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Truth and reality in Jürgen Habermas' Pragmatic Realism
Full text linkThe present work is divided into three sections. The first (only in Italian) is an analysis of some of
the main philosophical issues about the notions of reality and truth. The second section provides
both a historical reconstruction and a theoretical discussion of the notion of truth in the philosophy
of Jürgen Habermas. It shows how Habermas' approach to truth changes during the years. In the
'60s (chapter one) he maintains a weak kind of realism, connected to the idea of transcendental and
natural interests at the basis of an emancipatory, interpretative-practical and descriptive-technical
attitude. During the '70s Habermas enhances the role of communication, thus coming to a
“consensualist” theory of truth, where truth is linked to justifications obtained in discurses inspired
by an ideal speech situation (chapter two). Finally, he has recently come to a realist turn, linked to a
“Janus-faced” theory of truth (chapter three). The third section aims to assess whether and how this
last formulation is a realist approach to truth. Such an evaluation will unveil the hiding place for the
theoretical problems affecting Habermas' realist turn: the notion of objectivity
Metabolic studies on the nitrophile yeast Rhodotorula glutinis DSBCA06
Full text linkNitrogen is the most abundant element in atmosphere and fundamental component of proteins, nucleic acids and other essential molecules. In the past century the industrial use of nitrogen compounds has grown exponentially causing widespread pollution. Nitrogen pollution has wide-ranging impacts including contributions to global warming, acid rains and eutrophication.
Reduction of nitrogen use in industry and agriculture coupled whit remediation treatments could represent a solution.
To this purpose we isolated from environmental samples a nitrophile strain capable of removing nitrogen compounds efficiently from the medium. Through the molecular characterization, we identified the strain as a Rhodotorula glutinis that we called DSBCA06.
We examined the main metabolic features of the strain, also to determine the best growing conditions. At the same time, the ability of the strain to grow in presence of high nitrite concentrations was assayed, being a relevant feature poorly studied earlierfor other environmental yeasts. The ability of the strain to grow in presence of heavy metal cations was also tested, showing a noticeable tolerance.
The cost of bioremediation treatments is often a problem. One of the way to obviate this is to produce valuable secondary metabolites, capable of positively impact the cost of the processes. In this context the ability of the strain to produce carotenoids, natural molecules with antioxidant properties used for food production, cosmetic and pharmaceutical industry, has been evaluated.
The strain Rhodotorula glutinis DSBCA06 showed interesting features suggesting its possible use in bioremediation or industrials process for production of secondary metabolites such as lipids and carotenoids
Studies on the synergic activity of a three-drug cocktail active against cisplatin-resistant human leukemia and carcinoma cells
No full textObjectives. At the light of properties and limits of cisplatin (CDDP) as an anticancer agent, and in view of the potential clinical relevance of the synergic effect of CDDP with the Cu(II)-phen complexes previously reported against T-leukemia cells (Pivetta et al.,Talanta, 2013), my research project was aimed at (1) extending the studies of CDDP-Cu(II)-phen combinations as such, as well as with the addition of a third drug component; (2) determining the potential degree of selectivity of the most synergic drug combinations.
Methods. Most studies were focused on the most potent Cu(II)Phen compound (C0), lead of the cupper-phen complex series. Wild type and CDDP-resistant human T-leukemia CEM cells, wild type and CDDP-resistant human ovarian carcinoma A2780 cells, and ex vivo cultures of human peripheral blood lymphocytes from healthy donors, were used as cell models to characterize the cytotoxic activity of both binary and ternary drug combinations. Experimental Design (ED) and Artificial Neural Network (ANN) were used for setting experiments and for evaluation of data.
Results. Binary and ternary drug combinations showed statistically significant synergisms either against the CDDP-sensitive and the CDDP-resistant cancer cell models. The three-drug cocktail was the most potent with a markedly higher cytotoxicity against leukemic lymphocytes than against ex vivo healthy proliferating lymphocytes. An ESI-MS study of CDDP-C0 mixed combination showed the formation of copper-platinum adducts which, leading to the release of a phenantroline moiety, may -at least in part- explain the synergism observed in the cell models. In addition, the analysis of phospholipid profiles showed lipid alterations in the CDDP-resistant CEM and A2780 cells with respect to their parental counterparts.
Conclusions. Besides of the need of further studies to unveil the molecular target(s) of the triple-drug cocktail, based on the promising selectivity index (SI = 5) for cancer cells, investigations on its effectiveness in a xenograft mice models of human susceptible and CDDP-resistant ovarian carcinoma are on the way
Essays on internal migration determinants. From a macro to a micro approach
Full text linkItaly has a long history of internal migration. The arguments addressed by the researchers in the last century cover two main questions: where migrants go, and who they are. This thesis focuses on these aspects using two different approaches.
The first study is based on a macro-approach. By means of a spatial gravity model, we investigate the determinants of internal migration using bilateral flows across Italian regions in the period 2000-2013. We address the issue of cross-regional dependence arising from the existence of regional spillovers by including spatial lags of the explanatory variables. The main results indicate the importance of spatial dependency induced by neighbouring regions at origin, and at destination. Interesting results are found for two different sub-sample of population: foreigners and Italians.
The second study focuses on individuals’ behaviour. Weighted logit models of the probability that an individual changes his or her region of residence from one year to the next over the 2011–2012 periods are estimated using Labour Force Survey data. Our results show that alongside strictly economic determinants, migration choices are driven by a large set of personal, professional, and family characteristics
Wideband digital instrumentation for the Italian radio telescopes
Full text linkItaly has a key role in the radio astronomical international context thanks to large
collaborations like the VLBI (Very Long Baseline Interferometry) in which all three radio
telescopes (Sardinia,Medicina, Noto) are deeply involved.
However, also the single dish activity represents a great opportunity to understand
the fundamental laws of nature in the Universe.
Usually, in the past, ad-hoc digital backends were developed for each particular scientific
goal; however, although highly optimised, they very often do not keep upwith the
times. In addition to the absent versatility even if based on reconfigurable FPGA-based
hardware, the major issue why digital backends are often obsolete - even before they
can be fully exploited - is the very long time necessary to make them integrated into the
software controlling the radio telescope.
In this thesis, a different approach - both regarding hardware and software - has
been developed to overcome aforementioned drawbacks and is described here. The unprecedented
achieved scientific results are presented in different fields (imaging, polarimetry,
spectroscopy, pulsars), and confirm the forcefulness of the adopted solution.
The versatility of the proposed infrastructure also allows us the development of innovative
spectrometers, which are able to meet the main requirements astronomers asking
us: wide-bandwidth, high-spectral resolution and an uniform passband response
(namely, no spectral “holes”). Finally, we describe an innovative infrastructure for the
SETI (Search for ExtraTerrestrial Intelligence) international program. In particular, the
KLT (Kahrunen-Loeve Transform) has been investigated togetherwith the FFT approach
usually adopted
La scelta della Fair Value Option nello IAS 40: evidenze empiriche sul settore Real Estate
Full text linkThe adoption of IAS/IFRS by the European Union has represented a key accounting change for European companies and offers a rich source of analysis to the scientific community. This thesis is part of the debate on-going on the choice between fair value and historical cost as the optimal evaluation criterium. The empirical research focuses on the accounting standard IAS 40, which is particularly suitable for this type of investigation as it is one of the few principles that allow the right to choose between the above mentioned assessment criteria (i.e., fair value and historical cost). In particular, IAS 40 deals with the accounting evaluation and representation of investment property in the financial statement. Investment property represents any fixed asset held for the purpose of obtaining profits in the form of rent or capital gains. The empirical investigation focuses on companies belonging to the real estate industry, because, as showed by previous research, companies belonging to this industry have significant investment properties as accounting entries on total assets. Therefore, the accounting choice between fair value and cost should have a greater impact on the balance sheet. A preference for a given option in connection with certain firm characteristics is expected. The empirical research is conducted on a sample of listed real estate companies based in four European countries (France, Germany, Sweden and Italy) that draw up consolidated financial statements. In particular, it investigates the determinants of the first-application choice between fair value and historical cost in 2005, when international accounting standards were adopted for the first time. By analyzing the firm characteristics in the four-year period preceding the choice (period 2001-2004), the thesis investigates the main determinants (financial position, leverage, return on investment and company size) of the “fair value vs cost” accounting choice. As control variables, the variables “sector” and “country” are included. The
results show that financial position, leverage and return on investment do not drive the choice of opting for fair value rather than historical cost. This evidence may imply that the motivation underlying this choice is independent from accounting evaluations, but mainly oriented to the adequate development of corporate real assets by selecting the more suitable criteria. Moreover, it is found that the company size is lower for those firms that chose fair value rather than cost. This result can be due to the fact that, as the company size increases business complexity and, therefore, the so-called “agency costs”, companies might opt for the cost method to reduce agency costs. The cost method, indeed, is perceived more reliable and verifiable and companies might prefer it to the information relevance of the fair value. In addition, as expected, a positive relationship between the fair value adoption and medium-long term investment activities in the real estate is found. Finally, Swedish firms, that belong to an Anglo-Saxon context, are more likely to adopt fair value. In conclusion, this work provides a contribution to accounting regulatory bodies, suggesting that the choice of fair value does not seem driven by opportunistic considerations but rather by the assessment of the effective value of real estate investments
Simulazione energetica di scenari per la produzione combinata a servizio di edifici civili in area mediterranea
Full text linkIncreasing regulation on greenhouse gas emissions aimed at fighting climate change has
significantly boosted construction and architecture sectors. Recent European directives
(2010/31/UE e 2012/27/UE) promote the reformulation of energetic planning rules and the
adoption of environmental-friendly models including the nearly zero-energy buildings, which
can be realised through increased energy efficiency, optimised energy production and the
systematic use of renewable energies. In this context, the civil sector plays a key role in both the
erection of new buildings and in the retrofitting of the existing ones, especially with respect to
energy production.
The present work aims at studying plant design technologies and configurations for the
combined production in civil buildings, focusing on the problematic energy situation of the
Mediterranean region. The study resulted in the development of a calculation code (in Matlab
environment) for the energetic simulation of different scenarios of combined production, which
used high-efficiency on market technologies based on renewable energies.
Comparing different solar energy conversion technologies, co-trigenerative solutions and
solar cooling systems for a Mediterranean-like electricity consumption, and using the calculation
code herein developed, it was possible to analyse the energetic behaviour and to determine its
main environmental and economic-financial parameters. The consequent sensitivity analyses
highlighted the significant incidence of energetic costs and of the efficiency parameters of the
single technologies, reflecting the substantial differences observed in the final results of the
simulations
Characterization and comparison of microbial communities from different tourist ports in Mediterranean Sea and evaluation of applicability of bioremediation treatments
Full text linkMarine ecosystems represent the greatest volume of the biosphere and the largest surface of the planet. They are home to an enormous diversity of animals, plants and microbes and are crucially important resource for fishing, transport, mining and recreation. Humans have been dependant on the seas and oceans for many millennia and have used the coastal waters as a prehistoric resource for food and expansion around the planet (Moore et al., 2013). Coastal region are frequently areas of great natural beauty and are used extensively for recreation and tourism as reflected in the mass migration of people to the coasts in the holiday seasons (Golyshin et al., 2003).
The Mediterranean has become one of the most demanded destinations for organized touristic routes (increasing cruising market) and "self-made" ones (boating and chartering). Despite the strict link between tourism development in coastal areas and port facilities, the sector growth has not been sustained neither by an adequate expansion nor by an adaptation of the ports.
Ports have a decisive role in the development of coastal areas and the risk of impact of infrastructures construction and maritime traffic on the coastal zone is high. Ports are part of the logistics chain and the transport networks with a decisive role in the development of coastal areas. However, the risk of impact of infrastructures construction and maritime traffic on the coastal zone is high. The problem with any port expansion is the balance between environmental and social-economic issues (sustainable development). In fact, if on one hand the development of infrastructures has to take into account environmental impact and restoration to ecological standards, on the other hand, denial of port expansion for environmental reasons may favour other competing ports.
Due to their strategic location between sea and land, ports are particularly critical environments as they can receive pollution coming from land, ships and from the port facilities themselves. Furthermore, ports are not closed systems and their pollution may impact large parts of the adjacent coastal areas. Specifically, pollution by petroleum hydrocarbons is one of the major environmental problems in ports and it is mainly associated with the heavy ship/boat traffic and the related facilities located in these areas. The ship transport in ports is powered by diesel.
The present study was carried out in the framework of the MAPMED project (Management of Port areas in the Mediterranean Sea Basin). The general objective of the project was to improve the environmental sustainability of tourist coastal areas in the Countries of the Mediterranean Sea Basin through the promotion of a long term cooperation between Institutional Authorities and the scientific community and, at a more specific level, to optimize, validate and transfer tools to guide Institutional Authorities in the sustainable management of tourist ports/harbours with regard to monitoring and reduction of hydrocarbon pollution.
Strategies for cleaning up hydrocarbon pollution are greatly affected by a variety of factors, such as type of oil, characteristics of the spill site, and occasionally political considerations. A number of approaches and technologies have been developed for controlling oil pollution in marine environments. Bioremediation has emerged as one of the most promising treatment options for oil removal since its successful application after the 1989 Exxon Valdez spill.
The general objective of this work was to evaluate and compare the applicability of different bioremediation approaches of seawaters and sediments in Mediterranean tourist ports. Particularly, it was directed to contribute to the answer to two following main questions:
-Do different tourist ports share the same bacterial communities?
-Do bioremediation strategies have similar applicability in different tourist port areas?
The specific aims of the present study were:
1. Definition and comparison of the pollution status of seawater.
2. Comparison of the bacterial communities in seawater.
3. Characterization of the dominant cultivable hydrocarbon-degrading bacteria from seawater and sediments.
4. Comparison of the effects of biostimulation treatment on bacterial communities in seawater at laboratory scale.
5. Comparison of the effect of bioaugmentation treatments on PAH degradation in sediments at laboratory scale.
Three tourist ports located across the Mediterranean Sea were selected as case study sites representative tourist harbours in the Basin: Cagliari (Sardinia, Italy) in the western part, El Kantaoui (Tunisia) in the central part, and Heraklion (Crete, Greece) in the eastern part. Beside their geographic position, port selection was also based on other different elements, such as categories of maritime traffic, port dimension and existing information on pollution. The maritime traffic inside the three tourist ports is represented by recreational boats, passenger ships and fishing vessels. In addition to the marine traffic, the major pollution sources related to the three port areas are wastewater discharges into the sea, river mouth, fuelling stations, and fishing activities.
Data demonstrated that Cagliari port was characterized by a high level of eutrophication. Coherently with the high nutrient load, the viable title of heterotrophs was one-log higher in the seawater of Cagliari port when compared with values found in the other ports. The structure of the microbial communities in seawater from Cagliari and El Kantaoui were more similar to one another than the others while Heraklion presented different community structures.
During the biostimulation treatment in seawater microcosms, comparable degradation kinetics were found for Cagliari and Heraklion sites. Furthermore, nutrient amendments in El Kantaoui microcosms resulted in a two-fold increase in the degradation rates as compared to the other two port areas. The structures of the bacterial communities of El Kantaoui were more homogenous than those from Cagliari, while Heraklion presented a moderate change in community structures during bioremediation treatment. Moreover, different community structures were found for the three sites at the end of the treatment.
The community of cultivable degraders from seawater of the Cagliari port was dominated by copiotrophic bacteria belonging to the genus Pseudomonas whereas the majority of the isolates from Port El Kantaoui were Alcanivorax. Both OHCBs and non-professional hydrocarbonoclastic bacteria were equally represented in the community from Heraklion port.
The autochthonous population from the sediments of El Kantaoui does not possess the metabolic routes necessary to metabolize BaP being the addition of an allochthonous strain a successful strategy for promoting BaP degradation. Thus, a selectivity of the bioaugmentation treatments was demonstrated both in terms of typology of PAHs and sediments
Structural and functional analysis of human voltage-dependent anion channel isoforms (hVDACs): Combining in-vitro and in-silico approaches
Full text linkVDACs are a small family of conserved proteins located in the outer mitochondrial membrane.
They conduct ions, metabolites and small molecules, among which the energetic nucleotides ATP,
ADP and NADH.
Three different VDAC isoforms have been characterized in higher eukaryotes, encoded by three
separate nuclear genes. VDAC1 is the most abundant isoform in most cells, being ten and hundred
times more prevalent than VDAC2 and VDAC3, respectively. It is thus not surprising that VDAC1
is the isoform most extensively characterized. Functionally, VDAC1 is anion selective and exhibits
a single-channel conductance of ~3.5-4.0 nS in 1 M KCl at an applied voltage between -20 mV and
10 mV. Raising the applied voltage results in the channel switching to the so-called “closed state”,
with a lower conductance and a channel selectivity reversed to cations. In addition to the poreforming
function, VDAC1 has been involved in various interactions and cross-talk with other
cellular proteins like hexokinase, tubulin, the Ca2+ gate into mitochondria and the Bcl-2 family
members that can impact on the activity of the pore itself and vice versa, testimony to the
involvement of VDAC to crucial cell fates like in pathways leading to apoptosis, cancer and
degeneration
The aim of the PhD project was to perform a comparative study on the human VDAC isoforms
focusing on both the whole channels and the individuals N-terminal domains. In this sense, both
experimental and computational techniques have been used pointing out their complementarity and
contribute to the completeness of the study.
After a brief introduction, the methods used during the PhD will be presented. In the third chapter,
the results together with the discussion will be described. Firstly, focusing on the structural
characterization of the N-termini of the three isoforms. Secondly, the results and the discussion will
concern the comparative study of the entire channels. Both of these characterization have been
performed with either experimental and computational techniques.
Finally, in the 4th chapter a brief conclusion and an outlook on a future perspective will be given
Effetto dell’esposizione cronica volontaria di eroina e WIN55,212-2 sull’espressione di micro RNA nelle aree cerebrali coinvolte nella dipendenza da sostanze d’abuso
No full textMicro RNAs (miRNA) are 21-25 nucleotide endogenous non coding RNAs that regulate gene expression at the post-transcriptional level through binding to a target complementary mRNA. Targeted mRNAs are translationally inhibited or subjected to degradation by miRNAs, depending on the complementarity in the 3’UTR of the mRNAs.
Long-term intake of drugs of abuse results in persistent perturbation of synaptic plasticity, progressing towards high risk, drug-seeking behavior and relapse. The molecular mechanisms leading to addiction are still poorly understood but emerging evidence suggests that drug induced neuroplasticity depends on epigenetic changes in gene expression and post-transcriptional regulation.
MiRNAs have been implicated in the mechanisms of drug addiction, and further studies may be central for a better understanding of their potential role as novel therapeutic targets of this disorder. Different miRNAs may respond to different drugs and regulate diverse pathways. Thus they can specifically affect the development of synaptic connections and plasticity, direct dendrite formation in neurons, and have an important role in the development of addiction-related behaviors.
The aim of this study was to identify the correlation between miRNAs regulation and addiction in four reward related areas (NAc shell, NAc core, PFCX, CPu) following heroin and WIN55,212-2 self-administration (SA). The SA model used in this study is a well-established drug addiction model that provides great face validity to human drug intake.
In order to evaluate changes in miRNAs expression we performed miRNome microarray analyses on RNA. We also measured the mRNA levels of 11 different genes, known to be involved in addiction and which were predicted as potential targets of some miRNAs found dysregulated in our esperiment.
Lastly, we performed a western blot analysis in order to assay the proteins expression profile following heroin SA. Future studies are required to evaluate protein expression following WIN55,212-2 SA.
We identified several miRNAs in which the expression was modified after heroin SA. We found 39 miRNAs dysregulated in NAc shell: 16 upregulated (FC>2) and 23 downregulated (FC<-2); 114 miRNAs dysregulated in NAc core: 97 upregulated and 17 downregulated; 125 miRNAs dysregulated in the caudate putamen: 105 upregulated and 20 downregulated and 51 miRNAs dysregulated in the prefrontal cortex, 39 upregulated and 12 downregulated.
Following WIN55,212-2 SA we observed that 95 miRNAs were differentially expressed in NAc shell: 40 upregulated (FC>2) and 55 downregulated (FC<-2); 96 miRNAs were dysregulated in NAc core: 13 upregulated and 83 downregulated; 110 miRNAs dysregulated in the caudate putamen: 11 upregulated and 99 downregulated; and 53 miRNAs in the prefrontal cortex: 26 upregulated and 27 downregulated.
Gene expression analysis in the heroin group showed 2 genes downregulated in NAc shell (BDNF, FC=-2.78 and CCKBR, FC=-1.85), 3 downregulated in NAc core (DRD3, FC=-2.38, MeCP2, FC=-2.14 and NOS1 FC=-
1.94), 2 upregulated in the caudate putamen (BDNF, FC=2.74 and CREB, FC=2.09). No changes were found in the prefrontal cortex following heroin SA.
As regard WIN55,212-2 SA, only 1 gene was upregulated in NAc core (BDNF, FC=2.16). A strong dysregulation was observed in the caudate putamen: 9 were upregulated (CREB, FC=7.20; CLOCK, FC=3.44; DRD3, FC=4.23; NOS2, FC=6.75; SIRT2, FC=11.53; NOS1, FC=11.05; MECP2, FC=11.03; SIRT1, FC=6.30; OPRM1, FC=3.89) and 1 downregulated (BDNF, FC=-2.23). We identified only 1 gene downregulated in the prefrontal cortex (BDNF, FC=-2.15). No changes were observed in NAc shell.
Protein expression analysis revealed that the levels of BDNF, MeCP2 and pCREB were decreased in NAc shell. Only CCKBR protein expression was increased in NAc core, whereas MECP2, NOS1, CLOCK, CREB, pCREB, BDNF, SIRT2 and MOR1 proteins were downregulated. MeCP2 was upregulated and CREB, BDNF, CLOCK, pCREB, NOS1 and SIRT1 were downregulated in the caudate putamen. In the prefrontal cortex 4 proteins showed downregulation: BDNF, p-CREB, SIRT1 and MOR1.
This study provides insight into the effect of heroin and WIN55,212-2 on miRNA and gene expression in key brain areas associated with addiction, supporting the hypothesis that long-lasting changes may occur in the expression of genes after opioids and cannabinoids consumption. The influence of miRNAs on the regulation of gene expression suggests that miRNAs may play a role in the vulnerability to addiction.
The present findings give a hint for further studies and are important in terms of their translational potential. In fact, understanding how miRNAs affect gene regulation may be helpful for developing therapeutic strategies for the treatment of addiction