Enhanced microstructure and mechanical properties of ZrN-reinforced AlSi10Mg aluminum matrix composite.

Aluminum matrix composites (AMCs), incorporating Zirconium Nitride (ZrN) as reinforcing additives, demonstrate immense promise for applications in aerospace, automotive, and power generation due to their unique combination of low density, superior mechanical properties, and excellent thermal/electrical conductivity. This study explores the influence of ZrN reinforcement on the microstructure and mechanical properties of AlSi10Mg metal-matrix composites. Utilizing high-energy ball milling (HEBM) and spark-plasma sintering (SPS), ZrN/AlSi10Mg composites were synthesized, achieving nearly full density with uniform ZrN distribution, while phase and chemical transformations were not observed in the bulk composites.

[Identification of potential hazards and analysis of critical control points in cultured meat production].

The development of food technologies at the present stage is aimed at expanding the range of food raw materials, including alternative food sources. One of such sources is meat derived from in vitro stem cells or cultured meat. The stages of in vitro meat production could be divided into four blocks: preparation of raw materials, cultivation of cells in a nutrient medium, forming the final product and preparing meat for sale to the consumer.

[Comparative characteristics of the amino acid composition of protein from traditional sources and entomoprotein: calculated data].

The growth of the world population leads to an increase in demand for food consumption. Along with the projected reduction in demand for meat products, a search is underway for a new type of food ("novel food"), one of the promising options for which are insects. In 2023 the European Commission has registered flour made from house cricket (Acheta domesticus) as a "novel food" for human consumption.

[Health risk assessment associated with priority potentially hazardous chemical compounds detected in canned meat and meat-and-vegetable food for infants].

Assessment of public health safety associated with chemical contaminants consumed with food is an important component for solving the tasks of ensuring the sanitary and epidemiological well-being of the population. For these purposes, it is necessary to establish priority potentially dangerous compounds among the identified undeclared and unintended chemical contaminants for further consumers risk assessment. In conditions of unacceptable levels of health risk, it is necessary to decide whether it is advisable to develop new or change existing hygiene standards for these substances.

[The modification of methodological approaches for potential hazard identification of inadvertent chemicals in food].

The existing methodological approaches for hazard identification and selection of priority hazard contaminants in foodstuff for further health risk assessment and legislation (in case of need) do not represent the reasons of inclusion inadvertent chemical substances in a number of priority for health risk assessment. The absence both of complex assessment and potential hazard categories of contaminants do not allow to assess the urgency of health risk assessment. Thus, it's advisable to expand the existing methodological approaches with the criteria of selection of hazard inadvertent chemical substances in food.

Multi-doped apatite: Strontium, magnesium, gallium and zinc ions synergistically affect osteogenic stimulation in human mesenchymal cells important for bone tissue engineering.

Functional calcium phosphate biomaterials can be designed as carriers of a balanced mixture of biologically relevant ions able to target critical processes in bone regeneration. They hold the potential to use mechanisms very similar to growth factors naturally produced during fracture healing, while circumventing some of their drawbacks. Here we present a novel phase of carbonated-apatite containing Mg, Sr, Zn and Ga ions (HApMgSrZnGa).

Antimicrobial Polymeric Composites with Embedded Nanotextured Magnesium Oxide.

Nanotextured magnesium oxide (MgO) can exhibit both antibacterial and tissue regeneration activity, which makes it very useful for implant protection. To successfully combine these two properties, MgO needs to be processed within an appropriate carrier system that can keep MgO surface available for interactions with cells, slow down the conversion of MgO to the less active hydroxide and control MgO solubility. Here we present new composites with nanotextured MgO microrods embedded in different biodegradable polymer matrixes: poly-lactide-co-glycolide (PLGA), poly-lactide (PLA) and polycaprolactone (PCL).

Reversible Dimerization of Human Serum Albumin.

Pulsed Dipolar Spectroscopy (PDS) methods of Electron Paramagnetic Resonance (EPR) were used to detect and characterize reversible non-covalent dimers of Human Serum Albumin (HSA), the most abundant protein in human plasma. The spin labels, MTSL and OX063, were attached to Cys-34 and these chemical modifications of Cys-34 did affect the dimerization of HSA, indicating that other post-translational modifications can modulate dimer formation. At physiologically relevant concentrations, HSA does form weak, non-covalent dimers with a well-defined structure.

Simultaneous heteroepitaxial growth of SrO (001) and SrO (111) during strontium-assisted deoxidation of the Si (001) surface.

Epitaxial integration of transition-metal oxides with silicon brings a variety of functional properties to the well-established platform of electronic components. In this process, deoxidation and passivation of the silicon surface are one of the most important steps, which in our study were controlled by an ultra-thin layer of SrO and monitored by using transmission electron microscopy (TEM), electron energy-loss spectroscopy (EELS), synchrotron X-ray diffraction (XRD) and reflection high energy electron diffraction (RHEED) methods. Results revealed that an insufficient amount of SrO leads to uneven deoxidation of the silicon surface formation of pits and islands, whereas the composition of the as-formed heterostructure gradually changes from strontium silicide at the interface with silicon, to strontium silicate and SrO in the topmost layer.

Cobalt Ferrite Nanospheres as a Potential Magnetic Adsorbent for Chromium(VI) Ions.

In the present work the cobalt ferrite nanospheres (CFO NS) were prepared via one-step, templatefree solvothermal method and used as a magnetic adsorbent of chromium(VI) ions. The synthesized materials were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). The XRD results confirmed the cubic spinel structure of CFO NS while the SEM revealed sphere-like morphology with diameters of the CFO NS in the range of 100-300 nm.

Fewer Defects in the Surface Slows the Hydrolysis Rate, Decreases the ROS Generation Potential, and Improves the Non-ROS Antimicrobial Activity of MgO.

Magnesium oxide (MgO) is recognised as exhibiting a contact-based antibacterial activity. However, a comprehensive study of the impact of atomic-scale surface features on MgO's antibacterial activity is lacking. In this study, the nature and abundance of the native surface defects on different MgO powders are thoroughly investigated.

Decolonization of Intestinal Carriage of MDR/XDR Gram-Negative Bacteria with Oral Colistin in Patients with Hematological Malignancies: Results of a Randomized Controlled Trial.

Background: Intestinal colonization by MDR/XDR gram-negative bacteria leads to an increased risk of subsequent bloodstream infections (BSI) in patients receiving chemotherapy as a treatment for hematologic malignancies.

Objectives: The objective of this study was to evaluate the efficacy of oral colistin in eradicating the intestinal carriage of MDR/XDR Gram-negative bacteria in patients with hematological malignancies.

Methods: In a tertiary hematology center, adult patients with intestinal colonization by MDR/XDR Gram-negative bacteria were included in a randomized controlled trial (RCT) during a period from November 2016 to October 2017.

Plate-Like Bi4Ti3O12 Particles and their Topochemical Conversion to SrTiO3 Under Hydrothermal Conditions.

Plate-like Bi4Ti3O12 particles were synthesized using a one-step, molten-salt method from Bi2O3 and TiO2 nanopowders at 800 °C. The reaction parameters that affect the crystal structure and morphology were identified and systematically investigated. The differences between various Bi4Ti3O12 plate-like particles were examined in terms of the ferroelectric-to-paraelectric phase transition and the photocatalytic activity for the degradation of Rhodamine B under UV-Alight irradiation.

Nano-engineering the Antimicrobial Spectrum of Lantibiotics: Activity of Nisin against Gram Negative Bacteria.

Lantibiotics, bacteria-sourced antimicrobial peptides, are very good candidates for effective and safe food additives. Among them, nisin is already approved by the EU and FDA, and has been used in food preservation for the past 40 years. Now, there is a possibility and strong interest to extend its applicability to biomedicine for designing innovative alternatives to antibiotics.

Biocompatible nano-gallium/hydroxyapatite nanocomposite with antimicrobial activity.

Intensive research in the area of medical nanotechnology, especially to cope with the bacterial resistance against conventional antibiotics, has shown strong antimicrobial action of metallic and metal-oxide nanomaterials towards a wide variety of bacteria. However, the important remaining problem is that nanomaterials with highest antibacterial activity generally express also a high level of cytotoxicity for mammalian cells. Here we present gallium nanoparticles as a new solution to this problem.

Is Nano-Silver Safe within Bioactive Hydroxyapatite Composites?

Because of the abounded presence of the silver-containing products in the market and intensively studied silver-containing biomaterials in the literature, we investigated a hypothesis that stabilizing silver within bioactive hydroxyapatite composite is capable to provide safe and effective antibacterial action. For that purpose nanocomposite made of bioactive, mineral hydroxyapatite (HAp) and antibacterial silver (Ag) is studied for interactions with both, bacterial and human cells. The nanocomposite provides controlled release of Ag ions; induces severe damages in bacterial cells and is capable for strong bacteriostatic and bactericidal action.

Formation and properties of nanostructured colloidal manganese oxide particles obtained through the thermally controlled transformation of manganese carbonate precursor phase.

Structurally and morphologically different colloidal manganese oxide solids, including manganosite (MnO), bixbyite (Mn2O3) and hausmannite (Mn(2+)[Mn(3+)]2O4), were obtained through the initial biomimetically induced precipitation of a uniform, nanostructured and micron-sized rhodochrosite (MnCO3) precursor phase and their subsequent thermally controlled transformation into oxide structures in air and Ar/H2 atmospheres. The structures and morphology of the obtained precipitates were investigated using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). Their surface properties were investigated by electrophoretic mobilities (EPM) and specific surface area (SSA) measurements.

Silicon surface deoxidation using strontium oxide deposited with the pulsed laser deposition technique.

The epitaxial growth of functional oxides on silicon substrates requires atomically defined surfaces, which are most effectively prepared using Sr-induced deoxidation. The manipulation of metallic Sr is nevertheless very delicate and requires alternative buffer materials. In the present study the applicability of the chemically much more stable SrO in the process of native-oxide removal and silicon-surface stabilization was investigated using the pulsed-laser deposition technique (PLD), while the as-derived surfaces were analyzed in situ using reflection high-energy electron diffraction and ex situ using X-ray photoelectron spectroscopy, X-ray reflectivity, and atomic force microscopy.

Hydroxyapatite/gold/arginine: designing the structure to create antibacterial activity.

Antimicrobial peptides, selective antimicrobials able to "recognize" and "target" bacterial cells, are significant advancement in comparison to non-selective antimicrobials widely used in practice. The major problem of this class of macromolecules is, however, a short half-life. Starting from the key physicochemical properties of antibacterial peptides, our intention was to develop their stable analogue.

Direct observation of cationic ordering in double perovskite Sr₂FeReO₆ crystals.

Two kinds of Sr₂FeReO₆ (SFRO) samples, pristine SFRO and Re-excess SFRO, were prepared and we visualized the local atomic structure in terms of cationic ordering in the prepared SFRO samples via high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM). HAADF-STEM results demonstrated the high degree of cationic ordering maintains in both the pristine SFRO and Re-excess SFRO samples. On the other hand, defective structures such as antiphase boundary and Re-deficient phase were observed dominantly in the pristine SFRO, and thus the poor magnetic property in the pristine SFRO is attributed to those defective structures related with the frustrated Fe/Re ordering.

Photocatalytic properties of TiO2 and TiO2/Pt: a sol-precipitation, sonochemical and hydrothermal approach.

In this work we prepared TiO2 nano-powders and TiO2/Pt nano-composites via three synthesis methods (sol-precipitation, sonochemical method, hydrothermal method) starting with the same precursors and media. To evaluate and compare the physical properties of the prepared materials, X-ray diffraction analysis, BET measurements, FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS) and electron microscopy (TEM, HRTEM, SAED) were applied. The results showed changes to the TiO2 phase composition and crystallinity, the specific surface area as well as the platinum's particle shape and size, depending on the method of synthesis.

Polymorphism of LaTaTiO6.

Two polymorphs of LaTaTiO6, i.e. monoclinic and orthorhombic, were synthesized by solid-state reaction technique.

Structure of LaTi2Al9O19 and reanalysis of the crystal structure of La3Ti5Al15O37.

The non-perovskite compound LaTi(2)Al(9)O(19) was synthesized and structurally characterized by conventional X-ray powder diffraction and shown to be isostructural with SrTi(3)Al(8)O(19), as confirmed by bond-valence sum calculations. The dielectric properties of LaTi(2)Al(9)O(19) at 1 MHz were measured. The crystal structure of La(3)Ti(5)Al(15)O(37), which is referred to as the most complex structure solved ab initio from X-ray powder diffraction (XRPD) to date, is shown to be incorrect.

Crystal Structures of CaLa8Ti9O31 and Ca2La4Ti6O20 Determined from Powder Diffraction Data.

The ceramic materials of CaLa8Ti9O31 and Ca2La4Ti6O20 were synthesized using the solid-state reaction method. The crystal structures were determined from powder diffraction data using direct space methods. Like in similar compounds of the general formula AnBnO3n+2, the title compounds are composed of perovskite-like slabs, separated by oxygen-rich layers, where Ca or La occupy the A site.