Seasonal differences in the effect of isolation and restraint stress on the luteinizing hormone response to gonadotropin-releasing hormone in hypothalamopituitary disconnected, gonadectomized rams and ewes

Stress responses are thought to act within the hypothalamopituitary unit to impair the reproductive system, and the sites of action may differ between sexes. The effect of isolation and restraint stress on pituitary responsiveness to GnRH in sheep was investigated, with emphasis on possible sex differences. Experiments were conducted during the breeding season and the nonbreeding season. In both experiments, 125 ng of GnRH was injected i.v. every 2 h into hypothalamopituitary disconnected, gonadectomized rams and ewes on 3 experimental days, with each day divided into two periods. During the second period on Day 2, isolation and restraint stress was imposed for 5.5 h. Plasma concentrations of LH and cortisol were measured in samples of blood collected from the jugular vein. In the second experiment (nonbreeding season), plasma concentrations of epinephrine, norepinephrine, 3,4-dihydroxyphenylalanine, and 3,4-dihydroxyphenylglycol were also measured. In both experiments, there was no effect of isolation and restraint stress on plasma concentrations of cortisol in either sex. During the breeding season, there was no effect of isolation and restraint stress on plasma concentrations of LH in either sex. During the nonbreeding season, the amplitude of the first LH pulse after the commencement of stress was significantly reduced (P < 0.05) in rams and ewes. In the second experiment, during stress there was a significant increase (P < 0.05) in plasma concentrations of epinephrine in rams and ewes and significantly higher (P < 0.05) basal concentrations of norepinephrine in ewes than in rams. These results suggest that in sheep stress reduces responsiveness of the pituitary gland to exogenous GnRH during the nonbreeding season but not during the breeding season, possibly because of mediators of the stress response other than those of the hypothalamus-pituitary-adrenal gland axis.

The response of ground and bark foraging insectivorous birds across an urban–forest gradient

This paper assesses the response of four common species of forest dependant insectivorous birds to an urban–forest gradient. The presence or absence was recorded for each species in landscapes that varied in landscape and site level attributes. Landscapes were classified into three categories based on their level of urbanisation. Broad comparisons across the landscapes were used to determine species specific response to increasing levels of urbanisation. Site level attributes were modelled to predict the patch occupancy for each species in each of the landscape types. Two broad trends were identified: the superb fairy wren (Malurus cyaneus) and white-browed scrubwren (Sericornis frontalis) displayed a tolerance to urbanisation and the eastern yellowrobin (Eosaltrica australis) and white throated treecreeper (Cormobates leucophaeus) demonstrated a threshold response to urbanisation. The density of roads (&minus;ve) and the extent of tree cover (+ve) in a landscape were highly correlated with the occurrence of urban sensitive species while at the site level the density of roads and density of rivers were the strongest contributors to their presence. The marked differences in the isolation and connectivity of patches where the threshold for urban sensitive species ceases are the likely contributors to their decline and sensitivity to suburban habitats. Conservation and management of urban sensitive species is largely dependant on the way urban development is managed. Of critical importance is careful planning in urban-fringe environments.

Spectral sensitivity of cone photoreceptors and opsin expression in two colour-divergent lineages of the lizard Ctenophorus decresii

Intraspecific differences in sensory perception are rarely reported but may occur when a species range extends across varying sensory environments, or there is coevolution between the sensory system and a varying signal. Examples in colour vision and colour signals are rare in terrestrial systems. The tawny dragon lizard Ctenophorus decresii is a promising candidate for such intraspecific variation, because the species comprises two geographically and genetically distinct lineages in which throat colour (a social signal used in intra- and inter-specific interactions) is locally adapted to the habitat and differs between lineages. Male lizards from the southern lineage have UV-blue throats, whereas males from the northern lineage are polymorphic with four discrete throat colours that all show minimal UV reflectance. Here, we determine the cone photoreceptor spectral sensitivities and opsin expression of the two lineages, to test whether they differ, particularly in the UV wavelengths. Using microspectrophotometry on retinal cone photoreceptors, we identified a long-wavelength-sensitive (LWS) visual pigment, a 'short' and 'long' medium-wavelength-sensitive (MWS) pigment and a short-wavelength-sensitive (SWS) pigment, all of which did not differ in λmax between lineages. Through transcriptome analysis of opsin genes we found that both lineages express four cone opsin genes, including the SWS1 opsin with peak sensitivity in the UV range, and that amino acid sequences did not differ between lineages with the exception of a single leucine to valine substitution in the RH2 opsin. Counts of yellow and transparent oil droplets associated with LWS+MWS and SWS+UVS cones, respectively, showed no difference in relative cone proportions between lineages. Therefore, contrary to predictions, we find no evidence of differences between lineages in single cone photoreceptor spectral sensitivity or opsin expression. However, we confirm the presence of four single cone classes, suggesting tetrachromacy in C. decresii, and we also provide the first evidence of UV sensitivity in agamid lizards.

Beyond mimesis : place, interpretation and response

My study examines the subjective nature of artistic interpretation through the notion of mimesis as process or transformation of material. Influential factors that mediate in the artistic process, such as memory, reflection and an awareness of cultural analogy and metaphor, are examined and related to a specific project in the studio, where the mediation process is further influenced by the materials used to produce the images. My studies of the concept of mimesis have revealed an intermediary realm that exists in the space between empirical reality and its interpretation. Throughout history the process of mimesis has been integral to all forms of the arts. In Plato's time the production of an image that simulated things as they appeared to the eye was considered a desired ideal. Aristotle later introduced developments which extended this concept to include a refiguring or reforming of material derived from the original source, making new connections between existing factors and in this transformation bringing new meanings to a symbolically constituted world. This discussion of the representation of reality, the influence of a dialogue between notions of imitation and the recreation of material continues throughout the exegesis. My study emphasises the interpretive stage of the mimetic process where a consideration of these themes is most relevant and some of the factors that can influence its outcome. It is my opinion that the production of images in response to the particularities of place can be defined in three stages. Firstly, the experience of the place; secondly, the beginning and maturation of the idea or concept; where mimesis takes place, and thirdly, the production of the art work in response. This process is illustrated in Part 2 of the exegesis, where the development of the studio work is documented and linked with the themes discussed in Part 1. The geographic site or place I selected to study is adjacent to Mt. Noorat, a volcanic site in the Western district of Victoria; the surrounding plains are littered with scoria that has been thrown out of the volcano thousands of years ago. Early British, Scottish and Irish settlers to this region used the stone to construct fences reminiscent of their homeland, through this activity they cleared the land and confined and protected their stock. My interests are in factors that include - the material of the stone, notions of enclosure and safety, of boundaries and circumscribed space, and of the cultural reflection that has taken place in this reconstruction of Eurocentric vision. These walls also represent the means by which land was enclosed and property defined, moving from a situation of public access to notions of ownership and the annexation of land for individual gain. Around each point of eruption, the craggy volcanic scoria has been used to create a constructed landscape which both symbolises and mirrors the Anglo - Celtic origins of the people. I have used the legend of Narcissus to illustrate the self-reflective and introspective processes that the settlers invoked in their attempts to come to terms with a strange land. I consider that the story of Narcissus, who fell in love with his own reflection, finds a parellel in the creation of the walls. The re-creation of artifacts from their own cultural environment provided the settlers with a familiar 'face' in an alien world; a reassurance of the familiar in an unfamiliar terrain. Part of this study is an investigation of this notion of landscape as cultural reflection. Geographers have long known that landscape is a cultural construct, an historically evolving ideal manifested in painting, prints and drawings as well as poetry, gardens and parks. One can view these constructions as illustrations or images of meaning which constitute representations of cultural ideals. The neo-classical influence reflected in the paintings of artists who accompanied the early expeditions to Australia demonstrates these themes. The medium of the mirror provides the opportunity to suggest aspects of a cultural reflection and an awareness of identity that has relevance to contemporary Australian culture, therefore, I have allowed it to play a major role throughout this study. Its role in mimesis, firstly, as a reflection in an imitative sense is established, then in its refigurative role, in which the similarities between the original and the reformed rely more on correlative factors than representation. I have used examples from the history of art to illustrate this potential. The formation and development of a narrative involving reflection threads throughout the thesis, both in the visual presentation and in the exegesis. The production of a body of paintings, drawings and sculpture reflect my interpretation and response to the particular site. The correspondences between these works and my theoretical concerns is articulated in the exegesis. The metaphor implied by the use of the walls as agents of enclosure also refers to the capacity of the individual to be confined by notional boundaries and restrictive practices where totalising systems of thought dominate theoretical debate and restrict its freedom. I have used images where gaps in the walls represent the potential implicit to the concept of liminal space, where the spectator moves from one physical space to another and from one stage of development to another. The threshold of this opening in the walls becomes the site where transformation can take place, a metaphor for the mimetic process where the initial experience is translated and transformed into the final product. The paintings, drawings and other works in this series fulfil the role of marks on the surface of the mirror, separating the initial experience from the processes of memory, reflection and speculation. The works draw attention to the materiality that they represent and yet provide the opportunity for new insights and experiences, allowing the subjective nature of artistic activity to combine symbolic elements relating to the site, resulting in the production of meaning.

Isolation and characterisation of Arabidopsis RAD30 and ERCC1

This thesis describes the isolation and characterisation of two plant genes, AtERCC1 and AtRAD30. Evidence from protein homology comparisons, and functional complementation, in vitro mutagenesis, or interaction assays suggests the involvement of these genes in the repair or tolerance, respectively, of UV-induced DNA change.

Testosterone manipulation post-castration does not alter cloacal gland growth differences in male quail selected for divergent plasma corticosterone stress response

Japanese quail selected for reduced (low-stress, LS) rather than exaggerated (high-stress, HS) plasma corticosterone response to brief restraint have consistently shown greater cloacal gland (CG) development, an androgen-dependent trait. In this study, the effects of testosterone implants on levels of plasma testosterone and CG development in castrated LS and HS quail were determined. Stress-line males were castrated and randomly allocated to 1 of 3 testosterone treatments: the empty testosterone (ET), low testosterone (LT), or high testosterone (HT) implant group. Cloacal gland volume was determined at 4 weekly intervals that represented ranges of 1 to 9 d, 8 to 17 d, 15 to 24 d, and 22 to 31 d after castration and testosterone implantation. Levels of plasma testosterone were also assessed at the end of the study. Development of the CG was affected by quail line (LS > HS), testosterone treatment (HT > LT > ET), and time of measurement (1 to 9 d < 8 to 17 d < 15 to 24 d = 22 to 31 d after castration and testosterone implantation). A significant interaction between testosterone treatment and time of measurement on CG volume was also detected (with CG volume generally increasing with time in LT- and HT-treated quail, but not in ET-treated quail). However, even though HT implant treatments induced higher CG development than did LT treatments beyond the first interval of CG volume measurement, and despite the finding of greater CG volumes in LS than HS quail during the last 2 measurement intervals within each of the LT and HT groups, no interaction was observed between testosterone implant dosages and quail stress line on CG volume. Thus, by the end of the study, regardless of testosterone dose, CG volume was consistently greater in LS quail than in their HS counterparts. In addition, although, as expected, the testosterone implant treatment significantly altered levels of plasma testosterone (HT > LT > ET), neither quail line nor its interaction with testosterone treatment affected plasma testosterone. The present findings suggest that the often-observed depressed CG development in the HS line may be independent of testosterone effects

Building the client's relational base

Developed from nearly 20 years' practice and consulting experience, this ground-breaking text challenges practitioners to understand, and work, with their clients as relational beings rather than independent units, whatever the presenting problem might be. The book focuses on an often neglected key condition, that sustainable and accountable personal relationships are a precondition for health and well-being, and argues that there are always opportunities to deepen the quality, and range, of the client's connections with their current and future significant-others.The central concern of the book is to describe practical actions that can be taken by any professional committed to strengthening the relational base of their clients - an agenda that is supported by coherently woven insights from critical theory and social epidemiology. Written in a compelling style and brought to life with more than twenty case vignettes, this original, practical and rich resource offers practitioners usable resources that can be incorporated within many practice roles.Especially relevant to senior students and those in casework, this innovative, timely, multidisciplinary material is ideal for all those who wish to make a practical difference to the lives of their clients.

Space-for-time substitution to assess likely response of aquatic ecosystems to future climate-related change

Predicting and managing ecological response to a changing climate is often limited by an incomplete understanding of response thresholds and biogeographic differences. For example, step changes in rainfall and runoff, and threshold dynamics and hysteresis in ecological response make projection of future conditions difficult. To combat these constraints we propose that biophysical data across exiting climatic gradients can be used in a space-for-time substitution to predict climate-related ecological response elsewhere. This method builds on previous attempts at space-for-time substitution by using patterns in physical and physicochemical data to explain biological differences across the spatial gradient, then using those patterns to formulate hypotheses of temporal ecological response and finally testing those hypotheses on temporal data available in a second, similar region of interest. 

Response to long-distance relocation in Asian elephants (Elephas maximus) : monitoring adrenocortical activity via serum, urine, and feces

Understanding how elephants respond to potentially stressful events, such as relocation, is important for making informed management decisions. This study followed the relocation of eight Asian elephants from the Cocos (Keeling) Islands to mainland Australia. The first goal of this study was to examine patterns of adrenocortical activity as reflected in three different substrates: serum, urine, and feces. We found that the three substrates yielded very different signals of adrenocortical activity. Fecal glucocorticoid metabolites (FGM) increased as predicted post-transport, but urinary glucocorticoid metabolites (UGM) were actually lower following transport. Serum cortisol levels did not change significantly. We suggest that the differences in FGM and UGM may reflect changes in steroid biosynthesis, resulting in different primary glucocorticoids being produced at different stages of the stress response. Additional studies are needed to more thoroughly understand the signals of adrenocortical activity yielded by different substrates. The second goal was to examine individual variation in patterns of adrenal response. There was a positive correlation between baseline FGM value and duration of post-transfer increase in FGM concentration. Furthermore, an individual's adrenocortical response to relocation was correlated with behavioral traits of elephants. Elephants that were described by keepers as being “curious” exhibited a more prolonged increase in FGM post-transfer, and “reclusive” elephants had a greater increase in FGM values. Future research should investigate the importance of these personality types for the management and welfare of elephants.

Expert in my pocket: creating first person POV videos to enhance mobile learning

Worldwide, there has been a rapid increase in both the use of mobile technologies as a conduit for student learning and the use of wearable cameras to record sporting and recreational activities. The Expert in My Pocket project (EiMP) has combined these two technologies to produce a repository of freely available short videos and supporting materials to enhance student development of psychomotor clinical skills. The videos are presented from a first person point of view (1PPOV) with expert health professionals ‘thinking aloud’ as they demonstrate selected skills. Research indicates that students and educators overwhelmingly support the concept of EiMP videos and more importantly value the 1PPOV as an authentic view. This paper demonstrates the techniques and equipment employed to produce these videos, which consisted of a chest or head mounted GoPro camera operated via an iPad. Additionally, the paper explains another innovative feature, Quick Response (QR) Codes, that when linked to the videos placed on equipment assists with “just in time” mobile learning.