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Additionally, chemical oxidation of the U(IV) precursor U(N3)(BCMA)3 yielded the cationic U(V) species [U(N3)(BCMA)3][OTf]. Magnetic susceptibility measurements confirmed a U(IV) oxidation state for the uranium centers in the three nitride-bridged complexes and provided a comparison of magnetic behavior in the structurally related U(III)-U(IV)-U(V) series U(BCMA)3, U(N3)(BCMA)3, and [U(N3)(BCMA)3][OTf]. At 240 K, the magnetic moments in this series decreased with increasing oxidation state, i.e., U(III) > U(IV) > U(V); this trend follows the decreasing number of 5f valence electrons along this series.Indium-gallium-zinc oxide- and zinc oxynitride-based heterojunction phototransistors were successfully demonstrated to control the persistent photoconduction (PPC) effect and be also responded sensitively at the range from visible to near-infrared. ZnON plays a key role in extending the spectral response at various frequencies of operation. The devices show significantly different photoresponse and photorecovery characteristics depending on the number of stacked layers of IGZO and ZnON. After negative bias and illumination stress was applied to the devices for 1 h, tandem-structure-based phototransistors recovered remarkably better than single-component IGZO devices. We suggest that the improvements to photoresponse and photorecovery result from the presence of potential wells between two IGZO layers and the energy band alignment of the tandem structure.Vibrio cholerae is the causative agent of cholera, a diarrheal disease that kills tens of thousands of people each year. Cholera is transmitted primarily by the ingestion of drinking water contaminated with fecal matter, and a safe water supply remains out of reach in many areas of the world. In this Review, we discuss host and environmental factors that impact the susceptibility to V. cholerae infection and the severity of disease.The structure-function relationships of plant-based proteins that give rise to desirable texture attributes in order to mimic meat products are generally unknown. In particular, it is not clear how to engineer viscoelasticity to impart cohesiveness and proper mouthfeel; however, it is known that intermolecular β-sheet structures have the potential to enhance the viscoelastic property. Here, we investigated the propensity of selected peptide segments within common corn α-zein variants to maintain stable aggregates and β-sheet structures. Simulations on dimer systems showed that stability was influenced by the initial orientation and the presence of contiguous small hydrophobic residues. Simulations using eight-peptide β-sheet oligomers revealed that peptide sequences without proline had higher levels of β-sheet structuring. Additionally, we identified that sequences with a dimer hydrogen-bonding density of >22% tended to have a larger percent β-sheet conformation. These results contribute to understanding how the viscoelasticity of zein can be increased for use in plant-based meat analogues.The spontaneous phase separation of two or more polymers is a thermodynamic process that can take place in both biological and synthetic materials and which results in the structuring of the matter from the micro- to the nanoscale. For photonic applications, it allows forming quasi-periodic or disordered assemblies of light scatterers at high throughput and low cost. The wet process methods currently used to fabricate phase-separated nanostructures (PSNs) limit the design possibilities, which in turn hinders the deployment of PSNs in commercialized products. To tackle this shortcoming, we introduce a versatile and industrially scalable deposition method based on the inkjet printing of a polymer blend, leading to PSNs with a feature size that is tuned from a few micrometers down to sub-100 nm. Consequently, PSNs can be rapidly processed into the desired macroscopic design. We demonstrate that these printed PSNs can improve light management in manifold photonic applications, exemplified here by exploiting them as a light extraction layer and a metasurface for light-emitting devices and point-of-care biosensors, respectively.A strategy to match any retention shifts due to increased or decreased pressure drop during supercritical fluid chromatography (SFC) method transfer is presented. The strategy relies on adjusting the co-solvent molarity without the need to adjust the back-pressure regulator. Exact matching can be obtained with minimal changes in separation selectivity. To accomplish this, we introduce the isomolar plot approach, which shows the variation in molar co-solvent concentration depending on the mass fraction of co-solvent, pressure, and temperature, here exemplified by CO2-methanol. This plot allowed us to unify the effects of the co-solvent mass fraction and density on retention in SFC. The approach, which was verified on 12 known empirical retention models for each enantiomer of six basic pharmaceuticals, allowed us to numerically calculate the apparent retention factor for any column pressure drop. The strategy can be implemented either using a mechanistic approach if retention models are known or empirically by iteratively adjusting the co-solvent mass fraction. As a rule of thumb for the empirical approach, we found that the relative mass fraction adjustment needed is proportional to the relative change in the retention factor caused by a change in the pressure drop. Different proportionality constants were required to match retention in the case of increasing or decreasing pressure drops.Field asymmetric ion mobility spectrometry (FAIMS), when used in proteomics studies, provides superior selectivity and enables more proteins to be identified by providing additional gas-phase separation. Here, we tested the performance of cylindrical FAIMS for the identification and characterization of proteoforms by top-down mass spectrometry of heterogeneous protein mixtures. Combining FAIMS with chromatographic separation resulted in a 62% increase in protein identifications, an 8% increase in proteoform identifications, and an improvement in proteoform identification compared to samples analyzed without FAIMS. In addition, utilization of FAIMS resulted in the identification of proteins encoded by lower-abundance mRNA transcripts. These improvements were attributable, in part, to improved signal-to-noise for proteoforms with similar retention times. Additionally, our results show that the optimal compensation voltage of any given proteoform was correlated with the molecular weight of the analyte. Collectively these results suggest that the addition of FAIMS can enhance top-down proteomics in both discovery and targeted applications.Salinity gradient power (SGP) has been identified as a promising renewable energy source. Reverse electrodialysis (RED) and pressure retarded osmosis (PRO) are two membrane-based technologies for SGP harvesting. Developing nanopores and nanofluidic membranes with excellent water and/or ion transport properties for applications in those two membrane-based technologies is considered viable for improving power generation performance. Despite recent efforts to advance power generation by designing a variety of nanopores and nanofluidic membranes to enhance power density, the valid pathways toward large-scale power generation remain uncertain. In this review, we introduce the features of ion and water transport in nanofluidics that are potentially beneficial to power generation. Subsequently, we survey previous efforts on nanofluidic membrane synthesis to obtain high power density. We also discuss how the various membrane properties influence the power density in RED and PRO before moving on to other important aspects of the technologies, i.e., system energy efficiency and membrane fouling. We analyze the importance of system energy efficiency and illustrate how the delicately designed nanofluidic membranes can potentially enhance energy efficiency. Previous studies are reviewed on fabricating antifouling and antimicrobial membrane for power generation, and opportunities are presented that can lead to the design of nanofluidic membranes with superior antifouling properties using various materials. Finally, future research directions are presented on advancing membrane performance and scaling-up the system. We conclude this review by emphasizing the fact that SGP has the potential to become an important renewable energy source and that high-performance nanofluidic membranes can transform SGP harvesting from conceptual to large-scale applications.The KCNN4 gene encoding a potassium channel protein whose expression has been correlated with tumor progression was found to comprise a guanine-rich minisatellite region with the ability to form a putative G-quadruplex (G4). Given the suggested regulatory role of G4s in gene expression, G-quadruplex formation for the polymorphic first repeat of the minisatellite was studied by nuclear magnetic resonance spectroscopy. A stable G-quadruplex of a truncated mutant sequence was shown to represent one of several coexisting species of the wild-type sequence. The high-resolution structure features a noncanonical G4 with a broken G-column and a V-shaped loop. The presence of a 3'-flanking thymidine interacting with the lateral loop preceding the V loop seems to be critical for the formation of this G4 topology. On the contrary, an additional 5'-flanking residue disfavored but still allowed folding into the V-loop structure. The latter may therefore serve as a putative therapeutic target in strategies for G4-based modulation of KCNN4 expression.Fabrication of metal nanoparticle (NP)-based strain sensors with both a broad working range and linearity range is still a significant challenge. Typically, homogeneous conductive percolation networks are indispensable for linear sensing performance, whereas inhomogeneous microstructures may inevitably arise under large strain due to the formation of defects in rigid NPs. In this study, a sandwich-structured strain sensor with an extraordinarily large stretchability (800%) yet self-healing property is fabricated by three-dimensional printing using a liquid metal-like Ag NP ink. The strain sensor shows an initial conductivity of 248 S cm-1, a good linearity in two strain ranges, and a long-term stability after undergoing 5000 cycles under a strain level of 100%. Such highly comprehensive sensing performance is attributed to the unique structure of the Ag NP ink, in which Ag NPs coalesce together after room-temperature sintering triggered by chlorides, and then, the sintered Ag aggregates tend to form continuous conductive networks through hydrogen bonds between polyacrylic acid and carboxymethylcellulose. Further, the free flow of Ag aggregates is the root cause that leads to the change of relative resistance as demonstrated by finite element simulation. This Ag NP-based strain sensor shows high potential for application in monitoring human knuckle motion.Molecular oxygen (O2) is a highly reactive oxidizing agent and is harmful to many biological and industrial systems. https://www.selleckchem.com/products/Estradiol.html Although O2 often interacts via metals or reducing agents, a binding mechanism involving an organic supramolecular structure has not been described to date. In this work, the prominent dipeptide hydrogelator fluorenylmethyloxycarbonyl-diphenylalanine is shown to encage O2 and significantly limit its diffusion and penetration through the hydrogel. Molecular dynamics simulations suggested that the O2 binding mechanism is governed by pockets formed between the aromatic rings in the supramolecular structure of the gel, which bind O2 through hydrophobic interactions. This phenomenon is harnessed to maintain the activity of the O2-hypersensitive enzyme [FeFe]-hydrogenase, which holds promising potential for utilizing hydrogen gas for sustainable energy applications. Hydrogenase encapsulation within the gel allows hydrogen production following exposure to ambient O2. This phenomenon may lead to utilization of this low molecular weight gelator in a wide range of O2-sensitive applications.