Epitypification and phylogeny of Colletotrichum acutatum J.H. Simmonds

Simmonds introduced Colletotrichum acutatum in 1965, validated in 1968, with a broad concept, as demonstrated by the selection of several type specimens from a range of hosts. This has created some confusion in the species concept and identification of C. acutatum. There are no viable ex-type cultures of C. acutatum and furthermore there are no existing cultures of C. acutatum on Carica papaya from the type locality in south-east Queensland. The application of molecular phylogenetic studies to isolates of C. acutatum is only meaningful if the taxonomy is stable and species are properly named. In order to clarify the species concept of C. acutatum, an isolate of Colletotrichum acutatum from Carica papaya from Yandina in Southeast Queensland (Australia) is designated as an epitype. A detailed morphological description is provided. Phylogenies based on a combined ITS and beta-tubulin gene analysis indicate that C. acutatum bears close phylogenetic affinities to C. gloeosporioides and C. capsici. Results also indicate that C. acutatum is monophyletic and there is a close relationship between the epitype and other Australian C. acutatum isolates from Carica papaya. Molecular data, however did not provide further evidence to properly elucidate the taxonomie affinities of C. acutatum especially the holotype and epitype. Our studies indicate that given the complexity of the genus Colletotrichum, there is a need to check previously described type specimens and redesign neotypes where necessary in order to clarify taxonomie uncertainties.

Testing approximate theories of first-order phase transitions on the two-dimensional Potts model

The two-dimensional,q-state (q>4) Potts model is used as a testing ground for approximate theories of first-order phase transitions. In particular, the predictions of a theory analogous to the Ramakrishnan-Yussouff theory of freezing are compared with those of ordinary mean-field (Curie-Wiess) theory. It is found that the Curie-Weiss theory is a better approximation than the Ramakrishnan-Yussouff theory, even though the former neglects all fluctuations. It is shown that the Ramakrishnan-Yussouff theory overestimates the effects of fluctuations in this system. The reasons behind the failure of the Ramakrishnan-Yussouff approximation and the suitability of using the two-dimensional Potts model as a testing ground for these theories are discussed.

Mapping and characterisation of the inter-reefal benthic assemblages of the Torres Strait

A comprehensive survey of the benthic assemblages of the Torres Strait was conducted in order to provide critical baseline information for regional marine planning, assessing the environmental sustainability of fisheries and understanding the ecosystems of the region. Over 150 sites throughout the region were sampled with a modified prawn trawl, towed underwater video, pipe dredge and epibenthic sled. This manuscript provides a broad overview of the activities undertaken and data collected. Two thousand three hundred and seventy-two different nominal species were sampled by the trawl and sled, only 728 by both gears. The towed video was not able to provide the same level of taxonomic resolution of epibenthic taxa, but was particularly useful in areas where the seabed was too rough to be sampled. Data from the trawl, sled and video were combined to characterise the epibenthic assemblages of the region. Data from the towed video was also used to provide a characterisation of the inter-reefal benthic habitats, which was then analysed in combination with physical covariate data to examine relationships between the two. Levels of mud and gravel in the sediments, trawling effort and seabed current stress were the covariates most significantly correlated with the nature of the seabed habitats.

The role of transition metal oxides in the decomposition and explosion of arylammonium perchlorates

The influence of MnO2, CuO, and NiO on the thermal decomposition and explosivity of arylammonium perchlorates has been studied by differential thermal analysis (DTA) and explosive sensitivity measurements. The metal oxides considerably sensitize both decomposition and explosion and the sensitizing effect is in the order NiO < CuO < MnO2. The accelerated decomposition or explosion seems to occur via the formation of an intermediate, metal perchlorate arylamine complex. The experimental evidence for the mechanism put forward has been included.

Exploring the experiences and conceptions of good teaching in higher education : Development of a questionnaire for assessing students' approaches to learning and experiences of the teaching-learning environment

The aim of this dissertation was to adapt a questionnaire for assessing students’ approaches to learning and their experiences of the teaching-learning environment. The aim was to explore the validity of the modified Experiences of Teaching and Learning Questionnaire (ETLQ) by examining how the instruments measure the underlying dimensions of student experiences and their learning. The focus was on the relation between students’ experiences of their teaching-learning environment and their approaches to learning. Moreover, the relation between students’ experiences and students’ and teachers’ conceptions of good teaching was examined. In Study I the focus was on the use of the ETLQ in two different contexts: Finnish and British. The study aimed to explore the similarities and differences between the factor structures that emerged from both data sets. The results showed that the factor structures concerning students’ experiences of their teaching-learning environment and their approaches to learning were highly similar in the two contexts. Study I also examined how students’ experiences of the teaching-learning environment are related to their approaches to learning in the two contexts. The results showed that students’ positive experiences of their teaching-learning environment were positively related to their deep approach to learning and negatively to the surface approach to learning in both the Finnish and British data sets. This result was replicated in Study II, which examined the relation between approaches to learning and experiences of the teaching-learning environment on a group level. Furthermore, Study II aimed to explore students’ approaches to learning and their experiences of the teaching-learning environment in different disciplines. The results showed that the deep approach to learning was more common in the soft sciences than in the hard sciences. In Study III, students’ conceptions of good teaching were explored by using qualitative methods, more precisely, by open-ended questions. The aim was to examine students’ conceptions, disciplinary differences and their relation to students’ approaches to learning. The focus was on three disciplines, which differed in terms of students’ experiences of their teaching-learning environment. The results showed that students’ conceptions of good teaching were in line with the theory of good teaching and there were disciplinary differences in their conceptions. Study IV examined university teachers’ conceptions of good teaching, which corresponded to the learning-focused approach to teaching. Furthermore, another aim in this doctoral dissertation was to compare the students’ and teachers’ conceptions of good teaching, the results of which showed that these conceptions appear to have similarities. The four studies indicated that the ETLQ appears to be a sufficiently robust measurement instrument in different contexts. Moreover, its strength is its ability to be at the same time a valid research instrument and a practical tool for enhancing the quality of students’ learning. In addition, the four studies emphasise that in order to enhance teaching and learning in higher education, various perspectives have to be taken into account. This study sheds light on the interaction between students’ approaches to learning, their conceptions of good teaching, their experiences of the teaching-learning environment, and finally, the disciplinary culture.

U.S. Asylum Policy and the New World Order

"In the new world order, differences in political ideology have given way to differences in economic conditions between nation states as the prompting force for the outflow of would-be refugees and asylum seekers. In part, these pressures are associated with the political disintegration of the poorer republics of the former Soviet Union and its former satellite nations into ethnic enclaves. But the most endemic of the new contributory pressures are emanating from North-South economic differences between the "have" and "have-not" nations."

Design and Simulation of a Solar Powered UAV for Remote Sensing Tasks Technical Report

This research deals with the development of a Solar-Powered UAV designed for remote sensing, in particular to the development of the autopilot sub-system and path planning. The design of the Solar-Powered UAS followed a systems engineering methodology, by first defining system architecture, and selecting each subsystem. Validation tests and integration of autopilot is performed, in order to evaluate the performances of each subsystem and to obtain a global operational system for data collection missions. The flight tests planning and simulation results are also explored in order to verify the mission capabilities using an autopilot on a UAS. The important aspect of this research is to develop a Solar-Powered UAS for the purpose of data collection and video monitoring, especially data and images from the ground; transmit to the GS (Ground Station), segment the collected data, and afterwards analyze it with a Matlab code.

Mathematical modelling of the impaction and spreading of spray droplets on leaves

This thesis concerns the development of mathematical models to describe the interactions that occur between spray droplets and leaves. Models are presented that not only provide a contribution to mathematical knowledge in the field of fluid dynamics, but are also of utility within the agrichemical industry. The thesis is presented in two parts. First, thin film models are implemented with efficient numerical schemes in order to simulate droplets on virtual leaf surfaces. Then the interception event is considered, whereby energy balance techniques are employed to instantaneously predict whether an impacting droplet will bounce, splash, or adhere to a leaf.

Design of high-order filters with restricted component values

The feasibility of realising a high-order LC filter with a small set of different capacitor values, without sacrificing the frequency response specifications, is indicated. This idea could be conveniently adopted in other filter structures also—for example the FDNR transformed filter realisations.

Prevalence, persistence and control of Salmonella and Listeria in shrimp and shrimp products: A review.

Shrimp are an important commodity in the international fisheries trade and there is an indication of an increase in worldwide consumption of this crustacean. Salmonella and Listeria have been isolated from shrimps and shrimp products on a regular basis since the 1980s. The continued reporting of the presence of these pathogens in fresh and frozen shrimps, and even in the lightly preserved and ready-to-eat products, indicates that the existing practices used by the manufacturers or processors are insufficient to eliminate these pathogens. This paper reviews the information available on Salmonella and Listeria in shrimp and makes recommendations on control options and avenues for future research in order to improve shrimp safety and quality.

Structure and dynamics of two-dimensional sheared granular flows

The structure and dynamics of the two-dimensional linear shear flow of inelastic disks at high area fractions are analyzed. The event-driven simulation technique is used in the hard-particle limit, where the particles interact through instantaneous collisions. The structure (relative arrangement of particles) is analyzed using the bond-orientational order parameter. It is found that the shear flow reduces the order in the system, and the order parameter in a shear flow is lower than that in a collection of elastic hard disks at equilibrium. The distribution of relative velocities between colliding particles is analyzed. The relative velocity distribution undergoes a transition from a Gaussian distribution for nearly elastic particles, to an exponential distribution at low coefficients of restitution. However, the single-particle distribution function is close to a Gaussian in the dense limit, indicating that correlations between colliding particles have a strong influence on the relative velocity distribution. This results in a much lower dissipation rate than that predicted using the molecular chaos assumption, where the velocities of colliding particles are considered to be uncorrelated.

Lost in space: The place of the architectural milieu in the aetiology and treatment of schizophrenia

Purpose – Psychological and epidemiological literature suggests that the built environment plays both causal and therapeutic roles in schizophrenia, but what are the implications for designers? The purpose of this paper is to focus on the role the built environment plays in psycho‐environmental dynamics, in order that negative effects can be avoided and beneficial effects emphasised in architectural design. Design/methodology/approach – The approach taken is a translational exploration of the dynamics between the built environment and psychotic illness, using primary research from disciplines as diverse as epidemiology, neurology and psychology. Findings – The built environment is conceived as being both an agonist and as an antagonist for the underlying processes that present as psychosis. The built environment is implicated through several means, through the opportunities it provides. These may be physical, narrative, emotional, hedonic or personal. Some opportunities may be negative, and others positive. The built environment is also an important source of unexpected aesthetic stimulation, yet in psychotic illnesses, aesthetic sensibilities characteristically suffer from deterioration. Research limitations/implications – The findings presented are based on research that is largely translated from very different fields of enquiry. Whilst findings are cogent and logical, much of the support is correlational rather than empirical. Social implications – The WHO claims that schizophrenia destroys 24 million lives worldwide, with an exponential effect on human and financial capital. Because evidence implicates the built environment, architectural and urban designers may have a role to play in reducing the human costs wrought by the illness. Originality/value – Never before has architecture been so explicitly implicated as a cause of mental illness. This paper was presented to the Symposium of Mental Health Facility Design, and is essential reading for anyone involved in designing for improved mental health.

Collation, analysis and research of thermal benefits of green life in the urban landscapes

This project reviewed international research conducted on the possible role of plants in alleviating high temperatures in our living spaces. The literature review served to identify the work that has already been carried out in the area and to highlight the gaps to be filled by experimental research. A pilot study then investigated the thermal properties of six of the most common landscaping materials. This project clearly shows that plants can play a significant role in modifying the thermal conditions of urban environments. Tall trees can shade nearby buildings and allow for reductions in cooling costs. In addition to basic shading, the dispersal of heat via the plant’s natural transpiration stream has long been recognised as an important component of the urban energy balance. It has been shown that urban temperatures can be up to 7°C higher than nearby rural areas, illustrating the impact of plants on their environment. These benefits argue against the idea of removing plants from landscapes in order to save on water in times of drought. Similarly, the idea of switching to artificial turf is questionable, since artificial turf still requires watering and can reach temperatures that far exceed the safe range for players. While vegetation offers evaporative cooling, non-vegetative, impervious surfaces such as concrete do not, and can therefore cause greater surface and soil temperatures. In addition, the higher temperatures associated with these impervious surfaces can negatively affect the growth of plants in surrounding areas. Permeable surfaces, such as mulches, have better insulating properties and can prevent excessive heating of the soil. However, they can also lead to an increase in reflected longwave radiation, causing the leaves of plants to close their water-conducting pores and reducing the beneficial cooling effects of transpiration. The results show that the energy balance of our surroundings is complicated and that all components of a landscape will have an impact on thermal conditions.

Expression and function of angiotensins in the regulation of intraocular pressure - an experimental study

Glaucoma is a multifactorial long-term ocular neuropathy associated with progressive loss of the visual field, retinal nerve fiber structural abnormalities and optic disc changes. Like arterial hypertension it is usually a symptomless disease, but if left untreated leads to visual disability and eventual blindness. All therapies currently used aim to lower intraocular pressure (IOP) in order to minimize cell death. Drugs with new mechanisms of action could protect glaucomatous eyes against blindness. Renin-angiotensin system (RAS) is known to regulate systemic blood pressure and compounds acting on it are in wide clinical use in the treatment of hypertension and heart failure but not yet in ophthalmological use. There are only few previous studies concerning intraocular RAS, though evidence is accumulating that drugs antagonizing RAS can also lower IOP, the only treatable risk factor in glaucoma. The main aim of this experimental study was to clarify the expression of the renin-angiotensin system in the eye tissues and to test its potential oculohypotensive effects and mechanisms. In addition, the possible relationship between the development of hypertension and IOP was evaluated in animal models. In conclusion, a novel angiotensin receptor type (Mas), as well as ACE2 enzyme- producing agonists for Mas, were described for the first time in the eye structures participating in the regulation of IOP. In addition, a Mas receptor agonist significantly reduced even normal IOP. The effect was abolished by a specific receptor antagonist. Intraocular, local RAS would thus to be involved in the regulation of IOP, probably even more in pathological conditions such as glaucoma though there was no unambiguous relationship between arterial and ocular hypertension. The findings suggest the potential as antiglaucomatous drugs of agents which increase ACE2 activity and the formation of angiotensin (1-7), or activate Mas receptors.

Electron-Energy Loss Spectroscopy (Eels) Of Organic-Molecules In Vapor-Phase - Design And Fabrication Of An Indigenous Eel Spectrometer

An indigenous electron energy loss spectrometer has been designed and fabricated for the study of free molecules. The spectrometer enables the recording of low-resolution electronic spectra of molecules inthe vapour phase with ready access to the vacuum ultraviolet region. Electron energy loss spectra of aliphatic alcohols and carbonyl compounds as wellas of benzene derivatives have been recorded with the indigenous spectrometer and the electronic transitions in these molecules discussed.