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Opto-microfluidic device in Lithium Niobate to investigate the proteins synthesis
No full textMicrofluidics is an interdisciplinary research field that deals with the production and the study of droplets on a micrometric scale. In the last decades microfluidics has gained an increasing interest by the scientific community.
Microfluidics has arisen great attention since it controls the transport of small amounts of liquids inside which, for example, it is possible to make chemical reactions occur or through which is possible to transport biological samples or diagnostic markers.
Their features, in combination with fast analysis tools, allow for the realization of Lab-on-a-Chips (LOCs) that is to say miniaturized and portable devices able to perform chemical, biological, environmental or medical analyses where bulky laboratory facilities lack.
As a matter of fact in microfluidics' standards, imaging techniques are exploited to monitor the droplets generation and/or movement. In these cases, however, bulky microscopes eliminate the obtained advantages with miniaturization.
For this reason, it is important to integrate completely on a small scale the optical stage with the microfluidic one achieving a so called opto-microfluidic platform, an objective accomplished in the last few years, for example, through the realization of Lab-On-a-Chip in Lithium Niobate in the Physics and Astronomy department "Galileo Galilei", in Padua. This material has excellent optical properties that consent to host the realization of Ti-indiffused waveguides, by which it is possible to detect the produced droplets and their contents in the engraved microfluidic channel as it will be shown in this thesis.
This thesis presents a feasibility study on the use of integrated optics coupled to microfluidics circuitry to investigate the proteins synthesis.
Since the process of the protein synthesis could be difficult and require several days, it is important to save as much as possible of the biological samples, by periodically monitoring its concentration both after the final purification process, and during the subsequent experiments. However, this usually implies the use (and waste) of a significant amount of the sample, so that often a compromise between these two aspects has to been found. On the contrary, in principle the use of the opto-microfluidic approach presented in this thesis would allow to comply with both the mentioned needs, since the monitoring of the protein concentration would be realized in a fast ways and without requiring large amount of the biological samples. Moreover, it can allow to monitor the effect of each update that can be introduced to the process to improve the synthesis or add extra elements into the proteins.
The work-plan of the thesis includes the realization and validation of the opto-microfluidic platform and the application to the detection of proteins. It consists of the characterization of various experimental setups until reaching the best configuration to monitor droplets containing proteins and a reagent called Bradford through a completely integrated opto-microfluidic device in Lithium Niobate. The study is aimed at understanding how proteins' synthesis can be monitored even in small amounts as some confined in a micrometric droplet.
The thesis aims to demonstrate that, by investigating how the protein-based droplet interacts with a light beam. It will be demonstrated that depending on the measurement of the optical transmission of such a droplet it is possible to detect if and when the protein has been synthesized. The final aim of the project, this thesis is included in, is the obtainment of a qualitative proteins detector.
The presence of the proteins in the dispersed phase is evaluated by means of the transmitted light using a systematic measurement protocol and having good control on the experimental apparatus thanks to the detailed characterization.
The results obtained show that it is possible for our setup to detect qualitatively the presence of proteins in micrometric droplets
La successione giurassica di Passo Brocon (TN): caratterizzazione, interpretazione paleoambientale e confronto con il Giurassico dellâAppennino centrale
Full text linkIn this thesis I make a characterization and paleoenvironmental interpretation of the Jurassic succession cropping out at Passo Brocon (north-eastern Italy). From the geological mapping of the area, the Rosso Ammonitico Veronese Formation resulted absent. A comparison with the geometries and facies of the Jurassic units of the Umbria-Marche region (Central Apennin) has been made in order to propose a hypothesis explaining this formational gap
Angular momentum and shapes of rotating quantum droplets.
Full text linkABSTRACT:
Self-bound quantum droplets, resulting from the balance between attractive and repulsive forces
between their atomic components, appear in different physical scenarios, the prototypes being liquid
droplets made of superfluid Helium-4.
Recently, a new kind of quantum droplets have been found using a bosonic mixture of ultracold
atoms, whose stability results from the interplay between the inter-species attractive mean-field
energy and the repulsive term representing a beyond-mean-field correction due to quantum
fluctuations. Being a mixture of Bose-Einstein condensates, quantum droplets are likely superfluid.
Thus, when they are set into rotation, the angular momentum can only be stored in the form of
quantized vortices and/or capillary waves.
In the case of superfluid Helium-4, the interplay between vortices and capillary waves results in
droplet shapes surprisingly close to those of classical liquid droplets rotating with the same angular
velocity.
In the case of quantum droplets made of Bosonic mixtures, such interplay remains to be uncovered.
The scope of this thesis is to theoretically study the stability and appearance of rotating self-bound
nanodroplets made of Bosonic binary mixtures using numerical simulations based on Density
Functional Theory, to unveil the interplay between the superfluid nature of the system and their
shapes
Rings with morita duality
No full textWe present here an account of basic properties of Morita duality, which
comprehends comparison and relationships with Morita equivalence and its
characterization via linear compactness, as done by Müller. In the end, we
present in detail the work of Áhn, who showed that every commutative
linearly compact ring possesses a Morita duality
Ottimizzazione della produzione di ioni pesanti con sorgenti di tipo ECR presso LNL
Full text linkIl presente lavoro di tesi riguarda uno studio sperimentale condotto sulla sorgente di ioni di tipo ECR denominata LEGIS ed installata presso i Laboratori Nazionali di Legnaro (LNL) dell’INFN. In questo tipo di sorgenti ioni ad alto stato di carica vengono prodotti all'interno di un plasma, confinato in una camera da vuoto (detta camera del plasma) da una particolare configurazione magnetica detta a "B-minimo". Il meccanismo tramite il quale il plasma viene generato e sostenuto prende il nome di Electron Cyclotron Resonance (ECR) e consiste in un'interazione risonante tra onde elettromagnetiche veicolate dall'esterno (nel range dei GHz) ed elettroni, a fronte della quale questi acquisiscono energia sufficiente a ionizzare più volte un gas o vapori metallici precedentemente introdotti.
L'efficienza di tale meccanismo dipende dalla particolare configurazione elettromagnetica che si instaura all'interno della camera da vuoto, la quale funge da cavità risonante. La camera del plasma della sorgente LEGIS è stata recentemente modificata a seguito di studi numerici, con lo scopo di ottimizzare il processo di risonanza ECR: la verifica sperimentale dell'efficacia di tale modifica è oggetto del presente lavoro di tesi.
Questa è stata condotta ottimizzando la sorgente per la produzione dello ione 136Xe28+, tra i più richiesti dalla comunità scientifica dei LNL. Partendo da risultati ottenuti precedentemente alla modifica ed a questo lavoro di tesi, considerati come riferimento, i test sono consistiti nella corretta applicazione sperimentale della tecnica nota come “frequency tuning”, che consiste nella ricerca della frequenza ottimale di eccitazione del plasma. In questo modo è stato possibile individuare la frequenza che massimizza la produzione dello ione di interesse, pari a 14.444 GHz, che differisce da quella ottenuta tramite i calcoli teorici di poco più di 10 MHz. Inoltre, il corretto tuning della sorgente, non solo in termini di frequenza ma anche degli altri parametri coinvolti nel funzionamento ad eccetto della potenza delle microonde trasmessa al plasma, ha determinato un incremento dell'intensità estratta del 30%, risultato di assoluta rilevanza per i LNL.
Dal momento che l’ottimizzazione è stata eseguita senza variare la potenza trasmessa al plasma, a corollario di questo lavoro di tesi è stata effettuata una misura sistematica per evidenziarne l‘influenza sul funzionamento della sorgente, in particolare sulla produzione di alti stati di carica. Test effettuati ionizzando ossigeno hanno dimostrato l'esistenza di una potenza ottimale per la produzione di un particolare stato di carica (nel caso specifico pari a circa 90 W per lo ione O6+), in accordo con la teoria alla base del funzionamento delle sorgenti ECR
Optimal Control of Superconducting Qubit Gates
Full text linkQuantum technologies promise to improve the performance of a whole range of computational processes. This is why researchers have been studying the physical implementation of such technologies for over 30 years. One of the most well-established platforms to perform quantum calculations are superconducting qubits, in which Cooper pairs tunnel across insulating barriers that separate superconductors. After introducing superconductivity theory, we simulate one- and two-qubit gates by controlling applied voltages and magnetic fields. Then, we show how an external noise source can alter the behavior of the quantum gate. Finally, we apply optimal control theory to find the time-dependent voltage and magnetic fields that maximize the target gate’s success probability. With this procedure we aim to compensate for the experimental imperfections via a general numerical approach