Continuous Elastic Phase Transitions in Pure and Disordered Crystals

We review the theory of second--order (ferro--)elastic phase transitions, where the order parameter consists of a certain linear combination of strain tensor components, and the accompanying soft mode is an acoustic phonon. In three--dimensional crystals, the softening can occur in one-- or two--dimensional soft sectors. The ensuing anisotropy reduces the effect of fluctuations, rendering the critical behaviour of these systems classical for a one--dimensional soft sector, and classical with logarithmic corrections in case of a two--dimensional soft sector. The dynamical critical exponent is $z = 2$, and as a consequence the sound velocity vanishes as $c_s \propto | T - T_c |^{1/2}$, while the phonon damping coefficient is essentially temperature--independent. Disorder may lead to a variety of precursor effects and modified critical behaviour. Defects that locally soften the crystal may induce the phenomenon of local order parameter condensation. When the correlation length of the pure system exceeds the average defect separation $n_{\rm D}^{-1/3}$, a disorder--induced phase transition to a state with non--zero average order parameter can occur at a temperature $T_c(n_{\rm D})$ well above the transition temperature $T_c^0$ of the pure crystal. Near $T_c^0$, the order--parameter curve, susceptibility, and specific heat appear rounded. For $T < T_c(n_{\rm D})$ the spatial inhomogeneity induces a static central peak with finite $q$ width in the scattering cross section, accompanied by a dynamical component that is confined to the very vicinity of the disorder--induced phase transition.Comment: 26 pages, Latex (rs.sty now IS included), 11 figures can be obtained from U.C. T\"auber ([email protected]); will appear in Phil. Trans. Roy. Soc. Lond. A (October 1996

Deglacial landform assemblage records fast ice-flow and retreat, Inner Hebrides, Scotland

High-resolution bathymetric data have been central to recent advances in the understanding of past dynamics of the former British–Irish Ice Sheet (BIIS). As approximately two-thirds of the former BIIS was probably marine-based during the Last Glacial Maximum (LGM) (c. 29–23 ka), geomorphic observations of the seabed are required increasingly to understand the extent, pattern and timing of past glaciation. Until recently, glacial reconstructions for the Inner Hebrides, offshore of western Scotland, have been based primarily on terrestrial observations. Previous workers have proposed generalized reconstructions in which the Inner Hebrides are located within a significant former ice-sheet flow pathway that drained the western Scottish sector of the BIIS, feeding the Barra Fan during the LGM and earlier glaciations (Fig. 1). Results from numerical ice-sheet modelling suggest that former ice-flow velocities within the region were on the order of hundreds to thousands of metres per year, but yield further insight by demonstrating how dynamic binge/purge cycles may have affected ice-sheet mass balance over time (Hubbard et al. 2009). Following the LGM, ice-sheet retreat through the area is estimated to have been in the order of 20 m per year (Clark et al. 2012). Here we present swath-bathymetric data from the Inner Hebrides that provide in situ constraints on ice-sheet flow and subsequent retreat dynamics from within this important sector of the BIIS

Furrow application of insecticide as a method of controlling wireworms in potato land

Three methods of applying insecticides for the control of the wireworm, &lt;i&gt;Agriotes obscurus&lt;/i&gt; L.. were tested using fonofos and terbufos. Most treatments gave significantly more marketable tubers than the control. The furrow treatment gave more consistent results than broadcast or side-dress and, at 1.1 or 2.2 kg a.i/ha, gave control equal to, or better than, the broadcast treatment at 5.6 kg a.i./ha. Analyses by gas chromatography using a flame photometric detector for residues in potatoes grown in treated soil showed residues to be less than 0.02 ppm

Heat Capacity in Magnetic and Electric Fields Near the Ferroelectric Transition in Tri-Glycine Sulfate

Specific-heat measurements are reported near the Curie temperature ($T_C$~= 320 K) on tri-glycine sulfate. Measurements were made on crystals whose surfaces were either non-grounded or short-circuited, and were carried out in magnetic fields up to 9 T and electric fields up to 220 V/cm. In non-grounded crystals we find that the shape of the specific-heat anomaly near $T_C$ is thermally broadened. However, the anomaly changes to the characteristic sharp $\lambda$-shape expected for a continuous transition with the application of either a magnetic field or an electric field. In crystals whose surfaces were short-circuited with gold, the characteristic $\lambda$-shape appeared in the absence of an external field. This effect enabled a determination of the critical exponents above and below $T_C$, and may be understood on the basis that the surface charge originating from the pyroelectric coefficient, $dP/dT$, behaves as if shorted by external magnetic or electric fields.Comment: 4 Pages, 4 Figures. To Appear in Applied Physics Letters_ January 200

Efficacy of insecticides against tuber flea beetles, wireworms and aphids in potatoes

Soil-incorporated and foliar-applied insecticides, alone and in combination, were tested in silt loam to control tuber flea beetle, Epitrix tuberis Gent., the green peach aphid, Myzus persicae (Sulz.) and the wireworm Agriotes obscurus (L.) Most soil-incorporated band treatments did not give adequate protection from tuber flea beetles. However, supplemental foliar applications, July 15 and 30 and August 15, reduced the percentage unmarketable tubers to 13% under a heavy infestation in 1977 and to 0% in a lighter infestation in 1978. Fonofos, broadcast and soil-incorporated, gave the best control of wireworms and of a light infestation of tuber flea beetles. Methamidophos was the best aphicid

Respectable Drinkers, Sensible Drinking, Serious Leisure: Single-Malt Whisky Enthusiasts and the Moral Panic of Irresponsible Others

In the public discourse of policy-makers and journalists, drinkers of (excessive) alcohol are portrayed either as irresponsible, immoral deviants or as gullible victims. In other words, the public discourse engenders a moral panic about alcohol-crazed individuals, who become what Cohen [1972. Folk devil and moral panics. London: Routledge] identifies as folk devils: the Other, abusing alcohol to create anti-social disorder. However, alcohol-drinking was, is and continues to be an everyday practice in the leisure lives of the majority of people in the UK. In this research article, I want to explore the serious leisure of whisky-tasting to provide a counter to the myth of the alcohol-drinker as folk devil, to try to construct a new public discourse of sensible drinking. I will draw on ethnographic work at whisky-tastings alongside interviews and analysis of on-line discourses. I show that participation in whisky-tasting events creates a safe space in which excessive amounts of alcohol are consumed, yet the norms of the particular habitus ensure that such drinking never leads to misbehaviour. In doing so, however, I will note that the respectability of whisky-drinking is associated with its masculine, white, privileged habitus – the folk devil becomes someone else, someone Other

“No One Manages It; We Just Sign Them Up and Do It”: A Whole System Analysis of Access to Healthcare in One Remote Australian Community

Objective: To assess the accessibility, availability and utilisation of a comprehensive range of community-based healthcare services for Aboriginal people and describe contributing factors to providing effective healthcare services from the provider perspective. Setting: A remote community in New South Wales, Australia. Participants: Aboriginal and non-Aboriginal health and education professionals performing various roles in healthcare provision in the community. Design: Case study. Methodology: The study was co-designed with the community. A mixed-methods methodology was utilised. Data were gathered through structured interviews. Descriptive statistics were used to analyse the availability of 40 health services in the community, whilst quotations from the qualitative research were used to provide context for the quantitative findings. Results: Service availability was mapped for 40 primary, specialised, and allied health services. Three key themes emerged from the analysis: (1) there are instances of both underservicing and overservicing which give insight into systemic barriers to interagency cooperation; (2) nurses, community health workers, Aboriginal health workers, teachers, and administration staff have an invaluable role in healthcare and improving patient access to health services and could be better supported through further funding and opportunities for specialised training; and (3) visiting and telehealth services are critical components of the system that must be linked to existing community-led primary care services. Conclusion: The study identified factors influencing service availability, accessibility and interagency cooperation in remote healthcare services and systems that can be used to guide future service and system planning and resourcing

UK Quaternary : mapping and modelling the Quaternary - meeting our stakeholder needs

• This report provides an assessment of the strategic significance of Quaternary geology relative to the British Geological Survey (BGS) and its range of UK stakeholders. The report examines the type of information, data and knowledge that is required by our stakeholders and proposes a vision for how BGS will the tackle the Quaternary to deliver this. •The Quaternary – the last 2.588 Ma of geological time – is one of the most critical parts of the UK geological record. The Quaternary coincides with the geology that occurs in much of the shallow sub-surface. It reflects the part of the geological record most frequently interacted with and utilised by humans, but also the part of the geological record most impacted (buried, eroded and deformed) by the wide range of geological processes that operated during the Quaternary. • The geological record of the Quaternary is marked by a distinctive variability and heterogeneity that poses significant challenges and risks for BGS stakeholders. Improving our data, knowledge and understanding of this critical part of the geological record is important to help our stakeholders understand and mitigate against geological risks and to inform better planning and decision making. • BGS has a proven track record of characterising the Quaternary, but our approaches need to evolve to meet the demands provided by: (1) new geological knowledge and understanding; (2) the improved access to increasingly better-quality digital data; (3) the availability of new analytical techniques that enable us to characterise the geology and uncertainty more effectively and quantitatively; and (4) our stakeholder need for quality information, data and guidance at multiple spatial scales. • In this report we make several strategic recommendations for how our approach to the Quaternary can evolve and how this can be communicated to stakeholders most effectively. We consider that this should occur through the modernisation of the Quaternary Domains dataset; the development of new approaches to classifying and characterising the Quaternary; and the requirement for a spatial dataset or data matrix for storing and managing corporate data and information

Nonlinear optical spectroscopy and two-photon excited fluorescence spectroscopy reveal the excited states of fluorophores embedded in a beetle's elytra

This is the author accepted manuscript. The final version is available via the DOI in this record.Upon illumination by ultraviolet light, many animal species emit light through fluorescence processes arising from fluorophores embedded within their biological tissues. Fluorescence studies in living organisms are however relatively scarce and so far limited to the linear regime. Multiphoton excitation fluorescence analyses as well as nonlinear optical techniques offer unique possibilities to investigate the effects of the local environment on the excited states of fluorophores. Herein, these techniques are applied for the first time to study of the naturally controlled fluorescence in insects. The case of the male Hoplia coerulea beetle is investigated because the scales covering the beetle's elytra are known to possess an internal photonic structure with embedded fluorophores, which controls both the beetle's coloration and the fluorescence emission. An intense two-photon excitation fluorescence signal is observed, the intensity of which changes upon contact with water. A third-harmonic generation signal is also detected, the intensity of which depends on the light polarization state. The analysis of these nonlinear optical and fluorescent responses unveils the multi-excited states character of the fluorophore molecules embedded in the beetle's elytra. The role of form anisotropy in the photonic structure, which causes additional tailoring of the beetle's optical responses, is demonstrated by circularly polarized light and nonlinear optical measurements.Wallonia–Brussels InternationalBelgian National Fund for Scientific Research2018 Biomimetics Travel AwardFWO FlandersHercules FoundationAction de Recherche ConcerteNanoscale Quantum OpticsFRSFNRSMinistry of Science, Republic of Serbi