Aquaculture plays a critical role in alleviating demand pressures caused by increasing fish consumption and over-exploitation of fishery stocks. While aquatic foods are generally considered low-revenue generators in comparison to other protein-sources, aquaculture products help to support food security, income, and higher standards of living, particularly in developing countries. Decision makers, i.e. policy-makers and farmers, are challenged with the responsibility of planning and conducting aquaculture development in a sustainable way whereby social, environmental and economic goals are simultaneously satisfied. Existing studies that economically evaluate the industry for its current and historical performance, and future development scenarios are invaluable to sustainable planning, but have not been developed in Mexico. This dissertation is comprised of two essays applying Economics and Operations Research theory to regional economic planning for the sustainable development of shrimp farming in northwest Mexico. The analyses are carried out both at the micro (farm) and macro (industry planning and development) levels based on an unbalanced panel of shrimp semi-intensive farms containing primary-source information at pond level for the period 1994, 1996-1998. Using an input distance function approach, the first essay examines total factor productivity (TFP) and technical efficiency (TE) using both traditional (T) and environmentally-adjusted (EA) indicators. The reduction in TFP was determined to be due to a technological regression as reflected by increased input-intensive production technology resulting in an increase in undesirable outputs. The learning curve resulting from a shift from white shrimp to blue shrimp production species resulted in higher FCRs, water exchange and pollution emissions, despite increasing shrimp yields. In all years except 994, EA TE and EA TFP were lower than the traditional TE and TFP scores. TE and TFP had an opposite behavior than yields in this period of time. In order to improve the technological change (TC) component of TFP in light of stable TE scores, increased government assistance in disseminating technological know-how is necessary to improve TFP at a faster rate during the transition period. A sensitivity analysis also revealed the economic feasibility of the implementation of pollution abatement technology based on the calculated shadow price of N and P pollutants at USD $6.35/kg and $8.3/kg respectively. In the second essay, a multi-criteria decision making (MCDM) model was developed to evaluate the sustainable development of shrimp farming in the northwest region of Mexico (States of Sonora, Sinaloa and Nayarit) based on government objectives for aquaculture development in Mexico. Three possible production systems among two species were investigated. The optimal combination of new shrimp farms within 22,500 ha over a five-year period is determined. The planning objectives assumed in the MCDM model are maximization of employment (E), foreign exchange earnings (XG), and economic rent (ER), and total pollution (TOTALPOLL) minimization, subject to land availability and local market demand constraints. Under a preliminary evaluation of single objective optimization, XG and ER maximization produce similar results: USD $888.6 and $322.5 million in foreign exchange earnings and economic rent respectively, and the creation of 6,150 jobs. The MCDM model was implemented using Feasible Goals, which allows for the simultaneous graphical evaluation of decision maps arising from trade-offs among efficient solutions. When fully allocating the available land (22,500 ha), the multiobjective development of the shrimp farming industry produces 7,490 new jobs, ER and XG of USD $204.5 and $497.6 million respectively, with a total pollutant discharge of 2,000 tons. The multiple-criteria optimization strongly favors semi-intensive systems (93% of the total 466 new farms), producing 57,119 tons of shrimp by 2005. The sustainable development of the industry based on the assumptions of this analysis does not suggest intensification of systems. Rather, the results of the MCDM analysis support the claim that semi-intensive farms, which are more common in Mexico, promote sustainability. Based on the findings of each of the essays, it is suggested that production performance indicators are needed on a periodic basis for the evaluation of the shrimp industry of Mexico. Production performance measurements may better assist farmers in the decision-making for industry sustainability and growth. Moreover, direct determination of N and P discharges by farms are recommended in future studies as well as incorporating risk and employing longer time series.

The effects on image formation through a tilted interference filter in a converging beam are investigated and an adequate compensation procedure is established. A method that compensates for small-scale seeing distortions is also developed with the aim of co-aligning non-simultaneous solar images from different passbands. These techniques are applied to data acquired with a narrow tiltable filter at the Swedish 1-meter Solar Telescope. Tilting provides a way to scan the wing of the Ca II H line. The resulting images are used to map the temperature stratification and vertical temperature gradients in a solar active region containing a sunspot at a resolution approaching 0''10. The data are compared with hydro-dynamical quiet sun models and magneto-hydrodynamic models of plage. The comparison gives credence to the observational techniques, the analysis methods, and the simulations. Vertical temperature gradients are lower in magnetic structures than in non-magnetic. Line-of-sight velocities and magnetic field properties in the penumbra of the same sunspot are estimated using the CRISP imaging spectropolarimeter and straylight compensation adequate for the data. These reveal a pattern of upflows and downflows throughout the entire penumbra including the interior penumbra. A correlation with intensity positively identifies these flows as convective in origin. The vertical convective signatures are observed everywhere, but the horizontal Evershed flow is observed to be confined to areas of nearly horizontal magnetic field.  The relation between temperature gradient and total circular polarization in magnetically sensitive lines is investigated in different structures of the penumbra. Penumbral dark cores are prominent in total circular polarization and temperature gradient maps. These become longer and more contiguous with increasing height. Dark fibril structures over bright regions are observed in the Ca II H line core, above both the umbra and penumbra. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.</p>

The vegetation communities that existed in the semi-arid intermontane basins and gorges of Central Otago prior to human settlement ~750 years B.P. are poorly understood. This is because of a lack of fossil evidence and complex restructuring by anthropogenic factors, especially increased fire frequency, and more recently mammalian grazing. There is also little information regarding the effect of the lost fauna on maintaining and structuring presettlement communities, both in Central Otago and throughout the eastern South Island dryland zone. This study aims to provide a clearer understanding of the functioning of pre-settlement ecosystems in dryland Central Otago, particularly the role of the largest vertebrate herbivores, the moa (Aves: Dinornithiformes), and to explore the implications of the extinct fauna for land conservation management across New Zealand. Late Pleistocene and Holocene vegetation communities of the Central Otago lowlands were reconstructed from plant macrofossils, including seeds, leaves, and wood, excavated from rockshelter, cave, and swamp deposits throughout the region. The macrofossils represent three main vegetation types: late Pleistocene to mid (late?) Holocene basin floor wetland herb associations, Olearia-shrublands surrounding these wetlands, and mid to late Holocene open scrubland and woodland in gorges and on low altitude slopes, dominated by filiramulate Olearia, Coprosma, and Corokia, with abundant lianes (Muehlenbeckia spp. and Rubus spp.) and understorey herbs. Many native tree and shrub species that are presently widespread in the Central Otago lowlands were rare or absent prior to anthropogenic fires (e.g. Discaria toumatou, Kunzea ericoides, Leptospermum scoparium). Other tree and shrub species once present are now extinct in the region (e.g. Coprosma obconica, Plagianthus regius, Pseudopanax ferox). The loss of these indigenous woody vegetation communities was a major factor contributing to the extirpation of many small bird species, and undoubtedly also reptile and invertebrate species, from the region. Plant macrofossils from rockshelters included remains of bird nests, identifiable by desiccated feathers and eggshell amongst them. These macrofossils include the first described plant remains from the nests of moa, which were constructed from a shallow bed of twigs of locally available shrubs and lianes. Many of the twigs are 25-30 mm in length and show evidence of having been clipped by moa bills. Desiccated coprolites, mostly of moa, but also specimens attributed to Finsch�s duck (Chenonetta finschi) and red-crowned parakeet (Cyanoramphus novaezelandiae), were recovered from rockshelter excavations. Moa species associated with a sample of coprolites were identified using ancient DNA analysis, and plant macrofossils from these were examined, together with previously unexamined moa gizzard content samples excavated from mires in the eastern South Island dryland zone. The results indicate that, in addition to previously reported browsing, upland moa (Megalapteryx didinus) and heavy-footed moa (Pachyornis elephantopus) also functioned as grazers, and seeds in their coprolites are dominantly of low shrubs and ground-cover herbs. Of particular interest was the higher than expected frequency of seeds from the currently rare and threatened 'spring annual' herbs; Ceratocephala pungens and Myosurus minimus subsp. novae-zelandiae (Ranunculaceae), suggesting further research on potential ecological relationships between moa and these plants would be worthwhile. The results of this study have provided a baseline for future conservation and restoration projects in the Central Otago lowlands.

Copies of author's previously published articles inserted / Bibliography: leaves 219-226 / xvi, 22l leaves, [5] leaves of plates : ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Mawson Institute for Antarctic Research, 1990

The purpose of this thesis was to characterise the contribution that a specific molecule, CREB1, plays in the many facets of a developing addiction phenotype. Indeed, CREB1 is known to contribute to long term learning and memory, and present an altered activation profile upon exposure to reinforcing substances, in brain regions implicated in addiction. Together, these observations provide a prima facie driver to investigate the specific involvement of CREB1 in brain regions implicated in reinforcement and drug-seeking. / Initially, I investigated Sprague Dawley rats whom had undergone behavioural sensitization to the repeated administration of the psychostimulant d-Amphetamine. Detailed in Chapter 3, the aims of this study were to determine the impact that environmental drug-context associations and psychostimulant sensitization makes upon expression of the activated or phosphorylated form of CREB1 (pCREB1). The data presented in the study reveals that many brain nuclei relevant to the behavioural effects of drug exposure show expression of pCREB1 subsequent to enduring amphetamine abuse, as well as upon return to an environment previously paired with amphetamine. The profile of pCREB1 expression within brains was unique to each pattern of drug dosing and context exposure, suggesting that unique sub-circuits underlie these different behavioural repertoires. / Using the impetus from this study, I determined to further investigate the contribution of CREB1 from specific brain regions, and the impact of its deletion upon behaviours characteristic of addiction. Indeed, the aims of this section of the project were to firstly employ relevant detection systems and current genetic-engineering technologies in creating appropriate expression animal lines, emphasising reward and reinforcement pathways. In addition, I aimed to understand the signalling systems and pathways which are activated by neurotransmitters, culminating in the phosphorylation of CREB and subsequently altered gene expression and long-term cellular and neuronal adaptation, induced by ongoing exposure to drugs of abuse. / Detailed in Chapter 4, I created a novel mutant mouse which was deficient in CREB1 within the dorsal telencephalon. Mice 'floxed' for the Creb1 gene expressed loxP DNA sequence around an exon critical to CREB1 function. These mice were interbred with mice expressing the enzyme Cre recombinase in dorsal telencephalic brain regions. Thus, mice expressing Cre recombinase and floxed for Creb1 demonstrated the deletion of CREB1 protein in these brain regions, which is demonstrated through experiments presented in Chapter 4. / Further in vitro characterisation of this mutant mouse was carried out and presented in Chapter 5. As CREB1 is important in synaptic plasticity and growth, it was necessary to evaluate any impact upon ontogeny through stereological analysis of cell number and volume, for relevant brain nuclei. The experiments demonstrate that mutant CREB1 mice were no different to control mice, however, it was possible that this lack of phenotype was partly contributed though changes in the level of other CREB/ATF-1/CREM bZIP family members. To this end, I determined to assay for transcript changes in these and related genes, finding confirmation of the deletion of the Creb1 transcript in the cortex and hippocampus, whilst observing a concomitant increase in Crem transcript. These data suggested that compensatory changes in brain regions receiving a recombination of Creb1 were apparent, contributing to the lack of an obvious phenotype in these mice. / Having confirmed the specific deletion of CREB1 in the appropriate brain nuclei, I then moved to examine the impact of the deletion behaviourally, both in terms of general ethology, and in regard to drug-induced phenotypes. Presented in Chapter 6, experiments assaying general ethology of the CREB1 mutant revealed a spontaneous hypoactivity when placed in a small open field environment. As CREB1 is involved in neural plasticity, I wished to assay for the impact on behavioural sensitization, a paradigm which reveals long-lived neural change. Experiments to this effect showed no perturbation of behavioural sensitization to the effects of cocaine in the mutant. In addition, mutant mice also showed a similar response to the rewarding effects cocaine as witnessed in the control mice, however, the CREB1 mutants demonstrated a perturbed drug-environment contextual memory, which was not retained in long-term place preference experiments. Operant conditioning studies for intravenous self administration of cocaine revealed that CREB1 mutants displayed a dose-specific diminished drive to self-administer cocaine, whereas in contrast, self administration of a natural reward was no different to control mice. These data suggest that there is a specific role for CREB1 in telencephalic glutamatergic neurons regulating the motivational and associative properties of cocaine. / Together, these data provide evidence that CREB1 functions as a key molecular substrate in long lived drug-context environment associations and neural change underlying the developing addicted state, warranting future investigation for its properties in producing drug related functional and behavioural change.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 6 uppsatser.

Thesis (Ph. D., Arid Lands Resource Sciences)--University of Arizona, 1983. / Includes bibliographical references (leaves 218-232).

Thesis (M.S.)--Ohio University, August, 2006. / Title from PDF t.p. Includes bibliographical references.

Thesis (Ph.D. in Biochemistry & Molecular Genetics) -- University of Colorado at Denver and Health Sciences Center, 2006. / Typescript. Includes bibliographical references (leaves 119-131). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 5 uppsatser.