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Showing 1 to 15 of 15 for “"parthenogenesis"”.
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Spatial and Temporal Genetic Heterogeneity in a Natural Daphnia Population: Ecological and Physiological Differences Between Genotypes (Cladocera, Freshwater, Parthenogenesis)
A three and one-half year study of spatial and temporal genetic heterogeneity in a population of the cyclically, parthenogenetic cladoceran, Daphnia pulex, inhabiting a permanent farm pond in east-central Illinois, indicated that electrophoretically distinct genotypes (clones) are frequently …
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Safer without Sex?
… usually produce haploid males by arrhenotokous parthenogenesis, both in the queenright and queenless condition. In the phylogenetically primitive subfamily Ponerinae reproductive caste dimorphism is much less pronounced: Ovarian morphology is rather similar in queens and workers, which …
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Reproductive Genomics in the Stick Insect Clitarchus hookeri
… to the foliage of the plant on which they feed. Parthenogenesis is common among these insects, with 10% of the taxa scattered in different families being completely or partially parthenogenetic. These insects are poorly studied at the molecular level compared with other insects that are of …
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Studies on the natural history of the limpets of the family Acmaedae
… The work on homing in Acmaea persona, artificial parthenogenesis in the eggs of Acmaea pelta, and artifical insemination of the eggs of Acmaea pelta was carried on at the Pacific Marine Station, Dillon Beach, California at 38° 14' 30" N. latitude, 122&176; 58' 30" W. longitude during the summer of …
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The plasma corticosteroids: their determination and normal variations
… (1955), a gland which has been implicated in the parthenogenesis of diabetes (Hoet and Lukens, 195; Jackson, 1955), hypertension (Sepeika, 1948, 1955), pre-eclampsia, and atherosclerosis, and which profoundly effects so many of the metabolic processes of the body. The need for accurate measurement …
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DNA methylation in the early porcine embryo
… produced by using in vitro techniques such as parthenogenesis, NT, and in vitro fertilization. Specifically, the methylation events that occur in the development of parthenogenetic and nuclear transfer blastocysts are more similar to the in vivo-produced blastocysts than the methylation …
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Bioinformatics and Next Generation Sequencing: Applications of Arthropod Genomes
… reveals herbivorous pest adaptations and parthenogenesis; (3) the complete genomic analysis of parasitoid wasp Copidosoma floridanum indicates the mechanism of polyembryony of such primary parasite of moths. By bioinformatics and genomics approaches, my study provides the genomic basis and …
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Evolution of reproductive mode in the scaly-winged bark louse Echmepteryx hageni
… co-existence of reproductive mode is geographic parthenogenesis. This pattern is characterized by sexual populations occupying the central part of the species’ range, while asexual populations are found in peripheral or marginal habitats. There is an alternative pattern of sexual-asexual …
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The Prevalence and Effect of Wolbachia Infection on the Brown Widow Spider (Latrodectus Geometricus)
… (e.g., male-killing, feminization, induced parthenogenesis, nutrient acquisition, etc.). As this symbiont has not previously been found in the genus <em>Latrodectus</em>, the consequences on the spider’s life history patterns are unknown. In the 2<sup>nd</sup> chapter, I examine the effects …
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Distribution of chemistry and sexual fecundity in the lichenized-fungi, Xanthoparmelia cumberlandia and Xanthoparmelia coloradoensis on Boulder Mountain, Aquarius Plateau, UT
<p>Three aspects of <em>Xanthoparmelia cumberlandia</em> and <em>Xanthoparmelia coloradoënsis</em> populations found at two elevations are explored: clustering of secondary chemicals and the resulting implications for taxonomic distinctions, the usefulness of thallus size as an indirect measure of …
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Molekulargenetische und zytogenetische Untersuchungen zur paternalen Introgression beim gynogenetischen Amazonenkärpfling, Poecilia formosa
Die Frage nach der Entstehung und Beibehaltung von sexueller Reproduktion nimmt in der Biologie eine zentrale Stellung ein. Dazu werden seit langem die Vor- und Nachteile asexueller Fortpflanzung diskutiert, da man sich von einer vergleichenden Betrachtungsweise wichtige Aufschlüsse erwartet. Dem …
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Optimization of Control Source and Error Sensor Locations in Free Field Active Noise Control
<p>Previous work has shown that active noise control (ANC) can be applied to axial cooling fans. Optimization of the control source and error sensor placement is desired to maximize the attenuation using ANC. A genetic algorithm was developed to find the optimal placement of control sources for a …