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Polarimetric SAR for the monitoring of agricultural crops
Get PDFThe monitoring of agricultural crops is a matter of great importance. Remote
sensing has been unanimously recognized as one of the most important techniques for
agricultural crops monitoring. Within the framework of active remote sensing, the
capabilities of the Synthetic Aperture Radar (SAR) to provide fine spatial resolution
and a wide area coverage, both in day and night time and almost under all weather
conditions, make it a key tool for agricultural applications, including the monitoring
and the estimation of phenological stages of crops. The monitoring of crop phenology
is fundamental for the planning and the triggering of cultivation practices, since
they require timely information about the crop conditions along the cultivation
cycle. Due to the sensitivity of polarization of microwaves to crop structure and
dielectric properties of the canopy, which in turn depend on the crop type, retrieval
of phenology of agricultural crops by means of polarimetric SAR measurements is
a promising application of this technology, especially after the launch of a number
of polarimetric satellite sensors.
In this thesis C-band polarimetric SAR measurements are used to estimate pheno-
logical stages of agricultural crops. The behavior of polarimetric SAR observables
at different growth stages is analyzed and then estimation procedures, aimed at the
retrieval of such stages, are defined.
The second topic on which this thesis is focused on is the land cover types discrimi-
nation by means of X-band multi-polarization SAR data
Substrati artificiali per gli interventi di ripristino ambientale in aree contaminate da metalli pesanti
Get PDFMining activities can have a large local impact on the environment, in particular for the soils the problems are toxicity, high concentrations of heavy metals and low concentrations of nutrients and they are the cause of the difficulty in the development of plant species in these areas. In order to perform an environmental restoration, in these areas it is necessary to intervene on the ground by means of the substrates that are able to support the development of the vegetation (Tordoff et al., 2000).
In mining areas it is necessary to intervene with the substrates to enhance growth of vegetation (Tordoff et al., 2000).
In Sardinia, the mining activity has caused big changes of the territory with consequent problems of degradation and environmental impact. The problem of management of industrial structures and of the enormous amount of deposits of potentially polluting materials are created by the cessation of mining activities (Bacchetta et al., 2007).
The purpose of this work is to study the development of methodologies, using a technical-scientific approach to use man-made substrates in environmental restoration in areas contaminated by heavy metals. This objective was pursued through the study of different man-made substrates, obtained by mixing different percentages of contaminated soil with dedicated substrates. The dedicated substrates were obtained by mixing different raw materials according to specific proportions.
The considered disused mining area is that of Montevecchio, western Sardinia, in the area of Sulcis-Iglesias-Guspinese, identified as the site of reclamation of national interest (DM 468/01) and bounded by Decree of the Ministry of Environment and Protection of Land and Sea of 12 March 2003 (Plan Reclamation of disused mining areas of Sulcis-Iglesias-Guspinese, 2008).
The contaminated soil was collected from the tailings pond in the mine of Montevecchio. After an analysis of previous studies and a careful bibliographic search, it was decided to use like plant species: Artemisia arborescens L. (Fam. Asteraceae), a native plant and colonizing plant; the Nerium oleander, a perennial plant that can be sampled throughout the year and the Populus Nigra L. Italica, a fast-growing species with a percentage of rooting for vegetative reproduction of 65%.
All individuals of the populations used in the experiment were obtained through the taking of clones from mother plants growned in the wild. Subsequently the selected plants were propagated by agamic reproduction, through cuttings. The cuttings were grown in the greenhouse in plateaux and after rooting, were transplanted into pots, previously filled with the man-made substrate. The clones were placed in the greenhouse, in conditions of controlled temperature and humidity and regularly irrigated by drip. Weekly have been verified the plant health condition and the growth of the aerial
part by detecting heights of plants by measuring the distance between the plane of the edge of the pot and the apical part of the plant.
For each man-made substrate it was determined the content of C, H and N, pH, CSC, EC, the content of heavy metals and nutrients. The efficiency of the substrates were determined by the development of the growth curves, obtained by the mean value of the parameter biometric height.
By the comparison between the curves it was possible to measure the influence of the genetic variability on the growth of different clonal populations planted in the same substrate and the influence of different substrate on the same clonal population
Interazioni neurotrasmettitoriali nel meccanismo d’azione della cocaina: ruolo della serotonina e dell’adenosina
Get PDFThe putative 5-HT6 receptor agonist ST1936 has been shown to increase extracellular
dopamine (DA) in the n.accumbens (NAc) Shell and in the medial prefrontal cortex (PFCX).
These observations suggest that 5-HT6 receptors modulate DA transmission in mesolimbic
and mesocortical terminal DA areas. To investigate the behavioral counterpart of this
interaction I studied in rats the effect of 5-HT6 receptor blockade on cocaine stimulated
overflow of DA in dialysates from the PFCX and from the NAc Shell and on cocaine i.v. selfadministration.
Pretreatment with the 5-HT6 antagonist SB271046 reduced cocaine-induced
increase of dialysate DA in the NAc Shell but not in the PFCX and impaired i.v. cocaine selfadministration.
These suggest that 5-HT6 receptors play a role in cocaine reinforcement via
their facilitatore interaction with DA projections to the NAc Shell. This 5-HT/DA interaction
might provide the basis for a new pharmacotherapeutic strategy of cocaine addiction.
Caffeine is one of the psychoactive substances most widely used as adulterant in illicit drugs,
such as cocaine. Animal studies have demonstrated that caffeine is able to potentiate cocaine
actions, although the enhancement of the cocaine reinforcing property by caffeine is less
reported, and the results depend on the paradigms and experimental protocols used.
In the present study I examined the ability of caffeine to enhance the motivational and
rewarding properties of cocaine using the intravenous self-administration paradigm in rats.
Additionally, the role of caffeine as a primer cue during extinction was evaluated. To this end,
we assessed in naïve rats: 1) the ability of the combination of cocaine (0,125
mg/kg/infusion) and caffeine (0,0625 mg/kg/infusion) to maintain self-administration in
fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement compared with cocaine
and caffeine alone; 2) the effect of caffeine in the maintenance of responding in the animals
exposed to the combination of the drugs during cocaine extinction.
Cocaine and the combination of cocaine and caffeine were self-administered on a FR and PR
schedules of reinforcement, and the responding for the combination of the drugs was higher
than cocaine alone. Caffeine was not reliably self-administered, but was able to maintain a
drug-seeking behavior in rats previously exposed to cocaine plus caffeine.
These findings suggest that the presence of caffeine enhances the reinforcing effects of
cocaine and the motivational value of the drug. Our results highlight the role of active
adulterants commonly used in illicit street drugs
Harmful effect of oxysterols in the gut and at systemic level: modulatory activity of olive oil phenolics
Get PDFA healthy and proper diet is essential to prevent the onset of various diseases, as with the diet we can also introduce harmful substances.
Among others, the oxysterols are particularly relevant; they can be absorbed from the diet and are the oxidized products of cholesterol present in cholesterol-containing foodstuffs after cooking, processing and storage, such as meat, fish, dairy products and eggs. They can be also generated endogenously from either the spontaneous or enzymatic oxidation of cholesterol.
Oxysterols have been shown to exert several in vitro and in vivo biochemical activities, physiological but mostly pathological. In particular, they may induce cytotoxicity, cell death (necrosis and apoptosis), pro-oxidant and pro-inflammatory effects in different cells and tissues and have been linked with the onset and development of major chronic diseases.
Only in the last few years, oxysterols have been shown to interfere with the homeostasis of the human digestive tract, demonstrating their involvement in the pathogenesis of human inflammatory bowel disease and colon rectal cancer.
Experimental studies suggest that the ingestion of compounds with antioxidant action, such as phenolics, is able to counteract the oxidative stress and inflammatory response in the intestine and inhibit the onset of the main related diseases.
Extra virgin olive oil polyphenols in particular, recognized for their strong antioxidant property and related anti-inflammatory action, may display this effect in the intestinal lumen where they concentrate before absorption, preventing intestinal diseases.
The first aim of this study was to evaluate the ability of different extra virgin olive oil phenolic extracts to counteract the pro-oxidant, pro-apoptotic and pro-
inflammatory action of oxysterols in the human colon adenocarcinoma cell line (Caco-2) and the molecular mechanism involved.
Oxysterols treatment, depending on time of exposure and concentrations used, significantly altered the cellular redox status (ROS production increase, GSH decrease, GPX activity enhancement), induced an oxidative damage to the membrane lipid fraction (MDA production increase) and cell death (Caspase 3 increase); cytokines production (IL-6, IL-8) was indicative of a pro-inflammatory effect. Phenolic extracts were able to significantly counteract the oxysterols harmful effects, at least in part by modulating intracellular signaling pathways (Akt/PKB, MAPK) involved in the cellular response to oxidative stress, apoptosis and inflammation.
Several studies in animals and humans have shown that dietary oxysterols, after digestion can be absorbed from the gut and transported into the circulation within chylomicrons and other lipoproteins. Furthermore, the presence of oxysterols in plasma can derive from the oxidation of endogenous cholesterol through enzymatic or spontaneous reactions.
Oxysterols have been found at increased levels in the plasma of hypercholesterolemic subjects and have been linked with the atherosclerotic process.
In this context the second part of this study was specifically focused on the protective effect of pure olive oil phenolics, which can be found in the blood stream after absorption (hydroxytyrosol, tyrosol, and homovanillc alcohol), against the pro-oxidant and pro-inflammatory activity of oxysterols in blood cells (PBMCs).
It was demonstrated that all phenolic compounds tested, HT, TYR and HVA were able to inhibit oxysterol-induced pro-inflammatory cytokines production.
According to the hypotesis that pro-inflammatory cytokine release may be induced by changes in intracellular redox status, it was observed that, in human
PBMCs treated with the oxysterols mixture, simple phenols were also able to inhibit ROS production as well as to suppress both redox-based MAPK phosphorylation (JNK, p38).
These data suggest that olive oil phenolic extracts may significantly contribute to preserve the integrity of intestinal mucosa against oxidative damage and inflammation related disorders and simple phenols found in the blood after metabolism and absorption counteract the oxysterols-induced inflammatory effect at systemic level
L'insegnamento della meccanica quantistica nella scuola secondaria: fondamenti, problemi, proposte
Get PDFQuantum mechanics isn’t just the theory that explains the atomic
and subatomic world, but also a great adventure of the human
thinking: since the beginning of the Twentieth Century it has deeply
changed the world view of scientists and philosophers. On these and
other reflections is based the importance of teaching modern physics
in the high school. By these considerations comes out a complicated
problem of research in physics education: the possibility and the way
we could teach modern physic in the period that comes before academic
studies. The problem has become more urgent since some latest
changes in the education law in Italy. The hypothesis of this project
of research is that teaching and learning of quantum mechanics meet
some obstacles that make difficult to implement the didactic proposals
developed by researchers. In the matter of students’ difficulties, are mainly studied the formal obstacles and the possibility of developing
didactic proposals with mathematic tools accessible for the
students. In the matter of teachers’ difficulties, is studied their view
of the problem, by means of an investigation into a teachers group
of a local high school and a wide investigation into a group who participated
in an important experience of nationwide training. From
the results of investigations arise very interesting reflections about
teachers training in modern physics education
Composizione corporea, nutrizione personalizzata e costo energetico della corsa: studio longitudinale su una popolazione di individui fisicamente attivi
Get PDFConsidering the relation between body weight-composition and energy cost of running, we tested
the hypothesis that modifying body composition by means of a combined protocol of specific diet
and training, the energy cost of motion (Cr) may be reduced. 45 healthy and normal-weight subjects
were divided into three groups that performed a different treatment: the first group attended only a
dietary protocol (D), the second only a running program (R) and the third both (R&D). Each subject
underwent three anthropometric and exercise evaluation tests during one year (at T0, T6, T12) to
assess body composition and Cr adjustments. The mean fat mass (FM) values were reduced in R&D
from 12.0±4.0 to 10.4±3.0 kg (p<0.05 T0 vs. T12) and in the D group from 14.2±5.8 to 11.6±4.7 kg
(p<0.05 T0 vs. T12). Conversely, the mean fat free mass values increased in R&D (from 56.3±8.8
to 58.3±9.8 kg, p<0.05 T0 vs. T12) and in the D group (from 50.6±13.2 to 52.9±13.6 kg, p<0.05 T0
vs. T12). The mean Cr values of the 2 groups were significantly modified throughout the one year
protocol (1.48±0.16 and 1.40±0.15 kcal·kg-b·km-1 in the R&D group at T0 and T12 respectively;
1.83±0.17 and 1.76±0.23 kcal·kg-b·km-1 in D group at T0 to T12 respectively). The R&D and D
groups that underwent the diet protocol had a positive change in body composition during the year
(FM-fat free mass ratio decline) which determined a Cr reduction
The discursive shaping of intellectual ownership: the case of James Watt and Josiah Wedgwood
Get PDFThis work focuses upon some differences and some similarities between James Watt and Josiah
Wedgwood's legitimation of their respective intellectual properties. More particularly I mean to
investigate the literary technologies involved in their discourses over authorship, originality,
invention and imitation. Such an analysis provides an outline of the principal cultural resources that
Watt and Wedgwood mobilized to defend their commercial interests
The multifaceted world of sustainability. An analysis of about 30 years of studies
Get PDFThe concept of sustainability has emerged as a response to the most
stringent problems of humanity. Initially defined in the Brundtland report
published by the World Commission on Environment and Development in
1987 as the “development that meets the needs of the present without
compromising the ability of future generations to meet their own needs”
(United Nations, 1987:43), sustainable development constituted the main
topic of the Conference on Environment and Development in Rio de Janeiro
in 1992. The conference distinguished itself in the world of academia by
establishing the principles of sustainable development and the indisputable
relation between three fundamental pillars: environmental protection, social
equity and economic development (Scrobota and Vosylius, 2013).
This dissertation is composed of three essays. Essay 1,
“Sustainability: The State of the Art and Emerging Perspectives”, analyzes
the current academic literature on sustainability, first, with elaborative
documentation and, second, using bibliometric analysis supported by the
Science Mapping Analysis Software Tool (SciMat) open source software
(Cobo, Lòpez-Herrera, Herrera and Herrera-Viedma, 2012b) to gain insight
on this body of knowledge and to investigate which topics are associated
with this subject and considered to be the most relevant.
Essay 2, “What Happens to Well-Being and Happiness by
Combining with Sustainability?”, originates from the results of Essay 1 and
develops an analysis of the relationship between sustainability, well-being
and happiness. Indeed, as outlined in Essay 1, a considerable amount of
literature has focused on environmental and economic dimensions, but there
is little systematic research on how sustainability can interact with these
factors as new paradigms for individuals, communities, and organizations.
Essay 2 contributes to extending the existing theories on the three
pillars of sustainability and identifies well-being and happiness as new
driving factors.
Essay 3, “Sustainability as a Matrix of Experiential Marketing”,
examines the current role of sustainability as a matrix of experiential
marketing to understand how a memorable, emotional and responsible
connection between consumers and sustainable brand can generate customer
loyalty and affect the purchase decision through a case study (Yin, 1984;
Eisenhardt and Graebner, 2007; Siggelkow, 2007; Yin, 2009) that analyzes
an ecological campaign called “The Fun Theory”. This work contributes to
strengthening this new theory, according to which “fun” is best for changing
the bad habits of people in a responsible and sustainable manner.
Collectively, the three essays provide a general picture for a more
holistic understanding of sustainability that creates new possibilities for
more focused and effective sustainable development policies. A broader
perspective on sustainability can maintain or improve the well-being and
happiness of human beings. Reaching this objective is possible if the
restrictions of individual freedoms, resource use and the ability to undergo
experiences are compensated by improvements in the other determinants of
wellness, and such improvements can be an effective motivator for sustainable behavior
Ambient vibration measurements for non-destructive evaluation of structures by means of seismic methods and ground-based microwave interferometry
Get PDFThis thesis collects the results of the researches carried out during the Ph.D. course in “Technologies for the Conservation of Architectural and Environmental Heritage” into the School of Civil Engineering and Architecture of the University of Cagliari. The main topics of this research are focused on the experimental dynamic analysis of the structures with prevalent, but not exclusive, interest for the analyses of historic structures. The research deals with several issues concerning both the experimental measurements and the relationships between vibration properties and structural features and materials.
The study starts with an introduction, developed into the first chapter, where the general principles of the experimental dynamic analysis methods of structures are presented and summarised, especially for the passive techniques based only on ambient vibrations records.
The next chapter presents and describes the main features of the Ground-based Radar Interferometry to perform remote measurements of vibrations, using the phase difference between reflected signals coming from the surface of the same object inside the radar scenario. This technique has been developed in relatively recent years and has seen a considerable spread thanks to the short time need for the measurements and for the capability to retrieve reliable time series of displacement without any contact sensors above the structures. Furthermore the vibration data, acquired with both conventional systems (such as seismic sensors, velocimeters, accelerometers, etc.) and the microwave interferometer IBIS-S (Image By Intereferometry Survey), have been compared.
Different case studies have been examined and critically discussed in the following chapters.
In particular, chapter three is focused on the analysis of the vibration properties of an earthquake damaged bell tower located near the epicenter of the Emilia earthquake. Both ex ante and ex post conditions respect to the seismic induced damage have been compared. For this purpose a non-contact dynamic survey has been carried out by means of the radar interferometry method. The campaign of measurements has been conducted after the earthquake to describe the dynamic behaviour of the structure with open fractures pattern and with significant structural damages. Finally, a Finite Element model of the structure has been done in order to compare the actual dynamic response of the tower with that one of the undamaged structure.
Chapter four looks at the influence of the vibration artificially induced by the coordinated movement of twenty people to improve main dynamic properties identification of the structure. In this case, the measurements have been carried out using the radar sensor by means of four stations located around the examined structure, the Leaning Tower of Pisa. The measurements have been performed in both operational mode using only wind induced vibrations and also with the artificial human forcing, applied at the top floor of the tower.
Chapter five describes both the experimental measurements and the numerical modelling carried out in order to derive the dynamic features of two similar bell towers. The comparison between the dynamic behaviour of the towers is aimed at studying the influence of the mechanical properties of different construction materials. In fact, the towers are symmetrically built on both sides of the main façade of a church but the two structures are made using different materials and with different construction techniques. The oldest tower is a stone masonry building and the second one is a Reinforced Concrete structure. In this case, the analyses have been carried out using vibration data acquired by means of both available systems, i.e. the IBIS-S radar interferometer for the
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measurements related to the upper parts of the structure (not easily accessible) and some seismic transducers for the stations located inside of the building.
Chapter six finally presents the vibration measurements performed on a double curvature arch dam with different reservoir water level in order to analyse the variation of the linear dynamic response of the structure related to the water level height on the upstream side of the dam. The experimental surveys are described and the comparison with a numerical modelling is shown
An intelligent diagnostic system for screening newborns
Get PDFThe goal of this research is to devise and develop an intelligent system for analyzing heart sound signals, able to support physicians in the diagnosis of heart diseases in newborns. Many studies have been conducted in recent years to automatically differentiate normal heart sounds from heart sounds with pathological murmurs using audio signal processing in newborns. Serious cardia pathology may exist without symp- toms. Since heart murmurs are the first signs of heart disease, we screen newborns for normal (innocent) and pathological murmurs. This thesis presents a variety of techniques in time-frequency domain such as Cepstrum, Shannon energy, Bispe trum, and Wigner Bispe trum for feature extraction. A comparison of these techniques is considered to feature selection which has been used to reduce the size of the feature vector. In the final step, different lassi ers and techniques, e.g., Multi layer perc eptron (MLP), decision tree, Classification and Regression Trees (CART) and ensemble of decision trees, are applied on data in order to a hieve highest performan e. High classifi cation accuracy, sensitivity, and specifity have been obtained on the given data by CART. The validation process has been performed on a balanced dataset of 116 heart sound signals taken from healthy and unhealthy medical cases