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Ship weather routing, which involves suggesting low-emission routes, holds potential for contributing to the decarbonisation of maritime transport. However, including because of a lack of readily deployable open-source and open-language computational models, its quantitative impact has been explored only to a limited extent. As a response, the graph-search VISIR (discoVerIng Safe and effIcient Routes) model has been refactored in Python, incorporating novel features. For motor vessels, the angle of attack of waves has been considered, while for sailboats the combined effects of wind and sea currents are now accounted for. The velocity composition with currents has been refined, now encompassing leeway as well. Provided that the performance curve is available, no restrictions are imposed on the vessel type. A cartographic projection has been introduced. The graph edges are quickly screened for coast intersection via a K-dimensional tree. A least-CO2 algorithm in the presence of dynamic graph edge weights has been implemented and validated, proving a quasi-linear computational performance. The software suite's modularity has been significantly improved, alongside a thorough validation against various benchmarks. For the visualisation of the dynamic environmental fields along the route, isochrone-bounded sectors have been introduced. The resulting VISIR-2 model has been employed in numerical experiments within the Mediterranean Sea for the entirety of 2022, utilising meteo-oceanographic analysis fields. For a 125 m long ferry, the percentage saving of overall CO2 expenditure follows a bi-exponential distribution. Routes with a carbon dioxide saving of at least 2 % with respect to the least-distance route were found for prevailing beam or head seas. Two-digit savings, up to 49 %, were possible for about 10 d in a year. In the case of an 11 m sailboat, time savings increased with the extent of path elongation, particularly during upwind sailing. The sailboat's routes were made approximately 2.4 % faster due to optimisation, with the potential for an additional 0.8 % in savings by factoring in currents. VISIR-2 serves as an integrative model, uniting expertise from meteorology, oceanography, ocean engineering, and computer science, to evaluate the influence of ship routing on decarbonisation efforts within the shipping industry.

Abstract Introduction Survival from refractory out of hospital cardiac arrest (OHCA) without timely return of spontaneous circulation (ROSC) utilising conventional advanced cardiac life support (ACLS) therapies is dismal. CHEER3 was a safety and feasibility study of pre-hospital deployed extracorporeal membrane oxygenation (ECMO) during cardiopulmonary resuscitation (ECPR) for refractory OHCA in metropolitan Australia. Methods This was a single jurisdiction, single-arm feasibility study. Physicians, with pre-existing ECMO expertise, responded to witnessed OHCA, age

The integration of distributed energy resources (DERs) in electric distribution networks originates the Active Distribution Networks (ADNs). The presence of DERs introduces challenges to conventional protection schemes due to bidirectional power flows and variations in fault current magnitudes; furthermore, the connection and disconnection of DERs result in multiple ADN operating modes (OMs), deteriorating the effective operation of protective relays. Considering the above, this document presents an adaptive protection strategy to address the challenges related to the variable nature of the ADN operation. The main contribution of the proposed approach is accurate islanded mode detection without requiring communication links, enabling fault detection in all ADN operating modes. The protection strategy maintains directional overcurrent relays' coordination using local voltage and current measurements to continuously estimate the Thevenin equivalent, fault currents, and adaptive coefficients.Relay coordination is maintained through tests conducted on a modified IEEE 34-bus feeder, considering several OMs, fault types, and locations. A comparison between the proposed adaptive protection strategy and a conventional overcurrent scheme shows that relay operating time is better in 100% of the analysed cases for the former strategy. On the other hand, the maximum errors in the fault current estimation using the Thevenin equivalent parameters are between 0.05% to 2.6% for all of the analysed operating modes when compared with the true fault current magnitudes. Finally, the adequate results validate the potential of the proposed communication-less protection strategy for modern protective relaying applications.

Abstract The clinical course of COVID-19 may show severe presentation, potentially involving dynamic cytokine storms and T cell lymphopenia, which are leading causes of death in patients with SARS-CoV-2 infection. Plasma exchange therapy (PLEX) effectively removes pro-inflammatory factors, modulating and restoring innate and adaptive immune responses. This clinical trial aimed to evaluate the impact of PLEX on the survival of patients with severe SARS-CoV-2 and the effect on the cytokine release syndrome. Hospitalized patients diagnosed with SARS-CoV-2 infection and cytokine storm syndrome were selected to receive 2 sessions of PLEX or standard therapy. Primary outcome was all-cause 60-days mortality; secondary outcome was requirement of mechanical ventilation, SOFA, NEWs-2 scores modification, reduction of pro-inflammatory biomarkers and hospitalization time. Twenty patients received PLEX were compared against 40 patients receiving standard therapy. PLEX reduced 60-days mortality (50% vs 20%; OR 0.25, 95%CI 0.071–0.880; p = 0.029), and this effect was independent from demographic variables and drug therapies used. PLEX significantly decreased SOFA, NEWs-2, pro-inflammatory mediators and increased lymphocyte count, accompanied with a trend to reduce affected lung volume, without effect on SatO2/FiO2 indicator or mechanical ventilation requirement. PLEX therapy provided significant benefits of pro-inflammatory clearance and reduction of 60-days mortality in selected patients with COVID-19, without significant adverse events.

This research examined the problems experienced by women who work in the informal sector of the city of Riobamba due to receiving poor and lower incomes than men. The main objective was to analyze the influence that gender has on wages of women in this sector, to establish strategies that can promote more equitable development. Qualitative and quantitative approaches were used using inductive and deductive methods. Data were collected through a survey and analyzed using the Chi square test. The results showed that women's wages were dependent on their gender, conditioned by a sociocultural environment that has not evolved, especially in the informal sectors made up mostly of rural population. Also, the presence of child labor was evident, and wages could not cover the basic needs of women who identified as heads of household with family responsibilities of between three to five people. The strategy identified to promote equity in the recognition and value of fair work without distinction of gender was based on the following elements: the implementation of inclusion policies and control, training of young women in non-traditional trades, promotion of changes in traditional patterns in households, and policies to combat poverty with a gender focus for sustainable social development. Keywords: gender, equity, salary, strategies, socioeconomic, management. Resumen La investigación plantea la problemática que viven las mujeres que trabajan en el sector informal de la ciudad de Riobamba debido a su condición de género para percibir ingresos deficientes e inferiores a los hombres, el objetivo principal es analizar la incidencia que tiene el género en el salario de las mujeres de este sector para el establecimiento de estrategias que promuevan un desarrollo más equitativo. La metodología investigativa considera estudios analíticos, correlacionales, exploratorios, de campo, un enfoque cuali- cuantitativo, con métodos inductivos y deductivos, usando técnicas como la encuesta, considerado la relación de dependencia a través del Chi cuadrado para la comprobación de la hipótesis, como resultados principales se puede encontrar que la incidencia del género en los salarios de las mujeres es dependiente, condicionado por un ambiente sociocultural que no ha evolucionado sobre todo en los sectores informales conformados en su mayoría por población rural, se evidencia la presencia del trabajo infantil y salarios que no pueden cubrir las necesidades básicas de mujeres que se identifican como jefes de hogar con cargas familiares de entre 3 a 5 personas, se plantea como solución la estrategia para promover la equidad en el reconocimiento y puesta en valor del trabajo equitativo sin distinción de género basada en 5 elementos: la implementación de políticas de inclusión y control, la capacitación de las jóvenes en oficios no tradicionales, promoción de cambios de patrones tradicionales en los hogares, políticas de combate a la pobreza con enfoque de género para un desarrollo social sustentable. Palabras clave: género, equidad, salario, estrategias, socioeconómicas, gestión.

Yellow-bellied slider turtles (Trachemys scripta scripta) are increasingly being used as animal models for experimental purposes. The aim of this work was to generate some seasonal haematological information for captive yellow-bellied slider turtles as a useful and complementary tool for research trials. Blood samples from 30 healthy adult yellow-bellied turtles (13 males and 17 females) were obtained in winter and summer, and complete blood counts were performed. Within each season, the medians for males and females were compared using the Wilcoxon test for independent data. Likewise, the medians for both seasons were compared by means of the Wilcoxon test for paired data. All P-values were corrected using the Bonferroni multiple comparisons procedure. The concordance of the two methods used to determine the thrombocyte count (haemocytometer and smear estimation) was evaluated using intraclass correlation coefficients. The effects of sex were not statistically significant in either season (Bonferroni correction). However, values of heterophils, lymphocytes, basophils, and thrombocytes (haemocytometer method), when compared between seasons, exhibited differences that remained statistically significant after Bonferroni correction. Whereas heterophils were the most numerous leukocytes in summer for both sexes, basophils were the most numerous leukocytes in winter. In addition, lymphocyte percentages were also higher in winter for both sexes. Smear thrombocyte estimations did not show any significant differences between sexes and between seasons. However, when using the haemocytometer method, summer values were significantly higher than winter ones. The concordance between the two methods for measuring the thrombocyte count was not statistically significant in winter, but there was significant concordance in summer. Although the two techniques can be complementary, we recommend smear estimation as an easier and more reliable method. The haematological values obtained in this study may be useful as a complementary profile for researchers carrying out experimental procedures with this turtle subspecies.

Biodegradable poly(lactic-co-glycolic acid) copolymer, PLGA nanoparticles (NPs) with a surface layer of poly (ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymers, Pluronics, are promising drug carrier systems. With the aim to increase the potential of targeted drug delivery the end group derivative of Pluronics was synthesized in a straightforward way to obtain Pluronic-amines. The formation of functional amine groups was confirmed by fluorescamine method and NMR analysis of their N-(tert-Butoxycarbonyl)-L-phenylalanine (Boc-Phe-OH) and N-(9-Fluorenylmethoxycarbonyl)-L-phenylalanine (Fmoc-Phe-OH) conjugates. Pluronic and Pluronic-amine stabilized PLGA NPs prepared by nanoprecipitation were characterized by dynamic light scattering and zeta potential measurements. All of the systems showed high colloidal stability checked by electrolyte induced aggregation, although the presence of Pluronicamine on the surface decreased the zeta potential in some extent. The introduction of reactive primary amine groups into the surface layer of PLGA NPs while preserving the aggregation stability, provides a possibility for coupling of various ligands allowing targeted delivery and also contributes to the improved membrane affinity of NPs.

Disposición final de las rapaces admitidas en el Centro de Rehabilitación de Fauna Silvestre de Tafira, Gran Canaria, España (2003–2013) En este estudio se analizan los resultados de la rehabilitación de aves rapaces silvestres admitidas en el Centro de Rehabilitación de Fauna Silvestre de Tafira en la isla de Gran Canaria, España, desde 2003 hasta 2013, mediante un sistema de auditoría de la calidad basado en los índices generales y clasificados (por causa de admisión) de las cuatro categorías de disposición final, el tiempo hasta la muerte y el tiempo de permanencia como indicadores de calidad. Las categorías de disposición final fueron: eutanasia (Er) = 19,78%, mortalidad no asistida durante la hospitalización (Mr) = 22,20%, liberación (Rr) = 57,57% y cautividad permanente (Cr) = 0,46%. Teniendo en cuenta la especial vulnerabilidad de las especies de rapaces insulares y el alto índice de Rr conseguido, los resultados de este estudio ponen de relieve la importancia de los centros de rehabilitación de fauna silvestre en el tratamiento médico de las aves heridas y la consiguiente liberación de las aves rehabilitadas.

Chiari malformation type I (CM-I) is a rare condition with physical and neurological manifestation changing across people. Being a chronic and debilitating disease, a comprehensive multidisciplinary approach is needed for evaluating patient’s experienced Quality of Life (QoL) and psychological correlates of CM. Objectives: The aim of this study was to develop the Italian adaptation of Chiari Symptom Profile (CSP), a questionnaire assessing the core symptoms of Chiari malformation and their impact on people’s lives. Secondly, the occurrence of anxiety/depression symptoms and associations with patient-reported QoL were explored. Methods: 172 adults with diagnosed CM-I (N=79 with neurosurgery) completed an online questionnaire measuring general QoL (WHOQOL-brief), disease-related QoL (CSP), and symptoms of anxiety/depression (HADS). Participant’s demographic and clinical data were also collected. Results: The Italian version of CSP showed excellent reliability both in total (Cronbach alpha = .97) and factorial scores (alphas from .87 to .95) assessing four domains of Chiari-related QoL (functional, physical, social, and psychological). For construct validity, significant correlations (p .001) resulted among severity of CM symptoms, social and daily limitations assessed by CSP and general QoL. Participants’ age at neurosurgery and condition (with/without neurosurgery treatment) did not significantly impact QoL scores, but perceived QoL worsened with increasing age. Among participants, 32% reported clinical anxiety and 14% depression symptoms (with higher incidence of depression in non-operated participants). Participants with clinical anxiety/depression reported a worse QoL in all domains of CSP (functional, physical, social, and psychological). Conclusion: Findings suggest the need to include in CM treatment a continuous psychological support, identifying the patients most at risk who, in time, they may experience greater psychological suffering.

Thermal analysis is widely employed for the characterization of nanomaterials. It encompasses a variety of techniques that allow the evaluation of the physicochemical properties of a material by monitoring its response under controlled temperature. In the case of carbon nanomaterials, such as carbon nanotubes and graphene derivatives, thermogravimetric analysis (TGA) is particularly useful to determine the quality and stability of the sample, the presence of impurities and the degree of functionalization or doping after post-synthesis treatments. Furthermore, TGA is widely used to evaluate the thermal stability against oxidation by air, which can be, for instance, enhanced by the purification of the material and by nitrogen doping, finding application in areas where a retarded combustion of the material is required. Herein, we have evaluated key parameters that play a role in the data obtained from TGA, namely, gas flow rate, sample weight and temperature rate, used during the analysis. We found out that the heating rate played the major role in the process of combustion in the presence of air, inducing an increase in the temperature at which the oxidation of CNTs starts to occur, up to ca. 100 °C (from 1 °C min -1 to 50 °C min -1 ). The same trend was observed for all the evaluated systems, namely N-doped CNTs, graphene produced by mechanical exfoliation and N-doped reduced graphene samples. Other aspects, like the presence of impurities or structural defects in the evaluated samples, were analyzed by TGA, highlighting the versatility and usefulness of the technique to provide information of structural aspects and properties of carbon materials. Finally, a set of TGA parameters are recommended for the analysis of carbon nanomaterials to obtain reliable data.

The new compounds R 2 TaO 4- x N x with R = La, Ce, Nd, and Eu and 1.20 ≤ x ≤ 2.81 have been obtained by a solid-state reaction between metal nitrides and oxides or oxynitrides under N 2 gas at temperatures between 1200 and 1700 °C. They are the first examples of rare earth transition metal oxynitrides with an n = 1 Ruddlesden-Popper structure and show different anion stoichiometries, crystal structures, and magnetic properties. Synchrotron X-ray powder diffraction and electron diffraction indicate that the lanthanum, cerium, and neodymium compounds crystallize in the orthorhombic space group Pccn , with cell parameters a = 5.72949(2), b = 5.73055(5), and c = 12.77917(6) Å for La 2 TaO 1.31 N 2.69 , a = 5.70500(5), b = 5.71182(4), and c = 12.61280(7) Å for Ce 2 TaO 1.19 N 2.81 , and a = 5.70466(3), b = 5.70476(5), and c = 12.32365(5) Å for Nd 2 TaO 1.46 N 2.54 . In contrast, Eu 2 TaO 2.80 N 1.20 shows a tetragonal I 4 1 / acd superstructure doubling the c axis, with parameters a = 5.71867(2) and c = 25.00092(19) Å. Refinement of neutron powder diffraction data of Ce 2 TaO 1.19 N 2.81 indicated the nitrogen order in the two equatorial positions of the tantalum octahedron, with refined N/O occupancies of 0.930(7)/0.070 and 0.876(13)/0.124, and the axial position is occupied by 50% of each anion. This anion ordering agrees with the distribution predicted by Pauling's second crystal rule. Magnetization measurements show that the cerium and europium compounds are ordered magnetically at low temperatures, while the neodymium compound remains paramagnetic down to 2 K, as a consequence of suppression of the effective magnetic moment of the latter when reducing the temperature., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Europium tantalum perovskite oxynitrides were prepared by a new high-temperature solid-state synthesis under N 2 or N 2 /H 2 gas. The nitrogen stoichiometry was tuned from 0.63 to 1.78 atoms per Eu or Ta atom, starting with appropriate N/O ratios in the mixture of the reactants Eu 2 O 3 , EuN and Ta 3 N 5 , or Eu 2 O 3 and TaON, which was treated at 1200 °C for 3 h. Two phases were isolated with compositions EuTaO 2.37 N 0.63 and Eu 3 Ta 3 O 3.66 N 5.34 , showing different crystal structures and magnetic properties. Electron diffraction and Rietveld refinement of synchrotron radiation X-ray diffraction indicated that EuTaO 2.37 N 0.63 is a simple perovskite with cubic Pm 3̅ m structure and cell parameter a = 4.02043(1) Å, whereas the new compound Eu 3 Ta 3 O 3.66 N 5.34 is the first example of a triple perovskite oxynitride and shows space group P 4/ mmm with crystal parameters a = 3.99610(2), c = 11.96238(9) Å. The tripling of the c-axis in this phase is a consequence of the partial ordering of europium atoms with different charges in two A sites of the perovskite structure with relative ratio 2:1, where the formal oxidation states +3 and +2 are respectively dominant. Magnetic data provide evidence of ferromagnetic ordering developing at low temperatures in both oxynitrides, with saturation magnetization of about 6 μ B and 3 μ B per Eu ion for EuTaO 2.37 N 0.63 and the triple perovskite Eu 3 Ta 3 O 3.66 N 5.34 respectively, and corresponding Curie temperatures of about 7 and 3 K, which is in agreement with the lower proportion of Eu 2+ in the latter compound.

The development of new synthetic methodologies of perovskite oxynitrides is challenging but necessary for the search of new compounds and the investigation of new properties. Here, we report a new method of preparation of the perovskite LaTaON 2 that has been investigated as a pigment and photocatalyst for water splitting. The synthesis proceeds through the solid-state reactions under N 2 at 1500 °C between La 2 O 3 , LaN, and Ta 3 N 5 or between LaN and TaON, which are completed after 3 h and lead to sintered, highly crystalline samples with particle sizes up to 1 μm. Nitrogen-deficient samples LaTaO 1+ x N 2- x with x ≤ 0.35 are prepared by changing the N/O ratio in the mixture of reactants. Electron diffraction, synchrotron diffraction, and neutron diffraction studies on stoichiometric and nitrogen-deficient compounds indicate that they crystallize in the monoclinic space group I 2/ m with lattice parameters for LaTaON 2 of a = 5.71458(7), b = 8.05987(10), c = 5.74772(6) Å, and β = 89.982(3)°. The three anion sites of the I 2/ m structure are partially occupied by oxygen and nitrogen, with a preference of nitride for two positions with occupancies of 77 and 88%. This anion distribution is different from that reported in previous studies of samples prepared by ammonolysis at lower temperature, suggesting that the synthesis conditions affect the anion order of this perovskite. Optical measurements indicate a band gap of about 1.9 eV, which is close to that observed in samples prepared by other methods. The determined dielectric permittivity for LaTaON 2 ε r ≈ 200, reported for the first time for a highly nitrided pseudocubic perovskite, is similar to that observed in perovskites with one nitrogen per formula.

Ferroelectric oxides have attracted much attention due to their wide range of applications, particularly in electronic devices such as nonvolatile memories and tunnel junctions. As a result, the monolithic integration of these materials into silicon technology and their nanostructuration to develop alternative cost-effective processes are among the central points in the current technology. In this work, we used a chemical route to obtain nanowire thin films of a novel Sr1+δMn8O16 (SMO) hollandite-type manganese oxide on silicon. Scanning transmission electron microscopy combined with crystallographic computing reveals a crystal structure comprising hollandite and pyrolusite units sharing the edges of their MnO6 octahedra, resulting in three types of tunnels arranged along the c axis, where the ordering of the Sr atoms produces natural symmetry breaking. The novel structure gives rise to ferroelectricity and piezoelectricity, as revealed by local direct piezoelectric force microscopy measurements, which confirmed the ferroelectric nature of the SMO nanowire thin films at room temperature and showed a piezoelectric coefficient d33 value of 22 ± 6 pC N-1. Moreover, we proved that flexible vertical SMO nanowires can be harvested providing an electrical output energy through the piezoelectric effect, showing excellent deformability and high interface recombination. This work indicates the possibility of engineering the integration of 1D manganese oxides on silicon, a step which precedes the production of microelectronic devices.

Non-centrosymmetric polar compounds have important technological properties. Reported perovskite oxynitrides show centrosymmetric structures, and for some of them high permittivities have been observed and ascribed to local dipoles induced by partial order of nitride and oxide. Reported here is the first hexagonal perovskite oxynitride BaWON 2 , which shows a polar 6H polytype. Synchrotron X-ray and neutron powder diffraction, and annular bright-field in scanning transmission electron microscopy indicate that it crystalizes in the non-centrosymmetric space group P6 3 mc, with a total order of nitride and oxide at two distinct coordination environments in cubic and hexagonal packed BaX 3 layers. A synergetic second-order Jahn-Teller effect, supported by first principle calculations, anion order, and electrostatic repulsions between W 6+ cations, induce large distortions at two inequivalent face-sharing octahedra that lead to long-range ordered dipoles and spontaneous polarization along the c axis. The new oxynitride is a semiconductor with a band gap of 1.1 eV and a large permittivity., (© 2020 Wiley-VCH GmbH.)

Magnetic particle hyperthermia, in which colloidal nanostructures are exposed to an alternating magnetic field, is a promising approach to cancer therapy. Unfortunately, the clinical efficacy of hyperthermia has not yet been optimized. Consequently, routes to improve magnetic particle hyperthermia, such as designing hybrid structures comprised of different phase materials, are actively pursued. Here, we demonstrate enhanced hyperthermia efficiency in relatively large spherical Fe/Fe-oxide core-shell nanoparticles through the manipulation of interactions between the core and shell phases. Experimental results on representative samples with diameters in the range 30-80 nm indicate a direct correlation of hysteresis losses to the observed heating with a maximum efficiency of around 0.9 kW/g. The absolute particle size, the core-shell ratio, and the interposition of a thin wüstite interlayer are shown to have powerful effects on the specific absorption rate. By comparing our measurements to micromagnetic calculations, we have unveiled the occurrence of topologically nontrivial magnetization reversal modes under which interparticle interactions become negligible, aggregates formation is minimized and the energy that is converted into heat is increased. This information has been overlooked until date and is in stark contrast to the existing knowledge on homogeneous particles., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Reduced graphene oxide (RGO) decorated with superparamagnetic iron oxide nanoparticles (SPION) is a novel composite nanomaterial with a myriad of promising applications. However, processes such as the fast and simple synthesis of non-agglomerated monodispersed SPION on RGO and the accurate characterization of particle size distributions remain challenging. Here we present how to solve these two problems. Firstly, we introduce a new microwave-assisted synthesis of stabilized SPION on RGO which is fast, simple and up-scalable but at the same time renders well dispersed SPION with narrow size distributions. The coverage of the RGO flakes with SPION is extensively tuned and the results are compared with a non-stabilized microwave-assisted method. Secondly, we implement an accurate method for the determination of particle size distributions from magnetization curves in RGO-SPION composite nanomaterials. This method is applied to the prepared composites with different particle size distributions, degrees of particle agglomeration and coverage of the RGO flakes. The influence of sample characteristics in the size determination method is discussed and the results are compared with the values obtained from transmission electron microscopy (TEM) and X-ray diffraction (XRD), showing that the method is well suited for these and potentially other types of superparamagnetic composite nanomaterials., 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 © 2020 Elsevier Inc. All rights reserved.)

The monolithic integration of sub-micron quartz structures on silicon substrates is a key issue for the future development of piezoelectric devices as prospective sensors with applications based on the operation in the high-frequency range. However, to date, it has not been possible to make existing quartz manufacturing methods compatible with integration on silicon and structuration by top-down lithographic techniques. Here, we report an unprecedented large-scale fabrication of ordered arrays of piezoelectric epitaxial quartz nanostructures on silicon substrates by the combination of soft-chemistry and three lithographic techniques: (i) laser interference lithography, (ii) soft nanoimprint lithography on Sr-doped SiO 2 sol-gel thin films, and (iii) self-assembled SrCO 3 nanoparticle reactive nanomasks. Epitaxial α-quartz nanopillars with different diameters (from 1 μm down to 50 nm) and heights (up to 2 μm) were obtained. This work demonstrates the complementarity of soft-chemistry and top-down lithographic techniques for the patterning of epitaxial quartz thin films on silicon while preserving its epitaxial crystallinity and piezoelectric properties. These results open up the opportunity to develop a cost-effective on-chip integration of nanostructured piezoelectric α-quartz MEMS with enhanced sensing properties of relevance in different fields of application.

Magnetic resonance imaging (MRI) is a useful tool for disease diagnosis and treatment monitoring. Superparamagnetic iron oxide nanoparticles (SPION) show good performance as transverse relaxation (T 2 ) contrast agents, thus facilitating the interpretation of the acquired images. Attachment of SPION onto nanocarriers prevents their agglomeration, improving the circulation time and efficiency. Graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (RGO), are appealing nanocarriers since they have both high surface area and functional moieties that make them ideal substrates for the attachment of nanoparticles. We have employed a fast, simple and environmentally friendly microwave-assisted approach for the synthesis of SPION-RGO hybrids. Different iron precursor/GO ratios were used leading to SPION, with a median diameter of 7.1 nm, homogeneously distributed along the RGO surface. Good relaxivity (r 2 *) values were obtained in MRI studies and no significant toxicity was detected within in vitro tests following GL261 glioma and J774 macrophage-like cells for 24 h with SPION-RGO, demonstrating the applicability of the hybrids as T 2 -weighted MRI contrast agents.

Knowing the interactions controlling aggregation processes in magnetic nanoparticles is of strong interest in preventing or promoting nanoparticles' aggregation at wish for different applications. Dipolar magnetic interactions, proportional to the particle volume, are identified as the key driving force behind the formation of macroscopic aggregates for particle sizes above about 20 nm. However, aggregates' shape and size are also strongly influenced by topological ordering. 1-D macroscopic chains of several micrometer lengths are obtained with cube-shaped magnetic nanoparticles prepared by the gas-aggregation technique. Using an analytical model and molecular dynamics simulations, the energy landscape of interacting cube-shaped magnetic nanoparticles is analysed revealing unintuitive dependence of the force acting on particles with the displacement and explaining pathways leading to their assembly into long linear chains. The mechanical behaviour and magnetic structure of the chains are studied by a combination of atomic and magnetic force measurements, and computer simulation. The results demonstrate that [111] magnetic anisotropy of the cube-shaped nanoparticles strongly influences chain assembly features.

Layered CaTaN 2 and MgTa 2 N 3 and cubic Mg 2 Ta 2 N 4 were prepared by direct solid state reaction from the binary nitrides Ta 3 N 5 and A 3 N 2 (A: Mg, Ca). CaTaN 2 showed a slight Ca deficiency (0.11 moles per formula), and a monoclinic distortion from previously reported R 3̅ m symmetry, with space group C 2/ m and cell parameters a = 5.4011(2), b = 3.1434(1), c = 5.9464(2) Å and β = 107.91(3)°. Ca 2+ and Mg 2+ deintercalation was investigated in the three compounds both chemically and electrochemically. No significant Mg 2+ extraction could be inferred for MgTa 2 N 3 and Mg 2 Ta 2 N 4 , neither after reaction with NO 2 BF 4 nor after electrochemical oxidation at 100 °C in alkyl carbonate electrolytes. Rietveld refinement of the X-ray powder diffraction pattern of chemically oxidized Ca 0.89 TaN 2 indicates a decrease of the Ca content to 0.34 concomitant to the disappearance of the monoclinic distortion and expansion of the interlayer space from 5.658 to 5.762 Å, space group R 3̅ m and cell parameters a = 3.1103(1) and c = 17.287(1) Å. Deintercalation in this compound was also achieved electrochemically at 100 °C. Results of density functional theory calculations seem to indicate that reaction mechanisms for CaTaN 2 oxidation additional and/or alternative to deintercalation are taking place, which is likely related to the loss of crystallinity observed upon oxidation and the irreversibility of the process., Competing Interests: The authors declare no competing financial interest.

The topotactic nitridation of cation ordered, tetragonal Sr2FeMoO6 in NH3 at moderate temperatures leads to cubic, Fm3[combining macron]m double perovskite oxynitride Sr2FeMoO4.9N1.1 where double-exchange interactions determine ferromagnetic order with TC ≈ 100 K. Substitution of oxide by nitride induces bond asymmetries and local electronically driven structural distortions, which combined with Fermi level lowering restricts charge itinerancy to confined regions and preclude spontaneous long-range magnetic order. Under a magnetic field, ferromagnetic correlations expand, favoring charge delocalization and a negative magnetoresistance is observed.

A simple crossover from two-dimensional to three-dimensional correlated disorder of O and N atoms on a cubic lattice has been discovered within the Ba1-xSrxTaO2N series of perovskite oxynitrides. The crossover is driven by lattice expansion as x decreases, and provides a rapid increase in entropy due to a change from subextensive to extensive configurational entropy regimes.

Topochemical nitridation in ammonia at moderate temperatures of cation ordered Sr 2 FeWO 6 produces new antiferromagnetic double perovskite oxynitrides Sr 2 FeWO 6-x N x with 0 < x ≤ 1. Nitrogen introduction induces the oxidation of Fe 2+ to Fe 3+ and decreases T N from 38 K (x = 0) to 13 K for Sr 2 FeWO 5 N which represents the first example of a double perovskite oxynitride with both high cationic order and nitrogen content. This synthetic approach can be extended to other cation combinations expanding the possibility of new materials in the large group of double perovskites.

Ag 2 Cu 3 Cr 2 O 8 (OH) 4 , a new Ag-Cu-Cr-O layered mixed oxide, prepared by soft hydrothermal heterogeneous reactions, is reported. The new phase is an oxyhydroxide and presents a structure with alternating brucite-like Cu-O and Ag-O layers connected by individual chromate groups. The crystallographic structure has been solved and refined from high resolution powder X-ray diffraction data and is supported by density functional theory calculations, yielding a triclinic, space group P1[combining macron], a = 5.3329(1) Å, b = 5.3871(1) Å, c = 10.0735(1) Å, α = 80.476(1)°, β = 87.020(1)°, γ = 62.383(1)°. Bond valence sums suggest the formulation of Ag + 2 Cu 2+ 3 Cr 6+ 2 O 8 (OH) 4 , an electronic state fully supported by X-ray photoelectron spectroscopy (XPS) and Cr K-edge X-ray absorption near edge structure (XANES) measurements. Ag 2 Cu 3 Cr 2 O 8 (OH) 4 exhibits bidimensional Cu-O-Cu ferromagnetic correlations that are apparent at much higher temperatures than in other similar Cu-O layered structures, without coupling between Cu-O layers, which represents a unique case in the recent family of silver copper oxides. The role of Ag inducing bidimensionality in copper oxides is therefore expanded further with the presence of chromate anions. Ab initio calculations using density functional theory show that the electronic states involved originate mainly from Cu and OH orbitals, with minor contributions from Cr and the O atoms linking the Cr tetrahedra to the brucitic Cu-O layer, and almost no contribution from Ag. Further modeling of the in-plane magnetic interactions between Cu atoms suggests that the coupled magnetized stripes are responsible for the observed behavior. The results are discussed in relation with previous Ag-Cu mixed oxide phases where metallic behavior or ferro-antiferro transitions had been observed. The structure of this new Ag-Cu-O phase as compared with previous silver copper oxides supports the conclusion that the Ag-Cu layered ordering is favored under oxidizing conditions.

The fabrication procedure of hollow iron oxide nanoparticles with a large surface to volume ratio by a single-step gas condensation process at ambient temperature is presented. Fe clusters formed during the sputtering process are progressively transformed into hollow cuboids with oxide shells by the Kirkendall mechanism at the expense of oxygen captured inside the deposition chamber. TEM and Raman spectroscopy techniques point to magnetite as the main component of the nanocuboids; however, the magnetic behavior exhibited by the samples suggests the presence of FeO as well. In addition, these particles showed strong stability after several months of exposure to ambient conditions, making them of potential interest in diverse technological applications. In particular, these hierarchical hollow particles turned out to be very efficient for both As(III) and As(V) absorption (326 and 190 mg/g, respectively), thus making them of strong interest for drinking water remediation.

LnCrO(3-x)N(x) perovskites with Ln = La, Pr and Nd and nitrogen contents up to x = 0.59 have been synthesised through ammonolysis of LnCrO4 precursors. These new materials represent one of the few examples of chromium oxynitrides. Hole-doping through O(2-)/N(3-) anion substitution suppresses the magnetic transition far less drastically than Ln(3+)/M(2+) (M = Ca, Sr) cation substitutions because of the greater covalency of metal-nitride bonds. Hence, nitride-doping is a more benign method for doping metal oxides without suppressing electronic transitions.

The new compounds LaSrSiO3N and LaBaSiO3N activated with Eu(2+) are orange-red light-emitting luminescent materials under excitation in the UV-blue range. They represent the first examples of stoichiometric alkaline earth oxynitridosilicates with a β-K2SO4 structure. The isostructural compound LaEuSiO3N is ferromagnetic with a Curie temperature of 3 K and also shows red luminescence (λmax = 705 nm) under excitation at 405 nm.