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Electrospun materials for energy applications: from Lithium-ion batteries to electretsZaccaria, Marco <1987> 21 March 2016 (has links)
The aim of this work is focused on the application of electrospinning technology, an innovative manufacturing technique to design nanostructured polymers, for energy storage, energy harvesting and sensor applications. These nanostructures are suitable to increase specific performances of components: from the reduction of internal resistance of Lithium-ion batteries to the increase of specific electrical response of materials for energy harvesting. The increase of specific power of Lithium-ion batteries represents one of the key factors for the development of competitive storage systems for automotive and power grid. Indeed, electrochemical performances at high currents significantly decay, strongly limiting the competitiveness on the market beyond portable applications. Furthermore, recovery of dissipated energy will be one of the most promising challenges for the establishment of green technologies and for the reduction in power consumption. Finally, health monitoring and/or impact sensors could represent suitable technologies for the growth of smart materials. This Ph.D. thesis covers the study of PVdF-based polymers to develop enhanced materials for Lithium-ion batteries and energy harvesters. / Questa tesi verte sull’applicazione della tecnica dell’electrospinning per realizzare polimeri nanostrutturati da impiegare nel campo dell’accumulo energetico, del recupero dell’energia dissipata e della sensoristica. Queste nanostrutture possono incrementare la risposta specifica dei componenti: dalla riduzione della resistenza interna delle batterie Litio-ione all’incremento della risposta elettrica specifica di materiali per il recupero dell’energia. L’incremento della potenza specifica delle batterie Litio-ione rappresenta una delle maggiori sfide per lo sviluppo di sistemi di taglia elevata, per applicazioni nel settore “automotive” e per l’accumulo in rete. Infatti le prestazioni elettrochimiche ad elevate correnti decadono significativamente, limitando fortemente la competitività di tali accumulatori al di fuori delle applicazioni portatili. Inoltre il recupero dell’energia dissipata rappresenta una delle strategie più promettenti per lo sviluppo di tecnologie a basso impatto ambientale e per la riduzione dei consumi energetici. Infine sensori di impatto o sistemi per l’”health monitoring” realizzati mediante tali nanostrutture possono contribuire sensibilmente allo sviluppo di “smart materials”. Questa tesi di Dottorato concerne dunque lo studio di polimeri fluorurati a base PVdF per lo sviluppo di materiali innovativi per batterie Litio-ione e per dispositivi per il recupero dell’energia.
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Integrazione di processi industriali in una prospettiva di economia circolare / Integration of industrial processes in a circular economy perspectiveMencherini, Ugo <1983> January 1900 (has links)
Le motivazioni alla base di questo lavoro di dottorato sono costituite dalla volontà di analizzare e applicare modelli innovativi per il ri-uso e la valorizzazione di risorse e sottoprodotti all’interno di processi industriali, integrando e ottimizzando i processi industriali stessi. L’obiettivo finale è stato quello di contribuire alla diffusione della “Cultura della Sostenibilità” in Emilia-Romagna, portando all’attenzione delle istituzioni l’esistenza di strumenti innovativi.
Lo studio si è concentrato sul contesto comunitario e locale in materia di Sviluppo Sostenibile, Green Economy ed Economia Circolare (Capitolo 1), per poi analizzare e classificare i modelli di Economia Circolare e Simbiosi Industriale esistenti (Capitolo 2). In una seconda fase dell’attività di dottorato, questo è stato applicato sperimentalmente sul territorio regionale, nell’ambito di un progetto pilota finanziato da Unioncamere Emilia-Romagna e Aster, realizzato in collaborazione con ENEA UTTAMB e con il coinvolgimento dei laboratori della Rete Alta Tecnologia dell’Emilia-Romagna (Capitolo 3). L’ultima fase è consistita nell’analisi dei risultati dell’esperienza pilota, delle risposte delle imprese e dei centri di ricerca, e nell’analisi delle altre esperienze condotte in Italia in materia di simbiosi, al fine di individuare dei parametri che influiscono sull’applicabilità e sulla replicabilità di questi modelli (Capitolo 4).
Tra i risultati principali ottenuti va citato l’inserimento della Simbiosi Industriale all’interno delle Smart Specialization Strategy – S3 dell’Emilia-Romagna e nel Piano Regionale di Gestione dei Rifiuti, oltre alla realizzazione di un progetto europeo in materia. Inoltre l’attività sperimentale pilota ha coinvolto 13 imprese, 7 laboratori e 2 enti, individuando 49 percorsi di simbiosi e 90 sinergie, portando alla redazione di 3 Manuali Operativi.
L’attività pilota sul tema della Simbiosi Industriale ha consentito di attivare numerosi contatti con imprese e istituzioni del territorio. A questi risultati vanno aggiunti anche quelli legati alla produzione scientifica: nel complesso sono state realizzate 13 pubblicazioni scientifiche e 1 pubblicazione divulgativa. / The motivations of this PhD work are constituted by the willingness to analyze and implement innovative models for resources re-use and valorization in production processes. The ultimate goal was to help the spreading of the “sustainability culture” in Emilia-Romagna region, bringing to the attention of the institutions the existence of innovative models.
The study focused on the EU and local context in matters of Sustainable Development, Green Economy and Circular Economy (Chapter 1), and on Circular Economy and Industrial Symbiosis (IS) models analysis and classification (Chapter 2). In a second phase of the PhD work, one selected model of Industrial Symbiosis was applied in Emilia-Romagna region, within the framework of a pilot project founded by Unioncamere Emilia-Romagna and Aster, realized with the collaboration of ENEA and the participation of laboratories pertaining to Emilia-Romagna High technology Network. In the last phase of the work the results of the pilot project and of other “circular economy experiences” in Emilia-Romagna were analyzed in order to identify the parameters that affect applicability and replicability of these models (Chapter 4).
The main results of the work consist in the insertion of Industrial Symbiosis in Emilia-Romagna Region Smart Specialization Strategy (S3) and Waste Management Plan and in the realization of a European project on IS topic participated by Emilia-Romagna Region. The experimental pilot activity, indeed, has successfully involved 13 companies, 7 laboratories and 2 institutions, and has led to the publication of 13 scientific papers and 1 dissemination article.
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Insulation Coordination in Modern Distribution NetworksTossani, Fabio <1988> 21 March 2016 (has links)
The appropriate analysis of the response of distribution networks against Lightning Electro Magnetic Pulse (LEMP) – originated by nearby strikes – requires the availability of accurate coupling models in order to reproduce the real and complex configuration of distribution systems.
The above models represent a fundamental tool for estimating the number of protective devices and their most appropriate location in order to guarantee a given minimum number of flashovers and outages per year. When dealing with real networks, such an optimization could require huge computational efforts due to the vast number of power components and feeders. This thesis thoroughly analyzes many of the possible engineering simplifications that, without losing accuracy, can be adopted in the statistical evaluation of the lightning performance of distribution networks in order to limit computational times.
Particular attention is devoted to the effect of the ground conductivity on the LEMP and on the line parameters; two new analytical expressions for the evaluation of the inverse Laplace transform of the ground impedance matrix elements of multiconductor overhead lines are derived. The first expression is the inverse Laplace transform of Sunde’s logarithmic formula and is given in two equivalent forms. The second expression is the inverse Laplace transform of Sunde’s general integral expression.
Finally, a procedure able to evaluate the lightning performance of a real medium-voltage distribution network, which includes several lines, transformers and surge protection devices is developed and proposed for the analysis of some real cases. Such a procedure allows inferring the characteristics of the statistical distributions of lightning-originated voltages at any point and phase of the network. The analysis aims at assessing the expected mean time between failures of transformers caused by both direct and indirect lightning strikes. / L'analisi della risposta di una rete elettrica di distribuzione a un campo elettromagnetico esterno generato da una scarica atmosferica richiede l'utilizzo di accurati modelli in grado di riprodurre la reale e complessa configurazione della rete.
Tali modelli rappresentano uno strumento fondamentale per la stima del numero di dispositivi di protezione ed il loro appropriato collocamento al fine di garantire il numero minimo annuo di “flashovers” e interruzioni. In una rete di distribuzione reale, tale ottimizzazione può richiedere sforzi computazionali proibitivi a causa dell’elevatissimo numero di componenti di potenza e linee presenti. Questa tesi analizza in maniera esaustiva molteplici semplificazioni ingegneristiche adottabili, al fine di ridurre i tempi computazionali, nella valutazione statistica del numero annuo di guasti di una rete di distribuzione.
Particolare attenzione è dedicata agli effetti della conducibilità finita del suolo sul campo irradiato dal fulmine e sui parametri delle linee. Nella tesi sono derivate due nuove espressioni analitiche per il calcolo della trasformata di Laplace inversa dell’impedenza del terreno. La prima è la trasformata di Laplace inversa dell’espressione di Sunde logaritmica ed è proposta in due forme equivalenti. La seconda è la trasformata di Laplace inversa della più generale espressione integrale di Sunde.
Infine, si è sviluppata una procedura in grado di valutare la “lightning performance” di una rete di distribuzione in media tensione avente configurazione realistica, che comprende “feeder” principali e laterali, pali, cabine secondarie e dispositivi di protezione contro le sovratensioni. La procedura messa a punto, basata sull’applicazione del metodo di Monte Carlo, permette di calcolare l'ampiezza delle tensioni indotte da fulminazione in qualsiasi punto e in ogni fase della rete. L’attività ha riguardato anche la valutazione del tempo medio fra i guasti (MTBF) di ogni trasformatore MT / BT causati da fulminazione indiretta e diretta, parametro di fondamentale rilevanza per l’ente distributore.
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Variabilitat i patrons funcionals en els sistemes tècnics de mode 2. Anàlisi de les deformacions d'ús en els conjunts lítics del Riparo Esterno de Grotta Paglicci (Rigano Garganico, Foggia), Aridos (Arganda, Madrid) i Galeria-TN (Atapuerca, Burgos)Ollé Cañellas, Andreu 06 February 2003 (has links)
- RESUMEN - ABSTRACT RESUM La tesi que porta per títol Variabilitat i patrons funcionals en els sistemes tècnics de mode 2. Anàlisi de les deformacions d'ús en els conjunts lítics del Riparo Esterno de Grotta Paglicci (Rignano Garganico, Foggia), Áridos (Arganda, Madrid) i Galería-TN (Sierra de Atapuerca, Burgos), està centrada en l'estudi de la funció dels instruments lítics i en com aquestes dades poden aportar informació sobre la variabilitat tècnica dels conjunts acheulians. El treball consta de dues parts ben diferenciades. La primera està dedicada als aspectes metodològics, que inclouen el marc teòric del nostre sistema d'anàlisi (el Sistema Lògic Analític), els plantejaments bàsics de l'estudi funcional (amb especial èmfasi en la utilització del Microscopi Electrònic de Rastreig -MER- com a tècnica d'onservació), l'explicació de les bases del nostre programa experimental, i un apartat amb un estat de la qüestió sobre els principals aspectes relatius a la interpretació de les deformacions d'ús en instruments arqueològics. A continuació, presentem detalladament l'experimentació portada a terme i els resultats obtinguts, per acabar amb el plantejament d'un model interpretatiu dels processos de desgast en objectes lítics. A la segona part, donem pas a la presentació dels jaciments acheulians estudiats: el Riparo Esterno de Grotta Paglicci, els dos conjunts d'Áridos, i, finalment, el de Galería-TN. En cadascun dels capítols corresponents s'ofereix una presentació general del jaciment i una descripció global del conjunt lític, i es mostres i discuteixen els resultats funcionals obtinguts, per acabar amb una recapitulació i unes conclusions específiques per a cada cas. Abans de presentar les conclusions, incloem un capítol de discussió, on es valoren els resultats de l'anàlisi funcional, es confirma la viabilitat d'aquest tipus d'estudi, es comparen els resultats obtinguts en els diferents jaciments analitzats i es mostra de quina forma aquestes dades permeten afrontar el tema de la variabilitat tècnica acheuliana. A les conclusions, en primer lloc, recollim els principals avenços metodològics fruit de la nostra recerca. Confirmem la possibilitat de reconèixer accions i activitats realitzades amb eines antigues a través de l'estudi mitjançant el MER del desgast, assenyalem la importància de disposar d'un ampli programa experimental, i proposem un model interpretatiu segons el qual l'esmentat desgast s'explica per fenòmens bàsicament atricionals, en els quals la deformació plàstica dels materials lítics hi està plenament contemplada. Quant als resultats arqueològics, s'han identificat bàsicament activitats relacionades amb la carnisseria, però també amb el tractament de la pell i accions sobre matèries vegetals. Les dades obtingudes han permès avançar en la interpretació de les ocupacions humanes que generaren el registre de cada jaciment estudiat, així com explicar part de la variabilitat tècnica present en els conjunts de mode 2, en funció de les característiques de l'enclau on es localitza el jaciment (aire lliure, abric o cova), de la immediatesa dels recursos lítics i alimentaris, de les activitats portades a terme i de la planificació tècnica reflectida en el registre arqueològic. Concloem la tesi amb la proposta de futures línies de recerca relacionades amb l'anàlisi funcional d'eines de pedra, com són l'avenç en el model interpretatiu de la deformació de materials lítics (mitjançant la realització d'experiments que permetin quantificar satisfactòriament els processos observats), el tractament estadístic de les variables considerades essencials, i el plantejament de protocols d'estudi on es combinin l'anàlisi del desgast amb el de residus. / La tesis doctoral titulada Variabilidad y patrones funcionales en los sistemas técnicos de modo 2. Análisis de las deformaciones por uso en los conjuntos líticos del Riparo Esterno de Grotta Paglicci (Rignano Garganico, Foggia), Áridos (Arganda, Madrid) y Galería-TN (Sierra de Atapuerca, Burgos), se centra en el estudio de la función de los instrumentos líticos y en cómo estos datos pueden aportar información acerca de la variabilidad técnica de los conjuntos achelenses. El trabajo consta de dos partes bien diferenciadas. La primera está dedicada a los aspectos metodológicos, que incluyen el marco teórico de nuestro sistema de análisis (el Sistema Lógico Analítico), los planteamientos básicos del estudio funcional (con especial hincapié en la utilización del Microscopio Electrónico de Barrido -MEB- como técnica de observación), la explicación de las bases de nuestro programa experimental, y un apartado con un estado de la cuestión sobre los principales aspectos relativos a la interpretación de las deformaciones por uso en instrumentos arqueológicos. A continuación, presentamos detalladamente la experimentación llevada a cabo y los resultados obtenidos, para terminar con el planteamiento de un modelo interpretativo de los procesos de desgaste en objetos líticos. En la segunda parte, damos paso a la presentación de los yacimientos achelenses estudiados: el Riparo Esterno de Grotta Paglicci, los dos conjuntos de Áridos, y, finalmente, el de Galería-TN. En cada uno de los capítulos correspondientes se ofrece una presentación general del yacimiento y una descripción global del conjunto lítico, y se muestran y discuten los resultados funcionales obtenidos, para acabar con una recapitulación y unas conclusiones específicas para cada caso. Antes de presentar las conclusiones, incluimos un capítulo de discusión, donde se valoran los resultados del análisis funcional, confirmando la viabilidad de este tipo de estudio, comparando los resultados obtenidos en los diferentes yacimientos analizados y viendo cómo estos datos permiten afrontar el tema de la variabilidad técnica achelense. En las conclusiones, en primer lugar, recogemos los principales avances metodológicos fruto de nuestra investigación. Confirmamos la posibilidad de reconocer acciones y actividades realizadas con instrumentos antiguos a través del estudio mediante MEB del desgaste, señalamos la importancia de disponer de un amplio programa experimental, y proponemos un modelo interpretativo según el cual dicho desgaste se explica por fenómenos básicamente atricionales, en los cuales la deformación plástica de los materiales líticos está plenamente contemplada. En cuanto a los resultados arqueológicos, se han identificado básicamente actividades relacionadas con la carnicería, pero también el tratamiento de la piel y acciones sobre materias vegetales. Los datos obtenidos han permitido avanzar en la interpretación de las ocupaciones humanas que generaron el registro de cada yacimiento estudiado, así como explicar parte de la variabilidad técnica presente en los conjuntos de modo 2, en función de las características del enclave donde se localiza el yacimiento (aire libre, abrigo o cueva), de la inmediatez de los recursos líticos y alimentarios, de las actividades llevadas a cabo y de la planificación técnica reflejada en el registro arqueológico. Concluimos la tesis proponiendo futuras líneas de investigación relacionadas con el análisis funcional de instrumentos de piedra, como son el avance en el modelo interpretativo de la deformación de materiales líticos (mediante la realización de experimentos que permitan cuantificar satisfactoriamente los procesos observados), el tratamiento estadístico de las variables consideradas esenciales, y el planteamiento de protocolos de estudio donde se combinen el análisis del desgaste con el de residuos. / The doctoral dissertation entitled Variability and Functional Patterns in Mode 2 Technical Systems. Use-wear Analysis in Lithic Assemblages of Grotta Paglicci's Riparo Esterno (Rignano Garganico, Foggia ), Áridos ( Arganda, Madrid ) and Galería-TN (Sierra de Atapuerca, Burgos ) focuses on the functional aspects of lithic artefacts, and how these can provide information about technical variability within Acheulean assemblages. The work is divided into two main parts. The first one is dedicated to methodological issues, including: 1) an introduction to the theoretical framework used (the Logic-Analytic System), 2) the methodological principles of functional studies with special emphasis on the use of Scanning Electron Microscopy (SEM), 3) an explanation of the principles underlying our experimental project, and 4) a revision of the main current issues in the field of use-wear analysis (i.e. the principal aspects relative to the interpretation of use-wear traces on archeological artifacts). The rest of this first part of the dissertation comprises a comprehensive presentation of the experimentation accomplished and the results obtained, finishing with a proposal for an interpretive model to explain wear processes on lithic artifacts. In the second part, we present the Acheulean sites studied: Riparo Esterno at Grotta Paglicci, the two Áridos sites, and Galería-TN. Each chapter includes a general description of the archaeological deposits and their associated lithic assemblages, a discussion of the functional results obtained, and the case-specific conclusions derived. Before the general conclusions, we include a general discussion chapter, where the results of our functional analysis are evaluated, confirming the viability of this kind of study, comparing the results obtained in each case study, and showing how these data may contribute to the debated issue on Acheulean technical variability. First in the general conclusions, we summarize the main methodological achievements of our research. We confirm the possibility to recognize actions and activities carried out with ancient artifacts through use-wear analysis using SEM. We also stress the importance of having a broad experimental program, and propose an interpretive model in which the aforementioned use-wear is basically explained according to attritional phenomena, including plastic deformation of lithic materials. In regards to the archeological results derived from this work, we have identified butchery activities, hide working and intervention on plant matter. The data obtained have enabled us to advance in the interpretation of the human occupations that generated the archaeological record of each of the sites studied. We also were able to explain some aspects of the technical variability among Mode 2 assemblages, in terms of the environmental conditions of each specific site (open air, rock shelter or cave), the availability of lithic and food resources, the kind of activities performed, and the technical planning deduced from the archeological record. In the final part of this work we propose several future lines of research related with stone tool functionality, such as: 1) the advancement of the interpretative model to explain the processes of deformation of lithic materials (through experiments that enable us to efficiently quantify the observed processes), 2) the statistical treatment of essential variables, and 3) a proposal of research protocols that combine use-wear analysis with residue studies.
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Stereotactict body radiotherapy (SBRT)Cecconi, Agnese <1979> 03 May 2012 (has links)
Purpose: evaluation and comparison of volumetric modulated RapidarcTM radiotherapy (RA-IMRT) vs linac based Stereotactic body radiotherapy (SBRT) in the salvage treatment of isolated lymph node recurrences in patients affected by gynaecological cancer.
Materials and Methods From January 2010 to September 2011, 15 patients affected by isolated lymph nodes recurrence of gynaecological cancer underwent salvage radiotherapy after conventional imaging staging with CT and 18-FDG-PET/CT. Two different radiotherapy techniques were used in this study: RA-IMRT (RapidarcTM implemented radiotherapy Varian Medical System, Palo Alto, CA, USA) or SBRT (BrainLAB, Feldkirchen, Germany).
Five patients underwent CT scan and all patients underwent 18FDG-PET/CT for pre-treatment evaluation and staging.
The mean total dose delivered was 54.3 Gy (range 50-60 Gy with conventional fractionation and 27.4 Gy (range 12-40 Gy hypofractionation) for RA-IMRT and SBRT respectively.
The mean number of fractions was 27.6 fractions (range 25-31) and 3-4 fractions , the mean overall treatment duration was 40.5 days (range 36-45) and 6.5 days (range 5-8 days) for RA-IMRT and SBRT respectively.
Results:
At the time of the analysis, October 2011, the overall survival was 92.3 % (80% for RA-IMRT and 100% for SBRT). Six patients are alive with no evidence of disease and also six patients are alive with clinically evident disease in other sites (40% and 50% patients RA-IMRT vs SBRT respectively, one patient died for systemic progression of disease and two patient were not evaluable at this time.
Conclusions: Our preliminary results showed that, the use of RA-IMRT and SBRT are an excellent local therapy for isolated lymph nodes recurrences of gynaecological cancer with a good toxicity profile and local control rate, even if any long term survivors would be expected. New treatment modalities like Cyberknife are also being implemented.
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Högstadiets fysiklektioner och ”en dator per elev” : Vilken potential ser lärare och hur upplever de den?Adam, David January 2019 (has links)
Svenska grundskolan närmar sig en tid när alla elever har egna datorer. Vissa lärare har arbetat med detta i många år och andra bara några. Frågan som undersöks i denna uppsats är vilken potential fysiklärare ser i denna utveckling och hur de upplever potentialen. Sju naturvetenskapslärare från Sydsverige intervjuades på ett semistrukturerat sätt och data analyserades med en fenomenografisk ansats. Resultatet visar att den potential som lärare beskriver kan kategoriseras som skapande, innehåll och interaktion men att det finns störningar som påverkar alla kategorier. Analys av hur lärare upplever potentialen belyses med följande kategorier; noggrannhet, effektivitet, flexibilitet och illustrativ. Uppsatsen försöker att undersöka både de negativa och positiva aspekterna inom dessa kategorier. Vidare forskning som undersöker hur elever upplever dessa kategorier av potential skulle kunna bidra till en bättre helhetsbild.
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Utlokalisering av montering till lågkostnadsländer : en fallstudie om Tetra Paks etablering i BrasilienBloch, Patrik, Daboczi, Peter January 2005 (has links)
<p>Preface: Establishing assembly and production facilities has traditionally constituted the possibility for companies to avoid high import duties, or a possibility to establish themselves in free-trade areas.</p><p>Purpose statement: This thesis is intended for companies that explore their possibilities to establish an assembly plant in Brazil. The aim is to try to interpret and to create an understanding concerning which factors can have an influence when relocating production activities abroad.</p><p>Research method: The basis for this study has been internal information from Tetra Pak along with literature. The study has been carried out as case study based research where interviews and articles have formed the basis for the gathering of data.</p><p>Results: For companies that want to establish long-term production, Brazil possesses the prerequisites required. However, not all areas in Brazil are adequate for establishing an assembly plant – industries are mainly concentrated to the federal states of São Paulo and Rio de Janeiro and these are therefore the areas best suited for production activities.</p>
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Med nya ögon mot stormen : Krisberedskap, ansvar och lärande ur ett medborgarperspektiv.Svensson, Mattias January 2009 (has links)
<p>The aim of this essay is, due to a noted lack of earlier research together with an even more accentuated responsibility regarding the matter in question, to study the citizens’ preparedness for crisis. Starting out from a number of questions regarding the citizens’ responsibility and</p><p>learning from the hurricanes Gudrun and Per, the discussion concerns the terminology of</p><p>crisis together with the question of responsibility and learning from experience.</p><p>In conclusion, the source material consisting of nine interviews shows that preparedness for crisis for the affected citizen above all is related to the personal measures to create a working situation in a state of crisis. Hence, to a great extent, the citizens show consciousness</p><p>of their own responsibility. Regarding the question of learning from these specific crises, this can only be noted among those citizens that lack earlier experience from crisis.</p>
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Livsfarlig ledning?Lundgren, Sofia January 2006 (has links)
No description available.
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Comparing Obesity Trends in Rural Versus Urban Peru from 1991 to 2005Timar, Dana 06 November 2009 (has links)
Background: The changes in diet and physical activity in populations over time has been described as the nutrition transition. It is currently thought that many developing nations are in a transition from the receding famine to the degenerative disease profile as these nations adopt “western diets” and the people become more sedentary. The literature has shown a unique relationship between Gross National Income (GNI) per capita and obesity. At or above a GNI per capita of $2500 (US), prevalence of obesity increase among lower socioeconomic status (SES) groups and falls in upper SES groups. Methods: To examine this transition in one country, data were analyzed from Peru. The data were obtained from the United States Agency for International Development’s Demographic Health Surveys administered from 1991 to 2008. During this time Peru’s GNI per capita increased from $1090 to $3990. For the analysis, all non pregnant women aged 15 to 49 who had body mass index (BMI) measurements taken during the survey were included. Prevalence ratios of underweight, normal weight, overweight, and obesity were compared for place of residence (urban or rural) and educational attainment for all four surveys completed during those years (1991-2, 1996, 2000, and 2004-5). Food consumption patterns in children from the same household were examined for surveys completed in 2000 and 2004. Results and Discussion: Over the survey period (1991-2005), average BMI measurements and obesity prevalence increased in all women in Peru from 8-12%. However, both average BMI and prevalence of obesity increased more rapidly in rural women. In terms of educational attainment, a proxy for SES, obesity was highest among urban women with higher educational attainment initially. However, it increased among other educational attainment groups over time. For rural women, obesity was highest among those with lower educational attainment over time. The consumption of oils, fats, and butters increased from 2000 to 2004 in both urban and rural children with the greatest increase among rural children. Based on the results, it appears that there is evidence of increased prevalence of obesity in rural compared to urban women in Peru from 1991-2005 suggestive of the nutrition transition from receding famine to degenerative disease. The more rapid increase in both BMI and obesity in rural women may be the result of increased access to different food products such as oils, fats and butters and increased consumption in rural areas. More research should be done to further clarify factors affecting this transition and the public health community and the government should examine and attempt to prevent further increase in obesity in Peru.
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