Search results for "CLASSIFICATION"
showing 10 items of 29475 documents
Seroprevalence of and risk factors for Leishmania seropositivity in a sample population of Western Sicily (Italy)
2013
Background: Leishmania is a vector-borne parasite responsible for significant morbidity and mortality worldwide. The aim of this study was to assess the prevalence of and risk factors for Leishmania infantum seropositivity in a sample of Sicilian population.Methods: A total of 260 subjects were interviewed using a standardized questionnaire and requested for an venous blood sample.Results: Overall, 36 subjects (13.8%) were seropositive against L. infantum with a statistically significant higher prevalence of positivity in older subjects (p=0.04). After adjustment for age, a higher risk for Leishmania seropositivity was found in subjects who had pets living outdoors and untreated with anti-p…
Microbiota of sliced cooked ham packaged in modified atmosphere throughout the shelf life
2019
Abstract Fourteen lots of cooked ham in modified atmosphere packaging (CH) were analyzed within a few days from packaging (S) and at the end of the shelf-life (E), after storage at 7 °C to simulate thermal abuse. Five more lots, rejected from the market because spoiled (R), were included in the study. Quality of the products was generally compromised during the shelf life, with only 4 lots remaining unaltered. Analysis of 16S rRNA gene amplicons resulted in 801 OTUs. S samples presented a higher diversity than E and R ones. At the beginning of the shelf life, Proteobacteria and Firmicutes dominated the microbiota, with Acinetobacter, Brochothrix, Carnobacterium, Lactobacillus, Prevotella, P…
The effectiveness of pre- and post-zygotic barriers in avoiding hybridization between two snapdragons (Antirrhinum L.: Plantaginaceae)
2014
Reproductive barriers play an important role in the maintenance of species boundaries. However, to date, few studies have provided a detailed analysis of reproductive isolation barriers between species or examined their importance in maintaining species identity. This is the first detailed study into pre- and post-zygotic reproductive isolation barriers in Antirrhinum, based on a mixed population with two species that rarely co-occur. The study revealed that pollinator constancy and preference and poor hybrid seed viability were the most important reproductive isolating mechanisms. Reproductive isolation was practically complete by both pre- and post-zygotic barriers. Average pre-zygotic is…
On the identity of Ischyropsalis dentipalpis Canestrini, 1872 and description of Ischyropsalis lithoclasica sp. n. (Opiliones: Ischyropsalididae)
2010
Ischyropsalis dentipalpis Canestrini, 1872 is re-defined, and a neotype from the type locality in the Aosta Valley, Italy, is assigned. I. helvetica Roewer, 1916 (sensu Martens 1978) is shown to be conspecific and therefore is synonymised with I. dentipalpis. A population from Bergamo Province, Italy, formerly assigned to I. dentipalpis (sensu Martens 1978), is here regarded as a different species and described under the name Ischyropsalis lithoclasica sp. n. Discrimination of males is possible by genital characters and by the shape of the cheliceral and pedipalpal apophyses. Females are distinguished by peculiarities of cheliceral spination. The distribution of I. lithoclasica n. sp. is al…
Analysis of the Sponge [Porifera] Gene Repertoire: Implications for the Evolution of the Metazoan Body Plan
2003
Sponges [phylum Porifera] form the basis of the metazoan kingdom and represent the evolutionary earliest phylum still extant. Hence, as living fossils, they are the taxon closest related to the hypothetical ancestor of all Metazoa, the Urmetazoa. Until recently, it was still unclear whether sponges are provided with a defined body plan. Only after the cloning, expression and functional studies of characteristic metazoan genes, could it be demonstrated that these animals comprise the structural elements which allow the sponge cells to organize themselves according to a body plan. Adhesion molecules involved in cell—cell and cell—matrix interactions have been identified. Among the cell—cell a…
Emersion generalisee intra-maastrichtienne de la plate-forme de Gavrovo-Tripolitza (Grece); effets sur les populations de foraminiferes Rhapydioninin…
2001
Abstract The reliability of biostratigraphic correlations in neritic carbonate platforms is often questioned because the benthic fauna on which biozonation is based are particularly sensitive to environmental change. It is crucial to know whether a population change corresponds strictly to a facies change. Conversely, there arise the questions of determining how populations are renewed over time and how new species appear even if facies associations remain unchanged. This is the case with the Gavrovo-Tripolitza zone of Greece, an isolated shallow carbonate platform surrounded by two oceanic domains (Pindos-Olonos Zone and Ionian Zone). The absence or scarcity of faunas generally used in Upp…
Activity and role of the enchytraeid worm Cognettia sphagnetorum (Vejd.) (Oligochaeta: Enchytraeidae) in organic and mineral forest soil
2003
Summary Site preparation following clear felling of coniferous forest creates a mosaic of different kinds of habitats for soil decomposers, ranging from bare mineral soil to thick layers of organic soil and felling residues. To study whether the impact of enchytraeids on nutrient mineralisation processes is different in residues, organic layer, and mineral soil, a microcosm experiment was conducted in the laboratory. Microcosms contained mineral soil (sand) alone or with soil organic layer (humus and F-layer materials) and spruce needles, either separately or together. Enchytraeids (Cognettia sphagnetorum) were introduced to the half of the microcosms. Numbers of enchytraeids, their gut con…
Size distribution of Daphnia longispina in the vertical profile
1997
D. longispina of the meromictic lake El Tobar is a round-headed form. It never has a helmet, but in summer a small proportion of immature individuals (0.9–1.2 mm females and males) have one or two neck teeth. The size structure of this Daphnia population, as well as the vertical distribution and migration of different size-classes, were studied in September and November of 1991 and April of 1992. The large variation in mean size and size at first reproduction, as well as the occurrence of different patterns of vertical migration are interpreted as responses to different predator situations. At the end of April, when Daphnia mortality by visually hunting predators is dominating, a typical no…
Assessment of domestic water consumption in Valencia city through fuzzy-set qualitative comparative analysis
2021
The influence of quantitative and qualitative population conditions needs to be jointly considered in the assessment of urban water demand. Through fuzzy-set qualitative comparative analysis (fsQCA...
Long-term monitoring reveals topographical features and vegetation explain winter habitat use of an Arctic rodent
2021
AbstractCollapsing lemming cycles have been observed across the Arctic, presumably due to global warming creating less favorable winter conditions. The quality of wintering habitats, such as depth of snow cover, plays a key role in sustaining population dynamics of arctic lemmings. However, few studies so far investigated habitat use during the arctic winter. Here, we used a unique long-term time series to test whether lemmings are associated with topographical and vegetational habitat features for their winter refugi. We examined yearly numbers and distribution of 22,769 winter nests of the collared lemming Dicrostonyx groenlandicus from an ongoing long-term research on Traill Island, Nort…