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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.
131

Evaluation of selected varieties of wheat, barley, and oats for resistance to barley yellow dwarf virus

Palmer, Louis T. January 1965 (has links)
Call number: LD2668 .T4 1965 P175 / Master of Science
132

Relative efficiency of four aphid species in transmission of barley yellow dwarf virus and use of differential varieties in strain identification

Saksena, Krishna Narain. January 1964 (has links)
Call number: LD2668 .T4 1964 S15 / Master of Science
133

An analysis of the relative weight (Wr) of yellow perch from Indiana waters of Lake Michigan, 1984-91

Tolentino, Scott A. January 1992 (has links)
Relative weight (Wr) of yellow perch (Perca flavescens) was evaluated for fish collected from the Indiana waters of Lake Michigan in June, July and August of 1976 and 1984-1991. Computation of Wr was completed for individual fish in 20 mm intervals over the size range from 100-219 mm using Wr = (W/Ws) 100 where W=weight of a fish in grams and Ws=standard weight for a fish of the same length. Length was highly correlated with weight in all years for males, females and sexes combined (r=0.97-0.99). Distributions of predicted weights for fish at 130 mm and 250 mm were at or near modes of the populations used to construct the Ws equation for yellow perch. Relative weights consistently decreased with increasing size in all years for males, females and sexes combined. Using 1976 length-weight data when the yellow perch population was sparse and fast growing as a standard (100%) for comparison, relative condition factors (Q) increased with increasing size in some years and decreased with increasing size in others for males females and sexes combined and it did not appear to be length dependent. When comparing Wr at 100 mm and 200 mm by sex and month, f hales had higher Wr than males at 100 mm in seven of nine years in June, six of nine years in July and only four of nine years in August. Female fish also had higher Wr than males at 200 mm in eight of nine years in June and July and six of nine years in August. There appeared to be no consistent pattern or trend of Wr increasing or decreasing by month for males, females or sexes combined. When Kn was evaluated for 100 mm and 200 mm fish by sex and year, male fish had higher Kn than females at 100 mm in all eight years. Male and female fish at 200 mm were more similar; male fish had higher Kn in three years, lower Kn in three years and equal Kn in two years. No relationships were found at 200 mm comparing Wr or Kn and CPE (quality/ h) for males (r=0.43; r=0.42), females (r=0.12; r=0.13) or sexes combined (r=0.28; r=0.22). Simple linear correlations of proportional stock density (PSD) with Wr and Kn revealed relative weights increased with PSD for 100 mm (r=0.51) and 200 mm (r=0.72) fish. Relative condition factors also increased with PSD for 100 mm fish, however the relationship was weak (r=0.30) but a strong correlation was found between Kn and PSD (r=0.81) for 200 mm fish. Based on these results, it appears that either Kn or Wr may be used inassessing the condition of yellow perch from the Indiana waters of Lake Michigan. / Department of Biology
134

Contagious Deadly Sins: Yellow Fever in Nineteenth-Century New Orleans Literature

Downes, Kathleen M 18 December 2015 (has links)
Throughout the nineteenth century, New Orleans was repeatedly plagued by yellow fever epidemics. In this paper, cultural representations of yellow fever are considered in three novels: Baron Ludwig Von Reizenstein’s The Mysteries of New Orleans (1854-1855), George Washington Cable’s The Grandissimes (1880), and Mollie Evelyn Moore Davis’ The Queen’s Garden (1900). Because the etiology was unknown during the nineteenth century, yellow fever becomes a floating signifier on which to project the ills they observed in New Orleans society. Yellow fever thus becomes a representation of loose sexual mores, as well as a divinely retributive punishment for slavery, or a sign of adherence to an unequal, antiquated, aristocratic and un-American social system. Yellow fever, in these texts, exposes the struggles with race and racial superiority and illuminates tensions between groups of whites as New Orleans became an American city.
135

“Detección temprana del Potato Yellow Vein Virus en cultivos de Solanum tuberosum L. mediante la teledetección”

Carrión Herrera, Cinthya María January 2017 (has links)
El Potato yellow vein virus (PYVV) es un Crinivirus perteneciente a la Familia Closteroviridae, el cual reduce la producción total de papa en América del Sur hasta un 50%. La detección visual de los cultivos es una práctica habitual, pero la enfermedad generalmente se detecta después de que se ha producido un daño significativo a los tejidos fotosintéticos. A través de técnicas de teledetección se puede evaluar el estado nutricional y fitosanitario de las plantas, detectando incidencias de plagas y enfermedades e inferir posibles carencias nutricionales. Con el objetivo de detectar la infección de PYVV en cultivos de papa antes de la aparición de los síntomas visuales se empleó la técnica de teledetección, mediante el uso del espectroradiómetro. Se llevaron a cabo 5 experimentos, empleando 5 variedades de papa: Única, Clon W.A., Canchan INIA, Amarillis y Costanera. La infección con PYVV fue inducida mediante injerto lateral. Se tomaron 3 mediciones espectroradiométricas por cada planta 2 veces por semana durante todo el periodo de observación y se realizó una evaluación visual continua de los síntomas. Asimismo, se confirmó la presencia del virus PYVV mediante RT-PCR. Finalmente, se evaluó el rendimiento de las 5 variedades y se identificó la variedad más susceptible al virus. Se pudo hacer un diagnóstico precoz de la infección por PYVV en las 5 variedades de papa. La variedad Canchan INIA se detectó entre 8 y 14 días antes de la aparición de los síntomas visuales, Única entre 7 y 18 días, Costanera entre 12 y 17 días, Amarillis entre 6 y 12 días, y finalmente Clon W.A. se pudo detectar entre 2 y 11 días antes de la aparición de los síntomas. La variedad Canchan INIA fue la variedad más susceptible al virus, ya que presentó el mayor porcentaje de reducción en el rendimiento, con un 36.63%, seguido de Costanera y Amarillis con un 28.57% y 28.31%, respectivamente. Clon W.A. fue la variedad menos afectada en cuando a la reducción en el rendimiento, con un 6.67%.Potato yellow vein virus (PYVV) is a Crinivirus belonging to the Closteroviridae Family, which reduces the total potato production in South America up to 50%. Visual detection of cultures is a common practice, but the disease is usually detected after significant damage to photosynthetic tissues has occurred. Through remote sensing techniques, it is possible to evaluate the nutritional and phytosanitary status of plants, detecting pest and disease incidences and inferring possible nutritional deficiencies. In order to detect PYVV infection in potato cultures before the appearance of visual symptoms, the technique of remote sensing was used, using the spectroradiometer. Five experiments were carried out, using 5 varieties of potato: Única, Clon W.A., Canchan INIA, Amarillis and Costanera. Infection with PYVV was induced by lateral grafting. Three spectroradiometric measurements were taken per plant 2 times per week throughout the observation period and a continuous visual evaluation of the symptoms was performed. Also, the presence of the PYVV virus was confirmed by RT-PCR. Finally, the yield of the 5 varieties was evaluated and the variety more susceptible to the virus was identified. An early diagnosis of PYVV infection could be made in all 5 potato varieties. Canchan INIA variety was detected between 8 and 14 days before the appearance of visual symptoms, Unica between 7 and 18 days, Costanera between 12 and 17 days, Amarillis between 6 and 12 days, and finally Clon W.A. could be detected between 2 and 11 days before the onset of symptoms. Canchan INIA variety was the most susceptible to the virus, as it presented the highest percentage reduction in yield, with 36.63%, followed by Costanera and Amarillis with 28.57% and 28.31%, respectively. Clon W.A. was the least affected variety when compared to the reduction in yield, with 6.67%.
136

Aldous Huxley’s Dichotomized Beginning towards Spirituality : An Analysis of Religious Aspects in Crome Yellow

Lundqvist, Lisa January 2018 (has links)
This essay is an analysis of the religious aspects of Crome Yellow. The main focus is to discover what Aldous Huxley’s views on religion were at the time he wrote Crome Yellow and to explore how Huxley’s contemporary surroundings influenced his views on religion. Huxley was born into a family and a society where there was a conflict between science and religion and this conflict together with the crises of his early life, came to affect him greatly. This essay conducts an analysis of Crome Yellow by utilizing Peter Berger’s theory of social construction, which includes information about Huxley’s contemporary surroundings. Huxley seems to have been ambiguous towards religion. He was concerned about the future of society and opposed to organized religion. He was longing for answers and meaning, and he had begun to form a spiritual belief where colour and light are central. These spiritual aspects can be seen as the beginning of Huxley’s spiritual enlightenment.
137

Recording Review of Georgia Yellow Hammers & Associates

Olson, Ted 06 November 2017 (has links)
Review of Georgia Yellow Hammers & Associates: Vols. 1-4
138

A Genetic Investigation of a Yellow Plant Color Characteristic in Winter Wheat

Evans, John Oscar 01 May 1962 (has links)
The objective in wheat hybridization primarily is to obtain new varieties which are of a greater agronomic value than existing varieties. Frequently, however, crosses which obviously will not produce superior commercial types are made and studied in order to obtain genetic information which may be useful to the breeder. This latter phase of breeding, i.e., the accumulation of genetic information, provides the basis for this study.
139

Yellow perch (Perca flavescens) biomass responses to different levels of phytoplankton and benthic production in Lake Memphremagog, Quebec

Nakashima, Brian Shyozo January 1974 (has links)
No description available.
140

Marine ecology of offshore and inshore foraging penguins : the Snares penguin Eudyptes robustus and Yellow-eyed penguin Megadyptes antipodes

Mattern, Thomas, n/a January 2007 (has links)
Seabirds have become adapted for foraging in an oceanic environment that can be highly dynamic. Oceanographic processes determine the spatial distribution of seabird prey, while seasonality often has a temporal influence on prey availability. In penguins, these factors are reflected in the different species� foraging strategies. Penguins can broadly be categorized as inshore foragers that live in subtropical to temperate regions and profit from a stable food supply throughout the year close to their breeding sites, and offshore foragers that breed in a pelagic environment at higher latitudes where oceanographic processes and seasonality create much more dynamic, temporally limited prey situations. In this light, offshore foragers can be expected to be much more flexible in their foraging behaviour so as to quickly respond to changes in a dynamic marine environment, while inshore foragers are more likely to exhibit predictable foraging patterns. I examined the foraging ecology of two New Zealand penguin species - the offshore foraging Snares penguin Eudyptes robustus and the inshore foraging Yellow-eyed penguin Megadyptes antipodes and how their foraging strategies reflect an adaptation to the marine environment they exploit. Diet composition of breeding Snares penguins (incubation and early chick-guard) was determined using the water-offloading method. Before the chicks hatched, the penguins generally brought little food back from their long foraging trips. During chick-guard, the stomach contents comprised mainly of crustaceans (~55%), fish (~24%) and cephalopods (~21%). However, the presence at times of many fish otoliths and squid beaks suggests that the latter two prey classes may play an even more important role in the adults� diet than the simple percentages based on mass suggest. The penguins� nesting routines were strongly synchronised between the years and correlated with the onset of the spring planktonic bloom. Using GPS data loggers and dive recorders I found that during the incubation phase, male penguins that performed long (ca. 2 week) foraging trips exhibited a strong affinity to forage in the Subtropical Front some 200 km east of the Snares. At that stage (late mid-October) the front featured elevated chlorophyll a concentrations, a pattern that can be observed every year. Thus, it seems that the front represents a reliable and predictable source of food for the male penguins. After the males returned, the female penguins also performed long foraging trips (<1 week) but never reached the front, primarily because they had to time their return to the hatching of their chicks. After the chicks had hatched, the female Snares penguins were the sole providers of food. At this stage, the penguins performed short foraging trips (1-3 days) and foraged halfway between the Snares and Stewart Island (ca. 70-90 km north of the Snares), where nutrient-rich coastal waters flow eastwards to form the Southland Current. The penguins concentrated their diving effort in these waters, underlining the importance of the warm coastal waters as a food source for breeding Snares penguins. However, diving behaviour between 2003 and 2004 differed with penguins searching for prey at greater depths in the latter year. This underlines the Snares penguins� behavioural flexibility in response to a changing marine environment. The Yellow-eyed penguins as typical inshore foragers showed very consistent foraging patterns at all stages. GPS logger deployments on penguins at Oamaru revealed that the birds foraged almost exclusively at the seafloor and targeted specific areas that featured reefs or epibenthic communities. As a result, the penguins� at-sea movements appeared conservative and at times almost stereotypic. Nevertheless, a comparison of Yellow-eyed penguins breeding on the adjacent Codfish and Stewart islands revealed a degree of plasticity in the species� foraging behaviour. Birds from Codfish Island extended their foraging ranges considerably and switched from primarily bottom to mid-water foraging during the post-guard stage of breeding. It seems likely that this switch is a result of enhanced feeding conditions (e.g. increased prey abundance/quality) in an area further away from the island, but the time required to get there renders this strategy not viable when chicks are small and need to be guarded and fed on a daily basis. As such, the change of behaviour represents a traditional pattern rather than a dynamic response to a sudden change in the marine environment. In comparison, penguins from Stewart Island showed consistent foraging patterns during all stages of breeding. Given the high levels of chick starvation on Stewart Island, the lack of plasticity in foraging behaviour is surprising and might indicate that Yellow-eyed penguins find it difficult to react quickly to a sub-optimal food situation. Overall, it seems that Yellow-eyed penguins show a specialisation for a consistent benthic environment and, thus, lack the behavioural flexibility apparent in Snares penguins, which find their food in a changing pelagic marine environment.

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