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Disc degeneration is a natural process and is widely prevalent. The severity of disc degeneration and the type of treatment varies from person to person. Fusion is a commonly chosen treatment option. However, clinical and biomechanical studies have shown that intervertebral discs adjacent to a fusion experience increased motion and higher stress which may lead to adjacent-segment disease. Cervical disc arthroplasty achieves similar decompression of the neural elements, but preserves the motion at the operated level and may potentially decrease the occurrence of adjacent segment degeneration. Computationally, a validated intact 3D finite element model of the cervical spine (C2-T1) was modified to simulate single (C5-C6) and bi-level (C5-C7) degeneration. The single level degenerative model was modified to simulate single level fusion and arthroplasty with the Bryan and Prestige LP artificial discs. The bi-level degenerative model was modified to simulate a bi-level fusion, bi-level arthroplasty with Bryan and Prestige LP discs and a disc replacement adjacent to fusion. An in-vitro biomechanical study was also conducted to address the effects of arthroplasty and fusion on the kinematics of the cervical spine. A total of 11 specimens (C2-T1) were divided into two groups (Bryan and Prestige LP). The specimens were tested in the following order; intact, single level TDR at C5-C6, bi-level TDR C5-C6-C7, fusion at C5-C6 and TDR at C6-C7 (Hybrid construct) and finally a bi-level fusion. The intact state was tested up to a moment of 2Nm. After surgical intervention, the specimens were loaded until the primary motion (C2-T1) matched the motion of intact state (hybrid control). In all cases; computational and experimental, an arthroplasty preserved motion at the implanted level and maintained normal motion at the nonoperative levels. A fusion, on the other hand, resulted in a significant decrease in motion at the fused level and an increase in motion at the un-fused levels. In the hybrid construct, the TDR adjacent to fusion preserved motion at that level, thus reducing the demand on the other levels. The computational models were used to analyze disc stresses at the adjacent levels and facet forces at the index and adjacent levels. The disc stresses followed the same trends as motion. Facet forces though, increased considerably at the index level following a TDR. There was a decrease in facet forces however at the adjacent levels. The adjacent level facet forces increased considerably with a fusion. The hybrid construct had adjacent level facet forces between the bi-level TDR and bi-level fusion models. To conclude, this study highlighted that cervical disc replacement with both the Bryan and Prestige LP discs not only preserved the motion at the operated level, but also maintained the normal motion at the adjacent levels. Under hybrid loading, the motion pattern of the spine with a TDR was closer to the intact motion pattern, as compared to the degenerative or fusion models. Also, in the presence of a pre-existing fusion, this study shows that an adjacent segment disc replacement is preferable to a second fusion.

We describe techniques for fast compression of time series and hierarchical indexing of compressed series based on the assignment of importance levels to the extrema of time series and their derivatives. We formalize the distance functions used in compression and retrieval techniques. We describe retrieval techinques that use the developed compression and indexing techniques for fast retreval of series from a database that match a given pattern.

Sleep is a highly conserved behavioral state whose regulation is still unclear. In this thesis I initially briefly introduce the known sleep circuitry and regulation in vertebrates, and why zebrafish is seen as a good model to study sleep-regulation. I describe the existing two-process model of sleep regulation, which posits that the two processes C (circadian) and S (homeostatic) control timing of sleep-wake behavior. I then study the role melatonin plays in the circadian regulation of sleep using zebrafish. Firstly, we find that the absence of melatonin results in a reduction of sleep at night, establishing that endogenous melatonin is required for sleep at night. Secondly, melatonin mutants show a reduction in sleep in animals with no functional behavioral rhythms suggesting that melatonin does not require intact circadian rhythms for its effect on sleep. Thirdly, melatonin mutants do not exhibit any changes in circadian rhythms, suggesting that the circadian clock does not require melatonin for its function. Fourthly, we find that in the absence of melatonin, there is no rhythmic expression of sleep, suggesting that melatonin is the output molecule of process C. Lastly, we describe a connection between adenosine signaling (output molecules of process S), and melatonin. Following this we proceed to study the role adenosine signaling plays in sleep-wake behavior. We find that firstly, adenosine receptor A1 and A2 are involved in sleep- wake behavior in zebrafish, based on agonist/antagonist behavioral results. Secondly, we find that several brain regions such as PACAP cells in the rostral midbrain, GABAergic cells in the forebrain and hindbrain, Dopamine and serotonin cells in the caudal hypothalamus and sox2 cells lining the hindbrain ventricle are activated in response to the A1 antagonist and VMAT positive cells are activated in response to the A2A agonist, suggesting these areas are involved in adenosine signaling in zebrafish. Thirdly, we find that knocking out the zebrafish adenosine receptors has no effect on sleep architecture. Lastly, we find that while the A1 agonist phenotype requires the zfAdora1a receptor, the antagonist and the A2A agonist behavioral phenotypes are not mediated by the zfAdora1a, zfAdora1b and zfAdoraA2Aa, zfAdora2Ab receptors respectively.

Jointed goatgrass (Aegilops cylindrica Host; 2n=4x=28; CCDD) is an agriculturally important species both as a weed and as a genetic resource for wheat (Triticum aestivum L.; 2n=6x=42; AABBDD) improvement. In order to better understand the evolution of this species, the diversity of Ae. cylindrica was evaluated along with its progenitors, Ae. markgrafii (Greuter) Hammer (2n=2x=14; CC) and Ae. tauschii Coss. (2n=2x=14; DD), using chloroplast and nuclear microsatellite markers. Ae. cylindrica had lower levels of plastome and nuclear diversity than its progenitors. The plastome diversity of Ae. cylindrica was lower than its nuclear diversity. Ae. cylindrica was found to have either C-or D-type plastomes, derived from Ae. markgrafii or Ae. tauschii, respectively, where the C-type plastome was found to occur at a lower frequency than the D-type plastome. The nuclear genomes of Ae. cylindrica accessions with C-or D-type plastome were found to be very closely related, suggesting a monotypic origin. Furthermore, analyses suggests that Ae. tauschii ssp. tauschii contributed its D genome and D-type plastome to Ae. cylindrica. Ae. cylindrica accessions collected near Van Lake in southeastern Turkey, an area where Ae. tauschii ssp. tauschii and Ae. markgrafii overlap, showed high allelic diversity and may represent the site where Ae. cylindrica formed. Population structure analyses suggested a lack of regional genetic structure in Ae. cylindrica and evidence of migration of Ae. cylindrica among various regions. Finally, Ae. cylindrica accessions in the USA were found to be closely related to accessions from at least three regions of its native range central Anatolia, central East Turkey and western Armenia, and Caucasia. Wheat and jointed goatgrass are closely related and both have the D-genome. These two species can hybridize and produce backcross derivatives under natural conditions, a situation that may allow gene flow between these two species. In order to better understand mating patterns between these two species, a total of 413 first-generation backcross (BC₁) seeds obtained from 127 wheat-jointed goatgrass F₁ hybrids, produced under natural conditions, were evaluated for their parentage using chloroplast and nuclear microsatellite markers. Of the 127 F₁ hybrids evaluated, 109 had jointed goatgrass as the female parent, while the remaining 18 F₁ plants had wheat as the female parent. Of the 413 BC₁ plants analyzed, 358 had wheat and 24 had jointed goatgrass as the recurrent male parent. The male parentage of 31 BC₁ plants could not be determined. Although the majority of hybrids were pollinated by wheat, backcrossing of hybrids to jointed goatgrass would enable gene flow from wheat to jointed goatgrass. Though the observed frequency of jointed goatgrass-backcrossed hybrids (F₁ X jointed goatgrass) was low under field conditions, their absolute number is dependent on frequency of hybrids, which in turn, depends on the density of jointed goatgrass in wheat fields. Therefore, the recommendations to control jointed goatgrass in wheat fields and adjacent areas and to plant jointed goatgrass free wheat seed should be followed in order to avoid gene flow from wheat to jointed goatgrass. / Graduation date: 2006

Cultivated meadowfoam (Limnanthes alba Benth.) is an annual oil seed crop native to southern Oregon. California and British Columbia. The genus Limnanthes is composed of nine species and divided into two sections, Inflexae and Reflexae. The seed oil of meadowfoam is a rich source of erucic acid and several novel very long-chain fatty acids (VLCs). The former has been linked to increased risk of heart disease. The safe limit of erucic acid for human consumption is up to 5% of total fatty acids. Because the erucic acid concentrations of wildtype lines typically range from 9 to 23% and low erucic acid variants have not been discovered, chemical mutagenesis was used to develop a mutant line (LE76) with greatly reduced erucic acid (3%). The phenotypic distributions of F��� progeny from crosses between wildtype and mutant lines were continuous and differed across genetic backgrounds. Quantitative trait loci (QTL) affecting erucic and dienoic acid were mapped using F���:��� progeny from a cross between LE76 and Wheeler (a wildtype line) and a simple sequence repeat (SSR) map spanning the meadowfoam genome. The domestication of meadowfoam was based on L. alba, belonging to section Inflexac. The secondary and tertiary gene pools have not been important to the domestication process and have not supplied diversity for meadowfoam breeding. With the objectives of introgressing genes from wild relatives and also producing cytoplasmic male sterile lines by inserting the nuclear genome of L. alba into wild cytoplasm, inter-sectional crosses involving L. alba and three subspecies of L. douglasii and intra-sectional crosses involving L. alba and two subspecies of L. floccosa were carried out. The isolation mechanisms involved in keeping species apart from each other were found to be different within and between sections. The study of partially fertile intra-sectional hybrids showed that the reduced pollen viability (30-33%) was not due to structural differences between the chromosomes of the two species, as normal meiotic behavior was observed in PMCs. The inter-sectional crosses were found to be incompatible and various abnormalities during pollen tube growth were observed. / Graduation date: 2002

Thesis (Ph.D.)--Pennsylvania State University, 2000. / Also available online through Penn State campus network only.

The validation of UV reactors is currently accomplished by biodosimetry, in which the reactor is treated as a "black-box" and hence cannot account for the dependence of the dose delivery on the complex hydrodynamics and the spatial variation in UV intensity. Alternative methods, such as fluorescent microspheres as non-biological surrogates and computational fluid dynamics (CFD) simulations, have been developed; however, each method has its shortcomings. In this study, a novel technique for the spatial and temporal assessment of the hydrodynamics and the UV dose delivered and the link between these two factors in a lab-scale UV reactor using three dimensional laser induced fluorescence (3DLIF) is developed. This tool can also be utilized for the optimization of UV reactors and to provide data for validation of CFD-based simulation techniques. Regions of optimization include areas around the UV lamp where short-circuiting occurred, a longer inlet approach section that enhances the performance of the reactor by reducing short circuiting paths and a longer outlet region to provide greater mixing. 3DLIF allows real time characterization of mixing and dose delivery in a single lamp UV reactor placed perpendicular to flow by capturing fluorescence images emitted from a laser dye, Rhodamine 6G, using a high speed CCD camera. In addition to three-dimensional mixing, the technique successfully visualized the two-dimensional, transient mixing behaviors such as the recirculation zone and the von Karman vortices and the fluence delivery within the reactor, which has not been possible with traditional tracer test techniques. Finally, a decomposition technique was applied to the flow and fluence delivery based concentration data to reveal similar structures that affect these phenomena. Based on this analysis, changing the flow in the reactor, i.e. the Reynolds number, will directly affect the fluence delivery.

En fallstudie har gjorts på innebandyföreningen Alunda IBF herrar för att besvara frågan hur målkongruens (målöverensstämmelse) skapas i idrottsföreningar. Strävandet efter målkongruens anses i litteraturen vara ett viktigt inslag för att skapa förutsättningar för en framgångsrik och konkurrenskraftig organisation. För att skapa en helhetsbild på hur målkongruens implementeras har intervjupersonerna bestått av personer i olika nivåer inom Alunda IBF:s organisation. Denna studie visar att Alunda IBF använder de åtgärder som har identifierats i teorin som viktiga komponenter för att skapa målkongruens. Det förefaller dock som att spelarna inte uppfattar detta på samma sätt som ledningen vill. Resultat indikerar även på att en idrottsmans personliga mål är att vinna matcher vilket inte bör kontrastera idrottsföreningens målsättningar. Det finns dock indikation på att spelarna även vill ha mer inflytande om hur målen ska uppfyllas och det räcker alltså inte att målen är kongruenta. Vidare indikerar resultatet på att Alunda IBF, förmodligen likt många idrottsföreningar i lägre divisioner, tvingas kämpa med flera externa faktorer som i sig gör att det blir svårt att tydliggöra föreningens målsättning.

Previous studies have shown that L-tryptophan treatment has been known to reduce blood pressure (BP) in hypertensive rats. L-tryptophan is converted to serotonin (5-HT), a potent vasoconstrictor agonist. The direct vascular effects of L-tryptophan, an essential amino acid, and the mechanism that contributes to the fall in BP have not been fully explored. The present study aims to examine the direct vascular responses to both D- and L- tryptophan using perfused mesenteric vascular bed, an ex-vivo preparation that represents the resistance function of circulation. Perfusion was maintained at a constant flow rate (5 mL/min) with Krebs buffer (pH 7.4, 37˚C) after isolation from 12 to 14 week old male Sprague-Dawley rats. The basal perfusion pressure (PP) (mean ± SEM) was 27 ± 3 mmHg. Inclusion of D- and L-isomers in the perfusion medium led to concentration-dependent increase in PP. While the maximal response (Emax) was similar, D-tryptophan (EC50: 0.25 ± 0.12* µmol; Emax: 128 ± 8 mmHg) was more potent (lower EC50 value; *p < 0.01) than L-tryptophan (EC50: 0.79 ± 0.30 µmol; Emax: 141 ± 7 mmHg). Inclusion of increasing concentrations (2, 5 and 10 nM) of the 5-HT2A selective antagonist, ketanserin, led to parallel right-ward shifts in the concentration-response curves to D- and L-tryptophan with restoration of their Emax. In contrast, the α1 selective agonist, methoxamine (30 µM), constricted preparations, both D- (IC50: 0.94 ± 0.30* µmol; Imax: 96 ± 2%) and L-tryptophan (IC50: 2.8 ± 1.0 µmol Imax: 88± 1%) evoked concentration-dependent vasodilatation, an effect that was resistant to blockade by either ketanserin or other 5-HT antagonists. Again, D-tryptophan was more potent than L-tryptophan in the presence of 5-HT antagonist (*p < 0.05). Neither the removal of endothelium nor incubation with selective inhibitors of dilatory mediators released from the endothelium, failed to alter the vasodilator responses to D- and L-tryptophan. In potassium chloride depolarized preparations, L-tryptophan evoked an additive vasoconstrictor response. The vasodilator responses to L-tryptophan persisted in the presence of glibenclamide, a KATP channel inhibitor, or tetraethyl ammonium, a BKCa channel inhibitor, or BaCl2, a Kir channel inhibitor, or ouabain, a Na+-K+-ATPase pump inhibitor. These data confirm that the essential amino acid, L-tryptophan, as well as its D-isomer, evoke a biphasic vasoconstrictor and vasodilator responses in the resistance type mesenteric vascular bed. While the vasoconstrictor responses are mediated by activation of vascular 5-HT receptors, the endothelium-independent vasodilator responses are not linked to activation of vascular 5-HT receptors, vascular potassium channels, Na+-K+-ATPase pump or via inhibition of voltage-operated Ca2+-channels. Plasma concentration of L-tryptophan is about 90 - 120 µM. The endothelium/5-HT independent direct vasodilator responses characterized here for the first time could account for the antihypertensive/ BP lowering effect of L-tryptophan reported earlier by other laboratories.