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Defence policy and related activities, such as territorial defence and comprehensive defence, are considered a matter of national priority and consensus in Estonia since its restoration of independence in 1991. The actual meaning and its content have depended on numerous linguistic and cultural factors. Educational traditions and alliance relations have played an important role as well. In some cases, changes in actual defence policy content first required an ability to change military terminology and outlook. The current study analyses the meaning of territorial defence, comprehensive defence and total defence in official documents and based on focus group interviews among officers of BDCOL and EMA.

In this paper, we present the results of in situ temperature measurements of resistivity for some amorphous or partially crystalling Heusler alloy (HA) films: Co2CrAl, Co2MnGa, and off-stoichiometric Ni2Mn1+xSn1-x, Ni2Mn1+xGa1-x that are known to exhibit half-metallic properties and martensitic transformations, respectively. From resistivity ρ versus T characteristics we distinguish various stages of chemical and structural ordering in the films. They appear to be quite distinct in both systems investigated due to differences in their electronic structure. The resistivity results are compared with magnetic characteristics for Co2 MnGa with a high Curie temperature. High-temperature resistivity measurement is a sensitive tool for tracing the chemical and structural ordering in HA films. [ABSTRACT FROM AUTHOR]

The influence of an ultrathin cobalt layer at permalloy/gold interfaces in Au/Ni80Fe20/Au sandwiches and spin-valve (Ni80Fe20/Au/Co/Au)N multilayers on their magnetic and magnetotransport properties is investigated. We show that an effective magnetic anisotropy of Co/Ni80Fe20/Co hybrid structures sandwiched between Au layers can be easily varied by the thickness adjustment of Co and Ni80Fe20 layers. We also show that changes of the anisotropy are mainly determined by the Co layer deposited on Au. On the other hand, the influence of Co layer deposited on Ni80Fe20 is relatively small. The use of hybrid layers in the spin valve MLs with alternating easy plane and perpendicular anisotropy in consecutive ferromagnetic layers leads to significant changes of their magnetoresistance effect. [ABSTRACT FROM AUTHOR]

The effect of roller burnishing on Vickers’ hardness and positron lifetimes in the AZ91HP magnesium alloy was studied. The microhardness increases with an increase in the burnishing force and with a decrease in the feed. The comparison of various methods of analysis of positron annihilation lifetime (PAL) spectra allowed identification of two components, which are related to solute-vacancy complexes and vacancy clusters, respectively. It was found that the increase in microhardness was related to the increase in the concentration of vacancy clusters.

Ferromagnetic resonance has been investigated in Ni2MnSn Heusler alloy films. The films were deposited at 673 < T < 723 K on MgO(001) substrates by means of magnetron sputtering. X-ray diffraction confirmed that the films were epitaxial. The films had magnetic parameters typical of bulk Ni2MnSn with L21 structural order. From angular dependences of the resonance field and the ferromagnetic resonance linewidth the intrinsic Gilbert contribution and extrinsic contribution to the ferromagnetic resonance linewidth due to two-magnon scattering were separated. Our data indicate a room temperature Gilbert damping of 0.007, which is comparable to that of half-metallic Heusler alloy. Surface roughness is responsible for a substantial extrinsic two-magnon contribution to the linewidth of the order of 50-300 Oe in these epitaxial soft magnetic Heusler alloy films. The spin wave stiffness of D = 70-100 meVÅ2 is one of the lowest for the known Heusler alloy. [ABSTRACT FROM AUTHOR]

This article introduces an algorithm for determining optimal parameters of a technological process. The objective function is the processing time of operations (efficiency) at the constraint of quality requirements of finish according to the designer specification. The problem of selecting a correct combination of processing parameters may only be solved when the cause-and-effect relationship between the finish quality and the machining settings is known. If the process considered for optimisation is repeatable, it appears economically viable to invest resources in the development of a model that would describe these relationships. To this end, we propose employing the artificial neural network trained on the progressions obtained from the tests. In the second stage, the Multiple-Input-Multiple-Output (MIMO) system, capable of representing relationships of nonlinear nature, was implemented for the optimisation of the objective function. The paper presents the application of the developed algorithm in determination of optimal parameters for the roller burnishing process of surface treatment. A technologist/software user defines the range of acceptable surface finishes. The optimisation algorithm determines a set of modifiable parameters that ensure minimal processing time at a specified surface finish requirements constraint.

The purpose of this study was to design and test an intelligent computer software developed with the purpose of increasing average productivity of milling not compromising the design features of the final product. The developed system generates optimal milling parameters based on the extent of tool wear. The introduced optimisation algorithm employs a multilayer model of a milling process developed in the artificial neural network. The input parameters for model training are the following: cutting speed vc, feed per tooth fz and the degree of tool wear measured by means of localised flank wear (VB3). The output parameter is the surface roughness of a machined surface Ra. Since the model in the neural network exhibits good approximation of functional relationships, it was applied to determine optimal milling parameters in changeable tool wear conditions (VB3) and stabilisation of surface roughness parameter Ra. Our solution enables constant control over surface roughness parameters and productivity of milling process after each assessment of tool condition. The recommended parameters, i.e. those which applied in milling ensure desired surface roughness and maximal productivity, are selected from all the parameters generated by the model. The developed software may constitute an expert system supporting a milling machine operator. In addition, the application may be installed on a mobile device (smartphone), connected to a tool wear diagnostics instrument and the machine tool controller in order to supply updated optimal parameters of milling. The presented solution facilitates tool life optimisation and decreasing tool change costs, particularly during prolonged operation.

Abstract Background Complement C2 deficiency is the most common genetically determined complete complement deficiency and is associated with a number of diseases. Most prominent are the associations with recurrent serious infections in young children and the development of systemic lupus erythematosus (SLE) in adults. The links with these diseases reflect the important role complement C2 plays in both innate immunity and immune tolerance. Infusions with normal fresh frozen plasma for the treatment of associated disease have demonstrated therapeutic effects but so far protein replacement therapy has not been evaluated. Results Human complement C2 was cloned and expressed in a mammalian cell line. The purity of recombinant human C2 (rhC2) was greater than 95% and it was characterized for stability and activity. It was sensitive to C1s cleavage and restored classical complement pathway activity in C2-deficient serum both in a complement activation ELISA and a hemolytic assay. Furthermore, rhC2 could increase C3 fragment deposition on the human pathogen Streptococcus pneumoniae in C2-deficient serum to levels equal to those with normal serum. Conclusions Taken together these data suggest that recombinant human C2 can restore classical complement pathway activity and may serve as a potential therapeutic for recurring bacterial infections or SLE in C2-deficient patients.

Meteorites are a unique source of geological information about our early Solar System and the difference between planets and asteroids. In this study, meteorite Ribbeck (2024 BX1, SAR 2736) from the recently fallen asteroid (21.01.2024), collected right after the fall, was investigated. This meteorite is classified as a coarse-grained brecciated aubrite. The main mineral phases are enstatite, albite, and forsterite. X-ray structural analysis and Raman Spectroscopy indicate its complex metamorphic history, starting with magmatic crystallization and following metamorphic evolution (e.g., impacting). Energy-dispersive. X-ray spectroscopy (EDS) confirms the presence of unusual minerals such as oldhamite, brezinanite (daubréelite, zolenskyite), wassonite/heideite, and alabandite, that formed under highly reductive conditions, with oxygen fugacity ΔIW (logfO 2 ) in a range of -5 to -7. Similar conditions can be found on the Mercury or the Asteroid 3103 Eger. Magnetic measurements confirm that the primary magnetic components in the meteorite are accessory minerals - sulphides and metallic nodules., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Research on titanium nanotubes modified with metal sulfides, particularly bismuth sulfide (Bi 2 S 3 ), aims to create heterostructures that efficiently absorb sunlight and then separate photogenerated charge carriers, thereby enhancing the energy conversion efficiency. This study shows a key role of solvent used for sulfide and bismuth salt solutions used during successive ionic layer adsorption and reaction (SILAR) onto the morphology, structure, and photoresponse of the heterojunction where one element is represented by semitransparent titania nanotubes (gTiNT) and the second is Bi 2 S 3 . Using 2-methoxyethanol and methanol during SILAR, results in remarkably photoactive 3D heterostructure and recorded photocurrents were 44 times higher compared to bare titania nanotubes. Additionally, methanol- and 2-methoxyethanol-based processing allowed uniform deposition of the sulfide, which was not reached for other solvents. XPS studies not only confirm formation of bismuth sulfides but also indicate that Bi x Ti y O z compound can arise that can affect both stability and photoactivity of the electrode material.

Flexoelectricity, an intrinsic property observed in materials under nonuniform deformation, entails a coupling between polarization and strain gradients. Recent catalyst advancements have reignited interest in flexoelectricity, particularly at the nanoscale, where pronounced strain gradients promote robust flexoelectric effects. This paper comprehensively examines flexoelectricity, encompassing methodologies for precise measurement, elucidating its distinctions from related phenomena, and exploring its potential applications in augmenting catalytic properties. So far, the greatest potentials are based on lead strontium titanate (PST) and other metallic titanates such as titania (TiO 2 ), strontium titanate (STO), barium strontium titanate (BST) sulfates (MoS 2 , ZnS) and halide perovskites (with archetype XPbI 3 ). This review explores the promise of flexoelectric properties in addressing material and photocatalytic challenges, such as charge carrier recombination and ineffective surface charge separation. Additionally, it sheds light on the synergy with emerging paradigms like photo-flexo catalysis and synergistic flexo-piezo catalysis, specifically focusing on selective chemical transformations like green hydrogen production. Current limitations related to the usage of photoflexoelectricity for photocatalysis are mostly the stability of the used substance (susceptibility to photodegradation) or the voltage values, which represent the inferior potential for specific practical applications. This work underscores the indispensable role of flexoelectricity in catalysis and its capacity to steer future research and technological advancement., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Polydopamine (PDA) stands as a versatile material explored in cancer nanomedicine for its unique properties, offering opportunities for multifunctional drug delivery platforms. This study explores the potential of utilizing a one-pot synthesis to concurrently integrate Fe, Gd and Mn ions into porous PDA-based theranostic drug delivery platforms called Ferritis, Gadolinis and Manganis, respectively. Our investigation spans the morphology, magnetic properties, photothermal characteristics and cytotoxicity profiles of those potent nanoformulations. The obtained structures showcase a spherical morphology, robust magnetic response and promising photothermal behaviour. All of the presented nanoparticles (NPs) display pronounced paramagnetism, revealing contrasting potential for MRI imaging. Relaxivity values, a key determinant of contrast efficacy, demonstrated competitive or superior performance compared to established, used contrasting agents. These nanoformulations also exhibited robust photothermal properties under near infra-red irradiation, showcasing their possible application for photothermal therapy of cancer. Our findings provide insights into the potential of metal-doped PDA NPs for cancer theranostics.

Cellulose acetate membranes exhibit a potential to be applied in hemodialysis. However, their performance is limited by membrane fouling and a lack of antibacterial properties. In this research, copper oxide (I) nanoparticles were fabricated in situ into a cellulose acetate matrix in the presence of polyvinylpyrrolidone (pore-forming agent) and sulfobetaine (stabilising agent) to reduce the leakage of copper ions from nano-enhanced membranes. The influence of nanoparticles on the membrane structure and their antibacterial and antifouling properties were investigated. The results showed that incorporating Cu 2 O NPs imparted significant antibacterial properties against Staphylococcus aureus and fouling resistance under physiological conditions. The Cu 2 O NPs-modified membrane could pave the way for potential dialysis applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Grzegorz Nowaczyk reports financial support was provided by the National Center for Research and Development. Katarzyna Staszak reports financial support was provided by the Ministry of Education and Science of the Republic of Poland. The other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The evolving field of photocatalysis requires the development of new functional materials, particularly those suitable for large-scale commercial systems. One particularly promising approach is the creation of hybrid organic/inorganic materials. Despite being extensively studied, materials such as polydopamine (PDA) and titanium oxide continue to show significant promise for use in such applications. Nitrogen-doped titanium oxide and free-standing PDA films obtained at the air/water interface are particularly interesting. This study introduces a straightforward and reproducible approach for synthesizing a novel class of large-scale multilayer nanocomposites. The method involves the alternate layering of high-quality materials at the air/water interface combined with precise atomic layer deposition techniques, resulting in a gradient nitrogen doping of titanium oxide layers with exceptionally sharp oxide/polymer interfaces. The analysis confirmed the presence of nitrogen in the interstitial and substitutional sites of the TiO 2 lattice while maintaining the 2D-like structure of the PDA films. These chemical and structural characteristics translate into a reduction of the band gap by over 0.63 eV and an increase in the photogenerated current by over 60% compared with pure amorphous TiO 2 . Furthermore, the nanocomposites demonstrate excellent stability during the 1 h continuous photocurrent generation test.

Cancer remains a leading cause of mortality worldwide, necessitating the development of innovative therapeutic approaches. Nanoparticle-based drug delivery systems have garnered significant interest due to their multifunctionality, offering the potential to enhance cancer treatment efficacy and improve patient tolerability. Membrane-coated drug delivery systems hold great potential for enhancing the therapeutic outcome of nanoparticle-based anticancer therapies. In this study, we report the synthesis of multifunctional iron-functionalized mesoporous polydopamine nanoparticles (MPDAFe NPs). These nanoformulations demonstrate substantial potential for combining efficient drug delivery and magnetic resonance imaging (MRI) and showcase the advantages of biomimetic coating with tumor cell-derived membranes. This coating confers prolonged circulation and improved the targeting capabilities of the nanoparticles. Furthermore, comprehensive biosafety evaluations reveal negligible toxicity to normal cells, while the combined chemo- and phototherapy exhibited significant cytotoxicity towards cancer cells. Additionally, the photothermal effect evaluation highlights the enhanced cytotoxicity achieved through laser irradiation, showcasing the synergistic effects of the nanomaterials and photothermal therapy. Importantly, our chemotherapeutic effect evaluation demonstrates the superior efficacy of doxorubicin-loaded MPDAFe@Mem NPs (cancer cell membrane-coated MPDAFe NPs) in inhibiting cancer cell viability and proliferation, surpassing the potency of free doxorubicin. This study comprehensively investigates theranostic, membrane-coated drug delivery systems, underlining their potential to increase the efficacy of cancer treatment strategies. The multifunctional nature of the iron-functionalized polydopamine nanoparticles allows for efficient drug delivery and imaging capabilities, while the biomimetic coating enhances their biocompatibility and targeting ability. These findings contribute valuable insights towards the development of advanced nanomedicine for improved cancer therapeutics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Topographical cues on materials can manipulate cellular fate, particularly for neural cells that respond well to such cues. Utilizing biomaterial surfaces with topographical features can effectively influence neuronal differentiation and promote neurite outgrowth. This is crucial for improving the regeneration of damaged neural tissue after injury. Here, we utilized groove patterns to create neural conduits that promote neural differentiation and axonal growth. We investigated the differentiation of human neural stem cells (NSCs) on silicon dioxide groove patterns with varying height-to-width/spacing ratios. We hypothesize that NSCs can sense the microgrooves with nanoscale depth on different aspect ratio substrates and exhibit different morphologies and differentiation fate. A comprehensive approach was employed, analyzing cell morphology, neurite length, and cell-specific markers. These aspects provided insights into the behavior of the investigated NSCs and their response to the topographical cues. Three groove-pattern models were designed with varying height-to-width/spacing ratios of 80, 42, and 30 for groove pattern widths of 1 μm, 5 μm, and 10 μm and nanoheights of 80 nm, 210 nm, and 280 nm. Smaller groove patterns led to longer neurites and more effective differentiation towards neurons, whereas larger patterns promoted multidimensional differentiation towards both neurons and glia. We transferred these cues onto patterned polycaprolactone (PCL) and PCL-graphene oxide (PCL-GO) composite 'stamps' using simple soft lithography and reproducible extrusion 3D printing methods. The patterned scaffolds elicited a response from NSCs comparable to that of silicon dioxide groove patterns. The smallest pattern stimulated the highest neurite outgrowth, while the middle-sized grooves of PCL-GO induced effective synaptogenesis. We demonstrated the potential for such structures to be wrapped into tubes and used as grafts for peripheral nerve regeneration. Grooved PCL and PCL-GO conduits could be a promising alternative to nerve grafting., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

A series of {V 12 }-nuclearity polyoxovanadate cages covalently functionalized with one or sandwiched by two phthalocyaninato (Pc) lanthanide (Ln) moieties via V-O-Ln bonds were prepared and fully characterized for paramagnetic Ln = Sm III -Er III and diamagnetic Ln = Lu III , including Y III . The LnPc-functionalized {V 12 O 32 } cages with fully oxidized vanadium centers in the ground state were isolated as ( n Bu 4 N) 3 [HV 12 O 32 Cl(LnPc)] and ( n Bu 4 N) 2 [HV 12 O 32 Cl(LnPc) 2 ] compounds. As corroborated by a combined experimental (EPR, DC and AC SQUID, laser photolysis transient absorption spectroscopy, and electrochemistry) and computational (DFT, MD, and model Hamiltonian approach) methods, the compounds feature intra- and intermolecular electron transfer that is responsible for a partial reduction at V(3d) centers from V V to V IV in the solid state and at high sample concentrations. The effects are generally Ln dependent and are clearly demonstrated for the ( n Bu 4 N) 3 [HV 12 O 32 Cl(LnPc)] representative with Ln = Lu III or Dy III . Intramolecular charge transfer takes place for Ln = Lu III and occurs from a Pc ligand via the Ln center to the {V 12 O 32 } core of the same molecule, whereas for Ln = Dy III , only intermolecular charge transfer is allowed, which is realized from Pc in one molecule to the {V 12 O 32 } core of another molecule usually via the n Bu 4 N + countercation. For all Ln but Dy III , two of these phenomena may be present in different proportions. Besides, it is demonstrated that ( n Bu 4 N) 3 [HV 12 O 32 Cl(DyPc)] is a field-induced single molecule magnet with a maximal relaxation time of the order 10 -3 s. The obtained results open up the way to further exploration and fine-tuning of these three modular molecular nanocomposites regarding tailoring and control of their Ln-dependent charge-separated states (induced by intramolecular transfer) and relaxation dynamics as well as of electron hopping between molecules. This should enable us to realize ultra-sensitive polyoxometalate powered quasi-superconductors, sensors, and data storage/processing materials for quantum technologies and neuromorphic computing.

Novel multifunctional ZnO:Gd@ZIF-8 hybrid inorganic-organic nanocomposites with tunable luminescent-magnetic performance were successfully fabricated using wet chemistry synthesis routes. Physico-chemical characterization including crystal structure, phase compositions, morphology, surface properties, as well as photoluminescent and magnetic characteristics was performed using powder X-ray diffraction (XRD), FT-IR analysis, transmission and scanning electron microscopies (TEM/SEM), N 2 adsorption/desorption, SQUID magnetometer, and photoluminescence spectroscopy. The biological studies of obtained materials, such as cytotoxicity profile and in vitro MRI imaging also investigated for potential use as contrast agents. Results showed that the doping with Gd 3+ in a broad concentration range and the presence of ZIF-8 layer on ZnO affect the physico-chemical properties of the obtained composites. The obtained porous ZnO:Gd@ZIF-8 composites were highly crystalline with a large surface area. The XRD study indicated the formation of hexagonal wurtzite structure for ZnO and ZnO:Gd 3+ (1-5 at.%). Luminescent studies showed, that ZnO is an ideal matrix for the incorporation of Gd 3+ ions in a broad concentration range with efficient green luminescence. The PL intensity reached the maximum up to 5 at.% of Gd 3+ . The zeta potential values indicated the good stability of obtained nanoparticles. Proposed new materials with paramagnetic behavior and outstanding MR imaging capability could be used as potential contrast agents for magnetic resonance imaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Implant-related microbial infection is a challenging clinical problem, and its treatment requires efficient eradication of the biofilm from the implant surface. Near-infrared (NIR)-responsive strategies are proposed as an emerging efficient antibacterial therapy. However, the utilization of photosensitizers or photocatalytic/photothermal nanomaterials in the available approach likely induces high potential risks of interfacial deterioration and biosafety compromise. Herein, a TiO 2 /TiO 2- x metasurface with potent NIR-responsive antibacterial activity is produced on a Ti alloy implant by a newly invented topochemical conversion-based alkaline-acid bidirectional hydrothermal method (aaBH). Electromagnetic simulations prove that NIR absorption and near-field distribution of the metasurface can be tuned by the dimension and arrangement of the nanostructural unit. Promising antibacterial efficacy is proved by both in vitro and in vivo tests, with low-power NIR irradiation for 10 min. Besides, the designed nanostructure in the metasurface itself also shows excellence in enhancing the adhesion-related gene expression of human gingival fibroblasts that are exposed to 10 min of NIR irradiation, proving the potent nanostructure-induced biological effects. This work provides a biosafe and upscalable metasurfacing approach with extraordinary capacity of manipulating light adsorption, photocatalysis, and biological properties., (© 2021 Wiley-VCH GmbH.)

Nanoscale manipulation of material surfaces can create extraordinary properties, holding great potential for modulating the implant-bio interface for enhanced performance. In this study, a green, simple and biocompatible nanosurfacing approach based on weak alkalinity-activated solid-state dewetting (AAD) was for the first time developed to nano-manipulate the Ti6Al4V surface by atomic self-rearrangement. AAD treatment generated quasi-periodic titanium oxide nanopimples with high surface energy. The nanopimple-like nanostructures enhanced the osteogenic activity of osteoblasts, facilitated M2 polarization of macrophages, and modulated the cross-talk between osteoblasts and macrophages, which collectively led to significant strengthening of in vivo bone-implant interfacial bonding. In addition, the titanium oxide nanopimples strongly adhered to the Ti alloy, showing resistance to tribocorrosion damage. The results suggest strong nano-bio interfacial effects, which was not seen for the control Ti alloy processed through traditional thermal oxidation. Compared to other nanostructuring strategies, the AAD technique shows great potential to integrate high-performance, functionality, practicality and scalability for surface modification of medical implants.

The influence of magnetite nanoparticles coated with poly(acrylic acid) (Fe 3 O 4 @PAA NPs) on the organization of block copolymer thin films via a self-assembly process was investigated. Polystyrene- b -poly(4-vinylpyridine) films were obtained by the dip-coating method and thoroughly examined by X-ray reflectivity, transmission electron microscopy, atomic force microscopy, and grazing incidence small-angle scattering. Magnetic properties of the films were probed via superconducting quantum interference device (SQUID) magnetometry. It was demonstrated that due to the hydrogen bonding between P4VP and PAA, the Fe 3 O 4 @PAA NPs segregate selectively inside P4VP domains, enhancing the microphase separation process. This in turn, together with employing carefully optimized dip-coating parameters, results in the formation of hybrid thin films with highly ordered nanostructures. The addition of Fe 3 O 4 @PAA nanoparticles does not change the average interdomain spacing in the film lateral nanostructure. Moreover, it was shown that the nanoparticles can easily be removed to obtain well-ordered nanoporous templates.

The arrangement of two-dimensional graphene oxide sheets has been shown to influence physico-chemical properties of the final bulk structures. In particular, various graphene oxide microfibers remain of high interest in electronic applications due to their wire-like thin shapes and the ease of hydrothermal fabrication. In this research, we induced the internal ordering of graphene oxide flakes during typical hydrothermal fabrication via doping with Calcium ions (~6 wt.%) from the capillaries. The Ca 2+ ions allowed for better graphene oxide flake connections formation during the hydrogelation and further modified the magnetic and electric properties of structures compared to previously studied aerogels. Moreover, we observed the unique pseudo-porous fiber structure and flakes connections perpendicular to the long fiber axis. Pulsed electron paramagnetic resonance (EPR) and conductivity measurements confirmed the denser flake ordering compared to previously studied aerogels. These studies ultimately suggest that doping graphene oxide with Ca 2+ (or other) ions during hydrothermal methods could be used to better control the internal architecture and thus tune the properties of the formed structures.

Micro/nanostructures, which are assembled from various nanosized building blocks are of great scientific interests due to their combined features in the micro- and nanometer scale. This study for the first time demonstrates that ultrasmall superparamagnetic iron oxide nanoparticles can change the microstructure of their hydrocolloids under the action of external magnetic field. We aimed also at the establishment of the physiological temperature (39 °C) influence on the self-organization of silver and ultrasmall iron oxides nanoparticles (NPs) in hydrocolloids. Consequences of such induced changes were further investigated in terms of their potential effect on the biological activity in vitro. Physicochemical characterization included X-ray diffraction (XRD), optical microscopies (SEM, cryo-SEM, TEM, fluorescence), dynamic light scattering (DLS) techniques, energy dispersive (EDS), Fourier transform infrared (FTIR) and ultraviolet-visible (UV-Vis) spectroscopies, zeta-potential and magnetic measurements. The results showed that magnetic field affected the hydrocolloids microstructure uniformity, fluorescence properties and photodynamic activity. Likewise, increased temperature caused changes in NPs hydrodynamic size distribution and in hydrocolloids microstructure. Magnetic field significantly improved photodynamic activity that was attributed to enhanced generation of reactive oxygen species due to reorganization of the microstructure.

Reduced graphene oxide-magnetite hybrid aerogels attract great interest thanks to their potential applications, e.g., as magnetic actuators. However, the tendency of magnetite particles to migrate within the matrix and, ultimately, escape from the aerogel structure, remains a technological challenge. In this article we show that coating magnetite particles with polydopamine anchors them on graphene oxide defects, immobilizing the particles in the matrix and, at the same time, improving the aerogel structure. Polydopamine coating does not affect the magnetic properties of magnetite particles, making the fabricated materials promising for industrial applications.

Synthesis of magnetic nanoparticles and magnetic nanoclusters was performed by the co-precipitation method or solvothermal synthesis, respectively, followed by oxidative polymerization of dopamine, resulting in a polydopamine (PDA) shell. The nanomaterials obtained were described using TEM, FTIR and magnetic measurements. For the first time, cyto- and genotoxicity studies of polydopamine-coated nanostructures were performed on cancer and normal cell lines, providing in-depth insight into the toxicity of such materials. The tests conducted, e.g. ROS, apoptosis and DNA double-break of the nanomaterials obtained revealed the low toxicity of these structures. Thus, these results prove the biocompatibility and low genotoxicity of these materials and provide new data on the toxicity of PDA-coated materials, which is of great importance for their biomedical application., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Gd 2 (MoO 4 ) 3 (GMO) is a well-studied multiferroic material that exhibits full ferroelectric and ferroelastic behavior at room temperature. However, its difficult stabilization in thin films has prevented the study and exploitation of its multiferroic properties in different architectures. Here, we report on the study of GMO thin films deposited on Si(001) substrates by Pulsed Laser Deposition (PLD). The physicochemical properties of the films are discussed and studied. Results obtained by X-ray diffraction, X-ray photoelectron spectroscopy, high resolution transmission microscopy and second harmonic generation show that the orthorhombic (β'-GMO) multiferroic phase can be stabilized and homogenized by post deposition thermal reconstruction. Finally, the reconstruction process takes place via a complex surface mechanism with a clear leaf-like behavior.

Magnetite nanoparticles (NPs) decorated with silver (magnetite/Ag) are intensively investigated due to their application in the biomedical field. We demonstrate that the increase of silver content on the surface of nanoparticles improves the adsorptivity of antibiotic rifampicin as well as antibacterial properties. The use of ginger extract allowed to improve the silver nucleation on the magnetite surface that resulted in an increase of silver content. Physicochemical and functional characterization of magnetite/Ag NPs was performed. Our results show that 5%-10% of silver content in magnetite/Ag NPs is already sufficient for antimicrobial properties against Streptococcus salivarius and Staphylococcus aureus. The rifampicin molecules on the magnetite/Ag NPs surface made the spectrum of antimicrobial activity wider. Cytotoxicity evaluation of the magnetite/Ag/rifampicin NPs showed no harmful action towards normal human fibroblasts, whereas the effect on human embryonic kidney cell viability was time and dose dependent.