962 research outputs found
Plant Conservation Centres in Sicily: The ‘Valle Maria’ Regional Centre (Godrano, Palermo) and the case study of the rare Centaurea erycina (Asteraceae).
The role of the ‘Valle Maria’ Regional Centre and its activity in plant conservation thank to the collaboration with the University of Palermo, Dept. STEBICEF is discussed. The case study on propagation of Centaurea erycina, a narrow Sicilian endemic is presented
A Positron Implantation Profile Estimation Approach for the PALS Study of Battery Materials
Positron annihilation spectroscopy is a powerful probe to investigate the interfaces in materials relevant for energy storage such as Li-ion batteries. The key to the interpretation of the results is the positron implantation profile, which is a spatial function related to the characteristics of the materials forming the battery. We provide models for the positron implantation profile in a cathode of a Li-ion battery coin cell. These models are the basis for a reliable visualization of multilayer geometries and their interfaces in thin cathodes of lithium-ion batteries
PRIMI DATI SUGLI INNESTI DI ABIES NEBRODENSIS (LOJAC.) MATTEI ESEGUITI SU ABETI ESOTICI NELL\u2019AREA DI INDIGENATO (MADONIE)
C2 = PRIMI DATI SUGLI INNESTI DI ABIES NEBRODENSIS (LOJAC.) MATTEI
ESEGUITI SU ABETI ESOTICI NELL\u2019AREA DI INDIGENATO (MADONIE)
R. SCHICCHI, P. BONOMO, M. CANDORE, G. DI NOTO, A. PUCCI, F. TRAPANI, P. MARINO
Dipartimento di Biologia Ambientale e Biodiversit\ue0 dell'Universit\ue0, via Archirafi 38, 90123 Palermo (I)
[email protected]
Abies nebrodensis \ue8 una specie endemica relitta, gravemente minacciata di estinzione, la cui popolazione naturale \ue8 costituita da 30 individui distribuiti discontinuamente in una piccola area del territorio di Polizzi Generosa, all\u2019interno del Parco naturale delle Madonie in Sicilia. La minaccia di estinzione \ue8 dovuta, oltre all'esiguit\ue0 della popolazione, al ridotto numero di piante mature (ventiquattro) e al pericolo di inquinamento genetico incombente. A partire dall\u2019inizio degli anni \u201880 del secolo scorso, infatti, sono stati introdotti nella vicinanze dell\u2019area di indignato individui di abeti esotici (Abies alba Mill., A. cephalonica Loudon, e A. nordmanniana (Stefen) Spach) che, avendo raggiunto la maturit\ue0 sessuale, potrebbero mettere a rischio l\u2019integrit\ue0 genetica della progenie dell\u2019abete locale (Raimondo & Schicchi, 2005). Nell\u2019ambito del progetto \u201cConservazione di Abies nebrodensis e ripristino delle torbiere di Geraci Siculo\u201d, in corso di attuazione da parte dell\u2019Ente Parco delle Madonie, del Dipartimento di Biologia ambientale e Biodiversit\ue0 di Palermo e di altri partners locali, un\u2019azione di salvaguardia prevede l\u2019innesto degli abeti esotici con marze di A. nebrodensis, valorizzando la positiva esperienza effettuata con il progetto Life Natura (1). A tal fine, nel periodo compreso tra la terza decade di aprile e la seconda decade di maggio sono stati effettuati circa 350 innesti in contrada Comunello, nel territorio di Isnello. Le marze sono state prelevate da individui maturi di A. nebrodensis di oltre 30 anni di et\ue0, introdotti nelle opere di ripopolamento che, in seguito ai risultati delle analisi genetiche, sono geneticamente correlati agli esemplari della popolazione naturale. Gli innesti sono stati eseguiti a spacco ma soprattutto a corona, previa capitozzatura dei soggetti di A. alba e A. cephalonica, a un\u2019altezza di circa 2 m per evitare possibili danneggiamenti da parte del bestiame. Nei soggetti sono stati, comunque, rilasciati temporaneamente alcuni palchi che, continuando a svolgere le normali funzioni vitali, agevoleranno l\u2019attecchimento delle marze. Queste ultime sono state opportunamente sagomate e inserite tra la corteccia e il legno sia nel fusto capitozzato che in alcuni rami laterali. Esse sono state tenute strettamente aderenti ai soggetti tramite nastro adesivo e protette da due sacchetti, rispettivamente di polietilene e di carta, per creare condizioni micro-climatiche ottimali alla sopravvivenza delle marze. Dalla terza decade di maggio \ue8 iniziato, con cadenza settimanale, il monitoraggio degli innesti e la foratura, ove necessario, del sacchetto di plastica per eliminare l\u2019umidit\ue0 in eccesso. Dopo 40 giorni \ue8 stato possibile constatare che oltre il 90% degli innesti \ue8 attecchito. Anche alcuni innesti eseguiti a scopo sperimentale su Pseudotsuga menziesii Franco sono vitali. Durante la fine di luglio e agosto si prevede una graduale scopertura delle marze. Gli esiti di questa azione, tuttavia, potranno essere valutati compiutamente all\u2019inizio della prossima primavera. La tecnica dell\u2019innesto riveste notevole importanza poich\ue9 permette di eliminare o ridurre una delle minacce pi\uf9 consistenti a carico della popolazione naturale di A. nebrodensis, trasformando la stessa in un punto di forza nell\u2019ambito della strategia di conservazione della specie. Essa, infatti, potr\ue0 contribuire a incrementare la popolazione dell\u2019endemico A. nebrodensis, valorizzando come portainnesti piante che se non abbattute costituirebbero un serio pericolo per la conservazione dell\u2019abete delle Madonie.
Raimondo F. M., Schicchi R., 2005. Rendiconto sul progetto LIFE Natura n\ub0 LIFE2000NAT/IT/7228 \u201cConservazione in situ ed ex situ di Abies nebrodensis (Lojac.) Mattei\u201d. Tipolitografia Luxograph, Palermo
The monumental olive trees as biocultural heritage of mediterranean landscapes: The case study of sicily
Monumental olive trees, with their longevity and their remarkable size, represent an important information source for the comprehension of the territory where they grow and the human societies that have kept them through time. Across the centuries, olive trees are the only cultivated plants that tell the story of Mediterranean landscapes. The same as stone monuments, these green monuments represent a real Mediterranean natural and cultural heritage. The aim of this paper is to discuss the value of monumental trees as “biocultural heritage” elements and the role they play in the interpretation of the historical stratification of the landscape. We present the results of a survey of the most significant olive trees growing in Sicily. The selection was based on the “monumentality” aspects of trees, taking into account dendrometric parameters and environmental contexts. The collected dataset constitutes a heterogeneous sample of 367 specimens of considerable size that, in some cases, reach a circumference of about 19 m. Starting from the data presented here, the whole Sicilian territory shows a historical relationship between human and olive. The presence of these plant monuments is, therefore, evidence of long‐term, often centennial, landscapes as a result of sustainable use of the territory
Positronium cooling at cryogenic temperature for advanced experiments
New Ps spectroscopy measurements, formation of antihydrogen for antimatter-matter comparison experiments, production of Ps beams require the efficient production of cooled positronium in vacuum. At present the most efficient positron-positronium converters are silica based ordered or disordered porous materials, in which formed Ps decreases its kinetic energy by collisional cooling. Recently new positron-positronium converters based on oxidized nanochannels in silicon were found to be very promising because of the tunability of the nanochannel size, which allows to overcome the limits imposed to the Ps cooling by the quantum confinement. With these converters, Ps with temperatures as low as 150 K was detected in vacuum by a TOF apparatus. The Ps formation, quantum confinement, collisional cooling and emission into vacuum from nanochanneled silicon will be discussed in light of recent results
Successful control of an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K.\ua0pneumoniae sequence type 258 in a neonatal intensive care unit, Italy
This article reports an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) sequence type (ST) 258 in a neonatal intensive care unit (NICU) in Palermo, Italy. KPC-Kp ST258 was detected by an active surveillance culture programme. Between 18th September and 14th November 2012, KPC-Kp was isolated from 10 out of 54 neonates admitted in the outbreak period. No cases of infection were recorded. Male sex was associated with colonization, whereas administration of ampicilline-sulbactam plus gentamicin was protective. Infection control interventions interrupted the spread of KPC-Kp without the need to close the NICU to new admissions. (C) 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved
Quantum view of Li-ion high mobility at carbon-coated cathode interfaces
: Lithium-ion batteries (LIBs) are among the most promising power sources for electric vehicles, portable electronics and smart grids. In LIBs, the cathode is a major bottleneck, with a particular reference to its low electrical conductivity and Li-ion diffusivity. The coating with carbon layers is generally employed to enhance the electrical conductivity and to protect the active material from degradation during operation. Here, we demonstrate that this layer has a primary role in the lithium diffusivity into the cathode nanoparticles. Positron is a useful quantum probe at the electroactive materials/carbon interface to sense the mobility of Li-ion. Broadband electrical spectroscopy demonstrates that only a small number of Li-ions are moving, and that their diffusion strongly depends on the type of carbon additive. Positron annihilation and broadband electrical spectroscopies are crucial complementary tools to investigate the electronic effect of the carbon phase on the cathode performance and Li-ion dynamics in electroactive materials
An improved method on stimulated T-lymphocytes to functionally characterize novel and known LDLR mutations.
The main causes of familial hypercholesterolemia (FH) are mutations in LDL receptor (LDLR) gene. Functional studies are necessary to demonstrate the LDLR function impairment caused by mutations and would be useful as a diagnostic tool if they allow discrimination between FH patients and controls. In order to identify the best method to detect LDLR activity, we compared continuous Epstein-Barr virus (EBV)-transformed B-lymphocytes and mitogen stimulated T-lymphocytes. In addition, we characterized both novel and known mutations in the LDLR gene. T-lymphocytes and EBV-transformed B-lymphocytes were obtained from peripheral blood of 24 FH patients and 24 control subjects. Functional assays were performed by incubation with fluorescent LDL followed by flow cytometry analysis. Residual LDLR activity was calculated normalizing fluorescence for the mean fluorescence of controls. With stimulated T-lymphocytes we obtained a better discrimination capacity between controls and FH patients compared with EBV-transformed B-lymphocytes as demonstrated by receiver operating characteristic (ROC) curve analysis (the areas under the curve are 1.000 and 0.984 respectively; P < 0.0001 both). The characterization of LDLR activity through T-lymphocytes is more simple and faster than the use of EBV-transformed B-lymphocytes and allows a complete discrimination between controls and FH patients. Therefore the evaluation of residual LDLR activity could be helpful not only for mutation characterization but also for diagnostic purposes
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