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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

1982 Harvest-Aid Chemical Research at Yuma

Carasso, F. M., Briggs, R. E. 02 1900 (has links)
No description available.
112

Sweetpotato Whitefly, Bemisia tabaci, 1982 Research Results

Butler, G. D. Jr., Henneberry, T. J. 02 1900 (has links)
No description available.
113

Cotton Harvest-Aid Chemicals

Taylor, B. B., Briggs, R. E. 02 1900 (has links)
No description available.
114

Effects of Planting Date on Cotton Lint Yield

Kittock, D. L., Taylor, B. B. 02 1900 (has links)
No description available.
115

Gender Differences in Narrative Descriptions of Date Rape

Wade, John Charles 08 1900 (has links)
This study was conducted to examine the experience of unwanted sexual aggression from both the male and female perspectives. Questionnaires were distributed to 325 students, and of these, 142 wrote free-response narratives describing their most sexually aggressive experience. Two raters scored and analyzed the narratives on the basis of 19 categories for male responses and 16 categories for female responses. Differences between the male and female perception of the experience of unwanted sexual aggression were found on several categories. The results of this study suggest that date rape awareness and prevention programs should emphasize the point that dating and sexual encounters can easily be fraught with miscommunication and misinterpretation, and encourage clearer communication and better understanding.
116

Sur les origines, l'histoire évolutive et biogéographique du palmier-dattier (Phoenix dactylifera L.) : l'apport de la génétique et de la morphométrie / Origins, evolutionary and biogeographical history of the date palm (Phoenix dactylifera L.) : the contribution of genetics and morphometrics

Gros-Balthazard, Muriel 20 December 2012 (has links)
Les objectifs de ce travail visent à appréhender l'histoire évolutive et biogéographique du palmier dattier (Phoenix dactylifera L.), espèce d'une importance capitale pour les populations humaines des régions chaudes et arides d'Afrique du Nord et du Moyen-Orient, au moyen d'analyses génétiques et morphométriques. En effet, les origines de la domestication du dattier demeurent peu connues malgré les données archéologiques qui semblent attester de sa culture à partir de la fin du 4ème millénaire avant notre ère. L'analyse phylogénétique du genre Phoenix réalisée à partir de séquences chloroplastiques a permis d'identifier les parents proches du dattier. Des populations de dattiers sauvages sont reconnues pour la première fois grâce à des analyses de diversité et de structuration génétiques. De manière congruente, l'analyse morphométrique de contours de la graines s'appuyant sur la méthode des transformées elliptiques de Fourier met en évidence une nette différenciation entre les individus sauvages et cultivés. La caractérisation des changements de traits morphologiques de la graine liés à la domestication est exploitée pour définir le statut sauvage ou domestiqué de matériel mis au jour dans différents sites archéologiques du Pakistan et d'Egypte. En outre, l'étude génétique de dattiers d'origine diverses semble démontrer qu'au moins deux évènements de domestication ont eu lieu : l'un en Afrique et l'autre au Moyen-Orient. Finalement, les études génétiques et morphométriques, menées séparément ou conjointement selon le type et l'ancienneté du matériel analysé, permettent pour la première fois de discuter des origines, de l'histoire biogéographique et de la dynamique de l'agrobiodiversité du palmier dattier, dans le temps et dans l'espace. / The objectives of this work are to understand the evolutionary history and biogeography of the date palm (Phoenix dactylifera L.), a species of importance to human populations in hot, arid regions of North Africa and the Middle East using genetic and morphometric analyzes. Indeed, the origins of the domestication of the date palm remain poorly understood despite the archaeological data that seem to attest its culture from the late 4th millennium BCE.Phylogenetic analysis of the genus Phoenix made ​​from chloroplast sequences identified close relatives of the date palm. Populations of wild date palms are recognized for the first time through analyses of genetic diversity and structure. Congruently, morphometric analysis of the seed outline based on the method of elliptic Fourier transform highlights a clear differentiation between wild and cultivated individuals. Characterization of changes in seed morphological traits related to domestication is used to define the status of wild or domesticated material excavated from various archaeological sites in Pakistan and Egypt. In addition, the date palm genetic study of various origins seems to indicate that at least two domestication events took place: one in Africa and one in the Middle East. Finally, genetic and morphometric studies, conducted separately or together depending on the type and age of the material analyzed, allow for the first time to discuss the origins, history and biogeographic dynamics of date palm agrobiodiversity, in time and space.
117

Automatic assessment of biological control effectiveness of the egg parasitoid Trichogramma bourarachar against Cadra cautella using machine vision

Song, Yuqi January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Naiqian Zhang / The primary objective of this research is to achieve automatic evaluation of the efficiency of using Trichogramma bourarachae for biological control of Cadra (=Ephestia) cautella by calculating the rate of parasitization. Cadra cautella is a moth feeding as a larva on dried fruit as well as stored nuts, seeds, and other warehouse foodstuffs. It attacks dates from ripening stages while on tree, throughout storage, and until consumption. These attacks cause significant qualitative and quantitative damages, which negatively affect dates’ marketability, resulting in economic losses. To achieve this research goal, tasks were accomplished by developing image processing algorithms for detecting, identifying, and differentiating between three Cadra cautella egg categories based on the success of Trichogramma parasitization against them. The egg categories were parasitized (black and dark red), fertile (unhatched yellow), and hatched (white) eggs. Color, intensity, and shape information was obtained from digital images of Cadra eggs after they were subjected to Trichogramma parasitization and used to develop detection algorithms. Two image processing methods were developed. The first method included segmentation and extractions of color and morphological features followed by watershed delineation, and is referred to as the "Watershed Method" (WT). The second method utilized the Hough Transformation to find circular objects followed by convolution filtering, and is referred to as the "Hough Transform Method" (HT). The algorithms were developed based on 2 images and then tested on more than 40 images. The WT and the HT methods achieved correct classification rates (CCRs) of parasitized eggs of 92% and 96%, respectively. Their CCRs of yellow eggs were 48% and 94%, respectively, while for white eggs the CCRs were 42% and 73%. Both methods performed satisfactorily in detecting the parasitized eggs, but the HT outperformed the WT in detecting the unparasitized eggs. The developed detection methods will enable automatic evaluation of biological control of Cadra (=Ephestia) cautella using Trichogramma bourarachae. Moreover, with few adjustments these methods can be used in similar applications such as detecting plant diseases in terms of presence of insects or their eggs.
118

From Blockhouse To Hog House: The Historical Dendroarchaeology Of The Swaggerty Blockhouse, Cocke County, Tennessee, U.S.A.

Mann, David F., Grissino-Mayer, Henri D., Faulkner, Charles H., Rehder, John B. 01 1900 (has links)
The Swaggerty Blockhouse has historical and cultural significance for Tennessee because it is believed to be the only remaining 18th Century blockhouse in the state. We incorporated analyses of artifacts obtained from archaeological excavations coupled with tree-ring dating techniques to determine the possible year of construction of the structure. A nearby reference tree-ring chronology from Norris Dam anchored the Swaggerty Blockhouse tree-ring chronology from 1674 to 1859. The assemblages of artifacts (nails, ceramics, and window glass) recovered from the site corroborated the construction date and provided a clear understanding of the structure’s use as a barn for storage and hog processing. Based on our analyses, the historic Swaggerty ‘‘Blockhouse,’’ originally believed to have been built by James Swaggerty in 1787, is instead a small cantilever barn built by Jacob Stephens in 1860 and used for hog farming.
119

Modelos de regressão log-gama generalizado com fração de cura / The generalized log-gama mixture model with covariates

Rizzato, Fernanda Bührer 08 February 2007 (has links)
Neste trabalho considera-se uma reparametrização no modelo log-gama generalizado para a inclusão de dados com sobreviventes de longa duração. Os modelos tentam estimar separadamente os efeitos das covariáveis na aceleração ou desaceleração no tempo e na fração de sobreviventes que é a proporção da população para o qual o evento não ocorre. A função logística é usada para o modelo de regressão com fração de cura. Os parâmetros do modelo, serão estimados através do método de máxima verossimilhança. Alguns métodos de influência, como a influência local e a influência local total de um indivíduo, serão introduzidos, calculados, analisados e discutidos. Finalmente, um conjunto de dados médicos será analisado sob o modelo log-gama generalizado com fração de cura. Uma análise de resíduos será executada para verificar a qualidade de ajuste do modelo. / In this work the generalized log-gama model is modified for possibility that long-term survivors are present in the data . The models attempt to estimate separately the effects of covariates on the accelaration/decelaration of the timing of a given event and surviving fraction; that is, the proportion of the population for which the event never occurs. The logistic function is used for the regression model of the surviving fraction. Inference for the model parameters is considered via maximum likelihood. Some influence methods, such as the local influence, total local influence of an individual are derived, analyzed and discussed. Finally, a data set from the medical area is analyzed under log-gama generalized mixture model. A residual analysis is performed in order to select an appropriate model.
120

Utilisation de la cryoconservation pour la conservation et la production de cultures in vitro de palmier dattier (Phoenix dactylifera L.) : Impact d'un protocole de cryoconservation sur la physiologie des cals embryogènes de palmier dattier / Use of cryopreservation for the conservation and production of date palm (Phoenix dactylifera L.) in vitro cultures : Impact of a cryopreservation protocol on the physiology of embryogenic callus of date palm

Salma, Mohammad 08 December 2015 (has links)
Le palmier dattier (Phoenix dactylifera L.) a une grande importance écologique et socio-économique dans les zones arides et semi-arides du globe. Cette espèce présente une grande diversité (plus de 2.000 variétés identifiées) qui est menacée par la production à grande échelle de variétés élites. Il est nécessaire de développer des techniques permettant de conserver cette diversité et de gérer la production des variétés élites multipliées in vitro. La cryoconservation (azote liquide, -196°C) est la seule technique disponible à l’heure actuelle permettant la conservation à long terme, à coûts réduits et en sécurité de cette diversité. Dans ce travail, nous avons comparé l’efficacité de deux techniques de cryoconservation, la vitrification en goutte (DV) et la D cryo-plate (DP), pour la cryoconservation de masses proembryogènes (PEM) de deux variétés de palmier dattier, Sokary et Sultany. Avec la DV, la survie des PEM cryoconservées est nulle sans prétraitement au saccharose (3 jours avec 0,5M) et sans traitement avec la solution de vitrification PVS2. Après 15 à 120 min de traitement avec PVS2, la survie est comprise entre 90,9-98,6% et 85,6-88,0%, respectivement pour Sokary et Sultany. Avec un prétraitement au saccharose, 21,1% des PEM de la variété Sokary survivent à la cryoconservation sans traitement avec PVS2. Avec la DP, un effet positif du prétraitement au saccharose est observé sur la survie des PEM cryoconservés. Pour Sokary, la survie la plus importante (de 92,0 à 95,8%) après congélation est obtenue pour des durées de dessiccation comprises entre 60 et 120 min. La survie après cryoconservation est comprise entre 67,0 et 74,6% après des durées de 90 à 120 min de dessiccation pour Sultany. Avec les deux techniques expérimentées, l'intensité de croissance des PEM cryoconservées est supérieure chez Sokary par rapport à Sultany. L’étude histologique réalisée montre qu’en l’absence de prétraitement, c'est le traitement de loading qui induit la plasmolyse des cellules la plus importante, d'environ 26, 40 et 50%, respectivement pour les cellules méristématiques, les cellules embryogènes de la population I (PopI) et de la population II (PopII) par rapport à leur état initial. Le prétraitement au saccharose induit une plasmolyse d'environ 50% uniquement chez les cellules de PopII. Le traitement de loading et de vitrification n'entraîne pas de plasmolyse supplémentaire. Aucune plasmolyse n'est observée chez les cellules méristématiques et les cellules de PopI. En revanche, les mesures de la surface de l'ensemble des cellules montrent chez les cellules méristématiques une diminution significative de surface après le prétraitement au saccharose, mais aucune différence significative après le traitement de loading et de vitrification. Chez les cellules embryogènes de PopI, une diminution supplémentaire de la surface est observée après le traitement de vitrification. L’étude de la circularité des noyaux montre une déformation permanente des noyaux des cellules non prétraitées des trois types cellulaires, alors que seuls les noyaux des cellules de PopII présentent cet aspect chez les PEM prétraitées. Enfin, l'étude du degré de méthylation des PEM par immunolocalisation conclut à l'absence de différences significatives entre les PEM témoins non traitées et les autres conditions expérimentales. Cependant, les tissus différenciés présentent un pourcentage de noyaux méthylés plus important par rapport aux cellules embryogènes et aucun marquage n'est noté chez les cellules méristématiques. Nos résultats ont permis de préciser l’effet de la cryoconservation sur l’intégrité structurale et la physiologie des PEM de palmier dattier. Ils contribuent également à la sauvegarde de la biodiversité du palmier dattier. / The date palm (Phoenix dactylifera. L) has a great ecological and socioeconomic importance in arid and semi-arid areas of the globe. This species displays a great diversity, with over 2,000 identified varieties, which is threatened by the large scale production of elite varieties. It is necessary to develop techniques allowing to conserve this biodiversity and to manage the production of in vitro propagated elite varieties. Cryopreservation (liquid nitrogen [LN], -196°C) is currently the only technique available ensuring the safe and cost-effective long-term conservation of this diversity. In this work, we compared the efficiency of two cryopreservation techniques, droplet-vitrification (DV) and D cryo-plate (DP), for the cryopreservation of proembryonic masses (PEMs) of two varieties of date palm, Sokary and Sultany. With DV, recovery of cryopreserved PEMs was nil without sucrose pretreatment (3 days, 0.5 M) and without treatment with PVS2 vitrification solution. After 15 to 120 min of PVS2 treatment, recovery was between 90.9-98.6% and 85.6-88.0% for Sokary and Sultany, respectively. Sucrose pretreatment led to 21.1% recovery of cryopreserved PEMs of variety Sokary without PVS2 treatment. Regrowth intensity of PEMs cryopreserved was generally lower in the Sultany variety compared to the Sokary variety. With DP, a positive effect of sucrose pretreatment on recovery of cryopreserved PEMs was observed. For Sokary, the highest recovery of PEMs (92.0 to 95.8%) after LN exposure was achieved for desiccation periods between 60 and 120 min. Recovery of cryopreserved PEMs of variety Sultany was between 67.0 and 74.6% after desiccation periods between 90-120 min. With DP, the regrowth intensity of cryopreserved PEMs was higher for variety Sokary compared to Sultany. The histological study performed showed that in absence of pretreatment, it was the loading treatment which induced the highest cell plasmolysis, with values of 26, 40 and 50% for meristematic, embryogenic PopI and PopII cells, respectively, compared to their initial state. Sucrose pretreatment induced a 50% plasmolysis only in PopII cells. The loading and vitrification treatments did not cause any additional plasmolysis. No plasmolysis was observed in meristematic or PopI cells. By contrast, the measurement of the surface of all cells revealed a significant decrease in the surface of meristematic cells after pretreatment, but no significant difference after the loading or vitrification treatments. In embryogenic PopI cells, an additional decrease in the cell surface was observed after the PVS2 treatment. The study of nuclei circularity showed a permanent deformation of nuclei of non-pretreated cells of the three cell types. In pretreated PEMs, only the nuclei of PopII cells displayed deformation. Finally, the study of the methylation degree in PEMs by immunolocalization revealed the absence of significant differences between the untreated controls and other experimental conditions. However, the differentiated tissues exhibited a higher percentage of methylated nuclei compared to embryogenic cells, while no stained nuclei were observed in meristematic cells. Our results allowed clarifying the effect of cryopreservation on the structural integrity and on the physiology of date palm PEMs. They also contribute to safeguarding of date palm biodiversity.

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