Исследование структуры и физико-механических свойств спеченного антифрикционного материала системы Fe-Ti

In this article are presented results of research of structure and physicomechanical properties of the sintered material of Fe-Ti system. It is shown that this material possesses high tribotechnical characteristic on comparisons with sintered iron free. In the conclusion are offered parameters of receiving this material with high physicomechanical properties

Simplified amino acid alphabets based on deviation of conditional probability from random background

The primitive data for deducing the Miyazawa-Jernigan contact energy or BLOSUM score matrix consists of pair frequency counts. Each amino acid corresponds to a conditional probability distribution. Based on the deviation of such conditional probability from random background, a scheme for reduction of amino acid alphabet is proposed. It is observed that evident discrepancy exists between reduced alphabets obtained from raw data of the Miyazawa-Jernigan's and BLOSUM's residue pair counts. Taking homologous sequence database SCOP40 as a test set, we detect homology with the obtained coarse-grained substitution matrices. It is verified that the reduced alphabets obtained well preserve information contained in the original 20-letter alphabet.Comment: 9 pages,3figure

Optimization of supply diversity for the self-assembly of simple objects in two and three dimensions

The field of algorithmic self-assembly is concerned with the design and analysis of self-assembly systems from a computational perspective, that is, from the perspective of mathematical problems whose study may give insight into the natural processes through which elementary objects self-assemble into more complex ones. One of the main problems of algorithmic self-assembly is the minimum tile set problem (MTSP), which asks for a collection of types of elementary objects (called tiles) to be found for the self-assembly of an object having a pre-established shape. Such a collection is to be as concise as possible, thus minimizing supply diversity, while satisfying a set of stringent constraints having to do with the termination and other properties of the self-assembly process from its tile types. We present a study of what we think is the first practical approach to MTSP. Our study starts with the introduction of an evolutionary heuristic to tackle MTSP and includes results from extensive experimentation with the heuristic on the self-assembly of simple objects in two and three dimensions. The heuristic we introduce combines classic elements from the field of evolutionary computation with a problem-specific variant of Pareto dominance into a multi-objective approach to MTSP.Comment: Minor typos correcte

Self-Assembling Peptide Detergents Stabilize Isolated Photosystem Ion a Dry Surface for an Extended Time

We used a class of designed peptide detergents to stabilize photosystem I (PS-I) upon extended drying under N(2) on a gold-coated-Ni-NTA glass surface. PS-I is a chlorophyll-containing membrane protein complex that is the primary reducer of ferredoxin and the electron acceptor of plastocyanin. We isolated the complex from the thylakoids of spinach chloroplasts using a chemical detergent. The chlorophyll molecules associated with the PS-I complex provide an intrinsic steady-state emission spectrum between 650 and 800 nm at −196.15 °C that reflects the organization of the pigment-protein interactions. In the absence of detergents, a large blue shift of the fluorescence maxima from approximately 735 nm to approximately 685 nm indicates a disruption in light-harvesting subunit organization, thus revealing chlorophyll−protein interactions. The commonly used membrane protein-stabilizing detergents, N-dodecyl-β-D-maltoside and N-octyl-β-D-glucoside, only partially stabilized the approximately 735-nm complex with approximately 685-nm spectroscopic shift. However, prior to drying, addition of the peptide detergent acetyl- AAAAAAK at increasing concentration significantly stabilized the PS-I complex. Moreover, in the presence of acetyl- AAAAAAK, the PS-I complex is stable in a dried form at room temperature for at least 3 wk. Another peptide detergent, acetyl-VVVVVVD, also stabilized the complex but to a lesser extent. These observations suggest that the peptide detergents may effectively stabilize membrane proteins in the solid-state. These designed peptide detergents may facilitate the study of diverse types of membrane proteins

Electron-Assisted Hopping in Two Dimensions

We have studied the non-ohmic effects in the conductivity of a two-dimensional system which undergoes the crossover from weak to strong localization with decreasing electron concentration. When the electrons are removed from equilibrium with phonons, the hopping conductivity depends only on the electron temperature. This indicates that the hopping transport in a system with a large localization length is assisted by electron-electron interactions rather than by the phonons.Comment: 5 pages, 4 figure

A Synthetic Loop Replacement Peptide That Blocks Canonical NFâ κB Signaling

Aberrant canonical NFâ κB signaling is implicated in diseases from autoimmune disorders to cancer. A major therapeutic challenge is the need for selective inhibition of the canonical pathway without impacting the many nonâ canonical NFâ κB functions. Here we show that a selective peptideâ based inhibitor of canonical NFâ κB signaling, in which a hydrogen bond in the NBD peptide is synthetically replaced by a nonâ labile bond, shows an about 10â fold increased potency relative to the original inhibitor. Not only is this molecule, NBD2, a powerful tool for dissection of canonical NFâ κB signaling in disease models and healthy tissues, the success of the synthetic loop replacement suggests that the general strategy could be useful for discovering modulators of the many proteinâ protein interactions mediated by such structures.Ein Peptidâ basierter Inhibitor für die kanonische NFâ κBâ Signalisierung, in dem eine Wasserstoffbrücke im NBDâ Peptid synthetisch durch eine nichtlabile Bindung ersetzt wurde, wirkt 10â mal stärker als der Originalinhibitor. Der Erfolg des Peptidschleifenaustauschs legt nahe, dass die Strategie nützlich sein könnte, um Modulatoren für viele durch solche Strukturen vermittelte Proteinâ Proteinâ Wechselwirkungen zu finden.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135091/1/ange201607990-sup-0001-misc_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135091/2/ange201607990.pd