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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.
111

Coevolution of male signals and female preferences in <em>Drosophila montana</em> and <em>D. virilis</em>

Saarikettu-Känsälä, M. (Mari) 30 November 2011 (has links)
Abstract Divergence of behavioral traits (e.g. courtship rituals, habitat choice) has had a major impact on species formation and isolation. Species-specific courtship rituals preventing species hybridization may arise as a by-product of natural selection during spatial isolation or through direct action of natural selection to prevent species hybridization after a secondary contact. Coordination leading to the assumption of coevolution of signals and preferences is a prerequisite for effective courtship signaling between a male and a female of the same species. We found a reasonable amount of variation in the mate traits within the Drosophila montana and D. virilis species, but our findings did not reveal evidence of the coevolution between the male courtship signals and female preference for these signals. Variation also did not cause isolation within species. The form of female preference for carrier frequency of male song was found to be stabilizing even in changing environments, when female preference for the carrier frequency and pulse length of the male song was measured at ambient temperature. D. montana females always preferred males with high frequency songs, which probably advertises the male condition. The frequency of male song decreased due to male aging, although males with larger body size were able to maintain frequencies better. Ageing also had a deterioration effect on male reproductive success. The importance of male courtship song was not only highlighted in mate choice, but also in species-recognition. We were able to persuade D. montana females to copulate with alien D. lummei species by playing them simulated song resembling the song of conspecific males. Simulated courtship songs were demonstrated to be a practical tool in studies of preference between sexually isolated Drosophila species. / Tiivistelmä Kosintapiirteiden (esim. kosintarituaalit, habitaatin valinta) vaihtelevuudella on ollut suuri vaikutus lajien muodostumisessa ja eriytymisessä. Lajien välisiä risteytymisiä estäviä lajispesifisiä kosintarituaaleja voi syntyä luonnonvalinnan sivutuotteena spatiaalisen eristäytymisen aikana tai luonnonvalinnan suoralla vaikutuksella estämään lajiristeymät lajien uudelleen kohdatessa. Tehokkaan koiraan ja naaraan välisen kosintaviestinnän edellytyksenä on koordinointi, minkä vuoksi on oletettavaa, että signaalien ja vasteiden välillä on yhteisevoluutiota. Löysimme kohtuullisen määrän vaihtelevuutta kosintapiirteissä Drosophila montana – ja D. virilis – lajeilla, mutta emme löytäneet todisteita koiraan kosintasignaalien ja naaraan näihin signaaleihin kohdistamien vasteiden välisestä yhteisevoluutiosta. Vaihtelu ei myöskään aiheuttanut isolaatiota lajien välille. Naaraan koiraan kosintalaulun kantofrekvenssiin osoittaman vasteen funktion muodon havaittiin olevan tasapainottava jopa vaihtelevissa ympäristöissä, kun naaraan kantotaajuuteen osoittamaa vastetta mitattiin eri lämpötiloissa. D. montana naaraat suosivat koiraita, joilla oli korkeataajuinen kosintalaulu. Laulun korkea taajuus kertoo luultavasti naaraalle koiraan fyysisestä kunnosta. Koiraan laulun frekvenssin havaittiin laskevan koiraan ikääntyessä, mutta isommat koiraat pystyivät paremmin säilyttämään korkean taajuuden laulussaan. Ikääntyminen heikensi myös koiraan lisääntymismenestystä. Koiraan kosintalaulun tärkeys ei korostunut pelkästään parinvalinnassa, vaan myös lajintunnistuksessa. Pystyimme suostuttelemaan D. montana –naaraat parittelemaan vieraan D. lummei –lajin kanssa käyttämällä simuloituja kosintalauluja, jotka osoittautuivat käytännöllisiksi välineiksi tutkittaessa naaraan vasteita seksuaalisesti eriytyneillä Drosophila-lajeilla.
112

Structural and Kinematic Evolution of Eocene-Oligocene Grasshopper Extensional Basin, Southwest Montana

Kickham, Julie C. 01 May 2002 (has links)
The Grasshopper basin of southwest Montana is a complex east-dipping graben containing five unconformity-bounded sequences of Tertiary sedimentary rocks. The Eocene-Oligocene basin lies within the northern Rocky Mountain Basin and Range province. Geologic mapping in five and a half 7.5 minute quadrangles indicates that at least three distinct phases of extension characterize the Cenozoic tectonic evolution of Grasshopper basin from approximately 46 Ma toMa. The significant phases of extension in Grasshopper basin were phases 1 and 3. During the first phase of extension (46-27 Ma) the nonplanar Muddy-Grasshopper fault was initiated and 90% of the basin fill was deposited. At least 7 km of dip-slip displacement along this fault controlled the deposition of the Medicine Lodge beds (3.5 km thick) and development of a transverse fold train and a longitudinal anticline. The second phase of extension (late Eocene-early Oligocene) resulted in northwest-southeast trending extensional structures and was probably coincident with deformation along the Lemhi Pass fault (20 km to the southwest). The third phase of deformation (early Oligocene-middle Miocene) dismembered the once larger protobasin into smaller subbasins and tilted the northwest-dipping limb of the longitudinal anticline. The structures formed during this phase have north-south and northeast trends. Little sediment was deposited during phases 2 and 3. Overall >85% E-W extension accrued. Extensional folds are common in Grasshopper basin and formed during all three phases of extension. One orthogonal fold set was recorded. Two-dimensional kinematic analysis of the longitudinal Bachelor Mountain anticline shows that this fold is a double-­rollover that probably developed above a longitudinal ramp in the Muddy-Grasshopper fault. The transverse folds are the result of the changing strike of the downward­-flattening Muddy-Grasshopper fault. A transverse syncline developed above a convex up part of the fault whereas a transverse anticline formed above a concave up part of the fault that reflects changes in the strike of the fault. Three-dimensional inclined shear probably created this geometry.
113

Development of a Frost Heave Test Apparatus

Lay, Russell David 11 August 2005 (has links) (PDF)
Frost heave damage to roadways costs millions of dollars every year. The need for an improved understanding of the fundamental mechanisms associated with frost heave and methods for efficiently improving frost-susceptible materials prompted the Department of Civil and Environmental Engineering at Brigham Young University (BYU) to undertake a project to design, construct, and verify the functionality of a new frost heave testing apparatus. Frost heave research has been carried out for more than 75 years. The equipment used to conduct this testing has advanced in accuracy and utility over the years. To establish a background in past and current frost heave research, a survey of 12 frost heave devices, including their construction and capabilities, was performed in this research. Several design objectives were then delineated, and a nine-specimen frost heave device was designed and constructed to meet the specifications. The apparatus uses one collective heat source and one collective heat sink for all nine specimens. Heave data and temperature data are collected electronically, while the weights of the specimens before and after frost heave testing are measured manually. Preparatory tests were conducted to confirm the functionality of the data acquisition systems, the uniformity of conditions experienced by all specimens, and the replication of natural roadway freezing conditions. Once preparatory testing was complete, a full-scale frost heave test was performed using the apparatus to investigate the efficacy of cement stabilization in reducing the frost susceptibility of a Montana silt and to validate the functionality of the finished device. Results from the testing indicate that adding 2.0 percent cement actually induces frost heave in excess of that exhibited by the untreated soil. However, additions of 3.5 percent and 5.0 percent were found to be effective in preventing frost heave. Although minor, recommendations for further improvements to the frost heave apparatus include provisions to further decrease the thermal gradient across the specimen and installation of an automatic temperature control device for the water source.
114

Institutions of Integration: The Incorporation of Frontiers in Modern Democracies, 1864-1912

Fanning, Soren I. 26 October 2010 (has links)
No description available.
115

Development of cyclic ramp-to-basin carbonate deposits, lower Mississippian, Wyoming and Montana

Elrick, Maya 09 September 2008 (has links)
The Lower Mississippian Lodgepole/lower Madison Formations (20-225 m thick) developed along a broad (>700 km) stormdominated cratonic ramp. Three types of shallowing-upward cycles (5th order) are recognized across the ramp-to-basin transition. Peritidal cycles consist of very shallow subtidal facies overlain by algal-laminated tidal flat deposits, which are rarely capped by paleosol/breccia layers. Shallow subtidal cycles consist of stacked ooid grainstone shoal deposits or deeper subtidal facies overlain by ooid-skeletal grainstone caps. Deep subtidal cycles occur along the outer ramp and ramp-slope and consist of sub-storm wave base limestone-argillite, overlain by graded limestone, and are capped by storm-deposited skeletal-ooid grainstone. They pass downslope into rhythmically interbedded limestone and argillite with local deepwater mud mounds; no shallowing-upward cycles occur within the ramp-slope facies. Average cycle periods calculated along the outer ramp range from 30-110 k.y. The cycles likely formed in response to 5th order (20-100 k.y.) sea level oscillations. The cycles are stacked to form three 3rd to 4th order depositional sequences which are defined by regional transgressive-regressive facies trends. The ramp margin wedge (RMW) developed during long-term sea level fall lowstand conditions and consists of cyclic crinoidal bank and oolitic shoal facies which pass downdip into deep subtidal cycles. The transgressive systems tract (TST),which onlapped the ramp during long-term sea level rise, includes thick deep and shallow subtidal cycles; peritidal cycles are restricted to the inner ramp. The highstand systems tract (HST) developed during long-term sea level highstand and fall, and along the ramp is composed of early HST shallow subtidal cycles which are overlain by late HST peritidal cycles; shallow through deep subtidal cycles composed the HST along the ramp-slope. / Ph. D.
116

?DIAS, Aline dos Santos Dias. Ecologia de ep?fitas vasculares em uma ?rea de Mata Atl?ntica do Parque Nacional da Serra dos ?rg?os, Teres?polis, RJ. 2009. / Vascular epiphytes ecology in Atlantic Forest area of Serra dos ?rg?os National Park, Teres?polis, RJ. 2009.

Dias, Aline dos Santos 03 April 2009 (has links)
Made available in DSpace on 2016-04-28T14:56:18Z (GMT). No. of bitstreams: 1 Aline dos Santos Dias.pdf: 3422634 bytes, checksum: dc4b6e67281e315c9d0348b75c811d7d (MD5) Previous issue date: 2009-04-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / ?The epiphytes are plants that use trees as support without being connected to the ground. The epiphytes have wide geographical distribution and could be finding basically in most tropical rain forest, representing 50% of the neotropical vascular flora. The families more representative are Orchidaceae, Bromeliaceae, Araceae and Polypodiaceae. Despite the increase in the number of studies on the epiphytism in Brazil, information on this guild in the remaining forests of Rio de Janeiro state are still scarce. Thus, this study aimed to analyze the composition, richness and guild structure on a forest situated between 500 and 1500 meters over sea level (montana forest) in the Serra do ?rg?os National Park (RJ). In the 60 plots of 100 m2 (0.6 ha), all trees with DBH > 10.0 cm had their diameter and total height measured. All epiphytes were identified and their abundances were estimated for each class of height stipulated for the host trees. The relative frequencies of occurrence of species were calculated for the area as a whole and for host trees as well as for the host trees classes of height, canopy and trunk, and your value of importance calculated. Each species was classified according to their ecological category. The horizontal distribution of species was analyzed using the Morisita index and vertical by ?2 test. Relationship between the morphometric characteristics of host trees and richness and abundance of epiphytes were performed by simple regression analysis. We identified 84 species of epiphytes, in 28 genera and 9 families. The most representative families were Bromeliaceae, Araceae and Polypodicaeae. In this area, the epiphytes richness is considered high when compared with several studies in Brazil. The most frequent species were Microgramma squamulosa, Pleopeltis pleopeltifolia and P. hirsutissimum and a high number were considered rare species. Pleopeltis pleopeltifolia was more frequent in host trees, followed by P. hirsutissimum and M. squamulosa. These species also occurred in high frequencies in other studies, showing its wide geographical distribution and its importance in the composition of this guild. The species with higher importance are epiphytics P. hirsutissimum, P. pleopeltifolia and M. squamulosa, showing the high capacity of these species to occupy the host trees. Most epiphytes in this area (56% of species) are classified as holoepiphytes, as shown in other similar studies. For the horizontal distribution, random distribution pattern were observed for basically all high abundance epiphytes, indicating that this area has a wide availability of resources for the establishment of these species. In vertical distribution, we observed a significant difference in the occupation of the different classes of height of host trees for 53 of 84 species sampled. The highest occurrence of epiphytes was observed in the canopy. There were significant and positive relationship between height and total host trees with the richness and abundance of epiphytes, as well as between DBH and richness and abundance of epiphytes. Thus, the epiphytes respond directly to the structure of the forest where they are found, varying its parameters under different ecological characteristics with structure of forest formation. / ?As ep?fitas s?o vegetais que, durante toda a sua vida ou em algum est?gio dela, vivem sobre as ?rvores, utilizando-as como suporte, sem estarem ligadas ao solo. As ep?fitas possuem uma ampla distribui??o geogr?fica e s?o encontradas em praticamente todas as florestas ?midas, representando cerca de 50% de toda flora vascular neotropical. As fam?lias mais representativas s?o Orchidaceae, Bromeliaceae, Araceae e Polypodiaceae. Apesar do incremento no n?mero de estudos sobre o epifitismo no Brasil, informa??es sobre esta guilda nos remanescentes do Rio de Janeiro ainda s?o escassos. Desta forma, este estudo visou analisar a composi??o, riqueza e a estrutura das ep?fitas vasculares em um trecho de Floresta Ombr?fila Densa Montana do Parque Nacional da Serra dos ?rg?os (RJ). Foram demarcadas 60 parcelas de 100 m2 (0,6 ha), nas quais as ?rvores com DAP > 10,0 cm tiveram seu di?metro e altura total mensurados. Todas as ep?fitas encontradas nos for?fitos foram identificadas, tendo suas abund?ncias estimadas em cada classe de altura estipulada para os for?fitos. As freq??ncias relativas de ocorr?ncia das esp?cies foram calculadas para a ?rea como um todo, para os for?fitos e para as zonas de altura do for?fito, copa e fuste, al?m de terem seu valor de import?ncia calculado. Cada esp?cie foi classificada de acordo com sua categoria ecol?gica. A distribui??o horizontal das esp?cies foi analisada atrav?s do ?ndice de Morisita e a vertical pelo teste de ?2 . Rela??es entre as caracter?sticas morfom?tricas do for?fito e a riqueza e abund?ncia de ep?fitas foram efetuadas atrav?s da an?lise de regress?o simples. Foram identificadas 84 esp?cies de ep?fitas, de 28 g?neros e nove fam?lias. As fam?lias mais representativas foram Bromeliaceae, Araceae e Polypodicaeae. A riqueza de ep?fitas nesta ?rea pode ser considerada alta quando comparada com diversos estudos realizados no Brasil. As esp?cies mais freq?entes foram Microgramma squamulosa, Pleopeltis pleopeltifolia e P. hirsutissimum, sendo consideradas raras a maioria das esp?cies. Pleopeltis pleopeltifolia foi a mais frequente nos for?fitos, seguida de P. hirsutissimum e M. squamulosa. As esp?cies com maiores valores de import?ncia epif?tica foram P. hirsutissimum, P. pleopeltifolia e M. squamulosa, sendo clara a ampla capacidade de ocupa??o dos for?fitos por estas esp?cies. A maioria das ep?fitas nesta ?rea (56% das esp?cies) ? classificada como holoep?fitas, sendo este resultado semelhante a outros estudos. Para a distribui??o horizontal, praticamente todas as ep?fitas tiveram um padr?o de distribui??o aleat?rio, demonstrando, principalmente, que nesta ?rea h? uma ampla disponibilidade de recursos para o estabelecimento destas esp?cies. Na distribui??o vertical, foi observada uma diferen?a significativa na ocupa??o das classes de altura do for?fito para 53 esp?cies das 84 amostradas. A maior ocorr?ncia de ep?fitas foi observada na copa. Houve rela??o significativa e positiva entre a dimens?o dos for?fitos e a abund?ncia e a riqueza de ep?fitas. Assim, as ep?fitas responderam diretamente ? estrutura da floresta onde s?o encontradas, variando seus par?metros ecol?gicos de acordo com a estrutura da forma??o florestal.
117

Biopesticidna aktivnost ekstrakata odabranih biljnih vrsta familije Lamiaceae / Biopesticide activity of the extracts of self-seeding plants of Lamiaceae family

Šućur Jovana 19 November 2015 (has links)
<p>Ispitivan je hemijski sastav etarskih ulja i vodenih ekstrakata tri vrste samoniklih biljaka familije Lamiaceae:&nbsp;<em> Satureja montana&nbsp;</em>L.,&nbsp; <em>Salvia sclarea&nbsp;</em>L.,<em>&nbsp; Clinopodium menthifolium</em>&nbsp; Host. Pored toga, ispitano je delovanje vodenih ekstrakata na korovske i ratarsko-povrtarske biljke, insekte i mikroorganizme, kao i etarskih ulja na insekte.<br />Potvrđeno je da ispitivane vrste imaju insekticidno dejstvoi da nemaju uticaj na rast korisnih mikroorganizama prisutnih u zemlji&scaron;tu.</p> / <p>The chemical composition of essential oils and aqueous extracts of three types of self-seeding plants of the Lamiaceae family are examined. Apart from the composition, the effects of aqueous extracts on weed and vegetable plants, insects and&nbsp; microorganisms are examined. The effects of essential oils on insects are also examined. Insecticidal activity of examined plants is confirmed. It is also confirmed that the examined plants have no effect on the growth of useful microorganisms present in the soil.</p>
118

Size Fractionation of Metabolically Active Phytoplankton and Bacteria in Two Diverse Lentic Systems

Ellis, Bonnie K. 08 1900 (has links)
Simultaneous size fractionation of plankton populations associated with NaH^14CO_3 and ^3H-glucose uptake was employed in eutrophic Lake Texoma (Texas and Oklahoma) and oligotrophic Flathead Lake (Montana). Autoradiography was utilized to determine the role of specific microorganisms in community metabolism. Ultraplankton (0.45-10 μm) dominated plankton numbers and metabolic activity in both aquatic systems. Many of the most abundant species were not the most productive, in terms of inorganic C fixation. Rates of heterotrophic uptake of ^3H-glucose were small in comparison to photolithotrophic uptake in both lakes, Photoheterotrophy was more extensive in Flathead Lake, Autoradiographs indicated that bacteria were responsible for observed photoheterotrophy. Oscillatoria sp. exhibited. mixotrophy in Lake Texoma,
119

Filial Therapy with Native Americans on the Flathead Reservation

Glover, Geraldine J. 05 1900 (has links)
This study was designed to determine the effectiveness of the 10-week filial therapy model as an intervention for Native American parents and their children residing on the Flathead Reservation in Montana. Filial therapy is an approach used by play therapists to train parents to be therapeutic agents with their own children. Parents are taught basic child-centered play therapy skills and practice those skills during weekly play sessions with their children. The purpose of this study was to determine if filial therapy is effective in: 1) increasing parental acceptance of Native Americans residing on the Flathead Reservation of their children; 2) reducing the stress level of those parents; 3) improving empathic behaviors of those parents toward their children; 4) changing the play behaviors of children with their parents who participated in the training; and, 5) enhancing the self-concept of those children. The experimental group parents (N=11) received 10 weekly 2-hour filial therapy training sessions and participated in weekly 30-minute play sessions with one of their children. The control group (N=10) received no treatment during the 10 weeks. All adult participants completed the Porter Parental Acceptance Scale and the Parenting Stress Index. Child participants completed the Joseph Pre-school and Primary Self Concept Screening Test. Parent and child participants were videotaped playing together in 20-minute videotaped play sessions before and after the training to measure empathic behavior in parent-child interactions and desirable play behaviors in children. Analyses of Covariance revealed that the Native American parents in the experimental group significantly increased their level of empathy in their interactions with their children. Experimental group children significantly increased their level of desirable play behaviors with their parents. Although parental acceptance, parental stress, and children's self concept did not improve significantly, all measures indicated positive trends. In addition, this study gives rise to questions regarding the suitability of current self concept measurement instruments for Native American children and possible cultural differences in parent stress and parental acceptance.
120

Analysis of rail rates for wheat rail transportation in Montana; comparing rates in a captive market to one with more intramodal competition

McKamey, Matthew January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Michael W. Babcock / Today’s rail industry is the outcome of years of regulatory and technological change. Since the passage of the Staggers Rail Act of 1980 the industry has seen consolidation through mergers and acquisitions. The rail industry in Montana has a rich rail history that includes the completion of a northern east-west route over 100 years ago that provided a commerce route from the interior of the US heartland to the ocean ports in the Pacific Northwest. In those hundred years the rail traffic across Montana has seen dramatic change. In the past, those routes have provided access for Montana freight; today those routes primarily serve the needs of consumers and industries far beyond Montana. While the state’s economy is primarily agricultural, the largest user of rail transportation is the energy industry. This leaves the agriculture industry with a lower priority for access, providing a quandary for rail service for the grain industry in the state. In a state where more than eight national and regional rail carriers once operated, Montana is now only serviced by a small handful, one of which operates over 80% of the rail miles within its borders. Furthermore that carrier provides service through those regions that are almost strictly agricultural, needing the greatest access to the most cost effective means of transportation for the bulk movement of grain. The objectives of this thesis are to develop a model to measure railroad costs and competition; determine the principal cost determinants and measure intramodal competition by comparing the rates in a captive market (Montana) to one with more intramodal competition (Kansas).

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