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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.
261

Biochar in perennial crops: nutritional, agronomical and environmental implications

Sorrenti, Giovambattista <1974> 18 May 2015 (has links)
Biochar is the solid C-rich matrix obtained by pyrolysis of biomasses, currently promoted as a soil amendment with the aim to offset anthropogenic C emissions, while ameliorating soil properties and growth conditions. Benefits from biochar seem promising, although scientific understandings are beginning to be explored. In this project, I performed a suite of experiments in controlled and in field conditions with the aims to investigate the effect of biochar on: a) the interaction with minerals; b) Fe nutrition in kiwifruit; c) soil leaching, soil fertility, soil CO2 emissions partitioning, soil bacterial profile and key gene expression of soil nitrification-involved bacteria; d) plant growth, nutritional status, yield, fruit quality and e) its physical-chemical changes as affected by long-term environmental exposure. Biochar released K, P and Mg but retained Fe, Mn, Cu and Zn on its surface which in turn hindered Fe nutrition of kiwifruit trees. A redox reaction on the biochar surface exposed to a Fe source was elucidated. Biochar reduced the amount of leached NH4+-N but increased that of Hg, K, P, Mo, Se and Sn. Furthermore, biochar synergistically interacted with compost increasing soil field capacity, fertility, leaching of DOC, TDN and RSOC, suggesting a priming effect. However, in field conditions, biochar did not affect yield, nutritional status and fruit quality. Actinomadura flavalba, Saccharomonospora viridis, Thermosporomyces composti and Enterobacter spp. were peculiar of the soil amended with biochar plus compost which exhibited the highest band richness and promoted gene expression levels of Nitrosomonas spp., Nitrobacter spp. and enzymatic-related activity. Environmental exposure reduced C, K, pH and water infiltration of biochar which instead resulted in a higher O, Si, N, Na, Al, Ca, Mn and Fe at%. Oxidation occurred on the aged biochar surface, it decreased progressively with depth and induced the development of O-containing functional groups, up to 75nm depth.
262

Entrepreneurship influential factors in development of rural tourism as diversified rural activity in Republic of Macedonia

Todorov, Kiril <1978> 12 June 2015 (has links)
Rural tourism is relatively new product in the process of diversification of the rural economy in Republic of Macedonia. This study used desk research and life story interviews of rural tourism entrepreneurs as qualitative research method to identify prevalent success influential factors. Further quantitative analysis was applied in order to measure the strength of influence of identified success factors. The primary data for the quantitative research was gathered using telephone questionnaire composed of 37 questions with 5-points Likert scale. The data was analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) by SmartPLS 3.1.6. Results indicated that human capital, social capital, entrepreneurial personality and external business environment are predominant influential success factors. However, human capital has non-significant direct effect on success (p 0.493) nonetheless the effect was indirect with high level of partial mediation through entrepreneurial personality as mediator (VAF 73%). Personality of the entrepreneur, social capital and business environment have direct positive affect on entrepreneurial success (p 0.001, 0.003 and 0.045 respectably). Personality also mediates the positive effect of social capital on entrepreneurial success (VAF 28%). Opposite to the theory the data showed no interaction between social and human capital on the entrepreneurial success. This research suggests that rural tourism accommodation entrepreneurs could be more successful if there is increased support in development of social capital in form of conservation of cultural heritage and natural attractions. Priority should be finding the form to encourage and support the establishment of formal and informal associations of entrepreneurs in order to improve the conditions for management and marketing of the sector. Special support of family businesses in the early stages of the operation would have a particularly positive impact on the success of rural tourism. Local infrastructure, access to financial instruments, destination marketing and entrepreneurial personality have positive effect on success.
263

Starch distribution in pear tree organs in relation to training systems, rootstocks and fruit quality

Mesa Juliani, Karen <1982> 18 May 2015 (has links)
Starch is the main form in which plants store carbohydrates reserves, both in terms of amounts and distribution among different plant species. Carbohydrates are direct products of photosynthetic activity, and it is well know that yield efficiency and production are directly correlated to the amount of carbohydrates synthesized and how these are distributed among vegetative and reproductive organs. Nowadays, in pear trees, due to the modernization of orchards, through the introduction of new rootstocks and the development of new training systems, the understanding and the development of new approaches regarding the distribution and storage of carbohydrates, are required. The objective of this research work was to study the behavior of carbohydrate reserves, mainly starch, in different pear tree organs and tissues: i.e., fruits, leaves, woody organs, roots and flower buds, at different physiological stages during the season. Starch in fruit is accumulated at early stages, and reached a maximum concentration during the middle phase of fruit development; after that, its degradation begins with a rise in soluble carbohydrates. Moreover, relationships between fruit starch degradation and different fruit traits, soluble sugars and organic acids were established. In woody organs and roots, an interconversion between starch and soluble carbohydrates was observed during the dormancy period that confirms its main function in supporting the growth and development of new tissues during the following spring. Factors as training systems, rootstocks, types of bearing wood, and their position on the canopy, influenced the concentrations of starch and soluble carbohydrates at different sampling dates. Also, environmental conditions and cultural practices must be considered to better explain these results. Thus, a deeper understanding of the dynamics of carbohydrates reserves within the plant could provide relevant information to improve several management practices to increase crop yield efficiency.
264

Dallo spreco alimentare alla creazione di capitale sociale. Definizione di strumenti metodologici per la valutazione dell'impatto sociale dei progetti di recupero alimentare / From food waste to social capital. Methodological tools for the assesment of social impact of projects of food recovery

Bellettato, Cecilia <1984> 12 June 2015 (has links)
Ogni anno in Europa milioni di tonnellate di cibo vengono gettate via. Una stima pubblicata dalla Commissione europea afferma che, nei 27 Stati membri, 89 milioni di tonnellate di cibo, o di 179 kg pro capite, vengono scartati. Lo spreco si verifica lungo tutta la catena di agro alimentare; la riduzione dei rifiuti alimentari è diventata una delle priorità dell'agenda europea. La ricerca si concentra su un caso studio, Last Minute Market, un progetto di recupero di sprechi alimentari. L'impatto di questo progetto dal punto di vista economico e ambientale è già stato calcolato. Quello che verrà analizzato è l'impatto di questa iniziativa sulla comunità e in particolare sul capitale sociale, definito come "l'insieme di norme e reti che consentono l'azione collettiva". Obiettivo del presente lavoro è, quindi, quello di eseguire, attraverso la somministrazione di un questionario a diversi stakeholder del progetto, un’analisi confrontabile con quella del 2009 e di verificare a distanza di cinque anni, se l'iniziativa Last Minute Market abbia prodotto una crescita di capitale sociale nella comunità interessata da questa iniziativa. Per riassumere l’influenza del progetto sul capitale sociale in un indice sintetico, viene calcolato quello che verrà chiamato indice di "affidabilità del progetto" (definito in statistica, la "capacità di un prodotto, un sistema o un servizio di fornire le prestazioni richieste, per un certo periodo di tempo in condizioni predeterminate"). / Every year in Europe million tons of food are thrown away. An estimation published by the European Commission states that, in the 27 Member States, 89 million tons of food, or 179 kg per capita, are discarded. Waste occurs all along food supply chain; reducing food waste has thus become one of the priorities on the European agenda. The research focuses on a case study, Last Minute Market, a project of recovery of food waste. The impact of this project from an economical and environmental point of view has already been calculated. What is going to be analyzed is the impact of this initiative on the community and specifically on social capital, defined as "the set of norms and networks that enable collective action". The objective of the work is to carry out an analysis on social capital dimensions through interviews to the different stakeholders involved in Last Minute Market project. The results of the analysis will be compared to the results of an analysis made in 2009 on the same project in order to check if it has produced a growth on social capital dimensions. Than, in order to summarize the influence of the project on social capital in a synthetic index, is calculated what we can called the index of “reliability of the project” (defined in statistics, the “ability of a product, a system or a service to provide the performance required, for a certain period of time under predetermined conditions”).
265

Identification of CNV and QTL for productive and functional traits in dairy cattle using dense SNP chips

Bagnato, Alessandro <1961> 16 April 2015 (has links)
The thesis identify CNV structural variants as possible markers for genomic selection and identify QTL regions for Fatty Acid Content in the Italian Brown Swiss population. Additionally it maps the QTL for mastitis resistance in the Valdostana Red Pied cattle.
266

From fossil to sustainable diets: an assessment of farming energy footprint

Pagani, Marco <1960> 12 June 2015 (has links)
The dependence of industrial agricolture on fossil fuels has been assessed in two comparative case studies between Italy (Emilia-Romagna and Piemonte)and Missouri. The first is related to dairy farming; 15 different farms were surveyed, divided into three different groups: grain based, pasture based and organic. The second is devoted to rice cropping; 12 holdings were examined divided into two groups: conventional and organic. Energy footprint was determined for structures, machinery, fertilizers, pesticides, fuel, electricity, feed and seeds. Possible scenarios of transition to a more sustainable agricolture based on renewable energy sources were analized in detail for all the farms analized.
267

La distribuzione del potere tra le Istituzioni Europee e la procedura di co-decisione. Il caso della riforma della Politica Agricola Comune / The distribution of power between the European Institutions and the codecision procedure. The case of the Common Agricultural Policy reform

Mihai, Roxana Dona <1981> 12 June 2015 (has links)
Questa ricerca analizza le implicazioni derivanti dall’introduzione della procedura di co-decisione come procedura legislativa ordinaria nel processo di riforma della politica agricola comune. La diversa distribuzione dei poteri tra le istituzioni europee modifica gli assetti istituzionali e fornisce al Parlamento il ruolo di colegislatore in materia agricola. La forma assunta dalla nuova politica agricola europea scaturisce dalla configurazione dei poteri di contrattazione che ciascun attore ha mostrato nella sede dei triloghi negoziali. La ricerca tenta di verificare la accuratezza predittiva di diversi modelli di contrattazione legislativa attraverso il confronto e la verifica degli errori di predizione sui risultati finali di alcune questioni salienti della riforma della Politica Agricola Comune e allo stesso tempo, cerca di identificare il peso del potere del Parlamento europeo in veste di co-legislatore nel processo di riforma della PAC post-2013. / This research analyzes the implications of the introduction of the codecision procedure as the ordinary legislative procedure in the process Common Agricultural Policy reform. The different distribution of powers between the European institutions modified the institutional structure and give to the European Parliament the role of colegislator in agricultural matters. The form taken by the new European agricultural policy derives from the configuration of the bargaining power that each actor has shown in the seat of the trialogue negotiations. The research attempts to verify the predictive accuracy of different models of legislative bargaining through the comparison and verification of prediction errors on the final results of some salient issues emerged during the Common Agricultural Policy reform process, and at the same time, try to identify the weight of the power of European Parliament as colegislator in the of CAP reform process post-2013.
268

Strumenti di prevenzione e riduzione degli sprechi alimentari. Un piano nazionale per l'Italia / Food waste prevention. A national plan for Italy

Azzurro, Paolo <1971> 12 June 2015 (has links)
Negli ultimi anni lo spreco alimentare ha assunto un’importanza crescente nel dibattito internazionale, politico ed accademico, nel contesto delle tematiche sulla sostenibilità dei modelli di produzione e consumo, sull’uso efficiente delle risorse e la gestione dei rifiuti. Nei prossimi anni gli Stati Membri dell’Unione Europea saranno chiamati ad adottare specifiche strategie di prevenzione degli sprechi alimentari all’interno di una cornice di riferimento comune. Tale cornice è quella che si va delineando nel corso del progetto Europeo di ricerca “FUSIONS” (7FP) che, nel 2014, ha elaborato un framework di riferimento per la definizione di “food waste” allo scopo di armonizzare le diverse metodologie di quantificazione adottate dai paesi membri. In questo scenario, ai fini della predisposizione di un Piano Nazionale di Prevenzione degli Sprechi Alimentari per l’Italia, il presente lavoro applica per la prima volta il “definitional framework” FUSIONS per l’analisi dei dati e l’identificazione dei principali flussi nei diversi anelli della filiera e svolge un estesa consultazione degli stakeholder (e della letteratura) per identificare le possibili misure di prevenzione e le priorità di azione. I risultati ottenuti evedenziano (tra le altre cose) la necessità di predisporre e promuovere a livello nazionale l’adozione di misure uniformi di quantificazione e reporting; l’importanza del coinvolgimento degli stakeholder nel contesto di una campagna nazionale di prevenzione degli sprechi alimentari; l’esigenza di garantire una adeguata copertura economica per le attività di pianificazione e implementazione delle misure di prevenzione da parte degli enti locali e di un coordinamento a livello nazionale della programmazione regionale; la necessità di una armonizzazione/semplificazione del quadro di riferimento normativo (fiscale, igienico-sanitario, procedurale) che disciplina la donazione delle eccedenze alimentari; l’urgenza di approfondire il fenomeno degli sprechi alimentari attraverso la realizzazione di studi di settore negli stadi a valle della filiera. / In recent years, food waste prevention is assuming a pivotal role within international, European and national strategies addressing waste prevention, resource efficiency and sustainability of production and consumption patterns. In the coming years the European Union Member States will be asked to adopt specific strategies to prevent food waste within a common reference framework. This framework is being developed within the “FUSIONS” research project (7FP) which, in 2014, released the “FUSIONS definitional framework for food waste”. The main aim of the FUSIONS’s framework is to provide Member States with a common definition to be used as a reference point in National strategies targeting food waste reduction. In this scenario, this study applies for the first time the "FUSIONS definitional framework" to identify and quantify the main streams generated along the food supply chain and to identify, with the support of an extensive stakeholder’s consultation, the priorities for action in the view of developing a National Plan for Food Waste Prevention in Italy. The results highlight (among others) the following priorities: to define and adopt at national level common quantification and reporting methodologies for food waste streams; to engage stakeholders within the framework of a national food waste prevention campaign; to set a national coordination for planning and financing regional intervention on food waste prevention; to harmonise and simplify the regulatory framework relating to food donation; to improve knowledge on food waste generated along the supply chain by strengthening the research activities.
269

Miglioramento delle performance termiche e energetiche degli edifici rurali: valutazione del retrofit di locali per la conservazione del vino su casi studio / Improvement of thermal and energy performance of rural buildings: assessment of wine storage rooms retrofit on case studies

De Maria, Federica <1985> January 1900 (has links)
Il presente studio si colloca all’interno di una ricerca più ampia volta alla definizione di criteri progettuali finalizzati all’ottimizzazione delle prestazioni energetiche delle cantine di aziende vitivinicole, di dimensioni produttive medio - piccole. Nello specifico la ricerca riguarda la riqualificazione di fabbricati rurali esistenti di modeste dimensioni, da convertire a magazzini per la conservazione del vino in bottiglia. Lo studio si pone come obiettivo la definizione di criteri di analisi per la valutazione di interventi di retrofit di tali fabbricati, volto sia al miglioramento delle prestazioni energetiche dell’involucro edilizio, sia alla riduzione del fabbisogno energetico legato al funzionamento di eventuali impianti di controllo termico. La ricerca è stata condotta mediante l’utilizzo del software di simulazione termica Energy Plus, per ottenere i valori simulati di temperatura interna relativi ai diversi scenari migliorativi ipotizzati, e mediante la successiva definizione di indicatori che esplicitino l’influenza delle principali variabili progettuali sull’andamento delle temperature interne dei locali di conservazione e sul fabbisogno energetico del fabbricato necessario a garantire l’intervallo di temperatura di comfort del vino. Tra tutti gli interventi possibili per il miglioramento della prestazione energetica degli edifici, quelli analizzati in questo studio prevedono l’aggiunta di un isolamento a cappotto delle pareti esterne, l’isolamento della copertura e l’aggiunta di una struttura ombreggiante vegetale esterna. I risultati ottenuti danno una prima indicazione sugli interventi più efficaci in termini di miglioramento energetico e mettono in luce l’utilità del criterio proposto nell’evidenziare le criticità degli interventi migliorativi ipotizzati. Il metodo definito nella presente ricerca risulta quindi un valido strumento di valutazione a supporto della progettazione degli interventi di retrofit dei fabbricati rurali da convertire a magazzini per la conservazione del vino. / This study is part of a broader research that aims to define design criteria to optimize energy performances of wineries in small-medium wine-growing and producing farms. Specifically, the research involves the renovation of small existing farm buildings, to be converted into warehouses for wine bottles storage. The study aims to define analysis criteria for the building retrofit assessment aimed at the evaluation of the building envelope energy performance for unconditioned buildings and of the reduction of thermal control system energy demand for conditioned buildings. The hypothesized retrofit interventions consist in the addition of thermal insulation applied on the external walls, roof insulation and external vegetable shading structure. These interventions are evaluated separately and combined. The study was carried out by means of the energy simulation program EnergyPlus. For each scenario EnergyPlus provided, as output, building indoor temperatures allowing the definition of indicators based on the thermal comfort for the wine. The indicators showed the influence of the considered intervention on the indoor temperatures or on the building’s energy demand. The results give first indications on the most effective retrofit intervention in terms of energy efficiency and underline the usefulness of the proposed criterion to highlight retrofits’ critical issues. The method defined in this research is therefore a valuable assessment tool to support retrofit’s design of farm buildings to be converted into wine-aging room.
270

Enhancing Resource Management in Socio-Ecological Systems: Modeling Collective Conditionality in Rural Policies

Zavalloni, Matteo <1983> 12 May 2016 (has links)
The collective approach toward natural resource management in agriculture is increasingly gaining attention, by both the literature and policy makers. In the thesis I analyse the implementation of collective approaches in rural policies aimed at natural resource management. More specifically, I analyse how two design elements of this type of policies, collective conditionality constraints and subsidy levels, affect the 1) emergence of cooperation among farmers and 2) the distribution of the benefits. In the analyses I address the effect of these policies in a range of situations, namely in case the action subsidized by policy is a public good, a club good, or only a private cost (and thus cooperation is purely linked to the implementation of the policy). The distributional effect is addressed only in the club good case. The results show that indeed the proper use of collective conditionality constraints associated to subsidies can improve the cooperation of farmers and thus leading to more effective agri-environmental policies. It seems that the collective approach for natural resource management is a strategy that deserves higher attention and policy effort. However, it should not be taken lightly or naively implemented, as the "sophistication" of mechanisms also increases the scope for unexpected policy outcomes. A more aware implementation of such strategy also requires a greater, inter-disciplinary, effort for research, towards a proper understanding of actual effects of real life policy options and coordination mechanisms.

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