From the history of the recognitions of the remains to the reconstruction of the face of Dante Alighieri by means of techniques of virtual reality and forensic anthropology

The work consists of the reconstruction of the face of the great poet called Dante Alighieri through a multidisciplinary approach that matches traditional techniques (manual ones), usually used in forensic anthropology, with digital methodologies that take advantage of technologies born in manufacturer-military fields but that are more and more often applied to the field of the cultural heritage. Unable to get the original skull of Dante, the work started from the data and the elements collected by Fabio Frassetto and Giuseppe Sergi, two important anthropologists, respectively at the University of Bologna and Rome, in an investigation carried out in 1921, sixth century anniversary of his death, on the remains of the poet collected in Ravenna. Thanks to this, we have a very accurate description of Dante’s bones, including 297 metric data inherent to the whole skeleton, some photographs in the scale of the skull, the various norms and many other bones, as well as a model of the skull subsequently realized by Frassetto. According to these information, a geometric reconstruction of Dante Alighieri skull including the jaw was carried out through the employment and integration of the instruments and technologies of the virtual reality, and from this the relative physical model through fast prototype was realized. An important aspect of the work regards in a particular manner the methodology of 3D modelling proposed for the new reconstruction of the jaw (not found in the course of the 1921 recognition), starting from a reference model. The model of the skull prototype is then useful as the basis for the successive stage of facial reconstruction through the traditional techniques of forensic art

solubilizzazione e valorizzazione di biopolimeri tramite liquidi ionici

In questo lavoro di tesi è stata studiata la possibilità di valorizzare biopolimeri come cheratina e chitina (prodotti come scarto in grandi quantità, principalmente nell’industria alimentare e tessile). tramite la loro solubilizzazione in liquidi ionici (IL) o dotati di gruppi funzionali polimerizzabili (PIL). Questi ultimi possono essere copolimerizzati con un monomero neutro al fine di ottenere compositi polimero/biopolimero. Un composito cheratina/polimero o chitina/polimero potrebbe sfruttare i vantaggi delle naturali proprietà di fibre di cheratina (es. resistenza a bassa densità) per creare compositi rinnovabili, biodegradabili capaci di prendere il posto di materiali preparati da fonti non rinnovabili. Le sorgenti di cheratina utilizzate sono state lana di basso pregio e piume di tacchino mentre per la chitina sono stati utilizzati gusci di gamberi. È stata sintetizzata una serie di IL e PIL in scelti in base alla loro capacità di inserirsi nelle interazioni non covalenti (legami ad idrogeno, interazioni ione-ione, interazioni idrofobiche) interne ai biopolimeri presi in esame. In seguito all’esito delle prove di solubilità in essi dei biopolimeri si è deciso di concentrarsi sulla cheratina proveniente da piume. Su una serie di soluzioni contenenti grandi quantità di cheratina disciolta (fino al 60%). Sono state quindi eseguite copolimerizzazioni con stirene. I Compositi risultanti sono stati caratterizzati tramite tecniche spettroscopiche (FTIR e NMR) e termiche (TGA, DSC)

Confronto tra nanoparticelle e gocce oftalmiche a base di derivati del chitosano per il trattamento di patologie oculari

Scopo del lavoro: valutazione del tempo di residenza medio nel fluido lacrimale (MRT) dell’occhio del coniglio di metencefalina (MET), farmaco peptidico, incapsulata in nanoparticelle (NP) a base di diversi derivati mucoadesivi del chitosano in confronto a gocce oftalmiche contenenti la stessa dose di farmaco e gli stessi polimeri usati per preparare le NP. Metodi: sono stati preparati derivati del chitosano, caratterizzati da piccole catene laterali formate da gruppi ammonici quaternari adiacenti, a partire da chitosano da noi depolimerizzato (sigla polimeri N+-rCh). Successivamente sono stati introdotti su N+-rCh gruppi tiolici attraverso la formazione di legami ammidici con acido tioglicolico per ottenere N+-rCh-SH. Con i derivati N+-rCh e N+-rCh-SH sono state preparate nanoparticelle medicate per reticolazione ionotropica con acido ialuronico depolimerizzato (rHA), aggiungendo sotto agitazione un volume misurato di soluzione acquosa di rHA e MET, a concentrazioni prestabilite, a 5 mL di soluzione di N+-rCh o N+-rCh-SH (2 mg/mL) in tampone fosfato pH 7.4. Le nanoparticelle sono state caratterizzate per le dimensioni e l’efficienza di intrappolamento. Il rilascio di MET dalle NP è stato studiato sottoponendo a dialisi le dispersioni, interrompendo le dialisi dopo 1, 3 o 5 ore e determinando per ciascuno di tali tempi la % di MET passata nella fase ricevente /FFR), quella presente nella fase donatrice ma esterna alle NP (FFD) e quella ancora associata alle NP (FNP). Le NP sono state sottoposte a dialisi anche al fine di allontanare il farmaco non intrappolato. Per ottenere formulazioni stabili e manipolabili le dispersioni nanoparticellari precedentemente sottoposte a dialisi sono state liofilizzate. Le dispersioni liofilizzate rigenerate per aggiunta di acqua e blanda agitazione contenevano 0.34 mg/mL di MET. Una goccia (50μL) di ciascuna dispersione veniva somministrata per determinare l’MRT nell’occhio del coniglio. Per confronto sono state testate nell’occhio del coniglio due soluzioni contenenti MET (0.34 mg/mL) e N+-rCh oppure N+-rCh-SH (2 mg/mL), come riferimento è stata testata una soluzione di MET (0.34 mg/mL) in tampone fosfato isotonico pH 7.4. Risultati: le dimensioni medie delle NP determinate immediatamente dopo la loro preparazione e dopo ridispersione dei loro liofilizzati erano sempre comprese nell’intervallo 250-370 nm. È possibile eliminare il farmaco non intrappolato dalle NP, sottoponendole a dialisi per cinque ore. Dallo studio del rilascio si è riscontrato che per la durata dell’esperimento la MET intrappolata non veniva rilasciata. Le NP sono risultate stabili come tali dopo 24 ore e rigenerabili dai rispettivi liofilizzati dopo 1 mese di conservazione in essiccatore a temperatura ambiente, in frigo ed in freezer a -20°C per semplice aggiunta di acqua e blando mescolamento. L’MRT ottenuto con le gocce di riferimento non era significativamente differente dalle gocce contenenti N+-rCh o N+-rCh-SH in soluzione. L’MRT ottenuto con dispersioni nanoparticellari era circa 4 volte superiore al controllo; la dispersione a base di N+-rCh-SH aveva un MRT superiore a quella a base di N+-rCh, tuttavia la differenza non era significativa. Questi dati indicano che i polimeri in soluzione, sebbene mucoadesivi, non sono in grado di aumentare il tempo di residenza di MET nell’occhio del coniglio probabilmente perché non sono in grado di proteggere MET dalla degradazione da parte degli enzimi presenti nel fluido lacrimale. Conclusioni: le dispersioni nanoparticellari liofilizzate possono essere considerate formulazioni maneggevoli per applicazione oftalmica e un valido veicolo per aumentare il tempo di residenza di MET nel fluido lacrimale

New eco-composites based on polyhydroxyalkanoates (PHA) for marine applications

Bio-based polymers have attracted increasing attention over the last two decades, predominantly due to their environmental friendly nature and no dependence on petroleum resources. This type of polymers has got a growing consideration which has been so far focused specifically on starch based products, PLA (Polylactic acid), PHA (Polyhydroxylalkanoates) in particular PHB (Polyhydroxyl butyrate), cellulose derived plastics, etc. The production of these materials is based on renewable agricultural and biomass feedstocks. The degradability of bio-based materials not just in compost but also in different natural environments is an important property for sustainability and reduction of plastic pollution. In this work, blends of PHA and PHB with Posidonia Oceanica fibres were investigated to assess the feasibility of producing materials biodegradable in marine environment, varying the fiber percentage from 10 to 30 wt%. The chemical composition of the Posidonia O. fiber is similar to that of other lignocellulosic materials. It consists mainly of cellulose, hemicellulose, and lignin. Thermal, rheological, mechanical and morphological characterization of the developed PHA/PHB-fibre blends has been conducted in order to investigate the effect of the fibres on their processability and tensile properties. Biodegradability of the produced composites has been investigated in sea water in view of their use in marine environment

Biopolyesters and bio based additives based blends and composites for application in packaging and agriculture

The utilization of “bio-polymers” for the production of “bio-plastic” is worldwide an assessed priority with the aim of reducing dependence from petro sources, and handle the concern for disposal of waste generated from not degradable plastics Biobased polyesters such as Polyhydroxyalkanoates (PHAs) and Polylactide (PLA) are promising biobased, compostable polymer suitable for replacing petro-derived polymer for several single use applications but are addressed even for durable materials requiring more demanding technical performances [1,2], in particular in terms of mechanical properties and stability. Consequently a better knowledge of the crystallization behavior of PLA [3] and PHAs, and its effects on the mechanical properties is crucial in order to extend bio polyesters industrial applications, and even for optimization of polymeric matrices to be further used for biocomposite or active packaging production. In the present study we have addressed the use of biobased biodegradable reactive plasticizers for production of PLA based films by blow moulding [4], and the production of biocomposites with either PLA or PHA based polymeric matrices and natural fibres such as wood, bran, and Posidonia oceanica [5]. Those studies were inserted in the activites of Regional project PHA (Project POR FESR 2014-2020) addressing production of pots and items degradable even in soil and marine water, and of the European Union’s Horizon2020, Project AGRIMAX GA: n° 720719, addressing valorization of agriculture biomass (tomato, olive, potato, bran) for different ranges of applications including biocomposites. Pla based films were produced by use of functional plasticizers derived from soy bean oils, or from cardanol, with properties comparable to polypropylene or high density polyethylene. Biocomposites were produced with either PLA or PHA polymeric matrices with up to 30% by weight of natural fibres

Effect of the addition of natural rice bran oil on the thermal, mechanical, morphological and viscoelastic properties of poly(Lactic Acid)

For the first time in this study, the utilization of rice bran oil (RBO) as possible totally eco-friendly plasticizer for poly(lactic acid) (PLA) has been investigated. For comparison, the behavior of soybean oil (SO) has also been analyzed. Both oils are not completely miscible with PLA. However, certain compatibility exists between PLA and (i) RBO and (ii) SO, because demixing is not complete. Although not totally miscible, RBO and SO are able to reduce the viscosity of the PLA+RBO and PLA+SO mixtures, which attests that a small amount of RBO or SO can be successfully added to PLA to improve its processability. Additionally, the mechanical properties of the PLA+RBO and PLA+SO mixtures exhibit trends typical of plasticizer-polymer systems. More interestingly, RBO was found to accelerate the growth of PLA α'-crystals at a low crystallization temperature. This feature is appealing, because the α'-phase presents lower elastic modulus and higher permeability to water vapor in comparison to the α-phase, which grows at high temperatures. Thus, this study demonstrates that the addition of RBO to PLA in small percentages is a useful solution for a faster preparation of PLA materials containing mainly the α'-phase

Niveles de plomo en los individuos de la necrópolis tardorromana de la c/ Virgen de la Misericordia (Valencia)

El objetivo general de este estudio ha sido determinar los contenidos de plomo (Pb) en restos de huesos y suelos de la necrópolis de la c/ Virgen de la Misericordia (Valencia) para reconstruir el proceso de transición del elemento (desde el sedimento hacia los huesos y viceversa) debido a la acción de los procesos diagenéticos

New Bio-Composites Based on Polyhydroxyalkanoates and Posidonia oceanica Fibres for Applications in a Marine Environment

Bio-composites based on polyhydroxyalkanoates (PHAs) and fibres of Posidonia oceanica (PO) were investigated to assess their processability by extrusion, mechanical properties, and potential biodegradability in a natural marine environment. PHAs were successfully compounded with PO fibres up to 20 wt%while, at 30 wt%of fibres, the addition of 10 wt%of polyethylene glycol (PEG 400) was necessary to improve their processability. Thermal, rheological, mechanical, and morphological characterizations of the developed composites were conducted and the degradation of composite films in a natural marine habitat was evaluated in a mesocosm by weight loss measure during an incubation period of six months. The addition of PO fibres led to an increase in stiffness of the composites with tensile modulus values about 80% higher for composites with 30 wt % fibre (2.3 GPa) compared to unfilled material (1.24 GPa). Furthermore, the impact energy markedly increased with the addition of the PO fibres, from 1.63 (unfilled material) to 3.8 kJ/m2 for the composites with 30 wt % PO. The rate of degradation was markedly influenced by seawater temperature and significantly promoted by the presence of PO fibres leading to the total degradation of the film with 30 wt % PO in less than six months. The obtained results showed that the developed composites can be suitable to manufacture items usable in marine environments, for example, in natural engineering interventions, and represent an interesting valorisation of the PO fibrous wastes accumulated in large amounts on coastal beaches

Biocomposites Based on Polyhydroxyalkanoates and Natural Fibres from Renewable Byproducts

Background and Objective: The use of biopolyesters and natural fibres or fillers for production of biobased composites has attracted interest of various application sectors ranging from packaging to automotive components and other high value applications in agreement with a bioeconomy approach. In the present paper biobased composites were produced by using compostable polymers degradable even in soil and marine water such as polyhydroxyalkanoates with natural fibres or fillers derived by food wastes (legumes by-products) and by wood industry.Material and Methods: Polyhydroxyalkanoates were processed with a biobased, biodegradable plasticizer such as acetyltributylcitrate and calcium carbonate as inorganic filler. The selected polymeric matrix was used for the production of composites with variable amounts of natural fibres. Green composites were manufactured by extrusion and injection moulding. Thermal, rheological, mechanical and morphological characterizations of the developed composites were performed.Results and Conclusion: The bio composites properties match the requirements for production of rigid food packaging or other single use items where the market is looking for more sustainable solutions versus the products actually used and hardly recyclable, opening a route for valorization of food residue. Pukanzsky’s model predicts with good accuracy the tensile behavior of the composites showing a medium intensity adhesion between fibres and polymer matrix in both cases analyzed.Conflict of interest: The authors declare no conflict of interest.

Evaluation of the activity of natural phenolic antioxidants, extracted from industrial coffee residues, on the stability of poly(1,4‐butylene succinate) formulations

In this work, the evaluation of the antioxidant activity of natural phenolic compounds is performed and compared to that of a conventional antioxidative agent. Phenolic molecules, extracted from industrial processing coffee residues, are added to a matrix of poly(1,4-butylene succinate) (PBS). The apparent activation energy (Ea) of the thermo-oxidative degradation is calculated by employing different methods like Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa and Friedman. The results are compared with the antioxidant activity evaluation obtained through the ABTS radical scavenging assay. From the average activation energies, it is observed that the addition of the natural antioxidants led to an increase in the activation energy of the degradation process as a function of the phenolic compound content. This trend is confirmed by the results of the ABTS assay. Hence, this study proves that the active molecules extracted from agri-food waste could be employed to improve the antioxidant capacity of the biopolymer, even if the composition of the extract must be evaluated in order to mitigate the effects of other components