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Use of multivariate discriminant methodologies in the analysis of phenotypic and genomic data of cattle
Full text linkThe present thesis is organized in 4 main chapters.
The Chapter 1 is the general introduction and it regards the use of the multivariate statistical techniques in animal science, with a particular emphasis on the discriminant analysis.
In Chapter 2, a new statistical method called Discriminant Association Method (DAM) was proposed. The DAM approach, developed by using multivariate statistical techniques, overcomes most of problems that affect the single SNP regression technique used in the ordinary GWAS.
In Chapter 3, a new index to evaluate feed efficiency was defined: the residual concentrate intake (RCI). RCI identifies efficient and inefficient bovines in converting the concentrate. RCI can be quite simply evaluated and, in consequence, it could be easily included in genomic breeding programs. In the present research, the DAM method was applied to develop a GWAS for selecting markers associated to RCI.
The research reported in Chapter 4 was aimed to develop an algorithm able to early identify highly persistent lactations. Four different models were fitted to individual lactations by using the first 90, 120 and 150 days in milking. Two multivariate statistical techniques were exploited: the canonical discriminant analysis (CDA) and the discriminant analysis (DA). The proposed algorithm combines the talent of curve models in depict features of the lactation and the ability of multivariate statistical techniques in distinguishing differences between groups
Carcere e salute: un’indagine sulla sanità penitenziaria tra Sardegna e Lombardia
Full text linkObiettivo del presente lavoro è quello di ricostruire l’implementazione della disciplina sul passaggio di competenze nella sanità penitenziaria attraverso la percezione che di essa hanno gli operatori sanitari coinvolti nell’erogazione di prestazioni sanitarie in carcere. In tal modo non pretendiamo certo colmare le lacune della ricerca sociologica sul tema. Più semplicemente intendiamo fornire qualche spunto conoscitivo in più, attraverso il filtro di professionisti che si collocano in una via mediana tra l’interno e l’esterno dell’istituzione (Sarzotti 2007). Proprio questa ambivalenza del personale sanitario rende, a nostro avviso, particolarmente interessanti la sua analisi del contesto carcerario e il potenziale innovativo racchiuso nel suo operato.
La ricerca ha ad oggetto l’implementazione della riforma sulla sanità penitenziaria, e di conseguenza il livello di tutela della salute garantito, secondo la percezione che di essa hanno gli operatori sanitari. In effetti crediamo che la degradazione del diritto alla salute in carcere (Baccaro 2003), causata dall’afflittività della detenzione e acuita dalla marginalità sociale della popolazione reclusa, imponga al ricercatore di valorizzare costantemente la portata dinamica dello stesso. Preso atto che, a livello sostanziale, il benessere della popolazione detenuta viene garantito in maniera residuale riteniamo necessario concentrarci sulla tutela concreta dello stesso. Crediamo in effetti che, con tutte le criticità insite nell’affrontare questo tema, non si possa perdere di vista il fatto che la salute, seppur compressa, rappresenti il presupposto per l’esplicarsi di un tentativo di umanizzazione della pena (Esposito 2007)
Permanent effects of starch and fiber supplid during uterine and postnatal life on first lactation performance of dairy sheep
Full text linkThis Thesis shows the lactation performances of sheep exposed to different dietary carbohydrates during uterine life, growing and mid lactation.
The first Chapter is a literature overview of dietary carbohydrates, nutrient partitioning in lactating sheep, physiological mechanisms of insulin resistance and basis of fetal programming.
The experimental hypothesis: early exposure to dietary starch or fiber might induce permanent changes of glucose metabolism increasing lactation persistency of first lactating sheep.
The second Chapter described the experimental design.
The third Chapter presented the lactation performances of primiparous sheep fed different carbohydrates (starch and fiber) in mid lactation. Dietary treatments did not significantly affect sheep performance.
The fourth Chapter described effects of starch and fiber supplied during: 1) uterine life, 2) growing and 3) mid lactation on sheep lactation performances. Results showed that sheep exposed to starch early in life, fed fiber diets in mid lactation, had higher lactation persistency. This effect was statistically significant only for a small group of sheep in homogenous physiological status.
The fifth Chapter showed results of glucose and insulin tolerance tests performed in pregnancy and lactation. Observed patterns indicated that early in life exposure to starch might induce higher insulin resistance whereas exposure to fiber might induce higher insulin sensitivity.
Finally, general conclusions close the dissertation
Elastografia epatica: metodiche a confronto
Full text linkBackground: The cirrhotic process of liver injury is the end-stage of hepatic fibrosis, which results from progressive accumulation of extracellular matrix during the wound-healing response of the liver to repeated injury.
Mortality and morbidity rates increase exponentially once cirrhosis develops. Therefore, a prompt assessment of the degree of severity of fibrosis, an accurate and timely diagnosis of liver cirrhosis and management of complications are important in guiding therapy management in chronic liver disease. Liver biopsy is often required, but it is an invasive procedure, with a risk of severe complications (1/4000–10,000). In addition, its accuracy is prone to sampling error (6) and inter-and/or intra-observer diagnostic discrepancies occur in up to 10–20% of liver biopsies. For this reason, there is increasing interest in non-invasive methods for detecting liver fibrosis.
Ultrasound-based transient elastography (TE) is one of the first non-invasive imaging methods to be used in common practice. The technique is based on low-frequency vibrations: shear waves produced by the ultrasound machine propagate through the tissue and produce an elastic deformation, with the premise that liver stiffness (LS) measurements reflect the degree of hepatic fibrosis. Displacement is reflected in the variation of the acquired echo signals. The Siemens-based ARFI system and Philips Elast PQTM use conventional US to generate a shear wave directly within the liver tissues. This allows the sonographer to obtain both conventional US images and also specify a region of interest (ROI) for estimation of liver stiffness. The propagation velocity of the shear wave is reported in metres per second, and correlates with liver stiffness. The direct generation of shear wave within the liver tissue holds advantages over TE since it is not subject to chest/abdominal wall distortion of the waves.
Results: 110 consecutive patients with liver disease underwent a liver biopsy and liver stiffness assessment by Philips EPIQ 7TM ultrasound system, Siemens Acuson (ARFI) ultrasound system, 2 and Echosens FibroscanTM (currently the best-validated technique). The results of these three imaging techniques were compared with histological results.
A direct, strong correlation was observed between LS values assessed by TE elastography by Elast PQ and Virtual Touch (p < 0.0001) and Metavir score
Hepatitis E in Italy: a silent presence
Full text linkHepatitis E virus (HEV) was discovered in the 1980s and has been considered as being confined to developing countries. The purpose of this critical review was to determine the reported HEV seroprevalence rates in Italy, to identify predisposing factors and individuals at risk and to assess possible importation of HEV by immigrants. A critical review of 159 articles published in PubMed from 1994 to date was done. Only 27 original reports of 50 or more subjects, written in the English or Italian language, were included. Over three decades, the HEV seroprevalence varied from 0.12% to 49%, with the highest rates being reported from the central region of Italy. Risk factors included ingestion of raw pork or potentially contaminated food. The seroprevalence among immigrants ranged from 15.3% to 19.7% in Apulia. Italy has a population of 60656000; the total number of individuals surveyed was only 21.882 (0.036%). A national epidemiological survey program is needed to capture more comprehensive seroprevalence data
Influenza delle condizioni pedoclimatiche sulla selezione di caratteri funzionali nella struttura anatomica di <i>Olea europaea</i> L.
Full text linkThe olive tree (Olea europaea L.) spread from Near-East to western Mediterranean basin and cultivated varieties were multilocally selected. Morphological traits, which could have been adapted to the climate condition, could have been later influenced by human selection. Several morphological traits of wild-type and olive cultivar trees were analysed to understand which traits have been influenced by human selection. Those traits that showed significative differences have been correlated to climate data to understand how climate influenced wild olive morphology. Strong correlation has been observed among leaf traits and among ramification traits, but those were not strongly correlated to climate data. Principal component analysis shows that some components could explain a large percentage of variance. Multiple regressions show which climate data seem to be more effective in explaining wild olive morphology differences. Some climate data seem to explain differences in wild olive morphology, but wider studies on a bigger collection are needed to better understand the effect of climate on olive characters
La Continuità territoriale marittima della Sardegna nell'Unione europea
Full text linkThis thesis assesses the current EU regulatory framework to be followed by Member States when imposing and financing public service obligations in maritime cabotage to, from and between islands. The liberalisation of maritime transport services (Regulation (EEC) N. 3577/1992) has allowed EU countries to impose public service obligations or conclude public service contracts in order to maintain adequate island cabotage. Compensations for the costs of providing public service must comply with EU State aid rules as interpreted by the Court of Justice (The Altmark criteria) and by the Commission in its package of rules on services of general economic interest (The Almunia package). Drawing on examples from Spain, the United Kingdom (Scotland) and France, the research addresses the issue of providing regular maritime transport services between mainland Italy and Sardinia. The privatisation of the former State-owned maritime holding Tirrenia and its subsidiary undertakings was not accompanied by a comprehensive national regulation, leaving room for uncertainty and triggering a formal investigation procedure by the Commission. Meanwhile, public support granted by the Region of Sardinia to the maritime company Saremar was found incompatible with EU State aid rules. Taking account of the most recent legislative proposals, the study discusses the major questions to be dealt with to achieve an effective maritime territorial continuity
Invasive alien aquatic plants in South American inland waters: Inventory, prioritisation and distribution models
Full text linkBiological invasions are a widespread process at the global level and can alter population dynamics, community structure and ecosystem services in the invaded range. Aquatic plants are very often particularly invasive, especially in areas that are modified by humans. Taking into consideration the little information available, it was considered essential proposed an inventory of South American native and non-native aquatic plant species, aiming to collect information on their status of invasion, identifying the major current and the potential future plant invaders. To this aim, all the available information was collected from literature, the GBIF database and according to expert opinion. To evaluate the invasiveness of a group of aquatic plant species in South America, a standard risk assessment scheme (USAqWRA) was applied. Finally, the inventory data was used to apply a model to assess the current potential distribution of South American invasive aquatic plants. As it can be expected, considering the large number of species and diverse habitats of the investigated Continent, despite the progress herewith presented, many fundamental questions in biological invasions in South American inland waters remain unresolved. I think that the opportunity provided by establishing Global Networks for Invasion Science are a very powerful approach with plenty of benefits, increasing the capacity to identify and assess emerging invasion risks and global trends
“Volan ausel’ per air di straine guise”: gli animali come immagini del fare poetico nella poesia del Duecento e in Dante
Full text linkThe present work focuses on the observation and the study of animal figures as metapoetical meanings that we find in the similies, the metaphors and the transumptiones of the Italian poetry of the XIII century and in Dante’s corpus. Starting from the XII century, indeed, animals began to appear in the Romanic lyric production as metaphors of rhetorical, stylistic and poetical conceptions. Trough animal images, poets could express either their ideas about poetry or about the compositive methods of other writers or even about the rules of a particular literary genre. Considering the interpretative categories of Medieval zoological symbolism, the analysis of the specifical occurrences and of the intertextual relations interowen trough these animal figures, the author provides a wide range of the meanings of a specific animal image and of its metaliteral implications. The section “For a metaliteral bestiary” presents and gives a syntetical comment on the most common animal figures of the Italian poetry of the XIII century: the hypernym of bird, the swan, the nightingale, the crow and the lark. The section “Metapoetical animals in the Commedia”, on the other hand, focuses on the interpretation of the metapoetical animal figures present in Dante’s poem such as the hen, the snake, the starling, the crane, the dove and the eagle
Oxytetracycline residues from spiked ovine milk to cheese: technological implications
Full text linkAntibiotics are used in livestock, in order to ensure the health of producing-food animals. Their wide use can cause an undesirable presence of residues in milk and milk products, representing a risk for human health. To guarantee the safety of consumers, the Commission Regulation (EU) 37/2010 states the Maximum Residue Limit (MRL) of pharmacologically active substances in foodstuffs of animal origin, included milk, but no limits are specified for cheese. In addition, residues in milk can have negative technological effects during the manufacturing of dairy products. Oxytetracycline (OTC) is one of the most used veterinary antibiotics in Sardinia, due to its effectiveness and low cost. The aim of this PhD thesis was to study the distribution, between cheese and whey, of OTC added in ovine milk at MRL level, and to verify technological effects during the cheese-making process. The first part of thesis was a preliminary investigation conducted by lab cheese-making method. In the second part were conducted experimental cheese-makings from whole raw milk spiked at MRL level, to understand the partition of molecule and to evaluate technological effects during the manufacturing and ripening. In the third and fourth parts were performed experimental cheese-makings from whole thermised milk spiked at half and MRL levels, to assess the influence of the thermisation on the recovery and partition of OTC, and to understand the effect of residues on the starter culture development