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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Development of new analytical procedures aimet at the characterization of artistic samples

Bonacini, Irene <1984> 08 April 2015 (has links)
In this thesis, new advances in the development of spectroscopic based methods for the characterization of heritage materials have been achieved. As concern FTIR spectroscopy new approaches aimed at exploiting near and far IR region for the characterization of inorganic or organic materials have been tested. Paint cross-section have been analysed by FTIR spectroscopy in the NIR range and an “ad hoc” chemometric approach has been developed for the elaboration of hyperspectral maps. Moreover, a new method for the characterization of calcite based on the use of grinding curves has been set up both in MIR and in FAR region. Indeed, calcite is a material widely applied in cultural heritage, and this spectroscopic approach is an efficient and rapid tool to distinguish between different calcite samples. Different enhanced vibrational techniques for the characterisation of dyed fibres have been tested. First a SEIRA (Surface Enhanced Infra-Red Absorption) protocol has been optimised allowing the analysis of colorant micro-extracts thanks to the enhancement produced by the addition of gold nanoparticles. These preliminary studies permitted to identify a new enhanced FTIR method, named ATR/RAIRS, which allowed to reach lower detection limits. Regarding Raman microscopy, the research followed two lines, which have in common the aim of avoiding the use of colloidal solutions. AgI based supports obtained after deposition on a gold-coated glass slides have been developed and tested spotting colorant solutions. A SERS spectrum can be obtained thanks to the photoreduction, which the laser may induce on the silver salt. Moreover, these supports can be used for the TLC separation of a mixture of colorants and the analyses by means of both Raman/SERS and ATR-RAIRS can be successfully reached. Finally, a photoreduction method for the “on fiber” analysis of colorant without the need of any extraction have been optimised.
52

An Innovation System Perspective on Adaptation Strategies to Climate Variability and Water Management in India

Banerjee, Rupsha <1980> 24 October 2013 (has links)
Government policies play a critical role in influencing market conditions, institutions and overall agricultural productivity. The thesis therefore looks into the history of agriculture development in India. Taking a political economy perspective, the historical account looks at significant institutional and technological innovations carried out in pre- independent and post independent India. It further focuses on the Green Revolution in Asia, as forty years after; the agricultural community still faces the task of addressing recurrent issue of food security amidst emerging challenges, such as climate change. It examines the Green Revolution that took place in India during the late 1960s and 70s in a historical perspective, identifying two factors of institutional change and political leadership. Climate change in agriculture development has become a major concern to farmers, researchers and policy makers alike. However, there is little knowledge on the farmers’ perception to climate change and to the extent they coincide with actual climatic data. Using a qualitative approach,it looks into the perceptions of the farmers in four villages in the states of Maharashtra and Andhra Pradesh. While exploring the adaptation strategies, the chapter looks into the dynamics of who can afford a particular technology and who cannot and what leads to a particular adaptation decision thus determining the adaptive capacity in water management. The final section looks into the devolution of authority for natural resource management to local user groups through the Water Users’ Associations as an important approach to overcome the long-standing challenges of centralized state bureaucracies in India. It addresses the knowledge gap of why some local user groups are able to overcome governance challenges such as elite capture, while others-that work under the design principles developed by Elinor Ostrom. It draws conclusions on how local leadership, can be promoted to facilitate participatory irrigation management.
53

Tra società informazionale e prosumerismo: il citizen journalism e la partecipazione on line / Between information society and prosumerism: the citizen journalism and the on line involvement

di Capua, Danilo <1981> 13 June 2012 (has links)
I temi della ricerca riguardano il rapporto fra avvento del web e la modificazione dei processi di formazione di identità personale e sociale, della percezione dello spazio e del tempo, del prosumerismo digitale e delle varie forme di partecipazione ed associazione. Centrale è stata l’analisi del rapporto fra il Web 2.0 e la trasformazione delle forme di comunicazione a vari livelli, sia personali che sociali. Partendo da una analisi dei contesti socio-economici globali che hanno trasformato la società moderna nella società informazionale, è stato impostato un percorso di ricerca che approfondisse gli attuali criteri di strutturazione della propria identità, alla luce dell’avvento dei social network e delle reti virtuali di comunicazione come strumento preferenziale di socializzazione. La realtà delle reti sociali è stata analizzata in un’ottica di aggregazione spontanea mirata tanto alla comunicazione quanto alla tutela dei consumatori, e le trasformazioni portate dal Web 2.0 sono state la chiave di lettura per ridefinire i parametri della partecipazione dal basso generata dalla rete. Per comprendere la portata di tali trasformazioni nel contesto italiano è stato impostato un paragone tra l’uso del web negli Stati Uniti e in Italia, avendo le recente campagne elettorali dimostrato l’importanza del web nella partecipazione politica bottom-up; il percorso di ricerca ha dunque affrontato una comparazione di due casi, quello italiano e quello statunitense, finalizzato a comprendere l’attuale ruolo dell’utente nelle dinamiche di comunicazione mediatica. Per focalizzare al meglio le trasformazioni sociali generate dalla partecipazione on line è stato infine analizzato il caso del citizen journalism, per misurare, attraverso la metodologia dell’etnografia digitale, l’entità delle trasformazioni in corso. Il portale di giornalismo partecipativo YouReporter è stato il contesto privilegiato dove poter verificare le ipotesi iniziali circa le dinamiche di partecipazione, e il supporto di programmi di elaborazione statistica netnografica ha permesso di destrutturare al meglio tali dinamiche. / The subjects of the research concern the relationship between the growth of the web and the modification of the molding of personal and social identity, the perception of space and time, the digital prosumerism and the various patterns of participation and association. The project delves into the relationship between the Web 2.0 and the transformation of communication at various levels, both personal and social.The project focuses on the steps of the identity growth process, through the social network society, analyzing the social and economical contests that brought modern society to evolve into information society. Social networks have been studied as instruments for both socialization and consumerism, and as contest where to grow a new trend of popular participation. In order to clarify the subject and circumscribe the hypothesis of the research, the project structures a comparison between the use of the web in USA and Italy, with the purpose of understanding the current role of the web user in mass communication. In the research it was important to study the citizen journalism phenomenon in order to verify the hypotheses, through the methodology of digital ethnography, focusing on YouReporter website. Various programs of statistical elaboration supported the study of the “web galaxy”, analyzing the contest and destructuring the Web 2.0 reality.
54

Development Aid to Water Management in Mali: The Actors, ‘Global’ Paradigms, and ‘Local’ Translations

Cherlet, Jan Louisa Herman <1981> 05 July 2012 (has links)
Development aid involves a complex network of numerous and extremely heterogeneous actors. Nevertheless, all actors seem to speak the same ‘development jargon’ and to display a congruence that extends from the donor over the professional consultant to the village chief. And although the ideas about what counts as ‘good’ and ‘bad’ aid have constantly changed over time —with new paradigms and policies sprouting every few years— the apparent congruence between actors more or less remains unchanged. How can this be explained? Is it a strategy of all actors to get into the pocket of the donor, or are the social dynamics in development aid more complex? When a new development paradigm appears, where does it come from and how does it gain support? Is this support really homogeneous? To answer the questions, a multi-sited ethnography was conducted in the sector of water-related development aid, with a focus on 3 paradigms that are currently hegemonic in this sector: Integrated Water Resources Management, Capacity Building, and Adaptation to Climate Change. The sites of inquiry were: the headquarters of a multilateral organization, the headquarters of a development NGO, and the Inner Niger Delta in Mali. The research shows that paradigm shifts do not happen overnight but that new paradigms have long lines of descent. Moreover, they require a lot of work from actors in order to become hegemonic; the actors need to create a tight network of support. Each actor, however, interprets the paradigms in a slightly different way, depending on the position in the network. They implant their own interests in their interpretation of the paradigm (the actors ‘translate’ their interests), regardless of whether they constitute the donor, a mediator, or the aid recipient. These translations are necessary to cement and reproduce the network.
55

Chemistry of aerosol particles and fog droplets during fall-winter season in the Po Valley

Giulianelli, Lara <1978> 05 May 2014 (has links)
Air quality represents a key issue in the so-called pollution “hot spots”: environments in which anthropogenic sources are concentrated and dispersion of pollutants is limited. One of these environments, the Po Valley, normally experiences exceedances of PM10 and PM2.5 concentration limits, especially in winter when the ventilation of the lower layers of the atmosphere is reduced. This thesis provides a highlight of the chemical properties of particulate matter and fog droplets in the Po Valley during the cold season, when fog occurrence is very frequent. Fog-particles interactions were investigated with the aim to determine their impact on the regional air quality. Size-segregated aerosol samples were collected in Bologna, urban site, and San Pietro Capofiume (SPC), rural site, during two campaigns (November 2011; February 2013) in the frame of Supersito project. The comparison between particles size-distribution and chemical composition in both sites showed the relevant contribution of the regional background and secondary processes in determining the Po Valley aerosol concentration. Occurrence of fog in November 2011 campaign in SPC allowed to investigate the role of fog formation and fog chemistry in the formation, processing and deposition of PM10. Nucleation scavenging was investigated with relation to the size and the chemical composition of particles. We found that PM1 concentration is reduced up to 60% because of fog scavenging. Furthermore, aqueous-phase secondary aerosol formation mechanisms were investigated through time-resolved measurements. In SPC fog samples have been systematically collected and analysed since the nineties; a 20 years long database has been assembled. This thesis reports for the first time the results of this long time series of measurements, showing a decrease of sulphate and nitrate concentration and an increase of pH that reached values close to neutrality. A detailed discussion about the occurred changes in fog water composition over two decades is presented.
56

Integration of MFA and LCA methodologies: the anthropogenic aluminium cycle in Italy

Ciacci, Luca <1984> 12 April 2013 (has links)
MFA and LCA methodologies were applied to analyse the anthropogenic aluminium cycle in Italy with focus on historical evolution of stocks and flows of the metal, embodied GHG emissions, and potentials from recycling to provide key features to Italy for prioritizing industrial policy toward low-carbon technologies and materials. Historical trend series were collected from 1947 to 2009 and balanced with data from production, manufacturing and waste management of aluminium-containing products, using a ‘top-down’ approach to quantify the contemporary in-use stock of the metal, and helping to identify ‘applications where aluminium is not yet being recycled to its full potential and to identify present and future recycling flows’. The MFA results were used as a basis for the LCA aimed at evaluating the carbon footprint evolution, from primary and electrical energy, the smelting process and the transportation, embodied in the Italian aluminium. A discussion about how the main factors, according to the Kaya Identity equation, they did influence the Italian GHG emissions pattern over time, and which are the levers to mitigate it, it has been also reported. The contemporary anthropogenic reservoirs of aluminium was estimated at about 320 kg per capita, mainly embedded within the transportation and building and construction sectors. Cumulative in-use stock represents approximately 11 years of supply at current usage rates (about 20 Mt versus 1.7 Mt/year), and it would imply a potential of about 160 Mt of CO2eq emissions savings. A discussion of criticality related to aluminium waste recovery from the transportation and the containers and packaging sectors was also included in the study, providing an example for how MFA and LCA may support decision-making at sectorial or regional level. The research constitutes the first attempt of an integrated approach between MFA and LCA applied to the aluminium cycle in Italy.
57

Valutazione della mobilita' di contaminanti inorganici tramite test di cessione su matrici ambientali contaminate / Evaluation of inorganic contaminant's mobility by leaching test on polluted environmental materials

Corticelli, Claudio <1986> 09 April 2014 (has links)
La caratterizzazione di sedimenti contaminati è un problema complesso, in questo lavoro ci si è occupati di individuare una metodologia di caratterizzazione che tenesse conto sia delle caratteristiche della contaminazione, con analisi volte a determinare il contenuto totale di contaminanti, sia della mobilità degli inquinanti stessi. Una adeguata strategia di caratterizzazione può essere applicata per la valutazione di trattamenti di bonifica, a questo scopo si è valutato il trattamento di soil washing, andando ad indagare le caratteristiche dei sedimenti dragati e del materiale in uscita dal processo, sabbie e frazione fine, andando inoltre a confrontare le caratteristiche della sabbia in uscita con quelle delle sabbie comunemente usate per diverse applicazioni. Si è ritenuto necessario indagare la compatibilità dal punto di vista chimico, granulometrico e morfologico. Per indagare la mobilità si è scelto di applicare i test di cessione definiti sia a livello internazionale che italiano (UNI) e quindi si sono sviluppate le tecnologie necessarie alla effettuazione di test di cessione in modo efficace, automatizzando la gestione del test a pHstat UNI CEN 14997. Questo si è reso necessario a causa della difficoltà di gestire il test manualmente, per via delle tempistiche difficilmente attuabili da parte di un operatore. Le condizioni redox influenzano la mobilità degli inquinanti, in particolare l’invecchiamento all’aria di sedimenti anossici provoca variazioni sensibili nello stato d’ossidazione di alcune componenti, incrementandone la mobilità, si tratta quindi di un aspetto da considerare quando si individuano le adeguate condizioni di stoccaggio-smaltimento, si è eseguita a questo scopo una campagna sperimentale. / The characterization of contaminated sediments is a daedalean problem , in this paper the focus is to identify a method of characterization that takes into account both the characteristics of the contamination, with analysis to determine the total content of contaminants, and the mobility of the pollutants themselves. An adequate characterization strategy can be applied for the evaluation of managing options, and treatments of reclamation, for this purpose , it is assessed the treatment of soil washing, taking account of the characteristics of the sediment and dredged material in the process output, sands and fine fraction, and also to comparing the characteristics of the sand in output with those of sands commonly used for different applications. It was considered necessary to investigate the compatibility from the chemical point of view, particle size and morphology. Different leaching test have been applied to investigate the mobility, they are defined in the international and Italian norms (UNI) and therefore have developed the technologies necessary to carry out tests of the sale effectively, automating the management of test pHStat CEN 14997. That has been helpful due to the type of test, which is difficult to handle in manual way. The redox conditions affect the mobility of pollutants , in particular the aging of anoxic sediments in air causes substantial changes in the oxidation state of some components , increasing mobility , it is therefore an aspect to be considered when identifying the appropriate conditions storage - disposal. With that goal a series of experiments have been carried out.
58

Elf magnetic field influence on ION Channels studied by Patch Clamp Technique: exposure set up and "Whole Cell" measurements on Potassium currents

Gavoci, Entele <1976> 21 May 2009 (has links)
The aim of this thesis was to study the effects of extremely low frequency (ELF) electromagnetic magnetic fields on potassium currents in neural cell lines ( Neuroblastoma SK-N-BE ), using the whole-cell Patch Clamp technique. Such technique is a sophisticated tool capable to investigate the electrophysiological activity at a single cell, and even at single channel level. The total potassium ion currents through the cell membrane was measured while exposing the cells to a combination of static (DC) and alternate (AC) magnetic fields according to the prediction of the so-called ‘ Ion Resonance Hypothesis ’. For this purpose we have designed and fabricated a magnetic field exposure system reaching a good compromise between magnetic field homogeneity and accessibility to the biological sample under the microscope. The magnetic field exposure system consists of three large orthogonal pairs of square coils surrounding the patch clamp set up and connected to the signal generation unit, able to generate different combinations of static and/or alternate magnetic fields. Such system was characterized in term of field distribution and uniformity through computation and direct field measurements. No statistically significant changes in the potassium ion currents through cell membrane were reveled when the cells were exposed to AC/DC magnetic field combination according to the afore mentioned ‘Ion Resonance Hypothesis’.
59

Role of the Virtual Stakeholders in the Search of a Balance between Environment, Economy and Society in the Policy Choices Management

Tomasello, Bruno <1985> January 1900 (has links)
The PhD Thesis develops a pre-quantitative methodology to define the direct and indirect effects of policy choices concerning the environment. The main purpose has been to contribute to the solution of some of the problems affecting expert-based judgements: in particular, the dependence on the observer’s goals and beliefs (Reflexivity) and the possibility of making prevalent and accepted an extraneous and non-sustainable solution (Perspectivity). "Policy Choices Analysis and Synthesis System 42" (PoChASSy42) methodology provides a framework which describes the environment through all the possible interactions between: "Individuals Interests", identified as the normative values of the Universal Declaration of the Human Rights; "Collective Interests" identified through the economic activities classified by the NACE system of EuroStat; "Ecosystem Services", identified through the Millennium Ecosystem Assessment studies. The elements which make up these spheres of interests are considered as virtual stakeholders, i.e. the representatives of the existence, intentions, motivations and interests that make up the environment. Both the virtual stakeholders and the possible interactions among them are represented in the PoChASSy42 through the development of an Adjacency Matrix and a Narrative Structure (graph). Using these tools, the expert can: find the virtual stakeholders involved in a given policy choice and exclude, declaring the motivations, those which are not present in the particular geographic context. A final report with the results allows for a transparent communication, which is fundamental in order to further counteract the side effects (Perspectivity and Reflectivity) of a reductionist vision of the environment and to accept the challenge of complexity.
60

Metodi predittivi per Adaptive Radiation Theraphy: effetti del movimento d'organo, degli algoritmi di registrazione deformabile e dell'accumulo di dose / Predictive methods for Adaptive Radiation Therapy: effects of the organ motion, of the deformable registration algorithms and of the dose accumulation.

Guidi, Gabriele <1974> 06 April 2016 (has links)
Il lavoro di ricerca è finanziato dal Ministero della Salute - Bando Giovani Ricercatori 2010 MoH (GR-2010-2318757) “Dose warping methods for IGRT and Adaptive RT: dose accumulation based on organ motion and anatomical variations of the patients during radiation therapy treatments”. La ricerca ha sviluppato metodi predittivi per Adaptive Radiation Therapy. Il paziente è soggetto a macro-micro variazioni anatomiche intra-inter frazione e funzionali durante le fasi di preparazione del piano terapeutico e la ripetitività durante le sedute di radioterapia sono affette da fattori quali movimento d’organo e variazione morfologica, che possono influenzare il programma terapeutico. I sistemi avanzati di calcolo e accumulo di dose consentono la registrazione delle dosi erogate, tenendo in considerazione variazioni locali e globali. Il ricorso a tecnologiche e risorse umane infinite per verificare, istante per istante, la dose erogata a un singolo paziente, sarebbero impensabili nella pratica clinica. I modelli predittivi mediante reti neurali o epidemiologici contribuiscono al monitoraggio del paziente, mediante metodi fisici e statistici. Sono stati valutati fattori di movimento d’organo, le variazioni anatomiche, la deformazione delle immagini e l’accumulo di dose come principali elementi ed effetti nell’utilizzo di metodi predittivi. Questi fattori richiedono la validazione e sviluppo, mediante analisi Bayesiane e misure sperimentali che confermino qualità e accuratezza degli algoritmi. Lo sviluppo e utilizzo di metodiche di dose accumulation e la verifica delle dosi erogate, considerando movimento e deformazione, ha portato allo sviluppo di prototipi robotici, per dosimetria in-vivo e valutazione del movimento, mediante LEGO®. Lo sviluppo delle reti neurali, delle metodiche epidemiologiche e di Support Vector Machine ha consentito di estendere, mediante un progetto di data-mining, le metodologie a centri di livello nazionale. La ricerca mostra le criticità dei metodi predittivi dimostrando l’efficienza delle reti neurali e modelli epidemiologici, nei trattamenti avanzati del tumore della testa e collo, prostata, pancreas e polmone. / The research is funded by the Ministry of Health - Young Researchers in 2010 MoH (GR-2010-2318757) "Dose warping methods for IGRT and Adaptive RT: dose accumulation based on organ motion and anatomical variations of the patients during radiation therapy treatments". The research has developed predictive methods for Adaptive Radiation Therapy. The patient is subjected to macro-micro anatomical and functional variations during the preparation of the treatment plan and during radiation therapy treatments. They are affected by factors such as organs movement and morphological variations, which may influence the therapeutic program. The advanced systems for dose calculation and accumulation allow the recording of doses delivered, taking into account local and global variations. The use of technological and human resources endless to check, moment by moment, the dose delivered to an individual patient, would be unthinkable in clinical practice. Predictive models using neural networks or epidemiological contribute to the monitoring of the patient by physical and statistics methods. Were evaluated factors of organ motion, anatomical variations, deformable registration and dose accumulation as principal elements and effects in the use of predictive methods. These factors require validation and development, using Bayesian analysis and experimental measurements that confirm the quality and accuracy of the algorithms. The development and use of methods of dose accumulation and verification of doses delivered, considering movement and deformation, has led to the development of robotic prototypes for in-vivo dosimetry and evaluation of the movement, using LEGO. The development of neural networks, of epidemiological methods and Support Vector Machine have allowed extending, by means of a data-mining project, the methodologies in nationwide centers. Research shows the criticality of predictive methods proving the efficiency of neural networks and epidemiological models, for advanced treatments of the head and neck, prostate, pancreas and lung cancer.

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