Preparazione e caratterizzazione di compositi polimerici funzionali a base di nanostrutture carboniose

Obiettivo di questo lavoro è la realizzazione di materiali nanocompositi polimerici utilizzando come matrice la resina epossidica commerciale Epikote828 e come filler nanotubi di carbonio (CNT) e nanoplacchette di grafene (GNP) e la caratterizzazione funzionale per applicarli come schermi per interferenze elettromagnetiche. Per correlare le proprietà funzionali alle proprietà morfologico-strutturali, i materiali sono stati analizzati mediante microscopia acustica a scansione (SAM) per valutare la dispersione del filler, spettroscopia Raman e per verificare risonanza magnetica nucleare in stato solido (ss-NMR) per studiare le interazioni filler-matrice e test di nanoindentazione per studiare l’effetto della presenza dei filler sulla struttura della matrice. Le proprietà morfologico-strutturali dei compositi, quindi, sono state correlate alle proprietà dielettriche ed elettromagnetiche mediante spettroscopia dielettrica: si è studiata la variazione della costante dielettrica e il comportamento come schermo per le microonde al variare della concentrazione di filler. Si è trovato che: -la struttura dei filler non viene modificata durante il trattamento effettuato per la preparazione dei materiali, ciò è stato evidenziato dalla spettroscopia Raman; -l’aggiunta dei filler carboniosi modifica le proprietà della matrice migliorandone le proprietà meccaniche, come riscontrato dai test di nanoindentazione e dai tempi di rilassamento ottenuti dalla tecnica di ss-NMR; -tra i filler, i CNT hanno migliorato più efficacemente le proprietà meccaniche (~50% della durezza rispetto alla matrice pura); -le proprietà dielettriche ed elettromagnetiche dei nanocompositi testate mediate analizzatore di impedenza e analizzatore di rete vettoriale sono esaltate dalla presenza dei filler carboniosi -tra i nanocompositi i materiali caricati con GNP manifestano le migliori proprietà schermanti (abbattimento di ~80% della radiazione incidente) Le differenze sono state associate al cambiamento di dimensionalità, unidimensionale (1D) per i CNT e bidimensionale per le GNP (2D). La struttura bidimensionale consente la formazione di un network più esteso rispetto alla struttura unidimensionale a parità di concentrazione che migliora ed esalta le proprietà di schermatura elettromagnetica

APPROCCIO CLINICO E RIABILITATIVO AL PAZIENTE PROTESIZZATO D'ARTO INFERIORE

Nella chirurgia sostitutiva protesica, ripercorrendo le tappe riabilitative e analizzandone le modalità e le tecniche, si evince che è possibile permettere al paziente il riapprendimento della corretta deambulazione con la riorganizzazione di tutte le fasi e della gestualità corrente per il reinserimento efficace nel contesto sociale di appartenenza. Oltre che dal punto di vista puramente motorio, il soggetto deve essere seguito anche sotto l’aspetto della psicomotricità e nel rispetto di importanti esigenze psicologiche. Viene sorretto, incoraggiato, ma soprattutto responsabilizzato sul fatto che per la ripresa completa si rende indispensabile la sua partecipazione attiva e la costanza dell’impegno. I riflessi pratici di una guarigione efficace e completa sono quindi estremamente proficui per il soggetto, il quale avverte in sé la capacità di ottemperare all’impegno del proprio recupero; seppur con stati d’ansia che insidiano il suo equilibrio, egli tenderà a proiettarsi nel suo futuro che quindi non apparirà denso di incognite. Non vi sarà commiserazione né emarginazione, ma voglia di vivere in una società che, anche se disumanizza i rapporti fra le differenti fasce di età, offre interessi e spazi per quanti sappiano organizzare la propria esistenza senza frustrazioni, remore e tentennamenti. La riabilitazione del protesizzato è un processo complesso perché non riguarda solamente il recupero della funzionalità della singola articolazione ma è rivolto a un riaddestramento globale del soggetto a una nuova modalità di vita relazionale. Il programma riabilitativo, quindi, deve essere personalizzato sul singolo e deve proporsi obiettivi differenti in base alle condizioni generali (anche cognitive). È necessario rendere possibile il raggiungimento di un livello di autosufficienza e autonomia motoria tale da permettere il ritorno alle normali attività di vita quotidiana

Hydrocarbons removal from wastewater by adsorption onto biochar from Posidonia oceanica

Environmental pollution by petroleum derivatives is a very current topic. In particular, low concentration of this kind of pollutants can seriously compromise the life of animals and plants of aquatic ecosystems [1]. For this reason, recent environmental legislation imposes severe restriction to oil-in-water content for overboard discharge with concentration limits from 15 to 5 ppm [2]. The shipping industry is trying to adapt to these directives by equipping ships with cleaning treatment devices in which there are several oil removal steps. Usually, the last step of bilge water treatment is based on adsorption onto suitable adsorbent materials that must be able to remove the last and most dispersed oil fraction reducing its concentration within legal limits. In this work, a biochar obtained from pyrolysis of Posidonia oceanica, a Mediterranean sea plant, has been tested as adsorbent material of a synthetic bilge water. The pristine biochar (BCP) was tested as it was and after two chemical activation treatments with sulfuric acid (BCA) and potassium hydroxide (BCB). The adsorbent materials have been characterized by using different techniques (TGA, SEM-EDAX, FT-IR, etc) and their adsorption capacity was studied by batch and column experiments. Oil concentration measurements were performed by using: HPLC-FLD and TOC techniques

Predicting the 2000-m rowing ergometer performance from anthropometric, maximal oxygen uptake and 60-s mean power variables in national level young rowers

Many studies reported various relationships between 2000-m rowing performance and anthropometric as well as metabolic variables, however, little is known about 60-s mean power in elite youth athletes. The aim of this study was to develop different regression models to predict 2000-m rowing indoor performance time (t2000)using anthropometric variables, maximal oxygen uptake (VO2max) and mean power established during a 60-s all-out test (W60) in national elite youth rowers. Fifteen youth male Italian rowers (age: 15.7 \ub1 2.0 years; body height: 176.0 \ub1 8.0 cm; body mass: 71.2 \ub1 10.0 kg) performed an incremental maximal test, a 60-s all-out test and a 2000-m race simulation using a Concept2 rowing ergometer to assess VO2max, W60and t2000, respectively. The relationships of all variables with t2000 were investigated through Pearson\u2019s correlation. Multiple regression analyses were used to verify the best prediction model of 2000-m indoor rowing performance. The reliability of these models was expressed by R2 and the standard error of estimate. The results showed that t2000 was significantly correlated with all the examined variables, except for VO2max/body mass and age, and exhibited the significantly highest relationship with W60 (r = -0.943). The combination of anthropometric, VO2max and W60 variables was found to be the most reliable equation to predict t2000 (R2 = 0.94, SEE = 6.4). W60 measure should be considered when monitoring the rower\u2019s capability to perform high-intensity phases, important during the race\u2019s fast start and end. Not requiring expensive equipment and long duration, a 60-s all-out test could be considered a valuable tool for predicting 2000-m performance of elite youth rowers

Advanced Video-Based Processing for Low-Cost Damage Assessment of Buildings under Seismic Loading in Shaking Table Tests

This paper explores the potential of a low-cost, advanced video-based technique for the assessment of structural damage to buildings caused by seismic loading. A low-cost, high-speed video camera was utilized for the motion magnification processing of footage of a two-story reinforcedconcrete frame building subjected to shaking table tests. The damage after seismic loading was estimated by analyzing the dynamic behavior (i.e., modal parameters) and the structural deformations of the building in magnified videos. The results using the motion magnification procedure were compared for validation of the method of the damage assessment obtained through analyses of conventional accelerometric sensors and high-precision optical markers tracked using a passive 3D motion capture system. In addition, 3D laser scanning to obtain an accurate survey of the building geometry before and after the seismic tests was carried out. In particular, accelerometric recordings were also processed and analyzed using several stationary and nonstationary signal processing techniques with the aim of analyzing the linear behavior of the undamaged structure and the nonlinear structural behavior during damaging shaking table tests. The proposed procedure based on the analysis of magnified videos provided an accurate estimate of the main modal frequency and the damage location through the analysis of the modal shapes, which were confirmed using advanced analyses of the accelerometric data. Consequently, the main novelty of the study was the highlighting of a simple procedure with high potential for the extraction and analysis of modal parameters, with a special focus on the analysis of the modal shape’s curvature, which provides accurate information on the location of the damage in a structure, while using a noncontact and low-cost method

Redox and autonomic responses to acute exercise-post recovery following Opuntia ficus-indica juice intake in physically active women

Background: The aim of this study was to investigate if the supplementation with Opuntia ficus-indica (OFI) juice may affect plasma redox balance and heart rate variability (HRV) parameters following a maximal effort test, in young physically active women. Methods: A randomized, double blind, placebo controlled and crossover study comprising eight women (23.25 ± 2.95 years, 54.13 ± 9.05 kg, 157.75 ± 0.66 cm and BMI of 21.69 ± 0.66 kg/m2) was carried out. A juice containing OFI diluted in water and a Placebo solution were supplied (170 ml; OFI = 50 ml of OFI juice + 120 ml of water; Placebo = 170 ml beverage without Vitamin C and indicaxanthin). Participants consumed the OFI juice or Placebo beverage every day for 3 days, before performing a maximal cycle ergometer test, and for 2 consecutive days after the test. Plasma hydroperoxides and total antioxidant capacity (PAT), Skin Carotenoid Score (SCS) and HRV variables (LF, HF, LF/HF and rMSSD) were recorded at different time points. Results: The OFI group showed significantly lower levels of hydroperoxides compared to the Placebo group in pretest, post-test and 48-h post-test. PAT values of the OFI group significantly increased compared to those of the Placebo group in pre-test and 48-h post-test. SCS did not differ between groups. LF was significantly lower in the OFI group 24-h after the end of the test, whereas rMSSD was significantly higher in the OFI group 48-h post-test. Conclusion: OFI supplementation decreased the oxidative stress induced by intense exercise and improved autonomic balance in physically active women

Relationship between wingate cycle test and 2000m rowing ergometer performance in youth athletes

During 2000m indoor rowing performances, the estimated aerobic and anaerobic contribution are 65-75% and 25-35%, respectively2. In considering that anaerobic power could be an important predictor of performance1, the aim of this study was to analyse the relationship between the power outputs during a Wingate anaerobic test (WAnT) on a cycling ergometer and a 2000m rowing ergometer performance in young rowers. In two separate days, 11 young (14.9±1.1yrs) male rowers performed a 2000m indoor rowing ergometer performance and a 30s WAnT on a cycling ergometer. WAnT peak power (PP) and mean power (MP), and 2000m time indoor rowing performance (t2000) were collected. Moreover, PP and MP were normalized with respect to body mass. Pearson correlation coefficients (r) were used to determine the association between t2000 and absolute and normalized PP and MP values. Absolute PP and MP were 888.1±133.2W and 548.5±74.4W, respectively. The relative picture for normalized values was 13.4±1.5 W·kg-1 and 8.2±0.6 W·kg-1. High associations emerged between t2000 (431.5±19.5s) and absolute PP (r=-0.900, P=0.05) values, whereas no significant relationship was observed for normalized PP (r=-0.585, P=0.058) and AP (r=-0.561, P=0.072) values. These findings indicate that PP and MP could be considered significant predictors of 2000m rowing ergometer performances, substantiating also the relevance of the anaerobic energy pathways to the 2,000m rowing performance

Oxidized Alginate Dopamine Conjugate: In Vitro Characterization for Nose‐to‐Brain Delivery Application

Background: The blood–brain barrier (BBB) bypass of dopamine (DA) is still a challenge for supplying it to the neurons of Substantia Nigra mainly affected by Parkinson disease. DA prodrugs have been studied to cross the BBB, overcoming the limitations of DA hydrophilicity. Therefore, the aim of this work is the synthesis and preliminary characterization of an oxidized alginate-dopamine (AlgOX-DA) conjugate conceived for DA nose-to-brain delivery. Methods: A Schiff base was designed to connect oxidized polymeric backbone to DA and both AlgOX and AlgOX-DA were characterized in terms of Raman, XPS, FT-IR, and 1H- NMR spectroscopies, as well as in vitro mucoadhesive and release tests. Results: Data demonstrated that AlgOX-DA was the most mucoadhesive material among the tested ones and it released the neurotransmitter in simulated nasal fluid and in low amounts in phosphate buffer saline. Results also demonstrated the capability of scanning near-field optical microscopy to study the structural and fluorescence properties of AlgOX, fluorescently labeled with fluorescein isothiocyanate microstructures. Interestingly, in SH-SY5Y neuroblastoma cell line up to 100 μg/mL, no toxic effect was derived from AlgOX and AlgOX-DA in 24 h. Conclusions: Overall, the in vitro performances of AlgOX and AlgOX-DA conjugates seem to encourage further ex vivo and in vivo studies in view of nose-to-brain administratio