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Synthetic biology, concerns and risks: looking for a (constitutionally oriented) regulatory framework and a system of governance for a new emerging technology
Get PDFThe Doctoral thesis is about the relationship between synthetic biology and the law. It aims at elaborating a model of governance and regulation against the risks of synthetic biology, using the "prudent vigilance" approach and the human rights frame.
Synthetic biology occupies a relevant position among the new emerging technologies. The potential applications of this field of research, characterized by the adoption of an engineering approach to life, together with a trend to converge between different technologies, span several fields. However, it could also generate numerous risks.
This thesis aims at individuating a regulatory framework and a model of governance for addressing the risks and concerns arising within synthetic biology area. This is to ensure that the progress is not hindered but, at the same time, the problematic issues are not neglected or under evaluated. The suggested model is named "prudent vigilance" (inspired by the report about synthetic biology, drafted by the U.S. Presidential Commission on Bioethics, 2010), and it entails an ongoing and periodically revised process of assessment and management of all the risks and concerns, taking into account the interests of all the stakeholders in a dynamic, cooperative, democratic, open and transparent manner. Furthermore, it suggests the adoption of policies that are based on the principle of proportionality (among benefits and risks) and on a reasonable balancing between different interests and rights at stake. These policies should be taken through "hard law" and "soft law" sources, thus involving "actors" at all levels (governments, institutions, the scientific community and general public), and the enforcement and control of those policies should be exercised by judges coupled with independent professional bodies, where all the stakeholders are represented. The policies should also be oriented by a constitutional frame, that is represented by the protection of fundamental human rights emerging in the field of synthetic biology (right to life, right to health, dignity, freedom of scientific research, right to environment).
After the theoretical explanation of the chosen model, the operability of it is "checked", by considering, as a case study, its application with reference to a specific risk brought up by synthetic biology - biosecurity risk, i.e. the risk of bioterrorism
p53 Functional Interactions: the Study of a New Crosstalk with Estradiol Pathway in Transcriptional Responses to Chemotherapeutics
No full textBACKGROUND: Objective of this thesis has been the analysis of the sequence specific transcription factor p53, a critical tumor suppressor protein, specifically, the crosstalk (or functional interactions) with other transcription factors, namely, the estrogen receptors, and the modeling in reconstituted assays of the interaction of p53 with positive and negative cofactors (e.g. MDM4 and 53BP1) and the impact of small molecules, including chemotherapeutic drugs, on such interactions. Previous reports have revealed a complex, often negative, crosstalk between p53 and estrogen receptors (ERs) related in part to the physical interaction between the two proteins. An example of transcriptional cooperation mediated by cognate, non-canonical cis-elements was instead discovered for the angiogenesis related VEGFR1, FLT1 promoter.
MAIN TASK: Transcriptional cooperation between p53 and ERs was sought out on a global scale using the human breast adenocarcinoma MCF7 cells as a model and transcriptome analyses. Cells were subjected to single or combinatorial treatments with the chemotherapeutic agent doxorubicin (able to induce p53 protein stabilization) and the ER ligand 17β-estradiol (E2). 201 differentially expressed genes, that showed limited responsiveness to either doxorubicin treatment or ER ligand alone, but were up-regulated in a greater than additive manner following combined treatment were identified. Among sixteen genes chosen for validation using quantitative real-time PCR (qPCR), seven (INPP5D, TLR5, KRT15, EPHA2, GDNF, NOTCH1, SOX9) were confirmed to be novel direct targets of p53, based on responses in stable MCF7 clone cells silenced for p53, or cooperative targets of p53 and ER. Based on exposure to 5-fuorouracil (another genotoxic drug) and nutlin-3a (a non-genotoxic p53-specific activator), the combined response identified genes that were consistently regulated, although with different kinetics (e.g. INPP5D, CDH26, KRT15), while others (e.g. TLR5, SOX9) were treatment selective.
Promoter pattern searches and chromatin IP experiments for the INPP5D, TLR5, KRT15 genes were also performed to interrogate a direct, cis-mediated p53 and ERs regulation. While these analyses confirmed the identification of novel direct p53 targets, the important contribution of ER in their transcriptional modulation and the role of non-canonical response elements, the correlation between occupancy levels and gene expression varied.
SECONDARY TASK: Using a newly developed miniaturized yeast-based assay, functional interactions between p53 and its regulators MDM4 and 53BP1 was investigated. MDM4 was confirmed as a p53 negative regulator and the impact of nutlin-3a or RITA (apoptosis inducer through p53 binding) on the p53-MDM4 interaction was explored. Instead, no stimulatory effect of the p53 co-activator 53BP1 was detected.
CONCLUSIONS: Collectively, the results indicate that combinatorial activation of p53 and ER can induce novel gene expression programs which have implications for cell-cell communications, adhesion, cell differentiation, development and inflammatory responses as well as cancer treatments. The yeast-based assay represents a versatile tool to study p53 interactions with cofactors
Energy and Urban Planning: towards an Integration of Urban Policies
No full textThis PhD research focuses on the Italian case and analyses the possibility of integrating energy planning with spatial planning, the effectiveness of plan implementation mechanisms, and the prospect of replacing public-led interventions with market tools. Recent innovations in the legislative framework support the inclusion of energy saving and climate change adaptation and mitigation goals in plan implementation procedures
Tecniche digitali di modellazione 3D applicate alla ricerca e documentazione archeologica
No full textOggetto di questa ricerca è l’esame di alcuni aspetti relativi all’applicazione di sistemi informatici finalizzati alla modellazione tridimensionale in contesti archeologici, con particolare attenzione alle ricadute scientifiche nelle indagini e nella documentazione. Sono state quindi affrontate le problematiche connesse con la creazione di modelli tridimensionali dell’esistente tramite strumenti di rilevamento diretto e la possibilità di una verifica delle alte potenzialità connesse con questi sistemi, anche grazie all’analisi dell’effettivo apporto della disciplina archeologica e del ruolo che la figura dell’archeologo deve assumere, alla luce delle crescenti problematiche tecniche emerse nello sviluppo delle ricerche.
Le analisi si sono articolate in primo luogo nell’ambito del progetto multidisciplinare APSAT (Ambiente e Paesaggi dei Siti d’Altura Trentini) e in particolare nella sezione (Attività 5) "Rilievo dei siti tramite fotogrammetria, laser scanner, stazione totale e GPS", curata dalla Fondazione Bruno Kessler di Trento, attraverso l’esame di una serie di casi-studio dedicati ad alcuni castelli e siti trentini (Castel San Michele a Ossana, Castel San Pietro a Ton, Calvola a Tenno, Riparo Gaban, loc. Martignano e Riparo Dalmeri a Grigno).
La ricerca ha affrontato quindi altri casi particolarmente significativi per le specificità rilevate (tombe etrusche a camera dipinte, il frontone del Tempio A di Pyrgi a S. Marinella, RM, l’area archeologica di Paestum a Capaccio, SA), per l’applicazione in ambito archeologico professionale (scavo archeologico nell’area della città etrusca di Marzabotto, BO, rilevamento e analisi della stratigrafia muraria dell’area del Teatro romano di Ventimiglia, IM), nonché per l’elaborazione di modelli e ricostruzioni tridimensionali per la divulgazione scientifica (supporti da modello 3D per la fruizione della Tomba della Caccia e della Pesca a Tarquinia, VT, supporti per la mostra internazionale itinerante "Etruschi in Europa", Videowall del nuovo Museo delle Scienze (MUSE) con la rappresentazione dell’evoluzione della Conca di Trento).
E’ stato così possibile mettere in luce il valore dell’esperienza diretta dell’archeologo come una delle istanze fondamentali dell’evoluzione scientifica in questo campo, in grado di indirizzare in modo determinante le scelte e gli obiettivi specifici dell’esecuzione dei rilevamenti tecnici.
Chiave specifica della ricerca è quindi la possibilità di generare una riflessione mirata sulle problematiche tecniche direttamente connesse con l’archeologia allo scopo di cogliere il significato che la modellazione tridimensionale assume all’interno della disciplina e dell’evoluzione della metodologia della ricerca
La liberta' personale e le neuroscienze cognitive
No full textL’emersione di nuove scoperte scientifiche e lo sviluppo di nuove tecnologie hanno portato a un ripensamento del tema della prova scientifica nel processo penale in prospettiva interdisciplinare. Se, da un lato, la ricostruzione probatoria dei fatti di reato è sempre più affidata ai risultati della prova tecnico-scientifica, dall’altro agli
strumenti tradizionalmente noti se ne stanno affiancando di nuovi, la cui affidabilità e rilevanza è spesso controversa. La presente ricerca nasce dall’interesse verso il recente affacciarsi nel panorama giuridico di strumenti e prospettive scientifiche relativamente nuove, come le neuroscienze cognitive e le tecniche a esse collegate.
Se, da un lato, vi è un grande interesse da parte di giuristi e scienziati ad approfondire il tema, dall’altro però l’indagine è ancora disorganica, dispersa tra
tematiche diverse, con profili di approfondimento che mutano anche a seconda della prospettiva che si assume: nazionale o internazionale, giuridica o multidisciplinare.
L’ambito di riferimento del presente lavoro, è quello dell’utilizzo delle neurotecniche nel processo penale. Si possono rilevare diversi piani sui quali si può condurre l’analisi: a) Un piano di tipo penale-sostanziale, con riferimento all’accertamento dell’imputabilità; b) Un piano di tipo procedurale, con riferimento all’ammissione della prova scientifica nel processo c) Un piano di tipo costituzionale, con riferimento alla protezione dei diritti fondamentali dell’imputato. Questi tre livelli sono, in realtà, strettamente interconnessi e la libertà personale è il presupposto e il punto di arrivo dell’indagine penale: la sua protezione o compressione costituiscono il fil rouge di tutti i piani di analisi, dal momento che la custodia cautelare e la pena detentiva sono una violazione, pur giustificata da esigenze di giustizia e di prevenzione, ma pur sempre violazione, della libertà personale di un essere umano. E va notato come, una volta che si sia assunta l’idea
ampia di libertà personale che le corti costituzionali ormai hanno esplicitamente affermato (in Italia, si pensi alla sentenza n. 471 del 1990), potenziali altre violazioni
ad essa, nella sua dimensione psicofisica, si possono riscontrare in altri momenti e per altre parti del processo, come per esempio, con riferimento alle modalità di
escussione del teste /acquisizione della prova nel corso del processo. Da ciò discende la centralità, nel valutare il modo in cui alcune recenti scoperte scientifiche e le tecniche connesse possano incidere sul diritto penale, della
protezione della libertà personale dell ’imputato e delle parti del processo, e di come essa sia regolata nei diversi sistemi e posta in evidenza nella casistica giudiziaria.
Queste considerazioni sono centrali nella presente ricerca: partendo dal fatto che la libertà personale costituisce un presupposto condiviso nei contemporanei sistemi giuridici occidentali, si è mirato a osservare il modo in cui si atteggia il rapporto tra tale libertà dell’imputato (e delle altre parti nel processo) e il potere autoritativo dello stato nel processo penale, laddove le nuove tecniche neuroscientifiche hanno applicazione.
L’analisi è stata condotta in una prospettiva comparata tra il sistema giuridicocostituzionale italiano e quello statunitense
Bilingual Education in the Primary School: Curriculum Study and Experimental Research on Language of Acquisition Effects in the Arithmetic Facts
No full textTeaching and learning in a foreign language: the CLIL approach in Europe, in Italy, in Trentino.
Monitoring a CLIL pilot programme at Primary school in Italy: Context Analysis and Curriculum Study.
Arithmetic facts and language of acquisition effects in Primary school children: Experiment 1,2,3 and 4.
Arithmetic facts in Primary school children:Does the language of acquisition really matter? Experiment 5 and 6
Erbium and Silicon Nanocrystals based Light Emitting Devices for lightwave circuits
No full textThe thesis is divided into two topics: silicon nanocrystals based light emitting devices and erbium doped silicon nanocrystals devices. I have studied silicon nanocrystals based devices. Here I have demonstrated the role of the different injection mechanisms in determining the efficiency of the device. I have studied single and multilayer structures, both in diode or transistor configurations. Lastly, the time dependence of the electroluminescence has been studied, clarifying the role of bipolar or unipolar injection in these structures.
On the second part of my thesis, I have studied Er and silicon nanocrystals co-doped devices. Firstly, the study was aimed at the understanding of the efficiency of the electrical pumping of Er ions. Then, integrated optical cavities were designed and fabricated and their optoelectronic properties measured. Here I built a specific set-up in order to measure at the same time the optical and electronic properties of active devices on wafer. Unfortunately, the measurements demonstrated that many nonlinear loss mechanisms set in when the devices are heavily injected with current. Therefore, despite the optical cavities are of high qualities, the system did not show any laser emission. On the other hand, I have demonstrated a fully integrated system where the Er doped injection device pumps a waveguide and the emission is then extracted through a grating. Last result was the experimental verification of the existence of intermediate band states through which the silicon nanocrystals to Er energy transfer occurs
Polyolefin nanocomposite with different types of nanofillers
No full textThe PhD project was details on the polyolefin nanocomposites compounding, processing and preparation. Two different types of polymer matrix with low melt flow rate for fiber forming polymers have been selected; high density polyethylene (HDPE) and isotactic polypropylene (PP). High density polyethylene was compounded with double layered hydrotalcite (LDH) while in case of polypropylene reinforcement by adding fumed silica and kaolinite was performed. In this way the influence of the nanofiller type on the thermo-mechanical properties of the prepared nanocomposites were studied.
In recent years several research efforts have been focused on the preparation of polymer/layered inorganic nanocomposites because of the excellent properties in comparison to the neat polymer. The main reason of this interest lies certainly in the properties of the nanoclay, like high stiffness, and high aspect ratio, that induce enhancement of various polymer properties (thermal stability, mechanical properties, flame resistance and gas barrier) even with small amount of filler. Moreover, nanocomposites can be processed more easily than microcomposite. Recently literature evidences a lot of progress in the nanofilled bulk materials; on the other hand, there are relatively a few publications on fibers made of nanofilled polyolefins. For instance, PP fibers were produced with various types of nanofillers, e.g. layered silicates, carbon nanotubes and montmorillonite. In the case of HDPE, composite fibers containing calcium carbonate, carbon nanotubes, silica and layered silicates were reported. It is worth to mention that so far, no publication could be found on this work using the same nanofillers with the same matrix.
This thesis is divided into six chapters; Introduction and Background, Experimental activities, after obtained Results with discussions are reported and finally Conclusions.
In the Introduction and Background (Chapter I and II) general information about nanocomposites and characteristic of different nanofillers type were summarized. After that polymer processing method with particular attention on the melt extrusion and fiber spinning were described.
Third Chapter is dedicated to the experimental part. Here, the used material characterization, nanocomposite preparation procedure and description of experimental techniques were reported. All nanocomposites were characterized by different experimental techniques. First nanofiller morphology by microscope (SEM and TEM) and X-ray diffraction technique was tested. Thermal stability was investigated by Thermal Gravimetric Analysis (TGA) and crystallization behavior by Differential Scanning Calorimetry (DSC). Finally mechanical properties were characterized by tensile test, Dynamical Mechanical Thermal Analysis (DMTA) and creep test.
The Results and Discussion have been divided into two parts; first one was dedicated to the high density polyethylene layered double hydrotalcite nanocomposites (HDPE-LDH), while in the second polypropylene with fumed silica (PP-FS) and kaolinite (PP-K) nanocomposite were described.
i. High density polyethylene hydrotalcite (HDPE-LDH) nanocomposites after different process of plates and fibers production will be compared in Chapter IV. At the beginning a polypropylene matrix, suitable for fiber production, was firstly melt compounded with organically modified hydrotalcite up to 5% by wt. Similar compositions with up to 3% wt. of LDH were performed by melt spinning. The incorporation of the clay into both bulk and fiber nanocomposite enhanced the thermal stability and induced heterogeneous nucleation of HDPE. Hydrotalcite positively affected the mechanical properties in term of higher Young’s modulus and tensile strength.
After the preliminary characterization on bulk and as-spun material the fibers were hot drawn up to draw ratio (DR) 20. XRD analysis revealed intercalation with high degree of exfoliation for the composites with 1-2% wt. of LDH. For this compositions higher elastic modulus 9.0 GPa - 9.3 GPa (with respect to 8.0 GPa of the neat HDPE), and maintain tensile strength and deformation at break were observed. Moreover, the addition of low amount of LDH significantly improved the creep stability.
ii. Nanocomposites of isotactic polypropylene fumed silica (PP-FS) were described in the Chapter V. Two types of hydrophobic fumed silica with different surface area (170m2•g-1 and 150m2•g-1) and surface treatment (treated respectively by dimethyldichlorosilane and octylsilane) up to 2% vol. were used. Similar as in case of HDPE-LDH nanocomposites plates production and characterization was a preliminary step to select the best compositions for the fiber preparation. After that, the work has been focused on the iPP-FS fiber production. Introduction of the nanofiller enhanced thermal stability and mechanical properties of the nanocomposite. Elastic modulus at draw ratio 10 increased from 5.3 GPa for neat iPP up to 7.5 – 8.6 GPa for compositions with 0.25 – 0.5% vol. Together with this improvement enhancement in strength at break and maintaining deformation at break were observed. Moreover, isothermal creep tests evidenced improvement in the creep stability due to the FS introduction, over the whole range of investigated draw ratios.
iii. The last results of recent research dedicated to the polypropylene kaolinite (PP-K) nanocomposites are reported in Appendix 1. Nanocomposite fibers were successfully spun up to draw ratio (DR) 15 at very high nanofiller content up to 30% wt. The presence of kaolinite not only increased the thermal stability but also enhanced elastic modulus up to 5.6 GPa – 7.0 GPa for compositions with 1% up to 30% wt. of kaolinite, in comparison to 5.4 GPa for neat PP at draw ratio 10. Moreover, for the composition with 10% wt. of kaolinite better drawability with maximum modulus was obtained in comparison to neat PP.
Finally the most important observation made on polyolefin nanocomposites fibers were summarized in the Chapter VI. It can be concluded that polyolefin fibers nanocomposites were successfully prepared by two different processing conditions: melt compounding and melt spinning followed by hot drawing.
In case of plates the introduction of nanosilica remarkably improved the thermal stability and elastic modulus, with retention of the pristine tensile properties at break. Nanocomposites fibers showed a higher improvement of the elastic modulus with respect to the nanocomposites plates containing the same percentage of nanofiller. Moreover, the introduction of the nanofiller enhanced tensile dynamic mechanical properties especially for higher draw ratio. Similar behavior was also observed in case of creep compliance. Higher creep stability was observed for the drawn fibers with nanofiller in comparison to neat polymer. This behavior could be a consequence of the different orientation and morphology related to the crystallinity developed in the spinning. These results confirmed that polyolefin containing nanofiller could be easily spun into nanofilled fiber. TEM images revealed how the experienced improvements of the mechanical properties could be probably related to the orientation of nanofiller aggregates along the strain direction and to the consequent increase of the filler-matrix interfacial area
Fabrication of n-type porous silicon membranes for sensing applications
No full textIn this work we have proposed a PSi based flow through bio-sensor able to perform fast and sensitive real time analysis. The present work is summarized as:
1. We have presented a simple fabrication method for n-type PSi free-standing membranes with straight and smooth pores of up to ~100nm of diameter.
2. A two solution method is presented to fabricate free standing porous membranes.
3. Our process maintains a very good planarity of the interface as demonstrated by the fabrication of very thin and large area free standing membranes. No HF concentration
gradient effect is noticed.
4. We found that membranes detachment does not require a high current burst but it is a self-limited process that involves a thin transitional layer at the bottom of the porous region.
5. Covalent functionalization of silicon surface is found to be suitable used to stabilize the porous surface and to act as intermediate layer for binding of other bio-molecules.
6. Role of non-specific binding in sensing efficiency is analyzed by comparing flow over and flow-through sensing for sensor fabricated on silicon substrate and sensor in freestanding nature.
7. Real time sensitivity per unit length of 0.0053degree/NaCl% and 0.0148degree/NaCl% was observed respectively for porous alumina and PSi membranes and PSi was found more suitable and sensitive for bio-sensing applications
Food Web Simulation Studies on Aquatic Ecosystems
No full textThere is an increasing interest in dynamical food web modeling, and recent advances of computational biology provide new algorithms and tools for modern systems ecology.
In this work stochastic individual-based models are used for simulating food web dynamics in two case studies: the Kelian river, in Borneo, Indonesia and a marine ecosystem in Gulf of Guinea. The two cases present effects from human perturbations. In both cases, we constructed food webs, based on real databases. We parameterized the stochastic dynamical model for the system models and performed sensitivity analysis (and community response indicators) in order to quantify the relative importance of system components.
The main aims are to understand the importance of functional diversity of aquatic ecosystems and relations between the dynamics of species and the whole community in perturbed ecosystems due to human activities (pollution due to gold mining activity and human settlements in the case of the Kelian river ecosystem and the impact of Fish Aggregation Devices on skipjack tuna communities in the case of the Gulf of Guinea ecosystem).
In Kelian river case, our results suggest that invertebrate shredders are indicators of human impact on the river. In downstream sites our results show that the river is more polluted and the relative importance of grazers and shredders decrease. The primary producers disappear downstream as consequence of mine activity and human waste.
In the marine system case study, we analyzed the effects of association between tunas and FADs, and compared this to the behavior of free tuna individuals. The results suggest that skipjack tuna is affected by the use of FADs as fishing strategy on them. Some individual species show more sensibility to variation of population size of tuna.
These two studies contribute to better understand how functional diversity is related to human impact. This kind of approach may help in shaping systems-based conservation and marine fisheries management strategies.
Keywords: food web, aquatic ecosystems, stochastic model,
sensitivity analysi