ASAS/WHO ICF Core Sets for ankylosing spondylitis (AS): how to classify the impact of AS on functioning and health

Objective: To report on the results of a standardised consensus process agreeing on concepts typical and/or relevant when classifying functioning and health in patients with ankylosing spondylitis (AS) based on the International Classification of Functioning and Health (ICF).Methods: Experts in AS from different professional and geographical backgrounds attended a consensus conference and were divided into three working groups. Rheumatologists were selected from members of the Assessment of SpondyloArthritis international Society (ASAS). Other health professionals were recommended by ASAS members. The aim was to compose three working groups with five to seven participants to allow everybody's contribution in the discussions. Experts selected ICF categories that were considered typical and/or relevant for AS during a standardised consensus process by integrating evidence from preceding studies in alternating working group and plenary discussions. A Comprehensive ICF Core Set was selected for the comprehensive classification of functioning and a Brief ICF Core Set for application in trials.Results: The conference was attended by 19 experts from 12 countries. Eighty categories were included in the Comprehensive Core Set, which included 23 Body functions, 19 Body structures, 24 Activities and participation and 14 Environmental factors. Nineteen categories were selected for the Brief Core Set, which included 6 Body functions, 4 Body structures, 7 Activities and participation and 2 Environmental factors.Conclusion: The Comprehensive and Brief ICF Core Sets for AS are now available and aim to represent the external reference to define consequences of AS on functioning

Benthic Foraminifera biomass production in the western Baltic

The biomass (weight of protoplasm) and production of the major species of benthic Foraminifera was calculated for the "Hausgarten" area of Sonderforschungsbereich 95. Data from 440 samples collected between 1971 and 1975 were used for these calculations. Biomass production of Foraminifera is 10-90 mg wet weight/m2/y in the turbulent zone and up to 5411 mg/m2/y in the basins. Epiphytic species produce 13-26 mg wet weight/m2/y. These values are higher than those recorded in the literature with the exception of the subarctic. The foraminiferal proportion of total meiobenthos biomass ranges between 6% in the turbulent zone and 63% in the basin

Diatom and silicoflagellate fluxes at the Walvis Ridge: An environment influenced by coastal upwelling in the Benguela system

Seasonal fluctuations in the total particle, biogenic opal, diatom and silicoflagellate fluxes were observed in sediment traps deployed at 599 m and 1648 m in the Walvis Ridge area, within the Benguela upwelling system, from March 1989 to March 1990 (station WR 2: 20°02.8′S, 09°09.3′E). Fluxes were directly related to wind stress variations (wind maxima preceding flux maxima by several weeks), and inversely related to SST changes (derived from measured concentrations of C37 alkenones; range: 14.6°–23.6°C). The biogenic particle composition at different depths reflected the complicated hydrology of the area with a combination of tropical, temperate and subantarctic water masses. Biogenic opal content varied from about 2 to 12% of the total mass flux in the upper trap and from about 4 to 17% in the lower trap. Diatoms were the main contributor to the opal fraction (mean daily flux of ca. 5.5 * 106 valves m−2 day−1), followed by silicoflagellates (ca. 2.6 * 105 skeletons m−2 day−1). Two seasonal maxima, in May and June (austral autumn) and from October to November (austral spring), were observed; silicoflagellates yielded also a third moderate maximum in August/September (austral winter). At 1648 m fluxes peaked from May to July (data were available for the period 18 Mar to 27 Aug 1989 only). Few diatoms were abundant; 19 taxa accounted for 50% of all the diatoms identified, and about 32 for the 75% level. Specific diversity of diatoms at 599 m was highest during times of lowest fluxes, in the austral winter, late spring and summer. The diatom taxa occurring at 599 m and at 1648 m were the same, with some flux enrichment with depth due to advection of particles into the lower trap by resuspension and downslope movement. The relatively high concentrations of the Antarctic-Subantarctic species Fragilariopsis kerguelensis in the upper trap solely, was probably linked to selective entrainment and transport within a ring of southerly origin (south of the Subantarctic/Subtropical Convergence Zone). The enrichment of moderately resistant and robust taxa in the sediments in conjunction with the rarity or absence of delicate taxa points to preferential concentration in the sediments of some taxa and dissolution of others. The occurrence of phytoliths in the traps and in the sediment sample can be linked to the “berg” winds, which are typical for the entire Benguela region during fall and winter

The Nonlinear Dynamic Conversion of Analog Signals into Excitation Patterns

Local periodic perturbations induce frequency-dependent propagation waves in an excitable spatio-temporally chaotic system. We show how segments of noise-contaminated and chaotic perturbations induce characteristic sequences of excitations in the model system. Using a set of tuned excitable systems, it is possible to characterize signals by their spectral composition of excitation pattern. As an example we analyze an epileptic spike-and-wave time series.Comment: 14 pages, 5 figure

Perfect magnetohydrodynamics as a field theory

We propose the generally covariant action for the theory of a self-coupled complex scalar field and electromagnetism which by virtue of constraints is equivalent, in the regime of long wavelengths, to perfect magnetohydrodynamics (MHD). We recover from it the Euler equation with Lorentz force, and the thermodynamic relations for a prefect fluid. The equation of state of the latter is related to the scalar field's self potential. We introduce 1+3 notation to elucidate the relation between MHD and field variables. In our approach the requirement that the scalar field be single valued leads to the quantization of a certain circulation in steps of $\hbar$; this feature leads, in the classical limit, to the conservation of that circulation. The circulation is identical to that in Oron's generalization of Kelvin's circulation theorem to perfect MHD; we here characterize the new conserved helicity associated with it. We also demonstrate the existence for MHD of two Bernoulli-like theorems for each spacetime symmetry of the flow and geometry; one of these is pertinent to suitably defined potential flow. We exhibit the conserved quantities explicitly in the case that two symmetries are simultaneously present, and give examples. Also in this case we exhibit a new conserved MHD circulation distinct from Oron's, and provide an example.Comment: RevTeX, 16 pages, no figures; clarifications added and typos corrected; version to be published in Phys. Rev.

Theory of temperature dependence of the Fermi surface-induced splitting of the alloy diffuse-scattering intensity peak

The explanation is presented for the temperature dependence of the fourfold intensity peak splitting found recently in diffuse scattering from the disordered Cu3Au alloy. The wavevector and temperature dependence of the self-energy is identified as the origin of the observed behaviour. Two approaches for the calculation of the self-energy, the high-temperature expansion and the alpha-expansion, are proposed. Applied to the Cu3Au alloy, both methods predict the increase of the splitting with temperature, in agreement with the experimental results.Comment: 4 pages, 3 EPS figures, RevTeX, submitted to J. Phys. Condens. Matter (Letter to the Editor

Impacts of land-use and land-cover change on stream hydrochemistry in the Cerrado and Amazon biomes

Studies on the impacts of land-use and land-cover change on stream hydrochemistry in active deforestation zones of the Amazon agricultural frontier are limited and have often used low-temporal-resolution datasets. Moreover, these impacts are not concurrently assessed in well-established agricultural areas and new deforestations hotspots. We aimed to identify these impacts using an experimental setup to collect high-temporal-resolution hydrological and hydrochemical data in two pairs of low-order streams in catchments under contrasting land use and land cover (native vegetation vs. pasture) in the Amazon and Cerrado biomes. Our results indicate that the conversion of natural landscapes to pastures increases carbon and nutrient fluxes via streamflow in both biomes. These changes were the greatest in total inorganic carbon in the Amazon and in potassium in the Cerrado, representing a 5.0- and 5.5-fold increase in the fluxes of each biome, respectively. We found that stormflow, which is often neglected in studies on stream hydrochemistry in the tropics, plays a substantial role in the carbon and nutrient fluxes, especially in the Amazon biome, as its contributions to hydrochemical fluxes are mostly greater than the volumetric contribution to the total streamflow. These findings demonstrate that assessments of the impacts of deforestation in the Amazon and Cerrado biomes should also take into account rapid hydrological pathways; however, this can only be achieved through collection of high-temporal-resolution data

Cholesterol sensing by CD81 is important for hepatitis C virus entry

CD81 plays a role in a variety of physiological and pathological processes. Recent structural analysis of CD81 indicates that it contains an intramembrane cholesterol-binding pocket and that interaction with cholesterol may regulate a conformational switch in the extracellular domain of CD81. Therefore, CD81 possesses a potential cholesterol sensing mechanism; however, its relevance for protein function is thus far unknown. In this study we investigate CD81 cholesterol sensing in the context of its activity as a receptor for hepatitis C virus. Structure-led mutagenesis of the cholesterol-binding pocket reduced CD81-cholesterol association, but had disparate effects on HCV, both reducing and enhancing CD81 receptor activity. We reasoned that this could be explained by alterations in the consequences of cholesterol binding. To investigate this further we performed molecular dynamic simulations of CD81 with and without cholesterol; this identified an allosteric mechanism by which cholesterol binding regulates the conformation of CD81. To test this, we designed further mutations to force CD81 into either the open (cholesterol unbound) or closed (cholesterol bound) conformation. The open mutant of CD81 exhibited reduced receptor activity whereas the closed mutant was enhanced. These data are consistent with cholesterol switching CD81 between a receptor active and inactive state. CD81 interactome analysis also suggests that conformational switching may modulate the assembly of CD81-partner networks. This work furthers our understanding of the molecular mechanism of CD81 cholesterol sensing, how this relates to HCV entry and CD81’s function as a molecular scaffold; these insights are relevant to CD81’s varied roles in health and disease

Analysis of Bile Colonization and Intestinal Flora may Improve Management in Liver Transplant Recipients Undergoing ERCP

Background: Immunosuppression, denervation of biliary tract, and presence of biliary strictures favor colonization of bile with microorganisms after liver transplantation. Little is known about spectrum and antibiotic susceptibility of this colonization. Material and Methods: Bile and feces were collected prospectively from 38 patients who underwent endoscopic retrograde cholangiopancreaticography after liver transplantation. Samples were analyzed for colonization and antibiotic susceptibility. Results: From the 38 tested bile samples, 86.6% tested positive. Of those, 26 (78.8%) were polymicrobial. Of isolated bile samples, 52 (64.2%) were gram-positive, 22.2% were gram-negative, and 13.6% revealed Candida albicans. Most detectable gram-positive bacteria were Enterococcus faecium. Most detectable gram-negative bacteria were E. coli and Klebsiella pneumonia. Our analyses revealed high resistance rates of the isolates. Only 55.6% of isolates were sensitive to ciprofloxacin, 54% were sensitive to piperacillin/tazobactam, and 60.3% were sensitive to imipenem. High susceptibility rates were found for linezolid and vancomycin (72.9% and 72.6%, respectively). We found a high correlation between microorganisms found in bile and those isolated from stool. Conclusions: Bile of liver transplant recipients is frequently colonized with microorganisms. The starting point of this colonization is usually the intestine. Systematic analysis of bile colonization during endoscopic interventions on biliary tracts of liver transplant recipients might help to select effective prophylactic antibiotic regimes as well as to facilitate the choice of suitable antimicrobial therapy in case of septic complications