A study of stability analysis of pyroclastic covers based on electrical resistivity measurements

Usually, the degree of stability of a slope is quantified by the Factor of Safety whose values depend on physical and mechanical soil properties analyzed on samples of much reduced sizes or referring to very small soil volumes around porous probes. To overcome the limit of punctual information, we propose a semi-empirical approach based on the use of geophysical methods and the employment of a geophysical Factor of Safety recently introduced by the authors in terms of local resistivities and slope angles. In this paper, we show an application of our proposal on a test area of about 2000 m2 on Sarno Mountains (Campania Region - Southern Italy), where shallow landslides involving pyroclastic soils periodically occur triggered by critical rainfall events. Starting from two resistivity tomography surveys performed on the test area in autumn and spring, we obtained maps of the geophysical Factor of Safety at different depths for the two seasons. We also estimated the values of the Factor of Safety by using the infinite slope model in the dry and saturated scenario. A comparison between the values of the geophysical and geotechnical Factor of Safety shows advantages and disadvantages of our approach.Comment: 16 pages, 5 figure

From collection to myco-reactor: filamentous fungi for bioremediation

Despite the water is present on Earth planet in a large amount, only a small fraction of it can beexploited by living organisms. Mankind use much more water than other living beings because, inaddition to its survival, it is used for agriculture, breeding, industry and as an energy source. Research on new and different water purification techniques is currently one of the unsolved points to reducethe human environmental footprint. In general, water or any polluted matrix can be purified with different methods (chemical, physical, biological), but none of them fully satisfies the efficiency andsustainability criteria. In the last thirty years, the research in the field of eco-friendly technologies is increasing: among thevarious purification processes, bioremediation is giving excellent results. This system aims to reducepollutants in the various environmental matrices, exploiting the metabolic capabilities of livingorganisms, such as bacteria, fungi and plants, to degrade them into simple products without usingchemical substances or expensive and complex treatment plants. The bioremediation that uses fungi for the treatment of polluted environmental matrices is called mycoremediation. Fungi are organisms suitable to be used in bioremediation processes because their metabolism allows them to grow andsurvive in the presence of toxic substances and in extreme conditions that are not tolerated by mostof the other organisms. One of the advantages of using fungi in bioremediation processes is the possibility of using them evenwhen the concentration and bioavailability of the pollutants is very low in the substrates, as in thecase of drugs for human and veterinary use dispersed in wastewater. Another advantage related to filamentous fungi - on which this thesis will focus - is their hyphal structure which greatly increasestheir distribution and colonization capacities. Several filamentous fungi are able to act on recalcitrantorganic pollutants: from chlorophenols to dioxins, from toluene to hydrocarbons. They are not alwaysable to completely degrade them, but they can at least transform them into less toxic compounds. Theability to metabolize organic compounds that are very different from each other in chemical structureis due to the low specificity of many fungal enzymes. The characteristics of the fungi are not only species specific, but often strains specific, which is why the research and identification of new strains is fundamental for mycoremediation. It is precisely fromthe experiments carried out on the strains kept in the collections and isolated from different environments such as extreme ones that new treatments can be developed. Nowadays, theenvironments that can be defined as extreme are no longer just the sea depths or Arctic glaciers, but also the production and wastewater treatment plants. Although they are ideal environments for theselection of new fungal strains, research continues to focus only on bacterial communities, leaving the fungal component practically unexplored. Another unexplored field is the application of fungal strains with known metabolic abilities in treatment plants at laboratory scale and, above all, at industrial level. A type of plant that may be suitable for filamentous fungi, of which very few examples are found in literature today, is that of aerated membrane bioreactors (MABR). This is a promising technology for the treatment of recalcitrant substances in an aqueous environment, based on the transfer of a gas (e.g. air or oxygen, but in principle also other gases can be used) across a membrane to a biofilm in contact with a liquid phase containing the substrates to be metabolized. The use of filamentous fungi in MABR is currently limited mainly to biotransformation and industrial processes for the production of enzymes and bioproducts. Thanks to the multidisciplinary research approach, carried out between the mycology laboratory (DiSTAV - Department of Earth, Environmental and Life Sciences) and that of industrial chemistry (DCCI - Department of Chemistry and Industrial Chemistry) of the University of Genoa, it was possible to study the filamentous fungi isolated from extreme environments and to apply the strains present in the mycological collection of the laboratory (ColD - Collection of DiSTAV) for the development of this type of implant. In summary, the purpose of the work was to develop, expand and test protocols in the field of mycoremediation such as MABR, with particular attention to the isolation, conservation and use of fungal strains suitable for the treatment of polluted matrices. The thesis is structured in five chapters. In the first chapter the techniques used by the mycology laboratories to isolate and identify the filamentous fungi found in extreme or polluted environments are discussed. In the second and third chapters two case studies concerning isolation and identification of filamentous fungi from landfill leachate and from different ripening stages of a composting plant are discussed, as a starting point for future applications of native strains to treat complex wastewater. In the fourth chapter the plants and the diversity of aerobic biological treatments are presented, with particular attention to the methods for supplying oxygen and substrate. The chapter concludes with the types of bioreactor developed with filamentous fungi. The last chapter describes the development of an aerated membrane bioreactor with a model filamentous fungus for future use in wastewater treatment

Study of the interaction between sialic acid-binding immunoglobulin-type lectins (Siglec) and sialylated glycans for the development of a new generation of immunomodulators.

Glycans and complementary glycan-binding proteins represent essential components in the control of both innate and adaptive immunity. Sialic acids are a family of sugars found on the terminal end of mammalian glycoconjugates; they able to act as marker of self in the immune system, as such residues are absent in most microbes. Sialic acid-binding immunoglobulin-like lectins, or Siglecs, are cell surface receptors that recognize sialic acids and are known to modulate immune responses, influencing almost every cell in the hematopoietic system. Siglecs are involved in events like cell adhesion and signaling, inhibition or regulation of the immune cell activation, all mediated by the interaction with sialylated ligands. Sialic acid-Siglec interactions have been associated with a broad spectrum of diseases, stretching from autoimmunity to neurodegeneration and cancer. Thus, strategies for a rational modulation of the interactions between Siglecs and sialylated glycans in pathophysiological processes exhibit a great therapeutic potential. In this context, the present thesis project aimed at the study of the interaction between Siglecs and their cognate sialic acid containing ligands, to disclose the key recognition events underlining host immune suppression or activation. To this end, a multidisciplinary approach combining advanced technologies as ligand-based NMR techniques, including STD-NMR and tr-NOESY, biophysical binding assays and computational methodologies, such as homology modelling docking and MD simulations, was applied to provide an atomistic depiction of the interaction interfaces between various sialoglycans and their receptors. The described strategy has been employed to characterize the binding features of several receptors of the Siglecs family, namely CD22/Siglec-2, Siglec-10 and Siglec-7. CD22 is a B-cell surface inhibitory protein capable of selectively -(2,6) linked sialylated glycans, thus dampening autoimmune responses against self-antigens. The characterization of complex-type N-glycans by CD22 allowed to describe the conformational behavior of the flexible ligands; the formation of CD22 homo-oligomers on the B-cell surface was also addressed. Furthermore, it was provided a global vision of how the most diffuse neuraminic acid forms of sialylated N-glycans are accomodated in the binding pocket of CD22. Moreover, the elucidation of the binding epitope of a synthetic sialo-mimetic upon CD22 interaction afforded new hints for the design and synthesis of high-affinity ligands of therapeutic relevance against B-cell derived malignancies. Then, the Siglec-10, an inhibitory receptor that recognize 2,3 and -linked sialoglycans was studied, thus providing the first insights of the molecular mechanisms regulating the interaction between Siglec-10 and naturally occurring sialoglycans. After that, Siglec-7, a well-established inhibitory receptor that is primarily located on natural killer where it acts as inhibitor of cancer cells cytotoxicity via sialylated ligands binding, has been characterized in the interplay with the oncogenic pathogen F. nucleatum. Indeed, the presence of sialylated lipopolysaccharide (LPS) on certain F. nucleatum strains, hinted that it may have a significant role at the immune interface. The interaction between Siglec-7 and the O-polysaccharide chain from the LPS of F. nucleatum 10953 strain has been depicted, thus delineating a structural binding model that might contribute to explain the etiological role of F. nucleatum in carcinogenesis. A similar approach was employed to other sialoglycan- related systems, i. e. to dissect the mechanism of sialic acid recognition and hydrolysis by mumps virus hemagglutinin neuraminidase, a viral glycoprotein that plays key roles in virus entry and infection; and to assess the binding of the human macrophage galactose-type lectin (MGL) in the interplay with lipooligosaccharide of E. coli strain R1. In conclusion, the structural and functional characterization of Siglec- sialylated glycans interaction have allowed the analysis, at a molecular level, of crucial feature of 3D complexes, highlighting the molecular determinants involved in recognition and binding events, that will aid for the development or optimization of molecules for therapeutic targeting of the Siglecs

L'evolució dels serveis socials a Tona (2008-2011)

La crisi econòmica que va començar al final del 2007 i la Llei de Dependència han fet incrementar en molt pocs anys, i d’una manera exponencial, les demandes als serveis socials. En aquest article es fa una repàs de la tasca d’aquests serveis i es donen a conèixer les dades de l’enorme esforç d’atenció assistencial que s’ha hagut de fer entre el 2008 i l’actualitat

Accounting for uncertainty in predictions of a marine species: Integrating population genetics to verify past distributions

We develop a new perspective on the uncertainties affecting the predictions of coastal species distributions using patterns of genetic diversity to assess the congruence of hindcasted distribution models. We model the niche of the subtidal seagrass Cymodocea nodosa, for which previous phylogeographic findings are used to contrast hypotheses for the Last Glacial Maximum (LGM) in the Mediterranean and adjacent Atlantic coastal regions. We focus on amelioration of sampling bias, and explore the influence of other sources of uncertainty such as the number of variables, Ocean General Circulation Models (OGCMs), and thresholds used. To do that, we test geographical and environmental filtering of presences, and a species-specific weighted filter related to political boundaries for background data. Contrary to our initial hypothesis that reducing sampling bias by means of geographical, environmental or background filtering would enhance predictive power and reliability of the models, none of these approaches consistently improved performance. These counter-intuitive results might be explained by the higher relative occurrence area (ROA) inherent to linear coastal study areas in relation to terrestrial regions, which may cause worse predictions and, thus, higher variability among models. We found that the Ocean General Circulation Models (OGCMs), the threshold and, to a smaller extent, the number of variables used, conditioned greatly the variability of the predictions in both accuracy and geographic range. Despite these uncertainties, all models achieved the goal of identifying long-term persistence regions (glacial refugia) where the highest genetic diversity for Cymodocea nodosa is found nowadays. However, only the CCSM corroborated the hypothesis, raised in previous studies, of a vicariant process in shaping the species' genetic structure. (C) 2017 Elsevier B.V. All rights reserved.Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) [SFRH/BPD/85040/2012]Pew Foundation (USA)[UID/Multi/04326/2013]info:eu-repo/semantics/publishedVersio

The pedagogical character of the biographical narratives in the context of approach to student-centered learning

A melhoria da formação inicial de professores, nas últimas décadas, está sendo investida de novos desafios, especialmente, tendo em conta a emergência das denominadas sociedades do conhecimento.Nas reformas para o Ensino Superior, especialmente no âmbito da constituição do Espaço Europeu do Ensino Superior, a abordagem da aprendizagem centrada nos estudantes é fulcral. Este artigo, do tipo metanalítico, tem por objetivo argumentar em favor douso das narrativas biográficas, segundo diversas perspetivas, e, especialmente, nas que centram-se na ideia da “voz do estudante” como estratégia de efetivação da abordagem de ensino centrada nos estudantes. Objetiva, ainda, discutir alguns dos desafios inerentes à implementação desta abordagem no contexto da formação inicial de professores e, a partir dessa discussão, apresentar uma perspetiva de formação que pode dar pistas de superação dos referidos desafiosLa mejoría de la formación inicial de profesores, en las últimas décadas, está siendo investida de nuevos desafíos, especialmente teniendo en cuenta la emergencia de las denominadas sociedades del conocimiento. En ese contexto emergen reformas para la Enseñanza Superior donde el abordaje del aprendizaje centrado en los estudiantes y el aprendizaje a lo largo de la vida son céntricos. Este artículo, del tipo metanalítico, tiene por objetivo argumentar en favor del uso de las narrativas biográficas, según diversas perspectivas, y especialmente, en las que se centran en la idea de la “voz del estudiante” como estrategia efectiva del abordaje de la enseñanza centrada en los estudiantes. Se centrará en la discusión de algunos de los desafíos inherentes a la implementación de este abordaje en el contexto de la formación inicial de profesores y, a partir de esa discusión, presentar una perspectiva de formación que puede dar pistas de superación de los referidos desafíosImproving teacher education in recent decades is being invested in new challenges, especially given the emergence of so-called knowledge societies. In this context emerge reforms for Higher Education where the approach to student-centered learning and lifelong learning are central. This kind of metaanalytic article aims to argue the use of biographical narratives, according to different perspectives, and especially those that focus on the idea of “student voice” as a strategy to develop the teaching approach centered, on students. Also, aims to discuss some of the challenges inherent in implementing this approach in the context of initial teacher education, and from that, bring out a perspective of training that could give clues for overcoming these challenge