Spontaneous emission of an atom near an oscillating mirror

We investigate the spontaneous emission of one atom placed near an oscillating reflecting plate. We consider the atom modeled as a two-level system, interacting with the quantum electromagnetic field in the vacuum state, in the presence of the oscillating mirror. We suppose that the plate oscillates adiabatically, so that the time-dependence of the interaction Hamiltonian is entirely enclosed in the time-dependent mode functions, satisfying the boundary conditions at the plate surface, at any given time. Using time-dependent perturbation theory, we evaluate the transition rate to the ground-state of the atom, and show that it depends on the time-dependent atom-plate distance. We also show that the presence of the oscillating mirror significantly affects the physical features of the spontaneous emission of the atom, in particular the spectrum of the emitted radiation. Specifically, we find the appearance of two symmetric lateral peaks in the spectrum, not present in the case of a static mirror, due to the modulated environment. The two lateral peaks are separated from the central peak by the modulation frequency, and we discuss the possibility to observe them with actual experimental techniques of dynamical mirrors and atomic trapping. Our results indicate that a dynamical (i.e., time-modulated) environment can give new possibilities to control and manipulate also other radiative processes of two or more atoms or molecules nearby, for example their cooperative decay or the resonant energy transfer

Trees and shrubs in the city of Bari (Italy)

The authors recorded in the city of Bari 221 specific and infraspecific taxa, used as onramentals, belonging to 126 genera of 64 families with a prevalence of exotic species over native ones. The study is preparatory to the redevelopment of urban green areas concerning the recent Municipal Regulation on green spaces in the city. The flora investigated is rich in elements native to Italy. Anyway, the most common species are commonly used as ornamental also in the other regions of Italy. Argania spinosa, Ceiba speciosa, Cyperus papyrus, Euphorbia ingens, Ficus rubiginosa, and Jacaranda mimosifolia are species less commonly used and noteworthy, because at their climatic limit

Magnesium Hydroxide Nanoparticles Production from Natural Bitterns

Magnesium hydroxide nanoparticles are widely employed in numerous industrial applications. Several preparation methods have been proposed using mainly synthetic Mg2+ containing solutions. In the present work, the possibility of producing Mg(OH)2 nanoparticles from real bitterns, the by-product of sea salt production, is investigated. Bitterns are highly concentrated Mg2+ containing solutions whose exploitation can turn a waste into valuable products embracing the circular economy idea. Two bitterns collected from Galia and Margi saltworks of the district of Trapani (Italy) were studied. Galia and Margi bitterns had a 1 M and 2.5 M Mg2+ concentration, respectively. A 2 mm diameter circular-cross sectional T-mixer was adopted to ensure fast reactant mixing. NaOH solutions were employed as precipitant agents. Mg(OH)2 nanoparticles characterized by cationic and mass purity higher than 99 % and 90 %, respectively, were successfully produced when treating Galia bitterns, while the excessive Margi Mg2+ concentration yielded stronger micrometer Mg(OH)2 agglomerates

Typification of names published by Vincenzo Tineo from Sicily

The nomenclature of 13 European taxa described by Vincenzo Tineo from Sicily is discussed. Alyssum nebrodense is neotypified on a specimen collected by Tineo and housed in PAL. Bromus tenuis (basionym of Vulpiella tenuis), Carex intricata (Carex nigra subsp. intricata), Ophrys sicula, Orchis markusii (Dactylorhiza markusii), Scilla sicula (Oncostema sicula), and Viola parvula are lectotypified using specimens deposited in PAL; Iris pseudopumila is lectotypified by a specimen preserved in K, Mespilus insegnae (Crataegus insegnae), Scilla ughii (Oncostema ughii), and Statice tenuicula (Limonium tenuiculum) are lectotypified by specimens housed in NAP; Rothia tenuifolia (Andryala tenuifolia) is neotypified by a specimen by Michele Lojacono-Pojero housed in P; Statice parviflora (Limonium parvifolium) is lectotypified on a specimen housed in FI. For each taxon both the currently accepted name and synonymies are provided. The type indication is followed by nomenclatural and taxonomic notes in which the original material found is commented and the reasons for the choice of the types are discussed

Forest nurseries and the National Recovery and Resilience Plan: the case of Sicily and Apulia (Italy)

In Italy, the National Recovery and Resilience Plan (NRRP) foresees the planting of ca. 6.6 million trees to establish urban and peri-urban forests in 14 metropolitan cities. This ambitious project requires a significant number of native trees and shrubs, currently unavailable in Italian public and private nurseries. This survey analyzes the state of forest nurseries in two administrative regions of southern Italy, i.e. the “Filici” forest nursery (province of Agrigento, Sicily) and the Gargano Mountain Reclamation Consortium (province of Foggia, Apulia), to evaluate the adequacy of Sicilian and Apulian forest nurseries as potential sources of plant material to meet the requirements of the NRRP. The census carried out at the “Filici” nursery revealed the presence of more than 22,000 seedlings in cultivation, comprising 55 species, 26 genera, and 26 families. The autochthonous species are 43 (78.2%), while the exotic ones are 12 (21.8%). The Gargano Mountain Reclamation Consortium forest nursery has 190,876 seedlings in cultivation. A total of 80 species are present, belonging to 59 genera and 32 families. Of these, 68 (85%) are native species, 12 (15%) are exotic. An analysis of the plant material being cultivated in these forest nurseries shows the presence of a share of autochthonous species of interest for urban reforestation initiatives, however these are still insufficient in number

A numerical analysis of non–linear contact tasks for the system of plates with a bolted connection and a clearance in the fixture

EN: Silos that are widely used in modern agriculture have several advantages, such as easy assembling, reliability, low cost, and easy management. Since there is a huge stress exerted upon silos, the stress-strain state (SSS) under the internal pressure of the grain bulk must be taken into account and thoroughly calculated. This entails the use of a particular calculation model for the metal structure elements of the considered silos. UK: Робота присвячується аналізу геометрично нелінійних контактних задач для системи смуг. Особливості представленої задачі полягають у дослідженні напружено-деформованого стану двох смуг, сполучених болтовим кріпленням із зазором і навантажених рівномірно роз- поділеним по верхній кромці поперечним зусиллям. У цій постановці задачі присутні геометрична і структурна нелінійності. Отримано основні закономірності напружено-деформованого стану елементів силосів. RU: Данная работа посвящается анализу геометрически нелинейных контактных задач для системы полос. Особенности представленной задачи заключаются в исследовании напряженно-деформированного состояния двух полос, соединенных болтовым крепежом с зазором и нагруженных равномерно распределенным по верхней кромке поперечным усилием. В данной постановке задачи присутствуют геометрическая и структурная нелинейности. Получены основные закономерности напряженно-деформированного состояния элементов силосов

Integrative Taxonomy of Armeria Taxa (Plumbaginaceae) Endemic to Sardinia and Corsica

Sardinia and Corsica are two Mediterranean islands where the genus Armeria is represented by 11 taxa, 10 out of which are endemic. An integrative approach, using molecular phylogeny, karyology, and seed and plant morphometry was used to resolve the complex taxonomy and systematics in this group. We found that several taxa are no longer supported by newly produced data. Accordingly, we describe a new taxonomic hypothesis that only considers five species: Armeria leucocephala and A. soleirolii, endemic to Corsica, and A. morisii, A. sardoa, and A. sulcitana, endemic to Sardinia

The Libyan collections in FI (Herbarium Centrale Italicum and Webb Herbarium) and studies on the Libyan Flora by R. Pampanini - Part 2

This work is the continuation of Part 1, published in 2015, and comprises the reconstruction of the original collections of new taxa described by R. Pampanini and other botanists and, where possible, typification of the new names and taxonomical updating. The material studied for the most part concerns Libyan specimens held in the FI and FI-W herbaria but in some case also K, LD, MPU, P, PAD, PAL, ULT. Other material, which Pampanini studied in Florence was subsequently conserved in other herbaria. Specimens belonging to 21 families have been examined, from the Najadaceae to Zygophyllaceae. As well as typification, bibliographical data have been provided for those already typified. In this second part, a total of 113 names have been indexed and 91 typified, taking the names validly published in the entire work to 353, of which 286 are typified. Also on this occasion, we have provided taxonomic updates for each taxon. The Conclusions present a synthetic sum of the taxa still recognised taxonomically (entirely, in new combinations, or with a new status) in recent works on the Flora of N. Africa, in general revisions of various systematic groups, or reconsidered by the authors of this present work. We have also investigated the phyto-geographic origins of the taxa [according to the dominions proposed by Quézel (1978) for N. Africa]. Finally we have very briefly indicated the presence of material of the R. Pampanini collections (for Cyrenaica, together with R. E. G. Pichi Sermolli in 1934) in the most important herbaria. The paragraph "Addenda et Corrigenda" has been added to the final part of the treatise and relates chiefly to taxa omitted from the first part, either on account of new information or as a result of errors which came to light after publication

The 12th “Iter Mediterraneum” in Tunisia, 24 March – 4 April 2014

The organization and logistics of the 12th OPTIMA Iter in Tunisia from 24 March to 4 April 2014 by OPTIMA and ATUTAX is here reported. The material used and the workflow are illustrated as reference for the organization of future similar collaborative botanical excursions

Integrative Taxonomy of Armeria arenaria (Plumbaginaceae), with a Special Focus on the Putative Subspecies Endemic to the Apennines

Three subspecies of Armeria arenaria are reported from Italy, two of which are considered endemic to the Apennines. The taxonomic value of these two taxa (A. arenaria subsp. marginata and A. arenaria subsp. apennina) is unclear. Moreover, the relationships between A. arenaria subsp. praecox and Northern Italian populations—currently ascribed to A. arenaria subsp. arenaria—have never been addressed. Accordingly, we used an integrated taxonomic approach, including morphometry, seed morpho–colorimetry, karyology, molecular systematics (psbA–trnH, trnQ–rps16, trnF–trnL, trnL–rpl32, and ITS region), and comparative niche analysis. According to our results, French–Northern Italian populations are clearly distinct from Apennine populations. In the first group, there is evidence which allows the recognition of A. arenaria s.str. (not occurring in Italy) and A. arenaria subsp. praecox. In the second group, the two putative taxa endemic to the Northern Apennines cannot be separated, so a single subspecies is here recognized: A. arenaria subsp. marginata