6,950 research outputs found
CUBESATS: PAVING THE WAY TOWARDS AN EFFECTIVE RELIABILITY – ORIENTED APPROACH
No full textCubeSats enable the development of a new Space economy towards a Space that is now open and accessible to all kinds of activities,
industries and even end-users. However, the failure rate of these satellites is high enough to significantly contribute to the Low-Earth
Orbit congestion. This issue can be addressed with a gradual decrease of the formation rate of new debris, while removing the
existing one, to prevent future collisions. To ensure a long-term sustainability in Space, a Design for Reliability approach on the new
generation of CubeSats could enable a safe and effective maintenance in LEO. Reliability procedures applied from the beginning of
the design process can significantly improve the mission success rates
"Francisco Pizarro" de Rosa Arciniega: Un intento de legitimacion de la voz de una historiadora
No full textA reading of the historical novel Francisco Pizarro, written by the Peruvian Rosa Arciniega in 1936, is proposed. Through the analysis of the work, we will reflect on the relationship of the writer with the national historiography and with the ideal of a woman who dominated Latin American political and cultural discourse in the first half of the 20th century. From this, we seek to identify the place that the author constructs for herself within the intellectual field
Sistema di visione coassiale per l'inseguimento di giunti e il monitoraggio di processi di saldatura laser
No full textDipolar host/guest interactions and geometrical confinement at the basis of the stability of one dimensional ice in zeolite bikitaite
No full textThe integration of population genomics and association mapping using a landrace meta-population and historical data on commercial varieties elucidates the genetic basis of adaptation to Mediterranean conditions in barley (Hordeum vulgare L.)
No full textIdentifying the genomic regions responsible for the adaptation to different agroecological conditions and subtending environmentally adaptive phenotypic traits is a fundamental task for biologists, geneticists, and breeders.
This Ph.D. thesis reports the results of different but complementary experiments carried out to understand plant adaptation processes. The evolutionary history of a barley landrace metapopulation collected in Sardinia, Italy, and evolved under Mediterranean conditions was exploited together with historical data recorded on commercial varieties grown in the same environments.
Two main objectives were pursued. The first was to investigate the level and structure of the genetic diversity of barley landrace populations and to determine how this diversity was shaped. To accomplish this task, the role of the different evolutionary forces (genetic drift, migration, and selection) in shaping the current germplasm diversity has been studied. The second objective was to decipher the genetic basis of barley adaptation to diverse environmental and agro-ecological conditions (for bioclimates, latitude, and crop use). Several population genomic analyzes and signatures of selection mapping methods were integrated. Phenotypic characterisations of diverse plant materials and comparative genome-wide association studies were performed. Genomic maps of regions putatively under divergent selection and associated with environmentally adaptive traits such as heading date, plant height, leaf width, erect/prostrate growth habit, thousand-kernel weight, kernels per m2, and grain yield have been produced. The role of candidate genes comprised in these regions has been discussed.
The genomic regions identified will support the breeding of new varieties better adapted to current environmental conditions and future climate changes and the implementation of appropriate strategies for the conservation of agrobiodiversity
Supramolecular organization of water–ethanol solution in ferrierite under pressure
No full textTurning disorder into organization is a key issue in science. In particular, supramolecular organization induced by external stimuli has opened new paths for the bottom-up fabrication of nanostructures. By using a combined strategy based on the synergy of X-ray powder diffraction experiments and modeling studies [1], we showed that high pressure - in combination with the shape and space constraints of a hydrophobic all-silica zeolite - separate an ethanol–water liquid mixture into ethanol dimer wires and water tetramer squares (Figure 1). Separation of ethanol from water was accomplished in an all-silica ferrierite (Si-FER), by using as pressure transmitting medium a mixture of (1:3) ethanol and water in the 0.20 to 1.34 GPa pressure range. The system was studied in situ by high-pressure synchrotron X-ray powder diffraction at BM01 beamline at ESRF and refined via first principles modeling. Upon separation, the confined supramolecular blocks alternate in a binary two-dimensional architecture that remains stable upon complete pressure release. This unique architecture might rationalize the high selectivity of Si-FER in the separation of alcohol–water mixtures, a key issue in biofuel production. Moreover, as ferrierite is an exceptionally selective catalyst for biofuel synthesis in its hydrophilic Brønsted acid form, while only its pore entrances are actually exploited, we suggest that pressure could also be beneficial for the catalytic performance by enforcing the intrusion of reactants. These results support the combined use of high pressures and porous networks as a viable strategy for driving the organization of molecules or nano-objects towards complex, pre-defined patterns relevant for the realization of novel functional nanocomposites. [1] Arletti, R., Fois, E., Gigli, L., Vezzalini, G., Quartieri, S., Tabacchi, G. (2017) Angewandte Chemie, DOI: 10.1002/anie.20170021
Anatol Stern e Bruno Jasieński
No full textThe Author presents her first Italian translation of Anatol Stern's article (excerpted from his monograph on Polish Avant-garde "Rebelled Poetry. Sketches on Interwar Period Poetry" [1964, 2nd issue 1970]) about an other prominent initiator and ideologist of Polish Futurism, Bruno Jasieński. After the "Thaw", Stern first contributed to Jasieński's rehabilitation, publishing his poetry and the novel "I burn Paris" and writing several essays about his work. The presented article also offers a large choice of translated fragments of Jasieński's poetry, just a few known in Italy, and a Stern's artistic profile with a bibliography of his Italian version work
L'isola che non c'è. Il ruolo della cartografia nelle controversie attorno agli usi e al possesso degli isolotti alluvionali e delle aree golenali del Ticino al tramonto dell'età moderna
No full textNel corso dell’età moderna, e non solo, la gestione e il possesso delle risorse naturali hanno dato origine a molte controversie, legate al sedimentarsi di diritti e giurisdizioni, all’evoluzione del contesto socioeconomico locale o regionale, ai mutamenti di ordine istituzionale e così via. Questi conflitti tendevano a essere particolarmente frequenti quando la disponibilità di queste risorse stava cambiando, sia a causa dell’azione umana sia a causa di specifiche condizioni ambientali. L’articolo si focalizza su una risorsa particolarmente soggetta a cambiamenti, vale a dire gli isolotti alluvionali fluviali e le aree golenali che, per effetto della naturale evoluzione del corso dei fiumi, si rendevano o meno disponibili all’occupazione antropica, alla rivendicazione giurisdizionale e allo sfruttamento economico. L’area indagata si concentra sul caso del fiume Ticino e sul tratto interessato dai possedimenti dell’Ospedale Maggiore di Milano, una prestigiosa istituzione assistenziale e uno dei maggiori proprietari terrieri della fertile bassa pianura lombarda, dove il controllo delle acque fluviali era molto importante per alimentare la fitta rete irrigua. Tra le fonti primarie sulle dispute per l’uso delle isole e delle aree golenali del Ticino, disponibili nell’archivio dell’Ospedale Maggiore di Milano, abbiamo condotto un’analisi integrata tra fonti scritte, disegni e cartografia, al fine di comprendere meglio l’intricata trama e l’uso sapiente di diversi documenti per attestare i diritti in una disputa
Pressure-induced penetration of water-ethanol mixtures in all-silica ferrierite
No full textThe all-silica synthetic zeolite Si-FER has been compressed using ethanol/water mixture as pressure transmitting medium (PTM). Analysis of the diffraction data indicates that both components of the PTM penetrate into the zeolite cavities. First-principles molecular dynamics simulations were performed to explore the roomtemperature behavior of the Si-FER/ethanol/water system. The results suggest that the organic molecules tend to form hydrogen bonded dimers, which may also be hydrogen bonded to water molecules
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