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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

Incentives for the Adoption of Socially Beneficial Technologies: The Case of an E. coli Vaccine

2015 January 1900 (has links)
Using the E. coli vaccine as a case study, this thesis examines the factors affecting the adoption of technologies with positive spillover (externality) effects related to food safety. Positive spillovers occur when the benefits from a technological innovation extend beyond the firm (farm) adopting the technology or they do not flow to the adopter. If there are insufficient incentives for the firm to adopt the new technology, adoption levels are sub-optimal, resulting in forgone benefits to society. These benefits include the avoidance of potential health costs, productivity loss and premature death costs as a result to exposure to E. coli O157:H7. Therefore, if the market incentives to adopt the technology are strengthened, adoption levels of the technology could reach socially optimal levels resulting in an improvement in food safety. This has been the case in the Canadian cattle industry, where the uptake of the E. coli vaccine by cow-calf producers has been very low. As such, a number of potential incentives to increase adoption of the vaccine were identified and assessed through a survey of cow-calf producers on the Prairies. Data from the survey were analyzed using a stated preference methodology, Best-Worst Scaling, and Latent Class cluster analysis. A Binary Probit Model was also used to examine the factors affecting willingness to adopt the vaccine. The results suggest that a significant number of producers were not aware of the existence of the E. coli vaccine. In addition, producers were most likely to be influenced in their adoption decisions by market/supply chain oriented incentives and government intervention incentives in the form of subsidies. On the other hand, incentives that were least likely to influence cow-calf producers’ decisions to adopt included government intervention through recommending use of vaccine and neighbours (other cow-calf producers) adopting the vaccine. The Latent Class cluster analysis revealed the existence of three unique producer clusters with different attitudes towards these incentives. Several socio-demographic variables and individual characteristics utilized in the Probit analysis were found to be determinants of a producer’s willingness to adopt an E. coli vaccine. The implications of this research are such that producer education and awareness campaigns may be utilized as tools for disseminating information on food safety technologies such as the E. coli vaccine. Furthermore, the market/supply chain incentives may be used to form potential market-based solutions to address the current low adoption rates. The existence of three unique producer clusters suggest that a one-size fits all strategy to encourage the adoption of the E. coli vaccine might be difficult to implement and thus a more targeted approach may be a feasible alternative.
82

Concentrações e fontes de silício foliar na produção e na qualidade do agrião e do almeirão / Concentrations and sources of silicon foliar in the production and quality of cress and chicory

Garcia Neto, Júlio 16 March 2018 (has links)
Submitted by JULIO GARCIA NETO (tec.juliogarcia@ifma.edu.br) on 2018-05-03T00:36:56Z No. of bitstreams: 1 Dissertacao_Julio_Garcia_Neto_2018.pdf: 913083 bytes, checksum: 5a833ab7fa1d0e34d10d5321c04c4640 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-05-04T17:23:54Z (GMT) No. of bitstreams: 1 garcianeto_j_me_jabo.pdf: 913083 bytes, checksum: 5a833ab7fa1d0e34d10d5321c04c4640 (MD5) / Made available in DSpace on 2018-05-04T17:23:54Z (GMT). No. of bitstreams: 1 garcianeto_j_me_jabo.pdf: 913083 bytes, checksum: 5a833ab7fa1d0e34d10d5321c04c4640 (MD5) Previous issue date: 2018-03-16 / A pulverização foliar de silício (Si) pode beneficiar a produção e a qualidade das hortaliças folhosas, sendo desconhecidos esses efeitos no agrião-da-terra (Barbarea verna) e no almeirão (Cichorium intybus cv. Spadona). Objetivou-se verificar o efeito da pulverização foliar de silício em diferentes fontes e concentrações no teor foliar de Si, nas variáveis de crescimento, no teor foliar de ascorbato e na perda de água durante o armazenamento das hortaliças agrião e almeirão. Foram realizados dois experimentos, com as duas hortaliças cultivadas em vasos (4 dm3) preenchidos com areia, recebendo solução nutritiva. Durante o cultivo, a média da temperatura máxima atingiu 43,1 °C ± 10,6 °C. Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 2 x 4, sendo duas fontes de silício: silicato de potássio e silicato de sódio e potássio estabilizado, e quatro concentrações de Si foliar: 0 (controle); 0,84; 1,68; 2,52 g L-1 de Si, com quatro repetições. As mudas foram transplantadas após 10 dias da emergência para vasos. Foram realizadas três aplicações foliares de Si, a cada dez dias, sendo a primeira realizada aos 28 dias após o transplantio (DAT). A pulverização foliar de silício é viável, para incrementar o acúmulo deste elemento na planta, o crescimento e a biofortificação, e diminui a perda de água da folha pós-colheita do agrião da terra e do almeirão, destacando-se a concentração de 2,52 g L-1 de Si na forma de silicato de potássio. / Silicon (Si) leaf spraying can benefit the production and quality of leafy vegetables. Such knowing is unclear to land cress (Barbarea verna) and root chicory (Cichorium intybus cv. Spadona). This study aimed was verify the effect of silicon leaf spraying under different sources and concentrations in Si leaf content, on growth variables, ascorbate leaf content, and water loss during storage of land cress and root chicory. We carried out two experiments with two vegetables grown in (4 dm3) pots filled with sand, receiving nutrient solution. During growing, the maximum temperature average was 43.1 °C ± 10.6 ºC. A completely randomized design was used in a 2 x 4 factorial scheme, with two sources of silicon: potassium silicate and stabilized sodium and potassium silicate, and four concentrations of leaf spraying Si: 0 (control), 0.84, 1.68, and 2.52 g L-1 of Si, with four replications. The seedlings were transplanted after 10 days of vessel emergence. Three Si leaf sprayings were done every ten days where the first spraying was at 28 days after transplanting (DAT). Silicon leaf spraying is feasible to increase the Si accumulation, plant growth and biofortification and decrease the post-harvest water loss of land cress and root chicory leaves. The Si concentration of 2.52 g L-1 as potassium silicate was highlighted.
83

Fontes e concentrações de silício foliar na produção e na qualidade da acelga e da couve / Silicon leaf fertilization concentration and sources in the production and quality of chard and kale

Souza, José Zenóbio de 16 March 2018 (has links)
Submitted by JOSÉ ZENÓBIO DE SOUZA (j.zenobio@ifma.edu.br) on 2018-05-03T20:36:15Z No. of bitstreams: 1 Dissertacao_Jose_Zenobio_Souza_2018.pdf: 1297284 bytes, checksum: 14b302d268235eca24061b9182a49edc (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-05-04T18:20:53Z (GMT) No. of bitstreams: 1 souza_jz_me_jabo.pdf: 1297284 bytes, checksum: 14b302d268235eca24061b9182a49edc (MD5) / Made available in DSpace on 2018-05-04T18:20:53Z (GMT). No. of bitstreams: 1 souza_jz_me_jabo.pdf: 1297284 bytes, checksum: 14b302d268235eca24061b9182a49edc (MD5) Previous issue date: 2018-03-16 / O silício (Si) é um elemento benéfico para as plantas que pode incrementar seu crescimento em condições de estresse e ainda refletir na qualidade, mas cujos efeitos não são conhecidos com a aplicação foliar do elemento na acelga e na couve, objetivou-se avaliar fontes e concentrações de Si via foliar na produção e na qualidade da acelga e da couve. Realizaram-se dois experimentos em casa de vegetação com acelga (Beta vulgaris var. cicla), cultivar verde-escura, e com couve (Brassica oleracea L var. acephala), cultivar manteiga-da-geórgia, em sistema de cultivo hidropônico, em vasos com areia contendo uma planta, cultivadas com a média da temperatura máxima de 43,1 °C ± 10,6 °C. Os experimentos foram conduzidos em delineamento inteiramente casualizados, com oito tratamentos e quatro repetições, em esquema fatorial 2 x 4, sendo duas fontes de Si, silicato de potássio (Si = 128 g L-1; K2O = 126,5 g L-1) e silicato de potássio e sódio estabilizado (Si = 115 g L-1; K2O = 19 g L-1), e quatro concentrações (0,00; 0,84; 1,68 e 2,52 g L-1) de Si. Realizaram-se três pulverizações foliares a cada 10 dias, iniciando aos 20 dias após o transplantio (DAT). As plantas de acelga e de couve foram colhidas aos 48 e 54 (DAT), respectivamente. Avaliaram-se a altura das plantas, a massa da matéria fresca, o teor de vitamina C (Ascorbato), a perda de água durante o armazenamento, massa da matéria seca, o teor e o acúmulo de Si nas folhas. A aplicação de Si foliar é viável para hortaliças folhosas de acelga e couve, pois incrementou o teor e o acúmulo do elemento, o crescimento, a produção, e melhorou a qualidade, inclusive a biofortificação, destacando-se a concentração de Si foliar de 2,52 g L-1 na forma de silicato de potássio. / Silicon (Si) is a beneficial element for plants. Its usage can increase plant growth under stressful conditions and still improve plant quality, but these effects are still unknown with foliar application of the element in chard and kale. This aim of this study was to evaluate sources and concentrations of Si leaf fertilization on the production and quality of chard and kale. Two experiments were carried out in a greenhouse with chard (Beta vulgaris var. cicla), “verde-escura” cultivar and kale (Brassica oleracea L var. acephala), “manteiga-da-geórgia” cultivar using a hydroponic culture system in pots filled with sand containing one plant each, grown under the mean maximum temperature of 43.1 °C ± 10.6 °C. The experiments were carried out under a completely randomized design with eight treatments and four replications in a 2 x 4 factorial scheme and two sources of silicon: potassium silicate (Si = 128 g L-1, K2O = 126.5 g L-1) and (Si = 115 g L-1, K2O = 19.0 g L-1) and four concentrations (0.00; 0.84; 1.68 and 2.52 g L-1). We performed three leaf sprays every 10 days, starting at 20 days after transplanting (DAT). The chard and kale plants were harvested at 48 and 54 (DAT), respectively. We evaluated plant height, fresh matter mass, vitamin C content (Ascorbate), water loss during storage, dry matter mass, Si content, and Si accumulation in the leaves. Si leaf fertilization is viable for leafy vegetables as chard and kale, because this fertilization increased the content and the accumulation of Si, growth, production, and also improved the quality, including the biofortification, where the Si leaf concentration of 2.52 g L-1 as potassium silicate was highlighted.
84

Déterminants biotiques d'une interaction durable lâche : interactions entre un microprédateur hématophage, son hôte oiseau et les communautés d'acariens du fumier / Biotic determinants of sustainable loose interaction : interactions between blood-sucking micro-predator, its host bird and manure mite communities.

El Adouzi, Marine 09 November 2017 (has links)
Le pou rouge Dermanyssus gallinae est un acarien d’importance sanitaire et économique majeure en élevage de poules pondeuses partout dans le monde mais paradoxalement le fonctionnement de son écosystème a été relativement peu étudié. Hématophage strict, D. gallinae n’est pas un parasite typique, il entretient une relation lâche mais obligatoire avec son hôte. Confiné dans l’environnement proche de son hôte (nids, fientes sèches, litière, fumier, . . .) D. gallinae est fortement soumis aux interactions avec les autres organismes qui peuplent ces microhabitats. Ce travail a pour objectif d’apporter des éléments pertinents de caractérisation de cet écosystème singulier mal connu pour, au delà de la production de connaissance, alimenter une réflexion sur le développement de stratégies de gestion intégrée innovantes afin de s’affranchir de la stricte lutte chimique qui reste à l’heure actuelle le moyen de luttele plus largement utilisé. L’étude des interactions chimiques entre le pou rouge et son hôte a permis de mieux identifier les sources de stimulus et mieux comprendre les réponses de D. gallinae aux odeurs de poule ainsi que de déterminer dans quelle mesure il était possible d’interférer entre l’hôte et son microprédateur au moment de l’étape de repérage. La caractérisation de la structure des communautés d’arthropodes partageant les mêmes microhabitats que le pou rouge a montré que D. gallinae côtoyait plusieurs espèces d’acariens et insectes prédateurs d’arthropodes qui sont potentiellement ses ennemis naturels. Il a également été mis en évidence que le bâtiment d’élevage constituait une unité propre en termes de composition et de structure des communautés d’arthropodes. Les différences significatives de fréquence et d’occurrencedes différentes espèces prédatrices entre bâtiments, ainsi que leur capacitéde propagation depuis l’environnement extérieur constituent des indicateurs prometteurs pour le développement de la lutte biologique par conservation contre le pou rouge. Des questions transversales quant aux effets croisés, synergiques ou antagonistes, entre la manipulation des odeurs de l’hôte et la mise à contribution des processus écologiques impliquant les arthropodes non hématophages sont posées en vue d’une démarche intégrant ces outils ainsi que les autres moyens de contrôle disponibles dans un contexte de protection biologique intégrée du pou rouge. / The Poultry Red Mite (PRM) Dermanyssus gallinae is a mite of major sanitary andeconomic importance for the egg production industry worldwide but paradoxicallythe functioning of its ecosystem has been little studied. The objective of this work was to provide relevant elements for the characterization of this singular ecosystem that is poorly known, in order to, beyond the production of knowledge, contribute to the development of innovative strategies of integrated management. This is expected to allow going further than the strict chemical control which is still to date the most widely used means of control. The study of the chemical interactions between the PRM and its host allowed to better identify sources of stimulus and to better understand D. gallinae’s responses to chicken odors as well as to determine to what extent it was possible to interfere between the host and its micropredator during the first phase of the host location. The characterization of the structure of arthropod communities sharing the same microhabitats as does PRM showed that D. gallinae was associated with several species of mites and predatory insects of arthropods which could potentially be its natural enemies. It was also demonstrated that the livestock building was a specific unit in terms of the composition and structure ofthe arthropod communities. Significant differences in the frequency and occurrence of predatory species between buildings and their propagation capacity from the external environment are promising indicators for the development of conservation biological control (CBC) against PRM. A reflection on the possible synergistic and antagonistic cross-effects between the manipulation of host odors and the stimulation of ecological processes involving non-haematophagous arthropods is carried out. This is expected to participate in the development of an approach integrating these tools as well as other available means of control in a context of integrated biological protection of PRM.
85

Effects of Host-plant Density on Herbivores and Their Parasitoids: A Field Experiment with a Native Perennial Legume

Salas, Andrea 07 July 2016 (has links)
Senna mexicana chapmanii (Fabaceae: Caesalpinoideae), an attractive and threatened species native to pine rocklands of southern Florida, is consumed by folivorous caterpillars of Sulfur butterflies (Lepidoptera: Pieridae). Caterpillars may be deterred or eaten by predators, but also very important are parasitoids, both flies and wasps. This study investigated the effects of plant density on Sulfur caterpillar numbers and rates of parasitization. Senna mexicana chapmanii plantations were established at agricultural and urban areas; both sites are adjacent to protected pine rockland areas. Sulfur butterfly immature stages were collected and reared to glean information regarding number of herbivores and rates of parasitization. Continuing this weekly monitoring protocol over the course of a year provided data to determine that higher plant density has an effect on levels of parisitization and is correlated with the number of herbivores. Elucidating these patterns has important implications understanding the factors that regulate interactions in this plant/herbivore/parasitoid system.
86

Zdanění dividend / Taxation of Dividends

Lodrová, Monika January 2015 (has links)
The thesis deals with taxation of dividend income that is being paid out from or to the Czech Republic. It gives an insight into the international tax regulations and their impact on the Czech legislation. The thesis focuses on the definition of dividends and relevant tax procedures. Furthermore, it makes an assessment based on practical scenarios, on the extent of tax burden of persons, Czech tax residents that receive dividends; and the impact on Czech tax revenues in connection with dividend payout to different countries.
87

Strategies to Improve Project Management Maturity Processes

Sargent, Walter H. 01 January 2016 (has links)
Information technology organizations lose significant competitive value when business leaders fail to use project management maturity (PMM) processes that enhance market delivery, reduce costs, and increase profitability. Using a multiple-case study, the researcher explored strategies that project leaders have used to improve PMM processes and expanded upon Kerzner's PMM model, which comprises 5 PMM levels essential for achieving repeatable project success. The researcher selected 20 project leader participants in the Southeastern region of the United States using a purposeful snowball sampling technique. In depth interviews were combined with archival and document exploration using a multiple-case study design where different types of project offices were cross compared as the unit of analysis including governmental, corporate, nonprofit, and not-for-profit organizations. Thematic analysis and cross-case analysis revealed 6 major strategies to improve PMM processes: project leader development, customer focus, standard methodology development, interactive communication, establishing a project office organizational structure, and practicing continuous process improvement. The implications for positive social change include the potential to provide small businesses and marginally-resourced organizations, such as churches and charitable organizations, with a beneficial value that contributes to positive economic activity in the local communities they support. The results are important because they extend constrained resources and organizational buying power for deliverables required by the recipient of the altruistic act.
88

Potential of Beneficial Trichoderma Isolates in Alleviating Water Deficit Stress in Tomato

Rawal, Ranjana January 2021 (has links)
No description available.
89

Multivariable analysis for studies of the origin of residual peroxide / Multidatanalys för studier av uppkomst av restperoxid

Johansson, Sara January 2022 (has links)
På pappersmaskin 11 i Hallsta pappersbruk tillverkas högglansigt papper som bleks med väteperoxid. Om väteperoxiden som finns kvar efter blekningen, kallat restperoxid, kommer ut på pappersmaskinen sliter detta på termovalsarna, vilket påverkar slutprodukten. Det finns en bakteriekultur på bruket, bestående av släktet Tepidiphilus som bryter ner väteperoxiden med hjälp av katalas och hindrar den från att komma ut på maskinen. Om bakterierna slås ut, av exempelvis ogynnsamma förhållanden, märks detta genom att restperoxiden ökar. Målet med detta arbete är att försöka identifiera vilka faktorer som påverkar bakterierna och lägga fram ett förslag för hur man kan förhindra uppkomsten av restperoxid. För att utföra detta användes i första hand principalkomponentanalys, samt så studerades hur olika faktorer förändrades i förhållanden till uppkomsten av restperoxid. Ett antal parametrar kunde identifieras baserat på tillgängliga data. Dock kan inga absoluta slutsatser dras då det inte går att bekräfta några teorier med labbförsök eller genom att manipulera processen. De parametrar som tros ha störst påverkan är mek. renat färg, rest-aluminium, grumlighet, manganhalten i vatten, pH för kar K0203, returmälden samt inloppslådan och klorhalterna som uppmätts för mek. renat total klor, RVV1 fri klor, varmvatten total klor och mek. renat fri klor. Dessa parametrar bör därför övervakas framåt, och kan i det fall att restperoxid återigen uppkommer antingen bekräftas eller dementeras deras faktiska påverkan och samspel för bakteriernas välmående. / Paper machine 11 in Hallsta paper mill produces high-gloss paper that is bleached with hydrogen peroxide. If the hydrogen peroxide that remains after the bleaching, called residual peroxide, gets out on the paper machine, this wears down the thermal rollers, which affects the final product.  There is a bacterial culture at the mill, consisting of the genus Tepidiphilus, which breaks down the hydrogen peroxide with the help of catalase and prevents it from getting out to the machine. If the bacteria are killed, for example by unfavourable conditions, this is noticeable by an increase in residual peroxide. The goal of this project is to try to identify which factors affect the bacteria and put forward a proposal for how to prevent the occurrence of residual peroxide. To carry this out, principal component analysis was primarily used, and how different factors changed in relation to the appearance of residual peroxide was studied. Several parameters could be identified based on the available data. However, no conclusive conclusions could be drawn as it is not possible to confirm any theories with lab tests or by manipulating the process. The parameters believed to have the greatest influence are coloration of mechanically cleaned water (mech. water), residual aluminium, turbidity, manganese content of the water, pH for tank K0203, the returning pulp suspension as well as the headbox and the chlorine levels for mech. water total chlorine, RVV1 free chlorine, hot water total chlorine and mech. water free chlorine. These parameters should therefore be monitored going forward, and if residual peroxide occurs again, their possible interactions and actual impact on the well-being of the bacteria can either be confirmed or denied
90

Affective Rationality

Kerr, Alison Duncan January 2014 (has links)
No description available.

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