Microstructure of the Advanced Titanium Alloy VT8M-1 Subjected to Rotary Swaging.

In this study, the microstructural behavior of the advanced Ti-5.7Al-3.8Mo-1.

A Novel Interaction Between RAD23A/B and Y-family DNA Polymerases.

The Y-family DNA polymerases - Pol ι, Pol η, Pol κ and Rev1 - are most well-known for their roles in the DNA damage tolerance pathway of translesion synthesis (TLS). They function to overcome replication barriers by bypassing DNA damage lesions that cannot be normally replicated, allowing replication forks to continue without stalling. In this work, we demonstrate a novel interaction between each Y-family polymerase and the nucleotide excision repair (NER) proteins, RAD23A and RAD23B.

Superplastic Behavior and Microstructural Features of the VT6 Titanium Alloy with an Ultrafine-Grained Structure during Upsetting.

In this paper, the superplastic behavior of the two-phase titanium alloy VT6 with an ultrafine-grained (UFG) structure produced by equal-channel angular pressing is examined. The deformation of specimens with a UFG structure was performed by upsetting in a temperature range of 650-750 °C and strain rate range of 1 × 10-5 × 10 s. Under these conditions, an increased strain-rate sensitivity coefficient m was observed.

Effect of the Texture of the Ultrafine-Grained Ti-6Al-4V Titanium Alloy on Impact Toughness.

In this work, the strength properties and impact toughness of the ultrafine-grained (UFG) Ti-6Al-4V titanium alloy produced by severe plastic deformation (SPD) in combination with upsetting were studied, depending on the direction of crack propagation. In the billets processed by equal-channel angular pressing (ECAP), the presence of anisotropy of ultimate tensile strength (UTS) and ductility was observed, conditioned by the formation of a metallographic and crystallographic texture. At the same time, the ECAP-processed UFG alloy exhibited satisfactory values of impact toughness, ~0.

Microstructural Features and Microhardness of the Ti-6Al-4V Alloy Synthesized by Additive Plasma Wire Deposition Welding.

Wire arc additive manufacturing (AM) is able to replace the traditional manufacturing processes of Ti alloys. At the same time, the common drawback of Ti workpieces produced by AM via wire deposition welding is the formation of a coarse-grained dendritic structure, its strong anisotropy and, consequently, lower strength as compared to a monolithic alloy. In this work, a new method is proposed for the enhancement of the strength properties of the Ti-6Al-4V alloy synthesized by AM via wire deposition welding, which involves the use of a wire with an initial ultrafine-grained (UFG) structure.

Linear and Nonlinear Elastic Properties of Polystyrene-Based Nanocomposites with Allotropic Carbon Fillers and Binary Mixtures.

We report measurements of linear and nonlinear elastic properties of polystyrene-based nanocomposites with six types of nanofillers, including single and binary mixtures of allotropic carbon nanoparticles. Composite samples were fabricated by the same technology and contained the same filler concentration (5% wt.), which allowed for a direct comparison of their properties.

Microstructure and Mechanical Properties of β-Titanium Ti-15Mo Alloy Produced by Combined Processing including ECAP-Conform and Drawing.

At present, researchers pay great attention to the development of metastable β-titanium alloys. A task of current importance is the enhancement of their strength and fatigue properties. An efficient method for increasing the strength of such alloys could be severe plastic deformation.

The B-box1 domain of PML mediates SUMO E2-E3 complex formation through an atypical interaction with UBC9.

The small, ubiquitin-like modifier SUMO is covalently attached to substrates by the enzyme UBC9. SUMO conjugation of substrates often requires an E3 ligase, which ensures substrate specificity by simultaneously binding UBC9 and the substrate. E3 SUMO ligases commonly use a RING domain to engage UBC9.

An application of the standardised reference extract quantification strategy in the quality control of ginseng infusions by liquid chromatography with mass spectrometric detection.

Introduction: Limited availability of individual standards is a bottleneck for quality control of functional foods and natural medicines. The use of standard mixtures or secondary standards is a possible alternative in this case. Earlier, an approach known as standardised reference extract (RE) strategy was introduced for HPLC-UV analysis of different plant materials; however, its application in HPLC-MS analysis has not been investigated.

Machine Learning Assisted Classification of Cell Lines and Cell States on Quantitative Phase Images.

In this report, we present implementation and validation of machine-learning classifiers for distinguishing between cell types (HeLa, A549, 3T3 cell lines) and states (live, necrosis, apoptosis) based on the analysis of optical parameters derived from cell phase images. Validation of the developed classifier shows the accuracy for distinguishing between the three cell types of about 93% and between different cell states of the same cell line of about 89%. In the field test of the developed algorithm, we demonstrate successful evaluation of the temporal dynamics of relative amounts of live, apoptotic and necrotic cells after photodynamic treatment at different doses.

Relaxation dynamics of alkyl derivatives of fluorescein MitoFluo and C-Fl in solutions with liposomes.

We present results of experimental and theoretical studies of excited state dynamics in two alkyl derivatives of fluorescein, MitoFluo and C-Fl in solutions with liposomes. The liposomes DOPC and soybeanPC + 20% Cardiolipin (Azo-Cl), modelling cellular and inner mitochondrial membranes, respectively, were used in experiments. Both types of liposomes were shown to reduce significantly the fluorescence quantum yield as compared to that of pure fluorescein derivatives in solutions, while DOPC liposomes also caused a noticeable (ca 10 nm) red shift of fluorescence maximum.

Application of digital holographic tomography in antitumor effect of cantharides complex on 4T1 breast cancer cells.

The study focuses on a methodology providing noninvasive monitoring and evaluation of the antitumor effect of traditional Chinese medicine, cantharides complex (canth), on 4T1 breast tumor cells. Digital holographic tomography (DHT) and developed data post-processing algorithms were used for quantitative estimation of changes in optical and morphological parameters of cells. We calculated and compared data on the refractive index, thickness, and projected area of 4T1 breast tumor cells in control untreated specimens and those treated with doxorubicin hydrochloride (DOX), canth, and their combinations.

Laser cladding of bioactive glass coating on pure titanium substrate with highly refined grain structure.

Free from toxic elements biomaterial potentially applicable for load bearing biomedical implants was obtained for the first time by laser cladding of S520 bioactive glass onto ultrafine-grained commercially pure titanium. The cladding process affected the refined structure of the substrate inducing martensitic transformation near its surface. The α' acicular martensite gradually passes into relatively large grains with increasing distance from the substrate surface, which subsequently are transformed into smaller grains of about 2 μm in diameter.

Persistent growth of microtubules at low density.

Microtubules (MTs) often form a polarized array with minus ends anchored at the centrosome and plus ends extended toward the cell margins. Plus ends display behavior known as dynamic instability-transitions between rapid shortening and slow growth. It is known that dynamic instability is regulated locally to ensure entry of MTs into nascent areas of the cytoplasm, but details of this regulation remain largely unknown.

Polystyrene-Based Nanocomposites with Different Fillers: Fabrication and Mechanical Properties.

The paper presents a comprehensive analysis of the elastic properties of polystyrene-based nanocomposites filled with different types of inclusions: small spherical particles (SiO and AlO), alumosilicates (montmorillonite, halloysite natural tubules and mica), and carbon nanofillers (carbon black and multi-walled carbon nanotubes). Block samples of composites with different filler concentrations were fabricated by melt technology, and their linear and non-linear elastic properties were studied. The introduction of more rigid particles led to a more profound increase in the elastic modulus of a composite, with the highest rise of about 80% obtained with carbon fillers.

Eco-friendly synthesis of fused pyrano[2,3-]pyrans ammonium acetate-mediated formal oxa-[3 + 3]cycloaddition of 4-chromene-3-carbaldehydes and cyclic 1,3-dicarbonyl compounds.

Various substituted polycyclic pyrano[2,3-]pyrans were synthesized the condensation of 4-chromene-3-carbaldehydes and their areno-condensed analogues with hetero- and carbocyclic 1,3-dicarbonyl compounds in acetic acid. Ammonium acetate was used as a green catalyst for the reaction. The process also involves the subsequent Knoevenagel condensation and 6π-electrocyclization of the 1-oxatriene intermediates formed.

Molybdenum Disulfide Surface Modification of Ultrafine-Grained Titanium for Enhanced Cellular Growth and Antibacterial Effect.

The commercially pure Ti (CP Ti) and equal-channel angular pressing (ECAP) processed Ti can contribute to the downsizing of medical devices with their superior mechanical properties and negligible toxicity. However, the ECAP-processed pure Ti has the risk of bacterial infection. Here, the coarse- and ultrafine-grained Ti substrates were surface-modified with molybdenum disulfide (MoS) to improve the cell proliferation and growth with antibacterial effect for further dental applications.

Stimulation of microtubule-based transport by nucleation of microtubules on pigment granules.

Microtubule (MT)-based transport can be regulated through changes in organization of MT transport tracks, but the mechanisms that regulate these changes are poorly understood. In melanophores, aggregation of pigment granules in the cell center involves their capture by the tips of MTs growing toward the cell periphery, and granule aggregation signals facilitate capture by increasing the number of growing MT tips. This increase could be explained by stimulation of MT nucleation either on the centrosome or on the aggregate of pigment granules that gradually forms in the cell center.

Engineered Tug-of-War Between Kinesin and Dynein Controls Direction of Microtubule Based Transport In Vivo.

Bidirectional transport of membrane organelles along microtubules (MTs) is driven by plus-end directed kinesins and minus-end directed dynein bound to the same cargo. Activities of opposing MT motors produce bidirectional movement of membrane organelles and cytoplasmic particles along MT transport tracks. Directionality of MT-based transport might be controlled by a protein complex that determines which motor type is active at any given moment of time, or determined by the outcome of a tug-of-war between MT motors dragging cargo organelles in opposite directions.

Regulation of microtubule-based transport by MAP4.

Microtubule (MT)-based transport of organelles driven by the opposing MT motors kinesins and dynein is tightly regulated in cells, but the underlying molecular mechanisms remain largely unknown. Here we tested the regulation of MT transport by the ubiquitous protein MAP4 using Xenopus melanophores as an experimental system. In these cells, pigment granules (melanosomes) move along MTs to the cell center (aggregation) or to the periphery (dispersion) by means of cytoplasmic dynein and kinesin-2, respectively.

Nanostructured severe plastic deformation processed titanium for orthodontic mini-implants.

Titanium mini-implants have been successfully used as anchorage devices in Orthodontics. Commercially pure titanium (cpTi) was recently replaced by Ti-6Al-4V alloy as the mini-implant material base due to the higher strength properties of the alloy. However, the lower corrosion resistance and the lower biocompatibility have been lowering the success rate of Ti-6Al-4V mini-implants.

Stimulation of the CLIP-170--dependent capture of membrane organelles by microtubules through fine tuning of microtubule assembly dynamics.

Cytoplasmic microtubules (MTs) continuously grow and shorten at their free plus ends, a behavior that allows them to capture membrane organelles destined for MT minus end-directed transport. In Xenopus melanophores, the capture of pigment granules (melanosomes) involves the +TIP CLIP-170, which is enriched at growing MT plus ends. Here we used Xenopus melanophores to test whether signals that stimulate minus end MT transport also enhance CLIP-170-dependent binding of melanosomes to MT tips.

CK1 activates minus-end-directed transport of membrane organelles along microtubules.

Microtubule (MT)-based organelle transport is driven by MT motor proteins that move cargoes toward MT minus-ends clustered in the cell center (dyneins) or plus-ends extended to the periphery (kinesins). Cells are able to rapidly switch the direction of transport in response to external cues, but the signaling events that control switching remain poorly understood. Here, we examined the signaling mechanism responsible for the rapid activation of dynein-dependent MT minus-end-directed pigment granule movement in Xenopus melanophores (pigment aggregation).

Melanophores for microtubule dynamics and motility assays.

Microtubules (MTs) are cytoskeletal structures essential for cell division, locomotion, intracellular transport, and spatial organization of the cytoplasm. In most interphase cells, MTs are organized into a polarized radial array with minus-ends clustered at the centrosome and plus-ends extended to the cell periphery. This array directs transport of organelles driven by MT-based motor proteins that specifically move either to plus- or to minus-ends.