Rozprawy doktorskie na temat „Sea squirt”

This thesis describes the chemical investigations of several ascidian species collected from the Great Barrier Reef, Queensland, Australia. The thesis is divided into two separate components, Part A focuses on the isolation and structure elucidation of 11 previously undescribed ascidian metabolites. All structures were assigned using a combination of spectroscopic and/or chemical methods. Part B relates to the isolation and chemical conversion of a natural product to a combinatorial template. The natural product template was subsequently used in the generation of a solution-phase combinatorial chemistry library. A further two combinatorial libraries were generated from a synthesised model compound that was related to the natural product template. Part A. Investigation of Aplidium longithorax collected from the Swains Reefs resulted in the isolation of two new para-substituted cyclofarnesylated quinone derived compounds, longithorones J (30) and K (31). The former compound had its absolute stereochemistry determined by the advanced Mosher method. From an Aplidium longithorax collected from Heron Island, two new cyclofarnesylated hydroquinone compounds, longithorols C (46) and D (47) and a novel macrocyclic chromenol, longithorol E (48) were isolated. Longithorol C (46) had its absolute stereochemistry determined by the advanced Mosher method. Chemical investigation of the deep-purple colonial ascidian, Didemnum chartaceum collected from Swains Reefs led to the isolation of five new lamellarin alkaloids, which included the 20-sulfated derivatives of lamellarins B (94), C (95) and L (96), the 8-sulfated derivative of lamellarin G (97) and the non-sulfated compound, lamellarin Z (98). The known lamellarins A (63), B (80), C (64), E (65), G (67), and L (71) plus the triacetate derivatives of lamellarin D (82) and N (83) were also isolated. An aberration in the integration of signals in the 1H NMR spectra of the 20-sulfated derivatives (94-96) led to NMR relaxation studies. T1 values were calculated for all protons in the sulfated lamellarins (94-97) and their corresponding non-sulfated derivatives (80, 64, 71, 67). The protons ortho to the sulfate group in compounds (94-97) had T1 values up to five times larger than the corresponding protons in their non-sulfated derivatives (80, 64, 71, 67). A specimen of Eudistoma anaematum collected from Heron Island was shown to contain a new b-carboline alkaloid, eudistomin V (130), in addition to the two known metabolites, eudistomin H (105) and I (106). Part B. The known natural products, 1,3-diphenethylurea (29), 1,3-dimethylxanthine (30), 1,3-dimethylisoguanine (31) and the salts of tambjamine C (16), E (18) and F (19) were isolated from the ascidian, Sigillina signifera collected in Blue Lagoon, Lizard Island. Base hydrolysis on mixtures of the salts of tambjamine C (16), E (18) and F (19) resulted in the production of 4-methoxy-2,2-bipyrrole-5-carbaldehyde (26). This natural product template (26) was used in the generation of an enamine combinatorial chemistry library (98, 103-111) using solution-phase parallel synthesis. The biaryl compound, 4-(2-thienyl)-1H-pyrrole-2-carbaldehyde (59) was successfully synthesised using Suzuki-Miyaura coupling conditions and subsequently used as a template in the generation of an amine (67, 77, 80-87) and imine (78, 92-95) combinatorial library using solution-phase parallel synthesis.

This thesis describes the chemical investigations of several ascidian species collected from the Great Barrier Reef, Queensland, Australia. The thesis is divided into two separate components, Part A focuses on the isolation and structure elucidation of 11 previously undescribed ascidian metabolites. All structures were assigned using a combination of spectroscopic and/or chemical methods. Part B relates to the isolation and chemical conversion of a natural product to a combinatorial template. The natural product template was subsequently used in the generation of a solution-phase combinatorial chemistry library. A further two combinatorial libraries were generated from a synthesised model compound that was related to the natural product template. Part A. Investigation of Aplidium longithorax collected from the Swains Reefs resulted in the isolation of two new para-substituted cyclofarnesylated quinone derived compounds, longithorones J (30) and K (31). The former compound had its absolute stereochemistry determined by the advanced Mosher method. From an Aplidium longithorax collected from Heron Island, two new cyclofarnesylated hydroquinone compounds, longithorols C (46) and D (47) and a novel macrocyclic chromenol, longithorol E (48) were isolated. Longithorol C (46) had its absolute stereochemistry determined by the advanced Mosher method. Chemical investigation of the deep-purple colonial ascidian, Didemnum chartaceum collected from Swains Reefs led to the isolation of five new lamellarin alkaloids, which included the 20-sulfated derivatives of lamellarins B (94), C (95) and L (96), the 8-sulfated derivative of lamellarin G (97) and the non-sulfated compound, lamellarin Z (98). The known lamellarins A (63), B (80), C (64), E (65), G (67), and L (71) plus the triacetate derivatives of lamellarin D (82) and N (83) were also isolated. An aberration in the integration of signals in the 1H NMR spectra of the 20-sulfated derivatives (94-96) led to NMR relaxation studies. T1 values were calculated for all protons in the sulfated lamellarins (94-97) and their corresponding non-sulfated derivatives (80, 64, 71, 67). The protons ortho to the sulfate group in compounds (94-97) had T1 values up to five times larger than the corresponding protons in their non-sulfated derivatives (80, 64, 71, 67). A specimen of Eudistoma anaematum collected from Heron Island was shown to contain a new b-carboline alkaloid, eudistomin V (130), in addition to the two known metabolites, eudistomin H (105) and I (106). Part B. The known natural products, 1,3-diphenethylurea (29), 1,3-dimethylxanthine (30), 1,3-dimethylisoguanine (31) and the salts of tambjamine C (16), E (18) and F (19) were isolated from the ascidian, Sigillina signifera collected in Blue Lagoon, Lizard Island. Base hydrolysis on mixtures of the salts of tambjamine C (16), E (18) and F (19) resulted in the production of 4-methoxy-2,2-bipyrrole-5-carbaldehyde (26). This natural product template (26) was used in the generation of an enamine combinatorial chemistry library (98, 103-111) using solution-phase parallel synthesis. The biaryl compound, 4-(2-thienyl)-1H-pyrrole-2-carbaldehyde (59) was successfully synthesised using Suzuki-Miyaura coupling conditions and subsequently used as a template in the generation of an amine (67, 77, 80-87) and imine (78, 92-95) combinatorial library using solution-phase parallel synthesis.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Science
Full Text

This dissertation examines two issues related to the ecological and evolutionary consequences of sexual and asexual reproduction in colonial marine invertebrates. The first two chapters explore the extent to which the planktonic larval phase limits the distribution and abundance of a colonial ascidian, Oiplosoma similis. The third chapter examines some of the fitness consequences of alterations in the pattern of asexual reproduction by colony fragmention in similis. All research was carried out on the fringing coral reef surrounding Coconut Island which is located in Kaneohe Bay, Oahu, Hawaii.
Typescript. Thesis (Ph. D.)--University of Hawaii at Manoa, 1989. Includes bibliographical references.

The ascidian species Ciona savignyi and C. intestinalis are invasive species but show interspecific differences in their population response to hypo-saline stress associated with heavy winter-run off events that are predicted to become more frequent due to climate change. Despite an almost world-wide distribution, C. intestinalis seems to be more susceptible to hypo-saline stress than the geographically more limited C. savignyi. Given that the genomes of both species are fully sequenced, we were able to compare their proteomic response to both acute and chronic salinity to characterize the mechanisms that are responsible for setting tolerance limits to hyposaline conditions in these two congeneric species. For the acute hypo-saline stress experiment, we exposed each species to decreasing salinities, 100%, 85% and 70% full-strength seawater, for 6 hours followed by a 4-hour recovery at 100%. In the chronic salinity stress experiment, each species was kept at 100% or 85% with individuals removed for analysis during a 16-day time course. Organisms were dissected to remove the tunic, and 2D SDS-PAGE was performed to separate proteins and characterize changes in protein abundances. In the acute experiment, we determined 5% and 19% of the proteins to be significantly changing abundance in C. savignyi and C. intestinalis, respectively, due to the treatment effect. For both species in the chronic experiment, we determined over 40% of the proteins to be significantly changing abundance given the treatment, time, or interaction effect. Analysis of these proteins with MALDI TOF-TOF mass spectrometry has identified numerous proteins implicated in cellular stress responses, including energy metabolism (glycolysis, ATP & NADH production), cytoskeletal restructuring, and protein turnover, providing insights into the intense cellular restructuring that occurs following hypo-saline exposure.

Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2017.
In South Africa, squid fishing vessels need to find and then anchor above benthic squid egg beds to effect viable catches. However, waves acting on the vessel produce a dynamic response on the anchor line. These oscillatory motions produce impact forces of the chain striking the seabed. It is hypothesised that this causes damage to the squid egg bed beneath the vessels. Different mooring systems may cause more or less damage and this is what is investigated in this research. The effect of vessel mooring lines impact on the seabed during squid fishing is investigated using a specialised hydrodynamic tool commercial package ANSYS AQWA models. This study analysed the single-point versus the two-point mooring system’s impact on the seabed. The ANSYS AQWA models were developed for both mooring systems under the influence of the wave and current loads using the 14 and 22 m vessels anchored with various chain sizes. The effect of various wave conditions was investigated as well as the analysis of three mooring line configurations. The mooring chain contact pressure on the seabed is investigated beyond what is output from ANSYS AQWA using ABAQUS finite element analysis. The real-world velocity of the mooring chain underwater was obtained using video analysis. The ABAQUS model was built by varying chain sizes at different impact velocities. The impact pressure and force due to this velocity was related to mooring line impact velocity on the seabed in ANSYS AQWA. Results show the maximum impact pressure of 191 MPa when the 20 mm diameter chain impacts the seabed at the velocity of 8 m/s from video analysis. It was found that the mooring chain impact pressure on the seabed increased with an increase in the velocity of impact and chain size. The ANSYS AQWA impact pressure on the seabed was found to be 170.86 MPa at the impact velocity of 6.4 m/s. The two-point mooring system was found to double the seabed mooring chain contact length compared to the single-point mooring system. Both mooring systems showed that the 14 m vessel mooring line causes the least seabed footprint compared to the 22 m vessel.

The ascidian (subphylum Tunicata: class Ascidiacea) fauna along the southern African coast constitutes an important component of the sessile benthic reef fauna. Little is known of the species composition, biodiversity and distribution of ascidians on southern African intertidal and subtidal reefs. Past research on the ascidian fauna of South Africa was sporadic and limited, with only about one hundred and seventy species recorded during the last one hundred and twenty years. This is the first taxonomic study undertaken by a South African resident scientist. The study focused on six genera in four families (Euherdmaniidae, Polyclinidae, Pseudodistomidae and Didemnidae) belonging to the class Ascidiacea and suborder Aplousobranchia. Five species new to science, two Polyclinum, two Pseudodistoma and one Polysyncraton species are described. New additional information on the distribution of five species previously known to science, including one recorded for the first time along the South African coast, is presented. A literature review and comparison of the taxonomic important characteristics is made of all species known globally for the six genera. These six genera comprise twelve Euherdmania, fifteen Aplidiopsis, forty Polyclinum thirty-one Pseudodistoma, six Atriolum and sixty-eight Polysyncraton species.

The sea squirts Ciona intestinalis and C. savignyi have disparate distribution patterns, which may result from differences in their thermal tolerance limits. Because C. intestinalis, an almost cosmopolitan species, has a more widespread distribution, it is thought that it is better adapted to endure a wide range of temperatures. In order to compare the heat stress response between these two congeners, we studied global changes in protein expression, using a proteomics approach. To characterize the response to extreme heat stress, animals of both species were exposed to temperatures of 22°C, 25°C, and 28°C for 6 h, and then were left to recover at a control temperature (13°C) for 16 h. An additional experiment was conducted to assess the effect of mild-to-moderate heat stress including a 6 h exposure to temperatures of 18°C, 20°C, and 23°C, and a 16 h recovery at a control temperature (16°C). A quantitative analysis, using 2D gel electrophoresis and gel-image analysis, showed that in the high heat stress (HHS) experiment, 15% and 18% of the all protein spots detected demonstrated changes in expression in C. intestinalis and C. savignyi, respectively. In the low heat stress (LHS) experiment, 4% of the total number of proteins detected changed significantly in both C. intestinalis and C. savignyi. Using matrix-assisted laser desorption ionization (MALDI) tandem time-of-flight mass spectrometry, we were able to identify proteins with a 65-100% success rate, depending on species. Our results indicate that C. intestinalis maintains higher baseline levels of molecular chaperones and launches a quicker response to thermal stress than C. savignyi, suggesting it may be the more thermally tolerant of the two. In addition, actins, tubulins, and ATP-synthase F1 β-subunits were the most susceptible to proteolytic degradation, which may indicate that they have relatively higher thermal sensitivities.

Estuaries worldwide are under threat from urbanisation and development and will need effective management for their successful conservation. Coastal lakes and lagoons have been identified as one of the estuary types most susceptible to human impacts largely because of their isolated nature and slow flushing times. Management of estuaries will be most effective when based on a sound scientific understanding of the patterns of distribution, biology and ecology over the full range of biodiversity of these systems, however, such an understanding is lacking for many systems and many taxa. Studies of sponges and ascidians in coastal lakes and lagoons are rare compared to other taxa, particularly in the southern hemisphere. This study represents the first detailed scientific investigation of the ecology of sponges and ascidian in coastal lakes and lagoons of southeastern Australia. Consequently, a large part of this thesis was devoted to quantifying basic patterns of distribution. I started with a pilot study to develop an effective sampling design, followed by large-scale comparisons among different types of lake, comparisons among habitats within lakes and an environmental impact study. I concluded with a manipulative experiment to examine processes responsible for smallscale patterns of distribution of sponges in seagrass meadows.In the pilot study, distributions of sponges and ascidians were quantified at a hierarchy of three spatial scales in each of two coastal lakes. Nested analyses of variance were then used to identify spatial scales at which variation was significant. Most sponges and ascidians were very patchily distributed at a range of spatial scales from 10s of metres up to 100s of kilometres. Unlike other published examples of cost– benefit analyses, very few taxa were widespread over the larger spatial scales. Cost– benefit analyses done to determine the optimal sampling design revealed inclusion of patchily distributed taxa in analyses improved the overall precision of sampling for comparisons of assemblages among lakes.Large-scale comparisons of assemblages of sponges and ascidians were made among lakes of different size (big versus small), opening regime (mostly open to the ocean versus mostly closed) and level of environmental modification (extensively modified versus more pristine). Similar to other taxa studied in coastal lakes, in general there were more species in lakes mostly open to the ocean compared to the mostly closed lakes, and importantly, no sponges and only one species of ascidian was found in the small closed lakes. There also appeared to be an effect of the level of modification of a lake with relatively smaller abundances of ascidians in extensively modified lakes, and a complete absence of sponges from one of the extensively modified lakes.Habitat-associated patterns were examined at smaller spatial scales by comparing the distributions of sponges and ascidians with the species composition and percentage cover of seagrass and macroalgae within two lakes; St Georges Basin and Wallis Lake. Several patterns of association were observed, but these varied among species of sponge and ascidian. In St Georges Basin, the most common sponge, Aplysinella cf. rhax and the native ascidian Pyura stolonifera were positively correlated with the seagrass, Posidonia australis. In contrast, the introduced ascidian, Styela plicata was more abundant in areas dominated by the seagrass, Zostera capricorni. In Wallis Lake, sponges were most diverse and some species most abundant in large beds of the macroalga, Lamprothamnion sp., while other sponges were found only on the holdfasts of brown macroalgae. In both lakes, sponges were generally less common in areas dominated by dense meadows of the seagrass, Zostera capricorni.Among the many anthropogenic impacts threatening the ecology of coastal lakes, the discharge of cooling water from coal-fired power stations represents an almost ideal case study from which to develop appropriate sampling regimes for detecting impacts on sponges and ascidians. Using reference locations both within and outside Lake Macquarie which has two cooling water outlets, I found assemblages of sponges and ascidians were often more diverse, more abundant and less temporally variable near to the outlets compared to reference locations.Based on the observation that the sponge, Suberites sp. which contains photosynthetic symbionts was absent from meadows of dense Zostera capricorni, I used in situ manipulative experiments in Smiths Lake to investigate processes which maybe affecting their distribution. Individual Suberites sp. were shaded, had water flow reduced and were transplanted into areas of dense Z. capricorni. There were no measurable short-term effects of shading or reduced water flow, but transplanted sponges were quickly eaten and I concluded predation by fish was likely to be a key process determining small-scale patterns of distribution of Suberites sp. in seagrass meadows. This result was in stark contrast to the majority of previous studies of the effects of seagrass habitat complexity on predation which have found predation to decrease with increasing density or complexity.In conclusion, I have sought to provide sound scientific information to aid in the management of these systems. A simple, but nevertheless key finding was that sponges and ascidians are indeed present and widespread in coastal lakes and lagoons of southeastern Australia and should not be continually overlooked in the management and conservation of these systems. Conservation will be complex and requires an understanding of environmental impacts and the consequences of management on the full range of biodiversity. The distributions of sponges and ascidians at large ‘lakewide’ scales appear to behave similarly to other taxa. Management strategies which change the characteristics of a lake at these large spatial scales such as artificial openings of entrances could therefore be predicted to have similar effects across a range of taxa including sponges and ascidians. In contrast, at smaller spatial scales such as the complexity of seagrass meadows, some species of sponges and ascidians may behave very differently from other taxa. At present, our understanding of these naturally variable and complex systems is incomplete and will require ongoing scientific investigation to identify natural patterns of distribution, environmental impacts, important natural processes and the ecological consequences of management strategies.

A presente dissertação analisa diversas intervenções arquitetónicas para responder ao aumento do nível do mar. Este conceito desenvolve um problema costeiro1 portador de perdas culturais e naturais, pois vários aglomerados urbanos desenvolveram-se junto ao mar, tal como um vasto Património Mundial da UNESCO2. Contudo, a construção tem contribuído indiretamente para esse problema, porque ela é responsável por metade das emissões mundiais de carbono, onde apenas o cimento contribui oito porcento do carbono global, e o aço nove porcento3. O estudo dissertativo analisa também diversas ideologias que certos arquitetos adotaram para desenvolverem uma melhoria ambiental que proporciona uma qualidade de vida melhor, acessível à população, simultaneamente respeitando e enaltecendo o território. A cidade de Lisboa nasceu num cume, contudo foi-se direcionando para o rio, ultrapassando até a linha costeira. Atualmente, partes do rio encontram-se inalcançáveis, obstruídas pela construção. A intervenção dissertativa pretende “naturartificializar” parte da frente em função do aumento freático; ABSTRACT: The present dissertation analyzes several architectural interventions to respond to sea level rise. This concept develops a coastal problem1 with cultural and natural losses, as several urban areas have developed by the sea, such as a vast UNESCO World Heritage Site2. However, construction has indirectly contributed to this problem because it accounts for half of the world’s carbon emissions, where cement alone contributes eight percent of global carbon, and steel nine percent3. The study also analyzes several ideologies that certain architects adopted to develop an environmental improvement that provides a better quality of life, accessible to the population, while respecting and extolling the territory. The city of Lisbon was born on a ridge, but it went towards the river, extending to the coast line. At the present, parts of the river are unreachable, obstructed by construction. The dissertation intervention intends to “naturartificialize” the front due to the water table increase.

A recent method in aero engine production is to fabricate components from smaller pieces, rather than machining them from large castings. This has made laser beam welding popular, offering high precision with low heat input and distortion, but also high productivity. At the same time, the demand for automation of production has increased, to ensure high quality and consistent results. In turn, the need for sensors to monitor and control the laser welding process is increasing. In laser beam welding without filler material, the gap between the parts to be joined must be narrow. Optical sensors are often used to measure the gap, but with precise machining, it may become so narrow that it is difficult to detect, with the risk of welding in the wrong position. This kind of problems can cause severe welding defects, where the parts are only partially joined without any visible indication. This thesis proposes the use of an inductive sensor with coils on either side of the gap. Inducing currents into the metal, such a sensor can detect even gaps that are not visible. The new feature of the proposal is based on using the complex response of each coil separately to measure the distance and height on both sides of the gap, rather than an imbalance from the absolute voltage of each coil related to gap position. This extra information allows measurement of gap width and misalignment as well as position, and decreases the influence from gap misalignment to the position measurement. The sensor needs to be calibrated with a certain gap width and height alignment. In real use,these will vary, causing the sensor to be less accurate. Using initial estimates ofthe gap parameters from the basic sensor, a model of the response can be used to estimate the measurement error of each coil, which in turn can be used for compensation to improve the measurement of the gap properties.The properties of the new method have been examined experimentally, using a precise traverse mechanism to record single coil responses in a working range around a variable dimension gap, and then using these responses to simulate a two coil probe. In most cases errors in the measurement of weld gap position and dimensions are within 0.1 mm.The probe is designed to be mounted close to the parts to be welded, and will work in a range of about 1 mm to each side and height above the plates. This is an improvement over previous inductive sensors, that needed to be guided to the mid of the gap by a servo mechanism.

This thesis investigates the chemistry of 25 ascidian species collected from Algoa Bay, South Africa with a concerted focus on metal accumulation by these ascidians and the possible interaction of these metals with ascidian metabolites. Chapter 2 details the screening techniques employed to establish the presence of nitrogenous metabolites (1H- 15N HMBC), hyper-accumulated metal ions (ICP-MS) and potential metal ion/ ascidian metabolite complexes (LC-ICP-MS/ESI-MS). Unfortunately, exhaustive attempts to detect intact metal ion/ascidian metabolite complexes through the use of liquid chromatography with parallel inductively coupled plasma mass spectrometry/electrospray mass spectrometry (LC-ICPMS/ ESI-MS) were unsuccessful. However, the LC-ICP-MS/ESI-MS data obtained for the crude organic extracts of six of the Algoa Bay ascidian species, Distaplia skoogi, Aplidium monile, Aplidium sp., Didemnum sp., Leptoclindines sp. and Polycitor sp. enabled identification of a number of ten halogenated metabolites, namely the indoles 2.28-2.30, and the tyramine and tyrosine derivatives (2.31-2.33, 2.41, 2.43, 2.44 and 2.46), within the ascidian extracts. This study confirmed that LC-ICP-MS/ESI-MS is a powerful tool for the dereplication of halogenated metabolites in complex mixtures especially where these compounds are present in very small amounts. This study is also the first report of these compounds (eight of which are known) in African ascidians. Compounds 2.32 and 2.46 have not been reported before from a marine source. Compounds 2.28-2.30 and 2.33 were present in sufficient amounts in the respective ascidian extracts to allow their isolation and structure elucidation using standard spectroscopic techniques Chapter 3 explores the ability of ascidians to accumulate a wide range of metal ions at concentrations which are often orders of magnitude higher than those of the surrounding sea water. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the total ion concentrations of 24 metals in 25 Algoa Bay ascidian species. To the best of our knowledge this is the largest and most extensive investigation of metal concentrations in a group of different ascidians occurring in the same area. Hypotheisizing that the metal ion concentrations for each ascidian specimen screened may represent a unique fingerprint for each specimen principal component analysis (PCA) was used in an attempt to establish whether there were spatial, temporal or phylogenetic relationships associated with the metal concentration fingerprints of the ascidians that formed part of this study. The PCA results showed that there were no statistically significant relationships between ascidian metal ion concentrations and either the collection year or the collection site of the ascidians. However, species from the family Didemnidae provided the clearest statistical evidence supporting a phylogenetic relationship between these ascidians and their hyperaccumulated metal ion profiles. Furthermore, these results suggested that ascidian species are indeed actively concentrating metal ions from the surrounding sea water and are not simply sinks for passively accumulated metal ions. Interestingly, the concentration of vanadium in the set of ascidians studied did not appear to correlate with any of the other metals accumulated by these ascidians suggesting that there is possibly a unique method employed for the accumulation of vanadium by ascidians. Chapter 4 investigated this possibility further after the nucleosides 4.10, 4.11, 4.13, 4.15, 4.17 and 4.40 were isolated from the vanadium accumulating ascidian Aplidium monile. Studies into the interactions between nucleosides and vanadyl are unfortunately rare and usually qualitative in nature with limited information provided about the stability or structures of the complexes formed. The vanadyl accumulating aplousobranch ascidians e.g. Aplidium monile dominated our study of Algoa Bay ascidians therefore providing us with the rationale to investigate the relatively little studied binding ability and stability of vandyl-nucleoside complexes. Potentiometric studies were conducted to determine the stability constants of complexes formed between the oxovanadium ion vanadyl (VO2+) and the commercially available nucleosides 4.10-4.14. The data afforded by this analysis clearly confirmed the complexity of the vanadyl/nucleoside complexation and suggested that guanosine (4.12) formed the most stable complex with oxovanadium ions. We were also able to establish a third protonation constant for the hydroxyl moiety in 4.12 with a logK 8.87 which has not been previously reported. Finally, Chapter 5 revisited the cytoxicity two Algoa Bay ascidians, Clavelina sp. and Atriolum marinense the extracts from which produced promising bioactivity results in previous studies against oesophageal cancer cells. The HP-20 fractionated extracts of Clavelina sp. and Atriolum marinense proved to be similalrly cytotoxic to breast cancer cells. With the exception for the 100% acetone(aq)fractions the NMR data for both species suggested that most active non polar fractions were dominated by what appeared to be structurally unremarkable fatty acid glycerides and as such were not pursued further. Purification of the 100% acetone(aq)fraction of A. marinense resulted in the isolation of a styrene trimer, 5.1, common to both ascidian extracts. The NMR simulation software WIN-DAISY was employed to confirm the structure of 5.1. Attempts to establish if 5.1 was an isolation artefact or a product of marine pollution were inconclusive

Background New Zealand (NZ) sea lions (Phocarctos hookeri) are one of the rarest otariids (i.e. eared seals) in the world. They are listed as "Nationally Critical" under NZ conservation policy and are recognized as "Vulnerable" in the International Union for the Conservation of Nature's (IUCN) Red List of Threatened Species. Currently, the Auckland Islands population of NZ sea lions is in decline and facing persistent threats from commercial trawl fisheries. This population is at-risk of fisheries interactions which may result in bycatch and/or resource competition, particularly with the Southern Arrow squid (Nototodarus sloani) trawl fishery (referred to as 'SQU6T' in New Zealand fisheries management policy). Bycatch of NZ sea lions in the Southern Arrow squid trawl fishery has been historically biased towards females, and resource limitation from competition with this fishery may also be influencing female fecundity. This female-bias in fishery interactions appears to be a result of sex differences in habitat use among adult NZ sea lions. Recent research suggests that sex differences in habitat use may also extend to juvenile age classes. Juvenile sea lions are particularly susceptible to fisheries-induced resource competition because of: (a) age- and size-specific constraints affecting juvenile foraging success; and possibly (b) greater risk of capture in trawling gear due to weaker swimming and diving capabilities, and inexperience. Understanding juvenile NZ sea lion habitat use in relation to the SQU6T trawl fishery is therefore essential to assessing and managing fisheries interactions. Thesis aims The aims of this Thesis are to: (1) identify discrete behaviours from juvenile NZ sea lion dive data through the development and application of a statistical modelling approach, known as a state-space model (SSM); (2) describe the spatio-temporal features of the vertical distribution of those behaviours, and examine how they are influenced by biological factors; and (3) characterise the horizontal distribution of those behavioural classes, in conjunction with fishing effort, to determine potential demographic biases to the interactions between juvenile NZ sea lions and the Southern Arrow squid trawl fishery. Methodology In a prior study, dive and spatial data were collected by time-depth recording (TDR) and platform-transmitting terminal (PTT) tags fitted to juvenile NZ sea lions from Enderby Island, in the Auckland Islands. The data presented in this Thesis form a subset of those data and comprise TDR and PTT tag data of durations between 8 and 17 days from five juvenile sea lions (three females and two males). The TDR data were used in an innovative particle-filtering SSM, developed by Dowd and Joy (2011), which enables the determination of fine-scale behaviours from high-resolution vertical velocity data. This statistically sophisticated algorithm models stochastic animal movement from short segments of dive data and then predicts latent movement parameters for each segment. These movement parameters are then interpreted for their periodicity to infer the foraging and non-foraging behaviours associated with individuals' dives. Findings Chapter 2 describes the statistical underpinnings of the SSM and how this modelling approach was adapted for use with juvenile NZ sea lion TDR data. This Chapter explored two parameters associated with fitting the model to dive data: time-window length and the model used for variance estimation procedures. The results of this exploration suggested that time-window length is of significant importance to estimating the output parameters used for the behavioural classification of dive data. Furthermore, the results indicated that a larger time window than those tested in this Chapter should be employed in future studies attempting to adapt this particular SSM to juvenile NZ sea lion dive data. Chapter 3 focuses on the influence of several biological characteristics on vertical habitat use in juvenile NZ sea lions, and how these differ when individuals were foraging versus surface swimming. The results of this study can directly inform on the diving behaviours which might predispose particular demographics within the juvenile age-class to direct and indirect fisheries interactions with the SQU6T Arrow squid trawl fishery. Linear Mixed Effects (LME) models were used to examine the influence of age, sex, and mass on mean and maximum dive depth and dive duration, and the results were compared between behavioural classes estimated by the particle-filtering SSM adapted in Chapter 2. The results of the LME models suggest that sex, age, mass, and the interaction between age and mass, all play important roles in juvenile NZ sea lion diving behaviour, influencing both the depths and durations of their dives. Males and larger individuals utilised deeper vertical habitat in general, and for longer durations, than did females or smaller animals. However, females spent greater amounts of time near their depth maxima. Both sexes had deeper and longer dives when foraging opportunistically than when foraging continuously (i.e. pseudo-periodically). Surprisingly, the models also suggested a negative relationship between dive depth and duration and age. This indicates that the high inter-individual variation in diving behaviours, coupled with the small sample size may have distorted the ability of the LME models to generate accurate predictions using age as a model parameter. Collectively, the results of this study indicate that females and larger animals diving to their maximum depths spend the greatest amount of their time within the depth ranges of schooling Arrow squid, potentially putting them at greater risk of interaction with the Arrow squid trawl fishery. Chapter 4 investigates the spatio-temporal overlap between juvenile foraging habitat and the distribution of fishing effort by the SQU6T trawl fishery, and sex differences in habitat use. Spatial data collected by PPT tags were linearly interpolated to the behavioural classifications from the SSM (Chapter 3). This enabled spatial characterisation of juvenile foraging habitat and foraging intensity (a function of time spent foraging within an area). These data were then overlaid to distributions of fishing intensity to examine the potential for sex-biased interactions between juvenile NZ sea lions and the SQU6T trawl fishery. Visual analyses of the spatial distributions of individuals' foraging-specific habitat use suggested that foraging habitat varies between sexes. However, statistical analyses indicated that sexual segregation of foraging habitat was insignificant for the five individuals. Furthermore, the proportion of foraging events and effort within high-use trawling areas of the Arrow squid fishery were exceedingly similar for both sexes, illustrating that juvenile male foraging habitat extends into fishing zones. The results of these preliminary analyses indicate a greater potential for bycatch and resource competition between juvenile males and the Southern Arrow squid trawl fishery than previously suggested. The small sample size and high inter-individual variation in the dive and spatial data made it difficult to validate patterns in the results of analyses on sex differences in juvenile NZ sea lions. Nevertheless, preliminary results from this Thesis support the application of a particle-filtering SSM to behavioural assessments of juvenile NZ sea lions, and their interactions with the Southern Arrow squid trawl fishery. Consequently, this Thesis provides valuable information to support future research pursuing these methods and questions.

The Square Kilometre Array (SKA) is a multibillion and a multinational science project to build the world’s largest and most sensitive radio telescope. For a very large field of view, the combined collecting area would be one square kilometre (or 1, 000, 000 square metre) and spread over more than 3,000 km wide which will require a massive count of antennas (thousands). Each of the antennas contains hundreds of low noise amplifier (LNA) circuits. The antenna arrays are divided into low, medium and high operational frequencies and located at different positions to boost up the telescope’s scanning sensitivity.The objective of this work was to develop and fabricate fully on-chip LNA circuits to meet the stringent requirements for the mid-frequency array from 0.4 GHz to 1.4 GHz of the SKA radio astronomy telescope using Monolithic Microwave Integrated Circuit technology (MMIC). Due to the number of LNA reaching figures of millions, the fabricated circuits were designed with the consideration for low cost fabrication and high reliability in the receiver chain. Therefore, a relaxed optical lithography with Lg = 1 µm was adopted for a high yield fabrication process.Towards the fulfilment of the device’s low noise characteristics, a large number of device designs, fabrication and characterisation of InGaAs/InAlAs/InP pHEMTs were undertaken. These include optimisations at each critical fabrication steps. The device’s high breakdown and very low gate leakage characteristics were further improved by a combination of judicious epitaxial growth and manipulation of materials’ energy gaps. An attempt to increase the device breakdown voltage was also employed by incorporating Field Plate structure at the gate terminal. This yielded the devices with improvements in the breakdown voltage up to 15 V and very low gate leakage of 1 µA/mm, in addition to high transconductance (gm) characteristic. Fully integrated double stage LNA had measured NF varying from 1.2 dB to 1.6 dB from 0.4 GHz to 1.4 GHz, compared with a slightly lower NF obtained from simulation (0.8 dB to 1.1 dB) across the same frequency band.These are amongst the attractive device properties for the implementation of a fully on-chip MMIC LNA circuits demonstrated in this work. The lower circuit’s low noise characteristic has been demonstrated using large gate width geometry pHEMTs, where the system’s noise resistance (Rn) has successfully reduced to a few ohms. The work reported here should facilitate the successful implementation of rugged low noise amplifiers as required by SKA receivers.

Students‟ motivational beliefs and self-regulatory practices have been identified as instrumental in influencing the engagement of students in the learning process. An important aim of science education is to empower students by nurturing the belief that they can succeed in science learning and to cultivate the adaptive learning strategies required to help to bring about that success. The lack of research on the influence of the learning environment on students‟ motivation and self-regulation provided the impetus for this research. The primary aim of this study was to investigate and identify salient psychosocial features of the classroom environment that influence students‟ motivation and self-regulation in science learning.The first imperative was the development and validation of an instrument to measure salient factors related to the motivation and self-regulation of students in lower secondary science classrooms. The development of the instrument involved identifying key determinants of students‟ motivation and self-regulation based on sound theoretical and research underpinnings. Once the instrument was developed, a pilot study involving 52 students from two grade 8 science classes was undertaken in addition to in-depth qualitative information gathered from 10 experienced science teachers and 12 grade 8 students. Quantitative data were collected from 1,360 students across grades 8, 9 and 10 in five public schools in Perth, Western Australia. Analyses of the data suggest that the survey has strong content, face, convergent, discriminant, concurrent and predictive validity when used with lower secondary students. Quantitative data, gathered from the same sample, established the convergent, discriminant, concurrent and predictive validity of the What Is Happening In this Class? (WIHIC) learning enviromnment instrument when used in lower secondary science classes.Partial Least Square (PLS) based Structural Equation Modeling (SEM) analysis of the data found that students‟ perceptions of investigation, task orientation and student cohesiveness were key determinants of students‟ motivation and self-regulation in science learning. The extent to which students‟ perceive the teacher to be supportive was strongly associated with their learning goal orientation and task value, whilst student involvement was a strong predictor of self-efficacy in science learning. The findings indicated that all three motivational constructs (learning goal orientation, task value and self-efficacy) were strong predictors of students‟ self-regulation in science learning. The most influential motivational belief on boys‟ and girls‟ self-regulation is self-efficacy followed by learning goal orientation. Although for boys the influence of task value was significant, for girls this construct appeared to have a limited impact on their self-regulation in science learning.The present study made distinctive contributions to the field of learning environment as well as to science education as it was the first study in within the field of learning environment research to examine the influence of psychosocial learning environment on both student motivation and self-regulation in the area of science learning. The methodological contribution is the use of a comprehensive and rigorous construct validity framework to develop and validate an instrument to measure students‟ motivation and self-regulation in science learning. The use of the PLS based SEM data analyses in the examination of the research model provided renewed rigor and depth to the interpretation of results. The practical implications presented possible opportunities for educators to plan, and to put into practice, effective pedagogical strategies aimed at increasing students‟ motivation and self-regulation in science learning. The results from the moderating role of gender could be utilised to design targeted intervention programmes that may differ in terms of orientation for girls and boys. The newly-developed survey could be practically valuable as an expedient tool for gathering information that may guide classroom teachers in refocusing their teaching practices and help to evaluate the effectiveness of intervention programmes. Although the focus of this research is on science learning, the findings probably could help educators to understand and improve student motivation and self-regulation in other subject areas.

Invasive species constitute a major threat to global biodiversity and cause important economic losses and ecological impacts. In the marine realm, ascidians include several aggressive invasive species, some of which have worldwide colonisation ranges, such as Didemnum vexillum. In this thesis, some biological and ecological characteristics implicated in the invasiveness of the species are assessed. First, we performed a 20 month monitoring to determine settlement and growth preferences of invasive ascidian species in the Ebro Delta aquaculture facility, including D. vexillum. Our results indicated that D. vexillum has a preference for complex substrates. To minimise fouling on bivalves, spat immersion during fall and below 1 m depth is recommended. To detect new introduced species, a follow-up program based on occurrences would be sufficient. Second, a protocol for small DNA samples combining whole genome amplification (WGA) and genotyping-by-sequencing (GBS) was developed and applied to D. vexillum using a single zooid per colony to determine patterns of genomic diversity and differentiation, describe the colonisation history of the species, and study its capability to form chimeras. Our results confirmed that Japan is in the native area of the species and only one clade spread worldwide. We found that the two main mitochondrial clades are strongly differentiated at the genomic level suggesting reproductive isolation, we determined that three independent colonisation events shaped the global distribution of the species, and we found that populations are diverse and well differentiated indicating a high expansion potential of D. vexillum. Third we detected high prevalence of chimerism, and fusion was unlinked to global genetic relatedness. Finally, we analysed the microbiome of D. vexillum that showed markedly different composition than a congeneric species and water. The invasive clade had a small but abundant core and a highly diverse variable microbiome component with a strong capacity to enrich the symbionts from the environment. The microbiome structure correlated to host genetic distance, temperature and geographical distances, pointing to vertical and horizontal transmission. In conclusion, D. vexillum is an aggressive invasive species with a high adaptive capacity that may contribute to the invasiveness of this global pest.

The largest 21st century radio telescope, the Square Kilometre Array (SKA) is now being planned, and the first phase of construction is estimated to commence in the year 2016. Phased array technology, the key feature of the SKA, requires the use of a tremendous number of receivers, estimated at approximately 37 million. Therefore, in the context of this project, the Low Noise Amplifier (LNA) located at the front end of the receiver chain remains the critical block. The demanding specifications in terms of bandwidth, low power consumption, low cost and low noise characteristics make the LNA topologies and their design methodologies one of the most challenging tasks for the realisation of the SKA. The LNA design is a compromise between the topology selection, wideband matching for a low noise figure, low power consumption and linearity. Considering these critical issues, this thesis describes the procedure for designing a monolithic microwave integrated circuit (MMIC) LNA for operation in the mid frequency band (400 MHz to 1.4 GHz) of the SKA. The main focus of this work is to investigate the potential of MMIC LNA designs based on a novel InGaAs/InAlAs/InP pHEMT developed for 1 µm gate length transistors, fabricated at The University of Manchester. An accurate technique for the extraction of empirical linear and nonlinear models for the fabricated active devices has been developed. In addition to the linear and nonlinear model of the transistors, precise models for passive devices have also been obtained and incorporated in the design of the amplifiers. The models show excellent agreement between measured and modelled DC and RF data. These models have been used in designing single, double and differential stage MMIC LNAs. The LNAs were designed for a 50 Ω input and output impedance. The excellent fits between the measured and modelled S-parameters for single and double stage single-ended LNAs reflects the accurate models that have been developed. The single stage LNA achieved a gain ranging from 9 to 13 dB over the band of operation. The gain was increased between 27 dB and 36 dB for the double stage and differential LNA designs. The measured noise figures obtained were higher by ~0.3 to ~0.8 dB when compared to the simulated figures. This is due to several factors which are discussed in this thesis. The single stage design consumes only a third of the power (47 mW) of that required for the double stage design, when driven from a 3 V supply. All designs were unconditionally stable. The chip sizes of the fabricated MMIC LNAs were 1.5 x 1.5 mm2 and 1.6 x 2.5 mm2 for the single and double stage designs respectively. Significantly, a series of differential input to single-ended output LNAs became of interest for use in the Square Kilometre Array (SKA), as it utilises differential output antennas in some of its configurations. The single-ended output is preferable for interfacing to the subsequent stages in the analogue chain. A noise figure of less than 0.9 dB with a power consumption of 180 mW is expected for these designs.

The New Zealand (NZ) sea lion Phocarctos hookeri is the only pinniped endemic to NZ with a population of approximately 12,000 individuals. Its breeding range is currently restricted to NZ sub-Antarctic islands, and it has failed to recolonise its pristine distribution around the NZ main islands despite its protection since 1881. The current hypothesis is that the population growth of this pinniped is limited by the distribution of suitable prey on the Auckland Islands (50°30'S, 166°E) shelf, and by the direct and indirect pressure exerted by the arrow squid Nototodarus sloani fishery. However, this hypothesis has not been fully tested to date as there has been limited information on the diet of the NZ sea lion and their potential prey. The objective of this thesis is to analyse the diet of NZ sea lions over several years with particular emphasis on the most reproductively important segment of the population: lactating females. This thesis provides the first quantification by percentage mass of the diet of NZ sea lion using a combination of stomach content analysis, qualitative fatty acid (FA) analysis, and quantitative FA signature analysis (QFASA). Stomach contents and blubber FAs were analysed from 121 individuals incidentally caught (by-caught) in the southern arrow squid fishery from the years 1997 to 2006. The blubber FAs of 78 freeranging lactating females captured at Enderby Island, Auckland Islands, were also examined during January and February of 2000 to 2005. Data obtained from both stomach analysis and QFASA indicate that arrow squid, rattails Macrouridae, hoki Macruronus novaezelandiae and red cod Pseudophycis bachus are key prey species for NZ sea lions in the Auckland Islands region. Because these prey species live mostly at depths greater than 200 m, lactating females must undertake long foraging trips and dive regularly to greater depths than other sea lion species. Data from QFASA indicates that this foraging pattern is conducted over an extended period through the summer and autumn. The daily food requirement of a lactating female was estimated by a simple energetic model to be greater than 20% of its body mass. During years of low arrow squid recruitment such as 1999 and 2001, the amounts of squid required by the NZ sea lion population may have been similar to the amount harvested by the fishery, suggesting that resource competition is likely to occur between the arrow squid fishery and NZ sea lions in years of low squid abundance. Half of the fishing activity of the southern squid fishery occurs in the north of the Auckland Islands shelf where NZ sea lions forage, leading to incidental captures every year. This research emphasises that management of the NZ sea lion must not only consider the direct interactions with the arrow squid fishery, but also the likelihood of food resource competition between the fishery and NZ sea lions.

Este trabalho tem como objetivo estudar a influência da geometria de suspensão do veículo nas atitudes da massa suspensa. Apresenta um confronto entre obras e autores e está segmentada em três partes; onde na primeira parte são definidos os conceitos básicos como dive, squat, lift, anti-dive, anti-squat, anti-lift e equivalente trailing-arm; na segunda parte são apresentadas as limitações e os novos conceitos definidos por R. S. Sharp e na terceira parte é apresentado o modelo dinâmico bidimensional introduzido por Fu-Cheng Wang. Apresenta um modelo virtual em sistema de multi-corpos desenvolvido no programa ADAMS, com todos os subsistemas que compõe um veículo completo. Inova ao trazer como objeto de estudo um veículo de competição (fórmula SAE) que possui como particularidade o sistema de suspensão push-rod. Surpreende com os resultados obtidos, pois, contrariam os conceitos básicos encontrados na maioria dos livros
This work has objective study the influence of suspension geometry on the sprung mass attitudes. It presents a confrontation among works and authors and this segmented in three parts; where in the first part the basic concepts are defined, dive, squat, lift, anti-dive, anti-squat, anti-lift and equivalent trailing-arm; in the second part the limitations are presented and the new concepts are defined for R. S. Sharp and in the third part are presented the bidimensional dynamic model introduced by Fu-Cheng Wang. It presents a virtual model in system of multi-bodies developed in the program ADAMS, with all the subsystems that composes a complete vehicle. It innovates when bringing such object to study one vehicle of competition (formula SAE) that it has a particularity suspension system push-rod. It surprises with results because it’s opposite of the basic concepts which is present in the majority of books

The ethical decision making (EDM) process of individuals has proven to be very challenging due to the multitude of complex and varied factors that contribute to this behaviour. Nevertheless, many theoretical frameworks have been proposed to describe such behaviour. Despite the increasing number of EDM models and practices, reports of unethical incidents and illegal behaviour, especially in organizations, continue to appear. This problem is in part related to the failure of EDM models that do not adequately explain the antecedent factors of ethical behaviour by individuals in organizations. As a result, there is a gap between theory and practice. Hence, the main objective of this study is to address these shortcomings by exploring and empirically examining the antecedents in the EDM process and by developing a behavioural model that encompasses a fully functional model of individual ethical behaviour.Furthermore, most of the major frameworks have been formulated from a Western perspective. The current research was conducted in the Malaysian context, using a model that accounts for cultural differences. The most generally accepted concept is that culture is a key determinant of an individual's ethical ideology, which affects an individual’s inclination to behave ethically. In other words, culture acts as a guideline in determining whether certain practices are appropriate and acceptable. However, individuals in organizations also have an obligation to comply the culture in their work setting. Therefore, the culture of ethical practices in an organization is expected to play an important role in the process of EDM. In addition, literature has established the moderating effect of gender, age and level of education in such behaviour. Therefore, the current research also further investigated the relationship among the components of the EDM process, which has thus far not been given proper attention.A two-phase sequential mixed-method approach, consisting of qualitative and quantitative approaches, was carried out in this research. In the qualitative part, a field study of semi-structured interviews was conducted with the objective of testing the applicability of the initial model besides exploring the dimensionality of the construct. The data was analyzed using content analysis through Nvivo software. Based on the analysis, the dimensionality of the constructs was identified and two more relevant antecedent factors were detected, namely parental values and religiosity. Thus, these two factors were added to the comprehensive research model. A survey was conducted among managers from Malaysia large organizations to collect quantitative data. The data was analyzed using a Partial Least Square (PLS) based Structural Equations Modelling (SEM) tool. In addition, multi-group analysis of PLS was also employed.The major findings of this research have confirmed the influence of ethical ideology as the major determinant of the EDM process. Furthermore, results have demonstrated the role of culture as the antecedent of an individual’s ethical ideology. Interestingly, the influence of parental values and religiosity, which was derived from the field study, was also confirmed. Findings also verified the moderating effect of the organizational ethical culture in enhancing a moral awareness of an individual’s EDM process. With regards to the relationship among the components of the EDM process, findings revealed sequential and interrelationship links between the components. On the other hand, the moderating effect of gender, age and level of education in the EDM process was not detected. Overall results confirm the multidimensional construct and the complexity of such a process. This research provides a significant contribution to the existing knowledge in the EDM area. Most importantly, an understanding of the antecedents and the processes of EDM provides guidelines for organizations in developing better ethical programs and policies in order to promote and encourage ethical behaviour. Perhaps a major contribution of this research is the implication for managers to enhance the process of EDM in organizations.

Marine non-native species threaten economic and environmental health, making it crucial to understand factors that make them successful. Research on these species, therefore, allows for greater preparedness and informed management of biological invasions and increases understanding of elements structuring biological communities. Among the marine non-native species, and particularly the fouling community, non-native ascidians are a taxon of particular concern because they can crowd out native benthic species and smother mariculture products. This thesis addresses management for ascidians and other fouling organisms and includes research on the invasiveness of this taxon in addition to the invasibility of recipient fouling communities. On the West Coast of the U.S., limited efforts have been made to coordinate biofouling management across states, despite the myriad vectors increasing propagule pressure over time along coastal states. Building on recent state and local efforts, I developed a Pacific Regional Biofouling Plan for the states of Oregon and Washington to help start a consensus-driven process by which these states could create a forum for more comprehensive coordination efforts, following California's lead. As states address authority gaps, the biofouling management framework I've written is meant to be used to guide the conversation between managers as various stages of coastal management are realized. To better inform the scope and efficacy of management and regulatory efforts, the study of invasions ecology asks and aims to answer questions regarding recipient community interactions and characteristics of the non-native species themselves. Studies that identify characteristics that make ascidians successful (invasiveness) and determine the influence native communities have on their success (invasibility) are important for assessing overall risk of establishment and spread from non-native ascidians. Therefore, I aimed to: 1) explore the hypothesis that fouling communities on suspended, artificial structures are more invasible than benthic habitats; and 2) identify characteristics influencing predation patterns on the native Distaplia occidentalis versus non-native ascidian species using mensurative and experimental studies in Charleston Marina, Oregon. I conducted a series of feeding assays, surveys, and a caloric content analysis. Feeding assays were conducted with a suite of predators. The flatworm predator (Eurylepta leoparda) was found to be highly selective on the native ascidian Distaplia occidentalis, and only preyed on whole colony samples. Feeding assay data suggest that test (tunic) structure or thickness may be an influential factor affecting nudibranch (Hermissenda crassicornis) predation rates on native versus non-native ascidians, with greater predation on the native ascidian species. Non-native ascidians may escape predation in floating but not benthic environments on the Oregon coast due to their palatability characteristics, likely tunic structure and low caloric content. In this case, this suite of predators may indirectly facilitate the invasion of docks but provide at least partial resistance to the invasion of natural benthic areas. The chapters herein address gaps in management and scientific knowledge regarding non-native species of the marine fouling community. Future work enhanced by my efforts could include the development of the coastal biofouling management plan, coordinated by the Western Regional Panel on Aquatic Invasive Species Coastal Committee, and broadening the geographic and taxonomic scope of my research with a more comprehensive study of predator-prey interactions involving non-native ascidians and a diverse suite of predators. These interactions may be an important factor in explaining the success of ascidians and other fouling organisms on floating structures and lack of success on nearby benthic substrata.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
From the theory on structure of capital and the application of structural equations a model was considered to evaluate the indebtedness of the public companies in Brazil. The effect of direct and indirect costs of bankruptcy, tax benefits, agency costs of free cash flow and the agency costs of borrowing. Computed the results, which was opted to analyzing an alternative model that indicates the relevance of the capital demand and offers effects in the level of companies indebtedness. One met evidences on the relevance of direct and indirect costs of bankruptcy and agency costs of borrowing in the determination of the capital structure in analyzed companies.
A partir da teoria sobre estrutura de capital e da aplicação de equações estruturais foi proposto um modelo para avaliar o endividamento das companhias abertas no Brasil. Foram considerados os efeitos das dificuldades financeiras, benefícios fiscais, agency de capital próprio e de capital de terceiros. Computado os resultados optou-se por analisar um modelo alternativo segundo o qual encontramos indícios e relevância dos efeitos da demanda e oferta de capital no nível de endividamento das empresas. Encontrou-se evidências que dificuldades financeiras e agency de capital de terceiros influem na determinação da estrutura de capital das empresas analisadas.

Nous proposons dans cette thèse de caractériser quantitativement la variabilité à différentes échelles au cours de l'embryogenèse. Pour ce faire, nous utilisons une combinaison de modèles mathématiques et de résultats expérimentaux. Dans la première partie, nous utilisons une petite cohorte d'oursins digitaux pour construire une représentation prototypique du lignage cellulaire, reliant les caractéristiques des cellules individuelles avec les dynamiques à l'échelle de l'embryon tout entier. Ce modèle probabiliste multi-niveau et empirique repose sur les symétries des embryons et sur les identités cellulaires; cela permet d'identifier un niveau de granularité générique pour observer les distributions de caractéristiques cellulaires individuelles. Le prototype est défini comme le barycentre de la cohorte dans la variété statistique correspondante. Parmi plusieurs résultats, nous montrons que la variabilité intra-individuelle est impliquée dans la reproductibilité du développement embryonnaire. Dans la seconde partie, nous considérons les mécanismes sources de variabilité au cours du développement et leurs relations à l'évolution. En nous appuyant sur des résultats expérimentaux montrant une pénétrance incomplète et une expressivité variable de phénotype dans une lignée mutante du poisson zèbre, nous proposons une clarification des différents niveaux de variabilité biologique reposant sur une analogie formelle avec le cadre mathématique de la mécanique quantique. Nous trouvons notamment une analogie formelle entre l'intrication quantique et le schéma Mendélien de transmission héréditaire. Dans la troisième partie, nous étudions l'organisation biologique et ses relations aux trajectoires développementales. En adaptant les outils de la topologie algébrique, nous caractérisons des invariants du réseaux de contacts cellulaires extrait d'images de microscopie confocale d'épithéliums de différentes espèces et de différents fonds génétiques. En particulier, nous montrons l'influence des histoires individuelles sur la distribution spatiales des cellules dans un tissu épithélial
We propose in this thesis to characterize variability quantitatively at various scales during embryogenesis. We use a combination of mathematical models and experimental results. In the first part, we use a small cohort of digital sea urchin embryos to construct a prototypical representation of the cell lineage, which relates individual cell features with embryo-level dynamics. This multi-level data-driven probabilistic model relies on symmetries of the embryo and known cell types, which provide a generic coarse-grained level of observation for distributions of individual cell features. The prototype is defined as the centroid of the cohort in the corresponding statistical manifold. Among several results, we show that intra-individual variability is involved in the reproducibility of the developmental process. In the second part, we consider the mechanisms sources of variability during development and their relations to evolution. Building on experimental results showing variable phenotypic expression and incomplete penetrance in a zebrafish mutant line, we propose a clarification of the various levels of biological variability using a formal analogy with quantum mechanics mathematical framework. Surprisingly, we find a formal analogy between quantum entanglement and Mendel’s idealized scheme of inheritance. In the third part, we study biological organization and its relations to developmental paths. By adapting the tools of algebraic topology, we compute invariants of the network of cellular contacts extracted from confocal microscopy images of epithelia from different species and genetic backgrounds. In particular, we show the influence of individual histories on the spatial distribution of cells in epithelial tissues

Information seeking and information avoidance are the mechanisms humans natural used for coping with uncertainties and adapting to environmental stressors. Uncertainties are rooted in knowledge gaps. In social sciences, the relationship between knowledge gaps and perceived risk have received little attention. A review of the information science literature suggests that few studies have been devoted to the investigation of the role of this relationship in motivating information-seeking behavior. As an effort to address the lack of theory building in the field of information science, this study attempts to construct a model of information seeking under risk (MISR) by examining the relationships among perceived risk, knowledge gap, fear arousal, risk propensity, personal relevance, and deprivation and interest curiosity as antecedents to motivation to seek information. An experimental approach and a scenario-based survey method are employed to design the study. Partial least square structural equation modeling (PLS-SEM) analysis was conducted to test the relationships in the proposed model. Perceived risk was found to be a highly significant predictor of information seeking in moderately high-risk situations. Similarly, personal relevant has a significant negative effect on perceived risk and its interaction with knowledge gap motivates information seeking.

This thesis, which is a continuation of the previous Bachelor thesis, is dedicated to the study of polyelectrolyte complexes between hyaluronan (HA) and bovine serum albumin (BSA). Interactions between HA and BSA and a formation of complexes were studied by SEC-MALLS method, where a molar mass, a root mean square (rms) radius, a hydronamic radius and an intrinsic viscosity of particles of the system were defined. Furthermore the interactions were studied by calorimetric measurement ITC, where thermodynamic character of complex formation was determined. Additionally, dynamic and electrophoretic light scattering methods (DLS and ELS) were applied, where hydrodynamic radius and a value of the zeta potential were defined. Also the effect of higher temperature on the character and complex formation was examined by SEC-MALLS and ITC measurements. The interactions were confirmed at any of the used media, but with different efficiency. It was also proved that complexes become smaller in their radii and viscosity with growing BSA concentration. Furthermore it was proved, that the high ionic strength hinders surface charges of HA and BSA molecules and minimizes their mutual interactions. At the higher ionic strength the radii of the complexes, their intrinsic viscosity and zeta potential are increased. The higher temperature has only minimal effect on the formation of the complexes.

Apesar de serem intensamente estudados em muitos países que caminham na vanguarda do conhecimento, os métodos sem malha ainda são pouco explorados pelas universidades brasileiras. De modo a gerar uma maior difusão ou, para a maioria, fazer sua introdução, esta dissertação objetiva efetuar o entendimento dos métodos sem malha baseando-se em aplicações atinentes à mecânica dos sólidos. Para tanto, são apresentados os conceitos primários dos métodos sem malha e o seu desenvolvimento histórico desde sua origem no método smooth particle hydrodynamic até o método da partição da unidade, sua forma mais abrangente. Dentro deste contexto, foi investigada detalhadamente a forma mais tradicional dos métodos sem malha: o método de Galerkin sem elementos, e também um método diferenciado: o método de interpolação de ponto. Assim, por meio de aplicações em análises de barras e chapas em estado plano de tensão, são apresentadas as características, virtudes e deficiências desses métodos em comparação aos métodos tradicionais, como o método dos elementos finitos. É realizado ainda um estudo em uma importante área de aplicação dos métodos sem malha, a mecânica da fratura, buscando compreender como é efetuada a representação computacional da trinca, com especialidade, por meio dos critérios de visibilidade e de difração. Utilizando-se esses critérios e os conceitos da mecânica da fratura, é calculado o fator de intensidade de tensão através do conceito da integral J.
Meshless are certainly very researched in many countries that are in state of art of scientific knowledge. However these methods are still unknown by many brazilian universities. To create more diffusion or, for many people, to introduce them, this work tries to understand the meshless based on solid mechanic applications. So basic concepts of meshless and its historic development are introduced since its origin, with smooth particle hydrodynamic until partition of unity, its more general form. In this context, most traditional form of meshless was investigated deeply: element free Galerkin method and also another different method: point interpolation method. This way characteristics, advantages and disadvantages, comparing to finite elements methods, are introduced by applications in analyses in bars and plates in state of plane stress. This work still researched an important area of meshless application, fracture mechanical, to understand how a crack is computationally represented, particularly, with visibility and diffraction criterions. By these criterions and using fracture mechanical concepts, stress intensity factor is calculated by J-integral concept.

Magister Scientiae - MSc (Chemistry)
Pollutants such as polycyclic aromatic hydrocarbons (PAHs) are known for their toxic effects which may lead to the cause of degenerative diseases in both humans and animals. PAHs are widespread in the environment, and may be found in water, food, automotive industry and petrochemical industries to name but a few sources. Literature reports have highlighted industrial workplace exposure to PAHs as a leading cause for development of cancer in workers. Particularly, workers in the petrochemical industry are adversely affected and the incidence of skin and lung cancer in this population group is high. The United States of America in its guidelines developed by environmental protection agency (EPA) has identified 18 PAHs as priority pollutants. Among these are anthracene, benzo[a]pyrene and pyrene which have been selected as the focal point of this study due to their significance in the petrochemical industry. Due to the carcinogenic and mutagenic properties reported in literature for certain PAHs, there have been monitoring procedures taken in most countries around the world. The commonly used analytical methods for the detection of PAHs from industrial samples are high performance liquid chromatography (HPLC) coupled to fluorescence detection, membrane filtration, ozonation and reverse osmosis. Analysis of PAHs from the petrochemical industry is typically performed by HPLC method as well as sono-degredation in the presence of oxygen and hydrogen peroxide.

碩士
國立中山大學
海洋生物科技暨資源學系研究所
97
Complete DNA sequences were determined for the mitochondrial (mt) genomes of the sea anemones, Mesactinia genesis （20,544 bp）, Heteractis aurora (19,800 bp) and partial mtDNA between cox2 and nad4 of the Calliactis sp. (3,713 bp). In addition, complete mtDNA sequences were determined for the sea squirt, Eudistoma gilboviride (14,203 bp). The circular, sea anemones genomes contain the genes for 13 energy pathway proteins and two ribosomal RNAs and two transfer RNAs. H. aurora contains a previously undescribed ORF between the cox2 and nad4 genes encoding a putative protein of 646 amino acids. In M. geneisis and Calliactis sp. encodes two separate smaller ORFs of 259 and 243 as well as 269 and 345 in the corresponding regions, respectively. Possible control region of the mitochondrial genomes of M. geneisis and H. aurora were identified in the intergenic region 13. The sea squirt genomes contain the genes for 11 energy pathway proteins and two rRNAs and 22 tRNAs. All genes are encoded by the heavy strand, except for trnM, trnK, and trnV, which are encoded by the light strand. The ascidians showed frequent and extensive gene rearrangement. The gene order in E. gilboviride are very much different from the other ascidians mt-genome. The E. gilboviride mtDNA does not encode the nad6 and a tpyical atp8. Molecular phylogenetic analyses based on nucleic acid and amino acid sequences of the deuterostome (echinoderms, chordate and Xenoturbella), and cnidaria coincide with the morphological characters.

碩士
國立臺灣海洋大學
應用經濟研究所
95
After more than thirty years of endeavors, Taiwanese squid fishery has established its status in the deep sea fishery. However, facing rising oil price, unstable resources, high fishing access fee, and competition from a large number of Chinese fishing vessels, the industry has been confronted with extreme crisis and challenge for its survival. Using cost-benefit cross tabulation analysis and direct interviews with business owners, this study investigates the major difficulty of Taiwan’s deep sea squid fishery and searches for solutions. The main sources of data come from “Economic Survey of Taiwan Deep Sea Fishery” and personal interviews of ship owners in Kaohsiung Qianchen fishing port. Cost-benefit analysis is utilized to analyze important cost items such as operating expenses in fishing, labor, sales, management and maintenance costs of the vessel and its equipment. Research results are as follows: 1) Operating expenses account for the greatest portion of the total cost in both fishing solely squid and fishing squid with saury as by catch, reaching 51.8% and 52.2%, respectively, while labor expenses, the second largest item, account for 24.4% and 23.0% respectively. The above two items constitute as much as 75% of the total cost. 2) In terms of profitability, Taiwan squid fishing vessels did not do well in 2003, 2004 and 2005. At best, they were only able to recover fixed cost. 3) Ship owners generally expect government to take measures to assist them in promotion of market expansion and fishery cooperation with the coastal nations owning the resources in order to lessen the difficulty in operation.

碩士
國立臺灣海洋大學
應用經濟研究所
93
Abstract Deep-sea Squid fishery is an important fisheries industry in Taiwan. However, in the recent years, it faces with the problem of increasing production costs which resulting in the lost of compatibility in the world fishery. It is important to control the production cost and raise the efficiency of operation. Therefore this paper aims to analyze the cost-benefit structure of the industry, the key factors of increase of the production cost. The study also uses SUR as a method to estimate the cost function of the industry so as to find out the possible solution for the cost control. The paper also deals with a SWOT analysis on the industry. With the study of the paper, we obtain the major finding as follows. 1. The major expense of the deep-sea Squid fishing industry is the expense of traveling on the sea, which account for 41.14% of the total cost. Within the cost fuel expense ranks the first item in the total. 2. The average net profit of the industry is about 1.52% which is quite low when compare to other fishing industries. 3. Base on an empirical study of cost function, fishing boats in the size of 900-1000 ton is more costly than others. Base on Allen’s partial elasticity of substitution, we also find that the factors between capital and labor are in substitution; however labor cost and the expense of traveling in the sea are in the relation of complementary. Which means that in order to control the production cost it is important to shrink the labor cost by improve its automation for the fishing boats. In order to raise their profit, it is also important to improve their marketing efforts.

Tese de mestrado em Ecologia Marinha, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2017
O oceano constitui grande parte do planeta, acomodando cerca de 1 368 milhões Km3 de água, providencia mais espaço que todos os habitats terrestres. Apesar da maioria da biodiversidade marinha se encontrar na zona fótica e menos profundas, uma grande variedade vive nas partes mais profundas e sem luz. Em algumas partes do oceano, entre os 10 e os 1 300m, existem zonas de oxigénio mínimo (ZOM). Estes habitats pelágicos apresentam condições estáveis de níveis baixos e persistentes de oxigénio e baixas temperaturas ao longo de vastas áreas. Estes habitats resultam de uma combinação de uma fraca ventilação assim como pouca circulação da água. A maioria das ZOM exibe um perfil de oxigénio semelhante, mas os níveis de oxigénio, espessura e a profundidade de ocorrência podem variar regionalmente. No Atlântico Tropical Oriental, a uma profundidade entre os 200m a 800m, existe uma zona mínima de oxigénio localizada entre o sistema da Corrente Equatorial (a Sul) e a Corrente Equatorial Norte (a Norte). Aqui, o perfil de oxigénio tem dois mínimos a cerca de 70m e 400m de profundidade, com o mínimo mais proeminente entre o Senegal e a Ilha de Cabo Verde. Os cefalópodes (classe Cephalopoda) podem ser encontrados em todos os oceanos do mundo, desde águas costeiras ao mar profundo, e algumas espécies conseguem viver em condições extremas, como as fontes hidrotermais e as ZOM. A maioria destes moluscos são predadores oportunistas com altas taxas de crescimento, uma única época de reprodução e uma esperança média de vida curta nas zonas costeiras. No mar profundo, estas características biológicas são bastante diferentes, dado que as suas capacidades locomotoras e requisitos metabólicos são mais reduzidos. De uma forma geral, os cefalópodes desempenham um papel fundamental nos ecossistemas marinhos, uma vez que são uma fonte primária de alimento para muitos predadores marinhos, como peixes, mamíferos marinhos ou aves marinhas. Os cranchídeos (família Cranchiidae) estão entre as lulas mais abundantes do mundo, de grande diversidade morfológica em ambientes pelágicos. A maioria delas têm uma aparência transparente (por isso designadas também por lulas de vidro) dado possuírem grandes cavidades celómicas cheias de fluido amoniacal neutro e de baixa densidade, que lhes confere flutuabilidade neutra. Embora a sua morfologia e anatomia estejam bem estudadas, e de serem muito abundantes, pouco se sabe sobre a sua biologia e ecologia. Muitas das espécies de cranchídeos passam grande parte de sua vida em águas onde quase não há luz ou em completa escuridão. A maioria desses pequenos animais não depende da velocidade para escapar de predadores, mas sim de outras estratégias defensivas, - a sua transparência, que sob condições de iluminação adequadas, as tornam praticamente invisíveis. A poluição marinha tornou-se um problema muito grave durante as últimas décadas, devido aos seus impactos na biodiversidade e no funcionamento dos ecossistemas. A presença de concentrações acima do normal de contaminantes já foi detetada em vários tipos de habitats marinhos, nomeadamente no mar profundo, onde a preocupação tem vindo a aumentar devido à possibilidade de este, devido à sua dimensão, se poder tornar no maior depósito para tais elementos. A bioacumulação tem sido amplamente estudada em muitos organismos marinhos e demonstrou-se que os moluscos, como os cefalópodes, têm a capacidade de acumular altos níveis de contaminantes. As maiores concentrações determinadas são o carbono, hidrogénio, azoto, oxigénio e enxofre, que são elementos estruturais. Outros elementos encontrados podem ser essenciais, cujo papel biológico é conhecido, como ferro, cobre, zinco, iodo, manganês, selénio ou flúor. Os não essenciais, não têm um papel conhecido nas funções fisiológicas, como ocorre com mercúrio, chumbo e cádmio. Embora existam estudos sobre a acumulação de elementos em cefalópodes, a maioria está focada em espécies comerciais. Entre essas espécies, foram geralmente registados altos níveis de metais, como o cádmio, o cobre e o zinco, tornando os cefalópodes uma potencial via de transporte de contaminantes para níveis tróficos superiores. A absorção de contaminantes por organismos marinhos pode ocorrer a partir da água, incluindo partículas em suspensão, alimentos e sedimentos. Outros fatores, como a disponibilidade de elementos na água, período de exposição, temperatura, tamanho, sexo, estágio de maturidade e local de captura, também são importantes na acumulação de metais nos tecidos destes organimsos. É importante referir que dado que os cefalópodes apresentam uma vida curta e uma alta acumulação de contaminantes, estes organismos podem refletir as condições actuais do ambiente onde vivem e serem utilizados como indicadores de contaminação ambiental. Embora não haja informações sobre contaminantes nos cranchídeos, existe informação sobre outras espécies de cefalópodes, incluindo outras lulas oceânicas. A maioria dos estudos mostrou a capacidade dos cefalópodes de concentrar Zn, Cu e Cd na glândula digestiva mesmo em ambientes com baixa disponibilidade. Neste contexto, o objetivo desta dissertação, foi determinar, pela primeira vez, as concentrações de alguns elementos (V, Cr, Co, Ni, Cu, Zn, As, Se, Cd e Pb) nos tecidos (glândula digestiva, manto e tentáculos) de nove espécies de cranchídeos, da ZOM de Cabo Verde. As lulas foram apanhadas na zona económica exclusiva de Cabo Verde, em oito estações de amostragem, através da utilização de redes pelágicas MOCNESS e IKMT em diferentes profundidades. Os indivíduos capturados foram identificados até à espécie (quando possível) e preservados em azoto líquido abordo do RV Maria S. Merian e depois transferidas para -80ºC no laboratório. Os indivíduos foram dissecados de modo a separar o manto, os tentáculos e a glândula digestiva. Neste trabalho, foram detectadas diferenças significativas entre espécies de cranchídeos e entre os diferentes tecidos analisados. De uma forma geral, os elementos na glândula digestiva variaram entre os 0,070 e 17 μg g-1 peso seco, com as concentrações variando da seguinte forma decrescente: Zn > Cd > As > Cu > V > Se > Co > Cr > Ni > Pb. No manto variaram entre os 0,070 e 28 μg g-1 peso seco, com as concentrações variando da seguinte forma decrescente: Zn > Cu > Cr > As > V > Ni > Se > Cd > Pb > Co. Nos tentáculos, os contaminantes variaram entre os 0,13 e os 24 μg g-1 peso seco, com as concentrações variando da seguinte forma decrescente: Se > Zn > As > Cu > Cr> Ni > V > Cd > Co > Pb. Estes resultados em comparação com os de outros grupos de cefalópodes (nomeadamente chocos, polvos e outras lulas pelágicas) mostraram que as espécies pelágicas (lulas) apresentavam menores concentrações de Cd do que as espécies bentónicas (polvos) ou nectobentónicas (chocos). Essas diferenças podem ser atribuídas às diferentes concentrações de Cd nas suas presas, uma vez que as presas bentônicas (crustáceos e bivalves) têm maiores concentrações de Cd, do que os peixes que são presas preferenciais de espécies pelágicas. Em relação às espécies nectobentónicas e bentónicas, os sedimentos também podem ser uma via de acumulação - embora a transferência direta seja menor, podem atuar como uma fonte indireta de contaminantes. Por último, as diferenças com os nautilus podem estar relacionadas com diferentes tempos de vida, uma vez que os nautilus vivem entre os 10 e os 15 anos, enquanto os Coleoids (choco, lulas e polvos) vivem entre 1 a 3 anos. Embora a expectativa de vida da maioria dos cranchídeos não seja conhecida, não é provável que os indivíduos estudados atinjam essas idades. É importante notar que os músculos dos cranchídeos apresentaram maior variação e uma maior concentração do que as outras espécies de cefalópodes. Estes resultados não eram esperados e levanta a questão porque é que os cranchídeos concentram elevados níveis de alguns elementos nestes tecidos. A capacidade dos cefalópodes para concentrar altos níveis de metais sem um sinal de toxicidade, está associada a eficientes processos de desintoxicação que permitem reter os elementos de forma não metabolicamente disponível, limitando assim a sua toxicidade. Neste contexto, a glândula digestiva é um órgão complexo envolvido em várias funções, como digestão, secreção e desintoxicação (entre outros). Por ser considerado um tecido de armazenamento, é também um órgão-chave para a desintoxicação. Não surpreendentemente, mas com algumas exceções (por exemplo, Hg e As), a maioria dos contaminantes são encontrados em concentrações mais elevadas neste tecido. Pensa-se que inicialmente os contaminantes estão ligados a proteínas solúveis, o que implica que as células da glândula digestiva provavelmente estarão envolvidas na desintoxicação dos contaminantes. Esta associação com proteínas citosólicas, inibe as interações tóxicas de iões metálicos com locais de ligação sensíveis (proteínas, moléculas ou estruturas celulares). Além disso, uma vez que os metais como Ag, Cd, Cu, Hg e Zn têm uma alta afinidade para as metalotioninas, pensa-se que estas desempenham um papel fundamental na homeostasia dos metais essenciais, bem como um papel importante na tolerância dos organismos a elementos não-essenciais. Estudos anteriores mostraram que não é só o Cd, mas também outros contaminantes, como Co, Cr, Ni e V, são encontrados em concentrações mais elevadas na glândula digestiva do que no músculo. No entanto, nos cranchídeos, e apesar de o Co ter apresentado concentrações mais elevadas na glândula digestiva, o V, Cr e Ni apresentaram valores mais elevados no manto. Quanto às diferenças entre manto e tentáculos, estas podem ser devido a diferentes composições proteicas e respectivos sistemas enzimáticos, podendo explicar os resultados obtidos com os cranchídeos Em suma, o fato das lulas de vidro, que prosperam em ambientes pelágicos profundos, exibirem concentrações de contaminantes semelhantes aos encontrados nos cefalópodes costeiros (cujos habitats estão sujeitos a uma maior intervenção humana), é inesperado. Estes dados corroboram a ideia corrente de que esses ambientes remotos estão-se a tornar o principal acumulador de contaminantes no planeta.
Trace elements are persistent and have been detected in a wide range of environments, including the deep-sea, where the concern is increasing, as it might act as a global sink for them. One group of cephalopods that thrive in such harsh environments, including the mesopelagic oxygen minimum zones, are the cranchiid (glass) squids. Although their anatomy and morphology is well understood, little is known about their biology and ecology. Elemental bioaccumulation has been greatly studied in many marine organisms and it has been shown that cephalopods have the ability to accumulate high levels of elements. The uptake of trace elements can occur from water, including suspended particulate matter, food and sediments. Because cephalopods display a short life span and high accumulation of trace elements, these characteristics may clearly reflect the ambient life conditions and indicators of environmental contamination. Yet, up to our knowledge, there is no information about trace elements in the deep cranchiid squids. Within this context, the aim of the present dissertation was to determined, for the first time, the concentrations of V, Cr, Co, Ni, Cu, Zn, As, Se, Cd and Pb in the digestive gland, mantle and tentacles of nine different cranchiid squids from the Cape Verde Exclusive Economic Zone in the Eastern Atlantic Ocean. Concomitantly, a comprehensive comparison with trace elements obtained in shallow-living cephalopod species (including cuttlefish, octopods and other squids) was also conducted. In general, trace elements in cranchiid digestive gland ranged between 0.07 and 17 μg-1 dw, with the following average concentrations in descending order: Zn > Cd > As > Cu > V > Se > Co > Cr > Ni > Pb. In the mantle ranged between 0.07 and 28 μg g-1 dw, with the following average concentrations in descending order: Zn > Cu > Cr > As > V > Ni > Se > Cd > Pb > Co. In the tentacles, trace elements ranged between 0.13 and 24 μg g-1 dw, with the following average concentrations in descending order: Se > Zn > As > Cu > Cr> Ni > V > Cd > Co > Pb. The high Cd levels in cranchiid squids may be related to the enriched environment around Cape Verde islands, with dissolved Cd being reinjected in the water column by the upwelling of subsurface waters. Additionally, another route of contamination could be from the Saharian dust deposition, which represents an important source of trace elements (Co, Ni, Zn and Cd) into the Atlantic Ocean. In the present work, it also became evident that benthic cephalopod species showed higher concentrations of Cd than the pelagic conspecifics. These differences could be attributed to distinct trophic ecologies (different trace elements concentrations on their preys). Previous studies have also shown that not only the Cd but also other trace elements, like Co, Cr, Ni and V are found at higher concentrations in the digestive gland (the major storage site and a key organ for detoxification) than in the muscle. These findings were not corroborated here, since while Cd and Co levels were higher concentrations in the digestive gland, V, Cr and Ni have higher concentration values in the mantle. Last, it is worth noting that the fact that glass (transparent) squids that thrive in deep pelagic environments display trace elements concentrations as high as those found in coastalcephalopods, which live in habitats exposed to enhanced anthropogenic forcing, is quite surprising. These findings corroborate the on-going notion that such remote environments are now the major global sink for contaminants in the planet.

Dissertação de mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015
Exotic species have been considered by several authors as the worst threat that can occur to native biodiversity. Due to the lack of information on sea squirts and barnacle invaders in southern Portugal, the first step of this study aims to detect and identify their presence in the ports of the region. A comparison reporting differences between these ports was performed: i) fishing and recreational; ii) port location; iii) sheltered versus unsheltered facilities. The localities of Lagos, Quarteira-Vilamoura, Faro and Olhão were the study areas where seasonal sampling was done. A case study to obtain the total recruitment for the invasive species was also carried out, comparing surfaces and removal of invaders. Higher percentages of invasive species were found (60% for barnacles and 58.3% for sea squirts). The appearance of one invasive gastropod, originating in the West African coast, was reported in European waters the first time. Besides, for barnacle and sea squirt counting, there were significant differences in all comparisons except between seasons for barnacles and type of port for sea squirts. The main differences in the abundance, frequency of occurrence and communities seems to be related with the transit of international vessels, the settlement period and the conditions presented between ports in terms of exposure to the sea. Differences between surfaces during the case study were found, showing wallets as the best surface for sea squirts and cement plates for barnacles in general. Cement can be considered as the best surface for recruitment for the invasive Amphibalanus amphitrite in relation with the huge abundance found. The other two invasive Amphibalanus cf. eburneus and Styela plicata found during the experiment, did not present any preference between surfaces. So in general for the three invasive species of this area the use of cement plate guarantees a high rate of recruitment.

博士
國立臺灣大學
海洋研究所
93
The fisheries acoustic technique, which is capable of directly assessing underwater populations over a large volume of waters in a short time, makes it a powerful tool for fisheries scientists. This paper dealt with the application of such technique to investigate the unexploited Purpleback Flying Squid (Sthenoteuthis oualaniensis) resource in the South China Sea. The results summarized as follows: (1) Mantle Length (ML) survey using especially designed squid jigger, which can cast down to a specific depth with notification of catching a squid specimen, as well as concurrent collection of in situ Target Strength (TS) using EK500 scientific echosounder were carried out and the results show : (i) the larger the ML the stronger the in situ TS; (ii) seasonal mean in situ TS of squid and its corresponding ML are -51.2dB and 15.0cm, in spring (February-April); -48.2dB and 18.9cm appeared in summer (May-July), -49.3dB and 17.1cm in autumn (August-October), -54.1dB and 13.8cm in winter (November-January), respectively. (2) A searching with validation algorithm was developed in this study to acquire the logarithm-linear relationship of in situ TS versus ML of the squid. The results are as follow: for ML from 10cm to 32cm. According to the depth range dispersion echoed by in situ squid TS, squid concentration of nighttime appeared in water column depth of 10-210m in spring and autumn; appeared in depth of 10-160m in summer and winter. (3) A procedure to extract the echo energy of squid signals from the total echo energy was developed, as to filter noises that mainly composed of background noise and. The precision improvement in Volume backscattering Strength (SV) due to such procedure is estimated about 11%. (4) Seasonal mean SV, which is essential for estimating abundance, of the squid obtained in this study show that: -77.9 dB in spring 1999, -70.6 dB in summer 1998, -75.8 dB in autumn 1999 and -72.2 dB in winter 1999. Seasonal mean squid abundance thus derived appeared to be 4.2 in spring; 8.9 in summer; 5.1 in autumn; and 26.1 in winter. (5) Female Gonad Index (GI), which is the ratio of gonad weight to total body weight multiplied by 100, is analyzed in this study. The results show: that GI is a good indicator for female maturation; GI larger than 3 (ML larger than 20cm) indicating a matured female, smaller than 2 (ML smaller than 15cm) indicating immature ones. Squids caught by in situ biological sampling device appeared that all matured in summer and all immatured in winter while both matured and immatured squid present in spring and autumn. (6) Assumed that the population of the Purpleback Flying Squid in the South China Sea was an enclosed stock and under a steady population condition in recent years, the basic population characters of this squid was postulated as follow: the main spawning season occurs in summer; the major detectable recruitment (ML large than 9 cm) occurs in winter with rather high density; yet the survival rate of this recruitment in next spring appeared to be low (about 20%). (7) The total surveyed one-degree square block area, within which biological survey conducted in this study has captured Purpleback Flying Squid, is about . The abundance of Purpleback Flying Squid in the South China Sea is estimated as individuals in summer 1998, which is also the spawning season of this species. The mean body weight of the squid in this season is about 0.3 kg, thus the estimated total standing stock size of this resource was about 1500 thousand metric tons in the offshore regions of the South China Sea.

碩士
國立中山大學
海洋資源學系
82
The deep-sea squid jigging fishery of Taiwan began at 1972 , and the trandational fishing grounds included the New Zealand waters , the northwest Pacific and the southwest Atlantic . The southwest Atlantic was the only squid jigging fishing ground with economic value in 1993 . This study analyzed the profitability and fuel oil average product of 700 ton-class (701-800 tonnage) and 800 ton-class ( 801-1000 tonnage) squid jigging fishery in the southwest Atlantic from 1991 to 1993 . The results were as follows : 1.profitability By means of the present value method , the profitability of 800 ton-class was better than that of 700 ton-class . The reasons were : (1) The average variable cost of the 800 ton-class was about 30-50﹪ higher than that of 700 ton-class , but the former''s fi- shing revenue was about 40-100﹪ higher than the latter''s . (2) Among the direct costs , the fishing oil was the biggest one that averaged 13.51﹪ of the 700 ton-class'' average variable cost. The cooperative license fee was the biggest one that ave- raged 15.56﹪ of the 800 ton-class'' average variable cost. As for the indirect costs , the depreciation was the bigg- est one between 700 and 800 ton-class''. (3) 800 ton-class'' average fish price was about 31.7﹪ higher than break-even price , and 700 ton-class'' had only about 3.7﹪. (4) 800 ton-class'' average fish product was about 33﹪ higher than break-even product , which was much better than 4﹪ higher of 700 ton-class''. 2.fuel oil average product Having analyzed the data , this study got the conclusion that 800 ton-class was superior in fuel oil average product to 700 ton-class due to the following reason : 800 ton-class'' average value of fuel oil product averaged 10.24﹪ , which was higher than 700 ton-class'' 8.63 .

碩士
國立臺灣海洋大學
環境生物與漁業科學學系
103
Neritic squid is a short-lived species of which usually vulnerable to environmental conditions and shows great variation in annual abundance. Swordtip squid, Uroteuthis (Photololigo) edulis, is a neritic squid distributed in subtropical and tropical coastal water in the Indo-western Pacific. This species plays a critical role in marine ecosystems and also an important fisheries resource. Production of neritic squid for the neritic and coastal fisheries of Taiwan ranged from 3,398 to 19,381 tons during 1986-2013, of which production from the southern East China Sea (SECS, production of New Taipei city and Keelung city) accounted of 52%. The squids are targeted by torch-light net and trawl fleet. The SECS is an important fishing grounds for neritic squid fishery of Taiwan, however, the production of neritic squid was decreasing in recent years. Studies on squid stock assessment and abundance trend is scarce in this region. In this study, catch data of neritic squid fleet (mainly torch-light net fleet) from the SECS from 2002 to 2013 are analyzed. The fishing efforts of individual vessel are standardized by comparing relative CPUE of each paired-vessel in the same day and location. Abundance of the neritic squid is estimated by the depletion method. Annual number of sample vessels range from 9 to 32 with a total of 19,007 records, and the fleet operated around 23°~31.5 °N, 119~127.5 °E. The number of vessels can be directly compared with the standard vessel (level 1) range from 2 (in 2004) to 19 (in 2009), while indirectly compared with the standard vessel (level 2) range from 0 (in 2003, 2005-2006 and 2013) to 9 (2010). Proportion of standardized vessels ranges from 44% (in 2004) to 90% (in 2010). The estimated fishing powers of each vessel ranged from 0.03 to 6.25. The adjusted CPUEs are lower than the nominal CPUE for at least 8 years during 2002-2013. The abundance trends are similar for the nominal and the adjusted CPUE: increased from 2002 to 2005, decreased from 2005 to 2008, and increased again after 2009. The catch data (in weight) are converted to catch in individuals by historical biological data and perform the depletion method. The catchability coefficients are highly variable annually (0.57 to 12.92). The annual fishing mortality (F) ranges from 1.50 (in 2009) to 15.75 (in 2011). The annual initial population size ranges from 0.76 million (in 2002) to 11.1 million (in 2010). The annual proportional escapement, assuming weekly natural mortality at 0.03, ranges from 36% (in 2006) to 96% (in 2008) with an average of 75%. The escapement biomass is 22,655.6 to 3,756,461.03 tons. These results suggest that the abundance of swordtip squid in the SECS was kept upper level, although limited number of sample vessel could hinder actual situation. Stock abundance and distribution pattern of short-lived species are vulnerable to environmental conditions, and usually response quickly. Therefore, to increase number of sample vessels and continue monitoring III variation in fleet and catch may improve the results of stock assessment for neritic squids which could support the basic information for strategies of fishing management planning.

碩士
國立高雄海洋科技大學
漁業生產與管理研究所
102
The amount of foreign seafarers has gradually increased in recent years. They are hired either based on Employment Service ACT or employed by the vessel owner himself, which means the fishery industries become more globalized. This phenomenon shows a remarkable trend that the foreign seafarers are more important. The results of this study were conducted from questioned and interviewed the boat owners about seafarers’ performance who worked on squid and saury boats. The conclusions reveal that the owners regard salary, efforts and obedience as the hiring factors, they are willing to offer proper accommodation and bonus if these employees meet anticipations as well. The Philippine, Indonesian and Vietnamese seafarers’ work attitude have significant difference on employment willingness. Setting a work performance standard not only can compare effectiveness of seafarers but also be able to realize what are the major hiring elements to reduce conflicts and arguments among seafarers. It provides a more stable and safe work environment on the sea for foreign seafarers.

Natural cycles of environmental variability and long-term deoxygenation in the ocean impose oxygen deficiency (hypoxia) on marine communities. My research exploits a naturally occurring hypoxia cycle in Saanich Inlet, British Columbia, Canada where I combined spatial surveys with remotely operated vehicles, ecological time-series from the subsea cabled observatory VENUS, and lab-based respirometry experiments to examine the influence of seasonally variable oxygen conditions on epibenthic communities. In situ oxygen thresholds established for dozens of fish and invertebrate species in this system show they naturally occur in lower oxygen levels than what general lethal and sublethal thresholds would predict. Expansion of hypoxic waters induced a loss of community structure which was previously characterized by disjunct distributions among species. Communities in variable hypoxia also have scale-dependent structure across a range of time scales but are primarily synchronized to a seasonal oscillation between two phases. Time-series revealed timing of diurnal movement in the slender sole Lyopsetta exilis and reproductive behavior of squat lobster Munida quadrispina in the hypoxia cycle. Hypoxia-induced mortality of sessile species slowed the rate of community recovery after deoxygenation. The 10-year oxygen time-series from VENUS, revealed a significant increase in the annual low-oxygen period in Saanich Inlet and that deoxygenation has occurred in this system since 2006. Differences in the critical oxygen thresholds (O2crit) and standard metabolic rates of key species (spot prawn Pandalus platyceros, slender sole, and squat lobster) determined the lowest in situ oxygen at which populations occurred and explained disproportionate shifts in distributions and community respiration. Finally, a meta-analysis on global O2crit reported for crustaceans showed that hypoxia tolerance differs among major ocean basins. Long-term trends of deoxygenation suggest a future regime shift may occur when the duration at which a system remains below critical oxygen levels exceeds the time needed for communities to recover. Species-specific traits will determine the critical threshold and the nature of the community response in systems influenced by variable states of oxygen deficiency. However, oceanographic and evolutionary history provides context when determining the regional response of benthic communities influenced by rapidly changing environments.
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Text in English
Developments in Internet technology and pervasive computing over the past two and half decades have resulted in a variety of Web-based applications (WBAs) that provide products and services to online users or customers. The Internet is used not only to transfer information via the web but is increasingly used to provide electronic services including business transactions, information-delivery and social networking, as well as e-government, e-health and e-learning. For such organisations, e-service quality, usability and user experience are considered to be critical determinants of their products’ or services’ success. Many studies to model these three concepts separately have been undertaken as part of broader studies of software quality or service quality modelling. However, to the current researcher’s knowledge, none of the studies have focussed on proposing an evaluation model that integrates and combines the three of them. This research is an effort to fill that gap. The primary purpose of this mixed-methods research was to develop a conceptual integrated model for evaluating e-service quality, usability and user experience (e-SQUUX) of WBAs and then contextualise it to evaluation of a University web portal (UWP). This was undertaken using an exploratory sequential research design. During a qualitative phase, an extensive extensive systematic literature review of 264 relevant sources relating to dimensions of e-service quality, usability and user experience, was undertaken to derive an integrated conceptual e-service quality, usability and user experience (e-SQUUX) Model for evaluating WBAs. The model was then empirically refined through a sequential series of validations, thus developing various versions of the e-SQUUX Model. First, it was content validated by a set of four expert reviewers. Second, during the quantitative phase, in the context of a University web portal, a questionnaire survey was conducted that included a comprehensive pilot study with 29 partipants, prior to the main survey. The main survey data from 174 particiapants was used to determine a validated model, using Exploratory factor analysis (EFA), followed by producing a structural model, using partial least square – structural equation modelling (PLS-SEM). This version consisted of the components of the final e-SQUUX Model. Consequently, the research enriches the body of knowledge on IS and HCI by providing the e-SQUUX Model as an evaluation tool. For designers, developers and managers of UWPs, the model serves as a customisable set of evaluation criteria and also provides specific recommendations for design. In line with the Exploratory sequential design of mixed methods research, the findings of the qualitative work in this research influenced the subsequent quantitative study, since the potential Likert-scale questionnaire items were derived from the definitions and meanings of the components that emanated from the qualitative phase of the study. Consequently, this research is an exemplar for developing an integrated evaluation model for specific facets or domains, and of its application in a particular context, in this case, a University web portal. Keywords: e-service quality, usability, user experience, evaluation model, integrated model, exploratory factor analysis, partial least square – structural equation modelling (PLS-SEM), mixed methods research, Exploratory sequential design, quantitative study, qualitative study, validation, Web-based applications, University web portal
Information System
Ph D. (Information Systems)