Linee guida per il progetto di Link Scheduling e Routing nelle Reti Wireless Mesh tramite Algoritmi Genetici

In questa tesi ci occuperemo delle reti Wireless Mesh (WMN – Wireless Mesh Network), che sono una delle tecnologie emergenti volte a fornire connettività a banda larga ai clienti mobili che si trovano nei pressi di reti wired; esse vengono impiegate anche in quelle zone dove non è possibile installare un’infrastruttura cablata. In particolare affronteremo il problema di massimizzare il minimo throughput che è possibile garantire ad ogni nodo della rete verso un specifico nodo, che funge da gateway. Invece di utilizzare un metodo tradizionale dove l’attivazione dei link viene scelta dopo che sono state svolte le funzioni di Routing, approcceremo il problema considerando il Link Scheduling e il Routing in modo congiunto. Dopo aver determinato una soluzione, che rappresenta l’attivazione dei link in un determinato periodo, si suppone una schedulazione periodica di essa. L’attivazione dei link viene condizionata dall’interferenza che i nodi producono con le loro trasmissioni; tale interferenza è modellata per mezzo del SIR (rapporto segnale-interferenza). Trovare un pattern di attivazione dei link che svolga contemporaneamente funzioni di routing e che garantisca un minimo throughput a tutti i router è un problema difficile da risolvere (NP-Complete), ed è pressochè impossibile, in topologie di reti con un numero elevato di nodi, trovare delle soluzioni in tempi ragionevoli utilizzando metodi esatti. Ricorreremo quindi ad una tecnica basata su algoritmi genetici, che ci permetterà di trovare in un tempo relativamente breve risultati soddisfacenti; dall’analisi dei risultati dell’applicazione di questi algoritmi sarà inoltre possibile ricavare delle linee guida per la progettazione di Link Scheduling e Routing nelle reti Wireless Mesh. Nei limiti delle nostre conoscenze, questa tipologia di algoritmi non è mai stata utilizzata per risolvere il problema di ottimizzazione suddetto nell’ambito delle reti wireless

Influence of battery aging on energy management strategy

In the context of Hybrid Electric Propulsion Systems, one of the main aspects to investigate is the most suitable energy management strategy, which would allow the objectives of fuel consumption minimization and electric backup availability to be attained. The present study aims to compare two different energy management strategies for a Hybrid Electric Propulsion System (HEPS) for a Air-Taxi vehicle: though both are based on the same set fuzzy rules, the first one has been implemented neglecting battery aging effects, while the second adjusts the optimal battery discharge according to its age. The impact of such adaptation on fuel consumption and battery State of Charge will be evaluated along a typical mission profile

Effect of different pastures on CLA content in milk and sheep cheese

It is known that milk composition included conjugated linoleic acid (CLA) is affected by animal feeding system (Cabiddu et al., 2001). In Sardinia dairy sheep feeding is mainly based on pastures. Most of them are characterised by self-regenerating species, like annual ryegrass (Lolium rigidum Gaudin) and burr medic (Medicago polymorpha L.). Non conventional species belonging to the Compositae family such as (Chrysanthemum coronarium L.) seem interesting for sheep feeding when other herbages decrease in quality (late spring- early summer). It was observed that C. coronarium establishes rapidly, can be grazed early in the growing season and persist where other pasture species may disappear; for these reasons it can be considered a valuable source of food. Moreover a preliminary study with dairy sheep fed fresh forage of C. coronarium showed relatively high levels of CLA in milk (Molle G. pers. com.) The aim of the present work was to study the influence of different pastures on milk composition, with particular reference to CLA and its precursors

Fine-tune control of targeted RNAi efficacy by plant artificial small RNAs

[EN] Eukaryotic RNA interference (RNAi) results in gene silencing upon the sequence-specific degradation of target transcripts by complementary small RNAs (sRNAs). In plants, RNAi-based tools have been optimized for high efficacy and high specificity, and are extensively used in gene function studies and for crop improvement. However, efficient methods for finely adjusting the degree of induced silencing are missing. Here, we present two different strategies based on artificial sRNAs for fine-tuning targeted RNAi efficacy in plants. First, the degree of silencing induced by synthetic-trans-acting small interfering RNAs (syn-tasiRNAs) can be adjusted by modifying the precursor position from which the syn-tasiRNA is expressed. The accumulation and efficacy of Arabidopsis TAS1c-based syn-tasiRNAs progressively decrease as the syn-tasiRNA is expressed from positions more distal to the trigger miR173 target site. And second, syn-tasiRNA activity can also be tweaked by modifying the degree of base-pairing between the 3' end of the syn-tasiRNA and the 5' end of the target RNA. Both strategies were used to finely modulate the degree of silencing of endogenous and exogenous target genes in Arabidopsis thaliana and Nicotiana benthamiana. New high-throughput syn-tasiRNA vectors were developed and functionally analyzed, and should facilitate the precise control of gene expression in multiple plant species.Ministerio de Ciencia, Innovacion y Universidades (MCIU); Agencia Estatal de Investigacion (AEI); Fondo Europeo de Desarrollo Regional (FEDER) [RTI2018-095118-A-100; RYC-2017-21648 to A.C.; BIO2017-83184-R to J.-A.D.]. Funding for open access charge: MCIU; AEI; FEDER [RTI2018-095118-A-100].López-Dolz, L.; Spada, M.; Daròs, J.; Carbonell, A. (2020). Fine-tune control of targeted RNAi efficacy by plant artificial small RNAs. Nucleic Acids Research. 48(11):6234-6250. https://doi.org/10.1093/nar/gkaa343S62346250481

Prefazione

La cooperazione internazionale nell’ambito dell’istruzione superiore è un settore strategico per la coesione sociale e lo sviluppo economico della nostra società. Diviene pertanto fondamentale supportare azioni che intendano proiettare elementi di valorizzazione dell’internazionalizzazione dell’offerta formativa nell’istruzione e offrire opportunità per stimolare la creatività e l’innovazione, per dare prospettive dinamiche all’integrazione economica e per attrarre i talenti. Si tratta di approcci di tipo filosofico in cui utilizzare metodi e paradigmi di rigore scientifico con apporti interdisciplinari e multidisciplinari che vadano a comprendere e interconnettere i sistemi complessi dell’agire

Constraining the Internal Structures of Venus and Mars from the Gravity Response to Atmospheric Loading

The gravity fields of celestial bodies that possess an atmosphere are periodically perturbed by the redistribution of fluid mass associated with the atmospheric dynamics. A component of this perturbation is due to the gravitational response of the body to the deformation of its surface induced by the atmospheric pressure loading. The magnitude of this effect depends on the relation between the loading and the response in terms of geopotential variations measured by the load Love numbers. In this work, we simulate and analyze the gravity field generated by the atmospheres of Venus and Mars by accounting for different models of their internal structure. By precisely characterizing the phenomena that drive the mass transportation in the atmosphere through general circulation models, we determine the effect of the interior structure on the response to the atmospheric loading. An accurate estimation of the time-varying gravity field, which measures the atmospheric contribution, may provide significant constraints on the interior structure through the measurement of the load Love numbers. A combined determination of tidal and load Love numbers would enhance our knowledge of the interior of planetary bodies, providing further geophysical constraints in the inversion of internal structure models.The gravity fields of celestial bodies that possess an atmosphere are periodically perturbed by the redistribution of fluid mass associated with the atmospheric dynamics. A component of this perturbation is due to the gravitational response of the body to the deformation of its surface induced by the atmospheric pressure loading. The magnitude of this effect depends on the relation between the loading and the response in terms of geopotential variations measured by the load Love numbers. In this work, we simulate and analyze the gravity field generated by the atmospheres of Venus and Mars by accounting for different models of their internal structure. By precisely characterizing the phenomena that drive the mass transportation in the atmosphere through general circulation models, we determine the effect of the interior structure on the response to the atmospheric loading. An accurate estimation of the time-varying gravity field, which measures the atmospheric contribution, may provide significant constraints on the interior structure through the measurement of the load Love numbers. A combined determination of tidal and load Love numbers would enhance our knowledge of the interior of planetary bodies, providing further geophysical constraints in the inversion of internal structure models

Evaluation of anatomical and histopathological changes in target organs of cattle slaughtered in Sardinia as a result of the illegal use of growth hormones. Preliminary results

Within the bovine specie, illegal use of anabolic agents can be grouped into four categories: beta-agonists, thyrostatics, glucocorticoids, sexual steroids. These substances, further their anabolic effect, cause morphological changes in target organs which can be evidenced by anatomical and histopathological testing. Such investigations are extremely important to screen and to detect in advance groups of animals in risk-breeding

Gender influence on professional satisfaction and gender issue perception among young oncologists. A survey of the Young Oncologists Working Group of the Italian Association of Medical Oncology (AIOM)

Background: The professional gender gap is increasingly recognised in oncology. We explored gender issues perception and gender influence on professional satisfaction/gratification among young Italian oncologists. Methods: Italian oncologists aged 6440 years and members of the Italian Association of Medical Oncology were invited to participate in an online survey addressing workload/burnout, satisfaction in professional abilities and relations, relevant factors for professional gratification, and gender barriers. \u3c72 test for general association or \u3c72 test for trend was used to analyse the data. Results: 201 young oncologists participated in the survey: 67% female, 71% aged 30-40 years, 41% still in training and 82% without children. Women and men were equally poorly satisfied by the relations with people occupying superior hierarchical positions. There was heterogeneity between women and men in current (p=0.011) and expected future (p=0.007) satisfaction in professional abilities: women were more satisfied by current empathy and relations with colleagues and were more confident in their future managerial and team leader skills. The most important elements for professional gratification indicated by all participants were, in general, work-life balance (36%) and intellectual stimulation/research (32%); specifically for women, work-life balance (48%) and intellectual stimulation/research (20%); and specifically for men, career (29%) and social prestige/recognition (26%). Heterogeneity within the same gender emerged. For example, the elements indicated by men as the most important were intellectual stimulation/research (39%) and work-life balance (21%) in general, versus social prestige/recognition (24%) and career (24%), respectively, specifically for men (p<0.0001). More women versus men perceived gender issue as an actual problem (60% vs 38%, p=0.03); men underestimated gender barriers to women's career (p=0.011). Conclusions: Satisfaction in professional abilities varied by gender. Work-life balance is important for both women and men. Stereotypes about gender issues may be present. Gender issue is an actual problem for young oncologists, mostly perceived by women