422 research outputs found
Last tesserae of a fading mosaic: floristic census and forest vegetation survey at Parche di Bilello (south-western Sicily, Italy), a site needing urgent protection measures.
This paper illustrates the botanic heritage of Parche di Bilello, a site located in the municipality of Castelvetrano. The study area hosts several woodland fragments dominated by Olea europaea var. sylvestris, Quercus suber and Quercus ilex, respectively. According to historical data, these nuclei represent the last remnants of an open forestland which covered a much wider coastal area between Mazara del Vallo and Sciacca until the end of Middle Age. Phytosociological relevés were focused on these forest nuclei, probably the most representative of south-western Sicily, which correspond to three habitats included in the 92/43 EEC Directive (9320, 9330 and
9340, respectively) and represent the final stage of three different edaphic series. Wild olive forests probably dominated on sandy calcareous soils, holm oaks prevailed on steep calcareous and N-exposed slopes. In contrast, cork oaks mostly occurred on sandy subacid soils issuing from pedogenetic processes on palaeodunes. Moreover, field surveys allowed to list 331 vascular plant taxa. Among them, Linaria multicaulis subsp. humilis, Orobanche balsensis and Serapias orientalis subsp. siciliensis are new to Trapani Province. Detailed information on the current distribution and the synecology of several plant taxa of high biogeographic and conservation interest is also provided. The study site also hosts one habitat of priority interest (6220, i.e. xerophilous Mediterranean perennial grasslands and annual swards) and two species protected by international laws, i.e. the orchid Ophrys lunulata and the lichen Teloschistes chrysophthalmus. Considering the high value of its natural heritage, this territory deserves the adoption of more effective protection measures. For this reason the authors recommend its inclusion as a new Site of Community Interest within the Sicilian Natura 2000 network
Measuring the quality of teacher-child interaction in autistic disorder
The teacher-child relationship fulfils critical functions for the well being of the child, affecting emotive development, academic achievements, behavioral conducts and relationships with peers. The goal of the presented study is to compare the perceptions of
the class teacher and of the support teacher concerning their relationship with subjects with autistic spectrum disorders (ASD; N=14; Mean age =90.07 months; SD=19.36) and with children of the control group (4 classmates per every subject of the experimental group, for a total of 56 pupils, Mean age = 80.36 months; SD=18.33). The perception by the teacher of the class, concerning the relationship with children with ASD, is
characterized by higher levels of Conflict, and lower levels of Closeness, if compared with perceptions about the relationship with children of the control group (Conflict: t=-3.317; df= 14.931; p<0.01; Closeness: t= 5.638; df = 65; p < 0.001). The perception of the two teachers only correlates with regards to the Conflict dimension (r=0.769; p < 0.01). In reference to the child's adaptive skills only the social skills scale correlates with the
Closeness. This is true in the perception of the support teacher (r=0.598; p<0.05). Finally, we take into account how the perception of the relationship relates with the socio-personal
and professional data of the teachers and with the social features of the children
The effects of post-pasture woody plant colonization on soil and aboveground litter carbon and nitrogen along a bioclimatic transect.
We investigated the effects of woody plant colonization of abandoned pastures
on soil and litter organic carbon (C) stocks and nitrogen (N) content along a
bioclimatic transect in a semi-arid environment (Sicily, Italy). Soil samples
were taken in three successional stages (grazed pasture, shrubland, forest)
within each of three bioclimates (supramediterranean - \u201csupra\u201d, mesomediterranean
- \u201cmeso\u201d, thermomediterranean - \u201cthermo\u201d). Organic C and N in litter
and soil (0-10 cm and 10-30 cm depth) were determined, as well as soil bulk
density. Especially at 0-10 cm depth, changes in C and N contents along successional
stages differed among bioclimates. Soil organic carbon (SOC) stock
decreased from pasture to shrubland and increased from shrubland to forest in
\u201csupra\u201d, increased from pasture to shrubland and then remained stable in
\u201cthermo\u201d, and was stable in \u201cmeso\u201d. Soil C/N ratio decreased with succession
in \u201csupra\u201d, showed no significant trend in \u201cmeso\u201d, and increased with succession
in \u201cthermo\u201d. Litter C stock increased with succession in \u201cmeso\u201d, increased
from pasture to shrubland and decreased from shrubland to forest in
\u201cthermo\u201d, and increased from pasture to shrubland and then remained stable
in \u201csupra\u201d. Litter C/N ratio increased in \u201cthermo\u201d and \u201csupra\u201d from pasture to
shrubland and from shrubland to forest, but did not change significantly with
succession in \u201cmeso\u201d. The different trends in SOC among bioclimates may be
caused by changes in the importance of litter input, litter decay rate and mineralization.
Successional changes in \u201cmeso\u201d and \u201csupra\u201d appeared to be most
affected by litter quality, while those in \u201cthermo\u201d appeared to be strongly influenced
by limited litter decay due to low soil moisture and high temperature
The inhomogeneous mechanical behaviour of Ascending Thoracic Aortic Aneurism (ATAA)
Surgical management of ascending thoracic aortic aneurysms (aTAAs) relies on maximum diameter,
growth rate, and presence of connective tissue disorders. The surgical decision however is often
not considering that dissection and rupture do occur in patients who do not meet criteria for surgical
repair [1,2]. In this study the authors aim to investigate the mechanical properties of aTAAs to be
implemented in computational biomechanics models for a preclinical risk evaluation. Additionally,
in some recent studies, some data about the biomechanical properties of the aTAAs have been reported
[3], but without any relation to bicuspidal or tricuspidal aTAA. The aim of this study was to
investigate aTAA mechanical properties using a biaxial system to compare the circumferential and
axial stress-strain relations for bicuspidal and tricuspidal aTAAs
C4BQ0: a genetic marker of familial HCV-related liver cirrhosis.
Source
Department of Medicine and Pneumology, V Cervello Hospital, Via Trabucco 180, 90146 Palermo, Italy. [email protected]
Abstract
BACKGROUND AND METHODS:
Host may have a role in the evolution of chronic HCV liver disease. We performed two cross-sectional prospective studies to evaluate the prevalence of cirrhosis in first degree relatives of patients with cirrhosis and the role of two major histocompatibility complex class III alleles BF and C4 versus HCV as risk factors for familial clustering.
FINDINGS:
Ninety-three (18.6%) of 500 patients with cirrhosis had at least one cirrhotic first degree relative as compared to 13 (2.6%) of 500 controls, (OR 7.38; CI 4.21-12.9). C4BQ0 was significantly more frequent in the 93 cirrhotic patients than in 93 cirrhotic controls without familiarity (Hardy-Weinberg equilibrium: chi2 5.76, P = 0.016) and in 20 families with versus 20 without aggregation of HCV related cirrhosis (29.2% versus 11.3%, P = 0.001); the association C4BQ0-HCV was found almost only in cirrhotic patients with a family history of liver cirrhosis.
CONCLUSIONS:
Our studies support the value of C4BQ0 as a risk indicator of familial HCV related cirrhosis
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