Models and Systems for the control of two-phase processes in microfluidics

Microfluidics is a novel and promising scientific field research whose progresses are aimed to the development of the Lab-On-Chip (LOC) systems. The strong point of the microfluidics is the ability to miniaturize and integrate one or several laboratory functions on the same device, to have a portable and user-friendly instrument. Most applications require accurate measures and control within the microfluidic channels. In this thesis, the optical techniques were adopted to monitor, sensing and control the processes, leading to the research area of optofluidics that are based on the integration of fluidics and optics. To reduce the cost, to develop these devices and, at the same time, to have the optics and fluidics parts integrate in the same device, the 3D Printing technology based on the Poly(dimethyl-siloxane) (PDMS) is proposed. All these aspects were addressed considering the two-phase flow (named slug) generated by the interaction of two immiscible fluids, a very common condition in bio-chemical applications. The methodological aspects were discussed in the first part of the thesis, starting from the extraction of parameters for the flow characterization, to their use for the flows real-time modelling and control schemes development; the second part investigates aspects faced for the realization of micro-optical flow detector by using the 3D Printing technology.

circSMARCA5-SRSF1 interaction is functionally involved in GBM pathogenesis

Glioblastoma multiforme (GBM) is the most aggressive human brain tumor with a median survival of 15 months. The standard treatments of GBM and the total medical resection are unable to contrast this mortal cancer. For these reason new diagnostic approaches and therapies are needed. The identification of molecular features of this cancer may allow to create a personalized therapy. Circular RNAs (circRNAs) are a new class of non-coding RNAs (ncRNAs) highly enriched in brain, stable within the cells, detectable in body fluids and having a potential role and biological importance still object of debate. This thesis investigated the putative involvement of circRNAs in GBM pathogenesis. It has been demonstrated that circSMARCA5 is downregulated in GBM biopsies, its expression is associated to the glioma grade malignancy and it negatively regulates migration of U87MG cells. Moreover, it has been proved the physical interaction between circSMARCA5 and one of its predicted interactor Serine/arginine-rich splicing factor 1 (SRSF1). Interesting splicing targets of SRSF1 are the serine and arginine rich splicing factor 3 (SRSF3) and the vascular endothelial growth factor A (VEGFA). It has been proposed that circSMARCA5 may regulate the alternative splicing of SRSF3 in favor of the formation of a stable oncoprotein in GBM. It also regulates the alternative splicing of VEGFA mRNA through the binding to SRSF1. In addition, blood vascular microvessel density evaluated in GBM negatively correlates with the expression of circSMARCA5, while positively correlates with that of SRSF1 and pro-to-anti-angiogenic VEGFA isoform ratio. GBM patients with low circSMARCA5 expression have lower overall and progression free survival rates. Based on these findings, CircSMARCA5 could be considered a promising druggable tumor suppressor in GBM. Moreover, its interaction with SRSF1 makes circSMARCA5 an upstream regulator of pro- to anti-angiogenic VEGFA isoforms ratio within GBM cells and a highly promising GBM prospective anti-angiogenic molecule.

Se il cavaliere Gioeni avesse riletto Linneo e Dezallier d’Argenville

Ultimamente si è accumulato un certo numero di articoli divulgativi e citazioni di letteratura che riferiscono il giudizio del matematico Charles Babbage sulla frode scientifica del cavaliere Giuseppe Gioeni nel 1783. Un articolo recente (2021) e un passo di una biografia celebrativa (1842) del personaggio hanno tentato di riabilitare un naturalista presunto fraudolento per la scoperta di una nuova specie di mollusco rinvenuto sul litorale di Catania, già nota come Scaphander lignarus o Bulla lignaria di Linneo. È presentata una rassegna di commenti demolitivi in proposito. Nelle vicissitudini culturali e nelle traversie della vita pubblica e privata di Gioeni può trovarsi l’origine di un errore scientifico mai riconosciuto dall’autore, così come appare nei documenti di archivio oggi noti. Inoltre sono riportati un altro non riconosciuto errore malacologico a carico del chimico Carmelo Maravigna e alcune approvazioni sulla tassonomia ottocentesca adottata dallo zoologo Andrea Aradas a riguardo di nuovi molluschi siciliani.

Flora marina bentonica del Mediterraneo: Rhodophyta - Rhodymeniophycidae II. Halymeniales, Nemastomatales, Peysson-neliales, Plocamiales, Rhodymeniales, Sebdeniales

Dopo una breve introduzione sui 6 Ordini che costituiscono l’oggetto di questo secondo contributo alle Rhodymeniophycidae del Mediterraneo (Mar Nero escluso), si passa alla trattazione dei taxa seguendo l’ordine strettamente alfabetico.La trattazione riguarda 131 taxa correntemente accettati, di cui 126 a livello specifico e infraspecifico e 5 a livello solamente di genere. Inoltre vengono censiti 132 taxa (a livello specifico e infraspecifico) non accettati, nonché altri 280 taxa (a livello specifico e infraspecifico) sinonimi dei taxa accettati e/o non accettati. Dei 124 taxa a livello specifico e infraspecifico accettati, 96 sono componenti tradizionali della flora macroalgale mediterranea, 12 sono alieni o involontariamente introdotti, 16 sono taxa excludenda. Tutti i taxa accettati sono ripartiti in 39 generi di cui: 31 con rappresentanti in Mediterraneo, 3 sono excludenda, e 5 privi di rappresentanti in Mediterraneo (solamente citati nel testo). I 132 taxa non accettati sono così ripartiti: 47 sono taxa inquirenda (di cui 3 con nome illegittimo); 32 sono taxa con nome illegittimo (3 dei quali sono anche taxa inquirenda); 41 sono taxa con il nome invalidamente pubblicato (32 dei quali sono nomina nuda); 15 taxa sono combinazioni invalide. Di ciascun taxon trattato viene fornita una breve descrizione preceduta da alcuni riferimenti bibliografici riportanti notizie, illustrazioni e/o distribuzione in Mediterraneo. La trattazione della maggior parte dei taxa specifici e infraspecifici è corredata da tavole iconografiche; inoltre, quasi tutti i taxa trattati sono arricchiti di note bilingue (Italiano e Inglese) a supporto delle sinonimie indicate, o delle scelte tassonomiche seguite o delle motivazioni per cui il taxon è stato considerato inquirendum e/o excludendum o delle conclusioni nomenclaturali. Inoltre, vengono proposte 3 nuove combinazioni, 2 delle quali di taxa non presenti in Mediterraneo. Il lavoro è completato da un glossario di 173 voci, da un indice di tutti i nomi dei taxa citati nel testo e da una errata corrige al precedente lavoro sulle Rhodymeniophycidae di Cormaci et al. (2020).

Resonance

In this contribution, the theme of resonance is dealt with. Considering the fundamental role of resonance and its universality in more topics, a guided route about resonance is discussed. Moreover, the universal concept of resonance is stressed and enlarged to a system generalization, both in social sciences and arts.

L'Accademia Gioenia al tempo della "Spagnola"

Si riporta un esame critico dell'attenzione rivolta alla "Spanish flu" o influenza spagnola, comparsa all'inizio del XX secolo come malattia letale, ad opera di soci dell'Academia Gioenia di Catania. La grande pandemia d'infezione polmonare, secondo gli studiosi, fu definita come "uno dei più grandi nemici dell'uomo". Tuttavia, le caratteristiche della ricorrente pandemia che colpì la maggioranza della popolazione della Sicilia nell'autunno del 1918, l'agente eziologico, le misure sociali e i rimedi sanitari approntati al suo esordio sono stati sorprendentemente poco esaminati e discussi in adunanze accademiche e anche nelle pubblicazioni apparse nelle due riviste edite dall'Accademia.

Allelopathic effects of Cynara cardunculus L. extracts

Weeds are recognized as the most important biotic factor affecting yields in agroecosystems. The negative effects derived from the irrational use of herbicides have led to an increasing interest to eco-friendly practices for weed control, including the manipulation of allelopathic mechanisms. The present study aims to explore the potential use of Cynara cardunculus L. leaf extracts for the biological control of weeds and pathogen microorganisms. In a first trial, the allelopathic effects of its leaf aqueous extracts were demonstrated on seed germination of six common weeds. Secondly, the set-up of the most efficient extraction method of its allelochemicals in terms of costs, yields and inhibitory activity was realized, selecting dried leaves as the best plant material and ethanol and ethyl acetate as the best solvents. Moreover, new C. cardunculus allelochemicals (cynaratriol, desacylcynaropicrin, 11,13-dihydro-desacylcynaropicrin and pinoresinol) were purified. Third, the effect of genotype, harvest time and light stress (by plant shading) was evaluated on the phytotoxicity, quantity and composition of sesquiterpene lactones in C. cardunculus leaf extracts through a new UHPLC-MS/MS analysis method. Wild and cultivated cardoon showed the highest concentrations, while spring was the best harvest time. Moreover, light stress stimulated the synthesis of these allelochemicals. In a second trial, the effects resulting from 3-years cultivation, in two different areas, with globe artichoke, cultivated and wild cardoon were studied on the quali/quantitative composition of the weed soil seed bank and on soil eubacterial communities. In both areas, C. cardunculus reduced the weed seed bank size compared to controls. Nevertheless, the presence of cultivated cardoon had a negative influence towards Bacillus subtilis and a positive one on Pseudomonas putida and Azospirillum brasilense. Lastly, cultivated cardoon leaf extracts were assessed in vitro for the control of several microorganisms of agriculture and food interest. All the extracts showed an important antimicrobial activity, especially when using ethanol as extracting solvent.

A public participatory GIS and multi criteria decision analysis framework for the evaluation of transport scenarios

The decision-making process of transport projects is very complex, especially for public administrations which have to take into account often incomparable criteria of judgment. In addition, in order to achieve a good social sharing and robustness of the decision, policy makers have to include in the process not only the transport planning experts but also the stakeholders of the community. The purpose of this study is to propose an evaluation framework to support the decision making process, able to allow public participation in the assessment of transport planning and design scenarios while, at the same time, ensuring a high level of technical quality of the final decision. The designed framework includes a method to analyze monetary and non-monetary parameters, easily understandable for all decision makers. It is based on the application of Multi Criteria Decision Analysis (MCDA) techniques, an evaluation process that can take into account different quantitative and qualitative objectives and criteria; in order to favor public participation, the implementation of this technique takes advantage of Geographic Information System (GIS) for its ability to easily represent the impact of spatially based alternative project scenarios. The analysis of several case studies on transport planning and design scenarios allowed to assess the level of implementation of the three main ingredients of the framework: MCDA, GIS and public participation.

DNA methylation and retinal degenerative diseases: at the crossroad between genes and diet

Retinal degenerative diseases are the leading causes of blindness and low vision among working-age and older adults worldwide, with 170 and 130 million individuals suffering from age-related macular degeneration (AMD) and diabetic retinopathy, respectively. Although several studies began to show benefits from dietary interventions against retinal degenerative disease, an integrated approach is needed to understand molecular mechanisms underpinning the protective or risky effect of dietary factors. A specific area of research that elucidates mechanisms involved in gene-diet interaction is the Nutri-epigenomics, the study of the impact of diet on gene expression by modulating epigenetic mechanisms. The present research investigated the role of DNA methylation – one of the most commonly analysed epigenetic mechanisms - in the pathophysiology of retinal degenerative diseases, by exploiting a multiple integrated approach. In vitro studies initially helped us to understand how pathological features of retinal degeneration (e.g. oxidative stress, inflammation and hyperglycaemia) modulated functions of enzymes involved in the methylation of Long Interspersed Nuclear Element 1 (LINE-1) sequences in retinal cells. We also proved that some nutrients (e.g. resveratrol and curcumin) might counteract these effects and restore DNA methylation level in retinal cells under oxidative, inflammatory and high glucose conditions. We further analysed whether LINE-1 methylation level differed between patients with AMD and controls without posterior segment eye diseases. Interestingly, we noted a significant difference between the two groups, with higher LINE-1 methylation level in blood samples from AMD patients. This evidence -albeit promising for biomarker discovery- requires confirmation by further large-size prospective studies taking into account different factors. Our research, in fact, also suggested that the risk of retinal degenerative diseases derives from the combination of genetic risk variants, clinical characteristics, environmental exposures and unhealthy lifestyles, which in turn are interrelated. Thus, it would be interesting to study how the exposome -the totality of exposures individuals experience over the course of life- might induce epigenetic mechanisms able to reduce or increase the risk for retinal degenerative diseases.

La pandemia da Covid-19: un provvidenziale avviso dalla Natura

Stiamo viaggiando nell’infinità dell'Universo sul pianeta Terra, un'astronave con 7,8 miliardi di passeggeri che non potrà mai "atterrare" da nessuna parte e neppure fermarsi in qualche luogo per caricare risorse o scaricare rifiuti. Le risorse su cui noi passeggeri possiamo contare sono i materiali che compongono l'astronave e la luce del sole. Qualsiasi danno all’astronave deve essere riparato e qualsiasi problema deve essere risolto da noi passeggeri. Gli scienziati avvertono da molti anni che non stiamo custodendo il pianeta e i sociologi ammoniscono che le enormi disparità economiche e sociali stanno diventando insostenibili. Da alcuni mesi, un virus pericoloso e altamente contagioso, Covid-19, sta circolando sull'astronave Terra. Dovremmo prenderlo come un avvertimento da parte della Natura per avviarci verso la sostenibilità ecologica e sociale.