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In industrialized countries, health care associated infections, the fourth leading cause of disease, are a major health issue. At least half of all cases of nosocomial infections are associated with medical devices. Antibacterial coatings arise as an important approach to restrict the nosocomial infection rate without side effects and the development of antibiotic resistance. Beside nosocomial infections, clot formation affects cardiovascular medical devices and central venous catheters implants. In order to reduce and prevent such infection, we develop a plasma-assisted process for the deposition of nanostructured functional coatings on flat substrates and mini catheters. Silver nanoparticles (Ag NPs) are synthesized exploiting in-flight plasma-droplet reactions and are embedded in an organic coating deposited through hexamethyldisiloxane (HMDSO) plasma assisted polymerization. Coating stability upon liquid immersion and ethylene oxide (EtO) sterilization is assessed through chemical and morphological analysis carried out by means of Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). In the perspective of future clinical application, an in vitro analysis of anti-biofilm effect has been done. Moreover, we employed a murine model of catheter-associated infection which further highlighted the performance of Ag nanostructured films in counteract biofilm formation. The anti-clot performances coupled by haemo- and cytocompatibility assays have also been performed. [ABSTRACT FROM AUTHOR]

Turning thermosets into fully sustainable materials requires utilization of biobased raw materials and design for easy recyclability. Here, dynamic covalent chemistry for fabrication of covalent adaptable networks (CANs) could be an enabling tool. CAN thermosets ideally combine the positive material properties of thermosets with thermal recyclability of linear thermoplastics. Among the dynamic covalent bonds, imine bond, also called Schiff base, can participate in both dissociative and associative pathways. This induces potential for chemical recyclability, thermal reprocessability and self‐healing. This review presents an overview of the current research front of biobased thermosets fabricated by Schiff base chemistry. The discussed materials are categorized on the basis of the employed biobased components. The chemical approaches for the synthesis and curing of the resins, as well as the resulting properties and recyclability of the obtained thermosets are described and discussed. Finally, challenges and future perspectives are briefly summarized. [ABSTRACT FROM AUTHOR]

Partnered operations are very frequent and pose complex questions in international law, such as the allocation of responsibility in cases of violations of international human rights law and/or international humanitarian law (IHL). The present article deals with the question of complicity in partnered operations between States and between States and/or non-State actors, focusing on the possible overlap between responsibility for complicity and responsibility for breach of positive obligations in partnered operations in the light of the relevant case law of the International Court of Justice and of the European Court of Human Rights. As the requirements laid down by art. 16 of the International Law Commission Draft Articles on the Responsibility of States with respect to complicity are often difficult to meet, the author intends to explore the potential advantages of resorting to positive obligations in light of the due diligence standard. Although the article focuses primarily on human rights violations, in the final section the author investigates the benefits of this approach also with respect to breaches of IHL. [ABSTRACT FROM AUTHOR]

In the clinical management of solid tumors, the possibility to successfully couple the regeneration of injured tissues with the elimination of residual tumor cells left after surgery could open doors to new therapeutic strategies. In this work, we present a composite hydrogel–electrospun nanofiber scaffold, showing a modular architecture for the delivery of two pharmaceutics with distinct release profiles, that is potentially suitable for local therapy and post-surgical treatment of solid soft tumors. The composite was obtained by coupling gelatin hydrogels to poly(ethylene oxide)/poly(butylene terephthalate) block copolymer nanofibers. Results of the scaffolds' characterization, together with the analysis of gelatin and drug release kinetics, displayed the possibility to modulate the device architecture to control the release kinetics of the drugs, also providing evidence of their activity. In vitro analyses were also performed using a human epithelioid sarcoma cell line. Furthermore, publicly available expression datasets were interrogated. Confocal imaging showcased the nontoxicity of these devices in vitro. ELISA assays confirmed a modulation of IL-10 inflammation-related cytokine supporting the role of this device in tissue repair. In silico analysis confirmed the role of IL-10 in solid tumors including 262 patients affected by sarcoma as a negative prognostic marker for overall survival. In conclusion, the developed modular composite device may provide a key-enabling technology for the treatment of soft tissue sarcoma. [ABSTRACT FROM AUTHOR]

The recent burst of research on smart materials is a clear evidence of the growing interest of the scientific community, industry, and society in the field. The exploitation of the great potential of stimuli‐responsive materials for sensing, actuation, logic, and control applications is favored and supported by new manufacturing technologies, such as electrospinning, that allows to endow smart materials with micro‐ and nanostructuration, thus opening up additional and unprecedented prospects. In this wide and lively scenario, this article systematically reviews the current advances in the development of thermoactive electrospun fibers and textiles, sorting them, according to their response to the thermal stimulus. Hence, several platforms including thermoresponsive systems, shape memory polymers, thermo‐optically responsive systems, phase change materials, thermoelectric materials, and pyroelectric materials, are described and critically discussed. The difference in active species and outputs of the aforementioned categories is highlighted, evidencing the transversal nature of temperature stimulus. Moreover, the potential of novel thermoactive materials are pointed out, revealing how their development could take to utmost interesting achievements. [ABSTRACT FROM AUTHOR]

In recent years, the main quest of science has been the pioneering of the groundbreaking biomedical strategies needed for achieving a personalized medicine. Ribonucleic acids (RNAs) are outstanding bioactive macromolecules identified as pivotal actors in regulating a wide range of biochemical pathways. The ability to intimately control the cell fate and tissue activities makes RNA‐based drugs the most fascinating family of bioactive agents. However, achieving a widespread application of RNA therapeutics in humans is still a challenging feat, due to both the instability of naked RNA and the presence of biological barriers aimed at hindering the entrance of RNA into cells. Recently, material scientists' enormous efforts have led to the development of various classes of nanostructured carriers customized to overcome these limitations. This work systematically reviews the current advances in developing the next generation of drugs based on nanotechnology‐assisted RNA delivery. The features of the most used RNA molecules are presented, together with the development strategies and properties of nanostructured vehicles. Also provided is an in‐depth overview of various therapeutic applications of the presented systems, including coronavirus disease vaccines and the newest trends in the field. Lastly, emerging challenges and future perspectives for nanotechnology‐mediated RNA therapies are discussed. [ABSTRACT FROM AUTHOR]

Uncontrolled oxidative stress production, especially in the outer retina is one of the causes of retinal degenerations. Mitochondria are considered the principal source of oxidative stress. However, a Reactive Oxygen Intermediates (ROI) production in the retinal photoreceptor layer seems to depend also on the expression of an extramitochondrial oxidative phosphorylation (OxPhos) machinery in the rod outer segments (OS). In fact, OS conduct aerobic metabolism, producing ATP through oxygen consumption, although it is devoid of mitochondria. As diterpenes display an antioxidant effect, we have evaluated the effect Manool, extracted from Salvia tingitana, on the extramitochondrial OxPhos and the ROI production in the retinal rod OS. Results confirm that the OxPhos machinery is ectopically expressed in the OS and that F1Fo‐ATP synthase is a target of Manool, which inhibited the OS ATP synthesis, binding the F1 moiety with high affinity, as analysed by molecular docking. Moreover, the overall slowdown of OxPhos metabolism reduced the ROI production elicited in the OS by light exposure, in vitro. In conclusion, data are consistent with the antioxidant properties of Salvia spp., suggesting its ability to lower oxidative stress production, a primary risk factor for degenerative retinal diseases. Significance of the study: Here we show that Manool, a diterpene extracted from Salvia tingitana has the potential to lower the free radical production by light‐exposed rod outer segments in vitro, by specifically targeting the rod OS F1Fo‐ATP synthase belonging to the extramitochondrial OxPhos expressed on the disk membrane. The chosen experimental model allowed to show that the rod OS is a primary producer of oxidative stress linked to the pathogenesis of degenerative retinal diseases. Data are also consistent with the antioxidant and anti‐inflammatory action of Salvia spp., suggesting a beneficial effect also in vivo. [ABSTRACT FROM AUTHOR]

The terpene‐based monomers and polymers reported in the literature are mostly hydrophobic and this is limiting their use in aqueous environments. To address this drawback, we have developed a novel synthetic strategy to functionalise a model terpene monomer in order to improve hydrophilicity and the number of polar groups on the polymer side chains. To produce a highly hydrophilic monomer, carvone (meth)acrylate was chosen as the primary feedstock. Carvone has more functionalisable double bonds than other commercial cyclic terpenes and offers the potential for the maximum number of hydrophilic groups per monomer molecule. The monomers were homopolymerised and copolymerised to generate novel green hydrophilic and amphiphilic terpene‐based polymers which were characterised by 1H–13C NMR, gel permeation chromatography, TGA and DSC analyses. © 2020 Society of Industrial Chemistry [ABSTRACT FROM AUTHOR]

The influence of the liquid composition on the chemical and morphological properties of copper-based nanostructures synthesized by a non-equilibrium atmospheric plasma treatment is investigated and discussed. The synthesis approach is simple and environmentally friendly, employs a non-equilibrium nanopulsed atmospheric pressure plasma jet as a contactless cathode and a Cu foil as immersed anode. The process was studied using four distinct electrolyte solutions composed of distilled water and either NaCl + NaOH, NaCl only or NaOH only at two different concentrations, without the addition of any copper salts. CuO crystalline structures with limited impurities (e.g. Cu and Cu(OH)2 phases) were produced from NaCl + NaOH containing solutions, mainly CuO and CuCl2 structures were synthesized in the electrolyte solution containing only NaCl and no synthesis occurred in solutions containing only NaOH. Both aggregated and dispersed nanostructures were produced in the NaCl + NaOH and NaCl containing solutions. Reaction pathways leading to the formation of the nanostructures are proposed and discussed. [ABSTRACT FROM AUTHOR]

CuO is a versatile p-type material for energy applications capable of imparting diverse functionalities by manipulating its band-energy diagram. We present ultra-small quantum confined cupric oxide nanoparticles (CuO NPs) synthesized via a simple one-step environmentally friendly atmospheric pressure microplasma synthesis process. The proposed method, based on the use of a hybrid plasma-liquid cell, enables the synthesis of CuO NPs directly from solid metal copper in ethanol with neither surfactants nor reducing agents. CuO NPs films are then used for the first time in all-inorganic third generation solar cell devices demonstrating highly effective functionalities as blocking layer. [ABSTRACT FROM AUTHOR]

A single step process for the deposition of nanocomposite coatings with silver nanoparticles (AgNPs) embedded in a plasma-polymerized polyacrylic acid (pPAA) matrix and performed using a non-equilibrium atmospheric pressure plasma jet is presented. Acrylic acid (AA) and AgNPs dispersed in ethanol (EtOH) are used as precursors and are separately injected in the plasma region directly; Ar is used as plasma gas and also as carrier gas for both precursors. Scanning electron microscopy (SEM) and ATR-FTIR analysis show the deposition of a micrometric pPAA coating on the polyethylene (PE) film used as substrate; AgNPs embedded in the polymeric matrix are visible in SEM pictures and their presence is confirmed by XPS and EDS analysis. X-ray photoelectron spectroscopy (XPS) also highlights a high retention of carboxylic groups in the pPAA chemical structure and the surface oxidation of AgNPs. Preliminary results of the antibacterial activity of the co-deposited coatings are presented. [ABSTRACT FROM AUTHOR]

Successful plasma-polymerization of acrylic acid (AA), aimed at depositing plasma-polymerized polyacrylic acid (pPAA) coatings stable upon water contact with a high amount of carboxyl groups, using a non-equilibrium atmospheric pressure nanopulsed plasma jet is reported. Special attention is devoted to the surface chemical characterization of the pPAA coatings deposited on pristine and plasma pretreated polymeric substrates. The investigation of the pPAA chemical structure is performed by means of attenuated total reflectance-Fourier transform infrared and X-ray photoelectron spectroscopies. Insights on the morphological characteristics of the coatings are also provided by optical microscopy. [ABSTRACT FROM AUTHOR]

The idea of establishing centres for the "external processing" of asylum claims -- already supported by some European Union (EU) Member States, and actually realized in the Caribbean by the United States and in the Pacific area by Australia -- has recently come to the fore again in European debates. The recent proposals -- which tend to create offshore centres in Turkey and probably in African countries too -- envisage various levels of involvement of EU Member States and of the EU itself. The present contribution aims to analyse, in particular, which of the various actors implicated would be responsible, and to what extent, in cases of violation of asylum seekers' human rights. The scenario that could be envisaged is extremely complex. Disentangling the web of action/attribution/responsibility is very difficult and the risk of "blame shifting" or "passing the buck" among the various actors is high. The possibility of the extraterritorial application of the European Convention on Human Rights will also be explored, in order to assess to what extent individuals would have access to a remedy before the European Court of Human Rights. [ABSTRACT FROM AUTHOR]

Atmospheric non-equilibrium plasma is drawing interest as a promising tool for cancer treatment due to its blend of physical and chemical components that can exert anti-tumor effects. In this work, we investigate the effects of plasma treatment, performed by means of a wand electrode DBD driven by nanosecond high voltage pulses, on the viability, proliferation, and cell-cycle distribution of cells of mouse lymphoma. Results for direct treatment, with cell exposed to plasma while suspended in culture medium, and indirect treatment, where cells were added to culture medium previously activated by plasma treatment, are compared. A qualitative characterization by means of high-speed and iCCD imaging of the plasma discharges produced for the different operating conditions adopted in biological experiments, as well as a semi-quantitative study of the reactive species produced by plasma treatment in the culture medium, are also presented. [ABSTRACT FROM AUTHOR]

In this work, the effectiveness of atmospheric pressure non-equilibrium plasma, generated by a dielectric barrier discharge and operated in air, in successfully crosslinking water soluble pullulan electrospun fibers is demonstrated. After being exposed to plasma, the fibers show a remarkable capability to preserve structural stability and fiber morphology upon water exposure. The gel fraction and the water absorption are quantified to evaluate the crosslinking efficiency of different plasma operating conditions, and ATR-FTIR characterization provided some insights into plasma-induced modification of pullulan chemical structure. [ABSTRACT FROM AUTHOR]

Low power atmospheric pressure inductively coupled thermal plasma sources integrated with a quenching device (cold ICP) for the efficient production of biologically active agents have been recently developed for potential biomedical applications. In the present work, in vitro experiments aimed at assessing the decontamination potential of a cold ICP source were carried out on bacteria typically associated with chronic wounds and designed to represent a realistic wound environment; further in vitro experiments were performed to investigate the effects of plasma-irradiated physiological saline solution on eukaryotic cells viability. A thorough characterization of the plasma source and process, for what concerns ultraviolet (UV) radiation and nitric oxide production as well as the variation of pH and the generation of nitrates and nitrites in the treated liquid media, was carried out to garner fundamental insights that could help the interpretation of biological experiments. Direct plasma treatment of bacterial cells, performed at safe level of UV radiation, induces a relevant decontamination, both on agar plate and in physiological saline solution, after just 2 min of treatment. Furthermore, the indirect treatment of eukaryotic cells, carried out by covering them with physiological saline solution irradiated by plasma, in the same conditions selected for the direct treatment of bacterial cells does not show any noticeable adverse effect to their viability. Some considerations regarding the role of the UV radiation on the decontamination potential of bacterial cells and the viability of the eukaryotic ones will be presented. Moreover, the effects of pH variation, nitrate and nitrite concentrations of the plasma-irradiated physiological saline solution on the decontamination of bacterial suspension and on the viability of eukaryotic cells subjected to the indirect treatment will be discussed. The obtained results will be used to optimize the design of the ICP source for an effective production of reactive species, while keeping effluent temperature and UV radiation at values compatible with biomedical treatments. [ABSTRACT FROM AUTHOR]

The structure, fluid-dynamic behavior, temperature, and radiation emission of a cold atmospheric pressure plasma jet driven by high-voltage pulses with rise time and duration of a few nanoseconds have been investigated. Intensified charge-coupled device (iCCD) imaging revealed that the discharge starts when voltage values of 5–10 kV are reached on the rising front of the applied voltage pulse; the discharge then propagates downstream the source outlet with a velocity around 10^7 – 10^8 cm/s. Light emission was observed to increase and decrease periodically and repetitively during discharge propagation. The structure of the plasma plume presents a single front or either several branched subfronts, depending on the operating conditions; merging results of investigations by means of Schlieren and iCCD imaging suggests that branching of the discharge front occurs in spatial regions where the flow is turbulent. By means of optical emission spectroscopy, discharge emission was observed in the ultraviolet-visible (UV-VIS) spectral range (N2, N2+, OH, and NO emission bands); total UV irradiance was lower than 1 $\mu $ W/ \mathrm{cm}^{2} even at short distances from the device outlet (<15 mm). Plasma plume temperature does not exceed 45 °C for all the tested operating conditions and values close to ambient temperature were measured around 10 mm downstream the source outlet. [ABSTRACT FROM PUBLISHER]

This research has been conducted inside the theoretical framework of Social Representations. By interviewing Italian and Rumanian subjects belonging different social groups we examined how "expert" and "lay" people face the unfamiliar phenomenon of the economic crisis. Starting from the SR's Structural Approach, data were collected through a multi-method strategy. Four groups of participants (N=120 for each country; group/gender balanced) were employed: university students, mid-level bank clerks, shopkeepers, and laypeople. Data were treated with rang/frequency, similitude analysis and mono/multivariate statistical analysis. Discussion focuses on the relationships between culture, group affiliation, SRs of crisis and economic behaviors. The main findings reveal culture and group affiliation differences in the ways participants define and foresee strategies to face the crisis. In both Italian and Romanian samples, differences were founded among expert and lay groups. Italian and Romanian SRs, differ with reference to the meaning of the salient elements and their organization. [ABSTRACT FROM AUTHOR]

In this study, atmospheric pressure non-thermal plasma treatment of electrospun poly( L-lactic acid) scaffolds is used to improve scaffold hydrophilicity and to introduce carboxyl groups on scaffold surface. Thermo-mechanical properties, morphology, hydrophilicity, and water uptake of the plasma-treated scaffolds are studied. The amount of carboxyl functional groups on the scaffold surface is evaluated using fluorescein isothiocyanate conjugation and microdensitometry. The effect of plasma treatment on mouse embryonic fibroblast morphology is assessed through image analysis. Results show an enhancement of scaffold biocompatibility, demonstrating that atmospheric plasma technology is a flexible process that can be integrated in 'in-line' procedures of biomaterial fabrication and functionalization. [ABSTRACT FROM AUTHOR]

In the field of artificial prostheses for damaged vessel replacement, polymeric scaffolds showing the right combination of mechanical performance, biocompatibility, and biodegradability are still demanded. In the present work, poly(butylene-co-triethylene trans-1,4-cyclohexanedicarboxylate), a biodegradable random aliphatic copolyester, has been synthesized and electrospun in form of aligned and random fibers properly designed for vascular applications. The obtained materials were analyzed through tensile and dynamic-mechanical tests, the latter performed under conditions simulating the mechanical contraction of vascular tissue. Furthermore, the in vitro biological characterization, in terms of hemocompatibility and cytocompatibility in static and dynamic conditions, was also carried out. The mechanical properties of the investigated scaffolds fit within the range of physiological properties for medium- and small-caliber blood vessels, and the aligned scaffolds displayed a strain-stiffening behavior typical of the blood vessels. Furthermore, all the produced scaffolds showed constant storage and loss moduli in the investigated timeframe (24 h), demonstrating the stability of the scaffolds under the applied conditions of mechanical deformation. The biological characterization highlighted that the mats showed high hemocompatibility and low probability of thrombus formation; finally, the cytocompatibility tests demonstrated that cyclic stretch of electrospun fibers increased endothelial cell activity and proliferation, in particular on aligned scaffolds. [ABSTRACT FROM AUTHOR]

The "pulsed electron deposition" (PED) technique, in which a solid target material is ablated by a fast, high-energy electron beam, was initially developed two decades ago for the deposition of thin films of metal oxides for photovoltaics, spintronics, memories, and superconductivity, and dielectric polymer layers. Recently, PED has been proposed for use in the biomedical field for the fabrication of hard and soft coatings. The first biomedical application was the deposition of low wear zirconium oxide coatings on the bearing components in total joint replacement. Since then, several works have reported the manufacturing and characterization of coatings of hydroxyapatite, calcium phosphate substituted (CaP), biogenic CaP, bioglass, and antibacterial coatings on both hard (metallic or ceramic) and soft (plastic or elastomeric) substrates. Due to the growing interest in PED, the current maturity of the technology and the low cost compared to other commonly used physical vapor deposition techniques, the purpose of this work was to review the principles of operation, the main applications, and the future perspectives of PED technology in medicine. [ABSTRACT FROM AUTHOR]

The majority of the crosslinking approaches employed to confer water resistance properties to electrospun gelatin mats are based on the use of potential cytotoxic agents, turning out to be not suitable for biomedical applications. Environmentally friendly chemical strategies based on the use of non-toxic agents are, therefore, strongly demanded. In the present work, the possibility to produce crosslinked electrospun fish gelatin mats by electrospinning an aqueous solution, containing citric acid as a crosslinking agent, is reported. The effect of pH on solution rheological properties, as well as on the electrospun mat morphology, chemistry, and crosslinking degree, is assessed. The increase of solution pH from 1.8 to 3.7 allows for obtaining fibers that maintain the fibrous morphology also in the mat. Subsequent thermal treatment of the electrospun mat (80 °C for 30 min) turns out to increase the crosslinking degree and morphological stability of the mat. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharges (DBDs) are being studied for a wide range of biomedical and industrial applications. In this paper, qualitative results coming from synchronized high-speed and Schlieren multi-imaging of a unipolar nanosecond-pulsed DBD are presented, with the final aim of showing plasma structure, filament movement, and refractive index gradients in different interelectrode gaps and counter electrode materials. [ABSTRACT FROM PUBLISHER]

Intense and energetic atmospheric plasma was achieved by jet-to-jet coupling using an array of plasma jets arranged in an axisymmetric structure. To highlight the effects of pulse repetition frequency, peak voltage and mass flow rate on the transition from a coupled mode to an uncoupled one, qualitative results coming from iCCD imaging of a nanopulsed Gatling machine gun-like plasma source will be shown. Moreover, results on surface modifications and bacterial inactivation will be presented. [ABSTRACT FROM PUBLISHER]

High-speed and Schlieren imaging have been used to visualize ignition transients, discharge behavior and flow fields of a plasma device integrating a low-power inductively coupled plasma torch, generating a high temperature thermal plasma, with a quenching device, able to cool the gaseous effluent down to biocompatible temperatures for effective use in biomedical applications. [ABSTRACT FROM PUBLISHER]

Electrospun gelatin nanofibers attract great interest as a natural biomaterial for cartilage and tendon repair despite their high solubility in aqueous solution, which makes them also difficult to crosslink by means of chemical agents. In this work, we explore the efficiency of non-equilibrium atmospheric pressure plasma in stabilizing gelatin nanofibers. We demonstrate that plasma represents an innovative, easy and environmentally friendly approach to successfully crosslink gelatin electrospun mats directly in the solid state. Plasma treated gelatin mats display increased structural stability and excellent retention of fibrous morphology after immersion in aqueous solution. This method can be successfully applied to induce crosslinking both in pure gelatin and genipin-containing gelatin electrospun nanofibers, the latter requiring an even shorter plasma exposure time. A complete characterization of the crosslinked nanofibres, including mechanical properties, morphological observations, stability in physiological solution and structural modifications, has been carried out in order to get insights on the occurring reactions triggered by plasma. [ABSTRACT FROM AUTHOR]

Front Cover: Non‐thermal atmospheric pressure plasma allowed surface properties modification of electrospun poly(L‐lactic acid) scaffold. Mouse embryonic fibroblast cells cultured on treated scaffolds showed a more elongated and “dendritic” morphology than cells cultured on the untreated ones. Further details can be found in the article by Maria Letizia Focarete et. al. on page 203. [ABSTRACT FROM AUTHOR]