159 research outputs found

    Holidays, celebrations, and commiserations: measuring drinking during feasting and fasting to improve national and individual estimates of alcohol consumption

    Get PDF
    BACKGROUND: Accurate measures of alcohol consumption are critical in assessing health harms caused by alcohol. In many countries, there are large discrepancies between survey-based measures of consumption and those based on alcohol sales. In England, surveys measuring typical alcohol consumption account for only around 60% of alcohol sold. Here, using a national survey, we measure both typical drinking and atypical/special occasion drinking (i.e., feasting and fasting) in order to develop more complete measures of alcohol consumption. METHODS: A national random probability telephone survey was implemented (May 2013 to April 2014). Inclusion criteria were resident in England and aged 16 years or over. Respondents (n = 6,085) provided information on typical drinking (amounts per day, drinking frequency) and changes in consumption associated with routine atypical days (e.g., Friday nights) and special dinking periods (e.g., holidays) and events (e.g., weddings). Generalized linear modelling was used to identify additional alcohol consumption associated with atypical/special occasion drinking by age, sex, and typical drinking level. RESULTS: Accounting for atypical/special occasion drinking added more than 120 million UK units of alcohol/week (~12 million bottles of wine) to population alcohol consumption in England. The greatest impact was seen among 25- to 34-year-olds with the highest typical consumption, where atypical/special occasions added approximately 18 units/week (144 g) for both sexes. Those reporting the lowest typical consumption (≤1 unit/week) showed large relative increases in consumption (209.3%) with most drinking associated with special occasions. In some demographics, adjusting for special occasions resulted in overall reductions in annual consumption (e.g., females, 65 to 74 years in the highest typical drinking category). CONCLUSIONS: Typical drinking alone can be a poor proxy for actual alcohol consumption. Accounting for atypical/special occasion drinking fills 41.6% of the gap between surveyed consumption and national sales in England. These additional units are inevitably linked to increases in lifetime risk of alcohol-related disease and injury, particularly as special occasions often constitute heavy drinking episodes. Better population measures of celebratory, festival, and holiday drinking are required in national surveys in order to adequately measure both alcohol consumption and the health harms associated with special occasion drinking

    Competing interactions in the XYZ model

    Get PDF
    We study the interplay between a XY anisotropy γ\gamma, exchange modulations and an external magnetic field along the z direction in the XYZ chain using bosonization and Lanczos diagonalization techniques. We find an Ising critical line in the space of couplings which occur due to competing relevant perturbations which are present. More general situations are also discussed.Comment: 6 pages, 6 figure

    Entanglement in the quantum Ising model

    Full text link
    We study the asymptotic scaling of the entanglement of a block of spins for the ground state of the one-dimensional quantum Ising model with transverse field. When the field is sufficiently strong, the entanglement grows at most logarithmically in the number of spins. The proof utilises a transformation to a model of classical probability called the continuum random-cluster model, and is based on a property of the latter model termed ratio weak-mixing. Our proof applies equally to a large class of disordered interactions

    Adsorption of Reactive Particles on a Random Catalytic Chain: An Exact Solution

    Full text link
    We study equilibrium properties of a catalytically-activated annihilation A+A→0A + A \to 0 reaction taking place on a one-dimensional chain of length NN (N→∞N \to \infty) in which some segments (placed at random, with mean concentration pp) possess special, catalytic properties. Annihilation reaction takes place, as soon as any two AA particles land onto two vacant sites at the extremities of the catalytic segment, or when any AA particle lands onto a vacant site on a catalytic segment while the site at the other extremity of this segment is already occupied by another AA particle. Non-catalytic segments are inert with respect to reaction and here two adsorbed AA particles harmlessly coexist. For both "annealed" and "quenched" disorder in placement of the catalytic segments, we calculate exactly the disorder-average pressure per site. Explicit asymptotic formulae for the particle mean density and the compressibility are also presented.Comment: AMSTeX, 27 pages + 4 figure

    Jordan-Wigner approach to dynamic correlations in spin-ladders

    Full text link
    We present a method for studying the excitations of low-dimensional quantum spin systems based on the Jordan-Wigner transformation. Using an extended RPA-scheme we calculate the correlation function of neighboring spin flips which well approximates the optical conductivity of Sr2CuO3{\rm Sr_2CuO_3}. We extend this approach to the two-leg S=1/2S=1/2--ladder by numbering the spin operators in a meander-like sequence. We obtain good agreement with the optical conductivity of the spin ladder compound (La,Ca)14_{14}Cu24_{24}O41_{41} for polarization along the rungs. For polarization along the legs higher order correlations are important to explain the weight of high-energy continuum excitations and we estimate the contribution of 4-- and 6--fermion processes.Comment: 15 pages, 16 figure

    Structural and dielectric properties of Sr2_{2}TiO4_{4} from first principles

    Full text link
    We have investigated the structural and dielectric properties of Sr2_{2}TiO4_{4},the first member of the Srn+1_{n+1}Tin_{n}O3n+1_{3n+1} Ruddlesden-Popper series, within density functional theory. Motivated by recent work in which thin films of Sr2_{2}TiO4_{4} were grown by molecular beam epitaxy (MBE) on SrTiO3_{3} substrates, the in-plane lattice parameter was fixed to the theoretically optimized lattice constant of cubic SrTiO3_{3} (n=∞\infty), while the out-of-plane lattice parameter and the internal structural parameters were relaxed. The fully relaxed structure was also investigated. Density functional perturbation theory was used to calculate the zone-center phonon frequencies, Born effective charges, and the electronic dielectric permittivity tensor. A detailed study of the contribution of individual infrared-active modes to the static dielectric permittivity tensor was performed. The calculated Raman and infrared phonon frequencies were found to be in agreement with experiment where available. Comparisons of the calculated static dielectric permittivity with experiments on both ceramic powders and epitaxial thin films are discussed.Comment: 11 pages, 1 figure, 8 tables, submitted to Phys. Rev.

    Geochemical and physical sources of radon variation in a subterranean estuary — implications for groundwater radon activities in submarine groundwater discharge studies

    Get PDF
    Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Chemistry 110 (2008): 120-127, doi:10.1016/j.marchem.2008.02.011.Submarine groundwater discharge (SGD), in form of springs and diffuse seepage, has long been recognized as a source of chemical constituents to the coastal ocean. Because groundwater is two to four orders of magnitude richer in radon than surface water, it has been used as both a qualitative and a quantitative tracer of groundwater discharge. Besides this large activity gradient, the other perceived advantage of radon stems from its classification as noble gas; that is, its chemical behavior is expected not to be influenced by salinity, redox, and diagenetic conditions present in aquatic environments. During our three-year monthly sampling of the subterranean estuary (STE) in Waquoit Bay, MA, we found highly variable radon activities (50-1600 dpm L-1) across the fresh-saline interface of the aquifer. We monitored pore water chemistry and radon activity at 8 fixed depths spanning from 2 to 5.6 m across the STE, and found seasonal fluctuations in activity at depths where elevated radon was observed. We postulate that most of pore water 222Rn is produced from particle-surface bound 226Ra, and that the accumulation of this radium is likely regulated by the presence of manganese (hydr)oxides. Layers of manganese (hydr)oxides form at the salinity transition zone (STZ), where water with high salinity, high manganese, and low redox potential mixes with fresh water. Responding to the seasonality of aquifer recharge, the location of the STZ and the layers with radium enriched manganese (hydr)oxide follows the seasonal land- or bay-ward movement of the freshwater lens. This results in seasonal changes in the depth where elevated radon activities are observed. The conclusion of our study is that the freshwater part of the STE has a radon signature that is completely different from the STZ or recirculated sea water. Therefore, the radon activity in SGD will depend on the ratio of fresh and recirculated seawater in the discharging groundwater.This work is a result of research sponsored by NSF (OCE- 0425061 to M.A.C.) and the WHOI Postdoctoral Scholar program (to H.D.)

    Felsic crust development in the Kaapvaal Craton, South Africa: A reference sample collection to investigate a billion years of geological history

    Get PDF
    The crust of the Kaapvaal craton accreted throughout the Archaean over nearly 1 billion years. It provides a unique example of the various geological processes that shape Earth's continental crust, and is illustrated by a reference collection of granitoids and mafic rocks (SWASA collection). This sample collection is fully characterised in term of age, major and trace elements, and documents the following multistage history of the craton. In the Barberton area, the initial stages of accretion (stage B·I, > 3.33 Ga and B.II, 3.28—3.21 Ga) correspond to the formation of a sodic (TTG) crust extracted from a near-chondritic reservoir. Stage B.III (ca. 3.1 Ga) corresponds to reworking of this crust, either through intracrustal melting, or via recycling of some material into the mantle and melting of this enriched mantle. Stage B.IV (2.85—2.7 Ga) corresponds to the emplacement of small, discrete plutons involving limited intracrustal reworking. The Northern Kaapvaal craton corresponds to a mobile belt flanking the Barberton cratonic core to the North. Stage NK·I (> 3.1 Ga) resembles stages B·I and B.II: formation of a TTG crust from a chondritic reservoir. In contrast, stage NK.II. (2.97–2.88 Ga) witnesses probable rifting of a cratonic fragment and formation of greenstone basins as well as a new generation of TTGs with both the mafic and felsic magmatism extracted from an isotopically depleted mantle (super-chondritic) reservoir. Intra-crustal reworking dominates stage NK.III (2.88–2.71 Ga), whereas sanukitoids and related granites, involving a mantle contaminated by recycled crustal material, are common during stage NK.IV (ca. 2.67 Ga)

    Quantum Griffiths effects and smeared phase transitions in metals: theory and experiment

    Full text link
    In this paper, we review theoretical and experimental research on rare region effects at quantum phase transitions in disordered itinerant electron systems. After summarizing a few basic concepts about phase transitions in the presence of quenched randomness, we introduce the idea of rare regions and discuss their importance. We then analyze in detail the different phenomena that can arise at magnetic quantum phase transitions in disordered metals, including quantum Griffiths singularities, smeared phase transitions, and cluster-glass formation. For each scenario, we discuss the resulting phase diagram and summarize the behavior of various observables. We then review several recent experiments that provide examples of these rare region phenomena. We conclude by discussing limitations of current approaches and open questions.Comment: 31 pages, 7 eps figures included, v2: discussion of the dissipative Ising chain fixed, references added, v3: final version as publishe
    • …
    corecore