Rutledgehawley8174

Proteins are ubiquitous and play a critical role in many areas from living organisms to protein microchips. In humans, serum albumin has a prominent role in the foreign body response since it is the first protein which will interact with, e.g., an implant or stent. In this study, we focused on the influence of salts (i.e., different cations (Y3+, La3+) and anions (Cl-, I-) on bovine serum albumin (BSA) in terms of its bulk behavior as well as the role of charges for protein adsorption at the solid-liquid interface in order to understand and control the underlying molecular mechanisms and interactions. This is part of our group's effort to gain a deeper understanding of protein-protein and protein-surface interactions in the presence of multivalent ions. In the bulk, we established two new phase diagrams and found not only multivalent cation-triggered phase transitions, but also a dependence of the protein behavior on the type of anion. The attractive interactions between proteins were observed to increase frohe way for specific/triggered protein-protein, protein-salt, and protein-surface interactions.The rapid development of quantum information processors has accelerated the demand for technologies that enable quantum networking. One promising approach uses mechanical resonators as an intermediary between microwave and optical fields. Signals from a superconducting, topological, or spin qubit processor can then be converted coherently to optical states at telecom wavelengths. However, current devices built from homogeneous structures suffer from added noise and a small conversion efficiency. Combining advantageous properties of different materials into a heterogeneous design should allow for superior quantum transduction devices-so far these hybrid approaches have however been hampered by complex fabrication procedures. check details Here we present a novel integration method, based on previous pick-and-place ideas, that can combine independently fabricated device components of different materials into a single device. The method allows for a precision alignment by continuous optical monitoring during the process. Using our method, we assemble a hybrid silicon-lithium niobate device with state-of-the-art wavelength conversion characteristics.Bicyclic compounds bearing a quaternary stereogenic center have been obtained using asymmetric intramolecular Buchner reaction with excellent yields and level of enantioselectivity. X-ray crystallography determination of the absolute configuration of one product has led to the serendipitous observation of an unusual behavior within the crystal structure, with equilibrating norcaradiene and cycloheptatriene valence isomers at the solid state, as well as an even more unexpected intermediate form. DFT calculations were performed to support these observations.Droplet manipulations are critical for applications ranging from biochemical analysis, medical diagnosis to environmental controls. Even though magnetic actuation has exhibited great potential, the capability of high-speed, precise manipulation, and mixing improvement covering a broad droplet volume has not yet been realized. Herein, we demonstrated that the magnetic actuation could be conveniently achieved via decorating the magnetically responsive film with microcilia. Under magnetic field, the film can quickly response with localized deformation, along with the microcilia to realize the surface superhydrophobicity for droplet manipulation with velocity up to ∼173 mm/s covering a broad volume of 2-100 μL. The robust system further allows us to realize rapid and complete droplet mixing within ∼1.6 s. In addition, the microcilia decorated surface can preserve the robust superhydrophobicity after various stability tests, for example, normal pressing, chemical corrosion, and mechanical abrasion, exhibiting the possibility toward the long-term and real applications. With the multifunctional demonstrations such as obvious mixing improvement, parallel manipulation, and serial dilution, we believe that the methodology can open up a magnetic field-based avenue for future applications in digital microfluidics, and biochemical assays, etc.Chitooligosaccharides (COS) generated from either chitin (chitin oligosaccharides) or chitosan (chitosan oligosaccharides) have a wide range of applications in agriculture, medicine, and other fields. Here, we report the characterization of a chitosanase from Bacillus amyloliquefaciens (BamCsn) and the importance of a tryptophan (Trp), W204, for BamCsn activity. BamCsn hydrolyzed the chitosan polymer by an endo mode. It also hydrolyzed chitin oligosaccharides and interestingly exhibited transglycosylation activity on chitotetraose and chitopentaose. Mutation of W204, a nonconserved amino acid in chitosanases, to W204A abolished the hydrolytic activity of BamCsn, with a change in the structure that resulted in a decreased affinity for the substrate and impaired the catalytic ability. link2 Phylogenetic analysis revealed that BamCsn could belong to a new class of chitosanases that showed unique properties like transglycosylation, cleavage of chitin oligosaccharides, and the presence of W204 residues, which is important for activity. Chitosanases belonging to the BamCsn class showed a high potential to generate COS from chitinous substrates.A class of amino acid-based low-molecular-weight gelators (LMWGs) was used for single and multicomponent gel studies to investigate their tunable optical properties and their self-assembly process. The optical properties of multicomponent gels were found to be easily tuned by changing the proportion of the components, varying from opaque to highly transparent gels as analyzed using ultraviolet-visible spectroscopy. This phenomenon allows tunability without introducing another variable into the system. Scanning electron microscopy, differential scanning calorimetry, and small-angle X-ray scattering (SAXS) were used to investigate the structures of the gels. It was found that because of the structural similarities of the molecules, the gelators favor coassembly packing over self-sorting. The emergence of transparency was ascribed to changes in the fiber diameters. Moreover, analysis of the SAXS data allowed us to compare the molecular order present in the gel phase with single-crystal X-ray diffraction (SCXRD) data. Our analysis suggests that the packing of molecules seen in the crystalline phase is translated into the gel network. This reveals that the structure of the crystalline phase seen through SCXRD is a useful tool to aid in understanding the molecular packing in the gel phase.Liquids confined to sub-millimeter scales have remained poorly understood. One of the most striking effects is the large elasticity revealed using good wetting conditions, which grows upon further decreasing the confinement length, L. These systems display a low-frequency shear modulus in the order of 1-103 Pa, contrary to our everyday experience of liquids as bodies with a zero low-frequency shear modulus. While early experimental evidence of this effect was met with skepticism and abandoned, further experimental results and, most recently, a new atomistic theoretical framework have confirmed that liquids indeed possess a finite low-frequency shear modulus G', which scales with the inverse cubic power of confinement length L. We show that this law is universal and valid for a wide range of materials (liquid water, glycerol, ionic liquids, non-entangled polymer liquids, isotropic liquids crystals). Open questions and potential applications in microfluidics mechanochemistry, energy, and other fields are highlighted.We present a basis-set-free approach to the variational quantum eigensolver using an adaptive representation of the spatial part of molecular wave functions. Our approach directly determines system-specific representations of qubit Hamiltonians while fully omitting globally defined basis sets. In this work, we use directly determined pair-natural orbitals on the level of second-order perturbation theory. This results in compact qubit Hamiltonians with high numerical accuracy. We demonstrate initial applications with compact Hamiltonians on up to 22 qubits where conventional representation would for the same systems require 40-100 or more qubits. We further demonstrate reductions in the quantum circuits through the structure of the pair-natural orbitals.In charge-transfer complexes, transition from the donor highest occupied molecular orbital (HOMO) to the acceptor lowest unoccupied molecular orbital (LUMO) gives the charge-transfer absorption. However, in tetracyanoquinodimethane (TCNQ) complexes of thienoacenes, comparison of the observed and calculated charge-transfer absorption demonstrates that the HOMO/LUMO transition is absent in the solid state owing to the orbital symmetry, and the first near-infrared band comes from the transition from the donor next HOMO to the TCNQ LUMO. Maps of the oscillator strength in rotated and translated molecular geometries are calculated on the basis of the time-dependent density functional theory, in which the absence of the HOMO/LUMO transition is approximately maintained even in the general molecular geometry.[(Pentamethylcyclopentadienyl)Rh(III)(bipyridine)(chloride)]+ (Cp*Rh-Cl) undergoes sequential deuteriation of its 15 Cp* CH groups in polar deuterated solvents. Vibrational spectra of H 14 -Cp*Rh-Cl and D 14 -Cp*Rh-Cl were captured via inelastic neutron spectroscopy (INS) and assigned using density functional theory (DFT) phonon calculations. These calculations were precisely weighted to the spectrometer's neutronic response. The Cp* ring behaves as a moving carousel, bringing each CH3 close to the Rh-OH/D center where proton abstraction occurs. Vibrations relevant for carousel movement and proximal positioning for H transfer were identified. DFT modeling uncovered changes in vibrations along the reaction path, involving a Rh(I)-fulvene intermediate. Vibronic energy contributions are large across the entire transition. Remarkably, they amount to over a 400-fold increase in the proton transfer rate. The inclusion of vibrational degrees of freedom could be applied more widely to catalysts and molecular machines to harness the energetics of these vibrations and increase their effective rates of operation.Additive-free copper(I)-bromide-mediated radical cyclization reactions of α,α-dibromo β-iminoesters were investigated, enabling the synthesis of a series of 5- or 6-brominated 2-aryl-1H-indole-3-carboxylates in moderate to good yields. link3 The mechanistic study showed that (i) the bromine atom originated from the substrates and (ii) the bromination might be related to a 3-bromo-3H indole intermediate via an electrophilic bromine atom transfer. Furthermore, the practicality of this method was demonstrated by gram-scale synthesis and the potential for product derivatization toward other valuable multisubstituted indoles.A series of novel bismuth-bridged viologen analogues, bismoviologens (BiV2+), synthesized through a combination of a bismuth atom and viologen skeleton is reported. Their optical and electrochemical properties were fine-tuned through the N-arylation or N-alkylation reactions. Bismolviologens not only showed good redox properties but also exhibited phosphorescence under ambient conditions (in air at room temperature). This phenomenon makes BiV2+ the first examples of phosphorescent viologen analogues reported to date. On the basis of the excellent and unique redox and optical properties of BiV2+, their electrophosphorochromic devices were fabricated. Furthermore, BiV2+ was used for the first time as both a photocatalyst and electron mediator in visible light-induced cross-dehydrogenative coupling reactions.