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Observation of Λ Hyperon Local Polarization in p-Pb Collisions at sqrt{s_NN}=8.16 TeV
No full textThe polarization of the Λ and Λ ̄ hyperons along the beam direction has been measured in proton-lead (p-Pb) collisions at a center-of-mass energy per nucleon pair of 8.16 TeV. The data were obtained with the CMS detector at the LHC and correspond to an integrated luminosity of 186.0±6.5 nb-1. A significant azimuthal dependence of the hyperon polarization, characterized by the second-order Fourier sine coefficient Pz,s2, is observed. The Pz,s2 values decrease as a function of charged particle multiplicity, but increase with transverse momentum. A hydrodynamic model that describes the observed Pz,s2 values in nucleus-nucleus collisions by introducing vorticity effects does not reproduce either the sign or the magnitude of the p-Pb results. These observations pose a challenge to the current theoretical implementation of spin polarization in heavy ion collisions and offer new insights into the origin of spin polarization in hadronic collisions at LHC energies
Unveiling the occurrence and role of Methylobacterium endophytes in olive trees: insights into potential interactions with Xylella fastidiosa subsp. pauca
No full textBackground: Olive quick decline syndrome (OQDS), caused by Xylella fastidiosa subsp. pauca (Xfp), is a destructive vascular disease affecting olive trees, particularly in Apulia, Southeastern Italy. Control measures rely on containment and replanting with resistant cultivars. Endophytic bacteria, including Methylobacterium spp., have shown potential in mitigating vascular diseases. These facultative methylotrophic bacteria inhabit xylem vessels and compete with pathogens like Xfp by producing siderophores that limit iron availability. Results: Analysis of endophytic bacterial populations in olive trees identified Methylobacterium spp. in both healthy and Xfp-infected plants, with variable isolation frequencies. Molecular identification based on 16S rDNA and mxaF gene sequences classified isolates as M. radiotolerans (70%) and M. mesophilicum (30%). Phylogenetic analysis showed limited genetic variation, clustering isolates with reference strains. In vitro experiments revealed that culture supernatants from Methylobacterium spp., grown in siderophore-inducing media, affected Xfp growth in a concentration-dependent manner. At low concentrations (up to 2%), supernatants stimulated Xfp growth, while higher concentrations (20% and 50%) inhibited growth. Selected strains of M. radiotolerans and M. mesophilicum were confirmed as siderophore producers through CAS blue agar tests and targeted LC–MS/MS analysis. LC–MS/MS identified ferrioxamine E and ferrichrome in all Methylobacterium strains, with the highest levels in M. organophilum and M. aminovorans. Deferoxamine was absent, whereas Xfp exhibited elevated production of ferrioxamine E, deferoxamine, and ferrichrome. Conclusions: This study underscores the biocontrol potential of Methylobacterium spp. against Xfp, suggesting an ability to compete with the pathogen through siderophore-mediated mechanisms. The dual effect of Methylobacterium supernatants—stimulatory at low concentrations and inhibitory at higher levels—highlights the complexity of plant–microbe–pathogen interactions. The production of ferrioxamine E and ferrichrome suggests a possible role in modulating iron availability in vivo, potentially reducing Xfp's growth and virulence. These findings provide a basis for developing Methylobacterium spp. as sustainable biocontrol agents to manage Xfp in olive production systems
Trends, Challenges, and Viability in Green Hydrogen Initiatives
No full textThis review explores the current status of green hydrogen integration into energy and industrial ecosystems. By considering notable examples of existing and developing green hydrogen initiatives, combined with insights from the relevant scientific literature, this paper illustrates the practical implementation of those systems according to their main end use: power and heat generation, mobility, industry, or their combination. Main patterns are highlighted in terms of sectoral applications, geographical distribution, development scales, storage solutions, electrolyzer technology, grid interaction, and financial viability. Open challenges are also addressed, including the high production costs, an underdeveloped transport and distribution infrastructure, the geopolitical aspects and the weak business models, with the industrial sector appearing as the most favorable environment where such challenges may first be overcome in the medium term
Take Me Home, Country Roads: Historical Diasporas and Contemporary FDI Patterns
No full textWe examine whether historical diasporas shape current foreign direct investment (FDI) flows, using Italian data from the ‘age of mass migration’ (1876–1925). We find that Italian regions with larger diasporas at the turn of the twentieth century maintain persistent economic ties with their historical destinations. Specifically, our gravity estimates show that greater historical diasporas are associated with larger inward and outward FDI flows between 2003 and 2015, with effect sizes that largely outweigh those of current migration. The stronger effects for taste-sensitive functions and the complementarity with current migration point to culture and taste convergence as key mechanisms
Enhancing Stallion Semen Cryopreservation: Selected Antioxidant Extracts and Sperm Freezability
No full textCryopreservation of equine semen remains challenging due to pronounced individual variability in cryotolerance. Because freezing induces oxidative stress and spermatozoa are particularly susceptible to such damage, this study aimed to comparatively evaluate the effects of natural extracts from nutraceutical compounds with high antioxidant activity, specifically matcha, spirulina, and horseradish, as well as quercetin, a well-known antioxidant molecule. These compounds were added to the freezing extender, and semen from 12 Salernitano stallions (48 ejaculates in total) was analyzed. Several parameters were assessed, including sperm kinetics, bioenergetics, oxidative and nitrosative stress markers, and the sperm DNA fragmentation index, both before and after cryopreservation. Neither the natural extracts nor quercetin significantly improved sperm freezability, likely due to the high degree of inter-individual variability. Stallion age also had a significant effect on nearly all the parameters evaluated, although no significant interactions were observed between age and treatment for any of the sperm quality traits. In conclusion, supplementation of the freezing extender with matcha, spirulina, horseradish extracts, or quercetin did not significantly enhance stallion semen cryopreservation outcomes. Conversely, stallion age and individual variability had a marked effect on sperm cryotolerance, highlighting the need for customized and holistic strategies to optimize cryotolerance in individual stallions
La cuestión de la autoría entre la tradición oral y la escritura
No full textFolklore studies have focused primarily on analyzing works of popular literature, leaving the authorship of these works and the processes that give rise to local and national traditions in the background. Yet, individual contributions to popular literature ought to be fully acknowledged so as to highlight how they are incorporated into a collective cultural system through processes of sharing, reproduction, codification, and transmission that respond to normative – and therefore social – needs. In this essay, the author supports this thesis based on two case studies. The first concerns the origin and spread of a traditional religious song that circulated in southern Italy in the 1930s in both oral and written form. The second concerns Rocco Scotellaro’s claim of co-authorship of the Canzone della Rabata, which was at the center of a heated controversy between him and Ernesto de Martino in the early 1950s, while it also sheds light on Scotellaro’s role in the developments of Tricarico’s Carnival parade.Los estudios sobre el folclore se han centrado principalmente en el análisis de las obras de la literatura popular, dejando en un segundo plano la autoría de las mismas y los procesos que dan origen a las tradiciones locales y nacionales. Sin embargo, las contribuciones individuales sobre la literatura popular deberían reconocerse plenamente, con el fin de poner de relieve cómo se incorporan a un sistema cultural colectivo a través de procesos de intercambio, reproducción, codificación y transmisión que responden a necesidades normativas y, por lo tanto, sociales. En este ensayo, se defiende esta tesis basándonos en dos casos de estudio. El primero, se refiere al origen y la difusión de un canto religioso tradicional que circulaba en el sur de Italia en los años treinta, tanto en forma oral como escrita. El segundo se refiere a la reivindicación de Rocco Scotellaro de la coautoría de la Canzone della Rabata, que fue objeto de una acalorada controversia entre él y Ernesto de Martino a principios de los años cincuenta del siglo pasado, al tiempo que arroja luz sobre el papel de Scotellaro en la evolución del desfile de Carnaval de Tricarico