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Renewable energy production from fuel cells and energy storage in flow batteries are becoming increasingly important in the modern energy transition. Both batteries use polyelectrolyte membranes (PEMs) to allow proton transport. In this chapter, both PEMs and PEMs-based nanocomposites have been discussed using various simulational approaches. A coarse-grained model of a Nafion film capped by the substrates with variable wettability has been used to simulate nanocomposites of PEMs by classical molecular-dynamics (MD) method. Classical MD modeling results have also been reviewed for a PEM-graphene oxide nanocomposite internal structure and dynamics. Ab-initio simulations have been implemented to describe the proton transfer pathways in anhydrous PEMs. Finally, the large-scale mesoscopic simulations have been introduced to shed light on the water domain features present in the hydrated PEMs. A brief description of polybenzimidazole membrane as electrolyte and Ionic Liquids as dopants for fuel cells is also presented.

Microbial species exhibit a wide repertoire of phenotypic responses to their surroundings, be it stresses posed by their environment, or signals from their bacterial community. Despite advances in computer vision, reporting such phenotypic responses is often done in a qualitative manner. In the course of my work I developed a user-friendly software tool to address the lack of a standardized, quantitative method to measure microbial phenotypes macroscopically. This freely available software, called Iris, can quantify a wide range of microbial phenotypes at the colony level and in a high-throughput fashion. Iris is already used by several research groups, and I present some of its diverse applications and potential for hypothesis generation. One such application is the quantification of the impact of each gene on the cell envelope permeability in E. coli. The Gram-negative bacterial cell envelope forms a barrier against antimicrobial drugs, drastically limiting the list of treatments effective against these organisms. To expand our knowledge on how this multi-layered is built and perturbed, we developed a rapid screening method to detect mutants with envelope defects. By screening a systematic gene deletion mutant collection in E. coli across 4 conditions, we identified a number of mutants with defects in envelope assembly. Among those were genes known to be involved in envelope biogenesis, as well as 102 genes of unknown function. In the course of my work I built upon and improved this screening approach, to acquire quantitative membrane permeability measurements that can be used for high- throughput chemical genomics approaches. Gram-negative bacterial envelope is both a permeability barrier, and a structural barrier. The structural component mainly consists of the rigid peptidoglycan (PG) sacculus, which gives the cells the ability to withstand both turgor pressure and environmental insults. Although biosynthesis of PG is central to bacteria and a target of β-lactam antibiotics, its regulation remains largely elusive. Recently, a number of regulators of PG biosynthesis have been identified, and shown to have coevolved with domains in PG synthases. With the aim of uncovering potential regulatory connections, I developed a computational approach to explore the coevolution of domains in proteins involved in cell wall biosynthesis and remodeling with other proteins in the cell. The method correctly identified existing regulatory interactions, and is readily applied to species across the bacterial kingdom.

Περίληψη: Η παρούσα διδακτορική διατριβή ως κεντρικό σκοπό έχει την διερεύνηση του χειρισμού του όρου τοπίο, μέσα από τις δράσεις και τις τοποθετήσεις διαφόρων κοινωνικών ομάδων από την Μεταπολίτευση μέχρι σήμερα. Στο πλαίσιο της βιβλιογραφικής έρευνας του παρόντος, -μεταξύ άλλων- επιχειρείται: α) η προσπάθεια τεκμηρίωσης μιας θεωρητικής/ιστορικής βάσης της έννοιας τοπίο, β) η διερεύνηση των διαλεκτικών σχέσεων φύση-τέχνη και πόλη-ύπαιθρος, ως κατευθυντήριες διερεύνησης της διαλεκτικής σχέσης φύση-πολιτισμός από την αρχαιότητα μέχρι σήμερα, γ) καθώς εξετάζονται και οι κυρίαρχοι λόγοι ανάδυσης της σύγχρονης συνείδησης του τοπίου στην Ελλάδα, όλα ιδωμένα υπό το πρίσμα μίας ιστοριογραφικής κριτικής, με κύριο άξονα την διεπιστημονικότητα. Με δεδομένο ότι στην κατανόηση του τοπίου συμβάλλει η θεώρηση της σχέσης φύσης-πολιτισμού, η παρούσα διδακτορική διατριβή, λαμβάνοντας ως περίπτωση μελέτης το νησί της Κρήτης, μέσω μιας πολυμεθοδολογικής προσέγγισης με πολλές διαφορετικές εποπτείες, επιχειρεί να αποκρυπτογραφήσει τις αιτίες των επικρατέστερων τάσεων της ρητορικής αλλά και της πρακτικής που αφορούν στο τοπίο, όσο και να αποσαφηνίσει τις ερμηνείες και τις παρερμηνείες που αναδύονται με την χρήση αυτού του όρου, με απώτερο σκοπό την απόδοση ενός ορθολογικού προτύπου και ει δυνατόν προσανατολισμού στο πεδίο της συλλογικότητας, με αφορμή και την Ευρωπαϊκή Σύμβαση για το Τοπίο. Summarization: The purpose of this doctoral dissertation, is to investigate the treatment of the term landscape, through the actions and attitudes of various social groups, from the Restoration of Democracy period to the present. In the framework of the bibliographic research of the current thesis, among others, is attempted: a) to document a theoretical/historical basis of the concept of landscape, b) to explore the dialectic relations between nature-art and town-countryside, as guiding elements for the onvestigation of the dialectic relation between nature and culture from the Antiquity to the present day, c) as well as to detect the prevailing reasons for the emergence of contemporary landscape consciousness in Greece, all seen in the light of a historiographical critique, based on an interdisciplinary approach. Given that the understanding of landscape contributes to the consideration of the relation between nature and culture, this doctoral thesis, taking as a case study the island of Crete through a multidimensional approach, attempts to decipher the causes of the prevailing rhetorical tendencies and practice in landscape, and to clarify the interpretations and misinterpretations that emerge using this term, with the ultimate goal of rendering a rational model in the collective field, also taking into consideration the European Landscape Convention.