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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.
81

[en] ASSESSMENT OF FACTORS AND COLLABORATIVE STRATEGIES THAT IMPACT FOREST RESTORATIONS CHAINS IN ATLANTIC RAINFOREST PRIVATE LANDS / [pt] AVALIAÇÃO DOS FATORES E ESTRATÉGIAS COLABORATIVAS QUE IMPACTAM CADEIAS DE RESTAURAÇÃO FLORESTAL EM ÁREAS PRIVADAS NA MATA ATLÂNTICA

FERNANDA RESENDE DE SOUZA CARDOSO 11 February 2021 (has links)
[pt] O Brasil assumiu no Acordo de Paris a meta de restaurar 12 milhões de hectares de florestas até 2030, dos quais 5 milhões devem ocorrer na Mata Atlântica. Porém, a maior parte da área remanescente das florestas está localizada em áreas privadas e há uma série de fatores que dificultam a efetivação da restauração por parte dos proprietários. O objetivo dessa pesquisa foi identificar e avaliar as estratégias colaborativas que são utilizadas pelos principais participantes da cadeia de restauração florestal na Mata Atlântica do estado do Rio de Janeiro, de modo a superar barreiras, aproveitar oportunidades para o sucesso desses projetos e atingir uma sustentabilidade econômica, ambiental e social na região. Para isso, foi realizada uma pesquisa descritiva, com abordagem qualitativa, a partir de entrevistas em profundidade com especialistas e participantes dessa cadeia e de dados coletados em documentos e sites de projetos de restauração. Algumas das principais barreiras encontradas são: dificuldades logísticas na cadeia; escassez de mão-de-obra qualificada; baixa demanda por projetos de restauração; falta de implementação da legislação; dificuldade de integração de esforços privados e públicos; comunicação deficiente entre atores locais; retrocessos na compreensão da importância da conservação da biodiversidade. Foram identificadas algumas estratégias colaborativas usadas (cooperativas, redes formais e informais, participação em Conselhos) e avaliadas sua efetividade. Ao final foram feitas recomendações para o aprimoramento das estratégias atuais e para a adoção de novas estratégias colaborativas a fim de contribuir, junto a outras iniciativas de caráter econômico e regulatório, para a superação das barreiras. / [en] Brazil assumed in The Paris Agreement the commitment of 12 million hectares of forests restored by 2030, of which 5 million will occur in the Atlantic Rainforest. However, most of the remaining forest areas are located in private lands and there are a number of factors that difficult the adoption of restoration by landowners. The objective of this research was to identify and evaluate the collaborative strategies that used by the main participants of the forest restoration chains in the Atlantic Rainforest in the State of Rio de Janeiro, with the purpose to overcome barriers, take advantage of successful opportunities of these projects and achieve the region s economic, environmental and social sustainability. A descriptive research was carried out with a qualitative approach, based on in-depth interviews with specialists and chains participants and data collected in documents and restoration projects websites. The main barriers encountered include: logistical difficulties in the network; lack of qualified labor; low demand for restoration projects; lack of implementation of legislation; difficulties in integrating private and public efforts; poor communication between local actors; discussion setbacks related to the importance of biodiversity conservation. The most important collaborative strategies were identified (cooperatives, formal and informal networks, participation in Councils) and their effectiveness assessed. Recommendations were made to improve current strategies and adopt new collaborative strategies in order to contribute, with other economic and regulatory initiatives, to overcoming barriers.
82

I rapporti euro-atlantici dopo l'undici settembre 2001: correnti politico-intellettuali negli Stati Uniti / The Transatlantic Relationship after 9/11: Political Ideas and Movements in the United States

GARIBALDI, IDA MARINA ELISABETTA SELVAGGIA 11 September 2008 (has links)
Questo lavoro analizza le relazioni tra Stati Uniti ed alleati europei dal 1989 ad oggi, con particolare approfondimento del periodo successivo all'undici settembre 2001. L'ipotesi di ricerca è basata sulla convinzione che gli attentati del 2001 abbiano avuto un impatto fondamentale sulla relazione euro-atlantica, accelerando tendenze centrifughe già presenti nel rapporto. La tesi è composta da un'analisi storica, da sette capitoli e dalle conclusioni. L'analisi storica esamina i cambiamenti strutturali nella relazione transatlantica dopo il 1989. I capitoli 1 e 2 presentano le correnti politiche determinanti nel formulare la politica estera americana dopo il 2001, con particolare riferimento al movimento neoconservatore. I capitoli 3 e 4 analizzano la definizione di impero moderno , la questione se gli Stati Uniti siano o meno un impero e la possibilità che l'Unione europea (UE) diventi una superpotenza. I capitoli 5, 6 e 7 approfondiscono tre nodi gordiani : il futuro della NATO; la Russia tra Stati Uniti e UE; e la relazione triangolare tra Stati Uniti, Cina e UE. Infine, le conclusioni riassumono le debolezze del rapporto tra Stati Uniti ed alleati europei, evidenziano come esse siano peggiorate dopo gli attentati del 2001 e presentano i pericoli in cui la relazione potrebbe incorrere in futuro. / This dissertation studies the relationship between the United States and its European allies from the end of the Cold War to the present, with a focus on the period following the terror attacks on September 11, 2001. The primary conclusion is that 9/11 accelerated divisive trends within transatlantic alliance. The dissertation has an historical introduction, seven chapters and the conclusions. The historical introduction analyzes the structural changes occurred within the transatlantic relationship after 1989. Chapters 1 and 2 discuss the political movements and ideas that shaped American foreign policy after 9/11, with a focus on the neoconservative movement. Chapters 3 and 4 define the idea of modern empire ; its use in reference to the United States; and the idea that the European Union is becoming a superpower able to counterbalance the United States. Chapters 5, 6 and 7 focus on three looming challenges within the transatlantic relationship: the future of NATO; relations with Russia; and the rise of China. The conclusions summarize the weaknesses of the relationship between the United States and its European allies; highlight how they deteriorated after 9/11; and describe the dangers that lay ahead for the transatlantic alliance.
83

LA "RELAZIONE SPECIALE" ANGLO-AMERICANA E LA GUERRA DELLA FALKLAND (1982) / The Anglo-American "special relationship" and the Falklands war (1982)

BORSANI, DAVIDE 31 March 2015 (has links)
Nell’aprile 1982, l’Argentina – un Paese alleato degli Stati Uniti attraverso il Patto di Rio – invase le isole Falkland, un Territorio d’Oltremare del Regno Unito, rivendicato da Buenos Aires sin dal XIX secolo. Margaret Thatcher, l’allora Primo Ministro britannico, rispose con vigore. Alla fine la Gran Bretagna – alleato NATO degli USA – riuscì a riconquistare le isole e a ristabilire lo status quo ante. Il conflitto va inquadrato nel framework della ‘seconda Guerra Fredda’. Il confronto tra gli Stati Uniti e l’Unione Sovietica fu particolarmente aspro nei primi anni Ottanta e la logica bipolare influenzò le dinamiche diplomatiche della guerra del 1982. Da un lato, l’Emisfero occidentale era al centro della rinnovata strategia americana anti-comunista e l’Argentina era il principale pilastro nel Cono Sud. Dall’altro lato, il rafforzamento della ‘speciale relazione’ anglo-americana costituiva la pietra angolare della grand strategy statunitense nel teatro europeo. Con questo sfondo, è naturale domandarsi quale ruolo Washington scelse di giocare nella guerra delle Falkland tra due dei suoi alleati. A causa di interessi divergenti, la ‘relazione speciale’ non fu infatti del tutto speciale. / In April 1982, Argentina – a country allied with the United States through the Rio Pact – suddenly invaded the Falkland Islands, a long-time Overseas Territory of the United Kingdom, disputed by Buenos Aires since the XIXth century. Margaret Thatcher, the then British Prime Minister, vigorously responded and finally Britain – a US NATO ally – was able to regain the Islands and re-establish the status quo ante. The conflict needs to be contextualized in the ‘second Cold War’ framework. The struggle between the United States and the Soviet Union was particularly tough in the first years of the 1980s and the bipolar logic strongly influenced the diplomatic course of the 1982 war. On the one hand, the Western hemisphere was at the core of the renewed anti-communist US strategy and Argentina was the main pillar in the Southern Cone. On the other hand, the strengthening of the Anglo-American ‘special relationship’ was the European cornerstone of the US grand strategy. Against this background, what kind of role the US chose to play in the Falklands war between two of their allies instinctively arises as the main question. Affected by diverging interests, the ‘special relationship’ was not indeed entirely special.
84

Contribution de la RMN 13C à l'analyse des huiles végétales, huiles essentielles et résines (Olea europaea, Pinus halepensis et Cedrus atlantica)

Nam, A.-M. 21 March 2014 (has links) (PDF)
Les produits issus de la biomasse végétale connaissent depuis quelques années un succès grandissant dans de nombreuses industries (aromathérapie, cosmétique, parfums, etc.). L'objectif de notre étude était, d'une part de contribuer au développement des méthodes d'identification et de quantification des constituants des mélanges naturels par RMN 13C et RMN 1H (par exemple le squalène dans l'huile d'olive), et d'autre part, de contribuer à la caractérisation chimique de deux conifères introduits en Corse, le pin d'Alep (huile essentielle) et le cèdre de l'Atlas (huile essentielle, huile pyrolytique et résine). La première partie concerne la quantification du squalène présent dans l'huile d'olive. En effet, ce triterpène linéaire participe à la stabilité oxydative de l'huile d'olive et joue un rôle important dans la réduction des risques de certains cancers. Il s'agissait de mettre au point un protocole expérimental basé sur la RMN 1H ou 13C en utilisant un appareil de routine (9,4 Tesla). La quantification par RMN 13C s'est avérée fiable et elle a été appliquée à la quantification du squalène dans 25 échantillons d'huile d'olive de Corse. La seconde partie de nos travaux concerne la caractérisation chimique de l'huile essentielle de pin d'Alep introduit dans trois stations de Corse (Capo di Feno, Saleccia et Tre Padule de Suartone). L'analyse détaillée de l'huile essentielle de cônes, par combinaison des techniques chromatographiques et spectroscopiques, a permis d'identifier 48 composés. La composition chimique est largement dominée par les monoterpènes (a-pinène et myrcène) et un sesquiterpène oléfinique ((E)-a-caryophyllène). La RMN 13C a permis d'identifier divers diterpènes, dont le 8,12-époxy-14-labdèn-13-ol. Ce composé est décrit pour la première fois dans l'huile essentielle de pin d'Alep. L'analyse de 15 échantillons d'huile essentielle de cônes a mis en évidence trois types de compositions : a-pinène ; myrcène ; a-pinène/myrcène. Enfin, l'analyse de 47 échantillons d'huile essentielle d'aiguilles, associée à un traitement statistique des données (ACP, AFD), a permis de mettre en évidence une variabilité chimique intraspécifique. Ainsi, les échantillons se répartissent en trois groupes selon leur teneur en (E)-a-caryophyllène (groupe I), en E-a-caryophyllène/a-pinène/myrcène (groupe II) et en myrcène (groupe III). La dernière partie a été consacrée à l'étude de Cedrus atlantica. L'analyse détaillée d'une huile essentielle commerciale (du Maroc) a permis d'identifier 20 constituants, les composés majoritaires sont les b-, a- et g-himachalène. Par ailleurs, 7 composés absents de notre bibliothèque de données spectrales ont été identifiés par RMN 13C. Les compositions chimiques des huiles pyrolytiques artisanales du Maroc sont également dominées par les himachalènes et la (E)-a-atlantone. Enfin, nous avons réalisé l'analyse qualitative et quantitative par RMN 13C, sans séparation préalable, de 28 échantillons de résine de C. atlantica récoltés dans les 5 forêts de Corse référencées par l'ONF (Bavella, Bonifato, Ospedale, Pineta et Vizzavona). A côté des acides résiniques, nous avons également identifié 3 lignanes (pinorésinol, laricirésinol et 9-acétate de laricirésinol). Pour l'ensemble de ces composés, nous avons mis en évidence trois types chimiques. Enfin, nous avons mis au point et validé un protocole expérimental de quantification des lignanes par RMN 1H. Discipline : Chimie organique et analytique Mots clés : Analyse des mélanges complexes naturels ; Huiles essentielles ; Huiles pyrolytiques ; Huiles d'olives ; Oléorésines ; RMN 13C ; RMN 1H ; Squalène ; Lignanes ; Olea europaea ; Pinus halepensis ; Cedrus atlantica

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