1,697 research outputs found
An integrated analysis of micro- and macro-habitat features as a tool to detect weather-driven constraints: a case study with cavity nesters
The effects of climate change on animal populations may be shaped by habitat characteristics at both micro- and macro-habitat level, however, empirical studies integrating these two scales of observation are lacking. As analyses of the effects of climate change commonly rely on data from a much larger scale than the microhabitat level organisms are affected at, this mismatch risks hampering progress in developing understanding of the details of the ecological and evolutionary responses of organisms and, ultimately, effective actions to preserve their populations. Cavity nesters, often with a conservation status of concern, are an ideal model because the cavity is a microenvironment potentially different from the macroenvironment but nonetheless inevitably interacting with it. The lesser kestrel (Falco naumanni) is a cavity nester which was until recently classified by as Vulnerable species. Since 2004, for nine years, we collected detailed biotic and abiotic data at both micro- and macro-scales of observation in a kestrel population breeding in the Gela Plain (Italy), a Mediterranean area where high temperatures may reach lethal values for the nest content. We show that macroclimatic features needed to be integrated with both abiotic and biotic factors recorded at a microscale before reliably predicting nest temperatures. Among the nest types used by lesser kestrels, we detected a preferential occupation of the cooler nest types, roof tiles, by early breeders whereas, paradoxically, late breeders nesting with hotter temperatures occupied the overheated nest holes. Not consistent with such a suggested nest selection, the coolest nest type did not host a higher reproductive success than the overheated nests. We discussed our findings in the light of cavity temperatures and nest types deployed within conservation actions assessed by integrating selected factors at different observation scales
AACVD synthesis of catalytic gold nanoparticle-modified cerium(IV) oxide thin films
Co-deposition of Ce(dbm)4 and NH4AuCl4 precursors in acetone at 500 °C via AACVD results in deposition of crystalline CeO2 thin films containing/decorated with metallic gold. These particles are estimated to be ∼ 70 nm in size via optical methods. Preliminary testing of catalytic activity showed the materials were surprisingly catalytically active given the very small amounts of gold present and the large estimated particle size, although the presence of smaller catalytically active particles could not be discounted
Geomorphology of the urban area of Palermo (Italy)
The results of a geomorphological study carried out in the urban area of Palermo are summarized in a thematic map. Field survey, analysis of aerial photographs and topographic maps, consultation of historical documents and maps, stratigraphic and topographic reconstruction from numerous wells and subsoil data, and bibliographic search were performed, in order to display the geomorphological changes produced by man over time in a densely populated area and to define the Anthropocene of the study area. Palermo town rises along large marine terrace surfaces cut by small river valleys and bordered by wide degraded and abandoned coastal cliffs. Over the last 2700 years, this area was affected by remarkable man-made changes to topographic surface and underground, exposing large areas of the city to hydraulic, sinkhole, and landslide risks, and increasing the levels of seismic susceptibility. In light of these results, the produced map is useful for urban planning studies
INTEGRATED SURVEY AND SMART NAVIGATION OF COMPLEX TERRITORIAL MODELS
Abstract. The study examines the numerous medieval fortified sites that are in ruins throughout the Sicilian territory. Their landscape and historical value is significant, but they are unfortunately abandoned, not in stable conditions and often no metrically reliable graphic representation exists.The methodology we chose required a combined 3D survey campaign and data processing aimed at obtaining 2D and 3D drawings, as well as a virtual reality application to provide knowledge and virtual fruition of the sites.The entire experimental procedure was optimised to provide multi-scalar readings of the sites under investigation, that include their details, the location, territory, and landscape.The article presents the results of a case study carried out on the Maletto Castle in Sicily (Italy)
Distal ureteral stump: case report
Introdution. Distal Ureteral Stump is a residual ureter after total or partial nephrectomy. It is a rare complication and it also
appears many years after surgery. Majority of patients are asymptomatic but Literature reports patients with recurrent bacteriuria
or haematuria, empyema, stones and tumors (transitional-cell carcinoma or renal-cell carcinoma). We present one
case of diseased ureteral stump and surgical strategy.
Case Report. We report a case of a patient subjected to retroperitoneoscopic total nephrectomy when he was seven months
old for sympthomatic right vesico-ureteral reflux of IV grade and associated renal hypoplasia. These patient presented recurrent
urinary infections after 3 years from the surgery and for this reason we performed voiding micturating cystourethrography
who revealed the presence of urinary reflux in the DUS. Because of this surgical removal of stump was necessary and during
2 months follow-up was normal and there weren’t surgical complications or UTI.
Discussion. Distal Ureteral Stump is a rare complication but possible after nephrectomy and it is due to partial excision of
ureter in the distal portion. Recurrent urinary infections are a usefull signal to subspect the presence of DUS and they are due
to persistent reflux of urine and dysfunctional voiding (reservoir) resulting in stasis and infections.
Therefore in all patients subjected to total or partial nephrectomy with recurrent urinary infections also after years, the presence
of DUS should always be suspected and radiological investigation must be performed for accurate managemen
Anthropogenic sinkholes in the Marsala area (western Sicily) linked to underground quarries
Marsala territory (western Sicily) is characterized by the presence of a Lower Pleistocene (Calabrian) calcarenite
succession (Marsala Calcarenite Fm). It can be divided into three lithofacies that show the regressive evolution
of the depositional system: a) coarse to fine yellow bio- and lithoclastic calcarenites, b) sands, and c) gray sandy
clays. At least 80 m-thick, this succession gently dips (5-10) towards the south and the south-west. At some
locations the Marsala Calcarenite is covered by Middle and Upper Pleistocene marine terraced deposits.
Since the Roman period, due to the great abundance of calcarenite rocks, and to the facility of extraction, the
Marsala area has been characterized by a high number of quarries for the extraction of this building materials.
Many of them were excavated underground, at depth varying from a few meters to about 25 m, and are arranged
in one or two levels, following the galleries and pillars excavation technique. With time, the underground quarries
have been progressively abandoned for the decay of the physical and mechanical properties of the calcarenite
rock mass, the interaction with the groundwater, the high costs of extraction, and the dangers and difficulties
encountered in working underground.
Since the 1960’s the quarries have been affected by instability processes, visible through collapses and deformations
of vaults and pillars. These phenomena often propagate upward reaching the topographic surface and
forming sinkholes which affect and severely damage the built-up area.
In particular, two case studies of sinkholes related to different underground quarries will be analyzed in this paper.
The aim is to provide a description of the most significant processes and factors responsible of the instability
processes based on field surveys, as well as to understand the generation mechanisms of these anthropogenic
sinkholes by means of numerical modeling, based on rock laboratory testing data, that represents in these cases
a remarkable tool for the investigation of the cause-effect relationships, as already performed in other areas of Italy
HYPERPLASIA OF THYMIC GLAND: LEFT VIDEO-ASSISTED THORACOSCOPIC APPROACH
Hyperplasia of thymic gland is a rare benign entity that should be considered in the differential diagnosis of anterior
mediastinal masses in children and young adolescents. We report a case of a patient with a thymic mass, diagnosed occasionally
for respiratory symptoms and treated by video-assisted thoracoscopic surgery. A previously healthy 10 years-old boy
presented to our hospital for retrosternal pain and dyspnea with restriction to daily activities from four months. Diagnostic
imaging was performed, including a chest x-ray and a magnetic resonance imaging, showing a large homogeneous anterosuperior
mediastinal mass, more extended on the left side. The additional laboratory analysis, considered essential for differential
diagnosis with myasthenia gravis and lymphoma, resulted negative. In view of these findings, our patient underwent
to video assisted thoracoscopy with left-sided approach for a total resection of thymus and perithymic fat. The patient made
an excellent recovery without postoperative complications and was discharged from the hospital four days later. Histopathological
examination showed a normal thymic architecture like a true thymic hyperplasia. At follow up, chest x-ray was normal
in absence of pleural and parenchimal alterations. Thoracoscopic thymectomy is a safe technique that allows to achieve the
goal of early thymectomy with the advantages of less invasive procedure
Quaternary marine and continental unconformity-bounded stratigraphic units of the NW Sicily coastal belt
In the coastal sector of NW Sicily, the regional correlation of relevant unconformities recognised within the Quaternary sedimentary successions allowed the mapping of seven unconformitybounded stratigraphic units (UBSUs). The regional unconformities are marine or subaerial erosional surfaces, as well as non-depositional surfaces, locally marked by paleosoils. The erosional surfaces were produced from marine abrasion, surface water overland/ concentrated flow, river erosion, karst solution, mass movement, or wind erosion. The main lithofacies of the Quaternary UBSUs consist of: (a) marine and coastal bioclastic calcarenites, (b) aeolian sandstones, (c) river deposits, (d) colluvial deposits, (e) talus slope deposits, (f) landslide deposits, and (g) chemical carbonates (travertines and speleothems). Quaternary environmental changes, due to tectonics, climate, and sea-level oscillations, are the causes that favoured the development of erosion/deposition processes responsible for the genesis of unconformities and deposits. As a result, through the UBSU map of the NW Sicilian coastal belt, it is possible to: (i) recognise stratigraphic units controlled by tectonic, climatic, and environmental processes (and their interplay) and (ii) detect Quaternary sedimentary evolution
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