Pressure-dependent 13C chemical shifts in proteins: Origins and applications

Pressure-dependent (13)C chemical shifts have been measured for aliphatic carbons in barnase and Protein G. Up to 200 MPa (2 kbar), most shift changes are linear, demonstrating pressure-independent compressibilities. CH(3), CH(2) and CH carbon shifts change on average by +0.23, -0.09 and -0.18 ppm, respectively, due to a combination of bond shortening and changes in bond angles, the latter matching one explanation for the gamma-gauche effect. In addition, there is a residue-specific component, arising from both local compression and conformational change. To assess the relative magnitudes of these effects, residue-specific shift changes for protein G were converted into structural restraints and used to calculate the change in structure with pressure, using a genetic algorithm to convert shift changes into dihedral angle restraints. The results demonstrate that residual (13)C alpha shifts are dominated by dihedral angle changes and can be used to calculate structural change, whereas (13)C beta shifts retain significant dependence on local compression, making them less useful as structural restraints

Overview: Computer vision and machine learning for microstructural characterization and analysis

The characterization and analysis of microstructure is the foundation of microstructural science, connecting the materials structure to its composition, process history, and properties. Microstructural quantification traditionally involves a human deciding a priori what to measure and then devising a purpose-built method for doing so. However, recent advances in data science, including computer vision (CV) and machine learning (ML) offer new approaches to extracting information from microstructural images. This overview surveys CV approaches to numerically encode the visual information contained in a microstructural image, which then provides input to supervised or unsupervised ML algorithms that find associations and trends in the high-dimensional image representation. CV/ML systems for microstructural characterization and analysis span the taxonomy of image analysis tasks, including image classification, semantic segmentation, object detection, and instance segmentation. These tools enable new approaches to microstructural analysis, including the development of new, rich visual metrics and the discovery of processing-microstructure-property relationships.Comment: submitted to Materials and Metallurgical Transactions

D * polarization vs. R D(∗) anomalies in the leptoquark models

Polarization measurements in B → D(*)Ƭν̅ are useful to check consistency in new physics explanations for the RD and RD* anomalies. In this paper, we investigate the D* and Ƭ polarizations and focus on the new physics contributions to the fraction of a longitudinal D* polarization (F D*/L ), which is recently measured by the Belle collaboration F D*/L = 0:60 ± 0:09, in model-independent manner and in each single leptoquark model (R2, S1 and U1) that can naturally explain the RD(*) anomalies. It is found that B(B+/c → Ƭ⁺ν) severely restricts deviation from the Standard Model (SM) prediction of F D*/L,SM = 0:46 ± 0:04 in the leptoquark models: [0:43; 0:44], [0:42; 0:48], and [0:43; 0:47] are predicted as a range of F D*/L for the R2, S1, and U1 leptoquark models, respectively, where the current data of RD(*) is satised at 1 σ level. It is also shown that the Ƭ polarization observables can much deviate from the SM predictions. The Belle II experiment, therefore, can check such correlations between RD(*) and the polarization observables, and discriminate among the leptoquark models

Synthesis, Stability, and Crystal Structure of an Azulenium Cation Containing an Adamantyl Group

This is the pre-peer reviewed version of the following article: EUROPEAN JOURNAL OF ORGANIC CHEMISTRY. 2008(31):5301-5307 (2008), which has been published in final form at doi:10.1002/ejoc.200800700.ArticleEUROPEAN JOURNAL OF ORGANIC CHEMISTRY. 2008(31):5301-5307 (2008)journal articl

Modern Russian informational technologies of enterprise management. Platform 1C

The history of the development of the 1C program is briefly described. The topic of licensing and product safety was touched upon. Little is said about the corporate line and the new direction of 1C: EnterpriseDevelopmentTools. Also get acquainted with the products of 1C:ManufacturingEnterpriseManagement and 1C:EnterpriseResourcesPlanning

The Effect of Shear on Phase-Ordering Dynamics with Order-Parameter-Dependent Mobility: The Large-n Limit

The effect of shear on the ordering-kinetics of a conserved order-parameter system with O(n) symmetry and order-parameter-dependent mobility \Gamma({\vec\phi}) \propto (1- {\vec\phi} ^2/n)^\alpha is studied analytically within the large-n limit. In the late stage, the structure factor becomes anisotropic and exhibits multiscaling behavior with characteristic length scales (t^{2\alpha+5}/\ln t)^{1/2(\alpha+2)} in the flow direction and (t/\ln t)^{1/2(\alpha+2)} in directions perpendicular to the flow. As in the \alpha=0 case, the structure factor in the shear-flow plane has two parallel ridges.Comment: 6 pages, 2 figure

Non-equilibrium interface equations: An application to thermo-capillary motion in binary systems

Interface equations are derived for both binary diffusive and binary fluid systems subjected to non-equilibrium conditions, starting from the coarse-grained (mesoscopic) models. The equations are used to describe thermo-capillary motion of a droplet in both purely diffusive and fluid cases, and the results are compared with numerical simulations. A mesoscopic chemical potential shift, owing to the temperature gradient, and associated mesoscopic corrections involved in droplet motion are elucidated.Comment: 12 pages; Latex, revtex, ap

Stability of a Nonequilibrium Interface in a Driven Phase Segregating System

We investigate the dynamics of a nonequilibrium interface between coexisting phases in a system described by a Cahn-Hilliard equation with an additional driving term. By means of a matched asymptotic expansion we derive equations for the interface motion. A linear stability analysis of these equations results in a condition for the stability of a flat interface. We find that the stability properties of a flat interface depend on the structure of the driving term in the original equation.Comment: 14 pages Latex, 1 postscript-figur

Phase Separation Kinetics in a Model with Order-Parameter Dependent Mobility

We present extensive results from 2-dimensional simulations of phase separation kinetics in a model with order-parameter dependent mobility. We find that the time-dependent structure factor exhibits dynamical scaling and the scaling function is numerically indistinguishable from that for the Cahn-Hilliard (CH) equation, even in the limit where surface diffusion is the mechanism for domain growth. This supports the view that the scaling form of the structure factor is "universal" and leads us to question the conventional wisdom that an accurate representation of the scaled structure factor for the CH equation can only be obtained from a theory which correctly models bulk diffusion.Comment: To appear in PRE, figures available on reques