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A molecularly imprinted electrochemiluminescence sensor was prepared for sensitive and selective determination of aminotriazole via a novel strategy of multiple Ru(bpy)3Cl2 probes released from liposomes immobilized by a light-triggered click reaction. This sensing strategy provides a platform for trace detection of amino-containing pesticides. The target on the molecularly imprinted membrane connected to the Ru(bpy)3Cl2-encapsulated liposomes via the click reaction. After the destabilizing agent Triton X-100 was added, numerous Ru(bpy)3Cl2 molecules were released by liposomes on the molecularly imprinted polymer electrode. The ECL response of the sensor was linearly proportional to the logarithm of the aminotriazole concentration ranging from 5.00 × 10-18 to 1.00 × 10-12 mol/L, and the detection limit was 1.15 × 10-18 mol/L. The sensitivity of the detection was significantly improved, and the analysis process was simplified.To design novel antimicrobial peptides by utilizing the sequence of the human host defense protein, chemerin, a seven-residue amphipathic stretch located in the amino acid region, 109-115, was identified, which possesses the highest density of hydrophobic and positively charged residues. Although this 7-mer peptide was inactive toward microorganisms, its 14-mer tandem repeat (Chem-KVL) was highly active against different bacteria including methicillin-resistant Staphylococcus aureus, a multidrug-resistant Staphylococcus aureus strain, and slow- and fast-growing mycobacterial species. The selective enantiomeric substitutions of its two l-lysine residues were attempted to confer cell selectivity and proteolytic stability to Chem-KVL. Chem-8dK with a d-lysine replacement in its middle (eighth position) showed the lowest hemolytic activity against human red blood cells among Chem-KVL analogues and maintained high antimicrobial properties. Chem-8dK showed in vivo efficacy against Pseudomonas aeruginosa infection in BALB/c mice and inhibited the development of resistance in this microorganism up to 30 serial passages and growth of intracellular mycobacteria in THP-1 cells.Native mass spectrometry (MS) is used to elucidate the stoichiometry of protein complexes and quantify binding interactions by maintaining native-like, noncovalent interactions in the gas phase. However, ionization forces proteins into specific conformations, losing the solution-phase dynamics associated with solvated protein structures. Comparison of gas-phase structures to those in solution, or to other gas-phase ion populations, has many biological implications. For one, analyzing the variety of conformations that are maintained in the gas-phase can provide insight into a protein's solution-phase energy landscape. The gas-phase conformations of proteins and complexes can be investigated using ion mobility (IM) spectrometry. Specifically, drift tube (DT)-IM utilizes uniform electric fields to propel a population of gas-phase ions through a region containing a neutral gas. By measuring the mobility (K) of gas-phase ions, users are able to calculate an average momentum transfer cross section (DTCCS), which pructures sampled by native IM-MS to be compared against other reported structures, both experimental and computational.Atom-efficient syntheses of the tetraethylammonium Roussin black sulfur and selenium salts ((Et4N)[Fe4E3(NO)7], E = S, Se) as well as their 15N-labeled counterparts are described herein. Broken-symmetry DFT calculations were conducted on both complexes to model an antiferromagnetic interaction between the apical FeNO7 unit, Sap = 3/2, and the three basal Fe(NO)29 units, Sbas = 1/2. The calculated J values are -1813 and -1467 cm-1 for the sulfur and selenium compounds, respectively. The mechanism for antiferromagnetic exchange in both compounds was deduced to be direct exchange on the basis of the partially overlapping magnetic orbitals with orbital density only residing on the Fe-centers. The obtained Mössbauer parameters are most consistent with the calculated MS = 0 broken-symmetry state for both complexes. The values for J have been determined with variable-temperature 15N NMR experiments. Values of -1660 and -1430 cm-1 for the sulfur and selenium compounds, respectively, were obtained by fits to the variable-temperature NMR data, further validating the broken-symmetry MS = 0 model of the electronic structure.Substantial efforts have been made in incorporating tannin-rich forages into grassland-based livestock production systems. However, the structural and functional diversity of tannins in different species limits their potential use at the field scale. We conducted a greenhouse experiment with 17 cultivars from 8 forage species and their cultivars. Ultraperformance liquid chromatography tandem mass spectrometry was used to analyze their polyphenolic profile and proanthocyanidin (PA) structural features in leaves. Our results highlight large inter- and intraspecies variability of plants in terms of polyphenol and tannin concentrations in the leaves. A concomitant and significant variation was also registered in the structural features of PA-rich forages such as the mean degree of polymerization and prodelphinidin percentage. The concentration of PA also varied within plant organs; the highest concentration was in flowers, but leaves had the highest contribution to harvestable PA biomass. Our research highlights that identifying these variations helps in identifying the representativeness of bioactivity and provides the basis for targeted breeding programs.A fiber-based triboelectric nanogenerator (F-TENG) is an important technology for smart wearables, where conductive materials and triboelectric materials are two essential components for the F-TENG. However, the different physicochemical properties between conductive metal materials and organic triboelectric materials often lead to interfacial failure problems, which is a great challenge for fabricating high-performance and stable F-TENGs. Herein, we designed a new conductive composite fiber (CCF) with customizable functionalities based on a core-spun yarn coating approach, which was applicable for a fiber-based TENG (CCF-TENG). By combing a core-spun method and a coating approach, triboelectric materials could be better incorporated on the surface of conductive fibers with the staple fibers to form a new composite structure with enhanced interfacial properties. The applicability of the method has been studied using different conductive and staple fibers and coating materials as well as different CCF diameters. As a demonstration, the open-circuit voltage and power density of the CCF-TENG reached 117 V and 213 mW/m2, respectively. Moreover, a 2D fabric TENG was woven and used as a wearable sensor for motion detection. This work provided a new method for 1D composite fibers with customizable functionalities for the applications in smart wearables.In the field of polymer informatics, utilizing machine learning (ML) techniques to evaluate the glass transition temperature Tg and other properties of polymers has attracted extensive attention. This data-centric approach is much more efficient and practical than the laborious experimental measurements when encountered a daunting number of polymer structures. Various ML models are demonstrated to perform well for Tg prediction. Nevertheless, they are trained on different data sets, using different structure representations, and based on different feature engineering methods. Thus, the critical question arises on selecting a proper ML model to better handle the Tg prediction with generalization ability. To provide a fair comparison of different ML techniques and examine the key factors that affect the model performance, we carry out a systematic benchmark study by compiling 79 different ML models and training them on a large and diverse data set. The three major components in setting up an ML model are struct the Tg prediction task but also a useful reference for other polymer informatics tasks.Transcriptional downregulation is widely used for metabolic flux control. Here, marO, a cis-element of Escherichia coli mar operator, was explored to engineer promoters of Saccharomyces cerevisiae for downregulation. First, the ADH1 promoter (PADH1) and its enhanced variant PUADH1 were engineered by insertion of marO into different sites, which resulted in decrease in both gfp5 transcription and GFP fluorescence intensity to various degrees. Then, marO was applied to engineer the native ERG1 and ERG11 promoters due to their importance for accumulation of value-added intermediates squalene and lanosterol. Elevated squalene content (4.9-fold) or lanosterol content (4.8-fold) and 91 or 28% decrease in ergosterol content resulted from the marO-engineered promoter PERG1(M5) or PERG11(M3), respectively, indicating the validity of the marO-engineered promoters in metabolic flux control. Furthermore, squalene production of 3.53 g/L from cane molasses, a cheap and bulk substrate, suggested the cost-effective and promising potential for squalene production.In this work, we fabricate multidimensional silicon-graphene hybrid nanostructures composed of three-dimensional (3D) out-of-plane graphene flakes on a silicon nanowire core. By changing the synthesis temperature (700 and 1100 °C) and time (5, 10, and 20 min), we obtain two different types of 3D graphene flakes with tunable dimensions and structure parameters. We characterize the thermal transport behavior of this hybrid multidimensional material in a broad temperature range of 20-460 K. With different morphologies and structures, the effective thermal conductivity of the silicon-graphene hybrid nanostructures varies from 1 to 7 W/(m·K) at room temperature. We also apply molecular dynamics simulation and density functional theory to elucidate the thermal transport mechanisms in the silicon-graphene hybrid nanostructures.Reversible addition-fragmentation chain transfer (RAFT) polymerization is one of the most powerful reversible deactivation radical polymerization (RDRP) processes. Rate retardation is prevalent in RAFT and occurs when polymerization rates deviate from ideal conventional radical polymerization kinetics. Herein, we explore beyond what was initially thought to be the culprit of rate retardation dithiobenzoate chain transfer agents (CTA) with more active monomers (MAMs). Remarkably, polymerizations showed that rate retardation occurs in systems encompassing the use of trithiocarbonates and xanthates CTAs with varying monomeric activities. Both the simple slow fragmentation and intermediate radical termination models show that retardation of all these systems can be described by using a single relationship for a variety of monomer reactivity and CTAs, suggesting rate retardation is a universal phenomenon of varying severity, independent of CTA composition and monomeric activity level.An accurate molecular mechanics force field forms the basis of Molecular Dynamics simulations to obtain a realistic view of the structure and dynamics of biomolecules such as DNA. Although frequently updated to improve agreement with available experimental data, DNA force fields still rely in part on parameters introduced more than 20 years ago. We have developed an entirely new DNA force field, Tumuc1, derived from quantum mechanical calculations to obtain a consistent set of bonded parameters and partial atomic charges. The performance of the force field was extensively tested on a variety of DNA molecules. It excels in accuracy of B-DNA simulations but also performs very well on other types of DNA structures and structure formation processes such as hairpin folding, duplex formation, and dynamics of DNA-protein complexes. It can complement existing force fields in order to provide an increasingly accurate description of the structure and dynamics of DNA during simulation studies.