Search results for " pattern"
showing 10 items of 2245 documents
Past cover modulates the intense and spatially structured natural regeneration of woody vegetation in a pastureland
2020
Made available in DSpace on 2020-12-12T02:34:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 Università degli Studi di Palermo Ministero dell’Istruzione, dell’Università e della Ricerca Vegetation natural regeneration after agricultural abandonment is changing the landscape patterns in many areas worldwide. However, the expansion rate, spatio-temporal dynamics, and the role of past vegetation cover in shaping such patterns are still barely quantified in fine and meso scales. Here, we aim to quantify the expansion rate and assess the spatio-temporal patterns and the effects of past cover on natural woody vegetation cover increase. We sampled woodland and shrubland cover from …
Crostacei Anfipodi associati ai reef di Sabellaria alveolata (Annelida: Sabellariidae) del Canale di Sicilia (Mar Mediterraneo)
2015
We describe diversity and patterns of spatial distribution of the amphipod fauna associated with reefs of the polychaete Sabellaria alveolata (L.) in the Sicily Strait. Samples were collected in June 2013, at three localities. Amphipod assemblages appeared homogeneous in the study area with variability increasing with decreasing spatial scale of observation. Jassa ocia (Bate) and Gammaropsis ulrici Krapp-Schickel & Myers characterized the studied assemblages.
Drinking pattern matters: effects on maternal care and offspring vulnerability to alcohol in rats
2015
Alcohol drinking during pregnancy and post-partum period is a major concern because of the persistent neurobehavioral deficits in the offspring, which include increased vulnerability to substance abuse (1). The intermittent pattern of alcohol consumption induces higher drinking levels and deeper neurobiological changes in addiction-related brain regions, with respect to traditional free-access paradigms in male rats (2, 3). Nevertheless, no studies investigated on the effects of the drinking pattern on female subjects during pregnancy and perinatal time. To this aim, this study explored the consequences of continuous vs. intermittent drinking pattern on maternal behaviour and on offspring v…
Metilazione del DNA in artrite reumatoide
2005
Lo stato di metilazione del DNA genomico e del gene PTHrP è stato valutato con tecniche molecolari e citogenetiche in artrite reumatoide (AR), patologia autoimmune caratterizzata anche da alta incidenza di linfomi e da ipercalcemia per overespressione del gene PTHrP. La metilazione del DNA, infatti, ha un ruolo critico nello sviluppo delle malattie neoplastiche; il gene PTHrP avendo tre promotori uno dei quali contiene un’isola CpG è un buon candidato per la deregolazione da alterato pattern di metilazione locale. Le indagini sulla metilazione genomica, condotte su DNA estratto da sangue periferico di pazienti e di donatori e amplificato in reazioni di Methylation-Sensitive Arbitrarily Prim…
Ac-locking of thermally-induced sine-Gordon breathers
2023
A complete framework for exciting and detecting thermally-induced, stabilized sine-Gordon breathers in ac-driven long Josephson junctions is developed. The formation of long-time stable breathers locked to the ac source occurs for a sufficiently high temperature. The latter emerges as a powerful control parameter, allowing for the remarkably stable localized modes to appear. Nonmonotonic behaviors of both the breather generation probability and the energy spatial correlations versus the thermal noise strength are found. The junction's resistive switching characteristics provides a clear experimental signature of the breather.
Role of the Colored Noise in Spatio-Temporal Behavior of Two Competing Species
2005
We study the spatial distributions of two randomly interacting species, in the presence of an external multiplicative colored noise. The dynamics of the ecosystem is described by a coupled map lattice model. We find a nonmonotonic behavior in the formation of large scale spatial correlations as a function of the multiplicative colored noise intensity. This behavior is shifted towards higher values of the noise intensity for increasing correlation time of the noise.
Extinction of selected micromammal taxa during the Middle Pleistocene of Europe.
2014
Multi-scale dissolution events in Western-Tethyan peritidal carbonates close to the Triassic/Jurassic boundary
2015
The stratigraphical and sedimentological study of uppermost Triassic-lowermost Jurassic sections of peritidal carbonates, in north-western Sicily, allows to differentiate multi-scale dissolution events that affected the carbonate platform interior during the uppermost Rhaetian. The Triassic cycles show extensive phenomena of stratabound dissolution that can be differentiated in three main types: vug, moldic and “spongy-like”. The dissolution horizons are particularly concentrated in the subtidal members of cycles. The creation of different type of porosity seems to be mainly controlled by the textural characters of the host-rock. In particular the cm-scale bioturbation in muddy sediments, p…
The Impact of Climate, Resource Availability, Natural Disturbances and Human Subsistence Strategies on Sicilian Landscape Dynamics During the Holocene
2022
This paper presents a multidisciplinary summary of the most recent discoveries and hypotheses concerning factors driving the human subsistence economy and landscape shaping in Sicily during the Holocene. A number of scientific papers have recently pointed out the key role played by paleogeography, resource (water, food) availability and natural disturbances (volcanic eruptions, tsunamis) in local human activities. Modern anthropology and archaeology increasingly use biological remains (e.g. soils, bones, wood, plant macroremains, pollen) to better understand how human communities managed to survive and spread. Likewise, refined reconstructions of past human demographic fluxes and socio-econ…