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Full-Text Articles in Life Sciences

Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan Dec 2022

Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan

Doctoral Dissertations

Understanding the shape variation of the human sphenoidal sinus is important to several areas of research. This includes clinical investigation (sinus pathology and safe endoscopic endonasal surgical practice) and paranasal sinus evolution (for which there is still no consensus). Yet, the sphenoidal sinus has high morphological variation, prohibiting its quantification through traditional geometric morphometric landmarking methods. The sphenoid body, and thus also the sinus contained within, is located directly at the developmental center of the basicranium in humans, where the three cranial fossae meet at the midline, and adjacent to the three synchondroses which are the sites of cranial base …


Morphological And Gene Expression Plasticity In Neotropical Cichlid Fishes, Sharon Fern Clemmensen Dec 2017

Morphological And Gene Expression Plasticity In Neotropical Cichlid Fishes, Sharon Fern Clemmensen

Doctoral Dissertations

Trophic divergence in cichlid fish is linked to morphological shifts in the pharyngeal jaw apparatus. For instance, in the Heroine cichlids of Central America, the ability to crush hard-shelled mollusks is a convergent phenotype with multiple evolutionary origins. These durophagous species often have very similar pharyngeal jaw morphologies associated with the pharyngeal jaw apparatus and some of these similarities could be due to phenotypically plastic responses to mechanical stress. I examined the durophagous cichlid Vieja maculicauda for differences in pharyngeal osteology, dentition, and soft tissues when exposed to different diet regimes. Here I discuss the effect on the morphology and …


A Molecular And Morphological Investigation Of The Springtail Genus Orchesella (Collembola: Entomobryomorpha: Entomobryidae), Catherine Louise Smith May 2015

A Molecular And Morphological Investigation Of The Springtail Genus Orchesella (Collembola: Entomobryomorpha: Entomobryidae), Catherine Louise Smith

Masters Theses

Chapter 1 is devoted to a molecular overview of the North American members of the springtail genus Orchesella using mitochondrial and nuclear DNA. Both genes strongly support the presence of four major clades within Orchesella. Chapter 2 is a morphological revision of the species near Orchesella celsa Christiansen & Bellinger. Five new species are described based largely on chaetotaxonomical differences in. Chapter 3 is an investigation into the origins of United States populations of two introduced European members of the genus, Orchesella cincta Linnaeus and Orchesella villosa Linnaeus. Mitochondrial data between populations from the two continents indicates multiple introductions for …


Synthesis, Characterization And Self-Assembly Of Amphiphilic Block Copolymers, Xiaojun Wang May 2012

Synthesis, Characterization And Self-Assembly Of Amphiphilic Block Copolymers, Xiaojun Wang

Doctoral Dissertations

This dissertation presents a review on state-of-the-art research of well-defined charged block copolymers, including synthesis, characterization, bulk morphology and self-assembly in aqueous solution of amphiphilic block polyelectrolytes. In Chapter 1, as a general introduction, experimental observations and theoretical calculations devoted towards understanding morphological behavior in charged block copolymer systems are reviewed along with some of the new emerging research directions. Further investigation of charged systems is urged in order to fully understand their morphological behavior and to directly target structures for the tremendous potential in technological applications. Following this background, in Chapters 2, 3, 4 and 5 are presented the …