Development of piezoelectric harvesters with integrated trimming devices

Piezoelectric cantilever harvesters have a large power output at their natural frequency, but in some applications the frequency of ambient vibrations is different fromthe harvester\u2019s frequency and/or ambient vibrations are periodicwith some harmonic components. To copewith these operating conditions harvesters with integrated trimming devices (ITDs) are proposed. Some prototypes are developed with the aid of an analytical model and tested with an impulsive method. Results show that a small trimming device can lower the main resonance frequency of a piezoelectric harvester of the same extent as a larger tip mass and, moreover, it generates at high frequency a second resonance peak. A multi-physics numerical finite element (FE) model is developed for predicting the generated power and for performing a stress-strain analysis of harvesters with ITDs. The numerical model is validated on the basis of the experimental results. Several configurations of ITDs are conceived and studied. Numerical results show that the harvesters with ITDs are able to generate relevant power at two frequencies, owing to the particular shape of the modes of vibration. The stress in the harvesters with ITDs is smaller than the stress in the harvester with a tip mass trimmed to the same frequency

a pliosaurid plesiosaurian from the rosso ammonitico veronese formation of italy

Plesiosauria is a clade of medium to large bodied marine reptiles with a cosmopolitan distribution ranging from the latest Triassic to the end of the Cretaceous. In Europe, the fossil record of Plesiosauria is mainly known from the Northern latitudes, whereas it is much rarer from the Southern and Mediterranean areas. Here, we report the first articulated skeleton of an Italian plesiosaurian, from the Callovian-Oxfordian deposits of the Rosso Ammonitico Veronese Formation of Kaberlaba (Veneto). The specimen is referred to Pliosauridae based on the large size of the skull, compared to the appendicular skeleton, the presence of the lacrimal, and a distinct anterolateral projection of the prefrontal into the orbital margin. Mandibular and vertebral symplesiomorphies support the placement of the Italian taxon among the "gracile-longirostrine grade" of basal pliosaurids. The Kaberlaba plesiosaurian represents the second reptile clade recovered from the Rosso Ammonitico Veronese Formation, after Thalattosuchia

Acynodon adriaticus from Villaggio del Pescatore (Campanian of Italy): anatomical and chronostratigraphic integration improves phylogenetic resolution in Hylaeochampsidae (Eusuchia)

The hylaeochampsid crocodylomorph Acynodon adriaticus, from the uppermost Cretaceous ‘Villaggio del Pescatore’ site, belongs to an early diverging lineage in Eusuchia. Here an additional specimen, MCSNT 57031, is osteologically and osteohistologically described in detail. After integrating this morphological information together with the recent chronostratigraphic recalibration of the site to the loweremiddle Campanian, the tip-dated Bayesian phylogenetic analysis recovers this taxon in a monophyletic clade with the Spanish Acynodon iberoccitanus. Conflicting results from the maximum parsimony and Bayesian analyses, and discussion on the intraspecific variability between the specimens assigned to A. adriaticus, highlights the need for a detailed morphological description and integration with an updated phylogenetic scaffold, in order to resolve the monophyly of the genus Acynodon and the relationships of these branches of early diverging eusuchians. The curious discrepancy between morpho- and osteo-skeletal maturity suggest unique ecomorphological adaptations in this Campanian crocodylomorph.Agencia Estatal de Investigación | Ref. FJC2020-044836-IUniversidade de Vigo/CISU

Predictive Multi Experiment Approach for the Determination of Conjugated Phenolic Compounds in Vegetal Matrices by Means of LC-MS/MS

Polyphenols (PCs) are a numerous class of bioactive molecules and are known for their antioxidant activity. In this work, the potential of the quadrupole/linear ion trap hybrid mass spectrometer (LIT-QqQ) was exploited to develop a semi-untargeted method for the identification of polyphenols in different food matrices: green coffee, Crocus sativus L. (saffron) and Humulus lupulus L. (hop). Several conjugate forms of flavonoids and hydroxycinnamic acid were detected using neutral loss (NL) as a survey scan coupled with dependent scans with enhanced product ion (EPI) based on information-dependent acquisition (IDA) criteria. The presented approach is focused on a specific class of molecules and provides comprehensive information on the different conjugation models that are related to specific base molecules, thus allowing a quick and effective identification of all possible combinations, such as mono-, di-, or tri-glycosylation or another type of conjugation such as quinic acid esters

An Italian dinosaur Lagerstätte reveals the tempo and mode of hadrosauriform body size evolution

During the latest Cretaceous, the European Archipelago was characterized by highly fragmented landmasses hosting putative dwarfed, insular dinosaurs, claimed as fossil evidence of the “island rule”. The Villaggio del Pescatore quarry (north-eastern Italy) stands as the most informative locality within the palaeo-Mediterranean region and represents the first, multi-individual Konservat-Lagerstätte type dinosaur-bearing locality in Italy. The site is here critically re-evaluated as early Campanian in age, thus preceding the final fragmentation stages of the European Archipelago, including all other European localities preserving hypothesized dwarfed taxa. New skeletal remains allowed osteohistological analyses on the hadrosauroid Tethyshadros insularis indicating subadult features in the type specimen whereas a second, herein newly described, larger individual is likely somatically mature. A phylogenetic comparative framework places the body-size of T. insularis in range with other non-hadrosaurid Eurasian hadrosauroids, rejecting any significant evolutionary trend towards miniaturisation in this clade, confuting its ‘pygmy’ status, and providing unmatched data to infer environmentally-driven body-size trends in Mesozoic dinosaurs

Promoting the learning of modern and contemporary physics in high schools in informal and non-formal contexts

In this paper, we introduce active learning strategies developed by the Educational Division of the Physics Department of the University of Cagliari to promote the learning of modern and contemporary physics (e.g., general relativity, particle physics, cosmology, and related topics) in high schools in informal and non-formal contexts. We discuss their features and potential role in facilitating science and physics instruction by integrating pedagogical theory and education research. We illustrate our theoretical framework and the methodologies we implemented to design specific educational strategies - and the evaluation of their effectiveness - to improve motivation, curiosity, and interest in modern and contemporary physics, as well as bring these topics more extensively to high schools. Finally, examples of the proposed educational activities are presented and their implications in informal and non-formal contexts are discussed