1,720,989 research outputs found
Good for management, not for conservation: an overview of research, conservation and management of Italian small mammals
Full text linkSmall mammals (Rodentia, Soricomorpha and Erinaceomorpha) play a crucial ecological role for their distribution and importance in food chains, as well as for being considered environmental bioindicators. Thus, they represent excellent models for understanding the evolutionary processes of ecosystems, population dynamics under changing environmental conditions, and habitat vulnerabilities. However, some rodents may help the spread of human diseases and are responsible for impacts on agriculture, forestry, and ecosystems. Consequently, small mammal species are often neglected in conservation biology, and only a few of them are protected according to national and European laws and directives. In this work, we summarize open questions related to Italian small mammals and analyze conservation issues linked to these species. We address research, management and conservation priorities by considering ongoing activities and the novelties as regards the taxonomy and zoogeography. In Italy, 39 native species, including four out of six Italian endemic mammal species and one questioned as native, and 10 alien species are currently included within the category "small mammals". Although several studies revealed that small mammals may be heavily impacted by habitat loss and fragmentation as well as forest management, only three rodents are listed in IUCN red list as "Near Threatened", the remaining being "Least Concern". We suggest that this may be due to the fact that pertinent information, is not translated in assessments in line with those of other taxonomic groups (e.g. bats). Conservation strategies are still inadequate, impacts of alien species still partly unknown or neglected. Thus, wide monitoring projects, ecological studies and general public involvement in conservation effort should be implemented, with the aim to amend national legislation, thus providing native small mammals with adequate protection status
Indagine preliminare, in ambiente GIS, sulle preferenze ambientali di due specie di Anfibi nell’ambito della prima fase del progetto di monitorggio nelle aree protette della Regione Lazio, pp. 128-133.
No full textLong-term, climate change-related shifts in monthly patterns of roadkilled Mediterranean snakes (Hierophis viridiflavus)
No full textEctothermic vertebrates depend on ambient temperatures for their activities. Thus, global warming is expected to influence several aspects of their ecology. Here, we use a >20 year (1990-2011) dataset on monthly numbers of roadkills in an area of central Italy in order to document whether the phenology of a Mediterranean population of Western whip snakes (Hierophis viridiflavus) has changed over time. Annual variation of roadkills was correlated to five climatic variables: (i) mean annual air temperature, (ii) mean February air temperature, (iii) mean July air temperature, (iv) yearly number of rainy days, and (v) number of rainstorm days. Increases in mean annual temperature were positively related to the number of roadkills at the early (February and March) and late (December) phases of above-ground activity, but were negatively related to the number of roadkills during summer (June and July). Intriguingly, we documented a shift in the annual mortality peak over the study period, possibly indicating temporal changes of the mating season due to global warming. Increasing mean air temperatures apparently caused an earlier onset of above-ground activity of snakes and delayed hibernation, but reduced the intensity of snake above-ground activity during the hottest and driest period of the year. Rainfall variables had no impact on snake activity
The italian peninsula hosts a divergent mtDNA lineage of the water vole, Arvicola amphibius s.l., including fossorial and aquatic ecotypes
Full text linkWe characterized eighteen water voles, Arvicola amphibius (s.l.), from five populations along the Italian peninsula by means of mtDNA cytochrome b (Cytb) sequences. The samples included aquatic voles and one fossorial population from northern Italy. The standard karyotype of four voles from one central Italian population was also analysed and was identical to the one found in other populations outside Italy. Phylogenetic analyses, including vole Cytb haplotypes from the entire range, indicated the existence of a wellsupported and highly divergent Italian lineage (4.3%), sister to all the other haplotypes. The fossorial voles are not genetically differentiated from the aquatic voles from a nearby population and belong to the same taxon. Given the high Cytb divergence and the results of previous investigations on allozymes and hybrid fertility, we believe that the Italian population of water voles belongs to a distinct species, Arvicola italicus Savi, 1838, with the type locality near Pisa, although a morphological assessment of the entire skull is necessary to define it
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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