1,721,174 research outputs found
Prevention in school communities Institutional programs and goodwill [La prevenzione nelle comunità scolastiche Programmi istituzionali e. buona volontà]
No full textCommunity weighted mean trait data of Italian forest understories
Full text linkPlant functional trait data aggregated at the community level (i.e., community weighted mean, CWM) are fundamental to study plant-environment relationships. Here, we provide a large database of CWM values of twelve traits reflecting several plant functions, including leaf, seed, whole-plant, clonal and bud bank traits. The CWMs were calculated in 201 forest stands (a statistically representative sample of all the Italian forests) across three biogeographic regions: Alpine, Continental, and Mediterranean. © 2019 The Author(s
On generic identifiability of 3-tensors of small rank
No full textWe introduce an inductive method for the study of the uniqueness of decompositions of tensors, by means of tensors of rank 1. The method is based on the geometric notion of weak defectivity. For three-dimensional tensors of type (a, b, c), a ≤ b ≤ c, our method proves that the decomposition is unique (i.e., k-identifiability holds) for general tensors of rank k, as soon as k ≤ (a + 1)(b + 1)/16. This improves considerably the known range for identifiability. The method applies also to tensor of higher dimension. For tensors of small size, we give a complete list of situations where identifiability does not hold. Among them, there are 4×4×4 tensors of rank 6, an interesting case because of its connection with the study of DNA strings
Lauree all'estero: Il vademecum dei riconoscimenti
No full textNel corso degli ultimi anni le statistiche mostrano un notevole incremento nel numero di studenti che scelgono di studiare all’estero. Le motivazioni che portano a tale scelta sono molteplici: dal beneficio di ricavarne un’esperienza culturale diversa mentre si acquisiscono nuove nozioni alla possibilità di evitare il test di ammissione a numero chiuso. Tuttavia, una delle difficoltà incontrate da chi ha seguito un percorso accademico internazionale consiste nella differente organizzazione dei vari sistemi universitari, che rende complessa l’equi- parazione fra i titoli rilasciati dagli atenei delle diverse nazioni con quelli italiani. In qualità di esperta del settore abbiamo intervistato la professoressa Ersilia Barbato, presidente del Corso di Laurea Magistrale in Odontoiatria e Protesi Dentaria presso l’Università degli Studi di Roma La Sapienza e direttore dell’Unità Operativa Complessa di Ortognatodonzia del Policlinico Umberto I
Come ridurre la diffusione dell’aerosol durante l’epidemia da COVID-19: una nota tecnica
No full textThe aim is to reduce the aerosol spread during dental treatments. The system is made of an already existing structure: a dirty towel basket. The structure has to be put directly above patient's head. A transparent cellophane has to cover the structure, to provide a laboratory hood-like structure. The efficacy of the "dental-hood" was tested with a semi-quantitative colorimetric assay. A room dedicated for a dental unit was covered by absorbent paper. An air-polishing system and a staining powder served for the purpose. Standardized photographs were acquired one hour after dental treatment with and without dental-hood. The treatment without the dental-hood produced staining until two meters from the dental chair, with a contamination of the floor and the furnishings sensibly higher compared with the dental-hood. According to the critical situation we are living, the dental-hood represents a simple, inexpensive and effective way to reduce aerosol spread during dental treatments
Functional and coenological changes under different long-term management conditions in Apennine meadows (central Italy)
No full textThe aim of this research was to study the floristic and ecological changes in sub-Mediterranean meadows due to three kinds of management entailing different disturbance intensities. The theoretic framework follows Grime’s theory about the correlation between species richness and disturbance intensities. Phytosociological relevés were carried out in three different management-disturbance situations, namely mowing and grazing, mowing alone, and abandonment. The data from these relevés were processed through statistical analysis, and examined together with ecological parameters (bioindication values and twenty functional plant traits) in order to indicate signifi cant differences within the diversely disturbed meadows. It was found that three identifi ed plant communities corresponded to three different disturbance intensities, and that species richness was comparable between high disturbance situation and those of void disturbance, whilst it considerably decreased under intermediate disturbance. High disturbance condition vs. void disturbance comparison showed the higher differences regarding: species turnover (57% of Sørensen similarity index and 45 differential species), light request and pH soil reaction. Hemicryptophytes, fringe social behaviour type (SBT3), upright forbs, clonal ability, late flowering period emerged as differential traits and species height increases moving to undisturbed situation. Other important evidences concern avoidance strategies which are favoured by mowing and grazing, whereas species equipped with late fl owering period and clonal ability are advantaged under intermediate and void disturbance conditions. Our fi ndings indicated that the species more threatened by abandonment are the accidental ones
Impact of alien species on dune systems: a multifaceted approach
No full textWe applied a multifaceted approach, in terms of taxonomic, phylogenetic and functional diversity, to study at fine scale how three plant communities occurring in a Mediterranean dune have been affected by the encroachment of alien species. We sampled 81 sites in a Site of Community Importance in Central Italy. Past and present land use/cover data have been derived using GIS and remote sensing tools. Information on plants phylogenesis and functional traits has been gathered from several databases. Ecological variables have been collected. GLMs in conjunction with an Information Based approach were used to model species composition, richness and phylogenetic diversity. Multivariate analysis has been used to study functional diversity. The results outlined how total species richness is related to recent land transformations and to a set of environmental factors. The analyses of functional and phylogenetic diversity support the idea that alien species significantly affect the functional and phylogenetic characteristics of the native plant communities. Habitat filtering seems to be predominant in not-invaded plots, whereas limiting similarity/niche differentiation is predominant in driving community assembly of invaded communities. The attained scenario depicts the spread of a reduced group of alien species phylogenetically and functionally well-differentiated, able to reduce the abundance of native species, not to exclude them though. Ultimately, the multifaceted approach assisted in understanding the community assembly of dune vegetation, and to discern the relative impact of alien species on native plant communities. Such approach represents a crucial step to achieve an efficient management of dune habitats, as useful tool to monitor and to effectively protect their biodiversity and functionin
Impact of alien species on dune systems: a multifaceted approach
No full textWe applied a multifaceted approach, in terms of taxonomic, phylogenetic and functional diversity, to study at fine scale how three plant communities occurring in a Mediterranean dune have been affected by the encroachment of alien species. We sampled 81 sites in a Site of Community Importance in Central Italy. Past and present land use/cover data have been derived using GIS and remote sensing tools. Information on plants phylogenesis and functional traits has been gathered from several databases. Ecological variables have been collected. GLMs in conjunction with an Information Based approach were used to model species composition, richness and phylogenetic diversity. Multivariate analysis has been used to study functional diversity. The results outlined how total species richness is related to recent land transformations and to a set of environmental factors. The analyses of functional and phylogenetic diversity support the idea that alien species significantly affect the functional and phylogenetic characteristics of the native plant communities. Habitat filtering seems to be predominant in not-invaded plots, whereas limiting similarity/niche differentiation is predominant in driving community assembly of invaded communities. The attained scenario depicts the spread of a reduced group of alien species phylogenetically and functionally well-differentiated, able to reduce the abundance of native species, not to exclude them though. Ultimately, the multifaceted approach assisted in understanding the community assembly of dune vegetation, and to discern the relative impact of alien species on native plant communities. Such approach represents a crucial step to achieve an efficient management of dune habitats, as useful tool to monitor and to effectively protect their biodiversity and functionin
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