<p>Extensive bedding plane exposures in the Ludlowville shales along Cazenovia Creek Near Spring Brook, New York display the spatial distribution of the skeletal remains from a marine faunal assemblage. Fossils typically occur in aggregates that are subcircular in plan view and plano-convex in cross-section with the convex side down. A previous paleoecological study of the most abundant brachiopod, Ambocoelia umbonata (Conrad), (Bray, 1969) revealed that aggregations were in-situ 'life' associations rather than mechanical accumulations of shell debris. This conclusion suggested that fossil clusters represent short-lived ecological successions or seres and the present study was undertaken to examine the origin, development, and extinction of clusters .</p> <p>Three clusters, sampled in 10 x 10 x 0.5 cm blocks, were subjected to an exhaustive analysis. The absence of sedimentary structures, lack of internal lamination, minor amounts of silt-size quartz, pelleted thin section textures, numerous burrow traces and presence of 3 species of deposit feeding nuculanid bivalves strongly suggested a bioturbated, fluid substratum. Under these conditions fossil clusters were initiated by attaclunent of spat to scattered shell surfaces (i.e. trilobite carapaces, cephalopod shells and rooted crinoids). Successful growth of sessile invertebrates (largely brachiopods) produced continuous addition of surface area for future spat attaclunent and clusters expanded laterally while the soft bottom prevented vertical buildup faster than sedimentation rates. Fossil density distributions within samples indicated that several species had a patchy arrangement within clusters and that the dispersion pattern of two taxa, .Ambocoelia and Styliolina, altered during cluster development. Analysis of associations by presence-absence criteria revealed that specimens larger than 2 mm had few taxonomic associations near the base of clusters and many associations near the top. The number of associated taxa among specimens smaller than 0.75 mm remained constant, but there was a decrease in the number of shared associations by some taxa toward the top of clusters. Species-abundance distributions indicated no temporal change in diversity and the succession within clusters apparently did not proceed by colonization of different taxa at different times. The lack of bottom currents and the reduction of bioturbation in shell laden patches resulted in fecal concentration that created a substrate which was locally lethal. This ultimately caused failure of spat recruitment and clusters were terminated over a short period of time. </p> / Thesis / Doctor of Philosophy (PhD)

<p> Globular clusters (GCs) can be divided into two subpopulations when plotted on a colour-magnitude diagram: one red and metal-rich (MR), and the other blue and metal-poor (MP). For each subpopulation, any correlation between colour and luminosity can then be converted into mass-metallicity relations (MMRs).</p> <p> Tracing the MMRs for fifteen GC systems (GCSs) - all around Brightest Cluster Galaxies - we see a nonzero trend for the MP subpopulation but not the MR. This trend is characterised by p in the relation Z=M^p. We find p ~ 0.35 for the MP GCs, and a relation for the MR GCs that is consistent with zero. When we look at how this trend varies with the host galaxy luminosity, we extend previous studies (e.g., Mieske et al, 2006b) into the bright end of the host galaxy sample.</p> <p> In addition to previously presented (B-I) photometry for eight GCSs obtained with ACS/WFC on the HST, we present seven more GCSs. Four of these are newly analysed from HST data, one is previously presented (g-i) photometry obtained with GMOS on Gemini South, and two are the author's newly reduced and analysed (g-i) photometry also obtained with GMOS on Gemini South.</p> <p> Interpretation of these results is important for further understanding the formation and evolution of galaxies within the hierarchical-merging picture, and what process enables the production of two subpopulations.</p> / Thesis / Master of Science (MSc)

This thesis presents deep photometry of the globular cluster system of the massive elliptical galaxy, M49. Using the C and T1 Washington filters from the MOSAIC camera on the Cerro Tololo Inter-American Observatory 4m telescope, we studied the color, metallicity and luminosity distributions of the globular cluster system. We find a strong bimodality in the color and metallicity distributions of the globular cluster system down to a magnitude of R <24, with 1718 clusters belonging to the blue population and 698 to the red population. In agreement with previous studies, the blue sequence does not exhibit a strong mass-metallicity relation. No difference is found in the mass-metallicity relation between the inner and outer clusters of M49. These results suggest that the mechanism responsible for the mass-metallicity re- lation is not local and may be affected by the galaxy’s individual dynamic history, location in the galaxy cluster and the formation of the globular cluster system itself. We suggest a mechanism based on accretion of gas by proto-clusters as they orbit within their parent dwarf galaxies. The latter would fit the observed behavior of the MMR. / Thesis / Master of Science (MSc)

<p> A series of chiral transition metal clusters of the type MCo2(CO)6C-CO2R, where M = Co(CO)3, (C5H5)Mo(CO)2, (i-Pr-C5H4)Mo(CO)2 or (indenyl)Mo(CO)2 and R =menthyl or exo-bornyl have been synthesized and characterized using FAB mass spectrometry and high field NMR techniques. The isopropyl Cp and the indenyl ligands served as NMR probes to detect the chirality created by the incorporation of the terpenoidal capping group.</p> <p> The tricobalt clusters were treated with the bidentate ligands arphos, Ph2AsCH2CH2PPh2 and diphos, Ph2PCH2CH2PPh2. Treatment with arphos yields a pair of diastereomers which are interconverted via the migration of the Ph2As terminus of the arphos ligand from one cobalt vertex to another. This fluxionality was monitored by variable-temperature 31P NMR spectroscopy. The diphos cluster is not a fluxional molecule. However, the Co(CO)2P vertices are diastereotopic and give two signals in the 31P NMR. Thus, diphos serves as a convenient probe for chirality. </p> <p> In the case where M = Co(CO)3 , the two remaining cobalt vertices are diatereotopic and are, in principle, not equally susceptible to attack by an incoming ligand. To test for chiral discrimination, these molecules have been treated with several different phosphines. If the reaction were to proceed with any degree of selectivity, the 31P NMR spectrum ought to show resonances of unequal intensity. Such results have been obtained when a bulky phosphine, such as tricyclohexylphosphine, has been employed.</p> / Thesis / Master of Science (MSc)

Indiana University-Purdue University Indianapolis (IUPUI) / Depression is a heterogeneous mental health condition, varying in presentation across individuals. A candidate etiology that may help account for this heterogeneity is the neurotrophin hypothesis of depression, which proposes that stress downregulates brain-derived neurotrophic factor (BDNF) expression, leading to aberrant neurogenesis and depression. This etiology may manifest in a distinct symptom profile that may be reflected in depressive symptoms or symptom clusters. The effect of psychological interventions on BDNF is not known. Additionally, it is not known if BDNF levels mediate intervention effects on depressive symptom clusters. Using data from the eIMPACT trial (NCT02458690, supported by R01 HL122245), I examined baseline associations of BDNF with depressive symptoms and depressive symptom clusters. Also, I examined if the modernized collaborative care intervention for depression (internet CBT, telephonic CBT, and select antidepressant medications) affected BDNF and if changes in BDNF mediated intervention effects on cognitive/affective and somatic depressive symptom clusters. 216 participants (primary care patients with depression and elevated cardiovascular disease risk ≥50 years from a safety net healthcare system) were randomized to 12 months of the eIMPACT intervention (n=107) or usual primary care for depression (primary care providers supported by embedded behavioral health clinicians and affiliated psychiatrists; n=109). Plasma BDNF was measured with commercial ELISA kits. Depressive symptoms were assessed by the PHQ-9 (M=15.1, SD=5.0) from which cognitive/affective and somatic subscale scores were computed. No significant baseline associations were observed between BDNF and individual depressive symptoms or depressive symptom clusters. The intervention did not improve BDNF over 12 months. Similarly, 12-month changes in BDNF were not associated with 12-month changes in PHQ-9 cognitive/affective or somatic subscale scores. However, the intervention significantly improved PHQ-9 cognitive/affective and somatic subscale scores over 12 months. 12-month changes in BDNF did not mediate the effect of the intervention on 12-month changes in the PHQ-9 subscale scores. These findings suggest that modernized collaborative care for depression does not improve BDNF. Modernized collaborative care does yield improvements in both cognitive/affective and somatic depressive symptom clusters, albeit not via changes in BDNF.

<p>Depression is a heterogeneous mental health condition, varying in presentation across individuals. A candidate etiology that may help account for this heterogeneity is the neurotrophin hypothesis of depression, which proposes that stress downregulates brain-derived neurotrophic factor (BDNF) expression, leading to aberrant neurogenesis and depression. This etiology may manifest in a distinct symptom profile that may be reflected in depressive symptoms or symptom clusters. The effect of psychological interventions on BDNF is not known. Additionally, it is not known if BDNF levels mediate intervention effects on depressive symptom clusters. Using data from the eIMPACT trial (NCT02458690, supported by R01 HL122245), I examined baseline associations of BDNF with depressive symptoms and depressive symptom clusters. Also, I examined if the modernized collaborative care intervention for depression (internet CBT, telephonic CBT, and select antidepressant medications) affected BDNF and if changes in BDNF mediated intervention effects on cognitive/affective and somatic depressive symptom clusters. 216 participants (primary care patients with depression and elevated cardiovascular disease risk ≥50 years from a safety net healthcare system) were randomized to 12 months of the eIMPACT intervention (<em>n</em>=107) or usual primary care for depression (primary care providers supported by embedded behavioral health clinicians and affiliated psychiatrists; <em>n</em>=109). Plasma BDNF was measured with commercial ELISA kits. Depressive symptoms were assessed by the PHQ-9 (<em>M</em>=15.1, <em>SD</em>=5.0) from which cognitive/affective and somatic subscale scores were computed. No significant baseline associations were observed between BDNF and individual depressive symptoms or depressive symptom clusters. The intervention did not improve BDNF over 12 months. Similarly, 12-month changes in BDNF were not associated with 12-month changes in PHQ-9 cognitive/affective or somatic subscale scores. However, the intervention significantly improved PHQ-9 cognitive/affective and somatic subscale scores over 12 months. 12-month changes in BDNF did not mediate the effect of the intervention on 12-month changes in the PHQ-9 subscale scores. These findings suggest that modernized collaborative care for depression does not improve BDNF. Modernized collaborative care does yield improvements in both cognitive/affective and somatic depressive symptom clusters, albeit not via changes in BDNF.</p>

Regional economic development strategies such as cluster-based development are becoming increasingly popular with policymakers. Yet, the role of government in cluster development and sustainability is not clearly understood. However, network governance theory provides an ideal framework to better understand this role. This research attempts to fill the gap between cluster theory and public administration by testing a political/institutional context model developed by Miller (2006) that attempts to explain the extent of cluster-based economic development policies considering the political/institutional context. A collective case study focusing on the shipbuilding cluster in Alabama, Louisiana, and Mississippi was conducted. A total of 24 in-depth interviews were completed with key informants from economic development organizations, government institutions, and the shipbuilding industry. The major findings of the study indicate that (1) civic entrepreneurs, tax structures, and elected officials are not correlated with the extent of cluster-based policies; (2) the traditionalistic political subculture in the region is a major limiting factor for the development of governance structures suitable for cluster-based economic development and upgrading; (3) participants were highly satisfied with workforce and infrastructure development policies while government activities and programs had the lowest satisfaction; (4) the findings of this study show no support for a clear factor policy grouping as argued by Porter; and (5) network governance theory provides an ideal framework to build governance structures focused on linkages and formal/informal relationships that are more suitable for cluster-based development ameliorating the effects of a traditionalistic political culture. The contributions of this study become more important because of recent threats to the shipbuilding cluster in the Gulf Coast. The ability of government to adapt and facilitate the development and upgrading of the cluster will prove critical for the overall economic and social vitality of the region.

No description available.

No description available.

No description available.