Search results for "35"
showing 10 items of 2413 documents
Zooplankton biodiversity and community structure vary along spatiotemporal environmental gradients in restored peridunal ponds
2015
<p>Zooplankton assemblages in neighboring ponds can show important spatial and temporal heterogeneity. Disentangling the influence of regional versus local factors, and of deterministic versus stochastic processes has been recently highlighted in the context of the metacommunity theory. In this study, we determined patterns of temporal and spatial variation in zooplankton diversity along one hydrological year in restored ponds of different hydroperiod and age. The following hypotheses regarding the assembling of species over time were tested: i) dispersal is not limited in our study system due to its small area and high exposure to dispersal vectors; ii) community dissimilarity among …
Shining castles and humans of metal/floral appearance ? metaphorical language in the Palaiologan romances Kallimachos and Velthandros
2019
About eight centuries after Heliodorus, the Greek novel resurfaced in the twelfth century, in Komnenian Byzantium, and again two centuries later under the Palaiologan dynasty. This latter literary revival was due to the political stability of the imperial Byzantine government, which promoted cultural production, rhetorical education, and patronage networks. Kallimachos and Velthandros, two Palaiologan romances presented as court literature, combine ancient and medieval tropes with rhetorical artistry to blur the boundaries between the artificial and the natural. Castles and objects made of precious metals thus resemble living, natural spaces, and human characters are portrayed in metallurgi…
Combination of aztreonam, ceftazidime–avibactam and amikacin in the treatment of VIM-1 Pseudomonas aeruginosa ST235 osteomyelitis
2021
Abstract We describe a challenging case of patient with metallo-beta-lactamase-producing Pseudomonas aeruginosa sternal osteomyelitis following aortic valve replacement with biological prosthesis. The strain exhibited a multidrug-resistance phenotype carrying the blaVIM-1 gene and belonged to the high-risk clone sequence type ST235. The patient was successfully treated with surgical debridement plus antibiotic therapy with ceftazidime/avibactam, aztreonam, and amikacin. Time-kill curves showed that this triple antibiotic combination at 1 × MIC was strongly synergic after 8 h, achieving 99.9% killing and maintaining this until 48 h.
Hybridization of mouse lemurs: different patterns under different ecological conditions
2011
Abstract Background Several mechanistic models aim to explain the diversification of the multitude of endemic species on Madagascar. The island's biogeographic history probably offered numerous opportunities for secondary contact and subsequent hybridization. Existing diversification models do not consider a possible role of these processes. One key question for a better understanding of their potential importance is how they are influenced by different environmental settings. Here, we characterized a contact zone between two species of mouse lemurs, Microcebus griseorufus and M. murinus, in dry spiny bush and mesic gallery forest that border each other sharply without intermediate habitats…
Polarization Modulation Instability in All-Normal Dispersion Microstructured Optical Fibers With Quasi-Continuous Pump
2019
We report the experimental observation of the polarization modulation instability (PMI) effect in all-normal dispersion (ANDi) microstructured optical fibers (MOFs) with quasi-continuous pumping. The small unintentional birefringence (~10-5), that any realistic non-polarization maintaining MOF exhibits, contributes to this nonlinear effect. PMI can produce two sidebands whose polarization state is orthogonal to the polarization of the pump. In this work, only one type of PMI process is observed, i.e., when the pump is polarized along the slow axis of the fiber and sidebands are generated in the fast axis mode. This PMI process was studied experimentally in two ANDi fibers with different dis…
Tracing the first steps of American sturgeon pioneers in Europe
2008
Abstract Background A Baltic population of Atlantic sturgeon was founded ~1,200 years ago by migrants from North America, but after centuries of persistence, the population was extirpated in the 1960s, mainly as a result of over-harvest and habitat alterations. As there are four genetically distinct groups of Atlantic sturgeon inhabiting North American rivers today, we investigated the genetic provenance of the historic Baltic population by ancient DNA analyses using mitochondrial and nuclear markers. Results The phylogeographic signal obtained from multilocus microsatellite DNA genotypes and mitochondrial DNA control region haplotypes, when compared to existing baseline datasets from extan…
Signals of demographic expansion in Drosophila virilis
2008
Background. The pattern of genetic variation within and among populations of a species is strongly affected by its phylogeographic history. Analyses based on putatively neutral markers provide data from which past events, such as population expansions and colonizations, can be inferred. Drosophila virilis is a cosmopolitan species belonging to the virilis group, where divergence times between different phylads go back to the early Miocene. We analysed mitochondrial DNA sequence variation among 35 Drosophila virilis strains covering the species' range in order to detect demographic events that could be used to understand the present characteristics of the species, as well as its differences …
Understanding the Drivers of the Daily App Rank: The Role of Revenue Models
2015
In this paper, based on data from two major app stores (Apple Store and Google Play), we study the role of several revenue models adopted by developers in the success of an app measured in terms of daily rank.
An empirical analysis of revenue drivers in the mobile app market
2013
Changing commuters’ mobility behaviors of university campuses: environmental and energy comparisons
2021
Governments are required to take proper measures to promote the use of electric and hybrid vehicles and, more generally, to push people towards sweeter modalities including walking and biking. To reach such tight and challenging goals, local institutions should be deeply involved, and universities among them. The promotion of sustainable mobility practices among commuter students must be considered indeed an effective contribution to facilitating the transition towards greener cities. On purpose, students of the University of Palermo that daily commute from their residences to the campus are considered here. These commuters, in fact, mainly adopt traditional polluting transportation means. …