33 research outputs found
Graphene oxide impairs the pollen performance of Nicotiana tabacum and Corylus avellana suggesting potential negative effects on the sexual reproduction of seed plants
The production of graphene based materials (GBMs) is steadily increasing but the effects of the possible release of GBMs in the environment are far from being understood. Graphene oxide (GO) is among the most active GBMs and it causes widely varying effects on the vegetative body of seed plants. However, nothing is known yet about its potential effects on the reproductive process. This study addresses the effects of GO on pollen germination and pollen tube elongation in the model species Nicotiana tabacum and in the non-model species Corylus avellana. In vitro germination experiments were conducted without or with GO (control and treated samples, respectively) at concentrations of 25, 50 and 100 μg mL−1. Pollen germination and tube elongation were affected at GO concentrations ≥50 μg mL−1, decreasing by 20% and 19% in N. tabacum and by 68% and 58% in C. avellana, respectively. GO did not affect the viability of N. tabacum pollen, but doubled the frequency of bent tubes. Microscopy observations of pollen tubes exposed to a cellpermeant, dual-excitation ratiometric pH indicator revealed that GO affected the intracellular pH homeostasis. Further germination experiments on C. avellana conducted by inverting the pH conditions of the control and treated (100 μg GO mL−1) samples demonstrated that the main factor influencing the pollen performance is the acidic properties of GO. This might affect the reproductive process of numerous seed plants thus being relevant from an environmental point of view
Notulae to the Italian alien vascular flora: 2
In this contribution, new data concerning the Italian distribution of alien vascular flora are presented. It includes new records, exclusions and confirmations for Italy or for Italian administrative regions for taxa in the genera Ageratum, Aster, Buddleja, Cedrus, Centranthus, Cephalotaxus, Clerodendrum, Cotoneaster, Cyperus, Honorius, Lantana, Ligustrum, Morus, Muscari, Oenothera, Opuntia, Platycladus, Plumbago, Pseudotsuga, Sedum, Sporobolus, Stachys, Ulmus and Yucca. A nomen novum, Stachys talbotii, is proposed as a replacement name for Sideritis purpurea
Notulae to the Italian native vascular flora: 10
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions for taxa in the genera Artemisia, Chaetonychia, Cirsium, Cynanchum, Genista, Hieracium, Iberis, Melica, Misopates, Myosotis, Thalictrum, Trifolium, Utricularia, Veronica, and Vicia. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as supplementary material
Notulae to the Italian native vascular flora: 5.
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records and confirmations to the Italian administrative regions for taxa in the genera Allium, Arabis, Campanula, Centaurea, Chaerophyllum, Crocus, Dactylis, Dianthus, Festuca, Galanthus, Helianthemum, Lysimachia, Milium, Pteris, and Quercus. Nomenclature and distribution updates, published elsewhere, and corrections are provided as supplementary material
Notulae to the Italian native vascular flora: 4
In this contribution new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, exclusion, extinction and confirmations to the Italian administrative regions for taxa in the genera Androsace, Artemisia, Fragaria, Melampyrum, Myosotis, Petrorhagia, Phillyrea, Rosa, Rumex, Spiranthes, Trifolium, and Vicia. Furthermore, a new combination in the genus Omalotheca is proposed
Progettazione e Sviluppo di un'applicazione client-server per la simulazione di servizi NFC forniti da un operatore di rete mobile
Si vogliono eseguire azioni informative ed educative per aumentare la confidenza dei consumatori nell’uso della tecnologia NFC.
In particolare si prevede la disposizione, all’interno di alcuni retail di operatori telefonici, di appositi totem digitali, dotati di tecnologia NFC, che rendono disponibili agli utenti dei servizi interattivi. Tali totem, che avranno a disposizione anche uno smartphone di prova dotato di NFC, permetteranno agli utenti di provare diverse modalità d’uso in differenti contesti. Essi utilizzeranno delle animazioni per guidare l’utente nella user experience degli scenari di utilizzo progettati.
Parte integrante del progetto è l'identificazione di alcuni strumenti in grado di permettere agli utenti di rilasciare feedback sull’esperienza provata.
Lo scopo del progetto è stato, pertanto, quello di ideare e definire uno o più demo da rendere disponibili sui totem digitali, partendo da un’analisi dei modelli simili già esistenti in altri paesi, passando a ideare e definire gli scenari e le modalità di utilizzo da simulare e concludendo con la progettazione e la realizzazione del contenuto multimediale e delle interazioni necessarie per eseguire le diverse demo