3284 research outputs found
Sort by
Oxidative stress in severe asthma smokers
No full textBackground
As part of the U-BIOPRED project, extensive clinical and biomarker information was collected from cohorts of adult severe asthma smokers/ex-smokers (SAs/ex) and severe asthmatic non-smokers (SAn). Oxidative stress in SAs/ex vs SAn patients was investigated by analysing urinary 8-iso-PGF2a and the mRNA expression of the main pro-oxidant (NOX2; NOSs) and anti-oxidant (SODs; CAT; GPX1) enzymes in the airways, in relation to clinical outcomes.
Methods
Urine and induced sputum (IS) were obtained from severe asthma patients. A bronchoscopy to obtain bronchial biopsy (BB) and brushing (BBr) was performed in a subset of patients. Urinary 8-iso-PGF2a was quantified using mass spectrometry. IS, BB and BBr were processed for mRNA expression microarray analysis.
Results
Urinary 8-iso-PGF2a was increased in SAs/ex compared to SAn (p< 0.001) and in current smokers vs ex-smokers and non-smokers (p= 0.004). Sputum mRNA expression of NOX2 were increased in SAs/ex compared to SAn (three probe-sets with p< 0.05). The mRNA expression of antioxidant enzymes was similar between the two severe asthma cohorts in all airway samples. NOS2 mRNA expression was decreased in BBr of SAs/ex compared to SAn (p= 0.029). NOS2 mRNA expression in BBr correlated with FeNO (p< 0.001). FeNO was lower in current-smokers than in ex-smokers (p= 0.007) indicating an effect of active smoking.
Conclusions
The data suggests evidence of greater systemic oxidative stress in SAs/ex with significant effects on the mRNA expression of NOX2 and NOS2 in the airways of severe asthmatic patients
Strategic alliances: value creation and appropriation mechanisms, configuration, and portfolio evolution
No full textThe object of this dissertation is to provide a better understanding of strategic alliances with a specific focus on value creation and value appropriation mechanisms, alliance configuration, and the evolution of alliance portfolios. In more detail, the purpose of the dissertation is threefold:
(I) to summarize the existing alliance research around value creation and value appropriation processes, which are the two distinct, dynamic and interrelated processes underlying alliance partners performance. In doing so, it aims to shed lights on the theoretical underpinnings that explain the key value creation and value appropriation mechanisms that lie beneath the two processes. In addition, it aims to clarify the interdependence between the two processes, thereby advancing a contribution that conceptually tackles the need to treat value creation and value appropriation jointly (e.g., Di Minin and Faems, 2013; Lepak et al., 2007);
(II) to rejoin the challenge to explore the relationship between R&D alliances and alliance partners innovation performance, by relying on the theoretical lens of the knowledge-based view of the alliances (Grant & Baden-Fuller, 2004; Vasudeva & Anand, 2011). Specifically, by adopting this theoretical lens we challenge the issue to identify the major factors that lead alliance partners to achieve high innovation performance by means of R&D alliances. Additionally, a challenge of the research is to revamp a key research stream in the alliance literature (i.e., alliance configuration) by examining the combinatory effects that inevitably occur among these factors;
(III) to explore the features that epitomize alliance strategy with regards to the management of alliance portfolio. In particular, the dissertation aims to undertake an investigation of the existing body of research on alliance portfolio management in order to elucidate its main features. In addition, the dissertation is aiming to complement extant research with an investigation of these features in a case study (Ericsson) in order to provide insights on alliance strategy, from the managerial point of view (Hoffman, 2005)
Spectropolarimetric techniques and applications to stellar magnetism
No full textThis dissertation is aimed at the measurement and the characterization of stellar magnetic fields,
which are one of the most challenging topics in the modern astrophysics.
They are been detected in almost
all the stellar evolutionary stages, from pre-main sequence to degenerate stars. They are the keys from the understanding of several phenomena, such as accretion on pre-main sequence stars, stellar activity and spots and they are also important in order to investigate possible false detections of exoplanets and to characterize star-planet interactions.
In particular, this thesis focus on the study of upper main sequence, active solar analogs and stars hosting planet, with particular attention on evolved stars.
Stellar magnetic fields can be measured through the polarization and the splitting due to Zeeman effects, from spectropolarimetric observations.
In particular, this dissertation employs archive data of Narval and HARPSpol and it is based on observations obtained with the instruments CAOS (Catania Astrophysical Observatory Spectropolarimeter) in more than hundred nights, during the period of the thesis.
Full Stokes observations of the magnetic Ap star BetaCrB are used in order to determine the transversal component and the angle of the magnetic fields.
The observations of a sample of 22 stars with detected planets are used in order to study the impact of the presence of the field; results show that the 47% of the giants and the 40% of the main
sequence stars in the sample host magnetic fields. In particular, the field strengths of the giant stars show a correlation with the rotational period, which can be connected to the presence of a dynamo process driven by rotation.
Measurements are performed through the Least Square Deconvolution technique, using a code that was implemented and tested during the period of thesis.
Furthermore, a new technique for the measurement of the effective magnetic field from high-resolution observations is introduced. This technique, called multi-line slope method, is tested with synthetic spectra and it is applied to a dataset of spectropolarimetric observations of the active star EpsEri, which spans 9 years from 2007 to 2016.
The temporal analysis allows to determine a period of variation (P1=1099±71d) consistent with the variation of the activity index. This measurement represents the first estimation of the period of the cycle of a star obtained from direct measurements of the magnetic field
SUSTAINABLE DEVELOPMENT OF REGIONAL BIOGAS PRODUCTION: Gis-based Techno Economic Assessment In Southern Italy
No full textRenewable energies have attracted increasing attention in the past decades due to the need to reduce consumption of energy from fossil fuels and GHG emissions. In this respect, energy production from agri-food biomass has been researched and developed regarding both processes and biomass feedstocks (food crops, non-food crops, and by-products and residues). Recently, an innovative system based on both intensification of crop rotation and use of by-products was derived from BIOGASDONERIGHT concept, which aims to sustainably make more biogas. Therefore, the main objective of this thesis was to apply advanced GIS modeling and biomethane potential test to investigate availability of byproducts and wastes, and conclude suitable biogas production system in the region of Sicily.
A hypothetical regional biogas power generation system based on multiple biomass feedstocks for the Catania province in Sicily was developed using GIS modeling tools, and evaluated by techno-economic assessment and economic sensitivity analysis. The analysis of availability and distribution of the multiple biomass feedstocks identified the best locations of four biogas plants in terms of optimization of biomass logistics. The size and location of four biogas plants in the system were determined by buffer zone and road network analyses. Moreover, the effects of mixing six feedstocks (citrus pulp, olive pomace, cattle manure, poultry litter, whey, and corn silage) on anaerobic digestion of biogas production have been investigated by this study using a combined biomethane potential (BMP) and semi-continuous anaerobic digestion (AD) testing approach, in order to maximise the biogas production. The system demonstrates excellent economic performance with a payback period of less than three years for all four biogas plants. The economic sensitivity analysis clearly presents that, after establishment of the regional biogas plants according to feedstock availability and transportation, some customised adjustments on operations at local level could be carried out to further improve the economic performance of individual biogas plants. The system offers a sustainable solution for renewable electricity generation and soil amendment production from agricultural residues and food wastes in the region of Sicily
The design of a network of energy distribution among prosumers
No full textSince cities are responsible for the 67% of the world s energy demand and are the major contributors of CO2 emissions, governments and researchers push towards energy policy initiatives aiming at increasing the sustainability of urban areas. In this context, the diffusion of autonomous energy production systems on territory has been recognized as a cost-effective solution; moreover, their integration gives to consumers the possibility to exchange their own produced energy. This permits to configure a network of energy interactions among prosumers , i.e. consumers with production capabilities. In order to design the optimal energy distribution network among prosumers and, the same time, minimize the energy supply from traditional power plants, a comprehensive and focused approach is introduced and developed in this paper. The presented model encompasses the frameworks of both complex networks theory and agent-based models to provide a suitable solution of the energy distribution problem. The study is conducted for static and dynamical scenarios and the theoretical simulations are then compared to a real case study.
Overall, the proposed model offers significant insights for the definition of proper urban action plans centered on the efficient usage of energy and favouring the exploitation of renewable energy, thus allowing urban planners to make reasoned investment decisions
SIRENE un linguaggio di programmazione visuale per la didattica della programmazione
No full textDalla metà del ventesimo secolo vi è stato un aumento della diffusione dei personal computer dovuto ad una crescente domanda nel mercato di questo elaboratore grazie alla sua riduzione sia di prezzo e sia di dimensioni. Questo ha permesso, a molte persone, di poter utilizzare i computer per le più svariate finalità e non soltanto per attività di tipo strettamente scientifico o accademico. La facilità di utilizzo, dovuta alle interfacce Uomo-Macchina, e le potenzialità di utilizzo dei personal computer hanno portato le comunità scolastiche ed accademiche, nazionali ed internazionali, a sviluppare corsi di programmazione a ogni livello. In questi anni, dunque, sono stati sviluppati molti strumenti utili all implementazione di programmi: molti di questi usano un paradigma text-based mentre solo pochi strumenti usano un paradigma visuale, o iconico. Questo lavoro propone un framework iconico di programmazione utile all insegnamento ed all apprendimento dell arte della programmazione, a livello sia concettuale e sia implementativo, in un contesto collaborativo e distribuito in rete sfruttando le più recenti tecnologie per una condivisione, in tempo reale, dell ambiente di lavoro e degli algoritmi e programmi sviluppati tra il docente, o l esperto , e gli studenti, o i principianti . Si discuterà delle difficoltà comuni che hanno gli studenti dei corsi di programmazione e lo stato dell arte attuale degli strumenti iconici di sviluppo utili all insegnamento e all apprendimento della programmazione. Dunque, si presenterà un framework iconico, SIRENE, che possiede caratteristiche real-time, è cooperativo, usabile in ogni dispositivo ed in internet ed è progettato per l insegnamento e l apprendimento della programmazione. Si discuterà della sua implementazione, argomentando anche delle varie difficoltà implementative riscontrate e le loro soluzioni. Si perverrà, infine, alla conclusione analizzando una sperimentazione ed i suoi risultati e la realizzazione del framework visuale, dei suoi possibili usi pratici, delle sue potenzialità e delle sue possibili estensioni
Il volto "poliedrico" dell'ente nel modello processuale ex d.lgs. n. 231/2001
No full textLa ricerca mira ad esaminare il ruolo attualmente ricoperto dalle persone giuridiche in seno al procedimento penale a seguito dell'entrata in vigore del d.lgs. n. 231 /2001. La normativa citata ha, infatti, introdotto una nuova ipotesi di responsabilità per la societas, la cui natura è ancora piuttosto dibattuta, e che - sebbene sia formalmente qualificata come amministrativa -cela in realtà un volto sostanzialmente penale. Alla luce della riforma introdotta nel 2001, sul piano processuale si è assistito ad una vera e propria rivoluzione copernicana, atteso che le persone giuridiche - in precedenza chiamate a rivestire il ruolo di meri soggetti eventuali del procedimento - sono ora chiamate ad assumere una posizione assimilabile a quella dell'imputato, venendo quindi in considerazione nell'inedito ruolo di soggetti necessari. L'arduo compito del legislatore è, dunque, coinciso con la necessità di adeguare alla partecipazione di questi nuovi "ingombranti soggetti" le strutture processuali preesistenti e costruite intorno alla figura di imputato-persona fisica, con non poche frizioni in ordine all'osservanza di principi fondamentali quali il diritto di difesa e la tutela risarcitoria della vittima del reato
Sociality in Complex Networks
No full textThe study of network theory is nothing new, as we may find the first example of a proof of network theory back in the 18th century. However, in recent times, many researchers are using their time to investigate networks, giving new life to an old topic. As we are living in the era of information, networks are everywhere, and their complexity is constantly rising. The field of complex networks attempts to address this complexity with innovative solutions. Complex networks all share a series of common topological features, which revolve around the relationship between nodes, where relationship is intended in the most abstract possible way. Nonetheless, it is important to study these relationships because they can be exploited in several scenarios, like web page searching, recommender systems, e-commerce and so on. This thesis presents studies of sociality in complex networks, ranging from the microscale, which focuses the attention on the point of view of single nodes, to the mesoscale, instead shifts the interest in node groups
A sustainable organic production model for Food Security in Abu Dhabi Emirate and Sicily
No full textThe research aims to analyze the link between sustainability
and food security, in two study areas - the United Arab
Emirates and Sicily - characterized by numerous elements of
similarity (from the climatic point of view, in the availability
for quality and quantity of water resources; widespread
sensitivity in adopting organic or sustainable methods of
cultivation, high demographic immigration, of a politicaleconomic
and tourist nature, with repercussions in the
organization of the socio-cultural, territorial working system,
etc.) and of diversity (in average incomes per capita, in the
availability of financial resources for investments, etc.).
This link has been studied through organic farming which, as
we know, is a possible solution for both problems, both in
advanced and developing countries. In fact, the food security
of any territory is not simply linked to the ability to produce
enough food to satisfy domestic demand, but also to the
possibility of having access to technology and knowledge to
produce it on the territory, to the purchasing power, etc.
From this point of view, the literature demonstrates how the
success of organic farming is based on five capital goods
(natural, social, human, physical and financial capital),
producing a variety of positive externalities (in the
availability of food through the regeneration of the substance
organic land, in contrast to soil erosion and biodiversity
protection, in the creation of increasingly large number of
local social organizations, new rules and rules for the
management of collective natural resources, in the ability and
ability of farmers to experiment and solve various problems,
in support of marginalized groups or low-level contracts, in
the best health and nutrition of children, in price premiums for certified organic products, etc.). For these premises,
organic farming makes it possible to implement sustainable
food systems, capable of ensuring the food security of a
territory and, consequently, the conservation and cultural
reproduction of the indigenous knowledge characteristic of
the concept of "food sovereignty".
The drafting of the text proceeds in coordinated parts. After
defining the concept of sustainability in the modern agri-food
system, we have analyzed the characteristics of the areas
under study, the level of food safety, the state of agriculture
and the spread of organic agriculture, according to the most
accredited international statistical sources. . We then
proceeded to examine the sustainability of the two territorial
production systems under study, using the SAFA
(Sustainablility Assessment of Food and Agriculture Systems)
methodology of the FAO and the consequences on local food
security and sovereignty. Subsequently, through the use of
Social Network Analysis (SNA) methodologies,
relationships were studied in the link between production,
distribution and consumption with the aim of assessing the
ability of companies to communicate sustainability values to
potential buyers. Finally, the behavior of a sample of
consumers was analyzed with the aim of analyzing behavior
and preferences, in the awareness of the role that this actor
plays within the agri-food system
Archeologia dei paesaggi rurali della Piana di Catania
No full textLa tesi espone i risultati del progetto di ricerca condotto sui paesaggi rurali della Sicilia orientale, attraverso il caso studio offerto dai margini occidentali della Piana di Catania. Il progetto è scaturito dai risultati delle ricognizioni condotte tra il 1997 e il 2007 nelle valli dei fiumi Simeto, Dittaino e Margi, ai fini della redazione della carta archeologica del territorio delle Tavolette IGM F. 269 II NO Monte Turcisi, F. 269 III SE Ramacca, F. 269 III NE Castel di Iudica e F. 269 III SO La Callura. I nuovi dati sono relativi a numerose aree di frammenti (131) pertinenti a fasi di occupazione che vanno dalla Preistoria al Medioevo: ai fini della piena comprensione delle dinamiche dell insediamento e della viabilità nell area, i dati sono stati messi in relazione alle informazioni note in letteratura e ai risultati delle ricerche di archivio condotte presso le Soprintendenze di Catania e Siracusa, l Ufficio Tecnico Speciale per le trazzere e l Ente per la Bonifica della Piana di Catania.
Il paesaggio rurale della Sicilia sud-orientale non è tra i più intensamente studiati nel contesto del Mediterraneo. Tuttavia, la quantità di legacy data disponibili per la Sicilia può contribuire a colmare questa lacuna. Al fine di raggiungere una chiara comprensione dei processi tafonomici che hanno modellato i paesaggi siciliani dell entroterra, si è tentato di dare una nuova lettura dei dati archeologici noti alla luce dei risultati delle ricognizioni intensive condotte ai margini della Piana di Catania e della ricerca storica. Quindi, attraverso l'analisi della cartografia e della fotografia aerea storica, è stato possibile mettere insieme in un quadro organico le tracce dei paesaggi rurali antichi, strettamente correlati alle dinamiche dell'insediamento e della viabilità. Sia la natura geomorfologica dell'area di studio che la posizione a cavallo tra la costa ionica e il versante meridionale dell'isola hanno chiaramente influenzato le traiettorie dello sviluppo economico locale e, quindi, anche le dinamiche insediative. I risultati ottenuti attraverso l elaborazione dei dati nel geo-database Ru.NS forniscono, quindi, un'immagine vivida sulle linee di sviluppo dei sistemi insediativi di questa porzione della Sicilia sud-orientale in antico, tracciando, nella lunga durata, gli elementi di continuità e di discontinuità nella distribuzione degli insediamenti nel territorio dal Paleolitico all Alto Medioevo