Correction: Volova et al. Laser Processing of Polymer Films Fabricated from PHAs Differing in Their Monomer Composition. 2021, , 1553.

In the original publication [...

Modification of Polyhydroxyalkanoates Polymer Films Surface of Various Compositions by Laser Processing.

The results of surface modification of solvent casting films made from polyhydroxyalkanoates (PHAs) of various compositions are presented: homopolymer poly-3-hydroxybutyrate P(3HB) and copolymers comprising various combinations of 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 4-hydroxybutyrate(4HB), and 3-hydroxyhexanoate (3HHx) monomers treated with a CO laser in continuous and quasi-pulsed radiation modes. The effects of PHAs film surface modification, depending on the composition and ratio of monomers according to the results of the study of SEM and AFM, contact angles of wetting with water, adhesion and growth of fibroblasts have been revealed for the laser radiation regime used. Under continuous irradiation with vector lines, melted regions in the form of grooves are formed on the surface of the films, in which most of the samples have increased values of the contact angle and a decrease in roughness.

Biosynthesis and Properties of a P(3HB--3HV--4HV) Produced by B-10646.

Synthesis of P(3HB--3HV--4HV) copolymers by the wild-type strain B-10646 on fructose or sodium butyrate as the main C-substrate with the addition of γ-valerolactone as a precursor of 3HV and 4HV monomers was studied. Bacterial cells were cultivated in the modes that enabled production of a series of copolymers with molar fractions of 3HV (from 7.3 to 23.

Degradable Poly(3-hydroxybutyrate)-The Basis of Slow-Release Fungicide Formulations for Suppressing Potato Pathogens.

Three-component slow-release fungicide formulations with different modes of action of the active ingredients for suppressing potato pathogens were constructed for the first time. The difenoconazole, mefenoxam, prothioconazole, and azoxystrobin fungicides were embedded in the degradable polymer P(3HB)/birch wood flour blend and examined using SEM, IR spectroscopy, X-ray analysis, DTA, and DSC. Results showed that no chemical bonds were established between the components and that they were physical mixtures that had a lower degree of crystallinity compared to the initial P(3HB), which suggested different crystallization kinetics in the mixtures.

Study of the Effect of Modified Aluminum Oxide Nanofibers on the Properties of PLA-Based Films.

To find out whether AlO nanofiller is effective in improving the characteristics of polymer composites, composite polymer films based on biodegradable polylactide and epoxidized aluminum oxide nanofibers were obtained by solution casting. Surface morphology, mechanical and thermal properties of composites were studied by SEM, IR-Fourier spectroscopy, DSC and DMA. It was shown that, below and above the percolation threshold, the properties of the films differ significantly.

Bacterial Cellulose (BC) and BC Composites: Production and Properties.

The synthesis of bacterial cellulose (BC) by strain B-12068 was investigated on various C-substrates, under submerged conditions with stirring and in static surface cultures. We implemented the synthesis of BC on glycerol, glucose, beet molasses, sprat oil, and a mixture of glucose with sunflower oil. The most productive process was obtained during the production of inoculum in submerged culture and subsequent growth of large BC films (up to 0.

Production and Properties of Microbial Polyhydroxyalkanoates Synthesized from Hydrolysates of Jerusalem Artichoke Tubers and Vegetative Biomass.

One of the major challenges in PHA biotechnology is optimization of biotechnological processes of the entire synthesis, mainly by using new inexpensive carbon substrates. A promising substrate for PHA synthesis may be the sugars extracted from the Jerusalem artichoke. In the present study, hydrolysates of Jerusalem artichoke (JA) tubers and vegetative biomass were produced and used as carbon substrate for PHA synthesis.

Influence of the Filler Particles' Surface Morphology on the Polyurethane Matrix's Structure Formation in the Composite.

This article presents the surface morphology effect of silicon carbide (SiC) particles on the polyurethane binder's structure formation in a dispersed-filled composite. The difference in the morphology and surface relief of filler particles was ensured by the implementation of plasma chemical modification. As a result of this modification, the filler consisted of core-shell particles characterized by a SiC core and a carbon shell (SiC@C), as well as a carbon shell decorated with silicon nanoparticles (SiC@C/SiNP) or nanos (SiC@C/SiNW).

Properties of Degradable Polyhydroxyalkanoates (PHAs) Synthesized by a New Strain, IBP/SFU-1, from Various Carbon Sources.

The bacterial strain isolated from soil was identified as IBP/SFU-1 and investigated as a PHA producer. The strain was found to be able to grow and synthesize PHAs under autotrophic conditions and showed a broad organotrophic potential towards different carbon sources: sugars, glycerol, fatty acids, and plant oils. The highest cell concentrations (7-8 g/L) and PHA contents were produced from oleic acid (78%), fructose, glucose, and palm oil (over 80%).

Laser Processing of Polymer Films Fabricated from PHAs Differing in Their Monomer Composition.

The study reports results of using a CO-laser in continuous wave (3 W; 2 m/s) and quasi-pulsed (13.5 W; 1 m/s) modes to treat films prepared by solvent casting technique from four types of polyhydroxyalkanoates (PHAs), namely poly-3-hydroxybutyrate and three copolymers of 3-hydroxybutyrate: with 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate (each second monomer constituting about 30 mol.%).

Properties of degradable polyhydroxyalkanoates with different monomer compositions.

Purpose: To synthesize and investigate polyhydroxyalkanoates (PHAs) with different monomer composition and percentages and polymer films prepared from them.

Results: Various PHAs: homopolymer poly-3-hydroxybutyrate P(3HB) and 2-, 3-, and 4-component copolymers comprising various combinations of 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 4-hydroxybutyrate (4HB), and 3-hydroxyhexanoate (3HHx) monomers were synthesized under specialized conditions. Relationships were found between the monomer composition of PHAs and their molecular-weight and thermal properties and degree of crystallinity.

Monoclinic SmAl(BO): synthesis, structural and spectroscopic properties.

Single crystals of SmAl(BO) were synthesized by the group growth on seeds method. The crystal structure was solved using a single-crystal experiment and the purity of the bulk material was proved by the Rietveld method. This borate crystallizes in the monoclinic C2/c space group with unit-cell parameters a = 7.

Effect of the Deposition Conditions on the Anion Resin Exchange Precipitation of Indium(III) Hydroxide.

A new patented method for the synthesis of nanosized powders of indium(III) hydroxide and oxide using the strong base anion exchange resin AV-17-8 as a precipitate agent was proposed. The effect of anions of the initial indium salt and the influence of the process duration, temperature, and counterions of resin such as hydroxide or carbonate on the yield of indium(III) hydroxide during the anion resin exchange precipitation were investigated by scanning electron microscopy, electrical conductivity measurement method, and atomic absorption analysis. Based on the obtained data, the mechanism of the anion resin exchange precipitation of indium(III) hydroxide was suggested.

Structural, Electronic and Vibrational Properties of YAl(BO).

The crystal structure of YAl(BO) is obtained by Rietveld refinement analysis in the present study. The dynamical properties are studied both theoretically and experimentally. The experimental Raman and Infrared spectra are interpreted using the results of calculations within density functional theory.

The Morphology and Phenotype of Monocyte-Macrophages When Cultured on Bionanofilms Substrates with Different Surface Relief Profiles.

The effect of surface relief profiles of alkanoate-based bionanofilms to the monocyte-macrophages (MN-MPhs) from peripheral blood of patients with atherosclerosis was studied in vitro. Patients were subjected to coronary stenting. Cell morphology and phenotype (expression of CD antigens, levels of production of marker cytokines) in vitro were analyzed before and after the installation of stents.

Thermal, mechanical and biodegradation studies of biofiller based poly-3-hydroxybutyrate biocomposites.

Biodegradable poly-3-hydroxybutyrate [P(3HB)] and natural fillers - clay, peat, and birch wood flour - were used to prepare powdered composites to form pellets and granules. Pellets were produced by cold pressing of polymer and filler powder whereas granules were produced from the powders wetted with ethanol. Characterization techniques like IR spectroscopy, differential scanning calorimetry, X-ray analysis, mechanical analysis and electron microscopy were employed to study the properties of the initial P(3HB) and fillers and the composites.

Reactivity and Chemical Sintering of Carey Lea Silver Nanoparticles.

Carey Lea silver hydrosol is a rare example of very concentrated colloidal solutions produced with citrate as only protective ligands, and prospective for a wide range of applications, whose properties have been insufficiently studied up to now. Herein, the reactivity of the immobilized silver nanoparticles toward oxidation, sulfidation, and sintering upon their interaction with hydrogen peroxide, sulfide ions, and chlorocomplexes of Au(III), Pd(II), and Pt(IV) was investigated using SEM and X-ray photoelectron spectroscopy (XPS). The reactions decreased the number of carboxylic groups of the citrate-derived capping and promoted coalescence of 7 nm Ag NPs into about 40 nm ones, excluding the interaction with hydrogen peroxide.

Screening of biopolymeric materials for cardiovascular surgery toxicity-Evaluation of their surface relief with assessment of morphological aspects of monocyte/macrophage polarization in atherosclerosis patients.

The morphotypes of human macrophages (MPh) were studied in the culture on nano-structured biopolymer substrates, made from polyhydroxyalcanoates (PHAs) of five various monomer compositions, followed by the solvent evaporation. Its surface relief, which was further in direct contact with human cells was analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was shown, that the features of the micro/nano relief depend on the monomeric composition of the polymer substrates.

[The mechanisms of action of extracorporeal helium-neon laser irradiation in acute exogenous poisonings].

Extracorporeal exposure to LG-79 He-Ne laser of 12 mWt power was used in 57 patients hospitalized at the intoxication reanimation department with acute poisonings with psychotropic drugs. The clinical result was a decrease of the incidence of pneumonia in the patients with x-ray signs of venous congestion from 52% among those administered to physiochemotherapy to 24% after this treatment modality. Laser hemotherapy brought about a temporary normalization of the erythrocyte membrane permeability, which was changed biophysically by means of a diffractometer.

[The mechanism of action of low-intensity laser radiation].

The authors review primary mechanisms of action of low-intensity laser radiation used in physiotherapy. The hypothesis suggested by the authors allows one to compare efficacy of bioenergetic action of electromagnetic radiation varying in ranges, of therapeutic lasers, in particular. However, animal experiments have shown greater than bioenergetic action efficacy of the mechanism used by the nervous system in response to laser radiation.

[The use of interference currents in the rehabilitative treatment of patients with fractures of the leg bones].

Interference currents used in early treatment of patients with crural fractures accelarated recovery of the limb functions as a result of stimulation of involuntary muscular activity, reduced tissue adema and increased mobility of the ankle joint.

[Physiotherapeutic methods in the postoperative period in acute pancreatitis patients].

60 patients surgically treated for acute pancreatitis received postoperative physiotherapy which combined transcutaneous electroneurostimulation with exposure to low-energy laser. The results support the effectiveness of combined physiotherapeutic methods of general and reflex action in severe forms of acute pancreatitis because such physiotherapy early after severe forms of acute pancreatitis because such physiotherapy early after severe pancreatitis surgery promotes the decline of pathological symptoms.

[Study of excited membrane refractory period length in patients using biological feedback to an interference current device].

The authors generalized the experience of interference current apparatus application for the treatment of acute disease and trauma in the N.V. Sklifosovsky Scientific and Research Institute for Emergency Medicine (Moscow).