Toward architecturing of metal composites by twist extrusion

The paper presents a new route for realizing the concept of architecturing of composites by severe plastic deformation. The proposed route involves multi-pass twist extrusion of a composite with fibers. The potential of the method is first illustrated by mathematical modeling and then tested through pilot processing of a composite consisting of a copper matrix and a single aluminum fiber. Metallographic analysis revealed an unexpected shape of the fiber after processing. Finite element simulations were performed to understand the evolution of the fiber shape and to optimize the processing regime for achieving improved reinforcements in twist-extruded composites.1165Ysciescopu

Modeling and characterization of texture evolution in twist extrusion

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Complex for Remote Execution of Laboratory Work on Radio Electronics

This paper presents the complex we have created for remote laboratory work on radio electronics, describes its principle of operation and features. The result of our work is a full-fledged complex with a set of laboratory works on the course of the basics of radio electronics

The Recombinases Rad51 and Dmc1 Play Distinct Roles in DNA Break Repair and Recombination Partner Choice in the Meiosis of Tetrahymena

Repair of programmed DNA double-strand breaks (DSBs) by meiotic recombination relies on the generation of flanking 3′ single-stranded DNA overhangs and their interaction with a homologous double-stranded DNA template. In various common model organisms, the ubiquitous strand exchange protein Rad51 and its meiosis-specific homologue Dmc1 have been implicated in the joint promotion of DNA–strand exchange at meiotic recombination sites. However, the division of labor between these two recombinases is still a puzzle. Using RNAi and gene-disruption experiments, we have studied their roles in meiotic recombination and chromosome pairing in the ciliated protist Tetrahymena as an evolutionarily distant meiotic model. Cytological and electrophoresis-based assays for DSBs revealed that, without Rad51p, DSBs were not repaired. However, in the absence of Dmc1p, efficient Rad51p-dependent repair took place, but crossing over was suppressed. Immunostaining and protein tagging demonstrated that only Dmc1p formed strong DSB–dependent foci on meiotic chromatin, whereas the distribution of Rad51p was diffuse within nuclei. This suggests that meiotic nucleoprotein filaments consist primarily of Dmc1p. Moreover, a proximity ligation assay confirmed that little if any Rad51p forms mixed nucleoprotein filaments with Dmc1p. Dmc1p focus formation was independent of the presence of Rad51p. The absence of Dmc1p did not result in compensatory assembly of Rad51p repair foci, and even artificial DNA damage by UV failed to induce Rad51p foci in meiotic nuclei, while it did so in somatic nuclei within one and the same cell. The observed interhomologue repair deficit in dmc1Δ meiosis is consistent with a requirement for Dmc1p in promoting the homologue as the preferred recombination partner. We propose that relatively short and/or transient Rad51p nucleoprotein filaments are sufficient for intrachromosomal recombination, whereas long nucleoprotein filaments consisting primarily of Dmc1p are required for interhomolog recombination

Extrinsic Fluorescent Dyes as Tools for Protein Characterization

Noncovalent, extrinsic fluorescent dyes are applied in various fields of protein analysis, e.g. to characterize folding intermediates, measure surface hydrophobicity, and detect aggregation or fibrillation. The main underlying mechanisms, which explain the fluorescence properties of many extrinsic dyes, are solvent relaxation processes and (twisted) intramolecular charge transfer reactions, which are affected by the environment and by interactions of the dyes with proteins. In recent time, the use of extrinsic fluorescent dyes such as ANS, Bis-ANS, Nile Red, Thioflavin T and others has increased, because of their versatility, sensitivity and suitability for high-throughput screening. The intention of this review is to give an overview of available extrinsic dyes, explain their spectral properties, and show illustrative examples of their various applications in protein characterization

A Scoping Review of Home Produced Heroin and Amphetamine Type Stimulant Substitutes: Implications for Prevention, Treatment and Policy

Several home-produced substances such as krokodil and boltushka are prevalent in many Eastern European countries. Anecdotal reports of its use have been circulating in Germany and Norway; however, this has not been confirmed. Its use has also been reported by the media in the USA, although only one confirmed report of its use exists. Home-produced drugs are associated with high levels of morbidity and a number of complex health issues such as the spread of blood borne viruses, gangrene, and internal organ damage. The high incidence of HIV rates amongst people who inject home-produced substances is a public health concern. The resulting physical health consequences of injecting these crude substances are very severe in comparison to heroin or amphetamine acquired in black markets. Due to this fact and the increased mortality associated with these substances, professionals in the area of prevention, treatment, and policy development need to be cognisant of the presentation, harms, and the dangers associated with home-produced substances globally. This scoping review aimed to examine existing literature on the subject of home-produced heroin and amphetamine-type stimulant substitutes. The review discussed the many implications such research may have in the areas of policy and practice. Data were gathered through the use of qualitative secondary resources such as journal articles, reports, reviews, case studies, and media reports. The home production of these substances relies on the utilisation of precursor drugs such as less potent stimulants, tranquillizers, analgesics, and sedatives or natural plant ingredients. The Internet underpins the facilitation of this practice as recipes, and diverted pharmaceutical sales are available widely online, and currently, ease of access to the Internet is evident worldwide. This review highlights the necessity of prevention, education, and also harm reduction related to home-produced drugs and also recommends consistent monitoring of online drug fora, online drug marketplaces, and unregulated pharmacies

Track D Social Science, Human Rights and Political Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

Comparative Analysis of Two Twist-Based SPD Processes: Elliptical Cross-Section Spiral Equal-Channel Extrusion vs. Twist Extrusion

The present paper deals with numerical comparison of two twist-based severe plastic deformation processes: (i) the elliptical cross-section spiral equal-channel extrusion (ECSEE) proposed recently as a novel process and (ii) the classical twist extrusion (TE). ECSEE was developed in attempt to process cylindrical work pieces and to generate more uniform strain distribution compared to classical TE. However, the present finite element simulations showed that twist zones used in both methods impose identical stress and strain states. Furthermore, the ability of ECSEE to treat cylindrical billets is achieved at the expense of the possibility to perform multi-pass extrusion through the twist zone and it requires higher loads for the overall process of extrusion.X1176sciescopu

Conformational analysis of MNCB (MBNC) esters and amides: Promising chiral reagents for stereoselective applications

Calculations (MM, AM1/PM3, ab initio) and DNMR experiments indicate that 2-(2'methoxy-1'-naphthyl)-3,5-dichinrobenzoic acid (MNCB) and 2'-methoxy- 1,1'-binaphthyl-2-carboxylic acid (MBNC) esters and amides exist in solution as two conformers in equilibrium: one of them (sp) has synperiplanar Ar1- Ar2 and C=O bonds, and another one (ap) has antiperiplanar bonds. Due to the close populations of the forms only apart of large shielding effects attributed to the ap form is transformed into observed high field shifts in NMR experiments. Thus, the low population of the 'ap' conformer and the low selectivity of the aryl ring anisotropic influence on the alcohol (amine) moiety are limitations of the efficiency of MNCB (MBNC) in their use as reagents for absolute stereochemisity determination of alcohols and amines by NMR. The way to increase the efficiency of this type of reagent has been revealed on the basis of these findings