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Guy Kendall White graduated from the University of Sydney, obtaining a BSc (Hons) (1st class) in 1945 and an MSc in 1947. He attended the University of Oxford and obtained a DPhil, studying low-temperature physics in the Clarendon Laboratory. He had a productive research career as a condensed matter experimental physicist, focusing on transport and thermophysical properties of solids at low temperatures. He had an extensive network of international collaborators and, in 1959, authored Experimental Techniques in Low-Temperature Physics, which came to be regarded as an essential handbook for those doing low-temperature physics. He was a world leader in the field of thermal expansion in solids at low temperatures. He produced important compilations of thermophysical data that are of great value to technologists, scientists and engineers. He was influential in the development of the discipline of solid state physics in Australia, and his mentoring launched the careers of many young scientists.

Aquatic pollution events can be detrimental to the survival of wildlife, particularly birds. To decontaminate affected birds, large quantities of fresh water are required. A recent study using seabird feathers, demonstrated that seawater wash/rinse can effectively remove oil from feathers. However to determine whether seawater was effective for live birds, we used 36 mallard ducks to replicate the oiled feather wash/rinse study. We investigated the time and volume of water used, bird water-proofing scores after daily swims and a barbule amalgamation index (BAI), for feathers collected at stages throughout the process. Results indicate that for oiled mallard ducks, the use of seawater for decontamination wash/rinse was effective. Seawater wash however, took longer and used a greater quantity of water. Time to birds being waterproof, was not significantly different between groups. The use of seawater has worldwide application for oiled wildlife response activities particularly in areas where freshwater supplies are limited.

Measurements are made of the stress developed in near-spherical elastic inclusions in an elastic plastic matrix under both tension and compression loading. Two experimental conditions are reported. The first case is where no thermal mismatch exists between the inclusions and the matrix, so that the stress in the inclusion is purely a result of the misfit in the elastic moduli and of the distortion of the plastic slip-line field around the inclusion. The observations are believed to be the first such and are in qualitative agreement with finite-element modelling for idealised inclusion distributions. The second case is the more usual one where a thermal misfit stress exists and observations are reported of the stress relief effects caused by the interaction of the plasticity-induced stress with the thermal and elastic misfit stresses.

The elastic and physical properties of a tungsten-copper (W-Cu) bi-continuous composite were predicted from microstructural data captured using TriBeam serial sectioning. The reconstructed 3D volume was converted into a Finite Element (FE) mesh. The minimum representative volume elements (RVEs) required for calculating phase volume fraction, Young's modulus and Poisson’s ratio were determined. The predicted volume fraction of Cu and Young's modulus were found to be within 2.6%, and 3.6% of the respective experimentally determined values. The minimum RVE size is found to be dependent on the material property. The variability in the required RVE size must be considered for material properties of W-Cu and similar bi-continuous composite microstructures.

Background In order to make informed decisions about how best to support children and young people with disabilities, effective strategies that facilitate active and meaningful participation in school are required. Clinical factors, diagnosis or impairments somewhat helpful in determining what should be provided in interventions. However, clinical factors alone will not offer a clear view of how to support participation. It is helpful then to look at wider psychosocial and environmental factors. The aim of this review was to synthesise evidence of psychosocial and environmental factors associated with school participation of 4-12 year old children with disabilities to inform the development of participation-fostering interventions.Methods A systematic search and synthesis using realist methods was conducted of published research. Papers had to include consideration of psychosocial and/or environment factors for school participation of children with disabilities. The review was completed in accordance with the Realist and Meta-narrative Evidence Syntheses: Evolving Standards (RAMESES) and Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Papers were identified via Boolean search of the electronic databases MEDLINE, CINAHL, PhycINFO and ERIC (January 2006-October 2018). Appraisal focussed on contributions in terms of whether the articles are appropriate for the review (relevance) and research quality (rigour). Data were analyzed using content and thematic analysis methods using a realist framework. A narrative synthesis of results was reported.Results and implicationsWe identified 1828 papers in the initial search. Seventy two papers were included in the final synthesis. Synthesis of findings led to three overarching mechanisms representing psychosocial factors for children (1) identity (2) competence and (3) experience of mind and body. Environmental aspects (context) compromised five interrelated areas: (1) structures and organization, (2) peers, (3) adults, (4) space and (5) objects. Our synthesis provides insights on how professionals may organize efforts to improve children’s participation. Consideration of these findings will help to proactively deal with suboptimal participation outcomes. Development of theoretically determined assessments and interventions for management of school participation are now required.

The martensitic transformation in indium-thallium alloys is reviewed with a focus on the nature of the transformation as has been investigated using elastic and lattice vibrational properties. Recent measurements from thermal-neutron Laue and cold-neutron, triple-axis experiments are presented in an attempt to ratify the traditional explanation for the transformation as being driven by phonon softening for low-ζ \( \left[ {\upzeta \upzeta 0} \right]\left[ {{\upzeta{{ \bar{\upzeta }}}}0} \right] \) (i.e., T1) phonons. No evidence for phonon softening has been found to as low as ζ = 0.02 reciprocal lattice units on the T1 phonon branch. An alternative mechanism is advanced, for the transformation involving nucleation and growth on {111} planes, which appears to be consistent with electron diffuse scattering in the system. Such a mechanism is also consistent with the transition being driven by the electronic free energy of the system, as has been demonstrated by other properties.

Background - There are few large scale studies about the nature and extent of the actual use of standardised assessments for Autism Spectrum Disorder diagnosis in clinical practice. This study compares and contrasts practice in diagnostic services for both adults and children.\ud \ud Method - We conducted an analysis of retrospective case notes from 150 cases (70 adult, 80 children) assessed for Autism Spectrum Disorder by 16 diagnostic services.\ud \ud Results - We found differences between adult and child services in staff training and use of standardised assessment during diagnosis. All child services had staff trained in and regularly using standardised assessments. Most adult services had staff trained in using instruments but only half used them regularly. Administration of standardised ASD assessments was ten times more likely in children than in adults (OR = 10.1; CI = 4.24, 24.0). Child services selected the ADOS as the standardised tool and adult services selected the DISCO, with very little overlap. Decisions to administer standardised tools were not based on case complexity but rather the same process was applied to all referrals within a service. The three recommended components of assessment (clinical history, clinical observation and contextual information) were included for the majority of cases, although clinical observation was more frequently used with children than with adults.\ud \ud Conclusions - Based on the findings, we suggest a need for a wider range of appropriate assessments for use with adults, particularly those with an intellectual disability and for further research into the reasons behind the choices clinicians make during the assessment process. For child services in Scotland, there is a need for more training in use of current diagnostic interviews. Clinicians did not vary tools used based on complexity, suggesting that this is a notion still to be clearly defined and operationalised in clinical decision making about the use of standardised assessments.

Disfluency is a characteristic feature of spontaneous human speech, commonly seen as a consequence of problems with production. However, the question remains open as to why speakers are disfluent: Is it a mechanical by-product of planning difficulty, or do speakers use disfluency in dialogue to manage listeners' expectations? To address this question, we present two experiments investigating the production of disfluency in monologue and dialogue situations. Dialogue affected the linguistic choices made by participants, who aligned on referring expressions by choosing less frequent names for ambiguous images where those names had previously been mentioned. However, participants were no more disfluent in dialogue than in monologue situations, and the distribution of types of disfluency used remained constant. Our evidence rules out at least a straightforward interpretation of the view that disfluencies are an intentional signal in dialogue.

Two new indole spermidine alkaloids, didemnidines A (1) and B (2), have been isolated from the New Zealand ascidian Didemnum sp. The structures of the metabolites, determined by analysis of 2D NMR spectra and confirmed via synthesis, embody an indole-3-glyoxylamide moiety linked to the N(1) position of spermidine, the latter motif being particularly rare among marine natural products. Didemnidine B and a synthetic precursor exhibited mild in vitro growth inhibition of Plasmodium falciparum with IC(50)'s of 15 and 8.4 μM, respectively.

Homologues of all components of the Saccharomyces cerevisiae FEAR and MEN pathways are expressed in the multinucleated hyphae of Ashbya gossypii despite the lack of controlled nuclear positioning and mitosis-dependent septum formation. In this system, MEN loses its dominant role, and nuclear divisions are controlled by FEAR homologues., In Saccharomyces cerevisiae, mitosis is coupled to cell division by the action of the Cdc fourteen early anaphase release (FEAR) and mitotic exit network (MEN) regulatory networks, which mediate exit from mitosis by activation of the phosphatase Cdc14. The closely related filamentous ascomycete Ashbya gossypii provides a unique cellular setting to study the evolution of these networks. Within its multinucleate hyphae, nuclei are free to divide without the spatial and temporal constraints described for budding yeast. To investigate how this highly conserved system has adapted to these circumstances, we constructed a series of mutants lacking homologues of core components of MEN and FEAR and monitored phenomena such as progression through mitosis and Cdc14 activation. MEN homologues in A. gossypii were shown to have diverged from their anticipated role in Cdc14 release and exit from mitosis. We observed defects in septation, as well as a partial metaphase arrest, in Agtem1Δ, Agcdc15Δ, Agdbf2/dbf20Δ, and Agmob1Δ. A. gossypii homologues of the FEAR network, on the other hand, have a conserved and more pronounced role in regulation of the M/G1 transition. Agcdc55Δ mutants are unable to sequester AgCdc14 throughout interphase. We propose a reduced model of the networks described in yeast, with a low degree of functional redundancy, convenient for further investigations into these networks.

The thermal expansion of a synthetic single-crystal sample of magnetite (Fe3O4) in the [111] direction has been investigated for the temperature range of 4.2–300 K using three-terminal capacitance dilatometry. The strain results and corresponding thermal expansion curve show the Verwey transition to be first-order with T v = 120 ± 2 K. At T = 4.2–70 K, the sample shows Invar-like behaviour.

The greater bilby Macrotis lagotis once occupied about 70% of the Australian mainland but is now restricted in occurrence to just 20% of its former range. It is classified as Extinct in New South Wales. We assessed the major components of the diet of a recently re-introduced population of bilbies at Scotia Sanctuary, in western New South Wales, from faecal material collected over a period of 13 months. Animals consumed more invertebrates than green plant material and seeds throughout the study, although there was temporal variation in the presence of these food categories. Five orders of invertebrates were identified, with Coleoptera (beetles) occurring in more than 80% of faecal samples and Isoptera (termites) and Formicidae (ants) in 48% and 40%, respectively. These results identify key components of the diet of the first population of bilbies in New South Wales since the early 20th century and, combined with detailed studies of habitat requirements and prey abundance, should assist with selection of ad...

Welding residual stresses have an effect on many aspects of the integrity of structures but are normally one of the largest unknown stresses. Residual stresses are difficult to measure and to estimate theoretically but are often significant when compared with the service stresses on which they superimpose. High tensile residual stresses can lead to loss of performance in corrosion, fatigue and fracture. In this research, measurement of residual stresses by the neutron diffraction technique is compared to an analysis of a sample geometry by theoretical finite-element procedures. The results indicate good qualitative agreement. One of the key issues in this comparison relates to what is termed “gauge volume” in the measurement technologies and what might be described as a “calculation volume” in theoretical approaches.

Knowledge of the habitat requirements of threatened species at both local and landscape scales is crucial for maintaining viable populations and for making conservation and management decisions. Here, we use live trapping and radio-tracking to investigate habitat use by four species of threatened marsupials – burrowing bettongs ( Bettongia lesueur ), brush-tailed bettongs ( B. penicillata ), greater bilbies ( Macrotis lagotis ), and bridled nailtail wallabies ( Onychogalea fraenata ). The study populations had been re-introduced to Scotia Sanctuary in western New South Wales, Australia, within a predator-proof area. All showed preferences for particular macrohabitats while resting by day, with M . lagotis and B . penicillata selecting Eucalyptus woodland with Triodia understorey and B . lesueur and O . fraenata selecting Eucalyptus woodland with shrubs. However, they showed no such partiality at night. Bettongia penicillata used areas with Triodia and litter but few herbs for shelter, while burrows of M. lagotis avoided shrubs. Habitat components that influenced trap captures were: crust cover and herb layer cover (negative) for B . penicillata , trees B . lesueur, crust cover for M . lagotis , and crust cover and trees O. fraenata (both negative). There was also a negative association at this scale between B. penicillata and both B. lesueur and M. lagotis , suggesting the possibility of competition. Our results support the idea that studies at multiple spatial scales are crucial to understand the habitat use and requirements of threatened fauna, and should therefore be incorporated into future re-introduction programs.

The southern hairy-nosed wombat ( Lasiorhinus latifrons ) is a seasonal breeding, burrowing marsupial adapted to a semi-arid environment and the closest relative of the endangered northern hairy-nosed wombat ( Lasiorhinus krefftii ). Females typically give birth to one to two young every 3 years with young weaned at 360–400 days. This study examined the occurrence of polyoestry in a wild population of southern hairy-nosed wombats, and in particular the ability of this species to produce additional offspring in the same breeding season if a young was prematurely lost or removed. Pouch young were removed during the breeding seasons of 1996/1997 and 2003. No females from the 1996 ( n =3)/1997 ( n =3) group gave birth to a second pouch young in the same breeding season. However, two females in this group gave birth to young the following season. In contrast, all the 2003 group of females ( n =6) produced a second offspring in the same breeding season after removal of pouch young (RPY). The reason for the different response to RPY between the two groups is unknown. These studies confirm that southern hairy-nosed wombats are polyoestrus in the wild and are capable of producing more than one offspring in a single breeding season. Females that failed to return to oestrus in the breeding season that pouch young were removed bred again in the following season. Rapid replacement of southern hairy-nosed wombat pouch young in the same breeding season as RPY suggests that this procedure, linked to either hand-rearing or interspecific cross-fostering, should be seriously considered as a priority conservation action to increase the population size of the critically endangered sister species, the northern hairy-nosed wombat.

This study investigates the effect of three exogenous gonadotrophin regimens on ovarian follicular development in southern hairy-nosed wombats during the non-breeding season. Females were given either porcine follicle stimulating hormone (pFSH; total of 200 mg at 12 h intervals over 7 (Group 1), or 4 days (Group 2)), or pregnant mares' serum gonadotrophin (PMSG; single dose of 150 I.U. (Group 3)). In all treatment groups 25 mg of porcine luteinising hormone (pLH) was used to trigger maturation; Groups 1 and 2 received pLH 12 h after the final pFSH injection and Group 3 received pLH 72 h after PMSG. The results showed Group 1 produced significantly more follicles per ovary (5.91+/-1.28) than Group 2 (1.67+/-0.62), or Group 3 (2.17+/-1.16) at p0.05. Control females received saline injections concurrently with the three treatment groups (n=6; 2 control animals for each treatment group). No follicular development occurred in any control female. Analysis of oocyte nuclear status revealed that while oocytes from all three treatment groups had resumed meiosis, only those in Group 1 (7-day pFSH/pLH treatment) progressed to metaphase II. These results have implications for the development of assisted breeding strategies in this species.

Welding residual stresses have important consequences for the performance of engineering components and high residual stresses can lead to loss of performance in corrosion, fatigue and fracture. Despite their importance, they are often the single largest unknown in industrial damage situations due to the difficulty of their measurement. In this paper, the neutron diffraction technique is used to investigate residual strains and stresses due to repair welding. The aim of this research was to characterize the residual stress distribution which arises in a welded component as a result of restraint and how it is reduced by subsequent post-weld heat treatment (PWHT). Three-dimensional residual strain/stress distributions are presented. The test results show that restraint during welding increases the levels of residual stress in all three directions. A significant stress relaxation due to PWHT has been observed. Results are also compared with values specified by the structural integrity assessment standard, BS...

This chapter provides an overview of how longitudinal data can be analyzed using mixed effects models. It discusses how mixed effects models benefits L2 researchers, before providing a practical example of how longitudinal mixed effects data analysis can be conducted. The main focus of this chapter employs the lme4 package, which provides an up-to-date implementation of linear mixed effects models. The random effects parameters is needed to model all known sources of random variance amongst the different participants. The summary shows that it includes random intercepts for "student" and "class" and provides information about the variance associated with each. The syntax 1+c_time includes a random intercept, a random slope for c_time and a correlation between the two. This allows for the possibility that there may be a correlation between the random intercepts and random slopes. Random intercepts for subjects and classes were included, as were random slopes for time varying by both students and classes, using maximal random effects structure.

The underlying domain structures of ferroelastic ceramics have a large influence on their macroscopic electromechanical properties. The profile shape functions of certain pseudo-cubic peaks in diffraction patterns collected from these materials can provide a great deal of information about such domain structures. Using both constant-wavelength neutron and high-energy synchrotron x-ray diffraction, profile shape functions of the pseudo-cubic 002 reflection are evaluated in a soft, tetragonal PZT ceramic. Errors in the integrated intensity ratio, important for measuring the degree of domain boundary movement in these materials, are subject to further scrutiny. It is shown that an asymmetric Pearson VII type distribution, integrated numerically between reasonable limits, gives the most accurate value of relative domain populations in these materials. It is also shown that the diffuse scattering caused by ferroelastic domain walls may be used to estimate the amount of material that is affected by microstrains originating at these walls.

Computer-controlled apparatus for the measurements of dynamic Young's modulus and internal friction as functions of temperature, using the piezoelectric ultrasonic composite oscillator technique (PUCOT), has been designed and demonstrated. The versatility of the apparatus and its resonance tracking techniques have been proven by detecting subtle structural phase transformations within the Ca1−xSrxTiO3 perovskite system as well as dramatic changes accompanying the martensitic transformation in a Au–Cd shape-memory alloy. The simplicity of the PUCOT technique allows a system such as this to be constructed easily and with low cost.

The neutron diffraction technique is used to investigate and compare the residual stress characteristics in fully restrained samples with different numbers of beads. The aim of the research was to characterize the residual stress distribution which arises in a welded component with increasing the number of passes or beads. The resolution of the measurements carried out in this work achieves a new level of detail and reveals significant features of the residual stress pattern in multi-bead welding. The findings have important consequences for the design of welding procedures, demonstrating the effects of placing new beads on prior welding.

In this research, both neutron and synchrotron X-ray diffraction techniques have been used to investigate variations in measured d spacing in two reference samples. The reference “stress-free” samples, a set of cubes and a comb sample, were produced using electro-discharge machining (EDM) to obtain a macro-strain-relieved condition. It is shown that there is a variation in microstructure across the parent metal, heat-affected zone (HAZ) and weld metal. A study of the issues in using the cubes and comb sample to provide reference d 0 values for the measurement of residual stress in welding is presented.

The unexpected finding of time-dependent behaviour in athermal martensitic transformations (MT) above the M S temperature has prompted many experimental studies of incubation time. We review here various data scattered in the literature, emphasising the seminal experimental and theoretical work by Kakeshita et al. Contradicting experimental results and alternative concepts as put forward by Otsuka et al. and Planes et al. are discussed in some detail as well. Future experiments to clarify the situation are suggested, in particular the application of X-ray photon correlation spectroscopy to extend the range of observable time scales into regimes dominated by the dynamics of potential embryonic fluctuations.

Welding residual stresses are important in pressure vessel and structural applications. However, residual stress remains the single largest unknown in industrial damage situations. They are difficult to measure or theoretically estimate and are often significant when compared with the in-service stresses on which they superimpose. High residual stresses lead to loss of performance in corrosion, fatigue and fracture. In this research, a measurement of residual stress by the neutron diffraction technique is compared to an analysis of the same geometry by theoretical finite element procedures. The results indicate good agreement but scope for further understanding of the details of modelling the welding heat source, heat transfer and variation of material properties with temperature.

Welding residual stresses have important consequences on the performance of engineering components. High residual stresses may lead to loss of performance in corrosion, fatigue, and fracture but as yet these consequences are poorly quantified. The major cause of this is that residual stress often remains the single largest unknown in industrial damage situations since it is difficult to measure or estimate theoretically. One of the key issues in the study of residual stress is that the detail of the stress distribution on a small scale (in the order of millimeters) can be important. In this paper, the neutron diffraction technique is used which while it is a very expensive technique, is capable of nondestructively measuring residual stresses at this scale up to a depth of 35mm. The investigation reported compares the residual stress characteristics due to various restraints for a single bead and in fully restrained samples with different numbers of beads. This paper considers the results of the neutron diffraction studies in relation to fitness for purpose guidance and implication for pressure vessel design.

The microstructure and magnetic properties of melt-spun Sm(Co 0.88- x Fe x Cu 0.10 Zr 0.02 ) 7.5 ( x = 0.1 and 0.2) alloy ribbons have been studied. The results showed that the as-spun ribbons were in a single phase, SmCo 7 , with the Cu 7 Tb structure. When aged in the temperature range from 720 to 900 °C, the SmCo 7 phase transformed into Sm 2 Co 17 , SmCo 5 , and CoFe(Zr) phases with a minor Sm 2 Co 3 phase. For the x = 0.1 alloy, a large coercivity, H c = 8.7 kOe, was observed although the soft magnetic CoFe(Zr) phase was present in the alloy. The volume fraction of the CoFe(Zr) phase increased when the ageing temperature increased from 720 to 760 °C. At higher ageing temperature, the CoFe(Zr) phase was partially re-dissolved. With an increase in the Fe content in the alloy, the CoFe(Zr) phase increased significantly, causing the coercivity to decrease.

The effects of thyroid dysfunction are thought to be reversible on restoration of euthyroidism, but postmortem and epidemiologic data suggest that subclinical or treated thyroid disease is associated with increased vascular risk. In order to determine the extent of this risk, and to explore whether the nature and/or treatment of thyroid disease are critical in this relationship, we used medical record linkage to match patients with treated thyroid disease of various etiologies with routinely collected national inpatient and daycase hospital discharge records and death records, and assessed the number of hospitalizations from cardiovascular or cerebrovascular disease or death in patients with thyroid disease and control patients. Patients treated for Graves' disease had more hospitalizations from cardiovascular disease than controls (relative risk, 1.42; 95% confidence interval, 1.20 to 1.67; p < 0.001). Toxic multinodular goiter was also associated with significantly higher rates of cardiovascular disease (relative risk, 1.50; 95% confidence interval, 1.11 to 2.02; p = 0.008). Patients with Hashimoto's thyroiditis aged over 50 years had a threefold increase in cardiovascular admissions compared to controls (23.5% and 6.5%, respectively; 95% confidence interval for difference, 6.0% to 27.9%; p = 0.003). Thus, different forms of thyroid disease were associated with increased long-term vascular risk despite restoration of euthyroidism. The mechanisms that mediate this risk are unclear but may not involve thyroid hormone abnormality.

Habitat fragmentation is one of the major contributors to the loss of biodiversity worldwide. However, relatively little is known about its more immediate impacts on within-patch population processes such as social structure and mating systems, whose alteration may play an important role in extinction risk. We investigated the impacts of habitat fragmentation due to the establishment of an exotic softwood plantation on the social kin structure and breeding system of the Australian marsupial carnivore, Antechinus agilis. Restricted dispersal by males in fragmented habitat resulted in elevated relatedness among potential mates in populations in fragments, potentially increasing the risk of inbreeding. Antechinus agilis nests communally in tree hollows; these nests are important points for social contact between males and females in the mating season. In response to elevated relatedness among potential mates in fragmented habitat, A. agilis significantly avoided sharing nests with opposite-sex relatives in large fragment sites (but not in small ones, possibly due to limited nest locations and small population sizes). Because opposite-sex individuals shared nests randomly with respect to relatedness in unfragmented habitat, we interpreted the phenomenon in fragmented habitat as a precursor to inbreeding avoidance via mate choice. Despite evidence that female A. agilis at high inbreeding risk selected relatively unrelated mates, there was no overall increased avoidance of related mates by females in fragmented habitats compared to unfragmented habitats. Simulations indicated that only dispersal, and not nonrandom mating, contributed to inbreeding avoidance in either habitat context. However, habitat fragmentation did influence the mating system in that the degree of multiple paternity was reduced due to the reduction in population sizes and population connectivity. This, in turn, reduced the number of males available to females in the breeding season. This suggests that in addition to the obvious impacts of reduced recruitment, patch recolonization and increased genetic drift, the isolation of populations in habitat patches may cause changes in breeding behaviour that contribute to the negative impacts of habitat fragmentation.

Welding residual stresses have important consequences on the performance of engineering components. High residual stresses lead to loss of performance in corrosion, fatigue and fracture. However, residual stress often remains the single largest unknown in industrial damage situations. They are difficult to measure or theoretically estimate and are often significant when compared with the in-service stresses on which they superimpose. In this paper, the neutron diffraction technique is used to investigate and compare the residual stress characteristics due to various restraints for a single bead and in fully restrained samples with different numbers of beads. The aim of the research was to characterize the residual stress distribution, which arises in a component during the welding process. The findings have important consequences with respect to design of welding procedures and fitness for purpose assessments.

We conducted a demographic and genetic study to investigate the effects of fragmentation due to the establishment of an exotic softwood plantation on populations of a small marsupial carnivore, the agile antechinus (Antechinus agilis), and the factors influencing the persistence of those populations in the fragmented habitat. The first aspect of the study was a descriptive analysis of patch occupancy and population size, in which we found a patch occupancy rate of 70% among 23 sites in the fragmented habitat compared to 100% among 48 sites with the same habitat characteristics in unfragmented habitat. Mark-recapture analyses yielded most-likely population size estimates of between 3 and 85 among the 16 occupied patches in the fragmented habitat. Hierarchical partitioning and model selection were used to identify geographic and habitat-related characteristics that influence patch occupancy and population size. Patch occupancy was primarily influenced by geographic isolation and habitat quality (vegetation basal area). The variance in population size among occupied sites was influenced primarily by forest type (dominant Eucalyptus species) and, to a lesser extent, by patch area and topographic context (gully sites had larger populations). A comparison of the sex ratios between the samples from the two habitat contexts revealed a significant deficiency of males in the fragmented habitat. We hypothesise that this is due to male-biased dispersal in an environment with increased dispersal-associated mortality. The population size and sex ratio data were incorporated into a simulation study to estimate the proportion of genetic diversity that would have been lost over the known timescale since fragmentation if the patch populations had been totally isolated. The observed difference in genetic diversity (gene diversity and allelic richness at microsatellite and mitochondrial markers) between 16 fragmented and 12 unfragmented sites was extremely low and inconsistent with the isolation of the patch populations. Our results show that although the remnant habitat patches comprise approximately 2% of the study area, they can support non-isolated populations. However, the distribution of agile antechinus populations in the fragmented system is dependent on habitat quality and patch connectivity.

This study investigated burrow use and ranging behaviour in the southern hairy-nosed wombat Lasiorhinus latifrons in semi-arid South Australia. Sixteen adult wombats were fitted with radio transmitters and monitored monthly from July 2001 to February 2002. Wombats generally used between one and five warrens, preferred large warrens with a greater number of entrances and showed a preference for one or two warrens. Across the study period there was no apparent change in burrows used within warrens. Radio-tracking indicated that animals spent very little time above ground (26% of 1115 night-time fixes), centred their activity around their preferred warrens, and moved, on average, 99 m/h and 221 m/night. Mean home-range size, estimated using minimum convex polygons and the harmonic mean method from location data, obtained through triangulation, and daytime warren fixes, ranged from 1.3 to 4.8 ha. Home-range size was similar between males and females and home ranges overlapped substantially. The data highlight the importance of burrows to southern hairy-nosed wombats in shaping their home ranges. It seems likely that the use of burrows and a specialized diet are important energy saving strategies for this species in such unpredictable regions of South Australia.

The martensite aging effect, observed in a number of alloy systems and through which fundamental properties for particular materials are altered by aging in the martensite state, has attracted considerable interest in recent years. It is important to understand and control the effect, particularly in shape-memory alloys for which stability of properties is fundamental to applications. The most likely model, at least for the Au-Cd system in which it has been most critically tested, is the symmetry conforming short-range order (SC-SRO) model first proposed by Ren and Otsika. 197 Au Mossbauer spectroscopy offers the possibility to observe the nature of defects associated with the gold sites. The spectra for single crystal and polycrystalline Au-Cd in both the aged martensite and quenched austenite conditions are presented and discussed. While some uncertainty in interpretation of the spectra remains, particularly in relation to any quadrupole splitting to be expected from either Au atoms on Cd-nearest-neighbour sites or the martensite lattice distortion, the best single-line fits provide evidence for two defect types.

Phonon anomalies in displacive phase transitions have long been suspected to aid the nucleation of the new phase. In materials with strong but incomplete phonon softening, the crystal surface might additionally play an important role, since the enhanced softening of associated surface phonons effectively lowers the nucleation barrier. X-ray scattering under grazing angles is discussed with regard to experimental studies of such phase transitions between 2 and 3 dimensions, as in this geometry all x-ray techniques provide information from a controlled depth below the surface adjustable from nanometers to microns. However, the sensitivity to premonitory phonon softening varies greatly with the scattering technique employed. It is argued that soft modes confined to a narrow interval in q need not show up in the Debye-Waller factor while giving a strong signal in thermal diffuse scattering. Synchrotron radiation data from Ni 2 MnGa provide evidence for this behavior and confirm also the feasibility of depth-resolved studies of the [ζζ0] TA 2 phonon softening.

Substituent alloys of Mg1−xMxB2 with M=Ti, Zr, Mo, Mn, Fe, Ca, Al, Ag, Cu, Y, and Ho and 0⩽x⩽10% have been synthesized by the solid-state reaction. The solid solubility for most of these dopants at Mg site is found to be very low except for M=Al. In most of these alloys, the Vegard relationship holds as the doping level is low. The lattice constants for the fictitious compounds such as AgB2, CuB2, FeB2 have been extrapolated. The superconductivity transition temperature, Tc, shows a systematic changes with the doping level in some of these substituent alloys. Relevant mechanisms of superconductivity suppression have been discussed.

X-ray specular reflectivities of GaAs samples passivated with a thin film of (3-mercaptopropyl)-trimethoxysilane (MPT) have been studied using bending-magnet synchrotron radiation. Various preparation procedures covering etching the GaAs, MPT deposition and its baking have been investigated. An oxide film is always observed between the GaAs and MPT films. The microstructural parameters, such as film thickness, density and interfacial roughness (including the external surface), have been determined from appropriate modeling of the reflectivity. The surface roughness has been compared with a direct measurement using tapping-mode atomic force microscopy. The results are discussed with reference to the potential applications of GaAs as a biosensor.

The microstructure and low-temperature magnetization of nanocrystalline Fe87−xZr7B6Cux and Fe81−xZr7B12Cux alloys (x = 0,1 and 2 at.%) have been studied using a combination of differential scanning calorimetry, x-ray diffraction analysis, transmission electron microscopy and superconducting quantum interference device magnetometry. The results show that the substitution of 1 at.% copper for iron in both low- and high-boron-content alloys has significant effects on the microstructure and magnetic properties, while increasing the copper content to 2 at.% does not cause any further significant change in the microstructure and magnetic properties. For the low-boron-content alloys, the addition of 1 at.% copper promotes a uniform distribution of α-Fe grains, decreases the grain size without changing the phase structure, and decreases the exchange stiffness constant from 180±6 to 122±2 meV A2. For the high-boron-content alloys with the addition of 1 at.% copper, the constitutional crystalline phase changes from a metastable phase with the cubic `Fe12Si2ZrB' structure to the equilibrium phase α-Fe. For the nanocrystalline Fe81Zr7B12 alloy with the metastable phase after being heated to 893 K at 20 K min−1, the saturation magnetization σs(0) = 115±1 emu g−1, and the exchange stiffness constant D = 86±2 meV A2, confirming that the metastable phase is a weaker ferromagnetic phase.

The crystallization behaviour of amorphous Fe93 − x Zr7B x (x = 3, 6, 12 at.%) alloys, the microstructures of the primary crystallization products of stable and metastable phases and the subsequent transformations, have been studied using a combination of differential scanning calorimetry, differential thermal analysis, X-ray diffraction and transmission electron microscopy, including microdiffraction. It has been found that, for x = 3 and 6 at.%, the sole product of primary crystallization is the bcc α-Fe phase and the average grain sizes of the crystalline phase were 14 nm and 12 nm for the two alloys, respectively. However, when x = 12 at.%, primary crystallization results in more than one crystalline phase, and a metastable phase with the cubic “Fe12Si2ZrB” structure is the major crystallization product after the primary crystallization reaction, accompanied by the α-Fe phase. The average grain size of this metastable phase was 35 nm for the alloy heated to 883 K at 20 K/min. Isothermal heat treatments at 873 K and 973 K confirm that after being heated for 240 h, this metastable phase transforms into equilibrium phases: bcc α-Fe, hcp ZrB2 and probably hcp Fe2Zr. The apparent activation energies for the primary crystallization reaction during continuous heating for these three alloys are 4.4 ± 0.2 eV, 3.5 ± 0.2 eV and 6.9 ± 0.3 eV, respectively.

The approach to the saturation magnetization of a nanocrystalline Fe90Zr7B3 alloy has been studied by means of differential magnetic susceptometry. The influence of the microstructure of the alloy on the approach to saturation magnetization has been studied. It has been found that for the optimum heat-treated sample (heated at 923 K for 0.25 h), which had an average grain size of 12 nm and a coercivity, Hc = 6.4 A m-1, the approach to saturation magnetization can be expressed using the law of approach to saturation magnetization, χ = aMsH-2 + 2bMsH-3 + c/2(H-1/2) (where χ is the differential magnetic susceptibility, Ms is the saturation magnetization, H is the magnetic field, and a, b and c are constants), without the H-3 term, while for the sample heated at 923 K for 240 h, which had an average grain size of 82 nm and a coercivity, Hc = 950 A m-1, the approach to saturation magnetization cannot be expressed in the same form. For both samples, the magnetic-anisotropy-related H-3 term cannot be found. As a result, the magnetic anisotropy in this nanocrystalline alloy cannot be determined by using the law of approach to saturation magnetization. The measurement with the differential susceptometer has been compared with the measurement made on the SQUID magnetometer. The result has shown that the measurement of differential susceptibility using a long ribbon sample on the differential susceptometer is more reliable than that using a small sample on the SQUID.

The effect of martensite aging in a Au-49.5%Cd single crystal has been studied using a pushrod dilatometer with various applied stresses. The reverse transformation temperatures, A s and Af, are strongly influenced by the aging time and temperature. The M, and M f temperatures remain constant with aging time, temperature and applied stresses (0 - 0.04 MPa). A critical aging time of approximately 2-3 hours was found to exist for an alloy of this composition and appears to be dependent on the aging temperature.

Previous research on a Ni–37.5at%Al crystal has shown that there are significant differences between the thermal expansion behaviour measured along the three 〈100〉 directions. It was believed that an internal, defect strain field, as a result of the crystal production, served to determine its morphology on cooling it below the martensite start temperature ( M s ). The current research has focused on the effects of an applied biaxial stress on the thermal strain measured along one of these directions. Measurements taken using capacitance dilatometry show that the applied stress has a dramatic effect on the thermal expansion of the crystal, significantly increasing both the thermal strain detected in the martensite phase and the pretransformation strain. The application of biaxial stress was found to modify the martensite morphology significantly. Extensive cracking was observed on the crystal surface as it was cooled through the martensitic transformation.

Optical microscopy has proven to be a useful technique for obtaining general, qualitative information from the entire surface of YBa/sub 2/Cu/sub 3/O/sub 7-x/ samples. Micro-Raman spectroscopy is well suited for routine microstructural analysis of YBCO superconductors. We demonstrate the complementary use of both techniques for the analysis of polycrystalline YBCO. Observed colors of polarisation on YBCO were correlated with information provided by Raman spectroscopy on individual grains to deduce microstructural characteristics across the whole surface of a sample.

OBJECTIVE—To determine whether age, sex, level of deprivation, and area of residence affect the likelihood of investigation and treatment of patients with coronary heart disease. DESIGN, PATIENTS, AND INTERVENTIONS—Routine discharge data were used to identify patients admitted with acute myocardial infarction (AMI) between 1991 and 1993 inclusive. Record linkage provided the proportion undergoing angiography, percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass grafting (CABG) over the following two years. Multiple logistic regression analysis was used to determine whether age, sex, deprivation, and area of residence were independently associated with progression to investigation and revascularisation. SETTING—Mainland Scotland 1991 to 1995 inclusive. MAIN OUTCOME MEASURES—Two year incidence of angiography, PTCA, and CABG. Results—36 838 patients were admitted with AMI. 4831 (13%) underwent angiography, 587 (2%) PTCA, and 1825 (5%) CABG. Women were significantly less likely to undergo angiography (p