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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.
511

Towards a plant-based method of guiding CO₂ enrichment in greenhouse tomato

Edwards, Diane Roselyn 05 1900 (has links)
Atmospheric CO₂ enrichment is employed by greenhouse tomato growers to increase fruit yields, and CO₂ applications are managed according to atmospheric set points or CO₂ injection rates. These methods do not immediately focus on the targets of CO₂ applications: plant performance and the regulation of plant carbon status. This thesis explores several plant-based approaches that may have potential for use in the management of CO₂ in greenhouse tomato production. Three plant-based approaches to CO₂ management were explored in commercial and experimental tomato greenhouses. These were: (1) simulation modeling, (2) non-destructive analysis of growth and (3) the status of plant carbon reserves. A cost and benefit analysis (c/b) using simulation modeling was carried out using grower-collected greenhouse environment and yield data. Simulation modeling was useful for retrospectively determining c/b of several CO₂ scenarios. The model was effective in predicting long term yields, but not short term yield variations, which limits its application for CO₂ management. Non-destructive measures of growth: stem length and diameter, leaf area and fruit load were found to be too sluggish for daily CO₂ dosing decision-making. Finally, plants growing under CO₂ enrichment can deposit substantial carbon as starch in their leaves. Plant carbon status was evaluated by determining the spatial distribution of leaf starch in the shoot and by following its variation diurnally and after the onset of CO₂ enrichment. As starch is difficult to measure by a grower, leaf mass per unit area (LMA) was also monitored for assessment as a surrogate measure for starch. Leaves in positions 7 to 9 were identified as the most meaningful in the shoot to sample. Diurnal profiles indicated these leaves carryover substantial starch from one day to the next. Monitoring starch at its peak time of accumulation (14 h to 16 h), at sunset and sunrise will indicate how much the peak starch reserves are used overnight. If starch remains high between peak and sunrise the following day, then the plants are in a carbon-surplus state and CO₂ enrichment could be postponed. For upper canopy leaves LMA is substantially influenced by starch and thus is a promising surrogate.
512

Identification of bacterial pathogenic gene classes subject to diversifying selection

Sumir Panji January 2009 (has links)
<p>Availability of genome sequences for numerous bacterial species comprising of different bacterial strains allows elucidation of species and strain specific adaptations that facilitate their survival in widely fluctuating micro-environments and enhance their pathogenic potential. Different bacterial species use different strategies in their pathogenesis and the pathogenic potential of a bacterial species is dependent on its genomic complement of virulence factors. A bacterial virulence factor, within the context of this study, is defined as any endogenous protein product encoded by a gene that aids in the adhesion, invasion, colonization, persistence and pathogenesis of a bacterium within a host. Anecdotal evidence suggests that bacterial virulence genes are undergoing diversifying evolution to counteract the rapid adaptability of its host&rsquo / s immune defences. Genome sequences of pathogenic bacterial species and strains provide unique opportunities to study the action of diversifying selection operating on different classes of bacterial genes.</p>
513

L'enrichissement par la plantation sous couvert : les facteurs qui influencent le développement de plants de feuillus durant la phase d'établissement

Lapointe, Mélanie January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
514

Pažeidėjo gautos naudos išreikalavimo, kaip civilinio teisių gynimo būdo, taikymo ypatumai / Account of profits as the civil remedy: key aspects

Lileikis, Tomas 23 June 2014 (has links)
Šiame magistro darbe nagrinėti pažeidėjo gautos naudos išreikalavimo, kaip civilinio teisių gynimo būdo, ypatumai. Pirmoje darbo dalyje pateikiamas nagrinėjamos temos koncepcinis įvertinimas ir kiti bendrieji klausimai. Išaiškinta, kad pažeidėjo gauta nauda gali būti išreikalauta pagal žalos atlyginimo taisykles. Būtent, vadovaujantis CK 6.249 straipsnio 2 dalimi, pažeidėjo gauta nauda pripažįstama nukentėjusiojo nuostoliais tiek, kiek nukentejusiojo netiesioginiai nuostoliai atitinka pažeidėjo gautą naudą. Likusi dalis išreikalaujama remiantis turto gavimo be pagrindo ir nepagrįsto praturtėjimo normomis. Antrojoje dalyje išanalizuotos bendrosios pažeidėjo gautos naudos išreikalavimo, kaip civilinio teisių gynimo būdo, taikymo pagrindai ir sąlygos. Prieita prie išvados, kad kaltė negali būti būtina sąlyga taikant nepagrįsto praturtėjimo normas. Pateikta analizė, kad subsidiarus nepagrįsto praturtėjimo taikymas turi būti suprantamas taip: pirmiausia turi būti remiamasi civilinės atsakomybės normomis, jei jų taikymas negalimas arba nepasiekiamas norimas rezultatas, papildomai taikomos nepagrįsto praturtėjimo normos jam pasiekti. Trečioji dalis skirta veiksnių, turinčių įtakos pažeidėjo gautos naudos dydžiui, analizei. Nurodoma, kad gauta nauda turi būti suprantama ne tik kaip turto padidėjimas, bet ir nesumažėjimas. Motyvuojama, kad priklausomai nuo neteisėtų veiksmų pobūdžio, gautos naudos išraiškos forma gali būti tiek kaina, tiek vertė. Tam, kad nebūtų pernelyg išplečiamos... [toliau žr. visą tekstą] / The subject matter of the article is to reveal the issues of an account of profits remedy. The substance of aforementioned remedy is considered in the first part of this article. It is asserted that profit made by wrongful conduct must be claimed in accordance to the essential function of civil liability – compensation. Article 6.249 part 2 of Lithuanian Civil code operates to strip a defendant that amount of profit which coincides with the plaintiff‘s indirect damages. The rest profit made by wrongful conduct is reversed by action in unjustified enrichment. The circumstances in which annotated remedy is available is rationalised and explained in the second part of the article. One of the drawn conclusions is that fault can not be a prerequisite for action based on unjustified enrichment. It is submitted that subsidiarity denotes the subordination of action in unjustified enrichment where another claim in fact offers a claimant a basis of recovery. However, the action in unjustified enrichment must not be excluded when the claimant is barred to recover his loss by the primary action. Third part of this article introduces the essential yardsticks which determine the measurement of profit accrued to the defendant. It is preferred that the profit accrued to the defendant should be measured by actual profit made and, then appropriate, by expense saved. It is proved that the benefit conferred on the defendant is measured either by market value or price received. The measurement... [to full text]
515

En jämförelse av beteendeeffekter hos slaktsvin av olika typer av miljöberikning / A comparison of behaviour in fattening pigs with different types of environmentalenrichments

Nygren-Fasth, Veronica January 2014 (has links)
Hos grisar finner man flera stereotypiska beteenden, som rörbitning och svansbitning. Dessa beteenden är relativt vanliga hos grisar. En miljöberikning definieras som förbättring av ett djurs välfärd, både psykologisk och fysiologiskt, genom förändringar hos djurets omgivning. Denna studie har undersökt om miljöberikningar kan minska stereotypiska beteenden hos grisar. De två olika miljöberikningar som har använts är en jutesäck fylld med halm och en Jolly Ball™. De tre stereotypiska beteendena som studerades var rörbitning, svansbitning och bukmassage. Studien utfördes på 107st grisar uppdelade på 12 boxar, under totalt tre veckor. Alla tre stereotypiska beteenden minskade statistiskt signifikant . Detta visar att båda miljöberikningarna hade en positiv effekt på grisarna då de minskade deras stereotypiska beteenden. De interagerade mer med jutesäcken fylld med halm än vad det gjorde med Jolly Ball™.  Grisarna föredrog den miljöberikningen som var omformbar, förstörbar, ätbar, tuggbar, vilket går i linje med liknande studier. / Among fattening pigs you find several stereotypical behaviours, such as bar-biting and tail-biting. These behaviours are quite common among domestic pigs. Environmental enrichments are often used to reduce stereotypical behaviours in animals.  An environmental enrichment is defined as an improvement of an animal’s welfare, both psychologically and physiologically, through changes in the environment of the animal. With this study, different environmental enrichments were studied to see if they can reduce stereotypical behaviour among fattening pigs. The two different environmental enrichments used were a jute sack filled with straw and a Jolly Ball™. The stereotypical behaviours that were looked at were bar-biting, tail-biting and belly-nosing. The study was carried out on 107 pigs divided into 12 pig boxes, during 3 weeks in total. All three stereotypical behaviours decreased significantly. This shows that the environmental enrichments had a positive effect on the pigs, since they reduced their stereotypical behaviour. The pigs interacted more with the jute sack than they did with the Jolly Ball™.  The pigs preferred the environmental enrichment that was destructible, edible, deformable and chewable, which fits well into similar studies that have been executed.
516

Investigation Of The Relationship Between Aerosol And Rainwater Composition

Turkum, Ahmet 01 September 2004 (has links) (PDF)
Chemical composition of particles and rain water at three sites in Turkey were extensively compared to determine if there is a relationship between aerosol and rain composition. If such relationship exists, it can allow one to construct rain water composition using aerosol data. This is important because, rain composition data is scarce as sampling and analysis of very low concentrations of elements and ions in rain water is more difficult compared to sampling and analysis of atmospheric aerosol. Results showed that aerosol composition can be closely reflected in composition of rain water if below cloud processes dominate over the incloud processes. This is clearly observed for crustal elements in all stations and for most of the elements in urban Ankara station. However, in rural stations there were differences in rain and aerosol that is attributed to significant contribution from in cloud processes. Seasonal patterns and enrichment factors observed in aerosol composition showed general agreement with corresponding temporal variations observed in rain water concentrations of elements, but short term variations became visible only if data is averaged over a long period of time. These observations suggest that certain features of rain water composition can be constructed from if concentration data is available for aerosols. However it should be noted that there are also significant differences between stations and between elements or element groups, indicating that composition of rain water constructed from aerosol data can only be a crude one. Similarities between rain and aerosol compositions is more pronounced in urban Ankara station compared to rural stations used in this study. Factor analysis performed to aerosol and rain water data sets showed that source types affecting chemical composition of rain and particles are generally the same, bur contribution of each source type to rain and aerosol composition shows differences. Similarly, the source regions, defined by potential source contribution function, affecting aerosol and rain compositions are not identical. In Antalya station Source regions affecting chemical composition of rain water are more local compared to source regions affecting composition of aerosol. Same difference is not observed in Amasra station. Scavenging ratios is found to be a suitable tool to construct rain water composition using aerosol data. Scavenging ratios calculated using paired daily data are more variable both between stations and within a station. Long-term averaged data was found to be more reliable for calculating SRs of elements and ions at all stations.
517

Effects of fertilisation on rhizospheric and heterotrophic soil CO2 efflux in boreal Norway spruce stands /

Olsson, Per, January 2006 (has links) (PDF)
Lic.-avh. Umeå : Sveriges lantbruksUniversity. / Härtill 2 uppsatser.
518

Condictio sine datione : zur Haftung aus ungerechtfertigter Bereicherung im klassischen römischen Recht und zur Entstehung des Bereicherungsrechts im BGB /

Heine, Sonja. January 2006 (has links)
Thesis (doctoral)--Universität, Freiburg im Breisgau, 2005. / Includes bibliographical references.
519

Semantic Enrichment of Ontology Mappings

Arnold, Patrick 04 January 2016 (has links) (PDF)
Schema and ontology matching play an important part in the field of data integration and semantic web. Given two heterogeneous data sources, meta data matching usually constitutes the first step in the data integration workflow, which refers to the analysis and comparison of two input resources like schemas or ontologies. The result is a list of correspondences between the two schemas or ontologies, which is often called mapping or alignment. Many tools and research approaches have been proposed to automatically determine those correspondences. However, most match tools do not provide any information about the relation type that holds between matching concepts, for the simple but important reason that most common match strategies are too simple and heuristic to allow any sophisticated relation type determination. Knowing the specific type holding between two concepts, e.g., whether they are in an equality, subsumption (is-a) or part-of relation, is very important for advanced data integration tasks, such as ontology merging or ontology evolution. It is also very important for mappings in the biological or biomedical domain, where is-a and part-of relations may exceed the number of equality correspondences by far. Such more expressive mappings allow much better integration results and have scarcely been in the focus of research so far. In this doctoral thesis, the determination of the correspondence types in a given mapping is the focus of interest, which is referred to as semantic mapping enrichment. We introduce and present the mapping enrichment tool STROMA, which obtains a pre-calculated schema or ontology mapping and for each correspondence determines a semantic relation type. In contrast to previous approaches, we will strongly focus on linguistic laws and linguistic insights. By and large, linguistics is the key for precise matching and for the determination of relation types. We will introduce various strategies that make use of these linguistic laws and are able to calculate the semantic type between two matching concepts. The observations and insights gained from this research go far beyond the field of mapping enrichment and can be also applied to schema and ontology matching in general. Since generic strategies have certain limits and may not be able to determine the relation type between more complex concepts, like a laptop and a personal computer, background knowledge plays an important role in this research as well. For example, a thesaurus can help to recognize that these two concepts are in an is-a relation. We will show how background knowledge can be effectively used in this instance, how it is possible to draw conclusions even if a concept is not contained in it, how the relation types in complex paths can be resolved and how time complexity can be reduced by a so-called bidirectional search. The developed techniques go far beyond the background knowledge exploitation of previous approaches, and are now part of the semantic repository SemRep, a flexible and extendable system that combines different lexicographic resources. Further on, we will show how additional lexicographic resources can be developed automatically by parsing Wikipedia articles. The proposed Wikipedia relation extraction approach yields some millions of additional relations, which constitute significant additional knowledge for mapping enrichment. The extracted relations were also added to SemRep, which thus became a comprehensive background knowledge resource. To augment the quality of the repository, different techniques were used to discover and delete irrelevant semantic relations. We could show in several experiments that STROMA obtains very good results w.r.t. relation type detection. In a comparative evaluation, it was able to achieve considerably better results than related applications. This corroborates the overall usefulness and strengths of the implemented strategies, which were developed with particular emphasis on the principles and laws of linguistics.
520

Ecological impacts of biodiversity enrichment in oil palm plantations

Teuscher, Miriam 27 November 2015 (has links)
No description available.

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