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In the last decades, magnetic ceramics are very appealing materials that find applications in several technologic fields. Among these, iron oxides nanoparticles are the main relevant ones due to their low-cost as naturally occurring substrates. However, depending on the application, it can be necessary to induce a specific shape and size control over the final morphology, and consequently a proper synthetic route becomes mandatory. Hence, this document provides a summary of the main relevant chemical, physical, thermal, and biological methods to induce a certain degree of morphological control in iron oxides. The main focus of this document relies on highlighting the principal guidelines, unveiling both advantages and disadvantages of each method in terms of morphology control in the resulting products. Lastly, a particular emphasis has been dedicated toward the industrial feasibility of all processes here discussed. Resumen: En las últimas décadas, la cerámica magnética es un material muy atractivo que encuentra aplicaciones en varios campos tecnológicos. Entre estos, las nanopartículas de óxidos de hierro son las principales por su bajo costo como sustratos naturales. Pero, dependiendo de la aplicación, puede ser necesario inducir un control de forma y tamaño específico sobre la morfología final y, por lo tanto, una ruta sintética adecuada se vuelve obligatoria. Por esta razón, este documento ofrece un resumen de los principales métodos químicos, físicos, térmicos y biológicos relevantes para inducir un cierto grado de control morfológico en los óxidos de hierro. El objetivo principal de este documento se basa en resaltar las principales directrices, revelando las ventajas y desventajas de cada método en términos de control de la morfología en los productos resultantes. Por último, se ha dedicado un énfasis particular a la viabilidad industrial de todos los procesos aquí discutidos.

Bio-based substances (BBS) obtained from composted urban biowaste and nanosponges obtained from β-cyclodextrins (βCD) were used as green source to produce biochar via pyrolysis performed under mild conditions. Pyrolysis conditions were optimized by means of TGA analysis, and different temperatures of pyrolysis were investigated. The resulting carbonaceous materials were characterized with several physicochemical techniques (elemental analysis, FTIR spectroscopy, XRD, SEM, surface area analysis, and zeta potential measurements). Additionally, the adsorption capacity of such materials was tested toward the removal of charged dyes from aqueous environment. Isothermal experiments carried out at circumneutral pH indicated an important charge-selectivity, which encourages their use as sustainable alternative materials in wastewater purification treatments. Moreover, the analysis of the adsorption capacity as a function of specific surface area of materials suggests the strategy to obtain carbonaceous solids with enhanced capacity in capture of polar molecules.

Photo-polymerization is a polymerization method widely exploited in many technological fields, due to its high versatility and fast reaction rates. In this study, poly(ethylene glycol) methacrylate (PEGMA) nanostructures are grown onto cellulose following a simple and promising light-driven reaction mechanism involving benzophenone (as photo-initiator) and UV-curing. The effectiveness of the surface functionalization has been determined by means of morphological and physicochemical characterizations, showing the formation of very sharp PEGMA nanometric architectures.

Thermo-gravimetric analysis coupled to time/temperature-resolved FTIR spectroscopy of evolved gases was used to measure the vinyl alcohol units content in EVOH copolymer. Pure homopolymers were used as references. The quantitative analysis here proposed is based on the calculation of integral profiles relative to FTIR signals of water molecules evolved during the thermal degradation (pyrolysis) of vinyl alcohol units.

Highly-branched plasmonic nanostructures are interesting substrates to be exploited in Surface-Enhanced Raman Scattering (SERS) detection, as sources of efficient Raman “hot-spots”. In this study, l -cysteine is proposed as reducing/capping agents for the production of Ag nanonets showing different morphologies by varying the synthesis conditions. Substrates are coupled to PDMS membranes and characterized by Raman spectroscopy using 4-MBA to define their SERS performance. Experimental evidences confirm that only the thinnest structures are able to guarantee significant SERS responses.

We have investigated the relevance of d-aspartate oxidase, the only enzyme known to selectively degrade d-aspartate (d-Asp), in modulating glutamatergic system homeostasis. Interestingly, the lack of the Ddo gene, by raising d-Asp content, induces a substantial increase in extracellular glutamate (Glu) levels in Ddo-mutant brains. Consistent with an exaggerated and persistent N-methyl-d-aspartate receptor (NMDAR) stimulation, we documented in Ddo knockouts severe age-dependent structural and functional alterations mirrored by expression of active caspases 3 and 7 along with appearance of dystrophic microglia and reactive astrocytes. In addition, prolonged elevation of d-Asp triggered in mutants alterations of NMDAR-dependent synaptic plasticity associated to reduction of hippocampal GluN1 and GluN2B subunits selectively located at synaptic sites and to increase in the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-to-N-methyl-d-aspartate ratio. These effects, all of which converged on a progressive hyporesponsiveness at NMDAR sites, functionally resulted in a greater vulnerability to phencyclidine-induced prepulse inhibition deficits in mutants. In conclusion, our results indicate that d-aspartate oxidase, by strictly regulating d-Asp levels, impacts on the homeostasis of glutamatergic system, thus preventing accelerated neurodegenerative processes.

The endoplasmic reticulum (ER) stress-mediated pathway is involved in a wide range of human neurodegenerative disorders. Hence, molecules that regulate the ER stress response represent potential candidates as drug targets to tackle these diseases. In previous studies we demonstrated that upon acetylation the reticulon-1C (RTN-1C) variant of the reticulon family leads to inhibition of histone deacetylase (HDAC) enzymatic activity and endoplasmic reticulum stress-dependent apoptosis. Here, by microarray analysis of the whole human genome we found that RTN-1C is able to specifically regulate gene expression, modulating transcript clusters which have been implicated in the onset of neurodegenerative disorders. Interestingly, we show that some of the identified genes were also modulated in vivo in a brain-specific mouse model overexpressing RTN-1C. These data provide a basis for further investigation of RTN-1C as a potential molecular target for use in therapy and as a specific marker for neurological diseases.