Path-integral over non-linearly realized groups and Hierarchy solutions

The technical problem of deriving the full Green functions of the elementary pion fields of the nonlinear sigma model in terms of ancestor amplitudes involving only the flat connection and the nonlinear sigma model constraint is a very complex task. In this paper we solve this problem by integrating, order by order in the perturbative loop expansion, the local functional equation derived from the invariance of the SU(2) Haar measure under local left multiplication. This yields the perturbative definition of the path-integral over the non-linearly realized SU(2) group.Comment: 26 page

Spectroscopic and Structural Properties of β-Tricalcium Phosphates Ca9RE(PO4)7 (RE = Nd, Gd, Dy)

Rare-earth-based Ca9RE(PO4)7 (RE = Nd, Gd, Dy) materials were synthesized by solid-state reaction at T = 1200 °C. The obtained tricalcium phosphate (TCP) materials are efficient light emitters due to the presence of RE3+ ions, although these ions are present at high concentrations. Moreover, in these host structures, these ions can be used as optical probes to study their local environments. Thus, photoluminescence (PL) emission spectra of the powder samples clearly indicated, for Dy3+ and Gd3+ ions, the presence of the RE3+ ion in low-symmetry sites with some local structural disorder, and the spectra show the presence of vibrational features (in the case of Gd3+). For the Nd3+ phase, emission bands are present around 900, 1050, and 1330 nm, originating from the 4F3/2 level. In general, these RE-TCP samples are interesting luminescent materials in the visible (Dy), UV (Gd), and NIR (Nd) regions, due to weak concentration quenching even for high concentrations of the emitting ion

Morphology and luminescence of nanocrystalline Nb₂O₅ doped with Eu³⁺

The synthesis of nanocrystalline Nb2O5:Eu3+ has been achieved by using a Pechini procedure. The obtained materials are single-phase niobia with the orthorhombic structure, average crystallite size around 25nm and average lattice strain of about 0.002. TEM images show that the particles are rectangular and reasonably isolated. The luminescence of the Eu3+ ions in the niobia lattice is efficient and affected by a strong inhomogeneous broadening, due to an important disorder around the lanthanide ions

Lighthouse: A spacebased mission concept for the surveillance of geosynchronous space debris from low earth orbit

In this paper, a new mission is proposed for space debris surveillance in geosynchronous orbit (GEO). The mission "Lighthouse", here proposed as a concept study, describes the use of a small satellite in a low polar orbit, equipped with a Schmidt telescope, constantly observing a belt across the geostationary orbit. In this way, a single instrument can sweep the whole orbit everyday regardless the light and weather conditions. Most of observations are nowadays performed by ground telescopes, which are affected by weather conditions and night time duration. Moreover, a single telescope can observe only a portion of the geostationary orbit. The mission concept arose as space application of an ESA ITI (Innovation Triangle Initiative) project designing a Schmidt telescope purposely conceived for the monitoring of NEO (Near Earth Objects) and space debris. A compact version of the telescope (50 cm diameter and 1.61 m length), particularly suitable for space applications, has been designed too. The size and the mass of the telescope enable the use of a small satellite platform, with the related advantages in term of costs and performance. Lighthouse is proposed as a new asset for Space Surveillance and Tracking sensors, complementary to the ground telescopes network

Digitalization and valorization of the genotypic and phenotypic information retained within the FEM grapevine germplasm

The maintenance and valorization of genetic diversity is an undoubtable resource for the viticulture of the future, since the climate crisis is forcing us to think of new, more resilient varieties. For this reason, the grapevine germplasm of the Fondazione Edmund Mach has been continuously expanded in the last decade to a total of 3,120 accessions, whose trueness-to-type has been verified by means of the universal set of nine microsatellites. About two thirds are V. vinifera subsp. vinifera accessions, while the rest consists of naturalized and selected hybrids, V. vinifera subsp. sylvestris, and pure species. The genetic material has also been characterized over three consecutive years for ampelographic, vine development, and biotic stress response traits to be exploited for experimental purposes. All the data and metadata have been digitalized and hosted in a SQL database, the FEMVitisDB, developed with an ontology driven paradigm to annotate the deposited information. The database was built following the MIAPPE checklist to ensure data FAIRness. A RESTful WebServiceAPI based on BrAPI and a web frontend were developed to easily explore the information in the repository. Findings about the captured genetic diversity, the identified unique profiles, and the scouted unknown and therefore novel genotypes will be discussed. The latter enrich the genetic asset of the grapevine community, towards the feeding of international databases. Where feasible, the first degree of parentage relationship has been reconstructed. Finally, the outcomes regarding the inferred phenological core collections will be introduced to provide an information arsenal for future ’omics analyses

Emergent Ascomycetes in viticulture: an interdisciplinary overview

The reduction of pesticide usage is a current imperative and the implementation of sustainable viticulture is an urgent necessity. A potential solution, which is being increasingly adopted, is offered by the use of grapevine cultivars resistant to its main pathogenic threats. This, however, has contributed to changes in defense strategies resulting in the occurrence of secondary diseases, which were previously controlled. Concomitantly, the ongoing climate crisis is contributing to destabilizing the increasingly dynamic viticultural context. In this review, we explore the available knowledge on three Ascomycetes which are considered emergent and causal agents of powdery mildew, black rot and anthracnose. We also aim to provide a survey on methods for phenotyping disease symptoms in fields, greenhouse and lab conditions, and for disease control underlying the insurgence of pathogen resistance to fungicide. Thus, we discuss fungal genetic variability, highlighting the usage and development of molecular markers and barcoding, coupled with genome sequencing. Moreover, we extensively report on the current knowledge available on grapevine-ascomycete interactions, as well as the mechanisms developed by the host to counteract the attack. Indeed, to better understand these resistance mechanisms, it is relevant to identify pathogen effectors which are involved in the infection process and how grapevine resistance genes function and impact the downstream cascade. Dealing with such a wealth of information on both pathogens and the host, the horizon is now represented by multidisciplinary approaches, combining traditional and innovative methods of cultivation. This will support the translation from theory to practice, in an attempt to understand biology very deeply and manage the spread of these Ascomycetes