Dynamical reduction of the dimensionality of exchange interactions and the "spin-liquid" phase of κ\kappa-(BEDT-TTF)2X_2X

We show that the anisotropy of the effective spin model for the dimer Mott insulator phase of $\kappa$-(BEDT-TTF)$_2X$ salts is dramatically different from that of the underlying tight-binding model. Intra-dimer quantum interference results in a model of coupled spin chains, where frustrated interchain interactions suppress long-range magnetic order. Thus, we argue, the "spin liquid" phase observed in some of these materials is a remnant of the Tomonaga-Luttinger physics of a single chain. This is consistent with previous experiments and resolves some outstanding puzzles. An erratum [Phys. Rev. Lett. 120, 199901 (2018).] is added as an appendix.Comment: Accepted by PRL, 6 pages, 5 figure

Towards mechanomagnetics in elastic crystals: insights from [Cu(acac)2_2]

We predict that the magnetic properties of \cuacac, an elastically flexible crystal, change dramatically when the crystal is bent. We find that unbent \cuacac\ is an almost perfect Tomonaga-Luttinger liquid. Broken-symmetry density functional calculations reveal that the magnetic exchange interactions along the chains is an order of magnitude larger than the interchain exchange. The geometrically frustrated interchain interactions cannot magnetically order the material at any experimentally accessible temperature. The ordering temperature ($T_N$), calculated from the chain random phase approximation, increases by approximately 24 orders of magnitude when the material is bent. We demonstrate that geometric frustration both suppresses $T_N$ and enhances the sensitivity of $T_N$ to bending. In \cuacac, $T_N$ is extremely sensitive to bending, but remains too low for practical applications, even when bent. Partially frustrated materials could achieve the balance of high $T_N$ and good sensitivity to bending required for practical applications of mechanomagnetic elastic crystals

An investigation of children's peer trust across culture: is the composition of peer trust universal?

The components of children's trust in same-gender peers (trust beliefs, ascribed trustworthiness, and dyadic reciprocal trust) were examined in samples of 8- to 11-year-olds from the UK, Italy, and Japan. Trust was assessed by children's ratings of the extent to which same-gender classmates kept promises and kept secrets. Social relations analyses confirmed that children from each country showed significant: (a) actor variance demonstrating reliable individual differences in trust beliefs, (b) partner variance demonstrating reliable individual differences in ascribed trustworthiness, and (c ) relationship variance demonstrating unique relationships between interaction partners. Cultural differences in trust beliefs and ascribed trustworthiness also emerged and these differences were attributed to the tendency for children from cultures that value societal goals to share personal information with the peer group

Sources of variation in the costs of health care for asthma patients in Australia

Objectives: Individuals with chronic conditions, such as asthma, on average incur high health care costs, though good control can reduce costs and improve health outcomes. However, there may be substantial variation between patients in their use of services and therefore costs. Our objective was to investigate the sources of such variation in health system and out-of-pocket costs for people with asthma. Methods: A longitudinal observational study of 252 people with asthma in New SouthWales, Australia, followed for three years, using six-monthly postal surveys and individual administrative data. Factors associated with costs were investigated using generalized linear mixed models. Results: There was substantial variability in costs between individuals but relatively little within-person change over time for the majority. Costs to the health system and out-of-pocket costs were higher with increasing asthma-related health problems and increasing age. Health system costs were less for patients living outside the state capital (Sydney) and for those in the middle income group relative to high and low income groups. Conclusions: Those with poorly-controlled asthma and the elderly require more carefully targeted strategies to improve their health and ensure appropriate use of resources. Access to appropriate services for those living outside of major cities should be improved. Co-payments for the middle-income groups and those living outside major cities should be reduced to improve equity in the use of services. © The Royal Society of Medicine Press Ltd 2009

Clinical and magnetic resonance imaging characteristics of thoracolumbar intervertenral disk extrusions and protrusions in large breed dogs

It has recently been shown that the fat-derived hormone adiponectin has the ability to decrease hyperglycemia and to reverse insulin resistance. However, bacterially produced full-length adiponectin is functionally inactive. Here, we show that endogenous adiponectin secreted by adipocytes is post-translationally modified into eight different isoforms, as shown by two-dimensional gel electrophoresis. Carbohydrate detection revealed that six of the adiponectin isoforms are glycosylated. The glycosylation sites were mapped to several lysines (residues 68, 71, 80, and 104) located in the collagenous domain of adiponectin, each having the surrounding motif of GXKGE(D). These four lysines were found to be hydroxylated and subsequently glycosylated. The glycosides attached to each of these four hydroxylated lysines are possibly glucosylgalactosyl groups. Functional analysis revealed that full-length adiponectin produced by mammalian cells is much more potent than bacterially generated adiponectin in enhancing the ability of subphysiological concentrations of insulin to inhibit gluconeogenesis in primary rat hepatocytes, whereas this insulin-sensitizing ability was significantly attenuated when the four glycosylated lysines were substituted with arginines. These results indicate that full-length adiponectin produced by mammalian cells is functionally active as an insulin sensitizer and that hydroxylation and glycosylation of the four lysines in the collagenous domain might contribute to this activity.link_to_subscribed_fulltex

NOC Liverpool report for the Wirewalker underwater profiler deployment for the RidgeMix research programme

This report provides a review of a ‘wirewalker’ underwater profiler that was used for high resolution water quality and turbulence measurements as part of a mid-Atlantic ocean based scientific survey. The profiler utilised wave energy and buoyancy to generate automated, cyclic underwater vertical measurements. A drifting supporting surface buoy and mooring configuration was used that moved horizontally in response to underwater currents, surface wind and waves, while generating repeated sub-surface vertical scientific measurements. The profiler instrumentation payload included a high-resolution chlorophyll-a fluorimeter, a fast sampling, precision conductivity, temperature and depth sensor (CTD) and a fragile, high resolution oceanic microstructure and turbulence sensor. A bespoke guard was used to help protect the fragile microstructure and turbulence sensors from damage. The mooring surface buoy instrumentation included telemetered GPS at nominally 30 minute intervals, a backup telemetered position indication, a VHF radio beacon based position locator and a solar powered night time light. The experiment was designed to resolve time-variability of upper-ocean mixing and chlorophyll-a fluorescence over the Mid-Atlantic underwater Ridge, an internal wave generation hotspot. Typically more than three wave driven descents to 200 metres and subsequent buoyancy driven ascents to close to the sea surface were achieved per hour during a 22 day deployment, whilst continuously sampling. This represents the first time the UK National Oceanography Centre (NOC) have used this type of underwater profiling system for high resolution oceanic microstructure and turbulence measurements to support a scientific campaign. Information to support a series of developing operational best practices for the use of this delicate and precision sensing arrangement with a wirewalker underwater profiler is provided. Recommendations relating to the future development of this versatile measurement system are also discussed

Events, processes, and the time of a killing

The paper proposes a novel solution to the problem of the time of a killing (ToK), which persistently besets theories of act-individuation. The solution proposed claims to expose a crucial wrong-headed assumption in the debate, according to which ToK is essentially a problem of locating some event that corresponds to the killing. The alternative proposal put forward here turns on recognizing a separate category of dynamic occurents, viz. processes. The paper does not aim to mount a comprehensive defense of process ontology, relying instead on extant defenses. The primary aim is rather to put process ontology to work in diagnosing the current state of play over ToK, and indeed in solving it

Magnetic excitations of the Cu2+^{2+} quantum spin chain in Sr3_3CuPtO6_6

We report the magnetic excitation spectrum as measured by inelastic neutron scattering for a polycrystalline sample of Sr$_3$CuPtO$_6$. Modeling the data by the 2+4 spinon contributions to the dynamical susceptibility within the chains, and with interchain coupling treated in the random phase approximation, accounts for the major features of the powder-averaged structure factor. The magnetic excitations broaden considerably as temperature is raised, persisting up to above 100 K and displaying a broad transition as previously seen in the susceptibility data. No spin gap is observed in the dispersive spin excitations at low momentum transfer, which is consistent with the gapless spinon continuum expected from the coordinate Bethe ansatz. However, the temperature dependence of the excitation spectrum gives evidence of some very weak interchain coupling.Comment: 9 pages, 5 figure