5,712 research outputs found
Biometric characterization of the Red-legged Partridges Alectoris rufa of northwestern Italy
The biometrics of the Red-legged Partridge Alectoris rufa has been relatively well studied in the western part of its distribution range (Iberian Peninsula and France), especially due to the available large hunting bag samples. Conversely, the Italian population is poorly characterized. We analysed a sample of 254 live birds trapped and ringed in the northern Apennines (province of Alessandria, northwestern Italy), by measuring body mass and the length of wing, eighth primary, tail, tarsus and bill. We found significant differences in some biometric measurements between sex and age classes. A subsample of birds (n = 112) was genetically tested for introgressive hybridization with A. chukar, an introduced species, showing that 16.1 % of free-living partridge are hybrid individuals. When we analysed separately "pure"and "introgressed"birds we found only small biometric differences in body mass of adult males. Finally, our results were compared with the biometry of other populations from the whole natural range of the species (France, Spain and Portugal) showing a negative biometric trend of wing length from westernmost to southeastern birds of the range. Introgressed birds found in the studied population were not easily distinguishable with biometric criteria from pure A. rufa rufa, so genetic analysis is highly recommended when planning reintroductions or restocking
Le api svelano il mistero delle fonti di emissione di particolato inquinante
Si tratta di una ricerca che è durata due anni, ed è stata pubblicata sul numero di luglio 2015 della Rivista scientifica internazionale Plos One. Gli autori: Ilaria Negri, Marco Pellecchia (Koiné - Consulenze Ambientali S.n.c., Parma, Italy), Christian Mavris (Department of Earth Sciences, Natural History Museum, London, United Kingdom), Gennaro Di Prisco, Emilio Caprio (Dipartimento di Agraria, Laboratorio di Entomologia E. Tremblay, Università degli Studi di Napoli Federico II, Portici - Napoli). Nello studio scientifico i ricercatori dimostrano che le api si comportano anche come “campionatori” attivi di particolato atmosferico, i cosiddetti
PM (dall’inglese “Particulate Matter”), di cui sono ricche le nostre città come troppo spesso avvertono i dati dell’Agenzia Regionale di Protezione dell’Ambiente (ARPA). Dice che l’Iglesiente (Iglesias, Sardegna) è inquinato, fortemente contaminato da metalli pesanti come il piombo e il bario. E svela poi che la salute di chi ci vive potrebbe essere compromessa, se non lo è già, anche dall’alta concentrazione di ferro, silicio e alluminio. Rivela ancora, con scientifica precisione, da dove provengono le micro particelle di queste impercettibilissime polveri: dalle miniere dell’Iglesiente e dalle industrie di Portovesm
Honey Bees (Apis mellifera, L.) as Active Samplers of Airborne Particulate Matter
© 2015 Negri et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. [CC by 4.0] The attached file is the published version of the article
Random and Dynamical Calibration for Air Quality Measurement Instruments
In questo lavoro si cerca di ricavare il valore della concentrazione nell’aria delle polveri sottili, dal diametro minore di 2.5 micron (PM2.5), da quello delle polveri di diametro fino a 10 micron (PM10). Il monitoraggio di quest‘ultima è effettuato ormai da anni in tutti i paesi occidentali e costituisce uno dei parametri per la valutazione della qualità dell’aria. Ciò non accade invece per le PM2.5, che risultano anche più pericolose per la salute dei soggetti più deboli e più a rischio di malattie cardio-polmonari. Tuttavia, dal momento che la concentrazione delle PM2.5 riguarda una percentuale che varia dal 60% al 90% delle PM10, il problema può essere affrontato con i modelli di taratura stocastica dinamica in cui il valore delle PM2.5 è considerata la misura incognita, da ricavare partendo da un campione di taratura
On the Goodness-of-Fit Tests for Some Continuous Time Processes
We present a review of several results concerning the construction of the
Cramer-von Mises and Kolmogorov-Smirnov type goodness-of-fit tests for
continuous time processes. As the models we take a stochastic differential
equation with small noise, ergodic diffusion process, Poisson process and
self-exciting point processes. For every model we propose the tests which
provide the asymptotic size and discuss the behaviour of the power
function under local alternatives. The results of numerical simulations of the
tests are presented.Comment: 22 pages, 2 figure
Little owl (Athene noctua): nuclear and mitochondrial DNA analysis reveals divergence of soutwestern and central european subspecies
We utilized mitochondrial and nuclear DNA to study the phylogeography of little owls (Athene
noctua) across Europe. Data from 326 individuals distributed among 22 sites were used to assess
geographical distribution of the European subspecies, i.e., the widely accepted vidalii, noctua and
indigena, and the questioned sarda-species. On the basis of the sequences of two mtDNA markers
(CRI D-Loop 494 bp and COI 679 bp), we found a major difference between a first haplogroup,
distributed in the North-West (from Iberia to Denmark and Czech Republic) and three other
clades, distributed in the South-Eastern part of the study area. In particular we found a second
group distributed in the Balkans and a third located in Sardinia, while in Italy there was a mixture
between a fourth haplogroup of South-Italy and both the North-West and the Balkan clades. All
individuals sampled in Sardinian differed clearly from other haplogroups. The combined analyses
of the 13 nuclear microsatellite loci corroborated these results. Both mitochondrial and nuclear
markers showed that interaction across contact zones generate a mixture of genotypes not only in
Italy, but also in Central Europe. The apparent position of the contact zones differs substantially
from the subspecies distribution reported in literature. DNA data are consistent with the
phylogeographic hypothesis that this species survived the Pleistocene glaciations in three major
refugia located in Iberia, South Italy, and the Balkans. Expansion patterns indicate that little owls
from the Iberian refugium were the predominant source of postglacial colonization of northern
Europe, while expansion out of South-Italy and Balkans had more limited effects
Selective imitation impairments differentially interact with language processing
Whether motor and linguistic representations of actions share common neural structures has recently been the focus of an animated debate in cognitive neuroscience. Group studies with brain-damaged patients reported association patterns of praxic and linguistic deficits whereas single case studies documented double dissociations between the correct execution of gestures and their comprehension in verbal contexts. When the relationship between language and imitation was investigated, each ability was analysed as a unique process without distinguishing between possible subprocesses. However, recent cognitive models can be successfully used to account for these inconsistencies in the extant literature. In the present study, in 57 patients with left brain damage, we tested whether a deficit at imitating either meaningful or meaningless gestures differentially impinges on three distinct linguistic abilities (comprehension, naming and repetition). Based on the dual-pathway models, we predicted that praxic and linguistic performance would be associated when meaningful gestures are processed, and would dissociate for meaningless gestures. We used partial correlations to assess the association between patients' scores while accounting for potential confounding effects of aspecific factors such age, education and lesion size. We found that imitation of meaningful gestures significantly correlated with patients' performance on naming and repetition (but not on comprehension). This was not the case for the imitation of meaningless gestures. Moreover, voxel-based lesion-symptom mapping analysis revealed that damage to the angular gyrus specifically affected imitation of meaningless gestures, independent of patients' performance on linguistic tests. Instead, damage to the supramarginal gyrus affected not only imitation of meaningful gestures, but also patients' performance on naming and repetition. Our findings clarify the apparent conflict between associations and dissociations patterns previously observed in neuropsychological studies, and suggest that motor experience and language can interact when the two domains conceptually overla
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