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Plio-pleistocene tectonic evolution of Southern Sardinia
Get PDFUp to now there are not detailed studies about the structures and the kinematic related to the Plio-Pleistocene tectonics in southern Sardinia, although tectonic activity during the latest million years is long since known in the Island. Then, the general aim of this research is to improve the understanding of the recent geological evolution of the southern Sardinian block, trying to calculate the extension affecting the crust, to reconstruct the paleostress fields and to define a model of the tectonic evolution of the southern Sardinia during this period, considering the new data obtained from this research and the data available from literature on the geodynamic evolution of the western Mediterranean, in particular about the opening of the Tyrrhenian Sea. To achieve this purposes, the research focuses on the study of the most important structure related to the Plio-Pleistocene tectonics: the "so-called" Campidano graben. This structure has been studied mainly interpreting the seismic lines acquired in the Campidano plain by SAIS in the early sixties and by the joint venture AGIP-Progemisa S.p.A. in the early nineties that have been made available for this research by the Regione Autonoma della Sardegna and Progemisa S.p.A. The continuation of the Campidano in the Cagliari Gulf has been studied interpreting the ministerial seismic lines aquired by AGIP in the seventies in the offshore of Cagliari.
The main results achieved from the research are:
- the 3D model of the Middle Pliocene erosional surface at the base of the Samassi formation detected in the subsurface of the Campidano plain;
- the extension values and the deformation rates affecting the Campidano area during Plio-Quaternary times;
- the reconstruction of the paleostress field active during Pliocene time in the Campidano graben;
- a comparison between the structural setting of the Campidano and the structural setting of the southeastern Sardinian margin;
- the integration of the data achieved during this research with the data available from literature on the geodynamic evolution of the western Mediterranean, in particular about the opening of the Tyrrhenian Sea.
The 3D model of the Middle Pliocene erosional surface has been built using the two-way time structural maps of this surface carried out in both the northern and southern Campidano. This surface shows a gently rolling landscape, typical of the erosion and planation surface developed in continental environments, both in the subsurface of the southern and northern Campidano plain. In the Campidano of Oristano, the maximum depth of the bottom of the Samassi formation is approximately -1100 m, while in the southern it is roughly -900 m (mean velocity assigned 2 km/s).
The two-way time structural maps show that both the northern and the southern Campidano graben are bounded in the western edges by master faults dipping to the east, but differences arise in the trends of the faults: mostly N-S in the northern Campidano and NW-SE in the southern Campidano.
N-S normal faults affected the whole Samassi formation and the within-plate basalts that post-date it, so we may admit that an important extension occurred after its deposition, that is in Pleistocene time.
The structures from seismic interpretation, that characterized the Plio-Quaternary evolution of the so-called Campidano graben have been validated during the drafting of the two-way time maps and with the structural and stratigraphic data available on surface. This allowed to construct a validated 3D model from which achieved the most possible reliable values of extension and paleostress.
To quantify the Plio-Quaternary deformation in southern Sardinia the 3D model of the Middle-Pliocene erosional surface (roughly 3.5 Ma in age) has been considered. The extension has been calculated restoring the cross-sections achieved from the 3D model. In the southern Campidano, extension values range from 205 m to 596 m and the percentage of extension from 1.65% to 5.72%. In the northern Campidano extension values range from 171 m to 465 m and percentage of extension from 0.84% to 2.50%.
Although the Plio-Pleistocene time-markers (3.5 Ma the erosional surface at the base of the Samassi formation and 2.5 Ma the surface sealed by the basalt lava flows in northern Campidano and a reflector calibrated with the Campidano1 well in the southern Campidano) are not very well constrained, they allow to estimate the vertical slip rate (0,6 mm/yr) and the extension rate (0,3 mm/yr in the northern Campidano and 0,4 mm/yr in the southern Campidano).
Considering the erosional surface sealed by the basalt-lava flows of the "giare" to the east of Campidano that occurs up to 550 m above the sea level and the age of 3.0 Ma of the basalts that seal it, an uplift rate of 0.18 mm/yr can be calculated if a marine origin for this surface is confirmed. Furthermore, the difference in elevation between the higher basalts that crop out in the central Sardinia (approximately 700 m in the Orroli basalt plateau) and those detected in the subsurface (-440 m in the northern Campidano) is related to tectonic activity that is at least Pleistocene in age. Therefore, during the whole Plio-Quaternary tectonics, considering the Middle Pliocene erosional surface at the base of the Samassi formation detected at -1100 m in the northern Campidano, vertical displacements on the order of 1800 m can be inferred.
The paleostress field active during Pliocene time in the Campidano area has been reconstructed using the movement vector on the fault plane achieved from the restoration of the Middle Pliocene erosional surface in both the northern and southern Campidano using two different methods that showed almost the same results.
In the northern Campidano, an extension oriented roughly E-W, with the principal stress axes: σ1=263/77; σ2=356/1; σ3=86/13; has be inferred. In the southern Campidano, the extension is oriented roughly ENE-WSW, with the principal stress axes: σ1=105/85; σ2=332/3; σ3=242/3.
The evolution during Pliocene in the southern Sardinia seems to be strictly related with the evolution of the sector of the southern Tyrrhenian basin located roughly south of the 40° parallel. This can be infer from the similarities in ages and stuctures in the eastern Sardinian margin and Campidano area. It seems that the extensional tectonics started in the Upper Miocene in the Sardinian Basin and Cornaglia Terrace and migrated westward in Sardinia and eastward in the Vavilov Basin.
Concerning the Pliocene tectonics affecting Sardinia, therefore, it seems to be directly related to the beginning of the extension in the Tyrrhenian Basin, due to the eastward roll back of the subducting Adriatic plate.
It seems, instead, that the Pleistocene tectonics recognized in Sardinia can not be related directly with the evolution in the Tyrrhenian Basin, because, although extensional tectonics continued in the Marsili Basin until now, no active tectonics occurs in the Sardinian Basin and Cornaglia Terrace. Thus, the recent uplift affecting the southern Sardinia is most likely related to the lithospheric structure inherited from the pre-Pliocene geodynamic evolution of the western Mediterranean, during which the lowering of the density in the mantle lithosphere could be caused an uplift up to 1620 m, if a normal thick mantle lithosphere (90 km) is considering as start point, or up to 720 m, considering the present day thinned mantle lithosphere (40 km), or by the thinning of the mantle lithosphere connected with process of intensive convective heating (thermal thinning)
Nanocarriers for drug targeting and improved bioavailability
Get PDFThis PhD thesis debates, mostly, on two main topics:
- Drug delivery to brain
- Nanosuspensions for different applications
The objective of the first topic was the development of liposomes to which anti-TfR-monoclonal antibodies (Ox26) or lactoferrin was bounded to transport the selective NK3 receptor agonist senktide to CNS across the BBB. NK3 receptors are widely expressed in the CNS and their stimulation by senktide (ICV) increase extracellular DA. Liposomes were prepared using the film hydration method. In vivo microdialysis studies were performed to estimate the responsiveness of NAc shell DA to senktide as a consequence of its CNS delivery. Senktide given ICV or loaded into Ox26/lactoferrin-liposome (0.5 μg/kg iv) elicited a significant increase of dialysate DA in the NAc shell of rats whilst senktide given iv (0.1 mg/kg) or loaded in control stealth liposomes did not affect NAc shell DA. Liposomes formulation here described represent an effective way of CNS delivering of senktide following intravenous administration the TfR-transport system. On the other hand, three different types of nanosuspensions were formulated and studied:
- Tretinoin nanosuspensions for topical delivery
- Piroxicam nanosuspensions loaded in oral disintegrating tablet (ODT) for oral delivery
- Quercetin nanosuspensions loaded in fast dissolving films for oral delivery
The aims of the first work were to improve cutaneous targeting and photostability of tretinoin by using nanosuspension formulation. Tretinoin is a drug widely used in the topical treatment of various dermatological diseases. The tretinoin nanosuspension was prepared by precipitation
method and then characterized by photo correlation spectroscopy for mean size and size distribution, and by transmission electron microscopy for morphological studies. An oil in water tretinoin nanoemulsion was also prepared and used as a control. Dermal and transdermal delivery of both tretinoin nanosuspension and nanoemulsion were tested in vitro by using Franz diffusion cells and newborn pig skin. Photodegradation studies were carried out by UV irradiation (1 h, λ=366 nm) of the tretinoin nanosuspension in comparison with the nanoemulsion and a methanolic solution of the drug. During 8 h percutaneous experiments, no permeation of tretinoin through the whole skin thickness was detected but the drug was deposited into the skin layers, mainly in the stratum corneum, similarly to the nanoemulsion. UV irradiation of the nanosuspension showed a great improvement of tretinoin stability in comparison with both controls. Overall results show that nanosuspension might be a useful formulation for improving tretinoin dermal delivery and stability. Piroxicam (PRX) is a non-steroidal anti-inflammatory drug characterized by a poorly water solubility and consequently by a low oral bioavailability. Different nanocrystals orally disintegrating tablets (ODT) were prepared to enhance piroxicam dissolution velocity and saturation solubility. Nanosuspensions were prepared using high pressure homogenization technique. Different ODT formulations were prepared using the same nanosuspension but changing different excipients in order to optimize dissolution properties. PRX nanocrystals size and zeta potential were determined by photon correlation spectroscopy (PCS). Characterization of PRX nanocrystals ODT was carried out by infrared spectroscopy (FTIR), X-ray powder diffractometry (XRPD), differential scanning calorimetry. Dissolution study of PRX ODT was performed in distilled water (pH 5.5) and was compared with PRX coarse suspension ODT, PRX/poloxamer 188 physical mixture, bulk PRX samples and a piroxicam commercial ODT (Feldene). All PRX nanocrystals ODT formulations showed a higher drug dissolution rate than coarse PRX ODT. PRX nanocrystals ODT prepared using gelatin or croscaramellose as excipient showed a higher PRX dissolution rate compared with the commercial formulation and with ODT prepared using xanthan gum. The improvement in PRX dissolution rate is mainly caused by the increased surface-to-volume ratio due to the submicron
dimension of the drug nanocrystal, however, also the presence of the correct excipients (as disgregant) seem to play an essential role. Finally, quercetin nanosuspensions loaded fast dissolving films were formulated and studied. The aim of this work was to investigate the possible use of maltodextrin IT6 (MDX) to prepare fast-dissolving films, loaded by quercetin nanocrystals. Quercetin nanosuspensions were prepared using an high pressure homogenizer, meanwhile drug loaded films were obtained drying in a siliconized polyester sheet quercetin nanosuspensions with the others compounds in a oven at 60 °C. Films were finally cut and packed within sealed aluminium pouches. Quercetin nanocrystals were characterized by photo correlation spectroscopy for mean size and size distribution and by transmission electron microscopy for morphological studies. On the other hand, quercetin nanosuspensions loaded films were characterized in term of flexibility, tensile strength and thickness. Finally, dissolution studies in distilled water were performed, comparing release profiles of quercetin loaded films, quercetin raw material and quercetin nanosuspensions
Studio delle forme chimiche e mineralogiche e della mobilità/biodisponibilità di metalli pesanti in suoli, piante (Pistacia lentiscus L.) e soluzioni del suolo del Bacino del Rio San Giorgio (Iglesias – Gonnesa, Sardegna sud - occidentale, Italia) finalizzato allo sviluppo di strategie di soil remediation
Get PDFThis study was addressed to the environmental consequences that the intense extractive activity of
lead and zinc has produced in the district around the towns of Iglesias and Gonnesa (southwestern
Sardinia, Italy), with particular reference to the soil and to possible actions of phytoremediation.
The research project, performed in cooperation with various national and international institutions,
including ENEA, CNR and NTU (Nottingham Trent University), focuses the investigation on
different aspects related to environmental pollution by elements such as Zn, Pb and Hg associated
with the mines of the district.
The study is located in the area of the Rio San Giorgio basin, where the following representative
sites were chosen: one of the ‘hazard centers’ of the district, consisting of mining flotation wastes at
Campo Pisano, close to the town of Iglesias; three natural sites, not directly affected by
morphological alterations due to mineral extraction, located along the ‘metalliferous ring’, that is
the Cambrian limestones-dolomites that host the Pb-Zn mineralisation; the Sa Masa swamp, that is
the final collector of drainage waters of the river basin, closed by the Iglesias valley to the north and
the Sulcis coal district to the south.
The aims of this work are: i) to quantify the total content of ‘heavy metals’ in the various abiotic
sectors (soils and soil pore waters), and in the biotic sector, specifically Pistacia lentiscus L., a
spontaneous vegetal species; ii) to identify the chemical and mineralogical forms of heavy metals,
and to define their mobility and bioavailability in the interactive environmental system soil - plant -
soil pore water; iii) to study the relationship between the different concentrations of heavy metals in
the various environmental media considered, to understand the mobility mechanisms; iv) to
establish how much Pistacia lentiscus L. takes up and translocates each metal from roots to leaves,
through the relationship of the contents measured in each plant parts, hypogeans and epigeans; v) to
provide a full description in situ of the spontaneous system of vegetal species selected, that
characterizes these contaminated zones, as an example of phytostabilization and soil remediation techniques, aimed to reclamation and stabilization of the abandoned mining areas.
In the sampling points, soil profiles were opened, making a distinction in pedological horizons according the standard procedures of soil investigations; samples were collected for each horizon for subsequent laboratory analysis. These included the determination of chemical and physical characteristics according to the official Italian soil study methods. In general, the soils studied in the mining wastes are not pedogenised; those on dolomitic limestones are sparsely and moderately deep, in lithic contact with the underlying rock; the soils in the marshy deposits are characterized by a sequence of different sedimentary cycles (marked by textural differences). The pH reaction is generally from neutral to weakly alkaline (from 7.1 to 8.1), with variations and exceptions attributable to different parent materials from which the studied soils originate. The mineralogical and chemical analyses point out a great abundance of calcite and dolomite, in agreement with the geological substrate of the area. The organic carbon contents are generally higher in the surface horizons, with minimum value of 11 g/Kg and maximum of 202 g/Kg, and they decrease at increasing depths. The study of thin sections allowed to refine the attribution of acronyms to the horizons, according to the international soil classification systems of the Soil Taxonomy and IUSS Working Group.
On the same soil samples were carried out further mineralogical determinations (X-ray powder diffraction), loss on ignition (LOI), and chemical composition (major elements with X fluorescence; trace metals with acid digestion followed by analysis with ICP-OES). In agreement with thin sections, calcite and dolomite result abundant, as well as quartz; in some samples the presence of barite, pyrite and gypsum was detected, as well as trace 'heavy metals' minerals (hemimorphite, cerussite, hydrozincite, anglesite). Consistent with mineralogy, the chemical composition is dominated by CaO-MgO-SiO2.
Among the analysed heavy metals, Zn, Pb, As, Cd, and Hg very often occur in higher concentrations than Italian law limits (D.Lgs 152/2006) for the metal contents in soils for industrial use; particularly high are the contents of Zn (1655-220946 mg/Kg), and Pb (1360-54914 mg/Kg). These values are found also in the soils developed on natural substrates, presumably not much interested by anthropic impacts, reflecting therefore a natural geochemical anomaly; however, in the sites impacted by the mining activity all values are higher, demonstrating the influence of anthropic action.
The mobility of metals was estimated through two different single extraction chemical methods: with DTPA solution, followed by analysis of the extracted metals by ICP-OES, and with sodium citrate/hydroxylamine hydrochloride/TEA followed by colorimetric titration with Dithizone (DZ)
solution. The data comparison showed a good correlation between these two methods (R2=0.93), with values obtained from the DZ method roughly double with respect to those from the DTPA method. The mobile fraction extracted with both methods reveals a good correlation also with the total metal contents in soils (R2=0.98 for DZ; R2=0.92 for DTPA).
As mentioned previously, a particularly innovative aspect of this study was the sampling and analysis of soil pore waters. Their chemical composition is variable among the various sites, and one can identify at least two principal compositional types (Ca-SO4, Ca-Mg-HCO3): to this last type, a Na-Cl-SO4 component of possible seawater origin is locally associated. Regarding the trace elements, the metals more abundant are Ba in some sites, and Zn in others; this last is usually the more abundant trace metal, particularly if compared to Pb. The modelisation with the speciation programs PHREEQC and WHAM shows in general an approach to equilibrium of the solutions with the minerals present in soils; specifically, the concentrations of Ba, Zn and Pb appear substantially controlled by barite, hydrozincite and cerussite, respectively. As concerns the transfer of metals to the biosphere, it was carried out also the sampling of P.lentiscus, on which the contents of Zn, Pb and Hg were determined, for roots, stems and leaves separately. In general, the metal concentrations decrease according to the order roots>stems>leaves, with the partial exception of Hg, for which there is locally an enrichment in leaves (TF>1), perhaps influenced from foliar absorption of Hg volatilised from soils. The metal contents in plants are considerably lower than those in soils (BAC<<1), and nevertheless roughly proportional to them. The P.lentiscus seems in fact to behave as a tolerant species with strategies of exclusion, and with character of 'indicator'. It is confirmed therefore that this species is particularly apt to revegetation actions aimed at the phytostabilisation of soils
Ultrafast Optical Spectroscopy Techniques applied to colloidal nanocrystals
Get PDFIn this thesis I will describe my experimental work based on ultrafast optical spectroscopy techniques applied to colloidal nanocrystals.
Colloidal semiconductor nanocrystals in recent years have attracted a lot of attention in particular in optoelectronic applications, because they present
unique optical, electronic and charge carrier transport properties that can be easily modified via colloidal chemical synthesis.
In the first chapter of this thesis, I will introduce the basic concepts of nanocrystals and their optical properties, I will consider some simple models
to explain the physical properties of semiconductor nanocrystals. I will briefly describe the colloidal chemical synthesis of these nanocrystals and how we
can change the optical properties by simply acting on the colloidal chemical synthesis.
In the second chapter I will describe the basic concepts of ultra fast optical spectroscopy techniques used in my experimental work. I will describe the basic principles and the experimental set-up of the two main techniques that I
used: time-resolved photoluminescence spectroscopy (TR-PL) and transient absorption spectroscopy or also called Pump Probe. These two techniques allow to investigate in a very precise way the main optical properties and dynamics of charge carriers in nanocrystals.
In the third chapter I will describe my experimental work based on timeresolved photoluminescence spectroscopy applied to CdSe=CdS core=shell nanocrystals. These nanocrystals are a reference nanocrystals and their optical
properties are extensively investigated, however, some aspects are not fully understood, for example, the instability or blinking of the light emission
under constant illumination in these nanocrystals is still an unsolved problem that limits the real applications. The particular spectroscopic technique that I have used variable pulse rate photoluminescence spectroscopy revealed
the causes of this issue, and will give us a solution to resolve it.
In the fourth chapter I will discuss novel nanostructures of CdSe=CdS multi branched shape, in this case octapod shaped nanocrystals consist of eight arms made of CdS grown on a CdSe core, these present a large crosssection for light absorption and efficient charge separation ideally suited for applications of photocatalysis. The optical spectroscopy technique used to investigate the properties of these nanocrystals are the transient absorption
spectroscopy.
In the fifth chapter I will discuss experimental work on Bi2S3 semiconductor nanocrystals and I will describe related optical techniques used to study the optical and electronic properties. This nanocrystal has excellent
properties of optical absorption of solar radiation and can be used for the realization of solar cells. Another important property of Bi2S3 is its nontoxicity
that will allow in the future to achieve efficient solar cells and easy disposal and simultaneously not damaging to the environment
Possibili differenze sesso-specifiche nella vulnerabilità alle sostanze d’abuso in età adulta dopo esposizione al Δ9-tetraidrocannabinolo durante l’adolescenza
Get PDFIt is well established that early cannabis use during adolescence leads to neurobiological changes that can affect adult brain functions which in turn might lead to an increased vulnerability to drug abuse (Realini et al., 2009). Epidemiological evidence of cannabis use before other drugs has reinforced the idea of the "Cannabis gateway hypothesis" according to which early exposure to cannabis increases the risk of starting the use of harder drugs, such as heroin, cocaine and amphetamine (Kandel, 1975). Indeed, several studies have suggested the presence of significant functional interactions between the endocannabinoid and dopamine systems (Cheer et al., 2007; González et al., 2002) in the mesolimbic pathways, but also between endocannabinoid and opioid systems (Fattore et al., 2005) and between endocannabinoid and the cholinergic-nicotinic systems (Scherma et al., 2008) necessary for the expression of heroin and nicotine reward-related behaviours. Moreover, sex-dependent differences are frequently observed in the biological and behavioral effects of drugs of abuse (Becker and Hu, 2008) and in keeping with epidemiological data in humans, differences in drug-intake and seeking have been well-documented in animal studies, and the most recent findings have implicated cannabinoid abuse as well. (Fattore et al., 2010). Clinical and preclinical findings indicate that sex and gonadal hormones may account for individual differences in susceptibility to the reinforcing effects of addictive substances, and that differences in vulnerability to drug abuse may be mediated by the same biological mechanisms (Fattore et al., 2009). The aim of this study was to evaluate whether exposure to THC, primary psychoactive substituent of cannabis, during adolescence is able to increase the reinforcing effects of drugs of abuse such as nicotine, heroin and cannabinoids in adult male and female rats, and to compare the results obtained in order to identify possible sex-specific differences. To this end, behavioral studies have been conducted on both male and female rats using a validated experimental model to study dependence (O’Brien et al., 2005): the chronic intravenous self-administration (IVSA). Male, at 45 postnatal day (PND) and female adolescent, at 35 PND, Sprague-Dawley (for nicotine and heroin studies) and Lister Hooded rats (for WIN55,212-2 studies) (Deiana et al., 2007), were treated intraperitoneally (i.p) with increasing doses of THC (2.5, 5 and 10 mg/kg) or with vehicle twice/day for 11 consecutive days. Once animals reached the adulthood (85 or 75 PND), we studied the effects of THC exposure on acquisition and maintenance of nicotine (30 μg/kg/infusion), heroin (30 μg/kg/infusion) and cannabinoid agonist WIN55,212-2 (12.5 μg/kg/infusion) IVSA using continuous fixed-ratio (FR-1) schedule of reinforcement with lever-pressing as operandum. Faster acquisition and higher rate of drug intake was considered as index of vulnerability to drug abuse. Behavioral data obtained with male rats showed that exposure to THC during adolescence produces an increased vulnerability to CB1 receptor agonist WIN55,212-2 and heroin but not to nicotine intake in adulthood with respect to each control group. Data from nicotine self-administration in adult female rats showed no differences in intake between animal exposed to THC in adolescence and vehicle-treated rats. On the other hand, THC adolescence exposure increased both heroin and WIN55,212-2 intake as compared to corresponding control groups. Comparison of results obtained in females and male rats of heroin and WIN55,212-2 IVSA experiments shows that average intake of drugs during the maintenance phase of self-administration training is significantly higher in females than in males. This increased vulnerability of female rats to drug taking as compared to males is in line with previous studies on sex-dependent differences showing that females are more sensitive than males to cannabinoid-induced behavioral effects. In summary, these studies seem to support the hypothesis that a previous exposure to THC during adolescence increases the vulnerability to heroin and cannabinoids, but not to nicotine abuse in adult rats with sex-specific differences
Effetto dell’etanolo sullo stato di metilazione del gene che codifica per la neurotrofina “Brain-Derived Neurotrophic Factor”
Get PDFAlcohol addiction is thought to depend on molecular and cellular adaptations in the brain that result from chronic drug exposure (Fitzgerald and Nestler, 1995 ). This suggests that chronic alcohol abuse involves stable changes in the brain at the molecular and cellular levels responsible for long-lasting alterations in behavior. One of the candidate molecules involved in such mechanisms is brain-derived neurotrophic factor (BDNF). Aberrant regulation of BDNF has been implicated in the development of psychiatric disorders, including schizophrenia, depression, anxiety and alcohol addiction (Moonat et al., 2010). Multiple actions of ethanol on BDNF gene expression and signalling have been described. Nevertheless the considerable complexity within the BDNF gene itself and the multiple mRNAs encoded by up to 9 potential exons is further complicated because of its epigenetic regulation by methylation of BDNF promoters. The knowledge of the promoter that may be differentially regulated during various states of ethanol exposure and a detailed analysis of the effects of different ethanol exposure treatments on mRNA expression is required to understand the biological basis of addiction. This will lead to more effective treatments and eventually to cures and preventive measures to treat alcohol addiction. The aim of this work was to evaluate the effects of ethanol on CpG islands of BDNF exon IX gene in regulating its expression, both “in vivo” and “in vitro”. Rat cerebellar granule cells in culture were exposed to acute ethanol, chronic ethanol or ethanol withdrawal. Our results demonstrate that ethanol exposure increases, the abundance of BDNF exon IX transcript in the three different treatment conditions. We then tested the ability of acute ethanol to alter exon IX methylation by using MSP PCR. Similarly to the effect induced by the two DNA methylation inhibitors, zebularine and RG-108, exposure of cultured neurons to 100 mM ethanol for 3h significantly increased the unmethylated state of BDNF exon IX that was about 2.5 folds grater than the methylated state. This epigenetic action of ethanol was observed also in the hippocampus of male rats treated with increasing doses of ethanol (0.8; 1.6 or 3.0 g/kg; i.p.) tested 1; 3 and 5h after injection. Ethanol induced a significant time and dose dependent increase in BDNF exon IX unmethylated DNA levels, compared with control, which showed a positive correlation with BEC. The increased unmethylated state was accompanied by a corresponding increase in the abundance of BDNF exon IX transcript. The increase in mRNA was dose
dependent with the maximal effect at 3.0 g/kg 3h after injection. These results provide the first evidence for an alternative way of ethanol to alter BDNF gene expression. Thus, ethanol induced changes in CpG DNA methylation of BDNF gene seems to be an additional mechanism to implement homeostatic protective actions to prevent adverse effects of ethanol. The ability of ethanol to induce up regulation of BDNF may play a pivotal role and could result from a number of intracellular responses that include the epigenetic mechanism here described.
Fitzgerald and Nestler, (1995). Clinical Neuroscience 3(3):165-73.
Moonat et al., (2010). Cellular and Molecular Life Sciences 67(1):73-88
Phthiraptera Anoplura della Sardegna: analisi delle coinfestazioni ectoparassitiche rilevate su animali d'allevamento e selvatici
Get PDFThe studies on arthropods of medical and veterinary importance carried out in
Sardinia until now not yet provide a clear and comprehensive overview on the taxa
present, their distribution, phenology and the pathogen role. Phthiraptera Anoplura (=
Siphunculata), which includes the so called "sucking lice" was almost never
investigated in Sardinia. They are small insects, obligatory permanent ectoparasites,
characterized by a high host specificity and a high ethological, physiological and
anatomical specialization, including the wingless. They feed on epidermal tissues, and
the entire life cycle of the Anoplura takes place on the host. Heavy louse infestation
may cause to their hosts pruritus, alopecia, weakness, irritability, weight loss and
anaemia. They are also potential vectors of pathogens that can cause severe disease in
domestic and wild animals as well as humans. One of the most famous can be
considered the epidemic typhus whose etiologic agent is Rickettsia prowazeki. It is to be
noted that the Anoplura have been little studied all around Italy and the few available
published papers are occasional, sporadic and, apart from some recent works, already
old.
The aim of this PhD was to shed light on Phthiraptera Anoplura in Sardinia,
taking into consideration the list of species present on the island, their distribution,
phenology, and which mammals are parasitized. In this paper the Anoplura and other
arthropod ectoparasites were collected on living and dead animals.
The search for parasites was performed by examining the fur and skin of
animals, concentrating on the areas of the body more vascularized and susceptible to
localization of blood-sucking arthropods. So depending on the host species, was mainly look for the ectoparasites the regions of head, ears, neck, abdomen, the inguinal region
and the perianal area. All arthropods found were fixed in 70% ethanol and later
identified morphologically at the microscope.
The collection of specimens in Sardinia provide information about twelve
species of Phthiraptera Anoplura belonging to 6 families: Pediculidae (1 species),
Phthiridae (1 species), Haematopinidae (4 species), Linognathidae (4 species),
Hoplopleuridae (1 species), Echinophthiriidae (1 species). Were found 121 samples of
arthropods with a total of 1294 specimens: 37 Pediculus capitis and 19 Phthirus pubis
on man; 144 Haematopinus apri on wild boar; 1 Haematopinus asini on horse; 97
Haematopinus suis on pig and wild boar; 18 Haematopinus tuberculatus on buffalo;
787 Linognathus africanus on goat and sheep; 73 Linognathus stenopsis on goat and
mouflon; 2 Linognathus vituli on cattle; 116 Solenopotes burmeisteri on Sardinian red
deer. To add at the list, in literature two other species were cited for the island:
Schizophthirus pleurophaeus found on the Eliomys quercinus sardus and
Echinophthirius horridus found on Monachus monachus. Among other parasites (349
specimens) detected in coinfestation with Anoplura were identified 171 Acari Ixodida
Amblyommidae: 73 Rhipicephalus bursa on goat, cattle, horse, sardinian red deer and
mouflon; 50 Rhipicephalus turanicus on goat, sheep, pig, wild boar and mouflon; 8
Haemaphysalis punctata on goat and mouflon; 4 Haemaphysalis sulcata on mouflon;
31 Dermacentor marginatus on wild boar and mouflon; 5 Hyalomma marginatum on
cattle and horse. On goat also were captured 7 fleas (Siphonaptera) belonging to
Ctenocephalides felis (1 specimen); Ctenocephalides canis (1 specimen); Pulex irritans
(5 specimens). On a horse was captured a specimen of Hippobosca equina (Diptera
Ippoboscide). Were also found 170 Phthiraptera Ischnocera Bovicolidae: Bovicola caprae (143 specimens on goat); Bovicola ovis (23 specimens on sheep and mouflon);
Bovicola equi (4 specimens on horse). These three species are at first founded in
Sardinia. It has been reported the coinfestations between Anoplura and other parasites
taxa in about the 80% of cases, on all the host species, except for man and buffalo. Here
there are first reports for Sardinia for at least eight Phthiraptera species; among them
Linognathus africanus was just recently reported on the Italian continental part, in
Emilia Romagna, and is known in Europe only of Spain, Greece and Turkey.
Haematopinus tuberculatus was also only recently reported of central-southern Italy.
Solenopotes burmeisteri, was never previously officially reported for Italy but
presumed. Besides the new species checklist a preliminary distribution maps for each
species of Anoplura are provide.
This study collect important new information about the species of ectoparasites
that infest mammals in Sardinia, increasing meanwhile the knowledge about the same
also in Italy and in the Mediterranean Basin. The results obtained also provide a starting
point for faunistic, parasitological and epidemiological future works, for the protection
and preservation of the regional livestock, wild animals and public health
The use of Sardinian granite by-products from the Sarrabus Gerrei region to be used in road pavement layers
Get PDFIn Sardinia abandoned granite by-products stockpiles deriving from different excavation and processing methods are becoming an environmental and economic concern. Currently, these materials derive mainly from the ornamental quarry industry, very active in the
region since late 1900’s, but also from civil engineering works consisting of tunnels, dams and other excavation projects. The storage of granite by-products in such great amount and for long periods produces damage to the environment, in terms of alterations of the
landscape that can be temporary but in several cases permanent wen waste deposits become part of the landscape surrounding, subtracting large extensions of land to more
important purposes such as agriculture. Also there is the visual and air pollution problem due to the suspension of fine particles in the air that these materials can produce when exposed for years to environmental climate conditions.
The possibility of using of such materials that are already been extracted and that for them energy and therefore CO2 emissions has already been spent, would decrease the use of
other natural aggregates that have yet to be excavated instead. Reducing the exploitation of non-renewable natural resources and limiting consumption of energy and CO2 emissions. In order to limit and in some cases solve some of these problems this thesis takes in to account the possibility of using granite by-products for road construction purposes. The possibility of using these materials, that in many cases are considered a waste, as a valid alternative to other aggregates that normally are used in pavement layers could decrease
road construction costs. In this research granite by-products from the Sarrabus-Gerrei region were studied to
evaluate the physical and mechanical properties to assess the possibility of using them to their fullest extent in both unbound and bound pavement layers. Three types of granite byproducts deriving from the same mother rock but subjected to different processes were studied. Two resulting from: Drill and Blast (D&B) and Tunnel Boring machine (TBM) excavation methods. The third material was obtained from the crushing of the larger blocks
obtained during D&B excavation. The work reported herein describes test conducted in order to determine the best suitable application according to the type of layer in which use such material, evaluating the possible variations in terms of physical and mechanical characteristics that granite by-product performed when subjected to different processes. A preliminary characterization was conducted evaluating the environmental compatibility
of such materials, based on Italian regulations on the use of excavated earth and rocks. The results of such tests were important to assess and determine the possible application in road pavement layers. Firstly, unbound layers were studied, analyzing aggregate properties and
performing tests on different mixes. Particular attention was given on the bound layers were both hydraulic and bitumen binders were studied. Soil-cement mixes were prepared using different percentages of Portland cement performing different. Then Hot Mix Asphalt
(HMA) samples were analysed in order to evaluate the affinity between granite and bitumen. Difficulties were emerged using this type of aggregates in HMA layers due to
adhesion problems between granite and bitumen. Stripping tests were performed and also attention was focused on the adhesion phenomena. In order to better understand such
phenomena and evaluate and measure potential parameters, digital image processing was conducted. Good values for the unbound layer, in which granite by-products were tested,
were measured. Furthermore, the use of such materials for cemented treated layers was evaluated obtaining as well good results
Sensitivity to chemical stimuli plays a fundamental role in the food preferences. Examples in the evolutionary scale: 1. Role of the walking leg chemoreceptors in the red swamp crayfish Procambarus Clarkii 2. PROP bitter taste sensitivity and its nutritional implications in Humans
Get PDFIn this thesis, we studied two examples of the sensitivity to chemical stimuli and its role in the food preferences in two models of the evolutionary scale.
The red swamp crayfish Procambarus clarkii (Girard, 1852) (Crustacea: Decapoda) is an invasive species of freshwater habitats that has spread worldwide. In crayfish, like in other decapod crustaceans, reception of chemical cues occurs by way of peripheral chemoreceptors grouped within sensory hairs and typically located on the cuticle of cephalothoracic appendages. Antennules and pereopods (walking legs), in particular, have been reported to be olfactory organs involved in a number of behavioral responses, such as, sex recognition and localization of food sources in the environment. By way of extracellular nerve recordings coupled with behavioral bioassays, we investigated the sensitivity spectra of the walking leg chemoreceptors in the crayfish P. clarkii in response to different compounds of feeding significance and related to its omnivorous habits. Our results confirmed a marked sensitivity of the legs to trehalose, cellobiose, sucrose, maltose, glycine and leucine. Some sensitivity to glucose, fructose, asparagine (all food indicators) and taurocholic acid was also found, the sugar-sensitive chemoreceptor units resulting as broadly tuned to the carbohydrates. Responses were highly phasic to trehalose (hemolymph sugar in the body fluid of many invertebrates), phasic to glycine and leucine and phasic-tonic to the other compounds. This suggests that chemoreceptor phasicity is an additional property for better discrimination of the protein components in the diet from other stimuli. The behavioral bioassays excluded, at least under confined experimental conditions, any involvement of antennules in the detection of food-related compounds, thus emphasizing the role of the crayfish legs as the main short-distance, broad-spectrum sensors for feeding. Such information may be valuable for the identification of key chemicals aimed at the future development of strategies for crayfish population control programs.
Taste sensitivity varies greatly in humans, influencing eating behavior and therefore may play a role in body composition. PROP bitter taste sensitivity is the most studied example of the individual variability of taste sensitivity. Some studies show that PROP bitter taste sensitivity may be correlated with sensitivity to other oral stimuli, food preferences and BMI, while other studies did not confirm this association. It is known that PROP phenotype is associated with variant in bitter taste receptors TAS2R38 and with density of fungiform papillae on tongue surface. Although most of PROP phenotypic variations are explained by the allelic diversity of the bitter receptor TAS2R38, they cannot explain the PROP taster status-related differences above all that in the perception to different oral stimuli. The aim of this study was identify and characterize other factors that may contribute to differences in the genetic predisposition to taste PROP and identify confounding variables which may explain the controversial data in the literature about the relationship between PROP taste sensitivity and BMI. 1) We investigated the possible relationship between PROP bitter taste responsiveness and salivary proteins by using HPLC-ESI-MS on saliva sample before and after PROP taste stimulation. 2) We evaluated the role of proteins and free amino acids in modulating bitter taste responsiveness. Subjects rated PROP bitterness after supplementation of two salivary proteins (Ps-1 and II-2), and the free form of constituent amino acids of the two proteins sequences (L-Arg and L-Lys) whose interaction with PROP was demonstrated by 1H-NMR spectroscopy. 3) We investigate the role of polymorphism rs2274333 (A/G) in the gene that codify for the salivary trofic factor gustin protein, in PROP sensitivity and fungiform papilla density and morphology and in vitro we investigate the effect of this gustin gene polymorphism on cell proliferation and metabolic activity, following treatment with saliva of individuals with and without the gustin gene mutation, and with isolated protein, in the two iso-forms. 4) We investigated whether the endocannabinoid system, which modulates hunger/satiety and energy balance, plays a role in modulating eating behaviour influenced by a sensitivity to PROP which could explain the controversial data in literature. In particular we determined the plasma profile of the endocannabinoids 2-arachidonoylglycerol (2-AG), anandamide (AEA) and congeners in normal-weight PROP super-tasters and non-tasters, also we assessed the cognitive eating behavior disorder by the Three-Factor Eating Questionnaire.
The results showed that: 1) Basal levels of II-2 and Ps-1 proteins, belonging to the basic proline-rich protein (bPRPs) family, were significantly higher in PROP super-taster than in non-taster unstimulated saliva, and PROP stimulation elicited a rapid increase in the levels of these same proteins only in PROP super-taster saliva. 2) Supplementation of Ps-1 protein in individuals lacking it in saliva enhanced their PROP bitter responsiveness. 1H-NMR results showed that the interaction between PROP and L-Arg is stonger than that involving L-Lys, and taste experiments confirmed that oral supplementation with L-Arg increase more PROP bitterness intensity than L-Lys. 3) Gustin and TAS2R38 genotypes were associated with PROP threshold, while bitterness intensity was mostly determined by TAS2R38 genotypes. Fungiform papillae densities were associated with both genotypes (with a stronger effect for gustin), but papilla morphology was a function of gustin alone. In vitro experiment, the treatment of isolated cells with saliva from individuals with AA form, and direct application of the active iso-form of gustin protein, increased cell proliferation and metabolic activity. 4) The disinhibition score of non-taster was higher than those of super-tasters. In addition, we found that the concentration
of endocannabinoid AEA (anandamide) and 2-AG (2-arachidonoylglycerol) was lower in the plasma of non taster compared with super-tasters subjects.
In conclusion, among the factors contributing to individual differences of PROP sensitivity, in addition to the TAS2R38 variants with its different affinity for the stimulus, we found: 1-2) the specific salivary proteins of bPRP family (Ps-1) and L-Arg that could be involved in twist and turn of the PROP molecule, thus facilitating its binding with the receptor. 3) A gustin gene polymorphism that, by modulating the protein activity, controls the growth and maintenance of taste buds and 4) the higher disinhibition behaviour in non-tasters may be compensated in part, in normal-weight subjects, by the decrease of peripheral endocannabinoids to downregulate the hunger-energy intake circuitry
Communication technologies and data processing for safety
Get PDFEmergency workers comprise large professional groups like volunteer fire-fighters, police officers,
emergency medical staff and so on. Their professions have to deal frequently with a considerable
number of a combination of health and safety risk factors, which are often unavoidable.
For example, workplace scenes demanding the intervention of emergency workers may be located
in remote, difficult to access areas (mountains, sea, caves), and sometimes in extremely difficult
weather conditions. Moreover, emergency workers must arrive very rapidly at the disaster scene at
any time of the day or night, and there is always the possibility of car crashes or other transportation
accidents on the journey to the disaster scene or to hospitals. Others examples are the industrial
workplaces, which are inherently places with a high concentration of heavy machinery, fast
handling equipments, high heat and pressure pipes, polluted and explosive areas where people work
in a relatively small area.
Therefore, in an environment where situational awareness and tactical decision making are critical
elements to a successful operation, it is really important to have available efficient instruments to
ensure the safety for all operators that work in the field.
Despite the fact that a lot sophisticated solutions have been used for increasing request due to the
growing need of safety concerns by the operators, the mission-critical environments are still
considered high-risk environments with serious work safety related issues and higher accident rates
than in other workplaces.
This study focuses on the safety precautions in outdoor and indoor environments, safety
communication and Personal Protective Equipment (PPE) and proposes solutions to ensure secure
and reliable communications between forces deployed in the field and their dispatch center, which
is often of decisive importance for the work of the emergency services, analyzing two different
important case studies.
Moreover, we have designed a control system intended as a platform for real-time information
capable of monitoring, by means of camera and sensor data harvesting about people and vehicles
movements. It provides automatic and semi-automatic risk prevention measures thanks to the work
in progress on designing and implementing a first working prototype of sensor network based on
RFID BAN. These capabilities are the topic of a larger research project that aims to find the optimal
solution in terms of feasibility and practical implementation.
To conclude our study, we have developed a indoor navigation system for mobile devices. The
application is able to follow the user and it indicates the shortest path to achieve a specific
destination. It uses only smartphone motion sensor and not requires the use of extra equipment.
Moreover, thanks to an algorithm widely explained afterwards and the use of the gyroscope sensor
rather than the compass, the mobile application ensure a very good orientation.
The thesis is organized as following:
- In the first chapter, to design a radio communication system both for health emergency
services and Civil Protection services, different Professional Mobile Radio (PMR) standards
was analized. PMR, also known as land mobile radio (LMR) in North America, are field radio
communications systems which use portable, mobile, base station, and dispatch console
radios. It has referred to a suite of radio mobile network tecnologies deployed for missioncritical
users, which need high affordable communication system. In the specific, PMR
networks provide radio services for closed user group, group call and push-to-talk, and call
set-up times which are generally short compared with cellular system. In addition, they
provide communications in extreme situations that might cause failures in other
communications network, like 2G or 3G. As a result of the analysis of the main digital PMR
standards (TETRA and DMR) used in European countries, we decided to use the DMR
standard to design the radio network for 118 service in Sardinia and for Civil Protection
service. DMR has been identified as the best solution, which grants cost saving, high
coverage, spectral efficiency and simplicity in network configuration and it is well suitable in
wide area with a low/medium density of traffic.
- The second and third chapter of the thesis are focused on improvement of the safety of
operators in a maritime cargo terminal. Hence, a new infrastructure of a maritime cargo
terminal has been defined, using a control system for monitoring workplace safety. By
combining, in the control system, the inputs from a Body Area Network (BAN) integrated in
the safety equipment and from CCTV cameras, a human supervisor is able to achieve an
accurate overview of the entire situation in terms of work safety and act accordingly when
needed. In addition, we focused even on the design and implementation of a working
prototype of an RFID-based BAN sensor network for actively monitoring and preventing
workplace safety risks in the same industrial area. This first conceptual and technological
analysis, together with the test implementation, is the forerunner of a complex monitoring
system in development to be implemented both for the specific case and for any industrial
environment.
- The last chapter aims to describe an indoor navigation system developed for smartphone
android. Specifically, it has been demonstrated how the use of a gyroscope sensor can brings
more benefits respect to a compass sensor to get the best detected position.
Nowadays, modern mobile devices, such as smartphones and PDAs in general, come to the market
already equipped with sensors able to track them as they move, both in outdoor and indoor
environment. The sensing technologies embedded in such devices make it ideal for a wide range of
location-based services, such as navigation applications. An Inertial Navigation System (INS) uses
motion and rotation sensors in order to determine the position, orientation, and velocity of a moving
object/user without the need of external infrastructures. This is essential in an indoor environment
where common localization systems, such as Global Positioning System (GPS), fail due to severe
attenuation or obscuration of the satellite's signal. In inertial navigation systems, localization/
orientation estimation is source-independent. The user's position is calculated in relation to a known
starting position using a dead reckoning algorithm and the orientation is usually provided by a
digital compass embedded in the smartphone. A digital compass sensor provides the orientation of
the device relative to the magnetic north of the earth. However, when it is used in indoor
environments, like any magnetic device, it is affected by significant error caused by nearby ferrous
materials, as well as local electromagnetic fields. Such errors seriously affect the performance and
the accuracy of the system, thus the need to investigate any alternative orientation technique. In the
specific, we have developed an early prototype of a pedestrian navigation system for indoor
environments based on dead reckoning, 2D barcodes and data from accelerometers and
magnetometers. All the sensing and computing technologies of our solution are available in
common smartphones. The prototype has been further improved by a new algorithm described
afterwards and now it is able to estimate the correct current position of the user, track him inside the
building and provide the best path to achieve a specific destination