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Long-term ecological studies on phytoplankton in Mediterranean reservoirs: a case study from Sardinia (Italy)
Get PDFArtificial lakes are strategic water resources in the Mediterranean region but are one of the most vulnerable areas to the impacts of climate change, particularly to the expected significant decrease in water resources; therefore, enhancing the ability of water management to improve water quality is crucial. This study contributes to the knowledge of the long-term ecological features of Mediterranean artificial lakes based on a case study of Bidighinzu Lake in Sardinia, Italy, a warm, monomitic and hypereutrophic reservoir mainly used for drinking water. Among the different restoration actions carried out in Bidighinzu Lake to improve water quality is the reduction of nutrient loads from the watershed. To study multiannual trends of the trophic state, a long-term series (1988–2012) of both environmental variables and phytoplankton was analysed. Mann-Kendall tests revealed increasing trends for total nitrogen to total phosphorus ratios (TN:TP; significant in spring, summer, and winter) and decreasing trends for ammonium (winter and autumn), TP (all seasons), orthophosphate (spring, summer, and winter), reactive silica (autumn), and pH (summer). Among phytoplankton, significant increasing trends were assessed in biomass of Bacillariophyceae, Chlorophyceae, Dinophyceae, and Chrysophyceae. Cyanobacteria did not show a clear trend, although at the order level, Chroococcales significantly increased in summer and decreased in winter. Despite these major tendencies, the lake did not show significant improvement in its eutrophic state, probably due to an inherent resistance and the insufficient and/or not well calibrated or applied recovery actions
Spatial distribution andmultiannual trends of potentially toxic microalgae in shellfish farms along the Sardinian coast (NW Mediterranean Sea)
No full textIn this study, the geographical distribution and multiannual trends of potentially toxic harmful algal species (HAS) were analysed at 18 mussel farms in Sardinia (Italy, North-Western Mediterranean Sea) using data derived from the Sardinian Regional Monitoring Programme (1988–2012). The results showed an increasing number of potentially toxic microalgae over the study period. Alexandrium catenella and Alexandrium minutum were the most harmful species detected. From 2002 to 2009, these species caused eight paralytic shellfish poisoning-positive events which temporarily stopped commercial trade of mussels. The statistical analysis indicated that some taxa exhibited temporal increasing trends in their abundance (e.g. Pseudo-nitzschia spp.), significant decrements (e.g. Dinophysis sp.), or both increasing and decreasing significant trends (e.g. A. minutum) at different sites, indicating the necessity of further in-depth studies, especially on certain taxa. Overall, the statistical elaboration of the long-term data provided useful signals for early detection of shellfish contamination by different potentially toxic HAS in defined sites. These signals can be used to develop best management practices
Is there a role for imatinib mesylate in the treatment of eosinophilic granulomatosis with polyangiitis?
No full textEosinophilic granulomatosis with polyangiitis (EGPA) is a systemic eosinophilic vasculitis, belonging to the group of ANCA-associated vasculitides (AAV). EGPA pathogenesis is still elusive, but a potential role for IL-5 and Eotaxins mediated eosinophil activation has been reported. Imatinib mesylate, a tyrosine kinase (TK) inhibitor, is approved for the treatment of chronic myeloid leukaemia and FIP1L1/PDGFRA positive gene fusion hypereosinophilia. A potential role for imatinib in the treatment of idiopathic hypereosinophilic syndrome (HES) and AAV has been recently proposed
Dissection of genomic correlation matrices of US Holsteins using multivariate factor analysis
No full textThe aim of this study was to compare correlation matrices between direct genomic predictions for 31 traits at the genomic and chromosomal levels in US Holstein bulls. Multivariate factor analysis carried out at the genome level identified seven factors associated with conformation, longevity, yield, feet and legs, fat and protein content traits. Some differences were found at the chromosome level; variations in covariance structure on BTA 6, 14, 18 and 20 were interpreted as evidence of segregating QTL for different groups of traits. For example, milk yield and composition tended to join in a single factor on BTA 14, which is known to harbour the DGAT1 locus that affects these traits. Another example was on BTA 18, where a factor strongly correlated with sire calving ease and conformation traits was identified. It is known that in US Holstein, there is a segregating QTL on BTA18 influencing these traits. Moreover, a possible candidate gene for daughter pregnancy rate was suggested for BTA28. The methodology proposed in this study could be used to identify individual chromosomes, which have covariance structures that differ from the overall (whole genome) covariance structure. Such differences can be difficult to detect when a large number of traits are evaluated, and covariances may be affected by QTL that do not have large allele substitution effects
La Dimensione geografica della green economy: applicazioni, prospettive, sviluppo territoriale: il caso della regione Sardegna
No full textThe thesis work on the themes of the Green Economy, entitled 'Green Economy: geographical dimension
and perspectives', aims to analyze the opportunities of territorial development represented by the green
economy.
Starting from the analysis of the National, European and international literature, the thesis work puts the
green economy in relation to the EU energy policy, the Europe 2020 Strategy and cohesion policy, assessing
the coherence, support and opportunities that it will arise.
Transition into a new economic model requires also an evolution of the implementation tools and policy
evaluation. The opportunities from green economy were measured through a careful selection/construction of indicators of climate change, energy risk and energy potential, quality of life, and more traditional economic indicators. Resorting to a model of Territorial Impact Assessment (STeMA, Prezioso 2001), the thesis measure the impacts that policy choices have on the different territorial typologies of Sardinia Region.
The study evidenced that the potential of the green economy can’t be implemented indistinctly in the case
study chosen because of regional differences, social and economic in the area.</br
Renato Solmi a confronto con Th. W. Adorno e M. Horkheimer: storia intellettuale ed editoriale di una mediazione culturale
No full textThis research has as its object the figure of Renato Solmi and focuses in particular on his work as translator of Theodor W. Adorno and Max Horkheimer. The main subject of the thesis is the events that preceded and accompanied the translation of Minima Moralia and Dialectic of Enlightenment.
After drawing a short introductory framework on early Solmi’s intellectual and editorial experiences, the thesis presents an exhaustive overview of the intense confrontation that took place in Italy on the convenience of translating Adorno and focuses, in its main part, on the discussions that were the background and followed the publication of the two mentioned translations.
In addition to rebuilding on the basis of the publications of the time and subsequent studies, the polemic notes related to the cuts and the alterations that characterized the Italian versions of both works, the thesis, thanks to the consistent use of unpublished archival material, is able to shed a new, original light on some aspects of the events in question that are not minor. Particular attention was paid to the part of the thesis devoted to the reconstruction of the detailed critical investigation aimed at assessing the reliability of introduction and translation of Minima Moralia, which Stefan Burger held on behalf of Adorno shortly after the publication of the Italian edition of this work. No less important is the question of the modifications made to the text of Dialectic of Enlightenment on the occasion of the Italian translation
Effect of a sugar-free chewing gum containing Magnolia bark extract on the development of caries lesions in healthy adult volunteers: a randomized controlled intervention trial
No full textAim: The effect of magnolia bark extract (MBE) on the development of caries lesions administered daily through sugar-free chewing gum was evaluated. A randomized double-blind intervention trial was performed.
Methods: 480 subjects (mean age±40.72) were examined using ICDAS index. A self-compiled questionnaire was submitted. A caries risk profile was generated for each subject using Cariogram software. 271 subjects, presenting inclusion criteria, were enrolled and divided into three groups (blue, yellow and green): one using chewing gum containing MBE and xylitol, another group using chewing gum with xylitol but free of MBE and finally, a control group using a sugar-free chewing gum. Each subject was instructed to chew one pellet for 5 min 3 times a day for 12 months. Plaque-pH using the strip method, a clinical examination using ICDAS scores and a microbiological evaluation (CRT Bacteria) were assessed at baseline(t0), after 6 months(t1) and 12 months(t2) of chewing gum use. Data were analysed for statistically significant differences using repeated measures of ANOVA.
Results: Data on 193 subjects were calculated and the total sample showed a plaque acidogenicity and salivary concentration of bacteria at t2 significantly lower compared to baseline.
Conclusion: The Cariogram model was able to identify the caries-related factors in adults. Twelve-month use of sugar-free chewing gum showed beneficial effects on oral health, controlling plaque acidogenicity to reduce caries risk.</br
Problematiche entomologiche dell'eucalipto in Sardegna e monitoraggio del fitofago di nuova introduzione Psilla lerp (<i>Glycaspis brimblecombei</i>)
No full textFollowing the recent accidental introduction of the lerp psyllid Glycaspis brimblecombei (Moore) in Sardinia, entomological investigations on Eucalyptus were conducted during 2011-14. Field monitoring focused on the lerp psyllid G. brimblecombei (Moore), its specific parasitoid Psyllaephagus bliteus (Riek) and other phytophagous species like the Eucalyptus gall wasps Ophelimus maskelli (Ashmead) and Leptocybe invasa (Fisher and La Salle), employing yellow sticky traps to collect adults, and foliar sampling to detect preimaginal and parasitized stages of the psyllid and to assess the number of wasp galls.
G. brimblecombei is currently the main pest of Eucalyptus in Sardinia where it reaches very high infestation levels (1070 adults/trap/month). P. bliteus density showed a bimodal trend, with the highest parasitism rates recorded in May (17%) and September (52%). The maximum number of O. maskellii galls per leaf were detected in April (78) while the minimum in July (7). In the case of L. invasa, instead, the greatest percentage of affected leaves per branch was recorded in September (17%) while the lowest in July (3%).
Among other phytophagous species, Blastopsylla occidentalis, Polydrusus (Metallites) parallelus, Gonipterus sp., and Phoracantha spp. were also detected.
In addition, the impact of the red gum psyllid on the honey production during the flowering period (June-July) in 2014, was evaluated in preliminary observations including also other wild pollinators.</br
Dealing with stress: responses for a good fitness on <i>Alpine ibex</i>
No full textA disturbance that elicits allostatic individual responses in addition to that imposed by life cycle, is defined as stress. This thesis integrated behaviour and endocrinology (using fecal cortisol and testosterone metabolites) to analyse how Alpine ibex (Capra ibex) deals with environmental pressure. The level of cortisol was directly correlated with maximum temperature in summer, showing the sensitiveness of ibex to thermal stress. I demonstrated that the selective pressures have favoured a definition of the social status in advance respect to the mating season. It remained stable and affected male reproductive success. Testosterone and cortisol are correlated and they jointly reinforced the initial impulse to compete, potentiated pre-existing pattern of aggression, but they have no effects on dominance.
I then evaluated the behavioural response of ibex to changes in the landscape of fear. Ibex responded adjusting group behaviour and in particular adult males moved closer to safer areas at the expenses of a suboptimal food intake. I demonstrated, thanks to behavioural and endocrinological data, that the chemical immobilization employed to capture ibex has a reduce impact on ibex biology and it is suitable for conservation projects.
The findings of this thesis highlight the preeminent role of the environment in shaping ibex physiology and behaviour. Moreover shown the ability of the specie to efficiently respond and recover both to predictable and to unpredictable disturbance
Characterization of a wide collection of tomato (<i>Solanum lycopersicum</i> L.) for morpho-phenological, quality and resistance traits
No full textTomato (Solanum lycopersicum L.) is considered one of the leading vegetable crops worldwide and it is an important model species for plant biology, in particular for the genetic control of quantitative variation, fruit ripening processes and resistance to biotic stress. The availability of the tomato genome has enhanced the chances to unravel the genetic control of simple and complex traits that can be achieved by genome-wide association studies which exploit natural variation.
Accordingly, in the present study it has been investigated a wide collection of tomato mainly including landraces (71 from Italy of which 64 from Sardinia, and 44 from all over the world) which were compared to ten cultivars and five wild-related tomato species. Three experimental trials in two years and two locations were performed and data were collected for a) phenotypic traits by both classic and precision phenotyping, b) genetic diversity by means of 19 micro-satellite markers, c) carotenoid content and d) antixenotic resistance to Tuta absoluta (Meyrick).
Results revealed high levels of phenotypic and genetic diversity pointing to these landraces as a valuable model to identify QTLs and genes of relevant interest. Finally, the associations detected between molecular markers and phenotypic traits indicate that our collection is suitable for future association mapping and transcriptome correlation studies in addition to breeding purposes