MOLECULAR BASIS OF THE INNATE IMMUNE RESPONSE IN RUMINANTS: FOCUS ON ADIPOSE TISSUE

The main aim of this thesis is to explore new aspects of the innate immune response in ruminants, especially focusing on the role of adipose tissue. Particularly, adipose tissue was investigated in order to provide new information in a species where this tissue is very poorly characterised. In ruminants, fat tissues play important biological roles for animal health for quality and gain in meat and milk production as well. A specific knowledge of how these pathways are controlled is of key importance for the management of animal health and from an economical perspective. Nevertheless, existing studies are mostly carried out in humans, where obesity is a major issue and little is known about ruminants. In this thesis, the distribution of white and brown adipose tissue in several adipose deposits was investigated through UCP1 expression and general histology, showing a clear distinction between these two macroareas, with brown adipose tissue mostly present in visceral deposits. With our study, we also demonstrated the presence of brown adipose tissue in 30 days old goat kids and therefore the presence of this tissue in growing animals and not only in newborns. In addition, visceral and subcutaneous deposits were investigated with proteomic techniques, demonstrating that these two macroareas can be clearly distinguished by their proteomic profiles, but single deposits within the same macroarea do not display particular proteomic differences. Moreover, we demonstrated the involvement of adipose tissue of goat kids in inflammatory and immune response pathways, through expression of at least 27 immune related proteins, of which nine, namely ceruloplasmin, gamma fibrinogen, hemopexin, kininogen 1, lactoferrin, protein dj, thiosulfate sulfurtransferase, tumour translationally controlled 1 and valacyclovir hydrolase, were never investigated before in adipose tissue. At a later stage, we focused our attention only on visceral adipose tissue, particularly on omentum, demonstrating that maternal diets enriched with either saturated or unsaturated fatty acid influence goat kid omentum proteome, but these influence is not confirmed at mRNA expression level. In addition, no influence of the maternal diet is showed on BAT distribution in goat kids

Green vs fossil-based energy vectors: A comparative techno-economic analysis of green ammonia and LNG value chains

This study conducts a comparative techno-economic assessment on the value chains of ammonia, as a green energy vector, and Liquefied Natural Gas (LNG), representing the benchmark energy vector, for long-distance energy transportation from Middle East to Europe. The value chain involves production from resources, conversion to an energy vector, storage and transport and reconversion of the energy vector to a suitable fuel. For comparison purposes, an electric power output of 400 MW is assumed to be produced by a power plant that utilizes either green or fossil fuels delivered to it. The adopted parameter for this comparison is the Levelized Cost of Energy (LCoE). Greenhouse gas emissions are economically penalized through the Social Cost of Carbon (SCC). Considering a SCC of 0.100 euro/kg, the LCoE of the LNG value chain is 59.19 euro/MWh, while that of ammonia is 231.71 euro/MWh. Since the cost of producing green hydrogen and purified natural gas strongly affects the results, a sensitivity analysis is performed to assess the impact of the assumed values. The SCC required to break even the LCoE of the two value chains is: 0.183 euro/MWh when considering the most favorable scenario for the green energy vector (low green hydrogen and high purified natural gas production costs) and 1.731 euro/kg when considering the most unfavorable one. This study highlights the cost-effectiveness of LNG in the current economic and regulatory landscape. However, the break-even range for the SCC indicates the potential for green ammonia to gain economic viability under higher carbon pricing scenarios

Dynamic models for Large Eddy Simulation of compressible flows with a high order DG method

The impact of dynamic models for applications to LES of compressible flows is assessed in the framework of a numerical model based on high order discontinuous finite elements. The projections onto lower dimensional subspaces associated with lower degree basis functions are used as LES filter, along the lines proposed in Variational Multiscale templates. Comparisons with DNS results available in the literature for plane and constricted channel flows at Mach numbers 0.2, 0.7 and 1.5 show clearly that the dynamic models are able to improve the prediction of most key features of the flow with respect to the Smagorinsky models employed so far in a VMS-DG context

The presence of dominant follicles and corpora lutea does not perturb response to controlled ovarian stimulation in random start protocols

The advent of random start protocols to shorten the time needed to store oocytes in women with malignancies has represented an important improvement in the field of fertility preservation. However, Randomized Controlled Trials are difficult to implement in this area and available evidence that supports this approach remains modest. To shed more light on this issue, we compared the follicular development between the ovary carrying the dominant follicle or the corpus luteum and the contralateral resting ovary in 90 women who underwent random start controlled ovarian stimulation (COS). In fact, ovarian response did not differ between the two ovaries. Subgroup analyses according to the phase of the cycle at the initiation of COS, the type of malignancy, the use of letrozole and the magnitude of the ovarian response did not allow to identify any condition showing a difference in the follicular response between the active and the resting ovaries. In conclusion, follicular growth does not seem to be perturbed by the presence of a dominant follicle or a corpus luteum

Calcineurin controls expression of EAAT1/GLAST in mouse and human cultured astrocytes through dynamic regulation of protein synthesis and degradation

Alterations in the expression of glutamate/aspartate transporter (GLAST) have been associated with several neuropathological conditions including Alzheimer\u2019s disease and epilepsy. However, the mechanisms by which GLAST expression is altered are poorly understood. Here we used a combination of pharmacological and genetic approaches coupled with quantitative PCR and Western blot to investigate the mechanism of the regulation of GLAST expression by a Ca2+ /calmodulin-activated phosphatase calcineurin (CaN). We show that treatment of cultured hippocampal mouse and fetal human astrocytes with a CaN inhibitor FK506 resulted in a dynamic modulation of GLAST protein expression, being downregulated after 24\u201348 h, but upregulated after 7 days of continuous FK506 (200 nM) treatment. Protein synthesis, as assessed by puromycin incorporation in neo-synthesized polypeptides, was inhibited already after 1 h of FK506 treatment, while the use of a proteasome inhibitor MG132 (1 \ub5M) shows that GLAST protein degradation was only suppressed after 7 days of FK506 treatment. In astrocytes with constitutive genetic ablation of CaN both protein synthesis and degradation were significantly inhibited. Taken together, our data suggest that, in cultured astrocytes, CaN controls GLAST expression at a posttranscriptional level through regulation of GLAST protein synthesis and degradation

Assessing opportunities and weaknesses of green hydrogen transport via LOHC through a detailed techno-economic analysis

In the transition towards a more sustainable energy system, hydrogen is seen as the key low-emission energy source. However, the limited H2 volumetric density hinders its transportation. To overcome this issue, liquid organic hydrogen carriers (LOHCs), molecules that can be hydrogenated and, upon arrival, dehydrogenated for H2 release, have been proposed as hydrogen transport media. Considering toluene and dibenzyltoluene as representative carriers, this work offers a systematic methodology for the analysis and the comparison of LOHCs, in view of identifying cost-drivers of the overall value-chain. A detailed Aspen Plus process simulation is provided for hydrogenation and dehydrogenation sections. Simulation results are used as input data for the economic assessment. The process economics reveals that dehydrogenation is the most impactful cost-item, together with the carrier initial loading, the latter related to the LOHC transport distance. The choice of the most suitable molecule as H2 carrier, ultimately, is a trade-off between its hydrogenation enthalpy and cost.(c) 2023 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/)

Liquefied hydrogen value chain: A detailed techno-economic evaluation for its application in the industrial and mobility sectors

Green hydrogen can be efficiently produced in regions rich in renewable sources, far from the European large-production sites, and delivered to the continent for utilization in the industrial and mobility sectors. In this work, the transportation of hydrogen from North Africa to North Italy in its liquefied form is considered. A techno-economic assessment is performed on its value chain, which includes liquefaction, storage, maritime trans-port, distribution, regasification and compression. The calculated transport cost for the industrial application (delivery to a hydrogen valley) ranges from 6.14 to 9.16 euro/kg, while for the mobility application (delivery to refueling stations) the range is 10.96-17.71 euro/kg. In the latter case, the most cost-effective configuration involves the distribution of liquefied hydrogen and regasification at the refueling stations. The liquefaction process is the cost driver of the value chain in all the investigated cases, suggesting the importance of its optimization to minimize the overall transport cost