233 research outputs found
Constitutively Activated PI3K Accelerates Tumor Initiation and Modifies Histopathology of Breast Cancer
The gene encoding phosphatidylinositol 3-kinase catalytic subunit α-isoform (PIK3CA, p110α) is frequently activated by mutation in human cancers. Based on detection in some breast cancer precursors, PIK3CA mutations have been proposed to have a role in tumor initiation. To investigate this hypothesis, we generated a novel mouse model with a Cre-recombinase regulated allele of p110α (myristoylated-p110α, myr-p110α) along with p53fl/fl deletion and KrasG12D also regulated by Cre-recombinase. After instillation of adenovirus-expressing Cre-recombinase into mammary ducts, we found that myr-p110α accelerated breast tumor initiation in a copy number-dependent manner. Breast tumors induced by p53fl/fl;KrasG12D with no or one copy of myr-p110α had predominantly sarcomatoid features, whereas two copies of myr-p110α resulted in tumors with a carcinoma phenotype. This novel model provides experimental support for importance of active p110α in breast tumor initiation, and shows that the amount of PI3K activity can affect the rate of tumor initiation and modify the histological phenotype of breast cancer
Plant communities of Italy. The vegetation prodrome
The Vegetation Prodrome of Italy was promoted in 2012 by the Italian "Ministry of Environment, Land and Sea Protection", in collaboration with the "Italian Society of Botany", to provide a comprehensive and systematic catalogue and description of Italian plant communities. The Prodrome that is presented in this paper is the first full organic synthesis of the vegetation of Italy at the alliance syntaxonomic level. It fulfils several needs, the main one being a unified and comprehensive national framework that may make an important contribution to the definition of the European Vegetation Prodrome. Syntaxonomy, as well as taxonomy, is sometimes based on considerations that may in part diverge: several authors tend to favour models that are divisive or aggregative to a greater or lesser extent in terms of flora, biogeography and ecology. These different points of view stimulate the scientific debate and allow the adoption of a framework that is more widely supported. The Prodrome includes 75 classes, 2 subclasses, 175 orders, 6 suborders and 393 alliances. The classes were grouped into nine broad categories according to structural, physiognomic and synecological elements rather than to syntaxonomic criteria. The rank, full valid name, any synonymies and incorrect names are provided for each syntaxon. The short declaration highlights the physiognomy, synecology, syndynamics and distribution of the plant communities that belong to the syntaxon. The Prodrome of the Italian Vegetation is linked to the European Strategy for Biodiversity, the European Habitats Directive and the European Working Groups related to the ecosystems and their services. In addition to basic applications, the Prodrome can be used as a framework for scientific research related to the investigation of the relationships between plant communities and the environmental factors that influence their composition and distribution
Silicon quantum dots in photovoltaic devices: device fabrication, characterization and comparison of materials
The realization of crystalline silicon tandem solar cells relies on silicon nanocrystal (Si NC) quantum dots as
the absorber of the top solar cell. Quantum confinement of charge carriers within the nanocrystals permits to
achieve a band gap up to 2 eV which can be adjusted according to the size of the nanocrystals. This enables the
construction of all-crystalline Si tandem solar cells, and increases the theoretical efficiency limit from 33 % to
42.5 % due to the addition of a second band gap. In this work, the electrical and photovoltaic properties of Si
NC films are assessed and the most prominent material systems (SiO2, Si3N4, SiC) are compared. P-i-n solar
cells are presented which feature Si NC as the intrinsic absorber layer and permit to characterize quantum
confinement electrically on device level. P-i-n solar cells with Si NC in SiC in the i-region have yielded open
circuit voltages of up to 370mV
New national and regional Annex I Habitat records: from #60 to #82
New Italian data on the distribution of the Annex I Habitats are reported in this contribution. Specifically, 8 new occurrences in Natura 2000 sites are presented and 49 new cells are added in the EEA 10 km Ă 10 km reference grid. The new data refer to the Italian administrative regions of Campania, Calabria, Marche, Piedmont, Sardinia, Sicily, Tuscany and Umbria. ReleveÌs and figures are provided as Supplementary material respectively 1 and 2. Copyright Antonio Morabito et al
First overview on the 4th Annex I Habitats Report in Italy: methods, criticality, results and future prospects
Like all the other EU/28 countries, in 2019 Italy developed the 4th Italian Report
ex-Art. 17 on the conservation status of the Habitats of Annex I to the 92/43/EEC
Directive. Institutional referent of the process, on behalf of the Ministry for
Environment, Land and Sea Protection (MATTM), was the Italian Institute for
Environmental Protection and Research (ISPRA) with the scientific support of the
Italian Botanical Society (SBI). A huge working group composed of thematic and
territorial experts was formed with the task to collect, analyse, validate the data
resulting from Annex I Habitat monitoring in Italy for the period 2013-2018, whose
collection is in charge to the regional administrations. Data on 124 types of terrestrial
and inland water Habitats present in Italy have been processed in order to assess their
overall conservation status in the Biogeographic Regions of occurrence. The carried out
activity led to the compilation of 278 assessment sheets. The work included a critical
analysis of the data and a broad scientific confrontation aimed at finding
methodologically robust solutions to fill the gaps. The work was structured so as to
guarantee the traceability of the information and to allow the collection of "gray"
literature and scientific articles, phytosociological surveys and unpublished material of
the specialists, composing a substantial pool of data useful for starting a long-term
process to support the next reporting cycles. Cartographic outcomes, associated
databases and additional data used for the assessments will be available online on the
ISPRA Portal as soon as the validation process by the European Commission will be
completed. A freely accessible online archive of phytosociological surveys
representative of the various Annex I Habitats in Italy is being set up within the national
"VegItaly" database, managed by the Italian Society of Vegetation Science, by way of a
dedicated archive named "HAB_IT". Such a long-term vision, oriented to the storage
and enhancement of knowledge, represents an important innovative aspect and a
significant progress towards the construction of an effective monitoring system for the
conservation of Annex I Habitats in Italy
Shedding light on typical species: Implications for habitat monitoring
Habitat monitoring in Europe is regulated by Article 17 of the Habitats Directive, which suggests the use of typical species to assess habitat conservation status. Yet, the Directive uses the term âtypicalâ species but does not provide a definition, either for its use in reporting or for its use in impact assessments. To address the issue, an online workshop was organized by the Italian Society for Vegetation Science (SISV) to shed light on the diversity of perspectives regarding the different concepts of typical species, and to discuss the possible im-plications for habitat monitoring. To this aim, we inquired 73 people with a very different degree of expertise in the field of vegetation science by means of a tailored survey composed of six questions. We analysed the data using Pearson's Chi-squared test to verify that the answers diverged from a random distribution and checked the effect of the degree of experience of the surveyees on the results. We found that most of the surveyees agreed on the use of the phytosociological method for habitat monitoring and of the diagnostic and characteristic species to evaluate the structural and functional conservation status of habitats. With this contribution, we shed light on the meaning of âtypicalâ species in the context of habitat monitoring
Is it the Income Distribution or Redistribution that Affects Growth?
Hervorming Sociale Regelgevin
Il supporto della SISV alla realizzazione di un manuale nazionale per il monitoraggio degli habitat della Direttiva 92/43/EEC in Italia.
A partire dall'entrata in vigore della Direttiva 92/43/EEC, la sorveglianza dello stato di conservazione degli habitat elencati nell'Allegato I ed il relativo monitoraggio periodico a intervalli di sei anni sono diventati un obbligo per tutti i paesi membri dell'UE, in base a quanto previsto negli Articoli 11 e 17. Nel 2011 Ăš stato pubblicato un documento che fornisce le linee guida di riferimento europee per il monitoraggio di habitat e specie (Evans & Arvela 2011). Su questa base metodologica, la SocietĂ Italiana di Scienza della Vegetazione (SISV), avvalendosi di un ampio gruppo di soci esperti, ha avviato un dibattito interno su principi, criteri, parametri e strumenti per il monitoraggio degli habitat di Allegato I e dei tipi di vegetazione in essi rappresentati. Il progetto Ăš stato promosso dal Ministero dell'Ambiente e della Tutela del Territorio e del Mare e coordinato dall'Istituto Superiore per la Protezione e la Ricerca Ambientale, e si trova al momento in una fase prossima alla conclusione. A partire dalla documentazione giĂ prodotta a livello nazionale per gli habitat italiani (Biondi et al., 2009, 2012, 2014; Genovesi et al., 2014), diversi aspetti critici sono stati esaminati attraverso una discussione scientifica ampiamente condivisa. In particolare, sono stati affrontati: gli aspetti legati alla scelta di strumenti adeguati per valutare i parametri area, struttura e funzione, prospettive future; il concetto di "specie tipica"; i metodi di campionamento habitat-specifici appropriati. Il protocollo sviluppato si pone come uno strumento pratico ed efficace, scientificamente valido e in linea con gli standard metodologici internazionali. Il suo utilizzo permetterĂ una raccolta armonizzata di dati su scala nazionale, rendendo possibile una valutazione comparata dello stato di conservazione di ciascun habitat
- âŠ