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Genetic and phylogenetic characterization of microalgae strains in view of their exploitation for CO2 capture and biofuel production
Get PDFIn the light of for sustainable development, microalgal biodiesel, as a renewable and sustainable
energy type, has enjoyed a surge in popularity. In fact, differently from the first generation biofuels,
the use of microalgae to produce bioenergy does not involve the triggering of "food for fuel"
competitivity and thus represents a sustainable mean to face significant concerns, such as wars and
political instabilities deriving from oil reserves shortage. Morevoer, the high oil yields and less land
use are the main advantages of microalgae. However, in order to make the current technology
viable at the large-scale, several limitations should be overcome. In particular, biomass and lipid
productivities should be further increased and all the downstream processes, from harvesting to
lipid extraction, should be optimized. To these aims, high efforts involving high investments should
be done in order to implement an intensive multidisciplinary research activity both at the laboratory
and the industrial scale.
The microalgae cultivation is the base of biofuel development and suitable genetic engineering
strategies have to be developed in order to augment the microalgae oil content and their growth rate
so that biofuels production could performed in a sustainable way. In particular, the creation of new
microalgal strains intrinsically characterized by high lipid productivities as well as by a good
tolerance to high CO2 levels is an ambitious goal which might be achieved only once their genome
is known. The results presented in this thesis represent the first step needed to design a genetic
approache which may eventually facilitate large-scale production of algae. The use of transgenic
microalgae for the production of bioproducts represent an enormous economic and biotechnology
promise, because algal production combines the simplicity and speed of haploid, single-cell
genetics in an organism with elaborate biosynthetic potential, and with the associated economic
benefit of using photosynthesis to drive product formation.
As technology continues to be progressed and algae production industrialization continues to be
improved, microalgae energy as the third generation biofuel will contribute their own strength to
relieve the tense situation of resources.
The contribution of the present work, to this general target can be briefly summarized as follows.
The growth kinetics of C. sorokiniana has been investigated along with their corresponding lipid
content, both batch and helical photobioreactors. The main results achieved during this activity are
the knowledge of the effect of nitrogen concentration in solution on the growth rate and lipid
content of C. sorokiniana. These informations represent the first step towards the development of a
nitrogen based strategy for the optimization of lipid productivity of C. sorokiniana cultures.
As far as the genetic characterization activity, the chloroplast and mitochondrial DNAs of two
strains, i.e. C. sorokiniana and C. variabilis, respectively, have been sequenced for the first time in
the literature. The obtained results allowed to perform a phylogenetic assessment involving
different microalgae strains belonging to the Chlorella clade. Such results represent the first
important step towards the development of genetic engineering strategies aimed to improve the
current microalgae based systems for the production of biofuels and the capture of CO2
Caratterizzazione proteomica di fluidi e tessuti in diverse condizioni fisio-patologiche
Get PDFThis thesis has been focused on the proteomic characterization of human saliva
from donors of different ages, starting from birth up to adult age, and pediatric
brain tumor tissues. The first study has been performed in order to compare the
acid-insoluble fraction of saliva from preterm with at-term newborns and adults and
establish if differences exist. In the second study medulloblastoma and pilocytic
astrocytoma pediatric brain tumor extracts have been compared. In both studies 2-
DE analysis was coupled with high resolution tandem mass spectrometry (MS/MS).
The proteomic characterization of the acid-insoluble fractions of saliva from
preterm newborns allowed to integrate data previously obtained on the acid-soluble
fraction by HPLC-electrospray ionization (ESI)-mass spectrometry (MS), and to
evidence several differences between preterm newborns, at-term newborns and
adults.
Spots differentially expressed between the three groups, according to image
analysis of the gels, were submitted to in-gel tryptic digestion and the peptide
mixture analyzed by high performance HPLC-ESI-MS/MS for their
characterization. By this strategy, we identified three over-expressed proteins in atterm
newborns with respect to preterm newborns and adults (BPI fold-containing
family A member 1, two proteoforms of annexin A1, and keratin type 1
cytoskeletal 13), and several over-expressed proteins in adults (fatty acid-binding
protein, S100A6, S100A7, two proteoforms of S100A9, several proteoforms of
prolactin-inducible protein, Ig kappa chain, two proteoforms of cystatin SN, one
proteoform of cystatin S and several proteoforms of α-amylase 1). Moreover, for
the first time, it was possible to assign by MS/MS four spots of human saliva 2-DE,
already detected by other authors, to different proteoforms of S100A9. The strategy
applied used a sequential staining protocol to the 2-DE gels, first with Pro-Q
Diamond, that allows specific detection of phosphoproteins, and successively with
total protein SYPRO Ruby stain.
In the second study, proteomic analysis of two pediatric brain tumor tissues pointed
out differences between medulloblastoma, the prevalent malignant tumor in
childhood, and pilocytic astrocytoma, the most common, that only rarely shows a
malignant progression. Due to the limited availability of bioptic tissue, the study
was performed on pooled tumor tissues, and was focused on acid-insoluble fraction
to integrate the characterization performed by a group of colleagues in Rome on the
acid-soluble fraction by high performance HPLC-ESI-MS/MS. The results indicated that the two tumors exhibit different proteomic profiles and evidenced
interesting differential expression of several proteins. Among them, peroxiredoxin-
1, peptidyl-prolyl cis–trans isomerase A, heterogeneous nuclear ribonucleoproteins
A2/B1, mitochondrial isoform of malate dehydrogenase, nucleoside diphosphate
kinase A, glutathione S-transferase P and fructose bisphosphate aldolase A resulted
significantly over-expressed in medulloblastoma while glial fibrillary acidic
protein, serotransferrin, α crystallin B chain, ferritin light chain, annexin A5, fatty
acid-binding protein (brain), sorcin and apolipoprotein A-I resulted significantly
over-expressed in pilocytic astrocytoma.
In conclusion, the work done allowed to evidence the usefulness of using an
integrated bottom-up/top-down approach, based on 2-DE-MS analysis and high
performance MS in order to obtain a complete characterization of the proteome
under investigation, revealing and identifying, not only peptides and small proteins,
but also proteins with higher MW, that often it is not possible to identify by using
exclusively a top-down ESI-MS approach
Rete simbolica e dinamiche della memoria nella trilogia della guerra civile di Juan Eduardo Zúñiga
Get PDFThe aim of this PhD thesis is to explore Juan Eduardo Zúñiga’s private and literary path
in order to illustrate the author’s intellectual complexity and especially to offer a critical
analysis of the most significant part of his production, that is the so called “trilogy of the
Spanish Civil War”, which includes the short stories of Largo noviembre de Madrid
(1980), La tierra será un paraíso (1989) and Capital de la gloria (2003). Zúñiga
(Madrid, 1919) is among the most distinguished Spanish contemporary writers but his
work hasn’t been investigated at a profound level yet. The research aims to turn this
initial disadvantage into a challenge, demonstrating how the author’s personal evolution
intertwines with the historical context of the Spanish Civil War firstly and the Francoist
regime secondly through a constant dialog with this period, especially when he recovers
and saves from the oblivion the multiple voices of the Madrilenian intrahistoria, the
real protagonist of the historical changes.
Therefore the trilogy, which is almost an unexplored land, is at the core of the research.
After a brief but necessary recap of the most relevant events of contemporary Spain and
also Zúñiga’s biographical reconstruction (developed in the first part of the thesis), the
study will focus later on two narrative aspects that define and identify the cycle (in the
second part). Symbolism and Memory, effectively, permeate the trilogy due to their
repetition and interconnection, making the whole organic, systematic and cohesive. The
textus comes up as a real net, a bundle made of recurring “objects-symbol”, characters
and themes. It is also a lieu de mémoire where the construction and the destruction of
memories and identities (both individual and collective) are widespread narrative
operations that show the historical Spanish society opposition between vencedores (the
Nationalists) and vencidos (the Republicans).
Specific short stories from the three volumes have been selected in order to illustrate
and examine how symbols work and also how the dynamics of memory and oblivion
structure the diegesis. The result is a complex panorama made of tradition and
innovation created by Zúñiga to give testimony of the controversial age that he lived, as
citizen and historical witness, in order to transmit and preserve the historical memory
(memoria histórica) of the Spanish Civil War
I nuovi strumenti di finanziamento per le PMI: una possibile applicazione alle imprese sarde
Get PDFThe financial crisis has highlighted the structural weakness of Italian firms, highly bank-dependent and characterized by high leverage as well. The proposed solutions to finance and favour the recovery – promoting the direct access of firms to the financial market – are theoretically robust and acknowledged by the financial literature – although difficultly implementable due to an Italian financial market not adequately developed.
Apart from the aforementioned issues, this study presents a detailed empirical analysis on the dynamics of the Minibond-market (two years after its launch) and analysis – through the employment of “early warning” models based on a sample of 1.225 firms – the endogenous features (linked to the financial structures of the issuing firms) that have influenced firms about the choice of issuing, or not, the Minibonds
Nullità e inesistenza del provvedimento amministrativo: profili statici e dinamici del rapporto alla luce del nuovo codice del processo
Get PDFAt the beginning, the research was intended to be developed in two stages. In the first stage I had to analyze the difference between invalid and non-existent case from a general perspective.
With this goal in mind, I began this study and research analyzing the most reliable contribution of civil law. The initial approach, profoundly linked to civil law, was, in my opinion, necessary due to two reasons: the first reason is the versatility of the subject that has its roots in civil law; the second reason is the need to highlight the peculiarity of the administrative decision in comparison with the legal transaction, in order to deny the opportunity to fill any regulatory gaps merely through a reference to the categories of private law .
In a second stage, I had to analyze the profiles more closely related to protection, or, to better say, to the impact that the distinction between invalidity and non-existence would have determined on the protection of subjective legal claims affected by the measure, invalid and non-existent. However, analyzing in detail the relationship between the two figures , first from a logical – legal point of view , and later from a practical point of view , especially with reference to the recent positive outcome, I realized that the approach initially undertaken regarding the administrative measure, would no longer be effective. Developing my research and approaching the topic from a public law perspective, I realized that the debate was gradually taking different characteristics that didn’t allow to face the issues splitting the two perspectives (first addressing them only from a general point of view -or at least limited to the examination of substantial data- and then in terms of protection, therefore with reference to the procedural law). Therefore, I changed my approach and, after a first part of the work intended to clarify the terms of the debate on the advisability of maintaining two distinct categories (invalidity and non-existence), referring both to the period before and after the introduction of the substantive and procedural rules on invalidity, I continued
the analysis of the various applications as they came to my attention, prompted by and jointed to the examination of normative data. The result was a work whose appearance and purpose is essentially procedural. For this reason, the substantial aspects, due to the need of conciseness, although of undoubted importance, were addressed only " incidentally ", with the purpose of correctly understand and solve the numerous problems that emerged on the case . Article 31 paragraph 4 c . p . a., in particular, has been examined in detail in its architecture and in its formal structure, especially with reference to the complex regulation of the term and the reasons underlying it . It is in the discipline of the term that we find , in fact , the legislator's attention to the substantial figure , represented by the variety of interests , public as well as private , affected by the invalid measure. The analysis of the provision of the law continued with a comparative approach , with respect to institutions and categories that appear similar to the invalidity. That was in order to highlight the differences with the category of non-existence. Finally, the work provides a broad discussion of the possible forms of protection remedies available against the invalid measure in different areas - not only administrative , but also criminal – affected by the exercise of power
La Luce per l’impero. I cinegiornali sull’Africa Orientale Italiana 1935-1942
Get PDFIn my PhD dissertation I try to answer to the question on how the Fascist regime in Italy
represented its empire through the “Istituto Luce” newsreels, between the 1935 and 1942. Given the
lack of a comprehensive work on the above mentioned subject, I’ve investigated on how
cinematographic representations could shape or redefine the process of identity building during the
“Ventennio”.
In order to achieve a broad theoretical frame, in the first chapter I’ve analysed the roots of
the Italian fascist’s culture. The discourse as conceived by Michel Foucault is a key concept to
investigate about the relationship between power, knowledge and culture. I’ve used two theoretical
evolutions of the Foucault’s discourse, namely the visual discourse and the Orientalist theory. In so
doing I’ll be able to apply the concept in order to study the visual products about colonialism. Then
I’ve investigated about the history of Italian colonialism, focusing on both the invasion of Ethiopia
in 1935 and the reasons of the delay that characterized the early studies on the topic.
In the chapter two I’ve specified a methodological frame to understand the relationship
between Fascism and Italian masses through the newest mass media such as cinema and radio
broadcast; as a result I underline several concept of modernity which found place within the cultural
space of Fascism. The reconstruction of the “manufacture of consent” allows me a first examination
about the role of the “Istituto Luce” within the Fascist regime.
New archival records give me the possibility to a meticulous reconstruction of the activity of
the Istituto Luce during the Ethiopia’s war. Chapter three is about the “Reparto fotocinematografico
Africa Orientale dell’Istituto Luce” (RAO), which factually made imperial newsreels. Related to the
activity of the RAO, other two original aspects have been analysed: the activity of the “Ufficio
Stampa e Propaganda Africa Orientale” which had to coordinate the whole info-propagandistic
activity between Africa and Italy; then I’ve focused my attention on the diffusion of the cinema in
the “Africa Orientale Italiana” as a tool to reinforce racial borders between black and white people.
In the last chapter I’ve analysed 200 newsreels in order to investigate about the gap between
reality and cinematographic representations. Visual analysis is placed in the historical and
theoretical frame above mentioned: in this way I’m able to reconstruct the discourse on identity and
otherness that shaped these cinematographic representations
Scalable exploration of highly detailed and annotated 3D models
Get PDFWith the widespread availability of mobile graphics terminals andWebGL-enabled browsers, 3D
graphics over the Internet is thriving. Thanks to recent advances in 3D acquisition and modeling
systems, high-quality 3D models are becoming increasingly common, and are now potentially
available for ubiquitous exploration.
In current 3D repositories, such as Blend Swap, 3D Café or Archive3D, 3D models available for
download are mostly presented through a few user-selected static images. Online exploration is
limited to simple orbiting and/or low-fidelity explorations of simplified models, since photorealistic
rendering quality of complex synthetic environments is still hardly achievable within the
real-time constraints of interactive applications, especially on on low-powered mobile devices or
script-based Internet browsers.
Moreover, navigating inside 3D environments, especially on the now pervasive touch devices,
is a non-trivial task, and usability is consistently improved by employing assisted navigation
controls. In addition, 3D annotations are often used in order to integrate and enhance the visual
information by providing spatially coherent contextual information, typically at the expense of
introducing visual cluttering.
In this thesis, we focus on efficient representations for interactive exploration and understanding
of highly detailed 3D meshes on common 3D platforms. For this purpose, we present several
approaches exploiting constraints on the data representation for improving the streaming and
rendering performance, and camera movement constraints in order to provide scalable navigation
methods for interactive exploration of complex 3D environments.
Furthermore, we study visualization and interaction techniques to improve the exploration
and understanding of complex 3D models by exploiting guided motion control techniques to aid
the user in discovering contextual information while avoiding cluttering the visualization.
We demonstrate the effectiveness and scalability of our approaches both in large screen museum
installations and in mobile devices, by performing interactive exploration of models ranging
from 9Mtriangles to 940Mtriangles
La Metabolomica: una nuova era in Cardiologia. Le nostre esperienze originali nei campi dell' insufficienza cardiaca, della cardiopatia ischemica e dell' ipertensione polmonare
Get PDFPurpose. Metabolomics (MBS) is a “omics” science that enables the assessment of a broad range of
metabolites providing a metabolic picture able to identify metabolic changes. On these basis we
carried out a metabolomics on three settings of cardiovascular diseases: a) heart failure; b) Stable
coronary artery disease; c) Pulmonary hypertension in systemic sclerosis.
Heart Failure
Heart failure (HF) is characterized by a series of maladaptive metabolic changes, which have
recently been proposed as a new therapeutic target.
A proton nuclear magnetic resonance (1H NMR)-based MBS analysis was performed on blood
samples of 3 groups of individuals: nine control individuals (Group A); nine HF patients with mildmoderate
impairment of left ventricle ejection fraction (LVEF 35-50%; Group B); fifteen HF
patients with severe LVEF impairment (EF <35%; Group C). Specimens were analyzed with a 1HNMR
500MHz spectrometer. A supervised PLS-DA Projection on Latent Structures Discriminant
Analysis was applied to realize a descriptive model of HF. Morevoer, we carried out an
echocardiographic evaluation of whole study population, including an assessment of Longitudinal
Strain (S) and Strain Rate (SR) values using Speakle Tracking Imaging. The three groups showed a
progressive impairment of systolic function from Group A to Group C, with intermediate values in
Group B. The application of Pattern-recognition methods to 1H-NMR spectra identified 3 metabolic
clusters related to A, B and C groups, respectively. The discrimination were related to a metabolic
fingerprint depending on a limited set of metabolites. Our preliminary data show that MBS is a
sensitive method, which can be effectively used in association with traditional techniques for the
evaluation of HF. This new tool may permit to investigate the perturbed metabolic pathways in HF
and their correlation with impaired myocardial function and could lead to the identification of
innovative therapeutic approaches.
Stable coronary artery disease
Endothelial dysfunction is a key variable in the pathogenesis and progression of atherosclerosis and
its complications, particullary coronary artery disease (CAD). Current evidence suggests that
endothelial status is not determined solely by the individual risk factor burden but rather, may be
regarded as an integrated index of all atherogenic and atheroprotective factors present in an
individual. A 1H-NMR based MBS analysis was performed on (right and left) coronary blood
samples of 11 subjects (7 male, 4 female; mean age 66+/-12,87 years) enrolled after a stress
echocardiography suggestive for ischemia and undergone a coronary angiography (CA). On the
basis of the results of CA we classified patients in two groups: occlusive coronary atherosclerosis
(OCA) and microvascular disease (MD). A supervised Orthogonal Projection on Latent Structures
Discriminant Analysis (OPLS-DA) was applied to evaluate whether it is possible to realize a
descriptive model of the two different expressions of CAD. CA showed an OCA in 6 patients and a
MD in the other 5. OPLS-DA identified two clusters related to the CA groups, achieving good
values of R2 (R2y=0.994) and Q2 (Q2=0.905); these components featured a significant separation as
determined by ANOVA cross-validation (p<0.01). The metabolites of major importance in
determining clustering were: Alanine, Beatine, N-N-Dimethyl-glycine, Citrate, Lactate, Malonate,
Piruvate and Succinate. Afterwards, we applied an univariate statistical analysis to evaluate the
differences in concentration of these metabolites between groups; this analysis showed betaine and
DMG higher levels in patients with OCA when compared with those affected by MD
(0.3573±0.2324 μM vs 0.1340±0.1040 μM, p<0.03, and 0.0064±0.0032 μM vs 0.0030±0.0014 μM,
p<0.02, respectively). It is remarkable that these two metabolites are are related to the NO
metabolism and the endothelial function. MBS seems to be a sensitive method, which can be
effectively used in the study of CAD pathophysiology. The obtained results, if confirmed, could be
the basis of future researches on the role of vascular microambient in determinig the evolution of
atherosclerosis in the two different pathophysiological settings and could lead to the identification
of innovative therapeutic approaches.
Pulmonary hypertension (PH) in systemic sclerosis (SS)
Pulmonary hypertension (PH) in systemic sclerosis (SS) identifies a poor prognosis subset of
patients. Recent studies suggested a “metabolic theory” on the development of pulmonary arterial
hypertension. On these basis we carried out a metabolomics study in order to evaluate whether in
SS patients with increased Pulmonary Vascular Resistance (PVR) differences in pulmonary arterial
blood metabolites were identifiable. We studied 18 SS patients (age 58,7±15,6 years) free of
pulmonary fibrosis that underwent a clinical evaluation, a standard echocardiography with Tissue
Doppler and Speckle tracking Imaging and a right heart catheterization (RHC). A blood sample was
collected during the RHC in the distal peripheral circulation of the pulmonary arteries to perform
the metabolomic analysis. Specimens were analyzed with a 1H-NMR 500MHz spectrometer. An
Orthogonal Signal Correction (OSC) and a Projection on Latent Structures Discriminant Analysis
(PLS-DA) were applied. Based on PVR we divided the population in Group A (N=8; PVR<1.6 uW;
mean±SD = 1,16±0,23 uW) and Group B (N=10; PVR>1.6 uW; mean±SD = 2,67±0,67 uW.
p<0.001 vs Group A). No significant differences were identified in terms of anthropometric,
clinical, echo and terapeutic characteristics. At RHC the 2 groups showed a difference in mean
pulmonary pressures values (Group A: 20±4 mmHg; Group B: 25±5 mmHg), with mild PH in
group B. We applied an OSC using NMR data as the X-matrix and PVR values as the Y-matrix. A
clear clusterization was observed with the PLS-DA, achieving good values of R2 (R2X=0.364;
R2Y=0.889) and Q2 (0.721), with significative ANOVA cross-validation (p=0.003). The
discrimination were related to a metabolic fingerprint depending on a limited set of metabolites:
Group B was characterized by higher values of Lactate, Glycerol, fatty acids, Acetoacetate, Valine,
Leucine, Isoleucine and VLDL/LDL, whereas Group A showed higher values of Choline, Betaine,
Alanine, Glycine, Taurine, Arginine and 3-OH-butyrate; is worthy of note that all the compounds
relatively higher in Group A are related to the NO metabolism and the endothelial function.
Increased PVR seems to be related to specific metabolites strictly connected to the endothelial
dysfunction. Moreover MBS showed to be capable to finely identify the metabolic imbalance of
vasoactive factors able to determine and maintain the increased PVR. This approach could prove to
be useful in better understanding the pathophysiology of this severe complication of SS
Mining software repositories: measuring effectiveness and affectiveness in software systems.
Get PDFSoftware Engineering field has many goals, among them we can certainly
deal with monitoring and controlling the development process in order to meet
the business requirements of the released software artifact. Software engineers
need to have empirical evidence that the development process and the overall
quality of software artifacts is converging to the required features. Improving
the development process's Effectiveness leads to higher productivity, meaning
shorter time to market, but understanding or even measuring the software de-
velopment process is an hard challenge. Modern software is the result of a
complex process involving many stakeholders such as product owners, quality
assurance teams, project manager and, above all, developers. All these stake-
holders use complex software systems for managing development process, issue
tracking, code versioning, release scheduling and many other aspect concerning
software development. Tools for project management and issues/bugs tracking
are becoming useful for governing the development process of Open Source soft-
ware. Such tools simplify the communications process among developers and
ensure the scalability of a project. The more information developers are able to
exchange, the clearer are the goals, and the higher is the number of developers
keen on joining and actively collaborating on a project.
By analyzing data stored in such systems, researchers are able to study and
address questions such as: Which are the factors able to impact the software
productivity? Is it possible to improve software productivity shortening the
time to market?.
The present work addresses two major aspect of software development pro-
cess: Effectiveness and Affectiveness. By analyzing data stored in project man-
agement and in issue tracking system of Open Source Communities, we mea-
sured the Effectiveness as the time required to resolve an issue and analyzed
factors able to impact it
Dataset analysis for classifier ensemble enhancement
Get PDFWe developed three different methods for dataset analysis and ensemble enhance-
ment. They share the underlying idea that an accurate preprocessing and adap-
tation of the data can improve the system performance, without changing the
classification model. Correlation Score is a generic framework for assessing encoding
techniques by measuring the correlation between the encoded feature vectors and
the corresponding class labels; experiments show its effectiveness in discovering the
best encoding configurations between those tested, on a wide range of classification
domains. Multi-Resolution Complexity Analysis is a method for assessing the
local complexity inside a given domain. It is able to split a domain into regions
of different classification complexity, giving insights on the inner structure of the
populations inside the domain. Finally, Forests of Local Trees are a novel training
algorithm for ensemble classifiers. They are based on the concept of local trees:
classifiers trained with a bias toward a certain region of the domain. This bias
enhances the diversity inside the ensemble, leading to improved performance.
These three topics are meant as a foundation for a more complex framework, that
will eventually utilize them organically