules and eight fecal metabolite modules that differed between the LADA group and the other groups.Conclusions: The characteristic gut microbiota and related metabolites of patients with LADA are associated with autoantibodies, glucose metabolism, islet function, and inflammatory factors, which may contribute to the pathogenesis of LADA. Future longitudinal studies should explore whether modulating the gut microbiota and related metabolites can alter the natural course of autoimmune diabetes in the quest for new therapeutics. [ABSTRACT FROM AUTHOR]

Hydration of ions/molecules in nanometer-sized clusters or nanoscopic pores is ubiquitous and plays a key role in many chemical and physical systems. In this work, guanidine–H2O reactions with n = 1–8 water molecules were systematically studied by ab initio methods. The result suggests that the reduced availability of water molecules greatly inhibits the strong base guanidine from producing OH−. That is, guanidine exhibits the behavior of a weak bases in low-humidity nanoscale environments. Intriguingly, this effect is not limited to guanidine but could be applied to other strong bases. Furthermore, we demonstrate that the direction of guanidine–CO2 reactions can be controlled by changing the number of water molecules present, which in turn responds to the humidity change in air. These findings not only shed some light on unconventional chemical reactions of strong bases in atmospheric clusters and on solid porous surfaces, but also provide insights into the development of guanidine-based CO2 air-capture sorbents. [ABSTRACT FROM AUTHOR]

Die Dringlichkeit, den durch Treibhausgasemissionen verursachten globalen Klimawandel anzugehen, wächst von Tag zu Tag. Insbesondere der Anstieg der atmosphärischen CO2‐Werte löst Alarm aus. Technologien zum Absorbieren von CO2 aus der Umgebungsluft, oder "Direct Air Capture" (DAC), haben kürzlich gezeigt, dass sie zu "negativen Kohlenstoffemissionen" beitragen können. Die jüngsten Fortschritte in der Oberflächenchemie und der Materialsynthese haben neue Generationen von CO2‐Sorptionsmitteln ermöglicht, die möglicherweise die Zukunft von DAC und seiner großangelegten Verwendung vorantreiben können. In diesem Aufsatz werden die wichtigsten Arten von Sorptionsmitteln zur Gewinnung von CO2 aus der Umgebungsluft beschrieben und nach Sorptionsmechanismen kategorisiert: Physisorption, Chemisorption und Feuchtigkeitswechsel‐Sorption. [ABSTRACT FROM AUTHOR]

The urgency to address global climate change induced by greenhouse gas emissions is increasing. In particular, the rise in atmospheric CO2 levels is generating alarm. Technologies to remove CO2 from ambient air, or "direct air capture" (DAC), have recently demonstrated that they can contribute to "negative carbon emission." Recent advances in surface chemistry and material synthesis have resulted in new generations of CO2 sorbents, which may drive the future of DAC and its large‐scale deployment. This Review describes major types of sorbents designed to capture CO2 from ambient air and they are categorized by the sorption mechanism: physisorption, chemisorption, and moisture‐swing sorption. [ABSTRACT FROM AUTHOR]

Direct air capture (DAC) of CO2 is an emerging technology in the battle against climate change. Many sorbent materials and different technologies such as moisture swing sorption have been explored for this application. However, developing efficient scaffolds to adopt promising sorbents with fast kinetics is challenging, and very limited effort has been reported to address this critical issue. In this work, the availability and kinetic uptake of CO2 in sorbents embedded in various matrices are studied. Three scaffolds including a commercially available industrial film containing ion‐exchange resin (IER), IER particles embedded in dense electrospun fibers, and IER particles embedded in porous electrospun fibers are compared, in which a solvothermal polymer additive removal technique is used to create porosity in porous fibers. A frequency response technique is developed to measure the uptake capacity, sorbent availability, and kinetic uptake rate. The porous fiber has 90% IER availability, while the dense fibers have 50% particle accessibility. The sorption half time for both electrospun fiber samples is 10 ± 3 min. Our experimental results demonstrate that electrospinning polymer/sorbent composites is a promising technology to facilitate the handleability of sorbent particles and to improve the sorption kinetics, in which the IER embedded in porous electrospun fibers shows the highest cycle capacity with an uptake rate of 1.4 mol CO2 per gram‐hour. © 2018 American Institute of Chemical Engineers AIChE J, 65: 214–220, 2019 [ABSTRACT FROM AUTHOR]