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Dynamics of terricolous alpine lichen communities of the Alps and Mediterranean Mountains in a climate change perspective
Get PDFThis thesis focuses on the impact of climate change in alpine ecosystems stressing the response of high elevation terricolous lichen communities. In fact, despite the strong sensitivity of cryptogams to changes in climatic factors, information is still scanty.We collected records in 154 plots placed in the summit area of the Majella Massif. In Following a multitaxon approach, Chapter 1 includes cryptogams and vascular plants. We analysed patterns in species richness, beta diversity and functional composition. In Chapter 2, we analysed the relationships between climatic variables and phylogenetic diversity and structure indices. Chapter 3 provides a long-term response relative to the consequences of climate change on a representative terricolous lichen genus across the Alps. Chapter 4 explores the relationships between the species richness and the functional composition of lichen growing on two types of substrates (carbonatic and siliceous soils) along different elevation gradients in the Eastern Alps. Climate change could affect cryptogams and lichens much more than vascular plants in Mediterranean mountains. Contrasting species-climate and traits-climate relationships were found between lichens and bryophytes, suggesting that each group may be sensitive to different components of climate change. Ongoing climate change may also lead to a loss of genetic diversity at high elevation ranges in the Mediterranean mountains, pauperising the life history richness of lichens. Alpine results forecasted that moderate range loss dynamics will occur at low elevation and in peripheral areas of the alpine chain. Results also support the view that range dynamics could be associated with functional traits mainly related to water-use strategies, dispersal, and establishment ability. We also highlighted the importance of substrates as a main driver of both species’ richness and functional traits composition. A “trade-off” also occurs between stress tolerance and the competitive response of communities of terricolous lichens that grow above siliceous and carbonatic soils
Microbiome and resitome and foods of animal origin
Get PDFTo ensure food safety and to prevent food-borne illnesses, rapid and accurate detection of pathogenic agents is essential. It has already been demonstrated that shotgun metagenomic sequencing can be used to detect pathogens and their antibiotic resistance genes in food. In the studies presented in this thesis, the application shotgun metagenomic sequencing has been applied to investigate both the microbiome and resistome of foods of animal origin in order to assess advantages and disadvantages of shotgun metagenomic sequencing in comparison to the cultural methods. In the first study, it has been shown that shotgun metagenomics can be applied to detect microorganisms experimentally spiked in cold-smoked salmon. Nevertheless, a direct correlation between cell concentration of each spiked microorganism and number of corresponding reads cannot be established yet. In the second and third studies, the microbiomes and resistomes characterizing caeca and the corresponding carcasses of the birds reared in the conventional and antibiotic free farms were compared. The results highlighted the need to reduce sources of microbial contamination and antimicrobial resistance not only at the farm level but also at the post-harvest one. In the fourth study, it has been demonstrated that testing a single aliquot of a food homogenate is representative of the whole homogenate because biological replicates displayed overlapping taxonomic and functional composition. All in all, the results obtained confirmed that the application of shotgun metagenomic sequencing represents a powerful tool that can be used in the identification of both spoilage and pathogenic microorganism, and their resistome in foods of animal origin. However, a robust relationship between sequence read abundance and concentration of colony-forming unit must be still established
Human's movement in plague times: anthropological and documentary study of the deceasedes in the Lazzaretto Vecchio in Venice (15th-17th century).
Get PDFFondato nel 1423 per decisione del Maggior Consiglio di Venezia, il Lazzaretto Vecchio, è la prima struttura permanente in Europa destinata al ricovero degli ammalati di peste e alla quarantena preventiva di coloro che erano entrati in contatto con infetti o che provenivano da zone epidemiche. Questo studio si pone come obiettivo quello di analizzare antropologicamente una parte dei resti umani rinvenuti e comparare i risultati ottenuti con le fonti edite riguardanti la composizione dei ricoverati all’interno della struttura.
Sono stati selezionati 110 individui provenienti da 9 comuni appartenenti a due diversi archi cronologici, il 1575-1577 e il 1630-1631. Gli individui sono stati sottoposti a diverse analisi antropologiche tradizionali e indagini più dettagliate di stampo biomolecolare. Parallelamente, è stata vagliata la letteratura prodotta da studi popolazionistici editi. Le analisi antropologiche hanno rivelato un quadro popolazionistico con normale presenza di maschi e femmine, e attestazione di tutte le classi di età, dagli 0 agli oltre 50 anni. Le analisi chimico-fisiche hanno rivelato la presenza di sette individui non locali. Con riguardo all’alimentazione non vi sono particolari differenze in termini di periodi cronologici o di sesso degli individui, quanto invece si possono individuare schemi relativi alla qualità del cibo ingerito in relazione all’inserimento nel mondo del lavoro.
Per quanto riguarda le indagini di carattere documentale, nonostante alcuni degli studi popolazionistici individuati non siano considerabili recenti, ci forniscono un quadro dell’andamento della popolazione a Venezia a partire dal 1500 fino al 1700, coprendo in questo modo le cronologie d’interesse del progetto, legate agli episodi di maggiore mortalità della peste. Si riscontra una sostanziale coerenza tra i dati riportati nei diversi resoconti e la sex ratio e le fasce di età alla morte riscontrate, anche se non mancano casi specifici di forte discostamento tra i dati.Founded in 1423 by decision of the Greater Council of Venice, the Lazzaretto Vecchio is the first permanent structure in Europe intended for the hospitalization of plague patients and for the preventive quarantine of those who had come into contact with the infected or who came from epidemic areas.
This study aims to anthropologically analyze a part of the human remains found and compare the results obtained with the published sources regarding the composition of the patients inside the.
110 individuals from 9 multiple graves belonging to two different chronological arches, 1575-1577 and 1630-1631, were selected. Individuals were analyzed with traditional anthropological methods and more detailed biomolecular investigations. In parallel, the literature produced by published population studies was screened.
Anthropological analyses revealed a normal presence of males and females, and attestation of all age groups, from 0 to over 50 years.
Physico-chemical analyzes revealed the presence of seven non-local individuals. Regarding the nutrition, there are no particular differences in terms of chronological periods or of the sex of individuals, as instead it is possible to identify patterns relating to the quality of the food ingested in relation to beginning of working.
Regarding the documentary investigations, although some of the clinical studies identified are not considered recent, it provides us with a picture of the population trend in Venice from 1500 to 1700, thus covering the categories of interest of the project , linked to the episodes of greater mortality of the plague. There is substantial consistency between the data required in the various reports and the sex ratio and death ranges found, even if there are specific cases of strong discrepancies between the data
Appropriate technologies and natural systems for wastewater treatment in low- and middle-income countries
Get PDFWastewater management is an environmental and social burden that primarily affects populations in Low- and Middle-Income Countries and the global environment. Wastewater collection, treatment, and reuse have become urgent, especially considering that 80% of the world's wastewater is untreated or improperly treated and discharged directly into water bodies.
In recent years, the role of wastewater treatment plants in a sustainable water cycle has become even more critical, as they are the final destination of the collected wastewater. Indeed, the management of wastewater treatment plants should play an essential role in achieving SDG target 6.3 of the United Nations 2030 Agenda for SD. In this context, water reuse, especially wastewater reuse, plays a key role.
This research focuses on investigating the valorization of wastewater resources applying Appropriate Technologies and Natural Systems for wastewater treatment in two different Low- and Middle-Income Countries, the Palestinian Territories and Sub-Saharan Africa. The research objectives are: (1) Determine the characteristics and quality of wastewater in the two case studies analysed. (2) Identify Appropriate Technology to be used in the Palestinian Territories to treat wastewater for reuse in agriculture. (3) Assess the environmental, economic, and social impacts of this project. (4) Assess the feasibility of using natural wetlands for household wastewater treatment in Sub-Saharan region.
The first study, conducted in Rafah, Gaza Strip, showed that implementing existing primary treatment plant with a natural secondary treatment plant properly optimized the wastewater quality for reuse in agriculture and was suitable for the study area.
The second case study was conducted in Cape Coast, Ghana. It shows that the natural wetland studied is currently overly polluted and threatened by various anthropogenic factors that cannot remove pollutants from the incoming domestic wastewater. Therefore, some recommendations were made in order to improve the efficiency of this natural wetland
Genes involved in germline regulative pathways in metazoa: an integrative approach to investigate a key feature of animal biology
Get PDFIn Metazoa, the germline represents the cell lineage devoted to transmission of genetic heredity across generations. Its functions intuitively evoke the crucial roles that it plays in the development of a new organism and in the evolution of the species. Germline establishment is tightly tied to animal multicellularity itself, in which the complex differentiation of cell lineages is favoured by the confinement of totipotency in specific cell populations. In the present thesis, I addressed the subject of germline characterization in animals through different approaches, in an attempt to cover different sides and scales.
First, I investigated the extent and nature of shared differentially transcribed molecular factors in 10 different species germline-related lineages. I observed that newly evolved genes are less likely to be involved in germline-related mechanisms and that the mostly shared transcriptional signal across the species considered was the upregulation of genes associated to proper DNA replication, instead of the expected transcriptional and post-transcriptional regulation, that apparently have a higher level of lineage-specificity.
I then focused on the evolutionary history of Tudor domain containing proteins, a gene family that underwent germline-associated expansions in animals. Using data from 24 holozoan phyla, I could confirm the previously proposed evolution of the Tudor domain secondary structure. Also, I associated lineage-specific family reductions and expansions to peculiar genomic dynamics and to the evolution of germline-associated piRNA pathway of retrotransposon silencing.
Lastly, I characterized and investigated the expression of the Tudor protein TDRD7 in the clam Ruditapes philippinarum. Through immunolocalization, I could compare its expression profiles in gametogenic specimens to the previously characterized germline marker vasa. Combining results with literature, I proposed that, in this species, TDRD7 is involved in the assembly of germ granules, i.e. cytoplasmic structures associated to germline differentiation in virtually all animals, but whose assemblers can be taxon specific
Molecular modelling of organic functional materials
Get PDFThe investigation of the mechanisms lying behind the (photo-)chemical processes is fundamental to address and improve the design of new organic functional materials.
In many cases, dynamics simulations represent the only tool to capture the system properties emerging from complex interactions between many molecules.
Despite the outstanding progresses in calculation power, the only way to carry out such computational studies is to introduce several approximations with respect to a fully quantum mechanical (QM) description.
This thesis presents an approach that combines QM calculations with a classical Molecular Dynamics (MD) approach by means of accurate QM-derived force fields.
It is based on a careful selection of the most relevant molecular degrees of freedom, whose potential energy surface is calculated at QM level and reproduced by the analytic functions of the force field, as well as by an accurate tuning of the approximations introduced in the model of the process to be simulated.
This is made possible by some tools developed purposely, that allow to obtain and test the FF parameters through comparison with the QM frequencies and normal modes.
These tools were applied in the modelling of three processes: the npi* photoisomerisation of azobenzene, where the FF description was extended to the excited state too and the non-adiabatic events were treated stochastically with Tully fewest switching algorithm; the charge separation in donors-acceptors bulk heterojunction organic solar cells, where a tight-binding Hamiltonian was carefully parametrised and solved by means of a code, also written specifically; the effect of the protonation state on the photoisomerisation quantum yield of the aryl-azoimidazolium unit of the axle molecule of a rotaxane molecular shuttle.
In each case, the QM-based MD models that were specifically developed gave noteworthy information about the investigated phenomena, proving to be a fundamental key for a deeper comprehension of several experimental evidences
Design of low-power analog circuits for wake-up radio in IoT nodes
Get PDFThe goal of this Ph.D. research activity is the design of an Analog Front End which receives OOK-modulated input signals with RF carrier frequencies in the Sub-GHz ISM band and has a power consumption in the order of nanoWatts, thus targeting medium range IoT applications, i.e. with a wake-up distance within 100 meters.
Over the course of this Ph.D. activity, three prototypes have been designed using a 90-nm STMicroelectronics technology. The main challenge this topic poses is the sensitivity-power trade-off, that is a longer wake-up distance requires a higher power consumption.
All proposed implementations are clockless and leverage the second-order non-linearities of a MOSFET in subthreshold for envelope extraction. The first and second prototypes include an active Envelope Detector, a band-pass and a low-pass one, respectively, whereas the third prototype implements a passive Envelope Detector.
The first two prototypes have been tested while the third one is currently under fabrication. Measurements on the first prototype have yielded a -46-dBm sensitivity at 771 MHz with a 36-nW power consumption over a 1.2-V supply and a 2-kbit/s bitrate, resulting in 106.9-dB Figure of Merit. Measurements on the second one have yielded a projected -52.3-dBm sensitivity at 433 MHz with a 12.9-nW power consumption over a 0.6-V supply and a 1-kbit/s bitrate, resulting in 116.2-dB Figure of Merit. Simulations of the third one have yielded a -63.1-dBm estimated sensitivity at 433 MHz with a 16.8-nW power consumption over a 0.6-V supply and a 0.5-kbit/s bitrate, resulting in 124.3-dB Figure of Merit
Typed behavioural equivalences in the Pi-Calculus
Get PDFIn this thesis, I study the notion of program equivalences, i.e. proving that two programs can be used interchangeably without altering the overall observable behaviour. This definition is highly dependent on the contexts in which these programs can be used; does the context have exceptions, parallelism, etc... So proofs also need to be adapted according to the expressiveness of those contexts. This thesis presents on the pi-calculus – a concurrent programming language – under various typing constraints. Types allows us to impose different disciplines like forcing a sequential execution, or ensuring linearity, meaning an object can be used once. In each case, the bisimulation, a standard proof technique for the pi-calculus, needs to be adapted accordingly to obtain a suitable equivalence. We then test how using the modified bisimulations can be used to reason about a language with higher-order functions and references, which once translated into the pi-calculus satisfies the typing constraints
Cheering the soul: Ibn Qāḍī Baʿlabakk’s Mufarriḥ an-Nafs. Arabic edition, english translation, study and glossaries
No full textThe Mufarriḥ an-nafs (Soul-Cheerer), attributed to Badr ad-Dīn Muẓaffar Ibn Qāḍī Baʿlabakk, who served under the Ayyubids as the Chief Medical Officer of Damascus in the mid-13th century, was written as a comprehensive guide for physicians outlining different approaches to cheering the soul. The tractate is divided into ten chapters, which explore the nature of the soul, its distinction to the body as well as their connection through sensorial perception. Ibn Qāḍī Baʿlabakk distinguishes the bodily senses – hearing, vision, smell, taste, touch – and the inner senses, which he sees as stimulated through activities such as hunting and engagement in poetry and the sciences. The seventh chapter of the Mufarriḥ an-nafs includes an extended encyclopedia on materia medica as well as dispensatory of simple and compound drugs, which is devoted to treating the soul and remains unparalleled in the history of Islamicate medicine.
My doctoral dissertation offers a complete recension and translation of the Mufarriḥ an-nafs based on a stemma codicum drawn from the seventeen extant text witnesses. The dissertation contextualizes the work, its author as well as sources, and features a text commentary that seeks to enable the reader to easily place and understand the Mufarriḥ an-nafs within the tradition of Galenic medicine. The glossaries on materia medica found at the end of the dissertation are aimed at facilitating access to the pharmacological dispensatory included in the seventh chapter
Smartphone-based analytical devices with optical detection for on-site biosensing: environmental, food and forensic applications
Get PDFThere has been an increasing demand for fast and easy monitoring technologies designed to respond to different analytes. The standard analytical techniques offer accurate and precise results; however, they require clean samples, sophisticated equipment and skilled personnel. For these reasons, they are not suitable for on site, real-time, cost-effective routine monitoring. Biosensors are analytical devices integrating a biological recognition element and a transducer element able to convert the biological response into an easily measurable analytical signal. These tools can easily quantify an analyte or a class of analytes of interest even in a complex matrix, like clinical or environmental samples, thanks to the specificity of the biological components and can be easily implemented in portable devices. The activity carried out during my PhD was mainly focused on the development of different portable paper-based biosensors for multianalyte detection and their implementation into portable analytical devices for point-of-care and point-of-need applications. In particular, enzymes and cells (bacteria and mammalian cell) have been exploited as biorecognition elements, in some cases even by coupling different elements in the same biosensor to increase its robustness. The final goal of biosensors developed was the application in the environmental and forensic fields, since the target analytes are organophosphorus pesticides, heavy metals and molecules with androgenic activity, including new drugs or endocrine disrupting chemicals. Moreover, different optical detection principles (chemiluminescence, bioluminescence, colorimetry) have been exploited and coupled to create an orthogonal detection, which provides more accurate results. Different portable detectors, such as coupled-charged device, smartphone cameras and silicon photomultiplier, and also benchtop laboratory instruments have been used to validate and support the developed biosensors. Several paper-based platforms have been designed and implemented with adaptors and devices fabricated using a dual-extrusion 3D printer to better adapt to the type of assay, reagents, samples and detection method