• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 256
  • 127
  • 39
  • 22
  • 18
  • 11
  • 11
  • 11
  • 11
  • 11
  • 11
  • 10
  • 7
  • 7
  • 4
  • Tagged with
  • 657
  • 103
  • 74
  • 64
  • 58
  • 53
  • 42
  • 37
  • 36
  • 34
  • 33
  • 30
  • 29
  • 28
  • 28
  • 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.
191

Meritokratické dělení: restrukturalizace štěpných linií na Západě? Případ hnutí Žlutých hvězd. / The meritocratic division: a restructuration of cleavages in the West? - Insight from the Yellow Vests movement.

Forel, Alexis January 2021 (has links)
The attempts to understand discontent and populist surges in the West, especially in recent years, led to an abundance of research, comments, and speculations. Some thinkers asserted that such events are the symptoms of a cleavage restructuration in liberal democratic societies that would be centered around the question of merit. Research generally links higher education and general success in life to satisfaction and relative support of the established order. On the contrary, lesser educated and successful individuals tend to question this state of affairs. A cleavage revolving around success and education would consequently replace previous divisions, such as the usual right-left opposition, but also come on top of other schisms, mainly spatial ones. This thesis offers to verify the existence of such a cleavage with a case study of the Yellow Vests movement, in France. Analyzing the discourse of the representants of the meritocracy, Emmanuel Macron and his government, it finds trends that support the existence of such an underlying conflict.
192

Evaluation of Management Tools for Stripe Rust in Hard Red Spring Wheat and Assessment of Virulence Phenotypes and Aggressiveness in Puccinia striiformis Isolates

Evin, Bryn Anndi January 2019 (has links)
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is an economically important foliar disease of wheat (Triticum aestivum). In the last decade, losses from stripe rust in North Dakota (ND) have increased, peaking at 5% in 2015. Three research studies were conducted to address questions on the pathogen, varietal resistance, and integrated management. The objective of the first study was to (i) identify virulent phenotypes of Pst isolates collected from ND from 2015 to 2017 and assign races, and (ii) determine the effect of temperature on in vitro urediniospore germination, latency, and lesion spread. Across the three years, five races were detected with PSTv 37 being the most common. The highest urediniospore germination occurred at 12oC followed by 16oC. Pst isolates had shorter latency at 21oC and larger lesion spread at 16oC. The objective of the second study was to evaluate seedling resistance and adult plant resistance in the North Dakota State University spring wheat breeding program using races PSTv 37 and PSTv 52. Results from seedling experiments indicated only four and two lines were resistant to PSTv 52 and PSTv 37, respectively. Adult plant resistance experiments were unsuccessful in 2019, and will be conducted again in the future. The objective of the third study was to develop fungicide timing recommendations for wheat rust (stripe and leaf) based on varietal resistance and time of disease onset. Rust developed in five of the eight field trials, and timing of disease onset was categorized by growth stage (tillering, flag leaf, or early-flowering). Results indicated fungicide application timing was influenced by timing of disease onset and varietal resistance. When rust was detected at the tillering growth stage on the susceptible variety, the best time to apply a fungicide was at Feekes 9. When rust was detected at flag leaf or beyond on a susceptible variety, a fungicide application at Feekes 10.51 provided the adequate disease reduction and protection of yield. Results from these research studies provide a better understanding of Pst, determined seedling resistance in the breeding program, and provides field data to refine management recommendations for wheat rusts in ND. / North Dakota Wheat Commission / State Board of Agricultural Research and Education
193

Zhao Jiping's Film Score in Yellow Earth (1984): Constructing and Subverting Perceptions of Diegetic Boundaries

Munger, Justin 04 May 2022 (has links)
This thesis examines how Zhao Jiping's film score in Yellow Earth (1984) establishes distinct identities for the diegetic and non-diegetic (presentational) space, as well as how Zhao manipulates the audience's perception of musical-spatial boundaries in order to create moments of musical significance during the "river scenes." To model the diegesis, I use a perception model approach combined with work by Winters and Yacavone. This frames the diegesis in relation to reality, without being beholden to it, and attributes to the audience an active role in constructing the diegesis, internally and subjectively expanding on fragments presented by the film. I then characterize the music of the diegesis as being representative of the Shaanbei region of China, using folk singing and instruments indigenous to the region. The music of the presentational space uses melodic material derived from the diegetic music, supported by orchestral music in a style similar to mixed instrument ensembles in Model Works. During the "river scenes", Zhao's music gradually detaches the audience's sense of anchoring in the diegetic space and pivots into the presentational space, creating an intense contrast that supports the narrative significance of the scene. Afterwards, similar techniques are then used to gradually re-anchor the audience back into the diegesis. Using models of the diegetic and presentational spaces that incorporate recent shifts in academic perspective, this thesis demonstrates Zhao Jiping's nuanced understanding of how an audience perceives musical space, both by creating distinct identities for the diegetic and presentational spaces, and by manipulating audience perception of space in order to create moments of musical significance.
194

Parental care and female mate choice in yellow warblers (Dendroica petechia)

Lozano, George A. January 1996 (has links)
No description available.
195

A study of ozone effects on yellow birch (Betula alleghaniensis Britt.) and paper birch (Betula papyrifera Marsh.) seedlings inoculated with mycorrhizal fungi /

Krupczak, Deborah L. 01 January 1989 (has links) (PDF)
No description available.
196

Development and Application of a Method for Determination of Metals in Environmental Sediments

Nguyen, Tuong Van 04 May 2023 (has links)
No description available.
197

Analyses of Arabidopsis Yellow Stripe-Like (YSL) Family of Metal Transporters

Chu, Heng-Hsuan 01 February 2010 (has links)
Iron is one of the most important micronutrients used by living organisms. Iron is frequently a limiting nutrient for plant growth, and plants are a major source of iron for human nutrition. The most prominent symptom of iron deficiency in plants is interveinal chlorosis, or yellowing between the veins, which appears first in the youngest leaves. Iron deficiency anemia (IDA) is the number one human nutritional deficiency worldwide. In order to solve the problem of iron deficiency, it is desirable to breed plants that have increased iron in those parts that are consumed by humans. To do this, we must first understand the molecular basis of Fe uptake, transport, and storage in plants. In soil, iron is quickly oxidized to Fe(III), and Fe(III) is relatively insoluble, thus difficult for plants to obtain. Our lab has been working on metal ion homeostasis mechanisms in plants and the ultimate goal of our research is to understand the mechanisms by which plants maintain the correct levels of iron, zinc and copper in each cell and tissue. The Yellow Stripe-like (YSL) family of proteins has been identified based on sequence similarity to maize Yellow stripe 1 (YS1). YS1 transports Fe(III) that is complexed by phytosiderophores (PS), strong Fe(III) chelators of the mugineic acid family of compounds. Non-grass species of plants neither make nor use PS, yet YSL family members are found in non-grass species including Arabidopsis thaliana. YSLs in non-grasses have been hypothesized to transport metals that are complexed by nicotianamine (NA), an iron chelator that is structurally similar to PS and which is found in all higher plants. In this dissertation, Arabidopsis YSL1 and YSL3 are demonstrated to be important in iron transport and also responsible for loading Fe, Cu, and Zn from leaves into seeds. Arabidopsis YSL4 and YSL6 are demonstrated to be involved in iron transport and metal mobilization into seeds. The transport function of Arabidopsis YSL1 and YSL2 are shown be partially overlapping to the function of Arabidopsis YSL3 in vegetative structures, but distinct in reproductive organs. Arabidopsis YSL3 and YSL6 are shown to have distinct functions in planta.
198

Optimal Reproductive Strategy in Yellow-Bellied Marmots: Unveiling the Consequences of Age at First Reproduction on Survival and Lifetime Reproductive Success

Chabot, Carol-Ann 03 October 2023 (has links)
When to reproduce for the first time is a key question in evolutionary ecology. Indeed, age at first reproduction has clear impacts on population dynamics and fitness. Breeding early in life may impair survival due to a resource allocation trade-off between survival, growth, and reproduction. Postponing reproduction, however, reduces reproductive opportunities and increases the chances of dying before reproducing. Here, I investigate the consequences of age at first reproduction on both survival and lifetime reproductive success by using long-term monitoring data of a population of yellow-bellied marmots (Marmota flaviventer) at the Rocky Mountain Biological Laboratory (Colorado, USA). Mixed models were employed to analyze the relationships between age at first reproduction in females and their lifetime reproductive success, as well as three survival components: longevity, the number of years after first reproduction, and annual survival probability. The results showed that postponing reproduction until 2 years of age increased longevity, but delaying it beyond 2 years did not yield additional survival benefits. Females reproducing for the first time after 3 years exhibited high rates of actuarial senescence. Furthermore, delaying first reproduction beyond 3 years old did not lead to a compensatory increase in lifetime reproductive success that would offset the reduction in survival associated with postponing first reproduction. These results suggest that the optimal age at first reproduction, in terms of survival and reproductive success, is 2 years. The reproductive strategy might be governed by body condition or environmental factors. These findings shed light on the trade-offs between early reproduction and survival, as well as reproductive success, illustrating the complexity of reproductive strategies in relation to individual fitness.
199

An In-Plant Assessment of Heartwood/Sapwood Content in Southern Yellow Pine for Residential Lumber and Industrial Poles and Pilings

Penick, Marlon Rayborn 15 August 2014 (has links)
Knowing and understanding the sapwood and heartwood functions and properties are crucial in pressure-treating southern pine. It is very difficult to penetrate heartwood with chemicals. Therefore, knowing heartwood content before treatment will benefit companies in chemical consumption, treating cycles, and, foremost, cost. In this study, two different assessments were conducted in which lumber and pole heartwood/sapwood data was collected from eight treating plants across five Southeastern states. In both assessments, the data indicated some significant differences between similar products from different vendors, but there was no significant difference in heartwood content between plant locations. The results suggested that the amount of heartwood increases as the size and length of the products increase. These findings can argue that the size of raw materials that vendors use and the products they manufacture have more effect on heartwood content than plant location.
200

Properties of four domestic hardwood species

Carmona Uzcategui, Marly Gabriela 01 May 2020 (has links)
This study aimed to evaluate the physical and mechanical properties of red oak (Quercus spp.), white oak (Quercus spp.), hard maple (Acer saccharum) and yellow-poplar (Liriodendron tulipifera) and compare them to values from past publications. Mechanical testing was conducted on small, clear, defectree specimens from red oak, white oak, hard maple and yellow-poplar following the standard ASTM D143. Percentage of latewood, moisture content, specific gravity, modulus of elasticity (MOE), modulus of rupture (MOR), compression parallel and perpendicular to the grain and Janka hardness were determined. Results indicated that mechanical properties for red oak, white oak, hard maple and yellow poplar have not changed substantially because the average values remain in a range that is very close to the ones published in past studies. Thus, values from the Wood Handbook can still be used for engineering purposes.

Page generated in 0.1737 seconds