Evolution of changes in carbon monoxide transfer factor in men with chronic obstructive pulmonary disease

SummaryProgression of chronic obstructive pulmonary disease (COPD) has been studied predominantly by following change in forced expiratory volume in 1s (FEV1) which reflects both primary airway disease and associated alveolar disease. Carbon monoxide transfer (Tlco) (the product of the transfer coefficient Kco and alveolar volume Va) is the only simple, widely available test of alveolar function, but few studies have followed long-term changes in an individual.Seventeen middle-aged men with moderate chronic airflow obstruction (mean FEV1 56% of predicted values) were observed with yearly measurements of FEV1, Tlco and Kco over a mean of 18.9yr. At the end of follow-up FEV1 had fallen to 29% of predicted values. Va, measured by single breath dilution, fell in each man. Kco at recruitment ranged from 41% to 110% predicted and remained >75% predicted in eight men at the end of follow-up supporting a phenotype of COPD with predominant airway disease and little emphysema. Fall in FEV1 was faster (2.03% predicted FEV1/yr) in seven men with low initial Kco<75% pred. than in men with initial Kco>75% pred. (1.14% predicted FEV1/yr, P=0.006).Repeated measurements of CO transfer in an individual should increase the present poor knowledge of the contribution of alveolar disease to the progression of chronic airflow obstruction

Fast spin dynamics algorithms for classical spin systems

We have proposed new algorithms for the numerical integration of the equations of motion for classical spin systems. In close analogy to symplectic integrators for Hamiltonian equations of motion used in Molecular Dynamics these algorithms are based on the Suzuki-Trotter decomposition of exponential operators and unlike more commonly used algorithms exactly conserve spin length and, in special cases, energy. Using higher order decompositions we investigate integration schemes of up to fourth order and compare them to a well established fourth order predictor-corrector method. We demonstrate that these methods can be used with much larger time steps than the predictor-corrector method and thus may lead to a substantial speedup of computer simulations of the dynamical behavior of magnetic materials.Comment: 9 pages RevTeX with 8 figure

Marine benthic flora and fauna of Gourdon Bay and the Dampier Peninsula in the Kimberley region of North-Western Australia

Surveys undertaken to characterise the marine benthic habitats along the Dampier Peninsula and further south at Gourdon Bay in the Kimberley region of Western Australia were augmented with epibenthic sled sampling of soft and hard bottom habitats. This paper describes the species collected, their biomass and relative abundance for the main groups of marine macrophytes and invertebrates. Five localities were surveyed; Gourdon Bay, Quondong Point to Coulomb Point, Carnot Bay to Beagle Bay, Perpendicular Head and Packer Island. Sampling was limited to fifteen epibenthic dredge operations from a range of habitat types and was designed to target the most common habitat types and to obtain species identifications of the most important species and those which typified different habitat types. Surveys covered a total of 1,350 m 2 of seabed in depths between 11 and 23m. We identified 415 taxa comprising: 1 seagrass, 43 algae, 52 sponges, 30 ascidians, 10 hydroids, 14 scleractinian corals, 52 other cnidarians, 69 crustaceans, 73 molluscs and 71 echinoderms. Despite the limited nature of the sampling, a significant number of new species, range extensions and new records for Western Australia and Australia were recorded. Within the algae, one range extension (Halimeda cf. cuneata f. digitata not previously recorded in Western Australia) and one possible new species of Areschougia were recorded. Two range extensions were present in the ascidians; the solitary ascidian Polycarpa cf. intonata has previously only been recorded in Queensland and Cnemidocarpa cf. radicosa only in temperate Australian waters. There were several range extensions for the crustacea, for example, the sponge crab, Tumidodromia dormia, has only been recorded in Queensland. One species of holothurian of the genus Phyllophorus could not be identified from the literature available and may represent a new species. Similarly, a small species of the echinoid Gymnechinus could possibly be a new species. The collections of hydroids, hard corals, crinoids and molluscs contained no new species or range extensions. There was difficulty in identification of some groups to species level due to the status of the current taxonomic literature (e.g. Cnidaria, Porifera and ascidians) and there may be a number of new species among the material collected. Among the anthozoa, there is at least one new species of Chromonephthea and potentially 10 range extensions to Western Australia. Sinularia cf. acuta and Chromonephthea curvata are both new records for Australia with both previously recorded in Indonesia only. Among the better known taxa (e.g. molluscs, echinoderms, corals), most of the taxa identified to species level have been recorded to occur throughout north-western Australia, however the diversity recorded in this study is less than other parts of the Kimberley and this is almost certainly a result of the small overall area sampled and the single method of collection utilised. The most important species on soft bottom habitats in terms of biomass was the heart urchin Breynia desorii (up to 326 g.m -2). Sponges were the dominant fauna by biomass (up to 620 g.m -2) on hard bottom habitats and biomass was dominated a by a few large cup and massive sponge species (e.g. Pione velans and two unidentified Spheciospongia). The biomass of other filter feeders, especially ascidians (e.g. Aplidium cf. crateriferum), soft corals (e.g. Chromonephthea spp.), gorgonians (e.g. Junceella fragilis and Dichotella gemmacea) was also high, indicating the importance of these groups in characterising hard bottom habitats. Although low in biomass, crinoids such as Comaster multifidus and Comatula pectinata were abundant in samples that included a high biomass of other filter feeders

Heritage, affect and emotion : politics, practices and infrastructures.

Heritage and its economies are driven by affective politics and consolidated through emotions such as pride, awe, joy and pain. In the humanities and social sciences, there is a widespread acknowledgement of the limits not only of language and subjectivity, but also of visuality and representation. Social scientists, particularly within cultural geography and cultural studies, have recently attempted to define and understand that which is more-than-representational, through the development of theories of affect, assemblage, post-humanism and actor network theory, to name a few. While there have been some recent attempts to draw these lines of thinking more forcefully into the field of heritage studies, this book focuses for the first time on relating heritage with the politics of affect. The volume argues that our engagements with heritage are almost entirely figured through the politics of affective registers such as pain, loss, joy, nostalgia, pleasure, belonging or anger. It brings together a number of contributions that collectively - and with critical acuity - question how researchers working in the field of heritage might begin to discover and describe affective experiences, especially those that are shaped and expressed in moments and spaces that can be, at times, intensely personal, intimately shared and ultimately social. It explores current theoretical advances that enable heritage to be affected, released from conventional understandings of both ’heritage-as-objects’ and ’objects-as-representations’ by opening it up to a range of new meanings, emergent and formed in moments of encounter. Whilst representational understandings of heritage are by no means made redundant through this agenda, they are destabilized and can thus be judged anew in light of these developments. Each chapter offers a novel and provocative contribution, provided by an interdisciplinary team of researchers who are thinking theoretically about affect through landscapes, practices of commemoration, visitor experience, site interpretation and other heritage work

Synchronously pumped mid-infrared CdSe optical parametric oscillator

Synchronously pumped optical parametric oscillators (SPOPOs) are efficient sources of tunable ultrashort pulses, with low threshold average power requirements, since gain is defined by peak power. An attractive material for such devices is cadmium selenide (CdSe) due to its high nonlinearity (d(31) = 18 pm/V), wide transparency range (0.75-25 µm) and high optical quality. Previous efforts involving CdSe in OPOs have been restricted to angle-tuning, and using Q-switched pump sources. We present here the first continuous-wave, mode-locked SPOPO based on non-critically phase-matched (NCPM) CdSe, with agile tuning of the idler over the range 9.1-9.7 µm, the longest wavelength achieved using a SPOPO to date. Pump-wavelength-tuning over a wide range (necessary for the NCPM arrangement) was provided by the signal output of a periodically poled lithium niobate (PPLN) SPOPO, operating close to degeneracy using a single PPLN grating period. The use of a diffraction grating to tune the signal of the PPLN SPOPO was a key factor in obtaining clean, single-frequency pump conditions, with tuning achieved by simple grating rotation

A unified approach to Performance Assessment (PA) of geological CO2 storage

AbstractPerformance Assessment (PA) evaluates the effectiveness of a specified system or sub-system relative to some criteria of interest to particular stakeholders. A flexible PA approach has been developed for geological CO2 storage, by which qualitative information, quantitative data, output from numerical models and expert judgments are combined within a decision-support framework. The methodology has been implemented in three software tools: (1) TESLA, which is used to construct decision trees, propagate evidence and record the logic underlying a decision; (2) an on-line database of Features, Events and Processes (FEPs) targeted at CO2 storage; and (3) QPAC-CO2, for modelling system performance

Modeling DNA Structure, Elasticity and Deformations at the Base-pair Level

We present a generic model for DNA at the base-pair level. We use a variant of the Gay-Berne potential to represent the stacking energy between neighboring base-pairs. The sugar-phosphate backbones are taken into account by semi-rigid harmonic springs with a non-zero spring length. The competition of these two interactions and the introduction of a simple geometrical constraint leads to a stacked right-handed B-DNA-like conformation. The mapping of the presented model to the Marko-Siggia and the Stack-of-Plates model enables us to optimize the free model parameters so as to reproduce the experimentally known observables such as persistence lengths, mean and mean squared base-pair step parameters. For the optimized model parameters we measured the critical force where the transition from B- to S-DNA occurs to be approximately $140{pN}$. We observe an overstretched S-DNA conformation with highly inclined bases that partially preserves the stacking of successive base-pairs.Comment: 15 pages, 25 figures. submitted to PR

Topological Defects and CMB anisotropies : Are the predictions reliable ?

We consider a network of topological defects which can partly decay into neutrinos, photons, baryons, or Cold Dark Matter. We find that the degree-scale amplitude of the cosmic microwave background (CMB) anisotropies as well as the shape of the matter power spectrum can be considerably modified when such a decay is taken into account. We conclude that present predictions concerning structure formation by defects might be unreliable.Comment: 14 pages, accepted for publication in PR

Grain Surface Models and Data for Astrochemistry

AbstractThe cross-disciplinary field of astrochemistry exists to understand the formation, destruction, and survival of molecules in astrophysical environments. Molecules in space are synthesized via a large variety of gas-phase reactions, and reactions on dust-grain surfaces, where the surface acts as a catalyst. A broad consensus has been reached in the astrochemistry community on how to suitably treat gas-phase processes in models, and also on how to present the necessary reaction data in databases; however, no such consensus has yet been reached for grain-surface processes. A team of ∼25 experts covering observational, laboratory and theoretical (astro)chemistry met in summer of 2014 at the Lorentz Center in Leiden with the aim to provide solutions for this problem and to review the current state-of-the-art of grain surface models, both in terms of technical implementation into models as well as the most up-to-date information available from experiments and chemical computations. This review builds on the results of this workshop and gives an outlook for future directions