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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

Comparison of Short Staple Planting Dates

Farr, C. R. 02 1900 (has links)
No description available.
132

Continuous Cropping

Cannon, M. D. 02 1900 (has links)
No description available.
133

Short Season Double Row Spacing Variety Trial

Stedman, Sam 02 1900 (has links)
No description available.
134

Double Cropping Small Grains and Cotton

Thacker, G. W., Taylor, B. B. 02 1900 (has links)
No description available.
135

Double Row Spacing Planting Rate Trial

Stedman, Sam 02 1900 (has links)
No description available.
136

Objective Climatological Analysis of Extreme Weather Events in Arizona during the North American Monsoon

Mazon, Jeremy J., Castro, Christopher L., Adams, David K., Chang, Hsin-I, Carrillo, Carlos M., Brost, John J. 11 1900 (has links)
Almost one-half of the annual precipitation in the southwestern United States occurs during the North American monsoon (NAM). Given favorable synoptic-scale conditions, organized monsoon thunderstorms may affect relatively large geographic areas. Through an objective analysis of atmospheric reanalysis and observational data, the dominant synoptic patterns associated with NAM extreme events are determined for the period from 1993 to 2010. Thermodynamically favorable extreme-weather-event days are selected on the basis of atmospheric instability and precipitable water vapor from Tucson, Arizona, rawinsonde data. The atmospheric circulation patterns at 500 hPa associated with the extreme events are objectively characterized using principal component analysis. The first two dominant modes of 500-hPa geopotential-height anomalies of the severe-weather-event days correspond to type-I and type-II severe-weather-event patterns previously subjectively identified by Maddox et al. These patterns reflect a positioning of the monsoon ridge to the north and east or north and west, respectively, from its position in the "Four Corners" region during the period of the climatological maximum of monsoon precipitation from mid-July to mid-August. An hourly radar gauge precipitation product shows evidence of organized, westward-propagating convection in Arizona during the type-I and type-II severe weather events. This new methodological approach for objectively identifying severe weather events may be easily adapted to inform operational forecasting or analysis of gridded climate data.
137

Etude du déterminisme environnemental du cycle de reproduction chez la perche commune (Perca fluviatilis) / Study of environmental determinism of the reproductive cycle in Eurasian perch (Perca fluviatilis)

Abdulfatah, Abdulbaset 28 October 2010 (has links)
Cette thèse a déterminé les rôles respectifs de la photopériode et de la température lors des différentes et successives étapes du cycle de reproduction (induction du cycle, vernalisation, ponte) chez la perche commune Perca fluviatilis femelle. La photopériode est le facteur environnemental principal qui synchronise l’induction du cycle de reproduction chez la perche commune, la température joue uniquement un rôle modulateur. Une baisse importante de la durée de la photophase de 4-8 heures est recommandée. Le maintien d'une photopériode constante basée sur une photophase longue et constante (17L : 7D) inhibe l’induction, alors que le maintien d’une température élevée et constante (22-23°C) ne le permet pas. Pour la phase de vernalisation, une photopériode de type jour court (8L : 16D) est nécessaire. Concernant les effets de la température, une forte et progressive baisse de la température (de 22 à 6°C sur 16 semaines) est recommandée pour assurer un développement gonadique complet (ovocytes aux stades de vitellogenèse avancée en fin de phase d’induction et de la maturation finale avant la période de ponte). Des baisses de température plus modérées (de 22 à 14-18°C) altèrent la reproduction, notamment pendant la phase de vernalisation. L’augmentation finale de la température après la vernalisation est le facteur principal de synchronisation de la ponte. Cette étude a permis la mise au point d’un protocole photo-thermopériodique fiable garantissant des taux d’induction et de ponte très élevés, proches de 100%, chez les femelles / This PhD thesis has determined the respective roles of photoperiod and temperature at the different and successive steps of the reproductive cycle (induction of the cycle, wintering period, spawning) in female Eurasian perch Perca fluviatilis. Photoperiod is the main environmental factor which synchronizes the onset of the reproduction cycle in Eurasian perch female, temperature plays only a modulating role. A high photoperiod decrease of 4 or 8 hours is recommended. The maintenance of constant photoperiod based on a long photophase (17L: 7D) delays the onset of the reproductive cycle, whereas the maintenance of a warm and constant temperature (22-23°C) does not delay it. For the wintering period, a photoperiod with a short daylight period (8L : 16D) is required. Concerning the effect of temperature variations, a high and progressive temperature decrease (from 22 to 6°C over 16 weeks) is recommended to ensure a complete ovarian development (all oocytes achieved the advanced vitellogenesis stage at the end of the induction phase and and final maturation stage just before spawning). Slight temperature decreases (from 22 to 14-18°C) alter the reproduction, especially during the chilling period (wintering period). The final increase of temperature (up to 14°C) after the wintering period is the main factor for spawning synchronization. This study allowed the development of a reliable photo-thermal protocol for out-of-season spawning with very high rates (close to 100%) of female response and spawning
138

Effects of twice-over grazing on the nesting success of grassland songbirds in southwestern Manitoba

Carnochan, Stacey 21 September 2016 (has links)
Rotational grazing is being promoted by some land managers, government agencies, and conservation groups as superior to season-long grazing for improving pasture and cattle production, and for grassland bird conservation; however, the assumed benefits have not been comprehensively studied. In 2011 and 2012, I examined the effects of twice-over rotational grazing on the nesting success of grassland songbirds in southwestern Manitoba, Canada. I monitored nesting attempts and collected structural vegetation data for five species of obligate grassland bird (n=110) and one shrub-nesting species (n=41). Nesting analyses were conducted using logistic exposure models. Twice-over grazing had a significantly negative effect on the nesting success of the ground nesting species, including Savannah sparrows (Passerculus sandwichensis). Grazing system did not have an effect on vegetation structure. The results are consistent with other rotational grazing studies, and suggest that twice-over rotational grazing does not benefit grassland songbirds in mixed-grass prairie habitats. / October 2016
139

conceptual packaging

Raungpaka, Thirada 01 January 2006 (has links)
Packaging and package design is commonly thought of as a tool to attract the consumer to material goods. Packages, however, have other attributes. In Japan, packaging design is very charming because of the delicate selection of materials, images, and interaction. Different kinds of material provide different emotions and appeal to our sense of touch, which can be interpreted in many ways. Packaging lets us directly interact with an object and this experience becomes memorable and intimate. The combination of image and interaction creates another dimension of story telling. My creative project, Conceptual Packaging, is an experiment in using materials and forms to package immaterial concepts and messages such as memories.
140

Season of Birth and Risk for Schizophrenia

Roberts, Seth 05 December 2008 (has links)
Background: Schizophrenia is a chronic, debilitating mental disorder characterized by positive (e.g., hallucinations, delusions) and negative (e.g., catatonia, flat affect) signs and symptoms. Many studies suggest that individuals born in winter or spring months are at increased risk for schizophrenia. Study Objectives: 1) To determine whether season of birth affects risk for schizophrenia in the Irish Study of High Density Schizophrenia Families (ISHDSF). 2) To examine, by computer simulation, power to detect genetic associations with schizophrenia under a variety of conditions and using different analytic strategies. 3) To test whether specific genes are associated with schizophrenia in the Irish Case Control Schizophrenia Study (ICCSS), using different analytic strategies to account for season of birth. Methods: A case-control design was used to examine the relationship between schizophrenia and season of birth. Cases were individuals from the ISHDSF diagnosed with schizophrenia. Controls were the general population of Ireland, with data provided by Ireland’s Central Statistics Office (CSO). The birth frequencies for each month or quarter were compared in the two groups by a chi square test. Computer simulations were conducted to examine power to detect schizophrenia susceptibility loci using either all cases or only cases born in high-risk months, under different conditions and models for how genetic risk and season of birth interact to influence risk for schizophrenia. Data for six genetic markers from the ICCSS were analyzed for evidence of association, using all cases, and then using only cases born in high-risk months. Setting and Study Participants: ISHDSF families were ascertained through inpatient psychiatric care facilities serving >95% of the Irish population. Diagnoses were established using DSM-III-R criteria, and birthdates were recorded for all individuals. The Irish CSO provided aggregate, population-level data for number of births in Ireland by month for the years 1976-2000 and by quarter for the years 1900-2000. The ICCSS is a sample of schizophrenic and control individuals who have been genotyped at many loci across the genome. Schizophrenics were ascertained through in- and outpatient psychiatric facilities, had diagnoses verified by an expert, and their birthdates recorded. Controls were selected from several sources, e.g. blood donation centers, and denied any lifetime history of schizophrenia. For each subject in the ICCSS, all four grandparents were born in Ireland or the United Kingdom. Results: Number of births in each month was compared for schizophrenics in the ISHDSF and general population controls, resulting in a chi square of 19.44 (p value ~ 0.054, 11 df). Simulations revealed that, in some circumstances, power to detect genetic associations was increased by restricting cases to those born in high-risk months. Analysis of data from the ICCSS revealed that restricting cases to high-risk birth months increased the evidence for association for three of six markers tested, two of which were associated with the gene FBXL21. Conclusions: Birth in the months of March, April, or May appears to be associated with elevated risk for schizophrenia in the ISHDSF. In attempting to find susceptibility loci for schizophrenia, restricting genetic association analyses to schizophrenics born in high-risk months may result in increased power to detect genetic association in some circumstances.

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