Materials for sustainable transformations in weak contexts. Water and Land: technologies for a multiscalar infrastructure

The research explores the topic of heritage between tradition and modernity, in particular water management technologies through a series of examples in different contexts of Sardinia. Through the study of that relation, the thesis provides an important item for the project of architecture in weak context where water and land are strictly related. The research has the aim to explore the multi-scalarity through that show the relationship between water and architecture, from the territorial system to the building object. The recovery of the objects in the territories could be an important way to recovery not only a building but also a territorial system

Presenza di un «Potyvirus» sul Carciofo (<i>Cynara scolymus</i> L.) in Sardegna

A latent virus of artichoke has been isolated in Sardinia (Italy). The virus causes characteristic local lesions on Gomphrena globosa L. and Chenopodium amaranticolor Coste et Reyn., and systemic symptoms on Nicotiana benthamiana Domin. and N. clevelandii Gray. In artichoke crude sap the virus has a longevity in vitro of 20-30 hours, a dilution-end point between 10-3 and 10-4 and a thermal inactivation point between 55 and 60°C. The purification of the virus has been obtained from artichoke with two cicles of differential centrifugation followed by sucrose density gradient centrifugation. The purified suspensions had an ultraviolet light (UV) ab sorption spectrum typical of the nucleoproteins with Emax = 260-262 nm; Emin = 246 nm; and a ratio E280/E260 of 0,85 which suggests a RNA content of the virus of about 5,5%. Electron microscope observation showed that negative stained partially purified virus suspensions are composed of filamentous parti cles with a normal lenght (NL) of 730 nm and a mode of the lenght distributions of 729 nm; moreover, ultrathin sections of tissue fragments from leaves of mechanically inocu1ated Nicotiana benthamiana contained cytoplasmic inclusions of the pinwheel type. In serological tube tests, partially purified virus suspensions reacted with homologous serum (titre 1 : 1024) and a serum immune to an ALV (Artichoke Latent Virus) from Bari. These results have been substantially confirmed by serological tests with the method of «antibody coating of virus parti cles » by immune electron microscopy. I t is obvious that a latent potyvirus is widespread in artichoke growing in Sardinia. However, it cannot be exc1uded the possible occurrence in artichoke plants of a latent carlavirus too

Involvement of Activating NK Cell Receptors and Their Modulation in Pathogen Immunity

Natural Killer (NK) cells are endowed with cell-structure-sensing receptors providing inhibitory protection from self-destruction (inhibitory NK receptors, iNKRs, including killer inhibitory receptors and other molecules) and rapid triggering potential leading to functional cell activation by Toll-like receptors (TLRs), cytokine receptors, and activating NK cell receptors including natural cytotoxicity receptors (NCRs, i.e., NKp46, NKp46, and NKp44). NCR and NKG2D recognize ligands on infected cells which may be endogenous or may directly bind to some structures derived from invading pathogens. In this paper, we address the known direct or indirect interactions between activating receptors and pathogens and their expression during chronic HIV and HCV infections

<i>Fusarium roseum</i> var. <i>avenaceum</i> (Sacc.) Snyd. et Hans. agente di un « marciume molle» dei frutti di pomodoro in coltura protetta

The Authors report on the results of researches about a serious soft rot of greenhouse tomato fruits recently found in Sardinia (Italy). The disease symptoms and the characters of its causal agent, identified as Fusarium roseum var. avenaceum (Sacc.) Snyd. et Hans., are described. In laboratory, the influence of temperature, pH, and several culture media on growth and sporulation of the fungus, has been investigated. Artificial infection tests on tomato showed the high pathogenicity of the fungus to fruits only, but not to other plant organs

Robustness in Fairness against Edge-level Perturbations in GNN-based Recommendation

Efforts in the recommendation community are shifting from the sole emphasis on utility to considering beyond-utility factors, such as fairness and robustness. Robustness of recommendation models is typically linked to their ability to maintain the original utility when subjected to attacks. Limited research has explored the robustness of a recommendation model in terms of fairness, e.g., the parity in performance across groups, under attack scenarios. In this paper, we aim to assess the robustness of graph-based recommender systems concerning fairness, when exposed to attacks based on edge-level perturbations. To this end, we considered four different fairness operationalizations, including both consumer and provider perspectives. Experiments on three datasets shed light on the impact of perturbations on the targeted fairness notion, uncovering key shortcomings in existing evaluation protocols for robustness. As an example, we observed perturbations affect consumer fairness on a higher extent than provider fairness, with alarming unfairness for the former. Source code: https://github.com/jackmedda/CPFairRobus

Antifungal metabolites produced by <i>Trichoderma viride</i> against <i>Sclerotium rolfsii</i>

In this comunication we report our progress regarding the isolation and characterization of new antifungal metabolites from this strain of T. viride

Indagine fitosanitaria nel comprensorio di Sarroch, Villa S. Pietro e Pula (prov. di Cagliari) in relazione all'attività di uno stabilimento petrolifero

A five-year investigation (1988-92) of the phytosanitary situation in the Sarroch, Villa S. Pietro and Pula areas, belonging to the Cagliari district, where the SARAS-oil company has been operating for a long time, was carried out. Various degrees of damage caused by fungi, bacteria, viruses, insects, acari and by abiotic agents (edaphic and climatic) were detected on trees and herbaceous plants. Investigations on possible S02 damages by means of phytosanitary observations and chemical analysis, clearly showed no noxious effects of this gas on both cultivated and spontaneous plants

GNNUERS: Fairness Explanation in GNNs for Recommendation via Counterfactual Reasoning

In recent years, personalization research has been delving into issues of explainability and fairness. While some techniques have emerged to provide post-hoc and self-explanatory individual recommendations, there is still a lack of methods aimed at uncovering unfairness in recommendation systems beyond identifying biased user and item features. This paper proposes a new algorithm, GNNUERS, which uses counterfactuals to pinpoint user unfairness explanations in terms of user-item interactions within a bi-partite graph. By perturbing the graph topology, GNNUERS reduces differences in utility between protected and unprotected demographic groups. The paper evaluates the approach using four real-world graphs from different domains and demonstrates its ability to systematically explain user unfairness in three state-of-the-art GNN-based recommendation models. This perturbed network analysis reveals insightful patterns that confirm the nature of the unfairness underlying the explanations. The source code and preprocessed datasets are available at https://github.com/jackmedda/RS-BGExplaine

Effetti della riduzione degli input di coltivazione sul girasole (<i>Helianthus annuus</i> L.) coltivato in diversi ambienti mediterranei

A two year field experiment was carried out on six different environmental sites of Middle and Southern Italy with the aim of evaluating the effects of some low input cultural techniques on yield of sunflower (Helianthus annuus L.). In each sites sunflower commerciai hybrids were sown at different dates between January to April. Normal and minimum soil tillage were included in the experimental design, and irrigation treatments were also tested in two sites. Yield response of sunflower to minimum tillage treatments did not show in most cases a significant variation in comparison with ordinary tillage methods. Early sowing enhanced or decreased sunflower performance according to the agrometeorological features of the sites. Irrigation determined a significant yield effect but in some cases water efficiency was lower in early sowing treatments. The results indicate the possibility of reducing energy input in sunflower without remarkable yield depression, by adapting cultural techniques and hybrid choice to the environmental characteristics. Due anni di sperimentazione in campo sono stati condotti in sei differenti ambienti dell'Italia Centro-Meridionale al fine di valutare la possibilità di una semplificazione della tecnica colturale in girasole. Sono stati saggiati ibridi di diversa precocità seminati in differenti epoche e sottoposti ad un diverso grado di intensificazione delle lavorazioni. In due delle unità operative (UUOO) sono stati sperimentati anche diversi trattamenti irrigui. Nella maggior parte dei casi la lavorazione ridotta non ha determinato differenze significative di resa rispetto alla tecniche tradizionali di preparazione del terreno, mettendo in evidenza la capacità del girasole di sfruttare l'effetto residuo delle lavorazioni. L'anticipo delle semine ha avuto un effetto sulle rese variabile a seconda del sito di sperimentazione, indicando che in alcuni ambienti questo accorgimento consente di utilizzare al meglio le eventuali piogge invernali e primaverili. L'eliminazione o la riduzione degli apporti irrigui ha invece determinato significative riduzioni di produzione, anche se in alcune situazioni questo effetto è risultato meno marcato con le epoche di semina anticipate. Il primo biennio di sperimentazione ha messo in evidenza che la riduzione degli input nella coltivazione del girasole sia proponibile anche dal punto di vista economico purché si adegui la scelta delle tecniche colturali e dei genotipi alle caratteristiche ambientali

Cross-Disciplinary Approaches to the Regeneration of Minor Historical Centers: The Case of Mogoro in Sardinia

In Italy, the regeneration of historic centers is a relevant issue in the theoretical debate and practice of urban planning, a discourse which usually adopts strictly constraining approaches and tools directed almost exclusively at the preservation of the traditional characters of historic build- ings, neglecting social and economic processes. In particular, the redevelopment of minor historic centers becomes a priority action for the revitalisation of marginal territories affected by the phe- nomena of depopulation and weakening of the socio-economic structure. The paper focuses on the regional context of Sardinia to investigate methods and criteria for the drafting of planning tools for the redevelopment of minor historic centers, enabling the definition and implementation of strate- gies in accordance with the objectives and guidelines of the Regional Landscape Plan. With a case study methodology applied to the historic center of Mogoro, the research discusses an innovative and interdisciplinary approach to the definition of flexible regulations to manage the urban regen- eration process